#include <arch_int.h>
#include <semaphore.h>
+#define TRACE_MAPS 0
+
#define TAB 22
#define WORKER_STACKS 0x00100000 // Thread0 Only!
typedef Uint32 tTabEnt;
// === IMPORTS ===
-extern char _UsertextEnd[], _UsertextBase[];
+extern tPage _UsertextEnd;
+extern tPage _UsertextBase;
extern Uint32 gaInitPageDir[1024];
extern Uint32 gaInitPageTable[1024];
extern void Threads_SegFault(tVAddr Addr);
-extern void Error_Backtrace(Uint eip, Uint ebp);
// === PROTOTYPES ===
void MM_PreinitVirtual(void);
int Length;
int Flags;
} *gaMappedRegions; // sizeof = 24 bytes
+// - Zero page
+tShortSpinlock glMM_ZeroPage;
+tPAddr giMM_ZeroPage;
// === CODE ===
/**
}
// Unset kernel on the User Text pages
- for( int i = ((tVAddr)&_UsertextEnd-(tVAddr)&_UsertextBase+0xFFF)/4096; i--; ) {
- MM_SetFlags( (tVAddr)&_UsertextBase + i*4096, 0, MM_PFLAG_KERNEL );
+ ASSERT( ((tVAddr)&_UsertextBase & (PAGE_SIZE-1)) == 0 );
+ //ASSERT( ((tVAddr)&_UsertextEnd & (PAGE_SIZE-1)) == 0 );
+ for( tPage *page = &_UsertextBase; page < &_UsertextEnd; page ++ )
+ {
+ MM_SetFlags( page, 0, MM_PFLAG_KERNEL );
}
*gpTmpCR3 = 0;
/**
* \fn tPAddr MM_Allocate(tVAddr VAddr)
*/
-tPAddr MM_Allocate(tVAddr VAddr)
+tPAddr MM_Allocate(volatile void * VAddr)
{
- tPAddr paddr;
- //ENTER("xVAddr", VAddr);
- //__ASM__("xchg %bx,%bx");
- // Check if the directory is mapped
- if( gaPageDir[ VAddr >> 22 ] == 0 )
- {
- // Allocate directory
- paddr = MM_AllocPhys();
- if( paddr == 0 ) {
- Warning("MM_Allocate - Out of Memory (Called by %p)", __builtin_return_address(0));
- //LEAVE('i',0);
- return 0;
- }
- // Map and mark as user (if needed)
- gaPageDir[ VAddr >> 22 ] = paddr | 3;
- if(VAddr < MM_USER_MAX) gaPageDir[ VAddr >> 22 ] |= PF_USER;
-
- INVLPG( &gaPageDir[ VAddr >> 22 ] );
- memsetd( &gaPageTable[ (VAddr >> 12) & ~0x3FF ], 0, 1024 );
+ tPAddr paddr = MM_AllocPhys();
+ if( MM_Map(VAddr, paddr) ) {
+ return paddr;
}
- // Check if the page is already allocated
- else if( gaPageTable[ VAddr >> 12 ] != 0 ) {
+
+ // Error of some form, either an overwrite or OOM
+ MM_DerefPhys(paddr);
+
+ // Check for overwrite
+ paddr = MM_GetPhysAddr(VAddr);
+ if( paddr != 0 ) {
Warning("MM_Allocate - Allocating to used address (%p)", VAddr);
- //LEAVE('X', gaPageTable[ VAddr >> 12 ] & ~0xFFF);
- return gaPageTable[ VAddr >> 12 ] & ~0xFFF;
+ return paddr;
}
- // Allocate
- paddr = MM_AllocPhys();
- //LOG("paddr = 0x%llx", paddr);
- if( paddr == 0 ) {
- Warning("MM_Allocate - Out of Memory when allocating at %p (Called by %p)",
- VAddr, __builtin_return_address(0));
- //LEAVE('i',0);
- return 0;
- }
- // Map
- gaPageTable[ VAddr >> 12 ] = paddr | 3;
- // Mark as user
