OvmfPkg/XenBusDxe: Add XenStore function into the XenBus protocol

Change in V3:
- Have XenStoreWaitWatch/XenBusWaitForWatch return a XENSTORE_STATUS
  instead of VOID.
- Add description of the introducted member of the protocol.

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Acked-by: Jordan Justen <jordan.l.justen@intel.com>
git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@16269 6f19259b-4bc3-4df7-8a09-765794883524

diff --git a/OvmfPkg/Include/Protocol/XenBus.h b/OvmfPkg/Include/Protocol/XenBus.h
index 565d491db697a9831879b157f88e7132899ca73d..5693b3f28436846664093dc045a5bf8dbce4a6b6 100644 (file)
--- a/OvmfPkg/Include/Protocol/XenBus.h
+++ b/OvmfPkg/Include/Protocol/XenBus.h
@@ -68,6 +68,136 @@ typedef enum {
 /// Function prototypes\r
 ///\r
 \r
+/**\r
+  Get the contents of the node Node of the PV device. Returns the contents in\r
+  *Result which should be freed after use.\r
+\r
+  @param This           A pointer to XENBUS_PROTOCOL instance.\r
+  @param Transaction    The XenStore transaction covering this request.\r
+  @param Node           The basename of the file to read.\r
+  @param Result         The returned contents from this file.\r
+\r
+  @return  On success, XENSTORE_STATUS_SUCCESS. Otherwise an errno value\r
+           indicating the type of failure.\r
+\r
+  @note The results buffer is malloced and should be free'd by the\r
+        caller.\r
+**/\r
+typedef\r
+XENSTORE_STATUS\r
+(EFIAPI *XENBUS_XS_READ)(\r
+  IN  XENBUS_PROTOCOL       *This,\r
+  IN  XENSTORE_TRANSACTION  Transaction,\r
+  IN  CONST CHAR8           *Node,\r
+  OUT VOID                  **Result\r
+  );\r
+\r
+/**\r
+  Get the contents of the node Node of the PV device's backend. Returns the\r
+  contents in *Result which should be freed after use.\r
+\r
+  @param This           A pointer to XENBUS_PROTOCOL instance.\r
+  @param Transaction    The XenStore transaction covering this request.\r
+  @param Node           The basename of the file to read.\r
+  @param Result         The returned contents from this file.\r
+\r
+  @return  On success, XENSTORE_STATUS_SUCCESS. Otherwise an errno value\r
+           indicating the type of failure.\r
+\r
+  @note The results buffer is malloced and should be free'd by the\r
+        caller.\r
+**/\r
+typedef\r
+XENSTORE_STATUS\r
+(EFIAPI *XENBUS_XS_BACKEND_READ)(\r
+  IN  XENBUS_PROTOCOL       *This,\r
+  IN  XENSTORE_TRANSACTION  Transaction,\r
+  IN  CONST CHAR8           *Node,\r
+  OUT VOID                  **Result\r
+  );\r
+\r
+/**\r
+  Print formatted write to a XenStore node.\r
+\r
+  @param This             A pointer to XENBUS_PROTOCOL instance.\r
+  @param Transaction      The XenStore transaction covering this request.\r
+  @param Directory        The dirname of the path to read.\r
+  @param Node             The basename of the path to read.\r
+  @param Format           AsciiSPrint format string followed by a variable number\r
+                          of arguments.\r
+\r
+  @return  On success, XENSTORE_STATUS_SUCCESS. Otherwise an errno value\r
+           indicating the type of write failure.\r
+**/\r
+typedef\r
+XENSTORE_STATUS\r
