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[linux/fpc-iii.git] / drivers / gpu / drm / vmwgfx / vmwgfx_shader.c

/**************************************************************************
 *
 * Copyright © 2009-2012 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_resource_priv.h"
#include "ttm/ttm_placement.h"

#define VMW_COMPAT_SHADER_HT_ORDER 12

struct vmw_shader {
        struct vmw_resource res;
        SVGA3dShaderType type;
        uint32_t size;
};

struct vmw_user_shader {
        struct ttm_base_object base;
        struct vmw_shader shader;
};

/**
 * enum vmw_compat_shader_state - Staging state for compat shaders
 */
enum vmw_compat_shader_state {
        VMW_COMPAT_COMMITED,
        VMW_COMPAT_ADD,
        VMW_COMPAT_DEL
};

/**
 * struct vmw_compat_shader - Metadata for compat shaders.
 *
 * @handle: The TTM handle of the guest backed shader.
 * @tfile: The struct ttm_object_file the guest backed shader is registered
 * with.
 * @hash: Hash item for lookup.
 * @head: List head for staging lists or the compat shader manager list.
 * @state: Staging state.
 *
 * The structure is protected by the cmdbuf lock.
 */
struct vmw_compat_shader {
        u32 handle;
        struct ttm_object_file *tfile;
        struct drm_hash_item hash;
        struct list_head head;
        enum vmw_compat_shader_state state;
};

/**
 * struct vmw_compat_shader_manager - Compat shader manager.
 *
 * @shaders: Hash table containing staged and commited compat shaders
 * @list: List of commited shaders.
 * @dev_priv: Pointer to a device private structure.
 *
 * @shaders and @list are protected by the cmdbuf mutex for now.
 */
struct vmw_compat_shader_manager {
        struct drm_open_hash shaders;
        struct list_head list;
        struct vmw_private *dev_priv;
};

static void vmw_user_shader_free(struct vmw_resource *res);
static struct vmw_resource *
vmw_user_shader_base_to_res(struct ttm_base_object *base);

static int vmw_gb_shader_create(struct vmw_resource *res);
static int vmw_gb_shader_bind(struct vmw_resource *res,
                               struct ttm_validate_buffer *val_buf);
static int vmw_gb_shader_unbind(struct vmw_resource *res,
                                 bool readback,
                                 struct ttm_validate_buffer *val_buf);
static int vmw_gb_shader_destroy(struct vmw_resource *res);

static uint64_t vmw_user_shader_size;

static const struct vmw_user_resource_conv user_shader_conv = {
        .object_type = VMW_RES_SHADER,
        .base_obj_to_res = vmw_user_shader_base_to_res,
        .res_free = vmw_user_shader_free
};

const struct vmw_user_resource_conv *user_shader_converter =
        &user_shader_conv;


static const struct vmw_res_func vmw_gb_shader_func = {
        .res_type = vmw_res_shader,
        .needs_backup = true,
        .may_evict = true,
        .type_name = "guest backed shaders",
        .backup_placement = &vmw_mob_placement,
        .create = vmw_gb_shader_create,
        .destroy = vmw_gb_shader_destroy,
        .bind = vmw_gb_shader_bind,
        .unbind = vmw_gb_shader_unbind
};

/**
 * Shader management:
 */

static inline struct vmw_shader *
vmw_res_to_shader(struct vmw_resource *res)
{
        return container_of(res, struct vmw_shader, res);
}

static void vmw_hw_shader_destroy(struct vmw_resource *res)
{
        (void) vmw_gb_shader_destroy(res);
}

static int vmw_gb_shader_init(struct vmw_private *dev_priv,
                              struct vmw_resource *res,
                              uint32_t size,
                              uint64_t offset,
                              SVGA3dShaderType type,
                              struct vmw_dma_buffer *byte_code,
                              void (*res_free) (struct vmw_resource *res))
{
        struct vmw_shader *shader = vmw_res_to_shader(res);
        int ret;

        ret = vmw_resource_init(dev_priv, res, true,
                                res_free, &vmw_gb_shader_func);


        if (unlikely(ret != 0)) {
                if (res_free)
                        res_free(res);
                else
                        kfree(res);
                return ret;
        }

