Merge branch 'fst-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux...

[cascardo/linux.git] / fs / btrfs / extent_io.c

diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c
index ee40384..66a7551 100644 (file)
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -5558,17 +5558,45 @@ void copy_extent_buffer(struct extent_buffer *dst, struct extent_buffer *src,
        }
 }
 
-/*
- * The extent buffer bitmap operations are done with byte granularity because
- * bitmap items are not guaranteed to be aligned to a word and therefore a
- * single word in a bitmap may straddle two pages in the extent buffer.
- */
-#define BIT_BYTE(nr) ((nr) / BITS_PER_BYTE)
-#define BYTE_MASK ((1 << BITS_PER_BYTE) - 1)
-#define BITMAP_FIRST_BYTE_MASK(start) \
-       ((BYTE_MASK << ((start) & (BITS_PER_BYTE - 1))) & BYTE_MASK)
-#define BITMAP_LAST_BYTE_MASK(nbits) \
-       (BYTE_MASK >> (-(nbits) & (BITS_PER_BYTE - 1)))
+void le_bitmap_set(u8 *map, unsigned int start, int len)
+{
+       u8 *p = map + BIT_BYTE(start);
+       const unsigned int size = start + len;
+       int bits_to_set = BITS_PER_BYTE - (start % BITS_PER_BYTE);
+       u8 mask_to_set = BITMAP_FIRST_BYTE_MASK(start);
+
+       while (len - bits_to_set >= 0) {
+               *p |= mask_to_set;
+               len -= bits_to_set;
+               bits_to_set = BITS_PER_BYTE;
+               mask_to_set = ~(u8)0;
+               p++;
+       }
+       if (len) {
+               mask_to_set &= BITMAP_LAST_BYTE_MASK(size);
+               *p |= mask_to_set;
+       }
+}
+
+void le_bitmap_clear(u8 *map, unsigned int start, int len)
+{
+       u8 *p = map + BIT_BYTE(start);
+       const unsigned int size = start + len;
+       int bits_to_clear = BITS_PER_BYTE - (start % BITS_PER_BYTE);
+       u8 mask_to_clear = BITMAP_FIRST_BYTE_MASK(start);
+
+       while (len - bits_to_clear >= 0) {
+               *p &= ~mask_to_clear;
+               len -= bits_to_clear;
+               bits_to_clear = BITS_PER_BYTE;
+               mask_to_clear = ~(u8)0;
+               p++;
+       }
+       if (len) {
+               mask_to_clear &= BITMAP_LAST_BYTE_MASK(size);
+               *p &= ~mask_to_clear;
+       }
+}
 
 /*
  * eb_bitmap_offset() - calculate the page and offset of the byte containing the
@@ -5612,7 +5640,7 @@ static inline void eb_bitmap_offset(struct extent_buffer *eb,
 int extent_buffer_test_bit(struct extent_buffer *eb, unsigned long start,
                           unsigned long nr)
 {
-       char *kaddr;
+       u8 *kaddr;
        struct page *page;
        unsigned long i;
        size_t offset;
@@ -5634,13 +5662,13 @@ int extent_buffer_test_bit(struct extent_buffer *eb, unsigned long start,
 void extent_buffer_bitmap_set(struct extent_buffer *eb, unsigned long start,
                              unsigned long pos, unsigned long len)
 {
-       char *kaddr;
+       u8 *kaddr;
        struct page *page;
        unsigned long i;
        size_t offset;
        const unsigned int size = pos + len;
        int bits_to_set = BITS_PER_BYTE - (pos % BITS_PER_BYTE);
-       unsigned int mask_to_set = BITMAP_FIRST_BYTE_MASK(pos);
+       u8 mask_to_set = BITMAP_FIRST_BYTE_MASK(pos);
 
        eb_bitmap_offset(eb, start, pos, &i, &offset);
        page = eb->pages[i];
@@ -5651,7 +5679,7 @@ void extent_buffer_bitmap_set(struct extent_buffer *eb, unsigned long start,
                kaddr[offset] |= mask_to_set;
                len -= bits_to_set;
                bits_to_set = BITS_PER_BYTE;
-               mask_to_set = ~0U;
+               mask_to_set = ~(u8)0;
                if (++offset >= PAGE_SIZE && len > 0) {
                        offset = 0;
                        page = eb->pages[++i];
@@ -5676,13 +5704,13 @@ void extent_buffer_bitmap_set(struct extent_buffer *eb, unsigned long start,
 void extent_buffer_bitmap_clear(struct extent_buffer *eb, unsigned long start,
                                unsigned long pos, unsigned long len)
 {
-       char *kaddr;
+       u8 *kaddr;
        struct page *page;
        unsigned long i;
        size_t offset;
        const unsigned int size = pos + len;
        int bits_to_clear = BITS_PER_BYTE - (pos % BITS_PER_BYTE);
-       unsigned int mask_to_clear = BITMAP_FIRST_BYTE_MASK(pos);
+       u8 mask_to_clear = BITMAP_FIRST_BYTE_MASK(pos);
 
        eb_bitmap_offset(eb, start, pos, &i, &offset);
        page = eb->pages[i];
@@ -5693,7 +5721,7 @@ void extent_buffer_bitmap_clear(struct extent_buffer *eb, unsigned long start,
                kaddr[offset] &= ~mask_to_clear;
                len -= bits_to_clear;
                bits_to_clear = BITS_PER_BYTE;
-               mask_to_clear = ~0U;
+               mask_to_clear = ~(u8)0;
                if (++offset >= PAGE_SIZE && len > 0) {
                        offset = 0;
                        page = eb->pages[++i];