linux/block/blk-lib.c

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License cleanup: add SPDX GPL-2.0 license identifier to files with no license 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 <kstewart@linuxfoundation.org> Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-01 14:07:57 +00:00
// SPDX-License-Identifier: GPL-2.0
/*
* Functions related to generic helpers functions
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/bio.h>
#include <linux/blkdev.h>
#include <linux/scatterlist.h>
#include "blk.h"
static sector_t bio_discard_limit(struct block_device *bdev, sector_t sector)
{
unsigned int discard_granularity = bdev_discard_granularity(bdev);
sector_t granularity_aligned_sector;
if (bdev_is_partition(bdev))
sector += bdev->bd_start_sect;
granularity_aligned_sector =
round_up(sector, discard_granularity >> SECTOR_SHIFT);
/*
* Make sure subsequent bios start aligned to the discard granularity if
* it needs to be split.
*/
if (granularity_aligned_sector != sector)
return granularity_aligned_sector - sector;
/*
* Align the bio size to the discard granularity to make splitting the bio
* at discard granularity boundaries easier in the driver if needed.
*/
return round_down(UINT_MAX, discard_granularity) >> SECTOR_SHIFT;
}
int __blkdev_issue_discard(struct block_device *bdev, sector_t sector,
sector_t nr_sects, gfp_t gfp_mask, struct bio **biop)
{
struct bio *bio = *biop;
sector_t bs_mask;
if (bdev_read_only(bdev))
return -EPERM;
if (!bdev_max_discard_sectors(bdev))
return -EOPNOTSUPP;
block: check queue's limits.discard_granularity in __blkdev_issue_discard() If create a loop device with a backing NVMe SSD, current loop device driver doesn't correctly set its queue's limits.discard_granularity and leaves it as 0. If a discard request at LBA 0 on this loop device, in __blkdev_issue_discard() the calculated req_sects will be 0, and a zero length discard request will trigger a BUG() panic in generic block layer code at block/blk-mq.c:563. [ 955.565006][ C39] ------------[ cut here ]------------ [ 955.559660][ C39] invalid opcode: 0000 [#1] SMP NOPTI [ 955.622171][ C39] CPU: 39 PID: 248 Comm: ksoftirqd/39 Tainted: G E 5.8.0-default+ #40 [ 955.622171][ C39] Hardware name: Lenovo ThinkSystem SR650 -[7X05CTO1WW]-/-[7X05CTO1WW]-, BIOS -[IVE160M-2.70]- 07/17/2020 [ 955.622175][ C39] RIP: 0010:blk_mq_end_request+0x107/0x110 [ 955.622177][ C39] Code: 48 8b 03 e9 59 ff ff ff 48 89 df 5b 5d 41 5c e9 9f ed ff ff 48 8b 35 98 3c f4 00 48 83 c7 10 48 83 c6 19 e8 cb 56 c9 ff eb cb <0f> 0b 0f 1f 80 00 00 00 00 0f 1f 44 00 00 55 48 89 e5 41 56 41 54 [ 955.622179][ C39] RSP: 0018:ffffb1288701fe28 EFLAGS: 00010202 [ 955.749277][ C39] RAX: 0000000000000001 RBX: ffff956fffba5080 RCX: 0000000000004003 [ 955.749278][ C39] RDX: 0000000000000003 RSI: 0000000000000000 RDI: 0000000000000000 [ 955.749279][ C39] RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 [ 955.749279][ C39] R10: ffffb1288701fd28 R11: 0000000000000001 R12: ffffffffa8e05160 [ 955.749280][ C39] R13: 0000000000000004 R14: 0000000000000004 R15: ffffffffa7ad3a1e [ 955.749281][ C39] FS: 0000000000000000(0000) GS:ffff95bfbda00000(0000) knlGS:0000000000000000 [ 955.749282][ C39] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 955.749282][ C39] CR2: 00007f6f0ef766a8 CR3: 0000005a37012002 CR4: 00000000007606e0 [ 955.749283][ C39] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 955.749284][ C39] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 955.749284][ C39] PKRU: 55555554 [ 955.749285][ C39] Call Trace: [ 955.749290][ C39] blk_done_softirq+0x99/0xc0 [ 957.550669][ C39] __do_softirq+0xd3/0x45f [ 957.550677][ C39] ? smpboot_thread_fn+0x2f/0x1e0 [ 957.550679][ C39] ? smpboot_thread_fn+0x74/0x1e0 [ 957.550680][ C39] ? smpboot_thread_fn+0x14e/0x1e0 [ 957.550684][ C39] run_ksoftirqd+0x30/0x60 [ 957.550687][ C39] smpboot_thread_fn+0x149/0x1e0 [ 957.886225][ C39] ? sort_range+0x20/0x20 [ 957.886226][ C39] kthread+0x137/0x160 [ 957.886228][ C39] ? kthread_park+0x90/0x90 [ 957.886231][ C39] ret_from_fork+0x22/0x30 [ 959.117120][ C39] ---[ end trace 3dacdac97e2ed164 ]--- This is the procedure to reproduce the panic, # modprobe scsi_debug delay=0 dev_size_mb=2048 max_queue=1 # losetup -f /dev/nvme0n1 --direct-io=on # blkdiscard /dev/loop0 -o 0 -l 0x200 This patch fixes the issue by checking q->limits.discard_granularity in __blkdev_issue_discard() before composing the discard bio. If the value is 0, then prints a warning oops information and returns -EOPNOTSUPP to the caller to indicate that this buggy device driver doesn't support discard request. Fixes: 9b15d109a6b2 ("block: improve discard bio alignment in __blkdev_issue_discard()") Fixes: c52abf563049 ("loop: Better discard support for block devices") Reported-and-suggested-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Coly Li <colyli@suse.de> Reviewed-by: Ming Lei <ming.lei@redhat.com> Reviewed-by: Hannes Reinecke <hare@suse.de> Reviewed-by: Jack Wang <jinpu.wang@cloud.ionos.com> Cc: Bart Van Assche <bvanassche@acm.org> Cc: Christoph Hellwig <hch@lst.de> Cc: Darrick J. Wong <darrick.wong@oracle.com> Cc: Enzo Matsumiya <ematsumiya@suse.com> Cc: Evan Green <evgreen@chromium.org> Cc: Jens Axboe <axboe@kernel.dk> Cc: Martin K. Petersen <martin.petersen@oracle.com> Cc: Xiao Ni <xni@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-08-05 17:25:03 +00:00
/* In case the discard granularity isn't set by buggy device driver */
if (WARN_ON_ONCE(!bdev_discard_granularity(bdev))) {
pr_err_ratelimited("%pg: Error: discard_granularity is 0.\n",
bdev);
block: check queue's limits.discard_granularity in __blkdev_issue_discard() If create a loop device with a backing NVMe SSD, current loop device driver doesn't correctly set its queue's limits.discard_granularity and leaves it as 0. If a discard request at LBA 0 on this loop device, in __blkdev_issue_discard() the calculated req_sects will be 0, and a zero length discard request will trigger a BUG() panic in generic block layer code at block/blk-mq.c:563. [ 955.565006][ C39] ------------[ cut here ]------------ [ 955.559660][ C39] invalid opcode: 0000 [#1] SMP NOPTI [ 955.622171][ C39] CPU: 39 PID: 248 Comm: ksoftirqd/39 Tainted: G E 5.8.0-default+ #40 [ 955.622171][ C39] Hardware name: Lenovo ThinkSystem SR650 -[7X05CTO1WW]-/-[7X05CTO1WW]-, BIOS -[IVE160M-2.70]- 07/17/2020 [ 955.622175][ C39] RIP: 0010:blk_mq_end_request+0x107/0x110 [ 955.622177][ C39] Code: 48 8b 03 e9 59 ff ff ff 48 89 df 5b 5d 41 5c e9 9f ed ff ff 48 8b 35 98 3c f4 00 48 83 c7 10 48 83 c6 19 e8 cb 56 c9 ff eb cb <0f> 0b 0f 1f 80 00 00 00 00 0f 1f 44 00 00 55 48 89 e5 41 56 41 54 [ 955.622179][ C39] RSP: 0018:ffffb1288701fe28 EFLAGS: 00010202 [ 955.749277][ C39] RAX: 0000000000000001 RBX: ffff956fffba5080 RCX: 0000000000004003 [ 955.749278][ C39] RDX: 0000000000000003 RSI: 0000000000000000 RDI: 