1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* Support for hardware buffer manager. 3 * 4 * Copyright (C) 2016 Marvell 5 * 6 * Gregory CLEMENT <gregory.clement@free-electrons.com> 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 46 int hwbm_pool_add(struct hwbm_pool *bm_pool, unsigned int buf_num) 47 { 48 int err, i; 49 50 mutex_lock(&bm_pool->buf_lock); 51 if (bm_pool->buf_num == bm_pool->size) { 52 pr_warn("pool already filled\n"); 53 mutex_unlock(&bm_pool->buf_lock); 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); 60 mutex_unlock(&bm_pool->buf_lock); 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); 67 mutex_unlock(&bm_pool->buf_lock); 68 return 0; 69 } 70 71 for (i = 0; i < buf_num; i++) { 72 err = hwbm_pool_refill(bm_pool, GFP_KERNEL); 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); 81 mutex_unlock(&bm_pool->buf_lock); 82 83 return i; 84 } 85 EXPORT_SYMBOL_GPL(hwbm_pool_add); 86