drm/i915: Move cmd parser pinning to execbuffer

We need to get rid of allocations in the cmd parser, because it needs
to be called from a signaling context, first move all pinning to
execbuf, where we already hold all locks.

Allocate jump_whitelist in the execbuffer, and add annotations around
intel_engine_cmd_parser(), to ensure we only call the command parser
without allocating any memory, or taking any locks we're not supposed to.

Because i915_gem_object_get_page() may also allocate memory, add a
path to i915_gem_object_get_sg() that prevents memory allocations,
and walk the sg list manually. It should be similarly fast.

This has the added benefit of being able to catch all memory allocation
errors before the point of no return, and return -ENOMEM safely to the
execbuf submitter.

Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Acked-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20210323155059.628690-4-maarten.lankhorst@linux.intel.com

drm/i915: Align start for memcpy_from_wc

The movntqda requires 16-byte alignment for the source pointer. Avoid
falling back to clflush if the source pointer is misaligned by doing the
doing a small uncached memcpy to fixup the alignments.

v2: Turn the unaligned copy into a genuine helper

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191211110437.4082687-5-chris@chris-wilson.co.uk

drm/i915: extract i915_memcpy.h from i915_drv.h

It used to be handy that we only had a couple of headers, but over time
i915_drv.h has become unwieldy. Extract declarations to a separate
header file corresponding to the implementation module, clarifying the
modularity of the driver.

Ensure the new header is self-contained, and do so with minimal further
includes, using forward declarations as needed. Include the new header
only where needed, and sort the modified include directives while at it
and as needed.

No functional changes.

Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/f2b887002150acdf218385ea846f7aa617aa5f15.1565271681.git.jani.nikula@intel.com