[v8,4/4] optee: probe RPMB device using RPMB subsystem

Adds support in the OP-TEE drivers (both SMC and FF-A ABIs) to probe and
use an RPMB device via the RPMB subsystem instead of passing the RPMB
frames via tee-supplicant in user space. A fallback mechanism is kept to
route RPMB frames via tee-supplicant if the RPMB subsystem isn't
available.

The OP-TEE RPC ABI is extended to support iterating over all RPMB
devices until one is found with the expected RPMB key already
programmed.

Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>
Tested-by: Manuel Traut <manut@mecka.net>
---
 Documentation/ABI/testing/sysfs-class-tee |  15 ++
 MAINTAINERS                               |   1 +
 drivers/tee/optee/core.c                  |  96 +++++++++++-
 drivers/tee/optee/device.c                |   7 +
 drivers/tee/optee/ffa_abi.c               |  14 ++
 drivers/tee/optee/optee_ffa.h             |   2 +
 drivers/tee/optee/optee_private.h         |  26 +++-
 drivers/tee/optee/optee_rpc_cmd.h         |  35 +++++
 drivers/tee/optee/optee_smc.h             |   2 +
 drivers/tee/optee/rpc.c                   | 177 ++++++++++++++++++++++
 drivers/tee/optee/smc_abi.c               |  14 ++
 11 files changed, 387 insertions(+), 2 deletions(-)
 create mode 100644 Documentation/ABI/testing/sysfs-class-tee

Hi Jens,

On Mon, 12 Aug 2024 at 19:01, Jens Wiklander <jens.wiklander@linaro.org> wrote:
>
> Adds support in the OP-TEE drivers (both SMC and FF-A ABIs) to probe and
> use an RPMB device via the RPMB subsystem instead of passing the RPMB
> frames via tee-supplicant in user space. A fallback mechanism is kept to
> route RPMB frames via tee-supplicant if the RPMB subsystem isn't
> available.
>
> The OP-TEE RPC ABI is extended to support iterating over all RPMB
> devices until one is found with the expected RPMB key already
> programmed.
>
> Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>
> Tested-by: Manuel Traut <manut@mecka.net>
> ---
>  Documentation/ABI/testing/sysfs-class-tee |  15 ++
>  MAINTAINERS                               |   1 +
>  drivers/tee/optee/core.c                  |  96 +++++++++++-
>  drivers/tee/optee/device.c                |   7 +
>  drivers/tee/optee/ffa_abi.c               |  14 ++
>  drivers/tee/optee/optee_ffa.h             |   2 +
>  drivers/tee/optee/optee_private.h         |  26 +++-
>  drivers/tee/optee/optee_rpc_cmd.h         |  35 +++++
>  drivers/tee/optee/optee_smc.h             |   2 +
>  drivers/tee/optee/rpc.c                   | 177 ++++++++++++++++++++++
>  drivers/tee/optee/smc_abi.c               |  14 ++
>  11 files changed, 387 insertions(+), 2 deletions(-)
>  create mode 100644 Documentation/ABI/testing/sysfs-class-tee
>
> diff --git a/Documentation/ABI/testing/sysfs-class-tee b/Documentation/ABI/testing/sysfs-class-tee
> new file mode 100644
> index 000000000000..c9144d16003e
> --- /dev/null
> +++ b/Documentation/ABI/testing/sysfs-class-tee
> @@ -0,0 +1,15 @@
> +What:          /sys/class/tee/tee{,priv}X/rpmb_routing_model
> +Date:          May 2024
> +KernelVersion: 6.10
> +Contact:        op-tee@lists.trustedfirmware.org
> +Description:
> +               RPMB frames can be routed to the RPMB device via the
> +               user-space daemon tee-supplicant or the RPMB subsystem
> +               in the kernel. The value "user" means that the driver
> +               will route the RPMB frames via user space. Conversely,
> +               "kernel" means that the frames are routed via the RPMB
> +               subsystem without assistance from tee-supplicant. It
> +               should be assumed that RPMB frames are routed via user
> +               space if the variable is absent. The primary purpose
> +               of this variable is to let systemd know whether
> +               tee-supplicant is needed in the early boot with initramfs.

Okay, I get the major purpose of this sysfs property is to retain
backwards compatibility with older kernels.

