LU-10948 llite: Introduce inode open heat counter

[fs/lustre-release.git] / lustre / llite / llite_lib.c

/*
 * GPL HEADER START
 *
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 only,
 * as published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * General Public License version 2 for more details (a copy is included
 * in the LICENSE file that accompanied this code).
 *
 * You should have received a copy of the GNU General Public License
 * version 2 along with this program; If not, see
 * http://www.gnu.org/licenses/gpl-2.0.html
 *
 * GPL HEADER END
 */
/*
 * Copyright (c) 2003, 2010, Oracle and/or its affiliates. All rights reserved.
 * Use is subject to license terms.
 *
 * Copyright (c) 2011, 2017, Intel Corporation.
 */
/*
 * This file is part of Lustre, http://www.lustre.org/
 *
 * lustre/llite/llite_lib.c
 *
 * Lustre Light Super operations
 */

#define DEBUG_SUBSYSTEM S_LLITE

#include <linux/cpu.h>
#include <linux/module.h>
#include <linux/random.h>
#include <linux/statfs.h>
#include <linux/time.h>
#include <linux/types.h>
#include <libcfs/linux/linux-uuid.h>
#include <linux/version.h>
#include <linux/mm.h>
#include <linux/user_namespace.h>
#include <linux/delay.h>
#include <linux/uidgid.h>
#include <linux/security.h>
#include <linux/fs_struct.h>

#ifndef HAVE_CPUS_READ_LOCK
#include <libcfs/linux/linux-cpu.h>
#endif
#include <uapi/linux/lustre/lustre_ioctl.h>
#ifdef HAVE_UAPI_LINUX_MOUNT_H
#include <uapi/linux/mount.h>
#endif

#include <lustre_ha.h>
#include <lustre_dlm.h>
#include <lprocfs_status.h>
#include <lustre_disk.h>
#include <uapi/linux/lustre/lustre_param.h>
#include <lustre_log.h>
#include <cl_object.h>
#include <obd_cksum.h>
#include "llite_internal.h"

struct kmem_cache *ll_file_data_slab;

#ifndef log2
#define log2(n) ffz(~(n))
#endif

/**
 * If there is only one number of core visible to Lustre,
 * async readahead will be disabled, to avoid massive over
 * subscription, we use 1/2 of active cores as default max
 * async readahead requests.
 */
static inline unsigned int ll_get_ra_async_max_active(void)
{
        return cfs_cpt_weight(cfs_cpt_tab, CFS_CPT_ANY) >> 1;
}

static struct ll_sb_info *ll_init_sbi(void)
{
        struct ll_sb_info *sbi = NULL;
        unsigned long pages;
        unsigned long lru_page_max;
        struct sysinfo si;
        int rc;
        int i;

        ENTRY;

        OBD_ALLOC_PTR(sbi);
        if (sbi == NULL)
                RETURN(ERR_PTR(-ENOMEM));

        rc = pcc_super_init(&sbi->ll_pcc_super);
        if (rc < 0)
                GOTO(out_sbi, rc);

        spin_lock_init(&sbi->ll_lock);
        mutex_init(&sbi->ll_lco.lco_lock);
        spin_lock_init(&sbi->ll_pp_extent_lock);
        spin_lock_init(&sbi->ll_process_lock);
        sbi->ll_rw_stats_on = 0;
        sbi->ll_statfs_max_age = OBD_STATFS_CACHE_SECONDS;

        si_meminfo(&si);
        pages = si.totalram - si.totalhigh;
        lru_page_max = pages / 2;

        sbi->ll_ra_info.ra_async_max_active = ll_get_ra_async_max_active();
        sbi->ll_ra_info.ll_readahead_wq =
                cfs_cpt_bind_workqueue("ll-readahead-wq", cfs_cpt_tab,
                                       0, CFS_CPT_ANY,
                                       sbi->ll_ra_info.ra_async_max_active);
        if (IS_ERR(sbi->ll_ra_info.ll_readahead_wq))
                GOTO(out_pcc, rc = PTR_ERR(sbi->ll_ra_info.ll_readahead_wq));

        /* initialize ll_cache data */
        sbi->ll_cache = cl_cache_init(lru_page_max);
        if (sbi->ll_cache == NULL)
                GOTO(out_destroy_ra, rc = -ENOMEM);

        /* initialize foreign symlink prefix path */
        OBD_ALLOC(sbi->ll_foreign_symlink_prefix, sizeof("/mnt/"));
        if (sbi->ll_foreign_symlink_prefix == NULL)
                GOTO(out_destroy_ra, rc = -ENOMEM);
        memcpy(sbi->ll_foreign_symlink_prefix, "/mnt/", sizeof("/mnt/"));
        sbi->ll_foreign_symlink_prefix_size = sizeof("/mnt/");

        /* initialize foreign symlink upcall path, none by default */
        OBD_ALLOC(sbi->ll_foreign_symlink_upcall, sizeof("none"));
        if (sbi->ll_foreign_symlink_upcall == NULL)
                GOTO(out_destroy_ra, rc = -ENOMEM);
        memcpy(sbi->ll_foreign_symlink_upcall, "none", sizeof("none"));
        sbi->ll_foreign_symlink_upcall_items = NULL;
        sbi->ll_foreign_symlink_upcall_nb_items = 0;
        init_rwsem(&sbi->ll_foreign_symlink_sem);
        /* foreign symlink support (LL_SBI_FOREIGN_SYMLINK in ll_flags)
         * not enabled by default
         */

        sbi->ll_ra_info.ra_max_pages =
                min(pages / 32, SBI_DEFAULT_READ_AHEAD_MAX);
        sbi->ll_ra_info.ra_max_pages_per_file =
                min(sbi->ll_ra_info.ra_max_pages / 4,
                    SBI_DEFAULT_READ_AHEAD_PER_FILE_MAX);
        sbi->ll_ra_info.ra_async_pages_per_file_threshold =
                                sbi->ll_ra_info.ra_max_pages_per_file;
        sbi->ll_ra_info.ra_range_pages = SBI_DEFAULT_RA_RANGE_PAGES;
        sbi->ll_ra_info.ra_max_read_ahead_whole_pages = -1;
        atomic_set(&sbi->ll_ra_info.ra_async_inflight, 0);

        sbi->ll_flags |= LL_SBI_VERBOSE;
#ifdef ENABLE_CHECKSUM
        sbi->ll_flags |= LL_SBI_CHECKSUM;
#endif
#ifdef ENABLE_FLOCK
        sbi->ll_flags |= LL_SBI_FLOCK;
#endif

#ifdef HAVE_LRU_RESIZE_SUPPORT
        sbi->ll_flags |= LL_SBI_LRU_RESIZE;
#endif
        sbi->ll_flags |= LL_SBI_LAZYSTATFS;

        for (i = 0; i <= LL_PROCESS_HIST_MAX; i++) {
                spin_lock_init(&sbi->ll_rw_extents_info.pp_extents[i].
                               pp_r_hist.oh_lock);
                spin_lock_init(&sbi->ll_rw_extents_info.pp_extents[i].
                               pp_w_hist.oh_lock);
        }

        /* metadata statahead is enabled by default */
        sbi->ll_sa_running_max = LL_SA_RUNNING_DEF;
        sbi->ll_sa_max = LL_SA_RPC_DEF;
        atomic_set(&sbi->ll_sa_total, 0);
        atomic_set(&sbi->ll_sa_wrong, 0);
        atomic_set(&sbi->ll_sa_running, 0);
        atomic_set(&sbi->ll_agl_total, 0);
        sbi->ll_flags |= LL_SBI_AGL_ENABLED;
        sbi->ll_flags |= LL_SBI_FAST_READ;
        sbi->ll_flags |= LL_SBI_TINY_WRITE;
        ll_sbi_set_encrypt(sbi, true);

        /* root squash */
        sbi->ll_squash.rsi_uid = 0;
        sbi->ll_squash.rsi_gid = 0;
        INIT_LIST_HEAD(&sbi->ll_squash.rsi_nosquash_nids);
        spin_lock_init(&sbi->ll_squash.rsi_lock);

        /* Per-filesystem file heat */
        sbi->ll_heat_decay_weight = SBI_DEFAULT_HEAT_DECAY_WEIGHT;
        sbi->ll_heat_period_second = SBI_DEFAULT_HEAT_PERIOD_SECOND;

        /* Per-fs open heat level before requesting open lock */
        sbi->ll_oc_thrsh_count = SBI_DEFAULT_OPENCACHE_THRESHOLD_COUNT;
        sbi->ll_oc_max_ms = SBI_DEFAULT_OPENCACHE_THRESHOLD_MAX_MS;
        sbi->ll_oc_thrsh_ms = SBI_DEFAULT_OPENCACHE_THRESHOLD_MS;
        RETURN(sbi);
out_destroy_ra:
        if (sbi->ll_foreign_symlink_prefix)
                OBD_FREE(sbi->ll_foreign_symlink_prefix, sizeof("/mnt/"));
        if (sbi->ll_cache) {
                cl_cache_decref(sbi->ll_cache);
                sbi->ll_cache = NULL;
        }
        destroy_workqueue(sbi->ll_ra_info.ll_readahead_wq);
out_pcc:
        pcc_super_fini(&sbi->ll_pcc_super);
out_sbi:
        OBD_FREE_PTR(sbi);
        RETURN(ERR_PTR(rc));
}

static void ll_free_sbi(struct super_block *sb)
{
        struct ll_sb_info *sbi = ll_s2sbi(sb);
        ENTRY;

        if (sbi != NULL) {
                if (!list_empty(&sbi->ll_squash.rsi_nosquash_nids))
                        cfs_free_nidlist(&sbi->ll_squash.rsi_nosquash_nids);
                if (sbi->ll_ra_info.ll_readahead_wq)
                        destroy_workqueue(sbi->ll_ra_info.ll_readahead_wq);
                if (sbi->ll_cache != NULL) {
                        cl_cache_decref(sbi->ll_cache);
                        sbi->ll_cache = NULL;
                }
                if (sbi->ll_foreign_symlink_prefix) {
                        OBD_FREE(sbi->ll_foreign_symlink_prefix,
                                 sbi->ll_foreign_symlink_prefix_size);
                        sbi->ll_foreign_symlink_prefix = NULL;
                }
                if (sbi->ll_foreign_symlink_upcall) {
                        OBD_FREE(sbi->ll_foreign_symlink_upcall,
                                 strlen(sbi->ll_foreign_symlink_upcall) +
                                       1);
                        sbi->ll_foreign_symlink_upcall = NULL;
                }
                if (sbi->ll_foreign_symlink_upcall_items) {
                        int i;
                        int nb_items = sbi->ll_foreign_symlink_upcall_nb_items;
                        struct ll_foreign_symlink_upcall_item *items =
                                sbi->ll_foreign_symlink_upcall_items;

                        for (i = 0 ; i < nb_items; i++)
                                if (items[i].type == STRING_TYPE)
                                        OBD_FREE(items[i].string,
                                                       items[i].size);

                        OBD_FREE_LARGE(items, nb_items *
                                sizeof(struct ll_foreign_symlink_upcall_item));
                        sbi->ll_foreign_symlink_upcall_items = NULL;
                }
                pcc_super_fini(&sbi->ll_pcc_super);
                OBD_FREE(sbi, sizeof(*sbi));
        }
        EXIT;
}

static int client_common_fill_super(struct super_block *sb, char *md, char *dt)
{
        struct inode *root = NULL;
        struct ll_sb_info *sbi = ll_s2sbi(sb);
        struct obd_statfs *osfs = NULL;
        struct ptlrpc_request *request = NULL;
        struct obd_connect_data *data = NULL;
        struct obd_uuid *uuid;
        struct md_op_data *op_data;
        struct lustre_md lmd;
        u64 valid;
        int size, err, checksum;

        ENTRY;
        sbi->ll_md_obd = class_name2obd(md);
        if (!sbi->ll_md_obd) {
                CERROR("MD %s: not setup or attached\n", md);
                RETURN(-EINVAL);
        }

        OBD_ALLOC_PTR(data);
        if (data == NULL)
                RETURN(-ENOMEM);

        OBD_ALLOC_PTR(osfs);
        if (osfs == NULL) {
                OBD_FREE_PTR(data);
                RETURN(-ENOMEM);
        }

        /* pass client page size via ocd_grant_blkbits, the server should report
         * back its backend blocksize for grant calculation purpose */
        data->ocd_grant_blkbits = PAGE_SHIFT;

        /* indicate MDT features supported by this client */
        data->ocd_connect_flags = OBD_CONNECT_IBITS    | OBD_CONNECT_NODEVOH  |
                                  OBD_CONNECT_ATTRFID  | OBD_CONNECT_GRANT |
                                  OBD_CONNECT_VERSION  | OBD_CONNECT_BRW_SIZE |
                                  OBD_CONNECT_SRVLOCK  | OBD_CONNECT_TRUNCLOCK|
                                  OBD_CONNECT_MDS_CAPA | OBD_CONNECT_OSS_CAPA |
                                  OBD_CONNECT_CANCELSET | OBD_CONNECT_FID     |
                                  OBD_CONNECT_AT       | OBD_CONNECT_LOV_V3   |
                                  OBD_CONNECT_VBR | OBD_CONNECT_FULL20 |
                                  OBD_CONNECT_64BITHASH |
                                  OBD_CONNECT_EINPROGRESS |
                                  OBD_CONNECT_JOBSTATS | OBD_CONNECT_LVB_TYPE |
                                  OBD_CONNECT_LAYOUTLOCK | OBD_CONNECT_PINGLESS|
                                  OBD_CONNECT_MAX_EASIZE |
                                  OBD_CONNECT_FLOCK_DEAD |
                                  OBD_CONNECT_DISP_STRIPE | OBD_CONNECT_LFSCK |
                                  OBD_CONNECT_OPEN_BY_FID |
                                  OBD_CONNECT_DIR_STRIPE |
                                  OBD_CONNECT_BULK_MBITS | OBD_CONNECT_CKSUM |
                                  OBD_CONNECT_SUBTREE |
                                  OBD_CONNECT_MULTIMODRPCS |
                                  OBD_CONNECT_GRANT_PARAM |
                                  OBD_CONNECT_SHORTIO | OBD_CONNECT_FLAGS2;

        data->ocd_connect_flags2 = OBD_CONNECT2_DIR_MIGRATE |
                                   OBD_CONNECT2_SUM_STATFS |
                                   OBD_CONNECT2_OVERSTRIPING |
                                   OBD_CONNECT2_FLR |
                                   OBD_CONNECT2_LOCK_CONVERT |
                                   OBD_CONNECT2_ARCHIVE_ID_ARRAY |
                                   OBD_CONNECT2_INC_XID |
                                   OBD_CONNECT2_LSOM |
                                   OBD_CONNECT2_ASYNC_DISCARD |
                                   OBD_CONNECT2_PCC |
                                   OBD_CONNECT2_CRUSH | OBD_CONNECT2_LSEEK |
                                   OBD_CONNECT2_GETATTR_PFID |
                                   OBD_CONNECT2_DOM_LVB;

#ifdef HAVE_LRU_RESIZE_SUPPORT
        if (sbi->ll_flags & LL_SBI_LRU_RESIZE)
                data->ocd_connect_flags |= OBD_CONNECT_LRU_RESIZE;
#endif
        data->ocd_connect_flags |= OBD_CONNECT_ACL_FLAGS;

        data->ocd_cksum_types = obd_cksum_types_supported_client();

        if (OBD_FAIL_CHECK(OBD_FAIL_MDC_LIGHTWEIGHT))
                /* flag mdc connection as lightweight, only used for test
                 * purpose, use with care */
                data->ocd_connect_flags |= OBD_CONNECT_LIGHTWEIGHT;

        data->ocd_ibits_known = MDS_INODELOCK_FULL;
        data->ocd_version = LUSTRE_VERSION_CODE;

        if (sb->s_flags & SB_RDONLY)
                data->ocd_connect_flags |= OBD_CONNECT_RDONLY;
        if (sbi->ll_flags & LL_SBI_USER_XATTR)
                data->ocd_connect_flags |= OBD_CONNECT_XATTR;

#ifdef SB_NOSEC
        /* Setting this indicates we correctly support S_NOSEC (See kernel
         * commit 9e1f1de02c2275d7172e18dc4e7c2065777611bf)
         */
        sb->s_flags |= SB_NOSEC;
#endif
        sbi->ll_fop = ll_select_file_operations(sbi);

        /* always ping even if server suppress_pings */
        if (sbi->ll_flags & LL_SBI_ALWAYS_PING)
                data->ocd_connect_flags &= ~OBD_CONNECT_PINGLESS;

        obd_connect_set_secctx(data);
        if (ll_sbi_has_encrypt(sbi))
                obd_connect_set_enc(data);

