sysfs.c 21.2 KB
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C
Chris Mason 已提交
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/*
 * Copyright (C) 2007 Oracle.  All rights reserved.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public
 * License v2 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 for more details.
 *
 * You should have received a copy of the GNU General Public
 * License along with this program; if not, write to the
 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
 * Boston, MA 021110-1307, USA.
 */

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#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <linux/completion.h>
#include <linux/buffer_head.h>
#include <linux/kobject.h>
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#include <linux/bug.h>
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#include <linux/genhd.h>
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#include <linux/debugfs.h>
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#include "ctree.h"
#include "disk-io.h"
#include "transaction.h"
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#include "sysfs.h"
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#include "volumes.h"
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static inline struct btrfs_fs_info *to_fs_info(struct kobject *kobj);
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static inline struct btrfs_fs_devices *to_fs_devs(struct kobject *kobj);
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static u64 get_features(struct btrfs_fs_info *fs_info,
			enum btrfs_feature_set set)
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{
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	struct btrfs_super_block *disk_super = fs_info->super_copy;
	if (set == FEAT_COMPAT)
		return btrfs_super_compat_flags(disk_super);
	else if (set == FEAT_COMPAT_RO)
		return btrfs_super_compat_ro_flags(disk_super);
	else
		return btrfs_super_incompat_flags(disk_super);
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}

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static void set_features(struct btrfs_fs_info *fs_info,
			 enum btrfs_feature_set set, u64 features)
{
	struct btrfs_super_block *disk_super = fs_info->super_copy;
	if (set == FEAT_COMPAT)
		btrfs_set_super_compat_flags(disk_super, features);
	else if (set == FEAT_COMPAT_RO)
		btrfs_set_super_compat_ro_flags(disk_super, features);
	else
		btrfs_set_super_incompat_flags(disk_super, features);
}

static int can_modify_feature(struct btrfs_feature_attr *fa)
{
	int val = 0;
	u64 set, clear;
	switch (fa->feature_set) {
	case FEAT_COMPAT:
		set = BTRFS_FEATURE_COMPAT_SAFE_SET;
		clear = BTRFS_FEATURE_COMPAT_SAFE_CLEAR;
		break;
	case FEAT_COMPAT_RO:
		set = BTRFS_FEATURE_COMPAT_RO_SAFE_SET;
		clear = BTRFS_FEATURE_COMPAT_RO_SAFE_CLEAR;
		break;
	case FEAT_INCOMPAT:
		set = BTRFS_FEATURE_INCOMPAT_SAFE_SET;
		clear = BTRFS_FEATURE_INCOMPAT_SAFE_CLEAR;
		break;
	default:
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		printk(KERN_WARNING "btrfs: sysfs: unknown feature set %d\n",
				fa->feature_set);
		return 0;
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	}

	if (set & fa->feature_bit)
		val |= 1;
	if (clear & fa->feature_bit)
		val |= 2;

	return val;
}

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static ssize_t btrfs_feature_attr_show(struct kobject *kobj,
				       struct kobj_attribute *a, char *buf)
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{
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	int val = 0;
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	struct btrfs_fs_info *fs_info = to_fs_info(kobj);
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	struct btrfs_feature_attr *fa = to_btrfs_feature_attr(a);
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	if (fs_info) {
		u64 features = get_features(fs_info, fa->feature_set);
		if (features & fa->feature_bit)
			val = 1;
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	} else
		val = can_modify_feature(fa);
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	return snprintf(buf, PAGE_SIZE, "%d\n", val);
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}

