Merge tag 'gpio-v3.13-3' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw...

[linux-2.6.git] / drivers / gpu / drm / vmwgfx / vmwgfx_execbuf.c

/**************************************************************************
 *
 * Copyright © 2009 VMware, Inc., Palo Alto, CA., USA
 * All Rights Reserved.
 *
 * 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, sub license, 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 NON-INFRINGEMENT. IN NO EVENT SHALL
 * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS 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 "vmwgfx_reg.h"
#include <drm/ttm/ttm_bo_api.h>
#include <drm/ttm/ttm_placement.h>

#define VMW_RES_HT_ORDER 12

/**
 * struct vmw_resource_relocation - Relocation info for resources
 *
 * @head: List head for the software context's relocation list.
 * @res: Non-ref-counted pointer to the resource.
 * @offset: Offset of 4 byte entries into the command buffer where the
 * id that needs fixup is located.
 */
struct vmw_resource_relocation {
        struct list_head head;
        const struct vmw_resource *res;
        unsigned long offset;
};

/**
 * struct vmw_resource_val_node - Validation info for resources
 *
 * @head: List head for the software context's resource list.
 * @hash: Hash entry for quick resouce to val_node lookup.
 * @res: Ref-counted pointer to the resource.
 * @switch_backup: Boolean whether to switch backup buffer on unreserve.
 * @new_backup: Refcounted pointer to the new backup buffer.
 * @new_backup_offset: New backup buffer offset if @new_backup is non-NUll.
 * @first_usage: Set to true the first time the resource is referenced in
 * the command stream.
 * @no_buffer_needed: Resources do not need to allocate buffer backup on
 * reservation. The command stream will provide one.
 */
struct vmw_resource_val_node {
        struct list_head head;
        struct drm_hash_item hash;
        struct vmw_resource *res;
        struct vmw_dma_buffer *new_backup;
        unsigned long new_backup_offset;
        bool first_usage;
        bool no_buffer_needed;
};

/**
 * vmw_resource_unreserve - unreserve resources previously reserved for
 * command submission.
 *
 * @list_head: list of resources to unreserve.
 * @backoff: Whether command submission failed.
 */
static void vmw_resource_list_unreserve(struct list_head *list,
                                        bool backoff)
{
        struct vmw_resource_val_node *val;

        list_for_each_entry(val, list, head) {
                struct vmw_resource *res = val->res;
                struct vmw_dma_buffer *new_backup =
                        backoff ? NULL : val->new_backup;

                vmw_resource_unreserve(res, new_backup,
                        val->new_backup_offset);
                vmw_dmabuf_unreference(&val->new_backup);
        }
}


/**
 * vmw_resource_val_add - Add a resource to the software context's
 * resource list if it's not already on it.
 *
 * @sw_context: Pointer to the software context.
 * @res: Pointer to the resource.
 * @p_node On successful return points to a valid pointer to a
 * struct vmw_resource_val_node, if non-NULL on entry.
 */
static int vmw_resource_val_add(struct vmw_sw_context *sw_context,
                                struct vmw_resource *res,
                                struct vmw_resource_val_node **p_node)
{
        struct vmw_resource_val_node *node;
        struct drm_hash_item *hash;
        int ret;

        if (likely(drm_ht_find_item(&sw_context->res_ht, (unsigned long) res,
                                    &hash) == 0)) {
                node = container_of(hash, struct vmw_resource_val_node, hash);
                node->first_usage = false;
                if (unlikely(p_node != NULL))
                        *p_node = node;
                return 0;
        }

        node = kzalloc(sizeof(*node), GFP_KERNEL);
        if (unlikely(node == NULL)) {
                DRM_ERROR("Failed to allocate a resource validation "
                          "entry.\n");
                return -ENOMEM;
        }

        node->hash.key = (unsigned long) res;
        ret = drm_ht_insert_item(&sw_context->res_ht, &node->hash);
        if (unlikely(ret != 0)) {
                DRM_ERROR("Failed to initialize a resource validation "
                          "entry.\n");
                kfree(node);
                return ret;
        }
        list_add_tail(&node->head, &sw_context->resource_list);
        node->res = vmw_resource_reference(res);
        node->first_usage = true;

        if (unlikely(p_node != NULL))
                *p_node = node;

        return 0;
}

/**
 * vmw_resource_relocation_add - Add a relocation to the relocation list
 *
 * @list: Pointer to head of relocation list.
 * @res: The resource.
 * @offset: Offset into the command buffer currently being parsed where the
 * id that needs fixup is located. Granularity is 4 bytes.
 */
static int vmw_resource_relocation_add(struct list_head *list,
                                       const struct vmw_resource *res,
                                       unsigned long offset)
{
        struct vmw_resource_relocation *rel;

        rel = kmalloc(sizeof(*rel), GFP_KERNEL);
        if (unlikely(rel == NULL)) {
                DRM_ERROR("Failed to allocate a resource relocation.\n");
                return -ENOMEM;
        }

        rel->res = res;
        rel->offset = offset;
        list_add_tail(&rel->head, list);

        return 0;
}

/**
 * vmw_resource_relocations_free - Free all relocations on a list
 *
 * @list: Pointer to the head of the relocation list.
 */
static void vmw_resource_relocations_free(struct list_head *list)
{
        struct vmw_resource_relocation *rel, *n;

        list_for_each_entry_safe(rel, n, list, head) {
                list_del(&rel->head);
                kfree(rel);
        }
}

/**
 * vmw_resource_relocations_apply - Apply all relocations on a list
 *
 * @cb: Pointer to the start of the command buffer bein patch. This need
 * not be the same buffer as the one being parsed when the relocation
 * list was built, but the contents must be the same modulo the
 * resource ids.
 * @list: Pointer to the head of the relocation list.
 */
static void vmw_resource_relocations_apply(uint32_t *cb,
                                           struct list_head *list)
{
        struct vmw_resource_relocation *rel;

        list_for_each_entry(rel, list, head)
                cb[rel->offset] = rel->res->id;
}

static int vmw_cmd_invalid(struct vmw_private *dev_priv,
                           struct vmw_sw_context *sw_context,
                           SVGA3dCmdHeader *header)
{
        return capable(CAP_SYS_ADMIN) ? : -EINVAL;
}

static int vmw_cmd_ok(struct vmw_private *dev_priv,
                      struct vmw_sw_context *sw_context,
                      SVGA3dCmdHeader *header)
{
        return 0;
}

/**
 * vmw_bo_to_validate_list - add a bo to a validate list
 *
 * @sw_context: The software context used for this command submission batch.
 * @bo: The buffer object to add.
 * @p_val_node: If non-NULL Will be updated with the validate node number
 * on return.
 *
 * Returns -EINVAL if the limit of number of buffer objects per command
 * submission is reached.
 */
static int vmw_bo_to_validate_list(struct vmw_sw_context *sw_context,
                                   struct ttm_buffer_object *bo,
                                   uint32_t *p_val_node)
{
        uint32_t val_node;
        struct vmw_validate_buffer *vval_buf;
        struct ttm_validate_buffer *val_buf;
        struct drm_hash_item *hash;
        int ret;

        if (likely(drm_ht_find_item(&sw_context->res_ht, (unsigned long) bo,
                                    &hash) == 0)) {
                vval_buf = container_of(hash, struct vmw_validate_buffer,
                                        hash);
                val_buf = &vval_buf->base;
                val_node = vval_buf - sw_context->val_bufs;
        } else {
                val_node = sw_context->cur_val_buf;
                if (unlikely(val_node >= VMWGFX_MAX_VALIDATIONS)) {
                        DRM_ERROR("Max number of DMA buffers per submission "
                                  "exceeded.\n");
                        return -EINVAL;
                }
                vval_buf = &sw_context->val_bufs[val_node];
                vval_buf->hash.key = (unsigned long) bo;
                ret = drm_ht_insert_item(&sw_context->res_ht, &vval_buf->hash);
                if (unlikely(ret != 0)) {
                        DRM_ERROR("Failed to initialize a buffer validation "
                                  "entry.\n");
                        return ret;
                }
                ++sw_context->cur_val_buf;
                val_buf = &vval_buf->base;
                val_buf->bo = ttm_bo_reference(bo);
                val_buf->reserved = false;
                list_add_tail(&val_buf->head, &sw_context->validate_nodes);
        }

