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minix/sys/ufs/lfs/ulfs_extattr.c
Lionel Sambuc 84d9c625bf Synchronize on NetBSD-CVS (2013/12/1 12:00:00 UTC) 
- Fix for possible unset uid/gid in toproto
 - Fix for default mtree style
 - Update libelf
 - Importing libexecinfo
 - Resynchronize GCC, mpc, gmp, mpfr
 - build.sh: Replace params with show-params.
     This has been done as the make target has been renamed in the same
     way, while a new target named params has been added. This new
     target generates a file containing all the parameters, instead of
     printing it on the console.
 - Update test48 with new etc/services (Fix by Ben Gras <ben@minix3.org)
     get getservbyport() out of the inner loop

Change-Id: Ie6ad5226fa2621ff9f0dee8782ea48f9443d2091
2014-07-28 17:05:06 +02:00

1596 lines
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/* $NetBSD: ulfs_extattr.c,v 1.6 2013/06/08 22:23:52 dholland Exp $ */
/* from NetBSD: ufs_extattr.c,v 1.41 2012/12/08 13:42:36 manu Exp */
/*-
* Copyright (c) 1999-2002 Robert N. M. Watson
* Copyright (c) 2002-2003 Networks Associates Technology, Inc.
* All rights reserved.
*
* This software was developed by Robert Watson for the TrustedBSD Project.
*
* This software was developed for the FreeBSD Project in part by Network
* Associates Laboratories, the Security Research Division of Network
* Associates, Inc. under DARPA/SPAWAR contract N66001-01-C-8035 ("CBOSS"),
* as part of the DARPA CHATS research program.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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.
*
*/
/*
* Support for file system extended attributes on the ULFS1 file system.
*
* Extended attributes are defined in the form name=value, where name is
* a nul-terminated string in the style of a file name, and value is a
* binary blob of zero or more bytes. The ULFS1 extended attribute service
* layers support for extended attributes onto a backing file, in the style
* of the quota implementation, meaning that it requires no underlying format
* changes to the file system. This design choice exchanges simplicity,
* usability, and easy deployment for performance.
*/
#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: ulfs_extattr.c,v 1.6 2013/06/08 22:23:52 dholland Exp $");
#ifdef _KERNEL_OPT
#include "opt_lfs.h"
#endif
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/reboot.h>
#include <sys/kauth.h>
#include <sys/kernel.h>
#include <sys/namei.h>
#include <sys/kmem.h>
#include <sys/fcntl.h>
#include <sys/lwp.h>
#include <sys/vnode.h>
#include <sys/mount.h>
#include <sys/lock.h>
#include <sys/dirent.h>
#include <sys/extattr.h>
#include <sys/sysctl.h>
#include <ufs/lfs/ulfs_extattr.h>
#include <ufs/lfs/ulfsmount.h>
#include <ufs/lfs/ulfs_inode.h>
#include <ufs/lfs/ulfs_bswap.h>
#include <ufs/lfs/ulfs_extern.h>
int ulfs_extattr_sync = 1;
int ulfs_extattr_autocreate = 1024;
static int ulfs_extattr_valid_attrname(int attrnamespace,
const char *attrname);
static int ulfs_extattr_enable_with_open(struct ulfsmount *ump,
struct vnode *vp, int attrnamespace, const char *attrname,
struct lwp *l);
static int ulfs_extattr_enable(struct ulfsmount *ump, int attrnamespace,
const char *attrname, struct vnode *backing_vnode,
struct lwp *l);
static int ulfs_extattr_disable(struct ulfsmount *ump, int attrnamespace,
const char *attrname, struct lwp *l);
static int ulfs_extattr_get(struct vnode *vp, int attrnamespace,
const char *name, struct uio *uio, size_t *size,
kauth_cred_t cred, struct lwp *l);
static int ulfs_extattr_list(struct vnode *vp, int attrnamespace,
struct uio *uio, size_t *size, int flag,
kauth_cred_t cred, struct lwp *l);
static int ulfs_extattr_set(struct vnode *vp, int attrnamespace,
const char *name, struct uio *uio, kauth_cred_t cred,
struct lwp *l);
static int ulfs_extattr_rm(struct vnode *vp, int attrnamespace,
const char *name, kauth_cred_t cred, struct lwp *l);
static struct ulfs_extattr_list_entry *ulfs_extattr_find_attr(struct ulfsmount *,
int, const char *);
static int ulfs_extattr_get_header(struct vnode *,
struct ulfs_extattr_list_entry *,
struct ulfs_extattr_header *, off_t *);
/*
* Convert a FreeBSD extended attribute and namespace to a consistent string
* representation.
*
* The returned value, if not NULL, is guaranteed to be an allocated object
* of its size as returned by strlen() + 1 and must be freed by the caller.
*/
static char *
from_freebsd_extattr(int attrnamespace, const char *attrname)
{
const char *namespace;
char *attr;
size_t len;
if (attrnamespace == EXTATTR_NAMESPACE_SYSTEM)
namespace = "system";
else if (attrnamespace == EXTATTR_NAMESPACE_USER)
namespace = "user";
else
return NULL;
/* <namespace>.<attrname>\0 */
len = strlen(namespace) + 1 + strlen(attrname) + 1;
attr = kmem_alloc(len, KM_SLEEP);
snprintf(attr, len, "%s.%s", namespace, attrname);
return attr;
}
/*
* Internal wrapper around a conversion-check-free sequence.
*/
static int
internal_extattr_check_cred(vnode_t *vp, int attrnamespace, const char *name,
kauth_cred_t cred, int access_mode)
{
char *attr;
int error;
attr = from_freebsd_extattr(attrnamespace, name);
if (attr == NULL)
return EINVAL;
error = extattr_check_cred(vp, attr, cred, access_mode);
kmem_free(attr, strlen(attr) + 1);
return error;
}
/*
* Per-FS attribute lock protecting attribute operations.
* XXX Right now there is a lot of lock contention due to having a single
* lock per-FS; really, this should be far more fine-grained.
*/
static void
ulfs_extattr_uepm_lock(struct ulfsmount *ump)
{
/* XXX Why does this need to be recursive? */
if (mutex_owned(&ump->um_extattr.uepm_lock)) {
ump->um_extattr.uepm_lockcnt++;
return;
}
mutex_enter(&ump->um_extattr.uepm_lock);
}
static void
ulfs_extattr_uepm_unlock(struct ulfsmount *ump)
{
if (ump->um_extattr.uepm_lockcnt != 0) {
KASSERT(mutex_owned(&ump->um_extattr.uepm_lock));
ump->um_extattr.uepm_lockcnt--;
return;
}
mutex_exit(&ump->um_extattr.uepm_lock);
}
/*-
* Determine whether the name passed is a valid name for an actual
* attribute.
