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-rw-r--r--drivers/usb/mon/Kconfig22
-rw-r--r--drivers/usb/mon/Makefile7
-rw-r--r--drivers/usb/mon/mon_main.c377
-rw-r--r--drivers/usb/mon/mon_stat.c74
-rw-r--r--drivers/usb/mon/mon_text.c405
-rw-r--r--drivers/usb/mon/usb_mon.h51
6 files changed, 936 insertions, 0 deletions
diff --git a/drivers/usb/mon/Kconfig b/drivers/usb/mon/Kconfig
new file mode 100644
index 000000000000..4e6152aa5f19
--- /dev/null
+++ b/drivers/usb/mon/Kconfig
@@ -0,0 +1,22 @@
+#
+# USB Monitor configuration
+#
+
+# In normal life, it makes little sense to have usbmon as a module, and in fact
+# it is harmful, because there is no way to autoload the module.
+# The 'm' option is allowed for hackers who debug the usbmon itself,
+# and for those who have usbcore as a module.
+config USB_MON
+ tristate "USB Monitor"
+ depends on USB
+ default y
+ help
+ If you say Y here, a component which captures the USB traffic
+ between peripheral-specific drivers and HC drivers will be built.
+ The USB_MON is similar in spirit and may be compatible with Dave
+ Harding's USBMon.
+
+ This is somewhat experimental at this time, but it should be safe,
+ as long as you aren't building this as a module and then removing it.
+
+ If unsure, say Y. Do not say M.
diff --git a/drivers/usb/mon/Makefile b/drivers/usb/mon/Makefile
new file mode 100644
index 000000000000..3cff8d444bb1
--- /dev/null
+++ b/drivers/usb/mon/Makefile
@@ -0,0 +1,7 @@
+#
+# Makefile for USB Core files and filesystem
+#
+
+usbmon-objs := mon_main.o mon_stat.o mon_text.o
+
+obj-$(CONFIG_USB_MON) += usbmon.o
diff --git a/drivers/usb/mon/mon_main.c b/drivers/usb/mon/mon_main.c
new file mode 100644
index 000000000000..aa9d00808e4e
--- /dev/null
+++ b/drivers/usb/mon/mon_main.c
@@ -0,0 +1,377 @@
+/*
+ * The USB Monitor, inspired by Dave Harding's USBMon.
+ *
+ * mon_main.c: Main file, module initiation and exit, registrations, etc.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/usb.h>
+#include <linux/debugfs.h>
+#include <linux/smp_lock.h>
+
+#include "usb_mon.h"
+#include "../core/hcd.h"
+
+static void mon_submit(struct usb_bus *ubus, struct urb *urb);
+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);
+
+DECLARE_MUTEX(mon_lock);
+
+static struct dentry *mon_dir; /* /dbg/usbmon */
+static LIST_HEAD(mon_buses); /* All buses we know: struct mon_bus */
+
+/*
+ * Link a reader into the bus.
+ *
+ * This must be called with mon_lock taken because of mbus->ref.
+ */
+void mon_reader_add(struct mon_bus *mbus, struct mon_reader *r)
+{
+ unsigned long flags;
+ struct usb_bus *ubus;
+
+ spin_lock_irqsave(&mbus->lock, flags);
+ if (mbus->nreaders == 0) {
+ ubus = mbus->u_bus;
+ if (ubus->monitored) {
+ /*
+ * Something is really broken, refuse to go on and
+ * possibly corrupt ops pointers or worse.
+ */
+ printk(KERN_ERR TAG ": bus %d is already monitored\n",
+ ubus->busnum);
+ spin_unlock_irqrestore(&mbus->lock, flags);
+ return;
+ }
+ ubus->monitored = 1;
+ }
+ mbus->nreaders++;
+ list_add_tail(&r->r_link, &mbus->r_list);
+ spin_unlock_irqrestore(&mbus->lock, flags);
+
+ kref_get(&mbus->ref);
+}
+
+/*
+ * Unlink reader from the bus.
+ *
+ * This is called with mon_lock taken, so we can decrement mbus->ref.
