Commit Graph

57 Commits

Author SHA1 Message Date
Linus Torvalds
0c00ed308d Merge tag 'for-7.0/block-20260206' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux
Pull block updates from Jens Axboe:

 - Support for batch request processing for ublk, improving the
   efficiency of the kernel/ublk server communication. This can yield
   nice 7-12% performance improvements

 - Support for integrity data for ublk

 - Various other ublk improvements and additions, including a ton of
   selftests additions and updated

 - Move the handling of blk-crypto software fallback from below the
   block layer to above it. This reduces the complexity of dealing with
   bio splitting

 - Series fixing a number of potential deadlocks in blk-mq related to
   the queue usage counter and writeback throttling and rq-qos debugfs
   handling

 - Add an async_depth queue attribute, to resolve a performance
   regression that's been around for a qhilw related to the scheduler
   depth handling

 - Only use task_work for IOPOLL completions on NVMe, if it is necessary
   to do so. An earlier fix for an issue resulted in all these
   completions being punted to task_work, to guarantee that completions
   were only run for a given io_uring ring when it was local to that
   ring. With the new changes, we can detect if it's necessary to use
   task_work or not, and avoid it if possible.

 - rnbd fixes:
      - Fix refcount underflow in device unmap path
      - Handle PREFLUSH and NOUNMAP flags properly in protocol
      - Fix server-side bi_size for special IOs
      - Zero response buffer before use
      - Fix trace format for flags
      - Add .release to rnbd_dev_ktype

 - MD pull requests via Yu Kuai
      - Fix raid5_run() to return error when log_init() fails
      - Fix IO hang with degraded array with llbitmap
      - Fix percpu_ref not resurrected on suspend timeout in llbitmap
      - Fix GPF in write_page caused by resize race
      - Fix NULL pointer dereference in process_metadata_update
      - Fix hang when stopping arrays with metadata through dm-raid
      - Fix any_working flag handling in raid10_sync_request
      - Refactor sync/recovery code path, improve error handling for
        badblocks, and remove unused recovery_disabled field
      - Consolidate mddev boolean fields into mddev_flags
      - Use mempool to allocate stripe_request_ctx and make sure
        max_sectors is not less than io_opt in raid5
      - Fix return value of mddev_trylock
      - Fix memory leak in raid1_run()
      - Add Li Nan as mdraid reviewer

 - Move phys_vec definitions to the kernel types, mostly in preparation
   for some VFIO and RDMA changes

 - Improve the speed for secure erase for some devices

 - Various little rust updates

 - Various other minor fixes, improvements, and cleanups

* tag 'for-7.0/block-20260206' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux: (162 commits)
  blk-mq: ABI/sysfs-block: fix docs build warnings
  selftests: ublk: organize test directories by test ID
  block: decouple secure erase size limit from discard size limit
  block: remove redundant kill_bdev() call in set_blocksize()
  blk-mq: add documentation for new queue attribute async_dpeth
  block, bfq: convert to use request_queue->async_depth
  mq-deadline: covert to use request_queue->async_depth
  kyber: covert to use request_queue->async_depth
  blk-mq: add a new queue sysfs attribute async_depth
  blk-mq: factor out a helper blk_mq_limit_depth()
  blk-mq-sched: unify elevators checking for async requests
  block: convert nr_requests to unsigned int
  block: don't use strcpy to copy blockdev name
  blk-mq-debugfs: warn about possible deadlock
  blk-mq-debugfs: add missing debugfs_mutex in blk_mq_debugfs_register_hctxs()
  blk-mq-debugfs: remove blk_mq_debugfs_unregister_rqos()
  blk-mq-debugfs: make blk_mq_debugfs_register_rqos() static
  blk-rq-qos: fix possible debugfs_mutex deadlock
  blk-mq-debugfs: factor out a helper to register debugfs for all rq_qos
  blk-wbt: fix possible deadlock to nest pcpu_alloc_mutex under q_usage_counter
  ...
2026-02-09 17:57:21 -08:00
Linus Torvalds
5c40222af1 Merge tag 'linux_kselftest-next-6.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest
Pull kselftest updates from Shuah Khan:
 "resctrl test:
   - fix division by zero error on Hygon
   - fix non-contiguous CBM check for Hygon
   - define CPU vendor IDs as bits to match usage
   - add CPU vendor detection for Hygon

  misc:
   - coredeump test: use __builtin_trap() instead of a null pointer
   - anon_inode: replace null pointers with empty arrays
   - kublk: include message in _Static_assert for C11 compatibility
   - run_kselftest.sh: add `--skip` argument option
   - pidfd: fix typo in comment"

