Commit 495e6429 authored by Miklos Szeredi's avatar Miklos Szeredi
Browse files

vfs: add flags to d_real() 



Add a separate flags argument (in addition to the open flags) to control
the behavior of d_real().

Signed-off-by: default avatarMiklos Szeredi <mszeredi@redhat.com>
parent 191a3980

Documentation/filesystems/Locking

+1 −1
Original line number Diff line number Diff line
@@ -22,7 +22,7 @@ prototypes: 
	struct vfsmount *(*d_automount)(struct path *path);

	int (*d_manage)(const struct path *, bool);

	struct dentry *(*d_real)(struct dentry *, const struct inode *,

				 unsigned int);

				 unsigned int, unsigned int);



locking rules:

		rename_lock	->d_lock	may block	rcu-walk

Documentation/filesystems/vfs.txt

+1 −1
Original line number Diff line number Diff line
@@ -990,7 +990,7 @@ struct dentry_operations { 
	struct vfsmount *(*d_automount)(struct path *);

	int (*d_manage)(const struct path *, bool);

	struct dentry *(*d_real)(struct dentry *, const struct inode *,

				 unsigned int);

				 unsigned int, unsigned int);

};



  d_revalidate: called when the VFS needs to revalidate a dentry. This

fs/open.c

+2 −2
Original line number Diff line number Diff line
@@ -96,7 +96,7 @@ long vfs_truncate(const struct path *path, loff_t length) 
	 * write access on the upper inode, not on the overlay inode.  For

	 * non-overlay filesystems d_real() is an identity function.

	 */

	upperdentry = d_real(path->dentry, NULL, O_WRONLY);

	upperdentry = d_real(path->dentry, NULL, O_WRONLY, 0);

	error = PTR_ERR(upperdentry);

	if (IS_ERR(upperdentry))

		goto mnt_drop_write_and_out;
@@ -857,7 +857,7 @@ EXPORT_SYMBOL(file_path); 
int vfs_open(const struct path *path, struct file *file,

	     const struct cred *cred)

{

	struct dentry *dentry = d_real(path->dentry, NULL, file->f_flags);

	struct dentry *dentry = d_real(path->dentry, NULL, file->f_flags, 0);



	if (IS_ERR(dentry))

		return PTR_ERR(dentry);

fs/overlayfs/super.c

+2 −2
Original line number Diff line number Diff line
@@ -70,7 +70,7 @@ static int ovl_check_append_only(struct inode *inode, int flag) 


static struct dentry *ovl_d_real(struct dentry *dentry,

				 const struct inode *inode,

				 unsigned int open_flags)

				 unsigned int open_flags, unsigned int flags)

{

	struct dentry *real;

	int err;
@@ -102,7 +102,7 @@ static struct dentry *ovl_d_real(struct dentry *dentry, 
		goto bug;



	/* Handle recursion */

	real = d_real(real, inode, open_flags);

	real = d_real(real, inode, open_flags, 0);



	if (!inode || inode == d_inode(real))

		return real;

include/linux/dcache.h

+6 −5
Original line number Diff line number Diff line
@@ -147,7 +147,7 @@ struct dentry_operations { 
	struct vfsmount *(*d_automount)(struct path *);

	int (*d_manage)(const struct path *, bool);

	struct dentry *(*d_real)(struct dentry *, const struct inode *,

				 unsigned int);

				 unsigned int, unsigned int);

} ____cacheline_aligned;



/*
@@ -566,7 +566,8 @@ static inline struct dentry *d_backing_dentry(struct dentry *upper) 
 * d_real - Return the real dentry

 * @dentry: the dentry to query

 * @inode: inode to select the dentry from multiple layers (can be NULL)

 * @flags: open flags to control copy-up behavior

 * @open_flags: open flags to control copy-up behavior

 * @flags: flags to control what is returned by this function

 *

 * If dentry is on a union/overlay, then return the underlying, real dentry.

 * Otherwise return the dentry itself.
@@ -575,10 +576,10 @@ static inline struct dentry *d_backing_dentry(struct dentry *upper) 
 */

static inline struct dentry *d_real(struct dentry *dentry,

				    const struct inode *inode,

				    unsigned int flags)

				    unsigned int open_flags, unsigned int flags)

{

	if (unlikely(dentry->d_flags & DCACHE_OP_REAL))

		return dentry->d_op->d_real(dentry, inode, flags);

		return dentry->d_op->d_real(dentry, inode, open_flags, flags);

	else

		return dentry;

}
@@ -593,7 +594,7 @@ static inline struct dentry *d_real(struct dentry *dentry, 
static inline struct inode *d_real_inode(const struct dentry *dentry)

{

	/* This usage of d_real() results in const dentry */

	return d_backing_inode(d_real((struct dentry *) dentry, NULL, 0));

	return d_backing_inode(d_real((struct dentry *) dentry, NULL, 0, 0));

}



struct name_snapshot {