[PATCH 13/67] stallion: prune lock_kernel calls

Previous message: [thread] [date] [author]
Next message: [thread] [date] [author]
From: Greg Kroah-Hartman
Date: Thursday, August 5, 2010 - 3:22 pm

From: Alan Cox <alan@linux.intel.com>

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>
---
 drivers/char/istallion.c |   22 +++++++++++++---------
 drivers/char/stallion.c  |   20 ++++++++++++--------
 2 files changed, 25 insertions(+), 17 deletions(-)

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 @@ static int stli_getbrdstats(combrd_t __user *bp)
 		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 @@ 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));
 	}
@@ -4124,6 +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;
 }
@@ -4186,15 +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;
@@ -4266,8 +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);
@@ -4290,8 +4299,6 @@ static long stli_memioctl(struct file *fp, unsigned int cmd, unsigned long arg)
 		done++;
 		break;
 	}
-	unlock_kernel();
-
 	if (done)
 		return rc;
 
@@ -4308,8 +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);
@@ -4332,7 +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 6049fd7..f2167f8 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();
 }
 
 /*****************************************************************************/
@@ -1029,6 +1027,8 @@ 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;
@@ -1048,6 +1048,7 @@ 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;
 }
@@ -1069,12 +1070,15 @@ 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) |
@@ -1083,6 +1087,7 @@ 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;
 }
@@ -1147,8 +1152,6 @@ 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);
@@ -1173,7 +1176,6 @@ static int stl_ioctl(struct tty_struct *tty, struct file *file, unsigned int cmd
 		rc = -ENOIOCTLCMD;
 		break;
 	}
-	unlock_kernel();
 	return rc;
 }
 
@@ -2327,6 +2329,7 @@ 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;
@@ -2358,6 +2361,7 @@ 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;
@@ -2382,10 +2386,12 @@ 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;
 }
@@ -2451,7 +2457,6 @@ 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);
@@ -2472,7 +2477,6 @@ static long stl_memioctl(struct file *fp, unsigned int cmd, unsigned long arg)
 		rc = -ENOIOCTLCMD;
 		break;
 	}
-	unlock_kernel();
 	return rc;
 }
 
-- 
1.7.2

--
Previous message: [thread] [date] [author]
Next message: [thread] [date] [author]

