Merge tag 'v3.3.7' into 3.3/master
[zen-stable.git] / drivers / usb / mon / mon_text.c
blobad408251d9557c2504bd35dcd53ae416344bf08d
1 /*
2 * The USB Monitor, inspired by Dave Harding's USBMon.
4 * This is a text format reader.
5 */
7 #include <linux/kernel.h>
8 #include <linux/list.h>
9 #include <linux/usb.h>
10 #include <linux/slab.h>
11 #include <linux/time.h>
12 #include <linux/export.h>
13 #include <linux/mutex.h>
14 #include <linux/debugfs.h>
15 #include <linux/scatterlist.h>
16 #include <asm/uaccess.h>
18 #include "usb_mon.h"
21 * No, we do not want arbitrarily long data strings.
22 * Use the binary interface if you want to capture bulk data!
24 #define DATA_MAX 32
27 * Defined by USB 2.0 clause 9.3, table 9.2.
29 #define SETUP_MAX 8
32 * This limit exists to prevent OOMs when the user process stops reading.
33 * If usbmon were available to unprivileged processes, it might be open
34 * to a local DoS. But we have to keep to root in order to prevent
35 * password sniffing from HID devices.
37 #define EVENT_MAX (4*PAGE_SIZE / sizeof(struct mon_event_text))
40 * Potentially unlimited number; we limit it for similar allocations.
41 * The usbfs limits this to 128, but we're not quite as generous.
43 #define ISODESC_MAX 5
45 #define PRINTF_DFL 250 /* with 5 ISOs segs */
47 struct mon_iso_desc {
48 int status;
49 unsigned int offset;
50 unsigned int length; /* Unsigned here, signed in URB. Historic. */
53 struct mon_event_text {
54 struct list_head e_link;
55 int type; /* submit, complete, etc. */
56 unsigned long id; /* From pointer, most of the time */
57 unsigned int tstamp;
58 int busnum;
59 char devnum;
60 char epnum;
61 char is_in;
62 char xfertype;
63 int length; /* Depends on type: xfer length or act length */
64 int status;
65 int interval;
66 int start_frame;
67 int error_count;
68 char setup_flag;
69 char data_flag;
70 int numdesc; /* Full number */
71 struct mon_iso_desc isodesc[ISODESC_MAX];
72 unsigned char setup[SETUP_MAX];
73 unsigned char data[DATA_MAX];
76 #define SLAB_NAME_SZ 30
77 struct mon_reader_text {
78 struct kmem_cache *e_slab;
79 int nevents;
80 struct list_head e_list;
81 struct mon_reader r; /* In C, parent class can be placed anywhere */
83 wait_queue_head_t wait;
84 int printf_size;
85 char *printf_buf;
86 struct mutex printf_lock;
88 char slab_name[SLAB_NAME_SZ];
91 static struct dentry *mon_dir; /* Usually /sys/kernel/debug/usbmon */
93 static void mon_text_ctor(void *);
95 struct mon_text_ptr {
96 int cnt, limit;
97 char *pbuf;
100 static struct mon_event_text *
101 mon_text_read_wait(struct mon_reader_text *rp, struct file *file);
102 static void mon_text_read_head_t(struct mon_reader_text *rp,
103 struct mon_text_ptr *p, const struct mon_event_text *ep);
104 static void mon_text_read_head_u(struct mon_reader_text *rp,
105 struct mon_text_ptr *p, const struct mon_event_text *ep);
106 static void mon_text_read_statset(struct mon_reader_text *rp,
107 struct mon_text_ptr *p, const struct mon_event_text *ep);
108 static void mon_text_read_intstat(struct mon_reader_text *rp,
109 struct mon_text_ptr *p, const struct mon_event_text *ep);
110 static void mon_text_read_isostat(struct mon_reader_text *rp,
111 struct mon_text_ptr *p, const struct mon_event_text *ep);
112 static void mon_text_read_isodesc(struct mon_reader_text *rp,
113 struct mon_text_ptr *p, const struct mon_event_text *ep);
114 static void mon_text_read_data(struct mon_reader_text *rp,
115 struct mon_text_ptr *p, const struct mon_event_text *ep);
118 * mon_text_submit
119 * mon_text_complete
121 * May be called from an interrupt.
