linuxdebug/drivers/gpu/drm/i915/gt/intel_gtt.h

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2024-07-16 15:50:57 +02:00
/* SPDX-License-Identifier: MIT */
/*
* Copyright © 2020 Intel Corporation
*
* Please try to maintain the following order within this file unless it makes
* sense to do otherwise. From top to bottom:
* 1. typedefs
* 2. #defines, and macros
* 3. structure definitions
* 4. function prototypes
*
* Within each section, please try to order by generation in ascending order,
* from top to bottom (ie. gen6 on the top, gen8 on the bottom).
*/
#ifndef __INTEL_GTT_H__
#define __INTEL_GTT_H__
#include <linux/io-mapping.h>
#include <linux/kref.h>
#include <linux/mm.h>
#include <linux/pagevec.h>
#include <linux/scatterlist.h>
#include <linux/workqueue.h>
#include <drm/drm_mm.h>
#include "gt/intel_reset.h"
#include "i915_selftest.h"
#include "i915_vma_resource.h"
#include "i915_vma_types.h"
#include "i915_params.h"
#include "intel_memory_region.h"
#define I915_GFP_ALLOW_FAIL (GFP_KERNEL | __GFP_RETRY_MAYFAIL | __GFP_NOWARN)
#if IS_ENABLED(CONFIG_DRM_I915_TRACE_GTT)
#define DBG(...) trace_printk(__VA_ARGS__)
#else
#define DBG(...)
#endif
#define NALLOC 3 /* 1 normal, 1 for concurrent threads, 1 for preallocation */
#define I915_GTT_PAGE_SIZE_4K BIT_ULL(12)
#define I915_GTT_PAGE_SIZE_64K BIT_ULL(16)
#define I915_GTT_PAGE_SIZE_2M BIT_ULL(21)
#define I915_GTT_PAGE_SIZE I915_GTT_PAGE_SIZE_4K
#define I915_GTT_MAX_PAGE_SIZE I915_GTT_PAGE_SIZE_2M
#define I915_GTT_PAGE_MASK -I915_GTT_PAGE_SIZE
#define I915_GTT_MIN_ALIGNMENT I915_GTT_PAGE_SIZE
#define I915_FENCE_REG_NONE -1
#define I915_MAX_NUM_FENCES 32
/* 32 fences + sign bit for FENCE_REG_NONE */
#define I915_MAX_NUM_FENCE_BITS 6
typedef u32 gen6_pte_t;
typedef u64 gen8_pte_t;
#define ggtt_total_entries(ggtt) ((ggtt)->vm.total >> PAGE_SHIFT)
#define I915_PTES(pte_len) ((unsigned int)(PAGE_SIZE / (pte_len)))
#define I915_PTE_MASK(pte_len) (I915_PTES(pte_len) - 1)
#define I915_PDES 512
#define I915_PDE_MASK (I915_PDES - 1)
/* gen6-hsw has bit 11-4 for physical addr bit 39-32 */
#define GEN6_GTT_ADDR_ENCODE(addr) ((addr) | (((addr) >> 28) & 0xff0))
#define GEN6_PTE_ADDR_ENCODE(addr) GEN6_GTT_ADDR_ENCODE(addr)
#define GEN6_PDE_ADDR_ENCODE(addr) GEN6_GTT_ADDR_ENCODE(addr)
#define GEN6_PTE_CACHE_LLC (2 << 1)
#define GEN6_PTE_UNCACHED (1 << 1)
#define GEN6_PTE_VALID REG_BIT(0)
#define GEN6_PTES I915_PTES(sizeof(gen6_pte_t))
#define GEN6_PD_SIZE (I915_PDES * PAGE_SIZE)
#define GEN6_PD_ALIGN (PAGE_SIZE * 16)
#define GEN6_PDE_SHIFT 22
#define GEN6_PDE_VALID REG_BIT(0)
#define NUM_PTE(pde_shift) (1 << (pde_shift - PAGE_SHIFT))
#define GEN7_PTE_CACHE_L3_LLC (3 << 1)
#define BYT_PTE_SNOOPED_BY_CPU_CACHES REG_BIT(2)
#define BYT_PTE_WRITEABLE REG_BIT(1)
#define GEN12_PPGTT_PTE_LM BIT_ULL(11)
#define GEN12_GGTT_PTE_LM BIT_ULL(1)
#define GEN12_PDE_64K BIT(6)
/*
* Cacheability Control is a 4-bit value. The low three bits are stored in bits
* 3:1 of the PTE, while the fourth bit is stored in bit 11 of the PTE.