*
* Invalid currently consists of:
* NULL pointer for attrname
* zero-length attrname (used to retrieve application attribute list)
*/
static int
ulfs_extattr_valid_attrname(int attrnamespace, const char *attrname)
{
if (attrname == NULL)
return (0);
if (strlen(attrname) == 0)
return (0);
return (1);
}
/*
* Autocreate an attribute storage
*/
static struct ulfs_extattr_list_entry *
ulfs_extattr_autocreate_attr(struct vnode *vp, int attrnamespace,
const char *attrname, struct lwp *l)
{
struct mount *mp = vp->v_mount;
struct ulfsmount *ump = VFSTOULFS(mp);
struct vnode *backing_vp;
struct nameidata nd;
struct pathbuf *pb;
char *path;
struct ulfs_extattr_fileheader uef;
struct ulfs_extattr_list_entry *uele;
int error;
path = PNBUF_GET();
/*
* We only support system and user namespace autocreation
*/
switch (attrnamespace) {
case EXTATTR_NAMESPACE_SYSTEM:
(void)snprintf(path, PATH_MAX, "%s/%s/%s/%s",
mp->mnt_stat.f_mntonname,
ULFS_EXTATTR_FSROOTSUBDIR,
ULFS_EXTATTR_SUBDIR_SYSTEM,
attrname);
break;
case EXTATTR_NAMESPACE_USER:
(void)snprintf(path, PATH_MAX, "%s/%s/%s/%s",
mp->mnt_stat.f_mntonname,
ULFS_EXTATTR_FSROOTSUBDIR,
ULFS_EXTATTR_SUBDIR_USER,
attrname);
break;
default:
PNBUF_PUT(path);
return NULL;
break;
}
/*
* XXX unlock/lock should only be done when setting extattr
* on backing store or one of its parent directory
* including root, but we always do it for now.
*/
KASSERT(VOP_ISLOCKED(vp) == LK_EXCLUSIVE);
VOP_UNLOCK(vp);
pb = pathbuf_create(path);
NDINIT(&nd, CREATE, LOCKPARENT, pb);
error = vn_open(&nd, O_CREAT|O_RDWR, 0600);
/*
* Reacquire the lock on the vnode
*/
KASSERT(VOP_ISLOCKED(vp) == 0);
vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
if (error != 0) {
pathbuf_destroy(pb);
PNBUF_PUT(path);
return NULL;
}
KASSERT(nd.ni_vp != NULL);
KASSERT(VOP_ISLOCKED(nd.ni_vp) == LK_EXCLUSIVE);
KASSERT(VOP_ISLOCKED(nd.ni_dvp) == 0);
/*
* backing_vp is the backing store.
*/
backing_vp = nd.ni_vp;
pathbuf_destroy(pb);
PNBUF_PUT(path);
uef.uef_magic = ULFS_EXTATTR_MAGIC;
uef.uef_version = ULFS_EXTATTR_VERSION;
uef.uef_size = ulfs_extattr_autocreate;
error = vn_rdwr(UIO_WRITE, backing_vp, &uef, sizeof(uef), 0,
UIO_SYSSPACE, IO_NODELOCKED|IO_APPEND,
l->l_cred, NULL, l);
VOP_UNLOCK(backing_vp);
if (error != 0) {
printf("%s: write uef header failed for %s, error = %d\n",
__func__, attrname, error);
vn_close(backing_vp, FREAD|FWRITE, l->l_cred);
return NULL;
}
/*
* Now enable attribute.
*/
error = ulfs_extattr_enable(ump,attrnamespace, attrname, backing_vp, l);
KASSERT(VOP_ISLOCKED(backing_vp) == 0);
if (error != 0) {
printf("%s: enable %s failed, error %d\n",
__func__, attrname, error);
vn_close(backing_vp, FREAD|FWRITE, l->l_cred);
return NULL;
}
uele = ulfs_extattr_find_attr(ump, attrnamespace, attrname);
if (uele == NULL) {
printf("%s: atttribute %s created but not found!\n",
__func__, attrname);
vn_close(backing_vp, FREAD|FWRITE, l->l_cred);
return NULL;
}
printf("%s: EA backing store autocreated for %s\n",
mp->mnt_stat.f_mntonname, attrname);
return uele;
}
/*
* Locate an attribute given a name and mountpoint.
* Must be holding uepm lock for the mount point.
*/
static struct ulfs_extattr_list_entry *
ulfs_extattr_find_attr(struct ulfsmount *ump, int attrnamespace,
const char *attrname)
{
struct ulfs_extattr_list_entry *search_attribute;
for (search_attribute = LIST_FIRST(&ump->um_extattr.uepm_list);
search_attribute != NULL;
search_attribute = LIST_NEXT(search_attribute, uele_entries)) {
if (!(strncmp(attrname, search_attribute->uele_attrname,
ULFS_EXTATTR_MAXEXTATTRNAME)) &&
(attrnamespace == search_attribute->uele_attrnamespace)) {
return (search_attribute);
}
}
return (0);
}
/*
* Initialize per-FS structures supporting extended attributes. Do not
* start extended attributes yet.
*/
void
ulfs_extattr_uepm_init(struct ulfs_extattr_per_mount *uepm)
{
uepm->uepm_flags = 0;
uepm->uepm_lockcnt = 0;
LIST_INIT(&uepm->uepm_list);
mutex_init(&uepm->uepm_lock, MUTEX_DEFAULT, IPL_NONE);
uepm->uepm_flags |= ULFS_EXTATTR_UEPM_INITIALIZED;
}
/*
* Destroy per-FS structures supporting extended attributes. Assumes
* that EAs have already been stopped, and will panic if not.
*/
void
ulfs_extattr_uepm_destroy(struct ulfs_extattr_per_mount *uepm)
{
if (!(uepm->uepm_flags & ULFS_EXTATTR_UEPM_INITIALIZED))
panic("ulfs_extattr_uepm_destroy: not initialized");
if ((uepm->uepm_flags & ULFS_EXTATTR_UEPM_STARTED))
panic("ulfs_extattr_uepm_destroy: called while still started");
/*
* It's not clear that either order for the next two lines is
* ideal, and it should never be a problem if this is only called
* during unmount, and with vfs_busy().
