File: [local] / src / sys / uvm / uvm_mmap.c (download)
Revision 1.191, Fri Apr 5 14:16:05 2024 UTC (2 months ago) by deraadt
Branch: MAIN
CVS Tags: HEAD
Changes since 1.190: +1 -10 lines
delete msyscall stub
|
/* $OpenBSD: uvm_mmap.c,v 1.191 2024/04/05 14:16:05 deraadt Exp $ */
/* $NetBSD: uvm_mmap.c,v 1.49 2001/02/18 21:19:08 chs Exp $ */
/*
* Copyright (c) 1997 Charles D. Cranor and Washington University.
* Copyright (c) 1991, 1993 The Regents of the University of California.
* Copyright (c) 1988 University of Utah.
*
* All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* the Systems Programming Group of the University of Utah Computer
* Science Department.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* from: Utah $Hdr: vm_mmap.c 1.6 91/10/21$
* @(#)vm_mmap.c 8.5 (Berkeley) 5/19/94
* from: Id: uvm_mmap.c,v 1.1.2.14 1998/01/05 21:04:26 chuck Exp
*/
/*
* uvm_mmap.c: system call interface into VM system, plus kernel vm_mmap
* function.
*/
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/fcntl.h>
#include <sys/file.h>
#include <sys/filedesc.h>
#include <sys/resourcevar.h>
#include <sys/mman.h>
#include <sys/mount.h>
#include <sys/proc.h>
#include <sys/malloc.h>
#include <sys/vnode.h>
#include <sys/conf.h>
#include <sys/signalvar.h>
#include <sys/syslog.h>
#include <sys/stat.h>
#include <sys/specdev.h>
#include <sys/stdint.h>
#include <sys/pledge.h>
#include <sys/unistd.h> /* for KBIND* */
#include <sys/user.h>
#include <machine/exec.h> /* for __LDPGSZ */
#include <sys/syscall.h>
#include <sys/syscallargs.h>
#include <uvm/uvm.h>
#include <uvm/uvm_device.h>
#include <uvm/uvm_vnode.h>
int uvm_mmapanon(vm_map_t, vaddr_t *, vsize_t, vm_prot_t, vm_prot_t, int,
vsize_t, struct proc *);
int uvm_mmapfile(vm_map_t, vaddr_t *, vsize_t, vm_prot_t, vm_prot_t, int,
struct vnode *, voff_t, vsize_t, struct proc *);
/*
* Page align addr and size, returning EINVAL on wraparound.
*/
#define ALIGN_ADDR(addr, size, pageoff) do { \
pageoff = (addr & PAGE_MASK); \
if (pageoff != 0) { \
if (size > SIZE_MAX - pageoff) \
return EINVAL; /* wraparound */ \
addr -= pageoff; \
size += pageoff; \
} \
if (size != 0) { \
size = (vsize_t)round_page(size); \
if (size == 0) \
return EINVAL; /* wraparound */ \
} \
} while (0)
/*
* sys_mquery: provide mapping hints to applications that do fixed mappings
*
* flags: 0 or MAP_FIXED (MAP_FIXED - means that we insist on this addr and
* don't care about PMAP_PREFER or such)
* addr: hint where we'd like to place the mapping.
* size: size of the mapping
* fd: fd of the file we want to map
* off: offset within the file
*/
int
sys_mquery(struct proc *p, void *v, register_t *retval)
{
struct sys_mquery_args /* {
syscallarg(void *) addr;
syscallarg(size_t) len;
syscallarg(int) prot;
syscallarg(int) flags;
syscallarg(int) fd;
syscallarg(off_t) pos;
} */ *uap = v;
struct file *fp;
voff_t uoff;
int error;
vaddr_t vaddr;
int flags = 0;
vsize_t size;
vm_prot_t prot;
int fd;
vaddr = (vaddr_t) SCARG(uap, addr);
prot = SCARG(uap, prot);
size = (vsize_t) SCARG(uap, len);
fd = SCARG(uap, fd);
if ((prot & PROT_MASK) != prot)
return EINVAL;
if (SCARG(uap, flags) & MAP_FIXED)
flags |= UVM_FLAG_FIXED;
if (fd >= 0) {
if ((error = getvnode(p, fd, &fp)) != 0)
return error;
uoff = SCARG(uap, pos);
} else {
fp = NULL;
uoff = UVM_UNKNOWN_OFFSET;
}
if (vaddr == 0)
vaddr = uvm_map_hint(p->p_vmspace, prot, VM_MIN_ADDRESS,
VM_MAXUSER_ADDRESS);
error = uvm_map_mquery(&p->p_vmspace->vm_map, &vaddr, size, uoff,
flags);
if (error == 0)
*retval = (register_t)(vaddr);
if (fp != NULL)
FRELE(fp, p);
return error;
}
int uvm_wxabort;
/*
* W^X violations are only allowed on permitted filesystems.