*/
#define HSW_CACHEABILITY_CONTROL(bits) ((((bits) & 0x7) << 1) | \
(((bits) & 0x8) << (11 - 3)))
#define HSW_WB_LLC_AGE3 HSW_CACHEABILITY_CONTROL(0x2)
#define HSW_WB_LLC_AGE0 HSW_CACHEABILITY_CONTROL(0x3)
#define HSW_WB_ELLC_LLC_AGE3 HSW_CACHEABILITY_CONTROL(0x8)
#define HSW_WB_ELLC_LLC_AGE0 HSW_CACHEABILITY_CONTROL(0xb)
#define HSW_WT_ELLC_LLC_AGE3 HSW_CACHEABILITY_CONTROL(0x7)
#define HSW_WT_ELLC_LLC_AGE0 HSW_CACHEABILITY_CONTROL(0x6)
#define HSW_PTE_UNCACHED (0)
#define HSW_GTT_ADDR_ENCODE(addr) ((addr) | (((addr) >> 28) & 0x7f0))
#define HSW_PTE_ADDR_ENCODE(addr) HSW_GTT_ADDR_ENCODE(addr)
/*
* GEN8 32b style address is defined as a 3 level page table:
* 31:30 | 29:21 | 20:12 | 11:0
* PDPE | PDE | PTE | offset
* The difference as compared to normal x86 3 level page table is the PDPEs are
* programmed via register.
*
* GEN8 48b style address is defined as a 4 level page table:
* 47:39 | 38:30 | 29:21 | 20:12 | 11:0
* PML4E | PDPE | PDE | PTE | offset
*/
#define GEN8_3LVL_PDPES 4
#define PPAT_UNCACHED (_PAGE_PWT | _PAGE_PCD)
#define PPAT_CACHED_PDE 0 /* WB LLC */
#define PPAT_CACHED _PAGE_PAT /* WB LLCeLLC */
#define PPAT_DISPLAY_ELLC _PAGE_PCD /* WT eLLC */
#define CHV_PPAT_SNOOP REG_BIT(6)
#define GEN8_PPAT_AGE(x) ((x)<<4)
#define GEN8_PPAT_LLCeLLC (3<<2)
#define GEN8_PPAT_LLCELLC (2<<2)
#define GEN8_PPAT_LLC (1<<2)
#define GEN8_PPAT_WB (3<<0)
#define GEN8_PPAT_WT (2<<0)
#define GEN8_PPAT_WC (1<<0)
#define GEN8_PPAT_UC (0<<0)
#define GEN8_PPAT_ELLC_OVERRIDE (0<<2)
#define GEN8_PPAT(i, x) ((u64)(x) << ((i) * 8))
#define GEN8_PAGE_PRESENT BIT_ULL(0)
#define GEN8_PAGE_RW BIT_ULL(1)
#define GEN8_PDE_IPS_64K BIT(11)
#define GEN8_PDE_PS_2M BIT(7)
enum i915_cache_level;
struct drm_i915_gem_object;
struct i915_fence_reg;
struct i915_vma;
struct intel_gt;
#define for_each_sgt_daddr(__dp, __iter, __sgt) \
__for_each_sgt_daddr(__dp, __iter, __sgt, I915_GTT_PAGE_SIZE)
struct i915_page_table {
struct drm_i915_gem_object *base;
union {
atomic_t used;
struct i915_page_table *stash;
};
bool is_compact;
};
struct i915_page_directory {
struct i915_page_table pt;
spinlock_t lock;
void **entry;
};
#define __px_choose_expr(x, type, expr, other) \
__builtin_choose_expr( \
__builtin_types_compatible_p(typeof(x), type) || \
__builtin_types_compatible_p(typeof(x), const type), \
({ type __x = (type)(x); expr; }), \
other)
#define px_base(px) \
__px_choose_expr(px, struct drm_i915_gem_object *, __x, \
__px_choose_expr(px, struct i915_page_table *, __x->base, \
__px_choose_expr(px, struct i915_page_directory *, __x->pt.base, \
(void)0)))
struct page *__px_page(struct drm_i915_gem_object *p);
dma_addr_t __px_dma(struct drm_i915_gem_object *p);
#define px_dma(px) (__px_dma(px_base(px)))
void *__px_vaddr(struct drm_i915_gem_object *p);
#define px_vaddr(px) (__px_vaddr(px_base(px)))
#define px_pt(px) \
__px_choose_expr(px, struct i915_page_table *, __x, \
__px_choose_expr(px, struct i915_page_directory *, &__x->pt, \
(void)0))
#define px_used(px) (&px_pt(px)->used)
struct i915_vm_pt_stash {
/* preallocated chains of page tables/directories */
struct i915_page_table *pt[2];
/*
* Optionally override the alignment/size of the physical page that
* contains each PT. If not set defaults back to the usual
* I915_GTT_PAGE_SIZE_4K. This does not influence the other paging
* structures. MUST be a power-of-two. ONLY applicable on discrete
* platforms.
