Hi Jens,
On Wed, Mar 05, 2025 at 02:04:12PM +0100, Jens Wiklander wrote:
From: Etienne Carriere etienne.carriere@linaro.org
Enable userspace to create a tee_shm object that refers to a dmabuf reference.
Userspace registers the dmabuf file descriptor as in a tee_shm object. The registration is completed with a tee_shm file descriptor returned to userspace.
Userspace is free to close the dmabuf file descriptor now since all the resources are now held via the tee_shm object.
Closing the tee_shm file descriptor will release all resources used by the tee_shm object.
This change only support dmabuf references that relates to physically contiguous memory buffers.
New tee_shm flag to identify tee_shm objects built from a registered dmabuf, TEE_SHM_DMA_BUF.
Signed-off-by: Etienne Carriere etienne.carriere@linaro.org Signed-off-by: Olivier Masse olivier.masse@nxp.com Signed-off-by: Jens Wiklander jens.wiklander@linaro.org
drivers/tee/tee_core.c | 145 ++++++++++++++++++++++++++----------- drivers/tee/tee_private.h | 1 + drivers/tee/tee_shm.c | 146 ++++++++++++++++++++++++++++++++++++-- include/linux/tee_core.h | 1 + include/linux/tee_drv.h | 10 +++ include/uapi/linux/tee.h | 29 ++++++++ 6 files changed, 288 insertions(+), 44 deletions(-)
I am still trying to find if we really need a separate IOCTL to register DMA heap with TEE subsystem. Can't we initialize tee_shm as a member of struct tee_heap_buffer in tee_dma_heap_alloc() where the allocation happens? We can always find a reference back to tee_shm object from DMA buffer.
-Sumit
diff --git a/drivers/tee/tee_core.c b/drivers/tee/tee_core.c index 685afcaa3ea1..3a71643766d5 100644 --- a/drivers/tee/tee_core.c +++ b/drivers/tee/tee_core.c @@ -353,6 +353,103 @@ tee_ioctl_shm_register(struct tee_context *ctx, return ret; } +static int +tee_ioctl_shm_register_fd(struct tee_context *ctx,
struct tee_ioctl_shm_register_fd_data __user *udata)+{
- struct tee_ioctl_shm_register_fd_data data;
- struct tee_shm *shm;
- long ret;
- 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_fd(ctx, data.fd);
- if (IS_ERR(shm))
return -EINVAL;- data.id = shm->id;
- data.flags = shm->flags;
- data.size = 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 param_from_user_memref(struct tee_context *ctx,
struct tee_param_memref *memref,struct tee_ioctl_param *ip)+{
- struct tee_shm *shm;
- size_t offs = 0;
- /*
* If a NULL pointer is passed to a TA in the TEE,* the ip.c IOCTL parameters is set to TEE_MEMREF_NULL* indicating a NULL memory reference.*/- if (ip->c != TEE_MEMREF_NULL) {
/** If we fail to get a pointer to a shared* memory object (and increase the ref count)* from an identifier we return an error. All* pointers that has been added in params have* an increased ref count. It's the callers* responibility to do tee_shm_put() on all* resolved pointers.*/shm = tee_shm_get_from_id(ctx, ip->c);if (IS_ERR(shm))return PTR_ERR(shm);/** Ensure offset + size does not overflow* offset and does not overflow the size of* the referred shared memory object.*/if ((ip->a + ip->b) < ip->a ||(ip->a + ip->b) > shm->size) {tee_shm_put(shm);return -EINVAL;}if (shm->flags & TEE_SHM_DMA_BUF) {struct tee_shm *parent_shm;parent_shm = tee_shm_get_parent_shm(shm, &offs);if (parent_shm) {tee_shm_put(shm);shm = parent_shm;}}- } else if (ctx->cap_memref_null) {
/* Pass NULL pointer to OP-TEE */shm = NULL;- } else {
return -EINVAL;- }
- memref->shm_offs = ip->a + offs;
- memref->size = ip->b;
- memref->shm = shm;
- return 0;
+}
static int params_from_user(struct tee_context *ctx, struct tee_param *params, size_t num_params, struct tee_ioctl_param __user *uparams) @@ -360,8 +457,8 @@ static int params_from_user(struct tee_context *ctx, struct tee_param *params, size_t n; for (n = 0; n < num_params; n++) {
struct tee_shm *shm;
int rc;if (copy_from_user(&ip, uparams + n, sizeof(ip))) return -EFAULT; @@ -384,45 +481,10 @@ static int params_from_user(struct tee_context *ctx, struct tee_param *params, case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INPUT: case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_OUTPUT: case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INOUT:
