xref: /OK3568_Linux_fs/kernel/net/core/hwbm.c (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyun // SPDX-License-Identifier: GPL-2.0-or-later
2*4882a593Smuzhiyun /* Support for hardware buffer manager.
3*4882a593Smuzhiyun  *
4*4882a593Smuzhiyun  * Copyright (C) 2016 Marvell
5*4882a593Smuzhiyun  *
6*4882a593Smuzhiyun  * Gregory CLEMENT <gregory.clement@free-electrons.com>
7*4882a593Smuzhiyun  */
8*4882a593Smuzhiyun #include <linux/kernel.h>
9*4882a593Smuzhiyun #include <linux/printk.h>
10*4882a593Smuzhiyun #include <linux/skbuff.h>
11*4882a593Smuzhiyun #include <net/hwbm.h>
12*4882a593Smuzhiyun 
hwbm_buf_free(struct hwbm_pool * bm_pool,void * buf)13*4882a593Smuzhiyun void hwbm_buf_free(struct hwbm_pool *bm_pool, void *buf)
14*4882a593Smuzhiyun {
15*4882a593Smuzhiyun 	if (likely(bm_pool->frag_size <= PAGE_SIZE))
16*4882a593Smuzhiyun 		skb_free_frag(buf);
17*4882a593Smuzhiyun 	else
18*4882a593Smuzhiyun 		kfree(buf);
19*4882a593Smuzhiyun }
20*4882a593Smuzhiyun EXPORT_SYMBOL_GPL(hwbm_buf_free);
21*4882a593Smuzhiyun 
22*4882a593Smuzhiyun /* Refill processing for HW buffer management */
hwbm_pool_refill(struct hwbm_pool * bm_pool,gfp_t gfp)23*4882a593Smuzhiyun int hwbm_pool_refill(struct hwbm_pool *bm_pool, gfp_t gfp)
24*4882a593Smuzhiyun {
25*4882a593Smuzhiyun 	int frag_size = bm_pool->frag_size;
26*4882a593Smuzhiyun 	void *buf;
27*4882a593Smuzhiyun 
28*4882a593Smuzhiyun 	if (likely(frag_size <= PAGE_SIZE))
29*4882a593Smuzhiyun 		buf = netdev_alloc_frag(frag_size);
30*4882a593Smuzhiyun 	else
31*4882a593Smuzhiyun 		buf = kmalloc(frag_size, gfp);
32*4882a593Smuzhiyun 
33*4882a593Smuzhiyun 	if (!buf)
34*4882a593Smuzhiyun 		return -ENOMEM;
35*4882a593Smuzhiyun 
36*4882a593Smuzhiyun 	if (bm_pool->construct)
37*4882a593Smuzhiyun 		if (bm_pool->construct(bm_pool, buf)) {
38*4882a593Smuzhiyun 			hwbm_buf_free(bm_pool, buf);
39*4882a593Smuzhiyun 			return -ENOMEM;
40*4882a593Smuzhiyun 		}
41*4882a593Smuzhiyun 
42*4882a593Smuzhiyun 	return 0;
43*4882a593Smuzhiyun }
44*4882a593Smuzhiyun EXPORT_SYMBOL_GPL(hwbm_pool_refill);
45*4882a593Smuzhiyun 
hwbm_pool_add(struct hwbm_pool * bm_pool,unsigned int buf_num)46*4882a593Smuzhiyun int hwbm_pool_add(struct hwbm_pool *bm_pool, unsigned int buf_num)
47*4882a593Smuzhiyun {
48*4882a593Smuzhiyun 	int err, i;
49*4882a593Smuzhiyun 
50*4882a593Smuzhiyun 	mutex_lock(&bm_pool->buf_lock);
51*4882a593Smuzhiyun 	if (bm_pool->buf_num == bm_pool->size) {
52*4882a593Smuzhiyun 		pr_warn("pool already filled\n");
53*4882a593Smuzhiyun 		mutex_unlock(&bm_pool->buf_lock);
54*4882a593Smuzhiyun 		return bm_pool->buf_num;
55*4882a593Smuzhiyun 	}
56*4882a593Smuzhiyun 
57*4882a593Smuzhiyun 	if (buf_num + bm_pool->buf_num > bm_pool->size) {
58*4882a593Smuzhiyun 		pr_warn("cannot allocate %d buffers for pool\n",
59*4882a593Smuzhiyun 			buf_num);
60*4882a593Smuzhiyun 		mutex_unlock(&bm_pool->buf_lock);
61*4882a593Smuzhiyun 		return 0;
62*4882a593Smuzhiyun 	}
63*4882a593Smuzhiyun 
64*4882a593Smuzhiyun 	if ((buf_num + bm_pool->buf_num) < bm_pool->buf_num) {
65*4882a593Smuzhiyun 		pr_warn("Adding %d buffers to the %d current buffers will overflow\n",
66*4882a593Smuzhiyun 			buf_num,  bm_pool->buf_num);
67*4882a593Smuzhiyun 		mutex_unlock(&bm_pool->buf_lock);
68*4882a593Smuzhiyun 		return 0;
69*4882a593Smuzhiyun 	}
70*4882a593Smuzhiyun 
71*4882a593Smuzhiyun 	for (i = 0; i < buf_num; i++) {
72*4882a593Smuzhiyun 		err = hwbm_pool_refill(bm_pool, GFP_KERNEL);
73*4882a593Smuzhiyun 		if (err < 0)
74*4882a593Smuzhiyun 			break;
75*4882a593Smuzhiyun 	}
76*4882a593Smuzhiyun 
77*4882a593Smuzhiyun 	/* Update BM driver with number of buffers added to pool */
78*4882a593Smuzhiyun 	bm_pool->buf_num += i;
79*4882a593Smuzhiyun 
80*4882a593Smuzhiyun 	pr_debug("hwpm pool: %d of %d buffers added\n", i, buf_num);
81*4882a593Smuzhiyun 	mutex_unlock(&bm_pool->buf_lock);
82*4882a593Smuzhiyun 
83*4882a593Smuzhiyun 	return i;
84*4882a593Smuzhiyun }
85*4882a593Smuzhiyun EXPORT_SYMBOL_GPL(hwbm_pool_add);
86