*/
int pt_sz;
};
struct i915_vma_ops {
/* Map an object into an address space with the given cache flags. */
void (*bind_vma)(struct i915_address_space *vm,
struct i915_vm_pt_stash *stash,
struct i915_vma_resource *vma_res,
enum i915_cache_level cache_level,
u32 flags);
/*
* Unmap an object from an address space. This usually consists of
* setting the valid PTE entries to a reserved scratch page.
*/
void (*unbind_vma)(struct i915_address_space *vm,
struct i915_vma_resource *vma_res);
};
struct i915_address_space {
struct kref ref;
struct work_struct release_work;
struct drm_mm mm;
struct intel_gt *gt;
struct drm_i915_private *i915;
struct device *dma;
u64 total; /* size addr space maps (ex. 2GB for ggtt) */
u64 reserved; /* size addr space reserved */
u64 min_alignment[INTEL_MEMORY_STOLEN_LOCAL + 1];
unsigned int bind_async_flags;
struct mutex mutex; /* protects vma and our lists */
struct kref resv_ref; /* kref to keep the reservation lock alive. */
struct dma_resv _resv; /* reservation lock for all pd objects, and buffer pool */
#define VM_CLASS_GGTT 0
#define VM_CLASS_PPGTT 1
#define VM_CLASS_DPT 2
struct drm_i915_gem_object *scratch[4];
/**
* List of vma currently bound.
*/
struct list_head bound_list;
/**
* List of vmas not yet bound or evicted.
*/
struct list_head unbound_list;
/* Global GTT */
bool is_ggtt:1;
/* Display page table */
bool is_dpt:1;
/* Some systems support read-only mappings for GGTT and/or PPGTT */
bool has_read_only:1;
/* Skip pte rewrite on unbind for suspend. Protected by @mutex */
bool skip_pte_rewrite:1;
u8 top;
u8 pd_shift;
u8 scratch_order;
/* Flags used when creating page-table objects for this vm */
unsigned long lmem_pt_obj_flags;
/* Interval tree for pending unbind vma resources */
struct rb_root_cached pending_unbind;
struct drm_i915_gem_object *
(*alloc_pt_dma)(struct i915_address_space *vm, int sz);
struct drm_i915_gem_object *
(*alloc_scratch_dma)(struct i915_address_space *vm, int sz);
u64 (*pte_encode)(dma_addr_t addr,
enum i915_cache_level level,
u32 flags); /* Create a valid PTE */
#define PTE_READ_ONLY BIT(0)
#define PTE_LM BIT(1)
void (*allocate_va_range)(struct i915_address_space *vm,
struct i915_vm_pt_stash *stash,
u64 start, u64 length);
void (*clear_range)(struct i915_address_space *vm,
u64 start, u64 length);
void (*insert_page)(struct i915_address_space *vm,
dma_addr_t addr,
u64 offset,
enum i915_cache_level cache_level,
u32 flags);
void (*insert_entries)(struct i915_address_space *vm,
struct i915_vma_resource *vma_res,
enum i915_cache_level cache_level,
u32 flags);
void (*raw_insert_page)(struct i915_address_space *vm,
dma_addr_t addr,
u64 offset,
enum i915_cache_level cache_level,
u32 flags);
void (*raw_insert_entries)(struct i915_address_space *vm,
struct i915_vma_resource *vma_res,
enum i915_cache_level cache_level,
u32 flags);
void (*cleanup)(struct i915_address_space *vm);
void (*foreach)(struct i915_address_space *vm,
u64 start, u64 length,
void (*fn)(struct i915_address_space *vm,
struct i915_page_table *pt,
void *data),
void *data);
struct i915_vma_ops vma_ops;
I915_SELFTEST_DECLARE(struct fault_attr fault_attr);
I915_SELFTEST_DECLARE(bool scrub_64K);
};
/*
* The Graphics Translation Table is the way in which GEN hardware translates a
* Graphics Virtual Address into a Physical Address. In addition to the normal
* collateral associated with any va->pa translations GEN hardware also has a
* portion of the GTT which can be mapped by the CPU and remain both coherent
* and correct (in cases like swizzling). That region is referred to as GMADR in
* the spec.
