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1/*
2 * The USB Monitor, inspired by Dave Harding's USBMon.
3 *
4 * This is a binary format reader.
5 *
6 * Copyright (C) 2006 Paolo Abeni (paolo.abeni@email.it)
7 * Copyright (C) 2006,2007 Pete Zaitcev (zaitcev@redhat.com)
8 */
9
10#include <linux/kernel.h>
11#include <linux/types.h>
12#include <linux/fs.h>
13#include <linux/cdev.h>
14#include <linux/usb.h>
15#include <linux/poll.h>
16#include <linux/compat.h>
17#include <linux/mm.h>
18#include <linux/scatterlist.h>
19#include <linux/slab.h>
20
21#include <asm/uaccess.h>
22
23#include "usb_mon.h"
24
25/*
26 * Defined by USB 2.0 clause 9.3, table 9.2.
27 */
28#define SETUP_LEN 8
29
30/* ioctl macros */
31#define MON_IOC_MAGIC 0x92
32
33#define MON_IOCQ_URB_LEN _IO(MON_IOC_MAGIC, 1)
34/* #2 used to be MON_IOCX_URB, removed before it got into Linus tree */
35#define MON_IOCG_STATS _IOR(MON_IOC_MAGIC, 3, struct mon_bin_stats)
36#define MON_IOCT_RING_SIZE _IO(MON_IOC_MAGIC, 4)
37#define MON_IOCQ_RING_SIZE _IO(MON_IOC_MAGIC, 5)
38#define MON_IOCX_GET _IOW(MON_IOC_MAGIC, 6, struct mon_bin_get)
39#define MON_IOCX_MFETCH _IOWR(MON_IOC_MAGIC, 7, struct mon_bin_mfetch)
40#define MON_IOCH_MFLUSH _IO(MON_IOC_MAGIC, 8)
41/* #9 was MON_IOCT_SETAPI */
42#define MON_IOCX_GETX _IOW(MON_IOC_MAGIC, 10, struct mon_bin_get)
43
44#ifdef CONFIG_COMPAT
45#define MON_IOCX_GET32 _IOW(MON_IOC_MAGIC, 6, struct mon_bin_get32)
46#define MON_IOCX_MFETCH32 _IOWR(MON_IOC_MAGIC, 7, struct mon_bin_mfetch32)
47#define MON_IOCX_GETX32 _IOW(MON_IOC_MAGIC, 10, struct mon_bin_get32)
48#endif
49
50/*
51 * Some architectures have enormous basic pages (16KB for ia64, 64KB for ppc).
52 * But it's all right. Just use a simple way to make sure the chunk is never
53 * smaller than a page.
54 *
55 * N.B. An application does not know our chunk size.
56 *
57 * Woops, get_zeroed_page() returns a single page. I guess we're stuck with
58 * page-sized chunks for the time being.
59 */
60#define CHUNK_SIZE PAGE_SIZE
61#define CHUNK_ALIGN(x) (((x)+CHUNK_SIZE-1) & ~(CHUNK_SIZE-1))
62
63/*
64 * The magic limit was calculated so that it allows the monitoring
65 * application to pick data once in two ticks. This way, another application,
66 * which presumably drives the bus, gets to hog CPU, yet we collect our data.
67 * If HZ is 100, a 480 mbit/s bus drives 614 KB every jiffy. USB has an
68 * enormous overhead built into the bus protocol, so we need about 1000 KB.
69 *
70 * This is still too much for most cases, where we just snoop a few
71 * descriptor fetches for enumeration. So, the default is a "reasonable"
72 * amount for systems with HZ=250 and incomplete bus saturation.
73 *
74 * XXX What about multi-megabyte URBs which take minutes to transfer?
75 */
76#define BUFF_MAX CHUNK_ALIGN(1200*1024)
77#define BUFF_DFL CHUNK_ALIGN(300*1024)
78#define BUFF_MIN CHUNK_ALIGN(8*1024)
79
80/*
81 * The per-event API header (2 per URB).
82 *
83 * This structure is seen in userland as defined by the documentation.
84 */
85struct mon_bin_hdr {
86 u64 id; /* URB ID - from submission to callback */
87 unsigned char type; /* Same as in text API; extensible. */
88 unsigned char xfer_type; /* ISO, Intr, Control, Bulk */
89 unsigned char epnum; /* Endpoint number and transfer direction */
90 unsigned char devnum; /* Device address */
91 unsigned short busnum; /* Bus number */
92 char flag_setup;
93 char flag_data;
94 s64 ts_sec; /* gettimeofday */
95 s32 ts_usec; /* gettimeofday */
96 int status;
97 unsigned int len_urb; /* Length of data (submitted or actual) */
98 unsigned int len_cap; /* Delivered length */
99 union {
100 unsigned char setup[SETUP_LEN]; /* Only for Control S-type */
101 struct iso_rec {
102 int error_count;
103 int numdesc;
104 } iso;
105 } s;
106 int interval;
107 int start_frame;
108 unsigned int xfer_flags;
109 unsigned int ndesc; /* Actual number of ISO descriptors */
110};
111
112/*
113 * ISO vector, packed into the head of data stream.
114 * This has to take 16 bytes to make sure that the end of buffer
115 * wrap is not happening in the middle of a descriptor.
116 */
117struct mon_bin_isodesc {
118 int iso_status;
119 unsigned int iso_off;
120 unsigned int iso_len;
121 u32 _pad;
122};
123
124/* per file statistic */
125struct mon_bin_stats {
126 u32 queued;
127 u32 dropped;
128};
129
130struct mon_bin_get {
131 struct mon_bin_hdr __user *hdr; /* Can be 48 bytes or 64. */
132 void __user *data;
133 size_t alloc; /* Length of data (can be zero) */
134};
135
136struct mon_bin_mfetch {
137 u32 __user *offvec; /* Vector of events fetched */
138 u32 nfetch; /* Number of events to fetch (out: fetched) */
139 u32 nflush; /* Number of events to flush */
140};
141
142#ifdef CONFIG_COMPAT
143struct mon_bin_get32 {
144 u32 hdr32;
145 u32 data32;
146 u32 alloc32;
147};
148
149struct mon_bin_mfetch32 {
150 u32 offvec32;
151 u32 nfetch32;
152 u32 nflush32;
153};
154#endif
155
156/* Having these two values same prevents wrapping of the mon_bin_hdr */
157#define PKT_ALIGN 64
158#define PKT_SIZE 64
159
160#define PKT_SZ_API0 48 /* API 0 (2.6.20) size */
161#define PKT_SZ_API1 64 /* API 1 size: extra fields */
162
163#define ISODESC_MAX 128 /* Same number as usbfs allows, 2048 bytes. */
164
165/* max number of USB bus supported */
166#define MON_BIN_MAX_MINOR 128
167
168/*
169 * The buffer: map of used pages.
170 */
171struct mon_pgmap {
172 struct page *pg;
173 unsigned char *ptr; /* XXX just use page_to_virt everywhere? */
174};
175
176/*
177 * This gets associated with an open file struct.
178 */
179struct mon_reader_bin {
180 /* The buffer: one per open. */
181 spinlock_t b_lock; /* Protect b_cnt, b_in */
182 unsigned int b_size; /* Current size of the buffer - bytes */
183 unsigned int b_cnt; /* Bytes used */
184 unsigned int b_in, b_out; /* Offsets into buffer - bytes */
185 unsigned int b_read; /* Amount of read data in curr. pkt. */
186 struct mon_pgmap *b_vec; /* The map array */
187 wait_queue_head_t b_wait; /* Wait for data here */
188
189 struct mutex fetch_lock; /* Protect b_read, b_out */
190 int mmap_active;
191
192 /* A list of these is needed for "bus 0". Some time later. */
193 struct mon_reader r;
194
195 /* Stats */
196 unsigned int cnt_lost;
197};
198
199static inline struct mon_bin_hdr *MON_OFF2HDR(const struct mon_reader_bin *rp,
200 unsigned int offset)
201{
202 return (struct mon_bin_hdr *)
203 (rp->b_vec[offset / CHUNK_SIZE].ptr + offset % CHUNK_SIZE);
204}
205
206#define MON_RING_EMPTY(rp) ((rp)->b_cnt == 0)
207
208static unsigned char xfer_to_pipe[4] = {
209 PIPE_CONTROL, PIPE_ISOCHRONOUS, PIPE_BULK, PIPE_INTERRUPT
210};
211
212static struct class *mon_bin_class;
213static dev_t mon_bin_dev0;
214static struct cdev mon_bin_cdev;
215
216static void mon_buff_area_fill(const struct mon_reader_bin *rp,
217 unsigned int offset, unsigned int size);
218static int mon_bin_wait_event(struct file *file, struct mon_reader_bin *rp);
219static int mon_alloc_buff(struct mon_pgmap *map, int npages);
220static void mon_free_buff(struct mon_pgmap *map, int npages);
221
222/*
223 * This is a "chunked memcpy". It does not manipulate any counters.
224 */
225static unsigned int mon_copy_to_buff(const struct mon_reader_bin *this,
226 unsigned int off, const unsigned char *from, unsigned int length)
227{
228 unsigned int step_len;
229 unsigned char *buf;
230 unsigned int in_page;
231
232 while (length) {
233 /*
234 * Determine step_len.
235 */
236 step_len = length;
237 in_page = CHUNK_SIZE - (off & (CHUNK_SIZE-1));
238 if (in_page < step_len)
239 step_len = in_page;
240
241 /*
242 * Copy data and advance pointers.
243 */
244 buf = this->b_vec[off / CHUNK_SIZE].ptr + off % CHUNK_SIZE;
245 memcpy(buf, from, step_len);
246 if ((off += step_len) >= this->b_size) off = 0;
247 from += step_len;
248 length -= step_len;
249 }
250 return off;
251}
252
253/*
254 * This is a little worse than the above because it's "chunked copy_to_user".
255 * The return value is an error code, not an offset.
256 */
257static int copy_from_buf(const struct mon_reader_bin *this, unsigned int off,
258 char __user *to, int length)
259{
260 unsigned int step_len;
261 unsigned char *buf;
262 unsigned int in_page;
263
264 while (length) {
265 /*
266 * Determine step_len.
267 */
268 step_len = length;
269 in_page = CHUNK_SIZE - (off & (CHUNK_SIZE-1));
270 if (in_page < step_len)
271 step_len = in_page;
272
273 /*
274 * Copy data and advance pointers.
275 */
276 buf = this->b_vec[off / CHUNK_SIZE].ptr + off % CHUNK_SIZE;
277 if (copy_to_user(to, buf, step_len))
278 return -EINVAL;
279 if ((off += step_len) >= this->b_size) off = 0;
280 to += step_len;
281 length -= step_len;
282 }
283 return 0;
284}
285
286/*
287 * Allocate an (aligned) area in the buffer.
288 * This is called under b_lock.
289 * Returns ~0 on failure.
290 */
291static unsigned int mon_buff_area_alloc(struct mon_reader_bin *rp,
292 unsigned int size)
293{
294 unsigned int offset;
295
296 size = (size + PKT_ALIGN-1) & ~(PKT_ALIGN-1);
297 if (rp->b_cnt + size > rp->b_size)
298 return ~0;
299 offset = rp->b_in;
300 rp->b_cnt += size;
301 if ((rp->b_in += size) >= rp->b_size)
302 rp->b_in -= rp->b_size;
303 return offset;
304}
305
306/*
307 * This is the same thing as mon_buff_area_alloc, only it does not allow
308 * buffers to wrap. This is needed by applications which pass references
309 * into mmap-ed buffers up their stacks (libpcap can do that).
310 *
311 * Currently, we always have the header stuck with the data, although
312 * it is not strictly speaking necessary.
313 *
314 * When a buffer would wrap, we place a filler packet to mark the space.
315 */
316static unsigned int mon_buff_area_alloc_contiguous(struct mon_reader_bin *rp,
317 unsigned int size)
318{
319 unsigned int offset;
320 unsigned int fill_size;
321
322 size = (size + PKT_ALIGN-1) & ~(PKT_ALIGN-1);
323 if (rp->b_cnt + size > rp->b_size)
324 return ~0;
325 if (rp->b_in + size > rp->b_size) {
326 /*
327 * This would wrap. Find if we still have space after
328 * skipping to the end of the buffer. If we do, place
329 * a filler packet and allocate a new packet.
