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Date: Fri, 17 Feb 2017 17:13:13 +0300
From: "Kirill A. Shutemov" <kirill.shutemov@...ux.intel.com>
To: Linus Torvalds <torvalds@...ux-foundation.org>,
Andrew Morton <akpm@...ux-foundation.org>, x86@...nel.org,
Thomas Gleixner <tglx@...utronix.de>,
Ingo Molnar <mingo@...hat.com>, Arnd Bergmann <arnd@...db.de>,
"H. Peter Anvin" <hpa@...or.com>
Cc: Andi Kleen <ak@...ux.intel.com>,
Dave Hansen <dave.hansen@...el.com>,
Andy Lutomirski <luto@...capital.net>,
linux-arch@...r.kernel.org, linux-mm@...ck.org,
linux-kernel@...r.kernel.org,
"Kirill A. Shutemov" <kirill.shutemov@...ux.intel.com>,
Xiong Zhang <xiong.y.zhang@...el.com>
Subject: [PATCHv3 18/33] x86/xen: convert __xen_pgd_walk() and xen_cleanmfnmap() to support p4d
Split these helpers few per-level functions and add p4d support.
Signed-off-by: Xiong Zhang <xiong.y.zhang@...el.com>
[kirill.shutemov@...ux.intel.com: split off into separate patch]
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@...ux.intel.com>
---
arch/x86/xen/mmu.c | 243 ++++++++++++++++++++++++++++++++---------------------
arch/x86/xen/mmu.h | 1 +
2 files changed, 148 insertions(+), 96 deletions(-)
diff --git a/arch/x86/xen/mmu.c b/arch/x86/xen/mmu.c
index 7d5afdb417cc..88c704caf2c1 100644
--- a/arch/x86/xen/mmu.c
+++ b/arch/x86/xen/mmu.c
@@ -593,6 +593,62 @@ static void xen_set_pgd(pgd_t *ptr, pgd_t val)
}
#endif /* CONFIG_PGTABLE_LEVELS == 4 */
+static int xen_pmd_walk(struct mm_struct *mm, pmd_t *pmd,
+ int (*func)(struct mm_struct *mm, struct page *, enum pt_level),
+ bool last, unsigned long limit)
+{
+ int i, nr, flush = 0;
+
+ nr = last ? pmd_index(limit) + 1 : PTRS_PER_PMD;
+ for (i = 0; i < nr; i++) {
+ if (!pmd_none(pmd[i]))
+ flush |= (*func)(mm, pmd_page(pmd[i]), PT_PTE);
+ }
+ return flush;
+}
+
+static int xen_pud_walk(struct mm_struct *mm, pud_t *pud,
+ int (*func)(struct mm_struct *mm, struct page *, enum pt_level),
+ bool last, unsigned long limit)
+{
+ int i, nr, flush = 0;
+
+ nr = last ? pud_index(limit) + 1 : PTRS_PER_PUD;
+ for (i = 0; i < nr; i++) {
+ pmd_t *pmd;
+
+ if (pud_none(pud[i]))
+ continue;
+
+ pmd = pmd_offset(&pud[i], 0);
+ if (PTRS_PER_PMD > 1)
+ flush |= (*func)(mm, virt_to_page(pmd), PT_PMD);
+ xen_pmd_walk(mm, pmd, func, last && i == nr - 1, limit);
+ }
+ return flush;
+}
+
+static int xen_p4d_walk(struct mm_struct *mm, p4d_t *p4d,
+ int (*func)(struct mm_struct *mm, struct page *, enum pt_level),
+ bool last, unsigned long limit)
+{
+ int i, nr, flush = 0;
+
+ nr = last ? p4d_index(limit) + 1 : PTRS_PER_P4D;
+ for (i = 0; i < nr; i++) {
+ pud_t *pud;
+
+ if (p4d_none(p4d[i]))
+ continue;
+
+ pud = pud_offset(&p4d[i], 0);
+ if (PTRS_PER_PUD > 1)
+ flush |= (*func)(mm, virt_to_page(pud), PT_PUD);
+ xen_pud_walk(mm, pud, func, last && i == nr - 1, limit);
+ }
+ return flush;
+}
+
/*