*/
static inline int
uvm_wxcheck(struct proc *p, char *call)
{
struct process *pr = p->p_p;
int wxallowed = (pr->ps_textvp->v_mount &&
(pr->ps_textvp->v_mount->mnt_flag & MNT_WXALLOWED));
if (wxallowed && (pr->ps_flags & PS_WXNEEDED))
return 0;
if (uvm_wxabort) {
KERNEL_LOCK();
/* Report W^X failures */
if (pr->ps_wxcounter++ == 0)
log(LOG_NOTICE, "%s(%d): %s W^X violation\n",
pr->ps_comm, pr->ps_pid, call);
/* Send uncatchable SIGABRT for coredump */
sigexit(p, SIGABRT);
KERNEL_UNLOCK();
}
return ENOTSUP;
}
/*
* sys_mmap: mmap system call.
*
* => file offset and address may not be page aligned
* - if MAP_FIXED, offset and address must have remainder mod PAGE_SIZE
* - if address isn't page aligned the mapping starts at trunc_page(addr)
* and the return value is adjusted up by the page offset.
*/
int
sys_mmap(struct proc *p, void *v, register_t *retval)
{
struct sys_mmap_args /* {
syscallarg(void *) addr;
syscallarg(size_t) len;
syscallarg(int) prot;
syscallarg(int) flags;
syscallarg(int) fd;
syscallarg(off_t) pos;
} */ *uap = v;
vaddr_t addr;
struct vattr va;
off_t pos;
vsize_t limit, pageoff, size;
vm_prot_t prot, maxprot;
int flags, fd;
vaddr_t vm_min_address = VM_MIN_ADDRESS;
struct filedesc *fdp = p->p_fd;
struct file *fp = NULL;
struct vnode *vp;
int error;
/* first, extract syscall args from the uap. */
addr = (vaddr_t) SCARG(uap, addr);
size = (vsize_t) SCARG(uap, len);
prot = SCARG(uap, prot);
flags = SCARG(uap, flags);
fd = SCARG(uap, fd);
pos = SCARG(uap, pos);
/*
* Validate the flags.
*/
if ((prot & PROT_MASK) != prot)
return EINVAL;
if ((prot & (PROT_WRITE | PROT_EXEC)) == (PROT_WRITE | PROT_EXEC) &&
(error = uvm_wxcheck(p, "mmap")))
return error;
if ((flags & MAP_FLAGMASK) != flags)
return EINVAL;
if ((flags & (MAP_SHARED|MAP_PRIVATE)) == (MAP_SHARED|MAP_PRIVATE))
return EINVAL;
if ((flags & (MAP_FIXED|__MAP_NOREPLACE)) == __MAP_NOREPLACE)
return EINVAL;
if (flags & MAP_STACK) {
if ((flags & (MAP_ANON|MAP_PRIVATE)) != (MAP_ANON|MAP_PRIVATE))
return EINVAL;
if (flags & ~(MAP_STACK|MAP_FIXED|MAP_ANON|MAP_PRIVATE))
return EINVAL;
if (pos != 0)
return EINVAL;
if ((prot & (PROT_READ|PROT_WRITE)) != (PROT_READ|PROT_WRITE))
return EINVAL;
}
if (size == 0)
return EINVAL;
error = pledge_protexec(p, prot);
if (error)
return error;
/* align file position and save offset. adjust size. */
ALIGN_ADDR(pos, size, pageoff);
/* now check (MAP_FIXED) or get (!MAP_FIXED) the "addr" */
if (flags & MAP_FIXED) {
/* adjust address by the same amount as we did the offset */
addr -= pageoff;
if (addr & PAGE_MASK)
return EINVAL; /* not page aligned */
if (addr > SIZE_MAX - size)
return EINVAL; /* no wrapping! */
if (VM_MAXUSER_ADDRESS > 0 &&
(addr + size) > VM_MAXUSER_ADDRESS)
return EINVAL;
if (vm_min_address > 0 && addr < vm_min_address)
return EINVAL;
}
/* check for file mappings (i.e. not anonymous) and verify file. */
if ((flags & MAP_ANON) == 0) {
KERNEL_LOCK();
if ((fp = fd_getfile(fdp, fd)) == NULL) {
error = EBADF;
goto out;
}
if (fp->f_type != DTYPE_VNODE) {
error = ENODEV; /* only mmap vnodes! */
goto out;
}
vp = (struct vnode *)fp->f_data; /* convert to vnode */
if (vp->v_type != VREG && vp->v_type != VCHR &&
vp->v_type != VBLK) {
error = ENODEV; /* only REG/CHR/BLK support mmap */
goto out;
}
if (vp->v_type == VREG && (pos + size) < pos) {
error = EINVAL; /* no offset wrapping */
goto out;
}
/* special case: catch SunOS style /dev/zero */
if (vp->v_type == VCHR && iszerodev(vp->v_rdev)) {
flags |= MAP_ANON;
FRELE(fp, p);
fp = NULL;
KERNEL_UNLOCK();
goto is_anon;
}
/*
* Old programs may not select a specific sharing type, so
* default to an appropriate one.