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static ssize_t btrfs_feature_attr_store(struct kobject *kobj,
					struct kobj_attribute *a,
					const char *buf, size_t count)
{
	struct btrfs_fs_info *fs_info;
	struct btrfs_feature_attr *fa = to_btrfs_feature_attr(a);
	u64 features, set, clear;
	unsigned long val;
	int ret;

	fs_info = to_fs_info(kobj);
	if (!fs_info)
		return -EPERM;

	ret = kstrtoul(skip_spaces(buf), 0, &val);
	if (ret)
		return ret;

	if (fa->feature_set == FEAT_COMPAT) {
		set = BTRFS_FEATURE_COMPAT_SAFE_SET;
		clear = BTRFS_FEATURE_COMPAT_SAFE_CLEAR;
	} else if (fa->feature_set == FEAT_COMPAT_RO) {
		set = BTRFS_FEATURE_COMPAT_RO_SAFE_SET;
		clear = BTRFS_FEATURE_COMPAT_RO_SAFE_CLEAR;
	} else {
		set = BTRFS_FEATURE_INCOMPAT_SAFE_SET;
		clear = BTRFS_FEATURE_INCOMPAT_SAFE_CLEAR;
	}

	features = get_features(fs_info, fa->feature_set);

	/* Nothing to do */
	if ((val && (features & fa->feature_bit)) ||
	    (!val && !(features & fa->feature_bit)))
		return count;

	if ((val && !(set & fa->feature_bit)) ||
	    (!val && !(clear & fa->feature_bit))) {
		btrfs_info(fs_info,
			"%sabling feature %s on mounted fs is not supported.",
			val ? "En" : "Dis", fa->kobj_attr.attr.name);
		return -EPERM;
	}

	btrfs_info(fs_info, "%s %s feature flag",
		   val ? "Setting" : "Clearing", fa->kobj_attr.attr.name);

	spin_lock(&fs_info->super_lock);
	features = get_features(fs_info, fa->feature_set);
	if (val)
		features |= fa->feature_bit;
	else
		features &= ~fa->feature_bit;
	set_features(fs_info, fa->feature_set, features);
	spin_unlock(&fs_info->super_lock);

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	/*
	 * We don't want to do full transaction commit from inside sysfs
	 */
	btrfs_set_pending(fs_info, COMMIT);
	wake_up_process(fs_info->transaction_kthread);
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	return count;
}

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static umode_t btrfs_feature_visible(struct kobject *kobj,
				     struct attribute *attr, int unused)
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{
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	struct btrfs_fs_info *fs_info = to_fs_info(kobj);
	umode_t mode = attr->mode;

	if (fs_info) {
		struct btrfs_feature_attr *fa;
		u64 features;

		fa = attr_to_btrfs_feature_attr(attr);
		features = get_features(fs_info, fa->feature_set);

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		if (can_modify_feature(fa))
			mode |= S_IWUSR;
		else if (!(features & fa->feature_bit))
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			mode = 0;
	}

	return mode;
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}

BTRFS_FEAT_ATTR_INCOMPAT(mixed_backref, MIXED_BACKREF);
BTRFS_FEAT_ATTR_INCOMPAT(default_subvol, DEFAULT_SUBVOL);
BTRFS_FEAT_ATTR_INCOMPAT(mixed_groups, MIXED_GROUPS);
BTRFS_FEAT_ATTR_INCOMPAT(compress_lzo, COMPRESS_LZO);
BTRFS_FEAT_ATTR_INCOMPAT(big_metadata, BIG_METADATA);
BTRFS_FEAT_ATTR_INCOMPAT(extended_iref, EXTENDED_IREF);
BTRFS_FEAT_ATTR_INCOMPAT(raid56, RAID56);
BTRFS_FEAT_ATTR_INCOMPAT(skinny_metadata, SKINNY_METADATA);
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BTRFS_FEAT_ATTR_INCOMPAT(no_holes, NO_HOLES);
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static struct attribute *btrfs_supported_feature_attrs[] = {
	BTRFS_FEAT_ATTR_PTR(mixed_backref),
	BTRFS_FEAT_ATTR_PTR(default_subvol),
	BTRFS_FEAT_ATTR_PTR(mixed_groups),
	BTRFS_FEAT_ATTR_PTR(compress_lzo),
	BTRFS_FEAT_ATTR_PTR(big_metadata),
	BTRFS_FEAT_ATTR_PTR(extended_iref),
	BTRFS_FEAT_ATTR_PTR(raid56),
	BTRFS_FEAT_ATTR_PTR(skinny_metadata),
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	BTRFS_FEAT_ATTR_PTR(no_holes),
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	NULL
};

