v4.19.13 snapshot.
diff --git a/fs/9p/v9fs.h b/fs/9p/v9fs.h
new file mode 100644
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--- /dev/null
+++ b/fs/9p/v9fs.h
@@ -0,0 +1,228 @@
+/*
+ * V9FS definitions.
+ *
+ * Copyright (C) 2004-2008 by Eric Van Hensbergen <ericvh@gmail.com>
+ * Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2
+ * as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to:
+ * Free Software Foundation
+ * 51 Franklin Street, Fifth Floor
+ * Boston, MA 02111-1301 USA
+ *
+ */
+#ifndef FS_9P_V9FS_H
+#define FS_9P_V9FS_H
+
+#include <linux/backing-dev.h>
+
+/**
+ * enum p9_session_flags - option flags for each 9P session
+ * @V9FS_PROTO_2000U: whether or not to use 9P2000.u extensions
+ * @V9FS_PROTO_2000L: whether or not to use 9P2000.l extensions
+ * @V9FS_ACCESS_SINGLE: only the mounting user can access the hierarchy
+ * @V9FS_ACCESS_USER: a new attach will be issued for every user (default)
+ * @V9FS_ACCESS_CLIENT: Just like user, but access check is performed on client.
+ * @V9FS_ACCESS_ANY: use a single attach for all users
+ * @V9FS_ACCESS_MASK: bit mask of different ACCESS options
+ * @V9FS_POSIX_ACL: POSIX ACLs are enforced
+ *
+ * Session flags reflect options selected by users at mount time
+ */
+#define V9FS_ACCESS_ANY (V9FS_ACCESS_SINGLE | \
+ V9FS_ACCESS_USER | \
+ V9FS_ACCESS_CLIENT)
+#define V9FS_ACCESS_MASK V9FS_ACCESS_ANY
+#define V9FS_ACL_MASK V9FS_POSIX_ACL
+
+enum p9_session_flags {
+ V9FS_PROTO_2000U = 0x01,
+ V9FS_PROTO_2000L = 0x02,
+ V9FS_ACCESS_SINGLE = 0x04,
+ V9FS_ACCESS_USER = 0x08,
+ V9FS_ACCESS_CLIENT = 0x10,
+ V9FS_POSIX_ACL = 0x20
+};
+
+/* possible values of ->cache */
+/**
+ * enum p9_cache_modes - user specified cache preferences
+ * @CACHE_NONE: do not cache data, dentries, or directory contents (default)
+ * @CACHE_LOOSE: cache data, dentries, and directory contents w/no consistency
+ *
+ * eventually support loose, tight, time, session, default always none
+ */
+
+enum p9_cache_modes {
+ CACHE_NONE,
+ CACHE_MMAP,
+ CACHE_LOOSE,
+ CACHE_FSCACHE,
+ nr__p9_cache_modes
+};
+
+/**
+ * struct v9fs_session_info - per-instance session information
+ * @flags: session options of type &p9_session_flags
+ * @nodev: set to 1 to disable device mapping
+ * @debug: debug level
+ * @afid: authentication handle
+ * @cache: cache mode of type &p9_cache_modes
+ * @cachetag: the tag of the cache associated with this session
+ * @fscache: session cookie associated with FS-Cache
+ * @uname: string user name to mount hierarchy as
+ * @aname: mount specifier for remote hierarchy
+ * @maxdata: maximum data to be sent/recvd per protocol message
+ * @dfltuid: default numeric userid to mount hierarchy as
+ * @dfltgid: default numeric groupid to mount hierarchy as
+ * @uid: if %V9FS_ACCESS_SINGLE, the numeric uid which mounted the hierarchy
+ * @clnt: reference to 9P network client instantiated for this session
+ * @slist: reference to list of registered 9p sessions
+ *
+ * This structure holds state for each session instance established during
+ * a sys_mount() .
+ *
+ * Bugs: there seems to be a lot of state which could be condensed and/or
+ * removed.
