/*
 * 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) 2012, 2017, Intel Corporation.
 */
/*
 * This file is part of Lustre, http://www.lustre.org/
 * Lustre is a trademark of Sun Microsystems, Inc.
 */
#define DEBUG_SUBSYSTEM S_LLITE

#include <linux/version.h>
#include <linux/user_namespace.h>
#ifdef HAVE_UIDGID_HEADER
# include <linux/uidgid.h>
#endif
#include <uapi/linux/lustre/lustre_param.h>
#include <lprocfs_status.h>
#include <obd_support.h>

#include "llite_internal.h"
#include "vvp_internal.h"

static struct kobject *llite_kobj;
static struct dentry *llite_root;

int llite_tunables_register(void)
{
	int rc = 0;

	llite_kobj = class_setup_tunables("llite");
	if (IS_ERR(llite_kobj))
		return PTR_ERR(llite_kobj);

	llite_root = debugfs_create_dir("llite", debugfs_lustre_root);
	if (IS_ERR_OR_NULL(llite_root)) {
		rc = llite_root ? PTR_ERR(llite_root) : -ENOMEM;
		llite_root = NULL;
		kobject_put(llite_kobj);
		llite_kobj = NULL;
	}

	return rc;
}

void llite_tunables_unregister(void)
{
	if (llite_kobj) {
		kobject_put(llite_kobj);
		llite_kobj = NULL;
	}

	if (!IS_ERR_OR_NULL(llite_root)) {
		debugfs_remove(llite_root);
		llite_root = NULL;
	}
}

/* <debugfs>/lustre/llite mount point registration */
static const struct file_operations ll_rw_extents_stats_fops;
static const struct file_operations ll_rw_extents_stats_pp_fops;
static const struct file_operations ll_rw_offset_stats_fops;

/**
 * ll_stats_pid_write() - Determine if stats collection should be enabled
 * @buf: Buffer containing the data written
 * @len: Number of bytes in the buffer
 *
 * Several proc files begin collecting stats when a value is written, and stop
 * collecting when either '0' or 'disable' is written. This function checks the
 * written value to see if collection should be enabled or disabled.
 *
 * Return: If '0' or 'disable' is provided, 0 is returned. If the text
 * equivalent of a number is written, that number is returned. Otherwise,
 * 1 is returned. Non-zero return values indicate collection should be enabled.
 */
static s64 ll_stats_pid_write(const char __user *buf, size_t len)
{
	unsigned long long value = 1;
	char kernbuf[16];
	int rc;

	rc = kstrtoull_from_user(buf, len, 0, &value);
	if (rc < 0 && len < sizeof(kernbuf)) {
		if (copy_from_user(kernbuf, buf, len))
			return -EFAULT;
		kernbuf[len] = 0;

		if (kernbuf[len - 1] == '\n')
			kernbuf[len - 1] = 0;

		if (strncasecmp(kernbuf, "disable", 7) == 0)
			value = 0;
	}

	return value;
}

static ssize_t blocksize_show(struct kobject *kobj, struct attribute *attr,
			      char *buf)
{
	struct ll_sb_info *sbi = container_of(kobj, struct ll_sb_info,
					      ll_kset.kobj);
	struct obd_statfs osfs;
	int rc;

	rc = ll_statfs_internal(sbi, &osfs, OBD_STATFS_NODELAY);
	if (rc)
		return rc;

	return sprintf(buf, "%u\n", osfs.os_bsize);
}
LUSTRE_RO_ATTR(blocksize);

static ssize_t stat_blocksize_show(struct kobject *kobj, struct attribute *attr,
				   char *buf)
{
	struct ll_sb_info *sbi = container_of(kobj, struct ll_sb_info,
					      ll_kset.kobj);

	return sprintf(buf, "%u\n", sbi->ll_stat_blksize);
}

static ssize_t stat_blocksize_store(struct kobject *kobj,
				    struct attribute *attr,
				    const char *buffer,
				    size_t count)
{
	struct ll_sb_info *sbi = container_of(kobj, struct ll_sb_info,
					      ll_kset.kobj);
	unsigned int val;
	int rc;

	rc = kstrtouint(buffer, 10, &val);
	if (rc)
		return rc;

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

	sbi->ll_stat_blksize = val;

	return count;
}
LUSTRE_RW_ATTR(stat_blocksize);

static ssize_t kbytestotal_show(struct kobject *kobj, struct attribute *attr,
				char *buf)
{
	struct ll_sb_info *sbi = container_of(kobj, struct ll_sb_info,
					      ll_kset.kobj);
	struct obd_statfs osfs;
	u32 blk_size;
	u64 result;
	int rc;

	rc = ll_statfs_internal(sbi, &osfs, OBD_STATFS_NODELAY);
	if (rc)
		return rc;

	blk_size = osfs.os_bsize >> 10;
	result = osfs.os_blocks;

	while (blk_size >>= 1)
		result <<= 1;

	return sprintf(buf, "%llu\n", result);
}
LUSTRE_RO_ATTR(kbytestotal);

static ssize_t kbytesfree_show(struct kobject *kobj, struct attribute *attr,
			       char *buf)
{
	struct ll_sb_info *sbi = container_of(kobj, struct ll_sb_info,
					      ll_kset.kobj);
	struct obd_statfs osfs;
	u32 blk_size;
	u64 result;
	int rc;

	rc = ll_statfs_internal(sbi, &osfs, OBD_STATFS_NODELAY);
	if (rc)
		return rc;

	blk_size = osfs.os_bsize >> 10;
	result = osfs.os_bfree;

	while (blk_size >>= 1)
		result <<= 1;

	return sprintf(buf, "%llu\n", result);
}
LUSTRE_RO_ATTR(kbytesfree);

static ssize_t kbytesavail_show(struct kobject *kobj, struct attribute *attr,
				char *buf)
{
	struct ll_sb_info *sbi = container_of(kobj, struct ll_sb_info,
					      ll_kset.kobj);
	struct obd_statfs osfs;
	u32 blk_size;
	u64 result;
	int rc;

	rc = ll_statfs_internal(sbi, &osfs, OBD_STATFS_NODELAY);
	if (rc)
		return rc;

	blk_size = osfs.os_bsize >> 10;
	result = osfs.os_bavail;

	while (blk_size >>= 1)
		result <<= 1;

	return sprintf(buf, "%llu\n", result);
}
LUSTRE_RO_ATTR(kbytesavail);

static ssize_t filestotal_show(struct kobject *kobj, struct attribute *attr,
			       char *buf)
{
	struct ll_sb_info *sbi = container_of(kobj, struct ll_sb_info,
					      ll_kset.kobj);
	struct obd_statfs osfs;
	int rc;

	rc = ll_statfs_internal(sbi, &osfs, OBD_STATFS_NODELAY);
	if (rc)
		return rc;

	return sprintf(buf, "%llu\n", osfs.os_files);
}
LUSTRE_RO_ATTR(filestotal);

static ssize_t filesfree_show(struct kobject *kobj, struct attribute *attr,
			      char *buf)
{
	struct ll_sb_info *sbi = container_of(kobj, struct ll_sb_info,
					      ll_kset.kobj);
	struct obd_statfs osfs;
	int rc;

	rc = ll_statfs_internal(sbi, &osfs, OBD_STATFS_NODELAY);
	if (rc)
		return rc;

	return sprintf(buf, "%llu\n", osfs.os_ffree);
}
LUSTRE_RO_ATTR(filesfree);

static ssize_t client_type_show(struct kobject *kobj, struct attribute *attr,
				char *buf)
{
	return sprintf(buf, "local client\n");
}
LUSTRE_RO_ATTR(client_type);

static ssize_t fstype_show(struct kobject *kobj, struct attribute *attr,
			   char *buf)
{
	return sprintf(buf, "lustre\n");
}
LUSTRE_RO_ATTR(fstype);

static ssize_t uuid_show(struct kobject *kobj, struct attribute *attr,
			 char *buf)
{
	struct ll_sb_info *sbi = container_of(kobj, struct ll_sb_info,
					      ll_kset.kobj);

	return sprintf(buf, "%s\n", sbi->ll_sb_uuid.uuid);
}
LUSTRE_RO_ATTR(uuid);

static int ll_site_stats_seq_show(struct seq_file *m, void *v)
{
	struct super_block *sb = m->private;

