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Date: Tue, 22 Jul 2014 23:01:09 +0400
From: Max Filippov <jcmvbkbc@...il.com>
To: linux-xtensa@...ux-xtensa.org
Cc: Chris Zankel <chris@...kel.net>, Marc Gauthier <marc@...ence.com>,
linux-kernel@...r.kernel.org, Max Filippov <jcmvbkbc@...il.com>
Subject: [PATCH 4/8] xtensa: implement clear_user_highpage and copy_user_highpage
Existing clear_user_page and copy_user_page cannot be used with highmem
because they calculate physical page address from its virtual address
and do it incorrectly in case of high memory page mapped with
kmap_atomic. Also kmap is not needed, as most likely userspace mapping
color would be different from the kmapped color.
Provide clear_user_highpage and copy_user_highpage functions that
determine if temporary mapping is needed for the pages. Move most of the
logic of the former clear_user_page and copy_user_page to
xtensa/mm/cache.c only leaving temporary mapping setup, invalidation and
clearing/copying in the xtensa/mm/misc.S. Rename these functions to
clear_page_alias and copy_page_alias.
Signed-off-by: Max Filippov <jcmvbkbc@...il.com>
---
arch/xtensa/include/asm/cacheflush.h | 2 +
arch/xtensa/include/asm/page.h | 12 +++-
arch/xtensa/mm/cache.c | 63 +++++++++++++++++++
arch/xtensa/mm/misc.S | 116 ++++++++++++++++-------------------
4 files changed, 127 insertions(+), 66 deletions(-)
diff --git a/arch/xtensa/include/asm/cacheflush.h b/arch/xtensa/include/asm/cacheflush.h
index 555a98a..e72aaca 100644
--- a/arch/xtensa/include/asm/cacheflush.h
+++ b/arch/xtensa/include/asm/cacheflush.h
@@ -37,6 +37,7 @@
* specials for cache aliasing:
*
* __flush_invalidate_dcache_page_alias(vaddr,paddr)
+ * __invalidate_dcache_page_alias(vaddr,paddr)
* __invalidate_icache_page_alias(vaddr,paddr)
*/
@@ -62,6 +63,7 @@ extern void __flush_invalidate_dcache_range(unsigned long, unsigned long);
#if defined(CONFIG_MMU) && (DCACHE_WAY_SIZE > PAGE_SIZE)
extern void __flush_invalidate_dcache_page_alias(unsigned long, unsigned long);
+extern void __invalidate_dcache_page_alias(unsigned long, unsigned long);
#else
static inline void __flush_invalidate_dcache_page_alias(unsigned long virt,
unsigned long phys) { }
diff --git a/arch/xtensa/include/asm/page.h b/arch/xtensa/include/asm/page.h
index 47f5823..11721cc 100644
--- a/arch/xtensa/include/asm/page.h
+++ b/arch/xtensa/include/asm/page.h
@@ -134,6 +134,7 @@ static inline __attribute_const__ int get_order(unsigned long size)
#endif
struct page;
+struct vm_area_struct;
extern void clear_page(void *page);
extern void copy_page(void *to, void *from);
@@ -143,8 +144,15 @@ extern void copy_page(void *to, void *from);
*/
#if DCACHE_WAY_SIZE > PAGE_SIZE
-extern void clear_user_page(void*, unsigned long, struct page*);
-extern void copy_user_page(void*, void*, unsigned long, struct page*);
+extern void clear_page_alias(void *vaddr, unsigned long paddr);
+extern void copy_page_alias(void *to, void *from,
+ unsigned long to_paddr, unsigned long from_paddr);
+
+#define clear_user_highpage clear_user_highpage
+void clear_user_highpage(struct page *page, unsigned long vaddr);
+#define __HAVE_ARCH_COPY_USER_HIGHPAGE
+void copy_user_highpage(struct page *to, struct page *from,
+ unsigned long vaddr, struct vm_area_struct *vma);
#else
# define clear_user_page(page, vaddr, pg) clear_page(page)
# define copy_user_page(to, from, vaddr, pg) copy_page(to, from)
diff --git a/arch/xtensa/mm/cache.c b/arch/xtensa/mm/cache.c
index 63cbb86..96aea66 100644
--- a/arch/xtensa/mm/cache.c
+++ b/arch/xtensa/mm/cache.c
@@ -63,6 +63,69 @@
#error "HIGHMEM is not supported on cores with aliasing cache."
