From: Stanimir Varbanov <stanimir.varbanov@linaro.org>
Date: Fri, 4 Dec 2020 10:01:37 +0000 (+0100)
Subject: media: venus: Limit HFI sessions to the maximum supported
X-Git-Tag: v5.10.237~83
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=94ce606d01e45e8a113fbb371f0b5cc2d53942b5;p=thirdparty%2Fkernel%2Fstable.git

media: venus: Limit HFI sessions to the maximum supported

[ Upstream commit 20891170f339a8754312a877f3d17f0e5dadd599 ]

Currently we rely on firmware to return error when we reach the maximum
supported number of sessions. But this errors are happened at reqbuf
time which is a bit later. The more reasonable way looks like is to
return the error on driver open.

To achieve that modify hfi_session_create to return error when we reach
maximum count of sessions and thus refuse open.

Tested-by: Fritz Koenig <frkoenig@chromium.org>
Signed-off-by: Stanimir Varbanov <stanimir.varbanov@linaro.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Stable-dep-of: 9edaaa8e3e15 ("media: venus: hfi_parser: refactor hfi packet parsing logic")
Signed-off-by: Sasha Levin <sashal@kernel.org>
---

diff --git a/drivers/media/platform/qcom/venus/core.h b/drivers/media/platform/qcom/venus/core.h
index 75d0068033276..e56d7b8142152 100644
--- a/drivers/media/platform/qcom/venus/core.h
+++ b/drivers/media/platform/qcom/venus/core.h
@@ -96,6 +96,7 @@ struct venus_format {
 #define MAX_CAP_ENTRIES		32
 #define MAX_ALLOC_MODE_ENTRIES	16
 #define MAX_CODEC_NUM		32
+#define MAX_SESSIONS		16
 
 struct raw_formats {
 	u32 buftype;
diff --git a/drivers/media/platform/qcom/venus/hfi.c b/drivers/media/platform/qcom/venus/hfi.c
index 966b4d9b57a97..17da555905e98 100644
--- a/drivers/media/platform/qcom/venus/hfi.c
+++ b/drivers/media/platform/qcom/venus/hfi.c
@@ -178,6 +178,8 @@ static int wait_session_msg(struct venus_inst *inst)
 int hfi_session_create(struct venus_inst *inst, const struct hfi_inst_ops *ops)
 {
 	struct venus_core *core = inst->core;
+	bool max;
+	int ret;
 
 	if (!ops)
 		return -EINVAL;
@@ -187,11 +189,19 @@ int hfi_session_create(struct venus_inst *inst, const struct hfi_inst_ops *ops)
 	inst->ops = ops;
 
 	mutex_lock(&core->lock);
-	list_add_tail(&inst->list, &core->instances);
-	atomic_inc(&core->insts_count);
+
+	max = atomic_add_unless(&core->insts_count, 1,
+				core->max_sessions_supported);
+	if (!max) {
+		ret = -EAGAIN;
+	} else {
+		list_add_tail(&inst->list, &core->instances);
+		ret = 0;
+	}
+
 	mutex_unlock(&core->lock);
 
-	return 0;
+	return ret;
 }
 EXPORT_SYMBOL_GPL(hfi_session_create);
 
diff --git a/drivers/media/platform/qcom/venus/hfi_parser.c b/drivers/media/platform/qcom/venus/hfi_parser.c
index 32d2a9ed44003..94981a5e8e9af 100644
--- a/drivers/media/platform/qcom/venus/hfi_parser.c
+++ b/drivers/media/platform/qcom/venus/hfi_parser.c
@@ -295,6 +295,9 @@ u32 hfi_parser(struct venus_core *core, struct venus_inst *inst, void *buf,
 		words_count--;
 	}
 
+	if (!core->max_sessions_supported)
+		core->max_sessions_supported = MAX_SESSIONS;
+
 	parser_fini(inst, codecs, domain);
 
 	return HFI_ERR_NONE;