[patch 19/24] vfs: add path_symlink()

[Miklos Szeredi <miklos@szeredi.hu>]

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From: Miklos Szeredi <mszeredi@suse.cz>

Introduce path_symlink().  Make vfs_symlink() static.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
---
 fs/ecryptfs/inode.c |   14 +++++++-------
 fs/namei.c          |   26 ++++++++++++++++++--------
 fs/nfsd/vfs.c       |   12 ++++--------
 include/linux/fs.h  |    2 +-
 4 files changed, 30 insertions(+), 24 deletions(-)

Index: linux-2.6/fs/ecryptfs/inode.c
===================================================================
--- linux-2.6.orig/fs/ecryptfs/inode.c	2008-05-06 11:04:39.000000000 +0200
+++ linux-2.6/fs/ecryptfs/inode.c	2008-05-06 11:04:40.000000000 +0200
@@ -439,7 +439,7 @@ static int ecryptfs_symlink(struct inode
 {
 	int rc;
 	struct dentry *lower_dentry;
-	struct dentry *lower_dir_dentry;
+	struct path lower_dir;
 	umode_t mode;
 	char *encoded_symname;
 	int encoded_symlen;
@@ -447,7 +447,8 @@ static int ecryptfs_symlink(struct inode
 
 	lower_dentry = ecryptfs_dentry_to_lower(dentry);
 	dget(lower_dentry);
-	lower_dir_dentry = lock_parent(lower_dentry);
+	lower_dir.mnt = ecryptfs_dentry_to_lower_mnt(dentry);
+	lower_dir.dentry = lock_parent(lower_dentry);
 	mode = S_IALLUGO;
 	encoded_symlen = ecryptfs_encode_filename(crypt_stat, symname,
 						  strlen(symname),
@@ -456,18 +457,17 @@ static int ecryptfs_symlink(struct inode
 		rc = encoded_symlen;
 		goto out_lock;
 	}
-	rc = vfs_symlink(lower_dir_dentry->d_inode, lower_dentry,
-			 encoded_symname, mode);
+	rc = path_symlink(&lower_dir, lower_dentry, encoded_symname, mode);
 	kfree(encoded_symname);
 	if (rc || !lower_dentry->d_inode)
 		goto out_lock;
 	rc = ecryptfs_interpose(lower_dentry, dentry, dir->i_sb, 0);
 	if (rc)
 		goto out_lock;
-	fsstack_copy_attr_times(dir, lower_dir_dentry->d_inode);
-	fsstack_copy_inode_size(dir, lower_dir_dentry->d_inode);
+	fsstack_copy_attr_times(dir, lower_dir.dentry->d_inode);
+	fsstack_copy_inode_size(dir, lower_dir.dentry->d_inode);
 out_lock:
-	unlock_dir(lower_dir_dentry);
+	unlock_dir(lower_dir.dentry);
 	dput(lower_dentry);
 	if (!dentry->d_inode)
 		d_drop(dentry);
Index: linux-2.6/fs/namei.c
===================================================================
--- linux-2.6.orig/fs/namei.c	2008-05-06 11:04:39.000000000 +0200
+++ linux-2.6/fs/namei.c	2008-05-06 11:04:40.000000000 +0200
@@ -2435,7 +2435,7 @@ asmlinkage long sys_unlink(const char __
 	return do_unlinkat(AT_FDCWD, pathname);
 }
 
-int vfs_symlink(struct inode *dir, struct dentry *dentry, const char *oldname, int mode)
+static int vfs_symlink(struct inode *dir, struct dentry *dentry, const char *oldname, int mode)
 {
 	int error = may_create(dir, dentry, NULL);
 
@@ -2456,6 +2456,22 @@ int vfs_symlink(struct inode *dir, struc
 	return error;
 }
 
+int path_symlink(struct path *dir_path, struct dentry *dentry,
+		 const char *oldname, int mode)
+{
+	int error = mnt_want_write(dir_path->mnt);
+
+	if (!error) {
+		struct inode *dir = dir_path->dentry->d_inode;
+
+		error = vfs_symlink(dir, dentry, oldname, mode);
+		mnt_drop_write(dir_path->mnt);
+	}
+
+	return error;
+}
+EXPORT_SYMBOL(path_symlink);
+
 asmlinkage long sys_symlinkat(const char __user *oldname,
 			      int newdfd, const char __user *newname)
 {
@@ -2481,12 +2497,7 @@ asmlinkage long sys_symlinkat(const char
 	if (IS_ERR(dentry))
 		goto out_unlock;
 