#if defined(CONFIG_SECURITY)
        data->ocd_connect_flags2 |= OBD_CONNECT2_SELINUX_POLICY;
#endif

        data->ocd_brw_size = MD_MAX_BRW_SIZE;

        err = obd_connect(NULL, &sbi->ll_md_exp, sbi->ll_md_obd,
                          &sbi->ll_sb_uuid, data, sbi->ll_cache);
        if (err == -EBUSY) {
                LCONSOLE_ERROR_MSG(0x14f, "An MDT (md %s) is performing "
                                   "recovery, of which this client is not a "
                                   "part. Please wait for recovery to complete,"
                                   " abort, or time out.\n", md);
                GOTO(out, err);
        } else if (err) {
                CERROR("cannot connect to %s: rc = %d\n", md, err);
                GOTO(out, err);
        }

        sbi->ll_md_exp->exp_connect_data = *data;

        err = obd_fid_init(sbi->ll_md_exp->exp_obd, sbi->ll_md_exp,
                           LUSTRE_SEQ_METADATA);
        if (err) {
                CERROR("%s: Can't init metadata layer FID infrastructure, "
                       "rc = %d\n", sbi->ll_md_exp->exp_obd->obd_name, err);
                GOTO(out_md, err);
        }

        /* For mount, we only need fs info from MDT0, and also in DNE, it
         * can make sure the client can be mounted as long as MDT0 is
         * avaible */
        err = obd_statfs(NULL, sbi->ll_md_exp, osfs,
                        ktime_get_seconds() - sbi->ll_statfs_max_age,
                        OBD_STATFS_FOR_MDT0);
        if (err)
                GOTO(out_md_fid, err);

        /* This needs to be after statfs to ensure connect has finished.
         * Note that "data" does NOT contain the valid connect reply.
         * If connecting to a 1.8 server there will be no LMV device, so
         * we can access the MDC export directly and exp_connect_flags will
         * be non-zero, but if accessing an upgraded 2.1 server it will
         * have the correct flags filled in.
         * XXX: fill in the LMV exp_connect_flags from MDC(s). */
        valid = exp_connect_flags(sbi->ll_md_exp) & CLIENT_CONNECT_MDT_REQD;
        if (exp_connect_flags(sbi->ll_md_exp) != 0 &&
            valid != CLIENT_CONNECT_MDT_REQD) {
                char *buf;

                OBD_ALLOC_WAIT(buf, PAGE_SIZE);
                obd_connect_flags2str(buf, PAGE_SIZE,
                                      valid ^ CLIENT_CONNECT_MDT_REQD, 0, ",");
                LCONSOLE_ERROR_MSG(0x170, "Server %s does not support "
                                   "feature(s) needed for correct operation "
                                   "of this client (%s). Please upgrade "
                                   "server or downgrade client.\n",
                                   sbi->ll_md_exp->exp_obd->obd_name, buf);
                OBD_FREE(buf, PAGE_SIZE);
                GOTO(out_md_fid, err = -EPROTO);
        }

        size = sizeof(*data);
        err = obd_get_info(NULL, sbi->ll_md_exp, sizeof(KEY_CONN_DATA),
                           KEY_CONN_DATA,  &size, data);
        if (err) {
                CERROR("%s: Get connect data failed: rc = %d\n",
                       sbi->ll_md_exp->exp_obd->obd_name, err);
                GOTO(out_md_fid, err);
        }

        LASSERT(osfs->os_bsize);
        sb->s_blocksize = osfs->os_bsize;
        sb->s_blocksize_bits = log2(osfs->os_bsize);
        sb->s_magic = LL_SUPER_MAGIC;
        sb->s_maxbytes = MAX_LFS_FILESIZE;
        sbi->ll_namelen = osfs->os_namelen;
        sbi->ll_mnt.mnt = current->fs->root.mnt;

        if ((sbi->ll_flags & LL_SBI_USER_XATTR) &&
            !(data->ocd_connect_flags & OBD_CONNECT_XATTR)) {
                LCONSOLE_INFO("Disabling user_xattr feature because "
                              "it is not supported on the server\n");
                sbi->ll_flags &= ~LL_SBI_USER_XATTR;
        }

        if (data->ocd_connect_flags & OBD_CONNECT_ACL) {
#ifdef SB_POSIXACL
                sb->s_flags |= SB_POSIXACL;
#endif
                sbi->ll_flags |= LL_SBI_ACL;
        } else {
                LCONSOLE_INFO("client wants to enable acl, but mdt not!\n");
#ifdef SB_POSIXACL
                sb->s_flags &= ~SB_POSIXACL;
#endif
                sbi->ll_flags &= ~LL_SBI_ACL;
        }

        if (data->ocd_connect_flags & OBD_CONNECT_64BITHASH)
                sbi->ll_flags |= LL_SBI_64BIT_HASH;

        if (data->ocd_connect_flags & OBD_CONNECT_LAYOUTLOCK)
                sbi->ll_flags |= LL_SBI_LAYOUT_LOCK;

        if (obd_connect_has_secctx(data))
                sbi->ll_flags |= LL_SBI_FILE_SECCTX;

        if (ll_sbi_has_encrypt(sbi) && !obd_connect_has_enc(data)) {
                if (ll_sbi_has_test_dummy_encryption(sbi))
                        LCONSOLE_WARN("%s: server %s does not support encryption feature, encryption deactivated.\n",
                                      sbi->ll_fsname,
                                      sbi->ll_md_exp->exp_obd->obd_name);
                ll_sbi_set_encrypt(sbi, false);
        }

        if (data->ocd_ibits_known & MDS_INODELOCK_XATTR) {
                if (!(data->ocd_connect_flags & OBD_CONNECT_MAX_EASIZE)) {
                        LCONSOLE_INFO("%s: disabling xattr cache due to "
                                      "unknown maximum xattr size.\n", dt);
                } else if (!sbi->ll_xattr_cache_set) {
                        /* If xattr_cache is already set (no matter 0 or 1)
                         * during processing llog, it won't be enabled here. */
                        sbi->ll_flags |= LL_SBI_XATTR_CACHE;
                        sbi->ll_xattr_cache_enabled = 1;
                }
        }

        sbi->ll_dt_obd = class_name2obd(dt);
        if (!sbi->ll_dt_obd) {
                CERROR("DT %s: not setup or attached\n", dt);
                GOTO(out_md_fid, err = -ENODEV);
        }

        /* pass client page size via ocd_grant_blkbits, the server should report
         * back its backend blocksize for grant calculation purpose */
        data->ocd_grant_blkbits = PAGE_SHIFT;

        /* indicate OST features supported by this client */
        data->ocd_connect_flags = OBD_CONNECT_GRANT | OBD_CONNECT_VERSION |
                                  OBD_CONNECT_REQPORTAL | OBD_CONNECT_BRW_SIZE |
                                  OBD_CONNECT_CANCELSET | OBD_CONNECT_FID |
                                  OBD_CONNECT_SRVLOCK | OBD_CONNECT_TRUNCLOCK|
                                  OBD_CONNECT_AT | OBD_CONNECT_OSS_CAPA |
                                  OBD_CONNECT_VBR | OBD_CONNECT_FULL20 |
                                  OBD_CONNECT_64BITHASH | OBD_CONNECT_MAXBYTES |
                                  OBD_CONNECT_EINPROGRESS |
                                  OBD_CONNECT_JOBSTATS | OBD_CONNECT_LVB_TYPE |
                                  OBD_CONNECT_LAYOUTLOCK |
                                  OBD_CONNECT_PINGLESS | OBD_CONNECT_LFSCK |
                                  OBD_CONNECT_BULK_MBITS | OBD_CONNECT_SHORTIO |
                                  OBD_CONNECT_FLAGS2 | OBD_CONNECT_GRANT_SHRINK;
        data->ocd_connect_flags2 = OBD_CONNECT2_LOCKAHEAD |
                                   OBD_CONNECT2_INC_XID | OBD_CONNECT2_LSEEK;

        if (!OBD_FAIL_CHECK(OBD_FAIL_OSC_CONNECT_GRANT_PARAM))
                data->ocd_connect_flags |= OBD_CONNECT_GRANT_PARAM;

        /* OBD_CONNECT_CKSUM should always be set, even if checksums are
         * disabled by default, because it can still be enabled on the
         * fly via /sys. As a consequence, we still need to come to an
         * agreement on the supported algorithms at connect time
         */
        data->ocd_connect_flags |= OBD_CONNECT_CKSUM;

        if (OBD_FAIL_CHECK(OBD_FAIL_OSC_CKSUM_ADLER_ONLY))
                data->ocd_cksum_types = OBD_CKSUM_ADLER;
        else
                data->ocd_cksum_types = obd_cksum_types_supported_client();

#ifdef HAVE_LRU_RESIZE_SUPPORT
        data->ocd_connect_flags |= OBD_CONNECT_LRU_RESIZE;
#endif
        /* always ping even if server suppress_pings */
        if (sbi->ll_flags & LL_SBI_ALWAYS_PING)
                data->ocd_connect_flags &= ~OBD_CONNECT_PINGLESS;

        if (ll_sbi_has_encrypt(sbi))
                obd_connect_set_enc(data);

        CDEBUG(D_RPCTRACE, "ocd_connect_flags: %#llx ocd_version: %d "
               "ocd_grant: %d\n", data->ocd_connect_flags,
               data->ocd_version, data->ocd_grant);

        sbi->ll_dt_obd->obd_upcall.onu_owner = &sbi->ll_lco;
        sbi->ll_dt_obd->obd_upcall.onu_upcall = cl_ocd_update;

        data->ocd_brw_size = DT_MAX_BRW_SIZE;

        err = obd_connect(NULL, &sbi->ll_dt_exp, sbi->ll_dt_obd,
                          &sbi->ll_sb_uuid, data, sbi->ll_cache);
        if (err == -EBUSY) {
                LCONSOLE_ERROR_MSG(0x150, "An OST (dt %s) is performing "
                                   "recovery, of which this client is not a "
                                   "part.  Please wait for recovery to "
                                   "complete, abort, or time out.\n", dt);
                GOTO(out_md, err);
        } else if (err) {
                CERROR("%s: Cannot connect to %s: rc = %d\n",
                       sbi->ll_dt_exp->exp_obd->obd_name, dt, err);
                GOTO(out_md, err);
        }

        if (ll_sbi_has_encrypt(sbi) &&
            !obd_connect_has_enc(&sbi->ll_dt_obd->u.lov.lov_ocd)) {
                if (ll_sbi_has_test_dummy_encryption(sbi))
                        LCONSOLE_WARN("%s: server %s does not support encryption feature, encryption deactivated.\n",
                                      sbi->ll_fsname, dt);
                ll_sbi_set_encrypt(sbi, false);
        } else if (ll_sbi_has_test_dummy_encryption(sbi)) {
                LCONSOLE_WARN("Test dummy encryption mode enabled\n");
        }

        sbi->ll_dt_exp->exp_connect_data = *data;

        /* Don't change value if it was specified in the config log */
        if (sbi->ll_ra_info.ra_max_read_ahead_whole_pages == -1) {
                sbi->ll_ra_info.ra_max_read_ahead_whole_pages =
                        max_t(unsigned long, SBI_DEFAULT_READ_AHEAD_WHOLE_MAX,
                              (data->ocd_brw_size >> PAGE_SHIFT));
                if (sbi->ll_ra_info.ra_max_read_ahead_whole_pages >
                    sbi->ll_ra_info.ra_max_pages_per_file)
                        sbi->ll_ra_info.ra_max_read_ahead_whole_pages =
                                sbi->ll_ra_info.ra_max_pages_per_file;
        }

        err = obd_fid_init(sbi->ll_dt_exp->exp_obd, sbi->ll_dt_exp,
                           LUSTRE_SEQ_METADATA);
        if (err) {
                CERROR("%s: Can't init data layer FID infrastructure, "
                       "rc = %d\n", sbi->ll_dt_exp->exp_obd->obd_name, err);
                GOTO(out_dt, err);
        }

        mutex_lock(&sbi->ll_lco.lco_lock);
        sbi->ll_lco.lco_flags = data->ocd_connect_flags;
        sbi->ll_lco.lco_md_exp = sbi->ll_md_exp;
        sbi->ll_lco.lco_dt_exp = sbi->ll_dt_exp;
        mutex_unlock(&sbi->ll_lco.lco_lock);

        fid_zero(&sbi->ll_root_fid);
        err = md_get_root(sbi->ll_md_exp, get_mount_fileset(sb),
                           &sbi->ll_root_fid);
        if (err) {
                CERROR("cannot mds_connect: rc = %d\n", err);
                GOTO(out_lock_cn_cb, err);
        }
        if (!fid_is_sane(&sbi->ll_root_fid)) {
                CERROR("%s: Invalid root fid "DFID" during mount\n",
                       sbi->ll_md_exp->exp_obd->obd_name,
                       PFID(&sbi->ll_root_fid));
                GOTO(out_lock_cn_cb, err = -EINVAL);
        }
        CDEBUG(D_SUPER, "rootfid "DFID"\n", PFID(&sbi->ll_root_fid));

        sb->s_op = &lustre_super_operations;
        sb->s_xattr = ll_xattr_handlers;
#if THREAD_SIZE >= 8192 /*b=17630*/
        sb->s_export_op = &lustre_export_operations;
#endif
#ifdef HAVE_LUSTRE_CRYPTO
        llcrypt_set_ops(sb, &lustre_cryptops);
#endif

        /* make root inode
         * XXX: move this to after cbd setup? */
        valid = OBD_MD_FLGETATTR | OBD_MD_FLBLOCKS | OBD_MD_FLMODEASIZE;
        if (sbi->ll_flags & LL_SBI_ACL)
                valid |= OBD_MD_FLACL;

        OBD_ALLOC_PTR(op_data);
        if (op_data == NULL)
                GOTO(out_lock_cn_cb, err = -ENOMEM);

        op_data->op_fid1 = sbi->ll_root_fid;
        op_data->op_mode = 0;
        op_data->op_valid = valid;

        err = md_getattr(sbi->ll_md_exp, op_data, &request);

        OBD_FREE_PTR(op_data);
        if (err) {
                CERROR("%s: md_getattr failed for root: rc = %d\n",
                       sbi->ll_md_exp->exp_obd->obd_name, err);
                GOTO(out_lock_cn_cb, err);
        }

        err = md_get_lustre_md(sbi->ll_md_exp, request, sbi->ll_dt_exp,
                               sbi->ll_md_exp, &lmd);
        if (err) {
                CERROR("failed to understand root inode md: rc = %d\n", err);
                ptlrpc_req_finished(request);
                GOTO(out_lock_cn_cb, err);
        }

        LASSERT(fid_is_sane(&sbi->ll_root_fid));
        root = ll_iget(sb, cl_fid_build_ino(&sbi->ll_root_fid,
                                            sbi->ll_flags & LL_SBI_32BIT_API),
                       &lmd);
        md_free_lustre_md(sbi->ll_md_exp, &lmd);
        ptlrpc_req_finished(request);

        if (IS_ERR(root)) {
                lmd_clear_acl(&lmd);
                err = IS_ERR(root) ? PTR_ERR(root) : -EBADF;
                root = NULL;
                CERROR("%s: bad ll_iget() for root: rc = %d\n",
                       sbi->ll_fsname, err);
                GOTO(out_root, err);
        }

        checksum = sbi->ll_flags & LL_SBI_CHECKSUM;
        if (sbi->ll_checksum_set) {
                err = obd_set_info_async(NULL, sbi->ll_dt_exp,
                                         sizeof(KEY_CHECKSUM), KEY_CHECKSUM,
                                         sizeof(checksum), &checksum, NULL);
                if (err) {
                        CERROR("%s: Set checksum failed: rc = %d\n",
                               sbi->ll_dt_exp->exp_obd->obd_name, err);
                        GOTO(out_root, err);
                }
        }
        cl_sb_init(sb);

        sb->s_root = d_make_root(root);
        if (sb->s_root == NULL) {
                err = -ENOMEM;
                CERROR("%s: can't make root dentry: rc = %d\n",
                       sbi->ll_fsname, err);
                GOTO(out_root, err);
        }

        sbi->ll_sdev_orig = sb->s_dev;

