diff options
author | Dmitry Torokhov <dtor_core@ameritech.net> | 2005-09-09 20:14:47 -0500 |
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committer | Dmitry Torokhov <dtor_core@ameritech.net> | 2005-09-09 20:14:47 -0500 |
commit | d344c5e0856ad03278d8700b503762dbc8b86e12 (patch) | |
tree | a6d893a643470a3c2580a58f3228a55fa1fd1d82 /drivers/usb/mon/mon_dma.c | |
parent | 010988e888a0abbe7118635c1b33d049caae6b29 (diff) | |
parent | 87fc767b832ef5a681a0ff9d203c3289bc3be2bf (diff) |
Manual merge with Linus
Diffstat (limited to 'drivers/usb/mon/mon_dma.c')
-rw-r--r-- | drivers/usb/mon/mon_dma.c | 55 |
1 files changed, 55 insertions, 0 deletions
diff --git a/drivers/usb/mon/mon_dma.c b/drivers/usb/mon/mon_dma.c new file mode 100644 index 000000000000..0a1367b760a0 --- /dev/null +++ b/drivers/usb/mon/mon_dma.c @@ -0,0 +1,55 @@ +/* + * The USB Monitor, inspired by Dave Harding's USBMon. + * + * mon_dma.c: Library which snoops on DMA areas. + * + * Copyright (C) 2005 Pete Zaitcev (zaitcev@redhat.com) + */ +#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. + */ + local_irq_save(flags); + map = kmap_atomic(pg, KM_IRQ0); + ptr = map + (dma_addr & (PAGE_SIZE-1)); + memcpy(dst, ptr, len); + kunmap_atomic(map, KM_IRQ0); + local_irq_restore(flags); + return 0; +} +#endif /* __i386__ */ + +#ifndef MON_HAS_UNMAP +char mon_dmapeek(unsigned char *dst, dma_addr_t dma_addr, int len) +{ + return 'D'; +} +#endif |