*
* Virtual Memory Manager
*/
+#define DEBUG 0
#include <acess.h>
#include <mm_virt.h>
+#include <threads_int.h>
+#include <proc.h>
+#include <hal_proc.h>
+
+// === DEBUG OPTIONS ===
+#define TRACE_COW 0
// === CONSTANTS ===
+#define PHYS_BITS 52 // TODO: Move out
+#define VIRT_BITS 48
+
#define PML4_SHIFT 39
#define PDP_SHIFT 30
#define PDIR_SHIFT 21
#define PTAB_SHIFT 12
-#define PF_PRESENT 0x1
-#define PF_WRITE 0x2
-#define PF_USER 0x4
-#define PF_NX 0x80000000##00000000
+#define PADDR_MASK 0x7FFFFFFF##FFFFF000
+#define PAGE_MASK ((1LL << 36)-1)
+#define TABLE_MASK ((1LL << 27)-1)
+#define PDP_MASK ((1LL << 18)-1)
+#define PML4_MASK ((1LL << 9)-1)
+
+#define PF_PRESENT 0x001
+#define PF_WRITE 0x002
+#define PF_USER 0x004
+#define PF_LARGE 0x080
+#define PF_GLOBAL 0x100
#define PF_COW 0x200
#define PF_PAGED 0x400
+#define PF_NX 0x80000000##00000000
// === MACROS ===
-#define PAGETABLE(idx) (*((tPAddr*)MM_FRACTAL_BASE+(idx)))
-#define PAGEDIR(idx) PAGETABLE((MM_FRACTAL_BASE>>12)+((idx)&0x7FFFFFF))
-#define PAGEDIRPTR(idx) PAGETABLE((MM_FRACTAL_BASE>>21)+((idx)&0x3FFFF))
-#define PAGEMAPLVL4(idx) PAGETABLE((MM_FRACTAL_BASE>>30)+((idx)&0x1FF))
+#define PAGETABLE(idx) (*((Uint64*)MM_FRACTAL_BASE+((idx)&PAGE_MASK)))
+#define PAGEDIR(idx) PAGETABLE((MM_FRACTAL_BASE>>12)+((idx)&TABLE_MASK))
+#define PAGEDIRPTR(idx) PAGEDIR((MM_FRACTAL_BASE>>21)+((idx)&PDP_MASK))
+#define PAGEMAPLVL4(idx) PAGEDIRPTR((MM_FRACTAL_BASE>>30)+((idx)&PML4_MASK))
+
+#define TMPCR3() PAGEMAPLVL4(MM_TMPFRAC_BASE>>39)
+#define TMPTABLE(idx) (*((Uint64*)MM_TMPFRAC_BASE+((idx)&PAGE_MASK)))
+#define TMPDIR(idx) PAGETABLE((MM_TMPFRAC_BASE>>12)+((idx)&TABLE_MASK))
+#define TMPDIRPTR(idx) PAGEDIR((MM_TMPFRAC_BASE>>21)+((idx)&PDP_MASK))
+#define TMPMAPLVL4(idx) PAGEDIRPTR((MM_TMPFRAC_BASE>>30)+((idx)&PML4_MASK))
+
+#define INVLPG(__addr) __asm__ __volatile__ ("invlpg (%0)"::"r"(__addr))
+#define INVLPG_ALL() __asm__ __volatile__ ("mov %cr3,%rax;\n\tmov %rax,%cr3;")
+#define INVLPG_GLOBAL() __asm__ __volatile__ ("mov %cr4,%rax;\n\txorl $0x80, %eax;\n\tmov %rax,%cr4;\n\txorl $0x80, %eax;\n\tmov %rax,%cr4")
+
+// === CONSTS ===
+//tPAddr * const gaPageTable = MM_FRACTAL_BASE;
+
+// === IMPORTS ===
+extern void Error_Backtrace(Uint IP, Uint BP);
+extern tPAddr gInitialPML4[512];
+extern void Threads_SegFault(tVAddr Addr);
+extern char _UsertextBase[];
+
+// === PROTOTYPES ===
+void MM_InitVirt(void);
+//void MM_FinishVirtualInit(void);
+void MM_int_ClonePageEnt( Uint64 *Ent, void *NextLevel, tVAddr Addr, int bTable );
+ int MM_PageFault(tVAddr Addr, Uint ErrorCode, tRegs *Regs);
+void MM_int_DumpTablesEnt(tVAddr RangeStart, size_t Length, tPAddr Expected);
+//void MM_DumpTables(tVAddr Start, tVAddr End);
+ int MM_GetPageEntryPtr(tVAddr Addr, BOOL bTemp, BOOL bAllocate, BOOL bLargePage, tPAddr **Pointer);
+ int MM_MapEx(tVAddr VAddr, tPAddr PAddr, BOOL bTemp, BOOL bLarge);
+// int MM_Map(tVAddr VAddr, tPAddr PAddr);
+void MM_Unmap(tVAddr VAddr);
+void MM_int_ClearTableLevel(tVAddr VAddr, int LevelBits, int MaxEnts);
+//void MM_ClearUser(void);
+ int MM_GetPageEntry(tVAddr Addr, tPAddr *Phys, Uint *Flags);
// === GLOBALS ===
+tMutex glMM_TempFractalLock;
+tPAddr gMM_ZeroPage;
// === CODE ===
void MM_InitVirt(void)
{
+// Log_Debug("MMVirt", "&PAGEMAPLVL4(0) = %p", &PAGEMAPLVL4(0));
+// MM_DumpTables(0, -1L);
+}
+
+void MM_FinishVirtualInit(void)
+{
+ PAGEMAPLVL4(0) = 0;
+}
+
+/**
+ * \brief Clone a page from an entry
+ * \param Ent Pointer to the entry in the PML4/PDP/PD/PT
+ * \param NextLevel Pointer to contents of the entry
+ * \param Addr Dest address
+ * \note Used in COW
+ */
