From: Jeff Mahoney <jeffm@suse.com>
To: linux-btrfs@vger.kernel.org
Cc: dsterba@suse.cz, clmason@fusionio.com
Subject: [patch 4/9] btrfs: export supported featured to sysfs
Date: Mon, 16 Sep 2013 14:19:14 -0400 [thread overview]
Message-ID: <20130916182018.291611624@suse.com> (raw)
In-Reply-To: 20130916181910.799140428@suse.com
This patch adds the ability to publish supported features to sysfs under
/sys/fs/btrfs/features.
The files are module-wide and export which features the kernel supports.
The content, for now, is just "0\n".
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
---
fs/btrfs/ctree.h | 4 ++--
fs/btrfs/disk-io.c | 1 -
fs/btrfs/sysfs.c | 52 ++++++++++++++++++++++++++++++++++++++++++++++++++++
fs/btrfs/sysfs.h | 35 +++++++++++++++++++++++++++++++++++
4 files changed, 89 insertions(+), 3 deletions(-)
--- a/fs/btrfs/ctree.h 2013-09-16 13:46:30.875025162 -0400
+++ b/fs/btrfs/ctree.h 2013-09-16 13:48:53.252952421 -0400
@@ -32,6 +32,7 @@
#include <asm/kmap_types.h>
#include <linux/pagemap.h>
#include <linux/btrfs.h>
+#include <linux/kobj_completion.h>
#include "extent_io.h"
#include "extent_map.h"
#include "async-thread.h"
@@ -1511,8 +1512,7 @@ struct btrfs_fs_info {
struct task_struct *cleaner_kthread;
int thread_pool_size;
- struct kobject super_kobj;
- struct completion kobj_unregister;
+ struct kobj_completion super_kc;
int do_barriers;
int closing;
int log_root_recovering;
--- a/fs/btrfs/disk-io.c 2013-09-16 13:46:30.875025162 -0400
+++ b/fs/btrfs/disk-io.c 2013-09-16 13:46:32.970992936 -0400
@@ -2163,7 +2163,6 @@ int open_ctree(struct super_block *sb,
mutex_init(&fs_info->reloc_mutex);
seqlock_init(&fs_info->profiles_lock);
- init_completion(&fs_info->kobj_unregister);
INIT_LIST_HEAD(&fs_info->dirty_cowonly_roots);
INIT_LIST_HEAD(&fs_info->space_info);
INIT_LIST_HEAD(&fs_info->tree_mod_seq_list);
--- a/fs/btrfs/sysfs.c 2013-09-16 13:46:30.875025162 -0400
+++ b/fs/btrfs/sysfs.c 2013-09-16 13:48:53.252952421 -0400
@@ -22,24 +22,76 @@
#include <linux/completion.h>
#include <linux/buffer_head.h>
#include <linux/kobject.h>
+#include <linux/kobj_completion.h>
#include "ctree.h"
#include "disk-io.h"
#include "transaction.h"
+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(compress_lzov2, COMPRESS_LZOv2);
+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);
+
+static struct attribute *btrfs_supp_feature_attrs[] = {
+ BTRFS_FEAT_ATTR_LIST(mixed_backref)
+ BTRFS_FEAT_ATTR_LIST(default_subvol)
+ BTRFS_FEAT_ATTR_LIST(mixed_groups)
+ BTRFS_FEAT_ATTR_LIST(compress_lzo)
+ BTRFS_FEAT_ATTR_LIST(compress_lzov2)
+ BTRFS_FEAT_ATTR_LIST(big_metadata)
+ BTRFS_FEAT_ATTR_LIST(extended_iref)
+ BTRFS_FEAT_ATTR_LIST(raid56)
+ BTRFS_FEAT_ATTR_LIST(skinny_metadata)
+ NULL
+};
+
+static ssize_t btrfs_supp_attr_show(struct kobject *kobj, struct attribute *a,
+ char *buf)
+{
+ return snprintf(buf, PAGE_SIZE, "0\n");
+}
+
+static const struct sysfs_ops btrfs_supp_attr_ops = {
+ .show = btrfs_supp_attr_show,
+};
+
+static struct kobj_type btrfs_supp_feat_ktype = {
+ .default_attrs = btrfs_supp_feature_attrs,