/** If a NULL pointer is passed to a TA in the TEE,* the ip.c IOCTL parameters is set to TEE_MEMREF_NULL* indicating a NULL memory reference.*/if (ip.c != TEE_MEMREF_NULL) {/** If we fail to get a pointer to a shared* memory object (and increase the ref count)* from an identifier we return an error. All* pointers that has been added in params have* an increased ref count. It's the callers* responibility to do tee_shm_put() on all* resolved pointers.*/shm = tee_shm_get_from_id(ctx, ip.c);if (IS_ERR(shm))return PTR_ERR(shm);/** Ensure offset + size does not overflow* offset and does not overflow the size of* the referred shared memory object.*/if ((ip.a + ip.b) < ip.a ||(ip.a + ip.b) > shm->size) {tee_shm_put(shm);return -EINVAL;}} else if (ctx->cap_memref_null) {/* Pass NULL pointer to OP-TEE */shm = NULL;} else {return -EINVAL;}params[n].u.memref.shm_offs = ip.a;params[n].u.memref.size = ip.b;params[n].u.memref.shm = shm;
rc = param_from_user_memref(ctx, ¶ms[n].u.memref,&ip);if (rc)return rc; break;@@ -827,6 +889,8 @@ static long tee_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) return tee_ioctl_shm_alloc(ctx, uarg); case TEE_IOC_SHM_REGISTER: return tee_ioctl_shm_register(ctx, uarg);
- case TEE_IOC_SHM_REGISTER_FD:
return tee_ioctl_shm_register_fd(ctx, uarg);@@ -1288,3 +1352,4 @@ MODULE_AUTHOR("Linaro"); MODULE_DESCRIPTION("TEE Driver"); MODULE_VERSION("1.0"); MODULE_LICENSE("GPL v2"); +MODULE_IMPORT_NS("DMA_BUF"); diff --git a/drivers/tee/tee_private.h b/drivers/tee/tee_private.h index 6c6ff5d5eed2..aad7f6c7e0f0 100644 --- a/drivers/tee/tee_private.h +++ b/drivers/tee/tee_private.h @@ -24,6 +24,7 @@ void teedev_ctx_put(struct tee_context *ctx); struct tee_shm *tee_shm_alloc_user_buf(struct tee_context *ctx, size_t size); struct tee_shm *tee_shm_register_user_buf(struct tee_context *ctx, unsigned long addr, size_t length); +struct tee_shm *tee_shm_get_parent_shm(struct tee_shm *shm, size_t *offs); int tee_heap_update_from_dma_buf(struct tee_device *teedev, struct dma_buf *dmabuf, size_t *offset, diff --git a/drivers/tee/tee_shm.c b/drivers/tee/tee_shm.c index daf6e5cfd59a..8b79918468b5 100644 --- a/drivers/tee/tee_shm.c +++ b/drivers/tee/tee_shm.c @@ -4,6 +4,7 @@ */ #include <linux/anon_inodes.h> #include <linux/device.h> +#include <linux/dma-buf.h> #include <linux/idr.h> #include <linux/io.h> #include <linux/mm.h> @@ -15,6 +16,16 @@ #include <linux/highmem.h> #include "tee_private.h" +/* extra references appended to shm object for registered shared memory */ +struct tee_shm_dmabuf_ref {
- struct tee_shm shm;
- size_t offset;
- struct dma_buf *dmabuf;
- struct dma_buf_attachment *attach;
- struct sg_table *sgt;
- struct tee_shm *parent_shm;
+};
static void shm_put_kernel_pages(struct page **pages, size_t page_count) { size_t n; @@ -45,7 +56,23 @@ static void release_registered_pages(struct tee_shm *shm) static void tee_shm_release(struct tee_device *teedev, struct tee_shm *shm) {
- if (shm->flags & TEE_SHM_POOL) {
- struct tee_shm *parent_shm = NULL;
- void *p = shm;
- if (shm->flags & TEE_SHM_DMA_BUF) {
struct tee_shm_dmabuf_ref *ref;ref = container_of(shm, struct tee_shm_dmabuf_ref, shm);parent_shm = ref->parent_shm;p = ref;if (ref->attach) {dma_buf_unmap_attachment(ref->attach, ref->sgt,DMA_BIDIRECTIONAL);dma_buf_detach(ref->dmabuf, ref->attach);}dma_buf_put(ref->dmabuf);- } else if (shm->flags & TEE_SHM_POOL) { teedev->pool->ops->free(teedev->pool, shm); } else if (shm->flags & TEE_SHM_DYNAMIC) { int rc = teedev->desc->ops->shm_unregister(shm->ctx, shm);
@@ -57,9 +84,10 @@ static void tee_shm_release(struct tee_device *teedev, struct tee_shm *shm) release_registered_pages(shm); }
- teedev_ctx_put(shm->ctx);
- if (shm->ctx)
teedev_ctx_put(shm->ctx);
- kfree(shm);
- kfree(p);
tee_device_put(teedev); } @@ -169,7 +197,7 @@ struct tee_shm *tee_shm_alloc_user_buf(struct tee_context *ctx, size_t size)
- tee_client_invoke_func(). The memory allocated is later freed with a
- call to tee_shm_free().