123 * This is called with the whole mon_bus locked, so no additional lock.
126 static inline char mon_text_get_setup(struct mon_event_text *ep,
127 struct urb *urb, char ev_type, struct mon_bus *mbus)
130 if (ep->xfertype != USB_ENDPOINT_XFER_CONTROL || ev_type != 'S')
131 return '-';
133 if (urb->setup_packet == NULL)
134 return 'Z'; /* '0' would be not as pretty. */
136 memcpy(ep->setup, urb->setup_packet, SETUP_MAX);
137 return 0;
140 static inline char mon_text_get_data(struct mon_event_text *ep, struct urb *urb,
141 int len, char ev_type, struct mon_bus *mbus)
143 void *src;
145 if (len <= 0)
146 return 'L';
147 if (len >= DATA_MAX)
148 len = DATA_MAX;
150 if (ep->is_in) {
151 if (ev_type != 'C')
152 return '<';
153 } else {
154 if (ev_type != 'S')
155 return '>';
158 if (urb->num_sgs == 0) {
159 src = urb->transfer_buffer;
160 if (src == NULL)
161 return 'Z'; /* '0' would be not as pretty. */
162 } else {
163 struct scatterlist *sg = urb->sg;
165 if (PageHighMem(sg_page(sg)))
166 return 'D';
168 /* For the text interface we copy only the first sg buffer */
169 len = min_t(int, sg->length, len);
170 src = sg_virt(sg);
173 memcpy(ep->data, src, len);
174 return 0;
177 static inline unsigned int mon_get_timestamp(void)
179 struct timeval tval;
180 unsigned int stamp;
182 do_gettimeofday(&tval);
183 stamp = tval.tv_sec & 0xFFF; /* 2^32 = 4294967296. Limit to 4096s. */
184 stamp = stamp * 1000000 + tval.tv_usec;
185 return stamp;
188 static void mon_text_event(struct mon_reader_text *rp, struct urb *urb,
189 char ev_type, int status)
191 struct mon_event_text *ep;
192 unsigned int stamp;
193 struct usb_iso_packet_descriptor *fp;
194 struct mon_iso_desc *dp;
195 int i, ndesc;
197 stamp = mon_get_timestamp();
199 if (rp->nevents >= EVENT_MAX ||
200 (ep = kmem_cache_alloc(rp->e_slab, GFP_ATOMIC)) == NULL) {
201 rp->r.m_bus->cnt_text_lost++;
202 return;
205 ep->type = ev_type;
206 ep->id = (unsigned long) urb;
207 ep->busnum = urb->dev->bus->busnum;
208 ep->devnum = urb->dev->devnum;
209 ep->epnum = usb_endpoint_num(&urb->ep->desc);
210 ep->xfertype = usb_endpoint_type(&urb->ep->desc);
211 ep->is_in = usb_urb_dir_in(urb);
212 ep->tstamp = stamp;
213 ep->length = (ev_type == 'S') ?
214 urb->transfer_buffer_length : urb->actual_length;
215 /* Collecting status makes debugging sense for submits, too */
216 ep->status = status;
218 if (ep->xfertype == USB_ENDPOINT_XFER_INT) {
219 ep->interval = urb->interval;
220 } else if (ep->xfertype == USB_ENDPOINT_XFER_ISOC) {
221 ep->interval = urb->interval;
222 ep->start_frame = urb->start_frame;
223 ep->error_count = urb->error_count;
225 ep->numdesc = urb->number_of_packets;
226 if (ep->xfertype == USB_ENDPOINT_XFER_ISOC &&
227 urb->number_of_packets > 0) {
228 if ((ndesc = urb->number_of_packets) > ISODESC_MAX)
229 ndesc = ISODESC_MAX;
230 fp = urb->iso_frame_desc;
231 dp = ep->isodesc;
232 for (i = 0; i < ndesc; i++) {
233 dp->status = fp->status;
234 dp->offset = fp->offset;
235 dp->length = (ev_type == 'S') ?