* tag 'linux_kselftest-next-6.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest:
  selftests/pidfd: fix typo in comment
  selftests/run_kselftest.sh: Add `--skip` argument option
  selftests/resctrl: Fix non-contiguous CBM check for Hygon
  selftests/resctrl: Add CPU vendor detection for Hygon
  selftests/resctrl: Define CPU vendor IDs as bits to match usage
  selftests/resctrl: Fix a division by zero error on Hygon
  kselftest/kublk: include message in _Static_assert for C11 compatibility
  kselftest/anon_inode: replace null pointers with empty arrays
  kselftest/coredump: use __builtin_trap() instead of null pointer
2026-02-09 09:42:21 -08:00
Ming Lei
e07a2039b6 selftests: ublk: add selftest for UBLK_F_NO_AUTO_PART_SCAN
Add test_part_01.sh to test the UBLK_F_NO_AUTO_PART_SCAN feature
flag which allows suppressing automatic partition scanning during
device startup while still allowing manual partition probing.

The test verifies:
- Normal behavior: partitions are auto-detected without the flag
- With flag: partitions are not auto-detected during START_DEV
- Manual scan: blockdev --rereadpt works with the flag

Also update kublk tool to support --no_auto_part_scan option and
recognize the feature flag.

Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2026-01-31 06:36:41 -07:00
Ming Lei
e8cd481cc6 selftests: ublk: support arbitrary threads/queues combination
Enable flexible thread-to-queue mapping in batch I/O mode to support
arbitrary combinations of threads and queues, improving resource
utilization and scalability.

Key improvements:
- Support N:M thread-to-queue mapping (previously limited to 1:1)
- Dynamic buffer allocation based on actual queue assignment per thread
- Thread-safe queue preparation with spinlock protection
- Intelligent buffer index calculation for multi-queue scenarios
- Enhanced validation for thread/queue combination constraints

Implementation details:
- Add q_thread_map matrix to track queue-to-thread assignments
- Dynamic allocation of commit and fetch buffers per thread
- Round-robin queue assignment algorithm for load balancing
- Per-queue spinlock to prevent race conditions during prep
- Updated buffer index calculation using queue position within thread

This enables efficient configurations like:
- Any other N:M combinations for optimal resource matching

Testing:
- Added test_batch_02.sh: 4 threads vs 1 queue
- Added test_batch_03.sh: 1 thread vs 4 queues
- Validates correctness across different mapping scenarios

Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2026-01-22 20:05:41 -07:00
Ming Lei
cb5a6b3087 selftests: ublk: handle UBLK_U_IO_FETCH_IO_CMDS
Add support for UBLK_U_IO_FETCH_IO_CMDS to enable efficient batch
fetching of I/O commands using multishot io_uring operations.

Key improvements:
- Implement multishot UBLK_U_IO_FETCH_IO_CMDS for continuous command fetching
- Add fetch buffer management with page-aligned, mlocked buffers
- Process fetched I/O command tags from kernel-provided buffers
- Integrate fetch operations with existing batch I/O infrastructure
- Significantly reduce uring_cmd issuing overhead through batching

The implementation uses two fetch buffers per thread with automatic
requeuing to maintain continuous I/O command flow. Each fetch operation
retrieves multiple command tags in a single syscall, dramatically
improving performance compared to individual command fetching.

Technical details:
- Fetch buffers are page-aligned and mlocked for optimal performance
- Uses IORING_URING_CMD_MULTISHOT for continuous operation
- Automatic buffer management and requeuing on completion
- Enhanced CQE handling for fetch command completions

Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2026-01-22 20:05:41 -07:00
Ming Lei
dee7024ffe selftests: ublk: handle UBLK_U_IO_COMMIT_IO_CMDS
Implement UBLK_U_IO_COMMIT_IO_CMDS to enable efficient batched
completion of I/O operations in the batch I/O framework.

