Enable userspace to allocate shared memory with QTEE. Since QTEE handles shared memory as object, a wrapper is implemented to represent tee_shm as an object. The shared memory identifier, obtained through TEE_IOC_SHM_ALLOC, is transferred to the driver using TEE_IOCTL_PARAM_ATTR_TYPE_OBJREF_INPUT/OUTPUT.
Signed-off-by: Amirreza Zarrabi amirreza.zarrabi@oss.qualcomm.com --- drivers/tee/qcomtee/Makefile | 1 + drivers/tee/qcomtee/call.c | 10 +- drivers/tee/qcomtee/mem_obj.c | 172 ++++++++++++++++++++++++++++++++++ drivers/tee/qcomtee/primordial_obj.c | 50 ++++++++++ drivers/tee/qcomtee/qcomtee_private.h | 39 ++++++++ drivers/tee/qcomtee/shm.c | 3 - 6 files changed, 270 insertions(+), 5 deletions(-)
diff --git a/drivers/tee/qcomtee/Makefile b/drivers/tee/qcomtee/Makefile index a3a2d00e83f0..6cb9fd38dc67 100644 --- a/drivers/tee/qcomtee/Makefile +++ b/drivers/tee/qcomtee/Makefile @@ -3,6 +3,7 @@ obj-$(CONFIG_QCOMTEE) += qcomtee.o qcomtee-objs += async.o qcomtee-objs += call.o qcomtee-objs += core.o +qcomtee-objs += mem_obj.o qcomtee-objs += primordial_obj.o qcomtee-objs += qcom_scm.o qcomtee-objs += release.o diff --git a/drivers/tee/qcomtee/call.c b/drivers/tee/qcomtee/call.c index 9e288723ec21..239ffc24476a 100644 --- a/drivers/tee/qcomtee/call.c +++ b/drivers/tee/qcomtee/call.c @@ -110,8 +110,8 @@ void qcomtee_context_del_qtee_object(struct tee_param *param, * &enum qcomtee_arg_type value. It gets the object's refcount in @arg; * the caller should manage to put it afterward. * - * For user objects (i.e. (param->u.objref.flags & QCOMTEE_OBJREF_FLAG_USER)), - * qcomtee_user_param_to_object() calls qcomtee_object_get() to keep a + * For non-QTEE objects (i.e. !(param->u.objref.flags & + * QCOMTEE_OBJREF_FLAG_TEE)), qcomtee_object_get() is called to keep a * temporary copy for the driver as the release of objects are asynchronous * and they may go away even before returning from the invocation. * @@ -135,6 +135,9 @@ int qcomtee_objref_to_arg(struct qcomtee_arg *arg, struct tee_param *param, /* param is a QTEE object: */ } else if (param->u.objref.flags & QCOMTEE_OBJREF_FLAG_TEE) { err = qcomtee_context_find_qtee_object(&arg->o, param, ctx); + /* param is a memory object: */ + } else if (param->u.objref.flags & QCOMTEE_OBJREF_FLAG_MEM) { + err = qcomtee_memobj_param_to_object(&arg->o, param, ctx); } else { err = -EINVAL; } @@ -181,6 +184,9 @@ int qcomtee_objref_from_arg(struct tee_param *param, struct qcomtee_arg *arg, if (is_qcomtee_user_object(object)) err = qcomtee_user_param_from_object(param, object, ctx); + else if (is_qcomtee_memobj_object(object)) + err = qcomtee_memobj_param_from_object(param, object, + ctx); else err = -EINVAL;
diff --git a/drivers/tee/qcomtee/mem_obj.c b/drivers/tee/qcomtee/mem_obj.c new file mode 100644 index 000000000000..e17eb3b3dc2e --- /dev/null +++ b/drivers/tee/qcomtee/mem_obj.c @@ -0,0 +1,172 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (c) 2025 Qualcomm Innovation Center, Inc. All rights reserved. + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <linux/mm.h> +#include <linux/firmware/qcom/qcom_scm.h> + +#include "qcomtee_private.h" + +/** + * DOC: Memory and Mapping Objects + * + * QTEE uses memory objects for memory sharing with Linux. + * A memory object can be a standard dma_buf or a contiguous memory