236 fp->length : fp->actual_length;
237 fp++;
238 dp++;
240 /* Wasteful, but simple to understand: ISO 'C' is sparse. */
241 if (ev_type == 'C')
242 ep->length = urb->transfer_buffer_length;
245 ep->setup_flag = mon_text_get_setup(ep, urb, ev_type, rp->r.m_bus);
246 ep->data_flag = mon_text_get_data(ep, urb, ep->length, ev_type,
247 rp->r.m_bus);
249 rp->nevents++;
250 list_add_tail(&ep->e_link, &rp->e_list);
251 wake_up(&rp->wait);
254 static void mon_text_submit(void *data, struct urb *urb)
256 struct mon_reader_text *rp = data;
257 mon_text_event(rp, urb, 'S', -EINPROGRESS);
260 static void mon_text_complete(void *data, struct urb *urb, int status)
262 struct mon_reader_text *rp = data;
263 mon_text_event(rp, urb, 'C', status);
266 static void mon_text_error(void *data, struct urb *urb, int error)
268 struct mon_reader_text *rp = data;
269 struct mon_event_text *ep;
271 if (rp->nevents >= EVENT_MAX ||
272 (ep = kmem_cache_alloc(rp->e_slab, GFP_ATOMIC)) == NULL) {
273 rp->r.m_bus->cnt_text_lost++;
274 return;
277 ep->type = 'E';
278 ep->id = (unsigned long) urb;
279 ep->busnum = urb->dev->bus->busnum;
280 ep->devnum = urb->dev->devnum;
281 ep->epnum = usb_endpoint_num(&urb->ep->desc);
282 ep->xfertype = usb_endpoint_type(&urb->ep->desc);
283 ep->is_in = usb_urb_dir_in(urb);
284 ep->tstamp = mon_get_timestamp();
285 ep->length = 0;
286 ep->status = error;
288 ep->setup_flag = '-';
289 ep->data_flag = 'E';
291 rp->nevents++;
292 list_add_tail(&ep->e_link, &rp->e_list);
293 wake_up(&rp->wait);
297 * Fetch next event from the circular buffer.
299 static struct mon_event_text *mon_text_fetch(struct mon_reader_text *rp,
300 struct mon_bus *mbus)
302 struct list_head *p;
303 unsigned long flags;
305 spin_lock_irqsave(&mbus->lock, flags);
306 if (list_empty(&rp->e_list)) {
307 spin_unlock_irqrestore(&mbus->lock, flags);
308 return NULL;
310 p = rp->e_list.next;
311 list_del(p);
312 --rp->nevents;
313 spin_unlock_irqrestore(&mbus->lock, flags);
314 return list_entry(p, struct mon_event_text, e_link);
319 static int mon_text_open(struct inode *inode, struct file *file)
321 struct mon_bus *mbus;
322 struct mon_reader_text *rp;
323 int rc;
325 mutex_lock(&mon_lock);
326 mbus = inode->i_private;
328 rp = kzalloc(sizeof(struct mon_reader_text), GFP_KERNEL);
329 if (rp == NULL) {
330 rc = -ENOMEM;
331 goto err_alloc;
333 INIT_LIST_HEAD(&rp->e_list);
334 init_waitqueue_head(&rp->wait);
335 mutex_init(&rp->printf_lock);
337 rp->printf_size = PRINTF_DFL;
338 rp->printf_buf = kmalloc(rp->printf_size, GFP_KERNEL);
339 if (rp->printf_buf == NULL) {
340 rc = -ENOMEM;
341 goto err_alloc_pr;
344 rp->r.m_bus = mbus;
345 rp->r.r_data = rp;
346 rp->r.rnf_submit = mon_text_submit;
347 rp->r.rnf_error = mon_text_error;
348 rp->r.rnf_complete = mon_text_complete;
350 snprintf(rp->slab_name, SLAB_NAME_SZ, "mon_text_%p", rp);
351 rp->e_slab = kmem_cache_create(rp->slab_name,
352 sizeof(struct mon_event_text), sizeof(long), 0,
353 mon_text_ctor);
354 if (rp->e_slab == NULL) {
355 rc = -ENOMEM;
356 goto err_slab;
