Re: [PATCH v7 1/4] misc: fastrpc: Move fdlist to invoke context structure

[Srinivas Kandagatla <srini@kernel.org>]

On 4/2/26 5:49 AM, Ekansh Gupta wrote:
> The fdlist is currently part of the meta buffer which is set during
> fastrpc_get_args(), this fdlist is getting recalculated during
> fastrpc_put_args().
> 
> Move fdlist to the invoke context structure to improve maintainability
> and reduce redundancy. This centralizes its handling and simplifies
> meta buffer preparation and reading logic.
> 
> Signed-off-by: Ekansh Gupta <ekansh.gupta@oss.qualcomm.com>
> ---
>  drivers/misc/fastrpc.c | 13 ++++---------
>  1 file changed, 4 insertions(+), 9 deletions(-)
> 
> diff --git a/drivers/misc/fastrpc.c b/drivers/misc/fastrpc.c
> index 47356a5d5804..11f4ae749e51 100644
> --- a/drivers/misc/fastrpc.c
> +++ b/drivers/misc/fastrpc.c
> @@ -233,6 +233,7 @@ struct fastrpc_invoke_ctx {
>  	int pid;
>  	int client_id;
>  	u32 sc;
> +	u64 *fdlist;
>  	u32 *crc;
>  	u64 ctxid;
>  	u64 msg_sz;
> @@ -1016,6 +1017,7 @@ static int fastrpc_get_args(u32 kernel, struct fastrpc_invoke_ctx *ctx)
>  	rpra = ctx->buf->virt;
>  	list = fastrpc_invoke_buf_start(rpra, ctx->nscalars);
>  	pages = fastrpc_phy_page_start(list, ctx->nscalars);
> +	ctx->fdlist = (u64 *)(pages + ctx->nscalars);
>  	args = (uintptr_t)ctx->buf->virt + metalen;
>  	rlen = pkt_size - metalen;
>  	ctx->rpra = rpra;
> @@ -1118,18 +1120,11 @@ static int fastrpc_put_args(struct fastrpc_invoke_ctx *ctx,
>  	union fastrpc_remote_arg *rpra = ctx->rpra;
>  	struct fastrpc_user *fl = ctx->fl;
>  	struct fastrpc_map *mmap = NULL;
> -	struct fastrpc_invoke_buf *list;
> -	struct fastrpc_phy_page *pages;
> -	u64 *fdlist;
> -	int i, inbufs, outbufs, handles;
> +	u64 *fdlist = ctx->fdlist;

fdlist is available after input , output buffers and handles.

why this is now changed to nscalars?

--srini
> +	int i, inbufs;
>  	int ret = 0;
>  
>  	inbufs = REMOTE_SCALARS_INBUFS(ctx->sc);
> -	outbufs = REMOTE_SCALARS_OUTBUFS(ctx->sc);
> -	handles = REMOTE_SCALARS_INHANDLES(ctx->sc) + REMOTE_SCALARS_OUTHANDLES(ctx->sc);
> -	list = fastrpc_invoke_buf_start(rpra, ctx->nscalars);
> -	pages = fastrpc_phy_page_start(list, ctx->nscalars);
> -	fdlist = (uint64_t *)(pages + inbufs + outbufs + handles);
>  
>  	for (i = inbufs; i < ctx->nbufs; ++i) {
>  		if (!ctx->maps[i]) {