        sw_context->fence_flags |= DRM_VMW_FENCE_FLAG_EXEC;

        if (p_val_node)
                *p_val_node = val_node;

        return 0;
}

/**
 * vmw_resources_reserve - Reserve all resources on the sw_context's
 * resource list.
 *
 * @sw_context: Pointer to the software context.
 *
 * Note that since vmware's command submission currently is protected by
 * the cmdbuf mutex, no fancy deadlock avoidance is required for resources,
 * since only a single thread at once will attempt this.
 */
static int vmw_resources_reserve(struct vmw_sw_context *sw_context)
{
        struct vmw_resource_val_node *val;
        int ret;

        list_for_each_entry(val, &sw_context->resource_list, head) {
                struct vmw_resource *res = val->res;

                ret = vmw_resource_reserve(res, val->no_buffer_needed);
                if (unlikely(ret != 0))
                        return ret;

                if (res->backup) {
                        struct ttm_buffer_object *bo = &res->backup->base;

                        ret = vmw_bo_to_validate_list
                                (sw_context, bo, NULL);

                        if (unlikely(ret != 0))
                                return ret;
                }
        }
        return 0;
}

/**
 * vmw_resources_validate - Validate all resources on the sw_context's
 * resource list.
 *
 * @sw_context: Pointer to the software context.
 *
 * Before this function is called, all resource backup buffers must have
 * been validated.
 */
static int vmw_resources_validate(struct vmw_sw_context *sw_context)
{
        struct vmw_resource_val_node *val;
        int ret;

        list_for_each_entry(val, &sw_context->resource_list, head) {
                struct vmw_resource *res = val->res;

                ret = vmw_resource_validate(res);
                if (unlikely(ret != 0)) {
                        if (ret != -ERESTARTSYS)
                                DRM_ERROR("Failed to validate resource.\n");
                        return ret;
                }
        }
        return 0;
}

/**
 * vmw_cmd_res_check - Check that a resource is present and if so, put it
 * on the resource validate list unless it's already there.
 *
 * @dev_priv: Pointer to a device private structure.
 * @sw_context: Pointer to the software context.
 * @res_type: Resource type.
 * @converter: User-space visisble type specific information.
 * @id: Pointer to the location in the command buffer currently being
 * parsed from where the user-space resource id handle is located.
 */
static int vmw_cmd_res_check(struct vmw_private *dev_priv,
                             struct vmw_sw_context *sw_context,
                             enum vmw_res_type res_type,
                             const struct vmw_user_resource_conv *converter,
                             uint32_t *id,
                             struct vmw_resource_val_node **p_val)
{
        struct vmw_res_cache_entry *rcache =
                &sw_context->res_cache[res_type];
        struct vmw_resource *res;
        struct vmw_resource_val_node *node;
        int ret;

        if (*id == SVGA3D_INVALID_ID)
                return 0;

        /*
         * Fastpath in case of repeated commands referencing the same
         * resource
         */

        if (likely(rcache->valid && *id == rcache->handle)) {
                const struct vmw_resource *res = rcache->res;

                rcache->node->first_usage = false;
                if (p_val)
                        *p_val = rcache->node;

                return vmw_resource_relocation_add
                        (&sw_context->res_relocations, res,
                         id - sw_context->buf_start);
        }

        ret = vmw_user_resource_lookup_handle(dev_priv,
                                              sw_context->tfile,
                                              *id,
                                              converter,
                                              &res);
        if (unlikely(ret != 0)) {
                DRM_ERROR("Could not find or use resource 0x%08x.\n",
                          (unsigned) *id);
                dump_stack();
                return ret;
        }

        rcache->valid = true;
        rcache->res = res;
        rcache->handle = *id;

        ret = vmw_resource_relocation_add(&sw_context->res_relocations,
                                          res,
                                          id - sw_context->buf_start);
        if (unlikely(ret != 0))
                goto out_no_reloc;

        ret = vmw_resource_val_add(sw_context, res, &node);
        if (unlikely(ret != 0))
                goto out_no_reloc;

        rcache->node = node;
        if (p_val)
                *p_val = node;
        vmw_resource_unreference(&res);
        return 0;

out_no_reloc:
        BUG_ON(sw_context->error_resource != NULL);
        sw_context->error_resource = res;

        return ret;
}

/**
 * vmw_cmd_cid_check - Check a command header for valid context information.
 *
 * @dev_priv: Pointer to a device private structure.
 * @sw_context: Pointer to the software context.
 * @header: A command header with an embedded user-space context handle.
 *
 * Convenience function: Call vmw_cmd_res_check with the user-space context
 * handle embedded in @header.
 */
static int vmw_cmd_cid_check(struct vmw_private *dev_priv,
                             struct vmw_sw_context *sw_context,
                             SVGA3dCmdHeader *header)
{
        struct vmw_cid_cmd {
                SVGA3dCmdHeader header;
                __le32 cid;
        } *cmd;

        cmd = container_of(header, struct vmw_cid_cmd, header);
        return vmw_cmd_res_check(dev_priv, sw_context, vmw_res_context,
                                 user_context_converter, &cmd->cid, NULL);
}

static int vmw_cmd_set_render_target_check(struct vmw_private *dev_priv,
                                           struct vmw_sw_context *sw_context,
                                           SVGA3dCmdHeader *header)
{
        struct vmw_sid_cmd {
                SVGA3dCmdHeader header;
                SVGA3dCmdSetRenderTarget body;
        } *cmd;
        int ret;

        ret = vmw_cmd_cid_check(dev_priv, sw_context, header);
        if (unlikely(ret != 0))
                return ret;

        cmd = container_of(header, struct vmw_sid_cmd, header);
        ret = vmw_cmd_res_check(dev_priv, sw_context, vmw_res_surface,
                                user_surface_converter,
                                &cmd->body.target.sid, NULL);
        return ret;
}

static int vmw_cmd_surface_copy_check(struct vmw_private *dev_priv,
                                      struct vmw_sw_context *sw_context,
                                      SVGA3dCmdHeader *header)
{
        struct vmw_sid_cmd {
                SVGA3dCmdHeader header;
                SVGA3dCmdSurfaceCopy body;
        } *cmd;
        int ret;

        cmd = container_of(header, struct vmw_sid_cmd, header);
        ret = vmw_cmd_res_check(dev_priv, sw_context, vmw_res_surface,
                                user_surface_converter,
                                &cmd->body.src.sid, NULL);
        if (unlikely(ret != 0))
                return ret;
        return vmw_cmd_res_check(dev_priv, sw_context, vmw_res_surface,
                                 user_surface_converter,
                                 &cmd->body.dest.sid, NULL);
}

static int vmw_cmd_stretch_blt_check(struct vmw_private *dev_priv,
                                     struct vmw_sw_context *sw_context,
                                     SVGA3dCmdHeader *header)
{
        struct vmw_sid_cmd {
                SVGA3dCmdHeader header;
                SVGA3dCmdSurfaceStretchBlt body;
        } *cmd;
        int ret;

        cmd = container_of(header, struct vmw_sid_cmd, header);
        ret = vmw_cmd_res_check(dev_priv, sw_context, vmw_res_surface,
                                user_surface_converter,
                                &cmd->body.src.sid, NULL);
        if (unlikely(ret != 0))
                return ret;
        return vmw_cmd_res_check(dev_priv, sw_context, vmw_res_surface,
                                 user_surface_converter,
                                 &cmd->body.dest.sid, NULL);
}

