drivers/misc/sgi-xp/xp.h

   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  * External Cross Partition (XP) structures and defines.
  11  */
  12
  13 #ifndef _DRIVERS_MISC_SGIXP_XP_H
  14 #define _DRIVERS_MISC_SGIXP_XP_H
  15
  16 #include <linux/mutex.h>
  17
  18 #if defined CONFIG_X86_UV || defined CONFIG_IA64_SGI_UV
  19 #include <asm/uv/uv.h>
  20 #define is_uv()         is_uv_system()
  21 #endif
  22
  23 #ifndef is_uv
  24 #define is_uv()         0
  25 #endif
  26
  27 #ifdef USE_DBUG_ON
  28 #define DBUG_ON(condition)      BUG_ON(condition)
  29 #else
  30 #define DBUG_ON(condition)
  31 #endif
  32
  33 /*
  34  * Define the maximum number of partitions the system can possibly support.
  35  * It is based on the maximum number of hardware partitionable regions. The
  36  * term 'region' in this context refers to the minimum number of nodes that
  37  * can comprise an access protection grouping. The access protection is in
  38  * regards to memory, IPI and IOI.
  39  *
  40  * The maximum number of hardware partitionable regions is equal to the
  41  * maximum number of nodes in the entire system divided by the minimum number
  42  * of nodes that comprise an access protection grouping.
  43  */
  44 #define XP_MAX_NPARTITIONS_SN2  64
  45 #define XP_MAX_NPARTITIONS_UV   256
  46
  47 /*
  48  * XPC establishes channel connections between the local partition and any
  49  * other partition that is currently up. Over these channels, kernel-level
  50  * `users' can communicate with their counterparts on the other partitions.
  51  *
  52  * If the need for additional channels arises, one can simply increase
  53  * XPC_MAX_NCHANNELS accordingly. If the day should come where that number
  54  * exceeds the absolute MAXIMUM number of channels possible (eight), then one
  55  * will need to make changes to the XPC code to accommodate for this.
  56  *
  57  * The absolute maximum number of channels possible is limited to eight for
  58  * performance reasons on sn2 hardware. The internal cross partition structures
  59  * require sixteen bytes per channel, and eight allows all of this
  60  * interface-shared info to fit in one 128-byte cacheline.
  61  */
  62 #define XPC_MEM_CHANNEL         0       /* memory channel number */
  63 #define XPC_NET_CHANNEL         1       /* network channel number */
  64
  65 #define XPC_MAX_NCHANNELS       2       /* max #of channels allowed */
  66
  67 #if XPC_MAX_NCHANNELS > 8
  68 #error  XPC_MAX_NCHANNELS exceeds absolute MAXIMUM possible.
  69 #endif
  70
  71 /*
  72  * Define macro, XPC_MSG_SIZE(), is provided for the user
  73  * that wants to fit as many msg entries as possible in a given memory size
  74  * (e.g. a memory page).
  75  */
  76 #define XPC_MSG_MAX_SIZE        128
  77 #define XPC_MSG_HDR_MAX_SIZE    16
  78 #define XPC_MSG_PAYLOAD_MAX_SIZE (XPC_MSG_MAX_SIZE - XPC_MSG_HDR_MAX_SIZE)
  79
  80 #define XPC_MSG_SIZE(_payload_size) \
  81                                 ALIGN(XPC_MSG_HDR_MAX_SIZE + (_payload_size), \
  82                                       is_uv() ? 64 : 128)
  83
  84
  85 /*
  86  * Define the return values and values passed to user's callout functions.
  87  * (It is important to add new value codes at the end just preceding
  88  * xpUnknownReason, which must have the highest numerical value.)
