git.oblomov.eu Git - linux-2.6/blob - drivers/staging/epl/ShbIpc-LinuxKernel.c

   1 /****************************************************************************
   2
   3   (c) SYSTEC electronic GmbH, D-07973 Greiz, August-Bebel-Str. 29
   4       www.systec-electronic.com
   5
   6   Project:      Project independend shared buffer (linear + circular)
   7
   8   Description:  Implementation of platform specific part for the
   9                 shared buffer
  10                 (Implementation for Linux KernelSpace)
  11
  12   License:
  13
  14     Redistribution and use in source and binary forms, with or without
  15     modification, are permitted provided that the following conditions
  16     are met:
  17
  18     1. Redistributions of source code must retain the above copyright
  19        notice, this list of conditions and the following disclaimer.
  20
  21     2. Redistributions in binary form must reproduce the above copyright
  22        notice, this list of conditions and the following disclaimer in the
  23        documentation and/or other materials provided with the distribution.
  24
  25     3. Neither the name of SYSTEC electronic GmbH nor the names of its
  26        contributors may be used to endorse or promote products derived
  27        from this software without prior written permission. For written
  28        permission, please contact info@systec-electronic.com.
  29
  30     THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  31     "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  32     LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
  33     FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
  34     COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
  35     INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
  36     BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  37     LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
  38     CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  39     LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
  40     ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  41     POSSIBILITY OF SUCH DAMAGE.
  42
  43     Severability Clause:
  44
  45         If a provision of this License is or becomes illegal, invalid or
  46         unenforceable in any jurisdiction, that shall not affect:
  47         1. the validity or enforceability in that jurisdiction of any other
  48            provision of this License; or
  49         2. the validity or enforceability in other jurisdictions of that or
  50            any other provision of this License.
  51
  52   -------------------------------------------------------------------------
  53
  54   2006/06/28 -rs:   V 1.00 (initial version)
  55
  56 ****************************************************************************/
  57
  58 #include "global.h"
  59 #include "SharedBuff.h"
  60 #include "ShbIpc.h"
  61 #include "ShbLinuxKernel.h"
  62 #include "Debug.h"
  63
  64 #include <linux/string.h>
  65 #include <linux/module.h>
  66 #include <asm/processor.h>
  67 //#include <linux/vmalloc.h>
  68 #include <linux/sched.h>
  69 #include <linux/param.h>
  70 #include <linux/spinlock.h>
  71 #include <linux/wait.h>
  72 #include <linux/completion.h>
  73
  74 /***************************************************************************/
  75 /*                                                                         */
  76 /*                                                                         */
  77 /*          G L O B A L   D E F I N I T I O N S                            */
  78 /*                                                                         */
  79 /*                                                                         */
  80 /***************************************************************************/
  81
  82 //---------------------------------------------------------------------------
  83 //  Configuration
  84 //---------------------------------------------------------------------------
  85
  86 //---------------------------------------------------------------------------
  87 //  Constant definitions
  88 //---------------------------------------------------------------------------
  89
  90 #define MAX_LEN_BUFFER_ID       256
  91
  92 #define TIMEOUT_ENTER_ATOMIC    1000    // (ms) for debgging: INFINITE
  93 #define TIMEOUT_TERM_THREAD     1000
  94 #define INFINITE                3600
  95
  96 #define SBI_MAGIC_ID            0x5342492B      // magic ID ("SBI+")
  97 #define SBH_MAGIC_ID            0x5342482A      // magic ID ("SBH*")
  98
  99 #define INVALID_ID              -1
 100
 101 #define TABLE_SIZE              10
 102
 103 //---------------------------------------------------------------------------
 104 //  Local types
 105 //---------------------------------------------------------------------------
 106
 107 // This structure is the common header for the shared memory region used
 108 // by all processes attached this shared memory. It includes common
 109 // information to administrate/manage the shared buffer from a couple of
 110 // separated processes (e.g. the refernce counter). This structure is
 111 // located at the start of the shared memory region itself and exists
 112 // consequently only one times per shared memory instance.
 113 typedef struct {
 114
 115         unsigned long m_ulShMemSize;
 116         unsigned long m_ulRefCount;
 117         int m_iBufferId;
 118 //    int                 m_iUserSpaceMem;           //0 for userspace mem   !=0 kernelspace mem
 119         spinlock_t m_SpinlockBuffAccess;
 120         BOOL m_fNewData;
 121         BOOL m_fJobReady;
 122         wait_queue_head_t m_WaitQueueNewData;
 123         wait_queue_head_t m_WaitQueueJobReady;
 124
 125 #ifndef NDEBUG
 126         unsigned long m_ulOwnerProcID;
 127 #endif
 128
 129 } tShbMemHeader;
 130
 131 // This structure is the "external entry point" from a separate process
 132 // to get access to a shared buffer. This structure includes all platform
 133 // resp. target specific information to administrate/manage the shared
 134 // buffer from a separate process. Every process attached to the shared
 135 // buffer has its own runtime instance of this structure with its individual
 136 // runtime data (e.g. the scope of an event handle is limitted to the
 137 // owner process only). The structure member <m_pShbMemHeader> points
 138 // to the (process specific) start address of the shared memory region
 139 // itself.
