/*===========================================================================*
* 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 *
*===========================================================================*/
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;
}
/*===========================================================================*
* do_unmap_phys *
*===========================================================================*/
PUBLIC int do_unmap_phys(message *m)
{
int r, n;
struct vmproc *vmp;
endpoint_t target;
struct vir_region *region;
target = m->VMUP_EP;
if(target == SELF)
target = m->m_source;
if((r=vm_isokendpt(target, &n)) != OK)
return EINVAL;
vmp = &vmproc[n];
if(!(region = map_lookup(vmp,
arch_vir2map(vmp, (vir_bytes) m->VMUM_ADDR)))) {
return EINVAL;
}
if(!(region->flags & VR_DIRECT)) {
return EINVAL;
}
if(map_unmap_region(vmp, region, region->length) != OK) {
return EINVAL;
}
return OK;
}
/*===========================================================================*
* munmap (override for VM) *
*===========================================================================*/
PUBLIC int minix_munmap(void *addr, size_t len)
{
vir_bytes laddr;
if(!unmap_ok)
return ENOSYS;
laddr = (vir_bytes) arch_vir2map(&vmproc[VM_PROC_NR], (vir_bytes) addr);
return munmap_lin(laddr, len);
}
/*===========================================================================*
* do_mmap *
*===========================================================================*/
PUBLIC int do_mmap(message *m)
{
int r, n;
struct vmproc *vmp;
int mfflags = 0;
struct vir_region *vr = NULL;
if((r=vm_isokendpt(m->m_source, &n)) != OK) {
panic("do_mmap: message from strange source: %d", m->m_source);
}
vmp = &vmproc[n];
if(!(vmp->vm_flags & VMF_HASPT))
return ENXIO;
if(m->VMM_FD == -1 || (m->VMM_FLAGS & MAP_ANON)) {
int s;
vir_bytes v;
u32_t vrflags = VR_ANON | VR_WRITABLE;
size_t len = (vir_bytes) m->VMM_LEN;
if(m->VMM_FD != -1) {
return EINVAL;
}
/* Contiguous phys memory has to be preallocated. */
if((m->VMM_FLAGS & (MAP_CONTIG|MAP_PREALLOC)) == MAP_CONTIG) {
return EINVAL;
}
if(m->VMM_FLAGS & MAP_PREALLOC) mfflags |= MF_PREALLOC;
if(m->VMM_FLAGS & MAP_LOWER16M) vrflags |= VR_LOWER16MB;
if(m->VMM_FLAGS & MAP_LOWER1M) vrflags |= VR_LOWER1MB;
if(m->VMM_FLAGS & MAP_ALIGN64K) vrflags |= VR_PHYS64K;
if(m->VMM_FLAGS & MAP_SHARED) vrflags |= VR_SHARED;
if(m->VMM_FLAGS & MAP_CONTIG) vrflags |= VR_CONTIG;
if(len % VM_PAGE_SIZE)
len += VM_PAGE_SIZE - (len % VM_PAGE_SIZE);
if(!(vr = map_page_region(vmp,
arch_vir2map(vmp,
m->VMM_ADDR ? m->VMM_ADDR : vmp->vm_stacktop),
VM_DATATOP, len, MAP_NONE, vrflags, mfflags))) {
return ENOMEM;
}
} else {
return ENOSYS;
}
/* Return mapping, as seen from process. */
assert(vr);
m->VMM_RETADDR = arch_map2vir(vmp, vr->vaddr);
return OK;
}
/*===========================================================================*
* do_remap *
*===========================================================================*/
PUBLIC int do_remap(message *m)
{
int dn, sn;
vir_bytes da, sa, startv;
size_t size;
struct vir_region *vr, *region;
struct vmproc *dvmp, *svmp;
int r;
da = (vir_bytes) m->VMRE_DA;
sa = (vir_bytes) m->VMRE_SA;
size = m->VMRE_SIZE;
if ((r = vm_isokendpt((endpoint_t) m->VMRE_D, &dn)) != OK)
return EINVAL;
if ((r = vm_isokendpt((endpoint_t) m->VMRE_S, &sn)) != OK)
return EINVAL;
dvmp = &vmproc[dn];
svmp = &vmproc[sn];
/* da is not translated by arch_vir2map(),
* it's handled a little differently,
* since in map_remap(), we have to know
* about whether the user needs to bind to
* THAT address or be chosen by the system.
