Push to branch refs/heads/master:
bcbcaeee3391c38657c817fe5231351c138d9a15 -->
95c4f83688f1db84eba492328a5a362e9f9ac54f
fs/wrapfs/lookup.c | 55 +++++++++++++++++++++++++++++++++++++-----------------
fs/wrapfs/main.c | 2 ++
fs/wrapfs/super.c | 40 +++++++++++++++++++++++++++++++++++++++
fs/wrapfs/wrapfs.h | 2 ++
4 files changed, 82 insertions(+), 17 deletions(-)
commit 95c4f83688f1db84eba492328a5a362e9f9ac54f
Author: Erez Zadok <e...@cs.sunysb.edu>
Date: Sun May 22 01:25:28 2016 -0400
Wrapfs: support NFS exports
Based on patch from Sandeep Joshi <sanjos...@gmail.com>.
Signed-off-by: Erez Zadok <e...@cs.sunysb.edu>
commit d9a0ce855703ec9109f4279f962b06e1ddda588c
Author: Erez Zadok <e...@cs.sunysb.edu>
Date: Sun May 22 01:25:28 2016 -0400
Wrapfs: use d_splice_alias
Refactor interpose code to allow lookup to use d_splice_alias.
Signed-off-by: Erez Zadok <e...@cs.sunysb.edu>
diff --git a/fs/wrapfs/lookup.c b/fs/wrapfs/lookup.c
index ef47e71..afa5063 100644
--- a/fs/wrapfs/lookup.c
+++ b/fs/wrapfs/lookup.c
@@ -144,27 +144,24 @@ struct inode *wrapfs_iget(struct super_block *sb, struct
inode *lower_inode)
}
/*
- * Connect a wrapfs inode dentry/inode with several lower ones. This is
- * the classic stackable file system "vnode interposition" action.
- *
- * @dentry: wrapfs's dentry which interposes on lower one
- * @sb: wrapfs's super_block
- * @lower_path: the lower path (caller does path_get/put)
+ * Helper interpose routine, called directly by ->lookup to handle
+ * spliced dentries.
*/
-int wrapfs_interpose(struct dentry *dentry, struct super_block *sb,
- struct path *lower_path)
+static struct dentry *__wrapfs_interpose(struct dentry *dentry,
+ struct super_block *sb,
+ struct path *lower_path)
{
- int err = 0;
struct inode *inode;
struct inode *lower_inode;
struct super_block *lower_sb;
+ struct dentry *ret_dentry;
lower_inode = lower_path->dentry->d_inode;
lower_sb = wrapfs_lower_super(sb);
/* check that the lower file system didn't cross a mount point */
if (lower_inode->i_sb != lower_sb) {
- err = -EXDEV;
+ ret_dentry = ERR_PTR(-EXDEV);
goto out;
}
@@ -176,14 +173,31 @@ int wrapfs_interpose(struct dentry *dentry, struct
super_block *sb,
/* inherit lower inode number for wrapfs's inode */
inode = wrapfs_iget(sb, lower_inode);
if (IS_ERR(inode)) {
- err = PTR_ERR(inode);
+ ret_dentry = ERR_PTR(PTR_ERR(inode));
goto out;
}
- d_add(dentry, inode);
+ ret_dentry = d_splice_alias(inode, dentry);
out:
- return err;
+ return ret_dentry;
+}
+
+/*
+ * Connect a wrapfs inode dentry/inode with several lower ones. This is
+ * the classic stackable file system "vnode interposition" action.
+ *
+ * @dentry: wrapfs's dentry which interposes on lower one
+ * @sb: wrapfs's super_block
+ * @lower_path: the lower path (caller does path_get/put)
+ */
+int wrapfs_interpose(struct dentry *dentry, struct super_block *sb,
+ struct path *lower_path)
+{
+ struct dentry *ret_dentry;
+
+ ret_dentry = __wrapfs_interpose(dentry, sb, lower_path);
+ return PTR_ERR(ret_dentry);
}
/*
@@ -202,6 +216,7 @@ static struct dentry *__wrapfs_lookup(struct dentry
*dentry, int flags,
const char *name;
struct path lower_path;
struct qstr this;
+ struct dentry *ret_dentry = NULL;
/* must initialize dentry operations */
d_set_d_op(dentry, &wrapfs_dops);
@@ -222,9 +237,13 @@ static struct dentry *__wrapfs_lookup(struct dentry
*dentry, int flags,
/* no error: handle positive dentries */
if (!err) {
wrapfs_set_lower_path(dentry, &lower_path);
- err = wrapfs_interpose(dentry, dentry->d_sb, &lower_path);
- if (err) /* path_put underlying path on error */
+ ret_dentry =
+ __wrapfs_interpose(dentry, dentry->d_sb, &lower_path);
+ if (IS_ERR(ret_dentry)) {
+ err = PTR_ERR(ret_dentry);
+ /* path_put underlying path on error */
wrapfs_put_reset_lower_path(dentry);
+ }
goto out;
}
@@ -260,11 +279,13 @@ setup_lower:
* the VFS will continue the process of making this negative dentry
* into a positive one.
