Merge tag 'block-5.13-2021-05-07' of git://git.kernel.dk/linux-block

Pull block fixes from Jens Axboe:

 - dasd spelling fixes (Bhaskar)

 - Limit bio max size on multi-page bvecs to the hardware limit, to
   avoid overly large bio's (and hence latencies). Originally queued for
   the merge window, but needed a fix and was dropped from the initial
   pull (Changheun)

 - NVMe pull request (Christoph):
      - reset the bdev to ns head when failover (Daniel Wagner)
      - remove unsupported command noise (Keith Busch)
      - misc passthrough improvements (Kanchan Joshi)
      - fix controller ioctl through ns_head (Minwoo Im)
      - fix controller timeouts during reset (Tao Chiu)

 - rnbd fixes/cleanups (Gioh, Md, Dima)

 - Fix iov_iter re-expansion (yangerkun)

* tag 'block-5.13-2021-05-07' of git://git.kernel.dk/linux-block:
  block: reexpand iov_iter after read/write
  nvmet: remove unsupported command noise
  nvme-multipath: reset bdev to ns head when failover
  nvme-pci: fix controller reset hang when racing with nvme_timeout
  nvme: move the fabrics queue ready check routines to core
  nvme: avoid memset for passthrough requests
  nvme: add nvme_get_ns helper
  nvme: fix controller ioctl through ns_head
  bio: limit bio max size
  RDMA/rtrs: fix uninitialized symbol 'cnt'
  s390: dasd: Mundane spelling fixes
  block/rnbd: Remove all likely and unlikely
  block/rnbd-clt: Check the return value of the function rtrs_clt_query
  block/rnbd: Fix style issues
  block/rnbd-clt: Change queue_depth type in rnbd_clt_session to size_t

1 files changed, 17 insertions, 3 deletions

diff --git a/fs/block_dev.c b/fs/block_dev.c
index 9114e0a0e7b4..b8abccd03e5d 100644
--- a/fs/block_dev.c
+++ b/fs/block_dev.c
@@ -1677,6 +1677,7 @@ ssize_t blkdev_write_iter(struct kiocb *iocb, struct iov_iter *from)
 	struct inode *bd_inode = bdev_file_inode(file);
 	loff_t size = i_size_read(bd_inode);
 	struct blk_plug plug;
+	size_t shorted = 0;
 	ssize_t ret;
 
 	if (bdev_read_only(I_BDEV(bd_inode)))
@@ -1694,12 +1695,17 @@ ssize_t blkdev_write_iter(struct kiocb *iocb, struct iov_iter *from)
 	if ((iocb->ki_flags & (IOCB_NOWAIT | IOCB_DIRECT)) == IOCB_NOWAIT)
 		return -EOPNOTSUPP;
 
-	iov_iter_truncate(from, size - iocb->ki_pos);
+	size -= iocb->ki_pos;
+	if (iov_iter_count(from) > size) {
+		shorted = iov_iter_count(from) - size;
+		iov_iter_truncate(from, size);
+	}
 
 	blk_start_plug(&plug);
 	ret = __generic_file_write_iter(iocb, from);
 	if (ret > 0)
 		ret = generic_write_sync(iocb, ret);
+	iov_iter_reexpand(from, iov_iter_count(from) + shorted);
 	blk_finish_plug(&plug);
 	return ret;
 }
@@ -1711,13 +1717,21 @@ ssize_t blkdev_read_iter(struct kiocb *iocb, struct iov_iter *to)
 	struct inode *bd_inode = bdev_file_inode(file);
 	loff_t size = i_size_read(bd_inode);
 	loff_t pos = iocb->ki_pos;
+	size_t shorted = 0;
+	ssize_t ret;
 
 	if (pos >= size)
 		return 0;
 
 	size -= pos;
-	iov_iter_truncate(to, size);
-	return generic_file_read_iter(iocb, to);
+	if (iov_iter_count(to) > size) {
+		shorted = iov_iter_count(to) - size;
+		iov_iter_truncate(to, size);
+	}
+
+	ret = generic_file_read_iter(iocb, to);
+	iov_iter_reexpand(to, iov_iter_count(to) + shorted);
+	return ret;
 }
 EXPORT_SYMBOL_GPL(blkdev_read_iter);