NetBSD/sys/uvm/uvm_mmap.c

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/* $NetBSD: uvm_mmap.c,v 1.12 1998/08/13 02:11:02 eeh Exp $ */
/*
* XXXCDC: "ROUGH DRAFT" QUALITY UVM PRE-RELEASE FILE!
* >>>USE AT YOUR OWN RISK, WORK IS NOT FINISHED<<<
*/
/*
* 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. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the Charles D. Cranor,
* Washington University, University of California, Berkeley and
* its contributors.
* 4. 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
1998-02-07 14:07:38 +03:00
* 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/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/stat.h>
#include <miscfs/specfs/specdev.h>
#include <vm/vm.h>
#include <vm/vm_page.h>
#include <vm/vm_kern.h>
#include <sys/syscallargs.h>
#include <uvm/uvm.h>
#include <uvm/uvm_device.h>
#include <uvm/uvm_vnode.h>
/*
* unimplemented VM system calls:
*/
/*
* sys_sbrk: sbrk system call.
*/
/* ARGSUSED */
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int
sys_sbrk(p, v, retval)
struct proc *p;
void *v;
register_t *retval;
{
#if 0
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struct sys_sbrk_args /* {
syscallarg(int) incr;
} */ *uap = v;
#endif
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return (EOPNOTSUPP);
}
/*
* sys_sstk: sstk system call.
*/
/* ARGSUSED */
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int
sys_sstk(p, v, retval)
struct proc *p;
void *v;
register_t *retval;
{
#if 0
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struct sys_sstk_args /* {
syscallarg(int) incr;
} */ *uap = v;
#endif
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return (EOPNOTSUPP);
}
/*
* sys_madvise: give advice about memory usage.
*/
/* ARGSUSED */
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int
sys_madvise(p, v, retval)
struct proc *p;
void *v;
register_t *retval;
{
#if 0
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struct sys_madvise_args /* {
syscallarg(caddr_t) addr;
syscallarg(size_t) len;
syscallarg(int) behav;
} */ *uap = v;
#endif
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return (EOPNOTSUPP);
}
/*
* sys_mincore: determine if pages are in core or not.
*/
/* ARGSUSED */
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int
sys_mincore(p, v, retval)
struct proc *p;
void *v;
register_t *retval;
{
#if 0
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struct sys_mincore_args /* {
syscallarg(caddr_t) addr;
syscallarg(size_t) len;
syscallarg(char *) vec;
} */ *uap = v;
#endif
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return (EOPNOTSUPP);
}
#if 0
/*
* munmapfd: unmap file descriptor
*
* XXX: is this acutally a useful function? could it be useful?
*/
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void
munmapfd(p, fd)
struct proc *p;
int fd;
{
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/*
* XXX should vm_deallocate any regions mapped to this file
*/
p->p_fd->fd_ofileflags[fd] &= ~UF_MAPPED;
}
#endif
/*
* sys_mmap: mmap system call.
*
* => file offest 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.
*/
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int
sys_mmap(p, v, retval)
struct proc *p;
void *v;
register_t *retval;
{
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register struct sys_mmap_args /* {
syscallarg(caddr_t) addr;
syscallarg(size_t) len;
syscallarg(int) prot;
syscallarg(int) flags;
syscallarg(int) fd;
syscallarg(long) pad;
syscallarg(off_t) pos;
} */ *uap = v;
vaddr_t addr;
struct vattr va;
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off_t pos;
vsize_t size, pageoff;
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vm_prot_t prot, maxprot;
int flags, fd;
vaddr_t vm_min_address = VM_MIN_ADDRESS;
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register struct filedesc *fdp = p->p_fd;
register struct file *fp;
struct vnode *vp;
caddr_t handle;
int error;
/*
* first, extract syscall args from the uap.
*/
addr = (vaddr_t) SCARG(uap, addr);
size = (vsize_t) SCARG(uap, len);
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prot = SCARG(uap, prot) & VM_PROT_ALL;
flags = SCARG(uap, flags);
fd = SCARG(uap, fd);
pos = SCARG(uap, pos);
/*
* make sure that the newsize fits within a vaddr_t
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* XXX: need to revise addressing data types
*/
if (pos + size > (vaddr_t)-PAGE_SIZE) {
#ifdef DEBUG
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printf("mmap: pos=%qx, size=%x too big\n", pos, (int)size);
#endif
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return (EINVAL);
}
/*
* align file position and save offset. adjust size.
