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Message-ID: <157867915986.30329.17500949467391840558.tip-bot2@tip-bot2>
Date: Fri, 10 Jan 2020 17:59:19 -0000
From: "tip-bot2 for Ingo Molnar" <tip-bot2@...utronix.de>
To: linux-tip-commits@...r.kernel.org
Cc: Ingo Molnar <mingo@...nel.org>, x86 <x86@...nel.org>,
LKML <linux-kernel@...r.kernel.org>
Subject: [tip: x86/mm] x86/mm/pat: Move the memtype related files to arch/x86/mm/pat/
The following commit has been merged into the x86/mm branch of tip:
Commit-ID: f9b57cf80c8b585614ba223732be0d8f19d558d8
Gitweb: https://git.kernel.org/tip/f9b57cf80c8b585614ba223732be0d8f19d558d8
Author: Ingo Molnar <mingo@...nel.org>
AuthorDate: Tue, 10 Dec 2019 10:08:09 +01:00
Committer: Ingo Molnar <mingo@...nel.org>
CommitterDate: Tue, 10 Dec 2019 10:12:55 +01:00
x86/mm/pat: Move the memtype related files to arch/x86/mm/pat/
- pat.c offers, dominantly, the memtype APIs - so rename it to memtype.c.
- pageattr.c is offering, primarily, the set_memory*() page attribute APIs,
which is offered via the <asm/set_memory.h> header: name the .c file
along the same pattern.
I.e. perform these renames, and move them all next to each other in arch/x86/mm/pat/:
pat.c => memtype.c
pat_internal.h => memtype.h
pat_interval.c => memtype_interval.c
pageattr.c => set_memory.c
pageattr-test.c => cpa-test.c
Signed-off-by: Ingo Molnar <mingo@...nel.org>
---
arch/x86/mm/Makefile | 8 +-
arch/x86/mm/pageattr-test.c | 278 +---
arch/x86/mm/pageattr.c | 2285 +---------------------------
arch/x86/mm/pat.c | 1219 +--------------
arch/x86/mm/pat/Makefile | 5 +-
arch/x86/mm/pat/cpa-test.c | 278 +++-
arch/x86/mm/pat/memtype.c | 1219 ++++++++++++++-
arch/x86/mm/pat/memtype.h | 49 +-
arch/x86/mm/pat/memtype_interval.c | 194 ++-
arch/x86/mm/pat/set_memory.c | 2285 +++++++++++++++++++++++++++-
arch/x86/mm/pat_internal.h | 49 +-
arch/x86/mm/pat_interval.c | 194 +--
12 files changed, 4034 insertions(+), 4029 deletions(-)
delete mode 100644 arch/x86/mm/pageattr-test.c
delete mode 100644 arch/x86/mm/pageattr.c
delete mode 100644 arch/x86/mm/pat.c
create mode 100644 arch/x86/mm/pat/Makefile
create mode 100644 arch/x86/mm/pat/cpa-test.c
create mode 100644 arch/x86/mm/pat/memtype.c
create mode 100644 arch/x86/mm/pat/memtype.h
create mode 100644 arch/x86/mm/pat/memtype_interval.c
create mode 100644 arch/x86/mm/pat/set_memory.c
delete mode 100644 arch/x86/mm/pat_internal.h
delete mode 100644 arch/x86/mm/pat_interval.c
diff --git a/arch/x86/mm/Makefile b/arch/x86/mm/Makefile
index 3b89c20..345848f 100644
--- a/arch/x86/mm/Makefile
+++ b/arch/x86/mm/Makefile
@@ -12,8 +12,10 @@ CFLAGS_REMOVE_mem_encrypt.o = -pg
CFLAGS_REMOVE_mem_encrypt_identity.o = -pg
endif
-obj-y := init.o init_$(BITS).o fault.o ioremap.o extable.o pageattr.o mmap.o \
- pat.o pgtable.o physaddr.o setup_nx.o tlb.o cpu_entry_area.o maccess.o
+obj-y := init.o init_$(BITS).o fault.o ioremap.o extable.o mmap.o \
+ pgtable.o physaddr.o setup_nx.o tlb.o cpu_entry_area.o maccess.o
+
+obj-y += pat/
# Make sure __phys_addr has no stackprotector
nostackp := $(call cc-option, -fno-stack-protector)
@@ -23,8 +25,6 @@ CFLAGS_mem_encrypt_identity.o := $(nostackp)
CFLAGS_fault.o := -I $(srctree)/$(src)/../include/asm/trace
-obj-$(CONFIG_X86_PAT) += pat_interval.o
-
obj-$(CONFIG_X86_32) += pgtable_32.o iomap_32.o
obj-$(CONFIG_HUGETLB_PAGE) += hugetlbpage.o
diff --git a/arch/x86/mm/pageattr-test.c b/arch/x86/mm/pageattr-test.c
deleted file mode 100644
index facce27..0000000
--- a/arch/x86/mm/pageattr-test.c
+++ /dev/null
@@ -1,278 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0
-/*
- * self test for change_page_attr.
- *
- * Clears the a test pte bit on random pages in the direct mapping,
- * then reverts and compares page tables forwards and afterwards.
- */
-#include <linux/memblock.h>
-#include <linux/kthread.h>
-#include <linux/random.h>
-#include <linux/kernel.h>
-#include <linux/init.h>
-#include <linux/mm.h>
-#include <linux/vmalloc.h>
-
-#include <asm/cacheflush.h>
-#include <asm/pgtable.h>
-#include <asm/kdebug.h>
-
-/*
- * Only print the results of the first pass:
- */
-static __read_mostly int print = 1;
-
-enum {
- NTEST = 3 * 100,
- NPAGES = 100,
-#ifdef CONFIG_X86_64
- LPS = (1 << PMD_SHIFT),
-#elif defined(CONFIG_X86_PAE)
- LPS = (1 << PMD_SHIFT),
-#else
- LPS = (1 << 22),
-#endif
- GPS = (1<<30)
-};
-
-#define PAGE_CPA_TEST __pgprot(_PAGE_CPA_TEST)
-
-static int pte_testbit(pte_t pte)
-{
- return pte_flags(pte) & _PAGE_SOFTW1;
-}
-
-struct split_state {
- long lpg, gpg, spg, exec;
- long min_exec, max_exec;
-};
-
-static int print_split(struct split_state *s)
-{
- long i, expected, missed = 0;
- int err = 0;
-
- s->lpg = s->gpg = s->spg = s->exec = 0;
- s->min_exec = ~0UL;
- s->max_exec = 0;
- for (i = 0; i < max_pfn_mapped; ) {
- unsigned long addr = (unsigned long)__va(i << PAGE_SHIFT);
- unsigned int level;
- pte_t *pte;
-
- pte = lookup_address(addr, &level);
- if (!pte) {
- missed++;
- i++;
- continue;
- }
-
- if (level == PG_LEVEL_1G && sizeof(long) == 8) {
- s->gpg++;
- i += GPS/PAGE_SIZE;
- } else if (level == PG_LEVEL_2M) {
- if ((pte_val(*pte) & _PAGE_PRESENT) && !(pte_val(*pte) & _PAGE_PSE)) {
- printk(KERN_ERR
- "%lx level %d but not PSE %Lx\n",
- addr, level, (u64)pte_val(*pte));
- err = 1;
- }
- s->lpg++;
- i += LPS/PAGE_SIZE;
- } else {
- s->spg++;
- i++;
- }
- if (!(pte_val(*pte) & _PAGE_NX)) {
- s->exec++;
- if (addr < s->min_exec)
- s->min_exec = addr;
- if (addr > s->max_exec)
- s->max_exec = addr;
- }
- }
- if (print) {
- printk(KERN_INFO
- " 4k %lu large %lu gb %lu x %lu[%lx-%lx] miss %lu\n",
- s->spg, s->lpg, s->gpg, s->exec,
- s->min_exec != ~0UL ? s->min_exec : 0,
- s->max_exec, missed);
- }
-
- expected = (s->gpg*GPS + s->lpg*LPS)/PAGE_SIZE + s->spg + missed;
- if (expected != i) {
- printk(KERN_ERR "CPA max_pfn_mapped %lu but expected %lu\n",
- max_pfn_mapped, expected);
- return 1;
- }
- return err;
-}
-
-static unsigned long addr[NTEST];
-static unsigned int len[NTEST];
-
-static struct page *pages[NPAGES];
-static unsigned long addrs[NPAGES];
-
-/* Change the global bit on random pages in the direct mapping */
-static int pageattr_test(void)
-{
- struct split_state sa, sb, sc;
- unsigned long *bm;
- pte_t *pte, pte0;
- int failed = 0;
- unsigned int level;
- int i, k;
- int err;
-
- if (print)
- printk(KERN_INFO "CPA self-test:\n");
-
- bm = vzalloc((max_pfn_mapped + 7) / 8);
- if (!bm) {
- printk(KERN_ERR "CPA Cannot vmalloc bitmap\n");
- return -ENOMEM;
- }
-
- failed += print_split(&sa);
-
- for (i = 0; i < NTEST; i++) {
- unsigned long pfn = prandom_u32() % max_pfn_mapped;
-
- addr[i] = (unsigned long)__va(pfn << PAGE_SHIFT);
- len[i] = prandom_u32() % NPAGES;
- len[i] = min_t(unsigned long, len[i], max_pfn_mapped - pfn - 1);
-
- if (len[i] == 0)
- len[i] = 1;
-
- pte = NULL;
- pte0 = pfn_pte(0, __pgprot(0)); /* shut gcc up */
-
- for (k = 0; k < len[i]; k++) {
- pte = lookup_address(addr[i] + k*PAGE_SIZE, &level);
- if (!pte || pgprot_val(pte_pgprot(*pte)) == 0 ||
- !(pte_val(*pte) & _PAGE_PRESENT)) {
- addr[i] = 0;
- break;
- }
- if (k == 0) {
- pte0 = *pte;
- } else {
- if (pgprot_val(pte_pgprot(*pte)) !=
- pgprot_val(pte_pgprot(pte0))) {
- len[i] = k;
- break;
- }
- }
- if (test_bit(pfn + k, bm)) {
- len[i] = k;
- break;
- }
- __set_bit(pfn + k, bm);
- addrs[k] = addr[i] + k*PAGE_SIZE;
- pages[k] = pfn_to_page(pfn + k);
- }
- if (!addr[i] || !pte || !k) {
- addr[i] = 0;
- continue;
- }
-
- switch (i % 3) {
- case 0:
- err = change_page_attr_set(&addr[i], len[i], PAGE_CPA_TEST, 0);
- break;
-
- case 1:
- err = change_page_attr_set(addrs, len[1], PAGE_CPA_TEST, 1);
- break;
-
- case 2:
- err = cpa_set_pages_array(pages, len[i], PAGE_CPA_TEST);
- break;
- }
-
-
- if (err < 0) {
- printk(KERN_ERR "CPA %d failed %d\n", i, err);
- failed++;
- }
-
- pte = lookup_address(addr[i], &level);
- if (!pte || !pte_testbit(*pte) || pte_huge(*pte)) {
- printk(KERN_ERR "CPA %lx: bad pte %Lx\n", addr[i],
- pte ? (u64)pte_val(*pte) : 0ULL);
- failed++;
- }
- if (level != PG_LEVEL_4K) {
- printk(KERN_ERR "CPA %lx: unexpected level %d\n",
- addr[i], level);
- failed++;
- }
-
- }
- vfree(bm);
-
- failed += print_split(&sb);
-
- for (i = 0; i < NTEST; i++) {
- if (!addr[i])
- continue;
- pte = lookup_address(addr[i], &level);
- if (!pte) {
- printk(KERN_ERR "CPA lookup of %lx failed\n", addr[i]);
- failed++;
- continue;
- }
- err = change_page_attr_clear(&addr[i], len[i], PAGE_CPA_TEST, 0);
- if (err < 0) {
- printk(KERN_ERR "CPA reverting failed: %d\n", err);
- failed++;
- }
- pte = lookup_address(addr[i], &level);
- if (!pte || pte_testbit(*pte)) {
- printk(KERN_ERR "CPA %lx: bad pte after revert %Lx\n",
- addr[i], pte ? (u64)pte_val(*pte) : 0ULL);
- failed++;
- }
-
- }
-
- failed += print_split(&sc);
-
- if (failed) {
- WARN(1, KERN_ERR "NOT PASSED. Please report.\n");
- return -EINVAL;
- } else {
- if (print)
- printk(KERN_INFO "ok.\n");
- }
-
- return 0;
-}
-
-static int do_pageattr_test(void *__unused)
-{
- while (!kthread_should_stop()) {
- schedule_timeout_interruptible(HZ*30);
- if (pageattr_test() < 0)
- break;
- if (print)
- print--;
- }
- return 0;
-}
-
-static int start_pageattr_test(void)
-{
- struct task_struct *p;
-
- p = kthread_create(do_pageattr_test, NULL, "pageattr-test");
- if (!IS_ERR(p))
- wake_up_process(p);
- else
- WARN_ON(1);
-
- return 0;
-}
-device_initcall(start_pageattr_test);
diff --git a/arch/x86/mm/pageattr.c b/arch/x86/mm/pageattr.c
deleted file mode 100644
index 1b99ad0..0000000
--- a/arch/x86/mm/pageattr.c
+++ /dev/null
@@ -1,2285 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0-only
-/*
- * Copyright 2002 Andi Kleen, SuSE Labs.
- * Thanks to Ben LaHaise for precious feedback.
- */
-#include <linux/highmem.h>
-#include <linux/memblock.h>
-#include <linux/sched.h>
-#include <linux/mm.h>
-#include <linux/interrupt.h>
-#include <linux/seq_file.h>
-#include <linux/debugfs.h>
-#include <linux/pfn.h>
-#include <linux/percpu.h>
-#include <linux/gfp.h>
-#include <linux/pci.h>
-#include <linux/vmalloc.h>
-
-#include <asm/e820/api.h>
-#include <asm/processor.h>
-#include <asm/tlbflush.h>
-#include <asm/sections.h>
-#include <asm/setup.h>
-#include <linux/uaccess.h>
-#include <asm/pgalloc.h>
-#include <asm/proto.h>
-#include <asm/pat.h>
-#include <asm/set_memory.h>
-
-#include "mm_internal.h"
-
-/*
- * The current flushing context - we pass it instead of 5 arguments:
- */
-struct cpa_data {
- unsigned long *vaddr;
- pgd_t *pgd;
- pgprot_t mask_set;
- pgprot_t mask_clr;
- unsigned long numpages;
- unsigned long curpage;
- unsigned long pfn;
- unsigned int flags;
- unsigned int force_split : 1,
- force_static_prot : 1;
- struct page **pages;
-};
-
-enum cpa_warn {
- CPA_CONFLICT,
- CPA_PROTECT,
- CPA_DETECT,
-};
-
-static const int cpa_warn_level = CPA_PROTECT;
-
-/*
- * Serialize cpa() (for !DEBUG_PAGEALLOC which uses large identity mappings)
- * using cpa_lock. So that we don't allow any other cpu, with stale large tlb
- * entries change the page attribute in parallel to some other cpu
- * splitting a large page entry along with changing the attribute.
- */
-static DEFINE_SPINLOCK(cpa_lock);
-
-#define CPA_FLUSHTLB 1
-#define CPA_ARRAY 2
-#define CPA_PAGES_ARRAY 4
-#define CPA_NO_CHECK_ALIAS 8 /* Do not search for aliases */
-
-#ifdef CONFIG_PROC_FS
-static unsigned long direct_pages_count[PG_LEVEL_NUM];
-
-void update_page_count(int level, unsigned long pages)
-{
- /* Protect against CPA */
- spin_lock(&pgd_lock);
- direct_pages_count[level] += pages;
- spin_unlock(&pgd_lock);
-}
-
-static void split_page_count(int level)
-{
- if (direct_pages_count[level] == 0)
- return;
-
- direct_pages_count[level]--;
- direct_pages_count[level - 1] += PTRS_PER_PTE;
-}
-
-void arch_report_meminfo(struct seq_file *m)
-{
- seq_printf(m, "DirectMap4k: %8lu kB\n",
- direct_pages_count[PG_LEVEL_4K] << 2);
-#if defined(CONFIG_X86_64) || defined(CONFIG_X86_PAE)
- seq_printf(m, "DirectMap2M: %8lu kB\n",
- direct_pages_count[PG_LEVEL_2M] << 11);
-#else
- seq_printf(m, "DirectMap4M: %8lu kB\n",
- direct_pages_count[PG_LEVEL_2M] << 12);
-#endif
- if (direct_gbpages)
- seq_printf(m, "DirectMap1G: %8lu kB\n",
- direct_pages_count[PG_LEVEL_1G] << 20);
-}
-#else
-static inline void split_page_count(int level) { }
-#endif
-
-#ifdef CONFIG_X86_CPA_STATISTICS
-
-static unsigned long cpa_1g_checked;
-static unsigned long cpa_1g_sameprot;
-static unsigned long cpa_1g_preserved;
-static unsigned long cpa_2m_checked;
-static unsigned long cpa_2m_sameprot;
-static unsigned long cpa_2m_preserved;
-static unsigned long cpa_4k_install;
-
-static inline void cpa_inc_1g_checked(void)
-{
- cpa_1g_checked++;
-}
-
-static inline void cpa_inc_2m_checked(void)
-{
- cpa_2m_checked++;
-}
-
-static inline void cpa_inc_4k_install(void)
-{
- cpa_4k_install++;
-}
-
-static inline void cpa_inc_lp_sameprot(int level)
-{
- if (level == PG_LEVEL_1G)
- cpa_1g_sameprot++;
- else
- cpa_2m_sameprot++;
-}
-
-static inline void cpa_inc_lp_preserved(int level)
-{
- if (level == PG_LEVEL_1G)
- cpa_1g_preserved++;
- else
- cpa_2m_preserved++;
-}
-
-static int cpastats_show(struct seq_file *m, void *p)
-{
- seq_printf(m, "1G pages checked: %16lu\n", cpa_1g_checked);
- seq_printf(m, "1G pages sameprot: %16lu\n", cpa_1g_sameprot);
- seq_printf(m, "1G pages preserved: %16lu\n", cpa_1g_preserved);
- seq_printf(m, "2M pages checked: %16lu\n", cpa_2m_checked);
- seq_printf(m, "2M pages sameprot: %16lu\n", cpa_2m_sameprot);
- seq_printf(m, "2M pages preserved: %16lu\n", cpa_2m_preserved);
- seq_printf(m, "4K pages set-checked: %16lu\n", cpa_4k_install);
- return 0;
-}
-
-static int cpastats_open(struct inode *inode, struct file *file)
-{
- return single_open(file, cpastats_show, NULL);
-}
-
-static const struct file_operations cpastats_fops = {
- .open = cpastats_open,
- .read = seq_read,
- .llseek = seq_lseek,
- .release = single_release,
-};
-
-static int __init cpa_stats_init(void)
-{
- debugfs_create_file("cpa_stats", S_IRUSR, arch_debugfs_dir, NULL,
- &cpastats_fops);
- return 0;
-}
-late_initcall(cpa_stats_init);
-#else
-static inline void cpa_inc_1g_checked(void) { }
-static inline void cpa_inc_2m_checked(void) { }
-static inline void cpa_inc_4k_install(void) { }
-static inline void cpa_inc_lp_sameprot(int level) { }
-static inline void cpa_inc_lp_preserved(int level) { }
-#endif
-
-
-static inline int
-within(unsigned long addr, unsigned long start, unsigned long end)
-{
- return addr >= start && addr < end;
-}
-
-static inline int
-within_inclusive(unsigned long addr, unsigned long start, unsigned long end)
-{
- return addr >= start && addr <= end;
-}
-
-#ifdef CONFIG_X86_64
-
-static inline unsigned long highmap_start_pfn(void)
-{
- return __pa_symbol(_text) >> PAGE_SHIFT;
-}
-
-static inline unsigned long highmap_end_pfn(void)
-{
- /* Do not reference physical address outside the kernel. */
- return __pa_symbol(roundup(_brk_end, PMD_SIZE) - 1) >> PAGE_SHIFT;
-}
-
-static bool __cpa_pfn_in_highmap(unsigned long pfn)
-{
- /*
- * Kernel text has an alias mapping at a high address, known
- * here as "highmap".
- */
- return within_inclusive(pfn, highmap_start_pfn(), highmap_end_pfn());
-}
-
-#else
-
-static bool __cpa_pfn_in_highmap(unsigned long pfn)
-{
- /* There is no highmap on 32-bit */
- return false;
-}
-
-#endif
-
-/*
- * See set_mce_nospec().
- *
- * Machine check recovery code needs to change cache mode of poisoned pages to
- * UC to avoid speculative access logging another error. But passing the
- * address of the 1:1 mapping to set_memory_uc() is a fine way to encourage a
- * speculative access. So we cheat and flip the top bit of the address. This
- * works fine for the code that updates the page tables. But at the end of the
- * process we need to flush the TLB and cache and the non-canonical address
- * causes a #GP fault when used by the INVLPG and CLFLUSH instructions.
- *
- * But in the common case we already have a canonical address. This code
- * will fix the top bit if needed and is a no-op otherwise.
- */
-static inline unsigned long fix_addr(unsigned long addr)
-{
-#ifdef CONFIG_X86_64
- return (long)(addr << 1) >> 1;
-#else
- return addr;
-#endif
-}
-
-static unsigned long __cpa_addr(struct cpa_data *cpa, unsigned long idx)
-{
- if (cpa->flags & CPA_PAGES_ARRAY) {
- struct page *page = cpa->pages[idx];
-
- if (unlikely(PageHighMem(page)))
- return 0;
-
- return (unsigned long)page_address(page);
- }
-
- if (cpa->flags & CPA_ARRAY)
- return cpa->vaddr[idx];
-
- return *cpa->vaddr + idx * PAGE_SIZE;
-}
-
-/*
- * Flushing functions
- */
-
-static void clflush_cache_range_opt(void *vaddr, unsigned int size)
-{
- const unsigned long clflush_size = boot_cpu_data.x86_clflush_size;
- void *p = (void *)((unsigned long)vaddr & ~(clflush_size - 1));
- void *vend = vaddr + size;
-
- if (p >= vend)
- return;
-
- for (; p < vend; p += clflush_size)
- clflushopt(p);
-}
-
-/**
- * clflush_cache_range - flush a cache range with clflush
- * @vaddr: virtual start address
- * @size: number of bytes to flush
- *
- * CLFLUSHOPT is an unordered instruction which needs fencing with MFENCE or
- * SFENCE to avoid ordering issues.
- */
-void clflush_cache_range(void *vaddr, unsigned int size)
-{
- mb();
- clflush_cache_range_opt(vaddr, size);
- mb();
-}
-EXPORT_SYMBOL_GPL(clflush_cache_range);
-
-void arch_invalidate_pmem(void *addr, size_t size)
-{
- clflush_cache_range(addr, size);
-}
-EXPORT_SYMBOL_GPL(arch_invalidate_pmem);
-
-static void __cpa_flush_all(void *arg)
-{
- unsigned long cache = (unsigned long)arg;
-
- /*
- * Flush all to work around Errata in early athlons regarding
- * large page flushing.
- */
- __flush_tlb_all();
-
- if (cache && boot_cpu_data.x86 >= 4)
- wbinvd();
-}
-
-static void cpa_flush_all(unsigned long cache)
-{
- BUG_ON(irqs_disabled() && !early_boot_irqs_disabled);
-
- on_each_cpu(__cpa_flush_all, (void *) cache, 1);
-}
-
-void __cpa_flush_tlb(void *data)
-{
- struct cpa_data *cpa = data;
- unsigned int i;
-
- for (i = 0; i < cpa->numpages; i++)
- __flush_tlb_one_kernel(fix_addr(__cpa_addr(cpa, i)));
-}
-
-static void cpa_flush(struct cpa_data *data, int cache)
-{
- struct cpa_data *cpa = data;
- unsigned int i;
-
- BUG_ON(irqs_disabled() && !early_boot_irqs_disabled);
-
- if (cache && !static_cpu_has(X86_FEATURE_CLFLUSH)) {
- cpa_flush_all(cache);
- return;
- }
-
- if (cpa->numpages <= tlb_single_page_flush_ceiling)
- on_each_cpu(__cpa_flush_tlb, cpa, 1);
- else
- flush_tlb_all();
-
- if (!cache)
- return;
-
- mb();
- for (i = 0; i < cpa->numpages; i++) {
- unsigned long addr = __cpa_addr(cpa, i);
- unsigned int level;
-
- pte_t *pte = lookup_address(addr, &level);
-
- /*
- * Only flush present addresses:
- */
- if (pte && (pte_val(*pte) & _PAGE_PRESENT))
- clflush_cache_range_opt((void *)fix_addr(addr), PAGE_SIZE);
- }
- mb();
-}
-
-static bool overlaps(unsigned long r1_start, unsigned long r1_end,
- unsigned long r2_start, unsigned long r2_end)
-{
- return (r1_start <= r2_end && r1_end >= r2_start) ||
- (r2_start <= r1_end && r2_end >= r1_start);
-}
-
-#ifdef CONFIG_PCI_BIOS
-/*
- * The BIOS area between 640k and 1Mb needs to be executable for PCI BIOS
- * based config access (CONFIG_PCI_GOBIOS) support.
- */
-#define BIOS_PFN PFN_DOWN(BIOS_BEGIN)
-#define BIOS_PFN_END PFN_DOWN(BIOS_END - 1)
-
-static pgprotval_t protect_pci_bios(unsigned long spfn, unsigned long epfn)
-{
- if (pcibios_enabled && overlaps(spfn, epfn, BIOS_PFN, BIOS_PFN_END))
- return _PAGE_NX;
- return 0;
-}
-#else
-static pgprotval_t protect_pci_bios(unsigned long spfn, unsigned long epfn)
-{
- return 0;
-}
-#endif
-
-/*
- * The .rodata section needs to be read-only. Using the pfn catches all
- * aliases. This also includes __ro_after_init, so do not enforce until
- * kernel_set_to_readonly is true.
- */
-static pgprotval_t protect_rodata(unsigned long spfn, unsigned long epfn)
-{
- unsigned long epfn_ro, spfn_ro = PFN_DOWN(__pa_symbol(__start_rodata));
-
- /*
- * Note: __end_rodata is at page aligned and not inclusive, so
- * subtract 1 to get the last enforced PFN in the rodata area.
- */
- epfn_ro = PFN_DOWN(__pa_symbol(__end_rodata)) - 1;
-
- if (kernel_set_to_readonly && overlaps(spfn, epfn, spfn_ro, epfn_ro))
- return _PAGE_RW;
- return 0;
-}
-
-/*
- * Protect kernel text against becoming non executable by forbidding
- * _PAGE_NX. This protects only the high kernel mapping (_text -> _etext)
- * out of which the kernel actually executes. Do not protect the low
- * mapping.
- *
- * This does not cover __inittext since that is gone after boot.
- */
-static pgprotval_t protect_kernel_text(unsigned long start, unsigned long end)
-{
- unsigned long t_end = (unsigned long)_etext - 1;
- unsigned long t_start = (unsigned long)_text;
-
- if (overlaps(start, end, t_start, t_end))
- return _PAGE_NX;
- return 0;
-}
-
-#if defined(CONFIG_X86_64)
-/*
- * Once the kernel maps the text as RO (kernel_set_to_readonly is set),
- * kernel text mappings for the large page aligned text, rodata sections
- * will be always read-only. For the kernel identity mappings covering the
- * holes caused by this alignment can be anything that user asks.
- *
- * This will preserve the large page mappings for kernel text/data at no
- * extra cost.
- */
-static pgprotval_t protect_kernel_text_ro(unsigned long start,
- unsigned long end)
-{
- unsigned long t_end = (unsigned long)__end_rodata_hpage_align - 1;
- unsigned long t_start = (unsigned long)_text;
- unsigned int level;
-
- if (!kernel_set_to_readonly || !overlaps(start, end, t_start, t_end))
- return 0;
- /*
- * Don't enforce the !RW mapping for the kernel text mapping, if
- * the current mapping is already using small page mapping. No
- * need to work hard to preserve large page mappings in this case.
- *
- * This also fixes the Linux Xen paravirt guest boot failure caused
- * by unexpected read-only mappings for kernel identity
- * mappings. In this paravirt guest case, the kernel text mapping
- * and the kernel identity mapping share the same page-table pages,
- * so the protections for kernel text and identity mappings have to
- * be the same.
- */
- if (lookup_address(start, &level) && (level != PG_LEVEL_4K))
- return _PAGE_RW;
- return 0;
-}
-#else
-static pgprotval_t protect_kernel_text_ro(unsigned long start,
- unsigned long end)
-{
- return 0;
-}
-#endif
-
-static inline bool conflicts(pgprot_t prot, pgprotval_t val)
-{
- return (pgprot_val(prot) & ~val) != pgprot_val(prot);
-}
-
-static inline void check_conflict(int warnlvl, pgprot_t prot, pgprotval_t val,
- unsigned long start, unsigned long end,
- unsigned long pfn, const char *txt)
-{
- static const char *lvltxt[] = {
- [CPA_CONFLICT] = "conflict",
- [CPA_PROTECT] = "protect",
- [CPA_DETECT] = "detect",
- };
-
- if (warnlvl > cpa_warn_level || !conflicts(prot, val))
- return;
-
- pr_warn("CPA %8s %10s: 0x%016lx - 0x%016lx PFN %lx req %016llx prevent %016llx\n",
- lvltxt[warnlvl], txt, start, end, pfn, (unsigned long long)pgprot_val(prot),
- (unsigned long long)val);
-}
-
-/*
- * Certain areas of memory on x86 require very specific protection flags,
- * for example the BIOS area or kernel text. Callers don't always get this
- * right (again, ioremap() on BIOS memory is not uncommon) so this function
- * checks and fixes these known static required protection bits.
- */
-static inline pgprot_t static_protections(pgprot_t prot, unsigned long start,
- unsigned long pfn, unsigned long npg,
- unsigned long lpsize, int warnlvl)
-{
- pgprotval_t forbidden, res;
- unsigned long end;
-
- /*
- * There is no point in checking RW/NX conflicts when the requested
- * mapping is setting the page !PRESENT.
- */
- if (!(pgprot_val(prot) & _PAGE_PRESENT))
- return prot;
-
- /* Operate on the virtual address */
- end = start + npg * PAGE_SIZE - 1;
-
- res = protect_kernel_text(start, end);
- check_conflict(warnlvl, prot, res, start, end, pfn, "Text NX");
- forbidden = res;
-
- /*
- * Special case to preserve a large page. If the change spawns the
- * full large page mapping then there is no point to split it
- * up. Happens with ftrace and is going to be removed once ftrace
- * switched to text_poke().
- */
- if (lpsize != (npg * PAGE_SIZE) || (start & (lpsize - 1))) {
- res = protect_kernel_text_ro(start, end);
- check_conflict(warnlvl, prot, res, start, end, pfn, "Text RO");
- forbidden |= res;
- }
-
- /* Check the PFN directly */
- res = protect_pci_bios(pfn, pfn + npg - 1);
- check_conflict(warnlvl, prot, res, start, end, pfn, "PCIBIOS NX");
- forbidden |= res;
-
- res = protect_rodata(pfn, pfn + npg - 1);
- check_conflict(warnlvl, prot, res, start, end, pfn, "Rodata RO");
- forbidden |= res;
-
- return __pgprot(pgprot_val(prot) & ~forbidden);
-}
-
-/*
- * Lookup the page table entry for a virtual address in a specific pgd.
- * Return a pointer to the entry and the level of the mapping.
- */
-pte_t *lookup_address_in_pgd(pgd_t *pgd, unsigned long address,
- unsigned int *level)
-{
- p4d_t *p4d;
- pud_t *pud;
- pmd_t *pmd;
-
- *level = PG_LEVEL_NONE;
-
- if (pgd_none(*pgd))
- return NULL;
-
- p4d = p4d_offset(pgd, address);
- if (p4d_none(*p4d))
- return NULL;
-
- *level = PG_LEVEL_512G;
- if (p4d_large(*p4d) || !p4d_present(*p4d))
- return (pte_t *)p4d;
-
- pud = pud_offset(p4d, address);
- if (pud_none(*pud))
- return NULL;
-
- *level = PG_LEVEL_1G;
- if (pud_large(*pud) || !pud_present(*pud))
- return (pte_t *)pud;
-
- pmd = pmd_offset(pud, address);
- if (pmd_none(*pmd))
- return NULL;
-
- *level = PG_LEVEL_2M;
- if (pmd_large(*pmd) || !pmd_present(*pmd))
- return (pte_t *)pmd;
-
- *level = PG_LEVEL_4K;
-
- return pte_offset_kernel(pmd, address);
-}
-
-/*
- * Lookup the page table entry for a virtual address. Return a pointer
- * to the entry and the level of the mapping.
- *
- * Note: We return pud and pmd either when the entry is marked large
- * or when the present bit is not set. Otherwise we would return a
- * pointer to a nonexisting mapping.
- */
-pte_t *lookup_address(unsigned long address, unsigned int *level)
-{
- return lookup_address_in_pgd(pgd_offset_k(address), address, level);
-}
-EXPORT_SYMBOL_GPL(lookup_address);
-
-static pte_t *_lookup_address_cpa(struct cpa_data *cpa, unsigned long address,
- unsigned int *level)
-{
- if (cpa->pgd)
- return lookup_address_in_pgd(cpa->pgd + pgd_index(address),
- address, level);
-
- return lookup_address(address, level);
-}
-
-/*
- * Lookup the PMD entry for a virtual address. Return a pointer to the entry
- * or NULL if not present.
