Commit 0af950f5 authored by Amir Goldstein's avatar Amir Goldstein
Browse files

ovl: move ovl_entry into ovl_inode 



The lower stacks of all the ovl inode aliases should be identical
and there is redundant information in ovl_entry and ovl_inode.

Move lowerstack into ovl_inode and keep only the OVL_E_FLAGS
per overlay dentry.

Following patches will deduplicate redundant ovl_inode fields.

Note that for pure upper and negative dentries, OVL_E(dentry) may be
NULL now, so it is imporatnt to use the ovl_numlower() accessor.

Reviewed-by: default avatarAlexander Larsson <alexl@redhat.com>
Signed-off-by: default avatarAmir Goldstein <amir73il@gmail.com>
Signed-off-by: default avatarMiklos Szeredi <mszeredi@redhat.com>
parent 163db0da

fs/overlayfs/dir.c

+1 −1
Original line number Diff line number Diff line
@@ -269,7 +269,7 @@ static int ovl_instantiate(struct dentry *dentry, struct inode *inode, 


	ovl_dir_modified(dentry->d_parent, false);

	ovl_dentry_set_upper_alias(dentry);

	ovl_dentry_init_reval(dentry, newdentry);

	ovl_dentry_init_reval(dentry, newdentry, NULL);



	if (!hardlink) {

		/*

fs/overlayfs/export.c

+12 −10
Original line number Diff line number Diff line
@@ -286,7 +286,7 @@ static struct dentry *ovl_obtain_alias(struct super_block *sb, 
	struct dentry *lower = lowerpath ? lowerpath->dentry : NULL;

	struct dentry *upper = upper_alias ?: index;

	struct dentry *dentry;

	struct inode *inode;

	struct inode *inode = NULL;

	struct ovl_entry *oe;

	struct ovl_inode_params oip = {

		.lowerpath = lowerpath,
@@ -298,9 +298,19 @@ static struct dentry *ovl_obtain_alias(struct super_block *sb, 
	if (d_is_dir(upper ?: lower))

		return ERR_PTR(-EIO);



	oe = ovl_alloc_entry(!!lower);

	if (!oe)

		return ERR_PTR(-ENOMEM);



	oip.upperdentry = dget(upper);

	if (lower) {

		ovl_lowerstack(oe)->dentry = dget(lower);

		ovl_lowerstack(oe)->layer = lowerpath->layer;

	}

	oip.oe = oe;

	inode = ovl_get_inode(sb, &oip);

	if (IS_ERR(inode)) {

		ovl_free_entry(oe);

		dput(upper);

		return ERR_CAST(inode);

	}
@@ -315,19 +325,11 @@ static struct dentry *ovl_obtain_alias(struct super_block *sb, 
	dentry = d_alloc_anon(inode->i_sb);

	if (unlikely(!dentry))

		goto nomem;

	oe = ovl_alloc_entry(lower ? 1 : 0);

	if (!oe)

		goto nomem;



	if (lower) {

		ovl_lowerstack(oe)->dentry = dget(lower);

		ovl_lowerstack(oe)->layer = lowerpath->layer;

	}

	dentry->d_fsdata = oe;

	if (upper_alias)

		ovl_dentry_set_upper_alias(dentry);



	ovl_dentry_init_reval(dentry, upper);

	ovl_dentry_init_reval(dentry, upper, OVL_I_E(inode));



	return d_instantiate_anon(dentry, inode);

fs/overlayfs/inode.c

+4 −4
Original line number Diff line number Diff line
@@ -1002,8 +1002,9 @@ void ovl_inode_init(struct inode *inode, struct ovl_inode_params *oip, 
	struct inode *realinode;

	struct ovl_inode *oi = OVL_I(inode);



	if (oip->upperdentry)

	oi->__upperdentry = oip->upperdentry;

	oi->oe = oip->oe;

	oi->redirect = oip->redirect;

	if (oip->lowerpath && oip->lowerpath->dentry) {

		oi->lowerpath.dentry = dget(oip->lowerpath->dentry);

		oi->lowerpath.layer = oip->lowerpath->layer;
@@ -1368,6 +1369,7 @@ struct inode *ovl_get_inode(struct super_block *sb, 
			}



			dput(upperdentry);

			ovl_free_entry(oip->oe);

			kfree(oip->redirect);

			goto out;

