[PATCHv3 0/3] optee: register drivers on optee bus

[PATCHv3 0/3] optee: register drivers on optee bus

[Maxim Uvarov]

v3: - support tee-suppicant restart (Jens Wiklander)
    - description and comments ( Jarkko Sakkinen)
    - do not name optee drivers by index in sysfs (Sumit Garg)
v2: - write TEE with capital letters.
    - declare __optee_enumerate_device() as static.

Hello,

This patchset fixes issues with probing() tee, optee and optee driver
if they were compiled into kernel, built as modules or any mixed
combination.
These changes require optee-os changes which already were merged.
Main corresponding commits are:
https://github.com/OP-TEE/optee_os/commit/9389d8030ef198c9d7b8ab7ea8e877e0ace3369d
https://github.com/OP-TEE/optee_os/commit/bc5921cdab538c8ae48422f5ffd600f1cbdd95b2

optee_enumerate_devices() which discovers Trusted Applications on tee
bus is split up on 2 changes. Do probe of drivers which do not require
userspace support of tee-supplicant and stage two to run drivers with
support of tee-supplicant only after tee supplicant run. 

Best regards,
Maxim.
Maxim Uvarov (3):
  optee: do drivers initialization before and after tee-supplicant run
  optee: use uuid for sysfs driver entry
  tpm_ftpm_tee: register driver on TEE bus

 drivers/char/tpm/tpm_ftpm_tee.c   | 70 ++++++++++++++++++++++++++-----
 drivers/tee/optee/core.c          | 28 +++++++++++--
 drivers/tee/optee/device.c        | 23 ++++++----
 drivers/tee/optee/optee_private.h | 10 ++++-
 4 files changed, 108 insertions(+), 23 deletions(-)

-- 
2.17.1

[PATCHv3 1/3] optee: do drivers initialization before and after tee-supplicant run

[Maxim Uvarov]

Some drivers (like ftpm) can operate only after tee-supplicant
runs becase of tee-supplicant provides things like storage
services.  This patch splits probe of non tee-supplicant dependable
drivers to early stage, and after tee-supplicant run probe other
drivers.

Signed-off-by: Maxim Uvarov <maxim.uvarov@linaro.org>
Suggested-by: Sumit Garg <sumit.garg@linaro.org>
Suggested-by: Arnd Bergmann <arnd@linaro.org>
---
 drivers/tee/optee/core.c          | 28 +++++++++++++++++++++++++---
 drivers/tee/optee/device.c        | 17 +++++++++++------
 drivers/tee/optee/optee_private.h | 10 +++++++++-
 3 files changed, 45 insertions(+), 10 deletions(-)

diff --git a/drivers/tee/optee/core.c b/drivers/tee/optee/core.c
index 99698b8a3a74..d059e3ac491c 100644
--- a/drivers/tee/optee/core.c
+++ b/drivers/tee/optee/core.c
@@ -17,6 +17,7 @@
 #include <linux/tee_drv.h>
 #include <linux/types.h>
 #include <linux/uaccess.h>
+#include <linux/workqueue.h>
 #include "optee_private.h"
 #include "optee_smc.h"
 #include "shm_pool.h"
@@ -218,6 +219,15 @@ static void optee_get_version(struct tee_device *teedev,
 	*vers = v;
 }
 
+static void optee_bus_scan(struct work_struct *work)
+{
+	int rc;
+
+	rc = optee_enumerate_devices(PTA_CMD_GET_DEVICES_SUPP);
+	if (rc)
+		pr_err("optee_enumerate_devices failed %d\n", rc);
+}
+
 static int optee_open(struct tee_context *ctx)
 {
 	struct optee_context_data *ctxdata;
@@ -241,8 +251,18 @@ static int optee_open(struct tee_context *ctx)
 			kfree(ctxdata);
 			return -EBUSY;
 		}
-	}
 
+		if (!optee->scan_bus_done) {
+			INIT_WORK(&optee->scan_bus_work, optee_bus_scan);
+			optee->scan_bus_wq = create_workqueue("optee_bus_scan");
+			if (!optee->scan_bus_wq) {
+				pr_err("optee: couldn't create workqueue\n");
+				return -ECHILD;
+			}
+			queue_work(optee->scan_bus_wq, &optee->scan_bus_work);
+			optee->scan_bus_done = true;
+		}
+	}
 	mutex_init(&ctxdata->mutex);
 	INIT_LIST_HEAD(&ctxdata->sess_list);
 
@@ -296,8 +316,10 @@ static void optee_release(struct tee_context *ctx)
 
 	ctx->data = NULL;
 
-	if (teedev == optee->supp_teedev)
+	if (teedev == optee->supp_teedev) {
+		destroy_workqueue(optee->scan_bus_wq);
 		optee_supp_release(&optee->supp);
+	}
 }
 
 static const struct tee_driver_ops optee_ops = {
@@ -675,7 +697,7 @@ static int optee_probe(struct platform_device *pdev)
 
 	platform_set_drvdata(pdev, optee);
 
