| Message ID | 1548309279-5281-2-git-send-email-sumit.garg@linaro.org |
|---|---|
| State | Accepted |
| Commit | 0fc1db9d105915021260eb241661b8e96f5c0f1a |
| Headers | show |
| Series | Introduce TEE bus driver framework | expand |
On Thu, 24 Jan 2019 at 15:15, Daniel Thompson <daniel.thompson@linaro.org> wrote: > > On Thu, Jan 24, 2019 at 11:24:36AM +0530, Sumit Garg wrote: > > Introduce a generic TEE bus driver concept for TEE based kernel drivers > > which would like to communicate with TEE based devices/services. Also > > add support in module device table for these new TEE based devices. > > > > In this TEE bus concept, devices/services are identified via Universally > > Unique Identifier (UUID) and drivers register a table of device UUIDs > > which they can support. > > > > So this TEE bus framework registers following apis: > > - match(): Iterates over the driver UUID table to find a corresponding > > match for device UUID. If a match is found, then this particular device > > is probed via corresponding probe api registered by the driver. This > > process happens whenever a device or a driver is registered with TEE > > bus. > > - uevent(): Notifies user-space (udev) whenever a new device is registered > > on this bus for auto-loading of out-of-tree drivers. > > out-of-tree? Surely it can be used to auto-load any modulized driver. > Agree, will correct. > > > Also this framework allows for device enumeration to be specific to > > corresponding TEE implementation like OP-TEE etc. > > > > Signed-off-by: Sumit Garg <sumit.garg@linaro.org> > > --- > > drivers/tee/tee_core.c | 57 ++++++++++++++++++++++++++++++++++++--- > > include/linux/mod_devicetable.h | 9 +++++++ > > include/linux/tee_drv.h | 32 +++++++++++++++++++++- > > scripts/mod/devicetable-offsets.c | 3 +++ > > scripts/mod/file2alias.c | 19 +++++++++++++ > > 5 files changed, 115 insertions(+), 5 deletions(-) > > > > diff --git a/drivers/tee/tee_core.c b/drivers/tee/tee_core.c > > index 7b2bb4c..9f4c8bc 100644 > > --- a/drivers/tee/tee_core.c > > +++ b/drivers/tee/tee_core.c > > @@ -15,7 +15,6 @@ > > #define pr_fmt(fmt) "%s: " fmt, __func__ > > > > #include <linux/cdev.h> > > -#include <linux/device.h> > > #include <linux/fs.h> > > #include <linux/idr.h> > > #include <linux/module.h> > > @@ -1027,6 +1026,42 @@ int tee_client_invoke_func(struct tee_context *ctx, > > } > > EXPORT_SYMBOL_GPL(tee_client_invoke_func); > > > > +static int tee_client_device_match(struct device *dev, > > + struct device_driver *drv) > > +{ > > + const struct tee_client_device_id *id_table; > > + struct tee_client_device *tee_device; > > + > > + id_table = to_tee_client_driver(drv)->id_table; > > + tee_device = to_tee_client_device(dev); > > + > > + while (!uuid_is_null(&id_table->uuid)) { > > + if (uuid_equal(&tee_device->id.uuid, &id_table->uuid)) > > + return 1; > > + id_table++; > > + } > > + > > + return 0; > > +} > > + > > +static int tee_client_device_uevent(struct device *dev, > > + struct kobj_uevent_env *env) > > +{ > > + uuid_t *dev_id = &to_tee_client_device(dev)->id.uuid; > > + > > + if (add_uevent_var(env, "MODALIAS=tee:%pUb", dev_id)) > > + return -ENOMEM; > > + > > + return 0; > > Can just return directly here: > > return add_uevent_var(... ) Okay will use this instead. > > Other than these nitpicks then FWIW: > Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org> > Thanks. -Sumit > > +} > > + > > +struct bus_type tee_bus_type = { > > + .name = "tee", > > + .match = tee_client_device_match, > > + .uevent = tee_client_device_uevent, > > +}; > > +EXPORT_SYMBOL_GPL(tee_bus_type); > > + > > static int __init tee_init(void) > > { > > int rc; > > @@ -1040,18 +1075,32 @@ static int __init tee_init(void) > > rc = alloc_chrdev_region(&tee_devt, 0, TEE_NUM_DEVICES, "tee"); > > if (rc) { > > pr_err("failed to allocate char dev region\n"); > > - class_destroy(tee_class); > > - tee_class = NULL; > > + goto out_unreg_class; > > } > > > > + rc = bus_register(&tee_bus_type); > > + if (rc) { > > + pr_err("failed to register tee bus\n"); > > + goto out_unreg_chrdev; > > + } > > + > > + return 0; > > + > > +out_unreg_chrdev: > > + unregister_chrdev_region(tee_devt, TEE_NUM_DEVICES); > > +out_unreg_class: > > + class_destroy(tee_class); > > + tee_class = NULL; > > + > > return rc; > > } > > > > static void __exit tee_exit(void) > > { > > + bus_unregister(&tee_bus_type); > > + unregister_chrdev_region(tee_devt, TEE_NUM_DEVICES); > > class_destroy(tee_class); > > tee_class = NULL; > > - unregister_chrdev_region(tee_devt, TEE_NUM_DEVICES); > > } > > > > subsys_initcall(tee_init); > > diff --git a/include/linux/mod_devicetable.h b/include/linux/mod_devicetable.h > > index f9bd2f3..14eaeeb 100644 > > --- a/include/linux/mod_devicetable.h > > +++ b/include/linux/mod_devicetable.h > > @@ -779,4 +779,13 @@ struct typec_device_id { > > kernel_ulong_t driver_data; > > }; > > > > +/** > > + * struct tee_client_device_id - tee based device identifier > > + * @uuid: For TEE based client devices we use the device uuid as > > + * the identifier. > > + */ > > +struct tee_client_device_id { > > + uuid_t uuid; > > +}; > > + > > #endif /* LINUX_MOD_DEVICETABLE_H */ > > diff --git a/include/linux/tee_drv.h b/include/linux/tee_drv.h > > index 6cfe058..ce957ce 100644 > > --- a/include/linux/tee_drv.h > > +++ b/include/linux/tee_drv.h > > @@ -15,11 +15,14 @@ > > #ifndef __TEE_DRV_H > > #define __TEE_DRV_H > > > > -#include <linux/types.h> > > +#include <linux/device.h> > > #include <linux/idr.h> > > #include <linux/kref.h> > > #include <linux/list.h> > > +#include <linux/mod_devicetable.h> > > #include <linux/tee.h> > > +#include <linux/types.h> > > +#include <linux/uuid.h> > > > > /* > > * The file describes the API provided by the generic TEE driver to the > > @@ -538,4 +541,31 @@ static inline bool tee_param_is_memref(struct tee_param *param) > > } > > } > > > > +extern struct bus_type tee_bus_type; > > + > > +/** > > + * struct tee_client_device - tee based device > > + * @id: device identifier > > + * @dev: device structure > > + */ > > +struct tee_client_device { > > + struct tee_client_device_id id; > > + struct device dev; > > +}; > > + > > +#define to_tee_client_device(d) container_of(d, struct tee_client_device, dev) > > + > > +/** > > + * struct tee_client_driver - tee client driver > > + * @id_table: device id table supported by this driver > > + * @driver: driver structure > > + */ > > +struct tee_client_driver { > > + const struct tee_client_device_id *id_table; > > + struct device_driver driver; > > +}; > > + > > +#define to_tee_client_driver(d) \ > > + container_of(d, struct tee_client_driver, driver) > > + > > #endif /*__TEE_DRV_H*/ > > diff --git a/scripts/mod/devicetable-offsets.c b/scripts/mod/devicetable-offsets.c > > index 2930044..1607183 100644 > > --- a/scripts/mod/devicetable-offsets.c > > +++ b/scripts/mod/devicetable-offsets.c > > @@ -225,5 +225,8 @@ int main(void) > > DEVID_FIELD(typec_device_id, svid); > > DEVID_FIELD(typec_device_id, mode); > > > > + DEVID(tee_client_device_id); > > + DEVID_FIELD(tee_client_device_id, uuid); > > + > > return 0; > > } > > diff --git a/scripts/mod/file2alias.c b/scripts/mod/file2alias.c > > index a37af7d..d0e4172 100644 > > --- a/scripts/mod/file2alias.c > > +++ b/scripts/mod/file2alias.c > > @@ -37,6 +37,9 @@ typedef unsigned char __u8; > > typedef struct { > > __u8 b[16]; > > } uuid_le; > > +typedef struct { > > + __u8 b[16]; > > +} uuid_t; > > > > /* Big exception to the "don't include kernel headers into userspace, which > > * even potentially has different endianness and word sizes, since > > @@ -1287,6 +1290,21 @@ static int do_typec_entry(const char *filename, void *symval, char *alias) > > return 1; > > } > > > > +/* Looks like: tee:uuid */ > > +static int do_tee_entry(const char *filename, void *symval, char *alias) > > +{ > > + DEF_FIELD(symval, tee_client_device_id, uuid); > > + > > + sprintf(alias, "tee:%02x%02x%02x%02x-%02x%02x-%02x%02x-%02x%02x-%02x%02x%02x%02x%02x%02x", > > + uuid.b[0], uuid.b[1], uuid.b[2], uuid.b[3], uuid.b[4], > > + uuid.b[5], uuid.b[6], uuid.b[7], uuid.b[8], uuid.b[9], > > + uuid.b[10], uuid.b[11], uuid.b[12], uuid.b[13], uuid.b[14], > > + uuid.b[15]); > > + > > + add_wildcard(alias); > > + return 1; > > +} > > + > > /* Does namelen bytes of name exactly match the symbol? */ > > static bool sym_is(const char *name, unsigned namelen, const char *symbol) > > { > > @@ -1357,6 +1375,7 @@ static const struct devtable devtable[] = { > > {"fslmc", SIZE_fsl_mc_device_id, do_fsl_mc_entry}, > > {"tbsvc", SIZE_tb_service_id, do_tbsvc_entry}, > > {"typec", SIZE_typec_device_id, do_typec_entry}, > > + {"tee", SIZE_tee_client_device_id, do_tee_entry}, > > }; > > > > /* Create MODULE_ALIAS() statements. > > -- > > 2.7.4 > >
diff --git a/drivers/tee/tee_core.c b/drivers/tee/tee_core.c index 7b2bb4c..9f4c8bc 100644 --- a/drivers/tee/tee_core.c +++ b/drivers/tee/tee_core.c @@ -15,7 +15,6 @@ #define pr_fmt(fmt) "%s: " fmt, __func__ #include <linux/cdev.h> -#include <linux/device.h> #include <linux/fs.h> #include <linux/idr.h> #include <linux/module.h> @@ -1027,6 +1026,42 @@ int tee_client_invoke_func(struct tee_context *ctx, } EXPORT_SYMBOL_GPL(tee_client_invoke_func); +static int tee_client_device_match(struct device *dev, + struct device_driver *drv) +{ + const struct tee_client_device_id *id_table; + struct tee_client_device *tee_device; + + id_table = to_tee_client_driver(drv)->id_table; + tee_device = to_tee_client_device(dev); + + while (!uuid_is_null(&id_table->uuid)) { + if (uuid_equal(&tee_device->id.uuid, &id_table->uuid)) + return 1; + id_table++; + } + + return 0; +} + +static int tee_client_device_uevent(struct device *dev, + struct kobj_uevent_env *env) +{ + uuid_t *dev_id = &to_tee_client_device(dev)->id.uuid; + + if (add_uevent_var(env, "MODALIAS=tee:%pUb", dev_id)) + return -ENOMEM; + + return 0; +} + +struct bus_type tee_bus_type = { + .name = "tee", + .match = tee_client_device_match, + .uevent = tee_client_device_uevent, +}; +EXPORT_SYMBOL_GPL(tee_bus_type); + static int __init tee_init(void) { int rc; @@ -1040,18 +1075,32 @@ static int __init tee_init(void) rc = alloc_chrdev_region(&tee_devt, 0, TEE_NUM_DEVICES, "tee"); if (rc) { pr_err("failed to allocate char dev region\n"); - class_destroy(tee_class); - tee_class = NULL; + goto out_unreg_class; } + rc = bus_register(&tee_bus_type); + if (rc) { + pr_err("failed to register tee bus\n"); + goto out_unreg_chrdev; + } + + return 0; + +out_unreg_chrdev: + unregister_chrdev_region(tee_devt, TEE_NUM_DEVICES); +out_unreg_class: + class_destroy(tee_class); + tee_class = NULL; + return rc; } static void __exit tee_exit(void) { + bus_unregister(&tee_bus_type); + unregister_chrdev_region(tee_devt, TEE_NUM_DEVICES); class_destroy(tee_class); tee_class = NULL; - unregister_chrdev_region(tee_devt, TEE_NUM_DEVICES); } subsys_initcall(tee_init); diff --git a/include/linux/mod_devicetable.h b/include/linux/mod_devicetable.h index f9bd2f3..14eaeeb 100644 --- a/include/linux/mod_devicetable.h +++ b/include/linux/mod_devicetable.h @@ -779,4 +779,13 @@ struct typec_device_id { kernel_ulong_t driver_data; }; +/** + * struct tee_client_device_id - tee based device identifier + * @uuid: For TEE based client devices we use the device uuid as + * the identifier. + */ +struct tee_client_device_id { + uuid_t uuid; +}; + #endif /* LINUX_MOD_DEVICETABLE_H */ diff --git a/include/linux/tee_drv.h b/include/linux/tee_drv.h index 6cfe058..ce957ce 100644 --- a/include/linux/tee_drv.h +++ b/include/linux/tee_drv.h @@ -15,11 +15,14 @@ #ifndef __TEE_DRV_H #define __TEE_DRV_H -#include <linux/types.h> +#include <linux/device.h> #include <linux/idr.h> #include <linux/kref.h> #include <linux/list.h> +#include <linux/mod_devicetable.h> #include <linux/tee.h> +#include <linux/types.h> +#include <linux/uuid.h> /* * The file describes the API provided by the generic