+ */
+
+struct v9fs_session_info {
+ /* options */
+ unsigned char flags;
+ unsigned char nodev;
+ unsigned short debug;
+ unsigned int afid;
+ unsigned int cache;
+#ifdef CONFIG_9P_FSCACHE
+ char *cachetag;
+ struct fscache_cookie *fscache;
+#endif
+
+ char *uname; /* user name to mount as */
+ char *aname; /* name of remote hierarchy being mounted */
+ unsigned int maxdata; /* max data for client interface */
+ kuid_t dfltuid; /* default uid/muid for legacy support */
+ kgid_t dfltgid; /* default gid for legacy support */
+ kuid_t uid; /* if ACCESS_SINGLE, the uid that has access */
+ struct p9_client *clnt; /* 9p client */
+ struct list_head slist; /* list of sessions registered with v9fs */
+ struct rw_semaphore rename_sem;
+};
+
+/* cache_validity flags */
+#define V9FS_INO_INVALID_ATTR 0x01
+
+struct v9fs_inode {
+#ifdef CONFIG_9P_FSCACHE
+ struct mutex fscache_lock;
+ struct fscache_cookie *fscache;
+#endif
+ struct p9_qid qid;
+ unsigned int cache_validity;
+ struct p9_fid *writeback_fid;
+ struct mutex v_mutex;
+ struct inode vfs_inode;
+};
+
+static inline struct v9fs_inode *V9FS_I(const struct inode *inode)
+{
+ return container_of(inode, struct v9fs_inode, vfs_inode);
+}
+
+extern int v9fs_show_options(struct seq_file *m, struct dentry *root);
+
+struct p9_fid *v9fs_session_init(struct v9fs_session_info *, const char *,
+ char *);
+extern void v9fs_session_close(struct v9fs_session_info *v9ses);
+extern void v9fs_session_cancel(struct v9fs_session_info *v9ses);
+extern void v9fs_session_begin_cancel(struct v9fs_session_info *v9ses);
+extern struct dentry *v9fs_vfs_lookup(struct inode *dir, struct dentry *dentry,
+ unsigned int flags);
+extern int v9fs_vfs_unlink(struct inode *i, struct dentry *d);
+extern int v9fs_vfs_rmdir(struct inode *i, struct dentry *d);
+extern int v9fs_vfs_rename(struct inode *old_dir, struct dentry *old_dentry,
+ struct inode *new_dir, struct dentry *new_dentry,
+ unsigned int flags);
+extern struct inode *v9fs_inode_from_fid(struct v9fs_session_info *v9ses,
+ struct p9_fid *fid,
+ struct super_block *sb, int new);
+extern const struct inode_operations v9fs_dir_inode_operations_dotl;
+extern const struct inode_operations v9fs_file_inode_operations_dotl;
+extern const struct inode_operations v9fs_symlink_inode_operations_dotl;
+extern struct inode *v9fs_inode_from_fid_dotl(struct v9fs_session_info *v9ses,
+ struct p9_fid *fid,
+ struct super_block *sb, int new);
+
+/* other default globals */
+#define V9FS_PORT 564
+#define V9FS_DEFUSER "nobody"
+#define V9FS_DEFANAME ""
+#define V9FS_DEFUID KUIDT_INIT(-2)
+#define V9FS_DEFGID KGIDT_INIT(-2)
+
+static inline struct v9fs_session_info *v9fs_inode2v9ses(struct inode *inode)
+{
+ return (inode->i_sb->s_fs_info);
+}
+
+static inline struct v9fs_session_info *v9fs_dentry2v9ses(struct dentry *dentry)
+{
+ return dentry->d_sb->s_fs_info;
+}
+
+static inline int v9fs_proto_dotu(struct v9fs_session_info *v9ses)
+{
+ return v9ses->flags & V9FS_PROTO_2000U;
+}
+
+static inline int v9fs_proto_dotl(struct v9fs_session_info *v9ses)
+{
+ return v9ses->flags & V9FS_PROTO_2000L;
+}
+
+/**
+ * v9fs_get_inode_from_fid - Helper routine to populate an inode by
+ * issuing a attribute request
+ * @v9ses: session information
+ * @fid: fid to issue attribute request for
+ * @sb: superblock on which to create inode
+ *
+ */
+static inline struct inode *
+v9fs_get_inode_from_fid(struct v9fs_session_info *v9ses, struct p9_fid *fid,
+ struct super_block *sb)
+{
+ if (v9fs_proto_dotl(v9ses))
+ return v9fs_inode_from_fid_dotl(v9ses, fid, sb, 0);
+ else
+ return v9fs_inode_from_fid(v9ses, fid, sb, 0);
+}
+
+/**
+ * v9fs_get_new_inode_from_fid - Helper routine to populate an inode by
+ * issuing a attribute request
+ * @v9ses: session information
+ * @fid: fid to issue attribute request for
+ * @sb: superblock on which to create inode
+ *
+ */
+static inline struct inode *
+v9fs_get_new_inode_from_fid(struct v9fs_session_info *v9ses, struct p9_fid *fid,
+ struct super_block *sb)
+{
+ if (v9fs_proto_dotl(v9ses))
+ return v9fs_inode_from_fid_dotl(v9ses, fid, sb, 1);
+ else
+ return v9fs_inode_from_fid(v9ses, fid, sb, 1);
+}
+
+#endif