fs_subr.c revision f48205be61a214698b763ff550ab9e657525104c
/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License (the "License").
* You may not use this file except in compliance with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* or http://www.opensolaris.org/os/licensing.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
/* Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T */
/* All Rights Reserved */
/*
* Copyright 2007 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
#pragma ident "%Z%%M% %I% %E% SMI"
/*
* Generic vnode operations.
*/
#include <sys/types.h>
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/errno.h>
#include <sys/fcntl.h>
#include <sys/flock.h>
#include <sys/statvfs.h>
#include <sys/vfs.h>
#include <sys/vnode.h>
#include <sys/proc.h>
#include <sys/user.h>
#include <sys/unistd.h>
#include <sys/cred.h>
#include <sys/poll.h>
#include <sys/debug.h>
#include <sys/cmn_err.h>
#include <sys/stream.h>
#include <fs/fs_subr.h>
#include <sys/acl.h>
#include <sys/share.h>
#include <sys/file.h>
#include <sys/kmem.h>
#include <sys/file.h>
#include <sys/nbmlock.h>
#include <acl/acl_common.h>
static callb_cpr_t *frlock_serialize_blocked(flk_cb_when_t, void *);
/*
* Tunable to limit the number of retry to recover from STALE error.
*/
int fs_estale_retry = 5;
/*
* The associated operation is not supported by the file system.
*/
int
fs_nosys()
{
return (ENOSYS);
}
/*
* The associated operation is invalid (on this vnode).
*/
int
fs_inval()
{
return (EINVAL);
}
/*
* The associated operation is valid only for directories.
*/
int
fs_notdir()
{
return (ENOTDIR);
}
/*
* Free the file system specific resources. For the file systems that
* do not support the forced unmount, it will be a nop function.
*/
/*ARGSUSED*/
void
fs_freevfs(vfs_t *vfsp)
{
}
/* ARGSUSED */
int
fs_nosys_map(struct vnode *vp,
offset_t off,
struct as *as,
caddr_t *addrp,
size_t len,
uchar_t prot,
uchar_t maxprot,
uint_t flags,
struct cred *cr)
{
return (ENOSYS);
}
/* ARGSUSED */
int
fs_nosys_addmap(struct vnode *vp,
offset_t off,
struct as *as,
caddr_t addr,
size_t len,
uchar_t prot,
uchar_t maxprot,
uint_t flags,
struct cred *cr)
{
return (ENOSYS);
}
/* ARGSUSED */
int
fs_nosys_poll(vnode_t *vp,
register short events,
int anyyet,
register short *reventsp,
struct pollhead **phpp)
{
return (ENOSYS);
}
/*
* The file system has nothing to sync to disk. However, the
* VFS_SYNC operation must not fail.
*/
/* ARGSUSED */
int
fs_sync(struct vfs *vfspp, short flag, cred_t *cr)
{
return (0);
}
/*
* Read/write lock/unlock. Does nothing.
*/
/* ARGSUSED */
int
fs_rwlock(vnode_t *vp, int write_lock, caller_context_t *ctp)
{
return (-1);
}
/* ARGSUSED */
void
fs_rwunlock(vnode_t *vp, int write_lock, caller_context_t *ctp)
{
}
/*
* Compare two vnodes.
*/
int
fs_cmp(vnode_t *vp1, vnode_t *vp2)
{
return (vp1 == vp2);
}
/*
* No-op seek operation.
*/
/* ARGSUSED */
int
fs_seek(vnode_t *vp, offset_t ooff, offset_t *noffp)
{
return ((*noffp < 0 || *noffp > MAXOFFSET_T) ? EINVAL : 0);
}
/*
* File and record locking.
