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1// SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB2/*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 12int 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 40err2:41	kfree(ip);42err1:43	return err;44}45 46inline void rxe_queue_reset(struct rxe_queue *q)47{48	/* queue is comprised from header and the memory49	 * of the actual queue. See "struct rxe_queue_buf" in rxe_queue.h50	 * reset only the queue itself and not the management header51	 */52	memset(q->buf->data, 0, q->buf_size - sizeof(struct rxe_queue_buf));53}54 55struct 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 101err2:102	kfree(q);103	return NULL;104}105 106/* copies elements from original q to new q and then swaps the contents of the107 * two q headers. This is so that if anyone is holding a pointer to q it will108 * still work109 */110static 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	else139		q->index = q->buf->consumer_index;140 141	/* exchange rxe_queue headers */142	swap(*q, *new_q);143 144	return 0;145}146 147int 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 189err1:190	return err;191}192 193void rxe_queue_cleanup(struct rxe_queue *q)194{195	if (q->ip)196		kref_put(&q->ip->ref, rxe_mmap_release);197	else198		vfree(q->buf);199 200	kfree(q);201}202