+void MM_int_ClonePageEnt( Uint64 *Ent, void *NextLevel, tVAddr Addr, int bTable )
+{
+ tPAddr curpage = *Ent & PADDR_MASK;
+ int bCopied = 0;
+
+ if( MM_GetRefCount( curpage ) <= 0 ) {
+ Log_KernelPanic("MMVirt", "Page %P still marked COW, but unreferenced", curpage);
+ }
+ if( MM_GetRefCount( curpage ) == 1 )
+ {
+ *Ent &= ~PF_COW;
+ *Ent |= PF_PRESENT|PF_WRITE;
+ #if TRACE_COW
+ Log_Debug("MMVirt", "COW ent at %p (%p) only %P", Ent, NextLevel, curpage);
+ #endif
+ }
+ else
+ {
+ void *tmp;
+ tPAddr paddr;
+
+ if( !(paddr = MM_AllocPhys()) ) {
+ Threads_SegFault(Addr);
+ return ;
+ }
+
+ ASSERT(paddr != curpage);
+
+ tmp = (void*)MM_MapTemp(paddr);
+ memcpy( tmp, NextLevel, 0x1000 );
+ MM_FreeTemp( (tVAddr)tmp );
+
+ #if TRACE_COW
+ Log_Debug("MMVirt", "COW ent at %p (%p) from %P to %P", Ent, NextLevel, curpage, paddr);
+ #endif
+
+ MM_DerefPhys( curpage );
+ *Ent &= PF_USER;
+ *Ent |= paddr|PF_PRESENT|PF_WRITE;
+
+ bCopied = 1;
+ }
+ INVLPG( (tVAddr)NextLevel );
+
+ // Mark COW on contents if it's a PDPT, Dir or Table
+ if(bTable)
+ {
+ Uint64 *dp = NextLevel;
+ int i;
+ for( i = 0; i < 512; i ++ )
+ {
+ if( !(dp[i] & PF_PRESENT) )
+ continue;
+
+ if( bCopied )
+ MM_RefPhys( dp[i] & PADDR_MASK );
+ if( dp[i] & PF_WRITE ) {
+ dp[i] &= ~PF_WRITE;
+ dp[i] |= PF_COW;
+ }
+ }
+ }
+}
+
+/*
+ * \brief Called on a page fault
+ */
+int MM_PageFault(tVAddr Addr, Uint ErrorCode, tRegs *Regs)
+{
+// Log_Debug("MMVirt", "Addr = %p, ErrorCode = %x", Addr, ErrorCode);
+
+ // Catch reserved bits first
+ if( ErrorCode & 0x8 )
+ {
+ Log_Warning("MMVirt", "Reserved bits trashed!");
+ Log_Warning("MMVirt", "PML4 Ent = %P", PAGEMAPLVL4(Addr>>39));
+ if( !(PAGEMAPLVL4(Addr>>39) & PF_PRESENT) ) goto print_done;
+ Log_Warning("MMVirt", "PDP Ent = %P", PAGEDIRPTR(Addr>>30));
+ if( !(PAGEDIRPTR(Addr>>30) & PF_PRESENT) ) goto print_done;
+ Log_Warning("MMVirt", "PDir Ent = %P", PAGEDIR(Addr>>21));
+ if( !(PAGEDIR(Addr>>21) & PF_PRESENT) ) goto print_done;
+ Log_Warning("MMVirt", "PTable Ent = %P", PAGETABLE(Addr>>12));
+ if( !(PAGETABLE(Addr>>12) & PF_PRESENT) ) goto print_done;
+ print_done:
+
+ for(;;);
+ }
+
+ // TODO: Implement Copy-on-Write
+ #if 1
+ if( PAGEMAPLVL4(Addr>>39) & PF_PRESENT
+ && PAGEDIRPTR (Addr>>30) & PF_PRESENT
+ && PAGEDIR (Addr>>21) & PF_PRESENT
+ && PAGETABLE (Addr>>12) & PF_PRESENT )
+ {
+ // PML4 Entry
+ if( PAGEMAPLVL4(Addr>>39) & PF_COW )
+ {
+ tPAddr *dp = &PAGEDIRPTR((Addr>>39)*512);
+ MM_int_ClonePageEnt( &PAGEMAPLVL4(Addr>>39), dp, Addr, 1 );
+// MM_DumpTables(Addr>>39 << 39, (((Addr>>39) + 1) << 39) - 1);
+ }
+ // PDP Entry
+ if( PAGEDIRPTR(Addr>>30) & PF_COW )
+ {
+ tPAddr *dp = &PAGEDIR( (Addr>>30)*512 );
+ MM_int_ClonePageEnt( &PAGEDIRPTR(Addr>>30), dp, Addr, 1 );
+// MM_DumpTables(Addr>>30 << 30, (((Addr>>30) + 1) << 30) - 1);
+ }
+ // PD Entry
+ if( PAGEDIR(Addr>>21) & PF_COW )
+ {
+ tPAddr *dp = &PAGETABLE( (Addr>>21)*512 );
+ MM_int_ClonePageEnt( &PAGEDIR(Addr>>21), dp, Addr, 1 );
+// MM_DumpTables(Addr>>21 << 21, (((Addr>>21) + 1) << 21) - 1);
+ }
+ // PT Entry
+ if( PAGETABLE(Addr>>12) & PF_COW )
+ {
+ MM_int_ClonePageEnt( &PAGETABLE(Addr>>12), (void*)(Addr & ~0xFFF), Addr, 0 );
+ INVLPG( Addr & ~0xFFF );
+ return 0;
+ }
+ }
+ #endif
+
+ // If it was a user, tell the thread handler
+ if(ErrorCode & 4) {
+ Warning("User %s %s memory%s",
+ (ErrorCode&2?"write to":"read from"),
+ (ErrorCode&1?"bad/locked":"non-present"),
+ (ErrorCode&16?" (Instruction Fetch)":"")
+ );
+ Warning("User Pagefault: Instruction at %04x:%p accessed %p",
+ Regs->CS, Regs->RIP, Addr);
+ __asm__ __volatile__ ("sti"); // Restart IRQs
+ Error_Backtrace(Regs->RIP, Regs->RBP);
+ Threads_SegFault(Addr);
+ return 0;
+ }
+
