include/asm-ia64/sn/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) 2004-2005 Silicon Graphics, Inc. All rights reserved.
   7  */
   8
   9
  10 /*
  11  * External Cross Partition (XP) structures and defines.
  12  */
  13
  14
  15 #ifndef _ASM_IA64_SN_XP_H
  16 #define _ASM_IA64_SN_XP_H
  17
  18
  19 #include <linux/cache.h>
  20 #include <linux/hardirq.h>
  21 #include <linux/mutex.h>
  22 #include <asm/sn/types.h>
  23 #include <asm/sn/bte.h>
  24
  25
  26 #ifdef USE_DBUG_ON
  27 #define DBUG_ON(condition)      BUG_ON(condition)
  28 #else
  29 #define DBUG_ON(condition)
  30 #endif
  31
  32
  33 /*
  34  * Define the maximum number of logically defined partitions the system
  35  * can support. It is constrained by the maximum number of hardware
  36  * partitionable regions. The term 'region' in this context refers to the
  37  * minimum number of nodes that can comprise an access protection grouping.
  38  * The access protection is in 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_PARTITIONS       64
  45
  46
  47 /*
  48  * Define the number of u64s required to represent all the C-brick nasids
  49  * as a bitmap.  The cross-partition kernel modules deal only with
  50  * C-brick nasids, thus the need for bitmaps which don't account for
  51  * odd-numbered (non C-brick) nasids.
  52  */
  53 #define XP_MAX_PHYSNODE_ID      (MAX_NUMALINK_NODES / 2)
  54 #define XP_NASID_MASK_BYTES     ((XP_MAX_PHYSNODE_ID + 7) / 8)
  55 #define XP_NASID_MASK_WORDS     ((XP_MAX_PHYSNODE_ID + 63) / 64)
  56
  57
  58 /*
  59  * Wrapper for bte_copy() that should it return a failure status will retry
  60  * the bte_copy() once in the hope that the failure was due to a temporary
  61  * aberration (i.e., the link going down temporarily).
  62  *
  63  * See bte_copy for definition of the input parameters.
  64  *
  65  * Note: xp_bte_copy() should never be called while holding a spinlock.
  66  */
  67 static inline bte_result_t
  68 xp_bte_copy(u64 src, u64 dest, u64 len, u64 mode, void *notification)
  69 {
  70         bte_result_t ret;
  71
  72
  73         ret = bte_copy(src, dest, len, mode, notification);
  74
  75         if (ret != BTE_SUCCESS) {
  76                 if (!in_interrupt()) {
  77                         cond_resched();
  78                 }
  79                 ret = bte_copy(src, dest, len, mode, notification);
  80         }
  81
  82         return ret;
  83 }
  84
  85
  86 /*
  87  * XPC establishes channel connections between the local partition and any
  88  * other partition that is currently up. Over these channels, kernel-level
  89  * `users' can communicate with their counterparts on the other partitions.
  90  *
  91  * The maxinum number of channels is limited to eight. For performance reasons,
  92  * the internal cross partition structures require sixteen bytes per channel,
  93  * and eight allows all of this interface-shared info to fit in one cache line.
  94  *
  95  * XPC_NCHANNELS reflects the total number of channels currently defined.
  96  * If the need for additional channels arises, one can simply increase
  97  * XPC_NCHANNELS accordingly. If the day should come where that number
  98  * exceeds the MAXIMUM number of channels allowed (eight), then one will need
  99  * to make changes to the XPC code to allow for this.
 100  */
 101 #define XPC_MEM_CHANNEL         0       /* memory channel number */
 102 #define XPC_NET_CHANNEL         1       /* network channel number */
 103
 104 #define XPC_NCHANNELS           2       /* #of defined channels */
 105 #define XPC_MAX_NCHANNELS       8       /* max #of channels allowed */
 106
 107 #if XPC_NCHANNELS > XPC_MAX_NCHANNELS
 108 #error  XPC_NCHANNELS exceeds MAXIMUM allowed.
