Merge tag 'md/4.15-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/shli/md

Pull md fixes from Shaohua Li:
 "Some MD fixes.

  The notable one is a raid5-cache deadlock bug with dm-raid, others are
  not significant"

* tag 'md/4.15-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/shli/md:
  md/raid1/10: add missed blk plug
  md: limit mdstat resync progress to max_sectors
  md/r5cache: move mddev_lock() out of r5c_journal_mode_set()
  md/raid5: correct degraded calculation in raid5_error

5 files changed, 21 insertions, 15 deletions

diff --git a/drivers/md/md.c b/drivers/md/md.c
index 41c050b59ec4..4e4dee0ec2de 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -7605,7 +7605,9 @@ static int status_resync(struct seq_file *seq, struct mddev *mddev)
                 if (test_bit(MD_RECOVERY_DONE, &mddev->recovery))
                         /* Still cleaning up */
                         resync = max_sectors;
-        } else
+        } else if (resync > max_sectors)
+                resync = max_sectors;
+        else
                 resync -= atomic_read(&mddev->recovery_active);
 
         if (resync == 0) {
diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c
index cc9d337a1ed3..6df398e3a008 100644
--- a/drivers/md/raid1.c
+++ b/drivers/md/raid1.c
@@ -809,11 +809,15 @@ static void flush_pending_writes(struct r1conf *conf)
         spin_lock_irq(&conf->device_lock);
 
         if (conf->pending_bio_list.head) {
+                struct blk_plug plug;
                 struct bio *bio;
+
                 bio = bio_list_get(&conf->pending_bio_list);
                 conf->pending_count = 0;
                 spin_unlock_irq(&conf->device_lock);
+                blk_start_plug(&plug);
                 flush_bio_list(conf, bio);
+                blk_finish_plug(&plug);
         } else
                 spin_unlock_irq(&conf->device_lock);
 }
diff --git a/drivers/md/raid10.c b/drivers/md/raid10.c
index b9edbc747a95..c131835cf008 100644
--- a/drivers/md/raid10.c
+++ b/drivers/md/raid10.c
@@ -894,10 +894,13 @@ static void flush_pending_writes(struct r10conf *conf)
         spin_lock_irq(&conf->device_lock);
 
         if (conf->pending_bio_list.head) {
+                struct blk_plug plug;
                 struct bio *bio;
+
                 bio = bio_list_get(&conf->pending_bio_list);
                 conf->pending_count = 0;
                 spin_unlock_irq(&conf->device_lock);
+                blk_start_plug(&plug);
                 /* flush any pending bitmap writes to disk
                  * before proceeding w/ I/O */
                 bitmap_unplug(conf->mddev->bitmap);
@@ -918,6 +921,7 @@ static void flush_pending_writes(struct r10conf *conf)
                                 generic_make_request(bio);
                         bio = next;
                 }
+                blk_finish_plug(&plug);
         } else
                 spin_unlock_irq(&conf->device_lock);
 }
diff --git a/drivers/md/raid5-cache.c b/drivers/md/raid5-cache.c
index f1c86d938502..39f31f07ffe9 100644
--- a/drivers/md/raid5-cache.c
+++ b/drivers/md/raid5-cache.c
@@ -2577,31 +2577,22 @@ static ssize_t r5c_journal_mode_show(struct mddev *mddev, char *page)
 int r5c_journal_mode_set(struct mddev *mddev, int mode)
 {
         struct r5conf *conf;
-        int err;
 
         if (mode < R5C_JOURNAL_MODE_WRITE_THROUGH ||
             mode > R5C_JOURNAL_MODE_WRITE_BACK)
                 return -EINVAL;
 
-        err = mddev_lock(mddev);
-        if (err)
-                return err;
         conf = mddev->private;
-        if (!conf || !conf->log) {
-                mddev_unlock(mddev);
+        if (!conf || !conf->log)
                 return -ENODEV;
-        }
 
         if (raid5_calc_degraded(conf) > 0 &&
-            mode == R5C_JOURNAL_MODE_WRITE_BACK) {
-                mddev_unlock(mddev);
+            mode == R5C_JOURNAL_MODE_WRITE_BACK)
                 return -EINVAL;
-        }
 
         mddev_suspend(mddev);
         conf->log->r5c_journal_mode = mode;
         mddev_resume(mddev);
-        mddev_unlock(mddev);
 
         pr_debug("md/raid:%s: setting r5c cache mode to %d: %s\n",
                  mdname(mddev), mode, r5c_journal_mode_str[mode]);
@@ -2614,6 +2605,7 @@ static ssize_t r5c_journal_mode_store(struct mddev *mddev,
 {
         int mode = ARRAY_SIZE(r5c_journal_mode_str);
         size_t len = length;
+        int ret;
 
         if (len < 2)
                 return -EINVAL;
@@ -2625,8 +2617,12 @@ static ssize_t r5c_journal_mode_store(struct mddev *mddev,
                 if (strlen(r5c_journal_mode_str[mode]) == len &&
                     !strncmp(page, r5c_journal_mode_str[mode], len))
                         break;
-
-        return r5c_journal_mode_set(mddev, mode) ?: length;
+        ret = mddev_lock(mddev);
+        if (ret)
+                return ret;
+        ret = r5c_journal_mode_set(mddev, mode);
+        mddev_unlock(mddev);
+        return ret ?: length;
 }
 
 struct md_sysfs_entry
diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c
index 31dc25e2871a..98ce4272ace9 100644
--- a/drivers/md/raid5.c
+++ b/drivers/md/raid5.c
@@ -2677,13 +2677,13 @@ static void raid5_error(struct mddev *mddev, struct md_rdev *rdev)
         pr_debug("raid456: error called\n");
 
         spin_lock_irqsave(&conf->device_lock, flags);
+        set_bit(Faulty, &rdev->flags);
         clear_bit(In_sync, &rdev->flags);
         mddev->degraded = raid5_calc_degraded(conf);
         spin_unlock_irqrestore(&conf->device_lock, flags);
         set_bit(MD_RECOVERY_INTR, &mddev->recovery);
 
         set_bit(Blocked, &rdev->flags);
-        set_bit(Faulty, &rdev->flags);
         set_mask_bits(&mddev->sb_flags, 0,
                       BIT(MD_SB_CHANGE_DEVS) | BIT(MD_SB_CHANGE_PENDING));
         pr_crit("md/raid:%s: Disk failure on %s, disabling device.\n"