-	rc = optee_enumerate_devices();
+	rc = optee_enumerate_devices(PTA_CMD_GET_DEVICES);
 	if (rc) {
 		optee_remove(pdev);
 		return rc;
diff --git a/drivers/tee/optee/device.c b/drivers/tee/optee/device.c
index e3a148521ec1..d4931dad07aa 100644
--- a/drivers/tee/optee/device.c
+++ b/drivers/tee/optee/device.c
@@ -21,7 +21,6 @@
  * TEE_ERROR_BAD_PARAMETERS - Incorrect input param
  * TEE_ERROR_SHORT_BUFFER - Output buffer size less than required
  */
-#define PTA_CMD_GET_DEVICES		0x0
 
 static int optee_ctx_match(struct tee_ioctl_version_data *ver, const void *data)
 {
@@ -32,7 +31,8 @@ static int optee_ctx_match(struct tee_ioctl_version_data *ver, const void *data)
 }
 
 static int get_devices(struct tee_context *ctx, u32 session,
-		       struct tee_shm *device_shm, u32 *shm_size)
+		       struct tee_shm *device_shm, u32 *shm_size,
+		       u32 func)
 {
 	int ret = 0;
 	struct tee_ioctl_invoke_arg inv_arg;
@@ -42,7 +42,7 @@ static int get_devices(struct tee_context *ctx, u32 session,
 	memset(&param, 0, sizeof(param));
 
 	/* Invoke PTA_CMD_GET_DEVICES function */
-	inv_arg.func = PTA_CMD_GET_DEVICES;
+	inv_arg.func = func;
 	inv_arg.session = session;
 	inv_arg.num_params = 4;
 
@@ -87,7 +87,7 @@ static int optee_register_device(const uuid_t *device_uuid, u32 device_id)
 	return rc;
 }
 
-int optee_enumerate_devices(void)
+static int __optee_enumerate_devices(u32 func)
 {
 	const uuid_t pta_uuid =
 		UUID_INIT(0x7011a688, 0xddde, 0x4053,
@@ -118,7 +118,7 @@ int optee_enumerate_devices(void)
 		goto out_ctx;
 	}
 
-	rc = get_devices(ctx, sess_arg.session, NULL, &shm_size);
+	rc = get_devices(ctx, sess_arg.session, NULL, &shm_size, func);
 	if (rc < 0 || !shm_size)
 		goto out_sess;
 
@@ -130,7 +130,7 @@ int optee_enumerate_devices(void)
 		goto out_sess;
 	}
 
-	rc = get_devices(ctx, sess_arg.session, device_shm, &shm_size);
+	rc = get_devices(ctx, sess_arg.session, device_shm, &shm_size, func);
 	if (rc < 0)
 		goto out_shm;
 
@@ -158,3 +158,8 @@ int optee_enumerate_devices(void)
 
 	return rc;
 }
+
+int optee_enumerate_devices(u32 func)
+{
+	return  __optee_enumerate_devices(func);
+}
diff --git a/drivers/tee/optee/optee_private.h b/drivers/tee/optee/optee_private.h
index d9c5037b4e03..8b71839a357e 100644
--- a/drivers/tee/optee/optee_private.h
+++ b/drivers/tee/optee/optee_private.h
@@ -78,6 +78,9 @@ struct optee_supp {
  * @memremaped_shm	virtual address of memory in shared memory pool
  * @sec_caps:		secure world capabilities defined by
  *			OPTEE_SMC_SEC_CAP_* in optee_smc.h
+ * @scan_bus_done	flag if device registation was already done.
+ * @scan_bus_wq		workqueue to scan optee bus and register optee drivers
+ * @scan_bus_work	workq to scan optee bus and register optee drivers
  */
 struct optee {
 	struct tee_device *supp_teedev;
@@ -89,6 +92,9 @@ struct optee {
 	struct tee_shm_pool *pool;
 	void *memremaped_shm;
 	u32 sec_caps;
+	bool   scan_bus_done;
+	struct workqueue_struct *scan_bus_wq;
+	struct work_struct scan_bus_work;
 };
 
 struct optee_session {
@@ -173,7 +179,9 @@ void optee_free_pages_list(void *array, size_t num_entries);
 void optee_fill_pages_list(u64 *dst, struct page **pages, int num_pages,
 			   size_t page_offset);
 
-int optee_enumerate_devices(void);
+#define PTA_CMD_GET_DEVICES		0x0
+#define PTA_CMD_GET_DEVICES_SUPP	0x1
+int optee_enumerate_devices(u32 func);
 
 /*
  * Small helpers
-- 
2.17.1

[PATCHv3 2/3] optee: use uuid for sysfs driver entry

[Maxim Uvarov]

Optee device names for sysfs needed to be unique
and it's better if they will mean something. UUID for name
looks like good solution:
/sys/bus/tee/devices/optee-clnt-<uuid>

Signed-off-by: Maxim Uvarov <maxim.uvarov@linaro.org>
---
 drivers/tee/optee/device.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/tee/optee/device.c b/drivers/tee/optee/device.c
index d4931dad07aa..aab917605e74 100644
--- a/drivers/tee/optee/device.c
+++ b/drivers/tee/optee/device.c
@@ -65,7 +65,7 @@ static int get_devices(struct tee_context *ctx, u32 session,
 	return 0;
 }
 
