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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
commit | 2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch) | |
tree | 848558de17fb3008cdf4d861b01ac7781903ce39 /drivers/usb/mon/mon_bin.c | |
parent | Initial commit. (diff) | |
download | linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip |
Adding upstream version 6.1.76.upstream/6.1.76upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/usb/mon/mon_bin.c')
-rw-r--r-- | drivers/usb/mon/mon_bin.c | 1420 |
1 files changed, 1420 insertions, 0 deletions
diff --git a/drivers/usb/mon/mon_bin.c b/drivers/usb/mon/mon_bin.c new file mode 100644 index 000000000..35483217b --- /dev/null +++ b/drivers/usb/mon/mon_bin.c @@ -0,0 +1,1420 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * 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/sched/signal.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 <linux/time64.h> + +#include <linux/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; /* ktime_get_real_ts64 */ + s32 ts_usec; /* ktime_get_real_ts64 */ + 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 timespec64 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; + + ktime_get_real_ts64(&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_nsec / NSEC_PER_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 timespec64 ts; + unsigned long flags; + unsigned int offset; + struct mon_bin_hdr *ep; + + ktime_get_real_ts64(&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_nsec / NSEC_PER_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); + mbus = mon_bus_lookup(iminor(inode)); + if (mbus == 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: + mutex_lock(&rp->fetch_lock); + ret = rp->b_size; + mutex_unlock(&rp->fetch_lock); + 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); + vec = kcalloc(size / CHUNK_SIZE, sizeof(struct mon_pgmap), + GFP_KERNEL); + if (vec == 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); + if (rp->mmap_active) { + mon_free_buff(vec, size/CHUNK_SIZE); + kfree(vec); + ret = -EBUSY; + } else { + 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 __poll_t +mon_bin_poll(struct file *file, struct poll_table_struct *wait) +{ + struct mon_reader_bin *rp = file->private_data; + __poll_t 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 |= EPOLLIN | EPOLLRDNORM; /* 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; + unsigned long flags; + + spin_lock_irqsave(&rp->b_lock, flags); + rp->mmap_active++; + spin_unlock_irqrestore(&rp->b_lock, flags); +} + +static void mon_bin_vma_close(struct vm_area_struct *vma) +{ + unsigned long flags; + + struct mon_reader_bin *rp = vma->vm_private_data; + spin_lock_irqsave(&rp->b_lock, flags); + rp->mmap_active--; + spin_unlock_irqrestore(&rp->b_lock, flags); +} + +/* + * Map ring pages to user space. + */ +static vm_fault_t mon_bin_vma_fault(struct vm_fault *vmf) +{ + struct mon_reader_bin *rp = vmf->vma->vm_private_data; + unsigned long offset, chunk_idx; + struct page *pageptr; + unsigned long flags; + + spin_lock_irqsave(&rp->b_lock, flags); + offset = vmf->pgoff << PAGE_SHIFT; + if (offset >= rp->b_size) { + spin_unlock_irqrestore(&rp->b_lock, flags); + return VM_FAULT_SIGBUS; + } + chunk_idx = offset / CHUNK_SIZE; + pageptr = rp->b_vec[chunk_idx].pg; + get_page(pageptr); + vmf->page = pageptr; + spin_unlock_irqrestore(&rp->b_lock, flags); + 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; + + if (vma->vm_flags & VM_WRITE) + return -EPERM; + + vma->vm_flags &= ~VM_MAYWRITE; + 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); +} |