- */
-pmd_t *lookup_pmd_address(unsigned long address)
-{
- pgd_t *pgd;
- p4d_t *p4d;
- pud_t *pud;
-
- pgd = pgd_offset_k(address);
- if (pgd_none(*pgd))
- return NULL;
-
- p4d = p4d_offset(pgd, address);
- if (p4d_none(*p4d) || p4d_large(*p4d) || !p4d_present(*p4d))
- return NULL;
-
- pud = pud_offset(p4d, address);
- if (pud_none(*pud) || pud_large(*pud) || !pud_present(*pud))
- return NULL;
-
- return pmd_offset(pud, address);
-}
-
-/*
- * This is necessary because __pa() does not work on some
- * kinds of memory, like vmalloc() or the alloc_remap()
- * areas on 32-bit NUMA systems. The percpu areas can
- * end up in this kind of memory, for instance.
- *
- * This could be optimized, but it is only intended to be
- * used at inititalization time, and keeping it
- * unoptimized should increase the testing coverage for
- * the more obscure platforms.
- */
-phys_addr_t slow_virt_to_phys(void *__virt_addr)
-{
- unsigned long virt_addr = (unsigned long)__virt_addr;
- phys_addr_t phys_addr;
- unsigned long offset;
- enum pg_level level;
- pte_t *pte;
-
- pte = lookup_address(virt_addr, &level);
- BUG_ON(!pte);
-
- /*
- * pXX_pfn() returns unsigned long, which must be cast to phys_addr_t
- * before being left-shifted PAGE_SHIFT bits -- this trick is to
- * make 32-PAE kernel work correctly.
- */
- switch (level) {
- case PG_LEVEL_1G:
- phys_addr = (phys_addr_t)pud_pfn(*(pud_t *)pte) << PAGE_SHIFT;
- offset = virt_addr & ~PUD_PAGE_MASK;
- break;
- case PG_LEVEL_2M:
- phys_addr = (phys_addr_t)pmd_pfn(*(pmd_t *)pte) << PAGE_SHIFT;
- offset = virt_addr & ~PMD_PAGE_MASK;
- break;
- default:
- phys_addr = (phys_addr_t)pte_pfn(*pte) << PAGE_SHIFT;
- offset = virt_addr & ~PAGE_MASK;
- }
-
- return (phys_addr_t)(phys_addr | offset);
-}
-EXPORT_SYMBOL_GPL(slow_virt_to_phys);
-
-/*
- * Set the new pmd in all the pgds we know about:
- */
-static void __set_pmd_pte(pte_t *kpte, unsigned long address, pte_t pte)
-{
- /* change init_mm */
- set_pte_atomic(kpte, pte);
-#ifdef CONFIG_X86_32
- if (!SHARED_KERNEL_PMD) {
- struct page *page;
-
- list_for_each_entry(page, &pgd_list, lru) {
- pgd_t *pgd;
- p4d_t *p4d;
- pud_t *pud;
- pmd_t *pmd;
-
- pgd = (pgd_t *)page_address(page) + pgd_index(address);
- p4d = p4d_offset(pgd, address);
- pud = pud_offset(p4d, address);
- pmd = pmd_offset(pud, address);
- set_pte_atomic((pte_t *)pmd, pte);
- }
- }
-#endif
-}
-
-static pgprot_t pgprot_clear_protnone_bits(pgprot_t prot)
-{
- /*
- * _PAGE_GLOBAL means "global page" for present PTEs.
- * But, it is also used to indicate _PAGE_PROTNONE
- * for non-present PTEs.
- *
- * This ensures that a _PAGE_GLOBAL PTE going from
- * present to non-present is not confused as
- * _PAGE_PROTNONE.
- */
- if (!(pgprot_val(prot) & _PAGE_PRESENT))
- pgprot_val(prot) &= ~_PAGE_GLOBAL;
-
- return prot;
-}
-
-static int __should_split_large_page(pte_t *kpte, unsigned long address,
- struct cpa_data *cpa)
-{
- unsigned long numpages, pmask, psize, lpaddr, pfn, old_pfn;
- pgprot_t old_prot, new_prot, req_prot, chk_prot;
- pte_t new_pte, *tmp;
- enum pg_level level;
-
- /*
- * Check for races, another CPU might have split this page
- * up already:
- */
- tmp = _lookup_address_cpa(cpa, address, &level);
- if (tmp != kpte)
- return 1;
-
- switch (level) {
- case PG_LEVEL_2M:
- old_prot = pmd_pgprot(*(pmd_t *)kpte);
- old_pfn = pmd_pfn(*(pmd_t *)kpte);
- cpa_inc_2m_checked();
- break;
- case PG_LEVEL_1G:
- old_prot = pud_pgprot(*(pud_t *)kpte);
- old_pfn = pud_pfn(*(pud_t *)kpte);
- cpa_inc_1g_checked();
- break;
- default:
- return -EINVAL;
- }
-
- psize = page_level_size(level);
- pmask = page_level_mask(level);
-
- /*
- * Calculate the number of pages, which fit into this large
- * page starting at address:
- */
- lpaddr = (address + psize) & pmask;
- numpages = (lpaddr - address) >> PAGE_SHIFT;
- if (numpages < cpa->numpages)
- cpa->numpages = numpages;
-
- /*
- * We are safe now. Check whether the new pgprot is the same:
- * Convert protection attributes to 4k-format, as cpa->mask* are set
- * up accordingly.
- */
-
- /* Clear PSE (aka _PAGE_PAT) and move PAT bit to correct position */
- req_prot = pgprot_large_2_4k(old_prot);
-
- pgprot_val(req_prot) &= ~pgprot_val(cpa->mask_clr);
- pgprot_val(req_prot) |= pgprot_val(cpa->mask_set);
-
- /*
- * req_prot is in format of 4k pages. It must be converted to large
- * page format: the caching mode includes the PAT bit located at
- * different bit positions in the two formats.
- */
- req_prot = pgprot_4k_2_large(req_prot);
- req_prot = pgprot_clear_protnone_bits(req_prot);
- if (pgprot_val(req_prot) & _PAGE_PRESENT)
- pgprot_val(req_prot) |= _PAGE_PSE;
-
- /*
- * old_pfn points to the large page base pfn. So we need to add the
- * offset of the virtual address:
- */
- pfn = old_pfn + ((address & (psize - 1)) >> PAGE_SHIFT);
- cpa->pfn = pfn;
-
- /*
- * Calculate the large page base address and the number of 4K pages
- * in the large page
- */
- lpaddr = address & pmask;
- numpages = psize >> PAGE_SHIFT;
-
- /*
- * Sanity check that the existing mapping is correct versus the static
- * protections. static_protections() guards against !PRESENT, so no
- * extra conditional required here.
- */
- chk_prot = static_protections(old_prot, lpaddr, old_pfn, numpages,
- psize, CPA_CONFLICT);
-
- if (WARN_ON_ONCE(pgprot_val(chk_prot) != pgprot_val(old_prot))) {
- /*
- * Split the large page and tell the split code to
- * enforce static protections.
- */
- cpa->force_static_prot = 1;
- return 1;
- }
-
- /*
- * Optimization: If the requested pgprot is the same as the current
- * pgprot, then the large page can be preserved and no updates are
- * required independent of alignment and length of the requested
- * range. The above already established that the current pgprot is
- * correct, which in consequence makes the requested pgprot correct
- * as well if it is the same. The static protection scan below will
- * not come to a different conclusion.
- */
- if (pgprot_val(req_prot) == pgprot_val(old_prot)) {
- cpa_inc_lp_sameprot(level);
- return 0;
- }
-
- /*
- * If the requested range does not cover the full page, split it up
- */
- if (address != lpaddr || cpa->numpages != numpages)
- return 1;
-
- /*
- * Check whether the requested pgprot is conflicting with a static
- * protection requirement in the large page.
- */
- new_prot = static_protections(req_prot, lpaddr, old_pfn, numpages,
- psize, CPA_DETECT);
-
- /*
- * If there is a conflict, split the large page.
- *
- * There used to be a 4k wise evaluation trying really hard to
- * preserve the large pages, but experimentation has shown, that this
- * does not help at all. There might be corner cases which would
- * preserve one large page occasionally, but it's really not worth the
- * extra code and cycles for the common case.
- */
- if (pgprot_val(req_prot) != pgprot_val(new_prot))
- return 1;
-
- /* All checks passed. Update the large page mapping. */
- new_pte = pfn_pte(old_pfn, new_prot);
- __set_pmd_pte(kpte, address, new_pte);
- cpa->flags |= CPA_FLUSHTLB;
- cpa_inc_lp_preserved(level);
- return 0;
-}
-
-static int should_split_large_page(pte_t *kpte, unsigned long address,
- struct cpa_data *cpa)
-{
- int do_split;
-
- if (cpa->force_split)
- return 1;
-
- spin_lock(&pgd_lock);
- do_split = __should_split_large_page(kpte, address, cpa);
- spin_unlock(&pgd_lock);
-
- return do_split;
-}
-
-static void split_set_pte(struct cpa_data *cpa, pte_t *pte, unsigned long pfn,
- pgprot_t ref_prot, unsigned long address,
- unsigned long size)
-{
- unsigned int npg = PFN_DOWN(size);
- pgprot_t prot;
-
- /*
- * If should_split_large_page() discovered an inconsistent mapping,
- * remove the invalid protection in the split mapping.
- */
- if (!cpa->force_static_prot)
- goto set;
-
- /* Hand in lpsize = 0 to enforce the protection mechanism */
- prot = static_protections(ref_prot, address, pfn, npg, 0, CPA_PROTECT);
-
- if (pgprot_val(prot) == pgprot_val(ref_prot))
- goto set;
-
- /*
- * If this is splitting a PMD, fix it up. PUD splits cannot be
- * fixed trivially as that would require to rescan the newly
- * installed PMD mappings after returning from split_large_page()
- * so an eventual further split can allocate the necessary PTE
- * pages. Warn for now and revisit it in case this actually
- * happens.
- */
- if (size == PAGE_SIZE)
- ref_prot = prot;
- else
- pr_warn_once("CPA: Cannot fixup static protections for PUD split\n");
-set:
- set_pte(pte, pfn_pte(pfn, ref_prot));
-}
-
-static int
-__split_large_page(struct cpa_data *cpa, pte_t *kpte, unsigned long address,
- struct page *base)
-{
- unsigned long lpaddr, lpinc, ref_pfn, pfn, pfninc = 1;
- pte_t *pbase = (pte_t *)page_address(base);
- unsigned int i, level;
- pgprot_t ref_prot;
- pte_t *tmp;
-
- spin_lock(&pgd_lock);
- /*
- * Check for races, another CPU might have split this page
- * up for us already:
- */
- tmp = _lookup_address_cpa(cpa, address, &level);
- if (tmp != kpte) {
- spin_unlock(&pgd_lock);
- return 1;
- }
-
- paravirt_alloc_pte(&init_mm, page_to_pfn(base));
-
- switch (level) {
- case PG_LEVEL_2M:
- ref_prot = pmd_pgprot(*(pmd_t *)kpte);
- /*
- * Clear PSE (aka _PAGE_PAT) and move
- * PAT bit to correct position.
- */
- ref_prot = pgprot_large_2_4k(ref_prot);
- ref_pfn = pmd_pfn(*(pmd_t *)kpte);
- lpaddr = address & PMD_MASK;
- lpinc = PAGE_SIZE;
- break;
-
- case PG_LEVEL_1G:
- ref_prot = pud_pgprot(*(pud_t *)kpte);
- ref_pfn = pud_pfn(*(pud_t *)kpte);
- pfninc = PMD_PAGE_SIZE >> PAGE_SHIFT;
- lpaddr = address & PUD_MASK;
- lpinc = PMD_SIZE;
- /*
- * Clear the PSE flags if the PRESENT flag is not set
- * otherwise pmd_present/pmd_huge will return true
- * even on a non present pmd.
- */
- if (!(pgprot_val(ref_prot) & _PAGE_PRESENT))
- pgprot_val(ref_prot) &= ~_PAGE_PSE;
- break;
-
- default:
- spin_unlock(&pgd_lock);
- return 1;
- }
-
- ref_prot = pgprot_clear_protnone_bits(ref_prot);
-
- /*
- * Get the target pfn from the original entry:
- */
- pfn = ref_pfn;
- for (i = 0; i < PTRS_PER_PTE; i++, pfn += pfninc, lpaddr += lpinc)
- split_set_pte(cpa, pbase + i, pfn, ref_prot, lpaddr, lpinc);
-
- if (virt_addr_valid(address)) {
- unsigned long pfn = PFN_DOWN(__pa(address));
-
- if (pfn_range_is_mapped(pfn, pfn + 1))
- split_page_count(level);
- }
-
- /*
- * Install the new, split up pagetable.
- *
- * We use the standard kernel pagetable protections for the new
- * pagetable protections, the actual ptes set above control the
- * primary protection behavior:
- */
- __set_pmd_pte(kpte, address, mk_pte(base, __pgprot(_KERNPG_TABLE)));
-
- /*
- * Do a global flush tlb after splitting the large page
- * and before we do the actual change page attribute in the PTE.
- *
- * Without this, we violate the TLB application note, that says:
- * "The TLBs may contain both ordinary and large-page
- * translations for a 4-KByte range of linear addresses. This
- * may occur if software modifies the paging structures so that
- * the page size used for the address range changes. If the two
- * translations differ with respect to page frame or attributes
- * (e.g., permissions), processor behavior is undefined and may
- * be implementation-specific."
- *
- * We do this global tlb flush inside the cpa_lock, so that we
- * don't allow any other cpu, with stale tlb entries change the
- * page attribute in parallel, that also falls into the
- * just split large page entry.
- */
- flush_tlb_all();
- spin_unlock(&pgd_lock);
-
- return 0;
-}
-
-static int split_large_page(struct cpa_data *cpa, pte_t *kpte,
- unsigned long address)
-{
- struct page *base;
-
- if (!debug_pagealloc_enabled())
- spin_unlock(&cpa_lock);
- base = alloc_pages(GFP_KERNEL, 0);
- if (!debug_pagealloc_enabled())
- spin_lock(&cpa_lock);
- if (!base)
- return -ENOMEM;
-
- if (__split_large_page(cpa, kpte, address, base))
- __free_page(base);
-
- return 0;
-}
-
-static bool try_to_free_pte_page(pte_t *pte)
-{
- int i;
-
- for (i = 0; i < PTRS_PER_PTE; i++)
- if (!pte_none(pte[i]))
- return false;
-
- free_page((unsigned long)pte);
- return true;
-}
-
-static bool try_to_free_pmd_page(pmd_t *pmd)
-{
- int i;
-
- for (i = 0; i < PTRS_PER_PMD; i++)
- if (!pmd_none(pmd[i]))
- return false;
-
- free_page((unsigned long)pmd);
- return true;
-}
-
-static bool unmap_pte_range(pmd_t *pmd, unsigned long start, unsigned long end)
-{
- pte_t *pte = pte_offset_kernel(pmd, start);
-
- while (start < end) {
- set_pte(pte, __pte(0));
-
- start += PAGE_SIZE;
- pte++;
- }
-
- if (try_to_free_pte_page((pte_t *)pmd_page_vaddr(*pmd))) {
- pmd_clear(pmd);
- return true;
- }
- return false;
-}
-
-static void __unmap_pmd_range(pud_t *pud, pmd_t *pmd,
- unsigned long start, unsigned long end)
-{
- if (unmap_pte_range(pmd, start, end))
- if (try_to_free_pmd_page((pmd_t *)pud_page_vaddr(*pud)))
- pud_clear(pud);
-}
-
-static void unmap_pmd_range(pud_t *pud, unsigned long start, unsigned long end)
-{
- pmd_t *pmd = pmd_offset(pud, start);
-
- /*
- * Not on a 2MB page boundary?
- */
- if (start & (PMD_SIZE - 1)) {
- unsigned long next_page = (start + PMD_SIZE) & PMD_MASK;
- unsigned long pre_end = min_t(unsigned long, end, next_page);
-
- __unmap_pmd_range(pud, pmd, start, pre_end);
-
- start = pre_end;
- pmd++;
- }
-
- /*
- * Try to unmap in 2M chunks.
- */
- while (end - start >= PMD_SIZE) {
- if (pmd_large(*pmd))
- pmd_clear(pmd);
- else
- __unmap_pmd_range(pud, pmd, start, start + PMD_SIZE);
-
- start += PMD_SIZE;
- pmd++;
- }
-
- /*
- * 4K leftovers?
- */
- if (start < end)
- return __unmap_pmd_range(pud, pmd, start, end);
-
- /*
- * Try again to free the PMD page if haven't succeeded above.
- */
- if (!pud_none(*pud))
- if (try_to_free_pmd_page((pmd_t *)pud_page_vaddr(*pud)))
- pud_clear(pud);
-}
-
-static void unmap_pud_range(p4d_t *p4d, unsigned long start, unsigned long end)
-{
- pud_t *pud = pud_offset(p4d, start);
-
- /*
- * Not on a GB page boundary?
- */
- if (start & (PUD_SIZE - 1)) {
- unsigned long next_page = (start + PUD_SIZE) & PUD_MASK;
- unsigned long pre_end = min_t(unsigned long, end, next_page);
-
- unmap_pmd_range(pud, start, pre_end);
-
- start = pre_end;
- pud++;
- }
-
- /*
- * Try to unmap in 1G chunks?
- */
- while (end - start >= PUD_SIZE) {
-
- if (pud_large(*pud))
- pud_clear(pud);
- else
- unmap_pmd_range(pud, start, start + PUD_SIZE);
-
- start += PUD_SIZE;
- pud++;
- }
-
- /*
- * 2M leftovers?
- */
- if (start < end)
- unmap_pmd_range(pud, start, end);
-
- /*
- * No need to try to free the PUD page because we'll free it in
- * populate_pgd's error path
- */
-}
-
-static int alloc_pte_page(pmd_t *pmd)
-{
- pte_t *pte = (pte_t *)get_zeroed_page(GFP_KERNEL);
- if (!pte)
- return -1;
-
- set_pmd(pmd, __pmd(__pa(pte) | _KERNPG_TABLE));
- return 0;
-}
-
-static int alloc_pmd_page(pud_t *pud)
-{
- pmd_t *pmd = (pmd_t *)get_zeroed_page(GFP_KERNEL);
- if (!pmd)
- return -1;
-
- set_pud(pud, __pud(__pa(pmd) | _KERNPG_TABLE));
- return 0;
-}
-
-static void populate_pte(struct cpa_data *cpa,
- unsigned long start, unsigned long end,
- unsigned num_pages, pmd_t *pmd, pgprot_t pgprot)
-{
- pte_t *pte;
-
- pte = pte_offset_kernel(pmd, start);
-
- pgprot = pgprot_clear_protnone_bits(pgprot);
-
- while (num_pages-- && start < end) {
- set_pte(pte, pfn_pte(cpa->pfn, pgprot));
-
- start += PAGE_SIZE;
- cpa->pfn++;
- pte++;
- }
-}
-
-static long populate_pmd(struct cpa_data *cpa,
- unsigned long start, unsigned long end,
- unsigned num_pages, pud_t *pud, pgprot_t pgprot)
-{
- long cur_pages = 0;
- pmd_t *pmd;
- pgprot_t pmd_pgprot;
-
- /*
- * Not on a 2M boundary?
- */
- if (start & (PMD_SIZE - 1)) {
- unsigned long pre_end = start + (num_pages << PAGE_SHIFT);
- unsigned long next_page = (start + PMD_SIZE) & PMD_MASK;
-
- pre_end = min_t(unsigned long, pre_end, next_page);
- cur_pages = (pre_end - start) >> PAGE_SHIFT;
- cur_pages = min_t(unsigned int, num_pages, cur_pages);
-
- /*
- * Need a PTE page?
- */
- pmd = pmd_offset(pud, start);
- if (pmd_none(*pmd))
- if (alloc_pte_page(pmd))
- return -1;
-
- populate_pte(cpa, start, pre_end, cur_pages, pmd, pgprot);
-
- start = pre_end;
- }
-
- /*
- * We mapped them all?
- */
- if (num_pages == cur_pages)
- return cur_pages;
-
- pmd_pgprot = pgprot_4k_2_large(pgprot);
-
- while (end - start >= PMD_SIZE) {
-
- /*
- * We cannot use a 1G page so allocate a PMD page if needed.
- */
- if (pud_none(*pud))
- if (alloc_pmd_page(pud))
- return -1;
-
- pmd = pmd_offset(pud, start);
-
- set_pmd(pmd, pmd_mkhuge(pfn_pmd(cpa->pfn,
- canon_pgprot(pmd_pgprot))));
-
- start += PMD_SIZE;
- cpa->pfn += PMD_SIZE >> PAGE_SHIFT;
- cur_pages += PMD_SIZE >> PAGE_SHIFT;
- }
-
- /*
- * Map trailing 4K pages.
- */
- if (start < end) {
- pmd = pmd_offset(pud, start);
- if (pmd_none(*pmd))
- if (alloc_pte_page(pmd))
- return -1;
-
- populate_pte(cpa, start, end, num_pages - cur_pages,
- pmd, pgprot);
- }
- return num_pages;
-}
-
-static int populate_pud(struct cpa_data *cpa, unsigned long start, p4d_t *p4d,
- pgprot_t pgprot)
-{
- pud_t *pud;
- unsigned long end;
- long cur_pages = 0;
- pgprot_t pud_pgprot;
-
- end = start + (cpa->numpages << PAGE_SHIFT);
-
- /*
- * Not on a Gb page boundary? => map everything up to it with
- * smaller pages.
- */
- if (start & (PUD_SIZE - 1)) {
- unsigned long pre_end;
- unsigned long next_page = (start + PUD_SIZE) & PUD_MASK;
-
- pre_end = min_t(unsigned long, end, next_page);
- cur_pages = (pre_end - start) >> PAGE_SHIFT;
- cur_pages = min_t(int, (int)cpa->numpages, cur_pages);
-
- pud = pud_offset(p4d, start);
-
- /*
- * Need a PMD page?
- */
- if (pud_none(*pud))
- if (alloc_pmd_page(pud))
- return -1;
-
- cur_pages = populate_pmd(cpa, start, pre_end, cur_pages,
- pud, pgprot);
- if (cur_pages < 0)
- return cur_pages;
-
- start = pre_end;
- }
-
- /* We mapped them all? */
- if (cpa->numpages == cur_pages)
- return cur_pages;
-
- pud = pud_offset(p4d, start);
- pud_pgprot = pgprot_4k_2_large(pgprot);
-
- /*
- * Map everything starting from the Gb boundary, possibly with 1G pages
- */
- while (boot_cpu_has(X86_FEATURE_GBPAGES) && end - start >= PUD_SIZE) {
- set_pud(pud, pud_mkhuge(pfn_pud(cpa->pfn,
- canon_pgprot(pud_pgprot))));
-
- start += PUD_SIZE;
- cpa->pfn += PUD_SIZE >> PAGE_SHIFT;
- cur_pages += PUD_SIZE >> PAGE_SHIFT;
- pud++;
- }
-
- /* Map trailing leftover */
- if (start < end) {
- long tmp;
-
- pud = pud_offset(p4d, start);
- if (pud_none(*pud))
- if (alloc_pmd_page(pud))
- return -1;
-
- tmp = populate_pmd(cpa, start, end, cpa->numpages - cur_pages,
- pud, pgprot);
- if (tmp < 0)
- return cur_pages;
-
- cur_pages += tmp;
- }
- return cur_pages;
-}
-
-/*
- * Restrictions for kernel page table do not necessarily apply when mapping in
- * an alternate PGD.
- */
-static int populate_pgd(struct cpa_data *cpa, unsigned long addr)
-{
- pgprot_t pgprot = __pgprot(_KERNPG_TABLE);
- pud_t *pud = NULL; /* shut up gcc */
- p4d_t *p4d;
- pgd_t *pgd_entry;
- long ret;
-
- pgd_entry = cpa->pgd + pgd_index(addr);
-
- if (pgd_none(*pgd_entry)) {
- p4d = (p4d_t *)get_zeroed_page(GFP_KERNEL);
- if (!p4d)
- return -1;
-
- set_pgd(pgd_entry, __pgd(__pa(p4d) | _KERNPG_TABLE));
- }
-
- /*
- * Allocate a PUD page and hand it down for mapping.
- */
- p4d = p4d_offset(pgd_entry, addr);
- if (p4d_none(*p4d)) {
- pud = (pud_t *)get_zeroed_page(GFP_KERNEL);
- if (!pud)
- return -1;
-
- set_p4d(p4d, __p4d(__pa(pud) | _KERNPG_TABLE));
- }
-
- pgprot_val(pgprot) &= ~pgprot_val(cpa->mask_clr);
- pgprot_val(pgprot) |= pgprot_val(cpa->mask_set);
-
- ret = populate_pud(cpa, addr, p4d, pgprot);
- if (ret < 0) {
- /*
- * Leave the PUD page in place in case some other CPU or thread
- * already found it, but remove any useless entries we just
- * added to it.
- */
- unmap_pud_range(p4d, addr,
- addr + (cpa->numpages << PAGE_SHIFT));
- return ret;
- }
-
- cpa->numpages = ret;
- return 0;
-}
-
-static int __cpa_process_fault(struct cpa_data *cpa, unsigned long vaddr,
- int primary)
-{
- if (cpa->pgd) {
- /*
- * Right now, we only execute this code path when mapping
- * the EFI virtual memory map regions, no other users
- * provide a ->pgd value. This may change in the future.
- */
- return populate_pgd(cpa, vaddr);
- }
-
- /*
- * Ignore all non primary paths.
- */
- if (!primary) {
- cpa->numpages = 1;
- return 0;
- }
-
- /*
- * Ignore the NULL PTE for kernel identity mapping, as it is expected
- * to have holes.
- * Also set numpages to '1' indicating that we processed cpa req for
- * one virtual address page and its pfn. TBD: numpages can be set based
- * on the initial value and the level returned by lookup_address().
- */
- if (within(vaddr, PAGE_OFFSET,
- PAGE_OFFSET + (max_pfn_mapped << PAGE_SHIFT))) {
- cpa->numpages = 1;
- cpa->pfn = __pa(vaddr) >> PAGE_SHIFT;
- return 0;
-
- } else if (__cpa_pfn_in_highmap(cpa->pfn)) {
- /* Faults in the highmap are OK, so do not warn: */
- return -EFAULT;
- } else {
- WARN(1, KERN_WARNING "CPA: called for zero pte. "
- "vaddr = %lx cpa->vaddr = %lx\n", vaddr,
- *cpa->vaddr);
-
- return -EFAULT;
- }
-}
-
-static int __change_page_attr(struct cpa_data *cpa, int primary)
-{
- unsigned long address;
- int do_split, err;
- unsigned int level;
- pte_t *kpte, old_pte;
-
- address = __cpa_addr(cpa, cpa->curpage);
-repeat:
- kpte = _lookup_address_cpa(cpa, address, &level);
- if (!kpte)
- return __cpa_process_fault(cpa, address, primary);
-
- old_pte = *kpte;
- if (pte_none(old_pte))
- return __cpa_process_fault(cpa, address, primary);
-
- if (level == PG_LEVEL_4K) {
- pte_t new_pte;
- pgprot_t new_prot = pte_pgprot(old_pte);
- unsigned long pfn = pte_pfn(old_pte);
-
- pgprot_val(new_prot) &= ~pgprot_val(cpa->mask_clr);
- pgprot_val(new_prot) |= pgprot_val(cpa->mask_set);
-
- cpa_inc_4k_install();
- /* Hand in lpsize = 0 to enforce the protection mechanism */
- new_prot = static_protections(new_prot, address, pfn, 1, 0,
- CPA_PROTECT);
-
- new_prot = pgprot_clear_protnone_bits(new_prot);
-
- /*
- * We need to keep the pfn from the existing PTE,
- * after all we're only going to change it's attributes
- * not the memory it points to
- */
- new_pte = pfn_pte(pfn, new_prot);
- cpa->pfn = pfn;
- /*
- * Do we really change anything ?
- */
- if (pte_val(old_pte) != pte_val(new_pte)) {
- set_pte_atomic(kpte, new_pte);
- cpa->flags |= CPA_FLUSHTLB;
- }
- cpa->numpages = 1;
- return 0;
- }
-
- /*
- * Check, whether we can keep the large page intact
- * and just change the pte:
- */
- do_split = should_split_large_page(kpte, address, cpa);
- /*
- * When the range fits into the existing large page,
- * return. cp->numpages and cpa->tlbflush have been updated in
- * try_large_page:
- */
- if (do_split <= 0)
- return do_split;
-
- /*
- * We have to split the large page:
- */
- err = split_large_page(cpa, kpte, address);
- if (!err)
- goto repeat;
-
- return err;
-}
-
-static int __change_page_attr_set_clr(struct cpa_data *cpa, int checkalias);
-
-static int cpa_process_alias(struct cpa_data *cpa)
-{
- struct cpa_data alias_cpa;
- unsigned long laddr = (unsigned long)__va(cpa->pfn << PAGE_SHIFT);
- unsigned long vaddr;
- int ret;
-
- if (!pfn_range_is_mapped(cpa->pfn, cpa->pfn + 1))
- return 0;
-
- /*
- * No need to redo, when the primary call touched the direct
- * mapping already:
- */
- vaddr = __cpa_addr(cpa, cpa->curpage);
- if (!(within(vaddr, PAGE_OFFSET,
- PAGE_OFFSET + (max_pfn_mapped << PAGE_SHIFT)))) {
-
- alias_cpa = *cpa;
- alias_cpa.vaddr = &laddr;
- alias_cpa.flags &= ~(CPA_PAGES_ARRAY | CPA_ARRAY);
- alias_cpa.curpage = 0;
-
- ret = __change_page_attr_set_clr(&alias_cpa, 0);
- if (ret)
- return ret;
- }
-
-#ifdef CONFIG_X86_64
- /*
- * If the primary call didn't touch the high mapping already
- * and the physical address is inside the kernel map, we need
- * to touch the high mapped kernel as well:
- */
- if (!within(vaddr, (unsigned long)_text, _brk_end) &&
- __cpa_pfn_in_highmap(cpa->pfn)) {
- unsigned long temp_cpa_vaddr = (cpa->pfn << PAGE_SHIFT) +
- __START_KERNEL_map - phys_base;
- alias_cpa = *cpa;
- alias_cpa.vaddr = &temp_cpa_vaddr;
- alias_cpa.flags &= ~(CPA_PAGES_ARRAY | CPA_ARRAY);
- alias_cpa.curpage = 0;
-
- /*
- * The high mapping range is imprecise, so ignore the
- * return value.
- */
- __change_page_attr_set_clr(&alias_cpa, 0);
- }
-#endif
-
- return 0;
-}
-
-static int __change_page_attr_set_clr(struct cpa_data *cpa, int checkalias)
-{
- unsigned long numpages = cpa->numpages;
- unsigned long rempages = numpages;
- int ret = 0;
-
- while (rempages) {
- /*
- * Store the remaining nr of pages for the large page
- * preservation check.
- */
- cpa->numpages = rempages;
- /* for array changes, we can't use large page */
- if (cpa->flags & (CPA_ARRAY | CPA_PAGES_ARRAY))
- cpa->numpages = 1;
-
- if (!debug_pagealloc_enabled())
- spin_lock(&cpa_lock);
- ret = __change_page_attr(cpa, checkalias);
- if (!debug_pagealloc_enabled())
- spin_unlock(&cpa_lock);
- if (ret)
- goto out;
-
- if (checkalias) {
- ret = cpa_process_alias(cpa);
- if (ret)
- goto out;
- }
-
- /*
- * Adjust the number of pages with the result of the
- * CPA operation. Either a large page has been
- * preserved or a single page update happened.
- */
- BUG_ON(cpa->numpages > rempages || !cpa->numpages);
- rempages -= cpa->numpages;
- cpa->curpage += cpa->numpages;
- }
-
-out:
- /* Restore the original numpages */
- cpa->numpages = numpages;
- return ret;
-}
-
-static int change_page_attr_set_clr(unsigned long *addr, int numpages,
- pgprot_t mask_set, pgprot_t mask_clr,
- int force_split, int in_flag,
- struct page **pages)
-{
- struct cpa_data cpa;
- int ret, cache, checkalias;
-
- memset(&cpa, 0, sizeof(cpa));
-
- /*
- * Check, if we are requested to set a not supported
- * feature. Clearing non-supported features is OK.
- */
- mask_set = canon_pgprot(mask_set);
-
- if (!pgprot_val(mask_set) && !pgprot_val(mask_clr) && !force_split)
- return 0;
-
- /* Ensure we are PAGE_SIZE aligned */
- if (in_flag & CPA_ARRAY) {
- int i;
- for (i = 0; i < numpages; i++) {
- if (addr[i] & ~PAGE_MASK) {
- addr[i] &= PAGE_MASK;
- WARN_ON_ONCE(1);
- }
- }
- } else if (!(in_flag & CPA_PAGES_ARRAY)) {
- /*
- * in_flag of CPA_PAGES_ARRAY implies it is aligned.
- * No need to check in that case
- */
- if (*addr & ~PAGE_MASK) {
- *addr &= PAGE_MASK;
- /*
- * People should not be passing in unaligned addresses:
- */
- WARN_ON_ONCE(1);
- }
- }
-
- /* Must avoid aliasing mappings in the highmem code */
- kmap_flush_unused();
-
- vm_unmap_aliases();
-
- cpa.vaddr = addr;
- cpa.pages = pages;
- cpa.numpages = numpages;
- cpa.mask_set = mask_set;
- cpa.mask_clr = mask_clr;
- cpa.flags = 0;
- cpa.curpage = 0;
- cpa.force_split = force_split;
-
- if (in_flag & (CPA_ARRAY | CPA_PAGES_ARRAY))
- cpa.flags |= in_flag;
-
- /* No alias checking for _NX bit modifications */
- checkalias = (pgprot_val(mask_set) | pgprot_val(mask_clr)) != _PAGE_NX;
- /* Has caller explicitly disabled alias checking? */
- if (in_flag & CPA_NO_CHECK_ALIAS)
- checkalias = 0;
-
- ret = __change_page_attr_set_clr(&cpa, checkalias);
-
- /*
- * Check whether we really changed something:
- */
- if (!(cpa.flags & CPA_FLUSHTLB))
- goto out;
-
- /*
- * No need to flush, when we did not set any of the caching
- * attributes:
- */
- cache = !!pgprot2cachemode(mask_set);
-
- /*
- * On error; flush everything to be sure.
