* 0xFE - Unused
* 0xFF - System Calls / Kernel's User Code
*/
+#define DEBUG 1
#include <common.h>
#include <mm_phys.h>
#include <proc.h>
-#define KERNEL_STACKS 0xF0000000
+#define KERNEL_STACKS 0xF0000000
#define KERNEL_STACK_SIZE 0x00002000
-#define KERNEL_STACK_END 0xFD000000
+#define KERNEL_STACKS_END 0xFD000000
+#define WORKER_STACKS 0x00100000 // Thread0 Only!
+#define WORKER_STACK_SIZE KERNEL_STACK_SIZE
+#define WORKER_STACKS_END 0xB0000000
+#define NUM_WORKER_STACKS ((WORKER_STACKS_END-WORKER_STACKS)/WORKER_STACK_SIZE)
#define PAGE_TABLE_ADDR 0xFD000000
#define PAGE_DIR_ADDR 0xFD3F4000
#define PAGE_CR3_ADDR 0xFD3F4FD0
#define TEMP_MAP_ADDR 0xFEFF0000 // Allows 16 "temp" pages
#define NUM_TEMP_PAGES 16
-#define USE_COW 1
-
#define PF_PRESENT 0x1
#define PF_WRITE 0x2
#define PF_USER 0x4
// === IMPORTS ===
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 MM_InstallVirtual();
-void MM_PageFault(Uint Addr, Uint ErrorCode, tRegs *Regs);
+void MM_PageFault(tVAddr Addr, Uint ErrorCode, tRegs *Regs);
void MM_DumpTables(tVAddr Start, tVAddr End);
-tPAddr MM_DuplicatePage(Uint VAddr);
+tPAddr MM_DuplicatePage(tVAddr VAddr);
// === GLOBALS ===
tPAddr *gaPageTable = (void*)PAGE_TABLE_ADDR;
tPAddr *gaTmpDir = (void*)TMP_DIR_ADDR;
tPAddr *gTmpCR3 = (void*)TMP_CR3_ADDR;
int gilTempMappings = 0;
+ int gilTempFractal = 0;
+Uint32 gWorkerStacks[(NUM_WORKER_STACKS+31)/32];
+ int giLastUsedWorker = 0;
// === CODE ===
/**
{
if( gaPageDir[ i ] ) continue;
// Skip stack tables, they are process unique
- if( i > KERNEL_STACKS >> 22 && i < KERNEL_STACK_END >> 22) {
+ if( i > KERNEL_STACKS >> 22 && i < KERNEL_STACKS_END >> 22) {
gaPageDir[ i ] = 0;
continue;
}
}
/**
- * \fn void MM_PageFault(Uint Addr, Uint ErrorCode, tRegs *Regs)
+ * \fn void MM_PageFault(tVAddr Addr, Uint ErrorCode, tRegs *Regs)
* \brief Called on a page fault
*/
-void MM_PageFault(Uint Addr, Uint ErrorCode, tRegs *Regs)
+void MM_PageFault(tVAddr Addr, Uint ErrorCode, tRegs *Regs)
{
- ENTER("xAddr bErrorCode", Addr, ErrorCode);
+ //ENTER("xAddr bErrorCode", Addr, ErrorCode);
// -- Check for COW --
if( gaPageDir [Addr>>22] & PF_PRESENT
&& gaPageTable[Addr>>12] & PF_COW )
{
tPAddr paddr;
- paddr = MM_DuplicatePage( Addr );
- MM_DerefPhys( gaPageTable[Addr>>12] & ~0xFFF );
- gaPageTable[Addr>>12] &= PF_USER;
- gaPageTable[Addr>>12] |= paddr|PF_PRESENT|PF_WRITE;
+ if(MM_GetRefCount( gaPageTable[Addr>>12] & ~0xFFF ) == 1)
+ {
+ gaPageTable[Addr>>12] &= ~PF_COW;
+ gaPageTable[Addr>>12] |= PF_PRESENT|PF_WRITE;
+ }
+ else
+ {
+ paddr = MM_DuplicatePage( Addr );
+ MM_DerefPhys( gaPageTable[Addr>>12] & ~0xFFF );
+ gaPageTable[Addr>>12] &= PF_USER;
+ gaPageTable[Addr>>12] |= paddr|PF_PRESENT|PF_WRITE;
