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  *      src - physical address of the source of the transfer.
  64  *      vdst - virtual address of the destination of the transfer.
  65  *      len - number of bytes to transfer from source to destination.
  66  *      mode - see bte_copy() for definition.
  67  *      notification - see bte_copy() for definition.
  68  *
  69  * Note: xp_bte_copy() should never be called while holding a spinlock.
  70  */
  71 static inline bte_result_t
  72 xp_bte_copy(u64 src, u64 vdst, u64 len, u64 mode, void *notification)
  73 {
  74         bte_result_t ret;
  75         u64 pdst = ia64_tpa(vdst);
  76
  77
  78         /*
  79          * Ensure that the physically mapped memory is contiguous.
  80          *
  81          * We do this by ensuring that the memory is from region 7 only.
  82          * If the need should arise to use memory from one of the other
  83          * regions, then modify the BUG_ON() statement to ensure that the
  84          * memory from that region is always physically contiguous.
  85          */
  86         BUG_ON(REGION_NUMBER(vdst) != RGN_KERNEL);
  87
  88         ret = bte_copy(src, pdst, len, mode, notification);
  89         if (ret != BTE_SUCCESS) {
  90                 if (!in_interrupt()) {
  91                         cond_resched();
  92                 }
  93                 ret = bte_copy(src, pdst, len, mode, notification);
  94         }
  95
  96         return ret;
  97 }
  98
  99
 100 /*
 101  * XPC establishes channel connections between the local partition and any
 102  * other partition that is currently up. Over these channels, kernel-level
 103  * `users' can communicate with their counterparts on the other partitions.
 104  *
 105  * The maxinum number of channels is limited to eight. For performance reasons,
 106  * the internal cross partition structures require sixteen bytes per channel,
 107  * and eight allows all of this interface-shared info to fit in one cache line.
 108  *
 109  * XPC_NCHANNELS reflects the total number of channels currently defined.
 110  * If the need for additional channels arises, one can simply increase
 111  * XPC_NCHANNELS accordingly. If the day should come where that number
 112  * exceeds the MAXIMUM number of channels allowed (eight), then one will need
 113  * to make changes to the XPC code to allow for this.
 114  */
 115 #define XPC_MEM_CHANNEL         0       /* memory channel number */
 116 #define XPC_NET_CHANNEL         1       /* network channel number */
 117
 118 #define XPC_NCHANNELS           2       /* #of defined channels */
 119 #define XPC_MAX_NCHANNELS       8       /* max #of channels allowed */
 120
 121 #if XPC_NCHANNELS > XPC_MAX_NCHANNELS
 122 #error  XPC_NCHANNELS exceeds MAXIMUM allowed.
 123 #endif
 124
 125
 126 /*
 127  * The format of an XPC message is as follows:
 128  *
 129  *      +-------+--------------------------------+
 130  *      | flags |////////////////////////////////|
 131  *      +-------+--------------------------------+
 132  *      |             message #                  |
 133  *      +----------------------------------------+
 134  *      |     payload (user-defined message)     |
 135  *      |                                        |
 136  *                      :
 137  *      |                                        |
 138  *      +----------------------------------------+
 139  *
 140  * The size of the payload is defined by the user via xpc_connect(). A user-
 141  * defined message resides in the payload area.
 142  *
 143  * The user should have no dealings with the message header, but only the
 144  * message's payload. When a message entry is allocated (via xpc_allocate())
 145  * a pointer to the payload area is returned and not the actual beginning of
 146  * the XPC message. The user then constructs a message in the payload area
 147  * and passes that pointer as an argument on xpc_send() or xpc_send_notify().
 148  *
 149  * The size of a message entry (within a message queue) must be a cacheline
 150  * sized multiple in order to facilitate the BTE transfer of messages from one
 151  * message queue to another. A macro, XPC_MSG_SIZE(), is provided for the user
 152  * that wants to fit as many msg entries as possible in a given memory size
 153  * (e.g. a memory page).
 154  */
 155 struct xpc_msg {
 156         u8 flags;               /* FOR XPC INTERNAL USE ONLY */
 157         u8 reserved[7];         /* FOR XPC INTERNAL USE ONLY */
 158         s64 number;             /* FOR XPC INTERNAL USE ONLY */
 159
 160         u64 payload;            /* user defined portion of message */
 161 };
 162
 163
 164 #define XPC_MSG_PAYLOAD_OFFSET  (u64) (&((struct xpc_msg *)0)->payload)
 165 #define XPC_MSG_SIZE(_payload_size) \
 166                 L1_CACHE_ALIGN(XPC_MSG_PAYLOAD_OFFSET + (_payload_size))
 167
 168
 169 /*
 170  * Define the return values and values passed to user's callout functions.
