/
vfs_syscalls.c
4960 lines (4367 loc) · 108 KB
/
vfs_syscalls.c
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/* $NetBSD: vfs_syscalls.c,v 1.553 2021/09/26 21:29:38 thorpej Exp $ */
/*-
* Copyright (c) 2008, 2009, 2019, 2020 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Andrew Doran.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
/*
* Copyright (c) 1989, 1993
* The Regents of the University of California. All rights reserved.
* (c) UNIX System Laboratories, Inc.
* All or some portions of this file are derived from material licensed
* to the University of California by American Telephone and Telegraph
* Co. or Unix System Laboratories, Inc. and are reproduced herein with
* the permission of UNIX System Laboratories, Inc.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* @(#)vfs_syscalls.c 8.42 (Berkeley) 7/31/95
*/
/*
* Virtual File System System Calls
*/
#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: vfs_syscalls.c,v 1.553 2021/09/26 21:29:38 thorpej Exp $");
#ifdef _KERNEL_OPT
#include "opt_fileassoc.h"
#include "veriexec.h"
#endif
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/namei.h>
#include <sys/filedesc.h>
#include <sys/kernel.h>
#include <sys/file.h>
#include <sys/fcntl.h>
#include <sys/stat.h>
#include <sys/vnode.h>
#include <sys/mount.h>
#include <sys/fstrans.h>
#include <sys/proc.h>
#include <sys/uio.h>
#include <sys/kmem.h>
#include <sys/dirent.h>
#include <sys/sysctl.h>
#include <sys/syscallargs.h>
#include <sys/vfs_syscalls.h>
#include <sys/quota.h>
#include <sys/quotactl.h>
#include <sys/ktrace.h>
#ifdef FILEASSOC
#include <sys/fileassoc.h>
#endif /* FILEASSOC */
#include <sys/extattr.h>
#include <sys/verified_exec.h>
#include <sys/kauth.h>
#include <sys/atomic.h>
#include <sys/module.h>
#include <sys/buf.h>
#include <sys/event.h>
#include <sys/compat_stub.h>
#include <miscfs/genfs/genfs.h>
#include <miscfs/specfs/specdev.h>
#include <nfs/rpcv2.h>
#include <nfs/nfsproto.h>
#include <nfs/nfs.h>
#include <nfs/nfs_var.h>
/* XXX this shouldn't be here */
#ifndef OFF_T_MAX
#define OFF_T_MAX __type_max(off_t)
#endif
static int change_flags(struct vnode *, u_long, struct lwp *);
static int change_mode(struct vnode *, int, struct lwp *);
static int change_owner(struct vnode *, uid_t, gid_t, struct lwp *, int);
static int do_sys_openat(lwp_t *, int, const char *, int, int, int *);
static int do_sys_mkdirat(struct lwp *l, int, const char *, mode_t,
enum uio_seg);
static int do_sys_mkfifoat(struct lwp *, int, const char *, mode_t);
static int do_sys_symlinkat(struct lwp *, const char *, int, const char *,
enum uio_seg);
static int do_sys_renameat(struct lwp *l, int, const char *, int, const char *,
enum uio_seg, int);
static int do_sys_readlinkat(struct lwp *, int, const char *, char *,
size_t, register_t *);
static int do_sys_unlinkat(struct lwp *, int, const char *, int, enum uio_seg);
static int fd_nameiat(struct lwp *, int, struct nameidata *);
static int fd_nameiat_simple_user(struct lwp *, int, const char *,
namei_simple_flags_t, struct vnode **);
/*
* This table is used to maintain compatibility with 4.3BSD
* and NetBSD 0.9 mount syscalls - and possibly other systems.
* Note, the order is important!
*
* Do not modify this table. It should only contain filesystems
* supported by NetBSD 0.9 and 4.3BSD.