- */
- if (ret) {
- cpa_flush_all(cache);
- goto out;
- }
-
- cpa_flush(&cpa, cache);
-out:
- return ret;
-}
-
-static inline int change_page_attr_set(unsigned long *addr, int numpages,
- pgprot_t mask, int array)
-{
- return change_page_attr_set_clr(addr, numpages, mask, __pgprot(0), 0,
- (array ? CPA_ARRAY : 0), NULL);
-}
-
-static inline int change_page_attr_clear(unsigned long *addr, int numpages,
- pgprot_t mask, int array)
-{
- return change_page_attr_set_clr(addr, numpages, __pgprot(0), mask, 0,
- (array ? CPA_ARRAY : 0), NULL);
-}
-
-static inline int cpa_set_pages_array(struct page **pages, int numpages,
- pgprot_t mask)
-{
- return change_page_attr_set_clr(NULL, numpages, mask, __pgprot(0), 0,
- CPA_PAGES_ARRAY, pages);
-}
-
-static inline int cpa_clear_pages_array(struct page **pages, int numpages,
- pgprot_t mask)
-{
- return change_page_attr_set_clr(NULL, numpages, __pgprot(0), mask, 0,
- CPA_PAGES_ARRAY, pages);
-}
-
-int _set_memory_uc(unsigned long addr, int numpages)
-{
- /*
- * for now UC MINUS. see comments in ioremap()
- * If you really need strong UC use ioremap_uc(), but note
- * that you cannot override IO areas with set_memory_*() as
- * these helpers cannot work with IO memory.
- */
- return change_page_attr_set(&addr, numpages,
- cachemode2pgprot(_PAGE_CACHE_MODE_UC_MINUS),
- 0);
-}
-
-int set_memory_uc(unsigned long addr, int numpages)
-{
- int ret;
-
- /*
- * for now UC MINUS. see comments in ioremap()
- */
- ret = reserve_memtype(__pa(addr), __pa(addr) + numpages * PAGE_SIZE,
- _PAGE_CACHE_MODE_UC_MINUS, NULL);
- if (ret)
- goto out_err;
-
- ret = _set_memory_uc(addr, numpages);
- if (ret)
- goto out_free;
-
- return 0;
-
-out_free:
- free_memtype(__pa(addr), __pa(addr) + numpages * PAGE_SIZE);
-out_err:
- return ret;
-}
-EXPORT_SYMBOL(set_memory_uc);
-
-int _set_memory_wc(unsigned long addr, int numpages)
-{
- int ret;
-
- ret = change_page_attr_set(&addr, numpages,
- cachemode2pgprot(_PAGE_CACHE_MODE_UC_MINUS),
- 0);
- if (!ret) {
- ret = change_page_attr_set_clr(&addr, numpages,
- cachemode2pgprot(_PAGE_CACHE_MODE_WC),
- __pgprot(_PAGE_CACHE_MASK),
- 0, 0, NULL);
- }
- return ret;
-}
-
-int set_memory_wc(unsigned long addr, int numpages)
-{
- int ret;
-
- ret = reserve_memtype(__pa(addr), __pa(addr) + numpages * PAGE_SIZE,
- _PAGE_CACHE_MODE_WC, NULL);
- if (ret)
- return ret;
-
- ret = _set_memory_wc(addr, numpages);
- if (ret)
- free_memtype(__pa(addr), __pa(addr) + numpages * PAGE_SIZE);
-
- return ret;
-}
-EXPORT_SYMBOL(set_memory_wc);
-
-int _set_memory_wt(unsigned long addr, int numpages)
-{
- return change_page_attr_set(&addr, numpages,
- cachemode2pgprot(_PAGE_CACHE_MODE_WT), 0);
-}
-
-int _set_memory_wb(unsigned long addr, int numpages)
-{
- /* WB cache mode is hard wired to all cache attribute bits being 0 */
- return change_page_attr_clear(&addr, numpages,
- __pgprot(_PAGE_CACHE_MASK), 0);
-}
-
-int set_memory_wb(unsigned long addr, int numpages)
-{
- int ret;
-
- ret = _set_memory_wb(addr, numpages);
- if (ret)
- return ret;
-
- free_memtype(__pa(addr), __pa(addr) + numpages * PAGE_SIZE);
- return 0;
-}
-EXPORT_SYMBOL(set_memory_wb);
-
-int set_memory_x(unsigned long addr, int numpages)
-{
- if (!(__supported_pte_mask & _PAGE_NX))
- return 0;
-
- return change_page_attr_clear(&addr, numpages, __pgprot(_PAGE_NX), 0);
-}
-
-int set_memory_nx(unsigned long addr, int numpages)
-{
- if (!(__supported_pte_mask & _PAGE_NX))
- return 0;
-
- return change_page_attr_set(&addr, numpages, __pgprot(_PAGE_NX), 0);
-}
-
-int set_memory_ro(unsigned long addr, int numpages)
-{
- return change_page_attr_clear(&addr, numpages, __pgprot(_PAGE_RW), 0);
-}
-
-int set_memory_rw(unsigned long addr, int numpages)
-{
- return change_page_attr_set(&addr, numpages, __pgprot(_PAGE_RW), 0);
-}
-
-int set_memory_np(unsigned long addr, int numpages)
-{
- return change_page_attr_clear(&addr, numpages, __pgprot(_PAGE_PRESENT), 0);
-}
-
-int set_memory_np_noalias(unsigned long addr, int numpages)
-{
- int cpa_flags = CPA_NO_CHECK_ALIAS;
-
- return change_page_attr_set_clr(&addr, numpages, __pgprot(0),
- __pgprot(_PAGE_PRESENT), 0,
- cpa_flags, NULL);
-}
-
-int set_memory_4k(unsigned long addr, int numpages)
-{
- return change_page_attr_set_clr(&addr, numpages, __pgprot(0),
- __pgprot(0), 1, 0, NULL);
-}
-
-int set_memory_nonglobal(unsigned long addr, int numpages)
-{
- return change_page_attr_clear(&addr, numpages,
- __pgprot(_PAGE_GLOBAL), 0);
-}
-
-int set_memory_global(unsigned long addr, int numpages)
-{
- return change_page_attr_set(&addr, numpages,
- __pgprot(_PAGE_GLOBAL), 0);
-}
-
-static int __set_memory_enc_dec(unsigned long addr, int numpages, bool enc)
-{
- struct cpa_data cpa;
- int ret;
-
- /* Nothing to do if memory encryption is not active */
- if (!mem_encrypt_active())
- return 0;
-
- /* Should not be working on unaligned addresses */
- if (WARN_ONCE(addr & ~PAGE_MASK, "misaligned address: %#lx\n", addr))
- addr &= PAGE_MASK;
-
- memset(&cpa, 0, sizeof(cpa));
- cpa.vaddr = &addr;
- cpa.numpages = numpages;
- cpa.mask_set = enc ? __pgprot(_PAGE_ENC) : __pgprot(0);
- cpa.mask_clr = enc ? __pgprot(0) : __pgprot(_PAGE_ENC);
- cpa.pgd = init_mm.pgd;
-
- /* Must avoid aliasing mappings in the highmem code */
- kmap_flush_unused();
- vm_unmap_aliases();
-
- /*
- * Before changing the encryption attribute, we need to flush caches.
- */
- cpa_flush(&cpa, 1);
-
- ret = __change_page_attr_set_clr(&cpa, 1);
-
- /*
- * After changing the encryption attribute, we need to flush TLBs again
- * in case any speculative TLB caching occurred (but no need to flush
- * caches again). We could just use cpa_flush_all(), but in case TLB
- * flushing gets optimized in the cpa_flush() path use the same logic
- * as above.
- */
- cpa_flush(&cpa, 0);
-
- return ret;
-}
-
-int set_memory_encrypted(unsigned long addr, int numpages)
-{
- return __set_memory_enc_dec(addr, numpages, true);
-}
-EXPORT_SYMBOL_GPL(set_memory_encrypted);
-
-int set_memory_decrypted(unsigned long addr, int numpages)
-{
- return __set_memory_enc_dec(addr, numpages, false);
-}
-EXPORT_SYMBOL_GPL(set_memory_decrypted);
-
-int set_pages_uc(struct page *page, int numpages)
-{
- unsigned long addr = (unsigned long)page_address(page);
-
- return set_memory_uc(addr, numpages);
-}
-EXPORT_SYMBOL(set_pages_uc);
-
-static int _set_pages_array(struct page **pages, int numpages,
- enum page_cache_mode new_type)
-{
- unsigned long start;
- unsigned long end;
- enum page_cache_mode set_type;
- int i;
- int free_idx;
- int ret;
-
- for (i = 0; i < numpages; i++) {
- if (PageHighMem(pages[i]))
- continue;
- start = page_to_pfn(pages[i]) << PAGE_SHIFT;
- end = start + PAGE_SIZE;
- if (reserve_memtype(start, end, new_type, NULL))
- goto err_out;
- }
-
- /* If WC, set to UC- first and then WC */
- set_type = (new_type == _PAGE_CACHE_MODE_WC) ?
- _PAGE_CACHE_MODE_UC_MINUS : new_type;
-
- ret = cpa_set_pages_array(pages, numpages,
- cachemode2pgprot(set_type));
- if (!ret && new_type == _PAGE_CACHE_MODE_WC)
- ret = change_page_attr_set_clr(NULL, numpages,
- cachemode2pgprot(
- _PAGE_CACHE_MODE_WC),
- __pgprot(_PAGE_CACHE_MASK),
- 0, CPA_PAGES_ARRAY, pages);
- if (ret)
- goto err_out;
- return 0; /* Success */
-err_out:
- free_idx = i;
- for (i = 0; i < free_idx; i++) {
- if (PageHighMem(pages[i]))
- continue;
- start = page_to_pfn(pages[i]) << PAGE_SHIFT;
- end = start + PAGE_SIZE;
- free_memtype(start, end);
- }
- return -EINVAL;
-}
-
-int set_pages_array_uc(struct page **pages, int numpages)
-{
- return _set_pages_array(pages, numpages, _PAGE_CACHE_MODE_UC_MINUS);
-}
-EXPORT_SYMBOL(set_pages_array_uc);
-
-int set_pages_array_wc(struct page **pages, int numpages)
-{
- return _set_pages_array(pages, numpages, _PAGE_CACHE_MODE_WC);
-}
-EXPORT_SYMBOL(set_pages_array_wc);
-
-int set_pages_array_wt(struct page **pages, int numpages)
-{
- return _set_pages_array(pages, numpages, _PAGE_CACHE_MODE_WT);
-}
-EXPORT_SYMBOL_GPL(set_pages_array_wt);
-
-int set_pages_wb(struct page *page, int numpages)
-{
- unsigned long addr = (unsigned long)page_address(page);
-
- return set_memory_wb(addr, numpages);
-}
-EXPORT_SYMBOL(set_pages_wb);
-
-int set_pages_array_wb(struct page **pages, int numpages)
-{
- int retval;
- unsigned long start;
- unsigned long end;
- int i;
-
- /* WB cache mode is hard wired to all cache attribute bits being 0 */
- retval = cpa_clear_pages_array(pages, numpages,
- __pgprot(_PAGE_CACHE_MASK));
- if (retval)
- return retval;
-
- for (i = 0; i < numpages; i++) {
- if (PageHighMem(pages[i]))
- continue;
- start = page_to_pfn(pages[i]) << PAGE_SHIFT;
- end = start + PAGE_SIZE;
- free_memtype(start, end);
- }
-
- return 0;
-}
-EXPORT_SYMBOL(set_pages_array_wb);
-
-int set_pages_ro(struct page *page, int numpages)
-{
- unsigned long addr = (unsigned long)page_address(page);
-
- return set_memory_ro(addr, numpages);
-}
-
-int set_pages_rw(struct page *page, int numpages)
-{
- unsigned long addr = (unsigned long)page_address(page);
-
- return set_memory_rw(addr, numpages);
-}
-
-static int __set_pages_p(struct page *page, int numpages)
-{
- unsigned long tempaddr = (unsigned long) page_address(page);
- struct cpa_data cpa = { .vaddr = &tempaddr,
- .pgd = NULL,
- .numpages = numpages,
- .mask_set = __pgprot(_PAGE_PRESENT | _PAGE_RW),
- .mask_clr = __pgprot(0),
- .flags = 0};
-
- /*
- * No alias checking needed for setting present flag. otherwise,
- * we may need to break large pages for 64-bit kernel text
- * mappings (this adds to complexity if we want to do this from
- * atomic context especially). Let's keep it simple!
- */
- return __change_page_attr_set_clr(&cpa, 0);
-}
-
-static int __set_pages_np(struct page *page, int numpages)
-{
- unsigned long tempaddr = (unsigned long) page_address(page);
- struct cpa_data cpa = { .vaddr = &tempaddr,
- .pgd = NULL,
- .numpages = numpages,
- .mask_set = __pgprot(0),
- .mask_clr = __pgprot(_PAGE_PRESENT | _PAGE_RW),
- .flags = 0};
-
- /*
- * No alias checking needed for setting not present flag. otherwise,
- * we may need to break large pages for 64-bit kernel text
- * mappings (this adds to complexity if we want to do this from
- * atomic context especially). Let's keep it simple!
- */
- return __change_page_attr_set_clr(&cpa, 0);
-}
-
-int set_direct_map_invalid_noflush(struct page *page)
-{
- return __set_pages_np(page, 1);
-}
-
-int set_direct_map_default_noflush(struct page *page)
-{
- return __set_pages_p(page, 1);
-}
-
-void __kernel_map_pages(struct page *page, int numpages, int enable)
-{
- if (PageHighMem(page))
- return;
- if (!enable) {
- debug_check_no_locks_freed(page_address(page),
- numpages * PAGE_SIZE);
- }
-
- /*
- * The return value is ignored as the calls cannot fail.
- * Large pages for identity mappings are not used at boot time
- * and hence no memory allocations during large page split.
- */
- if (enable)
- __set_pages_p(page, numpages);
- else
- __set_pages_np(page, numpages);
-
- /*
- * We should perform an IPI and flush all tlbs,
- * but that can deadlock->flush only current cpu.
- * Preemption needs to be disabled around __flush_tlb_all() due to
- * CR3 reload in __native_flush_tlb().
- */
- preempt_disable();
- __flush_tlb_all();
- preempt_enable();
-
- arch_flush_lazy_mmu_mode();
-}
-
-#ifdef CONFIG_HIBERNATION
-bool kernel_page_present(struct page *page)
-{
- unsigned int level;
- pte_t *pte;
-
- if (PageHighMem(page))
- return false;
-
- pte = lookup_address((unsigned long)page_address(page), &level);
- return (pte_val(*pte) & _PAGE_PRESENT);
-}
-#endif /* CONFIG_HIBERNATION */
-
-int __init kernel_map_pages_in_pgd(pgd_t *pgd, u64 pfn, unsigned long address,
- unsigned numpages, unsigned long page_flags)
-{
- int retval = -EINVAL;
-
- struct cpa_data cpa = {
- .vaddr = &address,
- .pfn = pfn,
- .pgd = pgd,
- .numpages = numpages,
- .mask_set = __pgprot(0),
- .mask_clr = __pgprot(0),
- .flags = 0,
- };
-
- WARN_ONCE(num_online_cpus() > 1, "Don't call after initializing SMP");
-
- if (!(__supported_pte_mask & _PAGE_NX))
- goto out;
-
- if (!(page_flags & _PAGE_NX))
- cpa.mask_clr = __pgprot(_PAGE_NX);
-
- if (!(page_flags & _PAGE_RW))
- cpa.mask_clr = __pgprot(_PAGE_RW);
-
- if (!(page_flags & _PAGE_ENC))
- cpa.mask_clr = pgprot_encrypted(cpa.mask_clr);
-
- cpa.mask_set = __pgprot(_PAGE_PRESENT | page_flags);
-
- retval = __change_page_attr_set_clr(&cpa, 0);
- __flush_tlb_all();
-
-out:
- return retval;
-}
-
-/*
- * __flush_tlb_all() flushes mappings only on current CPU and hence this
- * function shouldn't be used in an SMP environment. Presently, it's used only
- * during boot (way before smp_init()) by EFI subsystem and hence is ok.
- */
-int __init kernel_unmap_pages_in_pgd(pgd_t *pgd, unsigned long address,
- unsigned long numpages)
-{
- int retval;
-
- /*
- * The typical sequence for unmapping is to find a pte through
- * lookup_address_in_pgd() (ideally, it should never return NULL because
- * the address is already mapped) and change it's protections. As pfn is
- * the *target* of a mapping, it's not useful while unmapping.
- */
- struct cpa_data cpa = {
- .vaddr = &address,
- .pfn = 0,
- .pgd = pgd,
- .numpages = numpages,
- .mask_set = __pgprot(0),
- .mask_clr = __pgprot(_PAGE_PRESENT | _PAGE_RW),
- .flags = 0,
- };
-
- WARN_ONCE(num_online_cpus() > 1, "Don't call after initializing SMP");
-
- retval = __change_page_attr_set_clr(&cpa, 0);
- __flush_tlb_all();
-
- return retval;
-}
-
-/*
- * The testcases use internal knowledge of the implementation that shouldn't
- * be exposed to the rest of the kernel. Include these directly here.
- */
-#ifdef CONFIG_CPA_DEBUG
-#include "pageattr-test.c"
-#endif
diff --git a/arch/x86/mm/pat.c b/arch/x86/mm/pat.c
deleted file mode 100644
index f1677fa..0000000
--- a/arch/x86/mm/pat.c
+++ /dev/null
@@ -1,1219 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0-only
-/*
- * Page Attribute Table (PAT) support: handle memory caching attributes in page tables.
- *
- * Authors: Venkatesh Pallipadi <venkatesh.pallipadi@...el.com>
- * Suresh B Siddha <suresh.b.siddha@...el.com>
- *
- * Loosely based on earlier PAT patchset from Eric Biederman and Andi Kleen.
- *
- * Basic principles:
- *
- * PAT is a CPU feature supported by all modern x86 CPUs, to allow the firmware and
- * the kernel to set one of a handful of 'caching type' attributes for physical
- * memory ranges: uncached, write-combining, write-through, write-protected,
- * and the most commonly used and default attribute: write-back caching.
- *
- * PAT support supercedes and augments MTRR support in a compatible fashion: MTRR is
- * a hardware interface to enumerate a limited number of physical memory ranges
- * and set their caching attributes explicitly, programmed into the CPU via MSRs.
- * Even modern CPUs have MTRRs enabled - but these are typically not touched
- * by the kernel or by user-space (such as the X server), we rely on PAT for any
- * additional cache attribute logic.
- *
- * PAT doesn't work via explicit memory ranges, but uses page table entries to add
- * cache attribute information to the mapped memory range: there's 3 bits used,
- * (_PAGE_PWT, _PAGE_PCD, _PAGE_PAT), with the 8 possible values mapped by the
- * CPU to actual cache attributes via an MSR loaded into the CPU (MSR_IA32_CR_PAT).
- *
- * ( There's a metric ton of finer details, such as compatibility with CPU quirks
- * that only support 4 types of PAT entries, and interaction with MTRRs, see
- * below for details. )
- */
-
-#include <linux/seq_file.h>
-#include <linux/memblock.h>
-#include <linux/debugfs.h>
-#include <linux/ioport.h>
-#include <linux/kernel.h>
-#include <linux/pfn_t.h>
-#include <linux/slab.h>
-#include <linux/mm.h>
-#include <linux/fs.h>
-#include <linux/rbtree.h>
-
-#include <asm/cacheflush.h>
-#include <asm/processor.h>
-#include <asm/tlbflush.h>
-#include <asm/x86_init.h>
-#include <asm/pgtable.h>
-#include <asm/fcntl.h>
-#include <asm/e820/api.h>
-#include <asm/mtrr.h>
-#include <asm/page.h>
-#include <asm/msr.h>
-#include <asm/pat.h>
-#include <asm/io.h>
-
-#include "pat_internal.h"
-#include "mm_internal.h"
-
-#undef pr_fmt
-#define pr_fmt(fmt) "" fmt
-
-static bool __read_mostly pat_bp_initialized;
-static bool __read_mostly pat_disabled = !IS_ENABLED(CONFIG_X86_PAT);
-static bool __read_mostly pat_bp_enabled;
-static bool __read_mostly pat_cm_initialized;
-
-/*
- * PAT support is enabled by default, but can be disabled for
- * various user-requested or hardware-forced reasons:
- */
-void pat_disable(const char *msg_reason)
-{
- if (pat_disabled)
- return;
-
- if (pat_bp_initialized) {
- WARN_ONCE(1, "x86/PAT: PAT cannot be disabled after initialization\n");
- return;
- }
-
- pat_disabled = true;
- pr_info("x86/PAT: %s\n", msg_reason);
-}
-
-static int __init nopat(char *str)
-{
- pat_disable("PAT support disabled via boot option.");
- return 0;
-}
-early_param("nopat", nopat);
-
-bool pat_enabled(void)
-{
- return pat_bp_enabled;
-}
-EXPORT_SYMBOL_GPL(pat_enabled);
-
-int pat_debug_enable;
-
-static int __init pat_debug_setup(char *str)
-{
- pat_debug_enable = 1;
- return 0;
-}
-__setup("debugpat", pat_debug_setup);
-
-#ifdef CONFIG_X86_PAT
-/*
- * X86 PAT uses page flags arch_1 and uncached together to keep track of
- * memory type of pages that have backing page struct.
- *
- * X86 PAT supports 4 different memory types:
- * - _PAGE_CACHE_MODE_WB
- * - _PAGE_CACHE_MODE_WC
- * - _PAGE_CACHE_MODE_UC_MINUS
- * - _PAGE_CACHE_MODE_WT
- *
- * _PAGE_CACHE_MODE_WB is the default type.
- */
-
-#define _PGMT_WB 0
-#define _PGMT_WC (1UL << PG_arch_1)
-#define _PGMT_UC_MINUS (1UL << PG_uncached)
-#define _PGMT_WT (1UL << PG_uncached | 1UL << PG_arch_1)
-#define _PGMT_MASK (1UL << PG_uncached | 1UL << PG_arch_1)
-#define _PGMT_CLEAR_MASK (~_PGMT_MASK)
-
-static inline enum page_cache_mode get_page_memtype(struct page *pg)
-{
- unsigned long pg_flags = pg->flags & _PGMT_MASK;
-
- if (pg_flags == _PGMT_WB)
- return _PAGE_CACHE_MODE_WB;
- else if (pg_flags == _PGMT_WC)
- return _PAGE_CACHE_MODE_WC;
- else if (pg_flags == _PGMT_UC_MINUS)
- return _PAGE_CACHE_MODE_UC_MINUS;
- else
- return _PAGE_CACHE_MODE_WT;
-}
-
-static inline void set_page_memtype(struct page *pg,
- enum page_cache_mode memtype)
-{
- unsigned long memtype_flags;
- unsigned long old_flags;
- unsigned long new_flags;
-
- switch (memtype) {
- case _PAGE_CACHE_MODE_WC:
- memtype_flags = _PGMT_WC;
- break;
- case _PAGE_CACHE_MODE_UC_MINUS:
- memtype_flags = _PGMT_UC_MINUS;
- break;
- case _PAGE_CACHE_MODE_WT:
- memtype_flags = _PGMT_WT;
- break;
- case _PAGE_CACHE_MODE_WB:
- default:
- memtype_flags = _PGMT_WB;
- break;
- }
-
- do {
- old_flags = pg->flags;
- new_flags = (old_flags & _PGMT_CLEAR_MASK) | memtype_flags;
- } while (cmpxchg(&pg->flags, old_flags, new_flags) != old_flags);
-}
-#else
-static inline enum page_cache_mode get_page_memtype(struct page *pg)
-{
- return -1;
-}
-static inline void set_page_memtype(struct page *pg,
- enum page_cache_mode memtype)
-{
-}
-#endif
-
-enum {
- PAT_UC = 0, /* uncached */
- PAT_WC = 1, /* Write combining */
- PAT_WT = 4, /* Write Through */
- PAT_WP = 5, /* Write Protected */
- PAT_WB = 6, /* Write Back (default) */
- PAT_UC_MINUS = 7, /* UC, but can be overridden by MTRR */
-};
-
-#define CM(c) (_PAGE_CACHE_MODE_ ## c)
-
-static enum page_cache_mode pat_get_cache_mode(unsigned pat_val, char *msg)
-{
- enum page_cache_mode cache;
- char *cache_mode;
-
- switch (pat_val) {
- case PAT_UC: cache = CM(UC); cache_mode = "UC "; break;
- case PAT_WC: cache = CM(WC); cache_mode = "WC "; break;
- case PAT_WT: cache = CM(WT); cache_mode = "WT "; break;
- case PAT_WP: cache = CM(WP); cache_mode = "WP "; break;
- case PAT_WB: cache = CM(WB); cache_mode = "WB "; break;
- case PAT_UC_MINUS: cache = CM(UC_MINUS); cache_mode = "UC- "; break;
- default: cache = CM(WB); cache_mode = "WB "; break;
- }
-
- memcpy(msg, cache_mode, 4);
-
- return cache;
-}
-
-#undef CM
-
-/*
- * Update the cache mode to pgprot translation tables according to PAT
- * configuration.
- * Using lower indices is preferred, so we start with highest index.
- */
-static void __init_cache_modes(u64 pat)
-{
- enum page_cache_mode cache;
- char pat_msg[33];
- int i;
-
- WARN_ON_ONCE(pat_cm_initialized);
-
- pat_msg[32] = 0;
- for (i = 7; i >= 0; i--) {
- cache = pat_get_cache_mode((pat >> (i * 8)) & 7,
- pat_msg + 4 * i);
- update_cache_mode_entry(i, cache);
- }
- pr_info("x86/PAT: Configuration [0-7]: %s\n", pat_msg);
-
- pat_cm_initialized = true;
-}
-
-#define PAT(x, y) ((u64)PAT_ ## y << ((x)*8))
-
-static void pat_bp_init(u64 pat)
-{
- u64 tmp_pat;
-
- if (!boot_cpu_has(X86_FEATURE_PAT)) {
- pat_disable("PAT not supported by the CPU.");
- return;
- }
-
- rdmsrl(MSR_IA32_CR_PAT, tmp_pat);
- if (!tmp_pat) {
- pat_disable("PAT support disabled by the firmware.");
- return;
- }
-
- wrmsrl(MSR_IA32_CR_PAT, pat);
- pat_bp_enabled = true;
-
- __init_cache_modes(pat);
-}
-
-static void pat_ap_init(u64 pat)
-{
- if (!boot_cpu_has(X86_FEATURE_PAT)) {
- /*
- * If this happens we are on a secondary CPU, but switched to
- * PAT on the boot CPU. We have no way to undo PAT.
- */
- panic("x86/PAT: PAT enabled, but not supported by secondary CPU\n");
- }
-
- wrmsrl(MSR_IA32_CR_PAT, pat);
-}
-
-void init_cache_modes(void)
-{
- u64 pat = 0;
-
- if (pat_cm_initialized)
- return;
-
- if (boot_cpu_has(X86_FEATURE_PAT)) {
- /*
- * CPU supports PAT. Set PAT table to be consistent with
- * PAT MSR. This case supports "nopat" boot option, and
- * virtual machine environments which support PAT without
- * MTRRs. In specific, Xen has unique setup to PAT MSR.
- *
- * If PAT MSR returns 0, it is considered invalid and emulates
- * as No PAT.
- */
- rdmsrl(MSR_IA32_CR_PAT, pat);
- }
-
- if (!pat) {
- /*
- * No PAT. Emulate the PAT table that corresponds to the two
- * cache bits, PWT (Write Through) and PCD (Cache Disable).
- * This setup is also the same as the BIOS default setup.
- *
- * PTE encoding:
- *
- * PCD
- * |PWT PAT
- * || slot
- * 00 0 WB : _PAGE_CACHE_MODE_WB
- * 01 1 WT : _PAGE_CACHE_MODE_WT
- * 10 2 UC-: _PAGE_CACHE_MODE_UC_MINUS
- * 11 3 UC : _PAGE_CACHE_MODE_UC
- *
- * NOTE: When WC or WP is used, it is redirected to UC- per
- * the default setup in __cachemode2pte_tbl[].
- */
- pat = PAT(0, WB) | PAT(1, WT) | PAT(2, UC_MINUS) | PAT(3, UC) |
- PAT(4, WB) | PAT(5, WT) | PAT(6, UC_MINUS) | PAT(7, UC);
- }
-
- __init_cache_modes(pat);
-}
-
-/**
- * pat_init - Initialize the PAT MSR and PAT table on the current CPU
- *
- * This function initializes PAT MSR and PAT table with an OS-defined value
- * to enable additional cache attributes, WC, WT and WP.
- *
- * This function must be called on all CPUs using the specific sequence of
- * operations defined in Intel SDM. mtrr_rendezvous_handler() provides this
- * procedure for PAT.
- */
-void pat_init(void)
-{
- u64 pat;
- struct cpuinfo_x86 *c = &boot_cpu_data;
-
-#ifndef CONFIG_X86_PAT
- pr_info_once("x86/PAT: PAT support disabled because CONFIG_X86_PAT is disabled in the kernel.\n");
-#endif
-
- if (pat_disabled)
- return;
-
- if ((c->x86_vendor == X86_VENDOR_INTEL) &&
- (((c->x86 == 0x6) && (c->x86_model <= 0xd)) ||
- ((c->x86 == 0xf) && (c->x86_model <= 0x6)))) {
- /*
- * PAT support with the lower four entries. Intel Pentium 2,
- * 3, M, and 4 are affected by PAT errata, which makes the
- * upper four entries unusable. To be on the safe side, we don't
- * use those.
- *
- * PTE encoding:
- * PAT
- * |PCD
- * ||PWT PAT
- * ||| slot
- * 000 0 WB : _PAGE_CACHE_MODE_WB
- * 001 1 WC : _PAGE_CACHE_MODE_WC
- * 010 2 UC-: _PAGE_CACHE_MODE_UC_MINUS
- * 011 3 UC : _PAGE_CACHE_MODE_UC
- * PAT bit unused
- *
- * NOTE: When WT or WP is used, it is redirected to UC- per
- * the default setup in __cachemode2pte_tbl[].
- */
- pat = PAT(0, WB) | PAT(1, WC) | PAT(2, UC_MINUS) | PAT(3, UC) |
- PAT(4, WB) | PAT(5, WC) | PAT(6, UC_MINUS) | PAT(7, UC);
- } else {
- /*
- * Full PAT support. We put WT in slot 7 to improve
- * robustness in the presence of errata that might cause
- * the high PAT bit to be ignored. This way, a buggy slot 7
- * access will hit slot 3, and slot 3 is UC, so at worst
- * we lose performance without causing a correctness issue.
- * Pentium 4 erratum N46 is an example for such an erratum,
- * although we try not to use PAT at all on affected CPUs.
- *
- * PTE encoding:
- * PAT
- * |PCD
- * ||PWT PAT
- * ||| slot
- * 000 0 WB : _PAGE_CACHE_MODE_WB
- * 001 1 WC : _PAGE_CACHE_MODE_WC
- * 010 2 UC-: _PAGE_CACHE_MODE_UC_MINUS
- * 011 3 UC : _PAGE_CACHE_MODE_UC
- * 100 4 WB : Reserved
- * 101 5 WP : _PAGE_CACHE_MODE_WP
- * 110 6 UC-: Reserved
- * 111 7 WT : _PAGE_CACHE_MODE_WT
- *
- * The reserved slots are unused, but mapped to their
- * corresponding types in the presence of PAT errata.
- */
- pat = PAT(0, WB) | PAT(1, WC) | PAT(2, UC_MINUS) | PAT(3, UC) |
- PAT(4, WB) | PAT(5, WP) | PAT(6, UC_MINUS) | PAT(7, WT);
- }
-
- if (!pat_bp_initialized) {
- pat_bp_init(pat);
- pat_bp_initialized = true;
- } else {
- pat_ap_init(pat);
- }
-}
-
-#undef PAT
-
-static DEFINE_SPINLOCK(memtype_lock); /* protects memtype accesses */
-
-/*
- * Does intersection of PAT memory type and MTRR memory type and returns
- * the resulting memory type as PAT understands it.
- * (Type in pat and mtrr will not have same value)
- * The intersection is based on "Effective Memory Type" tables in IA-32
- * SDM vol 3a
- */
-static unsigned long pat_x_mtrr_type(u64 start, u64 end,
- enum page_cache_mode req_type)
-{
- /*
- * Look for MTRR hint to get the effective type in case where PAT
- * request is for WB.