range, + * e.g., tee_shm. A memory object should support one operation: map. When + * invoked by QTEE, a mapping object is generated. A mapping object supports + * one operation: unmap. + * + * (1) To map a memory object, QTEE invokes the primordial object with + * %QCOMTEE_OBJECT_OP_MAP_REGION operation; see + * qcomtee_primordial_obj_dispatch(). + * (2) To unmap a memory object, QTEE releases the mapping object which + * calls qcomtee_mem_object_release(). + * + * The map operation is implemented in the primordial object as a privileged + * operation instead of qcomtee_mem_object_dispatch(). Otherwise, on + * platforms without shm_bridge, a user can trick QTEE into writing to the + * kernel memory by passing a user object as a memory object and returning a + * random physical address as the result of the mapping request. + */ + +struct qcomtee_mem_object { + struct qcomtee_object object; + struct tee_shm *shm; + /* QTEE requires these felids to be page aligned. */ + phys_addr_t paddr; /* Physical address of range. */ + size_t size; /* Size of the range. */ +}; + +#define to_qcomtee_mem_object(o) \ + container_of((o), struct qcomtee_mem_object, object) + +static struct qcomtee_object_operations qcomtee_mem_object_ops; + +/* Is it a memory object using tee_shm? */ +int is_qcomtee_memobj_object(struct qcomtee_object *object) +{ + return object != NULL_QCOMTEE_OBJECT && + typeof_qcomtee_object(object) == QCOMTEE_OBJECT_TYPE_CB && + object->ops == &qcomtee_mem_object_ops; +} + +static int qcomtee_mem_object_dispatch(struct qcomtee_object_invoke_ctx *oic, + struct qcomtee_object *object, u32 op, + struct qcomtee_arg *args) +{ + return -EINVAL; +} + +static void qcomtee_mem_object_release(struct qcomtee_object *object) +{ + struct qcomtee_mem_object *mem_object = to_qcomtee_mem_object(object); + + /* Matching get is in qcomtee_memobj_param_to_object(). */ + tee_shm_put(mem_object->shm); + kfree(mem_object); +} + +static struct qcomtee_object_operations qcomtee_mem_object_ops = { + .release = qcomtee_mem_object_release, + .dispatch = qcomtee_mem_object_dispatch, +}; + +/** + * qcomtee_memobj_param_to_object() - OBJREF parameter to &struct qcomtee_object. + * @object: object returned. + * @param: TEE parameter. + * @ctx: context in which the conversion should happen. + * + * @param is an OBJREF with %QCOMTEE_OBJREF_FLAG_MEM flags. + * It calls qcomtee_object_get() to keep a copy of @object for the driver + * as well as a copy for QTEE. + * + * Return: On success return 0 or <0 on failure. + */ +int qcomtee_memobj_param_to_object(struct qcomtee_object **object, + struct tee_param *param, + struct tee_context *ctx) +{ + struct qcomtee_mem_object *mem_object __free(kfree) = NULL; + struct tee_shm *shm; + int err; + + mem_object = kzalloc(sizeof(*mem_object), GFP_KERNEL); + if (!mem_object) + return -ENOMEM; + + shm = tee_shm_get_from_id(ctx, param->u.objref.id); + if (!shm) + return -EINVAL; + + /* mem-object wrapping the memref. */ + err = qcomtee_object_user_init(&mem_object->object, + QCOMTEE_OBJECT_TYPE_CB, + &qcomtee_mem_object_ops, "tee-shm-%d", + shm->id); + if (err) { + tee_shm_put(shm); + + return err; + } + + mem_object->paddr = shm->paddr; + mem_object->size = shm->size; + mem_object->shm = shm; + + *object = &no_free_ptr(mem_object)->object; + qcomtee_object_get(*object); + + return 