*/
pageoff = (pos & PAGE_MASK);
pos -= pageoff;
size += pageoff; /* add offset */
size = (vsize_t) round_page(size); /* round up */
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if ((ssize_t) size < 0)
return (EINVAL); /* don't allow wrap */
/*
* now check (MAP_FIXED) or get (!MAP_FIXED) the "addr"
*/
if (flags & MAP_FIXED) {
/* ensure address and file offset are aligned properly */
addr -= pageoff;
if (addr & PAGE_MASK)
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);
if (addr > addr + size)
return (EINVAL); /* no wrapping! */
} else {
/*
* not fixed: make sure we skip over the largest possible heap.
* we will refine our guess later (e.g. to account for VAC, etc)
*/
if (addr < round_page(p->p_vmspace->vm_daddr + MAXDSIZ))
addr = round_page(p->p_vmspace->vm_daddr + MAXDSIZ);
}
/*
* check for file mappings (i.e. not anonymous) and verify file.
*/
if ((flags & MAP_ANON) == 0) {
if (fd < 0 || fd >= fdp->fd_nfiles)
return(EBADF); /* failed range check? */
fp = fdp->fd_ofiles[fd]; /* convert to file pointer */
if (fp == NULL)
return(EBADF);
if (fp->f_type != DTYPE_VNODE)
return (ENODEV); /* only mmap vnodes! */
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vp = (struct vnode *)fp->f_data; /* convert to vnode */
if (vp->v_type != VREG && vp->v_type != VCHR &&
vp->v_type != VBLK)
return (ENODEV); /* only REG/CHR/BLK support mmap */
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/* special case: catch SunOS style /dev/zero */
if (vp->v_type == VCHR && iszerodev(vp->v_rdev)) {
flags |= MAP_ANON;
goto is_anon;
}
/*
* Old programs may not select a specific sharing type, so
* default to an appropriate one.
*
* XXX: how does MAP_ANON fit in the picture?
*/
if ((flags & (MAP_SHARED|MAP_PRIVATE|MAP_COPY)) == 0) {
#if defined(DEBUG)
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printf("WARNING: defaulted mmap() share type to "
"%s (pid %d comm %s)\n", vp->v_type == VCHR ?
"MAP_SHARED" : "MAP_PRIVATE", p->p_pid,
p->p_comm);
#endif
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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) {
#if defined(DIAGNOSTIC)
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printf("WARNING: converted MAP_PRIVATE device mapping "
"to MAP_SHARED (pid %d comm %s)\n", p->p_pid,
p->p_comm);
#endif
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flags = (flags & ~MAP_PRIVATE) | MAP_SHARED;
}
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/*
* now check protection
*/
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maxprot = VM_PROT_EXECUTE;
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/* check read access */
if (fp->f_flag & FREAD)
maxprot |= VM_PROT_READ;
else if (prot & PROT_READ)
return (EACCES);
/* check write access, shared case first */
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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) {
if ((error =
VOP_GETATTR(vp, &va, p->p_ucred, p)))
return (error);
if ((va.va_flags & (IMMUTABLE|APPEND)) == 0)
maxprot |= VM_PROT_WRITE;
else if (prot & PROT_WRITE)
return (EPERM);
}
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else if (prot & PROT_WRITE)
return (EACCES);
} else {
/* MAP_PRIVATE mappings can always write to */
maxprot |= VM_PROT_WRITE;
}
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/*
* set handle to vnode
*/
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handle = (caddr_t)vp;
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} else { /* MAP_ANON case */
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if (fd != -1)
return (EINVAL);
is_anon: /* label for SunOS style /dev/zero */
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handle = NULL;
maxprot = VM_PROT_ALL;
pos = 0;
}
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/*
* now let kernel internal function uvm_mmap do the work.
