3242 lines
81 KiB
C
3242 lines
81 KiB
C
/*-
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* SPDX-License-Identifier: BSD-3-Clause
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*
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* Copyright (c) 1982, 1986, 1989, 1993
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* The Regents of the University of California. All rights reserved.
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* (c) UNIX System Laboratories, Inc.
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* All or some portions of this file are derived from material licensed
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* to the University of California by American Telephone and Telegraph
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* Co. or Unix System Laboratories, Inc. and are reproduced herein with
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* the permission of UNIX System Laboratories, Inc.
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*
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* Copyright (c) 2012 Konstantin Belousov <kib@FreeBSD.org>
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* Copyright (c) 2013, 2014 The FreeBSD Foundation
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*
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* Portions of this software were developed by Konstantin Belousov
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* under sponsorship from the FreeBSD Foundation.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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* 3. Neither the name of the University nor the names of its contributors
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* may be used to endorse or promote products derived from this software
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* without specific prior written permission.
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*
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* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
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* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
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* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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* SUCH DAMAGE.
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*
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* @(#)vfs_vnops.c 8.2 (Berkeley) 1/21/94
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*/
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#include <sys/cdefs.h>
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__FBSDID("$FreeBSD$");
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#include "opt_hwpmc_hooks.h"
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#include <sys/param.h>
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#include <sys/systm.h>
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#include <sys/disk.h>
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#include <sys/fail.h>
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#include <sys/fcntl.h>
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#include <sys/file.h>
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#include <sys/kdb.h>
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#include <sys/ktr.h>
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#include <sys/stat.h>
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#include <sys/priv.h>
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#include <sys/proc.h>
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#include <sys/limits.h>
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#include <sys/lock.h>
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#include <sys/mman.h>
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#include <sys/mount.h>
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#include <sys/mutex.h>
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#include <sys/namei.h>
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#include <sys/vnode.h>
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#include <sys/bio.h>
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#include <sys/buf.h>
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#include <sys/filio.h>
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#include <sys/resourcevar.h>
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#include <sys/rwlock.h>
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#include <sys/sx.h>
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#include <sys/sleepqueue.h>
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#include <sys/sysctl.h>
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#include <sys/ttycom.h>
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#include <sys/conf.h>
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#include <sys/syslog.h>
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#include <sys/unistd.h>
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#include <sys/user.h>
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#include <security/audit/audit.h>
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#include <security/mac/mac_framework.h>
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#include <vm/vm.h>
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#include <vm/vm_extern.h>
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#include <vm/pmap.h>
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#include <vm/vm_map.h>
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#include <vm/vm_object.h>
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#include <vm/vm_page.h>
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#include <vm/vm_pager.h>
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#ifdef HWPMC_HOOKS
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#include <sys/pmckern.h>
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#endif
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static fo_rdwr_t vn_read;
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static fo_rdwr_t vn_write;
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static fo_rdwr_t vn_io_fault;
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static fo_truncate_t vn_truncate;
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static fo_ioctl_t vn_ioctl;
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static fo_poll_t vn_poll;
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static fo_kqfilter_t vn_kqfilter;
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static fo_stat_t vn_statfile;
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static fo_close_t vn_closefile;
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static fo_mmap_t vn_mmap;
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static fo_fallocate_t vn_fallocate;
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struct fileops vnops = {
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.fo_read = vn_io_fault,
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.fo_write = vn_io_fault,
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.fo_truncate = vn_truncate,
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.fo_ioctl = vn_ioctl,
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.fo_poll = vn_poll,
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.fo_kqfilter = vn_kqfilter,
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.fo_stat = vn_statfile,
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.fo_close = vn_closefile,
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.fo_chmod = vn_chmod,
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.fo_chown = vn_chown,
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.fo_sendfile = vn_sendfile,
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.fo_seek = vn_seek,
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.fo_fill_kinfo = vn_fill_kinfo,
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.fo_mmap = vn_mmap,
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.fo_fallocate = vn_fallocate,
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.fo_flags = DFLAG_PASSABLE | DFLAG_SEEKABLE
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};
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static const int io_hold_cnt = 16;
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static int vn_io_fault_enable = 1;
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SYSCTL_INT(_debug, OID_AUTO, vn_io_fault_enable, CTLFLAG_RW,
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&vn_io_fault_enable, 0, "Enable vn_io_fault lock avoidance");
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static int vn_io_fault_prefault = 0;
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SYSCTL_INT(_debug, OID_AUTO, vn_io_fault_prefault, CTLFLAG_RW,
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&vn_io_fault_prefault, 0, "Enable vn_io_fault prefaulting");
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static u_long vn_io_faults_cnt;
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SYSCTL_ULONG(_debug, OID_AUTO, vn_io_faults, CTLFLAG_RD,
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&vn_io_faults_cnt, 0, "Count of vn_io_fault lock avoidance triggers");
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/*
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* Returns true if vn_io_fault mode of handling the i/o request should
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* be used.
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*/
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static bool
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do_vn_io_fault(struct vnode *vp, struct uio *uio)
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{
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struct mount *mp;
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return (uio->uio_segflg == UIO_USERSPACE && vp->v_type == VREG &&
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(mp = vp->v_mount) != NULL &&
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(mp->mnt_kern_flag & MNTK_NO_IOPF) != 0 && vn_io_fault_enable);
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}
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/*
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* Structure used to pass arguments to vn_io_fault1(), to do either
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* file- or vnode-based I/O calls.
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*/
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struct vn_io_fault_args {
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enum {
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VN_IO_FAULT_FOP,
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VN_IO_FAULT_VOP
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} kind;
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struct ucred *cred;
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int flags;
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union {
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struct fop_args_tag {
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struct file *fp;
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fo_rdwr_t *doio;
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} fop_args;
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struct vop_args_tag {
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struct vnode *vp;
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} vop_args;
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} args;
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};
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static int vn_io_fault1(struct vnode *vp, struct uio *uio,
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struct vn_io_fault_args *args, struct thread *td);
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int
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vn_open(struct nameidata *ndp, int *flagp, int cmode, struct file *fp)
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{
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struct thread *td = ndp->ni_cnd.cn_thread;
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return (vn_open_cred(ndp, flagp, cmode, 0, td->td_ucred, fp));
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}
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/*
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* Common code for vnode open operations via a name lookup.
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* Lookup the vnode and invoke VOP_CREATE if needed.
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* Check permissions, and call the VOP_OPEN or VOP_CREATE routine.
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*
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* Note that this does NOT free nameidata for the successful case,
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* due to the NDINIT being done elsewhere.
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*/
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int
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vn_open_cred(struct nameidata *ndp, int *flagp, int cmode, u_int vn_open_flags,
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struct ucred *cred, struct file *fp)
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{
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struct vnode *vp;
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struct mount *mp;
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struct thread *td = ndp->ni_cnd.cn_thread;
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struct vattr vat;
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struct vattr *vap = &vat;
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int fmode, error;
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restart:
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fmode = *flagp;
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if ((fmode & (O_CREAT | O_EXCL | O_DIRECTORY)) == (O_CREAT |
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O_EXCL | O_DIRECTORY))
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return (EINVAL);
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else if ((fmode & (O_CREAT | O_DIRECTORY)) == O_CREAT) {
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ndp->ni_cnd.cn_nameiop = CREATE;
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/*
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* Set NOCACHE to avoid flushing the cache when
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* rolling in many files at once.
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*/
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ndp->ni_cnd.cn_flags = ISOPEN | LOCKPARENT | LOCKLEAF | NOCACHE;
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if ((fmode & O_EXCL) == 0 && (fmode & O_NOFOLLOW) == 0)
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ndp->ni_cnd.cn_flags |= FOLLOW;
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if ((fmode & O_BENEATH) != 0)
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ndp->ni_cnd.cn_flags |= BENEATH;
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if (!(vn_open_flags & VN_OPEN_NOAUDIT))
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ndp->ni_cnd.cn_flags |= AUDITVNODE1;
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if (vn_open_flags & VN_OPEN_NOCAPCHECK)
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ndp->ni_cnd.cn_flags |= NOCAPCHECK;
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if ((vn_open_flags & VN_OPEN_INVFS) == 0)
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bwillwrite();
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if ((error = namei(ndp)) != 0)
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return (error);
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if (ndp->ni_vp == NULL) {
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VATTR_NULL(vap);
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vap->va_type = VREG;
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vap->va_mode = cmode;
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if (fmode & O_EXCL)
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vap->va_vaflags |= VA_EXCLUSIVE;
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if (vn_start_write(ndp->ni_dvp, &mp, V_NOWAIT) != 0) {
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NDFREE(ndp, NDF_ONLY_PNBUF);
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vput(ndp->ni_dvp);
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if ((error = vn_start_write(NULL, &mp,
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V_XSLEEP | PCATCH)) != 0)
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return (error);
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goto restart;
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}
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if ((vn_open_flags & VN_OPEN_NAMECACHE) != 0)
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ndp->ni_cnd.cn_flags |= MAKEENTRY;
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#ifdef MAC
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error = mac_vnode_check_create(cred, ndp->ni_dvp,
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&ndp->ni_cnd, vap);
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if (error == 0)
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#endif
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error = VOP_CREATE(ndp->ni_dvp, &ndp->ni_vp,
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&ndp->ni_cnd, vap);
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vput(ndp->ni_dvp);
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vn_finished_write(mp);
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if (error) {
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NDFREE(ndp, NDF_ONLY_PNBUF);
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return (error);
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}
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fmode &= ~O_TRUNC;
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vp = ndp->ni_vp;
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} else {
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if (ndp->ni_dvp == ndp->ni_vp)
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vrele(ndp->ni_dvp);
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else
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vput(ndp->ni_dvp);
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ndp->ni_dvp = NULL;
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vp = ndp->ni_vp;
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if (fmode & O_EXCL) {
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error = EEXIST;
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goto bad;
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}
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if (vp->v_type == VDIR) {
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error = EISDIR;
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goto bad;
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}
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fmode &= ~O_CREAT;
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}
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} else {
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ndp->ni_cnd.cn_nameiop = LOOKUP;
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ndp->ni_cnd.cn_flags = ISOPEN |
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((fmode & O_NOFOLLOW) ? NOFOLLOW : FOLLOW) | LOCKLEAF;
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if (!(fmode & FWRITE))
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ndp->ni_cnd.cn_flags |= LOCKSHARED;
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if ((fmode & O_BENEATH) != 0)
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ndp->ni_cnd.cn_flags |= BENEATH;
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if (!(vn_open_flags & VN_OPEN_NOAUDIT))
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ndp->ni_cnd.cn_flags |= AUDITVNODE1;
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if (vn_open_flags & VN_OPEN_NOCAPCHECK)
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ndp->ni_cnd.cn_flags |= NOCAPCHECK;
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if ((error = namei(ndp)) != 0)
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return (error);
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vp = ndp->ni_vp;
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}
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error = vn_open_vnode(vp, fmode, cred, td, fp);
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if (error)
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goto bad;
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*flagp = fmode;
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return (0);
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bad:
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NDFREE(ndp, NDF_ONLY_PNBUF);
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vput(vp);
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*flagp = fmode;
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ndp->ni_vp = NULL;
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return (error);
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}
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static int
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vn_open_vnode_advlock(struct vnode *vp, int fmode, struct file *fp)
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{
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struct flock lf;
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int error, lock_flags, type;
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ASSERT_VOP_LOCKED(vp, "vn_open_vnode_advlock");
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if ((fmode & (O_EXLOCK | O_SHLOCK)) == 0)
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return (0);
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KASSERT(fp != NULL, ("open with flock requires fp"));
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if (fp->f_type != DTYPE_NONE && fp->f_type != DTYPE_VNODE)
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return (EOPNOTSUPP);
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lock_flags = VOP_ISLOCKED(vp);
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VOP_UNLOCK(vp);
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lf.l_whence = SEEK_SET;
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lf.l_start = 0;
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lf.l_len = 0;
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lf.l_type = (fmode & O_EXLOCK) != 0 ? F_WRLCK : F_RDLCK;
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type = F_FLOCK;
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if ((fmode & FNONBLOCK) == 0)
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type |= F_WAIT;
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error = VOP_ADVLOCK(vp, (caddr_t)fp, F_SETLK, &lf, type);
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if (error == 0)
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fp->f_flag |= FHASLOCK;
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vn_lock(vp, lock_flags | LK_RETRY);
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if (error == 0 && VN_IS_DOOMED(vp))
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error = ENOENT;
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return (error);
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}
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/*
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* Common code for vnode open operations once a vnode is located.
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* Check permissions, and call the VOP_OPEN routine.
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*/
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int
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vn_open_vnode(struct vnode *vp, int fmode, struct ucred *cred,
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struct thread *td, struct file *fp)
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{
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accmode_t accmode;
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int error;
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if (vp->v_type == VLNK)
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return (EMLINK);
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if (vp->v_type == VSOCK)
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return (EOPNOTSUPP);
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if (vp->v_type != VDIR && fmode & O_DIRECTORY)
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return (ENOTDIR);
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accmode = 0;
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if (fmode & (FWRITE | O_TRUNC)) {
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if (vp->v_type == VDIR)
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return (EISDIR);
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accmode |= VWRITE;
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}
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if (fmode & FREAD)
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accmode |= VREAD;
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if (fmode & FEXEC)
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accmode |= VEXEC;
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if ((fmode & O_APPEND) && (fmode & FWRITE))
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accmode |= VAPPEND;
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#ifdef MAC
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if (fmode & O_CREAT)
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accmode |= VCREAT;
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if (fmode & O_VERIFY)
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accmode |= VVERIFY;
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error = mac_vnode_check_open(cred, vp, accmode);
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if (error)
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return (error);
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|
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accmode &= ~(VCREAT | VVERIFY);
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#endif
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if ((fmode & O_CREAT) == 0 && accmode != 0) {
|
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error = VOP_ACCESS(vp, accmode, cred, td);
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if (error != 0)
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return (error);
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}
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if (vp->v_type == VFIFO && VOP_ISLOCKED(vp) != LK_EXCLUSIVE)
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vn_lock(vp, LK_UPGRADE | LK_RETRY);
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error = VOP_OPEN(vp, fmode, cred, td, fp);
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if (error != 0)
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return (error);
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|
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error = vn_open_vnode_advlock(vp, fmode, fp);
|
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if (error == 0 && (fmode & FWRITE) != 0) {
|
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error = VOP_ADD_WRITECOUNT(vp, 1);
|
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if (error == 0) {
|
|
CTR3(KTR_VFS, "%s: vp %p v_writecount increased to %d",
|
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__func__, vp, vp->v_writecount);
|
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}
|
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}
|
|
|
|
/*
|
|
* Error from advlock or VOP_ADD_WRITECOUNT() still requires
|
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* calling VOP_CLOSE() to pair with earlier VOP_OPEN().
|
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* Arrange for that by having fdrop() to use vn_closefile().
|
|
*/
|
|
if (error != 0) {
|
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fp->f_flag |= FOPENFAILED;
|
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fp->f_vnode = vp;
|
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if (fp->f_ops == &badfileops) {
|
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fp->f_type = DTYPE_VNODE;
|
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fp->f_ops = &vnops;
|
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}
|
|
vref(vp);
|
|
}
|
|
|
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ASSERT_VOP_LOCKED(vp, "vn_open_vnode");
|
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return (error);
|
|
|
|
}
|
|
|
|
/*
|
|
* Check for write permissions on the specified vnode.
|
|
* Prototype text segments cannot be written.
|
|
* It is racy.
|
|
*/
|
|
int
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vn_writechk(struct vnode *vp)
|
|
{
|
|
|
|
ASSERT_VOP_LOCKED(vp, "vn_writechk");
|
|
/*
|
|
* If there's shared text associated with
|
|
* the vnode, try to free it up once. If
|
|
* we fail, we can't allow writing.
