summaryrefslogtreecommitdiffstats
path: root/fs/btrfs/transaction.c
diff options
context:
space:
mode:
Diffstat (limited to 'fs/btrfs/transaction.c')
-rw-r--r--fs/btrfs/transaction.c232
1 files changed, 172 insertions, 60 deletions
diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c
index 2cb1160..66e4c66 100644
--- a/fs/btrfs/transaction.c
+++ b/fs/btrfs/transaction.c
@@ -165,54 +165,89 @@ enum btrfs_trans_type {
TRANS_USERSPACE,
};
+static int may_wait_transaction(struct btrfs_root *root, int type)
+{
+ if (!root->fs_info->log_root_recovering &&
+ ((type == TRANS_START && !root->fs_info->open_ioctl_trans) ||
+ type == TRANS_USERSPACE))
+ return 1;
+ return 0;
+}
+
static struct btrfs_trans_handle *start_transaction(struct btrfs_root *root,
- int num_blocks, int type)
+ u64 num_items, int type)
{
- struct btrfs_trans_handle *h =
- kmem_cache_alloc(btrfs_trans_handle_cachep, GFP_NOFS);
+ struct btrfs_trans_handle *h;
+ struct btrfs_transaction *cur_trans;
+ int retries = 0;
int ret;
+again:
+ h = kmem_cache_alloc(btrfs_trans_handle_cachep, GFP_NOFS);
+ if (!h)
+ return ERR_PTR(-ENOMEM);
mutex_lock(&root->fs_info->trans_mutex);
- if (!root->fs_info->log_root_recovering &&
- ((type == TRANS_START && !root->fs_info->open_ioctl_trans) ||
- type == TRANS_USERSPACE))
+ if (may_wait_transaction(root, type))
wait_current_trans(root);
+
ret = join_transaction(root);
BUG_ON(ret);
- h->transid = root->fs_info->running_transaction->transid;
- h->transaction = root->fs_info->running_transaction;
- h->blocks_reserved = num_blocks;
+ cur_trans = root->fs_info->running_transaction;
+ cur_trans->use_count++;
+ mutex_unlock(&root->fs_info->trans_mutex);
+
+ h->transid = cur_trans->transid;
+ h->transaction = cur_trans;
h->blocks_used = 0;
h->block_group = 0;
- h->alloc_exclude_nr = 0;
- h->alloc_exclude_start = 0;
+ h->bytes_reserved = 0;
h->delayed_ref_updates = 0;
+ h->block_rsv = NULL;
- if (!current->journal_info && type != TRANS_USERSPACE)
- current->journal_info = h;
+ smp_mb();
+ if (cur_trans->blocked && may_wait_transaction(root, type)) {
+ btrfs_commit_transaction(h, root);
+ goto again;
+ }
+
+ if (num_items > 0) {
+ ret = btrfs_trans_reserve_metadata(h, root, num_items,
+ &retries);
+ if (ret == -EAGAIN) {
+ btrfs_commit_transaction(h, root);
+ goto again;
+ }
+ if (ret < 0) {
+ btrfs_end_transaction(h, root);
+ return ERR_PTR(ret);
+ }
+ }
- root->fs_info->running_transaction->use_count++;
+ mutex_lock(&root->fs_info->trans_mutex);
record_root_in_trans(h, root);
mutex_unlock(&root->fs_info->trans_mutex);
+
+ if (!current->journal_info && type != TRANS_USERSPACE)
+ current->journal_info = h;
return h;
}
struct btrfs_trans_handle *btrfs_start_transaction(struct btrfs_root *root,
- int num_blocks)
+ int num_items)
{
- return start_transaction(root, num_blocks, TRANS_START);
+ return start_transaction(root, num_items, TRANS_START);
}
struct btrfs_trans_handle *btrfs_join_transaction(struct btrfs_root *root,
int num_blocks)
{
- return start_transaction(root, num_blocks, TRANS_JOIN);
+ return start_transaction(root, 0, TRANS_JOIN);
}
struct btrfs_trans_handle *btrfs_start_ioctl_transaction(struct btrfs_root *r,
int num_blocks)
{
- return start_transaction(r, num_blocks, TRANS_USERSPACE);
+ return start_transaction(r, 0, TRANS_USERSPACE);
}
/* wait for a transaction commit to be fully complete */
@@ -286,10 +321,36 @@ void btrfs_throttle(struct btrfs_root *root)
mutex_unlock(&root->fs_info->trans_mutex);
}
+static int should_end_transaction(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root)
+{
+ int ret;
+ ret = btrfs_block_rsv_check(trans, root,
+ &root->fs_info->global_block_rsv, 0, 5);
+ return ret ? 1 : 0;
+}
+
+int btrfs_should_end_transaction(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root)
