4 files changed, 45 insertions, 11 deletions

diff --git a/drivers/usb/mon/Kconfig b/drivers/usb/mon/Kconfig
index 635745f57fb..5c6ffa2a612 100644
--- a/drivers/usb/mon/Kconfig
+++ b/drivers/usb/mon/Kconfig
@@ -4,7 +4,6 @@
 
 config USB_MON
 	tristate "USB Monitor"
-	depends on USB
 	help
 	  If you select this option, a component which captures the USB traffic
 	  between peripheral-specific drivers and HC drivers will be built.
diff --git a/drivers/usb/mon/mon_bin.c b/drivers/usb/mon/mon_bin.c
index 44cb37b5a4d..9a62e89d6dc 100644
--- a/drivers/usb/mon/mon_bin.c
+++ b/drivers/usb/mon/mon_bin.c
@@ -11,11 +11,11 @@
 #include <linux/types.h>
 #include <linux/fs.h>
 #include <linux/cdev.h>
+#include <linux/export.h>
 #include <linux/usb.h>
 #include <linux/poll.h>
 #include <linux/compat.h>
 #include <linux/mm.h>
-#include <linux/smp_lock.h>
 #include <linux/scatterlist.h>
 #include <linux/slab.h>
 
@@ -437,6 +437,28 @@ static unsigned int mon_bin_get_data(const struct mon_reader_bin *rp,
 	return length;
 }
 
+/*
+ * This is the look-ahead pass in case of 'C Zi', when actual_length cannot
+ * be used to determine the length of the whole contiguous buffer.
+ */
+static unsigned int mon_bin_collate_isodesc(const struct mon_reader_bin *rp,
+    struct urb *urb, unsigned int ndesc)
+{
+	struct usb_iso_packet_descriptor *fp;
+	unsigned int length;
+
+	length = 0;
+	fp = urb->iso_frame_desc;
+	while (ndesc-- != 0) {
+		if (fp->actual_length != 0) {
+			if (fp->offset + fp->actual_length > length)
+				length = fp->offset + fp->actual_length;
+		}
+		fp++;
+	}
+	return length;
+}
+
 static void mon_bin_get_isodesc(const struct mon_reader_bin *rp,
     unsigned int offset, struct urb *urb, char ev_type, unsigned int ndesc)
 {
@@ -479,6 +501,10 @@ static void mon_bin_event(struct mon_reader_bin *rp, struct urb *urb,
 	/*
 	 * Find the maximum allowable length, then allocate space.
 	 */
+	urb_length = (ev_type == 'S') ?
+	    urb->transfer_buffer_length : urb->actual_length;
+	length = urb_length;
+
 	if (usb_endpoint_xfer_isoc(epd)) {
 		if (urb->number_of_packets < 0) {
 			ndesc = 0;
@@ -487,14 +513,16 @@ static void mon_bin_event(struct mon_reader_bin *rp, struct urb *urb,
 		} else {
 			ndesc = urb->number_of_packets;
 		}
+		if (ev_type == 'C' && usb_urb_dir_in(urb))
+			length = mon_bin_collate_isodesc(rp, urb, ndesc);
 	} else {
 		ndesc = 0;
 	}
 	lendesc = ndesc*sizeof(struct mon_bin_isodesc);
 
-	urb_length = (ev_type == 'S') ?
-	    urb->transfer_buffer_length : urb->actual_length;
-	length = urb_length;
+	/* not an issue unless there's a subtle bug in a HCD somewhere */
+	if (length >= urb->transfer_buffer_length)
+		length = urb->transfer_buffer_length;
 
 	if (length >= rp->b_size/5)
 		length = rp->b_size/5;
@@ -1074,7 +1102,7 @@ static long mon_bin_ioctl(struct file *file, unsigned int cmd, unsigned long arg
 		nevents = mon_bin_queued(rp);
 
 		sp = (struct mon_bin_stats __user *)arg;
-		if (put_user(rp->cnt_lost, &sp->dropped))
+		if (put_user(ndropped, &sp->dropped))
 			return -EFAULT;
 		if (put_user(nevents, &sp->queued))
 			return -EFAULT;
@@ -1219,7 +1247,7 @@ static int mon_bin_mmap(struct file *filp, struct vm_area_struct *vma)
 {
 	/* don't do anything here: "fault" will set up page table entries */
 	vma->vm_ops = &mon_bin_vm_ops;
-	vma->vm_flags |= VM_RESERVED;
+	vma->vm_flags |= VM_DONTEXPAND | VM_DONTDUMP;
 	vma->vm_private_data = filp->private_data;
 	mon_bin_vma_open(vma);
 	return 0;
diff --git a/drivers/usb/mon/mon_stat.c b/drivers/usb/mon/mon_stat.c
index 8ec94f15a73..ebd6189a501 100644
--- a/drivers/usb/mon/mon_stat.c
+++ b/drivers/usb/mon/mon_stat.c
@@ -9,9 +9,9 @@
 
 #include <linux/kernel.h>
 #include <linux/slab.h>
+#include <linux/export.h>
 #include <linux/usb.h>
 #include <linux/fs.h>
-#include <linux/smp_lock.h>
 #include <asm/uaccess.h>
 
 #include "usb_mon.h"
diff --git a/drivers/usb/mon/mon_text.c b/drivers/usb/mon/mon_text.c
index a545d65f6e5..ad408251d95 100644
--- a/drivers/usb/mon/mon_text.c
+++ b/drivers/usb/mon/mon_text.c
@@ -9,6 +9,7 @@
 #include <linux/usb.h>
 #include <linux/slab.h>
 #include <linux/time.h>
+#include <linux/export.h>
 #include <linux/mutex.h>
 #include <linux/debugfs.h>
 #include <linux/scatterlist.h>
@@ -236,6 +237,9 @@ static void mon_text_event(struct mon_reader_text *rp, struct urb *urb,
 			fp++;
 			dp++;
 		}
+		/* Wasteful, but simple to understand: ISO 'C' is sparse. */
+		if (ev_type == 'C')
+			ep->length = urb->transfer_buffer_length;
 	}
 
 	ep->setup_flag = mon_text_get_setup(ep, urb, ev_type, rp->r.m_bus);
@@ -667,6 +671,9 @@ int mon_text_add(struct mon_bus *mbus, const struct usb_bus *ubus)
 	int busnum = ubus? ubus->busnum: 0;
 	int rc;
 
+	if (mon_dir == NULL)
+		return 0;
+
 	if (ubus != NULL) {
 		rc = snprintf(name, NAMESZ, "%dt", busnum);
 		if (rc <= 0 || rc >= NAMESZ)
@@ -737,12 +744,12 @@ int __init mon_text_init(void)
 
 	mondir = debugfs_create_dir("usbmon", usb_debug_root);
 	if (IS_ERR(mondir)) {
-		printk(KERN_NOTICE TAG ": debugfs is not available\n");
-		return -ENODEV;
+		/* debugfs not available, but we can use usbmon without it */
+		return 0;
 	}
 	if (mondir == NULL) {
 		printk(KERN_NOTICE TAG ": unable to create usbmon directory\n");
-		return -ENODEV;
+		return -ENOMEM;
 	}
 	mon_dir = mondir;
 	return 0;