|
|
*/
|
|
if (VOP_IS_TEXT(vp))
|
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return (ETXTBSY);
|
|
|
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return (0);
|
|
}
|
|
|
|
/*
|
|
* Vnode close call
|
|
*/
|
|
static int
|
|
vn_close1(struct vnode *vp, int flags, struct ucred *file_cred,
|
|
struct thread *td, bool keep_ref)
|
|
{
|
|
struct mount *mp;
|
|
int error, lock_flags;
|
|
|
|
if (vp->v_type != VFIFO && (flags & FWRITE) == 0 &&
|
|
MNT_EXTENDED_SHARED(vp->v_mount))
|
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lock_flags = LK_SHARED;
|
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else
|
|
lock_flags = LK_EXCLUSIVE;
|
|
|
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vn_start_write(vp, &mp, V_WAIT);
|
|
vn_lock(vp, lock_flags | LK_RETRY);
|
|
AUDIT_ARG_VNODE1(vp);
|
|
if ((flags & (FWRITE | FOPENFAILED)) == FWRITE) {
|
|
VOP_ADD_WRITECOUNT_CHECKED(vp, -1);
|
|
CTR3(KTR_VFS, "%s: vp %p v_writecount decreased to %d",
|
|
__func__, vp, vp->v_writecount);
|
|
}
|
|
error = VOP_CLOSE(vp, flags, file_cred, td);
|
|
if (keep_ref)
|
|
VOP_UNLOCK(vp);
|
|
else
|
|
vput(vp);
|
|
vn_finished_write(mp);
|
|
return (error);
|
|
}
|
|
|
|
int
|
|
vn_close(struct vnode *vp, int flags, struct ucred *file_cred,
|
|
struct thread *td)
|
|
{
|
|
|
|
return (vn_close1(vp, flags, file_cred, td, false));
|
|
}
|
|
|
|
/*
|
|
* Heuristic to detect sequential operation.
|
|
*/
|
|
static int
|
|
sequential_heuristic(struct uio *uio, struct file *fp)
|
|
{
|
|
|
|
ASSERT_VOP_LOCKED(fp->f_vnode, __func__);
|
|
if (fp->f_flag & FRDAHEAD)
|
|
return (fp->f_seqcount << IO_SEQSHIFT);
|
|
|
|
/*
|
|
* Offset 0 is handled specially. open() sets f_seqcount to 1 so
|
|
* that the first I/O is normally considered to be slightly
|
|
* sequential. Seeking to offset 0 doesn't change sequentiality
|
|
* unless previous seeks have reduced f_seqcount to 0, in which
|
|
* case offset 0 is not special.
|
|
*/
|
|
if ((uio->uio_offset == 0 && fp->f_seqcount > 0) ||
|
|
uio->uio_offset == fp->f_nextoff) {
|
|
/*
|
|
* f_seqcount is in units of fixed-size blocks so that it
|
|
* depends mainly on the amount of sequential I/O and not
|
|
* much on the number of sequential I/O's. The fixed size
|
|
* of 16384 is hard-coded here since it is (not quite) just
|
|
* a magic size that works well here. This size is more
|
|
* closely related to the best I/O size for real disks than
|
|
* to any block size used by software.
|
|
*/
|
|
if (uio->uio_resid >= IO_SEQMAX * 16384)
|
|
fp->f_seqcount = IO_SEQMAX;
|
|
else {
|
|
fp->f_seqcount += howmany(uio->uio_resid, 16384);
|
|
if (fp->f_seqcount > IO_SEQMAX)
|
|
fp->f_seqcount = IO_SEQMAX;
|
|
}
|
|
return (fp->f_seqcount << IO_SEQSHIFT);
|
|
}
|
|
|
|
/* Not sequential. Quickly draw-down sequentiality. */
|
|
if (fp->f_seqcount > 1)
|
|
fp->f_seqcount = 1;
|
|
else
|
|
fp->f_seqcount = 0;
|
|
return (0);
|
|
}
|
|
|
|
/*
|
|
* Package up an I/O request on a vnode into a uio and do it.
|
|
*/
|
|
int
|
|
vn_rdwr(enum uio_rw rw, struct vnode *vp, void *base, int len, off_t offset,
|
|
enum uio_seg segflg, int ioflg, struct ucred *active_cred,
|
|
struct ucred *file_cred, ssize_t *aresid, struct thread *td)
|
|
{
|
|
struct uio auio;
|
|
struct iovec aiov;
|
|
struct mount *mp;
|
|
struct ucred *cred;
|
|
void *rl_cookie;
|
|
struct vn_io_fault_args args;
|
|
int error, lock_flags;
|
|
|
|
if (offset < 0 && vp->v_type != VCHR)
|
|
return (EINVAL);
|
|
auio.uio_iov = &aiov;
|
|
auio.uio_iovcnt = 1;
|
|
aiov.iov_base = base;
|
|
aiov.iov_len = len;
|
|
auio.uio_resid = len;
|
|
auio.uio_offset = offset;
|
|
auio.uio_segflg = segflg;
|
|
auio.uio_rw = rw;
|
|
auio.uio_td = td;
|
|
error = 0;
|
|
|
|
if ((ioflg & IO_NODELOCKED) == 0) {
|
|
if ((ioflg & IO_RANGELOCKED) == 0) {
|
|
if (rw == UIO_READ) {
|
|
rl_cookie = vn_rangelock_rlock(vp, offset,
|
|
offset + len);
|
|
} else {
|
|
rl_cookie = vn_rangelock_wlock(vp, offset,
|
|
offset + len);
|
|
}
|
|
} else
|
|
rl_cookie = NULL;
|
|
mp = NULL;
|
|
if (rw == UIO_WRITE) {
|
|
if (vp->v_type != VCHR &&
|
|
(error = vn_start_write(vp, &mp, V_WAIT | PCATCH))
|
|
!= 0)
|
|
goto out;
|
|
if (MNT_SHARED_WRITES(mp) ||
|
|
((mp == NULL) && MNT_SHARED_WRITES(vp->v_mount)))
|
|
lock_flags = LK_SHARED;
|
|
else
|
|
lock_flags = LK_EXCLUSIVE;
|
|
} else
|
|
lock_flags = LK_SHARED;
|
|
vn_lock(vp, lock_flags | LK_RETRY);
|
|
} else
|
|
rl_cookie = NULL;
|
|
|
|
ASSERT_VOP_LOCKED(vp, "IO_NODELOCKED with no vp lock held");
|
|
#ifdef MAC
|
|
if ((ioflg & IO_NOMACCHECK) == 0) {
|
|
if (rw == UIO_READ)
|
|
error = mac_vnode_check_read(active_cred, file_cred,
|
|
vp);
|
|
else
|
|
error = mac_vnode_check_write(active_cred, file_cred,
|
|
vp);
|
|
}
|
|
#endif
|
|
if (error == 0) {
|
|
if (file_cred != NULL)
|
|
cred = file_cred;
|
|
else
|
|
cred = active_cred;
|
|
if (do_vn_io_fault(vp, &auio)) {
|
|
args.kind = VN_IO_FAULT_VOP;
|
|
args.cred = cred;
|
|
args.flags = ioflg;
|
|
args.args.vop_args.vp = vp;
|
|
error = vn_io_fault1(vp, &auio, &args, td);
|
|
} else if (rw == UIO_READ) {
|
|
error = VOP_READ(vp, &auio, ioflg, cred);
|
|
} else /* if (rw == UIO_WRITE) */ {
|
|
error = VOP_WRITE(vp, &auio, ioflg, cred);
|
|
}
|
|
}
|
|
if (aresid)
|
|
*aresid = auio.uio_resid;
|
|
else
|
|
if (auio.uio_resid && error == 0)
|
|
error = EIO;
|
|
if ((ioflg & IO_NODELOCKED) == 0) {
|
|
VOP_UNLOCK(vp);
|
|
if (mp != NULL)
|
|
vn_finished_write(mp);
|
|
}
|
|
out:
|
|
if (rl_cookie != NULL)
|
|
vn_rangelock_unlock(vp, rl_cookie);
|
|
return (error);
|
|
}
|
|
|
|
/*
|
|
* Package up an I/O request on a vnode into a uio and do it. The I/O
|
|
* request is split up into smaller chunks and we try to avoid saturating
|
|
* the buffer cache while potentially holding a vnode locked, so we
|
|
* check bwillwrite() before calling vn_rdwr(). We also call kern_yield()
|
|
* to give other processes a chance to lock the vnode (either other processes
|
|
* core'ing the same binary, or unrelated processes scanning the directory).
|
|
*/
|
|
int
|
|
vn_rdwr_inchunks(enum uio_rw rw, struct vnode *vp, void *base, size_t len,
|
|
off_t offset, enum uio_seg segflg, int ioflg, struct ucred *active_cred,
|
|
struct ucred *file_cred, size_t *aresid, struct thread *td)
|
|
{
|
|
int error = 0;
|
|
ssize_t iaresid;
|
|
|
|
do {
|
|
int chunk;
|
|
|
|
/*
|
|
* Force `offset' to a multiple of MAXBSIZE except possibly
|
|
* for the first chunk, so that filesystems only need to
|
|
* write full blocks except possibly for the first and last
|
|
* chunks.
|
|
*/
|
|
chunk = MAXBSIZE - (uoff_t)offset % MAXBSIZE;
|
|
|
|
if (chunk > len)
|
|
chunk = len;
|
|
if (rw != UIO_READ && vp->v_type == VREG)
|
|
bwillwrite();
|
|
iaresid = 0;
|
|
error = vn_rdwr(rw, vp, base, chunk, offset, segflg,
|
|
ioflg, active_cred, file_cred, &iaresid, td);
|
|
len -= chunk; /* aresid calc already includes length */
|
|
if (error)
|
|
break;
|
|
offset += chunk;
|
|
base = (char *)base + chunk;
|
|
kern_yield(PRI_USER);
|
|
} while (len);
|
|
if (aresid)
|
|
*aresid = len + iaresid;
|
|
return (error);
|
|
}
|
|
|
|
#if OFF_MAX <= LONG_MAX
|
|
off_t
|
|
foffset_lock(struct file *fp, int flags)
|
|
{
|
|
volatile short *flagsp;
|
|
off_t res;
|
|
short state;
|
|
|
|
KASSERT((flags & FOF_OFFSET) == 0, ("FOF_OFFSET passed"));
|
|
|
|
if ((flags & FOF_NOLOCK) != 0)
|
|
return (atomic_load_long(&fp->f_offset));
|
|
|
|
/*
|
|
* According to McKusick the vn lock was protecting f_offset here.
|
|
* It is now protected by the FOFFSET_LOCKED flag.
|
|
*/
|
|
flagsp = &fp->f_vnread_flags;
|
|
if (atomic_cmpset_acq_16(flagsp, 0, FOFFSET_LOCKED))
|
|
return (atomic_load_long(&fp->f_offset));
|
|
|
|
sleepq_lock(&fp->f_vnread_flags);
|
|
state = atomic_load_16(flagsp);
|
|
for (;;) {
|
|
if ((state & FOFFSET_LOCKED) == 0) {
|
|
if (!atomic_fcmpset_acq_16(flagsp, &state,
|
|
FOFFSET_LOCKED))
|
|
continue;
|
|
break;
|
|
}
|
|
if ((state & FOFFSET_LOCK_WAITING) == 0) {
|
|
if (!atomic_fcmpset_acq_16(flagsp, &state,
|
|
state | FOFFSET_LOCK_WAITING))
|
|
continue;
|
|
}
|
|
DROP_GIANT();
|
|
sleepq_add(&fp->f_vnread_flags, NULL, "vofflock", 0, 0);
|
|
sleepq_wait(&fp->f_vnread_flags, PUSER -1);
|
|
PICKUP_GIANT();
|
|
sleepq_lock(&fp->f_vnread_flags);
|
|
state = atomic_load_16(flagsp);
|
|
}
|
|
res = atomic_load_long(&fp->f_offset);
|
|
sleepq_release(&fp->f_vnread_flags);
|
|
return (res);
|
|
}
|
|
|
|
void
|
|
foffset_unlock(struct file *fp, off_t val, int flags)
|
|
{
|
|
volatile short *flagsp;
|
|
short state;
|
|
|
|
KASSERT((flags & FOF_OFFSET) == 0, ("FOF_OFFSET passed"));
|
|
|
|
if ((flags & FOF_NOUPDATE) == 0)
|
|
atomic_store_long(&fp->f_offset, val);
|
|
if ((flags & FOF_NEXTOFF) != 0)
|
|
fp->f_nextoff = val;
|
|
|
|
if ((flags & FOF_NOLOCK) != 0)
|
|
return;
|
|
|
|
flagsp = &fp->f_vnread_flags;
|
|
state = atomic_load_16(flagsp);
|
|
if ((state & FOFFSET_LOCK_WAITING) == 0 &&
|
|
atomic_cmpset_rel_16(flagsp, state, 0))
|
|
return;
|
|
|
|
sleepq_lock(&fp->f_vnread_flags);
|
|
MPASS((fp->f_vnread_flags & FOFFSET_LOCKED) != 0);
|
|
MPASS((fp->f_vnread_flags & FOFFSET_LOCK_WAITING) != 0);
|
|
fp->f_vnread_flags = 0;
|
|
sleepq_broadcast(&fp->f_vnread_flags, SLEEPQ_SLEEP, 0, 0);
|
|
sleepq_release(&fp->f_vnread_flags);
|
|
}
|
|
#else
|
|
off_t
|
|
foffset_lock(struct file *fp, int flags)
|
|
{
|
|
struct mtx *mtxp;
|
|
off_t res;
|
|
|
|
KASSERT((flags & FOF_OFFSET) == 0, ("FOF_OFFSET passed"));
|
|
|
|
mtxp = mtx_pool_find(mtxpool_sleep, fp);
|
|
mtx_lock(mtxp);
|
|
if ((flags & FOF_NOLOCK) == 0) {
|
|
while (fp->f_vnread_flags & FOFFSET_LOCKED) {
|
|
fp->f_vnread_flags |= FOFFSET_LOCK_WAITING;
|
|
msleep(&fp->f_vnread_flags, mtxp, PUSER -1,
|
|
"vofflock", 0);
|
|
}
|
|
fp->f_vnread_flags |= FOFFSET_LOCKED;
|
|
}
|
|
res = fp->f_offset;
|
|
mtx_unlock(mtxp);
|
|
return (res);
|
|
}
|
|
|
|
void
|
|
foffset_unlock(struct file *fp, off_t val, int flags)
|
|
{
|
|
struct mtx *mtxp;
|
|
|
|
KASSERT((flags & FOF_OFFSET) == 0, ("FOF_OFFSET passed"));
|
|
|
|
mtxp = mtx_pool_find(mtxpool_sleep, fp);
|
|
mtx_lock(mtxp);
|
|
if ((flags & FOF_NOUPDATE) == 0)
|
|
fp->f_offset = val;
|
|
if ((flags & FOF_NEXTOFF) != 0)
|
|
fp->f_nextoff = val;
|
|
if ((flags & FOF_NOLOCK) == 0) {
|
|
KASSERT((fp->f_vnread_flags & FOFFSET_LOCKED) != 0,
|
|
("Lost FOFFSET_LOCKED"));
|
|
if (fp->f_vnread_flags & FOFFSET_LOCK_WAITING)
|
|
wakeup(&fp->f_vnread_flags);
|
|
fp->f_vnread_flags = 0;
|
|
}
|
|
mtx_unlock(mtxp);
|
|
}
|
|
#endif
|
|
|
|
void
|
|
foffset_lock_uio(struct file *fp, struct uio *uio, int flags)
|
|
{
|
|
|
|
if ((flags & FOF_OFFSET) == 0)
|
|
uio->uio_offset = foffset_lock(fp, flags);
|
|
}
|
|
|
|
void
|
|
foffset_unlock_uio(struct file *fp, struct uio *uio, int flags)
|
|
{
|
|
|
|
if ((flags & FOF_OFFSET) == 0)
|
|
foffset_unlock(fp, uio->uio_offset, flags);
|
|
}
|
|
|
|
static int
|
|
get_advice(struct file *fp, struct uio *uio)
|
|
{
|
|
struct mtx *mtxp;
|
|
int ret;
|
|
|
|
ret = POSIX_FADV_NORMAL;
|
|
if (fp->f_advice == NULL || fp->f_vnode->v_type != VREG)
|
|
return (ret);
|
|
|
|
mtxp = mtx_pool_find(mtxpool_sleep, fp);
|
|
mtx_lock(mtxp);
|
|
if (fp->f_advice != NULL &&
|
|
uio->uio_offset >= fp->f_advice->fa_start &&
|
|
uio->uio_offset + uio->uio_resid <= fp->f_advice->fa_end)
|
|
ret = fp->f_advice->fa_advice;
|
|
mtx_unlock(mtxp);
|
|
return (ret);
|
|
}
|
|
|
|
/*
|
|
* File table vnode read routine.
