From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from cantor2.suse.de ([195.135.220.15]:51724 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751945Ab3IPSWR (ORCPT ); Mon, 16 Sep 2013 14:22:17 -0400 Message-Id: <20130916182018.459541510@suse.com> Date: Mon, 16 Sep 2013 14:19:15 -0400 From: Jeff Mahoney To: linux-btrfs@vger.kernel.org Cc: dsterba@suse.cz, clmason@fusionio.com Subject: [patch 5/9] btrfs: add per-super attributes to sysfs References: <20130916181910.799140428@suse.com> Sender: linux-btrfs-owner@vger.kernel.org List-ID: This patch adds per-super attributes to sysfs. It doesn't publish any attributes yet, but does the proper lifetime handling as well as the basic infrastructure to add new attributes. Signed-off-by: Jeff Mahoney --- fs/btrfs/ctree.h | 2 + fs/btrfs/super.c | 13 +++++++++++- fs/btrfs/sysfs.c | 56 +++++++++++++++++++++++++++++++++++++++++++++++++++++++ fs/btrfs/sysfs.h | 20 +++++++++++++++++++ 4 files changed, 90 insertions(+), 1 deletion(-) --- a/fs/btrfs/ctree.h 2013-09-16 13:49:06.656768298 -0400 +++ b/fs/btrfs/ctree.h 2013-09-16 13:49:25.464512784 -0400 @@ -3694,6 +3694,8 @@ int btrfs_defrag_leaves(struct btrfs_tra /* sysfs.c */ int btrfs_init_sysfs(void); void btrfs_exit_sysfs(void); +int btrfs_sysfs_add_one(struct btrfs_fs_info *fs_info); +void btrfs_sysfs_remove_one(struct btrfs_fs_info *fs_info); /* xattr.c */ ssize_t btrfs_listxattr(struct dentry *dentry, char *buffer, size_t size); --- a/fs/btrfs/super.c 2013-09-16 13:49:06.660768245 -0400 +++ b/fs/btrfs/super.c 2013-09-16 13:49:25.464512784 -0400 @@ -301,6 +301,8 @@ void __btrfs_panic(struct btrfs_fs_info static void btrfs_put_super(struct super_block *sb) { + btrfs_sysfs_remove_one(btrfs_sb(sb)); + (void)close_ctree(btrfs_sb(sb)->tree_root); /* FIXME: need to fix VFS to return error? */ /* AV: return it _where_? ->put_super() can be triggered by any number @@ -1143,8 +1145,17 @@ static struct dentry *btrfs_mount(struct } root = !error ? get_default_root(s, subvol_objectid) : ERR_PTR(error); - if (IS_ERR(root)) + if (IS_ERR(root)) { deactivate_locked_super(s); + return root; + } + + error = btrfs_sysfs_add_one(fs_info); + if (error) { + dput(root); + deactivate_locked_super(s); + return ERR_PTR(error); + } return root; --- a/fs/btrfs/sysfs.c 2013-09-16 13:49:06.668768135 -0400 +++ b/fs/btrfs/sysfs.c 2013-09-16 13:49:25.464512784 -0400 @@ -27,6 +27,7 @@ #include "ctree.h" #include "disk-io.h" #include "transaction.h" +#include "sysfs.h" BTRFS_FEAT_ATTR_INCOMPAT(mixed_backref, MIXED_BACKREF); BTRFS_FEAT_ATTR_INCOMPAT(default_subvol, DEFAULT_SUBVOL); @@ -67,8 +68,63 @@ static struct kobj_type btrfs_supp_feat_ .release = kobj_completion_release, }; +static struct attribute *btrfs_attrs[] = { + NULL, +}; + +#define super_kobj_to_fs_info(kobj) \ + container_of(kobj, struct btrfs_fs_info, super_kc.kc_kobj) + +static ssize_t btrfs_attr_show(struct kobject *kobj, + struct attribute *attr, char *buf) +{ + struct btrfs_attr *a = container_of(attr, struct btrfs_attr, attr); + struct btrfs_fs_info *fs_info = super_kobj_to_fs_info(kobj); + + return a->show ? a->show(a, fs_info, buf) : 0; +} + +static ssize_t btrfs_attr_store(struct kobject *kobj, + struct attribute *attr, + const char *buf, size_t len) +{ + struct btrfs_attr *a = container_of(attr, struct btrfs_attr, attr); + struct btrfs_fs_info *fs_info = super_kobj_to_fs_info(kobj); + + return a->store ? a->store(a, fs_info, buf, len) : 0; +} + +static const struct sysfs_ops btrfs_attr_ops = { + .show = btrfs_attr_show, + .store = btrfs_attr_store, +}; + +static struct kobj_type btrfs_ktype = { + .default_attrs = btrfs_attrs, + .sysfs_ops = &btrfs_attr_ops, + .release = kobj_completion_release, +}; + /* /sys/fs/btrfs/ entry */ static struct kset *btrfs_kset; + +int btrfs_sysfs_add_one(struct btrfs_fs_info *fs_info) +{ + int error; + + kobj_completion_init(&fs_info->super_kc, &btrfs_ktype); + fs_info->super_kc.kc_kobj.kset = btrfs_kset; + error = kobject_add(&fs_info->super_kc.kc_kobj, NULL, + "%pU", fs_info->fsid); + + return error; +} + +void btrfs_sysfs_remove_one(struct btrfs_fs_info *fs_info) +{ + kobj_completion_del_and_wait(&fs_info->super_kc); +} + static struct kobj_completion btrfs_features; int btrfs_init_sysfs(void) --- a/fs/btrfs/sysfs.h 2013-09-16 13:49:06.668768135 -0400 +++ b/fs/btrfs/sysfs.h 2013-09-16 13:49:25.464512784 -0400 @@ -8,6 +8,25 @@ enum btrfs_feature_set { FEAT_MAX }; +struct btrfs_attr { + struct attribute attr; + ssize_t (*show)(struct btrfs_attr *, struct btrfs_fs_info *, char *); + ssize_t (*store)(struct btrfs_attr *, struct btrfs_fs_info *, + const char *, size_t); +}; + +#define __INIT_BTRFS_ATTR(_name, _mode, _show, _store) \ +{ \ + .attr = { .name = __stringify(_name), .mode = _mode }, \ + .show = _show, \ + .store = _store, \ +} + +#define BTRFS_ATTR(_name, _mode, _show, _store) \ +static struct btrfs_attr btrfs_attr_##_name = \ + __INIT_BTRFS_ATTR(_name, _mode, _show, _store) +#define BTRFS_ATTR_LIST(_name) (&btrfs_attr_##_name.attr), + struct btrfs_feature_attr { struct attribute attr; /* global show, no store */ enum btrfs_feature_set feature_set; @@ -30,6 +49,7 @@ static struct btrfs_feature_attr btrfs_a BTRFS_FEAT_ATTR(name, FEAT_INCOMPAT, BTRFS_FEATURE_INCOMPAT, feature) /* convert from attribute */ +#define to_btrfs_attr(a) container_of(a, struct btrfs_attr, attr) #define to_btrfs_feature_attr(a) \ container_of(a, struct btrfs_feature_attr, attr) #endif /* _BTRFS_SYSFS_H_ */