// SPDX-License-Identifier: GPL-2.0
/*
 * 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) 2002, 2010, Oracle and/or its affiliates. All rights reserved.
 * Use is subject to license terms.
 *
 * Copyright (c) 2011, 2015, Intel Corporation.
 */
/*
 * This file is part of Lustre, http://www.lustre.org/
 * Lustre is a trademark of Sun Microsystems, Inc.
 */
#define DEBUG_SUBSYSTEM S_CLASS

#include <obd_support.h>
#include <obd.h>
#include <lprocfs_status.h>
#include <uapi/linux/lustre/lustre_idl.h>
#include <lustre_net.h>
#include <obd_class.h>
#include "ptlrpc_internal.h"

static struct ll_rpc_opcode {
        __u32       opcode;
        const char *opname;
} ll_rpc_opcode_table[LUSTRE_MAX_OPCODES] = {
        { OST_REPLY,    "ost_reply" },
        { OST_GETATTR,      "ost_getattr" },
        { OST_SETATTR,      "ost_setattr" },
        { OST_READ,      "ost_read" },
        { OST_WRITE,    "ost_write" },
        { OST_CREATE,       "ost_create" },
        { OST_DESTROY,      "ost_destroy" },
        { OST_GET_INFO,     "ost_get_info" },
        { OST_CONNECT,      "ost_connect" },
        { OST_DISCONNECT,   "ost_disconnect" },
        { OST_PUNCH,    "ost_punch" },
        { OST_OPEN,      "ost_open" },
        { OST_CLOSE,    "ost_close" },
        { OST_STATFS,       "ost_statfs" },
        { 14,           NULL },    /* formerly OST_SAN_READ */
        { 15,           NULL },    /* formerly OST_SAN_WRITE */
        { OST_SYNC,      "ost_sync" },
        { OST_SET_INFO,     "ost_set_info" },
        { OST_QUOTACHECK,   "ost_quotacheck" },
        { OST_QUOTACTL,     "ost_quotactl" },
        { OST_QUOTA_ADJUST_QUNIT, "ost_quota_adjust_qunit" },
        { MDS_GETATTR,      "mds_getattr" },
        { MDS_GETATTR_NAME, "mds_getattr_lock" },
        { MDS_CLOSE,    "mds_close" },
        { MDS_REINT,    "mds_reint" },
        { MDS_READPAGE,     "mds_readpage" },
        { MDS_CONNECT,      "mds_connect" },
        { MDS_DISCONNECT,   "mds_disconnect" },
        { MDS_GETSTATUS,    "mds_getstatus" },
        { MDS_STATFS,       "mds_statfs" },
        { MDS_PIN,        "mds_pin" },
        { MDS_UNPIN,    "mds_unpin" },
        { MDS_SYNC,      "mds_sync" },
        { MDS_DONE_WRITING, "mds_done_writing" },
        { MDS_SET_INFO,     "mds_set_info" },
        { MDS_QUOTACHECK,   "mds_quotacheck" },
        { MDS_QUOTACTL,     "mds_quotactl" },
        { MDS_GETXATTR,     "mds_getxattr" },
        { MDS_SETXATTR,     "mds_setxattr" },
        { MDS_WRITEPAGE,    "mds_writepage" },
        { MDS_IS_SUBDIR,    "mds_is_subdir" },
        { MDS_GET_INFO,     "mds_get_info" },
        { MDS_HSM_STATE_GET, "mds_hsm_state_get" },
        { MDS_HSM_STATE_SET, "mds_hsm_state_set" },
        { MDS_HSM_ACTION,   "mds_hsm_action" },
        { MDS_HSM_PROGRESS, "mds_hsm_progress" },
        { MDS_HSM_REQUEST,  "mds_hsm_request" },
        { MDS_HSM_CT_REGISTER, "mds_hsm_ct_register" },
        { MDS_HSM_CT_UNREGISTER, "mds_hsm_ct_unregister" },
        { MDS_SWAP_LAYOUTS,     "mds_swap_layouts" },
        { LDLM_ENQUEUE,     "ldlm_enqueue" },
        { LDLM_CONVERT,     "ldlm_convert" },
        { LDLM_CANCEL,      "ldlm_cancel" },
        { LDLM_BL_CALLBACK, "ldlm_bl_callback" },
        { LDLM_CP_CALLBACK, "ldlm_cp_callback" },
        { LDLM_GL_CALLBACK, "ldlm_gl_callback" },
        { LDLM_SET_INFO,    "ldlm_set_info" },
        { MGS_CONNECT,      "mgs_connect" },
        { MGS_DISCONNECT,   "mgs_disconnect" },
        { MGS_EXCEPTION,    "mgs_exception" },
        { MGS_TARGET_REG,   "mgs_target_reg" },
        { MGS_TARGET_DEL,   "mgs_target_del" },
        { MGS_SET_INFO,     "mgs_set_info" },
        { MGS_CONFIG_READ,  "mgs_config_read" },
        { OBD_PING,      "obd_ping" },
        { OBD_LOG_CANCEL,       "llog_cancel" },
        { OBD_QC_CALLBACK,  "obd_quota_callback" },
        { OBD_IDX_READ,     "dt_index_read" },
        { LLOG_ORIGIN_HANDLE_CREATE,     "llog_origin_handle_open" },
        { LLOG_ORIGIN_HANDLE_NEXT_BLOCK, "llog_origin_handle_next_block" },
        { LLOG_ORIGIN_HANDLE_READ_HEADER, "llog_origin_handle_read_header" },
        { LLOG_ORIGIN_HANDLE_WRITE_REC,  "llog_origin_handle_write_rec" },
        { LLOG_ORIGIN_HANDLE_CLOSE,      "llog_origin_handle_close" },
        { LLOG_ORIGIN_CONNECT,     "llog_origin_connect" },
        { LLOG_CATINFO,           "llog_catinfo" },
        { LLOG_ORIGIN_HANDLE_PREV_BLOCK, "llog_origin_handle_prev_block" },
        { LLOG_ORIGIN_HANDLE_DESTROY,    "llog_origin_handle_destroy" },
        { QUOTA_DQACQ,      "quota_acquire" },
        { QUOTA_DQREL,      "quota_release" },
        { SEQ_QUERY,    "seq_query" },
        { SEC_CTX_INIT,     "sec_ctx_init" },
        { SEC_CTX_INIT_CONT, "sec_ctx_init_cont" },
        { SEC_CTX_FINI,     "sec_ctx_fini" },
        { FLD_QUERY,    "fld_query" },
        { FLD_READ,     "fld_read" },
};