> diff --git a/MAINTAINERS b/MAINTAINERS
> index 716011964b18..d692417edab1 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -22433,6 +22433,7 @@ M:      Jens Wiklander <jens.wiklander@linaro.org>
>  R:     Sumit Garg <sumit.garg@linaro.org>
>  L:     op-tee@lists.trustedfirmware.org
>  S:     Maintained
> +F:     Documentation/ABI/testing/sysfs-class-tee
>  F:     Documentation/driver-api/tee.rst
>  F:     Documentation/tee/
>  F:     Documentation/userspace-api/tee.rst
> diff --git a/drivers/tee/optee/core.c b/drivers/tee/optee/core.c
> index 39e688d4e974..935f3fff9046 100644
> --- a/drivers/tee/optee/core.c
> +++ b/drivers/tee/optee/core.c
> @@ -10,17 +10,85 @@
>  #include <linux/errno.h>
>  #include <linux/io.h>
>  #include <linux/module.h>
> +#include <linux/rpmb.h>
>  #include <linux/slab.h>
>  #include <linux/string.h>
>  #include <linux/tee_core.h>
>  #include <linux/types.h>
>  #include "optee_private.h"
>
> +struct blocking_notifier_head optee_rpmb_intf_added =
> +       BLOCKING_NOTIFIER_INIT(optee_rpmb_intf_added);
> +
> +static int rpmb_add_dev(struct device *dev)
> +{
> +       blocking_notifier_call_chain(&optee_rpmb_intf_added, 0,
> +                                    to_rpmb_dev(dev));
> +
> +       return 0;
> +}
> +
> +static struct class_interface rpmb_class_intf = {
> +       .add_dev = rpmb_add_dev,
> +};
> +
> +void optee_bus_scan_rpmb(struct work_struct *work)
> +{
> +       struct optee *optee = container_of(work, struct optee,
> +                                          rpmb_scan_bus_work);
> +       int ret;
> +
> +       if (!optee->rpmb_scan_bus_done) {
> +               ret = optee_enumerate_devices(PTA_CMD_GET_DEVICES_RPMB);
> +               optee->rpmb_scan_bus_done = !ret;
> +               if (ret && ret != -ENODEV)
> +                       pr_info("Scanning for RPMB device: ret %d\n", ret);
> +       }
> +}
> +
> +int optee_rpmb_intf_rdev(struct notifier_block *intf, unsigned long action,
> +                        void *data)
> +{
> +       struct optee *optee = container_of(intf, struct optee, rpmb_intf);
> +
> +       schedule_work(&optee->rpmb_scan_bus_work);
> +
> +       return 0;
> +}
> +
>  static void optee_bus_scan(struct work_struct *work)
>  {
>         WARN_ON(optee_enumerate_devices(PTA_CMD_GET_DEVICES_SUPP));
>  }
>
> +static ssize_t rpmb_routing_model_show(struct device *dev,
> +                                      struct device_attribute *attr, char *buf)
> +{
> +       struct optee *optee = dev_get_drvdata(dev);
> +       const char *s;
> +
> +       if (optee->in_kernel_rpmb_routing)
> +               s = "kernel";
> +       else
> +               s = "user";
> +
> +       return scnprintf(buf, PAGE_SIZE, "%s\n", s);
> +}
> +static DEVICE_ATTR_RO(rpmb_routing_model);
> +
> +static struct attribute *optee_dev_attrs[] = {
> +       &dev_attr_rpmb_routing_model.attr,
> +       NULL
> +};
> +
> +ATTRIBUTE_GROUPS(optee_dev);
> +
> +void optee_set_dev_group(struct optee *optee)
> +{
> +       tee_device_set_dev_groups(optee->teedev, optee_dev_groups);
> +       tee_device_set_dev_groups(optee->supp_teedev, optee_dev_groups);
> +}
> +
>  int optee_open(struct tee_context *ctx, bool cap_memref_null)
>  {
>         struct optee_context_data *ctxdata;
> @@ -97,6 +165,9 @@ void optee_release_supp(struct tee_context *ctx)
>
>  void optee_remove_common(struct optee *optee)
>  {
> +       blocking_notifier_chain_unregister(&optee_rpmb_intf_added,
> +                                          &optee->rpmb_intf);
> +       cancel_work_sync(&optee->rpmb_scan_bus_work);
>         /* Unregister OP-TEE specific client devices on TEE bus */
>         optee_unregister_devices();
>
> @@ -113,13 +184,18 @@ void optee_remove_common(struct optee *optee)
>         tee_shm_pool_free(optee->pool);
>         optee_supp_uninit(&optee->supp);
>         mutex_destroy(&optee->call_queue.mutex);
> +       rpmb_dev_put(optee->rpmb_dev);
> +       mutex_destroy(&optee->rpmb_dev_mutex);
>  }
>
>  static int smc_abi_rc;
>  static int ffa_abi_rc;
> +static bool intf_is_regged;
>
>  static int __init optee_core_init(void)
>  {
> +       int rc;
> +
>         /*
>          * The kernel may have crashed at the same time that all available
>          * secure world threads were suspended and we cannot reschedule the
> @@ -130,18 +206,36 @@ static int __init optee_core_init(void)
>         if (is_kdump_kernel())
>                 return -ENODEV;
>
> +       if (IS_ENABLED(CONFIG_RPMB)) {