*/
if ((flags & (MAP_SHARED|MAP_PRIVATE)) == 0) {
#if defined(DEBUG)
printf("WARNING: defaulted mmap() share type to"
" %s (pid %d comm %s)\n",
vp->v_type == VCHR ? "MAP_SHARED" : "MAP_PRIVATE",
p->p_p->ps_pid, p->p_p->ps_comm);
#endif
if (vp->v_type == VCHR)
flags |= MAP_SHARED; /* for a device */
else
flags |= MAP_PRIVATE; /* for a file */
}
/*
* MAP_PRIVATE device mappings don't make sense (and aren't
* supported anyway). However, some programs rely on this,
* so just change it to MAP_SHARED.
*/
if (vp->v_type == VCHR && (flags & MAP_PRIVATE) != 0) {
flags = (flags & ~MAP_PRIVATE) | MAP_SHARED;
}
/* now check protection */
maxprot = PROT_EXEC;
/* check read access */
if (fp->f_flag & FREAD)
maxprot |= PROT_READ;
else if (prot & PROT_READ) {
error = EACCES;
goto out;
}
/* check write access, shared case first */
if (flags & MAP_SHARED) {
/*
* if the file is writable, only add PROT_WRITE to
* maxprot if the file is not immutable, append-only.
* otherwise, if we have asked for PROT_WRITE, return
* EPERM.
*/
if (fp->f_flag & FWRITE) {
error = VOP_GETATTR(vp, &va, p->p_ucred, p);
if (error)
goto out;
if ((va.va_flags & (IMMUTABLE|APPEND)) == 0)
maxprot |= PROT_WRITE;
else if (prot & PROT_WRITE) {
error = EPERM;
goto out;
}
} else if (prot & PROT_WRITE) {
error = EACCES;
goto out;
}
} else {
/* MAP_PRIVATE mappings can always write to */
maxprot |= PROT_WRITE;
}
if ((flags & __MAP_NOFAULT) != 0 ||
((flags & MAP_PRIVATE) != 0 && (prot & PROT_WRITE) != 0)) {
limit = lim_cur(RLIMIT_DATA);
if (limit < size ||
limit - size < ptoa(p->p_vmspace->vm_dused)) {
error = ENOMEM;
goto out;
}
}
error = uvm_mmapfile(&p->p_vmspace->vm_map, &addr, size, prot,
maxprot, flags, vp, pos, lim_cur(RLIMIT_MEMLOCK), p);
FRELE(fp, p);
KERNEL_UNLOCK();
} else { /* MAP_ANON case */
if (fd != -1)
return EINVAL;
is_anon: /* label for SunOS style /dev/zero */
/* __MAP_NOFAULT only makes sense with a backing object */
if ((flags & __MAP_NOFAULT) != 0)
return EINVAL;
if (prot != PROT_NONE || (flags & MAP_SHARED)) {
limit = lim_cur(RLIMIT_DATA);
if (limit < size ||
limit - size < ptoa(p->p_vmspace->vm_dused)) {
return ENOMEM;
}
}
/*
* We've been treating (MAP_SHARED|MAP_PRIVATE) == 0 as
* MAP_PRIVATE, so make that clear.
*/
if ((flags & MAP_SHARED) == 0)
flags |= MAP_PRIVATE;
maxprot = PROT_MASK;
error = uvm_mmapanon(&p->p_vmspace->vm_map, &addr, size, prot,
maxprot, flags, lim_cur(RLIMIT_MEMLOCK), p);
}
if (error == 0)
/* remember to add offset */
*retval = (register_t)(addr + pageoff);
return error;
out:
KERNEL_UNLOCK();
if (fp)
FRELE(fp, p);
return error;
}
/*
* sys_msync: the msync system call (a front-end for flush)
*/
int
sys_msync(struct proc *p, void *v, register_t *retval)
{
struct sys_msync_args /* {
syscallarg(void *) addr;
syscallarg(size_t) len;
syscallarg(int) flags;
} */ *uap = v;
vaddr_t addr;
vsize_t size, pageoff;
int flags, uvmflags;
/* extract syscall args from the uap */
addr = (vaddr_t)SCARG(uap, addr);
size = (vsize_t)SCARG(uap, len);
flags = SCARG(uap, flags);
/* sanity check flags */
if ((flags & ~(MS_ASYNC | MS_SYNC | MS_INVALIDATE)) != 0 ||
(flags & (MS_ASYNC | MS_SYNC | MS_INVALIDATE)) == 0 ||
(flags & (MS_ASYNC | MS_SYNC)) == (MS_ASYNC | MS_SYNC))
return EINVAL;
if ((flags & (MS_ASYNC | MS_SYNC)) == 0)
flags |= MS_SYNC;
/* align the address to a page boundary, and adjust the size accordingly */
ALIGN_ADDR(addr, size, pageoff);
if (addr > SIZE_MAX - size)
return EINVAL; /* disallow wrap-around. */
/* translate MS_ flags into PGO_ flags */
uvmflags = PGO_CLEANIT;
if (flags & MS_INVALIDATE)
uvmflags |= PGO_FREE;
if (flags & MS_SYNC)
uvmflags |= PGO_SYNCIO;
else
uvmflags |= PGO_SYNCIO; /* XXXCDC: force sync for now! */
return uvm_map_clean(&p->p_vmspace->vm_map, addr, addr+size, uvmflags);
}
/*
* sys_munmap: unmap a users memory
*/
int
sys_munmap(struct proc *p, void *v, register_t *retval)
{
struct sys_munmap_args /* {
syscallarg(void *) addr;
syscallarg(size_t) len;
} */ *uap = v;
vaddr_t addr;
vsize_t size, pageoff;
vm_map_t map;
vaddr_t vm_min_address = VM_MIN_ADDRESS;
struct uvm_map_deadq dead_entries;
/* get syscall args... */
addr = (vaddr_t) SCARG(uap, addr);
size = (vsize_t) SCARG(uap, len);
/* align address to a page boundary, and adjust size accordingly */
ALIGN_ADDR(addr, size, pageoff);
/*
* Check for illegal addresses. Watch out for address wrap...
