diff options
author | Sage Weil <sage@newdream.net> | 2010-04-01 09:01:38 +0400 |
---|---|---|
committer | Sage Weil <sage@newdream.net> | 2010-04-01 20:34:37 +0400 |
commit | 6298a33757ba7361bb8f506c106daad77e5ac8cf (patch) | |
tree | ebd8e7cab86a66c00c0bd4f411c335ed4d0fda9f /fs | |
parent | 80e755fedebc8de0599a79efad2c656503df2e62 (diff) | |
download | linux-6298a33757ba7361bb8f506c106daad77e5ac8cf.tar.xz |
ceph: fix snap context reference leaks
The get_oldest_context() helper takes a reference to the returned snap
context, but most callers weren't dropping that reference. Fix them.
Also drop the unused locked __get_oldest_context() variant.
Signed-off-by: Sage Weil <sage@newdream.net>
Diffstat (limited to 'fs')
-rw-r--r-- | fs/ceph/addr.c | 37 |
1 files changed, 17 insertions, 20 deletions
diff --git a/fs/ceph/addr.c b/fs/ceph/addr.c index a313e9baeed0..41f1f713b7ba 100644 --- a/fs/ceph/addr.c +++ b/fs/ceph/addr.c @@ -336,16 +336,15 @@ out: /* * Get ref for the oldest snapc for an inode with dirty data... that is, the * only snap context we are allowed to write back. - * - * Caller holds i_lock. */ -static struct ceph_snap_context *__get_oldest_context(struct inode *inode, - u64 *snap_size) +static struct ceph_snap_context *get_oldest_context(struct inode *inode, + u64 *snap_size) { struct ceph_inode_info *ci = ceph_inode(inode); struct ceph_snap_context *snapc = NULL; struct ceph_cap_snap *capsnap = NULL; + spin_lock(&inode->i_lock); list_for_each_entry(capsnap, &ci->i_cap_snaps, ci_item) { dout(" cap_snap %p snapc %p has %d dirty pages\n", capsnap, capsnap->context, capsnap->dirty_pages); @@ -361,16 +360,6 @@ static struct ceph_snap_context *__get_oldest_context(struct inode *inode, dout(" head snapc %p has %d dirty pages\n", snapc, ci->i_wrbuffer_ref_head); } - return snapc; -} - -static struct ceph_snap_context *get_oldest_context(struct inode *inode, - u64 *snap_size) -{ - struct ceph_snap_context *snapc = NULL; - - spin_lock(&inode->i_lock); - snapc = __get_oldest_context(inode, snap_size); spin_unlock(&inode->i_lock); return snapc; } @@ -391,7 +380,7 @@ static int writepage_nounlock(struct page *page, struct writeback_control *wbc) int len = PAGE_CACHE_SIZE; loff_t i_size; int err = 0; - struct ceph_snap_context *snapc; + struct ceph_snap_context *snapc, *oldest; u64 snap_size = 0; long writeback_stat; @@ -412,13 +401,16 @@ static int writepage_nounlock(struct page *page, struct writeback_control *wbc) dout("writepage %p page %p not dirty?\n", inode, page); goto out; } - if (snapc->seq > get_oldest_context(inode, &snap_size)->seq) { + oldest = get_oldest_context(inode, &snap_size); + if (snapc->seq > oldest->seq) { dout("writepage %p page %p snapc %p not writeable - noop\n", inode, page, (void *)page->private); /* we should only noop if called by kswapd */ WARN_ON((current->flags & PF_MEMALLOC) == 0); + ceph_put_snap_context(oldest); goto out; } + ceph_put_snap_context(oldest); /* is this a partial page at end of file? */ if (snap_size) @@ -457,7 +449,7 @@ static int writepage_nounlock(struct page *page, struct writeback_control *wbc) ClearPagePrivate(page); end_page_writeback(page); ceph_put_wrbuffer_cap_refs(ci, 1, snapc); - ceph_put_snap_context(snapc); + ceph_put_snap_context(snapc); /* page's reference */ out: return err; } @@ -914,7 +906,10 @@ static int context_is_writeable_or_written(struct inode *inode, struct ceph_snap_context *snapc) { struct ceph_snap_context *oldest = get_oldest_context(inode, NULL); - return !oldest || snapc->seq <= oldest->seq; + int ret = !oldest || snapc->seq <= oldest->seq; + + ceph_put_snap_context(oldest); + return ret; } /* @@ -957,13 +952,14 @@ retry_locked: up_read(&mdsc->snap_rwsem); if (snapc->seq > oldest->seq) { + ceph_put_snap_context(oldest); dout(" page %p snapc %p not current or oldest\n", - page, (void *)page->private); + page, snapc); /* * queue for writeback, and wait for snapc to * be writeable or written */ - snapc = ceph_get_snap_context((void *)page->private); + snapc = ceph_get_snap_context(snapc); unlock_page(page); ceph_queue_writeback(inode); r = wait_event_interruptible(ci->i_cap_wq, @@ -973,6 +969,7 @@ retry_locked: return r; return -EAGAIN; } + ceph_put_snap_context(oldest); /* yay, writeable, do it now (without dropping page lock) */ dout(" page %p snapc %p not current, but oldest\n", |