*/
const char * const mountcompatnames[] = {
NULL, /* 0 = MOUNT_NONE */
MOUNT_FFS, /* 1 = MOUNT_UFS */
MOUNT_NFS, /* 2 */
MOUNT_MFS, /* 3 */
MOUNT_MSDOS, /* 4 */
MOUNT_CD9660, /* 5 = MOUNT_ISOFS */
MOUNT_FDESC, /* 6 */
MOUNT_KERNFS, /* 7 */
NULL, /* 8 = MOUNT_DEVFS */
MOUNT_AFS, /* 9 */
};
const u_int nmountcompatnames = __arraycount(mountcompatnames);
/*
* Filter event method for EVFILT_FS.
*/
static struct klist fs_klist = SLIST_HEAD_INITIALIZER(&fs_klist);
kmutex_t fs_klist_lock;
CTASSERT((NOTE_SUBMIT & VQ_MOUNT) == 0);
CTASSERT((NOTE_SUBMIT & VQ_UNMOUNT) == 0);
static int
filt_fsattach(struct knote *kn)
{
mutex_enter(&fs_klist_lock);
kn->kn_flags |= EV_CLEAR;
SLIST_INSERT_HEAD(&fs_klist, kn, kn_selnext);
mutex_exit(&fs_klist_lock);
return 0;
}
static void
filt_fsdetach(struct knote *kn)
{
mutex_enter(&fs_klist_lock);
SLIST_REMOVE(&fs_klist, kn, knote, kn_selnext);
mutex_exit(&fs_klist_lock);
}
static int
filt_fs(struct knote *kn, long hint)
{
int rv;
if (hint & NOTE_SUBMIT) {
KASSERT(mutex_owned(&fs_klist_lock));
kn->kn_fflags |= hint & ~NOTE_SUBMIT;
} else {
mutex_enter(&fs_klist_lock);
}
rv = (kn->kn_fflags != 0);
if ((hint & NOTE_SUBMIT) == 0) {
mutex_exit(&fs_klist_lock);
}
return rv;
}
/* referenced in kern_event.c */
const struct filterops fs_filtops = {
.f_flags = FILTEROP_MPSAFE,
.f_attach = filt_fsattach,
.f_detach = filt_fsdetach,
.f_event = filt_fs,
};
static int
fd_nameiat(struct lwp *l, int fdat, struct nameidata *ndp)
{
file_t *dfp;
int error;
if (fdat != AT_FDCWD) {
if ((error = fd_getvnode(fdat, &dfp)) != 0)
goto out;
NDAT(ndp, dfp->f_vnode);
}
error = namei(ndp);
if (fdat != AT_FDCWD)
fd_putfile(fdat);
out:
return error;
}
static int
fd_nameiat_simple_user(struct lwp *l, int fdat, const char *path,
namei_simple_flags_t sflags, struct vnode **vp_ret)
{
file_t *dfp;
struct vnode *dvp;
int error;
if (fdat != AT_FDCWD) {
if ((error = fd_getvnode(fdat, &dfp)) != 0)
goto out;
dvp = dfp->f_vnode;
} else {
dvp = NULL;
}
error = nameiat_simple_user(dvp, path, sflags, vp_ret);
if (fdat != AT_FDCWD)
fd_putfile(fdat);
out:
return error;
}
static int
open_setfp(struct lwp *l, file_t *fp, struct vnode *vp, int indx, int flags)
{
int error;
fp->f_flag = flags & FMASK;
fp->f_type = DTYPE_VNODE;
fp->f_ops = &vnops;
fp->f_vnode = vp;
if (flags & (O_EXLOCK | O_SHLOCK)) {
struct flock lf;
int type;
lf.l_whence = SEEK_SET;
lf.l_start = 0;
lf.l_len = 0;
if (flags & O_EXLOCK)
lf.l_type = F_WRLCK;
else
lf.l_type = F_RDLCK;
type = F_FLOCK;
if ((flags & FNONBLOCK) == 0)
type |= F_WAIT;
VOP_UNLOCK(vp);
error = VOP_ADVLOCK(vp, fp, F_SETLK, &lf, type);
if (error) {
(void) vn_close(vp, fp->f_flag, fp->f_cred);
fd_abort(l->l_proc, fp, indx);
return error;
}
vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
atomic_or_uint(&fp->f_flag, FHASLOCK);
}
if (flags & O_CLOEXEC)
fd_set_exclose(l, indx, true);
return 0;
}
static int
mount_update(struct lwp *l, struct vnode *vp, const char *path, int flags,
void *data, size_t *data_len)
{
struct mount *mp;
int error = 0, saved_flags;
mp = vp->v_mount;
saved_flags = mp->mnt_flag;
/* We can operate only on VV_ROOT nodes. */
if ((vp->v_vflag & VV_ROOT) == 0) {
error = EINVAL;
goto out;
}
/*
* We only allow the filesystem to be reloaded if it
* is currently mounted read-only. Additionally, we
* prevent read-write to read-only downgrades.