*/
uepm->uepm_flags &= ~ULFS_EXTATTR_UEPM_INITIALIZED;
mutex_destroy(&uepm->uepm_lock);
}
/*
* Start extended attribute support on an FS.
*/
int
ulfs_extattr_start(struct mount *mp, struct lwp *l)
{
struct ulfsmount *ump;
int error = 0;
ump = VFSTOULFS(mp);
ulfs_extattr_uepm_lock(ump);
if (!(ump->um_extattr.uepm_flags & ULFS_EXTATTR_UEPM_INITIALIZED)) {
error = EOPNOTSUPP;
goto unlock;
}
if (ump->um_extattr.uepm_flags & ULFS_EXTATTR_UEPM_STARTED) {
error = EBUSY;
goto unlock;
}
ump->um_extattr.uepm_flags |= ULFS_EXTATTR_UEPM_STARTED;
ump->um_extattr.uepm_ucred = l->l_cred;
kauth_cred_hold(ump->um_extattr.uepm_ucred);
unlock:
ulfs_extattr_uepm_unlock(ump);
return (error);
}
/*
* Helper routine: given a locked parent directory and filename, return
* the locked vnode of the inode associated with the name. Will not
* follow symlinks, may return any type of vnode. Lock on parent will
* be released even in the event of a failure. In the event that the
* target is the parent (i.e., "."), there will be two references and
* one lock, requiring the caller to possibly special-case.
*/
static int
ulfs_extattr_lookup(struct vnode *start_dvp, int lockparent, const char *dirname,
struct vnode **vp, struct lwp *l)
{
struct vop_lookup_args vargs;
struct componentname cnp;
struct vnode *target_vp;
char *pnbuf;
int error;
KASSERT(VOP_ISLOCKED(start_dvp) == LK_EXCLUSIVE);
pnbuf = PNBUF_GET();
memset(&cnp, 0, sizeof(cnp));
cnp.cn_nameiop = LOOKUP;
cnp.cn_flags = ISLASTCN | lockparent;
cnp.cn_cred = l->l_cred;
cnp.cn_nameptr = pnbuf;
error = copystr(dirname, pnbuf, MAXPATHLEN, &cnp.cn_namelen);
if (error) {
if (lockparent == 0) {
VOP_UNLOCK(start_dvp);
}
PNBUF_PUT(pnbuf);
printf("ulfs_extattr_lookup: copystr failed\n");
return (error);
}
cnp.cn_namelen--; /* trim nul termination */
vargs.a_desc = NULL;
vargs.a_dvp = start_dvp;
vargs.a_vpp = &target_vp;
vargs.a_cnp = &cnp;
error = ulfs_lookup(&vargs);
PNBUF_PUT(pnbuf);
if (error) {
if (lockparent == 0) {
VOP_UNLOCK(start_dvp);
}
return (error);
}
#if 0
if (target_vp == start_dvp)
panic("ulfs_extattr_lookup: target_vp == start_dvp");
#endif
if ((target_vp != start_dvp) && (lockparent == 0))
VOP_UNLOCK(start_dvp);
KASSERT(VOP_ISLOCKED(target_vp) == LK_EXCLUSIVE);
*vp = target_vp;
return (0);
}
/*
* Enable an EA using the passed filesystem, backing vnode, attribute name,
* namespace, and proc. Will perform a VOP_OPEN() on the vp, so expects vp
* to be locked when passed in. The vnode will be returned unlocked,
* regardless of success/failure of the function. As a result, the caller
* will always need to vrele(), but not vput().
*/
static int
ulfs_extattr_enable_with_open(struct ulfsmount *ump, struct vnode *vp,
int attrnamespace, const char *attrname, struct lwp *l)
{
int error;
error = VOP_OPEN(vp, FREAD|FWRITE, l->l_cred);
if (error) {
printf("ulfs_extattr_enable_with_open.VOP_OPEN(): failed "
"with %d\n", error);
VOP_UNLOCK(vp);
return (error);
}
mutex_enter(vp->v_interlock);
vp->v_writecount++;
mutex_exit(vp->v_interlock);
vref(vp);
VOP_UNLOCK(vp);
error = ulfs_extattr_enable(ump, attrnamespace, attrname, vp, l);
if (error != 0)
vn_close(vp, FREAD|FWRITE, l->l_cred);
return (error);
}
/*
* Given a locked directory vnode, iterate over the names in the directory
* and use ulfs_extattr_lookup() to retrieve locked vnodes of potential
* attribute files. Then invoke ulfs_extattr_enable_with_open() on each
* to attempt to start the attribute. Leaves the directory locked on
* exit.
*/
static int
ulfs_extattr_iterate_directory(struct ulfsmount *ump, struct vnode *dvp,
int attrnamespace, struct lwp *l)
{
struct vop_readdir_args vargs;
struct statvfs *sbp = &ump->um_mountp->mnt_stat;
struct dirent *dp, *edp;
struct vnode *attr_vp;
struct uio auio;
struct iovec aiov;
char *dirbuf;
int error, eofflag = 0;
if (dvp->v_type != VDIR)
return (ENOTDIR);
dirbuf = kmem_alloc(LFS_DIRBLKSIZ, KM_SLEEP);
auio.uio_iov = &aiov;
auio.uio_iovcnt = 1;
auio.uio_rw = UIO_READ;
auio.uio_offset = 0;
UIO_SETUP_SYSSPACE(&auio);
vargs.a_desc = NULL;
vargs.a_vp = dvp;
vargs.a_uio = &auio;
vargs.a_cred = l->l_cred;
vargs.a_eofflag = &eofflag;
vargs.a_ncookies = NULL;
vargs.a_cookies = NULL;
while (!eofflag) {
auio.uio_resid = LFS_DIRBLKSIZ;
aiov.iov_base = dirbuf;
aiov.iov_len = LFS_DIRBLKSIZ;
error = ulfs_readdir(&vargs);
if (error) {
printf("ulfs_extattr_iterate_directory: ulfs_readdir "
"%d\n", error);
return (error);
}
/*
* XXXRW: While in LFS, we always get LFS_DIRBLKSIZ returns from
* the directory code on success, on other file systems this
* may not be the case. For portability, we should check the
* read length on return from ulfs_readdir().
