initial commit some aufs objects have a corresponding entry under sysfs, so the lifetime will be managed by struct kref even if CONFIG_SYSFS is disabled. This file is compiled unconditionally. Signed-off-by: J. R. Okajima <hooanon05@xxxxxxxxxxx> --- Documentation/ABI/testing/sysfs-aufs | 25 ++++++++ fs/aufs/sysaufs.c | 95 +++++++++++++++++++++++++++++ fs/aufs/sysaufs.h | 109 ++++++++++++++++++++++++++++++++++ 3 files changed, 229 insertions(+), 0 deletions(-) create mode 100644 Documentation/ABI/testing/sysfs-aufs create mode 100644 fs/aufs/sysaufs.c create mode 100644 fs/aufs/sysaufs.h diff --git a/Documentation/ABI/testing/sysfs-aufs b/Documentation/ABI/testing/sysfs-aufs new file mode 100644 index 0000000..ca49330 --- /dev/null +++ b/Documentation/ABI/testing/sysfs-aufs @@ -0,0 +1,25 @@ +What: /sys/fs/aufs/si_<id>/ +Date: March 2009 +Contact: J. R. Okajima <hooanon05@xxxxxxxxxxx> +Description: + Under /sys/fs/aufs, a directory named si_<id> is created + per aufs mount, where <id> is a unique id generated + internally. + +What: /sys/fs/aufs/si_<id>/br0, br1 ... brN +Date: March 2009 +Contact: J. R. Okajima <hooanon05@xxxxxxxxxxx> +Description: + It shows the abolute path of a member directory (which + is called branch) in aufs, and its permission. + +What: /sys/fs/aufs/si_<id>/xi_path +Date: March 2009 +Contact: J. R. Okajima <hooanon05@xxxxxxxxxxx> +Description: + It shows the abolute path of XINO (External Inode Number + Bitmap, Translation Table and Generation Table) file + even if it is the default path. + When the aufs mount option 'noxino' is specified, it + will be empty. About XINO files, see + Documentation/filesystems/aufs/aufs.5 in detail. diff --git a/fs/aufs/sysaufs.c b/fs/aufs/sysaufs.c new file mode 100644 index 0000000..623f2e6 --- /dev/null +++ b/fs/aufs/sysaufs.c @@ -0,0 +1,95 @@ +/* + * Copyright (C) 2005-2009 Junjiro R. Okajima + * + * This program, aufs is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + */ + +/* + * sysfs interface and lifetime management + * they are necessary regardless sysfs is disabled. + */ + +#include <linux/fs.h> +#include <linux/random.h> +#include <linux/sysfs.h> +#include "aufs.h" + +unsigned long sysaufs_si_mask; +struct kset *sysaufs_ket; + +#define AuSiAttr(_name) { \ + .attr = { .name = __stringify(_name), .mode = 0444 }, \ + .show = sysaufs_si_##_name, \ +} + +static struct sysaufs_si_attr sysaufs_si_attr_xi_path = AuSiAttr(xi_path); +struct attribute *sysaufs_si_attrs[] = { + &sysaufs_si_attr_xi_path.attr, + NULL, +}; + +static struct sysfs_ops au_sbi_ops = { + .show = sysaufs_si_show +}; + +static struct kobj_type au_sbi_ktype = { + .release = au_si_free, + .sysfs_ops = &au_sbi_ops, + .default_attrs = sysaufs_si_attrs +}; + +/* ---------------------------------------------------------------------- */ + +int sysaufs_si_init(struct au_sbinfo *sbinfo) +{ + int err; + + sbinfo->si_kobj.kset = sysaufs_ket; + /* cf. sysaufs_name() */ + err = kobject_init_and_add + (&sbinfo->si_kobj, &au_sbi_ktype, /*&sysaufs_ket->kobj*/NULL, + SysaufsSiNamePrefix "%lx", sysaufs_si_id(sbinfo)); + + dbgaufs_si_null(sbinfo); + if (!err) { + err = dbgaufs_si_init(sbinfo); + if (unlikely(err)) + kobject_put(&sbinfo->si_kobj); + } + return err; +} + +void sysaufs_fin(void) +{ + dbgaufs_fin(); + sysfs_remove_group(&sysaufs_ket->kobj, sysaufs_attr_group); + kset_unregister(sysaufs_ket); +} + +int __init sysaufs_init(void) +{ + int err; + + do { + get_random_bytes(&sysaufs_si_mask, sizeof(sysaufs_si_mask)); + } while (!sysaufs_si_mask); + + sysaufs_ket = kset_create_and_add(AUFS_NAME, NULL, fs_kobj); + err = PTR_ERR(sysaufs_ket); + if (IS_ERR(sysaufs_ket)) + goto out; + err = sysfs_create_group(&sysaufs_ket->kobj, sysaufs_attr_group); + if (unlikely(err)) { + kset_unregister(sysaufs_ket); + goto out; + } + + err = dbgaufs_init(); + if (unlikely(err)) + sysaufs_fin(); + out: + return err; +} diff --git a/fs/aufs/sysaufs.h b/fs/aufs/sysaufs.h new file mode 100644 index 0000000..c1202fa --- /dev/null +++ b/fs/aufs/sysaufs.h @@ -0,0 +1,109 @@ +/* + * Copyright (C) 2005-2009 Junjiro R. Okajima + * + * This program, aufs is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + */ + +/* + * sysfs interface and mount lifetime management + */ + +#ifndef __SYSAUFS_H__ +#define __SYSAUFS_H__ + +#ifdef __KERNEL__ + +#include <linux/fs.h> +#include <linux/sysfs.h> +#include <linux/aufs_type.h> +#include "module.h" + +struct sysaufs_si_attr { + struct attribute attr; + int (*show)(struct seq_file *seq, struct super_block *sb); +}; + +/* ---------------------------------------------------------------------- */ + +/* sysaufs.c */ +extern unsigned long sysaufs_si_mask; +extern struct kset *sysaufs_ket; +extern struct attribute *sysaufs_si_attrs[]; +int sysaufs_si_init(struct au_sbinfo *sbinfo); +int __init sysaufs_init(void); +void sysaufs_fin(void); + +/* ---------------------------------------------------------------------- */ + +/* some people doesn't like to show a pointer in kernel */ +static inline unsigned long sysaufs_si_id(struct au_sbinfo *sbinfo) +{ + return sysaufs_si_mask ^ (unsigned long)sbinfo; +} + +#define SysaufsSiNamePrefix "si_" +#define SysaufsSiNameLen (sizeof(SysaufsSiNamePrefix) + 16) +static inline void sysaufs_name(struct au_sbinfo *sbinfo, char *name) +{ + snprintf(name, SysaufsSiNameLen, SysaufsSiNamePrefix "%lx", + sysaufs_si_id(sbinfo)); +} + +struct au_branch; +#ifdef CONFIG_SYSFS +/* sysfs.c */ +extern struct attribute_group *sysaufs_attr_group; + +int sysaufs_si_xi_path(struct seq_file *seq, struct super_block *sb); +ssize_t sysaufs_si_show(struct kobject *kobj, struct attribute *attr, + char *buf); + +void sysaufs_br_init(struct au_branch *br); +void sysaufs_brs_add(struct super_block *sb, aufs_bindex_t bindex); +void sysaufs_brs_del(struct super_block *sb, aufs_bindex_t bindex); + +#define sysaufs_brs_init() do {} while (0) + +#else +#define sysaufs_attr_group NULL + +static inline +int sysaufs_si_xi_path(struct seq_file *seq, struct super_block *sb) +{ + return 0; +} + +static inline +ssize_t sysaufs_si_show(struct kobject *kobj, struct attribute *attr, + char *buf) +{ + return 0; +} + +static inline void sysaufs_br_init(struct au_branch *br) +{ + /* empty */ +} + +static inline void sysaufs_brs_add(struct super_block *sb, aufs_bindex_t bindex) +{ + /* nothing */ +} + +static inline void sysaufs_brs_del(struct super_block *sb, aufs_bindex_t bindex) +{ + /* nothing */ +} + +static inline void sysaufs_brs_init(void) +{ + sysaufs_brs = 0; +} + +#endif /* CONFIG_SYSFS */ + +#endif /* __KERNEL__ */ +#endif /* __SYSAUFS_H__ */ -- 1.6.1.284.g5dc13 -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html