block: add helpers to run flush_dcache_page() against a bio and a request's pages

Mtdblock driver doesn't call flush_dcache_page for pages in request.  So,
this causes problems on architectures where the icache doesn't fill from
the dcache or with dcache aliases.  The patch fixes this.

The ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE symbol was introduced to avoid
pointless empty cache-thrashing loops on architectures for which
flush_dcache_page() is a no-op.  Every architecture was provided with this
flush pages on architectires where ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE is
equal 1 or do nothing otherwise.

See "fix mtd_blkdevs problem with caches on some architectures" discussion
on LKML for more information.

Signed-off-by: Ilya Loginov <isloginov@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Peter Horton <phorton@bitbox.co.uk>
Cc: "Ed L. Cashin" <ecashin@coraid.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>

23 files changed, 26 insertions, 0 deletions

diff --git a/arch/alpha/include/asm/cacheflush.h b/arch/alpha/include/asm/cacheflush.h
index b686cc7fc44e..01d71e1c8a9e 100644
--- a/arch/alpha/include/asm/cacheflush.h
+++ b/arch/alpha/include/asm/cacheflush.h
@@ -9,6 +9,7 @@
 #define flush_cache_dup_mm(mm)                  do { } while (0)
 #define flush_cache_range(vma, start, end)      do { } while (0)
 #define flush_cache_page(vma, vmaddr, pfn)      do { } while (0)
+#define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 0
 #define flush_dcache_page(page)                 do { } while (0)
 #define flush_dcache_mmap_lock(mapping)         do { } while (0)
 #define flush_dcache_mmap_unlock(mapping)       do { } while (0)
diff --git a/arch/arm/include/asm/cacheflush.h b/arch/arm/include/asm/cacheflush.h
index fd03fb63a332..247b7b0adc2a 100644
--- a/arch/arm/include/asm/cacheflush.h
+++ b/arch/arm/include/asm/cacheflush.h
@@ -408,6 +408,7 @@ extern void flush_ptrace_access(struct vm_area_struct *vma, struct page *page,
  * about to change to user space.  This is the same method as used on SPARC64.
  * See update_mmu_cache for the user space part.
  */
+#define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 1
 extern void flush_dcache_page(struct page *);
 
 extern void __flush_dcache_page(struct address_space *mapping, struct page *page);
diff --git a/arch/avr32/include/asm/cacheflush.h b/arch/avr32/include/asm/cacheflush.h
index 670674749b20..96e53820bbbd 100644
--- a/arch/avr32/include/asm/cacheflush.h
+++ b/arch/avr32/include/asm/cacheflush.h
@@ -107,6 +107,7 @@ extern void flush_icache_page(struct vm_area_struct *vma, struct page *page);
  * do something here, but only for certain configurations.  No such
  * configurations exist at this time.
  */
+#define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 0
 #define flush_dcache_page(page)                 do { } while (0)
 #define flush_dcache_mmap_lock(page)            do { } while (0)
 #define flush_dcache_mmap_unlock(page)          do { } while (0)
diff --git a/arch/blackfin/include/asm/cacheflush.h b/arch/blackfin/include/asm/cacheflush.h
index af03a36c7a4e..417eaac7fe99 100644
--- a/arch/blackfin/include/asm/cacheflush.h
+++ b/arch/blackfin/include/asm/cacheflush.h
@@ -68,9 +68,11 @@ do { memcpy(dst, src, len);						\
 #endif
 #if defined(CONFIG_BFIN_EXTMEM_WRITEBACK) || defined(CONFIG_BFIN_L2_WRITEBACK)
 # define flush_dcache_range(start,end)          blackfin_dcache_flush_range((start), (end))
+#define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 1
 # define flush_dcache_page(page)                blackfin_dflush_page(page_address(page))
 #else
 # define flush_dcache_range(start,end)          do { } while (0)
+#define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 0
 # define flush_dcache_page(page)                do { } while (0)
 #endif
 
diff --git a/arch/cris/include/asm/cacheflush.h b/arch/cris/include/asm/cacheflush.h
index cf60e3f69f8d..36795bca605e 100644
--- a/arch/cris/include/asm/cacheflush.h
+++ b/arch/cris/include/asm/cacheflush.h
@@ -12,6 +12,7 @@
 #define flush_cache_dup_mm(mm)                  do { } while (0)
 #define flush_cache_range(vma, start, end)      do { } while (0)
 #define flush_cache_page(vma, vmaddr, pfn)      do { } while (0)
+#define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 0
 #define flush_dcache_page(page)                 do { } while (0)
 #define flush_dcache_mmap_lock(mapping)         do { } while (0)
 #define flush_dcache_mmap_unlock(mapping)       do { } while (0)
diff --git a/arch/frv/include/asm/cacheflush.h b/arch/frv/include/asm/cacheflush.h
index 432a69e7f3d4..edbac54ae015 100644
--- a/arch/frv/include/asm/cacheflush.h
+++ b/arch/frv/include/asm/cacheflush.h
@@ -47,6 +47,7 @@ static inline void __flush_cache_all(void)
 }
 