static int vmw_cmd_blt_surf_screen_check(struct vmw_private *dev_priv,
                                         struct vmw_sw_context *sw_context,
                                         SVGA3dCmdHeader *header)
{
        struct vmw_sid_cmd {
                SVGA3dCmdHeader header;
                SVGA3dCmdBlitSurfaceToScreen body;
        } *cmd;

        cmd = container_of(header, struct vmw_sid_cmd, header);

        if (unlikely(!sw_context->kernel)) {
                DRM_ERROR("Kernel only SVGA3d command: %u.\n", cmd->header.id);
                return -EPERM;
        }

        return vmw_cmd_res_check(dev_priv, sw_context, vmw_res_surface,
                                 user_surface_converter,
                                 &cmd->body.srcImage.sid, NULL);
}

static int vmw_cmd_present_check(struct vmw_private *dev_priv,
                                 struct vmw_sw_context *sw_context,
                                 SVGA3dCmdHeader *header)
{
        struct vmw_sid_cmd {
                SVGA3dCmdHeader header;
                SVGA3dCmdPresent body;
        } *cmd;


        cmd = container_of(header, struct vmw_sid_cmd, header);

        if (unlikely(!sw_context->kernel)) {
                DRM_ERROR("Kernel only SVGA3d command: %u.\n", cmd->header.id);
                return -EPERM;
        }

        return vmw_cmd_res_check(dev_priv, sw_context, vmw_res_surface,
                                 user_surface_converter, &cmd->body.sid,
                                 NULL);
}

/**
 * vmw_query_bo_switch_prepare - Prepare to switch pinned buffer for queries.
 *
 * @dev_priv: The device private structure.
 * @new_query_bo: The new buffer holding query results.
 * @sw_context: The software context used for this command submission.
 *
 * This function checks whether @new_query_bo is suitable for holding
 * query results, and if another buffer currently is pinned for query
 * results. If so, the function prepares the state of @sw_context for
 * switching pinned buffers after successful submission of the current
 * command batch.
 */
static int vmw_query_bo_switch_prepare(struct vmw_private *dev_priv,
                                       struct ttm_buffer_object *new_query_bo,
                                       struct vmw_sw_context *sw_context)
{
        struct vmw_res_cache_entry *ctx_entry =
                &sw_context->res_cache[vmw_res_context];
        int ret;

        BUG_ON(!ctx_entry->valid);
        sw_context->last_query_ctx = ctx_entry->res;

        if (unlikely(new_query_bo != sw_context->cur_query_bo)) {

                if (unlikely(new_query_bo->num_pages > 4)) {
                        DRM_ERROR("Query buffer too large.\n");
                        return -EINVAL;
                }

                if (unlikely(sw_context->cur_query_bo != NULL)) {
                        sw_context->needs_post_query_barrier = true;
                        ret = vmw_bo_to_validate_list(sw_context,
                                                      sw_context->cur_query_bo,
                                                      NULL);
                        if (unlikely(ret != 0))
                                return ret;
                }
                sw_context->cur_query_bo = new_query_bo;

                ret = vmw_bo_to_validate_list(sw_context,
                                              dev_priv->dummy_query_bo,
                                              NULL);
                if (unlikely(ret != 0))
                        return ret;

        }

        return 0;
}


/**
 * vmw_query_bo_switch_commit - Finalize switching pinned query buffer
 *
 * @dev_priv: The device private structure.
 * @sw_context: The software context used for this command submission batch.
 *
 * This function will check if we're switching query buffers, and will then,
 * issue a dummy occlusion query wait used as a query barrier. When the fence
 * object following that query wait has signaled, we are sure that all
 * preceding queries have finished, and the old query buffer can be unpinned.
 * However, since both the new query buffer and the old one are fenced with
 * that fence, we can do an asynchronus unpin now, and be sure that the
 * old query buffer won't be moved until the fence has signaled.
 *
 * As mentioned above, both the new - and old query buffers need to be fenced
 * using a sequence emitted *after* calling this function.
 */
static void vmw_query_bo_switch_commit(struct vmw_private *dev_priv,
                                     struct vmw_sw_context *sw_context)
{
        /*
         * The validate list should still hold references to all
         * contexts here.
         */

        if (sw_context->needs_post_query_barrier) {
                struct vmw_res_cache_entry *ctx_entry =
                        &sw_context->res_cache[vmw_res_context];
                struct vmw_resource *ctx;
                int ret;

                BUG_ON(!ctx_entry->valid);
                ctx = ctx_entry->res;

                ret = vmw_fifo_emit_dummy_query(dev_priv, ctx->id);

                if (unlikely(ret != 0))
                        DRM_ERROR("Out of fifo space for dummy query.\n");
        }

        if (dev_priv->pinned_bo != sw_context->cur_query_bo) {
                if (dev_priv->pinned_bo) {
                        vmw_bo_pin(dev_priv->pinned_bo, false);
                        ttm_bo_unref(&dev_priv->pinned_bo);
                }

                if (!sw_context->needs_post_query_barrier) {
                        vmw_bo_pin(sw_context->cur_query_bo, true);

                        /*
                         * We pin also the dummy_query_bo buffer so that we
                         * don't need to validate it when emitting
                         * dummy queries in context destroy paths.
                         */

                        vmw_bo_pin(dev_priv->dummy_query_bo, true);
                        dev_priv->dummy_query_bo_pinned = true;

                        BUG_ON(sw_context->last_query_ctx == NULL);
                        dev_priv->query_cid = sw_context->last_query_ctx->id;
                        dev_priv->query_cid_valid = true;
                        dev_priv->pinned_bo =
                                ttm_bo_reference(sw_context->cur_query_bo);
                }
        }
}

/**
 * vmw_translate_guest_pointer - Prepare to translate a user-space buffer
 * handle to a valid SVGAGuestPtr
 *
 * @dev_priv: Pointer to a device private structure.
 * @sw_context: The software context used for this command batch validation.
 * @ptr: Pointer to the user-space handle to be translated.
 * @vmw_bo_p: Points to a location that, on successful return will carry
 * a reference-counted pointer to the DMA buffer identified by the
 * user-space handle in @id.
 *
 * This function saves information needed to translate a user-space buffer
 * handle to a valid SVGAGuestPtr. The translation does not take place
 * immediately, but during a call to vmw_apply_relocations().
 * This function builds a relocation list and a list of buffers to validate.
 * The former needs to be freed using either vmw_apply_relocations() or
 * vmw_free_relocations(). The latter needs to be freed using
 * vmw_clear_validations.
 */
static int vmw_translate_guest_ptr(struct vmw_private *dev_priv,
                                   struct vmw_sw_context *sw_context,
                                   SVGAGuestPtr *ptr,
                                   struct vmw_dma_buffer **vmw_bo_p)
{
        struct vmw_dma_buffer *vmw_bo = NULL;
        struct ttm_buffer_object *bo;
        uint32_t handle = ptr->gmrId;
        struct vmw_relocation *reloc;
        int ret;

        ret = vmw_user_dmabuf_lookup(sw_context->tfile, handle, &vmw_bo);
        if (unlikely(ret != 0)) {
                DRM_ERROR("Could not find or use GMR region.\n");
                return -EINVAL;
        }
        bo = &vmw_bo->base;

        if (unlikely(sw_context->cur_reloc >= VMWGFX_MAX_RELOCATIONS)) {
                DRM_ERROR("Max number relocations per submission"
                          " exceeded\n");
                ret = -EINVAL;
                goto out_no_reloc;
        }

        reloc = &sw_context->relocs[sw_context->cur_reloc++];
        reloc->location = ptr;

        ret = vmw_bo_to_validate_list(sw_context, bo, &reloc->index);
        if (unlikely(ret != 0))
                goto out_no_reloc;

        *vmw_bo_p = vmw_bo;
        return 0;

out_no_reloc:
        vmw_dmabuf_unreference(&vmw_bo);
        vmw_bo_p = NULL;
        return ret;
}

