+++ /dev/null
-/*
- * Acess2 VFS
- * - Open, Close and ChDir
- */
-#define DEBUG 0
-#include <acess.h>
-#include <vfs.h>
-#include <vfs_ext.h>
-#include <vfs_int.h>
-
-#define MMAP_PAGES_PER_BLOCK 16
-
-// === STRUCTURES ===
-typedef struct sVFS_MMapPageBlock
-{
- tVFS_MMapPageBlock *Next;
- Uint64 BaseOffset; // Must be a multiple of MMAP_PAGES_PER_BLOCK*PAGE_SIZE
- tPAddr PhysAddrs[MMAP_PAGES_PER_BLOCK];
-} tVFS_MMapPageBlock;
-
-// === CODE ===
-void *VFS_MMap(int *ErrNo, void *DestHint, size_t Length, int Protection, int Flags, int FD, Uint64 Offset)
-{
- tVFS_Handle *h;
- void *mapping_dest;
- int npages, pagenum;
- tVFS_MMapPageBlock *pb, *prev;
-
- npages = ((Offset & (PAGE_SIZE-1)) + Length) / PAGE_SIZE;
- pagenum = Offset / PAGE_SIZE;
-
- mapping_dest = DestHint;
-
- // TODO: Locate space for the allocation
- if( Flags & MAP_ANONYMOUS )
- {
- MM_Allocate(mapping_dest);
- return mapping_dest;
- }
-
- h = VFS_GetHandle(FD);
- if( !h || !h->Node ) return NULL;
-
- // Search for existing mapping for each page
- // - Sorted list of 16 page blocks
- for(
- pb = h->Node->MMapInfo, prev = NULL;
- pb && pb->BaseOffset + MMAP_PAGES_PER_BLOCK < pagenum;
- prev = pb, pb = pb->Next
- );
-
- if( !pb || pb->BaseOffset > pagenum )
- {
- void *old_pb = pb;
- // Allocate if needed
- pb = malloc( sizeof(tVFS_MMapPageBlock) );
- if(!pb) return NULL;
- pb->Next = old_pb;
- pb->BaseOffset = pagenum - pagenum % MMAP_PAGES_PER_BLOCK;
- memset(pb->PhysAddrs, 0, sizeof(pb->PhysAddrs));
- if(prev)
- prev->Next = pb;
- else
- h->Node->MMapInfo = pb;
- }
-
- while( npages -- )
- {
- if( pb->PhysAddrs[pagenum - pb->BaseOffset] == 0 )
- {
- if( h->Node->MMap )
- h->Node->MMap(h->Node, pagenum*PAGE_SIZE, PAGE_SIZE, mapping_dest);
- else
- {
- // Allocate pages and read data
- MM_Allocate(mapping_dest);
- h->Node->Read(h->Node, pagenum*PAGE_SIZE, PAGE_SIZE, mapping_dest);
- }
- pb->PhysAddrs[pagenum -> pb->BaseOffset] = MM_GetPhysAddr( mapping_dest );
- }
- else
- {
- MM_Map( mapping_dest, pb->PhysAddrs[pagenum - pb->BaseOffset] );
- }
- pagenum ++;
- mapping_dest += PAGE_SIZE;
-
- // Roll on to next block if needed
- if(pagenum - pb->BaseOffset == MMAP_PAGES_PER_BLOCK)
- {
- if( pb->Next && pb->Next->BaseOffset == pagenum )
- pb = pb->Next;
- else
- {
- tVFS_MMapPageBlock *oldpb = pb;
- pb = malloc( sizeof(tVFS_MMapPageBlock) );
- pb->Next = oldpb->Next;
- pb->BaseOffset = pagenum;
- memset(pb->PhysAddrs, 0, sizeof(pb->PhysAddrs));
- oldpb->Next = pb;
- }
- pagenum = 0;
- }
- }
-
- return NULL;
-}
-
-int VFS_MUnmap(int *ErrNo, void *Addr, size_t Length)
-{
- return 0;
-}