[PATCH 03/58] staging/lustre/llite: Preparation to move /proc/fs/lustre/llite to sysfs

[green at linuxhacker.ru]

From: Oleg Drokin <green at linuxhacker.ru>

Add necessary infrastructure, add support for mountpoint
registration in /proc/fs/lustre/llite

Signed-off-by: Oleg Drokin <green at linuxhacker.ru>
---
 .../staging/lustre/lustre/llite/llite_internal.h   |  4 ++++
 drivers/staging/lustre/lustre/llite/llite_lib.c    |  7 ++++--
 drivers/staging/lustre/lustre/llite/lproc_llite.c  | 26 ++++++++++++++++++++++
 drivers/staging/lustre/lustre/llite/super25.c      | 11 ++++++++-
 4 files changed, 45 insertions(+), 3 deletions(-)

diff --git a/drivers/staging/lustre/lustre/llite/llite_internal.h b/drivers/staging/lustre/lustre/llite/llite_internal.h
index 1253b3c..5df2754 100644
--- a/drivers/staging/lustre/lustre/llite/llite_internal.h
+++ b/drivers/staging/lustre/lustre/llite/llite_internal.h
@@ -524,6 +524,9 @@ struct ll_sb_info {
 	struct rmtacl_ctl_table   ll_rct;
 	struct eacl_table	 ll_et;
 	__kernel_fsid_t		  ll_fsid;
+	struct kobject		 ll_kobj; /* sysfs object */
+	struct super_block	*ll_sb; /* struct super_block (for sysfs code)*/
+	struct completion	 ll_kobj_unregister;
 };
 
 #define LL_DEFAULT_MAX_RW_CHUNK      (32 * 1024 * 1024)
@@ -645,6 +648,7 @@ struct lov_stripe_md;
 extern spinlock_t inode_lock;
 
 extern struct proc_dir_entry *proc_lustre_fs_root;
+extern struct kset *llite_kset;
 
 static inline struct inode *ll_info2i(struct ll_inode_info *lli)
 {
diff --git a/drivers/staging/lustre/lustre/llite/llite_lib.c b/drivers/staging/lustre/lustre/llite/llite_lib.c
index 61acc70..53d427f 100644
--- a/drivers/staging/lustre/lustre/llite/llite_lib.c
+++ b/drivers/staging/lustre/lustre/llite/llite_lib.c
@@ -58,6 +58,7 @@
 
 struct kmem_cache *ll_file_data_slab;
 struct proc_dir_entry *proc_lustre_fs_root;
+struct kset *llite_kset;
 
 static LIST_HEAD(ll_super_blocks);
 static DEFINE_SPINLOCK(ll_sb_lock);
@@ -66,7 +67,7 @@ static DEFINE_SPINLOCK(ll_sb_lock);
 #define log2(n) ffz(~(n))
 #endif
 
-static struct ll_sb_info *ll_init_sbi(void)
+static struct ll_sb_info *ll_init_sbi(struct super_block *sb)
 {
 	struct ll_sb_info *sbi = NULL;
 	unsigned long pages;
@@ -134,6 +135,8 @@ static struct ll_sb_info *ll_init_sbi(void)
 	atomic_set(&sbi->ll_agl_total, 0);
 	sbi->ll_flags |= LL_SBI_AGL_ENABLED;
 
+	sbi->ll_sb = sb;
+
 	return sbi;
 }
 
@@ -915,7 +918,7 @@ int ll_fill_super(struct super_block *sb, struct vfsmount *mnt)
 	try_module_get(THIS_MODULE);
 
