Commit 12574a9f authored by Amir Goldstein's avatar Amir Goldstein Committed by Miklos Szeredi
Browse files

ovl: consistent i_ino for non-samefs with xino 



When overlay layers are not all on the same fs, but all inode numbers
of underlying fs do not use the high 'xino' bits, overlay st_ino values
are constant and persistent.

In that case, set i_ino value to the same value as st_ino for nfsd
readdirplus validator.

Signed-off-by: default avatarAmir Goldstein <amir73il@gmail.com>
Signed-off-by: default avatarMiklos Szeredi <mszeredi@redhat.com>
parent e487d889

fs/overlayfs/export.c

+1 −1
Original line number Diff line number Diff line
@@ -305,7 +305,7 @@ static struct dentry *ovl_obtain_alias(struct super_block *sb, 
	if (d_is_dir(upper ?: lower))

		return ERR_PTR(-EIO);



	inode = ovl_get_inode(sb, dget(upper), lower, index, !!lower);

	inode = ovl_get_inode(sb, dget(upper), lowerpath, index, !!lower);

	if (IS_ERR(inode)) {

		dput(upper);

		return ERR_CAST(inode);

fs/overlayfs/inode.c

+18 −9
Original line number Diff line number Diff line
@@ -489,19 +489,26 @@ static inline void ovl_lockdep_annotate_inode_mutex_key(struct inode *inode) 
}



static void ovl_fill_inode(struct inode *inode, umode_t mode, dev_t rdev,

			   unsigned long ino)

			   unsigned long ino, int fsid)

{

	int xinobits = ovl_xino_bits(inode->i_sb);



	/*

	 * When NFS export is enabled and d_ino is consistent with st_ino

	 * (samefs), set the same value to i_ino, because nfsd readdirplus

	 * compares d_ino values to i_ino values of child entries. When called

	 * from ovl_new_inode(), ino arg is 0, so i_ino will be updated to real

	 * (samefs or i_ino has enough bits to encode layer), set the same

	 * value used for d_ino to i_ino, because nfsd readdirplus compares

	 * d_ino values to i_ino values of child entries. When called from

	 * ovl_new_inode(), ino arg is 0, so i_ino will be updated to real

	 * upper inode i_ino on ovl_inode_init() or ovl_inode_update().

	 */

	if (inode->i_sb->s_export_op && ovl_same_sb(inode->i_sb))

	if (inode->i_sb->s_export_op &&

	    (ovl_same_sb(inode->i_sb) || xinobits)) {

		inode->i_ino = ino;

	else

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

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

	} else {

		inode->i_ino = get_next_ino();

	}

	inode->i_mode = mode;

	inode->i_flags |= S_NOCMTIME;

#ifdef CONFIG_FS_POSIX_ACL
@@ -637,7 +644,7 @@ struct inode *ovl_new_inode(struct super_block *sb, umode_t mode, dev_t rdev) 


	inode = new_inode(sb);

	if (inode)

		ovl_fill_inode(inode, mode, rdev, 0);

		ovl_fill_inode(inode, mode, rdev, 0, 0);



	return inode;

}
@@ -743,12 +750,14 @@ static bool ovl_hash_bylower(struct super_block *sb, struct dentry *upper, 
}



struct inode *ovl_get_inode(struct super_block *sb, struct dentry *upperdentry,

			    struct dentry *lowerdentry, struct dentry *index,

			    struct ovl_path *lowerpath, struct dentry *index,

			    unsigned int numlower)

{

	struct inode *realinode = upperdentry ? d_inode(upperdentry) : NULL;

	struct inode *inode;

	struct dentry *lowerdentry = lowerpath ? lowerpath->dentry : NULL;

	bool bylower = ovl_hash_bylower(sb, upperdentry, lowerdentry, index);

	int fsid = bylower ? lowerpath->layer->fsid : 0;

	bool is_dir;

	unsigned long ino = 0;
@@ -796,7 +805,7 @@ struct inode *ovl_get_inode(struct super_block *sb, struct dentry *upperdentry, 
		if (!inode)

			goto out_nomem;

	}

	ovl_fill_inode(inode, realinode->i_mode, realinode->i_rdev, ino);

	ovl_fill_inode(inode, realinode->i_mode, realinode->i_rdev, ino, fsid);

	ovl_inode_init(inode, upperdentry, lowerdentry);



	if (upperdentry && ovl_is_impuredir(upperdentry))

fs/overlayfs/namei.c

+1 −3
Original line number Diff line number Diff line
@@ -1004,9 +1004,7 @@ struct dentry *ovl_lookup(struct inode *dir, struct dentry *dentry, 
		upperdentry = dget(index);



	if (upperdentry || ctr) {

		if (ctr)

			origin = stack[0].dentry;

		inode = ovl_get_inode(dentry->d_sb, upperdentry, origin, index,

		inode = ovl_get_inode(dentry->d_sb, upperdentry, stack, index,

				      ctr);

		err = PTR_ERR(inode);

		if (IS_ERR(inode))

fs/overlayfs/overlayfs.h

+1 −1
Original line number Diff line number Diff line
@@ -338,7 +338,7 @@ struct inode *ovl_new_inode(struct super_block *sb, umode_t mode, dev_t rdev); 
struct inode *ovl_lookup_inode(struct super_block *sb, struct dentry *real,

			       bool is_upper);

struct inode *ovl_get_inode(struct super_block *sb, struct dentry *upperdentry,

			    struct dentry *lowerdentry, struct dentry *index,

			    struct ovl_path *lowerpath, struct dentry *index,

			    unsigned int numlower);

static inline void ovl_copyattr(struct inode *from, struct inode *to)

{

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