+(EFIAPI *XENBUS_XS_PRINTF) (\r
+  IN XENBUS_PROTOCOL        *This,\r
+  IN XENSTORE_TRANSACTION   Transaction,\r
+  IN CONST CHAR8            *Directory,\r
+  IN CONST CHAR8            *Node,\r
+  IN CONST CHAR8            *Format,\r
+  ...\r
+  );\r
+\r
+/**\r
+  Remove a node or directory (directories must be empty) of the PV driver's\r
+  subdirectory.\r
+\r
+  @param This           A pointer to XENBUS_PROTOCOL instance.\r
+  @param Transaction    The XenStore transaction covering this request.\r
+  @param Node           The basename of the node to remove.\r
+\r
+  @return  On success, XENSTORE_STATUS_SUCCESS. Otherwise an errno value\r
+           indicating the type of failure.\r
+**/\r
+typedef\r
+XENSTORE_STATUS\r
+(EFIAPI *XENBUS_XS_REMOVE) (\r
+  IN XENBUS_PROTOCOL        *This,\r
+  IN XENSTORE_TRANSACTION   Transaction,\r
+  IN CONST CHAR8            *Node\r
+  );\r
+\r
+/**\r
+  Start a transaction.\r
+\r
+  Changes by others will not be seen during the lifetime of this\r
+  transaction, and changes will not be visible to others until it\r
+  is committed (XsTransactionEnd).\r
+\r
+  @param This         A pointer to XENBUS_PROTOCOL instance.\r
+  @param Transaction  The returned transaction.\r
+\r
+  @return  On success, XENSTORE_STATUS_SUCCESS. Otherwise an errno value\r
+           indicating the type of failure.\r
+**/\r
+typedef\r
+XENSTORE_STATUS\r
+(EFIAPI *XENBUS_XS_TRANSACTION_START)(\r
+  IN  XENBUS_PROTOCOL       *This,\r
+  OUT XENSTORE_TRANSACTION  *Transaction\r
+  );\r
+\r
+/**\r
+  End a transaction.\r
+\r
+  @param This         A pointer to XENBUS_PROTOCOL instance.\r
+  @param Transaction  The transaction to end/commit.\r
+  @param Abort        If TRUE, the transaction is discarded\r
+                      instead of committed.\r
+\r
+  @return  On success, XENSTORE_STATUS_SUCCESS. Otherwise an errno value\r
+           indicating the type of failure.\r
+**/\r
+typedef\r
+XENSTORE_STATUS\r
+(EFIAPI *XENBUS_XS_TRANSACTION_END) (\r
+  IN XENBUS_PROTOCOL        *This,\r
+  IN XENSTORE_TRANSACTION   Transaction,\r
+  IN BOOLEAN                Abort\r
+  );\r
+\r
 /**\r
   Grant access to the page Frame to the domain DomainId.\r
 \r
@@ -101,6 +231,83 @@ EFI_STATUS
   IN grant_ref_t      Ref\r
   );\r
 \r
+/**\r
+  Register a XenStore watch.\r
+\r
+  XenStore watches allow a client to wait for changes to an object in the\r
+  XenStore.\r
+\r
+  @param This       A pointer to the XENBUS_PROTOCOL.\r
+  @param Node       The basename of the path to watch.\r
+  @param Token      A token.\r
+\r
+  @return  On success, XENSTORE_STATUS_SUCCESS. Otherwise an errno value\r
+           indicating the type of write failure.  EEXIST errors from the\r
+           XenStore are supressed, allowing multiple, physically different,\r
+           xenbus_watch objects, to watch the same path in the XenStore.\r
+**/\r
+typedef\r
+XENSTORE_STATUS\r
+(EFIAPI *XENBUS_REGISTER_WATCH) (\r
+  IN  XENBUS_PROTOCOL *This,\r
+  IN  CONST CHAR8     *Node,\r
+  OUT VOID            **Token\r
+  );\r
+\r
+/**\r
+  Register a XenStore watch on a backend's node.\r
+\r