As commented earlier, s/IS_ENABLED/IS_REACHABLE/ here and other places
where checking for CONFIG_RPMB is done.

With those fixed, feel free to add:

Reviewed-by: Sumit Garg <sumit.garg@linaro.org>

> +               rc = rpmb_interface_register(&rpmb_class_intf);
> +               if (rc)
> +                       return rc;
> +               intf_is_regged = true;
> +       }
> +
>         smc_abi_rc = optee_smc_abi_register();
>         ffa_abi_rc = optee_ffa_abi_register();
>
>         /* If both failed there's no point with this module */
> -       if (smc_abi_rc && ffa_abi_rc)
> +       if (smc_abi_rc && ffa_abi_rc) {
> +               if (IS_ENABLED(CONFIG_RPMB)) {
> +                       rpmb_interface_unregister(&rpmb_class_intf);
> +                       intf_is_regged = false;
> +               }
>                 return smc_abi_rc;
> +       }
> +
>         return 0;
>  }
>  module_init(optee_core_init);
>
>  static void __exit optee_core_exit(void)
>  {
> +       if (IS_ENABLED(CONFIG_RPMB) && intf_is_regged) {
> +               rpmb_interface_unregister(&rpmb_class_intf);
> +               intf_is_regged = false;
> +       }
> +
>         if (!smc_abi_rc)
>                 optee_smc_abi_unregister();
>         if (!ffa_abi_rc)
> diff --git a/drivers/tee/optee/device.c b/drivers/tee/optee/device.c
> index d296c70ddfdc..950b4661d5df 100644
> --- a/drivers/tee/optee/device.c
> +++ b/drivers/tee/optee/device.c
> @@ -43,6 +43,13 @@ static int get_devices(struct tee_context *ctx, u32 session,
>         ret = tee_client_invoke_func(ctx, &inv_arg, param);
>         if ((ret < 0) || ((inv_arg.ret != TEEC_SUCCESS) &&
>                           (inv_arg.ret != TEEC_ERROR_SHORT_BUFFER))) {
> +               /*
> +                * TEE_ERROR_STORAGE_NOT_AVAILABLE is returned when getting
> +                * the list of device TAs that depends on RPMB but a usable
> +                * RPMB device isn't found.
> +                */
> +               if (inv_arg.ret == TEE_ERROR_STORAGE_NOT_AVAILABLE)
> +                       return -ENODEV;
>                 pr_err("PTA_CMD_GET_DEVICES invoke function err: %x\n",
>                        inv_arg.ret);
>                 return -EINVAL;
> diff --git a/drivers/tee/optee/ffa_abi.c b/drivers/tee/optee/ffa_abi.c
> index 3e73efa51bba..f3af5666bb11 100644
> --- a/drivers/tee/optee/ffa_abi.c
> +++ b/drivers/tee/optee/ffa_abi.c
> @@ -7,6 +7,7 @@
>
>  #include <linux/arm_ffa.h>
>  #include <linux/errno.h>
> +#include <linux/rpmb.h>
>  #include <linux/scatterlist.h>
>  #include <linux/sched.h>
>  #include <linux/slab.h>
> @@ -909,6 +910,10 @@ static int optee_ffa_probe(struct ffa_device *ffa_dev)
>         optee->ffa.bottom_half_value = U32_MAX;
>         optee->rpc_param_count = rpc_param_count;
>
> +       if (IS_REACHABLE(CONFIG_RPMB) &&

Like this one.