|
|
*/
|
|
static int
|
|
vn_read(struct file *fp, struct uio *uio, struct ucred *active_cred, int flags,
|
|
struct thread *td)
|
|
{
|
|
struct vnode *vp;
|
|
off_t orig_offset;
|
|
int error, ioflag;
|
|
int advice;
|
|
|
|
KASSERT(uio->uio_td == td, ("uio_td %p is not td %p",
|
|
uio->uio_td, td));
|
|
KASSERT(flags & FOF_OFFSET, ("No FOF_OFFSET"));
|
|
vp = fp->f_vnode;
|
|
ioflag = 0;
|
|
if (fp->f_flag & FNONBLOCK)
|
|
ioflag |= IO_NDELAY;
|
|
if (fp->f_flag & O_DIRECT)
|
|
ioflag |= IO_DIRECT;
|
|
advice = get_advice(fp, uio);
|
|
vn_lock(vp, LK_SHARED | LK_RETRY);
|
|
|
|
switch (advice) {
|
|
case POSIX_FADV_NORMAL:
|
|
case POSIX_FADV_SEQUENTIAL:
|
|
case POSIX_FADV_NOREUSE:
|
|
ioflag |= sequential_heuristic(uio, fp);
|
|
break;
|
|
case POSIX_FADV_RANDOM:
|
|
/* Disable read-ahead for random I/O. */
|
|
break;
|
|
}
|
|
orig_offset = uio->uio_offset;
|
|
|
|
#ifdef MAC
|
|
error = mac_vnode_check_read(active_cred, fp->f_cred, vp);
|
|
if (error == 0)
|
|
#endif
|
|
error = VOP_READ(vp, uio, ioflag, fp->f_cred);
|
|
fp->f_nextoff = uio->uio_offset;
|
|
VOP_UNLOCK(vp);
|
|
if (error == 0 && advice == POSIX_FADV_NOREUSE &&
|
|
orig_offset != uio->uio_offset)
|
|
/*
|
|
* Use POSIX_FADV_DONTNEED to flush pages and buffers
|
|
* for the backing file after a POSIX_FADV_NOREUSE
|
|
* read(2).
|
|
*/
|
|
error = VOP_ADVISE(vp, orig_offset, uio->uio_offset - 1,
|
|
POSIX_FADV_DONTNEED);
|
|
return (error);
|
|
}
|
|
|
|
/*
|
|
* File table vnode write routine.
|
|
*/
|
|
static int
|
|
vn_write(struct file *fp, struct uio *uio, struct ucred *active_cred, int flags,
|
|
struct thread *td)
|
|
{
|
|
struct vnode *vp;
|
|
struct mount *mp;
|
|
off_t orig_offset;
|
|
int error, ioflag, lock_flags;
|
|
int advice;
|
|
|
|
KASSERT(uio->uio_td == td, ("uio_td %p is not td %p",
|
|
uio->uio_td, td));
|
|
KASSERT(flags & FOF_OFFSET, ("No FOF_OFFSET"));
|
|
vp = fp->f_vnode;
|
|
if (vp->v_type == VREG)
|
|
bwillwrite();
|
|
ioflag = IO_UNIT;
|
|
if (vp->v_type == VREG && (fp->f_flag & O_APPEND))
|
|
ioflag |= IO_APPEND;
|
|
if (fp->f_flag & FNONBLOCK)
|
|
ioflag |= IO_NDELAY;
|
|
if (fp->f_flag & O_DIRECT)
|
|
ioflag |= IO_DIRECT;
|
|
if ((fp->f_flag & O_FSYNC) ||
|
|
(vp->v_mount && (vp->v_mount->mnt_flag & MNT_SYNCHRONOUS)))
|
|
ioflag |= IO_SYNC;
|
|
mp = NULL;
|
|
if (vp->v_type != VCHR &&
|
|
(error = vn_start_write(vp, &mp, V_WAIT | PCATCH)) != 0)
|
|
goto unlock;
|
|
|
|
advice = get_advice(fp, uio);
|
|
|
|
if (MNT_SHARED_WRITES(mp) ||
|
|
(mp == NULL && MNT_SHARED_WRITES(vp->v_mount))) {
|
|
lock_flags = LK_SHARED;
|
|
} else {
|
|
lock_flags = LK_EXCLUSIVE;
|
|
}
|
|
|
|
vn_lock(vp, lock_flags | LK_RETRY);
|
|
switch (advice) {
|
|
case POSIX_FADV_NORMAL:
|
|
case POSIX_FADV_SEQUENTIAL:
|
|
case POSIX_FADV_NOREUSE:
|
|
ioflag |= sequential_heuristic(uio, fp);
|
|
break;
|
|
case POSIX_FADV_RANDOM:
|
|
/* XXX: Is this correct? */
|
|
break;
|
|
}
|
|
orig_offset = uio->uio_offset;
|
|
|
|
#ifdef MAC
|
|
error = mac_vnode_check_write(active_cred, fp->f_cred, vp);
|
|
if (error == 0)
|
|
#endif
|
|
error = VOP_WRITE(vp, uio, ioflag, fp->f_cred);
|
|
fp->f_nextoff = uio->uio_offset;
|
|
VOP_UNLOCK(vp);
|
|
if (vp->v_type != VCHR)
|
|
vn_finished_write(mp);
|
|
if (error == 0 && advice == POSIX_FADV_NOREUSE &&
|
|
orig_offset != uio->uio_offset)
|
|
/*
|
|
* Use POSIX_FADV_DONTNEED to flush pages and buffers
|
|
* for the backing file after a POSIX_FADV_NOREUSE
|
|
* write(2).
|
|
*/
|
|
error = VOP_ADVISE(vp, orig_offset, uio->uio_offset - 1,
|
|
POSIX_FADV_DONTNEED);
|
|
unlock:
|
|
return (error);
|
|
}
|
|
|
|
/*
|
|
* The vn_io_fault() is a wrapper around vn_read() and vn_write() to
|
|
* prevent the following deadlock:
|
|
*
|
|
* Assume that the thread A reads from the vnode vp1 into userspace
|
|
* buffer buf1 backed by the pages of vnode vp2. If a page in buf1 is
|
|
* currently not resident, then system ends up with the call chain
|
|
* vn_read() -> VOP_READ(vp1) -> uiomove() -> [Page Fault] ->
|
|
* vm_fault(buf1) -> vnode_pager_getpages(vp2) -> VOP_GETPAGES(vp2)
|
|
* which establishes lock order vp1->vn_lock, then vp2->vn_lock.
|
|
* If, at the same time, thread B reads from vnode vp2 into buffer buf2
|
|
* backed by the pages of vnode vp1, and some page in buf2 is not
|
|
* resident, we get a reversed order vp2->vn_lock, then vp1->vn_lock.
|
|
*
|
|
* To prevent the lock order reversal and deadlock, vn_io_fault() does
|
|
* not allow page faults to happen during VOP_READ() or VOP_WRITE().
|
|
* Instead, it first tries to do the whole range i/o with pagefaults
|
|
* disabled. If all pages in the i/o buffer are resident and mapped,
|
|
* VOP will succeed (ignoring the genuine filesystem errors).
|
|
* Otherwise, we get back EFAULT, and vn_io_fault() falls back to do
|
|
* i/o in chunks, with all pages in the chunk prefaulted and held
|
|
* using vm_fault_quick_hold_pages().
|
|
*
|
|
* Filesystems using this deadlock avoidance scheme should use the
|
|
* array of the held pages from uio, saved in the curthread->td_ma,
|
|
* instead of doing uiomove(). A helper function
|
|
* vn_io_fault_uiomove() converts uiomove request into
|
|
* uiomove_fromphys() over td_ma array.
|
|
*
|
|
* Since vnode locks do not cover the whole i/o anymore, rangelocks
|
|
* make the current i/o request atomic with respect to other i/os and
|
|
* truncations.
|
|
*/
|
|
|
|
/*
|
|
* Decode vn_io_fault_args and perform the corresponding i/o.
|
|
*/
|
|
static int
|
|
vn_io_fault_doio(struct vn_io_fault_args *args, struct uio *uio,
|
|
struct thread *td)
|
|
{
|
|
int error, save;
|
|
|
|
error = 0;
|
|
save = vm_fault_disable_pagefaults();
|
|
switch (args->kind) {
|
|
case VN_IO_FAULT_FOP:
|
|
error = (args->args.fop_args.doio)(args->args.fop_args.fp,
|
|
uio, args->cred, args->flags, td);
|
|
break;
|
|
case VN_IO_FAULT_VOP:
|
|
if (uio->uio_rw == UIO_READ) {
|
|
error = VOP_READ(args->args.vop_args.vp, uio,
|
|
args->flags, args->cred);
|
|
} else if (uio->uio_rw == UIO_WRITE) {
|
|
error = VOP_WRITE(args->args.vop_args.vp, uio,
|
|
args->flags, args->cred);
|
|
}
|
|
break;
|
|
default:
|
|
panic("vn_io_fault_doio: unknown kind of io %d %d",
|
|
args->kind, uio->uio_rw);
|
|
}
|
|
vm_fault_enable_pagefaults(save);
|
|
return (error);
|
|
}
|
|
|
|
static int
|
|
vn_io_fault_touch(char *base, const struct uio *uio)
|
|
{
|
|
int r;
|
|
|
|
r = fubyte(base);
|
|
if (r == -1 || (uio->uio_rw == UIO_READ && subyte(base, r) == -1))
|
|
return (EFAULT);
|
|
return (0);
|
|
}
|
|
|
|
static int
|
|
vn_io_fault_prefault_user(const struct uio *uio)
|
|
{
|
|
char *base;
|
|
const struct iovec *iov;
|
|
size_t len;
|
|
ssize_t resid;
|
|
int error, i;
|
|
|
|
KASSERT(uio->uio_segflg == UIO_USERSPACE,
|
|
("vn_io_fault_prefault userspace"));
|
|
|
|
error = i = 0;
|
|
iov = uio->uio_iov;
|
|
resid = uio->uio_resid;
|
|
base = iov->iov_base;
|
|
len = iov->iov_len;
|
|
while (resid > 0) {
|
|
error = vn_io_fault_touch(base, uio);
|
|
if (error != 0)
|
|
break;
|
|
if (len < PAGE_SIZE) {
|
|
if (len != 0) {
|
|
error = vn_io_fault_touch(base + len - 1, uio);
|
|
if (error != 0)
|
|
break;
|
|
resid -= len;
|
|
}
|
|
if (++i >= uio->uio_iovcnt)
|
|
break;
|
|
iov = uio->uio_iov + i;
|
|
base = iov->iov_base;
|
|
len = iov->iov_len;
|
|
} else {
|
|
len -= PAGE_SIZE;
|
|
base += PAGE_SIZE;
|
|
resid -= PAGE_SIZE;
|
|
}
|
|
}
|
|
return (error);
|
|
}
|
|
|
|
/*
|
|
* Common code for vn_io_fault(), agnostic to the kind of i/o request.
|
|
* Uses vn_io_fault_doio() to make the call to an actual i/o function.
|
|
* Used from vn_rdwr() and vn_io_fault(), which encode the i/o request
|
|
* into args and call vn_io_fault1() to handle faults during the user
|
|
* mode buffer accesses.
|
|
*/
|
|
static int
|
|
vn_io_fault1(struct vnode *vp, struct uio *uio, struct vn_io_fault_args *args,
|
|
struct thread *td)
|
|
{
|
|
vm_page_t ma[io_hold_cnt + 2];
|
|
struct uio *uio_clone, short_uio;
|
|
struct iovec short_iovec[1];
|
|
vm_page_t *prev_td_ma;
|
|
vm_prot_t prot;
|
|
vm_offset_t addr, end;
|
|
size_t len, resid;
|
|
ssize_t adv;
|
|
int error, cnt, saveheld, prev_td_ma_cnt;
|
|
|
|
if (vn_io_fault_prefault) {
|
|
error = vn_io_fault_prefault_user(uio);
|
|
if (error != 0)
|
|
return (error); /* Or ignore ? */
|
|
}
|
|
|
|
prot = uio->uio_rw == UIO_READ ? VM_PROT_WRITE : VM_PROT_READ;
|
|
|
|
/*
|
|
* The UFS follows IO_UNIT directive and replays back both
|
|
* uio_offset and uio_resid if an error is encountered during the
|
|
* operation. But, since the iovec may be already advanced,
|
|
* uio is still in an inconsistent state.
|
|
*
|
|
* Cache a copy of the original uio, which is advanced to the redo
|
|
* point using UIO_NOCOPY below.
|
|
*/
|
|
uio_clone = cloneuio(uio);
|
|
resid = uio->uio_resid;
|
|
|
|
short_uio.uio_segflg = UIO_USERSPACE;
|
|
short_uio.uio_rw = uio->uio_rw;
|
|
short_uio.uio_td = uio->uio_td;
|
|
|
|
error = vn_io_fault_doio(args, uio, td);
|
|
if (error != EFAULT)
|
|
goto out;
|
|
|
|
atomic_add_long(&vn_io_faults_cnt, 1);
|
|
uio_clone->uio_segflg = UIO_NOCOPY;
|
|
uiomove(NULL, resid - uio->uio_resid, uio_clone);
|
|
uio_clone->uio_segflg = uio->uio_segflg;
|
|
|
|
saveheld = curthread_pflags_set(TDP_UIOHELD);
|
|
prev_td_ma = td->td_ma;
|
|
prev_td_ma_cnt = td->td_ma_cnt;
|
|
|
|
while (uio_clone->uio_resid != 0) {
|
|
len = uio_clone->uio_iov->iov_len;
|
|
if (len == 0) {
|
|
KASSERT(uio_clone->uio_iovcnt >= 1,
|
|
("iovcnt underflow"));
|
|
uio_clone->uio_iov++;
|
|
uio_clone->uio_iovcnt--;
|
|
continue;
|
|
}
|
|
if (len > io_hold_cnt * PAGE_SIZE)
|
|
len = io_hold_cnt * PAGE_SIZE;
|
|
addr = (uintptr_t)uio_clone->uio_iov->iov_base;
|
|
end = round_page(addr + len);
|
|
if (end < addr) {
|
|
error = EFAULT;
|
|
break;
|
|
}
|
|
cnt = atop(end - trunc_page(addr));
|
|
/*
|
|
* A perfectly misaligned address and length could cause
|
|
* both the start and the end of the chunk to use partial
|
|
* page. +2 accounts for such a situation.
|
|
*/
|
|
cnt = vm_fault_quick_hold_pages(&td->td_proc->p_vmspace->vm_map,
|
|
addr, len, prot, ma, io_hold_cnt + 2);
|
|
if (cnt == -1) {
|
|
error = EFAULT;
|
|
break;
|
|
}
|
|
short_uio.uio_iov = &short_iovec[0];
|
|
short_iovec[0].iov_base = (void *)addr;
|
|
short_uio.uio_iovcnt = 1;
|
|
short_uio.uio_resid = short_iovec[0].iov_len = len;
|
|
short_uio.uio_offset = uio_clone->uio_offset;
|
|
td->td_ma = ma;
|
|
td->td_ma_cnt = cnt;
|
|
|
|
error = vn_io_fault_doio(args, &short_uio, td);
|
|
vm_page_unhold_pages(ma, cnt);
|
|
adv = len - short_uio.uio_resid;
|
|
|
|
uio_clone->uio_iov->iov_base =
|
|
(char *)uio_clone->uio_iov->iov_base + adv;
|
|
uio_clone->uio_iov->iov_len -= adv;
|
|
uio_clone->uio_resid -= adv;
|
|
uio_clone->uio_offset += adv;
|
|
|
|
uio->uio_resid -= adv;
|
|
uio->uio_offset += adv;
|
|
|
|
if (error != 0 || adv == 0)
|
|
break;
|
|
}
|
|
td->td_ma = prev_td_ma;
|
|
td->td_ma_cnt = prev_td_ma_cnt;
|
|
curthread_pflags_restore(saveheld);
|
|
out:
|
|
free(uio_clone, M_IOV);
|
|
return (error);
|
|
}
|
|
|
|
static int
|
|
vn_io_fault(struct file *fp, struct uio *uio, struct ucred *active_cred,
|
|
int flags, struct thread *td)
|
|
{
|
|
fo_rdwr_t *doio;
|
|
struct vnode *vp;
|
|
void *rl_cookie;
|
|
struct vn_io_fault_args args;
|
|
int error;
|
|
|
|
doio = uio->uio_rw == UIO_READ ? vn_read : vn_write;
|
|
vp = fp->f_vnode;
|
|
foffset_lock_uio(fp, uio, flags);
|
|
if (do_vn_io_fault(vp, uio)) {
|
|
args.kind = VN_IO_FAULT_FOP;
|
|
args.args.fop_args.fp = fp;
|
|
args.args.fop_args.doio = doio;
|
|
args.cred = active_cred;
|
|
args.flags = flags | FOF_OFFSET;
|
|
if (uio->uio_rw == UIO_READ) {
|
|
rl_cookie = vn_rangelock_rlock(vp, uio->uio_offset,
|
|
uio->uio_offset + uio->uio_resid);
|
|
} else if ((fp->f_flag & O_APPEND) != 0 ||
|
|
(flags & FOF_OFFSET) == 0) {
|
|
/* For appenders, punt and lock the whole range. */
|
|
rl_cookie = vn_rangelock_wlock(vp, 0, OFF_MAX);
|
|
} else {
|
|
rl_cookie = vn_rangelock_wlock(vp, uio->uio_offset,
|
|
uio->uio_offset + uio->uio_resid);
|
|
}
|
|
error = vn_io_fault1(vp, uio, &args, td);
|
|
vn_rangelock_unlock(vp, rl_cookie);
|
|
} else {
|
|
error = doio(fp, uio, active_cred, flags | FOF_OFFSET, td);
|
|
}
|
|
foffset_unlock_uio(fp, uio, flags);
|
|
return (error);
|
|
}
|
|
|
|
/*
|
|
* Helper function to perform the requested uiomove operation using
|
|
* the held pages for io->uio_iov[0].iov_base buffer instead of
|
|
* copyin/copyout. Access to the pages with uiomove_fromphys()
|
|
* instead of iov_base prevents page faults that could occur due to
|
|
* pmap_collect() invalidating the mapping created by
|
|
* vm_fault_quick_hold_pages(), or pageout daemon, page laundry or
|
|
* object cleanup revoking the write access from page mappings.