	/*
	 * See description of statistical counters in struct cl_site, and
	 * struct lu_site.
	 */
	return cl_site_stats_print(lu2cl_site(ll_s2sbi(sb)->ll_site), m);
}

LDEBUGFS_SEQ_FOPS_RO(ll_site_stats);

static int ll_max_readahead_mb_seq_show(struct seq_file *m, void *v)
{
	struct super_block *sb = m->private;
	struct ll_sb_info *sbi = ll_s2sbi(sb);
	long pages_number;
	int mult;

	spin_lock(&sbi->ll_lock);
	pages_number = sbi->ll_ra_info.ra_max_pages;
	spin_unlock(&sbi->ll_lock);

	mult = 1 << (20 - PAGE_SHIFT);
	return lprocfs_seq_read_frac_helper(m, pages_number, mult);
}

static ssize_t
ll_max_readahead_mb_seq_write(struct file *file, const char __user *buffer,
			      size_t count, loff_t *off)
{
	struct seq_file *m = file->private_data;
	struct super_block *sb = m->private;
	struct ll_sb_info *sbi = ll_s2sbi(sb);
	__s64 pages_number;
	int rc;

	rc = lprocfs_str_with_units_to_s64(buffer, count, &pages_number, 'M');
	if (rc)
		return rc;

	pages_number >>= PAGE_SHIFT;

	if (pages_number < 0 || pages_number > totalram_pages / 2) {
		/* 1/2 of RAM */
		CERROR("%s: can't set max_readahead_mb=%lu > %luMB\n",
		       ll_get_fsname(sb, NULL, 0),
		       (unsigned long)pages_number >> (20 - PAGE_SHIFT),
		       totalram_pages >> (20 - PAGE_SHIFT + 1));
		return -ERANGE;
	}

	spin_lock(&sbi->ll_lock);
	sbi->ll_ra_info.ra_max_pages = pages_number;
	spin_unlock(&sbi->ll_lock);

	return count;
}

LDEBUGFS_SEQ_FOPS(ll_max_readahead_mb);

static int ll_max_readahead_per_file_mb_seq_show(struct seq_file *m, void *v)
{
	struct super_block *sb = m->private;
	struct ll_sb_info *sbi = ll_s2sbi(sb);
	long pages_number;
	int mult;

	spin_lock(&sbi->ll_lock);
	pages_number = sbi->ll_ra_info.ra_max_pages_per_file;
	spin_unlock(&sbi->ll_lock);

	mult = 1 << (20 - PAGE_SHIFT);
	return lprocfs_seq_read_frac_helper(m, pages_number, mult);
}

static ssize_t
ll_max_readahead_per_file_mb_seq_write(struct file *file,
				       const char __user *buffer,
				       size_t count, loff_t *off)
{
	struct seq_file *m = file->private_data;
	struct super_block *sb = m->private;
	struct ll_sb_info *sbi = ll_s2sbi(sb);
	int rc;
	__s64 pages_number;

	rc = lprocfs_str_with_units_to_s64(buffer, count, &pages_number, 'M');
	if (rc)
		return rc;

	pages_number >>= PAGE_SHIFT;

	if (pages_number < 0 || pages_number > sbi->ll_ra_info.ra_max_pages) {
		CERROR("%s: can't set max_readahead_per_file_mb=%lu > "
		       "max_read_ahead_mb=%lu\n", ll_get_fsname(sb, NULL, 0),
		       (unsigned long)pages_number >> (20 - PAGE_SHIFT),
		       sbi->ll_ra_info.ra_max_pages >> (20 - PAGE_SHIFT));
		return -ERANGE;
	}

	spin_lock(&sbi->ll_lock);
	sbi->ll_ra_info.ra_max_pages_per_file = pages_number;
	spin_unlock(&sbi->ll_lock);

	return count;
}

LDEBUGFS_SEQ_FOPS(ll_max_readahead_per_file_mb);

static int ll_max_read_ahead_whole_mb_seq_show(struct seq_file *m, void *v)
{
	struct super_block *sb = m->private;
	struct ll_sb_info *sbi = ll_s2sbi(sb);
	long pages_number;
	int mult;

	spin_lock(&sbi->ll_lock);
	pages_number = sbi->ll_ra_info.ra_max_read_ahead_whole_pages;
	spin_unlock(&sbi->ll_lock);

	mult = 1 << (20 - PAGE_SHIFT);
	return lprocfs_seq_read_frac_helper(m, pages_number, mult);
}

static ssize_t
ll_max_read_ahead_whole_mb_seq_write(struct file *file,
				     const char __user *buffer,
				     size_t count, loff_t *off)
{
	struct seq_file *m = file->private_data;
	struct super_block *sb = m->private;
	struct ll_sb_info *sbi = ll_s2sbi(sb);
	int rc;
	__s64 pages_number;

	rc = lprocfs_str_with_units_to_s64(buffer, count, &pages_number, 'M');
	if (rc)
		return rc;

	pages_number >>= PAGE_SHIFT;

	/* Cap this at the current max readahead window size, the readahead
	 * algorithm does this anyway so it's pointless to set it larger. */
	if (pages_number < 0 ||
	    pages_number > sbi->ll_ra_info.ra_max_pages_per_file) {
		int pages_shift = 20 - PAGE_SHIFT;
		CERROR("%s: can't set max_read_ahead_whole_mb=%lu > "
		       "max_read_ahead_per_file_mb=%lu\n",
		       ll_get_fsname(sb, NULL, 0),
		       (unsigned long)pages_number >> pages_shift,
		       sbi->ll_ra_info.ra_max_pages_per_file >> pages_shift);
		return -ERANGE;
	}

	spin_lock(&sbi->ll_lock);
	sbi->ll_ra_info.ra_max_read_ahead_whole_pages = pages_number;
	spin_unlock(&sbi->ll_lock);

	return count;
}

LDEBUGFS_SEQ_FOPS(ll_max_read_ahead_whole_mb);

static int ll_max_cached_mb_seq_show(struct seq_file *m, void *v)
{
	struct super_block     *sb    = m->private;
	struct ll_sb_info      *sbi   = ll_s2sbi(sb);
	struct cl_client_cache *cache = sbi->ll_cache;
	int shift = 20 - PAGE_SHIFT;
	long max_cached_mb;
	long unused_mb;

	max_cached_mb = cache->ccc_lru_max >> shift;
	unused_mb = atomic_long_read(&cache->ccc_lru_left) >> shift;
	seq_printf(m, "users: %d\n"
		      "max_cached_mb: %ld\n"
		      "used_mb: %ld\n"
		      "unused_mb: %ld\n"
		      "reclaim_count: %u\n",
		   atomic_read(&cache->ccc_users),
		   max_cached_mb,
		   max_cached_mb - unused_mb,
		   unused_mb,
		   cache->ccc_lru_shrinkers);
	return 0;
}

static ssize_t ll_max_cached_mb_seq_write(struct file *file,
					  const char __user *buffer,
					  size_t count, loff_t *off)
{
	struct seq_file *m = file->private_data;
	struct super_block *sb = m->private;
	struct ll_sb_info *sbi = ll_s2sbi(sb);
	struct cl_client_cache *cache = sbi->ll_cache;
	struct lu_env *env;
	long diff = 0;
	long nrpages = 0;
	__u16 refcheck;
	__s64 pages_number;
	int rc;
	char kernbuf[128];

	ENTRY;
	if (count >= sizeof(kernbuf))
		RETURN(-EINVAL);

	if (copy_from_user(kernbuf, buffer, count))
		RETURN(-EFAULT);
	kernbuf[count] = 0;

	buffer += lprocfs_find_named_value(kernbuf, "max_cached_mb:", &count) -
		  kernbuf;
	rc = lprocfs_str_with_units_to_s64(buffer, count, &pages_number, 'M');
	if (rc)
		RETURN(rc);

	pages_number >>= PAGE_SHIFT;

	if (pages_number < 0 || pages_number > totalram_pages) {
		CERROR("%s: can't set max cache more than %lu MB\n",
		       ll_get_fsname(sb, NULL, 0),
		       totalram_pages >> (20 - PAGE_SHIFT));
		RETURN(-ERANGE);
	}
	/* Allow enough cache so clients can make well-formed RPCs */
	pages_number = max_t(long, pages_number, PTLRPC_MAX_BRW_PAGES);

	spin_lock(&sbi->ll_lock);
	diff = pages_number - cache->ccc_lru_max;
	spin_unlock(&sbi->ll_lock);

