diff options
Diffstat (limited to 'drivers/usb/atm/usbatm.c')
| -rw-r--r-- | drivers/usb/atm/usbatm.c | 1326 |
1 files changed, 1326 insertions, 0 deletions
diff --git a/drivers/usb/atm/usbatm.c b/drivers/usb/atm/usbatm.c new file mode 100644 index 000000000..56fe30d24 --- /dev/null +++ b/drivers/usb/atm/usbatm.c @@ -0,0 +1,1326 @@ +// SPDX-License-Identifier: GPL-2.0+ +/****************************************************************************** + * usbatm.c - Generic USB xDSL driver core + * + * Copyright (C) 2001, Alcatel + * Copyright (C) 2003, Duncan Sands, SolNegro, Josep Comas + * Copyright (C) 2004, David Woodhouse, Roman Kagan + ******************************************************************************/ + +/* + * Written by Johan Verrept, Duncan Sands (duncan.sands@free.fr) and David Woodhouse + * + * 1.7+: - See the check-in logs + * + * 1.6: - No longer opens a connection if the firmware is not loaded + * - Added support for the speedtouch 330 + * - Removed the limit on the number of devices + * - Module now autoloads on device plugin + * - Merged relevant parts of sarlib + * - Replaced the kernel thread with a tasklet + * - New packet transmission code + * - Changed proc file contents + * - Fixed all known SMP races + * - Many fixes and cleanups + * - Various fixes by Oliver Neukum (oliver@neukum.name) + * + * 1.5A: - Version for inclusion in 2.5 series kernel + * - Modifications by Richard Purdie (rpurdie@rpsys.net) + * - made compatible with kernel 2.5.6 onwards by changing + * usbatm_usb_send_data_context->urb to a pointer and adding code + * to alloc and free it + * - remove_wait_queue() added to usbatm_atm_processqueue_thread() + * + * 1.5: - fixed memory leak when atmsar_decode_aal5 returned NULL. + * (reported by stephen.robinson@zen.co.uk) + * + * 1.4: - changed the spin_lock() under interrupt to spin_lock_irqsave() + * - unlink all active send urbs of a vcc that is being closed. + * + * 1.3.1: - added the version number + * + * 1.3: - Added multiple send urb support + * - fixed memory leak and vcc->tx_inuse starvation bug + * when not enough memory left in vcc. + * + * 1.2: - Fixed race condition in usbatm_usb_send_data() + * 1.1: - Turned off packet debugging + * + */ + +#include "usbatm.h" + +#include <linux/uaccess.h> +#include <linux/crc32.h> +#include <linux/errno.h> +#include <linux/init.h> +#include <linux/interrupt.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/moduleparam.h> +#include <linux/netdevice.h> +#include <linux/proc_fs.h> +#include <linux/sched/signal.h> +#include <linux/signal.h> +#include <linux/slab.h> +#include <linux/stat.h> +#include <linux/timer.h> +#include <linux/wait.h> +#include <linux/kthread.h> +#include <linux/ratelimit.h> + +#ifdef VERBOSE_DEBUG +static int usbatm_print_packet(struct usbatm_data *instance, const unsigned char *data, int len); +#define PACKETDEBUG(arg...) usbatm_print_packet(arg) +#define vdbg(arg...) dev_dbg(arg) +#else +#define PACKETDEBUG(arg...) +#define vdbg(arg...) +#endif + +#define DRIVER_AUTHOR "Johan Verrept, Duncan Sands <duncan.sands@free.fr>" +#define DRIVER_DESC "Generic USB ATM/DSL I/O" + +static const char usbatm_driver_name[] = "usbatm"; + +#define UDSL_MAX_RCV_URBS 16 +#define UDSL_MAX_SND_URBS 16 +#define UDSL_MAX_BUF_SIZE 65536 +#define UDSL_DEFAULT_RCV_URBS 4 +#define UDSL_DEFAULT_SND_URBS 4 +#define UDSL_DEFAULT_RCV_BUF_SIZE 3392 /* 64 * ATM_CELL_SIZE */ +#define UDSL_DEFAULT_SND_BUF_SIZE 3392 /* 64 * ATM_CELL_SIZE */ + +#define ATM_CELL_HEADER (ATM_CELL_SIZE - ATM_CELL_PAYLOAD) + +#define THROTTLE_MSECS 100 /* delay to recover processing after urb submission fails */ + +static unsigned int num_rcv_urbs = UDSL_DEFAULT_RCV_URBS; +static unsigned int num_snd_urbs = UDSL_DEFAULT_SND_URBS; +static unsigned int rcv_buf_bytes = UDSL_DEFAULT_RCV_BUF_SIZE; +static unsigned int snd_buf_bytes = UDSL_DEFAULT_SND_BUF_SIZE; + +module_param(num_rcv_urbs, uint, S_IRUGO); +MODULE_PARM_DESC(num_rcv_urbs, + "Number of urbs used for reception (range: 0-" + __MODULE_STRING(UDSL_MAX_RCV_URBS) ", default: " + __MODULE_STRING(UDSL_DEFAULT_RCV_URBS) ")"); + +module_param(num_snd_urbs, uint, S_IRUGO); +MODULE_PARM_DESC(num_snd_urbs, + "Number of urbs used for transmission (range: 0-" + __MODULE_STRING(UDSL_MAX_SND_URBS) ", default: " + __MODULE_STRING(UDSL_DEFAULT_SND_URBS) ")"); + +module_param(rcv_buf_bytes, uint, S_IRUGO); +MODULE_PARM_DESC(rcv_buf_bytes, + "Size of the buffers used for reception, in bytes (range: 1-" + __MODULE_STRING(UDSL_MAX_BUF_SIZE) ", default: " + __MODULE_STRING(UDSL_DEFAULT_RCV_BUF_SIZE) ")"); + +module_param(snd_buf_bytes, uint, S_IRUGO); +MODULE_PARM_DESC(snd_buf_bytes, + "Size of the buffers used for transmission, in bytes (range: 1-" + __MODULE_STRING(UDSL_MAX_BUF_SIZE) ", default: " + __MODULE_STRING(UDSL_DEFAULT_SND_BUF_SIZE) ")"); + + +/* receive */ + +struct usbatm_vcc_data { + /* vpi/vci lookup */ + struct list_head list; + short vpi; + int vci; + struct atm_vcc *vcc; + + /* raw cell reassembly */ + struct sk_buff *sarb; +}; + + +/* send */ + +struct usbatm_control { + struct atm_skb_data atm; + u32 len; + u32 crc; +}; + +#define UDSL_SKB(x) ((struct usbatm_control *)(x)->cb) + + +/* ATM */ + +static void usbatm_atm_dev_close(struct atm_dev *atm_dev); +static int usbatm_atm_open(struct atm_vcc *vcc); +static void usbatm_atm_close(struct atm_vcc *vcc); +static int usbatm_atm_ioctl(struct atm_dev *atm_dev, unsigned int cmd, void __user *arg); +static int usbatm_atm_send(struct atm_vcc *vcc, struct sk_buff *skb); +static int usbatm_atm_proc_read(struct atm_dev *atm_dev, loff_t *pos, char *page); + +static const struct atmdev_ops usbatm_atm_devops = { + .dev_close = usbatm_atm_dev_close, + .open = usbatm_atm_open, + .close = usbatm_atm_close, + .ioctl = usbatm_atm_ioctl, + .send = usbatm_atm_send, + .proc_read = usbatm_atm_proc_read, + .owner = THIS_MODULE, +}; + + +/*********** +** misc ** +***********/ + +static inline unsigned int usbatm_pdu_length(unsigned int length) +{ + length += ATM_CELL_PAYLOAD - 1 + ATM_AAL5_TRAILER; + return length - length % ATM_CELL_PAYLOAD; +} + +static inline void usbatm_pop(struct atm_vcc *vcc, struct sk_buff *skb) +{ + if (vcc->pop) + vcc->pop(vcc, skb); + else + dev_kfree_skb_any(skb); +} + + +/*********** +** urbs ** +************/ + +static struct urb *usbatm_pop_urb(struct usbatm_channel *channel) +{ + struct urb *urb; + + spin_lock_irq(&channel->lock); + if (list_empty(&channel->list)) { + spin_unlock_irq(&channel->lock); + return NULL; + } + + urb = list_entry(channel->list.next, struct urb, urb_list); + list_del(&urb->urb_list); + spin_unlock_irq(&channel->lock); + + return urb; +} + +static int usbatm_submit_urb(struct urb *urb) +{ + struct usbatm_channel *channel = urb->context; + int ret; + + /* vdbg("%s: submitting urb 0x%p, size %u", + __func__, urb, urb->transfer_buffer_length); */ + + ret = usb_submit_urb(urb, GFP_ATOMIC); + if (ret) { + if (printk_ratelimit()) + atm_warn(channel->usbatm, "%s: urb 0x%p submission failed (%d)!\n", + __func__, urb, ret); + + /* consider all errors transient and return the buffer back to the queue */ + urb->status = -EAGAIN; + spin_lock_irq(&channel->lock); + + /* must add to the front when sending; doesn't matter when receiving */ + list_add(&urb->urb_list, &channel->list); + + spin_unlock_irq(&channel->lock); + + /* make sure the channel doesn't stall */ + mod_timer(&channel->delay, jiffies + msecs_to_jiffies(THROTTLE_MSECS)); + } + + return ret; +} + +static void usbatm_complete(struct urb *urb) +{ + struct usbatm_channel *channel = urb->context; + unsigned long flags; + int status = urb->status; + + /* vdbg("%s: urb 0x%p, status %d, actual_length %d", + __func__, urb, status, urb->actual_length); */ + + /* usually in_interrupt(), but not always */ + spin_lock_irqsave(&channel->lock, flags); + + /* must add to the back when receiving; doesn't matter when sending */ + list_add_tail(&urb->urb_list, &channel->list); + + spin_unlock_irqrestore(&channel->lock, flags); + + if (unlikely(status) && + (!(channel->usbatm->flags & UDSL_IGNORE_EILSEQ) || + status != -EILSEQ)) { + if (status == -ESHUTDOWN) + return; + + if (printk_ratelimit()) + atm_warn(channel->usbatm, "%s: urb 0x%p failed (%d)!\n", + __func__, urb, status); + /* throttle processing in case of an error */ + mod_timer(&channel->delay, jiffies + msecs_to_jiffies(THROTTLE_MSECS)); + } else + tasklet_schedule(&channel->tasklet); +} + + +/************* +** decode ** +*************/ + +static inline struct usbatm_vcc_data *usbatm_find_vcc(struct usbatm_data *instance, + short vpi, int vci) +{ + struct usbatm_vcc_data *vcc_data; + + list_for_each_entry(vcc_data, &instance->vcc_list, list) + if ((vcc_data->vci == vci) && (vcc_data->vpi == vpi)) + return vcc_data; + return NULL; +} + +static void usbatm_extract_one_cell(struct usbatm_data *instance, unsigned char *source) +{ + struct atm_vcc *vcc; + struct sk_buff *sarb; + short vpi = ((source[0] & 0x0f) << 4) | (source[1] >> 4); + int vci = ((source[1] & 0x0f) << 12) | (source[2] << 4) | (source[3] >> 4); + u8 pti = ((source[3] & 0xe) >> 1); + + if ((vci != instance->cached_vci) || (vpi != instance->cached_vpi)) { + instance->cached_vpi = vpi; + instance->cached_vci = vci; + + instance->cached_vcc = usbatm_find_vcc(instance, vpi, vci); + + if (!instance->cached_vcc) + atm_rldbg(instance, "%s: unknown vpi/vci (%hd/%d)!