*/
edp = (struct dirent *)&dirbuf[LFS_DIRBLKSIZ];
for (dp = (struct dirent *)dirbuf; dp < edp; ) {
if (dp->d_reclen == 0)
break;
/* Skip "." and ".." */
if (dp->d_name[0] == '.' &&
(dp->d_name[1] == '\0' ||
(dp->d_name[1] == '.' && dp->d_name[2] == '\0')))
goto next;
error = ulfs_extattr_lookup(dvp, LOCKPARENT,
dp->d_name, &attr_vp, l);
if (error == ENOENT) {
goto next; /* keep silent */
} else if (error) {
printf("ulfs_extattr_iterate_directory: lookup "
"%s %d\n", dp->d_name, error);
} else if (attr_vp == dvp) {
vrele(attr_vp);
} else if (attr_vp->v_type != VREG) {
vput(attr_vp);
} else {
error = ulfs_extattr_enable_with_open(ump,
attr_vp, attrnamespace, dp->d_name, l);
vrele(attr_vp);
if (error) {
printf("ulfs_extattr_iterate_directory: "
"enable %s %d\n", dp->d_name,
error);
} else if (bootverbose) {
printf("%s: EA %s loaded\n",
sbp->f_mntonname, dp->d_name);
}
}
next:
dp = (struct dirent *) ((char *)dp + dp->d_reclen);
if (dp >= edp)
break;
}
}
kmem_free(dirbuf, LFS_DIRBLKSIZ);
return (0);
}
/*
* Auto-start of extended attributes, to be executed (optionally) at
* mount-time.
*/
int
ulfs_extattr_autostart(struct mount *mp, struct lwp *l)
{
struct vnode *rvp, *attr_dvp, *attr_system_dvp, *attr_user_dvp;
int error;
/*
* Does ULFS_EXTATTR_FSROOTSUBDIR exist off the filesystem root?
* If so, automatically start EA's.
*/
error = VFS_ROOT(mp, &rvp);
if (error) {
printf("ulfs_extattr_autostart.VFS_ROOT() returned %d\n",
error);
return (error);
}
KASSERT(VOP_ISLOCKED(rvp) == LK_EXCLUSIVE);
error = ulfs_extattr_lookup(rvp, 0,
ULFS_EXTATTR_FSROOTSUBDIR, &attr_dvp, l);
if (error) {
/* rvp ref'd but now unlocked */
KASSERT(VOP_ISLOCKED(rvp) == 0);
vrele(rvp);
return (error);
}
if (rvp == attr_dvp) {
/* Should never happen. */
KASSERT(VOP_ISLOCKED(rvp) == LK_EXCLUSIVE);
vrele(attr_dvp);
vput(rvp);
return (EINVAL);
}
KASSERT(VOP_ISLOCKED(rvp) == 0);
vrele(rvp);
KASSERT(VOP_ISLOCKED(attr_dvp) == LK_EXCLUSIVE);
if (attr_dvp->v_type != VDIR) {
printf("ulfs_extattr_autostart: %s != VDIR\n",
ULFS_EXTATTR_FSROOTSUBDIR);
goto return_vput_attr_dvp;
}
error = ulfs_extattr_start(mp, l);
if (error) {
printf("ulfs_extattr_autostart: ulfs_extattr_start failed (%d)\n",
error);
goto return_vput_attr_dvp;
}
/*
* Look for two subdirectories: ULFS_EXTATTR_SUBDIR_SYSTEM,
* ULFS_EXTATTR_SUBDIR_USER. For each, iterate over the sub-directory,
* and start with appropriate type. Failures in either don't
* result in an over-all failure. attr_dvp is left locked to
* be cleaned up on exit.
*/
error = ulfs_extattr_lookup(attr_dvp, LOCKPARENT,
ULFS_EXTATTR_SUBDIR_SYSTEM, &attr_system_dvp, l);
KASSERT(VOP_ISLOCKED(attr_dvp) == LK_EXCLUSIVE);
if (error == 0) {
KASSERT(VOP_ISLOCKED(attr_system_dvp) == LK_EXCLUSIVE);
error = ulfs_extattr_iterate_directory(VFSTOULFS(mp),
attr_system_dvp, EXTATTR_NAMESPACE_SYSTEM, l);
if (error)
printf("ulfs_extattr_iterate_directory returned %d\n",
error);
KASSERT(VOP_ISLOCKED(attr_system_dvp) == LK_EXCLUSIVE);
vput(attr_system_dvp);
}
error = ulfs_extattr_lookup(attr_dvp, LOCKPARENT,
ULFS_EXTATTR_SUBDIR_USER, &attr_user_dvp, l);
KASSERT(VOP_ISLOCKED(attr_dvp) == LK_EXCLUSIVE);
if (error == 0) {
KASSERT(VOP_ISLOCKED(attr_user_dvp) == LK_EXCLUSIVE);
error = ulfs_extattr_iterate_directory(VFSTOULFS(mp),
attr_user_dvp, EXTATTR_NAMESPACE_USER, l);
if (error)
printf("ulfs_extattr_iterate_directory returned %d\n",
error);
KASSERT(VOP_ISLOCKED(attr_user_dvp) == LK_EXCLUSIVE);
vput(attr_user_dvp);
}
/* Mask startup failures in sub-directories. */
error = 0;
return_vput_attr_dvp:
KASSERT(VOP_ISLOCKED(attr_dvp) == LK_EXCLUSIVE);
vput(attr_dvp);
return (error);
}
/*
* Stop extended attribute support on an FS.
*/
void
ulfs_extattr_stop(struct mount *mp, struct lwp *l)
{
struct ulfs_extattr_list_entry *uele;
struct ulfsmount *ump = VFSTOULFS(mp);
ulfs_extattr_uepm_lock(ump);
/*
* If we haven't been started, no big deal. Just short-circuit
* the processing work.
*/
if (!(ump->um_extattr.uepm_flags & ULFS_EXTATTR_UEPM_STARTED)) {
goto unlock;
}
while (LIST_FIRST(&ump->um_extattr.uepm_list) != NULL) {
uele = LIST_FIRST(&ump->um_extattr.uepm_list);
ulfs_extattr_disable(ump, uele->uele_attrnamespace,
uele->uele_attrname, l);
}
ump->um_extattr.uepm_flags &= ~ULFS_EXTATTR_UEPM_STARTED;
kauth_cred_free(ump->um_extattr.uepm_ucred);
ump->um_extattr.uepm_ucred = NULL;
unlock:
ulfs_extattr_uepm_unlock(ump);
}
/*
* Enable a named attribute on the specified filesystem; provide an
* unlocked backing vnode to hold the attribute data.
