X-Git-Url: http://git.joshuawise.com/netwatch.git/blobdiff_plain/923ea2c2cd9df7f02ddcfd8c543f63b76be44660..cdde55f54a0880bde5694fcdea8e386ada0cd5ce:/aseg-paging/pagingstub.c?ds=inline diff --git a/aseg-paging/pagingstub.c b/aseg-paging/pagingstub.c index 161dc1f..782bf0f 100644 --- a/aseg-paging/pagingstub.c +++ b/aseg-paging/pagingstub.c @@ -23,14 +23,26 @@ void ps_switch_stack (void (*call)(), int stack); asm volatile("mov %%cr0, %0" : "=r" (_temp__)); \ _temp__; \ }) - - #define set_cr3(value) \ { \ register unsigned int _temp__ = (value); \ asm volatile("mov %0, %%cr3" : : "r" (_temp__)); \ } + +#define get_cr4() \ + ({ \ + register unsigned int _temp__; \ + asm volatile("mov %%cr4, %0" : "=r" (_temp__)); \ + _temp__; \ + }) +#define set_cr4(value) \ + { \ + register unsigned int _temp__ = (value); \ + asm volatile("mov %0, %%cr4" : : "r" (_temp__)); \ + } + #define CR0_PG 0x80000000 +#define CR4_PSE 0x00000010 #define MAP_FLAGS (PTE_PRESENT | PTE_READ_WRITE) @@ -40,6 +52,8 @@ static unsigned long *pd; extern int _bss, _bssend, _end; +static unsigned long curmapped = 0xFFFFFFFF; + unsigned long v2p(void *virt) { unsigned long _virt = (unsigned long)virt; @@ -47,12 +61,19 @@ unsigned long v2p(void *virt) if (!paging_enb) return _virt; - if (_virt >= 0xA0000 && _virt < 0xC0000) - return _virt; - if (_virt >= 0x200000 && _virt < 0x300000) - return _virt - 0x200000 + /* XXX */ 0x1FF82000; - outputf("WARNING: v2p(%08x)", _virt); - return 0xFFFFFFFF; + unsigned long pde = ((unsigned long *)p2v((unsigned long)pd))[PDE_FOR(_virt)]; + unsigned long pte; + + if (!(pde & PTE_PRESENT)) + return 0xFFFFFFFF; + + if (pde & PDE_PAGE_SIZE) + return ADDR_12_MASK(pde) + (_virt & 0x3FFFFF); + + pte = ((unsigned long *)p2v(ADDR_12_MASK(pde)))[PTE_FOR(_virt)]; + if (!(pte & PTE_PRESENT)) + return 0xFFFFFFFF; + return (pte & ~0xFFF) + (_virt & 0xFFF); } void *p2v(unsigned long phys) @@ -62,14 +83,21 @@ void *p2v(unsigned long phys) if (phys >= 0xA0000 && phys < 0xC0000) return (void*)phys; - if (phys >= 0x1FF80000 && phys < 0x20000000) + if (phys >= 0x1FF82000 && phys < 0x20000000) return (void*)(phys - 0x1FF82000 + 0x200000); - outputf("WARNING: p2v(%08x)", phys); - return (void *)0xFFFFFFFF; + if (phys >= 0x1FF80000 && phys < 0x1FF82000) + return (void*)(phys - 0x1FF80000 + 0x1F0000); + + if ((phys & ~0xFFF) != curmapped) /* If it's not mapped, map it in. */ + { + curmapped = phys & ~0xFFF; + addmap(0x4000, curmapped); + asm volatile("invlpg 0x4000"); + } + return (void*)(0x4000 + (phys & 0xFFF)); } - -inline int pt_addmap(unsigned long *pd, unsigned long vaddr, unsigned long paddr) +int addmap(unsigned long vaddr, unsigned long paddr) { unsigned long pde = ((unsigned long *)p2v((unsigned long)pd))[PDE_FOR(vaddr)]; unsigned long *pt; @@ -83,13 +111,37 @@ inline int pt_addmap(unsigned long *pd, unsigned long vaddr, unsigned long paddr return 0; } -static void * pt_setup(int tseg_start, int tseg_size) { +int addmap_4m(unsigned long vaddr, unsigned long paddr) +{ + /* PDE_PAGE_SIZE = (1 << 7) */ + ((unsigned long *)p2v((unsigned long)pd))[PDE_FOR(vaddr)] = + paddr | PDE_PRESENT | PDE_READ_WRITE | PDE_PAGE_SIZE; + + return 0; +} + +void *demap(unsigned long client_pd, unsigned long vaddr) +{ + unsigned long pde = ((unsigned long *)p2v(client_pd))[PDE_FOR(vaddr)]; + unsigned long pte; + + if (!(pde & PTE_PRESENT)) + return (void*)0x0; + pte = ((unsigned long *)p2v(ADDR_12_MASK(pde)))[PTE_FOR(vaddr)]; + if (!(pte & PTE_PRESENT)) + return (void*)0x0; + return p2v((pte & ~0xFFF) + (vaddr & 0xFFF)); +} + +static void pt_setup(int tseg_start, int tseg_size) { int i; /* The page directory and page table live at TSEG and TSEG + 0x1000, * respectively. */ unsigned long *pagedirectory = (unsigned long *) tseg_start; unsigned long *pagetable = (unsigned long *) (tseg_start + 0x1000); + + pd = pagedirectory; /* Clear out the page directory except for one entry pointing to the * page table, and clear the page table entirely. */ @@ -102,18 +154,20 @@ static void * pt_setup(int tseg_start, int tseg_size) { /* Map 0x0A0000:0x0BFFFF to itself. */ for (i = 0; i < 32; i++) - pt_addmap(pagedirectory, 0xA0000 + i * 0x1000, 0xA0000 + i * 0x1000); + addmap(0xA0000 + i * 0x1000, 0xA0000 + i * 0x1000); - /* Map 0x200000:0x300000 to TSEG */ + /* Map 0x200000:0x300000 to TSEG data */ for (i = 0; i < 256; i++) - pt_addmap(pagedirectory, 0x200000 + i * 0x1000, tseg_start + 0x2000 + i * 0x1000); + addmap(0x200000 + i * 0x1000, tseg_start + (i + 2) * 0x1000); /* Map 0x300000:0x400000 to 0x200000, so we can copy our code out of * RAM the first time around */ for (i = 0; i < 256; i++) - pt_addmap(pagedirectory, 0x300000 + i * 0x1000, 0x200000 + i * 0x1000); + addmap(0x300000 + i * 0x1000, 0x200000 + i * 0x1000); - return pagedirectory; + /* Map 0x1F0000:0x1F2000 to TSEG paging info */ + for (i = 0; i < 2; i++) + addmap(0x1F0000 + i * 0x1000, tseg_start + i * 0x1000); } void c_entry(void) @@ -122,11 +176,12 @@ void c_entry(void) outb(0x80, 0x01); if (!initialized) - pd = pt_setup(0x1FF80000, 0x80000); + pt_setup(0x1FF80000, 0x80000); outb(0x80, 0x02); /* Enable paging. */ set_cr3((unsigned long)pd); + set_cr4(get_cr4() | CR4_PSE); /* ITT, we 4MByte page. */ set_cr0(get_cr0() | CR0_PG); outb(0x80, 0x03); paging_enb = 1;