1 files changed, 61 insertions, 16 deletions

diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index 66bac226944e..f5be06a2462f 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -1782,6 +1782,9 @@ static int btrfs_discard_extent(struct btrfs_root *root, u64 bytenr,
 
 
                 for (i = 0; i < multi->num_stripes; i++, stripe++) {
+                        if (!stripe->dev->can_discard)
+                                continue;
+
                         ret = btrfs_issue_discard(stripe->dev->bdev,
                                                   stripe->physical,
                                                   stripe->length);
@@ -1789,11 +1792,16 @@ static int btrfs_discard_extent(struct btrfs_root *root, u64 bytenr,
                                 discarded_bytes += stripe->length;
                         else if (ret != -EOPNOTSUPP)
                                 break;
+
+                        /*
+                         * Just in case we get back EOPNOTSUPP for some reason,
+                         * just ignore the return value so we don't screw up
+                         * people calling discard_extent.
+                         */
+                        ret = 0;
                 }
                 kfree(multi);
         }
-        if (discarded_bytes && ret == -EOPNOTSUPP)
-                ret = 0;
 
         if (actual_bytes)
                 *actual_bytes = discarded_bytes;
@@ -6269,8 +6277,8 @@ static noinline int walk_up_tree(struct btrfs_trans_handle *trans,
  * also make sure backrefs for the shared block and all lower level
  * blocks are properly updated.
  */
-int btrfs_drop_snapshot(struct btrfs_root *root,
-                        struct btrfs_block_rsv *block_rsv, int update_ref)
+void btrfs_drop_snapshot(struct btrfs_root *root,
+                         struct btrfs_block_rsv *block_rsv, int update_ref)
 {
         struct btrfs_path *path;
         struct btrfs_trans_handle *trans;
@@ -6283,13 +6291,16 @@ int btrfs_drop_snapshot(struct btrfs_root *root,
         int level;
 
         path = btrfs_alloc_path();
-        if (!path)
-                return -ENOMEM;
+        if (!path) {
+                err = -ENOMEM;
+                goto out;
+        }
 
         wc = kzalloc(sizeof(*wc), GFP_NOFS);
         if (!wc) {
                 btrfs_free_path(path);
-                return -ENOMEM;
+                err = -ENOMEM;
+                goto out;
         }
 
         trans = btrfs_start_transaction(tree_root, 0);
@@ -6318,7 +6329,7 @@ int btrfs_drop_snapshot(struct btrfs_root *root,
                 path->lowest_level = 0;
                 if (ret < 0) {
                         err = ret;
-                        goto out;
+                        goto out_free;
                 }
                 WARN_ON(ret > 0);
 
@@ -6425,11 +6436,14 @@ int btrfs_drop_snapshot(struct btrfs_root *root,
                 free_extent_buffer(root->commit_root);
                 kfree(root);
         }
-out:
+out_free:
         btrfs_end_transaction_throttle(trans, tree_root);
         kfree(wc);
         btrfs_free_path(path);
-        return err;
+out:
+        if (err)
+                btrfs_std_error(root->fs_info, err);
+        return;
 }
 
 /*
@@ -6720,6 +6734,10 @@ int btrfs_can_relocate(struct btrfs_root *root, u64 bytenr)
         struct btrfs_space_info *space_info;
         struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
         struct btrfs_device *device;
+        u64 min_free;
+        u64 dev_min = 1;
+        u64 dev_nr = 0;
+        int index;
         int full = 0;
         int ret = 0;
 
@@ -6729,8 +6747,10 @@ int btrfs_can_relocate(struct btrfs_root *root, u64 bytenr)
         if (!block_group)
                 return -1;
 
+        min_free = btrfs_block_group_used(&block_group->item);
+
         /* no bytes used, we're good */
-        if (!btrfs_block_group_used(&block_group->item))
+        if (!min_free)
                 goto out;
 
         space_info = block_group->space_info;
@@ -6746,10 +6766,9 @@ int btrfs_can_relocate(struct btrfs_root *root, u64 bytenr)
          * all of the extents from this block group.  If we can, we're good
          */
         if ((space_info->total_bytes != block_group->key.offset) &&
-           (space_info->bytes_used + space_info->bytes_reserved +
-            space_info->bytes_pinned + space_info->bytes_readonly +
-            btrfs_block_group_used(&block_group->item) <
-            space_info->total_bytes)) {
+            (space_info->bytes_used + space_info->bytes_reserved +
+             space_info->bytes_pinned + space_info->bytes_readonly +
+             min_free < space_info->total_bytes)) {
                 spin_unlock(&space_info->lock);
                 goto out;
         }
@@ -6766,9 +6785,31 @@ int btrfs_can_relocate(struct btrfs_root *root, u64 bytenr)
         if (full)
                 goto out;
 
+        /*
+         * index:
+         *      0: raid10
+         *      1: raid1
+         *      2: dup
+         *      3: raid0
+         *      4: single
+         */
+        index = get_block_group_index(block_group);
+        if (index == 0) {
+                dev_min = 4;
+                /* Divide by 2 */
+                min_free >>= 1;
+        } else if (index == 1) {
+                dev_min = 2;
+        } else if (index == 2) {
+                /* Multiply by 2 */
+                min_free <<= 1;
+        } else if (index == 3) {
+                dev_min = fs_devices->rw_devices;
+                do_div(min_free, dev_min);
+        }
+
         mutex_lock(&root->fs_info->chunk_mutex);
         list_for_each_entry(device, &fs_devices->alloc_list, dev_alloc_list) {
-                u64 min_free = btrfs_block_group_used(&block_group->item);
                 u64 dev_offset;
 
                 /*
@@ -6779,7 +6820,11 @@ int btrfs_can_relocate(struct btrfs_root *root, u64 bytenr)
                         ret = find_free_dev_extent(NULL, device, min_free,
                                                    &dev_offset, NULL);
                         if (!ret)
+                                dev_nr++;
+
+                        if (dev_nr >= dev_min)
                                 break;
+
                         ret = -1;
                 }
         }