aboutsummaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
authorSteven Whitehouse <swhiteho@redhat.com>2011-05-03 06:49:19 -0400
committerSteven Whitehouse <swhiteho@redhat.com>2011-05-03 06:49:19 -0400
commit8f065d36508f283ee6cbeb05829f032d0b782a16 (patch)
tree3ebd2a660a5d13c773e16c024ce025df24a9b502
parent4f1de018215fb56940ce5793e11becd1e8cd6e44 (diff)
GFS2: Improve bug trap code in ->releasepage()
If the buffer is dirty or pinned, then as well as printing a warning, we should also refuse to release the page in question. Currently this can occur if there is a race between mmap()ed writers and O_DIRECT on the same file. With the addition of ->launder_page() in the future, we should be able to close this gap. Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
-rw-r--r--fs/gfs2/aops.c8
1 files changed, 6 insertions, 2 deletions
diff --git a/fs/gfs2/aops.c b/fs/gfs2/aops.c
index 0f5c4f9d5d62..802ac5eeba28 100644
--- a/fs/gfs2/aops.c
+++ b/fs/gfs2/aops.c
@@ -1076,8 +1076,8 @@ int gfs2_releasepage(struct page *page, gfp_t gfp_mask)
1076 bd = bh->b_private; 1076 bd = bh->b_private;
1077 if (bd && bd->bd_ail) 1077 if (bd && bd->bd_ail)
1078 goto cannot_release; 1078 goto cannot_release;
1079 gfs2_assert_warn(sdp, !buffer_pinned(bh)); 1079 if (buffer_pinned(bh) || buffer_dirty(bh))
1080 gfs2_assert_warn(sdp, !buffer_dirty(bh)); 1080 goto not_possible;
1081 bh = bh->b_this_page; 1081 bh = bh->b_this_page;
1082 } while(bh != head); 1082 } while(bh != head);
1083 gfs2_log_unlock(sdp); 1083 gfs2_log_unlock(sdp);
@@ -1107,6 +1107,10 @@ int gfs2_releasepage(struct page *page, gfp_t gfp_mask)
1107 } while (bh != head); 1107 } while (bh != head);
1108 1108
1109 return try_to_free_buffers(page); 1109 return try_to_free_buffers(page);
1110
1111not_possible: /* Should never happen */
1112 WARN_ON(buffer_dirty(bh));
1113 WARN_ON(buffer_pinned(bh));
1110cannot_release: 1114cannot_release:
1111 gfs2_log_unlock(sdp); 1115 gfs2_log_unlock(sdp);
1112 return 0; 1116 return 0;