On 5/19/23 17:35, Christoph Hellwig wrote:
> Move the assignment to current->backing_dev_info from the callers into
> generic_perform_write to reduce boiler plate code and reduce the scope
> to just around the page dirtying loop.
>
> Signed-off-by: Christoph Hellwig <[email protected]>
> ---
> fs/ceph/file.c | 4 ----
> fs/ext4/file.c | 3 ---
> fs/f2fs/file.c | 2 --
> fs/nfs/file.c | 5 +----
> mm/filemap.c | 2 ++
> 5 files changed, 3 insertions(+), 13 deletions(-)
>
> diff --git a/fs/ceph/file.c b/fs/ceph/file.c
> index feeb9882ef635a..767f4dfe7def64 100644
> --- a/fs/ceph/file.c
> +++ b/fs/ceph/file.c
> @@ -1791,9 +1791,6 @@ static ssize_t ceph_write_iter(struct kiocb *iocb, struct iov_iter *from)
> else
> ceph_start_io_write(inode);
>
> - /* We can write back this queue in page reclaim */
> - current->backing_dev_info = inode_to_bdi(inode);
> -
> if (iocb->ki_flags & IOCB_APPEND) {
> err = ceph_do_getattr(inode, CEPH_STAT_CAP_SIZE, false);
> if (err < 0)
> @@ -1938,7 +1935,6 @@ static ssize_t ceph_write_iter(struct kiocb *iocb, struct iov_iter *from)
> ceph_end_io_write(inode);
> out_unlocked:
> ceph_free_cap_flush(prealloc_cf);
> - current->backing_dev_info = NULL;
> return written ? written : err;
> }
>
> diff --git a/fs/ext4/file.c b/fs/ext4/file.c
> index 50824831d31def..3cb83a3e2e4a2a 100644
> --- a/fs/ext4/file.c
> +++ b/fs/ext4/file.c
> @@ -29,7 +29,6 @@
> #include <linux/pagevec.h>
> #include <linux/uio.h>
> #include <linux/mman.h>
> -#include <linux/backing-dev.h>
> #include "ext4.h"
> #include "ext4_jbd2.h"
> #include "xattr.h"
> @@ -285,9 +284,7 @@ static ssize_t ext4_buffered_write_iter(struct kiocb *iocb,
> if (ret <= 0)
> goto out;
>
> - current->backing_dev_info = inode_to_bdi(inode);
> ret = generic_perform_write(iocb, from);
> - current->backing_dev_info = NULL;
>
> out:
> inode_unlock(inode);
> diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c
> index 9e3855e43a7a63..7134fe8bd008cb 100644
> --- a/fs/f2fs/file.c
> +++ b/fs/f2fs/file.c
> @@ -4517,9 +4517,7 @@ static ssize_t f2fs_buffered_write_iter(struct kiocb *iocb,
> if (iocb->ki_flags & IOCB_NOWAIT)
> return -EOPNOTSUPP;
>
> - current->backing_dev_info = inode_to_bdi(inode);
> ret = generic_perform_write(iocb, from);
> - current->backing_dev_info = NULL;
>
> if (ret > 0) {
> f2fs_update_iostat(F2FS_I_SB(inode), inode,
> diff --git a/fs/nfs/file.c b/fs/nfs/file.c
> index 3cc87ae8473356..e8bb4c48a3210a 100644
> --- a/fs/nfs/file.c
> +++ b/fs/nfs/file.c
> @@ -648,11 +648,8 @@ ssize_t nfs_file_write(struct kiocb *iocb, struct iov_iter *from)
> since = filemap_sample_wb_err(file->f_mapping);
> nfs_start_io_write(inode);
> result = generic_write_checks(iocb, from);
> - if (result > 0) {
> - current->backing_dev_info = inode_to_bdi(inode);
> + if (result > 0)
> result = generic_perform_write(iocb, from);
> - current->backing_dev_info = NULL;
> - }
> nfs_end_io_write(inode);
> if (result <= 0)
> goto out;
> diff --git a/mm/filemap.c b/mm/filemap.c
> index 4d0ec2fa1c7070..bf693ad1da1ece 100644
> --- a/mm/filemap.c
> +++ b/mm/filemap.c
> @@ -3892,6 +3892,7 @@ ssize_t generic_perform_write(struct kiocb *iocb, struct iov_iter *i)
> long status = 0;
> ssize_t written = 0;
>
> + current->backing_dev_info = inode_to_bdi(mapping->host);
> do {
> struct page *page;
> unsigned long offset; /* Offset into pagecache page */
> @@ -3956,6 +3957,7 @@ ssize_t generic_perform_write(struct kiocb *iocb, struct iov_iter *i)
>
> balance_dirty_pages_ratelimited(mapping);
> } while (iov_iter_count(i));
> + current->backing_dev_info = NULL;
>
> if (!written)
> return status;
LGTM.
Reviewed-by: Xiubo Li <[email protected]>
Thanks
- Xiubo