static struct ll_eopcode {
        __u32       opcode;
        const char *opname;
} ll_eopcode_table[EXTRA_LAST_OPC] = {
        { LDLM_GLIMPSE_ENQUEUE, "ldlm_glimpse_enqueue" },
        { LDLM_PLAIN_ENQUEUE,   "ldlm_plain_enqueue" },
        { LDLM_EXTENT_ENQUEUE,  "ldlm_extent_enqueue" },
        { LDLM_FLOCK_ENQUEUE,   "ldlm_flock_enqueue" },
        { LDLM_IBITS_ENQUEUE,   "ldlm_ibits_enqueue" },
        { MDS_REINT_SETATTR,    "mds_reint_setattr" },
        { MDS_REINT_CREATE,     "mds_reint_create" },
        { MDS_REINT_LINK,       "mds_reint_link" },
        { MDS_REINT_UNLINK,     "mds_reint_unlink" },
        { MDS_REINT_RENAME,     "mds_reint_rename" },
        { MDS_REINT_OPEN,       "mds_reint_open" },
        { MDS_REINT_SETXATTR,   "mds_reint_setxattr" },
        { BRW_READ_BYTES,       "read_bytes" },
        { BRW_WRITE_BYTES,      "write_bytes" },
};

const char *ll_opcode2str(__u32 opcode)
{
        /* When one of the assertions below fail, chances are that:
         *     1) A new opcode was added in include/lustre/lustre_idl.h,
         *      but is missing from the table above.
         * or  2) The opcode space was renumbered or rearranged,
         *      and the opcode_offset() function in
         *      ptlrpc_internal.h needs to be modified.
         */
        __u32 offset = opcode_offset(opcode);

        LASSERTF(offset < LUSTRE_MAX_OPCODES,
                 "offset %u >= LUSTRE_MAX_OPCODES %u\n",
                 offset, LUSTRE_MAX_OPCODES);
        LASSERTF(ll_rpc_opcode_table[offset].opcode == opcode,
                 "ll_rpc_opcode_table[%u].opcode %u != opcode %u\n",
                 offset, ll_rpc_opcode_table[offset].opcode, opcode);
        return ll_rpc_opcode_table[offset].opname;
}

static const char *ll_eopcode2str(__u32 opcode)
{
        LASSERT(ll_eopcode_table[opcode].opcode == opcode);
        return ll_eopcode_table[opcode].opname;
}

static void
ptlrpc_ldebugfs_register(struct dentry *root, char *dir,
                         char *name,
                         struct dentry **debugfs_root_ret,
                         struct lprocfs_stats **stats_ret)
{
        struct dentry *svc_debugfs_entry;
        struct lprocfs_stats *svc_stats;
        int i, rc;
        unsigned int svc_counter_config = LPROCFS_CNTR_AVGMINMAX |
                                          LPROCFS_CNTR_STDDEV;

        LASSERT(!*debugfs_root_ret);
        LASSERT(!*stats_ret);

        svc_stats = lprocfs_alloc_stats(EXTRA_MAX_OPCODES + LUSTRE_MAX_OPCODES,
                                        0);
        if (!svc_stats)
                return;

        if (dir) {
                svc_debugfs_entry = ldebugfs_register(dir, root, NULL, NULL);
                if (IS_ERR(svc_debugfs_entry)) {
                        lprocfs_free_stats(&svc_stats);
                        return;
                }
        } else {
                svc_debugfs_entry = root;
        }

        lprocfs_counter_init(svc_stats, PTLRPC_REQWAIT_CNTR,
                             svc_counter_config, "req_waittime", "usec");
        lprocfs_counter_init(svc_stats, PTLRPC_REQQDEPTH_CNTR,
                             svc_counter_config, "req_qdepth", "reqs");
        lprocfs_counter_init(svc_stats, PTLRPC_REQACTIVE_CNTR,
                             svc_counter_config, "req_active", "reqs");
        lprocfs_counter_init(svc_stats, PTLRPC_TIMEOUT,
                             svc_counter_config, "req_timeout", "sec");
        lprocfs_counter_init(svc_stats, PTLRPC_REQBUF_AVAIL_CNTR,
                             svc_counter_config, "reqbuf_avail", "bufs");
        for (i = 0; i < EXTRA_LAST_OPC; i++) {
                char *units;

                switch (i) {
                case BRW_WRITE_BYTES:
                case BRW_READ_BYTES:
                        units = "bytes";
                        break;
                default:
                        units = "reqs";
                        break;
                }
                lprocfs_counter_init(svc_stats, PTLRPC_LAST_CNTR + i,
                                     svc_counter_config,
                                     ll_eopcode2str(i), units);
        }
        for (i = 0; i < LUSTRE_MAX_OPCODES; i++) {
                __u32 opcode = ll_rpc_opcode_table[i].opcode;

                lprocfs_counter_init(svc_stats,
                                     EXTRA_MAX_OPCODES + i, svc_counter_config,
                                     ll_opcode2str(opcode), "usec");
        }

        rc = ldebugfs_register_stats(svc_debugfs_entry, name, svc_stats);
        if (rc < 0) {
                if (dir)
                        ldebugfs_remove(&svc_debugfs_entry);
                lprocfs_free_stats(&svc_stats);
        } else {
                if (dir)
                        *debugfs_root_ret = svc_debugfs_entry;
                *stats_ret = svc_stats;
        }
}

static int
ptlrpc_lprocfs_req_history_len_seq_show(struct seq_file *m, void *v)
{
        struct ptlrpc_service *svc = m->private;
        struct ptlrpc_service_part *svcpt;
        int total = 0;
        int i;