*/
static int
ulfs_extattr_enable(struct ulfsmount *ump, int attrnamespace,
const char *attrname, struct vnode *backing_vnode, struct lwp *l)
{
struct ulfs_extattr_list_entry *attribute;
struct iovec aiov;
struct uio auio;
int error = 0;
if (!ulfs_extattr_valid_attrname(attrnamespace, attrname))
return (EINVAL);
if (backing_vnode->v_type != VREG)
return (EINVAL);
attribute = kmem_zalloc(sizeof(*attribute), KM_SLEEP);
if (!(ump->um_extattr.uepm_flags & ULFS_EXTATTR_UEPM_STARTED)) {
error = EOPNOTSUPP;
goto free_exit;
}
if (ulfs_extattr_find_attr(ump, attrnamespace, attrname)) {
error = EEXIST;
goto free_exit;
}
strncpy(attribute->uele_attrname, attrname,
ULFS_EXTATTR_MAXEXTATTRNAME);
attribute->uele_attrnamespace = attrnamespace;
memset(&attribute->uele_fileheader, 0,
sizeof(struct ulfs_extattr_fileheader));
attribute->uele_backing_vnode = backing_vnode;
auio.uio_iov = &aiov;
auio.uio_iovcnt = 1;
aiov.iov_base = (void *) &attribute->uele_fileheader;
aiov.iov_len = sizeof(struct ulfs_extattr_fileheader);
auio.uio_resid = sizeof(struct ulfs_extattr_fileheader);
auio.uio_offset = (off_t) 0;
auio.uio_rw = UIO_READ;
UIO_SETUP_SYSSPACE(&auio);
vn_lock(backing_vnode, LK_SHARED | LK_RETRY);
error = VOP_READ(backing_vnode, &auio, IO_NODELOCKED,
ump->um_extattr.uepm_ucred);
if (error)
goto unlock_free_exit;
if (auio.uio_resid != 0) {
printf("ulfs_extattr_enable: malformed attribute header\n");
error = EINVAL;
goto unlock_free_exit;
}
/*
* Try to determine the byte order of the attribute file.
*/
if (attribute->uele_fileheader.uef_magic != ULFS_EXTATTR_MAGIC) {
attribute->uele_flags |= UELE_F_NEEDSWAP;
attribute->uele_fileheader.uef_magic =
ulfs_rw32(attribute->uele_fileheader.uef_magic,
UELE_NEEDSWAP(attribute));
if (attribute->uele_fileheader.uef_magic != ULFS_EXTATTR_MAGIC) {
printf("ulfs_extattr_enable: invalid attribute header "
"magic\n");
error = EINVAL;
goto unlock_free_exit;
}
}
attribute->uele_fileheader.uef_version =
ulfs_rw32(attribute->uele_fileheader.uef_version,
UELE_NEEDSWAP(attribute));
attribute->uele_fileheader.uef_size =
ulfs_rw32(attribute->uele_fileheader.uef_size,
UELE_NEEDSWAP(attribute));
if (attribute->uele_fileheader.uef_version != ULFS_EXTATTR_VERSION) {
printf("ulfs_extattr_enable: incorrect attribute header "
"version\n");
error = EINVAL;
goto unlock_free_exit;
}
LIST_INSERT_HEAD(&ump->um_extattr.uepm_list, attribute,
uele_entries);
VOP_UNLOCK(backing_vnode);
return (0);
unlock_free_exit:
VOP_UNLOCK(backing_vnode);
free_exit:
kmem_free(attribute, sizeof(*attribute));
return (error);
}
/*
* Disable extended attribute support on an FS.
*/
static int
ulfs_extattr_disable(struct ulfsmount *ump, int attrnamespace,
const char *attrname, struct lwp *l)
{
struct ulfs_extattr_list_entry *uele;
int error = 0;
if (!ulfs_extattr_valid_attrname(attrnamespace, attrname))
return (EINVAL);
uele = ulfs_extattr_find_attr(ump, attrnamespace, attrname);
if (!uele)
return (ENODATA);
LIST_REMOVE(uele, uele_entries);
error = vn_close(uele->uele_backing_vnode, FREAD|FWRITE,
l->l_cred);
kmem_free(uele, sizeof(*uele));
return (error);
}
/*
* VFS call to manage extended attributes in ULFS. If filename_vp is
* non-NULL, it must be passed in locked, and regardless of errors in
* processing, will be unlocked.
*/
int
ulfs_extattrctl(struct mount *mp, int cmd, struct vnode *filename_vp,
int attrnamespace, const char *attrname)
{
struct lwp *l = curlwp;
struct ulfsmount *ump = VFSTOULFS(mp);
int error;
/*
* Only privileged processes can configure extended attributes.
*/
error = kauth_authorize_system(l->l_cred, KAUTH_SYSTEM_FS_EXTATTR,
0, mp, NULL, NULL);
if (error) {
if (filename_vp != NULL)
VOP_UNLOCK(filename_vp);
return (error);
}
switch(cmd) {
case ULFS_EXTATTR_CMD_START:
if (filename_vp != NULL) {
VOP_UNLOCK(filename_vp);
return (EINVAL);
}
if (attrname != NULL)
return (EINVAL);
error = ulfs_extattr_autostart(mp, l);
return (error);
case ULFS_EXTATTR_CMD_STOP:
if (filename_vp != NULL) {
VOP_UNLOCK(filename_vp);
return (EINVAL);
}
if (attrname != NULL)
return (EINVAL);
ulfs_extattr_stop(mp, l);
return (0);
case ULFS_EXTATTR_CMD_ENABLE:
if (filename_vp == NULL)
return (EINVAL);
if (attrname == NULL) {
VOP_UNLOCK(filename_vp);
return (EINVAL);
}
/*
* ulfs_extattr_enable_with_open() will always unlock the
* vnode, regardless of failure.
*/
ulfs_extattr_uepm_lock(ump);
error = ulfs_extattr_enable_with_open(ump, filename_vp,
attrnamespace, attrname, l);
ulfs_extattr_uepm_unlock(ump);
return (error);
case ULFS_EXTATTR_CMD_DISABLE:
if (filename_vp != NULL) {
VOP_UNLOCK(filename_vp);
return (EINVAL);
}
if (attrname == NULL)
return (EINVAL);
ulfs_extattr_uepm_lock(ump);
error = ulfs_extattr_disable(ump, attrnamespace, attrname, l);
ulfs_extattr_uepm_unlock(ump);
return (error);
default:
return (EINVAL);
}
}
/*
* Read extended attribute header for a given vnode and attribute.
