Re: [PATCH RESEND V12 1/8] fs: Generic function to convert iocb to rw flags

[Alessio Balsini]

On Mon, Jan 25, 2021 at 03:30:50PM +0000, Alessio Balsini wrote:
> OverlayFS implements its own function to translate iocb flags into rw
> flags, so that they can be passed into another vfs call.
> With commit ce71bfea207b4 ("fs: align IOCB_* flags with RWF_* flags")
> Jens created a 1:1 matching between the iocb flags and rw flags,
> simplifying the conversion.
> 
> Reduce the OverlayFS code by making the flag conversion function generic
> and reusable.
> 
> Signed-off-by: Alessio Balsini <balsini@xxxxxxxxxxx>
> ---
>  fs/overlayfs/file.c | 23 +++++------------------
>  include/linux/fs.h  |  5 +++++
>  2 files changed, 10 insertions(+), 18 deletions(-)
> 
> diff --git a/fs/overlayfs/file.c b/fs/overlayfs/file.c
> index bd9dd38347ae..56be2ffc5a14 100644
> --- a/fs/overlayfs/file.c
> +++ b/fs/overlayfs/file.c
> @@ -15,6 +15,8 @@
>  #include <linux/fs.h>
>  #include "overlayfs.h"
>  
> +#define OVL_IOCB_MASK (IOCB_DSYNC | IOCB_HIPRI | IOCB_NOWAIT | IOCB_SYNC)
> +
>  struct ovl_aio_req {
>  	struct kiocb iocb;
>  	struct kiocb *orig_iocb;
> @@ -236,22 +238,6 @@ static void ovl_file_accessed(struct file *file)
>  	touch_atime(&file->f_path);
>  }
>  
> -static rwf_t ovl_iocb_to_rwf(int ifl)
> -{
> -	rwf_t flags = 0;
> -
> -	if (ifl & IOCB_NOWAIT)
> -		flags |= RWF_NOWAIT;
> -	if (ifl & IOCB_HIPRI)
> -		flags |= RWF_HIPRI;
> -	if (ifl & IOCB_DSYNC)
> -		flags |= RWF_DSYNC;
> -	if (ifl & IOCB_SYNC)
> -		flags |= RWF_SYNC;
> -
> -	return flags;
> -}
> -
>  static void ovl_aio_cleanup_handler(struct ovl_aio_req *aio_req)
>  {
>  	struct kiocb *iocb = &aio_req->iocb;
> @@ -299,7 +285,8 @@ static ssize_t ovl_read_iter(struct kiocb *iocb, struct iov_iter *iter)
>  	old_cred = ovl_override_creds(file_inode(file)->i_sb);
>  	if (is_sync_kiocb(iocb)) {
>  		ret = vfs_iter_read(real.file, iter, &iocb->ki_pos,
> -				    ovl_iocb_to_rwf(iocb->ki_flags));
> +				    iocb_to_rw_flags(iocb->ki_flags,
> +						     OVL_IOCB_MASK));
>  	} else {
>  		struct ovl_aio_req *aio_req;
>  
> @@ -356,7 +343,7 @@ static ssize_t ovl_write_iter(struct kiocb *iocb, struct iov_iter *iter)
>  	if (is_sync_kiocb(iocb)) {
>  		file_start_write(real.file);
>  		ret = vfs_iter_write(real.file, iter, &iocb->ki_pos,
> -				     ovl_iocb_to_rwf(ifl));
> +				     iocb_to_rw_flags(ifl, OVL_IOCB_MASK));
>  		file_end_write(real.file);
>  		/* Update size */
>  		ovl_copyattr(ovl_inode_real(inode), inode);
> diff --git a/include/linux/fs.h b/include/linux/fs.h
> index fd47deea7c17..647c35423545 100644
> --- a/include/linux/fs.h
> +++ b/include/linux/fs.h
> @@ -3275,6 +3275,11 @@ static inline int kiocb_set_rw_flags(struct kiocb *ki, rwf_t flags)
>  	return 0;
>  }
>  
> +static inline rwf_t iocb_to_rw_flags(int ifl, int iocb_mask)
> +{
> +	return ifl & iocb_mask;
> +}
> +
>  static inline ino_t parent_ino(struct dentry *dentry)
>  {
>  	ino_t res;
> -- 
> 2.30.0.280.ga3ce27912f-goog
> 

For some reason lkml.org and lore.kernel.org are not showing this change
as part of the thread.
Let's see if replying to the email fixes the indexing.

Regards,
Alessio