*/
struct i915_ggtt {
struct i915_address_space vm;
struct io_mapping iomap; /* Mapping to our CPU mappable region */
struct resource gmadr; /* GMADR resource */
resource_size_t mappable_end; /* End offset that we can CPU map */
/** "Graphics Stolen Memory" holds the global PTEs */
void __iomem *gsm;
void (*invalidate)(struct i915_ggtt *ggtt);
/** PPGTT used for aliasing the PPGTT with the GTT */
struct i915_ppgtt *alias;
bool do_idle_maps;
/**
* @pte_lost: Are ptes lost on resume?
*
* Whether the system was recently restored from hibernate and
* thus may have lost pte content.
*/
bool pte_lost;
/**
* @probed_pte: Probed pte value on suspend. Re-checked on resume.
*/
u64 probed_pte;
int mtrr;
/** Bit 6 swizzling required for X tiling */
u32 bit_6_swizzle_x;
/** Bit 6 swizzling required for Y tiling */
u32 bit_6_swizzle_y;
u32 pin_bias;
unsigned int num_fences;
struct i915_fence_reg *fence_regs;
struct list_head fence_list;
/**
* List of all objects in gtt_space, currently mmaped by userspace.
* All objects within this list must also be on bound_list.
*/
struct list_head userfault_list;
struct mutex error_mutex;
struct drm_mm_node error_capture;
struct drm_mm_node uc_fw;
};
struct i915_ppgtt {
struct i915_address_space vm;
struct i915_page_directory *pd;
};
#define i915_is_ggtt(vm) ((vm)->is_ggtt)
#define i915_is_dpt(vm) ((vm)->is_dpt)
#define i915_is_ggtt_or_dpt(vm) (i915_is_ggtt(vm) || i915_is_dpt(vm))
bool intel_vm_no_concurrent_access_wa(struct drm_i915_private *i915);
int __must_check
i915_vm_lock_objects(struct i915_address_space *vm, struct i915_gem_ww_ctx *ww);
static inline bool
i915_vm_is_4lvl(const struct i915_address_space *vm)
{
return (vm->total - 1) >> 32;
}
static inline bool
i915_vm_has_scratch_64K(struct i915_address_space *vm)
{
return vm->scratch_order == get_order(I915_GTT_PAGE_SIZE_64K);
}
static inline u64 i915_vm_min_alignment(struct i915_address_space *vm,
enum intel_memory_type type)
{
/* avoid INTEL_MEMORY_MOCK overflow */
if ((int)type >= ARRAY_SIZE(vm->min_alignment))
type = INTEL_MEMORY_SYSTEM;
return vm->min_alignment[type];
}
static inline u64 i915_vm_obj_min_alignment(struct i915_address_space *vm,
struct drm_i915_gem_object *obj)
{
struct intel_memory_region *mr = READ_ONCE(obj->mm.region);
enum intel_memory_type type = mr ? mr->type : INTEL_MEMORY_SYSTEM;
return i915_vm_min_alignment(vm, type);
}
static inline bool
i915_vm_has_cache_coloring(struct i915_address_space *vm)
{
return i915_is_ggtt(vm) && vm->mm.color_adjust;
}
static inline struct i915_ggtt *
i915_vm_to_ggtt(struct i915_address_space *vm)
{
BUILD_BUG_ON(offsetof(struct i915_ggtt, vm));
GEM_BUG_ON(!i915_is_ggtt(vm));
return container_of(vm, struct i915_ggtt, vm);
}
static inline struct i915_ppgtt *
i915_vm_to_ppgtt(struct i915_address_space *vm)
{
BUILD_BUG_ON(offsetof(struct i915_ppgtt, vm));
GEM_BUG_ON(i915_is_ggtt_or_dpt(vm));
return container_of(vm, struct i915_ppgtt, vm);
}
static inline struct i915_address_space *
i915_vm_get(struct i915_address_space *vm)
{
kref_get(&vm->ref);
return vm;
}
static inline struct i915_address_space *
i915_vm_tryget(struct i915_address_space *vm)
{
return kref_get_unless_zero(&vm->ref) ? vm : NULL;
}
static inline void assert_vm_alive(struct i915_address_space *vm)
{
GEM_BUG_ON(!kref_read(&vm->ref));
}
/**
* i915_vm_resv_get - Obtain a reference on the vm's reservation lock
* @vm: The vm whose reservation lock we want to share.
