diff mbox series

[1/1] drm/i915: Replace shmem memory region and object backend with TTM

Message ID 20220427113404.401741-2-adrian.larumbe@collabora.com (mailing list archive)
State New, archived
Headers show
Series Replace shmem memory region and object backend with TTM | expand

Commit Message

Adrián Larumbe April 27, 2022, 11:34 a.m. UTC
Remove shmem region and object backend code as they are now unnecessary.
In the case of objects placed in SMEM and backed by kernel shmem files, the
file pointer has to be retrieved from the ttm_tt structure, so change this
as well. This means accessing an shmem-backed BO's file pointer requires
getting its pages beforehand, unlike in the old shmem backend.

Expand TTM BO creation by handling devices with no LLC so that their
caching and coherency properties are set accordingly.

Signed-off-by: Adrian Larumbe <adrian.larumbe@collabora.com>
---
 drivers/gpu/drm/i915/gem/i915_gem_dmabuf.c   |  12 +-
 drivers/gpu/drm/i915/gem/i915_gem_mman.c     |  32 +-
 drivers/gpu/drm/i915/gem/i915_gem_object.h   |   2 +-
 drivers/gpu/drm/i915/gem/i915_gem_phys.c     |   5 +-
 drivers/gpu/drm/i915/gem/i915_gem_shmem.c    | 397 +------------------
 drivers/gpu/drm/i915/gem/i915_gem_ttm.c      | 212 +++++++++-
 drivers/gpu/drm/i915/gem/i915_gem_ttm.h      |   3 +
 drivers/gpu/drm/i915/gem/i915_gem_ttm_move.c |  11 +-
 drivers/gpu/drm/i915/gt/shmem_utils.c        |  64 ++-
 drivers/gpu/drm/i915/intel_memory_region.c   |   7 +-
 10 files changed, 333 insertions(+), 412 deletions(-)

