Kernel/vfs/handle.c

   1 /*
   2  * Acess2 VFS
   3  * - AllocHandle, GetHandle
   4  */
   5 #define DEBUG   0
   6 #include <acess.h>
   7 #include <mm_virt.h>
   8 #include "vfs.h"
   9 #include "vfs_int.h"
  10 #include "vfs_ext.h"
  11 #include <threads.h>    // GetMaxFD
  12
  13 // === CONSTANTS ===
  14 #define MAX_KERNEL_FILES        128
  15
  16 // === PROTOTYPES ===
  17 #if 0
  18 tVFS_Handle     *VFS_GetHandle(int FD);
  19 #endif
  20  int    VFS_AllocHandle(int FD, tVFS_Node *Node, int Mode);
  21
  22 // === GLOBALS ===
  23 tVFS_Handle     *gaUserHandles = (void*)MM_PPD_HANDLES;
  24 tVFS_Handle     *gaKernelHandles = (void*)MM_KERNEL_VFS;
  25
  26 // === CODE ===
  27 /**
  28  * \fn tVFS_Handle *VFS_GetHandle(int FD)
  29  * \brief Gets a pointer to the handle information structure
  30  */
  31 tVFS_Handle *VFS_GetHandle(int FD)
  32 {
  33         tVFS_Handle     *h;
  34
  35         //Log_Debug("VFS", "VFS_GetHandle: (FD=0x%x)", FD);
  36
  37         if(FD < 0)      return NULL;
  38
  39         if(FD & VFS_KERNEL_FLAG) {
  40                 FD &= (VFS_KERNEL_FLAG - 1);
  41                 if(FD >= MAX_KERNEL_FILES)      return NULL;
  42                 h = &gaKernelHandles[ FD ];
  43         } else {
  44                 if(FD >= *Threads_GetMaxFD())   return NULL;
  45                 h = &gaUserHandles[ FD ];
  46         }
  47
  48         if(h->Node == NULL)     return NULL;
  49         //Log_Debug("VFS", "VFS_GetHandle: RETURN %p", h);
  50         return h;
  51 }
  52
  53 int VFS_AllocHandle(int bIsUser, tVFS_Node *Node, int Mode)
  54 {
  55          int    i;
  56
  57         // Check for a user open
  58         if(bIsUser)
  59         {
  60                  int    max_handles = *Threads_GetMaxFD();
  61                 // Allocate Buffer
  62                 if( MM_GetPhysAddr( (tVAddr)gaUserHandles ) == 0 )
  63                 {
  64                         Uint    addr, size;
  65                         size = max_handles * sizeof(tVFS_Handle);
  66                         for(addr = 0; addr < size; addr += 0x1000)
  67                         {
  68                                 if( !MM_Allocate( (tVAddr)gaUserHandles + addr ) )
  69                                 {
  70                                         Warning("OOM - VFS_AllocHandle");
  71                                         Threads_Exit(0, 0xFF);  // Terminate user
  72                                 }
  73                         }
  74                         memset( gaUserHandles, 0, size );
  75                 }
  76                 // Get a handle
  77                 for( i = 0; i < max_handles; i ++ )
  78                 {
  79                         if(gaUserHandles[i].Node)       continue;
  80                         gaUserHandles[i].Node = Node;
  81                         gaUserHandles[i].Position = 0;
  82                         gaUserHandles[i].Mode = Mode;
  83                         return i;
  84                 }
  85         }
  86         else
  87         {
  88                 // Allocate space if not already
  89                 if( MM_GetPhysAddr( (tVAddr)gaKernelHandles ) == 0 )
  90                 {
  91                         Uint    addr, size;
  92                         size = MAX_KERNEL_FILES * sizeof(tVFS_Handle);
  93                         for(addr = 0; addr < size; addr += 0x1000)
  94                         {
  95                                 if( !MM_Allocate( (tVAddr)gaKernelHandles + addr ) )
  96                                 {
  97                                         Panic("OOM - VFS_AllocHandle");
  98                                         Threads_Exit(0, 0xFF);  // Terminate application (get some space back)
  99                                 }
 100                         }
 101                         memset( gaKernelHandles, 0, size );
 102                 }
 103                 // Get a handle
 104                 for(i=0;i<MAX_KERNEL_FILES;i++)
 105                 {
 106                         if(gaKernelHandles[i].Node)     continue;
 107                         gaKernelHandles[i].Node = Node;
 108                         gaKernelHandles[i].Position = 0;
 109                         gaKernelHandles[i].Mode = Mode;
 110                         return i|VFS_KERNEL_FLAG;
 111                 }
 112         }
 113
 114         return -1;
 115 }