#endif
+#if (DCACHE_WAY_SIZE > PAGE_SIZE)
+static inline void kmap_invalidate_coherent(struct page *page,
+ unsigned long vaddr)
+{
+ if (!DCACHE_ALIAS_EQ(page_to_phys(page), vaddr)) {
+ unsigned long kvaddr;
+
+ if (!PageHighMem(page)) {
+ kvaddr = (unsigned long)page_to_virt(page);
+
+ __invalidate_dcache_page(kvaddr);
+ } else {
+ kvaddr = TLBTEMP_BASE_1 +
+ (page_to_phys(page) & DCACHE_ALIAS_MASK);
+
+ __invalidate_dcache_page_alias(kvaddr,
+ page_to_phys(page));
+ }
+ }
+}
+
+static inline void *coherent_kvaddr(struct page *page, unsigned long base,
+ unsigned long vaddr, unsigned long *paddr)
+{
+ if (PageHighMem(page) || !DCACHE_ALIAS_EQ(page_to_phys(page), vaddr)) {
+ *paddr = page_to_phys(page);
+ return (void *)(base + (vaddr & DCACHE_ALIAS_MASK));
+ } else {
+ *paddr = 0;
+ return page_to_virt(page);
+ }
+}
+
+void clear_user_highpage(struct page *page, unsigned long vaddr)
+{
+ unsigned long paddr;
+ void *kvaddr = coherent_kvaddr(page, TLBTEMP_BASE_1, vaddr, &paddr);
+
+ pagefault_disable();
+ kmap_invalidate_coherent(page, vaddr);
+ set_bit(PG_arch_1, &page->flags);
+ clear_page_alias(kvaddr, paddr);
+ pagefault_enable();
+}
+
+void copy_user_highpage(struct page *dst, struct page *src,
+ unsigned long vaddr, struct vm_area_struct *vma)
+{
+ unsigned long dst_paddr, src_paddr;
+ void *dst_vaddr = coherent_kvaddr(dst, TLBTEMP_BASE_1, vaddr,
+ &dst_paddr);
+ void *src_vaddr = coherent_kvaddr(src, TLBTEMP_BASE_2, vaddr,
+ &src_paddr);
+
+ pagefault_disable();
+ kmap_invalidate_coherent(dst, vaddr);
+ set_bit(PG_arch_1, &dst->flags);
+ copy_page_alias(dst_vaddr, src_vaddr, dst_paddr, src_paddr);
+ pagefault_enable();
+}
+
+#endif /* DCACHE_WAY_SIZE > PAGE_SIZE */
+
#if (DCACHE_WAY_SIZE > PAGE_SIZE) && XCHAL_DCACHE_IS_WRITEBACK
/*
diff --git a/arch/xtensa/mm/misc.S b/arch/xtensa/mm/misc.S
index 1f68558..11a01c3 100644
--- a/arch/xtensa/mm/misc.S
+++ b/arch/xtensa/mm/misc.S
@@ -110,41 +110,24 @@ ENTRY(__tlbtemp_mapping_start)
#if (DCACHE_WAY_SIZE > PAGE_SIZE)
/*
- * clear_user_page (void *addr, unsigned long vaddr, struct page *page)
- * a2 a3 a4
+ * clear_page_alias(void *addr, unsigned long paddr)
+ * a2 a3
*/
-ENTRY(clear_user_page)
+ENTRY(clear_page_alias)
entry a1, 32
- /* Mark page dirty and determine alias. */
+ /* Skip setting up a temporary DTLB if not aliased low page. */
- movi a7, (1 << PG_ARCH_1)
- l32i a5, a4, PAGE_FLAGS
- xor a6, a2, a3
- extui a3, a3, PAGE_SHIFT, DCACHE_ALIAS_ORDER
- extui a6, a6, PAGE_SHIFT, DCACHE_ALIAS_ORDER
- or a5, a5, a7
- slli a3, a3, PAGE_SHIFT
- s32i a5, a4, PAGE_FLAGS
+ movi a5, PAGE_OFFSET
+ movi a6, 0
+ beqz a3, 1f
- /* Skip setting up a temporary DTLB if not aliased. */
-
- beqz a6, 1f
-
- /* Invalidate kernel page. */
-
- mov a10, a2
- call8 __invalidate_dcache_page
-
- /* Setup a temporary DTLB with the color of the VPN */
