kernel-aes67/drivers/md/raid1-10.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 10:07:57 -04:00
// SPDX-License-Identifier: GPL-2.0
/* Maximum size of each resync request */
#define RESYNC_BLOCK_SIZE (64*1024)
#define RESYNC_PAGES ((RESYNC_BLOCK_SIZE + PAGE_SIZE-1) / PAGE_SIZE)
/*
* Number of guaranteed raid bios in case of extreme VM load:
*/
#define NR_RAID_BIOS 256
/* when we get a read error on a read-only array, we redirect to another
* device without failing the first device, or trying to over-write to
* correct the read error. To keep track of bad blocks on a per-bio
* level, we store IO_BLOCKED in the appropriate 'bios' pointer
*/
#define IO_BLOCKED ((struct bio *)1)
/* When we successfully write to a known bad-block, we need to remove the
* bad-block marking which must be done from process context. So we record
* the success by setting devs[n].bio to IO_MADE_GOOD
*/
#define IO_MADE_GOOD ((struct bio *)2)
#define BIO_SPECIAL(bio) ((unsigned long)bio <= 2)
#define MAX_PLUG_BIO 32
/* for managing resync I/O pages */
struct resync_pages {
void *raid_bio;
struct page *pages[RESYNC_PAGES];
};
struct raid1_plug_cb {
struct blk_plug_cb cb;
struct bio_list pending;
unsigned int count;
};
static void rbio_pool_free(void *rbio, void *data)
{
kfree(rbio);
}
static inline int resync_alloc_pages(struct resync_pages *rp,
gfp_t gfp_flags)
{
int i;
for (i = 0; i < RESYNC_PAGES; i++) {
rp->pages[i] = alloc_page(gfp_flags);
if (!rp->pages[i])
goto out_free;
}
return 0;
out_free:
while (--i >= 0)
put_page(rp->pages[i]);
return -ENOMEM;
}
static inline void resync_free_pages(struct resync_pages *rp)
{
int i;
for (i = 0; i < RESYNC_PAGES; i++)
put_page(rp->pages[i]);
}
static inline void resync_get_all_pages(struct resync_pages *rp)
{
int i;
for (i = 0; i < RESYNC_PAGES; i++)
get_page(rp->pages[i]);
}
static inline struct page *resync_fetch_page(struct resync_pages *rp,
unsigned idx)
{
if (WARN_ON_ONCE(idx >= RESYNC_PAGES))
return NULL;
return rp->pages[idx];
}
/*
* 'strct resync_pages' stores actual pages used for doing the resync
* IO, and it is per-bio, so make .bi_private points to it.
*/
static inline struct resync_pages *get_resync_pages(struct bio *bio)
{
return bio->bi_private;
}
/* generally called after bio_reset() for reseting bvec */
static void md_bio_reset_resync_pages(struct bio *bio, struct resync_pages *rp,
int size)
{
int idx = 0;
/* initialize bvec table again */
do {
struct page *page = resync_fetch_page(rp, idx);
int len = min_t(int, size, PAGE_SIZE);
if (WARN_ON(!bio_add_page(bio, page, len, 0))) {
bio->bi_status = BLK_STS_RESOURCE;
bio_endio(bio);
return;
}
size -= len;
} while (idx++ < RESYNC_PAGES && size > 0);
}
static inline void raid1_submit_write(struct bio *bio)
{
struct md_rdev *rdev = (void *)bio->bi_bdev;
bio->bi_next = NULL;
bio_set_dev(bio, rdev->bdev);
if (test_bit(Faulty, &rdev->flags))
bio_io_error(bio);
else if (unlikely(bio_op(bio) == REQ_OP_DISCARD &&
!bdev_max_discard_sectors(bio->bi_bdev)))
/* Just ignore it */
bio_endio(bio);
else
submit_bio_noacct(bio);
}
static inline bool raid1_add_bio_to_plug(struct mddev *mddev, struct bio *bio,
blk_plug_cb_fn unplug, int copies)
{
struct raid1_plug_cb *plug = NULL;
struct blk_plug_cb *cb;
/*
* If bitmap is not enabled, it's safe to submit the io directly, and
* this can get optimal performance.
