--- /dev/null
+ // SPDX-License-Identifier: MIT
+ /*
+  * Copyright Â© 2020 Intel Corporation
+  */
+ 
+ #include <linux/log2.h>
+ 
+ #include "gen6_ppgtt.h"
+ #include "i915_scatterlist.h"
+ #include "i915_trace.h"
+ #include "i915_vgpu.h"
+ #include "intel_gt.h"
+ 
+ /* Write pde (index) from the page directory @pd to the page table @pt */
+ static inline void gen6_write_pde(const struct gen6_ppgtt *ppgtt,
+                                 const unsigned int pde,
+                                 const struct i915_page_table *pt)
+ {
+       /* Caller needs to make sure the write completes if necessary */
+       iowrite32(GEN6_PDE_ADDR_ENCODE(px_dma(pt)) | GEN6_PDE_VALID,
+                 ppgtt->pd_addr + pde);
+ }
+ 
+ void gen7_ppgtt_enable(struct intel_gt *gt)
+ {
+       struct drm_i915_private *i915 = gt->i915;
+       struct intel_uncore *uncore = gt->uncore;
+       struct intel_engine_cs *engine;
+       enum intel_engine_id id;
+       u32 ecochk;
+ 
+       intel_uncore_rmw(uncore, GAC_ECO_BITS, 0, ECOBITS_PPGTT_CACHE64B);
+ 
+       ecochk = intel_uncore_read(uncore, GAM_ECOCHK);
+       if (IS_HASWELL(i915)) {
+               ecochk |= ECOCHK_PPGTT_WB_HSW;
+       } else {
+               ecochk |= ECOCHK_PPGTT_LLC_IVB;
+               ecochk &= ~ECOCHK_PPGTT_GFDT_IVB;
+       }
+       intel_uncore_write(uncore, GAM_ECOCHK, ecochk);
+ 
+       for_each_engine(engine, gt, id) {
+               /* GFX_MODE is per-ring on gen7+ */
+               ENGINE_WRITE(engine,
+                            RING_MODE_GEN7,
+                            _MASKED_BIT_ENABLE(GFX_PPGTT_ENABLE));
+       }
+ }
+ 
+ void gen6_ppgtt_enable(struct intel_gt *gt)
+ {
+       struct intel_uncore *uncore = gt->uncore;
+ 
+       intel_uncore_rmw(uncore,
+                        GAC_ECO_BITS,
+                        0,
+                        ECOBITS_SNB_BIT | ECOBITS_PPGTT_CACHE64B);
+ 
+       intel_uncore_rmw(uncore,
+                        GAB_CTL,
+                        0,
+                        GAB_CTL_CONT_AFTER_PAGEFAULT);
+ 
+       intel_uncore_rmw(uncore,
+                        GAM_ECOCHK,
+                        0,
+                        ECOCHK_SNB_BIT | ECOCHK_PPGTT_CACHE64B);
+ 
+       if (HAS_PPGTT(uncore->i915)) /* may be disabled for VT-d */
+               intel_uncore_write(uncore,
+                                  GFX_MODE,
+                                  _MASKED_BIT_ENABLE(GFX_PPGTT_ENABLE));
+ }
+ 
+ /* PPGTT support for Sandybdrige/Gen6 and later */
+ static void gen6_ppgtt_clear_range(struct i915_address_space *vm,
+                                  u64 start, u64 length)
+ {
+       struct gen6_ppgtt * const ppgtt = to_gen6_ppgtt(i915_vm_to_ppgtt(vm));
+       const unsigned int first_entry = start / I915_GTT_PAGE_SIZE;
+       const gen6_pte_t scratch_pte = vm->scratch[0].encode;
+       unsigned int pde = first_entry / GEN6_PTES;
+       unsigned int pte = first_entry % GEN6_PTES;
+       unsigned int num_entries = length / I915_GTT_PAGE_SIZE;
+ 
+       while (num_entries) {
+               struct i915_page_table * const pt =
+                       i915_pt_entry(ppgtt->base.pd, pde++);
+               const unsigned int count = min(num_entries, GEN6_PTES - pte);
+               gen6_pte_t *vaddr;
+ 
+               GEM_BUG_ON(px_base(pt) == px_base(&vm->scratch[1]));
+ 
+               num_entries -= count;
+ 
+               GEM_BUG_ON(count > atomic_read(&pt->used));
+               if (!atomic_sub_return(count, &pt->used))
+                       ppgtt->scan_for_unused_pt = true;
+ 
+               /*
+                * Note that the hw doesn't support removing PDE on the fly
+                * (they are cached inside the context with no means to
+                * invalidate the cache), so we can only reset the PTE
+                * entries back to scratch.
+                */
+ 
+               vaddr = kmap_atomic_px(pt);
+               memset32(vaddr + pte, scratch_pte, count);
+               kunmap_atomic(vaddr);
+ 
+               pte = 0;
+       }
+ }
+ 
+ static void gen6_ppgtt_insert_entries(struct i915_address_space *vm,
+                                     struct i915_vma *vma,
+                                     enum i915_cache_level cache_level,
+                                     u32 flags)
+ {
+       struct i915_ppgtt *ppgtt = i915_vm_to_ppgtt(vm);
+       struct i915_page_directory * const pd = ppgtt->pd;
+       unsigned int first_entry = vma->node.start / I915_GTT_PAGE_SIZE;
+       unsigned int act_pt = first_entry / GEN6_PTES;
+       unsigned int act_pte = first_entry % GEN6_PTES;
+       const u32 pte_encode = vm->pte_encode(0, cache_level, flags);
+       struct sgt_dma iter = sgt_dma(vma);
+       gen6_pte_t *vaddr;
+ 
+       GEM_BUG_ON(pd->entry[act_pt] == &vm->scratch[1]);
+ 
+       vaddr = kmap_atomic_px(i915_pt_entry(pd, act_pt));
+       do {
++              GEM_BUG_ON(iter.sg->length < I915_GTT_PAGE_SIZE);
+               vaddr[act_pte] = pte_encode | GEN6_PTE_ADDR_ENCODE(iter.dma);
+ 
+               iter.dma += I915_GTT_PAGE_SIZE;
+               if (iter.dma == iter.max) {
+                       iter.sg = __sg_next(iter.sg);
+                       if (!iter.sg)
+                               break;
+ 
+                       iter.dma = sg_dma_address(iter.sg);
+                       iter.max = iter.dma + iter.sg->length;
+               }
+ 
+               if (++act_pte == GEN6_PTES) {
+                       kunmap_atomic(vaddr);
+                       vaddr = kmap_atomic_px(i915_pt_entry(pd, ++act_pt));
+                       act_pte = 0;
+               }
+       } while (1);
+       kunmap_atomic(vaddr);
+ 
+       vma->page_sizes.gtt = I915_GTT_PAGE_SIZE;
+ }
+ 
+ static void gen6_flush_pd(struct gen6_ppgtt *ppgtt, u64 start, u64 end)
+ {
+       struct i915_page_directory * const pd = ppgtt->base.pd;
+       struct i915_page_table *pt;
+       unsigned int pde;
+ 
+       start = round_down(start, SZ_64K);
+       end = round_up(end, SZ_64K) - start;
+ 
+       mutex_lock(&ppgtt->flush);
+ 
+       gen6_for_each_pde(pt, pd, start, end, pde)
+               gen6_write_pde(ppgtt, pde, pt);
+ 
+       mb();
+       ioread32(ppgtt->pd_addr + pde - 1);
+       gen6_ggtt_invalidate(ppgtt->base.vm.gt->ggtt);
+       mb();
+ 
+       mutex_unlock(&ppgtt->flush);
+ }
+ 
+ static int gen6_alloc_va_range(struct i915_address_space *vm,
+                              u64 start, u64 length)
+ {
+       struct gen6_ppgtt *ppgtt = to_gen6_ppgtt(i915_vm_to_ppgtt(vm));
+       struct i915_page_directory * const pd = ppgtt->base.pd;
+       struct i915_page_table *pt, *alloc = NULL;
+       intel_wakeref_t wakeref;
+       u64 from = start;
+       unsigned int pde;
+       int ret = 0;
+ 
+       wakeref = intel_runtime_pm_get(&vm->i915->runtime_pm);
+ 
+       spin_lock(&pd->lock);
+       gen6_for_each_pde(pt, pd, start, length, pde) {
+               const unsigned int count = gen6_pte_count(start, length);
+ 
+               if (px_base(pt) == px_base(&vm->scratch[1])) {
+                       spin_unlock(&pd->lock);
+ 
+                       pt = fetch_and_zero(&alloc);
+                       if (!pt)
+                               pt = alloc_pt(vm);
+                       if (IS_ERR(pt)) {
+                               ret = PTR_ERR(pt);
+                               goto unwind_out;
+                       }
+ 
+                       fill32_px(pt, vm->scratch[0].encode);
+ 
+                       spin_lock(&pd->lock);
+                       if (pd->entry[pde] == &vm->scratch[1]) {
+                               pd->entry[pde] = pt;
+                       } else {
+                               alloc = pt;
+                               pt = pd->entry[pde];
+                       }
+               }
+ 
+               atomic_add(count, &pt->used);
+       }
+       spin_unlock(&pd->lock);
+ 
+       if (i915_vma_is_bound(ppgtt->vma, I915_VMA_GLOBAL_BIND))
+               gen6_flush_pd(ppgtt, from, start);
+ 
+       goto out;
+ 
+ unwind_out:
+       gen6_ppgtt_clear_range(vm, from, start - from);
+ out:
+       if (alloc)
+               free_px(vm, alloc);
+       intel_runtime_pm_put(&vm->i915->runtime_pm, wakeref);
+       return ret;
+ }
+ 
+ static int gen6_ppgtt_init_scratch(struct gen6_ppgtt *ppgtt)
+ {
+       struct i915_address_space * const vm = &ppgtt->base.vm;
+       struct i915_page_directory * const pd = ppgtt->base.pd;
+       int ret;
+ 
+       ret = setup_scratch_page(vm, __GFP_HIGHMEM);
+       if (ret)
+               return ret;
+ 
+       vm->scratch[0].encode =
+               vm->pte_encode(px_dma(&vm->scratch[0]),
+                              I915_CACHE_NONE, PTE_READ_ONLY);
+ 
+       if (unlikely(setup_page_dma(vm, px_base(&vm->scratch[1])))) {
+               cleanup_scratch_page(vm);
+               return -ENOMEM;
+       }
+ 
+       fill32_px(&vm->scratch[1], vm->scratch[0].encode);
+       memset_p(pd->entry, &vm->scratch[1], I915_PDES);
+ 
+       return 0;
+ }
+ 
+ static void gen6_ppgtt_free_pd(struct gen6_ppgtt *ppgtt)
+ {
+       struct i915_page_directory * const pd = ppgtt->base.pd;
+       struct i915_page_dma * const scratch =
+               px_base(&ppgtt->base.vm.scratch[1]);
+       struct i915_page_table *pt;
+       u32 pde;
+ 
+       gen6_for_all_pdes(pt, pd, pde)
+               if (px_base(pt) != scratch)
+                       free_px(&ppgtt->base.vm, pt);
+ }
+ 
+ static void gen6_ppgtt_cleanup(struct i915_address_space *vm)
+ {
+       struct gen6_ppgtt *ppgtt = to_gen6_ppgtt(i915_vm_to_ppgtt(vm));
+ 
+       __i915_vma_put(ppgtt->vma);
+ 
+       gen6_ppgtt_free_pd(ppgtt);
+       free_scratch(vm);
+ 
+       mutex_destroy(&ppgtt->flush);
+       mutex_destroy(&ppgtt->pin_mutex);
+       kfree(ppgtt->base.pd);
+ }
+ 
+ static int pd_vma_set_pages(struct i915_vma *vma)
+ {
+       vma->pages = ERR_PTR(-ENODEV);
+       return 0;
+ }
+ 
+ static void pd_vma_clear_pages(struct i915_vma *vma)
+ {
+       GEM_BUG_ON(!vma->pages);
+ 
+       vma->pages = NULL;
+ }
+ 
+ static int pd_vma_bind(struct i915_vma *vma,
+                      enum i915_cache_level cache_level,
+                      u32 unused)
+ {
+       struct i915_ggtt *ggtt = i915_vm_to_ggtt(vma->vm);
+       struct gen6_ppgtt *ppgtt = vma->private;
+       u32 ggtt_offset = i915_ggtt_offset(vma) / I915_GTT_PAGE_SIZE;
+ 
+       px_base(ppgtt->base.pd)->ggtt_offset = ggtt_offset * sizeof(gen6_pte_t);
+       ppgtt->pd_addr = (gen6_pte_t __iomem *)ggtt->gsm + ggtt_offset;
+ 
+       gen6_flush_pd(ppgtt, 0, ppgtt->base.vm.total);
+       return 0;
+ }
+ 
+ static void pd_vma_unbind(struct i915_vma *vma)
+ {
+       struct gen6_ppgtt *ppgtt = vma->private;
+       struct i915_page_directory * const pd = ppgtt->base.pd;
+       struct i915_page_dma * const scratch =
+               px_base(&ppgtt->base.vm.scratch[1]);
+       struct i915_page_table *pt;
+       unsigned int pde;
+ 
+       if (!ppgtt->scan_for_unused_pt)
+               return;
+ 
+       /* Free all no longer used page tables */
+       gen6_for_all_pdes(pt, ppgtt->base.pd, pde) {
+               if (px_base(pt) == scratch || atomic_read(&pt->used))
+                       continue;
+ 
+               free_px(&ppgtt->base.vm, pt);
+               pd->entry[pde] = scratch;
+       }
+ 
+       ppgtt->scan_for_unused_pt = false;
+ }
+ 
+ static const struct i915_vma_ops pd_vma_ops = {
+       .set_pages = pd_vma_set_pages,
+       .clear_pages = pd_vma_clear_pages,
+       .bind_vma = pd_vma_bind,
+       .unbind_vma = pd_vma_unbind,
+ };
+ 
+ static struct i915_vma *pd_vma_create(struct gen6_ppgtt *ppgtt, int size)
+ {
+       struct i915_ggtt *ggtt = ppgtt->base.vm.gt->ggtt;
+       struct i915_vma *vma;
+ 
+       GEM_BUG_ON(!IS_ALIGNED(size, I915_GTT_PAGE_SIZE));
+       GEM_BUG_ON(size > ggtt->vm.total);
+ 
+       vma = i915_vma_alloc();
+       if (!vma)
+               return ERR_PTR(-ENOMEM);
+ 
+       i915_active_init(&vma->active, NULL, NULL);
+ 
+       kref_init(&vma->ref);
+       mutex_init(&vma->pages_mutex);
+       vma->vm = i915_vm_get(&ggtt->vm);
+       vma->ops = &pd_vma_ops;
+       vma->private = ppgtt;
+ 
+       vma->size = size;
+       vma->fence_size = size;
+       atomic_set(&vma->flags, I915_VMA_GGTT);
+       vma->ggtt_view.type = I915_GGTT_VIEW_ROTATED; /* prevent fencing */
+ 
+       INIT_LIST_HEAD(&vma->obj_link);
+       INIT_LIST_HEAD(&vma->closed_link);
+ 
+       return vma;
+ }
+ 
+ int gen6_ppgtt_pin(struct i915_ppgtt *base)
+ {
+       struct gen6_ppgtt *ppgtt = to_gen6_ppgtt(base);
+       int err;
+ 
+       GEM_BUG_ON(!atomic_read(&ppgtt->base.vm.open));
+ 
+       /*
+        * Workaround the limited maximum vma->pin_count and the aliasing_ppgtt
+        * which will be pinned into every active context.
