diff options
| -rw-r--r-- | drivers/md/dm-stripe.c | 82 |
1 files changed, 81 insertions, 1 deletions
diff --git a/drivers/md/dm-stripe.c b/drivers/md/dm-stripe.c index 969944a8aba2..7c5e2a0c3f2d 100644 --- a/drivers/md/dm-stripe.c +++ b/drivers/md/dm-stripe.c @@ -14,10 +14,13 @@ #include <linux/log2.h> #define DM_MSG_PREFIX "striped" +#define DM_IO_ERROR_THRESHOLD 15 struct stripe { struct dm_dev *dev; sector_t physical_start; + + atomic_t error_count; }; struct stripe_c { @@ -30,9 +33,29 @@ struct stripe_c { uint32_t chunk_shift; sector_t chunk_mask; + /* Needed for handling events */ + struct dm_target *ti; + + /* Work struct used for triggering events*/ + struct work_struct kstriped_ws; + struct stripe stripe[0]; }; +static struct workqueue_struct *kstriped; + +/* + * An event is triggered whenever a drive + * drops out of a stripe volume. + */ +static void trigger_event(struct work_struct *work) +{ + struct stripe_c *sc = container_of(work, struct stripe_c, kstriped_ws); + + dm_table_event(sc->ti->table); + +} + static inline struct stripe_c *alloc_context(unsigned int stripes) { size_t len; @@ -63,6 +86,7 @@ static int get_stripe(struct dm_target *ti, struct stripe_c *sc, return -ENXIO; sc->stripe[stripe].physical_start = start; + return 0; } @@ -135,6 +159,11 @@ static int stripe_ctr(struct dm_target *ti, unsigned int argc, char **argv) return -ENOMEM; } + INIT_WORK(&sc->kstriped_ws, trigger_event); + + /* Set pointer to dm target; used in trigger_event */ + sc->ti = ti; + sc->stripes = stripes; sc->stripe_width = width; ti->split_io = chunk_size; @@ -158,9 +187,11 @@ static int stripe_ctr(struct dm_target *ti, unsigned int argc, char **argv) kfree(sc); return r; } + atomic_set(&(sc->stripe[i].error_count), 0); } ti->private = sc; + return 0; } @@ -172,6 +203,7 @@ static void stripe_dtr(struct dm_target *ti) for (i = 0; i < sc->stripes; i++) dm_put_device(ti, sc->stripe[i].dev); + flush_workqueue(kstriped); kfree(sc); } @@ -213,13 +245,52 @@ static int stripe_status(struct dm_target *ti, return 0; } +static int stripe_end_io(struct dm_target *ti, struct bio *bio, + int error, union map_info *map_context) +{ + unsigned i; + char major_minor[16]; + struct stripe_c *sc = ti->private; + + if (!error) + return 0; /* I/O complete */ + + if ((error == -EWOULDBLOCK) && bio_rw_ahead(bio)) + return error; + + if (error == -EOPNOTSUPP) + return error; + + memset(major_minor, 0, sizeof(major_minor)); + sprintf(major_minor, "%d:%d", + bio->bi_bdev->bd_disk->major, + bio->bi_bdev->bd_disk->first_minor); + + /* + * Test to see which stripe drive triggered the event + * and increment error count for all stripes on that device. + * If the error count for a given device exceeds the threshold + * value we will no longer trigger any further events. + */ + for (i = 0; i < sc->stripes; i++) + if (!strcmp(sc->stripe[i].dev->name, major_minor)) { + atomic_inc(&(sc->stripe[i].error_count)); + if (atomic_read(&(sc->stripe[i].error_count)) < + DM_IO_ERROR_THRESHOLD) + queue_work(kstriped, &sc->kstriped_ws); + } + + return error; +} + static struct target_type stripe_target = { .name = "striped", - .version= {1, 0, 2}, + .version = {1, 1, 0}, .module = THIS_MODULE, .ctr = stripe_ctr, .dtr = stripe_dtr, .map = stripe_map, + .end_io = stripe_end_io, .status = stripe_status, }; @@ -231,6 +302,13 @@ int __init dm_stripe_init(void) if (r < 0) DMWARN("target registration failed"); + kstriped = create_singlethread_workqueue("kstriped"); + if (!kstriped) { + DMERR("failed to create workqueue kstriped"); + dm_unregister_target(&stripe_target); + return -ENOMEM; + } + return r; } @@ -239,5 +317,7 @@ void dm_stripe_exit(void) if (dm_unregister_target(&stripe_target)) DMWARN("target unregistration failed"); + destroy_workqueue(kstriped); + return; } |