- */
- if (req_type == _PAGE_CACHE_MODE_WB) {
- u8 mtrr_type, uniform;
-
- mtrr_type = mtrr_type_lookup(start, end, &uniform);
- if (mtrr_type != MTRR_TYPE_WRBACK)
- return _PAGE_CACHE_MODE_UC_MINUS;
-
- return _PAGE_CACHE_MODE_WB;
- }
-
- return req_type;
-}
-
-struct pagerange_state {
- unsigned long cur_pfn;
- int ram;
- int not_ram;
-};
-
-static int
-pagerange_is_ram_callback(unsigned long initial_pfn, unsigned long total_nr_pages, void *arg)
-{
- struct pagerange_state *state = arg;
-
- state->not_ram |= initial_pfn > state->cur_pfn;
- state->ram |= total_nr_pages > 0;
- state->cur_pfn = initial_pfn + total_nr_pages;
-
- return state->ram && state->not_ram;
-}
-
-static int pat_pagerange_is_ram(resource_size_t start, resource_size_t end)
-{
- int ret = 0;
- unsigned long start_pfn = start >> PAGE_SHIFT;
- unsigned long end_pfn = (end + PAGE_SIZE - 1) >> PAGE_SHIFT;
- struct pagerange_state state = {start_pfn, 0, 0};
-
- /*
- * For legacy reasons, physical address range in the legacy ISA
- * region is tracked as non-RAM. This will allow users of
- * /dev/mem to map portions of legacy ISA region, even when
- * some of those portions are listed(or not even listed) with
- * different e820 types(RAM/reserved/..)
- */
- if (start_pfn < ISA_END_ADDRESS >> PAGE_SHIFT)
- start_pfn = ISA_END_ADDRESS >> PAGE_SHIFT;
-
- if (start_pfn < end_pfn) {
- ret = walk_system_ram_range(start_pfn, end_pfn - start_pfn,
- &state, pagerange_is_ram_callback);
- }
-
- return (ret > 0) ? -1 : (state.ram ? 1 : 0);
-}
-
-/*
- * For RAM pages, we use page flags to mark the pages with appropriate type.
- * The page flags are limited to four types, WB (default), WC, WT and UC-.
- * WP request fails with -EINVAL, and UC gets redirected to UC-. Setting
- * a new memory type is only allowed for a page mapped with the default WB
- * type.
- *
- * Here we do two passes:
- * - Find the memtype of all the pages in the range, look for any conflicts.
- * - In case of no conflicts, set the new memtype for pages in the range.
- */
-static int reserve_ram_pages_type(u64 start, u64 end,
- enum page_cache_mode req_type,
- enum page_cache_mode *new_type)
-{
- struct page *page;
- u64 pfn;
-
- if (req_type == _PAGE_CACHE_MODE_WP) {
- if (new_type)
- *new_type = _PAGE_CACHE_MODE_UC_MINUS;
- return -EINVAL;
- }
-
- if (req_type == _PAGE_CACHE_MODE_UC) {
- /* We do not support strong UC */
- WARN_ON_ONCE(1);
- req_type = _PAGE_CACHE_MODE_UC_MINUS;
- }
-
- for (pfn = (start >> PAGE_SHIFT); pfn < (end >> PAGE_SHIFT); ++pfn) {
- enum page_cache_mode type;
-
- page = pfn_to_page(pfn);
- type = get_page_memtype(page);
- if (type != _PAGE_CACHE_MODE_WB) {
- pr_info("x86/PAT: reserve_ram_pages_type failed [mem %#010Lx-%#010Lx], track 0x%x, req 0x%x\n",
- start, end - 1, type, req_type);
- if (new_type)
- *new_type = type;
-
- return -EBUSY;
- }
- }
-
- if (new_type)
- *new_type = req_type;
-
- for (pfn = (start >> PAGE_SHIFT); pfn < (end >> PAGE_SHIFT); ++pfn) {
- page = pfn_to_page(pfn);
- set_page_memtype(page, req_type);
- }
- return 0;
-}
-
-static int free_ram_pages_type(u64 start, u64 end)
-{
- struct page *page;
- u64 pfn;
-
- for (pfn = (start >> PAGE_SHIFT); pfn < (end >> PAGE_SHIFT); ++pfn) {
- page = pfn_to_page(pfn);
- set_page_memtype(page, _PAGE_CACHE_MODE_WB);
- }
- return 0;
-}
-
-static u64 sanitize_phys(u64 address)
-{
- /*
- * When changing the memtype for pages containing poison allow
- * for a "decoy" virtual address (bit 63 clear) passed to
- * set_memory_X(). __pa() on a "decoy" address results in a
- * physical address with bit 63 set.
- *
- * Decoy addresses are not present for 32-bit builds, see
- * set_mce_nospec().
- */
- if (IS_ENABLED(CONFIG_X86_64))
- return address & __PHYSICAL_MASK;
- return address;
-}
-
-/*
- * req_type typically has one of the:
- * - _PAGE_CACHE_MODE_WB
- * - _PAGE_CACHE_MODE_WC
- * - _PAGE_CACHE_MODE_UC_MINUS
- * - _PAGE_CACHE_MODE_UC
- * - _PAGE_CACHE_MODE_WT
- *
- * If new_type is NULL, function will return an error if it cannot reserve the
- * region with req_type. If new_type is non-NULL, function will return
- * available type in new_type in case of no error. In case of any error
- * it will return a negative return value.
- */
-int reserve_memtype(u64 start, u64 end, enum page_cache_mode req_type,
- enum page_cache_mode *new_type)
-{
- struct memtype *entry_new;
- enum page_cache_mode actual_type;
- int is_range_ram;
- int err = 0;
-
- start = sanitize_phys(start);
- end = sanitize_phys(end);
- if (start >= end) {
- WARN(1, "%s failed: [mem %#010Lx-%#010Lx], req %s\n", __func__,
- start, end - 1, cattr_name(req_type));
- return -EINVAL;
- }
-
- if (!pat_enabled()) {
- /* This is identical to page table setting without PAT */
- if (new_type)
- *new_type = req_type;
- return 0;
- }
-
- /* Low ISA region is always mapped WB in page table. No need to track */
- if (x86_platform.is_untracked_pat_range(start, end)) {
- if (new_type)
- *new_type = _PAGE_CACHE_MODE_WB;
- return 0;
- }
-
- /*
- * Call mtrr_lookup to get the type hint. This is an
- * optimization for /dev/mem mmap'ers into WB memory (BIOS
- * tools and ACPI tools). Use WB request for WB memory and use
- * UC_MINUS otherwise.
- */
- actual_type = pat_x_mtrr_type(start, end, req_type);
-
- if (new_type)
- *new_type = actual_type;
-
- is_range_ram = pat_pagerange_is_ram(start, end);
- if (is_range_ram == 1) {
-
- err = reserve_ram_pages_type(start, end, req_type, new_type);
-
- return err;
- } else if (is_range_ram < 0) {
- return -EINVAL;
- }
-
- entry_new = kzalloc(sizeof(struct memtype), GFP_KERNEL);
- if (!entry_new)
- return -ENOMEM;
-
- entry_new->start = start;
- entry_new->end = end;
- entry_new->type = actual_type;
-
- spin_lock(&memtype_lock);
-
- err = memtype_check_insert(entry_new, new_type);
- if (err) {
- pr_info("x86/PAT: reserve_memtype failed [mem %#010Lx-%#010Lx], track %s, req %s\n",
- start, end - 1,
- cattr_name(entry_new->type), cattr_name(req_type));
- kfree(entry_new);
- spin_unlock(&memtype_lock);
-
- return err;
- }
-
- spin_unlock(&memtype_lock);
-
- dprintk("reserve_memtype added [mem %#010Lx-%#010Lx], track %s, req %s, ret %s\n",
- start, end - 1, cattr_name(entry_new->type), cattr_name(req_type),
- new_type ? cattr_name(*new_type) : "-");
-
- return err;
-}
-
-int free_memtype(u64 start, u64 end)
-{
- int is_range_ram;
- struct memtype *entry_old;
-
- if (!pat_enabled())
- return 0;
-
- start = sanitize_phys(start);
- end = sanitize_phys(end);
-
- /* Low ISA region is always mapped WB. No need to track */
- if (x86_platform.is_untracked_pat_range(start, end))
- return 0;
-
- is_range_ram = pat_pagerange_is_ram(start, end);
- if (is_range_ram == 1)
- return free_ram_pages_type(start, end);
- if (is_range_ram < 0)
- return -EINVAL;
-
- spin_lock(&memtype_lock);
- entry_old = memtype_erase(start, end);
- spin_unlock(&memtype_lock);
-
- if (IS_ERR(entry_old)) {
- pr_info("x86/PAT: %s:%d freeing invalid memtype [mem %#010Lx-%#010Lx]\n",
- current->comm, current->pid, start, end - 1);
- return -EINVAL;
- }
-
- kfree(entry_old);
-
- dprintk("free_memtype request [mem %#010Lx-%#010Lx]\n", start, end - 1);
-
- return 0;
-}
-
-
-/**
- * lookup_memtype - Looksup the memory type for a physical address
- * @paddr: physical address of which memory type needs to be looked up
- *
- * Only to be called when PAT is enabled
- *
- * Returns _PAGE_CACHE_MODE_WB, _PAGE_CACHE_MODE_WC, _PAGE_CACHE_MODE_UC_MINUS
- * or _PAGE_CACHE_MODE_WT.
- */
-static enum page_cache_mode lookup_memtype(u64 paddr)
-{
- enum page_cache_mode rettype = _PAGE_CACHE_MODE_WB;
- struct memtype *entry;
-
- if (x86_platform.is_untracked_pat_range(paddr, paddr + PAGE_SIZE))
- return rettype;
-
- if (pat_pagerange_is_ram(paddr, paddr + PAGE_SIZE)) {
- struct page *page;
-
- page = pfn_to_page(paddr >> PAGE_SHIFT);
- return get_page_memtype(page);
- }
-
- spin_lock(&memtype_lock);
-
- entry = memtype_lookup(paddr);
- if (entry != NULL)
- rettype = entry->type;
- else
- rettype = _PAGE_CACHE_MODE_UC_MINUS;
-
- spin_unlock(&memtype_lock);
-
- return rettype;
-}
-
-/**
- * pat_pfn_immune_to_uc_mtrr - Check whether the PAT memory type
- * of @pfn cannot be overridden by UC MTRR memory type.
- *
- * Only to be called when PAT is enabled.
- *
- * Returns true, if the PAT memory type of @pfn is UC, UC-, or WC.
- * Returns false in other cases.
- */
-bool pat_pfn_immune_to_uc_mtrr(unsigned long pfn)
-{
- enum page_cache_mode cm = lookup_memtype(PFN_PHYS(pfn));
-
- return cm == _PAGE_CACHE_MODE_UC ||
- cm == _PAGE_CACHE_MODE_UC_MINUS ||
- cm == _PAGE_CACHE_MODE_WC;
-}
-EXPORT_SYMBOL_GPL(pat_pfn_immune_to_uc_mtrr);
-
-/**
- * io_reserve_memtype - Request a memory type mapping for a region of memory
- * @start: start (physical address) of the region
- * @end: end (physical address) of the region
- * @type: A pointer to memtype, with requested type. On success, requested
- * or any other compatible type that was available for the region is returned
- *
- * On success, returns 0
- * On failure, returns non-zero
- */
-int io_reserve_memtype(resource_size_t start, resource_size_t end,
- enum page_cache_mode *type)
-{
- resource_size_t size = end - start;
- enum page_cache_mode req_type = *type;
- enum page_cache_mode new_type;
- int ret;
-
- WARN_ON_ONCE(iomem_map_sanity_check(start, size));
-
- ret = reserve_memtype(start, end, req_type, &new_type);
- if (ret)
- goto out_err;
-
- if (!is_new_memtype_allowed(start, size, req_type, new_type))
- goto out_free;
-
- if (kernel_map_sync_memtype(start, size, new_type) < 0)
- goto out_free;
-
- *type = new_type;
- return 0;
-
-out_free:
- free_memtype(start, end);
- ret = -EBUSY;
-out_err:
- return ret;
-}
-
-/**
- * io_free_memtype - Release a memory type mapping for a region of memory
- * @start: start (physical address) of the region
- * @end: end (physical address) of the region
- */
-void io_free_memtype(resource_size_t start, resource_size_t end)
-{
- free_memtype(start, end);
-}
-
-int arch_io_reserve_memtype_wc(resource_size_t start, resource_size_t size)
-{
- enum page_cache_mode type = _PAGE_CACHE_MODE_WC;
-
- return io_reserve_memtype(start, start + size, &type);
-}
-EXPORT_SYMBOL(arch_io_reserve_memtype_wc);
-
-void arch_io_free_memtype_wc(resource_size_t start, resource_size_t size)
-{
- io_free_memtype(start, start + size);
-}
-EXPORT_SYMBOL(arch_io_free_memtype_wc);
-
-pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn,
- unsigned long size, pgprot_t vma_prot)
-{
- if (!phys_mem_access_encrypted(pfn << PAGE_SHIFT, size))
- vma_prot = pgprot_decrypted(vma_prot);
-
- return vma_prot;
-}
-
-#ifdef CONFIG_STRICT_DEVMEM
-/* This check is done in drivers/char/mem.c in case of STRICT_DEVMEM */
-static inline int range_is_allowed(unsigned long pfn, unsigned long size)
-{
- return 1;
-}
-#else
-/* This check is needed to avoid cache aliasing when PAT is enabled */
-static inline int range_is_allowed(unsigned long pfn, unsigned long size)
-{
- u64 from = ((u64)pfn) << PAGE_SHIFT;
- u64 to = from + size;
- u64 cursor = from;
-
- if (!pat_enabled())
- return 1;
-
- while (cursor < to) {
- if (!devmem_is_allowed(pfn))
- return 0;
- cursor += PAGE_SIZE;
- pfn++;
- }
- return 1;
-}
-#endif /* CONFIG_STRICT_DEVMEM */
-
-int phys_mem_access_prot_allowed(struct file *file, unsigned long pfn,
- unsigned long size, pgprot_t *vma_prot)
-{
- enum page_cache_mode pcm = _PAGE_CACHE_MODE_WB;
-
- if (!range_is_allowed(pfn, size))
- return 0;
-
- if (file->f_flags & O_DSYNC)
- pcm = _PAGE_CACHE_MODE_UC_MINUS;
-
- *vma_prot = __pgprot((pgprot_val(*vma_prot) & ~_PAGE_CACHE_MASK) |
- cachemode2protval(pcm));
- return 1;
-}
-
-/*
- * Change the memory type for the physical address range in kernel identity
- * mapping space if that range is a part of identity map.
- */
-int kernel_map_sync_memtype(u64 base, unsigned long size,
- enum page_cache_mode pcm)
-{
- unsigned long id_sz;
-
- if (base > __pa(high_memory-1))
- return 0;
-
- /*
- * Some areas in the middle of the kernel identity range
- * are not mapped, for example the PCI space.
- */
- if (!page_is_ram(base >> PAGE_SHIFT))
- return 0;
-
- id_sz = (__pa(high_memory-1) <= base + size) ?
- __pa(high_memory) - base : size;
-
- if (ioremap_change_attr((unsigned long)__va(base), id_sz, pcm) < 0) {
- pr_info("x86/PAT: %s:%d ioremap_change_attr failed %s for [mem %#010Lx-%#010Lx]\n",
- current->comm, current->pid,
- cattr_name(pcm),
- base, (unsigned long long)(base + size-1));
- return -EINVAL;
- }
- return 0;
-}
-
-/*
- * Internal interface to reserve a range of physical memory with prot.
- * Reserved non RAM regions only and after successful reserve_memtype,
- * this func also keeps identity mapping (if any) in sync with this new prot.
- */
-static int reserve_pfn_range(u64 paddr, unsigned long size, pgprot_t *vma_prot,
- int strict_prot)
-{
- int is_ram = 0;
- int ret;
- enum page_cache_mode want_pcm = pgprot2cachemode(*vma_prot);
- enum page_cache_mode pcm = want_pcm;
-
- is_ram = pat_pagerange_is_ram(paddr, paddr + size);
-
- /*
- * reserve_pfn_range() for RAM pages. We do not refcount to keep
- * track of number of mappings of RAM pages. We can assert that
- * the type requested matches the type of first page in the range.
- */
- if (is_ram) {
- if (!pat_enabled())
- return 0;
-
- pcm = lookup_memtype(paddr);
- if (want_pcm != pcm) {
- pr_warn("x86/PAT: %s:%d map pfn RAM range req %s for [mem %#010Lx-%#010Lx], got %s\n",
- current->comm, current->pid,
- cattr_name(want_pcm),
- (unsigned long long)paddr,
- (unsigned long long)(paddr + size - 1),
- cattr_name(pcm));
- *vma_prot = __pgprot((pgprot_val(*vma_prot) &
- (~_PAGE_CACHE_MASK)) |
- cachemode2protval(pcm));
- }
- return 0;
- }
-
- ret = reserve_memtype(paddr, paddr + size, want_pcm, &pcm);
- if (ret)
- return ret;
-
- if (pcm != want_pcm) {
- if (strict_prot ||
- !is_new_memtype_allowed(paddr, size, want_pcm, pcm)) {
- free_memtype(paddr, paddr + size);
- pr_err("x86/PAT: %s:%d map pfn expected mapping type %s for [mem %#010Lx-%#010Lx], got %s\n",
- current->comm, current->pid,
- cattr_name(want_pcm),
- (unsigned long long)paddr,
- (unsigned long long)(paddr + size - 1),
- cattr_name(pcm));
- return -EINVAL;
- }
- /*
- * We allow returning different type than the one requested in
- * non strict case.
- */
- *vma_prot = __pgprot((pgprot_val(*vma_prot) &
- (~_PAGE_CACHE_MASK)) |
- cachemode2protval(pcm));
- }
-
- if (kernel_map_sync_memtype(paddr, size, pcm) < 0) {
- free_memtype(paddr, paddr + size);
- return -EINVAL;
- }
- return 0;
-}
-
-/*
- * Internal interface to free a range of physical memory.
- * Frees non RAM regions only.
- */
-static void free_pfn_range(u64 paddr, unsigned long size)
-{
- int is_ram;
-
- is_ram = pat_pagerange_is_ram(paddr, paddr + size);
- if (is_ram == 0)
- free_memtype(paddr, paddr + size);
-}
-
-/*
- * track_pfn_copy is called when vma that is covering the pfnmap gets
- * copied through copy_page_range().
- *
- * If the vma has a linear pfn mapping for the entire range, we get the prot
- * from pte and reserve the entire vma range with single reserve_pfn_range call.
- */
-int track_pfn_copy(struct vm_area_struct *vma)
-{
- resource_size_t paddr;
- unsigned long prot;
- unsigned long vma_size = vma->vm_end - vma->vm_start;
- pgprot_t pgprot;
-
- if (vma->vm_flags & VM_PAT) {
- /*
- * reserve the whole chunk covered by vma. We need the
- * starting address and protection from pte.
- */
- if (follow_phys(vma, vma->vm_start, 0, &prot, &paddr)) {
- WARN_ON_ONCE(1);
- return -EINVAL;
- }
- pgprot = __pgprot(prot);
- return reserve_pfn_range(paddr, vma_size, &pgprot, 1);
- }
-
- return 0;
-}
-
-/*
- * prot is passed in as a parameter for the new mapping. If the vma has
- * a linear pfn mapping for the entire range, or no vma is provided,
- * reserve the entire pfn + size range with single reserve_pfn_range
- * call.
- */
-int track_pfn_remap(struct vm_area_struct *vma, pgprot_t *prot,
- unsigned long pfn, unsigned long addr, unsigned long size)
-{
- resource_size_t paddr = (resource_size_t)pfn << PAGE_SHIFT;
- enum page_cache_mode pcm;
-
- /* reserve the whole chunk starting from paddr */
- if (!vma || (addr == vma->vm_start
- && size == (vma->vm_end - vma->vm_start))) {
- int ret;
-
- ret = reserve_pfn_range(paddr, size, prot, 0);
- if (ret == 0 && vma)
- vma->vm_flags |= VM_PAT;
- return ret;
- }
-
- if (!pat_enabled())
- return 0;
-
- /*
- * For anything smaller than the vma size we set prot based on the
- * lookup.
- */
- pcm = lookup_memtype(paddr);
-
- /* Check memtype for the remaining pages */
- while (size > PAGE_SIZE) {
- size -= PAGE_SIZE;
- paddr += PAGE_SIZE;
- if (pcm != lookup_memtype(paddr))
- return -EINVAL;
- }
-
- *prot = __pgprot((pgprot_val(*prot) & (~_PAGE_CACHE_MASK)) |
- cachemode2protval(pcm));
-
- return 0;
-}
-
-void track_pfn_insert(struct vm_area_struct *vma, pgprot_t *prot, pfn_t pfn)
-{
- enum page_cache_mode pcm;
-
- if (!pat_enabled())
- return;
-
- /* Set prot based on lookup */
- pcm = lookup_memtype(pfn_t_to_phys(pfn));
- *prot = __pgprot((pgprot_val(*prot) & (~_PAGE_CACHE_MASK)) |
- cachemode2protval(pcm));
-}
-
-/*
- * untrack_pfn is called while unmapping a pfnmap for a region.
- * untrack can be called for a specific region indicated by pfn and size or
- * can be for the entire vma (in which case pfn, size are zero).
- */
-void untrack_pfn(struct vm_area_struct *vma, unsigned long pfn,
- unsigned long size)
-{
- resource_size_t paddr;
- unsigned long prot;
-
- if (vma && !(vma->vm_flags & VM_PAT))
- return;
-
- /* free the chunk starting from pfn or the whole chunk */
- paddr = (resource_size_t)pfn << PAGE_SHIFT;
- if (!paddr && !size) {
- if (follow_phys(vma, vma->vm_start, 0, &prot, &paddr)) {
- WARN_ON_ONCE(1);
- return;
- }
-
- size = vma->vm_end - vma->vm_start;
- }
- free_pfn_range(paddr, size);
- if (vma)
- vma->vm_flags &= ~VM_PAT;
-}
-
-/*
- * untrack_pfn_moved is called, while mremapping a pfnmap for a new region,
- * with the old vma after its pfnmap page table has been removed. The new
- * vma has a new pfnmap to the same pfn & cache type with VM_PAT set.
- */
-void untrack_pfn_moved(struct vm_area_struct *vma)
-{
- vma->vm_flags &= ~VM_PAT;
-}
-
-pgprot_t pgprot_writecombine(pgprot_t prot)
-{
- return __pgprot(pgprot_val(prot) |
- cachemode2protval(_PAGE_CACHE_MODE_WC));
-}
-EXPORT_SYMBOL_GPL(pgprot_writecombine);
-
-pgprot_t pgprot_writethrough(pgprot_t prot)
-{
- return __pgprot(pgprot_val(prot) |
- cachemode2protval(_PAGE_CACHE_MODE_WT));
-}
-EXPORT_SYMBOL_GPL(pgprot_writethrough);
-
-#if defined(CONFIG_DEBUG_FS) && defined(CONFIG_X86_PAT)
-
-/*
- * We are allocating a temporary printout-entry to be passed
- * between seq_start()/next() and seq_show():
- */
-static struct memtype *memtype_get_idx(loff_t pos)
-{
- struct memtype *entry_print;
- int ret;
-
- entry_print = kzalloc(sizeof(struct memtype), GFP_KERNEL);
- if (!entry_print)
- return NULL;
-
- spin_lock(&memtype_lock);
- ret = memtype_copy_nth_element(entry_print, pos);
- spin_unlock(&memtype_lock);
-
- /* Free it on error: */
- if (ret) {
- kfree(entry_print);
- return NULL;
- }
-
- return entry_print;
-}
-
-static void *memtype_seq_start(struct seq_file *seq, loff_t *pos)
-{
- if (*pos == 0) {
- ++*pos;
- seq_puts(seq, "PAT memtype list:\n");
- }
-
- return memtype_get_idx(*pos);
-}
-
-static void *memtype_seq_next(struct seq_file *seq, void *v, loff_t *pos)
-{
- ++*pos;
- return memtype_get_idx(*pos);
-}
-
-static void memtype_seq_stop(struct seq_file *seq, void *v)
-{
-}
-
-static int memtype_seq_show(struct seq_file *seq, void *v)
-{
- struct memtype *entry_print = (struct memtype *)v;
-
- seq_printf(seq, "PAT: [mem 0x%016Lx-0x%016Lx] %s\n",
- entry_print->start,
- entry_print->end,
- cattr_name(entry_print->type));
-
- kfree(entry_print);
-
- return 0;
-}
-
-static const struct seq_operations memtype_seq_ops = {
- .start = memtype_seq_start,
- .next = memtype_seq_next,
- .stop = memtype_seq_stop,
- .show = memtype_seq_show,
-};
-
-static int memtype_seq_open(struct inode *inode, struct file *file)
-{
- return seq_open(file, &memtype_seq_ops);
-}
-
-static const struct file_operations memtype_fops = {
- .open = memtype_seq_open,
- .read = seq_read,
- .llseek = seq_lseek,
- .release = seq_release,
-};
-
-static int __init pat_memtype_list_init(void)
-{
- if (pat_enabled()) {
- debugfs_create_file("pat_memtype_list", S_IRUSR,
- arch_debugfs_dir, NULL, &memtype_fops);
- }
- return 0;
-}
-late_initcall(pat_memtype_list_init);
-
-#endif /* CONFIG_DEBUG_FS && CONFIG_X86_PAT */
diff --git a/arch/x86/mm/pat/Makefile b/arch/x86/mm/pat/Makefile
new file mode 100644
index 0000000..ea464c9
--- /dev/null
+++ b/arch/x86/mm/pat/Makefile
@@ -0,0 +1,5 @@
+# SPDX-License-Identifier: GPL-2.0
+
+obj-y := set_memory.o memtype.o
+
+obj-$(CONFIG_X86_PAT) += memtype_interval.o
diff --git a/arch/x86/mm/pat/cpa-test.c b/arch/x86/mm/pat/cpa-test.c
new file mode 100644
index 0000000..facce27
--- /dev/null
+++ b/arch/x86/mm/pat/cpa-test.c
@@ -0,0 +1,278 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * self test for change_page_attr.
+ *
+ * Clears the a test pte bit on random pages in the direct mapping,
+ * then reverts and compares page tables forwards and afterwards.
+ */
+#include <linux/memblock.h>
+#include <linux/kthread.h>
+#include <linux/random.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/mm.h>
+#include <linux/vmalloc.h>
+
+#include <asm/cacheflush.h>
+#include <asm/pgtable.h>
+#include <asm/kdebug.h>
+
+/*
+ * Only print the results of the first pass:
+ */
+static __read_mostly int print = 1;
+
+enum {
+ NTEST = 3 * 100,
+ NPAGES = 100,
+#ifdef CONFIG_X86_64
+ LPS = (1 << PMD_SHIFT),
+#elif defined(CONFIG_X86_PAE)
+ LPS = (1 << PMD_SHIFT),
+#else
+ LPS = (1 << 22),
+#endif
+ GPS = (1<<30)
+};
+
+#define PAGE_CPA_TEST __pgprot(_PAGE_CPA_TEST)
+
+static int pte_testbit(pte_t pte)
+{
+ return pte_flags(pte) & _PAGE_SOFTW1;
+}
+
+struct split_state {
+ long lpg, gpg, spg, exec;
+ long min_exec, max_exec;
+};
+
+static int print_split(struct split_state *s)
+{
+ long i, expected, missed = 0;
+ int err = 0;
+
+ s->lpg = s->gpg = s->spg = s->exec = 0;
+ s->min_exec = ~0UL;
+ s->max_exec = 0;
+ for (i = 0; i < max_pfn_mapped; ) {
+ unsigned long addr = (unsigned long)__va(i << PAGE_SHIFT);
+ unsigned int level;
+ pte_t *pte;
+
+ pte = lookup_address(addr, &level);
+ if (!pte) {
+ missed++;
+ i++;
+ continue;
+ }
+
+ if (level == PG_LEVEL_1G && sizeof(long) == 8) {
+ s->gpg++;
+ i += GPS/PAGE_SIZE;
+ } else if (level == PG_LEVEL_2M) {
+ if ((pte_val(*pte) & _PAGE_PRESENT) && !(pte_val(*pte) & _PAGE_PSE)) {
+ printk(KERN_ERR
+ "%lx level %d but not PSE %Lx\n",
+ addr, level, (u64)pte_val(*pte));
+ err = 1;
+ }
+ s->lpg++;
+ i += LPS/PAGE_SIZE;
+ } else {
+ s->spg++;
+ i++;
+ }
+ if (!(pte_val(*pte) & _PAGE_NX)) {
+ s->exec++;
+ if (addr < s->min_exec)
+ s->min_exec = addr;
+ if (addr > s->max_exec)
+ s->max_exec = addr;
+ }
+ }
+ if (print) {
+ printk(KERN_INFO
+ " 4k %lu large %lu gb %lu x %lu[%lx-%lx] miss %lu\n",
+ s->spg, s->lpg, s->gpg, s->exec,
+ s->min_exec != ~0UL ? s->min_exec : 0,
+ s->max_exec, missed);
+ }
+
+ expected = (s->gpg*GPS + s->lpg*LPS)/PAGE_SIZE + s->spg + missed;
+ if (expected != i) {
+ printk(KERN_ERR "CPA max_pfn_mapped %lu but expected %lu\n",
+ max_pfn_mapped, expected);
+ return 1;
+ }
+ return err;
+}
+
+static unsigned long addr[NTEST];
+static unsigned int len[NTEST];
+
+static struct page *pages[NPAGES];
+static unsigned long addrs[NPAGES];
+
+/* Change the global bit on random pages in the direct mapping */
+static int pageattr_test(void)
+{
+ struct split_state sa, sb, sc;
+ unsigned long *bm;
+ pte_t *pte, pte0;
+ int failed = 0;
+ unsigned int level;
+ int i, k;
+ int err;
+
+ if (print)
+ printk(KERN_INFO "CPA self-test:\n");
+
+ bm = vzalloc((max_pfn_mapped + 7) / 8);
+ if (!bm) {
+ printk(KERN_ERR "CPA Cannot vmalloc bitmap\n");
+ return -ENOMEM;
+ }
+
+ failed += print_split(&sa);
+
+ for (i = 0; i < NTEST; i++) {
+ unsigned long pfn = prandom_u32() % max_pfn_mapped;
+
+ addr[i] = (unsigned long)__va(pfn << PAGE_SHIFT);
+ len[i] = prandom_u32() % NPAGES;
+ len[i] = min_t(unsigned long, len[i], max_pfn_mapped - pfn - 1);
+
+ if (len[i] == 0)
+ len[i] = 1;
+
+ pte = NULL;
+ pte0 = pfn_pte(0, __pgprot(0)); /* shut gcc up */
+
+ for (k = 0; k < len[i]; k++) {
+ pte = lookup_address(addr[i] + k*PAGE_SIZE, &level);
+ if (!pte || pgprot_val(pte_pgprot(*pte)) == 0 ||
+ !(pte_val(*pte) & _PAGE_PRESENT)) {
+ addr[i] = 0;
+ break;
+ }
+ if (k == 0) {
+ pte0 = *pte;
+ } else {
+ if (pgprot_val(pte_pgprot(*pte)) !=
+ pgprot_val(pte_pgprot(pte0))) {
+ len[i] = k;
+ break;
+ }
+ }
+ if (test_bit(pfn + k, bm)) {
+ len[i] = k;
+ break;
+ }
+ __set_bit(pfn + k, bm);
+ addrs[k] = addr[i] + k*PAGE_SIZE;
+ pages[k] = pfn_to_page(pfn + k);
+ }
+ if (!addr[i] || !pte || !k) {
+ addr[i] = 0;
+ continue;
+ }
+
+ switch (i % 3) {
+ case 0:
+ err = change_page_attr_set(&addr[i], len[i], PAGE_CPA_TEST, 0);
+ break;
+
+ case 1:
+ err = change_page_attr_set(addrs, len[1], PAGE_CPA_TEST, 1);
+ break;
+
+ case 2:
+ err = cpa_set_pages_array(pages, len[i], PAGE_CPA_TEST);
+ break;
+ }
+
+
+ if (err < 0) {
+ printk(KERN_ERR "CPA %d failed %d\n", i, err);
+ failed++;
+ }
+
+ pte = lookup_address(addr[i], &level);
+ if (!pte || !pte_testbit(*pte) || pte_huge(*pte)) {
+ printk(KERN_ERR "CPA %lx: bad pte %Lx\n", addr[i],
+ pte ? (u64)pte_val(*pte) : 0ULL);
+ failed++;
+ }
+ if (level != PG_LEVEL_4K) {
+ printk(KERN_ERR "CPA %lx: unexpected level %d\n",
+ addr[i], level);
+ failed++;
+ }
+
+ }
+ vfree(bm);
+
+ failed += print_split(&sb);
+
+ for (i = 0; i < NTEST; i++) {
+ if (!addr[i])
+ continue;
+ pte = lookup_address(addr[i], &level);
+ if (!pte) {
+ printk(KERN_ERR "CPA lookup of %lx failed\n", addr[i]);
+ failed++;
+ continue;
+ }
+ err = change_page_attr_clear(&addr[i], len[i], PAGE_CPA_TEST, 0);
+ if (err < 0) {
+ printk(KERN_ERR "CPA reverting failed: %d\n", err);
+ failed++;
+ }
+ pte = lookup_address(addr[i], &level);
+ if (!pte || pte_testbit(*pte)) {
+ printk(KERN_ERR "CPA %lx: bad pte after revert %Lx\n",
+ addr[i], pte ? (u64)pte_val(*pte) : 0ULL);
+ failed++;
+ }
+
+ }
+
+ failed += print_split(&sc);
+
+ if (failed) {
+ WARN(1, KERN_ERR "NOT PASSED. Please report.\n");
+ return -EINVAL;
+ } else {
+ if (print)
+ printk(KERN_INFO "ok.\n");
+ }
+
+ return 0;
+}
+
+static int do_pageattr_test(void *__unused)
+{
+ while (!kthread_should_stop()) {
+ schedule_timeout_interruptible(HZ*30);
+ if (pageattr_test() < 0)
+ break;
+ if (print)
+ print--;
+ }
+ return 0;
+}
+
+static int start_pageattr_test(void)
+{
+ struct task_struct *p;
+
+ p = kthread_create(do_pageattr_test, NULL, "pageattr-test");
+ if (!IS_ERR(p))
+ wake_up_process(p);
+ else
+ WARN_ON(1);
+
+ return 0;
+}
+device_initcall(start_pageattr_test);
diff --git a/arch/x86/mm/pat/memtype.c b/arch/x86/mm/pat/memtype.c
new file mode 100644
index 0000000..76532f0
--- /dev/null
+++ b/arch/x86/mm/pat/memtype.c
@@ -0,0 +1,1219 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Page Attribute Table (PAT) support: handle memory caching attributes in page tables.
