1 files changed, 35 insertions, 12 deletions

diff --git a/drivers/md/raid5-cache.c b/drivers/md/raid5-cache.c
index 26ba09282e7c..4c00bc248287 100644
--- a/drivers/md/raid5-cache.c
+++ b/drivers/md/raid5-cache.c
@@ -24,6 +24,7 @@
 #include "md.h"
 #include "raid5.h"
 #include "bitmap.h"
+#include "raid5-log.h"
 
 /*
  * metadata/data stored in disk with 4k size unit (a block) regardless
@@ -622,20 +623,30 @@ static void r5l_do_submit_io(struct r5l_log *log, struct r5l_io_unit *io)
         __r5l_set_io_unit_state(io, IO_UNIT_IO_START);
         spin_unlock_irqrestore(&log->io_list_lock, flags);
 
+        /*
+         * In case of journal device failures, submit_bio will get error
+         * and calls endio, then active stripes will continue write
+         * process. Therefore, it is not necessary to check Faulty bit
+         * of journal device here.
+         *
+         * We can't check split_bio after current_bio is submitted. If
+         * io->split_bio is null, after current_bio is submitted, current_bio
+         * might already be completed and the io_unit is freed. We submit
+         * split_bio first to avoid the issue.
+         */
+        if (io->split_bio) {
+                if (io->has_flush)
+                        io->split_bio->bi_opf |= REQ_PREFLUSH;
+                if (io->has_fua)
+                        io->split_bio->bi_opf |= REQ_FUA;
+                submit_bio(io->split_bio);
+        }
+
         if (io->has_flush)
                 io->current_bio->bi_opf |= REQ_PREFLUSH;
         if (io->has_fua)
                 io->current_bio->bi_opf |= REQ_FUA;
         submit_bio(io->current_bio);
-
-        if (!io->split_bio)
-                return;
-
-        if (io->has_flush)
-                io->split_bio->bi_opf |= REQ_PREFLUSH;
-        if (io->has_fua)
-                io->split_bio->bi_opf |= REQ_FUA;
-        submit_bio(io->split_bio);
 }
 
 /* deferred io_unit will be dispatched here */
@@ -670,6 +681,11 @@ static void r5c_disable_writeback_async(struct work_struct *work)
                 return;
         pr_info("md/raid:%s: Disabling writeback cache for degraded array.\n",
                 mdname(mddev));
+
+        /* wait superblock change before suspend */
+        wait_event(mddev->sb_wait,
+                   !test_bit(MD_SB_CHANGE_PENDING, &mddev->sb_flags));
+
         mddev_suspend(mddev);
         log->r5c_journal_mode = R5C_JOURNAL_MODE_WRITE_THROUGH;
         mddev_resume(mddev);
@@ -2621,8 +2637,11 @@ int r5c_try_caching_write(struct r5conf *conf,
          * When run in degraded mode, array is set to write-through mode.
          * This check helps drain pending write safely in the transition to
          * write-through mode.
+         *
+         * When a stripe is syncing, the write is also handled in write
+         * through mode.
          */
-        if (s->failed) {
+        if (s->failed || test_bit(STRIPE_SYNCING, &sh->state)) {
                 r5c_make_stripe_write_out(sh);
                 return -EAGAIN;
         }
@@ -2825,6 +2844,9 @@ void r5c_finish_stripe_write_out(struct r5conf *conf,
         }
 
         r5l_append_flush_payload(log, sh->sector);
+        /* stripe is flused to raid disks, we can do resync now */
+        if (test_bit(STRIPE_SYNC_REQUESTED, &sh->state))
+                set_bit(STRIPE_HANDLE, &sh->state);
 }
 
 int r5c_cache_data(struct r5l_log *log, struct stripe_head *sh)
@@ -2973,7 +2995,7 @@ ioerr:
         return ret;
 }
 
-void r5c_update_on_rdev_error(struct mddev *mddev)
+void r5c_update_on_rdev_error(struct mddev *mddev, struct md_rdev *rdev)
 {
         struct r5conf *conf = mddev->private;
         struct r5l_log *log = conf->log;
@@ -2981,7 +3003,8 @@ void r5c_update_on_rdev_error(struct mddev *mddev)
         if (!log)
                 return;
 
-        if (raid5_calc_degraded(conf) > 0 &&
+        if ((raid5_calc_degraded(conf) > 0 ||
+             test_bit(Journal, &rdev->flags)) &&
             conf->log->r5c_journal_mode == R5C_JOURNAL_MODE_WRITE_BACK)
                 schedule_work(&log->disable_writeback_work);
 }