Date: 2021-03-03T22:26:53+00:00

Actual source code: dmshell.c
petsc-3.14.5 2021-03-03
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      1: #include <petscdmshell.h>
      2: #include <petscmat.h>
      3: #include <petsc/private/dmimpl.h>

      5: typedef struct  {
      6:   Vec        Xglobal;
      7:   Vec        Xlocal;
      8:   Mat        A;
      9:   VecScatter gtol;
     10:   VecScatter ltog;
     11:   VecScatter ltol;
     12:   void       *ctx;
     13: } DM_Shell;

     15: /*@
     16:    DMGlobalToLocalBeginDefaultShell - Uses the GlobalToLocal VecScatter context set by the user to begin a global to local scatter
     17:    Collective

     19:    Input Arguments:
     20: +  dm - shell DM
     21: .  g - global vector
     22: .  mode - InsertMode
     23: -  l - local vector

     25:    Level: advanced

     27:    Note:  This is not normally called directly by user code, generally user code calls DMGlobalToLocalBegin() and DMGlobalToLocalEnd(). If the user provides their own custom routines to DMShellSetLocalToGlobal() then those routines might have reason to call this function.

     29: .seealso: DMGlobalToLocalEndDefaultShell()
     30: @*/
     31: PetscErrorCode DMGlobalToLocalBeginDefaultShell(DM dm,Vec g,InsertMode mode,Vec l)
     32: {
     34:   DM_Shell       *shell = (DM_Shell*)dm->data;

     37:   if (!shell->gtol) SETERRQ(((PetscObject)dm)->comm,PETSC_ERR_ARG_WRONGSTATE, "Cannot be used without first setting the scatter context via DMShellSetGlobalToLocalVecScatter()");
     38:   VecScatterBegin(shell->gtol,g,l,mode,SCATTER_FORWARD);
     39:   return(0);
     40: }

     42: /*@
     43:    DMGlobalToLocalEndDefaultShell - Uses the GlobalToLocal VecScatter context set by the user to end a global to local scatter
     44:    Collective

     46:    Input Arguments:
     47: +  dm - shell DM
     48: .  g - global vector
     49: .  mode - InsertMode
     50: -  l - local vector

     52:    Level: advanced

     54: .seealso: DMGlobalToLocalBeginDefaultShell()
     55: @*/
     56: PetscErrorCode DMGlobalToLocalEndDefaultShell(DM dm,Vec g,InsertMode mode,Vec l)
     57: {
     59:   DM_Shell       *shell = (DM_Shell*)dm->data;

     62:    if (!shell->gtol) SETERRQ(((PetscObject)dm)->comm,PETSC_ERR_ARG_WRONGSTATE, "Cannot be used without first setting the scatter context via DMShellSetGlobalToLocalVecScatter()");
     63:   VecScatterEnd(shell->gtol,g,l,mode,SCATTER_FORWARD);
     64:   return(0);
     65: }

     67: /*@
     68:    DMLocalToGlobalBeginDefaultShell - Uses the LocalToGlobal VecScatter context set by the user to begin a local to global scatter
     69:    Collective

     71:    Input Arguments:
     72: +  dm - shell DM
     73: .  l - local vector
     74: .  mode - InsertMode
     75: -  g - global vector

     77:    Level: advanced

     79:    Note:  This is not normally called directly by user code, generally user code calls DMLocalToGlobalBegin() and DMLocalToGlobalEnd(). If the user provides their own custom routines to DMShellSetLocalToGlobal() then those routines might have reason to call this function.

     81: .seealso: DMLocalToGlobalEndDefaultShell()
     82: @*/
     83: PetscErrorCode DMLocalToGlobalBeginDefaultShell(DM dm,Vec l,InsertMode mode,Vec g)
     84: {
     86:   DM_Shell       *shell = (DM_Shell*)dm->data;

     89:   if (!shell->ltog) SETERRQ(((PetscObject)dm)->comm,PETSC_ERR_ARG_WRONGSTATE, "Cannot be used without first setting the scatter context via DMShellSetLocalToGlobalVecScatter()");
     90:   VecScatterBegin(shell->ltog,l,g,mode,SCATTER_FORWARD);
     91:   return(0);
     92: }

     94: /*@
     95:    DMLocalToGlobalEndDefaultShell - Uses the LocalToGlobal VecScatter context set by the user to end a local to global scatter
     96:    Collective

     98:    Input Arguments:
     99: +  dm - shell DM
    100: .  l - local vector
    101: .  mode - InsertMode
    102: -  g - global vector

    104:    Level: advanced

    106: .seealso: DMLocalToGlobalBeginDefaultShell()
    107: @*/
    108: PetscErrorCode DMLocalToGlobalEndDefaultShell(DM dm,Vec l,InsertMode mode,Vec g)
    109: {
    111:   DM_Shell       *shell = (DM_Shell*)dm->data;

    114:    if (!shell->ltog) SETERRQ(((PetscObject)dm)->comm,PETSC_ERR_ARG_WRONGSTATE, "Cannot be used without first setting the scatter context via DMShellSetLocalToGlobalVecScatter()");
    115:   VecScatterEnd(shell->ltog,l,g,mode,SCATTER_FORWARD);
    116:   return(0);
    117: }

    119: /*@
    120:    DMLocalToLocalBeginDefaultShell - Uses the LocalToLocal VecScatter context set by the user to begin a local to local scatter
    121:    Collective

    123:    Input Arguments:
    124: +  dm - shell DM
    125: .  g - the original local vector
    126: -  mode - InsertMode

    128:    Output Parameter:
    129: .  l  - the local vector with correct ghost values

    131:    Level: advanced

    133:    Note:  This is not normally called directly by user code, generally user code calls DMLocalToLocalBegin() and DMLocalToLocalEnd(). If the user provides their own custom routines to DMShellSetLocalToLocal() then those routines might have reason to call this function.

