Unverified Commit b4de0e9b authored by John Garry's avatar John Garry Committed by Christian Brauner
Browse files

iomap: Rename IOMAP_ATOMIC -> IOMAP_ATOMIC_HW 



In future xfs will support a SW-based atomic write, so rename
IOMAP_ATOMIC -> IOMAP_ATOMIC_HW to be clear which mode is being used.

Also relocate setting of IOMAP_ATOMIC_HW to the write path in
__iomap_dio_rw(), to be clear that this flag is only relevant to writes.

Reviewed-by: default avatar"Darrick J. Wong" <djwong@kernel.org>
Signed-off-by: default avatarJohn Garry <john.g.garry@oracle.com>
Link: https://lore.kernel.org/r/20250303171120.2837067-3-john.g.garry@oracle.com


Signed-off-by: default avatarChristian Brauner <brauner@kernel.org>
parent 1743d385

Documentation/filesystems/iomap/operations.rst

+2 −2
Original line number Diff line number Diff line
@@ -514,8 +514,8 @@ IOMAP_WRITE`` with any combination of the following enhancements: 
   if the mapping is unwritten and the filesystem cannot handle zeroing

   the unaligned regions without exposing stale contents.



 * ``IOMAP_ATOMIC``: This write is being issued with torn-write

   protection.

 * ``IOMAP_ATOMIC_HW``: This write is being issued with torn-write

   protection based on HW-offload support.

   Only a single bio can be created for the write, and the write must

   not be split into multiple I/O requests, i.e. flag REQ_ATOMIC must be

   set.

fs/ext4/inode.c

+1 −1
Original line number Diff line number Diff line
@@ -3467,7 +3467,7 @@ static inline bool ext4_want_directio_fallback(unsigned flags, ssize_t written) 
		return false;



	/* atomic writes are all-or-nothing */

	if (flags & IOMAP_ATOMIC)

	if (flags & IOMAP_ATOMIC_HW)

		return false;



	/* can only try again if we wrote nothing */

fs/iomap/direct-io.c

+9 −9
Original line number Diff line number Diff line
@@ -317,7 +317,7 @@ static int iomap_dio_zero(const struct iomap_iter *iter, struct iomap_dio *dio, 
 * clearing the WRITE_THROUGH flag in the dio request.

 */

static inline blk_opf_t iomap_dio_bio_opflags(struct iomap_dio *dio,

		const struct iomap *iomap, bool use_fua, bool atomic)

		const struct iomap *iomap, bool use_fua, bool atomic_hw)

{

	blk_opf_t opflags = REQ_SYNC | REQ_IDLE;
@@ -329,7 +329,7 @@ static inline blk_opf_t iomap_dio_bio_opflags(struct iomap_dio *dio, 
		opflags |= REQ_FUA;

	else

		dio->flags &= ~IOMAP_DIO_WRITE_THROUGH;

	if (atomic)

	if (atomic_hw)

		opflags |= REQ_ATOMIC;



	return opflags;
@@ -340,8 +340,8 @@ static int iomap_dio_bio_iter(struct iomap_iter *iter, struct iomap_dio *dio) 
	const struct iomap *iomap = &iter->iomap;

	struct inode *inode = iter->inode;

	unsigned int fs_block_size = i_blocksize(inode), pad;

	bool atomic_hw = iter->flags & IOMAP_ATOMIC_HW;

	const loff_t length = iomap_length(iter);

	bool atomic = iter->flags & IOMAP_ATOMIC;

	loff_t pos = iter->pos;

	blk_opf_t bio_opf;

	struct bio *bio;
@@ -351,7 +351,7 @@ static int iomap_dio_bio_iter(struct iomap_iter *iter, struct iomap_dio *dio) 
	u64 copied = 0;

	size_t orig_count;



	if (atomic && length != fs_block_size)

	if (atomic_hw && length != fs_block_size)

		return -EINVAL;



	if ((pos | length) & (bdev_logical_block_size(iomap->bdev) - 1) ||
@@ -428,7 +428,7 @@ static int iomap_dio_bio_iter(struct iomap_iter *iter, struct iomap_dio *dio) 
			goto out;

	}



	bio_opf = iomap_dio_bio_opflags(dio, iomap, use_fua, atomic);

	bio_opf = iomap_dio_bio_opflags(dio, iomap, use_fua, atomic_hw);



	nr_pages = bio_iov_vecs_to_alloc(dio->submit.iter, BIO_MAX_VECS);

	do {
@@ -461,7 +461,7 @@ static int iomap_dio_bio_iter(struct iomap_iter *iter, struct iomap_dio *dio) 
		}



		n = bio->bi_iter.bi_size;

		if (WARN_ON_ONCE(atomic && n != length)) {

		if (WARN_ON_ONCE(atomic_hw && n != length)) {

			/*

			 * This bio should have covered the complete length,

			 * which it doesn't, so error. We may need to zero out
@@ -652,9 +652,6 @@ __iomap_dio_rw(struct kiocb *iocb, struct iov_iter *iter, 
	if (iocb->ki_flags & IOCB_NOWAIT)

		iomi.flags |= IOMAP_NOWAIT;



	if (iocb->ki_flags & IOCB_ATOMIC)

		iomi.flags |= IOMAP_ATOMIC;



	if (iov_iter_rw(iter) == READ) {

		/* reads can always complete inline */

		dio->flags |= IOMAP_DIO_INLINE_COMP;
@@ -689,6 +686,9 @@ __iomap_dio_rw(struct kiocb *iocb, struct iov_iter *iter, 
			iomi.flags |= IOMAP_OVERWRITE_ONLY;

		}



		if (iocb->ki_flags & IOCB_ATOMIC)

			iomi.flags |= IOMAP_ATOMIC_HW;



		/* for data sync or sync, we need sync completion processing */

		if (iocb_is_dsync(iocb)) {

			dio->flags |= IOMAP_DIO_NEED_SYNC;

fs/iomap/trace.h

+1 −1
Original line number Diff line number Diff line
@@ -99,7 +99,7 @@ DEFINE_RANGE_EVENT(iomap_dio_rw_queued); 
	{ IOMAP_FAULT,		"FAULT" }, \

	{ IOMAP_DIRECT,		"DIRECT" }, \

	{ IOMAP_NOWAIT,		"NOWAIT" }, \

	{ IOMAP_ATOMIC,		"ATOMIC" }

	{ IOMAP_ATOMIC_HW,	"ATOMIC_HW" }



#define IOMAP_F_FLAGS_STRINGS \

	{ IOMAP_F_NEW,		"NEW" }, \

include/linux/iomap.h

+1 −1
Original line number Diff line number Diff line
@@ -189,7 +189,7 @@ struct iomap_folio_ops { 
#else

#define IOMAP_DAX		0

#endif /* CONFIG_FS_DAX */

#define IOMAP_ATOMIC		(1 << 9)

#define IOMAP_ATOMIC_HW		(1 << 9)

#define IOMAP_DONTCACHE		(1 << 10)



struct iomap_ops {