+  XenStore watches allow a client to wait for changes to an object in the\r
+  XenStore.\r
+\r
+  @param This       A pointer to the XENBUS_PROTOCOL.\r
+  @param Node       The basename of the path to watch.\r
+  @param Token      A token.\r
+\r
+  @return  On success, XENSTORE_STATUS_SUCCESS. Otherwise an errno value\r
+           indicating the type of write failure.  EEXIST errors from the\r
+           XenStore are supressed, allowing multiple, physically different,\r
+           xenbus_watch objects, to watch the same path in the XenStore.\r
+**/\r
+typedef\r
+XENSTORE_STATUS\r
+(EFIAPI *XENBUS_REGISTER_WATCH_BACKEND) (\r
+  IN  XENBUS_PROTOCOL *This,\r
+  IN  CONST CHAR8     *Node,\r
+  OUT VOID            **Token\r
+  );\r
+\r
+/**\r
+  Unregister a XenStore watch.\r
+\r
+  @param This   A pointer to the XENBUS_PROTOCOL.\r
+  @param Token  An token previously returned by a successful\r
+                call to RegisterWatch ().\r
+**/\r
+typedef\r
+VOID\r
+(EFIAPI *XENBUS_UNREGISTER_WATCH) (\r
+  IN XENBUS_PROTOCOL  *This,\r
+  IN VOID             *Token\r
+  );\r
+\r
+/**\r
+  Block until the node watch by Token change.\r
+\r
+  @param This   A pointer to the XENBUS_PROTOCOL.\r
+  @param Token  An token previously returned by a successful\r
+                call to RegisterWatch or RegisterWatchBackend.\r
+\r
+  @return  On success, XENSTORE_STATUS_SUCCESS. Otherwise an errno value\r
+           indicating the type of failure.\r
+**/\r
+typedef\r
+XENSTORE_STATUS\r
+(EFIAPI *XENBUS_WAIT_FOR_WATCH) (\r
+  IN XENBUS_PROTOCOL  *This,\r
+  IN VOID             *Token\r
+  );\r
+\r
 \r
 ///\r
 /// Protocol structure\r
@@ -109,11 +316,27 @@ EFI_STATUS
 /// should not be used outside of the EDK II tree.\r
 ///\r
 struct _XENBUS_PROTOCOL {\r
+  XENBUS_XS_READ                XsRead;\r
+  XENBUS_XS_BACKEND_READ        XsBackendRead;\r
+  XENBUS_XS_PRINTF              XsPrintf;\r
+  XENBUS_XS_REMOVE              XsRemove;\r
+  XENBUS_XS_TRANSACTION_START   XsTransactionStart;\r
+  XENBUS_XS_TRANSACTION_END     XsTransactionEnd;\r
+\r
   XENBUS_GRANT_ACCESS           GrantAccess;\r
   XENBUS_GRANT_END_ACCESS       GrantEndAccess;\r
+\r
+  XENBUS_REGISTER_WATCH         RegisterWatch;\r
+  XENBUS_REGISTER_WATCH_BACKEND RegisterWatchBackend;\r
+  XENBUS_UNREGISTER_WATCH       UnregisterWatch;\r
+  XENBUS_WAIT_FOR_WATCH         WaitForWatch;\r
   //\r
   // Protocol data fields\r
   //\r
+  CONST CHAR8                   *Type;\r
+  UINT16                        DeviceId;\r
+  CONST CHAR8                   *Node;\r
+  CONST CHAR8                   *Backend;\r
 };\r
 \r
 extern EFI_GUID gXenBusProtocolGuid;\r

diff --git a/OvmfPkg/XenBusDxe/XenStore.c b/OvmfPkg/XenBusDxe/XenStore.c
index 4b99c9ca1fd8b772a2aa6d5b2303e1b902d64b84..aed6b141bdcd88c5ab1389d5b684f9a0031e7761 100644 (file)
--- a/OvmfPkg/XenBusDxe/XenStore.c
+++ b/OvmfPkg/XenBusDxe/XenStore.c
@@ -941,6 +941,46 @@ XenStoreUnwatch (
   return XenStoreTalkv (XST_NIL, XS_UNWATCH, WriteRequest, 2, NULL, NULL);\r
 }\r
 \r
+STATIC\r
+XENSTORE_STATUS\r
+XenStoreWaitWatch (\r
+  VOID *Token\r
+  )\r
+{\r
+  XENSTORE_MESSAGE *Message;\r
+  LIST_ENTRY *Entry = NULL;\r
