zfs-builds-mm/zfs-2.0.0/module/os/freebsd/zfs/zfs_dir.c

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2020-12-02 17:25:31 +01:00
/*
* 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) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
* Copyright (c) 2013, 2016 by Delphix. All rights reserved.
* Copyright 2017 Nexenta Systems, Inc.
*/
#include <sys/types.h>
#include <sys/param.h>
#include <sys/time.h>
#include <sys/systm.h>
#include <sys/sysmacros.h>
#include <sys/resource.h>
#include <sys/vfs.h>
#include <sys/vnode.h>
#include <sys/extdirent.h>
#include <sys/file.h>
#include <sys/kmem.h>
#include <sys/uio.h>
#include <sys/cmn_err.h>
#include <sys/errno.h>
#include <sys/stat.h>
#include <sys/unistd.h>
#include <sys/sunddi.h>
#include <sys/random.h>
#include <sys/policy.h>
#include <sys/condvar.h>
#include <sys/callb.h>
#include <sys/smp.h>
#include <sys/zfs_dir.h>
#include <sys/zfs_acl.h>
#include <sys/fs/zfs.h>
#include <sys/zap.h>
#include <sys/dmu.h>
#include <sys/atomic.h>
#include <sys/zfs_ctldir.h>
#include <sys/zfs_fuid.h>
#include <sys/sa.h>
#include <sys/zfs_sa.h>
#include <sys/dmu_objset.h>
#include <sys/dsl_dir.h>
#include <sys/ccompat.h>
/*
* zfs_match_find() is used by zfs_dirent_lookup() to perform zap lookups
* of names after deciding which is the appropriate lookup interface.
*/
static int
zfs_match_find(zfsvfs_t *zfsvfs, znode_t *dzp, const char *name,
matchtype_t mt, uint64_t *zoid)
{
int error;
if (zfsvfs->z_norm) {
/*
* In the non-mixed case we only expect there would ever
* be one match, but we need to use the normalizing lookup.
*/
error = zap_lookup_norm(zfsvfs->z_os, dzp->z_id, name, 8, 1,
zoid, mt, NULL, 0, NULL);
} else {
error = zap_lookup(zfsvfs->z_os, dzp->z_id, name, 8, 1, zoid);
}
*zoid = ZFS_DIRENT_OBJ(*zoid);
return (error);
}
/*
* Look up a directory entry under a locked vnode.
* dvp being locked gives us a guarantee that there are no concurrent
* modification of the directory and, thus, if a node can be found in
* the directory, then it must not be unlinked.
*
* Input arguments:
* dzp - znode for directory
* name - name of entry to lock
* flag - ZNEW: if the entry already exists, fail with EEXIST.
* ZEXISTS: if the entry does not exist, fail with ENOENT.
* ZXATTR: we want dzp's xattr directory
*
* Output arguments:
* zpp - pointer to the znode for the entry (NULL if there isn't one)
*
* Return value: 0 on success or errno on failure.
*
* NOTE: Always checks for, and rejects, '.' and '..'.
*/
int
zfs_dirent_lookup(znode_t *dzp, const char *name, znode_t **zpp, int flag)
{
zfsvfs_t *zfsvfs = dzp->z_zfsvfs;
znode_t *zp;
matchtype_t mt = 0;
uint64_t zoid;
int error = 0;
if (zfsvfs->z_replay == B_FALSE)
ASSERT_VOP_LOCKED(ZTOV(dzp), __func__);
*zpp = NULL;
/*
* Verify that we are not trying to lock '.', '..', or '.zfs'
*/
if (name[0] == '.' &&
(((name[1] == '\0') || (name[1] == '.' && name[2] == '\0')) ||
(zfs_has_ctldir(dzp) && strcmp(name, ZFS_CTLDIR_NAME) == 0)))
return (SET_ERROR(EEXIST));
/*
* Case sensitivity and normalization preferences are set when
* the file system is created. These are stored in the
* zfsvfs->z_case and zfsvfs->z_norm fields. These choices
* affect how we perform zap lookups.
*
* When matching we may need to normalize & change case according to
* FS settings.