    135: .seealso: DMLocalToLocalEndDefaultShell()
    136: @*/
    137: PetscErrorCode DMLocalToLocalBeginDefaultShell(DM dm,Vec g,InsertMode mode,Vec l)
    138: {
    140:   DM_Shell       *shell = (DM_Shell*)dm->data;

    143:   if (!shell->ltol) SETERRQ(((PetscObject)dm)->comm,PETSC_ERR_ARG_WRONGSTATE, "Cannot be used without first setting the scatter context via DMShellSetLocalToLocalVecScatter()");
    144:   VecScatterBegin(shell->ltol,g,l,mode,SCATTER_FORWARD);
    145:   return(0);
    146: }

    148: /*@
    149:    DMLocalToLocalEndDefaultShell - Uses the LocalToLocal VecScatter context set by the user to end a local to local scatter
    150:    Collective

    152:    Input Arguments:
    153: +  dm - shell DM
    154: .  g - the original local vector
    155: -  mode - InsertMode

    157:    Output Parameter:
    158: .  l  - the local vector with correct ghost values

    160:    Level: advanced

    162: .seealso: DMLocalToLocalBeginDefaultShell()
    163: @*/
    164: PetscErrorCode DMLocalToLocalEndDefaultShell(DM dm,Vec g,InsertMode mode,Vec l)
    165: {
    167:   DM_Shell       *shell = (DM_Shell*)dm->data;

    170:    if (!shell->ltol) SETERRQ(((PetscObject)dm)->comm,PETSC_ERR_ARG_WRONGSTATE, "Cannot be used without first setting the scatter context via DMShellSetGlobalToLocalVecScatter()");
    171:   VecScatterEnd(shell->ltol,g,l,mode,SCATTER_FORWARD);
    172:   return(0);
    173: }

    175: static PetscErrorCode DMCreateMatrix_Shell(DM dm,Mat *J)
    176: {
    178:   DM_Shell       *shell = (DM_Shell*)dm->data;
    179:   Mat            A;

    184:   if (!shell->A) {
    185:     if (shell->Xglobal) {
    186:       PetscInt m,M;
    187:       PetscInfo(dm,"Naively creating matrix using global vector distribution without preallocation\n");
    188:       VecGetSize(shell->Xglobal,&M);
    189:       VecGetLocalSize(shell->Xglobal,&m);
    190:       MatCreate(PetscObjectComm((PetscObject)dm),&shell->A);
    191:       MatSetSizes(shell->A,m,m,M,M);
    192:       MatSetType(shell->A,dm->mattype);
    193:       MatSetUp(shell->A);
    194:     } else SETERRQ(PetscObjectComm((PetscObject)dm),PETSC_ERR_USER,"Must call DMShellSetMatrix(), DMShellSetCreateMatrix(), or provide a vector");
    195:   }
    196:   A = shell->A;
    197:   MatDuplicate(A,MAT_SHARE_NONZERO_PATTERN,J);
    198:   MatSetDM(*J,dm);
    199:   return(0);
    200: }

    202: PetscErrorCode DMCreateGlobalVector_Shell(DM dm,Vec *gvec)
    203: {
    205:   DM_Shell       *shell = (DM_Shell*)dm->data;
    206:   Vec            X;

    211:   *gvec = NULL;
    212:   X     = shell->Xglobal;
    213:   if (!X) SETERRQ(PetscObjectComm((PetscObject)dm),PETSC_ERR_USER,"Must call DMShellSetGlobalVector() or DMShellSetCreateGlobalVector()");
    214:   /* Need to create a copy in order to attach the DM to the vector */
    215:   VecDuplicate(X,gvec);
    216:   VecZeroEntries(*gvec);
    217:   VecSetDM(*gvec,dm);
    218:   return(0);
    219: }

    221: PetscErrorCode DMCreateLocalVector_Shell(DM dm,Vec *gvec)
    222: {
    224:   DM_Shell       *shell = (DM_Shell*)dm->data;
    225:   Vec            X;

    230:   *gvec = NULL;
    231:   X     = shell->Xlocal;
    232:   if (!X) SETERRQ(PetscObjectComm((PetscObject)dm),PETSC_ERR_USER,"Must call DMShellSetLocalVector() or DMShellSetCreateLocalVector()");
    233:   /* Need to create a copy in order to attach the DM to the vector */
    234:   VecDuplicate(X,gvec);
    235:   VecZeroEntries(*gvec);
    236:   VecSetDM(*gvec,dm);
    237:   return(0);
    238: }

    240: /*@
    241:    DMShellSetContext - set some data to be usable by this DM

    243:    Collective

    245:    Input Arguments:
    246: +  dm - shell DM
    247: -  ctx - the context

    249:    Level: advanced

    251: .seealso: DMCreateMatrix(), DMShellGetContext()
    252: @*/
    253: PetscErrorCode DMShellSetContext(DM dm,void *ctx)
    254: {
    255:   DM_Shell       *shell = (DM_Shell*)dm->data;
    257:   PetscBool      isshell;

