On Wed, Mar 05, 2025 at 01:57:26PM +0100, Carlos Maiolino wrote:
> Hi Christian,
> On Mon, Mar 03, 2025 at 05:11:10PM +0000, John Garry wrote:
> > 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: "Darrick J. Wong" <djwong@xxxxxxxxxx>
> > Signed-off-by: John Garry <john.g.garry@xxxxxxxxxx>
>
> I pushed the patches in this series into this branch:
> git://git.kernel.org/pub/scm/fs/xfs/xfs-linux.git xfs-6.15-atomicwrites
>
> Do you plan to send the iomap patches in this series yourself or is it ok with
> you if they go through xfs tree?
Ok, so this will have merge conflicts with vfs-6.15.iomap. I put the
preliminary iomap patches of this series onto vfs-6.15.iomap.
Please simply pull vfs-6.15.iomap instead of vfs-6.15.shared.iomap.
Nothing changes for you as everything has been kept stable. There'll be
no merge conflicts for us afterwards.
Thanks for the ping!
>
> Cheers,
> Carlos
>
> > ---
> > Documentation/filesystems/iomap/operations.rst | 4 ++--
> > fs/ext4/inode.c | 2 +-
> > fs/iomap/direct-io.c | 18 +++++++++---------
> > fs/iomap/trace.h | 2 +-
> > include/linux/iomap.h | 2 +-
> > 5 files changed, 14 insertions(+), 14 deletions(-)
> >
> > diff --git a/Documentation/filesystems/iomap/operations.rst b/Documentation/filesystems/iomap/operations.rst
> > index d1535109587a..0b9d7be23bce 100644
> > --- a/Documentation/filesystems/iomap/operations.rst
> > +++ b/Documentation/filesystems/iomap/operations.rst
> > @@ -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.
> > diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
> > index 7c54ae5fcbd4..ba2f1e3db7c7 100644
> > --- a/fs/ext4/inode.c
> > +++ b/fs/ext4/inode.c
> > @@ -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 */
> > diff --git a/fs/iomap/direct-io.c b/fs/iomap/direct-io.c
> > index e1e32e2bb0bf..c696ce980796 100644
> > --- a/fs/iomap/direct-io.c
> > +++ b/fs/iomap/direct-io.c
> > @@ -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;
> > diff --git a/fs/iomap/trace.h b/fs/iomap/trace.h
> > index 9eab2c8ac3c5..69af89044ebd 100644
> > --- a/fs/iomap/trace.h
> > +++ b/fs/iomap/trace.h
> > @@ -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" }, \
> > diff --git a/include/linux/iomap.h b/include/linux/iomap.h
> > index ea29388b2fba..87cd7079aaf3 100644
> > --- a/include/linux/iomap.h
> > +++ b/include/linux/iomap.h
> > @@ -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 {
> > --
> > 2.31.1
> >