Comments

Matthew Auld April 28, 2022, 6:04 p.m. UTC | #1
On Thu, 28 Apr 2022 at 09:39, Adrian Larumbe
<adrian.larumbe@collabora.com> wrote:
>
> Remove shmem region and object backend code as they are now unnecessary.
> In the case of objects placed in SMEM and backed by kernel shmem files, the
> file pointer has to be retrieved from the ttm_tt structure, so change this
> as well. This means accessing an shmem-backed BO's file pointer requires
> getting its pages beforehand, unlike in the old shmem backend.
>
> Expand TTM BO creation by handling devices with no LLC so that their
> caching and coherency properties are set accordingly.
>
> Signed-off-by: Adrian Larumbe <adrian.larumbe@collabora.com>
> ---
>  drivers/gpu/drm/i915/gem/i915_gem_dmabuf.c   |  12 +-
>  drivers/gpu/drm/i915/gem/i915_gem_mman.c     |  32 +-
>  drivers/gpu/drm/i915/gem/i915_gem_object.h   |   2 +-
>  drivers/gpu/drm/i915/gem/i915_gem_phys.c     |   5 +-
>  drivers/gpu/drm/i915/gem/i915_gem_shmem.c    | 397 +------------------
>  drivers/gpu/drm/i915/gem/i915_gem_ttm.c      | 212 +++++++++-
>  drivers/gpu/drm/i915/gem/i915_gem_ttm.h      |   3 +
>  drivers/gpu/drm/i915/gem/i915_gem_ttm_move.c |  11 +-
>  drivers/gpu/drm/i915/gt/shmem_utils.c        |  64 ++-
>  drivers/gpu/drm/i915/intel_memory_region.c   |   7 +-
>  10 files changed, 333 insertions(+), 412 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/gem/i915_gem_dmabuf.c b/drivers/gpu/drm/i915/gem/i915_gem_dmabuf.c
> index f5062d0c6333..de04ce4210b3 100644
> --- a/drivers/gpu/drm/i915/gem/i915_gem_dmabuf.c
> +++ b/drivers/gpu/drm/i915/gem/i915_gem_dmabuf.c
> @@ -12,6 +12,7 @@
>  #include <asm/smp.h>
>
>  #include "gem/i915_gem_dmabuf.h"
> +#include "gem/i915_gem_ttm.h"
>  #include "i915_drv.h"
>  #include "i915_gem_object.h"
>  #include "i915_scatterlist.h"
> @@ -94,22 +95,25 @@ static int i915_gem_dmabuf_mmap(struct dma_buf *dma_buf, struct vm_area_struct *
>  {
>         struct drm_i915_gem_object *obj = dma_buf_to_obj(dma_buf);
>         struct drm_i915_private *i915 = to_i915(obj->base.dev);
> +       struct file *filp = i915_gem_ttm_get_filep(obj);
>         int ret;
>
> +       GEM_BUG_ON(obj->base.import_attach != NULL);
> +
>         if (obj->base.size < vma->vm_end - vma->vm_start)
>                 return -EINVAL;
>
>         if (HAS_LMEM(i915))
>                 return drm_gem_prime_mmap(&obj->base, vma);
>
> -       if (!obj->base.filp)
> +       if (!filp)
>                 return -ENODEV;
>
> -       ret = call_mmap(obj->base.filp, vma);
> +       ret = call_mmap(filp, vma);
>         if (ret)
>                 return ret;
>
> -       vma_set_file(vma, obj->base.filp);
> +       vma_set_file(vma, filp);
>
>         return 0;
>  }
> @@ -224,6 +228,8 @@ struct dma_buf *i915_gem_prime_export(struct drm_gem_object *gem_obj, int flags)
>         exp_info.priv = gem_obj;
>         exp_info.resv = obj->base.resv;
>
> +       GEM_BUG_ON(obj->base.import_attach != NULL);
> +
>         if (obj->ops->dmabuf_export) {
>                 int ret = obj->ops->dmabuf_export(obj);
>                 if (ret)
> diff --git a/drivers/gpu/drm/i915/gem/i915_gem_mman.c b/drivers/gpu/drm/i915/gem/i915_gem_mman.c
> index 0c5c43852e24..d963cf35fdc9 100644
> --- a/drivers/gpu/drm/i915/gem/i915_gem_mman.c
> +++ b/drivers/gpu/drm/i915/gem/i915_gem_mman.c
> @@ -64,7 +64,9 @@ i915_gem_mmap_ioctl(struct drm_device *dev, void *data,
>         struct drm_i915_private *i915 = to_i915(dev);
>         struct drm_i915_gem_mmap *args = data;
>         struct drm_i915_gem_object *obj;
> +       struct file *filp;
>         unsigned long addr;
> +       int ret;
>
>         /*
>          * mmap ioctl is disallowed for all discrete platforms,
> @@ -83,12 +85,20 @@ i915_gem_mmap_ioctl(struct drm_device *dev, void *data,
>         if (!obj)
>                 return -ENOENT;
>
> -       /* prime objects have no backing filp to GEM mmap
> -        * pages from.
> -        */
> -       if (!obj->base.filp) {
> -               addr = -ENXIO;
> -               goto err;
> +       if (obj->base.import_attach)
> +               filp = obj->base.filp;
> +       else {
> +               ret = i915_gem_object_pin_pages_unlocked(obj);
> +               if (ret) {
> +                       addr = ret;
> +                       goto err_pin;
> +               }
> +
> +               filp = i915_gem_ttm_get_filep(obj);
> +               if (!filp) {
> +                       addr = -ENXIO;
> +                       goto err;
> +               }
>         }
>
>         if (range_overflows(args->offset, args->size, (u64)obj->base.size)) {
> @@ -96,7 +106,7 @@ i915_gem_mmap_ioctl(struct drm_device *dev, void *data,
>                 goto err;
>         }
>
> -       addr = vm_mmap(obj->base.filp, 0, args->size,
> +       addr = vm_mmap(filp, 0, args->size,
>                        PROT_READ | PROT_WRITE, MAP_SHARED,
>                        args->offset);
>         if (IS_ERR_VALUE(addr))
> @@ -111,7 +121,7 @@ i915_gem_mmap_ioctl(struct drm_device *dev, void *data,
>                         goto err;
>                 }
>                 vma = find_vma(mm, addr);
> -               if (vma && __vma_matches(vma, obj->base.filp, addr, args->size))
> +               if (vma && __vma_matches(vma, filp, addr, args->size))
>                         vma->vm_page_prot =
>                                 pgprot_writecombine(vm_get_page_prot(vma->vm_flags));
>                 else
> @@ -120,12 +130,18 @@ i915_gem_mmap_ioctl(struct drm_device *dev, void *data,
>                 if (IS_ERR_VALUE(addr))
>                         goto err;
>         }
> +       if (!obj->base.import_attach)
> +               i915_gem_object_unpin_pages(obj);
> +
>         i915_gem_object_put(obj);
>
>         args->addr_ptr = (u64)addr;
>         return 0;
>
>  err:
> +       if (!obj->base.import_attach)
> +               i915_gem_object_unpin_pages(obj);
> +err_pin:
>         i915_gem_object_put(obj);
>         return addr;
>  }
> diff --git a/drivers/gpu/drm/i915/gem/i915_gem_object.h b/drivers/gpu/drm/i915/gem/i915_gem_object.h
> index e11d82a9f7c3..a12f2733075a 100644
> --- a/drivers/gpu/drm/i915/gem/i915_gem_object.h
> +++ b/drivers/gpu/drm/i915/gem/i915_gem_object.h
> @@ -592,7 +592,7 @@ i915_gem_object_invalidate_frontbuffer(struct drm_i915_gem_object *obj,
>
>  int i915_gem_object_read_from_page(struct drm_i915_gem_object *obj, u64 offset, void *dst, int size);
>
> -bool i915_gem_object_is_shmem(const struct drm_i915_gem_object *obj);
> +bool i915_gem_object_is_shmem(struct drm_i915_gem_object *obj);
>
>  void __i915_gem_free_object_rcu(struct rcu_head *head);
>
> diff --git a/drivers/gpu/drm/i915/gem/i915_gem_phys.c b/drivers/gpu/drm/i915/gem/i915_gem_phys.c
> index 0d0e46dae559..af3c1c43000c 100644
> --- a/drivers/gpu/drm/i915/gem/i915_gem_phys.c
> +++ b/drivers/gpu/drm/i915/gem/i915_gem_phys.c
> @@ -11,6 +11,7 @@
>  #include <drm/drm_cache.h>
>
>  #include "gt/intel_gt.h"
> +#include "gem/i915_gem_ttm.h"
>  #include "i915_drv.h"
>  #include "i915_gem_object.h"
>  #include "i915_gem_region.h"
> @@ -19,7 +20,7 @@
>
>  static int i915_gem_object_get_pages_phys(struct drm_i915_gem_object *obj)
>  {
> -       struct address_space *mapping = obj->base.filp->f_mapping;
> +       struct address_space *mapping = i915_gem_ttm_get_filep(obj)->f_mapping;
>         struct drm_i915_private *i915 = to_i915(obj->base.dev);
>         struct scatterlist *sg;
>         struct sg_table *st;
> @@ -28,6 +29,8 @@ static int i915_gem_object_get_pages_phys(struct drm_i915_gem_object *obj)
>         void *dst;
>         int i;
>
> +       GEM_BUG_ON(obj->base.import_attach != NULL);
> +
>         if (GEM_WARN_ON(i915_gem_object_needs_bit17_swizzle(obj)))
>                 return -EINVAL;
>
> diff --git a/drivers/gpu/drm/i915/gem/i915_gem_shmem.c b/drivers/gpu/drm/i915/gem/i915_gem_shmem.c
> index c2a3e388fcb4..343eb5897a36 100644
> --- a/drivers/gpu/drm/i915/gem/i915_gem_shmem.c
> +++ b/drivers/gpu/drm/i915/gem/i915_gem_shmem.c
> @@ -11,12 +11,14 @@
>  #include <drm/drm_cache.h>
>
>  #include "gem/i915_gem_region.h"
> +#include "gem/i915_gem_ttm.h"
>  #include "i915_drv.h"
>  #include "i915_gem_object.h"
>  #include "i915_gem_tiling.h"
>  #include "i915_gemfs.h"
>  #include "i915_scatterlist.h"
>  #include "i915_trace.h"
> +#include "i915_gem_clflush.h"
>
>  /*
>   * Move pages to appropriate lru and release the pagevec, decrementing the
> @@ -188,105 +190,6 @@ int shmem_sg_alloc_table(struct drm_i915_private *i915, struct sg_table *st,
>         return ret;
>  }
>
> -static int shmem_get_pages(struct drm_i915_gem_object *obj)
> -{
> -       struct drm_i915_private *i915 = to_i915(obj->base.dev);
> -       struct intel_memory_region *mem = obj->mm.region;
> -       struct address_space *mapping = obj->base.filp->f_mapping;
> -       const unsigned long page_count = obj->base.size / PAGE_SIZE;
> -       unsigned int max_segment = i915_sg_segment_size();
> -       struct sg_table *st;
> -       struct sgt_iter sgt_iter;
> -       struct page *page;
> -       int ret;
> -
> -       /*
> -        * Assert that the object is not currently in any GPU domain. As it
> -        * wasn't in the GTT, there shouldn't be any way it could have been in
> -        * a GPU cache
> -        */
> -       GEM_BUG_ON(obj->read_domains & I915_GEM_GPU_DOMAINS);
> -       GEM_BUG_ON(obj->write_domain & I915_GEM_GPU_DOMAINS);
> -
> -rebuild_st:
> -       st = kmalloc(sizeof(*st), GFP_KERNEL);
> -       if (!st)
> -               return -ENOMEM;
> -
> -       ret = shmem_sg_alloc_table(i915, st, obj->base.size, mem, mapping,
> -                                  max_segment);
> -       if (ret)
> -               goto err_st;
> -
> -       ret = i915_gem_gtt_prepare_pages(obj, st);
> -       if (ret) {
> -               /*
> -                * DMA remapping failed? One possible cause is that
> -                * it could not reserve enough large entries, asking
> -                * for PAGE_SIZE chunks instead may be helpful.
> -                */
> -               if (max_segment > PAGE_SIZE) {
> -                       for_each_sgt_page(page, sgt_iter, st)
> -                               put_page(page);
> -                       sg_free_table(st);
> -                       kfree(st);
> -
> -                       max_segment = PAGE_SIZE;
> -                       goto rebuild_st;
> -               } else {
> -                       dev_warn(i915->drm.dev,
> -                                "Failed to DMA remap %lu pages\n",
> -                                page_count);
> -                       goto err_pages;
> -               }
> -       }
> -
> -       if (i915_gem_object_needs_bit17_swizzle(obj))
> -               i915_gem_object_do_bit_17_swizzle(obj, st);
> -
> -       if (i915_gem_object_can_bypass_llc(obj))
> -               obj->cache_dirty = true;
> -
> -       __i915_gem_object_set_pages(obj, st, i915_sg_dma_sizes(st->sgl));
> -
> -       return 0;
> -
> -err_pages:
> -       shmem_sg_free_table(st, mapping, false, false);
> -       /*
> -        * shmemfs first checks if there is enough memory to allocate the page
> -        * and reports ENOSPC should there be insufficient, along with the usual
> -        * ENOMEM for a genuine allocation failure.
> -        *
> -        * We use ENOSPC in our driver to mean that we have run out of aperture
> -        * space and so want to translate the error from shmemfs back to our
> -        * usual understanding of ENOMEM.
> -        */
> -err_st:
> -       if (ret == -ENOSPC)
> -               ret = -ENOMEM;
> -
> -       kfree(st);
> -
> -       return ret;
> -}
> -
> -static int
> -shmem_truncate(struct drm_i915_gem_object *obj)
> -{
> -       /*
> -        * Our goal here is to return as much of the memory as
> -        * is possible back to the system as we are called from OOM.
> -        * To do this we must instruct the shmfs to drop all of its
> -        * backing pages, *now*.
> -        */
> -       shmem_truncate_range(file_inode(obj->base.filp), 0, (loff_t)-1);
> -       obj->mm.madv = __I915_MADV_PURGED;
> -       obj->mm.pages = ERR_PTR(-EFAULT);
> -
> -       return 0;
> -}
> -
>  void __shmem_writeback(size_t size, struct address_space *mapping)
>  {
>         struct writeback_control wbc = {
> @@ -329,27 +232,6 @@ void __shmem_writeback(size_t size, struct address_space *mapping)
>         }
>  }
>
> -static void
> -shmem_writeback(struct drm_i915_gem_object *obj)
> -{
> -       __shmem_writeback(obj->base.size, obj->base.filp->f_mapping);
> -}
> -
> -static int shmem_shrink(struct drm_i915_gem_object *obj, unsigned int flags)
> -{
> -       switch (obj->mm.madv) {
> -       case I915_MADV_DONTNEED:
> -               return i915_gem_object_truncate(obj);
> -       case __I915_MADV_PURGED:
> -               return 0;
> -       }
> -
> -       if (flags & I915_GEM_OBJECT_SHRINK_WRITEBACK)
> -               shmem_writeback(obj);
> -
> -       return 0;
> -}
> -
>  void
>  __i915_gem_object_release_shmem(struct drm_i915_gem_object *obj,
>                                 struct sg_table *pages,
> @@ -395,220 +277,6 @@ void i915_gem_object_put_pages_shmem(struct drm_i915_gem_object *obj, struct sg_
>         obj->mm.dirty = false;
>  }
>
> -static void
> -shmem_put_pages(struct drm_i915_gem_object *obj, struct sg_table *pages)
> -{
> -       if (likely(i915_gem_object_has_struct_page(obj)))
> -               i915_gem_object_put_pages_shmem(obj, pages);
> -       else
> -               i915_gem_object_put_pages_phys(obj, pages);
> -}
> -
> -static int
> -shmem_pwrite(struct drm_i915_gem_object *obj,
> -            const struct drm_i915_gem_pwrite *arg)
> -{
> -       struct address_space *mapping = obj->base.filp->f_mapping;
> -       char __user *user_data = u64_to_user_ptr(arg->data_ptr);
> -       u64 remain, offset;
> -       unsigned int pg;
> -
> -       /* Caller already validated user args */
> -       GEM_BUG_ON(!access_ok(user_data, arg->size));
> -
> -       if (!i915_gem_object_has_struct_page(obj))
