btrfs: remove struct btrfs_io_geometry

Now that btrfs_get_io_geometry has a single caller, we can massage it
into a form that is more suitable for that caller and remove the
marshalling into and out of struct btrfs_io_geometry.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David Sterba <dsterba@suse.com>

diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index 3510274ba195a63f45219c402772c829a3c13fad..7823168c08a6aa22466addc1472f0c4f3732529c 100644 (file)
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -6284,91 +6284,42 @@ static bool need_full_stripe(enum btrfs_map_op op)
        return (op == BTRFS_MAP_WRITE || op == BTRFS_MAP_GET_READ_MIRRORS);
 }
 
-/*
- * Calculate the geometry of a particular (address, len) tuple. This
- * information is used to calculate how big a particular bio can get before it
- * straddles a stripe.
- *
- * @fs_info: the filesystem
- * @em:      mapping containing the logical extent
- * @op:      type of operation - write or read
- * @logical: address that we want to figure out the geometry of
- * @io_geom: pointer used to return values
- *
- * Returns < 0 in case a chunk for the given logical address cannot be found,
- * usually shouldn't happen unless @logical is corrupted, 0 otherwise.
- */
-int btrfs_get_io_geometry(struct btrfs_fs_info *fs_info, struct extent_map *em,
-                         enum btrfs_map_op op, u64 logical,
-                         struct btrfs_io_geometry *io_geom)
+static u64 btrfs_max_io_len(struct map_lookup *map, enum btrfs_map_op op,
+                           u64 offset, u64 *stripe_nr, u64 *stripe_offset,
+                           u64 *full_stripe_start)
 {
-       struct map_lookup *map;
-       u64 len;
-       u64 offset;
-       u64 stripe_offset;
-       u64 stripe_nr;
-       u32 stripe_len;
-       u64 raid56_full_stripe_start = (u64)-1;
-       int data_stripes;
+       u32 stripe_len = map->stripe_len;
 
        ASSERT(op != BTRFS_MAP_DISCARD);
 
-       map = em->map_lookup;
-       /* Offset of this logical address in the chunk */
-       offset = logical - em->start;
-       /* Len of a stripe in a chunk */
-       stripe_len = map->stripe_len;
        /*
-        * Stripe_nr is where this block falls in
-        * stripe_offset is the offset of this block in its stripe.
+        * Stripe_nr is the stripe where this block falls.  stripe_offset is
+        * the offset of this block in its stripe.
         */
-       stripe_nr = div64_u64_rem(offset, stripe_len, &stripe_offset);
-       ASSERT(stripe_offset < U32_MAX);
+       *stripe_nr = div64_u64_rem(offset, stripe_len, stripe_offset);
+       ASSERT(*stripe_offset < U32_MAX);
 
-       data_stripes = nr_data_stripes(map);
+       if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) {
+               unsigned long full_stripe_len = stripe_len * nr_data_stripes(map);
 
-       /* Only stripe based profiles needs to check against stripe length. */
-       if (map->type & BTRFS_BLOCK_GROUP_STRIPE_MASK) {
-               u64 max_len = stripe_len - stripe_offset;
+               *full_stripe_start =
+                       div64_u64(offset, full_stripe_len) * full_stripe_len;
 
                /*
-                * In case of raid56, we need to know the stripe aligned start
+                * For writes to RAID56, allow to write a full stripe set, but
+                * no straddling of stripe sets.
                 */
-               if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) {
-                       unsigned long full_stripe_len = stripe_len * data_stripes;
-                       raid56_full_stripe_start = offset;
-
-                       /*
-                        * Allow a write of a full stripe, but make sure we
-                        * don't allow straddling of stripes
-                        */
-                       raid56_full_stripe_start = div64_u64(raid56_full_stripe_start,
-                                       full_stripe_len);
-                       raid56_full_stripe_start *= full_stripe_len;
-
-                       /*
-                        * For writes to RAID[56], allow a full stripeset across
-                        * all disks. For other RAID types and for RAID[56]
-                        * reads, just allow a single stripe (on a single disk).
-                        */
-                       if (op == BTRFS_MAP_WRITE) {
-                               max_len = stripe_len * data_stripes -
-                                         (offset - raid56_full_stripe_start);
-                       }
-               }
-               len = min_t(u64, em->len - offset, max_len);
-       } else {
-               len = em->len - offset;
+               if (op == BTRFS_MAP_WRITE)
+                       return full_stripe_len - (offset - *full_stripe_start);
        }
 
