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yaml
---
r: 7987
b: refs/heads/master
c: 0256839
h: refs/heads/master
i:
  7985: 1718352
  7983: 5683ca3
v: v3
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Pete Zaitcev authored and Greg Kroah-Hartman committed Sep 8, 2005
1 parent 023a032 commit 5eea2ca
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Showing 5 changed files with 78 additions and 20 deletions.
2 changes: 1 addition & 1 deletion [refs]
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@@ -1,2 +1,2 @@
---
refs/heads/master: d0384200f6b608e77fb5ddf7dfae1bf0e42c1c6e
refs/heads/master: 0256839619d9b1e933cafc83e7f0deaad4216465
2 changes: 1 addition & 1 deletion trunk/drivers/usb/mon/Makefile
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Expand Up @@ -2,7 +2,7 @@
# Makefile for USB Core files and filesystem
#

usbmon-objs := mon_main.o mon_stat.o mon_text.o
usbmon-objs := mon_main.o mon_stat.o mon_text.o mon_dma.o

# This does not use CONFIG_USB_MON because we want this to use a tristate.
obj-$(CONFIG_USB) += usbmon.o
55 changes: 55 additions & 0 deletions trunk/drivers/usb/mon/mon_dma.c
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@@ -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
35 changes: 17 additions & 18 deletions trunk/drivers/usb/mon/mon_text.c
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Expand Up @@ -91,25 +91,11 @@ static inline char mon_text_get_data(struct mon_event_text *ep, struct urb *urb,
int len, char ev_type)
{
int pipe = urb->pipe;
unsigned char *data;

/*
* The check to see if it's safe to poke at data has an enormous
* number of corner cases, but it seems that the following is
* more or less safe.
*
* We do not even try to look transfer_buffer, because it can
* contain non-NULL garbage in case the upper level promised to
* set DMA for the HCD.
*/
if (urb->transfer_flags & URB_NO_TRANSFER_DMA_MAP)
return 'D';

if (len <= 0)
return 'L';

if ((data = urb->transfer_buffer) == NULL)
return 'Z'; /* '0' would be not as pretty. */
if (len >= DATA_MAX)
len = DATA_MAX;

/*
* Bulk is easy to shortcut reliably.
Expand All @@ -126,8 +112,21 @@ static inline char mon_text_get_data(struct mon_event_text *ep, struct urb *urb,
}
}

if (len >= DATA_MAX)
len = DATA_MAX;
/*
* The check to see if it's safe to poke at data has an enormous
* number of corner cases, but it seems that the following is
* more or less safe.
*
* We do not even try to look transfer_buffer, because it can
* contain non-NULL garbage in case the upper level promised to
* set DMA for the HCD.
*/
if (urb->transfer_flags & URB_NO_TRANSFER_DMA_MAP)
return mon_dmapeek(ep->data, urb->transfer_dma, len);

if (urb->transfer_buffer == NULL)
return 'Z'; /* '0' would be not as pretty. */

memcpy(ep->data, urb->transfer_buffer, len);
return 0;
}
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4 changes: 4 additions & 0 deletions trunk/drivers/usb/mon/usb_mon.h
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Expand Up @@ -45,6 +45,10 @@ struct mon_reader {
void mon_reader_add(struct mon_bus *mbus, struct mon_reader *r);
void mon_reader_del(struct mon_bus *mbus, struct mon_reader *r);

/*
*/
extern char mon_dmapeek(unsigned char *dst, dma_addr_t dma_addr, int len);

extern struct semaphore mon_lock;

extern struct file_operations mon_fops_text;
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