blob: 1e426a42a36c094a69d78d3656c2c1859ea3b8c2 [file] [log] [blame]
/*
* Copyright © 2017 Intel Corporation
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the "Software"),
* to deal in the Software without restriction, including without limitation
* the rights to use, copy, modify, merge, publish, distribute, sublicense,
* and/or sell copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice (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 NONINFRINGEMENT. IN NO EVENT SHALL
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
* IN THE SOFTWARE.
*
*/
#include <linux/sched/mm.h>
#include "display/intel_frontbuffer.h"
#include "pxp/intel_pxp.h"
#include "i915_drv.h"
#include "i915_gem_clflush.h"
#include "i915_gem_context.h"
#include "i915_gem_mman.h"
#include "i915_gem_object.h"
#include "i915_memcpy.h"
#include "i915_trace.h"
static struct kmem_cache *slab_objects;
static const struct drm_gem_object_funcs i915_gem_object_funcs;
struct drm_i915_gem_object *i915_gem_object_alloc(void)
{
struct drm_i915_gem_object *obj;
obj = kmem_cache_zalloc(slab_objects, GFP_KERNEL);
if (!obj)
return NULL;
obj->base.funcs = &i915_gem_object_funcs;
return obj;
}
void i915_gem_object_free(struct drm_i915_gem_object *obj)
{
return kmem_cache_free(slab_objects, obj);
}
void i915_gem_object_init(struct drm_i915_gem_object *obj,
const struct drm_i915_gem_object_ops *ops,
struct lock_class_key *key, unsigned flags)
{
/*
* A gem object is embedded both in a struct ttm_buffer_object :/ and
* in a drm_i915_gem_object. Make sure they are aliased.
*/
BUILD_BUG_ON(offsetof(typeof(*obj), base) !=
offsetof(typeof(*obj), __do_not_access.base));
spin_lock_init(&obj->vma.lock);
INIT_LIST_HEAD(&obj->vma.list);
INIT_LIST_HEAD(&obj->mm.link);
INIT_LIST_HEAD(&obj->lut_list);
spin_lock_init(&obj->lut_lock);
spin_lock_init(&obj->mmo.lock);
obj->mmo.offsets = RB_ROOT;
init_rcu_head(&obj->rcu);
obj->ops = ops;
GEM_BUG_ON(flags & ~I915_BO_ALLOC_FLAGS);
obj->flags = flags;
obj->mm.madv = I915_MADV_WILLNEED;
INIT_RADIX_TREE(&obj->mm.get_page.radix, GFP_KERNEL | __GFP_NOWARN);
mutex_init(&obj->mm.get_page.lock);
INIT_RADIX_TREE(&obj->mm.get_dma_page.radix, GFP_KERNEL | __GFP_NOWARN);
mutex_init(&obj->mm.get_dma_page.lock);
}
/**
* i915_gem_object_fini - Clean up a GEM object initialization
* @obj: The gem object to cleanup
*
* This function cleans up gem object fields that are set up by
* drm_gem_private_object_init() and i915_gem_object_init().
* It's primarily intended as a helper for backends that need to
* clean up the gem object in separate steps.
*/
void __i915_gem_object_fini(struct drm_i915_gem_object *obj)
{
mutex_destroy(&obj->mm.get_page.lock);
mutex_destroy(&obj->mm.get_dma_page.lock);
dma_resv_fini(&obj->base._resv);
}
/**
* Mark up the object's coherency levels for a given cache_level
* @obj: #drm_i915_gem_object
* @cache_level: cache level
*/
void i915_gem_object_set_cache_coherency(struct drm_i915_gem_object *obj,
unsigned int cache_level)
{
obj->cache_level = cache_level;
if (cache_level != I915_CACHE_NONE)
obj->cache_coherent = (I915_BO_CACHE_COHERENT_FOR_READ |
I915_BO_CACHE_COHERENT_FOR_WRITE);
else if (HAS_LLC(to_i915(obj->base.dev)))
obj->cache_coherent = I915_BO_CACHE_COHERENT_FOR_READ;
else
obj->cache_coherent = 0;
obj->cache_dirty =
!(obj->cache_coherent & I915_BO_CACHE_COHERENT_FOR_WRITE);
}
bool i915_gem_object_can_bypass_llc(struct drm_i915_gem_object *obj)
{
struct drm_i915_private *i915 = to_i915(obj->base.dev);
/*
* This is purely from a security perspective, so we simply don't care
* about non-userspace objects being able to bypass the LLC.