        /* We set sb->s_dev equal on all lustre clients in order to support
         * NFS export clustering.  NFSD requires that the FSID be the same
         * on all clients. */
        /* s_dev is also used in lt_compare() to compare two fs, but that is
         * only a node-local comparison. */
        uuid = obd_get_uuid(sbi->ll_md_exp);
        if (uuid != NULL)
                sb->s_dev = get_uuid2int(uuid->uuid, strlen(uuid->uuid));

        if (data != NULL)
                OBD_FREE_PTR(data);
        if (osfs != NULL)
                OBD_FREE_PTR(osfs);

        if (sbi->ll_dt_obd) {
                err = sysfs_create_link(&sbi->ll_kset.kobj,
                                        &sbi->ll_dt_obd->obd_kset.kobj,
                                        sbi->ll_dt_obd->obd_type->typ_name);
                if (err < 0) {
                        CERROR("%s: could not register %s in llite: rc = %d\n",
                               dt, sbi->ll_fsname, err);
                        err = 0;
                }
        }

        if (sbi->ll_md_obd) {
                err = sysfs_create_link(&sbi->ll_kset.kobj,
                                        &sbi->ll_md_obd->obd_kset.kobj,
                                        sbi->ll_md_obd->obd_type->typ_name);
                if (err < 0) {
                        CERROR("%s: could not register %s in llite: rc = %d\n",
                               md, sbi->ll_fsname, err);
                        err = 0;
                }
        }

        RETURN(err);
out_root:
        iput(root);
out_lock_cn_cb:
        obd_fid_fini(sbi->ll_dt_exp->exp_obd);
out_dt:
        obd_disconnect(sbi->ll_dt_exp);
        sbi->ll_dt_exp = NULL;
        sbi->ll_dt_obd = NULL;
out_md_fid:
        obd_fid_fini(sbi->ll_md_exp->exp_obd);
out_md:
        obd_disconnect(sbi->ll_md_exp);
        sbi->ll_md_exp = NULL;
        sbi->ll_md_obd = NULL;
out:
        if (data != NULL)
                OBD_FREE_PTR(data);
        if (osfs != NULL)
                OBD_FREE_PTR(osfs);
        return err;
}

int ll_get_max_mdsize(struct ll_sb_info *sbi, int *lmmsize)
{
        int size, rc;

        size = sizeof(*lmmsize);
        rc = obd_get_info(NULL, sbi->ll_dt_exp, sizeof(KEY_MAX_EASIZE),
                          KEY_MAX_EASIZE, &size, lmmsize);
        if (rc != 0) {
                CERROR("%s: cannot get max LOV EA size: rc = %d\n",
                       sbi->ll_dt_exp->exp_obd->obd_name, rc);
                RETURN(rc);
        }

        CDEBUG(D_INFO, "max LOV ea size: %d\n", *lmmsize);

        size = sizeof(int);
        rc = obd_get_info(NULL, sbi->ll_md_exp, sizeof(KEY_MAX_EASIZE),
                          KEY_MAX_EASIZE, &size, lmmsize);
        if (rc)
                CERROR("Get max mdsize error rc %d\n", rc);

        CDEBUG(D_INFO, "max LMV ea size: %d\n", *lmmsize);

        RETURN(rc);
}

/**
 * Get the value of the default_easize parameter.
 *
 * \see client_obd::cl_default_mds_easize
 *
 * \param[in] sbi       superblock info for this filesystem
 * \param[out] lmmsize  pointer to storage location for value
 *
 * \retval 0            on success
 * \retval negative     negated errno on failure
 */
int ll_get_default_mdsize(struct ll_sb_info *sbi, int *lmmsize)
{
        int size, rc;

        size = sizeof(int);
        rc = obd_get_info(NULL, sbi->ll_md_exp, sizeof(KEY_DEFAULT_EASIZE),
                         KEY_DEFAULT_EASIZE, &size, lmmsize);
        if (rc)
                CERROR("Get default mdsize error rc %d\n", rc);

        RETURN(rc);
}

/**
 * Set the default_easize parameter to the given value.
 *
 * \see client_obd::cl_default_mds_easize
 *
 * \param[in] sbi       superblock info for this filesystem
 * \param[in] lmmsize   the size to set
 *
 * \retval 0            on success
 * \retval negative     negated errno on failure
 */
int ll_set_default_mdsize(struct ll_sb_info *sbi, int lmmsize)
{
        int rc;

        if (lmmsize < sizeof(struct lov_mds_md) ||
            lmmsize > OBD_MAX_DEFAULT_EA_SIZE)
                return -EINVAL;

        rc = obd_set_info_async(NULL, sbi->ll_md_exp,
                                sizeof(KEY_DEFAULT_EASIZE), KEY_DEFAULT_EASIZE,
                                sizeof(int), &lmmsize, NULL);

        RETURN(rc);
}

static void client_common_put_super(struct super_block *sb)
{
        struct ll_sb_info *sbi = ll_s2sbi(sb);
        ENTRY;

        cl_sb_fini(sb);

        obd_fid_fini(sbi->ll_dt_exp->exp_obd);
        obd_disconnect(sbi->ll_dt_exp);
        sbi->ll_dt_exp = NULL;

        ll_debugfs_unregister_super(sb);

        obd_fid_fini(sbi->ll_md_exp->exp_obd);
        obd_disconnect(sbi->ll_md_exp);
        sbi->ll_md_exp = NULL;

        EXIT;
}

void ll_kill_super(struct super_block *sb)
{
        struct ll_sb_info *sbi;
        ENTRY;

        /* not init sb ?*/
        if (!(sb->s_flags & SB_ACTIVE))
                return;

        sbi = ll_s2sbi(sb);
        /* we need restore s_dev from changed for clustred NFS before put_super
         * because new kernels have cached s_dev and change sb->s_dev in
         * put_super not affected real removing devices */
        if (sbi) {
                sb->s_dev = sbi->ll_sdev_orig;

                /* wait running statahead threads to quit */
                while (atomic_read(&sbi->ll_sa_running) > 0)
                        schedule_timeout_uninterruptible(
                                cfs_time_seconds(1) >> 3);
        }

        EXIT;
}

static inline int ll_set_opt(const char *opt, char *data, int fl)
{
        if (strncmp(opt, data, strlen(opt)) != 0)
                return 0;
        else
                return fl;
}

/* non-client-specific mount options are parsed in lmd_parse */
static int ll_options(char *options, struct ll_sb_info *sbi)
{
        int tmp;
        char *s1 = options, *s2;
        int *flags = &sbi->ll_flags;
        ENTRY;

        if (!options)
                RETURN(0);

        CDEBUG(D_CONFIG, "Parsing opts %s\n", options);

        while (*s1) {
                CDEBUG(D_SUPER, "next opt=%s\n", s1);
                tmp = ll_set_opt("nolock", s1, LL_SBI_NOLCK);
                if (tmp) {
                        *flags |= tmp;
                        goto next;
                }
                tmp = ll_set_opt("flock", s1, LL_SBI_FLOCK);
                if (tmp) {
                        *flags = (*flags & ~LL_SBI_LOCALFLOCK) | tmp;
                        goto next;
                }
                tmp = ll_set_opt("localflock", s1, LL_SBI_LOCALFLOCK);
                if (tmp) {
                        *flags = (*flags & ~LL_SBI_FLOCK) | tmp;
                        goto next;
                }
                tmp = ll_set_opt("noflock", s1, LL_SBI_FLOCK|LL_SBI_LOCALFLOCK);
                if (tmp) {
                        *flags &= ~tmp;
                        goto next;
                }
                tmp = ll_set_opt("user_xattr", s1, LL_SBI_USER_XATTR);
                if (tmp) {
                        *flags |= tmp;
                        goto next;
                }
                tmp = ll_set_opt("nouser_xattr", s1, LL_SBI_USER_XATTR);
                if (tmp) {
                        *flags &= ~tmp;
                        goto next;
                }
                tmp = ll_set_opt("context", s1, 1);
                if (tmp)
                        goto next;
                tmp = ll_set_opt("fscontext", s1, 1);
                if (tmp)
                        goto next;
                tmp = ll_set_opt("defcontext", s1, 1);
                if (tmp)
                        goto next;
                tmp = ll_set_opt("rootcontext", s1, 1);
                if (tmp)
                        goto next;
                tmp = ll_set_opt("user_fid2path", s1, LL_SBI_USER_FID2PATH);
                if (tmp) {
                        *flags |= tmp;
                        goto next;
                }
                tmp = ll_set_opt("nouser_fid2path", s1, LL_SBI_USER_FID2PATH);
                if (tmp) {
                        *flags &= ~tmp;
                        goto next;
                }

                tmp = ll_set_opt("checksum", s1, LL_SBI_CHECKSUM);
                if (tmp) {
                        *flags |= tmp;
                        sbi->ll_checksum_set = 1;
                        goto next;
                }
                tmp = ll_set_opt("nochecksum", s1, LL_SBI_CHECKSUM);
                if (tmp) {
                        *flags &= ~tmp;
                        sbi->ll_checksum_set = 1;
                        goto next;
                }
                tmp = ll_set_opt("lruresize", s1, LL_SBI_LRU_RESIZE);
                if (tmp) {
                        *flags |= tmp;
                        goto next;
                }
                tmp = ll_set_opt("nolruresize", s1, LL_SBI_LRU_RESIZE);
                if (tmp) {
                        *flags &= ~tmp;
                        goto next;
                }
                tmp = ll_set_opt("lazystatfs", s1, LL_SBI_LAZYSTATFS);
                if (tmp) {
                        *flags |= tmp;
                        goto next;
                }
                tmp = ll_set_opt("nolazystatfs", s1, LL_SBI_LAZYSTATFS);
                if (tmp) {
                        *flags &= ~tmp;
                        goto next;
                }
                tmp = ll_set_opt("32bitapi", s1, LL_SBI_32BIT_API);
                if (tmp) {
                        *flags |= tmp;
                        goto next;
                }
                tmp = ll_set_opt("verbose", s1, LL_SBI_VERBOSE);
                if (tmp) {
                        *flags |= tmp;
                        goto next;
                }
                tmp = ll_set_opt("noverbose", s1, LL_SBI_VERBOSE);
                if (tmp) {
                        *flags &= ~tmp;
                        goto next;
                }
                tmp = ll_set_opt("always_ping", s1, LL_SBI_ALWAYS_PING);
                if (tmp) {
                        *flags |= tmp;
                        goto next;
                }
                tmp = ll_set_opt("test_dummy_encryption", s1,
                                 LL_SBI_TEST_DUMMY_ENCRYPTION);
                if (tmp) {
#ifdef HAVE_LUSTRE_CRYPTO
                        *flags |= tmp;
#else
                        LCONSOLE_WARN("Test dummy encryption mount option ignored: encryption not supported\n");
#endif
                        goto next;
                }
                tmp = ll_set_opt("noencrypt", s1, LL_SBI_ENCRYPT);
                if (tmp) {
#ifdef HAVE_LUSTRE_CRYPTO
                        *flags &= ~tmp;
#else
                        LCONSOLE_WARN("noencrypt mount option ignored: encryption not supported\n");
#endif
                        goto next;
                }
                tmp = ll_set_opt("foreign_symlink", s1, LL_SBI_FOREIGN_SYMLINK);
                if (tmp) {
                        int prefix_pos = sizeof("foreign_symlink=") - 1;
                        int equal_pos = sizeof("foreign_symlink=") - 2;

                        /* non-default prefix provided ? */
                        if (strlen(s1) >= sizeof("foreign_symlink=") &&
                            *(s1 + equal_pos) == '=') {
                                char *old = sbi->ll_foreign_symlink_prefix;
                                size_t old_len =
                                        sbi->ll_foreign_symlink_prefix_size;

                                /* path must be absolute */
                                if (*(s1 + sizeof("foreign_symlink=")
                                      - 1) != '/') {
                                        LCONSOLE_ERROR_MSG(0x152,
                                                "foreign prefix '%s' must be an absolute path\n",
                                                s1 + prefix_pos);
                                        RETURN(-EINVAL);
                                }
                                /* last option ? */
                                s2 = strchrnul(s1 + prefix_pos, ',');

                                if (sbi->ll_foreign_symlink_prefix) {
                                        sbi->ll_foreign_symlink_prefix = NULL;
                                        sbi->ll_foreign_symlink_prefix_size = 0;
                                }
                                /* alloc for path length and '\0' */
                                OBD_ALLOC(sbi->ll_foreign_symlink_prefix,
                                                s2 - (s1 + prefix_pos) + 1);
                                if (!sbi->ll_foreign_symlink_prefix) {
                                        /* restore previous */
                                        sbi->ll_foreign_symlink_prefix = old;
                                        sbi->ll_foreign_symlink_prefix_size =
                                                old_len;
                                        RETURN(-ENOMEM);
                                }
                                if (old)
                                        OBD_FREE(old, old_len);
                                strncpy(sbi->ll_foreign_symlink_prefix,
                                        s1 + prefix_pos,
                                        s2 - (s1 + prefix_pos));
                                sbi->ll_foreign_symlink_prefix_size =
                                        s2 - (s1 + prefix_pos) + 1;
                        } else {
                                LCONSOLE_ERROR_MSG(0x152,
                                                   "invalid %s option\n", s1);
                        }
                        /* enable foreign symlink support */
                        *flags |= tmp;
                        goto next;
                }
                LCONSOLE_ERROR_MSG(0x152, "Unknown option '%s', won't mount.\n",
                                   s1);
                RETURN(-EINVAL);

next:
                /* Find next opt */
                s2 = strchr(s1, ',');
                if (s2 == NULL)
                        break;
                s1 = s2 + 1;
        }
        RETURN(0);
}

void ll_lli_init(struct ll_inode_info *lli)
{
        lli->lli_inode_magic = LLI_INODE_MAGIC;
        lli->lli_flags = 0;
        spin_lock_init(&lli->lli_lock);
        lli->lli_posix_acl = NULL;
        /* Do not set lli_fid, it has been initialized already. */
        fid_zero(&lli->lli_pfid);
        lli->lli_mds_read_och = NULL;
        lli->lli_mds_write_och = NULL;
        lli->lli_mds_exec_och = NULL;
        lli->lli_open_fd_read_count = 0;
        lli->lli_open_fd_write_count = 0;
        lli->lli_open_fd_exec_count = 0;
        mutex_init(&lli->lli_och_mutex);
        spin_lock_init(&lli->lli_agl_lock);
        spin_lock_init(&lli->lli_layout_lock);
        ll_layout_version_set(lli, CL_LAYOUT_GEN_NONE);
        lli->lli_clob = NULL;

        init_rwsem(&lli->lli_xattrs_list_rwsem);
        mutex_init(&lli->lli_xattrs_enq_lock);

        LASSERT(lli->lli_vfs_inode.i_mode != 0);
        if (S_ISDIR(lli->lli_vfs_inode.i_mode)) {
                lli->lli_opendir_key = NULL;
                lli->lli_sai = NULL;
                spin_lock_init(&lli->lli_sa_lock);
                lli->lli_opendir_pid = 0;
                lli->lli_sa_enabled = 0;
                init_rwsem(&lli->lli_lsm_sem);
        } else {
                mutex_init(&lli->lli_size_mutex);
                mutex_init(&lli->lli_setattr_mutex);
                lli->lli_symlink_name = NULL;
                ll_trunc_sem_init(&lli->lli_trunc_sem);
                range_lock_tree_init(&lli->lli_write_tree);
                init_rwsem(&lli->lli_glimpse_sem);
                lli->lli_glimpse_time = ktime_set(0, 0);
                INIT_LIST_HEAD(&lli->lli_agl_list);
                lli->lli_agl_index = 0;
                lli->lli_async_rc = 0;
                spin_lock_init(&lli->lli_heat_lock);
                obd_heat_clear(lli->lli_heat_instances, OBD_HEAT_COUNT);
                lli->lli_heat_flags = 0;
                mutex_init(&lli->lli_pcc_lock);
                lli->lli_pcc_state = PCC_STATE_FL_NONE;
                lli->lli_pcc_inode = NULL;
                lli->lli_pcc_dsflags = PCC_DATASET_INVALID;
                lli->lli_pcc_generation = 0;
                mutex_init(&lli->lli_group_mutex);
                lli->lli_group_users = 0;
                lli->lli_group_gid = 0;
        }
        mutex_init(&lli->lli_layout_mutex);
        memset(lli->lli_jobid, 0, sizeof(lli->lli_jobid));
}

#define MAX_STRING_SIZE 128

#ifndef HAVE_SUPER_SETUP_BDI_NAME

#define LSI_BDI_INITIALIZED     0x00400000

#ifndef HAVE_BDI_CAP_MAP_COPY
# define BDI_CAP_MAP_COPY       0
#endif

static int super_setup_bdi_name(struct super_block *sb, char *fmt, ...)
{
        struct  lustre_sb_info *lsi = s2lsi(sb);
        char buf[MAX_STRING_SIZE];
        va_list args;
        int err;

        err = bdi_init(&lsi->lsi_bdi);
        if (err)
                return err;

        lsi->lsi_flags |= LSI_BDI_INITIALIZED;
        lsi->lsi_bdi.capabilities = BDI_CAP_MAP_COPY;
        lsi->lsi_bdi.name = "lustre";
        va_start(args, fmt);
        vsnprintf(buf, MAX_STRING_SIZE, fmt, args);
        va_end(args);
        err = bdi_register(&lsi->lsi_bdi, NULL, "%s", buf);
        va_end(args);
        if (!err)
                sb->s_bdi = &lsi->lsi_bdi;

        return err;
}
#endif /* !HAVE_SUPER_SETUP_BDI_NAME */

int ll_fill_super(struct super_block *sb)
{
        struct  lustre_profile *lprof = NULL;
        struct  lustre_sb_info *lsi = s2lsi(sb);
        struct  ll_sb_info *sbi = NULL;
        char    *dt = NULL, *md = NULL;
        char    *profilenm = get_profile_name(sb);
        struct config_llog_instance *cfg;
        /* %p for void* in printf needs 16+2 characters: 0xffffffffffffffff */
        const int instlen = LUSTRE_MAXINSTANCE + 2;
        unsigned long cfg_instance = ll_get_cfg_instance(sb);
        char name[MAX_STRING_SIZE];
        int md_len = 0;
        int dt_len = 0;
        uuid_t uuid;
        char *ptr;
        int len;
        int err;