+ *
+ * Authors: Venkatesh Pallipadi <venkatesh.pallipadi@...el.com>
+ * Suresh B Siddha <suresh.b.siddha@...el.com>
+ *
+ * Loosely based on earlier PAT patchset from Eric Biederman and Andi Kleen.
+ *
+ * Basic principles:
+ *
+ * PAT is a CPU feature supported by all modern x86 CPUs, to allow the firmware and
+ * the kernel to set one of a handful of 'caching type' attributes for physical
+ * memory ranges: uncached, write-combining, write-through, write-protected,
+ * and the most commonly used and default attribute: write-back caching.
+ *
+ * PAT support supercedes and augments MTRR support in a compatible fashion: MTRR is
+ * a hardware interface to enumerate a limited number of physical memory ranges
+ * and set their caching attributes explicitly, programmed into the CPU via MSRs.
+ * Even modern CPUs have MTRRs enabled - but these are typically not touched
+ * by the kernel or by user-space (such as the X server), we rely on PAT for any
+ * additional cache attribute logic.
+ *
+ * PAT doesn't work via explicit memory ranges, but uses page table entries to add
+ * cache attribute information to the mapped memory range: there's 3 bits used,
+ * (_PAGE_PWT, _PAGE_PCD, _PAGE_PAT), with the 8 possible values mapped by the
+ * CPU to actual cache attributes via an MSR loaded into the CPU (MSR_IA32_CR_PAT).
+ *
+ * ( There's a metric ton of finer details, such as compatibility with CPU quirks
+ * that only support 4 types of PAT entries, and interaction with MTRRs, see
+ * below for details. )
+ */
+
+#include <linux/seq_file.h>
+#include <linux/memblock.h>
+#include <linux/debugfs.h>
+#include <linux/ioport.h>
+#include <linux/kernel.h>
+#include <linux/pfn_t.h>
+#include <linux/slab.h>
+#include <linux/mm.h>
+#include <linux/fs.h>
+#include <linux/rbtree.h>
+
+#include <asm/cacheflush.h>
+#include <asm/processor.h>
+#include <asm/tlbflush.h>
+#include <asm/x86_init.h>
+#include <asm/pgtable.h>
+#include <asm/fcntl.h>
+#include <asm/e820/api.h>
+#include <asm/mtrr.h>
+#include <asm/page.h>
+#include <asm/msr.h>
+#include <asm/pat.h>
+#include <asm/io.h>
+
+#include "memtype.h"
+#include "../mm_internal.h"
+
+#undef pr_fmt
+#define pr_fmt(fmt) "" fmt
+
+static bool __read_mostly pat_bp_initialized;
+static bool __read_mostly pat_disabled = !IS_ENABLED(CONFIG_X86_PAT);
+static bool __read_mostly pat_bp_enabled;
+static bool __read_mostly pat_cm_initialized;
+
+/*
+ * PAT support is enabled by default, but can be disabled for
+ * various user-requested or hardware-forced reasons:
+ */
+void pat_disable(const char *msg_reason)
+{
+ if (pat_disabled)
+ return;
+
+ if (pat_bp_initialized) {
+ WARN_ONCE(1, "x86/PAT: PAT cannot be disabled after initialization\n");
+ return;
+ }
+
+ pat_disabled = true;
+ pr_info("x86/PAT: %s\n", msg_reason);
+}
+
+static int __init nopat(char *str)
+{
+ pat_disable("PAT support disabled via boot option.");
+ return 0;
+}
+early_param("nopat", nopat);
+
+bool pat_enabled(void)
+{
+ return pat_bp_enabled;
+}
+EXPORT_SYMBOL_GPL(pat_enabled);
+
+int pat_debug_enable;
+
+static int __init pat_debug_setup(char *str)
+{
+ pat_debug_enable = 1;
+ return 0;
+}
+__setup("debugpat", pat_debug_setup);
+
+#ifdef CONFIG_X86_PAT
+/*
+ * X86 PAT uses page flags arch_1 and uncached together to keep track of
+ * memory type of pages that have backing page struct.
+ *
+ * X86 PAT supports 4 different memory types:
+ * - _PAGE_CACHE_MODE_WB
+ * - _PAGE_CACHE_MODE_WC
+ * - _PAGE_CACHE_MODE_UC_MINUS
+ * - _PAGE_CACHE_MODE_WT
+ *
+ * _PAGE_CACHE_MODE_WB is the default type.
+ */
+
+#define _PGMT_WB 0
+#define _PGMT_WC (1UL << PG_arch_1)
+#define _PGMT_UC_MINUS (1UL << PG_uncached)
+#define _PGMT_WT (1UL << PG_uncached | 1UL << PG_arch_1)
+#define _PGMT_MASK (1UL << PG_uncached | 1UL << PG_arch_1)
+#define _PGMT_CLEAR_MASK (~_PGMT_MASK)
+
+static inline enum page_cache_mode get_page_memtype(struct page *pg)
+{
+ unsigned long pg_flags = pg->flags & _PGMT_MASK;
+
+ if (pg_flags == _PGMT_WB)
+ return _PAGE_CACHE_MODE_WB;
+ else if (pg_flags == _PGMT_WC)
+ return _PAGE_CACHE_MODE_WC;
+ else if (pg_flags == _PGMT_UC_MINUS)
+ return _PAGE_CACHE_MODE_UC_MINUS;
+ else
+ return _PAGE_CACHE_MODE_WT;
+}
+
+static inline void set_page_memtype(struct page *pg,
+ enum page_cache_mode memtype)
+{
+ unsigned long memtype_flags;
+ unsigned long old_flags;
+ unsigned long new_flags;
+
+ switch (memtype) {
+ case _PAGE_CACHE_MODE_WC:
+ memtype_flags = _PGMT_WC;
+ break;
+ case _PAGE_CACHE_MODE_UC_MINUS:
+ memtype_flags = _PGMT_UC_MINUS;
+ break;
+ case _PAGE_CACHE_MODE_WT:
+ memtype_flags = _PGMT_WT;
+ break;
+ case _PAGE_CACHE_MODE_WB:
+ default:
+ memtype_flags = _PGMT_WB;
+ break;
+ }
+
+ do {
+ old_flags = pg->flags;
+ new_flags = (old_flags & _PGMT_CLEAR_MASK) | memtype_flags;
+ } while (cmpxchg(&pg->flags, old_flags, new_flags) != old_flags);
+}
+#else
+static inline enum page_cache_mode get_page_memtype(struct page *pg)
+{
+ return -1;
+}
+static inline void set_page_memtype(struct page *pg,
+ enum page_cache_mode memtype)
+{
+}
+#endif
+
+enum {
+ PAT_UC = 0, /* uncached */
+ PAT_WC = 1, /* Write combining */
+ PAT_WT = 4, /* Write Through */
+ PAT_WP = 5, /* Write Protected */
+ PAT_WB = 6, /* Write Back (default) */
+ PAT_UC_MINUS = 7, /* UC, but can be overridden by MTRR */
+};
+
+#define CM(c) (_PAGE_CACHE_MODE_ ## c)
+
+static enum page_cache_mode pat_get_cache_mode(unsigned pat_val, char *msg)
+{
+ enum page_cache_mode cache;
+ char *cache_mode;
+
+ switch (pat_val) {
+ case PAT_UC: cache = CM(UC); cache_mode = "UC "; break;
+ case PAT_WC: cache = CM(WC); cache_mode = "WC "; break;
+ case PAT_WT: cache = CM(WT); cache_mode = "WT "; break;
+ case PAT_WP: cache = CM(WP); cache_mode = "WP "; break;
+ case PAT_WB: cache = CM(WB); cache_mode = "WB "; break;
+ case PAT_UC_MINUS: cache = CM(UC_MINUS); cache_mode = "UC- "; break;
+ default: cache = CM(WB); cache_mode = "WB "; break;
+ }
+
+ memcpy(msg, cache_mode, 4);
+
+ return cache;
+}
+
+#undef CM
+
+/*
+ * Update the cache mode to pgprot translation tables according to PAT
+ * configuration.
+ * Using lower indices is preferred, so we start with highest index.
+ */
+static void __init_cache_modes(u64 pat)
+{
+ enum page_cache_mode cache;
+ char pat_msg[33];
+ int i;
+
+ WARN_ON_ONCE(pat_cm_initialized);
+
+ pat_msg[32] = 0;
+ for (i = 7; i >= 0; i--) {
+ cache = pat_get_cache_mode((pat >> (i * 8)) & 7,
+ pat_msg + 4 * i);
+ update_cache_mode_entry(i, cache);
+ }
+ pr_info("x86/PAT: Configuration [0-7]: %s\n", pat_msg);
+
+ pat_cm_initialized = true;
+}
+
+#define PAT(x, y) ((u64)PAT_ ## y << ((x)*8))
+
+static void pat_bp_init(u64 pat)
+{
+ u64 tmp_pat;
+
+ if (!boot_cpu_has(X86_FEATURE_PAT)) {
+ pat_disable("PAT not supported by the CPU.");
+ return;
+ }
+
+ rdmsrl(MSR_IA32_CR_PAT, tmp_pat);
+ if (!tmp_pat) {
+ pat_disable("PAT support disabled by the firmware.");
+ return;
+ }
+
+ wrmsrl(MSR_IA32_CR_PAT, pat);
+ pat_bp_enabled = true;
+
+ __init_cache_modes(pat);
+}
+
+static void pat_ap_init(u64 pat)
+{
+ if (!boot_cpu_has(X86_FEATURE_PAT)) {
+ /*
+ * If this happens we are on a secondary CPU, but switched to
+ * PAT on the boot CPU. We have no way to undo PAT.
+ */
+ panic("x86/PAT: PAT enabled, but not supported by secondary CPU\n");
+ }
+
+ wrmsrl(MSR_IA32_CR_PAT, pat);
+}
+
+void init_cache_modes(void)
+{
+ u64 pat = 0;
+
+ if (pat_cm_initialized)
+ return;
+
+ if (boot_cpu_has(X86_FEATURE_PAT)) {
+ /*
+ * CPU supports PAT. Set PAT table to be consistent with
+ * PAT MSR. This case supports "nopat" boot option, and
+ * virtual machine environments which support PAT without
+ * MTRRs. In specific, Xen has unique setup to PAT MSR.
+ *
+ * If PAT MSR returns 0, it is considered invalid and emulates
+ * as No PAT.
+ */
+ rdmsrl(MSR_IA32_CR_PAT, pat);
+ }
+
+ if (!pat) {
+ /*
+ * No PAT. Emulate the PAT table that corresponds to the two
+ * cache bits, PWT (Write Through) and PCD (Cache Disable).
+ * This setup is also the same as the BIOS default setup.
+ *
+ * PTE encoding:
+ *
+ * PCD
+ * |PWT PAT
+ * || slot
+ * 00 0 WB : _PAGE_CACHE_MODE_WB
+ * 01 1 WT : _PAGE_CACHE_MODE_WT
+ * 10 2 UC-: _PAGE_CACHE_MODE_UC_MINUS
+ * 11 3 UC : _PAGE_CACHE_MODE_UC
+ *
+ * NOTE: When WC or WP is used, it is redirected to UC- per
+ * the default setup in __cachemode2pte_tbl[].
+ */
+ pat = PAT(0, WB) | PAT(1, WT) | PAT(2, UC_MINUS) | PAT(3, UC) |
+ PAT(4, WB) | PAT(5, WT) | PAT(6, UC_MINUS) | PAT(7, UC);
+ }
+
+ __init_cache_modes(pat);
+}
+
+/**
+ * pat_init - Initialize the PAT MSR and PAT table on the current CPU
+ *
+ * This function initializes PAT MSR and PAT table with an OS-defined value
+ * to enable additional cache attributes, WC, WT and WP.
+ *
+ * This function must be called on all CPUs using the specific sequence of
+ * operations defined in Intel SDM. mtrr_rendezvous_handler() provides this
+ * procedure for PAT.
+ */
+void pat_init(void)
+{
+ u64 pat;
+ struct cpuinfo_x86 *c = &boot_cpu_data;
+
+#ifndef CONFIG_X86_PAT
+ pr_info_once("x86/PAT: PAT support disabled because CONFIG_X86_PAT is disabled in the kernel.\n");
+#endif
+
+ if (pat_disabled)
+ return;
+
+ if ((c->x86_vendor == X86_VENDOR_INTEL) &&
+ (((c->x86 == 0x6) && (c->x86_model <= 0xd)) ||
+ ((c->x86 == 0xf) && (c->x86_model <= 0x6)))) {
+ /*
+ * PAT support with the lower four entries. Intel Pentium 2,
+ * 3, M, and 4 are affected by PAT errata, which makes the
+ * upper four entries unusable. To be on the safe side, we don't
+ * use those.
+ *
+ * PTE encoding:
+ * PAT
+ * |PCD
+ * ||PWT PAT
+ * ||| slot
+ * 000 0 WB : _PAGE_CACHE_MODE_WB
+ * 001 1 WC : _PAGE_CACHE_MODE_WC
+ * 010 2 UC-: _PAGE_CACHE_MODE_UC_MINUS
+ * 011 3 UC : _PAGE_CACHE_MODE_UC
+ * PAT bit unused
+ *
+ * NOTE: When WT or WP is used, it is redirected to UC- per
+ * the default setup in __cachemode2pte_tbl[].
+ */
+ pat = PAT(0, WB) | PAT(1, WC) | PAT(2, UC_MINUS) | PAT(3, UC) |
+ PAT(4, WB) | PAT(5, WC) | PAT(6, UC_MINUS) | PAT(7, UC);
+ } else {
+ /*
+ * Full PAT support. We put WT in slot 7 to improve
+ * robustness in the presence of errata that might cause
+ * the high PAT bit to be ignored. This way, a buggy slot 7
+ * access will hit slot 3, and slot 3 is UC, so at worst
+ * we lose performance without causing a correctness issue.
+ * Pentium 4 erratum N46 is an example for such an erratum,
+ * although we try not to use PAT at all on affected CPUs.
+ *
+ * PTE encoding:
+ * PAT
+ * |PCD
+ * ||PWT PAT
+ * ||| slot
+ * 000 0 WB : _PAGE_CACHE_MODE_WB
+ * 001 1 WC : _PAGE_CACHE_MODE_WC
+ * 010 2 UC-: _PAGE_CACHE_MODE_UC_MINUS
+ * 011 3 UC : _PAGE_CACHE_MODE_UC
+ * 100 4 WB : Reserved
+ * 101 5 WP : _PAGE_CACHE_MODE_WP
+ * 110 6 UC-: Reserved
+ * 111 7 WT : _PAGE_CACHE_MODE_WT
+ *
+ * The reserved slots are unused, but mapped to their
+ * corresponding types in the presence of PAT errata.
+ */
+ pat = PAT(0, WB) | PAT(1, WC) | PAT(2, UC_MINUS) | PAT(3, UC) |
+ PAT(4, WB) | PAT(5, WP) | PAT(6, UC_MINUS) | PAT(7, WT);
+ }
+
+ if (!pat_bp_initialized) {
+ pat_bp_init(pat);
+ pat_bp_initialized = true;
+ } else {
+ pat_ap_init(pat);
+ }
+}
+
+#undef PAT
+
+static DEFINE_SPINLOCK(memtype_lock); /* protects memtype accesses */
+
+/*
+ * Does intersection of PAT memory type and MTRR memory type and returns
+ * the resulting memory type as PAT understands it.
+ * (Type in pat and mtrr will not have same value)
+ * The intersection is based on "Effective Memory Type" tables in IA-32
+ * SDM vol 3a
+ */
+static unsigned long pat_x_mtrr_type(u64 start, u64 end,
+ enum page_cache_mode req_type)
+{
+ /*
+ * Look for MTRR hint to get the effective type in case where PAT
+ * request is for WB.
+ */
+ if (req_type == _PAGE_CACHE_MODE_WB) {
+ u8 mtrr_type, uniform;
+
+ mtrr_type = mtrr_type_lookup(start, end, &uniform);
+ if (mtrr_type != MTRR_TYPE_WRBACK)
+ return _PAGE_CACHE_MODE_UC_MINUS;
+
+ return _PAGE_CACHE_MODE_WB;
+ }
+
+ return req_type;
+}
+
+struct pagerange_state {
+ unsigned long cur_pfn;
+ int ram;
+ int not_ram;
+};
+
+static int
+pagerange_is_ram_callback(unsigned long initial_pfn, unsigned long total_nr_pages, void *arg)
+{
+ struct pagerange_state *state = arg;
+
+ state->not_ram |= initial_pfn > state->cur_pfn;
+ state->ram |= total_nr_pages > 0;
+ state->cur_pfn = initial_pfn + total_nr_pages;
+
+ return state->ram && state->not_ram;
+}
+
+static int pat_pagerange_is_ram(resource_size_t start, resource_size_t end)
+{
+ int ret = 0;
+ unsigned long start_pfn = start >> PAGE_SHIFT;
+ unsigned long end_pfn = (end + PAGE_SIZE - 1) >> PAGE_SHIFT;
+ struct pagerange_state state = {start_pfn, 0, 0};
+
+ /*
+ * For legacy reasons, physical address range in the legacy ISA
+ * region is tracked as non-RAM. This will allow users of
+ * /dev/mem to map portions of legacy ISA region, even when
+ * some of those portions are listed(or not even listed) with
+ * different e820 types(RAM/reserved/..)
+ */
+ if (start_pfn < ISA_END_ADDRESS >> PAGE_SHIFT)
+ start_pfn = ISA_END_ADDRESS >> PAGE_SHIFT;
+
+ if (start_pfn < end_pfn) {
+ ret = walk_system_ram_range(start_pfn, end_pfn - start_pfn,
+ &state, pagerange_is_ram_callback);
+ }
+
+ return (ret > 0) ? -1 : (state.ram ? 1 : 0);
+}
+
+/*
+ * For RAM pages, we use page flags to mark the pages with appropriate type.
+ * The page flags are limited to four types, WB (default), WC, WT and UC-.
+ * WP request fails with -EINVAL, and UC gets redirected to UC-. Setting
+ * a new memory type is only allowed for a page mapped with the default WB
+ * type.
+ *
+ * Here we do two passes:
+ * - Find the memtype of all the pages in the range, look for any conflicts.
+ * - In case of no conflicts, set the new memtype for pages in the range.
+ */
+static int reserve_ram_pages_type(u64 start, u64 end,
+ enum page_cache_mode req_type,
+ enum page_cache_mode *new_type)
+{
+ struct page *page;
+ u64 pfn;
+
+ if (req_type == _PAGE_CACHE_MODE_WP) {
+ if (new_type)
+ *new_type = _PAGE_CACHE_MODE_UC_MINUS;
+ return -EINVAL;
+ }
+
+ if (req_type == _PAGE_CACHE_MODE_UC) {
+ /* We do not support strong UC */
+ WARN_ON_ONCE(1);
+ req_type = _PAGE_CACHE_MODE_UC_MINUS;
+ }
+
+ for (pfn = (start >> PAGE_SHIFT); pfn < (end >> PAGE_SHIFT); ++pfn) {
+ enum page_cache_mode type;
+
+ page = pfn_to_page(pfn);
+ type = get_page_memtype(page);
+ if (type != _PAGE_CACHE_MODE_WB) {
+ pr_info("x86/PAT: reserve_ram_pages_type failed [mem %#010Lx-%#010Lx], track 0x%x, req 0x%x\n",
+ start, end - 1, type, req_type);
+ if (new_type)
+ *new_type = type;
+
+ return -EBUSY;
+ }
+ }
+
+ if (new_type)
+ *new_type = req_type;
+
+ for (pfn = (start >> PAGE_SHIFT); pfn < (end >> PAGE_SHIFT); ++pfn) {
+ page = pfn_to_page(pfn);
+ set_page_memtype(page, req_type);
+ }
+ return 0;
+}
+
+static int free_ram_pages_type(u64 start, u64 end)
+{
+ struct page *page;
+ u64 pfn;
+
+ for (pfn = (start >> PAGE_SHIFT); pfn < (end >> PAGE_SHIFT); ++pfn) {
+ page = pfn_to_page(pfn);
+ set_page_memtype(page, _PAGE_CACHE_MODE_WB);
+ }
+ return 0;
+}
+
+static u64 sanitize_phys(u64 address)
+{
+ /*
+ * When changing the memtype for pages containing poison allow
+ * for a "decoy" virtual address (bit 63 clear) passed to
+ * set_memory_X(). __pa() on a "decoy" address results in a
+ * physical address with bit 63 set.
+ *
+ * Decoy addresses are not present for 32-bit builds, see
+ * set_mce_nospec().
+ */
+ if (IS_ENABLED(CONFIG_X86_64))
+ return address & __PHYSICAL_MASK;
+ return address;
+}
+
+/*
+ * req_type typically has one of the:
+ * - _PAGE_CACHE_MODE_WB
+ * - _PAGE_CACHE_MODE_WC
+ * - _PAGE_CACHE_MODE_UC_MINUS
+ * - _PAGE_CACHE_MODE_UC
+ * - _PAGE_CACHE_MODE_WT
+ *
+ * If new_type is NULL, function will return an error if it cannot reserve the
+ * region with req_type. If new_type is non-NULL, function will return
+ * available type in new_type in case of no error. In case of any error
+ * it will return a negative return value.
+ */
+int reserve_memtype(u64 start, u64 end, enum page_cache_mode req_type,
+ enum page_cache_mode *new_type)
+{
+ struct memtype *entry_new;
+ enum page_cache_mode actual_type;
+ int is_range_ram;
+ int err = 0;
+
+ start = sanitize_phys(start);
+ end = sanitize_phys(end);
+ if (start >= end) {
+ WARN(1, "%s failed: [mem %#010Lx-%#010Lx], req %s\n", __func__,
+ start, end - 1, cattr_name(req_type));
+ return -EINVAL;
+ }
+
+ if (!pat_enabled()) {
+ /* This is identical to page table setting without PAT */
+ if (new_type)
+ *new_type = req_type;
+ return 0;
+ }
+
+ /* Low ISA region is always mapped WB in page table. No need to track */
+ if (x86_platform.is_untracked_pat_range(start, end)) {
+ if (new_type)
+ *new_type = _PAGE_CACHE_MODE_WB;
+ return 0;
+ }
+
+ /*
+ * Call mtrr_lookup to get the type hint. This is an
+ * optimization for /dev/mem mmap'ers into WB memory (BIOS
+ * tools and ACPI tools). Use WB request for WB memory and use
+ * UC_MINUS otherwise.
+ */
+ actual_type = pat_x_mtrr_type(start, end, req_type);
+
+ if (new_type)
+ *new_type = actual_type;
+
+ is_range_ram = pat_pagerange_is_ram(start, end);
+ if (is_range_ram == 1) {
+
+ err = reserve_ram_pages_type(start, end, req_type, new_type);
+
+ return err;
+ } else if (is_range_ram < 0) {
+ return -EINVAL;
+ }
+
+ entry_new = kzalloc(sizeof(struct memtype), GFP_KERNEL);
+ if (!entry_new)
+ return -ENOMEM;
+
+ entry_new->start = start;
+ entry_new->end = end;
+ entry_new->type = actual_type;
+
+ spin_lock(&memtype_lock);
+
+ err = memtype_check_insert(entry_new, new_type);
+ if (err) {
+ pr_info("x86/PAT: reserve_memtype failed [mem %#010Lx-%#010Lx], track %s, req %s\n",
+ start, end - 1,
+ cattr_name(entry_new->type), cattr_name(req_type));
+ kfree(entry_new);
+ spin_unlock(&memtype_lock);
+
+ return err;
+ }
+
+ spin_unlock(&memtype_lock);
+
+ dprintk("reserve_memtype added [mem %#010Lx-%#010Lx], track %s, req %s, ret %s\n",
+ start, end - 1, cattr_name(entry_new->type), cattr_name(req_type),
+ new_type ? cattr_name(*new_type) : "-");
+
+ return err;
+}
+
+int free_memtype(u64 start, u64 end)
+{
+ int is_range_ram;
+ struct memtype *entry_old;
+
+ if (!pat_enabled())
+ return 0;
+
+ start = sanitize_phys(start);
+ end = sanitize_phys(end);
+
+ /* Low ISA region is always mapped WB. No need to track */
+ if (x86_platform.is_untracked_pat_range(start, end))
+ return 0;
+
+ is_range_ram = pat_pagerange_is_ram(start, end);
+ if (is_range_ram == 1)
+ return free_ram_pages_type(start, end);
+ if (is_range_ram < 0)
+ return -EINVAL;
+
+ spin_lock(&memtype_lock);
+ entry_old = memtype_erase(start, end);
+ spin_unlock(&memtype_lock);
+
+ if (IS_ERR(entry_old)) {
+ pr_info("x86/PAT: %s:%d freeing invalid memtype [mem %#010Lx-%#010Lx]\n",
+ current->comm, current->pid, start, end - 1);
+ return -EINVAL;
+ }
+
+ kfree(entry_old);
+
+ dprintk("free_memtype request [mem %#010Lx-%#010Lx]\n", start, end - 1);
+
+ return 0;
+}
+
+
+/**
+ * lookup_memtype - Looksup the memory type for a physical address
+ * @paddr: physical address of which memory type needs to be looked up
+ *
+ * Only to be called when PAT is enabled
+ *
+ * Returns _PAGE_CACHE_MODE_WB, _PAGE_CACHE_MODE_WC, _PAGE_CACHE_MODE_UC_MINUS
+ * or _PAGE_CACHE_MODE_WT.
+ */
+static enum page_cache_mode lookup_memtype(u64 paddr)
+{
+ enum page_cache_mode rettype = _PAGE_CACHE_MODE_WB;
+ struct memtype *entry;
+
+ if (x86_platform.is_untracked_pat_range(paddr, paddr + PAGE_SIZE))
+ return rettype;
+
+ if (pat_pagerange_is_ram(paddr, paddr + PAGE_SIZE)) {
+ struct page *page;
+
+ page = pfn_to_page(paddr >> PAGE_SHIFT);
+ return get_page_memtype(page);
+ }
+
+ spin_lock(&memtype_lock);
+
+ entry = memtype_lookup(paddr);
+ if (entry != NULL)
+ rettype = entry->type;
+ else
+ rettype = _PAGE_CACHE_MODE_UC_MINUS;
+
+ spin_unlock(&memtype_lock);
+
+ return rettype;
+}
+
+/**
+ * pat_pfn_immune_to_uc_mtrr - Check whether the PAT memory type
+ * of @pfn cannot be overridden by UC MTRR memory type.
+ *
+ * Only to be called when PAT is enabled.
+ *
+ * Returns true, if the PAT memory type of @pfn is UC, UC-, or WC.
+ * Returns false in other cases.
+ */
+bool pat_pfn_immune_to_uc_mtrr(unsigned long pfn)
+{
+ enum page_cache_mode cm = lookup_memtype(PFN_PHYS(pfn));
+
+ return cm == _PAGE_CACHE_MODE_UC ||
+ cm == _PAGE_CACHE_MODE_UC_MINUS ||
+ cm == _PAGE_CACHE_MODE_WC;
+}
+EXPORT_SYMBOL_GPL(pat_pfn_immune_to_uc_mtrr);
+
+/**
+ * io_reserve_memtype - Request a memory type mapping for a region of memory
+ * @start: start (physical address) of the region
+ * @end: end (physical address) of the region
+ * @type: A pointer to memtype, with requested type. On success, requested
+ * or any other compatible type that was available for the region is returned
+ *
+ * On success, returns 0
+ * On failure, returns non-zero
+ */
+int io_reserve_memtype(resource_size_t start, resource_size_t end,
+ enum page_cache_mode *type)
+{
+ resource_size_t size = end - start;
+ enum page_cache_mode req_type = *type;
+ enum page_cache_mode new_type;
+ int ret;
+
+ WARN_ON_ONCE(iomem_map_sanity_check(start, size));
+
+ ret = reserve_memtype(start, end, req_type, &new_type);
+ if (ret)
+ goto out_err;
+
+ if (!is_new_memtype_allowed(start, size, req_type, new_type))
+ goto out_free;
+
+ if (kernel_map_sync_memtype(start, size, new_type) < 0)
+ goto out_free;
+
+ *type = new_type;
+ return 0;
+
+out_free:
+ free_memtype(start, end);
+ ret = -EBUSY;
+out_err:
+ return ret;
+}
+
+/**
+ * io_free_memtype - Release a memory type mapping for a region of memory
+ * @start: start (physical address) of the region
+ * @end: end (physical address) of the region
+ */
+void io_free_memtype(resource_size_t start, resource_size_t end)
+{
+ free_memtype(start, end);
+}
+
+int arch_io_reserve_memtype_wc(resource_size_t start, resource_size_t size)
+{
+ enum page_cache_mode type = _PAGE_CACHE_MODE_WC;
+
+ return io_reserve_memtype(start, start + size, &type);
+}
+EXPORT_SYMBOL(arch_io_reserve_memtype_wc);
+
+void arch_io_free_memtype_wc(resource_size_t start, resource_size_t size)
+{
+ io_free_memtype(start, start + size);
+}
+EXPORT_SYMBOL(arch_io_free_memtype_wc);
+
+pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn,
+ unsigned long size, pgprot_t vma_prot)
+{
+ if (!phys_mem_access_encrypted(pfn << PAGE_SHIFT, size))
+ vma_prot = pgprot_decrypted(vma_prot);
+
+ return vma_prot;
+}
+
+#ifdef CONFIG_STRICT_DEVMEM
+/* This check is done in drivers/char/mem.c in case of STRICT_DEVMEM */
+static inline int range_is_allowed(unsigned long pfn, unsigned long size)
+{
+ return 1;
+}
+#else
+/* This check is needed to avoid cache aliasing when PAT is enabled */
+static inline int range_is_allowed(unsigned long pfn, unsigned long size)
+{
+ u64 from = ((u64)pfn) << PAGE_SHIFT;
+ u64 to = from + size;
+ u64 cursor = from;
+
+ if (!pat_enabled())
+ return 1;
+
+ while (cursor < to) {
+ if (!devmem_is_allowed(pfn))
+ return 0;
+ cursor += PAGE_SIZE;
+ pfn++;
+ }
+ return 1;
+}
+#endif /* CONFIG_STRICT_DEVMEM */
+
+int phys_mem_access_prot_allowed(struct file *file, unsigned long pfn,
+ unsigned long size, pgprot_t *vma_prot)
+{
+ enum page_cache_mode pcm = _PAGE_CACHE_MODE_WB;
+
+ if (!range_is_allowed(pfn, size))
+ return 0;
+
+ if (file->f_flags & O_DSYNC)
+ pcm = _PAGE_CACHE_MODE_UC_MINUS;
+
+ *vma_prot = __pgprot((pgprot_val(*vma_prot) & ~_PAGE_CACHE_MASK) |
+ cachemode2protval(pcm));
+ return 1;
+}
+
+/*
+ * Change the memory type for the physical address range in kernel identity
+ * mapping space if that range is a part of identity map.
+ */
+int kernel_map_sync_memtype(u64 base, unsigned long size,
+ enum page_cache_mode pcm)
+{
+ unsigned long id_sz;
+
+ if (base > __pa(high_memory-1))
+ return 0;
+
+ /*
+ * Some areas in the middle of the kernel identity range
+ * are not mapped, for example the PCI space.
+ */
+ if (!page_is_ram(base >> PAGE_SHIFT))
+ return 0;
+
+ id_sz = (__pa(high_memory-1) <= base + size) ?
+ __pa(high_memory) - base : size;
+
+ if (ioremap_change_attr((unsigned long)__va(base), id_sz, pcm) < 0) {
+ pr_info("x86/PAT: %s:%d ioremap_change_attr failed %s for [mem %#010Lx-%#010Lx]\n",
+ current->comm, current->pid,
+ cattr_name(pcm),
+ base, (unsigned long long)(base + size-1));
+ return -EINVAL;
+ }
+ return 0;
+}
+
+/*
+ * Internal interface to reserve a range of physical memory with prot.
+ * Reserved non RAM regions only and after successful reserve_memtype,
+ * this func also keeps identity mapping (if any) in sync with this new prot.
+ */
+static int reserve_pfn_range(u64 paddr, unsigned long size, pgprot_t *vma_prot,
+ int strict_prot)
+{
+ int is_ram = 0;
+ int ret;
+ enum page_cache_mode want_pcm = pgprot2cachemode(*vma_prot);
+ enum page_cache_mode pcm = want_pcm;
+
+ is_ram = pat_pagerange_is_ram(paddr, paddr + size);
+
+ /*
+ * reserve_pfn_range() for RAM pages. We do not refcount to keep
+ * track of number of mappings of RAM pages. We can assert that
+ * the type requested matches the type of first page in the range.