	/* easy - add more LRU slots. */
	if (diff >= 0) {
		atomic_long_add(diff, &cache->ccc_lru_left);
		GOTO(out, rc = 0);
	}

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

	diff = -diff;
	while (diff > 0) {
		long tmp;

		/* reduce LRU budget from free slots. */
		do {
			long ov, nv;

			ov = atomic_long_read(&cache->ccc_lru_left);
			if (ov == 0)
				break;

			nv = ov > diff ? ov - diff : 0;
			rc = atomic_long_cmpxchg(&cache->ccc_lru_left, ov, nv);
			if (likely(ov == rc)) {
				diff -= ov - nv;
				nrpages += ov - nv;
				break;
			}
		} while (1);

		if (diff <= 0)
			break;

		if (sbi->ll_dt_exp == NULL) { /* being initialized */
			rc = -ENODEV;
			break;
		}

		/* difficult - have to ask OSCs to drop LRU slots. */
		tmp = diff << 1;
		rc = obd_set_info_async(env, sbi->ll_dt_exp,
				sizeof(KEY_CACHE_LRU_SHRINK),
				KEY_CACHE_LRU_SHRINK,
				sizeof(tmp), &tmp, NULL);
		if (rc < 0)
			break;
	}
	cl_env_put(env, &refcheck);

out:
	if (rc >= 0) {
		spin_lock(&sbi->ll_lock);
		cache->ccc_lru_max = pages_number;
		spin_unlock(&sbi->ll_lock);
		rc = count;
	} else {
		atomic_long_add(nrpages, &cache->ccc_lru_left);
	}
	return rc;
}

LDEBUGFS_SEQ_FOPS(ll_max_cached_mb);

static ssize_t checksums_show(struct kobject *kobj, struct attribute *attr,
			      char *buf)
{
	struct ll_sb_info *sbi = container_of(kobj, struct ll_sb_info,
					      ll_kset.kobj);

	return sprintf(buf, "%u\n", (sbi->ll_flags & LL_SBI_CHECKSUM) ? 1 : 0);
}

static ssize_t checksums_store(struct kobject *kobj, struct attribute *attr,
			       const char *buffer, size_t count)
{
	struct ll_sb_info *sbi = container_of(kobj, struct ll_sb_info,
					      ll_kset.kobj);
	bool val;
	int tmp;
	int rc;

	if (!sbi->ll_dt_exp)
		/* Not set up yet */
		return -EAGAIN;

	rc = kstrtobool(buffer, &val);
	if (rc)
		return rc;
	if (val)
		sbi->ll_flags |= LL_SBI_CHECKSUM;
	else
		sbi->ll_flags &= ~LL_SBI_CHECKSUM;
	tmp = val;

	rc = obd_set_info_async(NULL, sbi->ll_dt_exp, sizeof(KEY_CHECKSUM),
				KEY_CHECKSUM, sizeof(tmp), &tmp, NULL);
	if (rc)
		CWARN("Failed to set OSC checksum flags: %d\n", rc);

	return count;
}
LUSTRE_RW_ATTR(checksums);

LUSTRE_ATTR(checksum_pages, 0644, checksums_show, checksums_store);

static ssize_t ll_rd_track_id(struct kobject *kobj, char *buf,
			      enum stats_track_type type)
{
	struct ll_sb_info *sbi = container_of(kobj, struct ll_sb_info,
					      ll_kset.kobj);

	if (sbi->ll_stats_track_type == type)
		return sprintf(buf, "%d\n", sbi->ll_stats_track_id);
	else if (sbi->ll_stats_track_type == STATS_TRACK_ALL)
		return sprintf(buf, "0 (all)\n");

	return sprintf(buf, "untracked\n");
}

static ssize_t ll_wr_track_id(struct kobject *kobj, const char *buffer,
			      size_t count, enum stats_track_type type)
{
	struct ll_sb_info *sbi = container_of(kobj, struct ll_sb_info,
					      ll_kset.kobj);
	unsigned long pid;
	int rc;

	rc = kstrtoul(buffer, 10, &pid);
	if (rc)
		return rc;

	sbi->ll_stats_track_id = pid;
	if (pid == 0)
		sbi->ll_stats_track_type = STATS_TRACK_ALL;
	else
		sbi->ll_stats_track_type = type;
	lprocfs_clear_stats(sbi->ll_stats);
	return count;
}

static ssize_t stats_track_pid_show(struct kobject *kobj,
				    struct attribute *attr,
				    char *buf)
{
	return ll_rd_track_id(kobj, buf, STATS_TRACK_PID);
}

static ssize_t stats_track_pid_store(struct kobject *kobj,
				     struct attribute *attr,
				     const char *buffer,
				     size_t count)
{
	return ll_wr_track_id(kobj, buffer, count, STATS_TRACK_PID);
}
LUSTRE_RW_ATTR(stats_track_pid);

static ssize_t stats_track_ppid_show(struct kobject *kobj,
				     struct attribute *attr,
				     char *buf)
{
	return ll_rd_track_id(kobj, buf, STATS_TRACK_PPID);
}

static ssize_t stats_track_ppid_store(struct kobject *kobj,
				      struct attribute *attr,
				      const char *buffer,
				      size_t count)
{
	return ll_wr_track_id(kobj, buffer, count, STATS_TRACK_PPID);
}
LUSTRE_RW_ATTR(stats_track_ppid);

static ssize_t stats_track_gid_show(struct kobject *kobj,
				    struct attribute *attr,
				    char *buf)
{
	return ll_rd_track_id(kobj, buf, STATS_TRACK_GID);
}

static ssize_t stats_track_gid_store(struct kobject *kobj,
				     struct attribute *attr,
				     const char *buffer,
				     size_t count)
{
	return ll_wr_track_id(kobj, buffer, count, STATS_TRACK_GID);
}
LUSTRE_RW_ATTR(stats_track_gid);

static ssize_t statahead_running_max_show(struct kobject *kobj,
					  struct attribute *attr,
					  char *buf)
{
	struct ll_sb_info *sbi = container_of(kobj, struct ll_sb_info,
					      ll_kset.kobj);

	return snprintf(buf, 16, "%u\n", sbi->ll_sa_running_max);
}

static ssize_t statahead_running_max_store(struct kobject *kobj,
					   struct attribute *attr,
					   const char *buffer,
					   size_t count)
{
	struct ll_sb_info *sbi = container_of(kobj, struct ll_sb_info,
					      ll_kset.kobj);
	unsigned long val;
	int rc;

	rc = kstrtoul(buffer, 0, &val);
	if (rc)
		return rc;

	if (val <= LL_SA_RUNNING_MAX) {
		sbi->ll_sa_running_max = val;
		return count;
	}

	CERROR("Bad statahead_running_max value %lu. Valid values "
	       "are in the range [0, %d]\n", val, LL_SA_RUNNING_MAX);

	return -ERANGE;
}
LUSTRE_RW_ATTR(statahead_running_max);

static ssize_t statahead_max_show(struct kobject *kobj,
				  struct attribute *attr,
				  char *buf)
{
	struct ll_sb_info *sbi = container_of(kobj, struct ll_sb_info,
					      ll_kset.kobj);

	return sprintf(buf, "%u\n", sbi->ll_sa_max);
}

static ssize_t statahead_max_store(struct kobject *kobj,
				   struct attribute *attr,
				   const char *buffer,
				   size_t count)
{
	struct ll_sb_info *sbi = container_of(kobj, struct ll_sb_info,
					      ll_kset.kobj);
	unsigned long val;
	int rc;

	rc = kstrtoul(buffer, 0, &val);
	if (rc)
		return rc;

	if (val <= LL_SA_RPC_MAX)
		sbi->ll_sa_max = val;
	else
		CERROR("Bad statahead_max value %lu. Valid values are in the range [0, %d]\n",
		       val, LL_SA_RPC_MAX);

	return count;
}
LUSTRE_RW_ATTR(statahead_max);

static ssize_t statahead_agl_show(struct kobject *kobj,
				  struct attribute *attr,
				  char *buf)
{
	struct ll_sb_info *sbi = container_of(kobj, struct ll_sb_info,
					      ll_kset.kobj);