Messages in current thread:
[GIT PATCH] TTY patches for 2.6.36, Greg KH, (Thu Aug 5, 2:35 pm)
[PATCH 01/67] n_gsm.c: removed duplicated #includes, Greg Kroah-Hartman, (Thu Aug 5, 3:22 pm)
[PATCH 02/67] serial: There's no config CONSOLE, Greg Kroah-Hartman, (Thu Aug 5, 3:22 pm)
[PATCH 03/67] vt: clean up the code - use kernel library, Greg Kroah-Hartman, (Thu Aug 5, 3:22 pm)
[PATCH 04/67] serial: add UART_CAP_EFR and UART_CAP_SLEEP ..., Greg Kroah-Hartman, (Thu Aug 5, 3:22 pm)
[PATCH 05/67] mrst_max3110: add UART driver for Max3110 on ..., Greg Kroah-Hartman, (Thu Aug 5, 3:22 pm)
[PATCH 06/67] max3110 sanity check a register, Greg Kroah-Hartman, (Thu Aug 5, 3:22 pm)
[PATCH 07/67] serial: replace open coded mutex with a real ..., Greg Kroah-Hartman, (Thu Aug 5, 3:22 pm)
[PATCH 08/67] serial: fix wakup races in the mrst_max3110 ..., Greg Kroah-Hartman, (Thu Aug 5, 3:22 pm)
[PATCH 09/67] tty: Remove Hayes ESP ioctls, Greg Kroah-Hartman, (Thu Aug 5, 3:22 pm)
[PATCH 10/67] tty: remove remaining Hayes ESP ioctls, Greg Kroah-Hartman, (Thu Aug 5, 3:22 pm)
[PATCH 11/67] tty: Add EXTPROC support for LINEMODE, Greg Kroah-Hartman, (Thu Aug 5, 3:22 pm)
[PATCH 12/67] vt/console: try harder to print output when ..., Greg Kroah-Hartman, (Thu Aug 5, 3:22 pm)
[PATCH 13/67] stallion: prune lock_kernel calls, Greg Kroah-Hartman, (Thu Aug 5, 3:22 pm)
[PATCH 14/67] istallion: use bit ops for the board flags, Greg Kroah-Hartman, (Thu Aug 5, 3:22 pm)
[PATCH 15/67] riscom8: kill use of lock_kernel, Greg Kroah-Hartman, (Thu Aug 5, 3:22 pm)
[PATCH 16/67] isicom: kill off the BKL, Greg Kroah-Hartman, (Thu Aug 5, 3:22 pm)
[PATCH 17/67] rocket: kill BKL, Greg Kroah-Hartman, (Thu Aug 5, 3:22 pm)
[PATCH 18/67] synclink: kill the big kernel lock, Greg Kroah-Hartman, (Thu Aug 5, 3:22 pm)
[PATCH 19/67] cyclades: Kill off BKL usage, Greg Kroah-Hartman, (Thu Aug 5, 3:22 pm)
[PATCH 20/67] epca: Kill the big kernel lock, Greg Kroah-Hartman, (Thu Aug 5, 3:22 pm)
[PATCH 21/67] specialix: Kill the BKL, Greg Kroah-Hartman, (Thu Aug 5, 3:22 pm)
[PATCH 22/67] tty: Fix the digi acceleport driver NULL checks, Greg Kroah-Hartman, (Thu Aug 5, 3:22 pm)
[PATCH 23/67] synclink: reworking locking a bit, Greg Kroah-Hartman, (Thu Aug 5, 3:22 pm)
[PATCH 24/67] tty: serial - fix various misuses/mishandlin ..., Greg Kroah-Hartman, (Thu Aug 5, 3:22 pm)
[PATCH 25/67] tty: serial - fix tty back references in termios, Greg Kroah-Hartman, (Thu Aug 5, 3:22 pm)
[PATCH 26/67] tty: serial - fix tty referencing in set_ldisc, Greg Kroah-Hartman, (Thu Aug 5, 3:22 pm)
[PATCH 27/67] vc: Locking clean up, Greg Kroah-Hartman, (Thu Aug 5, 3:22 pm)
[PATCH 28/67] tty: Make vt's have a tty_port, Greg Kroah-Hartman, (Thu Aug 5, 3:22 pm)
[PATCH 29/67] tty: Move the vt_tty field from the vc_data ..., Greg Kroah-Hartman, (Thu Aug 5, 3:22 pm)
[PATCH 30/67] serial: Change the wait for carrier locking, Greg Kroah-Hartman, (Thu Aug 5, 3:22 pm)
[PATCH 31/67] serial: add port helpers, Greg Kroah-Hartman, (Thu Aug 5, 3:22 pm)
[PATCH 32/67] serial: trim locking on the helpers, Greg Kroah-Hartman, (Thu Aug 5, 3:22 pm)
[PATCH 33/67] serial: Use block_til_ready helper, Greg Kroah-Hartman, (Thu Aug 5, 3:23 pm)
[PATCH 34/67] serial: fix termios settings in open, Greg Kroah-Hartman, (Thu Aug 5, 3:23 pm)
[PATCH 35/67] tty: replace BKL with a new tty_lock, Greg Kroah-Hartman, (Thu Aug 5, 3:23 pm)
[PATCH 36/67] tty: never hold BTM while getting tty_mutex, Greg Kroah-Hartman, (Thu Aug 5, 3:23 pm)
[PATCH 37/67] tty: fix console_sem lock order, Greg Kroah-Hartman, (Thu Aug 5, 3:23 pm)
[PATCH 38/67] cdc-acm: remove dead code, Greg Kroah-Hartman, (Thu Aug 5, 3:23 pm)
