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path: root/drivers/block/null_blk
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13 daysnull_blk: fix UBSAN shift-out-of-bounds when zone_size is 0 or overflowsRik van Riel
null_zone_no() does sect >> ilog2(dev->zone_size_sects). When zone_size_sects is 0, ilog2(0) returns -1, producing shift exponent -1 which UBSAN reports as shift-out-of-bounds. UBSAN: shift-out-of-bounds in drivers/block/null_blk/zoned.c:21:14 shift exponent -1 is negative Call Trace: null_zone_no drivers/block/null_blk/zoned.c:21 [inline] null_process_zoned_cmd+0xf76/0xf80 drivers/block/null_blk/zoned.c:728 null_handle_cmd drivers/block/null_blk/main.c:1455 [inline] null_queue_rq+0x8bc/0xe70 drivers/block/null_blk/main.c:1703 __blk_mq_issue_directly block/blk-mq.c:2694 [inline] blk_mq_try_issue_directly+0x3f4/0x880 block/blk-mq.c:2754 blk_mq_submit_bio+0x20c0/0x2a40 block/blk-mq.c:3208 submit_bio_noacct_nocheck+0x2f4/0xa40 block/blk-core.c:790 block_read_full_folio+0x7a6/0x810 fs/buffer.c:2463 filemap_read_folio+0x12c/0x3a0 mm/filemap.c:2510 read_part_sector+0xb6/0x2b0 block/partitions/core.c:724 adfspart_check_ICS+0xb1/0x960 block/partitions/acorn.c:357 check_partition block/partitions/core.c:143 [inline] blk_add_partitions block/partitions/core.c:591 [inline] bdev_disk_changed+0x851/0x17a0 block/partitions/core.c:695 blkdev_get_whole+0x372/0x510 block/bdev.c:751 add_disk_final block/genhd.c:412 [inline] add_disk_fwnode+0x24b/0x3a0 block/genhd.c:606 null_add_dev+0x130b/0x1d70 drivers/block/null_blk/main.c:2052 nullb_device_power_store+0x240/0x380 drivers/block/null_blk/main.c:501 configfs_write_iter+0x337/0x430 fs/configfs/file.c:229 Syzkaller triggers this by creating a zoned null_blk device via configfs. The Call Trace shows configfs_write_iter in configfs/file.c handling a write to power file, which calls nullb_device_power_store in main.c, which calls null_add_dev in main.c, which calls add_disk in genhd.c, which triggers partition scan via bdev_disk_changed in partitions/core.c. A zoned null_blk device with zone_size 0 should not be legal. Existing code tries to reject it via is_power_of_2() check in zoned.c and !zone_size check in main.c, but syzkaller can still reach null_zone_no() with zone_size_sects 0 via two paths: 1. Direct 0 via configfs: zone_size attribute store in main.c has NULLB_DEVICE_ATTR(zone_size, ulong, NULL) with no validation callback, so echo 0 > zone_size succeeds before power store. If zoned is false at power store time, the !zone_size check in main.c is skipped, and later zoned set true leaves zone_size 0. 2. Large value overflow: mb_to_sects() in zoned.c does (sector_t)mb * SZ_1M >> SECTOR_SHIFT which is mb * 2048. If mb is 1UL << 53 (9PB), mb * 2048 overflows 64-bit to 0. The value is power-of-two so is_power_of_2() passes, but mb_to_sects() returns 0. Check for zero zone_size explicitly in null_init_zoned_dev() in zoned.c, returning -EINVAL with "must be non-zero power-of-two". Check for zero zone_size_sects after mb_to_sects() conversion, returning -EINVAL for overflow case. Keep defensive check in null_zone_no() returning 0 for zero sectors to avoid shift out-of-bounds even if zero slips through. This change should be safe because zone_size is set once in null_init_zoned_dev() under device lock and never changes after, and 0 is never valid for a zoned device. Returning -EINVAL at init time fails device creation early with clear error, while defensive return 0 in null_zone_no() makes zoned command fail via offline zone check. No new locking is introduced. Reported-by: syzbot+abd6a8dca0f2b7726060@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=abd6a8dca0f2b7726060 Link: https://lore.kernel.org/all/6a75205c.01d0871a.3a0d52.0033.GAE@google.com/ Fixes: 8a3cf049af68 ("null_blk: add zoned block device emulation") Cc: stable@vger.kernel.org Assisted-by: Hermes:muse-spark-1.2 syzkaller Signed-off-by: Rik van Riel <riel@surriel.com> Reviewed-by: Damien Le Moal <dlemoal@kernel.org> Link: https://patch.msgid.link/20260808114239.69167f68@fangorn Signed-off-by: Jens Axboe <axboe@kernel.dk>
13 daysnull_blk: serialize configfs attribute updates with device setupNiklas Cassel
The attribute store methods generated with NULLB_DEVICE_ATTR() refuse to change the configuration of a live device by testing NULLB_DEV_FL_CONFIGURED, but that flag is only set by nullb_device_power_store() after null_add_dev() has returned, and the store methods take no lock at all. configfs only serializes writes to the same open file (buffer->mutex), so a write to any attribute can run concurrently with null_add_dev() and change the device configuration while it is being used. null_add_dev() reads the configuration several times, e.g. dev->zoned is read once to set up the queue limits and once to initialize the zone resources: CPU0: echo 1 > nullb0/power CPU1: echo 1 > nullb0/zoned nullb_device_power_store() mutex_lock(&lock) null_add_dev() if (dev->zoned) -> false /* no BLK_FEAT_ZONED */ nullb_device_zoned_store() test_bit(FL_CONFIGURED) -> 0 dev->zoned = true blk_mq_alloc_disk() /* queue is not zoned */ if (nullb->dev->zoned) -> true null_register_zoned_dev() blk_revalidate_disk_zones() blk_revalidate_disk_zones() is then called for a queue that does not have BLK_FEAT_ZONED set, which triggers its WARN_ON_ONCE() and fails the device setup with -EIO: WARNING: CPU: 2 PID: 322 at block/blk-zoned.c:2357 blk_revalidate_disk_zones+0x4c/0x560 Clearing dev->zoned in the same window is worse: the queue is created with BLK_FEAT_ZONED but the zone resources are never initialized, so add_disk() succeeds for a zoned disk that has no zones. And a store that lands after the last dev->zoned test