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 * Copyright (c) 2004-2008 Silicon Graphics, Inc. All Rights Reserved. 7 */ 8 9 /* 10 * Cross Partition (XP) base. 11 * 12 * XP provides a base from which its users can interact 13 * with XPC, yet not be dependent on XPC. 14 * 15 */ 16 17 #include <linux/module.h> 18 #include <linux/device.h> 19 #include "xp.h" 20 21 /* define the XP debug device structures to be used with dev_dbg() et al */ 22 23 struct device_driver xp_dbg_name = { 24 .name = "xp" 25 }; 26 27 struct device xp_dbg_subname = { 28 .bus_id = {0}, /* set to "" */ 29 .driver = &xp_dbg_name 30 }; 31 32 struct device *xp = &xp_dbg_subname; 33 34 /* max #of partitions possible */ 35 short xp_max_npartitions; 36 EXPORT_SYMBOL_GPL(xp_max_npartitions); 37 38 short xp_partition_id; 39 EXPORT_SYMBOL_GPL(xp_partition_id); 40 41 u8 xp_region_size; 42 EXPORT_SYMBOL_GPL(xp_region_size); 43 44 enum xp_retval (*xp_remote_memcpy) (void *dst, const void *src, size_t len); 45 EXPORT_SYMBOL_GPL(xp_remote_memcpy); 46 47 int (*xp_cpu_to_nasid) (int cpuid); 48 EXPORT_SYMBOL_GPL(xp_cpu_to_nasid); 49 50 /* 51 * xpc_registrations[] keeps track of xpc_connect()'s done by the kernel-level 52 * users of XPC. 53 */ 54 struct xpc_registration xpc_registrations[XPC_MAX_NCHANNELS]; 55 EXPORT_SYMBOL_GPL(xpc_registrations); 56 57 /* 58 * Initialize the XPC interface to indicate that XPC isn't loaded. 59 */ 60 static enum xp_retval 61 xpc_notloaded(void) 62 { 63 return xpNotLoaded; 64 } 65 66 struct xpc_interface xpc_interface = { 67 (void (*)(int))xpc_notloaded, 68 (void (*)(int))xpc_notloaded, 69 (enum xp_retval(*)(short, int, u32, void *, u16))xpc_notloaded, 70 (enum xp_retval(*)(short, int, u32, void *, u16, xpc_notify_func, 71 void *))xpc_notloaded, 72 (void (*)(short, int, void *))xpc_notloaded, 73 (enum xp_retval(*)(short, void *))xpc_notloaded 74 }; 75 EXPORT_SYMBOL_GPL(xpc_interface); 76 77 /* 78 * XPC calls this when it (the XPC module) has been loaded. 79 */ 80 void 81 xpc_set_interface(void (*connect) (int), 82 void (*disconnect) (int), 83 enum xp_retval (*send) (short, int, u32, void *, u16), 84 enum xp_retval (*send_notify) (short, int, u32, void *, u16, 85 xpc_notify_func, void *), 86 void (*received) (short, int, void *), 87 enum xp_retval (*partid_to_nasids) (short, void *)) 88 { 89 xpc_interface.connect = connect; 90 xpc_interface.disconnect = disconnect; 91 xpc_interface.send = send; 92 xpc_interface.send_notify = send_notify; 93 xpc_interface.received = received; 94 xpc_interface.partid_to_nasids = partid_to_nasids; 95 } 96 EXPORT_SYMBOL_GPL(xpc_set_interface); 97 98 /* 99 * XPC calls this when it (the XPC module) is being unloaded. 100 */ 101 void 102 xpc_clear_interface(void) 103 { 104 xpc_interface.connect = (void (*)(int))xpc_notloaded; 105 xpc_interface.disconnect = (void (*)(int))xpc_notloaded; 106 xpc_interface.send = (enum xp_retval(*)(short, int, u32, void *, u16)) 107 xpc_notloaded; 108 xpc_interface.send_notify = (enum xp_retval(*)(short, int, u32, void *, 109 u16, xpc_notify_func, 110 void *))xpc_notloaded; 111 xpc_interface.received = (void (*)(short, int, void *)) 112 xpc_notloaded; 113 xpc_interface.partid_to_nasids = (enum xp_retval(*)(short, void *)) 114 xpc_notloaded; 115 } 116 EXPORT_SYMBOL_GPL(xpc_clear_interface); 117 118 /* 119 * Register for automatic establishment of a channel connection whenever 120 * a partition comes up. 121 * 122 * Arguments: 123 * 124 * ch_number - channel # to register for connection. 125 * func - function to call for asynchronous notification of channel 126 * state changes (i.e., connection, disconnection, error) and 127 * the arrival of incoming messages. 128 * key - pointer to optional user-defined value that gets passed back 129 * to the user on any callouts made to func. 130 * payload_size - size in bytes of the XPC message's payload area which 131 * contains a user-defined message. The user should make 132 * this large enough to hold their largest message. 