+ */
+ if (is_ram) {
+ if (!pat_enabled())
+ return 0;
+
+ pcm = lookup_memtype(paddr);
+ if (want_pcm != pcm) {
+ pr_warn("x86/PAT: %s:%d map pfn RAM range req %s for [mem %#010Lx-%#010Lx], got %s\n",
+ current->comm, current->pid,
+ cattr_name(want_pcm),
+ (unsigned long long)paddr,
+ (unsigned long long)(paddr + size - 1),
+ cattr_name(pcm));
+ *vma_prot = __pgprot((pgprot_val(*vma_prot) &
+ (~_PAGE_CACHE_MASK)) |
+ cachemode2protval(pcm));
+ }
+ return 0;
+ }
+
+ ret = reserve_memtype(paddr, paddr + size, want_pcm, &pcm);
+ if (ret)
+ return ret;
+
+ if (pcm != want_pcm) {
+ if (strict_prot ||
+ !is_new_memtype_allowed(paddr, size, want_pcm, pcm)) {
+ free_memtype(paddr, paddr + size);
+ pr_err("x86/PAT: %s:%d map pfn expected mapping type %s for [mem %#010Lx-%#010Lx], got %s\n",
+ current->comm, current->pid,
+ cattr_name(want_pcm),
+ (unsigned long long)paddr,
+ (unsigned long long)(paddr + size - 1),
+ cattr_name(pcm));
+ return -EINVAL;
+ }
+ /*
+ * We allow returning different type than the one requested in
+ * non strict case.
+ */
+ *vma_prot = __pgprot((pgprot_val(*vma_prot) &
+ (~_PAGE_CACHE_MASK)) |
+ cachemode2protval(pcm));
+ }
+
+ if (kernel_map_sync_memtype(paddr, size, pcm) < 0) {
+ free_memtype(paddr, paddr + size);
+ return -EINVAL;
+ }
+ return 0;
+}
+
+/*
+ * Internal interface to free a range of physical memory.
+ * Frees non RAM regions only.
+ */
+static void free_pfn_range(u64 paddr, unsigned long size)
+{
+ int is_ram;
+
+ is_ram = pat_pagerange_is_ram(paddr, paddr + size);
+ if (is_ram == 0)
+ free_memtype(paddr, paddr + size);
+}
+
+/*
+ * track_pfn_copy is called when vma that is covering the pfnmap gets
+ * copied through copy_page_range().
+ *
+ * If the vma has a linear pfn mapping for the entire range, we get the prot
+ * from pte and reserve the entire vma range with single reserve_pfn_range call.
+ */
+int track_pfn_copy(struct vm_area_struct *vma)
+{
+ resource_size_t paddr;
+ unsigned long prot;
+ unsigned long vma_size = vma->vm_end - vma->vm_start;
+ pgprot_t pgprot;
+
+ if (vma->vm_flags & VM_PAT) {
+ /*
+ * reserve the whole chunk covered by vma. We need the
+ * starting address and protection from pte.
+ */
+ if (follow_phys(vma, vma->vm_start, 0, &prot, &paddr)) {
+ WARN_ON_ONCE(1);
+ return -EINVAL;
+ }
+ pgprot = __pgprot(prot);
+ return reserve_pfn_range(paddr, vma_size, &pgprot, 1);
+ }
+
+ return 0;
+}
+
+/*
+ * prot is passed in as a parameter for the new mapping. If the vma has
+ * a linear pfn mapping for the entire range, or no vma is provided,
+ * reserve the entire pfn + size range with single reserve_pfn_range
+ * call.
+ */
+int track_pfn_remap(struct vm_area_struct *vma, pgprot_t *prot,
+ unsigned long pfn, unsigned long addr, unsigned long size)
+{
+ resource_size_t paddr = (resource_size_t)pfn << PAGE_SHIFT;
+ enum page_cache_mode pcm;
+
+ /* reserve the whole chunk starting from paddr */
+ if (!vma || (addr == vma->vm_start
+ && size == (vma->vm_end - vma->vm_start))) {
+ int ret;
+
+ ret = reserve_pfn_range(paddr, size, prot, 0);
+ if (ret == 0 && vma)
+ vma->vm_flags |= VM_PAT;
+ return ret;
+ }
+
+ if (!pat_enabled())
+ return 0;
+
+ /*
+ * For anything smaller than the vma size we set prot based on the
+ * lookup.
+ */
+ pcm = lookup_memtype(paddr);
+
+ /* Check memtype for the remaining pages */
+ while (size > PAGE_SIZE) {
+ size -= PAGE_SIZE;
+ paddr += PAGE_SIZE;
+ if (pcm != lookup_memtype(paddr))
+ return -EINVAL;
+ }
+
+ *prot = __pgprot((pgprot_val(*prot) & (~_PAGE_CACHE_MASK)) |
+ cachemode2protval(pcm));
+
+ return 0;
+}
+
+void track_pfn_insert(struct vm_area_struct *vma, pgprot_t *prot, pfn_t pfn)
+{
+ enum page_cache_mode pcm;
+
+ if (!pat_enabled())
+ return;
+
+ /* Set prot based on lookup */
+ pcm = lookup_memtype(pfn_t_to_phys(pfn));
+ *prot = __pgprot((pgprot_val(*prot) & (~_PAGE_CACHE_MASK)) |
+ cachemode2protval(pcm));
+}
+
+/*
+ * untrack_pfn is called while unmapping a pfnmap for a region.
+ * untrack can be called for a specific region indicated by pfn and size or
+ * can be for the entire vma (in which case pfn, size are zero).
+ */
+void untrack_pfn(struct vm_area_struct *vma, unsigned long pfn,
+ unsigned long size)
+{
+ resource_size_t paddr;
+ unsigned long prot;
+
+ if (vma && !(vma->vm_flags & VM_PAT))
+ return;
+
+ /* free the chunk starting from pfn or the whole chunk */
+ paddr = (resource_size_t)pfn << PAGE_SHIFT;
+ if (!paddr && !size) {
+ if (follow_phys(vma, vma->vm_start, 0, &prot, &paddr)) {
+ WARN_ON_ONCE(1);
+ return;
+ }
+
+ size = vma->vm_end - vma->vm_start;
+ }
+ free_pfn_range(paddr, size);
+ if (vma)
+ vma->vm_flags &= ~VM_PAT;
+}
+
+/*
+ * untrack_pfn_moved is called, while mremapping a pfnmap for a new region,
+ * with the old vma after its pfnmap page table has been removed. The new
+ * vma has a new pfnmap to the same pfn & cache type with VM_PAT set.
+ */
+void untrack_pfn_moved(struct vm_area_struct *vma)
+{
+ vma->vm_flags &= ~VM_PAT;
+}
+
+pgprot_t pgprot_writecombine(pgprot_t prot)
+{
+ return __pgprot(pgprot_val(prot) |
+ cachemode2protval(_PAGE_CACHE_MODE_WC));
+}
+EXPORT_SYMBOL_GPL(pgprot_writecombine);
+
+pgprot_t pgprot_writethrough(pgprot_t prot)
+{
+ return __pgprot(pgprot_val(prot) |
+ cachemode2protval(_PAGE_CACHE_MODE_WT));
+}
+EXPORT_SYMBOL_GPL(pgprot_writethrough);
+
+#if defined(CONFIG_DEBUG_FS) && defined(CONFIG_X86_PAT)
+
+/*
+ * We are allocating a temporary printout-entry to be passed
+ * between seq_start()/next() and seq_show():
+ */
+static struct memtype *memtype_get_idx(loff_t pos)
+{
+ struct memtype *entry_print;
+ int ret;
+
+ entry_print = kzalloc(sizeof(struct memtype), GFP_KERNEL);
+ if (!entry_print)
+ return NULL;
+
+ spin_lock(&memtype_lock);
+ ret = memtype_copy_nth_element(entry_print, pos);
+ spin_unlock(&memtype_lock);
+
+ /* Free it on error: */
+ if (ret) {
+ kfree(entry_print);
+ return NULL;
+ }
+
+ return entry_print;
+}
+
+static void *memtype_seq_start(struct seq_file *seq, loff_t *pos)
+{
+ if (*pos == 0) {
+ ++*pos;
+ seq_puts(seq, "PAT memtype list:\n");
+ }
+
+ return memtype_get_idx(*pos);
+}
+
+static void *memtype_seq_next(struct seq_file *seq, void *v, loff_t *pos)
+{
+ ++*pos;
+ return memtype_get_idx(*pos);
+}
+
+static void memtype_seq_stop(struct seq_file *seq, void *v)
+{
+}
+
+static int memtype_seq_show(struct seq_file *seq, void *v)
+{
+ struct memtype *entry_print = (struct memtype *)v;
+
+ seq_printf(seq, "PAT: [mem 0x%016Lx-0x%016Lx] %s\n",
+ entry_print->start,
+ entry_print->end,
+ cattr_name(entry_print->type));
+
+ kfree(entry_print);
+
+ return 0;
+}
+
+static const struct seq_operations memtype_seq_ops = {
+ .start = memtype_seq_start,
+ .next = memtype_seq_next,
+ .stop = memtype_seq_stop,
+ .show = memtype_seq_show,
+};
+
+static int memtype_seq_open(struct inode *inode, struct file *file)
+{
+ return seq_open(file, &memtype_seq_ops);
+}
+
+static const struct file_operations memtype_fops = {
+ .open = memtype_seq_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = seq_release,
+};
+
+static int __init pat_memtype_list_init(void)
+{
+ if (pat_enabled()) {
+ debugfs_create_file("pat_memtype_list", S_IRUSR,
+ arch_debugfs_dir, NULL, &memtype_fops);
+ }
+ return 0;
+}
+late_initcall(pat_memtype_list_init);
+
+#endif /* CONFIG_DEBUG_FS && CONFIG_X86_PAT */
diff --git a/arch/x86/mm/pat/memtype.h b/arch/x86/mm/pat/memtype.h
new file mode 100644
index 0000000..cacecdb
--- /dev/null
+++ b/arch/x86/mm/pat/memtype.h
@@ -0,0 +1,49 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __MEMTYPE_H_
+#define __MEMTYPE_H_
+
+extern int pat_debug_enable;
+
+#define dprintk(fmt, arg...) \
+ do { if (pat_debug_enable) pr_info("x86/PAT: " fmt, ##arg); } while (0)
+
+struct memtype {
+ u64 start;
+ u64 end;
+ u64 subtree_max_end;
+ enum page_cache_mode type;
+ struct rb_node rb;
+};
+
+static inline char *cattr_name(enum page_cache_mode pcm)
+{
+ switch (pcm) {
+ case _PAGE_CACHE_MODE_UC: return "uncached";
+ case _PAGE_CACHE_MODE_UC_MINUS: return "uncached-minus";
+ case _PAGE_CACHE_MODE_WB: return "write-back";
+ case _PAGE_CACHE_MODE_WC: return "write-combining";
+ case _PAGE_CACHE_MODE_WT: return "write-through";
+ case _PAGE_CACHE_MODE_WP: return "write-protected";
+ default: return "broken";
+ }
+}
+
+#ifdef CONFIG_X86_PAT
+extern int memtype_check_insert(struct memtype *entry_new,
+ enum page_cache_mode *new_type);
+extern struct memtype *memtype_erase(u64 start, u64 end);
+extern struct memtype *memtype_lookup(u64 addr);
+extern int memtype_copy_nth_element(struct memtype *entry_out, loff_t pos);
+#else
+static inline int memtype_check_insert(struct memtype *entry_new,
+ enum page_cache_mode *new_type)
+{ return 0; }
+static inline struct memtype *memtype_erase(u64 start, u64 end)
+{ return NULL; }
+static inline struct memtype *memtype_lookup(u64 addr)
+{ return NULL; }
+static inline int memtype_copy_nth_element(struct memtype *out, loff_t pos)
+{ return 0; }
+#endif
+
+#endif /* __MEMTYPE_H_ */
diff --git a/arch/x86/mm/pat/memtype_interval.c b/arch/x86/mm/pat/memtype_interval.c
new file mode 100644
index 0000000..a7fbbdd
--- /dev/null
+++ b/arch/x86/mm/pat/memtype_interval.c
@@ -0,0 +1,194 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Handle caching attributes in page tables (PAT)
+ *
+ * Authors: Venkatesh Pallipadi <venkatesh.pallipadi@...el.com>
+ * Suresh B Siddha <suresh.b.siddha@...el.com>
+ *
+ * Interval tree used to store the PAT memory type reservations.
+ */
+
+#include <linux/seq_file.h>
+#include <linux/debugfs.h>
+#include <linux/kernel.h>
+#include <linux/interval_tree_generic.h>
+#include <linux/sched.h>
+#include <linux/gfp.h>
+
+#include <asm/pgtable.h>
+#include <asm/pat.h>
+
+#include "memtype.h"
+
+/*
+ * The memtype tree keeps track of memory type for specific
+ * physical memory areas. Without proper tracking, conflicting memory
+ * types in different mappings can cause CPU cache corruption.
+ *
+ * The tree is an interval tree (augmented rbtree) which tree is ordered
+ * by the starting address. The tree can contain multiple entries for
+ * different regions which overlap. All the aliases have the same
+ * cache attributes of course, as enforced by the PAT logic.
+ *
+ * memtype_lock protects the rbtree.
+ */
+
+static inline u64 interval_start(struct memtype *entry)
+{
+ return entry->start;
+}
+
+static inline u64 interval_end(struct memtype *entry)
+{
+ return entry->end - 1;
+}
+
+INTERVAL_TREE_DEFINE(struct memtype, rb, u64, subtree_max_end,
+ interval_start, interval_end,
+ static, interval)
+
+static struct rb_root_cached memtype_rbroot = RB_ROOT_CACHED;
+
+enum {
+ MEMTYPE_EXACT_MATCH = 0,
+ MEMTYPE_END_MATCH = 1
+};
+
+static struct memtype *memtype_match(u64 start, u64 end, int match_type)
+{
+ struct memtype *entry_match;
+
+ entry_match = interval_iter_first(&memtype_rbroot, start, end-1);
+
+ while (entry_match != NULL && entry_match->start < end) {
+ if ((match_type == MEMTYPE_EXACT_MATCH) &&
+ (entry_match->start == start) && (entry_match->end == end))
+ return entry_match;
+
+ if ((match_type == MEMTYPE_END_MATCH) &&
+ (entry_match->start < start) && (entry_match->end == end))
+ return entry_match;
+
+ entry_match = interval_iter_next(entry_match, start, end-1);
+ }
+
+ return NULL; /* Returns NULL if there is no match */
+}
+
+static int memtype_check_conflict(u64 start, u64 end,
+ enum page_cache_mode reqtype,
+ enum page_cache_mode *newtype)
+{
+ struct memtype *entry_match;
+ enum page_cache_mode found_type = reqtype;
+
+ entry_match = interval_iter_first(&memtype_rbroot, start, end-1);
+ if (entry_match == NULL)
+ goto success;
+
+ if (entry_match->type != found_type && newtype == NULL)
+ goto failure;
+
+ dprintk("Overlap at 0x%Lx-0x%Lx\n", entry_match->start, entry_match->end);
+ found_type = entry_match->type;
+
+ entry_match = interval_iter_next(entry_match, start, end-1);
+ while (entry_match) {
+ if (entry_match->type != found_type)
+ goto failure;
+
+ entry_match = interval_iter_next(entry_match, start, end-1);
+ }
+success:
+ if (newtype)
+ *newtype = found_type;
+
+ return 0;
+
+failure:
+ pr_info("x86/PAT: %s:%d conflicting memory types %Lx-%Lx %s<->%s\n",
+ current->comm, current->pid, start, end,
+ cattr_name(found_type), cattr_name(entry_match->type));
+
+ return -EBUSY;
+}
+
+int memtype_check_insert(struct memtype *entry_new, enum page_cache_mode *ret_type)
+{
+ int err = 0;
+
+ err = memtype_check_conflict(entry_new->start, entry_new->end, entry_new->type, ret_type);
+ if (err)
+ return err;
+
+ if (ret_type)
+ entry_new->type = *ret_type;
+
+ interval_insert(entry_new, &memtype_rbroot);
+ return 0;
+}
+
+struct memtype *memtype_erase(u64 start, u64 end)
+{
+ struct memtype *entry_old;
+
+ /*
+ * Since the memtype_rbroot tree allows overlapping ranges,
+ * memtype_erase() checks with EXACT_MATCH first, i.e. free
+ * a whole node for the munmap case. If no such entry is found,
+ * it then checks with END_MATCH, i.e. shrink the size of a node
+ * from the end for the mremap case.
+ */
+ entry_old = memtype_match(start, end, MEMTYPE_EXACT_MATCH);
+ if (!entry_old) {
+ entry_old = memtype_match(start, end, MEMTYPE_END_MATCH);
+ if (!entry_old)
+ return ERR_PTR(-EINVAL);
+ }
+
+ if (entry_old->start == start) {
+ /* munmap: erase this node */
+ interval_remove(entry_old, &memtype_rbroot);
+ } else {
+ /* mremap: update the end value of this node */
+ interval_remove(entry_old, &memtype_rbroot);
+ entry_old->end = start;
+ interval_insert(entry_old, &memtype_rbroot);
+
+ return NULL;
+ }
+
+ return entry_old;
+}
+
+struct memtype *memtype_lookup(u64 addr)
+{
+ return interval_iter_first(&memtype_rbroot, addr, addr + PAGE_SIZE-1);
+}
+
+/*
+ * Debugging helper, copy the Nth entry of the tree into a
+ * a copy for printout. This allows us to print out the tree
+ * via debugfs, without holding the memtype_lock too long:
+ */
+#ifdef CONFIG_DEBUG_FS
+int memtype_copy_nth_element(struct memtype *entry_out, loff_t pos)
+{
+ struct memtype *entry_match;
+ int i = 1;
+
+ entry_match = interval_iter_first(&memtype_rbroot, 0, ULONG_MAX);
+
+ while (entry_match && pos != i) {
+ entry_match = interval_iter_next(entry_match, 0, ULONG_MAX);
+ i++;
+ }
+
+ if (entry_match) { /* pos == i */
+ *entry_out = *entry_match;
+ return 0;
+ } else {
+ return 1;
+ }
+}
+#endif
diff --git a/arch/x86/mm/pat/set_memory.c b/arch/x86/mm/pat/set_memory.c
new file mode 100644
index 0000000..8fbefee
--- /dev/null
+++ b/arch/x86/mm/pat/set_memory.c
@@ -0,0 +1,2285 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright 2002 Andi Kleen, SuSE Labs.
+ * Thanks to Ben LaHaise for precious feedback.
+ */
+#include <linux/highmem.h>
+#include <linux/memblock.h>
+#include <linux/sched.h>
+#include <linux/mm.h>
+#include <linux/interrupt.h>
+#include <linux/seq_file.h>
+#include <linux/debugfs.h>
+#include <linux/pfn.h>
+#include <linux/percpu.h>
+#include <linux/gfp.h>
+#include <linux/pci.h>
+#include <linux/vmalloc.h>
+
+#include <asm/e820/api.h>
+#include <asm/processor.h>
+#include <asm/tlbflush.h>
+#include <asm/sections.h>
+#include <asm/setup.h>
+#include <linux/uaccess.h>
+#include <asm/pgalloc.h>
+#include <asm/proto.h>
+#include <asm/pat.h>
+#include <asm/set_memory.h>
+
+#include "../mm_internal.h"
+
+/*
+ * The current flushing context - we pass it instead of 5 arguments:
+ */
+struct cpa_data {
+ unsigned long *vaddr;
+ pgd_t *pgd;
+ pgprot_t mask_set;
+ pgprot_t mask_clr;
+ unsigned long numpages;
+ unsigned long curpage;
+ unsigned long pfn;
+ unsigned int flags;
+ unsigned int force_split : 1,
+ force_static_prot : 1;
+ struct page **pages;
+};
+
+enum cpa_warn {
+ CPA_CONFLICT,
+ CPA_PROTECT,
+ CPA_DETECT,
+};
+
+static const int cpa_warn_level = CPA_PROTECT;
+
+/*
+ * Serialize cpa() (for !DEBUG_PAGEALLOC which uses large identity mappings)
+ * using cpa_lock. So that we don't allow any other cpu, with stale large tlb
+ * entries change the page attribute in parallel to some other cpu
+ * splitting a large page entry along with changing the attribute.
+ */
+static DEFINE_SPINLOCK(cpa_lock);
+
+#define CPA_FLUSHTLB 1
+#define CPA_ARRAY 2
+#define CPA_PAGES_ARRAY 4
+#define CPA_NO_CHECK_ALIAS 8 /* Do not search for aliases */
+
+#ifdef CONFIG_PROC_FS
+static unsigned long direct_pages_count[PG_LEVEL_NUM];
+
+void update_page_count(int level, unsigned long pages)
+{
+ /* Protect against CPA */
+ spin_lock(&pgd_lock);
+ direct_pages_count[level] += pages;
+ spin_unlock(&pgd_lock);
+}
+
+static void split_page_count(int level)
+{
+ if (direct_pages_count[level] == 0)
+ return;
+
+ direct_pages_count[level]--;
+ direct_pages_count[level - 1] += PTRS_PER_PTE;
+}
+
+void arch_report_meminfo(struct seq_file *m)
+{
+ seq_printf(m, "DirectMap4k: %8lu kB\n",
+ direct_pages_count[PG_LEVEL_4K] << 2);
+#if defined(CONFIG_X86_64) || defined(CONFIG_X86_PAE)
+ seq_printf(m, "DirectMap2M: %8lu kB\n",
+ direct_pages_count[PG_LEVEL_2M] << 11);
+#else
+ seq_printf(m, "DirectMap4M: %8lu kB\n",
+ direct_pages_count[PG_LEVEL_2M] << 12);
+#endif
+ if (direct_gbpages)
+ seq_printf(m, "DirectMap1G: %8lu kB\n",
+ direct_pages_count[PG_LEVEL_1G] << 20);
+}
+#else
+static inline void split_page_count(int level) { }
+#endif
+
+#ifdef CONFIG_X86_CPA_STATISTICS
+
+static unsigned long cpa_1g_checked;
+static unsigned long cpa_1g_sameprot;
+static unsigned long cpa_1g_preserved;
+static unsigned long cpa_2m_checked;
+static unsigned long cpa_2m_sameprot;
+static unsigned long cpa_2m_preserved;
+static unsigned long cpa_4k_install;
+
+static inline void cpa_inc_1g_checked(void)
+{
+ cpa_1g_checked++;
+}
+
+static inline void cpa_inc_2m_checked(void)
+{
+ cpa_2m_checked++;
+}
+
+static inline void cpa_inc_4k_install(void)
+{
+ cpa_4k_install++;
+}
+
+static inline void cpa_inc_lp_sameprot(int level)
+{
+ if (level == PG_LEVEL_1G)
+ cpa_1g_sameprot++;
+ else
+ cpa_2m_sameprot++;
+}
+
+static inline void cpa_inc_lp_preserved(int level)
+{
+ if (level == PG_LEVEL_1G)
+ cpa_1g_preserved++;
+ else
+ cpa_2m_preserved++;
+}
+
+static int cpastats_show(struct seq_file *m, void *p)
+{
+ seq_printf(m, "1G pages checked: %16lu\n", cpa_1g_checked);
+ seq_printf(m, "1G pages sameprot: %16lu\n", cpa_1g_sameprot);
+ seq_printf(m, "1G pages preserved: %16lu\n", cpa_1g_preserved);
+ seq_printf(m, "2M pages checked: %16lu\n", cpa_2m_checked);
+ seq_printf(m, "2M pages sameprot: %16lu\n", cpa_2m_sameprot);
+ seq_printf(m, "2M pages preserved: %16lu\n", cpa_2m_preserved);
+ seq_printf(m, "4K pages set-checked: %16lu\n", cpa_4k_install);
+ return 0;
+}
+
+static int cpastats_open(struct inode *inode, struct file *file)
+{
+ return single_open(file, cpastats_show, NULL);
+}
+
+static const struct file_operations cpastats_fops = {
+ .open = cpastats_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = single_release,
+};
+
+static int __init cpa_stats_init(void)
+{
+ debugfs_create_file("cpa_stats", S_IRUSR, arch_debugfs_dir, NULL,
+ &cpastats_fops);
+ return 0;
+}
+late_initcall(cpa_stats_init);
+#else
+static inline void cpa_inc_1g_checked(void) { }
+static inline void cpa_inc_2m_checked(void) { }
+static inline void cpa_inc_4k_install(void) { }
+static inline void cpa_inc_lp_sameprot(int level) { }
+static inline void cpa_inc_lp_preserved(int level) { }
+#endif
+
+
+static inline int
+within(unsigned long addr, unsigned long start, unsigned long end)
+{
+ return addr >= start && addr < end;
+}
+
+static inline int
+within_inclusive(unsigned long addr, unsigned long start, unsigned long end)
+{
+ return addr >= start && addr <= end;
+}
+
+#ifdef CONFIG_X86_64
+
+static inline unsigned long highmap_start_pfn(void)
+{
+ return __pa_symbol(_text) >> PAGE_SHIFT;
+}
+
+static inline unsigned long highmap_end_pfn(void)
+{
+ /* Do not reference physical address outside the kernel. */
+ return __pa_symbol(roundup(_brk_end, PMD_SIZE) - 1) >> PAGE_SHIFT;
+}
+
+static bool __cpa_pfn_in_highmap(unsigned long pfn)
+{
+ /*
+ * Kernel text has an alias mapping at a high address, known
+ * here as "highmap".
+ */
+ return within_inclusive(pfn, highmap_start_pfn(), highmap_end_pfn());
+}
+
+#else
+
+static bool __cpa_pfn_in_highmap(unsigned long pfn)
+{
+ /* There is no highmap on 32-bit */
+ return false;
+}
+
+#endif
+
+/*
+ * See set_mce_nospec().
+ *
+ * Machine check recovery code needs to change cache mode of poisoned pages to
+ * UC to avoid speculative access logging another error. But passing the
+ * address of the 1:1 mapping to set_memory_uc() is a fine way to encourage a
+ * speculative access. So we cheat and flip the top bit of the address. This
+ * works fine for the code that updates the page tables. But at the end of the
+ * process we need to flush the TLB and cache and the non-canonical address
+ * causes a #GP fault when used by the INVLPG and CLFLUSH instructions.
+ *
+ * But in the common case we already have a canonical address. This code
+ * will fix the top bit if needed and is a no-op otherwise.
+ */
+static inline unsigned long fix_addr(unsigned long addr)
+{
+#ifdef CONFIG_X86_64
+ return (long)(addr << 1) >> 1;
+#else
+ return addr;
+#endif
+}
+
+static unsigned long __cpa_addr(struct cpa_data *cpa, unsigned long idx)
+{
+ if (cpa->flags & CPA_PAGES_ARRAY) {
+ struct page *page = cpa->pages[idx];
+
+ if (unlikely(PageHighMem(page)))
+ return 0;
+
+ return (unsigned long)page_address(page);
+ }
+
+ if (cpa->flags & CPA_ARRAY)
+ return cpa->vaddr[idx];
+
+ return *cpa->vaddr + idx * PAGE_SIZE;
+}
+
+/*
+ * Flushing functions
+ */
+
+static void clflush_cache_range_opt(void *vaddr, unsigned int size)
+{
+ const unsigned long clflush_size = boot_cpu_data.x86_clflush_size;
+ void *p = (void *)((unsigned long)vaddr & ~(clflush_size - 1));
+ void *vend = vaddr + size;
+
+ if (p >= vend)
+ return;
+
+ for (; p < vend; p += clflush_size)
+ clflushopt(p);
+}
+
+/**
+ * clflush_cache_range - flush a cache range with clflush
+ * @vaddr: virtual start address
+ * @size: number of bytes to flush
+ *
+ * CLFLUSHOPT is an unordered instruction which needs fencing with MFENCE or
+ * SFENCE to avoid ordering issues.
+ */
+void clflush_cache_range(void *vaddr, unsigned int size)
+{
+ mb();
+ clflush_cache_range_opt(vaddr, size);
+ mb();
+}
+EXPORT_SYMBOL_GPL(clflush_cache_range);
+
+void arch_invalidate_pmem(void *addr, size_t size)
+{
+ clflush_cache_range(addr, size);
+}
+EXPORT_SYMBOL_GPL(arch_invalidate_pmem);
+
+static void __cpa_flush_all(void *arg)
+{
+ unsigned long cache = (unsigned long)arg;
+
+ /*
+ * Flush all to work around Errata in early athlons regarding
+ * large page flushing.
+ */
+ __flush_tlb_all();
+
+ if (cache && boot_cpu_data.x86 >= 4)
+ wbinvd();
+}
+
+static void cpa_flush_all(unsigned long cache)
+{
+ BUG_ON(irqs_disabled() && !early_boot_irqs_disabled);
+
+ on_each_cpu(__cpa_flush_all, (void *) cache, 1);
+}
+
+void __cpa_flush_tlb(void *data)
+{
+ struct cpa_data *cpa = data;
+ unsigned int i;
+
+ for (i = 0; i < cpa->numpages; i++)
+ __flush_tlb_one_kernel(fix_addr(__cpa_addr(cpa, i)));
+}
+
+static void cpa_flush(struct cpa_data *data, int cache)
+{
+ struct cpa_data *cpa = data;
+ unsigned int i;
+
+ BUG_ON(irqs_disabled() && !early_boot_irqs_disabled);
+
+ if (cache && !static_cpu_has(X86_FEATURE_CLFLUSH)) {
+ cpa_flush_all(cache);
+ return;
+ }
+
+ if (cpa->numpages <= tlb_single_page_flush_ceiling)
+ on_each_cpu(__cpa_flush_tlb, cpa, 1);
+ else
+ flush_tlb_all();
+
+ if (!cache)
+ return;
+
+ mb();
+ for (i = 0; i < cpa->numpages; i++) {
+ unsigned long addr = __cpa_addr(cpa, i);
+ unsigned int level;
+
+ pte_t *pte = lookup_address(addr, &level);
+
+ /*
+ * Only flush present addresses:
+ */
+ if (pte && (pte_val(*pte) & _PAGE_PRESENT))
+ clflush_cache_range_opt((void *)fix_addr(addr), PAGE_SIZE);
+ }
+ mb();
+}
+
+static bool overlaps(unsigned long r1_start, unsigned long r1_end,
+ unsigned long r2_start, unsigned long r2_end)
+{
+ return (r1_start <= r2_end && r1_end >= r2_start) ||
+ (r2_start <= r1_end && r2_end >= r1_start);
+}
+
+#ifdef CONFIG_PCI_BIOS
+/*
+ * The BIOS area between 640k and 1Mb needs to be executable for PCI BIOS
+ * based config access (CONFIG_PCI_GOBIOS) support.
+ */
+#define BIOS_PFN PFN_DOWN(BIOS_BEGIN)
+#define BIOS_PFN_END PFN_DOWN(BIOS_END - 1)
+
+static pgprotval_t protect_pci_bios(unsigned long spfn, unsigned long epfn)
+{
+ if (pcibios_enabled && overlaps(spfn, epfn, BIOS_PFN, BIOS_PFN_END))
+ return _PAGE_NX;
+ return 0;
+}
+#else
+static pgprotval_t protect_pci_bios(unsigned long spfn, unsigned long epfn)
+{
+ return 0;
+}
+#endif
+
+/*
+ * The .rodata section needs to be read-only. Using the pfn catches all
+ * aliases. This also includes __ro_after_init, so do not enforce until
+ * kernel_set_to_readonly is true.
+ */
+static pgprotval_t protect_rodata(unsigned long spfn, unsigned long epfn)
+{
+ unsigned long epfn_ro, spfn_ro = PFN_DOWN(__pa_symbol(__start_rodata));
+
+ /*
+ * Note: __end_rodata is at page aligned and not inclusive, so
+ * subtract 1 to get the last enforced PFN in the rodata area.
+ */
+ epfn_ro = PFN_DOWN(__pa_symbol(__end_rodata)) - 1;
+
+ if (kernel_set_to_readonly && overlaps(spfn, epfn, spfn_ro, epfn_ro))
+ return _PAGE_RW;
+ return 0;
+}
+
+/*
+ * Protect kernel text against becoming non executable by forbidding
+ * _PAGE_NX. This protects only the high kernel mapping (_text -> _etext)
+ * out of which the kernel actually executes. Do not protect the low
+ * mapping.
+ *
+ * This does not cover __inittext since that is gone after boot.
+ */
+static pgprotval_t protect_kernel_text(unsigned long start, unsigned long end)
+{
+ unsigned long t_end = (unsigned long)_etext - 1;
+ unsigned long t_start = (unsigned long)_text;
+
+ if (overlaps(start, end, t_start, t_end))
+ return _PAGE_NX;
+ return 0;
+}
+
+#if defined(CONFIG_X86_64)
+/*
+ * Once the kernel maps the text as RO (kernel_set_to_readonly is set),
+ * kernel text mappings for the large page aligned text, rodata sections
+ * will be always read-only. For the kernel identity mappings covering the
+ * holes caused by this alignment can be anything that user asks.
+ *
+ * This will preserve the large page mappings for kernel text/data at no
+ * extra cost.
+ */
+static pgprotval_t protect_kernel_text_ro(unsigned long start,
+ unsigned long end)
+{
+ unsigned long t_end = (unsigned long)__end_rodata_hpage_align - 1;
+ unsigned long t_start = (unsigned long)_text;
+ unsigned int level;
+
+ if (!kernel_set_to_readonly || !overlaps(start, end, t_start, t_end))
+ return 0;
+ /*
+ * Don't enforce the !RW mapping for the kernel text mapping, if
+ * the current mapping is already using small page mapping. No
+ * need to work hard to preserve large page mappings in this case.
+ *
+ * This also fixes the Linux Xen paravirt guest boot failure caused
+ * by unexpected read-only mappings for kernel identity
+ * mappings. In this paravirt guest case, the kernel text mapping
+ * and the kernel identity mapping share the same page-table pages,
+ * so the protections for kernel text and identity mappings have to
+ * be the same.