/**
 * vmw_cmd_begin_query - validate a  SVGA_3D_CMD_BEGIN_QUERY command.
 *
 * @dev_priv: Pointer to a device private struct.
 * @sw_context: The software context used for this command submission.
 * @header: Pointer to the command header in the command stream.
 */
static int vmw_cmd_begin_query(struct vmw_private *dev_priv,
                               struct vmw_sw_context *sw_context,
                               SVGA3dCmdHeader *header)
{
        struct vmw_begin_query_cmd {
                SVGA3dCmdHeader header;
                SVGA3dCmdBeginQuery q;
        } *cmd;

        cmd = container_of(header, struct vmw_begin_query_cmd,
                           header);

        return vmw_cmd_res_check(dev_priv, sw_context, vmw_res_context,
                                 user_context_converter, &cmd->q.cid,
                                 NULL);
}

/**
 * vmw_cmd_end_query - validate a  SVGA_3D_CMD_END_QUERY command.
 *
 * @dev_priv: Pointer to a device private struct.
 * @sw_context: The software context used for this command submission.
 * @header: Pointer to the command header in the command stream.
 */
static int vmw_cmd_end_query(struct vmw_private *dev_priv,
                             struct vmw_sw_context *sw_context,
                             SVGA3dCmdHeader *header)
{
        struct vmw_dma_buffer *vmw_bo;
        struct vmw_query_cmd {
                SVGA3dCmdHeader header;
                SVGA3dCmdEndQuery q;
        } *cmd;
        int ret;

        cmd = container_of(header, struct vmw_query_cmd, header);
        ret = vmw_cmd_cid_check(dev_priv, sw_context, header);
        if (unlikely(ret != 0))
                return ret;

        ret = vmw_translate_guest_ptr(dev_priv, sw_context,
                                      &cmd->q.guestResult,
                                      &vmw_bo);
        if (unlikely(ret != 0))
                return ret;

        ret = vmw_query_bo_switch_prepare(dev_priv, &vmw_bo->base, sw_context);

        vmw_dmabuf_unreference(&vmw_bo);
        return ret;
}

/*
 * vmw_cmd_wait_query - validate a  SVGA_3D_CMD_WAIT_QUERY command.
 *
 * @dev_priv: Pointer to a device private struct.
 * @sw_context: The software context used for this command submission.
 * @header: Pointer to the command header in the command stream.
 */
static int vmw_cmd_wait_query(struct vmw_private *dev_priv,
                              struct vmw_sw_context *sw_context,
                              SVGA3dCmdHeader *header)
{
        struct vmw_dma_buffer *vmw_bo;
        struct vmw_query_cmd {
                SVGA3dCmdHeader header;
                SVGA3dCmdWaitForQuery q;
        } *cmd;
        int ret;

        cmd = container_of(header, struct vmw_query_cmd, header);
        ret = vmw_cmd_cid_check(dev_priv, sw_context, header);
        if (unlikely(ret != 0))
                return ret;

        ret = vmw_translate_guest_ptr(dev_priv, sw_context,
                                      &cmd->q.guestResult,
                                      &vmw_bo);
        if (unlikely(ret != 0))
                return ret;

        vmw_dmabuf_unreference(&vmw_bo);
        return 0;
}

static int vmw_cmd_dma(struct vmw_private *dev_priv,
                       struct vmw_sw_context *sw_context,
                       SVGA3dCmdHeader *header)
{
        struct vmw_dma_buffer *vmw_bo = NULL;
        struct vmw_surface *srf = NULL;
        struct vmw_dma_cmd {
                SVGA3dCmdHeader header;
                SVGA3dCmdSurfaceDMA dma;
        } *cmd;
        int ret;

        cmd = container_of(header, struct vmw_dma_cmd, header);
        ret = vmw_translate_guest_ptr(dev_priv, sw_context,
                                      &cmd->dma.guest.ptr,
                                      &vmw_bo);
        if (unlikely(ret != 0))
                return ret;

        ret = vmw_cmd_res_check(dev_priv, sw_context, vmw_res_surface,
                                user_surface_converter, &cmd->dma.host.sid,
                                NULL);
        if (unlikely(ret != 0)) {
                if (unlikely(ret != -ERESTARTSYS))
                        DRM_ERROR("could not find surface for DMA.\n");
                goto out_no_surface;
        }

        srf = vmw_res_to_srf(sw_context->res_cache[vmw_res_surface].res);

        vmw_kms_cursor_snoop(srf, sw_context->tfile, &vmw_bo->base, header);

out_no_surface:
        vmw_dmabuf_unreference(&vmw_bo);
        return ret;
}

static int vmw_cmd_draw(struct vmw_private *dev_priv,
                        struct vmw_sw_context *sw_context,
                        SVGA3dCmdHeader *header)
{
        struct vmw_draw_cmd {
                SVGA3dCmdHeader header;
                SVGA3dCmdDrawPrimitives body;
        } *cmd;
        SVGA3dVertexDecl *decl = (SVGA3dVertexDecl *)(
                (unsigned long)header + sizeof(*cmd));
        SVGA3dPrimitiveRange *range;
        uint32_t i;
        uint32_t maxnum;
        int ret;

        ret = vmw_cmd_cid_check(dev_priv, sw_context, header);
        if (unlikely(ret != 0))
                return ret;

        cmd = container_of(header, struct vmw_draw_cmd, header);
        maxnum = (header->size - sizeof(cmd->body)) / sizeof(*decl);

        if (unlikely(cmd->body.numVertexDecls > maxnum)) {
                DRM_ERROR("Illegal number of vertex declarations.\n");
                return -EINVAL;
        }

        for (i = 0; i < cmd->body.numVertexDecls; ++i, ++decl) {
                ret = vmw_cmd_res_check(dev_priv, sw_context, vmw_res_surface,
                                        user_surface_converter,
                                        &decl->array.surfaceId, NULL);
                if (unlikely(ret != 0))
                        return ret;
        }

        maxnum = (header->size - sizeof(cmd->body) -
                  cmd->body.numVertexDecls * sizeof(*decl)) / sizeof(*range);
        if (unlikely(cmd->body.numRanges > maxnum)) {
                DRM_ERROR("Illegal number of index ranges.\n");
                return -EINVAL;
        }

        range = (SVGA3dPrimitiveRange *) decl;
        for (i = 0; i < cmd->body.numRanges; ++i, ++range) {
                ret = vmw_cmd_res_check(dev_priv, sw_context, vmw_res_surface,
                                        user_surface_converter,
                                        &range->indexArray.surfaceId, NULL);
                if (unlikely(ret != 0))
                        return ret;
        }
        return 0;
}


static int vmw_cmd_tex_state(struct vmw_private *dev_priv,
                             struct vmw_sw_context *sw_context,
                             SVGA3dCmdHeader *header)
{
        struct vmw_tex_state_cmd {
                SVGA3dCmdHeader header;
                SVGA3dCmdSetTextureState state;
        };