0; +} + +/* Reverse what qcomtee_memobj_param_to_object() does. */ +int qcomtee_memobj_param_from_object(struct tee_param *param, + struct qcomtee_object *object, + struct tee_context *ctx) +{ + struct qcomtee_mem_object *mem_object; + + mem_object = to_qcomtee_mem_object(object); + /* Sure if the memobj is in a same context it is originated from. */ + if (mem_object->shm->ctx != ctx) + return -EINVAL; + + param->u.objref.id = mem_object->shm->id; + param->u.objref.flags = QCOMTEE_OBJREF_FLAG_MEM; + + /* Passing shm->id to userspace; drop the reference. */ + qcomtee_object_put(object); + + return 0; +} + +/** + * qcomtee_mem_object_map() - Map a memory object. + * @object: memory object. + * @map_object: created mapping object. + * @mem_paddr: physical address of the memory. + * @mem_size: size of the memory. + * @perms: QTEE access permissions. + * + * Return: On success return 0 or <0 on failure. + */ +int qcomtee_mem_object_map(struct qcomtee_object *object, + struct qcomtee_object **map_object, u64 *mem_paddr, + u64 *mem_size, u32 *perms) +{ + struct qcomtee_mem_object *mem_object = to_qcomtee_mem_object(object); + + /* Reuses the memory object as a mapping object by re-sharing it. */ + qcomtee_object_get(&mem_object->object); + + *map_object = &mem_object->object; + *mem_paddr = mem_object->paddr; + *mem_size = mem_object->size; + *perms = QCOM_SCM_PERM_RW; + + return 0; +} diff --git a/drivers/tee/qcomtee/primordial_obj.c b/drivers/tee/qcomtee/primordial_obj.c index a30967d89c91..598557f09746 100644 --- a/drivers/tee/qcomtee/primordial_obj.c +++ b/drivers/tee/qcomtee/primordial_obj.c @@ -16,18 +16,31 @@ * for native kernel services or privileged operations. * * We support: + * - %QCOMTEE_OBJECT_OP_MAP_REGION to map a memory object and return mapping + * object and mapping information (see qcomtee_mem_object_map()). * - %QCOMTEE_OBJECT_OP_YIELD to yield by the thread running in QTEE. * - %QCOMTEE_OBJECT_OP_SLEEP to wait for a period of time. */
+#define QCOMTEE_OBJECT_OP_MAP_REGION 0 #define QCOMTEE_OBJECT_OP_YIELD 1 #define QCOMTEE_OBJECT_OP_SLEEP 2
+/* Mapping information format as expected by QTEE. */ +struct qcomtee_mapping_info { + u64 paddr; + u64 len; + u32 perms; +} __packed; + static int qcomtee_primordial_obj_dispatch(struct qcomtee_object_invoke_ctx *oic, struct qcomtee_object *primordial_object_unused, u32 op, struct qcomtee_arg *args) { + struct qcomtee_mapping_info *map_info; + struct qcomtee_object *mem_object; + struct qcomtee_object *map_object; int err = 0;
switch (op) { @@ -35,6 +48,7 @@ qcomtee_primordial_obj_dispatch(struct qcomtee_object_invoke_ctx *oic, cond_resched(); /* No output object. */ oic->data = NULL; + break; case QCOMTEE_OBJECT_OP_SLEEP: /* Check message format matched QCOMTEE_OBJECT_OP_SLEEP op. */ @@ -46,6 +60,29 @@ qcomtee_primordial_obj_dispatch(struct qcomtee_object_invoke_ctx *oic, msleep(*(u32 *)(args[0].b.addr)); /* No output object. */ oic->data = NULL; + + break; + case QCOMTEE_OBJECT_OP_MAP_REGION: + if (qcomtee_args_len(args) != 3 || + args[0].type != QCOMTEE_ARG_TYPE_OB || + args[1].type != QCOMTEE_ARG_TYPE_IO || + args[2].type != QCOMTEE_ARG_TYPE_OO || + args[0].b.size < sizeof(struct qcomtee_mapping_info)) + return -EINVAL; + + map_info = args[0].b.addr; + mem_object = args[1].o; + + qcomtee_mem_object_map(mem_object, &map_object, + &map_info->paddr, &map_info->len, + &map_info->perms); + + args[2].o = map_object; + /* One output object; pass it for cleanup to notify. */ + oic->data = map_object; + + qcomtee_object_put(mem_object); + break; default: err = -EINVAL; @@ -54,8 +91,21 @@ qcomtee_primordial_obj_dispatch(struct qcomtee_object_invoke_ctx *oic, return err; }
