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See http://www.infradead.org/rpr.html X-Rspamd-Server: rspam06 X-Rspamd-Queue-Id: A2C71A0018 X-Stat-Signature: qcgtkj6yo1x7xcxd7e11pm1is9k1cr3f X-Rspam-User: X-HE-Tag: 1725955268-173047 X-HE-Meta: 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 EX8J5F+B 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 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: > + sector_t sector = start >> SECTOR_SHIFT; > + sector_t nr_sects = len >> SECTOR_SHIFT; > + struct bio *prev = NULL, *bio; > + int err; > + > + if (!bdev_max_discard_sectors(bdev)) > + return -EOPNOTSUPP; > + > + if (!(file_to_blk_mode(cmd->file) & BLK_OPEN_WRITE)) > + return -EBADF; > + if (bdev_read_only(bdev)) > + return -EPERM; > + err = blk_validate_byte_range(bdev, start, len); > + if (err) > + return err; Based on the above this function is misnamed, as it validates sector_t range and not a byte range. > + if (nowait && nr_sects > bio_discard_limit(bdev, sector)) > + return -EAGAIN; > + > + err = filemap_invalidate_pages(bdev->bd_mapping, start, > + start + len - 1, nowait); > + if (err) > + return err; > + > + while ((bio = blk_alloc_discard_bio(bdev, §or, &nr_sects, gfp))) { > + if (nowait) > + bio->bi_opf |= REQ_NOWAIT; > + prev = bio_chain_and_submit(prev, bio); > + } > + if (!prev) > + return -EAGAIN; If a user changes the max_discard value between the check above and the loop here this is racy. > +sector_t bio_discard_limit(struct block_device *bdev, sector_t sector); And to be honest, I'd really prefer to not have bio_discard_limit exposed. Certainly not outside a header private to block/. > + > #endif /* __LINUX_BIO_H */ > diff --git a/include/uapi/linux/fs.h b/include/uapi/linux/fs.h > index 753971770733..7ea41ca97158 100644 > --- a/include/uapi/linux/fs.h > +++ b/include/uapi/linux/fs.h > @@ -208,6 +208,8 @@ struct fsxattr { > * (see uapi/linux/blkzoned.h) > */ > > +#define BLOCK_URING_CMD_DISCARD _IO(0x12,137) Whitespace after the comma please. Also why start at 137? A comment would generally be pretty useful as well. Also can we have a include/uapi/linux/blkdev.h for this instead of bloating fs.h that gets included just about everywhere?