*/
if ((flags & (MNT_RELOAD | MNT_RDONLY)) != 0 &&
(mp->mnt_flag & MNT_RDONLY) == 0 &&
(mp->mnt_iflag & IMNT_CAN_RWTORO) == 0) {
error = EOPNOTSUPP; /* Needs translation */
goto out;
}
/*
* Enabling MNT_UNION requires a covered mountpoint and
* must not happen on the root mount.
*/
if ((flags & MNT_UNION) != 0 && mp->mnt_vnodecovered == NULLVP) {
error = EOPNOTSUPP;
goto out;
}
error = kauth_authorize_system(l->l_cred, KAUTH_SYSTEM_MOUNT,
KAUTH_REQ_SYSTEM_MOUNT_UPDATE, mp, KAUTH_ARG(flags), data);
if (error)
goto out;
error = vfs_suspend(mp, 0);
if (error)
goto out;
mutex_enter(mp->mnt_updating);
mp->mnt_flag &= ~MNT_OP_FLAGS;
mp->mnt_flag |= flags & MNT_OP_FLAGS;
/*
* Set the mount level flags.
*/
if ((flags & MNT_RDONLY) != (mp->mnt_flag & MNT_RDONLY)) {
if ((flags & MNT_RDONLY))
mp->mnt_iflag |= IMNT_WANTRDONLY;
else
mp->mnt_iflag |= IMNT_WANTRDWR;
}
mp->mnt_flag &= ~MNT_BASIC_FLAGS;
mp->mnt_flag |= flags & MNT_BASIC_FLAGS;
if ((mp->mnt_iflag & IMNT_WANTRDONLY))
mp->mnt_flag &= ~MNT_RDONLY;
error = VFS_MOUNT(mp, path, data, data_len);
if (error && data != NULL) {
int error2;
/*
* Update failed; let's try and see if it was an
* export request. For compat with 3.0 and earlier.
*/
error2 = vfs_hooks_reexport(mp, path, data);
/*
* Only update error code if the export request was
* understood but some problem occurred while
* processing it.
*/
if (error2 != EJUSTRETURN)
error = error2;
}
if (error == 0 && (mp->mnt_iflag & IMNT_WANTRDONLY))
mp->mnt_flag |= MNT_RDONLY;
if (error)
mp->mnt_flag = saved_flags;
mp->mnt_flag &= ~MNT_OP_FLAGS;
mp->mnt_iflag &= ~(IMNT_WANTRDONLY | IMNT_WANTRDWR);
if ((mp->mnt_flag & (MNT_RDONLY | MNT_ASYNC)) == 0) {
if ((mp->mnt_iflag & IMNT_ONWORKLIST) == 0)
vfs_syncer_add_to_worklist(mp);
} else {
if ((mp->mnt_iflag & IMNT_ONWORKLIST) != 0)
vfs_syncer_remove_from_worklist(mp);
}
mutex_exit(mp->mnt_updating);
vfs_resume(mp);
if ((error == 0) && !(saved_flags & MNT_EXTATTR) &&
(flags & MNT_EXTATTR)) {
if (VFS_EXTATTRCTL(mp, EXTATTR_CMD_START,
NULL, 0, NULL) != 0) {
printf("%s: failed to start extattr, error = %d",
mp->mnt_stat.f_mntonname, error);
mp->mnt_flag &= ~MNT_EXTATTR;
}
}
if ((error == 0) && (saved_flags & MNT_EXTATTR) &&
!(flags & MNT_EXTATTR)) {
if (VFS_EXTATTRCTL(mp, EXTATTR_CMD_STOP,
NULL, 0, NULL) != 0) {
printf("%s: failed to stop extattr, error = %d",
mp->mnt_stat.f_mntonname, error);
mp->mnt_flag |= MNT_RDONLY;
}
}
out:
return (error);
}
static int
mount_get_vfsops(const char *fstype, enum uio_seg type_seg,
struct vfsops **vfsops)
{
char fstypename[sizeof(((struct statvfs *)NULL)->f_fstypename)];
int error;
if (type_seg == UIO_USERSPACE) {
/* Copy file-system type from userspace. */
error = copyinstr(fstype, fstypename, sizeof(fstypename), NULL);
} else {
error = copystr(fstype, fstypename, sizeof(fstypename), NULL);
KASSERT(error == 0);
}
if (error) {
/*
* Historically, filesystem types were identified by numbers.
