Message ID | 20210121085906.322712-11-hch@lst.de (mailing list archive) |
---|---|
State | Superseded |
Headers | show |
Series | [01/11] xfs: factor out a xfs_ilock_iocb helper | expand |
On Thu, Jan 21, 2021 at 09:59:05AM +0100, Christoph Hellwig wrote: > Add a flag to signal an only pure overwrites are allowed. > > Signed-off-by: Christoph Hellwig <hch@lst.de> > --- > fs/iomap/direct-io.c | 7 +++++++ > include/linux/iomap.h | 8 ++++++++ > 2 files changed, 15 insertions(+) IOMAP_DIO_OVERWRITE_ONLY is a much better name compared to all the other alternatives that were suggested. :) > diff --git a/fs/iomap/direct-io.c b/fs/iomap/direct-io.c > index 947343730e2c93..65d32364345d22 100644 > --- a/fs/iomap/direct-io.c > +++ b/fs/iomap/direct-io.c > @@ -485,6 +485,13 @@ __iomap_dio_rw(struct kiocb *iocb, struct iov_iter *iter, > iomap_flags |= IOMAP_NOWAIT; > } > > + if (dio_flags & IOMAP_DIO_OVERWRITE_ONLY) { > + ret = -EAGAIN; > + if (pos >= dio->i_size || pos + count > dio->i_size) > + goto out_free_dio; > + iomap_flags |= IOMAP_OVERWRITE_ONLY; > + } > + > ret = filemap_write_and_wait_range(mapping, pos, end); > if (ret) > goto out_free_dio; > diff --git a/include/linux/iomap.h b/include/linux/iomap.h > index be4e1e1e01e801..cfa20afd7d5b87 100644 > --- a/include/linux/iomap.h > +++ b/include/linux/iomap.h > @@ -122,6 +122,7 @@ struct iomap_page_ops { > #define IOMAP_FAULT (1 << 3) /* mapping for page fault */ > #define IOMAP_DIRECT (1 << 4) /* direct I/O */ > #define IOMAP_NOWAIT (1 << 5) /* do not block */ > +#define IOMAP_OVERWRITE_ONLY (1 << 6) /* purely overwrites allowed */ Nit: s/purely/pure/ But otherwise good. Reviewed-by: Dave Chinner <dchinner@redhat.com>
On Thu, Jan 21, 2021 at 09:59:05AM +0100, Christoph Hellwig wrote: > Add a flag to signal an only pure overwrites are allowed. > > Signed-off-by: Christoph Hellwig <hch@lst.de> > --- Agreed that the explicit flag name is much more clear: Reviewed-by: Brian Foster <bfoster@redhat.com> > fs/iomap/direct-io.c | 7 +++++++ > include/linux/iomap.h | 8 ++++++++ > 2 files changed, 15 insertions(+) > > diff --git a/fs/iomap/direct-io.c b/fs/iomap/direct-io.c > index 947343730e2c93..65d32364345d22 100644 > --- a/fs/iomap/direct-io.c > +++ b/fs/iomap/direct-io.c > @@ -485,6 +485,13 @@ __iomap_dio_rw(struct kiocb *iocb, struct iov_iter *iter, > iomap_flags |= IOMAP_NOWAIT; > } > > + if (dio_flags & IOMAP_DIO_OVERWRITE_ONLY) { > + ret = -EAGAIN; > + if (pos >= dio->i_size || pos + count > dio->i_size) > + goto out_free_dio; > + iomap_flags |= IOMAP_OVERWRITE_ONLY; > + } > + > ret = filemap_write_and_wait_range(mapping, pos, end); > if (ret) > goto out_free_dio; > diff --git a/include/linux/iomap.h b/include/linux/iomap.h > index be4e1e1e01e801..cfa20afd7d5b87 100644 > --- a/include/linux/iomap.h > +++ b/include/linux/iomap.h > @@ -122,6 +122,7 @@ struct iomap_page_ops { > #define IOMAP_FAULT (1 << 3) /* mapping for page fault */ > #define IOMAP_DIRECT (1 << 4) /* direct I/O */ > #define IOMAP_NOWAIT (1 << 5) /* do not block */ > +#define IOMAP_OVERWRITE_ONLY (1 << 6) /* purely overwrites allowed */ > > struct iomap_ops { > /* > @@ -262,6 +263,13 @@ struct iomap_dio_ops { > */ > #define IOMAP_DIO_FORCE_WAIT (1 << 0) > > +/* > + * Do not allocate blocks or zero partial blocks, but instead fall back to > + * the caller by returning -EAGAIN. Used to optimize direct I/O writes that > + * are not aligned to the file system block size. > + */ > +#define IOMAP_DIO_OVERWRITE_ONLY (1 << 1) > + > ssize_t iomap_dio_rw(struct kiocb *iocb, struct iov_iter *iter, > const struct iomap_ops *ops, const struct iomap_dio_ops *dops, > unsigned int dio_flags); > -- > 2.29.2 >