*/
/* ARGSUSED */
int
fs_frlock(register vnode_t *vp, int cmd, struct flock64 *bfp, int flag,
offset_t offset, flk_callback_t *flk_cbp, cred_t *cr)
{
int frcmd;
int nlmid;
int error = 0;
flk_callback_t serialize_callback;
int serialize = 0;
switch (cmd) {
case F_GETLK:
case F_O_GETLK:
if (flag & F_REMOTELOCK) {
frcmd = RCMDLCK;
break;
}
if (flag & F_PXFSLOCK) {
frcmd = PCMDLCK;
break;
}
bfp->l_pid = ttoproc(curthread)->p_pid;
bfp->l_sysid = 0;
frcmd = 0;
break;
case F_SETLK_NBMAND:
/*
* Are NBMAND locks allowed on this file?
*/
if (!vp->v_vfsp ||
!(vp->v_vfsp->vfs_flag & VFS_NBMAND)) {
error = EINVAL;
goto done;
}
if (vp->v_type != VREG) {
error = EINVAL;
goto done;
}
/*FALLTHROUGH*/
case F_SETLK:
/*
* Check whether there is an NBMAND share reservation that
* conflicts with the lock request.
*/
if (nbl_need_check(vp)) {
nbl_start_crit(vp, RW_WRITER);
serialize = 1;
if (share_blocks_lock(vp, bfp)) {
error = EAGAIN;
goto done;
}
}
if (flag & F_REMOTELOCK) {
frcmd = SETFLCK|RCMDLCK;
break;
}
if (flag & F_PXFSLOCK) {
frcmd = SETFLCK|PCMDLCK;
break;
}
bfp->l_pid = ttoproc(curthread)->p_pid;
bfp->l_sysid = 0;
frcmd = SETFLCK;
if (cmd == F_SETLK_NBMAND &&
(bfp->l_type == F_RDLCK || bfp->l_type == F_WRLCK)) {
/* would check here for conflict with mapped region */
frcmd |= NBMLCK;
}
break;
case F_SETLKW:
/*
* If there is an NBMAND share reservation that conflicts
* with the lock request, block until the conflicting share
* reservation goes away.
*/
if (nbl_need_check(vp)) {
nbl_start_crit(vp, RW_WRITER);
serialize = 1;
if (share_blocks_lock(vp, bfp)) {
error = wait_for_share(vp, bfp);
if (error != 0)
goto done;
}
}
if (flag & F_REMOTELOCK) {
frcmd = SETFLCK|SLPFLCK|RCMDLCK;
break;
}
if (flag & F_PXFSLOCK) {
frcmd = SETFLCK|SLPFLCK|PCMDLCK;
break;
}
bfp->l_pid = ttoproc(curthread)->p_pid;
bfp->l_sysid = 0;
frcmd = SETFLCK|SLPFLCK;
break;
case F_HASREMOTELOCKS:
nlmid = GETNLMID(bfp->l_sysid);
if (nlmid != 0) { /* booted as a cluster */
l_has_rmt(bfp) =
cl_flk_has_remote_locks_for_nlmid(vp, nlmid);
} else { /* not booted as a cluster */
l_has_rmt(bfp) = flk_has_remote_locks(vp);
}
goto done;
default:
error = EINVAL;
goto done;
}
/*
* If this is a blocking lock request and we're serializing lock
* requests, modify the callback list to leave the critical region
* while we're waiting for the lock.
*/
if (serialize && (frcmd & SLPFLCK) != 0) {
flk_add_callback(&serialize_callback,
frlock_serialize_blocked, vp, flk_cbp);
flk_cbp = &serialize_callback;
}
error = reclock(vp, bfp, frcmd, flag, offset, flk_cbp);
done:
if (serialize)
nbl_end_crit(vp);
return (error);
}
/*
* Callback when a lock request blocks and we are serializing requests. If
* before sleeping, leave the critical region. If after wakeup, reenter
* the critical region.
*/
static callb_cpr_t *
frlock_serialize_blocked(flk_cb_when_t when, void *infop)
{
vnode_t *vp = (vnode_t *)infop;
if (when == FLK_BEFORE_SLEEP)
nbl_end_crit(vp);
else {
nbl_start_crit(vp, RW_WRITER);
}
return (NULL);
}
/*
* Allow any flags.
