linux/drivers/usb/mon/mon_bin.c
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   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 struct class *mon_bin_class;
 217static dev_t mon_bin_dev0;
 218static struct cdev mon_bin_cdev;
 219
 220static void mon_buff_area_fill(const struct mon_reader_bin *rp,
 221    unsigned int offset, unsigned int size);
 222static int mon_bin_wait_event(struct file *file, struct mon_reader_bin *rp);
 223static int mon_alloc_buff(struct mon_pgmap *map, int npages);
 224static 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 */
 229static 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 */
 261static 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 */
 295static 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 */
 320static 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 */
 359static 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 */
 373static 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
 382static 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
 393static 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
 403static 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 */
 447static 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
 465static 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
 485static 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
 620static 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
 626static 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
 632static 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
 673static 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
 723err_allocbuff:
 724        kfree(rp->b_vec);
 725err_allocvec:
 726        kfree(rp);
 727err_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 */
 737static 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
 778static 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
 800static 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 */
 872static 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 */
 898static 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 */
 949static 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 */
 984static 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                mon_free_buff(rp->b_vec, rp->b_size/CHUNK_SIZE);
1043                kfree(rp->b_vec);
1044                rp->b_vec  = vec;
1045                rp->b_size = size;
1046                rp->b_read = rp->b_in = rp->b_out = rp->b_cnt = 0;
1047                rp->cnt_lost = 0;
1048                spin_unlock_irqrestore(&rp->b_lock, flags);
1049                mutex_unlock(&rp->fetch_lock);
1050                }
1051                break;
1052
1053        case MON_IOCH_MFLUSH:
1054                ret = mon_bin_flush(rp, arg);
1055                break;
1056
1057        case MON_IOCX_GET:
1058        case MON_IOCX_GETX:
1059                {
1060                struct mon_bin_get getb;
1061
1062                if (copy_from_user(&getb, (void __user *)arg,
1063                                            sizeof(struct mon_bin_get)))
1064                        return -EFAULT;
1065
1066                if (getb.alloc > 0x10000000)    /* Want to cast to u32 */
1067                        return -EINVAL;
1068                ret = mon_bin_get_event(file, rp, getb.hdr,
1069                    (cmd == MON_IOCX_GET)? PKT_SZ_API0: PKT_SZ_API1,
1070                    getb.data, (unsigned int)getb.alloc);
1071                }
1072                break;
1073
1074        case MON_IOCX_MFETCH:
1075                {
1076                struct mon_bin_mfetch mfetch;
1077                struct mon_bin_mfetch __user *uptr;
1078
1079                uptr = (struct mon_bin_mfetch __user *)arg;
1080
1081                if (copy_from_user(&mfetch, uptr, sizeof(mfetch)))
1082                        return -EFAULT;
1083
1084                if (mfetch.nflush) {
1085                        ret = mon_bin_flush(rp, mfetch.nflush);
1086                        if (ret < 0)
1087                                return ret;
1088                        if (put_user(ret, &uptr->nflush))
1089                                return -EFAULT;
1090                }
1091                ret = mon_bin_fetch(file, rp, mfetch.offvec, mfetch.nfetch);
1092                if (ret < 0)
1093                        return ret;
1094                if (put_user(ret, &uptr->nfetch))
1095                        return -EFAULT;
1096                ret = 0;
1097                }
1098                break;
1099
1100        case MON_IOCG_STATS: {
1101                struct mon_bin_stats __user *sp;
1102                unsigned int nevents;
1103                unsigned int ndropped;
1104
1105                spin_lock_irqsave(&rp->b_lock, flags);
1106                ndropped = rp->cnt_lost;
1107                rp->cnt_lost = 0;
