mirror_zfs/module/os/linux/zfs/zfs_vfsops.c
Rob Norris 8e002ee26e config: remove HAVE_D_PRUNE_ALIASES
Sponsored-by: https://despairlabs.com/sponsor/
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Reviewed-by: Tino Reichardt <milky-zfs@mcmilk.de>
Signed-off-by: Rob Norris <robn@despairlabs.com>
Closes #16479
2024-09-18 11:23:49 -07:00

2142 lines
54 KiB
C

/*
* 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 https://opensource.org/licenses/CDDL-1.0.
* 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) 2012, 2018 by Delphix. All rights reserved.
*/
/* Portions Copyright 2010 Robert Milkowski */
#include <sys/types.h>
#include <sys/param.h>
#include <sys/sysmacros.h>
#include <sys/kmem.h>
#include <sys/pathname.h>
#include <sys/vnode.h>
#include <sys/vfs.h>
#include <sys/mntent.h>
#include <sys/cmn_err.h>
#include <sys/zfs_znode.h>
#include <sys/zfs_vnops.h>
#include <sys/zfs_dir.h>
#include <sys/zil.h>
#include <sys/fs/zfs.h>
#include <sys/dmu.h>
#include <sys/dsl_prop.h>
#include <sys/dsl_dataset.h>
#include <sys/dsl_deleg.h>
#include <sys/spa.h>
#include <sys/zap.h>
#include <sys/sa.h>
#include <sys/sa_impl.h>
#include <sys/policy.h>
#include <sys/atomic.h>
#include <sys/zfs_ioctl.h>
#include <sys/zfs_ctldir.h>
#include <sys/zfs_fuid.h>
#include <sys/zfs_quota.h>
#include <sys/sunddi.h>
#include <sys/dmu_objset.h>
#include <sys/dsl_dir.h>
#include <sys/objlist.h>
#include <sys/zpl.h>
#include <linux/vfs_compat.h>
#include <linux/fs.h>
#include "zfs_comutil.h"
enum {
TOKEN_RO,
TOKEN_RW,
TOKEN_SETUID,
TOKEN_NOSETUID,
TOKEN_EXEC,
TOKEN_NOEXEC,
TOKEN_DEVICES,
TOKEN_NODEVICES,
TOKEN_DIRXATTR,
TOKEN_SAXATTR,
TOKEN_XATTR,
TOKEN_NOXATTR,
TOKEN_ATIME,
TOKEN_NOATIME,
TOKEN_RELATIME,
TOKEN_NORELATIME,
TOKEN_NBMAND,
TOKEN_NONBMAND,
TOKEN_MNTPOINT,
TOKEN_LAST,
};
static const match_table_t zpl_tokens = {
{ TOKEN_RO, MNTOPT_RO },
{ TOKEN_RW, MNTOPT_RW },
{ TOKEN_SETUID, MNTOPT_SETUID },
{ TOKEN_NOSETUID, MNTOPT_NOSETUID },
{ TOKEN_EXEC, MNTOPT_EXEC },
{ TOKEN_NOEXEC, MNTOPT_NOEXEC },
{ TOKEN_DEVICES, MNTOPT_DEVICES },
{ TOKEN_NODEVICES, MNTOPT_NODEVICES },
{ TOKEN_DIRXATTR, MNTOPT_DIRXATTR },
{ TOKEN_SAXATTR, MNTOPT_SAXATTR },
{ TOKEN_XATTR, MNTOPT_XATTR },
{ TOKEN_NOXATTR, MNTOPT_NOXATTR },
{ TOKEN_ATIME, MNTOPT_ATIME },
{ TOKEN_NOATIME, MNTOPT_NOATIME },
{ TOKEN_RELATIME, MNTOPT_RELATIME },
{ TOKEN_NORELATIME, MNTOPT_NORELATIME },
{ TOKEN_NBMAND, MNTOPT_NBMAND },
{ TOKEN_NONBMAND, MNTOPT_NONBMAND },
{ TOKEN_MNTPOINT, MNTOPT_MNTPOINT "=%s" },
{ TOKEN_LAST, NULL },
};
static void
zfsvfs_vfs_free(vfs_t *vfsp)
{
if (vfsp != NULL) {
if (vfsp->vfs_mntpoint != NULL)
kmem_strfree(vfsp->vfs_mntpoint);
kmem_free(vfsp, sizeof (vfs_t));
}
}
static int
zfsvfs_parse_option(char *option, int token, substring_t *args, vfs_t *vfsp)
{
switch (token) {
case TOKEN_RO:
vfsp->vfs_readonly = B_TRUE;
vfsp->vfs_do_readonly = B_TRUE;
break;
case TOKEN_RW:
vfsp->vfs_readonly = B_FALSE;
vfsp->vfs_do_readonly = B_TRUE;
break;
case TOKEN_SETUID:
vfsp->vfs_setuid = B_TRUE;
vfsp->vfs_do_setuid = B_TRUE;
break;
case TOKEN_NOSETUID:
vfsp->vfs_setuid = B_FALSE;
vfsp->vfs_do_setuid = B_TRUE;
break;
case TOKEN_EXEC:
vfsp->vfs_exec = B_TRUE;
vfsp->vfs_do_exec = B_TRUE;
break;
case TOKEN_NOEXEC:
vfsp->vfs_exec = B_FALSE;
vfsp->vfs_do_exec = B_TRUE;
break;
case TOKEN_DEVICES:
vfsp->vfs_devices = B_TRUE;
vfsp->vfs_do_devices = B_TRUE;
break;
case TOKEN_NODEVICES:
vfsp->vfs_devices = B_FALSE;
vfsp->vfs_do_devices = B_TRUE;
break;
case TOKEN_DIRXATTR:
vfsp->vfs_xattr = ZFS_XATTR_DIR;
vfsp->vfs_do_xattr = B_TRUE;
break;
case TOKEN_SAXATTR:
vfsp->vfs_xattr = ZFS_XATTR_SA;
vfsp->vfs_do_xattr = B_TRUE;
break;
case TOKEN_XATTR:
vfsp->vfs_xattr = ZFS_XATTR_DIR;
vfsp->vfs_do_xattr = B_TRUE;
break;
case TOKEN_NOXATTR:
vfsp->vfs_xattr = ZFS_XATTR_OFF;
vfsp->vfs_do_xattr = B_TRUE;
break;
case TOKEN_ATIME:
vfsp->vfs_atime = B_TRUE;
vfsp->vfs_do_atime = B_TRUE;
break;
case TOKEN_NOATIME:
vfsp->vfs_atime = B_FALSE;
vfsp->vfs_do_atime = B_TRUE;
break;
case TOKEN_RELATIME:
vfsp->vfs_relatime = B_TRUE;
vfsp->vfs_do_relatime = B_TRUE;
break;
case TOKEN_NORELATIME:
vfsp->vfs_relatime = B_FALSE;
vfsp->vfs_do_relatime = B_TRUE;
break;
case TOKEN_NBMAND:
vfsp->vfs_nbmand = B_TRUE;
vfsp->vfs_do_nbmand = B_TRUE;
break;
case TOKEN_NONBMAND:
vfsp->vfs_nbmand = B_FALSE;
vfsp->vfs_do_nbmand = B_TRUE;
break;
case TOKEN_MNTPOINT:
vfsp->vfs_mntpoint = match_strdup(&args[0]);
if (vfsp->vfs_mntpoint == NULL)
return (SET_ERROR(ENOMEM));
break;
default:
break;
}
return (0);
}
/*
* Parse the raw mntopts and return a vfs_t describing the options.
*/
static int
zfsvfs_parse_options(char *mntopts, vfs_t **vfsp)
{
vfs_t *tmp_vfsp;
int error;
tmp_vfsp = kmem_zalloc(sizeof (vfs_t), KM_SLEEP);
if (mntopts != NULL) {
substring_t args[MAX_OPT_ARGS];
char *tmp_mntopts, *p, *t;
int token;
tmp_mntopts = t = kmem_strdup(mntopts);
if (tmp_mntopts == NULL)
return (SET_ERROR(ENOMEM));
while ((p = strsep(&t, ",")) != NULL) {
if (!*p)
continue;
args[0].to = args[0].from = NULL;
token = match_token(p, zpl_tokens, args);
error = zfsvfs_parse_option(p, token, args, tmp_vfsp);
if (error) {
kmem_strfree(tmp_mntopts);
zfsvfs_vfs_free(tmp_vfsp);
return (error);
}
}
kmem_strfree(tmp_mntopts);
}
*vfsp = tmp_vfsp;
return (0);
}
boolean_t
zfs_is_readonly(zfsvfs_t *zfsvfs)
{
return (!!(zfsvfs->z_sb->s_flags & SB_RDONLY));
}
int
zfs_sync(struct super_block *sb, int wait, cred_t *cr)
{
(void) cr;
zfsvfs_t *zfsvfs = sb->s_fs_info;
/*
* Semantically, the only requirement is that the sync be initiated.
* The DMU syncs out txgs frequently, so there's nothing to do.
*/
if (!wait)
return (0);
if (zfsvfs != NULL) {
/*
* Sync a specific filesystem.
*/
dsl_pool_t *dp;
int error;
if ((error = zfs_enter(zfsvfs, FTAG)) != 0)
return (error);
dp = dmu_objset_pool(zfsvfs->z_os);
/*
* If the system is shutting down, then skip any
* filesystems which may exist on a suspended pool.
