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 return NULL; 65 66 q = kzalloc(sizeof(*q), GFP_KERNEL); 67 if (!q) 68 return NULL; 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 return NULL; 104 } 105 106 /* copies elements from original q to new q and then swaps the contents of the 107 * two q headers. This is so that if anyone is holding a pointer to q it will 108 * still work 109 */ 110 static int resize_finish(struct rxe_queue *q, struct rxe_queue *new_q, 111 unsigned int num_elem) 112 { 113 enum queue_type type = q->type; 114 u32 new_prod; 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 new_prod = queue_get_producer(new_q, type); 122 prod = queue_get_producer(q, type); 123 cons = queue_get_consumer(q, type); 124 125 while ((prod - cons) & q->index_mask) { 126 memcpy(queue_addr_from_index(new_q, new_prod), 127 queue_addr_from_index(q, cons), new_q->elem_size); 128 new_prod = queue_next_index(new_q, new_prod); 129 cons = queue_next_index(q, cons); 130 } 131 132 new_q->buf->producer_index = new_prod; 133 q->buf->consumer_index = cons; 134 135 /* update private index copies */ 136 if (type == QUEUE_TYPE_TO_CLIENT) 137 new_q->index = new_q->buf->producer_index; 138 else 139 q->index = q->buf->consumer_index; 140 141 /* exchange rxe_queue headers */ 142 swap(*q, *new_q); 143 144 return 0; 145 } 146 147 int rxe_queue_resize(struct rxe_queue *q, unsigned int *num_elem_p, 148 unsigned int elem_size, struct ib_udata *udata, 149 struct mminfo __user *outbuf, spinlock_t *producer_lock, 150 spinlock_t *consumer_lock) 151 { 152 struct rxe_queue *new_q; 153 unsigned int num_elem = *num_elem_p; 154 int err; 155 unsigned long producer_flags; 156 unsigned long consumer_flags; 157 158 new_q = rxe_queue_init(q->rxe, &num_elem, elem_size, q->type); 159 if (!new_q) 160 return -ENOMEM; 161 162 err = do_mmap_info(new_q->rxe, outbuf, udata, new_q->buf, 163 new_q->buf_size, &new_q->ip); 164 if (err) { 165 vfree(new_q->buf); 166 kfree(new_q); 167 goto err1; 168 } 169 170 spin_lock_irqsave(consumer_lock, consumer_flags); 171 172 if (producer_lock) { 173 spin_lock_irqsave(producer_lock, producer_flags); 174 err = resize_finish(q, new_q, num_elem); 175 spin_unlock_irqrestore(producer_lock, producer_flags); 176 } else { 177 err = resize_finish(q, new_q, num_elem); 178 } 179 180 spin_unlock_irqrestore(consumer_lock, consumer_flags); 181 182 rxe_queue_cleanup(new_q); /* new/old dep on err */ 183 if (err) 184 goto err1; 185 186 *num_elem_p = num_elem; 187 return 0; 188 189 err1: 190 return err; 191 } 192 193 void rxe_queue_cleanup(struct rxe_queue *q) 194 { 195 if (q->ip) 196 kref_put(&q->ip->ref, rxe_mmap_release); 197 else 198 vfree(q->buf); 199 200 kfree(q); 201 } 202