[PATCH 5.4 074/135] drm/i915: Wean off drm_pci_alloc/drm_pci_free

From: Greg Kroah-Hartman
Date: Thu Feb 27 2020 - 09:09:50 EST


From: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx>

commit aa3146193ae25d0fe4b96d815169a135db2e8f01 upstream.

drm_pci_alloc and drm_pci_free are just very thin wrappers around
dma_alloc_coherent, with a note that we should be removing them.
Furthermore since

commit de09d31dd38a50fdce106c15abd68432eebbd014
Author: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx>
Date: Fri Jan 15 16:51:42 2016 -0800

page-flags: define PG_reserved behavior on compound pages

As far as I can see there's no users of PG_reserved on compound pages.
Let's use PF_NO_COMPOUND here.

drm_pci_alloc has been declared broken since it mixes GFP_COMP and
SetPageReserved. Avoid this conflict by weaning ourselves off using the
abstraction and using the dma functions directly.

Reported-by: Taketo Kabe
Closes: https://gitlab.freedesktop.org/drm/intel/issues/1027
Fixes: de09d31dd38a ("page-flags: define PG_reserved behavior on compound pages")
Signed-off-by: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx>
Cc: <stable@xxxxxxxxxxxxxxx> # v4.5+
Reviewed-by: Daniel Vetter <daniel.vetter@xxxxxxxx>
Link: https://patchwork.freedesktop.org/patch/msgid/20200202153934.3899472-1-chris@xxxxxxxxxxxxxxxxxx
(cherry picked from commit c6790dc22312f592c1434577258b31c48c72d52a)
Signed-off-by: Jani Nikula <jani.nikula@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
drivers/gpu/drm/i915/display/intel_display.c | 2
drivers/gpu/drm/i915/gem/i915_gem_object_types.h | 3
drivers/gpu/drm/i915/gem/i915_gem_phys.c | 98 +++++++++++------------
drivers/gpu/drm/i915/i915_gem.c | 8 -
4 files changed, 55 insertions(+), 56 deletions(-)

--- a/drivers/gpu/drm/i915/display/intel_display.c
+++ b/drivers/gpu/drm/i915/display/intel_display.c
@@ -10510,7 +10510,7 @@ static u32 intel_cursor_base(const struc
u32 base;

if (INTEL_INFO(dev_priv)->display.cursor_needs_physical)
- base = obj->phys_handle->busaddr;
+ base = sg_dma_address(obj->mm.pages->sgl);
else
base = intel_plane_ggtt_offset(plane_state);

--- a/drivers/gpu/drm/i915/gem/i915_gem_object_types.h
+++ b/drivers/gpu/drm/i915/gem/i915_gem_object_types.h
@@ -240,9 +240,6 @@ struct drm_i915_gem_object {

void *gvt_info;
};
-
- /** for phys allocated objects */
- struct drm_dma_handle *phys_handle;
};

static inline struct drm_i915_gem_object *
--- a/drivers/gpu/drm/i915/gem/i915_gem_phys.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_phys.c
@@ -21,88 +21,87 @@
static int i915_gem_object_get_pages_phys(struct drm_i915_gem_object *obj)
{
struct address_space *mapping = obj->base.filp->f_mapping;
- struct drm_dma_handle *phys;
- struct sg_table *st;
struct scatterlist *sg;
- char *vaddr;
+ struct sg_table *st;
+ dma_addr_t dma;
+ void *vaddr;
+ void *dst;
int i;
- int err;

if (WARN_ON(i915_gem_object_needs_bit17_swizzle(obj)))
return -EINVAL;

- /* Always aligning to the object size, allows a single allocation
+ /*
+ * Always aligning to the object size, allows a single allocation
* to handle all possible callers, and given typical object sizes,
* the alignment of the buddy allocation will naturally match.
*/
- phys = drm_pci_alloc(obj->base.dev,
- roundup_pow_of_two(obj->base.size),
- roundup_pow_of_two(obj->base.size));
- if (!phys)
+ vaddr = dma_alloc_coherent(&obj->base.dev->pdev->dev,
+ roundup_pow_of_two(obj->base.size),
+ &dma, GFP_KERNEL);
+ if (!vaddr)
return -ENOMEM;