+ // Kernel #PF
+ Debug_KernelPanic();
+ // -- Check Error Code --
+ if(ErrorCode & 8)
+ Warning("Reserved Bits Trashed!");
+ else
+ {
+ Warning("Kernel %s %s memory%s",
+ (ErrorCode&2?"write to":"read from"),
+ (ErrorCode&1?"bad/locked":"non-present"),
+ (ErrorCode&16?" (Instruction Fetch)":"")
+ );
+ }
+
+ Log("Thread %i - Code at %p accessed %p", Threads_GetTID(), Regs->RIP, Addr);
+ // Print Stack Backtrace
+ Error_Backtrace(Regs->RIP, Regs->RBP);
+ MM_DumpTables(0, -1);
+
+ return 1;
+}
+
+void MM_int_DumpTablesEnt(tVAddr RangeStart, size_t Length, tPAddr Expected)
+{
+ #define CANOICAL(addr) ((addr)&0x800000000000?(addr)|0xFFFF000000000000:(addr))
+ LogF("%016llx => ", CANOICAL(RangeStart));
+// LogF("%6llx %6llx %6llx %016llx => ",
+// MM_GetPhysAddr( (tVAddr)&PAGEDIRPTR(RangeStart>>30) ),
+// MM_GetPhysAddr( (tVAddr)&PAGEDIR(RangeStart>>21) ),
+// MM_GetPhysAddr( (tVAddr)&PAGETABLE(RangeStart>>12) ),
+// CANOICAL(RangeStart)
+// );
+ if( gMM_ZeroPage && (PAGETABLE(RangeStart>>12) & PADDR_MASK) == gMM_ZeroPage )
+ LogF("%13s", "zero" );
+ else
+ LogF("%13llx", PAGETABLE(RangeStart>>12) & PADDR_MASK );
+ LogF(" : 0x%6llx (%c%c%c%c%c%c)\r\n",
+ Length,
+ (Expected & PF_GLOBAL ? 'G' : '-'),
+ (Expected & PF_NX ? '-' : 'x'),
+ (Expected & PF_PAGED ? 'p' : '-'),
+ (Expected & PF_COW ? 'C' : '-'),
+ (Expected & PF_USER ? 'U' : '-'),
+ (Expected & PF_WRITE ? 'W' : '-')
+ );
+ #undef CANOICAL
}
/**
- * \brief Map a physical page to a virtual one
+ * \brief Dumps the layout of the page tables
*/
-int MM_Map(tVAddr VAddr, tPAddr PAddr)
+void MM_DumpTables(tVAddr Start, tVAddr End)
{
- tPAddr tmp;
+ const tPAddr FIXED_BITS = PF_PRESENT|PF_WRITE|PF_USER|PF_COW|PF_PAGED|PF_NX|PF_GLOBAL;
+ const tPAddr CHANGEABLE_BITS = ~FIXED_BITS & 0xFFF;
+ const tPAddr MASK = ~CHANGEABLE_BITS; // Physical address and access bits
+ tVAddr rangeStart = 0;
+ tPAddr expected = CHANGEABLE_BITS; // CHANGEABLE_BITS is used because it's not a vaild value
+ tVAddr curPos;
+ Uint page;
+ tPAddr expected_pml4 = PF_WRITE|PF_USER;
+ tPAddr expected_pdp = PF_WRITE|PF_USER;
+ tPAddr expected_pd = PF_WRITE|PF_USER;
+
+ Log("Table Entries: (%p to %p)", Start, End);
- // Check PML4
- if( !(PAGEMAPLVL4(VAddr >> 39) & 1) )
+ End &= (1L << 48) - 1;
+
+ Start >>= 12; End >>= 12;
+
+ for(page = Start, curPos = Start<<12;
+ page < End;
+ curPos += 0x1000, page++)
{
- tmp = MM_AllocPhys();
- if(!tmp) return 0;
- PAGEMAPLVL4(VAddr >> 39) = tmp | 3;
- memset( &PAGEDIRPTR( (VAddr>>39)<<9 ), 0, 4096 );
+ //Debug("&PAGEMAPLVL4(%i page>>27) = %p", page>>27, &PAGEMAPLVL4(page>>27));
+ //Debug("&PAGEDIRPTR(%i page>>18) = %p", page>>18, &PAGEDIRPTR(page>>18));
+ //Debug("&PAGEDIR(%i page>>9) = %p", page>>9, &PAGEDIR(page>>9));
+ //Debug("&PAGETABLE(%i page) = %p", page, &PAGETABLE(page));
+
+ // End of a range
+ if(!(PAGEMAPLVL4(page>>27) & PF_PRESENT)
+ || (PAGEMAPLVL4(page>>27) & FIXED_BITS) != expected_pml4
+ || !(PAGEDIRPTR(page>>18) & PF_PRESENT)
+ || (PAGEDIRPTR(page>>18) & FIXED_BITS) != expected_pdp
+ || !(PAGEDIR(page>>9) & PF_PRESENT)
+ || (PAGEDIR(page>>9) & FIXED_BITS) != expected_pd
+ || !(PAGETABLE(page) & PF_PRESENT)
+ || (PAGETABLE(page) & MASK) != expected)
+ {
+ if(expected != CHANGEABLE_BITS)
+ {
+ // Merge
+ expected &= expected_pml4 | ~(PF_WRITE|PF_USER);
+ expected &= expected_pdp | ~(PF_WRITE|PF_USER);
+ expected &= expected_pd | ~(PF_WRITE|PF_USER);
+ expected |= expected_pml4 & PF_NX;
+ expected |= expected_pdp & PF_NX;
+ expected |= expected_pd & PF_NX;
+ Log("expected (pml4 = %x, pdp = %x, pd = %x)",
+ expected_pml4, expected_pdp, expected_pd);
+ // Dump
+ MM_int_DumpTablesEnt( rangeStart, curPos - rangeStart, expected );