 140 typedef struct {
 141         unsigned long m_SbiMagicID;     // magic ID ("SBI+")
 142 //    void*               m_pSharedMem;
 143         int m_tThreadNewDataId;
 144         long m_lThreadNewDataNice;      // nice value of the new data thread
 145         int m_tThreadJobReadyId;
 146         unsigned long m_ulFlagsBuffAccess;      // d.k. moved from tShbMemHeader, because each
 147         // process needs to store the interrupt flags separately
 148         tSigHndlrNewData m_pfnSigHndlrNewData;
 149         unsigned long m_ulTimeOutJobReady;
 150         tSigHndlrJobReady m_pfnSigHndlrJobReady;
 151         tShbMemHeader *m_pShbMemHeader;
 152         int m_iThreadTermFlag;
 153         struct completion m_CompletionNewData;
 154 /*
 155     struct semaphore    *m_pSemBuffAccess;
 156     struct semaphore    *m_pSemNewData;
 157     struct semaphore    *m_pSemStopSignalingNewData;
 158     struct semaphore    *m_pSemJobReady;
 159 */
 160 #ifndef NDEBUG
 161         unsigned long m_ulThreadIDNewData;
 162         unsigned long m_ulThreadIDJobReady;
 163 #endif
 164 } tShbMemInst;
 165
 166 //---------------------------------------------------------------------------
 167 //  Prototypes of internal functions
 168 //---------------------------------------------------------------------------
 169
 170 //tShbMemInst*            ShbIpcGetShbMemInst         (tShbInstance pShbInstance_p);
 171 //tShbMemHeader*          ShbIpcGetShbMemHeader       (tShbMemInst* pShbMemInst_p);
 172
 173 //---------------------------------------------------------------------------
 174 //  Get pointer to process local information structure
 175 //---------------------------------------------------------------------------
 176
 177 static inline tShbMemInst *ShbIpcGetShbMemInst(tShbInstance pShbInstance_p)
 178 {
 179
 180         tShbMemInst *pShbMemInst;
 181
 182         pShbMemInst = (tShbMemInst *) pShbInstance_p;
 183
 184         return (pShbMemInst);
 185
 186 }
 187
 188 //---------------------------------------------------------------------------
 189 //  Get pointer to shared memory header
 190 //---------------------------------------------------------------------------
 191
 192 static inline tShbMemHeader *ShbIpcGetShbMemHeader(tShbMemInst * pShbMemInst_p)
 193 {
 194
 195         tShbMemHeader *pShbMemHeader;
 196
 197         pShbMemHeader = pShbMemInst_p->m_pShbMemHeader;
 198
 199         return (pShbMemHeader);
 200
 201 }
 202
 203 //  Get pointer to process local information structure
 204 //#define ShbIpcGetShbMemInst(pShbInstance_p) ((tShbMemInst*)pShbInstance_p)
 205
 206 //  Get pointer to shared memory header
 207 //#define ShbIpcGetShbMemHeader(pShbMemInst_p) (pShbMemInst_p->m_pShbMemHeader)
 208
 209 // not inlined internal functions
 210 int ShbIpcThreadSignalNewData(void *pvThreadParam_p);
 211 int ShbIpcThreadSignalJobReady(void *pvThreadParam_p);
 212
 213 //---------------------------------------------------------------------------
 214 // modul globale vars
 215 //---------------------------------------------------------------------------
 216
 217 struct sShbMemTable *psMemTableElementFirst_g;
 218
 219 static void *ShbIpcAllocPrivateMem(unsigned long ulMemSize_p);
 220 static int ShbIpcFindListElement(int iBufferId,
 221                                  struct sShbMemTable
 222                                  **ppsReturnMemTableElement);
 223 static void ShbIpcAppendListElement(struct sShbMemTable *sNewMemTableElement);
 224 static void ShbIpcDeleteListElement(int iBufferId);
 225 static void ShbIpcCrc32GenTable(unsigned long aulCrcTable[256]);
 226 static unsigned long ShbIpcCrc32GetCrc(const char *pcString,
 227                                        unsigned long aulCrcTable[256]);
 228
 229
 230 //=========================================================================//
 231 //                                                                         //
 232 //          P U B L I C   F U N C T I O N S                                //
 233 //                                                                         //
 234 //=========================================================================//
 235
 236 // not inlined external functions
 237
 238 //---------------------------------------------------------------------------
 239 //  Initialize IPC for Shared Buffer Module
 240 //---------------------------------------------------------------------------
 241
 242 tShbError ShbIpcInit(void)
 243 {
 244         psMemTableElementFirst_g = NULL;
 245         return (kShbOk);
 246
 247 }
 248
 249 //---------------------------------------------------------------------------
 250 //  Deinitialize IPC for Shared Buffer Module
 251 //---------------------------------------------------------------------------
 252
 253 tShbError ShbIpcExit(void)
 254 {
 255
 256         return (kShbOk);