-
- movi a4, ((PAGE_KERNEL | _PAGE_HW_WRITE) - PAGE_OFFSET) & 0xffffffff
- movi a5, TLBTEMP_BASE_1 # virt
- add a6, a2, a4 # ppn
- add a2, a5, a3 # add 'color'
+ /* Setup a temporary DTLB for the addr. */
+ addi a6, a3, (PAGE_KERNEL | _PAGE_HW_WRITE)
+ mov a4, a2
wdtlb a6, a2
dsync
@@ -165,62 +148,43 @@ ENTRY(clear_user_page)
/* We need to invalidate the temporary idtlb entry, if any. */
-1: addi a2, a2, -PAGE_SIZE
- idtlb a2
+1: idtlb a4
dsync
retw
-ENDPROC(clear_user_page)
+ENDPROC(clear_page_alias)
/*
- * copy_page_user (void *to, void *from, unsigned long vaddr, struct page *page)
- * a2 a3 a4 a5
+ * copy_page_alias(void *to, void *from,
+ * a2 a3
+ * unsigned long to_paddr, unsigned long from_paddr)
+ * a4 a5
*/
-ENTRY(copy_user_page)
+ENTRY(copy_page_alias)
entry a1, 32
- /* Mark page dirty and determine alias for destination. */
-
- movi a8, (1 << PG_ARCH_1)
- l32i a9, a5, PAGE_FLAGS
- xor a6, a2, a4
- xor a7, a3, a4
- extui a4, a4, PAGE_SHIFT, DCACHE_ALIAS_ORDER
- extui a6, a6, PAGE_SHIFT, DCACHE_ALIAS_ORDER
- extui a7, a7, PAGE_SHIFT, DCACHE_ALIAS_ORDER
- or a9, a9, a8
- slli a4, a4, PAGE_SHIFT
- s32i a9, a5, PAGE_FLAGS
- movi a5, ((PAGE_KERNEL | _PAGE_HW_WRITE) - PAGE_OFFSET) & 0xffffffff
-
- beqz a6, 1f
-
- /* Invalidate dcache */
-
- mov a10, a2
- call8 __invalidate_dcache_page
+ /* Skip setting up a temporary DTLB for destination if not aliased. */
- /* Setup a temporary DTLB with a matching color. */
+ movi a6, 0
+ movi a7, 0
+ beqz a4, 1f
- movi a8, TLBTEMP_BASE_1 # base
- add a6, a2, a5 # ppn
- add a2, a8, a4 # add 'color'
+ /* Setup a temporary DTLB for destination. */
+ addi a6, a4, (PAGE_KERNEL | _PAGE_HW_WRITE)
wdtlb a6, a2
dsync
- /* Skip setting up a temporary DTLB for destination if not aliased. */
+ /* Skip setting up a temporary DTLB for source if not aliased. */
-1: beqz a7, 1f
+1: beqz a5, 1f
- /* Setup a temporary DTLB with a matching color. */
+ /* Setup a temporary DTLB for source. */
- movi a8, TLBTEMP_BASE_2 # base
- add a7, a3, a5 # ppn
- add a3, a8, a4
+ addi a7, a5, PAGE_KERNEL
addi a8, a3, 1 # way1
wdtlb a7, a8
@@ -271,7 +235,7 @@ ENTRY(copy_user_page)
retw
-ENDPROC(copy_user_page)
+ENDPROC(copy_page_alias)
#endif
@@ -300,6 +264,30 @@ ENTRY(__flush_invalidate_dcache_page_alias)
retw
ENDPROC(__flush_invalidate_dcache_page_alias)
+
+/*
+ * void __invalidate_dcache_page_alias (addr, phys)
+ * a2 a3
+ */
+
+ENTRY(__invalidate_dcache_page_alias)
+
+ entry sp, 16
+
+ movi a7, 0 # required for exception handler
+ addi a6, a3, (PAGE_KERNEL | _PAGE_HW_WRITE)
+ mov a4, a2
+ wdtlb a6, a2
+ dsync
+
+ ___invalidate_dcache_page a2 a3
+
+ idtlb a4
+ dsync
+
+ retw
+
+ENDPROC(__invalidate_dcache_page_alias)
#endif
ENTRY(__tlbtemp_mapping_itlb)
--
1.8.1.4
--
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