        SVGA3dTextureState *last_state = (SVGA3dTextureState *)
          ((unsigned long) header + header->size + sizeof(header));
        SVGA3dTextureState *cur_state = (SVGA3dTextureState *)
                ((unsigned long) header + sizeof(struct vmw_tex_state_cmd));
        int ret;

        ret = vmw_cmd_cid_check(dev_priv, sw_context, header);
        if (unlikely(ret != 0))
                return ret;

        for (; cur_state < last_state; ++cur_state) {
                if (likely(cur_state->name != SVGA3D_TS_BIND_TEXTURE))
                        continue;

                ret = vmw_cmd_res_check(dev_priv, sw_context, vmw_res_surface,
                                        user_surface_converter,
                                        &cur_state->value, NULL);
                if (unlikely(ret != 0))
                        return ret;
        }

        return 0;
}

static int vmw_cmd_check_define_gmrfb(struct vmw_private *dev_priv,
                                      struct vmw_sw_context *sw_context,
                                      void *buf)
{
        struct vmw_dma_buffer *vmw_bo;
        int ret;

        struct {
                uint32_t header;
                SVGAFifoCmdDefineGMRFB body;
        } *cmd = buf;

        ret = vmw_translate_guest_ptr(dev_priv, sw_context,
                                      &cmd->body.ptr,
                                      &vmw_bo);
        if (unlikely(ret != 0))
                return ret;

        vmw_dmabuf_unreference(&vmw_bo);

        return ret;
}

/**
 * vmw_cmd_set_shader - Validate an SVGA_3D_CMD_SET_SHADER
 * command
 *
 * @dev_priv: Pointer to a device private struct.
 * @sw_context: The software context being used for this batch.
 * @header: Pointer to the command header in the command stream.
 */
static int vmw_cmd_set_shader(struct vmw_private *dev_priv,
                              struct vmw_sw_context *sw_context,
                              SVGA3dCmdHeader *header)
{
        struct vmw_set_shader_cmd {
                SVGA3dCmdHeader header;
                SVGA3dCmdSetShader body;
        } *cmd;
        int ret;

        cmd = container_of(header, struct vmw_set_shader_cmd,
                           header);

        ret = vmw_cmd_cid_check(dev_priv, sw_context, header);
        if (unlikely(ret != 0))
                return ret;

        return 0;
}

static int vmw_cmd_check_not_3d(struct vmw_private *dev_priv,
                                struct vmw_sw_context *sw_context,
                                void *buf, uint32_t *size)
{
        uint32_t size_remaining = *size;
        uint32_t cmd_id;

        cmd_id = le32_to_cpu(((uint32_t *)buf)[0]);
        switch (cmd_id) {
        case SVGA_CMD_UPDATE:
                *size = sizeof(uint32_t) + sizeof(SVGAFifoCmdUpdate);
                break;
        case SVGA_CMD_DEFINE_GMRFB:
                *size = sizeof(uint32_t) + sizeof(SVGAFifoCmdDefineGMRFB);
                break;
        case SVGA_CMD_BLIT_GMRFB_TO_SCREEN:
                *size = sizeof(uint32_t) + sizeof(SVGAFifoCmdBlitGMRFBToScreen);
                break;
        case SVGA_CMD_BLIT_SCREEN_TO_GMRFB:
                *size = sizeof(uint32_t) + sizeof(SVGAFifoCmdBlitGMRFBToScreen);
                break;
        default:
                DRM_ERROR("Unsupported SVGA command: %u.\n", cmd_id);
                return -EINVAL;
        }

        if (*size > size_remaining) {
                DRM_ERROR("Invalid SVGA command (size mismatch):"
                          " %u.\n", cmd_id);
                return -EINVAL;
        }

        if (unlikely(!sw_context->kernel)) {
                DRM_ERROR("Kernel only SVGA command: %u.\n", cmd_id);
                return -EPERM;
        }

        if (cmd_id == SVGA_CMD_DEFINE_GMRFB)
                return vmw_cmd_check_define_gmrfb(dev_priv, sw_context, buf);

        return 0;
}

typedef int (*vmw_cmd_func) (struct vmw_private *,
                             struct vmw_sw_context *,
                             SVGA3dCmdHeader *);

#define VMW_CMD_DEF(cmd, func) \
        [cmd - SVGA_3D_CMD_BASE] = func

static vmw_cmd_func vmw_cmd_funcs[SVGA_3D_CMD_MAX] = {
        VMW_CMD_DEF(SVGA_3D_CMD_SURFACE_DEFINE, &vmw_cmd_invalid),
        VMW_CMD_DEF(SVGA_3D_CMD_SURFACE_DESTROY, &vmw_cmd_invalid),
        VMW_CMD_DEF(SVGA_3D_CMD_SURFACE_COPY, &vmw_cmd_surface_copy_check),
        VMW_CMD_DEF(SVGA_3D_CMD_SURFACE_STRETCHBLT, &vmw_cmd_stretch_blt_check),
        VMW_CMD_DEF(SVGA_3D_CMD_SURFACE_DMA, &vmw_cmd_dma),
        VMW_CMD_DEF(SVGA_3D_CMD_CONTEXT_DEFINE, &vmw_cmd_invalid),
        VMW_CMD_DEF(SVGA_3D_CMD_CONTEXT_DESTROY, &vmw_cmd_invalid),
        VMW_CMD_DEF(SVGA_3D_CMD_SETTRANSFORM, &vmw_cmd_cid_check),
        VMW_CMD_DEF(SVGA_3D_CMD_SETZRANGE, &vmw_cmd_cid_check),
        VMW_CMD_DEF(SVGA_3D_CMD_SETRENDERSTATE, &vmw_cmd_cid_check),
        VMW_CMD_DEF(SVGA_3D_CMD_SETRENDERTARGET,
                    &vmw_cmd_set_render_target_check),
        VMW_CMD_DEF(SVGA_3D_CMD_SETTEXTURESTATE, &vmw_cmd_tex_state),
        VMW_CMD_DEF(SVGA_3D_CMD_SETMATERIAL, &vmw_cmd_cid_check),
        VMW_CMD_DEF(SVGA_3D_CMD_SETLIGHTDATA, &vmw_cmd_cid_check),
        VMW_CMD_DEF(SVGA_3D_CMD_SETLIGHTENABLED, &vmw_cmd_cid_check),
        VMW_CMD_DEF(SVGA_3D_CMD_SETVIEWPORT, &vmw_cmd_cid_check),
        VMW_CMD_DEF(SVGA_3D_CMD_SETCLIPPLANE, &vmw_cmd_cid_check),
        VMW_CMD_DEF(SVGA_3D_CMD_CLEAR, &vmw_cmd_cid_check),
        VMW_CMD_DEF(SVGA_3D_CMD_PRESENT, &vmw_cmd_present_check),
        VMW_CMD_DEF(SVGA_3D_CMD_SHADER_DEFINE, &vmw_cmd_cid_check),
        VMW_CMD_DEF(SVGA_3D_CMD_SHADER_DESTROY, &vmw_cmd_cid_check),
        VMW_CMD_DEF(SVGA_3D_CMD_SET_SHADER, &vmw_cmd_set_shader),
        VMW_CMD_DEF(SVGA_3D_CMD_SET_SHADER_CONST, &vmw_cmd_cid_check),
        VMW_CMD_DEF(SVGA_3D_CMD_DRAW_PRIMITIVES, &vmw_cmd_draw),
        VMW_CMD_DEF(SVGA_3D_CMD_SETSCISSORRECT, &vmw_cmd_cid_check),
        VMW_CMD_DEF(SVGA_3D_CMD_BEGIN_QUERY, &vmw_cmd_begin_query),
        VMW_CMD_DEF(SVGA_3D_CMD_END_QUERY, &vmw_cmd_end_query),
        VMW_CMD_DEF(SVGA_3D_CMD_WAIT_FOR_QUERY, &vmw_cmd_wait_query),
        VMW_CMD_DEF(SVGA_3D_CMD_PRESENT_READBACK, &vmw_cmd_ok),
        VMW_CMD_DEF(SVGA_3D_CMD_BLIT_SURFACE_TO_SCREEN,
                    &vmw_cmd_blt_surf_screen_check),
        VMW_CMD_DEF(SVGA_3D_CMD_SURFACE_DEFINE_V2, &vmw_cmd_invalid),
        VMW_CMD_DEF(SVGA_3D_CMD_GENERATE_MIPMAPS, &vmw_cmd_invalid),
        VMW_CMD_DEF(SVGA_3D_CMD_ACTIVATE_SURFACE, &vmw_cmd_invalid),
        VMW_CMD_DEF(SVGA_3D_CMD_DEACTIVATE_SURFACE, &vmw_cmd_invalid),
};