 257
 258 }
 259
 260 //---------------------------------------------------------------------------
 261 //  Allocate Shared Buffer
 262 //---------------------------------------------------------------------------
 263
 264 tShbError ShbIpcAllocBuffer(unsigned long ulBufferSize_p,
 265                             const char *pszBufferID_p,
 266                             tShbInstance * ppShbInstance_p,
 267                             unsigned int *pfShbNewCreated_p)
 268 {
 269         tShbError ShbError;
 270         int iBufferId = 0;
 271         unsigned long ulCrc32 = 0;
 272         unsigned int uiFirstProcess = 0;
 273         unsigned long ulShMemSize;
 274         tShbMemHeader *pShbMemHeader;
 275         tShbMemInst *pShbMemInst = NULL;
 276         tShbInstance pShbInstance;
 277         unsigned int fShMemNewCreated = FALSE;
 278         void *pSharedMem = NULL;
 279         unsigned long aulCrcTable[256];
 280         struct sShbMemTable *psMemTableElement;
 281
 282         DEBUG_LVL_29_TRACE0("ShbIpcAllocBuffer \n");
 283         ulShMemSize = ulBufferSize_p + sizeof(tShbMemHeader);
 284
 285         //create Buffer ID
 286         ShbIpcCrc32GenTable(aulCrcTable);
 287         ulCrc32 = ShbIpcCrc32GetCrc(pszBufferID_p, aulCrcTable);
 288         iBufferId = ulCrc32;
 289         DEBUG_LVL_29_TRACE2
 290             ("ShbIpcAllocBuffer BufferSize:%d sizeof(tShb..):%d\n",
 291              ulBufferSize_p, sizeof(tShbMemHeader));
 292         DEBUG_LVL_29_TRACE2("ShbIpcAllocBuffer BufferId:%d MemSize:%d\n",
 293                             iBufferId, ulShMemSize);
 294         //---------------------------------------------------------------
 295         // (1) open an existing or create a new shared memory
 296         //---------------------------------------------------------------
 297         //test if buffer already exists
 298         if (ShbIpcFindListElement(iBufferId, &psMemTableElement) == 0) {
 299                 //Buffer already exists
 300                 fShMemNewCreated = FALSE;
 301                 pSharedMem = psMemTableElement->m_pBuffer;
 302                 DEBUG_LVL_29_TRACE1
 303                     ("ShbIpcAllocBuffer attach Buffer at:%p Id:%d\n",
 304                      pSharedMem);
 305                 uiFirstProcess = 1;
 306         } else {
 307                 //create new Buffer
 308                 fShMemNewCreated = TRUE;
 309                 uiFirstProcess = 0;
 310                 pSharedMem = kmalloc(ulShMemSize, GFP_KERNEL);
 311                 DEBUG_LVL_29_TRACE2
 312                     ("ShbIpcAllocBuffer Create New Buffer at:%p Id:%d\n",
 313                      pSharedMem, iBufferId);
 314                 if (pSharedMem == NULL) {
 315                         //unable to create mem
 316                         ShbError = kShbOutOfMem;
 317                         goto Exit;
 318                 }
 319                 DEBUG_LVL_29_TRACE0("ShbIpcAllocBuffer create semas\n");
 320                 // append Element to Mem Table
 321                 psMemTableElement =
 322                     kmalloc(sizeof(struct sShbMemTable), GFP_KERNEL);
 323                 psMemTableElement->m_iBufferId = iBufferId;
 324                 psMemTableElement->m_pBuffer = pSharedMem;
 325                 psMemTableElement->m_psNextMemTableElement = NULL;
 326                 ShbIpcAppendListElement(psMemTableElement);
 327         }
 328
 329         DEBUG_LVL_29_TRACE0("ShbIpcAllocBuffer update header\n");
 330         //update header
 331         pShbMemHeader = (tShbMemHeader *) pSharedMem;
 332         DEBUG_LVL_29_TRACE1
 333             ("ShbIpcAllocBuffer 0 pShbMemHeader->m_ulShMemSize: %d\n",
 334              pShbMemHeader->m_ulShMemSize);
 335         // allocate a memory block from process specific mempool to save
 336         // process local information to administrate/manage the shared buffer
 337         DEBUG_LVL_29_TRACE0("ShbIpcAllocBuffer alloc private mem\n");
 338         pShbMemInst =
 339             (tShbMemInst *) ShbIpcAllocPrivateMem(sizeof(tShbMemInst));
 340         if (pShbMemInst == NULL) {
 341                 ShbError = kShbOutOfMem;
 342                 goto Exit;
 343         }
 344         // reset complete header to default values
 345         //pShbMemInst->m_SbiMagicID                             = SBI_MAGIC_ID;
 346 //    pShbMemInst->m_pSharedMem                               = pSharedMem;
 347         pShbMemInst->m_tThreadNewDataId = INVALID_ID;
 348         pShbMemInst->m_tThreadJobReadyId = INVALID_ID;
 349         pShbMemInst->m_pfnSigHndlrNewData = NULL;
 350         pShbMemInst->m_ulTimeOutJobReady = 0;
 351         pShbMemInst->m_pfnSigHndlrJobReady = NULL;
 352         pShbMemInst->m_pShbMemHeader = pShbMemHeader;
 353         pShbMemInst->m_iThreadTermFlag = 0;
 354
 355         // initialize completion etc.