* (Yet another) pagetable walker. This one is intended for pinning a
* pagetable. This means that it walks a pagetable and calls the
@@ -613,10 +669,8 @@ static int __xen_pgd_walk(struct mm_struct *mm, pgd_t *pgd,
enum pt_level),
unsigned long limit)
{
- int flush = 0;
+ int i, nr, flush = 0;
unsigned hole_low, hole_high;
- unsigned pgdidx_limit, pudidx_limit, pmdidx_limit;
- unsigned pgdidx, pudidx, pmdidx;
/* The limit is the last byte to be touched */
limit--;
@@ -633,65 +687,22 @@ static int __xen_pgd_walk(struct mm_struct *mm, pgd_t *pgd,
hole_low = pgd_index(USER_LIMIT);
hole_high = pgd_index(PAGE_OFFSET);
- pgdidx_limit = pgd_index(limit);
-#if PTRS_PER_PUD > 1
- pudidx_limit = pud_index(limit);
-#else
- pudidx_limit = 0;
-#endif
-#if PTRS_PER_PMD > 1
- pmdidx_limit = pmd_index(limit);
-#else
- pmdidx_limit = 0;
-#endif
-
- for (pgdidx = 0; pgdidx <= pgdidx_limit; pgdidx++) {
- pud_t *pud;
+ nr = pgd_index(limit) + 1;
+ for (i = 0; i < nr; i++) {
+ p4d_t *p4d;
- if (pgdidx >= hole_low && pgdidx < hole_high)
+ if (i >= hole_low && i < hole_high)
continue;
- if (!pgd_val(pgd[pgdidx]))
+ if (pgd_none(pgd[i]))
continue;
- pud = pud_offset(&pgd[pgdidx], 0);
-
- if (PTRS_PER_PUD > 1) /* not folded */
- flush |= (*func)(mm, virt_to_page(pud), PT_PUD);
-
- for (pudidx = 0; pudidx < PTRS_PER_PUD; pudidx++) {
- pmd_t *pmd;
-
- if (pgdidx == pgdidx_limit &&
- pudidx > pudidx_limit)
- goto out;
-
- if (pud_none(pud[pudidx]))
- continue;
-
- pmd = pmd_offset(&pud[pudidx], 0);
-
- if (PTRS_PER_PMD > 1) /* not folded */
- flush |= (*func)(mm, virt_to_page(pmd), PT_PMD);
-
- for (pmdidx = 0; pmdidx < PTRS_PER_PMD; pmdidx++) {
- struct page *pte;
-
- if (pgdidx == pgdidx_limit &&
- pudidx == pudidx_limit &&
- pmdidx > pmdidx_limit)
- goto out;
-
- if (pmd_none(pmd[pmdidx]))
- continue;
-
- pte = pmd_page(pmd[pmdidx]);
- flush |= (*func)(mm, pte, PT_PTE);
- }
- }
+ p4d = p4d_offset(&pgd[i], 0);
+ if (PTRS_PER_P4D > 1)
+ flush |= (*func)(mm, virt_to_page(p4d), PT_P4D);
+ xen_p4d_walk(mm, p4d, func, i == nr - 1, limit);
}
-out:
/* Do the top level last, so that the callbacks can use it as
a cue to do final things like tlb flushes. */
flush |= (*func)(mm, virt_to_page(pgd), PT_PGD);
@@ -1150,57 +1161,97 @@ static void __init xen_cleanmfnmap_free_pgtbl(void *pgtbl, bool unpin)
xen_free_ro_pages(pa, PAGE_SIZE);
}
+static void __init xen_cleanmfnmap_pmd(pmd_t *pmd, bool unpin)
+{
+ unsigned long pa;
+ pte_t *pte_tbl;
+ int i;
+
+ if (pmd_large(*pmd)) {
+ pa = pmd_val(*pmd) & PHYSICAL_PAGE_MASK;
+ xen_free_ro_pages(pa, PMD_SIZE);
+ return;
+ }
+
+ pte_tbl = pte_offset_kernel(pmd, 0);
+ for (i = 0; i < PTRS_PER_PTE; i++) {
+ if (pte_none(pte_tbl[i]))
+ continue;
+ pa = pte_pfn(pte_tbl[i]) << PAGE_SHIFT;
+ xen_free_ro_pages(pa, PAGE_SIZE);
+ }
+ set_pmd(pmd, __pmd(0));
+ xen_cleanmfnmap_free_pgtbl(pte_tbl, unpin);
+}
+
+static void __init xen_cleanmfnmap_pud(pud_t *pud, bool unpin)
