drivers/staging/unisys/common-spar/include/channels/channel.h

   1 /* Copyright (C) 2010 - 2013 UNISYS CORPORATION
   2  * All rights reserved.
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License as published by
   6  * the Free Software Foundation; either version 2 of the License, or (at
   7  * your option) any later version.
   8  *
   9  * This program is distributed in the hope that it will be useful, but
  10  * WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
  12  * NON INFRINGEMENT.  See the GNU General Public License for more
  13  * details.
  14  */
  15
  16 #ifndef __CHANNEL_H__
  17 #define __CHANNEL_H__
  18
  19 #include <linux/uuid.h>
  20
  21 /*
  22 * Whenever this file is changed a corresponding change must be made in
  23 * the Console/ServicePart/visordiag_early/supervisor_channel.h file
  24 * which is needed for Linux kernel compiles. These two files must be
  25 * in sync.
  26 */
  27
  28 /* define the following to prevent include nesting in kernel header
  29  * files of similar abbreviated content
  30  */
  31 #define __SUPERVISOR_CHANNEL_H__
  32
  33 #include "commontypes.h"
  34
  35 #define SIGNATURE_16(A, B) ((A) | (B<<8))
  36 #define SIGNATURE_32(A, B, C, D) \
  37         (SIGNATURE_16(A, B) | (SIGNATURE_16(C, D) << 16))
  38 #define SIGNATURE_64(A, B, C, D, E, F, G, H) \
  39         (SIGNATURE_32(A, B, C, D) | ((u64)(SIGNATURE_32(E, F, G, H)) << 32))
  40
  41 #ifndef lengthof
  42 #define lengthof(TYPE, MEMBER) (sizeof(((TYPE *)0)->MEMBER))
  43 #endif
  44 #ifndef COVERQ
  45 #define COVERQ(v, d)  (((v)+(d)-1) / (d))
  46 #endif
  47 #ifndef COVER
  48 #define COVER(v, d)   ((d)*COVERQ(v, d))
  49 #endif
  50
  51 #define ULTRA_CHANNEL_PROTOCOL_SIGNATURE  SIGNATURE_32('E', 'C', 'N', 'L')
  52
  53 typedef enum {
  54         CHANNELSRV_UNINITIALIZED = 0,   /* channel is in an undefined state */
  55         CHANNELSRV_READY = 1    /* channel has been initialized by server */
  56 } CHANNEL_SERVERSTATE;
  57
  58 typedef enum {
  59         CHANNELCLI_DETACHED = 0,
  60         CHANNELCLI_DISABLED = 1,        /* client can see channel but is NOT
  61                                          * allowed to use it unless given TBD
  62                                          * explicit request (should actually be
  63                                          * < DETACHED) */
  64         CHANNELCLI_ATTACHING = 2,       /* legacy EFI client request
  65                                          * for EFI server to attach */
  66         CHANNELCLI_ATTACHED = 3,        /* idle, but client may want
  67                                          * to use channel any time */
  68         CHANNELCLI_BUSY = 4,    /* client either wants to use or is
  69                                  * using channel */
  70         CHANNELCLI_OWNED = 5    /* "no worries" state - client can
  71                                  * access channel anytime */
  72 } CHANNEL_CLIENTSTATE;
  73 static inline const u8 *
  74 ULTRA_CHANNELCLI_STRING(u32 v)
  75 {
  76         switch (v) {
  77         case CHANNELCLI_DETACHED:
  78                 return (const u8 *) ("DETACHED");
  79         case CHANNELCLI_DISABLED:
  80                 return (const u8 *) ("DISABLED");
  81         case CHANNELCLI_ATTACHING:
  82                 return (const u8 *) ("ATTACHING");
  83         case CHANNELCLI_ATTACHED:
  84                 return (const u8 *) ("ATTACHED");
  85         case CHANNELCLI_BUSY:
  86                 return (const u8 *) ("BUSY");
  87         case CHANNELCLI_OWNED:
  88                 return (const u8 *) ("OWNED");
  89         default:
  90                 break;
  91         }
  92         return (const u8 *) ("?");
  93 }
  94
  95 #define ULTRA_CHANNELSRV_IS_READY(x)     ((x) == CHANNELSRV_READY)
  96 #define ULTRA_CHANNEL_SERVER_READY(pChannel) \
  97         (ULTRA_CHANNELSRV_IS_READY(readl(&(pChannel)->SrvState)))
  98
  99 #define ULTRA_VALID_CHANNELCLI_TRANSITION(o, n)                         \
 100         (((((o) == CHANNELCLI_DETACHED) && ((n) == CHANNELCLI_DISABLED)) || \
 101           (((o) == CHANNELCLI_ATTACHING) && ((n) == CHANNELCLI_DISABLED)) || \
 102           (((o) == CHANNELCLI_ATTACHED) && ((n) == CHANNELCLI_DISABLED)) || \
 103           (((o) == CHANNELCLI_ATTACHING) && ((n) == CHANNELCLI_DETACHED)) || \