 356         init_completion(&pShbMemInst->m_CompletionNewData);
 357
 358         ShbError = kShbOk;
 359         if (fShMemNewCreated) {
 360                 // this process was the first who wanted to use the shared memory,
 361                 // so a new shared memory was created
 362                 // -> setup new header information inside the shared memory region
 363                 //    itself
 364                 pShbMemHeader->m_ulShMemSize = ulShMemSize;
 365                 pShbMemHeader->m_ulRefCount = 1;
 366                 pShbMemHeader->m_iBufferId = iBufferId;
 367                 // initialize spinlock
 368                 spin_lock_init(&pShbMemHeader->m_SpinlockBuffAccess);
 369                 // initialize wait queues
 370                 init_waitqueue_head(&pShbMemHeader->m_WaitQueueNewData);
 371                 init_waitqueue_head(&pShbMemHeader->m_WaitQueueJobReady);
 372         } else {
 373                 // any other process has created the shared memory and this
 374                 // process only has to attach to it
 375                 // -> check and update existing header information inside the
 376                 //    shared memory region itself
 377                 if (pShbMemHeader->m_ulShMemSize != ulShMemSize) {
 378                         ShbError = kShbOpenMismatch;
 379                         goto Exit;
 380                 }
 381                 pShbMemHeader->m_ulRefCount++;
 382         }
 383
 384       Exit:
 385         pShbInstance = (tShbInstance *) pShbMemInst;
 386         *pfShbNewCreated_p = fShMemNewCreated;
 387         *ppShbInstance_p = pShbInstance;
 388         return (ShbError);
 389
 390 }
 391
 392 //---------------------------------------------------------------------------
 393 //  Release Shared Buffer
 394 //---------------------------------------------------------------------------
 395
 396 tShbError ShbIpcReleaseBuffer(tShbInstance pShbInstance_p)
 397 {
 398         tShbMemInst *pShbMemInst;
 399         tShbMemHeader *pShbMemHeader;
 400         tShbError ShbError;
 401         tShbError ShbError2;
 402
 403         DEBUG_LVL_26_TRACE1("ShbIpcReleaseBuffer(%p)\n", pShbInstance_p);
 404         if (pShbInstance_p == NULL) {
 405                 return (kShbOk);
 406         }
 407         pShbMemInst = ShbIpcGetShbMemInst(pShbInstance_p);
 408         pShbMemHeader = ShbIpcGetShbMemHeader(pShbMemInst);
 409
 410         // stop threads in any case, because they are bound to that specific instance
 411         ShbError2 = ShbIpcStopSignalingNewData(pShbInstance_p);
 412         // d.k.: Whats up with JobReady thread?
 413         //       Just wake it up, but without setting the semaphore variable
 414         wake_up_interruptible(&pShbMemHeader->m_WaitQueueJobReady);
 415
 416         if (!--pShbMemHeader->m_ulRefCount) {
 417                 ShbError = kShbOk;
 418                 // delete mem table element
 419                 ShbIpcDeleteListElement(pShbMemHeader->m_iBufferId);
 420                 // delete shared mem
 421                 kfree(pShbMemInst->m_pShbMemHeader);
 422         } else {
 423                 ShbError = kShbMemUsedByOtherProcs;
 424         }
 425         //delete privat mem
 426         kfree(pShbMemInst);
 427         return (ShbError);
 428 }
 429
 430 //---------------------------------------------------------------------------
 431 //  Enter atomic section for Shared Buffer access
 432 //---------------------------------------------------------------------------
 433
 434 tShbError ShbIpcEnterAtomicSection(tShbInstance pShbInstance_p)
 435 {
 436
 437         tShbMemInst *pShbMemInst;
 438         tShbMemHeader *pShbMemHeader;
 439         tShbError ShbError = kShbOk;
 440
 441         if (pShbInstance_p == NULL) {
 442                 ShbError = kShbInvalidArg;
 443                 goto Exit;
 444         }
 445         DEBUG_LVL_29_TRACE0("enter atomic\n");
 446         pShbMemInst = ShbIpcGetShbMemInst(pShbInstance_p);
 447         pShbMemHeader = ShbIpcGetShbMemHeader(pShbMemInst);
 448
 449         // lock interrupts
 450         spin_lock_irqsave(&pShbMemHeader->m_SpinlockBuffAccess,
 451                           pShbMemInst->m_ulFlagsBuffAccess);
 452
 453       Exit:
 454         return ShbError;
 455
 456 }
 457
 458 //---------------------------------------------------------------------------
 459 //  Leave atomic section for Shared Buffer access
 460 //---------------------------------------------------------------------------
 461
 462 tShbError ShbIpcLeaveAtomicSection(tShbInstance pShbInstance_p)
 463 {
 464
 465         tShbMemInst *pShbMemInst;
 466         tShbMemHeader *pShbMemHeader;
 467         tShbError ShbError = kShbOk;
 468
 469         if (pShbInstance_p == NULL) {
 470                 ShbError = kShbInvalidArg;
 471                 goto Exit;
 472         }
 473         pShbMemInst = ShbIpcGetShbMemInst(pShbInstance_p);