*/
sa = arch_vir2map(svmp, sa);
if (!(region = map_lookup(svmp, sa)))
return EINVAL;
if(region->vaddr != sa) {
printf("VM: do_remap: not start of region.\n");
return EFAULT;
}
if(!(region->flags & VR_SHARED)) {
printf("VM: do_remap: not shared.\n");
return EFAULT;
}
if (size % VM_PAGE_SIZE)
size += VM_PAGE_SIZE - size % VM_PAGE_SIZE;
if(size != region->length) {
printf("VM: do_remap: not size of region.\n");
return EFAULT;
}
if ((r = map_remap(dvmp, da, size, region, &startv)) != OK)
return r;
m->VMRE_RETA = (char *) arch_map2vir(dvmp, startv);
return OK;
}
/*===========================================================================*
* do_map_phys *
*===========================================================================*/
PUBLIC int do_map_phys(message *m)
{
int r, n;
struct vmproc *vmp;
endpoint_t target;
struct vir_region *vr;
vir_bytes len;
phys_bytes startaddr;
size_t offset;
target = m->VMMP_EP;
len = m->VMMP_LEN;
if (len <= 0) return EINVAL;
if(target == SELF)
target = m->m_source;
if((r=vm_isokendpt(target, &n)) != OK)
return EINVAL;
startaddr = (vir_bytes)m->VMMP_PHADDR;
/* First check permission, then round range down/up. Caller can't
* help it if we can't map in lower than page granularity.
*/
if(map_perm_check(m->m_source, target, startaddr, len) != OK) {
printf("VM: unauthorized mapping of 0x%lx by %d\n",
startaddr, m->m_source);
return EPERM;
}
vmp = &vmproc[n];
if(!(vmp->vm_flags & VMF_HASPT))
return ENXIO;
offset = startaddr % VM_PAGE_SIZE;
len += offset;
startaddr -= offset;
if(len % VM_PAGE_SIZE)
len += VM_PAGE_SIZE - (len % VM_PAGE_SIZE);
if(!(vr = map_page_region(vmp, arch_vir2map(vmp, vmp->vm_stacktop),
VM_DATATOP, len, startaddr,
VR_DIRECT | VR_NOPF | VR_WRITABLE, 0))) {
return ENOMEM;
}
m->VMMP_VADDR_REPLY = (void *) (arch_map2vir(vmp, vr->vaddr) + offset);
return OK;
}
int scall_mmap(kipc_msg_t *m)
{
int err, n;
struct vmproc *vmp;
int mfflags = 0;
struct vir_region *vr = NULL;
if((err = vm_isokendpt(m->m_source, &n)) != 0) {
vm_panic("do_mmap: message from strange source", m->m_source);
}
vmp = &vmproc[n];
if(!(vmp->vm_flags & VMF_HASPT))
return -ENXIO;
if(m->VMM_FD == -1 || (m->VMM_FLAGS & MAP_ANONYMOUS)) {
int s;
vir_bytes v;
u32_t vrflags = VR_ANON | VR_WRITABLE;
size_t len = (vir_bytes) m->VMM_LEN;
if(m->VMM_FD != -1) {
return -EINVAL;
}
if(m->VMM_FLAGS & MAP_CONTIG) mfflags |= MF_CONTIG;
if(m->VMM_FLAGS & MAP_PREALLOC) mfflags |= MF_PREALLOC;
if(m->VMM_FLAGS & MAP_LOWER16M) vrflags |= VR_LOWER16MB;
if(m->VMM_FLAGS & MAP_LOWER1M) vrflags |= VR_LOWER1MB;
if(m->VMM_FLAGS & MAP_ALIGN64K) vrflags |= VR_PHYS64K;
if(m->VMM_FLAGS & MAP_SHARED) vrflags |= VR_SHARED;
if(len % VM_PAGE_SIZE)
len += VM_PAGE_SIZE - (len % VM_PAGE_SIZE);
if(!(vr = map_page_region(vmp,
arch_vir2map(vmp, m->VMM_ADDR ? m->VMM_ADDR : vmp->vm_stacktop),
VM_DATATOP, len, MAP_NONE, vrflags, mfflags))) {
return -ENOMEM;
}
} else {
return -ENOSYS;
}
/* Return mapping, as seen from process. */
vm_assert(vr);
m->VMM_RETADDR = arch_map2vir(vmp, vr->vaddr);
return m->VMM_RETADDR;
}
/*===========================================================================*
* 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);
}
}
int scall_munmap(kipc_msg_t *m)
{
int r, n;
struct vmproc *vmp;
vir_bytes addr, len;