* If we get an integer for the filesystem type instead of a
* string, we check to see if it matches one of the historic
* filesystem types.
*/
u_long fsindex = (u_long)fstype;
if (fsindex >= nmountcompatnames ||
mountcompatnames[fsindex] == NULL)
return ENODEV;
strlcpy(fstypename, mountcompatnames[fsindex],
sizeof(fstypename));
}
/* Accept `ufs' as an alias for `ffs', for compatibility. */
if (strcmp(fstypename, "ufs") == 0)
fstypename[0] = 'f';
if ((*vfsops = vfs_getopsbyname(fstypename)) != NULL)
return 0;
/* If we can autoload a vfs module, try again */
(void)module_autoload(fstypename, MODULE_CLASS_VFS);
if ((*vfsops = vfs_getopsbyname(fstypename)) != NULL)
return 0;
return ENODEV;
}
static int
mount_getargs(struct lwp *l, struct vnode *vp, const char *path, int flags,
void *data, size_t *data_len)
{
struct mount *mp;
int error;
/* If MNT_GETARGS is specified, it should be the only flag. */
if (flags & ~MNT_GETARGS)
return EINVAL;
mp = vp->v_mount;
/* XXX: probably some notion of "can see" here if we want isolation. */
error = kauth_authorize_system(l->l_cred, KAUTH_SYSTEM_MOUNT,
KAUTH_REQ_SYSTEM_MOUNT_GET, mp, data, NULL);
if (error)
return error;
if ((vp->v_vflag & VV_ROOT) == 0)
return EINVAL;
if (vfs_busy(mp))
return EPERM;
mutex_enter(mp->mnt_updating);
mp->mnt_flag &= ~MNT_OP_FLAGS;
mp->mnt_flag |= MNT_GETARGS;
error = VFS_MOUNT(mp, path, data, data_len);
mp->mnt_flag &= ~MNT_OP_FLAGS;
mutex_exit(mp->mnt_updating);
vfs_unbusy(mp);
return (error);
}
int
sys___mount50(struct lwp *l, const struct sys___mount50_args *uap, register_t *retval)
{
/* {
syscallarg(const char *) type;
syscallarg(const char *) path;
syscallarg(int) flags;
syscallarg(void *) data;
syscallarg(size_t) data_len;
} */
return do_sys_mount(l, SCARG(uap, type), UIO_USERSPACE, SCARG(uap, path),
SCARG(uap, flags), SCARG(uap, data), UIO_USERSPACE,
SCARG(uap, data_len), retval);
}
int
do_sys_mount(struct lwp *l, const char *type, enum uio_seg type_seg,
const char *path, int flags, void *data, enum uio_seg data_seg,
size_t data_len, register_t *retval)
{
struct vfsops *vfsops = NULL; /* XXX gcc4.8 */
struct vnode *vp;
void *data_buf = data;
bool vfsopsrele = false;
size_t alloc_sz = 0;
int error;
/*
* Get vnode to be covered
*/
error = namei_simple_user(path, NSM_FOLLOW_TRYEMULROOT, &vp);
if (error != 0) {
vp = NULL;
goto done;
}
if (flags & (MNT_GETARGS | MNT_UPDATE)) {
vfsops = vp->v_mount->mnt_op;
} else {
/* 'type' is userspace */
error = mount_get_vfsops(type, type_seg, &vfsops);
if (error != 0)
goto done;
vfsopsrele = true;
}
/*
* We allow data to be NULL, even for userspace. Some fs's don't need
* it. The others will handle NULL.