static const struct attribute_group btrfs_feature_attr_group = {
	.name = "features",
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	.is_visible = btrfs_feature_visible,
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	.attrs = btrfs_supported_feature_attrs,
};
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static ssize_t btrfs_show_u64(u64 *value_ptr, spinlock_t *lock, char *buf)
{
	u64 val;
	if (lock)
		spin_lock(lock);
	val = *value_ptr;
	if (lock)
		spin_unlock(lock);
	return snprintf(buf, PAGE_SIZE, "%llu\n", val);
}

static ssize_t global_rsv_size_show(struct kobject *kobj,
				    struct kobj_attribute *ka, char *buf)
{
	struct btrfs_fs_info *fs_info = to_fs_info(kobj->parent);
	struct btrfs_block_rsv *block_rsv = &fs_info->global_block_rsv;
	return btrfs_show_u64(&block_rsv->size, &block_rsv->lock, buf);
}
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BTRFS_ATTR(global_rsv_size, global_rsv_size_show);
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static ssize_t global_rsv_reserved_show(struct kobject *kobj,
					struct kobj_attribute *a, char *buf)
{
	struct btrfs_fs_info *fs_info = to_fs_info(kobj->parent);
	struct btrfs_block_rsv *block_rsv = &fs_info->global_block_rsv;
	return btrfs_show_u64(&block_rsv->reserved, &block_rsv->lock, buf);
}
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BTRFS_ATTR(global_rsv_reserved, global_rsv_reserved_show);
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#define to_space_info(_kobj) container_of(_kobj, struct btrfs_space_info, kobj)
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#define to_raid_kobj(_kobj) container_of(_kobj, struct raid_kobject, kobj)
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static ssize_t raid_bytes_show(struct kobject *kobj,
			       struct kobj_attribute *attr, char *buf);
BTRFS_RAID_ATTR(total_bytes, raid_bytes_show);
BTRFS_RAID_ATTR(used_bytes, raid_bytes_show);

static ssize_t raid_bytes_show(struct kobject *kobj,
			       struct kobj_attribute *attr, char *buf)

{
	struct btrfs_space_info *sinfo = to_space_info(kobj->parent);
	struct btrfs_block_group_cache *block_group;
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	int index = to_raid_kobj(kobj)->raid_type;
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	u64 val = 0;

	down_read(&sinfo->groups_sem);
	list_for_each_entry(block_group, &sinfo->block_groups[index], list) {
		if (&attr->attr == BTRFS_RAID_ATTR_PTR(total_bytes))
			val += block_group->key.offset;
		else
			val += btrfs_block_group_used(&block_group->item);
	}
	up_read(&sinfo->groups_sem);
	return snprintf(buf, PAGE_SIZE, "%llu\n", val);
}

static struct attribute *raid_attributes[] = {
	BTRFS_RAID_ATTR_PTR(total_bytes),
	BTRFS_RAID_ATTR_PTR(used_bytes),
	NULL
};

static void release_raid_kobj(struct kobject *kobj)
{
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	kfree(to_raid_kobj(kobj));
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}

struct kobj_type btrfs_raid_ktype = {
	.sysfs_ops = &kobj_sysfs_ops,
	.release = release_raid_kobj,
	.default_attrs = raid_attributes,
};