*/
if (spa_suspended(dp->dp_spa)) {
zfs_exit(zfsvfs, FTAG);
return (0);
}
if (zfsvfs->z_log != NULL)
zil_commit(zfsvfs->z_log, 0);
zfs_exit(zfsvfs, FTAG);
} else {
/*
* Sync all ZFS filesystems. This is what happens when you
* run sync(1). Unlike other filesystems, ZFS honors the
* request by waiting for all pools to commit all dirty data.
*/
spa_sync_allpools();
}
return (0);
}
static void
atime_changed_cb(void *arg, uint64_t newval)
{
zfsvfs_t *zfsvfs = arg;
struct super_block *sb = zfsvfs->z_sb;
if (sb == NULL)
return;
/*
* Update SB_NOATIME bit in VFS super block. Since atime update is
* determined by atime_needs_update(), atime_needs_update() needs to
* return false if atime is turned off, and not unconditionally return
* false if atime is turned on.
*/
if (newval)
sb->s_flags &= ~SB_NOATIME;
else
sb->s_flags |= SB_NOATIME;
}
static void
relatime_changed_cb(void *arg, uint64_t newval)
{
((zfsvfs_t *)arg)->z_relatime = newval;
}
static void
xattr_changed_cb(void *arg, uint64_t newval)
{
zfsvfs_t *zfsvfs = arg;
if (newval == ZFS_XATTR_OFF) {
zfsvfs->z_flags &= ~ZSB_XATTR;
} else {
zfsvfs->z_flags |= ZSB_XATTR;
if (newval == ZFS_XATTR_SA)
zfsvfs->z_xattr_sa = B_TRUE;
else
zfsvfs->z_xattr_sa = B_FALSE;
}
}
static void
acltype_changed_cb(void *arg, uint64_t newval)
{
zfsvfs_t *zfsvfs = arg;
switch (newval) {
case ZFS_ACLTYPE_NFSV4:
case ZFS_ACLTYPE_OFF:
zfsvfs->z_acl_type = ZFS_ACLTYPE_OFF;
zfsvfs->z_sb->s_flags &= ~SB_POSIXACL;
break;
case ZFS_ACLTYPE_POSIX:
#ifdef CONFIG_FS_POSIX_ACL
zfsvfs->z_acl_type = ZFS_ACLTYPE_POSIX;
zfsvfs->z_sb->s_flags |= SB_POSIXACL;
#else
zfsvfs->z_acl_type = ZFS_ACLTYPE_OFF;
zfsvfs->z_sb->s_flags &= ~SB_POSIXACL;
#endif /* CONFIG_FS_POSIX_ACL */
break;
default:
break;
}
}
static void
blksz_changed_cb(void *arg, uint64_t newval)
{
zfsvfs_t *zfsvfs = arg;
ASSERT3U(newval, <=, spa_maxblocksize(dmu_objset_spa(zfsvfs->z_os)));
ASSERT3U(newval, >=, SPA_MINBLOCKSIZE);
ASSERT(ISP2(newval));
zfsvfs->z_max_blksz = newval;
}
static void
readonly_changed_cb(void *arg, uint64_t newval)
{
zfsvfs_t *zfsvfs = arg;
struct super_block *sb = zfsvfs->z_sb;
if (sb == NULL)
return;
if (newval)
sb->s_flags |= SB_RDONLY;
else
sb->s_flags &= ~SB_RDONLY;
}
static void
devices_changed_cb(void *arg, uint64_t newval)
{
}
static void
setuid_changed_cb(void *arg, uint64_t newval)
{
}
static void
exec_changed_cb(void *arg, uint64_t newval)
{
}
static void
nbmand_changed_cb(void *arg, uint64_t newval)
{
zfsvfs_t *zfsvfs = arg;
struct super_block *sb = zfsvfs->z_sb;
if (sb == NULL)
return;
if (newval == TRUE)
sb->s_flags |= SB_MANDLOCK;
else
sb->s_flags &= ~SB_MANDLOCK;
}
static void
snapdir_changed_cb(void *arg, uint64_t newval)
{
((zfsvfs_t *)arg)->z_show_ctldir = newval;
}
static void
acl_mode_changed_cb(void *arg, uint64_t newval)
{
zfsvfs_t *zfsvfs = arg;
zfsvfs->z_acl_mode = newval;
}
static void
acl_inherit_changed_cb(void *arg, uint64_t newval)
{
((zfsvfs_t *)arg)->z_acl_inherit = newval;
}
static int
zfs_register_callbacks(vfs_t *vfsp)
{
struct dsl_dataset *ds = NULL;
objset_t *os = NULL;
zfsvfs_t *zfsvfs = NULL;
int error = 0;
ASSERT(vfsp);
zfsvfs = vfsp->vfs_data;
ASSERT(zfsvfs);
os = zfsvfs->z_os;
/*
* The act of registering our callbacks will destroy any mount
* options we may have. In order to enable temporary overrides
* of mount options, we stash away the current values and
* restore them after we register the callbacks.
*/
if (zfs_is_readonly(zfsvfs) || !spa_writeable(dmu_objset_spa(os))) {
vfsp->vfs_do_readonly = B_TRUE;
vfsp->vfs_readonly = B_TRUE;
}
/*
* Register property callbacks.
*
* It would probably be fine to just check for i/o error from
* the first prop_register(), but I guess I like to go
* overboard...
*/
ds = dmu_objset_ds(os);
dsl_pool_config_enter(dmu_objset_pool(os), FTAG);
error = dsl_prop_register(ds,
zfs_prop_to_name(ZFS_PROP_ATIME), atime_changed_cb, zfsvfs);
error = error ? error : dsl_prop_register(ds,
zfs_prop_to_name(ZFS_PROP_RELATIME), relatime_changed_cb, zfsvfs);
error = error ? error : dsl_prop_register(ds,
zfs_prop_to_name(ZFS_PROP_XATTR), xattr_changed_cb, zfsvfs);
error = error ? error : dsl_prop_register(ds,
zfs_prop_to_name(ZFS_PROP_RECORDSIZE), blksz_changed_cb, zfsvfs);
error = error ? error : dsl_prop_register(ds,
zfs_prop_to_name(ZFS_PROP_READONLY), readonly_changed_cb, zfsvfs);
error = error ? error : dsl_prop_register(ds,
zfs_prop_to_name(ZFS_PROP_DEVICES), devices_changed_cb, zfsvfs);
error = error ? error : dsl_prop_register(ds,
zfs_prop_to_name(ZFS_PROP_SETUID), setuid_changed_cb, zfsvfs);
error = error ? error : dsl_prop_register(ds,
zfs_prop_to_name(ZFS_PROP_EXEC), exec_changed_cb, zfsvfs);
error = error ? error : dsl_prop_register(ds,
zfs_prop_to_name(ZFS_PROP_SNAPDIR), snapdir_changed_cb, zfsvfs);
error = error ? error : dsl_prop_register(ds,
zfs_prop_to_name(ZFS_PROP_ACLTYPE), acltype_changed_cb, zfsvfs);
error = error ? error : dsl_prop_register(ds,
zfs_prop_to_name(ZFS_PROP_ACLMODE), acl_mode_changed_cb, zfsvfs);
error = error ? error : dsl_prop_register(ds,
zfs_prop_to_name(ZFS_PROP_ACLINHERIT), acl_inherit_changed_cb,
zfsvfs);
error = error ? error : dsl_prop_register(ds,
zfs_prop_to_name(ZFS_PROP_NBMAND), nbmand_changed_cb, zfsvfs);
dsl_pool_config_exit(dmu_objset_pool(os), FTAG);
if (error)
goto unregister;
/*
* Invoke our callbacks to restore temporary mount options.
*/
if (vfsp->vfs_do_readonly)
readonly_changed_cb(zfsvfs, vfsp->vfs_readonly);
if (vfsp->vfs_do_setuid)
setuid_changed_cb(zfsvfs, vfsp->vfs_setuid);
if (vfsp->vfs_do_exec)
exec_changed_cb(zfsvfs, vfsp->vfs_exec);
if (vfsp->vfs_do_devices)
devices_changed_cb(zfsvfs, vfsp->vfs_devices);
if (vfsp->vfs_do_xattr)
xattr_changed_cb(zfsvfs, vfsp->vfs_xattr);
if (vfsp->vfs_do_atime)
atime_changed_cb(zfsvfs, vfsp->vfs_atime);
if (vfsp->vfs_do_relatime)
relatime_changed_cb(zfsvfs, vfsp->vfs_relatime);
if (vfsp->vfs_do_nbmand)
nbmand_changed_cb(zfsvfs, vfsp->vfs_nbmand);
return (0);
unregister:
dsl_prop_unregister_all(ds, zfsvfs);
return (error);
}
/*
* Takes a dataset, a property, a value and that value's setpoint as
* found in the ZAP. Checks if the property has been changed in the vfs.
* If so, val and setpoint will be overwritten with updated content.
* Otherwise, they are left unchanged.
