1 | /* |
2 | * This file is subject to the terms and conditions of the GNU General Public |
3 | * License. See the file "COPYING" in the main directory of this archive |
4 | * for more details. |
5 | * |
6 | * (C) Copyright 2020 Hewlett Packard Enterprise Development LP |
7 | * Copyright (c) 2004-2008 Silicon Graphics, Inc. All Rights Reserved. |
8 | */ |
9 | |
10 | /* |
11 | * Cross Partition (XP) base. |
12 | * |
13 | * XP provides a base from which its users can interact |
14 | * with XPC, yet not be dependent on XPC. |
15 | * |
16 | */ |
17 | |
18 | #include <linux/module.h> |
19 | #include <linux/device.h> |
20 | #include "xp.h" |
21 | |
22 | /* define the XP debug device structures to be used with dev_dbg() et al */ |
23 | |
24 | static struct device_driver xp_dbg_name = { |
25 | .name = "xp" |
26 | }; |
27 | |
28 | static struct device xp_dbg_subname = { |
29 | .init_name = "" , /* set to "" */ |
30 | .driver = &xp_dbg_name |
31 | }; |
32 | |
33 | struct device *xp = &xp_dbg_subname; |
34 | |
35 | /* max #of partitions possible */ |
36 | short xp_max_npartitions; |
37 | EXPORT_SYMBOL_GPL(xp_max_npartitions); |
38 | |
39 | short xp_partition_id; |
40 | EXPORT_SYMBOL_GPL(xp_partition_id); |
41 | |
42 | u8 xp_region_size; |
43 | EXPORT_SYMBOL_GPL(xp_region_size); |
44 | |
45 | unsigned long (*xp_pa) (void *addr); |
46 | EXPORT_SYMBOL_GPL(xp_pa); |
47 | |
48 | unsigned long (*xp_socket_pa) (unsigned long gpa); |
49 | EXPORT_SYMBOL_GPL(xp_socket_pa); |
50 | |
51 | enum xp_retval (*xp_remote_memcpy) (unsigned long dst_gpa, |
52 | const unsigned long src_gpa, size_t len); |
53 | EXPORT_SYMBOL_GPL(xp_remote_memcpy); |
54 | |
55 | int (*xp_cpu_to_nasid) (int cpuid); |
56 | EXPORT_SYMBOL_GPL(xp_cpu_to_nasid); |
57 | |
58 | enum xp_retval (*xp_expand_memprotect) (unsigned long phys_addr, |
59 | unsigned long size); |
60 | EXPORT_SYMBOL_GPL(xp_expand_memprotect); |
61 | enum xp_retval (*xp_restrict_memprotect) (unsigned long phys_addr, |
62 | unsigned long size); |
63 | EXPORT_SYMBOL_GPL(xp_restrict_memprotect); |
64 | |
65 | /* |
66 | * xpc_registrations[] keeps track of xpc_connect()'s done by the kernel-level |
67 | * users of XPC. |
68 | */ |
69 | struct xpc_registration xpc_registrations[XPC_MAX_NCHANNELS]; |
70 | EXPORT_SYMBOL_GPL(xpc_registrations); |
71 | |
72 | /* |
73 | * Initialize the XPC interface to NULL to indicate that XPC isn't loaded. |
74 | */ |
75 | struct xpc_interface xpc_interface = { }; |
76 | EXPORT_SYMBOL_GPL(xpc_interface); |
77 | |
78 | /* |
79 | * XPC calls this when it (the XPC module) has been loaded. |
80 | */ |
81 | void |
82 | xpc_set_interface(void (*connect) (int), |
83 | void (*disconnect) (int), |
84 | enum xp_retval (*send) (short, int, u32, void *, u16), |
85 | enum xp_retval (*send_notify) (short, int, u32, void *, u16, |
86 | xpc_notify_func, void *), |
87 | void (*received) (short, int, void *), |
88 | enum xp_retval (*partid_to_nasids) (short, void *)) |
89 | { |
90 | xpc_interface.connect = connect; |
91 | xpc_interface.disconnect = disconnect; |
92 | xpc_interface.send = send; |
93 | xpc_interface.send_notify = send_notify; |
94 | xpc_interface.received = received; |
95 | xpc_interface.partid_to_nasids = partid_to_nasids; |
96 | } |
97 | EXPORT_SYMBOL_GPL(xpc_set_interface); |
98 | |
99 | /* |
100 | * XPC calls this when it (the XPC module) is being unloaded. |
101 | */ |
102 | void |
103 | xpc_clear_interface(void) |
104 | { |
105 | memset(&xpc_interface, 0, sizeof(xpc_interface)); |
106 | } |
107 | EXPORT_SYMBOL_GPL(xpc_clear_interface); |
108 | |
109 | /* |
110 | * Register for automatic establishment of a channel connection whenever |
111 | * a partition comes up. |
112 | * |
113 | * Arguments: |
114 | * |
115 | * ch_number - channel # to register for connection. |
116 | * func - function to call for asynchronous notification of channel |
117 | * state changes (i.e., connection, disconnection, error) and |
118 | * the arrival of incoming messages. |
119 | * key - pointer to optional user-defined value that gets passed back |
120 | * to the user on any callouts made to func. |
121 | * payload_size - size in bytes of the XPC message's payload area which |
122 | * contains a user-defined message. The user should make |
123 | * this large enough to hold their largest message. |
124 | * nentries - max #of XPC message entries a message queue can contain. |
125 | * The actual number, which is determined when a connection |