330 */
331 fill_size = rp->b_size - rp->b_in;
332 if (rp->b_cnt + size + fill_size > rp->b_size)
333 return ~0;
334 mon_buff_area_fill(rp, rp->b_in, fill_size);
335
336 offset = 0;
337 rp->b_in = size;
338 rp->b_cnt += size + fill_size;
339 } else if (rp->b_in + size == rp->b_size) {
340 offset = rp->b_in;
341 rp->b_in = 0;
342 rp->b_cnt += size;
343 } else {
344 offset = rp->b_in;
345 rp->b_in += size;
346 rp->b_cnt += size;
347 }
348 return offset;
349}
350
351/*
352 * Return a few (kilo-)bytes to the head of the buffer.
353 * This is used if a data fetch fails.
354 */
355static void mon_buff_area_shrink(struct mon_reader_bin *rp, unsigned int size)
356{
357
358 /* size &= ~(PKT_ALIGN-1); -- we're called with aligned size */
359 rp->b_cnt -= size;
360 if (rp->b_in < size)
361 rp->b_in += rp->b_size;
362 rp->b_in -= size;
363}
364
365/*
366 * This has to be called under both b_lock and fetch_lock, because
367 * it accesses both b_cnt and b_out.
368 */
369static void mon_buff_area_free(struct mon_reader_bin *rp, unsigned int size)
370{
371
372 size = (size + PKT_ALIGN-1) & ~(PKT_ALIGN-1);
373 rp->b_cnt -= size;
374 if ((rp->b_out += size) >= rp->b_size)
375 rp->b_out -= rp->b_size;
376}
377
378static void mon_buff_area_fill(const struct mon_reader_bin *rp,
379 unsigned int offset, unsigned int size)
380{
381 struct mon_bin_hdr *ep;
382
383 ep = MON_OFF2HDR(rp, offset);
384 memset(ep, 0, PKT_SIZE);
385 ep->type = '@';
386 ep->len_cap = size - PKT_SIZE;
387}
388
389static inline char mon_bin_get_setup(unsigned char *setupb,
390 const struct urb *urb, char ev_type)
391{
392
393 if (urb->setup_packet == NULL)
394 return 'Z';
395 memcpy(setupb, urb->setup_packet, SETUP_LEN);
396 return 0;
397}
398
399static unsigned int mon_bin_get_data(const struct mon_reader_bin *rp,
400 unsigned int offset, struct urb *urb, unsigned int length,
401 char *flag)
402{
403 int i;
404 struct scatterlist *sg;
405 unsigned int this_len;
406
407 *flag = 0;
408 if (urb->num_sgs == 0) {
409 if (urb->transfer_buffer == NULL) {
410 *flag = 'Z';
411 return length;
412 }
413 mon_copy_to_buff(rp, offset, urb->transfer_buffer, length);
414 length = 0;
415
416 } else {
417 /* If IOMMU coalescing occurred, we cannot trust sg_page */
418 if (urb->transfer_flags & URB_DMA_SG_COMBINED) {
419 *flag = 'D';
420 return length;
421 }
422
423 /* Copy up to the first non-addressable segment */
424 for_each_sg(urb->sg, sg, urb->num_sgs, i) {
425 if (length == 0 || PageHighMem(sg_page(sg)))
426 break;
427 this_len = min_t(unsigned int, sg->length, length);
428 offset = mon_copy_to_buff(rp, offset, sg_virt(sg),
429 this_len);
430 length -= this_len;
431 }
432 if (i == 0)
433 *flag = 'D';
434 }
435
436 return length;
437}
438
439/*
440 * This is the look-ahead pass in case of 'C Zi', when actual_length cannot
441 * be used to determine the length of the whole contiguous buffer.
442 */
443static unsigned int mon_bin_collate_isodesc(const struct mon_reader_bin *rp,
444 struct urb *urb, unsigned int ndesc)
445{
446 struct usb_iso_packet_descriptor *fp;
447 unsigned int length;
448
449 length = 0;
450 fp = urb->iso_frame_desc;
451 while (ndesc-- != 0) {
452 if (fp->actual_length != 0) {
453 if (fp->offset + fp->actual_length > length)
454 length = fp->offset + fp->actual_length;
455 }
456 fp++;
457 }
458 return length;
459}
460
461static void mon_bin_get_isodesc(const struct mon_reader_bin *rp,
462 unsigned int offset, struct urb *urb, char ev_type, unsigned int ndesc)
463{
464 struct mon_bin_isodesc *dp;
465 struct usb_iso_packet_descriptor *fp;
466
467 fp = urb->iso_frame_desc;
468 while (ndesc-- != 0) {
469 dp = (struct mon_bin_isodesc *)
470 (rp->b_vec[offset / CHUNK_SIZE].ptr + offset % CHUNK_SIZE);
471 dp->iso_status = fp->status;
472 dp->iso_off = fp->offset;
473 dp->iso_len = (ev_type == 'S') ? fp->length : fp->actual_length;
474 dp->_pad = 0;
475 if ((offset += sizeof(struct mon_bin_isodesc)) >= rp->b_size)
476 offset = 0;
477 fp++;
478 }
479}
480
481static void mon_bin_event(struct mon_reader_bin *rp, struct urb *urb,
482 char ev_type, int status)
483{
484 const struct usb_endpoint_descriptor *epd = &urb->ep->desc;
485 struct timeval ts;
486 unsigned long flags;
487 unsigned int urb_length;
488 unsigned int offset;
489 unsigned int length;
490 unsigned int delta;
491 unsigned int ndesc, lendesc;
492 unsigned char dir;
493 struct mon_bin_hdr *ep;
494 char data_tag = 0;
495
496 do_gettimeofday(&ts);
497
498 spin_lock_irqsave(&rp->b_lock, flags);
499
500 /*
501 * Find the maximum allowable length, then allocate space.
502 */
503 urb_length = (ev_type == 'S') ?
504 urb->transfer_buffer_length : urb->actual_length;
505 length = urb_length;
506
507 if (usb_endpoint_xfer_isoc(epd)) {
508 if (urb->number_of_packets < 0) {
509 ndesc = 0;
510 } else if (urb->number_of_packets >= ISODESC_MAX) {
511 ndesc = ISODESC_MAX;
512 } else {
513 ndesc = urb->number_of_packets;
514 }
515 if (ev_type == 'C' && usb_urb_dir_in(urb))
516 length = mon_bin_collate_isodesc(rp, urb, ndesc);
517 } else {
518 ndesc = 0;
519 }
520 lendesc = ndesc*sizeof(struct mon_bin_isodesc);
521
522 /* not an issue unless there's a subtle bug in a HCD somewhere */
523 if (length >= urb->transfer_buffer_length)
524 length = urb->transfer_buffer_length;
525
526 if (length >= rp->b_size/5)
527 length = rp->b_size/5;
528
529 if (usb_urb_dir_in(urb)) {
530 if (ev_type == 'S') {
531 length = 0;
532 data_tag = '<';
533 }
534 /* Cannot rely on endpoint number in case of control ep.0 */
535 dir = USB_DIR_IN;
536 } else {
537 if (ev_type == 'C') {
538 length = 0;
539 data_tag = '>';
540 }
541 dir = 0;
542 }
543
544 if (rp->mmap_active) {
545 offset = mon_buff_area_alloc_contiguous(rp,
546 length + PKT_SIZE + lendesc);
547 } else {
548 offset = mon_buff_area_alloc(rp, length + PKT_SIZE + lendesc);
549 }
550 if (offset == ~0) {
551 rp->cnt_lost++;
552 spin_unlock_irqrestore(&rp->b_lock, flags);
553 return;
554 }
555
556 ep = MON_OFF2HDR(rp, offset);
557 if ((offset += PKT_SIZE) >= rp->b_size) offset = 0;
558
559 /*
560 * Fill the allocated area.
561 */
562 memset(ep, 0, PKT_SIZE);
563 ep->type = ev_type;
564 ep->xfer_type = xfer_to_pipe[usb_endpoint_type(epd)];
565 ep->epnum = dir | usb_endpoint_num(epd);
566 ep->devnum = urb->dev->devnum;
567 ep->busnum = urb->dev->bus->busnum;
568 ep->id = (unsigned long) urb;
569 ep->ts_sec = ts.tv_sec;
570 ep->ts_usec = ts.tv_usec;
571 ep->status = status;
572 ep->len_urb = urb_length;
573 ep->len_cap = length + lendesc;
574 ep->xfer_flags = urb->transfer_flags;
575
576 if (usb_endpoint_xfer_int(epd)) {
577 ep->interval = urb->interval;
578 } else if (usb_endpoint_xfer_isoc(epd)) {
579 ep->interval = urb->interval;
580 ep->start_frame = urb->start_frame;
581 ep->s.iso.error_count = urb->error_count;
582 ep->s.iso.numdesc = urb->number_of_packets;
583 }
584
585 if (usb_endpoint_xfer_control(epd) && ev_type == 'S') {
586 ep->flag_setup = mon_bin_get_setup(ep->s.setup, urb, ev_type);
587 } else {
588 ep->flag_setup = '-';
589 }
590
591 if (ndesc != 0) {
592 ep->ndesc = ndesc;
593 mon_bin_get_isodesc(rp, offset, urb, ev_type, ndesc);
594 if ((offset += lendesc) >= rp->b_size)
595 offset -= rp->b_size;
596 }
597
598 if (length != 0) {
599 length = mon_bin_get_data(rp, offset, urb, length,
600 &ep->flag_data);
601 if (length > 0) {
602 delta = (ep->len_cap + PKT_ALIGN-1) & ~(PKT_ALIGN-1);
603 ep->len_cap -= length;
604 delta -= (ep->len_cap + PKT_ALIGN-1) & ~(PKT_ALIGN-1);
605 mon_buff_area_shrink(rp, delta);
606 }
607 } else {
608 ep->flag_data = data_tag;
609 }
610
611 spin_unlock_irqrestore(&rp->b_lock, flags);
612
613 wake_up(&rp->b_wait);
614}
615
616static void mon_bin_submit(void *data, struct urb *urb)
617{
618 struct mon_reader_bin *rp = data;
619 mon_bin_event(rp, urb, 'S', -EINPROGRESS);
620}
621
622static void mon_bin_complete(void *data, struct urb *urb, int status)
623{
624 struct mon_reader_bin *rp = data;
625 mon_bin_event(rp, urb, 'C', status);
626}
627
628static void mon_bin_error(void *data, struct urb *urb, int error)
629{
630 struct mon_reader_bin *rp = data;
631 struct timeval ts;
632 unsigned long flags;
633 unsigned int offset;
634 struct mon_bin_hdr *ep;
635
636 do_gettimeofday(&ts);
637
638 spin_lock_irqsave(&rp->b_lock, flags);
639
640 offset = mon_buff_area_alloc(rp, PKT_SIZE);
641 if (offset == ~0) {
642 /* Not incrementing cnt_lost. Just because. */
643 spin_unlock_irqrestore(&rp->b_lock, flags);
644 return;
645 }
646
647 ep = MON_OFF2HDR(rp, offset);
648
649 memset(ep, 0, PKT_SIZE);
650 ep->type = 'E';
651 ep->xfer_type = xfer_to_pipe[usb_endpoint_type(&urb->ep->desc)];
652 ep->epnum = usb_urb_dir_in(urb) ? USB_DIR_IN : 0;
653 ep->epnum |= usb_endpoint_num(&urb->ep->desc);
654 ep->devnum = urb->dev->devnum;
655 ep->busnum = urb->dev->bus->busnum;
656 ep->id = (unsigned long) urb;
657 ep->ts_sec = ts.tv_sec;
658 ep->ts_usec = ts.tv_usec;
659 ep->status = error;
660
661 ep->flag_setup = '-';
662 ep->flag_data = 'E';
663
664 spin_unlock_irqrestore(&rp->b_lock, flags);
665
666 wake_up(&rp->b_wait);
667}
668
669static int mon_bin_open(struct inode *inode, struct file *file)
670{
671 struct mon_bus *mbus;
672 struct mon_reader_bin *rp;
673 size_t size;
674 int rc;
675
676 mutex_lock(&mon_lock);
677 if ((mbus = mon_bus_lookup(iminor(inode))) == NULL) {
678 mutex_unlock(&mon_lock);
679 return -ENODEV;
680 }
681 if (mbus != &mon_bus0 && mbus->u_bus == NULL) {
682 printk(KERN_ERR TAG ": consistency error on open\n");
683 mutex_unlock(&mon_lock);
684 return -ENODEV;
685 }
686
687 rp = kzalloc(sizeof(struct mon_reader_bin), GFP_KERNEL);
688 if (rp == NULL) {
689 rc = -ENOMEM;
690 goto err_alloc;
691 }
692 spin_lock_init(&rp->b_lock);
693 init_waitqueue_head(&rp->b_wait);
694 mutex_init(&rp->fetch_lock);
695 rp->b_size = BUFF_DFL;
696
697 size = sizeof(struct mon_pgmap) * (rp->b_size/CHUNK_SIZE);
698 if ((rp->b_vec = kzalloc(size, GFP_KERNEL)) == NULL) {
699 rc = -ENOMEM;
700 goto err_allocvec;
701 }
702
703 if ((rc = mon_alloc_buff(rp->b_vec, rp->b_size/CHUNK_SIZE)) < 0)
704 goto err_allocbuff;
705
706 rp->r.m_bus = mbus;
707 rp->r.r_data = rp;
708 rp->r.rnf_submit = mon_bin_submit;
709 rp->r.rnf_error = mon_bin_error;
710 rp->r.rnf_complete = mon_bin_complete;
711
712 mon_reader_add(mbus, &rp->r);
713
714 file->private_data = rp;
715 mutex_unlock(&mon_lock);
716 return 0;
717
718err_allocbuff:
719 kfree(rp->b_vec);
720err_allocvec:
721 kfree(rp);
722err_alloc:
723 mutex_unlock(&mon_lock);
724 return rc;
725}
726
727/*
728 * Extract an event from buffer and copy it to user space.