  89  */
  90 enum xp_retval {
  91         xpSuccess = 0,
  92
  93         xpNotConnected,         /*  1: channel is not connected */
  94         xpConnected,            /*  2: channel connected (opened) */
  95         xpRETIRED1,             /*  3: (formerly xpDisconnected) */
  96
  97         xpMsgReceived,          /*  4: message received */
  98         xpMsgDelivered,         /*  5: message delivered and acknowledged */
  99
 100         xpRETIRED2,             /*  6: (formerly xpTransferFailed) */
 101
 102         xpNoWait,               /*  7: operation would require wait */
 103         xpRetry,                /*  8: retry operation */
 104         xpTimeout,              /*  9: timeout in xpc_allocate_msg_wait() */
 105         xpInterrupted,          /* 10: interrupted wait */
 106
 107         xpUnequalMsgSizes,      /* 11: message size disparity between sides */
 108         xpInvalidAddress,       /* 12: invalid address */
 109
 110         xpNoMemory,             /* 13: no memory available for XPC structures */
 111         xpLackOfResources,      /* 14: insufficient resources for operation */
 112         xpUnregistered,         /* 15: channel is not registered */
 113         xpAlreadyRegistered,    /* 16: channel is already registered */
 114
 115         xpPartitionDown,        /* 17: remote partition is down */
 116         xpNotLoaded,            /* 18: XPC module is not loaded */
 117         xpUnloading,            /* 19: this side is unloading XPC module */
 118
 119         xpBadMagic,             /* 20: XPC MAGIC string not found */
 120
 121         xpReactivating,         /* 21: remote partition was reactivated */
 122
 123         xpUnregistering,        /* 22: this side is unregistering channel */
 124         xpOtherUnregistering,   /* 23: other side is unregistering channel */
 125
 126         xpCloneKThread,         /* 24: cloning kernel thread */
 127         xpCloneKThreadFailed,   /* 25: cloning kernel thread failed */
 128
 129         xpNoHeartbeat,          /* 26: remote partition has no heartbeat */
 130
 131         xpPioReadError,         /* 27: PIO read error */
 132         xpPhysAddrRegFailed,    /* 28: registration of phys addr range failed */
 133
 134         xpRETIRED3,             /* 29: (formerly xpBteDirectoryError) */
 135         xpRETIRED4,             /* 30: (formerly xpBtePoisonError) */
 136         xpRETIRED5,             /* 31: (formerly xpBteWriteError) */
 137         xpRETIRED6,             /* 32: (formerly xpBteAccessError) */
 138         xpRETIRED7,             /* 33: (formerly xpBtePWriteError) */
 139         xpRETIRED8,             /* 34: (formerly xpBtePReadError) */
 140         xpRETIRED9,             /* 35: (formerly xpBteTimeOutError) */
 141         xpRETIRED10,            /* 36: (formerly xpBteXtalkError) */
 142         xpRETIRED11,            /* 37: (formerly xpBteNotAvailable) */
 143         xpRETIRED12,            /* 38: (formerly xpBteUnmappedError) */
 144
 145         xpBadVersion,           /* 39: bad version number */
 146         xpVarsNotSet,           /* 40: the XPC variables are not set up */
 147         xpNoRsvdPageAddr,       /* 41: unable to get rsvd page's phys addr */
 148         xpInvalidPartid,        /* 42: invalid partition ID */
 149         xpLocalPartid,          /* 43: local partition ID */
 150
 151         xpOtherGoingDown,       /* 44: other side going down, reason unknown */
 152         xpSystemGoingDown,      /* 45: system is going down, reason unknown */
 153         xpSystemHalt,           /* 46: system is being halted */
 154         xpSystemReboot,         /* 47: system is being rebooted */
 155         xpSystemPoweroff,       /* 48: system is being powered off */
 156
 157         xpDisconnecting,        /* 49: channel disconnecting (closing) */
 158
 159         xpOpenCloseError,       /* 50: channel open/close protocol error */
 160
 161         xpDisconnected,         /* 51: channel disconnected (closed) */
 162
 163         xpBteCopyError,         /* 52: bte_copy() returned error */
 164         xpSalError,             /* 53: sn SAL error */
 165         xpRsvdPageNotSet,       /* 54: the reserved page is not set up */
 166         xpPayloadTooBig,        /* 55: payload too large for message slot */
 167
 168         xpUnsupported,          /* 56: unsupported functionality or resource */
 169         xpNeedMoreInfo,         /* 57: more info is needed by SAL */
 170
 171         xpGruCopyError,         /* 58: gru_copy_gru() returned error */
 172         xpGruSendMqError,       /* 59: gru send message queue related error */
 173
 174         xpBadChannelNumber,     /* 60: invalid channel number */
 175         xpBadMsgType,           /* 61: invalid message type */
 176         xpBiosError,            /* 62: BIOS error */
 177
 178         xpUnknownReason         /* 63: unknown reason - must be last in enum */
 179 };
 180
 181 /*
 182  * Define the callout function type used by XPC to update the user on
 183  * connection activity and state changes via the user function registered
 184  * by xpc_connect().