*/
if (!(obj->flags & I915_BO_ALLOC_USER))
return false;
/*
* EHL and JSL add the 'Bypass LLC' MOCS entry, which should make it
* possible for userspace to bypass the GTT caching bits set by the
* kernel, as per the given object cache_level. This is troublesome
* since the heavy flush we apply when first gathering the pages is
* skipped if the kernel thinks the object is coherent with the GPU. As
* a result it might be possible to bypass the cache and read the
* contents of the page directly, which could be stale data. If it's
* just a case of userspace shooting themselves in the foot then so be
* it, but since i915 takes the stance of always zeroing memory before
* handing it to userspace, we need to prevent this.
*/
return IS_JSL_EHL(i915);
}
static void i915_gem_close_object(struct drm_gem_object *gem, struct drm_file *file)
{
struct drm_i915_gem_object *obj = to_intel_bo(gem);
struct drm_i915_file_private *fpriv = file->driver_priv;
struct i915_lut_handle bookmark = {};
struct i915_mmap_offset *mmo, *mn;
struct i915_lut_handle *lut, *ln;
LIST_HEAD(close);
spin_lock(&obj->lut_lock);
list_for_each_entry_safe(lut, ln, &obj->lut_list, obj_link) {
struct i915_gem_context *ctx = lut->ctx;
if (ctx && ctx->file_priv == fpriv) {
i915_gem_context_get(ctx);
list_move(&lut->obj_link, &close);
}
/* Break long locks, and carefully continue on from this spot */
if (&ln->obj_link != &obj->lut_list) {
list_add_tail(&bookmark.obj_link, &ln->obj_link);
if (cond_resched_lock(&obj->lut_lock))
list_safe_reset_next(&bookmark, ln, obj_link);
__list_del_entry(&bookmark.obj_link);
}
}
spin_unlock(&obj->lut_lock);
spin_lock(&obj->mmo.lock);
rbtree_postorder_for_each_entry_safe(mmo, mn, &obj->mmo.offsets, offset)
drm_vma_node_revoke(&mmo->vma_node, file);
spin_unlock(&obj->mmo.lock);
list_for_each_entry_safe(lut, ln, &close, obj_link) {
struct i915_gem_context *ctx = lut->ctx;
struct i915_vma *vma;
/*
* We allow the process to have multiple handles to the same
* vma, in the same fd namespace, by virtue of flink/open.
*/
mutex_lock(&ctx->lut_mutex);
vma = radix_tree_delete(&ctx->handles_vma, lut->handle);
if (vma) {
GEM_BUG_ON(vma->obj != obj);
GEM_BUG_ON(!atomic_read(&vma->open_count));
i915_vma_close(vma);
}
mutex_unlock(&ctx->lut_mutex);
i915_gem_context_put(lut->ctx);
i915_lut_handle_free(lut);
i915_gem_object_put(obj);
}
}
void __i915_gem_free_object_rcu(struct rcu_head *head)
{
struct drm_i915_gem_object *obj =
container_of(head, typeof(*obj), rcu);
struct drm_i915_private *i915 = to_i915(obj->base.dev);
i915_gem_object_free(obj);
GEM_BUG_ON(!atomic_read(&i915->mm.free_count));
atomic_dec(&i915->mm.free_count);
}
static void __i915_gem_object_free_mmaps(struct drm_i915_gem_object *obj)
{
/* Skip serialisation and waking the device if known to be not used. */
if (obj->userfault_count)
i915_gem_object_release_mmap_gtt(obj);
if (!RB_EMPTY_ROOT(&obj->mmo.offsets)) {
struct i915_mmap_offset *mmo, *mn;
i915_gem_object_release_mmap_offset(obj);
rbtree_postorder_for_each_entry_safe(mmo, mn,
&obj->mmo.offsets,
offset) {
drm_vma_offset_remove(obj->base.dev->vma_offset_manager,
&mmo->vma_node);
kfree(mmo);
}
obj->mmo.offsets = RB_ROOT;
}
}
/**
* __i915_gem_object_pages_fini - Clean up pages use of a gem object
* @obj: The gem object to clean up
*
* This function cleans up usage of the object mm.pages member. It
* is intended for backends that need to clean up a gem object in
* separate steps and needs to be called when the object is idle before
* the object's backing memory is freed.