#define SPACE_INFO_ATTR(field)						\
static ssize_t btrfs_space_info_show_##field(struct kobject *kobj,	\
					     struct kobj_attribute *a,	\
					     char *buf)			\
{									\
	struct btrfs_space_info *sinfo = to_space_info(kobj);		\
	return btrfs_show_u64(&sinfo->field, &sinfo->lock, buf);	\
}									\
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BTRFS_ATTR(field, btrfs_space_info_show_##field)
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static ssize_t btrfs_space_info_show_total_bytes_pinned(struct kobject *kobj,
						       struct kobj_attribute *a,
						       char *buf)
{
	struct btrfs_space_info *sinfo = to_space_info(kobj);
	s64 val = percpu_counter_sum(&sinfo->total_bytes_pinned);
	return snprintf(buf, PAGE_SIZE, "%lld\n", val);
}

SPACE_INFO_ATTR(flags);
SPACE_INFO_ATTR(total_bytes);
SPACE_INFO_ATTR(bytes_used);
SPACE_INFO_ATTR(bytes_pinned);
SPACE_INFO_ATTR(bytes_reserved);
SPACE_INFO_ATTR(bytes_may_use);
SPACE_INFO_ATTR(disk_used);
SPACE_INFO_ATTR(disk_total);
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BTRFS_ATTR(total_bytes_pinned, btrfs_space_info_show_total_bytes_pinned);
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static struct attribute *space_info_attrs[] = {
	BTRFS_ATTR_PTR(flags),
	BTRFS_ATTR_PTR(total_bytes),
	BTRFS_ATTR_PTR(bytes_used),
	BTRFS_ATTR_PTR(bytes_pinned),
	BTRFS_ATTR_PTR(bytes_reserved),
	BTRFS_ATTR_PTR(bytes_may_use),
	BTRFS_ATTR_PTR(disk_used),
	BTRFS_ATTR_PTR(disk_total),
	BTRFS_ATTR_PTR(total_bytes_pinned),
	NULL,
};

static void space_info_release(struct kobject *kobj)
{
	struct btrfs_space_info *sinfo = to_space_info(kobj);
	percpu_counter_destroy(&sinfo->total_bytes_pinned);
	kfree(sinfo);
}

struct kobj_type space_info_ktype = {
	.sysfs_ops = &kobj_sysfs_ops,
	.release = space_info_release,
	.default_attrs = space_info_attrs,
};

static const struct attribute *allocation_attrs[] = {
	BTRFS_ATTR_PTR(global_rsv_reserved),
	BTRFS_ATTR_PTR(global_rsv_size),
	NULL,
};

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static ssize_t btrfs_label_show(struct kobject *kobj,
				struct kobj_attribute *a, char *buf)
{
	struct btrfs_fs_info *fs_info = to_fs_info(kobj);
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	char *label = fs_info->super_copy->label;
	return snprintf(buf, PAGE_SIZE, label[0] ? "%s\n" : "%s", label);
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}

static ssize_t btrfs_label_store(struct kobject *kobj,
				 struct kobj_attribute *a,
				 const char *buf, size_t len)
{
	struct btrfs_fs_info *fs_info = to_fs_info(kobj);
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	size_t p_len;
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	if (fs_info->sb->s_flags & MS_RDONLY)
		return -EROFS;

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	/*
	 * p_len is the len until the first occurrence of either
	 * '\n' or '\0'
	 */
	p_len = strcspn(buf, "\n");

	if (p_len >= BTRFS_LABEL_SIZE)
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		return -EINVAL;

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	spin_lock(&fs_info->super_lock);
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	memset(fs_info->super_copy->label, 0, BTRFS_LABEL_SIZE);
	memcpy(fs_info->super_copy->label, buf, p_len);
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	spin_unlock(&fs_info->super_lock);
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	/*
	 * We don't want to do full transaction commit from inside sysfs
	 */
	btrfs_set_pending(fs_info, COMMIT);
	wake_up_process(fs_info->transaction_kthread);
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	return len;
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}
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BTRFS_ATTR_RW(label, btrfs_label_show, btrfs_label_store);
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static ssize_t btrfs_nodesize_show(struct kobject *kobj,
				struct kobj_attribute *a, char *buf)
{
	struct btrfs_fs_info *fs_info = to_fs_info(kobj);