+ */
+void mon_reader_del(struct mon_bus *mbus, struct mon_reader *r)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&mbus->lock, flags);
+ list_del(&r->r_link);
+ --mbus->nreaders;
+ if (mbus->nreaders == 0)
+ mon_stop(mbus);
+ spin_unlock_irqrestore(&mbus->lock, flags);
+
+ kref_put(&mbus->ref, mon_bus_drop);
+}
+
+/*
+ */
+static void mon_submit(struct usb_bus *ubus, struct urb *urb)
+{
+ struct mon_bus *mbus;
+ unsigned long flags;
+ struct list_head *pos;
+ struct mon_reader *r;
+
+ mbus = ubus->mon_bus;
+ if (mbus == NULL)
+ goto out_unlocked;
+
+ spin_lock_irqsave(&mbus->lock, flags);
+ if (mbus->nreaders == 0)
+ goto out_locked;
+
+ list_for_each (pos, &mbus->r_list) {
+ r = list_entry(pos, struct mon_reader, r_link);
+ r->rnf_submit(r->r_data, urb);
+ }
+
+ spin_unlock_irqrestore(&mbus->lock, flags);
+ return;
+
+out_locked:
+ spin_unlock_irqrestore(&mbus->lock, flags);
+out_unlocked:
+ return;
+}
+
+/*
+ */
+static void mon_submit_error(struct usb_bus *ubus, struct urb *urb, int err)
+{
+ struct mon_bus *mbus;
+
+ mbus = ubus->mon_bus;
+ if (mbus == NULL)
+ goto out_unlocked;
+
+ /*
+ * XXX Capture the error code and the 'E' event.
+ */
+
+ return;
+
+out_unlocked:
+ return;
+}
+
+/*
+ */
+static void mon_complete(struct usb_bus *ubus, struct urb *urb)
+{
+ struct mon_bus *mbus;
+ unsigned long flags;
+ struct list_head *pos;
+ struct mon_reader *r;
+
+ mbus = ubus->mon_bus;
+ if (mbus == NULL) {
+ /*
+ * This should not happen.
+ * At this point we do not even know the bus number...
+ */
+ printk(KERN_ERR TAG ": Null mon bus in URB, pipe 0x%x\n",
+ urb->pipe);
+ return;
+ }
+
+ spin_lock_irqsave(&mbus->lock, flags);
+ list_for_each (pos, &mbus->r_list) {
+ r = list_entry(pos, struct mon_reader, r_link);
+ r->rnf_complete(r->r_data, urb);
+ }
+ spin_unlock_irqrestore(&mbus->lock, flags);
+}
+
+/* int (*unlink_urb) (struct urb *urb, int status); */
+
+/*
+ * Stop monitoring.
+ * Obviously this must be well locked, so no need to play with mb's.
+ */
+static void mon_stop(struct mon_bus *mbus)
+{
+ struct usb_bus *ubus = mbus->u_bus;
+
+ /*
+ * A stop can be called for a dissolved mon_bus in case of
+ * a reader staying across an rmmod foo_hcd.
+ */
+ if (ubus != NULL) {
+ ubus->monitored = 0;
+ mb();
+ }
+}
+
+/*
+ * Add a USB bus (usually by a modprobe foo-hcd)
+ *
+ * This does not return an error code because the core cannot care less
+ * if monitoring is not established.
+ */
+static void mon_bus_add(struct usb_bus *ubus)
+{
+ mon_bus_init(mon_dir, ubus);
+}
+
+/*
+ * Remove a USB bus (either from rmmod foo-hcd or from a hot-remove event).
+ */
+static void mon_bus_remove(struct usb_bus *ubus)
+{
+ struct mon_bus *mbus = ubus->mon_bus;
+
+ down(&mon_lock);
+ list_del(&mbus->bus_link);
+ debugfs_remove(mbus->dent_t);
+ debugfs_remove(mbus->dent_s);
+
+ mon_dissolve(mbus, ubus);
+ kref_put(&mbus->ref, mon_bus_drop);
+ up(&mon_lock);
+}
+
+/*
+ * Ops
+ */
+static struct usb_mon_operations mon_ops_0 = {
+ .urb_submit = mon_submit,
+ .urb_submit_error = mon_submit_error,
+ .urb_complete = mon_complete,
+ .bus_add = mon_bus_add,
+ .bus_remove = mon_bus_remove,
+};
+
+/*
+ * Tear usb_bus and mon_bus apart.
+ */
+static void mon_dissolve(struct mon_bus *mbus, struct usb_bus *ubus)
+{
+
+ /*
+ * Never happens, but...
