Btrfs: create a helper for getting chunk map

We have similar code here and there, this merges them into a helper.

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>

diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c
index 174ffffd6d97c2170526e4966eee0fa7effb9f44..77bd016ba18bf9dafa216ce277a6b6d4d90d213f 100644 (file)
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -2004,14 +2004,13 @@ int repair_io_failure(struct btrfs_inode *inode, u64 start, u64 length,
        u64 map_length = 0;
        u64 sector;
        struct btrfs_bio *bbio = NULL;
-       struct btrfs_mapping_tree *map_tree = &fs_info->mapping_tree;
        int ret;
 
        ASSERT(!(fs_info->sb->s_flags & MS_RDONLY));
        BUG_ON(!mirror_num);
 
        /* we can't repair anything in raid56 yet */
-       if (btrfs_is_parity_mirror(map_tree, logical, length, mirror_num))
+       if (btrfs_is_parity_mirror(fs_info, logical, length, mirror_num))
                return 0;
 
        bio = btrfs_io_bio_alloc(GFP_NOFS, 1);

diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index dce59fb59b0c274856719474f52edf3932ce22d6..122201897bee4d23e1b4183800033033a0bbde69 100644 (file)
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -2795,10 +2795,38 @@ static int btrfs_del_sys_chunk(struct btrfs_fs_info *fs_info,
        return ret;
 }
 
+static struct extent_map *get_chunk_map(struct btrfs_fs_info *fs_info,
+                                       u64 logical, u64 length)
+{
+       struct extent_map_tree *em_tree;
+       struct extent_map *em;
+
+       em_tree = &fs_info->mapping_tree.map_tree;
+       read_lock(&em_tree->lock);
+       em = lookup_extent_mapping(em_tree, logical, length);
+       read_unlock(&em_tree->lock);
+
+       if (!em) {
+               btrfs_crit(fs_info, "unable to find logical %llu length %llu",
+                          logical, length);
+               return ERR_PTR(-EINVAL);
+       }
+
+       if (em->start > logical || em->start + em->len < logical) {
+               btrfs_crit(fs_info,
+                          "found a bad mapping, wanted %llu-%llu, found %llu-%llu",
+                          logical, length, em->start, em->start + em->len);
+               free_extent_map(em);
+               return ERR_PTR(-EINVAL);
+       }
+
+       /* callers are responsible for dropping em's ref. */
+       return em;
+}
+
 int btrfs_remove_chunk(struct btrfs_trans_handle *trans,
                       struct btrfs_fs_info *fs_info, u64 chunk_offset)
 {
-       struct extent_map_tree *em_tree;
        struct extent_map *em;
        struct map_lookup *map;
        u64 dev_extent_len = 0;
@@ -2806,23 +2834,15 @@ int btrfs_remove_chunk(struct btrfs_trans_handle *trans,
        int i, ret = 0;
        struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
 
-       em_tree = &fs_info->mapping_tree.map_tree;
-
-       read_lock(&em_tree->lock);
-       em = lookup_extent_mapping(em_tree, chunk_offset, 1);
-       read_unlock(&em_tree->lock);
-
-       if (!em || em->start > chunk_offset ||
-           em->start + em->len < chunk_offset) {
+       em = get_chunk_map(fs_info, chunk_offset, 1);
+       if (IS_ERR(em)) {
                /*
                 * This is a logic error, but we don't want to just rely on the
                 * user having built with ASSERT enabled, so if ASSERT doesn't
                 * do anything we still error out.
                 */
                ASSERT(0);
-               if (em)
-                       free_extent_map(em);
-               return -EINVAL;
+               return PTR_ERR(em);
        }
        map = em->map_lookup;
        mutex_lock(&fs_info->chunk_mutex);
@@ -4894,7 +4914,6 @@ int btrfs_finish_chunk_alloc(struct btrfs_trans_handle *trans,
        struct btrfs_device *device;
        struct btrfs_chunk *chunk;
        struct btrfs_stripe *stripe;
-       struct extent_map_tree *em_tree;
        struct extent_map *em;
        struct map_lookup *map;
        size_t item_size;
@@ -4903,24 +4922,9 @@ int btrfs_finish_chunk_alloc(struct btrfs_trans_handle *trans,
        int i = 0;
        int ret = 0;
 
