[PATCH] char: kill unneeded memsets
char, another tmp_buf cleanup
No need to allocate one page as a side buffer. It's no more used. Clean this
(de)allocs of this useless memory pages in char subtree.
Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
Acked-by: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/drivers/char/cyclades.c b/drivers/char/cyclades.c
index f85b4eb..87b2fb5 100644
--- a/drivers/char/cyclades.c
+++ b/drivers/char/cyclades.c
@@ -748,18 +748,6 @@
static int cy_next_channel; /* next minor available */
/*
- * tmp_buf is used as a temporary buffer by serial_write. We need to
- * lock it in case the copy_from_user 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. This buffer is
- * allocated when the first cy_open occurs.
- */
-static unsigned char *tmp_buf;
-
-/*
* This is used to look up the divisor speeds and the timeouts
* We're normally limited to 15 distinct baud rates. The extra
* are accessed via settings in info->flags.
@@ -2466,7 +2454,6 @@
{
struct cyclades_port *info;
int retval, line;
- unsigned long page;
line = tty->index;
if ((line < 0) || (NR_PORTS <= line)){
@@ -2545,15 +2532,6 @@
printk("cyc:cy_open (%d): incrementing count to %d\n",
current->pid, info->count);
#endif
- if (!tmp_buf) {
- page = get_zeroed_page(GFP_KERNEL);
- if (!page)
- return -ENOMEM;
- if (tmp_buf)
- free_page(page);
- else
- tmp_buf = (unsigned char *) page;
- }
/*
* If the port is the middle of closing, bail out now
@@ -2832,7 +2810,7 @@
return 0;
}
- if (!info->xmit_buf || !tmp_buf)
+ if (!info->xmit_buf)
return 0;
CY_LOCK(info, flags);
@@ -5490,10 +5468,6 @@
#endif
}
}
- if (tmp_buf) {
- free_page((unsigned long) tmp_buf);
- tmp_buf = NULL;
- }
} /* cy_cleanup_module */
module_init(cy_init);