Btrfs: devid filter

Relocate chunks which have at least one stripe located on a device with
devid X.

Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

1 files changed, 23 insertions, 0 deletions

diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index b858242374db..9ff5cd09a256 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -2150,6 +2150,23 @@ static int chunk_usage_filter(struct btrfs_fs_info *fs_info, u64 chunk_offset,
         return ret;
 }
 
+static int chunk_devid_filter(struct extent_buffer *leaf,
+                              struct btrfs_chunk *chunk,
+                              struct btrfs_balance_args *bargs)
+{
+        struct btrfs_stripe *stripe;
+        int num_stripes = btrfs_chunk_num_stripes(leaf, chunk);
+        int i;
+
+        for (i = 0; i < num_stripes; i++) {
+                stripe = btrfs_stripe_nr(chunk, i);
+                if (btrfs_stripe_devid(leaf, stripe) == bargs->devid)
+                        return 0;
+        }
+
+        return 1;
+}
+
 static int should_balance_chunk(struct btrfs_root *root,
                                 struct extent_buffer *leaf,
                                 struct btrfs_chunk *chunk, u64 chunk_offset)
@@ -2183,6 +2200,12 @@ static int should_balance_chunk(struct btrfs_root *root,
                 return 0;
         }
 
+        /* devid filter */
+        if ((bargs->flags & BTRFS_BALANCE_ARGS_DEVID) &&
+            chunk_devid_filter(leaf, chunk, bargs)) {
+                return 0;
+        }
+
         return 1;
 }