        res->backup_size = size;
        if (byte_code) {
                res->backup = vmw_dmabuf_reference(byte_code);
                res->backup_offset = offset;
        }
        shader->size = size;
        shader->type = type;

        vmw_resource_activate(res, vmw_hw_shader_destroy);
        return 0;
}

static int vmw_gb_shader_create(struct vmw_resource *res)
{
        struct vmw_private *dev_priv = res->dev_priv;
        struct vmw_shader *shader = vmw_res_to_shader(res);
        int ret;
        struct {
                SVGA3dCmdHeader header;
                SVGA3dCmdDefineGBShader body;
        } *cmd;

        if (likely(res->id != -1))
                return 0;

        ret = vmw_resource_alloc_id(res);
        if (unlikely(ret != 0)) {
                DRM_ERROR("Failed to allocate a shader id.\n");
                goto out_no_id;
        }

        if (unlikely(res->id >= VMWGFX_NUM_GB_SHADER)) {
                ret = -EBUSY;
                goto out_no_fifo;
        }

        cmd = vmw_fifo_reserve(dev_priv, sizeof(*cmd));
        if (unlikely(cmd == NULL)) {
                DRM_ERROR("Failed reserving FIFO space for shader "
                          "creation.\n");
                ret = -ENOMEM;
                goto out_no_fifo;
        }

        cmd->header.id = SVGA_3D_CMD_DEFINE_GB_SHADER;
        cmd->header.size = sizeof(cmd->body);
        cmd->body.shid = res->id;
        cmd->body.type = shader->type;
        cmd->body.sizeInBytes = shader->size;
        vmw_fifo_commit(dev_priv, sizeof(*cmd));
        (void) vmw_3d_resource_inc(dev_priv, false);

        return 0;

out_no_fifo:
        vmw_resource_release_id(res);
out_no_id:
        return ret;
}

static int vmw_gb_shader_bind(struct vmw_resource *res,
                              struct ttm_validate_buffer *val_buf)
{
        struct vmw_private *dev_priv = res->dev_priv;
        struct {
                SVGA3dCmdHeader header;
                SVGA3dCmdBindGBShader body;
        } *cmd;
        struct ttm_buffer_object *bo = val_buf->bo;

        BUG_ON(bo->mem.mem_type != VMW_PL_MOB);

        cmd = vmw_fifo_reserve(dev_priv, sizeof(*cmd));
        if (unlikely(cmd == NULL)) {
                DRM_ERROR("Failed reserving FIFO space for shader "
                          "binding.\n");
                return -ENOMEM;
        }

        cmd->header.id = SVGA_3D_CMD_BIND_GB_SHADER;
        cmd->header.size = sizeof(cmd->body);
        cmd->body.shid = res->id;
        cmd->body.mobid = bo->mem.start;
        cmd->body.offsetInBytes = 0;
        res->backup_dirty = false;
        vmw_fifo_commit(dev_priv, sizeof(*cmd));

        return 0;
}

static int vmw_gb_shader_unbind(struct vmw_resource *res,
                                bool readback,
                                struct ttm_validate_buffer *val_buf)
{
        struct vmw_private *dev_priv = res->dev_priv;
        struct {
                SVGA3dCmdHeader header;
                SVGA3dCmdBindGBShader body;
        } *cmd;
        struct vmw_fence_obj *fence;

        BUG_ON(res->backup->base.mem.mem_type != VMW_PL_MOB);

        cmd = vmw_fifo_reserve(dev_priv, sizeof(*cmd));
        if (unlikely(cmd == NULL)) {
                DRM_ERROR("Failed reserving FIFO space for shader "
                          "unbinding.\n");
                return -ENOMEM;
        }

        cmd->header.id = SVGA_3D_CMD_BIND_GB_SHADER;
        cmd->header.size = sizeof(cmd->body);
        cmd->body.shid = res->id;
        cmd->body.mobid = SVGA3D_INVALID_ID;
        cmd->body.offsetInBytes = 0;
        vmw_fifo_commit(dev_priv, sizeof(*cmd));

