1 /* Support for hardware buffer manager. 2 * 3 * Copyright (C) 2016 Marvell 4 * 5 * Gregory CLEMENT <gregory.clement@free-electrons.com> 6 * 7 * This program is free software; you can redistribute it and/or modify 8 * it under the terms of the GNU General Public License as published by 9 * the Free Software Foundation; either version 2 of the License, or 10 * (at your option) any later version. 11 */ 12 #include <linux/kernel.h> 13 #include <linux/printk.h> 14 #include <linux/skbuff.h> 15 #include <net/hwbm.h> 16 17 void hwbm_buf_free(struct hwbm_pool *bm_pool, void *buf) 18 { 19 if (likely(bm_pool->frag_size <= PAGE_SIZE)) 20 skb_free_frag(buf); 21 else 22 kfree(buf); 23 } 24 EXPORT_SYMBOL_GPL(hwbm_buf_free); 25 26 /* Refill processing for HW buffer management */ 27 int hwbm_pool_refill(struct hwbm_pool *bm_pool, gfp_t gfp) 28 { 29 int frag_size = bm_pool->frag_size; 30 void *buf; 31 32 if (likely(frag_size <= PAGE_SIZE)) 33 buf = netdev_alloc_frag(frag_size); 34 else 35 buf = kmalloc(frag_size, gfp); 36 37 if (!buf) 38 return -ENOMEM; 39 40 if (bm_pool->construct) 41 if (bm_pool->construct(bm_pool, buf)) { 42 hwbm_buf_free(bm_pool, buf); 43 return -ENOMEM; 44 } 45 46 return 0; 47 } 48 EXPORT_SYMBOL_GPL(hwbm_pool_refill); 49 50 int hwbm_pool_add(struct hwbm_pool *bm_pool, unsigned int buf_num, gfp_t gfp) 51 { 52 int err, i; 53 unsigned long flags; 54 55 spin_lock_irqsave(&bm_pool->lock, flags); 56 if (bm_pool->buf_num == bm_pool->size) { 57 pr_warn("pool already filled\n"); 58 return bm_pool->buf_num; 59 } 60 61 if (buf_num + bm_pool->buf_num > bm_pool->size) { 62 pr_warn("cannot allocate %d buffers for pool\n", 63 buf_num); 64 return 0; 65 } 66 67 if ((buf_num + bm_pool->buf_num) < bm_pool->buf_num) { 68 pr_warn("Adding %d buffers to the %d current buffers will overflow\n", 69 buf_num, bm_pool->buf_num); 70 return 0; 71 } 72 73 for (i = 0; i < buf_num; i++) { 74 err = hwbm_pool_refill(bm_pool, gfp); 75 if (err < 0) 76 break; 77 } 78 79 /* Update BM driver with number of buffers added to pool */ 80 bm_pool->buf_num += i; 81 82 pr_debug("hwpm pool: %d of %d buffers added\n", i, buf_num); 83 spin_unlock_irqrestore(&bm_pool->lock, flags); 84 85 return i; 86 } 87 EXPORT_SYMBOL_GPL(hwbm_pool_add); 88