[PATCH 9/9] nilfs2: integrate sysfs support into driver

[Vyacheslav Dubeyko]

From: Vyacheslav Dubeyko <Vyacheslav.Dubeyko-***@public.gmane.org>
Subject: [PATCH 9/9] nilfs2: integrate sysfs support into driver

This patch integrates creation of sysfs groups and
attributes into NILFS file system driver.

Signed-off-by: Vyacheslav Dubeyko <Vyacheslav.Dubeyko-***@public.gmane.org>
CC: Vyacheslav Dubeyko <slava-***@public.gmane.org>
CC: Ryusuke Konishi <konishi.ryusuke-***@public.gmane.org>
---
fs/nilfs2/Makefile | 2 +-
fs/nilfs2/nilfs.h | 8 ++++++++
fs/nilfs2/super.c | 9 ++++++++-
fs/nilfs2/the_nilfs.c | 15 ++++++++++++++-
4 files changed, 31 insertions(+), 3 deletions(-)

diff --git a/fs/nilfs2/Makefile b/fs/nilfs2/Makefile
index 85c9873..fc603e0 100644
--- a/fs/nilfs2/Makefile
+++ b/fs/nilfs2/Makefile
@@ -2,4 +2,4 @@ obj-$(CONFIG_NILFS2_FS) += nilfs2.o
nilfs2-y := inode.o file.o dir.o super.o namei.o page.o mdt.o \
btnode.o bmap.o btree.o direct.o dat.o recovery.o \
the_nilfs.o segbuf.o segment.o cpfile.o sufile.o \
- ifile.o alloc.o gcinode.o ioctl.o
+ ifile.o alloc.o gcinode.o ioctl.o sysfs.o
diff --git a/fs/nilfs2/nilfs.h b/fs/nilfs2/nilfs.h
index 9bc72de..0696161 100644
--- a/fs/nilfs2/nilfs.h
+++ b/fs/nilfs2/nilfs.h
@@ -320,6 +320,14 @@ int nilfs_gccache_wait_and_mark_dirty(struct buffer_head *);
int nilfs_init_gcinode(struct inode *inode);
void nilfs_remove_all_gcinodes(struct the_nilfs *nilfs);

+/* sysfs.c */
+int __init nilfs_sysfs_init(void);
+void nilfs_sysfs_exit(void);
+int nilfs_sysfs_create_device_group(struct super_block *);
+void nilfs_sysfs_delete_device_group(struct the_nilfs *);
+int nilfs_sysfs_create_snapshot_group(struct nilfs_root *);
+void nilfs_sysfs_delete_snapshot_group(struct nilfs_root *);
+
/*
* Inodes and files operations
*/
diff --git a/fs/nilfs2/super.c b/fs/nilfs2/super.c
index 7ac2a12..4f72848 100644
--- a/fs/nilfs2/super.c
+++ b/fs/nilfs2/super.c
@@ -1451,13 +1451,19 @@ static int __init init_nilfs_fs(void)
if (err)
goto fail;

- err = register_filesystem(&nilfs_fs_type);
+ err = nilfs_sysfs_init();
if (err)
goto free_cachep;

+ err = register_filesystem(&nilfs_fs_type);
+ if (err)
+ goto deinit_sysfs_entry;
+
printk(KERN_INFO "NILFS version 2 loaded\n");
return 0;

+deinit_sysfs_entry:
+ nilfs_sysfs_exit();
free_cachep:
nilfs_destroy_cachep();
fail:
@@ -1467,6 +1473,7 @@ fail:
static void __exit exit_nilfs_fs(void)
{
nilfs_destroy_cachep();
+ nilfs_sysfs_exit();
unregister_filesystem(&nilfs_fs_type);
}

diff --git a/fs/nilfs2/the_nilfs.c b/fs/nilfs2/the_nilfs.c
index 475b8b9..cae1822 100644
--- a/fs/nilfs2/the_nilfs.c
+++ b/fs/nilfs2/the_nilfs.c
@@ -98,6 +98,7 @@ void destroy_nilfs(struct the_nilfs *nilfs)
{
might_sleep();
if (nilfs_init(nilfs)) {
+ nilfs_sysfs_delete_device_group(nilfs);
brelse(nilfs->ns_sbh[0]);
brelse(nilfs->ns_sbh[1]);
}
@@ -631,6 +632,10 @@ int init_nilfs(struct the_nilfs *nilfs, struct super_block *sb, char *data)
if (err)
goto failed_sbh;

+ err = nilfs_sysfs_create_device_group(sb);
+ if (err)
+ goto failed_sbh;
+
set_nilfs_init(nilfs);
err = 0;
out:
@@ -731,12 +736,13 @@ nilfs_find_or_create_root(struct the_nilfs *nilfs, __u64 cno)
{
struct rb_node **p, *parent;
struct nilfs_root *root, *new;
+ int err;

root = nilfs_lookup_root(nilfs, cno);
if (root)
return root;

- new = kmalloc(sizeof(*root), GFP_KERNEL);
+ new = kzalloc(sizeof(*root), GFP_KERNEL);
if (!new)
return NULL;

@@ -771,6 +777,12 @@ nilfs_find_or_create_root(struct the_nilfs *nilfs, __u64 cno)
rb_link_node(&new->rb_node, parent, p);
rb_insert_color(&new->rb_node, &nilfs->ns_cptree);

+ err = nilfs_sysfs_create_snapshot_group(new);
+ if (err) {
+ kfree(new);
+ new = NULL;
+ }
+
spin_unlock(&nilfs->ns_cptree_lock);

return new;
@@ -782,6 +794,7 @@ void nilfs_put_root(struct nilfs_root *root)
struct the_nilfs *nilfs = root->nilfs;

spin_lock(&nilfs->ns_cptree_lock);
+ nilfs_sysfs_delete_snapshot_group(root);
rb_erase(&root->rb_node, &nilfs->ns_cptree);
spin_unlock(&nilfs->ns_cptree_lock);
if (root->ifile)