On 11/22/2024 3:51 AM, Dmitry Baryshkov wrote:
> On Thu, Nov 21, 2024 at 02:17:12PM +0530, Ekansh Gupta wrote:
>> Memory intensive applications(which requires more tha 4GB) that wants
>> to offload tasks to DSP might have to split the tasks to multiple
>> user PD to make the resources available.
>>
>> For every call to DSP, fastrpc driver passes the process tgid which
>> works as an identifier for the DSP to enqueue the tasks to specific PD.
>> With current design, if any process opens device node more than once
>> and makes PD init request, same tgid will be passed to DSP which will
>> be considered a bad request and this will result in failure as the same
>> identifier cannot be used for multiple DSP PD.
>>
>> Assign and pass a client ID to DSP which would be assigned during device
>> open and will be dependent on the index of session allocated for the PD.
>> This will allow the same process to open the device more than once and
>> spawn multiple dynamic PD for ease of processing.
>>
>> Signed-off-by: Ekansh Gupta <quic_ekang...@quicinc.com>
>> ---
>> drivers/misc/fastrpc.c | 30 ++++++++++++++++--------------
>> 1 file changed, 16 insertions(+), 14 deletions(-)
>>
>> diff --git a/drivers/misc/fastrpc.c b/drivers/misc/fastrpc.c
>> index 74181b8c386b..08f223c95c33 100644
>> --- a/drivers/misc/fastrpc.c
>> +++ b/drivers/misc/fastrpc.c
>> @@ -39,6 +39,7 @@
>> #define FASTRPC_INIT_HANDLE 1
>> #define FASTRPC_DSP_UTILITIES_HANDLE 2
>> #define FASTRPC_CTXID_MASK (0xFF0)
>> +#define FASTRPC_CLIENTID_MASK GENMASK(4, 4)
> GENMASK(4,4) is just BIT(4), isn't it?
>
>> #define INIT_FILELEN_MAX (2 * 1024 * 1024)
>> #define INIT_FILE_NAMELEN_MAX (128)
>> #define FASTRPC_DEVICE_NAME "fastrpc"
>> @@ -299,7 +300,7 @@ struct fastrpc_user {
>> struct fastrpc_session_ctx *sctx;
>> struct fastrpc_buf *init_mem;
>>
>> - int tgid;
>> + int client_id;
>> int pd;
>> bool is_secure_dev;
>> /* Lock for lists */
>> @@ -614,7 +615,7 @@ static struct fastrpc_invoke_ctx *fastrpc_context_alloc(
>> ctx->sc = sc;
>> ctx->retval = -1;
>> ctx->pid = current->pid;
>> - ctx->tgid = user->tgid;
>> + ctx->tgid = user->client_id;
>> ctx->cctx = cctx;
>> init_completion(&ctx->work);
>> INIT_WORK(&ctx->put_work, fastrpc_context_put_wq);
>> @@ -1115,7 +1116,7 @@ static int fastrpc_invoke_send(struct
>> fastrpc_session_ctx *sctx,
>> int ret;
>>
>> cctx = fl->cctx;
>> - msg->pid = fl->tgid;
>> + msg->pid = fl->client_id;
>> msg->tid = current->pid;
>>
>> if (kernel)
>> @@ -1293,7 +1294,7 @@ static int fastrpc_init_create_static_process(struct
>> fastrpc_user *fl,
>> }
>> }
>>
>> - inbuf.pgid = fl->tgid;
>> + inbuf.pgid = fl->client_id;
>> inbuf.namelen = init.namelen;
>> inbuf.pageslen = 0;
>> fl->pd = USER_PD;
>> @@ -1395,7 +1396,7 @@ static int fastrpc_init_create_process(struct
>> fastrpc_user *fl,
>> goto err;
>> }
>>
>> - inbuf.pgid = fl->tgid;
>> + inbuf.pgid = fl->client_id;
>> inbuf.namelen = strlen(current->comm) + 1;
>> inbuf.filelen = init.filelen;
>> inbuf.pageslen = 1;
>> @@ -1469,8 +1470,9 @@ static int fastrpc_init_create_process(struct
>> fastrpc_user *fl,
>> }
>>
>> static struct fastrpc_session_ctx *fastrpc_session_alloc(
>> - struct fastrpc_channel_ctx *cctx)
>> + struct fastrpc_user *fl)
>> {
>> + struct fastrpc_channel_ctx *cctx = fl->cctx;
>> struct fastrpc_session_ctx *session = NULL;
>> unsigned long flags;
>> int i;
>> @@ -1480,6 +1482,7 @@ static struct fastrpc_session_ctx
>> *fastrpc_session_alloc(
>> if (!cctx->session[i].used && cctx->session[i].valid) {
>> cctx->session[i].used = true;
>> session = &cctx->session[i];
>> + fl->client_id = FASTRPC_CLIENTID_MASK | i;
> So, it's not a mask, but a flag. Why is it necessary at all? Can you
> just pass i? Or i+1?
