/* $NetBSD: uvm_mmap.c,v 1.144 2012/01/27 19:48:41 para 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 __KERNEL_RCSID(0, "$NetBSD: uvm_mmap.c,v 1.144 2012/01/27 19:48:41 para Exp $"); #include "opt_compat_netbsd.h" #include "opt_pax.h" #include "veriexec.h" #include #include #include #include #include #include #include #include #include #include #if NVERIEXEC > 0 #include #endif /* NVERIEXEC > 0 */ #if defined(PAX_ASLR) || defined(PAX_MPROTECT) #include #endif /* PAX_ASLR || PAX_MPROTECT */ #include #include #include #include #ifndef COMPAT_ZERODEV #define COMPAT_ZERODEV(dev) (0) #endif static int range_test(vaddr_t addr, vsize_t size, bool ismmap) { vaddr_t vm_min_address = VM_MIN_ADDRESS; vaddr_t vm_max_address = VM_MAXUSER_ADDRESS; vaddr_t eaddr = addr + size; if (addr < vm_min_address) return EINVAL; if (eaddr > vm_max_address) return ismmap ? EFBIG : EINVAL; if (addr > eaddr) /* no wrapping! */ return ismmap ? EOVERFLOW : EINVAL; return 0; } /* * unimplemented VM system calls: */ /* * sys_sbrk: sbrk system call. */ /* ARGSUSED */ int sys_sbrk(struct lwp *l, const struct sys_sbrk_args *uap, register_t *retval) { /* { syscallarg(intptr_t) incr; } */ return (ENOSYS); } /* * sys_sstk: sstk system call. */ /* ARGSUSED */ int sys_sstk(struct lwp *l, const struct sys_sstk_args *uap, register_t *retval) { /* { syscallarg(int) incr; } */ return (ENOSYS); } /* * sys_mincore: determine if pages are in core or not. */ /* ARGSUSED */ int sys_mincore(struct lwp *l, const struct sys_mincore_args *uap, register_t *retval) { /* { syscallarg(void *) addr; syscallarg(size_t) len; syscallarg(char *) vec; } */ struct proc *p = l->l_proc; struct vm_page *pg; char *vec, pgi; struct uvm_object *uobj; struct vm_amap *amap; struct vm_anon *anon; struct vm_map_entry *entry; vaddr_t start, end, lim; struct vm_map *map; vsize_t len; int error = 0, npgs; map = &p->p_vmspace->vm_map; start = (vaddr_t)SCARG(uap, addr); len = SCARG(uap, len); vec = SCARG(uap, vec); if (start & PAGE_MASK) return (EINVAL); len = round_page(len); end = start + len; if (end <= start) return (EINVAL); /* * Lock down vec, so our returned status isn't outdated by * storing the status byte for a page. */ npgs = len >> PAGE_SHIFT; error = uvm_vslock(p->p_vmspace, vec, npgs, VM_PROT_WRITE); if (error) { return error; } vm_map_lock_read(map); if (uvm_map_lookup_entry(map, start, &entry) == false) { error = ENOMEM; goto out; } for (/* nothing */; entry != &map->header && entry->start < end; entry = entry->next) { KASSERT(!UVM_ET_ISSUBMAP(entry)); KASSERT(start >= entry->start); /* Make sure there are no holes. */ if (entry->end < end && (entry->next == &map->header || entry->next->start > entry->end)) { error = ENOMEM; goto out; } lim = end < entry->end ? end : entry->end; /* * Special case for objects with no "real" pages. Those * are always considered resident (mapped devices). */ if (UVM_ET_ISOBJ(entry)) { KASSERT(!UVM_OBJ_IS_KERN_OBJECT(entry->object.uvm_obj)); if (UVM_OBJ_IS_DEVICE(entry->object.uvm_obj)) { for (/* nothing */; start < lim; start += PAGE_SIZE, vec++) subyte(vec, 1); continue; } } amap = entry->aref.ar_amap; /* upper layer */ uobj = entry->object.uvm_obj; /* lower layer */ if (amap != NULL) amap_lock(amap); if (uobj != NULL) mutex_enter(uobj->vmobjlock); for (/* nothing */; start < lim; start += PAGE_SIZE, vec++) { pgi = 0; if (amap != NULL) { /* Check the upper layer first. */ anon = amap_lookup(&entry->aref, start - entry->start); /* Don't need to lock anon here. */ if (anon != NULL && anon->an_page != NULL) { /* * Anon has the page for this entry * offset. */ pgi = 1; } } if (uobj != NULL && pgi == 0) { /* Check the lower layer. */ pg = uvm_pagelookup(uobj, entry->offset + (start - entry->start)); if (pg != NULL) { /* * Object has