359 mon_reader_add(mbus, &rp->r);
361 file->private_data = rp;
362 mutex_unlock(&mon_lock);
363 return 0;
365 // err_busy:
366 // kmem_cache_destroy(rp->e_slab);
367 err_slab:
368 kfree(rp->printf_buf);
369 err_alloc_pr:
370 kfree(rp);
371 err_alloc:
372 mutex_unlock(&mon_lock);
373 return rc;
377 * For simplicity, we read one record in one system call and throw out
378 * what does not fit. This means that the following does not work:
379 * dd if=/dbg/usbmon/0t bs=10
380 * Also, we do not allow seeks and do not bother advancing the offset.
382 static ssize_t mon_text_read_t(struct file *file, char __user *buf,
383 size_t nbytes, loff_t *ppos)
385 struct mon_reader_text *rp = file->private_data;
386 struct mon_event_text *ep;
387 struct mon_text_ptr ptr;
389 if (IS_ERR(ep = mon_text_read_wait(rp, file)))
390 return PTR_ERR(ep);
391 mutex_lock(&rp->printf_lock);
392 ptr.cnt = 0;
393 ptr.pbuf = rp->printf_buf;
394 ptr.limit = rp->printf_size;
396 mon_text_read_head_t(rp, &ptr, ep);
397 mon_text_read_statset(rp, &ptr, ep);
398 ptr.cnt += snprintf(ptr.pbuf + ptr.cnt, ptr.limit - ptr.cnt,
399 " %d", ep->length);
400 mon_text_read_data(rp, &ptr, ep);
402 if (copy_to_user(buf, rp->printf_buf, ptr.cnt))
403 ptr.cnt = -EFAULT;
404 mutex_unlock(&rp->printf_lock);
405 kmem_cache_free(rp->e_slab, ep);
406 return ptr.cnt;
409 static ssize_t mon_text_read_u(struct file *file, char __user *buf,
410 size_t nbytes, loff_t *ppos)
412 struct mon_reader_text *rp = file->private_data;
413 struct mon_event_text *ep;
414 struct mon_text_ptr ptr;
416 if (IS_ERR(ep = mon_text_read_wait(rp, file)))
417 return PTR_ERR(ep);
418 mutex_lock(&rp->printf_lock);
419 ptr.cnt = 0;
420 ptr.pbuf = rp->printf_buf;
421 ptr.limit = rp->printf_size;
423 mon_text_read_head_u(rp, &ptr, ep);
424 if (ep->type == 'E') {
425 mon_text_read_statset(rp, &ptr, ep);
426 } else if (ep->xfertype == USB_ENDPOINT_XFER_ISOC) {
427 mon_text_read_isostat(rp, &ptr, ep);
428 mon_text_read_isodesc(rp, &ptr, ep);
429 } else if (ep->xfertype == USB_ENDPOINT_XFER_INT) {
430 mon_text_read_intstat(rp, &ptr, ep);
431 } else {
432 mon_text_read_statset(rp, &ptr, ep);
434 ptr.cnt += snprintf(ptr.pbuf + ptr.cnt, ptr.limit - ptr.cnt,
435 " %d", ep->length);
436 mon_text_read_data(rp, &ptr, ep);
438 if (copy_to_user(buf, rp->printf_buf, ptr.cnt))
439 ptr.cnt = -EFAULT;
440 mutex_unlock(&rp->printf_lock);
441 kmem_cache_free(rp->e_slab, ep);
442 return ptr.cnt;
445 static struct mon_event_text *mon_text_read_wait(struct mon_reader_text *rp,
446 struct file *file)
448 struct mon_bus *mbus = rp->r.m_bus;
449 DECLARE_WAITQUEUE(waita, current);
450 struct mon_event_text *ep;
452 add_wait_queue(&rp->wait, &waita);
453 set_current_state(TASK_INTERRUPTIBLE);
454 while ((ep = mon_text_fetch(rp, mbus)) == NULL) {
455 if (file->f_flags & O_NONBLOCK) {
456 set_current_state(TASK_RUNNING);
457 remove_wait_queue(&rp->wait, &waita);
458 return ERR_PTR(-EWOULDBLOCK);
461 * We do not count nwaiters, because ->release is supposed
462 * to be called when all openers are gone only.
