From: Jens Wiklander jens.wiklander@linaro.org
Added new ioctl to allow users register own buffers as a shared memory.
Signed-off-by: Jens Wiklander jens.wiklander@linaro.org Signed-off-by: Volodymyr Babchuk vlad.babchuk@gmail.com ---
* Removed dev_err() in cases when this is not exactly an error * tee_shm_register() return ENOTSUPP in cases when registration of memory is not supported. * Fixed nasty mistake with sizeof(struct page) instead of sizeof(struct page*) * tee_shm_is_registered() made inline. In v1 there was separate patch that did this.
--- drivers/tee/tee_core.c | 41 +++++++++- drivers/tee/tee_shm.c | 205 +++++++++++++++++++++++++++++++++++++++++------ include/linux/tee_drv.h | 47 ++++++++++- include/uapi/linux/tee.h | 30 +++++++ 4 files changed, 293 insertions(+), 30 deletions(-)
diff --git a/drivers/tee/tee_core.c b/drivers/tee/tee_core.c index 58a5009..295910f 100644 --- a/drivers/tee/tee_core.c +++ b/drivers/tee/tee_core.c @@ -114,8 +114,6 @@ static int tee_ioctl_shm_alloc(struct tee_context *ctx, if (data.flags) return -EINVAL;
- data.id = -1; - shm = tee_shm_alloc(ctx, data.size, TEE_SHM_MAPPED | TEE_SHM_DMA_BUF); if (IS_ERR(shm)) return PTR_ERR(shm); @@ -138,6 +136,43 @@ static int tee_ioctl_shm_alloc(struct tee_context *ctx, return ret; }
+static int +tee_ioctl_shm_register(struct tee_context *ctx, + struct tee_ioctl_shm_register_data __user *udata) +{ + long ret; + struct tee_ioctl_shm_register_data data; + struct tee_shm *shm; + + if (copy_from_user(&data, udata, sizeof(data))) + return -EFAULT; + + /* Currently no input flags are supported */ + if (data.flags) + return -EINVAL; + + shm = tee_shm_register(ctx, data.addr, data.length, + TEE_SHM_DMA_BUF | TEE_SHM_USER_MAPPED); + if (IS_ERR(shm)) + return PTR_ERR(shm); + + data.id = shm->id; + data.flags = shm->flags; + data.length = shm->size; + + if (copy_to_user(udata, &data, sizeof(data))) + ret = -EFAULT; + else + ret = tee_shm_get_fd(shm); + /* + * When user space closes the file descriptor the shared memory + * should be freed or if tee_shm_get_fd() failed then it will + * be freed immediately. + */ + tee_shm_put(shm); + return ret; +} + static int params_from_user(struct tee_context *ctx, struct tee_param *params, size_t num_params, struct tee_ioctl_param __user *uparams) @@ -586,6 +621,8 @@ static long tee_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) return tee_ioctl_version(ctx, uarg); case TEE_IOC_SHM_ALLOC: return tee_ioctl_shm_alloc(ctx, uarg); + case TEE_IOC_SHM_REGISTER: + return tee_ioctl_shm_register(ctx, uarg); case TEE_IOC_OPEN_SESSION: return tee_ioctl_open_session(ctx, uarg); case TEE_IOC_INVOKE: diff --git a/drivers/tee/tee_shm.c b/drivers/tee/tee_shm.c index fdda89e..177e341 100644 --- a/drivers/tee/tee_shm.c +++ b/drivers/tee/tee_shm.c @@ -23,7 +23,6 @@ static void tee_shm_release(struct tee_shm *shm) { struct tee_device *teedev = shm->teedev; - struct tee_shm_pool_mgr *poolm;
mutex_lock(&teedev->mutex); idr_remove(&teedev->idr, shm->id); @@ -31,12 +30,29 @@ static void tee_shm_release(struct tee_shm *shm) list_del(&shm->link); mutex_unlock(&teedev->mutex);
