VFS: Allow the filesystem to return a full file pointer on open intent
This is needed by NFSv4 for atomicity reasons: our open command is in
fact a lookup+open, so we need to be able to propagate open context
information from lookup() into the resulting struct file's
private_data field.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
diff --git a/fs/exec.c b/fs/exec.c
index a04a575..d2208f7 100644
--- a/fs/exec.c
+++ b/fs/exec.c
@@ -126,8 +126,7 @@
struct nameidata nd;
int error;
- nd.intent.open.flags = FMODE_READ;
- error = __user_walk(library, LOOKUP_FOLLOW|LOOKUP_OPEN, &nd);
+ error = __user_path_lookup_open(library, LOOKUP_FOLLOW, &nd, FMODE_READ);
if (error)
goto out;
@@ -139,7 +138,7 @@
if (error)
goto exit;
- file = dentry_open(nd.dentry, nd.mnt, O_RDONLY);
+ file = nameidata_to_filp(&nd, O_RDONLY);
error = PTR_ERR(file);
if (IS_ERR(file))
goto out;
@@ -167,6 +166,7 @@
out:
return error;
exit:
+ release_open_intent(&nd);
path_release(&nd);
goto out;
}
@@ -490,8 +490,7 @@
int err;
struct file *file;
- nd.intent.open.flags = FMODE_READ;
- err = path_lookup(name, LOOKUP_FOLLOW|LOOKUP_OPEN, &nd);
+ err = path_lookup_open(name, LOOKUP_FOLLOW, &nd, FMODE_READ);
file = ERR_PTR(err);
if (!err) {
@@ -504,7 +503,7 @@
err = -EACCES;
file = ERR_PTR(err);
if (!err) {
- file = dentry_open(nd.dentry, nd.mnt, O_RDONLY);
+ file = nameidata_to_filp(&nd, O_RDONLY);
if (!IS_ERR(file)) {
err = deny_write_access(file);
if (err) {
@@ -516,6 +515,7 @@
return file;
}
}
+ release_open_intent(&nd);
path_release(&nd);
}
goto out;