 	/* client additional sb info */
-	lsi->lsi_llsbi = sbi = ll_init_sbi();
+	lsi->lsi_llsbi = sbi = ll_init_sbi(sb);
 	if (!sbi) {
 		module_put(THIS_MODULE);
 		kfree(cfg);
diff --git a/drivers/staging/lustre/lustre/llite/lproc_llite.c b/drivers/staging/lustre/lustre/llite/lproc_llite.c
index 83a9b85..a3ecb61 100644
--- a/drivers/staging/lustre/lustre/llite/lproc_llite.c
+++ b/drivers/staging/lustre/lustre/llite/lproc_llite.c
@@ -872,6 +872,23 @@ static struct lprocfs_vars lprocfs_llite_obd_vars[] = {
 
 #define MAX_STRING_SIZE 128
 
+static struct attribute *llite_attrs[] = {
+	NULL,
+};
+
+static void llite_sb_release(struct kobject *kobj)
+{
+	struct ll_sb_info *sbi = container_of(kobj, struct ll_sb_info,
+					      ll_kobj);
+	complete(&sbi->ll_kobj_unregister);
+}
+
+static struct kobj_type llite_ktype = {
+	.default_attrs	= llite_attrs,
+	.sysfs_ops	= &lustre_sysfs_ops,
+	.release	= llite_sb_release,
+};
+
 static const struct llite_file_opcode {
 	__u32       opcode;
 	__u32       type;
@@ -1064,6 +1081,13 @@ int lprocfs_register_mountpoint(struct proc_dir_entry *parent,
 	if (err)
 		goto out;
 
+	sbi->ll_kobj.kset = llite_kset;
+	init_completion(&sbi->ll_kobj_unregister);
+	err = kobject_init_and_add(&sbi->ll_kobj, &llite_ktype, NULL,
+				   "%s", name);
+	if (err)
+		goto out;
+
 	/* MDC info */
 	obd = class_name2obd(mdc);
 
@@ -1124,6 +1148,8 @@ void lprocfs_unregister_mountpoint(struct ll_sb_info *sbi)
 {
 	if (sbi->ll_proc_root) {
 		lprocfs_remove(&sbi->ll_proc_root);
+		kobject_put(&sbi->ll_kobj);
+		wait_for_completion(&sbi->ll_kobj_unregister);
 		lprocfs_free_stats(&sbi->ll_ra_stats);
 		lprocfs_free_stats(&sbi->ll_stats);
 	}
diff --git a/drivers/staging/lustre/lustre/llite/super25.c b/drivers/staging/lustre/lustre/llite/super25.c
index a494f62..8753560 100644
--- a/drivers/staging/lustre/lustre/llite/super25.c
+++ b/drivers/staging/lustre/lustre/llite/super25.c
@@ -138,6 +138,12 @@ static int __init init_lustre_lite(void)
 
 	proc_lustre_fs_root = entry;
 
+	llite_kset = kset_create_and_add("llite", NULL, lustre_kobj);
+	if (!llite_kset) {
+		rc = -ENOMEM;
+		goto out_proc;
+	}
+
 	cfs_get_random_bytes(seed, sizeof(seed));
 
 	/* Nodes with small feet have little entropy. The NID for this
@@ -155,7 +161,7 @@ static int __init init_lustre_lite(void)
 	setup_timer(&ll_capa_timer, ll_capa_timer_callback, 0);
 	rc = ll_capa_thread_start();
 	if (rc != 0)
-		goto out_proc;
+		goto out_sysfs;
 
 	rc = vvp_global_init();
 	if (rc != 0)
@@ -176,6 +182,8 @@ out_vvp:
 out_capa:
 	del_timer(&ll_capa_timer);
 	ll_capa_thread_stop();
+out_sysfs:
+	kset_unregister(llite_kset);
 out_proc:
 	lprocfs_remove(&proc_lustre_fs_root);
 out_cache:
@@ -201,6 +209,7 @@ static void __exit exit_lustre_lite(void)
 	lustre_register_client_process_config(NULL);
 
 	lprocfs_remove(&proc_lustre_fs_root);
+	kset_unregister(llite_kset);
 
 	ll_xattr_fini();
 	vvp_global_fini();
-- 
2.1.0