*
* Note that a normalized match is necessary for a case insensitive
* filesystem when the lookup request is not exact because normalization
* can fold case independent of normalizing code point sequences.
*
* See the table above zfs_dropname().
*/
if (zfsvfs->z_norm != 0) {
mt = MT_NORMALIZE;
/*
* Determine if the match needs to honor the case specified in
* lookup, and if so keep track of that so that during
* normalization we don't fold case.
*/
if (zfsvfs->z_case == ZFS_CASE_MIXED) {
mt |= MT_MATCH_CASE;
}
}
/*
* Only look in or update the DNLC if we are looking for the
* name on a file system that does not require normalization
* or case folding. We can also look there if we happen to be
* on a non-normalizing, mixed sensitivity file system IF we
* are looking for the exact name.
*
* NB: we do not need to worry about this flag for ZFS_CASE_SENSITIVE
* because in that case MT_EXACT and MT_FIRST should produce exactly
* the same result.
*/
if (dzp->z_unlinked && !(flag & ZXATTR))
return (ENOENT);
if (flag & ZXATTR) {
error = sa_lookup(dzp->z_sa_hdl, SA_ZPL_XATTR(zfsvfs), &zoid,
sizeof (zoid));
if (error == 0)
error = (zoid == 0 ? ENOENT : 0);
} else {
error = zfs_match_find(zfsvfs, dzp, name, mt, &zoid);
}
if (error) {
if (error != ENOENT || (flag & ZEXISTS)) {
return (error);
}
} else {
if (flag & ZNEW) {
return (SET_ERROR(EEXIST));
}
error = zfs_zget(zfsvfs, zoid, &zp);
if (error)
return (error);
ASSERT(!zp->z_unlinked);
*zpp = zp;
}
return (0);
}
static int
zfs_dd_lookup(znode_t *dzp, znode_t **zpp)
{
zfsvfs_t *zfsvfs = dzp->z_zfsvfs;
znode_t *zp;
uint64_t parent;
int error;
if (zfsvfs->z_replay == B_FALSE)
ASSERT_VOP_LOCKED(ZTOV(dzp), __func__);
ASSERT(RRM_READ_HELD(&zfsvfs->z_teardown_lock));
if (dzp->z_unlinked)
return (ENOENT);
if ((error = sa_lookup(dzp->z_sa_hdl,
SA_ZPL_PARENT(zfsvfs), &parent, sizeof (parent))) != 0)
return (error);
error = zfs_zget(zfsvfs, parent, &zp);
if (error == 0)
*zpp = zp;
return (error);
}
int
zfs_dirlook(znode_t *dzp, const char *name, znode_t **zpp)
{
zfsvfs_t *zfsvfs __unused = dzp->z_zfsvfs;
znode_t *zp = NULL;
int error = 0;
#ifdef ZFS_DEBUG
if (zfsvfs->z_replay == B_FALSE)
ASSERT_VOP_LOCKED(ZTOV(dzp), __func__);
ASSERT(RRM_READ_HELD(&zfsvfs->z_teardown_lock));
#endif
if (dzp->z_unlinked)
return (SET_ERROR(ENOENT));
if (name[0] == 0 || (name[0] == '.' && name[1] == 0)) {
*zpp = dzp;
} else if (name[0] == '.' && name[1] == '.' && name[2] == 0) {
error = zfs_dd_lookup(dzp, &zp);
if (error == 0)
*zpp = zp;
} else {
error = zfs_dirent_lookup(dzp, name, &zp, ZEXISTS);
if (error == 0) {
dzp->z_zn_prefetch = B_TRUE; /* enable prefetching */
*zpp = zp;
}
}
return (error);
}
/*
* unlinked Set (formerly known as the "delete queue") Error Handling
*
* When dealing with the unlinked set, we dmu_tx_hold_zap(), but we
* don't specify the name of the entry that we will be manipulating. We
* also fib and say that we won't be adding any new entries to the
* unlinked set, even though we might (this is to lower the minimum file
* size that can be deleted in a full filesystem). So on the small
* chance that the nlink list is using a fat zap (ie. has more than
* 2000 entries), we *may* not pre-read a block that's needed.
