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Diffstat (limited to 'fs/btrfs/transaction.c')
-rw-r--r--fs/btrfs/transaction.c80
1 files changed, 55 insertions, 25 deletions
diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c
index f50e931fc21..c571734d5e5 100644
--- a/fs/btrfs/transaction.c
+++ b/fs/btrfs/transaction.c
@@ -32,10 +32,8 @@
static noinline void put_transaction(struct btrfs_transaction *transaction)
{
- WARN_ON(transaction->use_count == 0);
- transaction->use_count--;
- if (transaction->use_count == 0) {
- list_del_init(&transaction->list);
+ WARN_ON(atomic_read(&transaction->use_count) == 0);
+ if (atomic_dec_and_test(&transaction->use_count)) {
memset(transaction, 0, sizeof(*transaction));
kmem_cache_free(btrfs_transaction_cachep, transaction);
}
@@ -57,16 +55,17 @@ static noinline int join_transaction(struct btrfs_root *root)
if (!cur_trans) {
cur_trans = kmem_cache_alloc(btrfs_transaction_cachep,
GFP_NOFS);
- BUG_ON(!cur_trans);
+ if (!cur_trans)
+ return -ENOMEM;
root->fs_info->generation++;
- cur_trans->num_writers = 1;
+ atomic_set(&cur_trans->num_writers, 1);
cur_trans->num_joined = 0;
cur_trans->transid = root->fs_info->generation;
init_waitqueue_head(&cur_trans->writer_wait);
init_waitqueue_head(&cur_trans->commit_wait);
cur_trans->in_commit = 0;
cur_trans->blocked = 0;
- cur_trans->use_count = 1;
+ atomic_set(&cur_trans->use_count, 1);
cur_trans->commit_done = 0;
cur_trans->start_time = get_seconds();
@@ -87,7 +86,7 @@ static noinline int join_transaction(struct btrfs_root *root)
root->fs_info->running_transaction = cur_trans;
spin_unlock(&root->fs_info->new_trans_lock);
} else {
- cur_trans->num_writers++;
+ atomic_inc(&cur_trans->num_writers);
cur_trans->num_joined++;
}
@@ -144,7 +143,7 @@ static void wait_current_trans(struct btrfs_root *root)
cur_trans = root->fs_info->running_transaction;
if (cur_trans && cur_trans->blocked) {
DEFINE_WAIT(wait);
- cur_trans->use_count++;
+ atomic_inc(&cur_trans->use_count);
while (1) {
prepare_to_wait(&root->fs_info->transaction_wait, &wait,
TASK_UNINTERRUPTIBLE);
@@ -180,7 +179,11 @@ static struct btrfs_trans_handle *start_transaction(struct btrfs_root *root,
{
struct btrfs_trans_handle *h;
struct btrfs_transaction *cur_trans;
+ int retries = 0;
int ret;
+
+ if (root->fs_info->fs_state & BTRFS_SUPER_FLAG_ERROR)
+ return ERR_PTR(-EROFS);
again:
h = kmem_cache_alloc(btrfs_trans_handle_cachep, GFP_NOFS);
if (!h)
@@ -192,10 +195,15 @@ again:
wait_current_trans(root);
ret = join_transaction(root);
- BUG_ON(ret);
+ if (ret < 0) {
+ kmem_cache_free(btrfs_trans_handle_cachep, h);
+ if (type != TRANS_JOIN_NOLOCK)
+ mutex_unlock(&root->fs_info->trans_mutex);
+ return ERR_PTR(ret);
+ }
cur_trans = root->fs_info->running_transaction;
- cur_trans->use_count++;
+ atomic_inc(&cur_trans->use_count);
if (type != TRANS_JOIN_NOLOCK)
mutex_unlock(&root->fs_info->trans_mutex);
@@ -215,10 +223,18 @@ again:
if (num_items > 0) {
ret = btrfs_trans_reserve_metadata(h, root, num_items);
- if (ret == -EAGAIN) {
+ if (ret == -EAGAIN && !retries) {
+ retries++;
btrfs_commit_transaction(h, root);
goto again;
+ } else if (ret == -EAGAIN) {
+ /*
+ * We have already retried and got EAGAIN, so really we
+ * don't have space, so set ret to -ENOSPC.