- if(VAddr < MM_USER_MAX) gaPageTable[ VAddr >> 12 ] |= PF_USER;
- // Invalidate Cache for address
- INVLPG( VAddr & ~0xFFF );
-
- //LEAVE('X', paddr);
- return paddr;
+ // OOM
+ Warning("MM_Allocate - Out of Memory (Called by %p)", __builtin_return_address(0));
+ return 0;
}
-/**
- * \fn void MM_Deallocate(tVAddr VAddr)
- */
-void MM_Deallocate(tVAddr VAddr)
+void MM_AllocateZero(volatile void *VAddr)
{
- if( gaPageDir[ VAddr >> 22 ] == 0 ) {
- Warning("MM_Deallocate - Directory not mapped");
- return;
+ if( MM_GetPhysAddr(VAddr) ) {
+ Warning("MM_AllocateZero - Attempted overwrite at %p", VAddr);
+ return ;
}
-
- if(gaPageTable[ VAddr >> 12 ] == 0) {
- Warning("MM_Deallocate - Page is not allocated");
- return;
+ if( !giMM_ZeroPage )
+ {
+ SHORTLOCK(&glMM_ZeroPage);
+ // Check again within the lock (just in case we lost the race)
+ if( giMM_ZeroPage == 0 )
+ {
+ giMM_ZeroPage = MM_Allocate(VAddr);
+ // - Reference a second time to prevent it from being freed
+ MM_RefPhys(giMM_ZeroPage);
+ memset((void*)VAddr, 0, PAGE_SIZE);
+ }
+ SHORTREL(&glMM_ZeroPage);
}
-
- // Dereference page
- MM_DerefPhys( gaPageTable[ VAddr >> 12 ] & ~0xFFF );
- // Clear page
- gaPageTable[ VAddr >> 12 ] = 0;
-}
-
-/**
- * \fn tPAddr MM_GetPhysAddr(tVAddr Addr)
- * \brief Checks if the passed address is accesable
- */
-tPAddr MM_GetPhysAddr(volatile const void *Addr)
-{
- tVAddr addr = (tVAddr)Addr;
- if( !(gaPageDir[addr >> 22] & 1) )
- return 0;
- if( !(gaPageTable[addr >> 12] & 1) )
- return 0;
- return (gaPageTable[addr >> 12] & ~0xFFF) | (addr & 0xFFF);
-}
-
-/**
- * \fn void MM_SetCR3(Uint CR3)
- * \brief Sets the current process space
- */
-void MM_SetCR3(Uint CR3)
-{
- __ASM__("mov %0, %%cr3"::"r"(CR3));
+ else
+ {
+ MM_Map(VAddr, giMM_ZeroPage);
+ }
+ MM_SetFlags(VAddr, MM_PFLAG_COW, MM_PFLAG_COW);
}
/**
* \fn int MM_Map(tVAddr VAddr, tPAddr PAddr)
* \brief Map a physical page to a virtual one
*/
-int MM_Map(tVAddr VAddr, tPAddr PAddr)
+int MM_Map(volatile void *VAddr, tPAddr PAddr)
{
- //ENTER("xVAddr xPAddr", VAddr, PAddr);
+ Uint pagenum = (tVAddr)VAddr >> 12;
+
+ #if TRACE_MAPS
+ Debug("MM_Map(%p, %P)", VAddr, PAddr);
+ #endif
+
// Sanity check
- if( PAddr & 0xFFF || VAddr & 0xFFF ) {
+ if( PAddr & 0xFFF || (tVAddr)VAddr & 0xFFF ) {
Log_Warning("MM_Virt", "MM_Map - Physical or Virtual Addresses are not aligned (0x%P and %p)",
PAddr, VAddr);
//LEAVE('i', 0);
return 0;
}
- // Align addresses
- PAddr &= ~0xFFF; VAddr &= ~0xFFF;
-
+ bool is_user = ((tVAddr)VAddr < MM_USER_MAX);
+
// Check if the directory is mapped
- if( gaPageDir[ VAddr >> 22 ] == 0 )
+ if( gaPageDir[ pagenum >> 10 ] == 0 )
{
tPAddr tmp = MM_AllocPhys();
