tty: moxa: split open lock
moxa_openlock is used for several situations where we want to handle the
case of an ioctl that crosses many ports (not just the open tty), and also
cases where an open races a deinit (eg a pci unplug) and we hangup a port
before we can cope with that.
The non open race cases can use the moxa_lock spinlock. This simplifies sorting
out the remaining mess.
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/drivers/char/moxa.c b/drivers/char/moxa.c
index d53fac5..63ee3bb 100644
--- a/drivers/char/moxa.c
+++ b/drivers/char/moxa.c
@@ -163,6 +163,7 @@
static unsigned int moxaFuncTout = HZ / 2;
static unsigned int moxaLowWaterChk;
static DEFINE_MUTEX(moxa_openlock);
+static DEFINE_SPINLOCK(moxa_lock);
/* Variables for insmod */
#ifdef MODULE
static unsigned long baseaddr[MAX_BOARDS];
@@ -313,22 +314,20 @@
struct moxa_port *p;
unsigned int i, j;
- mutex_lock(&moxa_openlock);
for (i = 0; i < MAX_BOARDS; i++) {
p = moxa_boards[i].ports;
for (j = 0; j < MAX_PORTS_PER_BOARD; j++, p++, argm++) {
memset(&tmp, 0, sizeof(tmp));
+ spin_lock_bh(&moxa_lock);
if (moxa_boards[i].ready) {
tmp.inq = MoxaPortRxQueue(p);
tmp.outq = MoxaPortTxQueue(p);
}
- if (copy_to_user(argm, &tmp, sizeof(tmp))) {
- mutex_unlock(&moxa_openlock);
+ spin_unlock_bh(&moxa_lock);
+ if (copy_to_user(argm, &tmp, sizeof(tmp)))
return -EFAULT;
- }
}
}
- mutex_unlock(&moxa_openlock);
break;
} case MOXA_GET_OQUEUE:
status = MoxaPortTxQueue(ch);
@@ -344,16 +343,20 @@
struct moxa_port *p;
unsigned int i, j;
- mutex_lock(&moxa_openlock);
for (i = 0; i < MAX_BOARDS; i++) {
p = moxa_boards[i].ports;
for (j = 0; j < MAX_PORTS_PER_BOARD; j++, p++, argm++) {
struct tty_struct *ttyp;
memset(&tmp, 0, sizeof(tmp));
- if (!moxa_boards[i].ready)
+ spin_lock_bh(&moxa_lock);
+ if (!moxa_boards[i].ready) {
+ spin_unlock_bh(&moxa_lock);
goto copy;
+ }
status = MoxaPortLineStatus(p);
+ spin_unlock_bh(&moxa_lock);
+
if (status & 1)
tmp.cts = 1;
if (status & 2)
@@ -368,13 +371,10 @@
tmp.cflag = ttyp->termios->c_cflag;
tty_kref_put(tty);
copy:
- if (copy_to_user(argm, &tmp, sizeof(tmp))) {
- mutex_unlock(&moxa_openlock);
+ if (copy_to_user(argm, &tmp, sizeof(tmp)))
return -EFAULT;
- }
}
}
- mutex_unlock(&moxa_openlock);
break;
}
case TIOCGSERIAL:
@@ -427,7 +427,6 @@
static struct tty_driver *moxaDriver;
static DEFINE_TIMER(moxaTimer, moxa_poll, 0, 0);
-static DEFINE_SPINLOCK(moxa_lock);
/*
* HW init