On 28/08/2023 21:25, Bartosz Golaszewski wrote: > +/** > + * qcom_shm_bridge_pool_new - Create a new SHM Bridge memory pool. > + * > + * @size: Size of the pool. > + * > + * Creates a new Shared Memory Bridge pool from which users can allocate memory > + * chunks. Must be called from process context. > + * > + * Return: > + * Pointer to the newly created SHM Bridge pool with reference count set to 1 > + * or ERR_PTR(). > + */ > +struct qcom_shm_bridge_pool *qcom_shm_bridge_pool_new(size_t size) > +{ > + struct device *dev; > + > + dev = bus_find_device_by_name(&platform_bus_type, NULL, > + "qcom-shm-bridge"); > + if (!dev) > + return ERR_PTR(-ENODEV); > + > + return qcom_shm_bridge_pool_new_for_dev(dev, size); > +} > +EXPORT_SYMBOL_GPL(qcom_shm_bridge_pool_new); I do not see an user of this. Do not add exported symbols without users. Drop export. I would even suggest drop the function entirely, why do we need dead code? > + > +/** > + * qcom_shm_bridge_pool_ref - Increate the refcount of an SHM Bridge pool. > + * > + * @pool: SHM Bridge pool of which the reference count to increase. > + * > + * Return: > + * Pointer to the same pool object. > + */ > +struct qcom_shm_bridge_pool * > +qcom_shm_bridge_pool_ref(struct qcom_shm_bridge_pool *pool) > +{ > + kref_get(&pool->refcount); > + > + return pool; > +} > +EXPORT_SYMBOL_GPL(qcom_shm_bridge_pool_ref); Ditto > + > +/** > + * qcom_shm_bridge_pool_unref - Decrease the refcount of an SHM Bridge pool. > + * > + * @pool: SHM Bridge pool of which the reference count to decrease. > + * > + * Once the reference count reaches 0, the pool is released. > + */ > +void qcom_shm_bridge_pool_unref(struct qcom_shm_bridge_pool *pool) > +{ > + kref_put(&pool->refcount, qcom_shm_bridge_pool_release); > +} > +EXPORT_SYMBOL_GPL(qcom_shm_bridge_pool_unref); Ditto > + > +static void devm_qcom_shm_bridge_pool_unref(void *data) > +{ > + struct qcom_shm_bridge_pool *pool = data; > + > + qcom_shm_bridge_pool_unref(pool); > +} > + > +/** > + * devm_qcom_shm_bridge_pool_new - Managed variant of qcom_shm_bridge_pool_new. > + * > + * @dev: Device for which to map memory and which will manage this pool. > + * @size: Size of the pool. > + * > + * Return: > + * Pointer to the newly created SHM Bridge pool with reference count set to 1 > + * or ERR_PTR(). > + */ > +struct qcom_shm_bridge_pool * > +devm_qcom_shm_bridge_pool_new(struct device *dev, size_t size) > +{ > + struct qcom_shm_bridge_pool *pool; > + int ret; > + > + pool = qcom_shm_bridge_pool_new(size); > + if (IS_ERR(pool)) > + return pool; > + > + ret = devm_add_action_or_reset(dev, devm_qcom_shm_bridge_pool_unref, > + pool); > + if (ret) > + return ERR_PTR(ret); > + > + return pool; > +} > +EXPORT_SYMBOL_GPL(devm_qcom_shm_bridge_pool_new); Ditto > + > +/** > + * qcom_shm_bridge_alloc - Allocate a chunk of memory from an SHM Bridge pool. > + * > + * @pool: Pool to allocate memory from. May be NULL. > + * @size: Number of bytes to allocate. > + * @gfp: Allocation flags. > + * > + * If pool is NULL then the global fall-back pool is used. > + * > + * Return: > + * Virtual address of the allocated memory or ERR_PTR(). Must be freed using > + * qcom_shm_bridge_free(). > + */ > +void *qcom_shm_bridge_alloc(struct qcom_shm_bridge_pool *pool, > + size_t size, gfp_t gfp) > +{ > + struct qcom_shm_bridge_chunk *chunk __free(kfree) = NULL; > + unsigned long vaddr; > + int ret; ... > + > + return no_free_ptr(chunk)->vaddr; > +} > +EXPORT_SYMBOL_GPL(qcom_shm_bridge_alloc); > + > +/** > + * qcom_shm_bridge_free - Free SHM Bridge memory allocated from the pool. > + * > + * @vaddr: Virtual address of the allocated memory to free. > + */ > +void qcom_shm_bridge_free(void *vaddr) > +{ > + struct qcom_shm_bridge_chunk *chunk; > + struct qcom_shm_bridge_pool *pool; > + > + scoped_guard(spinlock_irqsave, &qcom_shm_bridge_chunks_lock) > + chunk = radix_tree_delete_item(&qcom_shm_bridge_chunks, > + (unsigned long)vaddr, NULL); > + if (!chunk) > + goto out_warn; > + > + pool = chunk->parent; > + > + guard(spinlock_irqsave)(&pool->lock); > + > + list_for_each_entry(chunk, &pool->chunks, siblings) { > + if (vaddr != chunk->vaddr) > + continue; > + > + gen_pool_free(pool->genpool, (unsigned long)chunk->vaddr, > + chunk->size); > + list_del(&chunk->siblings); > + qcom_shm_bridge_pool_unref(pool); > + kfree(chunk); > + return; > + } > + > +out_warn: > + WARN(1, "Virtual address %p not allocated for SHM bridge", vaddr); > +} > +EXPORT_SYMBOL_GPL(qcom_shm_bridge_free); > + ... > +phys_addr_t qcom_shm_bridge_to_phys_addr(void *vaddr) > +{ > + struct qcom_shm_bridge_chunk *chunk; > + struct qcom_shm_bridge_pool *pool; > + > + guard(spinlock_irqsave)(&qcom_shm_bridge_chunks_lock); > + > + chunk = radix_tree_lookup(&qcom_shm_bridge_chunks, > + (unsigned long)vaddr); > + if (!chunk) > + return 0; > + > + pool = chunk->parent; > + > + guard(spinlock_irqsave)(&pool->lock); > + > + return gen_pool_virt_to_phys(pool->genpool, (unsigned long)vaddr); > +} > +EXPORT_SYMBOL_GPL(qcom_shm_bridge_to_phys_addr); Ditto Best regards, Krzysztof