/* SPDX-License-Identifier: GPL-2.0 OR MIT */
/*
 * Copyright 2021 VMware, Inc.
 *
 * 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 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 "vmwgfx_drv.h"

#include "drm/drm_prime.h"
#include "drm/drm_gem_ttm_helper.h"

/**
 * vmw_buffer_object - Convert a struct ttm_buffer_object to a struct
 * vmw_buffer_object.
 *
 * @bo: Pointer to the TTM buffer object.
 * Return: Pointer to the struct vmw_buffer_object embedding the
 * TTM buffer object.
 */
static struct vmw_buffer_object *
vmw_buffer_object(struct ttm_buffer_object *bo)
{
        return container_of(bo, struct vmw_buffer_object, base);
}

static void vmw_gem_object_free(struct drm_gem_object *gobj)
{
        struct ttm_buffer_object *bo = drm_gem_ttm_of_gem(gobj);
        if (bo) {
                ttm_bo_put(bo);
        }
}

static int vmw_gem_object_open(struct drm_gem_object *obj,
                               struct drm_file *file_priv)
{
        return 0;
}

static void vmw_gem_object_close(struct drm_gem_object *obj,
                                 struct drm_file *file_priv)
{
}

static int vmw_gem_pin_private(struct drm_gem_object *obj, bool do_pin)
{
        struct ttm_buffer_object *bo = drm_gem_ttm_of_gem(obj);
        struct vmw_buffer_object *vbo = vmw_buffer_object(bo);
        int ret;

        ret = ttm_bo_reserve(bo, false, false, NULL);
        if (unlikely(ret != 0))
                goto err;

        vmw_bo_pin_reserved(vbo, do_pin);

        ttm_bo_unreserve(bo);

err:
        return ret;
}


static int vmw_gem_object_pin(struct drm_gem_object *obj)
{
        return vmw_gem_pin_private(obj, true);
}

static void vmw_gem_object_unpin(struct drm_gem_object *obj)
{
        vmw_gem_pin_private(obj, false);
}

static struct sg_table *vmw_gem_object_get_sg_table(struct drm_gem_object *obj)
{
        struct ttm_buffer_object *bo = drm_gem_ttm_of_gem(obj);
        struct vmw_ttm_tt *vmw_tt =
                container_of(bo->ttm, struct vmw_ttm_tt, dma_ttm);

        if (vmw_tt->vsgt.sgt)
                return vmw_tt->vsgt.sgt;

        return drm_prime_pages_to_sg(obj->dev, vmw_tt->dma_ttm.pages, vmw_tt->dma_ttm.num_pages);
}


static const struct drm_gem_object_funcs vmw_gem_object_funcs = {
        .free = vmw_gem_object_free,
        .open = vmw_gem_object_open,
        .close = vmw_gem_object_close,
        .print_info = drm_gem_ttm_print_info,
        .pin = vmw_gem_object_pin,
        .unpin = vmw_gem_object_unpin,
        .get_sg_table = vmw_gem_object_get_sg_table,
        .vmap = drm_gem_ttm_vmap,
        .vunmap = drm_gem_ttm_vunmap,
        .mmap = drm_gem_ttm_mmap,
};

/**
 * vmw_gem_destroy - vmw buffer object destructor
 *
 * @bo: Pointer to the embedded struct ttm_buffer_object
 */
void vmw_gem_destroy(struct ttm_buffer_object *bo)
{
        struct vmw_buffer_object *vbo = vmw_buffer_object(bo);

        WARN_ON(vbo->dirty);
        WARN_ON(!RB_EMPTY_ROOT(&vbo->res_tree));
        vmw_bo_unmap(vbo);
        drm_gem_object_release(&vbo->base.base);
        kfree(vbo);
}

int vmw_gem_object_create_with_handle(struct vmw_private *dev_priv,
                                      struct drm_file *filp,
                                      uint32_t size,
                                      uint32_t *handle,
                                      struct vmw_buffer_object **p_vbo)
{
        int ret;

        ret = vmw_bo_create(dev_priv, size,
                            (dev_priv->has_mob) ?
                                    &vmw_sys_placement :
                                    &vmw_vram_sys_placement,
                            true, false, &vmw_gem_destroy, p_vbo);