*/
int
zfs_get_temporary_prop(dsl_dataset_t *ds, zfs_prop_t zfs_prop, uint64_t *val,
char *setpoint)
{
int error;
zfsvfs_t *zfvp;
vfs_t *vfsp;
objset_t *os;
uint64_t tmp = *val;
error = dmu_objset_from_ds(ds, &os);
if (error != 0)
return (error);
if (dmu_objset_type(os) != DMU_OST_ZFS)
return (EINVAL);
mutex_enter(&os->os_user_ptr_lock);
zfvp = dmu_objset_get_user(os);
mutex_exit(&os->os_user_ptr_lock);
if (zfvp == NULL)
return (ESRCH);
vfsp = zfvp->z_vfs;
switch (zfs_prop) {
case ZFS_PROP_ATIME:
if (vfsp->vfs_do_atime)
tmp = vfsp->vfs_atime;
break;
case ZFS_PROP_RELATIME:
if (vfsp->vfs_do_relatime)
tmp = vfsp->vfs_relatime;
break;
case ZFS_PROP_DEVICES:
if (vfsp->vfs_do_devices)
tmp = vfsp->vfs_devices;
break;
case ZFS_PROP_EXEC:
if (vfsp->vfs_do_exec)
tmp = vfsp->vfs_exec;
break;
case ZFS_PROP_SETUID:
if (vfsp->vfs_do_setuid)
tmp = vfsp->vfs_setuid;
break;
case ZFS_PROP_READONLY:
if (vfsp->vfs_do_readonly)
tmp = vfsp->vfs_readonly;
break;
case ZFS_PROP_XATTR:
if (vfsp->vfs_do_xattr)
tmp = vfsp->vfs_xattr;
break;
case ZFS_PROP_NBMAND:
if (vfsp->vfs_do_nbmand)
tmp = vfsp->vfs_nbmand;
break;
default:
return (ENOENT);
}
if (tmp != *val) {
if (setpoint)
(void) strcpy(setpoint, "temporary");
*val = tmp;
}
return (0);
}
/*
* Associate this zfsvfs with the given objset, which must be owned.
* This will cache a bunch of on-disk state from the objset in the
* zfsvfs.
*/
static int
zfsvfs_init(zfsvfs_t *zfsvfs, objset_t *os)
{
int error;
uint64_t val;
zfsvfs->z_max_blksz = SPA_OLD_MAXBLOCKSIZE;
zfsvfs->z_show_ctldir = ZFS_SNAPDIR_VISIBLE;
zfsvfs->z_os = os;
error = zfs_get_zplprop(os, ZFS_PROP_VERSION, &zfsvfs->z_version);
if (error != 0)
return (error);
if (zfsvfs->z_version >
zfs_zpl_version_map(spa_version(dmu_objset_spa(os)))) {
(void) printk("Can't mount a version %lld file system "
"on a version %lld pool\n. Pool must be upgraded to mount "
"this file system.\n", (u_longlong_t)zfsvfs->z_version,
(u_longlong_t)spa_version(dmu_objset_spa(os)));
return (SET_ERROR(ENOTSUP));
}
error = zfs_get_zplprop(os, ZFS_PROP_NORMALIZE, &val);
if (error != 0)
return (error);
zfsvfs->z_norm = (int)val;
error = zfs_get_zplprop(os, ZFS_PROP_UTF8ONLY, &val);
if (error != 0)
return (error);
zfsvfs->z_utf8 = (val != 0);
error = zfs_get_zplprop(os, ZFS_PROP_CASE, &val);
if (error != 0)
return (error);
zfsvfs->z_case = (uint_t)val;
if ((error = zfs_get_zplprop(os, ZFS_PROP_ACLTYPE, &val)) != 0)
return (error);
zfsvfs->z_acl_type = (uint_t)val;
/*
* Fold case on file systems that are always or sometimes case
* insensitive.
*/
if (zfsvfs->z_case == ZFS_CASE_INSENSITIVE ||
zfsvfs->z_case == ZFS_CASE_MIXED)
zfsvfs->z_norm |= U8_TEXTPREP_TOUPPER;
zfsvfs->z_use_fuids = USE_FUIDS(zfsvfs->z_version, zfsvfs->z_os);
zfsvfs->z_use_sa = USE_SA(zfsvfs->z_version, zfsvfs->z_os);
uint64_t sa_obj = 0;
if (zfsvfs->z_use_sa) {
/* should either have both of these objects or none */
error = zap_lookup(os, MASTER_NODE_OBJ, ZFS_SA_ATTRS, 8, 1,
&sa_obj);
if (error != 0)
return (error);
error = zfs_get_zplprop(os, ZFS_PROP_XATTR, &val);
if ((error == 0) && (val == ZFS_XATTR_SA))
zfsvfs->z_xattr_sa = B_TRUE;
}
error = zap_lookup(os, MASTER_NODE_OBJ, ZFS_ROOT_OBJ, 8, 1,
&zfsvfs->z_root);
if (error != 0)
return (error);
ASSERT(zfsvfs->z_root != 0);
error = zap_lookup(os, MASTER_NODE_OBJ, ZFS_UNLINKED_SET, 8, 1,
&zfsvfs->z_unlinkedobj);
if (error != 0)
return (error);
error = zap_lookup(os, MASTER_NODE_OBJ,
zfs_userquota_prop_prefixes[ZFS_PROP_USERQUOTA],
8, 1, &zfsvfs->z_userquota_obj);
if (error == ENOENT)
zfsvfs->z_userquota_obj = 0;
else if (error != 0)
return (error);
error = zap_lookup(os, MASTER_NODE_OBJ,
zfs_userquota_prop_prefixes[ZFS_PROP_GROUPQUOTA],
8, 1, &zfsvfs->z_groupquota_obj);
if (error == ENOENT)
zfsvfs->z_groupquota_obj = 0;
else if (error != 0)
return (error);
error = zap_lookup(os, MASTER_NODE_OBJ,
zfs_userquota_prop_prefixes[ZFS_PROP_PROJECTQUOTA],
8, 1, &zfsvfs->z_projectquota_obj);
if (error == ENOENT)
zfsvfs->z_projectquota_obj = 0;
else if (error != 0)
return (error);
error = zap_lookup(os, MASTER_NODE_OBJ,
zfs_userquota_prop_prefixes[ZFS_PROP_USEROBJQUOTA],
8, 1, &zfsvfs->z_userobjquota_obj);
if (error == ENOENT)
zfsvfs->z_userobjquota_obj = 0;
else if (error != 0)
return (error);
error = zap_lookup(os, MASTER_NODE_OBJ,
zfs_userquota_prop_prefixes[ZFS_PROP_GROUPOBJQUOTA],
8, 1, &zfsvfs->z_groupobjquota_obj);
if (error == ENOENT)
zfsvfs->z_groupobjquota_obj = 0;
else if (error != 0)
return (error);
error = zap_lookup(os, MASTER_NODE_OBJ,
zfs_userquota_prop_prefixes[ZFS_PROP_PROJECTOBJQUOTA],
8, 1, &zfsvfs->z_projectobjquota_obj);
if (error == ENOENT)
zfsvfs->z_projectobjquota_obj = 0;
else if (error != 0)
return (error);
error = zap_lookup(os, MASTER_NODE_OBJ, ZFS_FUID_TABLES, 8, 1,
&zfsvfs->z_fuid_obj);
if (error == ENOENT)
zfsvfs->z_fuid_obj = 0;
else if (error != 0)
return (error);
error = zap_lookup(os, MASTER_NODE_OBJ, ZFS_SHARES_DIR, 8, 1,
&zfsvfs->z_shares_dir);
if (error == ENOENT)
zfsvfs->z_shares_dir = 0;
else if (error != 0)
return (error);
error = sa_setup(os, sa_obj, zfs_attr_table, ZPL_END,
&zfsvfs->z_attr_table);
if (error != 0)
return (error);
if (zfsvfs->z_version >= ZPL_VERSION_SA)
sa_register_update_callback(os, zfs_sa_upgrade);
return (0);
}
int
zfsvfs_create(const char *osname, boolean_t readonly, zfsvfs_t **zfvp)
{
objset_t *os;
zfsvfs_t *zfsvfs;
int error;
boolean_t ro = (readonly || (strchr(osname, '@') != NULL));
zfsvfs = kmem_zalloc(sizeof (zfsvfs_t), KM_SLEEP);
error = dmu_objset_own(osname, DMU_OST_ZFS, ro, B_TRUE, zfsvfs, &os);
if (error != 0) {
kmem_free(zfsvfs, sizeof (zfsvfs_t));
return (error);
}
error = zfsvfs_create_impl(zfvp, zfsvfs, os);
return (error);
}
/*
* Note: zfsvfs is assumed to be malloc'd, and will be freed by this function
* on a failure. Do not pass in a statically allocated zfsvfs.
