summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorLinus Torvalds <torvalds@linux-foundation.org>2010-02-26 17:05:10 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2010-02-26 17:05:10 -0800
commitf24407d2bde27a4eb75ce5e52069bf4f1ba0e8a5 (patch)
tree6ad6dbc0b3d394435615b5e53b7d2ab3bde4c354
parent654451748b779b28077d9058442d0f354251870d (diff)
parent73c77e2ccc14413c232c3e0b3aa43a0c4b72ec70 (diff)
downloadconfigs-f24407d2bde27a4eb75ce5e52069bf4f1ba0e8a5.tar.gz
Merge git://git.kernel.org/pub/scm/linux/kernel/git/jejb/xfs-vipt
* git://git.kernel.org/pub/scm/linux/kernel/git/jejb/xfs-vipt: xfs: fix xfs to work with Virtually Indexed architectures sh: add mm API for DMA to vmalloc/vmap areas arm: add mm API for DMA to vmalloc/vmap areas parisc: add mm API for DMA to vmalloc/vmap areas mm: add coherence API for DMA to vmalloc/vmap areas
-rw-r--r--Documentation/cachetlb.txt24
-rw-r--r--arch/arm/include/asm/cacheflush.h10
-rw-r--r--arch/parisc/include/asm/cacheflush.h12
-rw-r--r--arch/sh/include/asm/cacheflush.h8
-rw-r--r--fs/xfs/linux-2.6/xfs_buf.c30
-rw-r--r--include/linux/highmem.h6
6 files changed, 89 insertions, 1 deletions
diff --git a/Documentation/cachetlb.txt b/Documentation/cachetlb.txt
index da42ab414c4..b231414bb8b 100644
--- a/Documentation/cachetlb.txt
+++ b/Documentation/cachetlb.txt
@@ -377,3 +377,27 @@ maps this page at its virtual address.
All the functionality of flush_icache_page can be implemented in
flush_dcache_page and update_mmu_cache. In 2.7 the hope is to
remove this interface completely.
+
+The final category of APIs is for I/O to deliberately aliased address
+ranges inside the kernel. Such aliases are set up by use of the
+vmap/vmalloc API. Since kernel I/O goes via physical pages, the I/O
+subsystem assumes that the user mapping and kernel offset mapping are
+the only aliases. This isn't true for vmap aliases, so anything in
+the kernel trying to do I/O to vmap areas must manually manage
+coherency. It must do this by flushing the vmap range before doing
+I/O and invalidating it after the I/O returns.
+
+ void flush_kernel_vmap_range(void *vaddr, int size)
+ flushes the kernel cache for a given virtual address range in
+ the vmap area. This is to make sure that any data the kernel
+ modified in the vmap range is made visible to the physical
+ page. The design is to make this area safe to perform I/O on.
+ Note that this API does *not* also flush the offset map alias
+ of the area.
+
+ void invalidate_kernel_vmap_range(void *vaddr, int size) invalidates
+ the cache for a given virtual address range in the vmap area
+ which prevents the processor from making the cache stale by
+ speculatively reading data while the I/O was occurring to the
+ physical pages. This is only necessary for data reads into the
+ vmap area.
diff --git a/arch/arm/include/asm/cacheflush.h b/arch/arm/include/asm/cacheflush.h
index 8113bb5fb66..5fe4a2ad7fa 100644
--- a/arch/arm/include/asm/cacheflush.h
+++ b/arch/arm/include/asm/cacheflush.h
@@ -447,6 +447,16 @@ static inline void __flush_icache_all(void)
: "r" (0));
#endif
}
+static inline void flush_kernel_vmap_range(void *addr, int size)
+{
+ if ((cache_is_vivt() || cache_is_vipt_aliasing()))
+ __cpuc_flush_dcache_area(addr, (size_t)size);
+}
+static inline void invalidate_kernel_vmap_range(void *addr, int size)
+{
+ if ((cache_is_vivt() || cache_is_vipt_aliasing()))
+ __cpuc_flush_dcache_area(addr, (size_t)size);
+}
#define ARCH_HAS_FLUSH_ANON_PAGE
static inline void flush_anon_page(struct vm_area_struct *vma,
diff --git a/arch/parisc/include/asm/cacheflush.h b/arch/parisc/include/asm/cacheflush.h
index 7a73b615c23..477277739da 100644