464 schedule();
465 if (signal_pending(current)) {
466 remove_wait_queue(&rp->wait, &waita);
467 return ERR_PTR(-EINTR);
469 set_current_state(TASK_INTERRUPTIBLE);
471 set_current_state(TASK_RUNNING);
472 remove_wait_queue(&rp->wait, &waita);
473 return ep;
476 static void mon_text_read_head_t(struct mon_reader_text *rp,
477 struct mon_text_ptr *p, const struct mon_event_text *ep)
479 char udir, utype;
481 udir = (ep->is_in ? 'i' : 'o');
482 switch (ep->xfertype) {
483 case USB_ENDPOINT_XFER_ISOC: utype = 'Z'; break;
484 case USB_ENDPOINT_XFER_INT: utype = 'I'; break;
485 case USB_ENDPOINT_XFER_CONTROL: utype = 'C'; break;
486 default: /* PIPE_BULK */ utype = 'B';
488 p->cnt += snprintf(p->pbuf + p->cnt, p->limit - p->cnt,
489 "%lx %u %c %c%c:%03u:%02u",
490 ep->id, ep->tstamp, ep->type,
491 utype, udir, ep->devnum, ep->epnum);
494 static void mon_text_read_head_u(struct mon_reader_text *rp,
495 struct mon_text_ptr *p, const struct mon_event_text *ep)
497 char udir, utype;
499 udir = (ep->is_in ? 'i' : 'o');
500 switch (ep->xfertype) {
501 case USB_ENDPOINT_XFER_ISOC: utype = 'Z'; break;
502 case USB_ENDPOINT_XFER_INT: utype = 'I'; break;
503 case USB_ENDPOINT_XFER_CONTROL: utype = 'C'; break;
504 default: /* PIPE_BULK */ utype = 'B';
506 p->cnt += snprintf(p->pbuf + p->cnt, p->limit - p->cnt,
507 "%lx %u %c %c%c:%d:%03u:%u",
508 ep->id, ep->tstamp, ep->type,
509 utype, udir, ep->busnum, ep->devnum, ep->epnum);
512 static void mon_text_read_statset(struct mon_reader_text *rp,
513 struct mon_text_ptr *p, const struct mon_event_text *ep)
516 if (ep->setup_flag == 0) { /* Setup packet is present and captured */
517 p->cnt += snprintf(p->pbuf + p->cnt, p->limit - p->cnt,
518 " s %02x %02x %04x %04x %04x",
519 ep->setup[0],
520 ep->setup[1],
521 (ep->setup[3] << 8) | ep->setup[2],
522 (ep->setup[5] << 8) | ep->setup[4],
523 (ep->setup[7] << 8) | ep->setup[6]);
524 } else if (ep->setup_flag != '-') { /* Unable to capture setup packet */
525 p->cnt += snprintf(p->pbuf + p->cnt, p->limit - p->cnt,
526 " %c __ __ ____ ____ ____", ep->setup_flag);
527 } else { /* No setup for this kind of URB */
528 p->cnt += snprintf(p->pbuf + p->cnt, p->limit - p->cnt,
529 " %d", ep->status);
533 static void mon_text_read_intstat(struct mon_reader_text *rp,
534 struct mon_text_ptr *p, const struct mon_event_text *ep)
536 p->cnt += snprintf(p->pbuf + p->cnt, p->limit - p->cnt,
537 " %d:%d", ep->status, ep->interval);
540 static void mon_text_read_isostat(struct mon_reader_text *rp,