|
|
*
|
|
* Filesystems specified MNTK_NO_IOPF shall use vn_io_fault_uiomove()
|
|
* instead of plain uiomove().
|
|
*/
|
|
int
|
|
vn_io_fault_uiomove(char *data, int xfersize, struct uio *uio)
|
|
{
|
|
struct uio transp_uio;
|
|
struct iovec transp_iov[1];
|
|
struct thread *td;
|
|
size_t adv;
|
|
int error, pgadv;
|
|
|
|
td = curthread;
|
|
if ((td->td_pflags & TDP_UIOHELD) == 0 ||
|
|
uio->uio_segflg != UIO_USERSPACE)
|
|
return (uiomove(data, xfersize, uio));
|
|
|
|
KASSERT(uio->uio_iovcnt == 1, ("uio_iovcnt %d", uio->uio_iovcnt));
|
|
transp_iov[0].iov_base = data;
|
|
transp_uio.uio_iov = &transp_iov[0];
|
|
transp_uio.uio_iovcnt = 1;
|
|
if (xfersize > uio->uio_resid)
|
|
xfersize = uio->uio_resid;
|
|
transp_uio.uio_resid = transp_iov[0].iov_len = xfersize;
|
|
transp_uio.uio_offset = 0;
|
|
transp_uio.uio_segflg = UIO_SYSSPACE;
|
|
/*
|
|
* Since transp_iov points to data, and td_ma page array
|
|
* corresponds to original uio->uio_iov, we need to invert the
|
|
* direction of the i/o operation as passed to
|
|
* uiomove_fromphys().
|
|
*/
|
|
switch (uio->uio_rw) {
|
|
case UIO_WRITE:
|
|
transp_uio.uio_rw = UIO_READ;
|
|
break;
|
|
case UIO_READ:
|
|
transp_uio.uio_rw = UIO_WRITE;
|
|
break;
|
|
}
|
|
transp_uio.uio_td = uio->uio_td;
|
|
error = uiomove_fromphys(td->td_ma,
|
|
((vm_offset_t)uio->uio_iov->iov_base) & PAGE_MASK,
|
|
xfersize, &transp_uio);
|
|
adv = xfersize - transp_uio.uio_resid;
|
|
pgadv =
|
|
(((vm_offset_t)uio->uio_iov->iov_base + adv) >> PAGE_SHIFT) -
|
|
(((vm_offset_t)uio->uio_iov->iov_base) >> PAGE_SHIFT);
|
|
td->td_ma += pgadv;
|
|
KASSERT(td->td_ma_cnt >= pgadv, ("consumed pages %d %d", td->td_ma_cnt,
|
|
pgadv));
|
|
td->td_ma_cnt -= pgadv;
|
|
uio->uio_iov->iov_base = (char *)uio->uio_iov->iov_base + adv;
|
|
uio->uio_iov->iov_len -= adv;
|
|
uio->uio_resid -= adv;
|
|
uio->uio_offset += adv;
|
|
return (error);
|
|
}
|
|
|
|
int
|
|
vn_io_fault_pgmove(vm_page_t ma[], vm_offset_t offset, int xfersize,
|
|
struct uio *uio)
|
|
{
|
|
struct thread *td;
|
|
vm_offset_t iov_base;
|
|
int cnt, pgadv;
|
|
|
|
td = curthread;
|
|
if ((td->td_pflags & TDP_UIOHELD) == 0 ||
|
|
uio->uio_segflg != UIO_USERSPACE)
|
|
return (uiomove_fromphys(ma, offset, xfersize, uio));
|
|
|
|
KASSERT(uio->uio_iovcnt == 1, ("uio_iovcnt %d", uio->uio_iovcnt));
|
|
cnt = xfersize > uio->uio_resid ? uio->uio_resid : xfersize;
|
|
iov_base = (vm_offset_t)uio->uio_iov->iov_base;
|
|
switch (uio->uio_rw) {
|
|
case UIO_WRITE:
|
|
pmap_copy_pages(td->td_ma, iov_base & PAGE_MASK, ma,
|
|
offset, cnt);
|
|
break;
|
|
case UIO_READ:
|
|
pmap_copy_pages(ma, offset, td->td_ma, iov_base & PAGE_MASK,
|
|
cnt);
|
|
break;
|
|
}
|
|
pgadv = ((iov_base + cnt) >> PAGE_SHIFT) - (iov_base >> PAGE_SHIFT);
|
|
td->td_ma += pgadv;
|
|
KASSERT(td->td_ma_cnt >= pgadv, ("consumed pages %d %d", td->td_ma_cnt,
|
|
pgadv));
|
|
td->td_ma_cnt -= pgadv;
|
|
uio->uio_iov->iov_base = (char *)(iov_base + cnt);
|
|
uio->uio_iov->iov_len -= cnt;
|
|
uio->uio_resid -= cnt;
|
|
uio->uio_offset += cnt;
|
|
return (0);
|
|
}
|
|
|
|
/*
|
|
* File table truncate routine.
|
|
*/
|
|
static int
|
|
vn_truncate(struct file *fp, off_t length, struct ucred *active_cred,
|
|
struct thread *td)
|
|
{
|
|
struct mount *mp;
|
|
struct vnode *vp;
|
|
void *rl_cookie;
|
|
int error;
|
|
|
|
vp = fp->f_vnode;
|
|
|
|
/*
|
|
* Lock the whole range for truncation. Otherwise split i/o
|
|
* might happen partly before and partly after the truncation.
|
|
*/
|
|
rl_cookie = vn_rangelock_wlock(vp, 0, OFF_MAX);
|
|
error = vn_start_write(vp, &mp, V_WAIT | PCATCH);
|
|
if (error)
|
|
goto out1;
|
|
vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
|
|
AUDIT_ARG_VNODE1(vp);
|
|
if (vp->v_type == VDIR) {
|
|
error = EISDIR;
|
|
goto out;
|
|
}
|
|
#ifdef MAC
|
|
error = mac_vnode_check_write(active_cred, fp->f_cred, vp);
|
|
if (error)
|
|
goto out;
|
|
#endif
|
|
error = vn_truncate_locked(vp, length, (fp->f_flag & O_FSYNC) != 0,
|
|
fp->f_cred);
|
|
out:
|
|
VOP_UNLOCK(vp);
|
|
vn_finished_write(mp);
|
|
out1:
|
|
vn_rangelock_unlock(vp, rl_cookie);
|
|
return (error);
|
|
}
|
|
|
|
/*
|
|
* Truncate a file that is already locked.
|
|
*/
|
|
int
|
|
vn_truncate_locked(struct vnode *vp, off_t length, bool sync,
|
|
struct ucred *cred)
|
|
{
|
|
struct vattr vattr;
|
|
int error;
|
|
|
|
error = VOP_ADD_WRITECOUNT(vp, 1);
|
|
if (error == 0) {
|
|
VATTR_NULL(&vattr);
|
|
vattr.va_size = length;
|
|
if (sync)
|
|
vattr.va_vaflags |= VA_SYNC;
|
|
error = VOP_SETATTR(vp, &vattr, cred);
|
|
VOP_ADD_WRITECOUNT_CHECKED(vp, -1);
|
|
}
|
|
return (error);
|
|
}
|
|
|
|
/*
|
|
* File table vnode stat routine.
|
|
*/
|
|
static int
|
|
vn_statfile(struct file *fp, struct stat *sb, struct ucred *active_cred,
|
|
struct thread *td)
|
|
{
|
|
struct vnode *vp = fp->f_vnode;
|
|
int error;
|
|
|
|
vn_lock(vp, LK_SHARED | LK_RETRY);
|
|
error = vn_stat(vp, sb, active_cred, fp->f_cred, td);
|
|
VOP_UNLOCK(vp);
|
|
|
|
return (error);
|
|
}
|
|
|
|
/*
|
|
* Stat a vnode; implementation for the stat syscall
|
|
*/
|
|
int
|
|
vn_stat(struct vnode *vp, struct stat *sb, struct ucred *active_cred,
|
|
struct ucred *file_cred, struct thread *td)
|
|
{
|
|
struct vattr vattr;
|
|
struct vattr *vap;
|
|
int error;
|
|
u_short mode;
|
|
|
|
AUDIT_ARG_VNODE1(vp);
|
|
#ifdef MAC
|
|
error = mac_vnode_check_stat(active_cred, file_cred, vp);
|
|
if (error)
|
|
return (error);
|
|
#endif
|
|
|
|
vap = &vattr;
|
|
|
|
/*
|
|
* Initialize defaults for new and unusual fields, so that file
|
|
* systems which don't support these fields don't need to know
|
|
* about them.
|
|
*/
|
|
vap->va_birthtime.tv_sec = -1;
|
|
vap->va_birthtime.tv_nsec = 0;
|
|
vap->va_fsid = VNOVAL;
|
|
vap->va_rdev = NODEV;
|
|
|
|
error = VOP_GETATTR(vp, vap, active_cred);
|
|
if (error)
|
|
return (error);
|
|
|
|
/*
|
|
* Zero the spare stat fields
|
|
*/
|
|
bzero(sb, sizeof *sb);
|
|
|
|
/*
|
|
* Copy from vattr table
|
|
*/
|
|
if (vap->va_fsid != VNOVAL)
|
|
sb->st_dev = vap->va_fsid;
|
|
else
|
|
sb->st_dev = vp->v_mount->mnt_stat.f_fsid.val[0];
|
|
sb->st_ino = vap->va_fileid;
|
|
mode = vap->va_mode;
|
|
switch (vap->va_type) {
|
|
case VREG:
|
|
mode |= S_IFREG;
|
|
break;
|
|
case VDIR:
|
|
mode |= S_IFDIR;
|
|
break;
|
|
case VBLK:
|
|
mode |= S_IFBLK;
|
|
break;
|
|
case VCHR:
|
|
mode |= S_IFCHR;
|
|
break;
|
|
case VLNK:
|
|
mode |= S_IFLNK;
|
|
break;
|
|
case VSOCK:
|
|
mode |= S_IFSOCK;
|
|
break;
|
|
case VFIFO:
|
|
mode |= S_IFIFO;
|
|
break;
|
|
default:
|
|
return (EBADF);
|
|
}
|
|
sb->st_mode = mode;
|
|
sb->st_nlink = vap->va_nlink;
|
|
sb->st_uid = vap->va_uid;
|
|
sb->st_gid = vap->va_gid;
|
|
sb->st_rdev = vap->va_rdev;
|
|
if (vap->va_size > OFF_MAX)
|
|
return (EOVERFLOW);
|
|
sb->st_size = vap->va_size;
|
|
sb->st_atim.tv_sec = vap->va_atime.tv_sec;
|
|
sb->st_atim.tv_nsec = vap->va_atime.tv_nsec;
|
|
sb->st_mtim.tv_sec = vap->va_mtime.tv_sec;
|
|
sb->st_mtim.tv_nsec = vap->va_mtime.tv_nsec;
|
|
sb->st_ctim.tv_sec = vap->va_ctime.tv_sec;
|
|
sb->st_ctim.tv_nsec = vap->va_ctime.tv_nsec;
|
|
sb->st_birthtim.tv_sec = vap->va_birthtime.tv_sec;
|
|
sb->st_birthtim.tv_nsec = vap->va_birthtime.tv_nsec;
|
|
|
|
/*
|
|
* According to www.opengroup.org, the meaning of st_blksize is
|
|
* "a filesystem-specific preferred I/O block size for this
|
|
* object. In some filesystem types, this may vary from file
|
|
* to file"
|
|
* Use miminum/default of PAGE_SIZE (e.g. for VCHR).
|
|
*/
|
|
|
|
sb->st_blksize = max(PAGE_SIZE, vap->va_blocksize);
|
|
|
|
sb->st_flags = vap->va_flags;
|
|
if (priv_check_cred_vfs_generation(td->td_ucred))
|
|
sb->st_gen = 0;
|
|
else
|
|
sb->st_gen = vap->va_gen;
|
|
|
|
sb->st_blocks = vap->va_bytes / S_BLKSIZE;
|
|
return (0);
|
|
}
|
|
|
|
/*
|
|
* File table vnode ioctl routine.
|
|
*/
|
|
static int
|
|
vn_ioctl(struct file *fp, u_long com, void *data, struct ucred *active_cred,
|
|
struct thread *td)
|
|
{
|
|
struct vattr vattr;
|
|
struct vnode *vp;
|
|
struct fiobmap2_arg *bmarg;
|
|
int error;
|
|
|
|
vp = fp->f_vnode;
|
|
switch (vp->v_type) {
|
|
case VDIR:
|
|
case VREG:
|
|
switch (com) {
|
|
case FIONREAD:
|
|
vn_lock(vp, LK_SHARED | LK_RETRY);
|
|
error = VOP_GETATTR(vp, &vattr, active_cred);
|
|
VOP_UNLOCK(vp);
|
|
if (error == 0)
|
|
*(int *)data = vattr.va_size - fp->f_offset;
|
|
return (error);
|
|
case FIOBMAP2:
|
|
bmarg = (struct fiobmap2_arg *)data;
|
|
vn_lock(vp, LK_SHARED | LK_RETRY);
|
|
#ifdef MAC
|
|
error = mac_vnode_check_read(active_cred, fp->f_cred,
|
|
vp);
|
|
if (error == 0)
|
|
#endif
|
|
error = VOP_BMAP(vp, bmarg->bn, NULL,
|
|
&bmarg->bn, &bmarg->runp, &bmarg->runb);
|
|
VOP_UNLOCK(vp);
|
|
return (error);
|
|
case FIONBIO:
|
|
case FIOASYNC:
|
|
return (0);
|
|
default:
|
|
return (VOP_IOCTL(vp, com, data, fp->f_flag,
|
|
active_cred, td));
|
|
}
|
|
break;
|
|
case VCHR:
|
|
return (VOP_IOCTL(vp, com, data, fp->f_flag,
|
|
active_cred, td));
|
|
default:
|
|
return (ENOTTY);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* File table vnode poll routine.
|
|
*/
|
|
static int
|
|
vn_poll(struct file *fp, int events, struct ucred *active_cred,
|
|
struct thread *td)
|
|
{
|
|
struct vnode *vp;
|
|
int error;
|
|
|
|
vp = fp->f_vnode;
|
|
#ifdef MAC
|
|
vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
|
|
AUDIT_ARG_VNODE1(vp);
|
|
error = mac_vnode_check_poll(active_cred, fp->f_cred, vp);
|
|
VOP_UNLOCK(vp);
|
|
if (!error)
|
|
#endif
|
|
|
|
error = VOP_POLL(vp, events, fp->f_cred, td);
|
|
return (error);
|
|
}
|
|
|
|
/*
|
|
* Acquire the requested lock and then check for validity. LK_RETRY
|
|
* permits vn_lock to return doomed vnodes.