+ */
+ if (ubus->monitored) {
+ printk(KERN_ERR TAG ": bus %d is dissolved while monitored\n",
+ ubus->busnum);
+ ubus->monitored = 0;
+ mb();
+ }
+
+ ubus->mon_bus = NULL;
+ mbus->u_bus = NULL;
+ mb();
+ // usb_bus_put(ubus);
+}
+
+/*
+ */
+static void mon_bus_drop(struct kref *r)
+{
+ struct mon_bus *mbus = container_of(r, struct mon_bus, ref);
+ kfree(mbus);
+}
+
+/*
+ * Initialize a bus for us:
+ * - allocate mon_bus
+ * - refcount USB bus struct
+ * - link
+ */
+static void mon_bus_init(struct dentry *mondir, struct usb_bus *ubus)
+{
+ struct dentry *d;
+ struct mon_bus *mbus;
+ enum { NAMESZ = 10 };
+ char name[NAMESZ];
+ int rc;
+
+ if ((mbus = kmalloc(sizeof(struct mon_bus), GFP_KERNEL)) == NULL)
+ goto err_alloc;
+ memset(mbus, 0, sizeof(struct mon_bus));
+ kref_init(&mbus->ref);
+ spin_lock_init(&mbus->lock);
+ INIT_LIST_HEAD(&mbus->r_list);
+
+ /*
+ * This usb_bus_get here is superfluous, because we receive
+ * a notification if usb_bus is about to be removed.
+ */
+ // usb_bus_get(ubus);
+ mbus->u_bus = ubus;
+ ubus->mon_bus = mbus;
+
+ 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;
+
+ down(&mon_lock);
+ list_add_tail(&mbus->bus_link, &mon_buses);
+ up(&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;
+}
+
+static int __init mon_init(void)
+{
+ struct usb_bus *ubus;
+ struct dentry *mondir;
+
+ mondir = debugfs_create_dir("usbmon", NULL);
+ if (IS_ERR(mondir)) {
+ printk(KERN_NOTICE TAG ": debugs 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 (usb_mon_register(&mon_ops_0) != 0) {
+ printk(KERN_NOTICE TAG ": unable to register with the core\n");
+ debugfs_remove(mondir);
+ return -ENODEV;
+ }
+ // MOD_INC_USE_COUNT(which_module?);
+
+ down(&usb_bus_list_lock);
+ list_for_each_entry (ubus, &usb_bus_list, bus_list) {
+ mon_bus_init(mondir, ubus);
+ }
+ up(&usb_bus_list_lock);
+ return 0;
+}
+
+static void __exit mon_exit(void)
+{
+ struct mon_bus *mbus;
+ struct list_head *p;
+
+ usb_mon_deregister();
+
+ down(&mon_lock);
+ while (!list_empty(&mon_buses)) {
+ p = mon_buses.next;
+ mbus = list_entry(p, struct mon_bus, bus_link);
+ list_del(p);
+
+ debugfs_remove(mbus->dent_t);
+ debugfs_remove(mbus->dent_s);
+
+ /*
+ * This never happens, because the open/close paths in
+ * file level maintain module use counters and so rmmod fails
+ * before reaching here. However, better be safe...
+ */
+ if (mbus->nreaders) {
+ printk(KERN_ERR TAG
+ ": Outstanding opens (%d) on usb%d, leaking...\n",
+ mbus->nreaders, mbus->u_bus->busnum);
+ atomic_set(&mbus->ref.refcount, 2); /* Force leak */
+ }
+
+ mon_dissolve(mbus, mbus->u_bus);
+ kref_put(&mbus->ref, mon_bus_drop);
+ }
+ up(&mon_lock);
+
+ debugfs_remove(mon_dir);
+}
+
+module_init(mon_init);
+module_exit(mon_exit);
+
+MODULE_LICENSE("GPL");
diff --git a/drivers/usb/mon/mon_stat.c b/drivers/usb/mon/mon_stat.c
new file mode 100644
index 000000000000..6e4b165d070a
--- /dev/null
+++ b/drivers/usb/mon/mon_stat.c
@@ -0,0 +1,74 @@
+/*
+ * The USB Monitor, inspired by Dave Harding's USBMon.
+ *
+ * This is the 's' or 'stat' reader which debugs usbmon itself.
+ * Note that this code blows through locks, so make sure that
+ * /dbg/usbmon/0s is well protected from non-root users.