+ expected = CHANGEABLE_BITS;
+ }
+
+ if( curPos == 0x800000000000L )
+ curPos = 0xFFFF800000000000L;
+
+ if( !(PAGEMAPLVL4(page>>27) & PF_PRESENT) ) {
+ page += (1 << 27) - 1;
+ curPos += (1L << 39) - 0x1000;
+ continue;
+ }
+ if( !(PAGEDIRPTR(page>>18) & PF_PRESENT) ) {
+ page += (1 << 18) - 1;
+ curPos += (1L << 30) - 0x1000;
+ continue;
+ }
+ if( !(PAGEDIR(page>>9) & PF_PRESENT) ) {
+ page += (1 << 9) - 1;
+ curPos += (1L << 21) - 0x1000;
+ continue;
+ }
+ if( !(PAGETABLE(page) & PF_PRESENT) ) continue;
+
+ expected = (PAGETABLE(page) & MASK);
+ expected_pml4 = (PAGEMAPLVL4(page>>27) & FIXED_BITS);
+ expected_pdp = (PAGEDIRPTR (page>>18) & FIXED_BITS);
+ expected_pd = (PAGEDIR (page>> 9) & FIXED_BITS);
+ rangeStart = curPos;
+ }
+ if(gMM_ZeroPage && (expected & PADDR_MASK) == gMM_ZeroPage )
+ expected = expected;
+ else if(expected != CHANGEABLE_BITS)
+ expected += 0x1000;
}
- // Check PDP
- if( !(PAGEDIRPTR(VAddr >> 30) & 1) )
+ if(expected != CHANGEABLE_BITS) {
+ // Merge
+
+ // Dump
+ MM_int_DumpTablesEnt( rangeStart, curPos - rangeStart, expected );
+ expected = 0;
+ }
+}
+
+/**
+ * \brief Get a pointer to a page entry
+ * \param Addr Virtual Address
+ * \param bTemp Use the Temporary fractal mapping
+ * \param bAllocate Allocate entries
+ * \param bLargePage Request a large page
+ * \param Pointer Location to place the calculated pointer
+ * \return Page size, or -ve on error
+ */
+int MM_GetPageEntryPtr(tVAddr Addr, BOOL bTemp, BOOL bAllocate, BOOL bLargePage, tPAddr **Pointer)
+{
+ tPAddr *pmlevels[4];
+ tPAddr tmp;
+ int i, size;
+
+ #define BITMASK(bits) ( (1LL << (bits))-1 )
+
+ if( bTemp )
{
- tmp = MM_AllocPhys();
- if(!tmp) return 0;
- PAGEDIRPTR(VAddr >> 30) = tmp | 3;
- memset( &PAGEDIR( (VAddr>>30)<<9 ), 0, 4096 );
+ pmlevels[3] = &TMPTABLE(0); // Page Table
+ pmlevels[2] = &TMPDIR(0); // PDIR
+ pmlevels[1] = &TMPDIRPTR(0); // PDPT
+ pmlevels[0] = &TMPMAPLVL4(0); // PML4
+ }
+ else
+ {
+ pmlevels[3] = (void*)MM_FRACTAL_BASE; // Page Table
+ pmlevels[2] = &pmlevels[3][(MM_FRACTAL_BASE>>12)&BITMASK(VIRT_BITS-12)]; // PDIR
+ pmlevels[1] = &pmlevels[2][(MM_FRACTAL_BASE>>21)&BITMASK(VIRT_BITS-21)]; // PDPT
+ pmlevels[0] = &pmlevels[1][(MM_FRACTAL_BASE>>30)&BITMASK(VIRT_BITS-30)]; // PML4
}
- // Check Page Dir
- if( !(PAGEDIR(VAddr >> 21) & 1) )
+ // Mask address
+ Addr &= (1ULL << 48)-1;
+
+ for( size = 39, i = 0; size > 12; size -= 9, i ++ )
{
- tmp = MM_AllocPhys();
- if(!tmp) return 0;
- PAGEDIR(VAddr >> 21) = tmp | 3;
- memset( &PAGETABLE( (VAddr>>21)<<9 ), 0, 4096 );
+ Uint64 *ent = &pmlevels[i][Addr >> size];
+// INVLPG( &pmlevels[i][ (Addr >> ADDR_SIZES[i]) &
+
+ // Check for a free large page slot
+ // TODO: Better support with selectable levels
+ if( (Addr & ((1ULL << size)-1)) == 0 && bLargePage )
+ {
+ if(Pointer) *Pointer = ent;
+ return size;
+ }
+ // Allocate an entry if required
+ if( !(*ent & PF_PRESENT) )
+ {
+ if( !bAllocate ) return -4; // If allocation is not requested, error
+ if( !(tmp = MM_AllocPhys()) ) return -2;
+ *ent = tmp | 3;
+ if( Addr < 0x800000000000 )
+ *ent |= PF_USER;
+ INVLPG( &pmlevels[i+1][ (Addr>>size)*512 ] );
+ memset( &pmlevels[i+1][ (Addr>>size)*512 ], 0, 0x1000 );
+ LOG("Init PML%i ent 0x%x %p with %P (*ent = %P)", 4 - i,
+ Addr>>size, (Addr>>size) << size, tmp, *ent);
+ }
+ // Catch large pages
+ else if( *ent & PF_LARGE )
+ {
+ // Alignment
+ if( (Addr & ((1ULL << size)-1)) != 0 ) return -3;
+ if(Pointer) *Pointer = ent;
+ return size; // Large page warning
+ }
}
- // Check if this virtual address is already mapped
- if( PAGETABLE(VAddr >> 12) & 1 )
- return 0;
+ // And, set the page table entry
