/* $NetBSD: tmpfs_vnops.c,v 1.39 2007/07/23 15:41:01 jmmv Exp $ */ /*- * Copyright (c) 2005, 2006 The NetBSD Foundation, Inc. * All rights reserved. * * This code is derived from software contributed to The NetBSD Foundation * by Julio M. Merino Vidal, developed as part of Google's Summer of Code * 2005 program. * * 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. * * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. 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 FOUNDATION 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. */ /* * tmpfs vnode interface. */ #include __FBSDID("$FreeBSD$"); #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include SYSCTL_DECL(_vfs_tmpfs); static volatile int tmpfs_rename_restarts; SYSCTL_INT(_vfs_tmpfs, OID_AUTO, rename_restarts, CTLFLAG_RD, __DEVOLATILE(int *, &tmpfs_rename_restarts), 0, "Times rename had to restart due to lock contention"); /* --------------------------------------------------------------------- */ static int tmpfs_lookup(struct vop_cachedlookup_args *v) { struct vnode *dvp = v->a_dvp; struct vnode **vpp = v->a_vpp; struct componentname *cnp = v->a_cnp; int error; struct tmpfs_dirent *de; struct tmpfs_node *dnode; dnode = VP_TO_TMPFS_DIR(dvp); *vpp = NULLVP; /* Check accessibility of requested node as a first step. */ error = VOP_ACCESS(dvp, VEXEC, cnp->cn_cred, cnp->cn_thread); if (error != 0) goto out; /* We cannot be requesting the parent directory of the root node. */ MPASS(IMPLIES(dnode->tn_type == VDIR && dnode->tn_dir.tn_parent == dnode, !(cnp->cn_flags & ISDOTDOT))); TMPFS_ASSERT_LOCKED(dnode); if (dnode->tn_dir.tn_parent == NULL) { error = ENOENT; goto out; } if (cnp->cn_flags & ISDOTDOT) { int ltype = 0; ltype = VOP_ISLOCKED(dvp); vhold(dvp); VOP_UNLOCK(dvp, 0); /* Allocate a new vnode on the matching entry. */ error = tmpfs_alloc_vp(dvp->v_mount, dnode->tn_dir.tn_parent, cnp->cn_lkflags, vpp); vn_lock(dvp, ltype | LK_RETRY); vdrop(dvp); } else if (cnp->cn_namelen == 1 && cnp->cn_nameptr[0] == '.') { VREF(dvp); *vpp = dvp; error = 0; } else { de = tmpfs_dir_lookup(dnode, NULL, cnp); if (de != NULL && de->td_node == NULL) cnp->cn_flags |= ISWHITEOUT; if (de == NULL || de->td_node == NULL) { /* The entry was not found in the directory. * This is OK if we are creating or renaming an * entry and are working on the last component of * the path name. */ if ((cnp->cn_flags & ISLASTCN) && (cnp->cn_nameiop == CREATE || \ cnp->cn_nameiop == RENAME || (cnp->cn_nameiop == DELETE && cnp->cn_flags & DOWHITEOUT && cnp->cn_flags & ISWHITEOUT))) { error = VOP_ACCESS(dvp, VWRITE, cnp->cn_cred, cnp->cn_thread); if (error != 0) goto out; /* Keep the component name in the buffer for * future uses. */ cnp->cn_flags |= SAVENAME; error = EJUSTRETURN; } else error = ENOENT; } else { struct tmpfs_node *tnode; /* The entry was found, so get its associated * tmpfs_node. */ tnode = de->td_node; /* If we are not at the last path component and * found a non-directory or non-link entry (which * may itself be pointing to a directory), raise * an error. */ if ((tnode->tn_type != VDIR && tnode->tn_type != VLNK) && !(cnp->cn_flags & ISLASTCN)) { error = ENOTDIR; goto out; } /* If we are deleting or renaming the entry, keep * track of its tmpfs_dirent so that it can be * easily deleted later. */ if ((cnp->cn_flags & ISLASTCN) && (cnp->cn_nameiop == DELETE || cnp->cn_nameiop == RENAME)) { error = VOP_ACCESS(dvp, VWRITE, cnp->cn_cred, cnp->cn_thread); if (error != 0) goto out; /* Allocate a new vnode on the matching entry. */ error = tmpfs_alloc_vp(dvp->v_mount, tnode, cnp->cn_lkflags, vpp); if (error != 0) goto out; if ((dnode->tn_mode & S_ISTXT) && VOP_ACCESS(dvp, VADMIN, cnp->cn_cred, cnp->cn_thread) && VOP_ACCESS(*vpp, VADMIN, cnp->cn_cred, cnp->cn_thread)) { error = EPERM; vput(*vpp); *vpp = NULL; goto out; } cnp->cn_flags |= SAVENAME; } else { error = tmpfs_alloc_vp(dvp->v_mount, tnode, cnp->cn_lkflags, vpp); } } } /* Store the result of this lookup in the cache. Avoid this if the * request was for creation, as it does not improve timings on * emprical tests. */ if ((cnp->cn_flags & MAKEENTRY) && cnp->cn_nameiop != CREATE) cache_enter(dvp, *vpp, cnp); out: /* If there were no errors, *vpp cannot be null and it must be * locked. */ MPASS(IFF(error == 0, *vpp != NULLVP && VOP_ISLOCKED(*vpp))); return error; } /* --------------------------------------------------------------------- */ static int tmpfs_create(struct vop_create_args *v) { struct vnode *dvp = v->a_dvp; struct vnode **vpp = v->a_vpp; struct componentname *cnp = v->a_cnp; struct vattr *vap = v->a_vap; MPASS(vap->va_type == VREG || vap->va_type == VSOCK); return