[ 3.5.y.z extended stable ] Patch "drm/vmwgfx: Split GMR2_REMAP commands if they are to large" has been added to staging queue

Luis Henriques luis.henriques at canonical.com
Thu Sep 5 10:51:13 UTC 2013


This is a note to let you know that I have just added a patch titled

    drm/vmwgfx: Split GMR2_REMAP commands if they are to large

to the linux-3.5.y-queue branch of the 3.5.y.z extended stable tree 
which can be found at:

 http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.5.y-queue

If you, or anyone else, feels it should not be added to this tree, please 
reply to this email.

For more information about the 3.5.y.z tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Luis

------

>From b6a44506a7fa32d85e543bb131707257d1bd8d97 Mon Sep 17 00:00:00 2001
From: Jakob Bornecrantz <jakob at vmware.com>
Date: Thu, 29 Aug 2013 02:32:53 +0200
Subject: [PATCH] drm/vmwgfx: Split GMR2_REMAP commands if they are to large

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 at vmware.com>
Reviewed-by: Biran Paul <brianp at vmware.com>
Reviewed-by: Zack Rusin <zackr at vmware.com>
Signed-off-by: Dave Airlie <airlied at gmail.com>
Signed-off-by: Luis Henriques <luis.henriques at canonical.com>
---
 drivers/gpu/drm/vmwgfx/vmwgfx_gmr.c | 58 +++++++++++++++++++++++++------------
 1 file changed, 39 insertions(+), 19 deletions(-)

diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_gmr.c b/drivers/gpu/drm/vmwgfx/vmwgfx_gmr.c
index 21ee782..e1978a2 100644
--- 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_private *dev_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);
+		*cmd++ = SVGA_CMD_REMAP_GMR2;
+		memcpy(cmd, &remap_cmd, sizeof(remap_cmd));
+		cmd += sizeof(remap_cmd) / sizeof(*cmd);

-	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++);
+		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;
 }
--
1.8.3.2





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