* Therefore it is remotely possible for some of the assertions
* regarding the unlinked set below to fail due to i/o error. On a
* nondebug system, this will result in the space being leaked.
*/
void
zfs_unlinked_add(znode_t *zp, dmu_tx_t *tx)
{
zfsvfs_t *zfsvfs = zp->z_zfsvfs;
ASSERT(zp->z_unlinked);
ASSERT(zp->z_links == 0);
VERIFY3U(0, ==,
zap_add_int(zfsvfs->z_os, zfsvfs->z_unlinkedobj, zp->z_id, tx));
dataset_kstats_update_nunlinks_kstat(&zfsvfs->z_kstat, 1);
}
/*
* Clean up any znodes that had no links when we either crashed or
* (force) umounted the file system.
*/
void
zfs_unlinked_drain(zfsvfs_t *zfsvfs)
{
zap_cursor_t zc;
zap_attribute_t zap;
dmu_object_info_t doi;
znode_t *zp;
dmu_tx_t *tx;
int error;
/*
* Iterate over the contents of the unlinked set.
*/
for (zap_cursor_init(&zc, zfsvfs->z_os, zfsvfs->z_unlinkedobj);
zap_cursor_retrieve(&zc, &zap) == 0;
zap_cursor_advance(&zc)) {
/*
* See what kind of object we have in list
*/
error = dmu_object_info(zfsvfs->z_os,
zap.za_first_integer, &doi);
if (error != 0)
continue;
ASSERT((doi.doi_type == DMU_OT_PLAIN_FILE_CONTENTS) ||
(doi.doi_type == DMU_OT_DIRECTORY_CONTENTS));
/*
* We need to re-mark these list entries for deletion,
* so we pull them back into core and set zp->z_unlinked.
*/
error = zfs_zget(zfsvfs, zap.za_first_integer, &zp);
/*
* We may pick up znodes that are already marked for deletion.
* This could happen during the purge of an extended attribute
* directory. All we need to do is skip over them, since they
* are already in the system marked z_unlinked.
*/
if (error != 0)
continue;
vn_lock(ZTOV(zp), LK_EXCLUSIVE | LK_RETRY);
/*
* Due to changes in zfs_rmnode we need to make sure the
* link count is set to zero here.
*/
if (zp->z_links != 0) {
tx = dmu_tx_create(zfsvfs->z_os);
dmu_tx_hold_sa(tx, zp->z_sa_hdl, B_FALSE);
error = dmu_tx_assign(tx, TXG_WAIT);
if (error != 0) {
dmu_tx_abort(tx);
vput(ZTOV(zp));
continue;
}
zp->z_links = 0;
VERIFY0(sa_update(zp->z_sa_hdl, SA_ZPL_LINKS(zfsvfs),
&zp->z_links, sizeof (zp->z_links), tx));
dmu_tx_commit(tx);
}
zp->z_unlinked = B_TRUE;
vput(ZTOV(zp));
}
zap_cursor_fini(&zc);
}
/*
* Delete the entire contents of a directory. Return a count
* of the number of entries that could not be deleted. If we encounter
* an error, return a count of at least one so that the directory stays
* in the unlinked set.
*
* NOTE: this function assumes that the directory is inactive,
* so there is no need to lock its entries before deletion.
* Also, it assumes the directory contents is *only* regular
* files.
