blob: 0488042fb287b1f35a2a6bd705a58729bbfc4783 [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0 OR MIT
/**************************************************************************
*
* Copyright 2009-2015 VMware, Inc., Palo Alto, CA., USA
*
* 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 <drm/ttm/ttm_bo_driver.h>
#include <drm/ttm/ttm_placement.h>
static const struct ttm_place vram_placement_flags = {
.fpfn = 0,
.lpfn = 0,
.mem_type = TTM_PL_VRAM,
.flags = 0
};
static const struct ttm_place sys_placement_flags = {
.fpfn = 0,
.lpfn = 0,
.mem_type = TTM_PL_SYSTEM,
.flags = 0
};
static const struct ttm_place gmr_placement_flags = {
.fpfn = 0,
.lpfn = 0,
.mem_type = VMW_PL_GMR,
.flags = 0
};
static const struct ttm_place mob_placement_flags = {
.fpfn = 0,
.lpfn = 0,
.mem_type = VMW_PL_MOB,
.flags = 0
};
struct ttm_placement vmw_vram_placement = {
.num_placement = 1,
.placement = &vram_placement_flags,
.num_busy_placement = 1,
.busy_placement = &vram_placement_flags
};
static const struct ttm_place vram_gmr_placement_flags[] = {
{
.fpfn = 0,
.lpfn = 0,
.mem_type = TTM_PL_VRAM,
.flags = 0
}, {
.fpfn = 0,
.lpfn = 0,
.mem_type = VMW_PL_GMR,
.flags = 0
}
};
static const struct ttm_place gmr_vram_placement_flags[] = {
{
.fpfn = 0,
.lpfn = 0,
.mem_type = VMW_PL_GMR,
.flags = 0
}, {
.fpfn = 0,
.lpfn = 0,
.mem_type = TTM_PL_VRAM,
.flags = 0
}
};
struct ttm_placement vmw_vram_gmr_placement = {
.num_placement = 2,
.placement = vram_gmr_placement_flags,
.num_busy_placement = 1,
.busy_placement = &gmr_placement_flags
};
struct ttm_placement vmw_vram_sys_placement = {
.num_placement = 1,
.placement = &vram_placement_flags,
.num_busy_placement = 1,
.busy_placement = &sys_placement_flags
};
struct ttm_placement vmw_sys_placement = {
.num_placement = 1,
.placement = &sys_placement_flags,
.num_busy_placement = 1,
.busy_placement = &sys_placement_flags
};
static const struct ttm_place evictable_placement_flags[] = {
{
.fpfn = 0,
.lpfn = 0,
.mem_type = TTM_PL_SYSTEM,
.flags = 0
}, {
.fpfn = 0,
.lpfn = 0,
.mem_type = TTM_PL_VRAM,
.flags = 0
}, {
.fpfn = 0,
.lpfn = 0,
.mem_type = VMW_PL_GMR,
.flags = 0
}, {
.fpfn = 0,
.lpfn = 0,
.mem_type = VMW_PL_MOB,
.flags = 0
}
};
static const struct ttm_place nonfixed_placement_flags[] = {
{
.fpfn = 0,
.lpfn = 0,
.mem_type = TTM_PL_SYSTEM,
.flags = 0
}, {
.fpfn = 0,
.lpfn = 0,
.mem_type = VMW_PL_GMR,
.flags = 0
}, {
.fpfn = 0,
.lpfn = 0,
.mem_type = VMW_PL_MOB,
.flags = 0
}
};
struct ttm_placement vmw_evictable_placement = {
.num_placement = 4,
.placement = evictable_placement_flags,
.num_busy_placement = 1,
.busy_placement = &sys_placement_flags
};
struct ttm_placement vmw_srf_placement = {
.num_placement = 1,
.num_busy_placement = 2,
.placement = &gmr_placement_flags,
.busy_placement = gmr_vram_placement_flags
};
struct ttm_placement vmw_mob_placement = {
.num_placement = 1,
.num_busy_placement = 1,
.placement = &mob_placement_flags,
.busy_placement = &mob_placement_flags
};
struct ttm_placement vmw_nonfixed_placement = {
.num_placement = 3,
.placement = nonfixed_placement_flags,
.num_busy_placement = 1,
.busy_placement = &sys_placement_flags
};
struct vmw_ttm_tt {
struct ttm_tt dma_ttm;
struct vmw_private *dev_priv;
int gmr_id;
struct vmw_mob *mob;
int mem_type;
struct sg_table sgt;
struct vmw_sg_table vsgt;
uint64_t sg_alloc_size;
bool mapped;
bool bound;
};
const size_t vmw_tt_size = sizeof(struct vmw_ttm_tt);
/**
* __vmw_piter_non_sg_next: Helper functions to advance
* a struct vmw_piter iterator.
