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(®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(®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(®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(®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