- @returns a pointer to 'struct tee_shm'
*/
- @returns a pointer to 'struct tee_shm' on success, and ERR_PTR on failure
struct tee_shm *tee_shm_alloc_kernel_buf(struct tee_context *ctx, size_t size) { @@ -179,6 +207,116 @@ struct tee_shm *tee_shm_alloc_kernel_buf(struct tee_context *ctx, size_t size) } EXPORT_SYMBOL_GPL(tee_shm_alloc_kernel_buf); +struct tee_shm *tee_shm_register_fd(struct tee_context *ctx, int fd) +{
- struct tee_shm_dmabuf_ref *ref;
- int rc;
- if (!tee_device_get(ctx->teedev))
return ERR_PTR(-EINVAL);- teedev_ctx_get(ctx);
- ref = kzalloc(sizeof(*ref), GFP_KERNEL);
- if (!ref) {
rc = -ENOMEM;goto err_put_tee;- }
- refcount_set(&ref->shm.refcount, 1);
- ref->shm.ctx = ctx;
- ref->shm.id = -1;
- ref->shm.flags = TEE_SHM_DMA_BUF;
- ref->dmabuf = dma_buf_get(fd);
- if (IS_ERR(ref->dmabuf)) {
rc = PTR_ERR(ref->dmabuf);goto err_kfree_ref;- }
- rc = tee_heap_update_from_dma_buf(ctx->teedev, ref->dmabuf,
&ref->offset, &ref->shm,&ref->parent_shm);- if (!rc)
goto out;- if (rc != -EINVAL)
goto err_put_dmabuf;- ref->attach = dma_buf_attach(ref->dmabuf, &ctx->teedev->dev);
- if (IS_ERR(ref->attach)) {
rc = PTR_ERR(ref->attach);goto err_put_dmabuf;- }
- ref->sgt = dma_buf_map_attachment(ref->attach, DMA_BIDIRECTIONAL);
- if (IS_ERR(ref->sgt)) {
rc = PTR_ERR(ref->sgt);goto err_detach;- }
- if (sg_nents(ref->sgt->sgl) != 1) {
rc = PTR_ERR(ref->sgt->sgl);goto err_unmap_attachement;- }
- ref->shm.paddr = page_to_phys(sg_page(ref->sgt->sgl));
- ref->shm.size = ref->sgt->sgl->length;
+out:
- mutex_lock(&ref->shm.ctx->teedev->mutex);
- ref->shm.id = idr_alloc(&ref->shm.ctx->teedev->idr, &ref->shm,
1, 0, GFP_KERNEL);- mutex_unlock(&ref->shm.ctx->teedev->mutex);
- if (ref->shm.id < 0) {
rc = ref->shm.id;if (ref->attach)goto err_unmap_attachement;goto err_put_dmabuf;- }
- return &ref->shm;
+err_unmap_attachement:
- dma_buf_unmap_attachment(ref->attach, ref->sgt, DMA_BIDIRECTIONAL);
+err_detach:
- dma_buf_detach(ref->dmabuf, ref->attach);
+err_put_dmabuf:
- dma_buf_put(ref->dmabuf);
+err_kfree_ref:
- kfree(ref);
+err_put_tee:
- teedev_ctx_put(ctx);
- tee_device_put(ctx->teedev);
- return ERR_PTR(rc);
+} +EXPORT_SYMBOL_GPL(tee_shm_register_fd);
+struct tee_shm *tee_shm_get_parent_shm(struct tee_shm *shm, size_t *offs) +{
- struct tee_shm *parent_shm = NULL;
- if (shm->flags & TEE_SHM_DMA_BUF) {
struct tee_shm_dmabuf_ref *ref;ref = container_of(shm, struct tee_shm_dmabuf_ref, shm);if (ref->parent_shm) {/** the shm already has one reference to* ref->parent_shm so we should be clear of 0.* We're getting another reference since the caller* of this function expects to put the returned* parent_shm when it's done with it.*/parent_shm = ref->parent_shm;refcount_inc(&parent_shm->refcount);*offs = ref->offset;}- }