leaves dev->zoned set while dev->zones is still NULL, which null_process_zoned_cmd() dereferences on the first write. Fix this by taking the global lock, which nullb_device_power_store() already holds across null_add_dev() and null_del_dev(), around both the NULLB_DEV_FL_CONFIGURED test and the update of the device configuration. The submit_queues and poll_queues apply callbacks are now called with that lock held, so remove the locking they did themselves. Since the store methods can run as soon as configfs_register_subsystem() returns, that is, before null_init() gets to mutex_init(&lock), also initialize the lock statically with DEFINE_MUTEX(). Fixes: 3bf2bd20734e ("nullb: add configfs interface") Reported-by: syzbot+643a6dd130546afdf1fb@syzkaller.appspotmail.com Closes: https://lore.kernel.org/linux-block/6a7d0b3f.ac361c09.22ff0a.004c.GAE@google.com/ Signed-off-by: Niklas Cassel <cassel@kernel.org> Reviewed-by: Damien Le Moal <dlemoal@kernel.org> Link: https://patch.msgid.link/20260813141456.1625857-2-cassel@kernel.org Signed-off-by: Jens Axboe <axboe@kernel.dk>
13 daysnull_blk: serialize configfs attribute shows with the lockZizhi Wo
The _show callback in the NULLB_DEVICE_ATTR macro reads dev->NAME and the _store path writes it. configfs does not serialize accesses across separate open file descriptions (buffer->mutex is per-fd), and _show takes no lock, so a concurrent read and write on the same attribute is a data race. The _show readers also race against writes to these fields that run after the configfs item becomes visible, e.g. in nullb_update_nr_hw_queues(). All of those writers now run under the file-scope lock: _store takes it unconditionally, and the setup-side writers run under power_store() which holds the same lock. The only remaining unsynchronized accesses are the plain reads in _show. Rather than annotating every field with READ_ONCE()/WRITE_ONCE() across files, simply take the file-scope lock in _show (and in power_show) as well. This closes the remaining _show-vs-write data races with a single lock and keeps the writers as plain assignments. configfs attribute access is not on the I/O hot path, so taking the mutex in _show is acceptable from a performance standpoint. The dev fields written in null_alloc_dev() and dev->power in nullb_group_drop_item() need no locking: the former runs from .make_group before the item is published, and the latter is serialized by configfs frag_sem/frag_dead against attribute show/store. Suggested-by: Nilay Shroff <nilay@linux.ibm.com> Suggested-by: Bart Van Assche <bvanassche@acm.org> Signed-off-by: Zizhi Wo <wozizhi@huawei.com> Reviewed-by: Nilay Shroff <nilay@linux.ibm.com> Link: https://patch.msgid.link/20260725022509.714271-11-wozizhi@huaweicloud.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
13 daysnull_blk: serialize configfs attribute stores with the lockZizhi Wo
The NULLB_DEVICE_ATTR _store takes no lock: apply_fn attributes (submit_queues, poll_queues) get dev->NAME written again after apply_fn returns, outside its lock; APPLY=NULL attributes are entirely lockless. configfs only serializes stores per-open-file, so concurrent stores on separate fds race. For apply_fn attributes, once one store's apply_fn has reconfigured the hardware, a second (losing) store can still overwrite dev->NAME afterwards. This leaves dev->submit_queues out of sync with the live queue count, which is later caught by the WARN_ON_ONCE() in null_map_queues(). For !apply_fn attributes, power_store()'s null_add_dev() validates and builds the device under "lock" but only sets CONFIGURED afterwards. A store slipping in during this window can change a field mid-setup -- for example, zone_nr_conv can be pushed above nr_zones after it has already been clamped, leading to an out-of-bounds dev->zones[] access. Take "lock" in the macro around the apply_fn call, the CONFIGURED test and the field write, and move it out of nullb_apply_submit_queues()/ nullb_apply_poll_queues() so both paths are covered once. This serializes stores with power_store's setup and with each other. Fixes: 45919fbfe1c4 ("null_blk: Enable modifying 'submit_queues' after an instance has been configured") Suggested-by: Bart Van Assche <bvanassche@acm.org> Signed-off-by: Zizhi Wo <wozizhi@huawei.com> Reviewed-by: Nilay Shroff <nilay@linux.ibm.com> Link: https://patch.msgid.link/20260725022509.714271-10-wozizhi@huaweicloud.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
13 daysnull_blk: convert file-scope mutex users to guard(mutex)Zizhi Wo
Using guard()/scoped_guard() ties lock release to scope exit, removing the need for manual mutex_unlock() calls and preventing missed unlocks on error paths. The per-attribute apply wrappers are left untouched, as those are reworked separately by the configfs show/store serialization patches. Signed-off-by: Zizhi Wo <wozizhi@huawei.com> Link: https://patch.msgid.link/20260725022509.714271-9-wozizhi@huaweicloud.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
13 daysnull_blk: reject per-device queue resize for shared tag setZizhi Wo