the page for this entry * offset. */ pgi = 1; } } (void) subyte(vec, pgi); } if (uobj != NULL) mutex_exit(uobj->vmobjlock); if (amap != NULL) amap_unlock(amap); } out: vm_map_unlock_read(map); uvm_vsunlock(p->p_vmspace, SCARG(uap, vec), npgs); return (error); } /* * 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 lwp *l, const struct sys_mmap_args *uap, register_t *retval) { /* { syscallarg(void *) addr; syscallarg(size_t) len; syscallarg(int) prot; syscallarg(int) flags; syscallarg(int) fd; syscallarg(long) pad; syscallarg(off_t) pos; } */ struct proc *p = l->l_proc; vaddr_t addr; struct vattr va; off_t pos; vsize_t size, pageoff; vm_prot_t prot, maxprot; int flags, fd; vaddr_t defaddr; struct file *fp = NULL; struct vnode *vp; void *handle; int error; #ifdef PAX_ASLR vaddr_t orig_addr; #endif /* PAX_ASLR */ /* * first, extract syscall args from the uap. */ addr = (vaddr_t)SCARG(uap, addr); size = (vsize_t)SCARG(uap, len); prot = SCARG(uap, prot) & VM_PROT_ALL; flags = SCARG(uap, flags); fd = SCARG(uap, fd); pos = SCARG(uap, pos); #ifdef PAX_ASLR orig_addr = addr; #endif /* PAX_ASLR */ /* * Fixup the old deprecated MAP_COPY into MAP_PRIVATE, and * validate the flags. */ if (flags & MAP_COPY) flags = (flags & ~MAP_COPY) | MAP_PRIVATE; if ((flags & (MAP_SHARED|MAP_PRIVATE)) == (MAP_SHARED|MAP_PRIVATE)) 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 */ /* * 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); error = range_test(addr, size, true); if (error) return error; } else if (addr == 0 || !(flags & MAP_TRYFIXED)) { /* * not fixed: make sure we skip over the largest * possible heap for non-topdown mapping arrangements. * we will refine our guess later (e.g. to account for * VAC, etc) */ defaddr = p->p_emul->e_vm_default_addr(p, (vaddr_t)p->p_vmspace->vm_daddr, size); if (addr == 0 || !(p->p_vmspace->vm_map.flags & VM_MAP_TOPDOWN)) addr = MAX(addr, defaddr); else addr = MIN(addr, defaddr); } /* * check for file mappings (i.e. not anonymous) and verify file. */ if ((flags & MAP_ANON) == 0) { if ((fp = fd_getfile(fd)) == NULL) return (EBADF); if (fp->f_type != DTYPE_VNODE) { fd_putfile(fd); return (ENODEV); /* only mmap vnodes! */ } vp = fp->f_data; /* convert to vnode */ if (vp->v_type != VREG && vp->v_type != VCHR && vp->v_type != VBLK) { fd_putfile(fd); return (ENODEV); /* only REG/CHR/BLK support mmap */ } if (vp->v_type != VCHR && pos < 0) { fd_putfile(fd); return (EINVAL); } if (vp->v_type != VCHR && (off_t)(pos + size) < pos) { fd_putfile(fd); return (EOVERFLOW); /* no offset wrapping */ } /* special case: catch SunOS style /dev/zero */ if (vp->v_type == VCHR && (vp->v_rdev == zerodev || COMPAT_ZERODEV(vp->v_rdev))) { flags |= MAP_ANON; fd_putfile(fd); fp = NULL; 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)) == 0) { #if defined(DEBUG) printf("WARNING: defaulted mmap() share type to " "%s (pid %d command %s)\n", vp->v_type == VCHR ? "MAP_SHARED" : "MAP_PRIVATE", p->p_pid, p->p_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 = VM_PROT_EXECUTE; /* check read access */ if (fp->f_flag & FREAD) maxprot |= VM_PROT_READ; else if (prot & PROT_READ) { fd_putfile(fd); return (EACCES); } /* 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) { vn_lock(vp, LK_SHARED | LK_RETRY); error = VOP_GETATTR(vp, &va, l->l_cred); VOP_UNLOCK(vp); if (error) { fd_putfile(fd); return (error); } if ((va.va_flags & (SF_SNAPSHOT|IMMUTABLE|APPEND)) == 0) maxprot |= VM_PROT_WRITE; else if (prot & PROT_WRITE) { fd_putfile(fd); return (EPERM); } } else if (prot & PROT_WRITE) { fd_putfile(fd); return (EACCES); } } else { /* MAP_PRIVATE mappings can always write to */ maxprot |= VM_PROT_WRITE; } handle = vp; } else { /* MAP_ANON case */ /* * XXX What do we do about (MAP_SHARED|MAP_PRIVATE) == 0? */ if (fd != -1) return (EINVAL); is_anon: /* label for SunOS style /dev/zero */ handle = NULL; maxprot = VM_PROT_ALL; pos = 0; } #if NVERIEXEC > 0 if (handle != NULL) { /* * Check if the file can be executed indirectly. * * XXX: This gives false warnings about "Incorrect access type" * XXX: if the mapping is not executable. Harmless, but will be * XXX: fixed as part of other changes. */ if (veriexec_verify(l, handle, "(mmap)", VERIEXEC_INDIRECT, NULL)) { /* * Don't allow executable mappings if we can't * indirectly execute the file. */ if (prot & VM_PROT_EXECUTE) { if (fp != NULL) fd_putfile(fd); return (EPERM); } /* * Strip the executable bit from 'maxprot' to make sure * it can't be made executable later. */ maxprot &= ~VM_PROT_EXECUTE; } } #endif /* NVERIEXEC > 0 */ #ifdef PAX_MPROTECT pax_mprotect(l, &prot, &maxprot); #endif /* PAX_MPROTECT */ #ifdef PAX_ASLR pax_aslr(l, &addr, orig_addr, flags); #endif /* PAX_ASLR */ /* * now let kernel internal function uvm_mmap do the work. */ error = uvm_mmap(&p->p_vmspace->vm_map, &addr, size, prot, maxprot, flags, handle, pos, p->p_rlimit[RLIMIT_MEMLOCK].rlim_cur); if (error == 0) /* remember to add offset */ *retval = (register_t)(addr + pageoff); if (fp != NULL) fd_putfile(fd); return (error); } /* * sys___msync13: the msync system call (a front-end for flush) */ int sys___msync13(struct lwp *l, const struct sys___msync13_args *uap, register_t *retval) { /* { syscallarg(void *) addr; syscallarg(size_t) len; syscallarg(int) flags; } */ struct proc *p = l->l_proc; vaddr_t addr; vsize_t size, pageoff; struct vm_map *map; int error, rv, 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. */ pageoff = (addr & PAGE_MASK); addr -= pageoff; size += pageoff; size = (vsize_t)round_page(size); error = range_test(addr, size, false); if (error) return error; /* * 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) { struct vm_map_entry *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 = PGO_CLEANIT; if (flags & MS_INVALIDATE) uvmflags |= PGO_FREE; if (flags & MS_SYNC) uvmflags |= PGO_SYNCIO; error = uvm_map_clean(map, addr, addr+size, uvmflags); return error; } /* * sys_munmap: unmap a users memory */ int sys_munmap(struct lwp *l, const struct sys_munmap_args *uap, register_t *retval) { /* { syscallarg(void *) addr; syscallarg(size_t) len; } */ struct proc *p = l->l_proc; vaddr_t addr; vsize_t size, pageoff; struct vm_map *map; struct vm_map_entry *dead_entries; int error; /* * get syscall args. */ addr = (vaddr_t)SCARG(uap, addr); size = (vsize_t)SCARG(uap, len); /* * 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); if (size == 0) return (0); error = range_test(addr, size, false); if (error) return error; map = &p->p_vmspace->vm_map; /* * interesting system call semantic: make sure entire range is * allocated before allowing an unmap. */ vm_map_lock(map); #if 0 if (!uvm_map_checkprot(map, addr, addr + size, VM_PROT_NONE)) { vm_map_unlock(map); return (EINVAL); } #endif uvm_unmap_remove(map, addr, addr + size, &dead_entries, 0); vm_map_unlock(map); if (dead_entries != NULL) uvm_unmap_detach(dead_entries, 0); return (0); } /* * sys_mprotect: the mprotect system call */ int sys_mprotect(struct lwp *l, const struct sys_mprotect_args *uap, register_t *retval) { /* { syscallarg(void *) addr; syscallarg(size_t) len; syscallarg(int) prot; } */ struct proc *p = l->l_proc; 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) & VM_PROT_ALL; /* * align the address to a page boundary and adjust the size accordingly. */ pageoff = (addr & PAGE_MASK); addr -= pageoff; size += pageoff; size = round_page(size); error = range_test(addr, size, false); if (error) return error; error = uvm_map_protect(&p->p_vmspace->vm_map, addr, addr + size, prot, false); return