This completes the batch I/O infrastructure by adding the commit
phase that notifies the kernel about completed I/O operations:

Key features:
- Batch multiple I/O completions into single UBLK_U_IO_COMMIT_IO_CMDS
- Dynamic commit buffer allocation and management per thread
- Automatic commit buffer preparation before processing events
- Commit buffer submission after processing completed I/Os
- Integration with existing completion workflows

Implementation details:
- ublk_batch_prep_commit() allocates and initializes commit buffers
- ublk_batch_complete_io() adds completed I/Os to current batch
- ublk_batch_commit_io_cmds() submits batched completions to kernel
- Modified ublk_process_io() to handle batch commit lifecycle
- Enhanced ublk_complete_io() to route to batch or legacy completion

The commit buffer stores completion information (tag, result, buffer
details) for multiple I/Os, then submits them all at once, significantly
reducing syscall overhead compared to individual I/O completions.

Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2026-01-22 20:05:41 -07:00
Ming Lei
d468930a01 selftests: ublk: handle UBLK_U_IO_PREP_IO_CMDS
Implement support for UBLK_U_IO_PREP_IO_CMDS in the batch I/O framework:

- Add batch command initialization and setup functions
- Implement prep command queueing with proper buffer management
- Add command completion handling for prep and commit commands
- Integrate batch I/O setup into thread initialization
- Update CQE handling to support batch commands

The implementation uses the previously established buffer management
infrastructure to queue UBLK_U_IO_PREP_IO_CMDS commands. Commands are
prepared in the first thread context and use commit buffers for
efficient command batching.

Key changes:
- ublk_batch_queue_prep_io_cmds() prepares I/O command batches
- ublk_batch_compl_cmd() handles batch command completions
- Modified thread setup to use batch operations when enabled
- Enhanced buffer index calculation for batch mode

Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2026-01-22 20:05:41 -07:00
Ming Lei
dccbfa9d41 selftests: ublk: add batch buffer management infrastructure
Add the foundational infrastructure for UBLK_F_BATCH_IO buffer
management including:

- Allocator utility functions for small sized per-thread allocation
- Batch buffer allocation and deallocation functions
- Buffer index management for commit buffers
- Thread state management for batch I/O mode
- Buffer size calculation based on device features

This prepares the groundwork for handling batch I/O commands by
establishing the buffer management layer needed for UBLK_U_IO_PREP_IO_CMDS
and UBLK_U_IO_COMMIT_IO_CMDS operations.

The allocator uses CPU sets for efficient per-thread buffer tracking,
and commit buffers are pre-allocated with 2 buffers per thread to handle
overlapping command operations.

Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2026-01-22 20:05:41 -07:00
Ming Lei
f1d621b5a0 selftests: ublk: add ublk_io_buf_idx() for returning io buffer index
Since UBLK_F_PER_IO_DAEMON is added, io buffer index may depend on current
thread because the common way is to use per-pthread io_ring_ctx for issuing
ublk uring_cmd.

Add one helper for returning io buffer index, so we can hide the buffer
index implementation details for target code.

Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2026-01-22 20:05:41 -07:00
Ming Lei
584709ad5c selftests: ublk: replace assert() with ublk_assert()
Replace assert() with ublk_assert() since it is often triggered in daemon,
and we may get nothing shown in terminal.

Add ublk_assert(), so we can log something to syslog when assert() is
triggered.

Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2026-01-22 20:05:41 -07:00
Ming Lei
caf84294ff selftests: ublk: fix user_data truncation for tgt_data >= 256
The build_user_data() function packs multiple fields into a __u64
value using bit shifts. Without explicit __u64 casts before shifting,
the shift operations are performed on 32-bit unsigned integers before
being promoted to 64-bit, causing data loss.

Specifically, when tgt_data >= 256, the expression (tgt_data << 24)
shifts on a 32-bit value, truncating the upper 8 bits before promotion
to __u64. Since tgt_data can be up to 16 bits (assertion allows up to
65535), values >= 256 would have their high byte lost.

Add explicit __u64 casts to both op and tgt_data before shifting to
ensure the shift operations happen in 64-bit space, preserving all
bits of the input values.

user_data_to_tgt_data() is only used by stripe.c, in which the max
supported member disks are 4, so won't trigger this issue.

Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2026-01-22 20:05:41 -07:00
Ming Lei
65955a0993 selftests: ublk: add stop command with --safe option
Add 'stop' subcommand to kublk utility that uses the new
UBLK_CMD_TRY_STOP_DEV command when --safe option is specified.
This allows stopping a device only if it has no active openers,
returning -EBUSY otherwise.

Also add test_generic_16.sh to test the new functionality.

Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2026-01-12 15:07:31 -07:00
Caleb Sander Mateos
a180544267 selftests: ublk: support non-O_DIRECT backing files
A subsequent commit will add support for using a backing file to store
integrity data. Since integrity data is accessed in intervals of
metadata_size, which may be much smaller than a logical block on the
backing device, direct I/O cannot be used. Add an argument to
backing_file_tgt_init() to specify the number of files to open for
direct I/O. The remaining files will use buffered I/O. For now, continue
to request direct I/O for all the files.

Signed-off-by: Caleb Sander Mateos <csander@purestorage.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2026-01-12 09:16:38 -07:00
Caleb Sander Mateos
24f8a44b79 selftests: ublk: implement integrity user copy in kublk
If integrity data is enabled for kublk, allocate an integrity buffer for
each I/O. Extend ublk_user_copy() to copy the integrity data between the
ublk request and the integrity buffer if the ublksrv_io_desc indicates
that the request has integrity data.

Signed-off-by: Caleb Sander Mateos <csander@purestorage.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2026-01-12 09:16:38 -07:00
Caleb Sander Mateos
6ed6476c4a selftests: ublk: add kublk support for integrity params
Add integrity param command line arguments to kublk. Plumb these to
struct ublk_params for the null and fault_inject targets, as they don't
need to actually read or write the integrity data. Forbid the integrity
params for loop or stripe until the integrity data copy is implemented.

Signed-off-by: Caleb Sander Mateos <csander@purestorage.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2026-01-12 09:16:38 -07:00
Clint George
3e6ad272bb kselftest/kublk: include message in _Static_assert for C11 compatibility
Add descriptive message in the _Static_assert to comply with the C11
standard requirement to prevent compiler from throwing out error. The
compiler throws an error when _Static_assert is used without a message as
that is a C23 extension.

[] Testing:
The diff between before and after of running the kselftest test of the
module shows no regression on system with x86 architecture

[] Error log:
~/Desktop/kernel-dev/linux-v1/tools/testing/selftests/ublk$ make LLVM=1 W=1
  CC       kublk
In file included from kublk.c:6:
./kublk.h:220:43: error: '_Static_assert' with no message is a C23 extension [-Werror,-Wc23-extensions]
  220 |         _Static_assert(UBLK_MAX_QUEUES_SHIFT <= 7);
      |                                                  ^
      |                                                  , ""
1 error generated.
In file included from null.c:3:
./kublk.h:220:43: error: '_Static_assert' with no message is a C23 extension [-Werror,-Wc23-extensions]
  220 |         _Static_assert(UBLK_MAX_QUEUES_SHIFT <= 7);
      |                                                  ^
      |                                                  , ""
1 error generated.
In file included from file_backed.c:3:
./kublk.h:220:43: error: '_Static_assert' with no message is a C23 extension [-Werror,-Wc23-extensions]
  220 |         _Static_assert(UBLK_MAX_QUEUES_SHIFT <= 7);
      |                                                  ^
      |                                                  , ""
1 error generated.
In file included from common.c:3:
./kublk.h:220:43: error: '_Static_assert' with no message is a C23 extension [-Werror,-Wc23-extensions]
  220 |         _Static_assert(UBLK_MAX_QUEUES_SHIFT <= 7);
      |                                                  ^
      |                                                  , ""
1 error generated.
In file included from stripe.c:3:
./kublk.h:220:43: error: '_Static_assert' with no message is a C23 extension [-Werror,-Wc23-extensions]
  220 |         _Static_assert(UBLK_MAX_QUEUES_SHIFT <= 7);
      |                                                  ^
      |                                                  , ""
1 error generated.
In file included from fault_inject.c:11:
./kublk.h:220:43: error: '_Static_assert' with no message is a C23 extension [-Werror,-Wc23-extensions]
  220 |         _Static_assert(UBLK_MAX_QUEUES_SHIFT <= 7);
      |                                                  ^
      |                                                  , ""
1 error generated.
make: *** [../lib.mk:225: ~/Desktop/kernel-dev/linux-v1/tools/testing/selftests/ublk/kublk] Error 1

Link: https://lore.kernel.org/r/20251215085022.7642-1-clintbgeorge@gmail.com
Signed-off-by: Clint George <clintbgeorge@gmail.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2025-12-31 10:50:21 -07:00
Caleb Sander Mateos
b9f0a94c3b selftests: ublk: add support for user copy to kublk
The ublk selftests mock ublk server kublk supports every data copy mode
except user copy. Add support for user copy to kublk, enabled via the
--user_copy (-u) command line argument. On writes, issue pread() calls
to copy the write data into the ublk_io's buffer before dispatching the
write to the target implementation. On reads, issue pwrite() calls to
copy read data from the ublk_io's buffer before committing the request.
Copy in 2 KB chunks to provide some coverage of the offseting logic.

