admin/linux
1
0
Fork 0
mirror of https://github.com/torvalds/linux.git synced 2025-12-07 20:06:24 +00:00
Code Issues Packages Projects Releases Wiki Activity

mxser: use guard()s

Browse Source 
Having all the new guards, use them in the mxser code. This improves
readability, makes error handling easier, and marks locked portions of
code explicit.

Signed-off-by: "Jiri Slaby (SUSE)" <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20250814072456.182853-8-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Jiri Slaby (SUSE)
2025-08-14 09:24:47 +02:00
committed by Greg Kroah-Hartman
parent 81600e92a0
commit 793b450112
1 changed files with 74 additions and 123 deletions
Download Patch File Download Diff File Expand all files Collapse all files

197
drivers/tty/mxser.c
View File

@@ -442,11 +442,8 @@ static void __mxser_start_tx(struct mxser_port *info)
static void mxser_start_tx(struct mxser_port *info)
{
unsigned long flags;
spin_lock_irqsave(&info->slock, flags);
guard(spinlock_irqsave)(&info->slock);
__mxser_start_tx(info);
spin_unlock_irqrestore(&info->slock, flags);
}
static void __mxser_stop_tx(struct mxser_port *info)
@@ -465,17 +462,15 @@ static bool mxser_carrier_raised(struct tty_port *port)
static void mxser_dtr_rts(struct tty_port *port, bool active)
{
struct mxser_port *mp = container_of(port, struct mxser_port, port);
unsigned long flags;
u8 mcr;
spin_lock_irqsave(&mp->slock, flags);
guard(spinlock_irqsave)(&mp->slock);
mcr = inb(mp->ioaddr + UART_MCR);
if (active)
mcr |= UART_MCR_DTR | UART_MCR_RTS;
else
mcr &= ~(UART_MCR_DTR | UART_MCR_RTS);
outb(mcr, mp->ioaddr + UART_MCR);
spin_unlock_irqrestore(&mp->slock, flags);
}
static int mxser_set_baud(struct tty_struct *tty, speed_t newspd)
@@ -828,32 +823,28 @@ static void mxser_stop_rx(struct mxser_port *info)
static void mxser_shutdown_port(struct tty_port *port)
{
struct mxser_port *info = container_of(port, struct mxser_port, port);
unsigned long flags;
spin_lock_irqsave(&info->slock, flags);
scoped_guard(spinlock_irqsave, &info->slock) {
mxser_stop_rx(info);
mxser_stop_rx(info);
/*
* clear delta_msr_wait queue to avoid mem leaks: we may free the irq
* here so the queue might never be waken up
*/
wake_up_interruptible(&info->port.delta_msr_wait);
/*
* clear delta_msr_wait queue to avoid mem leaks: we may free the irq
* here so the queue might never be waken up
*/
wake_up_interruptible(&info->port.delta_msr_wait);
info->IER = 0;
outb(0x00, info->ioaddr + UART_IER);
info->IER = 0;
outb(0x00, info->ioaddr + UART_IER);
/* clear Rx/Tx FIFO's */
mxser_disable_and_clear_FIFO(info);
/* clear Rx/Tx FIFO's */
mxser_disable_and_clear_FIFO(info);
/* read data port to reset things */
(void)inb(info->ioaddr + UART_RX);
/* read data port to reset things */
(void) inb(info->ioaddr + UART_RX);
if (info->board->must_hwid)
mxser_must_no_sw_flow_control(info->ioaddr);
spin_unlock_irqrestore(&info->slock, flags);
if (info->board->must_hwid)
mxser_must_no_sw_flow_control(info->ioaddr);
}
/* make sure ISR is not running while we free the buffer */
synchronize_irq(info->board->irq);
@@ -880,15 +871,13 @@ static int mxser_open(struct tty_struct *tty, struct file *filp)
static void mxser_flush_buffer(struct tty_struct *tty)
{
struct mxser_port *info = tty->driver_data;
unsigned long flags;
spin_lock_irqsave(&info->slock, flags);
kfifo_reset(&info->port.xmit_fifo);
scoped_guard(spinlock_irqsave, &info->slock) {
kfifo_reset(&info->port.xmit_fifo);
