From: Alan Cox <alan@linux.intel.com>
To: linux-kernel@vger.kernel.org
Subject: [PATCH 05/14] stallion: prune lock_kernel calls
Date: Thu, 01 Apr 2010 17:05:19 +0100 [thread overview]
Message-ID: <20100401160504.8882.37742.stgit@localhost.localdomain> (raw)
In-Reply-To: <20100401155513.8882.54006.stgit@localhost.localdomain>
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>
---
drivers/char/istallion.c | 24 +++++++++++++++---------
drivers/char/stallion.c | 20 ++++++++++++--------
2 files changed, 27 insertions(+), 17 deletions(-)
diff --git a/drivers/char/istallion.c b/drivers/char/istallion.c
index 4cd6c52..3699e30 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.
*/
/*****************************************************************************/
@@ -4009,6 +4010,8 @@ static int stli_getbrdstats(combrd_t __user *bp)
return -ENODEV;
memset(&stli_brdstats, 0, sizeof(combrd_t));
+
+ mutex_lock(&portp->port.mutex);
stli_brdstats.brd = brdp->brdnr;
stli_brdstats.type = brdp->brdtype;
stli_brdstats.hwid = 0;
@@ -4022,6 +4025,7 @@ static int stli_getbrdstats(combrd_t __user *bp)
stli_brdstats.panels[i].hwid = brdp->panelids[i];
stli_brdstats.panels[i].nrports = brdp->panels[i];
}
+ mutex_unlock(&portp->port.mutex);
if (copy_to_user(bp, &stli_brdstats, sizeof(combrd_t)))
return -EFAULT;
@@ -4074,10 +4078,13 @@ static int stli_portcmdstats(struct tty_struct *tty, struct stliport *portp)
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));
}
@@ -4122,6 +4129,7 @@ static int stli_portcmdstats(struct tty_struct *tty, struct stliport *portp)
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;
}
@@ -4184,15 +4192,20 @@ static int stli_clrportstats(struct stliport *portp, comstats_t __user *cp)
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;
@@ -4264,8 +4277,6 @@ static long stli_memioctl(struct file *fp, unsigned int cmd, unsigned long arg)
done = 0;
rc = 0;
- lock_kernel();
-
switch (cmd) {
case COM_GETPORTSTATS:
rc = stli_getportstats(NULL, NULL, argp);
@@ -4288,8 +4299,6 @@ static long stli_memioctl(struct file *fp, unsigned int cmd, unsigned long arg)
done++;
break;
}
- unlock_kernel();
-
if (done)
return rc;
@@ -4306,8 +4315,6 @@ static long stli_memioctl(struct file *fp, unsigned int cmd, unsigned long arg)
if (brdp->state == 0)
return -ENODEV;
- lock_kernel();
-
switch (cmd) {
case STL_BINTR:
EBRDINTR(brdp);
@@ -4330,7 +4337,6 @@ static long stli_memioctl(struct file *fp, unsigned int cmd, unsigned long arg)
rc = -ENOIOCTLCMD;
break;
}
- unlock_kernel();
return rc;
}
diff --git a/drivers/char/stallion.c b/drivers/char/stallion.c
index 0e511d6..db5c418 100644
--- a/drivers/char/stallion.c
+++ b/drivers/char/stallion.c
@@ -807,7 +807,6 @@ static void stl_waituntilsent(struct tty_struct *tty, int timeout)
timeout = HZ;
tend = jiffies + timeout;
- lock_kernel();
while (stl_datastate(portp)) {
if (signal_pending(current))
break;
@@ -815,7 +814,6 @@ static void stl_waituntilsent(struct tty_struct *tty, int timeout)
if (time_after_eq(jiffies, tend))
break;
}
- unlock_kernel();
}
/*****************************************************************************/
@@ -1028,6 +1026,8 @@ static int stl_getserial(struct stlport *portp, struct serial_struct __user *sp)
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;