+ if(Pointer) *Pointer = &pmlevels[i][Addr >> size];
+ return size;
+}
+
+/**
+ * \brief Map a physical page to a virtual one
+ * \param VAddr Target virtual address
+ * \param PAddr Physical address of page
+ * \param bTemp Use tempoary mappings
+ * \param bLarge Treat as a large page
+ */
+int MM_MapEx(tVAddr VAddr, tPAddr PAddr, BOOL bTemp, BOOL bLarge)
+{
+ tPAddr *ent;
+ int rv;
+
+ ENTER("pVAddr PPAddr", VAddr, PAddr);
- PAGETABLE(VAddr >> 12) = PAddr | 3;
+ // Get page pointer (Allow allocating)
+ rv = MM_GetPageEntryPtr(VAddr, bTemp, 1, bLarge, &ent);
+ if(rv < 0) LEAVE_RET('i', 0);
+ if( *ent & 1 ) LEAVE_RET('i', 0);
+
+ *ent = PAddr | 3;
+
+ if( VAddr < 0x800000000000 )
+ *ent |= PF_USER;
+
+ INVLPG( VAddr );
+
+ LEAVE('i', 1);
return 1;
}
+/**
+ * \brief Map a physical page to a virtual one
+ * \param VAddr Target virtual address
+ * \param PAddr Physical address of page
+ */
+int MM_Map(tVAddr VAddr, tPAddr PAddr)
+{
+ return MM_MapEx(VAddr, PAddr, 0, 0);
+}
+
+/**
+ * \brief Removed a mapped page
+ */
+void MM_Unmap(tVAddr VAddr)
+{
+ // Check PML4
+ if( !(PAGEMAPLVL4(VAddr >> 39) & 1) ) return ;
+ // Check PDP
+ if( !(PAGEDIRPTR(VAddr >> 30) & 1) ) return ;
+ // Check Page Dir
+ if( !(PAGEDIR(VAddr >> 21) & 1) ) return ;
+
+ PAGETABLE(VAddr >> PTAB_SHIFT) = 0;
+ INVLPG( VAddr );
+}
+
/**
* \brief Allocate a block of memory at the specified virtual address
*/
{
tPAddr ret;
+ ENTER("xVAddr", VAddr);
+
+ // Ensure the tables are allocated before the page (keeps things neat)
+ MM_GetPageEntryPtr(VAddr, 0, 1, 0, NULL);
+
+ // Allocate the page
ret = MM_AllocPhys();
- if(!ret) return 0;
+ LOG("ret = %x", ret);
+ if(!ret) LEAVE_RET('i', 0);
if( !MM_Map(VAddr, ret) )
{
+ Warning("MM_Allocate: Unable to map. Strange, we should have errored earlier");
MM_DerefPhys(ret);
+ LEAVE('i');
return 0;
}
+ LEAVE('X', ret);
+ return ret;
+}
+
+tPAddr MM_AllocateZero(tVAddr VAddr)
+{
+ tPAddr ret = gMM_ZeroPage;
+
+ MM_GetPageEntryPtr(VAddr, 0, 1, 0, NULL);
+
+ if(!gMM_ZeroPage) {
+ ret = gMM_ZeroPage = MM_AllocPhys();
+ MM_RefPhys(ret); // Don't free this please
+ MM_Map(VAddr, ret);
+ memset((void*)VAddr, 0, 0x1000);
+ }
+ else {
+ MM_Map(VAddr, ret);
+ }
+ MM_RefPhys(ret); // Refernce for this map
+ MM_SetFlags(VAddr, MM_PFLAG_COW, MM_PFLAG_COW);
+ return ret;
+}
+
+/**
+ * \brief Deallocate a page at a virtual address
+ */
+void MM_Deallocate(tVAddr VAddr)
+{
+ tPAddr phys;
+
+ phys = MM_GetPhysAddr(VAddr);
+ if(!phys) return ;
+
+ MM_Unmap(VAddr);
+
+ MM_DerefPhys(phys);
+}
+
+/**
+ * \brief Get the page table entry of a virtual address
+ * \param Addr Virtual Address
+ * \param Phys Location to put the physical address
+ * \param Flags Flags on the entry (set to zero if unmapped)
+ * \return Size of the entry (in address bits) - 12 = 4KiB page
+ */
+int MM_GetPageEntry(tVAddr Addr, tPAddr *Phys, Uint *Flags)
+{
+ tPAddr *ptr;
+ int ret;
+
+ if(!Phys || !Flags) return 0;
+
+ ret = MM_GetPageEntryPtr(Addr, 0, 0, 0, &ptr);
+ if( ret < 0 ) return 0;
+
+ *Phys = *ptr & PADDR_MASK;
+ *Flags = *ptr & 0xFFF;
return ret;
}
*/
tPAddr MM_GetPhysAddr(tVAddr Addr)
{
- if( !(PAGEMAPLVL4(Addr >> 39) & 1) )
- return 0;
- if( !(PAGEDIRPTR(Addr >> 30) & 1) )
- return 0;
- if( !(PAGEDIR(Addr >> 21) & 1) )
- return 0;
- if( !(PAGETABLE(Addr >> 12) & 1) )
- return 0;
+ tPAddr *ptr;
+ int ret;
+
+ ret = MM_GetPageEntryPtr(Addr, 0, 0, 0, &ptr);
+ if( ret < 0 ) return 0;
+
+ if( !(*ptr & 1) ) return 0;
- return (PAGETABLE(Addr >> 12) & ~0xFFF) | (Addr & 0xFFF);
+ return (*ptr & PADDR_MASK) | (Addr & 0xFFF);
}
/**
void MM_SetFlags(tVAddr VAddr, Uint Flags, Uint Mask)
{
tPAddr *ent;
+ int rv;
