aboutsummaryrefslogtreecommitdiff
path: root/fs
diff options
context:
space:
mode:
authorChris Mason <chris.mason@oracle.com>2011-11-01 10:08:06 -0400
committerChris Mason <chris.mason@oracle.com>2011-11-06 03:03:48 -0500
commit01d658f2ca3c85c1ffb20b306e30d16197000ce7 (patch)
treeeda62586bb95967a4001f8fb70e6955b531cf801 /fs
parente688b7252f784c2479d559f9f70ca8354752c5e7 (diff)
downloadlinux-stericsson-01d658f2ca3c85c1ffb20b306e30d16197000ce7.tar.gz
Btrfs: make sure to flush queued bios if write_cache_pages waits
write_cache_pages tries to build up a large bio to stuff down the pipe. But if it needs to wait for a page lock, it needs to make sure and send down any pending writes so we don't deadlock with anyone who has the page lock and is waiting for writeback of things inside the bio. Dave Sterba triggered this as a deadlock between the autodefrag code and the extent write_cache_pages Signed-off-by: Chris Mason <chris.mason@oracle.com>
Diffstat (limited to 'fs')
-rw-r--r--fs/btrfs/disk-io.c13
-rw-r--r--fs/btrfs/disk-io.h2
-rw-r--r--fs/btrfs/extent_io.c14
-rw-r--r--fs/btrfs/extent_io.h3
4 files changed, 22 insertions, 10 deletions
diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index 51372a521167..6f58911ece0d 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -2735,7 +2735,8 @@ int btrfs_read_buffer(struct extent_buffer *buf, u64 parent_transid)
return ret;
}
-int btree_lock_page_hook(struct page *page)
+static int btree_lock_page_hook(struct page *page, void *data,
+ void (*flush_fn)(void *))
{
struct inode *inode = page->mapping->host;
struct btrfs_root *root = BTRFS_I(inode)->root;
@@ -2752,7 +2753,10 @@ int btree_lock_page_hook(struct page *page)
if (!eb)
goto out;
- btrfs_tree_lock(eb);
+ if (!btrfs_try_tree_write_lock(eb)) {
+ flush_fn(data);
+ btrfs_tree_lock(eb);
+ }
btrfs_set_header_flag(eb, BTRFS_HEADER_FLAG_WRITTEN);
if (test_and_clear_bit(EXTENT_BUFFER_DIRTY, &eb->bflags)) {
@@ -2767,7 +2771,10 @@ int btree_lock_page_hook(struct page *page)
btrfs_tree_unlock(eb);
free_extent_buffer(eb);
out:
- lock_page(page);
+ if (!trylock_page(page)) {
+ flush_fn(data);
+ lock_page(page);
+ }
return 0;
}
diff --git a/fs/btrfs/disk-io.h b/fs/btrfs/disk-io.h
index bec3ea4bd67f..e678539c8519 100644
--- a/fs/btrfs/disk-io.h
+++ b/fs/btrfs/disk-io.h
@@ -83,8 +83,6 @@ int btrfs_init_log_root_tree(struct btrfs_trans_handle *trans,
struct btrfs_fs_info *fs_info);
int btrfs_add_log_tree(struct btrfs_trans_handle *trans,
struct btrfs_root *root);
-int btree_lock_page_hook(struct page *page);
-
#ifdef CONFIG_DEBUG_LOCK_ALLOC
void btrfs_init_lockdep(void);
diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c
index f284d4e5f447..b40ba75f4483 100644
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -2613,10 +2613,16 @@ retry:
* swizzled back from swapper_space to tmpfs file
* mapping
*/
- if (tree->ops && tree->ops->write_cache_pages_lock_hook)
- tree->ops->write_cache_pages_lock_hook(page);
- else
- lock_page(page);
+ if (tree->ops &&
+ tree->ops->write_cache_pages_lock_hook) {
+ tree->ops->write_cache_pages_lock_hook(page,
+ data, flush_fn);
+ } else {
+ if (!trylock_page(page)) {
+ flush_fn(data);
+ lock_page(page);
+ }
+ }
if (unlikely(page->mapping != mapping)) {
unlock_page(page);
diff --git a/fs/btrfs/extent_io.h b/fs/btrfs/extent_io.h
index 325a346369da..cbd4824a7c94 100644
--- a/fs/btrfs/extent_io.h
+++ b/fs/btrfs/extent_io.h
@@ -86,7 +86,8 @@ struct extent_io_ops {
struct extent_state *other);
void (*split_extent_hook)(struct inode *inode,
struct extent_state *orig, u64 split);
- int (*write_cache_pages_lock_hook)(struct page *page);
+ int (*write_cache_pages_lock_hook)(struct page *page, void *data,
+ void (*flush_fn)(void *));
};
struct extent_io_tree {