| Author | Tokens | Token Proportion | Commits | Commit Proportion |
|---|---|---|---|---|
| Peter Hurley | 12619 | 97.35% | 17 | 43.59% |
| Al Viro | 110 | 0.85% | 1 | 2.56% |
| Joe Perches | 78 | 0.60% | 1 | 2.56% |
| Tejun Heo | 35 | 0.27% | 1 | 2.56% |
| Dominique van den Broeck | 31 | 0.24% | 2 | 5.13% |
| Jiri Slaby | 21 | 0.16% | 4 | 10.26% |
| Stefan Richter | 20 | 0.15% | 1 | 2.56% |
| Kees Cook | 18 | 0.14% | 1 | 2.56% |
| Yangtao Li | 10 | 0.08% | 1 | 2.56% |
| Vladimirs Ambrosovs | 5 | 0.04% | 1 | 2.56% |
| Simon Chopin | 3 | 0.02% | 1 | 2.56% |
| Valentin Ilie | 3 | 0.02% | 1 | 2.56% |
| Shraddha Barke | 2 | 0.02% | 2 | 5.13% |
| Greg Kroah-Hartman | 2 | 0.02% | 2 | 5.13% |
| Christoph Hellwig | 2 | 0.02% | 1 | 2.56% |
| Monam Agarwal | 2 | 0.02% | 1 | 2.56% |
| Linus Torvalds | 1 | 0.01% | 1 | 2.56% |
| Total | 12962 | 39 |
// SPDX-License-Identifier: GPL-2.0+ /* * FireWire Serial driver * * Copyright (C) 2012 Peter Hurley <peter@hurleysoftware.com> */ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt #include <linux/sched.h> #include <linux/slab.h> #include <linux/device.h> #include <linux/mod_devicetable.h> #include <linux/rculist.h> #include <linux/workqueue.h> #include <linux/ratelimit.h> #include <linux/bug.h> #include <linux/uaccess.h> #include "fwserial.h" #define be32_to_u64(hi, lo) ((u64)be32_to_cpu(hi) << 32 | be32_to_cpu(lo)) #define LINUX_VENDOR_ID 0xd00d1eU /* same id used in card root directory */ #define FWSERIAL_VERSION 0x00e81cU /* must be unique within LINUX_VENDOR_ID */ /* configurable options */ static int num_ttys = 4; /* # of std ttys to create per fw_card */ /* - doubles as loopback port index */ static bool auto_connect = true; /* try to VIRT_CABLE to every peer */ static bool create_loop_dev = true; /* create a loopback device for each card */ module_param_named(ttys, num_ttys, int, 0644); module_param_named(auto, auto_connect, bool, 0644); module_param_named(loop, create_loop_dev, bool, 0644); /* * Threshold below which the tty is woken for writing * - should be equal to WAKEUP_CHARS in drivers/tty/n_tty.c because * even if the writer is woken, n_tty_poll() won't set EPOLLOUT until * our fifo is below this level */ #define WAKEUP_CHARS 256 /** * fwserial_list: list of every fw_serial created for each fw_card * See discussion in fwserial_probe. */ static LIST_HEAD(fwserial_list); static DEFINE_MUTEX(fwserial_list_mutex); /** * port_table: array of tty ports allocated to each fw_card * * tty ports are allocated during probe when an fw_serial is first * created for a given fw_card. Ports are allocated in a contiguous block, * each block consisting of 'num_ports' ports. */ static struct fwtty_port *port_table[MAX_TOTAL_PORTS]; static DEFINE_MUTEX(port_table_lock); static bool port_table_corrupt; #define FWTTY_INVALID_INDEX MAX_TOTAL_PORTS #define loop_idx(port) (((port)->index) / num_ports) #define table_idx(loop) ((loop) * num_ports + num_ttys) /* total # of tty ports created per fw_card */ static int num_ports; /* slab used as pool for struct fwtty_transactions */ static struct kmem_cache *fwtty_txn_cache; struct tty_driver *fwtty_driver; static struct tty_driver *fwloop_driver; static struct dentry *fwserial_debugfs; struct fwtty_transaction; typedef void (*fwtty_transaction_cb)(struct fw_card *card, int rcode, void *data, size_t length, struct fwtty_transaction *txn); struct fwtty_transaction { struct fw_transaction fw_txn; fwtty_transaction_cb callback; struct fwtty_port *port; union { struct dma_pending dma_pended; }; }; #define to_device(a, b) (a->b) #define fwtty_err(p, fmt, ...) \ dev_err(to_device(p, device), fmt, ##__VA_ARGS__) #define fwtty_info(p, fmt, ...) \ dev_info(to_device(p, device), fmt, ##__VA_ARGS__) #define fwtty_notice(p, fmt, ...) \ dev_notice(to_device(p, device), fmt, ##__VA_ARGS__) #define fwtty_dbg(p, fmt, ...) \ dev_dbg(to_device(p, device), "%s: " fmt, __func__, ##__VA_ARGS__) #define fwtty_err_ratelimited(p, fmt, ...) \ dev_err_ratelimited(to_device(p, device), fmt, ##__VA_ARGS__) #ifdef DEBUG static inline void debug_short_write(struct fwtty_port *port, int c, int n) { int avail; if (n < c) { spin_lock_bh(&port->lock); avail = dma_fifo_avail(&port->tx_fifo); spin_unlock_bh(&port->lock); fwtty_dbg(port, "short write: avail:%d req:%d wrote:%d\n", avail, c, n); } } #else #define debug_short_write(port, c, n) #endif static struct fwtty_peer *__fwserial_peer_by_node_id(struct fw_card *card, int generation, int id); #ifdef FWTTY_PROFILING static void fwtty_profile_fifo(struct fwtty_port *port, unsigned int *stat) { spin_lock_bh(&port->lock); fwtty_profile_data(stat, dma_fifo_avail(&port->tx_fifo)); spin_unlock_bh(&port->lock); } static void fwtty_dump_profile(struct seq_file *m, struct stats *stats) { /* for each stat, print sum of 0 to 2^k, then individually */ int k = 4; unsigned int sum; int j; char t[10]; snprintf(t, 10, "< %d", 1 << k); seq_printf(m, "\n%14s %6s", " ", t); for (j = k + 1; j < DISTRIBUTION_MAX_INDEX; ++j) seq_printf(m, "%6d", 1 << j); ++k; for (j = 0, sum = 0; j <= k; ++j) sum += stats->reads[j]; seq_printf(m, "\n%14s: %6d", "reads", sum); for (j = k + 1; j <= DISTRIBUTION_MAX_INDEX; ++j) seq_printf(m, "%6d", stats->reads[j]); for (j = 0, sum = 0; j <= k; ++j) sum += stats->writes[j]; seq_printf(m, "\n%14s: %6d", "writes", sum); for (j = k + 1; j <= DISTRIBUTION_MAX_INDEX; ++j) seq_printf(m, "%6d", stats->writes[j]); for (j = 0, sum = 0; j <= k; ++j) sum += stats->txns[j]; seq_printf(m, "\n%14s: %6d", "txns", sum); for (j = k + 1; j <= DISTRIBUTION_MAX_INDEX; ++j) seq_printf(m, "%6d", stats->txns[j]); for (j = 0, sum = 0; j <= k; ++j) sum += stats->unthrottle[j]; seq_printf(m, "\n%14s: %6d", "avail @ unthr", sum); for (j = k + 1; j <= DISTRIBUTION_MAX_INDEX; ++j) seq_printf(m, "%6d", stats->unthrottle[j]); } #else #define fwtty_profile_fifo(port, stat) #define fwtty_dump_profile(m, stats) #endif /* * Returns the max receive packet size for the given node * Devices which are OHCI v1.0/ v1.1/ v1.2-draft or RFC 2734 compliant * are required by specification to support max_rec of 8 (512 bytes) or more. */ static inline int device_max_receive(struct fw_device *fw_device) { /* see IEEE 1394-2008 table 8-8 */ return min(2 << fw_device->max_rec, 4096); } static void fwtty_log_tx_error(struct fwtty_port *port, int rcode) { switch (rcode) { case RCODE_SEND_ERROR: fwtty_err_ratelimited(port, "card busy\n"); break; case RCODE_ADDRESS_ERROR: fwtty_err_ratelimited(port, "bad unit addr or write length\n"); break; case RCODE_DATA_ERROR: fwtty_err_ratelimited(port, "failed rx\n"); break; case RCODE_NO_ACK: fwtty_err_ratelimited(port, "missing ack\n"); break; case RCODE_BUSY: fwtty_err_ratelimited(port, "remote busy\n"); break; default: fwtty_err_ratelimited(port, "failed tx: %d\n", rcode); } } static void fwtty_common_callback(struct fw_card *card, int rcode, void *payload, size_t len, void *cb_data) { struct fwtty_transaction *txn = cb_data; struct fwtty_port *port = txn->port; if (port && rcode != RCODE_COMPLETE) fwtty_log_tx_error(port, rcode); if (txn->callback) txn->callback(card, rcode, payload, len, txn); kmem_cache_free(fwtty_txn_cache, txn); } static int fwtty_send_data_async(struct fwtty_peer *peer, int tcode, unsigned long long addr, void *payload, size_t len, fwtty_transaction_cb callback, struct fwtty_port *port) { struct fwtty_transaction *txn; int generation; txn = kmem_cache_alloc(fwtty_txn_cache, GFP_ATOMIC); if (!txn) return -ENOMEM; txn->callback = callback; txn->port = port; generation = peer->generation; smp_rmb(); fw_send_request(peer->serial->card, &txn->fw_txn, tcode, peer->node_id, generation, peer->speed, addr, payload, len, fwtty_common_callback, txn); return 0; } static void fwtty_send_txn_async(struct fwtty_peer *peer, struct fwtty_transaction *txn, int tcode, unsigned long long addr, void *payload, size_t len, fwtty_transaction_cb callback, struct fwtty_port *port) { int generation; txn->callback = callback; txn->port = port; generation = peer->generation; smp_rmb(); fw_send_request(peer->serial->card, &txn->fw_txn, tcode, peer->node_id, generation, peer->speed, addr, payload, len, fwtty_common_callback, txn); } static void __fwtty_restart_tx(struct fwtty_port *port) { int len, avail; len = dma_fifo_out_level(&port->tx_fifo); if (len) schedule_delayed_work(&port->drain, 0); avail = dma_fifo_avail(&port->tx_fifo); fwtty_dbg(port, "fifo len: %d avail: %d\n", len, avail); } static void fwtty_restart_tx(struct fwtty_port *port) { spin_lock_bh(&port->lock); __fwtty_restart_tx(port); spin_unlock_bh(&port->lock); } /** * fwtty_update_port_status - decodes & dispatches line status changes * * Note: in loopback, the port->lock is being held. Only use functions that * don't attempt to reclaim the port->lock. */ static void fwtty_update_port_status(struct fwtty_port *port, unsigned int status) { unsigned int delta; struct tty_struct *tty; /* simulated LSR/MSR status from remote */ status &= ~MCTRL_MASK; delta = (port->mstatus ^ status) & ~MCTRL_MASK; delta &= ~(status & TIOCM_RNG); port->mstatus = status; if (delta & TIOCM_RNG) ++port->icount.rng; if (delta & TIOCM_DSR) ++port->icount.dsr; if (delta & TIOCM_CAR) ++port->icount.dcd; if (delta & TIOCM_CTS) ++port->icount.cts; fwtty_dbg(port, "status: %x delta: %x\n", status, delta); if (delta & TIOCM_CAR) { tty = tty_port_tty_get(&port->port); if (tty && !C_CLOCAL(tty)) { if (status & TIOCM_CAR) wake_up_interruptible(&port->port.open_wait); else schedule_work(&port->hangup); } tty_kref_put(tty); } if (delta & TIOCM_CTS) { tty = tty_port_tty_get(&port->port); if (tty && C_CRTSCTS(tty)) { if (tty->hw_stopped) { if (status & TIOCM_CTS) { tty->hw_stopped = 0; if (port->loopback) __fwtty_restart_tx(port); else fwtty_restart_tx(port); } } else { if (~status & TIOCM_CTS) tty->hw_stopped = 1; } } tty_kref_put(tty); } else if (delta & OOB_TX_THROTTLE) { tty = tty_port_tty_get(&port->port); if (tty) { if (tty->hw_stopped) { if (~status & OOB_TX_THROTTLE) { tty->hw_stopped = 0; if (port->loopback) __fwtty_restart_tx(port); else fwtty_restart_tx(port); } } else { if (status & OOB_TX_THROTTLE) tty->hw_stopped = 1; } } tty_kref_put(tty); } if (delta & (UART_LSR_BI << 24)) { if (status & (UART_LSR_BI << 24)) { port->break_last = jiffies; schedule_delayed_work(&port->emit_breaks, 0); } else { /* run emit_breaks one last time (if pending) */ mod_delayed_work(system_wq, &port->emit_breaks, 0); } } if (delta & (TIOCM_DSR | TIOCM_CAR | TIOCM_CTS | TIOCM_RNG)) wake_up_interruptible(&port->port.delta_msr_wait); } /** * __fwtty_port_line_status - generate 'line status' for indicated port * * This function returns a remote 'MSR' state based on the local 'MCR' state, * as if a null modem cable was attached. The actual status is a mangling * of TIOCM_* bits suitable for sending to a peer's status_addr. * * Note: caller must be holding port lock */ static unsigned int __fwtty_port_line_status(struct fwtty_port *port) { unsigned int status = 0; /* TODO: add module param to tie RNG to DTR as well */ if (port->mctrl & TIOCM_DTR) status |= TIOCM_DSR | TIOCM_CAR; if (port->mctrl & TIOCM_RTS) status |= TIOCM_CTS; if (port->mctrl & OOB_RX_THROTTLE) status |= OOB_TX_THROTTLE; /* emulate BRK as add'l line status */ if (port->break_ctl) status |= UART_LSR_BI << 24; return status; } /** * __fwtty_write_port_status - send the port line status to peer * * Note: caller must be holding the port lock. */ static int __fwtty_write_port_status(struct fwtty_port *port) { struct fwtty_peer *peer; int err = -ENOENT; unsigned int status = __fwtty_port_line_status(port); rcu_read_lock(); peer = rcu_dereference(port->peer); if (peer) { err = fwtty_send_data_async(peer, TCODE_WRITE_QUADLET_REQUEST, peer->status_addr, &status, sizeof(status), NULL, port); } rcu_read_unlock(); return err; } /** * fwtty_write_port_status - same as above but locked by port lock */ static int fwtty_write_port_status(struct fwtty_port *port) { int err; spin_lock_bh(&port->lock); err = __fwtty_write_port_status(port); spin_unlock_bh(&port->lock); return err; } static void fwtty_throttle_port(struct fwtty_port *port) { struct tty_struct *tty; unsigned int old; tty = tty_port_tty_get(&port->port); if (!tty) return; spin_lock_bh(&port->lock); old = port->mctrl; port->mctrl |= OOB_RX_THROTTLE; if (C_CRTSCTS(tty)) port->mctrl &= ~TIOCM_RTS; if (~old & OOB_RX_THROTTLE) __fwtty_write_port_status(port); spin_unlock_bh(&port->lock); tty_kref_put(tty); } /** * fwtty_do_hangup - wait for ldisc to deliver all pending rx; only then hangup * * When the remote has finished tx, and all in-flight rx has been received and * and pushed to the flip buffer, the remote may close its device. This will * drop DTR on the remote which will drop carrier here. Typically, the tty is * hung up when carrier is dropped or lost. * * However, there is a race between the hang up and the line discipline * delivering its data to the reader. A hangup will cause the ldisc to flush * (ie., clear) the read buffer and flip buffer. Because of firewire's * relatively high throughput, the ldisc frequently lags well behind the driver, * resulting in lost data (which has already been received and written to * the flip buffer) when the remote closes its end. * * Unfortunately, since the flip buffer offers no direct method for determining * if it holds data, ensuring the ldisc has delivered all data is problematic. */ /* FIXME: drop this workaround when __tty_hangup waits for ldisc completion */ static void fwtty_do_hangup(struct work_struct *work) { struct fwtty_port *port = to_port(work, hangup); struct tty_struct *tty; schedule_timeout_uninterruptible(msecs_to_jiffies(50)); tty = tty_port_tty_get(&port->port); if (tty) tty_vhangup(tty); tty_kref_put(tty); } static void fwtty_emit_breaks(struct work_struct *work) { struct fwtty_port *port = to_port(to_delayed_work(work), emit_breaks); static const char buf[16]; unsigned long now = jiffies; unsigned long elapsed = now - port->break_last; int n, t, c, brk = 0; /* generate breaks at the line rate (but at least 1) */ n = (elapsed * port->cps) / HZ + 1; port->break_last = now; fwtty_dbg(port, "sending %d brks\n", n); while (n) { t = min(n, 16); c = tty_insert_flip_string_fixed_flag(&port->port, buf, TTY_BREAK, t); n -= c; brk += c; if (c < t) break; } tty_flip_buffer_push(&port->port); if (port->mstatus & (UART_LSR_BI << 24)) schedule_delayed_work(&port->emit_breaks, FREQ_BREAKS); port->icount.brk += brk; } static int fwtty_rx(struct fwtty_port *port, unsigned char *data, size_t len) { int c, n = len; unsigned int lsr; int err = 0; fwtty_dbg(port, "%d\n", n); fwtty_profile_data(port->stats.reads, n); if (port->write_only) { n = 0; goto out; } /* disregard break status; breaks are generated by emit_breaks work */ lsr = (port->mstatus >> 24) & ~UART_LSR_BI; if (port->overrun) lsr |= UART_LSR_OE; if (lsr & UART_LSR_OE) ++port->icount.overrun; lsr &= port->status_mask; if (lsr & ~port->ignore_mask & UART_LSR_OE) { if (!tty_insert_flip_char(&port->port, 0, TTY_OVERRUN)) { err = -EIO; goto out; } } port->overrun = false; if (lsr & port->ignore_mask & ~UART_LSR_OE) { /* TODO: don't drop SAK and Magic SysRq here */ n = 0; goto out; } c = tty_insert_flip_string_fixed_flag(&port->port, data, TTY_NORMAL, n); if (c > 0) tty_flip_buffer_push(&port->port); n -= c; if (n) { port->overrun = true; err = -EIO; fwtty_err_ratelimited(port, "flip buffer overrun\n"); } else { /* throttle the sender if remaining flip buffer space has * reached high watermark to avoid losing data which may be * in-flight. Since the AR request context is 32k, that much * data may have _already_ been acked. */ if (tty_buffer_space_avail(&port->port) < HIGH_WATERMARK) fwtty_throttle_port(port); } out: port->icount.rx += len; port->stats.lost += n; return err; } /** * fwtty_port_handler - bus address handler for port reads/writes * @parameters: fw_address_callback_t as specified by firewire core interface * * This handler is responsible for handling inbound read/write dma from remotes. */ static void fwtty_port_handler(struct fw_card *card, struct fw_request *request, int tcode, int destination, int source, int generation, unsigned long long addr, void *data, size_t len, void *callback_data) { struct fwtty_port *port = callback_data; struct fwtty_peer *peer; int err; int rcode; /* Only accept rx from the peer virtual-cabled to this port */ rcu_read_lock(); peer = __fwserial_peer_by_node_id(card, generation, source); rcu_read_unlock(); if (!peer || peer != rcu_access_pointer(port->peer)) { rcode = RCODE_ADDRESS_ERROR; fwtty_err_ratelimited(port, "ignoring unauthenticated data\n"); goto respond; } switch (tcode) { case TCODE_WRITE_QUADLET_REQUEST: if (addr != port->rx_handler.offset || len != 4) { rcode = RCODE_ADDRESS_ERROR; } else { fwtty_update_port_status(port, *(unsigned int *)data); rcode = RCODE_COMPLETE; } break; case TCODE_WRITE_BLOCK_REQUEST: if (addr != port->rx_handler.offset + 4 || len > port->rx_handler.length - 4) { rcode = RCODE_ADDRESS_ERROR; } else { err = fwtty_rx(port, data, len); switch (err) { case 0: rcode = RCODE_COMPLETE; break; case -EIO: rcode = RCODE_DATA_ERROR; break; default: rcode = RCODE_CONFLICT_ERROR; break; } } break; default: rcode = RCODE_TYPE_ERROR; } respond: fw_send_response(card, request, rcode); } /** * fwtty_tx_complete - callback for tx dma * @data: ignored, has no meaning for write txns * @length: ignored, has no meaning for write txns * * The writer must be woken here if the fifo has been emptied because it * may have slept if chars_in_buffer was != 0 */ static void fwtty_tx_complete(struct fw_card *card, int rcode, void *data, size_t length, struct fwtty_transaction *txn) { struct fwtty_port *port = txn->port; int len; fwtty_dbg(port, "rcode: %d\n", rcode); switch (rcode) { case RCODE_COMPLETE: spin_lock_bh(&port->lock); dma_fifo_out_complete(&port->tx_fifo, &txn->dma_pended); len = dma_fifo_level(&port->tx_fifo); spin_unlock_bh(&port->lock); port->icount.tx += txn->dma_pended.len; break; default: /* TODO: implement retries */ spin_lock_bh(&port->lock); dma_fifo_out_complete(&port->tx_fifo, &txn->dma_pended); len = dma_fifo_level(&port->tx_fifo); spin_unlock_bh(&port->lock); port->stats.dropped += txn->dma_pended.len; } if (len < WAKEUP_CHARS) tty_port_tty_wakeup(&port->port); } static int fwtty_tx(struct