126 | * is established and may be less then requested, will be |
127 | * passed to the user via the xpConnected callout. |
128 | * assigned_limit - max number of kthreads allowed to be processing |
129 | * messages (per connection) at any given instant. |
130 | * idle_limit - max number of kthreads allowed to be idle at any given |
131 | * instant. |
132 | */ |
133 | enum xp_retval |
134 | xpc_connect(int ch_number, xpc_channel_func func, void *key, u16 payload_size, |
135 | u16 nentries, u32 assigned_limit, u32 idle_limit) |
136 | { |
137 | struct xpc_registration *registration; |
138 | |
139 | DBUG_ON(ch_number < 0 || ch_number >= XPC_MAX_NCHANNELS); |
140 | DBUG_ON(payload_size == 0 || nentries == 0); |
141 | DBUG_ON(func == NULL); |
142 | DBUG_ON(assigned_limit == 0 || idle_limit > assigned_limit); |
143 | |
144 | if (XPC_MSG_SIZE(payload_size) > XPC_MSG_MAX_SIZE) |
145 | return xpPayloadTooBig; |
146 | |
147 | registration = &xpc_registrations[ch_number]; |
148 | |
149 | if (mutex_lock_interruptible(®istration->mutex) != 0) |
150 | return xpInterrupted; |
151 | |
152 | /* if XPC_CHANNEL_REGISTERED(ch_number) */ |
153 | if (registration->func != NULL) { |
154 | mutex_unlock(lock: ®istration->mutex); |
155 | return xpAlreadyRegistered; |
156 | } |
157 | |
158 | /* register the channel for connection */ |
159 | registration->entry_size = XPC_MSG_SIZE(payload_size); |
160 | registration->nentries = nentries; |
161 | registration->assigned_limit = assigned_limit; |
162 | registration->idle_limit = idle_limit; |
163 | registration->key = key; |
164 | registration->func = func; |
165 | |
166 | mutex_unlock(lock: ®istration->mutex); |
167 | |
168 | if (xpc_interface.connect) |
169 | xpc_interface.connect(ch_number); |
170 | |
171 | return xpSuccess; |
172 | } |
173 | EXPORT_SYMBOL_GPL(xpc_connect); |
174 | |
175 | /* |
176 | * Remove the registration for automatic connection of the specified channel |
177 | * when a partition comes up. |
178 | * |
179 | * Before returning this xpc_disconnect() will wait for all connections on the |
180 | * specified channel have been closed/torndown. So the caller can be assured |
181 | * that they will not be receiving any more callouts from XPC to their |
182 | * function registered via xpc_connect(). |
183 | * |
184 | * Arguments: |
185 | * |
186 | * ch_number - channel # to unregister. |
187 | */ |
188 | void |
189 | xpc_disconnect(int ch_number) |
190 | { |
191 | struct xpc_registration *registration; |
192 | |
193 | DBUG_ON(ch_number < 0 || ch_number >= XPC_MAX_NCHANNELS); |
194 | |
195 | registration = &xpc_registrations[ch_number]; |
196 | |
197 | /* |
198 | * We've decided not to make this a down_interruptible(), since we |
199 | * figured XPC's users will just turn around and call xpc_disconnect() |
200 | * again anyways, so we might as well wait, if need be. |
201 | */ |
202 | mutex_lock(®istration->mutex); |
203 | |
204 | /* if !XPC_CHANNEL_REGISTERED(ch_number) */ |
205 | if (registration->func == NULL) { |
206 | mutex_unlock(lock: ®istration->mutex); |
207 | return; |
208 | } |
209 | |
210 | /* remove the connection registration for the specified channel */ |
211 | registration->func = NULL; |
212 | registration->key = NULL; |
213 | registration->nentries = 0; |
214 | registration->entry_size = 0; |
215 | registration->assigned_limit = 0; |
216 | registration->idle_limit = 0; |
217 | |
218 | if (xpc_interface.disconnect) |
219 | xpc_interface.disconnect(ch_number); |
220 | |
221 | mutex_unlock(lock: ®istration->mutex); |
222 | |
223 | return; |
224 | } |
225 | EXPORT_SYMBOL_GPL(xpc_disconnect); |
226 | |
227 | static int __init |
228 | xp_init(void) |
229 | { |
230 | enum xp_retval ret; |
231 | int ch_number; |
232 | |
233 | /* initialize the connection registration mutex */ |
234 | for (ch_number = 0; ch_number < XPC_MAX_NCHANNELS; ch_number++) |
235 | mutex_init(&xpc_registrations[ch_number].mutex); |
236 | |
237 | if (is_uv_system()) |
238 | ret = xp_init_uv(); |
239 | else |
240 | ret = 0; |
241 | |
242 | if (ret != xpSuccess) |
243 | return ret; |
244 | |
245 | return 0; |
246 | } |
247 | |
248 | module_init(xp_init); |
249 | |
250 | static void __exit |
251 | xp_exit(void) |
252 | { |
253 | if (is_uv_system()) |
254 | xp_exit_uv(); |
255 | } |
256 | |
257 | module_exit(xp_exit); |
258 | |
259 | MODULE_AUTHOR("Silicon Graphics, Inc." ); |
260 | MODULE_DESCRIPTION("Cross Partition (XP) base" ); |
261 | MODULE_LICENSE("GPL" ); |
262 | |