The '1t' type data consists of a stream of events, such as URB submission,
URB callback, submission error. Every event is a text line, which consists
-of whitespace separated words. The number of position of words may depend
+of whitespace separated words. The number or position of words may depend
on the event type, but there is a set of words, common for all types.
Here is the list of words, from left to right:
* Raw binary format and API
-TBD
+The overall architecture of the API is about the same as the one above,
+only the events are delivered in binary format. Each event is sent in
+the following structure (its name is made up, so that we can refer to it):
+
+struct usbmon_packet {
+ u64 id; /* 0: URB ID - from submission to callback */
+ unsigned char type; /* 8: Same as text; extensible. */
+ unsigned char xfer_type; /* ISO (0), Intr, Control, Bulk (3) */
+ unsigned char epnum; /* Endpoint number and transfer direction */
+ unsigned char devnum; /* Device address */
+ u16 busnum; /* 12: Bus number */
+ char flag_setup; /* 14: Same as text */
+ char flag_data; /* 15: Same as text; Binary zero is OK. */
+ s64 ts_sec; /* 16: gettimeofday */
+ s32 ts_usec; /* 24: gettimeofday */
+ int status; /* 28: */
+ unsigned int length; /* 32: Length of data (submitted or actual) */
+ unsigned int len_cap; /* 36: Delivered length */
+ unsigned char setup[8]; /* 40: Only for Control 'S' */
+}; /* 48 bytes total */
+
+These events can be received from a character device by reading with read(2),
+with an ioctl(2), or by accessing the buffer with mmap.
+
+The character device is usually called /dev/usbmonN, where N is the USB bus
+number. Number zero (/dev/usbmon0) is special and means "all buses".
+However, this feature is not implemented yet. Note that specific naming
+policy is set by your Linux distribution.
+
+If you create /dev/usbmon0 by hand, make sure that it is owned by root
+and has mode 0600. Otherwise, unpriviledged users will be able to snoop
+keyboard traffic.
+
+The following ioctl calls are available, with MON_IOC_MAGIC 0x92:
+
+ MON_IOCQ_URB_LEN, defined as _IO(MON_IOC_MAGIC, 1)
+
+This call returns the length of data in the next event. Note that majority of
+events contain no data, so if this call returns zero, it does not mean that
+no events are available.
+
+ MON_IOCG_STATS, defined as _IOR(MON_IOC_MAGIC, 3, struct mon_bin_stats)
+
+The argument is a pointer to the following structure:
+
+struct mon_bin_stats {
+ u32 queued;
+ u32 dropped;
+};
+
+The member "queued" refers to the number of events currently queued in the
+buffer (and not to the number of events processed since the last reset).
+
+The member "dropped" is the number of events lost since the last call
+to MON_IOCG_STATS.
+
+ MON_IOCT_RING_SIZE, defined as _IO(MON_IOC_MAGIC, 4)
+
+This call sets the buffer size. The argument is the size in bytes.
+The size may be rounded down to the next chunk (or page). If the requested
+size is out of [unspecified] bounds for this kernel, the call fails with
+-EINVAL.
+
+ MON_IOCQ_RING_SIZE, defined as _IO(MON_IOC_MAGIC, 5)
+
+This call returns the current size of the buffer in bytes.
+
+ MON_IOCX_GET, defined as _IOW(MON_IOC_MAGIC, 6, struct mon_get_arg)
+
+This call waits for events to arrive if none were in the kernel buffer,
+then returns the first event. Its argument is a pointer to the following
+structure:
+
+struct mon_get_arg {
+ struct usbmon_packet *hdr;
+ void *data;
+ size_t alloc; /* Length of data (can be zero) */
+};
+
+Before the call, hdr, data, and alloc should be filled. Upon return, the area
+pointed by hdr contains the next event structure, and the data buffer contains
+the data, if any. The event is removed from the kernel buffer.
+
+ MON_IOCX_MFETCH, defined as _IOWR(MON_IOC_MAGIC, 7, struct mon_mfetch_arg)
+
+This ioctl is primarily used when the application accesses the buffer
+with mmap(2). Its argument is a pointer to the following structure:
+
+struct mon_mfetch_arg {
+ uint32_t *offvec; /* Vector of events fetched */
+ uint32_t nfetch; /* Number of events to fetch (out: fetched) */
+ uint32_t nflush; /* Number of events to flush */
+};
+
+The ioctl operates in 3 stages.
+
+First, it removes and discards up to nflush events from the kernel buffer.
+The actual number of events discarded is returned in nflush.
+
+Second, it waits for an event to be present in the buffer, unless the pseudo-
+device is open with O_NONBLOCK.
+
+Third, it extracts up to nfetch offsets into the mmap buffer, and stores
+them into the offvec. The actual number of event offsets is stored into
+the nfetch.