- if (shm->flags & TEE_SHM_DMA_BUF) - poolm = teedev->pool->dma_buf_mgr; - else - poolm = teedev->pool->private_mgr; + if (shm->flags & TEE_SHM_POOL) { + struct tee_shm_pool_mgr *poolm; + + if (shm->flags & TEE_SHM_DMA_BUF) + poolm = teedev->pool->dma_buf_mgr; + else + poolm = teedev->pool->private_mgr; + + poolm->ops->free(poolm, shm); + } else if (shm->flags & TEE_SHM_REGISTER) { + size_t n; + int rc = teedev->desc->ops->shm_unregister(shm->ctx, shm); + + if (rc) + dev_err(teedev->dev.parent, + "unregister shm %p failed: %d", shm, rc); + + for (n = 0; n < shm->num_pages; n++) + put_page(shm->pages[n]); + + kfree(shm->pages); + }
- poolm->ops->free(poolm, shm); kfree(shm);
tee_device_put(teedev); @@ -76,6 +92,10 @@ static int tee_shm_op_mmap(struct dma_buf *dmabuf, struct vm_area_struct *vma) struct tee_shm *shm = dmabuf->priv; size_t size = vma->vm_end - vma->vm_start;
+ /* Refuse sharing shared memory provided by application */ + if (shm->flags & TEE_SHM_REGISTER) + return -EINVAL; + return remap_pfn_range(vma, vma->vm_start, shm->paddr >> PAGE_SHIFT, size, vma->vm_page_prot); } @@ -89,26 +109,20 @@ static const struct dma_buf_ops tee_shm_dma_buf_ops = { .mmap = tee_shm_op_mmap, };
-/** - * tee_shm_alloc() - Allocate shared memory - * @ctx: Context that allocates the shared memory - * @size: Requested size of shared memory - * @flags: Flags setting properties for the requested shared memory. - * - * Memory allocated as global shared memory is automatically freed when the - * TEE file pointer is closed. The @flags field uses the bits defined by - * TEE_SHM_* in <linux/tee_drv.h>. TEE_SHM_MAPPED must currently always be - * set. If TEE_SHM_DMA_BUF global shared memory will be allocated and - * associated with a dma-buf handle, else driver private memory. - */ -struct tee_shm *tee_shm_alloc(struct tee_context *ctx, size_t size, u32 flags) +struct tee_shm *__tee_shm_alloc(struct tee_context *ctx, + struct tee_device *teedev, + size_t size, u32 flags) { - struct tee_device *teedev = ctx->teedev; struct tee_shm_pool_mgr *poolm = NULL; struct tee_shm *shm; void *ret; int rc;
+ if (ctx && ctx->teedev != teedev) { + dev_err(teedev->dev.parent, "ctx and teedev mismatch\n"); + return ERR_PTR(-EINVAL); + } + if (!(flags & TEE_SHM_MAPPED)) { dev_err(teedev->dev.parent, "only mapped allocations supported\n"); @@ -135,7 +149,7 @@ struct tee_shm *tee_shm_alloc(struct tee_context *ctx, size_t size, u32 flags) goto err_dev_put; }
- shm->flags = flags; + shm->flags = flags | TEE_SHM_POOL; shm->teedev = teedev; shm->ctx = ctx; if (flags & TEE_SHM_DMA_BUF) @@ -171,9 +185,12 @@ struct tee_shm *tee_shm_alloc(struct tee_context *ctx, size_t size, u32 flags) goto err_rem; } } - mutex_lock(&teedev->mutex); - list_add_tail(&shm->link, &ctx->list_shm); - mutex_unlock(&teedev->mutex); + + if (ctx) { + mutex_lock(&teedev->mutex); + list_add_tail(&shm->link, &ctx->list_shm); + mutex_unlock(&teedev->mutex); + }