|
|
*/
|
|
static int __noinline
|
|
_vn_lock_fallback(struct vnode *vp, int flags, const char *file, int line,
|
|
int error)
|
|
{
|
|
|
|
KASSERT((flags & LK_RETRY) == 0 || error == 0,
|
|
("vn_lock: error %d incompatible with flags %#x", error, flags));
|
|
|
|
if (error == 0)
|
|
VNASSERT(VN_IS_DOOMED(vp), vp, ("vnode not doomed"));
|
|
|
|
if ((flags & LK_RETRY) == 0) {
|
|
if (error == 0) {
|
|
VOP_UNLOCK(vp);
|
|
error = ENOENT;
|
|
}
|
|
return (error);
|
|
}
|
|
|
|
/*
|
|
* LK_RETRY case.
|
|
*
|
|
* Nothing to do if we got the lock.
|
|
*/
|
|
if (error == 0)
|
|
return (0);
|
|
|
|
/*
|
|
* Interlock was dropped by the call in _vn_lock.
|
|
*/
|
|
flags &= ~LK_INTERLOCK;
|
|
do {
|
|
error = VOP_LOCK1(vp, flags, file, line);
|
|
} while (error != 0);
|
|
return (0);
|
|
}
|
|
|
|
int
|
|
_vn_lock(struct vnode *vp, int flags, const char *file, int line)
|
|
{
|
|
int error;
|
|
|
|
VNASSERT((flags & LK_TYPE_MASK) != 0, vp,
|
|
("vn_lock: no locktype (%d passed)", flags));
|
|
VNPASS(vp->v_holdcnt > 0, vp);
|
|
error = VOP_LOCK1(vp, flags, file, line);
|
|
if (__predict_false(error != 0 || VN_IS_DOOMED(vp)))
|
|
return (_vn_lock_fallback(vp, flags, file, line, error));
|
|
return (0);
|
|
}
|
|
|
|
/*
|
|
* File table vnode close routine.
|
|
*/
|
|
static int
|
|
vn_closefile(struct file *fp, struct thread *td)
|
|
{
|
|
struct vnode *vp;
|
|
struct flock lf;
|
|
int error;
|
|
bool ref;
|
|
|
|
vp = fp->f_vnode;
|
|
fp->f_ops = &badfileops;
|
|
ref= (fp->f_flag & FHASLOCK) != 0 && fp->f_type == DTYPE_VNODE;
|
|
|
|
error = vn_close1(vp, fp->f_flag, fp->f_cred, td, ref);
|
|
|
|
if (__predict_false(ref)) {
|
|
lf.l_whence = SEEK_SET;
|
|
lf.l_start = 0;
|
|
lf.l_len = 0;
|
|
lf.l_type = F_UNLCK;
|
|
(void) VOP_ADVLOCK(vp, fp, F_UNLCK, &lf, F_FLOCK);
|
|
vrele(vp);
|
|
}
|
|
return (error);
|
|
}
|
|
|
|
/*
|
|
* Preparing to start a filesystem write operation. If the operation is
|
|
* permitted, then we bump the count of operations in progress and
|
|
* proceed. If a suspend request is in progress, we wait until the
|
|
* suspension is over, and then proceed.
|
|
*/
|
|
static int
|
|
vn_start_write_refed(struct mount *mp, int flags, bool mplocked)
|
|
{
|
|
int error, mflags;
|
|
|
|
if (__predict_true(!mplocked) && (flags & V_XSLEEP) == 0 &&
|
|
vfs_op_thread_enter(mp)) {
|
|
MPASS((mp->mnt_kern_flag & MNTK_SUSPEND) == 0);
|
|
vfs_mp_count_add_pcpu(mp, writeopcount, 1);
|
|
vfs_op_thread_exit(mp);
|
|
return (0);
|
|
}
|
|
|
|
if (mplocked)
|
|
mtx_assert(MNT_MTX(mp), MA_OWNED);
|
|
else
|
|
MNT_ILOCK(mp);
|
|
|
|
error = 0;
|
|
|
|
/*
|
|
* Check on status of suspension.
|
|
*/
|
|
if ((curthread->td_pflags & TDP_IGNSUSP) == 0 ||
|
|
mp->mnt_susp_owner != curthread) {
|
|
mflags = ((mp->mnt_vfc->vfc_flags & VFCF_SBDRY) != 0 ?
|
|
(flags & PCATCH) : 0) | (PUSER - 1);
|
|
while ((mp->mnt_kern_flag & MNTK_SUSPEND) != 0) {
|
|
if (flags & V_NOWAIT) {
|
|
error = EWOULDBLOCK;
|
|
goto unlock;
|
|
}
|
|
error = msleep(&mp->mnt_flag, MNT_MTX(mp), mflags,
|
|
"suspfs", 0);
|
|
if (error)
|
|
goto unlock;
|
|
}
|
|
}
|
|
if (flags & V_XSLEEP)
|
|
goto unlock;
|
|
mp->mnt_writeopcount++;
|
|
unlock:
|
|
if (error != 0 || (flags & V_XSLEEP) != 0)
|
|
MNT_REL(mp);
|
|
MNT_IUNLOCK(mp);
|
|
return (error);
|
|
}
|
|
|
|
int
|
|
vn_start_write(struct vnode *vp, struct mount **mpp, int flags)
|
|
{
|
|
struct mount *mp;
|
|
int error;
|
|
|
|
KASSERT((flags & V_MNTREF) == 0 || (*mpp != NULL && vp == NULL),
|
|
("V_MNTREF requires mp"));
|
|
|
|
error = 0;
|
|
/*
|
|
* If a vnode is provided, get and return the mount point that
|
|
* to which it will write.
|
|
*/
|
|
if (vp != NULL) {
|
|
if ((error = VOP_GETWRITEMOUNT(vp, mpp)) != 0) {
|
|
*mpp = NULL;
|
|
if (error != EOPNOTSUPP)
|
|
return (error);
|
|
return (0);
|
|
}
|
|
}
|
|
if ((mp = *mpp) == NULL)
|
|
return (0);
|
|
|
|
/*
|
|
* VOP_GETWRITEMOUNT() returns with the mp refcount held through
|
|
* a vfs_ref().
|
|
* As long as a vnode is not provided we need to acquire a
|
|
* refcount for the provided mountpoint too, in order to
|
|
* emulate a vfs_ref().
|
|
*/
|
|
if (vp == NULL && (flags & V_MNTREF) == 0)
|
|
vfs_ref(mp);
|
|
|
|
return (vn_start_write_refed(mp, flags, false));
|
|
}
|
|
|
|
/*
|
|
* Secondary suspension. Used by operations such as vop_inactive
|
|
* routines that are needed by the higher level functions. These
|
|
* are allowed to proceed until all the higher level functions have
|
|
* completed (indicated by mnt_writeopcount dropping to zero). At that
|
|
* time, these operations are halted until the suspension is over.
|
|
*/
|
|
int
|
|
vn_start_secondary_write(struct vnode *vp, struct mount **mpp, int flags)
|
|
{
|
|
struct mount *mp;
|
|
int error;
|
|
|
|
KASSERT((flags & V_MNTREF) == 0 || (*mpp != NULL && vp == NULL),
|
|
("V_MNTREF requires mp"));
|
|
|
|
retry:
|
|
if (vp != NULL) {
|
|
if ((error = VOP_GETWRITEMOUNT(vp, mpp)) != 0) {
|
|
*mpp = NULL;
|
|
if (error != EOPNOTSUPP)
|
|
return (error);
|
|
return (0);
|
|
}
|
|
}
|
|
/*
|
|
* If we are not suspended or have not yet reached suspended
|
|
* mode, then let the operation proceed.
|
|
*/
|
|
if ((mp = *mpp) == NULL)
|
|
return (0);
|
|
|
|
/*
|
|
* VOP_GETWRITEMOUNT() returns with the mp refcount held through
|
|
* a vfs_ref().
|
|
* As long as a vnode is not provided we need to acquire a
|
|
* refcount for the provided mountpoint too, in order to
|
|
* emulate a vfs_ref().
|
|
*/
|
|
MNT_ILOCK(mp);
|
|
if (vp == NULL && (flags & V_MNTREF) == 0)
|
|
MNT_REF(mp);
|
|
if ((mp->mnt_kern_flag & (MNTK_SUSPENDED | MNTK_SUSPEND2)) == 0) {
|
|
mp->mnt_secondary_writes++;
|
|
mp->mnt_secondary_accwrites++;
|
|
MNT_IUNLOCK(mp);
|
|
return (0);
|
|
}
|
|
if (flags & V_NOWAIT) {
|
|
MNT_REL(mp);
|
|
MNT_IUNLOCK(mp);
|
|
return (EWOULDBLOCK);
|
|
}
|
|
/*
|
|
* Wait for the suspension to finish.
|
|
*/
|
|
error = msleep(&mp->mnt_flag, MNT_MTX(mp), (PUSER - 1) | PDROP |
|
|
((mp->mnt_vfc->vfc_flags & VFCF_SBDRY) != 0 ? (flags & PCATCH) : 0),
|
|
"suspfs", 0);
|
|
vfs_rel(mp);
|
|
if (error == 0)
|
|
goto retry;
|
|
return (error);
|
|
}
|
|
|
|
/*
|
|
* Filesystem write operation has completed. If we are suspending and this
|
|
* operation is the last one, notify the suspender that the suspension is
|
|
* now in effect.
|
|
*/
|
|
void
|
|
vn_finished_write(struct mount *mp)
|
|
{
|
|
int c;
|
|
|
|
if (mp == NULL)
|
|
return;
|
|
|
|
if (vfs_op_thread_enter(mp)) {
|
|
vfs_mp_count_sub_pcpu(mp, writeopcount, 1);
|
|
vfs_mp_count_sub_pcpu(mp, ref, 1);
|
|
vfs_op_thread_exit(mp);
|
|
return;
|
|
}
|
|
|
|
MNT_ILOCK(mp);
|
|
vfs_assert_mount_counters(mp);
|
|
MNT_REL(mp);
|
|
c = --mp->mnt_writeopcount;
|
|
if (mp->mnt_vfs_ops == 0) {
|
|
MPASS((mp->mnt_kern_flag & MNTK_SUSPEND) == 0);
|
|
MNT_IUNLOCK(mp);
|
|
return;
|
|
}
|
|
if (c < 0)
|
|
vfs_dump_mount_counters(mp);
|
|
if ((mp->mnt_kern_flag & MNTK_SUSPEND) != 0 && c == 0)
|
|
wakeup(&mp->mnt_writeopcount);
|
|
MNT_IUNLOCK(mp);
|
|
}
|
|
|
|
/*
|
|
* Filesystem secondary write operation has completed. If we are
|
|
* suspending and this operation is the last one, notify the suspender
|
|
* that the suspension is now in effect.
|
|
*/
|
|
void
|
|
vn_finished_secondary_write(struct mount *mp)
|
|
{
|
|
if (mp == NULL)
|
|
return;
|
|
MNT_ILOCK(mp);
|
|
MNT_REL(mp);
|
|
mp->mnt_secondary_writes--;
|
|
if (mp->mnt_secondary_writes < 0)
|
|
panic("vn_finished_secondary_write: neg cnt");
|
|
if ((mp->mnt_kern_flag & MNTK_SUSPEND) != 0 &&
|
|
mp->mnt_secondary_writes <= 0)
|
|
wakeup(&mp->mnt_secondary_writes);
|
|
MNT_IUNLOCK(mp);
|
|
}
|
|
|
|
/*
|
|
* Request a filesystem to suspend write operations.
|
|
*/
|
|
int
|
|
vfs_write_suspend(struct mount *mp, int flags)
|
|
{
|
|
int error;
|
|
|
|
vfs_op_enter(mp);
|
|
|
|
MNT_ILOCK(mp);
|
|
vfs_assert_mount_counters(mp);
|
|
if (mp->mnt_susp_owner == curthread) {
|
|
vfs_op_exit_locked(mp);
|
|
MNT_IUNLOCK(mp);
|
|
return (EALREADY);
|
|
}
|
|
while (mp->mnt_kern_flag & MNTK_SUSPEND)
|
|
msleep(&mp->mnt_flag, MNT_MTX(mp), PUSER - 1, "wsuspfs", 0);
|
|
|
|
/*
|
|
* Unmount holds a write reference on the mount point. If we
|
|
* own busy reference and drain for writers, we deadlock with
|
|
* the reference draining in the unmount path. Callers of
|
|
* vfs_write_suspend() must specify VS_SKIP_UNMOUNT if
|
|
* vfs_busy() reference is owned and caller is not in the
|
|
* unmount context.
|
|
*/
|
|
if ((flags & VS_SKIP_UNMOUNT) != 0 &&
|
|
(mp->mnt_kern_flag & MNTK_UNMOUNT) != 0) {
|
|
vfs_op_exit_locked(mp);
|
|
MNT_IUNLOCK(mp);
|
|
return (EBUSY);
|
|
}
|
|
|
|
mp->mnt_kern_flag |= MNTK_SUSPEND;
|
|
mp->mnt_susp_owner = curthread;
|
|
if (mp->mnt_writeopcount > 0)
|
|
(void) msleep(&mp->mnt_writeopcount,
|
|
MNT_MTX(mp), (PUSER - 1)|PDROP, "suspwt", 0);
|
|
else
|
|
MNT_IUNLOCK(mp);
|
|
if ((error = VFS_SYNC(mp, MNT_SUSPEND)) != 0) {
|
|
vfs_write_resume(mp, 0);
|
|
/* vfs_write_resume does vfs_op_exit() for us */
|
|
}
|
|
return (error);
|
|
}
|
|
|
|
/*
|
|
* Request a filesystem to resume write operations.
|
|
*/
|
|
void
|
|
vfs_write_resume(struct mount *mp, int flags)
|
|
{
|
|
|
|
MNT_ILOCK(mp);
|
|
if ((mp->mnt_kern_flag & MNTK_SUSPEND) != 0) {
|
|
KASSERT(mp->mnt_susp_owner == curthread, ("mnt_susp_owner"));
|
|
mp->mnt_kern_flag &= ~(MNTK_SUSPEND | MNTK_SUSPEND2 |
|
|
MNTK_SUSPENDED);
|
|
mp->mnt_susp_owner = NULL;
|
|
wakeup(&mp->mnt_writeopcount);
|
|
wakeup(&mp->mnt_flag);
|
|
curthread->td_pflags &= ~TDP_IGNSUSP;
|
|
if ((flags & VR_START_WRITE) != 0) {
|
|
MNT_REF(mp);
|
|
mp->mnt_writeopcount++;
|
|
}
|
|
MNT_IUNLOCK(mp);
|
|
if ((flags & VR_NO_SUSPCLR) == 0)
|
|
VFS_SUSP_CLEAN(mp);
|
|
vfs_op_exit(mp);
|
|
} else if ((flags & VR_START_WRITE) != 0) {
|
|
MNT_REF(mp);
|
|
vn_start_write_refed(mp, 0, true);
|
|
} else {
|
|
MNT_IUNLOCK(mp);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Helper loop around vfs_write_suspend() for filesystem unmount VFS
|
|
* methods.
|
|
*/
|
|
int
|
|
vfs_write_suspend_umnt(struct mount *mp)
|
|
{
|
|
int error;
|
|
|
|
KASSERT((curthread->td_pflags & TDP_IGNSUSP) == 0,
|
|
("vfs_write_suspend_umnt: recursed"));
|
|
|
|
/* dounmount() already called vn_start_write(). */
|
|
for (;;) {
|
|
vn_finished_write(mp);
|
|
error = vfs_write_suspend(mp, 0);
|
|
if (error != 0) {
|
|
vn_start_write(NULL, &mp, V_WAIT);
|
|
return (error);
|
|
}
|
|
MNT_ILOCK(mp);
|
|
if ((mp->mnt_kern_flag & MNTK_SUSPENDED) != 0)
|
|
break;
|
|
MNT_IUNLOCK(mp);
|
|
vn_start_write(NULL, &mp, V_WAIT);
|
|
}
|
|
mp->mnt_kern_flag &= ~(MNTK_SUSPENDED | MNTK_SUSPEND2);
|
|
wakeup(&mp->mnt_flag);
|
|
MNT_IUNLOCK(mp);
|
|
curthread->td_pflags |= TDP_IGNSUSP;
|
|
return (0);
|
|
}
|
|
|
|
/*
|
|
* Implement kqueues for files by translating it to vnode operation.