> -               return i915_gem_object_pwrite_phys(obj, arg);
> -
> -       /*
> -        * Before we instantiate/pin the backing store for our use, we
> -        * can prepopulate the shmemfs filp efficiently using a write into
> -        * the pagecache. We avoid the penalty of instantiating all the
> -        * pages, important if the user is just writing to a few and never
> -        * uses the object on the GPU, and using a direct write into shmemfs
> -        * allows it to avoid the cost of retrieving a page (either swapin
> -        * or clearing-before-use) before it is overwritten.
> -        */
> -       if (i915_gem_object_has_pages(obj))
> -               return -ENODEV;
> -
> -       if (obj->mm.madv != I915_MADV_WILLNEED)
> -               return -EFAULT;
> -
> -       /*
> -        * Before the pages are instantiated the object is treated as being
> -        * in the CPU domain. The pages will be clflushed as required before
> -        * use, and we can freely write into the pages directly. If userspace
> -        * races pwrite with any other operation; corruption will ensue -
> -        * that is userspace's prerogative!
> -        */
> -
> -       remain = arg->size;
> -       offset = arg->offset;
> -       pg = offset_in_page(offset);
> -
> -       do {
> -               unsigned int len, unwritten;
> -               struct page *page;
> -               void *data, *vaddr;
> -               int err;
> -               char c;
> -
> -               len = PAGE_SIZE - pg;
> -               if (len > remain)
> -                       len = remain;
> -
> -               /* Prefault the user page to reduce potential recursion */
> -               err = __get_user(c, user_data);
> -               if (err)
> -                       return err;
> -
> -               err = __get_user(c, user_data + len - 1);
> -               if (err)
> -                       return err;
> -
> -               err = pagecache_write_begin(obj->base.filp, mapping,
> -                                           offset, len, 0,
> -                                           &page, &data);
> -               if (err < 0)
> -                       return err;
> -
> -               vaddr = kmap_atomic(page);
> -               unwritten = __copy_from_user_inatomic(vaddr + pg,
> -                                                     user_data,
> -                                                     len);
> -               kunmap_atomic(vaddr);
> -
> -               err = pagecache_write_end(obj->base.filp, mapping,
> -                                         offset, len, len - unwritten,
> -                                         page, data);
> -               if (err < 0)
> -                       return err;
> -
> -               /* We don't handle -EFAULT, leave it to the caller to check */
> -               if (unwritten)
> -                       return -ENODEV;
> -
> -               remain -= len;
> -               user_data += len;
> -               offset += len;
> -               pg = 0;
> -       } while (remain);
> -
> -       return 0;
> -}
> -
> -static int
> -shmem_pread(struct drm_i915_gem_object *obj,
> -           const struct drm_i915_gem_pread *arg)
> -{
> -       if (!i915_gem_object_has_struct_page(obj))
> -               return i915_gem_object_pread_phys(obj, arg);
> -
> -       return -ENODEV;
> -}
> -
> -static void shmem_release(struct drm_i915_gem_object *obj)
> -{
> -       if (i915_gem_object_has_struct_page(obj))
> -               i915_gem_object_release_memory_region(obj);
> -
> -       fput(obj->base.filp);
> -}
> -
> -const struct drm_i915_gem_object_ops i915_gem_shmem_ops = {
> -       .name = "i915_gem_object_shmem",
> -       .flags = I915_GEM_OBJECT_IS_SHRINKABLE,
> -
> -       .get_pages = shmem_get_pages,
> -       .put_pages = shmem_put_pages,
> -       .truncate = shmem_truncate,
> -       .shrink = shmem_shrink,
> -
> -       .pwrite = shmem_pwrite,
> -       .pread = shmem_pread,
> -
> -       .release = shmem_release,
> -};
> -
> -static int __create_shmem(struct drm_i915_private *i915,
> -                         struct drm_gem_object *obj,
> -                         resource_size_t size)
> -{
> -       unsigned long flags = VM_NORESERVE;
> -       struct file *filp;
> -
> -       drm_gem_private_object_init(&i915->drm, obj, size);
> -
> -       if (i915->mm.gemfs)
> -               filp = shmem_file_setup_with_mnt(i915->mm.gemfs, "i915", size,
> -                                                flags);
> -       else
> -               filp = shmem_file_setup("i915", size, flags);
> -       if (IS_ERR(filp))
> -               return PTR_ERR(filp);
> -
> -       obj->filp = filp;
> -       return 0;
> -}
> -
> -static int shmem_object_init(struct intel_memory_region *mem,
> -                            struct drm_i915_gem_object *obj,
> -                            resource_size_t offset,
> -                            resource_size_t size,
> -                            resource_size_t page_size,
> -                            unsigned int flags)
> -{
> -       static struct lock_class_key lock_class;
> -       struct drm_i915_private *i915 = mem->i915;
> -       struct address_space *mapping;
> -       unsigned int cache_level;
> -       gfp_t mask;
> -       int ret;
> -
> -       ret = __create_shmem(i915, &obj->base, size);
> -       if (ret)
> -               return ret;
> -
> -       mask = GFP_HIGHUSER | __GFP_RECLAIMABLE;
> -       if (IS_I965GM(i915) || IS_I965G(i915)) {
> -               /* 965gm cannot relocate objects above 4GiB. */
> -               mask &= ~__GFP_HIGHMEM;
> -               mask |= __GFP_DMA32;
> -       }
> -
> -       mapping = obj->base.filp->f_mapping;
> -       mapping_set_gfp_mask(mapping, mask);
> -       GEM_BUG_ON(!(mapping_gfp_mask(mapping) & __GFP_RECLAIM));
> -
> -       i915_gem_object_init(obj, &i915_gem_shmem_ops, &lock_class, 0);
> -       obj->mem_flags |= I915_BO_FLAG_STRUCT_PAGE;
> -       obj->write_domain = I915_GEM_DOMAIN_CPU;
> -       obj->read_domains = I915_GEM_DOMAIN_CPU;
> -
> -       if (HAS_LLC(i915))
> -               /* On some devices, we can have the GPU use the LLC (the CPU
> -                * cache) for about a 10% performance improvement
> -                * compared to uncached.  Graphics requests other than
> -                * display scanout are coherent with the CPU in
> -                * accessing this cache.  This means in this mode we
> -                * don't need to clflush on the CPU side, and on the
> -                * GPU side we only need to flush internal caches to
> -                * get data visible to the CPU.
> -                *
> -                * However, we maintain the display planes as UC, and so
> -                * need to rebind when first used as such.
> -                */
> -               cache_level = I915_CACHE_LLC;
> -       else
> -               cache_level = I915_CACHE_NONE;
> -
> -       i915_gem_object_set_cache_coherency(obj, cache_level);
> -
> -       i915_gem_object_init_memory_region(obj, mem);
> -
> -       return 0;
> -}
> -
>  struct drm_i915_gem_object *
>  i915_gem_object_create_shmem(struct drm_i915_private *i915,
>                              resource_size_t size)
> @@ -634,7 +302,19 @@ i915_gem_object_create_shmem_from_data(struct drm_i915_private *dev_priv,
>
>         GEM_BUG_ON(obj->write_domain != I915_GEM_DOMAIN_CPU);
>
> -       file = obj->base.filp;
> +       /*
> +        *  When using TTM as the main GEM backend, we need to pin the pages
> +        *  after creating the object to access the file pointer
> +        */
> +       err = i915_gem_object_pin_pages_unlocked(obj);
> +       if (err) {
> +               drm_dbg(&dev_priv->drm, "%s pin-pages err=%d\n", __func__, err);
> +               goto fail_pin;
> +       }
> +
> +       file = i915_gem_ttm_get_filep(obj);
> +       GEM_WARN_ON(file == NULL);
> +
>         offset = 0;
>         do {
>                 unsigned int len = min_t(typeof(size), size, PAGE_SIZE);
> @@ -662,51 +342,14 @@ i915_gem_object_create_shmem_from_data(struct drm_i915_private *dev_priv,
>                 offset += len;
>         } while (size);
>
> +       i915_gem_clflush_object(obj, I915_CLFLUSH_SYNC);
> +       i915_gem_object_unpin_pages(obj);
> +
>         return obj;
>
>  fail:
> +       i915_gem_object_unpin_pages(obj);
> +fail_pin:
>         i915_gem_object_put(obj);
>         return ERR_PTR(err);
>  }
> -
> -static int init_shmem(struct intel_memory_region *mem)
> -{
> -       int err;
> -
> -       err = i915_gemfs_init(mem->i915);
> -       if (err) {
> -               DRM_NOTE("Unable to create a private tmpfs mount, hugepage support will be disabled(%d).\n",
> -                        err);
> -       }
> -
> -       intel_memory_region_set_name(mem, "system");
> -
> -       return 0; /* Don't error, we can simply fallback to the kernel mnt */
> -}
> -
> -static int release_shmem(struct intel_memory_region *mem)
> -{
> -       i915_gemfs_fini(mem->i915);
> -       return 0;
> -}
> -
> -static const struct intel_memory_region_ops shmem_region_ops = {
> -       .init = init_shmem,
> -       .release = release_shmem,
> -       .init_object = shmem_object_init,
> -};
> -
> -struct intel_memory_region *i915_gem_shmem_setup(struct drm_i915_private *i915,
> -                                                u16 type, u16 instance)
> -{
> -       return intel_memory_region_create(i915, 0,
> -                                         totalram_pages() << PAGE_SHIFT,
> -                                         PAGE_SIZE, 0, 0,
> -                                         type, instance,
> -                                         &shmem_region_ops);
> -}
> -
> -bool i915_gem_object_is_shmem(const struct drm_i915_gem_object *obj)
> -{
> -       return obj->ops == &i915_gem_shmem_ops;
> -}
> diff --git a/drivers/gpu/drm/i915/gem/i915_gem_ttm.c b/drivers/gpu/drm/i915/gem/i915_gem_ttm.c
> index 4c25d9b2f138..e4f3a467abd8 100644
> --- a/drivers/gpu/drm/i915/gem/i915_gem_ttm.c
> +++ b/drivers/gpu/drm/i915/gem/i915_gem_ttm.c
> @@ -21,6 +21,7 @@
>  #include "gem/i915_gem_ttm_move.h"
>  #include "gem/i915_gem_ttm_pm.h"
>  #include "gt/intel_gpu_commands.h"
> +#include "gem/i915_gem_tiling.h"
>
>  #define I915_TTM_PRIO_PURGE     0
>  #define I915_TTM_PRIO_NO_PAGES  1
> @@ -37,6 +38,7 @@
>   * @ttm: The base TTM page vector.
>   * @dev: The struct device used for dma mapping and unmapping.
>   * @cached_rsgt: The cached scatter-gather table.
> + * @bo: TTM buffer object this ttm_tt structure is bound to.
>   * @is_shmem: Set if using shmem.
>   * @filp: The shmem file, if using shmem backend.
>   *
> @@ -50,6 +52,7 @@ struct i915_ttm_tt {
>         struct ttm_tt ttm;
>         struct device *dev;
>         struct i915_refct_sgt cached_rsgt;
> +       struct ttm_buffer_object *bo;
>
>         bool is_shmem;
>         struct file *filp;
> @@ -113,6 +116,10 @@ static int i915_ttm_err_to_gem(int err)
>  static enum ttm_caching
>  i915_ttm_select_tt_caching(const struct drm_i915_gem_object *obj)
>  {
> +       struct drm_i915_private *i915 = to_i915(obj->base.dev);
> +
> +       if (GRAPHICS_VER(i915) <= 5)
> +               return ttm_uncached;
>         /*
>          * Objects only allowed in system get cached cpu-mappings, or when
>          * evicting lmem-only buffers to system for swapping. Other objects get
> @@ -207,6 +214,11 @@ static int i915_ttm_tt_shmem_populate(struct ttm_device *bdev,
>                         return PTR_ERR(filp);
>
>                 mask = GFP_HIGHUSER | __GFP_RECLAIMABLE;
> +               if (IS_I965GM(i915) || IS_I965G(i915)) {
> +                       /* 965gm cannot relocate objects above 4GiB. */
> +                       mask &= ~__GFP_HIGHMEM;
> +                       mask |= __GFP_DMA32;
> +               }
>
>                 mapping = filp->f_mapping;
>                 mapping_set_gfp_mask(mapping, mask);
> @@ -304,12 +316,14 @@ static struct ttm_tt *i915_ttm_tt_create(struct ttm_buffer_object *bo,
>         if (!i915_tt)
>                 return NULL;
>
> +       i915_tt->bo = bo;
> +
>         if (obj->flags & I915_BO_ALLOC_CPU_CLEAR &&
>             man->use_tt)
>                 page_flags |= TTM_TT_FLAG_ZERO_ALLOC;
>
>         caching = i915_ttm_select_tt_caching(obj);
> -       if (i915_gem_object_is_shrinkable(obj) && caching == ttm_cached) {
> +       if (i915_gem_object_is_shrinkable(obj) && (caching != ttm_write_combined)) {
>                 page_flags |= TTM_TT_FLAG_EXTERNAL |
>                               TTM_TT_FLAG_EXTERNAL_MAPPABLE;
>                 i915_tt->is_shmem = true;
> @@ -352,11 +366,19 @@ static void i915_ttm_tt_unpopulate(struct ttm_device *bdev, struct ttm_tt *ttm)
>  {
>         struct i915_ttm_tt *i915_tt = container_of(ttm, typeof(*i915_tt), ttm);
>         struct sg_table *st = &i915_tt->cached_rsgt.table;
> +       struct ttm_buffer_object *bo = i915_tt->bo;
> +       struct drm_i915_gem_object *obj = i915_ttm_to_gem(bo);
> +
> +       if (i915_tt->is_shmem)
> +               __i915_gem_object_release_shmem(obj, st, true);
>
>         if (st->sgl)
>                 dma_unmap_sgtable(i915_tt->dev, st, DMA_BIDIRECTIONAL, 0);
>
>         if (i915_tt->is_shmem) {
> +               if (i915_gem_object_needs_bit17_swizzle(obj))
> +                       i915_gem_object_save_bit_17_swizzle(obj, st);
> +
>                 i915_ttm_tt_shmem_unpopulate(ttm);
>         } else {
>                 sg_free_table(st);
> @@ -798,6 +820,12 @@ static int __i915_ttm_get_pages(struct drm_i915_gem_object *obj,
>                 obj->mm.rsgt = rsgt;
>                 __i915_gem_object_set_pages(obj, &rsgt->table,
>                                             i915_sg_dma_sizes(rsgt->table.sgl));
> +
> +               if (i915_gem_object_needs_bit17_swizzle(obj))
> +                       i915_gem_object_save_bit_17_swizzle(obj, &rsgt->table);
> +
> +               if (i915_gem_object_can_bypass_llc(obj))
> +                       obj->cache_dirty = true;