729 * Wait if there is no event ready.
730 * Returns zero or error.
731 */
732static int mon_bin_get_event(struct file *file, struct mon_reader_bin *rp,
733 struct mon_bin_hdr __user *hdr, unsigned int hdrbytes,
734 void __user *data, unsigned int nbytes)
735{
736 unsigned long flags;
737 struct mon_bin_hdr *ep;
738 size_t step_len;
739 unsigned int offset;
740 int rc;
741
742 mutex_lock(&rp->fetch_lock);
743
744 if ((rc = mon_bin_wait_event(file, rp)) < 0) {
745 mutex_unlock(&rp->fetch_lock);
746 return rc;
747 }
748
749 ep = MON_OFF2HDR(rp, rp->b_out);
750
751 if (copy_to_user(hdr, ep, hdrbytes)) {
752 mutex_unlock(&rp->fetch_lock);
753 return -EFAULT;
754 }
755
756 step_len = min(ep->len_cap, nbytes);
757 if ((offset = rp->b_out + PKT_SIZE) >= rp->b_size) offset = 0;
758
759 if (copy_from_buf(rp, offset, data, step_len)) {
760 mutex_unlock(&rp->fetch_lock);
761 return -EFAULT;
762 }
763
764 spin_lock_irqsave(&rp->b_lock, flags);
765 mon_buff_area_free(rp, PKT_SIZE + ep->len_cap);
766 spin_unlock_irqrestore(&rp->b_lock, flags);
767 rp->b_read = 0;
768
769 mutex_unlock(&rp->fetch_lock);
770 return 0;
771}
772
773static int mon_bin_release(struct inode *inode, struct file *file)
774{
775 struct mon_reader_bin *rp = file->private_data;
776 struct mon_bus* mbus = rp->r.m_bus;
777
778 mutex_lock(&mon_lock);
779
780 if (mbus->nreaders <= 0) {
781 printk(KERN_ERR TAG ": consistency error on close\n");
782 mutex_unlock(&mon_lock);
783 return 0;
784 }
785 mon_reader_del(mbus, &rp->r);
786
787 mon_free_buff(rp->b_vec, rp->b_size/CHUNK_SIZE);
788 kfree(rp->b_vec);
789 kfree(rp);
790
791 mutex_unlock(&mon_lock);
792 return 0;
793}
794
795static ssize_t mon_bin_read(struct file *file, char __user *buf,
796 size_t nbytes, loff_t *ppos)
797{
798 struct mon_reader_bin *rp = file->private_data;
799 unsigned int hdrbytes = PKT_SZ_API0;
800 unsigned long flags;
801 struct mon_bin_hdr *ep;
802 unsigned int offset;
803 size_t step_len;
804 char *ptr;
805 ssize_t done = 0;
806 int rc;
807
808 mutex_lock(&rp->fetch_lock);
809
810 if ((rc = mon_bin_wait_event(file, rp)) < 0) {
811 mutex_unlock(&rp->fetch_lock);
812 return rc;
813 }
814
815 ep = MON_OFF2HDR(rp, rp->b_out);
816
817 if (rp->b_read < hdrbytes) {
818 step_len = min(nbytes, (size_t)(hdrbytes - rp->b_read));
819 ptr = ((char *)ep) + rp->b_read;
820 if (step_len && copy_to_user(buf, ptr, step_len)) {
821 mutex_unlock(&rp->fetch_lock);
822 return -EFAULT;
823 }
824 nbytes -= step_len;
825 buf += step_len;
826 rp->b_read += step_len;
827 done += step_len;
828 }
829
830 if (rp->b_read >= hdrbytes) {
831 step_len = ep->len_cap;
832 step_len -= rp->b_read - hdrbytes;
833 if (step_len > nbytes)
834 step_len = nbytes;
835 offset = rp->b_out + PKT_SIZE;
836 offset += rp->b_read - hdrbytes;
837 if (offset >= rp->b_size)
838 offset -= rp->b_size;
839 if (copy_from_buf(rp, offset, buf, step_len)) {
840 mutex_unlock(&rp->fetch_lock);
841 return -EFAULT;
842 }
843 nbytes -= step_len;
844 buf += step_len;
845 rp->b_read += step_len;
846 done += step_len;
847 }
848
849 /*
850 * Check if whole packet was read, and if so, jump to the next one.
851 */
852 if (rp->b_read >= hdrbytes + ep->len_cap) {
853 spin_lock_irqsave(&rp->b_lock, flags);
854 mon_buff_area_free(rp, PKT_SIZE + ep->len_cap);
855 spin_unlock_irqrestore(&rp->b_lock, flags);
856 rp->b_read = 0;
857 }
858
859 mutex_unlock(&rp->fetch_lock);
860 return done;
861}
862
863/*
864 * Remove at most nevents from chunked buffer.
865 * Returns the number of removed events.
866 */
867static int mon_bin_flush(struct mon_reader_bin *rp, unsigned nevents)
868{
869 unsigned long flags;
870 struct mon_bin_hdr *ep;
871 int i;
872
873 mutex_lock(&rp->fetch_lock);
874 spin_lock_irqsave(&rp->b_lock, flags);
875 for (i = 0; i < nevents; ++i) {
876 if (MON_RING_EMPTY(rp))
877 break;
878
879 ep = MON_OFF2HDR(rp, rp->b_out);
880 mon_buff_area_free(rp, PKT_SIZE + ep->len_cap);
881 }
882 spin_unlock_irqrestore(&rp->b_lock, flags);
883 rp->b_read = 0;
884 mutex_unlock(&rp->fetch_lock);
885 return i;
886}
887
888/*
889 * Fetch at most max event offsets into the buffer and put them into vec.
890 * The events are usually freed later with mon_bin_flush.
891 * Return the effective number of events fetched.
892 */
893static int mon_bin_fetch(struct file *file, struct mon_reader_bin *rp,
894 u32 __user *vec, unsigned int max)
895{
896 unsigned int cur_out;
897 unsigned int bytes, avail;
898 unsigned int size;
899 unsigned int nevents;
900 struct mon_bin_hdr *ep;
901 unsigned long flags;
902 int rc;
903
904 mutex_lock(&rp->fetch_lock);
905
906 if ((rc = mon_bin_wait_event(file, rp)) < 0) {
907 mutex_unlock(&rp->fetch_lock);
908 return rc;
909 }
910
911 spin_lock_irqsave(&rp->b_lock, flags);
912 avail = rp->b_cnt;
913 spin_unlock_irqrestore(&rp->b_lock, flags);
914
915 cur_out = rp->b_out;
916 nevents = 0;
917 bytes = 0;
918 while (bytes < avail) {
919 if (nevents >= max)
920 break;
921
922 ep = MON_OFF2HDR(rp, cur_out);
923 if (put_user(cur_out, &vec[nevents])) {
924 mutex_unlock(&rp->fetch_lock);
925 return -EFAULT;
926 }
927
928 nevents++;
929 size = ep->len_cap + PKT_SIZE;
930 size = (size + PKT_ALIGN-1) & ~(PKT_ALIGN-1);
931 if ((cur_out += size) >= rp->b_size)
932 cur_out -= rp->b_size;
933 bytes += size;
934 }
935
936 mutex_unlock(&rp->fetch_lock);
937 return nevents;
938}
939
940/*
941 * Count events. This is almost the same as the above mon_bin_fetch,
942 * only we do not store offsets into user vector, and we have no limit.
943 */
944static int mon_bin_queued(struct mon_reader_bin *rp)
945{
946 unsigned int cur_out;
947 unsigned int bytes, avail;
948 unsigned int size;
949 unsigned int nevents;
950 struct mon_bin_hdr *ep;
951 unsigned long flags;
952
953 mutex_lock(&rp->fetch_lock);
954
955 spin_lock_irqsave(&rp->b_lock, flags);
956 avail = rp->b_cnt;
957 spin_unlock_irqrestore(&rp->b_lock, flags);
958
959 cur_out = rp->b_out;
960 nevents = 0;
961 bytes = 0;
962 while (bytes < avail) {
963 ep = MON_OFF2HDR(rp, cur_out);
964
965 nevents++;
966 size = ep->len_cap + PKT_SIZE;
967 size = (size + PKT_ALIGN-1) & ~(PKT_ALIGN-1);
968 if ((cur_out += size) >= rp->b_size)
969 cur_out -= rp->b_size;
970 bytes += size;
971 }
972
973 mutex_unlock(&rp->fetch_lock);
974 return nevents;
975}
976
977/*
978 */
979static long mon_bin_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
980{
981 struct mon_reader_bin *rp = file->private_data;
982 // struct mon_bus* mbus = rp->r.m_bus;
983 int ret = 0;
984 struct mon_bin_hdr *ep;
985 unsigned long flags;
986
987 switch (cmd) {
988
989 case MON_IOCQ_URB_LEN:
990 /*
991 * N.B. This only returns the size of data, without the header.
992 */
993 spin_lock_irqsave(&rp->b_lock, flags);
994 if (!MON_RING_EMPTY(rp)) {
995 ep = MON_OFF2HDR(rp, rp->b_out);
996 ret = ep->len_cap;
997 }
998 spin_unlock_irqrestore(&rp->b_lock, flags);
999 break;
1000
1001 case MON_IOCQ_RING_SIZE:
1002 ret = rp->b_size;
1003 break;
1004
1005 case MON_IOCT_RING_SIZE:
1006 /*
1007 * Changing the buffer size will flush it's contents; the new
1008 * buffer is allocated before releasing the old one to be sure
1009 * the device will stay functional also in case of memory
1010 * pressure.
