| /* |
| * fence-array: aggregate fences to be waited together |
| * |
| * Copyright (C) 2016 Collabora Ltd |
| * Copyright (C) 2016 Advanced Micro Devices, Inc. |
| * Authors: |
| * Gustavo Padovan <gustavo@padovan.org> |
| * Christian König <christian.koenig@amd.com> |
| * |
| * This program is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License version 2 as published by |
| * the Free Software Foundation. |
| * |
| * 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/export.h> |
| #include <linux/slab.h> |
| #include <linux/fence-array.h> |
| |
| static void fence_array_cb_func(struct fence *f, struct fence_cb *cb); |
| |
| static const char *fence_array_get_driver_name(struct fence *fence) |
| { |
| return "fence_array"; |
| } |
| |
| static const char *fence_array_get_timeline_name(struct fence *fence) |
| { |
| return "unbound"; |
| } |
| |
| static void fence_array_cb_func(struct fence *f, struct fence_cb *cb) |
| { |
| struct fence_array_cb *array_cb = |
| container_of(cb, struct fence_array_cb, cb); |
| struct fence_array *array = array_cb->array; |
| |
| if (atomic_dec_and_test(&array->num_pending)) |
| fence_signal(&array->base); |
| fence_put(&array->base); |
| } |
| |
| static bool fence_array_enable_signaling(struct fence *fence) |
| { |
| struct fence_array *array = to_fence_array(fence); |
| struct fence_array_cb *cb = (void *)(&array[1]); |
| unsigned i; |
| |
| for (i = 0; i < array->num_fences; ++i) { |
| cb[i].array = array; |
| /* |
| * As we may report that the fence is signaled before all |
| * callbacks are complete, we need to take an additional |
| * reference count on the array so that we do not free it too |
| * early. The core fence handling will only hold the reference |
| * until we signal the array as complete (but that is now |
| * insufficient). |
| */ |
| fence_get(&array->base); |
| if (fence_add_callback(array->fences[i], &cb[i].cb, |
| fence_array_cb_func)) { |
| fence_put(&array->base); |
| if (atomic_dec_and_test(&array->num_pending)) |
| return false; |
| } |
| } |
| |
| return true; |
| } |
| |
| static bool fence_array_signaled(struct fence *fence) |
| { |
| struct fence_array *array = to_fence_array(fence); |
| |
| return atomic_read(&array->num_pending) <= 0; |
| } |
| |
| static void fence_array_release(struct fence *fence) |
| { |
| struct fence_array *array = to_fence_array(fence); |
| unsigned i; |
| |
| for (i = 0; i < array->num_fences; ++i) |
| fence_put(array->fences[i]); |
| |
| kfree(array->fences); |
| fence_free(fence); |
| } |
| |
| const struct fence_ops fence_array_ops = { |
| .get_driver_name = fence_array_get_driver_name, |
| .get_timeline_name = fence_array_get_timeline_name, |
| .enable_signaling = fence_array_enable_signaling, |
| .signaled = fence_array_signaled, |
| .wait = fence_default_wait, |
| .release = fence_array_release, |
| }; |
| EXPORT_SYMBOL(fence_array_ops); |
| |
| /** |
| * fence_array_create - Create a custom fence array |
| * @num_fences: [in] number of fences to add in the array |
| * @fences: [in] array containing the fences |
| * @context: [in] fence context to use |
| * @seqno: [in] sequence number to use |
| * @signal_on_any [in] signal on any fence in the array |
| * |
| * Allocate a fence_array object and initialize the base fence with fence_init(). |
| * In case of error it returns NULL. |
| * |
| * The caller should allocte the fences array with num_fences size |
| * and fill it with the fences it wants to add to the object. Ownership of this |
| * array is take and fence_put() is used on each fence on release. |
| * |
| * If @signal_on_any is true the fence array signals if any fence in the array |
| * signals, otherwise it signals when all fences in the array signal. |
| */ |
| struct fence_array *fence_array_create(int num_fences, struct fence **fences, |
| u64 context, unsigned seqno, |
| bool signal_on_any) |
| { |
| struct fence_array *array; |
| size_t size = sizeof(*array); |
| |
| /* Allocate the callback structures behind the array. */ |
| size += num_fences * sizeof(struct fence_array_cb); |
| array = kzalloc(size, GFP_KERNEL); |
| if (!array) |
| return NULL; |
| |
| spin_lock_init(&array->lock); |
| fence_init(&array->base, &fence_array_ops, &array->lock, |
| context, seqno); |
| |
| array->num_fences = num_fences; |
| atomic_set(&array->num_pending, signal_on_any ? 1 : num_fences); |
| array->fences = fences; |
| |
| return array; |
| } |
| EXPORT_SYMBOL(fence_array_create); |