+        * (When vma->pin_count becomes atomic, I expect we will naturally
+        * need a larger, unpacked, type and kill this redundancy.)
+        */
+       if (atomic_add_unless(&ppgtt->pin_count, 1, 0))
+               return 0;
+ 
+       if (mutex_lock_interruptible(&ppgtt->pin_mutex))
+               return -EINTR;
+ 
+       /*
+        * PPGTT PDEs reside in the GGTT and consists of 512 entries. The
+        * allocator works in address space sizes, so it's multiplied by page
+        * size. We allocate at the top of the GTT to avoid fragmentation.
+        */
+       err = 0;
+       if (!atomic_read(&ppgtt->pin_count))
+               err = i915_ggtt_pin(ppgtt->vma, GEN6_PD_ALIGN, PIN_HIGH);
+       if (!err)
+               atomic_inc(&ppgtt->pin_count);
+       mutex_unlock(&ppgtt->pin_mutex);
+ 
+       return err;
+ }
+ 
+ void gen6_ppgtt_unpin(struct i915_ppgtt *base)
+ {
+       struct gen6_ppgtt *ppgtt = to_gen6_ppgtt(base);
+ 
+       GEM_BUG_ON(!atomic_read(&ppgtt->pin_count));
+       if (atomic_dec_and_test(&ppgtt->pin_count))
+               i915_vma_unpin(ppgtt->vma);
+ }
+ 
+ void gen6_ppgtt_unpin_all(struct i915_ppgtt *base)
+ {
+       struct gen6_ppgtt *ppgtt = to_gen6_ppgtt(base);
+ 
+       if (!atomic_read(&ppgtt->pin_count))
+               return;
+ 
+       i915_vma_unpin(ppgtt->vma);
+       atomic_set(&ppgtt->pin_count, 0);
+ }
+ 
+ struct i915_ppgtt *gen6_ppgtt_create(struct intel_gt *gt)
+ {
+       struct i915_ggtt * const ggtt = gt->ggtt;
+       struct gen6_ppgtt *ppgtt;
+       int err;
+ 
+       ppgtt = kzalloc(sizeof(*ppgtt), GFP_KERNEL);
+       if (!ppgtt)
+               return ERR_PTR(-ENOMEM);
+ 
+       mutex_init(&ppgtt->flush);
+       mutex_init(&ppgtt->pin_mutex);
+ 
+       ppgtt_init(&ppgtt->base, gt);
+       ppgtt->base.vm.top = 1;
+ 
+       ppgtt->base.vm.bind_async_flags = I915_VMA_LOCAL_BIND;
+       ppgtt->base.vm.allocate_va_range = gen6_alloc_va_range;
+       ppgtt->base.vm.clear_range = gen6_ppgtt_clear_range;
+       ppgtt->base.vm.insert_entries = gen6_ppgtt_insert_entries;
+       ppgtt->base.vm.cleanup = gen6_ppgtt_cleanup;
+ 
+       ppgtt->base.vm.pte_encode = ggtt->vm.pte_encode;
+ 
+       ppgtt->base.pd = __alloc_pd(sizeof(*ppgtt->base.pd));
+       if (!ppgtt->base.pd) {
+               err = -ENOMEM;
+               goto err_free;
+       }
+ 
+       err = gen6_ppgtt_init_scratch(ppgtt);
+       if (err)
+               goto err_pd;
+ 
+       ppgtt->vma = pd_vma_create(ppgtt, GEN6_PD_SIZE);
+       if (IS_ERR(ppgtt->vma)) {
+               err = PTR_ERR(ppgtt->vma);
+               goto err_scratch;
+       }
+ 
+       return &ppgtt->base;
+ 
+ err_scratch:
+       free_scratch(&ppgtt->base.vm);
+ err_pd:
+       kfree(ppgtt->base.pd);
+ err_free:
+       mutex_destroy(&ppgtt->pin_mutex);
+       kfree(ppgtt);
+       return ERR_PTR(err);
+ }
 
--- /dev/null
+ // SPDX-License-Identifier: MIT
+ /*
+  * Copyright Â© 2020 Intel Corporation
+  */
+ 
+ #include <linux/log2.h>
+ 
+ #include "gen8_ppgtt.h"
+ #include "i915_scatterlist.h"
+ #include "i915_trace.h"
+ #include "i915_vgpu.h"
+ #include "intel_gt.h"
+ #include "intel_gtt.h"
+ 
+ static u64 gen8_pde_encode(const dma_addr_t addr,
+                          const enum i915_cache_level level)
+ {
+       u64 pde = addr | _PAGE_PRESENT | _PAGE_RW;
+ 
+       if (level != I915_CACHE_NONE)
+               pde |= PPAT_CACHED_PDE;
+       else
+               pde |= PPAT_UNCACHED;
+ 
+       return pde;
+ }
+ 
+ static void gen8_ppgtt_notify_vgt(struct i915_ppgtt *ppgtt, bool create)
+ {
+       struct drm_i915_private *i915 = ppgtt->vm.i915;
+       struct intel_uncore *uncore = ppgtt->vm.gt->uncore;
+       enum vgt_g2v_type msg;
+       int i;
+ 
+       if (create)
+               atomic_inc(px_used(ppgtt->pd)); /* never remove */
+       else
+               atomic_dec(px_used(ppgtt->pd));
+ 
+       mutex_lock(&i915->vgpu.lock);
+ 
+       if (i915_vm_is_4lvl(&ppgtt->vm)) {
+               const u64 daddr = px_dma(ppgtt->pd);
+ 
+               intel_uncore_write(uncore,
+                                  vgtif_reg(pdp[0].lo), lower_32_bits(daddr));
+               intel_uncore_write(uncore,
+                                  vgtif_reg(pdp[0].hi), upper_32_bits(daddr));
+ 
+               msg = create ?
+                       VGT_G2V_PPGTT_L4_PAGE_TABLE_CREATE :
+                       VGT_G2V_PPGTT_L4_PAGE_TABLE_DESTROY;
+       } else {
+               for (i = 0; i < GEN8_3LVL_PDPES; i++) {
+                       const u64 daddr = i915_page_dir_dma_addr(ppgtt, i);
+ 
+                       intel_uncore_write(uncore,
+                                          vgtif_reg(pdp[i].lo),
+                                          lower_32_bits(daddr));
+                       intel_uncore_write(uncore,
+                                          vgtif_reg(pdp[i].hi),
+                                          upper_32_bits(daddr));
+               }
+ 
+               msg = create ?
+                       VGT_G2V_PPGTT_L3_PAGE_TABLE_CREATE :
+                       VGT_G2V_PPGTT_L3_PAGE_TABLE_DESTROY;
+       }
+ 
+       /* g2v_notify atomically (via hv trap) consumes the message packet. */
+       intel_uncore_write(uncore, vgtif_reg(g2v_notify), msg);
+ 
+       mutex_unlock(&i915->vgpu.lock);
+ }
+ 
+ /* Index shifts into the pagetable are offset by GEN8_PTE_SHIFT [12] */
+ #define GEN8_PAGE_SIZE (SZ_4K) /* page and page-directory sizes are the same */
+ #define GEN8_PTE_SHIFT (ilog2(GEN8_PAGE_SIZE))
+ #define GEN8_PDES (GEN8_PAGE_SIZE / sizeof(u64))
+ #define gen8_pd_shift(lvl) ((lvl) * ilog2(GEN8_PDES))
+ #define gen8_pd_index(i, lvl) i915_pde_index((i), gen8_pd_shift(lvl))
+ #define __gen8_pte_shift(lvl) (GEN8_PTE_SHIFT + gen8_pd_shift(lvl))
+ #define __gen8_pte_index(a, lvl) i915_pde_index((a), __gen8_pte_shift(lvl))
+ 
+ #define as_pd(x) container_of((x), typeof(struct i915_page_directory), pt)
+ 
+ static inline unsigned int
+ gen8_pd_range(u64 start, u64 end, int lvl, unsigned int *idx)
+ {
+       const int shift = gen8_pd_shift(lvl);
+       const u64 mask = ~0ull << gen8_pd_shift(lvl + 1);
+ 
+       GEM_BUG_ON(start >= end);
+       end += ~mask >> gen8_pd_shift(1);
+ 
+       *idx = i915_pde_index(start, shift);
+       if ((start ^ end) & mask)
+               return GEN8_PDES - *idx;
+       else
+               return i915_pde_index(end, shift) - *idx;
+ }
+ 
+ static inline bool gen8_pd_contains(u64 start, u64 end, int lvl)
+ {
+       const u64 mask = ~0ull << gen8_pd_shift(lvl + 1);
+ 
+       GEM_BUG_ON(start >= end);
+       return (start ^ end) & mask && (start & ~mask) == 0;
+ }
+ 
+ static inline unsigned int gen8_pt_count(u64 start, u64 end)
+ {
+       GEM_BUG_ON(start >= end);
+       if ((start ^ end) >> gen8_pd_shift(1))
+               return GEN8_PDES - (start & (GEN8_PDES - 1));
+       else
+               return end - start;
+ }
+ 
+ static inline unsigned int
+ gen8_pd_top_count(const struct i915_address_space *vm)
+ {
+       unsigned int shift = __gen8_pte_shift(vm->top);
+       return (vm->total + (1ull << shift) - 1) >> shift;
+ }
+ 
+ static inline struct i915_page_directory *
+ gen8_pdp_for_page_index(struct i915_address_space * const vm, const u64 idx)
+ {
+       struct i915_ppgtt * const ppgtt = i915_vm_to_ppgtt(vm);
+ 
+       if (vm->top == 2)
+               return ppgtt->pd;
+       else
+               return i915_pd_entry(ppgtt->pd, gen8_pd_index(idx, vm->top));
+ }
+ 
+ static inline struct i915_page_directory *
+ gen8_pdp_for_page_address(struct i915_address_space * const vm, const u64 addr)
+ {
+       return gen8_pdp_for_page_index(vm, addr >> GEN8_PTE_SHIFT);
+ }
+ 
+ static void __gen8_ppgtt_cleanup(struct i915_address_space *vm,
+                                struct i915_page_directory *pd,
+                                int count, int lvl)
+ {
+       if (lvl) {
+               void **pde = pd->entry;
+ 
+               do {
+                       if (!*pde)
+                               continue;
+ 
+                       __gen8_ppgtt_cleanup(vm, *pde, GEN8_PDES, lvl - 1);
+               } while (pde++, --count);
+       }
+ 
+       free_px(vm, pd);
+ }
+ 
+ static void gen8_ppgtt_cleanup(struct i915_address_space *vm)
+ {
+       struct i915_ppgtt *ppgtt = i915_vm_to_ppgtt(vm);
+ 
+       if (intel_vgpu_active(vm->i915))
+               gen8_ppgtt_notify_vgt(ppgtt, false);
+ 
+       __gen8_ppgtt_cleanup(vm, ppgtt->pd, gen8_pd_top_count(vm), vm->top);
+       free_scratch(vm);
+ }
+ 
+ static u64 __gen8_ppgtt_clear(struct i915_address_space * const vm,
+                             struct i915_page_directory * const pd,
+                             u64 start, const u64 end, int lvl)
+ {
+       const struct i915_page_scratch * const scratch = &vm->scratch[lvl];
+       unsigned int idx, len;
+ 
+       GEM_BUG_ON(end > vm->total >> GEN8_PTE_SHIFT);
+ 
+       len = gen8_pd_range(start, end, lvl--, &idx);
+       DBG("%s(%p):{ lvl:%d, start:%llx, end:%llx, idx:%d, len:%d, used:%d }\n",
+           __func__, vm, lvl + 1, start, end,
+           idx, len, atomic_read(px_used(pd)));
+       GEM_BUG_ON(!len || len >= atomic_read(px_used(pd)));
+ 
+       do {
+               struct i915_page_table *pt = pd->entry[idx];
+ 
+               if (atomic_fetch_inc(&pt->used) >> gen8_pd_shift(1) &&
+                   gen8_pd_contains(start, end, lvl)) {
+                       DBG("%s(%p):{ lvl:%d, idx:%d, start:%llx, end:%llx } removing pd\n",
+                           __func__, vm, lvl + 1, idx, start, end);
+                       clear_pd_entry(pd, idx, scratch);
+                       __gen8_ppgtt_cleanup(vm, as_pd(pt), I915_PDES, lvl);
+                       start += (u64)I915_PDES << gen8_pd_shift(lvl);
+                       continue;
+               }
+ 
+               if (lvl) {
+                       start = __gen8_ppgtt_clear(vm, as_pd(pt),
+                                                  start, end, lvl);
+               } else {
+                       unsigned int count;
+                       u64 *vaddr;
+ 
+                       count = gen8_pt_count(start, end);
+                       DBG("%s(%p):{ lvl:%d, start:%llx, end:%llx, idx:%d, len:%d, used:%d } removing pte\n",
+                           __func__, vm, lvl, start, end,
+                           gen8_pd_index(start, 0), count,
+                           atomic_read(&pt->used));
+                       GEM_BUG_ON(!count || count >= atomic_read(&pt->used));
+ 
+                       vaddr = kmap_atomic_px(pt);
+                       memset64(vaddr + gen8_pd_index(start, 0),
+                                vm->scratch[0].encode,
+                                count);
+                       kunmap_atomic(vaddr);
+ 
+                       atomic_sub(count, &pt->used);
+                       start += count;
+               }
+ 
+               if (release_pd_entry(pd, idx, pt, scratch))
+                       free_px(vm, pt);