This needs to happen before the set_pages(), otherwise we are skipping
the flush-on-acquire.

>         }
>
>         GEM_BUG_ON(bo->ttm && ((obj->base.size >> PAGE_SHIFT) < bo->ttm->num_pages));
> @@ -979,6 +1007,119 @@ void i915_ttm_adjust_lru(struct drm_i915_gem_object *obj)
>         spin_unlock(&bo->bdev->lru_lock);
>  }
>
> +static int
> +i915_ttm_pwrite(struct drm_i915_gem_object *obj,
> +               const struct drm_i915_gem_pwrite *arg)
> +{
> +       struct drm_i915_private *i915 = to_i915(obj->base.dev);
> +       char __user *user_data = u64_to_user_ptr(arg->data_ptr);
> +       struct address_space *mapping;
> +       u64 remain, offset;
> +       struct file *filp;
> +       unsigned int pg;
> +       int err;
> +
> +       /* Caller already validated user args */
> +       GEM_BUG_ON(!access_ok(user_data, arg->size));
> +
> +       if (!i915_gem_object_has_struct_page(obj))
> +               return i915_gem_object_pwrite_phys(obj, arg);
> +
> +       /*
> +        * We need to pin the pages in order to have access to the filp
> +        * given by shmem, quite unlike in the legacy GEM shmem backend
> +        * where it would be available upon object creation
> +        */
> +       err = i915_gem_object_pin_pages_unlocked(obj);
> +       if (err) {
> +               drm_dbg(&i915->drm, "%s pin-pages err=%d\n", __func__, err);
> +               return err;
> +       }
> +
> +       filp = i915_gem_ttm_get_filep(obj);
> +       if (!filp) {
> +               err = -ENXIO;
> +               goto error;
> +       }
> +
> +       mapping = filp->f_mapping;
> +
> +       if (obj->mm.madv != I915_MADV_WILLNEED) {
> +               err = -EFAULT;
> +               goto error;
> +       }
> +
> +       /*
> +        * Before the pages are instantiated the object is treated as being
> +        * in the CPU domain. The pages will be clflushed as required before
> +        * use, and we can freely write into the pages directly. If userspace
> +        * races pwrite with any other operation; corruption will ensue -
> +        * that is userspace's prerogative!
> +        */
> +
> +       remain = arg->size;
> +       offset = arg->offset;
> +       pg = offset_in_page(offset);
> +
> +       do {
> +               unsigned int len, unwritten;
> +               struct page *page;
> +               void *data, *vaddr;
> +               int err;
> +               char c;
> +
> +               len = PAGE_SIZE - pg;
> +               if (len > remain)
> +                       len = remain;
> +
> +               /* Prefault the user page to reduce potential recursion */
> +               err = __get_user(c, user_data);
> +               if (err)
> +                       goto error;
> +
> +               err = __get_user(c, user_data + len - 1);
> +               if (err)
> +                       goto error;
> +
> +               err = pagecache_write_begin(obj->base.filp, mapping,
> +                                           offset, len, 0,
> +                                           &page, &data);
> +               if (err < 0)
> +                       goto error;
> +
> +               vaddr = kmap_atomic(page);
> +               unwritten = __copy_from_user_inatomic(vaddr + pg,
> +                                                     user_data,
> +                                                     len);
> +               kunmap_atomic(vaddr);
> +
> +               err = pagecache_write_end(obj->base.filp, mapping,
> +                                         offset, len, len - unwritten,
> +                                         page, data);
> +               if (err < 0)
> +                       goto error;
> +
> +               /* We don't handle -EFAULT, leave it to the caller to check */
> +               if (unwritten) {
> +                       err = -ENODEV;
> +                       goto error;
> +               }
> +
> +               remain -= len;
> +               user_data += len;
> +               offset += len;
> +               pg = 0;
> +       } while (remain);
> +
> +       i915_gem_object_unpin_pages(obj);
> +
> +       return 0;
> +
> +error:
> +       i915_gem_object_unpin_pages(obj);
> +       return err;
> +}
> +
>  /*
>   * TTM-backed gem object destruction requires some clarification.
>   * Basically we have two possibilities here. We can either rely on the
> @@ -1120,7 +1261,7 @@ static void i915_ttm_unmap_virtual(struct drm_i915_gem_object *obj)
>         ttm_bo_unmap_virtual(i915_gem_to_ttm(obj));
>  }
>
> -static const struct drm_i915_gem_object_ops i915_gem_ttm_obj_ops = {
> +static const struct drm_i915_gem_object_ops i915_gem_ttm_discrete_ops = {
>         .name = "i915_gem_object_ttm",
>         .flags = I915_GEM_OBJECT_IS_SHRINKABLE |
>                  I915_GEM_OBJECT_SELF_MANAGED_SHRINK_LIST,
> @@ -1139,6 +1280,22 @@ static const struct drm_i915_gem_object_ops i915_gem_ttm_obj_ops = {
>         .mmap_ops = &vm_ops_ttm,
>  };
>
> +static const struct drm_i915_gem_object_ops i915_gem_ttm_obj_integrated_ops = {
> +       .name = "i915_gem_object_ttm",
> +       .flags = I915_GEM_OBJECT_IS_SHRINKABLE |
> +                I915_GEM_OBJECT_SELF_MANAGED_SHRINK_LIST,
> +
> +       .get_pages = i915_ttm_get_pages,
> +       .put_pages = i915_ttm_put_pages,
> +       .truncate = i915_ttm_truncate,
> +       .shrink = i915_ttm_shrink,
> +
> +       .pwrite = i915_ttm_pwrite,
> +
> +       .adjust_lru = i915_ttm_adjust_lru,
> +       .delayed_free = i915_ttm_delayed_free,
> +};
> +
>  void i915_ttm_bo_destroy(struct ttm_buffer_object *bo)
>  {
>         struct drm_i915_gem_object *obj = i915_ttm_to_gem(bo);
> @@ -1196,7 +1353,12 @@ int __i915_gem_ttm_object_init(struct intel_memory_region *mem,
>         int ret;
>
>         drm_gem_private_object_init(&i915->drm, &obj->base, size);
> -       i915_gem_object_init(obj, &i915_gem_ttm_obj_ops, &lock_class, flags);
> +
> +       if (IS_DGFX(i915))
> +               i915_gem_object_init(obj, &i915_gem_ttm_discrete_ops, &lock_class, flags);
> +       else
> +               i915_gem_object_init(obj, &i915_gem_ttm_obj_integrated_ops, &lock_class,
> +                                    flags);
>
>         obj->bo_offset = offset;
>
> @@ -1206,8 +1368,8 @@ int __i915_gem_ttm_object_init(struct intel_memory_region *mem,
>
>         INIT_RADIX_TREE(&obj->ttm.get_io_page.radix, GFP_KERNEL | __GFP_NOWARN);
>         mutex_init(&obj->ttm.get_io_page.lock);
> -       bo_type = (obj->flags & I915_BO_ALLOC_USER) ? ttm_bo_type_device :
> -               ttm_bo_type_kernel;
> +       bo_type = (obj->ops->mmap_offset && (obj->flags & I915_BO_ALLOC_USER)) ?
> +               ttm_bo_type_device : ttm_bo_type_kernel;
>
>         obj->base.vma_node.driver_private = i915_gem_to_ttm(obj);
>
> @@ -1251,6 +1413,27 @@ static const struct intel_memory_region_ops ttm_system_region_ops = {
>         .release = intel_region_ttm_fini,
>  };
>
> +/**
> + * Return: filp.
> + */
> +struct file *
> +i915_gem_ttm_get_filep(struct drm_i915_gem_object *obj)
> +{
> +       struct drm_device *dev = obj->base.dev;
> +       struct ttm_buffer_object *bo;
> +       struct i915_ttm_tt *i915_tt;
> +
> +       bo = i915_gem_to_ttm(obj);
> +       if (!bo->ttm) {
> +               drm_dbg(dev, "ttm has not been allocated for bo\n");
> +               return NULL;
> +       }
> +
> +       i915_tt = container_of(bo->ttm, typeof(*i915_tt), ttm);
> +
> +       return i915_tt->filp;
> +}
> +
>  struct intel_memory_region *
>  i915_gem_ttm_system_setup(struct drm_i915_private *i915,
>                           u16 type, u16 instance)
> @@ -1268,3 +1451,22 @@ i915_gem_ttm_system_setup(struct drm_i915_private *i915,
>         intel_memory_region_set_name(mr, "system-ttm");
>         return mr;
>  }
> +
> +bool i915_gem_object_is_shmem(struct drm_i915_gem_object *obj)
> +{
> +       struct intel_memory_region *mr = READ_ONCE(obj->mm.region);
> +
> +#ifdef CONFIG_LOCKDEP
> +       if (i915_gem_object_migratable(obj) &&
> +           i915_gem_object_evictable(obj))
> +               assert_object_held(obj);
> +#endif
> +
> +       /* Review list of placements to make sure object isn't migratable */
> +       if (i915_gem_object_placement_possible(obj, INTEL_MEMORY_LOCAL))
> +               return false;
> +
> +       return mr && (mr->type == INTEL_MEMORY_SYSTEM &&
> +                     (obj->ops == &i915_gem_ttm_obj_integrated_ops ||
> +                      obj->ops == &i915_gem_ttm_discrete_ops));
> +}
> diff --git a/drivers/gpu/drm/i915/gem/i915_gem_ttm.h b/drivers/gpu/drm/i915/gem/i915_gem_ttm.h
> index 73e371aa3850..f00f18db5a8b 100644
> --- a/drivers/gpu/drm/i915/gem/i915_gem_ttm.h
> +++ b/drivers/gpu/drm/i915/gem/i915_gem_ttm.h
> @@ -92,4 +92,7 @@ static inline bool i915_ttm_cpu_maps_iomem(struct ttm_resource *mem)
>         /* Once / if we support GGTT, this is also false for cached ttm_tts */
>         return mem->mem_type != I915_PL_SYSTEM;
>  }
> +
> +struct file *i915_gem_ttm_get_filep(struct drm_i915_gem_object *obj);
> +
>  #endif
> diff --git a/drivers/gpu/drm/i915/gem/i915_gem_ttm_move.c b/drivers/gpu/drm/i915/gem/i915_gem_ttm_move.c
> index a10716f4e717..c588e31aa479 100644
> --- a/drivers/gpu/drm/i915/gem/i915_gem_ttm_move.c
> +++ b/drivers/gpu/drm/i915/gem/i915_gem_ttm_move.c
> @@ -46,6 +46,10 @@ static enum i915_cache_level
>  i915_ttm_cache_level(struct drm_i915_private *i915, struct ttm_resource *res,
>                      struct ttm_tt *ttm)
>  {
> +
> +       if (GRAPHICS_VER(i915) <= 5)
> +               return I915_CACHE_NONE;

IIUC we are no longer using CACHE_NONE by default on snooping
platforms gen > 5? That's a pretty big change, AFAIK there are power
and perf considerations when enabling CACHE_LLC/L3 on snooping
platforms, which is why it was disabled by default.

We also need to be careful to ensure we always set cache_dirty = true,
before first populating the pages on all HAS_SNOOP()
platforms(ignoring discrete) to ensure we always do the
flush-on-acquire. The CACHE_NONE thing was basically ensuring that
previously.

Can we keep the previous default behaviour with using CACHE_NONE on
all platforms that don't have HAS_LLC(), where it is not also
discrete?

We also need to ensure we never trample the cache_level etc for the
object after creation, since userspace(and some in-kernel users) needs
to be to able control it.

> +
>         return ((HAS_LLC(i915) || HAS_SNOOP(i915)) &&
>                 !i915_ttm_gtt_binds_lmem(res) &&
>                 ttm->caching == ttm_cached) ? I915_CACHE_LLC :
> @@ -77,7 +81,12 @@ void i915_ttm_adjust_domains_after_move(struct drm_i915_gem_object *obj)
>  {
>         struct ttm_buffer_object *bo = i915_gem_to_ttm(obj);
>
> -       if (i915_ttm_cpu_maps_iomem(bo->resource) || bo->ttm->caching != ttm_cached) {
> +       if (!i915_ttm_cpu_maps_iomem(bo->resource) &&
> +           bo->ttm->caching == ttm_uncached) {
> +               obj->write_domain = I915_GEM_DOMAIN_CPU;
> +               obj->read_domains = I915_GEM_DOMAIN_CPU;
> +       } else if (i915_ttm_cpu_maps_iomem(bo->resource) ||
> +                bo->ttm->caching != ttm_cached) {
>                 obj->write_domain = I915_GEM_DOMAIN_WC;
>                 obj->read_domains = I915_GEM_DOMAIN_WC;
>         } else {
> diff --git a/drivers/gpu/drm/i915/gt/shmem_utils.c b/drivers/gpu/drm/i915/gt/shmem_utils.c
> index 402f085f3a02..4f842094e484 100644
> --- a/drivers/gpu/drm/i915/gt/shmem_utils.c
> +++ b/drivers/gpu/drm/i915/gt/shmem_utils.c
> @@ -10,6 +10,9 @@
>
>  #include "gem/i915_gem_object.h"
>  #include "gem/i915_gem_lmem.h"
> +#include "gem/i915_gem_ttm.h"
> +
> +#include "i915_drv.h"
>  #include "shmem_utils.h"
>
>  struct file *shmem_create_from_data(const char *name, void *data, size_t len)
> @@ -30,24 +33,65 @@ struct file *shmem_create_from_data(const char *name, void *data, size_t len)
>         return file;
>  }
>
> +static int shmem_flush_object(struct file *file, unsigned long num_pages)
> +{
> +       struct page *page;
> +       unsigned long pfn;
> +
> +       for (pfn = 0; pfn < num_pages; pfn++) {
> +               page = shmem_read_mapping_page_gfp(file->f_mapping, pfn,
> +                                                  GFP_KERNEL);
> +               if (IS_ERR(page))
> +                       return PTR_ERR(page);
> +
> +               set_page_dirty(page);
> +               mark_page_accessed(page);
> +               kunmap(page);
> +               put_page(page);
> +       }
> +
> +       return 0;
> +}
> +
>  struct file *shmem_create_from_object(struct drm_i915_gem_object *obj)
>  {
> +       struct drm_i915_private *i915 = to_i915(obj->base.dev);
>         struct file *file;
>         void *ptr;
> +       int err;
>
>         if (i915_gem_object_is_shmem(obj)) {
> -               file = obj->base.filp;
> -               atomic_long_inc(&file->f_count);
> -               return file;
> -       }
>
> -       ptr = i915_gem_object_pin_map_unlocked(obj, i915_gem_object_is_lmem(obj) ?
> -                                               I915_MAP_WC : I915_MAP_WB);
> -       if (IS_ERR(ptr))
> -               return ERR_CAST(ptr);
> +               GEM_BUG_ON(!i915_gem_object_has_pages(obj));
>
> -       file = shmem_create_from_data("", ptr, obj->base.size);
> -       i915_gem_object_unpin_map(obj);
> +               err = i915_gem_object_pin_pages_unlocked(obj);
> +               if (err) {
> +                       drm_dbg(&i915->drm, "%s pin-pages err=%d\n", __func__,
> +                               err);
> +                       return ERR_PTR(err);
> +               }
> +
> +               file = i915_gem_ttm_get_filep(obj);
> +               GEM_BUG_ON(!file);
> +
> +               err = shmem_flush_object(file, obj->base.size >> PAGE_SHIFT);
> +               if (err) {
> +                       drm_dbg(&i915->drm, "shmem_flush_object failed\n");
> +                       i915_gem_object_unpin_pages(obj);
> +                       return ERR_PTR(err);
> +               }
> +
> +               atomic_long_inc(&file->f_count);
> +               i915_gem_object_unpin_pages(obj);
> +       } else {
> +               ptr = i915_gem_object_pin_map_unlocked(obj, i915_gem_object_is_lmem(obj) ?
> +                                                      I915_MAP_WC : I915_MAP_WB);
> +               if (IS_ERR(ptr))
> +                       return ERR_CAST(ptr);
> +
> +               file = shmem_create_from_data("", ptr, obj->base.size);
> +               i915_gem_object_unpin_map(obj);
> +       }
>
>         return file;
>  }
> diff --git a/drivers/gpu/drm/i915/intel_memory_region.c b/drivers/gpu/drm/i915/intel_memory_region.c
> index e38d2db1c3e3..82b6684d7e60 100644
> --- a/drivers/gpu/drm/i915/intel_memory_region.c
> +++ b/drivers/gpu/drm/i915/intel_memory_region.c
> @@ -309,12 +309,7 @@ int intel_memory_regions_hw_probe(struct drm_i915_private *i915)
>                 instance = intel_region_map[i].instance;
>                 switch (type) {
>                 case INTEL_MEMORY_SYSTEM:
> -                       if (IS_DGFX(i915))
> -                               mem = i915_gem_ttm_system_setup(i915, type,
> -                                                               instance);
> -                       else
> -                               mem = i915_gem_shmem_setup(i915, type,
> -                                                          instance);
> +                       mem = i915_gem_ttm_system_setup(i915, type, instance);
>                         break;
>                 case INTEL_MEMORY_STOLEN_LOCAL:
>                         mem = i915_gem_stolen_lmem_setup(i915, type, instance);
> --
> 2.35.1
>
diff mbox series

Patch

diff --git a/drivers/gpu/drm/i915/gem/i915_gem_dmabuf.c b/drivers/gpu/drm/i915/gem/i915_gem_dmabuf.c
index f5062d0c6333..de04ce4210b3 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_dmabuf.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_dmabuf.c
@@ -12,6 +12,7 @@ 
 #include <asm/smp.h>
 
 #include "gem/i915_gem_dmabuf.h"
+#include "gem/i915_gem_ttm.h"
 #include "i915_drv.h"
 #include "i915_gem_object.h"
 #include "i915_scatterlist.h"
@@ -94,22 +95,25 @@  static int i915_gem_dmabuf_mmap(struct dma_buf *dma_buf, struct vm_area_struct *
 {
 	struct drm_i915_gem_object *obj = dma_buf_to_obj(dma_buf);
 	struct drm_i915_private *i915 = to_i915(obj->base.dev);
+	struct file *filp = i915_gem_ttm_get_filep(obj);
 	int ret;
 
+	GEM_BUG_ON(obj->base.import_attach != NULL);
+
 	if (obj->base.size < vma->vm_end - vma->vm_start)
 		return -EINVAL;
 
 	if (HAS_LMEM(i915))
 		return drm_gem_prime_mmap(&obj->base, vma);
 
-	if (!obj->base.filp)
+	if (!filp)
 		return -ENODEV;
 
-	ret = call_mmap(obj->base.filp, vma);
+	ret = call_mmap(filp, vma);
 	if (ret)
 		return ret;
 
-	vma_set_file(vma, obj->base.filp);
+	vma_set_file(vma, filp);
 
 	return 0;
 }
@@ -224,6 +228,8 @@  struct dma_buf *i915_gem_prime_export(struct drm_gem_object *gem_obj, int flags)
 	exp_info.priv = gem_obj;
 	exp_info.resv = obj->base.resv;
 
+	GEM_BUG_ON(obj->base.import_attach != NULL);
+
 	if (obj->ops->dmabuf_export) {
 		int ret = obj->ops->dmabuf_export(obj);
 		if (ret)
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_mman.c b/drivers/gpu/drm/i915/gem/i915_gem_mman.c
index 0c5c43852e24..d963cf35fdc9 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_mman.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_mman.c
@@ -64,7 +64,9 @@  i915_gem_mmap_ioctl(struct drm_device *dev, void *data,
 	struct drm_i915_private *i915 = to_i915(dev);
 	struct drm_i915_gem_mmap *args = data;
 	struct drm_i915_gem_object *obj;
+	struct file *filp;
 	unsigned long addr;
+	int ret;
 
 	/*
 	 * mmap ioctl is disallowed for all discrete platforms,
@@ -83,12 +85,20 @@  i915_gem_mmap_ioctl(struct drm_device *dev, void *data,
 	if (!obj)
 		return -ENOENT;
 
-	/* prime objects have no backing filp to GEM mmap
-	 * pages from.
-	 */
-	if (!obj->base.filp) {
-		addr = -ENXIO;
-		goto err;
+	if (obj->base.import_attach)
+		filp = obj->base.filp;
+	else {
+		ret = i915_gem_object_pin_pages_unlocked(obj);
+		if (ret) {
+			addr = ret;
+			goto err_pin;
+		}
+
+		filp = i915_gem_ttm_get_filep(obj);
+		if (!filp) {
+			addr = -ENXIO;
+			goto err;
+		}
 	}
 
 	if (range_overflows(args->offset, args->size, (u64)obj->base.size)) {
@@ -96,7 +106,7 @@  i915_gem_mmap_ioctl(struct drm_device *dev, void *data,
 		goto err;
 	}
 
-	addr = vm_mmap(obj->base.filp, 0, args->size,
+	addr = vm_mmap(filp, 0, args->size,
 		       PROT_READ | PROT_WRITE, MAP_SHARED,
 		       args->offset);
 	if (IS_ERR_VALUE(addr))
@@ -111,7 +121,7 @@  i915_gem_mmap_ioctl(struct drm_device *dev, void *data,
 			goto err;
 		}
 		vma = find_vma(mm, addr);
-		if (vma && __vma_matches(vma, obj->base.filp, addr, args->size))
+		if (vma && __vma_matches(vma, filp, addr, args->size))
 			vma->vm_page_prot =
 				pgprot_writecombine(vm_get_page_prot(vma->vm_flags));
 		else
@@ -120,12 +130,18 @@  i915_gem_mmap_ioctl(struct drm_device *dev, void *data,
 		if (IS_ERR_VALUE(addr))
 			goto err;
 	}
+	if (!obj->base.import_attach)
+		i915_gem_object_unpin_pages(obj);
+
 	i915_gem_object_put(obj);
 
 	args->addr_ptr = (u64)addr;
 	return 0;
 
 err:
+	if (!obj->base.import_attach)
+		i915_gem_object_unpin_pages(obj);
+err_pin:
 	i915_gem_object_put(obj);
 	return addr;
 }
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_object.h b/drivers/gpu/drm/i915/gem/i915_gem_object.h
index e11d82a9f7c3..a12f2733075a 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_object.h
+++ b/drivers/gpu/drm/i915/gem/i915_gem_object.h
@@ -592,7 +592,7 @@  i915_gem_object_invalidate_frontbuffer(struct drm_i915_gem_object *obj,
 
 int i915_gem_object_read_from_page(struct drm_i915_gem_object *obj, u64 offset, void *dst, int size);
 
-bool i915_gem_object_is_shmem(const struct drm_i915_gem_object *obj);
+bool i915_gem_object_is_shmem(struct drm_i915_gem_object *obj);
 
 void __i915_gem_free_object_rcu(struct rcu_head *head);
 
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_phys.c b/drivers/gpu/drm/i915/gem/i915_gem_phys.c
index 0d0e46dae559..af3c1c43000c 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_phys.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_phys.c
@@ -11,6 +11,7 @@ 
 #include <drm/drm_cache.h>
 
 #include "gt/intel_gt.h"
+#include "gem/i915_gem_ttm.h"
 #include "i915_drv.h"
 #include "i915_gem_object.h"
 #include "i915_gem_region.h"
@@ -19,7 +20,7 @@ 
 
 static int i915_gem_object_get_pages_phys(struct drm_i915_gem_object *obj)
 {
-	struct address_space *mapping = obj->base.filp->f_mapping;
+	struct address_space *mapping = i915_gem_ttm_get_filep(obj)->f_mapping;
 	struct drm_i915_private *i915 = to_i915(obj->base.dev);
 	struct scatterlist *sg;
 	struct sg_table *st;
@@ -28,6 +29,8 @@  static int i915_gem_object_get_pages_phys(struct drm_i915_gem_object *obj)
 	void *dst;
 	int i;
 
+	GEM_BUG_ON(obj->base.import_attach != NULL);
+
 	if (GEM_WARN_ON(i915_gem_object_needs_bit17_swizzle(obj)))
 		return -EINVAL;
 
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_shmem.c b/drivers/gpu/drm/i915/gem/i915_gem_shmem.c
index c2a3e388fcb4..343eb5897a36 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_shmem.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_shmem.c
@@ -11,12 +11,14 @@ 
 #include <drm/drm_cache.h>
 
 #include "gem/i915_gem_region.h"
+#include "gem/i915_gem_ttm.h"
 #include "i915_drv.h"
 #include "i915_gem_object.h"
 #include "i915_gem_tiling.h"
 #include "i915_gemfs.h"
 #include "i915_scatterlist.h"
 #include "i915_trace.h"
+#include "i915_gem_clflush.h"
 
