--- /dev/null
+/*
+ * The USB Monitor, inspired by Dave Harding's USBMon.
+ *
+ * This is a binary format reader.
+ *
+ * Copyright (C) 2006 Paolo Abeni (paolo.abeni@email.it)
+ * Copyright (C) 2006,2007 Pete Zaitcev (zaitcev@redhat.com)
+ */
+
+#include <linux/kernel.h>
+#include <linux/types.h>
+#include <linux/fs.h>
+#include <linux/cdev.h>
+#include <linux/export.h>
+#include <linux/usb.h>
+#include <linux/poll.h>
+#include <linux/compat.h>
+#include <linux/mm.h>
+#include <linux/scatterlist.h>
+#include <linux/slab.h>
+
+#include <asm/uaccess.h>
+
+#include "usb_mon.h"
+
+/*
+ * Defined by USB 2.0 clause 9.3, table 9.2.
+ */
+#define SETUP_LEN 8
+
+/* ioctl macros */
+#define MON_IOC_MAGIC 0x92
+
+#define MON_IOCQ_URB_LEN _IO(MON_IOC_MAGIC, 1)
+/* #2 used to be MON_IOCX_URB, removed before it got into Linus tree */
+#define MON_IOCG_STATS _IOR(MON_IOC_MAGIC, 3, struct mon_bin_stats)
+#define MON_IOCT_RING_SIZE _IO(MON_IOC_MAGIC, 4)
+#define MON_IOCQ_RING_SIZE _IO(MON_IOC_MAGIC, 5)
+#define MON_IOCX_GET _IOW(MON_IOC_MAGIC, 6, struct mon_bin_get)
+#define MON_IOCX_MFETCH _IOWR(MON_IOC_MAGIC, 7, struct mon_bin_mfetch)
+#define MON_IOCH_MFLUSH _IO(MON_IOC_MAGIC, 8)
+/* #9 was MON_IOCT_SETAPI */
+#define MON_IOCX_GETX _IOW(MON_IOC_MAGIC, 10, struct mon_bin_get)
+
+#ifdef CONFIG_COMPAT
+#define MON_IOCX_GET32 _IOW(MON_IOC_MAGIC, 6, struct mon_bin_get32)
+#define MON_IOCX_MFETCH32 _IOWR(MON_IOC_MAGIC, 7, struct mon_bin_mfetch32)
+#define MON_IOCX_GETX32 _IOW(MON_IOC_MAGIC, 10, struct mon_bin_get32)
+#endif
+
+/*
+ * Some architectures have enormous basic pages (16KB for ia64, 64KB for ppc).
+ * But it's all right. Just use a simple way to make sure the chunk is never
+ * smaller than a page.
+ *
+ * N.B. An application does not know our chunk size.
+ *
+ * Woops, get_zeroed_page() returns a single page. I guess we're stuck with
+ * page-sized chunks for the time being.
+ */
+#define CHUNK_SIZE PAGE_SIZE
+#define CHUNK_ALIGN(x) (((x)+CHUNK_SIZE-1) & ~(CHUNK_SIZE-1))
+
+/*
+ * The magic limit was calculated so that it allows the monitoring
+ * application to pick data once in two ticks. This way, another application,
+ * which presumably drives the bus, gets to hog CPU, yet we collect our data.
+ * If HZ is 100, a 480 mbit/s bus drives 614 KB every jiffy. USB has an
+ * enormous overhead built into the bus protocol, so we need about 1000 KB.
+ *
+ * This is still too much for most cases, where we just snoop a few
+ * descriptor fetches for enumeration. So, the default is a "reasonable"
+ * amount for systems with HZ=250 and incomplete bus saturation.
+ *
+ * XXX What about multi-megabyte URBs which take minutes to transfer?
+ */
+#define BUFF_MAX CHUNK_ALIGN(1200*1024)
+#define BUFF_DFL CHUNK_ALIGN(300*1024)
+#define BUFF_MIN CHUNK_ALIGN(8*1024)
+
+/*
+ * The per-event API header (2 per URB).
+ *
+ * This structure is seen in userland as defined by the documentation.
+ */
+struct mon_bin_hdr {
+ u64 id; /* URB ID - from submission to callback */
+ unsigned char type; /* Same as in text API; extensible. */
+ unsigned char xfer_type; /* ISO, Intr, Control, Bulk */
+ unsigned char epnum; /* Endpoint number and transfer direction */
+ unsigned char devnum; /* Device address */
+ unsigned short busnum; /* Bus number */
+ char flag_setup;
+ char flag_data;
+ s64 ts_sec; /* gettimeofday */
+ s32 ts_usec; /* gettimeofday */
+ int status;
+ unsigned int len_urb; /* Length of data (submitted or actual) */
+ unsigned int len_cap; /* Delivered length */
+ union {
+ unsigned char setup[SETUP_LEN]; /* Only for Control S-type */
+ struct iso_rec {
+ int error_count;
+ int numdesc;
+ } iso;
+ } s;
+ int interval;
+ int start_frame;
+ unsigned int xfer_flags;
+ unsigned int ndesc; /* Actual number of ISO descriptors */
+};
+
+/*
+ * ISO vector, packed into the head of data stream.
+ * This has to take 16 bytes to make sure that the end of buffer
+ * wrap is not happening in the middle of a descriptor.
+ */
+struct mon_bin_isodesc {
+ int iso_status;
+ unsigned int iso_off;
+ unsigned int iso_len;
+ u32 _pad;
+};
+
+/* per file statistic */
+struct mon_bin_stats {
+ u32 queued;
+ u32 dropped;
+};
+
+struct mon_bin_get {
+ struct mon_bin_hdr __user *hdr; /* Can be 48 bytes or 64. */
+ void __user *data;
+ size_t alloc; /* Length of data (can be zero) */
+};
+
+struct mon_bin_mfetch {
+ u32 __user *offvec; /* Vector of events fetched */
+ u32 nfetch; /* Number of events to fetch (out: fetched) */
+ u32 nflush; /* Number of events to flush */
+};
+
+#ifdef CONFIG_COMPAT
+struct mon_bin_get32 {
+ u32 hdr32;
+ u32 data32;
+ u32 alloc32;
+};
+
+struct mon_bin_mfetch32 {
+ u32 offvec32;
+ u32 nfetch32;
+ u32 nflush32;
+};
+#endif
+
+/* Having these two values same prevents wrapping of the mon_bin_hdr */
+#define PKT_ALIGN 64
+#define PKT_SIZE 64
+
+#define PKT_SZ_API0 48 /* API 0 (2.6.20) size */
+#define PKT_SZ_API1 64 /* API 1 size: extra fields */
+
+#define ISODESC_MAX 128 /* Same number as usbfs allows, 2048 bytes. */
+
+/* max number of USB bus supported */
+#define MON_BIN_MAX_MINOR 128
+
+/*
+ * The buffer: map of used pages.