*/
/* ARGSUSED */
int
fs_setfl(vnode_t *vp, int oflags, int nflags, cred_t *cr)
{
return (0);
}
/*
* Return the answer requested to poll() for non-device files.
* Only POLLIN, POLLRDNORM, and POLLOUT are recognized.
*/
struct pollhead fs_pollhd;
/* ARGSUSED */
int
fs_poll(vnode_t *vp,
register short events,
int anyyet,
register short *reventsp,
struct pollhead **phpp)
{
*reventsp = 0;
if (events & POLLIN)
*reventsp |= POLLIN;
if (events & POLLRDNORM)
*reventsp |= POLLRDNORM;
if (events & POLLRDBAND)
*reventsp |= POLLRDBAND;
if (events & POLLOUT)
*reventsp |= POLLOUT;
if (events & POLLWRBAND)
*reventsp |= POLLWRBAND;
*phpp = !anyyet && !*reventsp ? &fs_pollhd : (struct pollhead *)NULL;
return (0);
}
/*
* POSIX pathconf() support.
*/
/* ARGSUSED */
int
fs_pathconf(vnode_t *vp, int cmd, ulong_t *valp, cred_t *cr)
{
register ulong_t val;
register int error = 0;
struct statvfs64 vfsbuf;
switch (cmd) {
case _PC_LINK_MAX:
val = MAXLINK;
break;
case _PC_MAX_CANON:
val = MAX_CANON;
break;
case _PC_MAX_INPUT:
val = MAX_INPUT;
break;
case _PC_NAME_MAX:
bzero(&vfsbuf, sizeof (vfsbuf));
if (error = VFS_STATVFS(vp->v_vfsp, &vfsbuf))
break;
val = vfsbuf.f_namemax;
break;
case _PC_PATH_MAX:
case _PC_SYMLINK_MAX:
val = MAXPATHLEN;
break;
case _PC_PIPE_BUF:
val = PIPE_BUF;
break;
case _PC_NO_TRUNC:
if (vp->v_vfsp->vfs_flag & VFS_NOTRUNC)
val = 1; /* NOTRUNC is enabled for vp */
else
val = (ulong_t)-1;
break;
case _PC_VDISABLE:
val = _POSIX_VDISABLE;
break;
case _PC_CHOWN_RESTRICTED:
if (rstchown)
val = rstchown; /* chown restricted enabled */
else
val = (ulong_t)-1;
break;
case _PC_FILESIZEBITS:
/*
* If ever we come here it means that underlying file system
* does not recognise the command and therefore this
* configurable limit cannot be determined. We return -1
* and don't change errno.
*/
val = (ulong_t)-1; /* large file support */
break;
case _PC_ACL_ENABLED:
val = 0;
break;
default:
error = EINVAL;
break;
}
if (error == 0)
*valp = val;
return (error);
}
/*
* Dispose of a page.
*/
/* ARGSUSED */
void
fs_dispose(struct vnode *vp, page_t *pp, int fl, int dn, struct cred *cr)
{
ASSERT(fl == B_FREE || fl == B_INVAL);
if (fl == B_FREE)
page_free(pp, dn);
else
page_destroy(pp, dn);
}
/* ARGSUSED */
void
fs_nodispose(struct vnode *vp, page_t *pp, int fl, int dn, struct cred *cr)
{
cmn_err(CE_PANIC, "fs_nodispose invoked");
}
/*
* fabricate acls for file systems that do not support acls.
