X-Git-Url: https://git.ucc.asn.au/?a=blobdiff_plain;ds=sidebyside;f=KernelLand%2FKernel%2Fvfs%2Fmmap.c;h=9a7fa44b9da3312e541ba479cc42a4cd76aaafce;hb=c1b33e91984102c1aa9a2ffe19f02c315b481726;hp=b6d5c2d91921425bb8864cb04dd797e91776526a;hpb=3c3c26b58055f511af5b7f0c3ab22e83961c775f;p=tpg%2Facess2.git diff --git a/KernelLand/Kernel/vfs/mmap.c b/KernelLand/Kernel/vfs/mmap.c index b6d5c2d9..9a7fa44b 100644 --- a/KernelLand/Kernel/vfs/mmap.c +++ b/KernelLand/Kernel/vfs/mmap.c @@ -25,32 +25,40 @@ struct sVFS_MMapPageBlock // === PROTOTYPES === //void *VFS_MMap(void *DestHint, size_t Length, int Protection, int Flags, int FD, Uint64 Offset); void *VFS_MMap_Anon(void *Destination, size_t Length, Uint FlagsSet, Uint FlagsMask); +int VFS_MMap_MapPage(tVFS_Node *Node, unsigned int PageNum, tVFS_MMapPageBlock *pb, void *mapping_dest, unsigned int Protection); //int VFS_MUnmap(void *Addr, size_t Length); // === CODE === void *VFS_MMap(void *DestHint, size_t Length, int Protection, int Flags, int FD, Uint64 Offset) { - tVAddr mapping_base; - int npages, pagenum; - tVFS_MMapPageBlock *pb, *prev; - ENTER("pDestHint iLength xProtection xFlags xFD XOffset", DestHint, Length, Protection, Flags, FD, Offset); if( Flags & MMAP_MAP_ANONYMOUS ) Offset = (tVAddr)DestHint & 0xFFF; - npages = ((Offset & (PAGE_SIZE-1)) + Length + (PAGE_SIZE - 1)) / PAGE_SIZE; - pagenum = Offset / PAGE_SIZE; + unsigned int npages = ((Offset & (PAGE_SIZE-1)) + Length + (PAGE_SIZE - 1)) / PAGE_SIZE; + unsigned int pagenum = Offset / PAGE_SIZE; - mapping_base = (tVAddr)DestHint; - tPage *mapping_dest = (void*)(mapping_base & ~(PAGE_SIZE-1)); + tVAddr mapping_base = (tVAddr)DestHint; - if( DestHint == NULL ) + if( Flags & MMAP_MAP_FIXED ) + { + ASSERT( (Flags & MMAP_MAP_FIXED) && DestHint != NULL ); + // Keep and use the hint + // - TODO: Validate that the region pointed to by the hint is correct + } + else { - // TODO: Locate space for the allocation - LEAVE('n'); - return NULL; + Log_Warning("VFS", "MMap: TODO Handle non-fixed mappings"); + if( DestHint == NULL ) + { + // TODO: Locate space for the allocation + Log_Warning("VFS", "Mmap: Handle NULL destination hint"); + LEAVE('n'); + return NULL; + } } + tPage *mapping_dest = (void*)(mapping_base & ~(PAGE_SIZE-1)); // Handle anonymous mappings if( Flags & MMAP_MAP_ANONYMOUS ) @@ -67,14 +75,14 @@ void *VFS_MMap(void *DestHint, size_t Length, int Protection, int Flags, int FD, Mutex_Acquire( &h->Node->Lock ); + tVFS_MMapPageBlock *pb, **pb_pnp = (tVFS_MMapPageBlock**)&h->Node->MMapInfo; // 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 - ) - ; + for( pb = h->Node->MMapInfo; pb; pb_pnp = &pb->Next, pb = pb->Next ) + { + if( pb->BaseOffset + MMAP_PAGES_PER_BLOCK <= pagenum ) + break; + } LOG("pb = %p, pb->BaseOffset = %X", pb, pb ? pb->BaseOffset : 0); @@ -89,74 +97,22 @@ void *VFS_MMap(void *DestHint, size_t Length, int Protection, int Flags, int FD, } pb->Next = old_pb; pb->BaseOffset = pagenum - pagenum % MMAP_PAGES_PER_BLOCK; - if(prev) - prev->Next = pb; - else - h->Node->MMapInfo = pb; + *pb_pnp = pb; } // - Map (and allocate) pages while( npages -- ) { - assert( pagenum >= pb->BaseOffset ); - assert( pagenum - pb->BaseOffset < MMAP_PAGES_PER_BLOCK ); + ASSERTC( pagenum, >=, pb->BaseOffset ); + ASSERTC( pagenum - pb->BaseOffset, <, MMAP_PAGES_PER_BLOCK ); if( MM_GetPhysAddr( mapping_dest ) == 0 ) { - if( pb->PhysAddrs[pagenum - pb->BaseOffset] == 0 ) - { - tVFS_NodeType *nt = h->Node->Type; - if( !nt ) - { - // TODO: error - } - else if( nt->MMap ) - nt->MMap(h->Node, pagenum*PAGE_SIZE, PAGE_SIZE, mapping_dest); - else - { - int read_len; - // Allocate pages and read data - if( MM_Allocate(mapping_dest) == 0 ) { - // TODO: Unwrap - Mutex_Release( &h->Node->Lock ); - LEAVE('n'); - return NULL; - } - // TODO: Clip read length - read_len = nt->Read(h->Node, pagenum*PAGE_SIZE, PAGE_SIZE, - mapping_dest, 0); - // TODO: This was commented out, why? - if( read_len != PAGE_SIZE ) { - memset( (char*)mapping_dest + read_len, 0, PAGE_SIZE-read_len ); - } - } - pb->PhysAddrs[pagenum - pb->BaseOffset] = MM_GetPhysAddr( mapping_dest ); - MM_SetPageNode( pb->PhysAddrs[pagenum - pb->BaseOffset], h->Node ); - MM_RefPhys( pb->PhysAddrs[pagenum - pb->BaseOffset] ); - LOG("Read and map %X to %p (%P)", pagenum*PAGE_SIZE, mapping_dest, - pb->PhysAddrs[pagenum - pb->BaseOffset]); - } - else + LOG("Map page to %p", mapping_dest); + if( VFS_MMap_MapPage(h->Node, pagenum, pb, mapping_dest, Protection) ) { - MM_Map( mapping_dest, pb->PhysAddrs[pagenum - pb->BaseOffset] ); - MM_RefPhys( pb->PhysAddrs[pagenum - pb->BaseOffset] ); - LOG("Cached map %X to %p (%P)", pagenum*PAGE_SIZE, mapping_dest, - pb->PhysAddrs[pagenum - pb->BaseOffset]); - } - h->Node->ReferenceCount ++; - - // Set flags - if( !(Protection & MMAP_PROT_WRITE) ) { - MM_SetFlags(mapping_dest, MM_PFLAG_RO, MM_PFLAG_RO); - } - else { - MM_SetFlags(mapping_dest, 0, MM_PFLAG_RO); - } - - if( Protection & MMAP_PROT_EXEC ) { - MM_SetFlags(mapping_dest, MM_PFLAG_EXEC, MM_PFLAG_EXEC); - } - else { - MM_SetFlags(mapping_dest, 0, MM_PFLAG_EXEC); + Mutex_Release( &h->Node->Lock ); + LEAVE('n'); + return NULL; } } else @@ -167,25 +123,27 @@ void *VFS_MMap(void *DestHint, size_t Length, int Protection, int Flags, int FD, MM_SetFlags(mapping_dest, 0, MM_PFLAG_RO); } } - if( Flags & MMAP_MAP_PRIVATE ) + if( Flags & MMAP_MAP_PRIVATE ) { + // TODO: Don't allow the page to change underneath either MM_SetFlags(mapping_dest, MM_PFLAG_COW, MM_PFLAG_COW); + } pagenum ++; mapping_dest ++; // 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 + if( !pb->Next || pb->Next->BaseOffset != pagenum ) { - 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; + if( pb->Next ) ASSERTC(pb->Next->BaseOffset % MMAP_PAGES_PER_BLOCK, ==, 0); + tVFS_MMapPageBlock *newpb = malloc( sizeof(tVFS_MMapPageBlock) ); + newpb->Next = pb->Next; + newpb->BaseOffset = pagenum; + memset(newpb->PhysAddrs, 0, sizeof(newpb->PhysAddrs)); + pb->Next = newpb; } + + pb = pb->Next; } } @@ -263,6 +221,66 @@ void *VFS_MMap_Anon(void *Destination, size_t Length, Uint FlagsSet, Uint FlagsM return Destination; } +int VFS_MMap_MapPage(tVFS_Node *Node, unsigned int pagenum, tVFS_MMapPageBlock *pb, void *mapping_dest, unsigned int Protection) +{ + if( pb->PhysAddrs[pagenum - pb->BaseOffset] != 0 ) + { + MM_Map( mapping_dest, pb->PhysAddrs[pagenum - pb->BaseOffset] ); + MM_RefPhys( pb->PhysAddrs[pagenum - pb->BaseOffset] ); + LOG("Cached map %X to %p (%P)", pagenum*PAGE_SIZE, mapping_dest, + pb->PhysAddrs[pagenum - pb->BaseOffset]); + } + else + { + tVFS_NodeType *nt = Node->Type; + if( !nt ) + { + // TODO: error + } + else if( nt->MMap ) + nt->MMap(Node, pagenum*PAGE_SIZE, PAGE_SIZE, mapping_dest); + else + { + int read_len; + // Allocate pages and read data + if( MM_Allocate(mapping_dest) == 0 ) { + // TODO: Unwrap + return 1; + } + // TODO: Clip read length + read_len = nt->Read(Node, pagenum*PAGE_SIZE, PAGE_SIZE, mapping_dest, 0); + // TODO: This was commented out, why? + if( read_len != PAGE_SIZE ) { + memset( (char*)mapping_dest + read_len, 0, PAGE_SIZE-read_len ); + } + } + pb->PhysAddrs[pagenum - pb->BaseOffset] = MM_GetPhysAddr( mapping_dest ); + MM_SetPageNode( pb->PhysAddrs[pagenum - pb->BaseOffset], Node ); + MM_RefPhys( pb->PhysAddrs[pagenum - pb->BaseOffset] ); + LOG("Read and map %X to %p (%P)", pagenum*PAGE_SIZE, mapping_dest, + pb->PhysAddrs[pagenum - pb->BaseOffset]); + } + // TODO: Huh? + Node->ReferenceCount ++; + + // Set flags + if( !(Protection & MMAP_PROT_WRITE) ) { + MM_SetFlags(mapping_dest, MM_PFLAG_RO, MM_PFLAG_RO); + } + else { + MM_SetFlags(mapping_dest, 0, MM_PFLAG_RO); + } + + if( Protection & MMAP_PROT_EXEC ) { + MM_SetFlags(mapping_dest, MM_PFLAG_EXEC, MM_PFLAG_EXEC); + } + else { + MM_SetFlags(mapping_dest, 0, MM_PFLAG_EXEC); + } + + return 0; +} + int VFS_MUnmap(void *Addr, size_t Length) { return 0;