aboutsummaryrefslogtreecommitdiffstats
path: root/include/asm-generic/scatterlist.h
diff options
context:
space:
mode:
authorArnd Bergmann <arnd@arndb.de>2009-05-13 22:56:33 +0000
committerArnd Bergmann <arnd@klappe2.(none)>2009-06-11 21:02:37 +0200
commitaafe4dbed0bf6cbdb2e9f03e1d42f8a540d8541d (patch)
tree5cc3e500ebb234ad82928de0ed680373c616dc44 /include/asm-generic/scatterlist.h
parent9858c60cc2d33b18367b2bc6947e3ea23db26ccb (diff)
downloadkernel_samsung_smdk4412-aafe4dbed0bf6cbdb2e9f03e1d42f8a540d8541d.zip
kernel_samsung_smdk4412-aafe4dbed0bf6cbdb2e9f03e1d42f8a540d8541d.tar.gz
kernel_samsung_smdk4412-aafe4dbed0bf6cbdb2e9f03e1d42f8a540d8541d.tar.bz2
asm-generic: add generic versions of common headers
These are all kernel internal interfaces that get copied around a lot. In most cases, architectures can provide their own optimized versions, but these generic versions can work as well. I have tried to use the most common contents of each header to allow existing architectures to migrate easily. Thanks to Remis for suggesting a number of cleanups. Signed-off-by: Remis Lima Baima <remis.developer@googlemail.com> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Diffstat (limited to 'include/asm-generic/scatterlist.h')
-rw-r--r--include/asm-generic/scatterlist.h43
1 files changed, 43 insertions, 0 deletions
diff --git a/include/asm-generic/scatterlist.h b/include/asm-generic/scatterlist.h
new file mode 100644
index 0000000..8b94544
--- /dev/null
+++ b/include/asm-generic/scatterlist.h
@@ -0,0 +1,43 @@
+#ifndef __ASM_GENERIC_SCATTERLIST_H
+#define __ASM_GENERIC_SCATTERLIST_H
+
+#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;
+ dma_addr_t dma_address;
+ unsigned int dma_length;
+};
+
+/*
+ * These macros should be used after a dma_map_sg call has been done
+ * to get bus addresses of each of the SG entries and their lengths.
+ * You should only work with the number of sg entries pci_map_sg
+ * returns, or alternatively stop on the first sg_dma_len(sg) which
+ * is 0.
+ */
+#define sg_dma_address(sg) ((sg)->dma_address)
+#ifndef sg_dma_len
+/*
+ * Normally, you have an iommu on 64 bit machines, but not on 32 bit
+ * machines. Architectures that are differnt should override this.
+ */
+#if __BITS_PER_LONG == 64
+#define sg_dma_len(sg) ((sg)->dma_length)
+#else
+#define sg_dma_len(sg) ((sg)->length)
+#endif /* 64 bit */
+#endif /* sg_dma_len */
+
+#ifndef ISA_DMA_THRESHOLD
+#define ISA_DMA_THRESHOLD (~0UL)
+#endif
+
+#define ARCH_HAS_SG_CHAIN
+
+#endif /* __ASM_GENERIC_SCATTERLIST_H */