|
|
*/
|
|
static int
|
|
vn_kqfilter(struct file *fp, struct knote *kn)
|
|
{
|
|
|
|
return (VOP_KQFILTER(fp->f_vnode, kn));
|
|
}
|
|
|
|
/*
|
|
* Simplified in-kernel wrapper calls for extended attribute access.
|
|
* Both calls pass in a NULL credential, authorizing as "kernel" access.
|
|
* Set IO_NODELOCKED in ioflg if the vnode is already locked.
|
|
*/
|
|
int
|
|
vn_extattr_get(struct vnode *vp, int ioflg, int attrnamespace,
|
|
const char *attrname, int *buflen, char *buf, struct thread *td)
|
|
{
|
|
struct uio auio;
|
|
struct iovec iov;
|
|
int error;
|
|
|
|
iov.iov_len = *buflen;
|
|
iov.iov_base = buf;
|
|
|
|
auio.uio_iov = &iov;
|
|
auio.uio_iovcnt = 1;
|
|
auio.uio_rw = UIO_READ;
|
|
auio.uio_segflg = UIO_SYSSPACE;
|
|
auio.uio_td = td;
|
|
auio.uio_offset = 0;
|
|
auio.uio_resid = *buflen;
|
|
|
|
if ((ioflg & IO_NODELOCKED) == 0)
|
|
vn_lock(vp, LK_SHARED | LK_RETRY);
|
|
|
|
ASSERT_VOP_LOCKED(vp, "IO_NODELOCKED with no vp lock held");
|
|
|
|
/* authorize attribute retrieval as kernel */
|
|
error = VOP_GETEXTATTR(vp, attrnamespace, attrname, &auio, NULL, NULL,
|
|
td);
|
|
|
|
if ((ioflg & IO_NODELOCKED) == 0)
|
|
VOP_UNLOCK(vp);
|
|
|
|
if (error == 0) {
|
|
*buflen = *buflen - auio.uio_resid;
|
|
}
|
|
|
|
return (error);
|
|
}
|
|
|
|
/*
|
|
* XXX failure mode if partially written?
|
|
*/
|
|
int
|
|
vn_extattr_set(struct vnode *vp, int ioflg, int attrnamespace,
|
|
const char *attrname, int buflen, char *buf, struct thread *td)
|
|
{
|
|
struct uio auio;
|
|
struct iovec iov;
|
|
struct mount *mp;
|
|
int error;
|
|
|
|
iov.iov_len = buflen;
|
|
iov.iov_base = buf;
|
|
|
|
auio.uio_iov = &iov;
|
|
auio.uio_iovcnt = 1;
|
|
auio.uio_rw = UIO_WRITE;
|
|
auio.uio_segflg = UIO_SYSSPACE;
|
|
auio.uio_td = td;
|
|
auio.uio_offset = 0;
|
|
auio.uio_resid = buflen;
|
|
|
|
if ((ioflg & IO_NODELOCKED) == 0) {
|
|
if ((error = vn_start_write(vp, &mp, V_WAIT)) != 0)
|
|
return (error);
|
|
vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
|
|
}
|
|
|
|
ASSERT_VOP_LOCKED(vp, "IO_NODELOCKED with no vp lock held");
|
|
|
|
/* authorize attribute setting as kernel */
|
|
error = VOP_SETEXTATTR(vp, attrnamespace, attrname, &auio, NULL, td);
|
|
|
|
if ((ioflg & IO_NODELOCKED) == 0) {
|
|
vn_finished_write(mp);
|
|
VOP_UNLOCK(vp);
|
|
}
|
|
|
|
return (error);
|
|
}
|
|
|
|
int
|
|
vn_extattr_rm(struct vnode *vp, int ioflg, int attrnamespace,
|
|
const char *attrname, struct thread *td)
|
|
{
|
|
struct mount *mp;
|
|
int error;
|
|
|
|
if ((ioflg & IO_NODELOCKED) == 0) {
|
|
if ((error = vn_start_write(vp, &mp, V_WAIT)) != 0)
|
|
return (error);
|
|
vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
|
|
}
|
|
|
|
ASSERT_VOP_LOCKED(vp, "IO_NODELOCKED with no vp lock held");
|
|
|
|
/* authorize attribute removal as kernel */
|
|
error = VOP_DELETEEXTATTR(vp, attrnamespace, attrname, NULL, td);
|
|
if (error == EOPNOTSUPP)
|
|
error = VOP_SETEXTATTR(vp, attrnamespace, attrname, NULL,
|
|
NULL, td);
|
|
|
|
if ((ioflg & IO_NODELOCKED) == 0) {
|
|
vn_finished_write(mp);
|
|
VOP_UNLOCK(vp);
|
|
}
|
|
|
|
return (error);
|
|
}
|
|
|
|
static int
|
|
vn_get_ino_alloc_vget(struct mount *mp, void *arg, int lkflags,
|
|
struct vnode **rvp)
|
|
{
|
|
|
|
return (VFS_VGET(mp, *(ino_t *)arg, lkflags, rvp));
|
|
}
|
|
|
|
int
|
|
vn_vget_ino(struct vnode *vp, ino_t ino, int lkflags, struct vnode **rvp)
|
|
{
|
|
|
|
return (vn_vget_ino_gen(vp, vn_get_ino_alloc_vget, &ino,
|
|
lkflags, rvp));
|
|
}
|
|
|
|
int
|
|
vn_vget_ino_gen(struct vnode *vp, vn_get_ino_t alloc, void *alloc_arg,
|
|
int lkflags, struct vnode **rvp)
|
|
{
|
|
struct mount *mp;
|
|
int ltype, error;
|
|
|
|
ASSERT_VOP_LOCKED(vp, "vn_vget_ino_get");
|
|
mp = vp->v_mount;
|
|
ltype = VOP_ISLOCKED(vp);
|
|
KASSERT(ltype == LK_EXCLUSIVE || ltype == LK_SHARED,
|
|
("vn_vget_ino: vp not locked"));
|
|
error = vfs_busy(mp, MBF_NOWAIT);
|
|
if (error != 0) {
|
|
vfs_ref(mp);
|
|
VOP_UNLOCK(vp);
|
|
error = vfs_busy(mp, 0);
|
|
vn_lock(vp, ltype | LK_RETRY);
|
|
vfs_rel(mp);
|
|
if (error != 0)
|
|
return (ENOENT);
|
|
if (VN_IS_DOOMED(vp)) {
|
|
vfs_unbusy(mp);
|
|
return (ENOENT);
|
|
}
|
|
}
|
|
VOP_UNLOCK(vp);
|
|
error = alloc(mp, alloc_arg, lkflags, rvp);
|
|
vfs_unbusy(mp);
|
|
if (error != 0 || *rvp != vp)
|
|
vn_lock(vp, ltype | LK_RETRY);
|
|
if (VN_IS_DOOMED(vp)) {
|
|
if (error == 0) {
|
|
if (*rvp == vp)
|
|
vunref(vp);
|
|
else
|
|
vput(*rvp);
|
|
}
|
|
error = ENOENT;
|
|
}
|
|
return (error);
|
|
}
|
|
|
|
int
|
|
vn_rlimit_fsize(const struct vnode *vp, const struct uio *uio,
|
|
struct thread *td)
|
|
{
|
|
|
|
if (vp->v_type != VREG || td == NULL)
|
|
return (0);
|
|
if ((uoff_t)uio->uio_offset + uio->uio_resid >
|
|
lim_cur(td, RLIMIT_FSIZE)) {
|
|
PROC_LOCK(td->td_proc);
|
|
kern_psignal(td->td_proc, SIGXFSZ);
|
|
PROC_UNLOCK(td->td_proc);
|
|
return (EFBIG);
|
|
}
|
|
return (0);
|
|
}
|
|
|
|
int
|
|
vn_chmod(struct file *fp, mode_t mode, struct ucred *active_cred,
|
|
struct thread *td)
|
|
{
|
|
struct vnode *vp;
|
|
|
|
vp = fp->f_vnode;
|
|
#ifdef AUDIT
|
|
vn_lock(vp, LK_SHARED | LK_RETRY);
|
|
AUDIT_ARG_VNODE1(vp);
|
|
VOP_UNLOCK(vp);
|
|
#endif
|
|
return (setfmode(td, active_cred, vp, mode));
|
|
}
|
|
|
|
int
|
|
vn_chown(struct file *fp, uid_t uid, gid_t gid, struct ucred *active_cred,
|
|
struct thread *td)
|
|
{
|
|
struct vnode *vp;
|
|
|
|
vp = fp->f_vnode;
|
|
#ifdef AUDIT
|
|
vn_lock(vp, LK_SHARED | LK_RETRY);
|
|
AUDIT_ARG_VNODE1(vp);
|
|
VOP_UNLOCK(vp);
|
|
#endif
|
|
return (setfown(td, active_cred, vp, uid, gid));
|
|
}
|
|
|
|
void
|
|
vn_pages_remove(struct vnode *vp, vm_pindex_t start, vm_pindex_t end)
|
|
{
|
|
vm_object_t object;
|
|
|
|
if ((object = vp->v_object) == NULL)
|
|
return;
|
|
VM_OBJECT_WLOCK(object);
|
|
vm_object_page_remove(object, start, end, 0);
|
|
VM_OBJECT_WUNLOCK(object);
|
|
}
|
|
|
|
int
|
|
vn_bmap_seekhole(struct vnode *vp, u_long cmd, off_t *off, struct ucred *cred)
|
|
{
|
|
struct vattr va;
|
|
daddr_t bn, bnp;
|
|
uint64_t bsize;
|
|
off_t noff;
|
|
int error;
|
|
|
|
KASSERT(cmd == FIOSEEKHOLE || cmd == FIOSEEKDATA,
|
|
("Wrong command %lu", cmd));
|
|
|
|
if (vn_lock(vp, LK_SHARED) != 0)
|
|
return (EBADF);
|
|
if (vp->v_type != VREG) {
|
|
error = ENOTTY;
|
|
goto unlock;
|
|
}
|
|
error = VOP_GETATTR(vp, &va, cred);
|
|
if (error != 0)
|
|
goto unlock;
|
|
noff = *off;
|
|
if (noff >= va.va_size) {
|
|
error = ENXIO;
|
|
goto unlock;
|
|
}
|
|
bsize = vp->v_mount->mnt_stat.f_iosize;
|
|
for (bn = noff / bsize; noff < va.va_size; bn++, noff += bsize -
|
|
noff % bsize) {
|
|
error = VOP_BMAP(vp, bn, NULL, &bnp, NULL, NULL);
|
|
if (error == EOPNOTSUPP) {
|
|
error = ENOTTY;
|
|
goto unlock;
|
|
}
|
|
if ((bnp == -1 && cmd == FIOSEEKHOLE) ||
|
|
(bnp != -1 && cmd == FIOSEEKDATA)) {
|
|
noff = bn * bsize;
|
|
if (noff < *off)
|
|
noff = *off;
|
|
goto unlock;
|
|
}
|
|
}
|
|
if (noff > va.va_size)
|
|
noff = va.va_size;
|
|
/* noff == va.va_size. There is an implicit hole at the end of file. */
|
|
if (cmd == FIOSEEKDATA)
|
|
error = ENXIO;
|
|
unlock:
|
|
VOP_UNLOCK(vp);
|
|
if (error == 0)
|
|
*off = noff;
|
|
return (error);
|
|
}
|
|
|
|
int
|
|
vn_seek(struct file *fp, off_t offset, int whence, struct thread *td)
|
|
{
|
|
struct ucred *cred;
|
|
struct vnode *vp;
|
|
struct vattr vattr;
|
|
off_t foffset, size;
|
|
int error, noneg;
|
|
|
|
cred = td->td_ucred;
|
|
vp = fp->f_vnode;
|
|
foffset = foffset_lock(fp, 0);
|
|
noneg = (vp->v_type != VCHR);
|
|
error = 0;
|
|
switch (whence) {
|
|
case L_INCR:
|
|
if (noneg &&
|
|
(foffset < 0 ||
|
|
(offset > 0 && foffset > OFF_MAX - offset))) {
|
|
error = EOVERFLOW;
|
|
break;
|
|
}
|
|
offset += foffset;
|
|
break;
|
|
case L_XTND:
|
|
vn_lock(vp, LK_SHARED | LK_RETRY);
|
|
error = VOP_GETATTR(vp, &vattr, cred);
|
|
VOP_UNLOCK(vp);
|
|
if (error)
|
|
break;
|
|
|
|
/*
|
|
* If the file references a disk device, then fetch
|
|
* the media size and use that to determine the ending
|
|
* offset.
|
|
*/
|
|
if (vattr.va_size == 0 && vp->v_type == VCHR &&
|
|
fo_ioctl(fp, DIOCGMEDIASIZE, &size, cred, td) == 0)
|
|
vattr.va_size = size;
|
|
if (noneg &&
|
|
(vattr.va_size > OFF_MAX ||
|
|
(offset > 0 && vattr.va_size > OFF_MAX - offset))) {
|
|
error = EOVERFLOW;
|
|
break;
|
|
}
|
|
offset += vattr.va_size;
|
|
break;
|
|
case L_SET:
|
|
break;
|
|
case SEEK_DATA:
|
|
error = fo_ioctl(fp, FIOSEEKDATA, &offset, cred, td);
|
|
if (error == ENOTTY)
|
|
error = EINVAL;
|
|
break;
|
|
case SEEK_HOLE:
|
|
error = fo_ioctl(fp, FIOSEEKHOLE, &offset, cred, td);
|
|
if (error == ENOTTY)
|
|
error = EINVAL;
|
|
break;
|
|
default:
|
|
error = EINVAL;
|
|
}
|
|
if (error == 0 && noneg && offset < 0)
|
|
error = EINVAL;
|
|
if (error != 0)
|
|
goto drop;
|
|
VFS_KNOTE_UNLOCKED(vp, 0);
|
|
td->td_uretoff.tdu_off = offset;
|
|
drop:
|
|
foffset_unlock(fp, offset, error != 0 ? FOF_NOUPDATE : 0);
|
|
return (error);
|
|
}
|
|
|
|
int
|
|
vn_utimes_perm(struct vnode *vp, struct vattr *vap, struct ucred *cred,
|
|
struct thread *td)
|
|
{
|
|
int error;
|
|
|
|
/*
|
|
* Grant permission if the caller is the owner of the file, or
|
|
* the super-user, or has ACL_WRITE_ATTRIBUTES permission on
|
|
* on the file. If the time pointer is null, then write
|
|
* permission on the file is also sufficient.
|
|
*
|
|
* From NFSv4.1, draft 21, 6.2.1.3.1, Discussion of Mask Attributes:
|
|
* A user having ACL_WRITE_DATA or ACL_WRITE_ATTRIBUTES
|
|
* will be allowed to set the times [..] to the current
|
|
* server time.
|
|
*/
|
|
error = VOP_ACCESSX(vp, VWRITE_ATTRIBUTES, cred, td);
|
|
if (error != 0 && (vap->va_vaflags & VA_UTIMES_NULL) != 0)
|
|
error = VOP_ACCESS(vp, VWRITE, cred, td);
|
|
return (error);
|
|
}
|
|
|
|
int
|
|
vn_fill_kinfo(struct file *fp, struct kinfo_file *kif, struct filedesc *fdp)
|
|
{
|
|
struct vnode *vp;
|
|
int error;
|
|
|
|
if (fp->f_type == DTYPE_FIFO)
|
|
kif->kf_type = KF_TYPE_FIFO;
|
|
else
|
|
kif->kf_type = KF_TYPE_VNODE;
|
|
vp = fp->f_vnode;
|
|
vref(vp);
|
|
FILEDESC_SUNLOCK(fdp);
|
|
error = vn_fill_kinfo_vnode(vp, kif);
|
|
vrele(vp);
|
|
FILEDESC_SLOCK(fdp);
|
|
return (error);
|
|
}
|
|
|
|
static inline void
|
|
vn_fill_junk(struct kinfo_file *kif)
|
|
{
|
|
size_t len, olen;
|
|
|
|
/*
|
|
* Simulate vn_fullpath returning changing values for a given
|
|
* vp during e.g. coredump.