-	error = mnt_want_write(nd.path.mnt);
-	if (error)
-		goto out_dput;
-	error = vfs_symlink(nd.path.dentry->d_inode, dentry, from, S_IALLUGO);
-	mnt_drop_write(nd.path.mnt);
-out_dput:
+	error = path_symlink(&nd.path, dentry, from, S_IALLUGO);
 	dput(dentry);
 out_unlock:
 	mutex_unlock(&nd.path.dentry->d_inode->i_mutex);
@@ -3010,6 +3021,5 @@ EXPORT_SYMBOL(vfs_link);
 EXPORT_SYMBOL(generic_permission);
 EXPORT_SYMBOL(vfs_readlink);
 EXPORT_SYMBOL(vfs_rename);
-EXPORT_SYMBOL(vfs_symlink);
 EXPORT_SYMBOL(dentry_unhash);
 EXPORT_SYMBOL(generic_readlink);
Index: linux-2.6/fs/nfsd/vfs.c
===================================================================
--- linux-2.6.orig/fs/nfsd/vfs.c	2008-05-06 11:04:39.000000000 +0200
+++ linux-2.6/fs/nfsd/vfs.c	2008-05-06 11:04:40.000000000 +0200
@@ -1518,6 +1518,7 @@ nfsd_symlink(struct svc_rqst *rqstp, str
 				struct svc_fh *resfhp,
 				struct iattr *iap)
 {
+	struct path 	dir_path;
 	struct dentry	*dentry, *dnew;
 	__be32		err, cerr;
 	int		host_err;
@@ -1545,10 +1546,7 @@ nfsd_symlink(struct svc_rqst *rqstp, str
 	if (iap && (iap->ia_valid & ATTR_MODE))
 		mode = iap->ia_mode & S_IALLUGO;
 
-	host_err = mnt_want_write(fhp->fh_export->ex_path.mnt);
-	if (host_err)
-		goto out_nfserr;
-
+	fh_to_path(fhp, &dir_path);
 	if (unlikely(path[plen] != 0)) {
 		char *path_alloced = kmalloc(plen+1, GFP_KERNEL);
 		if (path_alloced == NULL)
@@ -1556,11 +1554,11 @@ nfsd_symlink(struct svc_rqst *rqstp, str
 		else {
 			strncpy(path_alloced, path, plen);
 			path_alloced[plen] = 0;
-			host_err = vfs_symlink(dentry->d_inode, dnew, path_alloced, mode);
+			host_err = path_symlink(&dir_path, dnew, path_alloced, mode);
 			kfree(path_alloced);
 		}
 	} else
-		host_err = vfs_symlink(dentry->d_inode, dnew, path, mode);
+		host_err = path_symlink(&dir_path, dnew, path, mode);
 
 	if (!host_err) {
 		if (EX_ISSYNC(fhp->fh_export))
@@ -1569,8 +1567,6 @@ nfsd_symlink(struct svc_rqst *rqstp, str
 	err = nfserrno(host_err);
 	fh_unlock(fhp);
 
-	mnt_drop_write(fhp->fh_export->ex_path.mnt);
-
 	cerr = fh_compose(resfhp, fhp->fh_export, dnew, fhp);
 	dput(dnew);
 	if (err==0) err = cerr;
Index: linux-2.6/include/linux/fs.h
===================================================================
--- linux-2.6.orig/include/linux/fs.h	2008-05-06 11:04:39.000000000 +0200
+++ linux-2.6/include/linux/fs.h	2008-05-06 11:04:40.000000000 +0200
@@ -1127,7 +1127,7 @@ extern int vfs_permission(struct nameida
 extern int path_create(struct path *, struct dentry *, int, struct nameidata *);
 extern int path_mkdir(struct path *, struct dentry *, int);
 extern int path_mknod(struct path *, struct dentry *, int, dev_t);
-extern int vfs_symlink(struct inode *, struct dentry *, const char *, int);
+extern int path_symlink(struct path *, struct dentry *, const char *, int);
 extern int vfs_link(struct dentry *, struct inode *, struct dentry *);
 extern int path_rmdir(struct path *, struct dentry *);
 extern int path_unlink(struct path *, struct dentry *);

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