When shared_tags is enabled, null_setup_tagset() makes the device use the global tag_set, whose driver_data stays NULL. null_map_queues() therefore falls back to the module-wide g_submit_queues/g_poll_queues instead of any per-device value. Resizing submit_queues or poll_queues via configfs on such a device calls blk_mq_update_nr_hw_queues() on the shared set, shrinking set->nr_hw_queues. __blk_mq_realloc_hw_ctxs() only grows the q->queue_hw_ctx[] allocation, so on shrink it merely exits and NULLs the now-excess hctx slots. null_map_queues(), however, keeps mapping CPUs with the unchanged g_submit_queues/g_poll_queues, so mq_map[] ends up pointing at those NULLed hctx slots. blk_mq_map_swqueue() then dereferences the NULL hctx (hctx->cpumask), crashing the kernel: [ 460.218374] KASAN: null-ptr-deref in range [0x0000000000000098-0x000000000000009f] [ 460.219003] CPU: 24 UID: 0 PID: 1492 Comm: sh Not tainted 7.2.0-rc2+ #67 PREEMPT(full) [ 460.219792] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.17.0-4.fc41 04/01/2014 [ 460.220452] RIP: 0010:blk_mq_map_swqueue+0x4db/0x1430 ...... [ 460.228977] Call Trace: [ 460.229175] <TASK> [ 460.229354] blk_mq_update_nr_hw_queues+0xd49/0x11c0 [ 460.229779] ? __pfx_blk_mq_update_nr_hw_queues+0x10/0x10 [ 460.230200] nullb_update_nr_hw_queues+0x1a9/0x370 [null_blk] [ 460.230694] nullb_device_submit_queues_store+0xd9/0x170 [null_blk] [ 460.231190] ? __pfx_nullb_device_submit_queues_store+0x10/0x10 [null_blk] [ 460.231776] ? configfs_write_iter+0x35c/0x4e0 [ 460.232122] configfs_write_iter+0x286/0x4e0 [ 460.232460] vfs_write+0x52d/0xd00 [ 460.232779] ? __x64_sys_openat+0x108/0x1d0 [ 460.233106] ? __pfx_vfs_write+0x10/0x10 [ 460.233413] ? fdget_pos+0x1cf/0x4c0 [ 460.233745] ? fput_close+0x133/0x190 [ 460.234038] ? __pfx_expand_files+0x10/0x10 [ 460.234368] ksys_write+0xfc/0x1d0 Reproducer: modprobe null_blk shared_tags=1 submit_queues=64 poll_queues=1 mkdir /sys/kernel/config/nullb/dev echo 1 > /sys/kernel/config/nullb/dev/power echo 1 > /sys/kernel/config/nullb/dev/submit_queues A per-device resize of a shared tag set is meaningless anyway, so reject it with -EINVAL in nullb_update_nr_hw_queues() when the device is bound to the global tag_set. Fixes: 45919fbfe1c4 ("null_blk: Enable modifying 'submit_queues' after an instance has been configured") Suggested-by: Nilay Shroff <nilay@linux.ibm.com> Assisted-by: Claude-Code:GLM-5.2 Signed-off-by: Zizhi Wo <wozizhi@huawei.com> Reviewed-by: Nilay Shroff <nilay@linux.ibm.com> Reviewed-by: Bart Van Assche <bvanassche@acm.org> Link: https://patch.msgid.link/20260725022509.714271-8-wozizhi@huaweicloud.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
13 daysnull_blk: clean up null_del_dev() to use cached dev pointerZizhi Wo
Replace remaining nullb->dev dereferences with the already-cached local dev variable. No functional change. Signed-off-by: Zizhi Wo <wozizhi@huawei.com> Reviewed-by: Nilay Shroff <nilay@linux.ibm.com> Reviewed-by: Bart Van Assche <bvanassche@acm.org> Link: https://patch.msgid.link/20260725022509.714271-7-wozizhi@huaweicloud.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
13 daysnull_blk: free zones array on device power-offZizhi Wo
null_init_zoned_dev() allocates dev->zones when a zoned device is powered on, but null_del_dev() never frees it on power-off; dev->zones is only freed later in null_free_dev(), when the configfs directory is removed. If the device is powered off and then on again, null_init_zoned_dev() allocates a new array and overwrites the dev->zones pointer, leaking the previous allocation each power cycle. Free dev->zones in null_del_dev() via null_free_zoned_dev() to solve it. And calling null_free_zoned_dev() in null_free_dev() is no longer necessary because every caller already invokes null_del_dev() first: via nullb_group_drop_item() before nullb_device_release(), in the null_add_dev() error path of null_create_dev(), and in null_destroy_dev(). Remove the redundant call. And take &lock around zone_cond_store() in the two store wrappers to serialize dev->zones check-and-deref against its alloc/free, which already run under &lock. The reason there was no problem before is that only nullb_device_release() or null_exit() frees the dev->zones, which guarantees that subsequent users won't access the configfs interface. Fixes: ca4b2a011948 ("null_blk: add zone support") Assisted-by: Claude-Code:GLM-5.2 Signed-off-by: Zizhi Wo <wozizhi@huawei.com> Reviewed-by: Nilay Shroff <nilay@linux.ibm.com> Reviewed-by: Bart Van Assche <bvanassche@acm.org> Link: https://patch.msgid.link/20260725022509.714271-6-wozizhi@huaweicloud.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
13 daysnull_blk: free global tag_set on init error pathZizhi Wo
If shared_tags is enabled, null_setup_tagset() allocates the global tag_set via null_init_global_tag_set(). If device creation later fails, err_dev destroys the default devices and calls unregister_blkdev(), but never frees the global tag_set. Since module init failed, null_exit() is never invoked, so the global tag_set's tags and maps are permanently leaked. Free the global tag_set in err_dev, matching null_exit() which does if (tag_set.ops) blk_mq_free_tag_set(&tag_set). Fixes: 82f402fefa50 ("null_blk: add support for shared tags") Signed-off-by: Zizhi Wo <wozizhi@huawei.com> Reviewed-by: Damien Le Moal <dlemoal@kernel.org> Reviewed-by: Bart Van Assche <bvanassche@acm.org> Reviewed-by: Nilay Shroff <nilay@linux.ibm.com> Link: https://patch.msgid.link/20260725022509.714271-5-wozizhi@huaweicloud.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
13 daysnull_blk: move unregister_blkdev() after destroying dev in null_exit()Zizhi Wo
In null_exit(), unregister_blkdev() is called before the null_blk instances are destroyed, which is inconsistent with the cleanup order in null_init(). Move it after null_destroy_dev() so that teardown happens in the reverse order of initialization. No functional change intended. Suggested-by: Bart Van Assche <bvanassche@acm.org> Signed-off-by: Zizhi Wo <wozizhi@huawei.com> Reviewed-by: Damien Le Moal <dlemoal@kernel.org> Reviewed-by: Bart Van Assche <bvanassche@acm.org> Reviewed-by: Nilay Shroff <nilay@linux.ibm.com> Link: https://patch.msgid.link/20260725022509.714271-4-wozizhi@huaweicloud.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