* Backing vnode should be locked and unlocked by caller.
*/
static int
ulfs_extattr_get_header(struct vnode *vp, struct ulfs_extattr_list_entry *uele,
struct ulfs_extattr_header *ueh, off_t *bap)
{
struct mount *mp = vp->v_mount;
struct ulfsmount *ump = VFSTOULFS(mp);
struct inode *ip = VTOI(vp);
off_t base_offset;
struct iovec aiov;
struct uio aio;
int error;
/*
* Find base offset of header in file based on file header size, and
* data header size + maximum data size, indexed by inode number.
*/
base_offset = sizeof(struct ulfs_extattr_fileheader) +
ip->i_number * (sizeof(struct ulfs_extattr_header) +
uele->uele_fileheader.uef_size);
/*
* Read in the data header to see if the data is defined, and if so
* how much.
*/
memset(ueh, 0, sizeof(struct ulfs_extattr_header));
aiov.iov_base = ueh;
aiov.iov_len = sizeof(struct ulfs_extattr_header);
aio.uio_iov = &aiov;
aio.uio_iovcnt = 1;
aio.uio_rw = UIO_READ;
aio.uio_offset = base_offset;
aio.uio_resid = sizeof(struct ulfs_extattr_header);
UIO_SETUP_SYSSPACE(&aio);
error = VOP_READ(uele->uele_backing_vnode, &aio,
IO_NODELOCKED, ump->um_extattr.uepm_ucred);
if (error)
return error;
/*
* Attribute headers are kept in file system byte order.
* XXX What about the blob of data?
*/
ueh->ueh_flags = ulfs_rw32(ueh->ueh_flags, UELE_NEEDSWAP(uele));
ueh->ueh_len = ulfs_rw32(ueh->ueh_len, UELE_NEEDSWAP(uele));
ueh->ueh_i_gen = ulfs_rw32(ueh->ueh_i_gen, UELE_NEEDSWAP(uele));
/* Defined? */
if ((ueh->ueh_flags & ULFS_EXTATTR_ATTR_FLAG_INUSE) == 0)
return ENODATA;
/* Valid for the current inode generation? */
if (ueh->ueh_i_gen != ip->i_gen) {
/*
* The inode itself has a different generation number
* than the uele data. For now, the best solution
* is to coerce this to undefined, and let it get cleaned
* up by the next write or extattrctl clean.
*/
printf("%s (%s): inode gen inconsistency (%u, %jd)\n",
__func__, mp->mnt_stat.f_mntonname, ueh->ueh_i_gen,
(intmax_t)ip->i_gen);
return ENODATA;
}
/* Local size consistency check. */
if (ueh->ueh_len > uele->uele_fileheader.uef_size)
return ENXIO;
/* Return base offset */
if (bap != NULL)
*bap = base_offset;
return 0;
}
/*
* Vnode operation to retrieve a named extended attribute.
*/
int
ulfs_getextattr(struct vop_getextattr_args *ap)
/*
vop_getextattr {
IN struct vnode *a_vp;
IN int a_attrnamespace;
IN const char *a_name;
INOUT struct uio *a_uio;
OUT size_t *a_size;
IN kauth_cred_t a_cred;
};
*/
{
struct mount *mp = ap->a_vp->v_mount;
struct ulfsmount *ump = VFSTOULFS(mp);
int error;
ulfs_extattr_uepm_lock(ump);
error = ulfs_extattr_get(ap->a_vp, ap->a_attrnamespace, ap->a_name,
ap->a_uio, ap->a_size, ap->a_cred, curlwp);
ulfs_extattr_uepm_unlock(ump);
return (error);
}
/*
* Real work associated with retrieving a named attribute--assumes that
* the attribute lock has already been grabbed.
*/
static int
ulfs_extattr_get(struct vnode *vp, int attrnamespace, const char *name,
struct uio *uio, size_t *size, kauth_cred_t cred, struct lwp *l)
{
struct ulfs_extattr_list_entry *attribute;
struct ulfs_extattr_header ueh;
struct mount *mp = vp->v_mount;
struct ulfsmount *ump = VFSTOULFS(mp);
off_t base_offset;
size_t len, old_len;
int error = 0;
if (!(ump->um_extattr.uepm_flags & ULFS_EXTATTR_UEPM_STARTED))
return (EOPNOTSUPP);
if (strlen(name) == 0)
return (EINVAL);
error = internal_extattr_check_cred(vp, attrnamespace, name, cred,
VREAD);
if (error)
return (error);
attribute = ulfs_extattr_find_attr(ump, attrnamespace, name);
if (!attribute)
return (ENODATA);
/*
* Allow only offsets of zero to encourage the read/replace
* extended attribute semantic. Otherwise we can't guarantee
* atomicity, as we don't provide locks for extended attributes.
*/
if (uio != NULL && uio->uio_offset != 0)
return (ENXIO);
/*
* Don't need to get a lock on the backing file if the getattr is
* being applied to the backing file, as the lock is already held.
*/
if (attribute->uele_backing_vnode != vp)
vn_lock(attribute->uele_backing_vnode, LK_SHARED | LK_RETRY);
error = ulfs_extattr_get_header(vp, attribute, &ueh, &base_offset);
if (error)
goto vopunlock_exit;
/* Return full data size if caller requested it. */
if (size != NULL)
*size = ueh.ueh_len;
/* Return data if the caller requested it. */
if (uio != NULL) {
/* Allow for offset into the attribute data. */
uio->uio_offset = base_offset + sizeof(struct
ulfs_extattr_header);
/*
* Figure out maximum to transfer -- use buffer size and
* local data limit.
