/* SPDX-License-Identifier: GPL-2.0 OR MIT */
/**************************************************************************
*
* Copyright (c) 2006-2009 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.
*
**************************************************************************/
/*
* Authors: Thomas Hellstrom <thellstrom-at-vmware-dot-com>
*/
#define pr_fmt(fmt) "[TTM] " fmt
#include <linux/cc_platform.h>
#include <linux/debugfs.h>
#include <linux/file.h>
#include <linux/module.h>
#include <linux/sched.h>
#include <linux/shmem_fs.h>
#include <drm/drm_cache.h>
#include <drm/drm_device.h>
#include <drm/drm_util.h>
#include <drm/ttm/ttm_bo.h>
#include <drm/ttm/ttm_tt.h>
#include "ttm_module.h"
static unsigned long ttm_pages_limit;
MODULE_PARM_DESC(pages_limit, "Limit for the allocated pages");
module_param_named(pages_limit, ttm_pages_limit, ulong, 0644);
static unsigned long ttm_dma32_pages_limit;
MODULE_PARM_DESC(dma32_pages_limit, "Limit for the allocated DMA32 pages");
module_param_named(dma32_pages_limit, ttm_dma32_pages_limit, ulong, 0644);
static atomic_long_t ttm_pages_allocated;
static atomic_long_t ttm_dma32_pages_allocated;
/*
* Allocates a ttm structure for the given BO.
*/
int ttm_tt_create(struct ttm_buffer_object *bo, bool zero_alloc)
{
struct ttm_device *bdev = bo->bdev;
struct drm_device *ddev = bo->base.dev;
uint32_t page_flags = 0;
dma_resv_assert_held(bo->base.resv);
if (bo->ttm)
return 0;
switch (bo->type) {
case ttm_bo_type_device:
if (zero_alloc)
page_flags |= TTM_TT_FLAG_ZERO_ALLOC;
break;
case ttm_bo_type_kernel:
break;
case ttm_bo_type_sg:
page_flags |= TTM_TT_FLAG_EXTERNAL;
break;
default:
pr_err("Illegal buffer object type\n");
return -EINVAL;
}
/*
* When using dma_alloc_coherent with memory encryption the
* mapped TT pages need to be decrypted or otherwise the drivers
* will end up sending encrypted mem to the gpu.
*/
if (bdev->pool.use_dma_alloc && cc_platform_has(CC_ATTR_GUEST_MEM_ENCRYPT)) {
page_flags |= TTM_TT_FLAG_DECRYPTED;
drm_info_once(ddev, "TT memory decryption enabled.");
}
bo->ttm = bdev->funcs->ttm_tt_create(bo, page_flags);
if (unlikely(bo->ttm == NULL))
return -ENOMEM;
WARN_ON(bo->ttm->page_flags & TTM_TT_FLAG_EXTERNAL_MAPPABLE &&
!(bo->ttm->page_flags & TTM_TT_FLAG_EXTERNAL));
return 0;
}
EXPORT_SYMBOL_FOR_TESTS_ONLY(ttm_tt_create);
/*
* Allocates storage for pointers to the pages that back the ttm.
*/
static int ttm_tt_alloc_page_directory(struct ttm_tt *ttm)
{
ttm->pages = kvcalloc(ttm->num_pages, sizeof(void*), GFP_KERNEL);
if (!ttm->pages)
return -ENOMEM;
return 0;
}
static int ttm_dma_tt_alloc_page_directory(struct ttm_tt *ttm)
{
ttm->pages = kvcalloc(ttm->num_pages, sizeof(*ttm->pages) +
sizeof(*ttm->dma_address), GFP_KERNEL);
if (!ttm->pages)
return -ENOMEM;
ttm->dma_address = (void *)(ttm->pages + ttm->num_pages);
return 0;
}
static int ttm_sg_tt_alloc_page_directory(struct ttm_tt *ttm)
{
ttm->dma_address = kvcalloc(ttm->num_pages, sizeof(*ttm->dma_address),
GFP_KERNEL);
if (!ttm->dma_address)
return -ENOMEM;
return 0;
}
void ttm_tt_destroy(struct ttm_device *bdev, struct ttm_tt *ttm)
{
bdev->funcs->ttm_tt_destroy(bdev, ttm);
}
EXPORT_SYMBOL_FOR_TESTS_ONLY(ttm_tt_destroy);
static void ttm_tt_init_fields(struct ttm_tt *ttm,
struct ttm_buffer_object *bo,
uint32_t page_flags,
enum ttm_caching caching,
unsigned long extra_pages)
{
ttm->num_pages = (PAGE_ALIGN(bo->base.size) >> PAGE_SHIFT) + extra_pages;
ttm->page_flags = page_flags;
ttm->dma_address = NULL;
ttm->swap_storage = NULL;
ttm->sg = bo->sg;