static int vmw_cmd_check(struct vmw_private *dev_priv,
                         struct vmw_sw_context *sw_context,
                         void *buf, uint32_t *size)
{
        uint32_t cmd_id;
        uint32_t size_remaining = *size;
        SVGA3dCmdHeader *header = (SVGA3dCmdHeader *) buf;
        int ret;

        cmd_id = le32_to_cpu(((uint32_t *)buf)[0]);
        /* Handle any none 3D commands */
        if (unlikely(cmd_id < SVGA_CMD_MAX))
                return vmw_cmd_check_not_3d(dev_priv, sw_context, buf, size);


        cmd_id = le32_to_cpu(header->id);
        *size = le32_to_cpu(header->size) + sizeof(SVGA3dCmdHeader);

        cmd_id -= SVGA_3D_CMD_BASE;
        if (unlikely(*size > size_remaining))
                goto out_err;

        if (unlikely(cmd_id >= SVGA_3D_CMD_MAX - SVGA_3D_CMD_BASE))
                goto out_err;

        ret = vmw_cmd_funcs[cmd_id](dev_priv, sw_context, header);
        if (unlikely(ret != 0))
                goto out_err;

        return 0;
out_err:
        DRM_ERROR("Illegal / Invalid SVGA3D command: %d\n",
                  cmd_id + SVGA_3D_CMD_BASE);
        return -EINVAL;
}

static int vmw_cmd_check_all(struct vmw_private *dev_priv,
                             struct vmw_sw_context *sw_context,
                             void *buf,
                             uint32_t size)
{
        int32_t cur_size = size;
        int ret;

        sw_context->buf_start = buf;

        while (cur_size > 0) {
                size = cur_size;
                ret = vmw_cmd_check(dev_priv, sw_context, buf, &size);
                if (unlikely(ret != 0))
                        return ret;
                buf = (void *)((unsigned long) buf + size);
                cur_size -= size;
        }

        if (unlikely(cur_size != 0)) {
                DRM_ERROR("Command verifier out of sync.\n");
                return -EINVAL;
        }

        return 0;
}

static void vmw_free_relocations(struct vmw_sw_context *sw_context)
{
        sw_context->cur_reloc = 0;
}

static void vmw_apply_relocations(struct vmw_sw_context *sw_context)
{
        uint32_t i;
        struct vmw_relocation *reloc;
        struct ttm_validate_buffer *validate;
        struct ttm_buffer_object *bo;

        for (i = 0; i < sw_context->cur_reloc; ++i) {
                reloc = &sw_context->relocs[i];
                validate = &sw_context->val_bufs[reloc->index].base;
                bo = validate->bo;
                switch (bo->mem.mem_type) {
                case TTM_PL_VRAM:
                        reloc->location->offset += bo->offset;
                        reloc->location->gmrId = SVGA_GMR_FRAMEBUFFER;
                        break;
                case VMW_PL_GMR:
                        reloc->location->gmrId = bo->mem.start;
                        break;
                default:
                        BUG();
                }
        }
        vmw_free_relocations(sw_context);
}

/**
 * vmw_resource_list_unrefererence - Free up a resource list and unreference
 * all resources referenced by it.
 *
 * @list: The resource list.
 */
static void vmw_resource_list_unreference(struct list_head *list)
{
        struct vmw_resource_val_node *val, *val_next;

        /*
         * Drop references to resources held during command submission.
         */

        list_for_each_entry_safe(val, val_next, list, head) {
                list_del_init(&val->head);
                vmw_resource_unreference(&val->res);
                kfree(val);
        }
}

static void vmw_clear_validations(struct vmw_sw_context *sw_context)
{
        struct vmw_validate_buffer *entry, *next;
        struct vmw_resource_val_node *val;

        /*
         * Drop references to DMA buffers held during command submission.
         */
        list_for_each_entry_safe(entry, next, &sw_context->validate_nodes,
                                 base.head) {
                list_del(&entry->base.head);
                ttm_bo_unref(&entry->base.bo);
                (void) drm_ht_remove_item(&sw_context->res_ht, &entry->hash);
                sw_context->cur_val_buf--;
        }
        BUG_ON(sw_context->cur_val_buf != 0);

        list_for_each_entry(val, &sw_context->resource_list, head)
                (void) drm_ht_remove_item(&sw_context->res_ht, &val->hash);
}

static int vmw_validate_single_buffer(struct vmw_private *dev_priv,
                                      struct ttm_buffer_object *bo)
{
        int ret;


        /*
         * Don't validate pinned buffers.
         */

        if (bo == dev_priv->pinned_bo ||
            (bo == dev_priv->dummy_query_bo &&
             dev_priv->dummy_query_bo_pinned))
                return 0;

        /**
         * Put BO in VRAM if there is space, otherwise as a GMR.
         * If there is no space in VRAM and GMR ids are all used up,
         * start evicting GMRs to make room. If the DMA buffer can't be
         * used as a GMR, this will return -ENOMEM.
         */

        ret = ttm_bo_validate(bo, &vmw_vram_gmr_placement, true, false);
        if (likely(ret == 0 || ret == -ERESTARTSYS))
                return ret;

        /**
         * If that failed, try VRAM again, this time evicting
         * previous contents.
         */

        DRM_INFO("Falling through to VRAM.\n");
        ret = ttm_bo_validate(bo, &vmw_vram_placement, true, false);
        return ret;
}


static int vmw_validate_buffers(struct vmw_private *dev_priv,
                                struct vmw_sw_context *sw_context)
{
        struct vmw_validate_buffer *entry;
        int ret;

        list_for_each_entry(entry, &sw_context->validate_nodes, base.head) {
                ret = vmw_validate_single_buffer(dev_priv, entry->base.bo);
                if (unlikely(ret != 0))
                        return ret;
        }
        return 0;
}

static int vmw_resize_cmd_bounce(struct vmw_sw_context *sw_context,
                                 uint32_t size)
{
        if (likely(sw_context->cmd_bounce_size >= size))
                return 0;

        if (sw_context->cmd_bounce_size == 0)
                sw_context->cmd_bounce_size = VMWGFX_CMD_BOUNCE_INIT_SIZE;

        while (sw_context->cmd_bounce_size < size) {
                sw_context->cmd_bounce_size =
                        PAGE_ALIGN(sw_context->cmd_bounce_size +
                                   (sw_context->cmd_bounce_size >> 1));
        }

        if (sw_context->cmd_bounce != NULL)
                vfree(sw_context->cmd_bounce);

        sw_context->cmd_bounce = vmalloc(sw_context->cmd_bounce_size);

        if (sw_context->cmd_bounce == NULL) {
                DRM_ERROR("Failed to allocate command bounce buffer.\n");
                sw_context->cmd_bounce_size = 0;
                return -ENOMEM;
        }

        return 0;
}

/**
 * vmw_execbuf_fence_commands - create and submit a command stream fence
 *
 * Creates a fence object and submits a command stream marker.
 * If this fails for some reason, We sync the fifo and return NULL.
 * It is then safe to fence buffers with a NULL pointer.
 *
 * If @p_handle is not NULL @file_priv must also not be NULL. Creates
 * a userspace handle if @p_handle is not NULL, otherwise not.
 */

int vmw_execbuf_fence_commands(struct drm_file *file_priv,
                               struct vmw_private *dev_priv,
                               struct vmw_fence_obj **p_fence,
                               uint32_t *p_handle)
{
        uint32_t sequence;
        int ret;
        bool synced = false;

