1/* SPDX-License-Identifier: GPL-2.0-only */
2/*
3 * V9FS VFS extensions.
4 *
5 *  Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
6 *  Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
7 */
8#ifndef FS_9P_V9FS_VFS_H
9#define FS_9P_V9FS_VFS_H
10
11/* plan9 semantics are that created files are implicitly opened.
12 * But linux semantics are that you call create, then open.
13 * the plan9 approach is superior as it provides an atomic
14 * open.
15 * we track the create fid here. When the file is opened, if fidopen is
16 * non-zero, we use the fid and can skip some steps.
17 * there may be a better way to do this, but I don't know it.
18 * one BAD way is to clunk the fid on create, then open it again:
19 * you lose the atomicity of file open
20 */
21
22/* special case:
23 * unlink calls remove, which is an implicit clunk. So we have to track
24 * that kind of thing so that we don't try to clunk a dead fid.
25 */
26#define P9_LOCK_TIMEOUT (30*HZ)
27
28/* flags for v9fs_stat2inode() & v9fs_stat2inode_dotl() */
29#define V9FS_STAT2INODE_KEEP_ISIZE 1
30
31extern struct file_system_type v9fs_fs_type;
32extern const struct address_space_operations v9fs_addr_operations;
33extern const struct file_operations v9fs_file_operations;
34extern const struct file_operations v9fs_file_operations_dotl;
35extern const struct file_operations v9fs_dir_operations;
36extern const struct file_operations v9fs_dir_operations_dotl;
37extern const struct dentry_operations v9fs_dentry_operations;
38extern const struct dentry_operations v9fs_cached_dentry_operations;
39extern struct kmem_cache *v9fs_inode_cache;
40
41struct inode *v9fs_alloc_inode(struct super_block *sb);
42void v9fs_free_inode(struct inode *inode);
43void v9fs_set_netfs_context(struct inode *inode);
44int v9fs_init_inode(struct v9fs_session_info *v9ses,
45		    struct inode *inode, struct p9_qid *qid, umode_t mode, dev_t rdev);
46void v9fs_evict_inode(struct inode *inode);
47#if (BITS_PER_LONG == 32)
48#define QID2INO(q) ((ino_t) (((q)->path+2) ^ (((q)->path) >> 32)))
49#else
50#define QID2INO(q) ((ino_t) ((q)->path+2))
51#endif
52
53void v9fs_stat2inode(struct p9_wstat *stat, struct inode *inode,
54		      struct super_block *sb, unsigned int flags);
55void v9fs_stat2inode_dotl(struct p9_stat_dotl *stat, struct inode *inode,
56			   unsigned int flags);
57int v9fs_dir_release(struct inode *inode, struct file *filp);
58int v9fs_file_open(struct inode *inode, struct file *file);
59int v9fs_uflags2omode(int uflags, int extended);
60
61void v9fs_blank_wstat(struct p9_wstat *wstat);
62int v9fs_vfs_setattr_dotl(struct mnt_idmap *idmap,
63			  struct dentry *dentry, struct iattr *iattr);
64int v9fs_file_fsync_dotl(struct file *filp, loff_t start, loff_t end,
65			 int datasync);
66int v9fs_refresh_inode(struct p9_fid *fid, struct inode *inode);
67int v9fs_refresh_inode_dotl(struct p9_fid *fid, struct inode *inode);
68static inline void v9fs_invalidate_inode_attr(struct inode *inode)
69{
70	struct v9fs_inode *v9inode;
71
72	v9inode = V9FS_I(inode);
73	v9inode->cache_validity |= V9FS_INO_INVALID_ATTR;
74}
75
76int v9fs_open_to_dotl_flags(int flags);
77
78static inline void v9fs_i_size_write(struct inode *inode, loff_t i_size)
79{
80	/*
81	 * 32-bit need the lock, concurrent updates could break the
82	 * sequences and make i_size_read() loop forever.
83	 * 64-bit updates are atomic and can skip the locking.
84	 */
85	if (sizeof(i_size) > sizeof(long))
86		spin_lock(&inode->i_lock);
87	i_size_write(inode, i_size);
88	if (sizeof(i_size) > sizeof(long))
89		spin_unlock(&inode->i_lock);
90}
91#endif
92