[PATCH 2/4] misc: fastrpc: Add secure device node support

From: Jeya R
Date: Fri Sep 24 2021 - 08:19:41 EST


Register and deregister secure device node. Check for device name
during device open get proper channel context.

Signed-off-by: Jeya R <jeyr@xxxxxxxxxxxxxx>
---
drivers/misc/fastrpc.c | 33 +++++++++++++++++++++++++++++++--
1 file changed, 31 insertions(+), 2 deletions(-)

diff --git a/drivers/misc/fastrpc.c b/drivers/misc/fastrpc.c
index beda610..07c41a5 100644
--- a/drivers/misc/fastrpc.c
+++ b/drivers/misc/fastrpc.c
@@ -79,6 +79,7 @@
#define SENSORS_PD (2)

#define miscdev_to_cctx(d) container_of(d, struct fastrpc_channel_ctx, miscdev)
+#define securedev_to_cctx(d) container_of(d, struct fastrpc_channel_ctx, securedev)

static const char *domains[FASTRPC_DEV_MAX] = { "adsp", "mdsp",
"sdsp", "cdsp"};
@@ -213,6 +214,7 @@ struct fastrpc_channel_ctx {
struct idr ctx_idr;
struct list_head users;
struct miscdevice miscdev;
+ struct miscdevice securedev;
struct kref refcount;
};

@@ -1214,10 +1216,23 @@ static int fastrpc_device_release(struct inode *inode, struct file *file)

static int fastrpc_device_open(struct inode *inode, struct file *filp)
{
- struct fastrpc_channel_ctx *cctx = miscdev_to_cctx(filp->private_data);
+ struct fastrpc_channel_ctx *cctx = NULL;
struct fastrpc_user *fl = NULL;
+ struct miscdevice *currdev = NULL;
unsigned long flags;

+ if (!filp)
+ return -EFAULT;
+
+ currdev = (struct miscdevice *)(filp->private_data);
+ if (!currdev)
+ return -EFAULT;
+
+ if (strstr(currdev->name, "secure") != NULL)
+ cctx = securedev_to_cctx(filp->private_data);
+ else
+ cctx = miscdev_to_cctx(filp->private_data);
+
fl = kzalloc(sizeof(*fl), GFP_KERNEL);
if (!fl)
return -ENOMEM;
@@ -1640,6 +1655,15 @@ static int fastrpc_rpmsg_probe(struct rpmsg_device *rpdev)
kfree(data);
return err;
}
+ data->securedev.minor = MISC_DYNAMIC_MINOR;
+ data->securedev.name = devm_kasprintf(rdev, GFP_KERNEL,
+ "fastrpc-%s-secure", domains[domain_id]);
+ data->securedev.fops = &fastrpc_fops;
+ err = misc_register(&data->securedev);
+ if (err) {
+ kfree(data);
+ return err;
+ }

kref_init(&data->refcount);

@@ -1651,7 +1675,11 @@ static int fastrpc_rpmsg_probe(struct rpmsg_device *rpdev)
data->domain_id = domain_id;
data->rpdev = rpdev;

- return of_platform_populate(rdev->of_node, NULL, NULL, rdev);
+ err = of_platform_populate(rdev->of_node, NULL, NULL, rdev);
+ dev_info(rdev, "%s done for %s with nodes non-secure(%d), secure(%d)"
+ "return: %d\n", __func__, domains[domain_id],
+ data->miscdev.minor, data->securedev.minor, err);
+ return err;
}

static void fastrpc_notify_users(struct fastrpc_user *user)
@@ -1676,6 +1704,7 @@ static void fastrpc_rpmsg_remove(struct rpmsg_device *rpdev)
spin_unlock_irqrestore(&cctx->lock, flags);

misc_deregister(&cctx->miscdev);
+ misc_deregister(&cctx->securedev);
of_platform_depopulate(&rpdev->dev);

cctx->rpdev = NULL;
--
2.7.4