*/
if (data != NULL && data_seg == UIO_USERSPACE) {
if (data_len == 0) {
/* No length supplied, use default for filesystem */
data_len = vfsops->vfs_min_mount_data;
/*
* Hopefully a longer buffer won't make copyin() fail.
* For compatibility with 3.0 and earlier.
*/
if (flags & MNT_UPDATE
&& data_len < sizeof (struct mnt_export_args30))
data_len = sizeof (struct mnt_export_args30);
}
if ((data_len == 0) || (data_len > VFS_MAX_MOUNT_DATA)) {
error = EINVAL;
goto done;
}
alloc_sz = data_len;
data_buf = kmem_alloc(alloc_sz, KM_SLEEP);
/* NFS needs the buffer even for mnt_getargs .... */
error = copyin(data, data_buf, data_len);
if (error != 0)
goto done;
}
if (flags & MNT_GETARGS) {
if (data_len == 0) {
error = EINVAL;
goto done;
}
error = mount_getargs(l, vp, path, flags, data_buf, &data_len);
if (error != 0)
goto done;
if (data_seg == UIO_USERSPACE)
error = copyout(data_buf, data, data_len);
*retval = data_len;
} else if (flags & MNT_UPDATE) {
error = mount_update(l, vp, path, flags, data_buf, &data_len);
} else {
/* Locking is handled internally in mount_domount(). */
KASSERT(vfsopsrele == true);
error = mount_domount(l, &vp, vfsops, path, flags, data_buf,
&data_len);
vfsopsrele = false;
}
if (!error) {
mutex_enter(&fs_klist_lock);
KNOTE(&fs_klist, NOTE_SUBMIT | VQ_MOUNT);
mutex_exit(&fs_klist_lock);
}
done:
if (vfsopsrele)
vfs_delref(vfsops);
if (vp != NULL) {
vrele(vp);
}
if (data_buf != data)
kmem_free(data_buf, alloc_sz);
return (error);
}
/*
* Unmount a file system.
*
* Note: unmount takes a path to the vnode mounted on as argument,
* not special file (as before).
*/
/* ARGSUSED */
int
sys_unmount(struct lwp *l, const struct sys_unmount_args *uap, register_t *retval)
{
/* {
syscallarg(const char *) path;
syscallarg(int) flags;
} */
struct vnode *vp;
struct mount *mp;
int error;
struct pathbuf *pb;
struct nameidata nd;
error = pathbuf_copyin(SCARG(uap, path), &pb);
if (error) {
return error;
}
NDINIT(&nd, LOOKUP, NOFOLLOW | LOCKLEAF | TRYEMULROOT, pb);
if ((error = namei(&nd)) != 0) {
pathbuf_destroy(pb);
return error;
}
vp = nd.ni_vp;
pathbuf_destroy(pb);
mp = vp->v_mount;
vfs_ref(mp);
VOP_UNLOCK(vp);
error = kauth_authorize_system(l->l_cred, KAUTH_SYSTEM_MOUNT,
KAUTH_REQ_SYSTEM_MOUNT_UNMOUNT, mp, NULL, NULL);
if (error) {
vrele(vp);
vfs_rele(mp);
return (error);
}
/*
* Don't allow unmounting the root file system.