 /*
  * Move pages to appropriate lru and release the pagevec, decrementing the
@@ -188,105 +190,6 @@  int shmem_sg_alloc_table(struct drm_i915_private *i915, struct sg_table *st,
 	return ret;
 }
 
-static int shmem_get_pages(struct drm_i915_gem_object *obj)
-{
-	struct drm_i915_private *i915 = to_i915(obj->base.dev);
-	struct intel_memory_region *mem = obj->mm.region;
-	struct address_space *mapping = obj->base.filp->f_mapping;
-	const unsigned long page_count = obj->base.size / PAGE_SIZE;
-	unsigned int max_segment = i915_sg_segment_size();
-	struct sg_table *st;
-	struct sgt_iter sgt_iter;
-	struct page *page;
-	int ret;
-
-	/*
-	 * Assert that the object is not currently in any GPU domain. As it
-	 * wasn't in the GTT, there shouldn't be any way it could have been in
-	 * a GPU cache
-	 */
-	GEM_BUG_ON(obj->read_domains & I915_GEM_GPU_DOMAINS);
-	GEM_BUG_ON(obj->write_domain & I915_GEM_GPU_DOMAINS);
-
-rebuild_st:
-	st = kmalloc(sizeof(*st), GFP_KERNEL);
-	if (!st)
-		return -ENOMEM;
-
-	ret = shmem_sg_alloc_table(i915, st, obj->base.size, mem, mapping,
-				   max_segment);
-	if (ret)
-		goto err_st;
-
-	ret = i915_gem_gtt_prepare_pages(obj, st);
-	if (ret) {
-		/*
-		 * DMA remapping failed? One possible cause is that
-		 * it could not reserve enough large entries, asking
-		 * for PAGE_SIZE chunks instead may be helpful.
-		 */
-		if (max_segment > PAGE_SIZE) {
-			for_each_sgt_page(page, sgt_iter, st)
-				put_page(page);
-			sg_free_table(st);
-			kfree(st);
-
-			max_segment = PAGE_SIZE;
-			goto rebuild_st;
-		} else {
-			dev_warn(i915->drm.dev,
-				 "Failed to DMA remap %lu pages\n",
-				 page_count);
-			goto err_pages;
-		}
-	}
-
-	if (i915_gem_object_needs_bit17_swizzle(obj))
-		i915_gem_object_do_bit_17_swizzle(obj, st);
-
-	if (i915_gem_object_can_bypass_llc(obj))
-		obj->cache_dirty = true;
-
-	__i915_gem_object_set_pages(obj, st, i915_sg_dma_sizes(st->sgl));
-
-	return 0;
-
-err_pages:
-	shmem_sg_free_table(st, mapping, false, false);
-	/*
-	 * shmemfs first checks if there is enough memory to allocate the page
-	 * and reports ENOSPC should there be insufficient, along with the usual
-	 * ENOMEM for a genuine allocation failure.
-	 *
-	 * We use ENOSPC in our driver to mean that we have run out of aperture
-	 * space and so want to translate the error from shmemfs back to our
-	 * usual understanding of ENOMEM.
-	 */
-err_st:
-	if (ret == -ENOSPC)
-		ret = -ENOMEM;
-
-	kfree(st);
-
-	return ret;
-}
-
-static int
-shmem_truncate(struct drm_i915_gem_object *obj)
-{
-	/*
-	 * Our goal here is to return as much of the memory as
-	 * is possible back to the system as we are called from OOM.
-	 * To do this we must instruct the shmfs to drop all of its
-	 * backing pages, *now*.
-	 */
-	shmem_truncate_range(file_inode(obj->base.filp), 0, (loff_t)-1);
-	obj->mm.madv = __I915_MADV_PURGED;
-	obj->mm.pages = ERR_PTR(-EFAULT);
-
-	return 0;
-}
-
 void __shmem_writeback(size_t size, struct address_space *mapping)
 {
 	struct writeback_control wbc = {
@@ -329,27 +232,6 @@  void __shmem_writeback(size_t size, struct address_space *mapping)
 	}
 }
 
-static void
-shmem_writeback(struct drm_i915_gem_object *obj)
-{
-	__shmem_writeback(obj->base.size, obj->base.filp->f_mapping);
-}
-
-static int shmem_shrink(struct drm_i915_gem_object *obj, unsigned int flags)
-{
-	switch (obj->mm.madv) {
-	case I915_MADV_DONTNEED:
-		return i915_gem_object_truncate(obj);
-	case __I915_MADV_PURGED:
-		return 0;
-	}
-
-	if (flags & I915_GEM_OBJECT_SHRINK_WRITEBACK)
-		shmem_writeback(obj);
-
-	return 0;
-}
-
 void
 __i915_gem_object_release_shmem(struct drm_i915_gem_object *obj,
 				struct sg_table *pages,
@@ -395,220 +277,6 @@  void i915_gem_object_put_pages_shmem(struct drm_i915_gem_object *obj, struct sg_
 	obj->mm.dirty = false;
 }
 
-static void
-shmem_put_pages(struct drm_i915_gem_object *obj, struct sg_table *pages)
-{
-	if (likely(i915_gem_object_has_struct_page(obj)))
-		i915_gem_object_put_pages_shmem(obj, pages);
-	else
-		i915_gem_object_put_pages_phys(obj, pages);
-}
-
-static int
-shmem_pwrite(struct drm_i915_gem_object *obj,
-	     const struct drm_i915_gem_pwrite *arg)
-{
-	struct address_space *mapping = obj->base.filp->f_mapping;
-	char __user *user_data = u64_to_user_ptr(arg->data_ptr);
-	u64 remain, offset;
-	unsigned int pg;
-
-	/* Caller already validated user args */
-	GEM_BUG_ON(!access_ok(user_data, arg->size));
-
-	if (!i915_gem_object_has_struct_page(obj))
-		return i915_gem_object_pwrite_phys(obj, arg);
-
-	/*
-	 * Before we instantiate/pin the backing store for our use, we
-	 * can prepopulate the shmemfs filp efficiently using a write into
-	 * the pagecache. We avoid the penalty of instantiating all the
-	 * pages, important if the user is just writing to a few and never
-	 * uses the object on the GPU, and using a direct write into shmemfs
-	 * allows it to avoid the cost of retrieving a page (either swapin
-	 * or clearing-before-use) before it is overwritten.
-	 */
-	if (i915_gem_object_has_pages(obj))
-		return -ENODEV;
-
-	if (obj->mm.madv != I915_MADV_WILLNEED)
-		return -EFAULT;
-
-	/*
-	 * Before the pages are instantiated the object is treated as being
-	 * in the CPU domain. The pages will be clflushed as required before
-	 * use, and we can freely write into the pages directly. If userspace
-	 * races pwrite with any other operation; corruption will ensue -
-	 * that is userspace's prerogative!
-	 */
-
-	remain = arg->size;
-	offset = arg->offset;
-	pg = offset_in_page(offset);
-
-	do {
-		unsigned int len, unwritten;
-		struct page *page;
-		void *data, *vaddr;
-		int err;
-		char c;
-
-		len = PAGE_SIZE - pg;
-		if (len > remain)
-			len = remain;
-
-		/* Prefault the user page to reduce potential recursion */
-		err = __get_user(c, user_data);
-		if (err)
-			return err;
-
-		err = __get_user(c, user_data + len - 1);
-		if (err)
-			return err;
-
-		err = pagecache_write_begin(obj->base.filp, mapping,
-					    offset, len, 0,
-					    &page, &data);
-		if (err < 0)
-			return err;
-
-		vaddr = kmap_atomic(page);
-		unwritten = __copy_from_user_inatomic(vaddr + pg,
-						      user_data,
-						      len);
-		kunmap_atomic(vaddr);
-
-		err = pagecache_write_end(obj->base.filp, mapping,
-					  offset, len, len - unwritten,
-					  page, data);
-		if (err < 0)
-			return err;
-
-		/* We don't handle -EFAULT, leave it to the caller to check */
-		if (unwritten)
-			return -ENODEV;
-
-		remain -= len;
-		user_data += len;
-		offset += len;
-		pg = 0;
-	} while (remain);
-
-	return 0;
-}
-
-static int
-shmem_pread(struct drm_i915_gem_object *obj,
-	    const struct drm_i915_gem_pread *arg)
-{
-	if (!i915_gem_object_has_struct_page(obj))
-		return i915_gem_object_pread_phys(obj, arg);
-
-	return -ENODEV;
-}
-
-static void shmem_release(struct drm_i915_gem_object *obj)
-{
-	if (i915_gem_object_has_struct_page(obj))
-		i915_gem_object_release_memory_region(obj);
-
-	fput(obj->base.filp);
-}
-
-const struct drm_i915_gem_object_ops i915_gem_shmem_ops = {
-	.name = "i915_gem_object_shmem",
-	.flags = I915_GEM_OBJECT_IS_SHRINKABLE,
-
-	.get_pages = shmem_get_pages,
-	.put_pages = shmem_put_pages,
-	.truncate = shmem_truncate,
-	.shrink = shmem_shrink,
-
-	.pwrite = shmem_pwrite,
-	.pread = shmem_pread,
-
-	.release = shmem_release,
-};
-
-static int __create_shmem(struct drm_i915_private *i915,
-			  struct drm_gem_object *obj,
-			  resource_size_t size)
-{
-	unsigned long flags = VM_NORESERVE;
-	struct file *filp;
-
-	drm_gem_private_object_init(&i915->drm, obj, size);
-
-	if (i915->mm.gemfs)
-		filp = shmem_file_setup_with_mnt(i915->mm.gemfs, "i915", size,
-						 flags);
-	else
-		filp = shmem_file_setup("i915", size, flags);
-	if (IS_ERR(filp))
-		return PTR_ERR(filp);
-
-	obj->filp = filp;
-	return 0;
-}
-
-static int shmem_object_init(struct intel_memory_region *mem,
-			     struct drm_i915_gem_object *obj,
-			     resource_size_t offset,
-			     resource_size_t size,
-			     resource_size_t page_size,
-			     unsigned int flags)
-{
-	static struct lock_class_key lock_class;
-	struct drm_i915_private *i915 = mem->i915;
-	struct address_space *mapping;
-	unsigned int cache_level;
-	gfp_t mask;
-	int ret;
-
-	ret = __create_shmem(i915, &obj->base, size);
-	if (ret)
-		return ret;
-
-	mask = GFP_HIGHUSER | __GFP_RECLAIMABLE;
-	if (IS_I965GM(i915) || IS_I965G(i915)) {
-		/* 965gm cannot relocate objects above 4GiB. */
-		mask &= ~__GFP_HIGHMEM;
-		mask |= __GFP_DMA32;
-	}
-
-	mapping = obj->base.filp->f_mapping;
-	mapping_set_gfp_mask(mapping, mask);
-	GEM_BUG_ON(!(mapping_gfp_mask(mapping) & __GFP_RECLAIM));
-
-	i915_gem_object_init(obj, &i915_gem_shmem_ops, &lock_class, 0);
-	obj->mem_flags |= I915_BO_FLAG_STRUCT_PAGE;
-	obj->write_domain = I915_GEM_DOMAIN_CPU;
-	obj->read_domains = I915_GEM_DOMAIN_CPU;
-
-	if (HAS_LLC(i915))
-		/* On some devices, we can have the GPU use the LLC (the CPU
-		 * cache) for about a 10% performance improvement
-		 * compared to uncached.  Graphics requests other than
-		 * display scanout are coherent with the CPU in
-		 * accessing this cache.  This means in this mode we
-		 * don't need to clflush on the CPU side, and on the
-		 * GPU side we only need to flush internal caches to
-		 * get data visible to the CPU.
-		 *
-		 * However, we maintain the display planes as UC, and so
-		 * need to rebind when first used as such.
-		 */
-		cache_level = I915_CACHE_LLC;
-	else
-		cache_level = I915_CACHE_NONE;
-
-	i915_gem_object_set_cache_coherency(obj, cache_level);
-
-	i915_gem_object_init_memory_region(obj, mem);
-
-	return 0;
-}
-
 struct drm_i915_gem_object *
 i915_gem_object_create_shmem(struct drm_i915_private *i915,
 			     resource_size_t size)
@@ -634,7 +302,19 @@  i915_gem_object_create_shmem_from_data(struct drm_i915_private *dev_priv,
 