tmpfs_alloc_file(dvp, vpp, vap, cnp, NULL); } /* --------------------------------------------------------------------- */ static int tmpfs_mknod(struct vop_mknod_args *v) { struct vnode *dvp = v->a_dvp; struct vnode **vpp = v->a_vpp; struct componentname *cnp = v->a_cnp; struct vattr *vap = v->a_vap; if (vap->va_type != VBLK && vap->va_type != VCHR && vap->va_type != VFIFO) return EINVAL; return tmpfs_alloc_file(dvp, vpp, vap, cnp, NULL); } /* --------------------------------------------------------------------- */ static int tmpfs_open(struct vop_open_args *v) { struct vnode *vp = v->a_vp; int mode = v->a_mode; int error; struct tmpfs_node *node; MPASS(VOP_ISLOCKED(vp)); node = VP_TO_TMPFS_NODE(vp); /* The file is still active but all its names have been removed * (e.g. by a "rmdir $(pwd)"). It cannot be opened any more as * it is about to die. */ if (node->tn_links < 1) return (ENOENT); /* If the file is marked append-only, deny write requests. */ if (node->tn_flags & APPEND && (mode & (FWRITE | O_APPEND)) == FWRITE) error = EPERM; else { error = 0; vnode_create_vobject(vp, node->tn_size, v->a_td); } MPASS(VOP_ISLOCKED(vp)); return error; } /* --------------------------------------------------------------------- */ static int tmpfs_close(struct vop_close_args *v) { struct vnode *vp = v->a_vp; MPASS(VOP_ISLOCKED(vp)); /* Update node times. */ tmpfs_update(vp); return (0); } /* --------------------------------------------------------------------- */ int tmpfs_access(struct vop_access_args *v) { struct vnode *vp = v->a_vp; accmode_t accmode = v->a_accmode; struct ucred *cred = v->a_cred; int error; struct tmpfs_node *node; MPASS(VOP_ISLOCKED(vp)); node = VP_TO_TMPFS_NODE(vp); switch (vp->v_type) { case VDIR: /* FALLTHROUGH */ case VLNK: /* FALLTHROUGH */ case VREG: if (accmode & VWRITE && vp->v_mount->mnt_flag & MNT_RDONLY) { error = EROFS; goto out; } break; case VBLK: /* FALLTHROUGH */ case VCHR: /* FALLTHROUGH */ case VSOCK: /* FALLTHROUGH */ case VFIFO: break; default: error = EINVAL; goto out; } if (accmode & VWRITE && node->tn_flags & IMMUTABLE) { error = EPERM; goto out; } error = vaccess(vp->v_type, node->tn_mode, node->tn_uid, node->tn_gid, accmode, cred, NULL); out: MPASS(VOP_ISLOCKED(vp)); return error; } /* --------------------------------------------------------------------- */ int tmpfs_getattr(struct vop_getattr_args *v) { struct vnode *vp = v->a_vp; struct vattr *vap = v->a_vap; struct tmpfs_node *node; node = VP_TO_TMPFS_NODE(vp); tmpfs_update(vp); vap->va_type = vp->v_type; vap->va_mode = node->tn_mode; vap->va_nlink = node->tn_links; vap->va_uid = node->tn_uid; vap->va_gid = node->tn_gid; vap->va_fsid = vp->v_mount->mnt_stat.f_fsid.val[0]; vap->va_fileid = node->tn_id; vap->va_size = node->tn_size; vap->va_blocksize = PAGE_SIZE; vap->va_atime = node->tn_atime; vap->va_mtime = node->tn_mtime; vap->va_ctime = node->tn_ctime; vap->va_birthtime = node->tn_birthtime; vap->va_gen = node->tn_gen; vap->va_flags = node->tn_flags; vap->va_rdev = (vp->v_type == VBLK || vp->v_type == VCHR) ? node->tn_rdev : NODEV; vap->va_bytes = round_page(node->tn_size); vap->va_filerev = 0; return 0; } /* --------------------------------------------------------------------- */ /* XXX Should this operation be atomic? I think it should, but code in * XXX other places (e.g., ufs) doesn't seem to be... */ int tmpfs_setattr(struct vop_setattr_args *v) { struct vnode *vp = v->a_vp; struct vattr *vap = v->a_vap; struct ucred *cred = v->a_cred; struct thread *td = curthread; int error; MPASS(VOP_ISLOCKED(vp)); error = 0; /* Abort if any unsettable attribute is given. */ if (vap->va_type != VNON || vap->va_nlink != VNOVAL || vap->va_fsid != VNOVAL || vap->va_fileid != VNOVAL || vap->va_blocksize != VNOVAL || vap->va_gen != VNOVAL || vap->va_rdev != VNOVAL || vap->va_bytes != VNOVAL) error = EINVAL; if (error == 0 && (vap->va_flags != VNOVAL)) error = tmpfs_chflags(vp, vap->va_flags, cred, td); if (error == 0 && (vap->va_size != VNOVAL)) error = tmpfs_chsize(vp, vap->va_size, cred, td); if (error == 0 && (vap->va_uid != VNOVAL || vap->va_gid != VNOVAL)) error = tmpfs_chown(vp, vap->va_uid, vap->va_gid, cred, td); if (error == 0 && (vap->va_mode != (mode_t)VNOVAL)) error = tmpfs_chmod(vp, vap->va_mode, cred, td); if (error == 0 && ((vap->va_atime.tv_sec != VNOVAL && vap->va_atime.tv_nsec != VNOVAL) || (vap->va_mtime.tv_sec != VNOVAL && vap->va_mtime.tv_nsec != VNOVAL) || (vap->va_birthtime.tv_sec != VNOVAL && vap->va_birthtime.tv_nsec != VNOVAL))) error = tmpfs_chtimes(vp, &vap->va_atime, &vap->va_mtime, &vap->va_birthtime, vap->va_vaflags, cred, td); /* Update the node times. We give preference to the error codes * generated by this function rather than the ones that may arise * from tmpfs_update. */ tmpfs_update(vp); MPASS(VOP_ISLOCKED(vp)); return error; } /* --------------------------------------------------------------------- */ static int tmpfs_nocacheread(vm_object_t tobj, vm_pindex_t idx, vm_offset_t offset, size_t tlen, struct uio *uio) { vm_page_t m; int error, rv; VM_OBJECT_WLOCK(tobj); m = vm_page_grab(tobj, idx, VM_ALLOC_WIRED | VM_ALLOC_NORMAL | VM_ALLOC_RETRY); if (m->valid != VM_PAGE_BITS_ALL) { if (vm_pager_has_page(tobj, idx, NULL, NULL)) { rv = vm_pager_get_pages(tobj, &m, 1, 0); if (rv != VM_PAGER_OK) { vm_page_lock(m); vm_page_free(m); vm_page_unlock(m); VM_OBJECT_WUNLOCK(tobj); return (EIO); } } else vm_page_zero_invalid(m, TRUE); } VM_OBJECT_WUNLOCK(tobj); error = uiomove_fromphys(&m, offset, tlen, uio); VM_OBJECT_WLOCK(tobj); vm_page_lock(m); vm_page_unwire(m, TRUE); vm_page_unlock(m); vm_page_wakeup(m); VM_OBJECT_WUNLOCK(tobj); return (error); } static __inline int tmpfs_nocacheread_buf(vm_object_t tobj, vm_pindex_t idx, vm_offset_t offset, size_t tlen, void *buf) { struct uio uio; struct iovec iov; uio.uio_iovcnt = 1; uio.uio_iov = &iov; iov.iov_base = buf; iov.iov_len = tlen; uio.uio_offset = 0; uio.uio_resid = tlen; uio.uio_rw = UIO_READ; uio.uio_segflg = UIO_SYSSPACE; uio.uio_td = curthread; return (tmpfs_nocacheread(tobj, idx, offset, tlen, &uio)); } static int tmpfs_mappedread(vm_object_t vobj, vm_object_t tobj, size_t len, struct uio *uio) { struct sf_buf *sf; vm_pindex_t idx; vm_page_t m; vm_offset_t offset; off_t addr; size_t tlen; char *ma; int error; addr = uio->uio_offset; idx = OFF_TO_IDX(addr); offset = addr & PAGE_MASK; tlen = MIN(PAGE_SIZE - offset, len); VM_OBJECT_WLOCK(vobj); lookupvpg: if (((m = vm_page_lookup(vobj, idx)) != NULL) && vm_page_is_valid(m, offset, tlen)) { if ((m->oflags & VPO_BUSY) != 0) { /* * Reference the page before unlocking and sleeping so * that the page daemon is less likely to reclaim it. */ vm_page_reference(m); vm_page_sleep(m, "tmfsmr"); goto lookupvpg; } vm_page_busy(m); VM_OBJECT_WUNLOCK(vobj); error = uiomove_fromphys(&m, offset, tlen, uio); VM_OBJECT_WLOCK(vobj); vm_page_wakeup(m); VM_OBJECT_WUNLOCK(vobj); return (error); } else if (m != NULL && uio->uio_segflg == UIO_NOCOPY) { KASSERT(offset == 0, ("unexpected offset in tmpfs_mappedread for sendfile")); if ((m->oflags & VPO_BUSY) != 0) { /* * Reference the page before unlocking and sleeping so * that the page daemon is less likely to reclaim it. */ vm_page_reference(m); vm_page_sleep(m, "tmfsmr"); goto lookupvpg; } vm_page_busy(m); VM_OBJECT_WUNLOCK(vobj); sched_pin(); sf = sf_buf_alloc(m, SFB_CPUPRIVATE); ma = (char *)sf_buf_kva(sf); error = tmpfs_nocacheread_buf(tobj, idx, 0, tlen, ma); if (error == 0) { if (tlen != PAGE_SIZE) bzero(ma + tlen, PAGE_SIZE - tlen); uio->uio_offset += tlen; uio->uio_resid -= tlen; } sf_buf_free(sf); sched_unpin(); VM_OBJECT_WLOCK(vobj); if (error == 0) m->valid = VM_PAGE_BITS_ALL; vm_page_wakeup(m); VM_OBJECT_WUNLOCK(vobj); return (error); } VM_OBJECT_WUNLOCK(vobj); error = tmpfs_nocacheread(tobj, idx, offset, tlen, uio); return (error); } static int tmpfs_read(struct vop_read_args *v) { struct vnode *vp = v->a_vp; struct uio *uio = v->a_uio; struct tmpfs_node *node; vm_object_t uobj; size_t len; int resid; int error = 0; node = VP_TO_TMPFS_NODE(vp); if (vp->v_type != VREG) { error = EISDIR; goto out; } if (uio->uio_offset < 0) { error = EINVAL; goto out; } node->tn_status |= TMPFS_NODE_ACCESSED; uobj = node->tn_reg.tn_aobj; while ((resid = uio->uio_resid) > 0) { error = 0; if (node->tn_size <= uio->uio_offset) break; len = MIN(node->tn_size - uio->uio_offset, resid); if (len == 0) break; error = tmpfs_mappedread(vp->v_object, uobj, len, uio); if ((error != 0) || (resid == uio->uio_resid)) break; } out: return error; } /* --------------------------------------------------------------------- */ static int tmpfs_mappedwrite(vm_object_t vobj, vm_object_t tobj, size_t len, struct uio *uio) { vm_pindex_t idx; vm_page_t vpg, tpg; vm_offset_t offset; off_t addr; size_t tlen; int error, rv; error = 0; addr = uio->uio_offset; idx = OFF_TO_IDX(addr); offset = addr & PAGE_MASK; tlen = MIN(PAGE_SIZE - offset, len); VM_OBJECT_WLOCK(vobj); lookupvpg: if (((vpg = vm_page_lookup(vobj, idx)) != NULL) && vm_page_is_valid(vpg, offset, tlen)) { if ((vpg->oflags & VPO_BUSY) != 0) { /* * Reference the page before unlocking and sleeping so * that the page daemon is less likely to reclaim it. */ vm_page_reference(vpg); vm_page_sleep(vpg, "tmfsmw"); goto lookupvpg; } vm_page_busy(vpg); vm_page_undirty(vpg); VM_OBJECT_WUNLOCK(vobj); error = uiomove_fromphys(&vpg, offset, tlen, uio); } else { if (vm_page_is_cached(vobj, idx)) vm_page_cache_free(vobj, idx, idx + 1); VM_OBJECT_WUNLOCK(vobj); vpg = NULL; } VM_OBJECT_WLOCK(tobj); tpg = vm_page_grab(tobj, idx, VM_ALLOC_WIRED | VM_ALLOC_NORMAL | VM_ALLOC_RETRY); if (tpg->valid != VM_PAGE_BITS_ALL) { if (vm_pager_has_page(tobj, idx, NULL, NULL)) { rv = vm_pager_get_pages(tobj, &tpg, 1, 0); if (rv != VM_PAGER_OK) { vm_page_lock(tpg); vm_page_free(tpg); vm_page_unlock(tpg); error = EIO; goto out; } } else vm_page_zero_invalid(tpg, TRUE); } VM_OBJECT_WUNLOCK(tobj); if (vpg == NULL) error = uiomove_fromphys(&tpg, offset, tlen, uio); else { KASSERT(vpg->valid == VM_PAGE_BITS_ALL, ("parts of vpg invalid")); pmap_copy_page(vpg, tpg); } VM_OBJECT_WLOCK(tobj); if (error == 0) { KASSERT(tpg->valid == VM_PAGE_BITS_ALL, ("parts of tpg invalid")); vm_page_dirty(tpg); } vm_page_lock(tpg); vm_page_unwire(tpg, TRUE); vm_page_unlock(tpg); vm_page_wakeup(tpg); out: VM_OBJECT_WUNLOCK(tobj); if (vpg != NULL) { VM_OBJECT_WLOCK(vobj); vm_page_wakeup(vpg); VM_OBJECT_WUNLOCK(vobj); } return (error); } static int tmpfs_write(struct vop_write_args *v) { struct vnode *vp = v->a_vp; struct uio *uio = v->a_uio; int ioflag = v->a_ioflag; boolean_t extended; int error = 0; off_t oldsize; struct tmpfs_node *node; vm_object_t uobj; size_t len; int resid; node = VP_TO_TMPFS_NODE(vp); oldsize = node->tn_size; if (uio->uio_offset < 0 || vp->v_type != VREG) { error = EINVAL; goto out; } if (uio->uio_resid == 0) { error = 0; goto out; } if (ioflag & IO_APPEND) uio->uio_offset = node->tn_size; if (uio->uio_offset + uio->uio_resid > VFS_TO_TMPFS(vp->v_mount)->tm_maxfilesize) return (EFBIG); if (vn_rlimit_fsize(vp, uio, uio->uio_td)) return (EFBIG); extended = uio->uio_offset + uio->uio_resid > node->tn_size; if (extended) { error = tmpfs_reg_resize(vp, uio->uio_offset + uio->uio_resid, FALSE); if (error != 0) goto out; } uobj = node->tn_reg.tn_aobj; while ((resid = uio->uio_resid) > 0) { if (node->tn_size <= uio->uio_offset) break; len = MIN(node->tn_size - uio->uio_offset, resid); if (len == 0) break; error = tmpfs_mappedwrite(vp->v_object, uobj, len, uio); if ((error != 0) || (resid == uio->uio_resid)) break; } node->tn_status |= TMPFS_NODE_ACCESSED | TMPFS_NODE_MODIFIED | (extended ? TMPFS_NODE_CHANGED : 0); if (node->tn_mode & (S_ISUID | S_ISGID)) { if (priv_check_cred(v->a_cred, PRIV_VFS_RETAINSUGID, 0)) node->tn_mode &= ~(S_ISUID | S_ISGID); } if (error != 0) (void)tmpfs_reg_resize(vp, oldsize, TRUE); out: MPASS(IMPLIES(error == 0, uio->uio_resid == 0)); MPASS(IMPLIES(error != 0, oldsize == node->tn_size)); return error; } /* --------------------------------------------------------------------- */ static int tmpfs_fsync(struct vop_fsync_args *v) { struct vnode *vp = v->a_vp; MPASS(VOP_ISLOCKED(vp)); tmpfs_update(vp); return 0; } /* --------------------------------------------------------------------- */ static int tmpfs_remove(struct vop_remove_args *v) { struct vnode *dvp = v->a_dvp; struct vnode *vp = v->a_vp; int error; struct tmpfs_dirent *de; struct tmpfs_mount *tmp; struct tmpfs_node *dnode; struct tmpfs_node *node; MPASS(VOP_ISLOCKED(dvp)); MPASS(VOP_ISLOCKED(vp)); if (vp->v_type == VDIR) { error = EISDIR; goto out; } dnode = VP_TO_TMPFS_DIR(dvp); node = VP_TO_TMPFS_NODE(vp); tmp = VFS_TO_TMPFS(vp->v_mount); de = tmpfs_dir_lookup(dnode, node, v->a_cnp); MPASS(de != NULL); /* Files marked as immutable or append-only cannot be deleted. */ if ((node->tn_flags & (IMMUTABLE | APPEND | NOUNLINK)) || (dnode->tn_flags & APPEND)) { error = EPERM; goto out; } /* Remove the entry from the directory; as it is a file, we do not * have to change the number of hard links of the directory. */ tmpfs_dir_detach(dvp, de); if (v->a_cnp->cn_flags & DOWHITEOUT) tmpfs_dir_whiteout_add(dvp, v->a_cnp); /* Free the directory entry we just deleted. Note that the node * referred by it will not be removed until the vnode is really * reclaimed. */ tmpfs_free_dirent(tmp, de); node->tn_status |= TMPFS_NODE_ACCESSED | TMPFS_NODE_CHANGED; error = 0; out: return error; } /* --------------------------------------------------------------------- */ static int tmpfs_link(struct vop_link_args *v) { struct vnode *dvp = v->a_tdvp; struct vnode *vp = v->a_vp; struct componentname *cnp = v->a_cnp; int error; struct tmpfs_dirent *de; struct tmpfs_node *node; MPASS(VOP_ISLOCKED(dvp)); MPASS(cnp->cn_flags & HASBUF); MPASS(dvp != vp); /* XXX When can this be false? */ node = VP_TO_TMPFS_NODE(vp); /* XXX: Why aren't the following two tests done by the caller? */ /* Hard links of directories are forbidden. */ if (vp->v_type == VDIR) { error = EPERM; goto out; } /* Cannot create cross-device links. */ if (dvp->v_mount != vp->v_mount) { error = EXDEV; goto out; } /* Ensure that we do not overflow the maximum number of links imposed * by the system. */ MPASS(node->tn_links <= LINK_MAX); if (node->tn_links == LINK_MAX) { error = EMLINK; goto out; } /* We cannot create links of files marked immutable or append-only. */ if (node->tn_flags & (IMMUTABLE | APPEND)) { error = EPERM; goto out; } /* Allocate a new directory entry to represent the node. */ error = tmpfs_alloc_dirent(VFS_TO_TMPFS(vp->v_mount), node, cnp->cn_nameptr, cnp->cn_namelen, &de); if (error != 0) goto out; /* Insert the new directory entry into the appropriate directory. */ if (cnp->cn_flags & ISWHITEOUT) tmpfs_dir_whiteout_remove(dvp, cnp); tmpfs_dir_attach(dvp, de); /* vp link count has changed, so update node times. */ node->tn_status |= TMPFS_NODE_CHANGED; tmpfs_update(vp); error = 0; out: return error; } /* --------------------------------------------------------------------- */ /* * We acquire all but fdvp locks using non-blocking acquisitions. If we * fail to acquire any lock in the path we will drop all held locks, * acquire the new lock in a blocking fashion, and then release it and * restart the rename. This acquire/release step ensures that we do not * spin on a lock waiting for release. On error release all vnode locks * and decrement references the way tmpfs_rename() would do. */ static int tmpfs_rename_relock(struct vnode *fdvp, struct vnode **fvpp, struct vnode *tdvp, struct vnode **tvpp, struct componentname *fcnp, struct componentname *tcnp) { struct vnode *nvp; struct mount *mp; struct tmpfs_dirent *de; int error, restarts = 0; VOP_UNLOCK(tdvp, 0); if (*tvpp != NULL && *tvpp != tdvp) VOP_UNLOCK(*tvpp, 0); mp = fdvp->v_mount; relock: restarts += 1; error = vn_lock(fdvp, LK_EXCLUSIVE); if (error) goto releout; if (vn_lock(tdvp, LK_EXCLUSIVE | LK_NOWAIT) != 0) { VOP_UNLOCK(fdvp, 0); error = vn_lock(tdvp, LK_EXCLUSIVE); if (error) goto releout; VOP_UNLOCK(tdvp, 0); goto relock; } /* * Re-resolve fvp to be certain it still exists and fetch the * correct vnode. */ de = tmpfs_dir_lookup(VP_TO_TMPFS_DIR(fdvp), NULL, fcnp); if (de == NULL) { VOP_UNLOCK(fdvp, 0); VOP_UNLOCK(tdvp, 0); if ((fcnp->cn_flags & ISDOTDOT) != 0 || (fcnp->cn_namelen == 1 && fcnp->cn_nameptr[0] == '.')) error = EINVAL; else error = ENOENT; goto releout; } error = tmpfs_alloc_vp(mp, de->td_node, LK_EXCLUSIVE | LK_NOWAIT, &nvp); if (error != 0) { VOP_UNLOCK(fdvp, 0); VOP_UNLOCK(tdvp, 0); if (error != EBUSY) goto releout; error = tmpfs_alloc_vp(mp, de->td_node, LK_EXCLUSIVE, &nvp); if (error != 0) goto releout; VOP_UNLOCK(nvp, 0); /* * Concurrent rename race. */ if (nvp == tdvp) { vrele(nvp); error = EINVAL; goto releout; } vrele(*fvpp); *fvpp = nvp; goto relock; } vrele(*fvpp); *fvpp = nvp; VOP_UNLOCK(*fvpp, 0); /* * Re-resolve tvp and acquire the vnode lock if present. */ de = tmpfs_dir_lookup(VP_TO_TMPFS_DIR(tdvp), NULL, tcnp); /* * If tvp disappeared we just carry on. */ if (de == NULL && *tvpp != NULL) { vrele(*tvpp); *tvpp = NULL; } /* * Get the tvp ino if the lookup succeeded. We may have to restart * if the non-blocking acquire fails. */ if (de != NULL) { nvp = NULL; error = tmpfs_alloc_vp(mp, de->td_node, LK_EXCLUSIVE | LK_NOWAIT, &nvp); if (*tvpp != NULL) vrele(*tvpp); *tvpp = nvp; if (error != 0) { VOP_UNLOCK(fdvp, 0); VOP_UNLOCK(tdvp, 0); if (error != EBUSY) goto releout; error = tmpfs_alloc_vp(mp, de->td_node, LK_EXCLUSIVE, &nvp); if (error != 0) goto releout; VOP_UNLOCK(nvp, 0); /* * fdvp contains fvp, thus tvp (=fdvp) is not empty. */ if (nvp == fdvp) { error = ENOTEMPTY; goto releout; } goto relock; } } tmpfs_rename_restarts += restarts; return (0); releout: vrele(fdvp); vrele(*fvpp); vrele(tdvp); if (*tvpp != NULL) vrele(*tvpp); tmpfs_rename_restarts += restarts; return (error); } static int tmpfs_rename(struct vop_rename_args *v) { struct vnode *fdvp = v->a_fdvp; struct vnode *fvp = v->a_fvp; struct componentname *fcnp = v->a_fcnp; struct vnode *tdvp = v->a_tdvp; struct vnode *tvp = v->a_tvp; struct componentname *tcnp = v->a_tcnp; struct mount *mp = NULL; char *newname; int error; struct tmpfs_dirent *de; struct tmpfs_mount *tmp; struct tmpfs_node *fdnode; struct tmpfs_node *fnode; struct tmpfs_node *tnode; struct tmpfs_node *tdnode; MPASS(VOP_ISLOCKED(tdvp)); MPASS(IMPLIES(tvp != NULL, VOP_ISLOCKED(tvp))); MPASS(fcnp->cn_flags & HASBUF); MPASS(tcnp->cn_flags & HASBUF); /* Disallow cross-device renames. * XXX Why isn't this done by the caller? */ if (fvp->v_mount != tdvp->v_mount || (tvp != NULL && fvp->v_mount != tvp->v_mount)) { error = EXDEV; goto out; } /* If source and target are the same file, there is nothing to do. */ if (fvp == tvp) { error = 0; goto out; } /* If we need to move the directory between entries, lock the * source so that we can safely operate on it. */ if (fdvp != tdvp && fdvp != tvp) { if (vn_lock(fdvp, LK_EXCLUSIVE | LK_NOWAIT) != 0) { mp = tdvp->v_mount; error = vfs_busy(mp, 0); if (error != 0) { mp = NULL; goto out; } error = tmpfs_rename_relock(fdvp, &fvp, tdvp, &tvp, fcnp, tcnp); if (error != 0) { vfs_unbusy(mp); return (error); } ASSERT_VOP_ELOCKED(fdvp, "tmpfs_rename: fdvp not locked"); ASSERT_VOP_ELOCKED(tdvp, "tmpfs_rename: tdvp not locked"); if (tvp != NULL) ASSERT_VOP_ELOCKED(tvp, "tmpfs_rename: tvp not locked"); if (fvp == tvp) { error = 0; goto out_locked; } } } tmp = VFS_TO_TMPFS(tdvp->v_mount); tdnode = VP_TO_TMPFS_DIR(tdvp); tnode = (tvp == NULL) ? NULL : VP_TO_TMPFS_NODE(tvp); fdnode = VP_TO_TMPFS_DIR(fdvp); fnode = VP_TO_TMPFS_NODE(fvp); de = tmpfs_dir_lookup(fdnode, fnode, fcnp); /* Entry can disappear before we lock fdvp, * also avoid manipulating '.' and '..' entries. */ if (de == NULL) { if ((fcnp->cn_flags & ISDOTDOT) != 0 || (fcnp->cn_namelen == 1 && fcnp->cn_nameptr[0] == '.')) error = EINVAL; else error = ENOENT; goto out_locked; } MPASS(de->td_node == fnode); /* If re-naming a directory to another preexisting directory * ensure that the target directory is empty so that its * removal causes no side effects. * Kern_rename gurantees the destination to be a directory * if the source is one. */ if (tvp != NULL) { MPASS(tnode != NULL); if ((tnode->tn_flags & (NOUNLINK | IMMUTABLE | APPEND)) || (tdnode->tn_flags & (APPEND | IMMUTABLE))) { error = EPERM; goto out_locked; } if (fnode->tn_type == VDIR && tnode->tn_type == VDIR) { if (tnode->tn_size > 0) { error = ENOTEMPTY; goto out_locked; } } else if (fnode->tn_type == VDIR && tnode->tn_type != VDIR) { error = ENOTDIR; goto out_locked; } else if (fnode->tn_type != VDIR && tnode->tn_type == VDIR) { error = EISDIR; goto out_locked; } else { MPASS(fnode->tn_type != VDIR && tnode->tn_type != VDIR); } } if ((fnode->tn_flags & (NOUNLINK | IMMUTABLE | APPEND)) || (fdnode->tn_flags & (APPEND | IMMUTABLE))) { error = EPERM; goto out_locked; } /* Ensure that we have enough memory to hold the new name, if it * has to be changed. */ if (fcnp->cn_namelen != tcnp->cn_namelen || bcmp(fcnp->cn_nameptr, tcnp->cn_nameptr, fcnp->cn_namelen) != 0) { newname = malloc(tcnp->cn_namelen, M_TMPFSNAME, M_WAITOK); } else newname = NULL; /* If the node is being moved to another directory, we have to do * the move. */ if (fdnode != tdnode) { /* In case we are moving a directory, we have to adjust its * parent to point to the new parent. */ if (de->td_node->tn_type == VDIR) { struct tmpfs_node *n; /* Ensure the target directory is not a child of the * directory being moved. Otherwise, we'd end up * with stale nodes. */ n = tdnode; /* TMPFS_LOCK garanties that no nodes are freed while * traversing the list. Nodes can only be marked as * removed: tn_parent == NULL. */ TMPFS_LOCK(tmp); TMPFS_NODE_LOCK(n); while (n != n->tn_dir.tn_parent) { struct tmpfs_node *parent; if (n == fnode) { TMPFS_NODE_UNLOCK(n); TMPFS_UNLOCK(tmp); error = EINVAL; if (newname != NULL) free(newname, M_TMPFSNAME); goto out_locked; } parent = n->tn_dir.tn_parent; TMPFS_NODE_UNLOCK(n); if (parent == NULL) { n = NULL; break; } TMPFS_NODE_LOCK(parent); if (parent->tn_dir.tn_parent == NULL) { TMPFS_NODE_UNLOCK(parent); n = NULL; break; } n = parent; } TMPFS_UNLOCK(tmp); if (n == NULL) { error = EINVAL; if (newname != NULL) free(newname, M_TMPFSNAME); goto out_locked; } TMPFS_NODE_UNLOCK(n); /* Adjust the parent pointer. */ TMPFS_VALIDATE_DIR(fnode); TMPFS_NODE_LOCK(de->td_node); de->td_node->tn_dir.tn_parent = tdnode; TMPFS_NODE_UNLOCK(de->td_node); /* As a result of changing the target of the '..' * entry, the link count of the source and target * directories has to be adjusted. */ TMPFS_NODE_LOCK(tdnode); TMPFS_ASSERT_LOCKED(tdnode); tdnode->tn_links++; TMPFS_NODE_UNLOCK(tdnode); TMPFS_NODE_LOCK(fdnode); TMPFS_ASSERT_LOCKED(fdnode); fdnode->tn_links--; TMPFS_NODE_UNLOCK(fdnode); } } /* Do the move: just remove the entry from the source directory * and insert it into the target one. */ tmpfs_dir_detach(fdvp, de); if (fcnp->cn_flags & DOWHITEOUT) tmpfs_dir_whiteout_add(fdvp, fcnp); if (tcnp->cn_flags & ISWHITEOUT) tmpfs_dir_whiteout_remove(tdvp, tcnp); /* If the name has changed, we need to make it effective by changing * it in the directory entry. */ if (newname != NULL) { MPASS(tcnp->cn_namelen <= MAXNAMLEN); free(de->ud.td_name, M_TMPFSNAME); de->ud.td_name = newname; tmpfs_dirent_init(de, tcnp->cn_nameptr, tcnp->cn_namelen); fnode->tn_status |= TMPFS_NODE_CHANGED; tdnode->tn_status |= TMPFS_NODE_MODIFIED; } /* If we are overwriting an entry, we have to remove the old one * from the target directory. */ if (tvp != NULL) { struct tmpfs_dirent *tde; /* Remove the old entry from the target directory. */ tde = tmpfs_dir_lookup(tdnode, tnode, tcnp); tmpfs_dir_detach(tdvp, tde); /* Free the directory entry we just deleted. Note that the * node referred by it will not be removed until the vnode is * really reclaimed. */ tmpfs_free_dirent(VFS_TO_TMPFS(tvp->v_mount), tde); } tmpfs_dir_attach(tdvp, de); cache_purge(fvp); if (tvp != NULL) cache_purge(tvp); cache_purge_negative(tdvp); error = 0; out_locked: if (fdvp != tdvp && fdvp != tvp) VOP_UNLOCK(fdvp, 0); out: /* Release target nodes. */ /* XXX: I don't understand when tdvp can be the same as tvp, but * other code takes care of this... */ if (tdvp == tvp) vrele(tdvp); else vput(tdvp); if (tvp != NULL) vput(tvp); /* Release source nodes. */ vrele(fdvp); vrele(fvp); if (mp != NULL) vfs_unbusy(mp); return error; } /* --------------------------------------------------------------------- */ static int tmpfs_mkdir(struct vop_mkdir_args *v) { struct vnode *dvp = v->a_dvp; struct vnode **vpp = v->a_vpp; struct componentname *cnp = v->a_cnp; struct vattr *vap = v->a_vap; MPASS(vap->va_type == VDIR); return tmpfs_alloc_file(dvp, vpp, vap, cnp, NULL); } /* --------------------------------------------------------------------- */ static int tmpfs_rmdir(struct vop_rmdir_args *v) { struct vnode *dvp = v->a_dvp; struct vnode *vp = v->a_vp; int error; struct tmpfs_dirent *de; struct tmpfs_mount *tmp; struct tmpfs_node *dnode; struct tmpfs_node *node; MPASS(VOP_ISLOCKED(dvp)); MPASS(VOP_ISLOCKED(vp)); tmp = VFS_TO_TMPFS(dvp->v_mount); dnode = VP_TO_TMPFS_DIR(dvp); node = VP_TO_TMPFS_DIR(vp); /* Directories with more than two entries ('.' and '..') cannot be * removed. */ if (node->tn_size > 0) { error = ENOTEMPTY; goto out; } if ((dnode->tn_flags & APPEND) || (node->tn_flags & (NOUNLINK | IMMUTABLE | APPEND))) { error = EPERM; goto out; } /* This invariant holds only if we are not trying to remove "..". * We checked for that above so this is safe now. */ MPASS(node->tn_dir.tn_parent == dnode); /* Get the directory entry associated with node (vp). This was * filled by tmpfs_lookup while looking up the entry. */ de = tmpfs_dir_lookup(dnode, node, v->a_cnp); MPASS(TMPFS_DIRENT_MATCHES(de, v->a_cnp->cn_nameptr, v->a_cnp->cn_namelen)); /* Check flags to see if we are allowed to remove the directory. */ if (dnode->tn_flags & APPEND || node->tn_flags & (NOUNLINK | IMMUTABLE | APPEND)) { error = EPERM; goto out; } /* Detach the directory entry from the directory (dnode). */ tmpfs_dir_detach(dvp, de); if (v->a_cnp->cn_flags & DOWHITEOUT) tmpfs_dir_whiteout_add(dvp, v->a_cnp); /* No vnode should be allocated for this entry from this point */ TMPFS_NODE_LOCK(node); TMPFS_ASSERT_ELOCKED(node); node->tn_links--; node->tn_dir.tn_parent = NULL; node->tn_status |= TMPFS_NODE_ACCESSED | TMPFS_NODE_CHANGED | \ TMPFS_NODE_MODIFIED; TMPFS_NODE_UNLOCK(node); TMPFS_NODE_LOCK(dnode); TMPFS_ASSERT_ELOCKED(dnode); dnode->tn_links--; dnode->tn_status |= TMPFS_NODE_ACCESSED | \ TMPFS_NODE_CHANGED | TMPFS_NODE_MODIFIED; TMPFS_NODE_UNLOCK(dnode); cache_purge(dvp); cache_purge(vp); /* Free the directory entry we just deleted. Note that the node * referred by it will not be removed until the vnode is really * reclaimed. */ tmpfs_free_dirent(tmp, de); /* Release the deleted vnode (will destroy the node, notify * interested parties and clean it from the cache). */ dnode->tn_status |= TMPFS_NODE_CHANGED; tmpfs_update(dvp); error = 0; out: return error; } /* --------------------------------------------------------------------- */ static int tmpfs_symlink(struct vop_symlink_args *v) { struct vnode *dvp = v->a_dvp; struct vnode **vpp = v->a_vpp; struct componentname *cnp = v->a_cnp; struct vattr *vap = v->a_vap; char *target = v->a_target; #ifdef notyet /* XXX FreeBSD BUG: kern_symlink is not setting VLNK */ MPASS(vap->va_type == VLNK); #else vap->va_type = VLNK; #endif return tmpfs_alloc_file(dvp, vpp, vap, cnp, target); } /* --------------------------------------------------------------------- */ static int tmpfs_readdir(struct vop_readdir_args *v) { struct vnode *vp = v->a_vp; struct uio *uio = v->a_uio; int *eofflag = v->a_eofflag; u_long **cookies = v->a_cookies; int *ncookies = v->a_ncookies; int error; ssize_t startresid; int cnt = 0; struct tmpfs_node *node; /* This operation only makes sense on directory nodes. */ if (vp->v_type != VDIR) return ENOTDIR; node = VP_TO_TMPFS_DIR(vp); startresid = uio->uio_resid; if (cookies != NULL && ncookies != NULL) { cnt = howmany(node->tn_size, sizeof(struct tmpfs_dirent)) + 2; *cookies = malloc(cnt * sizeof(**cookies), M_TEMP, M_WAITOK); *ncookies = 0; } if (cnt == 0) error = tmpfs_dir_getdents(node, uio, 0, NULL, NULL); else error = tmpfs_dir_getdents(node, uio, cnt, *cookies, ncookies); if (error == EJUSTRETURN) error = (uio->uio_resid != startresid) ? 