intel/fake_bufmgr: Attempt to restrict references to objects in a batchbuffer > aperture size.

So with compiz on Intel hw with fake bufmgr, opening 4 firefox windows at 1680x1050 and hitting alt-tab, could cause the batchbuffer to try and reference more than the 32MB of RAM allocated.

Fix 1:
Fix 1 is to pre-verify the list of buffers against the current batchbuffer and if it can't possibly fit in the aperture to flush the batchbuffer to the hardware
and try again. If the buffers still can't fit well then you are hosed as I'm not sure there is a nice way to tell anyone.

Fix 2:
Next problem was that even with a simple check for total < aperture, we ran
into fragmentation issues, this meant that half way down a set of buffers,
we would fail as no blocks were available. Fix this by nuking the memory
manager from orbit and letting it start again and relayout the blocks in a
manner that fits.

Fix 3:
Finally the initial problem we were seeing was a memcpy to a NULL backing store.
We seem to end up with a texture at some point that never gets mapped but ends up with data in it. compiz al-tab icons have this property. So I created a card dirty bit that memcpy's any buffer that is !static and is written to back to memory. This probably is wrong but it makes compiz work for now.

Caveats:
965 support is still fail.

3 files changed, 31 insertions, 3 deletions

diff --git a/src/mesa/drivers/dri/intel/intel_batchbuffer.c b/src/mesa/drivers/dri/intel/intel_batchbuffer.c
index c1701f0640..d4abbb0860 100644
--- a/src/mesa/drivers/dri/intel/intel_batchbuffer.c
+++ b/src/mesa/drivers/dri/intel/intel_batchbuffer.c
@@ -87,6 +87,10 @@ intel_batchbuffer_reset(struct intel_batchbuffer *batch)
    batch->ptr = batch->map;
    batch->dirty_state = ~0;
    batch->cliprect_mode = IGNORE_CLIPRECTS;
+
+   /* account batchbuffer in aperture */
+   dri_bufmgr_check_aperture_space(batch->buf);
+
 }
 
 struct intel_batchbuffer *
@@ -264,7 +268,11 @@ intel_batchbuffer_emit_reloc(struct intel_batchbuffer *batch,
                              dri_bo *buffer,
                              GLuint flags, GLuint delta)
 {
-   dri_emit_reloc(batch->buf, flags, delta, batch->ptr - batch->map, buffer);
+   int ret;
+   int count = 0;
+
+   ret = dri_emit_reloc(batch->buf, flags, delta, batch->ptr - batch->map, buffer);
+
    /*
     * Using the old buffer offset, write in what the right data would be, in case
     * the buffer doesn't move and we can short-circuit the relocation processing
diff --git a/src/mesa/drivers/dri/intel/intel_blit.c b/src/mesa/drivers/dri/intel/intel_blit.c
index f4358bb3dd..0f990c00b4 100644
--- a/src/mesa/drivers/dri/intel/intel_blit.c
+++ b/src/mesa/drivers/dri/intel/intel_blit.c
@@ -54,6 +54,7 @@ intelCopyBuffer(const __DRIdrawablePrivate * dPriv,
 
    struct intel_context *intel;
    const intelScreenPrivate *intelScreen;
+   int ret;
 
    DBG("%s\n", __FUNCTION__);
 
@@ -123,6 +124,15 @@ intelCopyBuffer(const __DRIdrawablePrivate * dPriv,
       }
 #endif
 
+   again:
+      ret = dri_bufmgr_check_aperture_space(dst->buffer);
+      ret |= dri_bufmgr_check_aperture_space(src->buffer);
+      
+      if (ret) {
+	intel_batchbuffer_flush(intel->batch);
+	goto again;
+      }
+      
       for (i = 0; i < nbox; i++, pbox++) {
 	 drm_clip_rect_t box = *pbox;
 
diff --git a/src/mesa/drivers/dri/intel/intel_bufmgr_ttm.c b/src/mesa/drivers/dri/intel/intel_bufmgr_ttm.c
index f164b48963..6828425e77 100644
--- a/src/mesa/drivers/dri/intel/intel_bufmgr_ttm.c
+++ b/src/mesa/drivers/dri/intel/intel_bufmgr_ttm.c
@@ -817,7 +817,7 @@ dri_bufmgr_ttm_destroy(dri_bufmgr *bufmgr)
  * the relocation entry write when the buffer hasn't moved from the
  * last known offset in target_buf.
  */
-static void
+static int
 dri_ttm_emit_reloc(dri_bo *reloc_buf, uint64_t flags, GLuint delta,
 		   GLuint offset, dri_bo *target_buf)
 {
@@ -851,6 +851,7 @@ dri_ttm_emit_reloc(dri_bo *reloc_buf, uint64_t flags, GLuint delta,
     reloc_buf_ttm->reloc_buf_data[0]++; /* Increment relocation count */
     /* Check wraparound */
     assert(reloc_buf_ttm->reloc_buf_data[0] != 0);
+    return 0;
 }
 
 /**
@@ -1039,6 +1040,15 @@ intel_ttm_enable_bo_reuse(dri_bufmgr *bufmgr)
     }
 }
 
+/*
+ *
+ */
+static int
+dri_ttm_check_aperture_space(dri_bo *bo)
+{
+    return 0;
+}
+
 /**
  * Initializes the TTM buffer manager, which uses the kernel to allocate, map,
  * and manage map buffer objections.
@@ -1082,7 +1092,7 @@ intel_bufmgr_ttm_init(int fd, unsigned int fence_type,
     bufmgr_ttm->bufmgr.process_relocs = dri_ttm_process_reloc;
     bufmgr_ttm->bufmgr.post_submit = dri_ttm_post_submit;
     bufmgr_ttm->bufmgr.debug = GL_FALSE;
-
+    bufmgr_ttm->bufmgr.check_aperture_space = dri_ttm_check_aperture_space;
     /* Initialize the linked lists for BO reuse cache. */
     for (i = 0; i < INTEL_TTM_BO_BUCKETS; i++)
 	bufmgr_ttm->cache_bucket[i].tail = &bufmgr_ttm->cache_bucket[i].head;