 109 #endif
 110
 111
 112 /*
 113  * The format of an XPC message is as follows:
 114  *
 115  *      +-------+--------------------------------+
 116  *      | flags |////////////////////////////////|
 117  *      +-------+--------------------------------+
 118  *      |             message #                  |
 119  *      +----------------------------------------+
 120  *      |     payload (user-defined message)     |
 121  *      |                                        |
 122  *                      :
 123  *      |                                        |
 124  *      +----------------------------------------+
 125  *
 126  * The size of the payload is defined by the user via xpc_connect(). A user-
 127  * defined message resides in the payload area.
 128  *
 129  * The user should have no dealings with the message header, but only the
 130  * message's payload. When a message entry is allocated (via xpc_allocate())
 131  * a pointer to the payload area is returned and not the actual beginning of
 132  * the XPC message. The user then constructs a message in the payload area
 133  * and passes that pointer as an argument on xpc_send() or xpc_send_notify().
 134  *
 135  * The size of a message entry (within a message queue) must be a cacheline
 136  * sized multiple in order to facilitate the BTE transfer of messages from one
 137  * message queue to another. A macro, XPC_MSG_SIZE(), is provided for the user
 138  * that wants to fit as many msg entries as possible in a given memory size
 139  * (e.g. a memory page).
 140  */
 141 struct xpc_msg {
 142         u8 flags;               /* FOR XPC INTERNAL USE ONLY */
 143         u8 reserved[7];         /* FOR XPC INTERNAL USE ONLY */
 144         s64 number;             /* FOR XPC INTERNAL USE ONLY */
 145
 146         u64 payload;            /* user defined portion of message */
 147 };
 148
 149
 150 #define XPC_MSG_PAYLOAD_OFFSET  (u64) (&((struct xpc_msg *)0)->payload)
 151 #define XPC_MSG_SIZE(_payload_size) \
 152                 L1_CACHE_ALIGN(XPC_MSG_PAYLOAD_OFFSET + (_payload_size))
 153
 154
 155 /*
 156  * Define the return values and values passed to user's callout functions.
 157  * (It is important to add new value codes at the end just preceding
 158  * xpcUnknownReason, which must have the highest numerical value.)
 159  */
 160 enum xpc_retval {
 161         xpcSuccess = 0,
 162
 163         xpcNotConnected,        /*  1: channel is not connected */
 164         xpcConnected,           /*  2: channel connected (opened) */
 165         xpcRETIRED1,            /*  3: (formerly xpcDisconnected) */
 166
 167         xpcMsgReceived,         /*  4: message received */
 168         xpcMsgDelivered,        /*  5: message delivered and acknowledged */
 169
 170         xpcRETIRED2,            /*  6: (formerly xpcTransferFailed) */
 171
 172         xpcNoWait,              /*  7: operation would require wait */
 173         xpcRetry,               /*  8: retry operation */
 174         xpcTimeout,             /*  9: timeout in xpc_allocate_msg_wait() */
 175         xpcInterrupted,         /* 10: interrupted wait */
 176
 177         xpcUnequalMsgSizes,     /* 11: message size disparity between sides */
 178         xpcInvalidAddress,      /* 12: invalid address */
 179
 180         xpcNoMemory,            /* 13: no memory available for XPC structures */
 181         xpcLackOfResources,     /* 14: insufficient resources for operation */
 182         xpcUnregistered,        /* 15: channel is not registered */
 183         xpcAlreadyRegistered,   /* 16: channel is already registered */
 184
 185         xpcPartitionDown,       /* 17: remote partition is down */
 186         xpcNotLoaded,           /* 18: XPC module is not loaded */
 187         xpcUnloading,           /* 19: this side is unloading XPC module */
 188
 189         xpcBadMagic,            /* 20: XPC MAGIC string not found */
 190