* Note that VM_*_ADDRESS are not constants due to casts (argh).
*/
if (addr > SIZE_MAX - size)
return EINVAL;
if (VM_MAXUSER_ADDRESS > 0 && addr + size > VM_MAXUSER_ADDRESS)
return EINVAL;
if (vm_min_address > 0 && addr < vm_min_address)
return EINVAL;
map = &p->p_vmspace->vm_map;
vm_map_lock(map); /* lock map so we can checkprot */
/*
* interesting system call semantic: make sure entire range is
* allocated before allowing an unmap.
*/
if (!uvm_map_checkprot(map, addr, addr + size, PROT_NONE)) {
vm_map_unlock(map);
return EINVAL;
}
TAILQ_INIT(&dead_entries);
if (uvm_unmap_remove(map, addr, addr + size, &dead_entries,
FALSE, TRUE, TRUE) != 0) {
vm_map_unlock(map);
return EPERM; /* immutable entries found */
}
vm_map_unlock(map); /* and unlock */
uvm_unmap_detach(&dead_entries, 0);
return 0;
}
/*
* sys_mprotect: the mprotect system call
*/
int
sys_mprotect(struct proc *p, void *v, register_t *retval)
{
struct sys_mprotect_args /* {
syscallarg(void *) addr;
syscallarg(size_t) len;
syscallarg(int) prot;
} */ *uap = v;
vaddr_t addr;
vsize_t size, pageoff;
vm_prot_t prot;
int error;
/*
* extract syscall args from uap
*/
addr = (vaddr_t)SCARG(uap, addr);
size = (vsize_t)SCARG(uap, len);
prot = SCARG(uap, prot);
if ((prot & PROT_MASK) != prot)
return EINVAL;
if ((prot & (PROT_WRITE | PROT_EXEC)) == (PROT_WRITE | PROT_EXEC) &&
(error = uvm_wxcheck(p, "mprotect")))
return error;
error = pledge_protexec(p, prot);
if (error)
return error;
/*
* align the address to a page boundary, and adjust the size accordingly
*/
ALIGN_ADDR(addr, size, pageoff);
if (addr > SIZE_MAX - size)
return EINVAL; /* disallow wrap-around. */
return (uvm_map_protect(&p->p_vmspace->vm_map, addr, addr+size,
prot, 0, FALSE, TRUE));
}
/*
* sys_pinsyscalls. The caller is required to normalize base,len
* to the minimum .text region, and adjust pintable offsets relative
* to that base.
*/
int
sys_pinsyscalls(struct proc *p, void *v, register_t *retval)
{
struct sys_pinsyscalls_args /* {
syscallarg(void *) base;
syscallarg(size_t) len;
syscallarg(u_int *) pins;
syscallarg(int) npins;
} */ *uap = v;
struct process *pr = p->p_p;
struct vm_map *map = &p->p_vmspace->vm_map;
int npins, error = 0, i;
vaddr_t base;
size_t len;
u_int *pins;
if (pr->ps_libcpin.pn_start ||
(pr->ps_vmspace->vm_map.flags & VM_MAP_PINSYSCALL_ONCE))
return (EPERM);
base = (vaddr_t)SCARG(uap, base);
len = (vsize_t)SCARG(uap, len);
if (base > SIZE_MAX - len)
return (EINVAL); /* disallow wrap-around. */
if (base < map->min_offset || base+len > map->max_offset)
return (EINVAL);
/* XXX MP unlock */
npins = SCARG(uap, npins);
if (npins < 1 || npins > SYS_MAXSYSCALL)
return (E2BIG);
pins = malloc(npins * sizeof(u_int), M_PINSYSCALL, M_WAITOK|M_ZERO);
if (pins == NULL)
return (ENOMEM);
error = copyin(SCARG(uap, pins), pins, npins * sizeof(u_int));
if (error)
goto err;
/* Range-check pintable offsets */
for (i = 0; i < npins; i++) {
if (pins[i] == (u_int)-1 || pins[i] == 0)
continue;
if (pins[i] > SCARG(uap, len)) {
error = ERANGE;
break;
}
}
if (error) {
err:
free(pins, M_PINSYSCALL, npins * sizeof(u_int));
return (error);
}
pr->ps_libcpin.pn_start = base;
pr->ps_libcpin.pn_end = base + len;