        ptlrpc_service_for_each_part(svcpt, i, svc)
                total += svcpt->scp_hist_nrqbds;

        seq_printf(m, "%d\n", total);
        return 0;
}

LPROC_SEQ_FOPS_RO(ptlrpc_lprocfs_req_history_len);

static int
ptlrpc_lprocfs_req_history_max_seq_show(struct seq_file *m, void *n)
{
        struct ptlrpc_service *svc = m->private;
        struct ptlrpc_service_part *svcpt;
        int total = 0;
        int i;

        ptlrpc_service_for_each_part(svcpt, i, svc)
                total += svc->srv_hist_nrqbds_cpt_max;

        seq_printf(m, "%d\n", total);
        return 0;
}

static ssize_t
ptlrpc_lprocfs_req_history_max_seq_write(struct file *file,
                                         const char __user *buffer,
                                         size_t count, loff_t *off)
{
        struct ptlrpc_service *svc = ((struct seq_file *)file->private_data)->private;
        int bufpages;
        int val;
        int rc;

        rc = lprocfs_write_helper(buffer, count, &val);
        if (rc < 0)
                return rc;

        if (val < 0)
                return -ERANGE;

        /* This sanity check is more of an insanity check; we can still
         * hose a kernel by allowing the request history to grow too
         * far.
         */
        bufpages = (svc->srv_buf_size + PAGE_SIZE - 1) >> PAGE_SHIFT;
        if (val > totalram_pages / (2 * bufpages))
                return -ERANGE;

        spin_lock(&svc->srv_lock);

        if (val == 0)
                svc->srv_hist_nrqbds_cpt_max = 0;
        else
                svc->srv_hist_nrqbds_cpt_max = max(1, (val / svc->srv_ncpts));

        spin_unlock(&svc->srv_lock);

        return count;
}

LPROC_SEQ_FOPS(ptlrpc_lprocfs_req_history_max);

static ssize_t threads_min_show(struct kobject *kobj, struct attribute *attr,
                                char *buf)
{
        struct ptlrpc_service *svc = container_of(kobj, struct ptlrpc_service,
                                                  srv_kobj);

        return sprintf(buf, "%d\n", svc->srv_nthrs_cpt_init * svc->srv_ncpts);
}

static ssize_t threads_min_store(struct kobject *kobj, struct attribute *attr,
                                 const char *buffer, size_t count)
{
        struct ptlrpc_service *svc = container_of(kobj, struct ptlrpc_service,
                                                  srv_kobj);
        unsigned long val;
        int rc = kstrtoul(buffer, 10, &val);

        if (rc < 0)
                return rc;

        if (val / svc->srv_ncpts < PTLRPC_NTHRS_INIT)
                return -ERANGE;

        spin_lock(&svc->srv_lock);
        if (val > svc->srv_nthrs_cpt_limit * svc->srv_ncpts) {
                spin_unlock(&svc->srv_lock);
                return -ERANGE;
        }

        svc->srv_nthrs_cpt_init = val / svc->srv_ncpts;

        spin_unlock(&svc->srv_lock);

        return count;
}
LUSTRE_RW_ATTR(threads_min);

static ssize_t threads_started_show(struct kobject *kobj,
                                    struct attribute *attr,
                                    char *buf)
{
        struct ptlrpc_service *svc = container_of(kobj, struct ptlrpc_service,
                                                  srv_kobj);
        struct ptlrpc_service_part *svcpt;
        int total = 0;
        int i;

        ptlrpc_service_for_each_part(svcpt, i, svc)
                total += svcpt->scp_nthrs_running;

        return sprintf(buf, "%d\n", total);
}
LUSTRE_RO_ATTR(threads_started);

static ssize_t threads_max_show(struct kobject *kobj, struct attribute *attr,
                                char *buf)
{
        struct ptlrpc_service *svc = container_of(kobj, struct ptlrpc_service,
                                                  srv_kobj);

        return sprintf(buf, "%d\n", svc->srv_nthrs_cpt_limit * svc->srv_ncpts);
}

static ssize_t threads_max_store(struct kobject *kobj, struct attribute *attr,
                                 const char *buffer, size_t count)
{
        struct ptlrpc_service *svc = container_of(kobj, struct ptlrpc_service,
                                                  srv_kobj);
        unsigned long val;
        int rc = kstrtoul(buffer, 10, &val);

        if (rc < 0)
                return rc;

        if (val / svc->srv_ncpts < PTLRPC_NTHRS_INIT)
                return -ERANGE;

        spin_lock(&svc->srv_lock);
        if (val < svc->srv_nthrs_cpt_init * svc->srv_ncpts) {
                spin_unlock(&svc->srv_lock);
                return -ERANGE;
        }

        svc->srv_nthrs_cpt_limit = val / svc->srv_ncpts;

        spin_unlock(&svc->srv_lock);

        return count;
}
LUSTRE_RW_ATTR(threads_max);

/**
 * \addtogoup nrs
 * @{
 */

/**
 * Translates \e ptlrpc_nrs_pol_state values to human-readable strings.
 *
 * \param[in] state The policy state
 */
static const char *nrs_state2str(enum ptlrpc_nrs_pol_state state)
{
        switch (state) {
        default:
                LBUG();
        case NRS_POL_STATE_INVALID:
                return "invalid";
        case NRS_POL_STATE_STOPPED:
                return "stopped";
        case NRS_POL_STATE_STOPPING:
                return "stopping";
        case NRS_POL_STATE_STARTING:
                return "starting";
        case NRS_POL_STATE_STARTED:
                return "started";
        }
}

/**
 * Obtains status information for \a policy.
 *
 * Information is copied in \a info.
 *
 * \param[in] policy The policy
 * \param[out] info  Holds returned status information
 */
static void nrs_policy_get_info_locked(struct ptlrpc_nrs_policy *policy,
                                       struct ptlrpc_nrs_pol_info *info)
{
        assert_spin_locked(&policy->pol_nrs->nrs_lock);

        memcpy(info->pi_name, policy->pol_desc->pd_name, NRS_POL_NAME_MAX);

        info->pi_fallback    = !!(policy->pol_flags & PTLRPC_NRS_FL_FALLBACK);
        info->pi_state       = policy->pol_state;
        /**
         * XXX: These are accessed without holding
         * ptlrpc_service_part::scp_req_lock.
         */
        info->pi_req_queued  = policy->pol_req_queued;
        info->pi_req_started = policy->pol_req_started;
}