 474         pShbMemHeader = ShbIpcGetShbMemHeader(pShbMemInst);
 475         // unlock interrupts
 476         spin_unlock_irqrestore(&pShbMemHeader->m_SpinlockBuffAccess,
 477                                pShbMemInst->m_ulFlagsBuffAccess);
 478
 479       Exit:
 480         DEBUG_LVL_29_TRACE0("Leave Atomic \n");
 481         return ShbError;
 482
 483 }
 484
 485 //---------------------------------------------------------------------------
 486 //  Start signaling of new data (called from reading process)
 487 //---------------------------------------------------------------------------
 488
 489 tShbError ShbIpcStartSignalingNewData(tShbInstance pShbInstance_p,
 490                                       tSigHndlrNewData pfnSignalHandlerNewData_p,
 491                                       tShbPriority ShbPriority_p)
 492 {
 493         tShbMemInst *pShbMemInst;
 494         tShbMemHeader *pShbMemHeader;
 495         tShbError ShbError;
 496
 497         DEBUG_LVL_29_TRACE0("------->ShbIpcStartSignalingNewData\n");
 498         if ((pShbInstance_p == NULL) || (pfnSignalHandlerNewData_p == NULL)) {
 499                 return (kShbInvalidArg);
 500         }
 501
 502         pShbMemInst = ShbIpcGetShbMemInst(pShbInstance_p);
 503         pShbMemHeader = ShbIpcGetShbMemHeader(pShbMemInst);
 504         ShbError = kShbOk;
 505
 506         if ((pShbMemInst->m_tThreadNewDataId != INVALID_ID)
 507             || (pShbMemInst->m_pfnSigHndlrNewData != NULL)) {
 508                 ShbError = kShbAlreadySignaling;
 509                 goto Exit;
 510         }
 511         DEBUG_LVL_26_TRACE2
 512             ("ShbIpcStartSignalingNewData(%p) m_pfnSigHndlrNewData = %p\n",
 513              pShbInstance_p, pfnSignalHandlerNewData_p);
 514         pShbMemInst->m_pfnSigHndlrNewData = pfnSignalHandlerNewData_p;
 515         pShbMemHeader->m_fNewData = FALSE;
 516         pShbMemInst->m_iThreadTermFlag = 0;
 517
 518         switch (ShbPriority_p) {
 519         case kShbPriorityLow:
 520                 pShbMemInst->m_lThreadNewDataNice = -2;
 521                 break;
 522
 523         case kShbPriorityNormal:
 524                 pShbMemInst->m_lThreadNewDataNice = -9;
 525                 break;
 526
 527         case kshbPriorityHigh:
 528                 pShbMemInst->m_lThreadNewDataNice = -20;
 529                 break;
 530
 531         }
 532
 533         //create thread for signalling new data
 534         pShbMemInst->m_tThreadNewDataId =
 535             kernel_thread(ShbIpcThreadSignalNewData, pShbInstance_p,
 536                           CLONE_KERNEL);
 537
 538       Exit:
 539         return ShbError;
 540
 541 }
 542
 543 //---------------------------------------------------------------------------
 544 //  Stop signaling of new data (called from reading process)
 545 //---------------------------------------------------------------------------
 546
 547 tShbError ShbIpcStopSignalingNewData(tShbInstance pShbInstance_p)
 548 {
 549         tShbMemInst *pShbMemInst;
 550         tShbMemHeader *pShbMemHeader;
 551         tShbError ShbError;
 552
 553         DEBUG_LVL_29_TRACE0("------->ShbIpcStopSignalingNewData\n");
 554         if (pShbInstance_p == NULL) {
 555                 return (kShbInvalidArg);
 556         }
 557         ShbError = kShbOk;
 558         pShbMemInst = ShbIpcGetShbMemInst(pShbInstance_p);
 559         pShbMemHeader = ShbIpcGetShbMemHeader(pShbMemInst);
 560
 561         DEBUG_LVL_26_TRACE2
 562             ("ShbIpcStopSignalingNewData(%p) pfnSignHndlrNewData=%p\n",
 563              pShbInstance_p, pShbMemInst->m_pfnSigHndlrNewData);
 564         if (pShbMemInst->m_pfnSigHndlrNewData != NULL) {        // signal handler was set before
 565                 int iErr;
 566                 //set termination flag in mem header
 567                 pShbMemInst->m_iThreadTermFlag = 1;
 568
 569                 // check if thread is still running at all by sending the null-signal to this thread
 570                 /* iErr = kill_proc(pShbMemInst->m_tThreadNewDataId, 0, 1); */
 571                 iErr = send_sig(0, pShbMemInst->m_tThreadNewDataId, 1);
 572                 if (iErr == 0) {
 573                         // wake up thread, because it is still running
 574                         wake_up_interruptible(&pShbMemHeader->
 575                                               m_WaitQueueNewData);
 576
 577                         //wait for termination of thread
 578                         wait_for_completion(&pShbMemInst->m_CompletionNewData);
 579                 }
 580
 581                 pShbMemInst->m_pfnSigHndlrNewData = NULL;
 582                 pShbMemInst->m_tThreadNewDataId = INVALID_ID;
 583         }
 584
 585         return ShbError;
 586
 587 }
 588
 589 //---------------------------------------------------------------------------
 590 //  Signal new data (called from writing process)
 591 //---------------------------------------------------------------------------