+       } while (idx++, --len);
+ 
+       return start;
+ }
+ 
+ static void gen8_ppgtt_clear(struct i915_address_space *vm,
+                            u64 start, u64 length)
+ {
+       GEM_BUG_ON(!IS_ALIGNED(start, BIT_ULL(GEN8_PTE_SHIFT)));
+       GEM_BUG_ON(!IS_ALIGNED(length, BIT_ULL(GEN8_PTE_SHIFT)));
+       GEM_BUG_ON(range_overflows(start, length, vm->total));
+ 
+       start >>= GEN8_PTE_SHIFT;
+       length >>= GEN8_PTE_SHIFT;
+       GEM_BUG_ON(length == 0);
+ 
+       __gen8_ppgtt_clear(vm, i915_vm_to_ppgtt(vm)->pd,
+                          start, start + length, vm->top);
+ }
+ 
+ static int __gen8_ppgtt_alloc(struct i915_address_space * const vm,
+                             struct i915_page_directory * const pd,
+                             u64 * const start, const u64 end, int lvl)
+ {
+       const struct i915_page_scratch * const scratch = &vm->scratch[lvl];
+       struct i915_page_table *alloc = NULL;
+       unsigned int idx, len;
+       int ret = 0;
+ 
+       GEM_BUG_ON(end > vm->total >> GEN8_PTE_SHIFT);
+ 
+       len = gen8_pd_range(*start, end, lvl--, &idx);
+       DBG("%s(%p):{ lvl:%d, start:%llx, end:%llx, idx:%d, len:%d, used:%d }\n",
+           __func__, vm, lvl + 1, *start, end,
+           idx, len, atomic_read(px_used(pd)));
+       GEM_BUG_ON(!len || (idx + len - 1) >> gen8_pd_shift(1));
+ 
+       spin_lock(&pd->lock);
+       GEM_BUG_ON(!atomic_read(px_used(pd))); /* Must be pinned! */
+       do {
+               struct i915_page_table *pt = pd->entry[idx];
+ 
+               if (!pt) {
+                       spin_unlock(&pd->lock);
+ 
+                       DBG("%s(%p):{ lvl:%d, idx:%d } allocating new tree\n",
+                           __func__, vm, lvl + 1, idx);
+ 
+                       pt = fetch_and_zero(&alloc);
+                       if (lvl) {
+                               if (!pt) {
+                                       pt = &alloc_pd(vm)->pt;
+                                       if (IS_ERR(pt)) {
+                                               ret = PTR_ERR(pt);
+                                               goto out;
+                                       }
+                               }
+ 
+                               fill_px(pt, vm->scratch[lvl].encode);
+                       } else {
+                               if (!pt) {
+                                       pt = alloc_pt(vm);
+                                       if (IS_ERR(pt)) {
+                                               ret = PTR_ERR(pt);
+                                               goto out;
+                                       }
+                               }
+ 
+                               if (intel_vgpu_active(vm->i915) ||
+                                   gen8_pt_count(*start, end) < I915_PDES)
+                                       fill_px(pt, vm->scratch[lvl].encode);
+                       }
+ 
+                       spin_lock(&pd->lock);
+                       if (likely(!pd->entry[idx]))
+                               set_pd_entry(pd, idx, pt);
+                       else
+                               alloc = pt, pt = pd->entry[idx];
+               }
+ 
+               if (lvl) {
+                       atomic_inc(&pt->used);
+                       spin_unlock(&pd->lock);
+ 
+                       ret = __gen8_ppgtt_alloc(vm, as_pd(pt),
+                                                start, end, lvl);
+                       if (unlikely(ret)) {
+                               if (release_pd_entry(pd, idx, pt, scratch))
+                                       free_px(vm, pt);
+                               goto out;
+                       }
+ 
+                       spin_lock(&pd->lock);
+                       atomic_dec(&pt->used);
+                       GEM_BUG_ON(!atomic_read(&pt->used));
+               } else {
+                       unsigned int count = gen8_pt_count(*start, end);
+ 
+                       DBG("%s(%p):{ lvl:%d, start:%llx, end:%llx, idx:%d, len:%d, used:%d } inserting pte\n",
+                           __func__, vm, lvl, *start, end,
+                           gen8_pd_index(*start, 0), count,
+                           atomic_read(&pt->used));
+ 
+                       atomic_add(count, &pt->used);
+                       /* All other pdes may be simultaneously removed */
+                       GEM_BUG_ON(atomic_read(&pt->used) > NALLOC * I915_PDES);
+                       *start += count;
+               }
+       } while (idx++, --len);
+       spin_unlock(&pd->lock);
+ out:
+       if (alloc)
+               free_px(vm, alloc);
+       return ret;
+ }
+ 
+ static int gen8_ppgtt_alloc(struct i915_address_space *vm,
+                           u64 start, u64 length)
+ {
+       u64 from;
+       int err;
+ 
+       GEM_BUG_ON(!IS_ALIGNED(start, BIT_ULL(GEN8_PTE_SHIFT)));
+       GEM_BUG_ON(!IS_ALIGNED(length, BIT_ULL(GEN8_PTE_SHIFT)));
+       GEM_BUG_ON(range_overflows(start, length, vm->total));
+ 
+       start >>= GEN8_PTE_SHIFT;
+       length >>= GEN8_PTE_SHIFT;
+       GEM_BUG_ON(length == 0);
+       from = start;
+ 
+       err = __gen8_ppgtt_alloc(vm, i915_vm_to_ppgtt(vm)->pd,
+                                &start, start + length, vm->top);
+       if (unlikely(err && from != start))
+               __gen8_ppgtt_clear(vm, i915_vm_to_ppgtt(vm)->pd,
+                                  from, start, vm->top);
+ 
+       return err;
+ }
+ 
+ static __always_inline u64
+ gen8_ppgtt_insert_pte(struct i915_ppgtt *ppgtt,
+                     struct i915_page_directory *pdp,
+                     struct sgt_dma *iter,
+                     u64 idx,
+                     enum i915_cache_level cache_level,
+                     u32 flags)
+ {
+       struct i915_page_directory *pd;
+       const gen8_pte_t pte_encode = gen8_pte_encode(0, cache_level, flags);
+       gen8_pte_t *vaddr;
+ 
+       pd = i915_pd_entry(pdp, gen8_pd_index(idx, 2));
+       vaddr = kmap_atomic_px(i915_pt_entry(pd, gen8_pd_index(idx, 1)));
+       do {
++              GEM_BUG_ON(iter->sg->length < I915_GTT_PAGE_SIZE);
+               vaddr[gen8_pd_index(idx, 0)] = pte_encode | iter->dma;
+ 
+               iter->dma += I915_GTT_PAGE_SIZE;
+               if (iter->dma >= iter->max) {
+                       iter->sg = __sg_next(iter->sg);
+                       if (!iter->sg) {
+                               idx = 0;
+                               break;
+                       }
+ 
+                       iter->dma = sg_dma_address(iter->sg);
+                       iter->max = iter->dma + iter->sg->length;
+               }
+ 
+               if (gen8_pd_index(++idx, 0) == 0) {
+                       if (gen8_pd_index(idx, 1) == 0) {
+                               /* Limited by sg length for 3lvl */
+                               if (gen8_pd_index(idx, 2) == 0)
+                                       break;
+ 
+                               pd = pdp->entry[gen8_pd_index(idx, 2)];
+                       }
+ 
+                       kunmap_atomic(vaddr);
+                       vaddr = kmap_atomic_px(i915_pt_entry(pd, gen8_pd_index(idx, 1)));
+               }
+       } while (1);
+       kunmap_atomic(vaddr);
+ 
+       return idx;
+ }
+ 
+ static void gen8_ppgtt_insert_huge(struct i915_vma *vma,
+                                  struct sgt_dma *iter,
+                                  enum i915_cache_level cache_level,
+                                  u32 flags)
+ {
+       const gen8_pte_t pte_encode = gen8_pte_encode(0, cache_level, flags);
+       u64 start = vma->node.start;
+       dma_addr_t rem = iter->sg->length;
+ 
+       GEM_BUG_ON(!i915_vm_is_4lvl(vma->vm));
+ 
+       do {
+               struct i915_page_directory * const pdp =
+                       gen8_pdp_for_page_address(vma->vm, start);
+               struct i915_page_directory * const pd =
+                       i915_pd_entry(pdp, __gen8_pte_index(start, 2));
+               gen8_pte_t encode = pte_encode;
+               unsigned int maybe_64K = -1;
+               unsigned int page_size;
+               gen8_pte_t *vaddr;
+               u16 index;
+ 
+               if (vma->page_sizes.sg & I915_GTT_PAGE_SIZE_2M &&
+                   IS_ALIGNED(iter->dma, I915_GTT_PAGE_SIZE_2M) &&
+                   rem >= I915_GTT_PAGE_SIZE_2M &&
+                   !__gen8_pte_index(start, 0)) {
+                       index = __gen8_pte_index(start, 1);
+                       encode |= GEN8_PDE_PS_2M;
+                       page_size = I915_GTT_PAGE_SIZE_2M;
+ 
+                       vaddr = kmap_atomic_px(pd);
+               } else {
+                       struct i915_page_table *pt =
+                               i915_pt_entry(pd, __gen8_pte_index(start, 1));
+ 
+                       index = __gen8_pte_index(start, 0);
+                       page_size = I915_GTT_PAGE_SIZE;
+ 
+                       if (!index &&
+                           vma->page_sizes.sg & I915_GTT_PAGE_SIZE_64K &&
+                           IS_ALIGNED(iter->dma, I915_GTT_PAGE_SIZE_64K) &&
+                           (IS_ALIGNED(rem, I915_GTT_PAGE_SIZE_64K) ||
+                            rem >= (I915_PDES - index) * I915_GTT_PAGE_SIZE))
+                               maybe_64K = __gen8_pte_index(start, 1);
+ 
+                       vaddr = kmap_atomic_px(pt);
+               }
+ 
+               do {
+                       GEM_BUG_ON(iter->sg->length < page_size);
+                       vaddr[index++] = encode | iter->dma;
+ 
+                       start += page_size;
+                       iter->dma += page_size;
+                       rem -= page_size;
+                       if (iter->dma >= iter->max) {
+                               iter->sg = __sg_next(iter->sg);
+                               if (!iter->sg)
+                                       break;
+ 
+                               rem = iter->sg->length;
+                               iter->dma = sg_dma_address(iter->sg);
+                               iter->max = iter->dma + rem;
+ 
+                               if (maybe_64K != -1 && index < I915_PDES &&
+                                   !(IS_ALIGNED(iter->dma, I915_GTT_PAGE_SIZE_64K) &&
+                                     (IS_ALIGNED(rem, I915_GTT_PAGE_SIZE_64K) ||
+                                      rem >= (I915_PDES - index) * I915_GTT_PAGE_SIZE)))
+                                       maybe_64K = -1;
+ 
+                               if (unlikely(!IS_ALIGNED(iter->dma, page_size)))
+                                       break;
+                       }
+               } while (rem >= page_size && index < I915_PDES);
+ 
+               kunmap_atomic(vaddr);
+ 
+               /*
+                * Is it safe to mark the 2M block as 64K? -- Either we have
+                * filled whole page-table with 64K entries, or filled part of
+                * it and have reached the end of the sg table and we have
+                * enough padding.