*
* @viter: Pointer to the iterator.
*
* These functions return false if past the end of the list,
* true otherwise. Functions are selected depending on the current
* DMA mapping mode.
*/
static bool __vmw_piter_non_sg_next(struct vmw_piter *viter)
{
return ++(viter->i) < viter->num_pages;
}
static bool __vmw_piter_sg_next(struct vmw_piter *viter)
{
bool ret = __vmw_piter_non_sg_next(viter);
return __sg_page_iter_dma_next(&viter->iter) && ret;
}
/**
* __vmw_piter_non_sg_page: Helper functions to return a pointer
* to the current page.
*
* @viter: Pointer to the iterator
*
* These functions return a pointer to the page currently
* pointed to by @viter. Functions are selected depending on the
* current mapping mode.
*/
static struct page *__vmw_piter_non_sg_page(struct vmw_piter *viter)
{
return viter->pages[viter->i];
}
/**
* __vmw_piter_phys_addr: Helper functions to return the DMA
* address of the current page.
*
* @viter: Pointer to the iterator
*
* These functions return the DMA address of the page currently
* pointed to by @viter. Functions are selected depending on the
* current mapping mode.
*/
static dma_addr_t __vmw_piter_phys_addr(struct vmw_piter *viter)
{
return page_to_phys(viter->pages[viter->i]);
}
static dma_addr_t __vmw_piter_dma_addr(struct vmw_piter *viter)
{
return viter->addrs[viter->i];
}
static dma_addr_t __vmw_piter_sg_addr(struct vmw_piter *viter)
{
return sg_page_iter_dma_address(&viter->iter);
}
/**
* vmw_piter_start - Initialize a struct vmw_piter.
*
* @viter: Pointer to the iterator to initialize
* @vsgt: Pointer to a struct vmw_sg_table to initialize from
* @p_offset: Pointer offset used to update current array position
*
* Note that we're following the convention of __sg_page_iter_start, so that
* the iterator doesn't point to a valid page after initialization; it has
* to be advanced one step first.
*/
void vmw_piter_start(struct vmw_piter *viter, const struct vmw_sg_table *vsgt,
unsigned long p_offset)
{
viter->i = p_offset - 1;
viter->num_pages = vsgt->num_pages;
viter->page = &__vmw_piter_non_sg_page;
viter->pages = vsgt->pages;
switch (vsgt->mode) {
case vmw_dma_phys:
viter->next = &__vmw_piter_non_sg_next;
viter->dma_address = &__vmw_piter_phys_addr;
break;
case vmw_dma_alloc_coherent:
viter->next = &__vmw_piter_non_sg_next;
viter->dma_address = &__vmw_piter_dma_addr;
viter->addrs = vsgt->addrs;
break;
case vmw_dma_map_populate:
case vmw_dma_map_bind:
viter->next = &__vmw_piter_sg_next;
viter->dma_address = &__vmw_piter_sg_addr;
__sg_page_iter_start(&viter->iter.base, vsgt->sgt->sgl,
vsgt->sgt->orig_nents, p_offset);
break;
default:
BUG();
}
}
/**
* vmw_ttm_unmap_from_dma - unmap device addresses previsouly mapped for
* TTM pages
*
* @vmw_tt: Pointer to a struct vmw_ttm_backend
*
* Used to free dma mappings previously mapped by vmw_ttm_map_for_dma.