/**
 * Reads and prints policy status information for all policies of a PTLRPC
 * service.
 */
static int ptlrpc_lprocfs_nrs_seq_show(struct seq_file *m, void *n)
{
        struct ptlrpc_service *svc = m->private;
        struct ptlrpc_service_part *svcpt;
        struct ptlrpc_nrs *nrs;
        struct ptlrpc_nrs_policy *policy;
        struct ptlrpc_nrs_pol_info *infos;
        struct ptlrpc_nrs_pol_info tmp;
        unsigned int num_pols;
        unsigned int pol_idx = 0;
        bool hp = false;
        int i;
        int rc = 0;

        /**
         * Serialize NRS core lprocfs operations with policy registration/
         * unregistration.
         */
        mutex_lock(&nrs_core.nrs_mutex);

        /**
         * Use the first service partition's regular NRS head in order to obtain
         * the number of policies registered with NRS heads of this service. All
         * service partitions will have the same number of policies.
         */
        nrs = nrs_svcpt2nrs(svc->srv_parts[0], false);

        spin_lock(&nrs->nrs_lock);
        num_pols = svc->srv_parts[0]->scp_nrs_reg.nrs_num_pols;
        spin_unlock(&nrs->nrs_lock);

        infos = kcalloc(num_pols, sizeof(*infos), GFP_NOFS);
        if (!infos) {
                rc = -ENOMEM;
                goto unlock;
        }
again:

        ptlrpc_service_for_each_part(svcpt, i, svc) {
                nrs = nrs_svcpt2nrs(svcpt, hp);
                spin_lock(&nrs->nrs_lock);

                pol_idx = 0;

                list_for_each_entry(policy, &nrs->nrs_policy_list, pol_list) {
                        LASSERT(pol_idx < num_pols);

                        nrs_policy_get_info_locked(policy, &tmp);
                        /**
                         * Copy values when handling the first service
                         * partition.
                         */
                        if (i == 0) {
                                memcpy(infos[pol_idx].pi_name, tmp.pi_name,
                                       NRS_POL_NAME_MAX);
                                memcpy(&infos[pol_idx].pi_state, &tmp.pi_state,
                                       sizeof(tmp.pi_state));
                                infos[pol_idx].pi_fallback = tmp.pi_fallback;
                                /**
                                 * For the rest of the service partitions
                                 * sanity-check the values we get.
                                 */
                        } else {
                                LASSERT(strncmp(infos[pol_idx].pi_name,
                                                tmp.pi_name,
                                                NRS_POL_NAME_MAX) == 0);
                                /**
                                 * Not asserting ptlrpc_nrs_pol_info::pi_state,
                                 * because it may be different between
                                 * instances of the same policy in different
                                 * service partitions.
                                 */
                                LASSERT(infos[pol_idx].pi_fallback ==
                                        tmp.pi_fallback);
                        }

                        infos[pol_idx].pi_req_queued += tmp.pi_req_queued;
                        infos[pol_idx].pi_req_started += tmp.pi_req_started;

                        pol_idx++;
                }
                spin_unlock(&nrs->nrs_lock);
        }

        /**
         * Policy status information output is in YAML format.
         * For example:
         *
         *      regular_requests:
         *        - name: fifo
         *          state: started
         *          fallback: yes
         *          queued: 0
         *          active: 0
         *
         *        - name: crrn
         *          state: started
         *          fallback: no
         *          queued: 2015
         *          active: 384
         *
         *      high_priority_requests:
         *        - name: fifo
         *          state: started
         *          fallback: yes
         *          queued: 0
         *          active: 2
         *
         *        - name: crrn
         *          state: stopped
         *          fallback: no
         *          queued: 0
         *          active: 0
         */
        seq_printf(m, "%s\n",
                   !hp ?  "\nregular_requests:" : "high_priority_requests:");

        for (pol_idx = 0; pol_idx < num_pols; pol_idx++) {
                seq_printf(m,  "  - name: %s\n"
                               "    state: %s\n"
                               "    fallback: %s\n"
                               "    queued: %-20d\n"
                               "    active: %-20d\n\n",
                               infos[pol_idx].pi_name,
                               nrs_state2str(infos[pol_idx].pi_state),
                               infos[pol_idx].pi_fallback ? "yes" : "no",
                               (int)infos[pol_idx].pi_req_queued,
                               (int)infos[pol_idx].pi_req_started);
        }

        if (!hp && nrs_svc_has_hp(svc)) {
                memset(infos, 0, num_pols * sizeof(*infos));

                /**
                 * Redo the processing for the service's HP NRS heads' policies.
                 */
                hp = true;
                goto again;
        }

        kfree(infos);
unlock:
        mutex_unlock(&nrs_core.nrs_mutex);

        return rc;
}

/**
 * The longest valid command string is the maximum policy name size, plus the
 * length of the " reg" substring
 */
#define LPROCFS_NRS_WR_MAX_CMD  (NRS_POL_NAME_MAX + sizeof(" reg") - 1)

/**
 * Starts and stops a given policy on a PTLRPC service.
 *
 * Commands consist of the policy name, followed by an optional [reg|hp] token;
 * if the optional token is omitted, the operation is performed on both the
 * regular and high-priority (if the service has one) NRS head.
 */
static ssize_t ptlrpc_lprocfs_nrs_seq_write(struct file *file,
                                            const char __user *buffer,
                                            size_t count, loff_t *off)
{
        struct ptlrpc_service *svc = ((struct seq_file *)file->private_data)->private;
        enum ptlrpc_nrs_queue_type queue = PTLRPC_NRS_QUEUE_BOTH;
        char *cmd;
        char *cmd_copy = NULL;
        char *token;
        int rc = 0;

        if (count >= LPROCFS_NRS_WR_MAX_CMD)
                return -EINVAL;

        cmd = kzalloc(LPROCFS_NRS_WR_MAX_CMD, GFP_NOFS);
        if (!cmd)
                return -ENOMEM;
        /**
         * strsep() modifies its argument, so keep a copy
         */
        cmd_copy = cmd;

        if (copy_from_user(cmd, buffer, count)) {
                rc = -EFAULT;
                goto out;
        }

        cmd[count] = '\0';

        token = strsep(&cmd, " ");

        if (strlen(token) > NRS_POL_NAME_MAX - 1) {
                rc = -EINVAL;
                goto out;
        }