        /*
         * Create a fence object and fence the backup buffer.
         */

        (void) vmw_execbuf_fence_commands(NULL, dev_priv,
                                          &fence, NULL);

        vmw_fence_single_bo(val_buf->bo, fence);

        if (likely(fence != NULL))
                vmw_fence_obj_unreference(&fence);

        return 0;
}

static int vmw_gb_shader_destroy(struct vmw_resource *res)
{
        struct vmw_private *dev_priv = res->dev_priv;
        struct {
                SVGA3dCmdHeader header;
                SVGA3dCmdDestroyGBShader body;
        } *cmd;

        if (likely(res->id == -1))
                return 0;

        mutex_lock(&dev_priv->binding_mutex);
        vmw_context_binding_res_list_scrub(&res->binding_head);

        cmd = vmw_fifo_reserve(dev_priv, sizeof(*cmd));
        if (unlikely(cmd == NULL)) {
                DRM_ERROR("Failed reserving FIFO space for shader "
                          "destruction.\n");
                mutex_unlock(&dev_priv->binding_mutex);
                return -ENOMEM;
        }

        cmd->header.id = SVGA_3D_CMD_DESTROY_GB_SHADER;
        cmd->header.size = sizeof(cmd->body);
        cmd->body.shid = res->id;
        vmw_fifo_commit(dev_priv, sizeof(*cmd));
        mutex_unlock(&dev_priv->binding_mutex);
        vmw_resource_release_id(res);
        vmw_3d_resource_dec(dev_priv, false);

        return 0;
}

/**
 * User-space shader management:
 */

static struct vmw_resource *
vmw_user_shader_base_to_res(struct ttm_base_object *base)
{
        return &(container_of(base, struct vmw_user_shader, base)->
                 shader.res);
}

static void vmw_user_shader_free(struct vmw_resource *res)
{
        struct vmw_user_shader *ushader =
                container_of(res, struct vmw_user_shader, shader.res);
        struct vmw_private *dev_priv = res->dev_priv;

        ttm_base_object_kfree(ushader, base);
        ttm_mem_global_free(vmw_mem_glob(dev_priv),
                            vmw_user_shader_size);
}

/**
 * This function is called when user space has no more references on the
 * base object. It releases the base-object's reference on the resource object.
 */

static void vmw_user_shader_base_release(struct ttm_base_object **p_base)
{
        struct ttm_base_object *base = *p_base;
        struct vmw_resource *res = vmw_user_shader_base_to_res(base);

        *p_base = NULL;
        vmw_resource_unreference(&res);
}

int vmw_shader_destroy_ioctl(struct drm_device *dev, void *data,
                              struct drm_file *file_priv)
{
        struct drm_vmw_shader_arg *arg = (struct drm_vmw_shader_arg *)data;
        struct ttm_object_file *tfile = vmw_fpriv(file_priv)->tfile;

        return ttm_ref_object_base_unref(tfile, arg->handle,
                                         TTM_REF_USAGE);
}

int vmw_shader_alloc(struct vmw_private *dev_priv,
                     struct vmw_dma_buffer *buffer,
                     size_t shader_size,
                     size_t offset,
                     SVGA3dShaderType shader_type,
                     struct ttm_object_file *tfile,
                     u32 *handle)
{
        struct vmw_user_shader *ushader;
        struct vmw_resource *res, *tmp;
        int ret;

        /*
         * Approximate idr memory usage with 128 bytes. It will be limited
         * by maximum number_of shaders anyway.
         */
        if (unlikely(vmw_user_shader_size == 0))
                vmw_user_shader_size =
                        ttm_round_pot(sizeof(struct vmw_user_shader)) + 128;

        ret = ttm_mem_global_alloc(vmw_mem_glob(dev_priv),
                                   vmw_user_shader_size,
                                   false, true);
        if (unlikely(ret != 0)) {
                if (ret != -ERESTARTSYS)
                        DRM_ERROR("Out of graphics memory for shader "
                                  "creation.\n");
                goto out;
        }

        ushader = kzalloc(sizeof(*ushader), GFP_KERNEL);
        if (unlikely(ushader == NULL)) {
                ttm_mem_global_free(vmw_mem_glob(dev_priv),
                                    vmw_user_shader_size);
                ret = -ENOMEM;
                goto out;
        }

        res = &ushader->shader.res;
        ushader->base.shareable = false;
        ushader->base.tfile = NULL;