*/
if (mp->mnt_flag & MNT_ROOTFS) {
vrele(vp);
vfs_rele(mp);
return (EINVAL);
}
/*
* Must be the root of the filesystem
*/
if ((vp->v_vflag & VV_ROOT) == 0) {
vrele(vp);
vfs_rele(mp);
return (EINVAL);
}
vrele(vp);
error = dounmount(mp, SCARG(uap, flags), l);
vfs_rele(mp);
if (!error) {
mutex_enter(&fs_klist_lock);
KNOTE(&fs_klist, NOTE_SUBMIT | VQ_UNMOUNT);
mutex_exit(&fs_klist_lock);
}
return error;
}
/*
* Sync each mounted filesystem.
*/
#ifdef DEBUG
int syncprt = 0;
struct ctldebug debug0 = { "syncprt", &syncprt };
#endif
void
do_sys_sync(struct lwp *l)
{
mount_iterator_t *iter;
struct mount *mp;
int asyncflag;
mountlist_iterator_init(&iter);
while ((mp = mountlist_iterator_next(iter)) != NULL) {
mutex_enter(mp->mnt_updating);
if ((mp->mnt_flag & MNT_RDONLY) == 0) {
asyncflag = mp->mnt_flag & MNT_ASYNC;
mp->mnt_flag &= ~MNT_ASYNC;
VFS_SYNC(mp, MNT_NOWAIT, l->l_cred);
if (asyncflag)
mp->mnt_flag |= MNT_ASYNC;
}
mutex_exit(mp->mnt_updating);
}
mountlist_iterator_destroy(iter);
#ifdef DEBUG
if (syncprt)
vfs_bufstats();
#endif /* DEBUG */
}
static bool
sync_vnode_filter(void *cookie, vnode_t *vp)
{
if (vp->v_numoutput > 0) {
++*(int *)cookie;
}
return false;
}
int
vfs_syncwait(void)
{
int nbusy, nbusy_prev, iter;
struct vnode_iterator *vniter;
mount_iterator_t *mpiter;
struct mount *mp;
for (nbusy_prev = 0, iter = 0; iter < 20;) {
nbusy = 0;
mountlist_iterator_init(&mpiter);
while ((mp = mountlist_iterator_next(mpiter)) != NULL) {
vnode_t *vp __diagused;
vfs_vnode_iterator_init(mp, &vniter);
vp = vfs_vnode_iterator_next(vniter,
sync_vnode_filter, &nbusy);
KASSERT(vp == NULL);
vfs_vnode_iterator_destroy(vniter);
}
mountlist_iterator_destroy(mpiter);
if (nbusy == 0)
break;
if (nbusy_prev == 0)
nbusy_prev = nbusy;
printf("%d ", nbusy);
kpause("syncwait", false, MAX(1, hz / 25 * iter), NULL);
if (nbusy >= nbusy_prev) /* we didn't flush anything */
iter++;
else
nbusy_prev = nbusy;
}
if (nbusy) {
#if defined(DEBUG) || defined(DEBUG_HALT_BUSY)
printf("giving up\nPrinting vnodes for busy buffers\n");
mountlist_iterator_init(&mpiter);
while ((mp = mountlist_iterator_next(mpiter)) != NULL) {
vnode_t *vp;
vfs_vnode_iterator_init(mp, &vniter);
vp = vfs_vnode_iterator_next(vniter,
NULL, NULL);
mutex_enter(vp->v_interlock);
if (vp->v_numoutput > 0)
vprint(NULL, vp);
mutex_exit(vp->v_interlock);
vrele(vp);
vfs_vnode_iterator_destroy(vniter);
}
mountlist_iterator_destroy(mpiter);
#endif
}
return nbusy;
}
/* ARGSUSED */
int
sys_sync(struct lwp *l, const void *v, register_t *retval)
{
do_sys_sync(l);
return (0);
}
/*
* Access or change filesystem quotas.