 592
 593 tShbError ShbIpcSignalNewData(tShbInstance pShbInstance_p)
 594 {
 595         tShbMemHeader *pShbMemHeader;
 596
 597         if (pShbInstance_p == NULL) {
 598                 return (kShbInvalidArg);
 599         }
 600         pShbMemHeader =
 601             ShbIpcGetShbMemHeader(ShbIpcGetShbMemInst(pShbInstance_p));
 602         //set semaphore
 603         pShbMemHeader->m_fNewData = TRUE;
 604         DEBUG_LVL_29_TRACE0("ShbIpcSignalNewData set Sem -> New Data\n");
 605
 606         wake_up_interruptible(&pShbMemHeader->m_WaitQueueNewData);
 607         return (kShbOk);
 608 }
 609
 610 //---------------------------------------------------------------------------
 611 //  Start signaling for job ready (called from waiting process)
 612 //---------------------------------------------------------------------------
 613
 614 tShbError ShbIpcStartSignalingJobReady(tShbInstance pShbInstance_p,
 615                                        unsigned long ulTimeOut_p,
 616                                        tSigHndlrJobReady pfnSignalHandlerJobReady_p)
 617 {
 618         tShbMemInst *pShbMemInst;
 619         tShbMemHeader *pShbMemHeader;
 620         tShbError ShbError;
 621
 622         if ((pShbInstance_p == NULL) || (pfnSignalHandlerJobReady_p == NULL)) {
 623                 return (kShbInvalidArg);
 624         }
 625         pShbMemInst = ShbIpcGetShbMemInst(pShbInstance_p);
 626         pShbMemHeader = ShbIpcGetShbMemHeader(pShbMemInst);
 627
 628         ShbError = kShbOk;
 629         if ((pShbMemInst->m_tThreadJobReadyId != INVALID_ID)
 630             || (pShbMemInst->m_pfnSigHndlrJobReady != NULL)) {
 631                 ShbError = kShbAlreadySignaling;
 632                 goto Exit;
 633         }
 634         pShbMemInst->m_ulTimeOutJobReady = ulTimeOut_p;
 635         pShbMemInst->m_pfnSigHndlrJobReady = pfnSignalHandlerJobReady_p;
 636         pShbMemHeader->m_fJobReady = FALSE;
 637         //create thread for signalling new data
 638         pShbMemInst->m_tThreadJobReadyId =
 639             kernel_thread(ShbIpcThreadSignalJobReady, pShbInstance_p,
 640                           CLONE_KERNEL);
 641       Exit:
 642         return ShbError;
 643 }
 644
 645 //---------------------------------------------------------------------------
 646 //  Signal job ready (called from executing process)
 647 //---------------------------------------------------------------------------
 648
 649 tShbError ShbIpcSignalJobReady(tShbInstance pShbInstance_p)
 650 {
 651         tShbMemHeader *pShbMemHeader;
 652
 653         DEBUG_LVL_29_TRACE0("ShbIpcSignalJobReady\n");
 654         if (pShbInstance_p == NULL) {
 655                 return (kShbInvalidArg);
 656         }
 657         pShbMemHeader =
 658             ShbIpcGetShbMemHeader(ShbIpcGetShbMemInst(pShbInstance_p));
 659         //set semaphore
 660         pShbMemHeader->m_fJobReady = TRUE;
 661         DEBUG_LVL_29_TRACE0("ShbIpcSignalJobReady set Sem -> Job Ready \n");
 662
 663         wake_up_interruptible(&pShbMemHeader->m_WaitQueueJobReady);
 664         return (kShbOk);
 665 }
 666
 667 //---------------------------------------------------------------------------
 668 //  Get pointer to common used share memory area
 669 //---------------------------------------------------------------------------
 670
 671 void *ShbIpcGetShMemPtr(tShbInstance pShbInstance_p)
 672 {
 673
 674         tShbMemHeader *pShbMemHeader;
 675         void *pShbShMemPtr;
 676
 677         pShbMemHeader =
 678             ShbIpcGetShbMemHeader(ShbIpcGetShbMemInst(pShbInstance_p));
 679         if (pShbMemHeader != NULL) {
 680                 pShbShMemPtr = (u8 *) pShbMemHeader + sizeof(tShbMemHeader);
 681         } else {
 682                 pShbShMemPtr = NULL;
 683         }
 684
 685         return (pShbShMemPtr);
 686
 687 }
 688
 689 //=========================================================================//
 690 //                                                                         //
 691 //          P R I V A T E   F U N C T I O N S                              //
 692 //                                                                         //
 693 //=========================================================================//
 694
 695 //---------------------------------------------------------------------------
 696 //  Get pointer to process local information structure
 697 //---------------------------------------------------------------------------
 698
 699 /*tShbMemInst*  ShbIpcGetShbMemInst (
 700     tShbInstance pShbInstance_p)
 701 {
 702
 703 tShbMemInst*  pShbMemInst;
 704
 705     pShbMemInst = (tShbMemInst*)pShbInstance_p;
 706
 707     return (pShbMemInst);
 708
 709 }
 710 */
 711
 712 //---------------------------------------------------------------------------
 713 //  Get pointer to shared memory header
 714 //---------------------------------------------------------------------------
 715