        ENTRY;
        /* for ASLR, to map between cfg_instance and hashed ptr */
        CDEBUG(D_VFSTRACE, "VFS Op: cfg_instance %s-%016lx (sb %p)\n",
               profilenm, cfg_instance, sb);

        OBD_RACE(OBD_FAIL_LLITE_RACE_MOUNT);

        OBD_ALLOC_PTR(cfg);
        if (cfg == NULL)
                GOTO(out_free_cfg, err = -ENOMEM);

        /* client additional sb info */
        lsi->lsi_llsbi = sbi = ll_init_sbi();
        if (IS_ERR(sbi))
                GOTO(out_free_cfg, err = PTR_ERR(sbi));

        err = ll_options(lsi->lsi_lmd->lmd_opts, sbi);
        if (err)
                GOTO(out_free_cfg, err);

        /* kernel >= 2.6.38 store dentry operations in sb->s_d_op. */
        sb->s_d_op = &ll_d_ops;

        /* UUID handling */
        generate_random_uuid(uuid.b);
        snprintf(sbi->ll_sb_uuid.uuid, sizeof(sbi->ll_sb_uuid), "%pU", uuid.b);

        CDEBUG(D_CONFIG, "llite sb uuid: %s\n", sbi->ll_sb_uuid.uuid);

        /* Get fsname */
        len = strlen(profilenm);
        ptr = strrchr(profilenm, '-');
        if (ptr && (strcmp(ptr, "-client") == 0))
                len -= 7;

        if (len > LUSTRE_MAXFSNAME) {
                if (unlikely(len >= MAX_STRING_SIZE))
                        len = MAX_STRING_SIZE - 1;
                strncpy(name, profilenm, len);
                name[len] = '\0';
                err = -ENAMETOOLONG;
                CERROR("%s: fsname longer than %u characters: rc = %d\n",
                       name, LUSTRE_MAXFSNAME, err);
                GOTO(out_free_cfg, err);
        }
        strncpy(sbi->ll_fsname, profilenm, len);
        sbi->ll_fsname[len] = '\0';

        /* Mount info */
        snprintf(name, sizeof(name), "%.*s-%016lx", len,
                 profilenm, cfg_instance);

        err = super_setup_bdi_name(sb, "%s", name);
        if (err)
                GOTO(out_free_cfg, err);

        /* Call ll_debugfs_register_super() before lustre_process_log()
         * so that "llite.*.*" params can be processed correctly.
         */
        err = ll_debugfs_register_super(sb, name);
        if (err < 0) {
                CERROR("%s: could not register mountpoint in llite: rc = %d\n",
                       sbi->ll_fsname, err);
                err = 0;
        }

        /* The cfg_instance is a value unique to this super, in case some
         * joker tries to mount the same fs at two mount points.
         */
        cfg->cfg_instance = cfg_instance;
        cfg->cfg_uuid = lsi->lsi_llsbi->ll_sb_uuid;
        cfg->cfg_callback = class_config_llog_handler;
        cfg->cfg_sub_clds = CONFIG_SUB_CLIENT;
        /* set up client obds */
        err = lustre_process_log(sb, profilenm, cfg);
        if (err < 0)
                GOTO(out_debugfs, err);

        /* Profile set with LCFG_MOUNTOPT so we can find our mdc and osc obds */
        lprof = class_get_profile(profilenm);
        if (lprof == NULL) {
                LCONSOLE_ERROR_MSG(0x156, "The client profile '%s' could not be"
                                   " read from the MGS.  Does that filesystem "
                                   "exist?\n", profilenm);
                GOTO(out_debugfs, err = -EINVAL);
        }
        CDEBUG(D_CONFIG, "Found profile %s: mdc=%s osc=%s\n", profilenm,
               lprof->lp_md, lprof->lp_dt);

        dt_len = strlen(lprof->lp_dt) + instlen + 2;
        OBD_ALLOC(dt, dt_len);
        if (!dt)
                GOTO(out_profile, err = -ENOMEM);
        snprintf(dt, dt_len - 1, "%s-%016lx", lprof->lp_dt, cfg_instance);

        md_len = strlen(lprof->lp_md) + instlen + 2;
        OBD_ALLOC(md, md_len);
        if (!md)
                GOTO(out_free_dt, err = -ENOMEM);
        snprintf(md, md_len - 1, "%s-%016lx", lprof->lp_md, cfg_instance);

        /* connections, registrations, sb setup */
        err = client_common_fill_super(sb, md, dt);
        if (err < 0)
                GOTO(out_free_md, err);

        sbi->ll_client_common_fill_super_succeeded = 1;

out_free_md:
        if (md)
                OBD_FREE(md, md_len);
out_free_dt:
        if (dt)
                OBD_FREE(dt, dt_len);
out_profile:
        if (lprof)
                class_put_profile(lprof);
out_debugfs:
        if (err < 0)
                ll_debugfs_unregister_super(sb);
out_free_cfg:
        if (cfg)
                OBD_FREE_PTR(cfg);

        if (err)
                ll_put_super(sb);
        else if (sbi->ll_flags & LL_SBI_VERBOSE)
                LCONSOLE_WARN("Mounted %s\n", profilenm);
        RETURN(err);
} /* ll_fill_super */

void ll_put_super(struct super_block *sb)
{
        struct config_llog_instance cfg, params_cfg;
        struct obd_device *obd;
        struct lustre_sb_info *lsi = s2lsi(sb);
        struct ll_sb_info *sbi = ll_s2sbi(sb);
        char *profilenm = get_profile_name(sb);
        unsigned long cfg_instance = ll_get_cfg_instance(sb);
        long ccc_count;
        int next, force = 1, rc = 0;
        ENTRY;

        if (IS_ERR(sbi))
                GOTO(out_no_sbi, 0);

        /* Should replace instance_id with something better for ASLR */
        CDEBUG(D_VFSTRACE, "VFS Op: cfg_instance %s-%016lx (sb %p)\n",
               profilenm, cfg_instance, sb);

        cfg.cfg_instance = cfg_instance;
        lustre_end_log(sb, profilenm, &cfg);

        params_cfg.cfg_instance = cfg_instance;
        lustre_end_log(sb, PARAMS_FILENAME, &params_cfg);

        if (sbi->ll_md_exp) {
                obd = class_exp2obd(sbi->ll_md_exp);
                if (obd)
                        force = obd->obd_force;
        }

        /* Wait for unstable pages to be committed to stable storage */
        if (force == 0) {
                rc = l_wait_event_abortable(
                        sbi->ll_cache->ccc_unstable_waitq,
                        atomic_long_read(&sbi->ll_cache->ccc_unstable_nr) == 0);
        }

        ccc_count = atomic_long_read(&sbi->ll_cache->ccc_unstable_nr);
        if (force == 0 && rc != -ERESTARTSYS)
                LASSERTF(ccc_count == 0, "count: %li\n", ccc_count);

        /* We need to set force before the lov_disconnect in
         * lustre_common_put_super, since l_d cleans up osc's as well.
         */
        if (force) {
                next = 0;
                while ((obd = class_devices_in_group(&sbi->ll_sb_uuid,
                                                     &next)) != NULL) {
                        obd->obd_force = force;
                }
        }

        if (sbi->ll_client_common_fill_super_succeeded) {
                /* Only if client_common_fill_super succeeded */
                client_common_put_super(sb);
        }

        next = 0;
        while ((obd = class_devices_in_group(&sbi->ll_sb_uuid, &next)))
                class_manual_cleanup(obd);

        if (sbi->ll_flags & LL_SBI_VERBOSE)
                LCONSOLE_WARN("Unmounted %s\n", profilenm ? profilenm : "");

        if (profilenm)
                class_del_profile(profilenm);

#ifndef HAVE_SUPER_SETUP_BDI_NAME
        if (lsi->lsi_flags & LSI_BDI_INITIALIZED) {
                bdi_destroy(&lsi->lsi_bdi);
                lsi->lsi_flags &= ~LSI_BDI_INITIALIZED;
        }
#endif

        ll_free_sbi(sb);
        lsi->lsi_llsbi = NULL;
out_no_sbi:
        lustre_common_put_super(sb);

        cl_env_cache_purge(~0);

        EXIT;
} /* client_put_super */

struct inode *ll_inode_from_resource_lock(struct ldlm_lock *lock)
{
        struct inode *inode = NULL;

        /* NOTE: we depend on atomic igrab() -bzzz */
        lock_res_and_lock(lock);
        if (lock->l_resource->lr_lvb_inode) {
                struct ll_inode_info * lli;
                lli = ll_i2info(lock->l_resource->lr_lvb_inode);
                if (lli->lli_inode_magic == LLI_INODE_MAGIC) {
                        inode = igrab(lock->l_resource->lr_lvb_inode);
                } else {
                        inode = lock->l_resource->lr_lvb_inode;
                        LDLM_DEBUG_LIMIT(inode->i_state & I_FREEING ?  D_INFO :
                                         D_WARNING, lock, "lr_lvb_inode %p is "
                                         "bogus: magic %08x",
                                         lock->l_resource->lr_lvb_inode,
                                         lli->lli_inode_magic);
                        inode = NULL;
                }
        }
        unlock_res_and_lock(lock);
        return inode;
}

void ll_dir_clear_lsm_md(struct inode *inode)
{
        struct ll_inode_info *lli = ll_i2info(inode);

        LASSERT(S_ISDIR(inode->i_mode));

        if (lli->lli_lsm_md) {
                lmv_free_memmd(lli->lli_lsm_md);
                lli->lli_lsm_md = NULL;
        }

        if (lli->lli_default_lsm_md) {
                lmv_free_memmd(lli->lli_default_lsm_md);
                lli->lli_default_lsm_md = NULL;
        }
}

static struct inode *ll_iget_anon_dir(struct super_block *sb,
                                      const struct lu_fid *fid,
                                      struct lustre_md *md)
{
        struct ll_sb_info       *sbi = ll_s2sbi(sb);
        struct mdt_body         *body = md->body;
        struct inode            *inode;
        ino_t                   ino;
        ENTRY;

        ino = cl_fid_build_ino(fid, sbi->ll_flags & LL_SBI_32BIT_API);
        inode = iget_locked(sb, ino);
        if (inode == NULL) {
                CERROR("%s: failed get simple inode "DFID": rc = -ENOENT\n",
                       sbi->ll_fsname, PFID(fid));
                RETURN(ERR_PTR(-ENOENT));
        }

        if (inode->i_state & I_NEW) {
                struct ll_inode_info *lli = ll_i2info(inode);
                struct lmv_stripe_md *lsm = md->lmv;

                inode->i_mode = (inode->i_mode & ~S_IFMT) |
                                (body->mbo_mode & S_IFMT);
                LASSERTF(S_ISDIR(inode->i_mode), "Not slave inode "DFID"\n",
                         PFID(fid));

                inode->i_mtime.tv_sec = 0;
                inode->i_atime.tv_sec = 0;
                inode->i_ctime.tv_sec = 0;
                inode->i_rdev = 0;

#ifdef HAVE_BACKING_DEV_INFO
                /* initializing backing dev info. */
                inode->i_mapping->backing_dev_info =
                                                &s2lsi(inode->i_sb)->lsi_bdi;
#endif
                inode->i_op = &ll_dir_inode_operations;
                inode->i_fop = &ll_dir_operations;
                lli->lli_fid = *fid;
                ll_lli_init(lli);

                LASSERT(lsm != NULL);
                /* master object FID */
                lli->lli_pfid = body->mbo_fid1;
                CDEBUG(D_INODE, "lli %p slave "DFID" master "DFID"\n",
                       lli, PFID(fid), PFID(&lli->lli_pfid));
                unlock_new_inode(inode);
        }

        RETURN(inode);
}

static int ll_init_lsm_md(struct inode *inode, struct lustre_md *md)
{
        struct lu_fid *fid;
        struct lmv_stripe_md *lsm = md->lmv;
        struct ll_inode_info *lli = ll_i2info(inode);
        int i;

        LASSERT(lsm != NULL);

        CDEBUG(D_INODE, "%s: "DFID" set dir layout:\n",
               ll_i2sbi(inode)->ll_fsname, PFID(&lli->lli_fid));
        lsm_md_dump(D_INODE, lsm);

        if (!lmv_dir_striped(lsm))
                goto out;

        /* XXX sigh, this lsm_root initialization should be in
         * LMV layer, but it needs ll_iget right now, so we
         * put this here right now. */
        for (i = 0; i < lsm->lsm_md_stripe_count; i++) {
                fid = &lsm->lsm_md_oinfo[i].lmo_fid;
                LASSERT(lsm->lsm_md_oinfo[i].lmo_root == NULL);

                if (!fid_is_sane(fid))
                        continue;

                /* Unfortunately ll_iget will call ll_update_inode,
                 * where the initialization of slave inode is slightly
                 * different, so it reset lsm_md to NULL to avoid
                 * initializing lsm for slave inode. */
                lsm->lsm_md_oinfo[i].lmo_root =
                                ll_iget_anon_dir(inode->i_sb, fid, md);
                if (IS_ERR(lsm->lsm_md_oinfo[i].lmo_root)) {
                        int rc = PTR_ERR(lsm->lsm_md_oinfo[i].lmo_root);

                        lsm->lsm_md_oinfo[i].lmo_root = NULL;
                        while (i-- > 0) {
                                iput(lsm->lsm_md_oinfo[i].lmo_root);
                                lsm->lsm_md_oinfo[i].lmo_root = NULL;
                        }
                        return rc;
                }
        }
out:
        lli->lli_lsm_md = lsm;

        return 0;
}

static void ll_update_default_lsm_md(struct inode *inode, struct lustre_md *md)
{
        struct ll_inode_info *lli = ll_i2info(inode);

        if (!md->default_lmv) {
                /* clear default lsm */
                if (lli->lli_default_lsm_md) {
                        down_write(&lli->lli_lsm_sem);
                        if (lli->lli_default_lsm_md) {
                                lmv_free_memmd(lli->lli_default_lsm_md);
                                lli->lli_default_lsm_md = NULL;
                        }
                        up_write(&lli->lli_lsm_sem);
                }
        } else if (lli->lli_default_lsm_md) {
                /* update default lsm if it changes */
                down_read(&lli->lli_lsm_sem);
                if (lli->lli_default_lsm_md &&
                    !lsm_md_eq(lli->lli_default_lsm_md, md->default_lmv)) {
                        up_read(&lli->lli_lsm_sem);
                        down_write(&lli->lli_lsm_sem);
                        if (lli->lli_default_lsm_md)
                                lmv_free_memmd(lli->lli_default_lsm_md);
                        lli->lli_default_lsm_md = md->default_lmv;
                        lsm_md_dump(D_INODE, md->default_lmv);
                        md->default_lmv = NULL;
                        up_write(&lli->lli_lsm_sem);
                } else {
                        up_read(&lli->lli_lsm_sem);
                }
        } else {
                /* init default lsm */
                down_write(&lli->lli_lsm_sem);
                lli->lli_default_lsm_md = md->default_lmv;
                lsm_md_dump(D_INODE, md->default_lmv);
                md->default_lmv = NULL;
                up_write(&lli->lli_lsm_sem);
        }
}

static int ll_update_lsm_md(struct inode *inode, struct lustre_md *md)
{
        struct ll_inode_info *lli = ll_i2info(inode);
        struct lmv_stripe_md *lsm = md->lmv;
        struct cl_attr  *attr;
        int rc = 0;

        ENTRY;

        LASSERT(S_ISDIR(inode->i_mode));
        CDEBUG(D_INODE, "update lsm %p of "DFID"\n", lli->lli_lsm_md,
               PFID(ll_inode2fid(inode)));

        /* update default LMV */
        if (md->default_lmv)
                ll_update_default_lsm_md(inode, md);

        /*
         * no striped information from request, lustre_md from req does not
         * include stripeEA, see ll_md_setattr()
         */
        if (!lsm)
                RETURN(0);