 	GEM_BUG_ON(obj->write_domain != I915_GEM_DOMAIN_CPU);
 
-	file = obj->base.filp;
+	/*
+	 *  When using TTM as the main GEM backend, we need to pin the pages
+	 *  after creating the object to access the file pointer
+	 */
+	err = i915_gem_object_pin_pages_unlocked(obj);
+	if (err) {
+		drm_dbg(&dev_priv->drm, "%s pin-pages err=%d\n", __func__, err);
+		goto fail_pin;
+	}
+
+	file = i915_gem_ttm_get_filep(obj);
+	GEM_WARN_ON(file == NULL);
+
 	offset = 0;
 	do {
 		unsigned int len = min_t(typeof(size), size, PAGE_SIZE);
@@ -662,51 +342,14 @@  i915_gem_object_create_shmem_from_data(struct drm_i915_private *dev_priv,
 		offset += len;
 	} while (size);
 
+	i915_gem_clflush_object(obj, I915_CLFLUSH_SYNC);
+	i915_gem_object_unpin_pages(obj);
+
 	return obj;
 
 fail:
+	i915_gem_object_unpin_pages(obj);
+fail_pin:
 	i915_gem_object_put(obj);
 	return ERR_PTR(err);
 }
-
-static int init_shmem(struct intel_memory_region *mem)
-{
-	int err;
-
-	err = i915_gemfs_init(mem->i915);
-	if (err) {
-		DRM_NOTE("Unable to create a private tmpfs mount, hugepage support will be disabled(%d).\n",
-			 err);
-	}
-
-	intel_memory_region_set_name(mem, "system");
-
-	return 0; /* Don't error, we can simply fallback to the kernel mnt */
-}
-
-static int release_shmem(struct intel_memory_region *mem)
-{
-	i915_gemfs_fini(mem->i915);
-	return 0;
-}
-
-static const struct intel_memory_region_ops shmem_region_ops = {
-	.init = init_shmem,
-	.release = release_shmem,
-	.init_object = shmem_object_init,
-};
-
-struct intel_memory_region *i915_gem_shmem_setup(struct drm_i915_private *i915,
-						 u16 type, u16 instance)
-{
-	return intel_memory_region_create(i915, 0,
-					  totalram_pages() << PAGE_SHIFT,
-					  PAGE_SIZE, 0, 0,
-					  type, instance,
-					  &shmem_region_ops);
-}
-
-bool i915_gem_object_is_shmem(const struct drm_i915_gem_object *obj)
-{
-	return obj->ops == &i915_gem_shmem_ops;
-}
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_ttm.c b/drivers/gpu/drm/i915/gem/i915_gem_ttm.c
index 4c25d9b2f138..e4f3a467abd8 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_ttm.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_ttm.c
@@ -21,6 +21,7 @@ 
 #include "gem/i915_gem_ttm_move.h"
 #include "gem/i915_gem_ttm_pm.h"
 #include "gt/intel_gpu_commands.h"
+#include "gem/i915_gem_tiling.h"
 
 #define I915_TTM_PRIO_PURGE     0
 #define I915_TTM_PRIO_NO_PAGES  1
@@ -37,6 +38,7 @@ 
  * @ttm: The base TTM page vector.
  * @dev: The struct device used for dma mapping and unmapping.
  * @cached_rsgt: The cached scatter-gather table.
+ * @bo: TTM buffer object this ttm_tt structure is bound to.
  * @is_shmem: Set if using shmem.
  * @filp: The shmem file, if using shmem backend.
  *
@@ -50,6 +52,7 @@  struct i915_ttm_tt {
 	struct ttm_tt ttm;
 	struct device *dev;
 	struct i915_refct_sgt cached_rsgt;
+	struct ttm_buffer_object *bo;
 
 	bool is_shmem;
 	struct file *filp;
@@ -113,6 +116,10 @@  static int i915_ttm_err_to_gem(int err)
 static enum ttm_caching
 i915_ttm_select_tt_caching(const struct drm_i915_gem_object *obj)
 {
+	struct drm_i915_private *i915 = to_i915(obj->base.dev);
+
+	if (GRAPHICS_VER(i915) <= 5)
+		return ttm_uncached;
 	/*
 	 * Objects only allowed in system get cached cpu-mappings, or when
 	 * evicting lmem-only buffers to system for swapping. Other objects get
@@ -207,6 +214,11 @@  static int i915_ttm_tt_shmem_populate(struct ttm_device *bdev,
 			return PTR_ERR(filp);
 
 		mask = GFP_HIGHUSER | __GFP_RECLAIMABLE;
+		if (IS_I965GM(i915) || IS_I965G(i915)) {
+			/* 965gm cannot relocate objects above 4GiB. */
+			mask &= ~__GFP_HIGHMEM;
+			mask |= __GFP_DMA32;
+		}
 
 		mapping = filp->f_mapping;
 		mapping_set_gfp_mask(mapping, mask);
@@ -304,12 +316,14 @@  static struct ttm_tt *i915_ttm_tt_create(struct ttm_buffer_object *bo,
 	if (!i915_tt)
 		return NULL;
 
+	i915_tt->bo = bo;
+
 	if (obj->flags & I915_BO_ALLOC_CPU_CLEAR &&
 	    man->use_tt)
 		page_flags |= TTM_TT_FLAG_ZERO_ALLOC;
 
 	caching = i915_ttm_select_tt_caching(obj);
-	if (i915_gem_object_is_shrinkable(obj) && caching == ttm_cached) {
+	if (i915_gem_object_is_shrinkable(obj) && (caching != ttm_write_combined)) {
 		page_flags |= TTM_TT_FLAG_EXTERNAL |
 			      TTM_TT_FLAG_EXTERNAL_MAPPABLE;
 		i915_tt->is_shmem = true;
@@ -352,11 +366,19 @@  static void i915_ttm_tt_unpopulate(struct ttm_device *bdev, struct ttm_tt *ttm)
 {
 	struct i915_ttm_tt *i915_tt = container_of(ttm, typeof(*i915_tt), ttm);
 	struct sg_table *st = &i915_tt->cached_rsgt.table;
+	struct ttm_buffer_object *bo = i915_tt->bo;
+	struct drm_i915_gem_object *obj = i915_ttm_to_gem(bo);
+
+	if (i915_tt->is_shmem)
+		__i915_gem_object_release_shmem(obj, st, true);
 
 	if (st->sgl)
 		dma_unmap_sgtable(i915_tt->dev, st, DMA_BIDIRECTIONAL, 0);
 
 	if (i915_tt->is_shmem) {
+		if (i915_gem_object_needs_bit17_swizzle(obj))
+			i915_gem_object_save_bit_17_swizzle(obj, st);
+
 		i915_ttm_tt_shmem_unpopulate(ttm);
 	} else {
 		sg_free_table(st);
@@ -798,6 +820,12 @@  static int __i915_ttm_get_pages(struct drm_i915_gem_object *obj,
 		obj->mm.rsgt = rsgt;
 		__i915_gem_object_set_pages(obj, &rsgt->table,
 					    i915_sg_dma_sizes(rsgt->table.sgl));
+
+		if (i915_gem_object_needs_bit17_swizzle(obj))
+			i915_gem_object_save_bit_17_swizzle(obj, &rsgt->table);
+
+		if (i915_gem_object_can_bypass_llc(obj))
+			obj->cache_dirty = true;
 	}
 
 	GEM_BUG_ON(bo->ttm && ((obj->base.size >> PAGE_SHIFT) < bo->ttm->num_pages));
@@ -979,6 +1007,119 @@  void i915_ttm_adjust_lru(struct drm_i915_gem_object *obj)
 	spin_unlock(&bo->bdev->lru_lock);
 }
 
+static int
+i915_ttm_pwrite(struct drm_i915_gem_object *obj,
+		const struct drm_i915_gem_pwrite *arg)
+{
+	struct drm_i915_private *i915 = to_i915(obj->base.dev);
+	char __user *user_data = u64_to_user_ptr(arg->data_ptr);
+	struct address_space *mapping;
+	u64 remain, offset;
+	struct file *filp;
+	unsigned int pg;
+	int err;
+
+	/* Caller already validated user args */
+	GEM_BUG_ON(!access_ok(user_data, arg->size));
+
+	if (!i915_gem_object_has_struct_page(obj))
+		return i915_gem_object_pwrite_phys(obj, arg);
+
+	/*
+	 * We need to pin the pages in order to have access to the filp
+	 * given by shmem, quite unlike in the legacy GEM shmem backend
+	 * where it would be available upon object creation
+	 */
+	err = i915_gem_object_pin_pages_unlocked(obj);
+	if (err) {
+		drm_dbg(&i915->drm, "%s pin-pages err=%d\n", __func__, err);
+		return err;
+	}
+
+	filp = i915_gem_ttm_get_filep(obj);
+	if (!filp) {
+		err = -ENXIO;
+		goto error;
+	}
+
+	mapping = filp->f_mapping;
+
+	if (obj->mm.madv != I915_MADV_WILLNEED) {
+		err = -EFAULT;
+		goto error;
+	}
+
+	/*
+	 * Before the pages are instantiated the object is treated as being
+	 * in the CPU domain. The pages will be clflushed as required before
+	 * use, and we can freely write into the pages directly. If userspace
+	 * races pwrite with any other operation; corruption will ensue -
+	 * that is userspace's prerogative!
+	 */
+
+	remain = arg->size;
+	offset = arg->offset;
+	pg = offset_in_page(offset);
+
+	do {
+		unsigned int len, unwritten;
+		struct page *page;
+		void *data, *vaddr;
+		int err;
+		char c;
+
+		len = PAGE_SIZE - pg;
+		if (len > remain)
+			len = remain;
+
+		/* Prefault the user page to reduce potential recursion */
+		err = __get_user(c, user_data);
+		if (err)
+			goto error;
+
+		err = __get_user(c, user_data + len - 1);
+		if (err)
+			goto error;
+
+		err = pagecache_write_begin(obj->base.filp, mapping,
+					    offset, len, 0,
+					    &page, &data);
+		if (err < 0)
+			goto error;
+
+		vaddr = kmap_atomic(page);
+		unwritten = __copy_from_user_inatomic(vaddr + pg,
+						      user_data,
+						      len);
+		kunmap_atomic(vaddr);
+
+		err = pagecache_write_end(obj->base.filp, mapping,
+					  offset, len, len - unwritten,
+					  page, data);
+		if (err < 0)
+			goto error;
+
+		/* We don't handle -EFAULT, leave it to the caller to check */
+		if (unwritten) {
+			err = -ENODEV;
+			goto error;
+		}
+
+		remain -= len;
+		user_data += len;
+		offset += len;
+		pg = 0;
+	} while (remain);
+
+	i915_gem_object_unpin_pages(obj);
+
+	return 0;
+
+error:
+	i915_gem_object_unpin_pages(obj);
+	return err;
+}
+
 /*
  * TTM-backed gem object destruction requires some clarification.
  * Basically we have two possibilities here. We can either rely on the
@@ -1120,7 +1261,7 @@  static void i915_ttm_unmap_virtual(struct drm_i915_gem_object *obj)
 	ttm_bo_unmap_virtual(i915_gem_to_ttm(obj));
 }
 
