kernel/linux.git/drivers/md/raid1.h, branch v6.19.11

md/raid1: convert to use bio_submit_split_bioset()

2025-09-10T11:23:45+00:00

Unify bio split code, and prepare to fix ordering of split IO. Noted that bio_submit_split_bioset() can fail the original bio directly by split error, set R1BIO_Returned in this case to notify raid_end_bio_io() that the original bio is returned already. Signed-off-by: Yu Kuai Reviewed-by: Christoph Hellwig Signed-off-by: Jens Axboe

md/raid1: remove struct pool_info and related code

2025-08-03T05:08:12+00:00

The struct pool_info was originally introduced mainly to support reshape operations, serving as a parameter for mempool_init() when raid_disks changes. Now that mempool_create_kmalloc_pool() is sufficient for this purpose, struct pool_info and its related code are no longer needed. Remove struct pool_info and all associated code. Signed-off-by: Wang Jinchao Link: https://lore.kernel.org/linux-raid/20250707012711.376844-3-yukuai1@huaweicloud.com Signed-off-by: Yu Kuai

md/raid1: change r1conf->r1bio_pool to a pointer type

2025-08-03T05:08:02+00:00

In raid1_reshape(), newpool is a stack variable. mempool_init() initializes newpool->wait with the stack address. After assigning newpool to conf->r1bio_pool, the wait queue need to be reinitialized, which is not ideal. Change raid1_conf->r1bio_pool to a pointer type and replace mempool_init() with mempool_create_kmalloc_pool() to avoid referencing a stack-based wait queue. Signed-off-by: Wang Jinchao Link: https://lore.kernel.org/linux-raid/20250707012711.376844-2-yukuai1@huaweicloud.com Signed-off-by: Yu Kuai

md/md-bitmap: remove the last parameter for bimtap_ops->endwrite()

2025-01-13T16:56:10+00:00

For the case that IO failed for one rdev, the bit will be mark as NEEDED in following cases: 1) If badblocks is set and rdev is not faulty; 2) If rdev is faulty; Case 1) is useless because synchronize data to badblocks make no sense. Case 2) can be replaced with mddev->degraded. Also remove R1BIO_Degraded, R10BIO_Degraded and STRIPE_DEGRADED since case 2) no longer use them. Signed-off-by: Yu Kuai Link: https://lore.kernel.org/r/20250109015145.158868-3-yukuai1@huaweicloud.com Signed-off-by: Song Liu

md/raid1: record nonrot rdevs while adding/removing rdevs to conf

2024-03-01T06:49:45+00:00

For raid1, each read will iterate all the rdevs from conf and check if any rdev is non-rotational, then choose rdev with minimal IO inflight if so, or rdev with closest distance otherwise. Disk nonrot info can be changed through sysfs entry: /sys/block/[disk_name]/queue/rotational However, consider that this should only be used for testing, and user really shouldn't do this in real life. Record the number of non-rotational disks in conf, to avoid checking each rdev in IO fast path and simplify read_balance() a little bit. Co-developed-by: Paul Luse Signed-off-by: Paul Luse Signed-off-by: Yu Kuai Signed-off-by: Song Liu Link: https://lore.kernel.org/r/20240229095714.926789-4-yukuai1@huaweicloud.com

md/raid1: switch to use md_account_bio() for io accounting

2023-07-27T07:13:29+00:00

Two problems can be fixed this way: 1) 'active_io' will represent inflight io instead of io that is dispatching. 2) If io accounting is enabled or disabled while io is still inflight, bio_start_io_acct() and bio_end_io_acct() is not balanced and io inflight counter will be leaked. Signed-off-by: Yu Kuai Reviewed-by: Xiao Ni Signed-off-by: Song Liu Link: https://lore.kernel.org/r/20230621165110.1498313-5-yukuai1@huaweicloud.com

md: protect md_thread with rcu

2023-06-13T22:25:39+00:00

Currently, there are many places that md_thread can be accessed without protection, following are known scenarios that can cause null-ptr-dereference or uaf: 1) sync_thread that is allocated and started from md_start_sync() 2) mddev->thread can be accessed directly from timeout_store() and md_bitmap_daemon_work() 3) md_unregister_thread() from action_store(). Currently, a global spinlock 'pers_lock' is borrowed to protect 'mddev->thread' in some places, this problem can be fixed likewise, however, use a global lock for all the cases is not good. Fix this problem by protecting all md_thread with rcu. Signed-off-by: Yu Kuai Signed-off-by: Song Liu Link: https://lore.kernel.org/r/20230523021017.3048783-6-yukuai1@huaweicloud.com

md: raid1/raid10: drop pending_cnt

2022-03-08T23:16:54+00:00

Those counters are not necessary after commit 11bb45e8aaf6 ("md: drop queue limitation for RAID1 and RAID10"). Remove them from all code (conf and plug structs). raid1_plug_cb and raid10_plug_cb are identical, so move definition of raid1_plug_cb to common raid1-10 definitions and use it for RAID10 too. Signed-off-by: Mariusz Tkaczyk Signed-off-by: Song Liu

md/raid1: enable io accounting

2021-06-15T05:32:07+00:00

For raid1, we record the start time between split bio and clone bio, and finish the accounting in the final endio. Also introduce start_time in r1bio accordingly. Signed-off-by: Guoqing Jiang Signed-off-by: Song Liu

md/raid1: Replace zero-length array with flexible-array

2020-05-13T19:02:23+00:00

The current codebase makes use of the zero-length array language extension to the C90 standard, but the preferred mechanism to declare variable-length types such as these ones is a flexible array member[1][2], introduced in C99: struct foo { int stuff; struct boo array[]; }; By making use of the mechanism above, we will get a compiler warning in case the flexible array does not occur last in the structure, which will help us prevent some kind of undefined behavior bugs from being inadvertently introduced[3] to the codebase from now on. Also, notice that, dynamic memory allocations won't be affected by this change: "Flexible array members have incomplete type, and so the sizeof operator may not be applied. As a quirk of the original implementation of zero-length arrays, sizeof evaluates to zero."[1] sizeof(flexible-array-member) triggers a warning because flexible array members have incomplete type[1]. There are some instances of code in which the sizeof operator is being incorrectly/erroneously applied to zero-length arrays and the result is zero. Such instances may be hiding some bugs. So, this work (flexible-array member conversions) will also help to get completely rid of those sorts of issues. This issue was found with the help of Coccinelle. [1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html [2] https://github.com/KSPP/linux/issues/21 [3] commit 76497732932f ("cxgb3/l2t: Fix undefined behaviour") Signed-off-by: Gustavo A. R. Silva Signed-off-by: Song Liu