{
struct request_queue *q = bdev_get_queue(bdev);
struct bio *bio = *biop;
- unsigned int granularity;
unsigned int op;
- int alignment;
sector_t bs_mask;
if (!q)
if ((sector | nr_sects) & bs_mask)
return -EINVAL;
- /* Zero-sector (unknown) and one-sector granularities are the same. */
- granularity = max(q->limits.discard_granularity >> 9, 1U);
- alignment = (bdev_discard_alignment(bdev) >> 9) % granularity;
-
while (nr_sects) {
- unsigned int req_sects;
- sector_t end_sect, tmp;
+ unsigned int req_sects = nr_sects;
+ sector_t end_sect;
- /* Make sure bi_size doesn't overflow */
- req_sects = min_t(sector_t, nr_sects, UINT_MAX >> 9);
+ req_sects = min(req_sects, bio_allowed_max_sectors(q));
+ if (!req_sects)
+ goto fail;
- /**
- * If splitting a request, and the next starting sector would be
- * misaligned, stop the discard at the previous aligned sector.
- */
end_sect = sector + req_sects;
- tmp = end_sect;
- if (req_sects < nr_sects &&
- sector_div(tmp, granularity) != alignment) {
- end_sect = end_sect - alignment;
- sector_div(end_sect, granularity);
- end_sect = end_sect * granularity + alignment;
- req_sects = end_sect - sector;
- }
bio = next_bio(bio, 0, gfp_mask);
bio->bi_iter.bi_sector = sector;
*biop = bio;
return 0;
+
+fail:
+ if (bio) {
+ submit_bio_wait(bio);
+ bio_put(bio);
+ }
+ *biop = NULL;
+ return -EOPNOTSUPP;
}
EXPORT_SYMBOL(__blkdev_issue_discard);
return -EOPNOTSUPP;
/* Ensure that max_write_same_sectors doesn't overflow bi_size */
- max_write_same_sectors = UINT_MAX >> 9;
+ max_write_same_sectors = bio_allowed_max_sectors(q);
while (nr_sects) {
bio = next_bio(bio, 1, gfp_mask);
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;
+
+ while (nr_sects != 0) {
+ bio = 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
* Zero-fill a block range, either using hardware offload or by explicitly
* writing zeroes to the device.
*
- * Note that this function may fail with -EOPNOTSUPP if the driver signals
- * zeroing offload support, but the device fails to process the command (for
- * some devices there is no non-destructive way to verify whether this
- * operation is actually supported). In this case the caller should call
- * retry the call to blkdev_issue_zeroout() and the fallback path will be used.
- *
* If a device is using logical block provisioning, the underlying space will
* not be released if %flags contains BLKDEV_ZERO_NOUNMAP.
*
unsigned flags)
{
int ret;
- int bi_size = 0;
- struct bio *bio = *biop;
- unsigned int sz;
sector_t bs_mask;
bs_mask = (bdev_logical_block_size(bdev) >> 9) - 1;
ret = __blkdev_issue_write_zeroes(bdev, sector, nr_sects, gfp_mask,
biop, flags);
if (ret != -EOPNOTSUPP || (flags & BLKDEV_ZERO_NOFALLBACK))
- goto out;
-
- ret = 0;
- while (nr_sects != 0) {
- bio = 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();
- }
+ return ret;
- *biop = bio;
-out:
- return ret;
+ return __blkdev_issue_zero_pages(bdev, sector, nr_sects, gfp_mask,
+ biop);
}
EXPORT_SYMBOL(__blkdev_issue_zeroout);
int blkdev_issue_zeroout(struct block_device *bdev, sector_t sector,
sector_t nr_sects, gfp_t gfp_mask, unsigned flags)
{
- int ret;
- struct bio *bio = NULL;
+ 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);
- ret = __blkdev_issue_zeroout(bdev, sector, nr_sects, gfp_mask,
- &bio, flags);
+ 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;
}
projects / mirror_ubuntu-bionic-kernel.git / blobdiff