ttm->caching = caching;
}
int ttm_tt_init(struct ttm_tt *ttm, struct ttm_buffer_object *bo,
uint32_t page_flags, enum ttm_caching caching,
unsigned long extra_pages)
{
ttm_tt_init_fields(ttm, bo, page_flags, caching, extra_pages);
if (ttm_tt_alloc_page_directory(ttm)) {
pr_err("Failed allocating page table\n");
return -ENOMEM;
}
return 0;
}
EXPORT_SYMBOL(ttm_tt_init);
void ttm_tt_fini(struct ttm_tt *ttm)
{
WARN_ON(ttm->page_flags & TTM_TT_FLAG_PRIV_POPULATED);
if (ttm->swap_storage)
fput(ttm->swap_storage);
ttm->swap_storage = NULL;
if (ttm->pages)
kvfree(ttm->pages);
else
kvfree(ttm->dma_address);
ttm->pages = NULL;
ttm->dma_address = NULL;
}
EXPORT_SYMBOL(ttm_tt_fini);
int ttm_sg_tt_init(struct ttm_tt *ttm, struct ttm_buffer_object *bo,
uint32_t page_flags, enum ttm_caching caching)
{
int ret;
ttm_tt_init_fields(ttm, bo, page_flags, caching, 0);
if (page_flags & TTM_TT_FLAG_EXTERNAL)
ret = ttm_sg_tt_alloc_page_directory(ttm);
else
ret = ttm_dma_tt_alloc_page_directory(ttm);
if (ret) {
pr_err("Failed allocating page table\n");
return -ENOMEM;
}
return 0;
}
EXPORT_SYMBOL(ttm_sg_tt_init);
int ttm_tt_swapin(struct ttm_tt *ttm)
{
struct address_space *swap_space;
struct file *swap_storage;
struct page *from_page;
struct page *to_page;
gfp_t gfp_mask;
int i, ret;
swap_storage = ttm->swap_storage;
BUG_ON(swap_storage == NULL);
swap_space = swap_storage->f_mapping;
gfp_mask = mapping_gfp_mask(swap_space);
for (i = 0; i < ttm->num_pages; ++i) {
from_page = shmem_read_mapping_page_gfp(swap_space, i,
gfp_mask);
if (IS_ERR(from_page)) {
ret = PTR_ERR(from_page);
goto out_err;
}
to_page = ttm->pages[i];
if (unlikely(to_page == NULL)) {
ret = -ENOMEM;
goto out_err;
}
copy_highpage(to_page, from_page);
put_page(from_page);
}
fput(swap_storage);
ttm->swap_storage = NULL;
ttm->page_flags &= ~TTM_TT_FLAG_SWAPPED;
return 0;
out_err:
return ret;
}
EXPORT_SYMBOL_FOR_TESTS_ONLY(ttm_tt_swapin);
/**
* ttm_tt_swapout - swap out tt object
*
* @bdev: TTM device structure.
* @ttm: The struct ttm_tt.
* @gfp_flags: Flags to use for memory allocation.
*
* Swapout a TT object to a shmem_file, return number of pages swapped out or
* negative error code.
*/
int ttm_tt_swapout(struct ttm_device *bdev, struct ttm_tt *ttm,
gfp_t gfp_flags)
{
loff_t size = (loff_t)ttm->num_pages << PAGE_SHIFT;
struct address_space *swap_space;
struct file *swap_storage;
struct page *from_page;
struct page *to_page;
int i, ret;
swap_storage = shmem_file_setup("ttm swap", size, 0);
if (IS_ERR(swap_storage)) {
pr_err("Failed allocating swap storage\n");
return PTR_ERR(swap_storage);
}
swap_space = swap_storage->f_mapping;
gfp_flags &= mapping_gfp_mask(swap_space);
for (i = 0; i < ttm->num_pages; ++i) {
from_page = ttm->pages[i];
if (unlikely(from_page == NULL))
continue;
to_page = shmem_read_mapping_page_gfp(swap_space, i, gfp_flags);
if (IS_ERR(to_page)) {
ret = PTR_ERR(to_page);
goto out_err;
}
copy_highpage(to_page, from_page);
set_page_dirty(to_page);
mark_page_accessed(to_page);
put_page(to_page);
}
ttm_tt_unpopulate(bdev, ttm);
ttm->swap_storage = swap_storage;
ttm->page_flags |= TTM_TT_FLAG_SWAPPED;
return ttm->num_pages;
out_err:
fput(swap_storage);
return ret;
}
EXPORT_SYMBOL_FOR_TESTS_ONLY(ttm_tt_swapout);
int ttm_tt_populate(struct ttm_device *bdev,
struct ttm_tt *ttm, struct ttm_operation_ctx *ctx)
{
int ret;
if (!ttm)
return -EINVAL;
if (ttm_tt_is_populated(ttm))
return 0;
if (!(ttm->page_flags & TTM_TT_FLAG_EXTERNAL)) {
atomic_long_add(ttm->num_pages, &ttm_pages_allocated);