|
|
*/
|
|
len = (arc4random() % (sizeof(kif->kf_path) - 2)) + 1;
|
|
olen = strlen(kif->kf_path);
|
|
if (len < olen)
|
|
strcpy(&kif->kf_path[len - 1], "$");
|
|
else
|
|
for (; olen < len; olen++)
|
|
strcpy(&kif->kf_path[olen], "A");
|
|
}
|
|
|
|
int
|
|
vn_fill_kinfo_vnode(struct vnode *vp, struct kinfo_file *kif)
|
|
{
|
|
struct vattr va;
|
|
char *fullpath, *freepath;
|
|
int error;
|
|
|
|
kif->kf_un.kf_file.kf_file_type = vntype_to_kinfo(vp->v_type);
|
|
freepath = NULL;
|
|
fullpath = "-";
|
|
error = vn_fullpath(curthread, vp, &fullpath, &freepath);
|
|
if (error == 0) {
|
|
strlcpy(kif->kf_path, fullpath, sizeof(kif->kf_path));
|
|
}
|
|
if (freepath != NULL)
|
|
free(freepath, M_TEMP);
|
|
|
|
KFAIL_POINT_CODE(DEBUG_FP, fill_kinfo_vnode__random_path,
|
|
vn_fill_junk(kif);
|
|
);
|
|
|
|
/*
|
|
* Retrieve vnode attributes.
|
|
*/
|
|
va.va_fsid = VNOVAL;
|
|
va.va_rdev = NODEV;
|
|
vn_lock(vp, LK_SHARED | LK_RETRY);
|
|
error = VOP_GETATTR(vp, &va, curthread->td_ucred);
|
|
VOP_UNLOCK(vp);
|
|
if (error != 0)
|
|
return (error);
|
|
if (va.va_fsid != VNOVAL)
|
|
kif->kf_un.kf_file.kf_file_fsid = va.va_fsid;
|
|
else
|
|
kif->kf_un.kf_file.kf_file_fsid =
|
|
vp->v_mount->mnt_stat.f_fsid.val[0];
|
|
kif->kf_un.kf_file.kf_file_fsid_freebsd11 =
|
|
kif->kf_un.kf_file.kf_file_fsid; /* truncate */
|
|
kif->kf_un.kf_file.kf_file_fileid = va.va_fileid;
|
|
kif->kf_un.kf_file.kf_file_mode = MAKEIMODE(va.va_type, va.va_mode);
|
|
kif->kf_un.kf_file.kf_file_size = va.va_size;
|
|
kif->kf_un.kf_file.kf_file_rdev = va.va_rdev;
|
|
kif->kf_un.kf_file.kf_file_rdev_freebsd11 =
|
|
kif->kf_un.kf_file.kf_file_rdev; /* truncate */
|
|
return (0);
|
|
}
|
|
|
|
int
|
|
vn_mmap(struct file *fp, vm_map_t map, vm_offset_t *addr, vm_size_t size,
|
|
vm_prot_t prot, vm_prot_t cap_maxprot, int flags, vm_ooffset_t foff,
|
|
struct thread *td)
|
|
{
|
|
#ifdef HWPMC_HOOKS
|
|
struct pmckern_map_in pkm;
|
|
#endif
|
|
struct mount *mp;
|
|
struct vnode *vp;
|
|
vm_object_t object;
|
|
vm_prot_t maxprot;
|
|
boolean_t writecounted;
|
|
int error;
|
|
|
|
#if defined(COMPAT_FREEBSD7) || defined(COMPAT_FREEBSD6) || \
|
|
defined(COMPAT_FREEBSD5) || defined(COMPAT_FREEBSD4)
|
|
/*
|
|
* POSIX shared-memory objects are defined to have
|
|
* kernel persistence, and are not defined to support
|
|
* read(2)/write(2) -- or even open(2). Thus, we can
|
|
* use MAP_ASYNC to trade on-disk coherence for speed.
|
|
* The shm_open(3) library routine turns on the FPOSIXSHM
|
|
* flag to request this behavior.
|
|
*/
|
|
if ((fp->f_flag & FPOSIXSHM) != 0)
|
|
flags |= MAP_NOSYNC;
|
|
#endif
|
|
vp = fp->f_vnode;
|
|
|
|
/*
|
|
* 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?
|
|
*/
|
|
mp = vp->v_mount;
|
|
if (mp != NULL && (mp->mnt_flag & MNT_NOEXEC) != 0) {
|
|
maxprot = VM_PROT_NONE;
|
|
if ((prot & VM_PROT_EXECUTE) != 0)
|
|
return (EACCES);
|
|
} else
|
|
maxprot = VM_PROT_EXECUTE;
|
|
if ((fp->f_flag & FREAD) != 0)
|
|
maxprot |= VM_PROT_READ;
|
|
else if ((prot & VM_PROT_READ) != 0)
|
|
return (EACCES);
|
|
|
|
/*
|
|
* If we are sharing potential changes via MAP_SHARED and we
|
|
* are trying to get write permission although we opened it
|
|
* without asking for it, bail out.
|
|
*/
|
|
if ((flags & MAP_SHARED) != 0) {
|
|
if ((fp->f_flag & FWRITE) != 0)
|
|
maxprot |= VM_PROT_WRITE;
|
|
else if ((prot & VM_PROT_WRITE) != 0)
|
|
return (EACCES);
|
|
} else {
|
|
maxprot |= VM_PROT_WRITE;
|
|
cap_maxprot |= VM_PROT_WRITE;
|
|
}
|
|
maxprot &= cap_maxprot;
|
|
|
|
/*
|
|
* For regular files and shared memory, POSIX requires that
|
|
* the value of foff be a legitimate offset within the data
|
|
* object. In particular, negative offsets are invalid.
|
|
* Blocking negative offsets and overflows here avoids
|
|
* possible wraparound or user-level access into reserved
|
|
* ranges of the data object later. In contrast, POSIX does
|
|
* not dictate how offsets are used by device drivers, so in
|
|
* the case of a device mapping a negative offset is passed
|
|
* on.
|
|
*/
|
|
if (
|
|
#ifdef _LP64
|
|
size > OFF_MAX ||
|
|
#endif
|
|
foff < 0 || foff > OFF_MAX - size)
|
|
return (EINVAL);
|
|
|
|
writecounted = FALSE;
|
|
error = vm_mmap_vnode(td, size, prot, &maxprot, &flags, vp,
|
|
&foff, &object, &writecounted);
|
|
if (error != 0)
|
|
return (error);
|
|
error = vm_mmap_object(map, addr, size, prot, maxprot, flags, object,
|
|
foff, writecounted, td);
|
|
if (error != 0) {
|
|
/*
|
|
* If this mapping was accounted for in the vnode's
|
|
* writecount, then undo that now.
|
|
*/
|
|
if (writecounted)
|
|
vm_pager_release_writecount(object, 0, size);
|
|
vm_object_deallocate(object);
|
|
}
|
|
#ifdef HWPMC_HOOKS
|
|
/* Inform hwpmc(4) if an executable is being mapped. */
|
|
if (PMC_HOOK_INSTALLED(PMC_FN_MMAP)) {
|
|
if ((prot & VM_PROT_EXECUTE) != 0 && error == 0) {
|
|
pkm.pm_file = vp;
|
|
pkm.pm_address = (uintptr_t) *addr;
|
|
PMC_CALL_HOOK_UNLOCKED(td, PMC_FN_MMAP, (void *) &pkm);
|
|
}
|
|
}
|
|
#endif
|
|
return (error);
|
|
}
|
|
|
|
void
|
|
vn_fsid(struct vnode *vp, struct vattr *va)
|
|
{
|
|
fsid_t *f;
|
|
|
|
f = &vp->v_mount->mnt_stat.f_fsid;
|
|
va->va_fsid = (uint32_t)f->val[1];
|
|
va->va_fsid <<= sizeof(f->val[1]) * NBBY;
|
|
va->va_fsid += (uint32_t)f->val[0];
|
|
}
|
|
|
|
int
|
|
vn_fsync_buf(struct vnode *vp, int waitfor)
|
|
{
|
|
struct buf *bp, *nbp;
|
|
struct bufobj *bo;
|
|
struct mount *mp;
|
|
int error, maxretry;
|
|
|
|
error = 0;
|
|
maxretry = 10000; /* large, arbitrarily chosen */
|
|
mp = NULL;
|
|
if (vp->v_type == VCHR) {
|
|
VI_LOCK(vp);
|
|
mp = vp->v_rdev->si_mountpt;
|
|
VI_UNLOCK(vp);
|
|
}
|
|
bo = &vp->v_bufobj;
|
|
BO_LOCK(bo);
|
|
loop1:
|
|
/*
|
|
* MARK/SCAN initialization to avoid infinite loops.
|
|
*/
|
|
TAILQ_FOREACH(bp, &bo->bo_dirty.bv_hd, b_bobufs) {
|
|
bp->b_vflags &= ~BV_SCANNED;
|
|
bp->b_error = 0;
|
|
}
|
|
|
|
/*
|
|
* Flush all dirty buffers associated with a vnode.
|
|
*/
|
|
loop2:
|
|
TAILQ_FOREACH_SAFE(bp, &bo->bo_dirty.bv_hd, b_bobufs, nbp) {
|
|
if ((bp->b_vflags & BV_SCANNED) != 0)
|
|
continue;
|
|
bp->b_vflags |= BV_SCANNED;
|
|
if (BUF_LOCK(bp, LK_EXCLUSIVE | LK_NOWAIT, NULL)) {
|
|
if (waitfor != MNT_WAIT)
|
|
continue;
|
|
if (BUF_LOCK(bp,
|
|
LK_EXCLUSIVE | LK_INTERLOCK | LK_SLEEPFAIL,
|
|
BO_LOCKPTR(bo)) != 0) {
|
|
BO_LOCK(bo);
|
|
goto loop1;
|
|
}
|
|
BO_LOCK(bo);
|
|
}
|
|
BO_UNLOCK(bo);
|
|
KASSERT(bp->b_bufobj == bo,
|
|
("bp %p wrong b_bufobj %p should be %p",
|
|
bp, bp->b_bufobj, bo));
|
|
if ((bp->b_flags & B_DELWRI) == 0)
|
|
panic("fsync: not dirty");
|
|
if ((vp->v_object != NULL) && (bp->b_flags & B_CLUSTEROK)) {
|
|
vfs_bio_awrite(bp);
|
|
} else {
|
|
bremfree(bp);
|
|
bawrite(bp);
|
|
}
|
|
if (maxretry < 1000)
|
|
pause("dirty", hz < 1000 ? 1 : hz / 1000);
|
|
BO_LOCK(bo);
|
|
goto loop2;
|
|
}
|
|
|
|
/*
|
|
* If synchronous the caller expects us to completely resolve all
|
|
* dirty buffers in the system. Wait for in-progress I/O to
|
|
* complete (which could include background bitmap writes), then
|
|
* retry if dirty blocks still exist.
|
|
*/
|
|
if (waitfor == MNT_WAIT) {
|
|
bufobj_wwait(bo, 0, 0);
|
|
if (bo->bo_dirty.bv_cnt > 0) {
|
|
/*
|
|
* If we are unable to write any of these buffers
|
|
* then we fail now rather than trying endlessly
|
|
* to write them out.
|
|
*/
|
|
TAILQ_FOREACH(bp, &bo->bo_dirty.bv_hd, b_bobufs)
|
|
if ((error = bp->b_error) != 0)
|
|
break;
|
|
if ((mp != NULL && mp->mnt_secondary_writes > 0) ||
|
|
(error == 0 && --maxretry >= 0))
|
|
goto loop1;
|
|
if (error == 0)
|
|
error = EAGAIN;
|
|
}
|
|
}
|
|
BO_UNLOCK(bo);
|
|
if (error != 0)
|
|
vn_printf(vp, "fsync: giving up on dirty (error = %d) ", error);
|
|
|
|
return (error);
|
|
}
|
|
|
|
/*
|
|
* Copies a byte range from invp to outvp. Calls VOP_COPY_FILE_RANGE()
|
|
* or vn_generic_copy_file_range() after rangelocking the byte ranges,
|
|
* to do the actual copy.
|
|
* vn_generic_copy_file_range() is factored out, so it can be called
|
|
* from a VOP_COPY_FILE_RANGE() call as well, but handles vnodes from
|
|
* different file systems.
|
|
*/
|
|
int
|
|
vn_copy_file_range(struct vnode *invp, off_t *inoffp, struct vnode *outvp,
|
|
off_t *outoffp, size_t *lenp, unsigned int flags, struct ucred *incred,
|
|
struct ucred *outcred, struct thread *fsize_td)
|
|
{
|
|
int error;
|
|
size_t len;
|
|
uint64_t uvalin, uvalout;
|
|
|
|
len = *lenp;
|
|
*lenp = 0; /* For error returns. */
|
|
error = 0;
|
|
|
|
/* Do some sanity checks on the arguments. */
|
|
uvalin = *inoffp;
|
|
uvalin += len;
|
|
uvalout = *outoffp;
|
|
uvalout += len;
|
|
if (invp->v_type == VDIR || outvp->v_type == VDIR)
|
|
error = EISDIR;
|
|
else if (*inoffp < 0 || uvalin > INT64_MAX || uvalin <
|
|
(uint64_t)*inoffp || *outoffp < 0 || uvalout > INT64_MAX ||
|
|
uvalout < (uint64_t)*outoffp || invp->v_type != VREG ||
|
|
outvp->v_type != VREG)
|
|
error = EINVAL;
|
|
if (error != 0)
|
|
goto out;
|
|
|
|
/*
|
|
* If the two vnode are for the same file system, call
|
|
* VOP_COPY_FILE_RANGE(), otherwise call vn_generic_copy_file_range()
|
|
* which can handle copies across multiple file systems.
|
|
*/
|
|
*lenp = len;
|
|
if (invp->v_mount == outvp->v_mount)
|
|
error = VOP_COPY_FILE_RANGE(invp, inoffp, outvp, outoffp,
|
|
lenp, flags, incred, outcred, fsize_td);
|
|
else
|
|
error = vn_generic_copy_file_range(invp, inoffp, outvp,
|
|
outoffp, lenp, flags, incred, outcred, fsize_td);
|
|
out:
|
|
return (error);
|
|
}
|
|
|
|
/*
|
|
* Test len bytes of data starting at dat for all bytes == 0.
|
|
* Return true if all bytes are zero, false otherwise.
|
|
* Expects dat to be well aligned.
|
|
*/
|
|
static bool
|
|
mem_iszero(void *dat, int len)
|
|
{
|
|
int i;
|
|
const u_int *p;
|
|
const char *cp;
|
|
|
|
for (p = dat; len > 0; len -= sizeof(*p), p++) {
|
|
if (len >= sizeof(*p)) {
|
|
if (*p != 0)
|
|
return (false);
|
|
} else {
|
|
cp = (const char *)p;
|
|
for (i = 0; i < len; i++, cp++)
|
|
if (*cp != '\0')
|
|
return (false);
|
|
}
|
|
}
|
|
return (true);
|
|
}
|
|
|
|
/*
|
|
* Look for a hole in the output file and, if found, adjust *outoffp
|
|
* and *xferp to skip past the hole.
|
|
* *xferp is the entire hole length to be written and xfer2 is how many bytes
|
|
* to be written as 0's upon return.
|
|
*/
|
|
static off_t
|
|
vn_skip_hole(struct vnode *outvp, off_t xfer2, off_t *outoffp, off_t *xferp,
|
|
off_t *dataoffp, off_t *holeoffp, struct ucred *cred)
|
|
{
|
|
int error;
|
|
off_t delta;
|
|
|
|
if (*holeoffp == 0 || *holeoffp <= *outoffp) {
|
|
*dataoffp = *outoffp;
|
|
error = VOP_IOCTL(outvp, FIOSEEKDATA, dataoffp, 0, cred,
|
|
curthread);
|
|
if (error == 0) {
|
|
*holeoffp = *dataoffp;
|
|
error = VOP_IOCTL(outvp, FIOSEEKHOLE, holeoffp, 0, cred,
|
|
curthread);
|
|
}
|
|
if (error != 0 || *holeoffp == *dataoffp) {
|
|
/*
|
|
* Since outvp is unlocked, it may be possible for
|
|
* another thread to do a truncate(), lseek(), write()
|
|
* creating a hole at startoff between the above
|
|
* VOP_IOCTL() calls, if the other thread does not do
|
|
* rangelocking.