*
* Return: A pointer to the vm's reservation lock.
*/
static inline struct dma_resv *i915_vm_resv_get(struct i915_address_space *vm)
{
kref_get(&vm->resv_ref);
return &vm->_resv;
}
void i915_vm_release(struct kref *kref);
void i915_vm_resv_release(struct kref *kref);
static inline void i915_vm_put(struct i915_address_space *vm)
{
kref_put(&vm->ref, i915_vm_release);
}
/**
* i915_vm_resv_put - Release a reference on the vm's reservation lock
* @resv: Pointer to a reservation lock obtained from i915_vm_resv_get()
*/
static inline void i915_vm_resv_put(struct i915_address_space *vm)
{
kref_put(&vm->resv_ref, i915_vm_resv_release);
}
void i915_address_space_init(struct i915_address_space *vm, int subclass);
void i915_address_space_fini(struct i915_address_space *vm);
static inline u32 i915_pte_index(u64 address, unsigned int pde_shift)
{
const u32 mask = NUM_PTE(pde_shift) - 1;
return (address >> PAGE_SHIFT) & mask;
}
/*
* Helper to counts the number of PTEs within the given length. This count
* does not cross a page table boundary, so the max value would be
* GEN6_PTES for GEN6, and GEN8_PTES for GEN8.
*/
static inline u32 i915_pte_count(u64 addr, u64 length, unsigned int pde_shift)
{
const u64 mask = ~((1ULL << pde_shift) - 1);
u64 end;
GEM_BUG_ON(length == 0);
GEM_BUG_ON(offset_in_page(addr | length));
end = addr + length;
if ((addr & mask) != (end & mask))
return NUM_PTE(pde_shift) - i915_pte_index(addr, pde_shift);
return i915_pte_index(end, pde_shift) - i915_pte_index(addr, pde_shift);
}
static inline u32 i915_pde_index(u64 addr, u32 shift)
{
return (addr >> shift) & I915_PDE_MASK;
}
static inline struct i915_page_table *
i915_pt_entry(const struct i915_page_directory * const pd,
const unsigned short n)
{
return pd->entry[n];
}
static inline struct i915_page_directory *
i915_pd_entry(const struct i915_page_directory * const pdp,
const unsigned short n)
{
return pdp->entry[n];
}
static inline dma_addr_t
i915_page_dir_dma_addr(const struct i915_ppgtt *ppgtt, const unsigned int n)
{
struct i915_page_table *pt = ppgtt->pd->entry[n];
return __px_dma(pt ? px_base(pt) : ppgtt->vm.scratch[ppgtt->vm.top]);
}
void ppgtt_init(struct i915_ppgtt *ppgtt, struct intel_gt *gt,
unsigned long lmem_pt_obj_flags);
void intel_ggtt_bind_vma(struct i915_address_space *vm,
struct i915_vm_pt_stash *stash,
struct i915_vma_resource *vma_res,
enum i915_cache_level cache_level,
u32 flags);
void intel_ggtt_unbind_vma(struct i915_address_space *vm,
struct i915_vma_resource *vma_res);
int i915_ggtt_probe_hw(struct drm_i915_private *i915);
int i915_ggtt_init_hw(struct drm_i915_private *i915);
int i915_ggtt_enable_hw(struct drm_i915_private *i915);
void i915_ggtt_enable_guc(struct i915_ggtt *ggtt);
void i915_ggtt_disable_guc(struct i915_ggtt *ggtt);
int i915_init_ggtt(struct drm_i915_private *i915);
void i915_ggtt_driver_release(struct drm_i915_private *i915);
void i915_ggtt_driver_late_release(struct drm_i915_private *i915);
static inline bool i915_ggtt_has_aperture(const struct i915_ggtt *ggtt)
{
return ggtt->mappable_end > 0;
}
int i915_ppgtt_init_hw(struct intel_gt *gt);
struct i915_ppgtt *i915_ppgtt_create(struct intel_gt *gt,
unsigned long lmem_pt_obj_flags);
void i915_ggtt_suspend_vm(struct i915_address_space *vm);
bool i915_ggtt_resume_vm(struct i915_address_space *vm);
void i915_ggtt_suspend(struct i915_ggtt *gtt);
void i915_ggtt_resume(struct i915_ggtt *ggtt);
/**
* i915_ggtt_mark_pte_lost - Mark ggtt ptes as lost or clear such a marking
* @i915 The device private.