        /* p_handle implies file_priv. */
        BUG_ON(p_handle != NULL && file_priv == NULL);

        ret = vmw_fifo_send_fence(dev_priv, &sequence);
        if (unlikely(ret != 0)) {
                DRM_ERROR("Fence submission error. Syncing.\n");
                synced = true;
        }

        if (p_handle != NULL)
                ret = vmw_user_fence_create(file_priv, dev_priv->fman,
                                            sequence,
                                            DRM_VMW_FENCE_FLAG_EXEC,
                                            p_fence, p_handle);
        else
                ret = vmw_fence_create(dev_priv->fman, sequence,
                                       DRM_VMW_FENCE_FLAG_EXEC,
                                       p_fence);

        if (unlikely(ret != 0 && !synced)) {
                (void) vmw_fallback_wait(dev_priv, false, false,
                                         sequence, false,
                                         VMW_FENCE_WAIT_TIMEOUT);
                *p_fence = NULL;
        }

        return 0;
}

/**
 * vmw_execbuf_copy_fence_user - copy fence object information to
 * user-space.
 *
 * @dev_priv: Pointer to a vmw_private struct.
 * @vmw_fp: Pointer to the struct vmw_fpriv representing the calling file.
 * @ret: Return value from fence object creation.
 * @user_fence_rep: User space address of a struct drm_vmw_fence_rep to
 * which the information should be copied.
 * @fence: Pointer to the fenc object.
 * @fence_handle: User-space fence handle.
 *
 * This function copies fence information to user-space. If copying fails,
 * The user-space struct drm_vmw_fence_rep::error member is hopefully
 * left untouched, and if it's preloaded with an -EFAULT by user-space,
 * the error will hopefully be detected.
 * Also if copying fails, user-space will be unable to signal the fence
 * object so we wait for it immediately, and then unreference the
 * user-space reference.
 */
void
vmw_execbuf_copy_fence_user(struct vmw_private *dev_priv,
                            struct vmw_fpriv *vmw_fp,
                            int ret,
                            struct drm_vmw_fence_rep __user *user_fence_rep,
                            struct vmw_fence_obj *fence,
                            uint32_t fence_handle)
{
        struct drm_vmw_fence_rep fence_rep;

        if (user_fence_rep == NULL)
                return;

        memset(&fence_rep, 0, sizeof(fence_rep));

        fence_rep.error = ret;
        if (ret == 0) {
                BUG_ON(fence == NULL);

                fence_rep.handle = fence_handle;
                fence_rep.seqno = fence->seqno;
                vmw_update_seqno(dev_priv, &dev_priv->fifo);
                fence_rep.passed_seqno = dev_priv->last_read_seqno;
        }

        /*
         * copy_to_user errors will be detected by user space not
         * seeing fence_rep::error filled in. Typically
         * user-space would have pre-set that member to -EFAULT.
         */
        ret = copy_to_user(user_fence_rep, &fence_rep,
                           sizeof(fence_rep));

        /*
         * User-space lost the fence object. We need to sync
         * and unreference the handle.
         */
        if (unlikely(ret != 0) && (fence_rep.error == 0)) {
                ttm_ref_object_base_unref(vmw_fp->tfile,
                                          fence_handle, TTM_REF_USAGE);
                DRM_ERROR("Fence copy error. Syncing.\n");
                (void) vmw_fence_obj_wait(fence, fence->signal_mask,
                                          false, false,
                                          VMW_FENCE_WAIT_TIMEOUT);
        }
}

int vmw_execbuf_process(struct drm_file *file_priv,
                        struct vmw_private *dev_priv,
                        void __user *user_commands,
                        void *kernel_commands,
                        uint32_t command_size,
                        uint64_t throttle_us,
                        struct drm_vmw_fence_rep __user *user_fence_rep,
                        struct vmw_fence_obj **out_fence)
{
        struct vmw_sw_context *sw_context = &dev_priv->ctx;
        struct vmw_fence_obj *fence = NULL;
        struct vmw_resource *error_resource;
        struct list_head resource_list;
        struct ww_acquire_ctx ticket;
        uint32_t handle;
        void *cmd;
        int ret;

        ret = mutex_lock_interruptible(&dev_priv->cmdbuf_mutex);
        if (unlikely(ret != 0))
                return -ERESTARTSYS;

        if (kernel_commands == NULL) {
                sw_context->kernel = false;

                ret = vmw_resize_cmd_bounce(sw_context, command_size);
                if (unlikely(ret != 0))
                        goto out_unlock;


                ret = copy_from_user(sw_context->cmd_bounce,
                                     user_commands, command_size);

                if (unlikely(ret != 0)) {
                        ret = -EFAULT;
                        DRM_ERROR("Failed copying commands.\n");
                        goto out_unlock;
                }
                kernel_commands = sw_context->cmd_bounce;
        } else
                sw_context->kernel = true;

        sw_context->tfile = vmw_fpriv(file_priv)->tfile;
        sw_context->cur_reloc = 0;
        sw_context->cur_val_buf = 0;
        sw_context->fence_flags = 0;
        INIT_LIST_HEAD(&sw_context->resource_list);
        sw_context->cur_query_bo = dev_priv->pinned_bo;
        sw_context->last_query_ctx = NULL;
        sw_context->needs_post_query_barrier = false;
        memset(sw_context->res_cache, 0, sizeof(sw_context->res_cache));
        INIT_LIST_HEAD(&sw_context->validate_nodes);
        INIT_LIST_HEAD(&sw_context->res_relocations);
        if (!sw_context->res_ht_initialized) {
                ret = drm_ht_create(&sw_context->res_ht, VMW_RES_HT_ORDER);
                if (unlikely(ret != 0))
                        goto out_unlock;
                sw_context->res_ht_initialized = true;
        }

        INIT_LIST_HEAD(&resource_list);
        ret = vmw_cmd_check_all(dev_priv, sw_context, kernel_commands,
                                command_size);
        if (unlikely(ret != 0))
                goto out_err;

        ret = vmw_resources_reserve(sw_context);
        if (unlikely(ret != 0))
                goto out_err;

        ret = ttm_eu_reserve_buffers(&ticket, &sw_context->validate_nodes);
        if (unlikely(ret != 0))
                goto out_err;

        ret = vmw_validate_buffers(dev_priv, sw_context);
        if (unlikely(ret != 0))
                goto out_err;

        ret = vmw_resources_validate(sw_context);
        if (unlikely(ret != 0))
                goto out_err;

        if (throttle_us) {
                ret = vmw_wait_lag(dev_priv, &dev_priv->fifo.marker_queue,
                                   throttle_us);

                if (unlikely(ret != 0))
                        goto out_err;
        }

        cmd = vmw_fifo_reserve(dev_priv, command_size);
        if (unlikely(cmd == NULL)) {
                DRM_ERROR("Failed reserving fifo space for commands.\n");
                ret = -ENOMEM;
                goto out_err;
        }

        vmw_apply_relocations(sw_context);
        memcpy(cmd, kernel_commands, command_size);

        vmw_resource_relocations_apply(cmd, &sw_context->res_relocations);
        vmw_resource_relocations_free(&sw_context->res_relocations);

        vmw_fifo_commit(dev_priv, command_size);

        vmw_query_bo_switch_commit(dev_priv, sw_context);
        ret = vmw_execbuf_fence_commands(file_priv, dev_priv,
                                         &fence,
                                         (user_fence_rep) ? &handle : NULL);
        /*
         * This error is harmless, because if fence submission fails,
         * vmw_fifo_send_fence will sync. The error will be propagated to
         * user-space in @fence_rep
         */

        if (ret != 0)
                DRM_ERROR("Fence submission error. Syncing.\n");

        vmw_resource_list_unreserve(&sw_context->resource_list, false);
        ttm_eu_fence_buffer_objects(&ticket, &sw_context->validate_nodes,
                                    (void *) fence);

        if (unlikely(dev_priv->pinned_bo != NULL &&
                     !dev_priv->query_cid_valid))
                __vmw_execbuf_release_pinned_bo(dev_priv, fence);

        vmw_clear_validations(sw_context);
        vmw_execbuf_copy_fence_user(dev_priv, vmw_fpriv(file_priv), ret,
                                    user_fence_rep, fence, handle);

