From 266794eb71cfee65b38371954b9db2f6dbda207c Mon Sep 17 00:00:00 2001 From: Alan Cox Date: Mon, 8 Feb 2010 10:06:45 +0000 Subject: nozomi: Add tty_port usage The Nozomi tty handling is very broken on the open/close side (See http://bugzilla.kernel.org/show_bug.cgi?id=13024 for one example). In particular it marks the tty as closed on the first close() not on the last. Most of the logic is pretty solid except for the open/close path so switch to the tty_port helpers and let them do all the heavy lifting. This is also fixes all the POSIX behaviour violations in the open/close paths. Begin by adding the tty port usage Signed-off-by: Alan Cox Signed-off-by: Greg Kroah-Hartman --- drivers/char/nozomi.c | 115 +++++++++++++++++++++++++++++--------------------- 1 file changed, 68 insertions(+), 47 deletions(-) (limited to 'drivers/char/nozomi.c') diff --git a/drivers/char/nozomi.c b/drivers/char/nozomi.c index 2ad7d37afbd0..cd405bcf53a6 100644 --- a/drivers/char/nozomi.c +++ b/drivers/char/nozomi.c @@ -371,6 +371,8 @@ struct port { struct mutex tty_sem; wait_queue_head_t tty_wait; struct async_icount tty_icount; + + struct nozomi *dc; }; /* Private data one for each card in the system */ @@ -414,6 +416,8 @@ MODULE_DEVICE_TABLE(pci, nozomi_pci_tbl); static struct nozomi *ndevs[NOZOMI_MAX_CARDS]; static struct tty_driver *ntty_driver; +static const struct tty_port_operations noz_tty_port_ops; + /* * find card by tty_index */ @@ -1473,9 +1477,11 @@ static int __devinit nozomi_card_init(struct pci_dev *pdev, for (i = 0; i < MAX_PORT; i++) { struct device *tty_dev; - - mutex_init(&dc->port[i].tty_sem); - tty_port_init(&dc->port[i].port); + struct port *port = &dc->port[i]; + port->dc = dc; + mutex_init(&port->tty_sem); + tty_port_init(&port->port); + port->port.ops = &noz_tty_port_ops; tty_dev = tty_register_device(ntty_driver, dc->index_start + i, &pdev->dev); @@ -1600,67 +1606,74 @@ static void set_dtr(const struct tty_struct *tty, int dtr) * ---------------------------------------------------------------------------- */ -/* Called when the userspace process opens the tty, /dev/noz*. */ -static int ntty_open(struct tty_struct *tty, struct file *file) +static int ntty_install(struct tty_driver *driver, struct tty_struct *tty) { struct port *port = get_port_by_tty(tty); struct nozomi *dc = get_dc_by_tty(tty); - unsigned long flags; - + int ret; if (!port || !dc || dc->state != NOZOMI_STATE_READY) return -ENODEV; - - if (mutex_lock_interruptible(&port->tty_sem)) - return -ERESTARTSYS; - - port->port.count++; - dc->open_ttys++; - - /* Enable interrupt downlink for channel */ - if (port->port.count == 1) { - tty->driver_data = port; - tty_port_tty_set(&port->port, tty); - DBG1("open: %d", port->token_dl); - spin_lock_irqsave(&dc->spin_mutex, flags); - dc->last_ier = dc->last_ier | port->token_dl; - writew(dc->last_ier, dc->reg_ier); - spin_unlock_irqrestore(&dc->spin_mutex, flags); + ret = tty_init_termios(tty); + if (ret == 0) { + tty_driver_kref_get(driver); + driver->ttys[tty->index] = tty; } - mutex_unlock(&port->tty_sem); - return 0; + return ret; } -/* Called when the userspace process close the tty, /dev/noz*. Also - called immediately if ntty_open fails in which case tty->driver_data - will be NULL an we exit by the first return */ +static void ntty_cleanup(struct tty_struct *tty) +{ + tty->driver_data = NULL; +} -static void ntty_close(struct tty_struct *tty, struct file *file) +static int ntty_activate(struct tty_port *tport, struct tty_struct *tty) { - struct nozomi *dc = get_dc_by_tty(tty); - struct port *nport = tty->driver_data; - struct tty_port *port = &nport->port; + struct port *port = container_of(tport, struct port, port); + struct nozomi *dc = port->dc; unsigned long flags; - if (!dc || !nport) - return; + DBG1("open: %d", port->token_dl); + spin_lock_irqsave(&dc->spin_mutex, flags); + dc->last_ier = dc->last_ier | port->token_dl; + writew(dc->last_ier, dc->reg_ier); + dc->open_ttys++; + spin_unlock_irqrestore(&dc->spin_mutex, flags); + printk("noz: activated %d: %p\n", tty->index, tport); + return 