Signed-off-by: Caleb Sander Mateos <csander@purestorage.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-12-12 12:50:41 -07:00
Ming Lei
9637fc3bdd selftests: ublk: fix overflow in ublk_queue_auto_zc_fallback()
The functions ublk_queue_use_zc(), ublk_queue_use_auto_zc(), and
ublk_queue_auto_zc_fallback() were returning int, but performing
bitwise AND on q->flags which is __u64.

When a flag bit is set in the upper 32 bits (beyond INT_MAX), the
result of the bitwise AND operation could overflow when cast to int,
leading to incorrect boolean evaluation.

For example, if UBLKS_Q_AUTO_BUF_REG_FALLBACK is 0x8000000000000000:
  - (u64)flags & 0x8000000000000000 = 0x8000000000000000
  - Cast to int: undefined behavior / incorrect value
  - Used in if(): may evaluate incorrectly

Fix by:
1. Changing return type from int to bool for semantic correctness
2. Using !! to explicitly convert to boolean (0 or 1)

This ensures the functions return proper boolean values regardless
of which bit position the flags occupy in the 64-bit field.

Fixes: c3a6d48f86 ("selftests: ublk: remove ublk queue self-defined flags")
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-12-12 12:50:40 -07:00
Ming Lei
3f5b1169d2 selftests: ublk: make ublk_thread thread-local variable
Refactor ublk_thread to be a thread-local variable instead of storing
it in ublk_dev:

- Remove pthread_t thread field from struct ublk_thread and move it to
  struct ublk_thread_info

- Remove struct ublk_thread array from struct ublk_dev, reducing memory
  footprint

- Define struct ublk_thread as local variable in __ublk_io_handler_fn()
  instead of accessing it from dev->threads[]

- Extract main IO handling logic into __ublk_io_handler_fn() which is
  marked as noinline

- Move CPU affinity setup to ublk_io_handler_fn() before calling
  __ublk_io_handler_fn()

- Update ublk_thread_set_sched_affinity() to take struct ublk_thread_info *
  instead of struct ublk_thread *, and use pthread_setaffinity_np()
  instead of sched_setaffinity()

- Reorder struct ublk_thread fields to group related state together

This change makes each thread's ublk_thread structure truly local to
the thread, improving cache locality and reducing memory usage.

Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-11-03 08:34:59 -07:00
Ming Lei
9b2785ea85 ublk selftests: add --no_ublk_fixed_fd for not using registered ublk char device
Add a new command line option --no_ublk_fixed_fd that excludes the ublk
control device (/dev/ublkcN) from io_uring's registered files array.
When this option is used, only backing files are registered starting
from index 1, while the ublk control device is accessed using its raw
file descriptor.

Add ublk_get_registered_fd() helper function that returns the appropriate
file descriptor for use with io_uring operations.

Key optimizations implemented:
- Cache UBLKS_Q_NO_UBLK_FIXED_FD flag in ublk_queue.flags to avoid
  reading dev->no_ublk_fixed_fd in fast path
- Cache ublk char device fd in ublk_queue.ublk_fd for fast access
- Update ublk_get_registered_fd() to use ublk_queue * parameter
- Update io_uring_prep_buf_register/unregister() to use ublk_queue *
- Replace ublk_device * access with ublk_queue * access in fast paths

Also pass --no_ublk_fixed_fd to test_stress_04.sh for covering
plain ublk char device mode.

Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20250827121602.2619736-3-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-08-28 07:56:57 -06:00
Ming Lei
e56828f4df selftests: ublk: add utils.h
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20250713143415.2857561-18-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-07-15 08:04:17 -06:00
Ming Lei
a66f890176 selftests: ublk: improve flags naming
Improve all kinds of flags naming by adding its host structure suffix for
making code more readable.

Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20250713143415.2857561-16-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-07-15 08:04:17 -06:00
Ming Lei
c3a6d48f86 selftests: ublk: remove ublk queue self-defined flags
Remove ublk queue self-defined flags, and use the uapi flags directly.

Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20250713143415.2857561-15-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-07-15 08:04:17 -06:00
Ming Lei
92dda98424 selftests: ublk: pass 'ublk_thread *' to more common helpers
Pass 'ublk_thread *' to more common helpers, then we can avoid to store
this reference into 'struct ublk_io'.

