Add CONFIG_DEBUG_SG sg validation
Add a Kconfig entry which will toggle some sanity checks on the sg
entry and tables.
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
diff --git a/include/asm-alpha/scatterlist.h b/include/asm-alpha/scatterlist.h
index b764706..440747c 100644
--- a/include/asm-alpha/scatterlist.h
+++ b/include/asm-alpha/scatterlist.h
@@ -5,6 +5,9 @@
#include <asm/types.h>
struct scatterlist {
+#ifdef CONFIG_DEBUG_SG
+ unsigned long sg_magic;
+#endif
unsigned long page_link;
unsigned int offset;
diff --git a/include/asm-arm/scatterlist.h b/include/asm-arm/scatterlist.h
index ab1d85d..ca0a37d 100644
--- a/include/asm-arm/scatterlist.h
+++ b/include/asm-arm/scatterlist.h
@@ -5,6 +5,9 @@
#include <asm/types.h>
struct scatterlist {
+#ifdef CONFIG_DEBUG_SG
+ unsigned long sg_magic;
+#endif
unsigned long page_link;
unsigned int offset; /* buffer offset */
dma_addr_t dma_address; /* dma address */
diff --git a/include/asm-avr32/scatterlist.h b/include/asm-avr32/scatterlist.h
index 1356f29..377320e 100644
--- a/include/asm-avr32/scatterlist.h
+++ b/include/asm-avr32/scatterlist.h
@@ -4,6 +4,9 @@
#include <asm/types.h>
struct scatterlist {
+#ifdef CONFIG_DEBUG_SG
+ unsigned long sg_magic;
+#endif
unsigned long page_link;
unsigned int offset;
dma_addr_t dma_address;
diff --git a/include/asm-blackfin/scatterlist.h b/include/asm-blackfin/scatterlist.h
index 384af54..32128d5 100644
--- a/include/asm-blackfin/scatterlist.h
+++ b/include/asm-blackfin/scatterlist.h
@@ -4,6 +4,9 @@
#include <linux/mm.h>
struct scatterlist {
+#ifdef CONFIG_DEBUG_SG
+ unsigned long sg_magic;
+#endif
unsigned long page_link;
unsigned int offset;
dma_addr_t dma_address;
diff --git a/include/asm-cris/scatterlist.h b/include/asm-cris/scatterlist.h
index 5a8a834..faff53a 100644
--- a/include/asm-cris/scatterlist.h
+++ b/include/asm-cris/scatterlist.h
@@ -2,6 +2,9 @@
#define __ASM_CRIS_SCATTERLIST_H
struct scatterlist {
+#ifdef CONFIG_DEBUG_SG
+ unsigned long sg_magic;
+#endif
char * address; /* Location data is to be transferred to */
unsigned int length;
diff --git a/include/asm-frv/scatterlist.h b/include/asm-frv/scatterlist.h
index 53dade7..f7da007 100644
--- a/include/asm-frv/scatterlist.h
+++ b/include/asm-frv/scatterlist.h
@@ -22,6 +22,9 @@
* and that's it. There's no excuse for not highmem enabling YOUR driver. /jens
*/
struct scatterlist {
+#ifdef CONFIG_DEBUG_SG
+ unsigned long sg_magic;
+#endif
unsigned long page_link;
unsigned int offset; /* for highmem, page offset */
diff --git a/include/asm-h8300/scatterlist.h b/include/asm-h8300/scatterlist.h
index 7e41983..d3ecdd8 100644
--- a/include/asm-h8300/scatterlist.h
+++ b/include/asm-h8300/scatterlist.h
@@ -4,6 +4,9 @@
#include <asm/types.h>
struct scatterlist {
+#ifdef CONFIG_DEBUG_SG
+ unsigned long sg_magic;
+#endif
unsigned long page_link;
unsigned int offset;
dma_addr_t dma_address;
diff --git a/include/asm-ia64/scatterlist.h b/include/asm-ia64/scatterlist.h
index 2f76ce3..d6f5787 100644
--- a/include/asm-ia64/scatterlist.h
+++ b/include/asm-ia64/scatterlist.h
@@ -9,6 +9,9 @@
#include <asm/types.h>
struct scatterlist {
+#ifdef CONFIG_DEBUG_SG
+ unsigned long sg_magic;
+#endif
unsigned long page_link;
unsigned int offset;
unsigned int length; /* buffer length */
diff --git a/include/asm-m32r/scatterlist.h b/include/asm-m32r/scatterlist.h
index 33b4b4d..1ed372c 100644
--- a/include/asm-m32r/scatterlist.h
+++ b/include/asm-m32r/scatterlist.h
@@ -4,6 +4,9 @@
#include <asm/types.h>
struct scatterlist {
+#ifdef CONFIG_DEBUG_SG
+ unsigned long sg_magic;
+#endif