- // Validity Check
- if( !(PAGEMAPLVL4(VAddr >> 39) & 1) )
- return ;
- if( !(PAGEDIRPTR(VAddr >> 30) & 1) )
- return ;
- if( !(PAGEDIR(VAddr >> 21) & 1) )
- return ;
- if( !(PAGETABLE(VAddr >> 12) & 1) )
- return ;
+ // Get pointer
+ rv = MM_GetPageEntryPtr(VAddr, 0, 0, 0, &ent);
+ if(rv < 0) return ;
- // Set Flags
- ent = &PAGETABLE(VAddr >> 12);
+ // Ensure the entry is valid
+ if( !(*ent & 1) ) return ;
// Read-Only
if( Mask & MM_PFLAG_RO )
if( Flags & MM_PFLAG_COW ) {
*ent &= ~PF_WRITE;
*ent |= PF_COW;
+ INVLPG_ALL();
}
else {
*ent &= ~PF_COW;
}
}
+/**
+ * \brief Get the flags applied to a page
+ */
Uint MM_GetFlags(tVAddr VAddr)
{
tPAddr *ent;
- Uint ret = 0;
+ int rv, ret = 0;
- // Validity Check
- if( !(PAGEMAPLVL4(VAddr >> 39) & 1) )
- return 0;
- if( !(PAGEDIRPTR(VAddr >> 30) & 1) )
- return 0;
- if( !(PAGEDIR(VAddr >> 21) & 1) )
- return 0;
- if( !(PAGETABLE(VAddr >> 12) & 1) )
- return 0;
+ rv = MM_GetPageEntryPtr(VAddr, 0, 0, 0, &ent);
+ if(rv < 0) return 0;
- // Set Flags
- ent = &PAGETABLE(VAddr >> 12);
+ if( !(*ent & 1) ) return 0;
// Read-Only
if( !(*ent & PF_WRITE) ) ret |= MM_PFLAG_RO;
return ret;
}
+
+/**
+ * \brief Check if the provided buffer is valid
+ * \return Boolean valid
+ */
+int MM_IsValidBuffer(tVAddr Addr, size_t Size)
+{
+ int bIsUser;
+ Uint64 pml4, pdp, dir, tab;
+
+ Size += Addr & (PAGE_SIZE-1);
+ Addr &= ~(PAGE_SIZE-1);
+ Addr &= ((1UL << 48)-1); // Clap to address space
+
+ pml4 = Addr >> 39;
+ pdp = Addr >> 30;
+ dir = Addr >> 21;
+ tab = Addr >> 12;
+
+ if( !(PAGEMAPLVL4(pml4) & 1) ) return 0;
+ if( !(PAGEDIRPTR(pdp) & 1) ) return 0;
+ if( !(PAGEDIR(dir) & 1) ) return 0;
+ if( !(PAGETABLE(tab) & 1) ) return 0;
+
+ bIsUser = !!(PAGETABLE(tab) & PF_USER);
+
+ while( Size >= PAGE_SIZE )
+ {
+ if( (tab & 511) == 0 )
+ {
+ dir ++;
+ if( ((dir >> 9) & 511) == 0 )
+ {
+ pdp ++;
+ if( ((pdp >> 18) & 511) == 0 )
+ {
+ pml4 ++;
+ if( !(PAGEMAPLVL4(pml4) & 1) ) return 0;
+ }
+ if( !(PAGEDIRPTR(pdp) & 1) ) return 0;
+ }
+ if( !(PAGEDIR(dir) & 1) ) return 0;
+ }
+
+ if( !(PAGETABLE(tab) & 1) ) return 0;
+ if( bIsUser && !(PAGETABLE(tab) & PF_USER) ) return 0;
+
+ tab ++;
+ Size -= PAGE_SIZE;
+ }
+ return 1;
+}
+
+// --- Hardware Mappings ---
+/**
+ * \brief Map a range of hardware pages
+ */
+tVAddr MM_MapHWPages(tPAddr PAddr, Uint Number)
+{
+ tVAddr ret;
+ int num;
+
+ //TODO: Add speedups (memory of first possible free)
+ for( ret = MM_HWMAP_BASE; ret < MM_HWMAP_TOP; ret += 0x1000 )
+ {
+ for( num = Number; num -- && ret < MM_HWMAP_TOP; ret += 0x1000 )
+ {
+ if( MM_GetPhysAddr(ret) != 0 ) break;
+ }
+ if( num >= 0 ) continue;
+
+// Log_Debug("MMVirt", "Mapping %i pages to %p (base %P)", Number, ret-Number*0x1000, PAddr);
+
+ PAddr += 0x1000 * Number;
+
+ while( Number -- )
+ {
+ ret -= 0x1000;
+ PAddr -= 0x1000;
+ MM_Map(ret, PAddr);
+ MM_RefPhys(PAddr);
+ }
+
+ return ret;
+ }
+
+ Log_Error("MM", "MM_MapHWPages - No space for %i pages", Number);
+ return 0;
+}
+
+/**
+ * \brief Free a range of hardware pages
+ */
+void MM_UnmapHWPages(tVAddr VAddr, Uint Number)
+{
+// Log_KernelPanic("MM", "TODO: Implement MM_UnmapHWPages");
+ while( Number -- )
+ {
+ MM_DerefPhys( MM_GetPhysAddr(VAddr) );
+ MM_Unmap(VAddr);
+ VAddr += 0x1000;
+ }
+}
+
+
+/**
+ * \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 phys;
+ tVAddr ret;
+
+ // Sanity Check
+ if(MaxBits < 12 || !PhysAddr) return 0;
+
+ // Fast Allocate
+ if(Pages == 1 && MaxBits >= PHYS_BITS)
+ {
+ phys = MM_AllocPhys();
+ *PhysAddr = phys;
+ ret = MM_MapHWPages(phys, 1);
+ MM_DerefPhys(phys);
+ return ret;
+ }
+
+ // Slow Allocate
+ phys = MM_AllocPhysRange(Pages, MaxBits);
+ // - Was it allocated?