+ }
+
INVLPG( Addr & ~0xFFF );
- LEAVE('-');
+ //LEAVE('-')
return;
}
+ // If it was a user, tell the thread handler
+ if(ErrorCode & 4) {
+ Warning("%s %s %s memory%s",
+ (ErrorCode&4?"User":"Kernel"),
+ (ErrorCode&2?"write to":"read from"),
+ (ErrorCode&1?"bad/locked":"non-present"),
+ (ErrorCode&16?" (Instruction Fetch)":"")
+ );
+ Warning("User Pagefault: Instruction at %p accessed %p", Regs->eip, Addr);
+ __asm__ __volatile__ ("sti"); // Restart IRQs
+ Threads_SegFault(Addr);
+ return ;
+ }
+
// -- Check Error Code --
if(ErrorCode & 8)
Warning("Reserved Bits Trashed!");
);
}
+ Log("Code at %p accessed %p", Regs->eip, Addr);
+ // Print Stack Backtrace
+ Error_Backtrace(Regs->eip, Regs->ebp);
+
Log("gaPageDir[0x%x] = 0x%x", Addr>>22, gaPageDir[Addr>>22]);
if( gaPageDir[Addr>>22] & PF_PRESENT )
Log("gaPageTable[0x%x] = 0x%x", Addr>>12, gaPageTable[Addr>>12]);
MM_DumpTables(0, -1);
Panic("Page Fault at 0x%x\n", Regs->eip);
- LEAVE('-');
}
/**
- * \fn void MM_DumpTables(Uint Start, Uint End)
+ * \fn void MM_DumpTables(tVAddr Start, tVAddr End)
* \brief Dumps the layout of the page tables
*/
void MM_DumpTables(tVAddr Start, tVAddr End)
const tPAddr MASK = ~0xF98;
Start >>= 12; End >>= 12;
+
+ #if 0
+ Log("Directory Entries:");
+ for(page = Start >> 10;
+ page < (End >> 10)+1;
+ page ++)
+ {
+ if(gaPageDir[page])
+ {
+ Log(" 0x%08x-0x%08x :: 0x%08x",
+ page<<22, ((page+1)<<22)-1,
+ gaPageDir[page]&~0xFFF
+ );
+ }
+ }
+ #endif
+
+ Log("Table Entries:");
for(page = Start, curPos = Start<<12;
page < End;
curPos += 0x1000, page++)
|| (gaPageTable[page] & MASK) != expected)
{
if(expected) {
- Log("0x%08x-0x%08x => 0x%08x-0x%08x (%s%s%s%s)",
+ Log(" 0x%08x-0x%08x => 0x%08x-0x%08x (%s%s%s%s)",
rangeStart, curPos - 1,
gaPageTable[rangeStart>>12] & ~0xFFF,
(expected & ~0xFFF) - 1,
}
/**
- * \fn tPAddr MM_Allocate(Uint VAddr)
+ * \fn tPAddr MM_Allocate(tVAddr VAddr)
*/
-tPAddr MM_Allocate(Uint VAddr)
+tPAddr MM_Allocate(tVAddr VAddr)
{
+ tPAddr paddr;
// Check if the directory is mapped
if( gaPageDir[ VAddr >> 22 ] == 0 )
{
// Allocate directory
- gaPageDir[ VAddr >> 22 ] = MM_AllocPhys() | 3;
+ paddr = MM_AllocPhys();
+ if( paddr == 0 ) {
+ Warning("MM_Allocate - Out of Memory (Called by %p)", __builtin_return_address(0));
+ return 0;
+ }
+ // Map
+ gaPageDir[ VAddr >> 22 ] = paddr | 3;
// Mark as user
if(VAddr < MM_USER_MAX) gaPageDir[ VAddr >> 22 ] |= PF_USER;
}
// Check if the page is already allocated
else if( gaPageTable[ VAddr >> 12 ] != 0 ) {
- Warning("MM_Allocate - Allocating to used address");
+ Warning("MM_Allocate - Allocating to used address (%p)", VAddr);
return gaPageTable[ VAddr >> 12 ] & ~0xFFF;
}
// Allocate