 716 /*tShbMemHeader*  ShbIpcGetShbMemHeader (
 717     tShbMemInst* pShbMemInst_p)
 718 {
 719
 720 tShbMemHeader*  pShbMemHeader;
 721
 722     pShbMemHeader = pShbMemInst_p->m_pShbMemHeader;
 723
 724     return (pShbMemHeader);
 725
 726 }
 727 */
 728
 729 //---------------------------------------------------------------------------
 730 //  Allocate a memory block from process specific mempool
 731 //---------------------------------------------------------------------------
 732
 733 static void *ShbIpcAllocPrivateMem(unsigned long ulMemSize_p)
 734 {
 735         tShbError ShbError;
 736         void *pMem;
 737
 738         DEBUG_LVL_29_TRACE0("ShbIpcAllocPrivateMem \n");
 739         //get private mem
 740         pMem = kmalloc(ulMemSize_p, GFP_KERNEL);
 741         if (pMem == NULL) {
 742                 //unable to create mem
 743                 ShbError = kShbOutOfMem;
 744                 goto Exit;
 745         }
 746       Exit:
 747         return (pMem);
 748
 749 }
 750
 751 //---------------------------------------------------------------------------
 752 //  Thread for new data signaling
 753 //---------------------------------------------------------------------------
 754
 755 int ShbIpcThreadSignalNewData(void *pvThreadParam_p)
 756 {
 757         tShbInstance pShbInstance;
 758         tShbMemInst *pShbMemInst;
 759         tShbMemHeader *pShbMemHeader;
 760         int iRetVal = -1;
 761         int fCallAgain;
 762
 763         daemonize("ShbND%p", pvThreadParam_p);
 764         allow_signal(SIGTERM);
 765         pShbInstance = (tShbMemInst *) pvThreadParam_p;
 766         pShbMemInst = ShbIpcGetShbMemInst(pShbInstance);
 767         pShbMemHeader = ShbIpcGetShbMemHeader(pShbMemInst);
 768
 769         DEBUG_LVL_26_TRACE1("ShbIpcThreadSignalNewData(%p)\n", pvThreadParam_p);
 770
 771         set_user_nice(current, pShbMemInst->m_lThreadNewDataNice);
 772
 773 //            DEBUG_LVL_29_TRACE1("ShbIpcThreadSignalNewData wait for New Data Sem %p\n",pShbMemInst->m_pSemNewData);
 774         do {
 775                 iRetVal =
 776                     wait_event_interruptible(pShbMemHeader->m_WaitQueueNewData,
 777                                              (pShbMemInst->m_iThreadTermFlag !=
 778                                               0)
 779                                              || (pShbMemHeader->m_fNewData !=
 780                                                  FALSE));
 781
 782                 if (iRetVal != 0) {     // signal pending
 783                         break;
 784                 }
 785
 786                 if (pShbMemHeader->m_fNewData != FALSE) {
 787                         pShbMemHeader->m_fNewData = FALSE;
 788                         do {
 789                                 fCallAgain =
 790                                     pShbMemInst->
 791                                     m_pfnSigHndlrNewData(pShbInstance);
 792                                 // call scheduler, which will execute any task with higher priority
 793                                 schedule();
 794                         } while (fCallAgain != FALSE);
 795                 }
 796         } while (pShbMemInst->m_iThreadTermFlag == 0);
 797         DEBUG_LVL_29_TRACE0("ShbIpcThreadSignalNewData terminated \n");
 798         //set thread completed
 799         complete_and_exit(&pShbMemInst->m_CompletionNewData, 0);
 800         return 0;
 801 }
 802
 803 //---------------------------------------------------------------------------
 804 //  Thread for new data Job Ready signaling
 805 //---------------------------------------------------------------------------
 806
 807 int ShbIpcThreadSignalJobReady(void *pvThreadParam_p)
 808 {
 809         tShbInstance pShbInstance;
 810         tShbMemInst *pShbMemInst;
 811         tShbMemHeader *pShbMemHeader;
 812         long lTimeOut;
 813         int iRetVal = -1;
 814
 815         daemonize("ShbJR%p", pvThreadParam_p);
 816         allow_signal(SIGTERM);
 817         pShbInstance = (tShbMemInst *) pvThreadParam_p;
 818         pShbMemInst = ShbIpcGetShbMemInst(pShbInstance);
 819         pShbMemHeader = ShbIpcGetShbMemHeader(pShbMemInst);
 820
 821         DEBUG_LVL_29_TRACE0
 822             ("ShbIpcThreadSignalJobReady wait for job ready Sem\n");
 823         if (pShbMemInst->m_ulTimeOutJobReady != 0) {
 824                 lTimeOut = (long)pShbMemInst->m_ulTimeOutJobReady;
 825                 //wait for job ready semaphore
 826                 iRetVal =
 827                     wait_event_interruptible_timeout(pShbMemHeader->
 828                                                      m_WaitQueueJobReady,
 829                                                      (pShbMemHeader->
 830                                                       m_fJobReady != FALSE),
 831                                                      lTimeOut);
 832         } else {
 833                 //wait for job ready semaphore