+  LIST_ENTRY *Last = NULL;\r
+  XENSTORE_STATUS Status;\r
+\r
+  while (TRUE) {\r
+    EfiAcquireLock (&xs.WatchEventsLock);\r
+    if (IsListEmpty (&xs.WatchEvents) ||\r
+        Last == GetFirstNode (&xs.WatchEvents)) {\r
+      EfiReleaseLock (&xs.WatchEventsLock);\r
+      Status = XenStoreProcessMessage ();\r
+      if (Status != XENSTORE_STATUS_SUCCESS && Status != XENSTORE_STATUS_EAGAIN) {\r
+        return Status;\r
+      }\r
+      continue;\r
+    }\r
+\r
+    for (Entry = GetFirstNode (&xs.WatchEvents);\r
+         Entry != Last && !IsNull (&xs.WatchEvents, Entry);\r
+         Entry = GetNextNode (&xs.WatchEvents, Entry)) {\r
+      Message = XENSTORE_MESSAGE_FROM_LINK (Entry);\r
+      if (Message->u.Watch.Handle == Token) {\r
+        RemoveEntryList (Entry);\r
+        EfiReleaseLock (&xs.WatchEventsLock);\r
+        FreePool(Message->u.Watch.Vector);\r
+        FreePool(Message);\r
+        return XENSTORE_STATUS_SUCCESS;\r
+      }\r
+    }\r
+    Last = GetFirstNode (&xs.WatchEvents);\r
+    EfiReleaseLock (&xs.WatchEventsLock);\r
+  }\r
+}\r
+\r
 VOID\r
 EFIAPI\r
 NotifyEventChannelCheckForEvent (\r
@@ -1384,3 +1424,127 @@ XenStoreUnregisterWatch (
   FreePool (Watch->Node);\r
   FreePool (Watch);\r
 }\r
+\r
+\r
+//\r
+// XENBUS protocol\r
+//\r
+\r
+XENSTORE_STATUS\r
+EFIAPI\r
+XenBusWaitForWatch (\r
+  IN XENBUS_PROTOCOL *This,\r
+  IN VOID *Token\r
+  )\r
+{\r
+  return XenStoreWaitWatch (Token);\r
+}\r
+\r
+XENSTORE_STATUS\r
+EFIAPI\r
+XenBusXenStoreRead (\r
+  IN  XENBUS_PROTOCOL       *This,\r
+  IN  XENSTORE_TRANSACTION  Transaction,\r
+  IN  CONST CHAR8           *Node,\r
+  OUT VOID                  **Value\r
+  )\r
+{\r
+  return XenStoreRead (Transaction, This->Node, Node, NULL, Value);\r
+}\r
+\r
+XENSTORE_STATUS\r
+EFIAPI\r
+XenBusXenStoreBackendRead (\r
+  IN  XENBUS_PROTOCOL       *This,\r
+  IN  XENSTORE_TRANSACTION  Transaction,\r
+  IN  CONST CHAR8           *Node,\r
+  OUT VOID                  **Value\r
+  )\r
+{\r
+  return XenStoreRead (Transaction, This->Backend, Node, NULL, Value);\r
+}\r
+\r
+XENSTORE_STATUS\r
+EFIAPI\r
+XenBusXenStoreRemove (\r
+  IN XENBUS_PROTOCOL        *This,\r
+  IN XENSTORE_TRANSACTION   Transaction,\r
+  IN const char             *Node\r
+  )\r
+{\r
+  return XenStoreRemove (Transaction, This->Node, Node);\r
+}\r
+\r
+XENSTORE_STATUS\r
+EFIAPI\r
+XenBusXenStoreTransactionStart (\r
+  IN  XENBUS_PROTOCOL       *This,\r
+  OUT XENSTORE_TRANSACTION  *Transaction\r
+  )\r
+{\r
+  return XenStoreTransactionStart (Transaction);\r
+}\r
+\r
+XENSTORE_STATUS\r
+EFIAPI\r
+XenBusXenStoreTransactionEnd (\r
+  IN XENBUS_PROTOCOL        *This,\r
+  IN XENSTORE_TRANSACTION   Transaction,\r
+  IN BOOLEAN                Abort\r
+  )\r
+{\r
+  return XenStoreTransactionEnd (Transaction, Abort);\r
+}\r
+\r
+XENSTORE_STATUS\r
+EFIAPI\r
+XenBusXenStoreSPrint (\r
+  IN XENBUS_PROTOCOL        *This,\r
+  IN XENSTORE_TRANSACTION   Transaction,\r
+  IN CONST CHAR8            *DirectoryPath,\r
+  IN CONST CHAR8            *Node,\r
+  IN CONST CHAR8            *FormatString,\r
+  ...\r
+  )\r
+{\r
+  VA_LIST Marker;\r
+  XENSTORE_STATUS Status;\r
+\r