fwtty_port *port, bool drain) { struct fwtty_peer *peer; struct fwtty_transaction *txn; struct tty_struct *tty; int n, len; tty = tty_port_tty_get(&port->port); if (!tty) return -ENOENT; rcu_read_lock(); peer = rcu_dereference(port->peer); if (!peer) { n = -EIO; goto out; } if (test_and_set_bit(IN_TX, &port->flags)) { n = -EALREADY; goto out; } /* try to write as many dma transactions out as possible */ n = -EAGAIN; while (!tty->stopped && !tty->hw_stopped && !test_bit(STOP_TX, &port->flags)) { txn = kmem_cache_alloc(fwtty_txn_cache, GFP_ATOMIC); if (!txn) { n = -ENOMEM; break; } spin_lock_bh(&port->lock); n = dma_fifo_out_pend(&port->tx_fifo, &txn->dma_pended); spin_unlock_bh(&port->lock); fwtty_dbg(port, "out: %u rem: %d\n", txn->dma_pended.len, n); if (n < 0) { kmem_cache_free(fwtty_txn_cache, txn); if (n == -EAGAIN) { ++port->stats.tx_stall; } else if (n == -ENODATA) { fwtty_profile_data(port->stats.txns, 0); } else { ++port->stats.fifo_errs; fwtty_err_ratelimited(port, "fifo err: %d\n", n); } break; } fwtty_profile_data(port->stats.txns, txn->dma_pended.len); fwtty_send_txn_async(peer, txn, TCODE_WRITE_BLOCK_REQUEST, peer->fifo_addr, txn->dma_pended.data, txn->dma_pended.len, fwtty_tx_complete, port); ++port->stats.sent; /* * Stop tx if the 'last view' of the fifo is empty or if * this is the writer and there's not enough data to bother */ if (n == 0 || (!drain && n < WRITER_MINIMUM)) break; } if (n >= 0 || n == -EAGAIN || n == -ENOMEM || n == -ENODATA) { spin_lock_bh(&port->lock); len = dma_fifo_out_level(&port->tx_fifo); if (len) { unsigned long delay = (n == -ENOMEM) ? HZ : 1; schedule_delayed_work(&port->drain, delay); } len = dma_fifo_level(&port->tx_fifo); spin_unlock_bh(&port->lock); /* wakeup the writer */ if (drain && len < WAKEUP_CHARS) tty_wakeup(tty); } clear_bit(IN_TX, &port->flags); wake_up_interruptible(&port->wait_tx); out: rcu_read_unlock(); tty_kref_put(tty); return n; } static void fwtty_drain_tx(struct work_struct *work) { struct fwtty_port *port = to_port(to_delayed_work(work), drain); fwtty_tx(port, true); } static void fwtty_write_xchar(struct fwtty_port *port, char ch) { struct fwtty_peer *peer; ++port->stats.xchars; fwtty_dbg(port, "%02x\n", ch); rcu_read_lock(); peer = rcu_dereference(port->peer); if (peer) { fwtty_send_data_async(peer, TCODE_WRITE_BLOCK_REQUEST, peer->fifo_addr, &ch, sizeof(ch), NULL, port); } rcu_read_unlock(); } static struct fwtty_port *fwtty_port_get(unsigned int index) { struct fwtty_port *port; if (index >= MAX_TOTAL_PORTS) return NULL; mutex_lock(&port_table_lock); port = port_table[index]; if (port) kref_get(&port->serial->kref); mutex_unlock(&port_table_lock); return port; } static int fwtty_ports_add(struct fw_serial *serial) { int err = -EBUSY; int i, j; if (port_table_corrupt) return err; mutex_lock(&port_table_lock); for (i = 0; i + num_ports <= MAX_TOTAL_PORTS; i += num_ports) { if (!port_table[i]) { for (j = 0; j < num_ports; ++i, ++j) { serial->ports[j]->index = i; port_table[i] = serial->ports[j]; } err = 0; break; } } mutex_unlock(&port_table_lock); return err; } static void fwserial_destroy(struct kref *kref) { struct fw_serial *serial = to_serial(kref, kref); struct fwtty_port **ports = serial->ports; int j, i = ports[0]->index; synchronize_rcu(); mutex_lock(&port_table_lock); for (j = 0; j < num_ports; ++i, ++j) { port_table_corrupt |= port_table[i] != ports[j]; WARN_ONCE(port_table_corrupt, "port_table[%d]: %p != ports[%d]: %p", i, port_table[i], j, ports[j]); port_table[i] = NULL; } mutex_unlock(&port_table_lock); for (j = 0; j < num_ports; ++j) { fw_core_remove_address_handler(&ports[j]->rx_handler); tty_port_destroy(&ports[j]->port); kfree(ports[j]); } kfree(serial); } static void fwtty_port_put(struct fwtty_port *port) { kref_put(&port->serial->kref, fwserial_destroy); } static void fwtty_port_dtr_rts(struct tty_port *tty_port, int on) { struct fwtty_port *port = to_port(tty_port, port); fwtty_dbg(port, "on/off: %d\n", on); spin_lock_bh(&port->lock); /* Don't change carrier state if this is a console */ if (!port->port.console) { if (on) port->mctrl |= TIOCM_DTR | TIOCM_RTS; else port->mctrl &= ~(TIOCM_DTR | TIOCM_RTS); } __fwtty_write_port_status(port); spin_unlock_bh(&port->lock); } /** * fwtty_port_carrier_raised: required tty_port operation * * This port operation is polled after a tty has been opened and is waiting for * carrier detect -- see drivers/tty/tty_port:tty_port_block_til_ready(). */ static int fwtty_port_carrier_raised(struct tty_port *tty_port) { struct fwtty_port *port = to_port(tty_port, port); int rc; rc = (port->mstatus & TIOCM_CAR); fwtty_dbg(port, "%d\n", rc); return rc; } static unsigned int set_termios(struct fwtty_port *port, struct tty_struct *tty) { unsigned int baud, frame; baud = tty_termios_baud_rate(&tty->termios); tty_termios_encode_baud_rate(&tty->termios, baud, baud); /* compute bit count of 2 frames */ frame = 12 + ((C_CSTOPB(tty)) ? 4 : 2) + ((C_PARENB(tty)) ? 2 : 0); switch (C_CSIZE(tty)) { case CS5: frame -= (C_CSTOPB(tty)) ? 1 : 0; break; case CS6: frame += 2; break; case CS7: frame += 4; break; case CS8: frame += 6; break; } port->cps = (baud << 1) / frame; port->status_mask = UART_LSR_OE; if (_I_FLAG(tty, BRKINT | PARMRK)) port->status_mask |= UART_LSR_BI; port->ignore_mask = 0; if (I_IGNBRK(tty)) { port->ignore_mask |= UART_LSR_BI; if (I_IGNPAR(tty)) port->ignore_mask |= UART_LSR_OE; } port->write_only = !C_CREAD(tty); /* turn off echo and newline xlat if loopback */ if (port->loopback) { tty->termios.c_lflag &= ~(ECHO | ECHOE | ECHOK | ECHOKE | ECHONL | ECHOPRT | ECHOCTL); tty->termios.c_oflag &= ~ONLCR; } return baud; } static int fwtty_port_activate(struct tty_port *tty_port, struct tty_struct *tty) { struct fwtty_port *port = to_port(tty_port, port); unsigned int baud; int err; set_bit(TTY_IO_ERROR, &tty->flags); err = dma_fifo_alloc(&port->tx_fifo, FWTTY_PORT_TXFIFO_LEN, cache_line_size(), port->max_payload, FWTTY_PORT_MAX_PEND_DMA, GFP_KERNEL); if (err) return err; spin_lock_bh(&port->lock); baud = set_termios(port, tty); /* if console, don't change carrier state */ if (!port->port.console) { port->mctrl = 0; if (baud != 0) port->mctrl = TIOCM_DTR | TIOCM_RTS; } if (C_CRTSCTS(tty) && ~port->mstatus & TIOCM_CTS) tty->hw_stopped = 1; __fwtty_write_port_status(port); spin_unlock_bh(&port->lock); clear_bit(TTY_IO_ERROR, &tty->flags); return 0; } /** * fwtty_port_shutdown * * Note: the tty port core ensures this is not the console and * manages TTY_IO_ERROR properly */ static void fwtty_port_shutdown(struct tty_port *tty_port) { struct fwtty_port *port = to_port(tty_port, port); /* TODO: cancel outstanding transactions */ cancel_delayed_work_sync(&port->emit_breaks); cancel_delayed_work_sync(&port->drain); spin_lock_bh(&port->lock); port->flags = 0; port->break_ctl = 0; port->overrun = 0; __fwtty_write_port_status(port); dma_fifo_free(&port->tx_fifo); spin_unlock_bh(&port->lock); } static int fwtty_open(struct tty_struct *tty, struct file *fp) { struct fwtty_port *port = tty->driver_data; return tty_port_open(&port->port, tty, fp); } static void fwtty_close(struct tty_struct *tty, struct file *fp) { struct fwtty_port *port = tty->driver_data; tty_port_close(&port->port, tty, fp); } static void fwtty_hangup(struct tty_struct *tty) { struct fwtty_port *port = tty->driver_data; tty_port_hangup(&port->port); } static void fwtty_cleanup(struct tty_struct *tty) { struct fwtty_port *port = tty->driver_data; tty->driver_data = NULL; fwtty_port_put(port); } static int fwtty_install(struct tty_driver *driver, struct tty_struct *tty) { struct fwtty_port *port = fwtty_port_get(tty->index); int err; err = tty_standard_install(driver, tty); if (!err) tty->driver_data = port; else fwtty_port_put(port); return err; } static int fwloop_install(struct tty_driver *driver, struct tty_struct *tty) { struct fwtty_port *port = fwtty_port_get(table_idx(tty->index)); int err; err = tty_standard_install(driver, tty); if (!err) tty->driver_data = port; else fwtty_port_put(port); return err; } static int fwtty_write(struct tty_struct *tty, const unsigned char *buf, int c) { struct fwtty_port *port = tty->driver_data; int n, len; fwtty_dbg(port, "%d\n", c); fwtty_profile_data(port->stats.writes, c); spin_lock_bh(&port->lock); n = dma_fifo_in(&port->tx_fifo, buf, c); len = dma_fifo_out_level(&port->tx_fifo); if (len < DRAIN_THRESHOLD) schedule_delayed_work(&port->drain, 1); spin_unlock_bh(&port->lock); if (len >= DRAIN_THRESHOLD) fwtty_tx(port, false); debug_short_write(port, c, n); return (n < 0) ? 