1 // SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB 2 /* 3 * Copyright (c) 2016 Mellanox Technologies Ltd. All rights reserved. 4 * Copyright (c) 2015 System Fabric Works, Inc. All rights reserved. 5 */ 6 7 #include <linux/vmalloc.h> 8 #include "rxe.h" 9 #include "rxe_loc.h" 10 #include "rxe_queue.h" 11 12 int do_mmap_info(struct rxe_dev *rxe, struct mminfo __user *outbuf, 13 struct ib_udata *udata, struct rxe_queue_buf *buf, 14 size_t buf_size, struct rxe_mmap_info **ip_p) 15 { 16 int err; 17 struct rxe_mmap_info *ip = NULL; 18 19 if (outbuf) { 20 ip = rxe_create_mmap_info(rxe, buf_size, udata, buf); 21 if (IS_ERR(ip)) { 22 err = PTR_ERR(ip); 23 goto err1; 24 } 25 26 if (copy_to_user(outbuf, &ip->info, sizeof(ip->info))) { 27 err = -EFAULT; 28 goto err2; 29 } 30 31 spin_lock_bh(&rxe->pending_lock); 32 list_add(&ip->pending_mmaps, &rxe->pending_mmaps); 33 spin_unlock_bh(&rxe->pending_lock); 34 } 35 36 *ip_p = ip; 37 38 return 0; 39 40 err2: 41 kfree(ip); 42 err1: 43 return err; 44 } 45 46 inline void rxe_queue_reset(struct rxe_queue *q) 47 { 48 /* queue is comprised from header and the memory 49 * of the actual queue. See "struct rxe_queue_buf" in rxe_queue.h 50 * reset only the queue itself and not the management header 51 */ 52 memset(q->buf->data, 0, q->buf_size - sizeof(struct rxe_queue_buf)); 53 } 54 55 struct rxe_queue *rxe_queue_init(struct rxe_dev *rxe, int *num_elem, 56 unsigned int elem_size, enum queue_type type) 57 { 58 struct rxe_queue *q; 59 size_t buf_size; 60 unsigned int num_slots; 61 62 /* num_elem == 0 is allowed, but uninteresting */ 63 if (*num_elem < 0) 64 goto err1; 65 66 q = kzalloc(sizeof(*q), GFP_KERNEL); 67 if (!q) 68 goto err1; 69 70 q->rxe = rxe; 71 q->type = type; 72 73 /* used in resize, only need to copy used part of queue */ 74 q->elem_size = elem_size; 75 76 /* pad element up to at least a cacheline and always a power of 2 */ 77 if (elem_size < cache_line_size()) 78 elem_size = cache_line_size(); 79 elem_size = roundup_pow_of_two(elem_size); 80 81 q->log2_elem_size = order_base_2(elem_size); 82 83 num_slots = *num_elem + 1; 84 num_slots = roundup_pow_of_two(num_slots); 85 q->index_mask = num_slots - 1; 86 87 buf_size = sizeof(struct rxe_queue_buf) + num_slots * elem_size; 88 89 q->buf = vmalloc_user(buf_size); 90 if (!q->buf) 91 goto err2; 92 93 q->buf->log2_elem_size = q->log2_elem_size; 94 q->buf->index_mask = q->index_mask; 95 96 q->buf_size = buf_size; 97 98 *num_elem = num_slots - 1; 99 return q; 100 101 err2: 102 kfree(q); 103 err1: 104 return NULL; 105 } 106 107 /* copies elements from original q to new q and then swaps the contents of the 108 * two q headers. This is so that if anyone is holding a pointer to q it will 109 * still work 110 */ 111 static int resize_finish(struct rxe_queue *q, struct rxe_queue *new_q, 112 unsigned int num_elem) 113 { 114 enum queue_type type = q->type; 115 u32 prod; 116 u32 cons; 117 118 if (!queue_empty(q, q->type) && (num_elem < queue_count(q, type))) 119 return -EINVAL; 120 121 prod = queue_get_producer(new_q, type); 122 cons = queue_get_consumer(q, type); 123 124 while (!queue_empty(q, type)) { 125 memcpy(queue_addr_from_index(new_q, prod), 126 queue_addr_from_index(q, cons), new_q->elem_size); 127 prod = queue_next_index(new_q, prod); 128 cons = queue_next_index(q, cons); 129 } 130 131 new_q->buf->producer_index = prod; 132 q->buf->consumer_index = cons; 133 134 /* update private index copies */ 135 if (type == QUEUE_TYPE_TO_CLIENT) 136 new_q->index = new_q->buf->producer_index; 137 else 138 q->index = q->buf->consumer_index; 139 140 /* exchange rxe_queue headers */ 141 swap(*q, *new_q); 142 143 return 0; 144 } 145 146 int rxe_queue_resize(struct rxe_queue *q, unsigned int *num_elem_p, 147 unsigned int elem_size, struct ib_udata *udata, 148 struct mminfo __user *outbuf, spinlock_t *producer_lock, 149 spinlock_t *consumer_lock) 150 { 151 struct rxe_queue *new_q; 152 unsigned int num_elem = *num_elem_p; 153 int err; 154 155 new_q = rxe_queue_init(q->rxe, &num_elem, elem_size, q->type); 156 if (!new_q) 157 return -ENOMEM; 158 159 err = do_mmap_info(new_q->rxe, outbuf, udata, new_q->buf, 160 new_q->buf_size, &new_q->ip); 161 if (err) { 162 vfree(new_q->buf); 163 kfree(new_q); 164 goto err1; 165 } 166 167 spin_lock_bh(consumer_lock); 168 169 if (producer_lock) { 170 spin_lock_bh(producer_lock); 171 err = resize_finish(q, new_q, num_elem); 172 spin_unlock_bh(producer_lock); 173 } else { 174 err = resize_finish(q, new_q, num_elem); 175 } 176 177 spin_unlock_bh(consumer_lock); 178 179 rxe_queue_cleanup(new_q); /* new/old dep on err */ 180 if (err) 181 goto err1; 182 183 *num_elem_p = num_elem; 184 return 0; 185 186 err1: 187 return err; 188 } 189 190 void rxe_queue_cleanup(struct rxe_queue *q) 191 { 192 if (q->ip) 193 kref_put(&q->ip->ref, rxe_mmap_release); 194 else 195 vfree(q->buf); 196 197 kfree(q); 198 } 199