outb(info->FCR | UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT,
info->ioaddr + UART_FCR);
spin_unlock_irqrestore(&info->slock, flags);
outb(info->FCR | UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT,
info->ioaddr + UART_FCR);
}
tty_wakeup(tty);
}
@@ -901,14 +890,13 @@ static void mxser_close(struct tty_struct *tty, struct file *filp)
static ssize_t mxser_write(struct tty_struct *tty, const u8 *buf, size_t count)
{
struct mxser_port *info = tty->driver_data;
unsigned long flags;
size_t written;
bool is_empty;
spin_lock_irqsave(&info->slock, flags);
written = kfifo_in(&info->port.xmit_fifo, buf, count);
is_empty = kfifo_is_empty(&info->port.xmit_fifo);
spin_unlock_irqrestore(&info->slock, flags);
scoped_guard(spinlock_irqsave, &info->slock) {
written = kfifo_in(&info->port.xmit_fifo, buf, count);
is_empty = kfifo_is_empty(&info->port.xmit_fifo);
}
if (!is_empty && !tty->flow.stopped)
if (!tty->hw_stopped || mxser_16550A_or_MUST(info))
@@ -920,14 +908,9 @@ static ssize_t mxser_write(struct tty_struct *tty, const u8 *buf, size_t count)
static int mxser_put_char(struct tty_struct *tty, u8 ch)
{
struct mxser_port *info = tty->driver_data;
unsigned long flags;
int ret;
spin_lock_irqsave(&info->slock, flags);
ret = kfifo_put(&info->port.xmit_fifo, ch);
spin_unlock_irqrestore(&info->slock, flags);
return ret;
guard(spinlock_irqsave)(&info->slock);
return kfifo_put(&info->port.xmit_fifo, ch);
}
@@ -968,7 +951,7 @@ static int mxser_get_serial_info(struct tty_struct *tty,
struct tty_port *port = &info->port;
unsigned int closing_wait, close_delay;
mutex_lock(&port->mutex);
guard(mutex)(&port->mutex);
close_delay = jiffies_to_msecs(info->port.close_delay) / 10;
closing_wait = info->port.closing_wait;
@@ -984,7 +967,7 @@ static int mxser_get_serial_info(struct tty_struct *tty,
ss->close_delay = close_delay;
ss->closing_wait = closing_wait;
ss->custom_divisor = MXSER_CUSTOM_DIVISOR;
mutex_unlock(&port->mutex);
return 0;
}
@@ -994,20 +977,15 @@ static int mxser_set_serial_info(struct tty_struct *tty,
struct mxser_port *info = tty->driver_data;
struct tty_port *port = &info->port;
speed_t baud;
unsigned long sl_flags;
unsigned int old_speed, close_delay, closing_wait;
int retval = 0;
if (tty_io_error(tty))
return -EIO;
mutex_lock(&port->mutex);
guard(mutex)(&port->mutex);
if (ss->irq != info->board->irq ||
ss->port != info->ioaddr) {
mutex_unlock(&port->mutex);
if (ss->irq != info->board->irq || ss->port != info->ioaddr)
return -EINVAL;
}
old_speed = port->flags & ASYNC_SPD_MASK;
@@ -1020,10 +998,9 @@ static int mxser_set_serial_info(struct tty_struct *tty,
if ((ss->baud_base != MXSER_BAUD_BASE) ||
(close_delay != port->close_delay) ||
(closing_wait != port->closing_wait) ||
((ss->flags & ~ASYNC_USR_MASK) != (port->flags & ~ASYNC_USR_MASK))) {
mutex_unlock(&port->mutex);
((ss->flags & ~ASYNC_USR_MASK) != (port->flags & ~ASYNC_USR_MASK)))
return -EPERM;
}
port->flags = (port->flags & ~ASYNC_USR_MASK) |
(ss->flags & ASYNC_USR_MASK);
} else {
@@ -1039,10 +1016,9 @@ static int mxser_set_serial_info(struct tty_struct *tty,
(ss->baud_base != MXSER_BAUD_BASE ||
ss->custom_divisor !=
MXSER_CUSTOM_DIVISOR)) {
if (ss->custom_divisor == 0) {
mutex_unlock(&port->mutex);
if (ss->custom_divisor == 0)
return -EINVAL;
}
baud = ss->baud_base / ss->custom_divisor;
tty_encode_baud_rate(tty, baud, baud);
}
@@ -1054,16 +1030,17 @@ static int mxser_set_serial_info(struct tty_struct *tty,
if (tty_port_initialized(port)) {
if (old_speed != (port->flags & ASYNC_SPD_MASK)) {