return shm; err_rem: @@ -188,8 +205,139 @@ struct tee_shm *tee_shm_alloc(struct tee_context *ctx, size_t size, u32 flags) tee_device_put(teedev); return ret; } +/** + * tee_shm_alloc() - Allocate shared memory + * @ctx: Context that allocates the shared memory + * @size: Requested size of shared memory + * @flags: Flags setting properties for the requested shared memory. + * + * Memory allocated as global shared memory is automatically freed when the + * TEE file pointer is closed. The @flags field uses the bits defined by + * TEE_SHM_* in <linux/tee_drv.h>. TEE_SHM_MAPPED must currently always be + * set. If TEE_SHM_DMA_BUF global shared memory will be allocated and + * associated with a dma-buf handle, else driver private memory. + */ +struct tee_shm *tee_shm_alloc(struct tee_context *ctx, size_t size, u32 flags) +{ + return __tee_shm_alloc(ctx, ctx->teedev, size, flags); +} EXPORT_SYMBOL_GPL(tee_shm_alloc);
+struct tee_shm *tee_shm_priv_alloc(struct tee_device *teedev, size_t size) +{ + return __tee_shm_alloc(NULL, teedev, size, TEE_SHM_MAPPED); +} +EXPORT_SYMBOL_GPL(tee_shm_priv_alloc); + +struct tee_shm *tee_shm_register(struct tee_context *ctx, unsigned long addr, + size_t length, u32 flags) +{ + struct tee_device *teedev = ctx->teedev; + const u32 req_flags = TEE_SHM_DMA_BUF | TEE_SHM_USER_MAPPED; + struct tee_shm *shm; + void *ret; + int rc; + int num_pages; + unsigned long start; + + if (flags != req_flags) + return ERR_PTR(-ENOTSUPP); + + if (!tee_device_get(teedev)) + return ERR_PTR(-EINVAL); + + if (!teedev->desc->ops->shm_register || + !teedev->desc->ops->shm_unregister) { + tee_device_put(teedev); + return ERR_PTR(-ENOTSUPP); + } + + shm = kzalloc(sizeof(*shm), GFP_KERNEL); + if (!shm) { + ret = ERR_PTR(-ENOMEM); + goto err; + } + + shm->flags = flags | TEE_SHM_REGISTER; + shm->teedev = teedev; + shm->ctx = ctx; + shm->id = -1; + start = rounddown(addr, PAGE_SIZE); + shm->offset = addr - start; + shm->size = length; + num_pages = (roundup(addr + length, PAGE_SIZE) - start) / PAGE_SIZE; + shm->pages = kcalloc(num_pages, sizeof(*shm->pages), GFP_KERNEL); + if (!shm->pages) { + ret = ERR_PTR(-ENOMEM); + goto err; + } + + rc = get_user_pages_fast(start, num_pages, 1, shm->pages); + if (rc > 0) + shm->num_pages = rc; + if (rc != num_pages) { + if (rc > 0) + rc = -ENOMEM; + ret = ERR_PTR(rc); + goto err; + } + + mutex_lock(&teedev->mutex); + shm->id = idr_alloc(&teedev->idr, shm, 1, 0, GFP_KERNEL); + mutex_unlock(&teedev->mutex); + + if (shm->id < 0) { + ret = ERR_PTR(shm->id); + goto err; + } + + rc = teedev->desc->ops->shm_register(ctx, shm, shm->pages, + shm->num_pages); + if (rc) { + ret = ERR_PTR(rc); + goto err; + } + + if (flags & TEE_SHM_DMA_BUF) { + DEFINE_DMA_BUF_EXPORT_INFO(exp_info); + + exp_info.ops = &tee_shm_dma_buf_ops; + exp_info.size = shm->size; + exp_info.flags = O_RDWR; + exp_info.priv = shm; + + shm->dmabuf = dma_buf_export(&exp_info); + if (IS_ERR(shm->dmabuf)) { + ret = ERR_CAST(shm->dmabuf); + teedev->desc->ops->shm_unregister(ctx, shm); + goto err; + } + } + + mutex_lock(&teedev->mutex); + list_add_tail(&shm->link, &ctx->list_shm); + mutex_unlock(&teedev->mutex); + + return shm; +err: + if (shm) { + size_t n; + + if (shm->id >= 