0 : n; } static int fwtty_write_room(struct tty_struct *tty) { struct fwtty_port *port = tty->driver_data; int n; spin_lock_bh(&port->lock); n = dma_fifo_avail(&port->tx_fifo); spin_unlock_bh(&port->lock); fwtty_dbg(port, "%d\n", n); return n; } static int fwtty_chars_in_buffer(struct tty_struct *tty) { struct fwtty_port *port = tty->driver_data; int n; spin_lock_bh(&port->lock); n = dma_fifo_level(&port->tx_fifo); spin_unlock_bh(&port->lock); fwtty_dbg(port, "%d\n", n); return n; } static void fwtty_send_xchar(struct tty_struct *tty, char ch) { struct fwtty_port *port = tty->driver_data; fwtty_dbg(port, "%02x\n", ch); fwtty_write_xchar(port, ch); } static void fwtty_throttle(struct tty_struct *tty) { struct fwtty_port *port = tty->driver_data; /* * Ignore throttling (but not unthrottling). * It only makes sense to throttle when data will no longer be * accepted by the tty flip buffer. For example, it is * possible for received data to overflow the tty buffer long * before the line discipline ever has a chance to throttle the driver. * Additionally, the driver may have already completed the I/O * but the tty buffer is still emptying, so the line discipline is * throttling and unthrottling nothing. */ ++port->stats.throttled; } static void fwtty_unthrottle(struct tty_struct *tty) { struct fwtty_port *port = tty->driver_data; fwtty_dbg(port, "CRTSCTS: %d\n", C_CRTSCTS(tty) != 0); fwtty_profile_fifo(port, port->stats.unthrottle); spin_lock_bh(&port->lock); port->mctrl &= ~OOB_RX_THROTTLE; if (C_CRTSCTS(tty)) port->mctrl |= TIOCM_RTS; __fwtty_write_port_status(port); spin_unlock_bh(&port->lock); } static int check_msr_delta(struct fwtty_port *port, unsigned long mask, struct async_icount *prev) { struct async_icount now; int delta; now = port->icount; delta = ((mask & TIOCM_RNG && prev->rng != now.rng) || (mask & TIOCM_DSR && prev->dsr != now.dsr) || (mask & TIOCM_CAR && prev->dcd != now.dcd) || (mask & TIOCM_CTS && prev->cts != now.cts)); *prev = now; return delta; } static int wait_msr_change(struct fwtty_port *port, unsigned long mask) { struct async_icount prev; prev = port->icount; return wait_event_interruptible(port->port.delta_msr_wait, check_msr_delta(port, mask, &prev)); } static int get_serial_info(struct tty_struct *tty, struct serial_struct *ss) { struct fwtty_port *port = tty->driver_data; mutex_lock(&port->port.mutex); ss->type = PORT_UNKNOWN; ss->line = port->port.tty->index; ss->flags = port->port.flags; ss->xmit_fifo_size = FWTTY_PORT_TXFIFO_LEN; ss->baud_base = 400000000; ss->close_delay = port->port.close_delay; mutex_unlock(&port->port.mutex); return 0; } static int set_serial_info(struct tty_struct *tty, struct serial_struct *ss) { struct fwtty_port *port = tty->driver_data; if (ss->irq != 0 || ss->port != 0 || ss->custom_divisor != 0 || ss->baud_base != 400000000) return -EPERM; mutex_lock(&port->port.mutex); if (!capable(CAP_SYS_ADMIN)) { if (((ss->flags & ~ASYNC_USR_MASK) != (port->port.flags & ~ASYNC_USR_MASK))) { mutex_unlock(&port->port.mutex); return -EPERM; } } port->port.close_delay = ss->close_delay * HZ / 100; mutex_unlock(&port->port.mutex); return 0; } static int fwtty_ioctl(struct tty_struct *tty, unsigned int cmd, unsigned long arg) { struct fwtty_port *port = tty->driver_data; int err; switch (cmd) { case TIOCMIWAIT: err = wait_msr_change(port, arg); break; default: err = -ENOIOCTLCMD; } return err; } static void fwtty_set_termios(struct tty_struct *tty, struct ktermios *old) { struct fwtty_port *port = tty->driver_data; unsigned int baud; spin_lock_bh(&port->lock); baud = set_termios(port, tty); if ((baud == 0) && (old->c_cflag & CBAUD)) { port->mctrl &= ~(TIOCM_DTR | TIOCM_RTS); } else if ((baud != 0) && !(old->c_cflag & CBAUD)) { if (C_CRTSCTS(tty) || !tty_throttled(tty)) port->mctrl |= TIOCM_DTR | TIOCM_RTS; else port->mctrl |= TIOCM_DTR; } __fwtty_write_port_status(port); spin_unlock_bh(&port->lock); if (old->c_cflag & CRTSCTS) { if (!C_CRTSCTS(tty)) { tty->hw_stopped = 0; fwtty_restart_tx(port); } } else if (C_CRTSCTS(tty) && ~port->mstatus & TIOCM_CTS) { tty->hw_stopped = 1; } } /** * fwtty_break_ctl - start/stop sending breaks * * Signals the remote to start or stop generating simulated breaks. * First, stop dequeueing from the fifo and wait for writer/drain to leave tx * before signalling the break line status. This guarantees any pending rx will * be queued to the line discipline before break is simulated on the remote. * Conversely, turning off break_ctl requires signalling the line status change, * then enabling tx. */ static int fwtty_break_ctl(struct tty_struct *tty, int state) { struct fwtty_port *port = tty->driver_data; long ret; fwtty_dbg(port, "%d\n", state); if (state == -1) { set_bit(STOP_TX, &port->flags); ret = wait_event_interruptible_timeout(port->wait_tx, !test_bit(IN_TX, &port->flags), 10); if (ret == 0 || ret == -ERESTARTSYS) { clear_bit(STOP_TX, &port->flags); fwtty_restart_tx(port); return -EINTR; } } spin_lock_bh(&port->lock); port->break_ctl = (state == -1); __fwtty_write_port_status(port); spin_unlock_bh(&port->lock); if (state == 0) { spin_lock_bh(&port->lock); dma_fifo_reset(&port->tx_fifo); clear_bit(STOP_TX, &port->flags); spin_unlock_bh(&port->lock); } return 0; } static int fwtty_tiocmget(struct tty_struct *tty) { struct fwtty_port *port = tty->driver_data; unsigned int tiocm; spin_lock_bh(&port->lock); tiocm = (port->mctrl & MCTRL_MASK) | (port->mstatus & ~MCTRL_MASK); spin_unlock_bh(&port->lock); fwtty_dbg(port, "%x\n", tiocm); return tiocm; } static int fwtty_tiocmset(struct tty_struct *tty, unsigned int set, unsigned int clear) { struct fwtty_port *port = tty->driver_data; fwtty_dbg(port, "set: %x clear: %x\n", set, clear); /* TODO: simulate loopback if TIOCM_LOOP set */ spin_lock_bh(&port->lock); port->mctrl &= ~(clear & MCTRL_MASK & 0xffff); port->mctrl |= set & MCTRL_MASK & 0xffff; __fwtty_write_port_status(port); spin_unlock_bh(&port->lock); return 0; } static int fwtty_get_icount(struct tty_struct *tty, struct serial_icounter_struct *icount) { struct fwtty_port *port = tty->driver_data; struct stats stats; memcpy(&stats, &port->stats, sizeof(stats)); if (port->port.console) (*port->fwcon_ops->stats)(&stats, port->con_data); icount->cts = port->icount.cts; icount->dsr = port->icount.dsr; icount->rng = port->icount.rng; icount->dcd = port->icount.dcd; icount->rx = port->icount.rx; icount->tx = port->icount.tx + stats.xchars; icount->frame = port->icount.frame; icount->overrun = port->icount.overrun; icount->parity = port->icount.parity; icount->brk = port->icount.brk; icount->buf_overrun = port->icount.overrun; return 0; } static void fwtty_proc_show_port(struct seq_file *m, struct fwtty_port *port) { struct stats stats; memcpy(&stats, &port->stats, sizeof(stats)); if (port->port.console) (*port->fwcon_ops->stats)(&stats, port->con_data); seq_printf(m, " addr:%012llx tx:%d rx:%d", port->rx_handler.offset, port->icount.tx + stats.xchars, port->icount.rx); seq_printf(m, " cts:%d dsr:%d rng:%d dcd:%d", port->icount.cts, port->icount.dsr, port->icount.rng, port->icount.dcd); seq_printf(m, " fe:%d oe:%d pe:%d brk:%d", port->icount.frame, port->icount.overrun, port->icount.parity, port->icount.brk); } static void fwtty_debugfs_show_port(struct seq_file *m, struct fwtty_port *port) { struct stats stats; memcpy(&stats, &port->stats, sizeof(stats)); if (port->port.console) (*port->fwcon_ops->stats)(&stats, port->con_data); seq_printf(m, " dr:%d st:%d err:%d lost:%d", stats.dropped, stats.tx_stall, stats.fifo_errs, stats.lost); seq_printf(m, " pkts:%d thr:%d", stats.sent, stats.throttled); if (port->port.console) { seq_puts(m, "\n "); (*port->fwcon_ops->proc_show)(m, port->con_data); } fwtty_dump_profile(m, &port->stats); } static void fwtty_debugfs_show_peer(struct seq_file *m, struct fwtty_peer *peer) { int generation = peer->generation; smp_rmb(); seq_printf(m, " %s:", dev_name(&peer->unit->device)); seq_printf(m, " node:%04x gen:%d", peer->node_id, generation); seq_printf(m, " sp:%d max:%d guid:%016llx", peer->speed, peer->max_payload, (unsigned long long)peer->guid); seq_printf(m, " mgmt:%012llx", (unsigned long long)peer->mgmt_addr); seq_printf(m, " addr:%012llx", (unsigned long long)peer->status_addr); seq_putc(m, '\n'); } static int fwtty_proc_show(struct seq_file *m, void *v) { struct fwtty_port *port; int i; seq_puts(m, "fwserinfo: 1.0 driver: 1.0\n"); for (i = 0; i < MAX_TOTAL_PORTS && (port = fwtty_port_get(i)); ++i) { seq_printf(m, "%2d:", i); if (capable(CAP_SYS_ADMIN)) fwtty_proc_show_port(m, port); fwtty_port_put(port); seq_puts(m, "\n"); } return 0; } static int fwtty_stats_show(struct seq_file *m, void *v) { struct fw_serial *serial = m->private; struct fwtty_port *port; int i; for (i = 0; i < num_ports; ++i) { port = fwtty_port_get(serial->ports[i]->index); if (port) { seq_printf(m, "%2d:", port->index); fwtty_proc_show_port(m, port); fwtty_debugfs_show_port(m, port); fwtty_port_put(port); seq_puts(m, "\n"); } } return 0; } DEFINE_SHOW_ATTRIBUTE(fwtty_stats); static int fwtty_peers_show(struct seq_file *m, void *v) { struct fw_serial *serial = m->private; struct fwtty_peer *peer; rcu_read_lock(); seq_printf(m, "card: %s guid: %016llx\n", dev_name(serial->card->device), (unsigned long long)serial->card->guid); list_for_each_entry_rcu(peer, &serial->peer_list, list) fwtty_debugfs_show_peer(m, peer); rcu_read_unlock(); return 0; } DEFINE_SHOW_ATTRIBUTE(fwtty_peers); static const struct tty_port_operations fwtty_port_ops = { .dtr_rts = fwtty_port_dtr_rts, .carrier_raised = fwtty_port_carrier_raised, .shutdown = fwtty_port_shutdown, .activate = fwtty_port_activate, }; static const struct tty_operations fwtty_ops = { .open = fwtty_open, .close = fwtty_close, .hangup = fwtty_hangup, .cleanup = fwtty_cleanup, .install = fwtty_install, .write = fwtty_write, .write_room = fwtty_write_room, .chars_in_buffer = fwtty_chars_in_buffer, .send_xchar = fwtty_send_xchar, .throttle = fwtty_throttle, .unthrottle = fwtty_unthrottle, .ioctl = fwtty_ioctl, .set_termios = fwtty_set_termios, .break_ctl = fwtty_break_ctl, .tiocmget = fwtty_tiocmget, .tiocmset = fwtty_tiocmset, .get_icount = fwtty_get_icount, .set_serial = set_serial_info, .get_serial = get_serial_info, .proc_show = fwtty_proc_show, }; static const struct tty_operations fwloop_ops = { .open = fwtty_open, .close = fwtty_close, .hangup = fwtty_hangup, .cleanup = fwtty_cleanup, .install = fwloop_install, .write = fwtty_write, .write_room = fwtty_write_room, .chars_in_buffer = fwtty_chars_in_buffer, .send_xchar = fwtty_send_xchar, .throttle = fwtty_throttle, .unthrottle = fwtty_unthrottle, .ioctl = fwtty_ioctl, .set_termios = fwtty_set_termios, .break_ctl = fwtty_break_ctl, .tiocmget = fwtty_tiocmget, .tiocmset = fwtty_tiocmset, .get_icount = fwtty_get_icount, .set_serial = set_serial_info, .get_serial = get_serial_info, }; static inline int mgmt_pkt_expected_len(__be16 code) { static const struct fwserial_mgmt_pkt pkt; switch (be16_to_cpu(code)) { case FWSC_VIRT_CABLE_PLUG: return sizeof(pkt.hdr) + sizeof(pkt.plug_req); case FWSC_VIRT_CABLE_PLUG_RSP: /* | FWSC_RSP_OK */ return sizeof(pkt.hdr) + sizeof(pkt.plug_rsp); case FWSC_VIRT_CABLE_UNPLUG: case FWSC_VIRT_CABLE_UNPLUG_RSP: case FWSC_VIRT_CABLE_PLUG_RSP | FWSC_RSP_NACK: case FWSC_VIRT_CABLE_UNPLUG_RSP | FWSC_RSP_NACK: return sizeof(pkt.hdr); default: return -1; } } static inline void fill_plug_params(struct virt_plug_params *params, struct fwtty_port *port) { u64 status_addr = port->rx_handler.offset; u64 fifo_addr = port->rx_handler.offset + 4; size_t fifo_len = port->rx_handler.length - 4; params->status_hi = cpu_to_be32(status_addr >> 32); params->status_lo = cpu_to_be32(status_addr); params->fifo_hi = cpu_to_be32(fifo_addr >> 32); params->fifo_lo = cpu_to_be32(fifo_addr); params->fifo_len = cpu_to_be32(fifo_len); } static inline void fill_plug_req(struct fwserial_mgmt_pkt *pkt, struct fwtty_port *port) { pkt->hdr.code = cpu_to_be16(FWSC_VIRT_CABLE_PLUG); pkt->hdr.len = cpu_to_be16(mgmt_pkt_expected_len(pkt->hdr.code)); fill_plug_params(&pkt->plug_req, port); } static inline void fill_plug_rsp_ok(struct fwserial_mgmt_pkt *pkt, struct fwtty_port *port) { pkt->hdr.code = cpu_to_be16(FWSC_VIRT_CABLE_PLUG_RSP); pkt->hdr.len = cpu_to_be16(mgmt_pkt_expected_len(pkt->hdr.code)); fill_plug_params(&pkt->plug_rsp, port); } static inline void fill_plug_rsp_nack(struct fwserial_mgmt_pkt *pkt) { pkt->hdr.code = cpu_to_be16(FWSC_VIRT_CABLE_PLUG_RSP | FWSC_RSP_NACK); pkt->hdr.len = cpu_to_be16(mgmt_pkt_expected_len(pkt->hdr.code)); } static inline void fill_unplug_rsp_nack(struct fwserial_mgmt_pkt *pkt) { pkt->hdr.code = cpu_to_be16(FWSC_VIRT_CABLE_UNPLUG_RSP | FWSC_RSP_NACK); pkt->hdr.len = cpu_to_be16(mgmt_pkt_expected_len(pkt->hdr.code)); } static inline void fill_unplug_rsp_ok(struct fwserial_mgmt_pkt *pkt) { pkt->hdr.code = cpu_to_be16(FWSC_VIRT_CABLE_UNPLUG_RSP); pkt->hdr.len = cpu_to_be16(mgmt_pkt_expected_len(pkt->hdr.code)); } static void fwserial_virt_plug_complete(struct fwtty_peer *peer, struct virt_plug_params *params) { struct fwtty_port *port = peer->port; peer->status_addr = be32_to_u64(params->status_hi, params->status_lo); peer->fifo_addr = be32_to_u64(params->fifo_hi, params->fifo_lo); peer->fifo_len = be32_to_cpu(params->fifo_len); peer_set_state(peer, FWPS_ATTACHED); /* reconfigure tx_fifo optimally for this peer */ spin_lock_bh(&port->lock); port->max_payload = min(peer->max_payload, peer->fifo_len); dma_fifo_change_tx_limit(&port->tx_fifo, port->max_payload); spin_unlock_bh(&peer->port->lock); if (port->port.console && port->fwcon_ops->notify) (*port->fwcon_ops->notify)(FWCON_NOTIFY_ATTACH, port->con_data); fwtty_info(&peer->unit, "peer (guid:%016llx) connected on %s\n", (unsigned long long)peer->guid, dev_name(port->device)); } static inline int fwserial_send_mgmt_sync(struct fwtty_peer *peer, struct fwserial_mgmt_pkt *pkt) { int generation; int rcode, tries = 5; do { generation = peer->generation; smp_rmb(); rcode = fw_run_transaction(peer->serial->card, TCODE_WRITE_BLOCK_REQUEST, peer->node_id, generation, peer->speed, peer->mgmt_addr, pkt, be16_to_cpu(pkt->hdr.len)); if (rcode == RCODE_BUSY || rcode == RCODE_SEND_ERROR || rcode == RCODE_GENERATION) { fwtty_dbg(&peer->unit, "mgmt write error: %d\n", rcode); continue; } else { break; } } while (--tries > 0); return rcode; } /** * fwserial_claim_port - attempt to claim port @ index for peer * * Returns ptr to claimed port or error code (as ERR_PTR()) * Can sleep - must be called from process context */ static struct fwtty_port *fwserial_claim_port(struct fwtty_peer *peer, int index) { struct fwtty_port *port; if (index < 0 || index >= num_ports) return ERR_PTR(-EINVAL); /* must guarantee that previous port releases have completed */ synchronize_rcu(); port = peer->serial->ports[index]; spin_lock_bh(&port->lock); if (!rcu_access_pointer(port->peer)) rcu_assign_pointer(port->peer, peer); else port = ERR_PTR(-EBUSY); spin_unlock_bh(&port->lock); return port; } /** * fwserial_find_port - find avail port and claim for peer * * Returns ptr to claimed port or NULL if none avail * Can sleep - must be called from process context */ static struct fwtty_port *fwserial_find_port(struct fwtty_peer *peer) { struct fwtty_port **ports = peer->serial->ports; int i; /* must guarantee that previous port releases have completed */ synchronize_rcu(); /* TODO: implement optional GUID-to-specific port # matching */ /* find an unattached port (but not the loopback port, if present) */ for (i = 0; i < num_ttys; ++i) { spin_lock_bh(&ports[i]->lock); if (!ports[i]->peer) { /* claim port */ rcu_assign_pointer(ports[i]->peer, peer); spin_unlock_bh(&ports[i]->lock); return ports[i]; } spin_unlock_bh(&ports[i]->lock); } return NULL; } static void fwserial_release_port(struct fwtty_port *port, bool reset) { /* drop carrier (and all other line status) */ if (reset) fwtty_update_port_status(port, 0); spin_lock_bh(&port->lock); /* reset dma fifo max transmission size back to S100 */ port->max_payload = link_speed_to_max_payload(SCODE_100); dma_fifo_change_tx_limit(&port->tx_fifo, port->max_payload); RCU_INIT_POINTER(port->peer, NULL); spin_unlock_bh(&port->lock); if (port->port.console && port->fwcon_ops->notify) (*port->fwcon_ops->notify)(FWCON_NOTIFY_DETACH, port->con_data); } static void fwserial_plug_timeout(struct timer_list *t) { struct fwtty_peer *peer = from_timer(peer, t, timer); struct fwtty_port *port; spin_lock_bh(&peer->lock); if (peer->state != FWPS_PLUG_PENDING) { spin_unlock_bh(&peer->lock); return; } port = peer_revert_state(peer); spin_unlock_bh(&peer->lock); if (port) fwserial_release_port(port, false); } /** * fwserial_connect_peer - initiate virtual cable with peer * * Returns 0 if VIRT_CABLE_PLUG request was successfully sent, * otherwise error code. Must be called from process context. */ static int fwserial_connect_peer(struct fwtty_peer *peer) { struct fwtty_port *port; struct fwserial_mgmt_pkt *pkt; int err, rcode; pkt = kmalloc(sizeof(*pkt), GFP_KERNEL); if (!pkt) return -ENOMEM; port = fwserial_find_port(peer); if (!port) { fwtty_err(&peer->unit, "avail ports in use\n"); err = -EBUSY; goto free_pkt; } spin_lock_bh(&peer->lock); /* only initiate VIRT_CABLE_PLUG if peer is currently not attached */ if (peer->state != FWPS_NOT_ATTACHED) { err = -EBUSY; goto release_port; } peer->port = port; peer_set_state(peer, FWPS_PLUG_PENDING); fill_plug_req(pkt, peer->port); mod_timer(&peer->timer, jiffies + VIRT_CABLE_PLUG_TIMEOUT); spin_unlock_bh(&peer->lock); rcode = fwserial_send_mgmt_sync(peer, pkt); spin_lock_bh(&peer->lock); if (peer->state == FWPS_PLUG_PENDING && rcode != RCODE_COMPLETE) { if (rcode == RCODE_CONFLICT_ERROR) err = -EAGAIN; else err = -EIO; goto cancel_timer; } spin_unlock_bh(&peer->lock); kfree(pkt); return 0; cancel_timer: del_timer(&peer->timer); peer_revert_state(peer); release_port: spin_unlock_bh(&peer->lock); fwserial_release_port(port, false); free_pkt: kfree(pkt); return err; } /** * fwserial_close_port - * HUP the tty (if the tty exists) and unregister the tty device. * Only used by the unit driver upon unit removal to disconnect and * cleanup all attached ports * * The port reference is put by fwtty_cleanup (if a reference was * ever taken). */ static void fwserial_close_port(struct tty_driver *driver, struct fwtty_port *port) { struct tty_struct *tty; mutex_lock(&port->port.mutex); tty = tty_port_tty_get(&port->port); if (tty) { tty_vhangup(tty); tty_kref_put(tty); } mutex_unlock(&port->port.mutex); if (driver == fwloop_driver) tty_unregister_device(driver, loop_idx(port)); else tty_unregister_device(driver, port->index); } /** * fwserial_lookup - finds first fw_serial associated with card * @card: fw_card to match * * NB: caller must be holding fwserial_list_mutex */ static struct fw_serial *fwserial_lookup(struct fw_card *card) { struct fw_serial *serial; list_for_each_entry(serial, &fwserial_list, list) { if (card == serial->card) return serial; } return NULL; } /** * __fwserial_lookup_rcu - finds first fw_serial associated with card * @card: fw_card to match * * NB: caller must be inside rcu_read_lock() section */ static struct fw_serial *__fwserial_lookup_rcu(struct fw_card *card) { struct fw_serial *serial; list_for_each_entry_rcu(serial, &fwserial_list, list) { if (card == serial->card) return serial; } return NULL; } /** * __fwserial_peer_by_node_id - finds a peer matching the given generation + id * * If a matching peer could not be found for the specified generation/node id, * this could be because: * a) the generation has changed and one of the nodes hasn't updated yet * b) the remote node has created its remote unit device before this * local node has created its corresponding remote unit device * In either case, the remote node should retry * * Note: caller must be in rcu_read_lock() section */ static struct fwtty_peer *__fwserial_peer_by_node_id(struct fw_card *card, int generation, int id) { struct fw_serial *serial; struct fwtty_peer *peer; serial = __fwserial_lookup_rcu(card); if (!serial) { /* * Something is very wrong - there should be a matching * fw_serial structure for every fw_card. Maybe the remote node * has created its remote unit device before this driver has * been probed for any unit devices... */ fwtty_err(card, "unknown card (guid %016llx)\n", (unsigned long long)card->guid); return NULL; } list_for_each_entry_rcu(peer, &serial->peer_list, list) { int g = peer->generation; smp_rmb(); if (generation == g && id == peer->node_id) return peer; } return NULL; } #ifdef DEBUG static void __dump_peer_list(struct fw_card *card) { struct fw_serial *serial; struct fwtty_peer *peer; serial = __fwserial_lookup_rcu(card); if (!serial) return; list_for_each_entry_rcu(peer, &serial->peer_list, list) { int g = peer->generation; smp_rmb(); fwtty_dbg(card, "peer(%d:%x) guid: %016llx\n", g, peer->node_id, (unsigned long long)peer->guid); } } #else #define __dump_peer_list(s) #endif static void fwserial_auto_connect(struct work_struct *work) { struct fwtty_peer *peer = to_peer(to_delayed_work(work), connect); int err; err = fwserial_connect_peer(peer); if (err == -EAGAIN && ++peer->connect_retries < MAX_CONNECT_RETRIES) schedule_delayed_work(&peer->connect, CONNECT_RETRY_DELAY); } static void fwserial_peer_workfn(struct work_struct *work) { struct fwtty_peer *peer = to_peer(work, work); peer->workfn(work); } /** * fwserial_add_peer - add a newly probed 'serial' unit device as a 'peer' * @serial: aggregate representing the specific fw_card to add the peer to * @unit: 'peer' to create and add to peer_list of serial * * Adds a 'peer' (ie, a local or remote 'serial' unit device) to the list of * peers for a specific fw_card. Optionally, auto-attach this peer to an * available tty port. This function is called either directly or indirectly * as a result of a 'serial' unit device being created & probed. * * Note: this function is serialized with fwserial_remove_peer() by the * fwserial_list_mutex held in fwserial_probe(). * * A 1:1 correspondence between an fw_unit and an fwtty_peer is maintained * via the dev_set_drvdata() for the device of the fw_unit. */ static int fwserial_add_peer(struct fw_serial *serial, struct fw_unit *unit) { struct device *dev = &unit->device; struct fw_device *parent = fw_parent_device(unit); struct fwtty_peer *peer; struct fw_csr_iterator ci; int key, val; int generation; peer = kzalloc(sizeof(*peer), GFP_KERNEL); if (!peer) return -ENOMEM; peer_set_state(peer, FWPS_NOT_ATTACHED); dev_set_drvdata(dev, peer); peer->unit = unit; peer->guid = (u64)parent->config_rom[3] << 32 | parent->config_rom[4]; peer->speed = parent->max_speed; peer->max_payload = min(device_max_receive(parent), link_speed_to_max_payload(peer->speed)); generation = parent->generation; smp_rmb(); peer->node_id = parent->node_id; smp_wmb(); peer->generation = generation; /* retrieve the mgmt bus addr from the unit directory */ fw_csr_iterator_init(&ci, unit->directory); while (fw_csr_iterator_next(&ci, &key, &val)) { if (key == (CSR_OFFSET | CSR_DEPENDENT_INFO)) { peer->mgmt_addr = CSR_REGISTER_BASE + 4 * val; break; } } if (peer->mgmt_addr == 0ULL) { /* * No mgmt address effectively disables VIRT_CABLE_PLUG - * this peer will not be able to attach to a remote */ peer_set_state(peer, FWPS_NO_MGMT_ADDR); } spin_lock_init(&peer->lock); peer->port = NULL; timer_setup(&peer->timer, fwserial_plug_timeout, 0); INIT_WORK(&peer->work, fwserial_peer_workfn); INIT_DELAYED_WORK(&peer->connect, fwserial_auto_connect); /* associate peer with specific fw_card */ peer->serial = serial; list_add_rcu(&peer->list, &serial->peer_list); fwtty_info(&peer->unit, "peer added (guid:%016llx)\n", (unsigned long long)peer->guid); /* identify the local unit & virt cable to loopback port */ if (parent->is_local) { serial->self = peer; if (create_loop_dev) { struct fwtty_port *port; port = fwserial_claim_port(peer, num_ttys); if (!IS_ERR(port)) { struct virt_plug_params params; spin_lock_bh(&peer->lock); peer->port = port; fill_plug_params(¶ms, port); fwserial_virt_plug_complete(peer, ¶ms); spin_unlock_bh(&peer->lock); fwtty_write_port_status(port); } } } else if (auto_connect) { /* auto-attach to remote units only (if policy allows) */ schedule_delayed_work(&peer->connect, 1); } return 0; } /** * fwserial_remove_peer - remove a 'serial' unit device as a 'peer' * * Remove a 'peer' from its list of peers. This function is only * called by fwserial_remove() on bus removal of the unit device. * * Note: this function is serialized with fwserial_add_peer() by the * fwserial_list_mutex held in fwserial_remove(). */ static void fwserial_remove_peer(struct fwtty_peer *peer) { struct fwtty_port *port; spin_lock_bh(&peer->lock); peer_set_state(peer, FWPS_GONE); spin_unlock_bh(&peer->lock); cancel_delayed_work_sync(&peer->connect); cancel_work_sync(&peer->work); spin_lock_bh(&peer->lock); /* if this unit is the local unit, clear link */ if (peer == peer->serial->self) peer->serial->self = NULL; /* cancel the request timeout timer (if running) */ del_timer(&peer->timer); port = peer->port; peer->port = NULL; list_del_rcu(&peer->list); fwtty_info(&peer->unit, "peer removed (guid:%016llx)\n", (unsigned long long)peer->guid); spin_unlock_bh(&peer->lock); if (port) fwserial_release_port(port, true); synchronize_rcu(); kfree(peer); } /** * fwserial_create - init everything to create TTYs for a specific fw_card * @unit: fw_unit for first 'serial' unit device probed for this fw_card * * This function inits the aggregate structure (an fw_serial instance) * used to manage the TTY ports registered by a specific fw_card. Also, the * unit device is added as the first 'peer'. * * This unit device may represent a local unit device (as specified by the * config ROM unit directory) or it may represent a remote unit device * (as specified by the reading of the remote node's config ROM). * * Returns 0 to indicate "ownership" of the unit device, or a negative errno * value to indicate which error. */ static int fwserial_create(struct fw_unit *unit) { struct fw_device *parent = fw_parent_device(unit); struct fw_card *card = parent->card; struct fw_serial *serial; struct fwtty_port *port; struct device *tty_dev; int i, j; int err; serial = kzalloc(sizeof(*serial), GFP_KERNEL); if (!serial) return -ENOMEM; kref_init(&serial->kref); serial->card = card; INIT_LIST_HEAD(&serial->peer_list); for (i = 0; i < num_ports; ++i) { port = kzalloc(sizeof(*port), GFP_KERNEL); if (!port) { err = -ENOMEM; goto free_ports; } tty_port_init(&port->port); port->index = FWTTY_INVALID_INDEX; port->port.ops = &fwtty_port_ops; port->serial = serial; tty_buffer_set_limit(&port->port, 128 * 1024); spin_lock_init(&port->lock); INIT_DELAYED_WORK(&port->drain, fwtty_drain_tx); INIT_DELAYED_WORK(&port->emit_breaks, fwtty_emit_breaks); INIT_WORK(&port->hangup, fwtty_do_hangup); init_waitqueue_head(&port->wait_tx); port->max_payload = link_speed_to_max_payload(SCODE_100); dma_fifo_init(&port->tx_fifo); RCU_INIT_POINTER(port->peer, NULL); serial->ports[i] = port; /* get unique bus addr region for port's status & recv fifo */ port->rx_handler.length = FWTTY_PORT_RXFIFO_LEN + 4; port->rx_handler.address_callback = fwtty_port_handler; port->rx_handler.callback_data = port; /* * XXX: use custom memory region above cpu physical memory addrs * this will ease porting to 64-bit firewire adapters */ err = fw_core_add_address_handler(&port->rx_handler, &fw_high_memory_region); if (err) { kfree(port); goto free_ports; } } /* preserve i for error cleanup */ err = fwtty_ports_add(serial); if (err) { fwtty_err(&unit, "no space in port table\n"); goto free_ports; } for (j = 0; j < num_ttys; ++j) { tty_dev = tty_port_register_device(&serial->ports[j]->port, fwtty_driver, serial->ports[j]->index, card->device); if (IS_ERR(tty_dev)) { err = PTR_ERR(tty_dev); fwtty_err(&unit, "register tty device error (%d)\n", err); goto unregister_ttys; } serial->ports[j]->device = tty_dev; } /* preserve j for error cleanup */ if (create_loop_dev) { struct device *loop_dev; loop_dev = tty_port_register_device(&serial->ports[j]->port, fwloop_driver, loop_idx(serial->ports[j]), card->device); if (IS_ERR(loop_dev)) { err = PTR_ERR(loop_dev); fwtty_err(&unit, "create loop device failed (%d)\n", err); goto unregister_ttys; } serial->ports[j]->device = loop_dev; serial->ports[j]->loopback = true; } if (!IS_ERR_OR_NULL(fwserial_debugfs)) { serial->debugfs = debugfs_create_dir(dev_name(&unit->device), fwserial_debugfs); if (!IS_ERR_OR_NULL(serial->debugfs)) { debugfs_create_file("peers", 0444, serial->debugfs, serial, &fwtty_peers_fops); debugfs_create_file("stats", 0444, serial->debugfs, serial, &fwtty_stats_fops); } } list_add_rcu(&serial->list, &fwserial_list); fwtty_notice(&unit, "TTY over FireWire on device %s (guid %016llx)\n", dev_name(card->device), (unsigned long long)card->guid); err = fwserial_add_peer(serial, unit); if (!err) return 0; fwtty_err(&unit, "unable to add peer unit device (%d)\n", err); /* fall-through to error processing */ debugfs_remove_recursive(serial->debugfs); list_del_rcu(&serial->list); if (create_loop_dev) tty_unregister_device(fwloop_driver, loop_idx(serial->ports[j])); unregister_ttys: for (--j; j >= 0; --j) tty_unregister_device(fwtty_driver, serial->ports[j]->index); kref_put(&serial->kref, fwserial_destroy); return err; free_ports: for (--i; i >= 0; --i) { tty_port_destroy(&serial->ports[i]->port); kfree(serial->ports[i]); } kfree(serial); return err; } /** * fwserial_probe: bus probe function for firewire 'serial' unit devices * * A 'serial' unit device is created and probed as a result of: * - declaring a ieee1394 bus id table for 'devices' matching a fabricated * 'serial' unit specifier id * - adding a unit directory to the config ROM(s) for a 'serial' unit * * The firewire core registers unit devices by enumerating unit directories * of a node's config ROM after reading the config ROM when a new node is * added to the bus topology after a bus reset. * * The practical implications of this are: * - this probe is called for both local and remote nodes that have a 'serial' * unit directory in their config ROM (that matches the specifiers in * fwserial_id_table). * - no specific order is enforced for local vs. remote unit devices * * This unit driver copes with the lack of specific order in the same way the * firewire net driver does -- each probe, for either a local or remote unit * device, is treated as a 'peer' (has a struct fwtty_peer instance) and the * first peer created for a given fw_card (tracked by the global fwserial_list) * creates the underlying TTYs (aggregated in a fw_serial instance). * * NB: an early attempt to differentiate local & remote unit devices by creating * peers only for remote units and fw_serial instances (with their * associated TTY devices) only for local units was discarded. Managing * the peer lifetimes on device removal proved too complicated. * * fwserial_probe/fwserial_remove are effectively serialized by the * fwserial_list_mutex. This is necessary because the addition of the first peer * for a given fw_card will trigger the creation of the fw_serial for that * fw_card, which must not simultaneously contend with the removal of the * last peer for a given fw_card triggering the destruction of the same * fw_serial for the same fw_card. */ static int fwserial_probe(struct fw_unit *unit, const struct ieee1394_device_id *id) { struct fw_serial *serial; int err; mutex_lock(&fwserial_list_mutex); serial = fwserial_lookup(fw_parent_device(unit)->card); if (!serial) err = fwserial_create(unit); else err = fwserial_add_peer(serial, unit); mutex_unlock(&fwserial_list_mutex); return err; } /** * fwserial_remove: bus removal function for firewire 'serial' unit devices * * The corresponding 'peer' for this unit device is removed from the list of * peers for the associated fw_serial (which has a 1:1 correspondence with a * specific fw_card). If this is the last peer being removed, then trigger * the destruction of the underlying TTYs. */ static void fwserial_remove(struct fw_unit *unit) { struct fwtty_peer *peer = dev_get_drvdata(&unit->device); struct fw_serial *serial = peer->serial; int i; mutex_lock(&fwserial_list_mutex); fwserial_remove_peer(peer); if (list_empty(&serial->peer_list)) { /* unlink from the fwserial_list here */ list_del_rcu(&serial->list); debugfs_remove_recursive(serial->debugfs); for (i = 0; i < num_ttys; ++i) fwserial_close_port(fwtty_driver, serial->ports[i]); if (create_loop_dev) fwserial_close_port(fwloop_driver, serial->ports[i]); kref_put(&serial->kref, fwserial_destroy); } mutex_unlock(&fwserial_list_mutex); } /** * fwserial_update: bus update function for 'firewire' serial unit devices * * Updates the new node_id and bus generation for this peer. Note that locking * is unnecessary; but careful memory barrier usage is important to enforce the * load and store order of generation & node_id. * * The fw-core orders the write of node_id before generation in the parent * fw_device to ensure that a stale node_id cannot be used with a current * bus generation. So the generation value must be read before the node_id. * * In turn, this orders the write of node_id before generation in the peer to * also ensure a stale node_id cannot be used with a current bus generation. */ static void fwserial_update(struct fw_unit *unit) { struct fw_device *parent = fw_parent_device(unit); struct fwtty_peer *peer = dev_get_drvdata(&unit->device); int generation; generation = parent->generation; smp_rmb(); peer->node_id = parent->node_id; smp_wmb(); peer->generation = generation; } static const struct ieee1394_device_id fwserial_id_table[] = { { .match_flags = IEEE1394_MATCH_SPECIFIER_ID | IEEE1394_MATCH_VERSION, .specifier_id = LINUX_VENDOR_ID, .version = FWSERIAL_VERSION, }, { } }; static struct fw_driver fwserial_driver = { .driver = { .owner = THIS_MODULE, .name = KBUILD_MODNAME, .bus = &fw_bus_type, }, .probe = fwserial_probe, .update = fwserial_update, .remove = fwserial_remove, .id_table = fwserial_id_table, }; #define FW_UNIT_SPECIFIER(id) ((CSR_SPECIFIER_ID << 24) | (id)) #define FW_UNIT_VERSION(ver) ((CSR_VERSION << 24) | (ver)) #define FW_UNIT_ADDRESS(ofs) (((CSR_OFFSET | CSR_DEPENDENT_INFO) << 24) \ | (((ofs) - CSR_REGISTER_BASE) >> 2)) /* XXX: config ROM definitons could be improved with semi-automated offset * and length calculation */ #define FW_ROM_LEN(quads) ((quads) << 16) #define FW_ROM_DESCRIPTOR(ofs) (((CSR_LEAF | CSR_DESCRIPTOR) << 24) | (ofs)) struct fwserial_unit_directory_data { u32 len_crc; u32 unit_specifier; u32 unit_sw_version; u32 unit_addr_offset; u32 desc1_ofs; u32 desc1_len_crc; u32 desc1_data[5]; } __packed; static struct fwserial_unit_directory_data fwserial_unit_directory_data = { .len_crc = FW_ROM_LEN(4), .unit_specifier = FW_UNIT_SPECIFIER(LINUX_VENDOR_ID), .unit_sw_version = FW_UNIT_VERSION(FWSERIAL_VERSION), .desc1_ofs = FW_ROM_DESCRIPTOR(1), .desc1_len_crc = FW_ROM_LEN(5), .desc1_data = { 0x00000000, /* type = text */ 0x00000000, /* enc = ASCII, lang EN */ 0x4c696e75, /* 'Linux TTY' */ 0x78205454, 0x59000000, }, }; static struct fw_descriptor fwserial_unit_directory = { .length = sizeof(fwserial_unit_directory_data) / sizeof(u32), .key = (CSR_DIRECTORY | CSR_UNIT) << 24, .data = (u32 *)&fwserial_unit_directory_data, }; /* * The management address is in the unit space region but above other known * address users (to keep wild writes from causing havoc) */ static const struct fw_address_region fwserial_mgmt_addr_region = { .start = CSR_REGISTER_BASE + 0x1e0000ULL, .end = 0x1000000000000ULL, }; static struct fw_address_handler fwserial_mgmt_addr_handler; /** * fwserial_handle_plug_req - handle VIRT_CABLE_PLUG request work * @work: ptr to peer->work * * Attempts to complete the VIRT_CABLE_PLUG handshake sequence for this peer. * * This checks for a collided request-- ie, that a VIRT_CABLE_PLUG request was * already sent to this peer. If so, the collision is resolved by comparing * guid values; the loser sends the plug response. * * Note: if an error prevents a response, don't do anything -- the * remote will timeout its request. */ static void fwserial_handle_plug_req(struct work_struct *work) { struct fwtty_peer *peer = to_peer(work, work); struct virt_plug_params *plug_req = &peer->work_params.plug_req; struct fwtty_port *port; struct fwserial_mgmt_pkt *pkt; int rcode; pkt = kmalloc(sizeof(*pkt), GFP_KERNEL); if (!pkt) return; port = fwserial_find_port(peer); spin_lock_bh(&peer->lock); switch (peer->state) { case FWPS_NOT_ATTACHED: if (!port) { fwtty_err(&peer->unit, "no more ports avail\n"); fill_plug_rsp_nack(pkt); } else { peer->port = port; fill_plug_rsp_ok(pkt, peer->port); peer_set_state(peer, FWPS_PLUG_RESPONDING); /* don't release claimed port */ port = NULL; } break; case FWPS_PLUG_PENDING: if (peer->serial->card->guid > peer->guid) goto cleanup; /* We lost - hijack the already-claimed port and send ok */ del_timer(&peer->timer); fill_plug_rsp_ok(pkt, peer->port); peer_set_state(peer, FWPS_PLUG_RESPONDING); break; default: fill_plug_rsp_nack(pkt); } spin_unlock_bh(&peer->lock); if (port) fwserial_release_port(port, false); rcode = fwserial_send_mgmt_sync(peer, pkt); spin_lock_bh(&peer->lock); if (peer->state == FWPS_PLUG_RESPONDING) { if (rcode == RCODE_COMPLETE) { struct fwtty_port *tmp = peer->port; fwserial_virt_plug_complete(peer, plug_req); spin_unlock_bh(&peer->lock); fwtty_write_port_status(tmp); spin_lock_bh(&peer->lock); } else { fwtty_err(&peer->unit, "PLUG_RSP error (%d)\n", rcode); port = peer_revert_state(peer); } } cleanup: spin_unlock_bh(&peer->lock); if (port) fwserial_release_port(port, false); kfree(pkt); } static void fwserial_handle_unplug_req(struct work_struct *work) { struct fwtty_peer *peer = to_peer(work, work); struct fwtty_port *port = NULL; struct fwserial_mgmt_pkt *pkt; int rcode; pkt = kmalloc(sizeof(*pkt), GFP_KERNEL); if (!pkt) return; spin_lock_bh(&peer->lock); switch (peer->state) { case FWPS_ATTACHED: fill_unplug_rsp_ok(pkt); peer_set_state(peer, FWPS_UNPLUG_RESPONDING); break; case FWPS_UNPLUG_PENDING: if (peer->serial->card->guid > peer->guid) goto cleanup; /* We lost - send unplug rsp */ del_timer(&peer->timer); fill_unplug_rsp_ok(pkt); peer_set_state(peer, FWPS_UNPLUG_RESPONDING); break; default: fill_unplug_rsp_nack(pkt); } spin_unlock_bh(&peer->lock); rcode = fwserial_send_mgmt_sync(peer, pkt); spin_lock_bh(&peer->lock); if (peer->state == FWPS_UNPLUG_RESPONDING) { if (rcode != RCODE_COMPLETE) fwtty_err(&peer->unit, "UNPLUG_RSP error (%d)\n", rcode); port = peer_revert_state(peer); } cleanup: spin_unlock_bh(&peer->lock); if (port) fwserial_release_port(port, true); kfree(pkt); } static int fwserial_parse_mgmt_write(struct fwtty_peer *peer, struct fwserial_mgmt_pkt *pkt, unsigned long long addr, size_t len) { struct fwtty_port *port = NULL; bool reset = false; int rcode; if (addr != fwserial_mgmt_addr_handler.offset || len < sizeof(pkt->hdr)) return RCODE_ADDRESS_ERROR; if (len != be16_to_cpu(pkt->hdr.len) || len != mgmt_pkt_expected_len(pkt->hdr.code)) return RCODE_DATA_ERROR; spin_lock_bh(&peer->lock); if (peer->state == FWPS_GONE) { /* * This should never happen - it would mean that the * remote unit that just wrote this transaction was * already removed from the bus -- and the removal was * processed before we rec'd this transaction */ fwtty_err(&peer->unit, "peer already removed\n"); spin_unlock_bh(&peer->lock); return RCODE_ADDRESS_ERROR; } rcode = RCODE_COMPLETE; fwtty_dbg(&peer->unit, "mgmt: hdr.code: %04hx\n", pkt->hdr.code); switch (be16_to_cpu(pkt->hdr.code) & FWSC_CODE_MASK) { case FWSC_VIRT_CABLE_PLUG: if (work_pending(&peer->work)) { fwtty_err(&peer->unit, "plug req: busy\n"); rcode = RCODE_CONFLICT_ERROR; } else { peer->work_params.plug_req = pkt->plug_req; peer->workfn = fwserial_handle_plug_req; queue_work(system_unbound_wq, &peer->work); } break; case FWSC_VIRT_CABLE_PLUG_RSP: if (peer->state != FWPS_PLUG_PENDING) { rcode = RCODE_CONFLICT_ERROR; } else if (be16_to_cpu(pkt->hdr.code) & FWSC_RSP_NACK) { fwtty_notice(&peer->unit, "NACK plug rsp\n"); port = peer_revert_state(peer); } else { struct fwtty_port *tmp = peer->port; fwserial_virt_plug_complete(peer, &pkt->plug_rsp); spin_unlock_bh(&peer->lock); fwtty_write_port_status(tmp); spin_lock_bh(&peer->lock); } break; case FWSC_VIRT_CABLE_UNPLUG: if (work_pending(&peer->work)) { fwtty_err(&peer->unit, "unplug req: busy\n"); rcode = RCODE_CONFLICT_ERROR; } else { peer->workfn = fwserial_handle_unplug_req; queue_work(system_unbound_wq, &peer->work); } break; case FWSC_VIRT_CABLE_UNPLUG_RSP: if (peer->state != FWPS_UNPLUG_PENDING) { rcode = RCODE_CONFLICT_ERROR; } else { if (be16_to_cpu(pkt->hdr.code) & FWSC_RSP_NACK) fwtty_notice(&peer->unit, "NACK unplug?\n"); port = peer_revert_state(peer); reset = true; } break; default: fwtty_err(&peer->unit, "unknown mgmt code %d\n", be16_to_cpu(pkt->hdr.code)); rcode = RCODE_DATA_ERROR; } spin_unlock_bh(&peer->lock); if (port) fwserial_release_port(port, reset); return rcode; } /** * fwserial_mgmt_handler: bus address handler for mgmt requests * @parameters: fw_address_callback_t as specified by firewire core interface * * This handler is responsible for handling virtual cable requests from remotes * for all cards. */ static void fwserial_mgmt_handler(struct fw_card *card, struct fw_request *request, int tcode, int destination, int source, int generation, unsigned long long addr, void *data, size_t len, void *callback_data) { struct fwserial_mgmt_pkt *pkt = data; struct fwtty_peer *peer; int rcode; rcu_read_lock(); peer = __fwserial_peer_by_node_id(card, generation, source); if (!peer) { fwtty_dbg(card, "peer(%d:%x) not found\n", generation, source); __dump_peer_list(card); rcode = RCODE_CONFLICT_ERROR; } else { switch (tcode) { case TCODE_WRITE_BLOCK_REQUEST: rcode = fwserial_parse_mgmt_write(peer, pkt, addr, len); break; default: rcode = RCODE_TYPE_ERROR; } } rcu_read_unlock(); fw_send_response(card, request, rcode); } static int __init fwserial_init(void) { int err, num_loops = !!(create_loop_dev); /* XXX: placeholder for a "firewire" debugfs node */ fwserial_debugfs = debugfs_create_dir(KBUILD_MODNAME, NULL); /* num_ttys/num_ports must not be set above the static alloc avail */ if (num_ttys + num_loops > MAX_CARD_PORTS) num_ttys = MAX_CARD_PORTS - num_loops; num_ports = num_ttys + num_loops; fwtty_driver = tty_alloc_driver(MAX_TOTAL_PORTS, TTY_DRIVER_REAL_RAW | TTY_DRIVER_DYNAMIC_DEV); if (IS_ERR(fwtty_driver)) { err = PTR_ERR(fwtty_driver); goto remove_debugfs; } fwtty_driver->driver_name = KBUILD_MODNAME; fwtty_driver->name = tty_dev_name; fwtty_driver->major = 0; fwtty_driver->minor_start = 0; fwtty_driver->type = TTY_DRIVER_TYPE_SERIAL; fwtty_driver->subtype = SERIAL_TYPE_NORMAL; fwtty_driver->init_termios = tty_std_termios; fwtty_driver->init_termios.c_cflag |= CLOCAL; tty_set_operations(fwtty_driver, &fwtty_ops); err = tty_register_driver(fwtty_driver); if (err) { pr_err("register tty driver failed (%d)\n", err); goto put_tty; } if (create_loop_dev) { fwloop_driver = tty_alloc_driver(MAX_TOTAL_PORTS / num_ports, TTY_DRIVER_REAL_RAW | TTY_DRIVER_DYNAMIC_DEV); if (IS_ERR(fwloop_driver)) { err = PTR_ERR(fwloop_driver); goto unregister_driver; } fwloop_driver->driver_name = KBUILD_MODNAME "_loop"; fwloop_driver->name = loop_dev_name; fwloop_driver->major = 0; fwloop_driver->minor_start = 0; fwloop_driver->type = TTY_DRIVER_TYPE_SERIAL; fwloop_driver->subtype = SERIAL_TYPE_NORMAL; fwloop_driver->init_termios = tty_std_termios; fwloop_driver->init_termios.c_cflag |= CLOCAL; tty_set_operations(fwloop_driver, &fwloop_ops); err = tty_register_driver(fwloop_driver); if (err) { pr_err("register loop driver failed (%d)\n", err); goto put_loop; } } fwtty_txn_cache = kmem_cache_create("fwtty_txn_cache", sizeof(struct fwtty_transaction), 0, 0, NULL); if (!fwtty_txn_cache) { err = -ENOMEM; goto unregister_loop; } /* * Ideally, this address handler would be registered per local node * (rather than the same handler for all local nodes). However, * since the firewire core requires the config rom descriptor *before* * the local unit device(s) are created, a single management handler * must suffice for all local serial units. */ fwserial_mgmt_addr_handler.length = sizeof(struct fwserial_mgmt_pkt); fwserial_mgmt_addr_handler.address_callback = fwserial_mgmt_handler; err = fw_core_add_address_handler(&fwserial_mgmt_addr_handler, &fwserial_mgmt_addr_region); if (err) { pr_err("add management handler failed (%d)\n", err); goto destroy_cache; } fwserial_unit_directory_data.unit_addr_offset = FW_UNIT_ADDRESS(fwserial_mgmt_addr_handler.offset); err = fw_core_add_descriptor(&fwserial_unit_directory); if (err) { pr_err("add unit descriptor failed (%d)\n", err); goto remove_handler; } err = driver_register(&fwserial_driver.driver); if (err) { pr_err("register fwserial driver failed (%d)\n", err); goto remove_descriptor; } return 0; remove_descriptor: fw_core_remove_descriptor(&fwserial_unit_directory); remove_handler: fw_core_remove_address_handler(&fwserial_mgmt_addr_handler); destroy_cache: kmem_cache_destroy(fwtty_txn_cache); unregister_loop: if (create_loop_dev) tty_unregister_driver(fwloop_driver); put_loop: if (create_loop_dev) put_tty_driver(fwloop_driver); unregister_driver: tty_unregister_driver(fwtty_driver); put_tty: put_tty_driver(fwtty_driver); remove_debugfs: debugfs_remove_recursive(fwserial_debugfs); return err; } static void __exit fwserial_exit(void) { driver_unregister(&fwserial_driver.driver); fw_core_remove_descriptor(&fwserial_unit_directory); fw_core_remove_address_handler(&fwserial_mgmt_addr_handler); kmem_cache_destroy(fwtty_txn_cache); if (create_loop_dev) { tty_unregister_driver(fwloop_driver); put_tty_driver(fwloop_driver); } tty_unregister_driver(fwtty_driver); put_tty_driver(fwtty_driver); debugfs_remove_recursive(fwserial_debugfs); } module_init(fwserial_init); module_exit(fwserial_exit); MODULE_AUTHOR("Peter Hurley (peter@hurleysoftware.com)"); MODULE_DESCRIPTION("FireWire Serial TTY Driver"); MODULE_LICENSE("GPL"); MODULE_DEVICE_TABLE(ieee1394, fwserial_id_table); MODULE_PARM_DESC(ttys, "Number of ttys to create for each local firewire node"); MODULE_PARM_DESC(auto, "Auto-connect a tty to each firewire node discovered"); MODULE_PARM_DESC(loop, "Create a loopback device, fwloop<n>, with ttys");
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