[Devel] [PATCH VZ9] fs/fuse kio: Add kRPC versioning support

[Alexey Kuznetsov]

Ack

On Mon, Oct 7, 2024 at 11:11 PM Liu Kui <kui.liu at virtuozzo.com> wrote:
>
> Replace the module parameter 'pcs_krpc_support' with 'pcs_krpc_version'
> for better kRPC version management. Older userspace client would be able
> to detect version mismatch with absence of 'pcs_krpc_support', while
> newer userspace client will check against 'pcs_krpc_version'.
>
> Relates to
> https://virtuozzo.atlassian.net/browse/VSTOR-90183
>
> Signed-off-by: Liu Kui <kui.liu at virtuozzo.com>
> ---
>  fs/fuse/kio/pcs/pcs_fuse_kdirect.c | 6 +++---
>  fs/fuse/kio/pcs/pcs_krpc.c         | 3 +++
>  fs/fuse/kio/pcs/pcs_krpc_prot.h    | 8 +++++++-
>  3 files changed, 13 insertions(+), 4 deletions(-)
>
> diff --git a/fs/fuse/kio/pcs/pcs_fuse_kdirect.c b/fs/fuse/kio/pcs/pcs_fuse_kdirect.c
> index a0452bad1fd1..2bab4481844a 100644
> --- a/fs/fuse/kio/pcs/pcs_fuse_kdirect.c
> +++ b/fs/fuse/kio/pcs/pcs_fuse_kdirect.c
> @@ -81,9 +81,9 @@ unsigned int cpu_worker_flags = 1;
>  module_param(cpu_worker_flags, uint, 0444);
>  MODULE_PARM_DESC(cpu_worker_flags, "Set cpu worker flags");
>
> -bool pcs_krpc_support = true;
> -module_param(pcs_krpc_support, bool, 0444);
> -MODULE_PARM_DESC(pcs_krpc_support, "krpc support");
> +unsigned int pcs_krpc_version;
> +module_param(pcs_krpc_version, uint, 0444);
> +MODULE_PARM_DESC(pcs_krpc_version, "krpc version");
>
>  #define sel_wq_flags(f) ((((f) & 1) ? WQ_CPU_INTENSIVE : 0) | (((f) & 2) ? WQ_UNBOUND : 0))
>
> diff --git a/fs/fuse/kio/pcs/pcs_krpc.c b/fs/fuse/kio/pcs/pcs_krpc.c
> index 8f62f12782e5..4f3c988f1f3c 100644
> --- a/fs/fuse/kio/pcs/pcs_krpc.c
> +++ b/fs/fuse/kio/pcs/pcs_krpc.c
> @@ -17,6 +17,8 @@
>  #include "pcs_req.h"
>  #include "pcs_krpc.h"
>
> +extern unsigned int pcs_krpc_version;
> +
>  struct kmem_cache *krpc_req_cachep;
>
>  static int krpc_completion_post(struct pcs_krpc *krpc, struct krpc_completion *comp)
> @@ -913,6 +915,7 @@ int __init pcs_krpc_init(void)
>         if (!krpc_req_cachep)
>                 return -ENOMEM;
>
> +       pcs_krpc_version = PCS_KRPC_VERSION;
>         return 0;
>  }
>
> diff --git a/fs/fuse/kio/pcs/pcs_krpc_prot.h b/fs/fuse/kio/pcs/pcs_krpc_prot.h
> index 2729520a7cd0..81caa1d53669 100644
> --- a/fs/fuse/kio/pcs/pcs_krpc_prot.h
> +++ b/fs/fuse/kio/pcs/pcs_krpc_prot.h
> @@ -1,9 +1,15 @@
>  #ifndef _PCS_KRPC_PROT_H_
>  #define _PCS_KRPC_PROT_H_
>  #include <linux/ioctl.h>
> -
>  #include "pcs_prot_types.h"
>
> +/*
> + * kRPC version:
> + * v1: Initial krpc support
> + * v2: Support zerocopy read
> + */
> +#define PCS_KRPC_VERSION 2
> +
>  /* Device ioctls: */
>  #define PCS_KRPC_IOC_MAGIC  255
>
> --
> 2.39.5 (Apple Git-154)