*/
void __i915_gem_object_pages_fini(struct drm_i915_gem_object *obj)
{
if (!list_empty(&obj->vma.list)) {
struct i915_vma *vma;
/*
* Note that the vma keeps an object reference while
* it is active, so it *should* not sleep while we
* destroy it. Our debug code errs insits it *might*.
* For the moment, play along.
*/
spin_lock(&obj->vma.lock);
while ((vma = list_first_entry_or_null(&obj->vma.list,
struct i915_vma,
obj_link))) {
GEM_BUG_ON(vma->obj != obj);
spin_unlock(&obj->vma.lock);
__i915_vma_put(vma);
spin_lock(&obj->vma.lock);
}
spin_unlock(&obj->vma.lock);
}
__i915_gem_object_free_mmaps(obj);
atomic_set(&obj->mm.pages_pin_count, 0);
__i915_gem_object_put_pages(obj);
GEM_BUG_ON(i915_gem_object_has_pages(obj));
}
void __i915_gem_free_object(struct drm_i915_gem_object *obj)
{
trace_i915_gem_object_destroy(obj);
GEM_BUG_ON(!list_empty(&obj->lut_list));
bitmap_free(obj->bit_17);
if (obj->base.import_attach)
drm_prime_gem_destroy(&obj->base, NULL);
drm_gem_free_mmap_offset(&obj->base);
if (obj->ops->release)
obj->ops->release(obj);
if (obj->mm.n_placements > 1)
kfree(obj->mm.placements);
if (obj->shares_resv_from)
i915_vm_resv_put(obj->shares_resv_from);
__i915_gem_object_fini(obj);
}
static void __i915_gem_free_objects(struct drm_i915_private *i915,
struct llist_node *freed)
{
struct drm_i915_gem_object *obj, *on;
llist_for_each_entry_safe(obj, on, freed, freed) {
might_sleep();
if (obj->ops->delayed_free) {
obj->ops->delayed_free(obj);
continue;
}
__i915_gem_object_pages_fini(obj);
__i915_gem_free_object(obj);
/* But keep the pointer alive for RCU-protected lookups */
call_rcu(&obj->rcu, __i915_gem_free_object_rcu);
cond_resched();
}
}
void i915_gem_flush_free_objects(struct drm_i915_private *i915)
{
struct llist_node *freed = llist_del_all(&i915->mm.free_list);
if (unlikely(freed))
__i915_gem_free_objects(i915, freed);
}
static void __i915_gem_free_work(struct work_struct *work)
{
struct drm_i915_private *i915 =
container_of(work, struct drm_i915_private, mm.free_work);
i915_gem_flush_free_objects(i915);
}
static void i915_gem_free_object(struct drm_gem_object *gem_obj)
{
struct drm_i915_gem_object *obj = to_intel_bo(gem_obj);
struct drm_i915_private *i915 = to_i915(obj->base.dev);
GEM_BUG_ON(i915_gem_object_is_framebuffer(obj));
/*
* Before we free the object, make sure any pure RCU-only
* read-side critical sections are complete, e.g.
* i915_gem_busy_ioctl(). For the corresponding synchronized
* lookup see i915_gem_object_lookup_rcu().