*/
static int
zfs_purgedir(znode_t *dzp)
{
zap_cursor_t zc;
zap_attribute_t zap;
znode_t *xzp;
dmu_tx_t *tx;
zfsvfs_t *zfsvfs = dzp->z_zfsvfs;
int skipped = 0;
int error;
for (zap_cursor_init(&zc, zfsvfs->z_os, dzp->z_id);
(error = zap_cursor_retrieve(&zc, &zap)) == 0;
zap_cursor_advance(&zc)) {
error = zfs_zget(zfsvfs,
ZFS_DIRENT_OBJ(zap.za_first_integer), &xzp);
if (error) {
skipped += 1;
continue;
}
vn_lock(ZTOV(xzp), LK_EXCLUSIVE | LK_RETRY);
ASSERT((ZTOV(xzp)->v_type == VREG) ||
(ZTOV(xzp)->v_type == VLNK));
tx = dmu_tx_create(zfsvfs->z_os);
dmu_tx_hold_sa(tx, dzp->z_sa_hdl, B_FALSE);
dmu_tx_hold_zap(tx, dzp->z_id, FALSE, zap.za_name);
dmu_tx_hold_sa(tx, xzp->z_sa_hdl, B_FALSE);
dmu_tx_hold_zap(tx, zfsvfs->z_unlinkedobj, FALSE, NULL);
/* Is this really needed ? */
zfs_sa_upgrade_txholds(tx, xzp);
dmu_tx_mark_netfree(tx);
error = dmu_tx_assign(tx, TXG_WAIT);
if (error) {
dmu_tx_abort(tx);
vput(ZTOV(xzp));
skipped += 1;
continue;
}
error = zfs_link_destroy(dzp, zap.za_name, xzp, tx, 0, NULL);
if (error)
skipped += 1;
dmu_tx_commit(tx);
vput(ZTOV(xzp));
}
zap_cursor_fini(&zc);
if (error != ENOENT)
skipped += 1;
return (skipped);
}
extern taskq_t *zfsvfs_taskq;
void
zfs_rmnode(znode_t *zp)
{
zfsvfs_t *zfsvfs = zp->z_zfsvfs;
objset_t *os = zfsvfs->z_os;
dmu_tx_t *tx;
uint64_t acl_obj;
uint64_t xattr_obj;
uint64_t count;
int error;
ASSERT(zp->z_links == 0);
if (zfsvfs->z_replay == B_FALSE)
ASSERT_VOP_ELOCKED(ZTOV(zp), __func__);
/*
* If this is an attribute directory, purge its contents.
*/
if (ZTOV(zp) != NULL && ZTOV(zp)->v_type == VDIR &&
(zp->z_pflags & ZFS_XATTR)) {
if (zfs_purgedir(zp) != 0) {
/*
* Not enough space to delete some xattrs.
* Leave it in the unlinked set.
*/
zfs_znode_dmu_fini(zp);
zfs_znode_free(zp);
return;
}
} else {
/*
* Free up all the data in the file. We don't do this for
* XATTR directories because we need truncate and remove to be
* in the same tx, like in zfs_znode_delete(). Otherwise, if
* we crash here we'll end up with an inconsistent truncated
* zap object in the delete queue. Note a truncated file is
* harmless since it only contains user data.
*/
error = dmu_free_long_range(os, zp->z_id, 0, DMU_OBJECT_END);
if (error) {
/*
* Not enough space or we were interrupted by unmount.
* Leave the file in the unlinked set.
*/
zfs_znode_dmu_fini(zp);
zfs_znode_free(zp);
return;
}
}
/*
* If the file has extended attributes, we're going to unlink
* the xattr dir.
*/
error = sa_lookup(zp->z_sa_hdl, SA_ZPL_XATTR(zfsvfs),
&xattr_obj, sizeof (xattr_obj));
if (error)
xattr_obj = 0;
acl_obj = zfs_external_acl(zp);
/*
* Set up the final transaction.
*/
tx = dmu_tx_create(os);
dmu_tx_hold_free(tx, zp->z_id, 0, DMU_OBJECT_END);
dmu_tx_hold_zap(tx, zfsvfs->z_unlinkedobj, FALSE, NULL);
if (xattr_obj)
dmu_tx_hold_zap(tx, zfsvfs->z_unlinkedobj, TRUE, NULL);
if (acl_obj)
dmu_tx_hold_free(tx, acl_obj, 0, DMU_OBJECT_END);
zfs_sa_upgrade_txholds(tx, zp);
error = dmu_tx_assign(tx, TXG_WAIT);
if (error) {
/*
* Not enough space to delete the file. Leave it in the
* unlinked set, leaking it until the fs is remounted (at
* which point we'll call zfs_unlinked_drain() to process it).
*/
dmu_tx_abort(tx);
zfs_znode_dmu_fini(zp);
zfs_znode_free(zp);
return;
}
/*
* FreeBSD's implementation of zfs_zget requires a vnode to back it.