 /* dcache/icache coherency... */
+#define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 1
 #ifdef CONFIG_MMU
 extern void flush_dcache_page(struct page *page);
 #else
diff --git a/arch/h8300/include/asm/cacheflush.h b/arch/h8300/include/asm/cacheflush.h
index 5ffdca217b95..4cf2df20c1ce 100644
--- a/arch/h8300/include/asm/cacheflush.h
+++ b/arch/h8300/include/asm/cacheflush.h
@@ -15,6 +15,7 @@
 #define flush_cache_dup_mm(mm)          do { } while (0)
 #define flush_cache_range(vma,a,b)
 #define flush_cache_page(vma,p,pfn)
+#define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 0
 #define flush_dcache_page(page)
 #define flush_dcache_mmap_lock(mapping)
 #define flush_dcache_mmap_unlock(mapping)
diff --git a/arch/ia64/include/asm/cacheflush.h b/arch/ia64/include/asm/cacheflush.h
index c8ce2719fee8..429eefc93ee7 100644
--- a/arch/ia64/include/asm/cacheflush.h
+++ b/arch/ia64/include/asm/cacheflush.h
@@ -25,6 +25,7 @@
 #define flush_cache_vmap(start, end)            do { } while (0)
 #define flush_cache_vunmap(start, end)          do { } while (0)
 
+#define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 1
 #define flush_dcache_page(page)                 \
 do {                                            \
         clear_bit(PG_arch_1, &(page)->flags);   \
diff --git a/arch/m32r/include/asm/cacheflush.h b/arch/m32r/include/asm/cacheflush.h
index 78587c958146..8e8e04516c39 100644
--- a/arch/m32r/include/asm/cacheflush.h
+++ b/arch/m32r/include/asm/cacheflush.h
@@ -12,6 +12,7 @@ extern void _flush_cache_copyback_all(void);
 #define flush_cache_dup_mm(mm)                  do { } while (0)
 #define flush_cache_range(vma, start, end)      do { } while (0)
 #define flush_cache_page(vma, vmaddr, pfn)      do { } while (0)
+#define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 0
 #define flush_dcache_page(page)                 do { } while (0)
 #define flush_dcache_mmap_lock(mapping)         do { } while (0)
 #define flush_dcache_mmap_unlock(mapping)       do { } while (0)
@@ -33,6 +34,7 @@ extern void smp_flush_cache_all(void);
 #define flush_cache_dup_mm(mm)                  do { } while (0)
 #define flush_cache_range(vma, start, end)      do { } while (0)
 #define flush_cache_page(vma, vmaddr, pfn)      do { } while (0)
+#define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 0
 #define flush_dcache_page(page)                 do { } while (0)
 #define flush_dcache_mmap_lock(mapping)         do { } while (0)
 #define flush_dcache_mmap_unlock(mapping)       do { } while (0)
@@ -46,6 +48,7 @@ extern void smp_flush_cache_all(void);
 #define flush_cache_dup_mm(mm)                  do { } while (0)
 #define flush_cache_range(vma, start, end)      do { } while (0)
 #define flush_cache_page(vma, vmaddr, pfn)      do { } while (0)
+#define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 0
 #define flush_dcache_page(page)                 do { } while (0)
 #define flush_dcache_mmap_lock(mapping)         do { } while (0)
 #define flush_dcache_mmap_unlock(mapping)       do { } while (0)
diff --git a/arch/m68k/include/asm/cacheflush_mm.h b/arch/m68k/include/asm/cacheflush_mm.h
index 16bf375fdbe1..73de7c89d8e0 100644
--- a/arch/m68k/include/asm/cacheflush_mm.h
+++ b/arch/m68k/include/asm/cacheflush_mm.h
@@ -128,6 +128,7 @@ static inline void __flush_page_to_ram(void *vaddr)
         }
 }
 