-static const struct drm_i915_gem_object_ops i915_gem_ttm_obj_ops = {
+static const struct drm_i915_gem_object_ops i915_gem_ttm_discrete_ops = {
 	.name = "i915_gem_object_ttm",
 	.flags = I915_GEM_OBJECT_IS_SHRINKABLE |
 		 I915_GEM_OBJECT_SELF_MANAGED_SHRINK_LIST,
@@ -1139,6 +1280,22 @@  static const struct drm_i915_gem_object_ops i915_gem_ttm_obj_ops = {
 	.mmap_ops = &vm_ops_ttm,
 };
 
+static const struct drm_i915_gem_object_ops i915_gem_ttm_obj_integrated_ops = {
+	.name = "i915_gem_object_ttm",
+	.flags = I915_GEM_OBJECT_IS_SHRINKABLE |
+		 I915_GEM_OBJECT_SELF_MANAGED_SHRINK_LIST,
+
+	.get_pages = i915_ttm_get_pages,
+	.put_pages = i915_ttm_put_pages,
+	.truncate = i915_ttm_truncate,
+	.shrink = i915_ttm_shrink,
+
+	.pwrite = i915_ttm_pwrite,
+
+	.adjust_lru = i915_ttm_adjust_lru,
+	.delayed_free = i915_ttm_delayed_free,
+};
+
 void i915_ttm_bo_destroy(struct ttm_buffer_object *bo)
 {
 	struct drm_i915_gem_object *obj = i915_ttm_to_gem(bo);
@@ -1196,7 +1353,12 @@  int __i915_gem_ttm_object_init(struct intel_memory_region *mem,
 	int ret;
 
 	drm_gem_private_object_init(&i915->drm, &obj->base, size);
-	i915_gem_object_init(obj, &i915_gem_ttm_obj_ops, &lock_class, flags);
+
+	if (IS_DGFX(i915))
+		i915_gem_object_init(obj, &i915_gem_ttm_discrete_ops, &lock_class, flags);
+	else
+		i915_gem_object_init(obj, &i915_gem_ttm_obj_integrated_ops, &lock_class,
+				     flags);
 
 	obj->bo_offset = offset;
 
@@ -1206,8 +1368,8 @@  int __i915_gem_ttm_object_init(struct intel_memory_region *mem,
 
 	INIT_RADIX_TREE(&obj->ttm.get_io_page.radix, GFP_KERNEL | __GFP_NOWARN);
 	mutex_init(&obj->ttm.get_io_page.lock);
-	bo_type = (obj->flags & I915_BO_ALLOC_USER) ? ttm_bo_type_device :
-		ttm_bo_type_kernel;
+	bo_type = (obj->ops->mmap_offset && (obj->flags & I915_BO_ALLOC_USER)) ?
+		ttm_bo_type_device : ttm_bo_type_kernel;
 
 	obj->base.vma_node.driver_private = i915_gem_to_ttm(obj);
 
@@ -1251,6 +1413,27 @@  static const struct intel_memory_region_ops ttm_system_region_ops = {
 	.release = intel_region_ttm_fini,
 };
 
+/**
+ * Return: filp.
+ */
+struct file *
+i915_gem_ttm_get_filep(struct drm_i915_gem_object *obj)
+{
+	struct drm_device *dev = obj->base.dev;
+	struct ttm_buffer_object *bo;
+	struct i915_ttm_tt *i915_tt;
+
+	bo = i915_gem_to_ttm(obj);
+	if (!bo->ttm) {
+		drm_dbg(dev, "ttm has not been allocated for bo\n");
+		return NULL;
+	}
+
+	i915_tt = container_of(bo->ttm, typeof(*i915_tt), ttm);
+
+	return i915_tt->filp;
+}
+
 struct intel_memory_region *
 i915_gem_ttm_system_setup(struct drm_i915_private *i915,
 			  u16 type, u16 instance)
@@ -1268,3 +1451,22 @@  i915_gem_ttm_system_setup(struct drm_i915_private *i915,
 	intel_memory_region_set_name(mr, "system-ttm");
 	return mr;
 }
+
+bool i915_gem_object_is_shmem(struct drm_i915_gem_object *obj)
+{
+	struct intel_memory_region *mr = READ_ONCE(obj->mm.region);
+
+#ifdef CONFIG_LOCKDEP
+	if (i915_gem_object_migratable(obj) &&
+	    i915_gem_object_evictable(obj))
+		assert_object_held(obj);
+#endif
+
+	/* Review list of placements to make sure object isn't migratable */
+	if (i915_gem_object_placement_possible(obj, INTEL_MEMORY_LOCAL))
+		return false;
+
+	return mr && (mr->type == INTEL_MEMORY_SYSTEM &&
+		      (obj->ops == &i915_gem_ttm_obj_integrated_ops ||
+		       obj->ops == &i915_gem_ttm_discrete_ops));
+}
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_ttm.h b/drivers/gpu/drm/i915/gem/i915_gem_ttm.h
index 73e371aa3850..f00f18db5a8b 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_ttm.h
+++ b/drivers/gpu/drm/i915/gem/i915_gem_ttm.h
@@ -92,4 +92,7 @@  static inline bool i915_ttm_cpu_maps_iomem(struct ttm_resource *mem)
 	/* Once / if we support GGTT, this is also false for cached ttm_tts */
 	return mem->mem_type != I915_PL_SYSTEM;
 }
+
+struct file *i915_gem_ttm_get_filep(struct drm_i915_gem_object *obj);
+
 #endif
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_ttm_move.c b/drivers/gpu/drm/i915/gem/i915_gem_ttm_move.c
index a10716f4e717..c588e31aa479 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_ttm_move.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_ttm_move.c
@@ -46,6 +46,10 @@  static enum i915_cache_level
 i915_ttm_cache_level(struct drm_i915_private *i915, struct ttm_resource *res,
 		     struct ttm_tt *ttm)
 {
+
+	if (GRAPHICS_VER(i915) <= 5)
+		return I915_CACHE_NONE;
+
 	return ((HAS_LLC(i915) || HAS_SNOOP(i915)) &&
 		!i915_ttm_gtt_binds_lmem(res) &&
 		ttm->caching == ttm_cached) ? I915_CACHE_LLC :
@@ -77,7 +81,12 @@  void i915_ttm_adjust_domains_after_move(struct drm_i915_gem_object *obj)
 {
 	struct ttm_buffer_object *bo = i915_gem_to_ttm(obj);
 
-	if (i915_ttm_cpu_maps_iomem(bo->resource) || bo->ttm->caching != ttm_cached) {
+	if (!i915_ttm_cpu_maps_iomem(bo->resource) &&
+	    bo->ttm->caching == ttm_uncached) {
+		obj->write_domain = I915_GEM_DOMAIN_CPU;
+		obj->read_domains = I915_GEM_DOMAIN_CPU;
+	} else if (i915_ttm_cpu_maps_iomem(bo->resource) ||
+		 bo->ttm->caching != ttm_cached) {
 		obj->write_domain = I915_GEM_DOMAIN_WC;
 		obj->read_domains = I915_GEM_DOMAIN_WC;
 	} else {
diff --git a/drivers/gpu/drm/i915/gt/shmem_utils.c b/drivers/gpu/drm/i915/gt/shmem_utils.c
index 402f085f3a02..4f842094e484 100644
--- a/drivers/gpu/drm/i915/gt/shmem_utils.c
+++ b/drivers/gpu/drm/i915/gt/shmem_utils.c
@@ -10,6 +10,9 @@ 
 
 #include "gem/i915_gem_object.h"
 #include "gem/i915_gem_lmem.h"
+#include "gem/i915_gem_ttm.h"
+
+#include "i915_drv.h"
 #include "shmem_utils.h"
 
 struct file *shmem_create_from_data(const char *name, void *data, size_t len)
@@ -30,24 +33,65 @@  struct file *shmem_create_from_data(const char *name, void *data, size_t len)
 	return file;
 }
 
+static int shmem_flush_object(struct file *file, unsigned long num_pages)
+{
+	struct page *page;
+	unsigned long pfn;
+
+	for (pfn = 0; pfn < num_pages; pfn++) {
+		page = shmem_read_mapping_page_gfp(file->f_mapping, pfn,
+						   GFP_KERNEL);
+		if (IS_ERR(page))
+			return PTR_ERR(page);
+
+		set_page_dirty(page);
+		mark_page_accessed(page);
+		kunmap(page);
+		put_page(page);
+	}
+
+	return 0;
+}
+
 struct file *shmem_create_from_object(struct drm_i915_gem_object *obj)
 {
+	struct drm_i915_private *i915 = to_i915(obj->base.dev);
 	struct file *file;
 	void *ptr;
+	int err;
 
 	if (i915_gem_object_is_shmem(obj)) {
-		file = obj->base.filp;
-		atomic_long_inc(&file->f_count);
-		return file;
-	}
 
-	ptr = i915_gem_object_pin_map_unlocked(obj, i915_gem_object_is_lmem(obj) ?
-						I915_MAP_WC : I915_MAP_WB);
-	if (IS_ERR(ptr))
-		return ERR_CAST(ptr);
+		GEM_BUG_ON(!i915_gem_object_has_pages(obj));
 
-	file = shmem_create_from_data("", ptr, obj->base.size);
-	i915_gem_object_unpin_map(obj);
+		err = i915_gem_object_pin_pages_unlocked(obj);
+		if (err) {
+			drm_dbg(&i915->drm, "%s pin-pages err=%d\n", __func__,
+				err);
+			return ERR_PTR(err);
+		}
+
+		file = i915_gem_ttm_get_filep(obj);
+		GEM_BUG_ON(!file);
+
+		err = shmem_flush_object(file, obj->base.size >> PAGE_SHIFT);
+		if (err) {
+			drm_dbg(&i915->drm, "shmem_flush_object failed\n");
+			i915_gem_object_unpin_pages(obj);
+			return ERR_PTR(err);
+		}
+
+		atomic_long_inc(&file->f_count);
+		i915_gem_object_unpin_pages(obj);
+	} else {
+		ptr = i915_gem_object_pin_map_unlocked(obj, i915_gem_object_is_lmem(obj) ?
+						       I915_MAP_WC : I915_MAP_WB);
+		if (IS_ERR(ptr))
+			return ERR_CAST(ptr);
+
+		file = shmem_create_from_data("", ptr, obj->base.size);
+		i915_gem_object_unpin_map(obj);
+	}
 
 	return file;
 }
diff --git a/drivers/gpu/drm/i915/intel_memory_region.c b/drivers/gpu/drm/i915/intel_memory_region.c
index e38d2db1c3e3..82b6684d7e60 100644
--- a/drivers/gpu/drm/i915/intel_memory_region.c
+++ b/drivers/gpu/drm/i915/intel_memory_region.c
@@ -309,12 +309,7 @@  int intel_memory_regions_hw_probe(struct drm_i915_private *i915)
 		instance = intel_region_map[i].instance;
 		switch (type) {
 		case INTEL_MEMORY_SYSTEM:
-			if (IS_DGFX(i915))
-				mem = i915_gem_ttm_system_setup(i915, type,
-								instance);
-			else
-				mem = i915_gem_shmem_setup(i915, type,
-							   instance);
+			mem = i915_gem_ttm_system_setup(i915, type, instance);
 			break;
 		case INTEL_MEMORY_STOLEN_LOCAL:
 			mem = i915_gem_stolen_lmem_setup(i915, type, instance);