1011 */
1012 {
1013 int size;
1014 struct mon_pgmap *vec;
1015
1016 if (arg < BUFF_MIN || arg > BUFF_MAX)
1017 return -EINVAL;
1018
1019 size = CHUNK_ALIGN(arg);
1020 if ((vec = kzalloc(sizeof(struct mon_pgmap) * (size/CHUNK_SIZE),
1021 GFP_KERNEL)) == NULL) {
1022 ret = -ENOMEM;
1023 break;
1024 }
1025
1026 ret = mon_alloc_buff(vec, size/CHUNK_SIZE);
1027 if (ret < 0) {
1028 kfree(vec);
1029 break;
1030 }
1031
1032 mutex_lock(&rp->fetch_lock);
1033 spin_lock_irqsave(&rp->b_lock, flags);
1034 mon_free_buff(rp->b_vec, rp->b_size/CHUNK_SIZE);
1035 kfree(rp->b_vec);
1036 rp->b_vec = vec;
1037 rp->b_size = size;
1038 rp->b_read = rp->b_in = rp->b_out = rp->b_cnt = 0;
1039 rp->cnt_lost = 0;
1040 spin_unlock_irqrestore(&rp->b_lock, flags);
1041 mutex_unlock(&rp->fetch_lock);
1042 }
1043 break;
1044
1045 case MON_IOCH_MFLUSH:
1046 ret = mon_bin_flush(rp, arg);
1047 break;
1048
1049 case MON_IOCX_GET:
1050 case MON_IOCX_GETX:
1051 {
1052 struct mon_bin_get getb;
1053
1054 if (copy_from_user(&getb, (void __user *)arg,
1055 sizeof(struct mon_bin_get)))
1056 return -EFAULT;
1057
1058 if (getb.alloc > 0x10000000) /* Want to cast to u32 */
1059 return -EINVAL;
1060 ret = mon_bin_get_event(file, rp, getb.hdr,
1061 (cmd == MON_IOCX_GET)? PKT_SZ_API0: PKT_SZ_API1,
1062 getb.data, (unsigned int)getb.alloc);
1063 }
1064 break;
1065
1066 case MON_IOCX_MFETCH:
1067 {
1068 struct mon_bin_mfetch mfetch;
1069 struct mon_bin_mfetch __user *uptr;
1070
1071 uptr = (struct mon_bin_mfetch __user *)arg;
1072
1073 if (copy_from_user(&mfetch, uptr, sizeof(mfetch)))
1074 return -EFAULT;
1075
1076 if (mfetch.nflush) {
1077 ret = mon_bin_flush(rp, mfetch.nflush);
1078 if (ret < 0)
1079 return ret;
1080 if (put_user(ret, &uptr->nflush))
1081 return -EFAULT;
1082 }
1083 ret = mon_bin_fetch(file, rp, mfetch.offvec, mfetch.nfetch);
1084 if (ret < 0)
1085 return ret;
1086 if (put_user(ret, &uptr->nfetch))
1087 return -EFAULT;
1088 ret = 0;
1089 }
1090 break;
1091
1092 case MON_IOCG_STATS: {
1093 struct mon_bin_stats __user *sp;
1094 unsigned int nevents;
1095 unsigned int ndropped;
1096
1097 spin_lock_irqsave(&rp->b_lock, flags);
1098 ndropped = rp->cnt_lost;
1099 rp->cnt_lost = 0;
1100 spin_unlock_irqrestore(&rp->b_lock, flags);
1101 nevents = mon_bin_queued(rp);
1102
1103 sp = (struct mon_bin_stats __user *)arg;
1104 if (put_user(rp->cnt_lost, &sp->dropped))
1105 return -EFAULT;
1106 if (put_user(nevents, &sp->queued))
1107 return -EFAULT;
1108
1109 }
1110 break;
1111
1112 default:
1113 return -ENOTTY;
1114 }
1115
1116 return ret;
1117}
1118
1119#ifdef CONFIG_COMPAT
1120static long mon_bin_compat_ioctl(struct file *file,
1121 unsigned int cmd, unsigned long arg)
1122{
1123 struct mon_reader_bin *rp = file->private_data;
1124 int ret;
1125
1126 switch (cmd) {
1127
1128 case MON_IOCX_GET32:
1129 case MON_IOCX_GETX32:
1130 {
1131 struct mon_bin_get32 getb;
1132
1133 if (copy_from_user(&getb, (void __user *)arg,
1134 sizeof(struct mon_bin_get32)))
1135 return -EFAULT;
1136
1137 ret = mon_bin_get_event(file, rp, compat_ptr(getb.hdr32),
1138 (cmd == MON_IOCX_GET32)? PKT_SZ_API0: PKT_SZ_API1,
1139 compat_ptr(getb.data32), getb.alloc32);
1140 if (ret < 0)
1141 return ret;
1142 }
1143 return 0;
1144
1145 case MON_IOCX_MFETCH32:
1146 {
1147 struct mon_bin_mfetch32 mfetch;
1148 struct mon_bin_mfetch32 __user *uptr;
1149
1150 uptr = (struct mon_bin_mfetch32 __user *) compat_ptr(arg);
1151
1152 if (copy_from_user(&mfetch, uptr, sizeof(mfetch)))
1153 return -EFAULT;
1154
1155 if (mfetch.nflush32) {
1156 ret = mon_bin_flush(rp, mfetch.nflush32);
1157 if (ret < 0)
1158 return ret;
1159 if (put_user(ret, &uptr->nflush32))
1160 return -EFAULT;
1161 }
1162 ret = mon_bin_fetch(file, rp, compat_ptr(mfetch.offvec32),
1163 mfetch.nfetch32);
1164 if (ret < 0)
1165 return ret;
1166 if (put_user(ret, &uptr->nfetch32))
1167 return -EFAULT;
1168 }
1169 return 0;
1170
1171 case MON_IOCG_STATS:
1172 return mon_bin_ioctl(file, cmd, (unsigned long) compat_ptr(arg));
1173
1174 case MON_IOCQ_URB_LEN:
1175 case MON_IOCQ_RING_SIZE:
1176 case MON_IOCT_RING_SIZE:
1177 case MON_IOCH_MFLUSH:
1178 return mon_bin_ioctl(file, cmd, arg);
1179
1180 default:
1181 ;
1182 }
1183 return -ENOTTY;
1184}
1185#endif /* CONFIG_COMPAT */
1186
1187static unsigned int
1188mon_bin_poll(struct file *file, struct poll_table_struct *wait)
1189{
1190 struct mon_reader_bin *rp = file->private_data;
1191 unsigned int mask = 0;
1192 unsigned long flags;
1193
1194 if (file->f_mode & FMODE_READ)
1195 poll_wait(file, &rp->b_wait, wait);
1196
1197 spin_lock_irqsave(&rp->b_lock, flags);
1198 if (!MON_RING_EMPTY(rp))
1199 mask |= POLLIN | POLLRDNORM; /* readable */
1200 spin_unlock_irqrestore(&rp->b_lock, flags);
1201 return mask;
1202}
1203
1204/*
1205 * open and close: just keep track of how many times the device is
1206 * mapped, to use the proper memory allocation function.
1207 */
1208static void mon_bin_vma_open(struct vm_area_struct *vma)
1209{
1210 struct mon_reader_bin *rp = vma->vm_private_data;
1211 rp->mmap_active++;
1212}
1213
1214static void mon_bin_vma_close(struct vm_area_struct *vma)
1215{
1216 struct mon_reader_bin *rp = vma->vm_private_data;
1217 rp->mmap_active--;
1218}
1219
1220/*
1221 * Map ring pages to user space.
1222 */
1223static int mon_bin_vma_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
1224{
1225 struct mon_reader_bin *rp = vma->vm_private_data;
1226 unsigned long offset, chunk_idx;
1227 struct page *pageptr;
1228
1229 offset = vmf->pgoff << PAGE_SHIFT;
1230 if (offset >= rp->b_size)
1231 return VM_FAULT_SIGBUS;
1232 chunk_idx = offset / CHUNK_SIZE;
1233 pageptr = rp->b_vec[chunk_idx].pg;
1234 get_page(pageptr);
1235 vmf->page = pageptr;
1236 return 0;
1237}
1238
1239static const struct vm_operations_struct mon_bin_vm_ops = {
1240 .open = mon_bin_vma_open,
1241 .close = mon_bin_vma_close,
1242 .fault = mon_bin_vma_fault,
1243};
1244
1245static int mon_bin_mmap(struct file *filp, struct vm_area_struct *vma)
1246{
1247 /* don't do anything here: "fault" will set up page table entries */
1248 vma->vm_ops = &mon_bin_vm_ops;
1249 vma->vm_flags |= VM_RESERVED;
1250 vma->vm_private_data = filp->private_data;
1251 mon_bin_vma_open(vma);
1252 return 0;
1253}
1254
1255static const struct file_operations mon_fops_binary = {
1256 .owner = THIS_MODULE,
1257 .open = mon_bin_open,
1258 .llseek = no_llseek,
1259 .read = mon_bin_read,
1260 /* .write = mon_text_write, */
1261 .poll = mon_bin_poll,
1262 .unlocked_ioctl = mon_bin_ioctl,
1263#ifdef CONFIG_COMPAT
1264 .compat_ioctl = mon_bin_compat_ioctl,
1265#endif
1266 .release = mon_bin_release,
1267 .mmap = mon_bin_mmap,
1268};
1269
1270static int mon_bin_wait_event(struct file *file, struct mon_reader_bin *rp)
1271{
1272 DECLARE_WAITQUEUE(waita, current);
1273 unsigned long flags;
1274
1275 add_wait_queue(&rp->b_wait, &waita);
1276 set_current_state(TASK_INTERRUPTIBLE);
1277
1278 spin_lock_irqsave(&rp->b_lock, flags);
1279 while (MON_RING_EMPTY(rp)) {
1280 spin_unlock_irqrestore(&rp->b_lock, flags);
1281
1282 if (file->f_flags & O_NONBLOCK) {
1283 set_current_state(TASK_RUNNING);
1284 remove_wait_queue(&rp->b_wait, &waita);
1285 return -EWOULDBLOCK; /* Same as EAGAIN in Linux */
1286 }
1287 schedule();
1288 if (signal_pending(current)) {
1289 remove_wait_queue(&rp->b_wait, &waita);
1290 return -EINTR;
1291 }
1292 set_current_state(TASK_INTERRUPTIBLE);
1293
1294 spin_lock_irqsave(&rp->b_lock, flags);
1295 }
1296 spin_unlock_irqrestore(&rp->b_lock, flags);
1297
1298 set_current_state(TASK_RUNNING);
1299 remove_wait_queue(&rp->b_wait, &waita);
1300 return 0;
1301}
1302
1303static int mon_alloc_buff(struct mon_pgmap *map, int npages)
1304{
1305 int n;
1306 unsigned long vaddr;
1307
1308 for (n = 0; n < npages; n++) {
1309 vaddr = get_zeroed_page(GFP_KERNEL);
1310 if (vaddr == 0) {
1311 while (n-- != 0)
1312 free_page((unsigned long) map[n].ptr);
1313 return -ENOMEM;
1314 }
1315 map[n].ptr = (unsigned char *) vaddr;
1316 map[n].pg = virt_to_page((void *) vaddr);
1317 }
1318 return 0;
1319}
1320
1321static void mon_free_buff(struct mon_pgmap *map, int npages)
1322{
1323 int n;
1324
1325 for (n = 0; n < npages; n++)
1326 free_page((unsigned long) map[n].ptr);
1327}
1328
1329int mon_bin_add(struct mon_bus *mbus, const struct usb_bus *ubus)
1330{
1331 struct device *dev;
1332 unsigned minor = ubus? ubus->busnum: 0;
1333
1334 if (minor >= MON_BIN_MAX_MINOR)
1335 return 0;
1336
1337 dev = device_create(mon_bin_class, ubus ? ubus->controller : NULL,
1338 MKDEV(MAJOR(mon_bin_dev0), minor), NULL,
1339 "usbmon%d", minor);
1340 if (IS_ERR(dev))
1341 return 0;
1342
1343 mbus->classdev = dev;
1344 return 1;
1345}
1346
1347void mon_bin_del(struct mon_bus *mbus)
1348{
1349 device_destroy(mon_bin_class, mbus->classdev->devt);
1350}
1351
1352int __init mon_bin_init(void)
1353{
1354 int rc;
1355
1356 mon_bin_class = class_create(THIS_MODULE, "usbmon");
1357 if (IS_ERR(mon_bin_class)) {
1358 rc = PTR_ERR(mon_bin_class);
1359 goto err_class;
1360 }
1361
1362 rc = alloc_chrdev_region(&mon_bin_dev0, 0, MON_BIN_MAX_MINOR, "usbmon");
1363 if (rc < 0)
1364 goto err_dev;
1365
1366 cdev_init(&mon_bin_cdev, &mon_fops_binary);
1367 mon_bin_cdev.owner = THIS_MODULE;
1368
1369 rc = cdev_add(&mon_bin_cdev, mon_bin_dev0, MON_BIN_MAX_MINOR);
1370 if (rc < 0)
1371 goto err_add;
1372
1373 return 0;
1374
1375err_add:
1376 unregister_chrdev_region(mon_bin_dev0, MON_BIN_MAX_MINOR);
1377err_dev:
1378 class_destroy(mon_bin_class);
1379err_class:
1380 return rc;
1381}
1382
1383void mon_bin_exit(void)
1384{
1385 cdev_del(&mon_bin_cdev);
1386 unregister_chrdev_region(mon_bin_dev0, MON_BIN_MAX_MINOR);
1387 class_destroy(mon_bin_class);
1388}
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * The USB Monitor, inspired by Dave Harding's USBMon.
4 *
5 * This is a binary format reader.
6 *
7 * Copyright (C) 2006 Paolo Abeni (paolo.abeni@email.it)
8 * Copyright (C) 2006,2007 Pete Zaitcev (zaitcev@redhat.com)
9 */
10
11#include <linux/kernel.h>
12#include <linux/sched/signal.h>
13#include <linux/types.h>
14#include <linux/fs.h>
15#include <linux/cdev.h>
16#include <linux/export.h>
17#include <linux/usb.h>
18#include <linux/poll.h>
19#include <linux/compat.h>
20#include <linux/mm.h>
21#include <linux/scatterlist.h>
22#include <linux/slab.h>
23#include <linux/time64.h>
24
25#include <linux/uaccess.h>
26
27#include "usb_mon.h"
28
29/*
30 * Defined by USB 2.0 clause 9.3, table 9.2.
