/*
 * Copyright © 2016 Intel Corporation
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice (including the next
 * paragraph) shall be included in all copies or substantial portions of the
 * Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
 * IN THE SOFTWARE.
 *
 */

#include "gem/i915_gem_pm.h"
#include "gem/selftests/igt_gem_utils.h"
#include "gem/selftests/mock_context.h"
#include "gt/intel_gt.h"

#include "i915_selftest.h"

#include "igt_flush_test.h"
#include "lib_sw_fence.h"
#include "mock_drm.h"
#include "mock_gem_device.h"

static void quirk_add(struct drm_i915_gem_object *obj,
                      struct list_head *objects)
{
        /* quirk is only for live tiled objects, use it to declare ownership */
        GEM_BUG_ON(i915_gem_object_has_tiling_quirk(obj));
        i915_gem_object_set_tiling_quirk(obj);
        list_add(&obj->st_link, objects);
}

static int populate_ggtt(struct i915_ggtt *ggtt, struct list_head *objects)
{
        struct drm_i915_gem_object *obj;
        unsigned long count;

        count = 0;
        do {
                struct i915_vma *vma;

                obj = i915_gem_object_create_internal(ggtt->vm.i915,
                                                      I915_GTT_PAGE_SIZE);
                if (IS_ERR(obj))
                        return PTR_ERR(obj);

                vma = i915_gem_object_ggtt_pin(obj, NULL, 0, 0, 0);
                if (IS_ERR(vma)) {
                        i915_gem_object_put(obj);
                        if (vma == ERR_PTR(-ENOSPC))
                                break;

                        return PTR_ERR(vma);
                }

                quirk_add(obj, objects);
                count++;
        } while (1);
        pr_debug("Filled GGTT with %lu pages [%llu total]\n",
                 count, ggtt->vm.total / PAGE_SIZE);

        if (list_empty(&ggtt->vm.bound_list)) {
                pr_err("No objects on the GGTT inactive list!\n");
                return -EINVAL;
        }

        return 0;
}

static void unpin_ggtt(struct i915_ggtt *ggtt)
{
        struct i915_vma *vma;

        list_for_each_entry(vma, &ggtt->vm.bound_list, vm_link)
                if (i915_gem_object_has_tiling_quirk(vma->obj))
                        i915_vma_unpin(vma);
}

static void cleanup_objects(struct i915_ggtt *ggtt, struct list_head *list)
{
        struct drm_i915_gem_object *obj, *on;

        list_for_each_entry_safe(obj, on, list, st_link) {
                GEM_BUG_ON(!i915_gem_object_has_tiling_quirk(obj));
                i915_gem_object_set_tiling_quirk(obj);
                i915_gem_object_put(obj);
        }

        i915_gem_drain_freed_objects(ggtt->vm.i915);
}

static int igt_evict_something(void *arg)
{
        struct intel_gt *gt = arg;
        struct i915_ggtt *ggtt = gt->ggtt;
        LIST_HEAD(objects);
        int err;

        /* Fill the GGTT with pinned objects and try to evict one. */

        err = populate_ggtt(ggtt, &objects);
        if (err)
                goto cleanup;

        /* Everything is pinned, nothing should happen */
        mutex_lock(&ggtt->vm.mutex);
        err = i915_gem_evict_something(&ggtt->vm,
                                       I915_GTT_PAGE_SIZE, 0, 0,
                                       0, U64_MAX,
                                       0);
        mutex_unlock(&ggtt->vm.mutex);
        if (err != -ENOSPC) {
                pr_err("i915_gem_evict_something failed on a full GGTT with err=%d\n",
                       err);
                goto cleanup;
        }

        unpin_ggtt(ggtt);

        /* Everything is unpinned, we should be able to evict something */
        mutex_lock(&ggtt->vm.mutex);
        err = i915_gem_evict_something(&ggtt->vm,
                                       I915_GTT_PAGE_SIZE, 0, 0,
                                       0, U64_MAX,
                                       0);
        mutex_unlock(&ggtt->vm.mutex);
        if (err) {
                pr_err("i915_gem_evict_something failed on a full GGTT with err=%d\n",
                       err);
                goto cleanup;
        }

cleanup:
        cleanup_objects(ggtt, &objects);
        return err;
}

static int igt_overcommit(void *arg)
{
        struct intel_gt *gt = arg;
        struct i915_ggtt *ggtt = gt->ggtt;
        struct drm_i915_gem_object *obj;
        struct i915_vma *vma;
        LIST_HEAD(objects);
        int err;

