kernel/drivers/gpu/drm/vmwgfx/vmwgfx_blit.c, branch linux-4.17.yHosts the 0x221E linux distro kernel.https://universe.0xinfinity.dev/distro/kernel/atom?h=linux-4.17.y2018-03-22T11:08:23Zdrm/vmwgfx: Add a cpu blit utility that can be used for page-backed bos2018-03-22T11:08:23ZThomas Hellstromthellstrom@vmware.com2018-01-16T08:33:27Zurn:sha1:79273e1b7eb0e2007c5a9cae71af31075df8e6c5
The utility uses kmap_atomic() instead of vmapping the whole buffer
object. As a result there will be more book-keeping but on some
architectures this will help avoid exhausting vmalloc space and also
avoid expensive TLB flushes.
The blit utility also adds a provision to compute a bounding box of
changed content, which is very useful to optimize presentation speed
of ill-behaved applications that don't supply proper damage regions, and
for page-flips. The cost of computing the bounding box is not that
expensive when done in a cpu-blit utility like this.
Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Brian Paul <brianp@vmware.com>