        /*
         * From here on, the destructor takes over resource freeing.
         */

        ret = vmw_gb_shader_init(dev_priv, res, shader_size,
                                 offset, shader_type, buffer,
                                 vmw_user_shader_free);
        if (unlikely(ret != 0))
                goto out;

        tmp = vmw_resource_reference(res);
        ret = ttm_base_object_init(tfile, &ushader->base, false,
                                   VMW_RES_SHADER,
                                   &vmw_user_shader_base_release, NULL);

        if (unlikely(ret != 0)) {
                vmw_resource_unreference(&tmp);
                goto out_err;
        }

        if (handle)
                *handle = ushader->base.hash.key;
out_err:
        vmw_resource_unreference(&res);
out:
        return ret;
}


int vmw_shader_define_ioctl(struct drm_device *dev, void *data,
                             struct drm_file *file_priv)
{
        struct vmw_private *dev_priv = vmw_priv(dev);
        struct drm_vmw_shader_create_arg *arg =
                (struct drm_vmw_shader_create_arg *)data;
        struct ttm_object_file *tfile = vmw_fpriv(file_priv)->tfile;
        struct vmw_master *vmaster = vmw_master(file_priv->master);
        struct vmw_dma_buffer *buffer = NULL;
        SVGA3dShaderType shader_type;
        int ret;

        if (arg->buffer_handle != SVGA3D_INVALID_ID) {
                ret = vmw_user_dmabuf_lookup(tfile, arg->buffer_handle,
                                             &buffer);
                if (unlikely(ret != 0)) {
                        DRM_ERROR("Could not find buffer for shader "
                                  "creation.\n");
                        return ret;
                }

                if ((u64)buffer->base.num_pages * PAGE_SIZE <
                    (u64)arg->size + (u64)arg->offset) {
                        DRM_ERROR("Illegal buffer- or shader size.\n");
                        ret = -EINVAL;
                        goto out_bad_arg;
                }
        }

        switch (arg->shader_type) {
        case drm_vmw_shader_type_vs:
                shader_type = SVGA3D_SHADERTYPE_VS;
                break;
        case drm_vmw_shader_type_ps:
                shader_type = SVGA3D_SHADERTYPE_PS;
                break;
        case drm_vmw_shader_type_gs:
                shader_type = SVGA3D_SHADERTYPE_GS;
                break;
        default:
                DRM_ERROR("Illegal shader type.\n");
                ret = -EINVAL;
                goto out_bad_arg;
        }

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

        ret = vmw_shader_alloc(dev_priv, buffer, arg->size, arg->offset,
                               shader_type, tfile, &arg->shader_handle);

        ttm_read_unlock(&vmaster->lock);
out_bad_arg:
        vmw_dmabuf_unreference(&buffer);
        return ret;
}

/**
 * vmw_compat_shader_lookup - Look up a compat shader
 *
 * @man: Pointer to the compat shader manager.
 * @shader_type: The shader type, that combined with the user_key identifies
 * the shader.
 * @user_key: On entry, this should be a pointer to the user_key.
 * On successful exit, it will contain the guest-backed shader's TTM handle.
 *
 * Returns 0 on success. Non-zero on failure, in which case the value pointed
 * to by @user_key is unmodified.
 */
int vmw_compat_shader_lookup(struct vmw_compat_shader_manager *man,
                             SVGA3dShaderType shader_type,
                             u32 *user_key)
{
        struct drm_hash_item *hash;
        int ret;
        unsigned long key = *user_key | (shader_type << 24);

        ret = drm_ht_find_item(&man->shaders, key, &hash);
        if (unlikely(ret != 0))
                return ret;

        *user_key = drm_hash_entry(hash, struct vmw_compat_shader,
                                   hash)->handle;

        return 0;
}

/**
 * vmw_compat_shader_free - Free a compat shader.
 *
 * @man: Pointer to the compat shader manager.
 * @entry: Pointer to a struct vmw_compat_shader.
 *
 * Frees a struct vmw_compat_shder entry and drops its reference to the
 * guest backed shader.
 */
static void vmw_compat_shader_free(struct vmw_compat_shader_manager *man,
                                   struct vmw_compat_shader *entry)
{
        list_del(&entry->head);
        WARN_ON(drm_ht_remove_item(&man->shaders, &entry->hash));
        WARN_ON(ttm_ref_object_base_unref(entry->tfile, entry->handle,
                                          TTM_REF_USAGE));
        kfree(entry);
}