13 daysnull_blk: register configfs subsystem after creating default devicesZizhi Wo
In null_init(), configfs_register_subsystem() currently runs before register_blkdev(), so when null_blk is built as a module, a racing mkdir() + poweron from userspace can reach null_add_dev() while null_major is still 0. __add_disk() then hits WARN_ON(disk->minors) (major=0 with minors!=0) and fails: [root@fedora ~]# [ 2366.521436] WARNING: block/genhd.c:476 at __add_disk+0x8a7/0xde0, [ 2366.523552] Modules linked in: null_blk(+) nft_fib_inet nft_fib_ipv4 nft_fib_ipv6 nft_fib [ 2366.529081] CPU: 26 UID: 0 PID: 1600 Comm: sh Not tainted 7.2.0-rc1+ #66 PREEMPT(full) ...... [ 2366.547251] Call Trace: [ 2366.547575] <TASK> [ 2366.547831] ? _raw_spin_lock+0x84/0xe0 [ 2366.548260] add_disk_fwnode+0x114/0x560 [ 2366.548739] null_add_dev+0x102d/0x1b80 [null_blk] [ 2366.549310] ? __pfx_null_add_dev+0x10/0x10 [null_blk] [ 2366.549906] ? mutex_lock+0xde/0x1c0 [ 2366.550361] ? __pfx_mutex_lock+0x10/0x10 [ 2366.550827] nullb_device_power_store+0x1e7/0x280 [null_blk] [ 2366.551499] ? __pfx_nullb_device_power_store+0x10/0x10 [null_blk] [ 2366.552177] ? __kmalloc_cache_noprof+0x1f5/0x470 [ 2366.552748] ? configfs_write_iter+0x35c/0x4e0 [ 2366.553242] configfs_write_iter+0x286/0x4e0 [ 2366.553787] vfs_write+0x52d/0xd00 [ 2366.554169] ? __pfx_vfs_write+0x10/0x10 [ 2366.554679] ? __pfx___css_rstat_updated+0x10/0x10 [ 2366.555196] ? fdget_pos+0x1cf/0x4c0 [ 2366.555649] ksys_write+0xfc/0x1d0 ...... Additionally, the err_dev path destroys all devices on nullb_list while configfs is still registered. If a racing mkdir() + poweron puts a user device on the list, null_destroy_dev()->null_free_dev() kfrees the user device's nullb_device but /sys/kernel/config/nullb/<name> is still reachable. Any userspace access to the item will trigger a UAF. For simplicity, move configfs_register_subsystem() to the end to solve the problems above. Fixes: 3bf2bd20734e ("nullb: add configfs interface") Signed-off-by: Zizhi Wo <wozizhi@huawei.com> Reviewed-by: Damien Le Moal <dlemoal@kernel.org> Reviewed-by: Bart Van Assche <bvanassche@acm.org> Reviewed-by: Nilay Shroff <nilay@linux.ibm.com> Link: https://patch.msgid.link/20260725022509.714271-3-wozizhi@huaweicloud.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
13 daysnull_blk: use DEFINE_MUTEX for the file-scope mutexZizhi Wo
In null_init(), mutex_init(&lock) currently happens after configfs_register_subsystem(), which exposes the nullb subsystem to userspace. A racing mkdir() into /sys/kernel/config/nullb/ can reach null_find_dev_by_name() -> mutex_lock(&lock) before the mutex is initialized, trigger warning: [ 123.137788] DEBUG_LOCKS_WARN_ON(lock->magic != lock) [ 123.137796] WARNING: kernel/locking/mutex.c:159 at mutex_lock+0x171/0x1c0, CPU#13: mkdir/1301 [ 123.140090] Modules linked in: null_blk(+) nft_fib_inet nft_fib_ipv4 ...... [ 123.154926] Call Trace: [ 123.155172] <TASK> [ 123.155419] ? __pfx_mutex_lock+0x10/0x10 [ 123.156181] ? __pfx__raw_spin_lock+0x10/0x10 [ 123.156571] nullb_group_make_group+0x20/0x100 [null_blk] [ 123.157011] configfs_mkdir+0x47b/0xc70 [ 123.157337] ? __pfx_configfs_mkdir+0x10/0x10 [ 123.157719] ? may_create_dentry+0x242/0x2e0 [ 123.158061] vfs_mkdir+0x2a9/0x6c0 [ 123.158352] filename_mkdirat+0x3dc/0x500 [ 123.158710] ? __pfx_filename_mkdirat+0x10/0x10 [ 123.159070] ? strncpy_from_user+0x3a/0x1d0 [ 123.159413] __x64_sys_mkdir+0x6b/0x90 [ 123.159760] do_syscall_64+0xea/0x600 Replace the runtime mutex_init(&lock) with a static DEFINE_MUTEX(lock) declaration to fix this issue. Fixes: 49c3b9266a71 ("block: null_blk: Improve device creation with configfs") Suggested-by: Bart Van Assche <bvanassche@acm.org> Signed-off-by: Zizhi Wo <wozizhi@huawei.com> Reviewed-by: Bart Van Assche <bvanassche@acm.org> Reviewed-by: Damien Le Moal <dlemoal@kernel.org> Reviewed-by: Nilay Shroff <nilay@linux.ibm.com> Link: https://patch.msgid.link/20260725022509.714271-2-wozizhi@huaweicloud.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2026-02-21Convert 'alloc_obj' family to use the new default GFP_KERNEL argumentLinus Torvalds
This was done entirely with mindless brute force, using git grep -l '\<k[vmz]*alloc_objs*(.*, GFP_KERNEL)' | xargs sed -i 's/\(alloc_objs*(.*\), GFP_KERNEL)/\1)/' to convert the new alloc_obj() users that had a simple GFP_KERNEL argument to just drop that argument. Note that due to the extreme simplicity of the scripting, any slightly more complex cases spread over multiple lines would not be triggered: they definitely exist, but this covers the vast bulk of the cases, and the resulting diff is also then easier to check automatically. For the same reason the 'flex' versions will be done as a separate conversion. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2026-02-21treewide: Replace kmalloc with kmalloc_obj for non-scalar typesKees Cook
This is the result of running the Coccinelle script from scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to avoid scalar types (which need careful case-by-case checking), and instead replace kmalloc-family calls that allocate struct or union object instances: Single allocations: kmalloc(sizeof(TYPE), ...) are replaced with: kmalloc_obj(TYPE, ...) Array allocations: kmalloc_array(COUNT, sizeof(TYPE), ...) are replaced with: kmalloc_objs(TYPE, COUNT, ...) Flex array allocations: kmalloc(struct_size(PTR, FAM, COUNT), ...) are replaced with: kmalloc_flex(*PTR, FAM, COUNT, ...) (where TYPE may also be *VAR) The resulting allocations no longer return "void *", instead returning "TYPE *". Signed-off-by: Kees Cook <kees@kernel.org>
2026-02-09Merge tag 'for-7.0/block-20260206' of ↵Linus Torvalds
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 ...