31 */
32#define SETUP_LEN 8
33
34/* ioctl macros */
35#define MON_IOC_MAGIC 0x92
36
37#define MON_IOCQ_URB_LEN _IO(MON_IOC_MAGIC, 1)
38/* #2 used to be MON_IOCX_URB, removed before it got into Linus tree */
39#define MON_IOCG_STATS _IOR(MON_IOC_MAGIC, 3, struct mon_bin_stats)
40#define MON_IOCT_RING_SIZE _IO(MON_IOC_MAGIC, 4)
41#define MON_IOCQ_RING_SIZE _IO(MON_IOC_MAGIC, 5)
42#define MON_IOCX_GET _IOW(MON_IOC_MAGIC, 6, struct mon_bin_get)
43#define MON_IOCX_MFETCH _IOWR(MON_IOC_MAGIC, 7, struct mon_bin_mfetch)
44#define MON_IOCH_MFLUSH _IO(MON_IOC_MAGIC, 8)
45/* #9 was MON_IOCT_SETAPI */
46#define MON_IOCX_GETX _IOW(MON_IOC_MAGIC, 10, struct mon_bin_get)
47
48#ifdef CONFIG_COMPAT
49#define MON_IOCX_GET32 _IOW(MON_IOC_MAGIC, 6, struct mon_bin_get32)
50#define MON_IOCX_MFETCH32 _IOWR(MON_IOC_MAGIC, 7, struct mon_bin_mfetch32)
51#define MON_IOCX_GETX32 _IOW(MON_IOC_MAGIC, 10, struct mon_bin_get32)
52#endif
53
54/*
55 * Some architectures have enormous basic pages (16KB for ia64, 64KB for ppc).
56 * But it's all right. Just use a simple way to make sure the chunk is never
57 * smaller than a page.
58 *
59 * N.B. An application does not know our chunk size.
60 *
61 * Woops, get_zeroed_page() returns a single page. I guess we're stuck with
62 * page-sized chunks for the time being.
63 */
64#define CHUNK_SIZE PAGE_SIZE
65#define CHUNK_ALIGN(x) (((x)+CHUNK_SIZE-1) & ~(CHUNK_SIZE-1))
66
67/*
68 * The magic limit was calculated so that it allows the monitoring
69 * application to pick data once in two ticks. This way, another application,
70 * which presumably drives the bus, gets to hog CPU, yet we collect our data.
71 * If HZ is 100, a 480 mbit/s bus drives 614 KB every jiffy. USB has an
72 * enormous overhead built into the bus protocol, so we need about 1000 KB.
73 *
74 * This is still too much for most cases, where we just snoop a few
75 * descriptor fetches for enumeration. So, the default is a "reasonable"
76 * amount for systems with HZ=250 and incomplete bus saturation.
77 *
78 * XXX What about multi-megabyte URBs which take minutes to transfer?
79 */
80#define BUFF_MAX CHUNK_ALIGN(1200*1024)
81#define BUFF_DFL CHUNK_ALIGN(300*1024)
82#define BUFF_MIN CHUNK_ALIGN(8*1024)
83
84/*
85 * The per-event API header (2 per URB).
86 *
87 * This structure is seen in userland as defined by the documentation.
88 */
89struct mon_bin_hdr {
90 u64 id; /* URB ID - from submission to callback */
91 unsigned char type; /* Same as in text API; extensible. */
92 unsigned char xfer_type; /* ISO, Intr, Control, Bulk */
93 unsigned char epnum; /* Endpoint number and transfer direction */
94 unsigned char devnum; /* Device address */
95 unsigned short busnum; /* Bus number */
96 char flag_setup;
97 char flag_data;
98 s64 ts_sec; /* ktime_get_real_ts64 */
99 s32 ts_usec; /* ktime_get_real_ts64 */
100 int status;
101 unsigned int len_urb; /* Length of data (submitted or actual) */
102 unsigned int len_cap; /* Delivered length */
103 union {
104 unsigned char setup[SETUP_LEN]; /* Only for Control S-type */
105 struct iso_rec {
106 int error_count;
107 int numdesc;
108 } iso;
109 } s;
110 int interval;
111 int start_frame;
112 unsigned int xfer_flags;
113 unsigned int ndesc; /* Actual number of ISO descriptors */
114};
115
116/*
117 * ISO vector, packed into the head of data stream.
118 * This has to take 16 bytes to make sure that the end of buffer
119 * wrap is not happening in the middle of a descriptor.
120 */
121struct mon_bin_isodesc {
122 int iso_status;
123 unsigned int iso_off;
124 unsigned int iso_len;
125 u32 _pad;
126};
127
128/* per file statistic */
129struct mon_bin_stats {
130 u32 queued;
131 u32 dropped;
132};
133
134struct mon_bin_get {
135 struct mon_bin_hdr __user *hdr; /* Can be 48 bytes or 64. */
136 void __user *data;
137 size_t alloc; /* Length of data (can be zero) */
138};
139
140struct mon_bin_mfetch {
141 u32 __user *offvec; /* Vector of events fetched */
142 u32 nfetch; /* Number of events to fetch (out: fetched) */
143 u32 nflush; /* Number of events to flush */
144};
145
146#ifdef CONFIG_COMPAT
147struct mon_bin_get32 {
148 u32 hdr32;
149 u32 data32;
150 u32 alloc32;
151};
152
153struct mon_bin_mfetch32 {
154 u32 offvec32;
155 u32 nfetch32;
156 u32 nflush32;
157};
158#endif
159
160/* Having these two values same prevents wrapping of the mon_bin_hdr */
161#define PKT_ALIGN 64
162#define PKT_SIZE 64
163
164#define PKT_SZ_API0 48 /* API 0 (2.6.20) size */
165#define PKT_SZ_API1 64 /* API 1 size: extra fields */
166
167#define ISODESC_MAX 128 /* Same number as usbfs allows, 2048 bytes. */
168
169/* max number of USB bus supported */
170#define MON_BIN_MAX_MINOR 128
171
172/*
173 * The buffer: map of used pages.
174 */
175struct mon_pgmap {
176 struct page *pg;
177 unsigned char *ptr; /* XXX just use page_to_virt everywhere? */
178};
179
180/*
181 * This gets associated with an open file struct.
182 */
183struct mon_reader_bin {
184 /* The buffer: one per open. */
185 spinlock_t b_lock; /* Protect b_cnt, b_in */
186 unsigned int b_size; /* Current size of the buffer - bytes */
187 unsigned int b_cnt; /* Bytes used */
188 unsigned int b_in, b_out; /* Offsets into buffer - bytes */
189 unsigned int b_read; /* Amount of read data in curr. pkt. */
190 struct mon_pgmap *b_vec; /* The map array */
191 wait_queue_head_t b_wait; /* Wait for data here */
192
193 struct mutex fetch_lock; /* Protect b_read, b_out */
194 int mmap_active;
195
196 /* A list of these is needed for "bus 0". Some time later. */
197 struct mon_reader r;
198
199 /* Stats */
200 unsigned int cnt_lost;
201};
202
203static inline struct mon_bin_hdr *MON_OFF2HDR(const struct mon_reader_bin *rp,
204 unsigned int offset)
205{
206 return (struct mon_bin_hdr *)
207 (rp->b_vec[offset / CHUNK_SIZE].ptr + offset % CHUNK_SIZE);
208}
209
210#define MON_RING_EMPTY(rp) ((rp)->b_cnt == 0)
211
212static unsigned char xfer_to_pipe[4] = {
213 PIPE_CONTROL, PIPE_ISOCHRONOUS, PIPE_BULK, PIPE_INTERRUPT
214};
215
216static const struct class mon_bin_class = {
217 .name = "usbmon",
218};
219
220static dev_t mon_bin_dev0;
221static struct cdev mon_bin_cdev;
222
223static void mon_buff_area_fill(const struct mon_reader_bin *rp,
224 unsigned int offset, unsigned int size);
225static int mon_bin_wait_event(struct file *file, struct mon_reader_bin *rp);
226static int mon_alloc_buff(struct mon_pgmap *map, int npages);
227static void mon_free_buff(struct mon_pgmap *map, int npages);
228
229/*
230 * This is a "chunked memcpy". It does not manipulate any counters.
231 */
232static unsigned int mon_copy_to_buff(const struct mon_reader_bin *this,
233 unsigned int off, const unsigned char *from, unsigned int length)
234{
235 unsigned int step_len;
236 unsigned char *buf;
237 unsigned int in_page;
238
239 while (length) {
240 /*
241 * Determine step_len.
242 */
243 step_len = length;
244 in_page = CHUNK_SIZE - (off & (CHUNK_SIZE-1));
245 if (in_page < step_len)
246 step_len = in_page;
247
248 /*
249 * Copy data and advance pointers.
250 */
251 buf = this->b_vec[off / CHUNK_SIZE].ptr + off % CHUNK_SIZE;
252 memcpy(buf, from, step_len);
253 if ((off += step_len) >= this->b_size) off = 0;
254 from += step_len;
255 length -= step_len;
256 }
257 return off;
258}
259
260/*
261 * This is a little worse than the above because it's "chunked copy_to_user".
262 * The return value is an error code, not an offset.
263 */
264static int copy_from_buf(const struct mon_reader_bin *this, unsigned int off,
265 char __user *to, int length)
266{
267 unsigned int step_len;
268 unsigned char *buf;
269 unsigned int in_page;
270
271 while (length) {
272 /*
273 * Determine step_len.
274 */
275 step_len = length;
276 in_page = CHUNK_SIZE - (off & (CHUNK_SIZE-1));
277 if (in_page < step_len)
278 step_len = in_page;
279
280 /*
281 * Copy data and advance pointers.
282 */
283 buf = this->b_vec[off / CHUNK_SIZE].ptr + off % CHUNK_SIZE;
284 if (copy_to_user(to, buf, step_len))
285 return -EINVAL;
286 if ((off += step_len) >= this->b_size) off = 0;
287 to += step_len;
288 length -= step_len;
289 }
290 return 0;
291}
292
293/*
294 * Allocate an (aligned) area in the buffer.
295 * This is called under b_lock.
296 * Returns ~0 on failure.
297 */
298static unsigned int mon_buff_area_alloc(struct mon_reader_bin *rp,
299 unsigned int size)
300{
301 unsigned int offset;
302
303 size = (size + PKT_ALIGN-1) & ~(PKT_ALIGN-1);
304 if (rp->b_cnt + size > rp->b_size)
305 return ~0;
306 offset = rp->b_in;
307 rp->b_cnt += size;
308 if ((rp->b_in += size) >= rp->b_size)
309 rp->b_in -= rp->b_size;
310 return offset;
311}
312
313/*
314 * This is the same thing as mon_buff_area_alloc, only it does not allow
315 * buffers to wrap. This is needed by applications which pass references
316 * into mmap-ed buffers up their stacks (libpcap can do that).
317 *
318 * Currently, we always have the header stuck with the data, although
319 * it is not strictly speaking necessary.
320 *
321 * When a buffer would wrap, we place a filler packet to mark the space.
322 */
323static unsigned int mon_buff_area_alloc_contiguous(struct mon_reader_bin *rp,
324 unsigned int size)
325{
326 unsigned int offset;
327 unsigned int fill_size;
328
329 size = (size + PKT_ALIGN-1) & ~(PKT_ALIGN-1);
330 if (rp->b_cnt + size > rp->b_size)
331 return ~0;
332 if (rp->b_in + size > rp->b_size) {
333 /*
334 * This would wrap. Find if we still have space after
335 * skipping to the end of the buffer. If we do, place
336 * a filler packet and allocate a new packet.
337 */
338 fill_size = rp->b_size - rp->b_in;
339 if (rp->b_cnt + size + fill_size > rp->b_size)
340 return ~0;
341 mon_buff_area_fill(rp, rp->b_in, fill_size);
342
343 offset = 0;
344 rp->b_in = size;
345 rp->b_cnt += size + fill_size;
346 } else if (rp->b_in + size == rp->b_size) {
347 offset = rp->b_in;
348 rp->b_in = 0;
349 rp->b_cnt += size;
350 } else {
351 offset = rp->b_in;
352 rp->b_in += size;
353 rp->b_cnt += size;
354 }
355 return offset;
356}
357
358/*
359 * Return a few (kilo-)bytes to the head of the buffer.