\n", __func__, vpi, vci); + } + + if (!instance->cached_vcc) + return; + + vcc = instance->cached_vcc->vcc; + + /* OAM F5 end-to-end */ + if (pti == ATM_PTI_E2EF5) { + if (printk_ratelimit()) + atm_warn(instance, "%s: OAM not supported (vpi %d, vci %d)!\n", + __func__, vpi, vci); + atomic_inc(&vcc->stats->rx_err); + return; + } + + sarb = instance->cached_vcc->sarb; + + if (sarb->tail + ATM_CELL_PAYLOAD > sarb->end) { + atm_rldbg(instance, "%s: buffer overrun (sarb->len %u, vcc: 0x%p)!\n", + __func__, sarb->len, vcc); + /* discard cells already received */ + skb_trim(sarb, 0); + } + + memcpy(skb_tail_pointer(sarb), source + ATM_CELL_HEADER, ATM_CELL_PAYLOAD); + __skb_put(sarb, ATM_CELL_PAYLOAD); + + if (pti & 1) { + struct sk_buff *skb; + unsigned int length; + unsigned int pdu_length; + + length = (source[ATM_CELL_SIZE - 6] << 8) + source[ATM_CELL_SIZE - 5]; + + /* guard against overflow */ + if (length > ATM_MAX_AAL5_PDU) { + atm_rldbg(instance, "%s: bogus length %u (vcc: 0x%p)!\n", + __func__, length, vcc); + atomic_inc(&vcc->stats->rx_err); + goto out; + } + + pdu_length = usbatm_pdu_length(length); + + if (sarb->len < pdu_length) { + atm_rldbg(instance, "%s: bogus pdu_length %u (sarb->len: %u, vcc: 0x%p)!\n", + __func__, pdu_length, sarb->len, vcc); + atomic_inc(&vcc->stats->rx_err); + goto out; + } + + if (crc32_be(~0, skb_tail_pointer(sarb) - pdu_length, pdu_length) != 0xc704dd7b) { + atm_rldbg(instance, "%s: packet failed crc check (vcc: 0x%p)!\n", + __func__, vcc); + atomic_inc(&vcc->stats->rx_err); + goto out; + } + + vdbg(&instance->usb_intf->dev, + "%s: got packet (length: %u, pdu_length: %u, vcc: 0x%p)", + __func__, length, pdu_length, vcc); + + skb = dev_alloc_skb(length); + if (!skb) { + if (printk_ratelimit()) + atm_err(instance, "%s: no memory for skb (length: %u)!\n", + __func__, length); + atomic_inc(&vcc->stats->rx_drop); + goto out; + } + + vdbg(&instance->usb_intf->dev, + "%s: allocated new sk_buff (skb: 0x%p, skb->truesize: %u)", + __func__, skb, skb->truesize); + + if (!atm_charge(vcc, skb->truesize)) { + atm_rldbg(instance, "%s: failed atm_charge (skb->truesize: %u)!\n", + __func__, skb->truesize); + dev_kfree_skb_any(skb); + goto out; /* atm_charge increments rx_drop */ + } + + skb_copy_to_linear_data(skb, + skb_tail_pointer(sarb) - pdu_length, + length); + __skb_put(skb, length); + + vdbg(&instance->usb_intf->dev, + "%s: sending skb 0x%p, skb->len %u, skb->truesize %u", + __func__, skb, skb->len, skb->truesize); + + PACKETDEBUG(instance, skb->data, skb->len); + + vcc->push(vcc, skb); + + atomic_inc(&vcc->stats->rx); + out: + skb_trim(sarb, 0); + } +} + +static void usbatm_extract_cells(struct usbatm_data *instance, + unsigned char *source, unsigned int avail_data) +{ + unsigned int stride = instance->rx_channel.stride; + unsigned int buf_usage = instance->buf_usage; + + /* extract cells from incoming data, taking into account that + * the length of avail data may not be a multiple of stride */ + + if (buf_usage > 0) { + /* we have a partially received atm cell */ + unsigned char *cell_buf = instance->cell_buf; + unsigned int space_left = stride - buf_usage; + + if (avail_data >= space_left) { + /* add new data and process cell */ + memcpy(cell_buf + buf_usage, source, space_left); + source += space_left; + avail_data -= space_left; + usbatm_extract_one_cell(instance, cell_buf); + instance->buf_usage = 0; + } else { + /* not enough data to fill the cell */ + memcpy(cell_buf + buf_usage, source, avail_data); + instance->buf_usage = buf_usage + avail_data; + return; + } + } + + for (; avail_data >= stride; avail_data -= stride, source += stride) + usbatm_extract_one_cell(instance, source); + + if (avail_data > 0) { + /* length was not a multiple of stride - + * save remaining data for next call */ + memcpy(instance->cell_buf, source, avail_data); + instance->buf_usage = avail_data; + } +} + + +/************* +** encode ** +*************/ + +static unsigned int usbatm_write_cells(struct usbatm_data *instance, + struct sk_buff *skb, + u8 *target, unsigned int avail_space) +{ + struct usbatm_control *ctrl = UDSL_SKB(skb); + struct atm_vcc *vcc = ctrl->atm.vcc; + unsigned int