- gaPageTable[ VAddr >> 12 ] = MM_AllocPhys() | 3;
+ paddr = MM_AllocPhys();
+ if( paddr == 0 ) {
+ Warning("MM_Allocate - Out of Memory when allocating at %p (Called by %p)",
+ VAddr, __builtin_return_address(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 );
- return gaPageTable[ VAddr >> 12 ] & ~0xFFF;
+ return paddr;
}
/**
- * \fn void MM_Deallocate(Uint VAddr)
+ * \fn void MM_Deallocate(tVAddr VAddr)
*/
-void MM_Deallocate(Uint VAddr)
+void MM_Deallocate(tVAddr VAddr)
{
if( gaPageDir[ VAddr >> 22 ] == 0 ) {
Warning("MM_Deallocate - Directory not mapped");
}
/**
- * \fn tPAddr MM_GetPhysAddr(Uint Addr)
+ * \fn tPAddr MM_GetPhysAddr(tVAddr Addr)
* \brief Checks if the passed address is accesable
*/
-tPAddr MM_GetPhysAddr(Uint Addr)
+tPAddr MM_GetPhysAddr(tVAddr Addr)
{
if( !(gaPageDir[Addr >> 22] & 1) )
return 0;
return (gaPageTable[Addr >> 12] & ~0xFFF) | (Addr & 0xFFF);
}
+
/**
- * \fn void MM_SetCR3(Uint CR3)
+ * \fn int MM_IsUser(tVAddr Addr)
+ * \brief Checks if a page is user accessable
+ */
+int MM_IsUser(tVAddr Addr)
+{
+ if( !(gaPageDir[Addr >> 22] & 1) )
+ return 0;
+ if( !(gaPageTable[Addr >> 12] & 1) )
+ return 0;
+ if( !(gaPageTable[Addr >> 12] & PF_USER) )
+ return 0;
+ return 1;
+}
+
+/**
+ * \fn void MM_SetCR3(tPAddr CR3)
* \brief Sets the current process space
*/
-void MM_SetCR3(Uint CR3)
+void MM_SetCR3(tPAddr CR3)
{
__asm__ __volatile__ ("mov %0, %%cr3"::"r"(CR3));
}
/**
- * \fn int MM_Map(Uint VAddr, tPAddr PAddr)
+ * \fn int MM_Map(tVAddr VAddr, tPAddr PAddr)
* \brief Map a physical page to a virtual one
*/
-int MM_Map(Uint VAddr, tPAddr PAddr)
+int MM_Map(tVAddr VAddr, tPAddr PAddr)
{
//ENTER("xVAddr xPAddr", VAddr, PAddr);
// Sanity check
}
/**
- * \fn Uint MM_ClearUser()
+ * \fn tVAddr MM_ClearUser()
* \brief Clear user's address space
*/
-Uint MM_ClearUser()
+tVAddr MM_ClearUser()
{
Uint i, j;
}
MM_DerefPhys( gaPageDir[i] & ~0xFFF );
+ gaPageDir[i] = 0;
+ INVLPG( &gaPageTable[i*1024] );
}
+ INVLPG( gaPageDir );
-
- return *gTmpCR3;
+ return *gaPageCR3;
}
/**
- * \fn Uint MM_Clone()
+ * \fn tPAddr MM_Clone()
* \brief Clone the current address space
*/
-Uint MM_Clone()
+tPAddr MM_Clone()
{
Uint i, j;
- Uint kStackBase = gCurrentThread->KernelStack - KERNEL_STACK_SIZE;
+ tVAddr ret;
+ Uint page = 0;
+ tVAddr kStackBase = Proc_GetCurThread()->KernelStack - KERNEL_STACK_SIZE;
void *tmp;
- //ENTER("");
+ LOCK( &gilTempFractal );
// Create Directory Table
*gTmpCR3 = MM_AllocPhys() | 3;
// Check if table is allocated
if( !(gaPageDir[i] & PF_PRESENT) ) {
gaTmpDir[i] = 0;
+ page += 1024;
continue;
}
// Allocate new table
gaTmpDir[i] = MM_AllocPhys() | (gaPageDir[i] & 7);
- INVLPG( &gaTmpTable[i*1024] );
