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torvalds
GitHub Repository: torvalds/linux
 Path: blob/master/fs/9p/v9fs_vfs.h
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/* SPDX-License-Identifier: GPL-2.0-only */

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/*

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 * V9FS VFS extensions.

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 *

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 *  Copyright (C) 2004 by Eric Van Hensbergen <[email protected]>

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 *  Copyright (C) 2002 by Ron Minnich <[email protected]>

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 */

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#ifndef FS_9P_V9FS_VFS_H

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#define FS_9P_V9FS_VFS_H

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/* plan9 semantics are that created files are implicitly opened.

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 * But linux semantics are that you call create, then open.

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 * the plan9 approach is superior as it provides an atomic

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 * open.

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 * we track the create fid here. When the file is opened, if fidopen is

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 * non-zero, we use the fid and can skip some steps.

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 * there may be a better way to do this, but I don't know it.

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 * one BAD way is to clunk the fid on create, then open it again:

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 * you lose the atomicity of file open

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 */

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/* special case:

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 * unlink calls remove, which is an implicit clunk. So we have to track

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 * that kind of thing so that we don't try to clunk a dead fid.

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 */

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#define P9_LOCK_TIMEOUT (30*HZ)

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/* flags for v9fs_stat2inode() & v9fs_stat2inode_dotl() */

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#define V9FS_STAT2INODE_KEEP_ISIZE 1

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extern struct file_system_type v9fs_fs_type;

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extern const struct address_space_operations v9fs_addr_operations;

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extern const struct file_operations v9fs_file_operations;

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extern const struct file_operations v9fs_file_operations_dotl;

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extern const struct file_operations v9fs_dir_operations;

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extern const struct file_operations v9fs_dir_operations_dotl;

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extern const struct dentry_operations v9fs_dentry_operations;

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extern const struct dentry_operations v9fs_cached_dentry_operations;

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extern struct kmem_cache *v9fs_inode_cache;

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struct inode *v9fs_alloc_inode(struct super_block *sb);

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void v9fs_free_inode(struct inode *inode);

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void v9fs_set_netfs_context(struct inode *inode);

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int v9fs_init_inode(struct v9fs_session_info *v9ses,

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		    struct inode *inode, umode_t mode, dev_t rdev);

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void v9fs_evict_inode(struct inode *inode);

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#if (BITS_PER_LONG == 32)

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#define QID2INO(q) ((ino_t) (((q)->path+2) ^ (((q)->path) >> 32)))

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#else

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#define QID2INO(q) ((ino_t) ((q)->path+2))

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#endif

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void v9fs_stat2inode(struct p9_wstat *stat, struct inode *inode,

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		      struct super_block *sb, unsigned int flags);

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void v9fs_stat2inode_dotl(struct p9_stat_dotl *stat, struct inode *inode,

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			   unsigned int flags);

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int v9fs_dir_release(struct inode *inode, struct file *filp);

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int v9fs_file_open(struct inode *inode, struct file *file);

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int v9fs_uflags2omode(int uflags, int extended);

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void v9fs_blank_wstat(struct p9_wstat *wstat);

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int v9fs_vfs_setattr_dotl(struct mnt_idmap *idmap,

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			  struct dentry *dentry, struct iattr *iattr);

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int v9fs_file_fsync_dotl(struct file *filp, loff_t start, loff_t end,

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			 int datasync);

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int v9fs_refresh_inode(struct p9_fid *fid, struct inode *inode);

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int v9fs_refresh_inode_dotl(struct p9_fid *fid, struct inode *inode);

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static inline void v9fs_invalidate_inode_attr(struct inode *inode)

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{

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	struct v9fs_inode *v9inode;

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	v9inode = V9FS_I(inode);

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	v9inode->cache_validity |= V9FS_INO_INVALID_ATTR;

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}

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int v9fs_open_to_dotl_flags(int flags);

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static inline void v9fs_i_size_write(struct inode *inode, loff_t i_size)

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{

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	/*

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	 * 32-bit need the lock, concurrent updates could break the

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	 * sequences and make i_size_read() loop forever.

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	 * 64-bit updates are atomic and can skip the locking.

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	 */

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	if (sizeof(i_size) > sizeof(long))

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		spin_lock(&inode->i_lock);

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	i_size_write(inode, i_size);

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	if (sizeof(i_size) > sizeof(long))

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		spin_unlock(&inode->i_lock);

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}

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#endif

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