diff options
Diffstat (limited to 'drivers/block/loop.c')
| -rw-r--r-- | drivers/block/loop.c | 34 |
1 files changed, 21 insertions, 13 deletions
diff --git a/drivers/block/loop.c b/drivers/block/loop.c index 102d79575895..44c9985f352a 100644 --- a/drivers/block/loop.c +++ b/drivers/block/loop.c @@ -264,20 +264,12 @@ lo_do_transfer(struct loop_device *lo, int cmd, return ret; } -static inline void loop_iov_iter_bvec(struct iov_iter *i, - unsigned int direction, const struct bio_vec *bvec, - unsigned long nr_segs, size_t count) -{ - iov_iter_bvec(i, direction, bvec, nr_segs, count); - i->type |= ITER_BVEC_FLAG_NO_REF; -} - static int lo_write_bvec(struct file *file, struct bio_vec *bvec, loff_t *ppos) { struct iov_iter i; ssize_t bw; - loop_iov_iter_bvec(&i, WRITE, bvec, 1, bvec->bv_len); + iov_iter_bvec(&i, WRITE, bvec, 1, bvec->bv_len); file_start_write(file); bw = vfs_iter_write(file, &i, ppos, 0); @@ -355,7 +347,7 @@ static int lo_read_simple(struct loop_device *lo, struct request *rq, ssize_t len; rq_for_each_segment(bvec, rq, iter) { - loop_iov_iter_bvec(&i, READ, &bvec, 1, bvec.bv_len); + iov_iter_bvec(&i, READ, &bvec, 1, bvec.bv_len); len = vfs_iter_read(lo->lo_backing_file, &i, &pos, 0); if (len < 0) return len; @@ -396,7 +388,7 @@ static int lo_read_transfer(struct loop_device *lo, struct request *rq, b.bv_offset = 0; b.bv_len = bvec.bv_len; - loop_iov_iter_bvec(&i, READ, &b, 1, b.bv_len); + iov_iter_bvec(&i, READ, &b, 1, b.bv_len); len = vfs_iter_read(lo->lo_backing_file, &i, &pos, 0); if (len < 0) { ret = len; @@ -563,7 +555,7 @@ static int lo_rw_aio(struct loop_device *lo, struct loop_cmd *cmd, } atomic_set(&cmd->ref, 2); - loop_iov_iter_bvec(&iter, rw, bvec, nr_bvec, 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; @@ -945,9 +937,20 @@ static int loop_set_fd(struct loop_device *lo, fmode_t mode, if (!file) goto out; + /* + * If we don't hold exclusive handle for the device, upgrade to it + * here to avoid changing device under exclusive owner. + */ + if (!(mode & FMODE_EXCL)) { + bdgrab(bdev); + error = blkdev_get(bdev, mode | FMODE_EXCL, loop_set_fd); + if (error) + goto out_putf; + } + error = mutex_lock_killable(&loop_ctl_mutex); if (error) - goto out_putf; + goto out_bdev; error = -EBUSY; if (lo->lo_state != Lo_unbound) @@ -1012,10 +1015,15 @@ static int loop_set_fd(struct loop_device *lo, fmode_t mode, mutex_unlock(&loop_ctl_mutex); if (partscan) loop_reread_partitions(lo, bdev); + if (!(mode & FMODE_EXCL)) + blkdev_put(bdev, mode | FMODE_EXCL); return 0; out_unlock: mutex_unlock(&loop_ctl_mutex); +out_bdev: + if (!(mode & FMODE_EXCL)) + blkdev_put(bdev, mode | FMODE_EXCL); out_putf: fput(file); out: |