diff options
Diffstat (limited to 'drivers/block/loop.c')
| -rw-r--r-- | drivers/block/loop.c | 48 |
1 files changed, 31 insertions, 17 deletions
diff --git a/drivers/block/loop.c b/drivers/block/loop.c index cf5538942834..1e6edd568214 100644 --- a/drivers/block/loop.c +++ b/drivers/block/loop.c @@ -511,21 +511,22 @@ static int lo_rw_aio(struct loop_device *lo, struct loop_cmd *cmd, loff_t pos, bool rw) { struct iov_iter iter; + struct req_iterator rq_iter; struct bio_vec *bvec; struct request *rq = blk_mq_rq_from_pdu(cmd); struct bio *bio = rq->bio; struct file *file = lo->lo_backing_file; + struct bio_vec tmp; unsigned int offset; - int segments = 0; + int nr_bvec = 0; int ret; + rq_for_each_bvec(tmp, rq, rq_iter) + nr_bvec++; + if (rq->bio != rq->biotail) { - struct req_iterator iter; - struct bio_vec tmp; - __rq_for_each_bio(bio, rq) - segments += bio_segments(bio); - bvec = kmalloc_array(segments, sizeof(struct bio_vec), + bvec = kmalloc_array(nr_bvec, sizeof(struct bio_vec), GFP_NOIO); if (!bvec) return -EIO; @@ -534,10 +535,10 @@ static int lo_rw_aio(struct loop_device *lo, struct loop_cmd *cmd, /* * The bios of the request may be started from the middle of * the 'bvec' because of bio splitting, so we can't directly - * copy bio->bi_iov_vec to new bvec. The rq_for_each_segment + * copy bio->bi_iov_vec to new bvec. The rq_for_each_bvec * API will take care of all details for us. */ - rq_for_each_segment(tmp, rq, iter) { + rq_for_each_bvec(tmp, rq, rq_iter) { *bvec = tmp; bvec++; } @@ -551,11 +552,10 @@ static int lo_rw_aio(struct loop_device *lo, struct loop_cmd *cmd, */ offset = bio->bi_iter.bi_bvec_done; bvec = __bvec_iter_bvec(bio->bi_io_vec, bio->bi_iter); - segments = bio_segments(bio); } atomic_set(&cmd->ref, 2); - iov_iter_bvec(&iter, rw, bvec, segments, blk_rq_bytes(rq)); + iov_iter_bvec(&iter, rw, bvec, nr_bvec, blk_rq_bytes(rq)); iter.iov_offset = offset; cmd->iocb.ki_pos = pos; @@ -1089,16 +1089,12 @@ static int __loop_clr_fd(struct loop_device *lo, bool release) kobject_uevent(&disk_to_dev(bdev->bd_disk)->kobj, KOBJ_CHANGE); } mapping_set_gfp_mask(filp->f_mapping, gfp); - lo->lo_state = Lo_unbound; /* This is safe: open() is still holding a reference. */ module_put(THIS_MODULE); blk_mq_unfreeze_queue(lo->lo_queue); partscan = lo->lo_flags & LO_FLAGS_PARTSCAN && bdev; lo_number = lo->lo_number; - lo->lo_flags = 0; - if (!part_shift) - lo->lo_disk->flags |= GENHD_FL_NO_PART_SCAN; loop_unprepare_queue(lo); out_unlock: mutex_unlock(&loop_ctl_mutex); @@ -1115,11 +1111,29 @@ out_unlock: err = __blkdev_reread_part(bdev); else err = blkdev_reread_part(bdev); - pr_warn("%s: partition scan of loop%d failed (rc=%d)\n", - __func__, lo_number, err); + if (err) + pr_warn("%s: partition scan of loop%d failed (rc=%d)\n", + __func__, lo_number, err); /* Device is gone, no point in returning error */ err = 0; } + + /* + * lo->lo_state is set to Lo_unbound here after above partscan has + * finished. + * + * There cannot be anybody else entering __loop_clr_fd() as + * lo->lo_backing_file is already cleared and Lo_rundown state + * protects us from all the other places trying to change the 'lo' + * device. + */ + mutex_lock(&loop_ctl_mutex); + lo->lo_flags = 0; + if (!part_shift) + lo->lo_disk->flags |= GENHD_FL_NO_PART_SCAN; + lo->lo_state = Lo_unbound; + mutex_unlock(&loop_ctl_mutex); + /* * Need not hold loop_ctl_mutex to fput backing file. * Calling fput holding loop_ctl_mutex triggers a circular @@ -1937,7 +1951,7 @@ static int loop_add(struct loop_device **l, int i) lo->tag_set.queue_depth = 128; lo->tag_set.numa_node = NUMA_NO_NODE; lo->tag_set.cmd_size = sizeof(struct loop_cmd); - lo->tag_set.flags = BLK_MQ_F_SHOULD_MERGE | BLK_MQ_F_SG_MERGE; + lo->tag_set.flags = BLK_MQ_F_SHOULD_MERGE; lo->tag_set.driver_data = lo; err = blk_mq_alloc_tag_set(&lo->tag_set); |