btrfs: replace remaining do_div calls with div_u64 variants

Switch to div_u64_rem that does type checking and has more obvious
semantics than do_div.

Signed-off-by: David Sterba <dsterba@suse.cz>

4 files changed, 20 insertions, 19 deletions

diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index 4ccc3397c644..5840afe5e5f9 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -8670,7 +8670,7 @@ int btrfs_can_relocate(struct btrfs_root *root, u64 bytenr)
                 min_free <<= 1;
         } else if (index == BTRFS_RAID_RAID0) {
                 dev_min = fs_devices->rw_devices;
-                do_div(min_free, dev_min);
+                min_free = div64_u64(min_free, dev_min);
         }
 
         /* We need to do this so that we can look at pending chunks */
diff --git a/fs/btrfs/free-space-cache.c b/fs/btrfs/free-space-cache.c
index 13c9b46d4727..764528a4f6fd 100644
--- a/fs/btrfs/free-space-cache.c
+++ b/fs/btrfs/free-space-cache.c
@@ -1673,7 +1673,7 @@ find_free_space(struct btrfs_free_space_ctl *ctl, u64 *offset, u64 *bytes,
                  */
                 if (*bytes >= align) {
                         tmp = entry->offset - ctl->start + align - 1;
-                        do_div(tmp, align);
+                        tmp = div64_u64(tmp, align);
                         tmp = tmp * align + ctl->start;
                         align_off = tmp - entry->offset;
                 } else {
diff --git a/fs/btrfs/scrub.c b/fs/btrfs/scrub.c
index 293262163daf..c21581e0be7a 100644
--- a/fs/btrfs/scrub.c
+++ b/fs/btrfs/scrub.c
@@ -2328,7 +2328,7 @@ static inline void __scrub_mark_bitmap(struct scrub_parity *sparity,
         }
 
         start -= sparity->logic_start;
-        offset = (int)do_div(start, sparity->stripe_len);
+        start = div_u64_rem(start, sparity->stripe_len, &offset);
         offset /= sectorsize;
         nsectors = (int)len / sectorsize;
 
@@ -2627,7 +2627,7 @@ static int get_raid56_logic_offset(u64 physical, int num,
                 stripe_nr = div_u64(stripe_nr, nr_data_stripes(map));
 
                 /* Work out the disk rotation on this stripe-set */
-                rot = do_div(stripe_nr, map->num_stripes);
+                stripe_nr = div_u64_rem(stripe_nr, map->num_stripes, &rot);
                 /* calculate which stripe this data locates */
                 rot += i;
                 stripe_index = rot % map->num_stripes;
diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index d712c46c0a6b..bf38ed09810a 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -4994,7 +4994,7 @@ static int __btrfs_map_block(struct btrfs_fs_info *fs_info, int rw,
          * stripe_nr counts the total number of stripes we have to stride
          * to get to this block
          */
-        do_div(stripe_nr, stripe_len);
+        stripe_nr = div64_u64(stripe_nr, stripe_len);
 
         stripe_offset = stripe_nr * stripe_len;
         BUG_ON(offset < stripe_offset);
@@ -5010,7 +5010,8 @@ static int __btrfs_map_block(struct btrfs_fs_info *fs_info, int rw,
                 /* allow a write of a full stripe, but make sure we don't
                  * allow straddling of stripes
                  */
-                do_div(raid56_full_stripe_start, full_stripe_len);
+                raid56_full_stripe_start = div64_u64(raid56_full_stripe_start,
+                                full_stripe_len);
                 raid56_full_stripe_start *= full_stripe_len;
         }
 
@@ -5143,7 +5144,8 @@ static int __btrfs_map_block(struct btrfs_fs_info *fs_info, int rw,
                 if (rw & REQ_DISCARD)
                         num_stripes = min_t(u64, map->num_stripes,
                                             stripe_nr_end - stripe_nr_orig);
-                stripe_index = do_div(stripe_nr, map->num_stripes);
+                stripe_nr = div_u64_rem(stripe_nr, map->num_stripes,
+                                &stripe_index);
                 if (!(rw & (REQ_WRITE | REQ_DISCARD | REQ_GET_READ_MIRRORS)))
                         mirror_num = 1;
         } else if (map->type & BTRFS_BLOCK_GROUP_RAID1) {
@@ -5171,7 +5173,7 @@ static int __btrfs_map_block(struct btrfs_fs_info *fs_info, int rw,
         } else if (map->type & BTRFS_BLOCK_GROUP_RAID10) {
                 int factor = map->num_stripes / map->sub_stripes;
 
-                stripe_index = do_div(stripe_nr, factor);
+                stripe_nr = div_u64_rem(stripe_nr, factor, &stripe_index);
                 stripe_index *= map->sub_stripes;
 
                 if (rw & (REQ_WRITE | REQ_GET_READ_MIRRORS))
@@ -5208,32 +5210,32 @@ static int __btrfs_map_block(struct btrfs_fs_info *fs_info, int rw,
                         stripe_index = 0;
                         stripe_offset = 0;
                 } else {
-                        u64 tmp;
-
                         /*
                          * Mirror #0 or #1 means the original data block.
                          * Mirror #2 is RAID5 parity block.
                          * Mirror #3 is RAID6 Q block.
                          */
-                        stripe_index = do_div(stripe_nr, nr_data_stripes(map));
+                        stripe_nr = div_u64_rem(stripe_nr,
+                                        nr_data_stripes(map), &stripe_index);
                         if (mirror_num > 1)
                                 stripe_index = nr_data_stripes(map) +
                                                 mirror_num - 2;
 
                         /* We distribute the parity blocks across stripes */
-                        tmp = stripe_nr + stripe_index;
-                        stripe_index = do_div(tmp, map->num_stripes);
+                        div_u64_rem(stripe_nr + stripe_index, map->num_stripes,
+                                        &stripe_index);
                         if (!(rw & (REQ_WRITE | REQ_DISCARD |
                                     REQ_GET_READ_MIRRORS)) && mirror_num <= 1)
                                 mirror_num = 1;
                 }
         } else {
                 /*
-                 * after this do_div call, stripe_nr is the number of stripes
-                 * on this device we have to walk to find the data, and
-                 * stripe_index is the number of our device in the stripe array
+                 * after this, stripe_nr is the number of stripes on this
+                 * device we have to walk to find the data, and stripe_index is
+                 * the number of our device in the stripe array
                  */
-                stripe_index = do_div(stripe_nr, map->num_stripes);
+                stripe_nr = div_u64_rem(stripe_nr, map->num_stripes,
+                                &stripe_index);
                 mirror_num = stripe_index + 1;
         }
         BUG_ON(stripe_index >= map->num_stripes);
@@ -5268,8 +5270,7 @@ static int __btrfs_map_block(struct btrfs_fs_info *fs_info, int rw,
                                  sizeof(int) * tgtdev_indexes);
 
                 /* Work out the disk rotation on this stripe-set */
-                tmp = stripe_nr;
-                rot = do_div(tmp, num_stripes);
+                div_u64_rem(stripe_nr, num_stripes, &rot);
 
                 /* Fill in the logical address of each stripe */
                 tmp = stripe_nr * nr_data_stripes(map);