Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
Merge branch 'for-linus-4.7-part2' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs
Pull btrfs fixes part 2 from Chris Mason:
"This has one patch from Omar to bring iterate_shared back to btrfs.
We have a tree of work we queue up for directory items and it doesn't
lend itself well to shared access. While we're cleaning it up, Omar
has changed things to use an exclusive lock when there are delayed
items"
* 'for-linus-4.7-part2' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
Btrfs: fix ->iterate_shared() by upgrading i_rwsem for delayed nodes
+34
-13
+22
-5
fs/btrfs/delayed-inode.c
+22
-5
fs/btrfs/delayed-inode.c
···
1606
1606
return 0;
1607
1607
}
1608
1608
1609
-
void btrfs_get_delayed_items(struct inode *inode, struct list_head *ins_list,
1610
-
struct list_head *del_list)
1609
+
bool btrfs_readdir_get_delayed_items(struct inode *inode,
1610
+
struct list_head *ins_list,
1611
+
struct list_head *del_list)
1611
1612
{
1612
1613
struct btrfs_delayed_node *delayed_node;
1613
1614
struct btrfs_delayed_item *item;
1614
1615
1615
1616
delayed_node = btrfs_get_delayed_node(inode);
1616
1617
if (!delayed_node)
1617
-
return;
1618
+
return false;
1619
+
1620
+
/*
1621
+
* We can only do one readdir with delayed items at a time because of
1622
+
* item->readdir_list.
1623
+
*/
1624
+
inode_unlock_shared(inode);
1625
+
inode_lock(inode);
1618
1626
1619
1627
mutex_lock(&delayed_node->mutex);
1620
1628
item = __btrfs_first_delayed_insertion_item(delayed_node);
···
1649
1641
* requeue or dequeue this delayed node.
1650
1642
*/
1651
1643
atomic_dec(&delayed_node->refs);
1644
+
1645
+
return true;
1652
1646
}
1653
1647
1654
-
void btrfs_put_delayed_items(struct list_head *ins_list,
1655
-
struct list_head *del_list)
1648
+
void btrfs_readdir_put_delayed_items(struct inode *inode,
1649
+
struct list_head *ins_list,
1650
+
struct list_head *del_list)
1656
1651
{
1657
1652
struct btrfs_delayed_item *curr, *next;
1658
1653
···
1670
1659
if (atomic_dec_and_test(&curr->refs))
1671
1660
kfree(curr);
1672
1661
}
1662
+
1663
+
/*
1664
+
* The VFS is going to do up_read(), so we need to downgrade back to a
1665
+
* read lock.
1666
+
*/
1667
+
downgrade_write(&inode->i_rwsem);
1673
1668
}
1674
1669
1675
1670
int btrfs_should_delete_dir_index(struct list_head *del_list,
+6
-4
fs/btrfs/delayed-inode.h
+6
-4
fs/btrfs/delayed-inode.h
···
137
137
void btrfs_destroy_delayed_inodes(struct btrfs_root *root);
138
138
139
139
/* Used for readdir() */
140
-
void btrfs_get_delayed_items(struct inode *inode, struct list_head *ins_list,
141
-
struct list_head *del_list);
142
-
void btrfs_put_delayed_items(struct list_head *ins_list,
143
-
struct list_head *del_list);
140
+
bool btrfs_readdir_get_delayed_items(struct inode *inode,
141
+
struct list_head *ins_list,
142
+
struct list_head *del_list);
143
+
void btrfs_readdir_put_delayed_items(struct inode *inode,
144
+
struct list_head *ins_list,
145
+
struct list_head *del_list);
144
146
int btrfs_should_delete_dir_index(struct list_head *del_list,
145
147
u64 index);
146
148
int btrfs_readdir_delayed_dir_index(struct dir_context *ctx,
+6
-4
fs/btrfs/inode.c
+6
-4
fs/btrfs/inode.c
···
5758
5758
int name_len;
5759
5759
int is_curr = 0; /* ctx->pos points to the current index? */
5760
5760
bool emitted;
5761
+
bool put = false;
5761
5762
5762
5763
/* FIXME, use a real flag for deciding about the key type */
5763
5764
if (root->fs_info->tree_root == root)
···
5776
5775
if (key_type == BTRFS_DIR_INDEX_KEY) {
5777
5776
INIT_LIST_HEAD(&ins_list);
5778
5777
INIT_LIST_HEAD(&del_list);
5779
-
btrfs_get_delayed_items(inode, &ins_list, &del_list);
5778
+
put = btrfs_readdir_get_delayed_items(inode, &ins_list,
5779
+
&del_list);
5780
5780
}
5781
5781
5782
5782
key.type = key_type;
···
5924
5922
nopos:
5925
5923
ret = 0;
5926
5924
err:
5927
-
if (key_type == BTRFS_DIR_INDEX_KEY)
5928
-
btrfs_put_delayed_items(&ins_list, &del_list);
5925
+
if (put)
5926
+
btrfs_readdir_put_delayed_items(inode, &ins_list, &del_list);
5929
5927
btrfs_free_path(path);
5930
5928
return ret;
5931
5929
}
···
10537
10535
static const struct file_operations btrfs_dir_file_operations = {
10538
10536
.llseek = generic_file_llseek,
10539
10537
.read = generic_read_dir,
10540
-
.iterate = btrfs_real_readdir,
10538
+
.iterate_shared = btrfs_real_readdir,
10541
10539
.unlocked_ioctl = btrfs_ioctl,
10542
10540
#ifdef CONFIG_COMPAT
10543
10541
.compat_ioctl = btrfs_compat_ioctl,