*/
int
zfsvfs_create_impl(zfsvfs_t **zfvp, zfsvfs_t *zfsvfs, objset_t *os)
{
int error;
zfsvfs->z_vfs = NULL;
zfsvfs->z_sb = NULL;
zfsvfs->z_parent = zfsvfs;
mutex_init(&zfsvfs->z_znodes_lock, NULL, MUTEX_DEFAULT, NULL);
mutex_init(&zfsvfs->z_lock, NULL, MUTEX_DEFAULT, NULL);
list_create(&zfsvfs->z_all_znodes, sizeof (znode_t),
offsetof(znode_t, z_link_node));
ZFS_TEARDOWN_INIT(zfsvfs);
rw_init(&zfsvfs->z_teardown_inactive_lock, NULL, RW_DEFAULT, NULL);
rw_init(&zfsvfs->z_fuid_lock, NULL, RW_DEFAULT, NULL);
int size = MIN(1 << (highbit64(zfs_object_mutex_size) - 1),
ZFS_OBJ_MTX_MAX);
zfsvfs->z_hold_size = size;
zfsvfs->z_hold_trees = vmem_zalloc(sizeof (avl_tree_t) * size,
KM_SLEEP);
zfsvfs->z_hold_locks = vmem_zalloc(sizeof (kmutex_t) * size, KM_SLEEP);
for (int i = 0; i != size; i++) {
avl_create(&zfsvfs->z_hold_trees[i], zfs_znode_hold_compare,
sizeof (znode_hold_t), offsetof(znode_hold_t, zh_node));
mutex_init(&zfsvfs->z_hold_locks[i], NULL, MUTEX_DEFAULT, NULL);
}
error = zfsvfs_init(zfsvfs, os);
if (error != 0) {
dmu_objset_disown(os, B_TRUE, zfsvfs);
*zfvp = NULL;
zfsvfs_free(zfsvfs);
return (error);
}
zfsvfs->z_drain_task = TASKQID_INVALID;
zfsvfs->z_draining = B_FALSE;
zfsvfs->z_drain_cancel = B_TRUE;
*zfvp = zfsvfs;
return (0);
}
static int
zfsvfs_setup(zfsvfs_t *zfsvfs, boolean_t mounting)
{
int error;
boolean_t readonly = zfs_is_readonly(zfsvfs);
error = zfs_register_callbacks(zfsvfs->z_vfs);
if (error)
return (error);
/*
* If we are not mounting (ie: online recv), then we don't
* have to worry about replaying the log as we blocked all
* operations out since we closed the ZIL.
*/
if (mounting) {
ASSERT3P(zfsvfs->z_kstat.dk_kstats, ==, NULL);
error = dataset_kstats_create(&zfsvfs->z_kstat, zfsvfs->z_os);
if (error)
return (error);
zfsvfs->z_log = zil_open(zfsvfs->z_os, zfs_get_data,
&zfsvfs->z_kstat.dk_zil_sums);
/*
* During replay we remove the read only flag to
* allow replays to succeed.
*/
if (readonly != 0) {
readonly_changed_cb(zfsvfs, B_FALSE);
} else {
zap_stats_t zs;
if (zap_get_stats(zfsvfs->z_os, zfsvfs->z_unlinkedobj,
&zs) == 0) {
dataset_kstats_update_nunlinks_kstat(
&zfsvfs->z_kstat, zs.zs_num_entries);
dprintf_ds(zfsvfs->z_os->os_dsl_dataset,
"num_entries in unlinked set: %llu",
zs.zs_num_entries);
}
zfs_unlinked_drain(zfsvfs);
dsl_dir_t *dd = zfsvfs->z_os->os_dsl_dataset->ds_dir;
dd->dd_activity_cancelled = B_FALSE;
}
/*
* Parse and replay the intent log.
*
* Because of ziltest, this must be done after
* zfs_unlinked_drain(). (Further note: ziltest
* doesn't use readonly mounts, where
* zfs_unlinked_drain() isn't called.) This is because
* ziltest causes spa_sync() to think it's committed,
* but actually it is not, so the intent log contains
* many txg's worth of changes.
*
* In particular, if object N is in the unlinked set in
* the last txg to actually sync, then it could be
* actually freed in a later txg and then reallocated
* in a yet later txg. This would write a "create
* object N" record to the intent log. Normally, this
* would be fine because the spa_sync() would have
* written out the fact that object N is free, before
* we could write the "create object N" intent log
* record.
*
* But when we are in ziltest mode, we advance the "open
* txg" without actually spa_sync()-ing the changes to
* disk. So we would see that object N is still
* allocated and in the unlinked set, and there is an
* intent log record saying to allocate it.
*/
if (spa_writeable(dmu_objset_spa(zfsvfs->z_os))) {
if (zil_replay_disable) {
zil_destroy(zfsvfs->z_log, B_FALSE);
} else {
zfsvfs->z_replay = B_TRUE;
zil_replay(zfsvfs->z_os, zfsvfs,
zfs_replay_vector);
zfsvfs->z_replay = B_FALSE;
}
}
/* restore readonly bit */
if (readonly != 0)
readonly_changed_cb(zfsvfs, B_TRUE);
} else {
ASSERT3P(zfsvfs->z_kstat.dk_kstats, !=, NULL);
zfsvfs->z_log = zil_open(zfsvfs->z_os, zfs_get_data,
&zfsvfs->z_kstat.dk_zil_sums);
}
/*
* Set the objset user_ptr to track its zfsvfs.
*/
mutex_enter(&zfsvfs->z_os->os_user_ptr_lock);
dmu_objset_set_user(zfsvfs->z_os, zfsvfs);
mutex_exit(&zfsvfs->z_os->os_user_ptr_lock);
return (0);
}
void
zfsvfs_free(zfsvfs_t *zfsvfs)
{
int i, size = zfsvfs->z_hold_size;
zfs_fuid_destroy(zfsvfs);
mutex_destroy(&zfsvfs->z_znodes_lock);
mutex_destroy(&zfsvfs->z_lock);
list_destroy(&zfsvfs->z_all_znodes);
ZFS_TEARDOWN_DESTROY(zfsvfs);
rw_destroy(&zfsvfs->z_teardown_inactive_lock);
rw_destroy(&zfsvfs->z_fuid_lock);
for (i = 0; i != size; i++) {
avl_destroy(&zfsvfs->z_hold_trees[i]);
mutex_destroy(&zfsvfs->z_hold_locks[i]);
}
vmem_free(zfsvfs->z_hold_trees, sizeof (avl_tree_t) * size);
vmem_free(zfsvfs->z_hold_locks, sizeof (kmutex_t) * size);
zfsvfs_vfs_free(zfsvfs->z_vfs);
dataset_kstats_destroy(&zfsvfs->z_kstat);
kmem_free(zfsvfs, sizeof (zfsvfs_t));
}
static void
zfs_set_fuid_feature(zfsvfs_t *zfsvfs)
{
zfsvfs->z_use_fuids = USE_FUIDS(zfsvfs->z_version, zfsvfs->z_os);
zfsvfs->z_use_sa = USE_SA(zfsvfs->z_version, zfsvfs->z_os);
}
static void
zfs_unregister_callbacks(zfsvfs_t *zfsvfs)
{
objset_t *os = zfsvfs->z_os;
if (!dmu_objset_is_snapshot(os))
dsl_prop_unregister_all(dmu_objset_ds(os), zfsvfs);
}
#ifdef HAVE_MLSLABEL
/*
* Check that the hex label string is appropriate for the dataset being
* mounted into the global_zone proper.
*
* Return an error if the hex label string is not default or
* admin_low/admin_high. For admin_low labels, the corresponding
* dataset must be readonly.
*/
int
zfs_check_global_label(const char *dsname, const char *hexsl)
{
if (strcasecmp(hexsl, ZFS_MLSLABEL_DEFAULT) == 0)
return (0);
if (strcasecmp(hexsl, ADMIN_HIGH) == 0)
return (0);
if (strcasecmp(hexsl, ADMIN_LOW) == 0) {
/* must be readonly */
uint64_t rdonly;
if (dsl_prop_get_integer(dsname,
zfs_prop_to_name(ZFS_PROP_READONLY), &rdonly, NULL))
return (SET_ERROR(EACCES));
return (rdonly ? 0 : SET_ERROR(EACCES));
}
return (SET_ERROR(EACCES));
}
#endif /* HAVE_MLSLABEL */
static int
zfs_statfs_project(zfsvfs_t *zfsvfs, znode_t *zp, struct kstatfs *statp,
uint32_t bshift)
{
char buf[20 + DMU_OBJACCT_PREFIX_LEN];
uint64_t offset = DMU_OBJACCT_PREFIX_LEN;
uint64_t quota;
uint64_t used;
int err;
strlcpy(buf, DMU_OBJACCT_PREFIX, DMU_OBJACCT_PREFIX_LEN + 1);
err = zfs_id_to_fuidstr(zfsvfs, NULL, zp->z_projid, buf + offset,
sizeof (buf) - offset, B_FALSE);
if (err)
return (err);
if (zfsvfs->z_projectquota_obj == 0)
goto objs;
err = zap_lookup(zfsvfs->z_os, zfsvfs->z_projectquota_obj,
buf + offset, 8, 1, &quota);
if (err == ENOENT)
goto objs;
else if (err)
return (err);
err = zap_lookup(zfsvfs->z_os, DMU_PROJECTUSED_OBJECT,
buf + offset, 8, 1, &used);
if (unlikely(err == ENOENT)) {
uint32_t blksize;
u_longlong_t nblocks;
/*
* Quota accounting is async, so it is possible race case.
* There is at least one object with the given project ID.
