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 if (!queue_empty(q, q->type) && (num_elem < queue_count(q, q->type))) 115 return -EINVAL; 116 117 while (!queue_empty(q, q->type)) { 118 memcpy(producer_addr(new_q, new_q->type), 119 consumer_addr(q, q->type), 120 new_q->elem_size); 121 advance_producer(new_q, new_q->type); 122 advance_consumer(q, q->type); 123 } 124 125 swap(*q, *new_q); 126 127 return 0; 128 } 129 130 int rxe_queue_resize(struct rxe_queue *q, unsigned int *num_elem_p, 131 unsigned int elem_size, struct ib_udata *udata, 132 struct mminfo __user *outbuf, spinlock_t *producer_lock, 133 spinlock_t *consumer_lock) 134 { 135 struct rxe_queue *new_q; 136 unsigned int num_elem = *num_elem_p; 137 int err; 138 unsigned long flags = 0, flags1; 139 140 new_q = rxe_queue_init(q->rxe, &num_elem, elem_size, q->type); 141 if (!new_q) 142 return -ENOMEM; 143 144 err = do_mmap_info(new_q->rxe, outbuf, udata, new_q->buf, 145 new_q->buf_size, &new_q->ip); 146 if (err) { 147 vfree(new_q->buf); 148 kfree(new_q); 149 goto err1; 150 } 151 152 spin_lock_irqsave(consumer_lock, flags1); 153 154 if (producer_lock) { 155 spin_lock_irqsave(producer_lock, flags); 156 err = resize_finish(q, new_q, num_elem); 157 spin_unlock_irqrestore(producer_lock, flags); 158 } else { 159 err = resize_finish(q, new_q, num_elem); 160 } 161 162 spin_unlock_irqrestore(consumer_lock, flags1); 163 164 rxe_queue_cleanup(new_q); /* new/old dep on err */ 165 if (err) 166 goto err1; 167 168 *num_elem_p = num_elem; 169 return 0; 170 171 err1: 172 return err; 173 } 174 175 void rxe_queue_cleanup(struct rxe_queue *q) 176 { 177 if (q->ip) 178 kref_put(&q->ip->ref, rxe_mmap_release); 179 else 180 vfree(q->buf); 181 182 kfree(q); 183 } 184