 834                 iRetVal =
 835                     wait_event_interruptible(pShbMemHeader->m_WaitQueueJobReady,
 836                                              (pShbMemHeader->m_fJobReady !=
 837                                               FALSE));
 838         }
 839
 840         if (pShbMemInst->m_pfnSigHndlrJobReady != NULL) {
 841                 //call Handler
 842                 pShbMemInst->m_pfnSigHndlrJobReady(pShbInstance,
 843                                                    !pShbMemHeader->m_fJobReady);
 844         }
 845
 846         pShbMemInst->m_pfnSigHndlrJobReady = NULL;
 847         return 0;
 848 }
 849
 850 //Build the crc table
 851 static void ShbIpcCrc32GenTable(unsigned long aulCrcTable[256])
 852 {
 853         unsigned long ulCrc, ulPoly;
 854         int iIndexI, iIndexJ;
 855
 856         ulPoly = 0xEDB88320L;
 857         for (iIndexI = 0; iIndexI < 256; iIndexI++) {
 858                 ulCrc = iIndexI;
 859                 for (iIndexJ = 8; iIndexJ > 0; iIndexJ--) {
 860                         if (ulCrc & 1) {
 861                                 ulCrc = (ulCrc >> 1) ^ ulPoly;
 862                         } else {
 863                                 ulCrc >>= 1;
 864                         }
 865                 }
 866                 aulCrcTable[iIndexI] = ulCrc;
 867         }
 868 }
 869
 870 //Calculate the crc value
 871 static unsigned long ShbIpcCrc32GetCrc(const char *pcString,
 872                                        unsigned long aulCrcTable[256])
 873 {
 874         unsigned long ulCrc;
 875         int iIndex;
 876
 877         ulCrc = 0xFFFFFFFF;
 878         for (iIndex = 0; iIndex < strlen(pcString); iIndex++) {
 879                 ulCrc =
 880                     ((ulCrc >> 8) & 0x00FFFFFF) ^
 881                     aulCrcTable[(ulCrc ^ pcString[iIndex]) & 0xFF];
 882         }
 883         return (ulCrc ^ 0xFFFFFFFF);
 884
 885 }
 886
 887 static void ShbIpcAppendListElement(struct sShbMemTable *psNewMemTableElement)
 888 {
 889         struct sShbMemTable *psMemTableElement = psMemTableElementFirst_g;
 890         psNewMemTableElement->m_psNextMemTableElement = NULL;
 891
 892         if (psMemTableElementFirst_g != NULL) { /* sind Elemente vorhanden */
 893                 while (psMemTableElement->m_psNextMemTableElement != NULL) {    /* suche das letzte Element */
 894                         psMemTableElement =
 895                             psMemTableElement->m_psNextMemTableElement;
 896                 }
 897                 psMemTableElement->m_psNextMemTableElement = psNewMemTableElement;      /*  Haenge das Element hinten an */
 898         } else {                /* wenn die liste leer ist, bin ich das erste Element */
 899                 psMemTableElementFirst_g = psNewMemTableElement;
 900         }
 901 }
 902
 903 static int ShbIpcFindListElement(int iBufferId,
 904                                  struct sShbMemTable **ppsReturnMemTableElement)
 905 {
 906         struct sShbMemTable *psMemTableElement = psMemTableElementFirst_g;
 907         while (psMemTableElement != NULL) {
 908                 if (psMemTableElement->m_iBufferId == iBufferId) {
 909 //printk("ShbIpcFindListElement Buffer at:%p Id:%d\n",psMemTableElement->m_pBuffer,psMemTableElement->m_iBufferId);
 910                         *ppsReturnMemTableElement = psMemTableElement;
 911 //printk("ShbIpcFindListElement Buffer at:%p Id:%d\n",(*ppsReturnMemTableElement)->m_pBuffer,(*ppsReturnMemTableElement)->m_iBufferId);
 912                         return 0;
 913                 }
 914                 psMemTableElement = psMemTableElement->m_psNextMemTableElement;
 915         }
 916         return -1;
 917 }
 918
 919 static void ShbIpcDeleteListElement(int iBufferId)
 920 {
 921         struct sShbMemTable *psMemTableElement = psMemTableElementFirst_g;
 922         struct sShbMemTable *psMemTableElementOld = psMemTableElementFirst_g;
 923         if (psMemTableElement != NULL) {
 924                 while ((psMemTableElement != NULL)
 925                        && (psMemTableElement->m_iBufferId != iBufferId)) {
 926                         psMemTableElementOld = psMemTableElement;
 927                         psMemTableElement =
 928                             psMemTableElement->m_psNextMemTableElement;
 929                 }
 930                 if (psMemTableElement != NULL) {
 931                         if (psMemTableElement != psMemTableElementFirst_g) {
 932                                 psMemTableElementOld->m_psNextMemTableElement =
 933                                     psMemTableElement->m_psNextMemTableElement;
 934                                 kfree(psMemTableElement);
 935                         } else {
 936                                 kfree(psMemTableElement);
 937                                 psMemTableElementFirst_g = NULL;
 938                         }
 939
 940                 }
 941         }
 942
 943 }
 944