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-rw-r--r--drivers/char/synclink.c31
1 files changed, 1 insertions, 30 deletions
diff --git a/drivers/char/synclink.c b/drivers/char/synclink.c
index d68be61f0a49..abb03e52fe12 100644
--- a/drivers/char/synclink.c
+++ b/drivers/char/synclink.c
@@ -941,17 +941,6 @@ static void* mgsl_get_text_ptr(void)
941 return mgsl_get_text_ptr; 941 return mgsl_get_text_ptr;
942} 942}
943 943
944/*
945 * tmp_buf is used as a temporary buffer by mgsl_write. We need to
946 * lock it in case the COPY_FROM_USER blocks while swapping in a page,
947 * and some other program tries to do a serial write at the same time.
948 * Since the lock will only come under contention when the system is
949 * swapping and available memory is low, it makes sense to share one
950 * buffer across all the serial ioports, since it significantly saves
951 * memory if large numbers of serial ports are open.
952 */
953static unsigned char *tmp_buf;
954
955static inline int mgsl_paranoia_check(struct mgsl_struct *info, 944static inline int mgsl_paranoia_check(struct mgsl_struct *info,
956 char *name, const char *routine) 945 char *name, const char *routine)
957{ 946{
@@ -2150,7 +2139,7 @@ static int mgsl_write(struct tty_struct * tty,
2150 if (mgsl_paranoia_check(info, tty->name, "mgsl_write")) 2139 if (mgsl_paranoia_check(info, tty->name, "mgsl_write"))
2151 goto cleanup; 2140 goto cleanup;
2152 2141
2153 if (!tty || !info->xmit_buf || !tmp_buf) 2142 if (!tty || !info->xmit_buf)
2154 goto cleanup; 2143 goto cleanup;
2155 2144
2156 if ( info->params.mode == MGSL_MODE_HDLC || 2145 if ( info->params.mode == MGSL_MODE_HDLC ||
@@ -3438,7 +3427,6 @@ static int mgsl_open(struct tty_struct *tty, struct file * filp)
3438{ 3427{
3439 struct mgsl_struct *info; 3428 struct mgsl_struct *info;
3440 int retval, line; 3429 int retval, line;
3441 unsigned long page;
3442 unsigned long flags; 3430 unsigned long flags;
3443 3431
3444 /* verify range of specified line number */ 3432 /* verify range of specified line number */
@@ -3472,18 +3460,6 @@ static int mgsl_open(struct tty_struct *tty, struct file * filp)
3472 goto cleanup; 3460 goto cleanup;
3473 } 3461 }
3474 3462
3475 if (!tmp_buf) {
3476 page = get_zeroed_page(GFP_KERNEL);
3477 if (!page) {
3478 retval = -ENOMEM;
3479 goto cleanup;
3480 }
3481 if (tmp_buf)
3482 free_page(page);
3483 else
3484 tmp_buf = (unsigned char *) page;
3485 }
3486
3487 info->tty->low_latency = (info->flags & ASYNC_LOW_LATENCY) ? 1 : 0; 3463 info->tty->low_latency = (info->flags & ASYNC_LOW_LATENCY) ? 1 : 0;
3488 3464
3489 spin_lock_irqsave(&info->netlock, flags); 3465 spin_lock_irqsave(&info->netlock, flags);
@@ -4502,11 +4478,6 @@ static void synclink_cleanup(void)
4502 kfree(tmp); 4478 kfree(tmp);
4503 } 4479 }
4504 4480
4505 if (tmp_buf) {
4506 free_page((unsigned long) tmp_buf);
4507 tmp_buf = NULL;
4508 }
4509
4510 if (pci_registered) 4481 if (pci_registered)
4511 pci_unregister_driver(&synclink_pci_driver); 4482 pci_unregister_driver(&synclink_pci_driver);
4512} 4483}