[109/121] drm/vmwgfx: Split GMR2_REMAP commands if they are to large

From: Ben Hutchings
Date: Sat Sep 07 2013 - 23:52:35 EST


3.2.51-rc1 review patch. If anyone has any objections, please let me know.

------------------

From: Jakob Bornecrantz <jakob@xxxxxxxxxx>

commit 6e4dcff3adbf25acb87e74500a58e3c07bdec40f upstream.

This fixes the piglit test texturing/max-texture-size
causing the VM to die due to a too large SVGA command.

Signed-off-by: Jakob Bornecrantz <jakob@xxxxxxxxxx>
Reviewed-by: Biran Paul <brianp@xxxxxxxxxx>
Reviewed-by: Zack Rusin <zackr@xxxxxxxxxx>
Signed-off-by: Dave Airlie <airlied@xxxxxxxxx>
Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
---
drivers/gpu/drm/vmwgfx/vmwgfx_gmr.c | 58 +++++++++++++++++++++++++------------
1 file changed, 39 insertions(+), 19 deletions(-)

--- a/drivers/gpu/drm/vmwgfx/vmwgfx_gmr.c
+++ b/drivers/gpu/drm/vmwgfx/vmwgfx_gmr.c
@@ -29,7 +29,9 @@
#include "drmP.h"
#include "ttm/ttm_bo_driver.h"

-#define VMW_PPN_SIZE sizeof(unsigned long)
+#define VMW_PPN_SIZE (sizeof(unsigned long))
+/* A future safe maximum remap size. */
+#define VMW_PPN_PER_REMAP ((31 * 1024) / VMW_PPN_SIZE)

static int vmw_gmr2_bind(struct vmw_private *dev_priv,
struct page *pages[],
@@ -38,43 +40,61 @@ static int vmw_gmr2_bind(struct vmw_priv
{
SVGAFifoCmdDefineGMR2 define_cmd;
SVGAFifoCmdRemapGMR2 remap_cmd;
- uint32_t define_size = sizeof(define_cmd) + 4;
- uint32_t remap_size = VMW_PPN_SIZE * num_pages + sizeof(remap_cmd) + 4;
uint32_t *cmd;
uint32_t *cmd_orig;
+ uint32_t define_size = sizeof(define_cmd) + sizeof(*cmd);
+ uint32_t remap_num = num_pages / VMW_PPN_PER_REMAP + ((num_pages % VMW_PPN_PER_REMAP) > 0);
+ uint32_t remap_size = VMW_PPN_SIZE * num_pages + (sizeof(remap_cmd) + sizeof(*cmd)) * remap_num;
+ uint32_t remap_pos = 0;
+ uint32_t cmd_size = define_size + remap_size;
uint32_t i;

- cmd_orig = cmd = vmw_fifo_reserve(dev_priv, define_size + remap_size);
+ cmd_orig = cmd = vmw_fifo_reserve(dev_priv, cmd_size);
if (unlikely(cmd == NULL))
return -ENOMEM;

define_cmd.gmrId = gmr_id;
define_cmd.numPages = num_pages;

+ *cmd++ = SVGA_CMD_DEFINE_GMR2;
+ memcpy(cmd, &define_cmd, sizeof(define_cmd));
+ cmd += sizeof(define_cmd) / sizeof(*cmd);
+
+ /*
+ * Need to split the command if there are too many
+ * pages that goes into the gmr.
+ */
+
remap_cmd.gmrId = gmr_id;
remap_cmd.flags = (VMW_PPN_SIZE > sizeof(*cmd)) ?
SVGA_REMAP_GMR2_PPN64 : SVGA_REMAP_GMR2_PPN32;
- remap_cmd.offsetPages = 0;
- remap_cmd.numPages = num_pages;

- *cmd++ = SVGA_CMD_DEFINE_GMR2;
- memcpy(cmd, &define_cmd, sizeof(define_cmd));
- cmd += sizeof(define_cmd) / sizeof(uint32);
+ while (num_pages > 0) {
+ unsigned long nr = min(num_pages, (unsigned long)VMW_PPN_PER_REMAP);
+
+ remap_cmd.offsetPages = remap_pos;
+ remap_cmd.numPages = nr;

- *cmd++ = SVGA_CMD_REMAP_GMR2;
- memcpy(cmd, &remap_cmd, sizeof(remap_cmd));
- cmd += sizeof(remap_cmd) / sizeof(uint32);
-
- for (i = 0; i < num_pages; ++i) {
- if (VMW_PPN_SIZE <= 4)
- *cmd = page_to_pfn(*pages++);
- else
- *((uint64_t *)cmd) = page_to_pfn(*pages++);
+ *cmd++ = SVGA_CMD_REMAP_GMR2;
+ memcpy(cmd, &remap_cmd, sizeof(remap_cmd));
+ cmd += sizeof(remap_cmd) / sizeof(*cmd);
+
+ for (i = 0; i < nr; ++i) {
+ if (VMW_PPN_SIZE <= 4)
+ *cmd = page_to_pfn(*pages++);
+ else
+ *((uint64_t *)cmd) = page_to_pfn(*pages++);

- cmd += VMW_PPN_SIZE / sizeof(*cmd);
+ cmd += VMW_PPN_SIZE / sizeof(*cmd);
+ }
+
+ num_pages -= nr;
+ remap_pos += nr;
}

- vmw_fifo_commit(dev_priv, define_size + remap_size);
+ BUG_ON(cmd != cmd_orig + cmd_size / sizeof(*cmd));
+
+ vmw_fifo_commit(dev_priv, cmd_size);

return 0;
}

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