2026-01-13null_blk: fix kmemleak by releasing references to fault configfs itemsNilay Shroff
When CONFIG_BLK_DEV_NULL_BLK_FAULT_INJECTION is enabled, the null-blk driver sets up fault injection support by creating the timeout_inject, requeue_inject, and init_hctx_fault_inject configfs items as children of the top-level nullbX configfs group. However, when the nullbX device is removed, the references taken to these fault-config configfs items are not released. As a result, kmemleak reports a memory leak, for example: unreferenced object 0xc00000021ff25c40 (size 32): comm "mkdir", pid 10665, jiffies 4322121578 hex dump (first 32 bytes): 69 6e 69 74 5f 68 63 74 78 5f 66 61 75 6c 74 5f init_hctx_fault_ 69 6e 6a 65 63 74 00 88 00 00 00 00 00 00 00 00 inject.......... backtrace (crc 1a018c86): __kmalloc_node_track_caller_noprof+0x494/0xbd8 kvasprintf+0x74/0xf4 config_item_set_name+0xf0/0x104 config_group_init_type_name+0x48/0xfc fault_config_init+0x48/0xf0 0xc0080000180559e4 configfs_mkdir+0x304/0x814 vfs_mkdir+0x49c/0x604 do_mkdirat+0x314/0x3d0 sys_mkdir+0xa0/0xd8 system_call_exception+0x1b0/0x4f0 system_call_vectored_common+0x15c/0x2ec Fix this by explicitly releasing the references to the fault-config configfs items when dropping the reference to the top-level nullbX configfs group. Cc: stable@vger.kernel.org Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com> Fixes: bb4c19e030f4 ("block: null_blk: make fault-injection dynamically configurable per device") Signed-off-by: Nilay Shroff <nilay@linux.ibm.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-12-29null_blk: Constify struct configfs_item_operations and configfs_group_operationsChristophe JAILLET
'struct configfs_item_operations' and 'configfs_group_operations' are not modified in this driver. Constifying these structures moves some data to a read-only section, so increases overall security, especially when the structure holds some function pointers. On a x86_64, with allmodconfig: Before: ====== text data bss dec hex filename 100263 37808 2752 140823 22617 drivers/block/null_blk/main.o After: ===== text data bss dec hex filename 100423 37648 2752 140823 22617 drivers/block/null_blk/main.o Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-11-12null_blk: fix zone read length beyond write pointerKeith Busch
Fix up the divisor calculating the number of zone sectors being read and handle a read that straddles the zone write pointer. The length is rounded up a sector boundary, so be sure to truncate any excess bytes off to avoid copying past the data segment. Fixes: 3451cf34f51bb70 ("null_blk: allow byte aligned memory offsets") Signed-off-by: Keith Busch <kbusch@kernel.org> Tested-by: Bart van Assche <bvanassche@acm.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-11-06null_blk: allow byte aligned memory offsetsKeith Busch
Allowing byte aligned memory provides a nice testing ground for direct-io. Signed-off-by: Keith Busch <kbusch@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Damien Le Moal <dlemoal@kernel.org> Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com> Tested-by: Hans Holmberg <hans.holmberg@wdc.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-11-06null_blk: single kmap per bio segmentKeith Busch
Rather than kmap the the request bio segment for each sector, do the mapping just once. Signed-off-by: Keith Busch <kbusch@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Damien Le Moal <dlemoal@kernel.org> Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com> Tested-by: Hans Holmberg <hans.holmberg@wdc.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-11-06null_blk: consistently use blk_status_tKeith Busch
No need to mix errno and blk_status_t error types. Just use the standard block layer type. Signed-off-by: Keith Busch <kbusch@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Damien Le Moal <dlemoal@kernel.org> Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com> Tested-by: Hans Holmberg <hans.holmberg@wdc.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-11-06null_blk: simplify copy_from_nullbKeith Busch
It always returns success, so the code that saves the errors status, but proceeds without checking it looks a bit odd. Clean this up. Signed-off-by: Keith Busch <kbusch@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Damien Le Moal <dlemoal@kernel.org> Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com> Tested-by: Hans Holmberg <hans.holmberg@wdc.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-11-05block: introduce disk_report_zone()Damien Le Moal
Commit b76b840fd933 ("dm: Fix dm-zoned-reclaim zone write pointer alignment") introduced an indirect call for the callback function of a report zones executed with blkdev_report_zones(). This is necessary so that the function disk_zone_wplug_sync_wp_offset() can be called to refresh a zone write plug zone write pointer offset after a write error. However, this solution makes following the path of a zone information harder to understand. Clean this up by introducing the new blk_report_zones_args structure to define a zone report callback and its private data and introduce the helper function disk_report_zone() which calls both disk_zone_wplug_sync_wp_offset() and the zone report user callback function for all zones of a zone report. This helper function must be called by all block device drivers that implement the report zones block operation in order to correctly report a zone information. All block device drivers supporting the report_zones block operation are updated to use this new scheme. Signed-off-by: Damien Le Moal <dlemoal@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com> Reviewed-by: Hannes Reinecke <hare@suse.de> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-09-08null_blk: Fix the description of the cache_size module argumentGenjian Zhang
When executing modinfo null_blk, there is an error in the description of module parameter mbps, and the output information of cache_size is incomplete.The output of modinfo before and after applying this patch is as follows: Before: [...] parm: cache_size:ulong [...] parm: mbps:Cache size in MiB for memory-backed device. Default: 0 (none) (uint) [...] After: [...] parm: cache_size:Cache size in MiB for memory-backed device. Default: 0 (none) (ulong) [...] parm: mbps:Limit maximum bandwidth (in MiB/s). Default: 0 (no limit) (uint) [...] Fixes: 058efe000b31 ("null_blk: add module parameters for 4 options") Signed-off-by: Genjian Zhang <zhanggenjian@kylinos.cn> Reviewed-by: Damien Le Moal <dlemoal@kernel.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-07-09null_blk: use memzero_page()Matthew Wilcox (Oracle)
memzero_page() is the new name for zero_user(). Link: https://lkml.kernel.org/r/20250612143443.2848197-3-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Reviewed-by: Alex Markuze <amarkuze@redhat.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Ilya Dryomov <idryomov@gmail.com> Cc: Ira Weiny <ira.weiny@intel.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Xiubo Li <xiubli@redhat.com> Cc: Dan Carpenter <dan.carpenter@linaro.org> Cc: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-04-11null_blk: Use strscpy() instead of strscpy_pad() in null_add_dev()Thorsten Blum
blk_mq_alloc_disk() already zero-initializes the destination buffer, making strscpy() sufficient for safely copying the disk's name. The additional NUL-padding performed by strscpy_pad() is unnecessary. If the destination buffer has a fixed length, strscpy() automatically determines its size using sizeof() when the argument is omitted. This makes the explicit size argument unnecessary. The source string is also NUL-terminated and meets the __must_be_cstr() requirement of strscpy(). No functional changes intended. Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev> Reviewed-by: Zhu Yanjun <yanjun.zhu@linux.dev> Reviewed-by: Damien Le Moal <dlemoal@kernel.org> Link: https://lore.kernel.org/r/20250410154727.883207-1-thorsten.blum@linux.dev Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-03-26Merge tag 'for-6.15/block-20250322' of git://git.kernel.dk/linuxLinus Torvalds
Pull block updates from Jens Axboe: - Fixes for integrity handling - NVMe pull request via Keith: - Secure concatenation for TCP transport (Hannes) - Multipath sysfs visibility (Nilay) - Various cleanups (Qasim, Baruch, Wang, Chen, Mike, Damien, Li) - Correct use of 64-bit BARs for pci-epf target (Niklas) - Socket fix for selinux when used in containers (Peijie) - MD pull request via Yu: - fix recovery can preempt resync (Li Nan) - fix md-bitmap IO limit (Su Yue) - fix raid10 discard with REQ_NOWAIT (Xiao Ni) - fix raid1 memory leak (Zheng Qixing) - fix mddev uaf (Yu Kuai) - fix raid1,raid10 IO flags (Yu Kuai) - some refactor and cleanup (Yu Kuai) - Series cleaning up and fixing bugs in the bad block handling code - Improve support for write failure simulation in null_blk - Various lock ordering fixes - Fixes for locking for debugfs attributes - Various ublk related fixes and improvements - Cleanups for blk-rq-qos wait handling - blk-throttle fixes - Fixes for loop dio and sync handling - Fixes and cleanups for the auto-PI code - Block side support for hardware encryption keys in blk-crypto - Various cleanups and fixes * tag 'for-6.15/block-20250322' of git://git.kernel.dk/linux: (105 commits) nvmet: replace max(a, min(b, c)) by clamp(val, lo, hi) nvme-tcp: fix selinux denied when calling sock_sendmsg nvmet: pci-epf: Always configure BAR0 as 64-bit nvmet: Remove duplicate uuid_copy nvme: zns: Simplify nvme_zone_parse_entry() nvmet: pci-epf: Remove redundant 'flush_workqueue()' calls nvmet-fc: Remove unused functions nvme-pci: remove stale comment nvme-fc: Utilise min3() to simplify queue count calculation nvme-multipath: Add visibility for queue-depth io-policy nvme-multipath: Add visibility for numa io-policy nvme-multipath: Add visibility for round-robin io-policy nvmet: add tls_concat and tls_key debugfs entries nvmet-tcp: support secure channel concatenation nvmet: Add 'sq' argument to alloc_ctrl_args nvme-fabrics: reset admin connection for secure concatenation nvme-tcp: request secure channel concatenation nvme-keyring: add nvme_tls_psk_refresh() nvme: add nvme_auth_derive_tls_psk() nvme: add nvme_auth_generate_digest() ...
