On Oct 30, 2018, at 7:18 AM, Carlos Maiolino <cmaiolino@redhat.com> wrote:
> 
> Now that fiemap methods are updated to work based on the new fiemap_ctx
> structure, update the code to use the new callback.
> The current fiemap_fill_next_extent will be used for user calls of
> ->fiemap methods, as its done today, but passed in as a callback to
> fiemap_ctx. So, rename it to ifemap_fill_usr_extent().

Minor typo here s/ifemap/fiemap/

Couldn't this series have (mostly?) been achieved by just adding the
callback to fiemap_extent_info and using that everywhere?

Cheers, Andreas

> The 'new' fiemap_fill_next_extent() will now be just a helper to call
> fiemap_ctx callback.
> 
> Signed-off-by: Carlos Maiolino <cmaiolino@redhat.com>
> ---
> fs/ioctl.c         | 42 +++++++++++++++++++++++++-----------------
> include/linux/fs.h |  2 +-
> 2 files changed, 26 insertions(+), 18 deletions(-)
> 
> diff --git a/fs/ioctl.c b/fs/ioctl.c
> index 27f79b29cb07..85a7aec40e3d 100644
> --- a/fs/ioctl.c
> +++ b/fs/ioctl.c
> @@ -68,25 +68,10 @@ static int ioctl_fibmap(struct file *filp, int __user *p)
> 	return put_user(res, p);
> }
> 
> -/**
> - * fiemap_fill_next_extent - Fiemap helper function
> - * @fieinfo:	Fiemap context passed into ->fiemap
> - * @logical:	Extent logical start offset, in bytes
> - * @phys:	Extent physical start offset, in bytes
> - * @len:	Extent length, in bytes
> - * @flags:	FIEMAP_EXTENT flags that describe this extent
> - *
> - * Called from file system ->fiemap callback. Will populate extent
> - * info as passed in via arguments and copy to user memory. On
> - * success, extent count on fieinfo is incremented.
> - *
> - * Returns 0 on success, -errno on error, 1 if this was the last
> - * extent that will fit in user array.
> - */
> #define SET_UNKNOWN_FLAGS	(FIEMAP_EXTENT_DELALLOC)
> #define SET_NO_UNMOUNTED_IO_FLAGS	(FIEMAP_EXTENT_DATA_ENCRYPTED)
> #define SET_NOT_ALIGNED_FLAGS	(FIEMAP_EXTENT_DATA_TAIL|FIEMAP_EXTENT_DATA_INLINE)
> -int fiemap_fill_next_extent(struct fiemap_ctx *f_ctx, u64 logical,
> +int fiemap_fill_usr_extent(struct fiemap_ctx *f_ctx, u64 logical,
> 			    u64 phys, u64 len, u32 flags)
> {
> 	struct fiemap_extent_info *fieinfo = f_ctx->fc_data;
> @@ -124,8 +109,29 @@ int fiemap_fill_next_extent(struct fiemap_ctx *f_ctx, u64 logical,
> 		return 1;
> 	return (flags & FIEMAP_EXTENT_LAST) ? 1 : 0;
> }
> -EXPORT_SYMBOL(fiemap_fill_next_extent);
> 
> +/**
> + * fiemap_fill_next_extent - Fiemap helper function
> + * @fieinfo:	Fiemap context passed into ->fiemap
> + * @logical:	Extent logical start offset, in bytes
> + * @phys:	Extent physical start offset, in bytes
> + * @len:	Extent length, in bytes
> + * @flags:	FIEMAP_EXTENT flags that describe this extent
> + *
> + * Called from file system ->fiemap callback. Will populate extent
> + * info as passed in via arguments and copy to user memory. On
> + * success, extent count on fieinfo is incremented.
> + *
> + * Returns 0 on success, -errno on error, 1 if this was the last
> + * extent that will fit in user array.
> + */
> +
> +int fiemap_fill_next_extent(struct fiemap_ctx *f_ctx, u64 logical,
> +			    u64 phys, u64 len, u32 flags)
> +{
> +	return f_ctx->fc_cb(f_ctx, logical, phys, len, flags);
> +}
> +EXPORT_SYMBOL(fiemap_fill_next_extent);
> /**
>  * fiemap_check_flags - check validity of requested flags for fiemap
>  * @fieinfo:	Fiemap context passed into ->fiemap
> @@ -208,6 +214,8 @@ static int ioctl_fiemap(struct file *filp, unsigned long arg)
> 	f_ctx.fc_start = fiemap.fm_start;
> 	f_ctx.fc_len = len;
> 
> +	f_ctx.fc_cb = fiemap_fill_usr_extent;
> +
> 	if (fiemap.fm_extent_count != 0 &&
> 	    !access_ok(VERIFY_WRITE, fieinfo.fi_extents_start,
> 		       fieinfo.fi_extents_max * sizeof(struct fiemap_extent)))
> diff --git a/include/linux/fs.h b/include/linux/fs.h
> index 945cfb3e06e4..9a538bc0dac2 100644
> --- a/include/linux/fs.h
> +++ b/include/linux/fs.h
> @@ -1704,7 +1704,7 @@ typedef int (*fiemap_fill_cb)(struct fiemap_ctx *f_ctx, u64 logical,
> struct fiemap_ctx {
> 	unsigned int fc_flags;	/* Flags as passed from user */
> 	void *fc_data;
> -	fiemap_fill_cb fc_cb; /* Unused by now */
> +	fiemap_fill_cb fc_cb;
> 	u64 fc_start;
> 	u64 fc_len;
> };
> --
> 2.17.1
> 


Cheers, Andreas