*
* (this is really 14 different calls bundled into one)
*/
static int
do_sys_quotactl_stat(struct mount *mp, struct quotastat *info_u)
{
struct quotastat info_k;
int error;
/* ensure any padding bytes are cleared */
memset(&info_k, 0, sizeof(info_k));
error = vfs_quotactl_stat(mp, &info_k);
if (error) {
return error;
}
return copyout(&info_k, info_u, sizeof(info_k));
}
static int
do_sys_quotactl_idtypestat(struct mount *mp, int idtype,
struct quotaidtypestat *info_u)
{
struct quotaidtypestat info_k;
int error;
/* ensure any padding bytes are cleared */
memset(&info_k, 0, sizeof(info_k));
error = vfs_quotactl_idtypestat(mp, idtype, &info_k);
if (error) {
return error;
}
return copyout(&info_k, info_u, sizeof(info_k));
}
static int
do_sys_quotactl_objtypestat(struct mount *mp, int objtype,
struct quotaobjtypestat *info_u)
{
struct quotaobjtypestat info_k;
int error;
/* ensure any padding bytes are cleared */
memset(&info_k, 0, sizeof(info_k));
error = vfs_quotactl_objtypestat(mp, objtype, &info_k);
if (error) {
return error;
}
return copyout(&info_k, info_u, sizeof(info_k));
}
static int
do_sys_quotactl_get(struct mount *mp, const struct quotakey *key_u,
struct quotaval *val_u)
{
struct quotakey key_k;
struct quotaval val_k;
int error;
/* ensure any padding bytes are cleared */
memset(&val_k, 0, sizeof(val_k));
error = copyin(key_u, &key_k, sizeof(key_k));
if (error) {
return error;
}
error = vfs_quotactl_get(mp, &key_k, &val_k);
if (error) {
return error;
}
return copyout(&val_k, val_u, sizeof(val_k));
}
static int
do_sys_quotactl_put(struct mount *mp, const struct quotakey *key_u,
const struct quotaval *val_u)
{
struct quotakey key_k;
struct quotaval val_k;
int error;
error = copyin(key_u, &key_k, sizeof(key_k));
if (error) {
return error;
}
error = copyin(val_u, &val_k, sizeof(val_k));
if (error) {
return error;
}
return vfs_quotactl_put(mp, &key_k, &val_k);
}
static int
do_sys_quotactl_del(struct mount *mp, const struct quotakey *key_u)
{
struct quotakey key_k;
int error;
error = copyin(key_u, &key_k, sizeof(key_k));
if (error) {
return error;
}
return vfs_quotactl_del(mp, &key_k);
}
static int
do_sys_quotactl_cursoropen(struct mount *mp, struct quotakcursor *cursor_u)
{
struct quotakcursor cursor_k;
int error;
/* ensure any padding bytes are cleared */
memset(&cursor_k, 0, sizeof(cursor_k));
error = vfs_quotactl_cursoropen(mp, &cursor_k);
if (error) {
return error;
}
return copyout(&cursor_k, cursor_u, sizeof(cursor_k));
}
static int
do_sys_quotactl_cursorclose(struct mount *mp, struct quotakcursor *cursor_u)
{
struct quotakcursor cursor_k;
int error;
error = copyin(cursor_u, &cursor_k, sizeof(cursor_k));
if (error) {
return error;
}
return vfs_quotactl_cursorclose(mp, &cursor_k);
}
static int
do_sys_quotactl_cursorskipidtype(struct mount *mp,
struct quotakcursor *cursor_u, int idtype)
{
struct quotakcursor cursor_k;
int error;
error = copyin(cursor_u, &cursor_k, sizeof(cursor_k));
if (error) {
return error;
}
error = vfs_quotactl_cursorskipidtype(mp, &cursor_k, idtype);
if (error) {
return error;
}
return copyout(&cursor_k, cursor_u, sizeof(cursor_k));
}
static int
do_sys_quotactl_cursorget(struct mount *mp, struct quotakcursor *cursor_u,
struct quotakey *keys_u, struct quotaval *vals_u, unsigned maxnum,
unsigned *ret_u)
{
#define CGET_STACK_MAX 8
struct quotakcursor cursor_k;
struct quotakey stackkeys[CGET_STACK_MAX];
struct quotaval stackvals[CGET_STACK_MAX];
struct quotakey *keys_k;
struct quotaval *vals_k;
unsigned ret_k;
int error;
if (maxnum > 128) {
maxnum = 128;
}
error = copyin(cursor_u, &cursor_k, sizeof(cursor_k));