diff options
Diffstat (limited to 'drivers/tty/n_gsm.c')
| -rw-r--r-- | drivers/tty/n_gsm.c | 473 |
1 files changed, 416 insertions, 57 deletions
diff --git a/drivers/tty/n_gsm.c b/drivers/tty/n_gsm.c index 5e516f5cac5a..daf12132deb1 100644 --- a/drivers/tty/n_gsm.c +++ b/drivers/tty/n_gsm.c @@ -38,8 +38,10 @@ #include <linux/sched/signal.h> #include <linux/interrupt.h> #include <linux/tty.h> +#include <linux/bitfield.h> #include <linux/ctype.h> #include <linux/mm.h> +#include <linux/math.h> #include <linux/string.h> #include <linux/slab.h> #include <linux/poll.h> @@ -75,7 +77,12 @@ module_param(debug, int, 0600); #define T1 10 /* 100mS */ #define T2 34 /* 333mS */ +#define T3 10 /* 10s */ #define N2 3 /* Retry 3 times */ +#define K 2 /* outstanding I frames */ + +#define MAX_T3 255 /* In seconds. */ +#define MAX_WINDOW_SIZE 7 /* Limit of K in error recovery mode. */ /* Use long timers for testing at low speed with debug on */ #ifdef DEBUG_TIMING @@ -89,6 +96,7 @@ module_param(debug, int, 0600); */ #define MAX_MRU 1500 #define MAX_MTU 1500 +#define MIN_MTU (PROT_OVERHEAD + 1) /* SOF, ADDR, CTRL, LEN1, LEN2, ..., FCS, EOF */ #define PROT_OVERHEAD 7 #define GSM_NET_TX_TIMEOUT (HZ*10) @@ -120,6 +128,7 @@ struct gsm_msg { enum gsm_dlci_state { DLCI_CLOSED, + DLCI_CONFIGURE, /* Sending PN (for adaption > 1) */ DLCI_OPENING, /* Sending SABM not seen UA */ DLCI_OPEN, /* SABM/UA complete */ DLCI_CLOSING, /* Sending DISC not seen UA/DM */ @@ -159,7 +168,12 @@ struct gsm_dlci { int prev_adaption; u32 modem_rx; /* Our incoming virtual modem lines */ u32 modem_tx; /* Our outgoing modem lines */ + unsigned int mtu; bool dead; /* Refuse re-open */ + /* Configuration */ + u8 prio; /* Priority */ + u8 ftype; /* Frame type */ + u8 k; /* Window size */ /* Flow control */ bool throttled; /* Private copy of throttle state */ bool constipated; /* Throttle status for outgoing */ @@ -172,6 +186,32 @@ struct gsm_dlci { struct net_device *net; /* network interface, if created */ }; +/* + * Parameter bits used for parameter negotiation according to 3GPP 27.010 + * chapter 5.4.6.3.1. + */ + +struct gsm_dlci_param_bits { + u8 d_bits; + u8 i_cl_bits; + u8 p_bits; + u8 t_bits; + __le16 n_bits; + u8 na_bits; + u8 k_bits; +}; + +static_assert(sizeof(struct gsm_dlci_param_bits) == 8); + +#define PN_D_FIELD_DLCI GENMASK(5, 0) +#define PN_I_CL_FIELD_FTYPE GENMASK(3, 0) +#define PN_I_CL_FIELD_ADAPTION GENMASK(7, 4) +#define PN_P_FIELD_PRIO GENMASK(5, 0) +#define PN_T_FIELD_T1 GENMASK(7, 0) +#define PN_N_FIELD_N1 GENMASK(15, 0) +#define PN_NA_FIELD_N2 GENMASK(7, 0) +#define PN_K_FIELD_K GENMASK(2, 0) + /* Total number of supported devices */ #define GSM_TTY_MINORS 256 @@ -264,7 +304,7 @@ struct gsm_mux { bool constipated; /* Asked by remote to shut up */ bool has_devices; /* Devices were registered */ - struct mutex tx_mutex; + spinlock_t tx_lock; unsigned int tx_bytes; /* TX data outstanding */ #define TX_THRESH_HI 8192 #define TX_THRESH_LO 2048 @@ -272,7 +312,7 @@ struct gsm_mux { struct list_head tx_data_list; /* Pending data packets */ /* Control messages */ - struct delayed_work kick_timeout; /* Kick TX queuing on timeout */ + struct timer_list kick_timer; /* Kick TX queuing on timeout */ struct timer_list t2_timer; /* Retransmit timer for commands */ int cretries; /* Command retry counter */ struct gsm_control *pending_cmd;/* Our current pending command */ @@ -282,7 +322,9 @@ struct gsm_mux { int