4 * Virtual Memory Manager
15 #define PADDR_MASK 0x7FFFFFFF##FFFFF000
17 #define PF_PRESENT 0x1
21 #define PF_PAGED 0x400
22 #define PF_NX 0x80000000##00000000
25 #define PAGETABLE(idx) (*((tPAddr*)MM_FRACTAL_BASE+(idx)))
26 #define PAGEDIR(idx) PAGETABLE((MM_FRACTAL_BASE>>12)+((idx)&0x7FFFFFF))
27 #define PAGEDIRPTR(idx) PAGEDIR((MM_FRACTAL_BASE>>21)+((idx)&0x3FFFF))
28 #define PAGEMAPLVL4(idx) PAGEDIRPTR((MM_FRACTAL_BASE>>30)+((idx)&0x1FF))
33 void MM_InitVirt(void)
38 void MM_FinishVirtualInit(void)
44 * \brief Map a physical page to a virtual one
46 int MM_Map(tVAddr VAddr, tPAddr PAddr)
51 if( !(PAGEMAPLVL4(VAddr >> 39) & 1) )
55 PAGEMAPLVL4(VAddr >> 39) = tmp | 3;
56 memset( &PAGEDIRPTR( (VAddr>>39)<<9 ), 0, 4096 );
60 if( !(PAGEDIRPTR(VAddr >> 30) & 1) )
64 PAGEDIRPTR(VAddr >> 30) = tmp | 3;
65 memset( &PAGEDIR( (VAddr>>30)<<9 ), 0, 4096 );
69 if( !(PAGEDIR(VAddr >> 21) & 1) )
73 PAGEDIR(VAddr >> 21) = tmp | 3;
74 memset( &PAGETABLE( (VAddr>>21)<<9 ), 0, 4096 );
77 // Check if this virtual address is already mapped
78 if( PAGETABLE(VAddr >> 12) & 1 )
81 PAGETABLE(VAddr >> 12) = PAddr | 3;
87 * \brief Removed a mapped page
89 void MM_Unmap(tVAddr VAddr)
92 if( !(PAGEMAPLVL4(VAddr >> 39) & 1) ) return ;
94 if( !(PAGEDIRPTR(VAddr >> 30) & 1) ) return ;
96 if( !(PAGEDIR(VAddr >> 21) & 1) ) return ;
98 PAGETABLE(VAddr >> 12) = 0;
102 * \brief Allocate a block of memory at the specified virtual address
104 tPAddr MM_Allocate(tVAddr VAddr)
108 ret = MM_AllocPhys();
111 if( !MM_Map(VAddr, ret) )
120 void MM_Deallocate(tVAddr VAddr)
124 phys = MM_GetPhysAddr(VAddr);
133 * \brief Get the physical address of a virtual location
135 tPAddr MM_GetPhysAddr(tVAddr Addr)
137 if( !(PAGEMAPLVL4(Addr >> 39) & 1) )
139 if( !(PAGEDIRPTR(Addr >> 30) & 1) )
141 if( !(PAGEDIR(Addr >> 21) & 1) )
143 if( !(PAGETABLE(Addr >> 12) & 1) )
146 return (PAGETABLE(Addr >> 12) & ~0xFFF) | (Addr & 0xFFF);
150 * \brief Sets the flags on a page
152 void MM_SetFlags(tVAddr VAddr, Uint Flags, Uint Mask)
157 if( !(PAGEMAPLVL4(VAddr >> 39) & 1) )
159 if( !(PAGEDIRPTR(VAddr >> 30) & 1) )
161 if( !(PAGEDIR(VAddr >> 21) & 1) )
163 if( !(PAGETABLE(VAddr >> 12) & 1) )
167 ent = &PAGETABLE(VAddr >> 12);
170 if( Mask & MM_PFLAG_RO )
172 if( Flags & MM_PFLAG_RO ) {
181 if( Mask & MM_PFLAG_KERNEL )
183 if( Flags & MM_PFLAG_KERNEL ) {
192 if( Mask & MM_PFLAG_COW )
194 if( Flags & MM_PFLAG_COW ) {
205 if( Mask & MM_PFLAG_EXEC )
207 if( Flags & MM_PFLAG_EXEC ) {
217 * \brief Get the flags applied to a page