+ */
+struct mon_pgmap {
+ struct page *pg;
+ unsigned char *ptr; /* XXX just use page_to_virt everywhere? */
+};
+
+/*
+ * This gets associated with an open file struct.
+ */
+struct mon_reader_bin {
+ /* The buffer: one per open. */
+ spinlock_t b_lock; /* Protect b_cnt, b_in */
+ unsigned int b_size; /* Current size of the buffer - bytes */
+ unsigned int b_cnt; /* Bytes used */
+ unsigned int b_in, b_out; /* Offsets into buffer - bytes */
+ unsigned int b_read; /* Amount of read data in curr. pkt. */
+ struct mon_pgmap *b_vec; /* The map array */
+ wait_queue_head_t b_wait; /* Wait for data here */
+
+ struct mutex fetch_lock; /* Protect b_read, b_out */
+ int mmap_active;
+
+ /* A list of these is needed for "bus 0". Some time later. */
+ struct mon_reader r;
+
+ /* Stats */
+ unsigned int cnt_lost;
+};
+
+static inline struct mon_bin_hdr *MON_OFF2HDR(const struct mon_reader_bin *rp,
+ unsigned int offset)
+{
+ return (struct mon_bin_hdr *)
+ (rp->b_vec[offset / CHUNK_SIZE].ptr + offset % CHUNK_SIZE);
+}
+
+#define MON_RING_EMPTY(rp) ((rp)->b_cnt == 0)
+
+static unsigned char xfer_to_pipe[4] = {
+ PIPE_CONTROL, PIPE_ISOCHRONOUS, PIPE_BULK, PIPE_INTERRUPT
+};
+
+static struct class *mon_bin_class;
+static dev_t mon_bin_dev0;
+static struct cdev mon_bin_cdev;
+
+static void mon_buff_area_fill(const struct mon_reader_bin *rp,
+ unsigned int offset, unsigned int size);
+static int mon_bin_wait_event(struct file *file, struct mon_reader_bin *rp);
+static int mon_alloc_buff(struct mon_pgmap *map, int npages);
+static void mon_free_buff(struct mon_pgmap *map, int npages);
+
+/*
+ * This is a "chunked memcpy". It does not manipulate any counters.
+ */
+static unsigned int mon_copy_to_buff(const struct mon_reader_bin *this,
+ unsigned int off, const unsigned char *from, unsigned int length)
+{
+ unsigned int step_len;
+ unsigned char *buf;
+ unsigned int in_page;
+
+ while (length) {
+ /*
+ * Determine step_len.
+ */
+ step_len = length;
+ in_page = CHUNK_SIZE - (off & (CHUNK_SIZE-1));
+ if (in_page < step_len)
+ step_len = in_page;
+
+ /*
+ * Copy data and advance pointers.
+ */
+ buf = this->b_vec[off / CHUNK_SIZE].ptr + off % CHUNK_SIZE;
+ memcpy(buf, from, step_len);
+ if ((off += step_len) >= this->b_size) off = 0;
+ from += step_len;
+ length -= step_len;
+ }
+ return off;
+}
+
+/*
+ * This is a little worse than the above because it's "chunked copy_to_user".
+ * The return value is an error code, not an offset.
+ */
+static int copy_from_buf(const struct mon_reader_bin *this, unsigned int off,
+ char __user *to, int length)
+{
+ unsigned int step_len;
+ unsigned char *buf;
+ unsigned int in_page;
+
+ while (length) {
+ /*
+ * Determine step_len.
+ */
+ step_len = length;
+ in_page = CHUNK_SIZE - (off & (CHUNK_SIZE-1));
+ if (in_page < step_len)
+ step_len = in_page;
+
+ /*
+ * Copy data and advance pointers.
+ */
+ buf = this->b_vec[off / CHUNK_SIZE].ptr + off % CHUNK_SIZE;
+ if (copy_to_user(to, buf, step_len))
+ return -EINVAL;
+ if ((off += step_len) >= this->b_size) off = 0;
+ to += step_len;
+ length -= step_len;
+ }
+ return 0;
+}
+
+/*
+ * Allocate an (aligned) area in the buffer.
+ * This is called under b_lock.
+ * Returns ~0 on failure.
+ */
+static unsigned int mon_buff_area_alloc(struct mon_reader_bin *rp,
+ unsigned int size)
+{
+ unsigned int offset;
+
+ size = (size + PKT_ALIGN-1) & ~(PKT_ALIGN-1);
+ if (rp->b_cnt + size > rp->b_size)
+ return ~0;
+ offset = rp->b_in;
+ rp->b_cnt += size;
+ if ((rp->b_in += size) >= rp->b_size)
+ rp->b_in -= rp->b_size;
+ return offset;
+}
+
+/*
+ * This is the same thing as mon_buff_area_alloc, only it does not allow
+ * buffers to wrap. This is needed by applications which pass references
+ * into mmap-ed buffers up their stacks (libpcap can do that).
+ *
+ * Currently, we always have the header stuck with the data, although
+ * it is not strictly speaking necessary.
+ *
+ * When a buffer would wrap, we place a filler packet to mark the space.
+ */
+static unsigned int mon_buff_area_alloc_contiguous(struct mon_reader_bin *rp,
+ unsigned int size)
+{
+ unsigned int offset;
+ unsigned int fill_size;
+
+ size = (size + PKT_ALIGN-1) & ~(PKT_ALIGN-1);
+ if (rp->b_cnt + size > rp->b_size)
+ return ~0;
+ if (rp->b_in + size > rp->b_size) {
+ /*
+ * This would wrap. Find if we still have space after
+ * skipping to the end of the buffer. If we do, place
+ * a filler packet and allocate a new packet.
