diff options
author | David S. Miller <davem@davemloft.net> | 2007-07-18 02:34:05 -0700 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@suse.de> | 2007-08-09 14:27:26 -0700 |
commit | 64be2d2b176e1e5c2fa10e7df7fdd87480c08971 (patch) | |
tree | de2a1c52f062d13fa155f63068ca764c21e222b9 | |
parent | 3ee0edac473755afa68715acd1d0e569044bae39 (diff) | |
download | lwn-64be2d2b176e1e5c2fa10e7df7fdd87480c08971.tar.gz lwn-64be2d2b176e1e5c2fa10e7df7fdd87480c08971.zip |
Fix console write locking in sparc drivers.
Mirror the logic in 8250 for proper console write locking
when SYSRQ is triggered or an OOPS is in progress.
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
-rw-r--r-- | drivers/serial/sunhv.c | 30 | ||||
-rw-r--r-- | drivers/serial/sunsab.c | 19 | ||||
-rw-r--r-- | drivers/serial/sunsu.c | 14 | ||||
-rw-r--r-- | drivers/serial/sunzilog.c | 17 |
4 files changed, 68 insertions, 12 deletions
diff --git a/drivers/serial/sunhv.c b/drivers/serial/sunhv.c index 96557e6dba60..17bcca53d6a1 100644 --- a/drivers/serial/sunhv.c +++ b/drivers/serial/sunhv.c @@ -440,8 +440,16 @@ static void sunhv_console_write_paged(struct console *con, const char *s, unsign { struct uart_port *port = sunhv_port; unsigned long flags; + int locked = 1; + + local_irq_save(flags); + if (port->sysrq) { + locked = 0; + } else if (oops_in_progress) { + locked = spin_trylock(&port->lock); + } else + spin_lock(&port->lock); - spin_lock_irqsave(&port->lock, flags); while (n > 0) { unsigned long ra = __pa(con_write_page); unsigned long page_bytes; @@ -469,7 +477,10 @@ static void sunhv_console_write_paged(struct console *con, const char *s, unsign ra += written; } } - spin_unlock_irqrestore(&port->lock, flags); + + if (locked) + spin_unlock(&port->lock); + local_irq_restore(flags); } static inline void sunhv_console_putchar(struct uart_port *port, char c) @@ -488,7 +499,15 @@ static void sunhv_console_write_bychar(struct console *con, const char *s, unsig { struct uart_port *port = sunhv_port; unsigned long flags; - int i; + int i, locked = 1; + + local_irq_save(flags); + if (port->sysrq) { + locked = 0; + } else if (oops_in_progress) { + locked = spin_trylock(&port->lock); + } else + spin_lock(&port->lock); spin_lock_irqsave(&port->lock, flags); for (i = 0; i < n; i++) { @@ -496,7 +515,10 @@ static void sunhv_console_write_bychar(struct console *con, const char *s, unsig sunhv_console_putchar(port, '\r'); sunhv_console_putchar(port, *s++); } - spin_unlock_irqrestore(&port->lock, flags); + + if (locked) + spin_unlock(&port->lock); + local_irq_restore(flags); } static struct console sunhv_console = { diff --git a/drivers/serial/sunsab.c b/drivers/serial/sunsab.c index deb9ab4b5a0b..8a0f9e4408d4 100644 --- a/drivers/serial/sunsab.c +++ b/drivers/serial/sunsab.c @@ -860,22 +860,31 @@ static int num_channels; static void sunsab_console_putchar(struct uart_port *port, int c) { struct uart_sunsab_port *up = (struct uart_sunsab_port *)port; - unsigned long flags; - - spin_lock_irqsave(&up->port.lock, flags); sunsab_tec_wait(up); writeb(c, &up->regs->w.tic); - - spin_unlock_irqrestore(&up->port.lock, flags); } static void sunsab_console_write(struct console *con, const char *s, unsigned n) { struct uart_sunsab_port *up = &sunsab_ports[con->index]; + unsigned long flags; + int locked = 1; + + local_irq_save(flags); + if (up->port.sysrq) { + locked = 0; + } else if (oops_in_progress) { + locked = spin_trylock(&up->port.lock); + } else + spin_lock(&up->port.lock); uart_console_write(&up->port, s, n, sunsab_console_putchar); sunsab_tec_wait(up); + + if (locked) + spin_unlock(&up->port.lock); + local_irq_restore(flags); } static int sunsab_console_setup(struct console *con, char *options) diff --git a/drivers/serial/sunsu.c b/drivers/serial/sunsu.c index 2a63cdba3208..26d720baf88c 100644 --- a/drivers/serial/sunsu.c +++ b/drivers/serial/sunsu.c @@ -1288,7 +1288,17 @@ static void sunsu_console_write(struct console *co, const char *s, unsigned int count) { struct uart_sunsu_port *up = &sunsu_ports[co->index]; + unsigned long flags; unsigned int ier; + int locked = 1; + + local_irq_save(flags); + if (up->port.sysrq) { + locked = 0; + } else if (oops_in_progress) { + locked = spin_trylock(&up->port.lock); + } else + spin_lock(&up->port.lock); /* * First save the UER then disable the interrupts @@ -1304,6 +1314,10 @@ static void sunsu_console_write(struct console *co, const char *s, */ wait_for_xmitr(up); serial_out(up, UART_IER, ier); + + if (locked) + spin_unlock(&up->port.lock); + local_irq_restore(flags); } /* diff --git a/drivers/serial/sunzilog.c b/drivers/serial/sunzilog.c index 15b6e1cb040b..0a3e10a4a35d 100644 --- a/drivers/serial/sunzilog.c +++ b/drivers/serial/sunzilog.c @@ -9,7 +9,7 @@ * C. Dost, Pete Zaitcev, Ted Ts'o and Alex Buell for their * work there. * - * Copyright (C) 2002, 2006 David S. Miller (davem@davemloft.net) + * Copyright (C) 2002, 2006, 2007 David S. Miller (davem@davemloft.net) */ #include <linux/module.h> @@ -1151,11 +1151,22 @@ sunzilog_console_write(struct console *con, const char *s, unsigned int count) { struct uart_sunzilog_port *up = &sunzilog_port_table[con->index]; unsigned long flags; + int locked = 1; + + local_irq_save(flags); + if (up->port.sysrq) { + locked = 0; + } else if (oops_in_progress) { + locked = spin_trylock(&up->port.lock); + } else + spin_lock(&up->port.lock); - spin_lock_irqsave(&up->port.lock, flags); uart_console_write(&up->port, s, count, sunzilog_putchar); udelay(2); - spin_unlock_irqrestore(&up->port.lock, flags); + + if (locked) + spin_unlock(&up->port.lock); + local_irq_restore(flags); } static int __init sunzilog_console_setup(struct console *con, char *options) |