diff options
Diffstat (limited to 'drivers/tee/tee_heap.c')
| -rw-r--r-- | drivers/tee/tee_heap.c | 500 |
1 files changed, 500 insertions, 0 deletions
diff --git a/drivers/tee/tee_heap.c b/drivers/tee/tee_heap.c new file mode 100644 index 000000000000..d8d7735cdffb --- /dev/null +++ b/drivers/tee/tee_heap.c @@ -0,0 +1,500 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (c) 2025, Linaro Limited + */ + +#include <linux/dma-buf.h> +#include <linux/dma-heap.h> +#include <linux/genalloc.h> +#include <linux/module.h> +#include <linux/scatterlist.h> +#include <linux/slab.h> +#include <linux/tee_core.h> +#include <linux/xarray.h> + +#include "tee_private.h" + +struct tee_dma_heap { + struct dma_heap *heap; + enum tee_dma_heap_id id; + struct kref kref; + struct tee_protmem_pool *pool; + struct tee_device *teedev; + bool shutting_down; + /* Protects pool, teedev, and shutting_down above */ + struct mutex mu; +}; + +struct tee_heap_buffer { + struct tee_dma_heap *heap; + size_t size; + size_t offs; + struct sg_table table; +}; + +struct tee_heap_attachment { + struct sg_table table; + struct device *dev; +}; + +struct tee_protmem_static_pool { + struct tee_protmem_pool pool; + struct gen_pool *gen_pool; + phys_addr_t pa_base; +}; + +#if IS_ENABLED(CONFIG_TEE_DMABUF_HEAPS) +static DEFINE_XARRAY_ALLOC(tee_dma_heap); + +static void tee_heap_release(struct kref *kref) +{ + struct tee_dma_heap *h = container_of(kref, struct tee_dma_heap, kref); + + h->pool->ops->destroy_pool(h->pool); + tee_device_put(h->teedev); + h->pool = NULL; + h->teedev = NULL; +} + +static void put_tee_heap(struct tee_dma_heap *h) +{ + kref_put(&h->kref, tee_heap_release); +} + +static void get_tee_heap(struct tee_dma_heap *h) +{ + kref_get(&h->kref); +} + +static int copy_sg_table(struct sg_table *dst, struct sg_table *src) +{ + struct scatterlist *dst_sg; + struct scatterlist *src_sg; + int ret; + int i; + + ret = sg_alloc_table(dst, src->orig_nents, GFP_KERNEL); + if (ret) + return ret; + + dst_sg = dst->sgl; + for_each_sgtable_sg(src, src_sg, i) { + sg_set_page(dst_sg, sg_page(src_sg), src_sg->length, + src_sg->offset); + dst_sg = sg_next(dst_sg); + } + + return 0; +} + +static int tee_heap_attach(struct dma_buf *dmabuf, + struct dma_buf_attachment *attachment) +{ + struct tee_heap_buffer *buf = dmabuf->priv; + struct tee_heap_attachment *a; + int ret; + + a = kzalloc(sizeof(*a), GFP_KERNEL); + if (!a) + return -ENOMEM; + + ret = copy_sg_table(&a->table, &buf->table); + if (ret) { + kfree(a); + return ret; + } + + a->dev = attachment->dev; + attachment->priv = a; + + return 0; +} + +static void tee_heap_detach(struct dma_buf *dmabuf, + struct dma_buf_attachment *attachment) +{ + struct tee_heap_attachment *a = attachment->priv; + + sg_free_table(&a->table); + kfree(a); +} + +static struct sg_table * +tee_heap_map_dma_buf(struct dma_buf_attachment *attachment, + enum dma_data_direction direction) +{ + struct tee_heap_attachment *a = attachment->priv; + int ret; + + ret = dma_map_sgtable(attachment->dev, &a->table, direction, + DMA_ATTR_SKIP_CPU_SYNC); + if (ret) + return ERR_PTR(ret); + + return &a->table; +} + +static void tee_heap_unmap_dma_buf(struct dma_buf_attachment *attachment, + struct sg_table *table, + enum dma_data_direction direction) +{ + struct tee_heap_attachment *a = attachment->priv; + + WARN_ON(&a->table != table); + + dma_unmap_sgtable(attachment->dev, table, direction, + DMA_ATTR_SKIP_CPU_SYNC); +} + +static void tee_heap_buf_free(struct dma_buf *dmabuf) +{ + struct tee_heap_buffer *buf = dmabuf->priv; + + buf->heap->pool->ops->free(buf->heap->pool, &buf->table); + mutex_lock(&buf->heap->mu); + put_tee_heap(buf->heap); + mutex_unlock(&buf->heap->mu); + kfree(buf); +} + +static const struct dma_buf_ops tee_heap_buf_ops = { + .attach = tee_heap_attach, + .detach = tee_heap_detach, + .map_dma_buf = tee_heap_map_dma_buf, + .unmap_dma_buf = tee_heap_unmap_dma_buf, + .release = tee_heap_buf_free, +}; + +static struct dma_buf *tee_dma_heap_alloc(struct dma_heap *heap, + unsigned long len, u32 fd_flags, + u64 heap_flags) +{ + struct tee_dma_heap *h = dma_heap_get_drvdata(heap); + DEFINE_DMA_BUF_EXPORT_INFO(exp_info); + struct tee_device *teedev = NULL; + struct tee_heap_buffer *buf; + struct tee_protmem_pool *pool; + struct dma_buf *dmabuf; + int rc; + + mutex_lock(&h->mu); + if (h->teedev) { + teedev = h->teedev; + pool = h->pool; + get_tee_heap(h); + } + mutex_unlock(&h->mu); + + if (!teedev) + return ERR_PTR(-EINVAL); + + buf = kzalloc(sizeof(*buf), GFP_KERNEL); + if (!buf) { + dmabuf = ERR_PTR(-ENOMEM); + goto err; + } + buf->size = len; + buf->heap = h; + + rc = pool->ops->alloc(pool, &buf->table, len, &buf->offs); + if (rc) { + dmabuf = ERR_PTR(rc); + goto err_kfree; + } + + exp_info.ops = &tee_heap_buf_ops; + exp_info.size = len; + exp_info.priv = buf; + exp_info.flags = fd_flags; + dmabuf = dma_buf_export(&exp_info); + if (IS_ERR(dmabuf)) + goto err_protmem_free; + + return dmabuf; + +err_protmem_free: + pool->ops->free(pool, &buf->table); +err_kfree: + kfree(buf); +err: + mutex_lock(&h->mu); + put_tee_heap(h); + mutex_unlock(&h->mu); + return dmabuf; +} + +static const struct dma_heap_ops tee_dma_heap_ops = { + .allocate = tee_dma_heap_alloc, +}; + +static const char *heap_id_2_name(enum tee_dma_heap_id id) +{ + switch (id) { + case TEE_DMA_HEAP_SECURE_VIDEO_PLAY: + return "protected,secure-video"; + case TEE_DMA_HEAP_TRUSTED_UI: + return "protected,trusted-ui"; + case TEE_DMA_HEAP_SECURE_VIDEO_RECORD: + return "protected,secure-video-record"; + default: + return NULL; + } +} + +static int alloc_dma_heap(struct tee_device *teedev, enum tee_dma_heap_id id, + struct tee_protmem_pool *pool) +{ + struct dma_heap_export_info exp_info = { + .ops = &tee_dma_heap_ops, + .name = heap_id_2_name(id), + }; + struct tee_dma_heap *h; + int rc; + + if (!exp_info.name) + return -EINVAL; + + if (xa_reserve(&tee_dma_heap, id, GFP_KERNEL)) { + if (!xa_load(&tee_dma_heap, id)) + return -EEXIST; + return -ENOMEM; + } + + h = kzalloc(sizeof(*h), GFP_KERNEL); + if (!h) + return -ENOMEM; + h->id = id; + kref_init(&h->kref); + h->teedev = teedev; + h->pool = pool; + mutex_init(&h->mu); + + exp_info.priv = h; + h->heap = dma_heap_add(&exp_info); + if (IS_ERR(h->heap)) { + rc = PTR_ERR(h->heap); + kfree(h); + + return rc; + } + + /* "can't fail" due to the call to xa_reserve() above */ + return WARN_ON(xa_is_err(xa_store(&tee_dma_heap, id, h, GFP_KERNEL))); +} + +int tee_device_register_dma_heap(struct tee_device *teedev, + enum tee_dma_heap_id id, + struct tee_protmem_pool *pool) +{ + struct tee_dma_heap *h; + int rc; + + if (!tee_device_get(teedev)) + return -EINVAL; + + h = xa_load(&tee_dma_heap, id); + if (h) { + mutex_lock(&h->mu); + if (h->teedev) { + rc = -EBUSY; + } else { + kref_init(&h->kref); + h->shutting_down = false; + h->teedev = teedev; + h->pool = pool; + rc = 0; + } + mutex_unlock(&h->mu); + } else { + rc = alloc_dma_heap(teedev, id, pool); + } + + if (rc) { + tee_device_put(teedev); + dev_err(&teedev->dev, "can't register DMA heap id %d (%s)\n", + id, heap_id_2_name(id)); + } + + return rc; +} +EXPORT_SYMBOL_GPL(tee_device_register_dma_heap); + +void tee_device_put_all_dma_heaps(struct tee_device *teedev) +{ + struct tee_dma_heap *h; + u_long i; + + xa_for_each(&tee_dma_heap, i, h) { + if (h) { + mutex_lock(&h->mu); + if (h->teedev == teedev && !h->shutting_down) { + h->shutting_down = true; + put_tee_heap(h); + } + mutex_unlock(&h->mu); + } + } +} +EXPORT_SYMBOL_GPL(tee_device_put_all_dma_heaps); + +int tee_heap_update_from_dma_buf(struct tee_device *teedev, + struct dma_buf *dmabuf, size_t *offset, + struct tee_shm *shm, + struct