        /*
         * normally dir layout doesn't change, only take read lock to check
         * that to avoid blocking other MD operations.
         */
        down_read(&lli->lli_lsm_sem);

        /* some current lookup initialized lsm, and unchanged */
        if (lli->lli_lsm_md && lsm_md_eq(lli->lli_lsm_md, lsm))
                GOTO(unlock, rc = 0);

        /* if dir layout doesn't match, check whether version is increased,
         * which means layout is changed, this happens in dir split/merge and
         * lfsck.
         *
         * foreign LMV should not change.
         */
        if (lli->lli_lsm_md && lmv_dir_striped(lli->lli_lsm_md) &&
            lsm->lsm_md_layout_version <=
            lli->lli_lsm_md->lsm_md_layout_version) {
                CERROR("%s: "DFID" dir layout mismatch:\n",
                       ll_i2sbi(inode)->ll_fsname, PFID(&lli->lli_fid));
                lsm_md_dump(D_ERROR, lli->lli_lsm_md);
                lsm_md_dump(D_ERROR, lsm);
                GOTO(unlock, rc = -EINVAL);
        }

        up_read(&lli->lli_lsm_sem);
        down_write(&lli->lli_lsm_sem);
        /* clear existing lsm */
        if (lli->lli_lsm_md) {
                lmv_free_memmd(lli->lli_lsm_md);
                lli->lli_lsm_md = NULL;
        }

        rc = ll_init_lsm_md(inode, md);
        up_write(&lli->lli_lsm_sem);

        if (rc)
                RETURN(rc);

        /* set md->lmv to NULL, so the following free lustre_md will not free
         * this lsm.
         */
        md->lmv = NULL;

        /* md_merge_attr() may take long, since lsm is already set, switch to
         * read lock.
         */
        down_read(&lli->lli_lsm_sem);

        if (!lmv_dir_striped(lli->lli_lsm_md))
                GOTO(unlock, rc = 0);

        OBD_ALLOC_PTR(attr);
        if (!attr)
                GOTO(unlock, rc = -ENOMEM);

        /* validate the lsm */
        rc = md_merge_attr(ll_i2mdexp(inode), lli->lli_lsm_md, attr,
                           ll_md_blocking_ast);
        if (!rc) {
                if (md->body->mbo_valid & OBD_MD_FLNLINK)
                        md->body->mbo_nlink = attr->cat_nlink;
                if (md->body->mbo_valid & OBD_MD_FLSIZE)
                        md->body->mbo_size = attr->cat_size;
                if (md->body->mbo_valid & OBD_MD_FLATIME)
                        md->body->mbo_atime = attr->cat_atime;
                if (md->body->mbo_valid & OBD_MD_FLCTIME)
                        md->body->mbo_ctime = attr->cat_ctime;
                if (md->body->mbo_valid & OBD_MD_FLMTIME)
                        md->body->mbo_mtime = attr->cat_mtime;
        }

        OBD_FREE_PTR(attr);
        GOTO(unlock, rc);
unlock:
        up_read(&lli->lli_lsm_sem);

        return rc;
}

void ll_clear_inode(struct inode *inode)
{
        struct ll_inode_info *lli = ll_i2info(inode);
        struct ll_sb_info *sbi = ll_i2sbi(inode);

        ENTRY;

        CDEBUG(D_VFSTRACE, "VFS Op:inode="DFID"(%p)\n",
               PFID(ll_inode2fid(inode)), inode);

        if (S_ISDIR(inode->i_mode)) {
                /* these should have been cleared in ll_file_release */
                LASSERT(lli->lli_opendir_key == NULL);
                LASSERT(lli->lli_sai == NULL);
                LASSERT(lli->lli_opendir_pid == 0);
        } else {
                pcc_inode_free(inode);
        }

        md_null_inode(sbi->ll_md_exp, ll_inode2fid(inode));

        LASSERT(!lli->lli_open_fd_write_count);
        LASSERT(!lli->lli_open_fd_read_count);
        LASSERT(!lli->lli_open_fd_exec_count);

        if (lli->lli_mds_write_och)
                ll_md_real_close(inode, FMODE_WRITE);
        if (lli->lli_mds_exec_och)
                ll_md_real_close(inode, FMODE_EXEC);
        if (lli->lli_mds_read_och)
                ll_md_real_close(inode, FMODE_READ);

        if (S_ISLNK(inode->i_mode) && lli->lli_symlink_name) {
                OBD_FREE(lli->lli_symlink_name,
                         strlen(lli->lli_symlink_name) + 1);
                lli->lli_symlink_name = NULL;
        }

        ll_xattr_cache_destroy(inode);

        forget_all_cached_acls(inode);
        lli_clear_acl(lli);
        lli->lli_inode_magic = LLI_INODE_DEAD;

        if (S_ISDIR(inode->i_mode))
                ll_dir_clear_lsm_md(inode);
        else if (S_ISREG(inode->i_mode) && !is_bad_inode(inode))
                LASSERT(list_empty(&lli->lli_agl_list));

        /*
         * XXX This has to be done before lsm is freed below, because
         * cl_object still uses inode lsm.
         */
        cl_inode_fini(inode);

        llcrypt_put_encryption_info(inode);

        EXIT;
}

static int ll_md_setattr(struct dentry *dentry, struct md_op_data *op_data)
{
        struct lustre_md md;
        struct inode *inode = dentry->d_inode;
        struct ll_sb_info *sbi = ll_i2sbi(inode);
        struct ptlrpc_request *request = NULL;
        int rc, ia_valid;
        ENTRY;

        op_data = ll_prep_md_op_data(op_data, inode, NULL, NULL, 0, 0,
                                     LUSTRE_OPC_ANY, NULL);
        if (IS_ERR(op_data))
                RETURN(PTR_ERR(op_data));

        rc = md_setattr(sbi->ll_md_exp, op_data, NULL, 0, &request);
        if (rc) {
                ptlrpc_req_finished(request);
                if (rc == -ENOENT) {
                        clear_nlink(inode);
                        /* Unlinked special device node? Or just a race?
                         * Pretend we done everything. */
                        if (!S_ISREG(inode->i_mode) &&
                            !S_ISDIR(inode->i_mode)) {
                                ia_valid = op_data->op_attr.ia_valid;
                                op_data->op_attr.ia_valid &= ~TIMES_SET_FLAGS;
                                rc = simple_setattr(dentry, &op_data->op_attr);
                                op_data->op_attr.ia_valid = ia_valid;
                        }
                } else if (rc != -EPERM && rc != -EACCES && rc != -ETXTBSY) {
                        CERROR("md_setattr fails: rc = %d\n", rc);
                }
                RETURN(rc);
        }

        rc = md_get_lustre_md(sbi->ll_md_exp, request, sbi->ll_dt_exp,
                              sbi->ll_md_exp, &md);
        if (rc) {
                ptlrpc_req_finished(request);
                RETURN(rc);
        }

        ia_valid = op_data->op_attr.ia_valid;
        /* inode size will be in ll_setattr_ost, can't do it now since dirty
         * cache is not cleared yet. */
        op_data->op_attr.ia_valid &= ~(TIMES_SET_FLAGS | ATTR_SIZE);
        if (S_ISREG(inode->i_mode))
                inode_lock(inode);
        rc = simple_setattr(dentry, &op_data->op_attr);
        if (S_ISREG(inode->i_mode))
                inode_unlock(inode);
        op_data->op_attr.ia_valid = ia_valid;

        rc = ll_update_inode(inode, &md);
        ptlrpc_req_finished(request);

        RETURN(rc);
}

/**
 * Zero portion of page that is part of @inode.
 * This implies, if necessary:
 * - taking cl_lock on range corresponding to concerned page
 * - grabbing vm page
 * - associating cl_page
 * - proceeding to clio read
 * - zeroing range in page
 * - proceeding to cl_page flush
 * - releasing cl_lock
 *
 * \param[in] inode     inode
 * \param[in] index     page index
 * \param[in] offset    offset in page to start zero from
 * \param[in] len       len to zero
 *
 * \retval 0            on success
 * \retval negative     errno on failure
 */
int ll_io_zero_page(struct inode *inode, pgoff_t index, pgoff_t offset,
                    unsigned len)
{
        struct ll_inode_info *lli = ll_i2info(inode);
        struct cl_object *clob = lli->lli_clob;
        __u16 refcheck;
        struct lu_env *env = NULL;
        struct cl_io *io = NULL;
        struct cl_page *clpage = NULL;
        struct page *vmpage = NULL;
        unsigned from = index << PAGE_SHIFT;
        struct cl_lock *lock = NULL;
        struct cl_lock_descr *descr = NULL;
        struct cl_2queue *queue = NULL;
        struct cl_sync_io *anchor = NULL;
        bool holdinglock = false;
        bool lockedbymyself = true;
        int rc;

        ENTRY;

        env = cl_env_get(&refcheck);
        if (IS_ERR(env))
                RETURN(PTR_ERR(env));

        io = vvp_env_thread_io(env);
        io->ci_obj = clob;
        rc = cl_io_rw_init(env, io, CIT_WRITE, from, PAGE_SIZE);
        if (rc)
                GOTO(putenv, rc);

        lock = vvp_env_lock(env);
        descr = &lock->cll_descr;
        descr->cld_obj   = io->ci_obj;
        descr->cld_start = cl_index(io->ci_obj, from);
        descr->cld_end   = cl_index(io->ci_obj, from + PAGE_SIZE - 1);
        descr->cld_mode  = CLM_WRITE;
        descr->cld_enq_flags = CEF_MUST | CEF_NONBLOCK;

        /* request lock for page */
        rc = cl_lock_request(env, io, lock);
        /* -ECANCELED indicates a matching lock with a different extent
         * was already present, and -EEXIST indicates a matching lock
         * on exactly the same extent was already present.
         * In both cases it means we are covered.
         */
        if (rc == -ECANCELED || rc == -EEXIST)
                rc = 0;
        else if (rc < 0)
                GOTO(iofini, rc);
        else
                holdinglock = true;

        /* grab page */
        vmpage = grab_cache_page_nowait(inode->i_mapping, index);
        if (vmpage == NULL)
                GOTO(rellock, rc = -EOPNOTSUPP);

        if (!PageDirty(vmpage)) {
                /* associate cl_page */
                clpage = cl_page_find(env, clob, vmpage->index,
                                      vmpage, CPT_CACHEABLE);
                if (IS_ERR(clpage))
                        GOTO(pagefini, rc = PTR_ERR(clpage));

                cl_page_assume(env, io, clpage);
        }

        if (!PageUptodate(vmpage) && !PageDirty(vmpage) &&
            !PageWriteback(vmpage)) {
                /* read page */
                /* set PagePrivate2 to detect special case of empty page
                 * in osc_brw_fini_request()
                 */
                SetPagePrivate2(vmpage);
                rc = ll_io_read_page(env, io, clpage, NULL);
                if (!PagePrivate2(vmpage))
                        /* PagePrivate2 was cleared in osc_brw_fini_request()
                         * meaning we read an empty page. In this case, in order
                         * to avoid allocating unnecessary block in truncated
                         * file, we must not zero and write as below. Subsequent
                         * server-side truncate will handle things correctly.
                         */
                        GOTO(clpfini, rc = 0);
                ClearPagePrivate2(vmpage);
                if (rc)
                        GOTO(clpfini, rc);
                lockedbymyself = trylock_page(vmpage);
                cl_page_assume(env, io, clpage);
        }

        /* zero range in page */
        zero_user(vmpage, offset, len);

        if (holdinglock && clpage) {
                /* explicitly write newly modified page */
                queue = &io->ci_queue;
                cl_2queue_init(queue);
                anchor = &vvp_env_info(env)->vti_anchor;
                cl_sync_io_init(anchor, 1);
                clpage->cp_sync_io = anchor;
                cl_2queue_add(queue, clpage);
                rc = cl_io_submit_rw(env, io, CRT_WRITE, queue);
                if (rc)
                        GOTO(queuefini1, rc);
                rc = cl_sync_io_wait(env, anchor, 0);
                if (rc)
                        GOTO(queuefini2, rc);
                cl_page_assume(env, io, clpage);

queuefini2:
                cl_2queue_discard(env, io, queue);
queuefini1:
                cl_2queue_disown(env, io, queue);
                cl_2queue_fini(env, queue);
        }

clpfini:
        if (clpage)
                cl_page_put(env, clpage);
pagefini:
        if (lockedbymyself) {
                unlock_page(vmpage);
                put_page(vmpage);
        }
rellock:
        if (holdinglock)
                cl_lock_release(env, lock);
iofini:
        cl_io_fini(env, io);
putenv:
        if (env)
                cl_env_put(env, &refcheck);

        RETURN(rc);
}

/* If this inode has objects allocated to it (lsm != NULL), then the OST
 * object(s) determine the file size and mtime.  Otherwise, the MDS will
 * keep these values until such a time that objects are allocated for it.
 * We do the MDS operations first, as it is checking permissions for us.
 * We don't to the MDS RPC if there is nothing that we want to store there,
 * otherwise there is no harm in updating mtime/atime on the MDS if we are
 * going to do an RPC anyways.
 *
 * If we are doing a truncate, we will send the mtime and ctime updates
 * to the OST with the punch RPC, otherwise we do an explicit setattr RPC.
 * I don't believe it is possible to get e.g. ATTR_MTIME_SET and ATTR_SIZE
 * at the same time.
 *
 * In case of HSMimport, we only set attr on MDS.
 */
int ll_setattr_raw(struct dentry *dentry, struct iattr *attr,
                   enum op_xvalid xvalid, bool hsm_import)
{
        struct inode *inode = dentry->d_inode;
        struct ll_inode_info *lli = ll_i2info(inode);
        struct md_op_data *op_data = NULL;
        ktime_t kstart = ktime_get();
        int rc = 0;

        ENTRY;

        CDEBUG(D_VFSTRACE, "%s: setattr inode "DFID"(%p) from %llu to %llu, "
               "valid %x, hsm_import %d\n",
               ll_i2sbi(inode)->ll_fsname, PFID(&lli->lli_fid),
               inode, i_size_read(inode), attr->ia_size, attr->ia_valid,
               hsm_import);

        if (attr->ia_valid & ATTR_SIZE) {
                /* Check new size against VFS/VM file size limit and rlimit */
                rc = inode_newsize_ok(inode, attr->ia_size);
                if (rc)
                        RETURN(rc);

                /* The maximum Lustre file size is variable, based on the
                 * OST maximum object size and number of stripes.  This
                 * needs another check in addition to the VFS check above. */
                if (attr->ia_size > ll_file_maxbytes(inode)) {
                        CDEBUG(D_INODE,"file "DFID" too large %llu > %llu\n",
                               PFID(&lli->lli_fid), attr->ia_size,
                               ll_file_maxbytes(inode));
                        RETURN(-EFBIG);
                }

                attr->ia_valid |= ATTR_MTIME | ATTR_CTIME;
        }

        /* POSIX: check before ATTR_*TIME_SET set (from inode_change_ok) */
        if (attr->ia_valid & TIMES_SET_FLAGS) {
                if ((!uid_eq(current_fsuid(), inode->i_uid)) &&
                    !capable(CAP_FOWNER))
                        RETURN(-EPERM);
        }

        /* We mark all of the fields "set" so MDS/OST does not re-set them */
        if (!(xvalid & OP_XVALID_CTIME_SET) &&
             (attr->ia_valid & ATTR_CTIME)) {
                attr->ia_ctime = current_time(inode);
                xvalid |= OP_XVALID_CTIME_SET;
        }
        if (!(attr->ia_valid & ATTR_ATIME_SET) &&
            (attr->ia_valid & ATTR_ATIME)) {
                attr->ia_atime = current_time(inode);
                attr->ia_valid |= ATTR_ATIME_SET;
        }
        if (!(attr->ia_valid & ATTR_MTIME_SET) &&
            (attr->ia_valid & ATTR_MTIME)) {
                attr->ia_mtime = current_time(inode);
                attr->ia_valid |= ATTR_MTIME_SET;
        }

        if (attr->ia_valid & (ATTR_MTIME | ATTR_CTIME))
                CDEBUG(D_INODE, "setting mtime %lld, ctime %lld, now = %lld\n",
                       (s64)attr->ia_mtime.tv_sec, (s64)attr->ia_ctime.tv_sec,
                       ktime_get_real_seconds());

        if (S_ISREG(inode->i_mode))
                inode_unlock(inode);

        /* We always do an MDS RPC, even if we're only changing the size;
         * only the MDS knows whether truncate() should fail with -ETXTBUSY */

