Prev: [PATCH 28/68] tty: Make vt's have a tty_port
Next: [PATCH 23/68] synclink: reworking locking a bit
From: Greg Kroah-Hartman on 10 Aug 2010 18:20
From: Alan Cox <alan(a)linux.intel.com>

We don't need it while waiting and we can lock the ioctls using the port
mutex. While at it eliminate use of the hangup mutex and switch to the port
mutex.

Signed-off-by: Alan Cox <alan(a)linux.intel.com>
Cc: Arnd Bergmann <arnd(a)arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)suse.de>
---
drivers/char/synclink.c | 19 ++++++-----
drivers/char/synclink_gt.c | 78 +++++++++++++++++++-------------------------
drivers/char/synclinkmp.c | 32 +++++++-----------
3 files changed, 56 insertions(+), 73 deletions(-)

diff --git a/drivers/char/synclink.c b/drivers/char/synclink.c
index 0658fc5..2b03d4d 100644
--- a/drivers/char/synclink.c
+++ b/drivers/char/synclink.c
@@ -81,7 +81,6 @@
#include <linux/mm.h>
#include <linux/seq_file.h>
#include <linux/slab.h>
-#include <linux/smp_lock.h>
#include <linux/delay.h>
#include <linux/netdevice.h>
#include <linux/vmalloc.h>
@@ -2436,7 +2435,9 @@ static int mgsl_get_stats(struct mgsl_struct * info, struct mgsl_icount __user *
if (!user_icount) {
memset(&info->icount, 0, sizeof(info->icount));
} else {
+ mutex_lock(&info->port.mutex);
COPY_TO_USER(err, user_icount, &info->icount, sizeof(struct mgsl_icount));
+ mutex_unlock(&info->port.mutex);
if (err)
return -EFAULT;
}
@@ -2461,7 +2462,9 @@ static int mgsl_get_params(struct mgsl_struct * info, MGSL_PARAMS __user *user_p
printk("%s(%d):mgsl_get_params(%s)\n",
__FILE__,__LINE__, info->device_name);

+ mutex_lock(&info->port.mutex);
COPY_TO_USER(err,user_params, &info->params, sizeof(MGSL_PARAMS));
+ mutex_unlock(&info->port.mutex);
if (err) {
if ( debug_level >= DEBUG_LEVEL_INFO )
printk( "%s(%d):mgsl_get_params(%s) user buffer copy failed\n",
@@ -2501,11 +2504,13 @@ static int mgsl_set_params(struct mgsl_struct * info, MGSL_PARAMS __user *new_pa
return -EFAULT;
}

+ mutex_lock(&info->port.mutex);
spin_lock_irqsave(&info->irq_spinlock,flags);
memcpy(&info->params,&tmp_params,sizeof(MGSL_PARAMS));
spin_unlock_irqrestore(&info->irq_spinlock,flags);

mgsl_change_params(info);
+ mutex_unlock(&info->port.mutex);

return 0;

@@ -2935,7 +2940,6 @@ static int mgsl_ioctl(struct tty_struct *tty, struct file * file,
unsigned int cmd, unsigned long arg)
{
struct mgsl_struct * info = tty->driver_data;
- int ret;

if (debug_level >= DEBUG_LEVEL_INFO)
printk("%s(%d):mgsl_ioctl %s cmd=%08X\n", __FILE__,__LINE__,
@@ -2950,10 +2954,7 @@ static int mgsl_ioctl(struct tty_struct *tty, struct file * file,
return -EIO;
}

- lock_kernel();
- ret = mgsl_ioctl_common(info, cmd, arg);
- unlock_kernel();
- return ret;
+ return mgsl_ioctl_common(info, cmd, arg);
}

static int mgsl_ioctl_common(struct mgsl_struct *info, unsigned int cmd, unsigned long arg)
@@ -3109,12 +3110,14 @@ static void mgsl_close(struct tty_struct *tty, struct file * filp)

if (tty_port_close_start(&info->port, tty, filp) == 0)
goto cleanup;
-
+
+ mutex_lock(&info->port.mutex);
if (info->port.flags & ASYNC_INITIALIZED)
mgsl_wait_until_sent(tty, info->timeout);
mgsl_flush_buffer(tty);
tty_ldisc_flush(tty);
shutdown(info);
+ mutex_unlock(&info->port.mutex);

tty_port_close_end(&info->port, tty);
info->port.tty = NULL;
@@ -3162,7 +3165,6 @@ static void mgsl_wait_until_sent(struct tty_struct *tty, int timeout)
* Note: use tight timings here to satisfy the NIST-PCTS.
*/