tee_shm **parent_shm) +{ + struct tee_heap_buffer *buf; + int rc; + + /* The DMA-buf must be from our heap */ + if (dmabuf->ops != &tee_heap_buf_ops) + return -EINVAL; + + buf = dmabuf->priv; + /* The buffer must be from the same teedev */ + if (buf->heap->teedev != teedev) + return -EINVAL; + + shm->size = buf->size; + + rc = buf->heap->pool->ops->update_shm(buf->heap->pool, &buf->table, + buf->offs, shm, parent_shm); + if (!rc && *parent_shm) + *offset = buf->offs; + + return rc; +} +#else +int tee_device_register_dma_heap(struct tee_device *teedev __always_unused, + enum tee_dma_heap_id id __always_unused, + struct tee_protmem_pool *pool __always_unused) +{ + return -EINVAL; +} +EXPORT_SYMBOL_GPL(tee_device_register_dma_heap); + +void +tee_device_put_all_dma_heaps(struct tee_device *teedev __always_unused) +{ +} +EXPORT_SYMBOL_GPL(tee_device_put_all_dma_heaps); + +int tee_heap_update_from_dma_buf(struct tee_device *teedev __always_unused, + struct dma_buf *dmabuf __always_unused, + size_t *offset __always_unused, + struct tee_shm *shm __always_unused, + struct tee_shm **parent_shm __always_unused) +{ + return -EINVAL; +} +#endif + +static struct tee_protmem_static_pool * +to_protmem_static_pool(struct tee_protmem_pool *pool) +{ + return container_of(pool, struct tee_protmem_static_pool, pool); +} + +static int protmem_pool_op_static_alloc(struct tee_protmem_pool *pool, + struct sg_table *sgt, size_t size, + size_t *offs) +{ + struct tee_protmem_static_pool *stp = to_protmem_static_pool(pool); + phys_addr_t pa; + int ret; + + pa = gen_pool_alloc(stp->gen_pool, size); + if (!pa) + return -ENOMEM; + + ret = sg_alloc_table(sgt, 1, GFP_KERNEL); + if (ret) { + gen_pool_free(stp->gen_pool, pa, size); + return ret; + } + + sg_set_page(sgt->sgl, phys_to_page(pa), size, 0); + *offs = pa - stp->pa_base; + + return 0; +} + +static void protmem_pool_op_static_free(struct tee_protmem_pool *pool, + struct sg_table *sgt) +{ + struct tee_protmem_static_pool *stp = to_protmem_static_pool(pool); + struct scatterlist *sg; + int i; + + for_each_sgtable_sg(sgt, sg, i) + gen_pool_free(stp->gen_pool, sg_phys(sg), sg->length); + sg_free_table(sgt); +} + +static int protmem_pool_op_static_update_shm(struct tee_protmem_pool *pool, + struct sg_table *sgt, size_t offs, + struct tee_shm *shm, + struct tee_shm **parent_shm) +{ + struct tee_protmem_static_pool *stp = to_protmem_static_pool(pool); + + shm->paddr = stp->pa_base + offs; + *parent_shm = NULL; + + return 0; +} + +static void protmem_pool_op_static_destroy_pool(struct tee_protmem_pool *pool) +{ + struct tee_protmem_static_pool *stp = to_protmem_static_pool(pool); + + gen_pool_destroy(stp->gen_pool); + kfree(stp); +} + +static struct tee_protmem_pool_ops protmem_pool_ops_static = { + .alloc = protmem_pool_op_static_alloc, + .free = protmem_pool_op_static_free, + .update_shm = protmem_pool_op_static_update_shm, + .destroy_pool = protmem_pool_op_static_destroy_pool, +}; + +struct tee_protmem_pool *tee_protmem_static_pool_alloc(phys_addr_t paddr, + size_t size) +{ + const size_t page_mask = PAGE_SIZE - 1; + struct tee_protmem_static_pool *stp; + int rc; + + /* Check it's page aligned */ + if ((paddr | size) & page_mask) + return ERR_PTR(-EINVAL); + + if (!pfn_valid(PHYS_PFN(paddr))) + return ERR_PTR(-EINVAL); + + stp = kzalloc(sizeof(*stp), GFP_KERNEL); + if (!stp) + return ERR_PTR(-ENOMEM); + + stp->gen_pool = gen_pool_create(PAGE_SHIFT, -1); + if (!stp->gen_pool) { + rc = -ENOMEM; + goto err_free; + } + + rc = gen_pool_add(stp->gen_pool, paddr, size, -1); + if (rc) + goto err_free_pool; + + stp->pool.ops = &protmem_pool_ops_static; + stp->pa_base = paddr; + return &stp->pool; + +err_free_pool: + gen_pool_destroy(stp->gen_pool); +err_free: + kfree(stp); + + return ERR_PTR(rc); +} +EXPORT_SYMBOL_GPL(tee_protmem_static_pool_alloc); |