* This means that we could end up calling into getnewvnode while
* calling zfs_rmnode as a result of a prior call to getnewvnode
* trying to clear vnodes out of the cache. If this repeats we can
* recurse enough that we overflow our stack. To avoid this, we
* avoid calling zfs_zget on the xattr znode and instead simply add
* it to the unlinked set and schedule a call to zfs_unlinked_drain.
*/
if (xattr_obj) {
/* Add extended attribute directory to the unlinked set. */
VERIFY3U(0, ==,
zap_add_int(os, zfsvfs->z_unlinkedobj, xattr_obj, tx));
}
mutex_enter(&os->os_dsl_dataset->ds_dir->dd_activity_lock);
/* Remove this znode from the unlinked set */
VERIFY3U(0, ==,
zap_remove_int(os, zfsvfs->z_unlinkedobj, zp->z_id, tx));
if (zap_count(os, zfsvfs->z_unlinkedobj, &count) == 0 && count == 0) {
cv_broadcast(&os->os_dsl_dataset->ds_dir->dd_activity_cv);
}
mutex_exit(&os->os_dsl_dataset->ds_dir->dd_activity_lock);
dataset_kstats_update_nunlinked_kstat(&zfsvfs->z_kstat, 1);
zfs_znode_delete(zp, tx);
dmu_tx_commit(tx);
if (xattr_obj) {
/*
* We're using the FreeBSD taskqueue API here instead of
* the Solaris taskq API since the FreeBSD API allows for a
* task to be enqueued multiple times but executed once.
*/
taskqueue_enqueue(zfsvfs_taskq->tq_queue,
&zfsvfs->z_unlinked_drain_task);
}
}
static uint64_t
zfs_dirent(znode_t *zp, uint64_t mode)
{
uint64_t de = zp->z_id;
if (zp->z_zfsvfs->z_version >= ZPL_VERSION_DIRENT_TYPE)
de |= IFTODT(mode) << 60;
return (de);
}
/*
* Link zp into dzp. Can only fail if zp has been unlinked.
*/
int
zfs_link_create(znode_t *dzp, const char *name, znode_t *zp, dmu_tx_t *tx,
int flag)
{
zfsvfs_t *zfsvfs = zp->z_zfsvfs;
vnode_t *vp = ZTOV(zp);
uint64_t value;
int zp_is_dir = (vp->v_type == VDIR);
sa_bulk_attr_t bulk[5];
uint64_t mtime[2], ctime[2];
int count = 0;
int error;
if (zfsvfs->z_replay == B_FALSE) {
ASSERT_VOP_ELOCKED(ZTOV(dzp), __func__);
ASSERT_VOP_ELOCKED(ZTOV(zp), __func__);
}
if (zp_is_dir) {
if (dzp->z_links >= ZFS_LINK_MAX)
return (SET_ERROR(EMLINK));
}
if (!(flag & ZRENAMING)) {
if (zp->z_unlinked) { /* no new links to unlinked zp */
ASSERT(!(flag & (ZNEW | ZEXISTS)));
return (SET_ERROR(ENOENT));
}
if (zp->z_links >= ZFS_LINK_MAX - zp_is_dir) {
return (SET_ERROR(EMLINK));
}
zp->z_links++;
SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_LINKS(zfsvfs), NULL,
&zp->z_links, sizeof (zp->z_links));
} else {
ASSERT(zp->z_unlinked == 0);
}
value = zfs_dirent(zp, zp->z_mode);
error = zap_add(zp->z_zfsvfs->z_os, dzp->z_id, name,
8, 1, &value, tx);
/*
* zap_add could fail to add the entry if it exceeds the capacity of the
* leaf-block and zap_leaf_split() failed to help.
* The caller of this routine is responsible for failing the transaction
* which will rollback the SA updates done above.