1108                spin_unlock_irqrestore(&rp->b_lock, flags);
1109                nevents = mon_bin_queued(rp);
1110
1111                sp = (struct mon_bin_stats __user *)arg;
1112                if (put_user(ndropped, &sp->dropped))
1113                        return -EFAULT;
1114                if (put_user(nevents, &sp->queued))
1115                        return -EFAULT;
1116
1117                }
1118                break;
1119
1120        default:
1121                return -ENOTTY;
1122        }
1123
1124        return ret;
1125}
1126
1127#ifdef CONFIG_COMPAT
1128static long mon_bin_compat_ioctl(struct file *file,
1129    unsigned int cmd, unsigned long arg)
1130{
1131        struct mon_reader_bin *rp = file->private_data;
1132        int ret;
1133
1134        switch (cmd) {
1135
1136        case MON_IOCX_GET32:
1137        case MON_IOCX_GETX32:
1138                {
1139                struct mon_bin_get32 getb;
1140
1141                if (copy_from_user(&getb, (void __user *)arg,
1142                                            sizeof(struct mon_bin_get32)))
1143                        return -EFAULT;
1144
1145                ret = mon_bin_get_event(file, rp, compat_ptr(getb.hdr32),
1146                    (cmd == MON_IOCX_GET32)? PKT_SZ_API0: PKT_SZ_API1,
1147                    compat_ptr(getb.data32), getb.alloc32);
1148                if (ret < 0)
1149                        return ret;
1150                }
1151                return 0;
1152
1153        case MON_IOCX_MFETCH32:
1154                {
1155                struct mon_bin_mfetch32 mfetch;
1156                struct mon_bin_mfetch32 __user *uptr;
1157
1158                uptr = (struct mon_bin_mfetch32 __user *) compat_ptr(arg);
1159
1160                if (copy_from_user(&mfetch, uptr, sizeof(mfetch)))
1161                        return -EFAULT;
1162
1163                if (mfetch.nflush32) {
1164                        ret = mon_bin_flush(rp, mfetch.nflush32);
1165                        if (ret < 0)
1166                                return ret;
1167                        if (put_user(ret, &uptr->nflush32))
1168                                return -EFAULT;
1169                }
1170                ret = mon_bin_fetch(file, rp, compat_ptr(mfetch.offvec32),
1171                    mfetch.nfetch32);
1172                if (ret < 0)
1173                        return ret;
1174                if (put_user(ret, &uptr->nfetch32))
1175                        return -EFAULT;
1176                }
1177                return 0;
1178
1179        case MON_IOCG_STATS:
1180                return mon_bin_ioctl(file, cmd, (unsigned long) compat_ptr(arg));
1181
1182        case MON_IOCQ_URB_LEN:
1183        case MON_IOCQ_RING_SIZE:
1184        case MON_IOCT_RING_SIZE:
1185        case MON_IOCH_MFLUSH:
1186                return mon_bin_ioctl(file, cmd, arg);
1187
1188        default:
1189                ;
1190        }
1191        return -ENOTTY;
1192}
1193#endif /* CONFIG_COMPAT */
1194
1195static __poll_t
1196mon_bin_poll(struct file *file, struct poll_table_struct *wait)
1197{
1198        struct mon_reader_bin *rp = file->private_data;
1199        __poll_t mask = 0;
1200        unsigned long flags;
1201
1202        if (file->f_mode & FMODE_READ)
1203                poll_wait(file, &rp->b_wait, wait);
1204
1205        spin_lock_irqsave(&rp->b_lock, flags);
1206        if (!MON_RING_EMPTY(rp))
1207                mask |= EPOLLIN | EPOLLRDNORM;    /* readable */
1208        spin_unlock_irqrestore(&rp->b_lock, flags);
1209        return mask;
1210}
1211
1212/*
1213 * open and close: just keep track of how many times the device is
1214 * mapped, to use the proper memory allocation function.
1215 */
1216static void mon_bin_vma_open(struct vm_area_struct *vma)
1217{
1218        struct mon_reader_bin *rp = vma->vm_private_data;
1219        rp->mmap_active++;
1220}
1221
1222static void mon_bin_vma_close(struct vm_area_struct *vma)
1223{
1224        struct mon_reader_bin *rp = vma->vm_private_data;
1225        rp->mmap_active--;
1226}
1227
1228/*
1229 * Map ring pages to user space.
1230 */
1231static vm_fault_t mon_bin_vma_fault(struct vm_fault *vmf)
1232{
1233        struct mon_reader_bin *rp = vmf->vma->vm_private_data;
1234        unsigned long offset, chunk_idx;
1235        struct page *pageptr;
1236
1237        mutex_lock(&rp->fetch_lock);
1238        offset = vmf->pgoff << PAGE_SHIFT;
1239        if (offset >= rp->b_size) {
1240                mutex_unlock(&rp->fetch_lock);
1241                return VM_FAULT_SIGBUS;
1242        }
1243        chunk_idx = offset / CHUNK_SIZE;
1244        pageptr = rp->b_vec[chunk_idx].pg;
1245        get_page(pageptr);
1246        mutex_unlock(&rp->fetch_lock);
1247        vmf->page = pageptr;
1248        return 0;
1249}
1250
1251static const struct vm_operations_struct mon_bin_vm_ops = {
1252        .open =     mon_bin_vma_open,
