MdeModulePkg/Core/PiSmmCore/Notify.c

   1 /** @file
   2   Support functions for UEFI protocol notification infrastructure.
   3
   4   Copyright (c) 2009 - 2015, Intel Corporation. All rights reserved.<BR>
   5   This program and the accompanying materials are licensed and made available
   6   under the terms and conditions of the BSD License which accompanies this
   7   distribution.  The full text of the license may be found at
   8   http://opensource.org/licenses/bsd-license.php
   9
  10   THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  11   WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
  12
  13 **/
  14
  15 #include "PiSmmCore.h"
  16
  17 /**
  18   Signal event for every protocol in protocol entry.
  19
  20   @param  Prot                   Protocol interface
  21
  22 **/
  23 VOID
  24 SmmNotifyProtocol (
  25   IN PROTOCOL_INTERFACE  *Prot
  26   )
  27 {
  28   PROTOCOL_ENTRY   *ProtEntry;
  29   PROTOCOL_NOTIFY  *ProtNotify;
  30   LIST_ENTRY       *Link;
  31
  32   ProtEntry = Prot->Protocol;
  33   for (Link=ProtEntry->Notify.ForwardLink; Link != &ProtEntry->Notify; Link=Link->ForwardLink) {
  34     ProtNotify = CR(Link, PROTOCOL_NOTIFY, Link, PROTOCOL_NOTIFY_SIGNATURE);
  35     ProtNotify->Function (&ProtEntry->ProtocolID, Prot->Interface, Prot->Handle);
  36   }
  37 }
  38
  39 /**
  40   Removes Protocol from the protocol list (but not the handle list).
  41
  42   @param  Handle                 The handle to remove protocol on.
  43   @param  Protocol               GUID of the protocol to be moved
  44   @param  Interface              The interface of the protocol
  45
  46   @return Protocol Entry
  47
  48 **/
  49 PROTOCOL_INTERFACE *
  50 SmmRemoveInterfaceFromProtocol (
  51   IN IHANDLE   *Handle,
  52   IN EFI_GUID  *Protocol,
  53   IN VOID      *Interface
  54   )
  55 {
  56   PROTOCOL_INTERFACE  *Prot;
  57   PROTOCOL_NOTIFY     *ProtNotify;
  58   PROTOCOL_ENTRY      *ProtEntry;
  59   LIST_ENTRY          *Link;
  60
  61   Prot = SmmFindProtocolInterface (Handle, Protocol, Interface);
  62   if (Prot != NULL) {
  63
  64     ProtEntry = Prot->Protocol;
  65
  66     //
  67     // If there's a protocol notify location pointing to this entry, back it up one
  68     //
  69     for(Link = ProtEntry->Notify.ForwardLink; Link != &ProtEntry->Notify; Link=Link->ForwardLink) {
  70       ProtNotify = CR(Link, PROTOCOL_NOTIFY, Link, PROTOCOL_NOTIFY_SIGNATURE);
  71
  72       if (ProtNotify->Position == &Prot->ByProtocol) {
  73         ProtNotify->Position = Prot->ByProtocol.BackLink;
  74       }
  75     }
  76
  77     //
  78     // Remove the protocol interface entry
  79     //
  80     RemoveEntryList (&Prot->ByProtocol);
  81   }
  82
  83   return Prot;