*/
- if (flags & (LOOKUP_CREATE|LOOKUP_RENAME_TARGET))
+ if (err == -ENOENT || (flags & (LOOKUP_CREATE|LOOKUP_RENAME_TARGET)))
err = 0;
out:
- return ERR_PTR(err);
+ if (err)
+ return ERR_PTR(err);
+ return ret_dentry;
}
struct dentry *wrapfs_lookup(struct inode *dir, struct dentry *dentry,
diff --git a/fs/wrapfs/main.c b/fs/wrapfs/main.c
index b3042b6..71d11cf 100644
--- a/fs/wrapfs/main.c
+++ b/fs/wrapfs/main.c
@@ -64,6 +64,8 @@ static int wrapfs_read_super(struct super_block *sb, void
*raw_data, int silent)
sb->s_op = &wrapfs_sops;
+ sb->s_export_op = &wrapfs_export_ops; /* adding NFS support */
+
/* get a new inode and allocate our root dentry */
inode = wrapfs_iget(sb, lower_path.dentry->d_inode);
if (IS_ERR(inode)) {
diff --git a/fs/wrapfs/super.c b/fs/wrapfs/super.c
index 9f90f57..5c99c47 100644
--- a/fs/wrapfs/super.c
+++ b/fs/wrapfs/super.c
@@ -166,3 +166,43 @@ const struct super_operations wrapfs_sops = {
.destroy_inode = wrapfs_destroy_inode,
.drop_inode = generic_delete_inode,
};
+
+/* NFS support */
+
+static struct inode *wrapfs_nfs_get_inode(struct super_block *sb, u64 ino,
+ u32 generation)
+{
+ struct super_block *lower_sb;
+ struct inode *inode;
+ struct inode *lower_inode;
+
+ lower_sb = wrapfs_lower_super(sb);
+ lower_inode = ilookup(lower_sb, ino);
+ inode = wrapfs_iget(sb, lower_inode);
+ return inode;
+}
+
+static struct dentry *wrapfs_fh_to_dentry(struct super_block *sb,
+ struct fid *fid, int fh_len,
+ int fh_type)
+{
+ return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
+ wrapfs_nfs_get_inode);
+}
+
+static struct dentry *wrapfs_fh_to_parent(struct super_block *sb,
+ struct fid *fid, int fh_len,
+ int fh_type)
+{
+ return generic_fh_to_parent(sb, fid, fh_len, fh_type,
+ wrapfs_nfs_get_inode);
+}
+
+/*
+ * all other funcs are default as defined in exportfs/expfs.c
+ */
+
+const struct export_operations wrapfs_export_ops = {
+ .fh_to_dentry = wrapfs_fh_to_dentry,
+ .fh_to_parent = wrapfs_fh_to_parent
+};
diff --git a/fs/wrapfs/wrapfs.h b/fs/wrapfs/wrapfs.h
index 4cdf884..93d2643 100644
--- a/fs/wrapfs/wrapfs.h
+++ b/fs/wrapfs/wrapfs.h
@@ -27,6 +27,7 @@
#include <linux/slab.h>
#include <linux/sched.h>
#include <linux/xattr.h>
+#include <linux/exportfs.h>
/* the file system name */
#define WRAPFS_NAME "wrapfs"
@@ -47,6 +48,7 @@ extern const struct super_operations wrapfs_sops;
extern const struct dentry_operations wrapfs_dops;
extern const struct address_space_operations wrapfs_aops, wrapfs_dummy_aops;
extern const struct vm_operations_struct wrapfs_vm_ops;
+extern const struct export_operations wrapfs_export_ops;
extern int wrapfs_init_inode_cache(void);
extern void wrapfs_destroy_inode_cache(void);
_______________________________________________
unionfs-cvs mailing list: http://unionfs.filesystems.org/
unionfs-cvs@fsl.cs.sunysb.edu
http://www.fsl.cs.sunysb.edu/mailman/listinfo/unionfs-cvs