+
+ MON_IOCH_MFLUSH, defined as _IO(MON_IOC_MAGIC, 8)
+
+This call removes a number of events from the kernel buffer. Its argument
+is the number of events to remove. If the buffer contains fewer events
+than requested, all events present are removed, and no error is reported.
+This works when no events are available too.
+
+ FIONBIO
+
+The ioctl FIONBIO may be implemented in the future, if there's a need.
+
+In addition to ioctl(2) and read(2), the special file of binary API can
+be polled with select(2) and poll(2). But lseek(2) does not work.
+
+* Memory-mapped access of the kernel buffer for the binary API
+
+The basic idea is simple:
+
+To prepare, map the buffer by getting the current size, then using mmap(2).
+Then, execute a loop similar to the one written in pseudo-code below:
+
+ struct mon_mfetch_arg fetch;
+ struct usbmon_packet *hdr;
+ int nflush = 0;
+ for (;;) {
+ fetch.offvec = vec; // Has N 32-bit words
+ fetch.nfetch = N; // Or less than N
+ fetch.nflush = nflush;
+ ioctl(fd, MON_IOCX_MFETCH, &fetch); // Process errors, too
+ nflush = fetch.nfetch; // This many packets to flush when done
+ for (i = 0; i < nflush; i++) {
+ hdr = (struct ubsmon_packet *) &mmap_area[vec[i]];
+ if (hdr->type == '@') // Filler packet
+ continue;
+ caddr_t data = &mmap_area[vec[i]] + 64;
+ process_packet(hdr, data);
+ }
+ }
+
+Thus, the main idea is to execute only one ioctl per N events.
+
+Although the buffer is circular, the returned headers and data do not cross
+the end of the buffer, so the above pseudo-code does not need any gathering.
--- /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 Pete Zaitcev (zaitcev@redhat.com)
+ */
+
+#include <linux/kernel.h>
+#include <linux/types.h>
+#include <linux/fs.h>
+#include <linux/cdev.h>
+#include <linux/usb.h>
+#include <linux/poll.h>
+#include <linux/compat.h>
+#include <linux/mm.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)
+#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)
+#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 */
+ unsigned char setup[SETUP_LEN]; /* Only for Control S-type */
+};
+
+/* per file statistic */
+struct mon_bin_stats {
+ u32 queued;
+ u32 dropped;
+};
+
+struct mon_bin_get {
+ struct mon_bin_hdr __user *hdr; /* Only 48 bytes, not 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
+
+/* 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 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.
+ * But it returns the new offset for repeated application.
+ */
+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 DMA fetch fails.
+ */
+static void mon_buff_area_shrink(struct mon_reader_bin *rp, unsigned int size)
+{
+
+ size = (size + PKT_ALIGN-1) & ~(PKT_ALIGN-1);
+ 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 (!usb_pipecontrol(urb->pipe) || ev_type != 'S')
+ return '-';
+
+ if (urb->transfer_flags & URB_NO_SETUP_DMA_MAP)
+ return mon_dmapeek(setupb, urb->setup_dma, SETUP_LEN);
+ if (urb->setup_packet == NULL)
+ return 'Z';
+
+ memcpy(setupb, urb->setup_packet, SETUP_LEN);
+ return 0;
+}
+
+static char mon_bin_get_data(const struct mon_reader_bin *rp,
+ unsigned int offset, struct urb *urb, unsigned int length)
+{
+
+ if (urb->transfer_flags & URB_NO_TRANSFER_DMA_MAP) {
+ mon_dmapeek_vec(rp, offset, urb->transfer_dma, length);
+ return 0;
+ }
+
+ if (urb->transfer_buffer == NULL)
+ return 'Z';
+
+ mon_copy_to_buff(rp, offset, urb->transfer_buffer, length);
+ return 0;
+}
+
+static void mon_bin_event(struct mon_reader_bin *rp, struct urb *urb,
+ char ev_type)
+{
+ unsigned long flags;
+ struct timeval ts;
+ unsigned int urb_length;
+ unsigned int offset;
+ unsigned int length;
+ 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 (length >= rp->b_size/5)
+ length = rp->b_size/5;
+
+ if (usb_pipein(urb->pipe)) {
+ if (ev_type == 'S') {
+ length = 0;
+ data_tag = '<';
+ }
+ } else {
+ if (ev_type == 'C') {
+ length = 0;
+ data_tag = '>';
+ }
+ }
+
+ if (rp->mmap_active)
+ offset = mon_buff_area_alloc_contiguous(rp, length + PKT_SIZE);
+ else
+ offset = mon_buff_area_alloc(rp, length + PKT_SIZE);
+ 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 = usb_pipetype(urb->pipe);
+ /* We use the fact that usb_pipein() returns 0x80 */
+ ep->epnum = usb_pipeendpoint(urb->pipe) | usb_pipein(urb->pipe);
+ ep->devnum = usb_pipedevice(urb->pipe);