-static int optee_register_device(const uuid_t *device_uuid, u32 device_id)
+static int optee_register_device(const uuid_t *device_uuid)
 {
 	struct tee_client_device *optee_device = NULL;
 	int rc;
@@ -75,7 +75,7 @@ static int optee_register_device(const uuid_t *device_uuid, u32 device_id)
 		return -ENOMEM;
 
 	optee_device->dev.bus = &tee_bus_type;
-	dev_set_name(&optee_device->dev, "optee-clnt%u", device_id);
+	dev_set_name(&optee_device->dev, "optee-clnt-%pUl", device_uuid);
 	uuid_copy(&optee_device->id.uuid, device_uuid);
 
 	rc = device_register(&optee_device->dev);
@@ -144,7 +144,7 @@ static int __optee_enumerate_devices(u32 func)
 	num_devices = shm_size / sizeof(uuid_t);
 
 	for (idx = 0; idx < num_devices; idx++) {
-		rc = optee_register_device(&device_uuid[idx], idx);
+		rc = optee_register_device(&device_uuid[idx]);
 		if (rc)
 			goto out_shm;
 	}
-- 
2.17.1

[PATCHv3 3/3] tpm_ftpm_tee: register driver on TEE bus

[Maxim Uvarov]

Register driver on the TEE bus. The :module tee registers bus,
and module optee calls optee_enumerate_devices() to scan
all devices on the bus. Trusted Application for this driver
can be Early TA's (can be compiled into optee-os). In that
case it will be on OPTEE bus before linux booting. Also
optee-suplicant application is needed to be loaded between
OPTEE module and ftpm module to maintain functionality
for fTPM driver.

Signed-off-by: Maxim Uvarov <maxim.uvarov@linaro.org>
Suggested-by: Sumit Garg <sumit.garg@linaro.org>
Suggested-by: Arnd Bergmann <arnd@linaro.org>
---
 drivers/char/tpm/tpm_ftpm_tee.c | 70 ++++++++++++++++++++++++++++-----
 1 file changed, 60 insertions(+), 10 deletions(-)

diff --git a/drivers/char/tpm/tpm_ftpm_tee.c b/drivers/char/tpm/tpm_ftpm_tee.c
index 22bf553ccf9d..28da638360d8 100644
--- a/drivers/char/tpm/tpm_ftpm_tee.c
+++ b/drivers/char/tpm/tpm_ftpm_tee.c
@@ -214,11 +214,10 @@ static int ftpm_tee_match(struct tee_ioctl_version_data *ver, const void *data)
  * Return:
  *	On success, 0. On failure, -errno.
  */
-static int ftpm_tee_probe(struct platform_device *pdev)
+static int ftpm_tee_probe(struct device *dev)
 {
 	int rc;
 	struct tpm_chip *chip;
-	struct device *dev = &pdev->dev;
 	struct ftpm_tee_private *pvt_data = NULL;
 	struct tee_ioctl_open_session_arg sess_arg;
 
@@ -297,6 +296,13 @@ static int ftpm_tee_probe(struct platform_device *pdev)
 	return rc;
 }
 
+static int ftpm_plat_tee_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+
+	return ftpm_tee_probe(dev);
+}
+
 /**
  * ftpm_tee_remove() - remove the TPM device
  * @pdev: the platform_device description.
@@ -304,9 +310,9 @@ static int ftpm_tee_probe(struct platform_device *pdev)
  * Return:
  *	0 always.
  */
-static int ftpm_tee_remove(struct platform_device *pdev)
+static int ftpm_tee_remove(struct device *dev)
 {
-	struct ftpm_tee_private *pvt_data = dev_get_drvdata(&pdev->dev);
+	struct ftpm_tee_private *pvt_data = dev_get_drvdata(dev);
 
 	/* Release the chip */
 	tpm_chip_unregister(pvt_data->chip);
@@ -328,11 +334,18 @@ static int ftpm_tee_remove(struct platform_device *pdev)
 	return 0;
 }
 
+static int ftpm_plat_tee_remove(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+
+	return ftpm_tee_remove(dev);
+}
+
 /**
  * ftpm_tee_shutdown() - shutdown the TPM device
  * @pdev: the platform_device description.
  */
-static void ftpm_tee_shutdown(struct platform_device *pdev)
+static void ftpm_plat_tee_shutdown(struct platform_device *pdev)
 {
 	struct ftpm_tee_private *pvt_data = dev_get_drvdata(&pdev->dev);
 
@@ -347,17 +360,54 @@ static const struct of_device_id of_ftpm_tee_ids[] = {
 };
 MODULE_DEVICE_TABLE(of, of_ftpm_tee_ids);
 
-static struct platform_driver ftpm_tee_driver = {
+static struct platform_driver ftpm_tee_plat_driver = {
 	.driver = {
 		.name = "ftpm-tee",
 		.of_match_table = of_match_ptr(of_ftpm_tee_ids),
 	},
-	.probe = ftpm_tee_probe,
-	.remove = ftpm_tee_remove,
-	.shutdown = ftpm_tee_shutdown,
+	.shutdown = ftpm_plat_tee_shutdown,
+	.probe = ftpm_plat_tee_probe,
+	.remove = ftpm_plat_tee_remove,
+};
+
+/* UUID of the fTPM TA */
+static const struct tee_client_device_id optee_ftpm_id_table[] = {
+	{UUID_INIT(0xbc50d971, 0xd4c9, 0x42c4,
+		   0x82, 0xcb, 0x34, 0x3f, 0xb7, 0xf3, 0x78, 0x96)},
+	{}
 };
 