0) { + mutex_lock(&teedev->mutex); + idr_remove(&teedev->idr, shm->id); + mutex_unlock(&teedev->mutex); + } + for (n = 0; n < shm->num_pages; n++) + put_page(shm->pages[n]); + kfree(shm->pages); + } + kfree(shm); + tee_device_put(teedev); + return ret; +} +EXPORT_SYMBOL_GPL(tee_shm_register); + /** * tee_shm_get_fd() - Increase reference count and return file descriptor * @shm: Shared memory handle @@ -197,10 +345,9 @@ EXPORT_SYMBOL_GPL(tee_shm_alloc); */ int tee_shm_get_fd(struct tee_shm *shm) { - u32 req_flags = TEE_SHM_MAPPED | TEE_SHM_DMA_BUF; int fd;
- if ((shm->flags & req_flags) != req_flags) + if (!(shm->flags & TEE_SHM_DMA_BUF)) return -EINVAL;
fd = dma_buf_fd(shm->dmabuf, O_CLOEXEC); @@ -238,6 +385,8 @@ EXPORT_SYMBOL_GPL(tee_shm_free); */ int tee_shm_va2pa(struct tee_shm *shm, void *va, phys_addr_t *pa) { + if (!(shm->flags & TEE_SHM_MAPPED)) + return -EINVAL; /* Check that we're in the range of the shm */ if ((char *)va < (char *)shm->kaddr) return -EINVAL; @@ -258,6 +407,8 @@ EXPORT_SYMBOL_GPL(tee_shm_va2pa); */ int tee_shm_pa2va(struct tee_shm *shm, phys_addr_t pa, void **va) { + if (!(shm->flags & TEE_SHM_MAPPED)) + return -EINVAL; /* Check that we're in the range of the shm */ if (pa < shm->paddr) return -EINVAL; @@ -284,6 +435,8 @@ EXPORT_SYMBOL_GPL(tee_shm_pa2va); */ void *tee_shm_get_va(struct tee_shm *shm, size_t offs) { + if (!(shm->flags & TEE_SHM_MAPPED)) + return ERR_PTR(-EINVAL); if (offs >= shm->size) return ERR_PTR(-EINVAL); return (char *)shm->kaddr + offs; diff --git a/include/linux/tee_drv.h b/include/linux/tee_drv.h index e9be4a4..70b9c73 100644 --- a/include/linux/tee_drv.h +++ b/include/linux/tee_drv.h @@ -25,8 +25,12 @@ * specific TEE driver. */
-#define TEE_SHM_MAPPED 0x1 /* Memory mapped by the kernel */ -#define TEE_SHM_DMA_BUF 0x2 /* Memory with dma-buf handle */ +#define TEE_SHM_MAPPED BIT(0) /* Memory mapped by the kernel */ +#define TEE_SHM_DMA_BUF BIT(1) /* Memory with dma-buf handle */ +#define TEE_SHM_EXT_DMA_BUF BIT(2) /* Memory with dma-buf handle */ +#define TEE_SHM_REGISTER BIT(3) /* Memory registered in secure world */ +#define TEE_SHM_USER_MAPPED BIT(4) /* Memory mapped in user space */ +#define TEE_SHM_POOL BIT(5) /* Memory allocated from pool */
struct device; struct tee_device; @@ -76,6 +80,8 @@ struct tee_param { * @cancel_req: request cancel of an ongoing invoke or open * @supp_revc: called for supplicant to get a command * @supp_send: called for supplicant to send a response + * @shm_register: register shared memory buffer in TEE + * @shm_unregister: unregister shared memory buffer in TEE */ struct tee_driver_ops { void (*get_version)(struct tee_device *teedev, @@ -94,6 +100,9 @@ struct tee_driver_ops { struct tee_param *param); int (*supp_send)(struct tee_context *ctx, u32 ret, u32 num_params, struct tee_param *param); + int (*shm_register)(struct tee_context *ctx, struct tee_shm *shm, + struct page **pages, size_t num_pages); + int (*shm_unregister)(struct tee_context *ctx, struct tee_shm *shm); };
/** @@ -302,6 +311,30 @@ void *tee_get_drvdata(struct tee_device *teedev); struct tee_shm *tee_shm_alloc(struct tee_context *ctx, size_t size, u32 flags);