*/
len = MIN(uio->uio_resid, ueh.ueh_len);
old_len = uio->uio_resid;
uio->uio_resid = len;
error = VOP_READ(attribute->uele_backing_vnode, uio,
IO_NODELOCKED, ump->um_extattr.uepm_ucred);
if (error)
goto vopunlock_exit;
uio->uio_resid = old_len - (len - uio->uio_resid);
}
vopunlock_exit:
if (uio != NULL)
uio->uio_offset = 0;
if (attribute->uele_backing_vnode != vp)
VOP_UNLOCK(attribute->uele_backing_vnode);
return (error);
}
/*
* Vnode operation to list extended attribute for a vnode
*/
int
ulfs_listextattr(struct vop_listextattr_args *ap)
/*
vop_listextattr {
IN struct vnode *a_vp;
IN int a_attrnamespace;
INOUT struct uio *a_uio;
OUT size_t *a_size;
IN int flag;
IN kauth_cred_t a_cred;
struct proc *a_p;
};
*/
{
struct mount *mp = ap->a_vp->v_mount;
struct ulfsmount *ump = VFSTOULFS(mp);
int error;
ulfs_extattr_uepm_lock(ump);
error = ulfs_extattr_list(ap->a_vp, ap->a_attrnamespace,
ap->a_uio, ap->a_size, ap->a_flag, ap->a_cred, curlwp);
ulfs_extattr_uepm_unlock(ump);
return (error);
}
/*
* Real work associated with retrieving list of attributes--assumes that
* the attribute lock has already been grabbed.
*/
static int
ulfs_extattr_list(struct vnode *vp, int attrnamespace,
struct uio *uio, size_t *size, int flag,
kauth_cred_t cred, struct lwp *l)
{
struct ulfs_extattr_list_entry *uele;
struct ulfs_extattr_header ueh;
struct mount *mp = vp->v_mount;
struct ulfsmount *ump = VFSTOULFS(mp);
size_t listsize = 0;
int error = 0;
if (!(ump->um_extattr.uepm_flags & ULFS_EXTATTR_UEPM_STARTED))
return (EOPNOTSUPP);
/*
* XXX: We can move this inside the loop and iterate on individual
* attributes.
*/
error = internal_extattr_check_cred(vp, attrnamespace, "", cred,
VREAD);
if (error)
return (error);
LIST_FOREACH(uele, &ump->um_extattr.uepm_list, uele_entries) {
unsigned char attrnamelen;
if (uele->uele_attrnamespace != attrnamespace)
continue;
error = ulfs_extattr_get_header(vp, uele, &ueh, NULL);
if (error == ENODATA)
continue;
if (error != 0)
return error;
/*
* Don't need to get a lock on the backing file if
* the listattr is being applied to the backing file,
* as the lock is already held.
*/
if (uele->uele_backing_vnode != vp)
vn_lock(uele->uele_backing_vnode, LK_SHARED | LK_RETRY);
/*
* +1 for trailing NUL (listxattr flavor)
* or leading name length (extattr_list_file flavor)
*/
attrnamelen = strlen(uele->uele_attrname);
listsize += attrnamelen + 1;
/* Return data if the caller requested it. */
if (uio != NULL) {
/*
* We support two flavors. Either NUL-terminated
* strings (a la listxattr), or non NUL-terminated,
* one byte length prefixed strings (for
* extattr_list_file). EXTATTR_LIST_LENPREFIX switches
* that second behavior.
*/
if (flag & EXTATTR_LIST_LENPREFIX) {
uint8_t len = (uint8_t)attrnamelen;
/* Copy leading name length */
error = uiomove(&len, sizeof(len), uio);
if (error != 0)
break;
} else {
/* Include trailing NULL */
attrnamelen++;
}
error = uiomove(uele->uele_attrname,
(size_t)attrnamelen, uio);
if (error != 0)
break;
}
if (uele->uele_backing_vnode != vp)
VOP_UNLOCK(uele->uele_backing_vnode);
if (error != 0)
return error;
}
if (uio != NULL)
uio->uio_offset = 0;
/* Return full data size if caller requested it. */
if (size != NULL)
*size = listsize;
return 0;
}
/*
* Vnode operation to remove a named attribute.
*/
int
ulfs_deleteextattr(struct vop_deleteextattr_args *ap)
/*
vop_deleteextattr {
IN struct vnode *a_vp;
IN int a_attrnamespace;
IN const char *a_name;
IN kauth_cred_t a_cred;
};
*/
{
struct mount *mp = ap->a_vp->v_mount;
struct ulfsmount *ump = VFSTOULFS(mp);
int error;
ulfs_extattr_uepm_lock(ump);
error = ulfs_extattr_rm(ap->a_vp, ap->a_attrnamespace, ap->a_name,
ap->a_cred, curlwp);
ulfs_extattr_uepm_unlock(ump);
return (error);
}
/*
* Vnode operation to set a named attribute.
*/
int
ulfs_setextattr(struct vop_setextattr_args *ap)
/*
vop_setextattr {
IN struct vnode *a_vp;
IN int a_attrnamespace;
IN const char *a_name;
INOUT struct uio *a_uio;
IN kauth_cred_t a_cred;
};
*/
{
struct mount *mp = ap->a_vp->v_mount;
struct ulfsmount *ump = VFSTOULFS(mp);
int error;
ulfs_extattr_uepm_lock(ump);
/*
* XXX: No longer a supported way to delete extended attributes.
*/
if (ap->a_uio == NULL) {
ulfs_extattr_uepm_unlock(ump);
return (EINVAL);
}
error = ulfs_extattr_set(ap->a_vp, ap->a_attrnamespace, ap->a_name,
ap->a_uio, ap->a_cred, curlwp);
ulfs_extattr_uepm_unlock(ump);
return (error);
}
/*
* Real work associated with setting a vnode's extended attributes;
* assumes that the attribute lock has already been grabbed.
*/
static int
ulfs_extattr_set(struct vnode *vp, int attrnamespace, const char *name,
struct uio *uio, kauth_cred_t cred, struct lwp *l)
{
struct ulfs_extattr_list_entry *attribute;
struct ulfs_extattr_header ueh;
struct iovec local_aiov;
struct uio local_aio;
struct mount *mp = vp->v_mount;
struct ulfsmount *ump = VFSTOULFS(mp);
struct inode *ip = VTOI(vp);
off_t base_offset;
int error = 0, ioflag;
if (vp->v_mount->mnt_flag & MNT_RDONLY)
return (EROFS);
if (!(ump->um_extattr.uepm_flags & ULFS_EXTATTR_UEPM_STARTED))
return (EOPNOTSUPP);
if (!ulfs_extattr_valid_attrname(attrnamespace, name))
return (EINVAL);
error = internal_extattr_check_cred(vp, attrnamespace, name, cred,
VWRITE);
if (error)
return (error);
attribute = ulfs_extattr_find_attr(ump, attrnamespace, name);
if (!attribute) {
attribute = ulfs_extattr_autocreate_attr(vp, attrnamespace,
name, l);
if (!attribute)
return (ENODATA);
}
/*
* Early rejection of invalid offsets/length.