*/
static void vmw_ttm_unmap_from_dma(struct vmw_ttm_tt *vmw_tt)
{
struct device *dev = vmw_tt->dev_priv->drm.dev;
dma_unmap_sgtable(dev, &vmw_tt->sgt, DMA_BIDIRECTIONAL, 0);
vmw_tt->sgt.nents = vmw_tt->sgt.orig_nents;
}
/**
* vmw_ttm_map_for_dma - map TTM pages to get device addresses
*
* @vmw_tt: Pointer to a struct vmw_ttm_backend
*
* This function is used to get device addresses from the kernel DMA layer.
* However, it's violating the DMA API in that when this operation has been
* performed, it's illegal for the CPU to write to the pages without first
* unmapping the DMA mappings, or calling dma_sync_sg_for_cpu(). It is
* therefore only legal to call this function if we know that the function
* dma_sync_sg_for_cpu() is a NOP, and dma_sync_sg_for_device() is at most
* a CPU write buffer flush.
*/
static int vmw_ttm_map_for_dma(struct vmw_ttm_tt *vmw_tt)
{
struct device *dev = vmw_tt->dev_priv->drm.dev;
return dma_map_sgtable(dev, &vmw_tt->sgt, DMA_BIDIRECTIONAL, 0);
}
/**
* vmw_ttm_map_dma - Make sure TTM pages are visible to the device
*
* @vmw_tt: Pointer to a struct vmw_ttm_tt
*
* Select the correct function for and make sure the TTM pages are
* visible to the device. Allocate storage for the device mappings.
* If a mapping has already been performed, indicated by the storage
* pointer being non NULL, the function returns success.
*/
static int vmw_ttm_map_dma(struct vmw_ttm_tt *vmw_tt)
{
struct vmw_private *dev_priv = vmw_tt->dev_priv;
struct ttm_mem_global *glob = vmw_mem_glob(dev_priv);
struct vmw_sg_table *vsgt = &vmw_tt->vsgt;
struct ttm_operation_ctx ctx = {
.interruptible = true,
.no_wait_gpu = false
};
struct vmw_piter iter;
dma_addr_t old;
int ret = 0;
static size_t sgl_size;
static size_t sgt_size;
struct scatterlist *sg;
if (vmw_tt->mapped)
return 0;
vsgt->mode = dev_priv->map_mode;
vsgt->pages = vmw_tt->dma_ttm.pages;
vsgt->num_pages = vmw_tt->dma_ttm.num_pages;
vsgt->addrs = vmw_tt->dma_ttm.dma_address;
vsgt->sgt = &vmw_tt->sgt;
switch (dev_priv->map_mode) {
case vmw_dma_map_bind:
case vmw_dma_map_populate:
if (unlikely(!sgl_size)) {
sgl_size = ttm_round_pot(sizeof(struct scatterlist));
sgt_size = ttm_round_pot(sizeof(struct sg_table));
}
vmw_tt->sg_alloc_size = sgt_size + sgl_size * vsgt->num_pages;
ret = ttm_mem_global_alloc(glob, vmw_tt->sg_alloc_size, &ctx);
if (unlikely(ret != 0))
return ret;
sg = __sg_alloc_table_from_pages(&vmw_tt->sgt, vsgt->pages,
vsgt->num_pages, 0,
(unsigned long) vsgt->num_pages << PAGE_SHIFT,
dma_get_max_seg_size(dev_priv->drm.dev),
NULL, 0, GFP_KERNEL);
if (IS_ERR(sg)) {
ret = PTR_ERR(sg);
goto out_sg_alloc_fail;
}
if (vsgt->num_pages > vmw_tt->sgt.orig_nents) {
uint64_t over_alloc =
sgl_size * (vsgt->num_pages -
vmw_tt->sgt.orig_nents);
ttm_mem_global_free(glob, over_alloc);
vmw_tt->sg_alloc_size -= over_alloc;
}
ret = vmw_ttm_map_for_dma(vmw_tt);
if (unlikely(ret != 0))
goto out_map_fail;
break;
default:
break;
}
old = ~((dma_addr_t) 0);
vmw_tt->vsgt.num_regions = 0;
for (vmw_piter_start(&iter, vsgt, 0); vmw_piter_next(&iter);) {
dma_addr_t cur = vmw_piter_dma_addr(&iter);
if (cur != old + PAGE_SIZE)
vmw_tt->vsgt.num_regions++;
old = cur;
}
vmw_tt->mapped = true;
return 0;
out_map_fail:
sg_free_table(vmw_tt->vsgt.sgt);
vmw_tt->vsgt.sgt = NULL;
out_sg_alloc_fail:
ttm_mem_global_free(glob, vmw_tt->sg_alloc_size);
return ret;
}
/**
* vmw_ttm_unmap_dma - Tear down any TTM page device mappings
*
* @vmw_tt: Pointer to a struct vmw_ttm_tt
*
* Tear down any previously set up device DMA mappings and free
* any storage space allocated for them. If there are no mappings set up,
* this function is a NOP.