        OBD_ALLOC_PTR(op_data);
        if (op_data == NULL)
                GOTO(out, rc = -ENOMEM);

        if (!hsm_import && attr->ia_valid & ATTR_SIZE) {
                /* If we are changing file size, file content is
                 * modified, flag it.
                 */
                xvalid |= OP_XVALID_OWNEROVERRIDE;
                op_data->op_bias |= MDS_DATA_MODIFIED;
                clear_bit(LLIF_DATA_MODIFIED, &lli->lli_flags);
        }

        if (attr->ia_valid & ATTR_FILE) {
                struct ll_file_data *fd = attr->ia_file->private_data;

                if (fd->fd_lease_och)
                        op_data->op_bias |= MDS_TRUNC_KEEP_LEASE;
        }

        op_data->op_attr = *attr;
        op_data->op_xvalid = xvalid;

        rc = ll_md_setattr(dentry, op_data);
        if (rc)
                GOTO(out, rc);

        if (!S_ISREG(inode->i_mode) || hsm_import)
                GOTO(out, rc = 0);

        if (attr->ia_valid & (ATTR_SIZE | ATTR_ATIME | ATTR_ATIME_SET |
                              ATTR_MTIME | ATTR_MTIME_SET | ATTR_CTIME) ||
            xvalid & OP_XVALID_CTIME_SET) {
                bool cached = false;

                rc = pcc_inode_setattr(inode, attr, &cached);
                if (cached) {
                        if (rc) {
                                CERROR("%s: PCC inode "DFID" setattr failed: "
                                       "rc = %d\n",
                                       ll_i2sbi(inode)->ll_fsname,
                                       PFID(&lli->lli_fid), rc);
                                GOTO(out, rc);
                        }
                } else {
                        unsigned int flags = 0;

                        /* For truncate and utimes sending attributes to OSTs,
                         * setting mtime/atime to the past will be performed
                         * under PW [0:EOF] extent lock (new_size:EOF for
                         * truncate). It may seem excessive to send mtime/atime
                         * updates to OSTs when not setting times to past, but
                         * it is necessary due to possible time
                         * de-synchronization between MDT inode and OST objects
                         */
                        if (S_ISREG(inode->i_mode) && IS_ENCRYPTED(inode) &&
                            attr->ia_valid & ATTR_SIZE) {
                                xvalid |= OP_XVALID_FLAGS;
                                flags = LUSTRE_ENCRYPT_FL;
                                /* Call to ll_io_zero_page is not necessary if
                                 * truncating on PAGE_SIZE boundary, because
                                 * whole pages will be wiped.
                                 * In case of Direct IO, all we need is to set
                                 * new size.
                                 */
                                if (attr->ia_size & ~PAGE_MASK &&
                                    !(attr->ia_valid & ATTR_FILE &&
                                      attr->ia_file->f_flags & O_DIRECT)) {
                                        pgoff_t offset =
                                                attr->ia_size & (PAGE_SIZE - 1);

                                        rc = ll_io_zero_page(inode,
                                                    attr->ia_size >> PAGE_SHIFT,
                                                    offset, PAGE_SIZE - offset);
                                        if (rc)
                                                GOTO(out, rc);
                                }
                        }
                        rc = cl_setattr_ost(lli->lli_clob, attr, xvalid, flags);
                }
        }

        /* If the file was restored, it needs to set dirty flag.
         *
         * We've already sent MDS_DATA_MODIFIED flag in
         * ll_md_setattr() for truncate. However, the MDT refuses to
         * set the HS_DIRTY flag on released files, so we have to set
         * it again if the file has been restored. Please check how
         * LLIF_DATA_MODIFIED is set in vvp_io_setattr_fini().
         *
         * Please notice that if the file is not released, the previous
         * MDS_DATA_MODIFIED has taken effect and usually
         * LLIF_DATA_MODIFIED is not set(see vvp_io_setattr_fini()).
         * This way we can save an RPC for common open + trunc
         * operation. */
        if (test_and_clear_bit(LLIF_DATA_MODIFIED, &lli->lli_flags)) {
                struct hsm_state_set hss = {
                        .hss_valid = HSS_SETMASK,
                        .hss_setmask = HS_DIRTY,
                };
                int rc2;

                rc2 = ll_hsm_state_set(inode, &hss);
                /* truncate and write can happen at the same time, so that
                 * the file can be set modified even though the file is not
                 * restored from released state, and ll_hsm_state_set() is
                 * not applicable for the file, and rc2 < 0 is normal in this
                 * case. */
                if (rc2 < 0)
                        CDEBUG(D_INFO, DFID "HSM set dirty failed: rc2 = %d\n",
                               PFID(ll_inode2fid(inode)), rc2);
        }

        EXIT;
out:
        if (op_data != NULL)
                ll_finish_md_op_data(op_data);

        if (S_ISREG(inode->i_mode)) {
                inode_lock(inode);
                if ((attr->ia_valid & ATTR_SIZE) && !hsm_import)
                        inode_dio_wait(inode);
                /* Once we've got the i_mutex, it's safe to set the S_NOSEC
                 * flag.  ll_update_inode (called from ll_md_setattr), clears
                 * inode flags, so there is a gap where S_NOSEC is not set.
                 * This can cause a writer to take the i_mutex unnecessarily,
                 * but this is safe to do and should be rare. */
                inode_has_no_xattr(inode);
        }

        if (!rc)
                ll_stats_ops_tally(ll_i2sbi(inode), attr->ia_valid & ATTR_SIZE ?
                                        LPROC_LL_TRUNC : LPROC_LL_SETATTR,
                                   ktime_us_delta(ktime_get(), kstart));

        return rc;
}

int ll_setattr(struct dentry *de, struct iattr *attr)
{
        int mode = de->d_inode->i_mode;
        enum op_xvalid xvalid = 0;
        int rc;

        rc = llcrypt_prepare_setattr(de, attr);
        if (rc)
                return rc;

        if ((attr->ia_valid & (ATTR_CTIME|ATTR_SIZE|ATTR_MODE)) ==
                              (ATTR_CTIME|ATTR_SIZE|ATTR_MODE))
                xvalid |= OP_XVALID_OWNEROVERRIDE;

        if (((attr->ia_valid & (ATTR_MODE|ATTR_FORCE|ATTR_SIZE)) ==
                               (ATTR_SIZE|ATTR_MODE)) &&
            (((mode & S_ISUID) && !(attr->ia_mode & S_ISUID)) ||
             (((mode & (S_ISGID|S_IXGRP)) == (S_ISGID|S_IXGRP)) &&
              !(attr->ia_mode & S_ISGID))))
                attr->ia_valid |= ATTR_FORCE;

        if ((attr->ia_valid & ATTR_MODE) &&
            (mode & S_ISUID) &&
            !(attr->ia_mode & S_ISUID) &&
            !(attr->ia_valid & ATTR_KILL_SUID))
                attr->ia_valid |= ATTR_KILL_SUID;

        if ((attr->ia_valid & ATTR_MODE) &&
            ((mode & (S_ISGID|S_IXGRP)) == (S_ISGID|S_IXGRP)) &&
            !(attr->ia_mode & S_ISGID) &&
            !(attr->ia_valid & ATTR_KILL_SGID))
                attr->ia_valid |= ATTR_KILL_SGID;

        return ll_setattr_raw(de, attr, xvalid, false);
}

int ll_statfs_internal(struct ll_sb_info *sbi, struct obd_statfs *osfs,
                       u32 flags)
{
        struct obd_statfs obd_osfs = { 0 };
        time64_t max_age;
        int rc;

        ENTRY;
        max_age = ktime_get_seconds() - sbi->ll_statfs_max_age;

        if (sbi->ll_flags & LL_SBI_LAZYSTATFS)
                flags |= OBD_STATFS_NODELAY;

        rc = obd_statfs(NULL, sbi->ll_md_exp, osfs, max_age, flags);
        if (rc)
                RETURN(rc);

        osfs->os_type = LL_SUPER_MAGIC;

        CDEBUG(D_SUPER, "MDC blocks %llu/%llu objects %llu/%llu\n",
              osfs->os_bavail, osfs->os_blocks, osfs->os_ffree, osfs->os_files);

        if (osfs->os_state & OS_STATFS_SUM)
                GOTO(out, rc);

        rc = obd_statfs(NULL, sbi->ll_dt_exp, &obd_osfs, max_age, flags);
        if (rc) /* Possibly a filesystem with no OSTs.  Report MDT totals. */
                GOTO(out, rc = 0);

        CDEBUG(D_SUPER, "OSC blocks %llu/%llu objects %llu/%llu\n",
               obd_osfs.os_bavail, obd_osfs.os_blocks, obd_osfs.os_ffree,
               obd_osfs.os_files);

        osfs->os_bsize = obd_osfs.os_bsize;
        osfs->os_blocks = obd_osfs.os_blocks;
        osfs->os_bfree = obd_osfs.os_bfree;
        osfs->os_bavail = obd_osfs.os_bavail;

        /* If we have _some_ OSTs, but don't have as many free objects on the
         * OSTs as inodes on the MDTs, reduce the reported number of inodes
         * to compensate, so that the "inodes in use" number is correct.
         * This should be kept in sync with lod_statfs() behaviour.
         */
        if (obd_osfs.os_files && obd_osfs.os_ffree < osfs->os_ffree) {
                osfs->os_files = (osfs->os_files - osfs->os_ffree) +
                                 obd_osfs.os_ffree;
                osfs->os_ffree = obd_osfs.os_ffree;
        }

out:
        RETURN(rc);
}

static int ll_statfs_project(struct inode *inode, struct kstatfs *sfs)
{
        struct if_quotactl qctl = {
                .qc_cmd = LUSTRE_Q_GETQUOTA,
                .qc_type = PRJQUOTA,
                .qc_valid = QC_GENERAL,
        };
        u64 limit, curblock;
        int ret;

        qctl.qc_id = ll_i2info(inode)->lli_projid;
        ret = quotactl_ioctl(ll_i2sbi(inode), &qctl);
        if (ret) {
                /* ignore errors if project ID does not have
                 * a quota limit or feature unsupported.
                 */
                if (ret == -ESRCH || ret == -EOPNOTSUPP)
                        ret = 0;
                return ret;
        }

        limit = ((qctl.qc_dqblk.dqb_bsoftlimit ?
                 qctl.qc_dqblk.dqb_bsoftlimit :
                 qctl.qc_dqblk.dqb_bhardlimit) * 1024) / sfs->f_bsize;
        if (limit && sfs->f_blocks > limit) {
                curblock = (qctl.qc_dqblk.dqb_curspace +
                                sfs->f_bsize - 1) / sfs->f_bsize;
                sfs->f_blocks = limit;
                sfs->f_bfree = sfs->f_bavail =
                        (sfs->f_blocks > curblock) ?
                        (sfs->f_blocks - curblock) : 0;
        }

        limit = qctl.qc_dqblk.dqb_isoftlimit ?
                qctl.qc_dqblk.dqb_isoftlimit :
                qctl.qc_dqblk.dqb_ihardlimit;
        if (limit && sfs->f_files > limit) {
                sfs->f_files = limit;
                sfs->f_ffree = (sfs->f_files >
                        qctl.qc_dqblk.dqb_curinodes) ?
                        (sfs->f_files - qctl.qc_dqblk.dqb_curinodes) : 0;
        }

        return 0;
}

int ll_statfs(struct dentry *de, struct kstatfs *sfs)
{
        struct super_block *sb = de->d_sb;
        struct obd_statfs osfs;
        __u64 fsid = huge_encode_dev(sb->s_dev);
        ktime_t kstart = ktime_get();
        int rc;

        CDEBUG(D_VFSTRACE, "VFS Op:sb=%s (%p)\n", sb->s_id, sb);

        /* Some amount of caching on the client is allowed */
        rc = ll_statfs_internal(ll_s2sbi(sb), &osfs, OBD_STATFS_SUM);
        if (rc)
                return rc;

        statfs_unpack(sfs, &osfs);

        /* We need to downshift for all 32-bit kernels, because we can't
         * tell if the kernel is being called via sys_statfs64() or not.
         * Stop before overflowing f_bsize - in which case it is better
         * to just risk EOVERFLOW if caller is using old sys_statfs(). */
        if (sizeof(long) < 8) {
                while (osfs.os_blocks > ~0UL && sfs->f_bsize < 0x40000000) {
                        sfs->f_bsize <<= 1;

                        osfs.os_blocks >>= 1;
                        osfs.os_bfree >>= 1;
                        osfs.os_bavail >>= 1;
                }
        }

        sfs->f_blocks = osfs.os_blocks;
        sfs->f_bfree = osfs.os_bfree;
        sfs->f_bavail = osfs.os_bavail;
        sfs->f_fsid.val[0] = (__u32)fsid;
        sfs->f_fsid.val[1] = (__u32)(fsid >> 32);
        if (ll_i2info(de->d_inode)->lli_projid)
                return ll_statfs_project(de->d_inode, sfs);

        ll_stats_ops_tally(ll_s2sbi(sb), LPROC_LL_STATFS,
                           ktime_us_delta(ktime_get(), kstart));

        return 0;
}

void ll_inode_size_lock(struct inode *inode)
{
        struct ll_inode_info *lli;

        LASSERT(!S_ISDIR(inode->i_mode));

        lli = ll_i2info(inode);
        mutex_lock(&lli->lli_size_mutex);
}

void ll_inode_size_unlock(struct inode *inode)
{
        struct ll_inode_info *lli;

        lli = ll_i2info(inode);
        mutex_unlock(&lli->lli_size_mutex);
}

void ll_update_inode_flags(struct inode *inode, unsigned int ext_flags)
{
        /* do not clear encryption flag */
        ext_flags |= ll_inode_to_ext_flags(inode->i_flags) & LUSTRE_ENCRYPT_FL;
        inode->i_flags = ll_ext_to_inode_flags(ext_flags);
        if (ext_flags & LUSTRE_PROJINHERIT_FL)
                set_bit(LLIF_PROJECT_INHERIT, &ll_i2info(inode)->lli_flags);
        else
                clear_bit(LLIF_PROJECT_INHERIT, &ll_i2info(inode)->lli_flags);
}

int ll_update_inode(struct inode *inode, struct lustre_md *md)
{
        struct ll_inode_info *lli = ll_i2info(inode);
        struct mdt_body *body = md->body;
        struct ll_sb_info *sbi = ll_i2sbi(inode);
        int rc = 0;

        if (body->mbo_valid & OBD_MD_FLEASIZE) {
                rc = cl_file_inode_init(inode, md);
                if (rc)
                        return rc;
        }

        if (S_ISDIR(inode->i_mode)) {
                rc = ll_update_lsm_md(inode, md);
                if (rc != 0)
                        return rc;
        }

        if (body->mbo_valid & OBD_MD_FLACL)
                lli_replace_acl(lli, md);

        inode->i_ino = cl_fid_build_ino(&body->mbo_fid1,
                                        sbi->ll_flags & LL_SBI_32BIT_API);
        inode->i_generation = cl_fid_build_gen(&body->mbo_fid1);

        if (body->mbo_valid & OBD_MD_FLATIME) {
                if (body->mbo_atime > inode->i_atime.tv_sec)
                        inode->i_atime.tv_sec = body->mbo_atime;
                lli->lli_atime = body->mbo_atime;
        }

        if (body->mbo_valid & OBD_MD_FLMTIME) {
                if (body->mbo_mtime > inode->i_mtime.tv_sec) {
                        CDEBUG(D_INODE,
                               "setting ino %lu mtime from %lld to %llu\n",
                               inode->i_ino, (s64)inode->i_mtime.tv_sec,
                               body->mbo_mtime);
                        inode->i_mtime.tv_sec = body->mbo_mtime;
                }
                lli->lli_mtime = body->mbo_mtime;
        }

        if (body->mbo_valid & OBD_MD_FLCTIME) {
                if (body->mbo_ctime > inode->i_ctime.tv_sec)
                        inode->i_ctime.tv_sec = body->mbo_ctime;
                lli->lli_ctime = body->mbo_ctime;
        }

        if (body->mbo_valid & OBD_MD_FLBTIME)
                lli->lli_btime = body->mbo_btime;

        /* Clear i_flags to remove S_NOSEC before permissions are updated */
        if (body->mbo_valid & OBD_MD_FLFLAGS)
                ll_update_inode_flags(inode, body->mbo_flags);
        if (body->mbo_valid & OBD_MD_FLMODE)
                inode->i_mode = (inode->i_mode & S_IFMT) |
                                (body->mbo_mode & ~S_IFMT);

        if (body->mbo_valid & OBD_MD_FLTYPE)
                inode->i_mode = (inode->i_mode & ~S_IFMT) |
                                (body->mbo_mode & S_IFMT);