2025-03-25Merge tag 'timers-cleanups-2025-03-23' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull timer cleanups from Thomas Gleixner: "A treewide hrtimer timer cleanup hrtimers are initialized with hrtimer_init() and a subsequent store to the callback pointer. This turned out to be suboptimal for the upcoming Rust integration and is obviously a silly implementation to begin with. This cleanup replaces the hrtimer_init(T); T->function = cb; sequence with hrtimer_setup(T, cb); The conversion was done with Coccinelle and a few manual fixups. Once the conversion has completely landed in mainline, hrtimer_init() will be removed and the hrtimer::function becomes a private member" * tag 'timers-cleanups-2025-03-23' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (100 commits) wifi: rt2x00: Switch to use hrtimer_update_function() io_uring: Use helper function hrtimer_update_function() serial: xilinx_uartps: Use helper function hrtimer_update_function() ASoC: fsl: imx-pcm-fiq: Switch to use hrtimer_setup() RDMA: Switch to use hrtimer_setup() virtio: mem: Switch to use hrtimer_setup() drm/vmwgfx: Switch to use hrtimer_setup() drm/xe/oa: Switch to use hrtimer_setup() drm/vkms: Switch to use hrtimer_setup() drm/msm: Switch to use hrtimer_setup() drm/i915/request: Switch to use hrtimer_setup() drm/i915/uncore: Switch to use hrtimer_setup() drm/i915/pmu: Switch to use hrtimer_setup() drm/i915/perf: Switch to use hrtimer_setup() drm/i915/gvt: Switch to use hrtimer_setup() drm/i915/huc: Switch to use hrtimer_setup() drm/amdgpu: Switch to use hrtimer_setup() stm class: heartbeat: Switch to use hrtimer_setup() i2c: Switch to use hrtimer_setup() iio: Switch to use hrtimer_setup() ...
2025-03-12block: change blk_mq_add_to_batch() third argument type to boolShin'ichiro Kawasaki
Commit 1f47ed294a2b ("block: cleanup and fix batch completion adding conditions") modified the evaluation criteria for the third argument, 'ioerror', in the blk_mq_add_to_batch() function. Initially, the function had checked if 'ioerror' equals zero. Following the commit, it started checking for negative error values, with the presumption that such values, for instance -EIO, would be passed in. However, blk_mq_add_to_batch() callers do not pass negative error values. Instead, they pass status codes defined in various ways: - NVMe PCI and Apple drivers pass NVMe status code - virtio_blk driver passes the virtblk request header status byte - null_blk driver passes blk_status_t These codes are either zero or positive, therefore the revised check fails to function as intended. Specifically, with the NVMe PCI driver, this modification led to the failure of the blktests test case nvme/039. In this test scenario, errors are artificially injected to the NVMe driver, resulting in positive NVMe status codes passed to blk_mq_add_to_batch(), which unexpectedly processes the failed I/O in a batch. Hence the failure. To correct the ioerror check within blk_mq_add_to_batch(), make all callers to uniformly pass the argument as boolean. Modify the callers to check their specific status codes and pass the boolean value 'is_error'. Also describe the arguments of blK_mq_add_to_batch as kerneldoc. Fixes: 1f47ed294a2b ("block: cleanup and fix batch completion adding conditions") Signed-off-by: Shin'ichiro Kawasaki <shinichiro.kawasaki@wdc.com> Link: https://lore.kernel.org/r/20250311104359.1767728-3-shinichiro.kawasaki@wdc.com [axboe: fold in documentation update] Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-03-06badblocks: use sector_t instead of int to avoid truncation of badblocks lengthZheng Qixing
There is a truncation of badblocks length issue when set badblocks as follow: echo "2055 4294967299" > bad_blocks cat bad_blocks 2055 3 Change 'sectors' argument type from 'int' to 'sector_t'. This change avoids truncation of badblocks length for large sectors by replacing 'int' with 'sector_t' (u64), enabling proper handling of larger disk sizes and ensuring compatibility with 64-bit sector addressing. Fixes: 9e0e252a048b ("badblocks: Add core badblock management code") Signed-off-by: Zheng Qixing <zhengqixing@huawei.com> Reviewed-by: Yu Kuai <yukuai3@huawei.com> Acked-by: Coly Li <colyli@kernel.org> Link: https://lore.kernel.org/r/20250227075507.151331-13-zhengqixing@huaweicloud.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-03-06badblocks: return boolean from badblocks_set() and badblocks_clear()Zheng Qixing
Change the return type of badblocks_set() and badblocks_clear() from int to bool, indicating success or failure. Specifically: - _badblocks_set() and _badblocks_clear() functions now return true for success and false for failure. - All calls to these functions are updated to handle the new boolean return type. - This change improves code clarity and ensures a more consistent handling of success and failure states. Signed-off-by: Zheng Qixing <zhengqixing@huawei.com> Reviewed-by: Yu Kuai <yukuai3@huawei.com> Acked-by: Coly Li <colyli@kernel.org> Acked-by: Ira Weiny <ira.weiny@intel.com> Link: https://lore.kernel.org/r/20250227075507.151331-11-zhengqixing@huaweicloud.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-03-03null_blk: do partial IO for bad blocksShin'ichiro Kawasaki
The current null_blk implementation checks if any bad blocks exist in the target blocks of each IO. If so, the IO fails and data is not transferred for all of the IO target blocks. However, when real storage devices have bad blocks, the devices may transfer data partially up to the first bad blocks (e.g., SAS drives). Especially, when the IO is a write operation, such partial IO leaves partially written data on the device. To simulate such partial IO using null_blk, introduce the new parameter 'badblocks_partial_io'. When this parameter is set, null_handle_badblocks() returns the number of the sectors for the partial IO as its third pointer argument. Pass the returned number of sectors to the following calls to null_handle_memory_backend() in null_process_cmd() and null_zone_write(). Reviewed-by: Damien Le Moal <dlemoal@kernel.org> Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Signed-off-by: Shin'ichiro Kawasaki <shinichiro.kawasaki@wdc.com> Link: https://lore.kernel.org/r/20250226100613.1622564-6-shinichiro.kawasaki@wdc.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-03-03null_blk: pass transfer size to null_handle_rq()Shin'ichiro Kawasaki