	return snprintf(buf, PAGE_SIZE, "%u\n", fs_info->super_copy->nodesize);
}

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BTRFS_ATTR(nodesize, btrfs_nodesize_show);
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static ssize_t btrfs_sectorsize_show(struct kobject *kobj,
				struct kobj_attribute *a, char *buf)
{
	struct btrfs_fs_info *fs_info = to_fs_info(kobj);

	return snprintf(buf, PAGE_SIZE, "%u\n", fs_info->super_copy->sectorsize);
}

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BTRFS_ATTR(sectorsize, btrfs_sectorsize_show);
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static ssize_t btrfs_clone_alignment_show(struct kobject *kobj,
				struct kobj_attribute *a, char *buf)
{
	struct btrfs_fs_info *fs_info = to_fs_info(kobj);

	return snprintf(buf, PAGE_SIZE, "%u\n", fs_info->super_copy->sectorsize);
}

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BTRFS_ATTR(clone_alignment, btrfs_clone_alignment_show);
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static const struct attribute *btrfs_attrs[] = {
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	BTRFS_ATTR_PTR(label),
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	BTRFS_ATTR_PTR(nodesize),
	BTRFS_ATTR_PTR(sectorsize),
	BTRFS_ATTR_PTR(clone_alignment),
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	NULL,
};

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static void btrfs_release_super_kobj(struct kobject *kobj)
{
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	struct btrfs_fs_devices *fs_devs = to_fs_devs(kobj);
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	memset(&fs_devs->super_kobj, 0, sizeof(struct kobject));
	complete(&fs_devs->kobj_unregister);
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}

static struct kobj_type btrfs_ktype = {
	.sysfs_ops	= &kobj_sysfs_ops,
	.release	= btrfs_release_super_kobj,
};

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static inline struct btrfs_fs_devices *to_fs_devs(struct kobject *kobj)
{
	if (kobj->ktype != &btrfs_ktype)
		return NULL;
	return container_of(kobj, struct btrfs_fs_devices, super_kobj);
}

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static inline struct btrfs_fs_info *to_fs_info(struct kobject *kobj)
{
	if (kobj->ktype != &btrfs_ktype)
		return NULL;
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	return to_fs_devs(kobj)->fs_info;
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}
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#define NUM_FEATURE_BITS 64
static char btrfs_unknown_feature_names[3][NUM_FEATURE_BITS][13];
static struct btrfs_feature_attr btrfs_feature_attrs[3][NUM_FEATURE_BITS];

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static const u64 supported_feature_masks[3] = {
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	[FEAT_COMPAT]    = BTRFS_FEATURE_COMPAT_SUPP,
	[FEAT_COMPAT_RO] = BTRFS_FEATURE_COMPAT_RO_SUPP,
	[FEAT_INCOMPAT]  = BTRFS_FEATURE_INCOMPAT_SUPP,
};

static int addrm_unknown_feature_attrs(struct btrfs_fs_info *fs_info, bool add)
{
	int set;

	for (set = 0; set < FEAT_MAX; set++) {
		int i;
		struct attribute *attrs[2];
		struct attribute_group agroup = {
			.name = "features",
			.attrs = attrs,
		};
		u64 features = get_features(fs_info, set);
		features &= ~supported_feature_masks[set];

		if (!features)
			continue;

		attrs[1] = NULL;
		for (i = 0; i < NUM_FEATURE_BITS; i++) {
			struct btrfs_feature_attr *fa;

			if (!(features & (1ULL << i)))
				continue;

			fa = &btrfs_feature_attrs[set][i];
			attrs[0] = &fa->kobj_attr.attr;
			if (add) {
				int ret;
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				ret = sysfs_merge_group(&fs_info->fs_devices->super_kobj,
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							&agroup);
				if (ret)
					return ret;
			} else
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				sysfs_unmerge_group(&fs_info->fs_devices->super_kobj,
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						    &agroup);
		}