*/
/* ARGSUSED */
int
fs_fab_acl(vp, vsecattr, flag, cr)
vnode_t *vp;
vsecattr_t *vsecattr;
int flag;
cred_t *cr;
{
aclent_t *aclentp;
ace_t *acep;
struct vattr vattr;
int error;
vsecattr->vsa_aclcnt = 0;
vsecattr->vsa_aclentp = NULL;
vsecattr->vsa_dfaclcnt = 0; /* Default ACLs are not fabricated */
vsecattr->vsa_dfaclentp = NULL;
vattr.va_mask = AT_MODE | AT_UID | AT_GID;
if (error = VOP_GETATTR(vp, &vattr, 0, cr))
return (error);
if (vsecattr->vsa_mask & (VSA_ACLCNT | VSA_ACL)) {
vsecattr->vsa_aclcnt = 4; /* USER, GROUP, OTHER, and CLASS */
vsecattr->vsa_aclentp = kmem_zalloc(4 * sizeof (aclent_t),
KM_SLEEP);
aclentp = vsecattr->vsa_aclentp;
aclentp->a_type = USER_OBJ; /* Owner */
aclentp->a_perm = ((ushort_t)(vattr.va_mode & 0700)) >> 6;
aclentp->a_id = vattr.va_uid; /* Really undefined */
aclentp++;
aclentp->a_type = GROUP_OBJ; /* Group */
aclentp->a_perm = ((ushort_t)(vattr.va_mode & 0070)) >> 3;
aclentp->a_id = vattr.va_gid; /* Really undefined */
aclentp++;
aclentp->a_type = OTHER_OBJ; /* Other */
aclentp->a_perm = vattr.va_mode & 0007;
aclentp->a_id = (gid_t)-1; /* Really undefined */
aclentp++;
aclentp->a_type = CLASS_OBJ; /* Class */
aclentp->a_perm = (ushort_t)(0007);
aclentp->a_id = (gid_t)-1; /* Really undefined */
} else if (vsecattr->vsa_mask & (VSA_ACECNT | VSA_ACE)) {
vsecattr->vsa_aclcnt = 6;
vsecattr->vsa_aclentp = kmem_zalloc(6 * sizeof (ace_t),
KM_SLEEP);
acep = vsecattr->vsa_aclentp;
(void) memcpy(acep, trivial_acl, sizeof (ace_t) * 6);
adjust_ace_pair(acep, (vattr.va_mode & 0700) >> 6);
adjust_ace_pair(acep + 2, (vattr.va_mode & 0070) >> 3);
adjust_ace_pair(acep + 4, vattr.va_mode & 0007);
}
return (0);
}
/*
* Common code for implementing DOS share reservations
*/
/* ARGSUSED4 */
int
fs_shrlock(struct vnode *vp, int cmd, struct shrlock *shr, int flag, cred_t *cr)
{
int error;
/*
* Make sure that the file was opened with permissions appropriate
* for the request, and make sure the caller isn't trying to sneak
* in an NBMAND request.
*/
if (cmd == F_SHARE) {
if (((shr->s_access & F_RDACC) && (flag & FREAD) == 0) ||
((shr->s_access & F_WRACC) && (flag & FWRITE) == 0))
return (EBADF);
if (shr->s_deny & F_MANDDNY)
return (EINVAL);
}
if (cmd == F_SHARE_NBMAND) {
/* must have write permission to deny read access */
if ((shr->s_deny & F_RDDNY) && (flag & FWRITE) == 0)
return (EBADF);
/* make sure nbmand is allowed on the file */
if (!vp->v_vfsp ||
!(vp->v_vfsp->vfs_flag & VFS_NBMAND)) {
return (EINVAL);
}
if (vp->v_type != VREG) {
return (EINVAL);
}
}
nbl_start_crit(vp, RW_WRITER);
switch (cmd) {
case F_SHARE_NBMAND:
shr->s_deny |= F_MANDDNY;
/*FALLTHROUGH*/
case F_SHARE:
error = add_share(vp, shr);
break;
case F_UNSHARE:
error = del_share(vp, shr);
break;
case F_HASREMOTELOCKS:
/*
* We are overloading this command to refer to remote
* shares as well as remote locks, despite its name.