        /**
         * No [reg|hp] token has been specified
         */
        if (!cmd)
                goto default_queue;

        /**
         * The second token is either NULL, or an optional [reg|hp] string
         */
        if (strcmp(cmd, "reg") == 0) {
                queue = PTLRPC_NRS_QUEUE_REG;
        } else if (strcmp(cmd, "hp") == 0) {
                queue = PTLRPC_NRS_QUEUE_HP;
        } else {
                rc = -EINVAL;
                goto out;
        }

default_queue:

        if (queue == PTLRPC_NRS_QUEUE_HP && !nrs_svc_has_hp(svc)) {
                rc = -ENODEV;
                goto out;
        } else if (queue == PTLRPC_NRS_QUEUE_BOTH && !nrs_svc_has_hp(svc)) {
                queue = PTLRPC_NRS_QUEUE_REG;
        }

        /**
         * Serialize NRS core lprocfs operations with policy registration/
         * unregistration.
         */
        mutex_lock(&nrs_core.nrs_mutex);

        rc = ptlrpc_nrs_policy_control(svc, queue, token, PTLRPC_NRS_CTL_START,
                                       false, NULL);

        mutex_unlock(&nrs_core.nrs_mutex);
out:
        kfree(cmd_copy);

        return rc < 0 ? rc : count;
}

LPROC_SEQ_FOPS(ptlrpc_lprocfs_nrs);

/** @} nrs */

struct ptlrpc_srh_iterator {
        int                     srhi_idx;
        __u64                   srhi_seq;
        struct ptlrpc_request   *srhi_req;
};

static int
ptlrpc_lprocfs_svc_req_history_seek(struct ptlrpc_service_part *svcpt,
                                    struct ptlrpc_srh_iterator *srhi,
                                    __u64 seq)
{
        struct list_head *e;
        struct ptlrpc_request *req;

        if (srhi->srhi_req && srhi->srhi_seq > svcpt->scp_hist_seq_culled &&
            srhi->srhi_seq <= seq) {
                /* If srhi_req was set previously, hasn't been culled and
                 * we're searching for a seq on or after it (i.e. more
                 * recent), search from it onwards.
                 * Since the service history is LRU (i.e. culled reqs will
                 * be near the head), we shouldn't have to do long
                 * re-scans
                 */
                LASSERTF(srhi->srhi_seq == srhi->srhi_req->rq_history_seq,
                         "%s:%d: seek seq %llu, request seq %llu\n",
                         svcpt->scp_service->srv_name, svcpt->scp_cpt,
                         srhi->srhi_seq, srhi->srhi_req->rq_history_seq);
                LASSERTF(!list_empty(&svcpt->scp_hist_reqs),
                         "%s:%d: seek offset %llu, request seq %llu, last culled %llu\n",
                         svcpt->scp_service->srv_name, svcpt->scp_cpt,
                         seq, srhi->srhi_seq, svcpt->scp_hist_seq_culled);
                e = &srhi->srhi_req->rq_history_list;
        } else {
                /* search from start */
                e = svcpt->scp_hist_reqs.next;
        }

        while (e != &svcpt->scp_hist_reqs) {
                req = list_entry(e, struct ptlrpc_request, rq_history_list);

                if (req->rq_history_seq >= seq) {
                        srhi->srhi_seq = req->rq_history_seq;
                        srhi->srhi_req = req;
                        return 0;
                }
                e = e->next;
        }

        return -ENOENT;
}

/*
 * ptlrpc history sequence is used as "position" of seq_file, in some case,
 * seq_read() will increase "position" to indicate reading the next
 * element, however, low bits of history sequence are reserved for CPT id
 * (check the details from comments before ptlrpc_req_add_history), which
 * means seq_read() might change CPT id of history sequence and never
 * finish reading of requests on a CPT. To make it work, we have to shift
 * CPT id to high bits and timestamp to low bits, so seq_read() will only
 * increase timestamp which can correctly indicate the next position.
 */

/* convert seq_file pos to cpt */
#define PTLRPC_REQ_POS2CPT(svc, pos)                    \
        ((svc)->srv_cpt_bits == 0 ? 0 :                 \
         (__u64)(pos) >> (64 - (svc)->srv_cpt_bits))

/* make up seq_file pos from cpt */
#define PTLRPC_REQ_CPT2POS(svc, cpt)                    \
        ((svc)->srv_cpt_bits == 0 ? 0 :                 \
         (cpt) << (64 - (svc)->srv_cpt_bits))

/* convert sequence to position */
#define PTLRPC_REQ_SEQ2POS(svc, seq)                    \
        ((svc)->srv_cpt_bits == 0 ? (seq) :             \
         ((seq) >> (svc)->srv_cpt_bits) |               \
         ((seq) << (64 - (svc)->srv_cpt_bits)))