	}
	return 0;
}

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static void __btrfs_sysfs_remove_fsid(struct btrfs_fs_devices *fs_devs)
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{
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	if (fs_devs->device_dir_kobj) {
		kobject_del(fs_devs->device_dir_kobj);
		kobject_put(fs_devs->device_dir_kobj);
		fs_devs->device_dir_kobj = NULL;
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	}

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	kobject_del(&fs_devs->super_kobj);
	kobject_put(&fs_devs->super_kobj);
	wait_for_completion(&fs_devs->kobj_unregister);
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}

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/* when fs_devs is NULL it will remove all fsid kobject */
static void btrfs_sysfs_remove_fsid(struct btrfs_fs_devices *fs_devs)
{
	struct list_head *fs_uuids = btrfs_get_fs_uuids();

	if (fs_devs) {
		__btrfs_sysfs_remove_fsid(fs_devs);
		return;
	}

	list_for_each_entry(fs_devs, fs_uuids, list) {
		__btrfs_sysfs_remove_fsid(fs_devs);
	}
}

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void btrfs_sysfs_remove_one(struct btrfs_fs_info *fs_info)
{
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	btrfs_reset_fs_info_ptr(fs_info);

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	if (fs_info->space_info_kobj) {
		sysfs_remove_files(fs_info->space_info_kobj, allocation_attrs);
		kobject_del(fs_info->space_info_kobj);
		kobject_put(fs_info->space_info_kobj);
	}
	addrm_unknown_feature_attrs(fs_info, false);
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	sysfs_remove_group(&fs_info->fs_devices->super_kobj, &btrfs_feature_attr_group);
	sysfs_remove_files(&fs_info->fs_devices->super_kobj, btrfs_attrs);
	btrfs_kobj_rm_device(fs_info, NULL);
	btrfs_sysfs_remove_fsid(fs_info->fs_devices);
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}

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const char * const btrfs_feature_set_names[3] = {
	[FEAT_COMPAT]	 = "compat",
	[FEAT_COMPAT_RO] = "compat_ro",
	[FEAT_INCOMPAT]	 = "incompat",
};

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char *btrfs_printable_features(enum btrfs_feature_set set, u64 flags)
{
	size_t bufsize = 4096; /* safe max, 64 names * 64 bytes */
	int len = 0;
	int i;
	char *str;

	str = kmalloc(bufsize, GFP_KERNEL);
	if (!str)
		return str;

	for (i = 0; i < ARRAY_SIZE(btrfs_feature_attrs[set]); i++) {
		const char *name;

		if (!(flags & (1ULL << i)))
			continue;

		name = btrfs_feature_attrs[set][i].kobj_attr.attr.name;
		len += snprintf(str + len, bufsize - len, "%s%s",
				len ? "," : "", name);
	}

	return str;
}

593 594 595 596 597 598 599 600 601 602
static void init_feature_attrs(void)
{
	struct btrfs_feature_attr *fa;
	int set, i;

	BUILD_BUG_ON(ARRAY_SIZE(btrfs_unknown_feature_names) !=
		     ARRAY_SIZE(btrfs_feature_attrs));
	BUILD_BUG_ON(ARRAY_SIZE(btrfs_unknown_feature_names[0]) !=
		     ARRAY_SIZE(btrfs_feature_attrs[0]));

603 604 605 606
	memset(btrfs_feature_attrs, 0, sizeof(btrfs_feature_attrs));
	memset(btrfs_unknown_feature_names, 0,
	       sizeof(btrfs_unknown_feature_names));