+ *
+ */
+
+#include <linux/kernel.h>
+#include <linux/usb.h>
+#include <asm/uaccess.h>
+
+#include "usb_mon.h"
+
+#define STAT_BUF_SIZE 80
+
+struct snap {
+ int slen;
+ char str[STAT_BUF_SIZE];
+};
+
+static int mon_stat_open(struct inode *inode, struct file *file)
+{
+ struct mon_bus *mbus;
+ struct snap *sp;
+
+ if ((sp = kmalloc(sizeof(struct snap), GFP_KERNEL)) == NULL)
+ return -ENOMEM;
+
+ mbus = inode->u.generic_ip;
+
+ sp->slen = snprintf(sp->str, STAT_BUF_SIZE,
+ "nreaders %d text_lost %u\n",
+ mbus->nreaders, mbus->cnt_text_lost);
+
+ file->private_data = sp;
+ return 0;
+}
+
+static ssize_t mon_stat_read(struct file *file, char __user *buf,
+ size_t nbytes, loff_t *ppos)
+{
+ struct snap *sp = file->private_data;
+ loff_t pos = *ppos;
+ int cnt;
+
+ if (pos < 0 || pos >= sp->slen)
+ return 0;
+ if (nbytes == 0)
+ return 0;
+ if ((cnt = sp->slen - pos) > nbytes)
+ cnt = nbytes;
+ if (copy_to_user(buf, sp->str + pos, cnt))
+ return -EFAULT;
+ *ppos = pos + cnt;
+ return cnt;
+}
+
+static int mon_stat_release(struct inode *inode, struct file *file)
+{
+ return 0;
+}
+
+struct file_operations mon_fops_stat = {
+ .owner = THIS_MODULE,
+ .open = mon_stat_open,
+ .llseek = no_llseek,
+ .read = mon_stat_read,
+ /* .write = mon_stat_write, */
+ /* .poll = mon_stat_poll, */
+ /* .ioctl = mon_stat_ioctl, */
+ .release = mon_stat_release,
+};
diff --git a/drivers/usb/mon/mon_text.c b/drivers/usb/mon/mon_text.c
new file mode 100644
index 000000000000..755a4570477f
--- /dev/null
+++ b/drivers/usb/mon/mon_text.c
@@ -0,0 +1,405 @@
+/*
+ * The USB Monitor, inspired by Dave Harding's USBMon.
+ *
+ * This is a text format reader.
+ */
+
+#include <linux/kernel.h>
+#include <linux/list.h>
+#include <linux/usb.h>
+#include <linux/time.h>
+#include <asm/uaccess.h>
+
+#include "usb_mon.h"
+
+/*
+ * No, we do not want arbitrarily long data strings.
+ * Use the binary interface if you want to capture bulk data!
+ */
+#define DATA_MAX 32
+
+/*
+ * This limit exists to prevent OOMs when the user process stops reading.
+ */
+#define EVENT_MAX 25
+
+#define PRINTF_DFL 120
+
+struct mon_event_text {
+ struct list_head e_link;
+ int type; /* submit, complete, etc. */
+ unsigned int pipe; /* Pipe */
+ unsigned long id; /* From pointer, most of the time */
+ unsigned int tstamp;
+ int length; /* Depends on type: xfer length or act length */
+ int status;
+ char data_flag;
+ unsigned char data[DATA_MAX];
+};
+
+#define SLAB_NAME_SZ 30
+struct mon_reader_text {
+ kmem_cache_t *e_slab;
+ int nevents;
+ struct list_head e_list;
+ struct mon_reader r; /* In C, parent class can be placed anywhere */
+
+ wait_queue_head_t wait;
+ int printf_size;
+ char *printf_buf;
+ struct semaphore printf_lock;
+
+ char slab_name[SLAB_NAME_SZ];
+};
+
+static void mon_text_ctor(void *, kmem_cache_t *, unsigned long);
+static void mon_text_dtor(void *, kmem_cache_t *, unsigned long);
+
+/*
+ * mon_text_submit
+ * mon_text_complete
+ *
+ * May be called from an interrupt.
+ *
+ * This is called with the whole mon_bus locked, so no additional lock.
+ */
+
+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. */
+
+ /*
+ * Bulk is easy to shortcut reliably.
+ * XXX Control needs setup packet taken.