Prepare for supporting to handle IO via different task context.

Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20250713143415.2857561-14-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-07-15 08:04:17 -06:00
Ming Lei
e0054835bf selftests: ublk: pass 'ublk_thread *' to ->queue_io() and ->tgt_io_done()
'struct thread' is task local structure, and the related code will become
more readable if we pass it via parameter.

Meantime pass 'ublk_thread *' to ublk_io_alloc_sqes(), and this way is
natural since we use per-thread io_uring for handling IO.

More importantly it helps much for removing the current ubq_daemon or
per-io-task limit.

Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20250713143415.2857561-13-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-07-15 08:04:17 -06:00
Ming Lei
b36c73251a selftests: ublk: remove tag parameter of ->tgt_io_done()
The `tag` parameter can be figured out from cqe->user_data, and that is
also the only way to get the info, so remove `tag` parameter, and
let target code retrieve it from cqe->user_data.

Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20250713143415.2857561-12-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-07-15 08:04:17 -06:00
Uday Shankar
abe54c1603 selftests: ublk: kublk: decouple ublk_queues from ublk server threads
Add support in kublk for decoupled ublk_queues and ublk server threads.
kublk now has two modes of operation:

- (preexisting mode) threads and queues are paired 1:1, and each thread
  services all the I/Os of one queue
- (new mode) thread and queue counts are independently configurable.
  threads service I/Os in a way that balances load across threads even
  if load is not balanced over queues.

The default is the preexisting mode. The new mode is activated by
passing the --per_io_tasks flag.

Signed-off-by: Uday Shankar <ushankar@purestorage.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20250529-ublk_task_per_io-v8-6-e9d3b119336a@purestorage.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-05-31 14:38:43 -06:00
Uday Shankar
b9848ca7a7 selftests: ublk: kublk: move per-thread data out of ublk_queue
Towards the goal of decoupling ublk_queues from ublk server threads,
move resources/data that should be per-thread rather than per-queue out
of ublk_queue and into a new struct ublk_thread.

Signed-off-by: Uday Shankar <ushankar@purestorage.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20250529-ublk_task_per_io-v8-5-e9d3b119336a@purestorage.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-05-31 14:38:39 -06:00
Uday Shankar
9773709752 selftests: ublk: kublk: tie sqe allocation to io instead of queue
We currently have a helper ublk_queue_alloc_sqes which the ublk targets
use to allocate SQEs for their own operations. However, as we move
towards decoupled ublk_queues and ublk server threads, this helper does
not make sense anymore. SQEs are allocated from rings, and we will have
one ring per thread to avoid locking. Change the SQE allocation helper
to ublk_io_alloc_sqes. Currently this still allocates SQEs from the io's
queue's ring, but when we fully decouple threads and queues, it will
allocate from the io's thread's ring instead.

Signed-off-by: Uday Shankar <ushankar@purestorage.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20250529-ublk_task_per_io-v8-3-e9d3b119336a@purestorage.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-05-31 14:38:30 -06:00
Uday Shankar
bf098d7269 selftests: ublk: kublk: plumb q_id in io_uring user_data
Currently, when we process CQEs, we know which ublk_queue we are working
on because we know which ring we are working on, and ublk_queues and
rings are in 1:1 correspondence. However, as we decouple ublk_queues
from ublk server threads, ublk_queues and rings will no longer be in 1:1
correspondence - each ublk server thread will have a ring, and each
thread may issue commands against more than one ublk_queue. So in order
to know which ublk_queue a CQE refers to, plumb that information in the
associated SQE's user_data.

Signed-off-by: Uday Shankar <ushankar@purestorage.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20250529-ublk_task_per_io-v8-2-e9d3b119336a@purestorage.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-05-31 14:38:26 -06:00
Ming Lei
f40b1f2670 selftests: ublk: add test case for UBLK_U_CMD_UPDATE_SIZE
Add test generic_10 for covering new control command of UBLK_U_CMD_UPDATE_SIZE.

Add 'update_size -s|--size size_in_bytes' sub-command on ublk utility for
supporting this feature, then verify the feature via generic_10.