0; +} - /* Users cannot interrupt a close */ - mutex_lock(&nport->tty_sem); +static int ntty_open(struct tty_struct *tty, struct file *filp) +{ + struct port *port = get_port_by_tty(tty); + return tty_port_open(&port->port, tty, filp); +} - WARN_ON(!port->count); +static void ntty_shutdown(struct tty_port *tport) +{ + struct port *port = container_of(tport, struct port, port); + struct nozomi *dc = port->dc; + unsigned long flags; + DBG1("close: %d", port->token_dl); + spin_lock_irqsave(&dc->spin_mutex, flags); + dc->last_ier &= ~(port->token_dl); + writew(dc->last_ier, dc->reg_ier); dc->open_ttys--; - port->count--; + spin_unlock_irqrestore(&dc->spin_mutex, flags); + printk("noz: shutdown %p\n", tport); +} - if (port->count == 0) { - DBG1("close: %d", nport->token_dl); - tty_port_tty_set(port, NULL); - spin_lock_irqsave(&dc->spin_mutex, flags); - dc->last_ier &= ~(nport->token_dl); - writew(dc->last_ier, dc->reg_ier); - spin_unlock_irqrestore(&dc->spin_mutex, flags); - } - mutex_unlock(&nport->tty_sem); +static void ntty_close(struct tty_struct *tty, struct file *filp) +{ + struct port *port = tty->driver_data; + if (port) + tty_port_close(&port->port, tty, filp); +} + +static void ntty_hangup(struct tty_struct *tty) +{ + struct port *port = tty->driver_data; + tty_port_hangup(&port->port); } /* @@ -1906,10 +1919,16 @@ exit_in_buffer: return rval; } +static const struct tty_port_operations noz_tty_port_ops = { + .activate = ntty_activate, + .shutdown = ntty_shutdown, +}; + static const struct tty_operations tty_ops = { .ioctl = ntty_ioctl, .open = ntty_open, .close = ntty_close, + .hangup = ntty_hangup, .write = ntty_write, .write_room = ntty_write_room, .unthrottle = ntty_unthrottle, @@ -1917,6 +1936,8 @@ static const struct tty_operations tty_ops = { .chars_in_buffer = ntty_chars_in_buffer, .tiocmget = ntty_tiocmget, .tiocmset = ntty_tiocmset, + .install = ntty_install, + .cleanup = ntty_cleanup, }; /* Module initialization */ -- cgit v1.2.3 From e8c65d143a9903cb553c0d80c819428c5b839a02 Mon Sep 17 00:00:00 2001 From: Alan Cox Date: Mon, 8 Feb 2010 10:07:04 +0000 Subject: nozomi: Fix mutex handling The original author didn't realise the kernel lock was a drop while sleep lock so did clever (and wrong) things to work around the non need to avoid deadlocks. Remove the cleverness and the comment (as we don't hold the BKL now anyway in those paths) Signed-off-by: Alan Cox Signed-off-by: Greg Kroah-Hartman --- drivers/char/nozomi.c | 34 ++++++++++++---------------------- 1 file changed, 12 insertions(+), 22 deletions(-) (limited to 'drivers/char/nozomi.c') diff --git a/drivers/char/nozomi.c b/drivers/char/nozomi.c index cd405bcf53a6..fac9157a0ec0 100644 --- a/drivers/char/nozomi.c +++ b/drivers/char/nozomi.c @@ -1693,15 +1693,7 @@ static int ntty_write(struct tty_struct *tty, const unsigned char *buffer, if (!dc || !port) return -ENODEV; - if (unlikely(!mutex_trylock(&port->tty_sem))) { - /* - * must test lock as tty layer wraps calls - * to this function with BKL - */ - dev_err(&dc->pdev->dev, "Would have deadlocked - " - "return EAGAIN\n"); - return -EAGAIN; - } + mutex_lock(&port->tty_sem); if (unlikely(!port->port.count)) { DBG1(" "); @@ -1741,25 +1733,23 @@ exit: * This method is called by the upper tty layer. * #according to sources N_TTY.c it expects a value >= 0 and * does not check for negative values. + * + * If the port is unplugged report lots of room and let the bits + * dribble away so we don't block anything. */ static int ntty_write_room(struct tty_struct *tty) { struct port *port = tty->driver_data; - int room = 0; + int room = 4096; const struct nozomi *dc = get_dc_by_tty(tty); - if (!dc || !port) - return 0; - if (!mutex_trylock(&port->tty_sem)) - return 0; - - if (!port->port.count) - goto exit; - - room = port->fifo_ul.size - kfifo_len(&port->fifo_ul); - -exit: - mutex_unlock(&port->tty_sem); + if (dc) { + mutex_lock(&port->tty_sem); + if (port->port.count) + room = port->fifo_ul.size - + kfifo_len(&port->fifo_ul); + mutex_unlock(&port->tty_sem); + } return room; } -- cgit