/* convert position to sequence */
#define PTLRPC_REQ_POS2SEQ(svc, pos)                    \
        ((svc)->srv_cpt_bits == 0 ? (pos) :             \
         ((__u64)(pos) << (svc)->srv_cpt_bits) |        \
         ((__u64)(pos) >> (64 - (svc)->srv_cpt_bits)))

static void *
ptlrpc_lprocfs_svc_req_history_start(struct seq_file *s, loff_t *pos)
{
        struct ptlrpc_service           *svc = s->private;
        struct ptlrpc_service_part      *svcpt;
        struct ptlrpc_srh_iterator      *srhi;
        unsigned int                    cpt;
        int                             rc;
        int                             i;

        if (sizeof(loff_t) != sizeof(__u64)) { /* can't support */
                CWARN("Failed to read request history because size of loff_t %d can't match size of u64\n",
                      (int)sizeof(loff_t));
                return NULL;
        }

        srhi = kzalloc(sizeof(*srhi), GFP_NOFS);
        if (!srhi)
                return NULL;

        srhi->srhi_seq = 0;
        srhi->srhi_req = NULL;

        cpt = PTLRPC_REQ_POS2CPT(svc, *pos);

        ptlrpc_service_for_each_part(svcpt, i, svc) {
                if (i < cpt) /* skip */
                        continue;
                if (i > cpt) /* make up the lowest position for this CPT */
                        *pos = PTLRPC_REQ_CPT2POS(svc, i);

                spin_lock(&svcpt->scp_lock);
                rc = ptlrpc_lprocfs_svc_req_history_seek(svcpt, srhi,
                                PTLRPC_REQ_POS2SEQ(svc, *pos));
                spin_unlock(&svcpt->scp_lock);
                if (rc == 0) {
                        *pos = PTLRPC_REQ_SEQ2POS(svc, srhi->srhi_seq);
                        srhi->srhi_idx = i;
                        return srhi;
                }
        }

        kfree(srhi);
        return NULL;
}

static void
ptlrpc_lprocfs_svc_req_history_stop(struct seq_file *s, void *iter)
{
        struct ptlrpc_srh_iterator *srhi = iter;

        kfree(srhi);
}

static void *
ptlrpc_lprocfs_svc_req_history_next(struct seq_file *s,
                                    void *iter, loff_t *pos)
{
        struct ptlrpc_service *svc = s->private;
        struct ptlrpc_srh_iterator *srhi = iter;
        struct ptlrpc_service_part *svcpt;
        __u64 seq;
        int rc;
        int i;

        for (i = srhi->srhi_idx; i < svc->srv_ncpts; i++) {
                svcpt = svc->srv_parts[i];

                if (i > srhi->srhi_idx) { /* reset iterator for a new CPT */
                        srhi->srhi_req = NULL;
                        seq = 0;
                        srhi->srhi_seq = 0;
                } else { /* the next sequence */
                        seq = srhi->srhi_seq + (1 << svc->srv_cpt_bits);
                }

                spin_lock(&svcpt->scp_lock);
                rc = ptlrpc_lprocfs_svc_req_history_seek(svcpt, srhi, seq);
                spin_unlock(&svcpt->scp_lock);
                if (rc == 0) {
                        *pos = PTLRPC_REQ_SEQ2POS(svc, srhi->srhi_seq);
                        srhi->srhi_idx = i;
                        return srhi;
                }
        }

        kfree(srhi);
        return NULL;
}

static int ptlrpc_lprocfs_svc_req_history_show(struct seq_file *s, void *iter)
{
        struct ptlrpc_service *svc = s->private;
        struct ptlrpc_srh_iterator *srhi = iter;
        struct ptlrpc_service_part *svcpt;
        struct ptlrpc_request *req;
        int rc;

        LASSERT(srhi->srhi_idx < svc->srv_ncpts);

        svcpt = svc->srv_parts[srhi->srhi_idx];

        spin_lock(&svcpt->scp_lock);

        rc = ptlrpc_lprocfs_svc_req_history_seek(svcpt, srhi, srhi->srhi_seq);

        if (rc == 0) {
                struct timespec64 arrival, sent, arrivaldiff;
                char nidstr[LNET_NIDSTR_SIZE];

                req = srhi->srhi_req;

                libcfs_nid2str_r(req->rq_self, nidstr, sizeof(nidstr));
                arrival.tv_sec = req->rq_arrival_time.tv_sec;
                arrival.tv_nsec = req->rq_arrival_time.tv_nsec;
                sent.tv_sec = req->rq_sent;
                sent.tv_nsec = 0;
                arrivaldiff = timespec64_sub(sent, arrival);

                /* Print common req fields.
                 * CAVEAT EMPTOR: we're racing with the service handler
                 * here.  The request could contain any old crap, so you
                 * must be just as careful as the service's request
                 * parser. Currently I only print stuff here I know is OK
                 * to look at coz it was set up in request_in_callback()!!!
                 */
                seq_printf(s, "%lld:%s:%s:x%llu:%d:%s:%lld.%06lld:%lld.%06llds(%+lld.0s) ",
                           req->rq_history_seq, nidstr,
                           libcfs_id2str(req->rq_peer), req->rq_xid,
                           req->rq_reqlen, ptlrpc_rqphase2str(req),
                           (s64)req->rq_arrival_time.tv_sec,
                           (s64)req->rq_arrival_time.tv_nsec / NSEC_PER_USEC,
                           (s64)arrivaldiff.tv_sec,
                           (s64)(arrivaldiff.tv_nsec / NSEC_PER_USEC),
                           (s64)(req->rq_sent - req->rq_deadline));
                if (!svc->srv_ops.so_req_printer)
                        seq_putc(s, '\n');
                else
                        svc->srv_ops.so_req_printer(s, srhi->srhi_req);
        }

        spin_unlock(&svcpt->scp_lock);
        return rc;
}

static int
ptlrpc_lprocfs_svc_req_history_open(struct inode *inode, struct file *file)
{
        static const struct seq_operations sops = {
                .start = ptlrpc_lprocfs_svc_req_history_start,
                .stop  = ptlrpc_lprocfs_svc_req_history_stop,
                .next  = ptlrpc_lprocfs_svc_req_history_next,
                .show  = ptlrpc_lprocfs_svc_req_history_show,
        };
        struct seq_file *seqf;
        int rc;

        rc = seq_open(file, &sops);
        if (rc)
                return rc;

        seqf = file->private_data;
        seqf->private = inode->i_private;
        return 0;
}