* @val whether the ptes should be marked as lost.
*
* In some cases pte content is retained across suspend, but typically lost
* across hibernate. Typically they should be marked as lost on
* hibernation restore and such marking cleared on suspend.
*/
void i915_ggtt_mark_pte_lost(struct drm_i915_private *i915, bool val);
void
fill_page_dma(struct drm_i915_gem_object *p, const u64 val, unsigned int count);
#define fill_px(px, v) fill_page_dma(px_base(px), (v), PAGE_SIZE / sizeof(u64))
#define fill32_px(px, v) do { \
u64 v__ = lower_32_bits(v); \
fill_px((px), v__ << 32 | v__); \
} while (0)
int setup_scratch_page(struct i915_address_space *vm);
void free_scratch(struct i915_address_space *vm);
struct drm_i915_gem_object *alloc_pt_dma(struct i915_address_space *vm, int sz);
struct drm_i915_gem_object *alloc_pt_lmem(struct i915_address_space *vm, int sz);
struct i915_page_table *alloc_pt(struct i915_address_space *vm, int sz);
struct i915_page_directory *alloc_pd(struct i915_address_space *vm);
struct i915_page_directory *__alloc_pd(int npde);
int map_pt_dma(struct i915_address_space *vm, struct drm_i915_gem_object *obj);
int map_pt_dma_locked(struct i915_address_space *vm, struct drm_i915_gem_object *obj);
void free_px(struct i915_address_space *vm,
struct i915_page_table *pt, int lvl);
#define free_pt(vm, px) free_px(vm, px, 0)
#define free_pd(vm, px) free_px(vm, px_pt(px), 1)
void
__set_pd_entry(struct i915_page_directory * const pd,
const unsigned short idx,
struct i915_page_table *pt,
u64 (*encode)(const dma_addr_t, const enum i915_cache_level));
#define set_pd_entry(pd, idx, to) \
__set_pd_entry((pd), (idx), px_pt(to), gen8_pde_encode)
void
clear_pd_entry(struct i915_page_directory * const pd,
const unsigned short idx,
const struct drm_i915_gem_object * const scratch);
bool
release_pd_entry(struct i915_page_directory * const pd,
const unsigned short idx,
struct i915_page_table * const pt,
const struct drm_i915_gem_object * const scratch);
void gen6_ggtt_invalidate(struct i915_ggtt *ggtt);
void ppgtt_bind_vma(struct i915_address_space *vm,
struct i915_vm_pt_stash *stash,
struct i915_vma_resource *vma_res,
enum i915_cache_level cache_level,
u32 flags);
void ppgtt_unbind_vma(struct i915_address_space *vm,
struct i915_vma_resource *vma_res);
void gtt_write_workarounds(struct intel_gt *gt);
void setup_private_pat(struct intel_uncore *uncore);
int i915_vm_alloc_pt_stash(struct i915_address_space *vm,
struct i915_vm_pt_stash *stash,
u64 size);
int i915_vm_map_pt_stash(struct i915_address_space *vm,
struct i915_vm_pt_stash *stash);
void i915_vm_free_pt_stash(struct i915_address_space *vm,
struct i915_vm_pt_stash *stash);
struct i915_vma *
__vm_create_scratch_for_read(struct i915_address_space *vm, unsigned long size);
struct i915_vma *
__vm_create_scratch_for_read_pinned(struct i915_address_space *vm, unsigned long size);
static inline struct sgt_dma {
struct scatterlist *sg;
dma_addr_t dma, max;
} sgt_dma(struct i915_vma_resource *vma_res) {
struct scatterlist *sg = vma_res->bi.pages->sgl;
dma_addr_t addr = sg_dma_address(sg);
return (struct sgt_dma){ sg, addr, addr + sg_dma_len(sg) };
}
#endif