219 Uint MM_GetFlags(tVAddr VAddr)
225 if( !(PAGEMAPLVL4(VAddr >> 39) & 1) )
227 if( !(PAGEDIRPTR(VAddr >> 30) & 1) )
229 if( !(PAGEDIR(VAddr >> 21) & 1) )
231 if( !(PAGETABLE(VAddr >> 12) & 1) )
235 ent = &PAGETABLE(VAddr >> 12);
238 if( !(*ent & PF_WRITE) ) ret |= MM_PFLAG_RO;
240 if( !(*ent & PF_USER) ) ret |= MM_PFLAG_KERNEL;
242 if( *ent & PF_COW ) ret |= MM_PFLAG_COW;
244 if( !(*ent & PF_NX) ) ret |= MM_PFLAG_EXEC;
249 // --- Hardware Mappings ---
251 * \brief Map a range of hardware pages
253 tVAddr MM_MapHWPages(tPAddr PAddr, Uint Number)
255 Log_KernelPanic("MM", "TODO: Implement MM_MapHWPages");
260 * \brief Free a range of hardware pages
262 void MM_UnmapHWPages(tVAddr VAddr, Uint Number)
264 Log_KernelPanic("MM", "TODO: Implement MM_UnmapHWPages");
267 // --- Tempory Mappings ---
268 tVAddr MM_MapTemp(tPAddr PAddr)
270 Log_KernelPanic("MM", "TODO: Implement MM_MapTemp");
274 void MM_FreeTemp(tVAddr VAddr)
276 Log_KernelPanic("MM", "TODO: Implement MM_FreeTemp");
281 // --- Address Space Clone --
282 tPAddr MM_Clone(void)
286 // #1 Create a copy of the PML4
287 ret = MM_AllocPhys();
290 // #2 Alter the fractal pointer
291 // #3 Set Copy-On-Write to all user pages
296 void MM_ClearUser(void)
299 // #1 Traverse the structure < 2^47, Deref'ing all pages
300 // #2 Free tables/dirs/pdps once they have been cleared
302 for( addr = 0; addr < 0x800000000000; )
304 if( PAGEMAPLVL4(addr >> PML4_SHIFT) & 1 )
306 if( PAGEDIRPTR(addr >> PDP_SHIFT) & 1 )
308 if( PAGEDIR(addr >> PDIR_SHIFT) & 1 )
311 if( PAGETABLE(addr >> PTAB_SHIFT) & 1 ) {
312 MM_DerefPhys( PAGETABLE(addr >> PTAB_SHIFT) & PADDR_MASK );
313 PAGETABLE(addr >> PTAB_SHIFT) = 0;
315 addr += 1 << PTAB_SHIFT;
316 // Dereference the PDIR Entry
317 if( (addr + (1 << PTAB_SHIFT)) >> PDIR_SHIFT != (addr >> PDIR_SHIFT) ) {
318 MM_DerefPhys( PAGEMAPLVL4(addr >> PDIR_SHIFT) & PADDR_MASK );
319 PAGEDIR(addr >> PDIR_SHIFT) = 0;
323 addr += 1 << PDIR_SHIFT;
326 // Dereference the PDP Entry
327 if( (addr + (1 << PDIR_SHIFT)) >> PDP_SHIFT != (addr >> PDP_SHIFT) ) {
328 MM_DerefPhys( PAGEMAPLVL4(addr >> PDP_SHIFT) & PADDR_MASK );
329 PAGEDIRPTR(addr >> PDP_SHIFT) = 0;
333 addr += 1 << PDP_SHIFT;
336 // Dereference the PML4 Entry
337 if( (addr + (1 << PDP_SHIFT)) >> PML4_SHIFT != (addr >> PML4_SHIFT) ) {
338 MM_DerefPhys( PAGEMAPLVL4(addr >> PML4_SHIFT) & PADDR_MASK );
339 PAGEMAPLVL4(addr >> PML4_SHIFT) = 0;
343 addr += (tVAddr)1 << PML4_SHIFT;
349 tVAddr MM_NewWorkerStack(void)
354 tVAddr MM_NewKStack(void)