> +           (sec_caps & OPTEE_FFA_SEC_CAP_RPMB_PROBE))
> +               optee->in_kernel_rpmb_routing = true;
> +
>         teedev = tee_device_alloc(&optee_ffa_clnt_desc, NULL, optee->pool,
>                                   optee);
>         if (IS_ERR(teedev)) {
> @@ -925,6 +930,8 @@ static int optee_ffa_probe(struct ffa_device *ffa_dev)
>         }
>         optee->supp_teedev = teedev;
>
> +       optee_set_dev_group(optee);
> +
>         rc = tee_device_register(optee->teedev);
>         if (rc)
>                 goto err_unreg_supp_teedev;
> @@ -940,6 +947,7 @@ static int optee_ffa_probe(struct ffa_device *ffa_dev)
>         optee_cq_init(&optee->call_queue, 0);
>         optee_supp_init(&optee->supp);
>         optee_shm_arg_cache_init(optee, arg_cache_flags);
> +       mutex_init(&optee->rpmb_dev_mutex);
>         ffa_dev_set_drvdata(ffa_dev, optee);
>         ctx = teedev_open(optee->teedev);
>         if (IS_ERR(ctx)) {
> @@ -961,6 +969,10 @@ static int optee_ffa_probe(struct ffa_device *ffa_dev)
>         if (rc)
>                 goto err_unregister_devices;
>
> +       INIT_WORK(&optee->rpmb_scan_bus_work, optee_bus_scan_rpmb);
> +       optee->rpmb_intf.notifier_call = optee_rpmb_intf_rdev;
> +       blocking_notifier_chain_register(&optee_rpmb_intf_added,
> +                                        &optee->rpmb_intf);
>         pr_info("initialized driver\n");
>         return 0;
>
> @@ -974,6 +986,8 @@ static int optee_ffa_probe(struct ffa_device *ffa_dev)
>         teedev_close_context(ctx);
>  err_rhashtable_free:
>         rhashtable_free_and_destroy(&optee->ffa.global_ids, rh_free_fn, NULL);
> +       rpmb_dev_put(optee->rpmb_dev);
> +       mutex_destroy(&optee->rpmb_dev_mutex);
>         optee_supp_uninit(&optee->supp);
>         mutex_destroy(&optee->call_queue.mutex);
>         mutex_destroy(&optee->ffa.mutex);
> diff --git a/drivers/tee/optee/optee_ffa.h b/drivers/tee/optee/optee_ffa.h
> index 5db779dc00de..257735ae5b56 100644
> --- a/drivers/tee/optee/optee_ffa.h
> +++ b/drivers/tee/optee/optee_ffa.h
> @@ -92,6 +92,8 @@
>  #define OPTEE_FFA_SEC_CAP_ARG_OFFSET   BIT(0)
>  /* OP-TEE supports asynchronous notification via FF-A */
>  #define OPTEE_FFA_SEC_CAP_ASYNC_NOTIF  BIT(1)
> +/* OP-TEE supports probing for RPMB device if needed */
> +#define OPTEE_FFA_SEC_CAP_RPMB_PROBE   BIT(2)
>
>  #define OPTEE_FFA_EXCHANGE_CAPABILITIES OPTEE_FFA_BLOCKING_CALL(2)
>
> diff --git a/drivers/tee/optee/optee_private.h b/drivers/tee/optee/optee_private.h
> index 424898cdc4e9..dc0f355ef72a 100644
> --- a/drivers/tee/optee/optee_private.h
> +++ b/drivers/tee/optee/optee_private.h
> @@ -7,7 +7,9 @@
>  #define OPTEE_PRIVATE_H
>
>  #include <linux/arm-smccc.h>
> +#include <linux/notifier.h>
>  #include <linux/rhashtable.h>
> +#include <linux/rpmb.h>
>  #include <linux/semaphore.h>
>  #include <linux/tee_core.h>
>  #include <linux/types.h>
> @@ -20,6 +22,7 @@
>  /* Some Global Platform error codes used in this driver */
>  #define TEEC_SUCCESS                   0x00000000
>  #define TEEC_ERROR_BAD_PARAMETERS      0xFFFF0006
> +#define TEEC_ERROR_ITEM_NOT_FOUND      0xFFFF0008
>  #define TEEC_ERROR_NOT_SUPPORTED       0xFFFF000A
>  #define TEEC_ERROR_COMMUNICATION       0xFFFF000E
>  #define TEEC_ERROR_OUT_OF_MEMORY       0xFFFF000C
> @@ -28,6 +31,7 @@
>
>  /* API Return Codes are from the GP TEE Internal Core API Specification */
>  #define TEE_ERROR_TIMEOUT              0xFFFF3001
> +#define TEE_ERROR_STORAGE_NOT_AVAILABLE        0xF0100003
>
>  #define TEEC_ORIGIN_COMMS              0x00000002
>
> @@ -200,6 +204,12 @@ struct optee_ops {
>   * @notif:             notification synchronization struct
>   * @supp:              supplicant synchronization struct for RPC to supplicant
>   * @pool:              shared memory pool
