Commit bb47cce7 authored by Andreas Gruenbacher's avatar Andreas Gruenbacher
Browse files

gfs2: gfs2_log_flush withdraw fixes 



When a withdraw occurs in gfs2_log_flush() and we are left with an unsubmitted
bio, fail that bio.  Otherwise, the bh's in that bio will remain locked and
gfs2_evict_inode() -> truncate_inode_pages() -> gfs2_invalidate_folio() ->
gfs2_discard() will hang trying to discard the locked bh's.

In addition, when gfs2_log_flush() fails to submit a new transaction, unpin the
buffers in the failing transaction like gfs2_remove_from_journal() does.  If
any of the bd's are on the ail2 list, leave them there and do_withdraw() ->
gfs2_withdraw_glocks() -> inode_go_inval() -> truncate_inode_pages() ->
gfs2_invalidate_folio() -> gfs2_discard() will remove them.  They will be freed
in gfs2_release_folio().

Signed-off-by: default avatarAndreas Gruenbacher <agruenba@redhat.com>
parent fe2c8d05

fs/gfs2/log.c

+17 −8
Original line number Diff line number Diff line
@@ -983,33 +983,38 @@ static void empty_ail1_list(struct gfs2_sbd *sdp) 
	}

}



static void gfs2_trans_drain_list(struct list_head *list)

static void gfs2_trans_drain_list(struct gfs2_sbd *sdp, struct list_head *list)

{

	struct gfs2_bufdata *bd;



	while (!list_empty(list)) {

		bd = list_first_entry(list, struct gfs2_bufdata, bd_list);

		struct buffer_head *bh = bd->bd_bh;



		WARN_ON_ONCE(!buffer_pinned(bh));

		clear_buffer_pinned(bh);

		trace_gfs2_pin(bd, 0);

		atomic_dec(&sdp->sd_log_pinned);

		list_del_init(&bd->bd_list);

		if (!list_empty(&bd->bd_ail_st_list))

			gfs2_remove_from_ail(bd);

		kmem_cache_free(gfs2_bufdata_cachep, bd);

		brelse(bh);

	}

}



/**

 * gfs2_trans_drain - drain the buf and databuf queue for a failed transaction

 * @sdp: the filesystem

 * @tr: the transaction to drain

 *

 * When this is called, we're taking an error exit for a log write that failed

 * but since we bypassed the after_commit functions, we need to remove the

 * items from the buf and databuf queue.

 */

static void gfs2_trans_drain(struct gfs2_trans *tr)

static void gfs2_trans_drain(struct gfs2_sbd *sdp, struct gfs2_trans *tr)

{

	if (!tr)

		return;

	gfs2_trans_drain_list(&tr->tr_buf);

	gfs2_trans_drain_list(&tr->tr_databuf);

	gfs2_trans_drain_list(sdp, &tr->tr_buf);

	gfs2_trans_drain_list(sdp, &tr->tr_databuf);

}



void gfs2_remove_from_journal(struct buffer_head *bh, int meta)
@@ -1185,7 +1190,11 @@ static void __gfs2_log_flush(struct gfs2_sbd *sdp, struct gfs2_glock *gl, 
	return;



out_withdraw:

	gfs2_trans_drain(tr);

	if (sdp->sd_jdesc->jd_log_bio) {

		bio_io_error(sdp->sd_jdesc->jd_log_bio);

		sdp->sd_jdesc->jd_log_bio = NULL;

	}

	gfs2_trans_drain(sdp, tr);

	/**

	 * If the tr_list is empty, we're withdrawing during a log

	 * flush that targets a transaction, but the transaction was