/* * Copyright (c) 1988 University of Utah. * Copyright (c) 1991, 1993 * The Regents of the University of California. 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 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 8.4 (Berkeley) 1/12/94 * $Id: vm_mmap.c,v 1.15 1995/03/19 14:29:25 davidg Exp $ */ /* * Mapped file (mmap) interface to VM */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #ifdef DEBUG int mmapdebug = 0; #define MDB_FOLLOW 0x01 #define MDB_SYNC 0x02 #define MDB_MAPIT 0x04 #endif void pmap_object_init_pt(); struct sbrk_args { int incr; }; /* ARGSUSED */ int sbrk(p, uap, retval) struct proc *p; struct sbrk_args *uap; int *retval; { /* Not yet implemented */ return (EOPNOTSUPP); } struct sstk_args { int incr; }; /* ARGSUSED */ int sstk(p, uap, retval) struct proc *p; struct sstk_args *uap; int *retval; { /* Not yet implemented */ return (EOPNOTSUPP); } #if defined(COMPAT_43) || defined(COMPAT_SUNOS) struct getpagesize_args { int dummy; }; /* ARGSUSED */ int ogetpagesize(p, uap, retval) struct proc *p; struct getpagesize_args *uap; int *retval; { *retval = PAGE_SIZE; return (0); } #endif /* COMPAT_43 || COMPAT_SUNOS */ struct mmap_args { caddr_t addr; size_t len; int prot; int flags; int fd; long pad; off_t pos; }; int mmap(p, uap, retval) struct proc *p; register struct mmap_args *uap; int *retval; { register struct filedesc *fdp = p->p_fd; register struct file *fp; struct vnode *vp; vm_offset_t addr; vm_size_t size; vm_prot_t prot, maxprot; caddr_t handle; int flags, error; prot = uap->prot & VM_PROT_ALL; flags = uap->flags; #ifdef DEBUG if (mmapdebug & MDB_FOLLOW) printf("mmap(%d): addr %x len %x pro %x flg %x fd %d pos %x\n", p->p_pid, uap->addr, uap->len, prot, flags, uap->fd, (vm_offset_t) uap->pos); #endif /* * Address (if FIXED) must be page aligned. Size is implicitly rounded * to a page boundary. */ addr = (vm_offset_t) uap->addr; if (((flags & MAP_FIXED) && (addr & PAGE_MASK)) || (ssize_t) uap->len < 0 || ((flags & MAP_ANON) && uap->fd != -1)) return (EINVAL); size = (vm_size_t) round_page(uap->len); /* * Check for illegal addresses. Watch out for address wrap... Note * that VM_*_ADDRESS are not constants due to casts (argh). */ if (flags & MAP_FIXED) { if (VM_MAXUSER_ADDRESS > 0 && addr + size > VM_MAXUSER_ADDRESS) return (EINVAL); #ifndef i386 if (VM_MIN_ADDRESS > 0 && addr < VM_MIN_ADDRESS) return (EINVAL); #endif if (addr + size < addr) return (EINVAL); } /* * XXX if no hint provided for a non-fixed mapping place it after the * end of the largest possible heap. * * There should really be a pmap call to determine a reasonable location. */ if (addr == 0 && (flags & MAP_FIXED) == 0) addr = round_page(p->p_vmspace->vm_daddr + MAXDSIZ); if (flags & MAP_ANON) { /* * Mapping blank space is trivial. */ handle = NULL; maxprot = VM_PROT_ALL; } else { /* * Mapping file, get fp for validation. Obtain vnode and make * sure it is of appropriate type. */ if (((unsigned) uap->fd) >= fdp->fd_nfiles || (fp = fdp->fd_ofiles[uap->fd]) == NULL) return (EBADF); if (fp->f_type != DTYPE_VNODE) return (EINVAL); vp = (struct vnode *) fp->f_data; if (vp->v_type != VREG && vp->v_type != VCHR) return (EINVAL); /* * XXX hack to handle use of /dev/zero to map anon memory (ala * SunOS). */ if (vp->v_type == VCHR && iszerodev(vp->v_rdev)) { handle = NULL; maxprot = VM_PROT_ALL; flags |= MAP_ANON; } else { /* * Ensure that file and memory protections are * compatible. Note that we only worry about * writability if mapping is shared; in this case, * current and max prot are dictated by the open file. * XXX use the vnode instead? Problem is: what * credentials do we use for determination? What if * proc does a setuid? */ maxprot = VM_PROT_EXECUTE; /* ??? */ if (fp->f_flag & FREAD) maxprot |= VM_PROT_READ; else if (prot & PROT_READ) return (EACCES); if (flags & MAP_SHARED) { if (fp->f_flag & FWRITE) maxprot |= VM_PROT_WRITE; else if (prot & PROT_WRITE) return (EACCES); } else maxprot |= VM_PROT_WRITE; handle = (caddr_t) vp; } } error = vm_mmap(&p->p_vmspace->vm_map, &addr, size, prot, maxprot, flags, handle, (vm_offset_t) uap->pos); if (error == 0) *retval = (int) addr; return (error); } #ifdef COMPAT_43 struct ommap_args { caddr_t addr; int len; int prot; int flags; int fd; long pos; }; int ommap(p, uap, retval) struct proc *p; register struct ommap_args *uap; int *retval; { struct mmap_args nargs; static const char cvtbsdprot[8] = { 0, PROT_EXEC, PROT_WRITE, PROT_EXEC | PROT_WRITE, PROT_READ, PROT_EXEC | PROT_READ, PROT_WRITE | PROT_READ, PROT_EXEC | PROT_WRITE | PROT_READ, }; #define OMAP_ANON 0x0002 #define OMAP_COPY 0x0020 #define OMAP_SHARED 0x0010 #define OMAP_FIXED 0x0100 #define OMAP_INHERIT 0x0800 nargs.addr = uap->addr; nargs.len = uap->len; nargs.prot = cvtbsdprot[uap->prot & 0x7]; nargs.flags = 0; if (uap->flags & OMAP_ANON) nargs.flags |= MAP_ANON; if (uap->flags & OMAP_COPY) nargs.flags |= MAP_COPY; if (uap->flags & OMAP_SHARED) nargs.flags |= MAP_SHARED; else nargs.flags |= MAP_PRIVATE; if (uap->flags & OMAP_FIXED) nargs.flags |= MAP_FIXED; if (uap->flags & OMAP_INHERIT) nargs.flags |= MAP_INHERIT; nargs.fd = uap->fd; nargs.pos = uap->pos; return (mmap(p, &nargs, retval)); } #endif /* COMPAT_43 */ struct msync_args { caddr_t addr; int len; }; int msync(p, uap, retval) struct proc *p; struct msync_args *uap; int *retval; { vm_offset_t addr; vm_size_t size; vm_map_t map; int rv; boolean_t syncio, invalidate; #ifdef DEBUG if (mmapdebug & (MDB_FOLLOW | MDB_SYNC)) printf("msync(%d): addr %x len %x\n", p->p_pid, uap->addr, uap->len); #endif if (((int) uap->addr & PAGE_MASK) || uap->addr + uap->len < uap->addr) return (EINVAL); map = &p->p_vmspace->vm_map; addr = (vm_offset_t) uap->addr; size = (vm_size_t) uap->len; /* * 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 = vm_map_lookup_entry(map, addr, &entry); vm_map_unlock_read(map); if (rv == FALSE) return (EINVAL); addr = entry->start; size = entry->end - entry->start; } #ifdef DEBUG if (mmapdebug & MDB_SYNC) printf("msync: cleaning/flushing address range [%x-%x)\n", addr, addr + size); #endif /* * Could pass this in as a third flag argument to implement Sun's * MS_ASYNC. */ syncio = TRUE; /* * XXX bummer, gotta flush all cached pages to ensure consistency with * the file system cache. Otherwise, we could pass this in to * implement Sun's MS_INVALIDATE. */ invalidate = TRUE; /* * Clean the pages and interpret the return value. */ rv = vm_map_clean(map, addr, addr + size, syncio, invalidate); switch (rv) { case KERN_SUCCESS: break; case KERN_INVALID_ADDRESS: return (EINVAL); /* Sun returns ENOMEM? */ case KERN_FAILURE: return (EIO); default: return (EINVAL); } return (0); } struct munmap_args { caddr_t addr; int len; }; int munmap(p, uap, retval) register struct proc *p; register struct munmap_args *uap; int *retval; { vm_offset_t addr; vm_size_t size; vm_map_t map; #ifdef DEBUG if (mmapdebug & MDB_FOLLOW) printf("munmap(%d): addr %x len %x\n", p->p_pid, uap->addr, uap->len); #endif addr = (vm_offset_t) uap->addr; if ((addr & PAGE_MASK) || uap->len < 0) return (EINVAL); size = (vm_size_t) round_page(uap->len); 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); #ifndef i386 if (VM_MIN_ADDRESS > 0 && addr < VM_MIN_ADDRESS) return (EINVAL); #endif if (addr + size < addr) return (EINVAL); map = &p->p_vmspace->vm_map; /* * Make sure entire range is allocated. */ if (!vm_map_check_protection(map, addr, addr + size, VM_PROT_NONE)) return (EINVAL); /* returns nothing but KERN_SUCCESS anyway */ (void) vm_map_remove(map, addr, addr + size); return (0); } void munmapfd(p, fd) struct proc *p; int fd; { #ifdef DEBUG if (mmapdebug & MDB_FOLLOW) printf("munmapfd(%d): fd %d\n", p->p_pid, fd); #endif /* * XXX should unmap any regions mapped to this file */ p->p_fd->fd_ofileflags[fd] &= ~UF_MAPPED; } struct mprotect_args { caddr_t addr; int len; int prot; }; int mprotect(p, uap, retval) struct proc *p; struct mprotect_args *uap; int *retval; { vm_offset_t addr; vm_size_t size; register vm_prot_t prot; #ifdef DEBUG if (mmapdebug & MDB_FOLLOW) printf("mprotect(%d): addr %x len %x prot %d\n", p->p_pid, uap->addr, uap->len, uap->prot); #endif addr = (vm_offset_t) uap->addr; if ((addr & PAGE_MASK) || uap->len < 0) return (EINVAL); size = (vm_size_t) uap->len; prot = uap->prot & VM_PROT_ALL; switch (vm_map_protect(&p->p_vmspace->vm_map, addr, addr + size, prot, FALSE)) { case KERN_SUCCESS: return (0); case KERN_PROTECTION_FAILURE: return (EACCES); } return (EINVAL); } struct madvise_args { caddr_t addr; int len; int behav; }; /* ARGSUSED */ int madvise(p, uap, retval) struct proc *p; struct madvise_args *uap; int *retval; { /* Not yet implemented */ return (EOPNOTSUPP); } struct mincore_args { caddr_t addr; int len; char *vec; }; /* ARGSUSED */ int mincore(p, uap, retval) struct proc *p; struct mincore_args *uap; int *retval; { /* Not yet implemented */ return (EOPNOTSUPP); } struct mlock_args { caddr_t addr; size_t len; }; int mlock(p, uap, retval) struct proc *p; struct mlock_args *uap; int *retval; { vm_offset_t addr; vm_size_t size; int error; #ifdef DEBUG if (mmapdebug & MDB_FOLLOW) printf("mlock(%d): addr %x len %x\n", p->p_pid, uap->addr, uap->len); #endif addr = (vm_offset_t) uap->addr; if ((addr & PAGE_MASK) || uap->addr + uap->len < uap->addr) return (EINVAL); size = round_page((vm_size_t) uap->len); if (atop(size) + cnt.v_wire_count > vm_page_max_wired) return (EAGAIN); #ifdef pmap_wired_count if (size + ptoa(pmap_wired_count(vm_map_pmap(&p->p_vmspace->vm_map))) > p->p_rlimit[RLIMIT_MEMLOCK].rlim_cur) return (EAGAIN); #else error = suser(p->p_ucred, &p->p_acflag); if (error) return (error); #endif error = vm_map_pageable(&p->p_vmspace->vm_map, addr, addr + size, FALSE); return (error == KERN_SUCCESS ? 0 : ENOMEM); } struct munlock_args { caddr_t addr; size_t len; }; int munlock(p, uap, retval) struct proc *p; struct munlock_args *uap; int *retval; { vm_offset_t addr; vm_size_t size; int error; #ifdef DEBUG if (mmapdebug & MDB_FOLLOW) printf("munlock(%d): addr %x len %x\n", p->p_pid, uap->addr, uap->len); #endif addr = (vm_offset_t) uap->addr; if ((addr & PAGE_MASK) || uap->addr + uap->len < uap->addr) return (EINVAL); #ifndef pmap_wired_count error = suser(p->p_ucred, &p->p_acflag); if (error) return (error); #endif size = round_page((vm_size_t) uap->len); error = vm_map_pageable(&p->p_vmspace->vm_map, addr, addr + size, TRUE); return (error == KERN_SUCCESS ? 0 : ENOMEM); } /* * Internal version of mmap. * Currently used by mmap, exec, and sys5 shared memory. * Handle is either a vnode pointer or NULL for MAP_ANON. */ int vm_mmap(map, addr, size, prot, maxprot, flags, handle, foff) register vm_map_t map; register vm_offset_t *addr; register vm_size_t size; vm_prot_t prot, maxprot; register int flags; caddr_t handle; /* XXX should be vp */ vm_offset_t foff; { register vm_pager_t pager; boolean_t fitit; vm_object_t object; struct vnode *vp = NULL; int type; int rv = KERN_SUCCESS; if (size == 0) return (0); size = round_page(size); if ((flags & MAP_FIXED) == 0) { fitit = TRUE; *addr = round_page(*addr); } else { if (*addr != trunc_page(*addr)) return (EINVAL); fitit = FALSE; (void) vm_map_remove(map, *addr, *addr + size); } /* * Lookup/allocate pager. All except an unnamed anonymous lookup gain * a reference to ensure continued existance of the object. (XXX the * exception is to appease the pageout daemon) */ if (flags & MAP_ANON) type = PG_DFLT; else { vp = (struct vnode *) handle; if (vp->v_type == VCHR) { type = PG_DEVICE; handle = (caddr_t) vp->v_rdev; } else type = PG_VNODE; } pager = vm_pager_allocate(type, handle, size, prot, foff); if (pager == NULL) return (type == PG_DEVICE ? EINVAL : ENOMEM); /* * Guarantee that the pager has an object. */ object = vm_object_lookup(pager); if (object == NULL) { if (handle != NULL) panic("vm_mmap: pager didn't allocate an object (and should have)"); /* * Should only happen for unnamed anonymous regions. */ object = vm_object_allocate(size); object->pager = pager; } else { /* * Lose vm_object_lookup() reference. Retain reference * gained by vm_pager_allocate(). */ vm_object_deallocate(object); } /* * At this point, our actions above have gained a total of * one reference to the object, and we have a pager. */ /* * Anonymous memory, shared file, or character special file. */ if ((flags & (MAP_ANON|MAP_SHARED)) || (type == PG_DEVICE)) { rv = vm_map_find(map, object, foff, addr, size, fitit); if (rv != KERN_SUCCESS) { /* * Lose the object reference. This will also destroy * the pager if there are no other references. */ vm_object_deallocate(object); goto out; } } /* * mmap a COW regular file */ else { vm_map_t tmap; vm_offset_t off; vm_map_entry_t entry; if (flags & MAP_COPY) { /* locate and allocate the target address space */ rv = vm_map_find(map, NULL, 0, addr, size, fitit); if (rv != KERN_SUCCESS) { vm_object_deallocate(object); goto out; } off = VM_MIN_ADDRESS; tmap = vm_map_create(NULL, off, off + size, TRUE); rv = vm_map_find(tmap, object, foff, &off, size, FALSE); if (rv != KERN_SUCCESS) { /* * Deallocate and delete the temporary map. * Note that since the object insertion * above has failed, the vm_map_deallocate * doesn't lose the object reference - we * must do it explicitly. */ vm_object_deallocate(object); vm_map_deallocate(tmap); goto out; } rv = vm_map_copy(map, tmap, *addr, size, off, FALSE, FALSE); /* * Deallocate temporary map. XXX - depending * on events, this may leave the object with * no net gain in reference count! ...this * needs to be looked at! */ vm_map_deallocate(tmap); if (rv != KERN_SUCCESS) goto out; } else { vm_object_t user_object; /* * Create a new object and make the original object * the backing object. NOTE: the object reference gained * above is now changed into the reference held by * user_object. Since we don't map 'object', we want * only this one reference. */ user_object = vm_object_allocate( size); user_object->shadow = object; TAILQ_INSERT_TAIL(&object->reverse_shadow_head, user_object, reverse_shadow_list); rv = vm_map_find(map, user_object, foff, addr, size, fitit); if( rv != KERN_SUCCESS) { vm_object_deallocate(user_object); goto out; } /* * this is a consistancy check, gets the map entry, and should * never fail */ if (!vm_map_lookup_entry(map, *addr, &entry)) { panic("vm_mmap: missing map entry!!!"); } entry->copy_on_write = TRUE; } /* * set pages COW and protect for read access only */ vm_object_pmap_copy(object, foff, foff + size); } /* * "Pre-fault" resident pages. */ if ((type == PG_VNODE) && (map->pmap != NULL)) { pmap_object_init_pt(map->pmap, *addr, object, foff, size); } /* * Correct protection (default is VM_PROT_ALL). If maxprot is * different than prot, we must set both explicitly. */ rv = KERN_SUCCESS; if (maxprot != VM_PROT_ALL) rv = vm_map_protect(map, *addr, *addr + size, maxprot, TRUE); if (rv == KERN_SUCCESS && prot != maxprot) rv = vm_map_protect(map, *addr, *addr + size, prot, FALSE); if (rv != KERN_SUCCESS) { (void) vm_map_remove(map, *addr, *addr + size); goto out; } /* * Shared memory is also shared with children. */ if (flags & MAP_SHARED) { rv = vm_map_inherit(map, *addr, *addr + size, VM_INHERIT_SHARE); if (rv != KERN_SUCCESS) { (void) vm_map_remove(map, *addr, *addr + size); goto out; } } out: #ifdef DEBUG if (mmapdebug & MDB_MAPIT) printf("vm_mmap: rv %d\n", rv); #endif switch (rv) { case KERN_SUCCESS: return (0); case KERN_INVALID_ADDRESS: case KERN_NO_SPACE: return (ENOMEM); case KERN_PROTECTION_FAILURE: return (EACCES); default: return (EINVAL); } }