607 608 609
	for (i = 0; btrfs_supported_feature_attrs[i]; i++) {
		struct btrfs_feature_attr *sfa;
		struct attribute *a = btrfs_supported_feature_attrs[i];
610
		int bit;
611
		sfa = attr_to_btrfs_feature_attr(a);
612 613
		bit = ilog2(sfa->feature_bit);
		fa = &btrfs_feature_attrs[sfa->feature_set][bit];
614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636

		fa->kobj_attr.attr.name = sfa->kobj_attr.attr.name;
	}

	for (set = 0; set < FEAT_MAX; set++) {
		for (i = 0; i < ARRAY_SIZE(btrfs_feature_attrs[set]); i++) {
			char *name = btrfs_unknown_feature_names[set][i];
			fa = &btrfs_feature_attrs[set][i];

			if (fa->kobj_attr.attr.name)
				continue;

			snprintf(name, 13, "%s:%u",
				 btrfs_feature_set_names[set], i);

			fa->kobj_attr.attr.name = name;
			fa->kobj_attr.attr.mode = S_IRUGO;
			fa->feature_set = set;
			fa->feature_bit = 1ULL << i;
		}
	}
}

637 638
/* when one_device is NULL, it removes all device links */

639 640 641 642 643 644
int btrfs_kobj_rm_device(struct btrfs_fs_info *fs_info,
		struct btrfs_device *one_device)
{
	struct hd_struct *disk;
	struct kobject *disk_kobj;

645
	if (!fs_info->fs_devices->device_dir_kobj)
646 647
		return -EINVAL;

648
	if (one_device && one_device->bdev) {
649 650 651
		disk = one_device->bdev->bd_part;
		disk_kobj = &part_to_dev(disk)->kobj;

652
		sysfs_remove_link(fs_info->fs_devices->device_dir_kobj,
653 654 655
						disk_kobj->name);
	}

656 657 658 659 660 661 662 663 664 665
	if (one_device)
		return 0;

	list_for_each_entry(one_device,
			&fs_info->fs_devices->devices, dev_list) {
		if (!one_device->bdev)
			continue;
		disk = one_device->bdev->bd_part;
		disk_kobj = &part_to_dev(disk)->kobj;

666
		sysfs_remove_link(fs_info->fs_devices->device_dir_kobj,
667 668 669
						disk_kobj->name);
	}

670 671 672
	return 0;
}

673
int btrfs_sysfs_add_device(struct btrfs_fs_devices *fs_devs)
674
{
675 676 677
	if (!fs_devs->device_dir_kobj)
		fs_devs->device_dir_kobj = kobject_create_and_add("devices",
						&fs_devs->super_kobj);
678

679
	if (!fs_devs->device_dir_kobj)
680 681
		return -ENOMEM;

682 683 684
	return 0;
}

685 686
int btrfs_kobj_add_device(struct btrfs_fs_devices *fs_devices,
				struct btrfs_device *one_device)
687 688 689 690
{
	int error = 0;
	struct btrfs_device *dev;

691
	error = btrfs_sysfs_add_device(fs_devices);
692 693 694
	if (error)
		return error;

695
	list_for_each_entry(dev, &fs_devices->devices, dev_list) {
696 697 698 699 700 701
		struct hd_struct *disk;
		struct kobject *disk_kobj;

		if (!dev->bdev)
			continue;

702 703 704
		if (one_device && one_device != dev)
			continue;

705 706
		disk = dev->bdev->bd_part;
		disk_kobj = &part_to_dev(disk)->kobj;
707

708
		error = sysfs_create_link(fs_devices->device_dir_kobj,
709 710 711 712 713 714 715 716
					  disk_kobj, disk_kobj->name);
		if (error)
			break;
	}

	return error;
}

717 718 719
/* /sys/fs/btrfs/ entry */
static struct kset *btrfs_kset;

720 721 722 723 724 725
/* /sys/kernel/debug/btrfs */
static struct dentry *btrfs_debugfs_root_dentry;

/* Debugging tunables and exported data */
u64 btrfs_debugfs_test;

