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drm/i915: Fix up address spaces in slow_kernel_write()

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Since we now get_user_pages() outside of the mutex prior to performing
the copy, we kmap() the page inside the copy routine and so need to
perform an ordinary memcpy() and not copy_from_user().

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Eric Anholt <eric@anholt.net>
This commit is contained in:
Chris Wilson 2010-05-27 14:15:35 +01:00 committed by Eric Anholt
parent 99a03df57c
commit ab34c22681
1 changed files with 17 additions and 25 deletions
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42
drivers/gpu/drm/i915/i915_gem.c
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@ -509,25 +509,24 @@ fast_user_write(struct io_mapping *mapping,
* page faults
*/
static inline int
static inline void
slow_kernel_write(struct io_mapping *mapping,
loff_t gtt_base, int gtt_offset,
struct page *user_page, int user_offset,
int length)
{
char *src_vaddr, *dst_vaddr;
unsigned long unwritten;
char __iomem *dst_vaddr;
char *src_vaddr;
dst_vaddr = io_mapping_map_atomic_wc(mapping, gtt_base);
src_vaddr = kmap_atomic(user_page, KM_USER1);
unwritten = __copy_from_user_inatomic_nocache(dst_vaddr + gtt_offset,
src_vaddr + user_offset,
length);
kunmap_atomic(src_vaddr, KM_USER1);
io_mapping_unmap_atomic(dst_vaddr);
if (unwritten)
return -EFAULT;
return 0;
dst_vaddr = io_mapping_map_wc(mapping, gtt_base);
src_vaddr = kmap(user_page);
memcpy_toio(dst_vaddr + gtt_offset,
src_vaddr + user_offset,
length);
kunmap(user_page);
io_mapping_unmap(dst_vaddr);
}
static inline int
@ -700,18 +699,11 @@ i915_gem_gtt_pwrite_slow(struct drm_device *dev, struct drm_gem_object *obj,
if ((data_page_offset + page_length) > PAGE_SIZE)
page_length = PAGE_SIZE - data_page_offset;
ret = slow_kernel_write(dev_priv->mm.gtt_mapping,
gtt_page_base, gtt_page_offset,
user_pages[data_page_index],
data_page_offset,
page_length);
/* If we get a fault while copying data, then (presumably) our
* source page isn't available. Return the error and we'll
* retry in the slow path.
*/
if (ret)
goto out_unpin_object;
slow_kernel_write(dev_priv->mm.gtt_mapping,
gtt_page_base, gtt_page_offset,
user_pages[data_page_index],
data_page_offset,
page_length);
remain -= page_length;
offset += page_length;