	return sprintf(buf, "%u\n", sbi->ll_flags & LL_SBI_AGL_ENABLED ? 1 : 0);
}

static ssize_t statahead_agl_store(struct kobject *kobj,
				   struct attribute *attr,
				   const char *buffer,
				   size_t count)
{
	struct ll_sb_info *sbi = container_of(kobj, struct ll_sb_info,
					      ll_kset.kobj);
	bool val;
	int rc;

	rc = kstrtobool(buffer, &val);
	if (rc)
		return rc;

	if (val)
		sbi->ll_flags |= LL_SBI_AGL_ENABLED;
	else
		sbi->ll_flags &= ~LL_SBI_AGL_ENABLED;

	return count;
}
LUSTRE_RW_ATTR(statahead_agl);

static int ll_statahead_stats_seq_show(struct seq_file *m, void *v)
{
	struct super_block *sb = m->private;
	struct ll_sb_info *sbi = ll_s2sbi(sb);

	seq_printf(m, "statahead total: %u\n"
		      "statahead wrong: %u\n"
		      "agl total: %u\n",
		   atomic_read(&sbi->ll_sa_total),
		   atomic_read(&sbi->ll_sa_wrong),
		   atomic_read(&sbi->ll_agl_total));
	return 0;
}

LDEBUGFS_SEQ_FOPS_RO(ll_statahead_stats);

static ssize_t lazystatfs_show(struct kobject *kobj,
			       struct attribute *attr,
			       char *buf)
{
	struct ll_sb_info *sbi = container_of(kobj, struct ll_sb_info,
					      ll_kset.kobj);

	return sprintf(buf, "%u\n", (sbi->ll_flags & LL_SBI_LAZYSTATFS) ? 1 : 0);
}

static ssize_t lazystatfs_store(struct kobject *kobj,
				struct attribute *attr,
				const char *buffer,
				size_t count)
{
	struct ll_sb_info *sbi = container_of(kobj, struct ll_sb_info,
					      ll_kset.kobj);
	bool val;
	int rc;

	rc = kstrtobool(buffer, &val);
	if (rc)
		return rc;

	if (val)
		sbi->ll_flags |= LL_SBI_LAZYSTATFS;
	else
		sbi->ll_flags &= ~LL_SBI_LAZYSTATFS;

	return count;
}
LUSTRE_RW_ATTR(lazystatfs);

static ssize_t max_easize_show(struct kobject *kobj,
			       struct attribute *attr,
			       char *buf)
{
	struct ll_sb_info *sbi = container_of(kobj, struct ll_sb_info,
					      ll_kset.kobj);
	unsigned int ealen;
	int rc;

	rc = ll_get_max_mdsize(sbi, &ealen);
	if (rc)
		return rc;

	return sprintf(buf, "%u\n", ealen);
}
LUSTRE_RO_ATTR(max_easize);

/**
 * Get default_easize.
 *
 * \see client_obd::cl_default_mds_easize
 *
 * \param[in] m		seq_file handle
 * \param[in] v		unused for single entry
 *
 * \retval 0		on success
 * \retval negative	negated errno on failure
 */
static ssize_t default_easize_show(struct kobject *kobj,
				   struct attribute *attr,
				   char *buf)
{
	struct ll_sb_info *sbi = container_of(kobj, struct ll_sb_info,
					      ll_kset.kobj);
	unsigned int ealen;
	int rc;

	rc = ll_get_default_mdsize(sbi, &ealen);
	if (rc)
		return rc;

	return sprintf(buf, "%u\n", ealen);
}

/**
 * Set default_easize.
 *
 * Range checking on the passed value is handled by
 * ll_set_default_mdsize().
 *
 * \see client_obd::cl_default_mds_easize
 *
 * \param[in] file	proc file
 * \param[in] buffer	string passed from user space
 * \param[in] count	\a buffer length
 * \param[in] off	unused for single entry
 *
 * \retval positive	\a count on success
 * \retval negative	negated errno on failure
 */
static ssize_t default_easize_store(struct kobject *kobj,
				    struct attribute *attr,
				    const char *buffer,
				    size_t count)
{
	struct ll_sb_info *sbi = container_of(kobj, struct ll_sb_info,
					      ll_kset.kobj);
	unsigned int val;
	int rc;

	if (count == 0)
		return 0;

	rc = kstrtouint(buffer, 10, &val);
	if (rc)
		return rc;

	rc = ll_set_default_mdsize(sbi, val);
	if (rc)
		return rc;

	return count;
}
LUSTRE_RW_ATTR(default_easize);

static int ll_sbi_flags_seq_show(struct seq_file *m, void *v)
{
	const char *str[] = LL_SBI_FLAGS;
	struct super_block *sb = m->private;
	int flags = ll_s2sbi(sb)->ll_flags;
	int i = 0;

	while (flags != 0) {
		if (ARRAY_SIZE(str) <= i) {
			CERROR("%s: Revise array LL_SBI_FLAGS to match sbi "
				"flags please.\n", ll_get_fsname(sb, NULL, 0));
			return -EINVAL;
		}

		if (flags & 0x1)
			seq_printf(m, "%s ", str[i]);
		flags >>= 1;
		++i;
	}
	seq_printf(m, "\b\n");
	return 0;
}

LDEBUGFS_SEQ_FOPS_RO(ll_sbi_flags);

static ssize_t xattr_cache_show(struct kobject *kobj,
				struct attribute *attr,
				char *buf)
{
	struct ll_sb_info *sbi = container_of(kobj, struct ll_sb_info,
					      ll_kset.kobj);

	return sprintf(buf, "%u\n", sbi->ll_xattr_cache_enabled);
}

static ssize_t xattr_cache_store(struct kobject *kobj,
				 struct attribute *attr,
				 const char *buffer,
				 size_t count)
{
	struct ll_sb_info *sbi = container_of(kobj, struct ll_sb_info,
					      ll_kset.kobj);
	bool val;
	int rc;

	rc = kstrtobool(buffer, &val);
	if (rc)
		return rc;

	if (val && !(sbi->ll_flags & LL_SBI_XATTR_CACHE))
		return -ENOTSUPP;

	sbi->ll_xattr_cache_enabled = val;
	sbi->ll_xattr_cache_set = 1;

	return count;
}
LUSTRE_RW_ATTR(xattr_cache);

static ssize_t tiny_write_show(struct kobject *kobj,
			       struct attribute *attr,
			       char *buf)
{
	struct ll_sb_info *sbi = container_of(kobj, struct ll_sb_info,
					      ll_kset.kobj);

	return sprintf(buf, "%u\n", !!(sbi->ll_flags & LL_SBI_TINY_WRITE));
}

static ssize_t tiny_write_store(struct kobject *kobj,
				struct attribute *attr,
				const char *buffer,
				size_t count)
{
	struct ll_sb_info *sbi = container_of(kobj, struct ll_sb_info,
					      ll_kset.kobj);
	bool val;
	int rc;

	rc = kstrtobool(buffer, &val);
	if (rc)
		return rc;

	spin_lock(&sbi->ll_lock);
	if (val)
		sbi->ll_flags |= LL_SBI_TINY_WRITE;
	else
		sbi->ll_flags &= ~LL_SBI_TINY_WRITE;
	spin_unlock(&sbi->ll_lock);

	return count;
}
LUSTRE_RW_ATTR(tiny_write);

static ssize_t fast_read_show(struct kobject *kobj,
			      struct attribute *attr,
			      char *buf)
{
	struct ll_sb_info *sbi = container_of(kobj, struct ll_sb_info,
					      ll_kset.kobj);

	return sprintf(buf, "%u\n", !!(sbi->ll_flags & LL_SBI_FAST_READ));
}

static ssize_t fast_read_store(struct kobject *kobj,
			       struct attribute *attr,
			       const char *buffer,
			       size_t count)
{
	struct ll_sb_info *sbi = container_of(kobj, struct ll_sb_info,
					      ll_kset.kobj);
	bool val;
	int rc;

	rc = kstrtobool(buffer, &val);
	if (rc)
		return rc;