    261:   PetscObjectTypeCompare((PetscObject)dm,DMSHELL,&isshell);
    262:   if (!isshell) return(0);
    263:   shell->ctx = ctx;
    264:   return(0);
    265: }

    267: /*@
    268:    DMShellGetContext - Returns the user-provided context associated to the DM

    270:    Collective

    272:    Input Argument:
    273: .  dm - shell DM

    275:    Output Argument:
    276: .  ctx - the context

    278:    Level: advanced

    280: .seealso: DMCreateMatrix(), DMShellSetContext()
    281: @*/
    282: PetscErrorCode DMShellGetContext(DM dm,void **ctx)
    283: {
    284:   DM_Shell       *shell = (DM_Shell*)dm->data;
    286:   PetscBool      isshell;

    290:   PetscObjectTypeCompare((PetscObject)dm,DMSHELL,&isshell);
    291:   if (!isshell) SETERRQ(PetscObjectComm((PetscObject)dm),PETSC_ERR_SUP,"Can only use with DMSHELL type DMs");
    292:   *ctx = shell->ctx;
    293:   return(0);
    294: }

    296: /*@
    297:    DMShellSetMatrix - sets a template matrix associated with the DMShell

    299:    Collective

    301:    Input Arguments:
    302: +  dm - shell DM
    303: -  J - template matrix

    305:    Level: advanced

    307:    Developer Notes:
    308:     To avoid circular references, if J is already associated to the same DM, then MatDuplicate(SHARE_NONZERO_PATTERN) is called, followed by removing the DM reference from the private template.

    310: .seealso: DMCreateMatrix(), DMShellSetCreateMatrix(), DMShellSetContext(), DMShellGetContext()
    311: @*/
    312: PetscErrorCode DMShellSetMatrix(DM dm,Mat J)
    313: {
    314:   DM_Shell       *shell = (DM_Shell*)dm->data;
    316:   PetscBool      isshell;
    317:   DM             mdm;

    322:   PetscObjectTypeCompare((PetscObject)dm,DMSHELL,&isshell);
    323:   if (!isshell) return(0);
    324:   if (J == shell->A) return(0);
    325:   MatGetDM(J,&mdm);
    326:   PetscObjectReference((PetscObject)J);
    327:   MatDestroy(&shell->A);
    328:   if (mdm == dm) {
    329:     MatDuplicate(J,MAT_SHARE_NONZERO_PATTERN,&shell->A);
    330:     MatSetDM(shell->A,NULL);
    331:   } else shell->A = J;
    332:   return(0);
    333: }

    335: /*@C
    336:    DMShellSetCreateMatrix - sets the routine to create a matrix associated with the shell DM

    338:    Logically Collective on dm

    340:    Input Arguments:
    341: +  dm - the shell DM
    342: -  func - the function to create a matrix

    344:    Level: advanced

    346: .seealso: DMCreateMatrix(), DMShellSetMatrix(), DMShellSetContext(), DMShellGetContext()
    347: @*/
    348: PetscErrorCode DMShellSetCreateMatrix(DM dm,PetscErrorCode (*func)(DM,Mat*))
    349: {
    352:   dm->ops->creatematrix = func;
    353:   return(0);
    354: }

    356: /*@
    357:    DMShellSetGlobalVector - sets a template global vector associated with the DMShell

    359:    Logically Collective on dm

    361:    Input Arguments:
    362: +  dm - shell DM
    363: -  X - template vector

    365:    Level: advanced

    367: .seealso: DMCreateGlobalVector(), DMShellSetMatrix(), DMShellSetCreateGlobalVector()
    368: @*/
    369: PetscErrorCode DMShellSetGlobalVector(DM dm,Vec X)
    370: {
    371:   DM_Shell       *shell = (DM_Shell*)dm->data;
    373:   PetscBool      isshell;
    374:   DM             vdm;

    379:   PetscObjectTypeCompare((PetscObject)dm,DMSHELL,&isshell);
    380:   if (!isshell) return(0);
    381:   VecGetDM(X,&vdm);
    382:   /*
    383:       if the vector proposed as the new base global vector for the DM is a DM vector associated
    384:       with the same DM then the current base global vector for the DM is ok and if we replace it with the new one
    385:       we get a circular dependency that prevents the DM from being destroy when it should be.
    386:       This occurs when SNESSet/GetNPC() is used with a SNES that does not have a user provided
    387:       DM attached to it since the inner SNES (which shares the DM with the outer SNES) tries
    388:       to set its input vector (which is associated with the DM) as the base global vector.
    389:       Thanks to Juan P. Mendez Granado Re: [petsc-maint] Nonlinear conjugate gradien
    390:       for pointing out the problem.
    391:    */
    392:   if (vdm == dm) return(0);
    393:   PetscObjectReference((PetscObject)X);
    394:   VecDestroy(&shell->Xglobal);
    395:   shell->Xglobal = X;
    396:   return(0);
    397: }

    399: /*@C
    400:    DMShellSetCreateGlobalVector - sets the routine to create a global vector associated with the shell DM

    402:    Logically Collective

    404:    Input Arguments:
    405: +  dm - the shell DM
    406: -  func - the creation routine