@@ -1047,6 +1047,7 @@ static int stl_getserial(struct stlport *portp, struct serial_struct __user *sp)
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;
}
@@ -1068,12 +1069,15 @@ static int stl_setserial(struct tty_struct *tty, struct serial_struct __user *sp
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) |
@@ -1082,6 +1086,7 @@ static int stl_setserial(struct tty_struct *tty, struct serial_struct __user *sp
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;
}
@@ -1146,8 +1151,6 @@ static int stl_ioctl(struct tty_struct *tty, struct file *file, unsigned int cmd
rc = 0;
- lock_kernel();
-
switch (cmd) {
case TIOCGSERIAL:
rc = stl_getserial(portp, argp);
@@ -1172,7 +1175,6 @@ static int stl_ioctl(struct tty_struct *tty, struct file *file, unsigned int cmd
rc = -ENOIOCTLCMD;
break;
}
- unlock_kernel();
return rc;
}
@@ -2326,6 +2328,7 @@ static int stl_getportstats(struct tty_struct *tty, struct stlport *portp, comst
return -ENODEV;
}
+ mutex_lock(&portp->port.mutex);
portp->stats.state = portp->istate;
portp->stats.flags = portp->port.flags;
portp->stats.hwid = portp->hwid;
@@ -2357,6 +2360,7 @@ static int stl_getportstats(struct tty_struct *tty, struct stlport *portp, comst
(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;
@@ -2381,10 +2385,12 @@ static int stl_clrportstats(struct stlport *portp, comstats_t __user *cp)
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;
}
@@ -2450,7 +2456,6 @@ static long stl_memioctl(struct file *fp, unsigned int cmd, unsigned long arg)
return -ENODEV;
rc = 0;
- lock_kernel();
switch (cmd) {
case COM_GETPORTSTATS:
rc = stl_getportstats(NULL, NULL, argp);
@@ -2471,7 +2476,6 @@ static long stl_memioctl(struct file *fp, unsigned int cmd, unsigned long arg)
rc = -ENOIOCTLCMD;
break;
}
- unlock_kernel();
return rc;
}
next prev parent reply other threads:[~2010-04-01 16:34 UTC|newest]
Thread overview: 18+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-04-01 16:04 [RFC PATCH 00/14] Some BKL killing in the serial drivers Alan Cox
2010-04-01 16:04 ` [PATCH 01/14] tty: serial - fix tty referencing in set_ldisc Alan Cox
2010-04-01 16:04 ` [PATCH 02/14] tty: serial - fix tty back references in termios Alan Cox
2010-04-01 16:04 ` [PATCH 03/14] tty: serial - fix various misuses/mishandlings of port->tty Alan Cox
2010-04-01 16:04 ` [PATCH 04/14] vc: Locking clean up Alan Cox
2010-04-30 20:30 ` Arnd Bergmann
2010-04-01 16:05 ` Alan Cox [this message]
2010-04-29 21:29 ` [PATCH 05/14] stallion: prune lock_kernel calls Arnd Bergmann
2010-04-30 19:32 ` Alan Cox
2010-04-01 16:05 ` [PATCH 06/14] istallion: use bit ops for the board flags Alan Cox
2010-04-01 16:05 ` [PATCH 07/14] riscom8: kill use of lock_kernel Alan Cox
2010-04-01 16:05 ` [PATCH 08/14] isicom: kill off the BKL Alan Cox
2010-04-01 16:06 ` [PATCH 09/14] rocket: kill BKL Alan Cox
2010-04-01 16:06 ` [PATCH 10/14] synclink: kill the big kernel lock Alan Cox
2010-04-01 16:06 ` [PATCH 11/14] cyclades: Kill off BKL usage Alan Cox
2010-04-01 16:06 ` [PATCH 12/14] epca: Kill the big kernel lock Alan Cox
2010-04-01 16:07 ` [PATCH 13/14] specialix; Kill the BKL Alan Cox
2010-04-01 16:07 ` [PATCH 14/14] synclink: reworking locking a bit Alan Cox
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