diff options
Diffstat (limited to 'drivers/tee/tee_shm_pool.c')
-rw-r--r-- | drivers/tee/tee_shm_pool.c | 156 |
1 files changed, 156 insertions, 0 deletions
diff --git a/drivers/tee/tee_shm_pool.c b/drivers/tee/tee_shm_pool.c new file mode 100644 index 000000000000..fb4f8522a526 --- /dev/null +++ b/drivers/tee/tee_shm_pool.c @@ -0,0 +1,156 @@ +/* + * Copyright (c) 2015, Linaro Limited + * + * This software is licensed under the terms of the GNU General Public + * License version 2, as published by the Free Software Foundation, and + * may be copied, distributed, and modified under those terms. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + */ +#include <linux/device.h> +#include <linux/dma-buf.h> +#include <linux/genalloc.h> +#include <linux/slab.h> +#include <linux/tee_drv.h> +#include "tee_private.h" + +static int pool_op_gen_alloc(struct tee_shm_pool_mgr *poolm, + struct tee_shm *shm, size_t size) +{ + unsigned long va; + struct gen_pool *genpool = poolm->private_data; + size_t s = roundup(size, 1 << genpool->min_alloc_order); + + va = gen_pool_alloc(genpool, s); + if (!va) + return -ENOMEM; + + memset((void *)va, 0, s); + shm->kaddr = (void *)va; + shm->paddr = gen_pool_virt_to_phys(genpool, va); + shm->size = s; + return 0; +} + +static void pool_op_gen_free(struct tee_shm_pool_mgr *poolm, + struct tee_shm *shm) +{ + gen_pool_free(poolm->private_data, (unsigned long)shm->kaddr, + shm->size); + shm->kaddr = NULL; +} + +static const struct tee_shm_pool_mgr_ops pool_ops_generic = { + .alloc = pool_op_gen_alloc, + .free = pool_op_gen_free, +}; + +static void pool_res_mem_destroy(struct tee_shm_pool *pool) +{ + gen_pool_destroy(pool->private_mgr.private_data); + gen_pool_destroy(pool->dma_buf_mgr.private_data); +} + +static int pool_res_mem_mgr_init(struct tee_shm_pool_mgr *mgr, + struct tee_shm_pool_mem_info *info, + int min_alloc_order) +{ + size_t page_mask = PAGE_SIZE - 1; + struct gen_pool *genpool = NULL; + int rc; + + /* + * Start and end must be page aligned + */ + if ((info->vaddr & page_mask) || (info->paddr & page_mask) || + (info->size & page_mask)) + return -EINVAL; + + genpool = gen_pool_create(min_alloc_order, -1); + if (!genpool) + return -ENOMEM; + + gen_pool_set_algo(genpool, gen_pool_best_fit, NULL); + rc = gen_pool_add_virt(genpool, info->vaddr, info->paddr, info->size, + -1); + if (rc) { + gen_pool_destroy(genpool); + return rc; + } + + mgr->private_data = genpool; + mgr->ops = &pool_ops_generic; + return 0; +} + +/** + * tee_shm_pool_alloc_res_mem() - Create a shared memory pool from reserved + * memory range + * @priv_info: Information for driver private shared memory pool + * @dmabuf_info: Information for dma-buf shared memory pool + * + * Start and end of pools will must be page aligned. + * + * Allocation with the flag TEE_SHM_DMA_BUF set will use the range supplied + * in @dmabuf, others will use the range provided by @priv. + * + * @returns pointer to a 'struct tee_shm_pool' or an ERR_PTR on failure. + */ +struct tee_shm_pool * +tee_shm_pool_alloc_res_mem(struct tee_shm_pool_mem_info *priv_info, + struct tee_shm_pool_mem_info *dmabuf_info) +{ + struct tee_shm_pool *pool = NULL; + int ret; + + pool = kzalloc(sizeof(*pool), GFP_KERNEL); + if (!pool) { + ret = -ENOMEM; + goto err; + } + + /* + * Create the pool for driver private shared memory + */ + ret = pool_res_mem_mgr_init(&pool->private_mgr, priv_info, + 3 /* 8 byte aligned */); + if (ret) + goto err; + + /* + * Create the pool for dma_buf shared memory + */ + ret = pool_res_mem_mgr_init(&pool->dma_buf_mgr, dmabuf_info, + PAGE_SHIFT); + if (ret) + goto err; + + pool->destroy = pool_res_mem_destroy; + return pool; +err: + if (ret == -ENOMEM) + pr_err("%s: can't allocate memory for res_mem shared memory pool\n", __func__); + if (pool && pool->private_mgr.private_data) + gen_pool_destroy(pool->private_mgr.private_data); + kfree(pool); + return ERR_PTR(ret); +} +EXPORT_SYMBOL_GPL(tee_shm_pool_alloc_res_mem); + +/** + * tee_shm_pool_free() - Free a shared memory pool + * @pool: The shared memory pool to free + * + * There must be no remaining shared memory allocated from this pool when + * this function is called. + */ +void tee_shm_pool_free(struct tee_shm_pool *pool) +{ + pool->destroy(pool); + kfree(pool); +} +EXPORT_SYMBOL_GPL(tee_shm_pool_free); |