 191         xpcReactivating,        /* 21: remote partition was reactivated */
 192
 193         xpcUnregistering,       /* 22: this side is unregistering channel */
 194         xpcOtherUnregistering,  /* 23: other side is unregistering channel */
 195
 196         xpcCloneKThread,        /* 24: cloning kernel thread */
 197         xpcCloneKThreadFailed,  /* 25: cloning kernel thread failed */
 198
 199         xpcNoHeartbeat,         /* 26: remote partition has no heartbeat */
 200
 201         xpcPioReadError,        /* 27: PIO read error */
 202         xpcPhysAddrRegFailed,   /* 28: registration of phys addr range failed */
 203
 204         xpcBteDirectoryError,   /* 29: maps to BTEFAIL_DIR */
 205         xpcBtePoisonError,      /* 30: maps to BTEFAIL_POISON */
 206         xpcBteWriteError,       /* 31: maps to BTEFAIL_WERR */
 207         xpcBteAccessError,      /* 32: maps to BTEFAIL_ACCESS */
 208         xpcBtePWriteError,      /* 33: maps to BTEFAIL_PWERR */
 209         xpcBtePReadError,       /* 34: maps to BTEFAIL_PRERR */
 210         xpcBteTimeOutError,     /* 35: maps to BTEFAIL_TOUT */
 211         xpcBteXtalkError,       /* 36: maps to BTEFAIL_XTERR */
 212         xpcBteNotAvailable,     /* 37: maps to BTEFAIL_NOTAVAIL */
 213         xpcBteUnmappedError,    /* 38: unmapped BTEFAIL_ error */
 214
 215         xpcBadVersion,          /* 39: bad version number */
 216         xpcVarsNotSet,          /* 40: the XPC variables are not set up */
 217         xpcNoRsvdPageAddr,      /* 41: unable to get rsvd page's phys addr */
 218         xpcInvalidPartid,       /* 42: invalid partition ID */
 219         xpcLocalPartid,         /* 43: local partition ID */
 220
 221         xpcOtherGoingDown,      /* 44: other side going down, reason unknown */
 222         xpcSystemGoingDown,     /* 45: system is going down, reason unknown */
 223         xpcSystemHalt,          /* 46: system is being halted */
 224         xpcSystemReboot,        /* 47: system is being rebooted */
 225         xpcSystemPoweroff,      /* 48: system is being powered off */
 226
 227         xpcDisconnecting,       /* 49: channel disconnecting (closing) */
 228
 229         xpcOpenCloseError,      /* 50: channel open/close protocol error */
 230
 231         xpcDisconnected,        /* 51: channel disconnected (closed) */
 232
 233         xpcUnknownReason        /* 52: unknown reason -- must be last in list */
 234 };
 235
 236
 237 /*
 238  * Define the callout function types used by XPC to update the user on
 239  * connection activity and state changes (via the user function registered by
 240  * xpc_connect()) and to notify them of messages received and delivered (via
 241  * the user function registered by xpc_send_notify()).
 242  *
 243  * The two function types are xpc_channel_func and xpc_notify_func and
 244  * both share the following arguments, with the exception of "data", which
 245  * only xpc_channel_func has.
 246  *
 247  * Arguments:
 248  *
 249  *      reason - reason code. (See following table.)
 250  *      partid - partition ID associated with condition.
 251  *      ch_number - channel # associated with condition.
 252  *      data - pointer to optional data. (See following table.)
 253  *      key - pointer to optional user-defined value provided as the "key"
 254  *            argument to xpc_connect() or xpc_send_notify().
 255  *
 256  * In the following table the "Optional Data" column applies to callouts made
 257  * to functions registered by xpc_connect(). A "NA" in that column indicates
 258  * that this reason code can be passed to functions registered by
 259  * xpc_send_notify() (i.e. they don't have data arguments).
 260  *
 261  * Also, the first three reason codes in the following table indicate
 262  * success, whereas the others indicate failure. When a failure reason code
 263  * is received, one can assume that the channel is not connected.
