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-rw-r--r--include/asm-frv/scatterlist.h32
1 files changed, 32 insertions, 0 deletions
diff --git a/include/asm-frv/scatterlist.h b/include/asm-frv/scatterlist.h
new file mode 100644
index 00000000000..fb38fd329a5
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+++ b/include/asm-frv/scatterlist.h
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+#ifndef _ASM_SCATTERLIST_H
+#define _ASM_SCATTERLIST_H
+
+/*
+ * Drivers must set either ->address or (preferred) ->page and ->offset
+ * to indicate where data must be transferred to/from.
+ *
+ * Using ->page is recommended since it handles highmem data as well as
+ * low mem. ->address is restricted to data which has a virtual mapping, and
+ * it will go away in the future. Updating to ->page can be automated very
+ * easily -- something like
+ *
+ * sg->address = some_ptr;
+ *
+ * can be rewritten as
+ *
+ * sg->page = virt_to_page(some_ptr);
+ * sg->offset = (unsigned long) some_ptr & ~PAGE_MASK;
+ *
+ * and that's it. There's no excuse for not highmem enabling YOUR driver. /jens
+ */
+struct scatterlist {
+ struct page *page; /* Location for highmem page, if any */
+ unsigned int offset; /* for highmem, page offset */
+
+ dma_addr_t dma_address;
+ unsigned int length;
+};
+
+#define ISA_DMA_THRESHOLD (0xffffffffUL)
+
+#endif /* !_ASM_SCATTERLIST_H */