	spin_lock(&sbi->ll_lock);
	if (val)
		sbi->ll_flags |= LL_SBI_FAST_READ;
	else
		sbi->ll_flags &= ~LL_SBI_FAST_READ;
	spin_unlock(&sbi->ll_lock);

	return count;
}
LUSTRE_RW_ATTR(fast_read);

static int ll_unstable_stats_seq_show(struct seq_file *m, void *v)
{
	struct super_block	*sb    = m->private;
	struct ll_sb_info	*sbi   = ll_s2sbi(sb);
	struct cl_client_cache	*cache = sbi->ll_cache;
	long pages;
	int mb;

	pages = atomic_long_read(&cache->ccc_unstable_nr);
	mb    = (pages * PAGE_SIZE) >> 20;

	seq_printf(m, "unstable_check:     %8d\n"
		      "unstable_pages: %12ld\n"
		      "unstable_mb:        %8d\n",
		   cache->ccc_unstable_check, pages, mb);
	return 0;
}

static ssize_t ll_unstable_stats_seq_write(struct file *file,
					   const char __user *buffer,
					   size_t count, loff_t *unused)
{
	struct seq_file *seq = file->private_data;
	struct ll_sb_info *sbi = ll_s2sbi((struct super_block *)seq->private);
	char kernbuf[128];
	bool val;
	int rc;

	if (count == 0)
		return 0;
	if (count >= sizeof(kernbuf))
		return -EINVAL;

	if (copy_from_user(kernbuf, buffer, count))
		return -EFAULT;
	kernbuf[count] = 0;

	buffer += lprocfs_find_named_value(kernbuf, "unstable_check:", &count) -
		  kernbuf;
	rc = kstrtobool_from_user(buffer, count, &val);
	if (rc < 0)
		return rc;

	/* borrow lru lock to set the value */
	spin_lock(&sbi->ll_cache->ccc_lru_lock);
	sbi->ll_cache->ccc_unstable_check = val;
	spin_unlock(&sbi->ll_cache->ccc_lru_lock);

	return count;
}

LDEBUGFS_SEQ_FOPS(ll_unstable_stats);

static int ll_root_squash_seq_show(struct seq_file *m, void *v)
{
	struct super_block *sb = m->private;
	struct ll_sb_info *sbi = ll_s2sbi(sb);
	struct root_squash_info *squash = &sbi->ll_squash;

	seq_printf(m, "%u:%u\n", squash->rsi_uid, squash->rsi_gid);
	return 0;
}

static ssize_t ll_root_squash_seq_write(struct file *file,
					const char __user *buffer,
					size_t count, loff_t *off)
{
	struct seq_file *m = file->private_data;
	struct super_block *sb = m->private;
	struct ll_sb_info *sbi = ll_s2sbi(sb);
	struct root_squash_info *squash = &sbi->ll_squash;

	return lprocfs_wr_root_squash(buffer, count, squash,
				      ll_get_fsname(sb, NULL, 0));
}

LDEBUGFS_SEQ_FOPS(ll_root_squash);

static int ll_nosquash_nids_seq_show(struct seq_file *m, void *v)
{
	struct super_block *sb = m->private;
	struct ll_sb_info *sbi = ll_s2sbi(sb);
	struct root_squash_info *squash = &sbi->ll_squash;
	int len;

	down_read(&squash->rsi_sem);
	if (!list_empty(&squash->rsi_nosquash_nids)) {
		len = cfs_print_nidlist(m->buf + m->count, m->size - m->count,
					&squash->rsi_nosquash_nids);
		m->count += len;
		seq_putc(m, '\n');
	} else {
		seq_puts(m, "NONE\n");
	}
	up_read(&squash->rsi_sem);

	return 0;
}

static ssize_t ll_nosquash_nids_seq_write(struct file *file,
					  const char __user *buffer,
					  size_t count, loff_t *off)
{
	struct seq_file *m = file->private_data;
	struct super_block *sb = m->private;
	struct ll_sb_info *sbi = ll_s2sbi(sb);
	struct root_squash_info *squash = &sbi->ll_squash;
	int rc;

	rc = lprocfs_wr_nosquash_nids(buffer, count, squash,
				      ll_get_fsname(sb, NULL, 0));
	if (rc < 0)
		return rc;

	ll_compute_rootsquash_state(sbi);

	return rc;
}

LDEBUGFS_SEQ_FOPS(ll_nosquash_nids);

struct lprocfs_vars lprocfs_llite_obd_vars[] = {
	{ .name	=	"site",
	  .fops	=	&ll_site_stats_fops			},
	{ .name =	"max_read_ahead_mb",
	  .fops =	&ll_max_readahead_mb_fops		},
	{ .name =	"max_read_ahead_per_file_mb",
	  .fops =	&ll_max_readahead_per_file_mb_fops	},
	{ .name =	"max_read_ahead_whole_mb",
	  .fops =	&ll_max_read_ahead_whole_mb_fops	},
	{ .name	=	"max_cached_mb",
	  .fops	=	&ll_max_cached_mb_fops			},
	{ .name	=	"statahead_stats",
	  .fops	=	&ll_statahead_stats_fops		},
	{ .name	=	"unstable_stats",
	  .fops	=	&ll_unstable_stats_fops			},
	{ .name =	"sbi_flags",
	  .fops =	&ll_sbi_flags_fops			},
	{ .name	=	"root_squash",
	  .fops	=	&ll_root_squash_fops			},
	{ .name	=	"nosquash_nids",
	  .fops	=	&ll_nosquash_nids_fops			},
	{ NULL }
};

#define MAX_STRING_SIZE 128

static struct attribute *llite_attrs[] = {
	&lustre_attr_blocksize.attr,
	&lustre_attr_stat_blocksize.attr,
	&lustre_attr_kbytestotal.attr,
	&lustre_attr_kbytesfree.attr,
	&lustre_attr_kbytesavail.attr,
	&lustre_attr_filestotal.attr,
	&lustre_attr_filesfree.attr,
	&lustre_attr_client_type.attr,
	&lustre_attr_fstype.attr,
	&lustre_attr_uuid.attr,
	&lustre_attr_checksums.attr,
	&lustre_attr_checksum_pages.attr,
	&lustre_attr_stats_track_pid.attr,
	&lustre_attr_stats_track_ppid.attr,
	&lustre_attr_stats_track_gid.attr,
	&lustre_attr_statahead_running_max.attr,
	&lustre_attr_statahead_max.attr,
	&lustre_attr_statahead_agl.attr,
	&lustre_attr_lazystatfs.attr,
	&lustre_attr_max_easize.attr,
	&lustre_attr_default_easize.attr,
	&lustre_attr_xattr_cache.attr,
	&lustre_attr_fast_read.attr,
	&lustre_attr_tiny_write.attr,
	NULL,
};

static void llite_kobj_release(struct kobject *kobj)
{
	struct ll_sb_info *sbi = container_of(kobj, struct ll_sb_info,
					      ll_kset.kobj);
	complete(&sbi->ll_kobj_unregister);
}

static struct kobj_type llite_ktype = {
	.default_attrs  = llite_attrs,
	.sysfs_ops      = &lustre_sysfs_ops,
	.release        = llite_kobj_release,
};

