Btrfs: write out free space cache
This is a simple bit, just dump the free space cache out to our preallocated
inode when we're writing out dirty block groups. There are a bunch of changes
in inode.c in order to account for special cases. Mostly when we're doing the
writeout we're holding trans_mutex, so we need to use the nolock transacation
functions. Also we can't do asynchronous completions since the async thread
could be blocked on already completed IO waiting for the transaction lock. This
has been tested with xfstests and btrfs filesystem balance, as well as my ENOSPC
tests. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 1af1ea8..f2fb974 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -764,6 +764,7 @@
struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
int ret = 0;
+ BUG_ON(root == root->fs_info->tree_root);
trans = btrfs_join_transaction(root, 1);
BUG_ON(!trans);
btrfs_set_trans_block_group(trans, inode);
@@ -1035,10 +1036,16 @@
int type;
int nocow;
int check_prev = 1;
+ bool nolock = false;
path = btrfs_alloc_path();
BUG_ON(!path);
- trans = btrfs_join_transaction(root, 1);
+ if (root == root->fs_info->tree_root) {
+ nolock = true;
+ trans = btrfs_join_transaction_nolock(root, 1);
+ } else {
+ trans = btrfs_join_transaction(root, 1);
+ }
BUG_ON(!trans);
cow_start = (u64)-1;
@@ -1211,8 +1218,13 @@
BUG_ON(ret);
}
- ret = btrfs_end_transaction(trans, root);
- BUG_ON(ret);
+ if (nolock) {
+ ret = btrfs_end_transaction_nolock(trans, root);
+ BUG_ON(ret);
+ } else {
+ ret = btrfs_end_transaction(trans, root);
+ BUG_ON(ret);
+ }
btrfs_free_path(path);
return 0;
}
@@ -1289,6 +1301,8 @@
if (!(state->state & EXTENT_DELALLOC) && (*bits & EXTENT_DELALLOC)) {
struct btrfs_root *root = BTRFS_I(inode)->root;
u64 len = state->end + 1 - state->start;
+ int do_list = (root->root_key.objectid !=
+ BTRFS_ROOT_TREE_OBJECTID);
if (*bits & EXTENT_FIRST_DELALLOC)
*bits &= ~EXTENT_FIRST_DELALLOC;
@@ -1298,7 +1312,7 @@
spin_lock(&root->fs_info->delalloc_lock);
BTRFS_I(inode)->delalloc_bytes += len;
root->fs_info->delalloc_bytes += len;
- if (list_empty(&BTRFS_I(inode)->delalloc_inodes)) {
+ if (do_list && list_empty(&BTRFS_I(inode)->delalloc_inodes)) {
list_add_tail(&BTRFS_I(inode)->delalloc_inodes,
&root->fs_info->delalloc_inodes);
}
@@ -1321,6 +1335,8 @@
if ((state->state & EXTENT_DELALLOC) && (*bits & EXTENT_DELALLOC)) {
struct btrfs_root *root = BTRFS_I(inode)->root;
u64 len = state->end + 1 - state->start;
+ int do_list = (root->root_key.objectid !=
+ BTRFS_ROOT_TREE_OBJECTID);
if (*bits & EXTENT_FIRST_DELALLOC)
*bits &= ~EXTENT_FIRST_DELALLOC;
@@ -1330,14 +1346,15 @@
if (*bits & EXTENT_DO_ACCOUNTING)
btrfs_delalloc_release_metadata(inode, len);
- if (root->root_key.objectid != BTRFS_DATA_RELOC_TREE_OBJECTID)
+ if (root->root_key.objectid != BTRFS_DATA_RELOC_TREE_OBJECTID
+ && do_list)
btrfs_free_reserved_data_space(inode, len);
spin_lock(&root->fs_info->delalloc_lock);
root->fs_info->delalloc_bytes -= len;
BTRFS_I(inode)->delalloc_bytes -= len;
- if (BTRFS_I(inode)->delalloc_bytes == 0 &&
+ if (do_list && BTRFS_I(inode)->delalloc_bytes == 0 &&
!list_empty(&BTRFS_I(inode)->delalloc_inodes)) {
list_del_init(&BTRFS_I(inode)->delalloc_inodes);
}
@@ -1426,7 +1443,10 @@
skip_sum = BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM;
- ret = btrfs_bio_wq_end_io(root->fs_info, bio, 0);
+ if (root == root->fs_info->tree_root)
+ ret = btrfs_bio_wq_end_io(root->fs_info, bio, 2);
+ else
+ ret = btrfs_bio_wq_end_io(root->fs_info, bio, 0);
BUG_ON(ret);
if (!(rw & REQ_WRITE)) {
@@ -1662,6 +1682,7 @@
struct extent_state *cached_state = NULL;
int compressed = 0;
int ret;
+ bool nolock = false;
ret = btrfs_dec_test_ordered_pending(inode, &ordered_extent, start,
end - start + 1);
@@ -1669,11 +1690,17 @@
return 0;
BUG_ON(!ordered_extent);
+ nolock = (root == root->fs_info->tree_root);
+
if (test_bit(BTRFS_ORDERED_NOCOW, &ordered_extent->flags)) {
BUG_ON(!list_empty(&ordered_extent->list));
ret = btrfs_ordered_update_i_size(inode, 0, ordered_extent);
if (!ret) {
- trans = btrfs_join_transaction(root, 1);
+ if (nolock)
+ trans = btrfs_join_transaction_nolock(root, 1);
+ else
+ trans = btrfs_join_transaction(root, 1);
+ BUG_ON(!trans);
btrfs_set_trans_block_group(trans, inode);
trans->block_rsv = &root->fs_info->delalloc_block_rsv;
ret = btrfs_update_inode(trans, root, inode);
@@ -1686,7 +1713,10 @@
ordered_extent->file_offset + ordered_extent->len - 1,
0, &cached_state, GFP_NOFS);
- 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);
trans->block_rsv = &root->fs_info->delalloc_block_rsv;
@@ -1725,9 +1755,15 @@
ret = btrfs_update_inode(trans, root, inode);
BUG_ON(ret);
out:
- btrfs_delalloc_release_metadata(inode, ordered_extent->len);
- if (trans)
- btrfs_end_transaction(trans, root);
+ if (nolock) {
+ if (trans)
+ btrfs_end_transaction_nolock(trans, root);
+ } else {
+ btrfs_delalloc_release_metadata(inode, ordered_extent->len);
+ if (trans)
+ btrfs_end_transaction(trans, root);
+ }
+
/* once for us */
btrfs_put_ordered_extent(ordered_extent);
/* once for the tree */