 104           (((o) == CHANNELCLI_ATTACHED) && ((n) == CHANNELCLI_DETACHED)) || \
 105           (((o) == CHANNELCLI_DETACHED) && ((n) == CHANNELCLI_ATTACHING)) || \
 106           (((o) == CHANNELCLI_ATTACHING) && ((n) == CHANNELCLI_ATTACHED)) || \
 107           (((o) == CHANNELCLI_DETACHED) && ((n) == CHANNELCLI_ATTACHED)) || \
 108           (((o) == CHANNELCLI_BUSY) && ((n) == CHANNELCLI_ATTACHED)) || \
 109           (((o) == CHANNELCLI_ATTACHED) && ((n) == CHANNELCLI_BUSY)) || \
 110           (((o) == CHANNELCLI_DETACHED) && ((n) == CHANNELCLI_OWNED)) || \
 111           (((o) == CHANNELCLI_DISABLED) && ((n) == CHANNELCLI_OWNED)) || \
 112           (((o) == CHANNELCLI_ATTACHING) && ((n) == CHANNELCLI_OWNED)) || \
 113           (((o) == CHANNELCLI_ATTACHED) && ((n) == CHANNELCLI_OWNED)) || \
 114           (((o) == CHANNELCLI_BUSY) && ((n) == CHANNELCLI_OWNED)) || (0)) \
 115          ? (1) : (0))
 116
 117 #define ULTRA_CHANNEL_CLIENT_CHK_TRANSITION(old, new, chanId, logCtx,   \
 118                                             file, line)                 \
 119         do {                                                            \
 120                 if (!ULTRA_VALID_CHANNELCLI_TRANSITION(old, new))       \
 121                         UltraLogEvent(logCtx,                           \
 122                                       CHANNELSTATE_DIAG_EVENTID_TRANSITERR, \
 123                                       CHANNELSTATE_DIAG_SEVERITY, \
 124                                       CHANNELSTATE_DIAG_SUBSYS,         \
 125                                       __func__, __LINE__,               \
 126                                       "%s Channel StateTransition INVALID! (%s) %s(%d)-->%s(%d) @%s:%d\n", \
 127                                       chanId, "CliState<x>",            \
 128                                       ULTRA_CHANNELCLI_STRING(old),     \
 129                                       old,                              \
 130                                       ULTRA_CHANNELCLI_STRING(new),     \
 131                                       new,                              \
 132                                       PathName_Last_N_Nodes((u8 *)file, 4), \
 133                                       line);                            \
 134         } while (0)
 135
 136 #define ULTRA_CHANNEL_CLIENT_TRANSITION(pChan, chanId,                  \
 137                                         newstate, logCtx)               \
 138         do {                                                            \
 139                 ULTRA_CHANNEL_CLIENT_CHK_TRANSITION(                    \
 140                         readl(&(((CHANNEL_HEADER __iomem *) \
 141                                  (pChan))->CliStateOS)),                \
 142                         newstate,                                       \
 143                         chanId, logCtx, __FILE__, __LINE__);            \
 144                 UltraLogEvent(logCtx, CHANNELSTATE_DIAG_EVENTID_TRANSITOK, \
 145                         CHANNELSTATE_DIAG_SEVERITY, \
 146                               CHANNELSTATE_DIAG_SUBSYS,                 \
 147                               __func__, __LINE__,                       \
 148                               "%s Channel StateTransition (%s) %s(%d)-->%s(%d) @%s:%d\n", \
 149                               chanId, "CliStateOS",                     \
 150                               ULTRA_CHANNELCLI_STRING( \
 151                                       readl(&((CHANNEL_HEADER __iomem *) \
 152                                               (pChan))->CliStateOS)),   \
 153                               readl(&((CHANNEL_HEADER __iomem *) \
 154                                       (pChan))->CliStateOS),            \
 155                               ULTRA_CHANNELCLI_STRING(newstate),        \
 156                               newstate,                                 \
 157                               PathName_Last_N_Nodes(__FILE__, 4), __LINE__); \
 158                 writel(newstate, &((CHANNEL_HEADER __iomem *) \
 159                                    (pChan))->CliStateOS);               \
 160                 MEMORYBARRIER;                                          \
 161         } while (0)
 162
