blob: 0a1367b760a00947e72d1b539d3dc9f6e32cd3f5 [file] [log] [blame]
* The USB Monitor, inspired by Dave Harding's USBMon.
* mon_dma.c: Library which snoops on DMA areas.
* Copyright (C) 2005 Pete Zaitcev (
#include <linux/kernel.h>
#include <linux/list.h>
#include <linux/highmem.h>
#include <asm/page.h>
#include <linux/usb.h> /* Only needed for declarations in usb_mon.h */
#include "usb_mon.h"
#ifdef __i386__ /* CONFIG_ARCH_I386 does not exit */
#define MON_HAS_UNMAP 1
#define phys_to_page(phys) pfn_to_page((phys) >> PAGE_SHIFT)
char mon_dmapeek(unsigned char *dst, dma_addr_t dma_addr, int len)
struct page *pg;
unsigned long flags;
unsigned char *map;
unsigned char *ptr;
* On i386, a DMA handle is the "physical" address of a page.
* In other words, the bus address is equal to physical address.
* There is no IOMMU.
pg = phys_to_page(dma_addr);
* We are called from hardware IRQs in case of callbacks.
* But we can be called from softirq or process context in case
* of submissions. In such case, we need to protect KM_IRQ0.
map = kmap_atomic(pg, KM_IRQ0);
ptr = map + (dma_addr & (PAGE_SIZE-1));
memcpy(dst, ptr, len);
kunmap_atomic(map, KM_IRQ0);
return 0;
#endif /* __i386__ */
char mon_dmapeek(unsigned char *dst, dma_addr_t dma_addr, int len)
return 'D';