-module_platform_driver(ftpm_tee_driver);
+MODULE_DEVICE_TABLE(tee, optee_ftpm_id_table);
+
+static struct tee_client_driver ftpm_tee_driver = {
+	.id_table	= optee_ftpm_id_table,
+	.driver		= {
+		.name		= "optee-ftpm",
+		.bus		= &tee_bus_type,
+		.probe		= ftpm_tee_probe,
+		.remove		= ftpm_tee_remove,
+	},
+};
+
+static int __init ftpm_mod_init(void)
+{
+	int rc;
+
+	rc = platform_driver_register(&ftpm_tee_plat_driver);
+	if (rc)
+		return rc;
+
+	return driver_register(&ftpm_tee_driver.driver);
+}
+
+static void __exit ftpm_mod_exit(void)
+{
+	platform_driver_unregister(&ftpm_tee_plat_driver);
+	driver_unregister(&ftpm_tee_driver.driver);
+}
+
+module_init(ftpm_mod_init);
+module_exit(ftpm_mod_exit);
 
 MODULE_AUTHOR("Thirupathaiah Annapureddy <thiruan@microsoft.com>");
 MODULE_DESCRIPTION("TPM Driver for fTPM TA in TEE");
-- 
2.17.1

Re: [Tee-dev] [PATCHv3 2/3] optee: use uuid for sysfs driver entry

[Jerome Forissier]

On 5/25/20 1:52 PM, Maxim Uvarov wrote:
> Optee device names for sysfs needed to be unique

s/Optee/OP-TEE/
s/needed/need/

> and it's better if they will mean something. UUID for name
> looks like good solution:
> /sys/bus/tee/devices/optee-clnt-<uuid>

How about mentioning it is the UUID of the Trusted Application on the
TEE side?

> 
> Signed-off-by: Maxim Uvarov <maxim.uvarov@linaro.org>
> ---
>  drivers/tee/optee/device.c | 6 +++---
>  1 file changed, 3 insertions(+), 3 deletions(-)

Thanks,
-- 
Jerome

Re: [PATCHv3 2/3] optee: use uuid for sysfs driver entry

[Greg KH]

On Mon, May 25, 2020 at 02:52:34PM +0300, Maxim Uvarov wrote:
> Optee device names for sysfs needed to be unique
> and it's better if they will mean something. UUID for name
> looks like good solution:
> /sys/bus/tee/devices/optee-clnt-<uuid>

Can you document that in Documentation/ABI/ ?

And why UUID?  Those are usually huge, is that easier than just a unique
number?

thanks,

greg k-h

Re: [PATCHv3 2/3] optee: use uuid for sysfs driver entry

[Maxim Uvarov]

On Mon, 25 May 2020 at 15:47, Greg KH <gregkh@linuxfoundation.org> wrote:
>
> On Mon, May 25, 2020 at 02:52:34PM +0300, Maxim Uvarov wrote:
> > Optee device names for sysfs needed to be unique
> > and it's better if they will mean something. UUID for name
> > looks like good solution:
> > /sys/bus/tee/devices/optee-clnt-<uuid>
>
> Can you document that in Documentation/ABI/ ?
>
yes, sure if we agree to go with uuid.

> And why UUID?  Those are usually huge, is that easier than just a unique
> number?
>

UUID here is connected to Trusted Application (TA) in a secure world.
If you need to 'find'  sysfs entry for the corresponding driver
becomes very easy.
Also UUID here are not really huge, like:
/sys/bus/tee/devices/optee-clnt-71d950bc-c9d4-c442-82cb-343fb7f37896
/sys/bus/tee/devices/optee-clnt-ba3ac5b6-6996-6846-a7f2-205629d00f86

I think that is better then optee-clnt-0, optee-clnt-1.. which can be
reordered on each boot and does not carry any information. And on
module unload there will be missing numbers.

Regards,
Maxim.

> thanks,
>
> greg k-h

Re: [Tee-dev] [PATCHv3 2/3] optee: use uuid for sysfs driver entry

[Maxim Uvarov]

On Mon, 25 May 2020 at 15:10, Jerome Forissier <jerome@forissier.org> wrote:
>
>
>
> On 5/25/20 1:52 PM, Maxim Uvarov wrote:
> > Optee device names for sysfs needed to be unique
>
> s/Optee/OP-TEE/
> s/needed/need/
>
> > and it's better if they will mean something. UUID for name
> > looks like good solution:
> > /sys/bus/tee/devices/optee-clnt-<uuid>
>
> How about mentioning it is the UUID of the Trusted Application on the
> TEE side?
>

Jerome, do you think optee-ta-<uuid> is more suitable here?


> >
> > Signed-off-by: Maxim Uvarov <maxim.uvarov@linaro.org>
> > ---
> >  drivers/tee/optee/device.c | 6 +++---
> >  1 file changed, 3 insertions(+), 3 deletions(-)
>
> Thanks,
> --
> Jerome

Re: [Tee-dev] [PATCHv3 2/3] optee: use uuid for sysfs driver entry

[Jerome Forissier]

On 5/25/20 3:36 PM, Maxim Uvarov wrote:
> On Mon, 25 May 2020 at 15:10, Jerome Forissier <jerome@forissier.org> wrote:
>>
>>
>>
>> On 5/25/20 1:52 PM, Maxim Uvarov wrote:
>>> Optee device names for sysfs needed to be unique
>>
>> s/Optee/OP-TEE/
>> s/needed/need/
>>
>>> and it's better if they will mean something. UUID for name
>>> looks like good solution:
>>> /sys/bus/tee/devices/optee-clnt-<uuid>
>>
>> How about mentioning it is the UUID of the Trusted Application on the
>> TEE side?
>>
> 
> Jerome, do you think optee-ta-<uuid> is more suitable here?