bytes_written; + unsigned int stride = instance->tx_channel.stride; + + for (bytes_written = 0; bytes_written < avail_space && ctrl->len; + bytes_written += stride, target += stride) { + unsigned int data_len = min_t(unsigned int, skb->len, ATM_CELL_PAYLOAD); + unsigned int left = ATM_CELL_PAYLOAD - data_len; + u8 *ptr = target; + + ptr[0] = vcc->vpi >> 4; + ptr[1] = (vcc->vpi << 4) | (vcc->vci >> 12); + ptr[2] = vcc->vci >> 4; + ptr[3] = vcc->vci << 4; + ptr[4] = 0xec; + ptr += ATM_CELL_HEADER; + + skb_copy_from_linear_data(skb, ptr, data_len); + ptr += data_len; + __skb_pull(skb, data_len); + + if (!left) + continue; + + memset(ptr, 0, left); + + if (left >= ATM_AAL5_TRAILER) { /* trailer will go in this cell */ + u8 *trailer = target + ATM_CELL_SIZE - ATM_AAL5_TRAILER; + /* trailer[0] = 0; UU = 0 */ + /* trailer[1] = 0; CPI = 0 */ + trailer[2] = ctrl->len >> 8; + trailer[3] = ctrl->len; + + ctrl->crc = ~crc32_be(ctrl->crc, ptr, left - 4); + + trailer[4] = ctrl->crc >> 24; + trailer[5] = ctrl->crc >> 16; + trailer[6] = ctrl->crc >> 8; + trailer[7] = ctrl->crc; + + target[3] |= 0x2; /* adjust PTI */ + + ctrl->len = 0; /* tag this skb finished */ + } else + ctrl->crc = crc32_be(ctrl->crc, ptr, left); + } + + return bytes_written; +} + + +/************** +** receive ** +**************/ + +static void usbatm_rx_process(struct tasklet_struct *t) +{ + struct usbatm_data *instance = from_tasklet(instance, t, + rx_channel.tasklet); + struct urb *urb; + + while ((urb = usbatm_pop_urb(&instance->rx_channel))) { + vdbg(&instance->usb_intf->dev, + "%s: processing urb 0x%p", __func__, urb); + + if (usb_pipeisoc(urb->pipe)) { + unsigned char *merge_start = NULL; + unsigned int merge_length = 0; + const unsigned int packet_size = instance->rx_channel.packet_size; + int i; + + for (i = 0; i < urb->number_of_packets; i++) { + if (!urb->iso_frame_desc[i].status) { + unsigned int actual_length = urb->iso_frame_desc[i].actual_length; + + if (!merge_length) + merge_start = (unsigned char *)urb->transfer_buffer + urb->iso_frame_desc[i].offset; + merge_length += actual_length; + if (merge_length && (actual_length < packet_size)) { + usbatm_extract_cells(instance, merge_start, merge_length); + merge_length = 0; + } + } else { + atm_rldbg(instance, "%s: status %d in frame %d!\n", __func__, urb->status, i); + if (merge_length) + usbatm_extract_cells(instance, merge_start, merge_length); + merge_length = 0; + instance->buf_usage = 0; + } + } + + if (merge_length) + usbatm_extract_cells(instance, merge_start, merge_length); + } else + if (!urb->status) + usbatm_extract_cells(instance, urb->transfer_buffer, urb->actual_length); + else + instance->buf_usage = 0; + + if (usbatm_submit_urb(urb)) + return; + } +} + + +/*********** +** send ** +***********/ + +static void usbatm_tx_process(struct tasklet_struct *t) +{ + struct usbatm_data *instance = from_tasklet(instance, t, + tx_channel.tasklet); + struct sk_buff *skb = instance->current_skb; + struct urb *urb = NULL; + const unsigned int buf_size = instance->tx_channel.buf_size; + unsigned int bytes_written = 0; + u8 *buffer = NULL; + + if (!skb) + skb = skb_dequeue(&instance->sndqueue); + + while (skb) { + if (!urb) { + urb = usbatm_pop_urb(&instance->tx_channel); + if (!urb) + break; /* no more senders */ + buffer = urb->transfer_buffer; + bytes_written = (urb->status == -EAGAIN) ? + urb->transfer_buffer_length : 0; + } + + bytes_written += usbatm_write_cells(instance, skb, + buffer + bytes_written, + buf_size - bytes_written); + + vdbg(&instance->usb_intf->dev, + "%s: wrote %u bytes from skb 0x%p to urb 0x%p", + __func__, bytes_written, skb, urb); + + if (!UDSL_SKB(skb)->len) { + struct atm_vcc *vcc = UDSL_SKB(skb)->atm.vcc; + + usbatm_pop(vcc, skb); + atomic_inc(&vcc->stats->tx); + + skb = skb_dequeue(&instance->sndqueue); + } + + if (bytes_written == buf_size || (!skb && bytes_written)) { + urb->transfer_buffer_length = bytes_written; + + if (usbatm_submit_urb(urb)) + break; + urb = NULL; + } + } + + instance->current_skb = skb; +} + +static void usbatm_cancel_send(struct usbatm_data *instance, + struct atm_vcc *vcc) +{ + struct sk_buff *skb, *n; + + spin_lock_irq(&instance->sndqueue.lock); + skb_queue_walk_safe(&instance->sndqueue, skb, n) { + if (UDSL_SKB(skb)->atm.vcc == vcc) { + atm_dbg(instance, "%s: popping skb 0x%p\n", __func__, skb); + __skb_unlink(skb, &instance->sndqueue); + usbatm_pop(vcc, skb); + } + } + spin_unlock_irq(&instance->sndqueue.lock); + + tasklet_disable(&instance->tx_channel.tasklet); + if ((skb = instance->current_skb) && (UDSL_SKB(skb)->atm.vcc == vcc)) { + atm_dbg(instance, "%s: popping current skb (0x%p)\n", __func__, skb); + instance->current_skb = NULL; + usbatm_pop(vcc, skb); + } + tasklet_enable(&instance->tx_channel.tasklet); +} + +static int usbatm_atm_send(struct atm_vcc *vcc, struct sk_buff *skb) +{ + struct usbatm_data *instance = vcc->dev->dev_data; + struct usbatm_control *ctrl = UDSL_SKB(skb); + int err; + + /* racy disconnection check - fine */ + if (!instance || instance->disconnected) { +#ifdef VERBOSE_DEBUG + printk_ratelimited(KERN_DEBUG "%s: %s!