From 74b96e0de35261d1d110be02e6a121f2abd2a60e Mon Sep 17 00:00:00 2001
From: Alan Stern <stern@rowland.harvard.edu>
Date: Fri, 6 Nov 2009 12:32:23 -0500
Subject: [PATCH] --- yaml --- r: 174927 b: refs/heads/master c:
 b375e1169d8ecc9e9db3ecba8147d484b5510833 h: refs/heads/master i:   174925:
 7279e1f9dc64a795048b911cfd270ac822cfafab   174923:
 13151defd17bc3280119da9f710aa032dd9078d0   174919:
 c0f93c4477426980c87b5f52c96d5df9584be5fb   174911:
 e244c5936281bdb5f0426dea75649cb218405a05 v: v3

---
 [refs]                           |  2 +-
 trunk/drivers/usb/mon/mon_bin.c  | 51 ++++++++++++++++++++++++++------
 trunk/drivers/usb/mon/mon_text.c | 23 ++++++++++++--
 3 files changed, 63 insertions(+), 13 deletions(-)

diff --git a/[refs] b/[refs]
index 95169720cf19..e83968b313c7 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 40f8db8f8f5af2cafeb976ae15e11aca641a931d
+refs/heads/master: b375e1169d8ecc9e9db3ecba8147d484b5510833
diff --git a/trunk/drivers/usb/mon/mon_bin.c b/trunk/drivers/usb/mon/mon_bin.c
index 10f3205798e8..385ec0520167 100644
--- a/trunk/drivers/usb/mon/mon_bin.c
+++ b/trunk/drivers/usb/mon/mon_bin.c
@@ -16,6 +16,7 @@
 #include <linux/compat.h>
 #include <linux/mm.h>
 #include <linux/smp_lock.h>
+#include <linux/scatterlist.h>
 
 #include <asm/uaccess.h>
 
@@ -221,7 +222,7 @@ static void mon_free_buff(struct mon_pgmap *map, int npages);
 /*
  * This is a "chunked memcpy". It does not manipulate any counters.
  */
-static void mon_copy_to_buff(const struct mon_reader_bin *this,
+static unsigned int mon_copy_to_buff(const struct mon_reader_bin *this,
     unsigned int off, const unsigned char *from, unsigned int length)
 {
 	unsigned int step_len;
@@ -246,6 +247,7 @@ static void mon_copy_to_buff(const struct mon_reader_bin *this,
 		from += step_len;
 		length -= step_len;
 	}
+	return off;
 }
 
 /*
@@ -394,14 +396,44 @@ static inline char mon_bin_get_setup(unsigned char *setupb,
 	return 0;
 }
 
-static char mon_bin_get_data(const struct mon_reader_bin *rp,
-    unsigned int offset, struct urb *urb, unsigned int length)
+static unsigned int mon_bin_get_data(const struct mon_reader_bin *rp,
+    unsigned int offset, struct urb *urb, unsigned int length,
+    char *flag)
 {
+	int i;
+	struct scatterlist *sg;
+	unsigned int this_len;
+
+	*flag = 0;
+	if (urb->num_sgs == 0) {
+		if (urb->transfer_buffer == NULL) {
+			*flag = 'Z';
+			return length;
+		}
+		mon_copy_to_buff(rp, offset, urb->transfer_buffer, length);
+		length = 0;
 
-	if (urb->transfer_buffer == NULL)
-		return 'Z';
-	mon_copy_to_buff(rp, offset, urb->transfer_buffer, length);
-	return 0;
+	} else {
+		/* If IOMMU coalescing occurred, we cannot trust sg_page */
+		if (urb->sg->nents != urb->num_sgs) {
+			*flag = 'D';
+			return length;
+		}
+
+		/* Copy up to the first non-addressable segment */
+		for_each_sg(urb->sg->sg, sg, urb->num_sgs, i) {
+			if (length == 0 || PageHighMem(sg_page(sg)))
+				break;
+			this_len = min_t(unsigned int, sg->length, length);
+			offset = mon_copy_to_buff(rp, offset, sg_virt(sg),
+					this_len);
+			length -= this_len;
+		}
+		if (i == 0)
+			*flag = 'D';
+	}
+
+	return length;
 }
 
 static void mon_bin_get_isodesc(const struct mon_reader_bin *rp,
@@ -536,8 +568,9 @@ static void mon_bin_event(struct mon_reader_bin *rp, struct urb *urb,
 	}
 
 	if (length != 0) {
-		ep->flag_data = mon_bin_get_data(rp, offset, urb, length);
-		if (ep->flag_data != 0) {	/* Yes, it's 0x00, not '0' */
+		length = mon_bin_get_data(rp, offset, urb, length,
+				&ep->flag_data);
+		if (length > 0) {
 			delta = (ep->len_cap + PKT_ALIGN-1) & ~(PKT_ALIGN-1);
 			ep->len_cap -= length;
 			delta -= (ep->len_cap + PKT_ALIGN-1) & ~(PKT_ALIGN-1);
diff --git a/trunk/drivers/usb/mon/mon_text.c b/trunk/drivers/usb/mon/mon_text.c
index 9f1a9227ebe6..047568ff223d 100644
--- a/trunk/drivers/usb/mon/mon_text.c
+++ b/trunk/drivers/usb/mon/mon_text.c
@@ -10,6 +10,7 @@
 #include <linux/time.h>
 #include <linux/mutex.h>
 #include <linux/debugfs.h>
+#include <linux/scatterlist.h>
 #include <asm/uaccess.h>
 
 #include "usb_mon.h"
@@ -137,6 +138,8 @@ static inline char mon_text_get_setup(struct mon_event_text *ep,
 static inline char mon_text_get_data(struct mon_event_text *ep, struct urb *urb,
     int len, char ev_type, struct mon_bus *mbus)
 {
+	void *src;
+
 	if (len <= 0)
 		return 'L';
 	if (len >= DATA_MAX)
@@ -150,10 +153,24 @@ static inline char mon_text_get_data(struct mon_event_text *ep, struct urb *urb,
 			return '>';
 	}
 
-	if (urb->transfer_buffer == NULL)
-		return 'Z';	/* '0' would be not as pretty. */
+	if (urb->num_sgs == 0) {
+		src = urb->transfer_buffer;
+		if (src == NULL)
+			return 'Z';	/* '0' would be not as pretty. */
+	} else {
+		struct scatterlist *sg = urb->sg->sg;
+
+		/* If IOMMU coalescing occurred, we cannot trust sg_page */
+		if (urb->sg->nents != urb->num_sgs ||
+				PageHighMem(sg_page(sg)))
+			return 'D';
+
+		/* For the text interface we copy only the first sg buffer */
+		len = min_t(int, sg->length, len);
+		src = sg_virt(sg);
+	}
 
-	memcpy(ep->data, urb->transfer_buffer, len);
+	memcpy(ep->data, src, len);
 	return 0;
 }