+#define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 1
 #define flush_dcache_page(page)         __flush_page_to_ram(page_address(page))
 #define flush_dcache_mmap_lock(mapping)         do { } while (0)
 #define flush_dcache_mmap_unlock(mapping)       do { } while (0)
diff --git a/arch/m68k/include/asm/cacheflush_no.h b/arch/m68k/include/asm/cacheflush_no.h
index c65f00a94553..89f195656be7 100644
--- a/arch/m68k/include/asm/cacheflush_no.h
+++ b/arch/m68k/include/asm/cacheflush_no.h
@@ -12,6 +12,7 @@
 #define flush_cache_range(vma, start, end)      __flush_cache_all()
 #define flush_cache_page(vma, vmaddr)           do { } while (0)
 #define flush_dcache_range(start,len)           __flush_cache_all()
+#define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 0
 #define flush_dcache_page(page)                 do { } while (0)
 #define flush_dcache_mmap_lock(mapping)         do { } while (0)
 #define flush_dcache_mmap_unlock(mapping)       do { } while (0)
diff --git a/arch/microblaze/include/asm/cacheflush.h b/arch/microblaze/include/asm/cacheflush.h
index f989d6aad648..088076e657b3 100644
--- a/arch/microblaze/include/asm/cacheflush.h
+++ b/arch/microblaze/include/asm/cacheflush.h
@@ -37,6 +37,7 @@
 #define flush_cache_page(vma, vmaddr, pfn)      do { } while (0)
 
 #define flush_dcache_range(start, end)  __invalidate_dcache_range(start, end)
+#define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 0
 #define flush_dcache_page(page)                 do { } while (0)
 #define flush_dcache_mmap_lock(mapping)         do { } while (0)
 #define flush_dcache_mmap_unlock(mapping)       do { } while (0)
diff --git a/arch/mips/include/asm/cacheflush.h b/arch/mips/include/asm/cacheflush.h
index 03b1d69b142f..40bb9fde205f 100644
--- a/arch/mips/include/asm/cacheflush.h
+++ b/arch/mips/include/asm/cacheflush.h
@@ -38,6 +38,7 @@ extern void (*flush_cache_range)(struct vm_area_struct *vma,
 extern void (*flush_cache_page)(struct vm_area_struct *vma, unsigned long page, unsigned long pfn);
 extern void __flush_dcache_page(struct page *page);
 
+#define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 1
 static inline void flush_dcache_page(struct page *page)
 {
         if (cpu_has_dc_aliases || !cpu_has_ic_fills_f_dc)
diff --git a/arch/mn10300/include/asm/cacheflush.h b/arch/mn10300/include/asm/cacheflush.h
index 1a55d61f0d06..29e692f7f030 100644
--- a/arch/mn10300/include/asm/cacheflush.h
+++ b/arch/mn10300/include/asm/cacheflush.h
@@ -26,6 +26,7 @@
 #define flush_cache_page(vma, vmaddr, pfn)      do {} while (0)
 #define flush_cache_vmap(start, end)            do {} while (0)
 #define flush_cache_vunmap(start, end)          do {} while (0)
+#define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 0
 #define flush_dcache_page(page)                 do {} while (0)
 #define flush_dcache_mmap_lock(mapping)         do {} while (0)
 #define flush_dcache_mmap_unlock(mapping)       do {} while (0)
diff --git a/arch/parisc/include/asm/cacheflush.h b/arch/parisc/include/asm/cacheflush.h
index 724395143f26..7a73b615c23d 100644
--- a/arch/parisc/include/asm/cacheflush.h
+++ b/arch/parisc/include/asm/cacheflush.h
@@ -42,6 +42,7 @@ void flush_cache_mm(struct mm_struct *mm);
 #define flush_cache_vmap(start, end)            flush_cache_all()
 #define flush_cache_vunmap(start, end)          flush_cache_all()
 
+#define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 1
 extern void flush_dcache_page(struct page *page);
 
 #define flush_dcache_mmap_lock(mapping) \
diff --git a/arch/powerpc/include/asm/cacheflush.h b/arch/powerpc/include/asm/cacheflush.h
index ba667a383b8c..ab9e402518e8 100644
--- a/arch/powerpc/include/asm/cacheflush.h
+++ b/arch/powerpc/include/asm/cacheflush.h
@@ -25,6 +25,7 @@
 #define flush_cache_vmap(start, end)            do { } while (0)
 #define flush_cache_vunmap(start, end)          do { } while (0)
 
+#define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 1
 extern void flush_dcache_page(struct page *page);
 #define flush_dcache_mmap_lock(mapping)         do { } while (0)
 #define flush_dcache_mmap_unlock(mapping)       do { } while (0)
diff --git a/arch/s390/include/asm/cacheflush.h b/arch/s390/include/asm/cacheflush.h
index 49d5af916d01..405cc97c6249 100644
--- a/arch/s390/include/asm/cacheflush.h
+++ b/arch/s390/include/asm/cacheflush.h
@@ -10,6 +10,7 @@
 #define flush_cache_dup_mm(mm)                  do { } while (0)
 #define flush_cache_range(vma, start, end)      do { } while (0)
 #define flush_cache_page(vma, vmaddr, pfn)      do { } while (0)
+#define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 0
 #define flush_dcache_page(page)                 do { } while (0)
 #define flush_dcache_mmap_lock(mapping)         do { } while (0)
 #define flush_dcache_mmap_unlock(mapping)       do { } while (0)
diff --git a/arch/score/include/asm/cacheflush.h b/arch/score/include/asm/cacheflush.h
index 07cc8fc457cd..caaba24036e3 100644
--- a/arch/score/include/asm/cacheflush.h
+++ b/arch/score/include/asm/cacheflush.h
@@ -16,6 +16,7 @@ extern void flush_icache_range(unsigned long start, unsigned long end);
 extern void flush_dcache_range(unsigned long start, unsigned long end);
 
