Commit 26dbc60f authored by Eric W. Biederman's avatar Eric W. Biederman
Browse files

proc: Generalize proc_sys_prune_dcache into proc_prune_siblings_dcache 



This prepares the way for allowing the pid part of proc to use this
dcache pruning code as well.

Signed-off-by: default avatarEric W. Biederman <ebiederm@xmission.com>
parent 0afa5ca8

fs/proc/inode.c

+38 −0
Original line number Diff line number Diff line
@@ -103,6 +103,44 @@ void __init proc_init_kmemcache(void) 
	BUILD_BUG_ON(sizeof(struct proc_dir_entry) >= SIZEOF_PDE);

}



void proc_prune_siblings_dcache(struct hlist_head *inodes, spinlock_t *lock)

{

	struct inode *inode;

	struct proc_inode *ei;

	struct hlist_node *node;

	struct super_block *sb;



	rcu_read_lock();

	for (;;) {

		node = hlist_first_rcu(inodes);

		if (!node)

			break;

		ei = hlist_entry(node, struct proc_inode, sibling_inodes);

		spin_lock(lock);

		hlist_del_init_rcu(&ei->sibling_inodes);

		spin_unlock(lock);



		inode = &ei->vfs_inode;

		sb = inode->i_sb;

		if (!atomic_inc_not_zero(&sb->s_active))

			continue;

		inode = igrab(inode);

		rcu_read_unlock();

		if (unlikely(!inode)) {

			deactivate_super(sb);

			rcu_read_lock();

			continue;

		}



		d_prune_aliases(inode);

		iput(inode);

		deactivate_super(sb);



		rcu_read_lock();

	}

	rcu_read_unlock();

}



static int proc_show_options(struct seq_file *seq, struct dentry *root)

{

	struct super_block *sb = root->d_sb;

fs/proc/internal.h

+1 −0
Original line number Diff line number Diff line
@@ -210,6 +210,7 @@ extern const struct inode_operations proc_pid_link_inode_operations; 
extern const struct super_operations proc_sops;



void proc_init_kmemcache(void);

void proc_prune_siblings_dcache(struct hlist_head *inodes, spinlock_t *lock);

void set_proc_pid_nlink(void);

extern struct inode *proc_get_inode(struct super_block *, struct proc_dir_entry *);

extern void proc_entry_rundown(struct proc_dir_entry *);

fs/proc/proc_sysctl.c

+1 −34
Original line number Diff line number Diff line
@@ -269,40 +269,7 @@ static void unuse_table(struct ctl_table_header *p) 


static void proc_sys_prune_dcache(struct ctl_table_header *head)

{

	struct inode *inode;

	struct proc_inode *ei;

	struct hlist_node *node;

	struct super_block *sb;



	rcu_read_lock();

	for (;;) {

		node = hlist_first_rcu(&head->inodes);

		if (!node)

			break;

		ei = hlist_entry(node, struct proc_inode, sibling_inodes);

		spin_lock(&sysctl_lock);

		hlist_del_init_rcu(&ei->sibling_inodes);

		spin_unlock(&sysctl_lock);



		inode = &ei->vfs_inode;

		sb = inode->i_sb;

		if (!atomic_inc_not_zero(&sb->s_active))

			continue;

		inode = igrab(inode);

		rcu_read_unlock();

		if (unlikely(!inode)) {

			deactivate_super(sb);

			rcu_read_lock();

			continue;

		}



		d_prune_aliases(inode);

		iput(inode);

		deactivate_super(sb);



		rcu_read_lock();

	}

	rcu_read_unlock();

	proc_prune_siblings_dcache(&head->inodes, &sysctl_lock);

}



/* called under sysctl_lock, will reacquire if has to wait */