\n", __func__, instance ? "disconnected" : "NULL instance"); +#endif + err = -ENODEV; + goto fail; + } + + if (vcc->qos.aal != ATM_AAL5) { + atm_rldbg(instance, "%s: unsupported ATM type %d!\n", __func__, vcc->qos.aal); + err = -EINVAL; + goto fail; + } + + if (skb->len > ATM_MAX_AAL5_PDU) { + atm_rldbg(instance, "%s: packet too long (%d vs %d)!\n", + __func__, skb->len, ATM_MAX_AAL5_PDU); + err = -EINVAL; + goto fail; + } + + PACKETDEBUG(instance, skb->data, skb->len); + + /* initialize the control block */ + ctrl->atm.vcc = vcc; + ctrl->len = skb->len; + ctrl->crc = crc32_be(~0, skb->data, skb->len); + + skb_queue_tail(&instance->sndqueue, skb); + tasklet_schedule(&instance->tx_channel.tasklet); + + return 0; + + fail: + usbatm_pop(vcc, skb); + return err; +} + + +/******************** +** bean counting ** +********************/ + +static void usbatm_destroy_instance(struct kref *kref) +{ + struct usbatm_data *instance = container_of(kref, struct usbatm_data, refcount); + + tasklet_kill(&instance->rx_channel.tasklet); + tasklet_kill(&instance->tx_channel.tasklet); + usb_put_dev(instance->usb_dev); + kfree(instance); +} + +static void usbatm_get_instance(struct usbatm_data *instance) +{ + kref_get(&instance->refcount); +} + +static void usbatm_put_instance(struct usbatm_data *instance) +{ + kref_put(&instance->refcount, usbatm_destroy_instance); +} + + +/********** +** ATM ** +**********/ + +static void usbatm_atm_dev_close(struct atm_dev *atm_dev) +{ + struct usbatm_data *instance = atm_dev->dev_data; + + if (!instance) + return; + + atm_dev->dev_data = NULL; /* catch bugs */ + usbatm_put_instance(instance); /* taken in usbatm_atm_init */ +} + +static int usbatm_atm_proc_read(struct atm_dev *atm_dev, loff_t *pos, char *page) +{ + struct usbatm_data *instance = atm_dev->dev_data; + int left = *pos; + + if (!instance) + return -ENODEV; + + if (!left--) + return sprintf(page, "%s\n", instance->description); + + if (!left--) + return sprintf(page, "MAC: %pM\n", atm_dev->esi); + + if (!left--) + return sprintf(page, + "AAL5: tx %d ( %d err ), rx %d ( %d err, %d drop )\n", + atomic_read(&atm_dev->stats.aal5.tx), + atomic_read(&atm_dev->stats.aal5.tx_err), + atomic_read(&atm_dev->stats.aal5.rx), + atomic_read(&atm_dev->stats.aal5.rx_err), + atomic_read(&atm_dev->stats.aal5.rx_drop)); + + if (!left--) { + if (instance->disconnected) + return sprintf(page, "Disconnected\n"); + else + switch (atm_dev->signal) { + case ATM_PHY_SIG_FOUND: + return sprintf(page, "Line up\n"); + case ATM_PHY_SIG_LOST: + return sprintf(page, "Line down\n"); + default: + return sprintf(page, "Line state unknown\n"); + } + } + + return 0; +} + +static int usbatm_atm_open(struct atm_vcc *vcc) +{ + struct usbatm_data *instance = vcc->dev->dev_data; + struct usbatm_vcc_data *new = NULL; + int ret; + int vci = vcc->vci; + short vpi = vcc->vpi; + + if (!instance) + return -ENODEV; + + /* only support AAL5 */ + if ((vcc->qos.aal != ATM_AAL5)) { + atm_warn(instance, "%s: unsupported ATM type %d!\n", __func__, vcc->qos.aal); + return -EINVAL; + } + + /* sanity checks */ + if ((vcc->qos.rxtp.max_sdu < 0) || (vcc->qos.rxtp.max_sdu > ATM_MAX_AAL5_PDU)) { + atm_dbg(instance, "%s: max_sdu %d out of range!\n", __func__, vcc->qos.rxtp.max_sdu); + return -EINVAL; + } + + mutex_lock(&instance->serialize); /* vs self, usbatm_atm_close, usbatm_usb_disconnect */ + + if (instance->disconnected) { + atm_dbg(instance, "%s: disconnected!\n", __func__); + ret = -ENODEV; + goto fail; + } + + if (usbatm_find_vcc(instance, vpi, vci)) { + atm_dbg(instance, "%s: %hd/%d already in use!\n", __func__, vpi, vci); + ret = -EADDRINUSE; + goto fail; + } + + new = kzalloc(sizeof(struct usbatm_vcc_data), GFP_KERNEL); + if (!new) { + ret = -ENOMEM; + goto fail; + } + + new->vcc = vcc; + new->vpi = vpi; + new->vci = vci; + + new->sarb = alloc_skb(usbatm_pdu_length(vcc->qos.rxtp.max_sdu), GFP_KERNEL); + if (!new->sarb) { + atm_err(instance, "%s: no memory for SAR buffer!