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(udata, page_addr, PAGE_SIZE, 0, 0); 35 if (IS_ERR(page->umem)) { 36 ret = PTR_ERR(page->umem); 37 kfree(page); 38 goto out; 39 } 40 41 list_add(&page->list, &context->page_list); 42 43 found: 44 offset = virt - page_addr; 45 db->dma = sg_dma_address(page->umem->sg_head.sgl) + offset; 46 db->virt_addr = sg_virt(page->umem->sg_head.sgl) + offset; 47 db->u.user_page = page; 48 refcount_inc(&page->refcount); 49 50 out: 51 mutex_unlock(&context->page_mutex); 52 53 return ret; 54 } 55 56 void hns_roce_db_unmap_user(struct hns_roce_ucontext *context, 57 struct hns_roce_db *db) 58 { 59 mutex_lock(&context->page_mutex); 60 61 refcount_dec(&db->u.user_page->refcount); 62 if (refcount_dec_if_one(&db->u.user_page->refcount)) { 63 list_del(&db->u.user_page->list); 64 ib_umem_release(db->u.user_page->umem); 65 kfree(db->u.user_page); 66 } 67 68 mutex_unlock(&context->page_mutex); 69 } 70 71 static struct hns_roce_db_pgdir *hns_roce_alloc_db_pgdir( 72 struct device *dma_device) 73 { 74 struct hns_roce_db_pgdir *pgdir; 75 76 pgdir = kzalloc(sizeof(*pgdir), GFP_KERNEL); 77 if (!pgdir) 78 return NULL; 79 80 bitmap_fill(pgdir->order1, 81 HNS_ROCE_DB_PER_PAGE / HNS_ROCE_DB_TYPE_COUNT); 82 pgdir->bits[0] = pgdir->order0; 83 pgdir->bits[1] = pgdir->order1; 84 pgdir->page = dma_alloc_coherent(dma_device, PAGE_SIZE, 85 &pgdir->db_dma, GFP_KERNEL); 86 if (!pgdir->page) { 87 kfree(pgdir); 88 return NULL; 89 } 90 91 return pgdir; 92 } 93 94 static int hns_roce_alloc_db_from_pgdir(struct hns_roce_db_pgdir *pgdir, 95 struct hns_roce_db *db, int order) 96 { 97 int o; 98 int i; 99 100 for (o = order; o <= 1; ++o) { 101 i = find_first_bit(pgdir->bits[o], HNS_ROCE_DB_PER_PAGE >> o); 102 if (i < HNS_ROCE_DB_PER_PAGE >> o) 103 goto found; 104 } 105 106 return -ENOMEM; 107 108 found: 109 clear_bit(i, pgdir->bits[o]); 110 111 i <<= o; 112 113 if (o > order) 114 set_bit(i ^ 1, pgdir->bits[order]); 115 116 db->u.pgdir = pgdir; 117 db->index = i; 118 db->db_record = pgdir->page + db->index; 119 db->dma = pgdir->db_dma + db->index * HNS_ROCE_DB_UNIT_SIZE; 120 db->order = order; 121 122 return 0; 123 } 124 125 int hns_roce_alloc_db(struct hns_roce_dev *hr_dev, struct hns_roce_db *db, 126 int order) 127 { 128 struct hns_roce_db_pgdir *pgdir; 129 int ret = 0; 130 131 mutex_lock(&hr_dev->pgdir_mutex); 132 133 list_for_each_entry(pgdir, &hr_dev->pgdir_list, list) 134 if (!hns_roce_alloc_db_from_pgdir(pgdir, db, order)) 135 goto out; 136 137 pgdir = hns_roce_alloc_db_pgdir(hr_dev->dev); 138 if (!pgdir) { 139 ret = -ENOMEM; 140 goto out; 141 } 142 143 list_add(&pgdir->list, &hr_dev->pgdir_list); 144 145 /* This should never fail -- we just allocated an empty page: */ 146 WARN_ON(hns_roce_alloc_db_from_pgdir(pgdir, db, order)); 147 148 out: 149 mutex_unlock(&hr_dev->pgdir_mutex); 150 151 return ret; 152 } 153 154 void hns_roce_free_db(struct hns_roce_dev *hr_dev, struct hns_roce_db *db) 155 { 156 int o; 157 int i; 158 159 mutex_lock(&hr_dev->pgdir_mutex); 160 161 o = db->order; 162 i = db->index; 163 164 if (db->order == 0 && test_bit(i ^ 1, db->u.pgdir->order0)) { 165 clear_bit(i ^ 1, db->u.pgdir->order0); 166 ++o; 167 } 168 169 i >>= o; 170 set_bit(i, db->u.pgdir->bits[o]); 171 172 if (bitmap_full(db->u.pgdir->order1, 173 HNS_ROCE_DB_PER_PAGE / HNS_ROCE_DB_TYPE_COUNT)) { 174 dma_free_coherent(hr_dev->dev, PAGE_SIZE, db->u.pgdir->page, 175 db->u.pgdir->db_dma); 176 list_del(&db->u.pgdir->list); 177 kfree(db->u.pgdir); 178 } 179 180 mutex_unlock(&hr_dev->pgdir_mutex); 181 } 182