Yes, a bit better I think. More "self explanatory"... kind of :)

Is it possible to have several devices bound to the same TA? I think
nothing forbids this although we may not have any use case for now...

-- 
Jerome

Re: [Tee-dev] [PATCHv3 2/3] optee: use uuid for sysfs driver entry

[Sumit Garg]

On Mon, 25 May 2020 at 21:24, Jerome Forissier <jerome@forissier.org> wrote:
>
>
>
> On 5/25/20 3:36 PM, Maxim Uvarov wrote:
> > On Mon, 25 May 2020 at 15:10, Jerome Forissier <jerome@forissier.org> wrote:
> >>
> >>
> >>
> >> On 5/25/20 1:52 PM, Maxim Uvarov wrote:
> >>> Optee device names for sysfs needed to be unique
> >>
> >> s/Optee/OP-TEE/
> >> s/needed/need/
> >>
> >>> and it's better if they will mean something. UUID for name
> >>> looks like good solution:
> >>> /sys/bus/tee/devices/optee-clnt-<uuid>
> >>
> >> How about mentioning it is the UUID of the Trusted Application on the
> >> TEE side?
> >>
> >
> > Jerome, do you think optee-ta-<uuid> is more suitable here?
>
> Yes, a bit better I think. More "self explanatory"... kind of :)
>

+1

> Is it possible to have several devices bound to the same TA? I think
> nothing forbids this although we may not have any use case for now...
>

A single TA is represented via a single device represented via UUID on
the TEE bus. And I can't think of a scenario where the user may not
want to split the TA so as to support a particular driver in Linux.

-Sumit

> --
> Jerome
> _______________________________________________
> Tee-dev mailing list
> Tee-dev@lists.linaro.org
> https://lists.linaro.org/mailman/listinfo/tee-dev

Re: [PATCHv3 1/3] optee: do drivers initialization before and after tee-supplicant run

[Jarkko Sakkinen]

On Mon, 2020-05-25 at 14:52 +0300, Maxim Uvarov wrote:
> Some drivers (like ftpm) can operate only after tee-supplicant
> runs becase of tee-supplicant provides things like storage
> services.  This patch splits probe of non tee-supplicant dependable
> drivers to early stage, and after tee-supplicant run probe other
> drivers.

Fix the typos and remove extra spaces (one space after '.').

Why "tee-supplicant" and not "TEE-supplicant"?

> 
> Signed-off-by: Maxim Uvarov <maxim.uvarov@linaro.org>
> Suggested-by: Sumit Garg <sumit.garg@linaro.org>
> Suggested-by: Arnd Bergmann <arnd@linaro.org>
> ---
>  drivers/tee/optee/core.c          | 28 +++++++++++++++++++++++++---
>  drivers/tee/optee/device.c        | 17 +++++++++++------
>  drivers/tee/optee/optee_private.h | 10 +++++++++-
>  3 files changed, 45 insertions(+), 10 deletions(-)
> 
> diff --git a/drivers/tee/optee/core.c b/drivers/tee/optee/core.c
> index 99698b8a3a74..d059e3ac491c 100644
> --- a/drivers/tee/optee/core.c
> +++ b/drivers/tee/optee/core.c
> @@ -17,6 +17,7 @@
>  #include <linux/tee_drv.h>
>  #include <linux/types.h>
>  #include <linux/uaccess.h>
> +#include <linux/workqueue.h>
>  #include "optee_private.h"
>  #include "optee_smc.h"
>  #include "shm_pool.h"
> @@ -218,6 +219,15 @@ static void optee_get_version(struct tee_device *teedev,
>  	*vers = v;
>  }
>  
> +static void optee_bus_scan(struct work_struct *work)
> +{
> +	int rc;
> +
> +	rc = optee_enumerate_devices(PTA_CMD_GET_DEVICES_SUPP);
> +	if (rc)
> +		pr_err("optee_enumerate_devices failed %d\n", rc);
> +}

Is pr_err() required really here? Why not just pr_info()?

Why have it all and not just ftrace when needed? There is series going
on to add CONFIG_FTRACE_FUNC_PROTOTYPE to that to get return values and
arguments.

> +
>  static int optee_open(struct tee_context *ctx)
>  {
>  	struct optee_context_data *ctxdata;
> @@ -241,8 +251,18 @@ static int optee_open(struct tee_context *ctx)
>  			kfree(ctxdata);
>  			return -EBUSY;
>  		}
> -	}
>  
> +		if (!optee->scan_bus_done) {
> +			INIT_WORK(&optee->scan_bus_work, optee_bus_scan);
> +			optee->scan_bus_wq = create_workqueue("optee_bus_scan");
> +			if (!optee->scan_bus_wq) {
> +				pr_err("optee: couldn't create workqueue\n");

Neither get pr_err() here. Please remove this one completely.