+ */
+ fill_size = rp->b_size - rp->b_in;
+ if (rp->b_cnt + size + fill_size > rp->b_size)
+ return ~0;
+ mon_buff_area_fill(rp, rp->b_in, fill_size);
+
+ offset = 0;
+ rp->b_in = size;
+ rp->b_cnt += size + fill_size;
+ } else if (rp->b_in + size == rp->b_size) {
+ offset = rp->b_in;
+ rp->b_in = 0;
+ rp->b_cnt += size;
+ } else {
+ offset = rp->b_in;
+ rp->b_in += size;
+ rp->b_cnt += size;
+ }
+ return offset;
+}
+
+/*
+ * Return a few (kilo-)bytes to the head of the buffer.
+ * This is used if a data fetch fails.
+ */
+static void mon_buff_area_shrink(struct mon_reader_bin *rp, unsigned int size)
+{
+
+ /* size &= ~(PKT_ALIGN-1); -- we're called with aligned size */
+ rp->b_cnt -= size;
+ if (rp->b_in < size)
+ rp->b_in += rp->b_size;
+ rp->b_in -= size;
+}
+
+/*
+ * This has to be called under both b_lock and fetch_lock, because
+ * it accesses both b_cnt and b_out.
+ */
+static void mon_buff_area_free(struct mon_reader_bin *rp, unsigned int size)
+{
+
+ size = (size + PKT_ALIGN-1) & ~(PKT_ALIGN-1);
+ rp->b_cnt -= size;
+ if ((rp->b_out += size) >= rp->b_size)
+ rp->b_out -= rp->b_size;
+}
+
+static void mon_buff_area_fill(const struct mon_reader_bin *rp,
+ unsigned int offset, unsigned int size)
+{
+ struct mon_bin_hdr *ep;
+
+ ep = MON_OFF2HDR(rp, offset);
+ memset(ep, 0, PKT_SIZE);
+ ep->type = '@';
+ ep->len_cap = size - PKT_SIZE;
+}
+
+static inline char mon_bin_get_setup(unsigned char *setupb,
+ const struct urb *urb, char ev_type)
+{
+
+ if (urb->setup_packet == NULL)
+ return 'Z';
+ memcpy(setupb, urb->setup_packet, SETUP_LEN);
+ return 0;
+}
+
+static unsigned int mon_bin_get_data(const struct mon_reader_bin *rp,
+ unsigned int offset, struct urb *urb, unsigned int length,
+ char *flag)
+{
+ int i;
+ struct scatterlist *sg;
+ unsigned int this_len;
+
+ *flag = 0;
+ if (urb->num_sgs == 0) {
+ if (urb->transfer_buffer == NULL) {
+ *flag = 'Z';
+ return length;
+ }
+ mon_copy_to_buff(rp, offset, urb->transfer_buffer, length);
+ length = 0;
+
+ } else {
+ /* If IOMMU coalescing occurred, we cannot trust sg_page */
+ if (urb->transfer_flags & URB_DMA_SG_COMBINED) {
+ *flag = 'D';
+ return length;
+ }
+
+ /* Copy up to the first non-addressable segment */
+ for_each_sg(urb->sg, sg, urb->num_sgs, i) {
+ if (length == 0 || PageHighMem(sg_page(sg)))
+ break;
+ this_len = min_t(unsigned int, sg->length, length);
+ offset = mon_copy_to_buff(rp, offset, sg_virt(sg),
+ this_len);
+ length -= this_len;
+ }
+ if (i == 0)
+ *flag = 'D';
+ }
+
+ return length;
+}
+
+/*
+ * This is the look-ahead pass in case of 'C Zi', when actual_length cannot
+ * be used to determine the length of the whole contiguous buffer.
+ */
+static unsigned int mon_bin_collate_isodesc(const struct mon_reader_bin *rp,
+ struct urb *urb, unsigned int ndesc)
+{
+ struct usb_iso_packet_descriptor *fp;
+ unsigned int length;
+
+ length = 0;
+ fp = urb->iso_frame_desc;
+ while (ndesc-- != 0) {
+ if (fp->actual_length != 0) {
+ if (fp->offset + fp->actual_length > length)
+ length = fp->offset + fp->actual_length;
+ }
+ fp++;
+ }
+ return length;
+}
+
+static void mon_bin_get_isodesc(const struct mon_reader_bin *rp,
+ unsigned int offset, struct urb *urb, char ev_type, unsigned int ndesc)
+{
+ struct mon_bin_isodesc *dp;
+ struct usb_iso_packet_descriptor *fp;
+
+ fp = urb->iso_frame_desc;
+ while (ndesc-- != 0) {
+ dp = (struct mon_bin_isodesc *)
+ (rp->b_vec[offset / CHUNK_SIZE].ptr + offset % CHUNK_SIZE);
+ dp->iso_status = fp->status;
+ dp->iso_off = fp->offset;
+ dp->iso_len = (ev_type == 'S') ? fp->length : fp->actual_length;
+ dp->_pad = 0;
+ if ((offset += sizeof(struct mon_bin_isodesc)) >= rp->b_size)
+ offset = 0;
+ fp++;
+ }
+}
+
+static void mon_bin_event(struct mon_reader_bin *rp, struct urb *urb,
+ char ev_type, int status)
+{
+ const struct usb_endpoint_descriptor *epd = &urb->ep->desc;
+ struct timeval ts;
+ unsigned long flags;
+ unsigned int urb_length;
+ unsigned int offset;
+ unsigned int length;
+ unsigned int delta;
+ unsigned int ndesc, lendesc;
+ unsigned char dir;
+ struct mon_bin_hdr *ep;
+ char data_tag = 0;
+
+ do_gettimeofday(&ts);
+
+ spin_lock_irqsave(&rp->b_lock, flags);
+
+ /*
+ * Find the maximum allowable length, then allocate space.
+ */
+ urb_length = (ev_type == 'S') ?