*/
atomic_inc(&i915->mm.free_count);
/*
* This serializes freeing with the shrinker. Since the free
* is delayed, first by RCU then by the workqueue, we want the
* shrinker to be able to free pages of unreferenced objects,
* or else we may oom whilst there are plenty of deferred
* freed objects.
*/
i915_gem_object_make_unshrinkable(obj);
/*
* Since we require blocking on struct_mutex to unbind the freed
* object from the GPU before releasing resources back to the
* system, we can not do that directly from the RCU callback (which may
* be a softirq context), but must instead then defer that work onto a
* kthread. We use the RCU callback rather than move the freed object
* directly onto the work queue so that we can mix between using the
* worker and performing frees directly from subsequent allocations for
* crude but effective memory throttling.
*/
if (llist_add(&obj->freed, &i915->mm.free_list))
queue_work(i915->wq, &i915->mm.free_work);
}
void __i915_gem_object_flush_frontbuffer(struct drm_i915_gem_object *obj,
enum fb_op_origin origin)
{
struct intel_frontbuffer *front;
front = __intel_frontbuffer_get(obj);
if (front) {
intel_frontbuffer_flush(front, origin);
intel_frontbuffer_put(front);
}
}
void __i915_gem_object_invalidate_frontbuffer(struct drm_i915_gem_object *obj,
enum fb_op_origin origin)
{
struct intel_frontbuffer *front;
front = __intel_frontbuffer_get(obj);
if (front) {
intel_frontbuffer_invalidate(front, origin);
intel_frontbuffer_put(front);
}
}
static void
i915_gem_object_read_from_page_kmap(struct drm_i915_gem_object *obj, u64 offset, void *dst, int size)
{
void *src_map;
void *src_ptr;
src_map = kmap_atomic(i915_gem_object_get_page(obj, offset >> PAGE_SHIFT));
src_ptr = src_map + offset_in_page(offset);
if (!(obj->cache_coherent & I915_BO_CACHE_COHERENT_FOR_READ))
drm_clflush_virt_range(src_ptr, size);
memcpy(dst, src_ptr, size);
kunmap_atomic(src_map);
}
static void
i915_gem_object_read_from_page_iomap(struct drm_i915_gem_object *obj, u64 offset, void *dst, int size)
{
void __iomem *src_map;
void __iomem *src_ptr;
dma_addr_t dma = i915_gem_object_get_dma_address(obj, offset >> PAGE_SHIFT);
src_map = io_mapping_map_wc(&obj->mm.region->iomap,
dma - obj->mm.region->region.start,
PAGE_SIZE);
src_ptr = src_map + offset_in_page(offset);
if (!i915_memcpy_from_wc(dst, (void __force *)src_ptr, size))
memcpy_fromio(dst, src_ptr, size);
io_mapping_unmap(src_map);
}
/**
* i915_gem_object_read_from_page - read data from the page of a GEM object
* @obj: GEM object to read from
* @offset: offset within the object
* @dst: buffer to store the read data
* @size: size to read
*
* Reads data from @obj at the specified offset. The requested region to read
* from can't cross a page boundary. The caller must ensure that @obj pages
* are pinned and that @obj is synced wrt. any related writes.
*
* Returns 0 on success or -ENODEV if the type of @obj's backing store is
* unsupported.
*/
int i915_gem_object_read_from_page(struct drm_i915_gem_object *obj, u64 offset, void *dst, int size)
{
GEM_BUG_ON(offset >= obj->base.size);
GEM_BUG_ON(offset_in_page(offset) > PAGE_SIZE - size);
GEM_BUG_ON(!i915_gem_object_has_pinned_pages(obj));
if (i915_gem_object_has_struct_page(obj))
i915_gem_object_read_from_page_kmap(obj, offset, dst, size);
else if (i915_gem_object_has_iomem(obj))
i915_gem_object_read_from_page_iomap(obj, offset, dst, size);
else
return -ENODEV;
return 0;
}
/**
* i915_gem_object_evictable - Whether object is likely evictable after unbind.
