diff options
Diffstat (limited to 'drivers/block/drbd')
| -rw-r--r-- | drivers/block/drbd/drbd_receiver.c | 45 | ||||
| -rw-r--r-- | drivers/block/drbd/drbd_worker.c | 7 |
2 files changed, 34 insertions, 18 deletions
diff --git a/drivers/block/drbd/drbd_receiver.c b/drivers/block/drbd/drbd_receiver.c index a56b107e01e..9e9fc341313 100644 --- a/drivers/block/drbd/drbd_receiver.c +++ b/drivers/block/drbd/drbd_receiver.c @@ -1073,6 +1073,16 @@ void drbd_bump_write_ordering(struct drbd_conf *mdev, enum write_ordering_e wo) * @mdev: DRBD device. * @e: epoch entry * @rw: flag field, see bio->bi_rw + * + * May spread the pages to multiple bios, + * depending on bio_add_page restrictions. + * + * Returns 0 if all bios have been submitted, + * -ENOMEM if we could not allocate enough bios, + * -ENOSPC (any better suggestion?) if we have not been able to bio_add_page a + * single page to an empty bio (which should never happen and likely indicates + * that the lower level IO stack is in some way broken). This has been observed + * on certain Xen deployments. */ /* TODO allocate from our own bio_set. */ int drbd_submit_ee(struct drbd_conf *mdev, struct drbd_epoch_entry *e, @@ -1085,6 +1095,7 @@ int drbd_submit_ee(struct drbd_conf *mdev, struct drbd_epoch_entry *e, unsigned ds = e->size; unsigned n_bios = 0; unsigned nr_pages = (ds + PAGE_SIZE -1) >> PAGE_SHIFT; + int err = -ENOMEM; /* In most cases, we will only need one bio. But in case the lower * level restrictions happen to be different at this offset on this @@ -1110,8 +1121,17 @@ next_bio: page_chain_for_each(page) { unsigned len = min_t(unsigned, ds, PAGE_SIZE); if (!bio_add_page(bio, page, len, 0)) { - /* a single page must always be possible! */ - BUG_ON(bio->bi_vcnt == 0); + /* A single page must always be possible! + * But in case it fails anyways, + * we deal with it, and complain (below). */ + if (bio->bi_vcnt == 0) { + dev_err(DEV, + "bio_add_page failed for len=%u, " + "bi_vcnt=0 (bi_sector=%llu)\n", + len, (unsigned long long)bio->bi_sector); + err = -ENOSPC; + goto fail; + } goto next_bio; } ds -= len; @@ -1137,7 +1157,7 @@ fail: bios = bios->bi_next; bio_put(bio); } - return -ENOMEM; + return err; } static int receive_Barrier(struct drbd_conf *mdev, enum drbd_packets cmd, unsigned int data_size) @@ -1436,9 +1456,8 @@ static int recv_resync_read(struct drbd_conf *mdev, sector_t sector, int data_si if (drbd_submit_ee(mdev, e, WRITE, DRBD_FAULT_RS_WR) == 0) return true; - /* drbd_submit_ee currently fails for one reason only: - * not being able to allocate enough bios. - * Is dropping the connection going to help? */ + /* don't care for the reason here */ + dev_err(DEV, "submit failed, triggering re-connect\n"); spin_lock_irq(&mdev->req_lock); list_del(&e->w.list); spin_unlock_irq(&mdev->req_lock); @@ -1837,9 +1856,8 @@ static int receive_Data(struct drbd_conf *mdev, enum drbd_packets cmd, unsigned if (drbd_submit_ee(mdev, e, rw, DRBD_FAULT_DT_WR) == 0) return true; - /* drbd_submit_ee currently fails for one reason only: - * not being able to allocate enough bios. - * Is dropping the connection going to help? */ + /* don't care for the reason here */ + dev_err(DEV, "submit failed, triggering re-connect\n"); spin_lock_irq(&mdev->req_lock); list_del(&e->w.list); hlist_del_init(&e->colision); @@ -1848,9 +1866,7 @@ static int receive_Data(struct drbd_conf *mdev, enum drbd_packets cmd, unsigned drbd_al_complete_io(mdev, e->sector); out_interrupted: - /* yes, the epoch_size now is imbalanced. - * but we drop the connection anyways, so we don't have a chance to - * receive a barrier... atomic_inc(&mdev->epoch_size); */ + drbd_may_finish_epoch(mdev, e->epoch, EV_PUT + EV_CLEANUP); put_ldev(mdev); drbd_free_ee(mdev, e); return false; @@ -2096,9 +2112,8 @@ submit: if (drbd_submit_ee(mdev, e, READ, fault_type) == 0) return true; - /* drbd_submit_ee currently fails for one reason only: - * not being able to allocate enough bios. - * Is dropping the connection going to help? */ + /* don't care for the reason here */ + dev_err(DEV, "submit failed, triggering re-connect\n"); spin_lock_irq(&mdev->req_lock); list_del(&e->w.list); spin_unlock_irq(&mdev->req_lock); diff --git a/drivers/block/drbd/drbd_worker.c b/drivers/block/drbd/drbd_worker.c index ff0eb308ee4..cfd324b9f95 100644 --- a/drivers/block/drbd/drbd_worker.c +++ b/drivers/block/drbd/drbd_worker.c @@ -369,9 +369,10 @@ static int read_for_csum(struct drbd_conf *mdev, sector_t sector, int size) if (drbd_submit_ee(mdev, e, READ, DRBD_FAULT_RS_RD) == 0) return 0; - /* drbd_submit_ee currently fails for one reason only: - * not being able to allocate enough bios. - * Is dropping the connection going to help? */ + /* If it failed because of ENOMEM, retry should help. If it failed + * because bio_add_page failed (probably broken lower level driver), + * retry may or may not help. + * If it does not, you may need to force disconnect. */ spin_lock_irq(&mdev->req_lock); list_del(&e->w.list); spin_unlock_irq(&mdev->req_lock); |