+ ep->busnum = rp->r.m_bus->u_bus->busnum;
+ ep->id = (unsigned long) urb;
+ ep->ts_sec = ts.tv_sec;
+ ep->ts_usec = ts.tv_usec;
+ ep->status = urb->status;
+ ep->len_urb = urb_length;
+ ep->len_cap = length;
+
+ ep->flag_setup = mon_bin_get_setup(ep->setup, urb, ev_type);
+ if (length != 0) {
+ ep->flag_data = mon_bin_get_data(rp, offset, urb, length);
+ if (ep->flag_data != 0) { /* Yes, it's 0x00, not '0' */
+ ep->len_cap = 0;
+ mon_buff_area_shrink(rp, length);
+ }
+ } 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');
+}
+
+static void mon_bin_complete(void *data, struct urb *urb)
+{
+ struct mon_reader_bin *rp = data;
+ mon_bin_event(rp, urb, 'C');
+}
+
+static void mon_bin_error(void *data, struct urb *urb, int error)
+{
+ struct mon_reader_bin *rp = data;
+ unsigned long flags;
+ unsigned int offset;
+ struct mon_bin_hdr *ep;
+
+ 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 = usb_pipetype(urb->pipe);
+ /* We use the fact that usb_pipein() returns 0x80 */
+ ep->epnum = usb_pipeendpoint(urb->pipe) | usb_pipein(urb->pipe);
+ ep->devnum = usb_pipedevice(urb->pipe);
+ ep->busnum = rp->r.m_bus->u_bus->busnum;
+ ep->id = (unsigned long) urb;
+ 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 usb_bus *ubus;
+ 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 ((ubus = 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, 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, sizeof(struct mon_bin_hdr))) {
+ 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 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 < sizeof(struct mon_bin_hdr)) {
+ step_len = min(nbytes, sizeof(struct mon_bin_hdr) - 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 >= sizeof(struct mon_bin_hdr)) {
+ step_len = min(nbytes, (size_t)ep->len_cap);
+ offset = rp->b_out + PKT_SIZE;
+ offset += rp->b_read - sizeof(struct mon_bin_hdr);
+ 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 >= sizeof(struct mon_bin_hdr) + 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 int mon_bin_ioctl(struct inode *inode, 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, 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:
+ {
+ 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, getb.data, (unsigned int)getb.alloc);
+ }
+ break;
+
+#ifdef CONFIG_COMPAT
+ case MON_IOCX_GET32: {
+ 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), compat_ptr(getb.data32),
+ getb.alloc32);
+ }
+ break;
+#endif
+
+ 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;
+
+#ifdef CONFIG_COMPAT
+ 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;
+ ret = 0;
+ }
+ break;
+#endif
+
+ 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(rp->cnt_lost, &sp->dropped))
+ return -EFAULT;
+ if (put_user(nevents, &sp->queued))
+ return -EFAULT;
+
+ }
+ break;
+
+ default:
+ return -ENOTTY;
+ }
+
+ return ret;
+}
+
+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.
+ */
+struct page *mon_bin_vma_nopage(struct vm_area_struct *vma,
+ unsigned long address, int *type)
+{
+ struct mon_reader_bin *rp = vma->vm_private_data;
+ unsigned long offset, chunk_idx;
+ struct page *pageptr;
+
+ offset = (address - vma->vm_start) + (vma->vm_pgoff << PAGE_SHIFT);
+ if (offset >= rp->b_size)
+ return NOPAGE_SIGBUS;
+ chunk_idx = offset / CHUNK_SIZE;
+ pageptr = rp->b_vec[chunk_idx].pg;
+ get_page(pageptr);
+ if (type)
+ *type = VM_FAULT_MINOR;
+ return pageptr;
+}
+
+struct vm_operations_struct mon_bin_vm_ops = {
+ .open = mon_bin_vma_open,
+ .close = mon_bin_vma_close,
+ .nopage = mon_bin_vma_nopage,
+};
+
+int mon_bin_mmap(struct file *filp, struct vm_area_struct *vma)
+{
+ /* don't do anything here: "nopage" will set up page table entries */
+ vma->vm_ops = &mon_bin_vm_ops;
+ vma->vm_flags |= VM_RESERVED;
+ vma->vm_private_data = filp->private_data;
+ mon_bin_vma_open(vma);
+ return 0;
+}
+
+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,
+ .ioctl = mon_bin_ioctl,
+ .release = mon_bin_release,
+};
+
+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(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 __init mon_bin_init(void)
+{
+ int rc;
+
+ 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:
+ return rc;
+}
+
+void __exit mon_bin_exit(void)
+{
+ cdev_del(&mon_bin_cdev);
+ unregister_chrdev_region(mon_bin_dev0, MON_BIN_MAX_MINOR);
+}
projects / linux-drm-fsl-dcu.git / commitdiff