diff options
| author | Alan Cox <alan@lxorguk.ukuu.org.uk> | 2006-02-14 17:50:54 +0000 |
|---|---|---|
| committer | Linus Torvalds <torvalds@g5.osdl.org> | 2006-02-14 10:01:39 -0800 |
| commit | 5552c28f6937d2a2b873d06c6d09b96204722dd0 (patch) | |
| tree | 041a8ba94166d9c75c34dc385d5298ae4d59d9fe /drivers/char | |
| parent | 303794400992b907b7cac0d91788603636c7e0fe (diff) | |
[PATCH] Fix locking error in esp
Noted by Al Viro.
Also remove unused tmp_buf
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'drivers/char')
| -rw-r--r-- | drivers/char/esp.c | 22 |
1 files changed, 2 insertions, 20 deletions
diff --git a/drivers/char/esp.c b/drivers/char/esp.c index 57539d8f9f7c..09dc4b01232c 100644 --- a/drivers/char/esp.c +++ b/drivers/char/esp.c @@ -150,17 +150,6 @@ static void rs_wait_until_sent(struct tty_struct *, int); /* Standard COM flags (except for COM4, because of the 8514 problem) */ #define STD_COM_FLAGS (ASYNC_BOOT_AUTOCONF | ASYNC_SKIP_TEST) -/* - * tmp_buf is used as a temporary buffer by serial_write. We need to - * lock it in case the memcpy_fromfs blocks while swapping in a page, - * and some other program tries to do a serial write at the same time. - * Since the lock will only come under contention when the system is - * swapping and available memory is low, it makes sense to share one - * buffer across all the serial ports, since it significantly saves - * memory if large numbers of serial ports are open. - */ -static unsigned char *tmp_buf; - static inline int serial_paranoia_check(struct esp_struct *info, char *name, const char *routine) { @@ -1267,7 +1256,7 @@ static int rs_write(struct tty_struct * tty, if (serial_paranoia_check(info, tty->name, "rs_write")) return 0; - if (!tty || !info->xmit_buf || !tmp_buf) + if (!tty || !info->xmit_buf) return 0; while (1) { @@ -2291,11 +2280,7 @@ static int esp_open(struct tty_struct *tty, struct file * filp) tty->driver_data = info; info->tty = tty; - if (!tmp_buf) { - tmp_buf = (unsigned char *) get_zeroed_page(GFP_KERNEL); - if (!tmp_buf) - return -ENOMEM; - } + spin_unlock_irqrestore(&info->lock, flags); /* * Start up serial port @@ -2602,9 +2587,6 @@ static void __exit espserial_exit(void) free_pages((unsigned long)dma_buffer, get_order(DMA_BUFFER_SZ)); - if (tmp_buf) - free_page((unsigned long)tmp_buf); - while (free_pio_buf) { pio_buf = free_pio_buf->next; kfree(free_pio_buf); |