static const struct llite_file_opcode {
        __u32       opcode;
        __u32       type;
        const char *opname;
} llite_opcode_table[LPROC_LL_FILE_OPCODES] = {
        /* file operation */
        { LPROC_LL_DIRTY_HITS,     LPROCFS_TYPE_REGS, "dirty_pages_hits" },
        { LPROC_LL_DIRTY_MISSES,   LPROCFS_TYPE_REGS, "dirty_pages_misses" },
        { LPROC_LL_READ_BYTES,     LPROCFS_CNTR_AVGMINMAX|LPROCFS_TYPE_BYTES,
                                   "read_bytes" },
        { LPROC_LL_WRITE_BYTES,    LPROCFS_CNTR_AVGMINMAX|LPROCFS_TYPE_BYTES,
                                   "write_bytes" },
        { LPROC_LL_BRW_READ,       LPROCFS_CNTR_AVGMINMAX|LPROCFS_TYPE_PAGES,
                                   "brw_read" },
        { LPROC_LL_BRW_WRITE,      LPROCFS_CNTR_AVGMINMAX|LPROCFS_TYPE_PAGES,
                                   "brw_write" },
        { LPROC_LL_IOCTL,          LPROCFS_TYPE_REGS, "ioctl" },
        { LPROC_LL_OPEN,           LPROCFS_TYPE_REGS, "open" },
        { LPROC_LL_RELEASE,        LPROCFS_TYPE_REGS, "close" },
        { LPROC_LL_MAP,            LPROCFS_TYPE_REGS, "mmap" },
	{ LPROC_LL_FAULT,          LPROCFS_TYPE_REGS, "page_fault" },
	{ LPROC_LL_MKWRITE,        LPROCFS_TYPE_REGS, "page_mkwrite" },
        { LPROC_LL_LLSEEK,         LPROCFS_TYPE_REGS, "seek" },
        { LPROC_LL_FSYNC,          LPROCFS_TYPE_REGS, "fsync" },
        { LPROC_LL_READDIR,        LPROCFS_TYPE_REGS, "readdir" },
        /* inode operation */
        { LPROC_LL_SETATTR,        LPROCFS_TYPE_REGS, "setattr" },
        { LPROC_LL_TRUNC,          LPROCFS_TYPE_REGS, "truncate" },
        { LPROC_LL_FLOCK,          LPROCFS_TYPE_REGS, "flock" },
        { LPROC_LL_GETATTR,        LPROCFS_TYPE_REGS, "getattr" },
        /* dir inode operation */
        { LPROC_LL_CREATE,         LPROCFS_TYPE_REGS, "create" },
        { LPROC_LL_LINK,           LPROCFS_TYPE_REGS, "link" },
        { LPROC_LL_UNLINK,         LPROCFS_TYPE_REGS, "unlink" },
        { LPROC_LL_SYMLINK,        LPROCFS_TYPE_REGS, "symlink" },
        { LPROC_LL_MKDIR,          LPROCFS_TYPE_REGS, "mkdir" },
        { LPROC_LL_RMDIR,          LPROCFS_TYPE_REGS, "rmdir" },
        { LPROC_LL_MKNOD,          LPROCFS_TYPE_REGS, "mknod" },
        { LPROC_LL_RENAME,         LPROCFS_TYPE_REGS, "rename" },
        /* special inode operation */
        { LPROC_LL_STAFS,          LPROCFS_TYPE_REGS, "statfs" },
        { LPROC_LL_ALLOC_INODE,    LPROCFS_TYPE_REGS, "alloc_inode" },
        { LPROC_LL_SETXATTR,       LPROCFS_TYPE_REGS, "setxattr" },
        { LPROC_LL_GETXATTR,       LPROCFS_TYPE_REGS, "getxattr" },
	{ LPROC_LL_GETXATTR_HITS,  LPROCFS_TYPE_REGS, "getxattr_hits" },
        { LPROC_LL_LISTXATTR,      LPROCFS_TYPE_REGS, "listxattr" },
        { LPROC_LL_REMOVEXATTR,    LPROCFS_TYPE_REGS, "removexattr" },
        { LPROC_LL_INODE_PERM,     LPROCFS_TYPE_REGS, "inode_permission" },
};

void ll_stats_ops_tally(struct ll_sb_info *sbi, int op, int count)
{
        if (!sbi->ll_stats)
                return;
        if (sbi->ll_stats_track_type == STATS_TRACK_ALL)
                lprocfs_counter_add(sbi->ll_stats, op, count);
        else if (sbi->ll_stats_track_type == STATS_TRACK_PID &&
                 sbi->ll_stats_track_id == current->pid)
                lprocfs_counter_add(sbi->ll_stats, op, count);
        else if (sbi->ll_stats_track_type == STATS_TRACK_PPID &&
                 sbi->ll_stats_track_id == current->parent->pid)
                lprocfs_counter_add(sbi->ll_stats, op, count);
	else if (sbi->ll_stats_track_type == STATS_TRACK_GID &&
		 sbi->ll_stats_track_id ==
			from_kgid(&init_user_ns, current_gid()))
		lprocfs_counter_add(sbi->ll_stats, op, count);
}
EXPORT_SYMBOL(ll_stats_ops_tally);

static const char *ra_stat_string[] = {
	[RA_STAT_HIT] = "hits",
	[RA_STAT_MISS] = "misses",
	[RA_STAT_DISTANT_READPAGE] = "readpage not consecutive",
	[RA_STAT_MISS_IN_WINDOW] = "miss inside window",
	[RA_STAT_FAILED_GRAB_PAGE] = "failed grab_cache_page",
	[RA_STAT_FAILED_MATCH] = "failed lock match",
	[RA_STAT_DISCARDED] = "read but discarded",
	[RA_STAT_ZERO_LEN] = "zero length file",
	[RA_STAT_ZERO_WINDOW] = "zero size window",
	[RA_STAT_EOF] = "read-ahead to EOF",
	[RA_STAT_MAX_IN_FLIGHT] = "hit max r-a issue",
	[RA_STAT_WRONG_GRAB_PAGE] = "wrong page from grab_cache_page",
	[RA_STAT_FAILED_REACH_END] = "failed to reach end"
};

int ll_debugfs_register_super(struct super_block *sb, const char *name)
{
	struct lustre_sb_info *lsi = s2lsi(sb);
	struct ll_sb_info *sbi = ll_s2sbi(sb);
	int err, id, rc;

	ENTRY;
	LASSERT(sbi);

	if (IS_ERR_OR_NULL(llite_root))
		goto out_ll_kset;

	sbi->ll_debugfs_entry = ldebugfs_register(name, llite_root,
						  lprocfs_llite_obd_vars, sb);
	if (IS_ERR_OR_NULL(sbi->ll_debugfs_entry)) {
		err = sbi->ll_debugfs_entry ? PTR_ERR(sbi->ll_debugfs_entry) :
					      -ENOMEM;
		sbi->ll_debugfs_entry = NULL;
		RETURN(err);
	}

	rc = ldebugfs_seq_create(sbi->ll_debugfs_entry, "dump_page_cache",0444,
				 &vvp_dump_pgcache_file_ops, sbi);
	if (rc)
		CWARN("Error adding the dump_page_cache file\n");

	rc = ldebugfs_seq_create(sbi->ll_debugfs_entry, "extents_stats", 0644,
				 &ll_rw_extents_stats_fops, sbi);
	if (rc)
		CWARN("Error adding the extent_stats file\n");

	rc = ldebugfs_seq_create(sbi->ll_debugfs_entry,
				 "extents_stats_per_process", 0644,
				 &ll_rw_extents_stats_pp_fops, sbi);
	if (rc)
		CWARN("Error adding the extents_stats_per_process file\n");

	rc = ldebugfs_seq_create(sbi->ll_debugfs_entry, "offset_stats", 0644,
				 &ll_rw_offset_stats_fops, sbi);
	if (rc)
		CWARN("Error adding the offset_stats file\n");

	/* File operations stats */
	sbi->ll_stats = lprocfs_alloc_stats(LPROC_LL_FILE_OPCODES,
					    LPROCFS_STATS_FLAG_NONE);
	if (sbi->ll_stats == NULL)
		GOTO(out_debugfs, err = -ENOMEM);

	/* do counter init */
	for (id = 0; id < LPROC_LL_FILE_OPCODES; id++) {
		u32 type = llite_opcode_table[id].type;
		void *ptr = NULL;

		if (type & LPROCFS_TYPE_REGS)
			ptr = "regs";
		else if (type & LPROCFS_TYPE_BYTES)
			ptr = "bytes";
		else if (type & LPROCFS_TYPE_PAGES)
			ptr = "pages";
		lprocfs_counter_init(sbi->ll_stats,
				     llite_opcode_table[id].opcode,
				     (type & LPROCFS_CNTR_AVGMINMAX),
				     llite_opcode_table[id].opname, ptr);
	}

	err = ldebugfs_register_stats(sbi->ll_debugfs_entry, "stats",
				      sbi->ll_stats);
	if (err)
		GOTO(out_stats, err);

	sbi->ll_ra_stats = lprocfs_alloc_stats(ARRAY_SIZE(ra_stat_string),
					       LPROCFS_STATS_FLAG_NONE);
	if (sbi->ll_ra_stats == NULL)
		GOTO(out_stats, err = -ENOMEM);

	for (id = 0; id < ARRAY_SIZE(ra_stat_string); id++)
		lprocfs_counter_init(sbi->ll_ra_stats, id, 0,
				     ra_stat_string[id], "pages");

	err = ldebugfs_register_stats(sbi->ll_debugfs_entry, "read_ahead_stats",
				      sbi->ll_ra_stats);
	if (err)
		GOTO(out_ra_stats, err);

out_ll_kset:
	/* Yes we also register sysfs mount kset here as well */
	sbi->ll_kset.kobj.parent = llite_kobj;
	sbi->ll_kset.kobj.ktype = &llite_ktype;
	init_completion(&sbi->ll_kobj_unregister);
	err = kobject_set_name(&sbi->ll_kset.kobj, "%s", name);
	if (err)
		GOTO(out_ra_stats, err);

	err = kset_register(&sbi->ll_kset);
	if (err)
		GOTO(out_ra_stats, err);

	lsi->lsi_kobj = kobject_get(&sbi->ll_kset.kobj);

