From 4f1de018215fb56940ce5793e11becd1e8cd6e44 Mon Sep 17 00:00:00 2001 From: Steven Whitehouse Date: Tue, 26 Apr 2011 10:23:56 +0100 Subject: GFS2: Fix ail list traversal In the recent patches to update the AIL list code, I managed to forget that the ail list lock got dropped, even though I added a comment specifically to remind myself :( Reported-by: Barry Marson Signed-off-by: Steven Whitehouse --- fs/gfs2/log.c | 17 +++++++++++------ 1 file changed, 11 insertions(+), 6 deletions(-) (limited to 'fs') diff --git a/fs/gfs2/log.c b/fs/gfs2/log.c index ad1f1887633f..cec26c00b50d 100644 --- a/fs/gfs2/log.c +++ b/fs/gfs2/log.c @@ -89,9 +89,9 @@ void gfs2_remove_from_ail(struct gfs2_bufdata *bd) * */ -static void gfs2_ail1_start_one(struct gfs2_sbd *sdp, - struct writeback_control *wbc, - struct gfs2_ail *ai) +static int gfs2_ail1_start_one(struct gfs2_sbd *sdp, + struct writeback_control *wbc, + struct gfs2_ail *ai) __releases(&sdp->sd_ail_lock) __acquires(&sdp->sd_ail_lock) { @@ -100,7 +100,6 @@ __acquires(&sdp->sd_ail_lock) struct gfs2_bufdata *bd, *s; struct buffer_head *bh; -restart: list_for_each_entry_safe_reverse(bd, s, &ai->ai_ail1_list, bd_ail_st_list) { bh = bd->bd_bh; @@ -120,13 +119,17 @@ restart: gl = bd->bd_gl; list_move(&bd->bd_ail_st_list, &ai->ai_ail1_list); mapping = bh->b_page->mapping; + if (!mapping) + continue; spin_unlock(&sdp->sd_ail_lock); generic_writepages(mapping, wbc); spin_lock(&sdp->sd_ail_lock); if (wbc->nr_to_write <= 0) break; - goto restart; + return 1; } + + return 0; } @@ -146,10 +149,12 @@ void gfs2_ail1_flush(struct gfs2_sbd *sdp, struct writeback_control *wbc) trace_gfs2_ail_flush(sdp, wbc, 1); spin_lock(&sdp->sd_ail_lock); +restart: list_for_each_entry_reverse(ai, head, ai_list) { if (wbc->nr_to_write <= 0) break; - gfs2_ail1_start_one(sdp, wbc, ai); /* This may drop ail lock */ + if (gfs2_ail1_start_one(sdp, wbc, ai)) + goto restart; } spin_unlock(&sdp->sd_ail_lock); trace_gfs2_ail_flush(sdp, wbc, 0); -- cgit v1.2.2