1 files changed, 59 insertions, 16 deletions

diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index bcd59c7dfb57..227e5815d838 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -429,6 +429,7 @@ err:
 
 static int cache_block_group(struct btrfs_block_group_cache *cache,
                              struct btrfs_trans_handle *trans,
+                             struct btrfs_root *root,
                              int load_cache_only)
 {
         struct btrfs_fs_info *fs_info = cache->fs_info;
@@ -442,9 +443,12 @@ static int cache_block_group(struct btrfs_block_group_cache *cache,
 
         /*
          * We can't do the read from on-disk cache during a commit since we need
-         * to have the normal tree locking.
+         * to have the normal tree locking.  Also if we are currently trying to
+         * 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->transaction->in_commit &&
+            (root && root != root->fs_info->tree_root)) {
                 spin_lock(&cache->lock);
                 if (cache->cached != BTRFS_CACHE_NO) {
                         spin_unlock(&cache->lock);
@@ -2741,6 +2745,7 @@ static int cache_save_setup(struct btrfs_block_group_cache *block_group,
         struct btrfs_root *root = block_group->fs_info->tree_root;
         struct inode *inode = NULL;
         u64 alloc_hint = 0;
+        int dcs = BTRFS_DC_ERROR;
         int num_pages = 0;
         int retries = 0;
         int ret = 0;
@@ -2795,6 +2800,8 @@ again:
 
         spin_lock(&block_group->lock);
         if (block_group->cached != BTRFS_CACHE_FINISHED) {
+                /* We're not cached, don't bother trying to write stuff out */
+                dcs = BTRFS_DC_WRITTEN;
                 spin_unlock(&block_group->lock);
                 goto out_put;
         }
@@ -2821,6 +2828,8 @@ again:
         ret = btrfs_prealloc_file_range_trans(inode, trans, 0, 0, num_pages,
                                               num_pages, num_pages,
                                               &alloc_hint);
+        if (!ret)
+                dcs = BTRFS_DC_SETUP;
         btrfs_free_reserved_data_space(inode, num_pages);
 out_put:
         iput(inode);
@@ -2828,10 +2837,7 @@ out_free:
         btrfs_release_path(root, path);
 out:
         spin_lock(&block_group->lock);
-        if (ret)
-                block_group->disk_cache_state = BTRFS_DC_ERROR;
-        else
-                block_group->disk_cache_state = BTRFS_DC_SETUP;
+        block_group->disk_cache_state = dcs;
         spin_unlock(&block_group->lock);
 
         return ret;
@@ -3037,7 +3043,13 @@ static void set_avail_alloc_bits(struct btrfs_fs_info *fs_info, u64 flags)
 
 u64 btrfs_reduce_alloc_profile(struct btrfs_root *root, u64 flags)
 {
-        u64 num_devices = root->fs_info->fs_devices->rw_devices;
+        /*
+         * we add in the count of missing devices because we want
+         * to make sure that any RAID levels on a degraded FS
+         * continue to be honored.
+         */
+        u64 num_devices = root->fs_info->fs_devices->rw_devices +
+                root->fs_info->fs_devices->missing_devices;
 
         if (num_devices == 1)
                 flags &= ~(BTRFS_BLOCK_GROUP_RAID1 | BTRFS_BLOCK_GROUP_RAID0);
@@ -4080,7 +4092,7 @@ static int update_block_group(struct btrfs_trans_handle *trans,
                  * space back to the block group, otherwise we will leak space.
                  */
                 if (!alloc && cache->cached == BTRFS_CACHE_NO)
-                        cache_block_group(cache, trans, 1);
+                        cache_block_group(cache, trans, NULL, 1);
 
                 byte_in_group = bytenr - cache->key.objectid;
                 WARN_ON(byte_in_group > cache->key.offset);
@@ -4930,11 +4942,31 @@ search:
                 btrfs_get_block_group(block_group);
                 search_start = block_group->key.objectid;
 
+                /*
+                 * this can happen if we end up cycling through all the
+                 * raid types, but we want to make sure we only allocate
+                 * for the proper type.
+                 */
+                if (!block_group_bits(block_group, data)) {
+                    u64 extra = BTRFS_BLOCK_GROUP_DUP |
+                                BTRFS_BLOCK_GROUP_RAID1 |
+                                BTRFS_BLOCK_GROUP_RAID10;
+
+                        /*
+                         * if they asked for extra copies and this block group
+                         * doesn't provide them, bail.  This does allow us to
+                         * fill raid0 from raid1.
+                         */
+                        if ((data & extra) && !(block_group->flags & extra))
+                                goto loop;
+                }
+
 have_block_group:
                 if (unlikely(block_group->cached == BTRFS_CACHE_NO)) {
                         u64 free_percent;
 
-                        ret = cache_block_group(block_group, trans, 1);
+                        ret = cache_block_group(block_group, trans,
+                                                orig_root, 1);
                         if (block_group->cached == BTRFS_CACHE_FINISHED)
                                 goto have_block_group;
 
@@ -4958,7 +4990,8 @@ have_block_group:
                         if (loop > LOOP_CACHING_NOWAIT ||
                             (loop > LOOP_FIND_IDEAL &&
                              atomic_read(&space_info->caching_threads) < 2)) {
-                                ret = cache_block_group(block_group, trans, 0);
+                                ret = cache_block_group(block_group, trans,
+                                                        orig_root, 0);
                                 BUG_ON(ret);
                         }
                         found_uncached_bg = true;
@@ -5515,7 +5548,7 @@ int btrfs_alloc_logged_file_extent(struct btrfs_trans_handle *trans,
         u64 num_bytes = ins->offset;
 
         block_group = btrfs_lookup_block_group(root->fs_info, ins->objectid);
-        cache_block_group(block_group, trans, 0);
+        cache_block_group(block_group, trans, NULL, 0);
         caching_ctl = get_caching_control(block_group);
 
         if (!caching_ctl) {
@@ -6300,9 +6333,13 @@ int btrfs_drop_snapshot(struct btrfs_root *root,
                                            NULL, NULL);
                 BUG_ON(ret < 0);
                 if (ret > 0) {
-                        ret = btrfs_del_orphan_item(trans, tree_root,
-                                                    root->root_key.objectid);
-                        BUG_ON(ret);
+                        /* if we fail to delete the orphan item this time
+                         * around, it'll get picked up the next time.
+                         *
+                         * The most common failure here is just -ENOENT.
+                         */
+                        btrfs_del_orphan_item(trans, tree_root,
+                                              root->root_key.objectid);
                 }
         }
 
@@ -7878,7 +7915,14 @@ static u64 update_block_group_flags(struct btrfs_root *root, u64 flags)
         u64 stripped = BTRFS_BLOCK_GROUP_RAID0 |
                 BTRFS_BLOCK_GROUP_RAID1 | BTRFS_BLOCK_GROUP_RAID10;
 
-        num_devices = root->fs_info->fs_devices->rw_devices;
+        /*
+         * we add in the count of missing devices because we want
+         * to make sure that any RAID levels on a degraded FS
+         * continue to be honored.
+         */
+        num_devices = root->fs_info->fs_devices->rw_devices +
+                root->fs_info->fs_devices->missing_devices;
+
         if (num_devices == 1) {
                 stripped |= BTRFS_BLOCK_GROUP_DUP;
                 stripped = flags & ~stripped;
@@ -8247,7 +8291,6 @@ int btrfs_read_block_groups(struct btrfs_root *root)
                         break;
                 if (ret != 0)
                         goto error;
-
                 leaf = path->nodes[0];
                 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
                 cache = kzalloc(sizeof(*cache), GFP_NOFS);