Kernel/VFS - Clean up handle save+restore code
authorJohn Hodge <[email protected]>
Sun, 22 Sep 2013 11:08:36 +0000 (19:08 +0800)
committerJohn Hodge <[email protected]>
Sun, 22 Sep 2013 11:08:36 +0000 (19:08 +0800)
KernelLand/Kernel/vfs/handle.c

index 6173c29..db79933 100644 (file)
@@ -174,7 +174,6 @@ void VFS_CloseAllUserHandles(void)
 void *VFS_SaveHandles(int NumFDs, int *FDs)
 {
        tVFS_Handle     *ret;
-        int    i;
         int    max_handles = *Threads_GetMaxFD();
        
        // Check if this process has any handles
@@ -190,32 +189,42 @@ void *VFS_SaveHandles(int NumFDs, int *FDs)
                NumFDs = max_handles;
 
        // Take copies of the handles
-       for( i = 0; i < NumFDs; i ++ )
+       if( FDs == NULL ) {
+               memcpy(ret, gaUserHandles, NumFDs * sizeof(tVFS_Handle));
+       }
+       else
        {
-               tVFS_Handle     *h;
-               if( FDs == NULL )
-                       h = &gaUserHandles[i];
-               else if( FDs[i] == -1 )
-               {
-                       Log_Warning("VFS", "VFS_SaveHandles - Slot %i error FD (-1), ignorning", i);
-                       memset(&ret[i], 0, sizeof(tVFS_Handle));
-                       continue ;
-               }
-               else
+               for( int i = 0; i < NumFDs; i ++ )
                {
-                       h = VFS_GetHandle(FDs[i] & (VFS_KERNEL_FLAG - 1));
+                       if( FDs[i] < -1 )
+                       {
+                               Log_Warning("VFS", "VFS_SaveHandles - Slot %i error FD (%i<0), ignorning",
+                                       i, FDs[i]);
+                               memset(&ret[i], 0, sizeof(tVFS_Handle));
+                               continue ;
+                       }
+                       
+                       int fd = FDs[i] & (VFS_KERNEL_FLAG - 1);
+                       tVFS_Handle *h = VFS_GetHandle(fd);
                        if(!h) {
-                               Log_Warning("VFS", "VFS_SaveHandles - Invalid FD %i",
-                                       FDs[i] & (VFS_KERNEL_FLAG - 1) );
+                               Log_Warning("VFS", "VFS_SaveHandles - Invalid FD 0x%x (%i) in slot %i",
+                                       fd, FDs[i], i );
                                free(ret);
                                return NULL;
                        }
+//                     Log("%i: Duplicate FD %i (%p)", i, fd, h->Node);
+                       memcpy( &ret[i], h, sizeof(tVFS_Handle) );
                }
-               memcpy( &ret[i], h, sizeof(tVFS_Handle) );
-               
+       }
+       
+       // Reference nodes/mounts
+       for( int i = 0; i < NumFDs; i ++ )
+       {
+               tVFS_Handle *h = &ret[i];
                // Reference node
                if( !h->Node )
                        continue ;
+//             Debug("VFS_SaveHandles: %i %p", i, h->Node);
                _ReferenceNode(h->Node);
                h->Mount->OpenHandleCount ++;
        }       
@@ -226,45 +235,55 @@ void *VFS_SaveHandles(int NumFDs, int *FDs)
 void VFS_RestoreHandles(int NumFDs, void *Handles)
 {
        tVFS_Handle     *handles = Handles;
-        int    i;
+        int    max_handles = *Threads_GetMaxFD();
 
        // NULL = nothing to do
        if( !Handles )
                return ;        
 
-       // Check if there is already a set of handles
-       if( MM_GetPhysAddr( gaUserHandles ) != 0 )
-               return ;
-       
-       
-       // Allocate user handle area
+       // Allocate user handle area (and dereference existing handles)
+       for( int i = 0; i < NumFDs; i ++ )
        {
-               Uint    addr, size;
-                int    max_handles = *Threads_GetMaxFD();
-               size = max_handles * sizeof(tVFS_Handle);
-               for(addr = 0; addr < size; addr += 0x1000)
+               tVFS_Handle *h = &gaUserHandles[i];
+               
+               if( !MM_GetPhysAddr(h) )
                {
-                       if( !MM_Allocate( (tVAddr)gaUserHandles + addr ) )
+                       if( !MM_Allocate( (tVAddr)h & ~(PAGE_SIZE-1) ) ) 
                        {
-                               Warning("OOM - VFS_AllocHandle");
-                               Threads_Exit(0, 0xFF);  // Terminate user
+                               // OOM?
                        }
                }
-               memset( gaUserHandles, 0, size );
+               // Safe to dereference, as Threads_CloneTCB references handles
+               #if 1
+               else
+               {
+                       if(h->Node)
+                       {
+                               _CloseNode(h->Node);
+                               h->Mount->OpenHandleCount --;
+                       }
+               }
+               #endif
        }
        
+       // Clean up existing
        // Restore handles
        memcpy( gaUserHandles, handles, NumFDs * sizeof(tVFS_Handle) );
        // Reference when copied
-       for( i = 0; i < NumFDs; i ++ )
+       for( int i = 0; i < NumFDs; i ++ )
        {
-               tVFS_Handle     *h = &handles[i];
+               tVFS_Handle     *h = &gaUserHandles[i];
        
                if( !h->Node )
                        continue ;
+//             Debug("VFS_RestoreHandles: %i %p", i, h->Node);
                _ReferenceNode(h->Node);
                h->Mount->OpenHandleCount ++;
        }
+       for( int i = NumFDs; i < max_handles; i ++ )
+       {
+               gaUserHandles[i].Node = NULL;
+       }
 }
 
 void VFS_FreeSavedHandles(int NumFDs, void *Handles)

UCC git Repository :: git.ucc.asn.au