/** + * tee_shm_priv_alloc() - Allocate shared memory privately + * @dev: Device that allocates the shared memory + * @size: Requested size of shared memory + * + * Allocates shared memory buffer that is not associated with any client + * context. Such buffers are owned by TEE driver and used for internal calls. + * + * @returns a pointer to 'struct tee_shm' + */ +struct tee_shm *tee_shm_priv_alloc(struct tee_device *teedev, size_t size); + +/** + * tee_shm_register() - Register shared memory buffer + * @ctx: Context that registers the shared memory + * @addr: Address is userspace of the shared buffer + * @length: Length of the shared buffer + * @flags: Flags setting properties for the requested shared memory. + * + * @returns a pointer to 'struct tee_shm' + */ +struct tee_shm *tee_shm_register(struct tee_context *ctx, unsigned long addr, + size_t length, u32 flags); + +/** * tee_shm_free() - Free shared memory * @shm: Handle to shared memory to free */ @@ -366,4 +399,14 @@ int tee_shm_get_id(struct tee_shm *shm); */ struct tee_shm *tee_shm_get_from_id(struct tee_context *ctx, int id);
+/** + * tee_shm_is_registered() - Check if shared memory object in registered in TEE + * @shm: Shared memory handle + * @returns true if object is registered in TEE + */ +static inline bool tee_shm_is_registered(struct tee_shm *shm) +{ + return shm && (shm->flags & TEE_SHM_REGISTER); +} + #endif /*__TEE_DRV_H*/ diff --git a/include/uapi/linux/tee.h b/include/uapi/linux/tee.h index 688782e..d41a07a 100644 --- a/include/uapi/linux/tee.h +++ b/include/uapi/linux/tee.h @@ -50,6 +50,7 @@
#define TEE_GEN_CAP_GP (1 << 0)/* GlobalPlatform compliant TEE */ #define TEE_GEN_CAP_PRIVILEGED (1 << 1)/* Privileged device (for supplicant) */ +#define TEE_GEN_CAP_REG_MEM (1 << 2)/* Supports registering shared memory */
/* * TEE Implementation ID @@ -332,6 +333,35 @@ struct tee_iocl_supp_send_arg { #define TEE_IOC_SUPPL_SEND _IOR(TEE_IOC_MAGIC, TEE_IOC_BASE + 7, \ struct tee_ioctl_buf_data)
+/** + * struct tee_ioctl_shm_register_data - Shared memory register argument + * @addr: [in] Start address of shared memory to register + * @length: [in/out] Length of shared memory to register + * @flags: [in/out] Flags to/from registration. + * @id: [out] Identifier of the shared memory + * + * The flags field should currently be zero as input. Updated by the call + * with actual flags as defined by TEE_IOCTL_SHM_* above. + * This structure is used as argument for TEE_IOC_SHM_REGISTER below. + */ +struct tee_ioctl_shm_register_data { + __u64 addr; + __u64 length; + __u32 flags; + __s32 id; +}; + +/** + * TEE_IOC_SHM_REGISTER - Register shared memory argument + * + * Registers shared memory between the user space process and secure OS. + * + * Returns a file descriptor on success or < 0 on failure + * + * The shared memory is unregisterred when the descriptor is closed. + */ +#define TEE_IOC_SHM_REGISTER _IOWR(TEE_IOC_MAGIC, TEE_IOC_BASE + 9, \ + struct tee_ioctl_shm_register_data) /* * Five syscalls are used when communicating with the TEE driver. * open(): opens the device associated with the driver