1 files changed, 38 insertions, 15 deletions

diff --git a/include/linux/scatterlist.h b/include/linux/scatterlist.h
index df7ddce..32326c2 100644
--- a/include/linux/scatterlist.h
+++ b/include/linux/scatterlist.h
@@ -1,6 +1,7 @@
 #ifndef _LINUX_SCATTERLIST_H
 #define _LINUX_SCATTERLIST_H
 
+#include <asm/types.h>
 #include <asm/scatterlist.h>
 #include <linux/mm.h>
 #include <linux/string.h>
@@ -26,18 +27,16 @@
 #define SG_MAGIC	0x87654321
 
 /**
- * sg_set_page - Set sg entry to point at given page
- * @sg:		 SG entry
- * @page:	 The page
+ * sg_assign_page - Assign a given page to an SG entry
+ * @sg:		    SG entry
+ * @page:	    The page
  *
  * Description:
- *   Use this function to set an sg entry pointing at a page, never assign
- *   the page directly. We encode sg table information in the lower bits
- *   of the page pointer. See sg_page() for looking up the page belonging
- *   to an sg entry.
+ *   Assign page to sg entry. Also see sg_set_page(), the most commonly used
+ *   variant.
  *
  **/
-static inline void sg_set_page(struct scatterlist *sg, struct page *page)
+static inline void sg_assign_page(struct scatterlist *sg, struct page *page)
 {
 	unsigned long page_link = sg->page_link & 0x3;
 
@@ -52,6 +51,28 @@ static inline void sg_set_page(struct scatterlist *sg, struct page *page)
 	sg->page_link = page_link | (unsigned long) page;
 }
 
+/**
+ * sg_set_page - Set sg entry to point at given page
+ * @sg:		 SG entry
+ * @page:	 The page
+ * @len:	 Length of data
+ * @offset:	 Offset into page
+ *
+ * Description:
+ *   Use this function to set an sg entry pointing at a page, never assign
+ *   the page directly. We encode sg table information in the lower bits
+ *   of the page pointer. See sg_page() for looking up the page belonging
+ *   to an sg entry.
+ *
+ **/
+static inline void sg_set_page(struct scatterlist *sg, struct page *page,
+			       unsigned int len, unsigned int offset)
+{
+	sg_assign_page(sg, page);
+	sg->offset = offset;
+	sg->length = len;
+}
+
 #define sg_page(sg)	((struct page *) ((sg)->page_link & ~0x3))
 
 /**
@@ -64,9 +85,7 @@ static inline void sg_set_page(struct scatterlist *sg, struct page *page)
 static inline void sg_set_buf(struct scatterlist *sg, const void *buf,
 			      unsigned int buflen)
 {
-	sg_set_page(sg, virt_to_page(buf));
-	sg->offset = offset_in_page(buf);
-	sg->length = buflen;
+	sg_set_page(sg, virt_to_page(buf), buflen, offset_in_page(buf));
 }
 
 /*
@@ -131,7 +150,7 @@ static inline struct scatterlist *sg_last(struct scatterlist *sgl,
 	struct scatterlist *ret = &sgl[nents - 1];
 #else
 	struct scatterlist *sg, *ret = NULL;
-	int i;
+	unsigned int i;
 
 	for_each_sg(sgl, sg, nents, i)
 		ret = sg;
@@ -160,7 +179,11 @@ static inline void sg_chain(struct scatterlist *prv, unsigned int prv_nents,
 #ifndef ARCH_HAS_SG_CHAIN
 	BUG();
 #endif
-	prv[prv_nents - 1].page_link = (unsigned long) sgl | 0x01;
+	/*
+	 * Set lowest bit to indicate a link pointer, and make sure to clear
+	 * the termination bit if it happens to be set.
+	 */
+	prv[prv_nents - 1].page_link = ((unsigned long) sgl | 0x01) & ~0x02;
 }
 
 /**
@@ -220,7 +243,7 @@ static inline void sg_init_table(struct scatterlist *sgl, unsigned int nents)
 	sg_mark_end(sgl, nents);
 #ifdef CONFIG_DEBUG_SG
 	{
-		int i;
+		unsigned int i;
 		for (i = 0; i < nents; i++)
 			sgl[i].sg_magic = SG_MAGIC;
 	}
@@ -237,7 +260,7 @@ static inline void sg_init_table(struct scatterlist *sgl, unsigned int nents)
  *   on the sg page.
  *
  **/
-static inline unsigned long sg_phys(struct scatterlist *sg)
+static inline dma_addr_t sg_phys(struct scatterlist *sg)
 {
 	return page_to_phys(sg_page(sg)) + sg->offset;
 }