\n", __func__); + ret = -ENOMEM; + goto fail; + } + + vcc->dev_data = new; + + tasklet_disable(&instance->rx_channel.tasklet); + instance->cached_vcc = new; + instance->cached_vpi = vpi; + instance->cached_vci = vci; + list_add(&new->list, &instance->vcc_list); + tasklet_enable(&instance->rx_channel.tasklet); + + set_bit(ATM_VF_ADDR, &vcc->flags); + set_bit(ATM_VF_PARTIAL, &vcc->flags); + set_bit(ATM_VF_READY, &vcc->flags); + + mutex_unlock(&instance->serialize); + + atm_dbg(instance, "%s: allocated vcc data 0x%p\n", __func__, new); + + return 0; + +fail: + kfree(new); + mutex_unlock(&instance->serialize); + return ret; +} + +static void usbatm_atm_close(struct atm_vcc *vcc) +{ + struct usbatm_data *instance = vcc->dev->dev_data; + struct usbatm_vcc_data *vcc_data = vcc->dev_data; + + if (!instance || !vcc_data) + return; + + usbatm_cancel_send(instance, vcc); + + mutex_lock(&instance->serialize); /* vs self, usbatm_atm_open, usbatm_usb_disconnect */ + + tasklet_disable(&instance->rx_channel.tasklet); + if (instance->cached_vcc == vcc_data) { + instance->cached_vcc = NULL; + instance->cached_vpi = ATM_VPI_UNSPEC; + instance->cached_vci = ATM_VCI_UNSPEC; + } + list_del(&vcc_data->list); + tasklet_enable(&instance->rx_channel.tasklet); + + kfree_skb(vcc_data->sarb); + vcc_data->sarb = NULL; + + kfree(vcc_data); + vcc->dev_data = NULL; + + vcc->vpi = ATM_VPI_UNSPEC; + vcc->vci = ATM_VCI_UNSPEC; + clear_bit(ATM_VF_READY, &vcc->flags); + clear_bit(ATM_VF_PARTIAL, &vcc->flags); + clear_bit(ATM_VF_ADDR, &vcc->flags); + + mutex_unlock(&instance->serialize); +} + +static int usbatm_atm_ioctl(struct atm_dev *atm_dev, unsigned int cmd, + void __user *arg) +{ + struct usbatm_data *instance = atm_dev->dev_data; + + if (!instance || instance->disconnected) + return -ENODEV; + + switch (cmd) { + case ATM_QUERYLOOP: + return put_user(ATM_LM_NONE, (int __user *)arg) ? -EFAULT : 0; + default: + return -ENOIOCTLCMD; + } +} + +static int usbatm_atm_init(struct usbatm_data *instance) +{ + struct atm_dev *atm_dev; + int ret, i; + + /* ATM init. The ATM initialization scheme suffers from an intrinsic race + * condition: callbacks we register can be executed at once, before we have + * initialized the struct atm_dev. To protect against this, all callbacks + * abort if atm_dev->dev_data is NULL. */ + atm_dev = atm_dev_register(instance->driver_name, + &instance->usb_intf->dev, &usbatm_atm_devops, + -1, NULL); + if (!atm_dev) { + usb_err(instance, "%s: failed to register ATM device!\n", __func__); + return -1; + } + + instance->atm_dev = atm_dev; + + atm_dev->ci_range.vpi_bits = ATM_CI_MAX; + atm_dev->ci_range.vci_bits = ATM_CI_MAX; + atm_dev->signal = ATM_PHY_SIG_UNKNOWN; + + /* temp init ATM device, set to 128kbit */ + atm_dev->link_rate = 128 * 1000 / 424; + + if (instance->driver->atm_start && ((ret = instance->driver->atm_start(instance, atm_dev)) < 0)) { + atm_err(instance, "%s: atm_start failed: %d!\n", __func__, ret); + goto fail; + } + + usbatm_get_instance(instance); /* dropped in usbatm_atm_dev_close */ + + /* ready for ATM callbacks */ + mb(); + atm_dev->dev_data = instance; + + /* submit all rx URBs */ + for (i = 0; i < num_rcv_urbs; i++) + usbatm_submit_urb(instance->urbs[i]); + + return 0; + + fail: + instance->atm_dev = NULL; + atm_dev_deregister(atm_dev); /* usbatm_atm_dev_close will eventually be called */ + return ret; +} + + +/********** +** USB ** +**********/ + +static int usbatm_do_heavy_init(void *arg) +{ + struct usbatm_data *instance = arg; + int ret; + + allow_signal(SIGTERM); + complete(&instance->thread_started); + + ret = instance->driver->heavy_init(instance, instance->usb_intf); + + if (!ret) + ret = usbatm_atm_init(instance); + + mutex_lock(&instance->serialize); + instance->thread = NULL; + mutex_unlock(&instance->serialize); + + complete_and_exit(&instance->thread_exited, ret); +} + +static int usbatm_heavy_init(struct usbatm_data *instance) +{ + struct task_struct *t; + + t = kthread_create(usbatm_do_heavy_init, instance, "%s", + instance->driver->driver_name); + if (IS_ERR(t)) { + usb_err(instance, "%s: failed to create kernel_thread (%ld)!