*/
sa_object_size(zp->z_sa_hdl, &blksize, &nblocks);
if (unlikely(zp->z_blksz == 0))
blksize = zfsvfs->z_max_blksz;
used = blksize * nblocks;
} else if (err) {
return (err);
}
statp->f_blocks = quota >> bshift;
statp->f_bfree = (quota > used) ? ((quota - used) >> bshift) : 0;
statp->f_bavail = statp->f_bfree;
objs:
if (zfsvfs->z_projectobjquota_obj == 0)
return (0);
err = zap_lookup(zfsvfs->z_os, zfsvfs->z_projectobjquota_obj,
buf + offset, 8, 1, &quota);
if (err == ENOENT)
return (0);
else if (err)
return (err);
err = zap_lookup(zfsvfs->z_os, DMU_PROJECTUSED_OBJECT,
buf, 8, 1, &used);
if (unlikely(err == ENOENT)) {
/*
* Quota accounting is async, so it is possible race case.
* There is at least one object with the given project ID.
*/
used = 1;
} else if (err) {
return (err);
}
statp->f_files = quota;
statp->f_ffree = (quota > used) ? (quota - used) : 0;
return (0);
}
int
zfs_statvfs(struct inode *ip, struct kstatfs *statp)
{
zfsvfs_t *zfsvfs = ITOZSB(ip);
uint64_t refdbytes, availbytes, usedobjs, availobjs;
int err = 0;
if ((err = zfs_enter(zfsvfs, FTAG)) != 0)
return (err);
dmu_objset_space(zfsvfs->z_os,
&refdbytes, &availbytes, &usedobjs, &availobjs);
uint64_t fsid = dmu_objset_fsid_guid(zfsvfs->z_os);
/*
* The underlying storage pool actually uses multiple block
* size. Under Solaris frsize (fragment size) is reported as
* the smallest block size we support, and bsize (block size)
* as the filesystem's maximum block size. Unfortunately,
* under Linux the fragment size and block size are often used
* interchangeably. Thus we are forced to report both of them
* as the filesystem's maximum block size.
*/
statp->f_frsize = zfsvfs->z_max_blksz;
statp->f_bsize = zfsvfs->z_max_blksz;
uint32_t bshift = fls(statp->f_bsize) - 1;
/*
* The following report "total" blocks of various kinds in
* the file system, but reported in terms of f_bsize - the
* "preferred" size.
*/
/* Round up so we never have a filesystem using 0 blocks. */
refdbytes = P2ROUNDUP(refdbytes, statp->f_bsize);
statp->f_blocks = (refdbytes + availbytes) >> bshift;
statp->f_bfree = availbytes >> bshift;
statp->f_bavail = statp->f_bfree; /* no root reservation */
/*
* statvfs() should really be called statufs(), because it assumes
* static metadata. ZFS doesn't preallocate files, so the best
* we can do is report the max that could possibly fit in f_files,
* and that minus the number actually used in f_ffree.
* For f_ffree, report the smaller of the number of objects available
* and the number of blocks (each object will take at least a block).
*/
statp->f_ffree = MIN(availobjs, availbytes >> DNODE_SHIFT);
statp->f_files = statp->f_ffree + usedobjs;
statp->f_fsid.val[0] = (uint32_t)fsid;
statp->f_fsid.val[1] = (uint32_t)(fsid >> 32);
statp->f_type = ZFS_SUPER_MAGIC;
statp->f_namelen = MAXNAMELEN - 1;
/*
* We have all of 40 characters to stuff a string here.
* Is there anything useful we could/should provide?
*/
memset(statp->f_spare, 0, sizeof (statp->f_spare));
if (dmu_objset_projectquota_enabled(zfsvfs->z_os) &&
dmu_objset_projectquota_present(zfsvfs->z_os)) {
znode_t *zp = ITOZ(ip);
if (zp->z_pflags & ZFS_PROJINHERIT && zp->z_projid &&
zpl_is_valid_projid(zp->z_projid))
err = zfs_statfs_project(zfsvfs, zp, statp, bshift);
}
zfs_exit(zfsvfs, FTAG);
return (err);
}
static int
zfs_root(zfsvfs_t *zfsvfs, struct inode **ipp)
{
znode_t *rootzp;
int error;
if ((error = zfs_enter(zfsvfs, FTAG)) != 0)
return (error);
error = zfs_zget(zfsvfs, zfsvfs->z_root, &rootzp);
if (error == 0)
*ipp = ZTOI(rootzp);
zfs_exit(zfsvfs, FTAG);
return (error);
}
/*
* Linux kernels older than 3.1 do not support a per-filesystem shrinker.
* To accommodate this we must improvise and manually walk the list of znodes
* attempting to prune dentries in order to be able to drop the inodes.
*
* To avoid scanning the same znodes multiple times they are always rotated
* to the end of the z_all_znodes list. New znodes are inserted at the
* end of the list so we're always scanning the oldest znodes first.
*/
static int
zfs_prune_aliases(zfsvfs_t *zfsvfs, unsigned long nr_to_scan)
{
znode_t **zp_array, *zp;
int max_array = MIN(nr_to_scan, PAGE_SIZE * 8 / sizeof (znode_t *));
int objects = 0;
int i = 0, j = 0;
zp_array = vmem_zalloc(max_array * sizeof (znode_t *), KM_SLEEP);
mutex_enter(&zfsvfs->z_znodes_lock);
while ((zp = list_head(&zfsvfs->z_all_znodes)) != NULL) {
if ((i++ > nr_to_scan) || (j >= max_array))
break;
ASSERT(list_link_active(&zp->z_link_node));
list_remove(&zfsvfs->z_all_znodes, zp);
list_insert_tail(&zfsvfs->z_all_znodes, zp);
/* Skip active znodes and .zfs entries */
if (MUTEX_HELD(&zp->z_lock) || zp->z_is_ctldir)
continue;
if (igrab(ZTOI(zp)) == NULL)
continue;
zp_array[j] = zp;
j++;
}
mutex_exit(&zfsvfs->z_znodes_lock);
for (i = 0; i < j; i++) {
zp = zp_array[i];
ASSERT3P(zp, !=, NULL);
d_prune_aliases(ZTOI(zp));
if (atomic_read(&ZTOI(zp)->i_count) == 1)
objects++;
zrele(zp);
}
vmem_free(zp_array, max_array * sizeof (znode_t *));
return (objects);
}
/*
* The ARC has requested that the filesystem drop entries from the dentry
* and inode caches. This can occur when the ARC needs to free meta data
* blocks but can't because they are all pinned by entries in these caches.
*/
#if defined(HAVE_SUPER_BLOCK_S_SHRINK)
#define S_SHRINK(sb) (&(sb)->s_shrink)
#elif defined(HAVE_SUPER_BLOCK_S_SHRINK_PTR)
#define S_SHRINK(sb) ((sb)->s_shrink)
#endif
int
zfs_prune(struct super_block *sb, unsigned long nr_to_scan, int *objects)
{
zfsvfs_t *zfsvfs = sb->s_fs_info;
int error = 0;
struct shrinker *shrinker = S_SHRINK(sb);
struct shrink_control sc = {
.nr_to_scan = nr_to_scan,
.gfp_mask = GFP_KERNEL,
};
if ((error = zfs_enter(zfsvfs, FTAG)) != 0)
return (error);
#if defined(HAVE_SPLIT_SHRINKER_CALLBACK) && \
defined(SHRINK_CONTROL_HAS_NID) && \
defined(SHRINKER_NUMA_AWARE)
if (shrinker->flags & SHRINKER_NUMA_AWARE) {
long tc = 1;
for_each_online_node(sc.nid) {
long c = shrinker->count_objects(shrinker, &sc);
if (c == 0 || c == SHRINK_EMPTY)
continue;
tc += c;
}
*objects = 0;
for_each_online_node(sc.nid) {
long c = shrinker->count_objects(shrinker, &sc);
if (c == 0 || c == SHRINK_EMPTY)
continue;
if (c > tc)
tc = c;
sc.nr_to_scan = mult_frac(nr_to_scan, c, tc) + 1;
*objects += (*shrinker->scan_objects)(shrinker, &sc);
}
} else {
*objects = (*shrinker->scan_objects)(shrinker, &sc);
}
#elif defined(HAVE_SPLIT_SHRINKER_CALLBACK)
*objects = (*shrinker->scan_objects)(shrinker, &sc);
#elif defined(HAVE_SINGLE_SHRINKER_CALLBACK)
*objects = (*shrinker->shrink)(shrinker, &sc);
#define D_PRUNE_ALIASES_IS_DEFAULT
*objects = zfs_prune_aliases(zfsvfs, nr_to_scan);
#endif
#ifndef D_PRUNE_ALIASES_IS_DEFAULT
#undef D_PRUNE_ALIASES_IS_DEFAULT
/*
* Fall back to zfs_prune_aliases if the kernel's per-superblock
* shrinker couldn't free anything, possibly due to the inodes being
* allocated in a different memcg.
*/
if (*objects == 0)
*objects = zfs_prune_aliases(zfsvfs, nr_to_scan);
#endif
zfs_exit(zfsvfs, FTAG);
dprintf_ds(zfsvfs->z_os->os_dsl_dataset,
"pruning, nr_to_scan=%lu objects=%d error=%d\n",
nr_to_scan, *objects, error);
return (error);
}
/*
* Teardown the zfsvfs_t.
*
* Note, if 'unmounting' is FALSE, we return with the 'z_teardown_lock'
* and 'z_teardown_inactive_lock' held.