struct vir_region *vr;
if((r = vm_isokendpt(m->m_source, &n)) != 0) {
vm_panic("do_mmap: message from strange source", m->m_source);
}
vmp = &vmproc[n];
if (!(vmp->vm_flags & VMF_HASPT))
return -ENXIO;
if (m->m_type == NNR_VM_MUNMAP) {
addr = (vir_bytes) arch_vir2map(vmp, (vir_bytes) m->VMUM_ADDR);
} else if(m->m_type == NNR_VM_MUNMAP_TEXT) {
addr = (vir_bytes) arch_vir2map_text(vmp, (vir_bytes) m->VMUM_ADDR);
} else {
vm_panic("do_munmap: strange type", NO_NUM);
}
if (!(vr = map_lookup(vmp, addr))) {
printk("VM: unmap: virtual address 0x%lx not found in %d\n",
m->VMUM_ADDR, vmp->vm_endpoint);
return -EFAULT;
}
len = m->VMUM_LEN;
if (len % VM_PAGE_SIZE)
len += VM_PAGE_SIZE - (len % VM_PAGE_SIZE);
if (addr != vr->vaddr || len > vr->length || len < VM_PAGE_SIZE) {
return -EFAULT;
}
if (map_unmap_region(vmp, vr, len) != 0)
vm_panic("do_munmap: map_unmap_region failed", NO_NUM);
return 0;
}
/*===========================================================================*
* do_munmap *
*===========================================================================*/
PUBLIC int do_munmap(message *m)
{
int r, n;
struct vmproc *vmp;
vir_bytes addr, len;
struct vir_region *vr;
if((r=vm_isokendpt(m->m_source, &n)) != OK) {
panic("do_mmap: message from strange source: %d", m->m_source);
}
vmp = &vmproc[n];
if(!(vmp->vm_flags & VMF_HASPT))
return ENXIO;
if(m->m_type == VM_MUNMAP) {
addr = (vir_bytes) arch_vir2map(vmp, (vir_bytes) m->VMUM_ADDR);
} else if(m->m_type == VM_MUNMAP_TEXT) {
addr = (vir_bytes) arch_vir2map_text(vmp, (vir_bytes) m->VMUM_ADDR);
} else {
panic("do_munmap: strange type");
}
if(!(vr = map_lookup(vmp, addr))) {
printf("VM: unmap: virtual address %p not found in %d\n",
m->VMUM_ADDR, vmp->vm_endpoint);
return EFAULT;
}
len = m->VMUM_LEN;
if (len % VM_PAGE_SIZE)
len += VM_PAGE_SIZE - (len % VM_PAGE_SIZE);
if(addr != vr->vaddr || len > vr->length || len < VM_PAGE_SIZE) {
return EFAULT;
}
if(map_unmap_region(vmp, vr, len) != OK)
panic("do_munmap: map_unmap_region failed");
return OK;
}
/*===========================================================================*
* vm_addrok *
*===========================================================================*/
PUBLIC int vm_addrok(void *vir, int writeflag)
{
/* Mark a page allocated by vm_allocpage() unwritable, i.e. only for VM. */
pt_t *pt = &vmprocess->vm_pt;
int pde, pte;
vir_bytes v = arch_vir2map(vmprocess, (vir_bytes) vir);
/* No PT yet? Don't bother looking. */
if(!(vmprocess->vm_flags & VMF_HASPT)) {
return 1;
}
pde = I386_VM_PDE(v);
pte = I386_VM_PTE(v);
if(!(pt->pt_dir[pde] & I386_VM_PRESENT)) {
printf("addr not ok: missing pde %d\n", pde);
return 0;
}
if(writeflag &&
!(pt->pt_dir[pde] & I386_VM_WRITE)) {
printf("addr not ok: pde %d present but pde unwritable\n", pde);
return 0;
}
if(!(pt->pt_pt[pde][pte] & I386_VM_PRESENT)) {
printf("addr not ok: missing pde %d / pte %d\n",
pde, pte);
return 0;
}
if(writeflag &&
!(pt->pt_pt[pde][pte] & I386_VM_WRITE)) {
printf("addr not ok: pde %d / pte %d present but unwritable\n",
pde, pte);
return 0;
}
return 1;
}
/*===========================================================================*
* do_remap *
*===========================================================================*/
int do_remap(kipc_msg_t *m)
{