+ urb->transfer_buffer_length : urb->actual_length;
+ length = urb_length;
+
+ if (usb_endpoint_xfer_isoc(epd)) {
+ if (urb->number_of_packets < 0) {
+ ndesc = 0;
+ } else if (urb->number_of_packets >= ISODESC_MAX) {
+ ndesc = ISODESC_MAX;
+ } else {
+ ndesc = urb->number_of_packets;
+ }
+ if (ev_type == 'C' && usb_urb_dir_in(urb))
+ length = mon_bin_collate_isodesc(rp, urb, ndesc);
+ } else {
+ ndesc = 0;
+ }
+ lendesc = ndesc*sizeof(struct mon_bin_isodesc);
+
+ /* not an issue unless there's a subtle bug in a HCD somewhere */
+ if (length >= urb->transfer_buffer_length)
+ length = urb->transfer_buffer_length;
+
+ if (length >= rp->b_size/5)
+ length = rp->b_size/5;
+
+ if (usb_urb_dir_in(urb)) {
+ if (ev_type == 'S') {
+ length = 0;
+ data_tag = '<';
+ }
+ /* Cannot rely on endpoint number in case of control ep.0 */
+ dir = USB_DIR_IN;
+ } else {
+ if (ev_type == 'C') {
+ length = 0;
+ data_tag = '>';
+ }
+ dir = 0;
+ }
+
+ if (rp->mmap_active) {
+ offset = mon_buff_area_alloc_contiguous(rp,
+ length + PKT_SIZE + lendesc);
+ } else {
+ offset = mon_buff_area_alloc(rp, length + PKT_SIZE + lendesc);
+ }
+ if (offset == ~0) {
+ rp->cnt_lost++;
+ spin_unlock_irqrestore(&rp->b_lock, flags);
+ return;
+ }
+
+ ep = MON_OFF2HDR(rp, offset);
+ if ((offset += PKT_SIZE) >= rp->b_size) offset = 0;
+
+ /*
+ * Fill the allocated area.
+ */
+ memset(ep, 0, PKT_SIZE);
+ ep->type = ev_type;
+ ep->xfer_type = xfer_to_pipe[usb_endpoint_type(epd)];
+ ep->epnum = dir | usb_endpoint_num(epd);
+ ep->devnum = urb->dev->devnum;
+ ep->busnum = urb->dev->bus->busnum;
+ ep->id = (unsigned long) urb;
+ ep->ts_sec = ts.tv_sec;
+ ep->ts_usec = ts.tv_usec;
+ ep->status = status;
+ ep->len_urb = urb_length;
+ ep->len_cap = length + lendesc;
+ ep->xfer_flags = urb->transfer_flags;
+
+ if (usb_endpoint_xfer_int(epd)) {
+ ep->interval = urb->interval;
+ } else if (usb_endpoint_xfer_isoc(epd)) {
+ ep->interval = urb->interval;
+ ep->start_frame = urb->start_frame;
+ ep->s.iso.error_count = urb->error_count;
+ ep->s.iso.numdesc = urb->number_of_packets;
+ }
+
+ if (usb_endpoint_xfer_control(epd) && ev_type == 'S') {
+ ep->flag_setup = mon_bin_get_setup(ep->s.setup, urb, ev_type);
+ } else {
+ ep->flag_setup = '-';
+ }
+
+ if (ndesc != 0) {
+ ep->ndesc = ndesc;
+ mon_bin_get_isodesc(rp, offset, urb, ev_type, ndesc);
+ if ((offset += lendesc) >= rp->b_size)
+ offset -= rp->b_size;
+ }
+
+ if (length != 0) {
+ length = mon_bin_get_data(rp, offset, urb, length,
+ &ep->flag_data);
+ if (length > 0) {
+ delta = (ep->len_cap + PKT_ALIGN-1) & ~(PKT_ALIGN-1);
+ ep->len_cap -= length;
+ delta -= (ep->len_cap + PKT_ALIGN-1) & ~(PKT_ALIGN-1);
+ mon_buff_area_shrink(rp, delta);
+ }
+ } else {
+ ep->flag_data = data_tag;
+ }
+
+ spin_unlock_irqrestore(&rp->b_lock, flags);
+
+ wake_up(&rp->b_wait);
+}
+
+static void mon_bin_submit(void *data, struct urb *urb)
+{
+ struct mon_reader_bin *rp = data;
+ mon_bin_event(rp, urb, 'S', -EINPROGRESS);
+}
+
+static void mon_bin_complete(void *data, struct urb *urb, int status)
+{
+ struct mon_reader_bin *rp = data;
+ mon_bin_event(rp, urb, 'C', status);
+}
+
+static void mon_bin_error(void *data, struct urb *urb, int error)
+{
+ struct mon_reader_bin *rp = data;
+ struct timeval ts;
+ unsigned long flags;
+ unsigned int offset;
+ struct mon_bin_hdr *ep;
+
+ do_gettimeofday(&ts);
+
+ spin_lock_irqsave(&rp->b_lock, flags);
+
+ offset = mon_buff_area_alloc(rp, PKT_SIZE);
+ if (offset == ~0) {
+ /* Not incrementing cnt_lost. Just because. */
+ spin_unlock_irqrestore(&rp->b_lock, flags);
+ return;
+ }
+
+ ep = MON_OFF2HDR(rp, offset);
+
+ memset(ep, 0, PKT_SIZE);
+ ep->type = 'E';
+ ep->xfer_type = xfer_to_pipe[usb_endpoint_type(&urb->ep->desc)];
+ ep->epnum = usb_urb_dir_in(urb) ? USB_DIR_IN : 0;
+ ep->epnum |= usb_endpoint_num(&urb->ep->desc);
+ ep->devnum = urb->dev->devnum;
+ ep->busnum = urb->dev->bus->busnum;
+ ep->id = (unsigned long) urb;
+ ep->ts_sec = ts.tv_sec;
+ ep->ts_usec = ts.tv_usec;
+ ep->status = error;
+
+ ep->flag_setup = '-';
+ ep->flag_data = 'E';
+
+ spin_unlock_irqrestore(&rp->b_lock, flags);
+
+ wake_up(&rp->b_wait);
+}
+
+static int mon_bin_open(struct inode *inode, struct file *file)
+{