+{
+ unsigned long pa;
+ pmd_t *pmd_tbl;
+ int i;
+
+ if (pud_large(*pud)) {
+ pa = pud_val(*pud) & PHYSICAL_PAGE_MASK;
+ xen_free_ro_pages(pa, PUD_SIZE);
+ return;
+ }
+
+ pmd_tbl = pmd_offset(pud, 0);
+ for (i = 0; i < PTRS_PER_PMD; i++) {
+ if (pmd_none(pmd_tbl[i]))
+ continue;
+ xen_cleanmfnmap_pmd(pmd_tbl + i, unpin);
+ }
+ set_pud(pud, __pud(0));
+ xen_cleanmfnmap_free_pgtbl(pmd_tbl, unpin);
+}
+
+static void __init xen_cleanmfnmap_p4d(p4d_t *p4d, bool unpin)
+{
+ unsigned long pa;
+ pud_t *pud_tbl;
+ int i;
+
+ if (p4d_large(*p4d)) {
+ pa = p4d_val(*p4d) & PHYSICAL_PAGE_MASK;
+ xen_free_ro_pages(pa, P4D_SIZE);
+ return;
+ }
+
+ pud_tbl = pud_offset(p4d, 0);
+ for (i = 0; i < PTRS_PER_PUD; i++) {
+ if (pud_none(pud_tbl[i]))
+ continue;
+ xen_cleanmfnmap_pud(pud_tbl + i, unpin);
+ }
+ set_p4d(p4d, __p4d(0));
+ xen_cleanmfnmap_free_pgtbl(pud_tbl, unpin);
+}
+
/*
* Since it is well isolated we can (and since it is perhaps large we should)
* also free the page tables mapping the initial P->M table.
*/
static void __init xen_cleanmfnmap(unsigned long vaddr)
{
- unsigned long va = vaddr & PMD_MASK;
- unsigned long pa;
- pgd_t *pgd = pgd_offset_k(va);
- pud_t *pud_page = pud_offset(pgd, 0);
- pud_t *pud;
- pmd_t *pmd;
- pte_t *pte;
+ pgd_t *pgd;
+ p4d_t *p4d;
unsigned int i;
bool unpin;
unpin = (vaddr == 2 * PGDIR_SIZE);
- set_pgd(pgd, __pgd(0));
- do {
- pud = pud_page + pud_index(va);
- if (pud_none(*pud)) {
- va += PUD_SIZE;
- } else if (pud_large(*pud)) {
- pa = pud_val(*pud) & PHYSICAL_PAGE_MASK;
- xen_free_ro_pages(pa, PUD_SIZE);
- va += PUD_SIZE;
- } else {
- pmd = pmd_offset(pud, va);
- if (pmd_large(*pmd)) {
- pa = pmd_val(*pmd) & PHYSICAL_PAGE_MASK;
- xen_free_ro_pages(pa, PMD_SIZE);
- } else if (!pmd_none(*pmd)) {
- pte = pte_offset_kernel(pmd, va);
- set_pmd(pmd, __pmd(0));
- for (i = 0; i < PTRS_PER_PTE; ++i) {
- if (pte_none(pte[i]))
- break;
- pa = pte_pfn(pte[i]) << PAGE_SHIFT;
- xen_free_ro_pages(pa, PAGE_SIZE);
- }
- xen_cleanmfnmap_free_pgtbl(pte, unpin);
- }
- va += PMD_SIZE;
- if (pmd_index(va))
- continue;
- set_pud(pud, __pud(0));
- xen_cleanmfnmap_free_pgtbl(pmd, unpin);
- }
-
- } while (pud_index(va) || pmd_index(va));
- xen_cleanmfnmap_free_pgtbl(pud_page, unpin);
+ vaddr &= PMD_MASK;
+ pgd = pgd_offset_k(vaddr);
+ p4d = p4d_offset(pgd, 0);
+ for (i = 0; i < PTRS_PER_P4D; i++) {
+ if (p4d_none(p4d[i]))
+ continue;
+ xen_cleanmfnmap_p4d(p4d + i, unpin);
+ }
+ if (IS_ENABLED(CONFIG_X86_5LEVEL)) {
+ set_pgd(pgd, __pgd(0));
+ xen_cleanmfnmap_free_pgtbl(p4d, unpin);
+ }
}
static void __init xen_pagetable_p2m_free(void)
diff --git a/arch/x86/xen/mmu.h b/arch/x86/xen/mmu.h
index 73809bb951b4..3fe2b3292915 100644
--- a/arch/x86/xen/mmu.h
+++ b/arch/x86/xen/mmu.h
@@ -5,6 +5,7 @@
enum pt_level {
PT_PGD,
+ PT_P4D,
PT_PUD,
PT_PMD,
PT_PTE
--
2.11.0
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