int d, dn, s, sn;
vir_bytes da, sa, startv;
size_t size;
struct vir_region *vr, *region;
struct vmproc *dvmp, *svmp;
int r;
d = m->VMRE_D;
s = m->VMRE_S;
da = (vir_bytes) m->VMRE_DA;
sa = (vir_bytes) m->VMRE_SA;
size = m->VMRE_SIZE;
if ((r = vm_isokendpt(d, &dn)) != 0)
return -EINVAL;
if ((r = vm_isokendpt(s, &sn)) != 0)
return -EINVAL;
dvmp = &vmproc[dn];
svmp = &vmproc[sn];
/* da is not translated by arch_vir2map(),
* it's handled a little differently,
* since in map_remap(), we have to know
* about whether the user needs to bind to
* THAT address or be chosen by the system.
*/
sa = arch_vir2map(svmp, sa);
if (!(region = map_lookup(svmp, sa)))
return -EINVAL;
if ((r = map_remap(dvmp, da, size, region, &startv)) != 0)
return r;
m->VMRE_RETA = (char *) arch_map2vir(dvmp, startv);
return 0;
}
/*===========================================================================*
* do_get_refcount *
*===========================================================================*/
PUBLIC int do_get_refcount(message *m)
{
int r, n;
struct vmproc *vmp;
endpoint_t target;
u8_t cnt;
vir_bytes addr;
target = m->VMREFCNT_ENDPT;
addr = m->VMREFCNT_ADDR;
if ((r = vm_isokendpt(target, &n)) != OK)
return EINVAL;
vmp = &vmproc[n];
addr = arch_vir2map(vmp, addr);
r = map_get_ref(vmp, addr, &cnt);
m->VMREFCNT_RETC = cnt;
return r;
}
/*===========================================================================*
* do_get_phys *
*===========================================================================*/
PUBLIC int do_get_phys(message *m)
{
int r, n;
struct vmproc *vmp;
endpoint_t target;
phys_bytes ret;
vir_bytes addr;
target = m->VMPHYS_ENDPT;
addr = m->VMPHYS_ADDR;
if ((r = vm_isokendpt(target, &n)) != OK)
return EINVAL;
vmp = &vmproc[n];
addr = arch_vir2map(vmp, addr);
r = map_get_phys(vmp, addr, &ret);
m->VMPHYS_RETA = ret;
return r;
}
/*===========================================================================*
* do_shared_unmap *
*===========================================================================*/
PUBLIC int do_shared_unmap(message *m)
{
int r, n;
struct vmproc *vmp;
endpoint_t target;
struct vir_region *vr;
vir_bytes addr;
target = m->VMUN_ENDPT;
if (target == SELF)
target = m->m_source;
if ((r = vm_isokendpt(target, &n)) != OK)
return EINVAL;
vmp = &vmproc[n];
addr = arch_vir2map(vmp, m->VMUN_ADDR);
if(!(vr = map_lookup(vmp, addr))) {
printf("VM: addr 0x%lx not found.\n", m->VMUN_ADDR);
return EFAULT;
}
if(vr->vaddr != addr) {
printf("VM: wrong address for shared_unmap.\n");
return EFAULT;
}
if(!(vr->flags & VR_SHARED)) {
printf("VM: address does not point to shared region.\n");
return EFAULT;
}
if(map_unmap_region(vmp, vr, vr->length) != OK)
panic("do_shared_unmap: map_unmap_region failed");
return OK;
}
/*===========================================================================*
* do_shared_unmap *
*===========================================================================*/
int do_shared_unmap(kipc_msg_t *m)
{
int r, n;
struct vmproc *vmp;
endpoint_t target;
struct vir_region *vr;
vir_bytes addr;
target = m->VMUN_ENDPT;
if ((r = vm_isokendpt(target, &n)) != 0)
return -EINVAL;
vmp = &vmproc[n];
addr = arch_vir2map(vmp, m->VMUN_ADDR);
if(!(vr = map_lookup(vmp, addr))) {
printk("VM: addr 0x%lx not found.\n", m->VMUN_ADDR);
