linux-stable/net/core/hwbm.c
Gregory CLEMENT b388fc7405 net: hwbm: Fix unbalanced spinlock in error case
When hwbm_pool_add exited in error the spinlock was not released. This
patch fixes this issue.

Fixes: 8cb2d8bf57 ("net: add a hardware buffer management helper API")
Reported-by: Jean-Jacques Hiblot <jjhiblot@traphandler.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-05-25 12:35:09 -07:00

90 lines
2.2 KiB
C

/* Support for hardware buffer manager.
*
* Copyright (C) 2016 Marvell
*
* Gregory CLEMENT <gregory.clement@free-electrons.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*/
#include <linux/kernel.h>
#include <linux/printk.h>
#include <linux/skbuff.h>
#include <net/hwbm.h>
void hwbm_buf_free(struct hwbm_pool *bm_pool, void *buf)
{
if (likely(bm_pool->frag_size <= PAGE_SIZE))
skb_free_frag(buf);
else
kfree(buf);
}
EXPORT_SYMBOL_GPL(hwbm_buf_free);
/* Refill processing for HW buffer management */
int hwbm_pool_refill(struct hwbm_pool *bm_pool, gfp_t gfp)
{
int frag_size = bm_pool->frag_size;
void *buf;
if (likely(frag_size <= PAGE_SIZE))
buf = netdev_alloc_frag(frag_size);
else
buf = kmalloc(frag_size, gfp);
if (!buf)
return -ENOMEM;
if (bm_pool->construct)
if (bm_pool->construct(bm_pool, buf)) {
hwbm_buf_free(bm_pool, buf);
return -ENOMEM;
}
return 0;
}
EXPORT_SYMBOL_GPL(hwbm_pool_refill);
int hwbm_pool_add(struct hwbm_pool *bm_pool, unsigned int buf_num, gfp_t gfp)
{
int err, i;
unsigned long flags;
spin_lock_irqsave(&bm_pool->lock, flags);
if (bm_pool->buf_num == bm_pool->size) {
pr_warn("pool already filled\n");
spin_unlock_irqrestore(&bm_pool->lock, flags);
return bm_pool->buf_num;
}
if (buf_num + bm_pool->buf_num > bm_pool->size) {
pr_warn("cannot allocate %d buffers for pool\n",
buf_num);
spin_unlock_irqrestore(&bm_pool->lock, flags);
return 0;
}
if ((buf_num + bm_pool->buf_num) < bm_pool->buf_num) {
pr_warn("Adding %d buffers to the %d current buffers will overflow\n",
buf_num, bm_pool->buf_num);
spin_unlock_irqrestore(&bm_pool->lock, flags);
return 0;
}
for (i = 0; i < buf_num; i++) {
err = hwbm_pool_refill(bm_pool, gfp);
if (err < 0)
break;
}
/* Update BM driver with number of buffers added to pool */
bm_pool->buf_num += i;
pr_debug("hwpm pool: %d of %d buffers added\n", i, buf_num);
spin_unlock_irqrestore(&bm_pool->lock, flags);
return i;
}
EXPORT_SYMBOL_GPL(hwbm_pool_add);