+{
+ struct btrfs_transaction *cur_trans = trans->transaction;
+ int updates;
+
+ if (cur_trans->blocked || cur_trans->delayed_refs.flushing)
+ return 1;
+
+ updates = trans->delayed_ref_updates;
+ trans->delayed_ref_updates = 0;
+ if (updates)
+ btrfs_run_delayed_refs(trans, root, updates);
+
+ return should_end_transaction(trans, root);
+}
+
static int __btrfs_end_transaction(struct btrfs_trans_handle *trans,
struct btrfs_root *root, int throttle)
{
- struct btrfs_transaction *cur_trans;
+ struct btrfs_transaction *cur_trans = trans->transaction;
struct btrfs_fs_info *info = root->fs_info;
int count = 0;
@@ -313,9 +374,21 @@ static int __btrfs_end_transaction(struct btrfs_trans_handle *trans,
count++;
}
+ btrfs_trans_release_metadata(trans, root);
+
+ if (!root->fs_info->open_ioctl_trans &&
+ should_end_transaction(trans, root))
+ trans->transaction->blocked = 1;
+
+ if (cur_trans->blocked && !cur_trans->in_commit) {
+ if (throttle)
+ return btrfs_commit_transaction(trans, root);
+ else
+ wake_up_process(info->transaction_kthread);
+ }
+
mutex_lock(&info->trans_mutex);
- cur_trans = info->running_transaction;
- WARN_ON(cur_trans != trans->transaction);
+ WARN_ON(cur_trans != info->running_transaction);
WARN_ON(cur_trans->num_writers < 1);
cur_trans->num_writers--;
@@ -603,6 +676,7 @@ static noinline int commit_fs_roots(struct btrfs_trans_handle *trans,
btrfs_free_log(trans, root);
btrfs_update_reloc_root(trans, root);
+ btrfs_orphan_commit_root(trans, root);
if (root->commit_root != root->node) {
switch_commit_root(root);
@@ -627,30 +701,30 @@ static noinline int commit_fs_roots(struct btrfs_trans_handle *trans,
int btrfs_defrag_root(struct btrfs_root *root, int cacheonly)
{
struct btrfs_fs_info *info = root->fs_info;
- int ret;
struct btrfs_trans_handle *trans;
+ int ret;
unsigned long nr;
- smp_mb();
- if (root->defrag_running)
+ if (xchg(&root->defrag_running, 1))
return 0;
- trans = btrfs_start_transaction(root, 1);
+
while (1) {
- root->defrag_running = 1;
+ trans = btrfs_start_transaction(root, 0);
+ if (IS_ERR(trans))
+ return PTR_ERR(trans);
+
ret = btrfs_defrag_leaves(trans, root, cacheonly);
+
nr = trans->blocks_used;
btrfs_end_transaction(trans, root);
btrfs_btree_balance_dirty(info->tree_root, nr);
cond_resched();
- trans = btrfs_start_transaction(root, 1);
if (root->fs_info->closing || ret != -EAGAIN)
break;
}
root->defrag_running = 0;
- smp_mb();
- btrfs_end_transaction(trans, root);
- return 0;
+ return ret;
}
#if 0
@@ -758,47 +832,63 @@ static noinline int create_pending_snapshot(struct btrfs_trans_handle *trans,
struct btrfs_root *root = pending->root;
struct btrfs_root *parent_root;
struct inode *parent_inode;
+ struct dentry *dentry;
struct extent_buffer *tmp;
struct extent_buffer *old;
int ret;
- u64 objectid;
- int namelen;
+ int retries = 0;
+ u64 to_reserve = 0;
u64 index = 0;
-
- parent_inode = pending->dentry->d_parent->d_inode;
- parent_root = BTRFS_I(parent_inode)->root;
+ u64 objectid;
new_root_item = kmalloc(sizeof(*new_root_item), GFP_NOFS);
if (!new_root_item) {
- ret = -ENOMEM;
+ pending->error = -ENOMEM;
goto fail;
}
+
ret = btrfs_find_free_objectid(trans, tree_root, 0, &objectid);
- if (ret)
+ if (ret) {
+ pending->error = ret;
goto fail;
+ }
+
+ btrfs_reloc_pre_snapshot(trans, pending, &to_reserve);
+ btrfs_orphan_pre_snapshot(trans, pending, &to_reserve);
+
+ if (to_reserve > 0) {
+ ret = btrfs_block_rsv_add(trans, root, &pending->block_rsv,
+ to_reserve, &retries);
+ if (ret) {
+ pending->error = ret;
+ goto fail;
+ }
+ }
key.objectid = objectid;
- /* record when the snapshot was created in key.offset */
- key.offset = trans->transid;
- btrfs_set_key_type(&key, BTRFS_ROOT_ITEM_KEY);
+ key.offset = (u64)-1;
+ key.type = BTRFS_ROOT_ITEM_KEY;