spin_lock_irqsave(&info->slock, sl_flags);
guard(spinlock_irqsave)(&info->slock);
mxser_change_speed(tty, NULL);
spin_unlock_irqrestore(&info->slock, sl_flags);
}
} else {
retval = mxser_activate(port, tty);
if (retval == 0)
tty_port_set_initialized(port, true);
return 0;
}
mutex_unlock(&port->mutex);
int retval = mxser_activate(port, tty);
if (retval == 0)
tty_port_set_initialized(port, true);
return retval;
}
@@ -1080,13 +1057,11 @@ static int mxser_set_serial_info(struct tty_struct *tty,
static int mxser_get_lsr_info(struct mxser_port *info,
unsigned int __user *value)
{
unsigned char status;
unsigned int result;
unsigned long flags;
u8 status;
spin_lock_irqsave(&info->slock, flags);
status = inb(info->ioaddr + UART_LSR);
spin_unlock_irqrestore(&info->slock, flags);
scoped_guard(spinlock_irqsave, &info->slock)
status = inb(info->ioaddr + UART_LSR);
result = ((status & UART_LSR_TEMT) ? TIOCSER_TEMT : 0);
return put_user(result, value);
}
@@ -1095,16 +1070,15 @@ static int mxser_tiocmget(struct tty_struct *tty)
{
struct mxser_port *info = tty->driver_data;
unsigned char control;
unsigned long flags;
u8 msr;
if (tty_io_error(tty))
return -EIO;
spin_lock_irqsave(&info->slock, flags);
control = info->MCR;
msr = mxser_check_modem_status(tty, info);
spin_unlock_irqrestore(&info->slock, flags);
scoped_guard(spinlock_irqsave, &info->slock) {
control = info->MCR;
msr = mxser_check_modem_status(tty, info);
}
return ((control & UART_MCR_RTS) ? TIOCM_RTS : 0) |
((control & UART_MCR_DTR) ? TIOCM_DTR : 0) |
@@ -1118,12 +1092,11 @@ static int mxser_tiocmset(struct tty_struct *tty,
unsigned int set, unsigned int clear)
{
struct mxser_port *info = tty->driver_data;
unsigned long flags;
if (tty_io_error(tty))
return -EIO;
spin_lock_irqsave(&info->slock, flags);
guard(spinlock_irqsave)(&info->slock);
if (set & TIOCM_RTS)
info->MCR |= UART_MCR_RTS;
@@ -1136,7 +1109,7 @@ static int mxser_tiocmset(struct tty_struct *tty,
info->MCR &= ~UART_MCR_DTR;
outb(info->MCR, info->ioaddr + UART_MCR);
spin_unlock_irqrestore(&info->slock, flags);
return 0;
}
@@ -1144,12 +1117,11 @@ static int mxser_cflags_changed(struct mxser_port *info, unsigned long arg,
struct async_icount *cprev)
{
struct async_icount cnow;
unsigned long flags;
int ret;
spin_lock_irqsave(&info->slock, flags);
cnow = info->icount; /* atomic copy */
spin_unlock_irqrestore(&info->slock, flags);
/* atomic copy */
scoped_guard(spinlock_irqsave, &info->slock)
cnow = info->icount;
ret = ((arg & TIOCM_RNG) && (cnow.rng != cprev->rng)) ||
((arg & TIOCM_DSR) && (cnow.dsr != cprev->dsr)) ||
@@ -1179,19 +1151,17 @@ static int mxser_ioctl_op_mode(struct mxser_port *port, int index, bool set,
if (opmode & ~OP_MODE_MASK)
return -EINVAL;
spin_lock_irq(&port->slock);
guard(spinlock_irq)(&port->slock);
val = inb(port->opmode_ioaddr);
val &= ~(OP_MODE_MASK << shiftbit);
val |= (opmode << shiftbit);
outb(val, port->opmode_ioaddr);
spin_unlock_irq(&port->slock);
return 0;
}
spin_lock_irq(&port->slock);
opmode = inb(port->opmode_ioaddr) >> shiftbit;
spin_unlock_irq(&port->slock);
scoped_guard(spinlock_irq, &port->slock)
opmode = inb(port->opmode_ioaddr) >> shiftbit;
return put_user(opmode & OP_MODE_MASK, u_opmode);
}
@@ -1201,7 +1171,6 @@ static int mxser_ioctl(struct tty_struct *tty,
{
struct mxser_port *info = tty->driver_data;
struct async_icount cnow;
unsigned long flags;
void __user *argp = (void __user *)arg;
if (cmd == MOXA_SET_OP_MODE || cmd == MOXA_GET_OP_MODE)
@@ -1221,9 +1190,9 @@ static int mxser_ioctl(struct tty_struct *tty,
