diff options
author | Josef Bacik <josef@redhat.com> | 2010-06-21 18:48:16 (GMT) |
---|---|---|
committer | Josef Bacik <josef@redhat.com> | 2010-10-28 19:59:09 (GMT) |
commit | 0af3d00bad38d3bb9912a60928ad0669f17bdb76 (patch) | |
tree | abbf4c773138a33dcde483ac60f016c4b5e55dcc /fs/btrfs/inode.c | |
parent | f6f94e2ab1b33f0082ac22d71f66385a60d8157f (diff) | |
download | linux-fsl-qoriq-0af3d00bad38d3bb9912a60928ad0669f17bdb76.tar.xz |
Btrfs: create special free space cache inode
In order to save free space cache, we need an inode to hold the data, and we
need a special item to point at the right inode for the right block group. So
first, create a special item that will point to the right inode, and the number
of extent entries we will have and the number of bitmaps we will have. We
truncate and pre-allocate space everytime to make sure it's uptodate.
This feature will be turned on as soon as you mount with -o space_cache, however
it is safe to boot into old kernels, they will just generate the cache the old
fashion way. When you boot back into a newer kernel we will notice that we
modified and not the cache and automatically discard the cache.
Signed-off-by: Josef Bacik <josef@redhat.com>
Diffstat (limited to 'fs/btrfs/inode.c')
-rw-r--r-- | fs/btrfs/inode.c | 95 |
1 files changed, 78 insertions, 17 deletions
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index c038644..1af1ea8 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -1700,6 +1700,7 @@ static int btrfs_finish_ordered_io(struct inode *inode, u64 start, u64 end) ordered_extent->len); BUG_ON(ret); } else { + BUG_ON(root == root->fs_info->tree_root); ret = insert_reserved_file_extent(trans, inode, ordered_extent->file_offset, ordered_extent->start, @@ -3196,7 +3197,7 @@ int btrfs_truncate_inode_items(struct btrfs_trans_handle *trans, BUG_ON(new_size > 0 && min_type != BTRFS_EXTENT_DATA_KEY); - if (root->ref_cows) + if (root->ref_cows || root == root->fs_info->tree_root) btrfs_drop_extent_cache(inode, new_size & (~mask), (u64)-1, 0); path = btrfs_alloc_path(); @@ -3344,7 +3345,8 @@ delete: } else { break; } - if (found_extent && root->ref_cows) { + if (found_extent && (root->ref_cows || + root == root->fs_info->tree_root)) { btrfs_set_path_blocking(path); ret = btrfs_free_extent(trans, root, extent_start, extent_num_bytes, 0, @@ -3675,7 +3677,8 @@ void btrfs_evict_inode(struct inode *inode) int ret; truncate_inode_pages(&inode->i_data, 0); - if (inode->i_nlink && btrfs_root_refs(&root->root_item) != 0) + if (inode->i_nlink && (btrfs_root_refs(&root->root_item) != 0 || + root == root->fs_info->tree_root)) goto no_delete; if (is_bad_inode(inode)) { @@ -3888,7 +3891,14 @@ static void inode_tree_del(struct inode *inode) } spin_unlock(&root->inode_lock); - if (empty && btrfs_root_refs(&root->root_item) == 0) { + /* + * Free space cache has inodes in the tree root, but the tree root has a + * root_refs of 0, so this could end up dropping the tree root as a + * snapshot, so we need the extra !root->fs_info->tree_root check to + * make sure we don't drop it. + */ + if (empty && btrfs_root_refs(&root->root_item) == 0 && + root != root->fs_info->tree_root) { synchronize_srcu(&root->fs_info->subvol_srcu); spin_lock(&root->inode_lock); empty = RB_EMPTY_ROOT(&root->inode_tree); @@ -4282,14 +4292,24 @@ int btrfs_write_inode(struct inode *inode, struct writeback_control *wbc) struct btrfs_root *root = BTRFS_I(inode)->root; struct btrfs_trans_handle *trans; int ret = 0; + bool nolock = false; if (BTRFS_I(inode)->dummy_inode) return 0; + smp_mb(); + nolock = (root->fs_info->closing && root == root->fs_info->tree_root); + if (wbc->sync_mode == WB_SYNC_ALL) { - trans = btrfs_join_transaction(root, 1); + if (nolock) + trans = btrfs_join_transaction_nolock(root, 1); + else + trans = btrfs_join_transaction(root, 1); btrfs_set_trans_block_group(trans, inode); - ret = btrfs_commit_transaction(trans, root); + if (nolock) + ret = btrfs_end_transaction_nolock(trans, root); + else + ret = btrfs_commit_transaction(trans, root); } return ret; } @@ -6308,6 +6328,21 @@ void btrfs_destroy_inode(struct inode *inode) spin_unlock(&root->fs_info->ordered_extent_lock); } + if (root == root->fs_info->tree_root) { + struct btrfs_block_group_cache *block_group; + + block_group = btrfs_lookup_block_group(root->fs_info, + BTRFS_I(inode)->block_group); + if (block_group && block_group->inode == inode) { + spin_lock(&block_group->lock); + block_group->inode = NULL; + spin_unlock(&block_group->lock); + btrfs_put_block_group(block_group); + } else if (block_group) { + btrfs_put_block_group(block_group); + } + } + spin_lock(&root->orphan_lock); if (!list_empty(&BTRFS_I(inode)->i_orphan)) { printk(KERN_INFO "BTRFS: inode %lu still on the orphan list\n", @@ -6340,7 +6375,8 @@ int btrfs_drop_inode(struct inode *inode) { struct btrfs_root *root = BTRFS_I(inode)->root; - if (btrfs_root_refs(&root->root_item) == 0) + if (btrfs_root_refs(&root->root_item) == 0 && + root != root->fs_info->tree_root) return 1; else return generic_drop_inode(inode); @@ -6757,27 +6793,33 @@ out_unlock: return err; } -int btrfs_prealloc_file_range(struct inode *inode, int mode, - u64 start, u64 num_bytes, u64 min_size, - loff_t actual_len, u64 *alloc_hint) +static int __btrfs_prealloc_file_range(struct inode *inode, int mode, + u64 start, u64 num_bytes, u64 min_size, + loff_t actual_len, u64 *alloc_hint, + struct btrfs_trans_handle *trans) { - struct btrfs_trans_handle *trans; struct btrfs_root *root = BTRFS_I(inode)->root; struct btrfs_key ins; u64 cur_offset = start; int ret = 0; + bool own_trans = true; + if (trans) + own_trans = false; while (num_bytes > 0) { - trans = btrfs_start_transaction(root, 3); - if (IS_ERR(trans)) { - ret = PTR_ERR(trans); - break; + if (own_trans) { + trans = btrfs_start_transaction(root, 3); + if (IS_ERR(trans)) { + ret = PTR_ERR(trans); + break; + } } ret = btrfs_reserve_extent(trans, root, num_bytes, min_size, 0, *alloc_hint, (u64)-1, &ins, 1); if (ret) { - btrfs_end_transaction(trans, root); + if (own_trans) + btrfs_end_transaction(trans, root); break; } @@ -6810,11 +6852,30 @@ int btrfs_prealloc_file_range(struct inode *inode, int mode, ret = btrfs_update_inode(trans, root, inode); BUG_ON(ret); - btrfs_end_transaction(trans, root); + if (own_trans) + btrfs_end_transaction(trans, root); } return ret; } +int btrfs_prealloc_file_range(struct inode *inode, int mode, + u64 start, u64 num_bytes, u64 min_size, + loff_t actual_len, u64 *alloc_hint) +{ + return __btrfs_prealloc_file_range(inode, mode, start, num_bytes, + min_size, actual_len, alloc_hint, + NULL); +} + +int btrfs_prealloc_file_range_trans(struct inode *inode, + struct btrfs_trans_handle *trans, int mode, + u64 start, u64 num_bytes, u64 min_size, + loff_t actual_len, u64 *alloc_hint) +{ + return __btrfs_prealloc_file_range(inode, mode, start, num_bytes, + min_size, actual_len, alloc_hint, trans); +} + static long btrfs_fallocate(struct inode *inode, int mode, loff_t offset, loff_t len) { |