Revert "UBUNTU: SAUCE: overlayfs -- vfs: add i_op->open()"

This reverts commit b1735a53c10c6c16590a6a7bf6f1f78ae2c3a636.

Signed-off-by: Andy Whitcroft <apw@canonical.com>

diff --git a/fs/open.c b/fs/open.c
index f93938d..3ed2001 100644 (file)
--- a/fs/open.c
+++ b/fs/open.c
@@ -648,7 +648,8 @@ static inline int __get_file_write_access(struct inode *inode,
        return error;
 }
 
-static struct file *__dentry_open(struct path *path, struct file *f,
+static struct file *__dentry_open(struct dentry *dentry, struct vfsmount *mnt,
+                                       struct file *f,
                                        int (*open)(struct inode *, struct file *),
                                        const struct cred *cred)
 {
@@ -656,16 +657,15 @@ static struct file *__dentry_open(struct path *path, struct file *f,
        struct inode *inode;
        int error;
 
-       path_get(path);
        f->f_mode = OPEN_FMODE(f->f_flags) | FMODE_LSEEK |
                                FMODE_PREAD | FMODE_PWRITE;
 
        if (unlikely(f->f_flags & O_PATH))
                f->f_mode = FMODE_PATH;
 
-       inode = path->dentry->d_inode;
+       inode = dentry->d_inode;
        if (f->f_mode & FMODE_WRITE) {
-               error = __get_file_write_access(inode, path->mnt);
+               error = __get_file_write_access(inode, mnt);
                if (error)
                        goto cleanup_file;
                if (!special_file(inode->i_mode))
@@ -673,7 +673,8 @@ static struct file *__dentry_open(struct path *path, struct file *f,
        }
 
        f->f_mapping = inode->i_mapping;
-       f->f_path = *path;
+       f->f_path.dentry = dentry;
+       f->f_path.mnt = mnt;
        f->f_pos = 0;
        file_sb_list_add(f, inode->i_sb);
 
@@ -730,7 +731,7 @@ cleanup_all:
                         * here, so just reset the state.
                         */
                        file_reset_write(f);
-                       mnt_drop_write(path->mnt);
+                       mnt_drop_write(mnt);
                }
        }
        file_sb_list_del(f);
@@ -738,7 +739,8 @@ cleanup_all:
        f->f_path.mnt = NULL;
 cleanup_file:
        put_filp(f);
-       path_put(path);
+       dput(dentry);
+       mntput(mnt);
        return ERR_PTR(error);
 }
 
@@ -764,14 +766,14 @@ cleanup_file:
 struct file *lookup_instantiate_filp(struct nameidata *nd, struct dentry *dentry,
                int (*open)(struct inode *, struct file *))
 {
-       struct path path = { .dentry = dentry, .mnt = nd->path.mnt };
        const struct cred *cred = current_cred();
 
        if (IS_ERR(nd->intent.open.file))
                goto out;
        if (IS_ERR(dentry))
                goto out_err;
-       nd->intent.open.file = __dentry_open(&path, nd->intent.open.file,
+       nd->intent.open.file = __dentry_open(dget(dentry), mntget(nd->path.mnt),
+                                            nd->intent.open.file,
                                             open, cred);
 out:
        return nd->intent.open.file;
@@ -800,17 +802,10 @@ struct file *nameidata_to_filp(struct nameidata *nd)
 
        /* Has the filesystem initialised the file for us? */
        if (filp->f_path.dentry == NULL) {
-               struct inode *inode = nd->path.dentry->d_inode;
-
-               if (inode->i_op->open) {
-                       int flags = filp->f_flags;
-                       put_filp(filp);
-                       filp = inode->i_op->open(nd->path.dentry, flags, cred);
-               } else {
-                       filp = __dentry_open(&nd->path, filp, NULL, cred);
-               }
+               path_get(&nd->path);
+               filp = __dentry_open(nd->path.dentry, nd->path.mnt, filp,
+                                    NULL, cred);
        }
-
        return filp;
 }
 
@@ -821,45 +816,26 @@ struct file *nameidata_to_filp(struct nameidata *nd)
 struct file *dentry_open(struct dentry *dentry, struct vfsmount *mnt, int flags,
                         const struct cred *cred)
 {
-       struct path path = { .dentry = dentry, .mnt = mnt };
-       struct file *ret;
-
-       /* We must always pass in a valid mount pointer. */
-       BUG_ON(!mnt);
-
-       ret = vfs_open(&path, flags, cred);
-       path_put(&path);
-
-       return ret;
-}
-EXPORT_SYMBOL(dentry_open);
-
-/**
- * vfs_open - open the file at the given path
- * @path: path to open
- * @flags: open flags
- * @cred: credentials to use
- *
- * Open the file.  If successful, the returned file will have acquired
- * an additional reference for path.
- */
-struct file *vfs_open(struct path *path, int flags, const struct cred *cred)
-{
+       int error;
        struct file *f;
-       struct inode *inode = path->dentry->d_inode;
 
        validate_creds(cred);
 
-       if (inode->i_op->open)
-               return inode->i_op->open(path->dentry, flags, cred);
+       /* We must always pass in a valid mount pointer. */
+       BUG_ON(!mnt);
+
+       error = -ENFILE;
        f = get_empty_filp();
-       if (f == NULL)
-               return ERR_PTR(-ENFILE);
+       if (f == NULL) {
+               dput(dentry);
+               mntput(mnt);
+               return ERR_PTR(error);
+       }
 
        f->f_flags = flags;
-       return __dentry_open(path, f, NULL, cred);
+       return __dentry_open(dentry, mnt, f, NULL, cred);
 }
-EXPORT_SYMBOL(vfs_open);
+EXPORT_SYMBOL(dentry_open);
 
 static void __put_unused_fd(struct files_struct *files, unsigned int fd)
 {

diff --git a/include/linux/fs.h b/include/linux/fs.h
index 737ce9c..10b2288 100644 (file)
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -1639,7 +1639,6 @@ struct inode_operations {
        void (*truncate_range)(struct inode *, loff_t, loff_t);
        int (*fiemap)(struct inode *, struct fiemap_extent_info *, u64 start,
                      u64 len);
-       struct file *(*open)(struct dentry *, int flags, const struct cred *);
 } ____cacheline_aligned;
 
 struct seq_file;
@@ -2060,7 +2059,6 @@ extern long do_sys_open(int dfd, const char __user *filename, int flags,
 extern struct file *filp_open(const char *, int, int);
 extern struct file *file_open_root(struct dentry *, struct vfsmount *,
                                   const char *, int);
-extern struct file *vfs_open(struct path *, int flags, const struct cred *);
 extern struct file * dentry_open(struct dentry *, struct vfsmount *, int,
                                 const struct cred *);
 extern int filp_close(struct file *, fl_owner_t id);