\n", + __func__, PTR_ERR(t)); + return PTR_ERR(t); + } + + instance->thread = t; + wake_up_process(t); + wait_for_completion(&instance->thread_started); + + return 0; +} + +static void usbatm_tasklet_schedule(struct timer_list *t) +{ + struct usbatm_channel *channel = from_timer(channel, t, delay); + + tasklet_schedule(&channel->tasklet); +} + +static void usbatm_init_channel(struct usbatm_channel *channel) +{ + spin_lock_init(&channel->lock); + INIT_LIST_HEAD(&channel->list); + timer_setup(&channel->delay, usbatm_tasklet_schedule, 0); +} + +int usbatm_usb_probe(struct usb_interface *intf, const struct usb_device_id *id, + struct usbatm_driver *driver) +{ + struct device *dev = &intf->dev; + struct usb_device *usb_dev = interface_to_usbdev(intf); + struct usbatm_data *instance; + char *buf; + int error = -ENOMEM; + int i, length; + unsigned int maxpacket, num_packets; + + /* instance init */ + instance = kzalloc(sizeof(*instance) + sizeof(struct urb *) * (num_rcv_urbs + num_snd_urbs), GFP_KERNEL); + if (!instance) + return -ENOMEM; + + /* public fields */ + + instance->driver = driver; + strlcpy(instance->driver_name, driver->driver_name, + sizeof(instance->driver_name)); + + instance->usb_dev = usb_dev; + instance->usb_intf = intf; + + buf = instance->description; + length = sizeof(instance->description); + + if ((i = usb_string(usb_dev, usb_dev->descriptor.iProduct, buf, length)) < 0) + goto bind; + + buf += i; + length -= i; + + i = scnprintf(buf, length, " ("); + buf += i; + length -= i; + + if (length <= 0 || (i = usb_make_path(usb_dev, buf, length)) < 0) + goto bind; + + buf += i; + length -= i; + + snprintf(buf, length, ")"); + + bind: + if (driver->bind && (error = driver->bind(instance, intf, id)) < 0) { + dev_err(dev, "%s: bind failed: %d!\n", __func__, error); + goto fail_free; + } + + /* private fields */ + + kref_init(&instance->refcount); /* dropped in usbatm_usb_disconnect */ + mutex_init(&instance->serialize); + + instance->thread = NULL; + init_completion(&instance->thread_started); + init_completion(&instance->thread_exited); + + INIT_LIST_HEAD(&instance->vcc_list); + skb_queue_head_init(&instance->sndqueue); + + usbatm_init_channel(&instance->rx_channel); + usbatm_init_channel(&instance->tx_channel); + tasklet_setup(&instance->rx_channel.tasklet, usbatm_rx_process); + tasklet_setup(&instance->tx_channel.tasklet, usbatm_tx_process); + instance->rx_channel.stride = ATM_CELL_SIZE + driver->rx_padding; + instance->tx_channel.stride = ATM_CELL_SIZE + driver->tx_padding; + instance->rx_channel.usbatm = instance->tx_channel.usbatm = instance; + + if ((instance->flags & UDSL_USE_ISOC) && driver->isoc_in) + instance->rx_channel.endpoint = usb_rcvisocpipe(usb_dev, driver->isoc_in); + else + instance->rx_channel.endpoint = usb_rcvbulkpipe(usb_dev, driver->bulk_in); + + instance->tx_channel.endpoint = usb_sndbulkpipe(usb_dev, driver->bulk_out); + + /* tx buffer size must be a positive multiple of the stride */ + instance->tx_channel.buf_size = max(instance->tx_channel.stride, + snd_buf_bytes - (snd_buf_bytes % instance->tx_channel.stride)); + + /* rx buffer size must be a positive multiple of the endpoint maxpacket */ + maxpacket = usb_maxpacket(usb_dev, instance->rx_channel.endpoint, 0); + + if ((maxpacket < 1) || (maxpacket > UDSL_MAX_BUF_SIZE)) { + dev_err(dev, "%s: invalid endpoint %02x!\n", __func__, + usb_pipeendpoint(instance->rx_channel.endpoint)); + error = -EINVAL; + goto fail_unbind; + } + + num_packets = max(1U, (rcv_buf_bytes + maxpacket / 2) / maxpacket); /* round */ + + if (num_packets * maxpacket > UDSL_MAX_BUF_SIZE) + num_packets--; + + instance->rx_channel.buf_size = num_packets * maxpacket; + instance->rx_channel.packet_size = maxpacket; + + for (i = 0; i < 2; i++) { + struct usbatm_channel *channel = i ? + &instance->tx_channel : &instance->rx_channel; + + dev_dbg(dev, "%s: using %d byte buffer for %s channel 0x%p\n", + __func__, channel->buf_size, i ? "tx" : "rx", channel); + } + + /* initialize urbs */ + + for (i = 0; i < num_rcv_urbs + num_snd_urbs; i++) { + u8 *buffer; + struct usbatm_channel *channel = i < num_rcv_urbs ? + &instance->rx_channel : &instance->tx_channel; + struct urb *urb; + unsigned int iso_packets = usb_pipeisoc(channel->endpoint) ? channel->buf_size / channel->packet_size : 0; + + urb = usb_alloc_urb(iso_packets, GFP_KERNEL); + if (!urb) { + error = -ENOMEM; + goto fail_unbind; + } + + instance->urbs[i] = urb; + + /* zero the tx padding to avoid leaking information */ + buffer = kzalloc(channel->buf_size, GFP_KERNEL); + if (!buffer) { + error = -ENOMEM; + goto fail_unbind; + } + + usb_fill_bulk_urb(urb, instance->usb_dev, channel->endpoint, + buffer, channel->buf_size, usbatm_complete, channel); + if (iso_packets) { + int j; + urb->interval = 1; + urb->transfer_flags = URB_ISO_ASAP; + urb->number_of_packets = iso_packets; + for (j = 0; j < iso_packets; j++) { + urb->iso_frame_desc[j].offset = channel->packet_size * j; + urb->iso_frame_desc[j].length = channel->packet_size; + } + } + + /* put all tx URBs on the list of spares */ + if (i >= num_rcv_urbs) + list_add_tail(&urb->urb_list, &channel->list); + + vdbg(&intf->dev, "%s: alloced buffer 0x%p buf size %u urb 0x%p", + __func__, urb->transfer_buffer, urb->transfer_buffer_length, urb); + } + + instance->cached_vpi = ATM_VPI_UNSPEC; + instance->cached_vci = ATM_VCI_UNSPEC; + instance->cell_buf = kmalloc(instance->rx_channel.stride, GFP_KERNEL); + + if (!instance->cell_buf) { + error = -ENOMEM; + goto fail_unbind; + } + + if (!