1253        .close =    mon_bin_vma_close,
1254        .fault =    mon_bin_vma_fault,
1255};
1256
1257static int mon_bin_mmap(struct file *filp, struct vm_area_struct *vma)
1258{
1259        /* don't do anything here: "fault" will set up page table entries */
1260        vma->vm_ops = &mon_bin_vm_ops;
1261        vma->vm_flags |= VM_DONTEXPAND | VM_DONTDUMP;
1262        vma->vm_private_data = filp->private_data;
1263        mon_bin_vma_open(vma);
1264        return 0;
1265}
1266
1267static const struct file_operations mon_fops_binary = {
1268        .owner =        THIS_MODULE,
1269        .open =         mon_bin_open,
1270        .llseek =       no_llseek,
1271        .read =         mon_bin_read,
1272        /* .write =     mon_text_write, */
1273        .poll =         mon_bin_poll,
1274        .unlocked_ioctl = mon_bin_ioctl,
1275#ifdef CONFIG_COMPAT
1276        .compat_ioctl = mon_bin_compat_ioctl,
1277#endif
1278        .release =      mon_bin_release,
1279        .mmap =         mon_bin_mmap,
1280};
1281
1282static int mon_bin_wait_event(struct file *file, struct mon_reader_bin *rp)
1283{
1284        DECLARE_WAITQUEUE(waita, current);
1285        unsigned long flags;
1286
1287        add_wait_queue(&rp->b_wait, &waita);
1288        set_current_state(TASK_INTERRUPTIBLE);
1289
1290        spin_lock_irqsave(&rp->b_lock, flags);
1291        while (MON_RING_EMPTY(rp)) {
1292                spin_unlock_irqrestore(&rp->b_lock, flags);
1293
1294                if (file->f_flags & O_NONBLOCK) {
1295                        set_current_state(TASK_RUNNING);
1296                        remove_wait_queue(&rp->b_wait, &waita);
1297                        return -EWOULDBLOCK; /* Same as EAGAIN in Linux */
1298                }
1299                schedule();
1300                if (signal_pending(current)) {
1301                        remove_wait_queue(&rp->b_wait, &waita);
1302                        return -EINTR;
1303                }
1304                set_current_state(TASK_INTERRUPTIBLE);
1305
1306                spin_lock_irqsave(&rp->b_lock, flags);
1307        }
1308        spin_unlock_irqrestore(&rp->b_lock, flags);
1309
1310        set_current_state(TASK_RUNNING);
1311        remove_wait_queue(&rp->b_wait, &waita);
1312        return 0;
1313}
1314
1315static int mon_alloc_buff(struct mon_pgmap *map, int npages)
1316{
1317        int n;
1318        unsigned long vaddr;
1319
1320        for (n = 0; n < npages; n++) {
1321                vaddr = get_zeroed_page(GFP_KERNEL);
1322                if (vaddr == 0) {
1323                        while (n-- != 0)
1324                                free_page((unsigned long) map[n].ptr);
1325                        return -ENOMEM;
1326                }
1327                map[n].ptr = (unsigned char *) vaddr;
1328                map[n].pg = virt_to_page((void *) vaddr);
1329        }
1330        return 0;
1331}
1332
1333static void mon_free_buff(struct mon_pgmap *map, int npages)
1334{
1335        int n;
1336
1337        for (n = 0; n < npages; n++)
1338                free_page((unsigned long) map[n].ptr);
1339}
1340
1341int mon_bin_add(struct mon_bus *mbus, const struct usb_bus *ubus)
1342{
1343        struct device *dev;
1344        unsigned minor = ubus? ubus->busnum: 0;
1345
1346        if (minor >= MON_BIN_MAX_MINOR)
1347                return 0;
1348
1349        dev = device_create(mon_bin_class, ubus ? ubus->controller : NULL,
1350                            MKDEV(MAJOR(mon_bin_dev0), minor), NULL,
1351                            "usbmon%d", minor);
1352        if (IS_ERR(dev))
1353                return 0;
1354
1355        mbus->classdev = dev;
1356        return 1;
1357}
1358
1359void mon_bin_del(struct mon_bus *mbus)
1360{
1361        device_destroy(mon_bin_class, mbus->classdev->devt);
1362}
1363
1364int __init mon_bin_init(void)
1365{
1366        int rc;
1367
1368        mon_bin_class = class_create(THIS_MODULE, "usbmon");
1369        if (IS_ERR(mon_bin_class)) {
1370                rc = PTR_ERR(mon_bin_class);
1371                goto err_class;
1372        }
1373
1374        rc = alloc_chrdev_region(&mon_bin_dev0, 0, MON_BIN_MAX_MINOR, "usbmon");
1375        if (rc < 0)
1376                goto err_dev;
1377
1378        cdev_init(&mon_bin_cdev, &mon_fops_binary);
1379        mon_bin_cdev.owner = THIS_MODULE;
1380
1381        rc = cdev_add(&mon_bin_cdev, mon_bin_dev0, MON_BIN_MAX_MINOR);
1382        if (rc < 0)
1383                goto err_add;
1384
1385        return 0;
1386
1387err_add:
1388        unregister_chrdev_region(mon_bin_dev0, MON_BIN_MAX_MINOR);
1389err_dev:
1390        class_destroy(mon_bin_class);
1391err_class:
1392        return rc;
1393}
1394
1395void mon_bin_exit(void)
1396{
1397        cdev_del(&mon_bin_cdev);
1398        unregister_chrdev_region(mon_bin_dev0, MON_BIN_MAX_MINOR);
1399        class_destroy(mon_bin_class);
1400}
1401