    408:    Level: advanced

    410: .seealso: DMShellSetGlobalVector(), DMShellSetCreateMatrix(), DMShellSetContext(), DMShellGetContext()
    411: @*/
    412: PetscErrorCode DMShellSetCreateGlobalVector(DM dm,PetscErrorCode (*func)(DM,Vec*))
    413: {
    416:   dm->ops->createglobalvector = func;
    417:   return(0);
    418: }

    420: /*@
    421:    DMShellSetLocalVector - sets a template local vector associated with the DMShell

    423:    Logically Collective on dm

    425:    Input Arguments:
    426: +  dm - shell DM
    427: -  X - template vector

    429:    Level: advanced

    431: .seealso: DMCreateLocalVector(), DMShellSetMatrix(), DMShellSetCreateLocalVector()
    432: @*/
    433: PetscErrorCode DMShellSetLocalVector(DM dm,Vec X)
    434: {
    435:   DM_Shell       *shell = (DM_Shell*)dm->data;
    437:   PetscBool      isshell;
    438:   DM             vdm;

    443:   PetscObjectTypeCompare((PetscObject)dm,DMSHELL,&isshell);
    444:   if (!isshell) return(0);
    445:   VecGetDM(X,&vdm);
    446:   /*
    447:       if the vector proposed as the new base global vector for the DM is a DM vector associated
    448:       with the same DM then the current base global vector for the DM is ok and if we replace it with the new one
    449:       we get a circular dependency that prevents the DM from being destroy when it should be.
    450:       This occurs when SNESSet/GetNPC() is used with a SNES that does not have a user provided
    451:       DM attached to it since the inner SNES (which shares the DM with the outer SNES) tries
    452:       to set its input vector (which is associated with the DM) as the base global vector.
    453:       Thanks to Juan P. Mendez Granado Re: [petsc-maint] Nonlinear conjugate gradien
    454:       for pointing out the problem.
    455:    */
    456:   if (vdm == dm) return(0);
    457:   PetscObjectReference((PetscObject)X);
    458:   VecDestroy(&shell->Xlocal);
    459:   shell->Xlocal = X;
    460:   return(0);
    461: }

    463: /*@C
    464:    DMShellSetCreateLocalVector - sets the routine to create a local vector associated with the shell DM

    466:    Logically Collective

    468:    Input Arguments:
    469: +  dm - the shell DM
    470: -  func - the creation routine

    472:    Level: advanced

    474: .seealso: DMShellSetLocalVector(), DMShellSetCreateMatrix(), DMShellSetContext(), DMShellGetContext()
    475: @*/
    476: PetscErrorCode DMShellSetCreateLocalVector(DM dm,PetscErrorCode (*func)(DM,Vec*))
    477: {
    480:   dm->ops->createlocalvector = func;
    481:   return(0);
    482: }

    484: /*@C
    485:    DMShellSetGlobalToLocal - Sets the routines used to perform a global to local scatter

    487:    Logically Collective on dm

    489:    Input Arguments
    490: +  dm - the shell DM
    491: .  begin - the routine that begins the global to local scatter
    492: -  end - the routine that ends the global to local scatter

    494:    Notes:
    495:     If these functions are not provided but DMShellSetGlobalToLocalVecScatter() is called then
    496:    DMGlobalToLocalBeginDefaultShell()/DMGlobalToLocalEndDefaultShell() are used to to perform the transfers

    498:    Level: advanced

    500: .seealso: DMShellSetLocalToGlobal(), DMGlobalToLocalBeginDefaultShell(), DMGlobalToLocalEndDefaultShell()
    501: @*/
    502: PetscErrorCode DMShellSetGlobalToLocal(DM dm,PetscErrorCode (*begin)(DM,Vec,InsertMode,Vec),PetscErrorCode (*end)(DM,Vec,InsertMode,Vec)) {
    505:   dm->ops->globaltolocalbegin = begin;
    506:   dm->ops->globaltolocalend = end;
    507:   return(0);
    508: }

    510: /*@C
    511:    DMShellSetLocalToGlobal - Sets the routines used to perform a local to global scatter

    513:    Logically Collective on dm

    515:    Input Arguments
    516: +  dm - the shell DM
    517: .  begin - the routine that begins the local to global scatter
    518: -  end - the routine that ends the local to global scatter

    520:    Notes:
    521:     If these functions are not provided but DMShellSetLocalToGlobalVecScatter() is called then
    522:    DMLocalToGlobalBeginDefaultShell()/DMLocalToGlobalEndDefaultShell() are used to to perform the transfers

    524:    Level: advanced

    526: .seealso: DMShellSetGlobalToLocal()
    527: @*/
    528: PetscErrorCode DMShellSetLocalToGlobal(DM dm,PetscErrorCode (*begin)(DM,Vec,InsertMode,Vec),PetscErrorCode (*end)(DM,Vec,InsertMode,Vec)) {
    531:   dm->ops->localtoglobalbegin = begin;
    532:   dm->ops->localtoglobalend = end;
    533:   return(0);
    534: }

    536: /*@C
    537:    DMShellSetLocalToLocal - Sets the routines used to perform a local to local scatter

    539:    Logically Collective on dm

    541:    Input Arguments
    542: +  dm - the shell DM
    543: .  begin - the routine that begins the local to local scatter
    544: -  end - the routine that ends the local to local scatter

    546:    Notes:
    547:     If these functions are not provided but DMShellSetLocalToLocalVecScatter() is called then
    548:    DMLocalToLocalBeginDefaultShell()/DMLocalToLocalEndDefaultShell() are used to to perform the transfers

