kernel/linux.git/drivers/md/raid1.h, branch v6.6.132

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

2025-02-21T12:57:26+00:00

commit 4f0e7d0e03b7b80af84759a9e7cfb0f81ac4adae upstream. 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 [ Resolve minor conflicts ] Signed-off-by: Yu Kuai Signed-off-by: Greg Kroah-Hartman

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

md: convert to bioset_init()/mempool_init()

2018-05-30T21:33:32+00:00

Convert md to embedded bio sets. Signed-off-by: Kent Overstreet Signed-off-by: Jens Axboe

md: document lifetime of internal rdev pointer.

2018-02-18T18:22:27+00:00

The rdev pointer kept in the local 'config' for each for raid1, raid10, raid4/5/6 has non-obvious lifetime rules. Sometimes RCU is needed, sometimes a lock, something nothing. Add documentation to explain this. Signed-off-by: NeilBrown Signed-off-by: Shaohua Li

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

2017-11-02T10:10:55+00:00

Many source files in the tree are missing licensing information, which makes it harder for compliance tools to determine the correct license. By default all files without license information are under the default license of the kernel, which is GPL version 2. Update the files which contain no license information with the 'GPL-2.0' SPDX license identifier. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. How this work was done: Patches were generated and checked against linux-4.14-rc6 for a subset of the use cases: - file had no licensing information it it. - file was a */uapi/* one with no licensing information in it, - file was a */uapi/* one with existing licensing information, Further patches will be generated in subsequent months to fix up cases where non-standard license headers were used, and references to license had to be inferred by heuristics based on keywords. The analysis to determine which SPDX License Identifier to be applied to a file was done in a spreadsheet of side by side results from of the output of two independent scanners (ScanCode & Windriver) producing SPDX tag:value files created by Philippe Ombredanne. Philippe prepared the base worksheet, and did an initial spot review of a few 1000 files. The 4.13 kernel was the starting point of the analysis with 60,537 files assessed. Kate Stewart did a file by file comparison of the scanner results in the spreadsheet to determine which SPDX license identifier(s) to be applied to the file. She confirmed any determination that was not immediately clear with lawyers working with the Linux Foundation. Criteria used to select files for SPDX license identifier tagging was: - Files considered eligible had to be source code files. - Make and config files were included as candidates if they contained >5 lines of source - File already had some variant of a license header in it (even if <5 lines). All documentation files were explicitly excluded. The following heuristics were used to determine which SPDX license identifiers to apply. - when both scanners couldn't find any license traces, file was considered to have no license information in it, and the top level COPYING file license applied. For non */uapi/* files that summary was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 11139 and resulted in the first patch in this series. If that file was a */uapi/* path one, it was "GPL-2.0 WITH Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 WITH Linux-syscall-note 930 and resulted in the second patch in this series. - if a file had some form of licensing information in it, and was one of the */uapi/* ones, it was denoted with the Linux-syscall-note if any GPL family license was found in the file or had no licensing in it (per prior point). Results summary: SPDX license identifier # files ---------------------------------------------------|------ GPL-2.0 WITH Linux-syscall-note 270 GPL-2.0+ WITH Linux-syscall-note 169 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17 LGPL-2.1+ WITH Linux-syscall-note 15 GPL-1.0+ WITH Linux-syscall-note 14 ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5 LGPL-2.0+ WITH Linux-syscall-note 4 LGPL-2.1 WITH Linux-syscall-note 3 ((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3 ((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1 and that resulted in the third patch in this series. - when the two scanners agreed on the detected license(s), that became the concluded license(s). - when there was disagreement between the two scanners (one detected a license but the other didn't, or they both detected different licenses) a manual inspection of the file occurred. - In most cases a manual inspection of the information in the file resulted in a clear resolution of the license that should apply (and which scanner probably needed to revisit its heuristics). - When it was not immediately clear, the license identifier was confirmed with lawyers working with the Linux Foundation. - If there was any question as to the appropriate license identifier, the file was flagged for further research and to be revisited later in time. In total, over 70 hours of logged manual review was done on the spreadsheet to determine the SPDX license identifiers to apply to the source files by Kate, Philippe, Thomas and, in some cases, confirmation by lawyers working with the Linux Foundation. Kate also obtained a third independent scan of the 4.13 code base from FOSSology, and compared selected files where the other two scanners disagreed against that SPDX file, to see if there was new insights. The Windriver scanner is based on an older version of FOSSology in part, so they are related. Thomas did random spot checks in about 500 files from the spreadsheets for the uapi headers and agreed with SPDX license identifier in the files he inspected. For the non-uapi files Thomas did random spot checks in about 15000 files. In initial set of patches against 4.14-rc6, 3 files were found to have copy/paste license identifier errors, and have been fixed to reflect the correct identifier. Additionally Philippe spent 10 hours this week doing a detailed manual inspection and review of the 12,461 patched files from the initial patch version early this week with: - a full scancode scan run, collecting the matched texts, detected license ids and scores - reviewing anything where there was a license detected (about 500+ files) to ensure that the applied SPDX license was correct - reviewing anything where there was no detection but the patch license was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied SPDX license was correct This produced a worksheet with 20 files needing minor correction. This worksheet was then exported into 3 different .csv files for the different types of files to be modified. These .csv files were then reviewed by Greg. Thomas wrote a script to parse the csv files and add the proper SPDX tag to the file, in the format that the file expected. This script was further refined by Greg based on the output to detect more types of files automatically and to distinguish between header and source .c files (which need different comment types.) Finally Greg ran the script using the .csv files to generate the patches. Reviewed-by: Kate Stewart Reviewed-by: Philippe Ombredanne Reviewed-by: Thomas Gleixner Signed-off-by: Greg Kroah-Hartman

md/raid1: Use a new variable to count flighting sync requests

2017-04-27T21:01:16+00:00

In new barrier codes, raise_barrier waits if conf->nr_pending[idx] is not zero. After all the conditions are true, the resync request can go on be handled. But it adds conf->nr_pending[idx] again. The next resync request hit the same bucket idx need to wait the resync request which is submitted before. The performance of resync/recovery is degraded. So we should use a new variable to count sync requests which are in flight. I did a simple test: 1. Without the patch, create a raid1 with two disks. The resync speed: Device: rrqm/s wrqm/s r/s w/s rMB/s wMB/s avgrq-sz avgqu-sz await r_await w_await svctm %util sdb 0.00 0.00 166.00 0.00 10.38 0.00 128.00 0.03 0.20 0.20 0.00 0.19 3.20 sdc 0.00 0.00 0.00 166.00 0.00 10.38 128.00 0.96 5.77 0.00 5.77 5.75 95.50 2. With the patch, the result is: sdb 2214.00 0.00 766.00 0.00 185.69 0.00 496.46 2.80 3.66 3.66 0.00 1.03 79.10 sdc 0.00 2205.00 0.00 769.00 0.00 186.44 496.52 5.25 6.84 0.00 6.84 1.30 100.10 Suggested-by: Shaohua Li Signed-off-by: Xiao Ni Acked-by: Coly Li Signed-off-by: Shaohua Li