dm verity: use __ffs and __fls

This patch changes ffs() to __ffs() and fls() to __fls() which don't add
one to the result.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>

1 files changed, 4 insertions, 4 deletions

diff --git a/drivers/md/dm-verity.c b/drivers/md/dm-verity.c
index 9804da16a476..4b7941db3aff 100644
--- a/drivers/md/dm-verity.c
+++ b/drivers/md/dm-verity.c
@@ -451,7 +451,7 @@ static void verity_prefetch_io(struct work_struct *work)
                                 goto no_prefetch_cluster;
 
                         if (unlikely(cluster & (cluster - 1)))
-                                cluster = 1 << (fls(cluster) - 1);
+                                cluster = 1 << __fls(cluster);
 
                         hash_block_start &= ~(sector_t)(cluster - 1);
                         hash_block_end |= cluster - 1;
@@ -723,7 +723,7 @@ static int verity_ctr(struct dm_target *ti, unsigned argc, char **argv)
                 r = -EINVAL;
                 goto bad;
         }
-        v->data_dev_block_bits = ffs(num) - 1;
+        v->data_dev_block_bits = __ffs(num);
 
         if (sscanf(argv[4], "%u%c", &num, &dummy) != 1 ||
             !num || (num & (num - 1)) ||
@@ -733,7 +733,7 @@ static int verity_ctr(struct dm_target *ti, unsigned argc, char **argv)
                 r = -EINVAL;
                 goto bad;
         }
-        v->hash_dev_block_bits = ffs(num) - 1;
+        v->hash_dev_block_bits = __ffs(num);
 
         if (sscanf(argv[5], "%llu%c", &num_ll, &dummy) != 1 ||
             (sector_t)(num_ll << (v->data_dev_block_bits - SECTOR_SHIFT))
@@ -812,7 +812,7 @@ static int verity_ctr(struct dm_target *ti, unsigned argc, char **argv)
         }
 
         v->hash_per_block_bits =
-                fls((1 << v->hash_dev_block_bits) / v->digest_size) - 1;
+                __fls((1 << v->hash_dev_block_bits) / v->digest_size);
 
         v->levels = 0;
         if (v->data_blocks)