+  VA_START (Marker, FormatString);\r
+  Status = XenStoreVSPrint (Transaction, DirectoryPath, Node, FormatString, Marker);\r
+  VA_END (Marker);\r
+\r
+  return Status;\r
+}\r
+\r
+XENSTORE_STATUS\r
+EFIAPI\r
+XenBusRegisterWatch (\r
+  IN  XENBUS_PROTOCOL *This,\r
+  IN  CONST CHAR8     *Node,\r
+  OUT VOID            **Token\r
+  )\r
+{\r
+  return XenStoreRegisterWatch (This->Node, Node, (XENSTORE_WATCH **) Token);\r
+}\r
+\r
+XENSTORE_STATUS\r
+EFIAPI\r
+XenBusRegisterWatchBackend (\r
+  IN  XENBUS_PROTOCOL *This,\r
+  IN  CONST CHAR8     *Node,\r
+  OUT VOID            **Token\r
+  )\r
+{\r
+  return XenStoreRegisterWatch (This->Backend, Node, (XENSTORE_WATCH **) Token);\r
+}\r
+\r
+VOID\r
+EFIAPI\r
+XenBusUnregisterWatch (\r
+  IN XENBUS_PROTOCOL  *This,\r
+  IN VOID             *Token\r
+  )\r
+{\r
+  XenStoreUnregisterWatch ((XENSTORE_WATCH *) Token);\r
+}\r

diff --git a/OvmfPkg/XenBusDxe/XenStore.h b/OvmfPkg/XenBusDxe/XenStore.h
index 1503ed0473eefd3bf6b5252be65a453e494dc2ad..9020411f6a11767426afe05fe2b00783166143df 100644 (file)
--- a/OvmfPkg/XenBusDxe/XenStore.h
+++ b/OvmfPkg/XenBusDxe/XenStore.h
@@ -289,4 +289,91 @@ XenStoreDeinit (
   IN XENBUS_DEVICE *Dev\r
   );\r
 \r
+\r
+//\r
+// XENBUS protocol\r
+//\r
+\r
+XENSTORE_STATUS\r
+EFIAPI\r
+XenBusWaitForWatch (\r
+  IN XENBUS_PROTOCOL *This,\r
+  IN VOID *Token\r
+  );\r
+\r
+XENSTORE_STATUS\r
+EFIAPI\r
+XenBusXenStoreRead (\r
+  IN  XENBUS_PROTOCOL       *This,\r
+  IN  XENSTORE_TRANSACTION  Transaction,\r
+  IN  CONST CHAR8           *Node,\r
+  OUT VOID                  **Value\r
+  );\r
+\r
+XENSTORE_STATUS\r
+EFIAPI\r
+XenBusXenStoreBackendRead (\r
+  IN  XENBUS_PROTOCOL       *This,\r
+  IN  XENSTORE_TRANSACTION  Transaction,\r
+  IN  CONST CHAR8           *Node,\r
+  OUT VOID                  **Value\r
+  );\r
+\r
+XENSTORE_STATUS\r
+EFIAPI\r
+XenBusXenStoreRemove (\r
+  IN XENBUS_PROTOCOL        *This,\r
+  IN XENSTORE_TRANSACTION   Transaction,\r
+  IN CONST CHAR8            *Node\r
+  );\r
+\r
+XENSTORE_STATUS\r
+EFIAPI\r
+XenBusXenStoreTransactionStart (\r
+  IN  XENBUS_PROTOCOL       *This,\r
+  OUT XENSTORE_TRANSACTION  *Transaction\r
+  );\r
+\r
+XENSTORE_STATUS\r
+EFIAPI\r
+XenBusXenStoreTransactionEnd (\r
+  IN XENBUS_PROTOCOL        *This,\r
+  IN XENSTORE_TRANSACTION   Transaction,\r
+  IN BOOLEAN                Abort\r
+  );\r
+\r
+XENSTORE_STATUS\r
+EFIAPI\r
+XenBusXenStoreSPrint (\r
+  IN XENBUS_PROTOCOL        *This,\r
+  IN XENSTORE_TRANSACTION   Transaction,\r
+  IN CONST CHAR8            *DirectoryPath,\r
+  IN CONST CHAR8            *Node,\r
+  IN CONST CHAR8            *FormatString,\r
+  ...\r
+  );\r
+\r
+XENSTORE_STATUS\r
+EFIAPI\r
+XenBusRegisterWatch (\r
+  IN  XENBUS_PROTOCOL *This,\r
+  IN  CONST CHAR8     *Node,\r
+  OUT VOID            **Token\r
+  );\r
+\r
+XENSTORE_STATUS\r
+EFIAPI\r
+XenBusRegisterWatchBackend (\r
+  IN  XENBUS_PROTOCOL *This,\r
+  IN  CONST CHAR8     *Node,\r
+  OUT VOID            **Token\r
+  );\r
+\r
+VOID\r
+EFIAPI\r
+XenBusUnregisterWatch (\r
+  IN XENBUS_PROTOCOL  *This,\r
+  IN VOID             *Token\r
+  );\r
+\r
 #endif /* _XEN_XENSTORE_XENSTOREVAR_H */\r