    550:    Level: advanced

    552: .seealso: DMShellSetGlobalToLocal(), DMLocalToLocalBeginDefaultShell(), DMLocalToLocalEndDefaultShell()
    553: @*/
    554: PetscErrorCode DMShellSetLocalToLocal(DM dm,PetscErrorCode (*begin)(DM,Vec,InsertMode,Vec),PetscErrorCode (*end)(DM,Vec,InsertMode,Vec)) {
    557:   dm->ops->localtolocalbegin = begin;
    558:   dm->ops->localtolocalend = end;
    559:   return(0);
    560: }

    562: /*@
    563:    DMShellSetGlobalToLocalVecScatter - Sets a VecScatter context for global to local communication

    565:    Logically Collective on dm

    567:    Input Arguments
    568: +  dm - the shell DM
    569: -  gtol - the global to local VecScatter context

    571:    Level: advanced

    573: .seealso: DMShellSetGlobalToLocal(), DMGlobalToLocalBeginDefaultShell(), DMGlobalToLocalEndDefaultShell()
    574: @*/
    575: PetscErrorCode DMShellSetGlobalToLocalVecScatter(DM dm, VecScatter gtol)
    576: {
    577:   DM_Shell       *shell = (DM_Shell*)dm->data;

    583:   PetscObjectReference((PetscObject)gtol);
    584:   VecScatterDestroy(&shell->gtol);
    585:   shell->gtol = gtol;
    586:   return(0);
    587: }

    589: /*@
    590:    DMShellSetLocalToGlobalVecScatter - Sets a VecScatter context for local to global communication

    592:    Logically Collective on dm

    594:    Input Arguments
    595: +  dm - the shell DM
    596: -  ltog - the local to global VecScatter context

    598:    Level: advanced

    600: .seealso: DMShellSetLocalToGlobal(), DMLocalToGlobalBeginDefaultShell(), DMLocalToGlobalEndDefaultShell()
    601: @*/
    602: PetscErrorCode DMShellSetLocalToGlobalVecScatter(DM dm, VecScatter ltog)
    603: {
    604:   DM_Shell       *shell = (DM_Shell*)dm->data;

    610:   PetscObjectReference((PetscObject)ltog);
    611:   VecScatterDestroy(&shell->ltog);
    612:   shell->ltog = ltog;
    613:   return(0);
    614: }

    616: /*@
    617:    DMShellSetLocalToLocalVecScatter - Sets a VecScatter context for local to local communication

    619:    Logically Collective on dm

    621:    Input Arguments
    622: +  dm - the shell DM
    623: -  ltol - the local to local VecScatter context

    625:    Level: advanced

    627: .seealso: DMShellSetLocalToLocal(), DMLocalToLocalBeginDefaultShell(), DMLocalToLocalEndDefaultShell()
    628: @*/
    629: PetscErrorCode DMShellSetLocalToLocalVecScatter(DM dm, VecScatter ltol)
    630: {
    631:   DM_Shell       *shell = (DM_Shell*)dm->data;

    637:   PetscObjectReference((PetscObject)ltol);
    638:   VecScatterDestroy(&shell->ltol);
    639:   shell->ltol = ltol;
    640:   return(0);
    641: }

    643: /*@C
    644:    DMShellSetCoarsen - Set the routine used to coarsen the shell DM

    646:    Logically Collective on dm

    648:    Input Arguments
    649: +  dm - the shell DM
    650: -  coarsen - the routine that coarsens the DM

    652:    Level: advanced

    654: .seealso: DMShellSetRefine(), DMCoarsen(), DMShellGetCoarsen(), DMShellSetContext(), DMShellGetContext()
    655: @*/
    656: PetscErrorCode DMShellSetCoarsen(DM dm, PetscErrorCode (*coarsen)(DM,MPI_Comm,DM*))
    657: {
    659:   PetscBool      isshell;

    663:   PetscObjectTypeCompare((PetscObject)dm,DMSHELL,&isshell);
    664:   if (!isshell) return(0);
    665:   dm->ops->coarsen = coarsen;
    666:   return(0);
    667: }

    669: /*@C
    670:    DMShellGetCoarsen - Get the routine used to coarsen the shell DM

    672:    Logically Collective on dm

    674:    Input Argument:
    675: .  dm - the shell DM

    677:    Output Argument:
    678: .  coarsen - the routine that coarsens the DM

    680:    Level: advanced

    682: .seealso: DMShellSetCoarsen(), DMCoarsen(), DMShellSetRefine(), DMRefine()
    683: @*/
    684: PetscErrorCode DMShellGetCoarsen(DM dm, PetscErrorCode (**coarsen)(DM,MPI_Comm,DM*))
    685: {
    687:   PetscBool      isshell;

    691:   PetscObjectTypeCompare((PetscObject)dm,DMSHELL,&isshell);
    692:   if (!isshell) SETERRQ(PetscObjectComm((PetscObject)dm),PETSC_ERR_SUP,"Can only use with DMSHELL type DMs");
    693:   *coarsen = dm->ops->coarsen;
    694:   return(0);
    695: }

    697: /*@C
    698:    DMShellSetRefine - Set the routine used to refine the shell DM

    700:    Logically Collective on dm

    702:    Input Arguments
    703: +  dm - the shell DM
    704: -  refine - the routine that refines the DM