--- a/arch/parisc/include/asm/cacheflush.h
+++ b/arch/parisc/include/asm/cacheflush.h
@@ -38,6 +38,18 @@ void flush_cache_mm(struct mm_struct *mm);
#define flush_kernel_dcache_range(start,size) \
flush_kernel_dcache_range_asm((start), (start)+(size));
+/* vmap range flushes and invalidates. Architecturally, we don't need
+ * the invalidate, because the CPU should refuse to speculate once an
+ * area has been flushed, so invalidate is left empty */
+static inline void flush_kernel_vmap_range(void *vaddr, int size)
+{
+ unsigned long start = (unsigned long)vaddr;
+
+ flush_kernel_dcache_range_asm(start, start + size);
+}
+static inline void invalidate_kernel_vmap_range(void *vaddr, int size)
+{
+}
#define flush_cache_vmap(start, end) flush_cache_all()
#define flush_cache_vunmap(start, end) flush_cache_all()
diff --git a/arch/sh/include/asm/cacheflush.h b/arch/sh/include/asm/cacheflush.h
index dda96eb3e7c..da3ebec921a 100644
--- a/arch/sh/include/asm/cacheflush.h
+++ b/arch/sh/include/asm/cacheflush.h
@@ -63,6 +63,14 @@ static inline void flush_anon_page(struct vm_area_struct *vma,
if (boot_cpu_data.dcache.n_aliases && PageAnon(page))
__flush_anon_page(page, vmaddr);
}
+static inline void flush_kernel_vmap_range(void *addr, int size)
+{
+ __flush_wback_region(addr, size);
+}
+static inline void invalidate_kernel_vmap_range(void *addr, int size)
+{
+ __flush_invalidate_region(addr, size);
+}
#define ARCH_HAS_FLUSH_KERNEL_DCACHE_PAGE
static inline void flush_kernel_dcache_page(struct page *page)
diff --git a/fs/xfs/linux-2.6/xfs_buf.c b/fs/xfs/linux-2.6/xfs_buf.c
index 77b8be81c76..6f3ebb634b8 100644
--- a/fs/xfs/linux-2.6/xfs_buf.c
+++ b/fs/xfs/linux-2.6/xfs_buf.c
@@ -76,6 +76,27 @@ struct workqueue_struct *xfsconvertd_workqueue;
#define xfs_buf_deallocate(bp) \
kmem_zone_free(xfs_buf_zone, (bp));
+static inline int
+xfs_buf_is_vmapped(
+ struct xfs_buf *bp)
+{
+ /*
+ * Return true if the buffer is vmapped.
+ *
+ * The XBF_MAPPED flag is set if the buffer should be mapped, but the
+ * code is clever enough to know it doesn't have to map a single page,
+ * so the check has to be both for XBF_MAPPED and bp->b_page_count > 1.
+ */
+ return (bp->b_flags & XBF_MAPPED) && bp->b_page_count > 1;
+}
+
+static inline int
+xfs_buf_vmap_len(
+ struct xfs_buf *bp)
+{
+ return (bp->b_page_count * PAGE_SIZE) - bp->b_offset;
+}
+
/*
* Page Region interfaces.
*
@@ -314,7 +335,7 @@ xfs_buf_free(
if (bp->b_flags & (_XBF_PAGE_CACHE|_XBF_PAGES)) {
uint i;
- if ((bp->b_flags & XBF_MAPPED) && (bp->b_page_count > 1))
+ if (xfs_buf_is_vmapped(bp))
free_address(bp->b_addr - bp->b_offset);
for (i = 0; i < bp->b_page_count; i++) {
@@ -1107,6 +1128,9 @@ xfs_buf_bio_end_io(
xfs_buf_ioerror(bp, -error);
+ if (!error && xfs_buf_is_vmapped(bp) && (bp->b_flags & XBF_READ))
+ invalidate_kernel_vmap_range(bp->b_addr, xfs_buf_vmap_len(bp));
+
do {
struct page *page = bvec->bv_page;
@@ -1216,6 +1240,10 @@ next_chunk:
submit_io:
if (likely(bio->bi_size)) {
+ if (xfs_buf_is_vmapped(bp)) {
+ flush_kernel_vmap_range(bp->b_addr,
+ xfs_buf_vmap_len(bp));
+ }
submit_bio(rw, bio);
if (size)
goto next_chunk;
diff --git a/include/linux/highmem.h b/include/linux/highmem.h
index ab2cc20e21a..74152c08ad0 100644
--- a/include/linux/highmem.h
+++ b/include/linux/highmem.h
@@ -17,6 +17,12 @@ static inline void flush_anon_page(struct vm_area_struct *vma, struct page *page
static inline void flush_kernel_dcache_page(struct page *page)
{
}
+static inline void flush_kernel_vmap_range(void *vaddr, int size)
+{
+}
+static inline void invalidate_kernel_vmap_range(void *vaddr, int size)
+{
+}
#endif
#include <asm/kmap_types.h>