+ struct mon_bus *mbus;
+ struct mon_reader_bin *rp;
+ size_t size;
+ int rc;
+
+ mutex_lock(&mon_lock);
+ if ((mbus = mon_bus_lookup(iminor(inode))) == NULL) {
+ mutex_unlock(&mon_lock);
+ return -ENODEV;
+ }
+ if (mbus != &mon_bus0 && mbus->u_bus == NULL) {
+ printk(KERN_ERR TAG ": consistency error on open\n");
+ mutex_unlock(&mon_lock);
+ return -ENODEV;
+ }
+
+ rp = kzalloc(sizeof(struct mon_reader_bin), GFP_KERNEL);
+ if (rp == NULL) {
+ rc = -ENOMEM;
+ goto err_alloc;
+ }
+ spin_lock_init(&rp->b_lock);
+ init_waitqueue_head(&rp->b_wait);
+ mutex_init(&rp->fetch_lock);
+ rp->b_size = BUFF_DFL;
+
+ size = sizeof(struct mon_pgmap) * (rp->b_size/CHUNK_SIZE);
+ if ((rp->b_vec = kzalloc(size, GFP_KERNEL)) == NULL) {
+ rc = -ENOMEM;
+ goto err_allocvec;
+ }
+
+ if ((rc = mon_alloc_buff(rp->b_vec, rp->b_size/CHUNK_SIZE)) < 0)
+ goto err_allocbuff;
+
+ rp->r.m_bus = mbus;
+ rp->r.r_data = rp;
+ rp->r.rnf_submit = mon_bin_submit;
+ rp->r.rnf_error = mon_bin_error;
+ rp->r.rnf_complete = mon_bin_complete;
+
+ mon_reader_add(mbus, &rp->r);
+
+ file->private_data = rp;
+ mutex_unlock(&mon_lock);
+ return 0;
+
+err_allocbuff:
+ kfree(rp->b_vec);
+err_allocvec:
+ kfree(rp);
+err_alloc:
+ mutex_unlock(&mon_lock);
+ return rc;
+}
+
+/*
+ * Extract an event from buffer and copy it to user space.
+ * Wait if there is no event ready.
+ * Returns zero or error.
+ */
+static int mon_bin_get_event(struct file *file, struct mon_reader_bin *rp,
+ struct mon_bin_hdr __user *hdr, unsigned int hdrbytes,
+ void __user *data, unsigned int nbytes)
+{
+ unsigned long flags;
+ struct mon_bin_hdr *ep;
+ size_t step_len;
+ unsigned int offset;
+ int rc;
+
+ mutex_lock(&rp->fetch_lock);
+
+ if ((rc = mon_bin_wait_event(file, rp)) < 0) {
+ mutex_unlock(&rp->fetch_lock);
+ return rc;
+ }
+
+ ep = MON_OFF2HDR(rp, rp->b_out);
+
+ if (copy_to_user(hdr, ep, hdrbytes)) {
+ mutex_unlock(&rp->fetch_lock);
+ return -EFAULT;
+ }
+
+ step_len = min(ep->len_cap, nbytes);
+ if ((offset = rp->b_out + PKT_SIZE) >= rp->b_size) offset = 0;
+
+ if (copy_from_buf(rp, offset, data, step_len)) {
+ mutex_unlock(&rp->fetch_lock);
+ return -EFAULT;
+ }
+
+ spin_lock_irqsave(&rp->b_lock, flags);
+ mon_buff_area_free(rp, PKT_SIZE + ep->len_cap);
+ spin_unlock_irqrestore(&rp->b_lock, flags);
+ rp->b_read = 0;
+
+ mutex_unlock(&rp->fetch_lock);
+ return 0;
+}
+
+static int mon_bin_release(struct inode *inode, struct file *file)
+{
+ struct mon_reader_bin *rp = file->private_data;
+ struct mon_bus* mbus = rp->r.m_bus;
+
+ mutex_lock(&mon_lock);
+
+ if (mbus->nreaders <= 0) {
+ printk(KERN_ERR TAG ": consistency error on close\n");
+ mutex_unlock(&mon_lock);
+ return 0;
+ }
+ mon_reader_del(mbus, &rp->r);
+
+ mon_free_buff(rp->b_vec, rp->b_size/CHUNK_SIZE);
+ kfree(rp->b_vec);
+ kfree(rp);
+
+ mutex_unlock(&mon_lock);
+ return 0;
+}
+
+static ssize_t mon_bin_read(struct file *file, char __user *buf,
+ size_t nbytes, loff_t *ppos)
+{
+ struct mon_reader_bin *rp = file->private_data;
+ unsigned int hdrbytes = PKT_SZ_API0;
+ unsigned long flags;
+ struct mon_bin_hdr *ep;
+ unsigned int offset;
+ size_t step_len;
+ char *ptr;
+ ssize_t done = 0;
+ int rc;
+
+ mutex_lock(&rp->fetch_lock);
+
+ if ((rc = mon_bin_wait_event(file, rp)) < 0) {
+ mutex_unlock(&rp->fetch_lock);
+ return rc;
+ }
+
+ ep = MON_OFF2HDR(rp, rp->b_out);
+
+ if (rp->b_read < hdrbytes) {
+ step_len = min(nbytes, (size_t)(hdrbytes - rp->b_read));
+ ptr = ((char *)ep) + rp->b_read;
+ if (step_len && copy_to_user(buf, ptr, step_len)) {
+ mutex_unlock(&rp->fetch_lock);
+ return -EFAULT;
+ }
+ nbytes -= step_len;
+ buf += step_len;
+ rp->b_read += step_len;
+ done += step_len;
+ }
+
+ if (rp->b_read >= hdrbytes) {
+ step_len = ep->len_cap;
+ step_len -= rp->b_read - hdrbytes;
+ if (step_len > nbytes)
+ step_len = nbytes;
+ offset = rp->b_out + PKT_SIZE;
+ offset += rp->b_read - hdrbytes;
+ if (offset >= rp->b_size)
+ offset -= rp->b_size;
+ if (copy_from_buf(rp, offset, buf, step_len)) {
+ mutex_unlock(&rp->fetch_lock);
+ return -EFAULT;
+ }
+ nbytes -= step_len;
+ buf += step_len;
+ rp->b_read += step_len;
+ done += step_len;
+ }
+
+ /*
+ * Check if whole packet was read, and if so, jump to the next one.