0000000000000000 [ 955.749279][ C39] RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 [ 955.749279][ C39] R10: ffffb1288701fd28 R11: 0000000000000001 R12: ffffffffa8e05160 [ 955.749280][ C39] R13: 0000000000000004 R14: 0000000000000004 R15: ffffffffa7ad3a1e [ 955.749281][ C39] FS: 0000000000000000(0000) GS:ffff95bfbda00000(0000) knlGS:0000000000000000 [ 955.749282][ C39] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 955.749282][ C39] CR2: 00007f6f0ef766a8 CR3: 0000005a37012002 CR4: 00000000007606e0 [ 955.749283][ C39] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 955.749284][ C39] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 955.749284][ C39] PKRU: 55555554 [ 955.749285][ C39] Call Trace: [ 955.749290][ C39] blk_done_softirq+0x99/0xc0 [ 957.550669][ C39] __do_softirq+0xd3/0x45f [ 957.550677][ C39] ? smpboot_thread_fn+0x2f/0x1e0 [ 957.550679][ C39] ? smpboot_thread_fn+0x74/0x1e0 [ 957.550680][ C39] ? smpboot_thread_fn+0x14e/0x1e0 [ 957.550684][ C39] run_ksoftirqd+0x30/0x60 [ 957.550687][ C39] smpboot_thread_fn+0x149/0x1e0 [ 957.886225][ C39] ? sort_range+0x20/0x20 [ 957.886226][ C39] kthread+0x137/0x160 [ 957.886228][ C39] ? kthread_park+0x90/0x90 [ 957.886231][ C39] ret_from_fork+0x22/0x30 [ 959.117120][ C39] ---[ end trace 3dacdac97e2ed164 ]--- This is the procedure to reproduce the panic, # modprobe scsi_debug delay=0 dev_size_mb=2048 max_queue=1 # losetup -f /dev/nvme0n1 --direct-io=on # blkdiscard /dev/loop0 -o 0 -l 0x200 This patch fixes the issue by checking q->limits.discard_granularity in __blkdev_issue_discard() before composing the discard bio. If the value is 0, then prints a warning oops information and returns -EOPNOTSUPP to the caller to indicate that this buggy device driver doesn't support discard request. Fixes: 9b15d109a6b2 ("block: improve discard bio alignment in __blkdev_issue_discard()") Fixes: c52abf563049 ("loop: Better discard support for block devices") Reported-and-suggested-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Coly Li <colyli@suse.de> Reviewed-by: Ming Lei <ming.lei@redhat.com> Reviewed-by: Hannes Reinecke <hare@suse.de> Reviewed-by: Jack Wang <jinpu.wang@cloud.ionos.com> Cc: Bart Van Assche <bvanassche@acm.org> Cc: Christoph Hellwig <hch@lst.de> Cc: Darrick J. Wong <darrick.wong@oracle.com> Cc: Enzo Matsumiya <ematsumiya@suse.com> Cc: Evan Green <evgreen@chromium.org> Cc: Jens Axboe <axboe@kernel.dk> Cc: Martin K. Petersen <martin.petersen@oracle.com> Cc: Xiao Ni <xni@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-08-05 17:25:03 +00:00
return -EOPNOTSUPP;
}
bs_mask = (bdev_logical_block_size(bdev) >> 9) - 1;
if ((sector | nr_sects) & bs_mask)
return -EINVAL;
if (!nr_sects)
return -EINVAL;
while (nr_sects) {
sector_t req_sects =
min(nr_sects, bio_discard_limit(bdev, sector));
bio = blk_next_bio(bio, bdev, 0, REQ_OP_DISCARD, gfp_mask);
block: Abstract out bvec iterator Immutable biovecs are going to require an explicit iterator. To implement immutable bvecs, a later patch is going to add a bi_bvec_done member to this struct; for now, this patch effectively just renames things. Signed-off-by: Kent Overstreet <kmo@daterainc.