*/
static void vmw_ttm_unmap_dma(struct vmw_ttm_tt *vmw_tt)
{
struct vmw_private *dev_priv = vmw_tt->dev_priv;
if (!vmw_tt->vsgt.sgt)
return;
switch (dev_priv->map_mode) {
case vmw_dma_map_bind:
case vmw_dma_map_populate:
vmw_ttm_unmap_from_dma(vmw_tt);
sg_free_table(vmw_tt->vsgt.sgt);
vmw_tt->vsgt.sgt = NULL;
ttm_mem_global_free(vmw_mem_glob(dev_priv),
vmw_tt->sg_alloc_size);
break;
default:
break;
}
vmw_tt->mapped = false;
}
/**
* vmw_bo_sg_table - Return a struct vmw_sg_table object for a
* TTM buffer object
*
* @bo: Pointer to a struct ttm_buffer_object
*
* Returns a pointer to a struct vmw_sg_table object. The object should
* not be freed after use.
* Note that for the device addresses to be valid, the buffer object must
* either be reserved or pinned.
*/
const struct vmw_sg_table *vmw_bo_sg_table(struct ttm_buffer_object *bo)
{
struct vmw_ttm_tt *vmw_tt =
container_of(bo->ttm, struct vmw_ttm_tt, dma_ttm);
return &vmw_tt->vsgt;
}
static int vmw_ttm_bind(struct ttm_device *bdev,
struct ttm_tt *ttm, struct ttm_resource *bo_mem)
{
struct vmw_ttm_tt *vmw_be =
container_of(ttm, struct vmw_ttm_tt, dma_ttm);
int ret = 0;
if (!bo_mem)
return -EINVAL;
if (vmw_be->bound)
return 0;
ret = vmw_ttm_map_dma(vmw_be);
if (unlikely(ret != 0))
return ret;
vmw_be->gmr_id = bo_mem->start;
vmw_be->mem_type = bo_mem->mem_type;
switch (bo_mem->mem_type) {
case VMW_PL_GMR:
ret = vmw_gmr_bind(vmw_be->dev_priv, &vmw_be->vsgt,
ttm->num_pages, vmw_be->gmr_id);
break;
case VMW_PL_MOB:
if (unlikely(vmw_be->mob == NULL)) {
vmw_be->mob =
vmw_mob_create(ttm->num_pages);
if (unlikely(vmw_be->mob == NULL))
return -ENOMEM;
}
ret = vmw_mob_bind(vmw_be->dev_priv, vmw_be->mob,
&vmw_be->vsgt, ttm->num_pages,
vmw_be->gmr_id);
break;
default:
BUG();
}
vmw_be->bound = true;
return ret;
}
static void vmw_ttm_unbind(struct ttm_device *bdev,
struct ttm_tt *ttm)
{
struct vmw_ttm_tt *vmw_be =
container_of(ttm, struct vmw_ttm_tt, dma_ttm);
if (!vmw_be->bound)
return;
switch (vmw_be->mem_type) {
case VMW_PL_GMR:
vmw_gmr_unbind(vmw_be->dev_priv, vmw_be->gmr_id);
break;
case VMW_PL_MOB:
vmw_mob_unbind(vmw_be->dev_priv, vmw_be->mob);
break;
default:
BUG();
}
if (vmw_be->dev_priv->map_mode == vmw_dma_map_bind)
vmw_ttm_unmap_dma(vmw_be);
vmw_be->bound = false;
}
static void vmw_ttm_destroy(struct ttm_device *bdev, struct ttm_tt *ttm)
{
struct vmw_ttm_tt *vmw_be =
container_of(ttm, struct vmw_ttm_tt, dma_ttm);
vmw_ttm_unbind(bdev, ttm);
ttm_tt_destroy_common(bdev, ttm);