+ * XXX Other pipe types need consideration. Currently, we overdo it
+ * and collect garbage for them: better more than less.
+ */
+ if (usb_pipebulk(pipe) || usb_pipecontrol(pipe)) {
+ if (usb_pipein(pipe)) {
+ if (ev_type == 'S')
+ return '<';
+ } else {
+ if (ev_type == 'C')
+ return '>';
+ }
+ }
+
+ if (len >= DATA_MAX)
+ len = DATA_MAX;
+ memcpy(ep->data, urb->transfer_buffer, len);
+ return 0;
+}
+
+static inline unsigned int mon_get_timestamp(void)
+{
+ struct timeval tval;
+ unsigned int stamp;
+
+ do_gettimeofday(&tval);
+ stamp = tval.tv_sec & 0xFFFF; /* 2^32 = 4294967296. Limit to 4096s. */
+ stamp = stamp * 1000000 + tval.tv_usec;
+ return stamp;
+}
+
+static void mon_text_event(struct mon_reader_text *rp, struct urb *urb,
+ char ev_type)
+{
+ struct mon_event_text *ep;
+ unsigned int stamp;
+
+ stamp = mon_get_timestamp();
+
+ if (rp->nevents >= EVENT_MAX ||
+ (ep = kmem_cache_alloc(rp->e_slab, SLAB_ATOMIC)) == NULL) {
+ rp->r.m_bus->cnt_text_lost++;
+ return;
+ }
+
+ ep->type = ev_type;
+ ep->pipe = urb->pipe;
+ ep->id = (unsigned long) urb;
+ ep->tstamp = stamp;
+ ep->length = (ev_type == 'S') ?
+ urb->transfer_buffer_length : urb->actual_length;
+ /* Collecting status makes debugging sense for submits, too */
+ ep->status = urb->status;
+
+ ep->data_flag = mon_text_get_data(ep, urb, ep->length, ev_type);
+
+ rp->nevents++;
+ list_add_tail(&ep->e_link, &rp->e_list);
+ wake_up(&rp->wait);
+}
+
+static void mon_text_submit(void *data, struct urb *urb)
+{
+ struct mon_reader_text *rp = data;
+ mon_text_event(rp, urb, 'S');
+}
+
+static void mon_text_complete(void *data, struct urb *urb)
+{
+ struct mon_reader_text *rp = data;
+ mon_text_event(rp, urb, 'C');
+}
+
+/*
+ * Fetch next event from the circular buffer.
+ */
+static struct mon_event_text *mon_text_fetch(struct mon_reader_text *rp,
+ struct mon_bus *mbus)
+{
+ struct list_head *p;
+ unsigned long flags;
+
+ spin_lock_irqsave(&mbus->lock, flags);
+ if (list_empty(&rp->e_list)) {
+ spin_unlock_irqrestore(&mbus->lock, flags);
+ return NULL;
+ }
+ p = rp->e_list.next;
+ list_del(p);
+ --rp->nevents;
+ spin_unlock_irqrestore(&mbus->lock, flags);
+ return list_entry(p, struct mon_event_text, e_link);
+}
+
+/*
+ */
+static int mon_text_open(struct inode *inode, struct file *file)
+{
+ struct mon_bus *mbus;
+ struct usb_bus *ubus;
+ struct mon_reader_text *rp;
+ int rc;
+
+ down(&mon_lock);
+ mbus = inode->u.generic_ip;
+ ubus = mbus->u_bus;
+
+ rp = kmalloc(sizeof(struct mon_reader_text), GFP_KERNEL);
+ if (rp == NULL) {
+ rc = -ENOMEM;
+ goto err_alloc;
+ }
+ memset(rp, 0, sizeof(struct mon_reader_text));
+ INIT_LIST_HEAD(&rp->e_list);
+ init_waitqueue_head(&rp->wait);
+ init_MUTEX(&rp->printf_lock);
+
+ rp->printf_size = PRINTF_DFL;
+ rp->printf_buf = kmalloc(rp->printf_size, GFP_KERNEL);
+ if (rp->printf_buf == NULL) {
+ rc = -ENOMEM;
+ goto err_alloc_pr;
+ }
+
+ rp->r.m_bus = mbus;
+ rp->r.r_data = rp;
+ rp->r.rnf_submit = mon_text_submit;
+ rp->r.rnf_complete = mon_text_complete;
+
+ snprintf(rp->slab_name, SLAB_NAME_SZ, "mon%dt_%lx", ubus->busnum,
+ (long)rp);
+ rp->e_slab = kmem_cache_create(rp->slab_name,
+ sizeof(struct mon_event_text), sizeof(long), 0,
+ mon_text_ctor, mon_text_dtor);
+ if (rp->e_slab == NULL) {
+ rc = -ENOMEM;
+ goto err_slab;
+ }
+
+ mon_reader_add(mbus, &rp->r);
+
+ file->private_data = rp;
+ up(&mon_lock);
+ return 0;
+
+// err_busy:
+// kmem_cache_destroy(rp->e_slab);
+err_slab:
+ kfree(rp->printf_buf);
+err_alloc_pr:
+ kfree(rp);
+err_alloc:
+ up(&mon_lock);
+ return rc;
+}
+
+/*
+ * For simplicity, we read one record in one system call and throw out
+ * what does not fit. This means that the following does not work:
+ * dd if=/dbg/usbmon/0t bs=10
+ * Also, we do not allow seeks and do not bother advancing the offset.