error; } /* * sys_minherit: the minherit system call */ int sys_minherit(struct lwp *l, const struct sys_minherit_args *uap, register_t *retval) { /* { syscallarg(void *) addr; syscallarg(int) len; syscallarg(int) inherit; } */ struct proc *p = l->l_proc; vaddr_t addr; vsize_t size, pageoff; vm_inherit_t inherit; int error; 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. */ pageoff = (addr & PAGE_MASK); addr -= pageoff; size += pageoff; size = (vsize_t)round_page(size); error = range_test(addr, size, false); if (error) return error; error = uvm_map_inherit(&p->p_vmspace->vm_map, addr, addr + size, inherit); return error; } /* * sys_madvise: give advice about memory usage. */ /* ARGSUSED */ int sys_madvise(struct lwp *l, const struct sys_madvise_args *uap, register_t *retval) { /* { syscallarg(void *) addr; syscallarg(size_t) len; syscallarg(int) behav; } */ struct proc *p = l->l_proc; 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 */ pageoff = (addr & PAGE_MASK); addr -= pageoff; size += pageoff; size = (vsize_t)round_page(size); error = range_test(addr, size, false); if (error) return error; 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. */ error = uvm_map_willneed(&p->p_vmspace->vm_map, addr, addr + size); break; 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 lwp *l, const struct sys_mlock_args *uap, register_t *retval) { /* { syscallarg(const void *) addr; syscallarg(size_t) len; } */ struct proc *p = l->l_proc; 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 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); error = range_test(addr, size, false); if (error) return error; if (atop(size) + uvmexp.wired > uvmexp.wiredmax) return (EAGAIN); if (size + ptoa(pmap_wired_count(vm_map_pmap(&p->p_vmspace->vm_map))) > p->p_rlimit[RLIMIT_MEMLOCK].rlim_cur) return (EAGAIN); error = uvm_map_pageable(&p->p_vmspace->vm_map, addr, addr+size, false, 0); if (error == EFAULT) error = ENOMEM; return error; } /* * sys_munlock: unlock wired pages */ int sys_munlock(struct lwp *l, const struct sys_munlock_args *uap, register_t *retval) { /* { syscallarg(const void *) addr; syscallarg(size_t) len; } */ struct proc *p = l->l_proc; 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 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); error = range_test(addr, size, false); if (error) return error; error = uvm_map_pageable(&p->p_vmspace->vm_map, addr, addr+size, true, 0); if (error == EFAULT) error = ENOMEM; return error; } /* * sys_mlockall: lock all pages mapped into an address space. */ int sys_mlockall(struct lwp *l, const struct sys_mlockall_args *uap, register_t *retval) { /* { syscallarg(int) flags; } */ struct proc *p = l->l_proc; int error, flags; flags = SCARG(uap, flags); if (flags == 0 || (flags & ~(MCL_CURRENT|MCL_FUTURE)) != 0) return (EINVAL); error = uvm_map_pageable_all(&p->p_vmspace->vm_map, flags, p->p_rlimit[RLIMIT_MEMLOCK].rlim_cur); return (error); } /* * sys_munlockall: unlock all pages mapped into an address space. */ int sys_munlockall(struct lwp *l, const void *v, register_t *retval) { struct proc *p = l->l_proc; (void) uvm_map_pageable_all(&p->p_vmspace->vm_map, 0, 0); return (0); } /* * uvm_mmap: internal version of mmap * * - used by sys_mmap and various framebuffers * - handle is a vnode pointer or NULL for MAP_ANON * - caller must page-align the file offset */ int uvm_mmap(struct vm_map *map, vaddr_t *addr, vsize_t size, vm_prot_t prot, vm_prot_t maxprot, int flags, void *handle, voff_t foff, vsize_t locklimit) { struct uvm_object *uobj; struct vnode *vp; vaddr_t align = 0; int error; int advice = UVM_ADV_NORMAL; uvm_flag_t uvmflag = 0; bool needwritemap; /* * 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); } else { if (*addr & PAGE_MASK) return(EINVAL); uvmflag |= UVM_FLAG_FIXED; (void) uvm_unmap(map, *addr, *addr + size); } /* * Try to see if any requested alignment can even be attemped. * Make sure we can express the alignment (asking for a >= 4GB * alignment on an ILP32 architecure make no sense) and the * alignment is at least for a page sized quanitiy. If the * request was for a fixed mapping, make sure supplied address * adheres to the request alignment. */ align = (flags & MAP_ALIGNMENT_MASK) >> MAP_ALIGNMENT_SHIFT; if (align) { if (align >= sizeof(vaddr_t) * NBBY) return(EINVAL); align = 1L << align; if (align < PAGE_SIZE) return(EINVAL); if (align >= vm_map_max(map)) return(ENOMEM); if (flags & MAP_FIXED) { if ((*addr & (align-1)) != 0) return(EINVAL); align = 0; } } /* * check resource limits */ if (!VM_MAP_IS_KERNEL(map) && (((rlim_t)curproc->p_vmspace->vm_map.size + (rlim_t)size) > curproc->p_rlimit[RLIMIT_AS].rlim_cur)) return ENOMEM; /* * handle anon vs. non-anon mappings. for non-anon mappings attach * to underlying vm object. */ if (flags & MAP_ANON) { KASSERT(handle == NULL); 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 { KASSERT(handle != NULL); vp = (struct vnode *)handle; /* * Don't allow mmap for EXEC if the file system * is mounted NOEXEC. */ if ((prot & PROT_EXEC) != 0 && (vp->v_mount->mnt_flag & MNT_NOEXEC) != 0) return (EACCES); if (vp->v_type != VCHR) { error = VOP_MMAP(vp, prot, curlwp->l_cred); if (error) { return error; } vref(vp); uobj = &vp->v_uobj; /* * If the vnode is being mapped with PROT_EXEC, * then mark it as text. */ if (prot & PROT_EXEC) { vn_markexec(vp); } } else { int i = maxprot; /* * XXX Some devices don't like to be mapped with * XXX PROT_EXEC or PROT_WRITE, but we don't really * XXX have a better way of handling this, right now */ do { uobj = udv_attach((void *) &vp->v_rdev, (flags & MAP_SHARED) ? i : (i & ~VM_PROT_WRITE), foff, size); i--; } while ((uobj == NULL) && (i > 0)); if (uobj == NULL) return EINVAL; advice = UVM_ADV_RANDOM; } if ((flags & MAP_SHARED) == 0) { uvmflag |= UVM_FLAG_COPYONW; } /* * Set vnode flags to indicate the new kinds of mapping. * We take the vnode lock in exclusive mode here to serialize * with direct I/O. * * Safe to check for these flag values without a lock, as * long as a reference to the vnode is held. */ needwritemap = (vp->v_iflag & VI_WRMAP) == 0 && (flags & MAP_SHARED) != 0 && (maxprot & VM_PROT_WRITE) != 0; if ((vp->v_vflag & VV_MAPPED) == 0 || needwritemap) { vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); vp->v_vflag |= VV_MAPPED; if (needwritemap) { mutex_enter(vp->v_interlock); vp->v_iflag |= VI_WRMAP; mutex_exit(vp->v_interlock); } VOP_UNLOCK(vp); } } uvmflag = UVM_MAPFLAG(prot, maxprot, (flags & MAP_SHARED) ? UVM_INH_SHARE : UVM_INH_COPY, advice, uvmflag); error = uvm_map(map, addr, size, uobj, foff, align, uvmflag); if (error) { if (uobj) uobj->pgops->pgo_detach(uobj); return error; } /* * POSIX 1003.1b -- if our address space was configured * to lock all future mappings, wire the one we just made. * * Also handle the MAP_WIRED flag here. */ if (prot == VM_PROT_NONE) { /* * No more work to do in this case. */ return (0); } if ((flags & MAP_WIRED) != 0 || (map->flags & VM_MAP_WIREFUTURE) != 0) { vm_map_lock(map); if (atop(size) + uvmexp.wired > uvmexp.wiredmax || (locklimit != 0 && size + ptoa(pmap_wired_count(vm_map_pmap(map))) > locklimit)) { vm_map_unlock(map); uvm_unmap(map, *addr, *addr + size); return ENOMEM; } /* * uvm_map_pageable() always returns the map unlocked. */ error = uvm_map_pageable(map, *addr, *addr + size, false, UVM_LK_ENTER); if (error) { uvm_unmap(map, *addr, *addr + size); return error; } return (0); } return 0; } vaddr_t uvm_default_mapaddr(struct proc *p, vaddr_t base, vsize_t sz) { return VM_DEFAULT_ADDRESS(base, sz); }