- vaddr = phys->vaddr;
+ st = kmalloc(sizeof(*st), GFP_KERNEL);
+ if (!st)
+ goto err_pci;
+
+ if (sg_alloc_table(st, 1, GFP_KERNEL))
+ goto err_st;
+
+ sg = st->sgl;
+ sg->offset = 0;
+ sg->length = obj->base.size;
+
+ sg_assign_page(sg, (struct page *)vaddr);
+ sg_dma_address(sg) = dma;
+ sg_dma_len(sg) = obj->base.size;
+
+ dst = vaddr;
for (i = 0; i < obj->base.size / PAGE_SIZE; i++) {
struct page *page;
- char *src;
+ void *src;

page = shmem_read_mapping_page(mapping, i);
- if (IS_ERR(page)) {
- err = PTR_ERR(page);
- goto err_phys;
- }
+ if (IS_ERR(page))
+ goto err_st;

src = kmap_atomic(page);
- memcpy(vaddr, src, PAGE_SIZE);
- drm_clflush_virt_range(vaddr, PAGE_SIZE);
+ memcpy(dst, src, PAGE_SIZE);
+ drm_clflush_virt_range(dst, PAGE_SIZE);
kunmap_atomic(src);

put_page(page);
- vaddr += PAGE_SIZE;
+ dst += PAGE_SIZE;
}

intel_gt_chipset_flush(&to_i915(obj->base.dev)->gt);

- st = kmalloc(sizeof(*st), GFP_KERNEL);
- if (!st) {
- err = -ENOMEM;
- goto err_phys;
- }
-
- if (sg_alloc_table(st, 1, GFP_KERNEL)) {
- kfree(st);
- err = -ENOMEM;
- goto err_phys;
- }
-
- sg = st->sgl;
- sg->offset = 0;
- sg->length = obj->base.size;
-
- sg_dma_address(sg) = phys->busaddr;
- sg_dma_len(sg) = obj->base.size;
-
- obj->phys_handle = phys;
-
__i915_gem_object_set_pages(obj, st, sg->length);

return 0;

-err_phys:
- drm_pci_free(obj->base.dev, phys);
-
- return err;
+err_st:
+ kfree(st);
+err_pci:
+ dma_free_coherent(&obj->base.dev->pdev->dev,
+ roundup_pow_of_two(obj->base.size),
+ vaddr, dma);
+ return -ENOMEM;
}

static void
i915_gem_object_put_pages_phys(struct drm_i915_gem_object *obj,
struct sg_table *pages)
{
+ dma_addr_t dma = sg_dma_address(pages->sgl);
+ void *vaddr = sg_page(pages->sgl);
+
__i915_gem_object_release_shmem(obj, pages, false);

if (obj->mm.dirty) {
struct address_space *mapping = obj->base.filp->f_mapping;
- char *vaddr = obj->phys_handle->vaddr;
+ void *src = vaddr;
int i;

for (i = 0; i < obj->base.size / PAGE_SIZE; i++) {
@@ -114,15 +113,16 @@ i915_gem_object_put_pages_phys(struct dr
continue;

dst = kmap_atomic(page);
- drm_clflush_virt_range(vaddr, PAGE_SIZE);
- memcpy(dst, vaddr, PAGE_SIZE);
+ drm_clflush_virt_range(src, PAGE_SIZE);
+ memcpy(dst, src, PAGE_SIZE);
kunmap_atomic(dst);

set_page_dirty(page);
if (obj->mm.madv == I915_MADV_WILLNEED)
mark_page_accessed(page);
put_page(page);
- vaddr += PAGE_SIZE;
+
+ src += PAGE_SIZE;
}
obj->mm.dirty = false;
}
@@ -130,7 +130,9 @@ i915_gem_object_put_pages_phys(struct dr
sg_free_table(pages);
kfree(pages);

- drm_pci_free(obj->base.dev, obj->phys_handle);
+ dma_free_coherent(&obj->base.dev->pdev->dev,
+ roundup_pow_of_two(obj->base.size),
+ vaddr, dma);
}

static void phys_release(struct drm_i915_gem_object *obj)
--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -136,7 +136,7 @@ i915_gem_phys_pwrite(struct drm_i915_gem
struct drm_i915_gem_pwrite *args,
struct drm_file *file)
{
- void *vaddr = obj->phys_handle->vaddr + args->offset;
+ void *vaddr = sg_page(obj->mm.pages->sgl) + args->offset;
char __user *user_data = u64_to_user_ptr(args->data_ptr);

/*
@@ -802,10 +802,10 @@ i915_gem_pwrite_ioctl(struct drm_device
ret = i915_gem_gtt_pwrite_fast(obj, args);

if (ret == -EFAULT || ret == -ENOSPC) {
- if (obj->phys_handle)
- ret = i915_gem_phys_pwrite(obj, args, file);
- else
+ if (i915_gem_object_has_struct_page(obj))
ret = i915_gem_shmem_pwrite(obj, args);
+ else
+ ret = i915_gem_phys_pwrite(obj, args, file);
}

i915_gem_object_unpin_pages(obj);