* @obj: The object to check
*
* This function checks whether the object is likely unvictable after unbind.
* If the object is not locked when checking, the result is only advisory.
* If the object is locked when checking, and the function returns true,
* then an eviction should indeed be possible. But since unlocked vma
* unpinning and unbinding is currently possible, the object can actually
* become evictable even if this function returns false.
*
* Return: true if the object may be evictable. False otherwise.
*/
bool i915_gem_object_evictable(struct drm_i915_gem_object *obj)
{
struct i915_vma *vma;
int pin_count = atomic_read(&obj->mm.pages_pin_count);
if (!pin_count)
return true;
spin_lock(&obj->vma.lock);
list_for_each_entry(vma, &obj->vma.list, obj_link) {
if (i915_vma_is_pinned(vma)) {
spin_unlock(&obj->vma.lock);
return false;
}
if (atomic_read(&vma->pages_count))
pin_count--;
}
spin_unlock(&obj->vma.lock);
GEM_WARN_ON(pin_count < 0);
return pin_count == 0;
}
/**
* i915_gem_object_migratable - Whether the object is migratable out of the
* current region.
* @obj: Pointer to the object.
*
* Return: Whether the object is allowed to be resident in other
* regions than the current while pages are present.
*/
bool i915_gem_object_migratable(struct drm_i915_gem_object *obj)
{
struct intel_memory_region *mr = READ_ONCE(obj->mm.region);
if (!mr)
return false;
return obj->mm.n_placements > 1;
}
/**
* i915_gem_object_has_struct_page - Whether the object is page-backed
* @obj: The object to query.
*
* This function should only be called while the object is locked or pinned,
* otherwise the page backing may change under the caller.
*
* Return: True if page-backed, false otherwise.
*/
bool i915_gem_object_has_struct_page(const struct drm_i915_gem_object *obj)
{
#ifdef CONFIG_LOCKDEP
if (IS_DGFX(to_i915(obj->base.dev)) &&
i915_gem_object_evictable((void __force *)obj))
assert_object_held_shared(obj);
#endif
return obj->mem_flags & I915_BO_FLAG_STRUCT_PAGE;
}
/**
* i915_gem_object_has_iomem - Whether the object is iomem-backed
* @obj: The object to query.
*
* This function should only be called while the object is locked or pinned,
* otherwise the iomem backing may change under the caller.
*
* Return: True if iomem-backed, false otherwise.
*/
bool i915_gem_object_has_iomem(const struct drm_i915_gem_object *obj)
{
#ifdef CONFIG_LOCKDEP
if (IS_DGFX(to_i915(obj->base.dev)) &&
i915_gem_object_evictable((void __force *)obj))
assert_object_held_shared(obj);
#endif
return obj->mem_flags & I915_BO_FLAG_IOMEM;
}
/**
* i915_gem_object_can_migrate - Whether an object likely can be migrated
*
* @obj: The object to migrate
* @id: The region intended to migrate to
*
* Check whether the object backend supports migration to the
* given region. Note that pinning may affect the ability to migrate as
* returned by this function.
*
* This function is primarily intended as a helper for checking the
* possibility to migrate objects and might be slightly less permissive
* than i915_gem_object_migrate() when it comes to objects with the
* I915_BO_ALLOC_USER flag set.
*
* Return: true if migration is possible, false otherwise.
*/
bool i915_gem_object_can_migrate(struct drm_i915_gem_object *obj,
enum intel_region_id id)
{
struct drm_i915_private *i915 = to_i915(obj->base.dev);
unsigned int num_allowed = obj->mm.n_placements;
struct intel_memory_region *mr;
unsigned int i;
GEM_BUG_ON(id >= INTEL_REGION_UNKNOWN);
GEM_BUG_ON(obj->mm.madv != I915_MADV_WILLNEED);
mr = i915->mm.regions[id];
if (!mr)
return false;
if (obj->mm.region == mr)
return true;
if (!i915_gem_object_evictable(obj))
return false;
if (!obj->ops->migrate)
return false;
if (!(obj->flags & I915_BO_ALLOC_USER))
return true;
if (num_allowed == 0)
return false;
for (i = 0; i < num_allowed; ++i) {
if (mr == obj->mm.placements[i])
return true;
}
return false;
}
/**
* i915_gem_object_migrate - Migrate an object to the desired region id
* @obj: The object to migrate.