+ */
+ if (rp->b_read >= hdrbytes + ep->len_cap) {
+ spin_lock_irqsave(&rp->b_lock, flags);
+ mon_buff_area_free(rp, PKT_SIZE + ep->len_cap);
+ spin_unlock_irqrestore(&rp->b_lock, flags);
+ rp->b_read = 0;
+ }
+
+ mutex_unlock(&rp->fetch_lock);
+ return done;
+}
+
+/*
+ * Remove at most nevents from chunked buffer.
+ * Returns the number of removed events.
+ */
+static int mon_bin_flush(struct mon_reader_bin *rp, unsigned nevents)
+{
+ unsigned long flags;
+ struct mon_bin_hdr *ep;
+ int i;
+
+ mutex_lock(&rp->fetch_lock);
+ spin_lock_irqsave(&rp->b_lock, flags);
+ for (i = 0; i < nevents; ++i) {
+ if (MON_RING_EMPTY(rp))
+ break;
+
+ ep = MON_OFF2HDR(rp, rp->b_out);
+ mon_buff_area_free(rp, PKT_SIZE + ep->len_cap);
+ }
+ spin_unlock_irqrestore(&rp->b_lock, flags);
+ rp->b_read = 0;
+ mutex_unlock(&rp->fetch_lock);
+ return i;
+}
+
+/*
+ * Fetch at most max event offsets into the buffer and put them into vec.
+ * The events are usually freed later with mon_bin_flush.
+ * Return the effective number of events fetched.
+ */
+static int mon_bin_fetch(struct file *file, struct mon_reader_bin *rp,
+ u32 __user *vec, unsigned int max)
+{
+ unsigned int cur_out;
+ unsigned int bytes, avail;
+ unsigned int size;
+ unsigned int nevents;
+ struct mon_bin_hdr *ep;
+ unsigned long flags;
+ int rc;
+
+ mutex_lock(&rp->fetch_lock);
+
+ if ((rc = mon_bin_wait_event(file, rp)) < 0) {
+ mutex_unlock(&rp->fetch_lock);
+ return rc;
+ }
+
+ spin_lock_irqsave(&rp->b_lock, flags);
+ avail = rp->b_cnt;
+ spin_unlock_irqrestore(&rp->b_lock, flags);
+
+ cur_out = rp->b_out;
+ nevents = 0;
+ bytes = 0;
+ while (bytes < avail) {
+ if (nevents >= max)
+ break;
+
+ ep = MON_OFF2HDR(rp, cur_out);
+ if (put_user(cur_out, &vec[nevents])) {
+ mutex_unlock(&rp->fetch_lock);
+ return -EFAULT;
+ }
+
+ nevents++;
+ size = ep->len_cap + PKT_SIZE;
+ size = (size + PKT_ALIGN-1) & ~(PKT_ALIGN-1);
+ if ((cur_out += size) >= rp->b_size)
+ cur_out -= rp->b_size;
+ bytes += size;
+ }
+
+ mutex_unlock(&rp->fetch_lock);
+ return nevents;
+}
+
+/*
+ * Count events. This is almost the same as the above mon_bin_fetch,
+ * only we do not store offsets into user vector, and we have no limit.
+ */
+static int mon_bin_queued(struct mon_reader_bin *rp)
+{
+ unsigned int cur_out;
+ unsigned int bytes, avail;
+ unsigned int size;
+ unsigned int nevents;
+ struct mon_bin_hdr *ep;
+ unsigned long flags;
+
+ mutex_lock(&rp->fetch_lock);
+
+ spin_lock_irqsave(&rp->b_lock, flags);
+ avail = rp->b_cnt;
+ spin_unlock_irqrestore(&rp->b_lock, flags);
+
+ cur_out = rp->b_out;
+ nevents = 0;
+ bytes = 0;
+ while (bytes < avail) {
+ ep = MON_OFF2HDR(rp, cur_out);
+
+ nevents++;
+ size = ep->len_cap + PKT_SIZE;
+ size = (size + PKT_ALIGN-1) & ~(PKT_ALIGN-1);
+ if ((cur_out += size) >= rp->b_size)
+ cur_out -= rp->b_size;
+ bytes += size;
+ }
+
+ mutex_unlock(&rp->fetch_lock);
+ return nevents;
+}
+
+/*
+ */
+static long mon_bin_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+{
+ struct mon_reader_bin *rp = file->private_data;
+ // struct mon_bus* mbus = rp->r.m_bus;
+ int ret = 0;
+ struct mon_bin_hdr *ep;
+ unsigned long flags;
+
+ switch (cmd) {
+
+ case MON_IOCQ_URB_LEN:
+ /*
+ * N.B. This only returns the size of data, without the header.
+ */
+ spin_lock_irqsave(&rp->b_lock, flags);
+ if (!MON_RING_EMPTY(rp)) {
+ ep = MON_OFF2HDR(rp, rp->b_out);
+ ret = ep->len_cap;
+ }
+ spin_unlock_irqrestore(&rp->b_lock, flags);
+ break;
+
+ case MON_IOCQ_RING_SIZE:
+ ret = rp->b_size;
+ break;
+
+ case MON_IOCT_RING_SIZE:
+ /*
+ * Changing the buffer size will flush it's contents; the new
+ * buffer is allocated before releasing the old one to be sure
+ * the device will stay functional also in case of memory
+ * pressure.