+                */
+               if (maybe_64K != -1 &&
+                   (index == I915_PDES ||
+                    (i915_vm_has_scratch_64K(vma->vm) &&
+                     !iter->sg && IS_ALIGNED(vma->node.start +
+                                             vma->node.size,
+                                             I915_GTT_PAGE_SIZE_2M)))) {
+                       vaddr = kmap_atomic_px(pd);
+                       vaddr[maybe_64K] |= GEN8_PDE_IPS_64K;
+                       kunmap_atomic(vaddr);
+                       page_size = I915_GTT_PAGE_SIZE_64K;
+ 
+                       /*
+                        * We write all 4K page entries, even when using 64K
+                        * pages. In order to verify that the HW isn't cheating
+                        * by using the 4K PTE instead of the 64K PTE, we want
+                        * to remove all the surplus entries. If the HW skipped
+                        * the 64K PTE, it will read/write into the scratch page
+                        * instead - which we detect as missing results during
+                        * selftests.
+                        */
+                       if (I915_SELFTEST_ONLY(vma->vm->scrub_64K)) {
+                               u16 i;
+ 
+                               encode = vma->vm->scratch[0].encode;
+                               vaddr = kmap_atomic_px(i915_pt_entry(pd, maybe_64K));
+ 
+                               for (i = 1; i < index; i += 16)
+                                       memset64(vaddr + i, encode, 15);
+ 
+                               kunmap_atomic(vaddr);
+                       }
+               }
+ 
+               vma->page_sizes.gtt |= page_size;
+       } while (iter->sg);
+ }
+ 
+ static void gen8_ppgtt_insert(struct i915_address_space *vm,
+                             struct i915_vma *vma,
+                             enum i915_cache_level cache_level,
+                             u32 flags)
+ {
+       struct i915_ppgtt * const ppgtt = i915_vm_to_ppgtt(vm);
+       struct sgt_dma iter = sgt_dma(vma);
+ 
+       if (vma->page_sizes.sg > I915_GTT_PAGE_SIZE) {
+               gen8_ppgtt_insert_huge(vma, &iter, cache_level, flags);
+       } else  {
+               u64 idx = vma->node.start >> GEN8_PTE_SHIFT;
+ 
+               do {
+                       struct i915_page_directory * const pdp =
+                               gen8_pdp_for_page_index(vm, idx);
+ 
+                       idx = gen8_ppgtt_insert_pte(ppgtt, pdp, &iter, idx,
+                                                   cache_level, flags);
+               } while (idx);
+ 
+               vma->page_sizes.gtt = I915_GTT_PAGE_SIZE;
+       }
+ }
+ 
+ static int gen8_init_scratch(struct i915_address_space *vm)
+ {
+       int ret;
+       int i;
+ 
+       /*
+        * If everybody agrees to not to write into the scratch page,
+        * we can reuse it for all vm, keeping contexts and processes separate.
+        */
+       if (vm->has_read_only && vm->gt->vm && !i915_is_ggtt(vm->gt->vm)) {
+               struct i915_address_space *clone = vm->gt->vm;
+ 
+               GEM_BUG_ON(!clone->has_read_only);
+ 
+               vm->scratch_order = clone->scratch_order;
+               memcpy(vm->scratch, clone->scratch, sizeof(vm->scratch));
+               px_dma(&vm->scratch[0]) = 0; /* no xfer of ownership */
+               return 0;
+       }
+ 
+       ret = setup_scratch_page(vm, __GFP_HIGHMEM);
+       if (ret)
+               return ret;
+ 
+       vm->scratch[0].encode =
+               gen8_pte_encode(px_dma(&vm->scratch[0]),
+                               I915_CACHE_LLC, vm->has_read_only);
+ 
+       for (i = 1; i <= vm->top; i++) {
+               if (unlikely(setup_page_dma(vm, px_base(&vm->scratch[i]))))
+                       goto free_scratch;
+ 
+               fill_px(&vm->scratch[i], vm->scratch[i - 1].encode);
+               vm->scratch[i].encode =
+                       gen8_pde_encode(px_dma(&vm->scratch[i]),
+                                       I915_CACHE_LLC);
+       }
+ 
+       return 0;
+ 
+ free_scratch:
+       free_scratch(vm);
+       return -ENOMEM;
+ }
+ 
+ static int gen8_preallocate_top_level_pdp(struct i915_ppgtt *ppgtt)
+ {
+       struct i915_address_space *vm = &ppgtt->vm;
+       struct i915_page_directory *pd = ppgtt->pd;
+       unsigned int idx;
+ 
+       GEM_BUG_ON(vm->top != 2);
+       GEM_BUG_ON(gen8_pd_top_count(vm) != GEN8_3LVL_PDPES);
+ 
+       for (idx = 0; idx < GEN8_3LVL_PDPES; idx++) {
+               struct i915_page_directory *pde;
+ 
+               pde = alloc_pd(vm);
+               if (IS_ERR(pde))
+                       return PTR_ERR(pde);
+ 
+               fill_px(pde, vm->scratch[1].encode);
+               set_pd_entry(pd, idx, pde);
+               atomic_inc(px_used(pde)); /* keep pinned */
+       }
+       wmb();
+ 
+       return 0;
+ }
+ 
+ static struct i915_page_directory *
+ gen8_alloc_top_pd(struct i915_address_space *vm)
+ {
+       const unsigned int count = gen8_pd_top_count(vm);
+       struct i915_page_directory *pd;
+ 
+       GEM_BUG_ON(count > ARRAY_SIZE(pd->entry));
+ 
+       pd = __alloc_pd(offsetof(typeof(*pd), entry[count]));
+       if (unlikely(!pd))
+               return ERR_PTR(-ENOMEM);
+ 
+       if (unlikely(setup_page_dma(vm, px_base(pd)))) {
+               kfree(pd);
+               return ERR_PTR(-ENOMEM);
+       }
+ 
+       fill_page_dma(px_base(pd), vm->scratch[vm->top].encode, count);
+       atomic_inc(px_used(pd)); /* mark as pinned */
+       return pd;
+ }
+ 
+ /*
+  * GEN8 legacy ppgtt programming is accomplished through a max 4 PDP registers
+  * with a net effect resembling a 2-level page table in normal x86 terms. Each
+  * PDP represents 1GB of memory 4 * 512 * 512 * 4096 = 4GB legacy 32b address
+  * space.
+  *
+  */
+ struct i915_ppgtt *gen8_ppgtt_create(struct intel_gt *gt)
+ {
+       struct i915_ppgtt *ppgtt;
+       int err;
+ 
+       ppgtt = kzalloc(sizeof(*ppgtt), GFP_KERNEL);
+       if (!ppgtt)
+               return ERR_PTR(-ENOMEM);
+ 
+       ppgtt_init(ppgtt, gt);
+       ppgtt->vm.top = i915_vm_is_4lvl(&ppgtt->vm) ? 3 : 2;
+ 
+       /*
+        * From bdw, there is hw support for read-only pages in the PPGTT.
+        *
+        * Gen11 has HSDES#:1807136187 unresolved. Disable ro support
+        * for now.
+        *
+        * Gen12 has inherited the same read-only fault issue from gen11.
+        */
+       ppgtt->vm.has_read_only = !IS_GEN_RANGE(gt->i915, 11, 12);
+ 
+       /*
+        * There are only few exceptions for gen >=6. chv and bxt.
+        * And we are not sure about the latter so play safe for now.
+        */
+       if (IS_CHERRYVIEW(gt->i915) || IS_BROXTON(gt->i915))
+               ppgtt->vm.pt_kmap_wc = true;
+ 
+       err = gen8_init_scratch(&ppgtt->vm);
+       if (err)
+               goto err_free;
+ 
+       ppgtt->pd = gen8_alloc_top_pd(&ppgtt->vm);
+       if (IS_ERR(ppgtt->pd)) {
+               err = PTR_ERR(ppgtt->pd);
+               goto err_free_scratch;
+       }
+ 
+       if (!i915_vm_is_4lvl(&ppgtt->vm)) {
+               err = gen8_preallocate_top_level_pdp(ppgtt);
+               if (err)
+                       goto err_free_pd;
+       }
+ 
+       ppgtt->vm.bind_async_flags = I915_VMA_LOCAL_BIND;
+       ppgtt->vm.insert_entries = gen8_ppgtt_insert;
+       ppgtt->vm.allocate_va_range = gen8_ppgtt_alloc;
+       ppgtt->vm.clear_range = gen8_ppgtt_clear;
+ 
+       if (intel_vgpu_active(gt->i915))
+               gen8_ppgtt_notify_vgt(ppgtt, true);
+ 
+       ppgtt->vm.cleanup = gen8_ppgtt_cleanup;
+ 
+       return ppgtt;
+ 
+ err_free_pd:
+       __gen8_ppgtt_cleanup(&ppgtt->vm, ppgtt->pd,
+                            gen8_pd_top_count(&ppgtt->vm), ppgtt->vm.top);
+ err_free_scratch:
+       free_scratch(&ppgtt->vm);
+ err_free:
+       kfree(ppgtt);
+       return ERR_PTR(err);
+ }
 
--- /dev/null
 -              ggtt->gsm = ioremap_nocache(phys_addr, size);
+ // SPDX-License-Identifier: MIT
+ /*
+  * Copyright Â© 2020 Intel Corporation
+  */
+ 
+ #include <linux/stop_machine.h>
+ 
+ #include <asm/set_memory.h>
+ #include <asm/smp.h>
+ 
+ #include "intel_gt.h"
+ #include "i915_drv.h"
+ #include "i915_scatterlist.h"
+ #include "i915_vgpu.h"
+ 
+ #include "intel_gtt.h"
+ 
+ static int
+ i915_get_ggtt_vma_pages(struct i915_vma *vma);
+ 
+ static void i915_ggtt_color_adjust(const struct drm_mm_node *node,
+                                  unsigned long color,
+                                  u64 *start,
+                                  u64 *end)
+ {
+       if (i915_node_color_differs(node, color))
+               *start += I915_GTT_PAGE_SIZE;
+ 
+       /*
+        * Also leave a space between the unallocated reserved node after the
+        * GTT and any objects within the GTT, i.e. we use the color adjustment
+        * to insert a guard page to prevent prefetches crossing over the
+        * GTT boundary.
+        */
+       node = list_next_entry(node, node_list);
+       if (node->color != color)
+               *end -= I915_GTT_PAGE_SIZE;
+ }
+ 
+ static int ggtt_init_hw(struct i915_ggtt *ggtt)
+ {
+       struct drm_i915_private *i915 = ggtt->vm.i915;
+ 
+       i915_address_space_init(&ggtt->vm, VM_CLASS_GGTT);
+ 
+       ggtt->vm.is_ggtt = true;
+ 
+       /* Only VLV supports read-only GGTT mappings */
+       ggtt->vm.has_read_only = IS_VALLEYVIEW(i915);
+ 
+       if (!HAS_LLC(i915) && !HAS_PPGTT(i915))
+               ggtt->vm.mm.color_adjust = i915_ggtt_color_adjust;
+ 
+       if (ggtt->mappable_end) {
+               if (!io_mapping_init_wc(&ggtt->iomap,
+                                       ggtt->gmadr.start,
+                                       ggtt->mappable_end)) {
+                       ggtt->vm.cleanup(&ggtt->vm);
+                       return -EIO;
+               }
+ 
+               ggtt->mtrr = arch_phys_wc_add(ggtt->gmadr.start,
+                                             ggtt->mappable_end);
+       }
+ 
+       i915_ggtt_init_fences(ggtt);
+ 
+       return 0;
+ }
+ 
+ /**
+  * i915_ggtt_init_hw - Initialize GGTT hardware
+  * @i915: i915 device
+  */
+ int i915_ggtt_init_hw(struct drm_i915_private *i915)
+ {
+       int ret;
+ 
+       stash_init(&i915->mm.wc_stash);
+ 
+       /*
+        * Note that we use page colouring to enforce a guard page at the
+        * end of the address space. This is required as the CS may prefetch
+        * beyond the end of the batch buffer, across the page boundary,
+        * and beyond the end of the GTT if we do not provide a guard.
+        */
+       ret = ggtt_init_hw(&i915->ggtt);
+       if (ret)
+               return ret;
+ 
+       return 0;
+ }
+ 
+ /*
+  * Certain Gen5 chipsets require require idling the GPU before
+  * unmapping anything from the GTT when VT-d is enabled.
+  */
+ static bool needs_idle_maps(struct drm_i915_private *i915)
+ {
+       /*
+        * Query intel_iommu to see if we need the workaround. Presumably that
+        * was loaded first.
+        */
+       return IS_GEN(i915, 5) && IS_MOBILE(i915) && intel_vtd_active();
+ }
+ 
+ static void ggtt_suspend_mappings(struct i915_ggtt *ggtt)
+ {
+       struct drm_i915_private *i915 = ggtt->vm.i915;
+ 
+       /*
+        * Don't bother messing with faults pre GEN6 as we have little
+        * documentation supporting that it's a good idea.