(instance->flags & UDSL_SKIP_HEAVY_INIT) && driver->heavy_init) { + error = usbatm_heavy_init(instance); + } else { + complete(&instance->thread_exited); /* pretend that heavy_init was run */ + error = usbatm_atm_init(instance); + } + + if (error < 0) + goto fail_unbind; + + usb_get_dev(usb_dev); + usb_set_intfdata(intf, instance); + + return 0; + + fail_unbind: + if (instance->driver->unbind) + instance->driver->unbind(instance, intf); + fail_free: + kfree(instance->cell_buf); + + for (i = 0; i < num_rcv_urbs + num_snd_urbs; i++) { + if (instance->urbs[i]) + kfree(instance->urbs[i]->transfer_buffer); + usb_free_urb(instance->urbs[i]); + } + + kfree(instance); + + return error; +} +EXPORT_SYMBOL_GPL(usbatm_usb_probe); + +void usbatm_usb_disconnect(struct usb_interface *intf) +{ + struct device *dev = &intf->dev; + struct usbatm_data *instance = usb_get_intfdata(intf); + struct usbatm_vcc_data *vcc_data; + int i; + + if (!instance) { + dev_dbg(dev, "%s: NULL instance!\n", __func__); + return; + } + + usb_set_intfdata(intf, NULL); + + mutex_lock(&instance->serialize); + instance->disconnected = 1; + if (instance->thread != NULL) + send_sig(SIGTERM, instance->thread, 1); + mutex_unlock(&instance->serialize); + + wait_for_completion(&instance->thread_exited); + + mutex_lock(&instance->serialize); + list_for_each_entry(vcc_data, &instance->vcc_list, list) + vcc_release_async(vcc_data->vcc, -EPIPE); + mutex_unlock(&instance->serialize); + + tasklet_disable(&instance->rx_channel.tasklet); + tasklet_disable(&instance->tx_channel.tasklet); + + for (i = 0; i < num_rcv_urbs + num_snd_urbs; i++) + usb_kill_urb(instance->urbs[i]); + + del_timer_sync(&instance->rx_channel.delay); + del_timer_sync(&instance->tx_channel.delay); + + /* turn usbatm_[rt]x_process into something close to a no-op */ + /* no need to take the spinlock */ + INIT_LIST_HEAD(&instance->rx_channel.list); + INIT_LIST_HEAD(&instance->tx_channel.list); + + tasklet_enable(&instance->rx_channel.tasklet); + tasklet_enable(&instance->tx_channel.tasklet); + + if (instance->atm_dev && instance->driver->atm_stop) + instance->driver->atm_stop(instance, instance->atm_dev); + + if (instance->driver->unbind) + instance->driver->unbind(instance, intf); + + instance->driver_data = NULL; + + for (i = 0; i < num_rcv_urbs + num_snd_urbs; i++) { + kfree(instance->urbs[i]->transfer_buffer); + usb_free_urb(instance->urbs[i]); + } + + kfree(instance->cell_buf); + + /* ATM finalize */ + if (instance->atm_dev) { + atm_dev_deregister(instance->atm_dev); + instance->atm_dev = NULL; + } + + usbatm_put_instance(instance); /* taken in usbatm_usb_probe */ +} +EXPORT_SYMBOL_GPL(usbatm_usb_disconnect); + + +/*********** +** init ** +***********/ + +static int __init usbatm_usb_init(void) +{ + if (sizeof(struct usbatm_control) > sizeof_field(struct sk_buff, cb)) { + printk(KERN_ERR "%s unusable with this kernel!\n", usbatm_driver_name); + return -EIO; + } + + if ((num_rcv_urbs > UDSL_MAX_RCV_URBS) + || (num_snd_urbs > UDSL_MAX_SND_URBS) + || (rcv_buf_bytes < 1) + || (rcv_buf_bytes > UDSL_MAX_BUF_SIZE) + || (snd_buf_bytes < 1) + || (snd_buf_bytes > UDSL_MAX_BUF_SIZE)) + return -EINVAL; + + return 0; +} +module_init(usbatm_usb_init); + +static void __exit usbatm_usb_exit(void) +{ +} +module_exit(usbatm_usb_exit); + +MODULE_AUTHOR(DRIVER_AUTHOR); +MODULE_DESCRIPTION(DRIVER_DESC); +MODULE_LICENSE("GPL"); + +/************ +** debug ** +************/ + +#ifdef VERBOSE_DEBUG +static int usbatm_print_packet(struct usbatm_data *instance, + const unsigned char *data, int len) +{ + unsigned char buffer[256]; + int i = 0, j = 0; + + for (i = 0; i < len;) { + buffer[0] = '\0'; + sprintf(buffer, "%.3d :", i); + for (j = 0; (j < 16) && (i < len); j++, i++) + sprintf(buffer, "%s %2.2x", buffer, data[i]); + dev_dbg(&instance->usb_intf->dev, "%s", buffer); + } + return i; +} +#endif |