This also works as I just need to pass a non-zero unique identifier to DSP.
I'll update this
in the next patch.
Thanks for reviewing.
--ekansh
>
>> break;
>> }
>> }
>> @@ -1504,7 +1507,7 @@ static int fastrpc_release_current_dsp_process(struct
>> fastrpc_user *fl)
>> int tgid = 0;
>> u32 sc;
>>
>> - tgid = fl->tgid;
>> + tgid = fl->client_id;
>> args[0].ptr = (u64)(uintptr_t) &tgid;
>> args[0].length = sizeof(tgid);
>> args[0].fd = -1;
>> @@ -1579,11 +1582,10 @@ static int fastrpc_device_open(struct inode *inode,
>> struct file *filp)
>> INIT_LIST_HEAD(&fl->maps);
>> INIT_LIST_HEAD(&fl->mmaps);
>> INIT_LIST_HEAD(&fl->user);
>> - fl->tgid = current->tgid;
>> fl->cctx = cctx;
>> fl->is_secure_dev = fdevice->secure;
>>
>> - fl->sctx = fastrpc_session_alloc(cctx);
>> + fl->sctx = fastrpc_session_alloc(fl);
>> if (!fl->sctx) {
>> dev_err(&cctx->rpdev->dev, "No session available\n");
>> mutex_destroy(&fl->mutex);
>> @@ -1647,7 +1649,7 @@ static int fastrpc_dmabuf_alloc(struct fastrpc_user
>> *fl, char __user *argp)
>> static int fastrpc_init_attach(struct fastrpc_user *fl, int pd)
>> {
>> struct fastrpc_invoke_args args[1];
>> - int tgid = fl->tgid;
>> + int tgid = fl->client_id;
>> u32 sc;
>>
>> args[0].ptr = (u64)(uintptr_t) &tgid;
>> @@ -1803,7 +1805,7 @@ static int fastrpc_req_munmap_impl(struct fastrpc_user
>> *fl, struct fastrpc_buf *
>> int err;
>> u32 sc;
>>
>> - req_msg.pgid = fl->tgid;
>> + req_msg.pgid = fl->client_id;
>> req_msg.size = buf->size;
>> req_msg.vaddr = buf->raddr;
>>
>> @@ -1889,7 +1891,7 @@ static int fastrpc_req_mmap(struct fastrpc_user *fl,
>> char __user *argp)
>> return err;
>> }
>>
>> - req_msg.pgid = fl->tgid;
>> + req_msg.pgid = fl->client_id;
>> req_msg.flags = req.flags;
>> req_msg.vaddr = req.vaddrin;
>> req_msg.num = sizeof(pages);
>> @@ -1978,7 +1980,7 @@ static int fastrpc_req_mem_unmap_impl(struct
>> fastrpc_user *fl, struct fastrpc_me
>> return -EINVAL;
>> }
>>
>> - req_msg.pgid = fl->tgid;
>> + req_msg.pgid = fl->client_id;
>> req_msg.len = map->len;
>> req_msg.vaddrin = map->raddr;
>> req_msg.fd = map->fd;
>> @@ -2031,7 +2033,7 @@ static int fastrpc_req_mem_map(struct fastrpc_user
>> *fl, char __user *argp)
>> return err;
>> }
>>
>> - req_msg.pgid = fl->tgid;
>> + req_msg.pgid = fl->client_id;
>> req_msg.fd = req.fd;
>> req_msg.offset = req.offset;
>> req_msg.vaddrin = req.vaddrin;
>> --
>> 2.34.1
>>