        (*p_vbo)->base.base.funcs = &vmw_gem_object_funcs;
        if (ret != 0)
                goto out_no_bo;

        ret = drm_gem_handle_create(filp, &(*p_vbo)->base.base, handle);
        /* drop reference from allocate - handle holds it now */
        drm_gem_object_put(&(*p_vbo)->base.base);
out_no_bo:
        return ret;
}


int vmw_gem_object_create_ioctl(struct drm_device *dev, void *data,
                                struct drm_file *filp)
{
        struct vmw_private *dev_priv = vmw_priv(dev);
        union drm_vmw_alloc_dmabuf_arg *arg =
            (union drm_vmw_alloc_dmabuf_arg *)data;
        struct drm_vmw_alloc_dmabuf_req *req = &arg->req;
        struct drm_vmw_dmabuf_rep *rep = &arg->rep;
        struct vmw_buffer_object *vbo;
        uint32_t handle;
        int ret;

        ret = vmw_gem_object_create_with_handle(dev_priv, filp,
                                                req->size, &handle, &vbo);
        if (ret)
                goto out_no_bo;

        rep->handle = handle;
        rep->map_handle = drm_vma_node_offset_addr(&vbo->base.base.vma_node);
        rep->cur_gmr_id = handle;
        rep->cur_gmr_offset = 0;
out_no_bo:
        return ret;
}

#if defined(CONFIG_DEBUG_FS)

static void vmw_bo_print_info(int id, struct vmw_buffer_object *bo, struct seq_file *m)
{
        const char *placement;
        const char *type;

        switch (bo->base.resource->mem_type) {
        case TTM_PL_SYSTEM:
                placement = " CPU";
                break;
        case VMW_PL_GMR:
                placement = " GMR";
                break;
        case VMW_PL_MOB:
                placement = " MOB";
                break;
        case VMW_PL_SYSTEM:
                placement = "VCPU";
                break;
        case TTM_PL_VRAM:
                placement = "VRAM";
                break;
        default:
                placement = "None";
                break;
        }

        switch (bo->base.type) {
        case ttm_bo_type_device:
                type = "device";
                break;
        case ttm_bo_type_kernel:
                type = "kernel";
                break;
        case ttm_bo_type_sg:
                type = "sg    ";
                break;
        default:
                type = "none  ";
                break;
        }

        seq_printf(m, "\t\t0x%08x: %12zu bytes %s, type = %s",
                   id, bo->base.base.size, placement, type);
        seq_printf(m, ", priority = %u, pin_count = %u, GEM refs = %d, TTM refs = %d",
                   bo->base.priority,
                   bo->base.pin_count,
                   kref_read(&bo->base.base.refcount),
                   kref_read(&bo->base.kref));
        seq_puts(m, "\n");
}

static int vmw_debugfs_gem_info_show(struct seq_file *m, void *unused)
{
        struct vmw_private *vdev = (struct vmw_private *)m->private;
        struct drm_device *dev = &vdev->drm;
        struct drm_file *file;
        int r;

        r = mutex_lock_interruptible(&dev->filelist_mutex);
        if (r)
                return r;

        list_for_each_entry(file, &dev->filelist, lhead) {
                struct task_struct *task;
                struct drm_gem_object *gobj;
                int id;

                /*
                 * Although we have a valid reference on file->pid, that does
                 * not guarantee that the task_struct who called get_pid() is
                 * still alive (e.g. get_pid(current) => fork() => exit()).
                 * Therefore, we need to protect this ->comm access using RCU.
                 */
                rcu_read_lock();
                task = pid_task(file->pid, PIDTYPE_PID);
                seq_printf(m, "pid %8d command %s:\n", pid_nr(file->pid),
                           task ? task->comm : "<unknown>");
                rcu_read_unlock();

                spin_lock(&file->table_lock);
                idr_for_each_entry(&file->object_idr, gobj, id) {
                        struct vmw_buffer_object *bo = gem_to_vmw_bo(gobj);

                        vmw_bo_print_info(id, bo, m);
                }
                spin_unlock(&file->table_lock);
        }

        mutex_unlock(&dev->filelist_mutex);
        return 0;
}

DEFINE_SHOW_ATTRIBUTE(vmw_debugfs_gem_info);

#endif

void vmw_debugfs_gem_init(struct vmw_private *vdev)
{
#if defined(CONFIG_DEBUG_FS)
        struct drm_minor *minor = vdev->drm.primary;
        struct dentry *root = minor->debugfs_root;

        debugfs_create_file("vmwgfx_gem_info", 0444, root, vdev,
                            &vmw_debugfs_gem_info_fops);
#endif
}