 171  * (It is important to add new value codes at the end just preceding
 172  * xpcUnknownReason, which must have the highest numerical value.)
 173  */
 174 enum xpc_retval {
 175         xpcSuccess = 0,
 176
 177         xpcNotConnected,        /*  1: channel is not connected */
 178         xpcConnected,           /*  2: channel connected (opened) */
 179         xpcRETIRED1,            /*  3: (formerly xpcDisconnected) */
 180
 181         xpcMsgReceived,         /*  4: message received */
 182         xpcMsgDelivered,        /*  5: message delivered and acknowledged */
 183
 184         xpcRETIRED2,            /*  6: (formerly xpcTransferFailed) */
 185
 186         xpcNoWait,              /*  7: operation would require wait */
 187         xpcRetry,               /*  8: retry operation */
 188         xpcTimeout,             /*  9: timeout in xpc_allocate_msg_wait() */
 189         xpcInterrupted,         /* 10: interrupted wait */
 190
 191         xpcUnequalMsgSizes,     /* 11: message size disparity between sides */
 192         xpcInvalidAddress,      /* 12: invalid address */
 193
 194         xpcNoMemory,            /* 13: no memory available for XPC structures */
 195         xpcLackOfResources,     /* 14: insufficient resources for operation */
 196         xpcUnregistered,        /* 15: channel is not registered */
 197         xpcAlreadyRegistered,   /* 16: channel is already registered */
 198
 199         xpcPartitionDown,       /* 17: remote partition is down */
 200         xpcNotLoaded,           /* 18: XPC module is not loaded */
 201         xpcUnloading,           /* 19: this side is unloading XPC module */
 202
 203         xpcBadMagic,            /* 20: XPC MAGIC string not found */
 204
 205         xpcReactivating,        /* 21: remote partition was reactivated */
 206
 207         xpcUnregistering,       /* 22: this side is unregistering channel */
 208         xpcOtherUnregistering,  /* 23: other side is unregistering channel */
 209
 210         xpcCloneKThread,        /* 24: cloning kernel thread */
 211         xpcCloneKThreadFailed,  /* 25: cloning kernel thread failed */
 212
 213         xpcNoHeartbeat,         /* 26: remote partition has no heartbeat */
 214
 215         xpcPioReadError,        /* 27: PIO read error */
 216         xpcPhysAddrRegFailed,   /* 28: registration of phys addr range failed */
 217
 218         xpcBteDirectoryError,   /* 29: maps to BTEFAIL_DIR */
 219         xpcBtePoisonError,      /* 30: maps to BTEFAIL_POISON */
 220         xpcBteWriteError,       /* 31: maps to BTEFAIL_WERR */
 221         xpcBteAccessError,      /* 32: maps to BTEFAIL_ACCESS */
 222         xpcBtePWriteError,      /* 33: maps to BTEFAIL_PWERR */
 223         xpcBtePReadError,       /* 34: maps to BTEFAIL_PRERR */
 224         xpcBteTimeOutError,     /* 35: maps to BTEFAIL_TOUT */
 225         xpcBteXtalkError,       /* 36: maps to BTEFAIL_XTERR */
 226         xpcBteNotAvailable,     /* 37: maps to BTEFAIL_NOTAVAIL */
 227         xpcBteUnmappedError,    /* 38: unmapped BTEFAIL_ error */
 228
 229         xpcBadVersion,          /* 39: bad version number */
 230         xpcVarsNotSet,          /* 40: the XPC variables are not set up */
 231         xpcNoRsvdPageAddr,      /* 41: unable to get rsvd page's phys addr */
 232         xpcInvalidPartid,       /* 42: invalid partition ID */
 233         xpcLocalPartid,         /* 43: local partition ID */
 234
 235         xpcOtherGoingDown,      /* 44: other side going down, reason unknown */
 236         xpcSystemGoingDown,     /* 45: system is going down, reason unknown */
 237         xpcSystemHalt,          /* 46: system is being halted */
 238         xpcSystemReboot,        /* 47: system is being rebooted */
 239         xpcSystemPoweroff,      /* 48: system is being powered off */
 240
 241         xpcDisconnecting,       /* 49: channel disconnecting (closing) */
 242
 243         xpcOpenCloseError,      /* 50: channel open/close protocol error */
 244
 245         xpcDisconnected,        /* 51: channel disconnected (closed) */
 246
 247         xpcUnknownReason        /* 52: unknown reason -- must be last in list */
 248 };
 249
 250
 251 /*
 252  * Define the callout function types used by XPC to update the user on
 253  * connection activity and state changes (via the user function registered by
 254  * xpc_connect()) and to notify them of messages received and delivered (via
 255  * the user function registered by xpc_send_notify()).