360 * This is used if a data fetch fails.
361 */
362static void mon_buff_area_shrink(struct mon_reader_bin *rp, unsigned int size)
363{
364
365 /* size &= ~(PKT_ALIGN-1); -- we're called with aligned size */
366 rp->b_cnt -= size;
367 if (rp->b_in < size)
368 rp->b_in += rp->b_size;
369 rp->b_in -= size;
370}
371
372/*
373 * This has to be called under both b_lock and fetch_lock, because
374 * it accesses both b_cnt and b_out.
375 */
376static void mon_buff_area_free(struct mon_reader_bin *rp, unsigned int size)
377{
378
379 size = (size + PKT_ALIGN-1) & ~(PKT_ALIGN-1);
380 rp->b_cnt -= size;
381 if ((rp->b_out += size) >= rp->b_size)
382 rp->b_out -= rp->b_size;
383}
384
385static void mon_buff_area_fill(const struct mon_reader_bin *rp,
386 unsigned int offset, unsigned int size)
387{
388 struct mon_bin_hdr *ep;
389
390 ep = MON_OFF2HDR(rp, offset);
391 memset(ep, 0, PKT_SIZE);
392 ep->type = '@';
393 ep->len_cap = size - PKT_SIZE;
394}
395
396static inline char mon_bin_get_setup(unsigned char *setupb,
397 const struct urb *urb, char ev_type)
398{
399
400 if (urb->setup_packet == NULL)
401 return 'Z';
402 memcpy(setupb, urb->setup_packet, SETUP_LEN);
403 return 0;
404}
405
406static unsigned int mon_bin_get_data(const struct mon_reader_bin *rp,
407 unsigned int offset, struct urb *urb, unsigned int length,
408 char *flag)
409{
410 int i;
411 struct scatterlist *sg;
412 unsigned int this_len;
413
414 *flag = 0;
415 if (urb->num_sgs == 0) {
416 if (urb->transfer_buffer == NULL) {
417 *flag = 'Z';
418 return length;
419 }
420 mon_copy_to_buff(rp, offset, urb->transfer_buffer, length);
421 length = 0;
422
423 } else {
424 /* If IOMMU coalescing occurred, we cannot trust sg_page */
425 if (urb->transfer_flags & URB_DMA_SG_COMBINED) {
426 *flag = 'D';
427 return length;
428 }
429
430 /* Copy up to the first non-addressable segment */
431 for_each_sg(urb->sg, sg, urb->num_sgs, i) {
432 if (length == 0 || PageHighMem(sg_page(sg)))
433 break;
434 this_len = min_t(unsigned int, sg->length, length);
435 offset = mon_copy_to_buff(rp, offset, sg_virt(sg),
436 this_len);
437 length -= this_len;
438 }
439 if (i == 0)
440 *flag = 'D';
441 }
442
443 return length;
444}
445
446/*
447 * This is the look-ahead pass in case of 'C Zi', when actual_length cannot
448 * be used to determine the length of the whole contiguous buffer.
449 */
450static unsigned int mon_bin_collate_isodesc(const struct mon_reader_bin *rp,
451 struct urb *urb, unsigned int ndesc)
452{
453 struct usb_iso_packet_descriptor *fp;
454 unsigned int length;
455
456 length = 0;
457 fp = urb->iso_frame_desc;
458 while (ndesc-- != 0) {
459 if (fp->actual_length != 0) {
460 if (fp->offset + fp->actual_length > length)
461 length = fp->offset + fp->actual_length;
462 }
463 fp++;
464 }
465 return length;
466}
467
468static void mon_bin_get_isodesc(const struct mon_reader_bin *rp,
469 unsigned int offset, struct urb *urb, char ev_type, unsigned int ndesc)
470{
471 struct mon_bin_isodesc *dp;
472 struct usb_iso_packet_descriptor *fp;
473
474 fp = urb->iso_frame_desc;
475 while (ndesc-- != 0) {
476 dp = (struct mon_bin_isodesc *)
477 (rp->b_vec[offset / CHUNK_SIZE].ptr + offset % CHUNK_SIZE);
478 dp->iso_status = fp->status;
479 dp->iso_off = fp->offset;
480 dp->iso_len = (ev_type == 'S') ? fp->length : fp->actual_length;
481 dp->_pad = 0;
482 if ((offset += sizeof(struct mon_bin_isodesc)) >= rp->b_size)
483 offset = 0;
484 fp++;
485 }
486}
487
488static void mon_bin_event(struct mon_reader_bin *rp, struct urb *urb,
489 char ev_type, int status)
490{
491 const struct usb_endpoint_descriptor *epd = &urb->ep->desc;
492 struct timespec64 ts;
493 unsigned long flags;
494 unsigned int urb_length;
495 unsigned int offset;
496 unsigned int length;
497 unsigned int delta;
498 unsigned int ndesc, lendesc;
499 unsigned char dir;
500 struct mon_bin_hdr *ep;
501 char data_tag = 0;
502
503 ktime_get_real_ts64(&ts);
504
505 spin_lock_irqsave(&rp->b_lock, flags);
506
507 /*
508 * Find the maximum allowable length, then allocate space.
509 */
510 urb_length = (ev_type == 'S') ?
511 urb->transfer_buffer_length : urb->actual_length;
512 length = urb_length;
513
514 if (usb_endpoint_xfer_isoc(epd)) {
515 if (urb->number_of_packets < 0) {
516 ndesc = 0;
517 } else if (urb->number_of_packets >= ISODESC_MAX) {
518 ndesc = ISODESC_MAX;
519 } else {
520 ndesc = urb->number_of_packets;
521 }
522 if (ev_type == 'C' && usb_urb_dir_in(urb))
523 length = mon_bin_collate_isodesc(rp, urb, ndesc);
524 } else {
525 ndesc = 0;
526 }
527 lendesc = ndesc*sizeof(struct mon_bin_isodesc);
528
529 /* not an issue unless there's a subtle bug in a HCD somewhere */
530 if (length >= urb->transfer_buffer_length)
531 length = urb->transfer_buffer_length;
532
533 if (length >= rp->b_size/5)
534 length = rp->b_size/5;
535
536 if (usb_urb_dir_in(urb)) {
537 if (ev_type == 'S') {
538 length = 0;
539 data_tag = '<';
540 }
541 /* Cannot rely on endpoint number in case of control ep.0 */
542 dir = USB_DIR_IN;
543 } else {
544 if (ev_type == 'C') {
545 length = 0;
546 data_tag = '>';
547 }
548 dir = 0;
549 }
550
551 if (rp->mmap_active) {
552 offset = mon_buff_area_alloc_contiguous(rp,
553 length + PKT_SIZE + lendesc);
554 } else {
555 offset = mon_buff_area_alloc(rp, length + PKT_SIZE + lendesc);
556 }
557 if (offset == ~0) {
558 rp->cnt_lost++;
559 spin_unlock_irqrestore(&rp->b_lock, flags);
560 return;
561 }
562
563 ep = MON_OFF2HDR(rp, offset);
564 if ((offset += PKT_SIZE) >= rp->b_size) offset = 0;
565
566 /*
567 * Fill the allocated area.
568 */
569 memset(ep, 0, PKT_SIZE);
570 ep->type = ev_type;
571 ep->xfer_type = xfer_to_pipe[usb_endpoint_type(epd)];
572 ep->epnum = dir | usb_endpoint_num(epd);
573 ep->devnum = urb->dev->devnum;
574 ep->busnum = urb->dev->bus->busnum;
575 ep->id = (unsigned long) urb;
576 ep->ts_sec = ts.tv_sec;
577 ep->ts_usec = ts.tv_nsec / NSEC_PER_USEC;
578 ep->status = status;
579 ep->len_urb = urb_length;
580 ep->len_cap = length + lendesc;
581 ep->xfer_flags = urb->transfer_flags;
582
583 if (usb_endpoint_xfer_int(epd)) {
584 ep->interval = urb->interval;
585 } else if (usb_endpoint_xfer_isoc(epd)) {
586 ep->interval = urb->interval;
587 ep->start_frame = urb->start_frame;
588 ep->s.iso.error_count = urb->error_count;
589 ep->s.iso.numdesc = urb->number_of_packets;
590 }
591
592 if (usb_endpoint_xfer_control(epd) && ev_type == 'S') {
593 ep->flag_setup = mon_bin_get_setup(ep->s.setup, urb, ev_type);
594 } else {
595 ep->flag_setup = '-';
596 }
597
598 if (ndesc != 0) {
599 ep->ndesc = ndesc;
600 mon_bin_get_isodesc(rp, offset, urb, ev_type, ndesc);
601 if ((offset += lendesc) >= rp->b_size)
602 offset -= rp->b_size;
603 }
604
605 if (length != 0) {
606 length = mon_bin_get_data(rp, offset, urb, length,
607 &ep->flag_data);
608 if (length > 0) {
609 delta = (ep->len_cap + PKT_ALIGN-1) & ~(PKT_ALIGN-1);
610 ep->len_cap -= length;
611 delta -= (ep->len_cap + PKT_ALIGN-1) & ~(PKT_ALIGN-1);
612 mon_buff_area_shrink(rp, delta);
613 }
614 } else {
615 ep->flag_data = data_tag;
616 }
617
618 spin_unlock_irqrestore(&rp->b_lock, flags);
619
620 wake_up(&rp->b_wait);
621}
622
623static void mon_bin_submit(void *data, struct urb *urb)
624{
625 struct mon_reader_bin *rp = data;
626 mon_bin_event(rp, urb, 'S', -EINPROGRESS);
627}
628
629static void mon_bin_complete(void *data, struct urb *urb, int status)
630{
631 struct mon_reader_bin *rp = data;
632 mon_bin_event(rp, urb, 'C', status);
633}
634
635static void mon_bin_error(void *data, struct urb *urb, int error)
636{
637 struct mon_reader_bin *rp = data;
638 struct timespec64 ts;
639 unsigned long flags;
640 unsigned int offset;
641 struct mon_bin_hdr *ep;
642
643 ktime_get_real_ts64(&ts);
644
645 spin_lock_irqsave(&rp->b_lock, flags);
646
647 offset = mon_buff_area_alloc(rp, PKT_SIZE);
648 if (offset == ~0) {
649 /* Not incrementing cnt_lost. Just because. */
650 spin_unlock_irqrestore(&rp->b_lock, flags);
651 return;
652 }
653
654 ep = MON_OFF2HDR(rp, offset);
655
656 memset(ep, 0, PKT_SIZE);
657 ep->type = 'E';
658 ep->xfer_type = xfer_to_pipe[usb_endpoint_type(&urb->ep->desc)];
659 ep->epnum = usb_urb_dir_in(urb) ? USB_DIR_IN : 0;
660 ep->epnum |= usb_endpoint_num(&urb->ep->desc);
661 ep->devnum = urb->dev->devnum;
662 ep->busnum = urb->dev->bus->busnum;
663 ep->id = (unsigned long) urb;
664 ep->ts_sec = ts.tv_sec;
665 ep->ts_usec = ts.tv_nsec / NSEC_PER_USEC;
666 ep->status = error;
667
668 ep->flag_setup = '-';
669 ep->flag_data = 'E';
670
671 spin_unlock_irqrestore(&rp->b_lock, flags);
672
673 wake_up(&rp->b_wait);
674}
675
676static int mon_bin_open(struct inode *inode, struct file *file)
677{
678 struct mon_bus *mbus;
679 struct mon_reader_bin *rp;
680 size_t size;
681 int rc;
682
683 mutex_lock(&mon_lock);
684 mbus = mon_bus_lookup(iminor(inode));
685 if (mbus == NULL) {
686 mutex_unlock(&mon_lock);
687 return -ENODEV;
688 }
689 if (mbus != &mon_bus0 && mbus->u_bus == NULL) {
690 printk(KERN_ERR TAG ": consistency error on open\n");
691 mutex_unlock(&mon_lock);
692 return -ENODEV;
693 }
694
695 rp = kzalloc(sizeof(struct mon_reader_bin), GFP_KERNEL);
696 if (rp == NULL) {
697 rc = -ENOMEM;
698 goto err_alloc;
699 }
700 spin_lock_init(&rp->b_lock);
701 init_waitqueue_head(&rp->b_wait);
702 mutex_init(&rp->fetch_lock);
703 rp->b_size = BUFF_DFL;
704
705 size = sizeof(struct mon_pgmap) * (rp->b_size/CHUNK_SIZE);
706 if ((rp->b_vec = kzalloc(size, GFP_KERNEL)) == NULL) {
707 rc = -ENOMEM;
708 goto err_allocvec;
709 }
710
711 if ((rc = mon_alloc_buff(rp->b_vec, rp->b_size/CHUNK_SIZE)) < 0)
712 goto err_allocbuff;
713
714 rp->r.m_bus = mbus;
715 rp->r.r_data = rp;
716 rp->r.rnf_submit = mon_bin_submit;
717 rp->r.rnf_error = mon_bin_error;
718 rp->r.rnf_complete = mon_bin_complete;
719
720 mon_reader_add(mbus, &rp->r);
721
722 file->private_data = rp;
723 mutex_unlock(&mon_lock);
724 return 0;
725
726err_allocbuff:
727 kfree(rp->b_vec);
728err_allocvec:
729 kfree(rp);
730err_alloc:
731 mutex_unlock(&mon_lock);
732 return rc;
733}
734
735/*
736 * Extract an event from buffer and copy it to user space.
