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