pr->ps_libcpin.pn_pins = pins;
pr->ps_libcpin.pn_npins = npins;
pr->ps_flags |= PS_LIBCPIN;
#ifdef PMAP_CHECK_COPYIN
/* Assume (and insist) on libc.so text being execute-only */
if (PMAP_CHECK_COPYIN)
uvm_map_check_copyin_add(map, base, base+len);
#endif
return (0);
}
/*
* sys_mimmutable: the mimmutable system call
*/
int
sys_mimmutable(struct proc *p, void *v, register_t *retval)
{
struct sys_mimmutable_args /* {
immutablearg(void *) addr;
immutablearg(size_t) len;
} */ *uap = v;
vaddr_t addr;
vsize_t size, pageoff;
addr = (vaddr_t)SCARG(uap, addr);
size = (vsize_t)SCARG(uap, len);
/*
* align the address to a page boundary, and adjust the size accordingly
*/
ALIGN_ADDR(addr, size, pageoff);
if (addr > SIZE_MAX - size)
return EINVAL; /* disallow wrap-around. */
return uvm_map_immutable(&p->p_vmspace->vm_map, addr, addr+size, 1);
}
/*
* sys_minherit: the minherit system call
*/
int
sys_minherit(struct proc *p, void *v, register_t *retval)
{
struct sys_minherit_args /* {
syscallarg(void *) addr;
syscallarg(size_t) len;
syscallarg(int) inherit;
} */ *uap = v;
vaddr_t addr;
vsize_t size, pageoff;
vm_inherit_t inherit;
addr = (vaddr_t)SCARG(uap, addr);
size = (vsize_t)SCARG(uap, len);
inherit = SCARG(uap, inherit);
/*
* align the address to a page boundary, and adjust the size accordingly
*/
ALIGN_ADDR(addr, size, pageoff);
if (addr > SIZE_MAX - size)
return EINVAL; /* disallow wrap-around. */
return (uvm_map_inherit(&p->p_vmspace->vm_map, addr, addr+size,
inherit));
}
/*
* sys_madvise: give advice about memory usage.
*/
int
sys_madvise(struct proc *p, void *v, register_t *retval)
{
struct sys_madvise_args /* {
syscallarg(void *) addr;
syscallarg(size_t) len;
syscallarg(int) behav;
} */ *uap = v;
vaddr_t addr;
vsize_t size, pageoff;
int advice, error;
addr = (vaddr_t)SCARG(uap, addr);
size = (vsize_t)SCARG(uap, len);
advice = SCARG(uap, behav);
/*
* align the address to a page boundary, and adjust the size accordingly
*/
ALIGN_ADDR(addr, size, pageoff);
if (addr > SIZE_MAX - size)
return EINVAL; /* disallow wrap-around. */
switch (advice) {
case MADV_NORMAL:
case MADV_RANDOM:
case MADV_SEQUENTIAL:
error = uvm_map_advice(&p->p_vmspace->vm_map, addr,
addr + size, advice);
break;
case MADV_WILLNEED:
/*
* Activate all these pages, pre-faulting them in if
* necessary.
*/
/*
* XXX IMPLEMENT ME.
* Should invent a "weak" mode for uvm_fault()
* which would only do the PGO_LOCKED pgo_get().
*/
return 0;
case MADV_DONTNEED:
/*
* Deactivate all these pages. We don't need them
* any more. We don't, however, toss the data in
* the pages.
*/
error = uvm_map_clean(&p->p_vmspace->vm_map, addr, addr + size,
PGO_DEACTIVATE);
break;
case MADV_FREE:
/*
* These pages contain no valid data, and may be
* garbage-collected. Toss all resources, including
* any swap space in use.
*/
error = uvm_map_clean(&p->p_vmspace->vm_map, addr, addr + size,
PGO_FREE);
break;
case MADV_SPACEAVAIL:
/*
* XXXMRG What is this? I think it's:
*
* Ensure that we have allocated backing-store
* for these pages.
*
* This is going to require changes to the page daemon,
* as it will free swap space allocated to pages in core.
* There's also what to do for device/file/anonymous memory.
