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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_H9#define FS_9P_V9FS_VFS_H10 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 atomic14 * open.15 * we track the create fid here. When the file is opened, if fidopen is16 * 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 open20 */21 22/* special case:23 * unlink calls remove, which is an implicit clunk. So we have to track24 * 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 130 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, 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#else50#define QID2INO(q) ((ino_t) ((q)->path+2))51#endif52 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 the82	 * 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#endif92