if( tmp == 0 )
return 0;
- gaPageDir[ VAddr >> 22 ] = tmp | 3;
+ gaPageDir[ pagenum >> 10 ] = tmp | 3 | (is_user ? PF_USER : 0);
- // Mark as user
- if(VAddr < MM_USER_MAX) gaPageDir[ VAddr >> 22 ] |= PF_USER;
-
- INVLPG( &gaPageTable[ (VAddr >> 12) & ~0x3FF ] );
- memsetd( &gaPageTable[ (VAddr >> 12) & ~0x3FF ], 0, 1024 );
+ INVLPG( &gaPageTable[ pagenum & ~0x3FF ] );
+ memsetd( &gaPageTable[ pagenum & ~0x3FF ], 0, 1024 );
}
// Check if the page is already allocated
- else if( gaPageTable[ VAddr >> 12 ] != 0 ) {
+ else if( gaPageTable[ pagenum ] != 0 ) {
Warning("MM_Map - Allocating to used address");
//LEAVE('i', 0);
return 0;
}
// Map
- gaPageTable[ VAddr >> 12 ] = PAddr | 3;
- // Mark as user
- if(VAddr < MM_USER_MAX) gaPageTable[ VAddr >> 12 ] |= PF_USER;
-
- //LOG("gaPageTable[ 0x%x ] = (Uint)%p = 0x%x",
- // VAddr >> 12, &gaPageTable[ VAddr >> 12 ], gaPageTable[ VAddr >> 12 ]);
+ gaPageTable[ pagenum ] = PAddr | 3 | (is_user ? PF_USER : 0);
// Reference
MM_RefPhys( PAddr );
- //LOG("INVLPG( 0x%x )", VAddr);
INVLPG( VAddr );
- //LEAVE('i', 1);
return 1;
}
+/*
+ * A.k.a MM_Unmap
+ */
+void MM_Deallocate(volatile void *VAddr)
+{
+ Uint pagenum = (tVAddr)VAddr >> 12;
+ if( gaPageDir[pagenum>>10] == 0 ) {
+ Warning("MM_Deallocate - Directory not mapped");
+ return;
+ }
+
+ if(gaPageTable[pagenum] == 0) {
+ Warning("MM_Deallocate - Page is not allocated");
+ return;
+ }
+
+ // Dereference and clear page
+ tPAddr paddr = gaPageTable[pagenum] & ~0xFFF;
+ gaPageTable[pagenum] = 0;
+ MM_DerefPhys( paddr );
+}
+
+/**
+ * \fn tPAddr MM_GetPhysAddr(tVAddr Addr)
+ * \brief Checks if the passed address is accesable
+ */
+tPAddr MM_GetPhysAddr(volatile const void *Addr)
+{
+ tVAddr addr = (tVAddr)Addr;
+ if( !(gaPageDir[addr >> 22] & 1) )
+ return 0;
+ if( !(gaPageTable[addr >> 12] & 1) )
+ return 0;
+ return (gaPageTable[addr >> 12] & ~0xFFF) | (addr & 0xFFF);
+}
+
+/**
+ * \fn void MM_SetCR3(Uint CR3)
+ * \brief Sets the current process space
+ */
+void MM_SetCR3(Uint CR3)
+{
+ __ASM__("mov %0, %%cr3"::"r"(CR3));
+}
+
/**
* \brief Clear user's address space
*/
*/
tVAddr MM_NewKStack(void)
{
- tVAddr base;
- Uint i;
- for(base = MM_KERNEL_STACKS; base < MM_KERNEL_STACKS_END; base += MM_KERNEL_STACK_SIZE)
+ for(tVAddr base = MM_KERNEL_STACKS; base < MM_KERNEL_STACKS_END; base += MM_KERNEL_STACK_SIZE)
{
+ tPage *pageptr = (void*)base;
// Check if space is free
- if(MM_GetPhysAddr( (void*) base) != 0)
+ if(MM_GetPhysAddr(pageptr) != 0)
continue;
// Allocate
- //for(i = MM_KERNEL_STACK_SIZE; i -= 0x1000 ; )
- for(i = 0; i < MM_KERNEL_STACK_SIZE; i += 0x1000 )
+ for(Uint i = 0; i < MM_KERNEL_STACK_SIZE/PAGE_SIZE; i ++ )
