minix/servers/vm/mmap.c
David van Moolenbroek 46fca87456 VM: munmap fix
2012-10-13 19:08:28 +02:00

389 lines
9 KiB
C

#define _SYSTEM 1
#include <minix/callnr.h>
#include <minix/com.h>
#include <minix/config.h>
#include <minix/const.h>
#include <minix/ds.h>
#include <minix/endpoint.h>
#include <minix/keymap.h>
#include <minix/minlib.h>
#include <minix/type.h>
#include <minix/ipc.h>
#include <minix/sysutil.h>
#include <minix/syslib.h>
#include <minix/safecopies.h>
#include <minix/bitmap.h>
#include <minix/debug.h>
#include <sys/mman.h>
#include <sys/param.h>
#include <errno.h>
#include <assert.h>
#include <string.h>
#include <env.h>
#include <stdio.h>
#include <fcntl.h>
#include <memory.h>
#include "glo.h"
#include "proto.h"
#include "util.h"
#include "region.h"
/*===========================================================================*
* do_mmap *
*===========================================================================*/
int do_mmap(message *m)
{
int r, n;
struct vmproc *vmp;
int mfflags = 0;
vir_bytes addr;
struct vir_region *vr = NULL;
int execpriv = 0;
/* RS and VFS can do slightly more special mmap() things */
if(m->m_source == VFS_PROC_NR || m->m_source == RS_PROC_NR)
execpriv = 1;
if(m->VMM_FLAGS & MAP_THIRDPARTY) {
if(!execpriv) return EPERM;
if((r=vm_isokendpt(m->VMM_FORWHOM, &n)) != OK)
return ESRCH;
} else {
/* regular mmap, i.e. for caller */
if((r=vm_isokendpt(m->m_source, &n)) != OK) {
panic("do_mmap: message from strange source: %d",
m->m_source);
}
}
vmp = &vmproc[n];
if(m->VMM_FD == -1 || (m->VMM_FLAGS & MAP_ANON)) {
mem_type_t *mt;
u32_t vrflags = VR_ANON | VR_WRITABLE;
size_t len = (vir_bytes) m->VMM_LEN;
if(m->VMM_FD != -1 || len <= 0) {
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_UNINITIALIZED) {
if(!execpriv) return EPERM;
vrflags |= VR_UNINITIALIZED;
}
if(m->VMM_FLAGS & MAP_CONTIG) {
vrflags |= VR_CONTIG;
mt = &mem_type_anon_contig;
} else mt = &mem_type_anon;
if(len % VM_PAGE_SIZE)
len += VM_PAGE_SIZE - (len % VM_PAGE_SIZE);
vr = NULL;
if (m->VMM_ADDR || (m->VMM_FLAGS & MAP_FIXED)) {
/* An address is given, first try at that address. */
addr = m->VMM_ADDR;
vr = map_page_region(vmp, addr, 0, len,
vrflags, mfflags, mt);
if(!vr && (m->VMM_FLAGS & MAP_FIXED))
return ENOMEM;
}
if (!vr) {
/* No address given or address already in use. */
vr = map_page_region(vmp, 0, VM_DATATOP, len,
vrflags, mfflags, mt);
}
if (!vr) {
return ENOMEM;
}
} else {
return ENOSYS;
}
/* Return mapping, as seen from process. */
assert(vr);
m->VMM_RETADDR = vr->vaddr;
return OK;
}
/*===========================================================================*
* map_perm_check *
*===========================================================================*/
int map_perm_check(endpoint_t caller, endpoint_t target,
phys_bytes physaddr, phys_bytes len)
{
int r;
/* TTY and memory are allowed to do anything.
* They have to be special cases as they have to be able to do
* anything; TTY even on behalf of anyone for the TIOCMAPMEM
* ioctl. MEM just for itself.
*/
if(caller == TTY_PROC_NR)
return OK;
if(caller != target)
return EPERM;
if(caller == MEM_PROC_NR)
return OK;
/* Anyone else needs explicit permission from the kernel (ultimately
* set by PCI).