*/
shr->s_access = shr_has_remote_shares(vp, shr->s_sysid);
error = 0;
break;
default:
error = EINVAL;
break;
}
nbl_end_crit(vp);
return (error);
}
/*ARGSUSED1*/
int
fs_vnevent_nosupport(vnode_t *vp, vnevent_t vnevent)
{
ASSERT(vp != NULL);
return (ENOTSUP);
}
/*ARGSUSED1*/
int
fs_vnevent_support(vnode_t *vp, vnevent_t vnevent)
{
ASSERT(vp != NULL);
return (0);
}
/*
* return 1 for non-trivial ACL.
*
* NB: It is not necessary for the caller to VOP_RWLOCK since
* we only issue VOP_GETSECATTR.
*
* Returns 0 == trivial
* 1 == NOT Trivial
* <0 could not determine.
*/
int
fs_acl_nontrivial(vnode_t *vp, cred_t *cr)
{
ulong_t acl_styles;
ulong_t acl_flavor;
vsecattr_t vsecattr;
int error;
int isnontrivial;
/* determine the forms of ACLs maintained */
error = VOP_PATHCONF(vp, _PC_ACL_ENABLED, &acl_styles, cr);
/* clear bits we don't understand and establish default acl_style */
acl_styles &= (_ACL_ACLENT_ENABLED | _ACL_ACE_ENABLED);
if (error || (acl_styles == 0))
acl_styles = _ACL_ACLENT_ENABLED;
vsecattr.vsa_aclentp = NULL;
vsecattr.vsa_dfaclentp = NULL;
vsecattr.vsa_aclcnt = 0;
vsecattr.vsa_dfaclcnt = 0;
while (acl_styles) {
/* select one of the styles as current flavor */
acl_flavor = 0;
if (acl_styles & _ACL_ACLENT_ENABLED) {
acl_flavor = _ACL_ACLENT_ENABLED;
vsecattr.vsa_mask = VSA_ACLCNT | VSA_DFACLCNT;
} else if (acl_styles & _ACL_ACE_ENABLED) {
acl_flavor = _ACL_ACE_ENABLED;
vsecattr.vsa_mask = VSA_ACECNT | VSA_ACE;
}
ASSERT(vsecattr.vsa_mask && acl_flavor);
error = VOP_GETSECATTR(vp, &vsecattr, 0, cr);
if (error == 0)
break;
/* that flavor failed */
acl_styles &= ~acl_flavor;
}
/* if all styles fail then assume trivial */
if (acl_styles == 0)
return (0);
/* process the flavor that worked */
isnontrivial = 0;
if (acl_flavor & _ACL_ACLENT_ENABLED) {
if (vsecattr.vsa_aclcnt > MIN_ACL_ENTRIES)
isnontrivial = 1;
if (vsecattr.vsa_aclcnt && vsecattr.vsa_aclentp != NULL)
kmem_free(vsecattr.vsa_aclentp,
vsecattr.vsa_aclcnt * sizeof (aclent_t));
if (vsecattr.vsa_dfaclcnt && vsecattr.vsa_dfaclentp != NULL)
kmem_free(vsecattr.vsa_dfaclentp,
vsecattr.vsa_dfaclcnt * sizeof (aclent_t));
}
if (acl_flavor & _ACL_ACE_ENABLED) {
isnontrivial = ace_trivial(vsecattr.vsa_aclentp,
vsecattr.vsa_aclcnt);
if (vsecattr.vsa_aclcnt && vsecattr.vsa_aclentp != NULL)
kmem_free(vsecattr.vsa_aclentp,
vsecattr.vsa_aclcnt * sizeof (ace_t));
/* ACE has no vsecattr.vsa_dfaclcnt */
}
return (isnontrivial);
}
/*
* Check whether we need a retry to recover from STALE error.
*/
int
fs_need_estale_retry(int retry_count)
{
if (retry_count < fs_estale_retry)
return (1);
else
return (0);
}