tran_dmafree(9E)

NAME

     tran_dmafree - SCSI HBA DMA deallocation entry point

SYNOPSIS

     #include <sys/scsi/scsi.h>

      void  prefixtran_dmafree(struct  scsi_address  *ap,  struct
     scsi_pkt *pkt);

INTERFACE LEVEL

     Solaris architecture specific (Solaris DDI).

ARGUMENTS

     ap    A   pointer   to   a   scsi_address   structure.   See
           scsi_address(9S).

     pkt   A pointer to a scsi_pkt  structure. See scsi_pkt(9S).

DESCRIPTION

     The tran_dmafree() vector  in  the  scsi_hba_tran  structure
     must  be  initialized  during  the  HBA driver's attach() to
     point to an HBA entry point  to  be  called  when  a  target
     driver    calls   scsi_dmafree(9F).   See   attach(9E)   and
     scsi_hba_tran(9S).

     tran_dmafree() must deallocate any DMA resources  previously
     allocated  to  this   pkt  in  a  call to tran_init_pkt(9E).
     tran_dmafree() should not free the structure pointed  to  by
     pkt  itself.  Since  tran_destroy_pkt(9E) must also free DMA
     resources, it is important that the HBA driver  keeps  accu-
     rate  note  of  whether  scsi_pkt(9S)  structures  have  DMA
     resources allocated.

SEE ALSO

     attach(9E),     tran_destroy_pkt(9E),     tran_init_pkt(9E),
     scsi_dmafree(9F),    scsi_dmaget(9F),   scsi_hba_attach(9F),
     scsi_init_pkt(9F),   scsi_address(9S),    scsi_hba_tran(9S),
     scsi_pkt(9S)

     Writing Device Drivers

NOTES

     A target driver may call tran_dmafree() on packets for which
     no DMA resources were allocated.