+ if(phys == 0) return 0;
+
+ // Allocated successfully, now map
+ ret = MM_MapHWPages(phys, Pages);
+ // MapHWPages references the pages, so deref them back down to 1
+ for(;Pages--;phys+=0x1000)
+ MM_DerefPhys(phys);
+ if( ret == 0 ) {
+ // If it didn't map, free then return 0
+ return 0;
+ }
+
+ *PhysAddr = phys;
+ return ret;
+}
+
+// --- Tempory Mappings ---
+tVAddr MM_MapTemp(tPAddr PAddr)
+{
+ const int max_slots = (MM_TMPMAP_END - MM_TMPMAP_BASE) / PAGE_SIZE;
+ tVAddr ret = MM_TMPMAP_BASE;
+ int i;
+
+ for( i = 0; i < max_slots; i ++, ret += PAGE_SIZE )
+ {
+ tPAddr *ent;
+ if( MM_GetPageEntryPtr( ret, 0, 1, 0, &ent) < 0 ) {
+ continue ;
+ }
+
+ if( *ent & 1 )
+ continue ;
+
+ *ent = PAddr | 3;
+ MM_RefPhys(PAddr);
+ INVLPG(ret);
+ return ret;
+ }
+ return 0;
+}
+
+void MM_FreeTemp(tVAddr VAddr)
+{
+ MM_Deallocate(VAddr);
+ return ;
+}
+
+
+// --- Address Space Clone --
+tPAddr MM_Clone(void)
+{
+ tPAddr ret;
+ int i;
+ tVAddr kstackbase;
+
+ // #1 Create a copy of the PML4
+ ret = MM_AllocPhys();
+ if(!ret) return 0;
+
+ // #2 Alter the fractal pointer
+ Mutex_Acquire(&glMM_TempFractalLock);
+ TMPCR3() = ret | 3;
+ INVLPG_ALL();
+
+ // #3 Set Copy-On-Write to all user pages
+ if( Threads_GetPID() != 0 )
+ {
+ for( i = 0; i < 256; i ++)
+ {
+ if( PAGEMAPLVL4(i) & PF_WRITE ) {
+ PAGEMAPLVL4(i) |= PF_COW;
+ PAGEMAPLVL4(i) &= ~PF_WRITE;
+ }
+
+ TMPMAPLVL4(i) = PAGEMAPLVL4(i);
+// Log_Debug("MM", "TMPMAPLVL4(%i) = 0x%016llx", i, TMPMAPLVL4(i));
+ if( !(TMPMAPLVL4(i) & PF_PRESENT) ) continue ;
+
+ MM_RefPhys( TMPMAPLVL4(i) & PADDR_MASK );
+ }
+ }
+ else
+ {
+ for( i = 0; i < 256; i ++ )
+ {
+ TMPMAPLVL4(i) = 0;
+ }
+ }
+
+ // #4 Map in kernel pages
+ for( i = 256; i < 512; i ++ )
+ {
+ // Skip addresses:
+ // 320 0xFFFFA.... - Kernel Stacks
+ if( i == MM_KSTACK_BASE>>39 ) continue;
+ // 509 0xFFFFFE0.. - Fractal mapping
+ if( i == MM_FRACTAL_BASE>>39 ) continue;
+ // 510 0xFFFFFE8.. - Temp fractal mapping
+ if( i == MM_TMPFRAC_BASE>>39 ) continue;
+
+ TMPMAPLVL4(i) = PAGEMAPLVL4(i);
+ if( TMPMAPLVL4(i) & 1 )
+ MM_RefPhys( TMPMAPLVL4(i) & PADDR_MASK );
+ }
+
+ // Mark Per-Process data as COW
+ TMPMAPLVL4(MM_PPD_BASE>>39) |= PF_COW;
+ TMPMAPLVL4(MM_PPD_BASE>>39) &= ~PF_WRITE;
+
+ // #5 Set fractal mapping
+ TMPMAPLVL4(MM_FRACTAL_BASE>>39) = ret | 3; // Main
+ TMPMAPLVL4(MM_TMPFRAC_BASE>>39) = 0; // Temp
+
+ // #6 Create kernel stack
+ // tThread->KernelStack is the top
+ // There is 1 guard page below the stack
+ kstackbase = Proc_GetCurThread()->KernelStack - KERNEL_STACK_SIZE;
+
+ // Clone stack
+ TMPMAPLVL4(MM_KSTACK_BASE >> PML4_SHIFT) = 0;
+ for( i = 1; i < KERNEL_STACK_SIZE/0x1000; i ++ )
+ {
+ tPAddr phys = MM_AllocPhys();
+ tVAddr tmpmapping;
+ MM_MapEx(kstackbase+i*0x1000, phys, 1, 0);
+
+ tmpmapping = MM_MapTemp(phys);
+ if( MM_GetPhysAddr( kstackbase+i*0x1000 ) )
+ memcpy((void*)tmpmapping, (void*)(kstackbase+i*0x1000), 0x1000);
+ else
+ memset((void*)tmpmapping, 0, 0x1000);
+// if( i == 0xF )
+// Debug_HexDump("MM_Clone: *tmpmapping = ", (void*)tmpmapping, 0x1000);
+ MM_FreeTemp(tmpmapping);
+ }
+
+// MAGIC_BREAK();
+
+ // #7 Return
+ TMPCR3() = 0;
+ INVLPG_ALL();
+ Mutex_Release(&glMM_TempFractalLock);
+// Log("MM_Clone: RETURN %P", ret);