  84 }
  85
  86 /**
  87   Add a new protocol notification record for the request protocol.
  88
  89   @param  Protocol               The requested protocol to add the notify
  90                                  registration
  91   @param  Function               Points to the notification function
  92   @param  Registration           Returns the registration record
  93
  94   @retval EFI_SUCCESS            Successfully returned the registration record
  95                                  that has been added or unhooked
  96   @retval EFI_INVALID_PARAMETER  Protocol is NULL or Registration is NULL
  97   @retval EFI_OUT_OF_RESOURCES   Not enough memory resource to finish the request
  98   @retval EFI_NOT_FOUND          If the registration is not found when Function == NULL
  99
 100 **/
 101 EFI_STATUS
 102 EFIAPI
 103 SmmRegisterProtocolNotify (
 104   IN  CONST EFI_GUID     *Protocol,
 105   IN  EFI_SMM_NOTIFY_FN  Function,
 106   OUT VOID               **Registration
 107   )
 108 {
 109   PROTOCOL_ENTRY   *ProtEntry;
 110   PROTOCOL_NOTIFY  *ProtNotify;
 111   LIST_ENTRY       *Link;
 112   EFI_STATUS       Status;
 113
 114   if (Protocol == NULL || Registration == NULL) {
 115     return EFI_INVALID_PARAMETER;
 116   }
 117
 118   if (Function == NULL) {
 119         //
 120     // Get the protocol entry per Protocol
 121     //
 122     ProtEntry = SmmFindProtocolEntry ((EFI_GUID *) Protocol, FALSE);
 123     if (ProtEntry != NULL) {
 124       ProtNotify = (PROTOCOL_NOTIFY * )*Registration;
 125       for (Link = ProtEntry->Notify.ForwardLink;
 126            Link != &ProtEntry->Notify;
 127            Link = Link->ForwardLink) {
 128         //
 129         // Compare the notification record
 130         //
 131         if (ProtNotify == (CR(Link, PROTOCOL_NOTIFY, Link, PROTOCOL_NOTIFY_SIGNATURE))){
 132           //
 133           // If Registration is an existing registration, then unhook it
 134           //
 135           ProtNotify->Signature = 0;
 136           RemoveEntryList (&ProtNotify->Link);
 137           FreePool (ProtNotify);
 138           return EFI_SUCCESS;
 139         }
 140       }
 141     }
 142     //
 143     // If the registration is not found
 144     //
 145     return EFI_NOT_FOUND;
 146   }
 147
 148   ProtNotify = NULL;
 149
 150   //
 151   // Get the protocol entry to add the notification too
 152   //
 153   ProtEntry = SmmFindProtocolEntry ((EFI_GUID *) Protocol, TRUE);
 154   if (ProtEntry != NULL) {
 155     //
 156     // Find whether notification already exist
 157     //
 158     for (Link = ProtEntry->Notify.ForwardLink;
 159          Link != &ProtEntry->Notify;
 160          Link = Link->ForwardLink) {
 161
 162       ProtNotify = CR(Link, PROTOCOL_NOTIFY, Link, PROTOCOL_NOTIFY_SIGNATURE);
 163       if (CompareGuid (&ProtNotify->Protocol->ProtocolID, Protocol) &&
 164           (ProtNotify->Function == Function)) {
 165
 166         //
 167         // Notification already exist
 168         //
 169         *Registration = ProtNotify;
 170
 171         return EFI_SUCCESS;
 172       }
 173     }
 174
 175     //
 176     // Allocate a new notification record
 177     //
 178     ProtNotify = AllocatePool (sizeof(PROTOCOL_NOTIFY));
 179     if (ProtNotify != NULL) {
 180       ProtNotify->Signature = PROTOCOL_NOTIFY_SIGNATURE;
 181       ProtNotify->Protocol = ProtEntry;
 182       ProtNotify->Function = Function;
 183       //
 184       // Start at the ending
 185       //
 186       ProtNotify->Position = ProtEntry->Protocols.BackLink;
 187
 188       InsertTailList (&ProtEntry->Notify, &ProtNotify->Link);
 189     }
 190   }
 191
 192   //
 193   // Done.  If we have a protocol notify entry, then return it.
 194   // Otherwise, we must have run out of resources trying to add one
 195   //
 196   Status = EFI_OUT_OF_RESOURCES;
 197   if (ProtNotify != NULL) {
 198     *Registration = ProtNotify;
 199     Status = EFI_SUCCESS;
 200   }
 201   return Status;
 202 }