diff options
Diffstat (limited to 'drivers/usb/mon/mon_bin.c')
| -rw-r--r-- | drivers/usb/mon/mon_bin.c | 1172 | 
1 files changed, 1172 insertions, 0 deletions
diff --git a/drivers/usb/mon/mon_bin.c b/drivers/usb/mon/mon_bin.c new file mode 100644 index 00000000000..c01dfe60367 --- /dev/null +++ b/drivers/usb/mon/mon_bin.c @@ -0,0 +1,1172 @@ +/* + * 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); +}  |