*/
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error = uvm_mmap(&p->p_vmspace->vm_map, &addr, size, prot, maxprot,
flags, handle, pos);
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if (error == 0)
/* remember to add offset */
*retval = (register_t)(addr + pageoff);
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return (error);
}
/*
* sys___msync13: the msync system call (a front-end for flush)
*/
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int
sys___msync13(p, v, retval)
struct proc *p;
void *v;
register_t *retval;
{
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struct sys___msync13_args /* {
syscallarg(caddr_t) addr;
syscallarg(size_t) len;
syscallarg(int) flags;
} */ *uap = v;
vaddr_t addr;
vsize_t size, pageoff;
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vm_map_t map;
int rv, flags, uvmflags;
/*
* extract syscall args from the uap
*/
addr = (vaddr_t)SCARG(uap, addr);
size = (vsize_t)SCARG(uap, len);
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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);
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if ((flags & (MS_ASYNC | MS_SYNC)) == 0)
flags |= MS_SYNC;
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/*
* align the address to a page boundary, and adjust the size accordingly
*/
pageoff = (addr & PAGE_MASK);
addr -= pageoff;
size += pageoff;
size = (vsize_t) round_page(size);
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/* disallow wrap-around. */
if (addr + size < addr)
return (EINVAL);
/*
* get map
*/
map = &p->p_vmspace->vm_map;
/*
* XXXCDC: do we really need this semantic?
*
* XXX Gak! If size is zero we are supposed to sync "all modified
* pages with the region containing addr". Unfortunately, we
* don't really keep track of individual mmaps so we approximate
* by flushing the range of the map entry containing addr.
* This can be incorrect if the region splits or is coalesced
* with a neighbor.
*/
if (size == 0) {
vm_map_entry_t entry;
vm_map_lock_read(map);
rv = uvm_map_lookup_entry(map, addr, &entry);
if (rv == TRUE) {
addr = entry->start;
size = entry->end - entry->start;
}
vm_map_unlock_read(map);
if (rv == FALSE)
return (EINVAL);
}
/*
* translate MS_ flags into PGO_ flags
*/
uvmflags = (flags & MS_INVALIDATE) ? PGO_FREE : 0;
if (flags & MS_SYNC)
uvmflags |= PGO_SYNCIO;
else
uvmflags |= PGO_SYNCIO; /* XXXCDC: force sync for now! */
/*
* doit!
*/
rv = uvm_map_clean(map, addr, addr+size, uvmflags);
/*
* and return...
*/
switch (rv) {
case KERN_SUCCESS:
return(0);
case KERN_INVALID_ADDRESS:
return (ENOMEM);
case KERN_FAILURE:
return (EIO);
case KERN_PAGES_LOCKED: /* XXXCDC: uvm doesn't return this */
return (EBUSY);
default:
return (EINVAL);
}
/*NOTREACHED*/
}
/*
* sys_munmap: unmap a users memory
*/
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int
sys_munmap(p, v, retval)
register struct proc *p;
void *v;
register_t *retval;
{
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register struct sys_munmap_args /* {
syscallarg(caddr_t) addr;
syscallarg(size_t) len;
} */ *uap = v;
vaddr_t addr;
vsize_t size, pageoff;
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vm_map_t map;
vaddr_t vm_min_address = VM_MIN_ADDRESS;
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struct vm_map_entry *dead_entries;
/*
* get syscall args...
*/
addr = (vaddr_t) SCARG(uap, addr);
size = (vsize_t) SCARG(uap, len);
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/*
* align the address to a page boundary, and adjust the size accordingly
*/
pageoff = (addr & PAGE_MASK);
addr -= pageoff;
size += pageoff;
size = (vsize_t) round_page(size);
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if ((int)size < 0)
return (EINVAL);
if (size == 0)
return (0);
/*
* Check for illegal addresses. Watch out for address wrap...
* Note that VM_*_ADDRESS are not constants due to casts (argh).
*/
if (VM_MAXUSER_ADDRESS > 0 && addr + size > VM_MAXUSER_ADDRESS)
return (EINVAL);
if (vm_min_address > 0 && addr < vm_min_address)
return (EINVAL);
if (addr > addr + size)
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, VM_PROT_NONE)) {
vm_map_unlock(map);
return (EINVAL);
}
/*
* doit!