*/
if (error != 0) {
if (!(flag & ZRENAMING) && !(flag & ZNEW))
zp->z_links--;
return (error);
}
SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_PARENT(zfsvfs), NULL,
&dzp->z_id, sizeof (dzp->z_id));
SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_FLAGS(zfsvfs), NULL,
&zp->z_pflags, sizeof (zp->z_pflags));
if (!(flag & ZNEW)) {
SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_CTIME(zfsvfs), NULL,
ctime, sizeof (ctime));
zfs_tstamp_update_setup(zp, STATE_CHANGED, mtime,
ctime);
}
error = sa_bulk_update(zp->z_sa_hdl, bulk, count, tx);
ASSERT0(error);
dzp->z_size++;
dzp->z_links += zp_is_dir;
count = 0;
SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_SIZE(zfsvfs), NULL,
&dzp->z_size, sizeof (dzp->z_size));
SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_LINKS(zfsvfs), NULL,
&dzp->z_links, sizeof (dzp->z_links));
SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_MTIME(zfsvfs), NULL,
mtime, sizeof (mtime));
SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_CTIME(zfsvfs), NULL,
ctime, sizeof (ctime));
SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_FLAGS(zfsvfs), NULL,
&dzp->z_pflags, sizeof (dzp->z_pflags));
zfs_tstamp_update_setup(dzp, CONTENT_MODIFIED, mtime, ctime);
error = sa_bulk_update(dzp->z_sa_hdl, bulk, count, tx);
ASSERT0(error);
return (0);
}
/*
* The match type in the code for this function should conform to:
*
* ------------------------------------------------------------------------
* fs type | z_norm | lookup type | match type
* ---------|-------------|-------------|----------------------------------
* CS !norm | 0 | 0 | 0 (exact)
* CS norm | formX | 0 | MT_NORMALIZE
* CI !norm | upper | !ZCIEXACT | MT_NORMALIZE
* CI !norm | upper | ZCIEXACT | MT_NORMALIZE | MT_MATCH_CASE
* CI norm | upper|formX | !ZCIEXACT | MT_NORMALIZE
* CI norm | upper|formX | ZCIEXACT | MT_NORMALIZE | MT_MATCH_CASE
* CM !norm | upper | !ZCILOOK | MT_NORMALIZE | MT_MATCH_CASE
* CM !norm | upper | ZCILOOK | MT_NORMALIZE
* CM norm | upper|formX | !ZCILOOK | MT_NORMALIZE | MT_MATCH_CASE
* CM norm | upper|formX | ZCILOOK | MT_NORMALIZE
*
* Abbreviations:
* CS = Case Sensitive, CI = Case Insensitive, CM = Case Mixed
* upper = case folding set by fs type on creation (U8_TEXTPREP_TOUPPER)
* formX = unicode normalization form set on fs creation
*/
static int
zfs_dropname(znode_t *dzp, const char *name, znode_t *zp, dmu_tx_t *tx,
int flag)
{
int error;
if (zp->z_zfsvfs->z_norm) {
matchtype_t mt = MT_NORMALIZE;
if (zp->z_zfsvfs->z_case == ZFS_CASE_MIXED) {
mt |= MT_MATCH_CASE;
}
error = zap_remove_norm(zp->z_zfsvfs->z_os, dzp->z_id,
name, mt, tx);
} else {
error = zap_remove(zp->z_zfsvfs->z_os, dzp->z_id, name, tx);
}
return (error);
}
/*
* Unlink zp from dzp, and mark zp for deletion if this was the last link.
* Can fail if zp is a mount point (EBUSY) or a non-empty directory (EEXIST).
* If 'unlinkedp' is NULL, we put unlinked znodes on the unlinked list.
* If it's non-NULL, we use it to indicate whether the znode needs deletion,
* and it's the caller's job to do it.
*/
int
zfs_link_destroy(znode_t *dzp, const char *name, znode_t *zp, dmu_tx_t *tx,
int flag, boolean_t *unlinkedp)
{
zfsvfs_t *zfsvfs = dzp->z_zfsvfs;
vnode_t *vp = ZTOV(zp);
int zp_is_dir = (vp->v_type == VDIR);
boolean_t unlinked = B_FALSE;
sa_bulk_attr_t bulk[5];
uint64_t mtime[2], ctime[2];
int count = 0;
int error;
if (zfsvfs->z_replay == B_FALSE) {
ASSERT_VOP_ELOCKED(ZTOV(dzp), __func__);
ASSERT_VOP_ELOCKED(ZTOV(zp), __func__);
}
if (!(flag & ZRENAMING)) {
if (zp_is_dir && !zfs_dirempty(zp))
return (SET_ERROR(ENOTEMPTY));
/*
* If we get here, we are going to try to remove the object.