+ INVLPG( &gaTmpTable[page] );
// Fill
- for( j = 0; j < 1024; j ++ )
+ for( j = 0; j < 1024; j ++, page++ )
{
- if( !(gaPageTable[i*1024+j] & PF_PRESENT) ) {
- gaTmpTable[i*1024+j] = 0;
+ if( !(gaPageTable[page] & PF_PRESENT) ) {
+ gaTmpTable[page] = 0;
continue;
}
- #if USE_COW
// Refrence old page
- MM_RefPhys( gaPageTable[i*1024+j] & ~0xFFF );
+ MM_RefPhys( gaPageTable[page] & ~0xFFF );
// Add to new table
- if(gaPageTable[i*1024+j] & PF_WRITE) {
- gaTmpTable[i*1024+j] = (gaPageTable[i*1024+j] & ~PF_WRITE) | PF_COW;
- gaPageTable[i*1024+j] = (gaPageTable[i*1024+j] & ~PF_WRITE) | PF_COW;
+ if(gaPageTable[page] & PF_WRITE) {
+ gaTmpTable[page] = (gaPageTable[page] & ~PF_WRITE) | PF_COW;
+ gaPageTable[page] = (gaPageTable[page] & ~PF_WRITE) | PF_COW;
+ INVLPG( page << 12 );
}
else
- gaTmpTable[i*1024+j] = gaPageTable[i*1024+j];
- LOG("gaTmpTable[0x%x] = 0x%x", i*1024+j, gaTmpTable[i*1024+j]);
- #else
- gaTmpTable[i*1024+j] = MM_DuplicatePage( (i*1024+j)<<12 ) | (gaPageTable[i*1024+j]&7);
- #endif
+ gaTmpTable[page] = gaPageTable[page];
}
}
// Allocate kernel stack
for(i = KERNEL_STACKS >> 22;
- i < KERNEL_STACK_END >> 22;
+ i < KERNEL_STACKS_END >> 22;
i ++ )
{
// Check if directory is allocated
}
}
- //LEAVE('x', *gTmpCR3 & ~0xFFF);
- return *gTmpCR3 & ~0xFFF;
+ ret = *gTmpCR3 & ~0xFFF;
+ RELEASE( &gilTempFractal );
+
+ //LEAVE('x', ret);
+ return ret;
}
/**
- * \fn Uint MM_NewKStack()
+ * \fn tVAddr MM_NewKStack()
* \brief Create a new kernel stack
*/
-Uint MM_NewKStack()
+tVAddr MM_NewKStack()
{
- Uint base = KERNEL_STACKS;
+ tVAddr base = KERNEL_STACKS;
Uint i;
- for(;base<KERNEL_STACK_END;base+=KERNEL_STACK_SIZE)
+ for(;base<KERNEL_STACKS_END;base+=KERNEL_STACK_SIZE)
{
if(MM_GetPhysAddr(base) != 0) continue;
for(i=0;i<KERNEL_STACK_SIZE;i+=0x1000) {
}
/**
- * \fn void MM_SetFlags(Uint VAddr, Uint Flags, Uint Mask)
+ * \fn tVAddr MM_NewWorkerStack()
+ * \brief Creates a new worker stack
+ */
+tVAddr MM_NewWorkerStack()
+{
+ Uint esp, ebp;
+ Uint oldstack;
+ Uint base, addr;
+ int i, j;
+ Uint *tmpPage;
+ tPAddr pages[WORKER_STACK_SIZE>>12];
+
+ // Get the old ESP and EBP
+ __asm__ __volatile__ ("mov %%esp, %0": "=r"(esp));
+ __asm__ __volatile__ ("mov %%ebp, %0": "=r"(ebp));
+
+ // Find a free worker stack address
+ for(base = giLastUsedWorker; base < NUM_WORKER_STACKS; base++)
+ {
+ // Used block
+ if( gWorkerStacks[base/32] == -1 ) {
+ base += 31; base &= ~31;
+ base --; // Counteracted by the base++
+ continue;
+ }
+ // Used stack
+ if( gWorkerStacks[base/32] & (1 << base) ) {
+ continue;
+ }
+ break;
+ }
+ if(base >= NUM_WORKER_STACKS) {
+ Warning("Uh-oh! Out of worker stacks");
+ return 0;
+ }
+
+ // It's ours now!