*/
(void) uvm_unmap_remove(map, addr, addr + size, 0, &dead_entries);
vm_map_unlock(map); /* and unlock */
if (dead_entries != NULL)
uvm_unmap_detach(dead_entries, 0);
return (0);
}
/*
* sys_mprotect: the mprotect system call
*/
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int
sys_mprotect(p, v, retval)
struct proc *p;
void *v;
register_t *retval;
{
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struct sys_mprotect_args /* {
syscallarg(caddr_t) addr;
syscallarg(int) len;
syscallarg(int) prot;
} */ *uap = v;
vaddr_t addr;
vsize_t size, pageoff;
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vm_prot_t prot;
int rv;
/*
* extract syscall args from uap
*/
addr = (vaddr_t)SCARG(uap, addr);
size = (vsize_t)SCARG(uap, len);
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prot = SCARG(uap, prot) & VM_PROT_ALL;
/*
* align the address to a page boundary, and adjust the size accordingly
*/
pageoff = (addr & PAGE_MASK);
addr -= pageoff;
size += pageoff;
size = (vsize_t) round_page(size);
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if ((int)size < 0)
return (EINVAL);
/*
* doit
*/
rv = uvm_map_protect(&p->p_vmspace->vm_map,
addr, addr+size, prot, FALSE);
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if (rv == KERN_SUCCESS)
return (0);
if (rv == KERN_PROTECTION_FAILURE)
return (EACCES);
return (EINVAL);
}
/*
* sys_minherit: the minherit system call
*/
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int
sys_minherit(p, v, retval)
struct proc *p;
void *v;
register_t *retval;
{
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struct sys_minherit_args /* {
syscallarg(caddr_t) addr;
syscallarg(int) len;
syscallarg(int) inherit;
} */ *uap = v;
vaddr_t addr;
vsize_t size, pageoff;
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register vm_inherit_t inherit;
addr = (vaddr_t)SCARG(uap, addr);
size = (vsize_t)SCARG(uap, len);
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inherit = SCARG(uap, inherit);
/*
* align the address to a page boundary, and adjust the size accordingly
*/
pageoff = (addr & PAGE_MASK);
addr -= pageoff;
size += pageoff;
size = (vsize_t) round_page(size);
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if ((int)size < 0)
return (EINVAL);
switch (uvm_map_inherit(&p->p_vmspace->vm_map, addr, addr+size,
inherit)) {
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case KERN_SUCCESS:
return (0);
case KERN_PROTECTION_FAILURE:
return (EACCES);
}
return (EINVAL);
}
/*
* sys_mlock: memory lock
*/
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int
sys_mlock(p, v, retval)
struct proc *p;
void *v;
register_t *retval;
{
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struct sys_mlock_args /* {
syscallarg(const void *) addr;
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syscallarg(size_t) len;
} */ *uap = v;
vaddr_t addr;
vsize_t size, pageoff;
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int error;
/*
* extract syscall args from uap
*/
addr = (vaddr_t)SCARG(uap, addr);
size = (vsize_t)SCARG(uap, len);
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/*
* align the address to a page boundary and adjust the size accordingly
*/
pageoff = (addr & PAGE_MASK);
addr -= pageoff;
size += pageoff;
size = (vsize_t) round_page(size);
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/* disallow wrap-around. */
if (addr + (int)size < addr)
return (EINVAL);
if (atop(size) + uvmexp.wired > uvmexp.wiredmax)
return (EAGAIN);
#ifdef pmap_wired_count
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if (size + ptoa(pmap_wired_count(vm_map_pmap(&p->p_vmspace->vm_map))) >
p->p_rlimit[RLIMIT_MEMLOCK].rlim_cur)
return (EAGAIN);
#else
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if ((error = suser(p->p_ucred, &p->p_acflag)) != 0)
return (error);
#endif