*/
static int
zfsvfs_teardown(zfsvfs_t *zfsvfs, boolean_t unmounting)
{
znode_t *zp;
zfs_unlinked_drain_stop_wait(zfsvfs);
/*
* If someone has not already unmounted this file system,
* drain the zrele_taskq to ensure all active references to the
* zfsvfs_t have been handled only then can it be safely destroyed.
*/
if (zfsvfs->z_os) {
/*
* If we're unmounting we have to wait for the list to
* drain completely.
*
* If we're not unmounting there's no guarantee the list
* will drain completely, but iputs run from the taskq
* may add the parents of dir-based xattrs to the taskq
* so we want to wait for these.
*
* We can safely check z_all_znodes for being empty because the
* VFS has already blocked operations which add to it.
*/
int round = 0;
while (!list_is_empty(&zfsvfs->z_all_znodes)) {
taskq_wait_outstanding(dsl_pool_zrele_taskq(
dmu_objset_pool(zfsvfs->z_os)), 0);
if (++round > 1 && !unmounting)
break;
}
}
ZFS_TEARDOWN_ENTER_WRITE(zfsvfs, FTAG);
if (!unmounting) {
/*
* We purge the parent filesystem's super block as the
* parent filesystem and all of its snapshots have their
* inode's super block set to the parent's filesystem's
* super block. Note, 'z_parent' is self referential
* for non-snapshots.
*/
shrink_dcache_sb(zfsvfs->z_parent->z_sb);
}
/*
* Close the zil. NB: Can't close the zil while zfs_inactive
* threads are blocked as zil_close can call zfs_inactive.
*/
if (zfsvfs->z_log) {
zil_close(zfsvfs->z_log);
zfsvfs->z_log = NULL;
}
rw_enter(&zfsvfs->z_teardown_inactive_lock, RW_WRITER);
/*
* If we are not unmounting (ie: online recv) and someone already
* unmounted this file system while we were doing the switcheroo,
* or a reopen of z_os failed then just bail out now.
*/
if (!unmounting && (zfsvfs->z_unmounted || zfsvfs->z_os == NULL)) {
rw_exit(&zfsvfs->z_teardown_inactive_lock);
ZFS_TEARDOWN_EXIT(zfsvfs, FTAG);
return (SET_ERROR(EIO));
}
/*
* At this point there are no VFS ops active, and any new VFS ops
* will fail with EIO since we have z_teardown_lock for writer (only
* relevant for forced unmount).
*
* Release all holds on dbufs. We also grab an extra reference to all
* the remaining inodes so that the kernel does not attempt to free
* any inodes of a suspended fs. This can cause deadlocks since the
* zfs_resume_fs() process may involve starting threads, which might
* attempt to free unreferenced inodes to free up memory for the new
* thread.
*/
if (!unmounting) {
mutex_enter(&zfsvfs->z_znodes_lock);
for (zp = list_head(&zfsvfs->z_all_znodes); zp != NULL;
zp = list_next(&zfsvfs->z_all_znodes, zp)) {
if (zp->z_sa_hdl)
zfs_znode_dmu_fini(zp);
if (igrab(ZTOI(zp)) != NULL)
zp->z_suspended = B_TRUE;
}
mutex_exit(&zfsvfs->z_znodes_lock);
}
/*
* If we are unmounting, set the unmounted flag and let new VFS ops
* unblock. zfs_inactive will have the unmounted behavior, and all
* other VFS ops will fail with EIO.
*/
if (unmounting) {
zfsvfs->z_unmounted = B_TRUE;
rw_exit(&zfsvfs->z_teardown_inactive_lock);
ZFS_TEARDOWN_EXIT(zfsvfs, FTAG);
}
/*
* z_os will be NULL if there was an error in attempting to reopen
* zfsvfs, so just return as the properties had already been
*
* unregistered and cached data had been evicted before.
*/
if (zfsvfs->z_os == NULL)
return (0);
/*
* Unregister properties.
*/
zfs_unregister_callbacks(zfsvfs);
/*
* Evict cached data. We must write out any dirty data before
* disowning the dataset.
*/
objset_t *os = zfsvfs->z_os;
boolean_t os_dirty = B_FALSE;
for (int t = 0; t < TXG_SIZE; t++) {
if (dmu_objset_is_dirty(os, t)) {
os_dirty = B_TRUE;
break;
}
}
if (!zfs_is_readonly(zfsvfs) && os_dirty) {
txg_wait_synced(dmu_objset_pool(zfsvfs->z_os), 0);
}
dmu_objset_evict_dbufs(zfsvfs->z_os);
dsl_dir_t *dd = os->os_dsl_dataset->ds_dir;
dsl_dir_cancel_waiters(dd);
return (0);
}
#if defined(HAVE_SUPER_SETUP_BDI_NAME)
atomic_long_t zfs_bdi_seq = ATOMIC_LONG_INIT(0);
#endif
int
zfs_domount(struct super_block *sb, zfs_mnt_t *zm, int silent)
{
const char *osname = zm->mnt_osname;
struct inode *root_inode = NULL;
uint64_t recordsize;
int error = 0;
zfsvfs_t *zfsvfs = NULL;
vfs_t *vfs = NULL;
int canwrite;
int dataset_visible_zone;
ASSERT(zm);
ASSERT(osname);
dataset_visible_zone = zone_dataset_visible(osname, &canwrite);
/*
* Refuse to mount a filesystem if we are in a namespace and the
* dataset is not visible or writable in that namespace.
*/
if (!INGLOBALZONE(curproc) &&
(!dataset_visible_zone || !canwrite)) {
return (SET_ERROR(EPERM));
}
error = zfsvfs_parse_options(zm->mnt_data, &vfs);
if (error)
return (error);
/*
* If a non-writable filesystem is being mounted without the
* read-only flag, pretend it was set, as done for snapshots.
*/
if (!canwrite)
vfs->vfs_readonly = B_TRUE;
error = zfsvfs_create(osname, vfs->vfs_readonly, &zfsvfs);
if (error) {
zfsvfs_vfs_free(vfs);
goto out;
}
if ((error = dsl_prop_get_integer(osname, "recordsize",
&recordsize, NULL))) {
zfsvfs_vfs_free(vfs);
goto out;
}
vfs->vfs_data = zfsvfs;
zfsvfs->z_vfs = vfs;
zfsvfs->z_sb = sb;
sb->s_fs_info = zfsvfs;
sb->s_magic = ZFS_SUPER_MAGIC;
sb->s_maxbytes = MAX_LFS_FILESIZE;
sb->s_time_gran = 1;
sb->s_blocksize = recordsize;
sb->s_blocksize_bits = ilog2(recordsize);
error = -zpl_bdi_setup(sb, "zfs");
if (error)
goto out;
sb->s_bdi->ra_pages = 0;
/* Set callback operations for the file system. */
sb->s_op = &zpl_super_operations;
sb->s_xattr = zpl_xattr_handlers;
sb->s_export_op = &zpl_export_operations;
/* Set features for file system. */
zfs_set_fuid_feature(zfsvfs);
if (dmu_objset_is_snapshot(zfsvfs->z_os)) {
uint64_t pval;
atime_changed_cb(zfsvfs, B_FALSE);
readonly_changed_cb(zfsvfs, B_TRUE);
if ((error = dsl_prop_get_integer(osname,
"xattr", &pval, NULL)))
goto out;
xattr_changed_cb(zfsvfs, pval);
if ((error = dsl_prop_get_integer(osname,
"acltype", &pval, NULL)))
goto out;
acltype_changed_cb(zfsvfs, pval);
zfsvfs->z_issnap = B_TRUE;
zfsvfs->z_os->os_sync = ZFS_SYNC_DISABLED;
zfsvfs->z_snap_defer_time = jiffies;
mutex_enter(&zfsvfs->z_os->os_user_ptr_lock);
dmu_objset_set_user(zfsvfs->z_os, zfsvfs);
mutex_exit(&zfsvfs->z_os->os_user_ptr_lock);
} else {
if ((error = zfsvfs_setup(zfsvfs, B_TRUE)))
goto out;
}
/* Allocate a root inode for the filesystem. */
error = zfs_root(zfsvfs, &root_inode);
if (error) {
(void) zfs_umount(sb);
zfsvfs = NULL; /* avoid double-free; first in zfs_umount */
goto out;
}
/* Allocate a root dentry for the filesystem */
sb->s_root = d_make_root(root_inode);
if (sb->s_root == NULL) {
(void) zfs_umount(sb);
zfsvfs = NULL; /* avoid double-free; first in zfs_umount */
error = SET_ERROR(ENOMEM);
goto out;
}
if (!zfsvfs->z_issnap)
zfsctl_create(zfsvfs);
zfsvfs->z_arc_prune = arc_add_prune_callback(zpl_prune_sb, sb);
out:
if (error) {
if (zfsvfs != NULL) {
dmu_objset_disown(zfsvfs->z_os, B_TRUE, zfsvfs);
zfsvfs_free(zfsvfs);
}
/*
* make sure we don't have dangling sb->s_fs_info which
* zfs_preumount will use.
*/
sb->s_fs_info = NULL;
}
return (error);
}
/*
* Called when an unmount is requested and certain sanity checks have
* already passed. At this point no dentries or inodes have been reclaimed
* from their respective caches. We drop the extra reference on the .zfs
* control directory to allow everything to be reclaimed. All snapshots
* must already have been unmounted to reach this point.