541 struct mon_text_ptr *p, const struct mon_event_text *ep)
543 if (ep->type == 'S') {
544 p->cnt += snprintf(p->pbuf + p->cnt, p->limit - p->cnt,
545 " %d:%d:%d", ep->status, ep->interval, ep->start_frame);
546 } else {
547 p->cnt += snprintf(p->pbuf + p->cnt, p->limit - p->cnt,
548 " %d:%d:%d:%d",
549 ep->status, ep->interval, ep->start_frame, ep->error_count);
553 static void mon_text_read_isodesc(struct mon_reader_text *rp,
554 struct mon_text_ptr *p, const struct mon_event_text *ep)
556 int ndesc; /* Display this many */
557 int i;
558 const struct mon_iso_desc *dp;
560 p->cnt += snprintf(p->pbuf + p->cnt, p->limit - p->cnt,
561 " %d", ep->numdesc);
562 ndesc = ep->numdesc;
563 if (ndesc > ISODESC_MAX)
564 ndesc = ISODESC_MAX;
565 if (ndesc < 0)
566 ndesc = 0;
567 dp = ep->isodesc;
568 for (i = 0; i < ndesc; i++) {
569 p->cnt += snprintf(p->pbuf + p->cnt, p->limit - p->cnt,
570 " %d:%u:%u", dp->status, dp->offset, dp->length);
571 dp++;
575 static void mon_text_read_data(struct mon_reader_text *rp,
576 struct mon_text_ptr *p, const struct mon_event_text *ep)
578 int data_len, i;
580 if ((data_len = ep->length) > 0) {
581 if (ep->data_flag == 0) {
582 p->cnt += snprintf(p->pbuf + p->cnt, p->limit - p->cnt,
583 " =");
584 if (data_len >= DATA_MAX)
585 data_len = DATA_MAX;
586 for (i = 0; i < data_len; i++) {
587 if (i % 4 == 0) {
588 p->cnt += snprintf(p->pbuf + p->cnt,
589 p->limit - p->cnt,
590 " ");
592 p->cnt += snprintf(p->pbuf + p->cnt,
593 p->limit - p->cnt,
594 "%02x", ep->data[i]);
596 p->cnt += snprintf(p->pbuf + p->cnt, p->limit - p->cnt,
597 "\n");
598 } else {
599 p->cnt += snprintf(p->pbuf + p->cnt, p->limit - p->cnt,
600 " %c\n", ep->data_flag);
602 } else {
603 p->cnt += snprintf(p->pbuf + p->cnt, p->limit - p->cnt, "\n");
607 static int mon_text_release(struct inode *inode, struct file *file)
609 struct mon_reader_text *rp = file->private_data;
610 struct mon_bus *mbus;
611 /* unsigned long flags; */
612 struct list_head *p;
613 struct mon_event_text *ep;
615 mutex_lock(&mon_lock);
616 mbus = inode->i_private;
618 if (mbus->nreaders <= 0) {
619 printk(KERN_ERR TAG ": consistency error on close\n");
620 mutex_unlock(&mon_lock);
621 return 0;
623 mon_reader_del(mbus, &rp->r);
626 * In theory, e_list is protected by mbus->lock. However,
627 * after mon_reader_del has finished, the following is the case:
628 * - we are not on reader list anymore, so new events won't be added;
629 * - whole mbus may be dropped if it was orphaned.
630 * So, we better not touch mbus.