 #define flush_cache_dup_mm(mm)                  do {} while (0)
+#define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 0
 #define flush_dcache_page(page)                 do {} while (0)
 #define flush_dcache_mmap_lock(mapping)         do {} while (0)
 #define flush_dcache_mmap_unlock(mapping)       do {} while (0)
diff --git a/arch/sh/include/asm/cacheflush.h b/arch/sh/include/asm/cacheflush.h
index c29918f3c819..dda96eb3e7c0 100644
--- a/arch/sh/include/asm/cacheflush.h
+++ b/arch/sh/include/asm/cacheflush.h
@@ -42,6 +42,7 @@ extern void flush_cache_page(struct vm_area_struct *vma,
                                 unsigned long addr, unsigned long pfn);
 extern void flush_cache_range(struct vm_area_struct *vma,
                                  unsigned long start, unsigned long end);
+#define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 1
 extern void flush_dcache_page(struct page *page);
 extern void flush_icache_range(unsigned long start, unsigned long end);
 extern void flush_icache_page(struct vm_area_struct *vma,
diff --git a/arch/sparc/include/asm/cacheflush_32.h b/arch/sparc/include/asm/cacheflush_32.h
index 68ac10910271..2e468773f250 100644
--- a/arch/sparc/include/asm/cacheflush_32.h
+++ b/arch/sparc/include/asm/cacheflush_32.h
@@ -75,6 +75,7 @@ BTFIXUPDEF_CALL(void, flush_sig_insns, struct mm_struct *, unsigned long)
 
 extern void sparc_flush_page_to_ram(struct page *page);
 
+#define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 1
 #define flush_dcache_page(page)                 sparc_flush_page_to_ram(page)
 #define flush_dcache_mmap_lock(mapping)         do { } while (0)
 #define flush_dcache_mmap_unlock(mapping)       do { } while (0)
diff --git a/arch/sparc/include/asm/cacheflush_64.h b/arch/sparc/include/asm/cacheflush_64.h
index c43321729b3b..b95384033e89 100644
--- a/arch/sparc/include/asm/cacheflush_64.h
+++ b/arch/sparc/include/asm/cacheflush_64.h
@@ -37,6 +37,7 @@ extern void flush_dcache_page_all(struct mm_struct *mm, struct page *page);
 #endif
 
 extern void __flush_dcache_range(unsigned long start, unsigned long end);
+#define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 1
 extern void flush_dcache_page(struct page *page);
 
 #define flush_icache_page(vma, pg)      do { } while(0)
diff --git a/arch/x86/include/asm/cacheflush.h b/arch/x86/include/asm/cacheflush.h
index b54f6afe7ec4..9076add593a8 100644
--- a/arch/x86/include/asm/cacheflush.h
+++ b/arch/x86/include/asm/cacheflush.h
@@ -12,6 +12,7 @@ static inline void flush_cache_range(struct vm_area_struct *vma,
                                      unsigned long start, unsigned long end) { }
 static inline void flush_cache_page(struct vm_area_struct *vma,
                                     unsigned long vmaddr, unsigned long pfn) { }
+#define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 0
 static inline void flush_dcache_page(struct page *page) { }
 static inline void flush_dcache_mmap_lock(struct address_space *mapping) { }
 static inline void flush_dcache_mmap_unlock(struct address_space *mapping) { }
diff --git a/arch/xtensa/include/asm/cacheflush.h b/arch/xtensa/include/asm/cacheflush.h
index b7b8fbe47c77..a508f2f73bd7 100644
--- a/arch/xtensa/include/asm/cacheflush.h
+++ b/arch/xtensa/include/asm/cacheflush.h
@@ -101,6 +101,7 @@ static inline void __invalidate_icache_page_alias(unsigned long virt,
 #define flush_cache_vmap(start,end)     flush_cache_all()
 #define flush_cache_vunmap(start,end)   flush_cache_all()
 
+#define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 1
 extern void flush_dcache_page(struct page*);
 extern void flush_cache_range(struct vm_area_struct*, ulong, ulong);
 extern void flush_cache_page(struct vm_area_struct*, unsigned long, unsigned long);