+ */
+ ret = -ENOSPC;
}
+
if (ret < 0) {
btrfs_end_transaction(h, root);
return ERR_PTR(ret);
@@ -318,7 +334,7 @@ int btrfs_wait_for_commit(struct btrfs_root *root, u64 transid)
goto out_unlock; /* nothing committing|committed */
}
- cur_trans->use_count++;
+ atomic_inc(&cur_trans->use_count);
mutex_unlock(&root->fs_info->trans_mutex);
wait_for_commit(root, cur_trans);
@@ -448,18 +464,14 @@ static int __btrfs_end_transaction(struct btrfs_trans_handle *trans,
wake_up_process(info->transaction_kthread);
}
- if (lock)
- mutex_lock(&info->trans_mutex);
WARN_ON(cur_trans != info->running_transaction);
- WARN_ON(cur_trans->num_writers < 1);
- cur_trans->num_writers--;
+ WARN_ON(atomic_read(&cur_trans->num_writers) < 1);
+ atomic_dec(&cur_trans->num_writers);
smp_mb();
if (waitqueue_active(&cur_trans->writer_wait))
wake_up(&cur_trans->writer_wait);
put_transaction(cur_trans);
- if (lock)
- mutex_unlock(&info->trans_mutex);
if (current->journal_info == trans)
current->journal_info = NULL;
@@ -910,6 +922,7 @@ static noinline int create_pending_snapshot(struct btrfs_trans_handle *trans,
u64 to_reserve = 0;
u64 index = 0;
u64 objectid;
+ u64 root_flags;
new_root_item = kmalloc(sizeof(*new_root_item), GFP_NOFS);
if (!new_root_item) {
@@ -966,6 +979,14 @@ static noinline int create_pending_snapshot(struct btrfs_trans_handle *trans,
record_root_in_trans(trans, root);
btrfs_set_root_last_snapshot(&root->root_item, trans->transid);
memcpy(new_root_item, &root->root_item, sizeof(*new_root_item));
+ btrfs_check_and_init_root_item(new_root_item);
+
+ root_flags = btrfs_root_flags(new_root_item);
+ if (pending->readonly)
+ root_flags |= BTRFS_ROOT_SUBVOL_RDONLY;
+ else
+ root_flags &= ~BTRFS_ROOT_SUBVOL_RDONLY;
+ btrfs_set_root_flags(new_root_item, root_flags);
old = btrfs_lock_root_node(root);
btrfs_cow_block(trans, root, old, NULL, 0, &old);
@@ -1145,16 +1166,22 @@ int btrfs_commit_transaction_async(struct btrfs_trans_handle *trans,
struct btrfs_transaction *cur_trans;
ac = kmalloc(sizeof(*ac), GFP_NOFS);
- BUG_ON(!ac);
+ if (!ac)
+ return -ENOMEM;
INIT_DELAYED_WORK(&ac->work, do_async_commit);
ac->root = root;
ac->newtrans = btrfs_join_transaction(root, 0);
+ if (IS_ERR(ac->newtrans)) {
+ int err = PTR_ERR(ac->newtrans);
+ kfree(ac);
+ return err;
+ }
/* take transaction reference */
mutex_lock(&root->fs_info->trans_mutex);
cur_trans = trans->transaction;
- cur_trans->use_count++;
+ atomic_inc(&cur_trans->use_count);
mutex_unlock(&root->fs_info->trans_mutex);
btrfs_end_transaction(trans, root);
@@ -1213,7 +1240,7 @@ int btrfs_commit_transaction(struct btrfs_trans_handle *trans,
mutex_lock(&root->fs_info->trans_mutex);
if (cur_trans->in_commit) {
- cur_trans->use_count++;
+ atomic_inc(&cur_trans->use_count);
mutex_unlock(&root->fs_info->trans_mutex);
btrfs_end_transaction(trans, root);
@@ -1235,7 +1262,7 @@ int btrfs_commit_transaction(struct btrfs_trans_handle *trans,
prev_trans = list_entry(cur_trans->list.prev,
struct btrfs_transaction, list);
if (!prev_trans->commit_done) {
- prev_trans->use_count++;
+ atomic_inc(&prev_trans->use_count);
mutex_unlock(&root->fs_info->trans_mutex);
wait_for_commit(root, prev_trans);
@@ -1276,14 +1303,14 @@ int btrfs_commit_transaction(struct btrfs_trans_handle *trans,
TASK_UNINTERRUPTIBLE);
smp_mb();
- if (cur_trans->num_writers > 1)
+ if (atomic_read(&cur_trans->num_writers) > 1)
schedule_timeout(MAX_SCHEDULE_TIMEOUT);
else if (should_grow)
schedule_timeout(1);
mutex_lock(&root->fs_info->trans_mutex);
finish_wait(&cur_trans->writer_wait, &wait);
- } while (cur_trans->num_writers > 1 ||
+ } while (atomic_read(&cur_trans->num_writers) > 1 ||
(should_grow && cur_trans->num_joined != joined));
ret = create_pending_snapshots(trans, root->fs_info);
@@ -1370,9 +1397,12 @@ int btrfs_commit_transaction(struct btrfs_trans_handle *trans,
wake_up(&cur_trans->commit_wait);
+ list_del_init(&cur_trans->list);
put_transaction(cur_trans);
put_transaction(cur_trans);
+ trace_btrfs_transaction_commit(root);
+
mutex_unlock(&root->fs_info->trans_mutex);
if (current->journal_info == trans)
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2025-04-05 22:35:17 +0000