        /* Fill the GGTT with pinned objects and then try to pin one more.
         * We expect it to fail.
         */

        err = populate_ggtt(ggtt, &objects);
        if (err)
                goto cleanup;

        obj = i915_gem_object_create_internal(gt->i915, I915_GTT_PAGE_SIZE);
        if (IS_ERR(obj)) {
                err = PTR_ERR(obj);
                goto cleanup;
        }

        quirk_add(obj, &objects);

        vma = i915_gem_object_ggtt_pin(obj, NULL, 0, 0, 0);
        if (vma != ERR_PTR(-ENOSPC)) {
                pr_err("Failed to evict+insert, i915_gem_object_ggtt_pin returned err=%d\n", (int)PTR_ERR_OR_ZERO(vma));
                err = -EINVAL;
                goto cleanup;
        }

cleanup:
        cleanup_objects(ggtt, &objects);
        return err;
}

static int igt_evict_for_vma(void *arg)
{
        struct intel_gt *gt = arg;
        struct i915_ggtt *ggtt = gt->ggtt;
        struct drm_mm_node target = {
                .start = 0,
                .size = 4096,
        };
        LIST_HEAD(objects);
        int err;

        /* Fill the GGTT with pinned objects and try to evict a range. */

        err = populate_ggtt(ggtt, &objects);
        if (err)
                goto cleanup;

        /* Everything is pinned, nothing should happen */
        mutex_lock(&ggtt->vm.mutex);
        err = i915_gem_evict_for_node(&ggtt->vm, &target, 0);
        mutex_unlock(&ggtt->vm.mutex);
        if (err != -ENOSPC) {
                pr_err("i915_gem_evict_for_node on a full GGTT returned err=%d\n",
                       err);
                goto cleanup;
        }

        unpin_ggtt(ggtt);

        /* Everything is unpinned, we should be able to evict the node */
        mutex_lock(&ggtt->vm.mutex);
        err = i915_gem_evict_for_node(&ggtt->vm, &target, 0);
        mutex_unlock(&ggtt->vm.mutex);
        if (err) {
                pr_err("i915_gem_evict_for_node returned err=%d\n",
                       err);
                goto cleanup;
        }

cleanup:
        cleanup_objects(ggtt, &objects);
        return err;
}

static void mock_color_adjust(const struct drm_mm_node *node,
                              unsigned long color,
                              u64 *start,
                              u64 *end)
{
}

static int igt_evict_for_cache_color(void *arg)
{
        struct intel_gt *gt = arg;
        struct i915_ggtt *ggtt = gt->ggtt;
        const unsigned long flags = PIN_OFFSET_FIXED;
        struct drm_mm_node target = {
                .start = I915_GTT_PAGE_SIZE * 2,
                .size = I915_GTT_PAGE_SIZE,
                .color = I915_CACHE_LLC,
        };
        struct drm_i915_gem_object *obj;
        struct i915_vma *vma;
        LIST_HEAD(objects);
        int err;

        /*
         * Currently the use of color_adjust for the GGTT is limited to cache
         * coloring and guard pages, and so the presence of mm.color_adjust for
         * the GGTT is assumed to be i915_ggtt_color_adjust, hence using a mock
         * color adjust will work just fine for our purposes.
         */
        ggtt->vm.mm.color_adjust = mock_color_adjust;
        GEM_BUG_ON(!i915_vm_has_cache_coloring(&ggtt->vm));

        obj = i915_gem_object_create_internal(gt->i915, I915_GTT_PAGE_SIZE);
        if (IS_ERR(obj)) {
                err = PTR_ERR(obj);
                goto cleanup;
        }
        i915_gem_object_set_cache_coherency(obj, I915_CACHE_LLC);
        quirk_add(obj, &objects);

        vma = i915_gem_object_ggtt_pin(obj, NULL, 0, 0,
                                       I915_GTT_PAGE_SIZE | flags);
        if (IS_ERR(vma)) {
                pr_err("[0]i915_gem_object_ggtt_pin failed\n");
                err = PTR_ERR(vma);
                goto cleanup;
        }

        obj = i915_gem_object_create_internal(gt->i915, I915_GTT_PAGE_SIZE);
        if (IS_ERR(obj)) {
                err = PTR_ERR(obj);
                goto cleanup;
        }
        i915_gem_object_set_cache_coherency(obj, I915_CACHE_LLC);
        quirk_add(obj, &objects);