+        */
+       if (INTEL_GEN(i915) < 6)
+               return;
+ 
+       intel_gt_check_and_clear_faults(ggtt->vm.gt);
+ 
+       ggtt->vm.clear_range(&ggtt->vm, 0, ggtt->vm.total);
+ 
+       ggtt->invalidate(ggtt);
+ }
+ 
+ void i915_gem_suspend_gtt_mappings(struct drm_i915_private *i915)
+ {
+       ggtt_suspend_mappings(&i915->ggtt);
+ }
+ 
+ void gen6_ggtt_invalidate(struct i915_ggtt *ggtt)
+ {
+       struct intel_uncore *uncore = ggtt->vm.gt->uncore;
+ 
+       spin_lock_irq(&uncore->lock);
+       intel_uncore_write_fw(uncore, GFX_FLSH_CNTL_GEN6, GFX_FLSH_CNTL_EN);
+       intel_uncore_read_fw(uncore, GFX_FLSH_CNTL_GEN6);
+       spin_unlock_irq(&uncore->lock);
+ }
+ 
+ static void gen8_ggtt_invalidate(struct i915_ggtt *ggtt)
+ {
+       struct intel_uncore *uncore = ggtt->vm.gt->uncore;
+ 
+       /*
+        * Note that as an uncached mmio write, this will flush the
+        * WCB of the writes into the GGTT before it triggers the invalidate.
+        */
+       intel_uncore_write_fw(uncore, GFX_FLSH_CNTL_GEN6, GFX_FLSH_CNTL_EN);
+ }
+ 
+ static void guc_ggtt_invalidate(struct i915_ggtt *ggtt)
+ {
+       struct intel_uncore *uncore = ggtt->vm.gt->uncore;
+       struct drm_i915_private *i915 = ggtt->vm.i915;
+ 
+       gen8_ggtt_invalidate(ggtt);
+ 
+       if (INTEL_GEN(i915) >= 12)
+               intel_uncore_write_fw(uncore, GEN12_GUC_TLB_INV_CR,
+                                     GEN12_GUC_TLB_INV_CR_INVALIDATE);
+       else
+               intel_uncore_write_fw(uncore, GEN8_GTCR, GEN8_GTCR_INVALIDATE);
+ }
+ 
+ static void gmch_ggtt_invalidate(struct i915_ggtt *ggtt)
+ {
+       intel_gtt_chipset_flush();
+ }
+ 
+ static void gen8_set_pte(void __iomem *addr, gen8_pte_t pte)
+ {
+       writeq(pte, addr);
+ }
+ 
+ static void gen8_ggtt_insert_page(struct i915_address_space *vm,
+                                 dma_addr_t addr,
+                                 u64 offset,
+                                 enum i915_cache_level level,
+                                 u32 unused)
+ {
+       struct i915_ggtt *ggtt = i915_vm_to_ggtt(vm);
+       gen8_pte_t __iomem *pte =
+               (gen8_pte_t __iomem *)ggtt->gsm + offset / I915_GTT_PAGE_SIZE;
+ 
+       gen8_set_pte(pte, gen8_pte_encode(addr, level, 0));
+ 
+       ggtt->invalidate(ggtt);
+ }
+ 
+ static void gen8_ggtt_insert_entries(struct i915_address_space *vm,
+                                    struct i915_vma *vma,
+                                    enum i915_cache_level level,
+                                    u32 flags)
+ {
+       struct i915_ggtt *ggtt = i915_vm_to_ggtt(vm);
+       struct sgt_iter sgt_iter;
+       gen8_pte_t __iomem *gtt_entries;
+       const gen8_pte_t pte_encode = gen8_pte_encode(0, level, 0);
+       dma_addr_t addr;
+ 
+       /*
+        * Note that we ignore PTE_READ_ONLY here. The caller must be careful
+        * not to allow the user to override access to a read only page.
+        */
+ 
+       gtt_entries = (gen8_pte_t __iomem *)ggtt->gsm;
+       gtt_entries += vma->node.start / I915_GTT_PAGE_SIZE;
+       for_each_sgt_daddr(addr, sgt_iter, vma->pages)
+               gen8_set_pte(gtt_entries++, pte_encode | addr);
+ 
+       /*
+        * We want to flush the TLBs only after we're certain all the PTE
+        * updates have finished.
+        */
+       ggtt->invalidate(ggtt);
+ }
+ 
+ static void gen6_ggtt_insert_page(struct i915_address_space *vm,
+                                 dma_addr_t addr,
+                                 u64 offset,
+                                 enum i915_cache_level level,
+                                 u32 flags)
+ {
+       struct i915_ggtt *ggtt = i915_vm_to_ggtt(vm);
+       gen6_pte_t __iomem *pte =
+               (gen6_pte_t __iomem *)ggtt->gsm + offset / I915_GTT_PAGE_SIZE;
+ 
+       iowrite32(vm->pte_encode(addr, level, flags), pte);
+ 
+       ggtt->invalidate(ggtt);
+ }
+ 
+ /*
+  * Binds an object into the global gtt with the specified cache level.
+  * The object will be accessible to the GPU via commands whose operands
+  * reference offsets within the global GTT as well as accessible by the GPU
+  * through the GMADR mapped BAR (i915->mm.gtt->gtt).
+  */
+ static void gen6_ggtt_insert_entries(struct i915_address_space *vm,
+                                    struct i915_vma *vma,
+                                    enum i915_cache_level level,
+                                    u32 flags)
+ {
+       struct i915_ggtt *ggtt = i915_vm_to_ggtt(vm);
+       gen6_pte_t __iomem *entries = (gen6_pte_t __iomem *)ggtt->gsm;
+       unsigned int i = vma->node.start / I915_GTT_PAGE_SIZE;
+       struct sgt_iter iter;
+       dma_addr_t addr;
+ 
+       for_each_sgt_daddr(addr, iter, vma->pages)
+               iowrite32(vm->pte_encode(addr, level, flags), &entries[i++]);
+ 
+       /*
+        * We want to flush the TLBs only after we're certain all the PTE
+        * updates have finished.
+        */
+       ggtt->invalidate(ggtt);
+ }
+ 
+ static void nop_clear_range(struct i915_address_space *vm,
+                           u64 start, u64 length)
+ {
+ }
+ 
+ static void gen8_ggtt_clear_range(struct i915_address_space *vm,
+                                 u64 start, u64 length)
+ {
+       struct i915_ggtt *ggtt = i915_vm_to_ggtt(vm);
+       unsigned int first_entry = start / I915_GTT_PAGE_SIZE;
+       unsigned int num_entries = length / I915_GTT_PAGE_SIZE;
+       const gen8_pte_t scratch_pte = vm->scratch[0].encode;
+       gen8_pte_t __iomem *gtt_base =
+               (gen8_pte_t __iomem *)ggtt->gsm + first_entry;
+       const int max_entries = ggtt_total_entries(ggtt) - first_entry;
+       int i;
+ 
+       if (WARN(num_entries > max_entries,
+                "First entry = %d; Num entries = %d (max=%d)\n",
+                first_entry, num_entries, max_entries))
+               num_entries = max_entries;
+ 
+       for (i = 0; i < num_entries; i++)
+               gen8_set_pte(>t_base[i], scratch_pte);
+ }
+ 
+ static void bxt_vtd_ggtt_wa(struct i915_address_space *vm)
+ {
+       /*
+        * Make sure the internal GAM fifo has been cleared of all GTT
+        * writes before exiting stop_machine(). This guarantees that
+        * any aperture accesses waiting to start in another process
+        * cannot back up behind the GTT writes causing a hang.
+        * The register can be any arbitrary GAM register.
+        */
+       intel_uncore_posting_read_fw(vm->gt->uncore, GFX_FLSH_CNTL_GEN6);
+ }
+ 
+ struct insert_page {
+       struct i915_address_space *vm;
+       dma_addr_t addr;
+       u64 offset;
+       enum i915_cache_level level;
+ };
+ 
+ static int bxt_vtd_ggtt_insert_page__cb(void *_arg)
+ {
+       struct insert_page *arg = _arg;
+ 
+       gen8_ggtt_insert_page(arg->vm, arg->addr, arg->offset, arg->level, 0);
+       bxt_vtd_ggtt_wa(arg->vm);
+ 
+       return 0;
+ }
+ 
+ static void bxt_vtd_ggtt_insert_page__BKL(struct i915_address_space *vm,
+                                         dma_addr_t addr,
+                                         u64 offset,
+                                         enum i915_cache_level level,
+                                         u32 unused)
+ {
+       struct insert_page arg = { vm, addr, offset, level };
+ 
+       stop_machine(bxt_vtd_ggtt_insert_page__cb, &arg, NULL);
+ }
+ 
+ struct insert_entries {
+       struct i915_address_space *vm;
+       struct i915_vma *vma;
+       enum i915_cache_level level;
+       u32 flags;
+ };
+ 
+ static int bxt_vtd_ggtt_insert_entries__cb(void *_arg)
+ {
+       struct insert_entries *arg = _arg;
+ 
+       gen8_ggtt_insert_entries(arg->vm, arg->vma, arg->level, arg->flags);
+       bxt_vtd_ggtt_wa(arg->vm);
+ 
+       return 0;
+ }
+ 
+ static void bxt_vtd_ggtt_insert_entries__BKL(struct i915_address_space *vm,
+                                            struct i915_vma *vma,
+                                            enum i915_cache_level level,
+                                            u32 flags)
+ {
+       struct insert_entries arg = { vm, vma, level, flags };
+ 
+       stop_machine(bxt_vtd_ggtt_insert_entries__cb, &arg, NULL);
+ }
+ 
+ struct clear_range {
+       struct i915_address_space *vm;
+       u64 start;
+       u64 length;
+ };
+ 
+ static int bxt_vtd_ggtt_clear_range__cb(void *_arg)
+ {
+       struct clear_range *arg = _arg;
+ 
+       gen8_ggtt_clear_range(arg->vm, arg->start, arg->length);
+       bxt_vtd_ggtt_wa(arg->vm);
+ 
+       return 0;
+ }
+ 
+ static void bxt_vtd_ggtt_clear_range__BKL(struct i915_address_space *vm,
+                                         u64 start,
+                                         u64 length)
+ {
+       struct clear_range arg = { vm, start, length };
+ 
+       stop_machine(bxt_vtd_ggtt_clear_range__cb, &arg, NULL);
+ }
+ 
+ static void gen6_ggtt_clear_range(struct i915_address_space *vm,
+                                 u64 start, u64 length)
+ {
+       struct i915_ggtt *ggtt = i915_vm_to_ggtt(vm);
+       unsigned int first_entry = start / I915_GTT_PAGE_SIZE;
+       unsigned int num_entries = length / I915_GTT_PAGE_SIZE;
+       gen6_pte_t scratch_pte, __iomem *gtt_base =
+               (gen6_pte_t __iomem *)ggtt->gsm + first_entry;
+       const int max_entries = ggtt_total_entries(ggtt) - first_entry;
+       int i;
+ 
+       if (WARN(num_entries > max_entries,
+                "First entry = %d; Num entries = %d (max=%d)\n",
+                first_entry, num_entries, max_entries))
+               num_entries = max_entries;
+ 
+       scratch_pte = vm->scratch[0].encode;
+       for (i = 0; i < num_entries; i++)
+               iowrite32(scratch_pte, >t_base[i]);
+ }
+ 
+ static void i915_ggtt_insert_page(struct i915_address_space *vm,
+                                 dma_addr_t addr,
+                                 u64 offset,
+                                 enum i915_cache_level cache_level,
+                                 u32 unused)
+ {
+       unsigned int flags = (cache_level == I915_CACHE_NONE) ?
+               AGP_USER_MEMORY : AGP_USER_CACHED_MEMORY;
+ 
+       intel_gtt_insert_page(addr, offset >> PAGE_SHIFT, flags);
+ }
+ 
+ static void i915_ggtt_insert_entries(struct i915_address_space *vm,
+                                    struct i915_vma *vma,
+                                    enum i915_cache_level cache_level,
+                                    u32 unused)
+ {
+       unsigned int flags = (cache_level == I915_CACHE_NONE) ?
+               AGP_USER_MEMORY : AGP_USER_CACHED_MEMORY;
+ 
+       intel_gtt_insert_sg_entries(vma->pages, vma->node.start >> PAGE_SHIFT,
+                                   flags);
+ }
+ 
+ static void i915_ggtt_clear_range(struct i915_address_space *vm,
+                                 u64 start, u64 length)
+ {
+       intel_gtt_clear_range(start >> PAGE_SHIFT, length >> PAGE_SHIFT);
+ }
+ 
+ static int ggtt_bind_vma(struct i915_vma *vma,
+                        enum i915_cache_level cache_level,
+                        u32 flags)
+ {
+       struct drm_i915_gem_object *obj = vma->obj;
+       u32 pte_flags;
+ 
+       /* Applicable to VLV (gen8+ do not support RO in the GGTT) */
+       pte_flags = 0;
+       if (i915_gem_object_is_readonly(obj))
+               pte_flags |= PTE_READ_ONLY;
+ 
+       vma->vm->insert_entries(vma->vm, vma, cache_level, pte_flags);
+ 
+       vma->page_sizes.gtt = I915_GTT_PAGE_SIZE;
+ 
+       /*
+        * Without aliasing PPGTT there's no difference between
+        * GLOBAL/LOCAL_BIND, it's all the same ptes. Hence unconditionally
+        * upgrade to both bound if we bind either to avoid double-binding.