 163 #define ULTRA_CHANNEL_CLIENT_ACQUIRE_OS(pChan, chanId, logCtx)  \
 164         ULTRA_channel_client_acquire_os(pChan, chanId, logCtx,          \
 165                                         (char *)__FILE__, __LINE__,     \
 166                                         (char *)__func__)
 167 #define ULTRA_CHANNEL_CLIENT_RELEASE_OS(pChan, chanId, logCtx)  \
 168         ULTRA_channel_client_release_os(pChan, chanId, logCtx,  \
 169                 (char *)__FILE__, __LINE__, (char *)__func__)
 170
 171 /* Values for ULTRA_CHANNEL_PROTOCOL.CliErrorBoot: */
 172 /* throttling invalid boot channel statetransition error due to client
 173  * disabled */
 174 #define ULTRA_CLIERRORBOOT_THROTTLEMSG_DISABLED    0x01
 175
 176 /* throttling invalid boot channel statetransition error due to client
 177  * not attached */
 178 #define ULTRA_CLIERRORBOOT_THROTTLEMSG_NOTATTACHED 0x02
 179
 180 /* throttling invalid boot channel statetransition error due to busy channel */
 181 #define ULTRA_CLIERRORBOOT_THROTTLEMSG_BUSY        0x04
 182
 183 /* Values for ULTRA_CHANNEL_PROTOCOL.CliErrorOS: */
 184 /* throttling invalid guest OS channel statetransition error due to
 185  * client disabled */
 186 #define ULTRA_CLIERROROS_THROTTLEMSG_DISABLED      0x01
 187
 188 /* throttling invalid guest OS channel statetransition error due to
 189  * client not attached */
 190 #define ULTRA_CLIERROROS_THROTTLEMSG_NOTATTACHED   0x02
 191
 192 /* throttling invalid guest OS channel statetransition error due to
 193  * busy channel */
 194 #define ULTRA_CLIERROROS_THROTTLEMSG_BUSY          0x04
 195
 196 /* Values for ULTRA_CHANNEL_PROTOCOL.Features: This define exists so
 197 * that windows guest can look at the FeatureFlags in the io channel,
 198 * and configure the windows driver to use interrupts or not based on
 199 * this setting.  This flag is set in uislib after the
 200 * ULTRA_VHBA_init_channel is called.  All feature bits for all
 201 * channels should be defined here.  The io channel feature bits are
 202 * defined right here */
 203 #define ULTRA_IO_DRIVER_ENABLES_INTS (0x1ULL << 1)
 204 #define ULTRA_IO_CHANNEL_IS_POLLING (0x1ULL << 3)
 205 #define ULTRA_IO_IOVM_IS_OK_WITH_DRIVER_DISABLING_INTS (0x1ULL << 4)
 206 #define ULTRA_IO_DRIVER_DISABLES_INTS (0x1ULL << 5)
 207 #define ULTRA_IO_DRIVER_SUPPORTS_ENHANCED_RCVBUF_CHECKING (0x1ULL << 6)
 208
 209 #pragma pack(push, 1)           /* both GCC and VC now allow this pragma */
 210 /* Common Channel Header */
 211 typedef struct _CHANNEL_HEADER {
 212         u64 Signature;          /* Signature */
 213         u32 LegacyState;        /* DEPRECATED - being replaced by */
 214         /* /              SrvState, CliStateBoot, and CliStateOS below */
 215         u32 HeaderSize;         /* sizeof(CHANNEL_HEADER) */
 216         u64 Size;               /* Total size of this channel in bytes */
 217         u64 Features;           /* Flags to modify behavior */
 218         uuid_le Type;           /* Channel type: data, bus, control, etc. */
 219         u64 PartitionHandle;    /* ID of guest partition */
 220         u64 Handle;             /* Device number of this channel in client */
 221         u64 oChannelSpace;      /* Offset in bytes to channel specific area */
 222         u32 VersionId;          /* CHANNEL_HEADER Version ID */
 223         u32 PartitionIndex;     /* Index of guest partition */
 224         uuid_le ZoneGuid;               /* Guid of Channel's zone */
 225         u32 oClientString;      /* offset from channel header to
 226                                  * nul-terminated ClientString (0 if
 227                                  * ClientString not present) */
 228         u32 CliStateBoot;       /* CHANNEL_CLIENTSTATE of pre-boot
 229                                  * EFI client of this channel */
 230         u32 CmdStateCli;        /* CHANNEL_COMMANDSTATE (overloaded in
 231                                  * Windows drivers, see ServerStateUp,
 232                                  * ServerStateDown, etc) */
 233         u32 CliStateOS;         /* CHANNEL_CLIENTSTATE of Guest OS
 234                                  * client of this channel */
 235         u32 ChannelCharacteristics;     /* CHANNEL_CHARACTERISTIC_<xxx> */
 236         u32 CmdStateSrv;        /* CHANNEL_COMMANDSTATE (overloaded in