        /* Neighbouring; same colour - should fit */
        vma = i915_gem_object_ggtt_pin(obj, NULL, 0, 0,
                                       (I915_GTT_PAGE_SIZE * 2) | flags);
        if (IS_ERR(vma)) {
                pr_err("[1]i915_gem_object_ggtt_pin failed\n");
                err = PTR_ERR(vma);
                goto cleanup;
        }

        i915_vma_unpin(vma);

        /* Remove just the second vma */
        mutex_lock(&ggtt->vm.mutex);
        err = i915_gem_evict_for_node(&ggtt->vm, &target, 0);
        mutex_unlock(&ggtt->vm.mutex);
        if (err) {
                pr_err("[0]i915_gem_evict_for_node returned err=%d\n", err);
                goto cleanup;
        }

        /* Attempt to remove the first *pinned* vma, by removing the (empty)
         * neighbour -- this should fail.
         */
        target.color = I915_CACHE_L3_LLC;

        mutex_lock(&ggtt->vm.mutex);
        err = i915_gem_evict_for_node(&ggtt->vm, &target, 0);
        mutex_unlock(&ggtt->vm.mutex);
        if (!err) {
                pr_err("[1]i915_gem_evict_for_node returned err=%d\n", err);
                err = -EINVAL;
                goto cleanup;
        }

        err = 0;

cleanup:
        unpin_ggtt(ggtt);
        cleanup_objects(ggtt, &objects);
        ggtt->vm.mm.color_adjust = NULL;
        return err;
}

static int igt_evict_vm(void *arg)
{
        struct intel_gt *gt = arg;
        struct i915_ggtt *ggtt = gt->ggtt;
        LIST_HEAD(objects);
        int err;

        /* Fill the GGTT with pinned objects and try to evict everything. */

        err = populate_ggtt(ggtt, &objects);
        if (err)
                goto cleanup;

        /* Everything is pinned, nothing should happen */
        mutex_lock(&ggtt->vm.mutex);
        err = i915_gem_evict_vm(&ggtt->vm);
        mutex_unlock(&ggtt->vm.mutex);
        if (err) {
                pr_err("i915_gem_evict_vm on a full GGTT returned err=%d]\n",
                       err);
                goto cleanup;
        }

        unpin_ggtt(ggtt);

        mutex_lock(&ggtt->vm.mutex);
        err = i915_gem_evict_vm(&ggtt->vm);
        mutex_unlock(&ggtt->vm.mutex);
        if (err) {
                pr_err("i915_gem_evict_vm on a full GGTT returned err=%d]\n",
                       err);
                goto cleanup;
        }

cleanup:
        cleanup_objects(ggtt, &objects);
        return err;
}

static int igt_evict_contexts(void *arg)
{
        const u64 PRETEND_GGTT_SIZE = 16ull << 20;
        struct intel_gt *gt = arg;
        struct i915_ggtt *ggtt = gt->ggtt;
        struct drm_i915_private *i915 = gt->i915;
        struct intel_engine_cs *engine;
        enum intel_engine_id id;
        struct reserved {
                struct drm_mm_node node;
                struct reserved *next;
        } *reserved = NULL;
        intel_wakeref_t wakeref;
        struct drm_mm_node hole;
        unsigned long count;
        int err;

        /*
         * The purpose of this test is to verify that we will trigger an
         * eviction in the GGTT when constructing a request that requires
         * additional space in the GGTT for pinning the context. This space
         * is not directly tied to the request so reclaiming it requires
         * extra work.
         *
         * As such this test is only meaningful for full-ppgtt environments
         * where the GTT space of the request is separate from the GGTT
         * allocation required to build the request.
         */
        if (!HAS_FULL_PPGTT(i915))
                return 0;

        wakeref = intel_runtime_pm_get(&i915->runtime_pm);

