dect
/
linux-2.6
Archived
13
0
Fork 0
Code Releases Activity

drm/i915: Copy the updated reloc->presumed_offset back to the user 

If the userspace driver is using a constant relocation array with a
static buffer, they will pass the same relocation array back to the
kernel. So we *do* need to update the presumed offset value in those
relocations to reflect the current object so that they remain correct
with future batchbuffers and we avoid the necessity of having to suspend
execution and perform redundant relocations.

Fixes the regression introduced by 12f889c for applications using
absolute addressing on trees of buffer (i.e. the current consumers of
libdrm_intel.so).

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=30996
Reported-by: Wang, Jinjin <jinjin.wang@intel.com>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
This commit is contained in:
Chris Wilson 2010-10-20 20:59:57 +01:00
parent 69dc4987cb
commit b5dc608c98
1 changed files with 13 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

13
drivers/gpu/drm/i915/i915_gem.c
View File

@ -3399,6 +3399,15 @@ i915_gem_execbuffer_relocate(struct drm_i915_gem_object *obj,
iowrite32(reloc.delta, reloc_entry);
io_mapping_unmap_atomic(reloc_page, KM_USER0);
}
/* and update the user's relocation entry */
reloc.presumed_offset = target_offset;
if (__copy_to_user_inatomic(&user_relocs[i].presumed_offset,
&reloc.presumed_offset,
sizeof(reloc.presumed_offset))) {
ret = -EFAULT;
break;
}
}
drm_gem_object_unreference(target_obj);
@ -3560,6 +3569,10 @@ validate_exec_list(struct drm_i915_gem_exec_object2 *exec,
if (!access_ok(VERIFY_READ, ptr, length))
return -EFAULT;
/* we may also need to update the presumed offsets */
if (!access_ok(VERIFY_WRITE, ptr, length))
return -EFAULT;
if (fault_in_pages_readable(ptr, length))
return -EFAULT;
}