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: "Ed L. Cashin" <ecashin@coraid.com> Cc: Nick Piggin <npiggin@kernel.dk> Cc: Lars Ellenberg <drbd-dev@lists.linbit.com> Cc: Jiri Kosina <jkosina@suse.cz> Cc: Matthew Wilcox <willy@linux.intel.com> Cc: Geoff Levand <geoff@infradead.org> Cc: Yehuda Sadeh <yehuda@inktank.com> Cc: Sage Weil <sage@inktank.com> Cc: Alex Elder <elder@inktank.com> Cc: ceph-devel@vger.kernel.org Cc: Joshua Morris <josh.h.morris@us.ibm.com> Cc: Philip Kelleher <pjk1939@linux.vnet.ibm.com> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Jeremy Fitzhardinge <jeremy@goop.org> Cc: Neil Brown <neilb@suse.de> Cc: Alasdair Kergon <agk@redhat.com> Cc: Mike Snitzer <snitzer@redhat.com> Cc: dm-devel@redhat.com Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: linux390@de.ibm.com Cc: Boaz Harrosh <bharrosh@panasas.com> Cc: Benny Halevy <bhalevy@tonian.com> Cc: "James E.J. Bottomley" <JBottomley@parallels.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "Nicholas A. Bellinger" <nab@linux-iscsi.org> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Chris Mason <chris.mason@fusionio.com> Cc: "Theodore Ts'o" <tytso@mit.edu> Cc: Andreas Dilger <adilger.kernel@dilger.ca> Cc: Jaegeuk Kim <jaegeuk.kim@samsung.com> Cc: Steven Whitehouse <swhiteho@redhat.com> Cc: Dave Kleikamp <shaggy@kernel.org> Cc: Joern Engel <joern@logfs.org> Cc: Prasad Joshi <prasadjoshi.linux@gmail.com> Cc: Trond Myklebust <Trond.Myklebust@netapp.com> Cc: KONISHI Ryusuke <konishi.ryusuke@lab.ntt.co.jp> Cc: Mark Fasheh <mfasheh@suse.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: Ben Myers <bpm@sgi.com> Cc: xfs@oss.sgi.com Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Len Brown <len.brown@intel.com> Cc: Pavel Machek <pavel@ucw.cz> Cc: "Rafael J. Wysocki" <rjw@sisk.pl> Cc: Herton Ronaldo Krzesinski <herton.krzesinski@canonical.com> Cc: Ben Hutchings <ben@decadent.org.uk> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Guo Chao <yan@linux.vnet.ibm.com> Cc: Tejun Heo <tj@kernel.org> Cc: Asai Thambi S P <asamymuthupa@micron.com> Cc: Selvan Mani <smani@micron.com> Cc: Sam Bradshaw <sbradshaw@micron.com> Cc: Wei Yongjun <yongjun_wei@trendmicro.com.cn> Cc: "Roger Pau Monné" <roger.pau@citrix.com> Cc: Jan Beulich <jbeulich@suse.com> Cc: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Cc: Ian Campbell <Ian.Campbell@citrix.com> Cc: Sebastian Ott <sebott@linux.vnet.ibm.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Jiang Liu <jiang.liu@huawei.com> Cc: Nitin Gupta <ngupta@vflare.org> Cc: Jerome Marchand <jmarchand@redhat.com> Cc: Joe Perches <joe@perches.com> Cc: Peng Tao <tao.peng@emc.com> Cc: Andy Adamson <andros@netapp.com> Cc: fanchaoting <fanchaoting@cn.fujitsu.com> Cc: Jie Liu <jeff.liu@oracle.com> Cc: Sunil Mushran <sunil.mushran@gmail.com> Cc: "Martin K. Petersen" <martin.petersen@oracle.com> Cc: Namjae Jeon <namjae.jeon@samsung.com> Cc: Pankaj Kumar <pankaj.km@samsung.com> Cc: Dan Magenheimer <dan.magenheimer@oracle.com> Cc: Mel Gorman <mgorman@suse.de>6
2013-10-11 22:44:27 +00:00
bio->bi_iter.bi_sector = sector;
bio->bi_iter.bi_size = req_sects << 9;
sector += req_sects;
nr_sects -= req_sects;
/*
* We can loop for a long time in here, if someone does
* full device discards (like mkfs). Be nice and allow
* us to schedule out to avoid softlocking if preempt
* is disabled.
*/
cond_resched();
}
*biop = bio;
return 0;
}
EXPORT_SYMBOL(__blkdev_issue_discard);
/**
* blkdev_issue_discard - queue a discard
* @bdev: blockdev to issue discard for
* @sector: start sector
* @nr_sects: number of sectors to discard
* @gfp_mask: memory allocation flags (for bio_alloc)
*
* Description:
* Issue a discard request for the sectors in question.