+        */
+       atomic_or(I915_VMA_GLOBAL_BIND | I915_VMA_LOCAL_BIND, &vma->flags);
+ 
+       return 0;
+ }
+ 
+ static void ggtt_unbind_vma(struct i915_vma *vma)
+ {
+       vma->vm->clear_range(vma->vm, vma->node.start, vma->size);
+ }
+ 
+ static int ggtt_reserve_guc_top(struct i915_ggtt *ggtt)
+ {
+       u64 size;
+       int ret;
+ 
+       if (!USES_GUC(ggtt->vm.i915))
+               return 0;
+ 
+       GEM_BUG_ON(ggtt->vm.total <= GUC_GGTT_TOP);
+       size = ggtt->vm.total - GUC_GGTT_TOP;
+ 
+       ret = i915_gem_gtt_reserve(&ggtt->vm, &ggtt->uc_fw, size,
+                                  GUC_GGTT_TOP, I915_COLOR_UNEVICTABLE,
+                                  PIN_NOEVICT);
+       if (ret)
+               DRM_DEBUG_DRIVER("Failed to reserve top of GGTT for GuC\n");
+ 
+       return ret;
+ }
+ 
+ static void ggtt_release_guc_top(struct i915_ggtt *ggtt)
+ {
+       if (drm_mm_node_allocated(&ggtt->uc_fw))
+               drm_mm_remove_node(&ggtt->uc_fw);
+ }
+ 
+ static void cleanup_init_ggtt(struct i915_ggtt *ggtt)
+ {
+       ggtt_release_guc_top(ggtt);
+       if (drm_mm_node_allocated(&ggtt->error_capture))
+               drm_mm_remove_node(&ggtt->error_capture);
+       mutex_destroy(&ggtt->error_mutex);
+ }
+ 
+ static int init_ggtt(struct i915_ggtt *ggtt)
+ {
+       /*
+        * Let GEM Manage all of the aperture.
+        *
+        * However, leave one page at the end still bound to the scratch page.
+        * There are a number of places where the hardware apparently prefetches
+        * past the end of the object, and we've seen multiple hangs with the
+        * GPU head pointer stuck in a batchbuffer bound at the last page of the
+        * aperture.  One page should be enough to keep any prefetching inside
+        * of the aperture.
+        */
+       unsigned long hole_start, hole_end;
+       struct drm_mm_node *entry;
+       int ret;
+ 
+       /*
+        * GuC requires all resources that we're sharing with it to be placed in
+        * non-WOPCM memory. If GuC is not present or not in use we still need a
+        * small bias as ring wraparound at offset 0 sometimes hangs. No idea
+        * why.
+        */
+       ggtt->pin_bias = max_t(u32, I915_GTT_PAGE_SIZE,
+                              intel_wopcm_guc_size(&ggtt->vm.i915->wopcm));
+ 
+       ret = intel_vgt_balloon(ggtt);
+       if (ret)
+               return ret;
+ 
+       mutex_init(&ggtt->error_mutex);
+       if (ggtt->mappable_end) {
+               /* Reserve a mappable slot for our lockless error capture */
+               ret = drm_mm_insert_node_in_range(&ggtt->vm.mm,
+                                                 &ggtt->error_capture,
+                                                 PAGE_SIZE, 0,
+                                                 I915_COLOR_UNEVICTABLE,
+                                                 0, ggtt->mappable_end,
+                                                 DRM_MM_INSERT_LOW);
+               if (ret)
+                       return ret;
+       }
+ 
+       /*
+        * The upper portion of the GuC address space has a sizeable hole
+        * (several MB) that is inaccessible by GuC. Reserve this range within
+        * GGTT as it can comfortably hold GuC/HuC firmware images.
+        */
+       ret = ggtt_reserve_guc_top(ggtt);
+       if (ret)
+               goto err;
+ 
+       /* Clear any non-preallocated blocks */
+       drm_mm_for_each_hole(entry, &ggtt->vm.mm, hole_start, hole_end) {
+               DRM_DEBUG_KMS("clearing unused GTT space: [%lx, %lx]\n",
+                             hole_start, hole_end);
+               ggtt->vm.clear_range(&ggtt->vm, hole_start,
+                                    hole_end - hole_start);
+       }
+ 
+       /* And finally clear the reserved guard page */
+       ggtt->vm.clear_range(&ggtt->vm, ggtt->vm.total - PAGE_SIZE, PAGE_SIZE);
+ 
+       return 0;
+ 
+ err:
+       cleanup_init_ggtt(ggtt);
+       return ret;
+ }
+ 
+ static int aliasing_gtt_bind_vma(struct i915_vma *vma,
+                                enum i915_cache_level cache_level,
+                                u32 flags)
+ {
+       u32 pte_flags;
+       int ret;
+ 
+       /* Currently applicable only to VLV */
+       pte_flags = 0;
+       if (i915_gem_object_is_readonly(vma->obj))
+               pte_flags |= PTE_READ_ONLY;
+ 
+       if (flags & I915_VMA_LOCAL_BIND) {
+               struct i915_ppgtt *alias = i915_vm_to_ggtt(vma->vm)->alias;
+ 
+               if (flags & I915_VMA_ALLOC) {
+                       ret = alias->vm.allocate_va_range(&alias->vm,
+                                                         vma->node.start,
+                                                         vma->size);
+                       if (ret)
+                               return ret;
+ 
+                       set_bit(I915_VMA_ALLOC_BIT, __i915_vma_flags(vma));
+               }
+ 
+               GEM_BUG_ON(!test_bit(I915_VMA_ALLOC_BIT,
+                                    __i915_vma_flags(vma)));
+               alias->vm.insert_entries(&alias->vm, vma,
+                                        cache_level, pte_flags);
+       }
+ 
+       if (flags & I915_VMA_GLOBAL_BIND)
+               vma->vm->insert_entries(vma->vm, vma, cache_level, pte_flags);
+ 
+       return 0;
+ }
+ 
+ static void aliasing_gtt_unbind_vma(struct i915_vma *vma)
+ {
+       if (i915_vma_is_bound(vma, I915_VMA_GLOBAL_BIND)) {
+               struct i915_address_space *vm = vma->vm;
+ 
+               vm->clear_range(vm, vma->node.start, vma->size);
+       }
+ 
+       if (test_and_clear_bit(I915_VMA_ALLOC_BIT, __i915_vma_flags(vma))) {
+               struct i915_address_space *vm =
+                       &i915_vm_to_ggtt(vma->vm)->alias->vm;
+ 
+               vm->clear_range(vm, vma->node.start, vma->size);
+       }
+ }
+ 
+ static int init_aliasing_ppgtt(struct i915_ggtt *ggtt)
+ {
+       struct i915_ppgtt *ppgtt;
+       int err;
+ 
+       ppgtt = i915_ppgtt_create(ggtt->vm.gt);
+       if (IS_ERR(ppgtt))
+               return PTR_ERR(ppgtt);
+ 
+       if (GEM_WARN_ON(ppgtt->vm.total < ggtt->vm.total)) {
+               err = -ENODEV;
+               goto err_ppgtt;
+       }
+ 
+       /*
+        * Note we only pre-allocate as far as the end of the global
+        * GTT. On 48b / 4-level page-tables, the difference is very,
+        * very significant! We have to preallocate as GVT/vgpu does
+        * not like the page directory disappearing.
+        */
+       err = ppgtt->vm.allocate_va_range(&ppgtt->vm, 0, ggtt->vm.total);
+       if (err)
+               goto err_ppgtt;
+ 
+       ggtt->alias = ppgtt;
+       ggtt->vm.bind_async_flags |= ppgtt->vm.bind_async_flags;
+ 
+       GEM_BUG_ON(ggtt->vm.vma_ops.bind_vma != ggtt_bind_vma);
+       ggtt->vm.vma_ops.bind_vma = aliasing_gtt_bind_vma;
+ 
+       GEM_BUG_ON(ggtt->vm.vma_ops.unbind_vma != ggtt_unbind_vma);
+       ggtt->vm.vma_ops.unbind_vma = aliasing_gtt_unbind_vma;
+ 
+       return 0;
+ 
+ err_ppgtt:
+       i915_vm_put(&ppgtt->vm);
+       return err;
+ }
+ 
+ static void fini_aliasing_ppgtt(struct i915_ggtt *ggtt)
+ {
+       struct i915_ppgtt *ppgtt;
+ 
+       ppgtt = fetch_and_zero(&ggtt->alias);
+       if (!ppgtt)
+               return;
+ 
+       i915_vm_put(&ppgtt->vm);
+ 
+       ggtt->vm.vma_ops.bind_vma   = ggtt_bind_vma;
+       ggtt->vm.vma_ops.unbind_vma = ggtt_unbind_vma;
+ }
+ 
+ int i915_init_ggtt(struct drm_i915_private *i915)
+ {
+       int ret;
+ 
+       ret = init_ggtt(&i915->ggtt);
+       if (ret)
+               return ret;
+ 
+       if (INTEL_PPGTT(i915) == INTEL_PPGTT_ALIASING) {
+               ret = init_aliasing_ppgtt(&i915->ggtt);
+               if (ret)
+                       cleanup_init_ggtt(&i915->ggtt);
+       }
+ 
+       return 0;
+ }
+ 
+ static void ggtt_cleanup_hw(struct i915_ggtt *ggtt)
+ {
+       struct i915_vma *vma, *vn;
+ 
+       atomic_set(&ggtt->vm.open, 0);
+ 
+       rcu_barrier(); /* flush the RCU'ed__i915_vm_release */
+       flush_workqueue(ggtt->vm.i915->wq);
+ 
+       mutex_lock(&ggtt->vm.mutex);
+ 
+       list_for_each_entry_safe(vma, vn, &ggtt->vm.bound_list, vm_link)
+               WARN_ON(__i915_vma_unbind(vma));
+ 
+       if (drm_mm_node_allocated(&ggtt->error_capture))
+               drm_mm_remove_node(&ggtt->error_capture);
+       mutex_destroy(&ggtt->error_mutex);
+ 
+       ggtt_release_guc_top(ggtt);
+       intel_vgt_deballoon(ggtt);
+ 
+       ggtt->vm.cleanup(&ggtt->vm);
+ 
+       mutex_unlock(&ggtt->vm.mutex);
+       i915_address_space_fini(&ggtt->vm);
+ 
+       arch_phys_wc_del(ggtt->mtrr);
+ 
+       if (ggtt->iomap.size)
+               io_mapping_fini(&ggtt->iomap);
+ }
+ 
+ /**
+  * i915_ggtt_driver_release - Clean up GGTT hardware initialization
+  * @i915: i915 device
+  */
+ void i915_ggtt_driver_release(struct drm_i915_private *i915)
+ {
+       struct pagevec *pvec;
+ 
+       fini_aliasing_ppgtt(&i915->ggtt);
+ 
+       ggtt_cleanup_hw(&i915->ggtt);
+ 
+       pvec = &i915->mm.wc_stash.pvec;
+       if (pvec->nr) {
+               set_pages_array_wb(pvec->pages, pvec->nr);
+               __pagevec_release(pvec);
+       }
+ }
+ 
+ static unsigned int gen6_get_total_gtt_size(u16 snb_gmch_ctl)
+ {
+       snb_gmch_ctl >>= SNB_GMCH_GGMS_SHIFT;
+       snb_gmch_ctl &= SNB_GMCH_GGMS_MASK;
+       return snb_gmch_ctl << 20;
+ }
+ 
+ static unsigned int gen8_get_total_gtt_size(u16 bdw_gmch_ctl)
+ {
+       bdw_gmch_ctl >>= BDW_GMCH_GGMS_SHIFT;
+       bdw_gmch_ctl &= BDW_GMCH_GGMS_MASK;
+       if (bdw_gmch_ctl)
+               bdw_gmch_ctl = 1 << bdw_gmch_ctl;
+ 
+ #ifdef CONFIG_X86_32
+       /* Limit 32b platforms to a 2GB GGTT: 4 << 20 / pte size * I915_GTT_PAGE_SIZE */
+       if (bdw_gmch_ctl > 4)
+               bdw_gmch_ctl = 4;
+ #endif
+ 
+       return bdw_gmch_ctl << 20;
+ }
+ 
+ static unsigned int chv_get_total_gtt_size(u16 gmch_ctrl)
+ {
+       gmch_ctrl >>= SNB_GMCH_GGMS_SHIFT;
+       gmch_ctrl &= SNB_GMCH_GGMS_MASK;
+ 
+       if (gmch_ctrl)
+               return 1 << (20 + gmch_ctrl);
+ 
+       return 0;
+ }
+ 
+ static int ggtt_probe_common(struct i915_ggtt *ggtt, u64 size)
+ {
+       struct drm_i915_private *i915 = ggtt->vm.i915;
+       struct pci_dev *pdev = i915->drm.pdev;
+       phys_addr_t phys_addr;
+       int ret;
+ 
+       /* For Modern GENs the PTEs and register space are split in the BAR */
+       phys_addr = pci_resource_start(pdev, 0) + pci_resource_len(pdev, 0) / 2;
+ 
+       /*
+        * On BXT+/CNL+ writes larger than 64 bit to the GTT pagetable range
+        * will be dropped. For WC mappings in general we have 64 byte burst
+        * writes when the WC buffer is flushed, so we can't use it, but have to
+        * resort to an uncached mapping. The WC issue is easily caught by the
+        * readback check when writing GTT PTE entries.