v1.2.3 From b2a3dbc3ed401828c4de0f08d08d96d0f5ea5b0b Mon Sep 17 00:00:00 2001 From: Alan Cox Date: Mon, 8 Feb 2010 10:07:15 +0000 Subject: nozomi: Tidy up the PCI table Signed-off-by: Alan Cox Signed-off-by: Greg Kroah-Hartman --- drivers/char/nozomi.c | 6 +----- 1 file changed, 1 insertion(+), 5 deletions(-) (limited to 'drivers/char/nozomi.c') diff --git a/drivers/char/nozomi.c b/drivers/char/nozomi.c index fac9157a0ec0..584910ff725e 100644 --- a/drivers/char/nozomi.c +++ b/drivers/char/nozomi.c @@ -136,10 +136,6 @@ static int debug; #define RECEIVE_BUF_MAX 4 -/* Define all types of vendors and devices to support */ -#define VENDOR1 0x1931 /* Vendor Option */ -#define DEVICE1 0x000c /* HSDPA card */ - #define R_IIR 0x0000 /* Interrupt Identity Register */ #define R_FCR 0x0000 /* Flow Control Register */ #define R_IER 0x0004 /* Interrupt Enable Register */ @@ -407,7 +403,7 @@ struct buffer { /* Global variables */ static const struct pci_device_id nozomi_pci_tbl[] __devinitconst = { - {PCI_DEVICE(VENDOR1, DEVICE1)}, + {PCI_DEVICE(0x1931, 0x000c)}, /* Nozomi HSDPA */ {}, }; -- cgit v1.2.3 From 4165fe4ef7305609a96c7f248cefb9c414d0ede5 Mon Sep 17 00:00:00 2001 From: Alan Cox Date: Wed, 17 Feb 2010 13:07:13 +0000 Subject: tty: Fix up char drivers request_room usage We can't change them all but quite a few misuse it. Signed-off-by: Alan Cox Signed-off-by: Greg Kroah-Hartman --- drivers/char/nozomi.c | 2 -- drivers/char/serial167.c | 3 +-- drivers/char/specialix.c | 2 -- drivers/serial/icom.c | 1 - drivers/serial/ioc3_serial.c | 3 +-- 5 files changed, 2 insertions(+), 9 deletions(-) (limited to 'drivers/char/nozomi.c') diff --git a/drivers/char/nozomi.c b/drivers/char/nozomi.c index 584910ff725e..a3f32a15fde4 100644 --- a/drivers/char/nozomi.c +++ b/drivers/char/nozomi.c @@ -853,8 +853,6 @@ static int receive_data(enum port_type index, struct nozomi *dc) goto put; } - tty_buffer_request_room(tty, size); - while (size > 0) { read_mem32((u32 *) buf, addr + offset, RECEIVE_BUF_MAX); diff --git a/drivers/char/serial167.c b/drivers/char/serial167.c index 452370af95de..986aa606a6b6 100644 --- a/drivers/char/serial167.c +++ b/drivers/char/serial167.c @@ -658,8 +658,7 @@ static irqreturn_t cd2401_rx_interrupt(int irq, void *dev_id) info->mon.char_max = char_count; info->mon.char_last = char_count; #endif - len = tty_buffer_request_room(tty, char_count); - while (len--) { + while (char_count--) { data = base_addr[CyRDR]; tty_insert_flip_char(tty, data, TTY_NORMAL); #ifdef CYCLOM_16Y_HACK diff --git a/drivers/char/specialix.c b/drivers/char/specialix.c index 268e17f9ec3f..07ac14d949ce 100644 --- a/drivers/char/specialix.c +++ b/drivers/char/specialix.c @@ -646,8 +646,6 @@ static void sx_receive(struct specialix_board *bp) dprintk(SX_DEBUG_RX, "port: %p: count: %d\n", port, count); port->hits[count > 8 ? 9 : count]++; - tty_buffer_request_room(tty, count); - while (count--) tty_insert_flip_char(tty, sx_in(bp, CD186x_RDR), TTY_NORMAL); tty_flip_buffer_push(tty); diff --git a/drivers/serial/icom.c b/drivers/serial/icom.c index 6e715b78d7a6..53a468227056 100644 --- a/drivers/serial/icom.c +++ b/drivers/serial/icom.c @@ -751,7 +751,6 @@ static void recv_interrupt(u16 port_int_reg, struct icom_port *icom_port) trace(icom_port, "FID_STATUS", status); count = cpu_to_le16(icom_port->statStg->rcv[rcv_buff].leLength); - count = tty_buffer_request_room(tty, count); trace(icom_port, "RCV_COUNT", count); trace(icom_port, "REAL_COUNT", count); diff --git a/drivers/serial/ioc3_serial.c b/drivers/serial/ioc3_serial.c index 85dc0410ac1a..23ba6b40b3ac 100644 --- a/drivers/serial/ioc3_serial.c +++ b/drivers/serial/ioc3_serial.c @@ -1411,8 +1411,7 @@ static int receive_chars(struct uart_port *the_port) read_count = do_read(the_port, ch, MAX_CHARS); if (read_count > 0) { flip = 1; - read_room = tty_buffer_request_room(tty, read_count); - tty_insert_flip_string(tty, ch, read_room); + read_room = tty_insert_flip_string(tty, ch, read_count); the_port->icount.rx += read_count; } spin_unlock_irqrestore(&the_port->lock, pflags); -- cgit v1.2.3