TEE driver to the @@ -538,4 +541,31 @@ static inline bool tee_param_is_memref(struct tee_param *param) } } +extern struct bus_type tee_bus_type; + +/** + * struct tee_client_device - tee based device + * @id: device identifier + * @dev: device structure + */ +struct tee_client_device { + struct tee_client_device_id id; + struct device dev; +}; + +#define to_tee_client_device(d) container_of(d, struct tee_client_device, dev) + +/** + * struct tee_client_driver - tee client driver + * @id_table: device id table supported by this driver + * @driver: driver structure + */ +struct tee_client_driver { + const struct tee_client_device_id *id_table; + struct device_driver driver; +}; + +#define to_tee_client_driver(d) \ + container_of(d, struct tee_client_driver, driver) + #endif /*__TEE_DRV_H*/ diff --git a/scripts/mod/devicetable-offsets.c b/scripts/mod/devicetable-offsets.c index 2930044..1607183 100644 --- a/scripts/mod/devicetable-offsets.c +++ b/scripts/mod/devicetable-offsets.c @@ -225,5 +225,8 @@ int main(void) DEVID_FIELD(typec_device_id, svid); DEVID_FIELD(typec_device_id, mode); + DEVID(tee_client_device_id); + DEVID_FIELD(tee_client_device_id, uuid); + return 0; } diff --git a/scripts/mod/file2alias.c b/scripts/mod/file2alias.c index a37af7d..d0e4172 100644 --- a/scripts/mod/file2alias.c +++ b/scripts/mod/file2alias.c @@ -37,6 +37,9 @@ typedef unsigned char __u8; typedef struct { __u8 b[16]; } uuid_le; +typedef struct { + __u8 b[16]; +} uuid_t; /* Big exception to the "don't include kernel headers into userspace, which * even potentially has different endianness and word sizes, since @@ -1287,6 +1290,21 @@ static int do_typec_entry(const char *filename, void *symval, char *alias) return 1; } +/* Looks like: tee:uuid */ +static int do_tee_entry(const char *filename, void *symval, char *alias) +{ + DEF_FIELD(symval, tee_client_device_id, uuid); + + sprintf(alias, "tee:%02x%02x%02x%02x-%02x%02x-%02x%02x-%02x%02x-%02x%02x%02x%02x%02x%02x", + uuid.b[0], uuid.b[1], uuid.b[2], uuid.b[3], uuid.b[4], + uuid.b[5], uuid.b[6], uuid.b[7], uuid.b[8], uuid.b[9], + uuid.b[10], uuid.b[11], uuid.b[12], uuid.b[13], uuid.b[14], + uuid.b[15]); + + add_wildcard(alias); + return 1; +} + /* Does namelen bytes of name exactly match the symbol? */ static bool sym_is(const char *name, unsigned namelen, const char *symbol) { @@ -1357,6 +1375,7 @@ static const struct devtable devtable[] = { {"fslmc", SIZE_fsl_mc_device_id, do_fsl_mc_entry}, {"tbsvc", SIZE_tb_service_id, do_tbsvc_entry}, {"typec", SIZE_typec_device_id, do_typec_entry}, + {"tee", SIZE_tee_client_device_id, do_tee_entry}, }; /* Create MODULE_ALIAS() statements.
Introduce a generic TEE bus driver concept for TEE based kernel drivers which would like to communicate with TEE based devices/services. Also add support in module device table for these new TEE based devices. In this TEE bus concept, devices/services are identified via Universally Unique Identifier (UUID) and drivers register a table of device UUIDs which they can support. So this TEE bus framework registers following apis: - match(): Iterates over the driver UUID table to find a corresponding match for device UUID. If a match is found, then this particular device is probed via corresponding probe api registered by the driver. This process happens whenever a device or a driver is registered with TEE bus. - uevent(): Notifies user-space (udev) whenever a new device is registered on this bus for auto-loading of out-of-tree drivers. Also this framework allows for device enumeration to be specific to corresponding TEE implementation like OP-TEE etc. Signed-off-by: Sumit Garg <sumit.garg@linaro.org> --- drivers/tee/tee_core.c | 57 ++++++++++++++++++++++++++++++++++++--- include/linux/mod_devicetable.h | 9 +++++++ include/linux/tee_drv.h | 32 +++++++++++++++++++++- scripts/mod/devicetable-offsets.c | 3 +++ scripts/mod/file2alias.c | 19 +++++++++++++ 5 files changed, 115 insertions(+), 5 deletions(-) -- 2.7.4