632 /* spin_lock_irqsave(&mbus->lock, flags); */
633 while (!list_empty(&rp->e_list)) {
634 p = rp->e_list.next;
635 ep = list_entry(p, struct mon_event_text, e_link);
636 list_del(p);
637 --rp->nevents;
638 kmem_cache_free(rp->e_slab, ep);
640 /* spin_unlock_irqrestore(&mbus->lock, flags); */
642 kmem_cache_destroy(rp->e_slab);
643 kfree(rp->printf_buf);
644 kfree(rp);
646 mutex_unlock(&mon_lock);
647 return 0;
650 static const struct file_operations mon_fops_text_t = {
651 .owner = THIS_MODULE,
652 .open = mon_text_open,
653 .llseek = no_llseek,
654 .read = mon_text_read_t,
655 .release = mon_text_release,
658 static const struct file_operations mon_fops_text_u = {
659 .owner = THIS_MODULE,
660 .open = mon_text_open,
661 .llseek = no_llseek,
662 .read = mon_text_read_u,
663 .release = mon_text_release,
666 int mon_text_add(struct mon_bus *mbus, const struct usb_bus *ubus)
668 struct dentry *d;
669 enum { NAMESZ = 10 };
670 char name[NAMESZ];
671 int busnum = ubus? ubus->busnum: 0;
672 int rc;
674 if (mon_dir == NULL)
675 return 0;
677 if (ubus != NULL) {
678 rc = snprintf(name, NAMESZ, "%dt", busnum);
679 if (rc <= 0 || rc >= NAMESZ)
680 goto err_print_t;
681 d = debugfs_create_file(name, 0600, mon_dir, mbus,
682 &mon_fops_text_t);
683 if (d == NULL)
684 goto err_create_t;
685 mbus->dent_t = d;
688 rc = snprintf(name, NAMESZ, "%du", busnum);
689 if (rc <= 0 || rc >= NAMESZ)
690 goto err_print_u;
691 d = debugfs_create_file(name, 0600, mon_dir, mbus, &mon_fops_text_u);
692 if (d == NULL)
693 goto err_create_u;
694 mbus->dent_u = d;
696 rc = snprintf(name, NAMESZ, "%ds", busnum);
697 if (rc <= 0 || rc >= NAMESZ)
698 goto err_print_s;
699 d = debugfs_create_file(name, 0600, mon_dir, mbus, &mon_fops_stat);
700 if (d == NULL)
701 goto err_create_s;
702 mbus->dent_s = d;
704 return 1;
706 err_create_s:
707 err_print_s:
708 debugfs_remove(mbus->dent_u);
709 mbus->dent_u = NULL;
710 err_create_u:
711 err_print_u:
712 if (ubus != NULL) {
713 debugfs_remove(mbus->dent_t);
714 mbus->dent_t = NULL;
716 err_create_t:
717 err_print_t:
718 return 0;
721 void mon_text_del(struct mon_bus *mbus)
723 debugfs_remove(mbus->dent_u);
724 if (mbus->dent_t != NULL)
725 debugfs_remove(mbus->dent_t);
726 debugfs_remove(mbus->dent_s);
730 * Slab interface: constructor.
732 static void mon_text_ctor(void *mem)
735 * Nothing to initialize. No, really!
736 * So, we fill it with garbage to emulate a reused object.
738 memset(mem, 0xe5, sizeof(struct mon_event_text));
741 int __init mon_text_init(void)
743 struct dentry *mondir;
745 mondir = debugfs_create_dir("usbmon", usb_debug_root);
746 if (IS_ERR(mondir)) {
747 /* debugfs not available, but we can use usbmon without it */
748 return 0;
750 if (mondir == NULL) {
751 printk(KERN_NOTICE TAG ": unable to create usbmon directory\n");
752 return -ENOMEM;
754 mon_dir = mondir;
755 return 0;
758 void mon_text_exit(void)
760 debugfs_remove(mon_dir);