1 /*
2  * ISHTP Ring Buffers
3  *
4  * Copyright (c) 2003-2016, Intel Corporation.
5  *
6  * This program is free software; you can redistribute it and/or modify it
7  * under the terms and conditions of the GNU General Public License,
8  * version 2, as published by the Free Software Foundation.
9  *
10  * This program is distributed in the hope it will be useful, but WITHOUT
11  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12  * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
13  * more details.
14  *
15  */
16 
17 #include <linux/slab.h>
18 #include "client.h"
19 
20 /**
21  * ishtp_cl_alloc_rx_ring() - Allocate RX ring buffers
22  * @cl: client device instance
23  *
24  * Allocate and initialize RX ring buffers
25  *
26  * Return: 0 on success else -ENOMEM
27  */
ishtp_cl_alloc_rx_ring(struct ishtp_cl * cl)28 int ishtp_cl_alloc_rx_ring(struct ishtp_cl *cl)
29 {
30 	size_t	len = cl->device->fw_client->props.max_msg_length;
31 	int	j;
32 	struct ishtp_cl_rb *rb;
33 	int	ret = 0;
34 	unsigned long	flags;
35 
36 	for (j = 0; j < cl->rx_ring_size; ++j) {
37 		rb = ishtp_io_rb_init(cl);
38 		if (!rb) {
39 			ret = -ENOMEM;
40 			goto out;
41 		}
42 		ret = ishtp_io_rb_alloc_buf(rb, len);
43 		if (ret)
44 			goto out;
45 		spin_lock_irqsave(&cl->free_list_spinlock, flags);
46 		list_add_tail(&rb->list, &cl->free_rb_list.list);
47 		spin_unlock_irqrestore(&cl->free_list_spinlock, flags);
48 	}
49 
50 	return	0;
51 
52 out:
53 	dev_err(&cl->device->dev, "error in allocating Rx buffers\n");
54 	ishtp_cl_free_rx_ring(cl);
55 	return	ret;
56 }
57 
58 /**
59  * ishtp_cl_alloc_tx_ring() - Allocate TX ring buffers
60  * @cl: client device instance
61  *
62  * Allocate and initialize TX ring buffers
63  *
64  * Return: 0 on success else -ENOMEM
65  */
ishtp_cl_alloc_tx_ring(struct ishtp_cl * cl)66 int ishtp_cl_alloc_tx_ring(struct ishtp_cl *cl)
67 {
68 	size_t	len = cl->device->fw_client->props.max_msg_length;
69 	int	j;
70 	unsigned long	flags;
71 
72 	/* Allocate pool to free Tx bufs */
73 	for (j = 0; j < cl->tx_ring_size; ++j) {
74 		struct ishtp_cl_tx_ring	*tx_buf;
75 
76 		tx_buf = kzalloc(sizeof(struct ishtp_cl_tx_ring), GFP_KERNEL);
77 		if (!tx_buf)
78 			goto	out;
79 
80 		tx_buf->send_buf.data = kmalloc(len, GFP_KERNEL);
81 		if (!tx_buf->send_buf.data) {
82 			kfree(tx_buf);
83 			goto	out;
84 		}
85 
86 		spin_lock_irqsave(&cl->tx_free_list_spinlock, flags);
87 		list_add_tail(&tx_buf->list, &cl->tx_free_list.list);
88 		spin_unlock_irqrestore(&cl->tx_free_list_spinlock, flags);
89 	}
90 	return	0;
91 out:
92 	dev_err(&cl->device->dev, "error in allocating Tx pool\n");
93 	ishtp_cl_free_tx_ring(cl);
94 	return	-ENOMEM;
95 }
96 
97 /**
98  * ishtp_cl_free_rx_ring() - Free RX ring buffers
99  * @cl: client device instance
100  *
101  * Free RX ring buffers
102  */
ishtp_cl_free_rx_ring(struct ishtp_cl * cl)103 void ishtp_cl_free_rx_ring(struct ishtp_cl *cl)
104 {
105 	struct ishtp_cl_rb *rb;
106 	unsigned long	flags;
107 
108 	/* release allocated memory - pass over free_rb_list */
109 	spin_lock_irqsave(&cl->free_list_spinlock, flags);
110 	while (!list_empty(&cl->free_rb_list.list)) {
111 		rb = list_entry(cl->free_rb_list.list.next, struct ishtp_cl_rb,
112 				list);
113 		list_del(&rb->list);
114 		kfree(rb->buffer.data);
115 		kfree(rb);
116 	}
117 	spin_unlock_irqrestore(&cl->free_list_spinlock, flags);
118 	/* release allocated memory - pass over in_process_list */
119 	spin_lock_irqsave(&cl->in_process_spinlock, flags);
120 	while (!list_empty(&cl->in_process_list.list)) {
121 		rb = list_entry(cl->in_process_list.list.next,
122 				struct ishtp_cl_rb, list);
123 		list_del(&rb->list);
124 		kfree(rb->buffer.data);
