Merge tag 'for-6.18/block-20250929' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux

Pull block updates from Jens Axboe:

 - NVMe pull request via Keith:
     - FC target fixes (Daniel)
     - Authentication fixes and updates (Martin, Chris)
     - Admin controller handling (Kamaljit)
     - Target lockdep assertions (Max)
     - Keep-alive updates for discovery (Alastair)
     - Suspend quirk (Georg)

 - MD pull request via Yu:
     - Add support for a lockless bitmap.

       A key feature for the new bitmap are that the IO fastpath is
       lockless. If a user issues lots of write IO to the same bitmap
       bit in a short time, only the first write has additional overhead
       to update bitmap bit, no additional overhead for the following
       writes.

       By supporting only resync or recover written data, means in the
       case creating new array or replacing with a new disk, there is no
       need to do a full disk resync/recovery.

 - Switch ->getgeo() and ->bios_param() to using struct gendisk rather
   than struct block_device.

 - Rust block changes via Andreas. This series adds configuration via
   configfs and remote completion to the rnull driver. The series also
   includes a set of changes to the rust block device driver API: a few
   cleanup patches, and a few features supporting the rnull changes.

   The series removes the raw buffer formatting logic from
   `kernel::block` and improves the logic available in `kernel::string`
   to support the same use as the removed logic.

 - floppy arch cleanups

 - Reduce the number of dereferencing needed for ublk commands

 - Restrict supported sockets for nbd. Mostly done to eliminate a class
   of issues perpetually reported by syzbot, by using nonsensical socket
   setups.

 - A few s390 dasd block fixes

 - Fix a few issues around atomic writes

 - Improve DMA interation for integrity requests

 - Improve how iovecs are treated with regards to O_DIRECT aligment
   constraints.

   We used to require each segment to adhere to the constraints, now
   only the request as a whole needs to.

 - Clean up and improve p2p support, enabling use of p2p for metadata
   payloads

 - Improve locking of request lookup, using SRCU where appropriate

 - Use page references properly for brd, avoiding very long RCU sections

 - Fix ordering of recursively submitted IOs

 - Clean up and improve updating nr_requests for a live device

 - Various fixes and cleanups

* tag 'for-6.18/block-20250929' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux: (164 commits)
  s390/dasd: enforce dma_alignment to ensure proper buffer validation
  s390/dasd: Return BLK_STS_INVAL for EINVAL from do_dasd_request
  ublk: remove redundant zone op check in ublk_setup_iod()
  nvme: Use non zero KATO for persistent discovery connections
  nvmet: add safety check for subsys lock
  nvme-core: use nvme_is_io_ctrl() for I/O controller check
  nvme-core: do ioccsz/iorcsz validation only for I/O controllers
  nvme-core: add method to check for an I/O controller
  blk-cgroup: fix possible deadlock while configuring policy
  blk-mq: fix null-ptr-deref in blk_mq_free_tags() from error path
  blk-mq: Fix more tag iteration function documentation
  selftests: ublk: fix behavior when fio is not installed
  ublk: don't access ublk_queue in ublk_unmap_io()
  ublk: pass ublk_io to __ublk_complete_rq()
  ublk: don't access ublk_queue in ublk_need_complete_req()
  ublk: don't access ublk_queue in ublk_check_commit_and_fetch()
  ublk: don't pass ublk_queue to ublk_fetch()
  ublk: don't access ublk_queue in ublk_config_io_buf()
  ublk: don't access ublk_queue in ublk_check_fetch_buf()
  ublk: pass q_id and tag to __ublk_check_and_get_req()
  ...

1 files changed, 61 insertions, 25 deletions

diff --git a/Documentation/admin-guide/md.rst b/Documentation/admin-guide/md.rst
index 4ff2cc291d18..1c2eacc94758 100644
--- a/Documentation/admin-guide/md.rst
+++ b/Documentation/admin-guide/md.rst
@@ -347,6 +347,54 @@ All md devices contain:
      active-idle
          like active, but no writes have been seen for a while (safe_mode_delay).
 
+  consistency_policy
+     This indicates how the array maintains consistency in case of unexpected
+     shutdown. It can be:
+
+     none
+       Array has no redundancy information, e.g. raid0, linear.
+
+     resync
+       Full resync is performed and all redundancy is regenerated when the
+       array is started after unclean shutdown.
+
+     bitmap
+       Resync assisted by a write-intent bitmap.
+
+     journal
+       For raid4/5/6, journal device is used to log transactions and replay
+       after unclean shutdown.
+
+     ppl
+       For raid5 only, Partial Parity Log is used to close the write hole and
+       eliminate resync.
+
+     The accepted values when writing to this file are ``ppl`` and ``resync``,
+     used to enable and disable PPL.
+
+  uuid
+     This indicates the UUID of the array in the following format:
+     xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx
+
+  bitmap_type
+     [RW] When read, this file will display the current and available
+     bitmap for this array. The currently active bitmap will be enclosed
+     in [] brackets. Writing an bitmap name or ID to this file will switch
+     control of this array to that new bitmap. Note that writing a new
+     bitmap for created array is forbidden.
+
+     none
+         No bitmap
+     bitmap
+         The default internal bitmap
+     llbitmap
+         The lockless internal bitmap
+
+If bitmap_type is not none, then additional bitmap attributes bitmap/xxx or
+llbitmap/xxx will be created after md device KOBJ_CHANGE event.
+
+If bitmap_type is bitmap, then the md device will also contain:
+
   bitmap/location
      This indicates where the write-intent bitmap for the array is
      stored.
@@ -401,35 +449,23 @@ All md devices contain:
      once the array becomes non-degraded, and this fact has been
      recorded in the metadata.
 
-  consistency_policy
-     This indicates how the array maintains consistency in case of unexpected
-     shutdown. It can be:
-
-     none
-       Array has no redundancy information, e.g. raid0, linear.
-
-     resync
-       Full resync is performed and all redundancy is regenerated when the
-       array is started after unclean shutdown.
-
-     bitmap
-       Resync assisted by a write-intent bitmap.
+If bitmap_type is llbitmap, then the md device will also contain:
 
-     journal
-       For raid4/5/6, journal device is used to log transactions and replay
-       after unclean shutdown.
+  llbitmap/bits
+     This is read-only, show status of bitmap bits, the number of each
+     value.
 
-     ppl
-       For raid5 only, Partial Parity Log is used to close the write hole and
-       eliminate resync.
-
-     The accepted values when writing to this file are ``ppl`` and ``resync``,
-     used to enable and disable PPL.
+  llbitmap/metadata
+     This is read-only, show bitmap metadata, include chunksize, chunkshift,
+     chunks, offset and daemon_sleep.
 
-  uuid
-     This indicates the UUID of the array in the following format:
-     xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx
+  llbitmap/daemon_sleep
+     This is read-write, time in seconds that daemon function will be
+     triggered to clear dirty bits.
 
+  llbitmap/barrier_idle
+     This is read-write, time in seconds that page barrier will be idled,
+     means dirty bits in the page will be cleared.
 
 As component devices are added to an md array, they appear in the ``md``
 directory as new directories named::