From 942b0cddfbf66295effc9fd879ca85ae10638565 Mon Sep 17 00:00:00 2001 From: Bob Peterson Date: Wed, 16 Aug 2017 11:30:06 -0500 Subject: [PATCH] GFS2: Withdraw for IO errors writing to the journal or statfs Before this patch, if GFS2 encountered IO errors while writing to the journal, it would not report the problem, so they would go unnoticed, sometimes for many hours. Sometimes this would only be noticed later, when recovery tried to do journal replay and failed due to invalid metadata at the blocks that resulted in IO errors. This patch makes GFS2's log daemon check for IO errors. If it encounters one, it withdraws from the file system and reports why in dmesg. A similar action is taken when IO errors occur when writing to the system statfs file. These errors are also reported back to any callers of fsync, since that requires the journal to be flushed. Therefore, any IO errors that would previously go unnoticed are now noticed and the file system is withdrawn as early as possible, thus preventing further file system damage. Also note that this reintroduces superblock variable sd_log_error, which Christoph removed with commit f729b66fca. Signed-off-by: Bob Peterson --- fs/gfs2/incore.h | 1 + fs/gfs2/log.c | 9 +++++++++ fs/gfs2/lops.c | 7 +++++-- fs/gfs2/quota.c | 5 ++++- fs/gfs2/super.c | 4 ++-- 5 files changed, 21 insertions(+), 5 deletions(-) diff --git a/fs/gfs2/incore.h b/fs/gfs2/incore.h index a7b0331c549d..0ce0b334f412 100644 --- a/fs/gfs2/incore.h +++ b/fs/gfs2/incore.h @@ -817,6 +817,7 @@ struct gfs2_sbd { atomic_t sd_log_in_flight; struct bio *sd_log_bio; wait_queue_head_t sd_log_flush_wait; + int sd_log_error; atomic_t sd_reserving_log; wait_queue_head_t sd_reserving_log_wait; diff --git a/fs/gfs2/log.c b/fs/gfs2/log.c index 31585c2d22fe..f72c44231406 100644 --- a/fs/gfs2/log.c +++ b/fs/gfs2/log.c @@ -923,6 +923,15 @@ int gfs2_logd(void *data) while (!kthread_should_stop()) { + /* Check for errors writing to the journal */ + if (sdp->sd_log_error) { + gfs2_lm_withdraw(sdp, + "GFS2: fsid=%s: error %d: " + "withdrawing the file system to " + "prevent further damage.\n", + sdp->sd_fsname, sdp->sd_log_error); + } + did_flush = false; if (gfs2_jrnl_flush_reqd(sdp) || t == 0) { gfs2_ail1_empty(sdp); diff --git a/fs/gfs2/lops.c b/fs/gfs2/lops.c index 3010f9edd177..7dabbe721dba 100644 --- a/fs/gfs2/lops.c +++ b/fs/gfs2/lops.c @@ -207,8 +207,11 @@ static void gfs2_end_log_write(struct bio *bio) struct page *page; int i; - if (bio->bi_status) - fs_err(sdp, "Error %d writing to log\n", bio->bi_status); + if (bio->bi_status) { + fs_err(sdp, "Error %d writing to journal, jid=%u\n", + bio->bi_status, sdp->sd_jdesc->jd_jid); + wake_up(&sdp->sd_logd_waitq); + } bio_for_each_segment_all(bvec, bio, i) { page = bvec->bv_page; diff --git a/fs/gfs2/quota.c b/fs/gfs2/quota.c index 739adf105d7f..e647938432bd 100644 --- a/fs/gfs2/quota.c +++ b/fs/gfs2/quota.c @@ -1474,8 +1474,11 @@ static void quotad_error(struct gfs2_sbd *sdp, const char *msg, int error) { if (error == 0 || error == -EROFS) return; - if (!test_bit(SDF_SHUTDOWN, &sdp->sd_flags)) + if (!test_bit(SDF_SHUTDOWN, &sdp->sd_flags)) { fs_err(sdp, "gfs2_quotad: %s error %d\n", msg, error); + sdp->sd_log_error = error; + wake_up(&sdp->sd_logd_waitq); + } } static void quotad_check_timeo(struct gfs2_sbd *sdp, const char *msg, diff --git a/fs/gfs2/super.c b/fs/gfs2/super.c index a83fe8260d2e..769841185ce5 100644 --- a/fs/gfs2/super.c +++ b/fs/gfs2/super.c @@ -944,9 +944,9 @@ static int gfs2_sync_fs(struct super_block *sb, int wait) struct gfs2_sbd *sdp = sb->s_fs_info; gfs2_quota_sync(sb, -1); - if (wait && sdp) + if (wait) gfs2_log_flush(sdp, NULL, NORMAL_FLUSH); - return 0; + return sdp->sd_log_error; } void gfs2_freeze_func(struct work_struct *work) -- 2.20.1