Merge tag 'for-5.18/drivers-2022-03-18' of git://git.kernel.dk/linux-block

Pull block driver updates from Jens Axboe:

 - NVMe updates via Christoph:
      - add vectored-io support for user-passthrough (Kanchan Joshi)
      - add verbose error logging (Alan Adamson)
      - support buffered I/O on block devices in nvmet (Chaitanya
        Kulkarni)
      - central discovery controller support (Martin Belanger)
      - fix and extended the globally unique idenfier validation
        (Christoph)
      - move away from the deprecated IDA APIs (Sagi Grimberg)
      - misc code cleanup (Keith Busch, Max Gurtovoy, Qinghua Jin,
        Chaitanya Kulkarni)
      - add lockdep annotations for in-kernel sockets (Chris Leech)
      - use vmalloc for ANA log buffer (Hannes Reinecke)
      - kerneldoc fixes (Chaitanya Kulkarni)
      - cleanups (Guoqing Jiang, Chaitanya Kulkarni, Christoph)
      - warn about shared namespaces without multipathing (Christoph)

 - MD updates via Song with a set of cleanups (Christoph, Mariusz, Paul,
   Erik, Dirk)

 - loop cleanups and queue depth configuration (Chaitanya)

 - null_blk cleanups and fixes (Chaitanya)

 - Use descriptive init/exit names in virtio_blk (Randy)

 - Use bvec_kmap_local() in drivers (Christoph)

 - bcache fixes (Mingzhe)

 - xen blk-front persistent grant speedups (Juergen)

 - rnbd fix and cleanup (Gioh)

 - Misc fixes (Christophe, Colin)

* tag 'for-5.18/drivers-2022-03-18' of git://git.kernel.dk/linux-block: (76 commits)
  virtio_blk: eliminate anonymous module_init & module_exit
  nvme: warn about shared namespaces without CONFIG_NVME_MULTIPATH
  nvme: remove nvme_alloc_request and nvme_alloc_request_qid
  nvme: cleanup how disk->disk_name is assigned
  nvmet: move the call to nvmet_ns_changed out of nvmet_ns_revalidate
  nvmet: use snprintf() with PAGE_SIZE in configfs
  nvmet: don't fold lines
  nvmet-rdma: fix kernel-doc warning for nvmet_rdma_device_removal
  nvmet-fc: fix kernel-doc warning for nvmet_fc_unregister_targetport
  nvmet-fc: fix kernel-doc warning for nvmet_fc_register_targetport
  nvme-tcp: lockdep: annotate in-kernel sockets
  nvme-tcp: don't fold the line
  nvme-tcp: don't initialize ret variable
  nvme-multipath: call bio_io_error in nvme_ns_head_submit_bio
  nvme-multipath: use vmalloc for ANA log buffer
  xen/blkfront: speed up purge_persistent_grants()
  raid5: initialize the stripe_head embeeded bios as needed
  raid5-cache: statically allocate the recovery ra bio
  raid5-cache: fully initialize flush_bio when needed
  raid5-ppl: fully initialize the bio in ppl_new_iounit
  ...

1 files changed, 8 insertions, 0 deletions

diff --git a/drivers/nvme/target/io-cmd-bdev.c b/drivers/nvme/target/io-cmd-bdev.c
index 95c2bbb0b2f5..e9194804ddee 100644
--- a/drivers/nvme/target/io-cmd-bdev.c
+++ b/drivers/nvme/target/io-cmd-bdev.c
@@ -76,6 +76,14 @@ int nvmet_bdev_ns_enable(struct nvmet_ns *ns)
 {
 	int ret;
 
+	/*
+	 * When buffered_io namespace attribute is enabled that means user want
+	 * this block device to be used as a file, so block device can take
+	 * an advantage of cache.
+	 */
+	if (ns->buffered_io)
+		return -ENOTBLK;
+
 	ns->bdev = blkdev_get_by_path(ns->device_path,
 			FMODE_READ | FMODE_WRITE, NULL);
 	if (IS_ERR(ns->bdev)) {