vmw_ttm_unmap_dma(vmw_be);
if (vmw_be->dev_priv->map_mode == vmw_dma_alloc_coherent)
ttm_tt_fini(&vmw_be->dma_ttm);
else
ttm_tt_fini(ttm);
if (vmw_be->mob)
vmw_mob_destroy(vmw_be->mob);
kfree(vmw_be);
}
static int vmw_ttm_populate(struct ttm_device *bdev,
struct ttm_tt *ttm, struct ttm_operation_ctx *ctx)
{
unsigned int i;
int ret;
/* TODO: maybe completely drop this ? */
if (ttm_tt_is_populated(ttm))
return 0;
ret = ttm_pool_alloc(&bdev->pool, ttm, ctx);
if (ret)
return ret;
for (i = 0; i < ttm->num_pages; ++i) {
ret = ttm_mem_global_alloc_page(&ttm_mem_glob, ttm->pages[i],
PAGE_SIZE, ctx);
if (ret)
goto error;
}
return 0;
error:
while (i--)
ttm_mem_global_free_page(&ttm_mem_glob, ttm->pages[i],
PAGE_SIZE);
ttm_pool_free(&bdev->pool, ttm);
return ret;
}
static void vmw_ttm_unpopulate(struct ttm_device *bdev,
struct ttm_tt *ttm)
{
struct vmw_ttm_tt *vmw_tt = container_of(ttm, struct vmw_ttm_tt,
dma_ttm);
unsigned int i;
if (vmw_tt->mob) {
vmw_mob_destroy(vmw_tt->mob);
vmw_tt->mob = NULL;
}
vmw_ttm_unmap_dma(vmw_tt);
for (i = 0; i < ttm->num_pages; ++i)
ttm_mem_global_free_page(&ttm_mem_glob, ttm->pages[i],
PAGE_SIZE);
ttm_pool_free(&bdev->pool, ttm);
}
static struct ttm_tt *vmw_ttm_tt_create(struct ttm_buffer_object *bo,
uint32_t page_flags)
{
struct vmw_ttm_tt *vmw_be;
int ret;
vmw_be = kzalloc(sizeof(*vmw_be), GFP_KERNEL);
if (!vmw_be)
return NULL;
vmw_be->dev_priv = container_of(bo->bdev, struct vmw_private, bdev);
vmw_be->mob = NULL;
if (vmw_be->dev_priv->map_mode == vmw_dma_alloc_coherent)
ret = ttm_sg_tt_init(&vmw_be->dma_ttm, bo, page_flags,
ttm_cached);
else
ret = ttm_tt_init(&vmw_be->dma_ttm, bo, page_flags,
ttm_cached);
if (unlikely(ret != 0))
goto out_no_init;
return &vmw_be->dma_ttm;
out_no_init:
kfree(vmw_be);
return NULL;
}
static void vmw_evict_flags(struct ttm_buffer_object *bo,
struct ttm_placement *placement)
{
*placement = vmw_sys_placement;
}
static int vmw_ttm_io_mem_reserve(struct ttm_device *bdev, struct ttm_resource *mem)
{
struct vmw_private *dev_priv = container_of(bdev, struct vmw_private, bdev);
switch (mem->mem_type) {
case TTM_PL_SYSTEM:
case VMW_PL_GMR:
case VMW_PL_MOB:
return 0;
case TTM_PL_VRAM:
mem->bus.offset = (mem->start << PAGE_SHIFT) +
dev_priv->vram_start;
mem->bus.is_iomem = true;
mem->bus.caching = ttm_cached;
break;
default:
return -EINVAL;
}
return 0;
}
/**
* vmw_move_notify - TTM move_notify_callback
*
* @bo: The TTM buffer object about to move.