* @ww: An optional struct i915_gem_ww_ctx. If NULL, the backend may
* not be successful in evicting other objects to make room for this object.
* @id: The region id to migrate to.
*
* Attempt to migrate the object to the desired memory region. The
* object backend must support migration and the object may not be
* pinned, (explicitly pinned pages or pinned vmas). The object must
* be locked.
* On successful completion, the object will have pages pointing to
* memory in the new region, but an async migration task may not have
* completed yet, and to accomplish that, i915_gem_object_wait_migration()
* must be called.
*
* Note: the @ww parameter is not used yet, but included to make sure
* callers put some effort into obtaining a valid ww ctx if one is
* available.
*
* Return: 0 on success. Negative error code on failure. In particular may
* return -ENXIO on lack of region space, -EDEADLK for deadlock avoidance
* if @ww is set, -EINTR or -ERESTARTSYS if signal pending, and
* -EBUSY if the object is pinned.
*/
int i915_gem_object_migrate(struct drm_i915_gem_object *obj,
struct i915_gem_ww_ctx *ww,
enum intel_region_id id)
{
struct drm_i915_private *i915 = to_i915(obj->base.dev);
struct intel_memory_region *mr;
GEM_BUG_ON(id >= INTEL_REGION_UNKNOWN);
GEM_BUG_ON(obj->mm.madv != I915_MADV_WILLNEED);
assert_object_held(obj);
mr = i915->mm.regions[id];
GEM_BUG_ON(!mr);
if (!i915_gem_object_can_migrate(obj, id))
return -EINVAL;
if (!obj->ops->migrate) {
if (GEM_WARN_ON(obj->mm.region != mr))
return -EINVAL;
return 0;
}
return obj->ops->migrate(obj, mr);
}
/**
* i915_gem_object_placement_possible - Check whether the object can be
* placed at certain memory type
* @obj: Pointer to the object
* @type: The memory type to check
*
* Return: True if the object can be placed in @type. False otherwise.
*/
bool i915_gem_object_placement_possible(struct drm_i915_gem_object *obj,
enum intel_memory_type type)
{
unsigned int i;
if (!obj->mm.n_placements) {
switch (type) {
case INTEL_MEMORY_LOCAL:
return i915_gem_object_has_iomem(obj);
case INTEL_MEMORY_SYSTEM:
return i915_gem_object_has_pages(obj);
default:
/* Ignore stolen for now */
GEM_BUG_ON(1);
return false;
}
}
for (i = 0; i < obj->mm.n_placements; i++) {
if (obj->mm.placements[i]->type == type)
return true;
}
return false;
}
void i915_gem_init__objects(struct drm_i915_private *i915)
{
INIT_WORK(&i915->mm.free_work, __i915_gem_free_work);
}
void i915_objects_module_exit(void)
{
kmem_cache_destroy(slab_objects);
}
int __init i915_objects_module_init(void)
{
slab_objects = KMEM_CACHE(drm_i915_gem_object, SLAB_HWCACHE_ALIGN);
if (!slab_objects)
return -ENOMEM;
return 0;
}
static const struct drm_gem_object_funcs i915_gem_object_funcs = {
.free = i915_gem_free_object,
.close = i915_gem_close_object,
.export = i915_gem_prime_export,
};
#if IS_ENABLED(CONFIG_DRM_I915_SELFTEST)
#include "selftests/huge_gem_object.c"
#include "selftests/huge_pages.c"
#include "selftests/i915_gem_migrate.c"
#include "selftests/i915_gem_object.c"
#include "selftests/i915_gem_coherency.c"
#endif