726 727 728 729
/*
 * Can be called by the device discovery thread.
 * And parent can be specified for seed device
 */
730
static int btrfs_sysfs_add_fsid(struct btrfs_fs_devices *fs_devs,
731
				struct kobject *parent)
732 733 734
{
	int error;

735 736 737 738
	init_completion(&fs_devs->kobj_unregister);
	fs_devs->super_kobj.kset = btrfs_kset;
	error = kobject_init_and_add(&fs_devs->super_kobj, &btrfs_ktype, NULL,
				     "%pU", fs_devs->fsid);
739 740 741 742 743 744
	return error;
}

int btrfs_sysfs_add_one(struct btrfs_fs_info *fs_info)
{
	int error;
745 746
	struct btrfs_fs_devices *fs_devs = fs_info->fs_devices;
	struct kobject *super_kobj = &fs_devs->super_kobj;
747

748 749
	btrfs_set_fs_info_ptr(fs_info);

750
	error = btrfs_sysfs_add_fsid(fs_devs, NULL);
751 752
	if (error)
		return error;
753

754
	error = btrfs_kobj_add_device(fs_devs, NULL);
755
	if (error) {
756
		btrfs_sysfs_remove_fsid(fs_devs);
757 758 759
		return error;
	}

760
	error = sysfs_create_files(super_kobj, btrfs_attrs);
761
	if (error) {
762
		btrfs_sysfs_remove_fsid(fs_devs);
763 764
		return error;
	}
765

766
	error = sysfs_create_group(super_kobj,
767 768 769 770
				   &btrfs_feature_attr_group);
	if (error)
		goto failure;

771
	error = addrm_unknown_feature_attrs(fs_info, true);
772 773 774
	if (error)
		goto failure;

775
	fs_info->space_info_kobj = kobject_create_and_add("allocation",
776
						  super_kobj);
777 778 779 780 781 782 783 784 785
	if (!fs_info->space_info_kobj) {
		error = -ENOMEM;
		goto failure;
	}

	error = sysfs_create_files(fs_info->space_info_kobj, allocation_attrs);
	if (error)
		goto failure;

786 787 788
	return 0;
failure:
	btrfs_sysfs_remove_one(fs_info);
789 790 791
	return error;
}

792 793 794 795 796 797 798 799 800 801 802 803 804
static int btrfs_init_debugfs(void)
{
#ifdef CONFIG_DEBUG_FS
	btrfs_debugfs_root_dentry = debugfs_create_dir("btrfs", NULL);
	if (!btrfs_debugfs_root_dentry)
		return -ENOMEM;

	debugfs_create_u64("test", S_IRUGO | S_IWUGO, btrfs_debugfs_root_dentry,
			&btrfs_debugfs_test);
#endif
	return 0;
}

C
Christoph Hellwig 已提交
805
int btrfs_init_sysfs(void)
806
{
807
	int ret;
808

809 810 811
	btrfs_kset = kset_create_and_add("btrfs", NULL, fs_kobj);
	if (!btrfs_kset)
		return -ENOMEM;
812

813 814
	ret = btrfs_init_debugfs();
	if (ret)
815
		goto out1;
816

817
	init_feature_attrs();
818
	ret = sysfs_create_group(&btrfs_kset->kobj, &btrfs_feature_attr_group);
819 820 821 822 823 824 825 826
	if (ret)
		goto out2;

	return 0;
out2:
	debugfs_remove_recursive(btrfs_debugfs_root_dentry);
out1:
	kset_unregister(btrfs_kset);
827

828
	return ret;
829 830
}

C
Christoph Hellwig 已提交
831
void btrfs_exit_sysfs(void)
832
{
833
	sysfs_remove_group(&btrfs_kset->kobj, &btrfs_feature_attr_group);
834
	kset_unregister(btrfs_kset);
835
	debugfs_remove_recursive(btrfs_debugfs_root_dentry);
836
}
837