diff options
Diffstat (limited to 'sys/vm/vm_mmap.c')
-rw-r--r-- | sys/vm/vm_mmap.c | 105 |
1 files changed, 47 insertions, 58 deletions
diff --git a/sys/vm/vm_mmap.c b/sys/vm/vm_mmap.c index 6cc0acc..c79a0f4 100644 --- a/sys/vm/vm_mmap.c +++ b/sys/vm/vm_mmap.c @@ -117,9 +117,9 @@ vmmapentry_rsrc_init(dummy) } static int vm_mmap_vnode(struct thread *, vm_size_t, vm_prot_t, vm_prot_t *, - int *, struct vnode *, vm_ooffset_t, vm_object_t *); + int *, struct vnode *, vm_ooffset_t *, vm_object_t *); static int vm_mmap_cdev(struct thread *, vm_size_t, vm_prot_t, vm_prot_t *, - int *, struct cdev *, vm_ooffset_t, vm_object_t *); + int *, struct cdev *, vm_ooffset_t *, vm_object_t *); static int vm_mmap_shm(struct thread *, vm_size_t, vm_prot_t, vm_prot_t *, int *, struct shmfd *, vm_ooffset_t, vm_object_t *); @@ -1142,15 +1142,14 @@ munlock(td, uap) int vm_mmap_vnode(struct thread *td, vm_size_t objsize, vm_prot_t prot, vm_prot_t *maxprotp, int *flagsp, - struct vnode *vp, vm_ooffset_t foff, vm_object_t *objp) + struct vnode *vp, vm_ooffset_t *foffp, vm_object_t *objp) { struct vattr va; - void *handle; vm_object_t obj; + vm_offset_t foff; struct mount *mp; - struct cdevsw *dsw; struct ucred *cred; - int error, flags, type; + int error, flags; int vfslocked; mp = vp->v_mount; @@ -1160,6 +1159,7 @@ vm_mmap_vnode(struct thread *td, vm_size_t objsize, VFS_UNLOCK_GIANT(vfslocked); return (error); } + foff = *foffp; flags = *flagsp; obj = vp->v_object; if (vp->v_type == VREG) { @@ -1175,41 +1175,12 @@ vm_mmap_vnode(struct thread *td, vm_size_t objsize, vp = (struct vnode*)obj->handle; vget(vp, LK_SHARED, td); } - type = OBJT_VNODE; - handle = vp; } else if (vp->v_type == VCHR) { - type = OBJT_DEVICE; - handle = vp->v_rdev; - - dsw = dev_refthread(handle); - if (dsw == NULL) { - error = ENXIO; - goto done; - } - if (dsw->d_flags & D_MMAP_ANON) { - dev_relthread(handle); - *maxprotp = VM_PROT_ALL; - *flagsp |= MAP_ANON; - error = 0; - goto done; - } - dev_relthread(handle); - /* - * cdevs does not provide private mappings of any kind. - */ - if ((*maxprotp & VM_PROT_WRITE) == 0 && - (prot & PROT_WRITE) != 0) { - error = EACCES; - goto done; - } - if (flags & (MAP_PRIVATE|MAP_COPY)) { - error = EINVAL; - goto done; - } - /* - * Force device mappings to be shared. - */ - flags |= MAP_SHARED; + error = vm_mmap_cdev(td, objsize, prot, maxprotp, flagsp, + vp->v_rdev, foffp, objp); + if (error == 0) + goto mark_atime; + goto done; } else { error = EINVAL; goto done; @@ -1235,18 +1206,18 @@ vm_mmap_vnode(struct thread *td, vm_size_t objsize, * we do not need to sync it. * Adjust object size to be the size of actual file. */ - if (vp->v_type == VREG) { - objsize = round_page(va.va_size); - if (va.va_nlink == 0) - flags |= MAP_NOSYNC; - } - obj = vm_pager_allocate(type, handle, objsize, prot, foff); + objsize = round_page(va.va_size); + if (va.va_nlink == 0) + flags |= MAP_NOSYNC; + obj = vm_pager_allocate(OBJT_VNODE, vp, objsize, prot, foff); if (obj == NULL) { - error = (type == OBJT_DEVICE ? EINVAL : ENOMEM); + error = ENOMEM; goto done; } *objp = obj; *flagsp = flags; + +mark_atime: vfs_mark_atime(vp, cred); done: @@ -1266,11 +1237,11 @@ done: int vm_mmap_cdev(struct thread *td, vm_size_t objsize, vm_prot_t prot, vm_prot_t *maxprotp, int *flagsp, - struct cdev *cdev, vm_ooffset_t foff, vm_object_t *objp) + struct cdev *cdev, vm_ooffset_t *foff, vm_object_t *objp) { vm_object_t obj; struct cdevsw *dsw; - int flags; + int error, flags; flags = *flagsp; @@ -1283,25 +1254,43 @@ vm_mmap_cdev(struct thread *td, vm_size_t objsize, *flagsp |= MAP_ANON; return (0); } - dev_relthread(cdev); /* - * cdevs does not provide private mappings of any kind. + * cdevs do not provide private mappings of any kind. */ if ((*maxprotp & VM_PROT_WRITE) == 0 && - (prot & PROT_WRITE) != 0) + (prot & PROT_WRITE) != 0) { + dev_relthread(cdev); return (EACCES); - if (flags & (MAP_PRIVATE|MAP_COPY)) + } + if (flags & (MAP_PRIVATE|MAP_COPY)) { + dev_relthread(cdev); return (EINVAL); + } /* * Force device mappings to be shared. */ flags |= MAP_SHARED; #ifdef MAC_XXX - error = mac_check_cdev_mmap(td->td_ucred, cdev, prot); - if (error != 0) + error = mac_cdev_check_mmap(td->td_ucred, cdev, prot); + if (error != 0) { + dev_relthread(cdev); return (error); + } #endif - obj = vm_pager_allocate(OBJT_DEVICE, cdev, objsize, prot, foff); + /* + * First, try d_mmap_single(). If that is not implemented + * (returns ENODEV), fall back to using the device pager. + * Note that d_mmap_single() must return a reference to the + * object (it needs to bump the reference count of the object + * it returns somehow). + * + * XXX assumes VM_PROT_* == PROT_* + */ + error = dsw->d_mmap_single(cdev, foff, objsize, objp, (int)prot); + dev_relthread(cdev); + if (error != ENODEV) + return (error); + obj = vm_pager_allocate(OBJT_DEVICE, cdev, objsize, prot, *foff); if (obj == NULL) return (EINVAL); *objp = obj; @@ -1396,11 +1385,11 @@ vm_mmap(vm_map_t map, vm_offset_t *addr, vm_size_t size, vm_prot_t prot, switch (handle_type) { case OBJT_DEVICE: error = vm_mmap_cdev(td, size, prot, &maxprot, &flags, - handle, foff, &object); + handle, &foff, &object); break; case OBJT_VNODE: error = vm_mmap_vnode(td, size, prot, &maxprot, &flags, - handle, foff, &object); + handle, &foff, &object); break; case OBJT_SWAP: error = vm_mmap_shm(td, size, prot, &maxprot, &flags, |