+ */
+ if (lookup_address(start, &level) && (level != PG_LEVEL_4K))
+ return _PAGE_RW;
+ return 0;
+}
+#else
+static pgprotval_t protect_kernel_text_ro(unsigned long start,
+ unsigned long end)
+{
+ return 0;
+}
+#endif
+
+static inline bool conflicts(pgprot_t prot, pgprotval_t val)
+{
+ return (pgprot_val(prot) & ~val) != pgprot_val(prot);
+}
+
+static inline void check_conflict(int warnlvl, pgprot_t prot, pgprotval_t val,
+ unsigned long start, unsigned long end,
+ unsigned long pfn, const char *txt)
+{
+ static const char *lvltxt[] = {
+ [CPA_CONFLICT] = "conflict",
+ [CPA_PROTECT] = "protect",
+ [CPA_DETECT] = "detect",
+ };
+
+ if (warnlvl > cpa_warn_level || !conflicts(prot, val))
+ return;
+
+ pr_warn("CPA %8s %10s: 0x%016lx - 0x%016lx PFN %lx req %016llx prevent %016llx\n",
+ lvltxt[warnlvl], txt, start, end, pfn, (unsigned long long)pgprot_val(prot),
+ (unsigned long long)val);
+}
+
+/*
+ * Certain areas of memory on x86 require very specific protection flags,
+ * for example the BIOS area or kernel text. Callers don't always get this
+ * right (again, ioremap() on BIOS memory is not uncommon) so this function
+ * checks and fixes these known static required protection bits.
+ */
+static inline pgprot_t static_protections(pgprot_t prot, unsigned long start,
+ unsigned long pfn, unsigned long npg,
+ unsigned long lpsize, int warnlvl)
+{
+ pgprotval_t forbidden, res;
+ unsigned long end;
+
+ /*
+ * There is no point in checking RW/NX conflicts when the requested
+ * mapping is setting the page !PRESENT.
+ */
+ if (!(pgprot_val(prot) & _PAGE_PRESENT))
+ return prot;
+
+ /* Operate on the virtual address */
+ end = start + npg * PAGE_SIZE - 1;
+
+ res = protect_kernel_text(start, end);
+ check_conflict(warnlvl, prot, res, start, end, pfn, "Text NX");
+ forbidden = res;
+
+ /*
+ * Special case to preserve a large page. If the change spawns the
+ * full large page mapping then there is no point to split it
+ * up. Happens with ftrace and is going to be removed once ftrace
+ * switched to text_poke().
+ */
+ if (lpsize != (npg * PAGE_SIZE) || (start & (lpsize - 1))) {
+ res = protect_kernel_text_ro(start, end);
+ check_conflict(warnlvl, prot, res, start, end, pfn, "Text RO");
+ forbidden |= res;
+ }
+
+ /* Check the PFN directly */
+ res = protect_pci_bios(pfn, pfn + npg - 1);
+ check_conflict(warnlvl, prot, res, start, end, pfn, "PCIBIOS NX");
+ forbidden |= res;
+
+ res = protect_rodata(pfn, pfn + npg - 1);
+ check_conflict(warnlvl, prot, res, start, end, pfn, "Rodata RO");
+ forbidden |= res;
+
+ return __pgprot(pgprot_val(prot) & ~forbidden);
+}
+
+/*
+ * Lookup the page table entry for a virtual address in a specific pgd.
+ * Return a pointer to the entry and the level of the mapping.
+ */
+pte_t *lookup_address_in_pgd(pgd_t *pgd, unsigned long address,
+ unsigned int *level)
+{
+ p4d_t *p4d;
+ pud_t *pud;
+ pmd_t *pmd;
+
+ *level = PG_LEVEL_NONE;
+
+ if (pgd_none(*pgd))
+ return NULL;
+
+ p4d = p4d_offset(pgd, address);
+ if (p4d_none(*p4d))
+ return NULL;
+
+ *level = PG_LEVEL_512G;
+ if (p4d_large(*p4d) || !p4d_present(*p4d))
+ return (pte_t *)p4d;
+
+ pud = pud_offset(p4d, address);
+ if (pud_none(*pud))
+ return NULL;
+
+ *level = PG_LEVEL_1G;
+ if (pud_large(*pud) || !pud_present(*pud))
+ return (pte_t *)pud;
+
+ pmd = pmd_offset(pud, address);
+ if (pmd_none(*pmd))
+ return NULL;
+
+ *level = PG_LEVEL_2M;
+ if (pmd_large(*pmd) || !pmd_present(*pmd))
+ return (pte_t *)pmd;
+
+ *level = PG_LEVEL_4K;
+
+ return pte_offset_kernel(pmd, address);
+}
+
+/*
+ * Lookup the page table entry for a virtual address. Return a pointer
+ * to the entry and the level of the mapping.
+ *
+ * Note: We return pud and pmd either when the entry is marked large
+ * or when the present bit is not set. Otherwise we would return a
+ * pointer to a nonexisting mapping.
+ */
+pte_t *lookup_address(unsigned long address, unsigned int *level)
+{
+ return lookup_address_in_pgd(pgd_offset_k(address), address, level);
+}
+EXPORT_SYMBOL_GPL(lookup_address);
+
+static pte_t *_lookup_address_cpa(struct cpa_data *cpa, unsigned long address,
+ unsigned int *level)
+{
+ if (cpa->pgd)
+ return lookup_address_in_pgd(cpa->pgd + pgd_index(address),
+ address, level);
+
+ return lookup_address(address, level);
+}
+
+/*
+ * Lookup the PMD entry for a virtual address. Return a pointer to the entry
+ * or NULL if not present.
+ */
+pmd_t *lookup_pmd_address(unsigned long address)
+{
+ pgd_t *pgd;
+ p4d_t *p4d;
+ pud_t *pud;
+
+ pgd = pgd_offset_k(address);
+ if (pgd_none(*pgd))
+ return NULL;
+
+ p4d = p4d_offset(pgd, address);
+ if (p4d_none(*p4d) || p4d_large(*p4d) || !p4d_present(*p4d))
+ return NULL;
+
+ pud = pud_offset(p4d, address);
+ if (pud_none(*pud) || pud_large(*pud) || !pud_present(*pud))
+ return NULL;
+
+ return pmd_offset(pud, address);
+}
+
+/*
+ * This is necessary because __pa() does not work on some
+ * kinds of memory, like vmalloc() or the alloc_remap()
+ * areas on 32-bit NUMA systems. The percpu areas can
+ * end up in this kind of memory, for instance.
+ *
+ * This could be optimized, but it is only intended to be
+ * used at inititalization time, and keeping it
+ * unoptimized should increase the testing coverage for
+ * the more obscure platforms.
+ */
+phys_addr_t slow_virt_to_phys(void *__virt_addr)
+{
+ unsigned long virt_addr = (unsigned long)__virt_addr;
+ phys_addr_t phys_addr;
+ unsigned long offset;
+ enum pg_level level;
+ pte_t *pte;
+
+ pte = lookup_address(virt_addr, &level);
+ BUG_ON(!pte);
+
+ /*
+ * pXX_pfn() returns unsigned long, which must be cast to phys_addr_t
+ * before being left-shifted PAGE_SHIFT bits -- this trick is to
+ * make 32-PAE kernel work correctly.
+ */
+ switch (level) {
+ case PG_LEVEL_1G:
+ phys_addr = (phys_addr_t)pud_pfn(*(pud_t *)pte) << PAGE_SHIFT;
+ offset = virt_addr & ~PUD_PAGE_MASK;
+ break;
+ case PG_LEVEL_2M:
+ phys_addr = (phys_addr_t)pmd_pfn(*(pmd_t *)pte) << PAGE_SHIFT;
+ offset = virt_addr & ~PMD_PAGE_MASK;
+ break;
+ default:
+ phys_addr = (phys_addr_t)pte_pfn(*pte) << PAGE_SHIFT;
+ offset = virt_addr & ~PAGE_MASK;
+ }
+
+ return (phys_addr_t)(phys_addr | offset);
+}
+EXPORT_SYMBOL_GPL(slow_virt_to_phys);
+
+/*
+ * Set the new pmd in all the pgds we know about:
+ */
+static void __set_pmd_pte(pte_t *kpte, unsigned long address, pte_t pte)
+{
+ /* change init_mm */
+ set_pte_atomic(kpte, pte);
+#ifdef CONFIG_X86_32
+ if (!SHARED_KERNEL_PMD) {
+ struct page *page;
+
+ list_for_each_entry(page, &pgd_list, lru) {
+ pgd_t *pgd;
+ p4d_t *p4d;
+ pud_t *pud;
+ pmd_t *pmd;
+
+ pgd = (pgd_t *)page_address(page) + pgd_index(address);
+ p4d = p4d_offset(pgd, address);
+ pud = pud_offset(p4d, address);
+ pmd = pmd_offset(pud, address);
+ set_pte_atomic((pte_t *)pmd, pte);
+ }
+ }
+#endif
+}
+
+static pgprot_t pgprot_clear_protnone_bits(pgprot_t prot)
+{
+ /*
+ * _PAGE_GLOBAL means "global page" for present PTEs.
+ * But, it is also used to indicate _PAGE_PROTNONE
+ * for non-present PTEs.
+ *
+ * This ensures that a _PAGE_GLOBAL PTE going from
+ * present to non-present is not confused as
+ * _PAGE_PROTNONE.
+ */
+ if (!(pgprot_val(prot) & _PAGE_PRESENT))
+ pgprot_val(prot) &= ~_PAGE_GLOBAL;
+
+ return prot;
+}
+
+static int __should_split_large_page(pte_t *kpte, unsigned long address,
+ struct cpa_data *cpa)
+{
+ unsigned long numpages, pmask, psize, lpaddr, pfn, old_pfn;
+ pgprot_t old_prot, new_prot, req_prot, chk_prot;
+ pte_t new_pte, *tmp;
+ enum pg_level level;
+
+ /*
+ * Check for races, another CPU might have split this page
+ * up already:
+ */
+ tmp = _lookup_address_cpa(cpa, address, &level);
+ if (tmp != kpte)
+ return 1;
+
+ switch (level) {
+ case PG_LEVEL_2M:
+ old_prot = pmd_pgprot(*(pmd_t *)kpte);
+ old_pfn = pmd_pfn(*(pmd_t *)kpte);
+ cpa_inc_2m_checked();
+ break;
+ case PG_LEVEL_1G:
+ old_prot = pud_pgprot(*(pud_t *)kpte);
+ old_pfn = pud_pfn(*(pud_t *)kpte);
+ cpa_inc_1g_checked();
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ psize = page_level_size(level);
+ pmask = page_level_mask(level);
+
+ /*
+ * Calculate the number of pages, which fit into this large
+ * page starting at address:
+ */
+ lpaddr = (address + psize) & pmask;
+ numpages = (lpaddr - address) >> PAGE_SHIFT;
+ if (numpages < cpa->numpages)
+ cpa->numpages = numpages;
+
+ /*
+ * We are safe now. Check whether the new pgprot is the same:
+ * Convert protection attributes to 4k-format, as cpa->mask* are set
+ * up accordingly.
+ */
+
+ /* Clear PSE (aka _PAGE_PAT) and move PAT bit to correct position */
+ req_prot = pgprot_large_2_4k(old_prot);
+
+ pgprot_val(req_prot) &= ~pgprot_val(cpa->mask_clr);
+ pgprot_val(req_prot) |= pgprot_val(cpa->mask_set);
+
+ /*
+ * req_prot is in format of 4k pages. It must be converted to large
+ * page format: the caching mode includes the PAT bit located at
+ * different bit positions in the two formats.
+ */
+ req_prot = pgprot_4k_2_large(req_prot);
+ req_prot = pgprot_clear_protnone_bits(req_prot);
+ if (pgprot_val(req_prot) & _PAGE_PRESENT)
+ pgprot_val(req_prot) |= _PAGE_PSE;
+
+ /*
+ * old_pfn points to the large page base pfn. So we need to add the
+ * offset of the virtual address:
+ */
+ pfn = old_pfn + ((address & (psize - 1)) >> PAGE_SHIFT);
+ cpa->pfn = pfn;
+
+ /*
+ * Calculate the large page base address and the number of 4K pages
+ * in the large page
+ */
+ lpaddr = address & pmask;
+ numpages = psize >> PAGE_SHIFT;
+
+ /*
+ * Sanity check that the existing mapping is correct versus the static
+ * protections. static_protections() guards against !PRESENT, so no
+ * extra conditional required here.
+ */
+ chk_prot = static_protections(old_prot, lpaddr, old_pfn, numpages,
+ psize, CPA_CONFLICT);
+
+ if (WARN_ON_ONCE(pgprot_val(chk_prot) != pgprot_val(old_prot))) {
+ /*
+ * Split the large page and tell the split code to
+ * enforce static protections.
+ */
+ cpa->force_static_prot = 1;
+ return 1;
+ }
+
+ /*
+ * Optimization: If the requested pgprot is the same as the current
+ * pgprot, then the large page can be preserved and no updates are
+ * required independent of alignment and length of the requested
+ * range. The above already established that the current pgprot is
+ * correct, which in consequence makes the requested pgprot correct
+ * as well if it is the same. The static protection scan below will
+ * not come to a different conclusion.
+ */
+ if (pgprot_val(req_prot) == pgprot_val(old_prot)) {
+ cpa_inc_lp_sameprot(level);
+ return 0;
+ }
+
+ /*
+ * If the requested range does not cover the full page, split it up
+ */
+ if (address != lpaddr || cpa->numpages != numpages)
+ return 1;
+
+ /*
+ * Check whether the requested pgprot is conflicting with a static
+ * protection requirement in the large page.
+ */
+ new_prot = static_protections(req_prot, lpaddr, old_pfn, numpages,
+ psize, CPA_DETECT);
+
+ /*
+ * If there is a conflict, split the large page.
+ *
+ * There used to be a 4k wise evaluation trying really hard to
+ * preserve the large pages, but experimentation has shown, that this
+ * does not help at all. There might be corner cases which would
+ * preserve one large page occasionally, but it's really not worth the
+ * extra code and cycles for the common case.
+ */
+ if (pgprot_val(req_prot) != pgprot_val(new_prot))
+ return 1;
+
+ /* All checks passed. Update the large page mapping. */
+ new_pte = pfn_pte(old_pfn, new_prot);
+ __set_pmd_pte(kpte, address, new_pte);
+ cpa->flags |= CPA_FLUSHTLB;
+ cpa_inc_lp_preserved(level);
+ return 0;
+}
+
+static int should_split_large_page(pte_t *kpte, unsigned long address,
+ struct cpa_data *cpa)
+{
+ int do_split;
+
+ if (cpa->force_split)
+ return 1;
+
+ spin_lock(&pgd_lock);
+ do_split = __should_split_large_page(kpte, address, cpa);
+ spin_unlock(&pgd_lock);
+
+ return do_split;
+}
+
+static void split_set_pte(struct cpa_data *cpa, pte_t *pte, unsigned long pfn,
+ pgprot_t ref_prot, unsigned long address,
+ unsigned long size)
+{
+ unsigned int npg = PFN_DOWN(size);
+ pgprot_t prot;
+
+ /*
+ * If should_split_large_page() discovered an inconsistent mapping,
+ * remove the invalid protection in the split mapping.
+ */
+ if (!cpa->force_static_prot)
+ goto set;
+
+ /* Hand in lpsize = 0 to enforce the protection mechanism */
+ prot = static_protections(ref_prot, address, pfn, npg, 0, CPA_PROTECT);
+
+ if (pgprot_val(prot) == pgprot_val(ref_prot))
+ goto set;
+
+ /*
+ * If this is splitting a PMD, fix it up. PUD splits cannot be
+ * fixed trivially as that would require to rescan the newly
+ * installed PMD mappings after returning from split_large_page()
+ * so an eventual further split can allocate the necessary PTE
+ * pages. Warn for now and revisit it in case this actually
+ * happens.
+ */
+ if (size == PAGE_SIZE)
+ ref_prot = prot;
+ else
+ pr_warn_once("CPA: Cannot fixup static protections for PUD split\n");
+set:
+ set_pte(pte, pfn_pte(pfn, ref_prot));
+}
+
+static int
+__split_large_page(struct cpa_data *cpa, pte_t *kpte, unsigned long address,
+ struct page *base)
+{
+ unsigned long lpaddr, lpinc, ref_pfn, pfn, pfninc = 1;
+ pte_t *pbase = (pte_t *)page_address(base);
+ unsigned int i, level;
+ pgprot_t ref_prot;
+ pte_t *tmp;
+
+ spin_lock(&pgd_lock);
+ /*
+ * Check for races, another CPU might have split this page
+ * up for us already:
+ */
+ tmp = _lookup_address_cpa(cpa, address, &level);
+ if (tmp != kpte) {
+ spin_unlock(&pgd_lock);
+ return 1;
+ }
+
+ paravirt_alloc_pte(&init_mm, page_to_pfn(base));
+
+ switch (level) {
+ case PG_LEVEL_2M:
+ ref_prot = pmd_pgprot(*(pmd_t *)kpte);
+ /*
+ * Clear PSE (aka _PAGE_PAT) and move
+ * PAT bit to correct position.
+ */
+ ref_prot = pgprot_large_2_4k(ref_prot);
+ ref_pfn = pmd_pfn(*(pmd_t *)kpte);
+ lpaddr = address & PMD_MASK;
+ lpinc = PAGE_SIZE;
+ break;
+
+ case PG_LEVEL_1G:
+ ref_prot = pud_pgprot(*(pud_t *)kpte);
+ ref_pfn = pud_pfn(*(pud_t *)kpte);
+ pfninc = PMD_PAGE_SIZE >> PAGE_SHIFT;
+ lpaddr = address & PUD_MASK;
+ lpinc = PMD_SIZE;
+ /*
+ * Clear the PSE flags if the PRESENT flag is not set
+ * otherwise pmd_present/pmd_huge will return true
+ * even on a non present pmd.
+ */
+ if (!(pgprot_val(ref_prot) & _PAGE_PRESENT))
+ pgprot_val(ref_prot) &= ~_PAGE_PSE;
+ break;
+
+ default:
+ spin_unlock(&pgd_lock);
+ return 1;
+ }
+
+ ref_prot = pgprot_clear_protnone_bits(ref_prot);
+
+ /*
+ * Get the target pfn from the original entry:
+ */
+ pfn = ref_pfn;
+ for (i = 0; i < PTRS_PER_PTE; i++, pfn += pfninc, lpaddr += lpinc)
+ split_set_pte(cpa, pbase + i, pfn, ref_prot, lpaddr, lpinc);
+
+ if (virt_addr_valid(address)) {
+ unsigned long pfn = PFN_DOWN(__pa(address));
+
+ if (pfn_range_is_mapped(pfn, pfn + 1))
+ split_page_count(level);
+ }
+
+ /*
+ * Install the new, split up pagetable.
+ *
+ * We use the standard kernel pagetable protections for the new
+ * pagetable protections, the actual ptes set above control the
+ * primary protection behavior:
+ */
+ __set_pmd_pte(kpte, address, mk_pte(base, __pgprot(_KERNPG_TABLE)));
+
+ /*
+ * Do a global flush tlb after splitting the large page
+ * and before we do the actual change page attribute in the PTE.
+ *
+ * Without this, we violate the TLB application note, that says:
+ * "The TLBs may contain both ordinary and large-page
+ * translations for a 4-KByte range of linear addresses. This
+ * may occur if software modifies the paging structures so that
+ * the page size used for the address range changes. If the two
+ * translations differ with respect to page frame or attributes
+ * (e.g., permissions), processor behavior is undefined and may
+ * be implementation-specific."
+ *
+ * We do this global tlb flush inside the cpa_lock, so that we
+ * don't allow any other cpu, with stale tlb entries change the
+ * page attribute in parallel, that also falls into the
+ * just split large page entry.
+ */
+ flush_tlb_all();
+ spin_unlock(&pgd_lock);
+
+ return 0;
+}
+
+static int split_large_page(struct cpa_data *cpa, pte_t *kpte,
+ unsigned long address)
+{
+ struct page *base;
+
+ if (!debug_pagealloc_enabled())
+ spin_unlock(&cpa_lock);
+ base = alloc_pages(GFP_KERNEL, 0);
+ if (!debug_pagealloc_enabled())
+ spin_lock(&cpa_lock);
+ if (!base)
+ return -ENOMEM;
+
+ if (__split_large_page(cpa, kpte, address, base))
+ __free_page(base);
+
+ return 0;
+}
+
+static bool try_to_free_pte_page(pte_t *pte)
+{
+ int i;
+
+ for (i = 0; i < PTRS_PER_PTE; i++)
+ if (!pte_none(pte[i]))
+ return false;
+
+ free_page((unsigned long)pte);
+ return true;
+}
+
+static bool try_to_free_pmd_page(pmd_t *pmd)
+{
+ int i;
+
+ for (i = 0; i < PTRS_PER_PMD; i++)
+ if (!pmd_none(pmd[i]))
+ return false;
+
+ free_page((unsigned long)pmd);
+ return true;
+}
+
+static bool unmap_pte_range(pmd_t *pmd, unsigned long start, unsigned long end)
+{
+ pte_t *pte = pte_offset_kernel(pmd, start);
+
+ while (start < end) {
+ set_pte(pte, __pte(0));
+
+ start += PAGE_SIZE;
+ pte++;
+ }
+
+ if (try_to_free_pte_page((pte_t *)pmd_page_vaddr(*pmd))) {
+ pmd_clear(pmd);
+ return true;
+ }
+ return false;
+}
+
+static void __unmap_pmd_range(pud_t *pud, pmd_t *pmd,
+ unsigned long start, unsigned long end)
+{
+ if (unmap_pte_range(pmd, start, end))
+ if (try_to_free_pmd_page((pmd_t *)pud_page_vaddr(*pud)))
+ pud_clear(pud);
+}
+
+static void unmap_pmd_range(pud_t *pud, unsigned long start, unsigned long end)
+{
+ pmd_t *pmd = pmd_offset(pud, start);
+
+ /*
+ * Not on a 2MB page boundary?
+ */
+ if (start & (PMD_SIZE - 1)) {
+ unsigned long next_page = (start + PMD_SIZE) & PMD_MASK;
+ unsigned long pre_end = min_t(unsigned long, end, next_page);
+
+ __unmap_pmd_range(pud, pmd, start, pre_end);
+
+ start = pre_end;
+ pmd++;
+ }
+
+ /*
+ * Try to unmap in 2M chunks.
+ */
+ while (end - start >= PMD_SIZE) {
+ if (pmd_large(*pmd))
+ pmd_clear(pmd);
+ else
+ __unmap_pmd_range(pud, pmd, start, start + PMD_SIZE);
+
+ start += PMD_SIZE;
+ pmd++;
+ }
+
+ /*
+ * 4K leftovers?
+ */
+ if (start < end)
+ return __unmap_pmd_range(pud, pmd, start, end);
+
+ /*
+ * Try again to free the PMD page if haven't succeeded above.
+ */
+ if (!pud_none(*pud))
+ if (try_to_free_pmd_page((pmd_t *)pud_page_vaddr(*pud)))
+ pud_clear(pud);
+}
+
+static void unmap_pud_range(p4d_t *p4d, unsigned long start, unsigned long end)
+{
+ pud_t *pud = pud_offset(p4d, start);
+
+ /*
+ * Not on a GB page boundary?
+ */
+ if (start & (PUD_SIZE - 1)) {
+ unsigned long next_page = (start + PUD_SIZE) & PUD_MASK;
+ unsigned long pre_end = min_t(unsigned long, end, next_page);
+
+ unmap_pmd_range(pud, start, pre_end);
+
+ start = pre_end;
+ pud++;
+ }
+
+ /*
+ * Try to unmap in 1G chunks?
+ */
+ while (end - start >= PUD_SIZE) {
+
+ if (pud_large(*pud))
+ pud_clear(pud);
+ else
+ unmap_pmd_range(pud, start, start + PUD_SIZE);
+
+ start += PUD_SIZE;
+ pud++;
+ }
+
+ /*
+ * 2M leftovers?
+ */
+ if (start < end)
+ unmap_pmd_range(pud, start, end);
+
+ /*
+ * No need to try to free the PUD page because we'll free it in
+ * populate_pgd's error path
+ */
+}
+
+static int alloc_pte_page(pmd_t *pmd)
+{
+ pte_t *pte = (pte_t *)get_zeroed_page(GFP_KERNEL);
+ if (!pte)
+ return -1;
+
+ set_pmd(pmd, __pmd(__pa(pte) | _KERNPG_TABLE));
+ return 0;
+}
+
+static int alloc_pmd_page(pud_t *pud)
+{
+ pmd_t *pmd = (pmd_t *)get_zeroed_page(GFP_KERNEL);
+ if (!pmd)
+ return -1;
+
+ set_pud(pud, __pud(__pa(pmd) | _KERNPG_TABLE));
+ return 0;
+}
+
+static void populate_pte(struct cpa_data *cpa,
+ unsigned long start, unsigned long end,
+ unsigned num_pages, pmd_t *pmd, pgprot_t pgprot)
+{
+ pte_t *pte;
+
+ pte = pte_offset_kernel(pmd, start);
+
+ pgprot = pgprot_clear_protnone_bits(pgprot);
+
+ while (num_pages-- && start < end) {
+ set_pte(pte, pfn_pte(cpa->pfn, pgprot));
+
+ start += PAGE_SIZE;
+ cpa->pfn++;
+ pte++;
+ }
+}
+
+static long populate_pmd(struct cpa_data *cpa,
+ unsigned long start, unsigned long end,
+ unsigned num_pages, pud_t *pud, pgprot_t pgprot)
+{
+ long cur_pages = 0;
+ pmd_t *pmd;
+ pgprot_t pmd_pgprot;
+
+ /*
+ * Not on a 2M boundary?
+ */
+ if (start & (PMD_SIZE - 1)) {
+ unsigned long pre_end = start + (num_pages << PAGE_SHIFT);
+ unsigned long next_page = (start + PMD_SIZE) & PMD_MASK;
+
+ pre_end = min_t(unsigned long, pre_end, next_page);
+ cur_pages = (pre_end - start) >> PAGE_SHIFT;
+ cur_pages = min_t(unsigned int, num_pages, cur_pages);
+
+ /*
+ * Need a PTE page?
+ */
+ pmd = pmd_offset(pud, start);
+ if (pmd_none(*pmd))
+ if (alloc_pte_page(pmd))
+ return -1;
+
+ populate_pte(cpa, start, pre_end, cur_pages, pmd, pgprot);
+
+ start = pre_end;
+ }
+
+ /*
+ * We mapped them all?
+ */
+ if (num_pages == cur_pages)
+ return cur_pages;
+
+ pmd_pgprot = pgprot_4k_2_large(pgprot);
+
+ while (end - start >= PMD_SIZE) {
+
+ /*
+ * We cannot use a 1G page so allocate a PMD page if needed.
+ */
+ if (pud_none(*pud))
+ if (alloc_pmd_page(pud))
+ return -1;
+
+ pmd = pmd_offset(pud, start);
+
+ set_pmd(pmd, pmd_mkhuge(pfn_pmd(cpa->pfn,
+ canon_pgprot(pmd_pgprot))));
+
+ start += PMD_SIZE;
+ cpa->pfn += PMD_SIZE >> PAGE_SHIFT;
+ cur_pages += PMD_SIZE >> PAGE_SHIFT;
+ }
+
+ /*
+ * Map trailing 4K pages.
+ */
+ if (start < end) {
+ pmd = pmd_offset(pud, start);
+ if (pmd_none(*pmd))
+ if (alloc_pte_page(pmd))
+ return -1;
+
+ populate_pte(cpa, start, end, num_pages - cur_pages,
+ pmd, pgprot);
+ }
+ return num_pages;
+}
+
+static int populate_pud(struct cpa_data *cpa, unsigned long start, p4d_t *p4d,
+ pgprot_t pgprot)
+{
+ pud_t *pud;
+ unsigned long end;
+ long cur_pages = 0;
+ pgprot_t pud_pgprot;
+
+ end = start + (cpa->numpages << PAGE_SHIFT);
+
+ /*
+ * Not on a Gb page boundary? => map everything up to it with
+ * smaller pages.
+ */
+ if (start & (PUD_SIZE - 1)) {
+ unsigned long pre_end;
+ unsigned long next_page = (start + PUD_SIZE) & PUD_MASK;
+
+ pre_end = min_t(unsigned long, end, next_page);
+ cur_pages = (pre_end - start) >> PAGE_SHIFT;
+ cur_pages = min_t(int, (int)cpa->numpages, cur_pages);
+
+ pud = pud_offset(p4d, start);
+
+ /*
+ * Need a PMD page?
+ */
+ if (pud_none(*pud))
+ if (alloc_pmd_page(pud))
+ return -1;
+
+ cur_pages = populate_pmd(cpa, start, pre_end, cur_pages,
+ pud, pgprot);
+ if (cur_pages < 0)
+ return cur_pages;
+
+ start = pre_end;
+ }
+
+ /* We mapped them all? */
+ if (cpa->numpages == cur_pages)
+ return cur_pages;
+
+ pud = pud_offset(p4d, start);
+ pud_pgprot = pgprot_4k_2_large(pgprot);
+
+ /*
+ * Map everything starting from the Gb boundary, possibly with 1G pages
+ */
+ while (boot_cpu_has(X86_FEATURE_GBPAGES) && end - start >= PUD_SIZE) {
+ set_pud(pud, pud_mkhuge(pfn_pud(cpa->pfn,
+ canon_pgprot(pud_pgprot))));
+
+ start += PUD_SIZE;
+ cpa->pfn += PUD_SIZE >> PAGE_SHIFT;
+ cur_pages += PUD_SIZE >> PAGE_SHIFT;
+ pud++;
+ }
+
+ /* Map trailing leftover */
+ if (start < end) {
+ long tmp;
+
+ pud = pud_offset(p4d, start);
+ if (pud_none(*pud))
+ if (alloc_pmd_page(pud))
+ return -1;
+
+ tmp = populate_pmd(cpa, start, end, cpa->numpages - cur_pages,
+ pud, pgprot);
+ if (tmp < 0)
+ return cur_pages;
+
+ cur_pages += tmp;
+ }
+ return cur_pages;
+}
+
+/*
+ * Restrictions for kernel page table do not necessarily apply when mapping in
+ * an alternate PGD.
+ */
+static int populate_pgd(struct cpa_data *cpa, unsigned long addr)
+{
+ pgprot_t pgprot = __pgprot(_KERNPG_TABLE);
+ pud_t *pud = NULL; /* shut up gcc */
+ p4d_t *p4d;
+ pgd_t *pgd_entry;
+ long ret;
+
+ pgd_entry = cpa->pgd + pgd_index(addr);
+
+ if (pgd_none(*pgd_entry)) {
+ p4d = (p4d_t *)get_zeroed_page(GFP_KERNEL);
+ if (!p4d)
+ return -1;
+
+ set_pgd(pgd_entry, __pgd(__pa(p4d) | _KERNPG_TABLE));
+ }
+
+ /*
+ * Allocate a PUD page and hand it down for mapping.
+ */
+ p4d = p4d_offset(pgd_entry, addr);
+ if (p4d_none(*p4d)) {
+ pud = (pud_t *)get_zeroed_page(GFP_KERNEL);
+ if (!pud)
+ return -1;
+
+ set_p4d(p4d, __p4d(__pa(pud) | _KERNPG_TABLE));
+ }
+
+ pgprot_val(pgprot) &= ~pgprot_val(cpa->mask_clr);
+ pgprot_val(pgprot) |= pgprot_val(cpa->mask_set);
+
+ ret = populate_pud(cpa, addr, p4d, pgprot);
+ if (ret < 0) {
+ /*
+ * Leave the PUD page in place in case some other CPU or thread
+ * already found it, but remove any useless entries we just
+ * added to it.
+ */
+ unmap_pud_range(p4d, addr,
+ addr + (cpa->numpages << PAGE_SHIFT));
+ return ret;
+ }
+
+ cpa->numpages = ret;
+ return 0;
+}
+
+static int __cpa_process_fault(struct cpa_data *cpa, unsigned long vaddr,
+ int primary)
+{
+ if (cpa->pgd) {
+ /*
+ * Right now, we only execute this code path when mapping
+ * the EFI virtual memory map regions, no other users
+ * provide a ->pgd value. This may change in the future.
+ */
+ return populate_pgd(cpa, vaddr);
+ }
+
+ /*
+ * Ignore all non primary paths.
+ */
+ if (!primary) {
+ cpa->numpages = 1;
+ return 0;
+ }
+
+ /*
+ * Ignore the NULL PTE for kernel identity mapping, as it is expected
+ * to have holes.
+ * Also set numpages to '1' indicating that we processed cpa req for
+ * one virtual address page and its pfn. TBD: numpages can be set based
+ * on the initial value and the level returned by lookup_address().
+ */
+ if (within(vaddr, PAGE_OFFSET,
+ PAGE_OFFSET + (max_pfn_mapped << PAGE_SHIFT))) {
+ cpa->numpages = 1;
+ cpa->pfn = __pa(vaddr) >> PAGE_SHIFT;
+ return 0;
+
+ } else if (__cpa_pfn_in_highmap(cpa->pfn)) {
+ /* Faults in the highmap are OK, so do not warn: */
+ return -EFAULT;
+ } else {
+ WARN(1, KERN_WARNING "CPA: called for zero pte. "
+ "vaddr = %lx cpa->vaddr = %lx\n", vaddr,
+ *cpa->vaddr);
+
+ return -EFAULT;
+ }
+}
+
+static int __change_page_attr(struct cpa_data *cpa, int primary)
+{
+ unsigned long address;
+ int do_split, err;
+ unsigned int level;
+ pte_t *kpte, old_pte;
+
+ address = __cpa_addr(cpa, cpa->curpage);
+repeat:
+ kpte = _lookup_address_cpa(cpa, address, &level);
+ if (!kpte)
+ return __cpa_process_fault(cpa, address, primary);
+
+ old_pte = *kpte;
+ if (pte_none(old_pte))
+ return __cpa_process_fault(cpa, address, primary);
+
+ if (level == PG_LEVEL_4K) {
+ pte_t new_pte;
+ pgprot_t new_prot = pte_pgprot(old_pte);
+ unsigned long pfn = pte_pfn(old_pte);
+
+ pgprot_val(new_prot) &= ~pgprot_val(cpa->mask_clr);
+ pgprot_val(new_prot) |= pgprot_val(cpa->mask_set);
+
+ cpa_inc_4k_install();
+ /* Hand in lpsize = 0 to enforce the protection mechanism */
+ new_prot = static_protections(new_prot, address, pfn, 1, 0,
+ CPA_PROTECT);
+
+ new_prot = pgprot_clear_protnone_bits(new_prot);
+
+ /*
+ * We need to keep the pfn from the existing PTE,
+ * after all we're only going to change it's attributes
+ * not the memory it points to
+ */
+ new_pte = pfn_pte(pfn, new_prot);
+ cpa->pfn = pfn;
+ /*
+ * Do we really change anything ?