- memcpy(&pending->root_key, &key, sizeof(key));
- pending->root_key.offset = (u64)-1;
+ trans->block_rsv = &pending->block_rsv;
+ dentry = pending->dentry;
+ parent_inode = dentry->d_parent->d_inode;
+ parent_root = BTRFS_I(parent_inode)->root;
record_root_in_trans(trans, parent_root);
+
/*
* insert the directory item
*/
- namelen = strlen(pending->name);
ret = btrfs_set_inode_index(parent_inode, &index);
BUG_ON(ret);
ret = btrfs_insert_dir_item(trans, parent_root,
- pending->name, namelen,
- parent_inode->i_ino,
- &pending->root_key, BTRFS_FT_DIR, index);
+ dentry->d_name.name, dentry->d_name.len,
+ parent_inode->i_ino, &key,
+ BTRFS_FT_DIR, index);
BUG_ON(ret);
- btrfs_i_size_write(parent_inode, parent_inode->i_size + namelen * 2);
+ btrfs_i_size_write(parent_inode, parent_inode->i_size +
+ dentry->d_name.len * 2);
ret = btrfs_update_inode(trans, parent_root, parent_inode);
BUG_ON(ret);
@@ -815,22 +905,32 @@ static noinline int create_pending_snapshot(struct btrfs_trans_handle *trans,
free_extent_buffer(old);
btrfs_set_root_node(new_root_item, tmp);
- ret = btrfs_insert_root(trans, root->fs_info->tree_root, &key,
- new_root_item);
- BUG_ON(ret);
+ /* record when the snapshot was created in key.offset */
+ key.offset = trans->transid;
+ ret = btrfs_insert_root(trans, tree_root, &key, new_root_item);
btrfs_tree_unlock(tmp);
free_extent_buffer(tmp);
+ BUG_ON(ret);
- ret = btrfs_add_root_ref(trans, parent_root->fs_info->tree_root,
- pending->root_key.objectid,
+ /*
+ * insert root back/forward references
+ */
+ ret = btrfs_add_root_ref(trans, tree_root, objectid,
parent_root->root_key.objectid,
- parent_inode->i_ino, index, pending->name,
- namelen);
+ parent_inode->i_ino, index,
+ dentry->d_name.name, dentry->d_name.len);
BUG_ON(ret);
+ key.offset = (u64)-1;
+ pending->snap = btrfs_read_fs_root_no_name(root->fs_info, &key);
+ BUG_ON(IS_ERR(pending->snap));
+
+ btrfs_reloc_post_snapshot(trans, pending);
+ btrfs_orphan_post_snapshot(trans, pending);
fail:
kfree(new_root_item);
- return ret;
+ btrfs_block_rsv_release(root, &pending->block_rsv, (u64)-1);
+ return 0;
}
/*
@@ -878,6 +978,16 @@ int btrfs_transaction_in_commit(struct btrfs_fs_info *info)
return ret;
}
+int btrfs_transaction_blocked(struct btrfs_fs_info *info)
+{
+ int ret = 0;
+ spin_lock(&info->new_trans_lock);
+ if (info->running_transaction)
+ ret = info->running_transaction->blocked;
+ spin_unlock(&info->new_trans_lock);
+ return ret;
+}
+
int btrfs_commit_transaction(struct btrfs_trans_handle *trans,
struct btrfs_root *root)
{
@@ -899,6 +1009,8 @@ int btrfs_commit_transaction(struct btrfs_trans_handle *trans,
ret = btrfs_run_delayed_refs(trans, root, 0);
BUG_ON(ret);
+ btrfs_trans_release_metadata(trans, root);
+
cur_trans = trans->transaction;
/*
* set the flushing flag so procs in this transaction have to
@@ -951,9 +1063,6 @@ int btrfs_commit_transaction(struct btrfs_trans_handle *trans,
snap_pending = 1;
WARN_ON(cur_trans != trans->transaction);
- prepare_to_wait(&cur_trans->writer_wait, &wait,
- TASK_UNINTERRUPTIBLE);
-
if (cur_trans->num_writers > 1)
timeout = MAX_SCHEDULE_TIMEOUT;
else if (should_grow)
@@ -976,6 +1085,9 @@ int btrfs_commit_transaction(struct btrfs_trans_handle *trans,
*/
btrfs_run_ordered_operations(root, 1);
+ prepare_to_wait(&cur_trans->writer_wait, &wait,
+ TASK_UNINTERRUPTIBLE);
+
smp_mb();
if (cur_trans->num_writers > 1 || should_grow)
schedule_timeout(timeout);
@@ -1103,9 +1215,9 @@ int btrfs_clean_old_snapshots(struct btrfs_root *root)
if (btrfs_header_backref_rev(root->node) <
BTRFS_MIXED_BACKREF_REV)
- btrfs_drop_snapshot(root, 0);
+ btrfs_drop_snapshot(root, NULL, 0);
else
- btrfs_drop_snapshot(root, 1);
+ btrfs_drop_snapshot(root, NULL, 1);
}
return 0;
}
OpenPOWER on IntegriCloud