> + * @mutex:             mutex protecting @rpmb_dev
> + * @rpmb_dev:          current RPMB device or NULL
> + * @rpmb_scan_bus_done flag if device registation of RPMB dependent devices
> + *                     was already done
> + * @rpmb_scan_bus_work workq to for an RPMB device and to scan optee bus
> + *                     and register RPMB dependent optee drivers
>   * @rpc_param_count:   If > 0 number of RPC parameters to make room for
>   * @scan_bus_done      flag if device registation was already done.
>   * @scan_bus_work      workq to scan optee bus and register optee drivers
> @@ -218,9 +228,16 @@ struct optee {
>         struct optee_notif notif;
>         struct optee_supp supp;
>         struct tee_shm_pool *pool;
> +       /* Protects rpmb_dev pointer */
> +       struct mutex rpmb_dev_mutex;
> +       struct rpmb_dev *rpmb_dev;
> +       struct notifier_block rpmb_intf;
>         unsigned int rpc_param_count;
> -       bool   scan_bus_done;
> +       bool scan_bus_done;
> +       bool rpmb_scan_bus_done;
> +       bool in_kernel_rpmb_routing;
>         struct work_struct scan_bus_work;
> +       struct work_struct rpmb_scan_bus_work;
>  };
>
>  struct optee_session {
> @@ -253,6 +270,8 @@ struct optee_call_ctx {
>         size_t num_entries;
>  };
>
> +extern struct blocking_notifier_head optee_rpmb_intf_added;
> +
>  int optee_notif_init(struct optee *optee, u_int max_key);
>  void optee_notif_uninit(struct optee *optee);
>  int optee_notif_wait(struct optee *optee, u_int key, u32 timeout);
> @@ -283,9 +302,14 @@ int optee_cancel_req(struct tee_context *ctx, u32 cancel_id, u32 session);
>
>  #define PTA_CMD_GET_DEVICES            0x0
>  #define PTA_CMD_GET_DEVICES_SUPP       0x1
> +#define PTA_CMD_GET_DEVICES_RPMB       0x2
>  int optee_enumerate_devices(u32 func);
>  void optee_unregister_devices(void);
> +void optee_bus_scan_rpmb(struct work_struct *work);
> +int optee_rpmb_intf_rdev(struct notifier_block *intf, unsigned long action,
> +                        void *data);
>
> +void optee_set_dev_group(struct optee *optee);
>  void optee_remove_common(struct optee *optee);
>  int optee_open(struct tee_context *ctx, bool cap_memref_null);
>  void optee_release(struct tee_context *ctx);
> diff --git a/drivers/tee/optee/optee_rpc_cmd.h b/drivers/tee/optee/optee_rpc_cmd.h
> index 4576751b490c..87a59cc03480 100644
> --- a/drivers/tee/optee/optee_rpc_cmd.h
> +++ b/drivers/tee/optee/optee_rpc_cmd.h
> @@ -104,4 +104,39 @@
>  /* I2C master control flags */
>  #define OPTEE_RPC_I2C_FLAGS_TEN_BIT    BIT(0)
>
> +/*
> + * Reset RPMB probing
> + *
> + * Releases an eventually already used RPMB devices and starts over searching
> + * for RPMB devices. Returns the kind of shared memory to use in subsequent
> + * OPTEE_RPC_CMD_RPMB_PROBE_NEXT and OPTEE_RPC_CMD_RPMB calls.
> + *
> + * [out]    value[0].a     OPTEE_RPC_SHM_TYPE_*, the parameter for
> + *                         OPTEE_RPC_CMD_SHM_ALLOC
> + */
> +#define OPTEE_RPC_CMD_RPMB_PROBE_RESET 22
> +
> +/*
> + * Probe next RPMB device
> + *
> + * [out]    value[0].a     Type of RPMB device, OPTEE_RPC_RPMB_*
> + * [out]    value[0].b     EXT CSD-slice 168 "RPMB Size"
> + * [out]    value[0].c     EXT CSD-slice 222 "Reliable Write Sector Count"
> + * [out]    memref[1]       Buffer with the raw CID
> + */
> +#define OPTEE_RPC_CMD_RPMB_PROBE_NEXT  23
> +
> +/* Type of RPMB device */
> +#define OPTEE_RPC_RPMB_EMMC            0
> +#define OPTEE_RPC_RPMB_UFS             1
> +#define OPTEE_RPC_RPMB_NVME            2
> +
> +/*
> + * Replay Protected Memory Block access
> + *
> + * [in]     memref[0]      Frames to device
> + * [out]    memref[1]      Frames from device
> + */
> +#define OPTEE_RPC_CMD_RPMB_FRAMES      24
> +
>  #endif /*__OPTEE_RPC_CMD_H*/
> diff --git a/drivers/tee/optee/optee_smc.h b/drivers/tee/optee/optee_smc.h