*/
return EINVAL;
default:
return EINVAL;
}
return error;
}
/*
* sys_mlock: memory lock
*/
int
sys_mlock(struct proc *p, void *v, register_t *retval)
{
struct sys_mlock_args /* {
syscallarg(const void *) addr;
syscallarg(size_t) len;
} */ *uap = v;
vaddr_t addr;
vsize_t size, pageoff;
int error;
/* extract syscall args from uap */
addr = (vaddr_t)SCARG(uap, addr);
size = (vsize_t)SCARG(uap, len);
/* align address to a page boundary and adjust size accordingly */
ALIGN_ADDR(addr, size, pageoff);
if (addr > SIZE_MAX - size)
return EINVAL; /* disallow wrap-around. */
if (atop(size) + uvmexp.wired > uvmexp.wiredmax)
return EAGAIN;
#ifdef pmap_wired_count
if (size + ptoa(pmap_wired_count(vm_map_pmap(&p->p_vmspace->vm_map))) >
lim_cur(RLIMIT_MEMLOCK))
return EAGAIN;
#else
if ((error = suser(p)) != 0)
return error;
#endif
error = uvm_map_pageable(&p->p_vmspace->vm_map, addr, addr+size, FALSE,
0);
return error == 0 ? 0 : ENOMEM;
}
/*
* sys_munlock: unlock wired pages
*/
int
sys_munlock(struct proc *p, void *v, register_t *retval)
{
struct sys_munlock_args /* {
syscallarg(const void *) addr;
syscallarg(size_t) len;
} */ *uap = v;
vaddr_t addr;
vsize_t size, pageoff;
int error;
/* extract syscall args from uap */
addr = (vaddr_t)SCARG(uap, addr);
size = (vsize_t)SCARG(uap, len);
/* align address to a page boundary, and adjust size accordingly */
ALIGN_ADDR(addr, size, pageoff);
if (addr > SIZE_MAX - size)
return EINVAL; /* disallow wrap-around. */
#ifndef pmap_wired_count
if ((error = suser(p)) != 0)
return error;
#endif
error = uvm_map_pageable(&p->p_vmspace->vm_map, addr, addr+size, TRUE,
0);
return error == 0 ? 0 : ENOMEM;
}
/*
* sys_mlockall: lock all pages mapped into an address space.
*/
int
sys_mlockall(struct proc *p, void *v, register_t *retval)
{
struct sys_mlockall_args /* {
syscallarg(int) flags;
} */ *uap = v;
int error, flags;
flags = SCARG(uap, flags);
if (flags == 0 ||
(flags & ~(MCL_CURRENT|MCL_FUTURE)) != 0)
return EINVAL;
#ifndef pmap_wired_count
if ((error = suser(p)) != 0)
return error;
#endif
error = uvm_map_pageable_all(&p->p_vmspace->vm_map, flags,
lim_cur(RLIMIT_MEMLOCK));
if (error != 0 && error != ENOMEM)
return EAGAIN;
return error;
}
/*
* sys_munlockall: unlock all pages mapped into an address space.
*/
int
sys_munlockall(struct proc *p, void *v, register_t *retval)
{
(void) uvm_map_pageable_all(&p->p_vmspace->vm_map, 0, 0);
return 0;
}
/*
* common code for mmapanon and mmapfile to lock a mmaping
*/
int
uvm_mmaplock(vm_map_t map, vaddr_t *addr, vsize_t size, vm_prot_t prot,
vsize_t locklimit)
{
int error;
/*
* POSIX 1003.1b -- if our address space was configured
* to lock all future mappings, wire the one we just made.
*/
if (prot == PROT_NONE) {
/*
* No more work to do in this case.
*/
return 0;
}
vm_map_lock(map);
if (map->flags & VM_MAP_WIREFUTURE) {
KERNEL_LOCK();
if ((atop(size) + uvmexp.wired) > uvmexp.wiredmax
#ifdef pmap_wired_count
|| (locklimit != 0 && (size +
ptoa(pmap_wired_count(vm_map_pmap(map)))) >
locklimit)
#endif
) {
error = ENOMEM;
vm_map_unlock(map);
/* unmap the region! */
uvm_unmap(map, *addr, *addr + size);
KERNEL_UNLOCK();
return error;
}
/*
* uvm_map_pageable() always returns the map
* unlocked.
*/
error = uvm_map_pageable(map, *addr, *addr + size,
FALSE, UVM_LK_ENTER);
if (error != 0) {
/* unmap the region! */
uvm_unmap(map, *addr, *addr + size);
KERNEL_UNLOCK();
return error;
}
KERNEL_UNLOCK();
return 0;
}
vm_map_unlock(map);
return 0;
}
/*
* uvm_mmapanon: internal version of mmap for anons
*
* - used by sys_mmap
*/
int
uvm_mmapanon(vm_map_t map, vaddr_t *addr, vsize_t size, vm_prot_t prot,
vm_prot_t maxprot, int flags, vsize_t locklimit, struct proc *p)
{
int error;
int advice = MADV_NORMAL;
unsigned int uvmflag = 0;
vsize_t align = 0; /* userland page size */
/*
* for non-fixed mappings, round off the suggested address.
* for fixed mappings, check alignment and zap old mappings.