 237                                  * Windows drivers, see ServerStateUp,
 238                                  * ServerStateDown, etc) */
 239         u32 SrvState;           /* CHANNEL_SERVERSTATE */
 240         u8 CliErrorBoot;        /* bits to indicate err states for
 241                                  * boot clients, so err messages can
 242                                  * be throttled */
 243         u8 CliErrorOS;          /* bits to indicate err states for OS
 244                                  * clients, so err messages can be
 245                                  * throttled */
 246         u8 Filler[1];           /* Pad out to 128 byte cacheline */
 247         /* Please add all new single-byte values below here */
 248         u8 RecoverChannel;
 249 } CHANNEL_HEADER, *pCHANNEL_HEADER, ULTRA_CHANNEL_PROTOCOL;
 250
 251 #define ULTRA_CHANNEL_ENABLE_INTS (0x1ULL << 0)
 252
 253 /* Subheader for the Signal Type variation of the Common Channel */
 254 typedef struct _SIGNAL_QUEUE_HEADER {
 255         /* 1st cache line */
 256         u32 VersionId;          /* SIGNAL_QUEUE_HEADER Version ID */
 257         u32 Type;               /* Queue type: storage, network */
 258         u64 Size;               /* Total size of this queue in bytes */
 259         u64 oSignalBase;        /* Offset to signal queue area */
 260         u64 FeatureFlags;       /* Flags to modify behavior */
 261         u64 NumSignalsSent;     /* Total # of signals placed in this queue */
 262         u64 NumOverflows;       /* Total # of inserts failed due to
 263                                  * full queue */
 264         u32 SignalSize;         /* Total size of a signal for this queue */
 265         u32 MaxSignalSlots;     /* Max # of slots in queue, 1 slot is
 266                                  * always empty */
 267         u32 MaxSignals;         /* Max # of signals in queue
 268                                  * (MaxSignalSlots-1) */
 269         u32 Head;               /* Queue head signal # */
 270         /* 2nd cache line */
 271         u64 NumSignalsReceived; /* Total # of signals removed from this queue */
 272         u32 Tail;               /* Queue tail signal # (on separate
 273                                  * cache line) */
 274         u32 Reserved1;          /* Reserved field */
 275         u64 Reserved2;          /* Resrved field */
 276         u64 ClientQueue;
 277         u64 NumInterruptsReceived;      /* Total # of Interrupts received.  This
 278                                          * is incremented by the ISR in the
 279                                          * guest windows driver */
 280         u64 NumEmptyCnt;        /* Number of times that visor_signal_remove
 281                                  * is called and returned Empty
 282                                  * Status. */
 283         u32 ErrorFlags;         /* Error bits set during SignalReinit
 284                                  * to denote trouble with client's
 285                                  * fields */
 286         u8 Filler[12];          /* Pad out to 64 byte cacheline */
 287 } SIGNAL_QUEUE_HEADER, *pSIGNAL_QUEUE_HEADER;
 288
 289 #pragma pack(pop)
 290
 291 #define SignalInit(chan, QHDRFLD, QDATAFLD, QDATATYPE, ver, typ)        \
 292         do {                                                            \
 293                 memset(&chan->QHDRFLD, 0, sizeof(chan->QHDRFLD));       \
 294                 chan->QHDRFLD.VersionId = ver;                          \
 295                 chan->QHDRFLD.Type = typ;                               \
 296                 chan->QHDRFLD.Size = sizeof(chan->QDATAFLD);            \
 297                 chan->QHDRFLD.SignalSize = sizeof(QDATATYPE);           \
 298                 chan->QHDRFLD.oSignalBase = (u64)(chan->QDATAFLD)-      \
 299                         (u64)(&chan->QHDRFLD);                          \
 300                 chan->QHDRFLD.MaxSignalSlots =                          \
 301                         sizeof(chan->QDATAFLD)/sizeof(QDATATYPE);       \
 302                 chan->QHDRFLD.MaxSignals = chan->QHDRFLD.MaxSignalSlots-1; \
 303         } while (0)
 304
 305 /* Generic function useful for validating any type of channel when it is
 306  * received by the client that will be accessing the channel.