> index 7d9fa426505b..879426300821 100644
> --- a/drivers/tee/optee/optee_smc.h
> +++ b/drivers/tee/optee/optee_smc.h
> @@ -278,6 +278,8 @@ struct optee_smc_get_shm_config_result {
>  #define OPTEE_SMC_SEC_CAP_ASYNC_NOTIF          BIT(5)
>  /* Secure world supports pre-allocating RPC arg struct */
>  #define OPTEE_SMC_SEC_CAP_RPC_ARG              BIT(6)
> +/* Secure world supports probing for RPMB device if needed */
> +#define OPTEE_SMC_SEC_CAP_RPMB_PROBE           BIT(7)
>
>  #define OPTEE_SMC_FUNCID_EXCHANGE_CAPABILITIES 9
>  #define OPTEE_SMC_EXCHANGE_CAPABILITIES \
> diff --git a/drivers/tee/optee/rpc.c b/drivers/tee/optee/rpc.c
> index 5de4504665be..a4b49fd1d46d 100644
> --- a/drivers/tee/optee/rpc.c
> +++ b/drivers/tee/optee/rpc.c
> @@ -7,6 +7,7 @@
>
>  #include <linux/delay.h>
>  #include <linux/i2c.h>
> +#include <linux/rpmb.h>
>  #include <linux/slab.h>
>  #include <linux/tee_core.h>
>  #include "optee_private.h"
> @@ -261,6 +262,154 @@ void optee_rpc_cmd_free_suppl(struct tee_context *ctx, struct tee_shm *shm)
>         optee_supp_thrd_req(ctx, OPTEE_RPC_CMD_SHM_FREE, 1, &param);
>  }
>
> +static void handle_rpc_func_rpmb_probe_reset(struct tee_context *ctx,
> +                                            struct optee *optee,
> +                                            struct optee_msg_arg *arg)
> +{
> +       struct tee_param params[1];
> +
> +       if (arg->num_params != ARRAY_SIZE(params) ||
> +           optee->ops->from_msg_param(optee, params, arg->num_params,
> +                                      arg->params) ||
> +           params[0].attr != TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_OUTPUT) {
> +               arg->ret = TEEC_ERROR_BAD_PARAMETERS;
> +               return;
> +       }
> +
> +       params[0].u.value.a = OPTEE_RPC_SHM_TYPE_KERNEL;
> +       params[0].u.value.b = 0;
> +       params[0].u.value.c = 0;
> +       if (optee->ops->to_msg_param(optee, arg->params,
> +                                    arg->num_params, params)) {
> +               arg->ret = TEEC_ERROR_BAD_PARAMETERS;
> +               return;
> +       }
> +
> +       mutex_lock(&optee->rpmb_dev_mutex);
> +       rpmb_dev_put(optee->rpmb_dev);
> +       optee->rpmb_dev = NULL;
> +       mutex_unlock(&optee->rpmb_dev_mutex);
> +
> +       arg->ret = TEEC_SUCCESS;
> +}
> +
> +static int rpmb_type_to_rpc_type(enum rpmb_type rtype)
> +{
> +       switch (rtype) {
> +       case RPMB_TYPE_EMMC:
> +               return OPTEE_RPC_RPMB_EMMC;
> +       case RPMB_TYPE_UFS:
> +               return OPTEE_RPC_RPMB_UFS;
> +       case RPMB_TYPE_NVME:
> +               return OPTEE_RPC_RPMB_NVME;
> +       default:
> +               return -1;
> +       }
> +}
> +
> +static int rpc_rpmb_match(struct device *dev, const void *data)
> +{
> +       struct rpmb_dev *rdev = to_rpmb_dev(dev);
> +
> +       return rpmb_type_to_rpc_type(rdev->descr.type) >= 0;
> +}
> +
> +static void handle_rpc_func_rpmb_probe_next(struct tee_context *ctx,
> +                                           struct optee *optee,
> +                                           struct optee_msg_arg *arg)
> +{
> +       struct rpmb_dev *rdev;
> +       struct tee_param params[2];
> +       void *buf;
> +
> +       if (arg->num_params != ARRAY_SIZE(params) ||
> +           optee->ops->from_msg_param(optee, params, arg->num_params,
> +                                      arg->params) ||
> +           params[0].attr != TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_OUTPUT ||
> +           params[1].attr != TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_OUTPUT) {
> +               arg->ret = TEEC_ERROR_BAD_PARAMETERS;
> +               return;
> +       }
> +       buf = tee_shm_get_va(params[1].u.memref.shm,
> +                            params[1].u.memref.shm_offs);