return -EFAULT;
}
if(vr->vaddr != addr) {
printk("VM: wrong address for shared_unmap.\n");
return -EFAULT;
}
if(!(vr->flags & VR_SHARED)) {
printk("VM: address does not point to shared region.\n");
return -EFAULT;
}
if(map_unmap_region(vmp, vr, vr->length) != 0)
vm_panic("do_shared_unmap: map_unmap_region failed", NO_NUM);
return 0;
}
/*===========================================================================*
* 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
}
/*===========================================================================*
* do_fork *
*===========================================================================*/
PUBLIC int do_fork(message *msg)
{
int r, proc, s, childproc, fullvm;
struct vmproc *vmp, *vmc;
pt_t origpt;
vir_bytes msgaddr;
SANITYCHECK(SCL_FUNCTIONS);
if(vm_isokendpt(msg->VMF_ENDPOINT, &proc) != OK) {
printf("VM: bogus endpoint VM_FORK %d\n", msg->VMF_ENDPOINT);
SANITYCHECK(SCL_FUNCTIONS);
return EINVAL;
}
childproc = msg->VMF_SLOTNO;
if(childproc < 0 || childproc >= NR_PROCS) {
printf("VM: bogus slotno VM_FORK %d\n", msg->VMF_SLOTNO);
SANITYCHECK(SCL_FUNCTIONS);
return EINVAL;
}
vmp = &vmproc[proc]; /* parent */
vmc = &vmproc[childproc]; /* child */
assert(vmc->vm_slot == childproc);
if(vmp->vm_flags & VMF_HAS_DMA) {
printf("VM: %d has DMA memory and may not fork\n", msg->VMF_ENDPOINT);
return EINVAL;
}
fullvm = vmp->vm_flags & VMF_HASPT;
/* The child is basically a copy of the parent. */
origpt = vmc->vm_pt;
*vmc = *vmp;
vmc->vm_slot = childproc;
vmc->vm_regions = NULL;
yielded_init(&vmc->vm_yielded_blocks);
vmc->vm_endpoint = NONE; /* In case someone tries to use it. */
vmc->vm_pt = origpt;
vmc->vm_flags &= ~VMF_HASPT;
#if VMSTATS
vmc->vm_bytecopies = 0;
#endif
if(pt_new(&vmc->vm_pt) != OK) {
printf("VM: fork: pt_new failed\n");
return ENOMEM;
}
vmc->vm_flags |= VMF_HASPT;
if(fullvm) {
SANITYCHECK(SCL_DETAIL);
if(map_proc_copy(vmc, vmp) != OK) {
printf("VM: fork: map_proc_copy failed\n");
pt_free(&vmc->vm_pt);
return(ENOMEM);
}
if(vmp->vm_heap) {
vmc->vm_heap = map_region_lookup_tag(vmc, VRT_HEAP);
assert(vmc->vm_heap);
}
SANITYCHECK(SCL_DETAIL);
} else {
vir_bytes sp;
struct vir_region *heap, *stack;
vir_bytes text_bytes, data_bytes, stack_bytes, parent_gap_bytes,
child_gap_bytes;
/* Get SP of new process (using parent). */
if(get_stack_ptr(vmp->vm_endpoint, &sp) != OK) {
printf("VM: fork: get_stack_ptr failed for %d\n",
vmp->vm_endpoint);
return ENOMEM;
}
/* Update size of stack segment using current SP. */
if(adjust(vmp, vmp->vm_arch.vm_seg[D].mem_len, sp) != OK) {
printf("VM: fork: adjust failed for %d\n",
vmp->vm_endpoint);
return ENOMEM;
}
/* Copy newly adjust()ed stack segment size to child. */
vmc->vm_arch.vm_seg[S] = vmp->vm_arch.vm_seg[S];
text_bytes = CLICK2ABS(vmc->vm_arch.vm_seg[T].mem_len);
data_bytes = CLICK2ABS(vmc->vm_arch.vm_seg[D].mem_len);
stack_bytes = CLICK2ABS(vmc->vm_arch.vm_seg[S].mem_len);
/* how much space after break and before lower end (which is the
* logical top) of stack for the parent
*/
parent_gap_bytes = CLICK2ABS(vmc->vm_arch.vm_seg[S].mem_vir -
vmc->vm_arch.vm_seg[D].mem_len);
/* how much space can the child stack grow downwards, below
* the current SP? The rest of the gap is available for the
* heap to grow upwards.