As preparation to support partial data transfer, add a new argument to null_handle_rq() to pass the number of sectors to transfer. While at it, rename the function from null_handle_rq to null_handle_data_transfer. This commit does not change the behavior. Reviewed-by: Damien Le Moal <dlemoal@kernel.org> Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Signed-off-by: Shin'ichiro Kawasaki <shinichiro.kawasaki@wdc.com> Link: https://lore.kernel.org/r/20250226100613.1622564-5-shinichiro.kawasaki@wdc.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-03-03null_blk: replace null_process_cmd() call in null_zone_write()Shin'ichiro Kawasaki
As a preparation to support partial data transfer due to badblocks, replace the null_process_cmd() call in null_zone_write() with equivalent calls to null_handle_badblocks() and null_handle_memory_backed(). This commit does not change behavior. It will enable null_handle_badblocks() to return the size of partial data transfer in the following commit, allowing null_zone_write() to move write pointers appropriately. Reviewed-by: Damien Le Moal <dlemoal@kernel.org> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Signed-off-by: Shin'ichiro Kawasaki <shinichiro.kawasaki@wdc.com> Link: https://lore.kernel.org/r/20250226100613.1622564-4-shinichiro.kawasaki@wdc.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-03-03null_blk: introduce badblocks_once parameterShin'ichiro Kawasaki
When IO errors happen on real storage devices, the IOs repeated to the same target range can success by virtue of recovery features by devices, such as reserved block assignment. To simulate such IO errors and recoveries, introduce the new parameter badblocks_once parameter. When this parameter is set to 1, the specified badblocks are cleared after the first IO error, so that the next IO to the blocks succeed. Reviewed-by: Damien Le Moal <dlemoal@kernel.org> Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Signed-off-by: Shin'ichiro Kawasaki <shinichiro.kawasaki@wdc.com> Link: https://lore.kernel.org/r/20250226100613.1622564-3-shinichiro.kawasaki@wdc.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-03-03null_blk: generate null_blk configfs features stringShin'ichiro Kawasaki
The null_blk configfs file 'features' provides a string that lists available null_blk features for userspace programs to reference. The string is defined as a long constant in the code, which tends to be forgotten for updates. It also causes checkpatch.pl to report "WARNING: quoted string split across lines". To avoid these drawbacks, generate the feature string on the fly. Refer to the ca_name field of each element in the nullb_device_attrs table and concatenate them in the given buffer. Also, sorted nullb_device_attrs table elements in alphabetical order. Of note is that the feature "index" was missing before this commit. This commit adds it to the generated string. Suggested-by: Bart Van Assche <bvanassche@acm.org> Reviewed-by: Bart Van Assche <bvanassche@acm.org> Reviewed-by: Damien Le Moal <dlemoal@kernel.org> Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Signed-off-by: Shin'ichiro Kawasaki <shinichiro.kawasaki@wdc.com> Link: https://lore.kernel.org/r/20250226100613.1622564-2-shinichiro.kawasaki@wdc.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-02-18null_blk: Switch to use hrtimer_setup()Nam Cao
hrtimer_setup() takes the callback function pointer as argument and initializes the timer completely. Replace hrtimer_init() and the open coded initialization of hrtimer::function with the new setup mechanism. Patch was created by using Coccinelle. Signed-off-by: Nam Cao <namcao@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/all/076cd30acb4b2d6b699f3c80463a8983530d4f06.1738746821.git.namcao@linutronix.de
2025-01-06block: remove BLK_MQ_F_NO_SCHEDChristoph Hellwig
The only queues that really can't support a scheduler are those that do not have a gendisk associated with them, and thus can't be used for non-passthrough commands. In addition to those null_blk can optionally set the flag, which is a bad odd. Replace the null_blk usage with BLK_MQ_F_NO_SCHED_BY_DEFAULT to keep the expected semantics and then remove BLK_MQ_F_NO_SCHED as the non-disk queues never call into elevator_init_mq or blk_register_queue which adds the sysfs attributes. Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20250106083531.799976-4-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-12-23block: remove BLK_MQ_F_SHOULD_MERGEChristoph Hellwig
BLK_MQ_F_SHOULD_MERGE is set for all tag_sets except those that purely process passthrough commands (bsg-lib, ufs tmf, various nvme admin queues) and thus don't even check the flag. Remove it to simplify the driver interface. Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20241219060214.1928848-1-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-12-23null_blk: Remove accesses to page->indexMatthew Wilcox (Oracle)
Use page->private to store the index instead of page->index. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Reviewed-by: Damien Le Moal <dlemoal@kernel.org> Link: https://lore.kernel.org/r/20241216160849.31739-1-willy@infradead.org Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-12-23null_blk: Add rotational feature supportDamien Le Moal
To facilitate testing of kernel functions related to the rotational feature (BLK_FEAT_ROTATIONAL) of a block device (e.g. NVMe rotational bit support), add the rotational boolean configfs attribute and module parameter to the null_blk driver. If set, a null block device will report being a rotational device through it queue limits features with the BLK_FEAT_ROTATIONAL flag. Signed-off-by: Damien Le Moal <dlemoal@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Hannes Reinecke <hare@suse.de> Link: https://lore.kernel.org/r/20241126000956.95983-1-dlemoal@kernel.org Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-11-13block: add a rq_list typeChristoph Hellwig
Replace the semi-open coded request list helpers with a proper rq_list type that mirrors the bio_list and has head and tail pointers. Besides better type safety this actually allows to insert at the tail of the list, which will be useful soon. Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20241113152050.157179-5-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-11-11block: pre-calculate max_zone_append_sectorsChristoph Hellwig