 307  * Note that <logCtx> is only needed for callers in the EFI environment, and
 308  * is used to pass the EFI_DIAG_CAPTURE_PROTOCOL needed to log messages.
 309  */
 310 static inline int
 311 ULTRA_check_channel_client(void __iomem *pChannel,
 312                            uuid_le expectedTypeGuid,
 313                            char *channelName,
 314                            u64 expectedMinBytes,
 315                            u32 expectedVersionId,
 316                            u64 expectedSignature,
 317                            char *fileName, int lineNumber, void *logCtx)
 318 {
 319         if (uuid_le_cmp(expectedTypeGuid, NULL_UUID_LE) != 0)
 320                 /* caller wants us to verify type GUID */
 321                 if (uuid_le_cmp((((CHANNEL_HEADER __iomem *)(pChannel))->Type),
 322                            expectedTypeGuid) != 0) {
 323                         CHANNEL_GUID_MISMATCH(expectedTypeGuid, channelName,
 324                                               "type", expectedTypeGuid,
 325                                               ((CHANNEL_HEADER __iomem *)
 326                                                (pChannel))->Type, fileName,
 327                                               lineNumber, logCtx);
 328                         return 0;
 329                 }
 330         if (expectedMinBytes > 0)       /* caller wants us to verify
 331                                          * channel size */
 332                 if (readq(&((CHANNEL_HEADER __iomem *)
 333                            (pChannel))->Size) < expectedMinBytes) {
 334                         CHANNEL_U64_MISMATCH(expectedTypeGuid, channelName,
 335                                              "size", expectedMinBytes,
 336                                              readq(&((CHANNEL_HEADER __iomem *)
 337                                                      (pChannel))->Size),
 338                                              fileName,
 339                                              lineNumber, logCtx);
 340                         return 0;
 341                 }
 342         if (expectedVersionId > 0)      /* caller wants us to verify
 343                                          * channel version */
 344                 if (readl(&((CHANNEL_HEADER __iomem *) (pChannel))->VersionId)
 345                     != expectedVersionId) {
 346                         CHANNEL_U32_MISMATCH(expectedTypeGuid, channelName,
 347                                              "version", expectedVersionId,
 348                                              readl(&((CHANNEL_HEADER __iomem *)
 349                                                      (pChannel))->VersionId),
 350                                              fileName, lineNumber, logCtx);
 351                         return 0;
 352                 }
 353         if (expectedSignature > 0)      /* caller wants us to verify
 354                                          * channel signature */
 355                 if (readq(&((CHANNEL_HEADER __iomem *) (pChannel))->Signature)
 356                     != expectedSignature) {
 357                         CHANNEL_U64_MISMATCH(expectedTypeGuid, channelName,
 358                                              "signature", expectedSignature,
 359                                              readq(&((CHANNEL_HEADER __iomem *)
 360                                                      (pChannel))->Signature),
 361                                              fileName,
 362                                              lineNumber, logCtx);
 363                         return 0;
 364                 }
 365         return 1;
 366 }
 367
 368 /* Generic function useful for validating any type of channel when it is about
 369  * to be initialized by the server of the channel.
 370  * Note that <logCtx> is only needed for callers in the EFI environment, and
 371  * is used to pass the EFI_DIAG_CAPTURE_PROTOCOL needed to log messages.
 372  */
 373 static inline int
 374 ULTRA_check_channel_server(uuid_le typeGuid,
 375                            char *channelName,
 376                            u64 expectedMinBytes,
 377                            u64 actualBytes,
 378                            char *fileName, int lineNumber, void *logCtx)
 379 {
 380         if (expectedMinBytes > 0)       /* caller wants us to verify
 381                                          * channel size */
 382                 if (actualBytes < expectedMinBytes) {
 383                         CHANNEL_U64_MISMATCH(typeGuid, channelName, "size",
 384                                              expectedMinBytes, actualBytes,
 385                                              fileName, lineNumber, logCtx);
 386                         return 0;
 387                 }
 388         return 1;
 389 }
 390
 391 /* Given a file pathname <s> (with '/' or '\' separating directory nodes),
 392  * returns a pointer to the beginning of a node within that pathname such
 393  * that the number of nodes from that pointer to the end of the string is
 394  * NOT more than <n>.  Note that if the pathname has less than <n> nodes
 395  * in it, the return pointer will be to the beginning of the string.