*/
int blkdev_issue_discard(struct block_device *bdev, sector_t sector,
sector_t nr_sects, gfp_t gfp_mask)
{
struct bio *bio = NULL;
struct blk_plug plug;
int ret;
blk_start_plug(&plug);
ret = __blkdev_issue_discard(bdev, sector, nr_sects, gfp_mask, &bio);
if (!ret && bio) {
ret = submit_bio_wait(bio);
if (ret == -EOPNOTSUPP)
ret = 0;
bio_put(bio);
}
blk_finish_plug(&plug);
return ret;
}
EXPORT_SYMBOL(blkdev_issue_discard);
static int __blkdev_issue_write_zeroes(struct block_device *bdev,
sector_t sector, sector_t nr_sects, gfp_t gfp_mask,
struct bio **biop, unsigned flags)
{
struct bio *bio = *biop;
unsigned int max_write_zeroes_sectors;
if (bdev_read_only(bdev))
return -EPERM;
/* Ensure that max_write_zeroes_sectors doesn't overflow bi_size */
max_write_zeroes_sectors = bdev_write_zeroes_sectors(bdev);
if (max_write_zeroes_sectors == 0)
return -EOPNOTSUPP;
while (nr_sects) {
bio = blk_next_bio(bio, bdev, 0, REQ_OP_WRITE_ZEROES, gfp_mask);
bio->bi_iter.bi_sector = sector;
if (flags & BLKDEV_ZERO_NOUNMAP)
bio->bi_opf |= REQ_NOUNMAP;
if (nr_sects > max_write_zeroes_sectors) {
bio->bi_iter.bi_size = max_write_zeroes_sectors << 9;
nr_sects -= max_write_zeroes_sectors;
sector += max_write_zeroes_sectors;
} else {
bio->bi_iter.bi_size = nr_sects << 9;
nr_sects = 0;
}
cond_resched();
}
*biop = bio;
return 0;
}
/*
* Convert a number of 512B sectors to a number of pages.
* The result is limited to a number of pages that can fit into a BIO.
* Also make sure that the result is always at least 1 (page) for the cases
* where nr_sects is lower than the number of sectors in a page.
*/
static unsigned int __blkdev_sectors_to_bio_pages(sector_t nr_sects)
{
sector_t pages = DIV_ROUND_UP_SECTOR_T(nr_sects, PAGE_SIZE / 512);
return min(pages, (sector_t)BIO_MAX_VECS);
}
static int __blkdev_issue_zero_pages(struct block_device *bdev,
sector_t sector, sector_t nr_sects, gfp_t gfp_mask,
struct bio **biop)
{
struct bio *bio = *biop;
int bi_size = 0;
unsigned int sz;
if (bdev_read_only(bdev))
return -EPERM;
while (nr_sects != 0) {
bio = blk_next_bio(bio, bdev, __blkdev_sectors_to_bio_pages(nr_sects),
REQ_OP_WRITE, gfp_mask);
bio->bi_iter.bi_sector = sector;
while (nr_sects != 0) {
sz = min((sector_t) PAGE_SIZE, nr_sects << 9);
bi_size = bio_add_page(bio, ZERO_PAGE(0), sz, 0);
nr_sects -= bi_size >> 9;
sector += bi_size >> 9;
if (bi_size < sz)
break;
}
cond_resched();
}
*biop = bio;
return 0;
}
/**
* __blkdev_issue_zeroout - generate number of zero filed write bios
* @bdev: blockdev to issue
* @sector: start sector
* @nr_sects: number of sectors to write
* @gfp_mask: memory allocation flags (for bio_alloc)
* @biop: pointer to anchor bio
* @flags: controls detailed behavior
*
* Description:
* Zero-fill a block range, either using hardware offload or by explicitly
* writing zeroes to the device.
*
* If a device is using logical block provisioning, the underlying space will
* not be released if %flags contains BLKDEV_ZERO_NOUNMAP.
*
* If %flags contains BLKDEV_ZERO_NOFALLBACK, the function will return
* -EOPNOTSUPP if no explicit hardware offload for zeroing is provided.