737 * Wait if there is no event ready.
738 * Returns zero or error.
739 */
740static int mon_bin_get_event(struct file *file, struct mon_reader_bin *rp,
741 struct mon_bin_hdr __user *hdr, unsigned int hdrbytes,
742 void __user *data, unsigned int nbytes)
743{
744 unsigned long flags;
745 struct mon_bin_hdr *ep;
746 size_t step_len;
747 unsigned int offset;
748 int rc;
749
750 mutex_lock(&rp->fetch_lock);
751
752 if ((rc = mon_bin_wait_event(file, rp)) < 0) {
753 mutex_unlock(&rp->fetch_lock);
754 return rc;
755 }
756
757 ep = MON_OFF2HDR(rp, rp->b_out);
758
759 if (copy_to_user(hdr, ep, hdrbytes)) {
760 mutex_unlock(&rp->fetch_lock);
761 return -EFAULT;
762 }
763
764 step_len = min(ep->len_cap, nbytes);
765 if ((offset = rp->b_out + PKT_SIZE) >= rp->b_size) offset = 0;
766
767 if (copy_from_buf(rp, offset, data, step_len)) {
768 mutex_unlock(&rp->fetch_lock);
769 return -EFAULT;
770 }
771
772 spin_lock_irqsave(&rp->b_lock, flags);
773 mon_buff_area_free(rp, PKT_SIZE + ep->len_cap);
774 spin_unlock_irqrestore(&rp->b_lock, flags);
775 rp->b_read = 0;
776
777 mutex_unlock(&rp->fetch_lock);
778 return 0;
779}
780
781static int mon_bin_release(struct inode *inode, struct file *file)
782{
783 struct mon_reader_bin *rp = file->private_data;
784 struct mon_bus* mbus = rp->r.m_bus;
785
786 mutex_lock(&mon_lock);
787
788 if (mbus->nreaders <= 0) {
789 printk(KERN_ERR TAG ": consistency error on close\n");
790 mutex_unlock(&mon_lock);
791 return 0;
792 }
793 mon_reader_del(mbus, &rp->r);
794
795 mon_free_buff(rp->b_vec, rp->b_size/CHUNK_SIZE);
796 kfree(rp->b_vec);
797 kfree(rp);
798
799 mutex_unlock(&mon_lock);
800 return 0;
801}
802
803static ssize_t mon_bin_read(struct file *file, char __user *buf,
804 size_t nbytes, loff_t *ppos)
805{
806 struct mon_reader_bin *rp = file->private_data;
807 unsigned int hdrbytes = PKT_SZ_API0;
808 unsigned long flags;
809 struct mon_bin_hdr *ep;
810 unsigned int offset;
811 size_t step_len;
812 char *ptr;
813 ssize_t done = 0;
814 int rc;
815
816 mutex_lock(&rp->fetch_lock);
817
818 if ((rc = mon_bin_wait_event(file, rp)) < 0) {
819 mutex_unlock(&rp->fetch_lock);
820 return rc;
821 }
822
823 ep = MON_OFF2HDR(rp, rp->b_out);
824
825 if (rp->b_read < hdrbytes) {
826 step_len = min_t(size_t, nbytes, hdrbytes - rp->b_read);
827 ptr = ((char *)ep) + rp->b_read;
828 if (step_len && copy_to_user(buf, ptr, step_len)) {
829 mutex_unlock(&rp->fetch_lock);
830 return -EFAULT;
831 }
832 nbytes -= step_len;
833 buf += step_len;
834 rp->b_read += step_len;
835 done += step_len;
836 }
837
838 if (rp->b_read >= hdrbytes) {
839 step_len = ep->len_cap;
840 step_len -= rp->b_read - hdrbytes;
841 if (step_len > nbytes)
842 step_len = nbytes;
843 offset = rp->b_out + PKT_SIZE;
844 offset += rp->b_read - hdrbytes;
845 if (offset >= rp->b_size)
846 offset -= rp->b_size;
847 if (copy_from_buf(rp, offset, buf, step_len)) {
848 mutex_unlock(&rp->fetch_lock);
849 return -EFAULT;
850 }
851 nbytes -= step_len;
852 buf += step_len;
853 rp->b_read += step_len;
854 done += step_len;
855 }
856
857 /*
858 * Check if whole packet was read, and if so, jump to the next one.
859 */
860 if (rp->b_read >= hdrbytes + ep->len_cap) {
861 spin_lock_irqsave(&rp->b_lock, flags);
862 mon_buff_area_free(rp, PKT_SIZE + ep->len_cap);
863 spin_unlock_irqrestore(&rp->b_lock, flags);
864 rp->b_read = 0;
865 }
866
867 mutex_unlock(&rp->fetch_lock);
868 return done;
869}
870
871/*
872 * Remove at most nevents from chunked buffer.
873 * Returns the number of removed events.
874 */
875static int mon_bin_flush(struct mon_reader_bin *rp, unsigned nevents)
876{
877 unsigned long flags;
878 struct mon_bin_hdr *ep;
879 int i;
880
881 mutex_lock(&rp->fetch_lock);
882 spin_lock_irqsave(&rp->b_lock, flags);
883 for (i = 0; i < nevents; ++i) {
884 if (MON_RING_EMPTY(rp))
885 break;
886
887 ep = MON_OFF2HDR(rp, rp->b_out);
888 mon_buff_area_free(rp, PKT_SIZE + ep->len_cap);
889 }
890 spin_unlock_irqrestore(&rp->b_lock, flags);
891 rp->b_read = 0;
892 mutex_unlock(&rp->fetch_lock);
893 return i;
894}
895
896/*
897 * Fetch at most max event offsets into the buffer and put them into vec.
898 * The events are usually freed later with mon_bin_flush.
899 * Return the effective number of events fetched.
900 */
901static int mon_bin_fetch(struct file *file, struct mon_reader_bin *rp,
902 u32 __user *vec, unsigned int max)
903{
904 unsigned int cur_out;
905 unsigned int bytes, avail;
906 unsigned int size;
907 unsigned int nevents;
908 struct mon_bin_hdr *ep;
909 unsigned long flags;
910 int rc;
911
912 mutex_lock(&rp->fetch_lock);
913
914 if ((rc = mon_bin_wait_event(file, rp)) < 0) {
915 mutex_unlock(&rp->fetch_lock);
916 return rc;
917 }
918
919 spin_lock_irqsave(&rp->b_lock, flags);
920 avail = rp->b_cnt;
921 spin_unlock_irqrestore(&rp->b_lock, flags);
922
923 cur_out = rp->b_out;
924 nevents = 0;
925 bytes = 0;
926 while (bytes < avail) {
927 if (nevents >= max)
928 break;
929
930 ep = MON_OFF2HDR(rp, cur_out);
931 if (put_user(cur_out, &vec[nevents])) {
932 mutex_unlock(&rp->fetch_lock);
933 return -EFAULT;
934 }
935
936 nevents++;
937 size = ep->len_cap + PKT_SIZE;
938 size = (size + PKT_ALIGN-1) & ~(PKT_ALIGN-1);
939 if ((cur_out += size) >= rp->b_size)
940 cur_out -= rp->b_size;
941 bytes += size;
942 }
943
944 mutex_unlock(&rp->fetch_lock);
945 return nevents;
946}
947
948/*
949 * Count events. This is almost the same as the above mon_bin_fetch,
950 * only we do not store offsets into user vector, and we have no limit.
951 */
952static int mon_bin_queued(struct mon_reader_bin *rp)
953{
954 unsigned int cur_out;
955 unsigned int bytes, avail;
956 unsigned int size;
957 unsigned int nevents;
958 struct mon_bin_hdr *ep;
959 unsigned long flags;
960
961 mutex_lock(&rp->fetch_lock);
962
963 spin_lock_irqsave(&rp->b_lock, flags);
964 avail = rp->b_cnt;
965 spin_unlock_irqrestore(&rp->b_lock, flags);
966
967 cur_out = rp->b_out;
968 nevents = 0;
969 bytes = 0;
970 while (bytes < avail) {
971 ep = MON_OFF2HDR(rp, cur_out);
972
973 nevents++;
974 size = ep->len_cap + PKT_SIZE;
975 size = (size + PKT_ALIGN-1) & ~(PKT_ALIGN-1);
976 if ((cur_out += size) >= rp->b_size)
977 cur_out -= rp->b_size;
978 bytes += size;
979 }
980
981 mutex_unlock(&rp->fetch_lock);
982 return nevents;
983}
984
985/*
986 */
987static long mon_bin_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
988{
989 struct mon_reader_bin *rp = file->private_data;
990 // struct mon_bus* mbus = rp->r.m_bus;
991 int ret = 0;
992 struct mon_bin_hdr *ep;
993 unsigned long flags;
994
995 switch (cmd) {
996
997 case MON_IOCQ_URB_LEN:
998 /*
999 * N.B. This only returns the size of data, without the header.
1000 */
1001 spin_lock_irqsave(&rp->b_lock, flags);
1002 if (!MON_RING_EMPTY(rp)) {
1003 ep = MON_OFF2HDR(rp, rp->b_out);
1004 ret = ep->len_cap;
1005 }
1006 spin_unlock_irqrestore(&rp->b_lock, flags);
1007 break;
1008
1009 case MON_IOCQ_RING_SIZE:
1010 mutex_lock(&rp->fetch_lock);
1011 ret = rp->b_size;
1012 mutex_unlock(&rp->fetch_lock);
1013 break;
1014
1015 case MON_IOCT_RING_SIZE:
1016 /*
1017 * Changing the buffer size will flush it's contents; the new
1018 * buffer is allocated before releasing the old one to be sure
1019 * the device will stay functional also in case of memory
1020 * pressure.
