bcache: re-work bbio IO error reporting

We can't call bch_notify_*() from atomic context, so move it to a new
ca->io_error_work.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>

6 files changed, 26 insertions, 15 deletions

diff --git a/drivers/md/bcache/bcache.h b/drivers/md/bcache/bcache.h
index 1250669cf37e..afc718930e02 100644
--- a/drivers/md/bcache/bcache.h
+++ b/drivers/md/bcache/bcache.h
@@ -327,6 +327,8 @@ struct cache {
 
 	struct journal_device	journal;
 
+	struct work_struct	io_error_work;
+
 	/* The rest of this all shows up in sysfs */
 #define IO_ERROR_SHIFT		20
 	atomic_t		io_errors;
diff --git a/drivers/md/bcache/io.c b/drivers/md/bcache/io.c
index 09441498bf6a..cbaa60c3e762 100644
--- a/drivers/md/bcache/io.c
+++ b/drivers/md/bcache/io.c
@@ -192,21 +192,27 @@ void bch_count_io_errors(struct cache *ca, int error, const char *m)
 
 	if (error) {
 		char buf[BDEVNAME_SIZE];
-		unsigned errors = atomic_add_return(1 << IO_ERROR_SHIFT,
-						    &ca->io_errors);
 
-		if (errors < ca->set->error_limit) {
-			bch_notify_cache_error(ca, false, m);
+		atomic_add(1 << IO_ERROR_SHIFT, &ca->io_errors);
+		queue_work(system_long_wq, &ca->io_error_work);
+		printk_ratelimited(KERN_ERR "%s: IO error on %s",
+		       bdevname(ca->disk_sb.bdev, buf), m);
+	}
+}
 
-			pr_err("%s: IO error on %s, recovering",
-			       bdevname(ca->disk_sb.bdev, buf), m);
-		} else {
-			bch_notify_cache_error(ca, true, m);
+void bch_cache_io_error_work(struct work_struct *work)
+{
+	struct cache *ca = container_of(work, struct cache, io_error_work);
+	unsigned errors = atomic_read(&ca->io_errors);
+	char buf[BDEVNAME_SIZE];
 
-			if (bch_cache_remove(ca, true))
-				pr_err("%s: too many IO errors on %s, removing",
-				       bdevname(ca->disk_sb.bdev, buf), m);
-		}
+	if (errors < ca->set->error_limit) {
+		bch_notify_cache_error(ca, false);
+	} else {
+		bch_notify_cache_error(ca, true);
+		printk_ratelimited(KERN_ERR "%s: too many IO errors, removing",
+		       bdevname(ca->disk_sb.bdev, buf));
+		bch_cache_remove(ca, true);
 	}
 }
 
diff --git a/drivers/md/bcache/io.h b/drivers/md/bcache/io.h
index 25c1ede300d3..f25513c172c8 100644
--- a/drivers/md/bcache/io.h
+++ b/drivers/md/bcache/io.h
@@ -76,6 +76,7 @@ void bch_write(struct closure *);
 
 int bch_read(struct cache_set *, struct bio *, u64);
 
+void bch_cache_io_error_work(struct work_struct *);
 void bch_count_io_errors(struct cache *, int, const char *);
 void bch_bbio_count_io_errors(struct bbio *, int, const char *);
 void bch_bbio_endio(struct bbio *, int, const char *);
diff --git a/drivers/md/bcache/notify.c b/drivers/md/bcache/notify.c
index 9d3a8ca78ae2..99a70f28d4e5 100644
--- a/drivers/md/bcache/notify.c
+++ b/drivers/md/bcache/notify.c
@@ -5,6 +5,7 @@
  */
 
 #include "bcache.h"
+#include "notify.h"
 
 #include <linux/kobject.h>
 
@@ -112,13 +113,12 @@ void bch_notify_cache_removed(struct cache *ca)
 	notify_put(c);
 }
 
-void bch_notify_cache_error(struct cache *ca, bool fatal, const char *m)
+void bch_notify_cache_error(struct cache *ca, bool fatal)
 {
 	struct cache_set *c = ca->set;
 
 	notify_get_cache(ca);
 	notify_var(c, "STATE=error");
 	notify_var(c, "FATAL=%d", fatal);
-	notify_var(c, "MESSAGE=%s", m);
 	notify_put(c);
 }
diff --git a/drivers/md/bcache/notify.h b/drivers/md/bcache/notify.h
index b915feff3c00..e121a711cf1d 100644
--- a/drivers/md/bcache/notify.h
+++ b/drivers/md/bcache/notify.h
@@ -16,6 +16,6 @@ void bch_notify_cache_read_only(struct cache *);
 void bch_notify_cache_added(struct cache *);
 void bch_notify_cache_removing(struct cache *);
 void bch_notify_cache_removed(struct cache *);
-void bch_notify_cache_error(struct cache *, bool, const char *);
+void bch_notify_cache_error(struct cache *, bool);
 
 #endif /* _NOTIFY_H */
diff --git a/drivers/md/bcache/super.c b/drivers/md/bcache/super.c
index 8a81c3e04b2f..3630088946fb 100644
--- a/drivers/md/bcache/super.c
+++ b/drivers/md/bcache/super.c
@@ -1766,6 +1766,8 @@ static const char *cache_alloc(struct bcache_superblock *sb,
 	ca->disk_sb.bdev->bd_holder = ca;
 	memset(sb, 0, sizeof(*sb));
 
+	INIT_WORK(&ca->io_error_work, bch_cache_io_error_work);
+
 	err = "dynamic fault";
 	if (cache_set_init_fault("cache_alloc"))
 		goto err;