drivers/usb/mon/mon

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

DEFINITIONS