*/
if ((flags & MAP_FIXED) == 0) {
*addr = round_page(*addr); /* round */
} else {
if (*addr & PAGE_MASK)
return EINVAL;
uvmflag |= UVM_FLAG_FIXED;
if ((flags & __MAP_NOREPLACE) == 0)
uvmflag |= UVM_FLAG_UNMAP;
}
if ((flags & MAP_FIXED) == 0 && size >= __LDPGSZ)
align = __LDPGSZ;
if ((flags & MAP_SHARED) == 0)
/* XXX: defer amap create */
uvmflag |= UVM_FLAG_COPYONW;
else
/* shared: create amap now */
uvmflag |= UVM_FLAG_OVERLAY;
if (flags & MAP_STACK)
uvmflag |= UVM_FLAG_STACK;
if (flags & MAP_CONCEAL)
uvmflag |= UVM_FLAG_CONCEAL;
/* set up mapping flags */
uvmflag = UVM_MAPFLAG(prot, maxprot,
(flags & MAP_SHARED) ? MAP_INHERIT_SHARE : MAP_INHERIT_COPY,
advice, uvmflag);
error = uvm_mapanon(map, addr, size, align, uvmflag);
if (error == 0)
error = uvm_mmaplock(map, addr, size, prot, locklimit);
return error;
}
/*
* uvm_mmapfile: internal version of mmap for non-anons
*
* - used by sys_mmap
* - caller must page-align the file offset
*/
int
uvm_mmapfile(vm_map_t map, vaddr_t *addr, vsize_t size, vm_prot_t prot,
vm_prot_t maxprot, int flags, struct vnode *vp, voff_t foff,
vsize_t locklimit, struct proc *p)
{
struct uvm_object *uobj;
int error;
int advice = MADV_NORMAL;
unsigned int uvmflag = 0;
vsize_t align = 0; /* userland page size */
/*
* for non-fixed mappings, round off the suggested address.
* for fixed mappings, check alignment and zap old mappings.
*/
if ((flags & MAP_FIXED) == 0) {
*addr = round_page(*addr); /* round */
} else {
if (*addr & PAGE_MASK)
return EINVAL;
uvmflag |= UVM_FLAG_FIXED;
if ((flags & __MAP_NOREPLACE) == 0)
uvmflag |= UVM_FLAG_UNMAP;
}
/*
* attach to underlying vm object.
*/
if (vp->v_type != VCHR) {
uobj = uvn_attach(vp, (flags & MAP_SHARED) ?
maxprot : (maxprot & ~PROT_WRITE));
/*
* XXXCDC: hack from old code
* don't allow vnodes which have been mapped
* shared-writeable to persist [forces them to be
* flushed out when last reference goes].
* XXXCDC: interesting side effect: avoids a bug.
* note that in WRITE [ufs_readwrite.c] that we
* allocate buffer, uncache, and then do the write.
* the problem with this is that if the uncache causes
* VM data to be flushed to the same area of the file
* we are writing to... in that case we've got the
* buffer locked and our process goes to sleep forever.
*
* XXXCDC: checking maxprot protects us from the
* "persistbug" program but this is not a long term
* solution.
*
* XXXCDC: we don't bother calling uncache with the vp
* VOP_LOCKed since we know that we are already
* holding a valid reference to the uvn (from the
* uvn_attach above), and thus it is impossible for
* the uncache to kill the uvn and trigger I/O.
*/
if (flags & MAP_SHARED) {
if ((prot & PROT_WRITE) ||
(maxprot & PROT_WRITE)) {
uvm_vnp_uncache(vp);
}
}
} else {
uobj = udv_attach(vp->v_rdev,
(flags & MAP_SHARED) ? maxprot :
(maxprot & ~PROT_WRITE), foff, size);
/*
* XXX Some devices don't like to be mapped with
* XXX PROT_EXEC, but we don't really have a
* XXX better way of handling this, right now
*/
if (uobj == NULL && (prot & PROT_EXEC) == 0) {
maxprot &= ~PROT_EXEC;
uobj = udv_attach(vp->v_rdev,
(flags & MAP_SHARED) ? maxprot :
(maxprot & ~PROT_WRITE), foff, size);
}
advice = MADV_RANDOM;
}
if (uobj == NULL)
return vp->v_type == VREG ? ENOMEM : EINVAL;
if ((flags & MAP_SHARED) == 0)
uvmflag |= UVM_FLAG_COPYONW;
if (flags & __MAP_NOFAULT)
uvmflag |= (UVM_FLAG_NOFAULT | UVM_FLAG_OVERLAY);
if (flags & MAP_STACK)
uvmflag |= UVM_FLAG_STACK;
if (flags & MAP_CONCEAL)
uvmflag |= UVM_FLAG_CONCEAL;
/* set up mapping flags */
uvmflag = UVM_MAPFLAG(prot, maxprot,
(flags & MAP_SHARED) ? MAP_INHERIT_SHARE : MAP_INHERIT_COPY,
advice, uvmflag);
error = uvm_map(map, addr, size, uobj, foff, align, uvmflag);
if (error == 0)
return uvm_mmaplock(map, addr, size, prot, locklimit);
/* errors: first detach from the uobj, if any. */
if (uobj)
uobj->pgops->pgo_detach(uobj);
return error;
}
int
sys_kbind(struct proc *p, void *v, register_t *retval)
{
struct sys_kbind_args /* {
syscallarg(const struct __kbind *) param;
syscallarg(size_t) psize;
syscallarg(uint64_t) proc_cookie;
} */ *uap = v;
const struct __kbind *paramp;
union {
struct __kbind uk[KBIND_BLOCK_MAX];
char upad[KBIND_BLOCK_MAX * sizeof(*paramp) + KBIND_DATA_MAX];
} param;
struct uvm_map_deadq dead_entries;
struct process *pr = p->p_p;
const char *data;
vaddr_t baseva, last_baseva, endva, pageoffset, kva;
size_t psize, s;
u_long pc;
int count, i, extra;
int error, sigill = 0;
/*
* extract syscall args from uap
*/
paramp = SCARG(uap, param);
psize = SCARG(uap, psize);
/*
* If paramp is NULL and we're uninitialized, disable the syscall
* for the process. Raise SIGILL if paramp is NULL and we're
* already initialized.