* Caller should use TIOCGICOUNT to see which one it was
*/
case TIOCMIWAIT:
spin_lock_irqsave(&info->slock, flags);
cnow = info->icount; /* note the counters on entry */
spin_unlock_irqrestore(&info->slock, flags);
/* note the counters on entry */
scoped_guard(spinlock_irqsave, &info->slock)
cnow = info->icount;
return wait_event_interruptible(info->port.delta_msr_wait,
mxser_cflags_changed(info, arg, &cnow));
@@ -1246,11 +1215,9 @@ static int mxser_get_icount(struct tty_struct *tty,
{
struct mxser_port *info = tty->driver_data;
struct async_icount cnow;
unsigned long flags;
spin_lock_irqsave(&info->slock, flags);
cnow = info->icount;
spin_unlock_irqrestore(&info->slock, flags);
scoped_guard(spinlock_irqsave, &info->slock)
cnow = info->icount;
icount->frame = cnow.frame;
icount->brk = cnow.brk;
@@ -1328,34 +1295,28 @@ static void mxser_unthrottle(struct tty_struct *tty)
static void mxser_stop(struct tty_struct *tty)
{
struct mxser_port *info = tty->driver_data;
unsigned long flags;
spin_lock_irqsave(&info->slock, flags);
guard(spinlock_irqsave)(&info->slock);
if (info->IER & UART_IER_THRI)
__mxser_stop_tx(info);
spin_unlock_irqrestore(&info->slock, flags);
}
static void mxser_start(struct tty_struct *tty)
{
struct mxser_port *info = tty->driver_data;
unsigned long flags;
spin_lock_irqsave(&info->slock, flags);
guard(spinlock_irqsave)(&info->slock);
if (!kfifo_is_empty(&info->port.xmit_fifo))
__mxser_start_tx(info);
spin_unlock_irqrestore(&info->slock, flags);
}
static void mxser_set_termios(struct tty_struct *tty,
const struct ktermios *old_termios)
{
struct mxser_port *info = tty->driver_data;
unsigned long flags;
spin_lock_irqsave(&info->slock, flags);
mxser_change_speed(tty, old_termios);
spin_unlock_irqrestore(&info->slock, flags);
scoped_guard(spinlock_irqsave, &info->slock)
mxser_change_speed(tty, old_termios);
if ((old_termios->c_cflag & CRTSCTS) && !C_CRTSCTS(tty)) {
tty->hw_stopped = false;
@@ -1367,9 +1328,8 @@ static void mxser_set_termios(struct tty_struct *tty,
tty->flow.stopped = 0;
if (info->board->must_hwid) {
spin_lock_irqsave(&info->slock, flags);
guard(spinlock_irqsave)(&info->slock);
mxser_must_set_rx_sw_flow_control(info->ioaddr, false);
spin_unlock_irqrestore(&info->slock, flags);
}
mxser_start(tty);
@@ -1378,14 +1338,8 @@ static void mxser_set_termios(struct tty_struct *tty,
static bool mxser_tx_empty(struct mxser_port *info)
{
unsigned long flags;
u8 lsr;
spin_lock_irqsave(&info->slock, flags);
lsr = inb(info->ioaddr + UART_LSR);
spin_unlock_irqrestore(&info->slock, flags);
return !(lsr & UART_LSR_TEMT);
guard(spinlock_irqsave)(&info->slock);
return !(inb(info->ioaddr + UART_LSR) & UART_LSR_TEMT);
}
/*
@@ -1459,17 +1413,15 @@ static void mxser_hangup(struct tty_struct *tty)
static int mxser_rs_break(struct tty_struct *tty, int break_state)
{
struct mxser_port *info = tty->driver_data;
unsigned long flags;
u8 lcr;
spin_lock_irqsave(&info->slock, flags);
guard(spinlock_irqsave)(&info->slock);
lcr = inb(info->ioaddr + UART_LCR);
if (break_state == -1)
lcr |= UART_LCR_SBC;
else
lcr &= ~UART_LCR_SBC;
outb(lcr, info->ioaddr + UART_LCR);
spin_unlock_irqrestore(&info->slock, flags);
return 0;
}
@@ -1672,12 +1624,11 @@ static irqreturn_t mxser_interrupt(int irq, void *dev_id)
port = &brd->ports[i];
int_cnt = 0;
spin_lock(&port->slock);
guard(spinlock)(&port->slock);
do {
if (mxser_port_isr(port))
break;
} while (int_cnt++ < MXSER_ISR_PASS_LIMIT);
spin_unlock(&port->slock);
}
}