> +				return -ECHILD;
> +			}
> +			queue_work(optee->scan_bus_wq, &optee->scan_bus_work);
> +			optee->scan_bus_done = true;
> +		}
> +	}
>  	mutex_init(&ctxdata->mutex);
>  	INIT_LIST_HEAD(&ctxdata->sess_list);
>  
> @@ -296,8 +316,10 @@ static void optee_release(struct tee_context *ctx)
>  
>  	ctx->data = NULL;
>  
> -	if (teedev == optee->supp_teedev)
> +	if (teedev == optee->supp_teedev) {
> +		destroy_workqueue(optee->scan_bus_wq);
>  		optee_supp_release(&optee->supp);
> +	}
>  }
>  
>  static const struct tee_driver_ops optee_ops = {
> @@ -675,7 +697,7 @@ static int optee_probe(struct platform_device *pdev)
>  
>  	platform_set_drvdata(pdev, optee);
>  
> -	rc = optee_enumerate_devices();
> +	rc = optee_enumerate_devices(PTA_CMD_GET_DEVICES);
>  	if (rc) {
>  		optee_remove(pdev);
>  		return rc;
> diff --git a/drivers/tee/optee/device.c b/drivers/tee/optee/device.c
> index e3a148521ec1..d4931dad07aa 100644
> --- a/drivers/tee/optee/device.c
> +++ b/drivers/tee/optee/device.c
> @@ -21,7 +21,6 @@
>   * TEE_ERROR_BAD_PARAMETERS - Incorrect input param
>   * TEE_ERROR_SHORT_BUFFER - Output buffer size less than required
>   */
> -#define PTA_CMD_GET_DEVICES		0x0
>  
>  static int optee_ctx_match(struct tee_ioctl_version_data *ver, const void *data)
>  {
> @@ -32,7 +31,8 @@ static int optee_ctx_match(struct tee_ioctl_version_data *ver, const void *data)
>  }
>  
>  static int get_devices(struct tee_context *ctx, u32 session,
> -		       struct tee_shm *device_shm, u32 *shm_size)
> +		       struct tee_shm *device_shm, u32 *shm_size,
> +		       u32 func)
>  {
>  	int ret = 0;
>  	struct tee_ioctl_invoke_arg inv_arg;
> @@ -42,7 +42,7 @@ static int get_devices(struct tee_context *ctx, u32 session,
>  	memset(&param, 0, sizeof(param));
>  
>  	/* Invoke PTA_CMD_GET_DEVICES function */
> -	inv_arg.func = PTA_CMD_GET_DEVICES;
> +	inv_arg.func = func;
>  	inv_arg.session = session;
>  	inv_arg.num_params = 4;
>  
> @@ -87,7 +87,7 @@ static int optee_register_device(const uuid_t *device_uuid, u32 device_id)
>  	return rc;
>  }
>  
> -int optee_enumerate_devices(void)
> +static int __optee_enumerate_devices(u32 func)
>  {
>  	const uuid_t pta_uuid =
>  		UUID_INIT(0x7011a688, 0xddde, 0x4053,
> @@ -118,7 +118,7 @@ int optee_enumerate_devices(void)
>  		goto out_ctx;
>  	}
>  
> -	rc = get_devices(ctx, sess_arg.session, NULL, &shm_size);
> +	rc = get_devices(ctx, sess_arg.session, NULL, &shm_size, func);
>  	if (rc < 0 || !shm_size)
>  		goto out_sess;
>  
> @@ -130,7 +130,7 @@ int optee_enumerate_devices(void)
>  		goto out_sess;
>  	}
>  
> -	rc = get_devices(ctx, sess_arg.session, device_shm, &shm_size);
> +	rc = get_devices(ctx, sess_arg.session, device_shm, &shm_size, func);
>  	if (rc < 0)
>  		goto out_shm;
>  
> @@ -158,3 +158,8 @@ int optee_enumerate_devices(void)
>  
>  	return rc;
>  }
> +
> +int optee_enumerate_devices(u32 func)
> +{
> +	return  __optee_enumerate_devices(func);
> +}
> diff --git a/drivers/tee/optee/optee_private.h b/drivers/tee/optee/optee_private.h
> index d9c5037b4e03..8b71839a357e 100644
> --- a/drivers/tee/optee/optee_private.h
> +++ b/drivers/tee/optee/optee_private.h
> @@ -78,6 +78,9 @@ struct optee_supp {
>   * @memremaped_shm	virtual address of memory in shared memory pool
>   * @sec_caps:		secure world capabilities defined by
>   *			OPTEE_SMC_SEC_CAP_* in optee_smc.h
> + * @scan_bus_done	flag if device registation was already done.
> + * @scan_bus_wq		workqueue to scan optee bus and register optee drivers
> + * @scan_bus_work	workq to scan optee bus and register optee drivers
>   */
>  struct optee {
>  	struct tee_device *supp_teedev;
> @@ -89,6 +92,9 @@ struct optee {
>  	struct tee_shm_pool *pool;
>  	void *memremaped_shm;
>  	u32 sec_caps;
> +	bool   scan_bus_done;
> +	struct workqueue_struct *scan_bus_wq;
> +	struct work_struct scan_bus_work;
>  };
>  
>  struct optee_session {
> @@ -173,7 +179,9 @@ void optee_free_pages_list(void *array, size_t num_entries);
>  void optee_fill_pages_list(u64 *dst, struct page **pages, int num_pages,
>  			   size_t page_offset);
>  
> -int optee_enumerate_devices(void);
> +#define PTA_CMD_GET_DEVICES		0x0
> +#define PTA_CMD_GET_DEVICES_SUPP	0x1
> +int optee_enumerate_devices(u32 func);
>  
>  /*
>   * Small helpers

No exalanation of "scan bus" neither in the comments nor in the code.

