From 96a14336bd8fc13cc3db036a5745acdf3bc185f4 Mon Sep 17 00:00:00 2001 From: Nikolay Borisov Date: Tue, 10 Dec 2019 19:57:51 +0200 Subject: [PATCH] btrfs: Move and unexport btrfs_rmap_block It's used only during initial block group reading to map physical address of super block to a list of logical ones. Make it private to block-group.c, add proper kernel doc and ensure it's exported only for tests. Signed-off-by: Nikolay Borisov Reviewed-by: David Sterba Signed-off-by: David Sterba --- fs/btrfs/block-group.c | 86 ++++++++++++++++++++++++++++++++++++++++++ fs/btrfs/block-group.h | 5 +++ fs/btrfs/volumes.c | 69 --------------------------------- fs/btrfs/volumes.h | 2 - 4 files changed, 91 insertions(+), 71 deletions(-) diff --git a/fs/btrfs/block-group.c b/fs/btrfs/block-group.c index 6480976ddc78..00cb40210b53 100644 --- a/fs/btrfs/block-group.c +++ b/fs/btrfs/block-group.c @@ -15,6 +15,7 @@ #include "tree-log.h" #include "delalloc-space.h" #include "discard.h" +#include "raid56.h" /* * Return target flags in extended format or 0 if restripe for this chunk_type @@ -1561,6 +1562,91 @@ static void set_avail_alloc_bits(struct btrfs_fs_info *fs_info, u64 flags) write_sequnlock(&fs_info->profiles_lock); } +/** + * btrfs_rmap_block - Map a physical disk address to a list of logical addresses + * @chunk_start: logical address of block group + * @physical: physical address to map to logical addresses + * @logical: return array of logical addresses which map to @physical + * @naddrs: length of @logical + * @stripe_len: size of IO stripe for the given block group + * + * Maps a particular @physical disk address to a list of @logical addresses. + * Used primarily to exclude those portions of a block group that contain super + * block copies. + */ +EXPORT_FOR_TESTS +int btrfs_rmap_block(struct btrfs_fs_info *fs_info, u64 chunk_start, + u64 physical, u64 **logical, int *naddrs, int *stripe_len) +{ + struct extent_map *em; + struct map_lookup *map; + u64 *buf; + u64 bytenr; + u64 length; + u64 stripe_nr; + u64 rmap_len; + int i, j, nr = 0; + + em = btrfs_get_chunk_map(fs_info, chunk_start, 1); + if (IS_ERR(em)) + return -EIO; + + map = em->map_lookup; + length = em->len; + rmap_len = map->stripe_len; + + if (map->type & BTRFS_BLOCK_GROUP_RAID10) + length = div_u64(length, map->num_stripes / map->sub_stripes); + else if (map->type & BTRFS_BLOCK_GROUP_RAID0) + length = div_u64(length, map->num_stripes); + else if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) { + length = div_u64(length, nr_data_stripes(map)); + rmap_len = map->stripe_len * nr_data_stripes(map); + } + + buf = kcalloc(map->num_stripes, sizeof(u64), GFP_NOFS); + BUG_ON(!buf); /* -ENOMEM */ + + for (i = 0; i < map->num_stripes; i++) { + if (map->stripes[i].physical > physical || + map->stripes[i].physical + length <= physical) + continue; + + stripe_nr = physical - map->stripes[i].physical; + stripe_nr = div64_u64(stripe_nr, map->stripe_len); + + if (map->type & BTRFS_BLOCK_GROUP_RAID10) { + stripe_nr = stripe_nr * map->num_stripes + i; + stripe_nr = div_u64(stripe_nr, map->sub_stripes); + } else if (map->type & BTRFS_BLOCK_GROUP_RAID0) { + stripe_nr = stripe_nr * map->num_stripes + i; + } + /* + * The remaining case would be for RAID56, multiply by + * nr_data_stripes(). Alternatively, just use rmap_len below + * instead of map->stripe_len + */ + + bytenr = chunk_start + stripe_nr * rmap_len; + WARN_ON(nr >= map->num_stripes); + for (j = 0; j < nr; j++) { + if (buf[j] == bytenr) + break; + } + if (j == nr) { + WARN_ON(nr >= map->num_stripes); + buf[nr++] = bytenr; + } + } + + *logical = buf; + *naddrs = nr; + *stripe_len = rmap_len; + + free_extent_map(em); + return 