* First try removing the name from the directory; if that
* fails, return the error.
*/
error = zfs_dropname(dzp, name, zp, tx, flag);
if (error != 0) {
return (error);
}
if (zp->z_links <= zp_is_dir) {
zfs_panic_recover("zfs: link count on vnode %p is %u, "
"should be at least %u", zp->z_vnode,
(int)zp->z_links,
zp_is_dir + 1);
zp->z_links = zp_is_dir + 1;
}
if (--zp->z_links == zp_is_dir) {
zp->z_unlinked = B_TRUE;
zp->z_links = 0;
unlinked = B_TRUE;
} else {
SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_CTIME(zfsvfs),
NULL, &ctime, sizeof (ctime));
SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_FLAGS(zfsvfs),
NULL, &zp->z_pflags, sizeof (zp->z_pflags));
zfs_tstamp_update_setup(zp, STATE_CHANGED, mtime,
ctime);
}
SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_LINKS(zfsvfs),
NULL, &zp->z_links, sizeof (zp->z_links));
error = sa_bulk_update(zp->z_sa_hdl, bulk, count, tx);
count = 0;
ASSERT0(error);
} else {
ASSERT(zp->z_unlinked == 0);
error = zfs_dropname(dzp, name, zp, tx, flag);
if (error != 0)
return (error);
}
dzp->z_size--; /* one dirent removed */
dzp->z_links -= zp_is_dir; /* ".." link from zp */
SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_LINKS(zfsvfs),
NULL, &dzp->z_links, sizeof (dzp->z_links));
SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_SIZE(zfsvfs),
NULL, &dzp->z_size, sizeof (dzp->z_size));
SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_CTIME(zfsvfs),
NULL, ctime, sizeof (ctime));
SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_MTIME(zfsvfs),
NULL, mtime, sizeof (mtime));
SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_FLAGS(zfsvfs),
NULL, &dzp->z_pflags, sizeof (dzp->z_pflags));
zfs_tstamp_update_setup(dzp, CONTENT_MODIFIED, mtime, ctime);
error = sa_bulk_update(dzp->z_sa_hdl, bulk, count, tx);
ASSERT0(error);
if (unlinkedp != NULL)
*unlinkedp = unlinked;
else if (unlinked)
zfs_unlinked_add(zp, tx);
return (0);
}
/*
* Indicate whether the directory is empty.
*/
boolean_t
zfs_dirempty(znode_t *dzp)
{
return (dzp->z_size == 2);
}
int
zfs_make_xattrdir(znode_t *zp, vattr_t *vap, znode_t **xvpp, cred_t *cr)
{
zfsvfs_t *zfsvfs = zp->z_zfsvfs;
znode_t *xzp;
dmu_tx_t *tx;
int error;
zfs_acl_ids_t acl_ids;
boolean_t fuid_dirtied;
uint64_t parent __unused;
*xvpp = NULL;
if ((error = zfs_acl_ids_create(zp, IS_XATTR, vap, cr, NULL,
&acl_ids)) != 0)
return (error);
if (zfs_acl_ids_overquota(zfsvfs, &acl_ids, 0)) {
zfs_acl_ids_free(&acl_ids);
return (SET_ERROR(EDQUOT));
}
getnewvnode_reserve_();
tx = dmu_tx_create(zfsvfs->z_os);
dmu_tx_hold_sa_create(tx, acl_ids.z_aclp->z_acl_bytes +
ZFS_SA_BASE_ATTR_SIZE);
dmu_tx_hold_sa(tx, zp->z_sa_hdl, B_TRUE);
dmu_tx_hold_zap(tx, DMU_NEW_OBJECT, FALSE, NULL);
fuid_dirtied = zfsvfs->z_fuid_dirty;
if (fuid_dirtied)
zfs_fuid_txhold(zfsvfs, tx);
error = dmu_tx_assign(tx, TXG_WAIT);
if (error) {
zfs_acl_ids_free(&acl_ids);
dmu_tx_abort(tx);
getnewvnode_drop_reserve();
return (error);
}
zfs_mknode(zp, vap, tx, cr, IS_XATTR, &xzp, &acl_ids);
if (fuid_dirtied)
zfs_fuid_sync(zfsvfs, tx);
#ifdef ZFS_DEBUG
error = sa_lookup(xzp->z_sa_hdl, SA_ZPL_PARENT(zfsvfs),
&parent, sizeof (parent));
ASSERT(error == 0 && parent == zp->z_id);
#endif
VERIFY(0 == sa_update(zp->z_sa_hdl, SA_ZPL_XATTR(zfsvfs), &xzp->z_id,
sizeof (xzp->z_id), tx));
(void) zfs_log_create(zfsvfs->z_log, tx, TX_MKXATTR, zp,
xzp, "", NULL, acl_ids.z_fuidp, vap);
zfs_acl_ids_free(&acl_ids);
dmu_tx_commit(tx);
getnewvnode_drop_reserve();
*xvpp = xzp;
return (0);
}
/*
* Return a znode for the extended attribute directory for zp.