+ */
+ {
+ int size;
+ struct mon_pgmap *vec;
+
+ if (arg < BUFF_MIN || arg > BUFF_MAX)
+ return -EINVAL;
+
+ size = CHUNK_ALIGN(arg);
+ if ((vec = kzalloc(sizeof(struct mon_pgmap) * (size/CHUNK_SIZE),
+ GFP_KERNEL)) == NULL) {
+ ret = -ENOMEM;
+ break;
+ }
+
+ ret = mon_alloc_buff(vec, size/CHUNK_SIZE);
+ if (ret < 0) {
+ kfree(vec);
+ break;
+ }
+
+ mutex_lock(&rp->fetch_lock);
+ spin_lock_irqsave(&rp->b_lock, flags);
+ mon_free_buff(rp->b_vec, rp->b_size/CHUNK_SIZE);
+ kfree(rp->b_vec);
+ rp->b_vec = vec;
+ rp->b_size = size;
+ rp->b_read = rp->b_in = rp->b_out = rp->b_cnt = 0;
+ rp->cnt_lost = 0;
+ spin_unlock_irqrestore(&rp->b_lock, flags);
+ mutex_unlock(&rp->fetch_lock);
+ }
+ break;
+
+ case MON_IOCH_MFLUSH:
+ ret = mon_bin_flush(rp, arg);
+ break;
+
+ case MON_IOCX_GET:
+ case MON_IOCX_GETX:
+ {
+ struct mon_bin_get getb;
+
+ if (copy_from_user(&getb, (void __user *)arg,
+ sizeof(struct mon_bin_get)))
+ return -EFAULT;
+
+ if (getb.alloc > 0x10000000) /* Want to cast to u32 */
+ return -EINVAL;
+ ret = mon_bin_get_event(file, rp, getb.hdr,
+ (cmd == MON_IOCX_GET)? PKT_SZ_API0: PKT_SZ_API1,
+ getb.data, (unsigned int)getb.alloc);
+ }
+ break;
+
+ case MON_IOCX_MFETCH:
+ {
+ struct mon_bin_mfetch mfetch;
+ struct mon_bin_mfetch __user *uptr;
+
+ uptr = (struct mon_bin_mfetch __user *)arg;
+
+ if (copy_from_user(&mfetch, uptr, sizeof(mfetch)))
+ return -EFAULT;
+
+ if (mfetch.nflush) {
+ ret = mon_bin_flush(rp, mfetch.nflush);
+ if (ret < 0)
+ return ret;
+ if (put_user(ret, &uptr->nflush))
+ return -EFAULT;
+ }
+ ret = mon_bin_fetch(file, rp, mfetch.offvec, mfetch.nfetch);
+ if (ret < 0)
+ return ret;
+ if (put_user(ret, &uptr->nfetch))
+ return -EFAULT;
+ ret = 0;
+ }
+ break;
+
+ case MON_IOCG_STATS: {
+ struct mon_bin_stats __user *sp;
+ unsigned int nevents;
+ unsigned int ndropped;
+
+ spin_lock_irqsave(&rp->b_lock, flags);
+ ndropped = rp->cnt_lost;
+ rp->cnt_lost = 0;
+ spin_unlock_irqrestore(&rp->b_lock, flags);
+ nevents = mon_bin_queued(rp);
+
+ sp = (struct mon_bin_stats __user *)arg;
+ if (put_user(ndropped, &sp->dropped))
+ return -EFAULT;
+ if (put_user(nevents, &sp->queued))
+ return -EFAULT;
+
+ }
+ break;
+
+ default:
+ return -ENOTTY;
+ }
+
+ return ret;
+}
+
+#ifdef CONFIG_COMPAT
+static long mon_bin_compat_ioctl(struct file *file,
+ unsigned int cmd, unsigned long arg)
+{
+ struct mon_reader_bin *rp = file->private_data;
+ int ret;
+
+ switch (cmd) {
+
+ case MON_IOCX_GET32:
+ case MON_IOCX_GETX32:
+ {
+ struct mon_bin_get32 getb;
+
+ if (copy_from_user(&getb, (void __user *)arg,
+ sizeof(struct mon_bin_get32)))
+ return -EFAULT;
+
+ ret = mon_bin_get_event(file, rp, compat_ptr(getb.hdr32),
+ (cmd == MON_IOCX_GET32)? PKT_SZ_API0: PKT_SZ_API1,
+ compat_ptr(getb.data32), getb.alloc32);
+ if (ret < 0)
+ return ret;
+ }
+ return 0;
+
+ case MON_IOCX_MFETCH32:
+ {
+ struct mon_bin_mfetch32 mfetch;
+ struct mon_bin_mfetch32 __user *uptr;
+
+ uptr = (struct mon_bin_mfetch32 __user *) compat_ptr(arg);
+
+ if (copy_from_user(&mfetch, uptr, sizeof(mfetch)))
+ return -EFAULT;
+
+ if (mfetch.nflush32) {
+ ret = mon_bin_flush(rp, mfetch.nflush32);
+ if (ret < 0)
+ return ret;
+ if (put_user(ret, &uptr->nflush32))
+ return -EFAULT;
+ }
+ ret = mon_bin_fetch(file, rp, compat_ptr(mfetch.offvec32),
+ mfetch.nfetch32);
+ if (ret < 0)
+ return ret;
+ if (put_user(ret, &uptr->nfetch32))
+ return -EFAULT;
+ }
+ return 0;
+
+ case MON_IOCG_STATS:
+ return mon_bin_ioctl(file, cmd, (unsigned long) compat_ptr(arg));
+
+ case MON_IOCQ_URB_LEN:
+ case MON_IOCQ_RING_SIZE:
+ case MON_IOCT_RING_SIZE:
+ case MON_IOCH_MFLUSH:
+ return mon_bin_ioctl(file, cmd, arg);
+
+ default:
+ ;
+ }
+ return -ENOTTY;
+}
+#endif /* CONFIG_COMPAT */
+
+static unsigned int
+mon_bin_poll(struct file *file, struct poll_table_struct *wait)
+{
+ struct mon_reader_bin *rp = file->private_data;
+ unsigned int mask = 0;
+ unsigned long flags;
+
+ if (file->f_mode & FMODE_READ)
+ poll_wait(file, &rp->b_wait, wait);
+
+ spin_lock_irqsave(&rp->b_lock, flags);
+ if (!MON_RING_EMPTY(rp))
+ mask |= POLLIN | POLLRDNORM; /* readable */
+ spin_unlock_irqrestore(&rp->b_lock, flags);
+ return mask;
+}
+
+/*
+ * open and close: just keep track of how many times the device is
+ * mapped, to use the proper memory allocation function.
