From 6f23ee1fefdc1f80bd8a3ab04a1c41ab2dec14c9 Mon Sep 17 00:00:00 2001 From: Pete Zaitcev Date: Sat, 30 Dec 2006 22:43:10 -0800 Subject: USB: add binary API to usbmon This patch adds a new, "binary" API in addition to the old, text API usbmon had before. The new API allows for less CPU use, and it allows to capture all data from a packet where old API only captured 32 bytes at most. There are some limitations and conditions to this, e.g. in case someone constructs a URB with 1GB of data, it's not likely to be captured, because even the huge buffers of the new reader are finite. Nonetheless, I expect this new capability to capture all data for all real life scenarios. The downside is, a special user mode application is required where cat(1) worked before. I have sample code at http://people.redhat.com/zaitcev/linux/ and Paolo Abeni is working on patching libpcap. This patch was initially written by Paolo and later I tweaked it, and we had a little back-and-forth. So this is a jointly authored patch, but I am submitting this I am responsible for the bugs. Signed-off-by: Paolo Abeni Signed-off-by: Pete Zaitcev Signed-off-by: Greg Kroah-Hartman --- drivers/usb/mon/mon_main.c | 97 +++++++++++++++++++++++----------------------- 1 file changed, 48 insertions(+), 49 deletions(-) (limited to 'drivers/usb/mon/mon_main.c') diff --git a/drivers/usb/mon/mon_main.c b/drivers/usb/mon/mon_main.c index 394bbf2f68d..c9739e7b35e 100644 --- a/drivers/usb/mon/mon_main.c +++ b/drivers/usb/mon/mon_main.c @@ -9,7 +9,6 @@ #include #include #include -#include #include #include #include @@ -22,11 +21,10 @@ static void mon_complete(struct usb_bus *ubus, struct urb *urb); static void mon_stop(struct mon_bus *mbus); static void mon_dissolve(struct mon_bus *mbus, struct usb_bus *ubus); static void mon_bus_drop(struct kref *r); -static void mon_bus_init(struct dentry *mondir, struct usb_bus *ubus); +static void mon_bus_init(struct usb_bus *ubus); DEFINE_MUTEX(mon_lock); -static struct dentry *mon_dir; /* /dbg/usbmon */ static LIST_HEAD(mon_buses); /* All buses we know: struct mon_bus */ /* @@ -200,7 +198,7 @@ static void mon_stop(struct mon_bus *mbus) */ static void mon_bus_add(struct usb_bus *ubus) { - mon_bus_init(mon_dir, ubus); + mon_bus_init(ubus); } /* @@ -212,8 +210,8 @@ static void mon_bus_remove(struct usb_bus *ubus) mutex_lock(&mon_lock); list_del(&mbus->bus_link); - debugfs_remove(mbus->dent_t); - debugfs_remove(mbus->dent_s); + if (mbus->text_inited) + mon_text_del(mbus); mon_dissolve(mbus, ubus); kref_put(&mbus->ref, mon_bus_drop); @@ -281,13 +279,9 @@ static void mon_bus_drop(struct kref *r) * - refcount USB bus struct * - link */ -static void mon_bus_init(struct dentry *mondir, struct usb_bus *ubus) +static void mon_bus_init(struct usb_bus *ubus) { - struct dentry *d; struct mon_bus *mbus; - enum { NAMESZ = 10 }; - char name[NAMESZ]; - int rc; if ((mbus = kzalloc(sizeof(struct mon_bus), GFP_KERNEL)) == NULL) goto err_alloc; @@ -303,57 +297,54 @@ static void mon_bus_init(struct dentry *mondir, struct usb_bus *ubus) ubus->mon_bus = mbus; mbus->uses_dma = ubus->uses_dma; - rc = snprintf(name, NAMESZ, "%dt", ubus->busnum); - if (rc <= 0 || rc >= NAMESZ) - goto err_print_t; - d = debugfs_create_file(name, 0600, mondir, mbus, &mon_fops_text); - if (d == NULL) - goto err_create_t; - mbus->dent_t = d; - - rc = snprintf(name, NAMESZ, "%ds", ubus->busnum); - if (rc <= 0 || rc >= NAMESZ) - goto err_print_s; - d = debugfs_create_file(name, 0600, mondir, mbus, &mon_fops_stat); - if (d == NULL) - goto err_create_s; - mbus->dent_s = d; + mbus->text_inited = mon_text_add(mbus, ubus); + // mon_bin_add(...) mutex_lock(&mon_lock); list_add_tail(&mbus->bus_link, &mon_buses); mutex_unlock(&mon_lock); return; -err_create_s: -err_print_s: - debugfs_remove(mbus->dent_t); -err_create_t: -err_print_t: - kfree(mbus); err_alloc: return; } +/* + * Search a USB bus by number. Notice that USB bus numbers start from one, + * which we may later use to identify "all" with zero. + * + * This function must be called with mon_lock held. + * + * This is obviously inefficient and may be revised in the future. + */ +struct mon_bus *mon_bus_lookup(unsigned int num) +{ + struct list_head *p; + struct mon_bus *mbus; + + list_for_each (p, &mon_buses) { + mbus = list_entry(p, struct mon_bus, bus_link); + if (mbus->u_bus->busnum == num) { + return mbus; + } + } + return NULL; +} + static int __init mon_init(void) { struct usb_bus *ubus; - struct dentry *mondir; + int rc; - mondir = debugfs_create_dir("usbmon", NULL); - if (IS_ERR(mondir)) { - printk(KERN_NOTICE TAG ": debugfs is not available\n"); - return -ENODEV; - } - if (mondir == NULL) { - printk(KERN_NOTICE TAG ": unable to create usbmon directory\n"); - return -ENODEV; - } - mon_dir = mondir; + if ((rc = mon_text_init()) != 0) + goto err_text; + if ((rc = mon_bin_init()) != 0) + goto err_bin; if (usb_mon_register(&mon_ops_0) != 0) { printk(KERN_NOTICE TAG ": unable to register with the core\n"); - debugfs_remove(mondir); - return -ENODEV; + rc = -ENODEV; + goto err_reg; } // MOD_INC_USE_COUNT(which_module?); @@ -361,10 +352,17 @@ static int __init mon_init(void) mutex_lock(&usb_bus_list_lock); list_for_each_entry (ubus, &usb_bus_list, bus_list) { - mon_bus_init(mondir, ubus); + mon_bus_init(ubus); } mutex_unlock(&usb_bus_list_lock); return 0; + +err_reg: + mon_bin_exit(); +err_bin: + mon_text_exit(); +err_text: + return rc; } static void __exit mon_exit(void) @@ -381,8 +379,8 @@ static void __exit mon_exit(void) mbus = list_entry(p, struct mon_bus, bus_link); list_del(p); - debugfs_remove(mbus->dent_t); - debugfs_remove(mbus->dent_s); + if (mbus->text_inited) + mon_text_del(mbus); /* * This never happens, because the open/close paths in @@ -401,7 +399,8 @@ static void __exit mon_exit(void) } mutex_unlock(&mon_lock); - debugfs_remove(mon_dir); + mon_text_exit(); + mon_bin_exit(); } module_init(mon_init); -- cgit v1.2.3-70-g09d2