/* See also lprocfs_rd_timeouts */
static int ptlrpc_lprocfs_timeouts_seq_show(struct seq_file *m, void *n)
{
        struct ptlrpc_service *svc = m->private;
        struct ptlrpc_service_part *svcpt;
        struct dhms ts;
        time64_t worstt;
        unsigned int cur;
        unsigned int worst;
        int i;

        if (AT_OFF) {
                seq_printf(m, "adaptive timeouts off, using obd_timeout %u\n",
                           obd_timeout);
                return 0;
        }

        ptlrpc_service_for_each_part(svcpt, i, svc) {
                cur     = at_get(&svcpt->scp_at_estimate);
                worst   = svcpt->scp_at_estimate.at_worst_ever;
                worstt  = svcpt->scp_at_estimate.at_worst_time;
                s2dhms(&ts, ktime_get_real_seconds() - worstt);

                seq_printf(m, "%10s : cur %3u  worst %3u (at %lld, "
                           DHMS_FMT " ago) ", "service",
                           cur, worst, (s64)worstt, DHMS_VARS(&ts));

                lprocfs_at_hist_helper(m, &svcpt->scp_at_estimate);
        }

        return 0;
}

LPROC_SEQ_FOPS_RO(ptlrpc_lprocfs_timeouts);

static ssize_t high_priority_ratio_show(struct kobject *kobj,
                                        struct attribute *attr,
                                        char *buf)
{
        struct ptlrpc_service *svc = container_of(kobj, struct ptlrpc_service,
                                                  srv_kobj);
        return sprintf(buf, "%d\n", svc->srv_hpreq_ratio);
}

static ssize_t high_priority_ratio_store(struct kobject *kobj,
                                         struct attribute *attr,
                                         const char *buffer,
                                         size_t count)
{
        struct ptlrpc_service *svc = container_of(kobj, struct ptlrpc_service,
                                                  srv_kobj);
        int rc;
        int val;

        rc = kstrtoint(buffer, 10, &val);
        if (rc < 0)
                return rc;

        if (val < 0)
                return -ERANGE;

        spin_lock(&svc->srv_lock);
        svc->srv_hpreq_ratio = val;
        spin_unlock(&svc->srv_lock);

        return count;
}
LUSTRE_RW_ATTR(high_priority_ratio);

static struct attribute *ptlrpc_svc_attrs[] = {
        &lustre_attr_threads_min.attr,
        &lustre_attr_threads_started.attr,
        &lustre_attr_threads_max.attr,
        &lustre_attr_high_priority_ratio.attr,
        NULL,
};

static void ptlrpc_sysfs_svc_release(struct kobject *kobj)
{
        struct ptlrpc_service *svc = container_of(kobj, struct ptlrpc_service,
                                                  srv_kobj);

        complete(&svc->srv_kobj_unregister);
}

static struct kobj_type ptlrpc_svc_ktype = {
        .default_attrs  = ptlrpc_svc_attrs,
        .sysfs_ops      = &lustre_sysfs_ops,
        .release        = ptlrpc_sysfs_svc_release,
};

void ptlrpc_sysfs_unregister_service(struct ptlrpc_service *svc)
{
        /* Let's see if we had a chance at initialization first */
        if (svc->srv_kobj.kset) {
                kobject_put(&svc->srv_kobj);
                wait_for_completion(&svc->srv_kobj_unregister);
        }
}

int ptlrpc_sysfs_register_service(struct kset *parent,
                                  struct ptlrpc_service *svc)
{
        int rc;

        svc->srv_kobj.kset = parent;
        init_completion(&svc->srv_kobj_unregister);
        rc = kobject_init_and_add(&svc->srv_kobj, &ptlrpc_svc_ktype, NULL,
                                  "%s", svc->srv_name);

        return rc;
}

void ptlrpc_ldebugfs_register_service(struct dentry *entry,
                                      struct ptlrpc_service *svc)
{
        struct lprocfs_vars lproc_vars[] = {
                {.name       = "req_buffer_history_len",
                 .fops       = &ptlrpc_lprocfs_req_history_len_fops,
                 .data       = svc},
                {.name       = "req_buffer_history_max",
                 .fops       = &ptlrpc_lprocfs_req_history_max_fops,
                 .data       = svc},
                {.name       = "timeouts",
                 .fops       = &ptlrpc_lprocfs_timeouts_fops,
                 .data       = svc},
                {.name       = "nrs_policies",
                 .fops       = &ptlrpc_lprocfs_nrs_fops,
                 .data       = svc},
                {NULL}
        };
        static const struct file_operations req_history_fops = {
                .owner       = THIS_MODULE,
                .open   = ptlrpc_lprocfs_svc_req_history_open,
                .read   = seq_read,
                .llseek      = seq_lseek,
                .release     = lprocfs_seq_release,
        };

        int rc;

        ptlrpc_ldebugfs_register(entry, svc->srv_name,
                                 "stats", &svc->srv_debugfs_entry,
                                 &svc->srv_stats);

        if (IS_ERR_OR_NULL(svc->srv_debugfs_entry))
                return;

        ldebugfs_add_vars(svc->srv_debugfs_entry, lproc_vars, NULL);

        rc = ldebugfs_seq_create(svc->srv_debugfs_entry, "req_history",
                                 0400, &req_history_fops, svc);
        if (rc)
                CWARN("Error adding the req_history file\n");
}

void ptlrpc_lprocfs_register_obd(struct obd_device *obddev)
{
        ptlrpc_ldebugfs_register(obddev->obd_debugfs_entry, NULL, "stats",
                                 &obddev->obd_svc_debugfs_entry,
                                 &obddev->obd_svc_stats);
}
EXPORT_SYMBOL(ptlrpc_lprocfs_register_obd);

void ptlrpc_lprocfs_rpc_sent(struct ptlrpc_request *req, long amount)
{
        struct lprocfs_stats *svc_stats;
        __u32 op = lustre_msg_get_opc(req->rq_reqmsg);
        int opc = opcode_offset(op);

        svc_stats = req->rq_import->imp_obd->obd_svc_stats;
        if (!svc_stats || opc <= 0)
                return;
        LASSERT(opc < LUSTRE_MAX_OPCODES);
        if (!(op == LDLM_ENQUEUE || op == MDS_REINT))
                lprocfs_counter_add(svc_stats, opc + EXTRA_MAX_OPCODES, amount);
}

