Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757316AbZKRObu (ORCPT ); Wed, 18 Nov 2009 09:31:50 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1757263AbZKRObt (ORCPT ); Wed, 18 Nov 2009 09:31:49 -0500 Received: from earthlight.etchedpixels.co.uk ([81.2.110.250]:40595 "EHLO bob.linux.org.uk" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1757166AbZKRObr (ORCPT ); Wed, 18 Nov 2009 09:31:47 -0500 From: Alan Cox Subject: [PATCH 04/12] mxser: Use the new locking rules to fix setserial properly To: greg@kroah.com, linux-kernel@vger.kernel.org Date: Wed, 18 Nov 2009 14:15:23 +0000 Message-ID: <20091118141516.3346.1769.stgit@localhost.localdomain> In-Reply-To: <20091118141354.3346.16910.stgit@localhost.localdomain> References: <20091118141354.3346.16910.stgit@localhost.localdomain> User-Agent: StGIT/0.14.3 MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 12566 Lines: 387 Propogate the init/shutdown mutex through the setserial logic. Use the proper locks for the various bits still using the BKL. Kill the BKL in this driver. Signed-off-by: Alan Cox --- drivers/char/mxser.c | 145 +++++++++++++++++++++++++++----------------------- 1 files changed, 78 insertions(+), 67 deletions(-) diff --git a/drivers/char/mxser.c b/drivers/char/mxser.c index 9dac516..4c803c7 100644 --- a/drivers/char/mxser.c +++ b/drivers/char/mxser.c @@ -23,7 +23,6 @@ #include #include #include -#include #include #include #include @@ -1229,6 +1228,7 @@ static int mxser_set_serial_info(struct tty_struct *tty, struct serial_struct __user *new_info) { struct mxser_port *info = tty->driver_data; + struct tty_port *port = &info->port; struct serial_struct new_serial; speed_t baud; unsigned long sl_flags; @@ -1244,7 +1244,7 @@ static int mxser_set_serial_info(struct tty_struct *tty, new_serial.port != info->ioaddr) return -EINVAL; - flags = info->port.flags & ASYNC_SPD_MASK; + flags = port->flags & ASYNC_SPD_MASK; if (!capable(CAP_SYS_ADMIN)) { if ((new_serial.baud_base != info->baud_base) || @@ -1258,16 +1258,17 @@ static int mxser_set_serial_info(struct tty_struct *tty, * OK, past this point, all the error checking has been done. * At this point, we start making changes..... */ - info->port.flags = ((info->port.flags & ~ASYNC_FLAGS) | + port->flags = ((port->flags & ~ASYNC_FLAGS) | (new_serial.flags & ASYNC_FLAGS)); - info->port.close_delay = new_serial.close_delay * HZ / 100; - info->port.closing_wait = new_serial.closing_wait * HZ / 100; - tty->low_latency = (info->port.flags & ASYNC_LOW_LATENCY) - ? 1 : 0; - if ((info->port.flags & ASYNC_SPD_MASK) == ASYNC_SPD_CUST && + port->close_delay = new_serial.close_delay * HZ / 100; + port->closing_wait = new_serial.closing_wait * HZ / 100; + tty->low_latency = (port->flags & ASYNC_LOW_LATENCY) ? 