+ gWorkerStacks[base/32] |= (1 << base);
+ // Make life easier for later calls
+ giLastUsedWorker = base;
+ // We have one
+ base = WORKER_STACKS + base * WORKER_STACK_SIZE;
+
+ // Acquire the lock for the temp fractal mappings
+ LOCK(&gilTempFractal);
+
+ // Set the temp fractals to TID0's address space
+ *gTmpCR3 = (Uint)gaInitPageDir | 3;
+ INVLPG( gaTmpDir );
+
+ // Check if the directory is mapped (we are assuming that the stacks
+ // will fit neatly in a directory
+ if(gaTmpDir[ base >> 22 ] == 0) {
+ gaTmpDir[ base >> 22 ] = MM_AllocPhys() | 3;
+ INVLPG( &gaTmpTable[ (base>>22) & ~0x3FF ] );
+ }
+
+ // Mapping Time!
+ for( addr = 0; addr < WORKER_STACK_SIZE; addr += 0x1000 )
+ {
+ pages[ addr >> 12 ] = MM_AllocPhys();
+ gaTmpTable[ (base + addr) >> 12 ] = pages[addr>>12] | 3;
+ }
+ // Release the temp mapping lock
+ RELEASE(&gilTempFractal);
+
+ // Copy the old stack
+ oldstack = (esp + KERNEL_STACK_SIZE-1) & ~(KERNEL_STACK_SIZE-1);
+ esp = oldstack - esp; // ESP as an offset in the stack
+
+ i = (WORKER_STACK_SIZE>>12) - 1;
+ // Copy the contents of the old stack to the new one, altering the addresses
+ // `addr` is refering to bytes from the stack base (mem downwards)
+ for(addr = 0; addr < esp; addr += 0x1000)
+ {
+ Uint *stack = (Uint*)( oldstack-(addr+0x1000) );
+ tmpPage = (void*)MM_MapTemp( pages[i] );
+ // Copy old stack
+ for(j = 0; j < 1024; j++)
+ {
+ // Possible Stack address?
+ if(oldstack-esp < stack[j] && stack[j] < oldstack)
+ tmpPage[j] = base - (oldstack - stack[j]);
+ else // Seems not, best leave it alone
+ tmpPage[j] = stack[j];
+ }
+ MM_FreeTemp((Uint)tmpPage);
+ i --;
+ }
+
+ return base;
+}
+
+/**
+ * \fn void MM_SetFlags(tVAddr VAddr, Uint Flags, Uint Mask)
* \brief Sets the flags on a page
*/
-void MM_SetFlags(Uint VAddr, Uint Flags, Uint Mask)
+void MM_SetFlags(tVAddr VAddr, Uint Flags, Uint Mask)
{
tPAddr *ent;
if( !(gaPageDir[VAddr >> 22] & 1) ) return ;
}
/**
- * \fn tPAddr MM_DuplicatePage(Uint VAddr)
+ * \fn tPAddr MM_DuplicatePage(tVAddr VAddr)
* \brief Duplicates a virtual page to a physical one
*/
-tPAddr MM_DuplicatePage(Uint VAddr)
+tPAddr MM_DuplicatePage(tVAddr VAddr)
{
tPAddr ret;
Uint temp;
* \brief Create a temporary memory mapping
* \todo Show Luigi Barone (C Lecturer) and see what he thinks
*/
-Uint MM_MapTemp(tPAddr PAddr)
+tVAddr MM_MapTemp(tPAddr PAddr)
{
int i;
return TEMP_MAP_ADDR + (i << 12);
}
RELEASE( &gilTempMappings );
- Proc_Yield();