    706:    Level: advanced

    708: .seealso: DMShellSetCoarsen(), DMRefine(), DMShellGetRefine(), DMShellSetContext(), DMShellGetContext()
    709: @*/
    710: PetscErrorCode DMShellSetRefine(DM dm, PetscErrorCode (*refine)(DM,MPI_Comm,DM*))
    711: {
    713:   PetscBool      isshell;

    717:   PetscObjectTypeCompare((PetscObject)dm,DMSHELL,&isshell);
    718:   if (!isshell) return(0);
    719:   dm->ops->refine = refine;
    720:   return(0);
    721: }

    723: /*@C
    724:    DMShellGetRefine - Get the routine used to refine the shell DM

    726:    Logically Collective on dm

    728:    Input Argument:
    729: .  dm - the shell DM

    731:    Output Argument:
    732: .  refine - the routine that refines the DM

    734:    Level: advanced

    736: .seealso: DMShellSetCoarsen(), DMCoarsen(), DMShellSetRefine(), DMRefine()
    737: @*/
    738: PetscErrorCode DMShellGetRefine(DM dm, PetscErrorCode (**refine)(DM,MPI_Comm,DM*))
    739: {
    741:   PetscBool      isshell;

    745:   PetscObjectTypeCompare((PetscObject)dm,DMSHELL,&isshell);
    746:   if (!isshell) SETERRQ(PetscObjectComm((PetscObject)dm),PETSC_ERR_SUP,"Can only use with DMSHELL type DMs");
    747:   *refine = dm->ops->refine;
    748:   return(0);
    749: }

    751: /*@C
    752:    DMShellSetCreateInterpolation - Set the routine used to create the interpolation operator

    754:    Logically Collective on dm

    756:    Input Arguments
    757: +  dm - the shell DM
    758: -  interp - the routine to create the interpolation

    760:    Level: advanced

    762: .seealso: DMShellSetCreateInjection(), DMCreateInterpolation(), DMShellGetCreateInterpolation(), DMShellSetCreateRestriction(), DMShellSetContext(), DMShellGetContext()
    763: @*/
    764: PetscErrorCode DMShellSetCreateInterpolation(DM dm, PetscErrorCode (*interp)(DM,DM,Mat*,Vec*))
    765: {
    767:   PetscBool      isshell;

    771:   PetscObjectTypeCompare((PetscObject)dm,DMSHELL,&isshell);
    772:   if (!isshell) return(0);
    773:   dm->ops->createinterpolation = interp;
    774:   return(0);
    775: }

    777: /*@C
    778:    DMShellGetCreateInterpolation - Get the routine used to create the interpolation operator

    780:    Logically Collective on dm

    782:    Input Argument:
    783: +  dm - the shell DM

    785:    Output Argument:
    786: -  interp - the routine to create the interpolation

    788:    Level: advanced

    790: .seealso: DMShellGetCreateInjection(), DMCreateInterpolation(), DMShellGetCreateRestriction(), DMShellSetContext(), DMShellGetContext()
    791: @*/
    792: PetscErrorCode DMShellGetCreateInterpolation(DM dm, PetscErrorCode (**interp)(DM,DM,Mat*,Vec*))
    793: {
    795:   PetscBool      isshell;

    799:   PetscObjectTypeCompare((PetscObject)dm,DMSHELL,&isshell);
    800:   if (!isshell) SETERRQ(PetscObjectComm((PetscObject)dm),PETSC_ERR_SUP,"Can only use with DMSHELL type DMs");
    801:   *interp = dm->ops->createinterpolation;
    802:   return(0);
    803: }

    805: /*@C
    806:    DMShellSetCreateRestriction - Set the routine used to create the restriction operator

    808:    Logically Collective on dm

    810:    Input Arguments
    811: +  dm - the shell DM
    812: -  striction- the routine to create the restriction

    814:    Level: advanced

    816: .seealso: DMShellSetCreateInjection(), DMCreateInterpolation(), DMShellGetCreateRestriction(), DMShellSetContext(), DMShellGetContext()
    817: @*/
    818: PetscErrorCode DMShellSetCreateRestriction(DM dm, PetscErrorCode (*restriction)(DM,DM,Mat*))
    819: {
    821:   PetscBool      isshell;

    825:   PetscObjectTypeCompare((PetscObject)dm,DMSHELL,&isshell);
    826:   if (!isshell) return(0);
    827:   dm->ops->createrestriction = restriction;
    828:   return(0);
    829: }

    831: /*@C
    832:    DMShellGetCreateRestriction - Get the routine used to create the restriction operator

    834:    Logically Collective on dm

    836:    Input Argument:
    837: +  dm - the shell DM

    839:    Output Argument:
    840: -  restriction - the routine to create the restriction

    842:    Level: advanced

    844: .seealso: DMShellSetCreateInjection(), DMCreateInterpolation(), DMShellSetContext(), DMShellGetContext()
    845: @*/
    846: PetscErrorCode DMShellGetCreateRestriction(DM dm, PetscErrorCode (**restriction)(DM,DM,Mat*))
    847: {
    849:   PetscBool      isshell;

    853:   PetscObjectTypeCompare((PetscObject)dm,DMSHELL,&isshell);
    854:   if (!isshell) SETERRQ(PetscObjectComm((PetscObject)dm),PETSC_ERR_SUP,"Can only use with DMSHELL type DMs");
    855:   *restriction = dm->ops->createrestriction;
    856:   return(0);
    857: }