*/
r = sys_privquery_mem(caller, physaddr, len);
return r;
}
/*===========================================================================*
* do_map_phys *
*===========================================================================*/
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];
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, 0, VM_DATATOP, len,
VR_DIRECT | VR_WRITABLE, 0, &mem_type_directphys))) {
return ENOMEM;
}
phys_setphys(vr, startaddr);
m->VMMP_VADDR_REPLY = (void *) (vr->vaddr + offset);
return OK;
}
/*===========================================================================*
* do_remap *
*===========================================================================*/
int do_remap(message *m)
{
int dn, sn;
vir_bytes da, sa;
size_t size;
u32_t flags;
struct vir_region *src_region, *vr;
struct vmproc *dvmp, *svmp;
int r;
int readonly;
if(m->m_type == VM_REMAP)
readonly = 0;
else if(m->m_type == VM_REMAP_RO)
readonly = 1;
else panic("do_remap: can't be");
da = (vir_bytes) m->VMRE_DA;
sa = (vir_bytes) m->VMRE_SA;
size = m->VMRE_SIZE;
if (size <= 0) return EINVAL;
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];
if (!(src_region = map_lookup(svmp, sa, NULL)))
return EINVAL;
if(src_region->vaddr != sa) {
printf("VM: do_remap: not start of region.\n");
return EFAULT;
}
if (size % VM_PAGE_SIZE)
size += VM_PAGE_SIZE - size % VM_PAGE_SIZE;
if(size != src_region->length) {
printf("VM: do_remap: not size of region.\n");
return EFAULT;
}
flags = VR_SHARED;
if(!readonly)
flags |= VR_WRITABLE;
if(da)
vr = map_page_region(dvmp, da, 0, size, flags, 0,
&mem_type_shared);
else
vr = map_page_region(dvmp, 0, VM_DATATOP, size, flags, 0,
&mem_type_shared);
if(!vr) {
printf("VM: re-map of shared area failed\n");
return ENOMEM;
}
shared_setsource(vr, svmp->vm_endpoint, src_region);
m->VMRE_RETA = (char *) vr->vaddr;
return OK;
}
/*===========================================================================*
* do_get_phys *
*===========================================================================*/
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];
r = map_get_phys(vmp, addr, &ret);
m->VMPHYS_RETA = ret;
return r;
}
/*===========================================================================*
* do_get_refcount *
*===========================================================================*/
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];
r = map_get_ref(vmp, addr, &cnt);
m->VMREFCNT_RETC = cnt;
return r;
}
/*===========================================================================*
* do_munmap *
*===========================================================================*/
int do_munmap(message *m)
{
int r, n;
struct vmproc *vmp;
vir_bytes addr, len, offset;
struct vir_region *vr;
endpoint_t target = SELF;
if(m->m_type == VM_UNMAP_PHYS) {
target = m->VMUP_EP;
} else if(m->m_type == VM_SHM_UNMAP) {
target = m->VMUN_ENDPT;
}
if(target == SELF)
target = m->m_source;
if((r=vm_isokendpt(target, &n)) != OK) {
panic("do_mmap: message from strange source: %d", m->m_source);
}
vmp = &vmproc[n];
if(m->m_type == VM_UNMAP_PHYS) {
addr = (vir_bytes) m->VMUP_VADDR;
} else if(m->m_type == VM_SHM_UNMAP) {
addr = (vir_bytes) m->VMUN_ADDR;
} else addr = (vir_bytes) m->VMUM_ADDR;
if(!(vr = map_lookup(vmp, addr, NULL))) {
printf("VM: unmap: virtual address 0x%lx not found in %d\n",
addr, target);
return EFAULT;
}
if(addr % VM_PAGE_SIZE)
return EFAULT;
if(m->m_type == VM_UNMAP_PHYS || m->m_type == VM_SHM_UNMAP) {
len = vr->length;
} else len = roundup(m->VMUM_LEN, VM_PAGE_SIZE);
offset = addr - vr->vaddr;
if(offset + len > vr->length) {
printf("munmap: addr 0x%lx len 0x%lx spills out of region\n",
addr, len);
return EFAULT;
}
if(map_unmap_region(vmp, vr, offset, len) != OK)
panic("do_munmap: map_unmap_region failed");
return OK;
}