diff options
| author | John Garry <john.g.garry@oracle.com> | 2024-06-20 12:53:56 +0000 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2024-06-20 15:19:17 -0600 |
| commit | caf336f81b3a3ca744e335972e86ec7244512d4a (patch) | |
| tree | dc5bf0641a35c57fd39f279f1d8343dee3ce26ef /block | |
| parent | 9abcfbd235f59fb5b6379e5bc0231dad831ebace (diff) | |
block: Add fops atomic write support
Support atomic writes by submitting a single BIO with the REQ_ATOMIC set.
It must be ensured that the atomic write adheres to its rules, like
naturally aligned offset, so call blkdev_dio_invalid() ->
blkdev_atomic_write_valid() [with renaming blkdev_dio_unaligned() to
blkdev_dio_invalid()] for this purpose. The BIO submission path currently
checks for atomic writes which are too large, so no need to check here.
In blkdev_direct_IO(), if the nr_pages exceeds BIO_MAX_VECS, then we cannot
produce a single BIO, so error in this case.
Finally set FMODE_CAN_ATOMIC_WRITE when the bdev can support atomic writes
and the associated file flag is for O_DIRECT.
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: John Garry <john.g.garry@oracle.com>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Acked-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Link: https://lore.kernel.org/r/20240620125359.2684798-8-john.g.garry@oracle.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'block')
| -rw-r--r-- | block/fops.c | 20 |
1 files changed, 17 insertions, 3 deletions
diff --git a/block/fops.c b/block/fops.c index 376265935714..be36c9fbd500 100644 --- a/block/fops.c +++ b/block/fops.c @@ -34,9 +34,12 @@ static blk_opf_t dio_bio_write_op(struct kiocb *iocb) return opf; } -static bool blkdev_dio_unaligned(struct block_device *bdev, loff_t pos, - struct iov_iter *iter) +static bool blkdev_dio_invalid(struct block_device *bdev, loff_t pos, + struct iov_iter *iter, bool is_atomic) { + if (is_atomic && !generic_atomic_write_valid(iter, pos)) + return true; + return pos & (bdev_logical_block_size(bdev) - 1) || !bdev_iter_is_aligned(bdev, iter); } @@ -72,6 +75,8 @@ static ssize_t __blkdev_direct_IO_simple(struct kiocb *iocb, bio.bi_iter.bi_sector = pos >> SECTOR_SHIFT; bio.bi_write_hint = file_inode(iocb->ki_filp)->i_write_hint; bio.bi_ioprio = iocb->ki_ioprio; + if (iocb->ki_flags & IOCB_ATOMIC) + bio.bi_opf |= REQ_ATOMIC; ret = bio_iov_iter_get_pages(&bio, iter); if (unlikely(ret)) @@ -343,6 +348,9 @@ static ssize_t __blkdev_direct_IO_async(struct kiocb *iocb, task_io_account_write(bio->bi_iter.bi_size); } + if (iocb->ki_flags & IOCB_ATOMIC) + bio->bi_opf |= REQ_ATOMIC; + if (iocb->ki_flags & IOCB_NOWAIT) bio->bi_opf |= REQ_NOWAIT; @@ -359,12 +367,13 @@ static ssize_t __blkdev_direct_IO_async(struct kiocb *iocb, static ssize_t blkdev_direct_IO(struct kiocb *iocb, struct iov_iter *iter) { struct block_device *bdev = I_BDEV(iocb->ki_filp->f_mapping->host); + bool is_atomic = iocb->ki_flags & IOCB_ATOMIC; unsigned int nr_pages; if (!iov_iter_count(iter)) return 0; - if (blkdev_dio_unaligned(bdev, iocb->ki_pos, iter)) + if (blkdev_dio_invalid(bdev, iocb->ki_pos, iter, is_atomic)) return -EINVAL; nr_pages = bio_iov_vecs_to_alloc(iter, BIO_MAX_VECS + 1); @@ -373,6 +382,8 @@ static ssize_t blkdev_direct_IO(struct kiocb *iocb, struct iov_iter *iter) return __blkdev_direct_IO_simple(iocb, iter, bdev, nr_pages); return __blkdev_direct_IO_async(iocb, iter, bdev, nr_pages); + } else if (is_atomic) { + return -EINVAL; } return __blkdev_direct_IO(iocb, iter, bdev, bio_max_segs(nr_pages)); } @@ -612,6 +623,9 @@ static int blkdev_open(struct inode *inode, struct file *filp) if (!bdev) return -ENXIO; + if (bdev_can_atomic_write(bdev) && filp->f_flags & O_DIRECT) + filp->f_mode |= FMODE_CAN_ATOMIC_WRITE; + ret = bdev_open(bdev, mode, filp->private_data, NULL, filp); if (ret) blkdev_put_no_open(bdev); |