[PATCH 39/67] tty: introduce wait_event_interruptible_tty, Greg Kroah-Hartman, (Thu Aug 5, 3:23 pm)
[PATCH 40/67] tty: reorder ldisc locking, Greg Kroah-Hartman, (Thu Aug 5, 3:23 pm)
[PATCH 41/67] tty: untangle locking of wait_until_sent, Greg Kroah-Hartman, (Thu Aug 5, 3:23 pm)
[PATCH 42/67] tty: remove tty_lock_nested, Greg Kroah-Hartman, (Thu Aug 5, 3:23 pm)
[PATCH 43/67] tty: implement BTM as mutex instead of BKL, Greg Kroah-Hartman, (Thu Aug 5, 3:23 pm)
[PATCH 44/67] tty: release BTM while sleeping in block_til ..., Greg Kroah-Hartman, (Thu Aug 5, 3:23 pm)
[PATCH 45/67] 8250: fix set_ldisc operation, Greg Kroah-Hartman, (Thu Aug 5, 3:23 pm)
[PATCH 46/67] tty: avoid recursive BTM in pty_close, Greg Kroah-Hartman, (Thu Aug 5, 3:23 pm)
[PATCH 47/67] serial: max3107: introduce a max3107 driver, Greg Kroah-Hartman, (Thu Aug 5, 3:23 pm)
[PATCH 48/67] serial: max3107: Abstract out the platform s ..., Greg Kroah-Hartman, (Thu Aug 5, 3:23 pm)
[PATCH 49/67] tty_io: remove casts from void*, Greg Kroah-Hartman, (Thu Aug 5, 3:23 pm)
[PATCH 50/67] vt: Fix warning: statement with no effect du ..., Greg Kroah-Hartman, (Thu Aug 5, 3:23 pm)
[PATCH 51/67] serial: crisv10: formatting of pointers in p ..., Greg Kroah-Hartman, (Thu Aug 5, 3:23 pm)
[PATCH 53/67] serial: fix missing bit coverage of ASYNC_FLAGS, Greg Kroah-Hartman, (Thu Aug 5, 3:23 pm)
[PATCH 54/67] serial: general fixes in the serial_rs485 st ..., Greg Kroah-Hartman, (Thu Aug 5, 3:23 pm)
[PATCH 55/67] serial: mcf: don't take spinlocks in already ..., Greg Kroah-Hartman, (Thu Aug 5, 3:23 pm)
[PATCH 56/67] serial: MMIO32 support for 8250_early.c, Greg Kroah-Hartman, (Thu Aug 5, 3:23 pm)
[PATCH 57/67] timbuart: use __devinit and __devexit macros ..., Greg Kroah-Hartman, (Thu Aug 5, 3:23 pm)
[PATCH 58/67] serial: 68328serial.c: remove dead (ALMA_ANS ..., Greg Kroah-Hartman, (Thu Aug 5, 3:23 pm)
[PATCH 59/67] serial: add support for OX16PCI958 card, Greg Kroah-Hartman, (Thu Aug 5, 3:23 pm)
[PATCH 60/67] mxser: remove unnesesary NULL check, Greg Kroah-Hartman, (Thu Aug 5, 3:23 pm)
[PATCH 61/67] hsu: driver for Medfield High Speed UART device, Greg Kroah-Hartman, (Thu Aug 5, 3:23 pm)
[PATCH 62/67] hsu: add a periodic timer to check dma rx ch ..., Greg Kroah-Hartman, (Thu Aug 5, 3:23 pm)
[PATCH 63/67] hsu: some code cleanup, Greg Kroah-Hartman, (Thu Aug 5, 3:23 pm)
[PATCH 64/67] hsu: call PCI pm hooks in suspend/resume fun ..., Greg Kroah-Hartman, (Thu Aug 5, 3:23 pm)
[PATCH 65/67] serial: max3107: Fix gpiolib support, Greg Kroah-Hartman, (Thu Aug 5, 3:23 pm)
Re: [GIT PATCH] TTY patches for 2.6.36, Linus Torvalds, (Fri Aug 6, 11:40 am)
Re: [GIT PATCH] TTY patches for 2.6.36, Greg KH, (Fri Aug 6, 11:51 am)
Re: [GIT PATCH] TTY patches for 2.6.36, Greg KH, (Fri Aug 6, 12:37 pm)
Re: [GIT PATCH] TTY patches for 2.6.36, Linus Torvalds, (Fri Aug 6, 12:38 pm)
[PATCH retry] tty: implement BTM as mutex instead of BKL, Arnd Bergmann, (Fri Aug 6, 12:40 pm)
Re: [GIT PATCH] TTY patches for 2.6.36, Arnd Bergmann, (Fri Aug 6, 12:40 pm)
Re: [GIT PATCH] TTY patches for 2.6.36, Alan Cox, (Fri Aug 6, 12:45 pm)
Re: [GIT PATCH] TTY patches for 2.6.36, Arnd Bergmann, (Fri Aug 6, 12:58 pm)
Re: [GIT PATCH] TTY patches for 2.6.36, Linus Torvalds, (Fri Aug 6, 1:11 pm)
Re: [GIT PATCH] TTY patches for 2.6.36, Arnd Bergmann, (Fri Aug 6, 1:19 pm)
Re: [GIT PATCH] TTY patches for 2.6.36, Greg KH, (Fri Aug 6, 1:22 pm)
Re: [GIT PATCH] TTY patches for 2.6.36, Andy Whitcroft, (Mon Aug 9, 9:06 am)
Re: [GIT PATCH] TTY patches for 2.6.36, Arnd Bergmann, (Mon Aug 9, 11:38 am)
Re: [GIT PATCH] TTY patches for 2.6.36, Alan Cox, (Mon Aug 9, 12:24 pm)
Re: [GIT PATCH] TTY patches for 2.6.36, Andy Whitcroft, (Tue Aug 10, 12:31 am)