On Mon, Apr 24, 2023 at 8:22 AM Christoph Hellwig <hch@xxxxxx> wrote:
> All callers of generic_perform_write need to updated ki_pos, move it into
> common code.
We've actually got a similar situation with
iomap_file_buffered_write() and its callers. Would it make sense to
fix that up as well?
> Signed-off-by: Christoph Hellwig <hch@xxxxxx>
> ---
> fs/ceph/file.c | 2 --
> fs/ext4/file.c | 9 +++------
> fs/f2fs/file.c | 1 -
> fs/nfs/file.c | 1 -
> mm/filemap.c | 8 ++++----
> 5 files changed, 7 insertions(+), 14 deletions(-)
>
> diff --git a/fs/ceph/file.c b/fs/ceph/file.c
> index f4d8bf7dec88a8..feeb9882ef635a 100644
> --- a/fs/ceph/file.c
> +++ b/fs/ceph/file.c
> @@ -1894,8 +1894,6 @@ static ssize_t ceph_write_iter(struct kiocb *iocb, struct iov_iter *from)
> * can not run at the same time
> */
> written = generic_perform_write(iocb, from);
> - if (likely(written >= 0))
> - iocb->ki_pos = pos + written;
> ceph_end_io_write(inode);
> }
>
> diff --git a/fs/ext4/file.c b/fs/ext4/file.c
> index 0b8b4499e5ca18..1026acaf1235a0 100644
> --- a/fs/ext4/file.c
> +++ b/fs/ext4/file.c
> @@ -291,12 +291,9 @@ static ssize_t ext4_buffered_write_iter(struct kiocb *iocb,
>
> out:
> inode_unlock(inode);
> - if (likely(ret > 0)) {
> - iocb->ki_pos += ret;
> - ret = generic_write_sync(iocb, ret);
> - }
> -
> - return ret;
> + if (unlikely(ret <= 0))
> + return ret;
> + return generic_write_sync(iocb, ret);
> }
>
> static ssize_t ext4_handle_inode_extension(struct inode *inode, loff_t offset,
> diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c
> index f4ab23efcf85f8..5a9ae054b6da7d 100644
> --- a/fs/f2fs/file.c
> +++ b/fs/f2fs/file.c
> @@ -4511,7 +4511,6 @@ static ssize_t f2fs_buffered_write_iter(struct kiocb *iocb,
> current->backing_dev_info = NULL;
>
> if (ret > 0) {
> - iocb->ki_pos += ret;
> f2fs_update_iostat(F2FS_I_SB(inode), inode,
> APP_BUFFERED_IO, ret);
> }
> diff --git a/fs/nfs/file.c b/fs/nfs/file.c
> index 893625eacab9fa..abdae2b29369be 100644
> --- a/fs/nfs/file.c
> +++ b/fs/nfs/file.c
> @@ -666,7 +666,6 @@ ssize_t nfs_file_write(struct kiocb *iocb, struct iov_iter *from)
> goto out;
>
> written = result;
> - iocb->ki_pos += written;
> nfs_add_stats(inode, NFSIOS_NORMALWRITTENBYTES, written);
>
> if (mntflags & NFS_MOUNT_WRITE_EAGER) {
> diff --git a/mm/filemap.c b/mm/filemap.c
> index 2723104cc06a12..0110bde3708b3f 100644
> --- a/mm/filemap.c
> +++ b/mm/filemap.c
> @@ -3960,7 +3960,10 @@ ssize_t generic_perform_write(struct kiocb *iocb, struct iov_iter *i)
> balance_dirty_pages_ratelimited(mapping);
> } while (iov_iter_count(i));
>
> - return written ? written : status;
> + if (!written)
> + return status;
> + iocb->ki_pos += written;
Could be turned into:
iocb->ki_pos = pos;
> + return written;
> }
> EXPORT_SYMBOL(generic_perform_write);
>
> @@ -4039,7 +4042,6 @@ ssize_t __generic_file_write_iter(struct kiocb *iocb, struct iov_iter *from)
> endbyte = pos + status - 1;
> err = filemap_write_and_wait_range(mapping, pos, endbyte);
> if (err == 0) {
> - iocb->ki_pos = endbyte + 1;
> written += status;
> invalidate_mapping_pages(mapping,
> pos >> PAGE_SHIFT,
> @@ -4052,8 +4054,6 @@ ssize_t __generic_file_write_iter(struct kiocb *iocb, struct iov_iter *from)
> }
> } else {
> written = generic_perform_write(iocb, from);
> - if (likely(written > 0))
> - iocb->ki_pos += written;
> }
> out:
> current->backing_dev_info = NULL;
> --
> 2.39.2
>
Thanks,
Andreas
