Mesa (master): gallium: Always map for READ flag when DISCARD is not set.

Brian Paul brianp at kemper.freedesktop.org
Tue Aug 18 23:56:54 UTC 2009


Module: Mesa
Branch: master
Commit: e3bc1fb6bcd3141df8ab9123c4f6c276f30f6649
URL:    http://cgit.freedesktop.org/mesa/mesa/commit/?id=e3bc1fb6bcd3141df8ab9123c4f6c276f30f6649

Author: José Fonseca <jfonseca at vmware.com>
Date:   Fri Aug 14 20:05:33 2009 +0100

gallium: Always map for READ flag when DISCARD is not set.

This prevents the driver from discarding a buffer when the whole buffer
is mapped for writing, but only a portion is effectively written.

This is a temporary fix, because WRITE shouldn't imply DISCARD.

The full fix implies using PIPE_BUFFER_USAGE_DISCARD, throughout
the code, and will go only into master.

---

 src/gallium/include/pipe/p_inlines.h |    7 +++++++
 1 files changed, 7 insertions(+), 0 deletions(-)

diff --git a/src/gallium/include/pipe/p_inlines.h b/src/gallium/include/pipe/p_inlines.h
index cf176c9..a5c1e82 100644
--- a/src/gallium/include/pipe/p_inlines.h
+++ b/src/gallium/include/pipe/p_inlines.h
@@ -63,6 +63,13 @@ pipe_buffer_map(struct pipe_screen *screen,
    if(screen->buffer_map_range) {
       unsigned offset = 0;
       unsigned length = buf->size;
+
+      /* XXX: Actually we should be using/detecting DISCARD
+       * instead of assuming that WRITE implies discard */
+      if((usage & PIPE_BUFFER_USAGE_CPU_WRITE) &&
+         !(usage & PIPE_BUFFER_USAGE_DISCARD))
+         usage |= PIPE_BUFFER_USAGE_CPU_READ;
+
       return screen->buffer_map_range(screen, buf, offset, length, usage);
    }
    else




More information about the mesa-commit mailing list