aboutsummaryrefslogtreecommitdiff
path: root/arch
diff options
context:
space:
mode:
authorJohn David Anglin <dave.anglin@bell.net>2014-01-05 21:25:00 -0500
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2014-01-15 15:28:51 -0800
commitd2c62ec3b445d55819b7d96c3d45af97b0678af0 (patch)
treea095540ab2e24d40573cbaf936677dedad9c848f /arch
parente45410185006f748b0d48292550cfad2e37f47a5 (diff)
downloadlinaro-lsk-d2c62ec3b445d55819b7d96c3d45af97b0678af0.tar.gz
parisc: Ensure full cache coherency for kmap/kunmap
commit f8dae00684d678afa13041ef170cecfd1297ed40 upstream. Helge Deller noted a few weeks ago problems with the AIO support on parisc. This change is the result of numerous iterations on how best to deal with this problem. The solution adopted here is to provide full cache coherency in a uniform manner on all parisc systems. This involves calling flush_dcache_page() on kmap operations and flush_kernel_dcache_page() on kunmap operations. As a result, the copy_user_page() and clear_user_page() functions can be removed and the overall code is simpler. The change ensures that both userspace and kernel aliases to a mapped page are invalidated and flushed. This is necessary for the correct operation of PA8800 and PA8900 based systems which do not support inequivalent aliases. With this change, I have observed no cache related issues on c8000 and rp3440. It is now possible for example to do kernel builds with "-j64" on four way systems. On systems using XFS file systems, the patch recently posted by Mikulas Patocka to "fix crash using XFS on loopback" is needed to avoid a hang caused by an uninitialized lock passed to flush_dcache_page() in the page struct. Signed-off-by: John David Anglin <dave.anglin@bell.net> Signed-off-by: Helge Deller <deller@gmx.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'arch')
-rw-r--r--arch/parisc/include/asm/cacheflush.h12
-rw-r--r--arch/parisc/include/asm/page.h5
-rw-r--r--arch/parisc/kernel/cache.c35
3 files changed, 6 insertions, 46 deletions
diff --git a/arch/parisc/include/asm/cacheflush.h b/arch/parisc/include/asm/cacheflush.h
index f0e2784e7cc..2f9b751878b 100644
--- a/arch/parisc/include/asm/cacheflush.h
+++ b/arch/parisc/include/asm/cacheflush.h
@@ -125,42 +125,38 @@ flush_anon_page(struct vm_area_struct *vma, struct page *page, unsigned long vma
void mark_rodata_ro(void);
#endif
-#ifdef CONFIG_PA8X00
-/* Only pa8800, pa8900 needs this */
-
#include <asm/kmap_types.h>
#define ARCH_HAS_KMAP
-void kunmap_parisc(void *addr);
-
static inline void *kmap(struct page *page)
{
might_sleep();
+ flush_dcache_page(page);
return page_address(page);
}
static inline void kunmap(struct page *page)
{
- kunmap_parisc(page_address(page));
+ flush_kernel_dcache_page_addr(page_address(page));
}
static inline void *kmap_atomic(struct page *page)
{
pagefault_disable();
+ flush_dcache_page(page);
return page_address(page);
}
static inline void __kunmap_atomic(void *addr)
{
- kunmap_parisc(addr);
+ flush_kernel_dcache_page_addr(addr);
pagefault_enable();
}
#define kmap_atomic_prot(page, prot) kmap_atomic(page)
#define kmap_atomic_pfn(pfn) kmap_atomic(pfn_to_page(pfn))
#define kmap_atomic_to_page(ptr) virt_to_page(ptr)
-#endif
#endif /* _PARISC_CACHEFLUSH_H */
diff --git a/arch/parisc/include/asm/page.h b/arch/parisc/include/asm/page.h
index b7adb2ac049..c53fc63149e 100644
--- a/arch/parisc/include/asm/page.h
+++ b/arch/parisc/include/asm/page.h
@@ -28,9 +28,8 @@ struct page;
void clear_page_asm(void *page);
void copy_page_asm(void *to, void *from);
-void clear_user_page(void *vto, unsigned long vaddr, struct page *pg);
-void copy_user_page(void *vto, void *vfrom, unsigned long vaddr,
- struct page *pg);
+#define clear_user_page(vto, vaddr, page) clear_page_asm(vto)
+#define copy_user_page(vto, vfrom, vaddr, page) copy_page_asm(vto, vfrom)
/* #define CONFIG_PARISC_TMPALIAS */
diff --git a/arch/parisc/kernel/cache.c b/arch/parisc/kernel/cache.c
index c035673209f..a72545554a3 100644
--- a/arch/parisc/kernel/cache.c
+++ b/arch/parisc/kernel/cache.c
@@ -388,41 +388,6 @@ void flush_kernel_dcache_page_addr(void *addr)
}
EXPORT_SYMBOL(flush_kernel_dcache_page_addr);
-void clear_user_page(void *vto, unsigned long vaddr, struct page *page)
-{
- clear_page_asm(vto);
- if (!parisc_requires_coherency())
- flush_kernel_dcache_page_asm(vto);
-}
-EXPORT_SYMBOL(clear_user_page);
-
-void copy_user_page(void *vto, void *vfrom, unsigned long vaddr,
- struct page *pg)
-{
- /* Copy using kernel mapping. No coherency is needed
- (all in kmap/kunmap) on machines that don't support
- non-equivalent aliasing. However, the `from' page
- needs to be flushed before it can be accessed through
- the kernel mapping. */
- preempt_disable();
- flush_dcache_page_asm(__pa(vfrom), vaddr);
- preempt_enable();
- copy_page_asm(vto, vfrom);
- if (!parisc_requires_coherency())
- flush_kernel_dcache_page_asm(vto);
-}
-EXPORT_SYMBOL(copy_user_page);
-
-#ifdef CONFIG_PA8X00
-
-void kunmap_parisc(void *addr)
-{
- if (parisc_requires_coherency())
- flush_kernel_dcache_page_addr(addr);
-}
-EXPORT_SYMBOL(kunmap_parisc);
-#endif
-
void purge_tlb_entries(struct mm_struct *mm, unsigned long addr)
{
unsigned long flags;