char * address; /* Location data is to be transferred to, NULL for
* highmem page */
unsigned long page_link;
diff --git a/include/asm-m68k/scatterlist.h b/include/asm-m68k/scatterlist.h
index e06bb89..d3a7a0e 100644
--- a/include/asm-m68k/scatterlist.h
+++ b/include/asm-m68k/scatterlist.h
@@ -4,6 +4,9 @@
#include <linux/types.h>
struct scatterlist {
+#ifdef CONFIG_DEBUG_SG
+ unsigned long sg_magic;
+#endif
unsigned long page_link;
unsigned int offset;
unsigned int length;
diff --git a/include/asm-m68knommu/scatterlist.h b/include/asm-m68knommu/scatterlist.h
index 28bed41..1094284 100644
--- a/include/asm-m68knommu/scatterlist.h
+++ b/include/asm-m68knommu/scatterlist.h
@@ -5,6 +5,9 @@
#include <asm/types.h>
struct scatterlist {
+#ifdef CONFIG_DEBUG_SG
+ unsigned long sg_magic;
+#endif
unsigned long page_link;
unsigned int offset;
dma_addr_t dma_address;
diff --git a/include/asm-mips/scatterlist.h b/include/asm-mips/scatterlist.h
index 787797c..83d69fe 100644
--- a/include/asm-mips/scatterlist.h
+++ b/include/asm-mips/scatterlist.h
@@ -4,6 +4,9 @@
#include <asm/types.h>
struct scatterlist {
+#ifdef CONFIG_DEBUG_SG
+ unsigned long sg_magic;
+#endif
unsigned long page_link;
unsigned int offset;
dma_addr_t dma_address;
diff --git a/include/asm-parisc/scatterlist.h b/include/asm-parisc/scatterlist.h
index 26da914..cd3cfdf 100644
--- a/include/asm-parisc/scatterlist.h
+++ b/include/asm-parisc/scatterlist.h
@@ -5,6 +5,9 @@
#include <asm/types.h>
struct scatterlist {
+#ifdef CONFIG_DEBUG_SG
+ unsigned long sg_magic;
+#endif
unsigned long page_link;
unsigned int offset;
diff --git a/include/asm-powerpc/scatterlist.h b/include/asm-powerpc/scatterlist.h
index b9f1dbc..fcf7d55 100644
--- a/include/asm-powerpc/scatterlist.h
+++ b/include/asm-powerpc/scatterlist.h
@@ -14,6 +14,9 @@
#include <asm/dma.h>
struct scatterlist {
+#ifdef CONFIG_DEBUG_SG
+ unsigned long sg_magic;
+#endif
unsigned long page_link;
unsigned int offset;
unsigned int length;
diff --git a/include/asm-s390/scatterlist.h b/include/asm-s390/scatterlist.h
index eb39486..29ec8e2 100644
--- a/include/asm-s390/scatterlist.h
+++ b/include/asm-s390/scatterlist.h
@@ -2,6 +2,9 @@
#define _ASMS390_SCATTERLIST_H
struct scatterlist {
+#ifdef CONFIG_DEBUG_SG
+ unsigned long sg_magic;
+#endif
unsigned long page_link;
unsigned int offset;
unsigned int length;
diff --git a/include/asm-sh/scatterlist.h b/include/asm-sh/scatterlist.h
index bc7c809..a7d0d18 100644
--- a/include/asm-sh/scatterlist.h
+++ b/include/asm-sh/scatterlist.h
@@ -4,6 +4,9 @@
#include <asm/types.h>
struct scatterlist {
+#ifdef CONFIG_DEBUG_SG
+ unsigned long sg_magic;
+#endif
unsigned long page_link;
unsigned int offset;/* for highmem, page offset */
dma_addr_t dma_address;
diff --git a/include/asm-sh64/scatterlist.h b/include/asm-sh64/scatterlist.h
index 0afd856..5109251 100644
--- a/include/asm-sh64/scatterlist.h
+++ b/include/asm-sh64/scatterlist.h
@@ -14,6 +14,9 @@
#include <asm/types.h>
struct scatterlist {
+#ifdef CONFIG_DEBUG_SG
+ unsigned long sg_magic;
+#endif
unsigned long page_link;
unsigned int offset;/* for highmem, page offset */
dma_addr_t dma_address;
diff --git a/include/asm-sparc/scatterlist.h b/include/asm-sparc/scatterlist.h
index 45b16f1..e08d3d7 100644
--- a/include/asm-sparc/scatterlist.h
+++ b/include/asm-sparc/scatterlist.h
@@ -5,6 +5,9 @@
#include <linux/types.h>
struct scatterlist {
+#ifdef CONFIG_DEBUG_SG
+ unsigned long sg_magic;
+#endif
unsigned long page_link;
unsigned int offset;
diff --git a/include/asm-sparc64/scatterlist.h b/include/asm-sparc64/scatterlist.h