		}
@@ -1397,8 +1399,6 @@ struct inode *ovl_get_inode(struct super_block *sb, 
	if (oip->index)

		ovl_set_flag(OVL_INDEX, inode);



	OVL_I(inode)->redirect = oip->redirect;



	if (bylower)

		ovl_set_flag(OVL_CONST_INO, inode);

fs/overlayfs/namei.c

+10 −9
Original line number Diff line number Diff line
@@ -831,7 +831,7 @@ static int ovl_fix_origin(struct ovl_fs *ofs, struct dentry *dentry, 
struct dentry *ovl_lookup(struct inode *dir, struct dentry *dentry,

			  unsigned int flags)

{

	struct ovl_entry *oe;

	struct ovl_entry *oe = NULL;

	const struct cred *old_cred;

	struct ovl_fs *ofs = dentry->d_sb->s_fs_info;

	struct ovl_entry *poe = OVL_E(dentry->d_parent);
@@ -1067,13 +1067,14 @@ struct dentry *ovl_lookup(struct inode *dir, struct dentry *dentry, 
		}

	}



	if (ctr) {

		oe = ovl_alloc_entry(ctr);

		err = -ENOMEM;

		if (!oe)

			goto out_put;



		ovl_stack_cpy(ovl_lowerstack(oe), stack, ctr);

	dentry->d_fsdata = oe;

	}



	if (upperopaque)

		ovl_dentry_set_opaque(dentry);
@@ -1107,6 +1108,7 @@ struct dentry *ovl_lookup(struct inode *dir, struct dentry *dentry, 
		struct ovl_inode_params oip = {

			.upperdentry = upperdentry,

			.lowerpath = stack,

			.oe = oe,

			.index = index,

			.numlower = ctr,

			.redirect = upperredirect,
@@ -1122,7 +1124,7 @@ struct dentry *ovl_lookup(struct inode *dir, struct dentry *dentry, 
			ovl_set_flag(OVL_UPPERDATA, inode);

	}



	ovl_dentry_init_reval(dentry, upperdentry);

	ovl_dentry_init_reval(dentry, upperdentry, OVL_I_E(inode));



	revert_creds(old_cred);

	if (origin_path) {
@@ -1135,7 +1137,6 @@ struct dentry *ovl_lookup(struct inode *dir, struct dentry *dentry, 
	return d_splice_alias(inode, dentry);



out_free_oe:

	dentry->d_fsdata = NULL;

	ovl_free_entry(oe);

out_put:

	dput(index);

fs/overlayfs/overlayfs.h

+4 −2
Original line number Diff line number Diff line
@@ -381,9 +381,10 @@ struct ovl_entry *ovl_alloc_entry(unsigned int numlower); 
void ovl_free_entry(struct ovl_entry *oe);

bool ovl_dentry_remote(struct dentry *dentry);

void ovl_dentry_update_reval(struct dentry *dentry, struct dentry *realdentry);

void ovl_dentry_init_reval(struct dentry *dentry, struct dentry *upperdentry);

void ovl_dentry_init_reval(struct dentry *dentry, struct dentry *upperdentry,

			   struct ovl_entry *oe);

void ovl_dentry_init_flags(struct dentry *dentry, struct dentry *upperdentry,

			   unsigned int mask);

			   struct ovl_entry *oe, unsigned int mask);

bool ovl_dentry_weird(struct dentry *dentry);

enum ovl_path_type ovl_path_type(struct dentry *dentry);

void ovl_path_upper(struct dentry *dentry, struct path *path);
@@ -653,6 +654,7 @@ struct ovl_inode_params { 
	struct inode *newinode;

	struct dentry *upperdentry;

	struct ovl_path *lowerpath;

	struct ovl_entry *oe;

	bool index;

	unsigned int numlower;

	char *redirect;