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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 10:05:51 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 10:05:51 +0000
commit5d1646d90e1f2cceb9f0828f4b28318cd0ec7744 (patch)
treea94efe259b9009378be6d90eb30d2b019d95c194 /block/blk-lib.c
parentInitial commit. (diff)
downloadlinux-upstream/5.10.209.tar.xz
linux-upstream/5.10.209.zip
Adding upstream version 5.10.209.upstream/5.10.209upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'block/blk-lib.c')
-rw-r--r--block/blk-lib.c441
1 files changed, 441 insertions, 0 deletions
diff --git a/block/blk-lib.c b/block/blk-lib.c
new file mode 100644
index 000000000..e90614fd8
--- /dev/null
+++ b/block/blk-lib.c
@@ -0,0 +1,441 @@
+// 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"
+
+struct bio *blk_next_bio(struct bio *bio, unsigned int nr_pages, gfp_t gfp)
+{
+ struct bio *new = bio_alloc(gfp, nr_pages);
+
+ if (bio) {
+ bio_chain(bio, new);
+ submit_bio(bio);
+ }
+
+ return new;
+}
+
+int __blkdev_issue_discard(struct block_device *bdev, sector_t sector,
+ sector_t nr_sects, gfp_t gfp_mask, int flags,
+ struct bio **biop)
+{
+ struct request_queue *q = bdev_get_queue(bdev);
+ struct bio *bio = *biop;
+ unsigned int op;
+ sector_t bs_mask, part_offset = 0;
+
+ if (!q)
+ return -ENXIO;
+
+ if (bdev_read_only(bdev))
+ return -EPERM;
+
+ if (flags & BLKDEV_DISCARD_SECURE) {
+ if (!blk_queue_secure_erase(q))
+ return -EOPNOTSUPP;
+ op = REQ_OP_SECURE_ERASE;
+ } else {
+ if (!blk_queue_discard(q))
+ return -EOPNOTSUPP;
+ op = REQ_OP_DISCARD;
+ }
+
+ /* In case the discard granularity isn't set by buggy device driver */
+ if (WARN_ON_ONCE(!q->limits.discard_granularity)) {
+ char dev_name[BDEVNAME_SIZE];
+
+ bdevname(bdev, dev_name);
+ pr_err_ratelimited("%s: Error: discard_granularity is 0.\n", dev_name);
+ return -EOPNOTSUPP;
+ }
+
+ bs_mask = (bdev_logical_block_size(bdev) >> 9) - 1;
+ if ((sector | nr_sects) & bs_mask)
+ return -EINVAL;
+
+ if (!nr_sects)
+ return -EINVAL;
+
+ /* In case the discard request is in a partition */
+ if (bdev_is_partition(bdev))
+ part_offset = bdev->bd_part->start_sect;
+
+ while (nr_sects) {
+ sector_t granularity_aligned_lba, req_sects;
+ sector_t sector_mapped = sector + part_offset;
+
+ granularity_aligned_lba = round_up(sector_mapped,
+ q->limits.discard_granularity >> SECTOR_SHIFT);
+
+ /*
+ * Check whether the discard bio starts at a discard_granularity
+ * aligned LBA,
+ * - If no: set (granularity_aligned_lba - sector_mapped) to
+ * bi_size of the first split bio, then the second bio will
+ * start at a discard_granularity aligned LBA on the device.
+ * - If yes: use bio_aligned_discard_max_sectors() as the max
+ * possible bi_size of the first split bio. Then when this bio
+ * is split in device drive, the split ones are very probably
+ * to be aligned to discard_granularity of the device's queue.
+ */
+ if (granularity_aligned_lba == sector_mapped)
+ req_sects = min_t(sector_t, nr_sects,
+ bio_aligned_discard_max_sectors(q));
+ else
+ req_sects = min_t(sector_t, nr_sects,
+ granularity_aligned_lba - sector_mapped);
+
+ WARN_ON_ONCE((req_sects << 9) > UINT_MAX);
+
+ bio = blk_next_bio(bio, 0, gfp_mask);
+ bio->bi_iter.bi_sector = sector;
+ bio_set_dev(bio, bdev);
+ bio_set_op_attrs(bio, op, 0);
+
+ 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)
+ * @flags: BLKDEV_DISCARD_* flags to control behaviour
+ *
+ * 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, unsigned long flags)
+{
+ struct bio *bio = NULL;
+ struct blk_plug plug;
+ int ret;
+
+ blk_start_plug(&plug);
+ ret = __blkdev_issue_discard(bdev, sector, nr_sects, gfp_mask, flags,
+ &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);
+
+/**
+ * __blkdev_issue_write_same - generate number of bios with same page
+ * @bdev: target blockdev
+ * @sector: start sector
+ * @nr_sects: number of sectors to write
+ * @gfp_mask: memory allocation flags (for bio_alloc)
+ * @page: page containing data to write
+ * @biop: pointer to anchor bio
+ *
+ * Description:
+ * Generate and issue number of bios(REQ_OP_WRITE_SAME) with same page.