+ Threads_Yield();
}
}
/**
- * \fn void MM_FreeTemp(Uint PAddr)
+ * \fn void MM_FreeTemp(tVAddr PAddr)
* \brief Free's a temp mapping
*/
-void MM_FreeTemp(Uint VAddr)
+void MM_FreeTemp(tVAddr VAddr)
{
int i = VAddr >> 12;
//ENTER("xVAddr", VAddr);
}
/**
- * \fn Uint MM_MapHWPage(tPAddr PAddr, Uint Number)
+ * \fn tVAddr MM_MapHWPage(tPAddr PAddr, Uint Number)
* \brief Allocates a contigous number of pages
*/
-Uint MM_MapHWPage(tPAddr PAddr, Uint Number)
+tVAddr MM_MapHWPage(tPAddr PAddr, Uint Number)
{
int i, j;
}
/**
- * \fn void MM_UnmapHWPage(Uint VAddr, Uint Number)
+ * \fn tVAddr MM_AllocDMA(int Pages, int MaxBits, tPAddr *PhysAddr)
+ * \brief Allocates DMA physical memory
+ * \param Pages Number of pages required
+ * \param MaxBits Maximum number of bits the physical address can have
+ * \param PhysAddr Pointer to the location to place the physical address allocated
+ * \return Virtual address allocate
+ */
+tVAddr MM_AllocDMA(int Pages, int MaxBits, tPAddr *PhysAddr)
+{
+ tPAddr maxCheck = (1 << MaxBits);
+ tPAddr phys;
+ tVAddr ret;
+
+ ENTER("iPages iMaxBits pPhysAddr", Pages, MaxBits, PhysAddr);
+
+ // Sanity Check
+ if(MaxBits < 12 || !PhysAddr) {
+ LEAVE('i', 0);
+ return 0;
+ }
+
+ // Bound
+ if(MaxBits >= PHYS_BITS) maxCheck = -1;
+
+ // Fast Allocate
+ if(Pages == 1 && MaxBits >= PHYS_BITS)
+ {
+ phys = MM_AllocPhys();
+ *PhysAddr = phys;
+ ret = MM_MapHWPage(phys, 1);
+ if(ret == 0) {
+ MM_DerefPhys(phys);
+ LEAVE('i', 0);
+ return 0;
+ }
+ LEAVE('x', ret);
+ return ret;
+ }
+
+ // Slow Allocate
+ phys = MM_AllocPhysRange(Pages);
+ // - Was it allocated?
+ if(phys == 0) {
+ LEAVE('i', 0);
+ return 0;
+ }
+ // - Check if the memory is OK
+ if(phys + (Pages-1)*0x1000 > maxCheck)
+ {
+ // Deallocate and return 0
+ for(;Pages--;phys+=0x1000)
+ MM_DerefPhys(phys);
+ LEAVE('i', 0);
+ return 0;
+ }
+
+ // Allocated successfully, now map
+ ret = MM_MapHWPage(phys, Pages);
+ if( ret == 0 ) {
+ // If it didn't map, free then return 0
+ for(;Pages--;phys+=0x1000)
+ MM_DerefPhys(phys);
+ LEAVE('i', 0);
+ return 0;
+ }
+
+ *PhysAddr = phys;
+ LEAVE('x', ret);
+ return ret;
+}
+
+/**
+ * \fn void MM_UnmapHWPage(tVAddr VAddr, Uint Number)
* \brief Unmap a hardware page
*/
-void MM_UnmapHWPage(Uint VAddr, Uint Number)
+void MM_UnmapHWPage(tVAddr VAddr, Uint Number)
{
int i, j;
// Sanity Check
EXPORT(MM_Map);
//EXPORT(MM_Unmap);
EXPORT(MM_MapHWPage);
+EXPORT(MM_AllocDMA);
EXPORT(MM_UnmapHWPage);