	RETURN(0);
out_ra_stats:
	lprocfs_free_stats(&sbi->ll_ra_stats);
out_stats:
	lprocfs_free_stats(&sbi->ll_stats);
out_debugfs:
	ldebugfs_remove(&sbi->ll_debugfs_entry);

	RETURN(err);
}

void ll_debugfs_unregister_super(struct super_block *sb)
{
	struct lustre_sb_info *lsi = s2lsi(sb);
	struct ll_sb_info *sbi = ll_s2sbi(sb);

	if (!IS_ERR_OR_NULL(sbi->ll_debugfs_entry))
		ldebugfs_remove(&sbi->ll_debugfs_entry);

	if (sbi->ll_dt_obd)
		sysfs_remove_link(&sbi->ll_kset.kobj,
				  sbi->ll_dt_obd->obd_type->typ_name);

	if (sbi->ll_md_obd)
		sysfs_remove_link(&sbi->ll_kset.kobj,
				  sbi->ll_md_obd->obd_type->typ_name);

	kobject_put(lsi->lsi_kobj);

	kset_unregister(&sbi->ll_kset);
	wait_for_completion(&sbi->ll_kobj_unregister);

	lprocfs_free_stats(&sbi->ll_ra_stats);
	lprocfs_free_stats(&sbi->ll_stats);
}
#undef MAX_STRING_SIZE

static void ll_display_extents_info(struct ll_rw_extents_info *io_extents,
                                   struct seq_file *seq, int which)
{
        unsigned long read_tot = 0, write_tot = 0, read_cum, write_cum;
        unsigned long start, end, r, w;
        char *unitp = "KMGTPEZY";
        int i, units = 10;
        struct per_process_info *pp_info = &io_extents->pp_extents[which];

        read_cum = 0;
        write_cum = 0;
        start = 0;

        for(i = 0; i < LL_HIST_MAX; i++) {
                read_tot += pp_info->pp_r_hist.oh_buckets[i];
                write_tot += pp_info->pp_w_hist.oh_buckets[i];
        }

        for(i = 0; i < LL_HIST_MAX; i++) {
                r = pp_info->pp_r_hist.oh_buckets[i];
                w = pp_info->pp_w_hist.oh_buckets[i];
                read_cum += r;
                write_cum += w;
		end = BIT(i + LL_HIST_START - units);
		seq_printf(seq, "%4lu%c - %4lu%c%c: %14lu %4u %4u  | "
			   "%14lu %4u %4u\n", start, *unitp, end, *unitp,
                           (i == LL_HIST_MAX - 1) ? '+' : ' ',
                           r, pct(r, read_tot), pct(read_cum, read_tot),
                           w, pct(w, write_tot), pct(write_cum, write_tot));
                start = end;
		if (start == BIT(10)) {
                        start = 1;
                        units += 10;
                        unitp++;
                }
                if (read_cum == read_tot && write_cum == write_tot)
                        break;
        }
}

static int ll_rw_extents_stats_pp_seq_show(struct seq_file *seq, void *v)
{
	struct timespec64 now;
	struct ll_sb_info *sbi = seq->private;
	struct ll_rw_extents_info *io_extents = &sbi->ll_rw_extents_info;
	int k;

	ktime_get_real_ts64(&now);

	if (!sbi->ll_rw_stats_on) {
		seq_puts(seq, "disabled\n write anything to this file to activate, then '0' or 'disable' to deactivate\n");
		return 0;
	}
	seq_printf(seq, "snapshot_time:         %llu.%09lu (secs.nsecs)\n",
		   (s64)now.tv_sec, now.tv_nsec);
        seq_printf(seq, "%15s %19s       | %20s\n", " ", "read", "write");
        seq_printf(seq, "%13s   %14s %4s %4s  | %14s %4s %4s\n",
                   "extents", "calls", "%", "cum%",
                   "calls", "%", "cum%");
	spin_lock(&sbi->ll_pp_extent_lock);
	for (k = 0; k < LL_PROCESS_HIST_MAX; k++) {
		if (io_extents->pp_extents[k].pid != 0) {
			seq_printf(seq, "\nPID: %d\n",
				   io_extents->pp_extents[k].pid);
			ll_display_extents_info(io_extents, seq, k);
		}
	}
	spin_unlock(&sbi->ll_pp_extent_lock);
	return 0;
}

static ssize_t ll_rw_extents_stats_pp_seq_write(struct file *file,
						const char __user *buf,
						size_t len,
						loff_t *off)
{
	struct seq_file *seq = file->private_data;
	struct ll_sb_info *sbi = seq->private;
	struct ll_rw_extents_info *io_extents = &sbi->ll_rw_extents_info;
	int i;
	__s64 value;

	if (len == 0)
		return -EINVAL;

	value = ll_stats_pid_write(buf, len);

	if (value == 0)
		sbi->ll_rw_stats_on = 0;
	else
		sbi->ll_rw_stats_on = 1;

	spin_lock(&sbi->ll_pp_extent_lock);
	for (i = 0; i < LL_PROCESS_HIST_MAX; i++) {
		io_extents->pp_extents[i].pid = 0;
		lprocfs_oh_clear(&io_extents->pp_extents[i].pp_r_hist);
		lprocfs_oh_clear(&io_extents->pp_extents[i].pp_w_hist);
	}
	spin_unlock(&sbi->ll_pp_extent_lock);
	return len;
}

LDEBUGFS_SEQ_FOPS(ll_rw_extents_stats_pp);

static int ll_rw_extents_stats_seq_show(struct seq_file *seq, void *v)
{
	struct timespec64 now;
	struct ll_sb_info *sbi = seq->private;
	struct ll_rw_extents_info *io_extents = &sbi->ll_rw_extents_info;

	ktime_get_real_ts64(&now);

	if (!sbi->ll_rw_stats_on) {
		seq_puts(seq, "disabled\n write anything to this file to activate, then '0' or 'disable' to deactivate\n");
		return 0;
	}
	seq_printf(seq, "snapshot_time:         %llu.%09lu (secs.nsecs)\n",
		   (s64)now.tv_sec, now.tv_nsec);

	seq_printf(seq, "%15s %19s       | %20s\n", " ", "read", "write");
	seq_printf(seq, "%13s   %14s %4s %4s  | %14s %4s %4s\n",
		   "extents", "calls", "%", "cum%",
		   "calls", "%", "cum%");
	spin_lock(&sbi->ll_lock);
	ll_display_extents_info(io_extents, seq, LL_PROCESS_HIST_MAX);
	spin_unlock(&sbi->ll_lock);

	return 0;
}

static ssize_t ll_rw_extents_stats_seq_write(struct file *file,
					     const char __user *buf,
					     size_t len, loff_t *off)
{
	struct seq_file *seq = file->private_data;
	struct ll_sb_info *sbi = seq->private;
	struct ll_rw_extents_info *io_extents = &sbi->ll_rw_extents_info;
	int i;
	__s64 value;

	if (len == 0)
		return -EINVAL;

	value = ll_stats_pid_write(buf, len);

	if (value == 0)
		sbi->ll_rw_stats_on = 0;
	else
		sbi->ll_rw_stats_on = 1;

	spin_lock(&sbi->ll_pp_extent_lock);
	for (i = 0; i <= LL_PROCESS_HIST_MAX; i++) {
		io_extents->pp_extents[i].pid = 0;
		lprocfs_oh_clear(&io_extents->pp_extents[i].pp_r_hist);
		lprocfs_oh_clear(&io_extents->pp_extents[i].pp_w_hist);
	}
	spin_unlock(&sbi->ll_pp_extent_lock);

