diff options
| -rw-r--r-- | fs/logfs/logfs.h | 1 | ||||
| -rw-r--r-- | fs/logfs/super.c | 22 | ||||
| -rw-r--r-- | include/linux/string.h | 1 | ||||
| -rw-r--r-- | lib/string.c | 54 | ||||
| -rw-r--r-- | mm/slub.c | 47 |
5 files changed, 57 insertions, 68 deletions
diff --git a/fs/logfs/logfs.h b/fs/logfs/logfs.h index f22d108bfa5d..398ecff6e548 100644 --- a/fs/logfs/logfs.h +++ b/fs/logfs/logfs.h @@ -618,7 +618,6 @@ static inline int logfs_buf_recover(struct logfs_area *area, u64 ofs, struct page *emergency_read_begin(struct address_space *mapping, pgoff_t index); void emergency_read_end(struct page *page); void logfs_crash_dump(struct super_block *sb); -void *memchr_inv(const void *s, int c, size_t n); int logfs_statfs(struct dentry *dentry, struct kstatfs *stats); int logfs_check_ds(struct logfs_disk_super *ds); int logfs_write_sb(struct super_block *sb); diff --git a/fs/logfs/super.c b/fs/logfs/super.c index ce03a182c771..f2697e4df109 100644 --- a/fs/logfs/super.c +++ b/fs/logfs/super.c @@ -91,28 +91,6 @@ void logfs_crash_dump(struct super_block *sb) } /* - * TODO: move to lib/string.c - */ -/** - * memchr_inv - Find a character in an area of memory. - * @s: The memory area - * @c: The byte to search for - * @n: The size of the area. - * - * returns the address of the first character other than @c, or %NULL - * if the whole buffer contains just @c. - */ -void *memchr_inv(const void *s, int c, size_t n) -{ - const unsigned char *p = s; - while (n-- != 0) - if ((unsigned char)c != *p++) - return (void *)(p - 1); - - return NULL; -} - -/* * FIXME: There should be a reserve for root, similar to ext2. */ int logfs_statfs(struct dentry *dentry, struct kstatfs *stats) diff --git a/include/linux/string.h b/include/linux/string.h index a176db2f2c85..e033564f10ba 100644 --- a/include/linux/string.h +++ b/include/linux/string.h @@ -114,6 +114,7 @@ extern int memcmp(const void *,const void *,__kernel_size_t); #ifndef __HAVE_ARCH_MEMCHR extern void * memchr(const void *,int,__kernel_size_t); #endif +void *memchr_inv(const void *s, int c, size_t n); extern char *kstrdup(const char *s, gfp_t gfp); extern char *kstrndup(const char *s, size_t len, gfp_t gfp); diff --git a/lib/string.c b/lib/string.c index 01fad9b203e1..11df54325fb8 100644 --- a/lib/string.c +++ b/lib/string.c @@ -756,3 +756,57 @@ void *memchr(const void *s, int c, size_t n) } EXPORT_SYMBOL(memchr); #endif + +static void *check_bytes8(const u8 *start, u8 value, unsigned int bytes) +{ + while (bytes) { + if (*start != value) + return (void *)start; + start++; + bytes--; + } + return NULL; +} + +/** + * memchr_inv - Find an unmatching character in an area of memory. + * @start: The memory area + * @c: Find a character other than c + * @bytes: The size of the area. + * + * returns the address of the first character other than @c, or %NULL + * if the whole buffer contains just @c. + */ +void *memchr_inv(const void *start, int c, size_t bytes) +{ + u8 value = c; + u64 value64; + unsigned int words, prefix; + + if (bytes <= 16) + return check_bytes8(start, value, bytes); + + value64 = value | value << 8 | value << 16 | value << 24; + value64 = (value64 & 0xffffffff) | value64 << 32; + prefix = 8 - ((unsigned long)start) % 8; + + if (prefix) { + u8 *r = check_bytes8(start, value, prefix); + if (r) + return r; + start += prefix; + bytes -= prefix; + } + + words = bytes / 8; + + while (words) { + if (*(u64 *)start != value64) + return check_bytes8(start, value, 8); + start += 8; + words--; + } + + return check_bytes8(start, value, bytes % 8); +} +EXPORT_SYMBOL(memchr_inv); diff --git a/mm/slub.c b/mm/slub.c index 95215aa6a75e..7d2a996c307e 100644 --- a/mm/slub.c +++ b/mm/slub.c @@ -655,49 +655,6 @@ static void init_object(struct kmem_cache *s, void *object, u8 val) memset(p + s->objsize, val, s->inuse - s->objsize); } -static u8 *check_bytes8(u8 *start, u8 value, unsigned int bytes) -{ - while (bytes) { - if (*start != value) - return start; - start++; - bytes--; - } - return NULL; -} - -static u8 *check_bytes(u8 *start, u8 value, unsigned int bytes) -{ - u64 value64; - unsigned int words, prefix; - - if (bytes <= 16) - return check_bytes8(start, value, bytes); - - value64 = value | value << 8 | value << 16 | value << 24; - value64 = (value64 & 0xffffffff) | value64 << 32; - prefix = 8 - ((unsigned long)start) % 8; - - if (prefix) { - u8 *r = check_bytes8(start, value, prefix); - if (r) - return r; - start += prefix; - bytes -= prefix; - } - - words = bytes / 8; - - while (words) { - if (*(u64 *)start != value64) - return check_bytes8(start, value, 8); - start += 8; - words--; - } - - return check_bytes8(start, value, bytes % 8); -} - static void restore_bytes(struct kmem_cache *s, char *message, u8 data, void *from, void *to) { @@ -712,7 +669,7 @@ static int check_bytes_and_report(struct kmem_cache *s, struct page *page, u8 *fault; u8 *end; - fault = check_bytes(start, value, bytes); + fault = memchr_inv(start, value, bytes); if (!fault) return 1; @@ -805,7 +762,7 @@ static int slab_pad_check(struct kmem_cache *s, struct page *page) if (!remainder) return 1; - fault = check_bytes(end - remainder, POISON_INUSE, remainder); + fault = memchr_inv(end - remainder, POISON_INUSE, remainder); if (!fault) return 1; while (end > fault && end[-1] == POISON_INUSE) |