|
|
* If that happens, *holeoffp == *dataoffp and finding
|
|
* the hole has failed, so disable vn_skip_hole().
|
|
*/
|
|
*holeoffp = -1; /* Disable use of vn_skip_hole(). */
|
|
return (xfer2);
|
|
}
|
|
KASSERT(*dataoffp >= *outoffp,
|
|
("vn_skip_hole: dataoff=%jd < outoff=%jd",
|
|
(intmax_t)*dataoffp, (intmax_t)*outoffp));
|
|
KASSERT(*holeoffp > *dataoffp,
|
|
("vn_skip_hole: holeoff=%jd <= dataoff=%jd",
|
|
(intmax_t)*holeoffp, (intmax_t)*dataoffp));
|
|
}
|
|
|
|
/*
|
|
* If there is a hole before the data starts, advance *outoffp and
|
|
* *xferp past the hole.
|
|
*/
|
|
if (*dataoffp > *outoffp) {
|
|
delta = *dataoffp - *outoffp;
|
|
if (delta >= *xferp) {
|
|
/* Entire *xferp is a hole. */
|
|
*outoffp += *xferp;
|
|
*xferp = 0;
|
|
return (0);
|
|
}
|
|
*xferp -= delta;
|
|
*outoffp += delta;
|
|
xfer2 = MIN(xfer2, *xferp);
|
|
}
|
|
|
|
/*
|
|
* If a hole starts before the end of this xfer2, reduce this xfer2 so
|
|
* that the write ends at the start of the hole.
|
|
* *holeoffp should always be greater than *outoffp, but for the
|
|
* non-INVARIANTS case, check this to make sure xfer2 remains a sane
|
|
* value.
|
|
*/
|
|
if (*holeoffp > *outoffp && *holeoffp < *outoffp + xfer2)
|
|
xfer2 = *holeoffp - *outoffp;
|
|
return (xfer2);
|
|
}
|
|
|
|
/*
|
|
* Write an xfer sized chunk to outvp in blksize blocks from dat.
|
|
* dat is a maximum of blksize in length and can be written repeatedly in
|
|
* the chunk.
|
|
* If growfile == true, just grow the file via vn_truncate_locked() instead
|
|
* of doing actual writes.
|
|
* If checkhole == true, a hole is being punched, so skip over any hole
|
|
* already in the output file.
|
|
*/
|
|
static int
|
|
vn_write_outvp(struct vnode *outvp, char *dat, off_t outoff, off_t xfer,
|
|
u_long blksize, bool growfile, bool checkhole, struct ucred *cred)
|
|
{
|
|
struct mount *mp;
|
|
off_t dataoff, holeoff, xfer2;
|
|
int error, lckf;
|
|
|
|
/*
|
|
* Loop around doing writes of blksize until write has been completed.
|
|
* Lock/unlock on each loop iteration so that a bwillwrite() can be
|
|
* done for each iteration, since the xfer argument can be very
|
|
* large if there is a large hole to punch in the output file.
|
|
*/
|
|
error = 0;
|
|
holeoff = 0;
|
|
do {
|
|
xfer2 = MIN(xfer, blksize);
|
|
if (checkhole) {
|
|
/*
|
|
* Punching a hole. Skip writing if there is
|
|
* already a hole in the output file.
|
|
*/
|
|
xfer2 = vn_skip_hole(outvp, xfer2, &outoff, &xfer,
|
|
&dataoff, &holeoff, cred);
|
|
if (xfer == 0)
|
|
break;
|
|
if (holeoff < 0)
|
|
checkhole = false;
|
|
KASSERT(xfer2 > 0, ("vn_write_outvp: xfer2=%jd",
|
|
(intmax_t)xfer2));
|
|
}
|
|
bwillwrite();
|
|
mp = NULL;
|
|
error = vn_start_write(outvp, &mp, V_WAIT);
|
|
if (error == 0) {
|
|
if (MNT_SHARED_WRITES(mp))
|
|
lckf = LK_SHARED;
|
|
else
|
|
lckf = LK_EXCLUSIVE;
|
|
error = vn_lock(outvp, lckf);
|
|
}
|
|
if (error == 0) {
|
|
if (growfile)
|
|
error = vn_truncate_locked(outvp, outoff + xfer,
|
|
false, cred);
|
|
else {
|
|
error = vn_rdwr(UIO_WRITE, outvp, dat, xfer2,
|
|
outoff, UIO_SYSSPACE, IO_NODELOCKED,
|
|
curthread->td_ucred, cred, NULL, curthread);
|
|
outoff += xfer2;
|
|
xfer -= xfer2;
|
|
}
|
|
VOP_UNLOCK(outvp);
|
|
}
|
|
if (mp != NULL)
|
|
vn_finished_write(mp);
|
|
} while (!growfile && xfer > 0 && error == 0);
|
|
return (error);
|
|
}
|
|
|
|
/*
|
|
* Copy a byte range of one file to another. This function can handle the
|
|
* case where invp and outvp are on different file systems.
|
|
* It can also be called by a VOP_COPY_FILE_RANGE() to do the work, if there
|
|
* is no better file system specific way to do it.
|
|
*/
|
|
int
|
|
vn_generic_copy_file_range(struct vnode *invp, off_t *inoffp,
|
|
struct vnode *outvp, off_t *outoffp, size_t *lenp, unsigned int flags,
|
|
struct ucred *incred, struct ucred *outcred, struct thread *fsize_td)
|
|
{
|
|
struct vattr va;
|
|
struct mount *mp;
|
|
struct uio io;
|
|
off_t startoff, endoff, xfer, xfer2;
|
|
u_long blksize;
|
|
int error;
|
|
bool cantseek, readzeros, eof, lastblock;
|
|
ssize_t aresid;
|
|
size_t copylen, len, savlen;
|
|
char *dat;
|
|
long holein, holeout;
|
|
|
|
holein = holeout = 0;
|
|
savlen = len = *lenp;
|
|
error = 0;
|
|
dat = NULL;
|
|
|
|
error = vn_lock(invp, LK_SHARED);
|
|
if (error != 0)
|
|
goto out;
|
|
if (VOP_PATHCONF(invp, _PC_MIN_HOLE_SIZE, &holein) != 0)
|
|
holein = 0;
|
|
VOP_UNLOCK(invp);
|
|
|
|
mp = NULL;
|
|
error = vn_start_write(outvp, &mp, V_WAIT);
|
|
if (error == 0)
|
|
error = vn_lock(outvp, LK_EXCLUSIVE);
|
|
if (error == 0) {
|
|
/*
|
|
* If fsize_td != NULL, do a vn_rlimit_fsize() call,
|
|
* now that outvp is locked.
|
|
*/
|
|
if (fsize_td != NULL) {
|
|
io.uio_offset = *outoffp;
|
|
io.uio_resid = len;
|
|
error = vn_rlimit_fsize(outvp, &io, fsize_td);
|
|
if (error != 0)
|
|
error = EFBIG;
|
|
}
|
|
if (VOP_PATHCONF(outvp, _PC_MIN_HOLE_SIZE, &holeout) != 0)
|
|
holeout = 0;
|
|
/*
|
|
* Holes that are past EOF do not need to be written as a block
|
|
* of zero bytes. So, truncate the output file as far as
|
|
* possible and then use va.va_size to decide if writing 0
|
|
* bytes is necessary in the loop below.
|
|
*/
|
|
if (error == 0)
|
|
error = VOP_GETATTR(outvp, &va, outcred);
|
|
if (error == 0 && va.va_size > *outoffp && va.va_size <=
|
|
*outoffp + len) {
|
|
#ifdef MAC
|
|
error = mac_vnode_check_write(curthread->td_ucred,
|
|
outcred, outvp);
|
|
if (error == 0)
|
|
#endif
|
|
error = vn_truncate_locked(outvp, *outoffp,
|
|
false, outcred);
|
|
if (error == 0)
|
|
va.va_size = *outoffp;
|
|
}
|
|
VOP_UNLOCK(outvp);
|
|
}
|
|
if (mp != NULL)
|
|
vn_finished_write(mp);
|
|
if (error != 0)
|
|
goto out;
|
|
|
|
/*
|
|
* Set the blksize to the larger of the hole sizes for invp and outvp.
|
|
* If hole sizes aren't available, set the blksize to the larger
|
|
* f_iosize of invp and outvp.
|
|
* This code expects the hole sizes and f_iosizes to be powers of 2.
|
|
* This value is clipped at 4Kbytes and 1Mbyte.
|
|
*/
|
|
blksize = MAX(holein, holeout);
|
|
if (blksize == 0)
|
|
blksize = MAX(invp->v_mount->mnt_stat.f_iosize,
|
|
outvp->v_mount->mnt_stat.f_iosize);
|
|
if (blksize < 4096)
|
|
blksize = 4096;
|
|
else if (blksize > 1024 * 1024)
|
|
blksize = 1024 * 1024;
|
|
dat = malloc(blksize, M_TEMP, M_WAITOK);
|
|
|
|
/*
|
|
* If VOP_IOCTL(FIOSEEKHOLE) works for invp, use it and FIOSEEKDATA
|
|
* to find holes. Otherwise, just scan the read block for all 0s
|
|
* in the inner loop where the data copying is done.
|
|
* Note that some file systems such as NFSv3, NFSv4.0 and NFSv4.1 may
|
|
* support holes on the server, but do not support FIOSEEKHOLE.
|
|
*/
|
|
eof = false;
|
|
while (len > 0 && error == 0 && !eof) {
|
|
endoff = 0; /* To shut up compilers. */
|
|
cantseek = true;
|
|
startoff = *inoffp;
|
|
copylen = len;
|
|
|
|
/*
|
|
* Find the next data area. If there is just a hole to EOF,
|
|
* FIOSEEKDATA should fail and then we drop down into the
|
|
* inner loop and create the hole on the outvp file.
|
|
* (I do not know if any file system will report a hole to
|
|
* EOF via FIOSEEKHOLE, but I am pretty sure FIOSEEKDATA
|
|
* will fail for those file systems.)
|
|
*
|
|
* For input files that don't support FIOSEEKDATA/FIOSEEKHOLE,
|
|
* the code just falls through to the inner copy loop.
|
|
*/
|
|
error = EINVAL;
|
|
if (holein > 0)
|
|
error = VOP_IOCTL(invp, FIOSEEKDATA, &startoff, 0,
|
|
incred, curthread);
|
|
if (error == 0) {
|
|
endoff = startoff;
|
|
error = VOP_IOCTL(invp, FIOSEEKHOLE, &endoff, 0,
|
|
incred, curthread);
|
|
/*
|
|
* Since invp is unlocked, it may be possible for
|
|
* another thread to do a truncate(), lseek(), write()
|
|
* creating a hole at startoff between the above
|
|
* VOP_IOCTL() calls, if the other thread does not do
|
|
* rangelocking.
|
|
* If that happens, startoff == endoff and finding
|
|
* the hole has failed, so set an error.
|
|
*/
|
|
if (error == 0 && startoff == endoff)
|
|
error = EINVAL; /* Any error. Reset to 0. */
|
|
}
|
|
if (error == 0) {
|
|
if (startoff > *inoffp) {
|
|
/* Found hole before data block. */
|
|
xfer = MIN(startoff - *inoffp, len);
|
|
if (*outoffp < va.va_size) {
|
|
/* Must write 0s to punch hole. */
|
|
xfer2 = MIN(va.va_size - *outoffp,
|
|
xfer);
|
|
memset(dat, 0, MIN(xfer2, blksize));
|
|
error = vn_write_outvp(outvp, dat,
|
|
*outoffp, xfer2, blksize, false,
|
|
holeout > 0, outcred);
|
|
}
|
|
|
|
if (error == 0 && *outoffp + xfer >
|
|
va.va_size && xfer == len)
|
|
/* Grow last block. */
|
|
error = vn_write_outvp(outvp, dat,
|
|
*outoffp, xfer, blksize, true,
|
|
false, outcred);
|
|
if (error == 0) {
|
|
*inoffp += xfer;
|
|
*outoffp += xfer;
|
|
len -= xfer;
|
|
}
|
|
}
|
|
copylen = MIN(len, endoff - startoff);
|
|
cantseek = false;
|
|
} else {
|
|
cantseek = true;
|
|
startoff = *inoffp;
|
|
copylen = len;
|
|
error = 0;
|
|
}
|
|
|
|
xfer = blksize;
|
|
if (cantseek) {
|
|
/*
|
|
* Set first xfer to end at a block boundary, so that
|
|
* holes are more likely detected in the loop below via
|
|
* the for all bytes 0 method.
|
|
*/
|
|
xfer -= (*inoffp % blksize);
|
|
}
|
|
/* Loop copying the data block. */
|
|
while (copylen > 0 && error == 0 && !eof) {
|
|
if (copylen < xfer)
|
|
xfer = copylen;
|
|
error = vn_lock(invp, LK_SHARED);
|
|
if (error != 0)
|
|
goto out;
|
|
error = vn_rdwr(UIO_READ, invp, dat, xfer,
|
|
startoff, UIO_SYSSPACE, IO_NODELOCKED,
|
|
curthread->td_ucred, incred, &aresid,
|
|
curthread);
|
|
VOP_UNLOCK(invp);
|
|
lastblock = false;
|
|
if (error == 0 && aresid > 0) {
|
|
/* Stop the copy at EOF on the input file. */
|
|
xfer -= aresid;
|
|
eof = true;
|
|
lastblock = true;
|
|
}
|
|
if (error == 0) {
|
|
/*
|
|
* Skip the write for holes past the initial EOF
|
|
* of the output file, unless this is the last
|
|
* write of the output file at EOF.
|
|
*/
|
|
readzeros = cantseek ? mem_iszero(dat, xfer) :
|
|
false;
|
|
if (xfer == len)
|
|
lastblock = true;
|
|
if (!cantseek || *outoffp < va.va_size ||
|
|
lastblock || !readzeros)
|
|
error = vn_write_outvp(outvp, dat,
|
|
*outoffp, xfer, blksize,
|
|
readzeros && lastblock &&
|
|
*outoffp >= va.va_size, false,
|
|
outcred);
|
|
if (error == 0) {
|
|
*inoffp += xfer;
|
|
startoff += xfer;
|
|
*outoffp += xfer;
|
|
copylen -= xfer;
|
|
len -= xfer;
|
|
}
|
|
}
|
|
xfer = blksize;
|
|
}
|
|
}
|
|
out:
|
|
*lenp = savlen - len;
|
|
free(dat, M_TEMP);
|
|
return (error);
|
|
}
|
|
|
|
static int
|
|
vn_fallocate(struct file *fp, off_t offset, off_t len, struct thread *td)
|
|
{
|
|
struct mount *mp;
|
|
struct vnode *vp;
|
|
off_t olen, ooffset;
|
|
int error;
|
|
#ifdef AUDIT
|
|
int audited_vnode1 = 0;
|
|
#endif
|
|
|
|
vp = fp->f_vnode;
|
|
if (vp->v_type != VREG)
|
|
return (ENODEV);
|
|
|
|
/* Allocating blocks may take a long time, so iterate. */
|
|
for (;;) {
|
|
olen = len;
|
|
ooffset = offset;
|
|
|
|
bwillwrite();
|
|
mp = NULL;
|
|
error = vn_start_write(vp, &mp, V_WAIT | PCATCH);
|
|
if (error != 0)
|
|
break;
|
|
error = vn_lock(vp, LK_EXCLUSIVE);
|
|
if (error != 0) {
|
|
vn_finished_write(mp);
|
|
break;
|
|
}
|
|
#ifdef AUDIT
|
|
if (!audited_vnode1) {
|
|
AUDIT_ARG_VNODE1(vp);
|
|
audited_vnode1 = 1;
|
|
}
|
|
#endif
|
|
#ifdef MAC
|
|
error = mac_vnode_check_write(td->td_ucred, fp->f_cred, vp);
|
|
if (error == 0)
|
|
#endif
|
|
error = VOP_ALLOCATE(vp, &offset, &len);
|
|
VOP_UNLOCK(vp);
|
|
vn_finished_write(mp);
|
|
|
|
if (olen + ooffset != offset + len) {
|
|
panic("offset + len changed from %jx/%jx to %jx/%jx",
|
|
ooffset, olen, offset, len);
|
|
}
|
|
if (error != 0 || len == 0)
|
|
break;
|
|
KASSERT(olen > len, ("Iteration did not make progress?"));
|
|
maybe_yield();
|
|
}
|
|
|
|
return (error);
|
|
}
|