/Jarkko

Re: [PATCHv3 1/3] optee: do drivers initialization before and after tee-supplicant run

[Maxim Uvarov]

On Wed, 27 May 2020 at 22:56, Jarkko Sakkinen
<jarkko.sakkinen@linux.intel.com> wrote:
>
> On Mon, 2020-05-25 at 14:52 +0300, Maxim Uvarov wrote:
> > Some drivers (like ftpm) can operate only after tee-supplicant
> > runs becase of tee-supplicant provides things like storage
> > services.  This patch splits probe of non tee-supplicant dependable
> > drivers to early stage, and after tee-supplicant run probe other
> > drivers.
>
> Fix the typos and remove extra spaces (one space after '.').
>
> Why "tee-supplicant" and not "TEE-supplicant"?
>
> >
> > Signed-off-by: Maxim Uvarov <maxim.uvarov@linaro.org>
> > Suggested-by: Sumit Garg <sumit.garg@linaro.org>
> > Suggested-by: Arnd Bergmann <arnd@linaro.org>
> > ---
> >  drivers/tee/optee/core.c          | 28 +++++++++++++++++++++++++---
> >  drivers/tee/optee/device.c        | 17 +++++++++++------
> >  drivers/tee/optee/optee_private.h | 10 +++++++++-
> >  3 files changed, 45 insertions(+), 10 deletions(-)
> >
> > diff --git a/drivers/tee/optee/core.c b/drivers/tee/optee/core.c
> > index 99698b8a3a74..d059e3ac491c 100644
> > --- a/drivers/tee/optee/core.c
> > +++ b/drivers/tee/optee/core.c
> > @@ -17,6 +17,7 @@
> >  #include <linux/tee_drv.h>
> >  #include <linux/types.h>
> >  #include <linux/uaccess.h>
> > +#include <linux/workqueue.h>
> >  #include "optee_private.h"
> >  #include "optee_smc.h"
> >  #include "shm_pool.h"
> > @@ -218,6 +219,15 @@ static void optee_get_version(struct tee_device *teedev,
> >       *vers = v;
> >  }
> >
> > +static void optee_bus_scan(struct work_struct *work)
> > +{
> > +     int rc;
> > +
> > +     rc = optee_enumerate_devices(PTA_CMD_GET_DEVICES_SUPP);
> > +     if (rc)
> > +             pr_err("optee_enumerate_devices failed %d\n", rc);
> > +}
>
> Is pr_err() required really here? Why not just pr_info()?
>
> Why have it all and not just ftrace when needed? There is series going
> on to add CONFIG_FTRACE_FUNC_PROTOTYPE to that to get return values and
> arguments.
>

Actually if  optee_enumerate_devices() fail then I would say there is
something wrong with memory or Secure OS and more likely we should
stop execution.
I think something line WARN_ON might be more suitable here. What do you think?

> > +
> >  static int optee_open(struct tee_context *ctx)
> >  {
> >       struct optee_context_data *ctxdata;
> > @@ -241,8 +251,18 @@ static int optee_open(struct tee_context *ctx)
> >                       kfree(ctxdata);
> >                       return -EBUSY;
> >               }
> > -     }
> >
> > +             if (!optee->scan_bus_done) {
> > +                     INIT_WORK(&optee->scan_bus_work, optee_bus_scan);
> > +                     optee->scan_bus_wq = create_workqueue("optee_bus_scan");
> > +                     if (!optee->scan_bus_wq) {
> > +                             pr_err("optee: couldn't create workqueue\n");
>
> Neither get pr_err() here. Please remove this one completely.
>

What is the benefit of removing print here? Kernel binary size?