adaption; /* 1 or 2 supported */ u8 ftype; /* UI or UIH */ int t1, t2; /* Timers in 1/100th of a sec */ + unsigned int t3; /* Power wake-up timer in seconds. */ int n2; /* Retry count */ + u8 k; /* Window size */ /* Statistics (not currently exposed) */ unsigned long bad_fcs; @@ -397,6 +439,7 @@ static const u8 gsm_fcs8[256] = { #define INIT_FCS 0xFF #define GOOD_FCS 0xCF +static void gsm_dlci_close(struct gsm_dlci *dlci); static int gsmld_output(struct gsm_mux *gsm, u8 *data, int len); static int gsm_modem_update(struct gsm_dlci *dlci, u8 brk); static struct gsm_msg *gsm_data_alloc(struct gsm_mux *gsm, u8 addr, int len, @@ -520,6 +563,57 @@ static void gsm_hex_dump_bytes(const char *fname, const u8 *data, } /** + * gsm_encode_params - encode DLCI parameters + * @dlci: DLCI to encode from + * @params: buffer to fill with the encoded parameters + * + * Encodes the parameters according to GSM 07.10 section 5.4.6.3.1 + * table 3. + */ +static int gsm_encode_params(const struct gsm_dlci *dlci, + struct gsm_dlci_param_bits *params) +{ + const struct gsm_mux *gsm = dlci->gsm; + unsigned int i, cl; + + switch (dlci->ftype) { + case UIH: + i = 0; /* UIH */ + break; + case UI: + i = 1; /* UI */ + break; + default: + pr_debug("unsupported frame type %d\n", dlci->ftype); + return -EINVAL; + } + + switch (dlci->adaption) { + case 1: /* Unstructured */ + cl = 0; /* convergence layer type 1 */ + break; + case 2: /* Unstructured with modem bits. */ + cl = 1; /* convergence layer type 2 */ + break; + default: + pr_debug("unsupported adaption %d\n", dlci->adaption); + return -EINVAL; + } + + params->d_bits = FIELD_PREP(PN_D_FIELD_DLCI, dlci->addr); + /* UIH, convergence layer type 1 */ + params->i_cl_bits = FIELD_PREP(PN_I_CL_FIELD_FTYPE, i) | + FIELD_PREP(PN_I_CL_FIELD_ADAPTION, cl); + params->p_bits = FIELD_PREP(PN_P_FIELD_PRIO, dlci->prio); + params->t_bits = FIELD_PREP(PN_T_FIELD_T1, gsm->t1); + params->n_bits = cpu_to_le16(FIELD_PREP(PN_N_FIELD_N1, dlci->mtu)); + params->na_bits = FIELD_PREP(PN_NA_FIELD_N2, gsm->n2); + params->k_bits = FIELD_PREP(PN_K_FIELD_K, dlci->k); + + return 0; +} + +/** * gsm_register_devices - register all tty devices for a given mux index * * @driver: the tty driver that describes the tty devices @@ -700,6 +794,7 @@ static int gsm_send(struct gsm_mux *gsm, int addr, int cr, int control) struct gsm_msg *msg; u8 *dp; int ocr; + unsigned long flags; msg = gsm_data_alloc(gsm, addr, 0, control); if (!msg) @@ -721,10 +816,10 @@ static int gsm_send(struct gsm_mux *gsm, int addr, int cr, int control) gsm_print_packet("Q->", addr, cr, control, NULL, 0); - mutex_lock(&gsm->tx_mutex); + spin_lock_irqsave(&gsm->tx_lock, flags); list_add_tail(&msg->list, &gsm->tx_ctrl_list); gsm->tx_bytes += msg->len; - mutex_unlock(&gsm->tx_mutex); + spin_unlock_irqrestore(&gsm->tx_lock, flags); gsmld_write_trigger(gsm); return 0; @@ -749,7 +844,7 @@ static void gsm_dlci_clear_queues(struct gsm_mux *gsm, struct gsm_dlci *dlci) spin_unlock_irqrestore(&dlci->lock, flags); /* Clear data packets in MUX write queue */ - mutex_lock(&gsm->tx_mutex); + spin_lock_irqsave(&gsm->tx_lock, flags); list_for_each_entry_safe(msg, nmsg, &gsm->tx_data_list, list) { if (msg->addr != addr) continue; @@ -757,7 +852,7 @@ static void gsm_dlci_clear_queues(struct gsm_mux *gsm, struct gsm_dlci *dlci) list_del(&msg->list); kfree(msg); } - mutex_unlock(&gsm->tx_mutex); + spin_unlock_irqrestore(&gsm->tx_lock, flags); } /** @@ -1028,7 +1123,7 @@ static void __gsm_data_queue(struct gsm_dlci *dlci, struct gsm_msg *msg) gsm->tx_bytes += msg->len; gsmld_write_trigger(gsm); - schedule_delayed_work(&gsm->kick_timeout, 10 * gsm->t1 * HZ / 100); + mod_timer(&gsm->kick_timer, jiffies + 10 * gsm->t1 * HZ / 100); } /** @@ -1043,9 +1138,10 @@ static void __gsm_data_queue(struct gsm_dlci *dlci, struct gsm_msg *msg) static void gsm_data_queue(struct gsm_dlci *dlci, struct gsm_msg *msg) { - mutex_lock(&dlci->gsm->tx_mutex); + unsigned long flags; + spin_lock_irqsave(&dlci->gsm->tx_lock, flags); __gsm_data_queue(dlci, msg); - mutex_unlock(&dlci->gsm->tx_mutex); + spin_unlock_irqrestore(&dlci->gsm->tx_lock, flags); } /** @@ -1057,7 +1153,7 @@ static void gsm_data_queue(struct gsm_dlci *dlci, struct gsm_msg *msg) * is data. Keep to the MRU of the mux. This path handles the usual tty * interface which is a byte stream with optional modem data. * - * Caller must hold the tx_mutex of the mux. + * Caller must hold the tx_lock of the mux. */ static int gsm_dlci_data_output(struct gsm_mux *gsm, struct gsm_dlci *dlci) @@ -1074,12 +1170,12 @@ static int gsm_dlci_data_output(struct gsm_mux *gsm, struct gsm_dlci *dlci) return 0; /* MTU/MRU count only the data bits but watch adaption mode */ - if ((len + h) > gsm->mtu) - len = gsm->mtu - h; + if ((len + h) > dlci->mtu) + len = dlci->mtu - h; size = len + h; - msg = gsm_data_alloc(gsm, dlci->addr, size, gsm->ftype); + msg = gsm_data_alloc(gsm, dlci->addr, size, dlci->ftype); if (!msg) return -ENOMEM; dp = msg->data; @@ -1117,7 +1213,7 @@ static int gsm_dlci_data_output(struct gsm_mux *gsm, struct gsm_dlci *dlci) * is data. Keep to the MRU of the mux. This path handles framed data * queued as skbuffs to the DLCI. * - * Caller must hold the tx_mutex of the mux. + * Caller must hold the tx_lock of the mux. */ static int gsm_dlci_data_output_framed(struct gsm_mux *gsm, @@ -1133,7 +1229,7 @@ static int gsm_dlci_data_output_framed(struct gsm_mux *gsm, if (dlci->adaption == 4) overhead = 1; - /* dlci->skb is locked by tx_mutex */ + /* dlci->skb is locked by tx_lock */ if (dlci->skb == NULL) { dlci->skb = skb_dequeue_tail(&dlci->skb_list); if (dlci->skb == NULL) @@ -1143,19 +1239,19 @@ static int gsm_dlci_data_output_framed(struct gsm_mux *gsm, len = dlci->skb->len + overhead; /* MTU/MRU count only the data bits */ - if (len > gsm->mtu) { + if (len > dlci->mtu) { if (dlci->adaption == 3) { /* Over long frame, bin it */ dev_kfree_skb_any(dlci->skb); dlci->skb = NULL; return 0; } - len = gsm->mtu; + len = dlci->mtu; } else last = 1; size = len + overhead; - msg = gsm_data_alloc(gsm, dlci->addr, size, gsm->ftype); + msg = gsm_data_alloc(gsm, dlci->addr, size, dlci->ftype); if (msg == NULL) { skb_queue_tail(&dlci->skb_list, dlci->skb); dlci->skb = NULL; @@ -1187,7 +1283,7 @@ static int gsm_dlci_data_output_framed(struct gsm_mux *gsm, * Push an empty frame in to the transmit queue to update the modem status * bits and to transmit an optional break. * - * Caller must hold the tx_mutex of the mux. + * Caller must hold the tx_lock of the mux. */ static int gsm_dlci_modem_output(struct gsm_mux *gsm, struct gsm_dlci *dlci, @@ -1212,7 +1308,7 @@ static int gsm_dlci_modem_output(struct gsm_mux *gsm, struct gsm_dlci *dlci, return -EINVAL; } - msg = gsm_data_alloc(gsm, dlci->addr, size, gsm->ftype); + msg = gsm_data_alloc(gsm, dlci->addr, size, dlci->ftype); if (!msg) { pr_err("%s: gsm_data_alloc error", __func__); return -ENOMEM; @@ -1285,7 +1381,7 @@ static int gsm_dlci_data_sweep(struct gsm_mux *gsm) } if (!sent) break; - }; + } return ret; } @@ -1301,12 +1397,13 @@ static int gsm_dlci_data_sweep(struct gsm_mux *gsm) static void gsm_dlci_data_kick(struct gsm_dlci *dlci) { + unsigned long flags; int sweep; if (dlci->constipated) return; - mutex_lock(&dlci->gsm->tx_mutex); + spin_lock_irqsave(&dlci->gsm->tx_lock, flags); /* If we have nothing running then we need to fire up */ sweep = (dlci->gsm->tx_bytes < TX_THRESH_LO); if (dlci->gsm->tx_bytes == 0) { @@ -1317,7 +1414,7 @@ static void gsm_dlci_data_kick(struct gsm_dlci *dlci) } if (sweep) gsm_dlci_data_sweep(dlci->gsm); - mutex_unlock(&dlci->gsm->tx_mutex); + spin_unlock_irqrestore(&dlci->gsm->tx_lock, flags); } /* @@ -1337,8 +1434,9 @@ static void gsm_dlci_data_kick(struct gsm_dlci *dlci) static int gsm_control_command(struct gsm_mux *gsm, int cmd, const u8 *data, int dlen) { - struct gsm_msg *msg = gsm_data_alloc(gsm, 0, dlen + 2, gsm->ftype); + struct gsm_msg *msg; + msg = gsm_data_alloc(gsm, 0, dlen + 2, gsm->dlci[0]->ftype); if (msg == NULL) return -ENOMEM; @@ -1364,7 +1462,8 @@ static void gsm_control_reply(struct gsm_mux *gsm, int cmd, const u8 *data, int dlen) { struct gsm_msg *msg; - msg = gsm_data_alloc(gsm, 0, dlen + 2, gsm->ftype); + + msg = gsm_data_alloc(gsm, 0, dlen + 2, gsm->dlci[0]->ftype); if (msg == NULL) return; msg->data[0] = (cmd & 0xFE) << 1 | EA; /* Clear C/R */ @@ -1435,6 +1534,116 @@ static void gsm_process_modem(struct tty_struct *tty, struct gsm_dlci *dlci, } /** + * gsm_process_negotiation - process received parameters + * @gsm: GSM channel + * @addr: DLCI address + * @cr: command/response + * @params: encoded parameters from the parameter negotiation message + * + * Used when the response for our parameter negotiation command was + * received. + */ +static int gsm_process_negotiation(struct gsm_mux *gsm, unsigned int addr, + unsigned int cr, + const struct gsm_dlci_param_bits *params) +{ + struct gsm_dlci *dlci = gsm->dlci[addr]; + unsigned int ftype, i, adaption, prio, n1, k; + + i = FIELD_GET(PN_I_CL_FIELD_FTYPE, params->i_cl_bits); + adaption = FIELD_GET(PN_I_CL_FIELD_ADAPTION, params->i_cl_bits) + 1; + prio = FIELD_GET(PN_P_FIELD_PRIO, params->p_bits); + n1 = FIELD_GET(PN_N_FIELD_N1, get_unaligned_le16(¶ms->n_bits)); + k = FIELD_GET(PN_K_FIELD_K, params->k_bits); + + if (n1 < MIN_MTU) { + if (debug & DBG_ERRORS) + pr_info("%s N1 out of range in PN\n", __func__); + return -EINVAL; + } + + switch (i) { + case 0x00: + ftype = UIH; + break; + case 0x01: + ftype = UI; + break; + case 0x02: /* I frames are not supported */ + if (debug & DBG_ERRORS) + pr_info("%s unsupported I frame request in PN\n", + __func__); + return -EINVAL; + default: + if (debug & DBG_ERRORS) + pr_info("%s i out of range in PN\n", __func__); + return -EINVAL; + } + + if (!cr && gsm->initiator) { + if (adaption != dlci->adaption) { + if (debug & DBG_ERRORS) + pr_info("%s invalid adaption %d in PN\n", + __func__, adaption); + return -EINVAL; + } + if (prio != dlci->prio) { + if (debug & DBG_ERRORS) + pr_info("%s invalid priority %d in PN", + __func__, prio); + return -EINVAL; + } + if (n1 > gsm->mru || n1 > dlci->mtu) { + /* We requested a frame size but the other party wants + * to send larger frames. The standard allows only a + * smaller response value than requested (5.4.6.3.1). + */ + if (debug & DBG_ERRORS) + pr_info("%s invalid N1 %d in PN\n", __func__, + n1); + return -EINVAL; + } + dlci->mtu = n1; + if (ftype != dlci->ftype) { + if (debug & DBG_ERRORS) + pr_info("%s invalid i %d in PN\n", __func__, i); + return -EINVAL; + } + if (ftype != UI && ftype != UIH && k > dlci->k) { + if (debug & DBG_ERRORS) + pr_info("%s invalid k %d in PN\n", __func__, k); + return -EINVAL; + } + dlci->k = k; + } else if (cr && !gsm->initiator) { + /* Only convergence layer type 1 and 2 are supported. */ + if (adaption != 1 && adaption != 2) { + if (debug & DBG_ERRORS) + pr_info("%s invalid adaption %d in PN\n", + __func__, adaption); + return -EINVAL; + } + dlci->adaption = adaption; + if (n1 > gsm->mru) { + /* Propose a smaller value */ + dlci->mtu = gsm->mru; + } else if (n1 > MAX_MTU) { + /* Propose a smaller value */ + dlci->mtu = MAX_MTU; + } else { + dlci->mtu = n1; + } + dlci->prio = prio; + dlci->ftype = ftype; + dlci->k = k; + } else { + return -EINVAL; + } + + return 0; +} + +/** * gsm_control_modem - modem status received * @gsm: GSM channel * @data: data following command @@ -1488,6 +1697,65 @@ static void gsm_control_modem(struct gsm_mux *gsm, const u8 *data, int clen) } /** + * gsm_control_negotiation - parameter negotiation received + * @gsm: GSM channel + * @cr: command/response flag + * @data: data following command + * @dlen: data length + * + * We have received a parameter negotiation message. This is used by + * the GSM mux protocol to configure protocol parameters for a new DLCI. + */ +static void gsm_control_negotiation(struct gsm_mux *gsm, unsigned int cr, + const u8 *data, unsigned int dlen) +{ + unsigned int addr; + struct gsm_dlci_param_bits pn_reply; + struct gsm_dlci *dlci; + struct gsm_dlci_param_bits *params; + + if (dlen < sizeof(struct gsm_dlci_param_bits)) + return; + + /* Invalid DLCI? */ + params = (struct gsm_dlci_param_bits *)data; + addr = FIELD_GET(PN_D_FIELD_DLCI, params->d_bits); + if (addr == 0 || addr >= NUM_DLCI || !gsm->dlci[addr]) + return; + dlci = gsm->dlci[addr]; + + /* Too late for parameter negotiation? */ + if ((!cr && dlci->state == DLCI_OPENING) || dlci->state == DLCI_OPEN) + return; + + /* Process the received parameters */ + if (gsm_process_negotiation(gsm, addr, cr, params) != 0) { + /* Negotiation failed. Close the link. */ + if (debug & DBG_ERRORS) + pr_info("%s PN failed\n", __func__); + gsm_dlci_close(dlci); + return; + } + + if (cr) { + /* Reply command with accepted parameters. */ + if (gsm_encode_params(dlci, &pn_reply) == 0) + gsm_control_reply(gsm, CMD_PN, (const u8 *)&pn_reply, + sizeof(pn_reply)); + else if (debug & DBG_ERRORS) + pr_info("%s PN invalid\n", __func__); + } else if (dlci->state == DLCI_CONFIGURE) { + /* Proceed with link setup by sending SABM before UA */ + dlci->state = DLCI_OPENING; + gsm_command(gsm, dlci->addr, SABM|PF); + mod_timer(&dlci->t1, jiffies + gsm->t1 * HZ / 100); + } else { + if (debug & DBG_ERRORS) + pr_info("%s PN in invalid state\n", __func__); + } +} + +/** * gsm_control_rls - remote line status * @gsm: GSM channel * @data: data bytes @@ -1596,8 +1864,12 @@ static void gsm_control_message(struct gsm_mux *gsm, unsigned int command, /* Modem wishes to enter power saving state */ gsm_control_reply(gsm, CMD_PSC, NULL, 0); break; + /* Optional commands */ + case CMD_PN: + /* Modem sends a parameter negotiation command */ + gsm_control_negotiation(gsm, 