+ */
+static ssize_t mon_text_read(struct file *file, char __user *buf,
+ size_t nbytes, loff_t *ppos)
+{
+ struct mon_reader_text *rp = file->private_data;
+ struct mon_bus *mbus = rp->r.m_bus;
+ DECLARE_WAITQUEUE(waita, current);
+ struct mon_event_text *ep;
+ int cnt, limit;
+ char *pbuf;
+ char udir, utype;
+ int data_len, i;
+
+ add_wait_queue(&rp->wait, &waita);
+ set_current_state(TASK_INTERRUPTIBLE);
+ while ((ep = mon_text_fetch(rp, mbus)) == NULL) {
+ if (file->f_flags & O_NONBLOCK) {
+ set_current_state(TASK_RUNNING);
+ remove_wait_queue(&rp->wait, &waita);
+ return -EWOULDBLOCK; /* Same as EAGAIN in Linux */
+ }
+ /*
+ * We do not count nwaiters, because ->release is supposed
+ * to be called when all openers are gone only.
+ */
+ schedule();
+ if (signal_pending(current)) {
+ remove_wait_queue(&rp->wait, &waita);
+ return -EINTR;
+ }
+ set_current_state(TASK_INTERRUPTIBLE);
+ }
+ set_current_state(TASK_RUNNING);
+ remove_wait_queue(&rp->wait, &waita);
+
+ down(&rp->printf_lock);
+ cnt = 0;
+ pbuf = rp->printf_buf;
+ limit = rp->printf_size;
+
+ udir = usb_pipein(ep->pipe) ? 'i' : 'o';
+ switch (usb_pipetype(ep->pipe)) {
+ case PIPE_ISOCHRONOUS: utype = 'Z'; break;
+ case PIPE_INTERRUPT: utype = 'I'; break;
+ case PIPE_CONTROL: utype = 'C'; break;
+ default: /* PIPE_BULK */ utype = 'B';
+ }
+ cnt += snprintf(pbuf + cnt, limit - cnt,
+ "%lx %u %c %c%c:%03u:%02u %d %d",
+ ep->id, ep->tstamp, ep->type,
+ utype, udir, usb_pipedevice(ep->pipe), usb_pipeendpoint(ep->pipe),
+ ep->status, ep->length);
+
+ if ((data_len = ep->length) > 0) {
+ if (ep->data_flag == 0) {
+ cnt += snprintf(pbuf + cnt, limit - cnt, " =");
+ if (data_len >= DATA_MAX)
+ data_len = DATA_MAX;
+ for (i = 0; i < data_len; i++) {
+ if (i % 4 == 0) {
+ cnt += snprintf(pbuf + cnt, limit - cnt,
+ " ");
+ }
+ cnt += snprintf(pbuf + cnt, limit - cnt,
+ "%02x", ep->data[i]);
+ }
+ cnt += snprintf(pbuf + cnt, limit - cnt, "\n");
+ } else {
+ cnt += snprintf(pbuf + cnt, limit - cnt,
+ " %c\n", ep->data_flag);
+ }
+ } else {
+ cnt += snprintf(pbuf + cnt, limit - cnt, "\n");
+ }
+
+ if (copy_to_user(buf, rp->printf_buf, cnt))
+ cnt = -EFAULT;
+ up(&rp->printf_lock);
+ kmem_cache_free(rp->e_slab, ep);
+ return cnt;
+}
+
+static int mon_text_release(struct inode *inode, struct file *file)
+{
+ struct mon_reader_text *rp = file->private_data;
+ struct mon_bus *mbus;
+ /* unsigned long flags; */
+ struct list_head *p;
+ struct mon_event_text *ep;
+
+ down(&mon_lock);
+ mbus = inode->u.generic_ip;
+
+ if (mbus->nreaders <= 0) {
+ printk(KERN_ERR TAG ": consistency error on close\n");
+ up(&mon_lock);
+ return 0;
+ }
+ mon_reader_del(mbus, &rp->r);
+
+ /*
+ * In theory, e_list is protected by mbus->lock. However,
+ * after mon_reader_del has finished, the following is the case:
+ * - we are not on reader list anymore, so new events won't be added;
+ * - whole mbus may be dropped if it was orphaned.