> +       if (!buf) {
> +               arg->ret = TEEC_ERROR_BAD_PARAMETERS;
> +               return;
> +       }
> +
> +       mutex_lock(&optee->rpmb_dev_mutex);
> +       rdev = rpmb_dev_find_device(NULL, optee->rpmb_dev, rpc_rpmb_match);
> +       rpmb_dev_put(optee->rpmb_dev);
> +       optee->rpmb_dev = rdev;
> +       mutex_unlock(&optee->rpmb_dev_mutex);
> +
> +       if (!rdev) {
> +               arg->ret = TEEC_ERROR_ITEM_NOT_FOUND;
> +               return;
> +       }
> +
> +       if (params[1].u.memref.size < rdev->descr.dev_id_len) {
> +               arg->ret = TEEC_ERROR_SHORT_BUFFER;
> +               return;
> +       }
> +       memcpy(buf, rdev->descr.dev_id, rdev->descr.dev_id_len);
> +       params[1].u.memref.size = rdev->descr.dev_id_len;
> +       params[0].u.value.a = rpmb_type_to_rpc_type(rdev->descr.type);
> +       params[0].u.value.b = rdev->descr.capacity;
> +       params[0].u.value.c = rdev->descr.reliable_wr_count;
> +       if (optee->ops->to_msg_param(optee, arg->params,
> +                                    arg->num_params, params)) {
> +               arg->ret = TEEC_ERROR_BAD_PARAMETERS;
> +               return;
> +       }
> +
> +       arg->ret = TEEC_SUCCESS;
> +}
> +
> +static void handle_rpc_func_rpmb_frames(struct tee_context *ctx,
> +                                       struct optee *optee,
> +                                       struct optee_msg_arg *arg)
> +{
> +       struct tee_param params[2];
> +       struct rpmb_dev *rdev;
> +       void *p0, *p1;
> +
> +       mutex_lock(&optee->rpmb_dev_mutex);
> +       rdev = rpmb_dev_get(optee->rpmb_dev);
> +       mutex_unlock(&optee->rpmb_dev_mutex);
> +       if (!rdev) {
> +               arg->ret = TEEC_ERROR_ITEM_NOT_FOUND;
> +               return;
> +       }
> +
> +       if (arg->num_params != ARRAY_SIZE(params) ||
> +           optee->ops->from_msg_param(optee, params, arg->num_params,
> +                                      arg->params) ||
> +           params[0].attr != TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INPUT ||
> +           params[1].attr != TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_OUTPUT) {
> +               arg->ret = TEEC_ERROR_BAD_PARAMETERS;
> +               goto out;
> +       }
> +
> +       p0 = tee_shm_get_va(params[0].u.memref.shm,
> +                           params[0].u.memref.shm_offs);
> +       p1 = tee_shm_get_va(params[1].u.memref.shm,
> +                           params[1].u.memref.shm_offs);
> +       if (rpmb_route_frames(rdev, p0, params[0].u.memref.size, p1,
> +                             params[1].u.memref.size)) {
> +               arg->ret = TEEC_ERROR_BAD_PARAMETERS;
> +               goto out;
> +       }
> +       if (optee->ops->to_msg_param(optee, arg->params,
> +                                    arg->num_params, params)) {
> +               arg->ret = TEEC_ERROR_BAD_PARAMETERS;
> +               goto out;
> +       }
> +       arg->ret = TEEC_SUCCESS;
> +out:
> +       rpmb_dev_put(rdev);
> +}
> +
>  void optee_rpc_cmd(struct tee_context *ctx, struct optee *optee,
>                    struct optee_msg_arg *arg)
>  {
> @@ -277,6 +426,34 @@ void optee_rpc_cmd(struct tee_context *ctx, struct optee *optee,
>         case OPTEE_RPC_CMD_I2C_TRANSFER:
>                 handle_rpc_func_cmd_i2c_transfer(ctx, arg);
>                 break;
> +       /*
> +        * optee->in_kernel_rpmb_routing true means that OP-TEE supports
> +        * in-kernel RPMB routing _and_ that the RPMB subsystem is
> +        * reachable. This is reported to user space with
> +        * rpmb_routing_model=kernel in sysfs.
> +        *
> +        * rpmb_routing_model=kernel is also a promise to user space that
> +        * RPMB access will not require supplicant support, hence the
> +        * checks below.