1 : 0; + if ((port->flags & ASYNC_SPD_MASK) == ASYNC_SPD_CUST && (new_serial.baud_base != info->baud_base || new_serial.custom_divisor != info->custom_divisor)) { + if (new_serial.custom_divisor == 0) + return -EINVAL; baud = new_serial.baud_base / new_serial.custom_divisor; tty_encode_baud_rate(tty, baud, baud); } @@ -1277,18 +1278,16 @@ static int mxser_set_serial_info(struct tty_struct *tty, process_txrx_fifo(info); - if (info->port.flags & ASYNC_INITIALIZED) { - if (flags != (info->port.flags & ASYNC_SPD_MASK)) { + if (test_bit(ASYNCB_INITIALIZED, &port->flags)) { + if (flags != (port->flags & ASYNC_SPD_MASK)) { spin_lock_irqsave(&info->slock, sl_flags); mxser_change_speed(tty, NULL); spin_unlock_irqrestore(&info->slock, sl_flags); } } else { - mutex_lock(&info->port.mutex); - retval = mxser_activate(&info->port, tty); + retval = mxser_activate(port, tty); if (retval == 0) - set_bit(ASYNCB_INITIALIZED, &info->port.flags); - mutex_unlock(&info->port.mutex); + set_bit(ASYNCB_INITIALIZED, &port->flags); } return retval; } @@ -1478,7 +1477,8 @@ static int __init mxser_read_register(int port, unsigned short *regs) static int mxser_ioctl_special(unsigned int cmd, void __user *argp) { - struct mxser_port *port; + struct mxser_port *ip; + struct tty_port *port; struct tty_struct *tty; int result, status; unsigned int i, j; @@ -1494,38 +1494,39 @@ static int mxser_ioctl_special(unsigned int cmd, void __user *argp) case MOXA_CHKPORTENABLE: result = 0; - lock_kernel(); for (i = 0; i < MXSER_BOARDS; i++) for (j = 0; j < MXSER_PORTS_PER_BOARD; j++) if (mxser_boards[i].ports[j].ioaddr) result |= (1 << i); - unlock_kernel(); return put_user(result, (unsigned long __user *)argp); case MOXA_GETDATACOUNT: - lock_kernel(); + /* The receive side is locked by port->slock but it isn't + clear that an exact snapshot is worth copying here */ if (copy_to_user(argp, &mxvar_log, sizeof(mxvar_log))) ret = -EFAULT; - unlock_kernel(); return ret; case MOXA_GETMSTATUS: { struct mxser_mstatus ms, __user *msu = argp; - lock_kernel(); for (i = 0; i < MXSER_BOARDS; i++) for (j = 0; j < MXSER_PORTS_PER_BOARD; j++) { - port = &mxser_boards[i].ports[j]; + ip = &mxser_boards[i].ports[j]; + port = &ip->port; memset(&ms, 0, sizeof(ms)); - if (!port->ioaddr) + mutex_lock(&port->mutex); + if (!ip->ioaddr) goto copy; - tty = tty_port_tty_get(&port->port); + tty = tty_port_tty_get(port); if (!tty || !tty->termios) - ms.cflag = port->normal_termios.c_cflag; + ms.cflag = ip->normal_termios.c_cflag; else ms.cflag = tty->termios->c_cflag; tty_kref_put(tty); - status = inb(port->ioaddr + UART_MSR); + spin_lock_irq(&ip->slock); + status = inb(ip->ioaddr + UART_MSR); + spin_unlock_irq(&ip->slock); if (status & UART_MSR_DCD) ms.dcd = 1; if (status & UART_MSR_DSR) @@ -1533,13 +1534,11 @@ static int mxser_ioctl_special(unsigned int cmd, void __user *argp) if (status & UART_MSR_CTS) ms.cts = 1; copy: - if (copy_to_user(msu, &ms, sizeof(ms))) { - unlock_kernel(); + mutex_unlock(&port->mutex); + if (copy_to_user(msu, &ms, sizeof(ms))) return -EFAULT; - } msu++; } - unlock_kernel(); return 0; } case MOXA_ASPP_MON_EXT: { @@ -1551,41 +1550,48 @@ static int mxser_ioctl_special(unsigned int cmd, void __user *argp) if (!me) return -ENOMEM; - lock_kernel(); for (i = 0, p = 0; i < MXSER_BOARDS; i++) { for (j = 0; j < MXSER_PORTS_PER_BOARD; j++, p++) { if (p >= ARRAY_SIZE(me->rx_cnt)) { i = MXSER_BOARDS; break; } - port = &mxser_boards[i].ports[j]; - if (!port->ioaddr) + ip = &mxser_boards[i].ports[j]; + port = &ip->port; + + mutex_lock(&port->mutex); + if (!ip->ioaddr) { + mutex_unlock(&port->mutex); continue; + } - status = mxser_get_msr(port->ioaddr, 0, p); + spin_lock_irq(&ip->slock); + status = mxser_get_msr(ip->ioaddr, 0, p); if (status & UART_MSR_TERI) - port->icount.rng++; + ip->icount.rng++; if (status & UART_MSR_DDSR) - port->icount.dsr++; + ip->icount.dsr++; if (status & UART_MSR_DDCD) - port->icount.dcd++; + ip->icount.dcd++; if (status & UART_MSR_DCTS) - port->icount.cts++; + ip->icount.cts++; - port->mon_data.modem_status = status; - me->rx_cnt[p] = port->mon_data.rxcnt; - me->tx_cnt[p] = port->mon_data.txcnt; - me->up_rxcnt[p] = port->mon_data.up_rxcnt; - me->up_txcnt[p] = port->mon_data.up_txcnt; + ip->mon_data.modem_status = status; + me->rx_cnt[p] = ip->mon_data.rxcnt; + me->tx_cnt[p] = ip->mon_data.txcnt; + me->up_rxcnt[p] = ip->mon_data.up_rxcnt; + me->up_txcnt[p] = ip->mon_data.up_txcnt; me->modem_status[p] = - port->mon_data.modem_status; - tty = tty_port_tty_get(&port->port); + ip->mon_data.modem_status; + spin_unlock_irq(&ip->slock); + + tty = tty_port_tty_get(&ip->port); if (!tty || !tty->termios) { - cflag = port->normal_termios.c_cflag; - iflag = port->normal_termios.c_iflag; - me->baudrate[p] = tty_termios_baud_rate(&port->normal_termios); + cflag = ip->normal_termios.c_cflag; + iflag = ip->normal_termios.c_iflag; + me->baudrate[p] = tty_termios_baud_rate(&ip->normal_termios); } else { cflag = tty->termios->c_cflag; iflag = tty->termios->c_iflag; @@ -1604,16 +1610,15 @@ static int mxser_ioctl_special(unsigned int cmd, void __user *argp) if (iflag & (IXON | IXOFF)) me->flowctrl[p] |= 0x0C; - if (port->type == PORT_16550A) + if (ip->type == PORT_16550A) me->fifo[p] = 1; - opmode = inb(port->opmode_ioaddr) >> - ((p % 4) * 2); + opmode = inb(ip->opmode_ioaddr)>>((p % 4) * 2); opmode &= OP_MODE_MASK; me->iftype[p] = opmode; + mutex_unlock(&port->mutex); } } - unlock_kernel(); if (copy_to_user(argp, me, sizeof(*me))) ret = -EFAULT; kfree(me); @@ -1650,6 +1655,7 @@ static int mxser_ioctl(struct tty_struct *tty, struct file *file, unsigned int cmd, unsigned long arg) { struct mxser_port *info = tty->driver_data; + struct tty_port *port = &info->port; struct async_icount cnow; unsigned long flags; void __user *argp = (void __user *)arg; @@ -1674,20 +1680,20 @@ static int mxser_ioctl(struct tty_struct *tty, struct file *file, opmode != RS422_MODE && opmode != RS485_4WIRE_MODE) return -EFAULT; - lock_kernel(); mask = ModeMask[p]; shiftbit = p * 2; + spin_lock_irq(&info->slock); val = inb(info->opmode_ioaddr); val &= mask; val |= (opmode << shiftbit); outb(val, info->opmode_ioaddr); - unlock_kernel(); + spin_unlock_irq(&info->slock); } else { - lock_kernel(); shiftbit = p * 2; + spin_lock_irq(&info->slock); opmode = inb(info->opmode_ioaddr) >> shiftbit; + spin_unlock_irq(&info->slock); opmode &= OP_MODE_MASK; - unlock_kernel(); if (put_user(opmode, (int __user *)argp)) return -EFAULT; } @@ -1700,14 +1706,14 @@ static int mxser_ioctl(struct tty_struct *tty, struct file *file, switch (cmd) { case TIOCGSERIAL: - lock_kernel(); + mutex_lock(&port->mutex); retval = mxser_get_serial_info(tty, argp); - unlock_kernel(); + mutex_unlock(&port->mutex); return retval; case TIOCSSERIAL: - lock_kernel(); + mutex_lock(&port->mutex); retval = mxser_set_serial_info(tty, argp); - unlock_kernel(); + mutex_unlock(&port->mutex); return retval; case TIOCSERGETLSR: /* Get line status register */ return mxser_get_lsr_info(info, argp); @@ -1753,31 +1759,33 @@ static int mxser_ioctl(struct tty_struct *tty, struct file *file, case MOXA_HighSpeedOn: return put_user(info->baud_base != 115200 ? 1 : 0, (int __user *)argp); case MOXA_SDS_RSTICOUNTER: - lock_kernel(); + spin_lock_irq(&info->slock); info->mon_data.rxcnt = 0; info->mon_data.txcnt = 0; - unlock_kernel(); + spin_unlock_irq(&info->slock); return 0; case MOXA_ASPP_OQUEUE:{ int len, lsr; - lock_kernel(); len = mxser_chars_in_buffer(tty); + spin_lock(&info->slock); lsr = inb(info->ioaddr + UART_LSR) & UART_LSR_THRE; + spin_unlock_irq(&info->slock); len += (lsr ? 0 : 1); - unlock_kernel(); return put_user(len, (int __user *)argp); } case MOXA_ASPP_MON: { int mcr, status; - lock_kernel(); + spin_lock(&info->slock); status = mxser_get_msr(info->ioaddr, 1, tty->index); mxser_check_modem_status(tty, info, status); mcr = inb(info->ioaddr + UART_MCR); + spin_unlock(&info->slock); + if (mcr & MOXA_MUST_MCR_XON_FLAG) info->mon_data.hold_reason &= ~NPPI_NOTIFY_XOFFHOLD; else @@ -1792,7 +1800,7 @@ static int mxser_ioctl(struct tty_struct *tty, struct file *file, info->mon_data.hold_reason |= NPPI_NOTIFY_CTSHOLD; else info->mon_data.hold_reason &= ~NPPI_NOTIFY_CTSHOLD; - unlock_kernel(); + if (copy_to_user(argp, &info->mon_data, sizeof(struct mxser_mon))) return -EFAULT; @@ -1951,6 +1959,7 @@ static void mxser_wait_until_sent(struct tty_struct *tty, int timeout) { struct mxser_port *info = tty->driver_data; unsigned long orig_jiffies, char_time; + unsigned long flags; int lsr; if (info->type == PORT_UNKNOWN) @@ -1990,19 +1999,21 @@ static void mxser_wait_until_sent(struct tty_struct *tty, int timeout) timeout, char_time); printk("jiff=%lu...", jiffies); #endif - lock_kernel(); + spin_lock_irqsave(&info->slock, flags); while (!((lsr = inb(info->ioaddr + UART_LSR)) & UART_LSR_TEMT)) { #ifdef SERIAL_DEBUG_RS_WAIT_UNTIL_SENT printk("lsr = %d (jiff=%lu)...", lsr, jiffies); #endif + spin_unlock_irqrestore(&info->slock, flags); schedule_timeout_interruptible(char_time); if (signal_pending(current)) break; if (timeout && time_after(jiffies, orig_jiffies + timeout)) break; + spin_lock_irqsave(&info->slock, flags); } + spin_unlock_irqrestore(&info->slock, flags); set_current_state(TASK_RUNNING); - unlock_kernel(); #ifdef SERIAL_DEBUG_RS_WAIT_UNTIL_SENT printk("lsr = %d (jiff=%lu)...done\n", lsr, jiffies); -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/