Btrfs: Replace the big fs_mutex with a collection of other locks
Extent alloctions are still protected by a large alloc_mutex.
Objectid allocations are covered by a objectid mutex
Other btree operations are protected by a lock on individual btree nodes
Signed-off-by: Chris Mason <chris.mason@oracle.com>
diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index 3fbf74e..6002eb6 100644
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -63,7 +63,6 @@
u64 new_dirid = BTRFS_FIRST_FREE_OBJECTID;
unsigned long nr = 1;
- mutex_lock(&root->fs_info->fs_mutex);
ret = btrfs_check_free_space(root, 1, 0);
if (ret)
goto fail_commit;
@@ -164,7 +163,6 @@
if (err && !ret)
ret = err;
fail_commit:
- mutex_unlock(&root->fs_info->fs_mutex);
btrfs_btree_balance_dirty(root, nr);
btrfs_throttle(root);
return ret;
@@ -181,7 +179,6 @@
if (!root->ref_cows)
return -EINVAL;
- mutex_lock(&root->fs_info->fs_mutex);
ret = btrfs_check_free_space(root, 1, 0);
if (ret)
goto fail_unlock;
@@ -208,7 +205,6 @@
err = btrfs_commit_transaction(trans, root);
fail_unlock:
- mutex_unlock(&root->fs_info->fs_mutex);
btrfs_btree_balance_dirty(root, nr);
btrfs_throttle(root);
return ret;
@@ -228,9 +224,7 @@
unsigned long i;
int ret;
- mutex_lock(&root->fs_info->fs_mutex);
ret = btrfs_check_free_space(root, inode->i_size, 0);
- mutex_unlock(&root->fs_info->fs_mutex);
if (ret)
return -ENOSPC;
@@ -315,7 +309,8 @@
goto out;
}
- mutex_lock(&root->fs_info->fs_mutex);
+ mutex_lock(&root->fs_info->alloc_mutex);
+ mutex_lock(&root->fs_info->chunk_mutex);
sizestr = vol_args->name;
devstr = strchr(sizestr, ':');
if (devstr) {
@@ -385,7 +380,8 @@
}
out_unlock:
- mutex_unlock(&root->fs_info->fs_mutex);
+ mutex_lock(&root->fs_info->alloc_mutex);
+ mutex_lock(&root->fs_info->chunk_mutex);
out:
kfree(vol_args);
return ret;
@@ -428,11 +424,9 @@
}
root_dirid = root->fs_info->sb->s_root->d_inode->i_ino,
- mutex_lock(&root->fs_info->fs_mutex);
di = btrfs_lookup_dir_item(NULL, root->fs_info->tree_root,
path, root_dirid,
vol_args->name, namelen, 0);
- mutex_unlock(&root->fs_info->fs_mutex);
btrfs_free_path(path);
if (di && !IS_ERR(di)) {
@@ -445,10 +439,12 @@
goto out;
}
+ mutex_lock(&root->fs_info->drop_mutex);
if (root == root->fs_info->tree_root)
ret = create_subvol(root, vol_args->name, namelen);
else
ret = create_snapshot(root, vol_args->name, namelen);
+ mutex_unlock(&root->fs_info->drop_mutex);
out:
kfree(vol_args);
return ret;
@@ -461,10 +457,8 @@
switch (inode->i_mode & S_IFMT) {
case S_IFDIR:
- mutex_lock(&root->fs_info->fs_mutex);
btrfs_defrag_root(root, 0);
btrfs_defrag_root(root->fs_info->extent_root, 0);
- mutex_unlock(&root->fs_info->fs_mutex);
break;
case S_IFREG:
btrfs_defrag_file(file);
@@ -588,7 +582,6 @@
unlock_extent(&BTRFS_I(src)->io_tree, 0, (u64)-1, GFP_NOFS);
}
- mutex_lock(&root->fs_info->fs_mutex);
trans = btrfs_start_transaction(root, 0);
path = btrfs_alloc_path();
if (!path) {
@@ -685,7 +678,6 @@
unlock_extent(&BTRFS_I(src)->io_tree, 0, (u64)-1, GFP_NOFS);
btrfs_end_transaction(trans, root);
- mutex_unlock(&root->fs_info->fs_mutex);
out_unlock:
mutex_unlock(&src->i_mutex);
@@ -711,7 +703,6 @@
if (!capable(CAP_SYS_ADMIN))
return -EPERM;
- mutex_lock(&root->fs_info->fs_mutex);
if (file->private_data) {
ret = -EINPROGRESS;
goto out;
@@ -723,7 +714,6 @@
ret = -ENOMEM;
/*printk(KERN_INFO "btrfs_ioctl_trans_start on %p\n", file);*/
out:
- mutex_unlock(&root->fs_info->fs_mutex);
return ret;
}
@@ -740,7 +730,6 @@
struct btrfs_trans_handle *trans;
int ret = 0;
- mutex_lock(&root->fs_info->fs_mutex);
trans = file->private_data;
if (!trans) {
ret = -EINVAL;
@@ -749,7 +738,6 @@
btrfs_end_transaction(trans, root);
file->private_data = 0;
out:
- mutex_unlock(&root->fs_info->fs_mutex);
return ret;
}