+        */
+       if (IS_GEN9_LP(i915) || INTEL_GEN(i915) >= 10)
++              ggtt->gsm = ioremap(phys_addr, size);
+       else
+               ggtt->gsm = ioremap_wc(phys_addr, size);
+       if (!ggtt->gsm) {
+               DRM_ERROR("Failed to map the ggtt page table\n");
+               return -ENOMEM;
+       }
+ 
+       ret = setup_scratch_page(&ggtt->vm, GFP_DMA32);
+       if (ret) {
+               DRM_ERROR("Scratch setup failed\n");
+               /* iounmap will also get called at remove, but meh */
+               iounmap(ggtt->gsm);
+               return ret;
+       }
+ 
+       ggtt->vm.scratch[0].encode =
+               ggtt->vm.pte_encode(px_dma(&ggtt->vm.scratch[0]),
+                                   I915_CACHE_NONE, 0);
+ 
+       return 0;
+ }
+ 
+ int ggtt_set_pages(struct i915_vma *vma)
+ {
+       int ret;
+ 
+       GEM_BUG_ON(vma->pages);
+ 
+       ret = i915_get_ggtt_vma_pages(vma);
+       if (ret)
+               return ret;
+ 
+       vma->page_sizes = vma->obj->mm.page_sizes;
+ 
+       return 0;
+ }
+ 
+ static void gen6_gmch_remove(struct i915_address_space *vm)
+ {
+       struct i915_ggtt *ggtt = i915_vm_to_ggtt(vm);
+ 
+       iounmap(ggtt->gsm);
+       cleanup_scratch_page(vm);
+ }
+ 
+ static struct resource pci_resource(struct pci_dev *pdev, int bar)
+ {
+       return (struct resource)DEFINE_RES_MEM(pci_resource_start(pdev, bar),
+                                              pci_resource_len(pdev, bar));
+ }
+ 
+ static int gen8_gmch_probe(struct i915_ggtt *ggtt)
+ {
+       struct drm_i915_private *i915 = ggtt->vm.i915;
+       struct pci_dev *pdev = i915->drm.pdev;
+       unsigned int size;
+       u16 snb_gmch_ctl;
+       int err;
+ 
+       /* TODO: We're not aware of mappable constraints on gen8 yet */
+       if (!IS_DGFX(i915)) {
+               ggtt->gmadr = pci_resource(pdev, 2);
+               ggtt->mappable_end = resource_size(&ggtt->gmadr);
+       }
+ 
+       err = pci_set_dma_mask(pdev, DMA_BIT_MASK(39));
+       if (!err)
+               err = pci_set_consistent_dma_mask(pdev, DMA_BIT_MASK(39));
+       if (err)
+               DRM_ERROR("Can't set DMA mask/consistent mask (%d)\n", err);
+ 
+       pci_read_config_word(pdev, SNB_GMCH_CTRL, &snb_gmch_ctl);
+       if (IS_CHERRYVIEW(i915))
+               size = chv_get_total_gtt_size(snb_gmch_ctl);
+       else
+               size = gen8_get_total_gtt_size(snb_gmch_ctl);
+ 
+       ggtt->vm.total = (size / sizeof(gen8_pte_t)) * I915_GTT_PAGE_SIZE;
+       ggtt->vm.cleanup = gen6_gmch_remove;
+       ggtt->vm.insert_page = gen8_ggtt_insert_page;
+       ggtt->vm.clear_range = nop_clear_range;
+       if (intel_scanout_needs_vtd_wa(i915))
+               ggtt->vm.clear_range = gen8_ggtt_clear_range;
+ 
+       ggtt->vm.insert_entries = gen8_ggtt_insert_entries;
+ 
+       /* Serialize GTT updates with aperture access on BXT if VT-d is on. */
+       if (intel_ggtt_update_needs_vtd_wa(i915) ||
+           IS_CHERRYVIEW(i915) /* fails with concurrent use/update */) {
+               ggtt->vm.insert_entries = bxt_vtd_ggtt_insert_entries__BKL;
+               ggtt->vm.insert_page    = bxt_vtd_ggtt_insert_page__BKL;
+               if (ggtt->vm.clear_range != nop_clear_range)
+                       ggtt->vm.clear_range = bxt_vtd_ggtt_clear_range__BKL;
+       }
+ 
+       ggtt->invalidate = gen8_ggtt_invalidate;
+ 
+       ggtt->vm.vma_ops.bind_vma    = ggtt_bind_vma;
+       ggtt->vm.vma_ops.unbind_vma  = ggtt_unbind_vma;
+       ggtt->vm.vma_ops.set_pages   = ggtt_set_pages;
+       ggtt->vm.vma_ops.clear_pages = clear_pages;
+ 
+       ggtt->vm.pte_encode = gen8_pte_encode;
+ 
+       setup_private_pat(ggtt->vm.gt->uncore);
+ 
+       return ggtt_probe_common(ggtt, size);
+ }
+ 
+ static u64 snb_pte_encode(dma_addr_t addr,
+                         enum i915_cache_level level,
+                         u32 flags)
+ {
+       gen6_pte_t pte = GEN6_PTE_ADDR_ENCODE(addr) | GEN6_PTE_VALID;
+ 
+       switch (level) {
+       case I915_CACHE_L3_LLC:
+       case I915_CACHE_LLC:
+               pte |= GEN6_PTE_CACHE_LLC;
+               break;
+       case I915_CACHE_NONE:
+               pte |= GEN6_PTE_UNCACHED;
+               break;
+       default:
+               MISSING_CASE(level);
+       }
+ 
+       return pte;
+ }
+ 
+ static u64 ivb_pte_encode(dma_addr_t addr,
+                         enum i915_cache_level level,
+                         u32 flags)
+ {
+       gen6_pte_t pte = GEN6_PTE_ADDR_ENCODE(addr) | GEN6_PTE_VALID;
+ 
+       switch (level) {
+       case I915_CACHE_L3_LLC:
+               pte |= GEN7_PTE_CACHE_L3_LLC;
+               break;
+       case I915_CACHE_LLC:
+               pte |= GEN6_PTE_CACHE_LLC;
+               break;
+       case I915_CACHE_NONE:
+               pte |= GEN6_PTE_UNCACHED;
+               break;
+       default:
+               MISSING_CASE(level);
+       }
+ 
+       return pte;
+ }
+ 
+ static u64 byt_pte_encode(dma_addr_t addr,
+                         enum i915_cache_level level,
+                         u32 flags)
+ {
+       gen6_pte_t pte = GEN6_PTE_ADDR_ENCODE(addr) | GEN6_PTE_VALID;
+ 
+       if (!(flags & PTE_READ_ONLY))
+               pte |= BYT_PTE_WRITEABLE;
+ 
+       if (level != I915_CACHE_NONE)
+               pte |= BYT_PTE_SNOOPED_BY_CPU_CACHES;
+ 
+       return pte;
+ }
+ 
+ static u64 hsw_pte_encode(dma_addr_t addr,
+                         enum i915_cache_level level,
+                         u32 flags)
+ {
+       gen6_pte_t pte = HSW_PTE_ADDR_ENCODE(addr) | GEN6_PTE_VALID;
+ 
+       if (level != I915_CACHE_NONE)
+               pte |= HSW_WB_LLC_AGE3;
+ 
+       return pte;
+ }
+ 
+ static u64 iris_pte_encode(dma_addr_t addr,
+                          enum i915_cache_level level,
+                          u32 flags)
+ {
+       gen6_pte_t pte = HSW_PTE_ADDR_ENCODE(addr) | GEN6_PTE_VALID;
+ 
+       switch (level) {
+       case I915_CACHE_NONE:
+               break;
+       case I915_CACHE_WT:
+               pte |= HSW_WT_ELLC_LLC_AGE3;
+               break;
+       default:
+               pte |= HSW_WB_ELLC_LLC_AGE3;
+               break;
+       }
+ 
+       return pte;
+ }
+ 
+ static int gen6_gmch_probe(struct i915_ggtt *ggtt)
+ {
+       struct drm_i915_private *i915 = ggtt->vm.i915;
+       struct pci_dev *pdev = i915->drm.pdev;
+       unsigned int size;
+       u16 snb_gmch_ctl;
+       int err;
+ 
+       ggtt->gmadr = pci_resource(pdev, 2);
+       ggtt->mappable_end = resource_size(&ggtt->gmadr);
+ 
+       /*
+        * 64/512MB is the current min/max we actually know of, but this is
+        * just a coarse sanity check.
+        */
+       if (ggtt->mappable_end < (64<<20) || ggtt->mappable_end > (512<<20)) {
+               DRM_ERROR("Unknown GMADR size (%pa)\n", &ggtt->mappable_end);
+               return -ENXIO;
+       }
+ 
+       err = pci_set_dma_mask(pdev, DMA_BIT_MASK(40));
+       if (!err)
+               err = pci_set_consistent_dma_mask(pdev, DMA_BIT_MASK(40));
+       if (err)
+               DRM_ERROR("Can't set DMA mask/consistent mask (%d)\n", err);
+       pci_read_config_word(pdev, SNB_GMCH_CTRL, &snb_gmch_ctl);
+ 
+       size = gen6_get_total_gtt_size(snb_gmch_ctl);
+       ggtt->vm.total = (size / sizeof(gen6_pte_t)) * I915_GTT_PAGE_SIZE;
+ 
+       ggtt->vm.clear_range = nop_clear_range;
+       if (!HAS_FULL_PPGTT(i915) || intel_scanout_needs_vtd_wa(i915))
+               ggtt->vm.clear_range = gen6_ggtt_clear_range;
+       ggtt->vm.insert_page = gen6_ggtt_insert_page;
+       ggtt->vm.insert_entries = gen6_ggtt_insert_entries;
+       ggtt->vm.cleanup = gen6_gmch_remove;
+ 
+       ggtt->invalidate = gen6_ggtt_invalidate;
+ 
+       if (HAS_EDRAM(i915))
+               ggtt->vm.pte_encode = iris_pte_encode;
+       else if (IS_HASWELL(i915))
+               ggtt->vm.pte_encode = hsw_pte_encode;
+       else if (IS_VALLEYVIEW(i915))
+               ggtt->vm.pte_encode = byt_pte_encode;
+       else if (INTEL_GEN(i915) >= 7)
+               ggtt->vm.pte_encode = ivb_pte_encode;
+       else
+               ggtt->vm.pte_encode = snb_pte_encode;
+ 
+       ggtt->vm.vma_ops.bind_vma    = ggtt_bind_vma;
+       ggtt->vm.vma_ops.unbind_vma  = ggtt_unbind_vma;
+       ggtt->vm.vma_ops.set_pages   = ggtt_set_pages;
+       ggtt->vm.vma_ops.clear_pages = clear_pages;
+ 
+       return ggtt_probe_common(ggtt, size);
+ }
+ 
+ static void i915_gmch_remove(struct i915_address_space *vm)
+ {
+       intel_gmch_remove();
+ }
+ 
+ static int i915_gmch_probe(struct i915_ggtt *ggtt)
+ {
+       struct drm_i915_private *i915 = ggtt->vm.i915;
+       phys_addr_t gmadr_base;
+       int ret;
+ 
+       ret = intel_gmch_probe(i915->bridge_dev, i915->drm.pdev, NULL);
+       if (!ret) {
+               DRM_ERROR("failed to set up gmch\n");
+               return -EIO;
+       }
+ 
+       intel_gtt_get(&ggtt->vm.total, &gmadr_base, &ggtt->mappable_end);
+ 
+       ggtt->gmadr =
+               (struct resource)DEFINE_RES_MEM(gmadr_base, ggtt->mappable_end);
+ 
+       ggtt->do_idle_maps = needs_idle_maps(i915);
+       ggtt->vm.insert_page = i915_ggtt_insert_page;
+       ggtt->vm.insert_entries = i915_ggtt_insert_entries;
+       ggtt->vm.clear_range = i915_ggtt_clear_range;
+       ggtt->vm.cleanup = i915_gmch_remove;
+ 
+       ggtt->invalidate = gmch_ggtt_invalidate;
+ 
+       ggtt->vm.vma_ops.bind_vma    = ggtt_bind_vma;
+       ggtt->vm.vma_ops.unbind_vma  = ggtt_unbind_vma;
+       ggtt->vm.vma_ops.set_pages   = ggtt_set_pages;
+       ggtt->vm.vma_ops.clear_pages = clear_pages;
+ 
+       if (unlikely(ggtt->do_idle_maps))
+               dev_notice(i915->drm.dev,
+                          "Applying Ironlake quirks for intel_iommu\n");
+ 
+       return 0;
+ }
+ 
+ static int ggtt_probe_hw(struct i915_ggtt *ggtt, struct intel_gt *gt)
+ {
+       struct drm_i915_private *i915 = gt->i915;
+       int ret;
+ 
+       ggtt->vm.gt = gt;
+       ggtt->vm.i915 = i915;
+       ggtt->vm.dma = &i915->drm.pdev->dev;
+ 
+       if (INTEL_GEN(i915) <= 5)
+               ret = i915_gmch_probe(ggtt);
+       else if (INTEL_GEN(i915) < 8)
+               ret = gen6_gmch_probe(ggtt);
+       else
+               ret = gen8_gmch_probe(ggtt);
+       if (ret)
+               return ret;
+ 
+       if ((ggtt->vm.total - 1) >> 32) {
+               DRM_ERROR("We never expected a Global GTT with more than 32bits"
+                         " of address space! Found %lldM!\n",
+                         ggtt->vm.total >> 20);
+               ggtt->vm.total = 1ULL << 32;
+               ggtt->mappable_end =
+                       min_t(u64, ggtt->mappable_end, ggtt->vm.total);
+       }
+ 
+       if (ggtt->mappable_end > ggtt->vm.total) {
+               DRM_ERROR("mappable aperture extends past end of GGTT,"
+                         " aperture=%pa, total=%llx\n",
+                         &ggtt->mappable_end, ggtt->vm.total);
+               ggtt->mappable_end = ggtt->vm.total;
+       }
+ 
+       /* GMADR is the PCI mmio aperture into the global GTT. */
+       DRM_DEBUG_DRIVER("GGTT size = %lluM\n", ggtt->vm.total >> 20);
+       DRM_DEBUG_DRIVER("GMADR size = %lluM\n", (u64)ggtt->mappable_end >> 20);
