1 /* SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause) */ 2 /* 3 * Copyright (c) 2017 Hisilicon Limited. 4 * Copyright (c) 2007, 2008 Mellanox Technologies. All rights reserved. 5 */ 6 7 #include <linux/platform_device.h> 8 #include <rdma/ib_umem.h> 9 #include "hns_roce_device.h" 10 11 int hns_roce_db_map_user(struct hns_roce_ucontext *context, 12 struct ib_udata *udata, unsigned long virt, 13 struct hns_roce_db *db) 14 { 15 unsigned long page_addr = virt & PAGE_MASK; 16 struct hns_roce_user_db_page *page; 17 unsigned int offset; 18 int ret = 0; 19 20 mutex_lock(&context->page_mutex); 21 22 list_for_each_entry(page, &context->page_list, list) 23 if (page->user_virt == page_addr) 24 goto found; 25 26 page = kmalloc(sizeof(*page), GFP_KERNEL); 27 if (!page) { 28 ret = -ENOMEM; 29 goto out; 30 } 31 32 refcount_set(&page->refcount, 1); 33 page->user_virt = page_addr; 34 page->umem = ib_umem_get(context->ibucontext.device, page_addr, 35 PAGE_SIZE, 0); 36 if (IS_ERR(page->umem)) { 37 ret = PTR_ERR(page->umem); 38 kfree(page); 39 goto out; 40 } 41 42 list_add(&page->list, &context->page_list); 43 44 found: 45 offset = virt - page_addr; 46 db->dma = sg_dma_address(page->umem->sg_head.sgl) + offset; 47 db->virt_addr = sg_virt(page->umem->sg_head.sgl) + offset; 48 db->u.user_page = page; 49 refcount_inc(&page->refcount); 50 51 out: 52 mutex_unlock(&context->page_mutex); 53 54 return ret; 55 } 56 57 void hns_roce_db_unmap_user(struct hns_roce_ucontext *context, 58 struct hns_roce_db *db) 59 { 60 mutex_lock(&context->page_mutex); 61 62 refcount_dec(&db->u.user_page->refcount); 63 if (refcount_dec_if_one(&db->u.user_page->refcount)) { 64 list_del(&db->u.user_page->list); 65 ib_umem_release(db->u.user_page->umem); 66 kfree(db->u.user_page); 67 } 68 69 mutex_unlock(&context->page_mutex); 70 } 71 72 static struct hns_roce_db_pgdir *hns_roce_alloc_db_pgdir( 73 struct device *dma_device) 74 { 75 struct hns_roce_db_pgdir *pgdir; 76 77 pgdir = kzalloc(sizeof(*pgdir), GFP_KERNEL); 78 if (!pgdir) 79 return NULL; 80 81 bitmap_fill(pgdir->order1, 82 HNS_ROCE_DB_PER_PAGE / HNS_ROCE_DB_TYPE_COUNT); 83 pgdir->bits[0] = pgdir->order0; 84 pgdir->bits[1] = pgdir->order1; 85 pgdir->page = dma_alloc_coherent(dma_device, PAGE_SIZE, 86 &pgdir->db_dma, GFP_KERNEL); 87 if (!pgdir->page) { 88 kfree(pgdir); 89 return NULL; 90 } 91 92 return pgdir; 93 } 94 95 static int hns_roce_alloc_db_from_pgdir(struct hns_roce_db_pgdir *pgdir, 96 struct hns_roce_db *db, int order) 97 { 98 int o; 99 int i; 100 101 for (o = order; o <= 1; ++o) { 102 i = find_first_bit(pgdir->bits[o], HNS_ROCE_DB_PER_PAGE >> o); 103 if (i < HNS_ROCE_DB_PER_PAGE >> o) 104 goto found; 105 } 106 107 return -ENOMEM; 108 109 found: 110 clear_bit(i, pgdir->bits[o]); 111 112 i <<= o; 113 114 if (o > order) 115 set_bit(i ^ 1, pgdir->bits[order]); 116 117 db->u.pgdir = pgdir; 118 db->index = i; 119 db->db_record = pgdir->page + db->index; 120 db->dma = pgdir->db_dma + db->index * HNS_ROCE_DB_UNIT_SIZE; 121 db->order = order; 122 123 return 0; 124 } 125 126 int hns_roce_alloc_db(struct hns_roce_dev *hr_dev, struct hns_roce_db *db, 127 int order) 128 { 129 struct hns_roce_db_pgdir *pgdir; 130 int ret = 0; 131 132 mutex_lock(&hr_dev->pgdir_mutex); 133 134 list_for_each_entry(pgdir, &hr_dev->pgdir_list, list) 135 if (!hns_roce_alloc_db_from_pgdir(pgdir, db, order)) 136 goto out; 137 138 pgdir = hns_roce_alloc_db_pgdir(hr_dev->dev); 139 if (!pgdir) { 140 ret = -ENOMEM; 141 goto out; 142 } 143 144 list_add(&pgdir->list, &hr_dev->pgdir_list); 145 146 /* This should never fail -- we just allocated an empty page: */ 147 WARN_ON(hns_roce_alloc_db_from_pgdir(pgdir, db, order)); 148 149 out: 150 mutex_unlock(&hr_dev->pgdir_mutex); 151 152 return ret; 153 } 154 155 void hns_roce_free_db(struct hns_roce_dev *hr_dev, struct hns_roce_db *db) 156 { 157 int o; 158 int i; 159 160 mutex_lock(&hr_dev->pgdir_mutex); 161 162 o = db->order; 163 i = db->index; 164 165 if (db->order == 0 && test_bit(i ^ 1, db->u.pgdir->order0)) { 166 clear_bit(i ^ 1, db->u.pgdir->order0); 167 ++o; 168 } 169 170 i >>= o; 171 set_bit(i, db->u.pgdir->bits[o]); 172 173 if (bitmap_full(db->u.pgdir->order1, 174 HNS_ROCE_DB_PER_PAGE / HNS_ROCE_DB_TYPE_COUNT)) { 175 dma_free_coherent(hr_dev->dev, PAGE_SIZE, db->u.pgdir->page, 176 db->u.pgdir->db_dma); 177 list_del(&db->u.pgdir->list); 178 kfree(db->u.pgdir); 179 } 180 181 mutex_unlock(&hr_dev->pgdir_mutex); 182 } 183