1, data, clen); + break; /* Optional unsupported commands */ - case CMD_PN: /* Parameter negotiation */ case CMD_RPN: /* Remote port negotiation */ case CMD_SNC: /* Service negotiation command */ default: @@ -1630,8 +1902,8 @@ static void gsm_control_response(struct gsm_mux *gsm, unsigned int command, spin_lock_irqsave(&gsm->control_lock, flags); ctrl = gsm->pending_cmd; - /* Does the reply match our command */ command |= 1; + /* Does the reply match our command */ if (ctrl != NULL && (command == ctrl->cmd || command == CMD_NSC)) { /* Our command was replied to, kill the retry timer */ del_timer(&gsm->t2_timer); @@ -1641,6 +1913,9 @@ static void gsm_control_response(struct gsm_mux *gsm, unsigned int command, ctrl->error = -EOPNOTSUPP; ctrl->done = 1; wake_up(&gsm->event); + /* Or did we receive the PN response to our PN command */ + } else if (command == CMD_PN) { + gsm_control_negotiation(gsm, 0, data, clen); } spin_unlock_irqrestore(&gsm->control_lock, flags); } @@ -1708,7 +1983,7 @@ static struct gsm_control *gsm_control_send(struct gsm_mux *gsm, unsigned int command, u8 *data, int clen) { struct gsm_control *ctrl = kzalloc(sizeof(struct gsm_control), - GFP_KERNEL); + GFP_ATOMIC); unsigned long flags; if (ctrl == NULL) return NULL; @@ -1819,6 +2094,32 @@ static void gsm_dlci_open(struct gsm_dlci *dlci) } /** + * gsm_dlci_negotiate - start parameter negotiation + * @dlci: DLCI to open + * + * Starts the parameter negotiation for the new DLCI. This needs to be done + * before the DLCI initialized the channel via SABM. + */ +static int gsm_dlci_negotiate(struct gsm_dlci *dlci) +{ + struct gsm_mux *gsm = dlci->gsm; + struct gsm_dlci_param_bits params; + int ret; + + ret = gsm_encode_params(dlci, ¶ms); + if (ret != 0) + return ret; + + /* We cannot asynchronous wait for the command response with + * gsm_command() and gsm_control_wait() at this point. + */ + ret = gsm_control_command(gsm, CMD_PN, (const u8 *)¶ms, + sizeof(params)); + + return ret; +} + +/** * gsm_dlci_t1 - T1 timer expiry * @t: timer contained in the DLCI that opened * @@ -1839,6 +2140,14 @@ static void gsm_dlci_t1(struct timer_list *t) struct gsm_mux *gsm = dlci->gsm; switch (dlci->state) { + case DLCI_CONFIGURE: + if (dlci->retries && gsm_dlci_negotiate(dlci) == 0) { + dlci->retries--; + mod_timer(&dlci->t1, jiffies + gsm->t1 * HZ / 100); + } else { + gsm_dlci_begin_close(dlci); /* prevent half open link */ + } + break; case DLCI_OPENING: if (dlci->retries) { dlci->retries--; @@ -1877,17 +2186,46 @@ static void gsm_dlci_t1(struct timer_list *t) * to the modem which should then reply with a UA or ADM, at which point * we will move into open state. Opening is done asynchronously with retry * running off timers and the responses. + * Parameter negotiation is performed before SABM if required. */ static void gsm_dlci_begin_open(struct gsm_dlci *dlci) { - struct gsm_mux *gsm = dlci->gsm; - if (dlci->state == DLCI_OPEN || dlci->state == DLCI_OPENING) + struct gsm_mux *gsm = dlci ? dlci->gsm : NULL; + bool need_pn = false; + + if (!gsm) return; - dlci->retries = gsm->n2; - dlci->state = DLCI_OPENING; - gsm_command(dlci->gsm, dlci->addr, SABM|PF); - mod_timer(&dlci->t1, jiffies + gsm->t1 * HZ / 100); + + if (dlci->addr != 0) { + if (gsm->adaption != 1 || gsm->adaption != dlci->adaption) + need_pn = true; + if (dlci->prio != (roundup(dlci->addr + 1, 8) - 1)) + need_pn = true; + if (gsm->ftype != dlci->ftype) + need_pn = true; + } + + switch (dlci->state) { + case DLCI_CLOSED: + case DLCI_CLOSING: + dlci->retries = gsm->n2; + if (!need_pn) { + dlci->state = DLCI_OPENING; + gsm_command(gsm, dlci->addr, SABM|PF); + } else { + /* Configure DLCI before setup */ + dlci->state = DLCI_CONFIGURE; + if (gsm_dlci_negotiate(dlci) != 0) { + gsm_dlci_close(dlci); + return; + } + } + mod_timer(&dlci->t1, jiffies + gsm->t1 * HZ / 100); + break; + default: + break; + } } /** @@ -2019,23 +2357,24 @@ static void gsm_dlci_command(struct gsm_dlci *dlci, const u8 *data, int len) } /** - * gsm_kick_timeout - transmit if possible - * @work: work contained in our gsm object + * gsm_kick_timer - transmit if possible + * @t: timer contained in our gsm object * * Transmit data from DLCIs if the queue is empty. We can't rely on * a tty wakeup except when we filled the pipe so we need to fire off * new data ourselves in other cases. */ -static void gsm_kick_timeout(struct work_struct *work) +static void gsm_kick_timer(struct timer_list *t) { - struct gsm_mux *gsm = container_of(work, struct gsm_mux, kick_timeout.work); + struct gsm_mux *gsm = from_timer(gsm, t, kick_timer); + unsigned long flags; int sent = 0; - mutex_lock(&gsm->tx_mutex); + spin_lock_irqsave(&gsm->tx_lock, flags); /* If we have nothing running then we need to fire up */ if (gsm->tx_bytes < TX_THRESH_LO) sent = gsm_dlci_data_sweep(gsm); - mutex_unlock(&gsm->tx_mutex); + spin_unlock_irqrestore(&gsm->tx_lock, flags); if (sent && debug & DBG_DATA) pr_info("%s TX queue stalled\n", __func__); @@ -2074,6 +2413,13 @@ static struct gsm_dlci *gsm_dlci_alloc(struct gsm_mux *gsm, int addr) dlci->gsm = gsm; dlci->addr = addr; dlci->adaption = gsm->adaption; + dlci->mtu = gsm->mtu; + if (addr == 0) + dlci->prio = 0; + else + dlci->prio = roundup(addr + 1, 8) - 1; + dlci->ftype = gsm->ftype; + dlci->k = gsm->k; dlci->state = DLCI_CLOSED; if (addr) { dlci->data = gsm_dlci_data; @@ -2492,7 +2838,7 @@ static void gsm_cleanup_mux(struct gsm_mux *gsm, bool disc) } /* Finish outstanding timers, making sure they are done */ - cancel_delayed_work_sync(&gsm->kick_timeout); + del_timer_sync(&gsm->kick_timer); del_timer_sync(&gsm->t2_timer); /* Finish writing to ldisc */ @@ -2565,7 +2911,6 @@ static void gsm_free_mux(struct gsm_mux *gsm) break; } } - mutex_destroy(&gsm->tx_mutex); mutex_destroy(&gsm->mutex); kfree(gsm->txframe); kfree(gsm->buf); @@ -2637,19 +2982,21 @@ static struct gsm_mux *gsm_alloc_mux(void) } spin_lock_init(&gsm->lock); mutex_init(&gsm->mutex); - mutex_init(&gsm->tx_mutex); kref_init(&gsm->ref); INIT_LIST_HEAD(&gsm->tx_ctrl_list); INIT_LIST_HEAD(&gsm->tx_data_list); - INIT_DELAYED_WORK(&gsm->kick_timeout, gsm_kick_timeout); + timer_setup(&gsm->kick_timer, gsm_kick_timer, 0); timer_setup(&gsm->t2_timer, gsm_control_retransmit, 0); INIT_WORK(&gsm->tx_work, gsmld_write_task); init_waitqueue_head(&gsm->event); spin_lock_init(&gsm->control_lock); + spin_lock_init(&gsm->tx_lock); gsm->t1 = T1; gsm->t2 = T2; + gsm->t3 = T3; gsm->n2 = N2; + gsm->k = K; gsm->ftype = UIH; gsm->adaption = 1; gsm->encoding = GSM_ADV_OPT; @@ -2670,7 +3017,6 @@ static struct gsm_mux *gsm_alloc_mux(void) } spin_unlock(&gsm_mux_lock); if (i == MAX_MUX) { - mutex_destroy(&gsm->tx_mutex); mutex_destroy(&gsm->mutex); kfree(gsm->txframe); kfree(gsm->buf); @@ -2690,7 +3036,7 @@ static void gsm_copy_config_values(struct gsm_mux *gsm, c->initiator = gsm->initiator; c->t1 = gsm->t1; c->t2 = gsm->t2; - c->t3 = 0; /* Not supported */ + c->t3 = gsm->t3; c->n2 = gsm->n2; if (gsm->ftype == UIH) c->i = 1; @@ -2699,7 +3045,7 @@ static void gsm_copy_config_values(struct gsm_mux *gsm, pr_debug("Ftype %d i %d\n", gsm->ftype, c->i); c->mru = gsm->mru; c->mtu = gsm->mtu; - c->k = 0; + c->k = gsm->k; } static int gsm_config(struct gsm_mux *gsm, struct gsm_config *c) @@ -2712,7 +3058,11 @@ static int gsm_config(struct gsm_mux *gsm, struct gsm_config *c) if ((c->adaption != 1 && c->adaption != 2) || c->k) return -EOPNOTSUPP; /* Check the MRU/MTU range looks sane */ - if (c->mru > MAX_MRU || c->mtu > MAX_MTU || c->mru < 8 || c->mtu < 8) + if (c->mru < MIN_MTU || c->mtu < MIN_MTU) + return -EINVAL; + if (c->mru > MAX_MRU || c->mtu > MAX_MTU) + return -EINVAL; + if (c->t3 > MAX_T3) return -EINVAL; if (c->n2 > 255) return -EINVAL; @@ -2720,6 +3070,8 @@ static int gsm_config(struct gsm_mux *gsm, struct gsm_config *c) return -EINVAL; if (c->initiator > 1) return -EINVAL; + if (c->k > MAX_WINDOW_SIZE) + return -EINVAL; if (c->i == 0 || c->i > 2) /* UIH and UI only */ return -EINVAL; /* @@ -2767,6 +3119,10 @@ static int gsm_config(struct gsm_mux *gsm, struct gsm_config *c) gsm->t1 = c->t1; if (c->t2) gsm->t2 = c->t2; + if (c->t3) + gsm->t3 = c->t3; + if (c->k) + gsm->k = c->k; /* * FIXME: We need to separate activation/deactivation from adding @@ -2826,16 +3182,17 @@ static void gsmld_write_trigger(struct gsm_mux *gsm) static void gsmld_write_task(struct work_struct *work) { struct gsm_mux *gsm = container_of(work, struct gsm_mux, tx_work); + unsigned long flags; int i, ret; /* All outstanding control channel and control messages and one data * frame is sent. */ ret = -ENODEV; - mutex_lock(&gsm->tx_mutex); + spin_lock_irqsave(&gsm->tx_lock, flags); if (gsm->tty) ret = gsm_data_kick(gsm); - mutex_unlock(&gsm->tx_mutex); + spin_unlock_irqrestore(&gsm->tx_lock, flags); if (ret >= 0) for (i = 0; i < NUM_DLCI; i++) @@ -3042,6 +3399,7 @@ static ssize_t gsmld_write(struct tty_struct *tty, struct file *file, const unsigned char *buf, size_t nr) { struct gsm_mux *gsm = tty->disc_data; + unsigned long flags; int space; int ret; @@ -3049,13 +3407,13 @@ static ssize_t gsmld_write(struct tty_struct *tty, struct file *file, return -ENODEV; ret = -ENOBUFS; - mutex_lock(&gsm->tx_mutex); + spin_lock_irqsave(&gsm->tx_lock, flags); space = tty_write_room(tty); if (space >= nr) ret = tty->ops->write(tty, buf, nr); else set_bit(TTY_DO_WRITE_WAKEUP, &tty->flags); - mutex_unlock(&gsm->tx_mutex); + spin_unlock_irqrestore(&gsm->tx_lock, flags); return ret; } @@ -3295,9 +3653,9 @@ static int gsm_create_network(struct gsm_dlci *dlci, struct gsm_netconfig *nc) pr_err("alloc_netdev failed\n"); return -ENOMEM; } - net->mtu = dlci->gsm->mtu; - net->min_mtu = 8; - net->max_mtu = dlci->gsm->mtu; + net->mtu = dlci->mtu; + net->min_mtu = MIN_MTU; + net->max_mtu = dlci->mtu; mux_net = netdev_priv(net); mux_net->dlci = dlci; kref_init(&mux_net->ref); @@ -3352,13 +3710,14 @@ static struct tty_ldisc_ops tty_ldisc_packet = { static void gsm_modem_upd_via_data(struct gsm_dlci *dlci, u8 brk) { struct gsm_mux *gsm = dlci->gsm; + unsigned long flags; if (dlci->state != DLCI_OPEN || dlci->adaption != 2) return; - mutex_lock(&gsm->tx_mutex); + spin_lock_irqsave(&gsm->tx_lock, flags); gsm_dlci_modem_output(gsm, dlci, brk); - mutex_unlock(&gsm->tx_mutex); + spin_unlock_irqrestore(&gsm->tx_lock, flags); } /** |