max_zone_append_sectors differs from all other queue limits in that the final value used is not stored in the queue_limits but needs to be obtained using queue_limits_max_zone_append_sectors helper. This not only adds (tiny) extra overhead to the I/O path, but also can be easily forgotten in file system code. Add a new max_hw_zone_append_sectors value to queue_limits which is set by the driver, and calculate max_zone_append_sectors from that and the other inputs in blk_validate_zoned_limits, similar to how max_sectors is calculated to fix this. Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20241104073955.112324-3-hch@lst.de Reviewed-by: Damien Le Moal <dlemoal@kernel.org> Link: https://lore.kernel.org/r/20241108154657.845768-2-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-11-07Revert "block: pre-calculate max_zone_append_sectors"Jens Axboe
This causes issue on, at least, nvme-mpath where my boot fails with: WARNING: CPU: 354 PID: 2729 at block/blk-settings.c:75 blk_validate_limits+0x356/0x380 Modules linked in: tg3(+) nvme usbcore scsi_mod ptp i2c_piix4 libphy nvme_core crc32c_intel scsi_common usb_common pps_core i2c_smbus CPU: 354 UID: 0 PID: 2729 Comm: kworker/u2061:1 Not tainted 6.12.0-rc6+ #181 Hardware name: Dell Inc. PowerEdge R7625/06444F, BIOS 1.8.3 04/02/2024 Workqueue: async async_run_entry_fn RIP: 0010:blk_validate_limits+0x356/0x380 Code: f6 47 01 04 75 28 83 bf 94 00 00 00 00 75 39 83 bf 98 00 00 00 00 75 34 83 7f 68 00 75 32 31 c0 83 7f 5c 00 0f 84 9b fd ff ff <0f> 0b eb 13 0f 0b eb 0f 48 c7 c0 74 12 58 92 48 89 c7 e8 13 76 46 RSP: 0018:ffffa8a1dfb93b30 EFLAGS: 00010286 RAX: 0000000000000000 RBX: ffff9232829c8388 RCX: 0000000000000088 RDX: 0000000000000080 RSI: 0000000000000200 RDI: ffffa8a1dfb93c38 RBP: 000000000000000c R08: 00000000ffffffff R09: 000000000000ffff R10: 0000000000000000 R11: 0000000000000000 R12: ffff9232829b9000 R13: ffff9232829b9010 R14: ffffa8a1dfb93c38 R15: ffffa8a1dfb93c38 FS: 0000000000000000(0000) GS:ffff923867c80000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055c1b92480a8 CR3: 0000002484ff0002 CR4: 0000000000370ef0 Call Trace: <TASK> ? __warn+0xca/0x1a0 ? blk_validate_limits+0x356/0x380 ? report_bug+0x11a/0x1a0 ? handle_bug+0x5e/0x90 ? exc_invalid_op+0x16/0x40 ? asm_exc_invalid_op+0x16/0x20 ? blk_validate_limits+0x356/0x380 blk_alloc_queue+0x7a/0x250 __blk_alloc_disk+0x39/0x80 nvme_mpath_alloc_disk+0x13d/0x1b0 [nvme_core] nvme_scan_ns+0xcc7/0x1010 [nvme_core] async_run_entry_fn+0x27/0x120 process_scheduled_works+0x1a0/0x360 worker_thread+0x2bc/0x350 ? pr_cont_work+0x1b0/0x1b0 kthread+0x111/0x120 ? kthread_unuse_mm+0x90/0x90 ret_from_fork+0x30/0x40 ? kthread_unuse_mm+0x90/0x90 ret_from_fork_asm+0x11/0x20 </TASK> ---[ end trace 0000000000000000 ]--- presumably due to max_zone_append_sectors not being cleared to zero, resulting in blk_validate_zoned_limits() complaining and failing. This reverts commit 2a8f6153e1c2db06a537a5c9d61102eb591776f1. Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-11-04block: pre-calculate max_zone_append_sectorsChristoph Hellwig
max_zone_append_sectors differs from all other queue limits in that the final value used is not stored in the queue_limits but needs to be obtained using queue_limits_max_zone_append_sectors helper. This not only adds (tiny) extra overhead to the I/O path, but also can be easily forgotten in file system code. Add a new max_hw_zone_append_sectors value to queue_limits which is set by the driver, and calculate max_zone_append_sectors from that and the other inputs in blk_validate_zoned_limits, similar to how max_sectors is calculated to fix this. Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20241104073955.112324-3-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-07-09null_blk: Don't bother validating blocksizeJohn Garry
The block queue limits validation does this for us now. Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: John Garry <john.g.garry@oracle.com> Reviewed-by: Zhu Yanjun <yanjun.zhu@linux.dev> Reviewed-by: Damien Le Moal <dlemoal@kernel.org> Acked-by: Michael S. Tsirkin <mst@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Link: https://lore.kernel.org/r/20240708091651.177447-4-john.g.garry@oracle.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-07-05block: Remove REQ_OP_ZONE_RESET_ALL emulationDamien Le Moal
Now that device mapper can handle resetting all zones of a mapped zoned device using REQ_OP_ZONE_RESET_ALL, all zoned block device drivers support this operation. With this, the request queue feature BLK_FEAT_ZONE_RESETALL is not necessary and the emulation code in blk-zone.c can be removed. Signed-off-by: Damien Le Moal <dlemoal@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Link: https://lore.kernel.org/r/20240704052816.623865-5-dlemoal@kernel.org Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-07-05null_blk: Introduce the zone_full parameterDamien Le Moal
Allow creating a zoned null_blk device with the initial state of its sequential write required zones to be FULL. This is convenient to avoid having to first write these zones to perform read performance evaluation or test zone management operations such as zone reset (and zone reset all). Signed-off-by: Damien Le Moal <dlemoal@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Link: https://lore.kernel.org/r/20240704052816.623865-2-dlemoal@kernel.org Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-07-04null_blk: don't initialize static 'g_virt_boundary' to falseZhu Yanjun
No functional changes intended. Signed-off-by: Zhu Yanjun <yanjun.zhu@linux.dev> Link: https://lore.kernel.org/r/20240704010638.324349-1-yanjun.zhu@linux.dev Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-07-02null_blk: Fix description of the fua parameterDamien Le Moal
The description of the fua module parameter is defined using MODULE_PARM_DESC() with the first argument passed being "zoned". That is the wrong name, obviously. Fix that by using the correct "fua" parameter name so that "modinfo null_blk" displays correct information. Fixes: f4f84586c8b9 ("null_blk: Introduce fua attribute") Cc: stable@vger.kernel.org Signed-off-by: Damien Le Moal <dlemoal@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com> Link: https://lore.kernel.org/r/20240702073234.206458-1-dlemoal@kernel.org Signed-off-by: Jens Axboe <axboe@kernel.dk>