*
* If paramp is non-NULL and we're uninitialized, do initialization.
* Otherwise, do security checks and raise SIGILL on failure.
*/
pc = PROC_PC(p);
mtx_enter(&pr->ps_mtx);
if (paramp == NULL) {
/* ld.so disables kbind() when lazy binding is disabled */
if (pr->ps_kbind_addr == 0)
pr->ps_kbind_addr = BOGO_PC;
/* pre-7.3 static binaries disable kbind */
/* XXX delete check in 2026 */
else if (pr->ps_kbind_addr != BOGO_PC)
sigill = 1;
} else if (pr->ps_kbind_addr == 0) {
pr->ps_kbind_addr = pc;
pr->ps_kbind_cookie = SCARG(uap, proc_cookie);
} else if (pc != pr->ps_kbind_addr || pc == BOGO_PC ||
pr->ps_kbind_cookie != SCARG(uap, proc_cookie)) {
sigill = 1;
}
mtx_leave(&pr->ps_mtx);
/* Raise SIGILL if something is off. */
if (sigill) {
KERNEL_LOCK();
sigexit(p, SIGILL);
/* NOTREACHED */
KERNEL_UNLOCK();
}
/* We're done if we were disabling the syscall. */
if (paramp == NULL)
return 0;
if (psize < sizeof(struct __kbind) || psize > sizeof(param))
return EINVAL;
if ((error = copyin(paramp, ¶m, psize)))
return error;
/*
* The param argument points to an array of __kbind structures
* followed by the corresponding new data areas for them. Verify
* that the sizes in the __kbind structures add up to the total
* size and find the start of the new area.
*/
paramp = ¶m.uk[0];
s = psize;
for (count = 0; s > 0 && count < KBIND_BLOCK_MAX; count++) {
if (s < sizeof(*paramp))
return EINVAL;
s -= sizeof(*paramp);
baseva = (vaddr_t)paramp[count].kb_addr;
endva = baseva + paramp[count].kb_size - 1;
if (paramp[count].kb_addr == NULL ||
paramp[count].kb_size == 0 ||
paramp[count].kb_size > KBIND_DATA_MAX ||
baseva >= VM_MAXUSER_ADDRESS ||
endva >= VM_MAXUSER_ADDRESS ||
s < paramp[count].kb_size)
return EINVAL;
s -= paramp[count].kb_size;
}
if (s > 0)
return EINVAL;
data = (const char *)¶mp[count];
/* all looks good, so do the bindings */
last_baseva = VM_MAXUSER_ADDRESS;
kva = 0;
TAILQ_INIT(&dead_entries);
for (i = 0; i < count; i++) {
baseva = (vaddr_t)paramp[i].kb_addr;
s = paramp[i].kb_size;
pageoffset = baseva & PAGE_MASK;
baseva = trunc_page(baseva);
/* hppa at least runs PLT entries over page edge */
extra = (pageoffset + s) & PAGE_MASK;
if (extra > pageoffset)
extra = 0;
else
s -= extra;
redo:
/* make sure the desired page is mapped into kernel_map */
if (baseva != last_baseva) {
if (kva != 0) {
vm_map_lock(kernel_map);
uvm_unmap_remove(kernel_map, kva,
kva+PAGE_SIZE, &dead_entries,
FALSE, TRUE, FALSE); /* XXX */
vm_map_unlock(kernel_map);
kva = 0;
}
if ((error = uvm_map_extract(&p->p_vmspace->vm_map,
baseva, PAGE_SIZE, &kva, UVM_EXTRACT_FIXPROT)))
break;
last_baseva = baseva;
}
/* do the update */
if ((error = kcopy(data, (char *)kva + pageoffset, s)))
break;
data += s;
if (extra > 0) {
baseva += PAGE_SIZE;
s = extra;
pageoffset = 0;
extra = 0;
goto redo;
}
}
if (kva != 0) {
vm_map_lock(kernel_map);
uvm_unmap_remove(kernel_map, kva, kva+PAGE_SIZE,
&dead_entries, FALSE, TRUE, FALSE); /* XXX */
vm_map_unlock(kernel_map);
}
uvm_unmap_detach(&dead_entries, AMAP_REFALL);
return error;
}
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