+ return ret;
+}
+
+void MM_int_ClearTableLevel(tVAddr VAddr, int LevelBits, int MaxEnts)
+{
+ Uint64 * const table_bases[] = {&PAGETABLE(0), &PAGEDIR(0), &PAGEDIRPTR(0), &PAGEMAPLVL4(0)};
+ Uint64 *table = table_bases[(LevelBits-12)/9] + (VAddr >> LevelBits);
+ int i;
+// Log("MM_int_ClearTableLevel: (VAddr=%p, LevelBits=%i, MaxEnts=%i)", VAddr, LevelBits, MaxEnts);
+ for( i = 0; i < MaxEnts; i ++ )
+ {
+ // Skip non-present tables
+ if( !(table[i] & PF_PRESENT) ) {
+ table[i] = 0;
+ continue ;
+ }
+
+ if( (table[i] & PF_COW) && MM_GetRefCount(table[i] & PADDR_MASK) > 1 ) {
+ MM_DerefPhys(table[i] & PADDR_MASK);
+ table[i] = 0;
+ continue ;
+ }
+ // Clear table contents (if it is a table)
+ if( LevelBits > 12 )
+ MM_int_ClearTableLevel(VAddr + ((tVAddr)i << LevelBits), LevelBits-9, 512);
+ MM_DerefPhys(table[i] & PADDR_MASK);
+ table[i] = 0;
+ }
+}
+
+void MM_ClearUser(void)
+{
+ MM_int_ClearTableLevel(0, 39, 256);
+}
+
+tVAddr MM_NewWorkerStack(void *StackData, size_t StackSize)
+{
+ tVAddr ret;
+ tPAddr phys;
+ int i;
+
+ // #1 Set temp fractal to PID0
+ Mutex_Acquire(&glMM_TempFractalLock);
+ TMPCR3() = ((tPAddr)gInitialPML4 - KERNEL_BASE) | 3;
+ INVLPG_ALL();
+
+ // #2 Scan for a free stack addresss < 2^47
+ for(ret = 0x100000; ret < (1ULL << 47); ret += KERNEL_STACK_SIZE)
+ {
+ tPAddr *ptr;
+ if( MM_GetPageEntryPtr(ret, 1, 0, 0, &ptr) <= 0 ) break;
+ if( !(*ptr & 1) ) break;
+ }
+ if( ret >= (1ULL << 47) ) {
+ Mutex_Release(&glMM_TempFractalLock);
+ return 0;
+ }
+
+ // #3 Map all save the last page in the range
+ // - This acts as as guard page
+ MM_GetPageEntryPtr(ret, 1, 1, 0, NULL); // Make sure tree is allocated
+ for( i = 0; i < KERNEL_STACK_SIZE/0x1000 - 1; i ++ )
+ {
+ phys = MM_AllocPhys();
+ if(!phys) {
+ // TODO: Clean up
+ Log_Error("MM", "MM_NewWorkerStack - Unable to allocate page");
+ return 0;
+ }
+ MM_MapEx(ret + i*0x1000, phys, 1, 0);
+ MM_SetFlags(ret + i*0x1000, MM_PFLAG_KERNEL|MM_PFLAG_RO, MM_PFLAG_KERNEL);
+ }
+
+ // Copy data
+ if( StackSize > 0x1000 ) {
+ Log_Error("MM", "MM_NewWorkerStack: StackSize(0x%x) > 0x1000, cbf handling", StackSize);
+ }
+ else {
+ tVAddr tmp_addr, dest;
+ tmp_addr = MM_MapTemp(phys);
+ dest = tmp_addr + (0x1000 - StackSize);
+ memcpy( (void*)dest, StackData, StackSize );
+ Log_Debug("MM", "MM_NewWorkerStack: %p->%p %i bytes (i=%i)", StackData, dest, StackSize, i);
+ Log_Debug("MM", "MM_NewWorkerStack: ret = %p", ret);
+ MM_FreeTemp(tmp_addr);
+ }
+
+ TMPCR3() = 0;
+ Mutex_Release(&glMM_TempFractalLock);
+
+ return ret + i*0x1000;
+}
+
+/**
+ * \brief Allocate a new kernel stack
+ */
+tVAddr MM_NewKStack(void)
+{
+ tVAddr base = MM_KSTACK_BASE;
+ Uint i;
+ for( ; base < MM_KSTACK_TOP; base += KERNEL_STACK_SIZE )
+ {
+ if(MM_GetPhysAddr(base+KERNEL_STACK_SIZE-0x1000) != 0)
+ continue;
+
+ //Log("MM_NewKStack: Found one at %p", base + KERNEL_STACK_SIZE);
+ for( i = 0x1000; i < KERNEL_STACK_SIZE; i += 0x1000)
+ {
+ if( !MM_Allocate(base+i) )
+ {
+ Log_Warning("MM", "MM_NewKStack - Allocation failed");
+ for( i -= 0x1000; i; i -= 0x1000)
+ MM_Deallocate(base+i);
+ return 0;
+ }
+ }
+
+ return base + KERNEL_STACK_SIZE;
+ }
+ Log_Warning("MM", "MM_NewKStack - No address space left\n");
+ return 0;
+}