patch-2.4.21 linux-2.4.21/drivers/ieee1394/dma.h

• Lines: 85
• Date: 2003-06-13 07:51:34.000000000 -0700
• Orig file: linux-2.4.20/drivers/ieee1394/dma.h
• Orig date: 1969-12-31 16:00:00.000000000 -0800

diff -urN linux-2.4.20/drivers/ieee1394/dma.h linux-2.4.21/drivers/ieee1394/dma.h
@@ -0,0 +1,84 @@
+/*
+ * DMA region bookkeeping routines
+ *
+ * Copyright (C) 2002 Maas Digital LLC
+ *
+ * This code is licensed under the GPL.  See the file COPYING in the root
+ * directory of the kernel sources for details.
+ */
+
+#ifndef IEEE1394_DMA_H
+#define IEEE1394_DMA_H
+
+#include <linux/pci.h>
+#include <asm/scatterlist.h>
+
+/* struct dma_prog_region
+   
+   a small, physically-contiguous DMA buffer with random-access,
+   synchronous usage characteristics
+*/
+
+struct dma_prog_region {
+	unsigned char    *kvirt;     /* kernel virtual address */
+	struct pci_dev   *dev;       /* PCI device */
+	unsigned int      n_pages;   /* # of kernel pages */
+	dma_addr_t        bus_addr;  /* base bus address */
+};
+
+/* clear out all fields but do not allocate any memory */
+void dma_prog_region_init(struct dma_prog_region *prog);
+int  dma_prog_region_alloc(struct dma_prog_region *prog, unsigned long n_bytes, struct pci_dev *dev);
+void dma_prog_region_free(struct dma_prog_region *prog);
+
+static inline dma_addr_t dma_prog_region_offset_to_bus(struct dma_prog_region *prog, unsigned long offset)
+{
+	return prog->bus_addr + offset;
+}
+
+/* struct dma_region
+   
+   a large, non-physically-contiguous DMA buffer with streaming,
+   asynchronous usage characteristics
+*/
+
+struct dma_region {
+	unsigned char      *kvirt;       /* kernel virtual address */
+	struct pci_dev     *dev;         /* PCI device */
+	unsigned int        n_pages;     /* # of kernel pages */
+	unsigned int        n_dma_pages; /* # of IOMMU pages */
+	struct scatterlist *sglist;      /* IOMMU mapping */
+	int                 direction;   /* PCI_DMA_TODEVICE, etc */
+};
+
+/* clear out all fields but do not allocate anything */
+void dma_region_init(struct dma_region *dma);
+
+/* allocate the buffer and map it to the IOMMU */
+int  dma_region_alloc(struct dma_region *dma, unsigned long n_bytes, struct pci_dev *dev, int direction);
+
+/* unmap and free the buffer */
+void dma_region_free(struct dma_region *dma);
+
+/* sync the IO bus' view of the buffer with the CPU's view */
+void dma_region_sync(struct dma_region *dma, unsigned long offset, unsigned long len);
+
+/* map the buffer into a user space process */
+int  dma_region_mmap(struct dma_region *dma, struct file *file, struct vm_area_struct *vma);
+
+/* macro to index into a DMA region (or dma_prog_region) */
+#define dma_region_i(_dma, _type, _index) ( ((_type*) ((_dma)->kvirt)) + (_index) )
+
+/* return the DMA bus address of the byte with the given offset
+   relative to the beginning of the dma_region */
+dma_addr_t dma_region_offset_to_bus(struct dma_region *dma, unsigned long offset);
+
+/* round up a number of bytes to be a multiple of the PAGE_SIZE */
+static inline unsigned long round_up_to_page(unsigned long len)
+{
+	if(len % PAGE_SIZE)
+		len += PAGE_SIZE - (len % PAGE_SIZE);
+	return len;
+}
+
+#endif /* IEEE1394_DMA_H */