* Reject: any offset but 0 (replace)
* Any size greater than attribute size limit
*/
if (uio->uio_offset != 0 ||
uio->uio_resid > attribute->uele_fileheader.uef_size)
return (ENXIO);
/*
* Find base offset of header in file based on file header size, and
* data header size + maximum data size, indexed by inode number.
*/
base_offset = sizeof(struct ulfs_extattr_fileheader) +
ip->i_number * (sizeof(struct ulfs_extattr_header) +
attribute->uele_fileheader.uef_size);
/*
* Write out a data header for the data.
*/
ueh.ueh_len = ulfs_rw32((uint32_t) uio->uio_resid,
UELE_NEEDSWAP(attribute));
ueh.ueh_flags = ulfs_rw32(ULFS_EXTATTR_ATTR_FLAG_INUSE,
UELE_NEEDSWAP(attribute));
ueh.ueh_i_gen = ulfs_rw32(ip->i_gen, UELE_NEEDSWAP(attribute));
local_aiov.iov_base = &ueh;
local_aiov.iov_len = sizeof(struct ulfs_extattr_header);
local_aio.uio_iov = &local_aiov;
local_aio.uio_iovcnt = 1;
local_aio.uio_rw = UIO_WRITE;
local_aio.uio_offset = base_offset;
local_aio.uio_resid = sizeof(struct ulfs_extattr_header);
UIO_SETUP_SYSSPACE(&local_aio);
/*
* Don't need to get a lock on the backing file if the setattr is
* being applied to the backing file, as the lock is already held.
*/
if (attribute->uele_backing_vnode != vp)
vn_lock(attribute->uele_backing_vnode,
LK_EXCLUSIVE | LK_RETRY);
ioflag = IO_NODELOCKED;
if (ulfs_extattr_sync)
ioflag |= IO_SYNC;
error = VOP_WRITE(attribute->uele_backing_vnode, &local_aio, ioflag,
ump->um_extattr.uepm_ucred);
if (error)
goto vopunlock_exit;
if (local_aio.uio_resid != 0) {
error = ENXIO;
goto vopunlock_exit;
}
/*
* Write out user data.
* XXX NOT ATOMIC WITH RESPECT TO THE HEADER.
*/
uio->uio_offset = base_offset + sizeof(struct ulfs_extattr_header);
ioflag = IO_NODELOCKED;
if (ulfs_extattr_sync)
ioflag |= IO_SYNC;
error = VOP_WRITE(attribute->uele_backing_vnode, uio, ioflag,
ump->um_extattr.uepm_ucred);
vopunlock_exit:
uio->uio_offset = 0;
if (attribute->uele_backing_vnode != vp)
VOP_UNLOCK(attribute->uele_backing_vnode);
return (error);
}
/*
* Real work associated with removing an extended attribute from a vnode.
* Assumes the attribute lock has already been grabbed.
*/
static int
ulfs_extattr_rm(struct vnode *vp, int attrnamespace, const char *name,
kauth_cred_t cred, struct lwp *l)
{
struct ulfs_extattr_list_entry *attribute;
struct ulfs_extattr_header ueh;
struct mount *mp = vp->v_mount;
struct ulfsmount *ump = VFSTOULFS(mp);
struct iovec local_aiov;
struct uio local_aio;
off_t base_offset;
int error = 0, ioflag;
if (vp->v_mount->mnt_flag & MNT_RDONLY)
return (EROFS);
if (!(ump->um_extattr.uepm_flags & ULFS_EXTATTR_UEPM_STARTED))
return (EOPNOTSUPP);
if (!ulfs_extattr_valid_attrname(attrnamespace, name))
return (EINVAL);
error = internal_extattr_check_cred(vp, attrnamespace, name, cred,
VWRITE);
if (error)
return (error);
attribute = ulfs_extattr_find_attr(ump, attrnamespace, name);
if (!attribute)
return (ENODATA);
/*
* Don't need to get a lock on the backing file if the getattr is
* being applied to the backing file, as the lock is already held.
*/
if (attribute->uele_backing_vnode != vp)
vn_lock(attribute->uele_backing_vnode, LK_EXCLUSIVE | LK_RETRY);
error = ulfs_extattr_get_header(vp, attribute, &ueh, &base_offset);
if (error)
goto vopunlock_exit;
/* Flag it as not in use. */
ueh.ueh_flags = 0; /* No need to byte swap 0 */
ueh.ueh_len = 0; /* ...ditto... */
local_aiov.iov_base = &ueh;
local_aiov.iov_len = sizeof(struct ulfs_extattr_header);
local_aio.uio_iov = &local_aiov;
local_aio.uio_iovcnt = 1;
local_aio.uio_rw = UIO_WRITE;
local_aio.uio_offset = base_offset;
local_aio.uio_resid = sizeof(struct ulfs_extattr_header);
UIO_SETUP_SYSSPACE(&local_aio);
ioflag = IO_NODELOCKED;
if (ulfs_extattr_sync)
ioflag |= IO_SYNC;
error = VOP_WRITE(attribute->uele_backing_vnode, &local_aio, ioflag,
ump->um_extattr.uepm_ucred);
if (error)
goto vopunlock_exit;
if (local_aio.uio_resid != 0)
error = ENXIO;
vopunlock_exit:
VOP_UNLOCK(attribute->uele_backing_vnode);
return (error);
}
/*
* Called by ULFS when an inode is no longer active and should have its
* attributes stripped.
*/
void
ulfs_extattr_vnode_inactive(struct vnode *vp, struct lwp *l)
{
struct ulfs_extattr_list_entry *uele;
struct mount *mp = vp->v_mount;
struct ulfsmount *ump = VFSTOULFS(mp);
/*
* In that case, we cannot lock. We should not have any active vnodes
* on the fs if this is not yet initialized but is going to be, so
* this can go unlocked.
*/
if (!(ump->um_extattr.uepm_flags & ULFS_EXTATTR_UEPM_INITIALIZED))
return;
ulfs_extattr_uepm_lock(ump);
if (!(ump->um_extattr.uepm_flags & ULFS_EXTATTR_UEPM_STARTED)) {
ulfs_extattr_uepm_unlock(ump);
return;
}
LIST_FOREACH(uele, &ump->um_extattr.uepm_list, uele_entries)
ulfs_extattr_rm(vp, uele->uele_attrnamespace,
uele->uele_attrname, lwp0.l_cred, l);
ulfs_extattr_uepm_unlock(ump);
}
void
ulfs_extattr_init(void)
{
}
void
ulfs_extattr_done(void)
{
}
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