+       DRM_DEBUG_DRIVER("DSM size = %lluM\n",
+                        (u64)resource_size(&intel_graphics_stolen_res) >> 20);
+ 
+       return 0;
+ }
+ 
+ /**
+  * i915_ggtt_probe_hw - Probe GGTT hardware location
+  * @i915: i915 device
+  */
+ int i915_ggtt_probe_hw(struct drm_i915_private *i915)
+ {
+       int ret;
+ 
+       ret = ggtt_probe_hw(&i915->ggtt, &i915->gt);
+       if (ret)
+               return ret;
+ 
+       if (intel_vtd_active())
+               dev_info(i915->drm.dev, "VT-d active for gfx access\n");
+ 
+       return 0;
+ }
+ 
+ int i915_ggtt_enable_hw(struct drm_i915_private *i915)
+ {
+       if (INTEL_GEN(i915) < 6 && !intel_enable_gtt())
+               return -EIO;
+ 
+       return 0;
+ }
+ 
+ void i915_ggtt_enable_guc(struct i915_ggtt *ggtt)
+ {
+       GEM_BUG_ON(ggtt->invalidate != gen8_ggtt_invalidate);
+ 
+       ggtt->invalidate = guc_ggtt_invalidate;
+ 
+       ggtt->invalidate(ggtt);
+ }
+ 
+ void i915_ggtt_disable_guc(struct i915_ggtt *ggtt)
+ {
+       /* XXX Temporary pardon for error unload */
+       if (ggtt->invalidate == gen8_ggtt_invalidate)
+               return;
+ 
+       /* We should only be called after i915_ggtt_enable_guc() */
+       GEM_BUG_ON(ggtt->invalidate != guc_ggtt_invalidate);
+ 
+       ggtt->invalidate = gen8_ggtt_invalidate;
+ 
+       ggtt->invalidate(ggtt);
+ }
+ 
+ static void ggtt_restore_mappings(struct i915_ggtt *ggtt)
+ {
+       struct i915_vma *vma;
+       bool flush = false;
+       int open;
+ 
+       intel_gt_check_and_clear_faults(ggtt->vm.gt);
+ 
+       mutex_lock(&ggtt->vm.mutex);
+ 
+       /* First fill our portion of the GTT with scratch pages */
+       ggtt->vm.clear_range(&ggtt->vm, 0, ggtt->vm.total);
+ 
+       /* Skip rewriting PTE on VMA unbind. */
+       open = atomic_xchg(&ggtt->vm.open, 0);
+ 
+       /* clflush objects bound into the GGTT and rebind them. */
+       list_for_each_entry(vma, &ggtt->vm.bound_list, vm_link) {
+               struct drm_i915_gem_object *obj = vma->obj;
+ 
+               if (!i915_vma_is_bound(vma, I915_VMA_GLOBAL_BIND))
+                       continue;
+ 
+               clear_bit(I915_VMA_GLOBAL_BIND_BIT, __i915_vma_flags(vma));
+               WARN_ON(i915_vma_bind(vma,
+                                     obj ? obj->cache_level : 0,
+                                     PIN_GLOBAL, NULL));
+               if (obj) { /* only used during resume => exclusive access */
+                       flush |= fetch_and_zero(&obj->write_domain);
+                       obj->read_domains |= I915_GEM_DOMAIN_GTT;
+               }
+       }
+ 
+       atomic_set(&ggtt->vm.open, open);
+       ggtt->invalidate(ggtt);
+ 
+       mutex_unlock(&ggtt->vm.mutex);
+ 
+       if (flush)
+               wbinvd_on_all_cpus();
+ }
+ 
+ void i915_gem_restore_gtt_mappings(struct drm_i915_private *i915)
+ {
+       struct i915_ggtt *ggtt = &i915->ggtt;
+ 
+       ggtt_restore_mappings(ggtt);
+ 
+       if (INTEL_GEN(i915) >= 8)
+               setup_private_pat(ggtt->vm.gt->uncore);
+ }
+ 
+ static struct scatterlist *
+ rotate_pages(struct drm_i915_gem_object *obj, unsigned int offset,
+            unsigned int width, unsigned int height,
+            unsigned int stride,
+            struct sg_table *st, struct scatterlist *sg)
+ {
+       unsigned int column, row;
+       unsigned int src_idx;
+ 
+       for (column = 0; column < width; column++) {
+               src_idx = stride * (height - 1) + column + offset;
+               for (row = 0; row < height; row++) {
+                       st->nents++;
+                       /*
+                        * We don't need the pages, but need to initialize
+                        * the entries so the sg list can be happily traversed.
+                        * The only thing we need are DMA addresses.
+                        */
+                       sg_set_page(sg, NULL, I915_GTT_PAGE_SIZE, 0);
+                       sg_dma_address(sg) =
+                               i915_gem_object_get_dma_address(obj, src_idx);
+                       sg_dma_len(sg) = I915_GTT_PAGE_SIZE;
+                       sg = sg_next(sg);
+                       src_idx -= stride;
+               }
+       }
+ 
+       return sg;
+ }
+ 
+ static noinline struct sg_table *
+ intel_rotate_pages(struct intel_rotation_info *rot_info,
+                  struct drm_i915_gem_object *obj)
+ {
+       unsigned int size = intel_rotation_info_size(rot_info);
+       struct sg_table *st;
+       struct scatterlist *sg;
+       int ret = -ENOMEM;
+       int i;
+ 
+       /* Allocate target SG list. */
+       st = kmalloc(sizeof(*st), GFP_KERNEL);
+       if (!st)
+               goto err_st_alloc;
+ 
+       ret = sg_alloc_table(st, size, GFP_KERNEL);
+       if (ret)
+               goto err_sg_alloc;
+ 
+       st->nents = 0;
+       sg = st->sgl;
+ 
+       for (i = 0 ; i < ARRAY_SIZE(rot_info->plane); i++) {
+               sg = rotate_pages(obj, rot_info->plane[i].offset,
+                                 rot_info->plane[i].width, rot_info->plane[i].height,
+                                 rot_info->plane[i].stride, st, sg);
+       }
+ 
+       return st;
+ 
+ err_sg_alloc:
+       kfree(st);
+ err_st_alloc:
+ 
+       DRM_DEBUG_DRIVER("Failed to create rotated mapping for object size %zu! (%ux%u tiles, %u pages)\n",
+                        obj->base.size, rot_info->plane[0].width, rot_info->plane[0].height, size);
+ 
+       return ERR_PTR(ret);
+ }
+ 
+ static struct scatterlist *
+ remap_pages(struct drm_i915_gem_object *obj, unsigned int offset,
+           unsigned int width, unsigned int height,
+           unsigned int stride,
+           struct sg_table *st, struct scatterlist *sg)
+ {
+       unsigned int row;
+ 
+       for (row = 0; row < height; row++) {
+               unsigned int left = width * I915_GTT_PAGE_SIZE;
+ 
+               while (left) {
+                       dma_addr_t addr;
+                       unsigned int length;
+ 
+                       /*
+                        * We don't need the pages, but need to initialize
+                        * the entries so the sg list can be happily traversed.
+                        * The only thing we need are DMA addresses.
+                        */
+ 
+                       addr = i915_gem_object_get_dma_address_len(obj, offset, &length);
+ 
+                       length = min(left, length);
+ 
+                       st->nents++;
+ 
+                       sg_set_page(sg, NULL, length, 0);
+                       sg_dma_address(sg) = addr;
+                       sg_dma_len(sg) = length;
+                       sg = sg_next(sg);
+ 
+                       offset += length / I915_GTT_PAGE_SIZE;
+                       left -= length;
+               }
+ 
+               offset += stride - width;
+       }
+ 
+       return sg;
+ }
+ 
+ static noinline struct sg_table *
+ intel_remap_pages(struct intel_remapped_info *rem_info,
+                 struct drm_i915_gem_object *obj)
+ {
+       unsigned int size = intel_remapped_info_size(rem_info);
+       struct sg_table *st;
+       struct scatterlist *sg;
+       int ret = -ENOMEM;
+       int i;
+ 
+       /* Allocate target SG list. */
+       st = kmalloc(sizeof(*st), GFP_KERNEL);
+       if (!st)
+               goto err_st_alloc;
+ 
+       ret = sg_alloc_table(st, size, GFP_KERNEL);
+       if (ret)
+               goto err_sg_alloc;
+ 
+       st->nents = 0;
+       sg = st->sgl;
+ 
+       for (i = 0 ; i < ARRAY_SIZE(rem_info->plane); i++) {
+               sg = remap_pages(obj, rem_info->plane[i].offset,
+                                rem_info->plane[i].width, rem_info->plane[i].height,
+                                rem_info->plane[i].stride, st, sg);
+       }
+ 
+       i915_sg_trim(st);
+ 
+       return st;
+ 
+ err_sg_alloc:
+       kfree(st);
+ err_st_alloc:
+ 
+       DRM_DEBUG_DRIVER("Failed to create remapped mapping for object size %zu! (%ux%u tiles, %u pages)\n",
+                        obj->base.size, rem_info->plane[0].width, rem_info->plane[0].height, size);
+ 
+       return ERR_PTR(ret);
+ }
+ 
+ static noinline struct sg_table *
+ intel_partial_pages(const struct i915_ggtt_view *view,
+                   struct drm_i915_gem_object *obj)
+ {
+       struct sg_table *st;
+       struct scatterlist *sg, *iter;
+       unsigned int count = view->partial.size;
+       unsigned int offset;
+       int ret = -ENOMEM;
+ 
+       st = kmalloc(sizeof(*st), GFP_KERNEL);
+       if (!st)
+               goto err_st_alloc;
+ 
+       ret = sg_alloc_table(st, count, GFP_KERNEL);
+       if (ret)
+               goto err_sg_alloc;
+ 
+       iter = i915_gem_object_get_sg(obj, view->partial.offset, &offset);
+       GEM_BUG_ON(!iter);
+ 
+       sg = st->sgl;
+       st->nents = 0;
+       do {
+               unsigned int len;
+ 
+               len = min(iter->length - (offset << PAGE_SHIFT),
+                         count << PAGE_SHIFT);
+               sg_set_page(sg, NULL, len, 0);
+               sg_dma_address(sg) =
+                       sg_dma_address(iter) + (offset << PAGE_SHIFT);
+               sg_dma_len(sg) = len;
+ 
+               st->nents++;
+               count -= len >> PAGE_SHIFT;
+               if (count == 0) {
+                       sg_mark_end(sg);
+                       i915_sg_trim(st); /* Drop any unused tail entries. */
+ 
+                       return st;
+               }
+ 
+               sg = __sg_next(sg);
+               iter = __sg_next(iter);
+               offset = 0;
+       } while (1);
+ 
+ err_sg_alloc:
+       kfree(st);
+ err_st_alloc:
+       return ERR_PTR(ret);
+ }
+ 
+ static int
+ i915_get_ggtt_vma_pages(struct i915_vma *vma)
+ {
+       int ret;
+ 
+       /*
+        * The vma->pages are only valid within the lifespan of the borrowed
+        * obj->mm.pages. When the obj->mm.pages sg_table is regenerated, so
+        * must be the vma->pages. A simple rule is that vma->pages must only
+        * be accessed when the obj->mm.pages are pinned.
+        */
+       GEM_BUG_ON(!i915_gem_object_has_pinned_pages(vma->obj));
+ 
+       switch (vma->ggtt_view.type) {
+       default:
+               GEM_BUG_ON(vma->ggtt_view.type);
+               /* fall through */
+       case I915_GGTT_VIEW_NORMAL:
+               vma->pages = vma->obj->mm.pages;
+               return 0;
+ 
+       case I915_GGTT_VIEW_ROTATED:
+               vma->pages =
+                       intel_rotate_pages(&vma->ggtt_view.rotated, vma->obj);
+               break;
+ 
+       case I915_GGTT_VIEW_REMAPPED:
+               vma->pages =
+                       intel_remap_pages(&vma->ggtt_view.remapped, vma->obj);
+               break;
+ 
+       case I915_GGTT_VIEW_PARTIAL:
+               vma->pages = intel_partial_pages(&vma->ggtt_view, vma->obj);
+               break;
+       }
+ 
+       ret = 0;
+       if (IS_ERR(vma->pages)) {
+               ret = PTR_ERR(vma->pages);
+               vma->pages = NULL;
+               DRM_ERROR("Failed to get pages for VMA view type %u (%d)!\n",
+                         vma->ggtt_view.type, ret);
+       }
+       return ret;
+ }