        LASSERT(inode->i_mode != 0);
        if (body->mbo_valid & OBD_MD_FLUID)
                inode->i_uid = make_kuid(&init_user_ns, body->mbo_uid);
        if (body->mbo_valid & OBD_MD_FLGID)
                inode->i_gid = make_kgid(&init_user_ns, body->mbo_gid);
        if (body->mbo_valid & OBD_MD_FLPROJID)
                lli->lli_projid = body->mbo_projid;
        if (body->mbo_valid & OBD_MD_FLNLINK)
                set_nlink(inode, body->mbo_nlink);
        if (body->mbo_valid & OBD_MD_FLRDEV)
                inode->i_rdev = old_decode_dev(body->mbo_rdev);

        if (body->mbo_valid & OBD_MD_FLID) {
                /* FID shouldn't be changed! */
                if (fid_is_sane(&lli->lli_fid)) {
                        LASSERTF(lu_fid_eq(&lli->lli_fid, &body->mbo_fid1),
                                 "Trying to change FID "DFID
                                 " to the "DFID", inode "DFID"(%p)\n",
                                 PFID(&lli->lli_fid), PFID(&body->mbo_fid1),
                                 PFID(ll_inode2fid(inode)), inode);
                } else {
                        lli->lli_fid = body->mbo_fid1;
                }
        }

        LASSERT(fid_seq(&lli->lli_fid) != 0);

        lli->lli_attr_valid = body->mbo_valid;
        if (body->mbo_valid & OBD_MD_FLSIZE) {
                i_size_write(inode, body->mbo_size);

                CDEBUG(D_VFSTRACE, "inode="DFID", updating i_size %llu\n",
                       PFID(ll_inode2fid(inode)),
                       (unsigned long long)body->mbo_size);

                if (body->mbo_valid & OBD_MD_FLBLOCKS)
                        inode->i_blocks = body->mbo_blocks;
        } else {
                if (body->mbo_valid & OBD_MD_FLLAZYSIZE)
                        lli->lli_lazysize = body->mbo_size;
                if (body->mbo_valid & OBD_MD_FLLAZYBLOCKS)
                        lli->lli_lazyblocks = body->mbo_blocks;
        }

        if (body->mbo_valid & OBD_MD_TSTATE) {
                /* Set LLIF_FILE_RESTORING if restore ongoing and
                 * clear it when done to ensure to start again
                 * glimpsing updated attrs
                 */
                if (body->mbo_t_state & MS_RESTORE)
                        set_bit(LLIF_FILE_RESTORING, &lli->lli_flags);
                else
                        clear_bit(LLIF_FILE_RESTORING, &lli->lli_flags);
        }

        return 0;
}

int ll_read_inode2(struct inode *inode, void *opaque)
{
        struct lustre_md *md = opaque;
        struct ll_inode_info *lli = ll_i2info(inode);
        int     rc;
        ENTRY;

        CDEBUG(D_VFSTRACE, "VFS Op:inode="DFID"(%p)\n",
               PFID(&lli->lli_fid), inode);

        /* Core attributes from the MDS first.  This is a new inode, and
         * the VFS doesn't zero times in the core inode so we have to do
         * it ourselves.  They will be overwritten by either MDS or OST
         * attributes - we just need to make sure they aren't newer.
         */
        inode->i_mtime.tv_sec = 0;
        inode->i_atime.tv_sec = 0;
        inode->i_ctime.tv_sec = 0;
        inode->i_rdev = 0;
        rc = ll_update_inode(inode, md);
        if (rc != 0)
                RETURN(rc);

        /* OIDEBUG(inode); */

#ifdef HAVE_BACKING_DEV_INFO
        /* initializing backing dev info. */
        inode->i_mapping->backing_dev_info = &s2lsi(inode->i_sb)->lsi_bdi;
#endif
        if (S_ISREG(inode->i_mode)) {
                struct ll_sb_info *sbi = ll_i2sbi(inode);
                inode->i_op = &ll_file_inode_operations;
                inode->i_fop = sbi->ll_fop;
                inode->i_mapping->a_ops = (struct address_space_operations *)&ll_aops;
                EXIT;
        } else if (S_ISDIR(inode->i_mode)) {
                inode->i_op = &ll_dir_inode_operations;
                inode->i_fop = &ll_dir_operations;
                EXIT;
        } else if (S_ISLNK(inode->i_mode)) {
                inode->i_op = &ll_fast_symlink_inode_operations;
                EXIT;
        } else {
                inode->i_op = &ll_special_inode_operations;

                init_special_inode(inode, inode->i_mode,
                                   inode->i_rdev);

                EXIT;
        }

        return 0;
}

void ll_delete_inode(struct inode *inode)
{
        struct ll_inode_info *lli = ll_i2info(inode);
        struct address_space *mapping = &inode->i_data;
        unsigned long nrpages;
        unsigned long flags;

        ENTRY;

        if (S_ISREG(inode->i_mode) && lli->lli_clob != NULL) {
                /* It is last chance to write out dirty pages,
                 * otherwise we may lose data while umount.
                 *
                 * If i_nlink is 0 then just discard data. This is safe because
                 * local inode gets i_nlink 0 from server only for the last
                 * unlink, so that file is not opened somewhere else
                 */
                cl_sync_file_range(inode, 0, OBD_OBJECT_EOF, inode->i_nlink ?
                                   CL_FSYNC_LOCAL : CL_FSYNC_DISCARD, 1);
        }
        truncate_inode_pages_final(mapping);

        /* Workaround for LU-118: Note nrpages may not be totally updated when
         * truncate_inode_pages() returns, as there can be a page in the process
         * of deletion (inside __delete_from_page_cache()) in the specified
         * range. Thus mapping->nrpages can be non-zero when this function
         * returns even after truncation of the whole mapping.  Only do this if
         * npages isn't already zero.
         */
        nrpages = mapping->nrpages;
        if (nrpages) {
                ll_xa_lock_irqsave(&mapping->i_pages, flags);
                nrpages = mapping->nrpages;
                ll_xa_unlock_irqrestore(&mapping->i_pages, flags);
        } /* Workaround end */

        LASSERTF(nrpages == 0, "%s: inode="DFID"(%p) nrpages=%lu, "
                 "see https://jira.whamcloud.com/browse/LU-118\n",
                 ll_i2sbi(inode)->ll_fsname,
                 PFID(ll_inode2fid(inode)), inode, nrpages);

        ll_clear_inode(inode);
        clear_inode(inode);

        EXIT;
}

int ll_iocontrol(struct inode *inode, struct file *file,
                 unsigned int cmd, unsigned long arg)
{
        struct ll_sb_info *sbi = ll_i2sbi(inode);
        struct ptlrpc_request *req = NULL;
        int rc, flags = 0;
        ENTRY;

        switch (cmd) {
        case FS_IOC_GETFLAGS: {
                struct mdt_body *body;
                struct md_op_data *op_data;

                op_data = ll_prep_md_op_data(NULL, inode, NULL, NULL,
                                             0, 0, LUSTRE_OPC_ANY,
                                             NULL);
                if (IS_ERR(op_data))
                        RETURN(PTR_ERR(op_data));

                op_data->op_valid = OBD_MD_FLFLAGS;
                rc = md_getattr(sbi->ll_md_exp, op_data, &req);
                ll_finish_md_op_data(op_data);
                if (rc) {
                        CERROR("%s: failure inode "DFID": rc = %d\n",
                               sbi->ll_md_exp->exp_obd->obd_name,
                               PFID(ll_inode2fid(inode)), rc);
                        RETURN(-abs(rc));
                }

                body = req_capsule_server_get(&req->rq_pill, &RMF_MDT_BODY);

                flags = body->mbo_flags;

                ptlrpc_req_finished(req);

                RETURN(put_user(flags, (int __user *)arg));
        }
        case FS_IOC_SETFLAGS: {
                struct iattr *attr;
                struct md_op_data *op_data;
                struct cl_object *obj;
                struct fsxattr fa = { 0 };

                if (get_user(flags, (int __user *)arg))
                        RETURN(-EFAULT);

                fa.fsx_projid = ll_i2info(inode)->lli_projid;
                if (flags & LUSTRE_PROJINHERIT_FL)
                        fa.fsx_xflags = FS_XFLAG_PROJINHERIT;

                rc = ll_ioctl_check_project(inode, &fa);
                if (rc)
                        RETURN(rc);

                op_data = ll_prep_md_op_data(NULL, inode, NULL, NULL, 0, 0,
                                             LUSTRE_OPC_ANY, NULL);
                if (IS_ERR(op_data))
                        RETURN(PTR_ERR(op_data));

                op_data->op_attr_flags = flags;
                op_data->op_xvalid |= OP_XVALID_FLAGS;
                rc = md_setattr(sbi->ll_md_exp, op_data, NULL, 0, &req);
                ll_finish_md_op_data(op_data);
                ptlrpc_req_finished(req);
                if (rc)
                        RETURN(rc);

                ll_update_inode_flags(inode, flags);

                obj = ll_i2info(inode)->lli_clob;
                if (obj == NULL)
                        RETURN(0);

                OBD_ALLOC_PTR(attr);
                if (attr == NULL)
                        RETURN(-ENOMEM);

                rc = cl_setattr_ost(obj, attr, OP_XVALID_FLAGS, flags);

                OBD_FREE_PTR(attr);
                RETURN(rc);
        }
        default:
                RETURN(-ENOSYS);
        }

        RETURN(0);
}

int ll_flush_ctx(struct inode *inode)
{
        struct ll_sb_info  *sbi = ll_i2sbi(inode);

        CDEBUG(D_SEC, "flush context for user %d\n",
               from_kuid(&init_user_ns, current_uid()));

        obd_set_info_async(NULL, sbi->ll_md_exp,
                           sizeof(KEY_FLUSH_CTX), KEY_FLUSH_CTX,
                           0, NULL, NULL);
        obd_set_info_async(NULL, sbi->ll_dt_exp,
                           sizeof(KEY_FLUSH_CTX), KEY_FLUSH_CTX,
                           0, NULL, NULL);
        return 0;
}

/* umount -f client means force down, don't save state */
void ll_umount_begin(struct super_block *sb)
{
        struct ll_sb_info *sbi = ll_s2sbi(sb);
        struct obd_device *obd;
        struct obd_ioctl_data *ioc_data;
        int cnt;
        ENTRY;

        CDEBUG(D_VFSTRACE, "VFS Op: superblock %p count %d active %d\n", sb,
               sb->s_count, atomic_read(&sb->s_active));

        obd = class_exp2obd(sbi->ll_md_exp);
        if (obd == NULL) {
                CERROR("Invalid MDC connection handle %#llx\n",
                       sbi->ll_md_exp->exp_handle.h_cookie);
                EXIT;
                return;
        }
        obd->obd_force = 1;

        obd = class_exp2obd(sbi->ll_dt_exp);
        if (obd == NULL) {
                CERROR("Invalid LOV connection handle %#llx\n",
                       sbi->ll_dt_exp->exp_handle.h_cookie);
                EXIT;
                return;
        }
        obd->obd_force = 1;

        OBD_ALLOC_PTR(ioc_data);
        if (ioc_data) {
                obd_iocontrol(IOC_OSC_SET_ACTIVE, sbi->ll_md_exp,
                              sizeof *ioc_data, ioc_data, NULL);

                obd_iocontrol(IOC_OSC_SET_ACTIVE, sbi->ll_dt_exp,
                              sizeof *ioc_data, ioc_data, NULL);

                OBD_FREE_PTR(ioc_data);
        }

        /* Really, we'd like to wait until there are no requests outstanding,
         * and then continue.  For now, we just periodically checking for vfs
         * to decrement mnt_cnt and hope to finish it within 10sec.
         */
        cnt = 10;
        while (cnt > 0 &&
               !may_umount(sbi->ll_mnt.mnt)) {
                ssleep(1);
                cnt -= 1;
        }

        EXIT;
}

int ll_remount_fs(struct super_block *sb, int *flags, char *data)
{
        struct ll_sb_info *sbi = ll_s2sbi(sb);
        char *profilenm = get_profile_name(sb);
        int err;
        __u32 read_only;

        if ((*flags & MS_RDONLY) != (sb->s_flags & SB_RDONLY)) {
                read_only = *flags & MS_RDONLY;
                err = obd_set_info_async(NULL, sbi->ll_md_exp,
                                         sizeof(KEY_READ_ONLY),
                                         KEY_READ_ONLY, sizeof(read_only),
                                         &read_only, NULL);
                if (err) {
                        LCONSOLE_WARN("Failed to remount %s %s (%d)\n",
                                      profilenm, read_only ?
                                      "read-only" : "read-write", err);
                        return err;
                }

                if (read_only)
                        sb->s_flags |= SB_RDONLY;
                else
                        sb->s_flags &= ~SB_RDONLY;

                if (sbi->ll_flags & LL_SBI_VERBOSE)
                        LCONSOLE_WARN("Remounted %s %s\n", profilenm,
                                      read_only ?  "read-only" : "read-write");
        }
        return 0;
}

/**
 * Cleanup the open handle that is cached on MDT-side.
 *
 * For open case, the client side open handling thread may hit error
 * after the MDT grant the open. Under such case, the client should
 * send close RPC to the MDT as cleanup; otherwise, the open handle
 * on the MDT will be leaked there until the client umount or evicted.
 *
 * In further, if someone unlinked the file, because the open handle
 * holds the reference on such file/object, then it will block the
 * subsequent threads that want to locate such object via FID.
 *
 * \param[in] sb        super block for this file-system
 * \param[in] open_req  pointer to the original open request
 */
void ll_open_cleanup(struct super_block *sb, struct ptlrpc_request *open_req)
{
        struct mdt_body                 *body;
        struct md_op_data               *op_data;
        struct ptlrpc_request           *close_req = NULL;
        struct obd_export               *exp       = ll_s2sbi(sb)->ll_md_exp;
        ENTRY;

        body = req_capsule_server_get(&open_req->rq_pill, &RMF_MDT_BODY);
        OBD_ALLOC_PTR(op_data);
        if (op_data == NULL) {
                CWARN("%s: cannot allocate op_data to release open handle for "
                      DFID"\n", ll_s2sbi(sb)->ll_fsname, PFID(&body->mbo_fid1));

                RETURN_EXIT;
        }

        op_data->op_fid1 = body->mbo_fid1;
        op_data->op_open_handle = body->mbo_open_handle;
        op_data->op_mod_time = ktime_get_real_seconds();
        md_close(exp, op_data, NULL, &close_req);
        ptlrpc_req_finished(close_req);
        ll_finish_md_op_data(op_data);

        EXIT;
}

int ll_prep_inode(struct inode **inode, struct ptlrpc_request *req,
                  struct super_block *sb, struct lookup_intent *it)
{
        struct ll_sb_info *sbi = NULL;
        struct lustre_md md = { NULL };
        bool default_lmv_deleted = false;
        int rc;

        ENTRY;

        LASSERT(*inode || sb);
        sbi = sb ? ll_s2sbi(sb) : ll_i2sbi(*inode);
        rc = md_get_lustre_md(sbi->ll_md_exp, req, sbi->ll_dt_exp,
                              sbi->ll_md_exp, &md);
        if (rc != 0)
                GOTO(out, rc);

        /*
         * clear default_lmv only if intent_getattr reply doesn't contain it.
         * but it needs to be done after iget, check this early because
         * ll_update_lsm_md() may change md.
         */
        if (it && (it->it_op & (IT_LOOKUP | IT_GETATTR)) &&
            S_ISDIR(md.body->mbo_mode) && !md.default_lmv)
                default_lmv_deleted = true;

        if (*inode) {
                rc = ll_update_inode(*inode, &md);
                if (rc != 0)
                        GOTO(out, rc);
        } else {
                LASSERT(sb != NULL);

                /*
                 * At this point server returns to client's same fid as client
                 * generated for creating. So using ->fid1 is okay here.
                 */
                if (!fid_is_sane(&md.body->mbo_fid1)) {
                        CERROR("%s: Fid is insane "DFID"\n",
                                sbi->ll_fsname,
                                PFID(&md.body->mbo_fid1));
                        GOTO(out, rc = -EINVAL);
                }

                *inode = ll_iget(sb, cl_fid_build_ino(&md.body->mbo_fid1,
                                             sbi->ll_flags & LL_SBI_32BIT_API),
                                 &md);
                if (IS_ERR(*inode)) {
                        lmd_clear_acl(&md);
                        rc = IS_ERR(*inode) ? PTR_ERR(*inode) : -ENOMEM;
                        *inode = NULL;
                        CERROR("new_inode -fatal: rc %d\n", rc);
                        GOTO(out, rc);
                }
        }

        /* Handling piggyback layout lock.
         * Layout lock can be piggybacked by getattr and open request.
         * The lsm can be applied to inode only if it comes with a layout lock
         * otherwise correct layout may be overwritten, for example:
         * 1. proc1: mdt returns a lsm but not granting layout
         * 2. layout was changed by another client
         * 3. proc2: refresh layout and layout lock granted
         * 4. proc1: to apply a stale layout */
        if (it != NULL && it->it_lock_mode != 0) {
                struct lustre_handle lockh;
                struct ldlm_lock *lock;

                lockh.cookie = it->it_lock_handle;
                lock = ldlm_handle2lock(&lockh);
                LASSERT(lock != NULL);
                if (ldlm_has_layout(lock)) {
                        struct cl_object_conf conf;