0 : EINVAL; if (error != 0 && cnt != 0) free(*cookies, M_TEMP); if (eofflag != NULL) *eofflag = (error == 0 && uio->uio_offset == TMPFS_DIRCOOKIE_EOF); return error; } /* --------------------------------------------------------------------- */ static int tmpfs_readlink(struct vop_readlink_args *v) { struct vnode *vp = v->a_vp; struct uio *uio = v->a_uio; int error; struct tmpfs_node *node; MPASS(uio->uio_offset == 0); MPASS(vp->v_type == VLNK); node = VP_TO_TMPFS_NODE(vp); error = uiomove(node->tn_link, MIN(node->tn_size, uio->uio_resid), uio); node->tn_status |= TMPFS_NODE_ACCESSED; return error; } /* --------------------------------------------------------------------- */ static int tmpfs_inactive(struct vop_inactive_args *v) { struct vnode *vp = v->a_vp; struct tmpfs_node *node; MPASS(VOP_ISLOCKED(vp)); node = VP_TO_TMPFS_NODE(vp); if (node->tn_links == 0) vrecycle(vp); return 0; } /* --------------------------------------------------------------------- */ int tmpfs_reclaim(struct vop_reclaim_args *v) { struct vnode *vp = v->a_vp; struct tmpfs_mount *tmp; struct tmpfs_node *node; node = VP_TO_TMPFS_NODE(vp); tmp = VFS_TO_TMPFS(vp->v_mount); vnode_destroy_vobject(vp); cache_purge(vp); TMPFS_NODE_LOCK(node); TMPFS_ASSERT_ELOCKED(node); tmpfs_free_vp(vp); /* If the node referenced by this vnode was deleted by the user, * we must free its associated data structures (now that the vnode * is being reclaimed). */ if (node->tn_links == 0 && (node->tn_vpstate & TMPFS_VNODE_ALLOCATING) == 0) { node->tn_vpstate = TMPFS_VNODE_DOOMED; TMPFS_NODE_UNLOCK(node); tmpfs_free_node(tmp, node); } else TMPFS_NODE_UNLOCK(node); MPASS(vp->v_data == NULL); return 0; } /* --------------------------------------------------------------------- */ static int tmpfs_print(struct vop_print_args *v) { struct vnode *vp = v->a_vp; struct tmpfs_node *node; node = VP_TO_TMPFS_NODE(vp); printf("tag VT_TMPFS, tmpfs_node %p, flags 0x%x, links %d\n", node, node->tn_flags, node->tn_links); printf("\tmode 0%o, owner %d, group %d, size %jd, status 0x%x\n", node->tn_mode, node->tn_uid, node->tn_gid, (intmax_t)node->tn_size, node->tn_status); if (vp->v_type == VFIFO) fifo_printinfo(vp); printf("\n"); return 0; } /* --------------------------------------------------------------------- */ static int tmpfs_pathconf(struct vop_pathconf_args *v) { int name = v->a_name; register_t *retval = v->a_retval; int error; error = 0; switch (name) { case _PC_LINK_MAX: *retval = LINK_MAX; break; case _PC_NAME_MAX: *retval = NAME_MAX; break; case _PC_PATH_MAX: *retval = PATH_MAX; break; case _PC_PIPE_BUF: *retval = PIPE_BUF; break; case _PC_CHOWN_RESTRICTED: *retval = 1; break; case _PC_NO_TRUNC: *retval = 1; break; case _PC_SYNC_IO: *retval = 1; break; case _PC_FILESIZEBITS: *retval = 0; /* XXX Don't know which value should I return. */ break; default: error = EINVAL; } return error; } static int tmpfs_vptofh(struct vop_vptofh_args *ap) { struct tmpfs_fid *tfhp; struct tmpfs_node *node; tfhp = (struct tmpfs_fid *)ap->a_fhp; node = VP_TO_TMPFS_NODE(ap->a_vp); tfhp->tf_len = sizeof(struct tmpfs_fid); tfhp->tf_id = node->tn_id; tfhp->tf_gen = node->tn_gen; return (0); } static int tmpfs_whiteout(struct vop_whiteout_args *ap) { struct vnode *dvp = ap->a_dvp; struct componentname *cnp = ap->a_cnp; struct tmpfs_dirent *de; switch (ap->a_flags) { case LOOKUP: return (0); case CREATE: de = tmpfs_dir_lookup(VP_TO_TMPFS_DIR(dvp), NULL, cnp); if (de != NULL) return (de->td_node == NULL ? 0 : EEXIST); return (tmpfs_dir_whiteout_add(dvp, cnp)); case DELETE: tmpfs_dir_whiteout_remove(dvp, cnp); return (0); default: panic("tmpfs_whiteout: unknown op"); } } /* --------------------------------------------------------------------- */ /* * vnode operations vector used for files stored in a tmpfs file system. */ struct vop_vector tmpfs_vnodeop_entries = { .vop_default = &default_vnodeops, .vop_lookup = vfs_cache_lookup, .vop_cachedlookup = tmpfs_lookup, .vop_create = tmpfs_create, .vop_mknod = tmpfs_mknod, .vop_open = tmpfs_open, .vop_close = tmpfs_close, .vop_access = tmpfs_access, .vop_getattr = tmpfs_getattr, .vop_setattr = tmpfs_setattr, .vop_read = tmpfs_read, .vop_write = tmpfs_write, .vop_fsync = tmpfs_fsync, .vop_remove = tmpfs_remove, .vop_link = tmpfs_link, .vop_rename = tmpfs_rename, .vop_mkdir = tmpfs_mkdir, .vop_rmdir = tmpfs_rmdir, .vop_symlink = tmpfs_symlink, .vop_readdir = tmpfs_readdir, .vop_readlink = tmpfs_readlink, .vop_inactive = tmpfs_inactive, .vop_reclaim = tmpfs_reclaim, .vop_print = tmpfs_print, .vop_pathconf = tmpfs_pathconf, .vop_vptofh = tmpfs_vptofh, .vop_whiteout = tmpfs_whiteout, .vop_bmap = VOP_EOPNOTSUPP, };