> > +                             return -ECHILD;
> > +                     }
> > +                     queue_work(optee->scan_bus_wq, &optee->scan_bus_work);
> > +                     optee->scan_bus_done = true;
> > +             }
> > +     }
> >       mutex_init(&ctxdata->mutex);
> >       INIT_LIST_HEAD(&ctxdata->sess_list);
> >
> > @@ -296,8 +316,10 @@ static void optee_release(struct tee_context *ctx)
> >
> >       ctx->data = NULL;
> >
> > -     if (teedev == optee->supp_teedev)
> > +     if (teedev == optee->supp_teedev) {
> > +             destroy_workqueue(optee->scan_bus_wq);
> >               optee_supp_release(&optee->supp);
> > +     }
> >  }
> >
> >  static const struct tee_driver_ops optee_ops = {
> > @@ -675,7 +697,7 @@ static int optee_probe(struct platform_device *pdev)
> >
> >       platform_set_drvdata(pdev, optee);
> >
> > -     rc = optee_enumerate_devices();
> > +     rc = optee_enumerate_devices(PTA_CMD_GET_DEVICES);
> >       if (rc) {
> >               optee_remove(pdev);
> >               return rc;
> > diff --git a/drivers/tee/optee/device.c b/drivers/tee/optee/device.c
> > index e3a148521ec1..d4931dad07aa 100644
> > --- a/drivers/tee/optee/device.c
> > +++ b/drivers/tee/optee/device.c
> > @@ -21,7 +21,6 @@
> >   * TEE_ERROR_BAD_PARAMETERS - Incorrect input param
> >   * TEE_ERROR_SHORT_BUFFER - Output buffer size less than required
> >   */
> > -#define PTA_CMD_GET_DEVICES          0x0
> >
> >  static int optee_ctx_match(struct tee_ioctl_version_data *ver, const void *data)
> >  {
> > @@ -32,7 +31,8 @@ static int optee_ctx_match(struct tee_ioctl_version_data *ver, const void *data)
> >  }
> >
> >  static int get_devices(struct tee_context *ctx, u32 session,
> > -                    struct tee_shm *device_shm, u32 *shm_size)
> > +                    struct tee_shm *device_shm, u32 *shm_size,
> > +                    u32 func)
> >  {
> >       int ret = 0;
> >       struct tee_ioctl_invoke_arg inv_arg;
> > @@ -42,7 +42,7 @@ static int get_devices(struct tee_context *ctx, u32 session,
> >       memset(&param, 0, sizeof(param));
> >
> >       /* Invoke PTA_CMD_GET_DEVICES function */
> > -     inv_arg.func = PTA_CMD_GET_DEVICES;
> > +     inv_arg.func = func;
> >       inv_arg.session = session;
> >       inv_arg.num_params = 4;
> >
> > @@ -87,7 +87,7 @@ static int optee_register_device(const uuid_t *device_uuid, u32 device_id)
> >       return rc;
> >  }
> >
> > -int optee_enumerate_devices(void)
> > +static int __optee_enumerate_devices(u32 func)
> >  {
> >       const uuid_t pta_uuid =
> >               UUID_INIT(0x7011a688, 0xddde, 0x4053,
> > @@ -118,7 +118,7 @@ int optee_enumerate_devices(void)
> >               goto out_ctx;
> >       }
> >
> > -     rc = get_devices(ctx, sess_arg.session, NULL, &shm_size);
> > +     rc = get_devices(ctx, sess_arg.session, NULL, &shm_size, func);
> >       if (rc < 0 || !shm_size)
> >               goto out_sess;
> >
> > @@ -130,7 +130,7 @@ int optee_enumerate_devices(void)
> >               goto out_sess;
> >       }
> >
> > -     rc = get_devices(ctx, sess_arg.session, device_shm, &shm_size);
> > +     rc = get_devices(ctx, sess_arg.session, device_shm, &shm_size, func);
> >       if (rc < 0)
> >               goto out_shm;
> >
> > @@ -158,3 +158,8 @@ int optee_enumerate_devices(void)
> >
> >       return rc;
> >  }
> > +
> > +int optee_enumerate_devices(u32 func)
> > +{
> > +     return  __optee_enumerate_devices(func);
> > +}
> > diff --git a/drivers/tee/optee/optee_private.h b/drivers/tee/optee/optee_private.h
> > index d9c5037b4e03..8b71839a357e 100644
> > --- a/drivers/tee/optee/optee_private.h
> > +++ b/drivers/tee/optee/optee_private.h
> > @@ -78,6 +78,9 @@ struct optee_supp {
> >   * @memremaped_shm   virtual address of memory in shared memory pool
> >   * @sec_caps:                secure world capabilities defined by
> >   *                   OPTEE_SMC_SEC_CAP_* in optee_smc.h
> > + * @scan_bus_done    flag if device registation was already done.
> > + * @scan_bus_wq              workqueue to scan optee bus and register optee drivers
> > + * @scan_bus_work    workq to scan optee bus and register optee drivers
> >   */
> >  struct optee {
> >       struct tee_device *supp_teedev;
> > @@ -89,6 +92,9 @@ struct optee {
> >       struct tee_shm_pool *pool;
> >       void *memremaped_shm;
> >       u32 sec_caps;
> > +     bool   scan_bus_done;
> > +     struct workqueue_struct *scan_bus_wq;
> > +     struct work_struct scan_bus_work;
> >  };
> >
> >  struct optee_session {
> > @@ -173,7 +179,9 @@ void optee_free_pages_list(void *array, size_t num_entries);
> >  void optee_fill_pages_list(u64 *dst, struct page **pages, int num_pages,
> >                          size_t page_offset);
> >
> > -int optee_enumerate_devices(void);
> > +#define PTA_CMD_GET_DEVICES          0x0
> > +#define PTA_CMD_GET_DEVICES_SUPP     0x1
> > +int optee_enumerate_devices(u32 func);
> >
> >  /*
> >   * Small helpers
>
> No exalanation of "scan bus" neither in the comments nor in the code.
>

Idea was when tee-supplicant opens /dev/tee-priv0 then we run
workqueue (to not hold current open()) and do bus scan for TA
applications which require tee-supplicant run. There is no "scan bus"
as API. The is optee_enumerate_devices() is split up on 2 stages.

Maxim.

> /Jarkko
>