MdeModulePkg/Core/PiSmmCore/Notify.c

   1 /** @file
   2   Support functions for UEFI protocol notification infrastructure.
   3
   4   Copyright (c) 2009 - 2018, Intel Corporation. All rights reserved.<BR>
   5   SPDX-License-Identifier: BSD-2-Clause-Patent
   6
   7 **/
   8
   9 #include "PiSmmCore.h"
  10
  11 /**
  12   Signal event for every protocol in protocol entry.
  13
  14   @param  Prot                   Protocol interface
  15
  16 **/
  17 VOID
  18 SmmNotifyProtocol (
  19   IN PROTOCOL_INTERFACE  *Prot
  20   )
  21 {
  22   PROTOCOL_ENTRY   *ProtEntry;
  23   PROTOCOL_NOTIFY  *ProtNotify;
  24   LIST_ENTRY       *Link;
  25
  26   ProtEntry = Prot->Protocol;
  27   for (Link=ProtEntry->Notify.ForwardLink; Link != &ProtEntry->Notify; Link=Link->ForwardLink) {
  28     ProtNotify = CR(Link, PROTOCOL_NOTIFY, Link, PROTOCOL_NOTIFY_SIGNATURE);
  29     ProtNotify->Function (&ProtEntry->ProtocolID, Prot->Interface, Prot->Handle);
  30   }
  31 }
  32
  33 /**
  34   Removes Protocol from the protocol list (but not the handle list).
  35
  36   @param  Handle                 The handle to remove protocol on.
  37   @param  Protocol               GUID of the protocol to be moved
  38   @param  Interface              The interface of the protocol
  39
  40   @return Protocol Entry
  41
  42 **/
  43 PROTOCOL_INTERFACE *
  44 SmmRemoveInterfaceFromProtocol (
  45   IN IHANDLE   *Handle,
  46   IN EFI_GUID  *Protocol,
  47   IN VOID      *Interface
  48   )
  49 {
  50   PROTOCOL_INTERFACE  *Prot;
  51   PROTOCOL_NOTIFY     *ProtNotify;
  52   PROTOCOL_ENTRY      *ProtEntry;
  53   LIST_ENTRY          *Link;
  54
  55   Prot = SmmFindProtocolInterface (Handle, Protocol, Interface);
  56   if (Prot != NULL) {
  57
  58     ProtEntry = Prot->Protocol;
  59
  60     //
  61     // If there's a protocol notify location pointing to this entry, back it up one
  62     //
  63     for(Link = ProtEntry->Notify.ForwardLink; Link != &ProtEntry->Notify; Link=Link->ForwardLink) {
  64       ProtNotify = CR(Link, PROTOCOL_NOTIFY, Link, PROTOCOL_NOTIFY_SIGNATURE);
  65
  66       if (ProtNotify->Position == &Prot->ByProtocol) {
  67         ProtNotify->Position = Prot->ByProtocol.BackLink;
  68       }
  69     }
  70
  71     //
  72     // Remove the protocol interface entry
  73     //
  74     RemoveEntryList (&Prot->ByProtocol);
  75   }
  76
  77   return Prot;
  78 }
  79
  80 /**
  81   Add a new protocol notification record for the request protocol.
  82
  83   @param  Protocol               The requested protocol to add the notify
  84                                  registration
  85   @param  Function               Points to the notification function
  86   @param  Registration           Returns the registration record
  87
  88   @retval EFI_SUCCESS            Successfully returned the registration record
  89                                  that has been added or unhooked
  90   @retval EFI_INVALID_PARAMETER  Protocol is NULL or Registration is NULL
  91   @retval EFI_OUT_OF_RESOURCES   Not enough memory resource to finish the request
  92   @retval EFI_NOT_FOUND          If the registration is not found when Function == NULL
  93
  94 **/
  95 EFI_STATUS
  96 EFIAPI
  97 SmmRegisterProtocolNotify (
  98   IN  CONST EFI_GUID     *Protocol,
  99   IN  EFI_SMM_NOTIFY_FN  Function,
 100   OUT VOID               **Registration
 101   )
 102 {
 103   PROTOCOL_ENTRY   *ProtEntry;
 104   PROTOCOL_NOTIFY  *ProtNotify;
 105   LIST_ENTRY       *Link;
 106   EFI_STATUS       Status;
 107
 108   if (Protocol == NULL || Registration == NULL) {
 109     return EFI_INVALID_PARAMETER;
 110   }
 111
 112   if (Function == NULL) {
 113     //
 114     // Get the protocol entry per Protocol
 115     //
 116     ProtEntry = SmmFindProtocolEntry ((EFI_GUID *) Protocol, FALSE);
 117     if (ProtEntry != NULL) {
 118       ProtNotify = (PROTOCOL_NOTIFY * )*Registration;
 119       for (Link = ProtEntry->Notify.ForwardLink;
 120            Link != &ProtEntry->Notify;
 121            Link = Link->ForwardLink) {
 122         //
 123         // Compare the notification record
 124         //
 125         if (ProtNotify == (CR(Link, PROTOCOL_NOTIFY, Link, PROTOCOL_NOTIFY_SIGNATURE))){
 126           //
 127           // If Registration is an existing registration, then unhook it
 128           //
 129           ProtNotify->Signature = 0;
 130           RemoveEntryList (&ProtNotify->Link);
 131           FreePool (ProtNotify);
 132           return EFI_SUCCESS;
 133         }
 134       }
 135     }
 136     //
 137     // If the registration is not found
 138     //
 139     return EFI_NOT_FOUND;
 140   }
 141
 142   ProtNotify = NULL;
 143
 144   //
 145   // Get the protocol entry to add the notification too
 146   //
 147   ProtEntry = SmmFindProtocolEntry ((EFI_GUID *) Protocol, TRUE);
 148   if (ProtEntry != NULL) {
 149     //
 150     // Find whether notification already exist
 151     //
 152     for (Link = ProtEntry->Notify.ForwardLink;
 153          Link != &ProtEntry->Notify;
 154          Link = Link->ForwardLink) {
 155
 156       ProtNotify = CR(Link, PROTOCOL_NOTIFY, Link, PROTOCOL_NOTIFY_SIGNATURE);
 157       if (CompareGuid (&ProtNotify->Protocol->ProtocolID, Protocol) &&
 158           (ProtNotify->Function == Function)) {
 159
 160         //
 161         // Notification already exist
 162         //
 163         *Registration = ProtNotify;
 164
 165         return EFI_SUCCESS;
 166       }
 167     }
 168
 169     //
 170     // Allocate a new notification record
 171     //
 172     ProtNotify = AllocatePool (sizeof(PROTOCOL_NOTIFY));
 173     if (ProtNotify != NULL) {
 174       ProtNotify->Signature = PROTOCOL_NOTIFY_SIGNATURE;
 175       ProtNotify->Protocol = ProtEntry;
 176       ProtNotify->Function = Function;
 177       //
 178       // Start at the ending
 179       //
 180       ProtNotify->Position = ProtEntry->Protocols.BackLink;
 181
 182       InsertTailList (&ProtEntry->Notify, &ProtNotify->Link);
 183     }
 184   }
 185
 186   //
 187   // Done.  If we have a protocol notify entry, then return it.
 188   // Otherwise, we must have run out of resources trying to add one
 189   //
 190   Status = EFI_OUT_OF_RESOURCES;
 191   if (ProtNotify != NULL) {
 192     *Registration = ProtNotify;
 193     Status = EFI_SUCCESS;
 194   }
 195   return Status;
 196 }