133 * nentries - max #of XPC message entries a message queue can contain. 134 * The actual number, which is determined when a connection 135 * is established and may be less then requested, will be 136 * passed to the user via the xpConnected callout. 137 * assigned_limit - max number of kthreads allowed to be processing 138 * messages (per connection) at any given instant. 139 * idle_limit - max number of kthreads allowed to be idle at any given 140 * instant. 141 */ 142 enum xp_retval 143 xpc_connect(int ch_number, xpc_channel_func func, void *key, u16 payload_size, 144 u16 nentries, u32 assigned_limit, u32 idle_limit) 145 { 146 struct xpc_registration *registration; 147 148 DBUG_ON(ch_number < 0 || ch_number >= XPC_MAX_NCHANNELS); 149 DBUG_ON(payload_size == 0 || nentries == 0); 150 DBUG_ON(func == NULL); 151 DBUG_ON(assigned_limit == 0 || idle_limit > assigned_limit); 152 153 registration = &xpc_registrations[ch_number]; 154 155 if (mutex_lock_interruptible(®istration->mutex) != 0) 156 return xpInterrupted; 157 158 /* if XPC_CHANNEL_REGISTERED(ch_number) */ 159 if (registration->func != NULL) { 160 mutex_unlock(®istration->mutex); 161 return xpAlreadyRegistered; 162 } 163 164 /* register the channel for connection */ 165 registration->msg_size = XPC_MSG_SIZE(payload_size); 166 registration->nentries = nentries; 167 registration->assigned_limit = assigned_limit; 168 registration->idle_limit = idle_limit; 169 registration->key = key; 170 registration->func = func; 171 172 mutex_unlock(®istration->mutex); 173 174 xpc_interface.connect(ch_number); 175 176 return xpSuccess; 177 } 178 EXPORT_SYMBOL_GPL(xpc_connect); 179 180 /* 181 * Remove the registration for automatic connection of the specified channel 182 * when a partition comes up. 183 * 184 * Before returning this xpc_disconnect() will wait for all connections on the 185 * specified channel have been closed/torndown. So the caller can be assured 186 * that they will not be receiving any more callouts from XPC to their 187 * function registered via xpc_connect(). 188 * 189 * Arguments: 190 * 191 * ch_number - channel # to unregister. 192 */ 193 void 194 xpc_disconnect(int ch_number) 195 { 196 struct xpc_registration *registration; 197 198 DBUG_ON(ch_number < 0 || ch_number >= XPC_MAX_NCHANNELS); 199 200 registration = &xpc_registrations[ch_number]; 201 202 /* 203 * We've decided not to make this a down_interruptible(), since we 204 * figured XPC's users will just turn around and call xpc_disconnect() 205 * again anyways, so we might as well wait, if need be. 206 */ 207 mutex_lock(®istration->mutex); 208 209 /* if !XPC_CHANNEL_REGISTERED(ch_number) */ 210 if (registration->func == NULL) { 211 mutex_unlock(®istration->mutex); 212 return; 213 } 214 215 /* remove the connection registration for the specified channel */ 216 registration->func = NULL; 217 registration->key = NULL; 218 registration->nentries = 0; 219 registration->msg_size = 0; 220 registration->assigned_limit = 0; 221 registration->idle_limit = 0; 222 223 xpc_interface.disconnect(ch_number); 224 225 mutex_unlock(®istration->mutex); 226 227 return; 228 } 229 EXPORT_SYMBOL_GPL(xpc_disconnect); 230 231 int __init 232 xp_init(void) 233 { 234 enum xp_retval ret; 235 int ch_number; 236 237 if (is_shub()) 238 ret = xp_init_sn2(); 239 else if (is_uv()) 240 ret = xp_init_uv(); 241 else 242 ret = xpUnsupported; 243 244 if (ret != xpSuccess) 245 return -ENODEV; 246 247 /* initialize the connection registration mutex */ 248 for (ch_number = 0; ch_number < XPC_MAX_NCHANNELS; ch_number++) 249 mutex_init(&xpc_registrations[ch_number].mutex); 250 251 return 0; 252 } 253 254 module_init(xp_init); 255 256 void __exit 257 xp_exit(void) 258 { 259 if (is_shub()) 260 xp_exit_sn2(); 261 else if (is_uv()) 262 xp_exit_uv(); 263 } 264 265 module_exit(xp_exit); 266 267 MODULE_AUTHOR("Silicon Graphics, Inc."); 268 MODULE_DESCRIPTION("Cross Partition (XP) base"); 269 MODULE_LICENSE("GPL"); 270