Btrfs: add btrfs_trim_fs() to handle FITRIM

[deliverable/linux.git] / fs / btrfs / extent-tree.c

diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index e990d2d1ba4ade0fc40660d4d4114a792564988a..1efeda3b2f6f95492c036ec7fd53c021138fb15f 100644 (file)
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -440,7 +440,7 @@ static int cache_block_group(struct btrfs_block_group_cache *cache,
         * allocate blocks for the tree root we can't do the fast caching since
         * we likely hold important locks.
         */
-       if (!trans->transaction->in_commit &&
+       if (trans && (!trans->transaction->in_commit) &&
            (root && root != root->fs_info->tree_root)) {
                spin_lock(&cache->lock);
                if (cache->cached != BTRFS_CACHE_NO) {
@@ -8778,3 +8778,51 @@ int btrfs_error_discard_extent(struct btrfs_root *root, u64 bytenr,
 {
        return btrfs_discard_extent(root, bytenr, num_bytes, actual_bytes);
 }
+
+int btrfs_trim_fs(struct btrfs_root *root, struct fstrim_range *range)
+{
+       struct btrfs_fs_info *fs_info = root->fs_info;
+       struct btrfs_block_group_cache *cache = NULL;
+       u64 group_trimmed;
+       u64 start;
+       u64 end;
+       u64 trimmed = 0;
+       int ret = 0;
+
+       cache = btrfs_lookup_block_group(fs_info, range->start);
+
+       while (cache) {
+               if (cache->key.objectid >= (range->start + range->len)) {
+                       btrfs_put_block_group(cache);
+                       break;
+               }
+
+               start = max(range->start, cache->key.objectid);
+               end = min(range->start + range->len,
+                               cache->key.objectid + cache->key.offset);
+
+               if (end - start >= range->minlen) {
+                       if (!block_group_cache_done(cache)) {
+                               ret = cache_block_group(cache, NULL, root, 0);
+                               if (!ret)
+                                       wait_block_group_cache_done(cache);
+                       }
+                       ret = btrfs_trim_block_group(cache,
+                                                    &group_trimmed,
+                                                    start,
+                                                    end,
+                                                    range->minlen);
+
+                       trimmed += group_trimmed;
+                       if (ret) {
+                               btrfs_put_block_group(cache);
+                               break;
+                       }
+               }
+
+               cache = next_block_group(fs_info->tree_root, cache);
+       }
+
+       range->len = trimmed;
+       return ret;
+}