*/
child_gap_bytes = VM_PAGE_SIZE;
if((r=proc_new(vmc, VM_PROCSTART,
text_bytes, data_bytes, stack_bytes, child_gap_bytes, 0, 0,
CLICK2ABS(vmc->vm_arch.vm_seg[S].mem_vir +
vmc->vm_arch.vm_seg[S].mem_len), 1)) != OK) {
printf("VM: fork: proc_new failed\n");
return r;
}
if(!(heap = map_region_lookup_tag(vmc, VRT_HEAP)))
panic("couldn't lookup heap");
assert(heap->phys);
if(!(stack = map_region_lookup_tag(vmc, VRT_STACK)))
panic("couldn't lookup stack");
assert(stack->phys);
/* Now copy the memory regions. */
if(vmc->vm_arch.vm_seg[T].mem_len > 0) {
struct vir_region *text;
if(!(text = map_region_lookup_tag(vmc, VRT_TEXT)))
panic("couldn't lookup text");
assert(text->phys);
if(copy_abs2region(CLICK2ABS(vmp->vm_arch.vm_seg[T].mem_phys),
text, 0, text_bytes) != OK)
panic("couldn't copy text");
}
if(copy_abs2region(CLICK2ABS(vmp->vm_arch.vm_seg[D].mem_phys),
heap, 0, data_bytes) != OK)
panic("couldn't copy heap");
if(copy_abs2region(CLICK2ABS(vmp->vm_arch.vm_seg[D].mem_phys +
vmc->vm_arch.vm_seg[D].mem_len) + parent_gap_bytes,
stack, child_gap_bytes, stack_bytes) != OK)
panic("couldn't copy stack");
}
/* Only inherit these flags. */
vmc->vm_flags &= (VMF_INUSE|VMF_SEPARATE|VMF_HASPT);
/* inherit the priv call bitmaps */
memcpy(&vmc->vm_call_mask, &vmp->vm_call_mask, sizeof(vmc->vm_call_mask));
/* Tell kernel about the (now successful) FORK. */
if((r=sys_fork(vmp->vm_endpoint, childproc,
&vmc->vm_endpoint, vmc->vm_arch.vm_seg,
PFF_VMINHIBIT, &msgaddr)) != OK) {
panic("do_fork can't sys_fork: %d", r);
}
if(fullvm) {
vir_bytes vir;
/* making these messages writable is an optimisation
* and its return value needn't be checked.
*/
vir = arch_vir2map(vmc, msgaddr);
handle_memory(vmc, vir, sizeof(message), 1);
vir = arch_vir2map(vmp, msgaddr);
handle_memory(vmp, vir, sizeof(message), 1);
}
if((r=pt_bind(&vmc->vm_pt, vmc)) != OK)
panic("fork can't pt_bind: %d", r);
/* Inform caller of new child endpoint. */
msg->VMF_CHILD_ENDPOINT = vmc->vm_endpoint;
SANITYCHECK(SCL_FUNCTIONS);
return OK;
}
/*===========================================================================*
* 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;
}
