diff options
| author | Andi Shyti <andi.shyti@linux.intel.com> | 2024-08-07 11:05:21 +0100 |
|---|---|---|
| committer | Andi Shyti <andi.shyti@linux.intel.com> | 2024-08-21 15:28:33 +0200 |
| commit | 255fc1703e42321b5afdedc8259ad03c7cc533ec (patch) | |
| tree | bb468d4280bad6b1731df269a4b69b9fca20aa1f | |
| parent | 609d8b1c422cd8d1f93bf526fb236f2e07687e7c (diff) | |
drm/i915/gem: Calculate object page offset for partial memory mapping
To enable partial memory mapping of GPU virtual memory, it's
necessary to introduce an offset to the object's memory
(obj->mm.pages) scatterlist. This adjustment compensates for
instances when userspace mappings do not start from the beginning
of the object.
Based on a patch by Chris Wilson.
Signed-off-by: Andi Shyti <andi.shyti@linux.intel.com>
Cc: Chris Wilson <chris.p.wilson@linux.intel.com>
Cc: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Reviewed-by: Nirmoy Das <nirmoy.das@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240807100521.478266-3-andi.shyti@linux.intel.com
| -rw-r--r-- | drivers/gpu/drm/i915/gem/i915_gem_mman.c | 4 | ||||
| -rw-r--r-- | drivers/gpu/drm/i915/i915_mm.c | 12 | ||||
| -rw-r--r-- | drivers/gpu/drm/i915/i915_mm.h | 3 |
3 files changed, 16 insertions, 3 deletions
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_mman.c b/drivers/gpu/drm/i915/gem/i915_gem_mman.c index 99fde0a05632..21274aa9bddd 100644 --- a/drivers/gpu/drm/i915/gem/i915_gem_mman.c +++ b/drivers/gpu/drm/i915/gem/i915_gem_mman.c @@ -252,6 +252,7 @@ static vm_fault_t vm_fault_cpu(struct vm_fault *vmf) struct vm_area_struct *area = vmf->vma; struct i915_mmap_offset *mmo = area->vm_private_data; struct drm_i915_gem_object *obj = mmo->obj; + unsigned long obj_offset; resource_size_t iomap; int err; @@ -273,10 +274,11 @@ static vm_fault_t vm_fault_cpu(struct vm_fault *vmf) iomap -= obj->mm.region->region.start; } + obj_offset = area->vm_pgoff - drm_vma_node_start(&mmo->vma_node); /* PTEs are revoked in obj->ops->put_pages() */ err = remap_io_sg(area, area->vm_start, area->vm_end - area->vm_start, - obj->mm.pages->sgl, iomap); + obj->mm.pages->sgl, obj_offset, iomap); if (area->vm_flags & VM_WRITE) { GEM_BUG_ON(!i915_gem_object_has_pinned_pages(obj)); diff --git a/drivers/gpu/drm/i915/i915_mm.c b/drivers/gpu/drm/i915/i915_mm.c index 7998bc74ab49..f5c97a620962 100644 --- a/drivers/gpu/drm/i915/i915_mm.c +++ b/drivers/gpu/drm/i915/i915_mm.c @@ -122,13 +122,15 @@ int remap_io_mapping(struct vm_area_struct *vma, * @addr: target user address to start at * @size: size of map area * @sgl: Start sg entry + * @offset: offset from the start of the page * @iobase: Use stored dma address offset by this address or pfn if -1 * * Note: this is only safe if the mm semaphore is held when called. */ int remap_io_sg(struct vm_area_struct *vma, unsigned long addr, unsigned long size, - struct scatterlist *sgl, resource_size_t iobase) + struct scatterlist *sgl, unsigned long offset, + resource_size_t iobase) { struct remap_pfn r = { .mm = vma->vm_mm, @@ -141,6 +143,14 @@ int remap_io_sg(struct vm_area_struct *vma, /* We rely on prevalidation of the io-mapping to skip track_pfn(). */ GEM_BUG_ON((vma->vm_flags & EXPECTED_FLAGS) != EXPECTED_FLAGS); + while (offset >= sg_dma_len(r.sgt.sgp) >> PAGE_SHIFT) { + offset -= sg_dma_len(r.sgt.sgp) >> PAGE_SHIFT; + r.sgt = __sgt_iter(__sg_next(r.sgt.sgp), use_dma(iobase)); + if (!r.sgt.sgp) + return -EINVAL; + } + r.sgt.curr = offset << PAGE_SHIFT; + if (!use_dma(iobase)) flush_cache_range(vma, addr, size); diff --git a/drivers/gpu/drm/i915/i915_mm.h b/drivers/gpu/drm/i915/i915_mm.h index 04c8974d822b..69f9351b1a1c 100644 --- a/drivers/gpu/drm/i915/i915_mm.h +++ b/drivers/gpu/drm/i915/i915_mm.h @@ -30,6 +30,7 @@ int remap_io_mapping(struct vm_area_struct *vma, int remap_io_sg(struct vm_area_struct *vma, unsigned long addr, unsigned long size, - struct scatterlist *sgl, resource_size_t iobase); + struct scatterlist *sgl, unsigned long offset, + resource_size_t iobase); #endif /* __I915_MM_H__ */ |