 256  *
 257  * The two function types are xpc_channel_func and xpc_notify_func and
 258  * both share the following arguments, with the exception of "data", which
 259  * only xpc_channel_func has.
 260  *
 261  * Arguments:
 262  *
 263  *      reason - reason code. (See following table.)
 264  *      partid - partition ID associated with condition.
 265  *      ch_number - channel # associated with condition.
 266  *      data - pointer to optional data. (See following table.)
 267  *      key - pointer to optional user-defined value provided as the "key"
 268  *            argument to xpc_connect() or xpc_send_notify().
 269  *
 270  * In the following table the "Optional Data" column applies to callouts made
 271  * to functions registered by xpc_connect(). A "NA" in that column indicates
 272  * that this reason code can be passed to functions registered by
 273  * xpc_send_notify() (i.e. they don't have data arguments).
 274  *
 275  * Also, the first three reason codes in the following table indicate
 276  * success, whereas the others indicate failure. When a failure reason code
 277  * is received, one can assume that the channel is not connected.
 278  *
 279  *
 280  * Reason Code          | Cause                          | Optional Data
 281  * =====================+================================+=====================
 282  * xpcConnected         | connection has been established| max #of entries
 283  *                      | to the specified partition on  | allowed in message
 284  *                      | the specified channel          | queue
 285  * ---------------------+--------------------------------+---------------------
 286  * xpcMsgReceived       | an XPC message arrived from    | address of payload
 287  *                      | the specified partition on the |
 288  *                      | specified channel              | [the user must call
 289  *                      |                                | xpc_received() when
 290  *                      |                                | finished with the
 291  *                      |                                | payload]
 292  * ---------------------+--------------------------------+---------------------
 293  * xpcMsgDelivered      | notification that the message  | NA
 294  *                      | was delivered to the intended  |
 295  *                      | recipient and that they have   |
 296  *                      | acknowledged its receipt by    |
 297  *                      | calling xpc_received()         |
 298  * =====================+================================+=====================
 299  * xpcUnequalMsgSizes   | can't connect to the specified | NULL
 300  *                      | partition on the specified     |
 301  *                      | channel because of mismatched  |
 302  *                      | message sizes                  |
 303  * ---------------------+--------------------------------+---------------------
 304  * xpcNoMemory          | insufficient memory avaiable   | NULL
 305  *                      | to allocate message queue      |
 306  * ---------------------+--------------------------------+---------------------
 307  * xpcLackOfResources   | lack of resources to create    | NULL
 308  *                      | the necessary kthreads to      |
 309  *                      | support the channel            |
 310  * ---------------------+--------------------------------+---------------------
 311  * xpcUnregistering     | this side's user has           | NULL or NA
 312  *                      | unregistered by calling        |
 313  *                      | xpc_disconnect()               |
 314  * ---------------------+--------------------------------+---------------------
 315  * xpcOtherUnregistering| the other side's user has      | NULL or NA
 316  *                      | unregistered by calling        |
 317  *                      | xpc_disconnect()               |
 318  * ---------------------+--------------------------------+---------------------
 319  * xpcNoHeartbeat       | the other side's XPC is no     | NULL or NA
 320  *                      | longer heartbeating            |
 321  *                      |                                |
 322  * ---------------------+--------------------------------+---------------------
 323  * xpcUnloading         | this side's XPC module is      | NULL or NA
 324  *                      | being unloaded                 |
 325  *                      |                                |
 326  * ---------------------+--------------------------------+---------------------
 327  * xpcOtherUnloading    | the other side's XPC module is | NULL or NA
 328  *                      | is being unloaded              |
 329  *                      |                                |
 330  * ---------------------+--------------------------------+---------------------
 331  * xpcPioReadError      | xp_nofault_PIOR() returned an  | NULL or NA
 332  *                      | error while sending an IPI     |
 333  *                      |                                |
 334  * ---------------------+--------------------------------+---------------------
 335  * xpcInvalidAddress    | the address either received or | NULL or NA
 336  *                      | sent by the specified partition|
 337  *                      | is invalid                     |
 338  * ---------------------+--------------------------------+---------------------
 339  * xpcBteNotAvailable   | attempt to pull data from the  | NULL or NA
 340  * xpcBtePoisonError    | specified partition over the   |
 341  * xpcBteWriteError     | specified channel via a        |
 342  * xpcBteAccessError    | bte_copy() failed              |
 343  * xpcBteTimeOutError   |                                |
 344  * xpcBteXtalkError     |                                |
 345  * xpcBteDirectoryError |                                |
 346  * xpcBteGenericError   |                                |
 347  * xpcBteUnmappedError  |                                |
 348  * ---------------------+--------------------------------+---------------------
 349  * xpcUnknownReason     | the specified channel to the   | NULL or NA
 350  *                      | specified partition was        |
 351  *                      | unavailable for unknown reasons|
 352  * =====================+================================+=====================
 353  */
 354
 355 typedef void (*xpc_channel_func)(enum xpc_retval reason, partid_t partid,
 356                 int ch_number, void *data, void *key);
 357
 358 typedef void (*xpc_notify_func)(enum xpc_retval reason, partid_t partid,
 359                 int ch_number, void *key);
 360
 361
 362 /*
 363  * The following is a registration entry. There is a global array of these,
 364  * one per channel. It is used to record the connection registration made
 365  * by the users of XPC. As long as a registration entry exists, for any
 366  * partition that comes up, XPC will attempt to establish a connection on
 367  * that channel. Notification that a connection has been made will occur via
 368  * the xpc_channel_func function.