Okay.

-Sumit

> +        */
> +       case OPTEE_RPC_CMD_RPMB_PROBE_RESET:
> +               if (optee->in_kernel_rpmb_routing)
> +                       handle_rpc_func_rpmb_probe_reset(ctx, optee, arg);
> +               else
> +                       handle_rpc_supp_cmd(ctx, optee, arg);
> +               break;
> +       case OPTEE_RPC_CMD_RPMB_PROBE_NEXT:
> +               if (optee->in_kernel_rpmb_routing)
> +                       handle_rpc_func_rpmb_probe_next(ctx, optee, arg);
> +               else
> +                       handle_rpc_supp_cmd(ctx, optee, arg);
> +               break;
> +       case OPTEE_RPC_CMD_RPMB_FRAMES:
> +               if (optee->in_kernel_rpmb_routing)
> +                       handle_rpc_func_rpmb_frames(ctx, optee, arg);
> +               else
> +                       handle_rpc_supp_cmd(ctx, optee, arg);
> +               break;
>         default:
>                 handle_rpc_supp_cmd(ctx, optee, arg);
>         }
> diff --git a/drivers/tee/optee/smc_abi.c b/drivers/tee/optee/smc_abi.c
> index 844285d4f03c..e9456e3e74cc 100644
> --- a/drivers/tee/optee/smc_abi.c
> +++ b/drivers/tee/optee/smc_abi.c
> @@ -20,6 +20,7 @@
>  #include <linux/of_irq.h>
>  #include <linux/of_platform.h>
>  #include <linux/platform_device.h>
> +#include <linux/rpmb.h>
>  #include <linux/sched.h>
>  #include <linux/slab.h>
>  #include <linux/string.h>
> @@ -1685,6 +1686,10 @@ static int optee_probe(struct platform_device *pdev)
>         optee->smc.sec_caps = sec_caps;
>         optee->rpc_param_count = rpc_param_count;
>
> +       if (IS_REACHABLE(CONFIG_RPMB) &&
> +           (sec_caps & OPTEE_SMC_SEC_CAP_RPMB_PROBE))
> +               optee->in_kernel_rpmb_routing = true;
> +
>         teedev = tee_device_alloc(&optee_clnt_desc, NULL, pool, optee);
>         if (IS_ERR(teedev)) {
>                 rc = PTR_ERR(teedev);
> @@ -1699,6 +1704,8 @@ static int optee_probe(struct platform_device *pdev)
>         }
>         optee->supp_teedev = teedev;
>
> +       optee_set_dev_group(optee);
> +
>         rc = tee_device_register(optee->teedev);
>         if (rc)
>                 goto err_unreg_supp_teedev;
> @@ -1712,6 +1719,7 @@ static int optee_probe(struct platform_device *pdev)
>         optee->smc.memremaped_shm = memremaped_shm;
>         optee->pool = pool;
>         optee_shm_arg_cache_init(optee, arg_cache_flags);
> +       mutex_init(&optee->rpmb_dev_mutex);
>
>         platform_set_drvdata(pdev, optee);
>         ctx = teedev_open(optee->teedev);
> @@ -1766,6 +1774,10 @@ static int optee_probe(struct platform_device *pdev)
>         if (rc)
>                 goto err_disable_shm_cache;
>
> +       INIT_WORK(&optee->rpmb_scan_bus_work, optee_bus_scan_rpmb);
> +       optee->rpmb_intf.notifier_call = optee_rpmb_intf_rdev;
> +       blocking_notifier_chain_register(&optee_rpmb_intf_added,
> +                                        &optee->rpmb_intf);
>         pr_info("initialized driver\n");
>         return 0;
>
> @@ -1779,6 +1791,8 @@ static int optee_probe(struct platform_device *pdev)
>  err_close_ctx:
>         teedev_close_context(ctx);
>  err_supp_uninit:
> +       rpmb_dev_put(optee->rpmb_dev);
> +       mutex_destroy(&optee->rpmb_dev_mutex);
>         optee_shm_arg_cache_uninit(optee);
>         optee_supp_uninit(&optee->supp);
>         mutex_destroy(&optee->call_queue.mutex);
> --
> 2.34.1
>