- lock_kernel();
if ( info->params.data_rate ) {
char_time = info->timeout/(32 * 5);
if (!char_time)
@@ -3192,7 +3194,6 @@ static void mgsl_wait_until_sent(struct tty_struct *tty, int timeout)
break;
}
}
- unlock_kernel();

exit:
if (debug_level >= DEBUG_LEVEL_INFO)
diff --git a/drivers/char/synclink_gt.c b/drivers/char/synclink_gt.c
index 334cf5c..3c7ac6a 100644
--- a/drivers/char/synclink_gt.c
+++ b/drivers/char/synclink_gt.c
@@ -40,8 +40,8 @@
#define DBGBH(fmt) if (debug_level >= DEBUG_LEVEL_BH) printk fmt
#define DBGISR(fmt) if (debug_level >= DEBUG_LEVEL_ISR) printk fmt
#define DBGDATA(info, buf, size, label) if (debug_level >= DEBUG_LEVEL_DATA) trace_block((info), (buf), (size), (label))
-//#define DBGTBUF(info) dump_tbufs(info)
-//#define DBGRBUF(info) dump_rbufs(info)
+/*#define DBGTBUF(info) dump_tbufs(info)*/
+/*#define DBGRBUF(info) dump_rbufs(info)*/


#include <linux/module.h>
@@ -62,7 +62,6 @@
#include <linux/mm.h>
#include <linux/seq_file.h>
#include <linux/slab.h>
-#include <linux/smp_lock.h>
#include <linux/netdevice.h>
#include <linux/vmalloc.h>
#include <linux/init.h>
@@ -901,8 +900,6 @@ static void wait_until_sent(struct tty_struct *tty, int timeout)
* Note: use tight timings here to satisfy the NIST-PCTS.
*/

- lock_kernel();
-
if (info->params.data_rate) {
char_time = info->timeout/(32 * 5);
if (!char_time)
@@ -920,8 +917,6 @@ static void wait_until_sent(struct tty_struct *tty, int timeout)
if (timeout && time_after(jiffies, orig_jiffies + timeout))
break;
}
- unlock_kernel();
-
exit:
DBGINFO(("%s wait_until_sent exit\n", info->device_name));
}
@@ -1041,8 +1036,37 @@ static int ioctl(struct tty_struct *tty, struct file *file,
return -EIO;
}

- lock_kernel();
-
+ switch (cmd) {
+ case MGSL_IOCWAITEVENT:
+ return wait_mgsl_event(info, argp);
+ case TIOCMIWAIT:
+ return modem_input_wait(info,(int)arg);
+ case TIOCGICOUNT:
+ spin_lock_irqsave(&info->lock,flags);
+ cnow = info->icount;
+ spin_unlock_irqrestore(&info->lock,flags);
+ p_cuser = argp;
+ if (put_user(cnow.cts, &p_cuser->cts) ||
+ put_user(cnow.dsr, &p_cuser->dsr) ||
+ put_user(cnow.rng, &p_cuser->rng) ||
+ put_user(cnow.dcd, &p_cuser->dcd) ||
+ put_user(cnow.rx, &p_cuser->rx) ||
+ put_user(cnow.tx, &p_cuser->tx) ||
+ put_user(cnow.frame, &p_cuser->frame) ||
+ put_user(cnow.overrun, &p_cuser->overrun) ||
+ put_user(cnow.parity, &p_cuser->parity) ||
+ put_user(cnow.brk, &p_cuser->brk) ||
+ put_user(cnow.buf_overrun, &p_cuser->buf_overrun))
+ return -EFAULT;
+ return 0;
+ case MGSL_IOCSGPIO:
+ return set_gpio(info, argp);
+ case MGSL_IOCGGPIO:
+ return get_gpio(info, argp);
+ case MGSL_IOCWAITGPIO:
+ return wait_gpio(info, argp);
+ }
+ mutex_lock(&info->port.mutex);
switch (cmd) {
case MGSL_IOCGPARAMS:
ret = get_params(info, argp);
@@ -1068,50 +1092,16 @@ static int ioctl(struct tty_struct *tty, struct file *file,
case MGSL_IOCGSTATS:
ret = get_stats(info, argp);
break;
- case MGSL_IOCWAITEVENT:
- ret = wait_mgsl_event(info, argp);
- break;
- case TIOCMIWAIT:
- ret = modem_input_wait(info,(int)arg);
- break;
case MGSL_IOCGIF:
ret = get_interface(info, argp);
break;
case MGSL_IOCSIF:
ret = set_interface(info,(int)arg);
break;
- case MGSL_IOCSGPIO:
- ret = set_gpio(info, argp);
- break;
- case MGSL_IOCGGPIO:
- ret = get_gpio(info, argp);
- break;
- case MGSL_IOCWAITGPIO:
- ret = wait_gpio(info, argp);
- break;
- case TIOCGICOUNT:
- spin_lock_irqsave(&info->lock,flags);
- cnow = info->icount;
- spin_unlock_irqrestore(&info->lock,flags);
- p_cuser = argp;
- if (put_user(cnow.cts, &p_cuser->cts) ||
- put_user(cnow.dsr, &p_cuser->dsr) ||
- put_user(cnow.rng, &p_cuser->rng) ||
- put_user(cnow.dcd, &p_cuser->dcd) ||
- put_user(cnow.rx, &p_cuser->rx) ||
- put_user(cnow.tx, &p_cuser->tx) ||
- put_user(cnow.frame, &p_cuser->frame) ||
- put_user(cnow.overrun, &p_cuser->overrun) ||
- put_user(cnow.parity, &p_cuser->parity) ||
- put_user(cnow.brk, &p_cuser->brk) ||
- put_user(cnow.buf_overrun, &p_cuser->buf_overrun))
- ret = -EFAULT;
- ret = 0;
- break;
default:
ret = -ENOIOCTLCMD;
}
- unlock_kernel();
+ mutex_unlock(&info->port.mutex);
return ret;
}