 185  *
 186  * Arguments:
 187  *
 188  *      reason - reason code.
 189  *      partid - partition ID associated with condition.
 190  *      ch_number - channel # associated with condition.
 191  *      data - pointer to optional data.
 192  *      key - pointer to optional user-defined value provided as the "key"
 193  *            argument to xpc_connect().
 194  *
 195  * A reason code of xpConnected indicates that a connection has been
 196  * established to the specified partition on the specified channel. The data
 197  * argument indicates the max number of entries allowed in the message queue.
 198  *
 199  * A reason code of xpMsgReceived indicates that a XPC message arrived from
 200  * the specified partition on the specified channel. The data argument
 201  * specifies the address of the message's payload. The user must call
 202  * xpc_received() when finished with the payload.
 203  *
 204  * All other reason codes indicate failure. The data argmument is NULL.
 205  * When a failure reason code is received, one can assume that the channel
 206  * is not connected.
 207  */
 208 typedef void (*xpc_channel_func) (enum xp_retval reason, short partid,
 209                                   int ch_number, void *data, void *key);
 210
 211 /*
 212  * Define the callout function type used by XPC to notify the user of
 213  * messages received and delivered via the user function registered by
 214  * xpc_send_notify().
 215  *
 216  * Arguments:
 217  *
 218  *      reason - reason code.
 219  *      partid - partition ID associated with condition.
 220  *      ch_number - channel # associated with condition.
 221  *      key - pointer to optional user-defined value provided as the "key"
 222  *            argument to xpc_send_notify().
 223  *
 224  * A reason code of xpMsgDelivered indicates that the message was delivered
 225  * to the intended recipient and that they have acknowledged its receipt by
 226  * calling xpc_received().
 227  *
 228  * All other reason codes indicate failure.
 229  *
 230  * NOTE: The user defined function must be callable by an interrupt handler
 231  *       and thus cannot block.
 232  */
 233 typedef void (*xpc_notify_func) (enum xp_retval reason, short partid,
 234                                  int ch_number, void *key);
 235
 236 /*
 237  * The following is a registration entry. There is a global array of these,
 238  * one per channel. It is used to record the connection registration made
 239  * by the users of XPC. As long as a registration entry exists, for any
 240  * partition that comes up, XPC will attempt to establish a connection on
 241  * that channel. Notification that a connection has been made will occur via
 242  * the xpc_channel_func function.
 243  *
 244  * The 'func' field points to the function to call when aynchronous
 245  * notification is required for such events as: a connection established/lost,
 246  * or an incoming message received, or an error condition encountered. A
 247  * non-NULL 'func' field indicates that there is an active registration for
 248  * the channel.