 396  */
 397 static inline u8 *
 398 PathName_Last_N_Nodes(u8 *s, unsigned int n)
 399 {
 400         u8 *p = s;
 401         unsigned int node_count = 0;
 402         while (*p != '\0') {
 403                 if ((*p == '/') || (*p == '\\'))
 404                         node_count++;
 405                 p++;
 406         }
 407         if (node_count <= n)
 408                 return s;
 409         while (n > 0) {
 410                 p--;
 411                 if (p == s)
 412                         break;  /* should never happen, unless someone
 413                                  * is changing the string while we are
 414                                  * looking at it!! */
 415                 if ((*p == '/') || (*p == '\\'))
 416                         n--;
 417         }
 418         return p + 1;
 419 }
 420
 421 static inline int
 422 ULTRA_channel_client_acquire_os(void __iomem *pChannel, u8 *chanId,
 423                                 void *logCtx, char *file, int line, char *func)
 424 {
 425         CHANNEL_HEADER __iomem *pChan = pChannel;
 426
 427         if (readl(&pChan->CliStateOS) == CHANNELCLI_DISABLED) {
 428                 if ((readb(&pChan->CliErrorOS)
 429                      & ULTRA_CLIERROROS_THROTTLEMSG_DISABLED) == 0) {
 430                         /* we are NOT throttling this message */
 431                         writeb(readb(&pChan->CliErrorOS) |
 432                                ULTRA_CLIERROROS_THROTTLEMSG_DISABLED,
 433                                &pChan->CliErrorOS);
 434                         /* throttle until acquire successful */
 435
 436                         UltraLogEvent(logCtx,
 437                                       CHANNELSTATE_DIAG_EVENTID_TRANSITERR,
 438                                       CHANNELSTATE_DIAG_SEVERITY,
 439                                       CHANNELSTATE_DIAG_SUBSYS, func, line,
 440                                       "%s Channel StateTransition INVALID! - acquire failed because OS client DISABLED @%s:%d\n",
 441                                       chanId, PathName_Last_N_Nodes(
 442                                               (u8 *) file, 4), line);
 443                 }
 444                 return 0;
 445         }
 446         if ((readl(&pChan->CliStateOS) != CHANNELCLI_OWNED)
 447             && (readl(&pChan->CliStateBoot) == CHANNELCLI_DISABLED)) {
 448                 /* Our competitor is DISABLED, so we can transition to OWNED */
 449                 UltraLogEvent(logCtx, CHANNELSTATE_DIAG_EVENTID_TRANSITOK,
 450                               CHANNELSTATE_DIAG_SEVERITY,
 451                               CHANNELSTATE_DIAG_SUBSYS, func, line,
 452                               "%s Channel StateTransition (%s) %s(%d)-->%s(%d) @%s:%d\n",
 453                               chanId, "CliStateOS",
 454                               ULTRA_CHANNELCLI_STRING(
 455                                       readl(&pChan->CliStateOS)),
 456                               readl(&pChan->CliStateOS),
 457                               ULTRA_CHANNELCLI_STRING(CHANNELCLI_OWNED),
 458                               CHANNELCLI_OWNED,
 459                               PathName_Last_N_Nodes((u8 *) file, 4), line);
 460                 writel(CHANNELCLI_OWNED, &pChan->CliStateOS);
 461                 MEMORYBARRIER;
 462         }
 463         if (readl(&pChan->CliStateOS) == CHANNELCLI_OWNED) {
 464                 if (readb(&pChan->CliErrorOS) != 0) {
 465                         /* we are in an error msg throttling state;
 466                          * come out of it */
 467                         UltraLogEvent(logCtx,
 468                                       CHANNELSTATE_DIAG_EVENTID_TRANSITOK,
 469                                       CHANNELSTATE_DIAG_SEVERITY,
 470                                       CHANNELSTATE_DIAG_SUBSYS, func, line,
 471                                       "%s Channel OS client acquire now successful @%s:%d\n",
 472                                       chanId, PathName_Last_N_Nodes((u8 *) file,
 473                                                                     4), line);
 474                         writeb(0, &pChan->CliErrorOS);
