Re: [PATCH v20 05/12] fs/read_write: Enable copy_file_range for block device.

[Hannes Reinecke]

On 5/20/24 12:20, Nitesh Shetty wrote:
> From: Anuj Gupta <anuj20.g@xxxxxxxxxxx>
>
> This is a prep patch. Allow copy_file_range to work for block devices.
> Relaxing generic_copy_file_checks allows us to reuse the existing infra,
> instead of adding a new user interface for block copy offload.
> Change generic_copy_file_checks to use ->f_mapping->host for both inode_in
> and inode_out. Allow block device in generic_file_rw_checks.
>
> Reviewed-by: Hannes Reinecke <hare@xxxxxxx>
> Signed-off-by: Anuj Gupta <anuj20.g@xxxxxxxxxxx>
> Signed-off-by: Nitesh Shetty <nj.shetty@xxxxxxxxxxx>
> ---
>   fs/read_write.c | 8 +++++---
>   1 file changed, 5 insertions(+), 3 deletions(-)
>
> diff --git a/fs/read_write.c b/fs/read_write.c
> index ef6339391351..31645ca5ed58 100644
> --- a/fs/read_write.c
> +++ b/fs/read_write.c
> @@ -1413,8 +1413,8 @@ static int generic_copy_file_checks(struct file *file_in, loff_t pos_in,
>   				    struct file *file_out, loff_t pos_out,
>   				    size_t *req_count, unsigned int flags)
>   {
> -	struct inode *inode_in = file_inode(file_in);
> -	struct inode *inode_out = file_inode(file_out);
> +	struct inode *inode_in = file_in->f_mapping->host;
> +	struct inode *inode_out = file_out->f_mapping->host;
>   	uint64_t count = *req_count;
>   	loff_t size_in;
>   	int ret;
> @@ -1726,7 +1726,9 @@ int generic_file_rw_checks(struct file *file_in, struct file *file_out)
>   	/* Don't copy dirs, pipes, sockets... */
>   	if (S_ISDIR(inode_in->i_mode) || S_ISDIR(inode_out->i_mode))
>   		return -EISDIR;
> -	if (!S_ISREG(inode_in->i_mode) || !S_ISREG(inode_out->i_mode))
> +	if (!S_ISREG(inode_in->i_mode) && !S_ISBLK(inode_in->i_mode))
> +		return -EINVAL;
> +	if ((inode_in->i_mode & S_IFMT) != (inode_out->i_mode & S_IFMT))
>   		return -EINVAL;
>   
>   	if (!(file_in->f_mode & FMODE_READ) ||

Reviewed-by: Hannes Reinecke <hare@xxxxxxx>

Cheers,

Hannes
--
Dr. Hannes Reinecke                  Kernel Storage Architect
hare@xxxxxxx                                +49 911 74053 688
SUSE Software Solutions GmbH, Frankenstr. 146, 90461 Nürnberg
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