    859: /*@C
    860:    DMShellSetCreateInjection - Set the routine used to create the injection operator

    862:    Logically Collective on dm

    864:    Input Arguments
    865: +  dm - the shell DM
    866: -  inject - the routine to create the injection

    868:    Level: advanced

    870: .seealso: DMShellSetCreateInterpolation(), DMCreateInjection(), DMShellGetCreateInjection(), DMShellSetContext(), DMShellGetContext()
    871: @*/
    872: PetscErrorCode DMShellSetCreateInjection(DM dm, PetscErrorCode (*inject)(DM,DM,Mat*))
    873: {
    875:   PetscBool      isshell;

    879:   PetscObjectTypeCompare((PetscObject)dm,DMSHELL,&isshell);
    880:   if (!isshell) return(0);
    881:   dm->ops->createinjection = inject;
    882:   return(0);
    883: }

    885: /*@C
    886:    DMShellGetCreateInjection - Get the routine used to create the injection operator

    888:    Logically Collective on dm

    890:    Input Argument:
    891: +  dm - the shell DM

    893:    Output Argument:
    894: -  inject - the routine to create the injection

    896:    Level: advanced

    898: .seealso: DMShellGetCreateInterpolation(), DMCreateInjection(), DMShellSetContext(), DMShellGetContext()
    899: @*/
    900: PetscErrorCode DMShellGetCreateInjection(DM dm, PetscErrorCode (**inject)(DM,DM,Mat*))
    901: {
    903:   PetscBool      isshell;

    907:   PetscObjectTypeCompare((PetscObject)dm,DMSHELL,&isshell);
    908:   if (!isshell) SETERRQ(PetscObjectComm((PetscObject)dm),PETSC_ERR_SUP,"Can only use with DMSHELL type DMs");
    909:   *inject = dm->ops->createinjection;
    910:   return(0);
    911: }

    913: /*@C
    914:    DMShellSetCreateFieldDecomposition - Set the routine used to create a decomposition of fields for the shell DM

    916:    Logically Collective on dm

    918:    Input Arguments
    919: +  dm - the shell DM
    920: -  decomp - the routine to create the decomposition

    922:    Level: advanced

    924: .seealso: DMCreateFieldDecomposition(), DMShellSetContext(), DMShellGetContext()
    925: @*/
    926: PetscErrorCode DMShellSetCreateFieldDecomposition(DM dm, PetscErrorCode (*decomp)(DM,PetscInt*,char***, IS**,DM**))
    927: {
    929:   PetscBool      isshell;

    933:   PetscObjectTypeCompare((PetscObject)dm,DMSHELL,&isshell);
    934:   if (!isshell) return(0);
    935:   dm->ops->createfielddecomposition = decomp;
    936:   return(0);
    937: }

    939: /*@C
    940:    DMShellSetCreateDomainDecomposition - Set the routine used to create a domain decomposition for the shell DM

    942:    Logically Collective on dm

    944:    Input Arguments
    945: +  dm - the shell DM
    946: -  decomp - the routine to create the decomposition

    948:    Level: advanced

    950: .seealso: DMCreateDomainDecomposition(), DMShellSetContext(), DMShellGetContext()
    951: @*/
    952: PetscErrorCode DMShellSetCreateDomainDecomposition(DM dm, PetscErrorCode (*decomp)(DM,PetscInt*,char***, IS**,IS**,DM**))
    953: {
    955:   PetscBool      isshell;

    959:   PetscObjectTypeCompare((PetscObject)dm,DMSHELL,&isshell);
    960:   if (!isshell) return(0);
    961:   dm->ops->createdomaindecomposition = decomp;
    962:   return(0);
    963: }

    965: /*@C
    966:    DMShellSetCreateDomainDecompositionScatters - Set the routine used to create the scatter contexts for domain decomposition with a shell DM

    968:    Logically Collective on dm

    970:    Input Arguments
    971: +  dm - the shell DM
    972: -  scatter - the routine to create the scatters

    974:    Level: advanced

    976: .seealso: DMCreateDomainDecompositionScatters(), DMShellSetContext(), DMShellGetContext()
    977: @*/
    978: PetscErrorCode DMShellSetCreateDomainDecompositionScatters(DM dm, PetscErrorCode (*scatter)(DM,PetscInt,DM*,VecScatter**,VecScatter**,VecScatter**))
    979: {
    981:   PetscBool      isshell;

    985:   PetscObjectTypeCompare((PetscObject)dm,DMSHELL,&isshell);
    986:   if (!isshell) return(0);
    987:   dm->ops->createddscatters = scatter;
    988:   return(0);
    989: }

    991: /*@C
    992:    DMShellSetCreateSubDM - Set the routine used to create a sub DM from the shell DM

    994:    Logically Collective on dm

    996:    Input Arguments
    997: +  dm - the shell DM
    998: -  subdm - the routine to create the decomposition

    1000:    Level: advanced

    1002: .seealso: DMCreateSubDM(), DMShellGetCreateSubDM(), DMShellSetContext(), DMShellGetContext()
    1003: @*/
    1004: PetscErrorCode DMShellSetCreateSubDM(DM dm, PetscErrorCode (*subdm)(DM,PetscInt,const PetscInt[],IS*,DM*))
    1005: {
    1007:   PetscBool      isshell;

