[PATCH V2 0/4] nvmet: allow target to export readonly ns

[Chaitanya Kulkarni]

Hi,

This patch series allows the target to export the read-only ns. The first
patch changes the type of the ns bool read-only attr to nvme_ns_wp_state
write-protect so that we can store the state.

The second patch adds the new ns write_protect configfs attr which user
can set to make ns read-only, we don't allow user to change the 
write-protect value when it is set from configfs.

The last two patches allow the user to open the ns in the read-only mode since
by default we open the ns in read-write mode which will fail if ns
backend is set to read-only.

Regards,
Chaitanya

* Changes from V1:-

1. Add a prep patch to store the ns write protect state.
2. Don't allow the host to change the ns-write-protect state when the state
   is set from configfs to the NVME_NS_WRITE_PROTECT_PERMANENT.
3. Change the ns bool type readonly to nvme_ns_wp_state type
   write_protect.
4. Update the id-ctrl field nwpc to inidicate support for write protection
   permanent state and don't set the bit 1 of the replay protection block
   Namesapce Write Protection Control so indicate any attempts of
   set-feature cmd with permanent write protection ns value will fail.

Chaitanya Kulkarni (4):
  nvmet: change the type of the ns->readonly
  nvmet: allow user to set the ns readonly
  nvmet: allow readonly bdev-ns to be configured
  nvmet: allow readonly file-ns to be configured

 drivers/nvme/target/admin-cmd.c   | 36 ++++++++++++++++++++-----------
 drivers/nvme/target/configfs.c    | 33 ++++++++++++++++++++++++++++
 drivers/nvme/target/core.c        |  3 ++-
 drivers/nvme/target/io-cmd-bdev.c |  4 ++--
 drivers/nvme/target/io-cmd-file.c |  2 +-
 drivers/nvme/target/nvmet.h       |  2 +-
 include/linux/nvme.h              |  2 +-
 7 files changed, 64 insertions(+), 18 deletions(-)

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2.22.1