 369  *
 370  * The 'func' field points to the function to call when aynchronous
 371  * notification is required for such events as: a connection established/lost,
 372  * or an incoming message received, or an error condition encountered. A
 373  * non-NULL 'func' field indicates that there is an active registration for
 374  * the channel.
 375  */
 376 struct xpc_registration {
 377         struct mutex mutex;
 378         xpc_channel_func func;          /* function to call */
 379         void *key;                      /* pointer to user's key */
 380         u16 nentries;                   /* #of msg entries in local msg queue */
 381         u16 msg_size;                   /* message queue's message size */
 382         u32 assigned_limit;             /* limit on #of assigned kthreads */
 383         u32 idle_limit;                 /* limit on #of idle kthreads */
 384 } ____cacheline_aligned;
 385
 386
 387 #define XPC_CHANNEL_REGISTERED(_c)      (xpc_registrations[_c].func != NULL)
 388
 389
 390 /* the following are valid xpc_allocate() flags */
 391 #define XPC_WAIT        0               /* wait flag */
 392 #define XPC_NOWAIT      1               /* no wait flag */
 393
 394
 395 struct xpc_interface {
 396         void (*connect)(int);
 397         void (*disconnect)(int);
 398         enum xpc_retval (*allocate)(partid_t, int, u32, void **);
 399         enum xpc_retval (*send)(partid_t, int, void *);
 400         enum xpc_retval (*send_notify)(partid_t, int, void *,
 401                                                 xpc_notify_func, void *);
 402         void (*received)(partid_t, int, void *);
 403         enum xpc_retval (*partid_to_nasids)(partid_t, void *);
 404 };
 405
 406
 407 extern struct xpc_interface xpc_interface;
 408
 409 extern void xpc_set_interface(void (*)(int),
 410                 void (*)(int),
 411                 enum xpc_retval (*)(partid_t, int, u32, void **),
 412                 enum xpc_retval (*)(partid_t, int, void *),
 413                 enum xpc_retval (*)(partid_t, int, void *, xpc_notify_func,
 414                                                                 void *),
 415                 void (*)(partid_t, int, void *),
 416                 enum xpc_retval (*)(partid_t, void *));
 417 extern void xpc_clear_interface(void);
 418
 419
 420 extern enum xpc_retval xpc_connect(int, xpc_channel_func, void *, u16,
 421                                                 u16, u32, u32);
 422 extern void xpc_disconnect(int);
 423
 424 static inline enum xpc_retval
 425 xpc_allocate(partid_t partid, int ch_number, u32 flags, void **payload)
 426 {
 427         return xpc_interface.allocate(partid, ch_number, flags, payload);
 428 }
 429
 430 static inline enum xpc_retval
 431 xpc_send(partid_t partid, int ch_number, void *payload)
 432 {
 433         return xpc_interface.send(partid, ch_number, payload);
 434 }
 435
 436 static inline enum xpc_retval
 437 xpc_send_notify(partid_t partid, int ch_number, void *payload,
 438                         xpc_notify_func func, void *key)
 439 {
 440         return xpc_interface.send_notify(partid, ch_number, payload, func, key);
 441 }
 442
 443 static inline void
 444 xpc_received(partid_t partid, int ch_number, void *payload)
 445 {
 446         return xpc_interface.received(partid, ch_number, payload);
 447 }
 448
 449 static inline enum xpc_retval
 450 xpc_partid_to_nasids(partid_t partid, void *nasids)
 451 {
 452         return xpc_interface.partid_to_nasids(partid, nasids);
 453 }
 454
 455
 456 extern u64 xp_nofault_PIOR_target;
 457 extern int xp_nofault_PIOR(void *);
 458 extern int xp_error_PIOR(void);
 459
 460
 461 #endif /* _ASM_IA64_SN_XP_H */
 462