+ * So, we better not touch mbus.
+ */
+ /* spin_lock_irqsave(&mbus->lock, flags); */
+ while (!list_empty(&rp->e_list)) {
+ p = rp->e_list.next;
+ ep = list_entry(p, struct mon_event_text, e_link);
+ list_del(p);
+ --rp->nevents;
+ kmem_cache_free(rp->e_slab, ep);
+ }
+ /* spin_unlock_irqrestore(&mbus->lock, flags); */
+
+ kmem_cache_destroy(rp->e_slab);
+ kfree(rp->printf_buf);
+ kfree(rp);
+
+ up(&mon_lock);
+ return 0;
+}
+
+struct file_operations mon_fops_text = {
+ .owner = THIS_MODULE,
+ .open = mon_text_open,
+ .llseek = no_llseek,
+ .read = mon_text_read,
+ /* .write = mon_text_write, */
+ /* .poll = mon_text_poll, */
+ /* .ioctl = mon_text_ioctl, */
+ .release = mon_text_release,
+};
+
+/*
+ * Slab interface: constructor.
+ */
+static void mon_text_ctor(void *mem, kmem_cache_t *slab, unsigned long sflags)
+{
+ /*
+ * Nothing to initialize. No, really!
+ * So, we fill it with garbage to emulate a reused object.
+ */
+ memset(mem, 0xe5, sizeof(struct mon_event_text));
+}
+
+static void mon_text_dtor(void *mem, kmem_cache_t *slab, unsigned long sflags)
+{
+ ;
+}
diff --git a/drivers/usb/mon/usb_mon.h b/drivers/usb/mon/usb_mon.h
new file mode 100644
index 000000000000..ed35c18a5c44
--- /dev/null
+++ b/drivers/usb/mon/usb_mon.h
@@ -0,0 +1,51 @@
+/*
+ * The USB Monitor, inspired by Dave Harding's USBMon.
+ */
+
+#ifndef __USB_MON_H
+#define __USB_MON_H
+
+#include <linux/list.h>
+#include <linux/slab.h>
+#include <linux/kref.h>
+/* #include <linux/usb.h> */ /* We use struct pointers only in this header */
+
+#define TAG "usbmon"
+
+struct mon_bus {
+ struct list_head bus_link;
+ spinlock_t lock;
+ struct dentry *dent_s; /* Debugging file */
+ struct dentry *dent_t; /* Text interface file */
+ struct usb_bus *u_bus;
+
+ /* Ref */
+ int nreaders; /* Under mon_lock AND mbus->lock */
+ struct list_head r_list; /* Chain of readers (usually one) */
+ struct kref ref; /* Under mon_lock */
+
+ /* Stats */
+ unsigned int cnt_text_lost;
+};
+
+/*
+ * An instance of a process which opened a file (but can fork later)
+ */
+struct mon_reader {
+ struct list_head r_link;
+ struct mon_bus *m_bus;
+ void *r_data; /* Use container_of instead? */
+
+ void (*rnf_submit)(void *data, struct urb *urb);
+ void (*rnf_complete)(void *data, struct urb *urb);
+};
+
+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 struct semaphore mon_lock;
+
+extern struct file_operations mon_fops_text;
+extern struct file_operations mon_fops_stat;
+
+#endif /* __USB_MON_H */
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-22 18:02:34 +0000