void ptlrpc_lprocfs_brw(struct ptlrpc_request *req, int bytes)
{
        struct lprocfs_stats *svc_stats;
        int idx;

        if (!req->rq_import)
                return;
        svc_stats = req->rq_import->imp_obd->obd_svc_stats;
        if (!svc_stats)
                return;
        idx = lustre_msg_get_opc(req->rq_reqmsg);
        switch (idx) {
        case OST_READ:
                idx = BRW_READ_BYTES + PTLRPC_LAST_CNTR;
                break;
        case OST_WRITE:
                idx = BRW_WRITE_BYTES + PTLRPC_LAST_CNTR;
                break;
        default:
                LASSERTF(0, "unsupported opcode %u\n", idx);
                break;
        }

        lprocfs_counter_add(svc_stats, idx, bytes);
}
EXPORT_SYMBOL(ptlrpc_lprocfs_brw);

void ptlrpc_lprocfs_unregister_service(struct ptlrpc_service *svc)
{
        if (!IS_ERR_OR_NULL(svc->srv_debugfs_entry))
                ldebugfs_remove(&svc->srv_debugfs_entry);

        if (svc->srv_stats)
                lprocfs_free_stats(&svc->srv_stats);
}

void ptlrpc_lprocfs_unregister_obd(struct obd_device *obd)
{
        if (!IS_ERR_OR_NULL(obd->obd_svc_debugfs_entry))
                ldebugfs_remove(&obd->obd_svc_debugfs_entry);

        if (obd->obd_svc_stats)
                lprocfs_free_stats(&obd->obd_svc_stats);
}
EXPORT_SYMBOL(ptlrpc_lprocfs_unregister_obd);

#undef BUFLEN

int lprocfs_wr_ping(struct file *file, const char __user *buffer,
                    size_t count, loff_t *off)
{
        struct obd_device *obd = ((struct seq_file *)file->private_data)->private;
        struct ptlrpc_request *req;
        int rc;

        rc = lprocfs_climp_check(obd);
        if (rc)
                return rc;

        req = ptlrpc_prep_ping(obd->u.cli.cl_import);
        up_read(&obd->u.cli.cl_sem);
        if (!req)
                return -ENOMEM;

        req->rq_send_state = LUSTRE_IMP_FULL;

        rc = ptlrpc_queue_wait(req);

        ptlrpc_req_finished(req);
        if (rc >= 0)
                return count;
        return rc;
}
EXPORT_SYMBOL(lprocfs_wr_ping);

/* Write the connection UUID to this file to attempt to connect to that node.
 * The connection UUID is a node's primary NID. For example,
 * "echo connection=192.168.0.1@tcp0::instance > .../import".
 */
int lprocfs_wr_import(struct file *file, const char __user *buffer,
                      size_t count, loff_t *off)
{
        struct obd_device *obd = ((struct seq_file *)file->private_data)->private;
        struct obd_import *imp = obd->u.cli.cl_import;
        char *kbuf = NULL;
        char *uuid;
        char *ptr;
        int do_reconn = 1;
        const char prefix[] = "connection=";
        const int prefix_len = sizeof(prefix) - 1;

        if (count > PAGE_SIZE - 1 || count <= prefix_len)
                return -EINVAL;

        kbuf = kzalloc(count + 1, GFP_NOFS);
        if (!kbuf)
                return -ENOMEM;

        if (copy_from_user(kbuf, buffer, count)) {
                count = -EFAULT;
                goto out;
        }

        kbuf[count] = 0;

        /* only support connection=uuid::instance now */
        if (strncmp(prefix, kbuf, prefix_len) != 0) {
                count = -EINVAL;
                goto out;
        }

        uuid = kbuf + prefix_len;
        ptr = strstr(uuid, "::");
        if (ptr) {
                __u32 inst;
                char *endptr;

                *ptr = 0;
                do_reconn = 0;
                ptr += strlen("::");
                inst = simple_strtoul(ptr, &endptr, 10);
                if (*endptr) {
                        CERROR("config: wrong instance # %s\n", ptr);
                } else if (inst != imp->imp_connect_data.ocd_instance) {
                        CDEBUG(D_INFO, "IR: %s is connecting to an obsoleted target(%u/%u), reconnecting...\n",
                               imp->imp_obd->obd_name,
                               imp->imp_connect_data.ocd_instance, inst);
                        do_reconn = 1;
                } else {
                        CDEBUG(D_INFO, "IR: %s has already been connecting to new target(%u)\n",
                               imp->imp_obd->obd_name, inst);
                }
        }

        if (do_reconn)
                ptlrpc_recover_import(imp, uuid, 1);

out:
        kfree(kbuf);
        return count;
}
EXPORT_SYMBOL(lprocfs_wr_import);

int lprocfs_rd_pinger_recov(struct seq_file *m, void *n)
{
        struct obd_device *obd = m->private;
        struct obd_import *imp = obd->u.cli.cl_import;
        int rc;

        rc = lprocfs_climp_check(obd);
        if (rc)
                return rc;

        seq_printf(m, "%d\n", !imp->imp_no_pinger_recover);
        up_read(&obd->u.cli.cl_sem);

        return 0;
}
EXPORT_SYMBOL(lprocfs_rd_pinger_recov);

int lprocfs_wr_pinger_recov(struct file *file, const char __user *buffer,
                            size_t count, loff_t *off)
{
        struct obd_device *obd = ((struct seq_file *)file->private_data)->private;
        struct client_obd *cli = &obd->u.cli;
        struct obd_import *imp = cli->cl_import;
        int rc, val;

        rc = lprocfs_write_helper(buffer, count, &val);
        if (rc < 0)
                return rc;

        if (val != 0 && val != 1)
                return -ERANGE;

        rc = lprocfs_climp_check(obd);
        if (rc)
                return rc;

        spin_lock(&imp->imp_lock);
        imp->imp_no_pinger_recover = !val;
        spin_unlock(&imp->imp_lock);
        up_read(&obd->u.cli.cl_sem);

        return count;
}
EXPORT_SYMBOL(lprocfs_wr_pinger_recov);