-       em_tree = &fs_info->mapping_tree.map_tree;
-       read_lock(&em_tree->lock);
-       em = lookup_extent_mapping(em_tree, chunk_offset, chunk_size);
-       read_unlock(&em_tree->lock);
-
-       if (!em) {
-               btrfs_crit(fs_info, "unable to find logical %Lu len %Lu",
-                          chunk_offset, chunk_size);
-               return -EINVAL;
-       }
-
-       if (em->start != chunk_offset || em->len != chunk_size) {
-               btrfs_crit(fs_info,
-                          "found a bad mapping, wanted %Lu-%Lu, found %Lu-%Lu",
-                           chunk_offset, chunk_size, em->start, em->len);
-               free_extent_map(em);
-               return -EINVAL;
-       }
+       em = get_chunk_map(fs_info, chunk_offset, chunk_size);
+       if (IS_ERR(em))
+               return PTR_ERR(em);
 
        map = em->map_lookup;
        item_size = btrfs_chunk_item_size(map->num_stripes);
@@ -5061,15 +5065,12 @@ int btrfs_chunk_readonly(struct btrfs_fs_info *fs_info, u64 chunk_offset)
 {
        struct extent_map *em;
        struct map_lookup *map;
-       struct btrfs_mapping_tree *map_tree = &fs_info->mapping_tree;
        int readonly = 0;
        int miss_ndevs = 0;
        int i;
 
-       read_lock(&map_tree->map_tree.lock);
-       em = lookup_extent_mapping(&map_tree->map_tree, chunk_offset, 1);
-       read_unlock(&map_tree->map_tree.lock);
-       if (!em)
+       em = get_chunk_map(fs_info, chunk_offset, 1);
+       if (IS_ERR(em))
                return 1;
 
        map = em->map_lookup;
@@ -5123,34 +5124,19 @@ void btrfs_mapping_tree_free(struct btrfs_mapping_tree *tree)
 
 int btrfs_num_copies(struct btrfs_fs_info *fs_info, u64 logical, u64 len)
 {
-       struct btrfs_mapping_tree *map_tree = &fs_info->mapping_tree;
        struct extent_map *em;
        struct map_lookup *map;
-       struct extent_map_tree *em_tree = &map_tree->map_tree;
        int ret;
 
-       read_lock(&em_tree->lock);
-       em = lookup_extent_mapping(em_tree, logical, len);
-       read_unlock(&em_tree->lock);
-
-       /*
-        * We could return errors for these cases, but that could get ugly and
-        * we'd probably do the same thing which is just not do anything else
-        * and exit, so return 1 so the callers don't try to use other copies.
-        */
-       if (!em) {
-               btrfs_crit(fs_info, "No mapping for %Lu-%Lu", logical,
-                           logical+len);
-               return 1;
-       }
-
-       if (em->start > logical || em->start + em->len < logical) {
-               btrfs_crit(fs_info, "Invalid mapping for %Lu-%Lu, got %Lu-%Lu",
-                          logical, logical+len, em->start,
-                          em->start + em->len);
-               free_extent_map(em);
+       em = get_chunk_map(fs_info, logical, len);
+       if (IS_ERR(em))
+               /*
+                * We could return errors for these cases, but that could get
+                * ugly and we'd probably do the same thing which is just not do
+                * anything else and exit, so return 1 so the callers don't try
+                * to use other copies.
+                */
                return 1;
-       }
 
        map = em->map_lookup;
        if (map->type & (BTRFS_BLOCK_GROUP_DUP | BTRFS_BLOCK_GROUP_RAID1))
@@ -5179,15 +5165,11 @@ unsigned long btrfs_full_stripe_len(struct btrfs_fs_info *fs_info,
 {
        struct extent_map *em;
        struct map_lookup *map;
-       struct extent_map_tree *em_tree = &map_tree->map_tree;
        unsigned long len = fs_info->sectorsize;
 
-       read_lock(&em_tree->lock);
-       em = lookup_extent_mapping(em_tree, logical, len);
-       read_unlock(&em_tree->lock);
-       BUG_ON(!em);
+       em = get_chunk_map(fs_info, logical, len);
+       BUG_ON(IS_ERR(em));
 
-       BUG_ON(em->start > logical || em->start + em->len < logical);
        map = em->map_lookup;
        if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK)
                len = map->stripe_len * nr_data_stripes(map);
@@ -5195,20 +5177,16 @@ unsigned long btrfs_full_stripe_len(struct btrfs_fs_info *fs_info,
        return len;
 }
 
-int btrfs_is_parity_mirror(struct btrfs_mapping_tree *map_tree,
+int btrfs_is_parity_mirror(struct btrfs_fs_info *fs_info,
                           u64 logical, u64 len, int mirror_num)
 {
        struct extent_map *em;
        struct map_lookup *map;
-       struct extent_map_tree *em_tree = &map_tree->map_tree;
        int ret = 0;
 