 249  */
 250 struct xpc_registration {
 251         struct mutex mutex;
 252         xpc_channel_func func;  /* function to call */
 253         void *key;              /* pointer to user's key */
 254         u16 nentries;           /* #of msg entries in local msg queue */
 255         u16 entry_size;         /* message queue's message entry size */
 256         u32 assigned_limit;     /* limit on #of assigned kthreads */
 257         u32 idle_limit;         /* limit on #of idle kthreads */
 258 } ____cacheline_aligned;
 259
 260 #define XPC_CHANNEL_REGISTERED(_c)      (xpc_registrations[_c].func != NULL)
 261
 262 /* the following are valid xpc_send() or xpc_send_notify() flags */
 263 #define XPC_WAIT        0       /* wait flag */
 264 #define XPC_NOWAIT      1       /* no wait flag */
 265
 266 struct xpc_interface {
 267         void (*connect) (int);
 268         void (*disconnect) (int);
 269         enum xp_retval (*send) (short, int, u32, void *, u16);
 270         enum xp_retval (*send_notify) (short, int, u32, void *, u16,
 271                                         xpc_notify_func, void *);
 272         void (*received) (short, int, void *);
 273         enum xp_retval (*partid_to_nasids) (short, void *);
 274 };
 275
 276 extern struct xpc_interface xpc_interface;
 277
 278 extern void xpc_set_interface(void (*)(int),
 279                               void (*)(int),
 280                               enum xp_retval (*)(short, int, u32, void *, u16),
 281                               enum xp_retval (*)(short, int, u32, void *, u16,
 282                                                  xpc_notify_func, void *),
 283                               void (*)(short, int, void *),
 284                               enum xp_retval (*)(short, void *));
 285 extern void xpc_clear_interface(void);
 286
 287 extern enum xp_retval xpc_connect(int, xpc_channel_func, void *, u16,
 288                                    u16, u32, u32);
 289 extern void xpc_disconnect(int);
 290
 291 static inline enum xp_retval
 292 xpc_send(short partid, int ch_number, u32 flags, void *payload,
 293          u16 payload_size)
 294 {
 295         if (!xpc_interface.send)
 296                 return xpNotLoaded;
 297
 298         return xpc_interface.send(partid, ch_number, flags, payload,
 299                                   payload_size);
 300 }
 301
 302 static inline enum xp_retval
 303 xpc_send_notify(short partid, int ch_number, u32 flags, void *payload,
 304                 u16 payload_size, xpc_notify_func func, void *key)
 305 {
 306         if (!xpc_interface.send_notify)
 307                 return xpNotLoaded;
 308
 309         return xpc_interface.send_notify(partid, ch_number, flags, payload,
 310                                          payload_size, func, key);
 311 }
 312
 313 static inline void
 314 xpc_received(short partid, int ch_number, void *payload)
 315 {
 316         if (xpc_interface.received)
 317                 xpc_interface.received(partid, ch_number, payload);
 318 }
 319
 320 static inline enum xp_retval
 321 xpc_partid_to_nasids(short partid, void *nasids)
 322 {
 323         if (!xpc_interface.partid_to_nasids)
 324                 return xpNotLoaded;
 325
 326         return xpc_interface.partid_to_nasids(partid, nasids);
 327 }
 328
 329 extern short xp_max_npartitions;
 330 extern short xp_partition_id;
 331 extern u8 xp_region_size;
 332
 333 extern unsigned long (*xp_pa) (void *);
 334 extern unsigned long (*xp_socket_pa) (unsigned long);
 335 extern enum xp_retval (*xp_remote_memcpy) (unsigned long, const unsigned long,
 336                        size_t);
 337 extern int (*xp_cpu_to_nasid) (int);
 338 extern enum xp_retval (*xp_expand_memprotect) (unsigned long, unsigned long);
 339 extern enum xp_retval (*xp_restrict_memprotect) (unsigned long, unsigned long);
 340
 341 extern u64 xp_nofault_PIOR_target;
 342 extern int xp_nofault_PIOR(void *);
 343 extern int xp_error_PIOR(void);
 344
 345 extern struct device *xp;
 346 extern enum xp_retval xp_init_uv(void);
 347 extern void xp_exit_uv(void);
 348
 349 #endif /* _DRIVERS_MISC_SGIXP_XP_H */