if (bdev->pool.use_dma32)
atomic_long_add(ttm->num_pages,
&ttm_dma32_pages_allocated);
}
while (atomic_long_read(&ttm_pages_allocated) > ttm_pages_limit ||
atomic_long_read(&ttm_dma32_pages_allocated) >
ttm_dma32_pages_limit) {
ret = ttm_global_swapout(ctx, GFP_KERNEL);
if (ret == 0)
break;
if (ret < 0)
goto error;
}
if (bdev->funcs->ttm_tt_populate)
ret = bdev->funcs->ttm_tt_populate(bdev, ttm, ctx);
else
ret = ttm_pool_alloc(&bdev->pool, ttm, ctx);
if (ret)
goto error;
ttm->page_flags |= TTM_TT_FLAG_PRIV_POPULATED;
if (unlikely(ttm->page_flags & TTM_TT_FLAG_SWAPPED)) {
ret = ttm_tt_swapin(ttm);
if (unlikely(ret != 0)) {
ttm_tt_unpopulate(bdev, ttm);
return ret;
}
}
return 0;
error:
if (!(ttm->page_flags & TTM_TT_FLAG_EXTERNAL)) {
atomic_long_sub(ttm->num_pages, &ttm_pages_allocated);
if (bdev->pool.use_dma32)
atomic_long_sub(ttm->num_pages,
&ttm_dma32_pages_allocated);
}
return ret;
}
EXPORT_SYMBOL(ttm_tt_populate);
void ttm_tt_unpopulate(struct ttm_device *bdev, struct ttm_tt *ttm)
{
if (!ttm_tt_is_populated(ttm))
return;
if (bdev->funcs->ttm_tt_unpopulate)
bdev->funcs->ttm_tt_unpopulate(bdev, ttm);
else
ttm_pool_free(&bdev->pool, ttm);
if (!(ttm->page_flags & TTM_TT_FLAG_EXTERNAL)) {
atomic_long_sub(ttm->num_pages, &ttm_pages_allocated);
if (bdev->pool.use_dma32)
atomic_long_sub(ttm->num_pages,
&ttm_dma32_pages_allocated);
}
ttm->page_flags &= ~TTM_TT_FLAG_PRIV_POPULATED;
}
EXPORT_SYMBOL_FOR_TESTS_ONLY(ttm_tt_unpopulate);
#ifdef CONFIG_DEBUG_FS
/* Test the shrinker functions and dump the result */
static int ttm_tt_debugfs_shrink_show(struct seq_file *m, void *data)
{
struct ttm_operation_ctx ctx = { false, false };
seq_printf(m, "%d\n", ttm_global_swapout(&ctx, GFP_KERNEL));
return 0;
}
DEFINE_SHOW_ATTRIBUTE(ttm_tt_debugfs_shrink);
#endif
/*
* ttm_tt_mgr_init - register with the MM shrinker
*
* Register with the MM shrinker for swapping out BOs.
*/
void ttm_tt_mgr_init(unsigned long num_pages, unsigned long num_dma32_pages)
{
#ifdef CONFIG_DEBUG_FS
debugfs_create_file("tt_shrink", 0400, ttm_debugfs_root, NULL,
&ttm_tt_debugfs_shrink_fops);
#endif
if (!ttm_pages_limit)
ttm_pages_limit = num_pages;
if (!ttm_dma32_pages_limit)
ttm_dma32_pages_limit = num_dma32_pages;
}
static void ttm_kmap_iter_tt_map_local(struct ttm_kmap_iter *iter,
struct iosys_map *dmap,
pgoff_t i)
{
struct ttm_kmap_iter_tt *iter_tt =
container_of(iter, typeof(*iter_tt), base);
iosys_map_set_vaddr(dmap, kmap_local_page_prot(iter_tt->tt->pages[i],
iter_tt->prot));
}
static void ttm_kmap_iter_tt_unmap_local(struct ttm_kmap_iter *iter,
struct iosys_map *map)
{
kunmap_local(map->vaddr);
}
static const struct ttm_kmap_iter_ops ttm_kmap_iter_tt_ops = {
.map_local = ttm_kmap_iter_tt_map_local,
.unmap_local = ttm_kmap_iter_tt_unmap_local,
.maps_tt = true,
};
/**
* ttm_kmap_iter_tt_init - Initialize a struct ttm_kmap_iter_tt
* @iter_tt: The struct ttm_kmap_iter_tt to initialize.
* @tt: Struct ttm_tt holding page pointers of the struct ttm_resource.
*
* Return: Pointer to the embedded struct ttm_kmap_iter.
*/
struct ttm_kmap_iter *
ttm_kmap_iter_tt_init(struct ttm_kmap_iter_tt *iter_tt,
struct ttm_tt *tt)
{
iter_tt->base.ops = &ttm_kmap_iter_tt_ops;
iter_tt->tt = tt;
if (tt)
iter_tt->prot = ttm_prot_from_caching(tt->caching, PAGE_KERNEL);
else
iter_tt->prot = PAGE_KERNEL;
return &iter_tt->base;
}
EXPORT_SYMBOL(ttm_kmap_iter_tt_init);
unsigned long ttm_tt_pages_limit(void)
{
return ttm_pages_limit;
}
EXPORT_SYMBOL(ttm_tt_pages_limit);
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