index 4cbaf7c..6df23f0 100644
--- a/include/asm-sparc64/scatterlist.h
+++ b/include/asm-sparc64/scatterlist.h
@@ -6,6 +6,9 @@
#include <asm/types.h>
struct scatterlist {
+#ifdef CONFIG_DEBUG_SG
+ unsigned long sg_magic;
+#endif
unsigned long page_link;
unsigned int offset;
diff --git a/include/asm-v850/scatterlist.h b/include/asm-v850/scatterlist.h
index db91feb..02d27b3 100644
--- a/include/asm-v850/scatterlist.h
+++ b/include/asm-v850/scatterlist.h
@@ -17,6 +17,9 @@
#include <asm/types.h>
struct scatterlist {
+#ifdef CONFIG_DEBUG_SG
+ unsigned long sg_magic;
+#endif
unsigned long page_link;
unsigned offset;
dma_addr_t dma_address;
diff --git a/include/asm-x86/scatterlist_32.h b/include/asm-x86/scatterlist_32.h
index 140a5b3..0e7d997 100644
--- a/include/asm-x86/scatterlist_32.h
+++ b/include/asm-x86/scatterlist_32.h
@@ -4,6 +4,9 @@
#include <asm/types.h>
struct scatterlist {
+#ifdef CONFIG_DEBUG_SG
+ unsigned long sg_magic;
+#endif
unsigned long page_link;
unsigned int offset;
dma_addr_t dma_address;
diff --git a/include/asm-x86/scatterlist_64.h b/include/asm-x86/scatterlist_64.h
index e344784..1847c72 100644
--- a/include/asm-x86/scatterlist_64.h
+++ b/include/asm-x86/scatterlist_64.h
@@ -4,6 +4,9 @@
#include <asm/types.h>
struct scatterlist {
+#ifdef CONFIG_DEBUG_SG
+ unsigned long sg_magic;
+#endif
unsigned long page_link;
unsigned int offset;
unsigned int length;
diff --git a/include/asm-xtensa/scatterlist.h b/include/asm-xtensa/scatterlist.h
index 3b8aba5..810080b 100644
--- a/include/asm-xtensa/scatterlist.h
+++ b/include/asm-xtensa/scatterlist.h
@@ -14,6 +14,9 @@
#include <asm/types.h>
struct scatterlist {
+#ifdef CONFIG_DEBUG_SG
+ unsigned long sg_magic;
+#endif
unsigned long page_link;
unsigned int offset;
dma_addr_t dma_address;
diff --git a/include/linux/scatterlist.h b/include/linux/scatterlist.h
index c6136e8..42daf5e 100644
--- a/include/linux/scatterlist.h
+++ b/include/linux/scatterlist.h
@@ -23,6 +23,8 @@
*
*/
+#define SG_MAGIC 0x87654321
+
/**
* sg_set_page - Set sg entry to point at given page
* @sg: SG entry
@@ -39,6 +41,9 @@
{
unsigned long page_link = sg->page_link & 0x3;
+#ifdef CONFIG_DEBUG_SG
+ BUG_ON(sg->sg_magic != SG_MAGIC);
+#endif
sg->page_link = page_link | (unsigned long) page;
}
@@ -81,6 +86,9 @@
**/
static inline struct scatterlist *sg_next(struct scatterlist *sg)
{
+#ifdef CONFIG_DEBUG_SG
+ BUG_ON(sg->sg_magic != SG_MAGIC);
+#endif
if (sg_is_last(sg))
return NULL;
@@ -124,6 +132,10 @@
ret = sg;
#endif
+#ifdef CONFIG_DEBUG_SG
+ BUG_ON(sgl[0].sg_magic != SG_MAGIC);
+ BUG_ON(!sg_is_last(ret));
+#endif
return ret;
}
@@ -180,6 +192,9 @@
unsigned int buflen)
{
memset(sg, 0, sizeof(*sg));
+#ifdef CONFIG_DEBUG_SG
+ sg->sg_magic = SG_MAGIC;
+#endif
sg_mark_end(sg, 1);
sg_set_buf(sg, buf, buflen);
}
@@ -198,6 +213,13 @@
{
memset(sgl, 0, sizeof(*sgl) * nents);
sg_mark_end(sgl, nents);
+#ifdef CONFIG_DEBUG_SG
+ {
+ int i;
+ for (i = 0; i < nents; i++)
+ sgl[i].sg_magic = SG_MAGIC;
+ }
+#endif
}
/**
diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index c567f21..1faa508 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -389,6 +389,16 @@
If unsure, say N.
+config DEBUG_SG
+ bool "Debug SG table operations"
+ depends on DEBUG_KERNEL
+ help
+ Enable this to turn on checks on scatter-gather tables. This can
+ help find problems with drivers that do not properly initialize
+ their sg tables.
+
+ If unsure, say N.
+
config FRAME_POINTER
bool "Compile the kernel with frame pointers"
depends on DEBUG_KERNEL && (X86 || CRIS || M68K || M68KNOMMU || FRV || UML || S390 || AVR32 || SUPERH || BFIN)