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error = uvm_map_pageable(&p->p_vmspace->vm_map, addr, addr+size, FALSE);
return (error == KERN_SUCCESS ? 0 : ENOMEM);
}
/*
* sys_munlock: unlock wired pages
*/
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int
sys_munlock(p, v, retval)
struct proc *p;
void *v;
register_t *retval;
{
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struct sys_munlock_args /* {
syscallarg(const void *) addr;
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syscallarg(size_t) len;
} */ *uap = v;
vaddr_t addr;
vsize_t size, pageoff;
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int error;
/*
* extract syscall args from uap
*/
addr = (vaddr_t)SCARG(uap, addr);
size = (vsize_t)SCARG(uap, len);
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/*
* align the address to a page boundary, and adjust the size accordingly
*/
pageoff = (addr & PAGE_MASK);
addr -= pageoff;
size += pageoff;
size = (vsize_t) round_page(size);
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/* disallow wrap-around. */
if (addr + (int)size < addr)
return (EINVAL);
#ifndef pmap_wired_count
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if ((error = suser(p->p_ucred, &p->p_acflag)) != 0)
return (error);
#endif
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error = uvm_map_pageable(&p->p_vmspace->vm_map, addr, addr+size, TRUE);
return (error == KERN_SUCCESS ? 0 : ENOMEM);
}
/*
* uvm_mmap: internal version of mmap
*
* - used by sys_mmap, exec, and sysv shm
* - handle is a vnode pointer or NULL for MAP_ANON (XXX: not true,
* sysv shm uses "named anonymous memory")
* - caller must page-align the file offset
*/
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int
uvm_mmap(map, addr, size, prot, maxprot, flags, handle, foff)
vm_map_t map;
vaddr_t *addr;
vsize_t size;
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vm_prot_t prot, maxprot;
int flags;
caddr_t handle; /* XXX: VNODE? */
vaddr_t foff;
{
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struct uvm_object *uobj;
struct vnode *vp;
int retval;
int advice = UVM_ADV_NORMAL;
uvm_flag_t uvmflag = 0;
/*
* check params
*/
if (size == 0)
return(0);
if (foff & PAGE_MASK)
return(EINVAL);
if ((prot & maxprot) != prot)
return(EINVAL);
/*
* 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;
(void) uvm_unmap(map, *addr, *addr + size, 0); /* zap! */
}
/*
* handle anon vs. non-anon mappings. for non-anon mappings attach
* to underlying vm object.
*/
if (flags & MAP_ANON) {
foff = UVM_UNKNOWN_OFFSET;
uobj = NULL;
if ((flags & MAP_SHARED) == 0)
/* XXX: defer amap create */
uvmflag |= UVM_FLAG_COPYONW;
else
/* shared: create amap now */
uvmflag |= UVM_FLAG_OVERLAY;
} else {
vp = (struct vnode *) handle; /* get vnode */
if (vp->v_type != VCHR) {
uobj = uvn_attach((void *) vp, (flags & MAP_SHARED) ?
maxprot : (maxprot & ~VM_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 & VM_PROT_WRITE) ||
(maxprot & VM_PROT_WRITE)) {
uvm_vnp_uncache(vp);
}
}
} else {
uobj = udv_attach((void *) &vp->v_rdev,
(flags & MAP_SHARED) ?
maxprot : (maxprot & ~VM_PROT_WRITE));
advice = UVM_ADV_RANDOM;
}
if (uobj == NULL)
return((vp->v_type == VREG) ? ENOMEM : EINVAL);
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if ((flags & MAP_SHARED) == 0)
uvmflag |= UVM_FLAG_COPYONW;
}
/*
* set up mapping flags
*/
uvmflag = UVM_MAPFLAG(prot, maxprot,
(flags & MAP_SHARED) ? UVM_INH_SHARE : UVM_INH_COPY,
advice, uvmflag);
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/*
* do it!
*/
retval = uvm_map(map, addr, size, uobj, foff, uvmflag);
if (retval == KERN_SUCCESS)
return(0);
/*
* errors: first detach from the uobj, if any.
*/
if (uobj)
uobj->pgops->pgo_detach(uobj);
switch (retval) {
case KERN_INVALID_ADDRESS:
case KERN_NO_SPACE:
return(ENOMEM);
case KERN_PROTECTION_FAILURE:
return(EACCES);
}
return(EINVAL);
}