 475                 }
 476                 return 1;
 477         }
 478
 479         /* We have to do it the "hard way".  We transition to BUSY,
 480         * and can use the channel iff our competitor has not also
 481         * transitioned to BUSY. */
 482         if (readl(&pChan->CliStateOS) != CHANNELCLI_ATTACHED) {
 483                 if ((readb(&pChan->CliErrorOS)
 484                      & ULTRA_CLIERROROS_THROTTLEMSG_NOTATTACHED) == 0) {
 485                         /* we are NOT throttling this message */
 486                         writeb(readb(&pChan->CliErrorOS) |
 487                                ULTRA_CLIERROROS_THROTTLEMSG_NOTATTACHED,
 488                                &pChan->CliErrorOS);
 489                         /* throttle until acquire successful */
 490                         UltraLogEvent(logCtx,
 491                                       CHANNELSTATE_DIAG_EVENTID_TRANSITERR,
 492                                       CHANNELSTATE_DIAG_SEVERITY,
 493                                       CHANNELSTATE_DIAG_SUBSYS, func, line,
 494                                       "%s Channel StateTransition INVALID! - acquire failed because OS client NOT ATTACHED (state=%s(%d)) @%s:%d\n",
 495                                       chanId,
 496                                       ULTRA_CHANNELCLI_STRING(
 497                                               readl(&pChan->CliStateOS)),
 498                                       readl(&pChan->CliStateOS),
 499                                       PathName_Last_N_Nodes((u8 *) file, 4),
 500                                       line);
 501                 }
 502                 return 0;
 503         }
 504         writel(CHANNELCLI_BUSY, &pChan->CliStateOS);
 505         MEMORYBARRIER;
 506         if (readl(&pChan->CliStateBoot) == CHANNELCLI_BUSY) {
 507                 if ((readb(&pChan->CliErrorOS)
 508                      & ULTRA_CLIERROROS_THROTTLEMSG_BUSY) == 0) {
 509                         /* we are NOT throttling this message */
 510                         writeb(readb(&pChan->CliErrorOS) |
 511                                ULTRA_CLIERROROS_THROTTLEMSG_BUSY,
 512                                &pChan->CliErrorOS);
 513                         /* throttle until acquire successful */
 514                         UltraLogEvent(logCtx,
 515                                       CHANNELSTATE_DIAG_EVENTID_TRANSITBUSY,
 516                                       CHANNELSTATE_DIAG_SEVERITY,
 517                                       CHANNELSTATE_DIAG_SUBSYS, func, line,
 518                                       "%s Channel StateTransition failed - host OS acquire failed because boot BUSY @%s:%d\n",
 519                                       chanId, PathName_Last_N_Nodes((u8 *) file,
 520                                                                     4), line);
 521                 }
 522                 /* reset busy */
 523                 writel(CHANNELCLI_ATTACHED, &pChan->CliStateOS);
 524                 MEMORYBARRIER;
 525                 return 0;
 526         }
 527         if (readb(&pChan->CliErrorOS) != 0) {
 528                 /* we are in an error msg throttling state; come out of it */
 529                 UltraLogEvent(logCtx, CHANNELSTATE_DIAG_EVENTID_TRANSITOK,
 530                               CHANNELSTATE_DIAG_SEVERITY,
 531                               CHANNELSTATE_DIAG_SUBSYS, func, line,
 532                               "%s Channel OS client acquire now successful @%s:%d\n",
 533                               chanId, PathName_Last_N_Nodes((u8 *) file, 4),
 534                               line);
 535                 writeb(0, &pChan->CliErrorOS);
 536         }
 537         return 1;
 538 }
 539
 540 static inline void
 541 ULTRA_channel_client_release_os(void __iomem *pChannel, u8 *chanId,
 542                                 void *logCtx, char *file, int line, char *func)
 543 {
 544         CHANNEL_HEADER __iomem *pChan = pChannel;
 545         if (readb(&pChan->CliErrorOS) != 0) {
 546                 /* we are in an error msg throttling state; come out of it */
 547                 UltraLogEvent(logCtx, CHANNELSTATE_DIAG_EVENTID_TRANSITOK,