 264  *
 265  *
 266  * Reason Code          | Cause                          | Optional Data
 267  * =====================+================================+=====================
 268  * xpcConnected         | connection has been established| max #of entries
 269  *                      | to the specified partition on  | allowed in message
 270  *                      | the specified channel          | queue
 271  * ---------------------+--------------------------------+---------------------
 272  * xpcMsgReceived       | an XPC message arrived from    | address of payload
 273  *                      | the specified partition on the |
 274  *                      | specified channel              | [the user must call
 275  *                      |                                | xpc_received() when
 276  *                      |                                | finished with the
 277  *                      |                                | payload]
 278  * ---------------------+--------------------------------+---------------------
 279  * xpcMsgDelivered      | notification that the message  | NA
 280  *                      | was delivered to the intended  |
 281  *                      | recipient and that they have   |
 282  *                      | acknowledged its receipt by    |
 283  *                      | calling xpc_received()         |
 284  * =====================+================================+=====================
 285  * xpcUnequalMsgSizes   | can't connect to the specified | NULL
 286  *                      | partition on the specified     |
 287  *                      | channel because of mismatched  |
 288  *                      | message sizes                  |
 289  * ---------------------+--------------------------------+---------------------
 290  * xpcNoMemory          | insufficient memory avaiable   | NULL
 291  *                      | to allocate message queue      |
 292  * ---------------------+--------------------------------+---------------------
 293  * xpcLackOfResources   | lack of resources to create    | NULL
 294  *                      | the necessary kthreads to      |
 295  *                      | support the channel            |
 296  * ---------------------+--------------------------------+---------------------
 297  * xpcUnregistering     | this side's user has           | NULL or NA
 298  *                      | unregistered by calling        |
 299  *                      | xpc_disconnect()               |
 300  * ---------------------+--------------------------------+---------------------
 301  * xpcOtherUnregistering| the other side's user has      | NULL or NA
 302  *                      | unregistered by calling        |
 303  *                      | xpc_disconnect()               |
 304  * ---------------------+--------------------------------+---------------------
 305  * xpcNoHeartbeat       | the other side's XPC is no     | NULL or NA
 306  *                      | longer heartbeating            |
 307  *                      |                                |
 308  * ---------------------+--------------------------------+---------------------
 309  * xpcUnloading         | this side's XPC module is      | NULL or NA
 310  *                      | being unloaded                 |
 311  *                      |                                |
 312  * ---------------------+--------------------------------+---------------------
 313  * xpcOtherUnloading    | the other side's XPC module is | NULL or NA
 314  *                      | is being unloaded              |
 315  *                      |                                |
 316  * ---------------------+--------------------------------+---------------------
 317  * xpcPioReadError      | xp_nofault_PIOR() returned an  | NULL or NA
 318  *                      | error while sending an IPI     |
 319  *                      |                                |
 320  * ---------------------+--------------------------------+---------------------
 321  * xpcInvalidAddress    | the address either received or | NULL or NA
 322  *                      | sent by the specified partition|
 323  *                      | is invalid                     |
 324  * ---------------------+--------------------------------+---------------------
 325  * xpcBteNotAvailable   | attempt to pull data from the  | NULL or NA
 326  * xpcBtePoisonError    | specified partition over the   |
 327  * xpcBteWriteError     | specified channel via a        |
 328  * xpcBteAccessError    | bte_copy() failed              |
 329  * xpcBteTimeOutError   |                                |
 330  * xpcBteXtalkError     |                                |
 331  * xpcBteDirectoryError |                                |
 332  * xpcBteGenericError   |                                |
 333  * xpcBteUnmappedError  |                                |
 334  * ---------------------+--------------------------------+---------------------
 335  * xpcUnknownReason     | the specified channel to the   | NULL or NA
 336  *                      | specified partition was        |
 337  *                      | unavailable for unknown reasons|
 338  * =====================+================================+=====================
 339  */
 340
 341 typedef void (*xpc_channel_func)(enum xpc_retval reason, partid_t partid,
 342                 int ch_number, void *data, void *key);
 343
 344 typedef void (*xpc_notify_func)(enum xpc_retval reason, partid_t partid,
 345                 int ch_number, void *key);
 346
 347
 348 /*
 349  * The following is a registration entry. There is a global array of these,
 350  * one per channel. It is used to record the connection registration made
 351  * by the users of XPC. As long as a registration entry exists, for any
 352  * partition that comes up, XPC will attempt to establish a connection on
 353  * that channel. Notification that a connection has been made will occur via
 354  * the xpc_channel_func function.