/**
 * vmw_compat_shaders_commit - Commit a list of compat shader actions.
 *
 * @man: Pointer to the compat shader manager.
 * @list: Caller's list of compat shader actions.
 *
 * This function commits a list of compat shader additions or removals.
 * It is typically called when the execbuf ioctl call triggering these
 * actions has commited the fifo contents to the device.
 */
void vmw_compat_shaders_commit(struct vmw_compat_shader_manager *man,
                               struct list_head *list)
{
        struct vmw_compat_shader *entry, *next;

        list_for_each_entry_safe(entry, next, list, head) {
                list_del(&entry->head);
                switch (entry->state) {
                case VMW_COMPAT_ADD:
                        entry->state = VMW_COMPAT_COMMITED;
                        list_add_tail(&entry->head, &man->list);
                        break;
                case VMW_COMPAT_DEL:
                        ttm_ref_object_base_unref(entry->tfile, entry->handle,
                                                  TTM_REF_USAGE);
                        kfree(entry);
                        break;
                default:
                        BUG();
                        break;
                }
        }
}

/**
 * vmw_compat_shaders_revert - Revert a list of compat shader actions
 *
 * @man: Pointer to the compat shader manager.
 * @list: Caller's list of compat shader actions.
 *
 * This function reverts a list of compat shader additions or removals.
 * It is typically called when the execbuf ioctl call triggering these
 * actions failed for some reason, and the command stream was never
 * submitted.
 */
void vmw_compat_shaders_revert(struct vmw_compat_shader_manager *man,
                               struct list_head *list)
{
        struct vmw_compat_shader *entry, *next;
        int ret;

        list_for_each_entry_safe(entry, next, list, head) {
                switch (entry->state) {
                case VMW_COMPAT_ADD:
                        vmw_compat_shader_free(man, entry);
                        break;
                case VMW_COMPAT_DEL:
                        ret = drm_ht_insert_item(&man->shaders, &entry->hash);
                        list_del(&entry->head);
                        list_add_tail(&entry->head, &man->list);
                        entry->state = VMW_COMPAT_COMMITED;
                        break;
                default:
                        BUG();
                        break;
                }
        }
}

/**
 * vmw_compat_shader_remove - Stage a compat shader for removal.
 *
 * @man: Pointer to the compat shader manager
 * @user_key: The key that is used to identify the shader. The key is
 * unique to the shader type.
 * @shader_type: Shader type.
 * @list: Caller's list of staged shader actions.
 *
 * This function stages a compat shader for removal and removes the key from
 * the shader manager's hash table. If the shader was previously only staged
 * for addition it is completely removed (But the execbuf code may keep a
 * reference if it was bound to a context between addition and removal). If
 * it was previously commited to the manager, it is staged for removal.
 */
int vmw_compat_shader_remove(struct vmw_compat_shader_manager *man,
                             u32 user_key, SVGA3dShaderType shader_type,
                             struct list_head *list)
{
        struct vmw_compat_shader *entry;
        struct drm_hash_item *hash;
        int ret;

        ret = drm_ht_find_item(&man->shaders, user_key | (shader_type << 24),
                               &hash);
        if (likely(ret != 0))
                return -EINVAL;

        entry = drm_hash_entry(hash, struct vmw_compat_shader, hash);

        switch (entry->state) {
        case VMW_COMPAT_ADD:
                vmw_compat_shader_free(man, entry);
                break;
        case VMW_COMPAT_COMMITED:
                (void) drm_ht_remove_item(&man->shaders, &entry->hash);
                list_del(&entry->head);
                entry->state = VMW_COMPAT_DEL;
                list_add_tail(&entry->head, list);
                break;
        default:
                BUG();
                break;
        }

        return 0;
}

/**
 * vmw_compat_shader_add - Create a compat shader and add the
 * key to the manager
 *
 * @man: Pointer to the compat shader manager
 * @user_key: The key that is used to identify the shader. The key is
 * unique to the shader type.
 * @bytecode: Pointer to the bytecode of the shader.
 * @shader_type: Shader type.
 * @tfile: Pointer to a struct ttm_object_file that the guest-backed shader is
 * to be created with.
 * @list: Caller's list of staged shader actions.
 *
 * Note that only the key is added to the shader manager's hash table.
 * The shader is not yet added to the shader manager's list of shaders.
 */
int vmw_compat_shader_add(struct vmw_compat_shader_manager *man,
                          u32 user_key, const void *bytecode,
                          SVGA3dShaderType shader_type,
                          size_t size,
                          struct ttm_object_file *tfile,
                          struct list_head *list)
{
        struct vmw_dma_buffer *buf;
        struct ttm_bo_kmap_obj map;
        bool is_iomem;
        struct vmw_compat_shader *compat;
        u32 handle;
        int ret;

        if (user_key > ((1 << 24) - 1) || (unsigned) shader_type > 16)
                return -EINVAL;