*/
void
zfs_preumount(struct super_block *sb)
{
zfsvfs_t *zfsvfs = sb->s_fs_info;
/* zfsvfs is NULL when zfs_domount fails during mount */
if (zfsvfs) {
zfs_unlinked_drain_stop_wait(zfsvfs);
zfsctl_destroy(sb->s_fs_info);
/*
* Wait for zrele_async before entering evict_inodes in
* generic_shutdown_super. The reason we must finish before
* evict_inodes is when lazytime is on, or when zfs_purgedir
* calls zfs_zget, zrele would bump i_count from 0 to 1. This
* would race with the i_count check in evict_inodes. This means
* it could destroy the inode while we are still using it.
*
* We wait for two passes. xattr directories in the first pass
* may add xattr entries in zfs_purgedir, so in the second pass
* we wait for them. We don't use taskq_wait here because it is
* a pool wide taskq. Other mounted filesystems can constantly
* do zrele_async and there's no guarantee when taskq will be
* empty.
*/
taskq_wait_outstanding(dsl_pool_zrele_taskq(
dmu_objset_pool(zfsvfs->z_os)), 0);
taskq_wait_outstanding(dsl_pool_zrele_taskq(
dmu_objset_pool(zfsvfs->z_os)), 0);
}
}
/*
* Called once all other unmount released tear down has occurred.
* It is our responsibility to release any remaining infrastructure.
*/
int
zfs_umount(struct super_block *sb)
{
zfsvfs_t *zfsvfs = sb->s_fs_info;
objset_t *os;
if (zfsvfs->z_arc_prune != NULL)
arc_remove_prune_callback(zfsvfs->z_arc_prune);
VERIFY(zfsvfs_teardown(zfsvfs, B_TRUE) == 0);
os = zfsvfs->z_os;
zpl_bdi_destroy(sb);
/*
* z_os will be NULL if there was an error in
* attempting to reopen zfsvfs.
*/
if (os != NULL) {
/*
* Unset the objset user_ptr.
*/
mutex_enter(&os->os_user_ptr_lock);
dmu_objset_set_user(os, NULL);
mutex_exit(&os->os_user_ptr_lock);
/*
* Finally release the objset
*/
dmu_objset_disown(os, B_TRUE, zfsvfs);
}
zfsvfs_free(zfsvfs);
sb->s_fs_info = NULL;
return (0);
}
int
zfs_remount(struct super_block *sb, int *flags, zfs_mnt_t *zm)
{
zfsvfs_t *zfsvfs = sb->s_fs_info;
vfs_t *vfsp;
boolean_t issnap = dmu_objset_is_snapshot(zfsvfs->z_os);
int error;
if ((issnap || !spa_writeable(dmu_objset_spa(zfsvfs->z_os))) &&
!(*flags & SB_RDONLY)) {
*flags |= SB_RDONLY;
return (EROFS);
}
error = zfsvfs_parse_options(zm->mnt_data, &vfsp);
if (error)
return (error);
if (!zfs_is_readonly(zfsvfs) && (*flags & SB_RDONLY))
txg_wait_synced(dmu_objset_pool(zfsvfs->z_os), 0);
zfs_unregister_callbacks(zfsvfs);
zfsvfs_vfs_free(zfsvfs->z_vfs);
vfsp->vfs_data = zfsvfs;
zfsvfs->z_vfs = vfsp;
if (!issnap)
(void) zfs_register_callbacks(vfsp);
return (error);
}
int
zfs_vget(struct super_block *sb, struct inode **ipp, fid_t *fidp)
{
zfsvfs_t *zfsvfs = sb->s_fs_info;
znode_t *zp;
uint64_t object = 0;
uint64_t fid_gen = 0;
uint64_t gen_mask;
uint64_t zp_gen;
int i, err;
*ipp = NULL;
if (fidp->fid_len == SHORT_FID_LEN || fidp->fid_len == LONG_FID_LEN) {
zfid_short_t *zfid = (zfid_short_t *)fidp;
for (i = 0; i < sizeof (zfid->zf_object); i++)
object |= ((uint64_t)zfid->zf_object[i]) << (8 * i);
for (i = 0; i < sizeof (zfid->zf_gen); i++)
fid_gen |= ((uint64_t)zfid->zf_gen[i]) << (8 * i);
} else {
return (SET_ERROR(EINVAL));
}
/* LONG_FID_LEN means snapdirs */
if (fidp->fid_len == LONG_FID_LEN) {
zfid_long_t *zlfid = (zfid_long_t *)fidp;
uint64_t objsetid = 0;
uint64_t setgen = 0;
for (i = 0; i < sizeof (zlfid->zf_setid); i++)
objsetid |= ((uint64_t)zlfid->zf_setid[i]) << (8 * i);
for (i = 0; i < sizeof (zlfid->zf_setgen); i++)
setgen |= ((uint64_t)zlfid->zf_setgen[i]) << (8 * i);
if (objsetid != ZFSCTL_INO_SNAPDIRS - object) {
dprintf("snapdir fid: objsetid (%llu) != "
"ZFSCTL_INO_SNAPDIRS (%llu) - object (%llu)\n",
objsetid, ZFSCTL_INO_SNAPDIRS, object);
return (SET_ERROR(EINVAL));
}
if (fid_gen > 1 || setgen != 0) {
dprintf("snapdir fid: fid_gen (%llu) and setgen "
"(%llu)\n", fid_gen, setgen);
return (SET_ERROR(EINVAL));
}
return (zfsctl_snapdir_vget(sb, objsetid, fid_gen, ipp));
}
if ((err = zfs_enter(zfsvfs, FTAG)) != 0)
return (err);
/* A zero fid_gen means we are in the .zfs control directories */
if (fid_gen == 0 &&
(object == ZFSCTL_INO_ROOT || object == ZFSCTL_INO_SNAPDIR)) {
*ipp = zfsvfs->z_ctldir;
ASSERT(*ipp != NULL);
if (object == ZFSCTL_INO_SNAPDIR) {
VERIFY(zfsctl_root_lookup(*ipp, "snapshot", ipp,
0, kcred, NULL, NULL) == 0);
} else {
/*
* Must have an existing ref, so igrab()
* cannot return NULL
*/
VERIFY3P(igrab(*ipp), !=, NULL);
}
zfs_exit(zfsvfs, FTAG);
return (0);
}
gen_mask = -1ULL >> (64 - 8 * i);
dprintf("getting %llu [%llu mask %llx]\n", object, fid_gen, gen_mask);
if ((err = zfs_zget(zfsvfs, object, &zp))) {
zfs_exit(zfsvfs, FTAG);
return (err);
}
/* Don't export xattr stuff */
if (zp->z_pflags & ZFS_XATTR) {
zrele(zp);
zfs_exit(zfsvfs, FTAG);
return (SET_ERROR(ENOENT));
}
(void) sa_lookup(zp->z_sa_hdl, SA_ZPL_GEN(zfsvfs), &zp_gen,
sizeof (uint64_t));
zp_gen = zp_gen & gen_mask;
if (zp_gen == 0)
zp_gen = 1;
if ((fid_gen == 0) && (zfsvfs->z_root == object))
fid_gen = zp_gen;
if (zp->z_unlinked || zp_gen != fid_gen) {
dprintf("znode gen (%llu) != fid gen (%llu)\n", zp_gen,
fid_gen);
zrele(zp);
zfs_exit(zfsvfs, FTAG);
return (SET_ERROR(ENOENT));
}
*ipp = ZTOI(zp);
if (*ipp)
zfs_znode_update_vfs(ITOZ(*ipp));
zfs_exit(zfsvfs, FTAG);
return (0);
}
/*
* Block out VFS ops and close zfsvfs_t
*
* Note, if successful, then we return with the 'z_teardown_lock' and
* 'z_teardown_inactive_lock' write held. We leave ownership of the underlying
* dataset and objset intact so that they can be atomically handed off during
* a subsequent rollback or recv operation and the resume thereafter.
*/
int
zfs_suspend_fs(zfsvfs_t *zfsvfs)
{
int error;
if ((error = zfsvfs_teardown(zfsvfs, B_FALSE)) != 0)
return (error);
return (0);
}
/*
* Rebuild SA and release VOPs. Note that ownership of the underlying dataset
* is an invariant across any of the operations that can be performed while the
* filesystem was suspended. Whether it succeeded or failed, the preconditions
* are the same: the relevant objset and associated dataset are owned by
* zfsvfs, held, and long held on entry.
*/
int
zfs_resume_fs(zfsvfs_t *zfsvfs, dsl_dataset_t *ds)
{
int err, err2;
znode_t *zp;
ASSERT(ZFS_TEARDOWN_WRITE_HELD(zfsvfs));
ASSERT(RW_WRITE_HELD(&zfsvfs->z_teardown_inactive_lock));
/*
* We already own this, so just update the objset_t, as the one we
* had before may have been evicted.