*/
int __blkdev_issue_zeroout(struct block_device *bdev, sector_t sector,
sector_t nr_sects, gfp_t gfp_mask, struct bio **biop,
unsigned flags)
{
int ret;
sector_t bs_mask;
bs_mask = (bdev_logical_block_size(bdev) >> 9) - 1;
if ((sector | nr_sects) & bs_mask)
return -EINVAL;
ret = __blkdev_issue_write_zeroes(bdev, sector, nr_sects, gfp_mask,
biop, flags);
if (ret != -EOPNOTSUPP || (flags & BLKDEV_ZERO_NOFALLBACK))
return ret;
return __blkdev_issue_zero_pages(bdev, sector, nr_sects, gfp_mask,
biop);
}
EXPORT_SYMBOL(__blkdev_issue_zeroout);
/**
* blkdev_issue_zeroout - zero-fill a block range
* @bdev: blockdev to write
* @sector: start sector
* @nr_sects: number of sectors to write
* @gfp_mask: memory allocation flags (for bio_alloc)
* @flags: controls detailed behavior
*
* Description:
* Zero-fill a block range, either using hardware offload or by explicitly
* writing zeroes to the device. See __blkdev_issue_zeroout() for the
* valid values for %flags.
*/
int blkdev_issue_zeroout(struct block_device *bdev, sector_t sector,
sector_t nr_sects, gfp_t gfp_mask, unsigned flags)
{
int ret = 0;
sector_t bs_mask;
struct bio *bio;
struct blk_plug plug;
bool try_write_zeroes = !!bdev_write_zeroes_sectors(bdev);
bs_mask = (bdev_logical_block_size(bdev) >> 9) - 1;
if ((sector | nr_sects) & bs_mask)
return -EINVAL;
retry:
bio = NULL;
blk_start_plug(&plug);
if (try_write_zeroes) {
ret = __blkdev_issue_write_zeroes(bdev, sector, nr_sects,
gfp_mask, &bio, flags);
} else if (!(flags & BLKDEV_ZERO_NOFALLBACK)) {
ret = __blkdev_issue_zero_pages(bdev, sector, nr_sects,
gfp_mask, &bio);
} else {
/* No zeroing offload support */
ret = -EOPNOTSUPP;
}
if (ret == 0 && bio) {
ret = submit_bio_wait(bio);
bio_put(bio);
}
blk_finish_plug(&plug);
if (ret && try_write_zeroes) {
if (!(flags & BLKDEV_ZERO_NOFALLBACK)) {
try_write_zeroes = false;
goto retry;
}
if (!bdev_write_zeroes_sectors(bdev)) {
/*
* Zeroing offload support was indicated, but the
* device reported ILLEGAL REQUEST (for some devices
* there is no non-destructive way to verify whether
* WRITE ZEROES is actually supported).
*/
ret = -EOPNOTSUPP;
}
}
return ret;
}
EXPORT_SYMBOL(blkdev_issue_zeroout);
int blkdev_issue_secure_erase(struct block_device *bdev, sector_t sector,
sector_t nr_sects, gfp_t gfp)
{
sector_t bs_mask = (bdev_logical_block_size(bdev) >> 9) - 1;
unsigned int max_sectors = bdev_max_secure_erase_sectors(bdev);
struct bio *bio = NULL;
struct blk_plug plug;
int ret = 0;
/* make sure that "len << SECTOR_SHIFT" doesn't overflow */
if (max_sectors > UINT_MAX >> SECTOR_SHIFT)
max_sectors = UINT_MAX >> SECTOR_SHIFT;
max_sectors &= ~bs_mask;
if (max_sectors == 0)
return -EOPNOTSUPP;
if ((sector | nr_sects) & bs_mask)
return -EINVAL;
if (bdev_read_only(bdev))
return -EPERM;
blk_start_plug(&plug);
while (nr_sects) {
unsigned int len = min_t(sector_t, nr_sects, max_sectors);
bio = blk_next_bio(bio, bdev, 0, REQ_OP_SECURE_ERASE, gfp);
bio->bi_iter.bi_sector = sector;
bio->bi_iter.bi_size = len << SECTOR_SHIFT;
sector += len;
nr_sects -= len;
cond_resched();
}
if (bio) {
ret = submit_bio_wait(bio);
bio_put(bio);
}
blk_finish_plug(&plug);
return ret;
}
EXPORT_SYMBOL(blkdev_issue_secure_erase);