- return parent_shm;
+}
/**
- tee_shm_alloc_priv_buf() - Allocate shared memory for a privately shared
kernel bufferdiff --git a/include/linux/tee_core.h b/include/linux/tee_core.h index 16ef078247ae..6bd833b6d0e1 100644 --- a/include/linux/tee_core.h +++ b/include/linux/tee_core.h @@ -28,6 +28,7 @@ #define TEE_SHM_USER_MAPPED BIT(1) /* Memory mapped in user space */ #define TEE_SHM_POOL BIT(2) /* Memory allocated from pool */ #define TEE_SHM_PRIV BIT(3) /* Memory private to TEE driver */ +#define TEE_SHM_DMA_BUF BIT(4) /* Memory with dma-buf handle */ #define TEE_DEVICE_FLAG_REGISTERED 0x1 #define TEE_MAX_DEV_NAME_LEN 32 diff --git a/include/linux/tee_drv.h b/include/linux/tee_drv.h index a54c203000ed..824f1251de60 100644 --- a/include/linux/tee_drv.h +++ b/include/linux/tee_drv.h @@ -116,6 +116,16 @@ struct tee_shm *tee_shm_alloc_kernel_buf(struct tee_context *ctx, size_t size); struct tee_shm *tee_shm_register_kernel_buf(struct tee_context *ctx, void *addr, size_t length); +/**
- tee_shm_register_fd() - Register shared memory from file descriptor
- @ctx: Context that allocates the shared memory
- @fd: Shared memory file descriptor reference
- @returns a pointer to 'struct tee_shm' on success, and ERR_PTR on failure
- */
+struct tee_shm *tee_shm_register_fd(struct tee_context *ctx, int fd);
/**
- tee_shm_free() - Free shared memory
- @shm: Handle to shared memory to free
diff --git a/include/uapi/linux/tee.h b/include/uapi/linux/tee.h index d0430bee8292..1f9a4ac2b211 100644 --- a/include/uapi/linux/tee.h +++ b/include/uapi/linux/tee.h @@ -118,6 +118,35 @@ struct tee_ioctl_shm_alloc_data { #define TEE_IOC_SHM_ALLOC _IOWR(TEE_IOC_MAGIC, TEE_IOC_BASE + 1, \ struct tee_ioctl_shm_alloc_data) +/**
- struct tee_ioctl_shm_register_fd_data - Shared memory registering argument
- @fd: [in] File descriptor identifying the shared memory
- @size: [out] Size of shared memory to allocate
- @flags: [in] Flags to/from allocation.
- @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_FD below.
- */
+struct tee_ioctl_shm_register_fd_data {
- __s64 fd;
- __u64 size;
- __u32 flags;
- __s32 id;
+};
+/**
- TEE_IOC_SHM_REGISTER_FD - register a shared memory from a file descriptor
- Returns a file descriptor on success or < 0 on failure
- The returned file descriptor refers to the shared memory object in kernel
- land. The shared memory is freed when the descriptor is closed.
- */
+#define TEE_IOC_SHM_REGISTER_FD _IOWR(TEE_IOC_MAGIC, TEE_IOC_BASE + 8, \
struct tee_ioctl_shm_register_fd_data)/**
- struct tee_ioctl_buf_data - Variable sized buffer
- @buf_ptr: [in] A __user pointer to a buffer
-- 2.43.0