        /* Don't unreference when handing fence out */
        if (unlikely(out_fence != NULL)) {
                *out_fence = fence;
                fence = NULL;
        } else if (likely(fence != NULL)) {
                vmw_fence_obj_unreference(&fence);
        }

        list_splice_init(&sw_context->resource_list, &resource_list);
        mutex_unlock(&dev_priv->cmdbuf_mutex);

        /*
         * Unreference resources outside of the cmdbuf_mutex to
         * avoid deadlocks in resource destruction paths.
         */
        vmw_resource_list_unreference(&resource_list);

        return 0;

out_err:
        vmw_resource_relocations_free(&sw_context->res_relocations);
        vmw_free_relocations(sw_context);
        ttm_eu_backoff_reservation(&ticket, &sw_context->validate_nodes);
        vmw_resource_list_unreserve(&sw_context->resource_list, true);
        vmw_clear_validations(sw_context);
        if (unlikely(dev_priv->pinned_bo != NULL &&
                     !dev_priv->query_cid_valid))
                __vmw_execbuf_release_pinned_bo(dev_priv, NULL);
out_unlock:
        list_splice_init(&sw_context->resource_list, &resource_list);
        error_resource = sw_context->error_resource;
        sw_context->error_resource = NULL;
        mutex_unlock(&dev_priv->cmdbuf_mutex);

        /*
         * Unreference resources outside of the cmdbuf_mutex to
         * avoid deadlocks in resource destruction paths.
         */
        vmw_resource_list_unreference(&resource_list);
        if (unlikely(error_resource != NULL))
                vmw_resource_unreference(&error_resource);

        return ret;
}

/**
 * vmw_execbuf_unpin_panic - Idle the fifo and unpin the query buffer.
 *
 * @dev_priv: The device private structure.
 *
 * This function is called to idle the fifo and unpin the query buffer
 * if the normal way to do this hits an error, which should typically be
 * extremely rare.
 */
static void vmw_execbuf_unpin_panic(struct vmw_private *dev_priv)
{
        DRM_ERROR("Can't unpin query buffer. Trying to recover.\n");

        (void) vmw_fallback_wait(dev_priv, false, true, 0, false, 10*HZ);
        vmw_bo_pin(dev_priv->pinned_bo, false);
        vmw_bo_pin(dev_priv->dummy_query_bo, false);
        dev_priv->dummy_query_bo_pinned = false;
}


/**
 * __vmw_execbuf_release_pinned_bo - Flush queries and unpin the pinned
 * query bo.
 *
 * @dev_priv: The device private structure.
 * @fence: If non-NULL should point to a struct vmw_fence_obj issued
 * _after_ a query barrier that flushes all queries touching the current
 * buffer pointed to by @dev_priv->pinned_bo
 *
 * This function should be used to unpin the pinned query bo, or
 * as a query barrier when we need to make sure that all queries have
 * finished before the next fifo command. (For example on hardware
 * context destructions where the hardware may otherwise leak unfinished
 * queries).
 *
 * This function does not return any failure codes, but make attempts
 * to do safe unpinning in case of errors.
 *
 * The function will synchronize on the previous query barrier, and will
 * thus not finish until that barrier has executed.
 *
 * the @dev_priv->cmdbuf_mutex needs to be held by the current thread
 * before calling this function.
 */
void __vmw_execbuf_release_pinned_bo(struct vmw_private *dev_priv,
                                     struct vmw_fence_obj *fence)
{
        int ret = 0;
        struct list_head validate_list;
        struct ttm_validate_buffer pinned_val, query_val;
        struct vmw_fence_obj *lfence = NULL;
        struct ww_acquire_ctx ticket;

        if (dev_priv->pinned_bo == NULL)
                goto out_unlock;

        INIT_LIST_HEAD(&validate_list);

        pinned_val.bo = ttm_bo_reference(dev_priv->pinned_bo);
        list_add_tail(&pinned_val.head, &validate_list);

        query_val.bo = ttm_bo_reference(dev_priv->dummy_query_bo);
        list_add_tail(&query_val.head, &validate_list);

        do {
                ret = ttm_eu_reserve_buffers(&ticket, &validate_list);
        } while (ret == -ERESTARTSYS);

        if (unlikely(ret != 0)) {
                vmw_execbuf_unpin_panic(dev_priv);
                goto out_no_reserve;
        }

        if (dev_priv->query_cid_valid) {
                BUG_ON(fence != NULL);
                ret = vmw_fifo_emit_dummy_query(dev_priv, dev_priv->query_cid);
                if (unlikely(ret != 0)) {
                        vmw_execbuf_unpin_panic(dev_priv);
                        goto out_no_emit;
                }
                dev_priv->query_cid_valid = false;
        }

        vmw_bo_pin(dev_priv->pinned_bo, false);
        vmw_bo_pin(dev_priv->dummy_query_bo, false);
        dev_priv->dummy_query_bo_pinned = false;

        if (fence == NULL) {
                (void) vmw_execbuf_fence_commands(NULL, dev_priv, &lfence,
                                                  NULL);
                fence = lfence;
        }
        ttm_eu_fence_buffer_objects(&ticket, &validate_list, (void *) fence);
        if (lfence != NULL)
                vmw_fence_obj_unreference(&lfence);

        ttm_bo_unref(&query_val.bo);
        ttm_bo_unref(&pinned_val.bo);
        ttm_bo_unref(&dev_priv->pinned_bo);

out_unlock:
        return;

out_no_emit:
        ttm_eu_backoff_reservation(&ticket, &validate_list);
out_no_reserve:
        ttm_bo_unref(&query_val.bo);
        ttm_bo_unref(&pinned_val.bo);
        ttm_bo_unref(&dev_priv->pinned_bo);
}

/**
 * vmw_execbuf_release_pinned_bo - Flush queries and unpin the pinned
 * query bo.
 *
 * @dev_priv: The device private structure.
 *
 * This function should be used to unpin the pinned query bo, or
 * as a query barrier when we need to make sure that all queries have
 * finished before the next fifo command. (For example on hardware
 * context destructions where the hardware may otherwise leak unfinished
 * queries).
 *
 * This function does not return any failure codes, but make attempts
 * to do safe unpinning in case of errors.
 *
 * The function will synchronize on the previous query barrier, and will
 * thus not finish until that barrier has executed.
 */
void vmw_execbuf_release_pinned_bo(struct vmw_private *dev_priv)
{
        mutex_lock(&dev_priv->cmdbuf_mutex);
        if (dev_priv->query_cid_valid)
                __vmw_execbuf_release_pinned_bo(dev_priv, NULL);
        mutex_unlock(&dev_priv->cmdbuf_mutex);
}


int vmw_execbuf_ioctl(struct drm_device *dev, void *data,
                      struct drm_file *file_priv)
{
        struct vmw_private *dev_priv = vmw_priv(dev);
        struct drm_vmw_execbuf_arg *arg = (struct drm_vmw_execbuf_arg *)data;
        struct vmw_master *vmaster = vmw_master(file_priv->master);
        int ret;

        /*
         * This will allow us to extend the ioctl argument while
         * maintaining backwards compatibility:
         * We take different code paths depending on the value of
         * arg->version.
         */

        if (unlikely(arg->version != DRM_VMW_EXECBUF_VERSION)) {
                DRM_ERROR("Incorrect execbuf version.\n");
                DRM_ERROR("You're running outdated experimental "
                          "vmwgfx user-space drivers.");
                return -EINVAL;
        }

        ret = ttm_read_lock(&vmaster->lock, true);
        if (unlikely(ret != 0))
                return ret;

        ret = vmw_execbuf_process(file_priv, dev_priv,
                                  (void __user *)(unsigned long)arg->commands,
                                  NULL, arg->command_size, arg->throttle_us,
                                  (void __user *)(unsigned long)arg->fence_rep,
                                  NULL);

        if (unlikely(ret != 0))
                goto out_unlock;

        vmw_kms_cursor_post_execbuf(dev_priv);

out_unlock:
        ttm_read_unlock(&vmaster->lock);
        return ret;
}