* @old_mem: The old memory where we move from
* @new_mem: The struct ttm_resource indicating to what memory
* region the move is taking place.
*
* Calls move_notify for all subsystems needing it.
* (currently only resources).
*/
static void vmw_move_notify(struct ttm_buffer_object *bo,
struct ttm_resource *old_mem,
struct ttm_resource *new_mem)
{
vmw_bo_move_notify(bo, new_mem);
vmw_query_move_notify(bo, old_mem, new_mem);
}
/**
* vmw_swap_notify - TTM move_notify_callback
*
* @bo: The TTM buffer object about to be swapped out.
*/
static void vmw_swap_notify(struct ttm_buffer_object *bo)
{
vmw_bo_swap_notify(bo);
(void) ttm_bo_wait(bo, false, false);
}
static int vmw_move(struct ttm_buffer_object *bo,
bool evict,
struct ttm_operation_ctx *ctx,
struct ttm_resource *new_mem,
struct ttm_place *hop)
{
struct ttm_resource_manager *old_man = ttm_manager_type(bo->bdev, bo->resource->mem_type);
struct ttm_resource_manager *new_man = ttm_manager_type(bo->bdev, new_mem->mem_type);
int ret;
if (new_man->use_tt && new_mem->mem_type != TTM_PL_SYSTEM) {
ret = vmw_ttm_bind(bo->bdev, bo->ttm, new_mem);
if (ret)
return ret;
}
vmw_move_notify(bo, bo->resource, new_mem);
if (old_man->use_tt && new_man->use_tt) {
if (bo->resource->mem_type == TTM_PL_SYSTEM) {
ttm_bo_move_null(bo, new_mem);
return 0;
}
ret = ttm_bo_wait_ctx(bo, ctx);
if (ret)
goto fail;
vmw_ttm_unbind(bo->bdev, bo->ttm);
ttm_resource_free(bo, &bo->resource);
ttm_bo_assign_mem(bo, new_mem);
return 0;
} else {
ret = ttm_bo_move_memcpy(bo, ctx, new_mem);
if (ret)
goto fail;
}
return 0;
fail:
vmw_move_notify(bo, new_mem, bo->resource);
return ret;
}
struct ttm_device_funcs vmw_bo_driver = {
.ttm_tt_create = &vmw_ttm_tt_create,
.ttm_tt_populate = &vmw_ttm_populate,
.ttm_tt_unpopulate = &vmw_ttm_unpopulate,
.ttm_tt_destroy = &vmw_ttm_destroy,
.eviction_valuable = ttm_bo_eviction_valuable,
.evict_flags = vmw_evict_flags,
.move = vmw_move,
.swap_notify = vmw_swap_notify,
.io_mem_reserve = &vmw_ttm_io_mem_reserve,
};
int vmw_bo_create_and_populate(struct vmw_private *dev_priv,
unsigned long bo_size,
struct ttm_buffer_object **bo_p)
{
struct ttm_operation_ctx ctx = {
.interruptible = false,
.no_wait_gpu = false
};
struct ttm_buffer_object *bo;
int ret;
ret = vmw_bo_create_kernel(dev_priv, bo_size,
&vmw_sys_placement,
&bo);
if (unlikely(ret != 0))
return ret;
ret = ttm_bo_reserve(bo, false, true, NULL);
BUG_ON(ret != 0);
ret = vmw_ttm_populate(bo->bdev, bo->ttm, &ctx);
if (likely(ret == 0)) {
struct vmw_ttm_tt *vmw_tt =
container_of(bo->ttm, struct vmw_ttm_tt, dma_ttm);
ret = vmw_ttm_map_dma(vmw_tt);
}
ttm_bo_unreserve(bo);
if (likely(ret == 0))
*bo_p = bo;
return ret;
}