+/* Called after submitting the callback response. */ +static void qcomtee_primordial_obj_notify(struct qcomtee_object_invoke_ctx *oic, + struct qcomtee_object *unused, + int err) +{ + struct qcomtee_object *object = oic->data; + + /* If err, QTEE did not obtain mapping object. Drop it. */ + if (object && err) + qcomtee_object_put(object); +} + static struct qcomtee_object_operations qcomtee_primordial_obj_ops = { .dispatch = qcomtee_primordial_obj_dispatch, + .notify = qcomtee_primordial_obj_notify, };
struct qcomtee_object qcomtee_primordial_object = { diff --git a/drivers/tee/qcomtee/qcomtee_private.h b/drivers/tee/qcomtee/qcomtee_private.h index e59cfb3b79dd..a70052803399 100644 --- a/drivers/tee/qcomtee/qcomtee_private.h +++ b/drivers/tee/qcomtee/qcomtee_private.h @@ -15,6 +15,7 @@ /* Flags relating to object reference. */ #define QCOMTEE_OBJREF_FLAG_TEE BIT(0) #define QCOMTEE_OBJREF_FLAG_USER BIT(1) +#define QCOMTEE_OBJREF_FLAG_MEM BIT(2)
/** * struct qcomtee - Main service struct. @@ -222,4 +223,42 @@ int qcomtee_user_object_submit(struct tee_context *ctx, /* (2) Primordial Object. */ extern struct qcomtee_object qcomtee_primordial_object;
+/* (3) Memory Object API. */ + +/* Is it a memory object using tee_shm? */ +int is_qcomtee_memobj_object(struct qcomtee_object *object); + +/** + * qcomtee_memobj_param_to_object() - OBJREF parameter to &struct qcomtee_object. + * @object: object returned. + * @param: TEE parameter. + * @ctx: context in which the conversion should happen. + * + * @param is an OBJREF with %QCOMTEE_OBJREF_FLAG_MEM flags. + * + * Return: On success return 0 or <0 on failure. + */ +int qcomtee_memobj_param_to_object(struct qcomtee_object **object, + struct tee_param *param, + struct tee_context *ctx); + +/* Reverse what qcomtee_memobj_param_to_object() does. */ +int qcomtee_memobj_param_from_object(struct tee_param *param, + struct qcomtee_object *object, + struct tee_context *ctx); + +/** + * qcomtee_mem_object_map() - Map a memory object. + * @object: memory object. + * @map_object: created mapping object. + * @mem_paddr: physical address of the memory. + * @mem_size: size of the memory. + * @perms: QTEE access permissions. + * + * Return: On success return 0 or <0 on failure. + */ +int qcomtee_mem_object_map(struct qcomtee_object *object, + struct qcomtee_object **map_object, u64 *mem_paddr, + u64 *mem_size, u32 *perms); + #endif /* QCOMTEE_PRIVATE_H */ diff --git a/drivers/tee/qcomtee/shm.c b/drivers/tee/qcomtee/shm.c index 998aabe96434..9bdf9e48bfeb 100644 --- a/drivers/tee/qcomtee/shm.c +++ b/drivers/tee/qcomtee/shm.c @@ -113,9 +113,6 @@ static int qcomtee_shm_unregister(struct tee_context *ctx, struct tee_shm *shm) static int pool_op_alloc(struct tee_shm_pool *pool, struct tee_shm *shm, size_t size, size_t align) { - if (!(shm->flags & TEE_SHM_PRIV)) - return -ENOMEM; - return tee_dyn_shm_alloc_helper(shm, size, align, qcomtee_shm_register); }