-       read_lock(&em_tree->lock);
-       em = lookup_extent_mapping(em_tree, logical, len);
-       read_unlock(&em_tree->lock);
-       BUG_ON(!em);
+       em = get_chunk_map(fs_info, logical, len);
+       BUG_ON(IS_ERR(em));
 
-       BUG_ON(em->start > logical || em->start + em->len < logical);
        map = em->map_lookup;
        if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK)
                ret = 1;
@@ -5328,8 +5306,6 @@ static int __btrfs_map_block(struct btrfs_fs_info *fs_info,
 {
        struct extent_map *em;
        struct map_lookup *map;
-       struct btrfs_mapping_tree *map_tree = &fs_info->mapping_tree;
-       struct extent_map_tree *em_tree = &map_tree->map_tree;
        u64 offset;
        u64 stripe_offset;
        u64 stripe_end_offset;
@@ -5351,23 +5327,9 @@ static int __btrfs_map_block(struct btrfs_fs_info *fs_info,
        u64 physical_to_patch_in_first_stripe = 0;
        u64 raid56_full_stripe_start = (u64)-1;
 
-       read_lock(&em_tree->lock);
-       em = lookup_extent_mapping(em_tree, logical, *length);
-       read_unlock(&em_tree->lock);
-
-       if (!em) {
-               btrfs_crit(fs_info, "unable to find logical %llu len %llu",
-                       logical, *length);
-               return -EINVAL;
-       }
-
-       if (em->start > logical || em->start + em->len < logical) {
-               btrfs_crit(fs_info,
-                          "found a bad mapping, wanted %Lu, found %Lu-%Lu",
-                          logical, em->start, em->start + em->len);
-               free_extent_map(em);
-               return -EINVAL;
-       }
+       em = get_chunk_map(fs_info, logical, *length);
+       if (IS_ERR(em))
+               return PTR_ERR(em);
 
        map = em->map_lookup;
        offset = logical - em->start;
@@ -5903,8 +5865,6 @@ int btrfs_rmap_block(struct btrfs_fs_info *fs_info,
                     u64 chunk_start, u64 physical, u64 devid,
                     u64 **logical, int *naddrs, int *stripe_len)
 {
-       struct btrfs_mapping_tree *map_tree = &fs_info->mapping_tree;
-       struct extent_map_tree *em_tree = &map_tree->map_tree;
        struct extent_map *em;
        struct map_lookup *map;
        u64 *buf;
@@ -5914,24 +5874,11 @@ int btrfs_rmap_block(struct btrfs_fs_info *fs_info,
        u64 rmap_len;
        int i, j, nr = 0;
 
-       read_lock(&em_tree->lock);
-       em = lookup_extent_mapping(em_tree, chunk_start, 1);
-       read_unlock(&em_tree->lock);
-
-       if (!em) {
-               btrfs_err(fs_info, "couldn't find em for chunk %Lu",
-                       chunk_start);
+       em = get_chunk_map(fs_info, chunk_start, 1);
+       if (IS_ERR(em))
                return -EIO;
-       }
 
-       if (em->start != chunk_start) {
-               btrfs_err(fs_info, "bad chunk start, em=%Lu, wanted=%Lu",
-                      em->start, chunk_start);
-               free_extent_map(em);
-               return -EIO;
-       }
        map = em->map_lookup;
-
        length = em->len;
        rmap_len = map->stripe_len;
 

diff --git a/fs/btrfs/volumes.h b/fs/btrfs/volumes.h
index ac0bf7d0df60e8f2c49aff3929c88253864b7e37..9ee6b706db310b4ba2806400829b6fe2fa88044d 100644 (file)
--- a/fs/btrfs/volumes.h
+++ b/fs/btrfs/volumes.h
@@ -475,7 +475,7 @@ void btrfs_destroy_dev_replace_tgtdev(struct btrfs_fs_info *fs_info,
 void btrfs_init_dev_replace_tgtdev_for_resume(struct btrfs_fs_info *fs_info,
                                              struct btrfs_device *tgtdev);
 void btrfs_scratch_superblocks(struct block_device *bdev, const char *device_path);
-int btrfs_is_parity_mirror(struct btrfs_mapping_tree *map_tree,
+int btrfs_is_parity_mirror(struct btrfs_fs_info *fs_info,
                           u64 logical, u64 len, int mirror_num);
 unsigned long btrfs_full_stripe_len(struct btrfs_fs_info *fs_info,
                                    struct btrfs_mapping_tree *map_tree,