On Mon, Aug 15, 2011 at 02:52:14PM -0400, Mikulas Patocka wrote: > dm-space-map-disk: improve bit testing Very nice, thanks. btw, you can get rid of WORD_MASK_LOW too: diff --git a/drivers/md/persistent-data/dm-space-map-disk.c b/drivers/md/persistent-data/dm-space-map-disk.c index 8d2c4c2..fbfa6f3 100644 --- a/drivers/md/persistent-data/dm-space-map-disk.c +++ b/drivers/md/persistent-data/dm-space-map-disk.c @@ -69,7 +69,6 @@ void *dm_bitmap_data(struct dm_block *b) return dm_block_data(b) + sizeof(struct disk_bitmap_header); } -#define WORD_MASK_LOW 0x5555555555555555ULL #define WORD_MASK_HIGH 0xAAAAAAAAAAAAAAAAULL static unsigned bitmap_word_used(void *addr, unsigned b) @@ -78,7 +77,7 @@ static unsigned bitmap_word_used(void *addr, unsigned b) __le64 *w_le = words_le + (b >> ENTRIES_SHIFT); uint64_t bits = le64_to_cpu(*w_le); - uint64_t mask = (bits - WORD_MASK_LOW) & WORD_MASK_HIGH; + uint64_t mask = (bits + WORD_MASK_HIGH + 1) & WORD_MASK_HIGH; return !(~bits & mask); } -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel
