/*===========================================================================*
* pt_ptmap *
*===========================================================================*/
PUBLIC int pt_ptmap(struct vmproc *src_vmp, struct vmproc *dst_vmp)
{
/* Transfer mappings to page dir and page tables from source process and
* destination process. Make sure all the mappings are above the stack, not
* to corrupt valid mappings in the data segment of the destination process.
*/
int pde, r;
phys_bytes physaddr;
vir_bytes viraddr;
pt_t *pt;
assert(src_vmp->vm_stacktop == dst_vmp->vm_stacktop);
pt = &src_vmp->vm_pt;
#if LU_DEBUG
printf("VM: pt_ptmap: src = %d, dst = %d\n",
src_vmp->vm_endpoint, dst_vmp->vm_endpoint);
#endif
/* Transfer mapping to the page directory. */
assert((vir_bytes) pt->pt_dir >= src_vmp->vm_stacktop);
viraddr = arch_vir2map(src_vmp, (vir_bytes) pt->pt_dir);
physaddr = pt->pt_dir_phys & I386_VM_ADDR_MASK;
if((r=pt_writemap(dst_vmp, &dst_vmp->vm_pt, viraddr, physaddr, I386_PAGE_SIZE,
I386_VM_PRESENT | I386_VM_USER | I386_VM_WRITE,
WMF_OVERWRITE)) != OK) {
return r;
}
#if LU_DEBUG
printf("VM: pt_ptmap: transferred mapping to page dir: 0x%08x (0x%08x)\n",
viraddr, physaddr);
#endif
/* Scan all non-reserved page-directory entries. */
for(pde=proc_pde; pde < I386_VM_DIR_ENTRIES; pde++) {
if(!(pt->pt_dir[pde] & I386_VM_PRESENT)) {
continue;
}
/* Transfer mapping to the page table. */
assert((vir_bytes) pt->pt_pt[pde] >= src_vmp->vm_stacktop);
viraddr = arch_vir2map(src_vmp, (vir_bytes) pt->pt_pt[pde]);
physaddr = pt->pt_dir[pde] & I386_VM_ADDR_MASK;
if((r=pt_writemap(dst_vmp, &dst_vmp->vm_pt, viraddr, physaddr, I386_PAGE_SIZE,
I386_VM_PRESENT | I386_VM_USER | I386_VM_WRITE,
WMF_OVERWRITE)) != OK) {
return r;
}
}
#if LU_DEBUG
printf("VM: pt_ptmap: transferred mappings to page tables, pde range %d - %d\n",
proc_pde, I386_VM_DIR_ENTRIES - 1);
#endif
return OK;
}
/*===========================================================================*
* vm_pagelock *
*===========================================================================*/
void vm_pagelock(void *vir, int lockflag)
{
/* Mark a page allocated by vm_allocpage() unwritable, i.e. only for VM. */
vir_bytes m = (vir_bytes) vir;
int r;
u32_t flags = ARCH_VM_PTE_PRESENT | ARCH_VM_PTE_USER;
pt_t *pt;
pt = &vmprocess->vm_pt;
assert(!(m % VM_PAGE_SIZE));
if(!lockflag)
flags |= ARCH_VM_PTE_RW;
#if defined(__arm__)
else
flags |= ARCH_VM_PTE_RO;
flags |= ARM_VM_PTE_WT ;
#endif
/* Update flags. */
if((r=pt_writemap(vmprocess, pt, m, 0, VM_PAGE_SIZE,
flags, WMF_OVERWRITE | WMF_WRITEFLAGSONLY)) != OK) {
panic("vm_lockpage: pt_writemap failed");
}
if((r=sys_vmctl(SELF, VMCTL_FLUSHTLB, 0)) != OK) {
panic("VMCTL_FLUSHTLB failed: %d", r);
}
return;
}
void *vm_mappages(phys_bytes p, int pages)
{
vir_bytes loc;
int r;
pt_t *pt = &vmprocess->vm_pt;
/* Where in our virtual address space can we put it? */
loc = findhole(pages);
if(loc == NO_MEM) {
printf("vm_mappages: findhole failed\n");
return NULL;
}
/* Map this page into our address space. */
if((r=pt_writemap(vmprocess, pt, loc, p, VM_PAGE_SIZE*pages,
ARCH_VM_PTE_PRESENT | ARCH_VM_PTE_USER | ARCH_VM_PTE_RW
#if defined(__arm__)
| ARM_VM_PTE_WT
#endif
, 0)) != OK) {
printf("vm_mappages writemap failed\n");
return NULL;
}
if((r=sys_vmctl(SELF, VMCTL_FLUSHTLB, 0)) != OK) {
panic("VMCTL_FLUSHTLB failed: %d", r);
}
assert(loc);
return (void *) loc;
}
/*===========================================================================*
* vm_freepages *
*===========================================================================*/
void vm_freepages(vir_bytes vir, int pages)
{
assert(!(vir % VM_PAGE_SIZE));
if(is_staticaddr(vir)) {
printf("VM: not freeing static page\n");
return;
}
if(pt_writemap(vmprocess, &vmprocess->vm_pt, vir,
MAP_NONE, pages*VM_PAGE_SIZE, 0,
WMF_OVERWRITE | WMF_FREE) != OK)
panic("vm_freepages: pt_writemap failed");
vm_self_pages--;
#if SANITYCHECKS
/* If SANITYCHECKS are on, flush tlb so accessing freed pages is
* always trapped, also if not in tlb.
*/
if((sys_vmctl(SELF, VMCTL_FLUSHTLB, 0)) != OK) {
panic("VMCTL_FLUSHTLB failed");
}
#endif
}
int _brk(void *addr)
{
vir_bytes target = roundup((vir_bytes)addr, VM_PAGE_SIZE), v;
extern char _end;
extern char *_brksize;
static vir_bytes prevbrk = (vir_bytes) &_end;
struct vmproc *vmprocess = &vmproc[VM_PROC_NR];
for(v = roundup(prevbrk, VM_PAGE_SIZE); v < target;
v += VM_PAGE_SIZE) {
phys_bytes mem, newpage = alloc_mem(1, 0);
if(newpage == NO_MEM) return -1;
mem = CLICK2ABS(newpage);
if(pt_writemap(vmprocess, &vmprocess->vm_pt,
v, mem, VM_PAGE_SIZE,
ARCH_VM_PTE_PRESENT
| ARCH_VM_PTE_USER
| ARCH_VM_PTE_RW
#if defined(__arm__)
| ARM_VM_PTE_WB
#endif
, 0) != OK) {
free_mem(newpage, 1);
return -1;
}
prevbrk = v + VM_PAGE_SIZE;
}
_brksize = (char *) addr;
if(sys_vmctl(SELF, VMCTL_FLUSHTLB, 0) != OK)
panic("flushtlb failed");
return 0;
}
/*===========================================================================*
* vm_pagelock *
*===========================================================================*/
PUBLIC void vm_pagelock(void *vir, int lockflag)
{
/* Mark a page allocated by vm_allocpage() unwritable, i.e. only for VM. */
vir_bytes m;
int r;
u32_t flags = I386_VM_PRESENT | I386_VM_USER;
pt_t *pt;
pt = &vmprocess->vm_pt;
m = arch_vir2map(vmprocess, (vir_bytes) vir);
assert(!(m % I386_PAGE_SIZE));
if(!lockflag)
flags |= I386_VM_WRITE;
/* Update flags. */
if((r=pt_writemap(vmprocess, pt, m, 0, I386_PAGE_SIZE,
flags, WMF_OVERWRITE | WMF_WRITEFLAGSONLY)) != OK) {
panic("vm_lockpage: pt_writemap failed");
}
if((r=sys_vmctl(SELF, VMCTL_FLUSHTLB, 0)) != OK) {
panic("VMCTL_FLUSHTLB failed: %d", r);
}
return;
}
/*===========================================================================*
* vm_freepages *
*===========================================================================*/
PRIVATE void vm_freepages(vir_bytes vir, vir_bytes phys, int pages, int reason)
{
vm_assert(reason >= 0 && reason < VMP_CATEGORIES);
if(vir >= vmp->vm_stacktop) {
vm_assert(!(vir % I386_PAGE_SIZE));
vm_assert(!(phys % I386_PAGE_SIZE));
FREE_MEM(ABS2CLICK(phys), pages);
if(pt_writemap(&vmp->vm_pt, arch_vir2map(vmp, vir),
MAP_NONE, pages*I386_PAGE_SIZE, 0, WMF_OVERWRITE) != OK)
vm_panic("vm_freepages: pt_writemap failed",
NO_NUM);
} else {
printf("VM: vm_freepages not freeing VM heap pages (%d)\n",
pages);
}
}
/*===========================================================================*
* munmap_lin (used for overrides for VM) *
*===========================================================================*/
PRIVATE int munmap_lin(vir_bytes addr, size_t len)
{
if(addr % VM_PAGE_SIZE) {
printf("munmap_lin: offset not page aligned\n");
return EFAULT;
}
if(len % VM_PAGE_SIZE) {
printf("munmap_lin: len not page aligned\n");
return EFAULT;
}
if(pt_writemap(NULL, &vmproc[VM_PROC_NR].vm_pt, addr, MAP_NONE, len, 0,
WMF_OVERWRITE | WMF_FREE) != OK) {
printf("munmap_lin: pt_writemap failed\n");
return EFAULT;
}
return OK;
}
/*===========================================================================*
* pt_mapkernel *
*===========================================================================*/
PUBLIC int pt_mapkernel(pt_t *pt)
{
int r, i;
/* Any i386 page table needs to map in the kernel address space. */
assert(vmproc[VMP_SYSTEM].vm_flags & VMF_INUSE);
if(bigpage_ok) {
int pde;
for(pde = 0; pde <= id_map_high_pde; pde++) {
phys_bytes addr;
addr = pde * I386_BIG_PAGE_SIZE;
assert((addr & I386_VM_ADDR_MASK) == addr);
pt->pt_dir[pde] = addr | I386_VM_PRESENT |
I386_VM_BIGPAGE | I386_VM_USER |
I386_VM_WRITE | global_bit;
}
} else {
panic("VM: pt_mapkernel: no bigpage");
}
if(pagedir_pde >= 0) {
/* Kernel also wants to know about all page directories. */
pt->pt_dir[pagedir_pde] = pagedir_pde_val;
}
for(i = 0; i < kernmappings; i++) {
if(pt_writemap(NULL, pt,
kern_mappings[i].lin_addr,
kern_mappings[i].phys_addr,
kern_mappings[i].len,
kern_mappings[i].flags, 0) != OK) {
panic("pt_mapkernel: pt_writemap failed");
}
}
return OK;
}
/*===========================================================================*
* vm_freepages *
*===========================================================================*/
PRIVATE void vm_freepages(vir_bytes vir, vir_bytes phys, int pages, int reason)
{
assert(reason >= 0 && reason < VMP_CATEGORIES);
if(vir >= vmprocess->vm_stacktop) {
assert(!(vir % I386_PAGE_SIZE));
assert(!(phys % I386_PAGE_SIZE));
free_mem(ABS2CLICK(phys), pages);
if(pt_writemap(vmprocess, &vmprocess->vm_pt, arch_vir2map(vmprocess, vir),
MAP_NONE, pages*I386_PAGE_SIZE, 0, WMF_OVERWRITE) != OK)
panic("vm_freepages: pt_writemap failed");
} else {
printf("VM: vm_freepages not freeing VM heap pages (%d)\n",
pages);
}
#if SANITYCHECKS
/* If SANITYCHECKS are on, flush tlb so accessing freed pages is
* always trapped, also if not in tlb.
*/
if((sys_vmctl(SELF, VMCTL_FLUSHTLB, 0)) != OK) {
panic("VMCTL_FLUSHTLB failed");
}
#endif
}
/*===========================================================================*
* pt_ptmap *
*===========================================================================*/
int pt_ptmap(struct vmproc *src_vmp, struct vmproc *dst_vmp)
{
/* Transfer mappings to page dir and page tables from source process and
* destination process. Make sure all the mappings are above the stack, not
* to corrupt valid mappings in the data segment of the destination process.
*/
int pde, r;
phys_bytes physaddr;
vir_bytes viraddr;
pt_t *pt;
pt = &src_vmp->vm_pt;
#if LU_DEBUG
printf("VM: pt_ptmap: src = %d, dst = %d\n",
src_vmp->vm_endpoint, dst_vmp->vm_endpoint);
#endif
/* Transfer mapping to the page directory. */
viraddr = (vir_bytes) pt->pt_dir;
physaddr = pt->pt_dir_phys & ARCH_VM_ADDR_MASK;
#if defined(__i386__)
if((r=pt_writemap(dst_vmp, &dst_vmp->vm_pt, viraddr, physaddr, VM_PAGE_SIZE,
ARCH_VM_PTE_PRESENT | ARCH_VM_PTE_USER | ARCH_VM_PTE_RW,
#elif defined(__arm__)
if((r=pt_writemap(dst_vmp, &dst_vmp->vm_pt, viraddr, physaddr, ARCH_PAGEDIR_SIZE,
ARCH_VM_PTE_PRESENT | ARCH_VM_PTE_USER |
ARM_VM_PTE_WT ,
#endif
WMF_OVERWRITE)) != OK) {
return r;
}
#if LU_DEBUG
printf("VM: pt_ptmap: transferred mapping to page dir: 0x%08x (0x%08x)\n",
viraddr, physaddr);
#endif
/* Scan all non-reserved page-directory entries. */
for(pde=0; pde < ARCH_VM_DIR_ENTRIES; pde++) {
if(!(pt->pt_dir[pde] & ARCH_VM_PDE_PRESENT)) {
continue;
}
/* Transfer mapping to the page table. */
viraddr = (vir_bytes) pt->pt_pt[pde];
#if defined(__i386__)
physaddr = pt->pt_dir[pde] & ARCH_VM_ADDR_MASK;
#elif defined(__arm__)
physaddr = pt->pt_dir[pde] & ARCH_VM_PDE_MASK;
#endif
if((r=pt_writemap(dst_vmp, &dst_vmp->vm_pt, viraddr, physaddr, VM_PAGE_SIZE,
ARCH_VM_PTE_PRESENT | ARCH_VM_PTE_USER | ARCH_VM_PTE_RW
#ifdef __arm__
| ARM_VM_PTE_WT
#endif
,
WMF_OVERWRITE)) != OK) {
return r;
}
}
return OK;
}
/*===========================================================================*
* pt_mapkernel *
*===========================================================================*/
int pt_mapkernel(pt_t *pt)
{
int i;
int kern_pde = kern_start_pde;
phys_bytes addr, mapped = 0;
/* Any page table needs to map in the kernel address space. */
assert(bigpage_ok);
assert(kern_pde >= 0);
/* pt_init() has made sure this is ok. */
addr = kern_mb_mod->mod_start;
/* Actually mapping in kernel */
while(mapped < kern_size) {
#if defined(__i386__)
pt->pt_dir[kern_pde] = addr | ARCH_VM_PDE_PRESENT |
ARCH_VM_BIGPAGE | ARCH_VM_PTE_RW | global_bit;
#elif defined(__arm__)
pt->pt_dir[kern_pde] = (addr & ARCH_VM_PDE_MASK)
| ARM_VM_SECTION
| ARM_VM_SECTION_DOMAIN
| ARM_VM_SECTION_WT
| ARM_VM_SECTION_SUPER;
#endif
kern_pde++;
mapped += ARCH_BIG_PAGE_SIZE;
addr += ARCH_BIG_PAGE_SIZE;
}
/* Kernel also wants to know about all page directories. */
{
int pd;
for(pd = 0; pd < MAX_PAGEDIR_PDES; pd++) {
struct pdm *pdm = &pagedir_mappings[pd];
assert(pdm->pdeno > 0);
assert(pdm->pdeno > kern_pde);
pt->pt_dir[pdm->pdeno] = pdm->val;
}
}
/* Kernel also wants various mappings of its own. */
for(i = 0; i < kernmappings; i++) {
int r;
#if defined(__arm__)
#ifdef DM37XX
//FIXME this special case will be removed once we have non 1:1 mapping
#define XXX 0x48000000
#endif
#ifdef AM335X
#define XXX 0x44000000
#endif
if(kern_mappings[i].phys_addr == XXX) {
addr = kern_mappings[i].phys_addr;
assert(!(kern_mappings[i].len % ARCH_BIG_PAGE_SIZE));
for(mapped = 0; mapped < kern_mappings[i].len;
mapped += ARCH_BIG_PAGE_SIZE) {
int map_pde = addr / ARCH_BIG_PAGE_SIZE;
assert(!(addr % ARCH_BIG_PAGE_SIZE));
assert(addr == (addr & ARCH_VM_PDE_MASK));
assert(!pt->pt_dir[map_pde]);
pt->pt_dir[map_pde] = addr |
ARM_VM_SECTION | ARM_VM_SECTION_DOMAIN |
ARM_VM_SECTION_DEVICE |
ARM_VM_SECTION_SUPER;
addr += ARCH_BIG_PAGE_SIZE;
}
continue;
}
#endif
if((r=pt_writemap(NULL, pt,
kern_mappings[i].vir_addr,
kern_mappings[i].phys_addr,
kern_mappings[i].len,
kern_mappings[i].flags, 0)) != OK) {
return r;
}
}
return OK;
}
/*===========================================================================*
* pt_init *
*===========================================================================*/
PUBLIC void pt_init(phys_bytes usedlimit)
{
/* By default, the kernel gives us a data segment with pre-allocated
* memory that then can't grow. We want to be able to allocate memory
* dynamically, however. So here we copy the part of the page table
* that's ours, so we get a private page table. Then we increase the
* hardware segment size so we can allocate memory above our stack.
*/
pt_t *newpt;
int s, r;
vir_bytes v;
phys_bytes lo, hi;
vir_bytes extra_clicks;
u32_t moveup = 0;
int global_bit_ok = 0;
int free_pde;
int p;
struct vm_ep_data ep_data;
vir_bytes sparepages_mem;
phys_bytes sparepages_ph;
vir_bytes ptr;
/* Shorthand. */
newpt = &vmprocess->vm_pt;
/* Get ourselves spare pages. */
ptr = (vir_bytes) static_sparepages;
ptr += I386_PAGE_SIZE - (ptr % I386_PAGE_SIZE);
if(!(sparepages_mem = ptr))
panic("pt_init: aalloc for spare failed");
if((r=sys_umap(SELF, VM_D, (vir_bytes) sparepages_mem,
I386_PAGE_SIZE*SPAREPAGES, &sparepages_ph)) != OK)
panic("pt_init: sys_umap failed: %d", r);
missing_spares = 0;
assert(STATIC_SPAREPAGES < SPAREPAGES);
for(s = 0; s < SPAREPAGES; s++) {
if(s >= STATIC_SPAREPAGES) {
sparepages[s].page = NULL;
missing_spares++;
continue;
}
sparepages[s].page = (void *) (sparepages_mem + s*I386_PAGE_SIZE);
sparepages[s].phys = sparepages_ph + s*I386_PAGE_SIZE;
}
/* global bit and 4MB pages available? */
global_bit_ok = _cpufeature(_CPUF_I386_PGE);
bigpage_ok = _cpufeature(_CPUF_I386_PSE);
/* Set bit for PTE's and PDE's if available. */
if(global_bit_ok)
global_bit = I386_VM_GLOBAL;
/* The kernel and boot time processes need an identity mapping.
* We use full PDE's for this without separate page tables.
* Figure out which pde we can start using for other purposes.
*/
id_map_high_pde = usedlimit / I386_BIG_PAGE_SIZE;
/* We have to make mappings up till here. */
free_pde = id_map_high_pde+1;
/* Initial (current) range of our virtual address space. */
lo = CLICK2ABS(vmprocess->vm_arch.vm_seg[T].mem_phys);
hi = CLICK2ABS(vmprocess->vm_arch.vm_seg[S].mem_phys +
vmprocess->vm_arch.vm_seg[S].mem_len);
assert(!(lo % I386_PAGE_SIZE));
assert(!(hi % I386_PAGE_SIZE));
if(lo < VM_PROCSTART) {
moveup = VM_PROCSTART - lo;
assert(!(VM_PROCSTART % I386_PAGE_SIZE));
assert(!(lo % I386_PAGE_SIZE));
assert(!(moveup % I386_PAGE_SIZE));
}
/* Make new page table for ourselves, partly copied
* from the current one.
*/
if(pt_new(newpt) != OK)
panic("pt_init: pt_new failed");
/* Set up mappings for VM process. */
for(v = lo; v < hi; v += I386_PAGE_SIZE) {
phys_bytes addr;
u32_t flags;
/* We have to write the new position in the PT,
* so we can move our segments.
*/
if(pt_writemap(vmprocess, newpt, v+moveup, v, I386_PAGE_SIZE,
I386_VM_PRESENT|I386_VM_WRITE|I386_VM_USER, 0) != OK)
panic("pt_init: pt_writemap failed");
}
/* Move segments up too. */
vmprocess->vm_arch.vm_seg[T].mem_phys += ABS2CLICK(moveup);
vmprocess->vm_arch.vm_seg[D].mem_phys += ABS2CLICK(moveup);
vmprocess->vm_arch.vm_seg[S].mem_phys += ABS2CLICK(moveup);
/* Allocate us a page table in which to remember page directory
* pointers.
*/
if(!(page_directories = vm_allocpage(&page_directories_phys,
VMP_PAGETABLE)))
panic("no virt addr for vm mappings");
memset(page_directories, 0, I386_PAGE_SIZE);
/* Increase our hardware data segment to create virtual address
* space above our stack. We want to increase it to VM_DATATOP,
* like regular processes have.
*/
extra_clicks = ABS2CLICK(VM_DATATOP - hi);
vmprocess->vm_arch.vm_seg[S].mem_len += extra_clicks;
/* We pretend to the kernel we have a huge stack segment to
* increase our data segment.
*/
vmprocess->vm_arch.vm_data_top =
(vmprocess->vm_arch.vm_seg[S].mem_vir +
vmprocess->vm_arch.vm_seg[S].mem_len) << CLICK_SHIFT;
/* Where our free virtual address space starts.
* This is only a hint to the VM system.
*/
newpt->pt_virtop = 0;
/* Let other functions know VM now has a private page table. */
vmprocess->vm_flags |= VMF_HASPT;
/* Now reserve another pde for kernel's own mappings. */
{
int kernmap_pde;
phys_bytes addr, len;
int flags, index = 0;
u32_t offset = 0;
kernmap_pde = free_pde++;
offset = kernmap_pde * I386_BIG_PAGE_SIZE;
while(sys_vmctl_get_mapping(index, &addr, &len,
&flags) == OK) {
vir_bytes vir;
if(index >= MAX_KERNMAPPINGS)
panic("VM: too many kernel mappings: %d", index);
kern_mappings[index].phys_addr = addr;
kern_mappings[index].len = len;
kern_mappings[index].flags = flags;
kern_mappings[index].lin_addr = offset;
kern_mappings[index].flags =
I386_VM_PRESENT | I386_VM_USER | I386_VM_WRITE |
global_bit;
if(flags & VMMF_UNCACHED)
kern_mappings[index].flags |= PTF_NOCACHE;
if(addr % I386_PAGE_SIZE)
panic("VM: addr unaligned: %d", addr);
if(len % I386_PAGE_SIZE)
panic("VM: len unaligned: %d", len);
vir = arch_map2vir(&vmproc[VMP_SYSTEM], offset);
if(sys_vmctl_reply_mapping(index, vir) != OK)
panic("VM: reply failed");
offset += len;
index++;
kernmappings++;
}
}
/* Find a PDE below processes available for mapping in the
* page directories (readonly).
*/
pagedir_pde = free_pde++;
pagedir_pde_val = (page_directories_phys & I386_VM_ADDR_MASK) |
I386_VM_PRESENT | I386_VM_USER | I386_VM_WRITE;
/* Tell kernel about free pde's. */
while(free_pde*I386_BIG_PAGE_SIZE < VM_PROCSTART) {
if((r=sys_vmctl(SELF, VMCTL_I386_FREEPDE, free_pde++)) != OK) {
panic("VMCTL_I386_FREEPDE failed: %d", r);
}
}
/* first pde in use by process. */
proc_pde = free_pde;
/* Give our process the new, copied, private page table. */
pt_mapkernel(newpt); /* didn't know about vm_dir pages earlier */
pt_bind(newpt, vmprocess);
/* new segment limit for the kernel after paging is enabled */
ep_data.data_seg_limit = free_pde*I386_BIG_PAGE_SIZE;
/* the memory map which must be installed after paging is enabled */
ep_data.mem_map = vmprocess->vm_arch.vm_seg;
/* Now actually enable paging. */
if(sys_vmctl_enable_paging(&ep_data) != OK)
panic("pt_init: enable paging failed");
/* Back to reality - this is where the stack actually is. */
vmprocess->vm_arch.vm_seg[S].mem_len -= extra_clicks;
/* Pretend VM stack top is the same as any regular process, not to
* have discrepancies with new VM instances later on.
*/
vmprocess->vm_stacktop = VM_STACKTOP;
/* All OK. */
return;
}
/*===========================================================================*
* vm_allocpage *
*===========================================================================*/
PUBLIC void *vm_allocpage(phys_bytes *phys, int reason)
{
/* Allocate a page for use by VM itself. */
phys_bytes newpage;
vir_bytes loc;
pt_t *pt;
int r;
static int level = 0;
void *ret;
pt = &vmprocess->vm_pt;
assert(reason >= 0 && reason < VMP_CATEGORIES);
level++;
assert(level >= 1);
assert(level <= 2);
if(level > 1 || !(vmprocess->vm_flags & VMF_HASPT) || !meminit_done) {
int r;
void *s;
s=vm_getsparepage(phys);
level--;
if(!s) {
util_stacktrace();
printf("VM: warning: out of spare pages\n");
}
return s;
}
/* VM does have a pagetable, so get a page and map it in there.
* Where in our virtual address space can we put it?
*/
loc = findhole(pt, arch_vir2map(vmprocess, vmprocess->vm_stacktop),
vmprocess->vm_arch.vm_data_top);
if(loc == NO_MEM) {
level--;
printf("VM: vm_allocpage: findhole failed\n");
return NULL;
}
/* Allocate page of memory for use by VM. As VM
* is trusted, we don't have to pre-clear it.
*/
if((newpage = alloc_mem(CLICKSPERPAGE, 0)) == NO_MEM) {
level--;
printf("VM: vm_allocpage: alloc_mem failed\n");
return NULL;
}
*phys = CLICK2ABS(newpage);
/* Map this page into our address space. */
if((r=pt_writemap(vmprocess, pt, loc, *phys, I386_PAGE_SIZE,
I386_VM_PRESENT | I386_VM_USER | I386_VM_WRITE, 0)) != OK) {
free_mem(newpage, CLICKSPERPAGE);
printf("vm_allocpage writemap failed\n");
level--;
return NULL;
}
if((r=sys_vmctl(SELF, VMCTL_FLUSHTLB, 0)) != OK) {
panic("VMCTL_FLUSHTLB failed: %d", r);
}
level--;
/* Return user-space-ready pointer to it. */
ret = (void *) arch_map2vir(vmprocess, loc);
return ret;
}
/*===========================================================================*
* vm_allocpage *
*===========================================================================*/
void *vm_allocpages(phys_bytes *phys, int reason, int pages)
{
/* Allocate a page for use by VM itself. */
phys_bytes newpage;
vir_bytes loc;
pt_t *pt;
int r;
static int level = 0;
void *ret;
u32_t mem_flags = 0;
pt = &vmprocess->vm_pt;
assert(reason >= 0 && reason < VMP_CATEGORIES);
assert(pages > 0);
level++;
assert(level >= 1);
assert(level <= 2);
if((level > 1) || !pt_init_done) {
void *s;
if(pages == 1) s=vm_getsparepage(phys);
else if(pages == 4) s=vm_getsparepagedir(phys);
else panic("%d pages", pages);
level--;
if(!s) {
util_stacktrace();
printf("VM: warning: out of spare pages\n");
}
if(!is_staticaddr(s)) vm_self_pages++;
return s;
}
#if defined(__arm__)
if (reason == VMP_PAGEDIR) {
mem_flags |= PAF_ALIGN16K;
}
#endif
/* VM does have a pagetable, so get a page and map it in there.
* Where in our virtual address space can we put it?
*/
loc = findhole(pages);
if(loc == NO_MEM) {
level--;
printf("VM: vm_allocpage: findhole failed\n");
return NULL;
}
/* Allocate page of memory for use by VM. As VM
* is trusted, we don't have to pre-clear it.
*/
if((newpage = alloc_mem(pages, mem_flags)) == NO_MEM) {
level--;
printf("VM: vm_allocpage: alloc_mem failed\n");
return NULL;
}
*phys = CLICK2ABS(newpage);
/* Map this page into our address space. */
if((r=pt_writemap(vmprocess, pt, loc, *phys, VM_PAGE_SIZE*pages,
ARCH_VM_PTE_PRESENT | ARCH_VM_PTE_USER | ARCH_VM_PTE_RW
#if defined(__arm__)
| ARM_VM_PTE_WB | ARM_VM_PTE_SHAREABLE
#endif
, 0)) != OK) {
free_mem(newpage, pages);
printf("vm_allocpage writemap failed\n");
level--;
return NULL;
}
if((r=sys_vmctl(SELF, VMCTL_FLUSHTLB, 0)) != OK) {
panic("VMCTL_FLUSHTLB failed: %d", r);
}
level--;
/* Return user-space-ready pointer to it. */
ret = (void *) loc;
vm_self_pages++;
return ret;
}
/*===========================================================================*
* findhole *
*===========================================================================*/
static u32_t findhole(int pages)
{
/* Find a space in the virtual address space of VM. */
u32_t curv;
int pde = 0, try_restart;
static u32_t lastv = 0;
pt_t *pt = &vmprocess->vm_pt;
vir_bytes vmin, vmax;
#if defined(__arm__)
u32_t holev;
#endif
vmin = (vir_bytes) (&_end); /* marks end of VM BSS */
vmin += 1024*1024*1024; /* reserve 1GB virtual address space for VM heap */
vmin &= ARCH_VM_ADDR_MASK;
vmax = VM_STACKTOP;
/* Input sanity check. */
assert(vmin + VM_PAGE_SIZE >= vmin);
assert(vmax >= vmin + VM_PAGE_SIZE);
assert((vmin % VM_PAGE_SIZE) == 0);
assert((vmax % VM_PAGE_SIZE) == 0);
#if defined(__arm__)
assert(pages > 0);
#endif
#if SANITYCHECKS
curv = ((u32_t) random()) % ((vmax - vmin)/VM_PAGE_SIZE);
curv *= VM_PAGE_SIZE;
curv += vmin;
#else
curv = lastv;
if(curv < vmin || curv >= vmax)
curv = vmin;
#endif
try_restart = 1;
/* Start looking for a free page starting at vmin. */
while(curv < vmax) {
int pte;
#if defined(__arm__)
int i, nohole;
#endif
assert(curv >= vmin);
assert(curv < vmax);
#if defined(__i386__)
pde = I386_VM_PDE(curv);
pte = I386_VM_PTE(curv);
#elif defined(__arm__)
holev = curv; /* the candidate hole */
nohole = 0;
for (i = 0; i < pages && !nohole; ++i) {
if(curv >= vmax) {
break;
}
#endif
#if defined(__i386__)
if(!(pt->pt_dir[pde] & ARCH_VM_PDE_PRESENT) ||
!(pt->pt_pt[pde][pte] & ARCH_VM_PAGE_PRESENT)) {
#elif defined(__arm__)
pde = ARM_VM_PDE(curv);
pte = ARM_VM_PTE(curv);
/* if page present, no hole */
if((pt->pt_dir[pde] & ARCH_VM_PDE_PRESENT) &&
(pt->pt_pt[pde][pte] & ARCH_VM_PTE_PRESENT))
nohole = 1;
/* if not contiguous, no hole */
if (curv != holev + i * VM_PAGE_SIZE)
nohole = 1;
curv+=VM_PAGE_SIZE;
}
/* there's a large enough hole */
if (!nohole && i == pages) {
#endif
lastv = curv;
#if defined(__i386__)
return curv;
#elif defined(__arm__)
return holev;
#endif
}
#if defined(__i386__)
curv+=VM_PAGE_SIZE;
#elif defined(__arm__)
/* Reset curv */
#endif
if(curv >= vmax && try_restart) {
curv = vmin;
try_restart = 0;
}
}
printf("VM: out of virtual address space in vm\n");
return NO_MEM;
}
/*===========================================================================*
* vm_freepages *
*===========================================================================*/
void vm_freepages(vir_bytes vir, int pages)
{
assert(!(vir % VM_PAGE_SIZE));
if(is_staticaddr(vir)) {
printf("VM: not freeing static page\n");
return;
}
if(pt_writemap(vmprocess, &vmprocess->vm_pt, vir,
MAP_NONE, pages*VM_PAGE_SIZE, 0,
WMF_OVERWRITE | WMF_FREE) != OK)
panic("vm_freepages: pt_writemap failed");
vm_self_pages--;
#if SANITYCHECKS
/* If SANITYCHECKS are on, flush tlb so accessing freed pages is
* always trapped, also if not in tlb.
*/
if((sys_vmctl(SELF, VMCTL_FLUSHTLB, 0)) != OK) {
panic("VMCTL_FLUSHTLB failed");
}
#endif
}