*/
objset_t *os;
VERIFY3P(ds->ds_owner, ==, zfsvfs);
VERIFY(dsl_dataset_long_held(ds));
dsl_pool_t *dp = spa_get_dsl(dsl_dataset_get_spa(ds));
dsl_pool_config_enter(dp, FTAG);
VERIFY0(dmu_objset_from_ds(ds, &os));
dsl_pool_config_exit(dp, FTAG);
err = zfsvfs_init(zfsvfs, os);
if (err != 0)
goto bail;
ds->ds_dir->dd_activity_cancelled = B_FALSE;
VERIFY(zfsvfs_setup(zfsvfs, B_FALSE) == 0);
zfs_set_fuid_feature(zfsvfs);
zfsvfs->z_rollback_time = jiffies;
/*
* Attempt to re-establish all the active inodes with their
* dbufs. If a zfs_rezget() fails, then we unhash the inode
* and mark it stale. This prevents a collision if a new
* inode/object is created which must use the same inode
* number. The stale inode will be be released when the
* VFS prunes the dentry holding the remaining references
* on the stale inode.
*/
mutex_enter(&zfsvfs->z_znodes_lock);
for (zp = list_head(&zfsvfs->z_all_znodes); zp;
zp = list_next(&zfsvfs->z_all_znodes, zp)) {
err2 = zfs_rezget(zp);
if (err2) {
zpl_d_drop_aliases(ZTOI(zp));
remove_inode_hash(ZTOI(zp));
}
/* see comment in zfs_suspend_fs() */
if (zp->z_suspended) {
zfs_zrele_async(zp);
zp->z_suspended = B_FALSE;
}
}
mutex_exit(&zfsvfs->z_znodes_lock);
if (!zfs_is_readonly(zfsvfs) && !zfsvfs->z_unmounted) {
/*
* zfs_suspend_fs() could have interrupted freeing
* of dnodes. We need to restart this freeing so
* that we don't "leak" the space.
*/
zfs_unlinked_drain(zfsvfs);
}
/*
* Most of the time zfs_suspend_fs is used for changing the contents
* of the underlying dataset. ZFS rollback and receive operations
* might create files for which negative dentries are present in
* the cache. Since walking the dcache would require a lot of GPL-only
* code duplication, it's much easier on these rather rare occasions
* just to flush the whole dcache for the given dataset/filesystem.
*/
shrink_dcache_sb(zfsvfs->z_sb);
bail:
if (err != 0)
zfsvfs->z_unmounted = B_TRUE;
/* release the VFS ops */
rw_exit(&zfsvfs->z_teardown_inactive_lock);
ZFS_TEARDOWN_EXIT(zfsvfs, FTAG);
if (err != 0) {
/*
* Since we couldn't setup the sa framework, try to force
* unmount this file system.
*/
if (zfsvfs->z_os)
(void) zfs_umount(zfsvfs->z_sb);
}
return (err);
}
/*
* Release VOPs and unmount a suspended filesystem.
*/
int
zfs_end_fs(zfsvfs_t *zfsvfs, dsl_dataset_t *ds)
{
ASSERT(ZFS_TEARDOWN_WRITE_HELD(zfsvfs));
ASSERT(RW_WRITE_HELD(&zfsvfs->z_teardown_inactive_lock));
/*
* We already own this, so just hold and rele it to update the
* objset_t, as the one we had before may have been evicted.
*/
objset_t *os;
VERIFY3P(ds->ds_owner, ==, zfsvfs);
VERIFY(dsl_dataset_long_held(ds));
dsl_pool_t *dp = spa_get_dsl(dsl_dataset_get_spa(ds));
dsl_pool_config_enter(dp, FTAG);
VERIFY0(dmu_objset_from_ds(ds, &os));
dsl_pool_config_exit(dp, FTAG);
zfsvfs->z_os = os;
/* release the VOPs */
rw_exit(&zfsvfs->z_teardown_inactive_lock);
ZFS_TEARDOWN_EXIT(zfsvfs, FTAG);
/*
* Try to force unmount this file system.
*/
(void) zfs_umount(zfsvfs->z_sb);
zfsvfs->z_unmounted = B_TRUE;
return (0);
}
/*
* Automounted snapshots rely on periodic revalidation
* to defer snapshots from being automatically unmounted.
*/
inline void
zfs_exit_fs(zfsvfs_t *zfsvfs)
{
if (!zfsvfs->z_issnap)
return;
if (time_after(jiffies, zfsvfs->z_snap_defer_time +
MAX(zfs_expire_snapshot * HZ / 2, HZ))) {
zfsvfs->z_snap_defer_time = jiffies;
zfsctl_snapshot_unmount_delay(zfsvfs->z_os->os_spa,
dmu_objset_id(zfsvfs->z_os),
zfs_expire_snapshot);
}
}
int
zfs_set_version(zfsvfs_t *zfsvfs, uint64_t newvers)
{
int error;
objset_t *os = zfsvfs->z_os;
dmu_tx_t *tx;
if (newvers < ZPL_VERSION_INITIAL || newvers > ZPL_VERSION)
return (SET_ERROR(EINVAL));
if (newvers < zfsvfs->z_version)
return (SET_ERROR(EINVAL));
if (zfs_spa_version_map(newvers) >
spa_version(dmu_objset_spa(zfsvfs->z_os)))
return (SET_ERROR(ENOTSUP));
tx = dmu_tx_create(os);
dmu_tx_hold_zap(tx, MASTER_NODE_OBJ, B_FALSE, ZPL_VERSION_STR);
if (newvers >= ZPL_VERSION_SA && !zfsvfs->z_use_sa) {
dmu_tx_hold_zap(tx, MASTER_NODE_OBJ, B_TRUE,
ZFS_SA_ATTRS);
dmu_tx_hold_zap(tx, DMU_NEW_OBJECT, FALSE, NULL);
}
error = dmu_tx_assign(tx, TXG_WAIT);
if (error) {
dmu_tx_abort(tx);
return (error);
}
error = zap_update(os, MASTER_NODE_OBJ, ZPL_VERSION_STR,
8, 1, &newvers, tx);
if (error) {
dmu_tx_commit(tx);
return (error);
}
if (newvers >= ZPL_VERSION_SA && !zfsvfs->z_use_sa) {
uint64_t sa_obj;
ASSERT3U(spa_version(dmu_objset_spa(zfsvfs->z_os)), >=,
SPA_VERSION_SA);
sa_obj = zap_create(os, DMU_OT_SA_MASTER_NODE,
DMU_OT_NONE, 0, tx);
error = zap_add(os, MASTER_NODE_OBJ,
ZFS_SA_ATTRS, 8, 1, &sa_obj, tx);
ASSERT0(error);
VERIFY(0 == sa_set_sa_object(os, sa_obj));
sa_register_update_callback(os, zfs_sa_upgrade);
}
spa_history_log_internal_ds(dmu_objset_ds(os), "upgrade", tx,
"from %llu to %llu", zfsvfs->z_version, newvers);
dmu_tx_commit(tx);
zfsvfs->z_version = newvers;
os->os_version = newvers;
zfs_set_fuid_feature(zfsvfs);
return (0);
}
/*
* Return true if the corresponding vfs's unmounted flag is set.
* Otherwise return false.
* If this function returns true we know VFS unmount has been initiated.
*/
boolean_t
zfs_get_vfs_flag_unmounted(objset_t *os)
{
zfsvfs_t *zfvp;
boolean_t unmounted = B_FALSE;
ASSERT(dmu_objset_type(os) == DMU_OST_ZFS);
mutex_enter(&os->os_user_ptr_lock);
zfvp = dmu_objset_get_user(os);
if (zfvp != NULL && zfvp->z_unmounted)
unmounted = B_TRUE;
mutex_exit(&os->os_user_ptr_lock);
return (unmounted);
}
void
zfsvfs_update_fromname(const char *oldname, const char *newname)
{
/*
* We don't need to do anything here, the devname is always current by
* virtue of zfsvfs->z_sb->s_op->show_devname.
*/
(void) oldname, (void) newname;
}
void
zfs_init(void)
{
zfsctl_init();
zfs_znode_init();
dmu_objset_register_type(DMU_OST_ZFS, zpl_get_file_info);
register_filesystem(&zpl_fs_type);
#ifdef HAVE_VFS_FILE_OPERATIONS_EXTEND
register_fo_extend(&zpl_file_operations);
#endif
}
void
zfs_fini(void)
{
/*
* we don't use outstanding because zpl_posix_acl_free might add more.
*/
taskq_wait(system_delay_taskq);
taskq_wait(system_taskq);
#ifdef HAVE_VFS_FILE_OPERATIONS_EXTEND
unregister_fo_extend(&zpl_file_operations);
#endif
unregister_filesystem(&zpl_fs_type);
zfs_znode_fini();
zfsctl_fini();
}
#if defined(_KERNEL)
EXPORT_SYMBOL(zfs_suspend_fs);
EXPORT_SYMBOL(zfs_resume_fs);
EXPORT_SYMBOL(zfs_set_version);
EXPORT_SYMBOL(zfsvfs_create);
EXPORT_SYMBOL(zfsvfs_free);
EXPORT_SYMBOL(zfs_is_readonly);
EXPORT_SYMBOL(zfs_domount);
EXPORT_SYMBOL(zfs_preumount);
EXPORT_SYMBOL(zfs_umount);
EXPORT_SYMBOL(zfs_remount);
EXPORT_SYMBOL(zfs_statvfs);
EXPORT_SYMBOL(zfs_vget);
EXPORT_SYMBOL(zfs_prune);
#endif