125 		kfree(rb);
126 	}
127 	spin_unlock_irqrestore(&cl->in_process_spinlock, flags);
128 }
129 
130 /**
131  * ishtp_cl_free_tx_ring() - Free TX ring buffers
132  * @cl: client device instance
133  *
134  * Free TX ring buffers
135  */
ishtp_cl_free_tx_ring(struct ishtp_cl * cl)136 void ishtp_cl_free_tx_ring(struct ishtp_cl *cl)
137 {
138 	struct ishtp_cl_tx_ring	*tx_buf;
139 	unsigned long	flags;
140 
141 	spin_lock_irqsave(&cl->tx_free_list_spinlock, flags);
142 	/* release allocated memory - pass over tx_free_list */
143 	while (!list_empty(&cl->tx_free_list.list)) {
144 		tx_buf = list_entry(cl->tx_free_list.list.next,
145 				    struct ishtp_cl_tx_ring, list);
146 		list_del(&tx_buf->list);
147 		kfree(tx_buf->send_buf.data);
148 		kfree(tx_buf);
149 	}
150 	spin_unlock_irqrestore(&cl->tx_free_list_spinlock, flags);
151 
152 	spin_lock_irqsave(&cl->tx_list_spinlock, flags);
153 	/* release allocated memory - pass over tx_list */
154 	while (!list_empty(&cl->tx_list.list)) {
155 		tx_buf = list_entry(cl->tx_list.list.next,
156 				    struct ishtp_cl_tx_ring, list);
157 		list_del(&tx_buf->list);
158 		kfree(tx_buf->send_buf.data);
159 		kfree(tx_buf);
160 	}
161 	spin_unlock_irqrestore(&cl->tx_list_spinlock, flags);
162 }
163 
164 /**
165  * ishtp_io_rb_free() - Free IO request block
166  * @rb: IO request block
167  *
168  * Free io request block memory
169  */
ishtp_io_rb_free(struct ishtp_cl_rb * rb)170 void ishtp_io_rb_free(struct ishtp_cl_rb *rb)
171 {
172 	if (rb == NULL)
173 		return;
174 
175 	kfree(rb->buffer.data);
176 	kfree(rb);
177 }
178 
179 /**
180  * ishtp_io_rb_init() - Allocate and init IO request block
181  * @cl: client device instance
182  *
183  * Allocate and initialize request block
184  *
185  * Return: Allocted IO request block pointer
186  */
ishtp_io_rb_init(struct ishtp_cl * cl)187 struct ishtp_cl_rb *ishtp_io_rb_init(struct ishtp_cl *cl)
188 {
189 	struct ishtp_cl_rb *rb;
190 
191 	rb = kzalloc(sizeof(struct ishtp_cl_rb), GFP_KERNEL);
192 	if (!rb)
193 		return NULL;
194 
195 	INIT_LIST_HEAD(&rb->list);
196 	rb->cl = cl;
197 	rb->buf_idx = 0;
198 	return rb;
199 }
200 
201 /**
202  * ishtp_io_rb_alloc_buf() - Allocate and init response buffer
203  * @rb: IO request block
204  * @length: length of response buffer
205  *
206  * Allocate respose buffer
207  *
208  * Return: 0 on success else -ENOMEM
209  */
ishtp_io_rb_alloc_buf(struct ishtp_cl_rb * rb,size_t length)210 int ishtp_io_rb_alloc_buf(struct ishtp_cl_rb *rb, size_t length)
211 {
212 	if (!rb)
213 		return -EINVAL;
214 
215 	if (length == 0)
216 		return 0;
217 
218 	rb->buffer.data = kmalloc(length, GFP_KERNEL);
219 	if (!rb->buffer.data)
220 		return -ENOMEM;
221 
222 	rb->buffer.size = length;
223 	return 0;
224 }
225 
226 /**
227  * ishtp_cl_io_rb_recycle() - Recycle IO request blocks
228  * @rb: IO request block
229  *
230  * Re-append rb to its client's free list and send flow control if needed
231  *
232  * Return: 0 on success else -EFAULT
233  */
ishtp_cl_io_rb_recycle(struct ishtp_cl_rb * rb)234 int ishtp_cl_io_rb_recycle(struct ishtp_cl_rb *rb)
235 {
236 	struct ishtp_cl *cl;
237 	int	rets = 0;
238 	unsigned long	flags;
239 
240 	if (!rb || !rb->cl)
241 		return	-EFAULT;
242 
243 	cl = rb->cl;
244 	spin_lock_irqsave(&cl->free_list_spinlock, flags);
245 	list_add_tail(&rb->list, &cl->free_rb_list.list);
246 	spin_unlock_irqrestore(&cl->free_list_spinlock, flags);
247 
248 	/*
249 	 * If we returned the first buffer to empty 'free' list,
250 	 * send flow control
251 	 */
252 	if (!cl->out_flow_ctrl_creds)
253 		rets = ishtp_cl_read_start(cl);
254 
255 	return	rets;
256 }
257 EXPORT_SYMBOL(ishtp_cl_io_rb_recycle);
258