Cc: Omri Mann <omri@nvidia.com>
Cc: Jared Holzman <jholzman@nvidia.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20250522163523.406289-2-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-05-23 09:42:12 -06:00
Ming Lei
6f1a182a87 selftests: ublk: add test for covering UBLK_AUTO_BUF_REG_FALLBACK
Add test for covering UBLK_AUTO_BUF_REG_FALLBACK:

- pass '--auto_zc_fallback' to null target, which requires both F_AUTO_BUF_REG
and F_SUPPORT_ZERO_COPY for handling UBLK_AUTO_BUF_REG_FALLBACK

- add ->buf_index() method for returning invalid buffer index to trigger
UBLK_AUTO_BUF_REG_FALLBACK

- add generic_09 for running the test

- add --auto_zc_fallback test in stress_03/stress_04/stress_05

Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20250520045455.515691-7-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-05-20 10:24:45 -06:00
Ming Lei
8ccebc19ee selftests: ublk: support UBLK_F_AUTO_BUF_REG
Enable UBLK_F_AUTO_BUF_REG support for ublk utility by argument `--auto_zc`,
meantime support this feature in null, loop and stripe target code.

Add function test generic_08 for covering basic UBLK_F_AUTO_BUF_REG feature.

Also cover UBLK_F_AUTO_BUF_REG in stress_03, stress_04 and stress_05 test too.

'fio/t/io_uring -p0 /dev/ublkb0' shows that F_AUTO_BUF_REG can improve
IOPS by 50% compared with F_SUPPORT_ZERO_COPY in my test VM.

Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20250520045455.515691-6-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-05-20 10:24:45 -06:00
Uday Shankar
e371b9d336 selftests: ublk: kublk: fix include path
Building kublk currently fails (with a "could not find linux/ublk_cmd.h"
error message) if kernel headers are not installed in a system-global
location (i.e. somewhere in the compiler's default include search path).
This failure is unnecessary, as make kselftest installs kernel headers
in the build tree - kublk's build just isn't looking for them properly.
There is an include path in kublk's CFLAGS which is probably intended to
find the kernel headers installed in the build tree; fix it so that it
can actually find them.

This introduces some macro redefinition issues between glibc-provided
headers and kernel headers; fix those by eliminating one include in
kublk.

Signed-off-by: Uday Shankar <ushankar@purestorage.com>
Reviewed-by: Caleb Sander Mateos <csander@purestorage.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20250429-ublk_selftests-v2-3-e970b6d9e4f4@purestorage.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-05-05 16:54:52 -06:00
Ming Lei
730d837979 selftests: ublk: fix UBLK_F_NEED_GET_DATA
Commit 57e13a2e8c ("selftests: ublk: support user recovery") starts to
support UBLK_F_NEED_GET_DATA for covering recovery feature, however the
ublk utility implementation isn't done correctly.

Fix it by supporting UBLK_F_NEED_GET_DATA correctly.

Also add test generic_07 for covering UBLK_F_NEED_GET_DATA.

Reviewed-by: Caleb Sander Mateos <csander@purestorage.com>
Fixes: 57e13a2e8c ("selftests: ublk: support user recovery")
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20250429022941.1718671-2-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-04-29 06:01:36 -06:00
Ming Lei
8f50363789 selftests: ublk: remove useless 'delay_us' from 'struct dev_ctx'
'delay_us' shouldn't be added to 'struct dev_ctx' since now it is
handled by per-target command line & 'struct fault_inject_ctx'.

So remove it.

Fixes: 81586652bb ("selftests: ublk: add generic_06 for covering fault inject")
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Uday Shankar <ushankar@purestorage.com>
Link: https://lore.kernel.org/r/20250421235947.715272-3-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-04-23 13:58:55 -06:00
Uday Shankar
81586652bb selftests: ublk: add generic_06 for covering fault inject
Add one simple fault inject target, and verify if an application using ublk
device sees an I/O error quickly after the ublk server dies.

Signed-off-by: Uday Shankar <ushankar@purestorage.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20250416035444.99569-9-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-04-16 19:33:21 -06:00
Ming Lei
57e13a2e8c selftests: ublk: support user recovery
Add user recovery feature.

Meantime add user recovery test: generic_04 and generic_05(zero copy)

Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20250412023035.2649275-12-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-04-16 19:32:18 -06:00
Ming Lei
810b88f3dc selftests: ublk: support target specific command line
Support target specific command line for making related command line code
handling more readable & clean.

Also helps for adding new features.

Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20250412023035.2649275-11-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-04-16 19:32:18 -06:00
Ming Lei
6c62fd04e8 selftests: ublk: increase max nr_queues and queue depth
Increase max nr_queues to 32, and queue depth to 1024.

Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20250412023035.2649275-10-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-04-16 19:32:18 -06:00
Ming Lei
2f0a692a93 selftests: ublk: set queue pthread's cpu affinity
In NUMA machine, ublk IO performance is very sensitive with queue
pthread's affinity setting.

Retrieve queue's affinity and select the 1st cpu as queue thread's sched
affinity, and it is observed that single cpu task affinity can get
stable & good performance if client application is put on proper cpu.

Dump this info when adding one ublk device. Use shmem to communicate
queue's tid between parent and daemon.

Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20250412023035.2649275-9-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-04-16 19:32:18 -06:00
Ming Lei
9cad26d66b selftests: ublk: add io_uring uapi header
Add io_uring UAPI header so that ublk can work with latest uapi
definition.

Fix the following build failure:

stripe.c: In function ‘stripe_to_uring_op’:
stripe.c:120:29: error: ‘IORING_OP_READV_FIXED’ undeclared (first use in this function); did you mean ‘IORING_OP_READ_FIXED’?
  120 |                 return zc ? IORING_OP_READV_FIXED : IORING_OP_READV;
      |                             ^~~~~~~~~~~~~~~~~~~~~
      |                             IORING_OP_READ_FIXED

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Fixes: 57ed58c132 ("selftests: ublk: enable zero copy for stripe target")
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20250412023035.2649275-3-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-04-16 19:32:18 -06:00
Ming Lei
ec12009318 selftests: ublk: fix ublk_find_tgt()
Bounds check for iterator variable `i` is missed, so add it and fix
ublk_find_tgt().

Cc: Johannes Thumshirn <Johannes.Thumshirn@wdc.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20250412023035.2649275-2-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-04-16 19:32:18 -06:00
Caleb Sander Mateos
25aaa81371 selftests: ublk: specify io_cmd_buf pointer type
Matching the ublk driver, change the type of io_cmd_buf from char * to
struct ublksrv_io_desc *.

Signed-off-by: Caleb Sander Mateos <csander@purestorage.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Acked-by: Shuah Khan <skhan@linuxfoundation.org>
Link: https://lore.kernel.org/r/20250328194230.2726862-3-csander@purestorage.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-03-29 05:56:36 -06:00
Ming Lei
0f3ebf2d4b selftests: ublk: add stripe target
Add ublk stripe target which can take 1~4 underlying backing files
or block device, with stripe size 4k ~ 512K.

Add two basic tests(write verify & mkfs/mount/umount) over ublk/stripe.

This target is helpful to cover multiple IOs aiming at same
fixed/registered IO kernel buffer.

It is also capable of verifying vectored registered (kernel)buffers
in future for zero copy, so far it isn't supported yet.

Todo: support vectored registered kernel buffer for ublk/zc.

Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20250322093218.431419-9-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-03-22 08:35:08 -06:00
Ming Lei
263846eb43 selftests: ublk: simplify loop io completion
Use the added target io handling helpers for simplifying loop io
completion.

Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20250322093218.431419-8-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-03-22 08:35:08 -06:00
Ming Lei
8cb9b971e2 selftests: ublk: enable zero copy for null target
Enable zero copy for null target so that we can evaluate performance
from zero copy or not.

Also this should be the simplest ublk zero copy implementation, which
can be served as zc example.

Add test for covering 'add -t null -z'.

Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20250322093218.431419-7-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-03-22 08:35:08 -06:00
Ming Lei
8842b72a82 selftests: ublk: prepare for supporting stripe target
- pass 'truct dev_ctx *ctx' to target init function

- add 'private_data' to 'struct ublk_dev' for storing target specific data

- add 'private_data' to 'struct ublk_io' for storing per-IO data

- add 'tgt_ios' to 'struct ublk_io' for counting how many io_uring ios
for handling the current io command

- add helper ublk_get_io() for supporting stripe target

- add two helpers for simplifying target io handling

Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20250322093218.431419-6-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-03-22 08:35:08 -06:00
Ming Lei
10d962dae2 selftests: ublk: move common code into common.c
Move two functions for initializing & de-initializing backing file
into common.c.

Also move one common helper into kublk.h.

Prepare for supporting ublk-stripe.

Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20250322093218.431419-5-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-03-22 08:35:08 -06:00
Ming Lei
9413c0ca8e selftests: ublk: increase max buffer size to 1MB
Increase max buffer size to 1MB, and 64KB is too small to evaluate
performance with builtin ublk server implementation.

Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20250322093218.431419-4-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-03-22 08:35:08 -06:00