[linux-2.6-block.git] / net / core / hwbm.c

// SPDX-License-Identifier: GPL-2.0-or-later
/* Support for hardware buffer manager.
 *
 * Copyright (C) 2016 Marvell
 *
 * Gregory CLEMENT <gregory.clement@free-electrons.com>
 */
#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)
{
	int err, i;

	mutex_lock(&bm_pool->buf_lock);
	if (bm_pool->buf_num == bm_pool->size) {
		pr_warn("pool already filled\n");
		mutex_unlock(&bm_pool->buf_lock);
		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);
		mutex_unlock(&bm_pool->buf_lock);
		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);
		mutex_unlock(&bm_pool->buf_lock);
		return 0;
	}

	for (i = 0; i < buf_num; i++) {
		err = hwbm_pool_refill(bm_pool, GFP_KERNEL);
		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);
	mutex_unlock(&bm_pool->buf_lock);

	return i;
}
EXPORT_SYMBOL_GPL(hwbm_pool_add);
Commit	Line	Data
2874c5fd	1	// SPDX-License-Identifier: GPL-2.0-or-later
8cb2d8bf GC	2	/* Support for hardware buffer manager.
	3	*
	4	* Copyright (C) 2016 Marvell
	5	*
	6	* Gregory CLEMENT <gregory.clement@free-electrons.com>
8cb2d8bf GC	7	*/
	8	#include <linux/kernel.h>
	9	#include <linux/printk.h>
	10	#include <linux/skbuff.h>
	11	#include <net/hwbm.h>
	12
	13	void hwbm_buf_free(struct hwbm_pool bm_pool, void buf)
	14	{
	15	if (likely(bm_pool->frag_size <= PAGE_SIZE))
	16	skb_free_frag(buf);
	17	else
	18	kfree(buf);
	19	}
	20	EXPORT_SYMBOL_GPL(hwbm_buf_free);
	21
	22	/* Refill processing for HW buffer management */
	23	int hwbm_pool_refill(struct hwbm_pool *bm_pool, gfp_t gfp)
	24	{
	25	int frag_size = bm_pool->frag_size;
	26	void *buf;
	27
	28	if (likely(frag_size <= PAGE_SIZE))
	29	buf = netdev_alloc_frag(frag_size);
	30	else
	31	buf = kmalloc(frag_size, gfp);
	32
	33	if (!buf)
	34	return -ENOMEM;
	35
	36	if (bm_pool->construct)
	37	if (bm_pool->construct(bm_pool, buf)) {
	38	hwbm_buf_free(bm_pool, buf);
	39	return -ENOMEM;
	40	}
	41
	42	return 0;
	43	}
	44	EXPORT_SYMBOL_GPL(hwbm_pool_refill);
	45
6dcdd884	46	int hwbm_pool_add(struct hwbm_pool *bm_pool, unsigned int buf_num)
8cb2d8bf GC	47	{
8cb2d8bf GC	48	int err, i;
8cb2d8bf	49
6dcdd884	50	mutex_lock(&bm_pool->buf_lock);
8cb2d8bf GC	51	if (bm_pool->buf_num == bm_pool->size) {
8cb2d8bf GC	52	pr_warn("pool already filled\n");
6dcdd884	53	mutex_unlock(&bm_pool->buf_lock);
8cb2d8bf GC	54	return bm_pool->buf_num;
	55	}
	56
	57	if (buf_num + bm_pool->buf_num > bm_pool->size) {
	58	pr_warn("cannot allocate %d buffers for pool\n",
	59	buf_num);
6dcdd884	60	mutex_unlock(&bm_pool->buf_lock);
8cb2d8bf GC	61	return 0;
	62	}
	63
	64	if ((buf_num + bm_pool->buf_num) < bm_pool->buf_num) {
	65	pr_warn("Adding %d buffers to the %d current buffers will overflow\n",
	66	buf_num, bm_pool->buf_num);
6dcdd884	67	mutex_unlock(&bm_pool->buf_lock);
8cb2d8bf GC	68	return 0;
	69	}
	70
	71	for (i = 0; i < buf_num; i++) {
6dcdd884	72	err = hwbm_pool_refill(bm_pool, GFP_KERNEL);
8cb2d8bf GC	73	if (err < 0)
	74	break;
	75	}
	76
	77	/* Update BM driver with number of buffers added to pool */
	78	bm_pool->buf_num += i;
	79
	80	pr_debug("hwpm pool: %d of %d buffers added\n", i, buf_num);
6dcdd884	81	mutex_unlock(&bm_pool->buf_lock);
8cb2d8bf GC	82
	83	return i;
	84	}
	85	EXPORT_SYMBOL_GPL(hwbm_pool_add);