{
- if( MM_Allocate(base+i) == 0 )
+ if( MM_Allocate(pageptr + i) == 0 )
{
// On error, print a warning and return error
Warning("MM_NewKStack - Out of memory");
* \fn void MM_SetFlags(tVAddr VAddr, Uint Flags, Uint Mask)
* \brief Sets the flags on a page
*/
-void MM_SetFlags(tVAddr VAddr, Uint Flags, Uint Mask)
+void MM_SetFlags(volatile void *VAddr, Uint Flags, Uint Mask)
{
- tTabEnt *ent;
- if( !(gaPageDir[VAddr >> 22] & 1) ) return ;
- if( !(gaPageTable[VAddr >> 12] & 1) ) return ;
+ Uint pagenum = (tVAddr)VAddr >> 12;
+ if( !(gaPageDir[pagenum >> 10] & 1) ) return ;
+ if( !(gaPageTable[pagenum] & 1) ) return ;
- ent = &gaPageTable[VAddr >> 12];
+ tTabEnt *ent = &gaPageTable[pagenum];
// Read-Only
if( Mask & MM_PFLAG_RO )
*ent &= ~PF_WRITE;
}
else {
- gaPageDir[VAddr >> 22] |= PF_WRITE;
+ gaPageDir[pagenum >> 10] |= PF_WRITE;
*ent |= PF_WRITE;
}
}
*ent &= ~PF_USER;
}
else {
- gaPageDir[VAddr >> 22] |= PF_USER;
+ gaPageDir[pagenum >> 10] |= PF_USER;
*ent |= PF_USER;
}
}
/**
* \brief Get the flags on a page
*/
-Uint MM_GetFlags(tVAddr VAddr)
+Uint MM_GetFlags(volatile const void *VAddr)
{
- tTabEnt *ent;
- Uint ret = 0;
+ Uint pagenum = (tVAddr)VAddr >> 12;
// Validity Check
- if( !(gaPageDir[VAddr >> 22] & 1) ) return 0;
- if( !(gaPageTable[VAddr >> 12] & 1) ) return 0;
+ if( !(gaPageDir[pagenum >> 10] & 1) ) return 0;
+ if( !(gaPageTable[pagenum] & 1) ) return 0;
- ent = &gaPageTable[VAddr >> 12];
+ tTabEnt *ent = &gaPageTable[pagenum];
+ Uint ret = 0;
// Read-Only
if( !(*ent & PF_WRITE) ) ret |= MM_PFLAG_RO;
// Kernel
* \fn void MM_UnmapHWPages(tVAddr VAddr, Uint Number)
* \brief Unmap a hardware page
*/
-void MM_UnmapHWPages(tVAddr VAddr, Uint Number)
+void MM_UnmapHWPages(volatile void *Base, Uint Number)
{
- int i, j;
-
+ tVAddr VAddr = (tVAddr)Base;
//Log_Debug("VirtMem", "MM_UnmapHWPages: (VAddr=0x%08x, Number=%i)", VAddr, Number);
//
if( KERNEL_BASE <= VAddr && VAddr < KERNEL_BASE + 1024*1024 )
- return ;
+ return ;
+
+ Uint pagenum = VAddr >> 12;
// Sanity Check
if(VAddr < HW_MAP_ADDR || VAddr+Number*0x1000 > HW_MAP_MAX) return;
- i = VAddr >> 12;
Mutex_Acquire( &glTempMappings ); // Temp and HW share a directory, so they share a lock
- for( j = 0; j < Number; j++ )
+ for( Uint i = 0; i < Number; i ++ )
{
- MM_DerefPhys( gaPageTable[ i + j ] & ~0xFFF );
- gaPageTable[ i + j ] = 0;
- INVLPG( (tVAddr)(i+j) << 12 );
+ MM_DerefPhys( gaPageTable[ pagenum + i ] & ~0xFFF );
+ gaPageTable[ pagenum + i ] = 0;
+ INVLPG( (tVAddr)(pagenum + i) << 12 );
}
Mutex_Release( &glTempMappings );
git.ucc.asn.au / tpg / acess2.git / blobdiff
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