-       io_geom->len = len;
-       io_geom->offset = offset;
-       io_geom->stripe_len = stripe_len;
-       io_geom->stripe_nr = stripe_nr;
-       io_geom->stripe_offset = stripe_offset;
-       io_geom->raid56_stripe_offset = raid56_full_stripe_start;
-
-       return 0;
+       /*
+        * For other RAID types and for RAID56 reads, allow a single stripe (on
+        * a single disk).
+        */
+       if (map->type & BTRFS_BLOCK_GROUP_STRIPE_MASK)
+               return stripe_len - *stripe_offset;
+       return U64_MAX;
 }
 
 static void set_io_stripe(struct btrfs_io_stripe *dst, const struct map_lookup *map,
@@ -6387,6 +6338,7 @@ int __btrfs_map_block(struct btrfs_fs_info *fs_info, enum btrfs_map_op op,
 {
        struct extent_map *em;
        struct map_lookup *map;
+       u64 map_offset;
        u64 stripe_offset;
        u64 stripe_nr;
        u64 stripe_len;
@@ -6405,7 +6357,7 @@ int __btrfs_map_block(struct btrfs_fs_info *fs_info, enum btrfs_map_op op,
        int patch_the_first_stripe_for_dev_replace = 0;
        u64 physical_to_patch_in_first_stripe = 0;
        u64 raid56_full_stripe_start = (u64)-1;
-       struct btrfs_io_geometry geom;
+       u64 max_len;
 
        ASSERT(bioc_ret);
        ASSERT(op != BTRFS_MAP_DISCARD);
@@ -6413,18 +6365,14 @@ int __btrfs_map_block(struct btrfs_fs_info *fs_info, enum btrfs_map_op op,
        em = btrfs_get_chunk_map(fs_info, logical, *length);
        ASSERT(!IS_ERR(em));
 
-       ret = btrfs_get_io_geometry(fs_info, em, op, logical, &geom);
-       if (ret < 0)
-               return ret;
-
        map = em->map_lookup;
-
-       *length = geom.len;
-       stripe_len = geom.stripe_len;
-       stripe_nr = geom.stripe_nr;
-       stripe_offset = geom.stripe_offset;
-       raid56_full_stripe_start = geom.raid56_stripe_offset;
        data_stripes = nr_data_stripes(map);
+       stripe_len = map->stripe_len;
+
+       map_offset = logical - em->start;
+       max_len = btrfs_max_io_len(map, op, map_offset, &stripe_nr,
+                                  &stripe_offset, &raid56_full_stripe_start);
+       *length = min_t(u64, em->len - map_offset, max_len);
 
        down_read(&dev_replace->rwsem);
        dev_replace_is_ongoing = btrfs_dev_replace_is_ongoing(dev_replace);

diff --git a/fs/btrfs/volumes.h b/fs/btrfs/volumes.h
index 6b7a05f6cf823704fc816cccc555cfe636eadba9..7e51f2238f72e626b21944ca8c10fd12926b24fa 100644 (file)
--- a/fs/btrfs/volumes.h
+++ b/fs/btrfs/volumes.h
@@ -53,21 +53,6 @@ enum btrfs_raid_types {
        BTRFS_NR_RAID_TYPES
 };
 
-struct btrfs_io_geometry {
-       /* remaining bytes before crossing a stripe */
-       u64 len;
-       /* offset of logical address in chunk */
-       u64 offset;
-       /* length of single IO stripe */
-       u32 stripe_len;
-       /* offset of address in stripe */
-       u32 stripe_offset;
-       /* number of stripe where address falls */
-       u64 stripe_nr;
-       /* offset of raid56 stripe into the chunk */
-       u64 raid56_stripe_offset;
-};
-
 /*
  * Use sequence counter to get consistent device stat data on
  * 32-bit processors.
@@ -545,9 +530,6 @@ int __btrfs_map_block(struct btrfs_fs_info *fs_info, enum btrfs_map_op op,
 struct btrfs_discard_stripe *btrfs_map_discard(struct btrfs_fs_info *fs_info,
                                               u64 logical, u64 *length_ret,
                                               u32 *num_stripes);
-int btrfs_get_io_geometry(struct btrfs_fs_info *fs_info, struct extent_map *map,
-                         enum btrfs_map_op op, u64 logical,
-                         struct btrfs_io_geometry *io_geom);
 int btrfs_read_sys_array(struct btrfs_fs_info *fs_info);
 int btrfs_read_chunk_tree(struct btrfs_fs_info *fs_info);
 struct btrfs_block_group *btrfs_create_chunk(struct btrfs_trans_handle *trans,