0; +} + static int exclude_super_stripes(struct btrfs_block_group *cache) { struct btrfs_fs_info *fs_info = cache->fs_info; diff --git a/fs/btrfs/block-group.h b/fs/btrfs/block-group.h index 5cf1ea33f284..107bb557ca8d 100644 --- a/fs/btrfs/block-group.h +++ b/fs/btrfs/block-group.h @@ -283,4 +283,9 @@ static inline int btrfs_block_group_done(struct btrfs_block_group *cache) cache->cached == BTRFS_CACHE_ERROR; } +#ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS +int btrfs_rmap_block(struct btrfs_fs_info *fs_info, u64 chunk_start, + u64 physical, u64 **logical, int *naddrs, int *stripe_len); +#endif + #endif /* BTRFS_BLOCK_GROUP_H */ diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c index 9658c53eec7b..ab1b3c35c5eb 100644 --- a/fs/btrfs/volumes.c +++ b/fs/btrfs/volumes.c @@ -6114,75 +6114,6 @@ int btrfs_map_sblock(struct btrfs_fs_info *fs_info, enum btrfs_map_op op, return __btrfs_map_block(fs_info, op, logical, length, bbio_ret, 0, 1); } -int btrfs_rmap_block(struct btrfs_fs_info *fs_info, u64 chunk_start, - u64 physical, u64 **logical, int *naddrs, int *stripe_len) -{ - struct extent_map *em; - struct map_lookup *map; - u64 *buf; - u64 bytenr; - u64 length; - u64 stripe_nr; - u64 rmap_len; - int i, j, nr = 0; - - em = btrfs_get_chunk_map(fs_info, chunk_start, 1); - if (IS_ERR(em)) - return -EIO; - - map = em->map_lookup; - length = em->len; - rmap_len = map->stripe_len; - - if (map->type & BTRFS_BLOCK_GROUP_RAID10) - length = div_u64(length, map->num_stripes / map->sub_stripes); - else if (map->type & BTRFS_BLOCK_GROUP_RAID0) - length = div_u64(length, map->num_stripes); - else if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) { - length = div_u64(length, nr_data_stripes(map)); - rmap_len = map->stripe_len * nr_data_stripes(map); - } - - buf = kcalloc(map->num_stripes, sizeof(u64), GFP_NOFS); - BUG_ON(!buf); /* -ENOMEM */ - - for (i = 0; i < map->num_stripes; i++) { - if (map->stripes[i].physical > physical || - map->stripes[i].physical + length <= physical) - continue; - - stripe_nr = physical - map->stripes[i].physical; - stripe_nr = div64_u64(stripe_nr, map->stripe_len); - - if (map->type & BTRFS_BLOCK_GROUP_RAID10) { - stripe_nr = stripe_nr * map->num_stripes + i; - stripe_nr = div_u64(stripe_nr, map->sub_stripes); - } else if (map->type & BTRFS_BLOCK_GROUP_RAID0) { - stripe_nr = stripe_nr * map->num_stripes + i; - } /* else if RAID[56], multiply by nr_data_stripes(). - * Alternatively, just use rmap_len below instead of - * map->stripe_len */ - - bytenr = chunk_start + stripe_nr * rmap_len; - WARN_ON(nr >= map->num_stripes); - for (j = 0; j < nr; j++) { - if (buf[j] == bytenr) - break; - } - if (j == nr) { - WARN_ON(nr >= map->num_stripes); - buf[nr++] = bytenr; - } - } - - *logical = buf; - *naddrs = nr; - *stripe_len = rmap_len; - - free_extent_map(em); - return 0; -} - static inline void btrfs_end_bbio(struct btrfs_bio *bbio, struct bio *bio) { bio->bi_private = bbio->private; diff --git a/fs/btrfs/volumes.h b/fs/btrfs/volumes.h index 81f21e42b887..9c7d4fe5c39a 100644 --- a/fs/btrfs/volumes.h +++ b/fs/btrfs/volumes.h @@ -415,8 +415,6 @@ int btrfs_map_sblock(struct btrfs_fs_info *fs_info, enum btrfs_map_op op, struct btrfs_bio **bbio_ret); int btrfs_get_io_geometry(struct btrfs_fs_info *fs_info, enum btrfs_map_op op, u64 logical, u64 len, struct btrfs_io_geometry *io_geom); -int btrfs_rmap_block(struct btrfs_fs_info *fs_info, u64 chunk_start, - u64 physical, u64 **logical, int *naddrs, int *stripe_len); int btrfs_read_sys_array(struct btrfs_fs_info *fs_info); int btrfs_read_chunk_tree(struct btrfs_fs_info *fs_info); int btrfs_alloc_chunk(struct btrfs_trans_handle *trans, u64 type);