drivers/tee/tee_shm_pool.c

0001 // SPDX-License-Identifier: GPL-2.0-only
0002 /*
0003  * Copyright (c) 2015, 2017, 2022 Linaro Limited
0004  */
0005 #include <linux/device.h>
0006 #include <linux/dma-buf.h>
0007 #include <linux/genalloc.h>
0008 #include <linux/slab.h>
0009 #include <linux/tee_drv.h>
0010 #include "tee_private.h"
0011
0012 static int pool_op_gen_alloc(struct tee_shm_pool *pool, struct tee_shm *shm,
0013                  size_t size, size_t align)
0014 {
0015     unsigned long va;
0016     struct gen_pool *genpool = pool->private_data;
0017     size_t a = max_t(size_t, align, BIT(genpool->min_alloc_order));
0018     struct genpool_data_align data = { .align = a };
0019     size_t s = roundup(size, a);
0020
0021     va = gen_pool_alloc_algo(genpool, s, gen_pool_first_fit_align, &data);
0022     if (!va)
0023         return -ENOMEM;
0024
0025     memset((void *)va, 0, s);
0026     shm->kaddr = (void *)va;
0027     shm->paddr = gen_pool_virt_to_phys(genpool, va);
0028     shm->size = s;
0029     /*
0030      * This is from a static shared memory pool so no need to register
0031      * each chunk, and no need to unregister later either.
0032      */
0033     shm->flags &= ~TEE_SHM_DYNAMIC;
0034     return 0;
0035 }
0036
0037 static void pool_op_gen_free(struct tee_shm_pool *pool, struct tee_shm *shm)
0038 {
0039     gen_pool_free(pool->private_data, (unsigned long)shm->kaddr,
0040               shm->size);
0041     shm->kaddr = NULL;
0042 }
0043
0044 static void pool_op_gen_destroy_pool(struct tee_shm_pool *pool)
0045 {
0046     gen_pool_destroy(pool->private_data);
0047     kfree(pool);
0048 }
0049
0050 static const struct tee_shm_pool_ops pool_ops_generic = {
0051     .alloc = pool_op_gen_alloc,
0052     .free = pool_op_gen_free,
0053     .destroy_pool = pool_op_gen_destroy_pool,
0054 };
0055
0056 struct tee_shm_pool *tee_shm_pool_alloc_res_mem(unsigned long vaddr,
0057                         phys_addr_t paddr, size_t size,
0058                         int min_alloc_order)
0059 {
0060     const size_t page_mask = PAGE_SIZE - 1;
0061     struct tee_shm_pool *pool;
0062     int rc;
0063
0064     /* Start and end must be page aligned */
0065     if (vaddr & page_mask || paddr & page_mask || size & page_mask)
0066         return ERR_PTR(-EINVAL);
0067
0068     pool = kzalloc(sizeof(*pool), GFP_KERNEL);
0069     if (!pool)
0070         return ERR_PTR(-ENOMEM);
0071
0072     pool->private_data = gen_pool_create(min_alloc_order, -1);
0073     if (!pool->private_data) {
0074         rc = -ENOMEM;
0075         goto err;
0076     }
0077
0078     rc = gen_pool_add_virt(pool->private_data, vaddr, paddr, size, -1);
0079     if (rc) {
0080         gen_pool_destroy(pool->private_data);
0081         goto err;
0082     }
0083
0084     pool->ops = &pool_ops_generic;
0085
0086     return pool;
0087 err:
0088     kfree(pool);
0089
0090     return ERR_PTR(rc);
0091 }
0092 EXPORT_SYMBOL_GPL(tee_shm_pool_alloc_res_mem);