        /* Reserve a block so that we know we have enough to fit a few rq */
        memset(&hole, 0, sizeof(hole));
        mutex_lock(&ggtt->vm.mutex);
        err = i915_gem_gtt_insert(&ggtt->vm, &hole,
                                  PRETEND_GGTT_SIZE, 0, I915_COLOR_UNEVICTABLE,
                                  0, ggtt->vm.total,
                                  PIN_NOEVICT);
        if (err)
                goto out_locked;

        /* Make the GGTT appear small by filling it with unevictable nodes */
        count = 0;
        do {
                struct reserved *r;

                mutex_unlock(&ggtt->vm.mutex);
                r = kcalloc(1, sizeof(*r), GFP_KERNEL);
                mutex_lock(&ggtt->vm.mutex);
                if (!r) {
                        err = -ENOMEM;
                        goto out_locked;
                }

                if (i915_gem_gtt_insert(&ggtt->vm, &r->node,
                                        1ul << 20, 0, I915_COLOR_UNEVICTABLE,
                                        0, ggtt->vm.total,
                                        PIN_NOEVICT)) {
                        kfree(r);
                        break;
                }

                r->next = reserved;
                reserved = r;

                count++;
        } while (1);
        drm_mm_remove_node(&hole);
        mutex_unlock(&ggtt->vm.mutex);
        pr_info("Filled GGTT with %lu 1MiB nodes\n", count);

        /* Overfill the GGTT with context objects and so try to evict one. */
        for_each_engine(engine, gt, id) {
                struct i915_sw_fence fence;

                count = 0;
                onstack_fence_init(&fence);
                do {
                        struct intel_context *ce;
                        struct i915_request *rq;

                        ce = intel_context_create(engine);
                        if (IS_ERR(ce))
                                break;

                        /* We will need some GGTT space for the rq's context */
                        igt_evict_ctl.fail_if_busy = true;
                        rq = intel_context_create_request(ce);
                        igt_evict_ctl.fail_if_busy = false;
                        intel_context_put(ce);

                        if (IS_ERR(rq)) {
                                /* When full, fail_if_busy will trigger EBUSY */
                                if (PTR_ERR(rq) != -EBUSY) {
                                        pr_err("Unexpected error from request alloc (on %s): %d\n",
                                               engine->name,
                                               (int)PTR_ERR(rq));
                                        err = PTR_ERR(rq);
                                }
                                break;
                        }

                        /* Keep every request/ctx pinned until we are full */
                        err = i915_sw_fence_await_sw_fence_gfp(&rq->submit,
                                                               &fence,
                                                               GFP_KERNEL);
                        if (err < 0)
                                break;

                        i915_request_add(rq);
                        count++;
                        err = 0;
                } while(1);
                onstack_fence_fini(&fence);
                pr_info("Submitted %lu contexts/requests on %s\n",
                        count, engine->name);
                if (err)
                        break;
        }

        mutex_lock(&ggtt->vm.mutex);
out_locked:
        if (igt_flush_test(i915))
                err = -EIO;
        while (reserved) {
                struct reserved *next = reserved->next;

                drm_mm_remove_node(&reserved->node);
                kfree(reserved);

                reserved = next;
        }
        if (drm_mm_node_allocated(&hole))
                drm_mm_remove_node(&hole);
        mutex_unlock(&ggtt->vm.mutex);
        intel_runtime_pm_put(&i915->runtime_pm, wakeref);

        return err;
}

int i915_gem_evict_mock_selftests(void)
{
        static const struct i915_subtest tests[] = {
                SUBTEST(igt_evict_something),
                SUBTEST(igt_evict_for_vma),
                SUBTEST(igt_evict_for_cache_color),
                SUBTEST(igt_evict_vm),
                SUBTEST(igt_overcommit),
        };
        struct drm_i915_private *i915;
        intel_wakeref_t wakeref;
        int err = 0;

        i915 = mock_gem_device();
        if (!i915)
                return -ENOMEM;

        with_intel_runtime_pm(&i915->runtime_pm, wakeref)
                err = i915_subtests(tests, &i915->gt);

        mock_destroy_device(i915);
        return err;
}

int i915_gem_evict_live_selftests(struct drm_i915_private *i915)
{
        static const struct i915_subtest tests[] = {
                SUBTEST(igt_evict_contexts),
        };

        if (intel_gt_is_wedged(&i915->gt))
                return 0;

        return intel_gt_live_subtests(tests, &i915->gt);
}