	return len;
}

LDEBUGFS_SEQ_FOPS(ll_rw_extents_stats);

void ll_rw_stats_tally(struct ll_sb_info *sbi, pid_t pid,
                       struct ll_file_data *file, loff_t pos,
                       size_t count, int rw)
{
        int i, cur = -1;
        struct ll_rw_process_info *process;
        struct ll_rw_process_info *offset;
        int *off_count = &sbi->ll_rw_offset_entry_count;
        int *process_count = &sbi->ll_offset_process_count;
        struct ll_rw_extents_info *io_extents = &sbi->ll_rw_extents_info;

        if(!sbi->ll_rw_stats_on)
                return;
        process = sbi->ll_rw_process_info;
        offset = sbi->ll_rw_offset_info;

	spin_lock(&sbi->ll_pp_extent_lock);
        /* Extent statistics */
        for(i = 0; i < LL_PROCESS_HIST_MAX; i++) {
                if(io_extents->pp_extents[i].pid == pid) {
                        cur = i;
                        break;
                }
        }

        if (cur == -1) {
                /* new process */
                sbi->ll_extent_process_count =
                        (sbi->ll_extent_process_count + 1) % LL_PROCESS_HIST_MAX;
                cur = sbi->ll_extent_process_count;
                io_extents->pp_extents[cur].pid = pid;
                lprocfs_oh_clear(&io_extents->pp_extents[cur].pp_r_hist);
                lprocfs_oh_clear(&io_extents->pp_extents[cur].pp_w_hist);
        }

	for(i = 0; (count >= BIT(LL_HIST_START << i)) &&
             (i < (LL_HIST_MAX - 1)); i++);
        if (rw == 0) {
                io_extents->pp_extents[cur].pp_r_hist.oh_buckets[i]++;
                io_extents->pp_extents[LL_PROCESS_HIST_MAX].pp_r_hist.oh_buckets[i]++;
        } else {
                io_extents->pp_extents[cur].pp_w_hist.oh_buckets[i]++;
                io_extents->pp_extents[LL_PROCESS_HIST_MAX].pp_w_hist.oh_buckets[i]++;
        }
	spin_unlock(&sbi->ll_pp_extent_lock);

	spin_lock(&sbi->ll_process_lock);
        /* Offset statistics */
        for (i = 0; i < LL_PROCESS_HIST_MAX; i++) {
                if (process[i].rw_pid == pid) {
                        if (process[i].rw_last_file != file) {
                                process[i].rw_range_start = pos;
                                process[i].rw_last_file_pos = pos + count;
                                process[i].rw_smallest_extent = count;
                                process[i].rw_largest_extent = count;
                                process[i].rw_offset = 0;
                                process[i].rw_last_file = file;
				spin_unlock(&sbi->ll_process_lock);
                                return;
                        }
                        if (process[i].rw_last_file_pos != pos) {
                                *off_count =
                                    (*off_count + 1) % LL_OFFSET_HIST_MAX;
                                offset[*off_count].rw_op = process[i].rw_op;
                                offset[*off_count].rw_pid = pid;
                                offset[*off_count].rw_range_start =
                                        process[i].rw_range_start;
                                offset[*off_count].rw_range_end =
                                        process[i].rw_last_file_pos;
                                offset[*off_count].rw_smallest_extent =
                                        process[i].rw_smallest_extent;
                                offset[*off_count].rw_largest_extent =
                                        process[i].rw_largest_extent;
                                offset[*off_count].rw_offset =
                                        process[i].rw_offset;
                                process[i].rw_op = rw;
                                process[i].rw_range_start = pos;
                                process[i].rw_smallest_extent = count;
                                process[i].rw_largest_extent = count;
                                process[i].rw_offset = pos -
                                        process[i].rw_last_file_pos;
                        }
                        if(process[i].rw_smallest_extent > count)
                                process[i].rw_smallest_extent = count;
                        if(process[i].rw_largest_extent < count)
                                process[i].rw_largest_extent = count;
                        process[i].rw_last_file_pos = pos + count;
			spin_unlock(&sbi->ll_process_lock);
                        return;
                }
        }
        *process_count = (*process_count + 1) % LL_PROCESS_HIST_MAX;
        process[*process_count].rw_pid = pid;
        process[*process_count].rw_op = rw;
        process[*process_count].rw_range_start = pos;
        process[*process_count].rw_last_file_pos = pos + count;
        process[*process_count].rw_smallest_extent = count;
        process[*process_count].rw_largest_extent = count;
        process[*process_count].rw_offset = 0;
        process[*process_count].rw_last_file = file;
	spin_unlock(&sbi->ll_process_lock);
}

static int ll_rw_offset_stats_seq_show(struct seq_file *seq, void *v)
{
	struct timespec64 now;
	struct ll_sb_info *sbi = seq->private;
	struct ll_rw_process_info *offset = sbi->ll_rw_offset_info;
	struct ll_rw_process_info *process = sbi->ll_rw_process_info;
	int i;

	ktime_get_real_ts64(&now);

	if (!sbi->ll_rw_stats_on) {
		seq_puts(seq, "disabled\n write anything to this file to activate, then '0' or 'disable' to deactivate\n");
		return 0;
	}
	spin_lock(&sbi->ll_process_lock);

	seq_printf(seq, "snapshot_time:         %llu.%09lu (secs.nsecs)\n",
		   (s64)now.tv_sec, now.tv_nsec);
	seq_printf(seq, "%3s %10s %14s %14s %17s %17s %14s\n",
		   "R/W", "PID", "RANGE START", "RANGE END",
		   "SMALLEST EXTENT", "LARGEST EXTENT", "OFFSET");

	/* We stored the discontiguous offsets here; print them first */
	for (i = 0; i < LL_OFFSET_HIST_MAX; i++) {
		if (offset[i].rw_pid != 0)
			seq_printf(seq,
				  "%3c %10d %14llu %14llu %17lu %17lu %14llu\n",
				   offset[i].rw_op == READ ? 'R' : 'W',
				   offset[i].rw_pid,
				   offset[i].rw_range_start,
				   offset[i].rw_range_end,
				   (unsigned long)offset[i].rw_smallest_extent,
				   (unsigned long)offset[i].rw_largest_extent,
				   offset[i].rw_offset);
	}

	/* Then print the current offsets for each process */
	for (i = 0; i < LL_PROCESS_HIST_MAX; i++) {
		if (process[i].rw_pid != 0)
			seq_printf(seq,
				  "%3c %10d %14llu %14llu %17lu %17lu %14llu\n",
				   process[i].rw_op == READ ? 'R' : 'W',
				   process[i].rw_pid,
				   process[i].rw_range_start,
				   process[i].rw_last_file_pos,
				   (unsigned long)process[i].rw_smallest_extent,
				   (unsigned long)process[i].rw_largest_extent,
				   process[i].rw_offset);
	}
	spin_unlock(&sbi->ll_process_lock);

	return 0;
}

static ssize_t ll_rw_offset_stats_seq_write(struct file *file,
					    const char __user *buf,
					    size_t len, loff_t *off)
{
	struct seq_file *seq = file->private_data;
	struct ll_sb_info *sbi = seq->private;
	struct ll_rw_process_info *process_info = sbi->ll_rw_process_info;
	struct ll_rw_process_info *offset_info = sbi->ll_rw_offset_info;
	__s64 value;

	if (len == 0)
		return -EINVAL;

	value = ll_stats_pid_write(buf, len);

	if (value == 0)
		sbi->ll_rw_stats_on = 0;
	else
		sbi->ll_rw_stats_on = 1;

	spin_lock(&sbi->ll_process_lock);
	sbi->ll_offset_process_count = 0;
	sbi->ll_rw_offset_entry_count = 0;
	memset(process_info, 0, sizeof(struct ll_rw_process_info) *
	       LL_PROCESS_HIST_MAX);
	memset(offset_info, 0, sizeof(struct ll_rw_process_info) *
	       LL_OFFSET_HIST_MAX);
	spin_unlock(&sbi->ll_process_lock);

	return len;
}

LDEBUGFS_SEQ_FOPS(ll_rw_offset_stats);