    1011:   PetscObjectTypeCompare((PetscObject)dm,DMSHELL,&isshell);
    1012:   if (!isshell) return(0);
    1013:   dm->ops->createsubdm = subdm;
    1014:   return(0);
    1015: }

    1017: /*@C
    1018:    DMShellGetCreateSubDM - Get the routine used to create a sub DM from the shell DM

    1020:    Logically Collective on dm

    1022:    Input Argument:
    1023: +  dm - the shell DM

    1025:    Output Argument:
    1026: -  subdm - the routine to create the decomposition

    1028:    Level: advanced

    1030: .seealso: DMCreateSubDM(), DMShellSetCreateSubDM(), DMShellSetContext(), DMShellGetContext()
    1031: @*/
    1032: PetscErrorCode DMShellGetCreateSubDM(DM dm, PetscErrorCode (**subdm)(DM,PetscInt,const PetscInt[],IS*,DM*))
    1033: {
    1035:   PetscBool      isshell;

    1039:   PetscObjectTypeCompare((PetscObject)dm,DMSHELL,&isshell);
    1040:   if (!isshell) SETERRQ(PetscObjectComm((PetscObject)dm),PETSC_ERR_SUP,"Can only use with DMSHELL type DMs");
    1041:   *subdm = dm->ops->createsubdm;
    1042:   return(0);
    1043: }

    1045: static PetscErrorCode DMDestroy_Shell(DM dm)
    1046: {
    1048:   DM_Shell       *shell = (DM_Shell*)dm->data;

    1051:   MatDestroy(&shell->A);
    1052:   VecDestroy(&shell->Xglobal);
    1053:   VecDestroy(&shell->Xlocal);
    1054:   VecScatterDestroy(&shell->gtol);
    1055:   VecScatterDestroy(&shell->ltog);
    1056:   VecScatterDestroy(&shell->ltol);
    1057:   /* This was originally freed in DMDestroy(), but that prevents reference counting of backend objects */
    1058:   PetscFree(shell);
    1059:   return(0);
    1060: }

    1062: static PetscErrorCode DMView_Shell(DM dm,PetscViewer v)
    1063: {
    1065:   DM_Shell       *shell = (DM_Shell*)dm->data;

    1068:   VecView(shell->Xglobal,v);
    1069:   return(0);
    1070: }

    1072: static PetscErrorCode DMLoad_Shell(DM dm,PetscViewer v)
    1073: {
    1075:   DM_Shell       *shell = (DM_Shell*)dm->data;

    1078:   VecCreate(PetscObjectComm((PetscObject)dm),&shell->Xglobal);
    1079:   VecLoad(shell->Xglobal,v);
    1080:   return(0);
    1081: }

    1083: PetscErrorCode DMCreateSubDM_Shell(DM dm, PetscInt numFields, const PetscInt fields[], IS *is, DM *subdm)
    1084: {

    1088:   if (subdm) {DMShellCreate(PetscObjectComm((PetscObject) dm), subdm);}
    1089:   DMCreateSectionSubDM(dm, numFields, fields, is, subdm);
    1090:   return(0);
    1091: }

    1093: PETSC_EXTERN PetscErrorCode DMCreate_Shell(DM dm)
    1094: {
    1096:   DM_Shell       *shell;

    1099:   PetscNewLog(dm,&shell);
    1100:   dm->data = shell;

    1102:   dm->ops->destroy            = DMDestroy_Shell;
    1103:   dm->ops->createglobalvector = DMCreateGlobalVector_Shell;
    1104:   dm->ops->createlocalvector  = DMCreateLocalVector_Shell;
    1105:   dm->ops->creatematrix       = DMCreateMatrix_Shell;
    1106:   dm->ops->view               = DMView_Shell;
    1107:   dm->ops->load               = DMLoad_Shell;
    1108:   dm->ops->globaltolocalbegin = DMGlobalToLocalBeginDefaultShell;
    1109:   dm->ops->globaltolocalend   = DMGlobalToLocalEndDefaultShell;
    1110:   dm->ops->localtoglobalbegin = DMLocalToGlobalBeginDefaultShell;
    1111:   dm->ops->localtoglobalend   = DMLocalToGlobalEndDefaultShell;
    1112:   dm->ops->localtolocalbegin  = DMLocalToLocalBeginDefaultShell;
    1113:   dm->ops->localtolocalend    = DMLocalToLocalEndDefaultShell;
    1114:   dm->ops->createsubdm        = DMCreateSubDM_Shell;
    1115:   DMSetMatType(dm,MATDENSE);
    1116:   return(0);
    1117: }

    1119: /*@
    1120:     DMShellCreate - Creates a shell DM object, used to manage user-defined problem data

    1122:     Collective

    1124:     Input Parameter:
    1125: .   comm - the processors that will share the global vector

    1127:     Output Parameters:
    1128: .   shell - the shell DM

    1130:     Level: advanced

    1132: .seealso DMDestroy(), DMCreateGlobalVector(), DMCreateLocalVector(), DMShellSetContext(), DMShellGetContext()
    1133: @*/
    1134: PetscErrorCode  DMShellCreate(MPI_Comm comm,DM *dm)
    1135: {

    1140:   DMCreate(comm,dm);
    1141:   DMSetType(*dm,DMSHELL);
    1142:   DMSetUp(*dm);
    1143:   return(0);
    1144: }