diff --git a/drivers/char/synclinkmp.c b/drivers/char/synclinkmp.c
index 2b18adc..8da976b 100644
--- a/drivers/char/synclinkmp.c
+++ b/drivers/char/synclinkmp.c
@@ -52,7 +52,6 @@
#include <linux/mm.h>
#include <linux/seq_file.h>
#include <linux/slab.h>
-#include <linux/smp_lock.h>
#include <linux/netdevice.h>
#include <linux/vmalloc.h>
#include <linux/init.h>
@@ -1062,9 +1061,7 @@ static void wait_until_sent(struct tty_struct *tty, int timeout)
if (sanity_check(info, tty->name, "wait_until_sent"))
return;

- lock_kernel();
-
- if (!(info->port.flags & ASYNC_INITIALIZED))
+ if (!test_bit(ASYNCB_INITIALIZED, &info->port.flags))
goto exit;

orig_jiffies = jiffies;
@@ -1094,8 +1091,10 @@ static void wait_until_sent(struct tty_struct *tty, int timeout)
break;
}
} else {
- //TODO: determine if there is something similar to USC16C32
- // TXSTATUS_ALL_SENT status
+ /*
+ * TODO: determine if there is something similar to USC16C32
+ * TXSTATUS_ALL_SENT status
+ */
while ( info->tx_active && info->tx_enabled) {
msleep_interruptible(jiffies_to_msecs(char_time));
if (signal_pending(current))
@@ -1106,7 +1105,6 @@ static void wait_until_sent(struct tty_struct *tty, int timeout)
}

exit:
- unlock_kernel();
if (debug_level >= DEBUG_LEVEL_INFO)
printk("%s(%d):%s wait_until_sent() exit\n",
__FILE__,__LINE__, info->device_name );
@@ -1122,7 +1120,6 @@ static int write_room(struct tty_struct *tty)
if (sanity_check(info, tty->name, "write_room"))
return 0;

- lock_kernel();
if (info->params.mode == MGSL_MODE_HDLC) {
ret = (info->tx_active) ? 0 : HDLC_MAX_FRAME_SIZE;
} else {
@@ -1130,7 +1127,6 @@ static int write_room(struct tty_struct *tty)
if (ret < 0)
ret = 0;
}
- unlock_kernel();

if (debug_level >= DEBUG_LEVEL_INFO)
printk("%s(%d):%s write_room()=%d\n",
@@ -1251,7 +1247,7 @@ static void tx_release(struct tty_struct *tty)
*
* Return Value: 0 if success, otherwise error code
*/
-static int do_ioctl(struct tty_struct *tty, struct file *file,
+static int ioctl(struct tty_struct *tty, struct file *file,
unsigned int cmd, unsigned long arg)
{
SLMP_INFO *info = tty->driver_data;
@@ -1341,16 +1337,6 @@ static int do_ioctl(struct tty_struct *tty, struct file *file,
return 0;
}

-static int ioctl(struct tty_struct *tty, struct file *file,
- unsigned int cmd, unsigned long arg)
-{
- int ret;
- lock_kernel();
- ret = do_ioctl(tty, file, cmd, arg);
- unlock_kernel();
- return ret;
-}
-
/*
* /proc fs routines....
*/
@@ -2883,7 +2869,9 @@ static int get_stats(SLMP_INFO * info, struct mgsl_icount __user *user_icount)
if (!user_icount) {
memset(&info->icount, 0, sizeof(info->icount));
} else {
+ mutex_lock(&info->port.mutex);
COPY_TO_USER(err, user_icount, &info->icount, sizeof(struct mgsl_icount));
+ mutex_unlock(&info->port.mutex);
if (err)
return -EFAULT;
}
@@ -2898,7 +2886,9 @@ static int get_params(SLMP_INFO * info, MGSL_PARAMS __user *user_params)
printk("%s(%d):%s get_params()\n",
__FILE__,__LINE__, info->device_name);

+ mutex_lock(&info->port.mutex);
COPY_TO_USER(err,user_params, &info->params, sizeof(MGSL_PARAMS));
+ mutex_unlock(&info->port.mutex);
if (err) {
if ( debug_level >= DEBUG_LEVEL_INFO )
printk( "%s(%d):%s get_params() user buffer copy failed\n",
@@ -2926,11 +2916,13 @@ static int set_params(SLMP_INFO * info, MGSL_PARAMS __user *new_params)
return -EFAULT;
}

+ mutex_lock(&info->port.mutex);
spin_lock_irqsave(&info->lock,flags);
memcpy(&info->params,&tmp_params,sizeof(MGSL_PARAMS));
spin_unlock_irqrestore(&info->lock,flags);

change_params(info);
+ mutex_unlock(&info->port.mutex);

return 0;
}
--
1.7.2

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