 548                               CHANNELSTATE_DIAG_SEVERITY,
 549                               CHANNELSTATE_DIAG_SUBSYS, func, line,
 550                               "%s Channel OS client error state cleared @%s:%d\n",
 551                               chanId, PathName_Last_N_Nodes((u8 *) file, 4),
 552                               line);
 553                 writeb(0, &pChan->CliErrorOS);
 554         }
 555         if (readl(&pChan->CliStateOS) == CHANNELCLI_OWNED)
 556                 return;
 557         if (readl(&pChan->CliStateOS) != CHANNELCLI_BUSY) {
 558                 UltraLogEvent(logCtx, CHANNELSTATE_DIAG_EVENTID_TRANSITERR,
 559                               CHANNELSTATE_DIAG_SEVERITY,
 560                               CHANNELSTATE_DIAG_SUBSYS, func, line,
 561                               "%s Channel StateTransition INVALID! - release failed because OS client NOT BUSY (state=%s(%d)) @%s:%d\n",
 562                               chanId,
 563                               ULTRA_CHANNELCLI_STRING(
 564                                       readl(&pChan->CliStateOS)),
 565                               readl(&pChan->CliStateOS),
 566                               PathName_Last_N_Nodes((u8 *) file, 4), line);
 567                 /* return; */
 568         }
 569         writel(CHANNELCLI_ATTACHED, &pChan->CliStateOS); /* release busy */
 570 }
 571
 572 /*
 573 * Routine Description:
 574 * Tries to insert the prebuilt signal pointed to by pSignal into the nth
 575 * Queue of the Channel pointed to by pChannel
 576 *
 577 * Parameters:
 578 * pChannel: (IN) points to the IO Channel
 579 * Queue: (IN) nth Queue of the IO Channel
 580 * pSignal: (IN) pointer to the signal
 581 *
 582 * Assumptions:
 583 * - pChannel, Queue and pSignal are valid.
 584 * - If insertion fails due to a full queue, the caller will determine the
 585 * retry policy (e.g. wait & try again, report an error, etc.).
 586 *
 587 * Return value: 1 if the insertion succeeds, 0 if the queue was
 588 * full.
 589 */
 590
 591 unsigned char visor_signal_insert(CHANNEL_HEADER __iomem *pChannel, u32 Queue,
 592                                   void *pSignal);
 593
 594 /*
 595 * Routine Description:
 596 * Removes one signal from Channel pChannel's nth Queue at the
 597 * time of the call and copies it into the memory pointed to by
 598 * pSignal.
 599 *
 600 * Parameters:
 601 * pChannel: (IN) points to the IO Channel
 602 * Queue: (IN) nth Queue of the IO Channel
 603 * pSignal: (IN) pointer to where the signals are to be copied
 604 *
 605 * Assumptions:
 606 * - pChannel and Queue are valid.
 607 * - pSignal points to a memory area large enough to hold queue's SignalSize
 608 *
 609 * Return value: 1 if the removal succeeds, 0 if the queue was
 610 * empty.
 611 */
 612
 613 unsigned char visor_signal_remove(CHANNEL_HEADER __iomem *pChannel, u32 Queue,
 614                                   void *pSignal);
 615
 616 /*
 617 * Routine Description:
 618 * Removes all signals present in Channel pChannel's nth Queue at the
 619 * time of the call and copies them into the memory pointed to by
 620 * pSignal.  Returns the # of signals copied as the value of the routine.
 621 *
 622 * Parameters:
 623 * pChannel: (IN) points to the IO Channel
 624 * Queue: (IN) nth Queue of the IO Channel
 625 * pSignal: (IN) pointer to where the signals are to be copied
 626 *
 627 * Assumptions:
 628 * - pChannel and Queue are valid.
 629 * - pSignal points to a memory area large enough to hold Queue's MaxSignals
 630 * # of signals, each of which is Queue's SignalSize.
 631 *
 632 * Return value:
 633 * # of signals copied.
 634 */
 635 unsigned int SignalRemoveAll(pCHANNEL_HEADER pChannel, u32 Queue,
 636                              void *pSignal);
 637
 638 /*
 639 * Routine Description:
 640 * Determine whether a signal queue is empty.
 641 *
 642 * Parameters:
 643 * pChannel: (IN) points to the IO Channel
 644 * Queue: (IN) nth Queue of the IO Channel
 645 *
 646 * Return value:
 647 * 1 if the signal queue is empty, 0 otherwise.
 648 */
 649 unsigned char visor_signalqueue_empty(CHANNEL_HEADER __iomem *pChannel,
 650                                       u32 Queue);
 651
 652 #endif