rpms/kernel/devel kernel-2.6.spec, 1.1490, 1.1491 linux-2.6-usbmon-deficiency-workaround.patch, 1.1, 1.2

Thu Aug 18 05:35:52 UTC 2005

Author: davej

Update of /cvs/dist/rpms/kernel/devel
In directory cvs.devel.redhat.com:/tmp/cvs-serv6945

Modified Files:
	kernel-2.6.spec linux-2.6-usbmon-deficiency-workaround.patch 
Log Message:
Better workaround for the usbmon DMA deficiency.




Index: kernel-2.6.spec
===================================================================
RCS file: /cvs/dist/rpms/kernel/devel/kernel-2.6.spec,v
retrieving revision 1.1490
retrieving revision 1.1491
diff -u -r1.1490 -r1.1491

--- kernel-2.6.spec	18 Aug 2005 05:30:52 -0000	1.1490
+++ kernel-2.6.spec	18 Aug 2005 05:35:48 -0000	1.1491
@@ -1183,6 +1183,7 @@
 * Thu Aug 18 2005 Dave Jones <davej at redhat.com>
 - 2.6.13-rc6-git9
 - Fix up the 'last item on the boot cmdline gets eaten' bug.
+- Better workaround for the usbmon DMA deficiency.
 
 * Tue Aug 16 2005 Dave Jones <davej at redhat.com>
 - 2.6.13-rc6-git8

linux-2.6-usbmon-deficiency-workaround.patch:
 Makefile   |    2 +-
 mon_dma.c  |   55 +++++++++++++++++++++++++++++++++++++++++++++++++++++++
 mon_text.c |   35 +++++++++++++++++------------------
 usb_mon.h  |    4 ++++
 4 files changed, 77 insertions(+), 19 deletions(-)

Index: linux-2.6-usbmon-deficiency-workaround.patch
===================================================================
RCS file: /cvs/dist/rpms/kernel/devel/linux-2.6-usbmon-deficiency-workaround.patch,v
retrieving revision 1.1
retrieving revision 1.2
diff -u -r1.1 -r1.2
--- linux-2.6-usbmon-deficiency-workaround.patch	12 Jul 2005 21:24:39 -0000	1.1
+++ linux-2.6-usbmon-deficiency-workaround.patch	18 Aug 2005 05:35:48 -0000	1.2
@@ -1,38 +1,149 @@
 
-We have usbmon enabled now and it's good, but usb-storage moved away
-from under me a little bit. It now maps everything for DMA beforehand,
-which makes usbmon to miss the SCSI commands and replies.
-
-I am going to address this problem in usbmon, where it belongs, but
-it requires some work which is not done.
-
-What do you think about carrying the attached patch for a few months
-(I hope to turn around sooner, but you know how that works!)
+I came around with the usbmon fix (although it's for i386 only at this
+time - I would gladly take a patch for x86_64). So, would you please
+drop the workaround in usb-storage, patch 1402, and apply the attached
+instead?
 
 -- Pete
 
-diff -urp -X dontdiff linux-2.6.12/drivers/usb/storage/transport.c linux-2.6.12-lem/drivers/usb/storage/transport.c
---- linux-2.6.12/drivers/usb/storage/transport.c	2005-06-21 12:58:48.000000000 -0700
-+++ linux-2.6.12-lem/drivers/usb/storage/transport.c	2005-07-06 14:00:30.000000000 -0700
-@@ -948,8 +948,9 @@ int usb_stor_Bulk_max_lun(struct us_data
+diff -urpN -X dontdiff linux-2.6.13-rc6/drivers/usb/mon/Makefile linux-2.6.13-rc6-lem/drivers/usb/mon/Makefile
+--- linux-2.6.13-rc6/drivers/usb/mon/Makefile	2005-08-14 20:57:43.000000000 -0700
++++ linux-2.6.13-rc6-lem/drivers/usb/mon/Makefile	2005-08-15 11:25:32.000000000 -0700
+@@ -2,7 +2,7 @@
+ # Makefile for USB Core files and filesystem
+ #
  
- int usb_stor_Bulk_transport(struct scsi_cmnd *srb, struct us_data *us)
+-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
+diff -urpN -X dontdiff linux-2.6.13-rc6/drivers/usb/mon/mon_dma.c linux-2.6.13-rc6-lem/drivers/usb/mon/mon_dma.c
+--- linux-2.6.13-rc6/drivers/usb/mon/mon_dma.c	1969-12-31 16:00:00.000000000 -0800
++++ linux-2.6.13-rc6-lem/drivers/usb/mon/mon_dma.c	2005-08-15 16:11:51.000000000 -0700
+@@ -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 at 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
+diff -urpN -X dontdiff linux-2.6.13-rc6/drivers/usb/mon/mon_text.c linux-2.6.13-rc6-lem/drivers/usb/mon/mon_text.c
+--- linux-2.6.13-rc6/drivers/usb/mon/mon_text.c	2005-08-14 20:57:43.000000000 -0700
++++ linux-2.6.13-rc6-lem/drivers/usb/mon/mon_text.c	2005-08-15 11:44:13.000000000 -0700
+@@ -91,25 +91,11 @@ static inline char mon_text_get_data(str
+     int len, char ev_type)
  {
--	struct bulk_cb_wrap *bcb = (struct bulk_cb_wrap *) us->iobuf;
--	struct bulk_cs_wrap *bcs = (struct bulk_cs_wrap *) us->iobuf;
-+	/* Offset into iobuf a little in order to defeat pre-set DMA */
-+	struct bulk_cb_wrap *bcb = (struct bulk_cb_wrap *) (us->iobuf + 4);
-+	struct bulk_cs_wrap *bcs = (struct bulk_cs_wrap *) (us->iobuf + 4);
- 	unsigned int transfer_length = srb->request_bufflen;
- 	unsigned int residue;
- 	int result;
-@@ -960,7 +961,7 @@ int usb_stor_Bulk_transport(struct scsi_
- 	/* Take care of BULK32 devices; set extra byte to 0 */
- 	if ( unlikely(us->flags & US_FL_BULK32)) {
- 		cbwlen = 32;
--		us->iobuf[31] = 0;
-+		((unsigned char *)bcb)[31] = 0;
+ 	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. 
+@@ -126,8 +112,21 @@ static inline char mon_text_get_data(str
+ 		}
  	}
  
- 	/* set up the command wrapper */
+-	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;
+ }
+diff -urpN -X dontdiff linux-2.6.13-rc6/drivers/usb/mon/usb_mon.h linux-2.6.13-rc6-lem/drivers/usb/mon/usb_mon.h
+--- linux-2.6.13-rc6/drivers/usb/mon/usb_mon.h	2005-06-17 12:48:29.000000000 -0700
++++ linux-2.6.13-rc6-lem/drivers/usb/mon/usb_mon.h	2005-08-15 16:12:42.000000000 -0700
+@@ -43,6 +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;
 