+ */
+ if (pte_val(old_pte) != pte_val(new_pte)) {
+ set_pte_atomic(kpte, new_pte);
+ cpa->flags |= CPA_FLUSHTLB;
+ }
+ cpa->numpages = 1;
+ return 0;
+ }
+
+ /*
+ * Check, whether we can keep the large page intact
+ * and just change the pte:
+ */
+ do_split = should_split_large_page(kpte, address, cpa);
+ /*
+ * When the range fits into the existing large page,
+ * return. cp->numpages and cpa->tlbflush have been updated in
+ * try_large_page:
+ */
+ if (do_split <= 0)
+ return do_split;
+
+ /*
+ * We have to split the large page:
+ */
+ err = split_large_page(cpa, kpte, address);
+ if (!err)
+ goto repeat;
+
+ return err;
+}
+
+static int __change_page_attr_set_clr(struct cpa_data *cpa, int checkalias);
+
+static int cpa_process_alias(struct cpa_data *cpa)
+{
+ struct cpa_data alias_cpa;
+ unsigned long laddr = (unsigned long)__va(cpa->pfn << PAGE_SHIFT);
+ unsigned long vaddr;
+ int ret;
+
+ if (!pfn_range_is_mapped(cpa->pfn, cpa->pfn + 1))
+ return 0;
+
+ /*
+ * No need to redo, when the primary call touched the direct
+ * mapping already:
+ */
+ vaddr = __cpa_addr(cpa, cpa->curpage);
+ if (!(within(vaddr, PAGE_OFFSET,
+ PAGE_OFFSET + (max_pfn_mapped << PAGE_SHIFT)))) {
+
+ alias_cpa = *cpa;
+ alias_cpa.vaddr = &laddr;
+ alias_cpa.flags &= ~(CPA_PAGES_ARRAY | CPA_ARRAY);
+ alias_cpa.curpage = 0;
+
+ ret = __change_page_attr_set_clr(&alias_cpa, 0);
+ if (ret)
+ return ret;
+ }
+
+#ifdef CONFIG_X86_64
+ /*
+ * If the primary call didn't touch the high mapping already
+ * and the physical address is inside the kernel map, we need
+ * to touch the high mapped kernel as well:
+ */
+ if (!within(vaddr, (unsigned long)_text, _brk_end) &&
+ __cpa_pfn_in_highmap(cpa->pfn)) {
+ unsigned long temp_cpa_vaddr = (cpa->pfn << PAGE_SHIFT) +
+ __START_KERNEL_map - phys_base;
+ alias_cpa = *cpa;
+ alias_cpa.vaddr = &temp_cpa_vaddr;
+ alias_cpa.flags &= ~(CPA_PAGES_ARRAY | CPA_ARRAY);
+ alias_cpa.curpage = 0;
+
+ /*
+ * The high mapping range is imprecise, so ignore the
+ * return value.
+ */
+ __change_page_attr_set_clr(&alias_cpa, 0);
+ }
+#endif
+
+ return 0;
+}
+
+static int __change_page_attr_set_clr(struct cpa_data *cpa, int checkalias)
+{
+ unsigned long numpages = cpa->numpages;
+ unsigned long rempages = numpages;
+ int ret = 0;
+
+ while (rempages) {
+ /*
+ * Store the remaining nr of pages for the large page
+ * preservation check.
+ */
+ cpa->numpages = rempages;
+ /* for array changes, we can't use large page */
+ if (cpa->flags & (CPA_ARRAY | CPA_PAGES_ARRAY))
+ cpa->numpages = 1;
+
+ if (!debug_pagealloc_enabled())
+ spin_lock(&cpa_lock);
+ ret = __change_page_attr(cpa, checkalias);
+ if (!debug_pagealloc_enabled())
+ spin_unlock(&cpa_lock);
+ if (ret)
+ goto out;
+
+ if (checkalias) {
+ ret = cpa_process_alias(cpa);
+ if (ret)
+ goto out;
+ }
+
+ /*
+ * Adjust the number of pages with the result of the
+ * CPA operation. Either a large page has been
+ * preserved or a single page update happened.
+ */
+ BUG_ON(cpa->numpages > rempages || !cpa->numpages);
+ rempages -= cpa->numpages;
+ cpa->curpage += cpa->numpages;
+ }
+
+out:
+ /* Restore the original numpages */
+ cpa->numpages = numpages;
+ return ret;
+}
+
+static int change_page_attr_set_clr(unsigned long *addr, int numpages,
+ pgprot_t mask_set, pgprot_t mask_clr,
+ int force_split, int in_flag,
+ struct page **pages)
+{
+ struct cpa_data cpa;
+ int ret, cache, checkalias;
+
+ memset(&cpa, 0, sizeof(cpa));
+
+ /*
+ * Check, if we are requested to set a not supported
+ * feature. Clearing non-supported features is OK.
+ */
+ mask_set = canon_pgprot(mask_set);
+
+ if (!pgprot_val(mask_set) && !pgprot_val(mask_clr) && !force_split)
+ return 0;
+
+ /* Ensure we are PAGE_SIZE aligned */
+ if (in_flag & CPA_ARRAY) {
+ int i;
+ for (i = 0; i < numpages; i++) {
+ if (addr[i] & ~PAGE_MASK) {
+ addr[i] &= PAGE_MASK;
+ WARN_ON_ONCE(1);
+ }
+ }
+ } else if (!(in_flag & CPA_PAGES_ARRAY)) {
+ /*
+ * in_flag of CPA_PAGES_ARRAY implies it is aligned.
+ * No need to check in that case
+ */
+ if (*addr & ~PAGE_MASK) {
+ *addr &= PAGE_MASK;
+ /*
+ * People should not be passing in unaligned addresses:
+ */
+ WARN_ON_ONCE(1);
+ }
+ }
+
+ /* Must avoid aliasing mappings in the highmem code */
+ kmap_flush_unused();
+
+ vm_unmap_aliases();
+
+ cpa.vaddr = addr;
+ cpa.pages = pages;
+ cpa.numpages = numpages;
+ cpa.mask_set = mask_set;
+ cpa.mask_clr = mask_clr;
+ cpa.flags = 0;
+ cpa.curpage = 0;
+ cpa.force_split = force_split;
+
+ if (in_flag & (CPA_ARRAY | CPA_PAGES_ARRAY))
+ cpa.flags |= in_flag;
+
+ /* No alias checking for _NX bit modifications */
+ checkalias = (pgprot_val(mask_set) | pgprot_val(mask_clr)) != _PAGE_NX;
+ /* Has caller explicitly disabled alias checking? */
+ if (in_flag & CPA_NO_CHECK_ALIAS)
+ checkalias = 0;
+
+ ret = __change_page_attr_set_clr(&cpa, checkalias);
+
+ /*
+ * Check whether we really changed something:
+ */
+ if (!(cpa.flags & CPA_FLUSHTLB))
+ goto out;
+
+ /*
+ * No need to flush, when we did not set any of the caching
+ * attributes:
+ */
+ cache = !!pgprot2cachemode(mask_set);
+
+ /*
+ * On error; flush everything to be sure.
+ */
+ if (ret) {
+ cpa_flush_all(cache);
+ goto out;
+ }
+
+ cpa_flush(&cpa, cache);
+out:
+ return ret;
+}
+
+static inline int change_page_attr_set(unsigned long *addr, int numpages,
+ pgprot_t mask, int array)
+{
+ return change_page_attr_set_clr(addr, numpages, mask, __pgprot(0), 0,
+ (array ? CPA_ARRAY : 0), NULL);
+}
+
+static inline int change_page_attr_clear(unsigned long *addr, int numpages,
+ pgprot_t mask, int array)
+{
+ return change_page_attr_set_clr(addr, numpages, __pgprot(0), mask, 0,
+ (array ? CPA_ARRAY : 0), NULL);
+}
+
+static inline int cpa_set_pages_array(struct page **pages, int numpages,
+ pgprot_t mask)
+{
+ return change_page_attr_set_clr(NULL, numpages, mask, __pgprot(0), 0,
+ CPA_PAGES_ARRAY, pages);
+}
+
+static inline int cpa_clear_pages_array(struct page **pages, int numpages,
+ pgprot_t mask)
+{
+ return change_page_attr_set_clr(NULL, numpages, __pgprot(0), mask, 0,
+ CPA_PAGES_ARRAY, pages);
+}
+
+int _set_memory_uc(unsigned long addr, int numpages)
+{
+ /*
+ * for now UC MINUS. see comments in ioremap()
+ * If you really need strong UC use ioremap_uc(), but note
+ * that you cannot override IO areas with set_memory_*() as
+ * these helpers cannot work with IO memory.
+ */
+ return change_page_attr_set(&addr, numpages,
+ cachemode2pgprot(_PAGE_CACHE_MODE_UC_MINUS),
+ 0);
+}
+
+int set_memory_uc(unsigned long addr, int numpages)
+{
+ int ret;
+
+ /*
+ * for now UC MINUS. see comments in ioremap()
+ */
+ ret = reserve_memtype(__pa(addr), __pa(addr) + numpages * PAGE_SIZE,
+ _PAGE_CACHE_MODE_UC_MINUS, NULL);
+ if (ret)
+ goto out_err;
+
+ ret = _set_memory_uc(addr, numpages);
+ if (ret)
+ goto out_free;
+
+ return 0;
+
+out_free:
+ free_memtype(__pa(addr), __pa(addr) + numpages * PAGE_SIZE);
+out_err:
+ return ret;
+}
+EXPORT_SYMBOL(set_memory_uc);
+
+int _set_memory_wc(unsigned long addr, int numpages)
+{
+ int ret;
+
+ ret = change_page_attr_set(&addr, numpages,
+ cachemode2pgprot(_PAGE_CACHE_MODE_UC_MINUS),
+ 0);
+ if (!ret) {
+ ret = change_page_attr_set_clr(&addr, numpages,
+ cachemode2pgprot(_PAGE_CACHE_MODE_WC),
+ __pgprot(_PAGE_CACHE_MASK),
+ 0, 0, NULL);
+ }
+ return ret;
+}
+
+int set_memory_wc(unsigned long addr, int numpages)
+{
+ int ret;
+
+ ret = reserve_memtype(__pa(addr), __pa(addr) + numpages * PAGE_SIZE,
+ _PAGE_CACHE_MODE_WC, NULL);
+ if (ret)
+ return ret;
+
+ ret = _set_memory_wc(addr, numpages);
+ if (ret)
+ free_memtype(__pa(addr), __pa(addr) + numpages * PAGE_SIZE);
+
+ return ret;
+}
+EXPORT_SYMBOL(set_memory_wc);
+
+int _set_memory_wt(unsigned long addr, int numpages)
+{
+ return change_page_attr_set(&addr, numpages,
+ cachemode2pgprot(_PAGE_CACHE_MODE_WT), 0);
+}
+
+int _set_memory_wb(unsigned long addr, int numpages)
+{
+ /* WB cache mode is hard wired to all cache attribute bits being 0 */
+ return change_page_attr_clear(&addr, numpages,
+ __pgprot(_PAGE_CACHE_MASK), 0);
+}
+
+int set_memory_wb(unsigned long addr, int numpages)
+{
+ int ret;
+
+ ret = _set_memory_wb(addr, numpages);
+ if (ret)
+ return ret;
+
+ free_memtype(__pa(addr), __pa(addr) + numpages * PAGE_SIZE);
+ return 0;
+}
+EXPORT_SYMBOL(set_memory_wb);
+
+int set_memory_x(unsigned long addr, int numpages)
+{
+ if (!(__supported_pte_mask & _PAGE_NX))
+ return 0;
+
+ return change_page_attr_clear(&addr, numpages, __pgprot(_PAGE_NX), 0);
+}
+
+int set_memory_nx(unsigned long addr, int numpages)
+{
+ if (!(__supported_pte_mask & _PAGE_NX))
+ return 0;
+
+ return change_page_attr_set(&addr, numpages, __pgprot(_PAGE_NX), 0);
+}
+
+int set_memory_ro(unsigned long addr, int numpages)
+{
+ return change_page_attr_clear(&addr, numpages, __pgprot(_PAGE_RW), 0);
+}
+
+int set_memory_rw(unsigned long addr, int numpages)
+{
+ return change_page_attr_set(&addr, numpages, __pgprot(_PAGE_RW), 0);
+}
+
+int set_memory_np(unsigned long addr, int numpages)
+{
+ return change_page_attr_clear(&addr, numpages, __pgprot(_PAGE_PRESENT), 0);
+}
+
+int set_memory_np_noalias(unsigned long addr, int numpages)
+{
+ int cpa_flags = CPA_NO_CHECK_ALIAS;
+
+ return change_page_attr_set_clr(&addr, numpages, __pgprot(0),
+ __pgprot(_PAGE_PRESENT), 0,
+ cpa_flags, NULL);
+}
+
+int set_memory_4k(unsigned long addr, int numpages)
+{
+ return change_page_attr_set_clr(&addr, numpages, __pgprot(0),
+ __pgprot(0), 1, 0, NULL);
+}
+
+int set_memory_nonglobal(unsigned long addr, int numpages)
+{
+ return change_page_attr_clear(&addr, numpages,
+ __pgprot(_PAGE_GLOBAL), 0);
+}
+
+int set_memory_global(unsigned long addr, int numpages)
+{
+ return change_page_attr_set(&addr, numpages,
+ __pgprot(_PAGE_GLOBAL), 0);
+}
+
+static int __set_memory_enc_dec(unsigned long addr, int numpages, bool enc)
+{
+ struct cpa_data cpa;
+ int ret;
+
+ /* Nothing to do if memory encryption is not active */
+ if (!mem_encrypt_active())
+ return 0;
+
+ /* Should not be working on unaligned addresses */
+ if (WARN_ONCE(addr & ~PAGE_MASK, "misaligned address: %#lx\n", addr))
+ addr &= PAGE_MASK;
+
+ memset(&cpa, 0, sizeof(cpa));
+ cpa.vaddr = &addr;
+ cpa.numpages = numpages;
+ cpa.mask_set = enc ? __pgprot(_PAGE_ENC) : __pgprot(0);
+ cpa.mask_clr = enc ? __pgprot(0) : __pgprot(_PAGE_ENC);
+ cpa.pgd = init_mm.pgd;
+
+ /* Must avoid aliasing mappings in the highmem code */
+ kmap_flush_unused();
+ vm_unmap_aliases();
+
+ /*
+ * Before changing the encryption attribute, we need to flush caches.
+ */
+ cpa_flush(&cpa, 1);
+
+ ret = __change_page_attr_set_clr(&cpa, 1);
+
+ /*
+ * After changing the encryption attribute, we need to flush TLBs again
+ * in case any speculative TLB caching occurred (but no need to flush
+ * caches again). We could just use cpa_flush_all(), but in case TLB
+ * flushing gets optimized in the cpa_flush() path use the same logic
+ * as above.
+ */
+ cpa_flush(&cpa, 0);
+
+ return ret;
+}
+
+int set_memory_encrypted(unsigned long addr, int numpages)
+{
+ return __set_memory_enc_dec(addr, numpages, true);
+}
+EXPORT_SYMBOL_GPL(set_memory_encrypted);
+
+int set_memory_decrypted(unsigned long addr, int numpages)
+{
+ return __set_memory_enc_dec(addr, numpages, false);
+}
+EXPORT_SYMBOL_GPL(set_memory_decrypted);
+
+int set_pages_uc(struct page *page, int numpages)
+{
+ unsigned long addr = (unsigned long)page_address(page);
+
+ return set_memory_uc(addr, numpages);
+}
+EXPORT_SYMBOL(set_pages_uc);
+
+static int _set_pages_array(struct page **pages, int numpages,
+ enum page_cache_mode new_type)
+{
+ unsigned long start;
+ unsigned long end;
+ enum page_cache_mode set_type;
+ int i;
+ int free_idx;
+ int ret;
+
+ for (i = 0; i < numpages; i++) {
+ if (PageHighMem(pages[i]))
+ continue;
+ start = page_to_pfn(pages[i]) << PAGE_SHIFT;
+ end = start + PAGE_SIZE;
+ if (reserve_memtype(start, end, new_type, NULL))
+ goto err_out;
+ }
+
+ /* If WC, set to UC- first and then WC */
+ set_type = (new_type == _PAGE_CACHE_MODE_WC) ?
+ _PAGE_CACHE_MODE_UC_MINUS : new_type;
+
+ ret = cpa_set_pages_array(pages, numpages,
+ cachemode2pgprot(set_type));
+ if (!ret && new_type == _PAGE_CACHE_MODE_WC)
+ ret = change_page_attr_set_clr(NULL, numpages,
+ cachemode2pgprot(
+ _PAGE_CACHE_MODE_WC),
+ __pgprot(_PAGE_CACHE_MASK),
+ 0, CPA_PAGES_ARRAY, pages);
+ if (ret)
+ goto err_out;
+ return 0; /* Success */
+err_out:
+ free_idx = i;
+ for (i = 0; i < free_idx; i++) {
+ if (PageHighMem(pages[i]))
+ continue;
+ start = page_to_pfn(pages[i]) << PAGE_SHIFT;
+ end = start + PAGE_SIZE;
+ free_memtype(start, end);
+ }
+ return -EINVAL;
+}
+
+int set_pages_array_uc(struct page **pages, int numpages)
+{
+ return _set_pages_array(pages, numpages, _PAGE_CACHE_MODE_UC_MINUS);
+}
+EXPORT_SYMBOL(set_pages_array_uc);
+
+int set_pages_array_wc(struct page **pages, int numpages)
+{
+ return _set_pages_array(pages, numpages, _PAGE_CACHE_MODE_WC);
+}
+EXPORT_SYMBOL(set_pages_array_wc);
+
+int set_pages_array_wt(struct page **pages, int numpages)
+{
+ return _set_pages_array(pages, numpages, _PAGE_CACHE_MODE_WT);
+}
+EXPORT_SYMBOL_GPL(set_pages_array_wt);
+
+int set_pages_wb(struct page *page, int numpages)
+{
+ unsigned long addr = (unsigned long)page_address(page);
+
+ return set_memory_wb(addr, numpages);
+}
+EXPORT_SYMBOL(set_pages_wb);
+
+int set_pages_array_wb(struct page **pages, int numpages)
+{
+ int retval;
+ unsigned long start;
+ unsigned long end;
+ int i;
+
+ /* WB cache mode is hard wired to all cache attribute bits being 0 */
+ retval = cpa_clear_pages_array(pages, numpages,
+ __pgprot(_PAGE_CACHE_MASK));
+ if (retval)
+ return retval;
+
+ for (i = 0; i < numpages; i++) {
+ if (PageHighMem(pages[i]))
+ continue;
+ start = page_to_pfn(pages[i]) << PAGE_SHIFT;
+ end = start + PAGE_SIZE;
+ free_memtype(start, end);
+ }
+
+ return 0;
+}
+EXPORT_SYMBOL(set_pages_array_wb);
+
+int set_pages_ro(struct page *page, int numpages)
+{
+ unsigned long addr = (unsigned long)page_address(page);
+
+ return set_memory_ro(addr, numpages);
+}
+
+int set_pages_rw(struct page *page, int numpages)
+{
+ unsigned long addr = (unsigned long)page_address(page);
+
+ return set_memory_rw(addr, numpages);
+}
+
+static int __set_pages_p(struct page *page, int numpages)
+{
+ unsigned long tempaddr = (unsigned long) page_address(page);
+ struct cpa_data cpa = { .vaddr = &tempaddr,
+ .pgd = NULL,
+ .numpages = numpages,
+ .mask_set = __pgprot(_PAGE_PRESENT | _PAGE_RW),
+ .mask_clr = __pgprot(0),
+ .flags = 0};
+
+ /*
+ * No alias checking needed for setting present flag. otherwise,
+ * we may need to break large pages for 64-bit kernel text
+ * mappings (this adds to complexity if we want to do this from
+ * atomic context especially). Let's keep it simple!
+ */
+ return __change_page_attr_set_clr(&cpa, 0);
+}
+
+static int __set_pages_np(struct page *page, int numpages)
+{
+ unsigned long tempaddr = (unsigned long) page_address(page);
+ struct cpa_data cpa = { .vaddr = &tempaddr,
+ .pgd = NULL,
+ .numpages = numpages,
+ .mask_set = __pgprot(0),
+ .mask_clr = __pgprot(_PAGE_PRESENT | _PAGE_RW),
+ .flags = 0};
+
+ /*
+ * No alias checking needed for setting not present flag. otherwise,
+ * we may need to break large pages for 64-bit kernel text
+ * mappings (this adds to complexity if we want to do this from
+ * atomic context especially). Let's keep it simple!
+ */
+ return __change_page_attr_set_clr(&cpa, 0);
+}
+
+int set_direct_map_invalid_noflush(struct page *page)
+{
+ return __set_pages_np(page, 1);
+}
+
+int set_direct_map_default_noflush(struct page *page)
+{
+ return __set_pages_p(page, 1);
+}
+
+void __kernel_map_pages(struct page *page, int numpages, int enable)
+{
+ if (PageHighMem(page))
+ return;
+ if (!enable) {
+ debug_check_no_locks_freed(page_address(page),
+ numpages * PAGE_SIZE);
+ }
+
+ /*
+ * The return value is ignored as the calls cannot fail.
+ * Large pages for identity mappings are not used at boot time
+ * and hence no memory allocations during large page split.
+ */
+ if (enable)
+ __set_pages_p(page, numpages);
+ else
+ __set_pages_np(page, numpages);
+
+ /*
+ * We should perform an IPI and flush all tlbs,
+ * but that can deadlock->flush only current cpu.
+ * Preemption needs to be disabled around __flush_tlb_all() due to
+ * CR3 reload in __native_flush_tlb().
+ */
+ preempt_disable();
+ __flush_tlb_all();
+ preempt_enable();
+
+ arch_flush_lazy_mmu_mode();
+}
+
+#ifdef CONFIG_HIBERNATION
+bool kernel_page_present(struct page *page)
+{
+ unsigned int level;
+ pte_t *pte;
+
+ if (PageHighMem(page))
+ return false;
+
+ pte = lookup_address((unsigned long)page_address(page), &level);
+ return (pte_val(*pte) & _PAGE_PRESENT);
+}
+#endif /* CONFIG_HIBERNATION */
+
+int __init kernel_map_pages_in_pgd(pgd_t *pgd, u64 pfn, unsigned long address,
+ unsigned numpages, unsigned long page_flags)
+{
+ int retval = -EINVAL;
+
+ struct cpa_data cpa = {
+ .vaddr = &address,
+ .pfn = pfn,
+ .pgd = pgd,
+ .numpages = numpages,
+ .mask_set = __pgprot(0),
+ .mask_clr = __pgprot(0),
+ .flags = 0,
+ };
+
+ WARN_ONCE(num_online_cpus() > 1, "Don't call after initializing SMP");
+
+ if (!(__supported_pte_mask & _PAGE_NX))
+ goto out;
+
+ if (!(page_flags & _PAGE_NX))
+ cpa.mask_clr = __pgprot(_PAGE_NX);
+
+ if (!(page_flags & _PAGE_RW))
+ cpa.mask_clr = __pgprot(_PAGE_RW);
+
+ if (!(page_flags & _PAGE_ENC))
+ cpa.mask_clr = pgprot_encrypted(cpa.mask_clr);
+
+ cpa.mask_set = __pgprot(_PAGE_PRESENT | page_flags);
+
+ retval = __change_page_attr_set_clr(&cpa, 0);
+ __flush_tlb_all();
+
+out:
+ return retval;
+}
+
+/*
+ * __flush_tlb_all() flushes mappings only on current CPU and hence this
+ * function shouldn't be used in an SMP environment. Presently, it's used only
+ * during boot (way before smp_init()) by EFI subsystem and hence is ok.
+ */
+int __init kernel_unmap_pages_in_pgd(pgd_t *pgd, unsigned long address,
+ unsigned long numpages)
+{
+ int retval;
+
+ /*
+ * The typical sequence for unmapping is to find a pte through
+ * lookup_address_in_pgd() (ideally, it should never return NULL because
+ * the address is already mapped) and change it's protections. As pfn is
+ * the *target* of a mapping, it's not useful while unmapping.
+ */
+ struct cpa_data cpa = {
+ .vaddr = &address,
+ .pfn = 0,
+ .pgd = pgd,
+ .numpages = numpages,
+ .mask_set = __pgprot(0),
+ .mask_clr = __pgprot(_PAGE_PRESENT | _PAGE_RW),
+ .flags = 0,
+ };
+
+ WARN_ONCE(num_online_cpus() > 1, "Don't call after initializing SMP");
+
+ retval = __change_page_attr_set_clr(&cpa, 0);
+ __flush_tlb_all();
+
+ return retval;
+}
+
+/*
+ * The testcases use internal knowledge of the implementation that shouldn't
+ * be exposed to the rest of the kernel. Include these directly here.
+ */
+#ifdef CONFIG_CPA_DEBUG
+#include "cpa-test.c"
+#endif
diff --git a/arch/x86/mm/pat_internal.h b/arch/x86/mm/pat_internal.h
deleted file mode 100644
index 23ce8cd..0000000
--- a/arch/x86/mm/pat_internal.h
+++ /dev/null
@@ -1,49 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0 */
-#ifndef __PAT_INTERNAL_H_
-#define __PAT_INTERNAL_H_
-
-extern int pat_debug_enable;
-
-#define dprintk(fmt, arg...) \
- do { if (pat_debug_enable) pr_info("x86/PAT: " fmt, ##arg); } while (0)
-
-struct memtype {
- u64 start;
- u64 end;
- u64 subtree_max_end;
- enum page_cache_mode type;
- struct rb_node rb;
-};
-
-static inline char *cattr_name(enum page_cache_mode pcm)
-{
- switch (pcm) {
- case _PAGE_CACHE_MODE_UC: return "uncached";
- case _PAGE_CACHE_MODE_UC_MINUS: return "uncached-minus";
- case _PAGE_CACHE_MODE_WB: return "write-back";
- case _PAGE_CACHE_MODE_WC: return "write-combining";
- case _PAGE_CACHE_MODE_WT: return "write-through";
- case _PAGE_CACHE_MODE_WP: return "write-protected";
- default: return "broken";
- }
-}
-
-#ifdef CONFIG_X86_PAT
-extern int memtype_check_insert(struct memtype *entry_new,
- enum page_cache_mode *new_type);
-extern struct memtype *memtype_erase(u64 start, u64 end);
-extern struct memtype *memtype_lookup(u64 addr);
-extern int memtype_copy_nth_element(struct memtype *entry_out, loff_t pos);
-#else
-static inline int memtype_check_insert(struct memtype *entry_new,
- enum page_cache_mode *new_type)
-{ return 0; }
-static inline struct memtype *memtype_erase(u64 start, u64 end)
-{ return NULL; }
-static inline struct memtype *memtype_lookup(u64 addr)
-{ return NULL; }
-static inline int memtype_copy_nth_element(struct memtype *out, loff_t pos)
-{ return 0; }
-#endif
-
-#endif /* __PAT_INTERNAL_H_ */
diff --git a/arch/x86/mm/pat_interval.c b/arch/x86/mm/pat_interval.c
deleted file mode 100644
index 3c983de..0000000
--- a/arch/x86/mm/pat_interval.c
+++ /dev/null
@@ -1,194 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0
-/*
- * Handle caching attributes in page tables (PAT)
- *
- * Authors: Venkatesh Pallipadi <venkatesh.pallipadi@...el.com>
- * Suresh B Siddha <suresh.b.siddha@...el.com>
- *
- * Interval tree used to store the PAT memory type reservations.
- */
-
-#include <linux/seq_file.h>
-#include <linux/debugfs.h>
-#include <linux/kernel.h>
-#include <linux/interval_tree_generic.h>
-#include <linux/sched.h>
-#include <linux/gfp.h>
-
-#include <asm/pgtable.h>
-#include <asm/pat.h>
-
-#include "pat_internal.h"
-
-/*
- * The memtype tree keeps track of memory type for specific
- * physical memory areas. Without proper tracking, conflicting memory
- * types in different mappings can cause CPU cache corruption.
- *
- * The tree is an interval tree (augmented rbtree) which tree is ordered
- * by the starting address. The tree can contain multiple entries for
- * different regions which overlap. All the aliases have the same
- * cache attributes of course, as enforced by the PAT logic.
- *
- * memtype_lock protects the rbtree.
- */
-
-static inline u64 interval_start(struct memtype *entry)
-{
- return entry->start;
-}
-
-static inline u64 interval_end(struct memtype *entry)
-{
- return entry->end - 1;
-}
-
-INTERVAL_TREE_DEFINE(struct memtype, rb, u64, subtree_max_end,
- interval_start, interval_end,
- static, interval)
-
-static struct rb_root_cached memtype_rbroot = RB_ROOT_CACHED;
-
-enum {
- MEMTYPE_EXACT_MATCH = 0,
- MEMTYPE_END_MATCH = 1
-};
-
-static struct memtype *memtype_match(u64 start, u64 end, int match_type)
-{
- struct memtype *entry_match;
-
- entry_match = interval_iter_first(&memtype_rbroot, start, end-1);
-
- while (entry_match != NULL && entry_match->start < end) {
- if ((match_type == MEMTYPE_EXACT_MATCH) &&
- (entry_match->start == start) && (entry_match->end == end))
- return entry_match;
-
- if ((match_type == MEMTYPE_END_MATCH) &&
- (entry_match->start < start) && (entry_match->end == end))
- return entry_match;
-
- entry_match = interval_iter_next(entry_match, start, end-1);
- }
-
- return NULL; /* Returns NULL if there is no match */
-}
-
-static int memtype_check_conflict(u64 start, u64 end,
- enum page_cache_mode reqtype,
- enum page_cache_mode *newtype)
-{
- struct memtype *entry_match;
- enum page_cache_mode found_type = reqtype;
-
- entry_match = interval_iter_first(&memtype_rbroot, start, end-1);
- if (entry_match == NULL)
- goto success;
-
- if (entry_match->type != found_type && newtype == NULL)
- goto failure;
-
- dprintk("Overlap at 0x%Lx-0x%Lx\n", entry_match->start, entry_match->end);
- found_type = entry_match->type;
-
- entry_match = interval_iter_next(entry_match, start, end-1);
- while (entry_match) {
- if (entry_match->type != found_type)
- goto failure;
-
- entry_match = interval_iter_next(entry_match, start, end-1);
- }
-success:
- if (newtype)
- *newtype = found_type;
-
- return 0;
-
-failure:
- pr_info("x86/PAT: %s:%d conflicting memory types %Lx-%Lx %s<->%s\n",
- current->comm, current->pid, start, end,
- cattr_name(found_type), cattr_name(entry_match->type));
-
- return -EBUSY;
-}
-
-int memtype_check_insert(struct memtype *entry_new, enum page_cache_mode *ret_type)
-{
- int err = 0;
-
- err = memtype_check_conflict(entry_new->start, entry_new->end, entry_new->type, ret_type);
- if (err)
- return err;
-
- if (ret_type)
- entry_new->type = *ret_type;
-
- interval_insert(entry_new, &memtype_rbroot);
- return 0;
-}
-
-struct memtype *memtype_erase(u64 start, u64 end)
-{
- struct memtype *entry_old;
-
- /*
- * Since the memtype_rbroot tree allows overlapping ranges,
- * memtype_erase() checks with EXACT_MATCH first, i.e. free
- * a whole node for the munmap case. If no such entry is found,
- * it then checks with END_MATCH, i.e. shrink the size of a node
- * from the end for the mremap case.
- */
- entry_old = memtype_match(start, end, MEMTYPE_EXACT_MATCH);
- if (!entry_old) {
- entry_old = memtype_match(start, end, MEMTYPE_END_MATCH);
- if (!entry_old)
- return ERR_PTR(-EINVAL);
- }
-
- if (entry_old->start == start) {
- /* munmap: erase this node */
- interval_remove(entry_old, &memtype_rbroot);
- } else {
- /* mremap: update the end value of this node */
- interval_remove(entry_old, &memtype_rbroot);
- entry_old->end = start;
- interval_insert(entry_old, &memtype_rbroot);
-
- return NULL;
- }
-
- return entry_old;
-}
-
-struct memtype *memtype_lookup(u64 addr)
-{
- return interval_iter_first(&memtype_rbroot, addr, addr + PAGE_SIZE-1);
-}
-
-/*
- * Debugging helper, copy the Nth entry of the tree into a
- * a copy for printout. This allows us to print out the tree
- * via debugfs, without holding the memtype_lock too long:
- */
-#ifdef CONFIG_DEBUG_FS
-int memtype_copy_nth_element(struct memtype *entry_out, loff_t pos)
-{
- struct memtype *entry_match;
- int i = 1;
-
- entry_match = interval_iter_first(&memtype_rbroot, 0, ULONG_MAX);
-
- while (entry_match && pos != i) {
- entry_match = interval_iter_next(entry_match, 0, ULONG_MAX);
- i++;
- }
-
- if (entry_match) { /* pos == i */
- *entry_out = *entry_match;
- return 0;
- } else {
- return 1;
- }
-}
-#endif
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