On Thu, Jan 21, 2021 at 09:59:05AM +0100, Christoph Hellwig wrote: > Add a flag to signal an only pure overwrites are allowed. > > Signed-off-by: Christoph Hellwig <hch@lst.de> > --- > fs/iomap/direct-io.c | 7 +++++++ > include/linux/iomap.h | 8 ++++++++ > 2 files changed, 15 insertions(+) > > diff --git a/fs/iomap/direct-io.c b/fs/iomap/direct-io.c > index 947343730e2c93..65d32364345d22 100644 > --- a/fs/iomap/direct-io.c > +++ b/fs/iomap/direct-io.c > @@ -485,6 +485,13 @@ __iomap_dio_rw(struct kiocb *iocb, struct iov_iter *iter, > iomap_flags |= IOMAP_NOWAIT; > } > > + if (dio_flags & IOMAP_DIO_OVERWRITE_ONLY) { > + ret = -EAGAIN; > + if (pos >= dio->i_size || pos + count > dio->i_size) > + goto out_free_dio; > + iomap_flags |= IOMAP_OVERWRITE_ONLY; > + } > + > ret = filemap_write_and_wait_range(mapping, pos, end); > if (ret) > goto out_free_dio; > diff --git a/include/linux/iomap.h b/include/linux/iomap.h > index be4e1e1e01e801..cfa20afd7d5b87 100644 > --- a/include/linux/iomap.h > +++ b/include/linux/iomap.h > @@ -122,6 +122,7 @@ struct iomap_page_ops { > #define IOMAP_FAULT (1 << 3) /* mapping for page fault */ > #define IOMAP_DIRECT (1 << 4) /* direct I/O */ > #define IOMAP_NOWAIT (1 << 5) /* do not block */ > +#define IOMAP_OVERWRITE_ONLY (1 << 6) /* purely overwrites allowed */ "only pure overwrites allowed" ? With that fixed, Reviewed-by: Darrick J. Wong <djwong@kernel.org> --D > > struct iomap_ops { > /* > @@ -262,6 +263,13 @@ struct iomap_dio_ops { > */ > #define IOMAP_DIO_FORCE_WAIT (1 << 0) > > +/* > + * Do not allocate blocks or zero partial blocks, but instead fall back to > + * the caller by returning -EAGAIN. Used to optimize direct I/O writes that > + * are not aligned to the file system block size. > + */ > +#define IOMAP_DIO_OVERWRITE_ONLY (1 << 1) > + > ssize_t iomap_dio_rw(struct kiocb *iocb, struct iov_iter *iter, > const struct iomap_ops *ops, const struct iomap_dio_ops *dops, > unsigned int dio_flags); > -- > 2.29.2 >
diff --git a/fs/iomap/direct-io.c b/fs/iomap/direct-io.c index 947343730e2c93..65d32364345d22 100644 --- a/fs/iomap/direct-io.c +++ b/fs/iomap/direct-io.c @@ -485,6 +485,13 @@ __iomap_dio_rw(struct kiocb *iocb, struct iov_iter *iter, iomap_flags |= IOMAP_NOWAIT; } + if (dio_flags & IOMAP_DIO_OVERWRITE_ONLY) { + ret = -EAGAIN; + if (pos >= dio->i_size || pos + count > dio->i_size) + goto out_free_dio; + iomap_flags |= IOMAP_OVERWRITE_ONLY; + } + ret = filemap_write_and_wait_range(mapping, pos, end); if (ret) goto out_free_dio; diff --git a/include/linux/iomap.h b/include/linux/iomap.h index be4e1e1e01e801..cfa20afd7d5b87 100644 --- a/include/linux/iomap.h +++ b/include/linux/iomap.h @@ -122,6 +122,7 @@ struct iomap_page_ops { #define IOMAP_FAULT (1 << 3) /* mapping for page fault */ #define IOMAP_DIRECT (1 << 4) /* direct I/O */ #define IOMAP_NOWAIT (1 << 5) /* do not block */ +#define IOMAP_OVERWRITE_ONLY (1 << 6) /* purely overwrites allowed */ struct iomap_ops { /* @@ -262,6 +263,13 @@ struct iomap_dio_ops { */ #define IOMAP_DIO_FORCE_WAIT (1 << 0) +/* + * Do not allocate blocks or zero partial blocks, but instead fall back to + * the caller by returning -EAGAIN. Used to optimize direct I/O writes that + * are not aligned to the file system block size. + */ +#define IOMAP_DIO_OVERWRITE_ONLY (1 << 1) + ssize_t iomap_dio_rw(struct kiocb *iocb, struct iov_iter *iter, const struct iomap_ops *ops, const struct iomap_dio_ops *dops, unsigned int dio_flags);
Add a flag to signal an only pure overwrites are allowed. Signed-off-by: Christoph Hellwig <hch@lst.de> --- fs/iomap/direct-io.c | 7 +++++++ include/linux/iomap.h | 8 ++++++++ 2 files changed, 15 insertions(+)