+ .sysfs_ops = &btrfs_supp_attr_ops,
+ .release = kobj_completion_release,
+};
+
/* /sys/fs/btrfs/ entry */
static struct kset *btrfs_kset;
+static struct kobj_completion btrfs_features;
int btrfs_init_sysfs(void)
{
+ int ret;
btrfs_kset = kset_create_and_add("btrfs", NULL, fs_kobj);
if (!btrfs_kset)
return -ENOMEM;
+
+ kobj_completion_init(&btrfs_features, &btrfs_supp_feat_ktype);
+ btrfs_features.kc_kobj.kset = btrfs_kset;
+ ret = kobject_add(&btrfs_features.kc_kobj, NULL, "features");
+ if (ret) {
+ kset_unregister(btrfs_kset);
+ return ret;
+ }
+
return 0;
}
void btrfs_exit_sysfs(void)
{
+ kobj_completion_del_and_wait(&btrfs_features);
kset_unregister(btrfs_kset);
}
--- /dev/null 1970-01-01 00:00:00.000000000 +0000
+++ b/fs/btrfs/sysfs.h 2013-09-16 13:49:01.064844933 -0400
@@ -0,0 +1,35 @@
+#ifndef _BTRFS_SYSFS_H_
+#define _BTRFS_SYSFS_H_
+
+enum btrfs_feature_set {
+ FEAT_COMPAT,
+ FEAT_COMPAT_RO,
+ FEAT_INCOMPAT,
+ FEAT_MAX
+};
+
+struct btrfs_feature_attr {
+ struct attribute attr; /* global show, no store */
+ enum btrfs_feature_set feature_set;
+ u64 feature_bit;
+};
+
+#define BTRFS_FEAT_ATTR(_name, _feature_set, _prefix, _feature_bit) \
+static struct btrfs_feature_attr btrfs_attr_##_name = { \
+ .attr = { .name = __stringify(_name), .mode = S_IRUGO, }, \
+ .feature_set = _feature_set, \
+ .feature_bit = _prefix ##_## _feature_bit, \
+}
+#define BTRFS_FEAT_ATTR_LIST(_name) (&btrfs_attr_##_name.attr),
+
+#define BTRFS_FEAT_ATTR_COMPAT(name, feature) \
+ BTRFS_FEAT_ATTR(name, FEAT_COMPAT, BTRFS_FEATURE_COMPAT, feature)
+#define BTRFS_FEAT_ATTR_COMPAT_RO(name, feature) \
+ BTRFS_FEAT_ATTR(name, FEAT_COMPAT_RO, BTRFS_FEATURE_COMPAT, feature)
+#define BTRFS_FEAT_ATTR_INCOMPAT(name, feature) \
+ BTRFS_FEAT_ATTR(name, FEAT_INCOMPAT, BTRFS_FEATURE_INCOMPAT, feature)
+
+/* convert from attribute */
+#define to_btrfs_feature_attr(a) \
+ container_of(a, struct btrfs_feature_attr, attr)
+#endif /* _BTRFS_SYSFS_H_ */
next prev parent reply other threads:[~2013-09-16 18:22 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-09-16 18:19 [patch 0/9 v3] add ability to query/change feature bits online Jeff Mahoney
2013-09-16 18:19 ` [patch 1/9] btrfs: add ioctls " Jeff Mahoney
2013-09-18 14:05 ` David Sterba
2013-09-18 14:14 ` David Sterba
2013-09-18 14:29 ` Jeff Mahoney
2013-09-16 18:19 ` [patch 2/9] btrfs: use btrfs_commit_transaction when setting fslabel Jeff Mahoney
2013-09-16 18:19 ` [patch 3/9] kobject: introduce kobj_completion Jeff Mahoney
2013-09-16 18:19 ` Jeff Mahoney [this message]
2013-09-16 18:19 ` [patch 5/9] btrfs: add per-super attributes to sysfs Jeff Mahoney
2013-09-16 18:19 ` [patch 6/9] btrfs: publish per-super features " Jeff Mahoney
2013-09-16 18:19 ` [patch 7/9] btrfs: add publishing of unknown features in sysfs Jeff Mahoney
2013-09-16 18:19 ` [patch 8/9] btrfs: add ability to change features via sysfs Jeff Mahoney
2013-09-16 18:19 ` [patch 9/9] btrfs: use feature attribute names to print better error messages Jeff Mahoney
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