#include <mm_virt.h>
#include <hal_proc.h>
-#define AP_KRW_ONLY 0x1
-#define AP_KRO_ONLY 0x5
-#define AP_RW_BOTH 0x3
-#define AP_RO_BOTH 0x6
+#define AP_KRW_ONLY 1 // Kernel page
+#define AP_KRO_ONLY 5 // Kernel RO page
+#define AP_RW_BOTH 3 // Standard RW
+#define AP_RO_BOTH 6 // COW Page
+#define AP_RO_USER 2 // User RO Page
#define PADDR_MASK_LVL1 0xFFFFFC00
// === IMPORTS ===
int MM_int_AllocateCoarse(tVAddr VAddr, int Domain);
int MM_int_SetPageInfo(tVAddr VAddr, tMM_PageInfo *pi);
int MM_int_GetPageInfo(tVAddr VAddr, tMM_PageInfo *pi);
+tVAddr MM_NewUserStack(void);
+tPAddr MM_AllocateZero(tVAddr VAddr);
tPAddr MM_AllocateRootTable(void);
void MM_int_CloneTable(Uint32 *DestEnt, int Table);
tPAddr MM_Clone(void);
//void MM_DumpTables(tVAddr Start, tVAddr End);
// === GLOBALS ===
+tPAddr giMM_ZeroPage;
// === CODE ===
int MM_InitialiseVirtual(void)
switch(pi.AP)
{
+ case 0:
+ break;
case AP_KRW_ONLY:
ret |= MM_PFLAG_KERNEL;
break;
case AP_RW_BOTH:
break;
case AP_RO_BOTH:
+ ret |= MM_PFLAG_COW;
+ break;
+ case AP_RO_USER:
ret |= MM_PFLAG_RO;
break;
}
void MM_SetFlags(tVAddr VAddr, Uint Flags, Uint Mask)
{
tMM_PageInfo pi;
+ Uint curFlags;
+
if( MM_int_GetPageInfo(VAddr, &pi) )
- return;
+ return ;
+
+ curFlags = MM_GetPhysAddr(VAddr);
+ if( (curFlags & Mask) == Flags )
+ return ;
+ curFlags &= ~Mask;
+ curFlags |= Flags;
+
+ if( curFlags & MM_PFLAG_COW )
+ pi.AP = AP_RO_BOTH;
+ else
+ {
+ switch(curFlags & (MM_PFLAG_KERNEL|MM_PFLAG_RO) )
+ {
+ case 0:
+ pi.AP = AP_RW_BOTH; break;
+ case MM_PFLAG_KERNEL:
+ pi.AP = AP_KRW_ONLY; break;
+ case MM_PFLAG_RO:
+ pi.AP = AP_RO_USER; break;
+ case MM_PFLAG_KERNEL|MM_PFLAG_RO:
+ pi.AP = AP_KRO_ONLY; break;
+ }
+ }
+
+ pi.bExecutable = !!(curFlags & MM_PFLAG_EXEC);
+
+ MM_int_SetPageInfo(VAddr, &pi);
}
int MM_Map(tVAddr VAddr, tPAddr PAddr)
pi.PhysAddr = PAddr;
pi.Size = 12;
- pi.AP = AP_KRW_ONLY; // Kernel Read/Write
+ if(VAddr < USER_STACK_TOP)
+ pi.AP = AP_RW_BOTH;
+ else
+ pi.AP = AP_KRW_ONLY; // Kernel Read/Write
pi.bExecutable = 1;
if( MM_int_SetPageInfo(VAddr, &pi) ) {
MM_DerefPhys(pi.PhysAddr);
pi.PhysAddr = MM_AllocPhys();
if( pi.PhysAddr == 0 ) LEAVE_RET('i', 0);
pi.Size = 12;
- pi.AP = AP_KRW_ONLY; // Kernel Read/Write
+ if(VAddr < USER_STACK_TOP)
+ pi.AP = AP_RW_BOTH;
+ else
+ pi.AP = AP_KRW_ONLY;
pi.bExecutable = 1;
if( MM_int_SetPageInfo(VAddr, &pi) ) {
MM_DerefPhys(pi.PhysAddr);
return pi.PhysAddr;
}
+tPAddr MM_AllocateZero(tVAddr VAddr)
+{
+ if( !giMM_ZeroPage ) {
+ giMM_ZeroPage = MM_Allocate(VAddr);
+ MM_RefPhys(giMM_ZeroPage);
+ memset((void*)VAddr, 0, PAGE_SIZE);
+ }
+ else {
+ MM_RefPhys(giMM_ZeroPage);
+ MM_Map(VAddr, giMM_ZeroPage);
+ }
+ MM_SetFlags(VAddr, MM_PFLAG_COW, MM_PFLAG_COW);
+ return giMM_ZeroPage;
+}
+
void MM_Deallocate(tVAddr VAddr)
{
tMM_PageInfo pi;
return addr + ofs;
}
+tVAddr MM_NewUserStack(void)
+{
+ tVAddr addr, ofs;
+
+ addr = USER_STACK_TOP - USER_STACK_SIZE;
+ if( MM_GetPhysAddr(addr + PAGE_SIZE) ) {
+ Log_Error("MMVirt", "Unable to create initial user stack, addr %p taken",
+ addr + PAGE_SIZE
+ );
+ return 0;
+ }
+
+ // 1 guard page
+ for( ofs = PAGE_SIZE; ofs < USER_STACK_SIZE; ofs += PAGE_SIZE )
+ {
+ tPAddr rv;
+ if(ofs >= USER_STACK_SIZE - USER_STACK_COMM)
+ rv = MM_Allocate(addr + ofs);
+ else
+ rv = MM_AllocateZero(addr + ofs);
+ if(rv == 0)
+ {
+ while(ofs)
+ {
+ ofs -= PAGE_SIZE;
+ MM_Deallocate(addr + ofs);
+ }
+ Log_Warning("MMVirt", "MM_NewUserStack: Unable to allocate");
+ return 0;
+ }
+ MM_SetFlags(addr+ofs, 0, MM_PFLAG_KERNEL);
+ }
+ Log("Return %p", addr + ofs);
+ MM_DumpTables(0, 0x80000000);
+ return addr + ofs;
+}
+
void MM_int_DumpTableEnt(tVAddr Start, size_t Len, tMM_PageInfo *Info)
{
- Log("%p => %8x - 0x%7x %i %x",
- Start, Info->PhysAddr-Len, Len,
- Info->Domain,
- Info->AP
- );
+ if( giMM_ZeroPage && Info->PhysAddr == giMM_ZeroPage )
+ {
+ Log("%p => %8s - 0x%7x %i %x",
+ Start, "ZERO", Len,
+ Info->Domain, Info->AP
+ );
+ }
+ else
+ {
+ Log("%p => %8x - 0x%7x %i %x",
+ Start, Info->PhysAddr-Len, Len,
+ Info->Domain, Info->AP
+ );
+ }
}
void MM_DumpTables(tVAddr Start, tVAddr End)
}
pi_old = pi;
- pi_old.PhysAddr += 1 << pi_old.Size;
+ // Handle the zero page
+ if( !giMM_ZeroPage || pi_old.Size != 12 || pi_old.PhysAddr != giMM_ZeroPage )
+ pi_old.PhysAddr += 1 << pi_old.Size;
addr += 1 << pi_old.Size;
inRange = (rv == 0);
}