stallion: prune lock_kernel calls
Remove unneeded tty layer lock kernel bits. Relock the needed bits using the
port mutex. The istallion still has brd state races but those are not new
or introduced by the removal of the lock_kernel logic.
Signed-off-by: Alan Cox <alan@linux.intel.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/drivers/char/istallion.c b/drivers/char/istallion.c
index 4e395c9..750650c 100644
--- a/drivers/char/istallion.c
+++ b/drivers/char/istallion.c
@@ -14,6 +14,7 @@
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
+ * FIXME: brdp->state needs proper locking.
*/
/*****************************************************************************/
@@ -4011,6 +4012,7 @@
return -ENODEV;
memset(&stli_brdstats, 0, sizeof(combrd_t));
+
stli_brdstats.brd = brdp->brdnr;
stli_brdstats.type = brdp->brdtype;
stli_brdstats.hwid = 0;
@@ -4076,10 +4078,13 @@
if (brdp == NULL)
return -ENODEV;
+ mutex_lock(&portp->port.mutex);
if (brdp->state & BST_STARTED) {
if ((rc = stli_cmdwait(brdp, portp, A_GETSTATS,
- &stli_cdkstats, sizeof(asystats_t), 1)) < 0)
+ &stli_cdkstats, sizeof(asystats_t), 1)) < 0) {
+ mutex_unlock(&portp->port.mutex);
return rc;
+ }
} else {
memset(&stli_cdkstats, 0, sizeof(asystats_t));
}
@@ -4124,6 +4129,7 @@
stli_comstats.modem = stli_cdkstats.dcdcnt;
stli_comstats.hwid = stli_cdkstats.hwid;
stli_comstats.signals = stli_mktiocm(stli_cdkstats.signals);
+ mutex_unlock(&portp->port.mutex);
return 0;
}
@@ -4186,15 +4192,20 @@
if (!brdp)
return -ENODEV;
+ mutex_lock(&portp->port.mutex);
+
if (brdp->state & BST_STARTED) {
- if ((rc = stli_cmdwait(brdp, portp, A_CLEARSTATS, NULL, 0, 0)) < 0)
+ if ((rc = stli_cmdwait(brdp, portp, A_CLEARSTATS, NULL, 0, 0)) < 0) {
+ mutex_unlock(&portp->port.mutex);
return rc;
+ }
}
memset(&stli_comstats, 0, sizeof(comstats_t));
stli_comstats.brd = portp->brdnr;
stli_comstats.panel = portp->panelnr;
stli_comstats.port = portp->portnr;
+ mutex_unlock(&portp->port.mutex);
if (copy_to_user(cp, &stli_comstats, sizeof(comstats_t)))
return -EFAULT;
@@ -4266,8 +4277,6 @@
done = 0;
rc = 0;
- lock_kernel();
-
switch (cmd) {
case COM_GETPORTSTATS:
rc = stli_getportstats(NULL, NULL, argp);
@@ -4290,8 +4299,6 @@
done++;
break;
}
- unlock_kernel();
-
if (done)
return rc;
@@ -4308,8 +4315,6 @@
if (brdp->state == 0)
return -ENODEV;
- lock_kernel();
-
switch (cmd) {
case STL_BINTR:
EBRDINTR(brdp);
@@ -4332,7 +4337,6 @@
rc = -ENOIOCTLCMD;
break;
}
- unlock_kernel();
return rc;
}
diff --git a/drivers/char/stallion.c b/drivers/char/stallion.c
index 6049fd7..f2167f8 100644
--- a/drivers/char/stallion.c
+++ b/drivers/char/stallion.c
@@ -807,7 +807,6 @@
timeout = HZ;
tend = jiffies + timeout;
- lock_kernel();
while (stl_datastate(portp)) {
if (signal_pending(current))
break;
@@ -815,7 +814,6 @@
if (time_after_eq(jiffies, tend))
break;
}
- unlock_kernel();
}
/*****************************************************************************/
@@ -1029,6 +1027,8 @@
pr_debug("stl_getserial(portp=%p,sp=%p)\n", portp, sp);
memset(&sio, 0, sizeof(struct serial_struct));
+
+ mutex_lock(&portp->port.mutex);
sio.line = portp->portnr;
sio.port = portp->ioaddr;
sio.flags = portp->port.flags;
@@ -1048,6 +1048,7 @@
brdp = stl_brds[portp->brdnr];
if (brdp != NULL)
sio.irq = brdp->irq;
+ mutex_unlock(&portp->port.mutex);
return copy_to_user(sp, &sio, sizeof(struct serial_struct)) ? -EFAULT : 0;
}
@@ -1069,12 +1070,15 @@
if (copy_from_user(&sio, sp, sizeof(struct serial_struct)))
return -EFAULT;
+ mutex_lock(&portp->port.mutex);
if (!capable(CAP_SYS_ADMIN)) {
if ((sio.baud_base != portp->baud_base) ||
(sio.close_delay != portp->close_delay) ||
((sio.flags & ~ASYNC_USR_MASK) !=
- (portp->port.flags & ~ASYNC_USR_MASK)))
+ (portp->port.flags & ~ASYNC_USR_MASK))) {
+ mutex_unlock(&portp->port.mutex);
return -EPERM;
+ }
}
portp->port.flags = (portp->port.flags & ~ASYNC_USR_MASK) |
@@ -1083,6 +1087,7 @@
portp->close_delay = sio.close_delay;
portp->closing_wait = sio.closing_wait;
portp->custom_divisor = sio.custom_divisor;
+ mutex_unlock(&portp->port.mutex);
stl_setport(portp, tty->termios);
return 0;
}
@@ -1147,8 +1152,6 @@
rc = 0;
- lock_kernel();
-
switch (cmd) {
case TIOCGSERIAL:
rc = stl_getserial(portp, argp);
@@ -1173,7 +1176,6 @@
rc = -ENOIOCTLCMD;
break;
}
- unlock_kernel();
return rc;
}
@@ -2327,6 +2329,7 @@
return -ENODEV;
}
+ mutex_lock(&portp->port.mutex);
portp->stats.state = portp->istate;
portp->stats.flags = portp->port.flags;
portp->stats.hwid = portp->hwid;
@@ -2358,6 +2361,7 @@
(STL_TXBUFSIZE - (tail - head));
portp->stats.signals = (unsigned long) stl_getsignals(portp);
+ mutex_unlock(&portp->port.mutex);
return copy_to_user(cp, &portp->stats,
sizeof(comstats_t)) ? -EFAULT : 0;
@@ -2382,10 +2386,12 @@
return -ENODEV;
}
+ mutex_lock(&portp->port.mutex);
memset(&portp->stats, 0, sizeof(comstats_t));
portp->stats.brd = portp->brdnr;
portp->stats.panel = portp->panelnr;
portp->stats.port = portp->portnr;
+ mutex_unlock(&portp->port.mutex);
return copy_to_user(cp, &portp->stats,
sizeof(comstats_t)) ? -EFAULT : 0;
}
@@ -2451,7 +2457,6 @@
return -ENODEV;
rc = 0;
- lock_kernel();
switch (cmd) {
case COM_GETPORTSTATS:
rc = stl_getportstats(NULL, NULL, argp);
@@ -2472,7 +2477,6 @@
rc = -ENOIOCTLCMD;
break;
}
- unlock_kernel();
return rc;
}