1021 */
1022 {
1023 int size;
1024 struct mon_pgmap *vec;
1025
1026 if (arg < BUFF_MIN || arg > BUFF_MAX)
1027 return -EINVAL;
1028
1029 size = CHUNK_ALIGN(arg);
1030 vec = kcalloc(size / CHUNK_SIZE, sizeof(struct mon_pgmap),
1031 GFP_KERNEL);
1032 if (vec == NULL) {
1033 ret = -ENOMEM;
1034 break;
1035 }
1036
1037 ret = mon_alloc_buff(vec, size/CHUNK_SIZE);
1038 if (ret < 0) {
1039 kfree(vec);
1040 break;
1041 }
1042
1043 mutex_lock(&rp->fetch_lock);
1044 spin_lock_irqsave(&rp->b_lock, flags);
1045 if (rp->mmap_active) {
1046 mon_free_buff(vec, size/CHUNK_SIZE);
1047 kfree(vec);
1048 ret = -EBUSY;
1049 } else {
1050 mon_free_buff(rp->b_vec, rp->b_size/CHUNK_SIZE);
1051 kfree(rp->b_vec);
1052 rp->b_vec = vec;
1053 rp->b_size = size;
1054 rp->b_read = rp->b_in = rp->b_out = rp->b_cnt = 0;
1055 rp->cnt_lost = 0;
1056 }
1057 spin_unlock_irqrestore(&rp->b_lock, flags);
1058 mutex_unlock(&rp->fetch_lock);
1059 }
1060 break;
1061
1062 case MON_IOCH_MFLUSH:
1063 ret = mon_bin_flush(rp, arg);
1064 break;
1065
1066 case MON_IOCX_GET:
1067 case MON_IOCX_GETX:
1068 {
1069 struct mon_bin_get getb;
1070
1071 if (copy_from_user(&getb, (void __user *)arg,
1072 sizeof(struct mon_bin_get)))
1073 return -EFAULT;
1074
1075 if (getb.alloc > 0x10000000) /* Want to cast to u32 */
1076 return -EINVAL;
1077 ret = mon_bin_get_event(file, rp, getb.hdr,
1078 (cmd == MON_IOCX_GET)? PKT_SZ_API0: PKT_SZ_API1,
1079 getb.data, (unsigned int)getb.alloc);
1080 }
1081 break;
1082
1083 case MON_IOCX_MFETCH:
1084 {
1085 struct mon_bin_mfetch mfetch;
1086 struct mon_bin_mfetch __user *uptr;
1087
1088 uptr = (struct mon_bin_mfetch __user *)arg;
1089
1090 if (copy_from_user(&mfetch, uptr, sizeof(mfetch)))
1091 return -EFAULT;
1092
1093 if (mfetch.nflush) {
1094 ret = mon_bin_flush(rp, mfetch.nflush);
1095 if (ret < 0)
1096 return ret;
1097 if (put_user(ret, &uptr->nflush))
1098 return -EFAULT;
1099 }
1100 ret = mon_bin_fetch(file, rp, mfetch.offvec, mfetch.nfetch);
1101 if (ret < 0)
1102 return ret;
1103 if (put_user(ret, &uptr->nfetch))
1104 return -EFAULT;
1105 ret = 0;
1106 }
1107 break;
1108
1109 case MON_IOCG_STATS: {
1110 struct mon_bin_stats __user *sp;
1111 unsigned int nevents;
1112 unsigned int ndropped;
1113
1114 spin_lock_irqsave(&rp->b_lock, flags);
1115 ndropped = rp->cnt_lost;
1116 rp->cnt_lost = 0;
1117 spin_unlock_irqrestore(&rp->b_lock, flags);
1118 nevents = mon_bin_queued(rp);
1119
1120 sp = (struct mon_bin_stats __user *)arg;
1121 if (put_user(ndropped, &sp->dropped))
1122 return -EFAULT;
1123 if (put_user(nevents, &sp->queued))
1124 return -EFAULT;
1125
1126 }
1127 break;
1128
1129 default:
1130 return -ENOTTY;
1131 }
1132
1133 return ret;
1134}
1135
1136#ifdef CONFIG_COMPAT
1137static long mon_bin_compat_ioctl(struct file *file,
1138 unsigned int cmd, unsigned long arg)
1139{
1140 struct mon_reader_bin *rp = file->private_data;
1141 int ret;
1142
1143 switch (cmd) {
1144
1145 case MON_IOCX_GET32:
1146 case MON_IOCX_GETX32:
1147 {
1148 struct mon_bin_get32 getb;
1149
1150 if (copy_from_user(&getb, (void __user *)arg,
1151 sizeof(struct mon_bin_get32)))
1152 return -EFAULT;
1153
1154 ret = mon_bin_get_event(file, rp, compat_ptr(getb.hdr32),
1155 (cmd == MON_IOCX_GET32)? PKT_SZ_API0: PKT_SZ_API1,
1156 compat_ptr(getb.data32), getb.alloc32);
1157 if (ret < 0)
1158 return ret;
1159 }
1160 return 0;
1161
1162 case MON_IOCX_MFETCH32:
1163 {
1164 struct mon_bin_mfetch32 mfetch;
1165 struct mon_bin_mfetch32 __user *uptr;
1166
1167 uptr = (struct mon_bin_mfetch32 __user *) compat_ptr(arg);
1168
1169 if (copy_from_user(&mfetch, uptr, sizeof(mfetch)))
1170 return -EFAULT;
1171
1172 if (mfetch.nflush32) {
1173 ret = mon_bin_flush(rp, mfetch.nflush32);
1174 if (ret < 0)
1175 return ret;
1176 if (put_user(ret, &uptr->nflush32))
1177 return -EFAULT;
1178 }
1179 ret = mon_bin_fetch(file, rp, compat_ptr(mfetch.offvec32),
1180 mfetch.nfetch32);
1181 if (ret < 0)
1182 return ret;
1183 if (put_user(ret, &uptr->nfetch32))
1184 return -EFAULT;
1185 }
1186 return 0;
1187
1188 case MON_IOCG_STATS:
1189 return mon_bin_ioctl(file, cmd, (unsigned long) compat_ptr(arg));
1190
1191 case MON_IOCQ_URB_LEN:
1192 case MON_IOCQ_RING_SIZE:
1193 case MON_IOCT_RING_SIZE:
1194 case MON_IOCH_MFLUSH:
1195 return mon_bin_ioctl(file, cmd, arg);
1196
1197 default:
1198 ;
1199 }
1200 return -ENOTTY;
1201}
1202#endif /* CONFIG_COMPAT */
1203
1204static __poll_t
1205mon_bin_poll(struct file *file, struct poll_table_struct *wait)
1206{
1207 struct mon_reader_bin *rp = file->private_data;
1208 __poll_t mask = 0;
1209 unsigned long flags;
1210
1211 if (file->f_mode & FMODE_READ)
1212 poll_wait(file, &rp->b_wait, wait);
1213
1214 spin_lock_irqsave(&rp->b_lock, flags);
1215 if (!MON_RING_EMPTY(rp))
1216 mask |= EPOLLIN | EPOLLRDNORM; /* readable */
1217 spin_unlock_irqrestore(&rp->b_lock, flags);
1218 return mask;
1219}
1220
1221/*
1222 * open and close: just keep track of how many times the device is
1223 * mapped, to use the proper memory allocation function.
1224 */
1225static void mon_bin_vma_open(struct vm_area_struct *vma)
1226{
1227 struct mon_reader_bin *rp = vma->vm_private_data;
1228 unsigned long flags;
1229
1230 spin_lock_irqsave(&rp->b_lock, flags);
1231 rp->mmap_active++;
1232 spin_unlock_irqrestore(&rp->b_lock, flags);
1233}
1234
1235static void mon_bin_vma_close(struct vm_area_struct *vma)
1236{
1237 unsigned long flags;
1238
1239 struct mon_reader_bin *rp = vma->vm_private_data;
1240 spin_lock_irqsave(&rp->b_lock, flags);
1241 rp->mmap_active--;
1242 spin_unlock_irqrestore(&rp->b_lock, flags);
1243}
1244
1245/*
1246 * Map ring pages to user space.
1247 */
1248static vm_fault_t mon_bin_vma_fault(struct vm_fault *vmf)
1249{
1250 struct mon_reader_bin *rp = vmf->vma->vm_private_data;
1251 unsigned long offset, chunk_idx;
1252 struct page *pageptr;
1253 unsigned long flags;
1254
1255 spin_lock_irqsave(&rp->b_lock, flags);
1256 offset = vmf->pgoff << PAGE_SHIFT;
1257 if (offset >= rp->b_size) {
1258 spin_unlock_irqrestore(&rp->b_lock, flags);
1259 return VM_FAULT_SIGBUS;
1260 }
1261 chunk_idx = offset / CHUNK_SIZE;
1262 pageptr = rp->b_vec[chunk_idx].pg;
1263 get_page(pageptr);
1264 vmf->page = pageptr;
1265 spin_unlock_irqrestore(&rp->b_lock, flags);
1266 return 0;
1267}
1268
1269static const struct vm_operations_struct mon_bin_vm_ops = {
1270 .open = mon_bin_vma_open,
1271 .close = mon_bin_vma_close,
1272 .fault = mon_bin_vma_fault,
1273};
1274
1275static int mon_bin_mmap(struct file *filp, struct vm_area_struct *vma)
1276{
1277 /* don't do anything here: "fault" will set up page table entries */
1278 vma->vm_ops = &mon_bin_vm_ops;
1279
1280 if (vma->vm_flags & VM_WRITE)
1281 return -EPERM;
1282
1283 vm_flags_mod(vma, VM_DONTEXPAND | VM_DONTDUMP, VM_MAYWRITE);
1284 vma->vm_private_data = filp->private_data;
1285 mon_bin_vma_open(vma);
1286 return 0;
1287}
1288
1289static const struct file_operations mon_fops_binary = {
1290 .owner = THIS_MODULE,
1291 .open = mon_bin_open,
1292 .read = mon_bin_read,
1293 /* .write = mon_text_write, */
1294 .poll = mon_bin_poll,
1295 .unlocked_ioctl = mon_bin_ioctl,
1296#ifdef CONFIG_COMPAT
1297 .compat_ioctl = mon_bin_compat_ioctl,
1298#endif
1299 .release = mon_bin_release,
1300 .mmap = mon_bin_mmap,
1301};
1302
1303static int mon_bin_wait_event(struct file *file, struct mon_reader_bin *rp)
1304{
1305 DECLARE_WAITQUEUE(waita, current);
1306 unsigned long flags;
1307
1308 add_wait_queue(&rp->b_wait, &waita);
1309 set_current_state(TASK_INTERRUPTIBLE);
1310
1311 spin_lock_irqsave(&rp->b_lock, flags);
1312 while (MON_RING_EMPTY(rp)) {
1313 spin_unlock_irqrestore(&rp->b_lock, flags);
1314
1315 if (file->f_flags & O_NONBLOCK) {
1316 set_current_state(TASK_RUNNING);
1317 remove_wait_queue(&rp->b_wait, &waita);
1318 return -EWOULDBLOCK; /* Same as EAGAIN in Linux */
1319 }
1320 schedule();
1321 if (signal_pending(current)) {
1322 remove_wait_queue(&rp->b_wait, &waita);
1323 return -EINTR;
1324 }
1325 set_current_state(TASK_INTERRUPTIBLE);
1326
1327 spin_lock_irqsave(&rp->b_lock, flags);
1328 }
1329 spin_unlock_irqrestore(&rp->b_lock, flags);
1330
1331 set_current_state(TASK_RUNNING);
1332 remove_wait_queue(&rp->b_wait, &waita);
1333 return 0;
1334}
1335
1336static int mon_alloc_buff(struct mon_pgmap *map, int npages)
1337{
1338 int n;
1339 unsigned long vaddr;
1340
1341 for (n = 0; n < npages; n++) {
1342 vaddr = get_zeroed_page(GFP_KERNEL);
1343 if (vaddr == 0) {
1344 while (n-- != 0)
1345 free_page((unsigned long) map[n].ptr);
1346 return -ENOMEM;
1347 }
1348 map[n].ptr = (unsigned char *) vaddr;
1349 map[n].pg = virt_to_page((void *) vaddr);
1350 }
1351 return 0;
1352}
1353
1354static void mon_free_buff(struct mon_pgmap *map, int npages)
1355{
1356 int n;
1357
1358 for (n = 0; n < npages; n++)
1359 free_page((unsigned long) map[n].ptr);
1360}
1361
1362int mon_bin_add(struct mon_bus *mbus, const struct usb_bus *ubus)
1363{
1364 struct device *dev;
1365 unsigned minor = ubus? ubus->busnum: 0;
1366
1367 if (minor >= MON_BIN_MAX_MINOR)
1368 return 0;
1369
1370 dev = device_create(&mon_bin_class, ubus ? ubus->controller : NULL,
1371 MKDEV(MAJOR(mon_bin_dev0), minor), NULL,
1372 "usbmon%d", minor);
1373 if (IS_ERR(dev))
1374 return 0;
1375
1376 mbus->classdev = dev;
1377 return 1;
1378}
1379
1380void mon_bin_del(struct mon_bus *mbus)
1381{
1382 device_destroy(&mon_bin_class, mbus->classdev->devt);
1383}
1384
1385int __init mon_bin_init(void)
1386{
1387 int rc;
1388
1389 rc = class_register(&mon_bin_class);
1390 if (rc)
1391 goto err_class;
1392
1393 rc = alloc_chrdev_region(&mon_bin_dev0, 0, MON_BIN_MAX_MINOR, "usbmon");
1394 if (rc < 0)
1395 goto err_dev;
1396
1397 cdev_init(&mon_bin_cdev, &mon_fops_binary);
1398 mon_bin_cdev.owner = THIS_MODULE;
1399
1400 rc = cdev_add(&mon_bin_cdev, mon_bin_dev0, MON_BIN_MAX_MINOR);
1401 if (rc < 0)
1402 goto err_add;
1403
1404 return 0;
1405
1406err_add:
1407 unregister_chrdev_region(mon_bin_dev0, MON_BIN_MAX_MINOR);
1408err_dev:
1409 class_unregister(&mon_bin_class);
1410err_class:
1411 return rc;
1412}
1413
1414void mon_bin_exit(void)
1415{
1416 cdev_del(&mon_bin_cdev);
1417 unregister_chrdev_region(mon_bin_dev0, MON_BIN_MAX_MINOR);
1418 class_unregister(&mon_bin_class);
1419}