Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 2bc334dc authored by Nick Piggin's avatar Nick Piggin
Browse files

jfs: dont overwrite dentry name in d_revalidate 



Use vfat's method for dealing with negative dentries to preserve case,
rather than overwrite dentry name in d_revalidate, which is a bit ugly
and also gets in the way of doing lock-free path walking.

Signed-off-by: default avatarNick Piggin <npiggin@kernel.dk>
parent 79eb4dde

fs/jfs/namei.c

+35 −8
Original line number Diff line number Diff line
@@ -18,6 +18,7 @@ 
 */



#include <linux/fs.h>

#include <linux/namei.h>

#include <linux/ctype.h>

#include <linux/quotaops.h>

#include <linux/exportfs.h>
@@ -1597,21 +1598,47 @@ static int jfs_ci_compare(struct dentry *dir, struct qstr *a, struct qstr *b) 
			goto out;

	}

	result = 0;

out:

	return result;

}



static int jfs_ci_revalidate(struct dentry *dentry, struct nameidata *nd)

{

	/*

	 * We want creates to preserve case.  A negative dentry, a, that

	 * has a different case than b may cause a new entry to be created

	 * with the wrong case.  Since we can't tell if a comes from a negative

	 * dentry, we blindly replace it with b.  This should be harmless if

	 * a is not a negative dentry.

	 * This is not negative dentry. Always valid.

	 *

	 * Note, rename() to existing directory entry will have ->d_inode,

	 * and will use existing name which isn't specified name by user.

	 *

	 * We may be able to drop this positive dentry here. But dropping

	 * positive dentry isn't good idea. So it's unsupported like

	 * rename("filename", "FILENAME") for now.

	 */

	memcpy((unsigned char *)a->name, b->name, a->len);

out:

	return result;

	if (dentry->d_inode)

		return 1;



	/*

	 * This may be nfsd (or something), anyway, we can't see the

	 * intent of this. So, since this can be for creation, drop it.

	 */

	if (!nd)

		return 0;



	/*

	 * Drop the negative dentry, in order to make sure to use the

	 * case sensitive name which is specified by user if this is

	 * for creation.

	 */

	if (!(nd->flags & (LOOKUP_CONTINUE | LOOKUP_PARENT))) {

		if (nd->flags & (LOOKUP_CREATE | LOOKUP_RENAME_TARGET))

			return 0;

	}

	return 1;

}



const struct dentry_operations jfs_ci_dentry_operations =

{

	.d_hash = jfs_ci_hash,

	.d_compare = jfs_ci_compare,

	.d_revalidate = jfs_ci_revalidate,

};