blob: eb17e0a3ac61e4a0ff702b2edf8ebf894cb35c0f [file] [log] [blame]
Jack Steinerb2fb06fc2008-07-29 22:33:56 -07001
2/*
3 * Copyright (c) 2008 Silicon Graphics, Inc. All Rights Reserved.
4 *
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation; either version 2 of the License, or
8 * (at your option) any later version.
9 *
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
14 *
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, write to the Free Software
17 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
18 */
19#ifndef __GRU_KSERVICES_H_
20#define __GRU_KSERVICES_H_
21
22
23/*
24 * Message queues using the GRU to send/receive messages.
25 *
26 * These function allow the user to create a message queue for
27 * sending/receiving 1 or 2 cacheline messages using the GRU.
28 *
29 * Processes SENDING messages will use a kernel CBR/DSR to send
30 * the message. This is transparent to the caller.
31 *
32 * The receiver does not use any GRU resources.
33 *
34 * The functions support:
35 * - single receiver
36 * - multiple senders
37 * - cross partition message
38 *
39 * Missing features ZZZ:
40 * - user options for dealing with timeouts, queue full, etc.
41 * - gru_create_message_queue() needs interrupt vector info
42 */
43
44/*
45 * Initialize a user allocated chunk of memory to be used as
46 * a message queue. The caller must ensure that the queue is
47 * in contiguous physical memory and is cacheline aligned.
48 *
49 * Message queue size is the total number of bytes allocated
50 * to the queue including a 2 cacheline header that is used
51 * to manage the queue.
52 *
53 * Input:
54 * p pointer to user allocated memory.
55 * bytes size of message queue in bytes
56 *
57 * Errors:
58 * 0 OK
59 * >0 error
60 */
61extern int gru_create_message_queue(void *p, unsigned int bytes);
62
63/*
64 * Send a message to a message queue.
65 *
66 * Note: The message queue transport mechanism uses the first 32
67 * bits of the message. Users should avoid using these bits.
68 *
69 *
70 * Input:
71 * xmq message queue - must be a UV global physical address
72 * mesg pointer to message. Must be 64-bit aligned
73 * bytes size of message in bytes
74 *
75 * Output:
76 * 0 message sent
77 * >0 Send failure - see error codes below
78 *
79 */
80extern int gru_send_message_gpa(unsigned long mq_gpa, void *mesg,
81 unsigned int bytes);
82
83/* Status values for gru_send_message() */
84#define MQE_OK 0 /* message sent successfully */
85#define MQE_CONGESTION 1 /* temporary congestion, try again */
86#define MQE_QUEUE_FULL 2 /* queue is full */
87#define MQE_UNEXPECTED_CB_ERR 3 /* unexpected CB error */
88#define MQE_PAGE_OVERFLOW 10 /* BUG - queue overflowed a page */
89#define MQE_BUG_NO_RESOURCES 11 /* BUG - could not alloc GRU cb/dsr */
90
91/*
92 * Advance the receive pointer for the message queue to the next message.
93 * Note: current API requires messages to be gotten & freed in order. Future
94 * API extensions may allow for out-of-order freeing.
95 *
96 * Input
97 * mq message queue
98 * mesq message being freed
99 */
100extern void gru_free_message(void *mq, void *mesq);
101
102/*
103 * Get next message from message queue. Returns pointer to
104 * message OR NULL if no message present.
105 * User must call gru_free_message() after message is processed
106 * in order to move the queue pointers to next message.
107 *
108 * Input
109 * mq message queue
110 *
111 * Output:
112 * p pointer to message
113 * NULL no message available
114 */
115extern void *gru_get_next_message(void *mq);
116
117
118/*
119 * Copy data using the GRU. Source or destination can be located in a remote
120 * partition.
121 *
122 * Input:
123 * dest_gpa destination global physical address
124 * src_gpa source global physical address
125 * bytes number of bytes to copy
126 *
127 * Output:
128 * 0 OK
129 * >0 error
130 */
131extern int gru_copy_gpa(unsigned long dest_gpa, unsigned long src_gpa,
132 unsigned int bytes);
133
134#endif /* __GRU_KSERVICES_H_ */