        /* Allocate and pin a DMA buffer */
        buf = kzalloc(sizeof(*buf), GFP_KERNEL);
        if (unlikely(buf == NULL))
                return -ENOMEM;

        ret = vmw_dmabuf_init(man->dev_priv, buf, size, &vmw_sys_ne_placement,
                              true, vmw_dmabuf_bo_free);
        if (unlikely(ret != 0))
                goto out;

        ret = ttm_bo_reserve(&buf->base, false, true, false, NULL);
        if (unlikely(ret != 0))
                goto no_reserve;

        /* Map and copy shader bytecode. */
        ret = ttm_bo_kmap(&buf->base, 0, PAGE_ALIGN(size) >> PAGE_SHIFT,
                          &map);
        if (unlikely(ret != 0)) {
                ttm_bo_unreserve(&buf->base);
                goto no_reserve;
        }

        memcpy(ttm_kmap_obj_virtual(&map, &is_iomem), bytecode, size);
        WARN_ON(is_iomem);

        ttm_bo_kunmap(&map);
        ret = ttm_bo_validate(&buf->base, &vmw_sys_placement, false, true);
        WARN_ON(ret != 0);
        ttm_bo_unreserve(&buf->base);

        /* Create a guest-backed shader container backed by the dma buffer */
        ret = vmw_shader_alloc(man->dev_priv, buf, size, 0, shader_type,
                               tfile, &handle);
        vmw_dmabuf_unreference(&buf);
        if (unlikely(ret != 0))
                goto no_reserve;
        /*
         * Create a compat shader structure and stage it for insertion
         * in the manager
         */
        compat = kzalloc(sizeof(*compat), GFP_KERNEL);
        if (compat == NULL)
                goto no_compat;

        compat->hash.key = user_key |  (shader_type << 24);
        ret = drm_ht_insert_item(&man->shaders, &compat->hash);
        if (unlikely(ret != 0))
                goto out_invalid_key;

        compat->state = VMW_COMPAT_ADD;
        compat->handle = handle;
        compat->tfile = tfile;
        list_add_tail(&compat->head, list);

        return 0;

out_invalid_key:
        kfree(compat);
no_compat:
        ttm_ref_object_base_unref(tfile, handle, TTM_REF_USAGE);
no_reserve:
out:
        return ret;
}

/**
 * vmw_compat_shader_man_create - Create a compat shader manager
 *
 * @dev_priv: Pointer to a device private structure.
 *
 * Typically done at file open time. If successful returns a pointer to a
 * compat shader manager. Otherwise returns an error pointer.
 */
struct vmw_compat_shader_manager *
vmw_compat_shader_man_create(struct vmw_private *dev_priv)
{
        struct vmw_compat_shader_manager *man;
        int ret;

        man = kzalloc(sizeof(*man), GFP_KERNEL);

        man->dev_priv = dev_priv;
        INIT_LIST_HEAD(&man->list);
        ret = drm_ht_create(&man->shaders, VMW_COMPAT_SHADER_HT_ORDER);
        if (ret == 0)
                return man;

        kfree(man);
        return ERR_PTR(ret);
}

/**
 * vmw_compat_shader_man_destroy - Destroy a compat shader manager
 *
 * @man: Pointer to the shader manager to destroy.
 *
 * Typically done at file close time.
 */
void vmw_compat_shader_man_destroy(struct vmw_compat_shader_manager *man)
{
        struct vmw_compat_shader *entry, *next;

        mutex_lock(&man->dev_priv->cmdbuf_mutex);
        list_for_each_entry_safe(entry, next, &man->list, head)
                vmw_compat_shader_free(man, entry);

        mutex_unlock(&man->dev_priv->cmdbuf_mutex);
        kfree(man);
}