+ */
+static int __blkdev_issue_write_same(struct block_device *bdev, sector_t sector,
+ sector_t nr_sects, gfp_t gfp_mask, struct page *page,
+ struct bio **biop)
+{
+ struct request_queue *q = bdev_get_queue(bdev);
+ unsigned int max_write_same_sectors;
+ struct bio *bio = *biop;
+ sector_t bs_mask;
+
+ if (!q)
+ return -ENXIO;
+
+ if (bdev_read_only(bdev))
+ return -EPERM;
+
+ bs_mask = (bdev_logical_block_size(bdev) >> 9) - 1;
+ if ((sector | nr_sects) & bs_mask)
+ return -EINVAL;
+
+ if (!bdev_write_same(bdev))
+ return -EOPNOTSUPP;
+
+ /* Ensure that max_write_same_sectors doesn't overflow bi_size */
+ max_write_same_sectors = bio_allowed_max_sectors(q);
+
+ while (nr_sects) {
+ bio = blk_next_bio(bio, 1, gfp_mask);
+ bio->bi_iter.bi_sector = sector;
+ bio_set_dev(bio, bdev);
+ bio->bi_vcnt = 1;
+ bio->bi_io_vec->bv_page = page;
+ bio->bi_io_vec->bv_offset = 0;
+ bio->bi_io_vec->bv_len = bdev_logical_block_size(bdev);
+ bio_set_op_attrs(bio, REQ_OP_WRITE_SAME, 0);
+
+ if (nr_sects > max_write_same_sectors) {
+ bio->bi_iter.bi_size = max_write_same_sectors << 9;
+ nr_sects -= max_write_same_sectors;
+ sector += max_write_same_sectors;
+ } else {
+ bio->bi_iter.bi_size = nr_sects << 9;
+ nr_sects = 0;
+ }
+ cond_resched();
+ }
+
+ *biop = bio;
+ return 0;
+}
+
+/**
+ * blkdev_issue_write_same - queue a write same operation
+ * @bdev: target blockdev
+ * @sector: start sector
+ * @nr_sects: number of sectors to write
+ * @gfp_mask: memory allocation flags (for bio_alloc)
+ * @page: page containing data
+ *
+ * Description:
+ * Issue a write same request for the sectors in question.
+ */
+int blkdev_issue_write_same(struct block_device *bdev, sector_t sector,
+ sector_t nr_sects, gfp_t gfp_mask,
+ struct page *page)
+{
+ struct bio *bio = NULL;
+ struct blk_plug plug;
+ int ret;
+
+ blk_start_plug(&plug);
+ ret = __blkdev_issue_write_same(bdev, sector, nr_sects, gfp_mask, page,
+ &bio);
+ if (ret == 0 && bio) {
+ ret = submit_bio_wait(bio);
+ bio_put(bio);
+ }
+ blk_finish_plug(&plug);
+ return ret;
+}
+EXPORT_SYMBOL(blkdev_issue_write_same);
+
+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;
+ struct request_queue *q = bdev_get_queue(bdev);
+
+ if (!q)
+ return -ENXIO;
+
+ 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, 0, gfp_mask);
+ bio->bi_iter.bi_sector = sector;
+ bio_set_dev(bio, bdev);
+ bio->bi_opf = REQ_OP_WRITE_ZEROES;
+ 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_PAGES);
+}
+
+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 request_queue *q = bdev_get_queue(bdev);
+ struct bio *bio = *biop;
+ int bi_size = 0;
+ unsigned int sz;
+
+ if (!q)
+ return -ENXIO;
+
+ if (bdev_read_only(bdev))
+ return -EPERM;
+
+ while (nr_sects != 0) {
+ bio = blk_next_bio(bio, __blkdev_sectors_to_bio_pages(nr_sects),
+ gfp_mask);
+ bio->bi_iter.bi_sector = sector;
+ bio_set_dev(bio, bdev);
+ bio_set_op_attrs(bio, REQ_OP_WRITE, 0);
+
+ 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);