+ */
+static void mon_bin_vma_open(struct vm_area_struct *vma)
+{
+ struct mon_reader_bin *rp = vma->vm_private_data;
+ rp->mmap_active++;
+}
+
+static void mon_bin_vma_close(struct vm_area_struct *vma)
+{
+ struct mon_reader_bin *rp = vma->vm_private_data;
+ rp->mmap_active--;
+}
+
+/*
+ * Map ring pages to user space.
+ */
+static int mon_bin_vma_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
+{
+ struct mon_reader_bin *rp = vma->vm_private_data;
+ unsigned long offset, chunk_idx;
+ struct page *pageptr;
+
+ offset = vmf->pgoff << PAGE_SHIFT;
+ if (offset >= rp->b_size)
+ return VM_FAULT_SIGBUS;
+ chunk_idx = offset / CHUNK_SIZE;
+ pageptr = rp->b_vec[chunk_idx].pg;
+ get_page(pageptr);
+ vmf->page = pageptr;
+ return 0;
+}
+
+static const struct vm_operations_struct mon_bin_vm_ops = {
+ .open = mon_bin_vma_open,
+ .close = mon_bin_vma_close,
+ .fault = mon_bin_vma_fault,
+};
+
+static int mon_bin_mmap(struct file *filp, struct vm_area_struct *vma)
+{
+ /* don't do anything here: "fault" will set up page table entries */
+ vma->vm_ops = &mon_bin_vm_ops;
+ vma->vm_flags |= VM_DONTEXPAND | VM_DONTDUMP;
+ vma->vm_private_data = filp->private_data;
+ mon_bin_vma_open(vma);
+ return 0;
+}
+
+static const struct file_operations mon_fops_binary = {
+ .owner = THIS_MODULE,
+ .open = mon_bin_open,
+ .llseek = no_llseek,
+ .read = mon_bin_read,
+ /* .write = mon_text_write, */
+ .poll = mon_bin_poll,
+ .unlocked_ioctl = mon_bin_ioctl,
+#ifdef CONFIG_COMPAT
+ .compat_ioctl = mon_bin_compat_ioctl,
+#endif
+ .release = mon_bin_release,
+ .mmap = mon_bin_mmap,
+};
+
+static int mon_bin_wait_event(struct file *file, struct mon_reader_bin *rp)
+{
+ DECLARE_WAITQUEUE(waita, current);
+ unsigned long flags;
+
+ add_wait_queue(&rp->b_wait, &waita);
+ set_current_state(TASK_INTERRUPTIBLE);
+
+ spin_lock_irqsave(&rp->b_lock, flags);
+ while (MON_RING_EMPTY(rp)) {
+ spin_unlock_irqrestore(&rp->b_lock, flags);
+
+ if (file->f_flags & O_NONBLOCK) {
+ set_current_state(TASK_RUNNING);
+ remove_wait_queue(&rp->b_wait, &waita);
+ return -EWOULDBLOCK; /* Same as EAGAIN in Linux */
+ }
+ schedule();
+ if (signal_pending(current)) {
+ remove_wait_queue(&rp->b_wait, &waita);
+ return -EINTR;
+ }
+ set_current_state(TASK_INTERRUPTIBLE);
+
+ spin_lock_irqsave(&rp->b_lock, flags);
+ }
+ spin_unlock_irqrestore(&rp->b_lock, flags);
+
+ set_current_state(TASK_RUNNING);
+ remove_wait_queue(&rp->b_wait, &waita);
+ return 0;
+}
+
+static int mon_alloc_buff(struct mon_pgmap *map, int npages)
+{
+ int n;
+ unsigned long vaddr;
+
+ for (n = 0; n < npages; n++) {
+ vaddr = get_zeroed_page(GFP_KERNEL);
+ if (vaddr == 0) {
+ while (n-- != 0)
+ free_page((unsigned long) map[n].ptr);
+ return -ENOMEM;
+ }
+ map[n].ptr = (unsigned char *) vaddr;
+ map[n].pg = virt_to_page((void *) vaddr);
+ }
+ return 0;
+}
+
+static void mon_free_buff(struct mon_pgmap *map, int npages)
+{
+ int n;
+
+ for (n = 0; n < npages; n++)
+ free_page((unsigned long) map[n].ptr);
+}
+
+int mon_bin_add(struct mon_bus *mbus, const struct usb_bus *ubus)
+{
+ struct device *dev;
+ unsigned minor = ubus? ubus->busnum: 0;
+
+ if (minor >= MON_BIN_MAX_MINOR)
+ return 0;
+
+ dev = device_create(mon_bin_class, ubus ? ubus->controller : NULL,
+ MKDEV(MAJOR(mon_bin_dev0), minor), NULL,
+ "usbmon%d", minor);
+ if (IS_ERR(dev))
+ return 0;
+
+ mbus->classdev = dev;
+ return 1;
+}
+
+void mon_bin_del(struct mon_bus *mbus)
+{
+ device_destroy(mon_bin_class, mbus->classdev->devt);
+}
+
+int __init mon_bin_init(void)
+{
+ int rc;
+
+ mon_bin_class = class_create(THIS_MODULE, "usbmon");
+ if (IS_ERR(mon_bin_class)) {
+ rc = PTR_ERR(mon_bin_class);
+ goto err_class;
+ }
+
+ rc = alloc_chrdev_region(&mon_bin_dev0, 0, MON_BIN_MAX_MINOR, "usbmon");
+ if (rc < 0)
+ goto err_dev;
+
+ cdev_init(&mon_bin_cdev, &mon_fops_binary);
+ mon_bin_cdev.owner = THIS_MODULE;
+
+ rc = cdev_add(&mon_bin_cdev, mon_bin_dev0, MON_BIN_MAX_MINOR);
+ if (rc < 0)
+ goto err_add;
+
+ return 0;
+
+err_add:
+ unregister_chrdev_region(mon_bin_dev0, MON_BIN_MAX_MINOR);
+err_dev:
+ class_destroy(mon_bin_class);
+err_class:
+ return rc;
+}
+
+void mon_bin_exit(void)
+{
+ cdev_del(&mon_bin_cdev);
+ unregister_chrdev_region(mon_bin_dev0, MON_BIN_MAX_MINOR);
+ class_destroy(mon_bin_class);
+}
Code Review / kvmfornfv.git / blobdiff