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Diffstat (limited to 'fs/btrfs/ordered-data.c')
-rw-r--r--fs/btrfs/ordered-data.c70
1 files changed, 56 insertions, 14 deletions
diff --git a/fs/btrfs/ordered-data.c b/fs/btrfs/ordered-data.c
index 52170cf17..8c27292ea 100644
--- a/fs/btrfs/ordered-data.c
+++ b/fs/btrfs/ordered-data.c
@@ -345,6 +345,9 @@ int btrfs_dec_test_first_ordered_pending(struct inode *inode,
if (entry->bytes_left == 0) {
ret = test_and_set_bit(BTRFS_ORDERED_IO_DONE, &entry->flags);
+ /*
+ * Implicit memory barrier after test_and_set_bit
+ */
if (waitqueue_active(&entry->wait))
wake_up(&entry->wait);
} else {
@@ -409,6 +412,9 @@ have_entry:
if (entry->bytes_left == 0) {
ret = test_and_set_bit(BTRFS_ORDERED_IO_DONE, &entry->flags);
+ /*
+ * Implicit memory barrier after test_and_set_bit
+ */
if (waitqueue_active(&entry->wait))
wake_up(&entry->wait);
} else {
@@ -484,15 +490,16 @@ void btrfs_wait_logged_extents(struct btrfs_trans_handle *trans,
spin_lock_irq(&log->log_extents_lock[index]);
while (!list_empty(&log->logged_list[index])) {
+ struct inode *inode;
ordered = list_first_entry(&log->logged_list[index],
struct btrfs_ordered_extent,
log_list);
list_del_init(&ordered->log_list);
+ inode = ordered->inode;
spin_unlock_irq(&log->log_extents_lock[index]);
if (!test_bit(BTRFS_ORDERED_IO_DONE, &ordered->flags) &&
!test_bit(BTRFS_ORDERED_DIRECT, &ordered->flags)) {
- struct inode *inode = ordered->inode;
u64 start = ordered->file_offset;
u64 end = ordered->file_offset + ordered->len - 1;
@@ -503,20 +510,25 @@ void btrfs_wait_logged_extents(struct btrfs_trans_handle *trans,
&ordered->flags));
/*
- * If our ordered extent completed it means it updated the
- * fs/subvol and csum trees already, so no need to make the
- * current transaction's commit wait for it, as we end up
- * holding memory unnecessarily and delaying the inode's iput
- * until the transaction commit (we schedule an iput for the
- * inode when the ordered extent's refcount drops to 0), which
- * prevents it from being evictable until the transaction
- * commits.
+ * In order to keep us from losing our ordered extent
+ * information when committing the transaction we have to make
+ * sure that any logged extents are completed when we go to
+ * commit the transaction. To do this we simply increase the
+ * current transactions pending_ordered counter and decrement it
+ * when the ordered extent completes.
*/
- if (test_bit(BTRFS_ORDERED_COMPLETE, &ordered->flags))
- btrfs_put_ordered_extent(ordered);
- else
- list_add_tail(&ordered->trans_list, &trans->ordered);
-
+ if (!test_bit(BTRFS_ORDERED_COMPLETE, &ordered->flags)) {
+ struct btrfs_ordered_inode_tree *tree;
+
+ tree = &BTRFS_I(inode)->ordered_tree;
+ spin_lock_irq(&tree->lock);
+ if (!test_bit(BTRFS_ORDERED_COMPLETE, &ordered->flags)) {
+ set_bit(BTRFS_ORDERED_PENDING, &ordered->flags);
+ atomic_inc(&trans->transaction->pending_ordered);
+ }
+ spin_unlock_irq(&tree->lock);
+ }
+ btrfs_put_ordered_extent(ordered);
spin_lock_irq(&log->log_extents_lock[index]);
}
spin_unlock_irq(&log->log_extents_lock[index]);
@@ -578,6 +590,7 @@ void btrfs_remove_ordered_extent(struct inode *inode,
struct btrfs_ordered_inode_tree *tree;
struct btrfs_root *root = BTRFS_I(inode)->root;
struct rb_node *node;
+ bool dec_pending_ordered = false;
tree = &BTRFS_I(inode)->ordered_tree;
spin_lock_irq(&tree->lock);
@@ -587,8 +600,37 @@ void btrfs_remove_ordered_extent(struct inode *inode,
if (tree->last == node)
tree->last = NULL;
set_bit(BTRFS_ORDERED_COMPLETE, &entry->flags);
+ if (test_and_clear_bit(BTRFS_ORDERED_PENDING, &entry->flags))
+ dec_pending_ordered = true;
spin_unlock_irq(&tree->lock);
+ /*
+ * The current running transaction is waiting on us, we need to let it
+ * know that we're complete and wake it up.
+ */
+ if (dec_pending_ordered) {
+ struct btrfs_transaction *trans;
+
+ /*
+ * The checks for trans are just a formality, it should be set,
+ * but if it isn't we don't want to deref/assert under the spin
+ * lock, so be nice and check if trans is set, but ASSERT() so
+ * if it isn't set a developer will notice.
+ */
+ spin_lock(&root->fs_info->trans_lock);
+ trans = root->fs_info->running_transaction;
+ if (trans)
+ atomic_inc(&trans->use_count);
+ spin_unlock(&root->fs_info->trans_lock);
+
+ ASSERT(trans);
+ if (trans) {
+ if (atomic_dec_and_test(&trans->pending_ordered))
+ wake_up(&trans->pending_wait);
+ btrfs_put_transaction(trans);
+ }
+ }
+
spin_lock(&root->ordered_extent_lock);
list_del_init(&entry->root_extent_list);
root->nr_ordered_extents--;