*/
if (!md_bitmap_enabled(mddev->bitmap)) {
raid1_submit_write(bio);
return true;
}
cb = blk_check_plugged(unplug, mddev, sizeof(*plug));
if (!cb)
return false;
plug = container_of(cb, struct raid1_plug_cb, cb);
bio_list_add(&plug->pending, bio);
if (++plug->count / MAX_PLUG_BIO >= copies) {
list_del(&cb->list);
cb->callback(cb, false);
}
return true;
}
/*
* current->bio_list will be set under submit_bio() context, in this case bitmap
* io will be added to the list and wait for current io submission to finish,
* while current io submission must wait for bitmap io to be done. In order to
* avoid such deadlock, submit bitmap io asynchronously.
*/
static inline void raid1_prepare_flush_writes(struct bitmap *bitmap)
{
if (current->bio_list)
md_bitmap_unplug_async(bitmap);
else
md_bitmap_unplug(bitmap);
}
/*
* Used by fix_read_error() to decay the per rdev read_errors.
* We halve the read error count for every hour that has elapsed
* since the last recorded read error.
*/
static inline void check_decay_read_errors(struct mddev *mddev, struct md_rdev *rdev)
{
long cur_time_mon;
unsigned long hours_since_last;
unsigned int read_errors = atomic_read(&rdev->read_errors);
cur_time_mon = ktime_get_seconds();
if (rdev->last_read_error == 0) {
/* first time we've seen a read error */
rdev->last_read_error = cur_time_mon;
return;
}
hours_since_last = (long)(cur_time_mon -
rdev->last_read_error) / 3600;
rdev->last_read_error = cur_time_mon;
/*
* if hours_since_last is > the number of bits in read_errors
* just set read errors to 0. We do this to avoid
* overflowing the shift of read_errors by hours_since_last.
*/
if (hours_since_last >= 8 * sizeof(read_errors))
atomic_set(&rdev->read_errors, 0);
else
atomic_set(&rdev->read_errors, read_errors >> hours_since_last);
}
static inline bool exceed_read_errors(struct mddev *mddev, struct md_rdev *rdev)
{
int max_read_errors = atomic_read(&mddev->max_corr_read_errors);
int read_errors;
check_decay_read_errors(mddev, rdev);
read_errors = atomic_inc_return(&rdev->read_errors);
if (read_errors > max_read_errors) {
pr_notice("md/"RAID_1_10_NAME":%s: %pg: Raid device exceeded read_error threshold [cur %d:max %d]\n",
mdname(mddev), rdev->bdev, read_errors, max_read_errors);
pr_notice("md/"RAID_1_10_NAME":%s: %pg: Failing raid device\n",
mdname(mddev), rdev->bdev);
md_error(mddev, rdev);
return true;
}
return false;
}
/**
* raid1_check_read_range() - check a given read range for bad blocks,
* available read length is returned;
* @rdev: the rdev to read;
* @this_sector: read position;
* @len: read length;
*
* helper function for read_balance()
*
* 1) If there are no bad blocks in the range, @len is returned;
* 2) If the range are all bad blocks, 0 is returned;
* 3) If there are partial bad blocks:
* - If the bad block range starts after @this_sector, the length of first
* good region is returned;
* - If the bad block range starts before @this_sector, 0 is returned and
* the @len is updated to the offset into the region before we get to the
* good blocks;
*/
static inline int raid1_check_read_range(struct md_rdev *rdev,
sector_t this_sector, int *len)
{
sector_t first_bad;
int bad_sectors;
/* no bad block overlap */
if (!is_badblock(rdev, this_sector, *len, &first_bad, &bad_sectors))
return *len;
/*
* bad block range starts offset into our range so we can return the
* number of sectors before the bad blocks start.
*/
if (first_bad > this_sector)
return first_bad - this_sector;
/* read range is fully consumed by bad blocks. */
if (this_sector + *len <= first_bad + bad_sectors)
return 0;
/*
* final case, bad block range starts before or at the start of our
* range but does not cover our entire range so we still return 0 but
* update the length with the number of sectors before we get to the
* good ones.
*/
*len = first_bad + bad_sectors - this_sector;
return 0;
}
/*
* Check if read should choose the first rdev.
*
* Balance on the whole device if no resync is going on (recovery is ok) or
* below the resync window. Otherwise, take the first readable disk.
*/
static inline bool raid1_should_read_first(struct mddev *mddev,
sector_t this_sector, int len)
{
if ((mddev->recovery_cp < this_sector + len))
return true;
if (mddev_is_clustered(mddev) &&
md_cluster_ops->area_resyncing(mddev, READ, this_sector,
this_sector + len))
return true;
return false;
}