* ** If the directory does not already exist, it is created **
*
* IN: zp - znode to obtain attribute directory from
* cr - credentials of caller
* flags - flags from the VOP_LOOKUP call
*
* OUT: xzpp - pointer to extended attribute znode
*
* RETURN: 0 on success
* error number on failure
*/
int
zfs_get_xattrdir(znode_t *zp, znode_t **xzpp, cred_t *cr, int flags)
{
zfsvfs_t *zfsvfs = zp->z_zfsvfs;
znode_t *xzp;
vattr_t va;
int error;
top:
error = zfs_dirent_lookup(zp, "", &xzp, ZXATTR);
if (error)
return (error);
if (xzp != NULL) {
*xzpp = xzp;
return (0);
}
if (!(flags & CREATE_XATTR_DIR))
return (SET_ERROR(ENOATTR));
if (zfsvfs->z_vfs->vfs_flag & VFS_RDONLY) {
return (SET_ERROR(EROFS));
}
/*
* The ability to 'create' files in an attribute
* directory comes from the write_xattr permission on the base file.
*
* The ability to 'search' an attribute directory requires
* read_xattr permission on the base file.
*
* Once in a directory the ability to read/write attributes
* is controlled by the permissions on the attribute file.
*/
va.va_mask = AT_MODE | AT_UID | AT_GID;
va.va_type = VDIR;
va.va_mode = S_IFDIR | S_ISVTX | 0777;
zfs_fuid_map_ids(zp, cr, &va.va_uid, &va.va_gid);
error = zfs_make_xattrdir(zp, &va, xzpp, cr);
if (error == ERESTART) {
/* NB: we already did dmu_tx_wait() if necessary */
goto top;
}
if (error == 0)
VOP_UNLOCK1(ZTOV(*xzpp));
return (error);
}
/*
* Decide whether it is okay to remove within a sticky directory.
*
* In sticky directories, write access is not sufficient;
* you can remove entries from a directory only if:
*
* you own the directory,
* you own the entry,
* the entry is a plain file and you have write access,
* or you are privileged (checked in secpolicy...).
*
* The function returns 0 if remove access is granted.
*/
int
zfs_sticky_remove_access(znode_t *zdp, znode_t *zp, cred_t *cr)
{
uid_t uid;
uid_t downer;
uid_t fowner;
zfsvfs_t *zfsvfs = zdp->z_zfsvfs;
if (zdp->z_zfsvfs->z_replay)
return (0);
if ((zdp->z_mode & S_ISVTX) == 0)
return (0);
downer = zfs_fuid_map_id(zfsvfs, zdp->z_uid, cr, ZFS_OWNER);
fowner = zfs_fuid_map_id(zfsvfs, zp->z_uid, cr, ZFS_OWNER);
if ((uid = crgetuid(cr)) == downer || uid == fowner ||
(ZTOV(zp)->v_type == VREG &&
zfs_zaccess(zp, ACE_WRITE_DATA, 0, B_FALSE, cr) == 0))
return (0);
else
return (secpolicy_vnode_remove(ZTOV(zp), cr));
}