                        memset(&conf, 0, sizeof(conf));
                        conf.coc_opc = OBJECT_CONF_SET;
                        conf.coc_inode = *inode;
                        conf.coc_lock = lock;
                        conf.u.coc_layout = md.layout;
                        (void)ll_layout_conf(*inode, &conf);
                }
                LDLM_LOCK_PUT(lock);
        }

        if (default_lmv_deleted)
                ll_update_default_lsm_md(*inode, &md);

        /* we may want to apply some policy for foreign file/dir */
        if (ll_sbi_has_foreign_symlink(sbi)) {
                rc = ll_manage_foreign(*inode, &md);
                if (rc < 0)
                        GOTO(out, rc);
        }

        GOTO(out, rc = 0);

out:
        /* cleanup will be done if necessary */
        md_free_lustre_md(sbi->ll_md_exp, &md);

        if (rc != 0 && it != NULL && it->it_op & IT_OPEN) {
                ll_intent_drop_lock(it);
                ll_open_cleanup(sb != NULL ? sb : (*inode)->i_sb, req);
        }

        return rc;
}

int ll_obd_statfs(struct inode *inode, void __user *arg)
{
        struct ll_sb_info *sbi = NULL;
        struct obd_export *exp;
        struct obd_ioctl_data *data = NULL;
        __u32 type;
        int len = 0, rc;

        if (inode)
                sbi = ll_i2sbi(inode);
        if (!sbi)
                GOTO(out_statfs, rc = -EINVAL);

        rc = obd_ioctl_getdata(&data, &len, arg);
        if (rc)
                GOTO(out_statfs, rc);

        if (!data->ioc_inlbuf1 || !data->ioc_inlbuf2 ||
            !data->ioc_pbuf1 || !data->ioc_pbuf2)
                GOTO(out_statfs, rc = -EINVAL);

        if (data->ioc_inllen1 != sizeof(__u32) ||
            data->ioc_inllen2 != sizeof(__u32) ||
            data->ioc_plen1 != sizeof(struct obd_statfs) ||
            data->ioc_plen2 != sizeof(struct obd_uuid))
                GOTO(out_statfs, rc = -EINVAL);

        memcpy(&type, data->ioc_inlbuf1, sizeof(__u32));
        if (type & LL_STATFS_LMV)
                exp = sbi->ll_md_exp;
        else if (type & LL_STATFS_LOV)
                exp = sbi->ll_dt_exp;
        else
                GOTO(out_statfs, rc = -ENODEV);

        rc = obd_iocontrol(IOC_OBD_STATFS, exp, len, data, NULL);
        if (rc)
                GOTO(out_statfs, rc);
out_statfs:
        OBD_FREE_LARGE(data, len);
        return rc;
}

/*
 * this is normally called in ll_fini_md_op_data(), but sometimes it needs to
 * be called early to avoid deadlock.
 */
void ll_unlock_md_op_lsm(struct md_op_data *op_data)
{
        if (op_data->op_mea2_sem) {
                up_read_non_owner(op_data->op_mea2_sem);
                op_data->op_mea2_sem = NULL;
        }

        if (op_data->op_mea1_sem) {
                up_read_non_owner(op_data->op_mea1_sem);
                op_data->op_mea1_sem = NULL;
        }
}

/* this function prepares md_op_data hint for passing it down to MD stack. */
struct md_op_data *ll_prep_md_op_data(struct md_op_data *op_data,
                                      struct inode *i1, struct inode *i2,
                                      const char *name, size_t namelen,
                                      __u32 mode, enum md_op_code opc,
                                      void *data)
{
        LASSERT(i1 != NULL);

        if (name == NULL) {
                /* Do not reuse namelen for something else. */
                if (namelen != 0)
                        return ERR_PTR(-EINVAL);
        } else {
                if (namelen > ll_i2sbi(i1)->ll_namelen)
                        return ERR_PTR(-ENAMETOOLONG);

                /* "/" is not valid name, but it's allowed */
                if (!lu_name_is_valid_2(name, namelen) &&
                    strncmp("/", name, namelen) != 0)
                        return ERR_PTR(-EINVAL);
        }

        if (op_data == NULL)
                OBD_ALLOC_PTR(op_data);

        if (op_data == NULL)
                return ERR_PTR(-ENOMEM);

        ll_i2gids(op_data->op_suppgids, i1, i2);
        op_data->op_fid1 = *ll_inode2fid(i1);
        op_data->op_code = opc;

        if (S_ISDIR(i1->i_mode)) {
                down_read_non_owner(&ll_i2info(i1)->lli_lsm_sem);
                op_data->op_mea1_sem = &ll_i2info(i1)->lli_lsm_sem;
                op_data->op_mea1 = ll_i2info(i1)->lli_lsm_md;
                op_data->op_default_mea1 = ll_i2info(i1)->lli_default_lsm_md;
        }

        if (i2) {
                op_data->op_fid2 = *ll_inode2fid(i2);
                if (S_ISDIR(i2->i_mode)) {
                        if (i2 != i1) {
                                /* i2 is typically a child of i1, and MUST be
                                 * further from the root to avoid deadlocks.
                                 */
                                down_read_non_owner(&ll_i2info(i2)->lli_lsm_sem);
                                op_data->op_mea2_sem =
                                                &ll_i2info(i2)->lli_lsm_sem;
                        }
                        op_data->op_mea2 = ll_i2info(i2)->lli_lsm_md;
                }
        } else {
                fid_zero(&op_data->op_fid2);
        }

        if (ll_i2sbi(i1)->ll_flags & LL_SBI_64BIT_HASH)
                op_data->op_cli_flags |= CLI_HASH64;

        if (ll_need_32bit_api(ll_i2sbi(i1)))
                op_data->op_cli_flags |= CLI_API32;

        op_data->op_name = name;
        op_data->op_namelen = namelen;
        op_data->op_mode = mode;
        op_data->op_mod_time = ktime_get_real_seconds();
        op_data->op_fsuid = from_kuid(&init_user_ns, current_fsuid());
        op_data->op_fsgid = from_kgid(&init_user_ns, current_fsgid());
        op_data->op_cap = cfs_curproc_cap_pack();
        op_data->op_mds = 0;
        if ((opc == LUSTRE_OPC_CREATE) && (name != NULL) &&
             filename_is_volatile(name, namelen, &op_data->op_mds)) {
                op_data->op_bias |= MDS_CREATE_VOLATILE;
        }
        op_data->op_data = data;

        return op_data;
}

void ll_finish_md_op_data(struct md_op_data *op_data)
{
        ll_unlock_md_op_lsm(op_data);
        security_release_secctx(op_data->op_file_secctx,
                                op_data->op_file_secctx_size);
        llcrypt_free_ctx(op_data->op_file_encctx, op_data->op_file_encctx_size);
        OBD_FREE_PTR(op_data);
}

int ll_show_options(struct seq_file *seq, struct dentry *dentry)
{
        struct ll_sb_info *sbi;

        LASSERT(seq && dentry);
        sbi = ll_s2sbi(dentry->d_sb);

        if (sbi->ll_flags & LL_SBI_NOLCK)
                seq_puts(seq, ",nolock");

        /* "flock" is the default since 2.13, but it wasn't for many years,
         * so it is still useful to print this to show it is enabled.
         * Start to print "noflock" so it is now clear when flock is disabled.
         */
        if (sbi->ll_flags & LL_SBI_FLOCK)
                seq_puts(seq, ",flock");
        else if (sbi->ll_flags & LL_SBI_LOCALFLOCK)
                seq_puts(seq, ",localflock");
        else
                seq_puts(seq, ",noflock");

        if (sbi->ll_flags & LL_SBI_USER_XATTR)
                seq_puts(seq, ",user_xattr");

        if (sbi->ll_flags & LL_SBI_LAZYSTATFS)
                seq_puts(seq, ",lazystatfs");

        if (sbi->ll_flags & LL_SBI_USER_FID2PATH)
                seq_puts(seq, ",user_fid2path");

        if (sbi->ll_flags & LL_SBI_ALWAYS_PING)
                seq_puts(seq, ",always_ping");

        if (ll_sbi_has_test_dummy_encryption(sbi))
                seq_puts(seq, ",test_dummy_encryption");

        if (ll_sbi_has_encrypt(sbi))
                seq_puts(seq, ",encrypt");
        else
                seq_puts(seq, ",noencrypt");

        if (sbi->ll_flags & LL_SBI_FOREIGN_SYMLINK) {
                seq_puts(seq, ",foreign_symlink=");
                seq_puts(seq, sbi->ll_foreign_symlink_prefix);
        }

        RETURN(0);
}

/**
 * Get obd name by cmd, and copy out to user space
 */
int ll_get_obd_name(struct inode *inode, unsigned int cmd, unsigned long arg)
{
        struct ll_sb_info *sbi = ll_i2sbi(inode);
        struct obd_device *obd;
        ENTRY;

        if (cmd == OBD_IOC_GETNAME_OLD || cmd == OBD_IOC_GETDTNAME)
                obd = class_exp2obd(sbi->ll_dt_exp);
        else if (cmd == OBD_IOC_GETMDNAME)
                obd = class_exp2obd(sbi->ll_md_exp);
        else
                RETURN(-EINVAL);

        if (!obd)
                RETURN(-ENOENT);

        if (copy_to_user((void __user *)arg, obd->obd_name,
                         strlen(obd->obd_name) + 1))
                RETURN(-EFAULT);

        RETURN(0);
}

static char* ll_d_path(struct dentry *dentry, char *buf, int bufsize)
{
        char *path = NULL;

        struct path p;

        p.dentry = dentry;
        p.mnt = current->fs->root.mnt;
        path_get(&p);
        path = d_path(&p, buf, bufsize);
        path_put(&p);
        return path;
}

void ll_dirty_page_discard_warn(struct page *page, int ioret)
{
        char *buf, *path = NULL;
        struct dentry *dentry = NULL;
        struct inode *inode = page->mapping->host;

        /* this can be called inside spin lock so use GFP_ATOMIC. */
        buf = (char *)__get_free_page(GFP_ATOMIC);
        if (buf != NULL) {
                dentry = d_find_alias(page->mapping->host);
                if (dentry != NULL)
                        path = ll_d_path(dentry, buf, PAGE_SIZE);
        }

        /* The below message is checked in recovery-small.sh test_24b */
        CDEBUG(D_WARNING,
               "%s: dirty page discard: %s/fid: "DFID"/%s may get corrupted "
               "(rc %d)\n", ll_i2sbi(inode)->ll_fsname,
               s2lsi(page->mapping->host->i_sb)->lsi_lmd->lmd_dev,
               PFID(ll_inode2fid(inode)),
               (path && !IS_ERR(path)) ? path : "", ioret);

        if (dentry != NULL)
                dput(dentry);

        if (buf != NULL)
                free_page((unsigned long)buf);
}

ssize_t ll_copy_user_md(const struct lov_user_md __user *md,
                        struct lov_user_md **kbuf)
{
        struct lov_user_md      lum;
        ssize_t                 lum_size;
        ENTRY;

        if (copy_from_user(&lum, md, sizeof(lum)))
                RETURN(-EFAULT);

        lum_size = ll_lov_user_md_size(&lum);
        if (lum_size < 0)
                RETURN(lum_size);

        OBD_ALLOC_LARGE(*kbuf, lum_size);
        if (*kbuf == NULL)
                RETURN(-ENOMEM);

        if (copy_from_user(*kbuf, md, lum_size) != 0) {
                OBD_FREE_LARGE(*kbuf, lum_size);
                RETURN(-EFAULT);
        }

        RETURN(lum_size);
}

/*
 * Compute llite root squash state after a change of root squash
 * configuration setting or add/remove of a lnet nid
 */
void ll_compute_rootsquash_state(struct ll_sb_info *sbi)
{
        struct root_squash_info *squash = &sbi->ll_squash;
        int i;
        bool matched;
        struct lnet_process_id id;

        /* Update norootsquash flag */
        spin_lock(&squash->rsi_lock);
        if (list_empty(&squash->rsi_nosquash_nids))
                sbi->ll_flags &= ~LL_SBI_NOROOTSQUASH;
        else {
                /* Do not apply root squash as soon as one of our NIDs is
                 * in the nosquash_nids list */
                matched = false;
                i = 0;
                while (LNetGetId(i++, &id) != -ENOENT) {
                        if (id.nid == LNET_NID_LO_0)
                                continue;
                        if (cfs_match_nid(id.nid, &squash->rsi_nosquash_nids)) {
                                matched = true;
                                break;
                        }
                }
                if (matched)
                        sbi->ll_flags |= LL_SBI_NOROOTSQUASH;
                else
                        sbi->ll_flags &= ~LL_SBI_NOROOTSQUASH;
        }
        spin_unlock(&squash->rsi_lock);
}

/**
 * Parse linkea content to extract information about a given hardlink
 *
 * \param[in]   ldata      - Initialized linkea data
 * \param[in]   linkno     - Link identifier
 * \param[out]  parent_fid - The entry's parent FID
 * \param[out]  ln         - Entry name destination buffer
 *
 * \retval 0 on success
 * \retval Appropriate negative error code on failure
 */
static int ll_linkea_decode(struct linkea_data *ldata, unsigned int linkno,
                            struct lu_fid *parent_fid, struct lu_name *ln)
{
        unsigned int    idx;
        int             rc;
        ENTRY;

        rc = linkea_init_with_rec(ldata);
        if (rc < 0)
                RETURN(rc);

        if (linkno >= ldata->ld_leh->leh_reccount)
                /* beyond last link */
                RETURN(-ENODATA);

        linkea_first_entry(ldata);
        for (idx = 0; ldata->ld_lee != NULL; idx++) {
                linkea_entry_unpack(ldata->ld_lee, &ldata->ld_reclen, ln,
                                    parent_fid);
                if (idx == linkno)
                        break;

                linkea_next_entry(ldata);
        }

        if (idx < linkno)
                RETURN(-ENODATA);

        RETURN(0);
}

/**
 * Get parent FID and name of an identified link. Operation is performed for
 * a given link number, letting the caller iterate over linkno to list one or
 * all links of an entry.
 *
 * \param[in]     file - File descriptor against which to perform the operation
 * \param[in,out] arg  - User-filled structure containing the linkno to operate
 *                       on and the available size. It is eventually filled with
 *                       the requested information or left untouched on error
 *
 * \retval - 0 on success
 * \retval - Appropriate negative error code on failure
 */
int ll_getparent(struct file *file, struct getparent __user *arg)
{
        struct inode            *inode = file_inode(file);
        struct linkea_data      *ldata;
        struct lu_buf            buf = LU_BUF_NULL;
        struct lu_name           ln;
        struct lu_fid            parent_fid;
        __u32                    linkno;
        __u32                    name_size;
        int                      rc;

        ENTRY;

        if (!capable(CAP_DAC_READ_SEARCH) &&
            !(ll_i2sbi(inode)->ll_flags & LL_SBI_USER_FID2PATH))
                RETURN(-EPERM);

        if (get_user(name_size, &arg->gp_name_size))
                RETURN(-EFAULT);

        if (get_user(linkno, &arg->gp_linkno))
                RETURN(-EFAULT);

        if (name_size > PATH_MAX)
                RETURN(-EINVAL);

        OBD_ALLOC(ldata, sizeof(*ldata));
        if (ldata == NULL)
                RETURN(-ENOMEM);

        rc = linkea_data_new(ldata, &buf);
        if (rc < 0)
                GOTO(ldata_free, rc);

        rc = ll_xattr_list(inode, XATTR_NAME_LINK, XATTR_TRUSTED_T, buf.lb_buf,
                           buf.lb_len, OBD_MD_FLXATTR);
        if (rc < 0)
                GOTO(lb_free, rc);

        rc = ll_linkea_decode(ldata, linkno, &parent_fid, &ln);
        if (rc < 0)
                GOTO(lb_free, rc);

        if (ln.ln_namelen >= name_size)
                GOTO(lb_free, rc = -EOVERFLOW);

        if (copy_to_user(&arg->gp_fid, &parent_fid, sizeof(arg->gp_fid)))
                GOTO(lb_free, rc = -EFAULT);

        if (copy_to_user(&arg->gp_name, ln.ln_name, ln.ln_namelen))
                GOTO(lb_free, rc = -EFAULT);

        if (put_user('\0', arg->gp_name + ln.ln_namelen))
                GOTO(lb_free, rc = -EFAULT);

lb_free:
        lu_buf_free(&buf);
ldata_free:
        OBD_FREE(ldata, sizeof(*ldata));

        RETURN(rc);
}