Commit 4d314f78 authored by Amir Goldstein's avatar Amir Goldstein Committed by Miklos Szeredi
Browse files

ovl: use a private non-persistent ino pool 



There is no reason to deplete the system's global get_next_ino() pool for
overlay non-persistent inode numbers and there is no reason at all to
allocate non-persistent inode numbers for non-directories.

For non-directories, it is much better to leave i_ino the same as real
i_ino, to be consistent with st_ino/d_ino.

Signed-off-by: default avatarAmir Goldstein <amir73il@gmail.com>
Signed-off-by: default avatarMiklos Szeredi <mszeredi@redhat.com>
parent 83552eac

fs/overlayfs/inode.c

+12 −3
Original line number Diff line number Diff line
@@ -561,6 +561,15 @@ static inline void ovl_lockdep_annotate_inode_mutex_key(struct inode *inode) 
#endif

}



static void ovl_next_ino(struct inode *inode)

{

	struct ovl_fs *ofs = inode->i_sb->s_fs_info;



	inode->i_ino = atomic_long_inc_return(&ofs->last_ino);

	if (unlikely(!inode->i_ino))

		inode->i_ino = atomic_long_inc_return(&ofs->last_ino);

}



static void ovl_map_ino(struct inode *inode, unsigned long ino, int fsid)

{

	int xinobits = ovl_xino_bits(inode->i_sb);
@@ -572,12 +581,12 @@ static void ovl_map_ino(struct inode *inode, unsigned long ino, int fsid) 
	 * consistent with d_ino and st_ino values. An i_ino value inconsistent

	 * with d_ino also causes nfsd readdirplus to fail.

	 */

	if (ovl_same_dev(inode->i_sb)) {

	inode->i_ino = ino;

	if (ovl_same_dev(inode->i_sb)) {

		if (xinobits && fsid && !(ino >> (64 - xinobits)))

			inode->i_ino |= (unsigned long)fsid << (64 - xinobits);

	} else {

		inode->i_ino = get_next_ino();

	} else if (S_ISDIR(inode->i_mode)) {

		ovl_next_ino(inode);

	}

}

fs/overlayfs/ovl_entry.h

+2 −0
Original line number Diff line number Diff line
@@ -75,6 +75,8 @@ struct ovl_fs { 
	struct inode *indexdir_trap;

	/* -1: disabled, 0: same fs, 1..32: number of unused ino bits */

	int xino_mode;

	/* For allocation of non-persistent inode numbers */

	atomic_long_t last_ino;

};



static inline struct ovl_fs *OVL_FS(struct super_block *sb)

fs/overlayfs/super.c

+1 −0
Original line number Diff line number Diff line
@@ -1736,6 +1736,7 @@ static int ovl_fill_super(struct super_block *sb, void *data, int silent) 


	sb->s_stack_depth = 0;

	sb->s_maxbytes = MAX_LFS_FILESIZE;

	atomic_long_set(&ofs->last_ino, 1);

	/* Assume underlaying fs uses 32bit inodes unless proven otherwise */

	if (ofs->config.xino != OVL_XINO_OFF) {

		ofs->xino_mode = BITS_PER_LONG - 32;

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