 355  *
 356  * The 'func' field points to the function to call when aynchronous
 357  * notification is required for such events as: a connection established/lost,
 358  * or an incoming message received, or an error condition encountered. A
 359  * non-NULL 'func' field indicates that there is an active registration for
 360  * the channel.
 361  */
 362 struct xpc_registration {
 363         struct mutex mutex;
 364         xpc_channel_func func;          /* function to call */
 365         void *key;                      /* pointer to user's key */
 366         u16 nentries;                   /* #of msg entries in local msg queue */
 367         u16 msg_size;                   /* message queue's message size */
 368         u32 assigned_limit;             /* limit on #of assigned kthreads */
 369         u32 idle_limit;                 /* limit on #of idle kthreads */
 370 } ____cacheline_aligned;
 371
 372
 373 #define XPC_CHANNEL_REGISTERED(_c)      (xpc_registrations[_c].func != NULL)
 374
 375
 376 /* the following are valid xpc_allocate() flags */
 377 #define XPC_WAIT        0               /* wait flag */
 378 #define XPC_NOWAIT      1               /* no wait flag */
 379
 380
 381 struct xpc_interface {
 382         void (*connect)(int);
 383         void (*disconnect)(int);
 384         enum xpc_retval (*allocate)(partid_t, int, u32, void **);
 385         enum xpc_retval (*send)(partid_t, int, void *);
 386         enum xpc_retval (*send_notify)(partid_t, int, void *,
 387                                                 xpc_notify_func, void *);
 388         void (*received)(partid_t, int, void *);
 389         enum xpc_retval (*partid_to_nasids)(partid_t, void *);
 390 };
 391
 392
 393 extern struct xpc_interface xpc_interface;
 394
 395 extern void xpc_set_interface(void (*)(int),
 396                 void (*)(int),
 397                 enum xpc_retval (*)(partid_t, int, u32, void **),
 398                 enum xpc_retval (*)(partid_t, int, void *),
 399                 enum xpc_retval (*)(partid_t, int, void *, xpc_notify_func,
 400                                                                 void *),
 401                 void (*)(partid_t, int, void *),
 402                 enum xpc_retval (*)(partid_t, void *));
 403 extern void xpc_clear_interface(void);
 404
 405
 406 extern enum xpc_retval xpc_connect(int, xpc_channel_func, void *, u16,
 407                                                 u16, u32, u32);
 408 extern void xpc_disconnect(int);
 409
 410 static inline enum xpc_retval
 411 xpc_allocate(partid_t partid, int ch_number, u32 flags, void **payload)
 412 {
 413         return xpc_interface.allocate(partid, ch_number, flags, payload);
 414 }
 415
 416 static inline enum xpc_retval
 417 xpc_send(partid_t partid, int ch_number, void *payload)
 418 {
 419         return xpc_interface.send(partid, ch_number, payload);
 420 }
 421
 422 static inline enum xpc_retval
 423 xpc_send_notify(partid_t partid, int ch_number, void *payload,
 424                         xpc_notify_func func, void *key)
 425 {
 426         return xpc_interface.send_notify(partid, ch_number, payload, func, key);
 427 }
 428
 429 static inline void
 430 xpc_received(partid_t partid, int ch_number, void *payload)
 431 {
 432         return xpc_interface.received(partid, ch_number, payload);
 433 }
 434
 435 static inline enum xpc_retval
 436 xpc_partid_to_nasids(partid_t partid, void *nasids)
 437 {
 438         return xpc_interface.partid_to_nasids(partid, nasids);
 439 }
 440
 441
 442 extern u64 xp_nofault_PIOR_target;
 443 extern int xp_nofault_PIOR(void *);
 444 extern int xp_error_PIOR(void);
 445
 446
 447 #endif /* _ASM_IA64_SN_XP_H */
 448