include/linux/nfs_fs.h - LeafOS-Devices/android_kernel_samsung_gta4xl - Gitiles

 /*
  *  linux/include/linux/nfs_fs.h
  *
  *  Copyright (C) 1992  Rick Sladkey
  *
  *  OS-specific nfs filesystem definitions and declarations
  */

 #ifndef _LINUX_NFS_FS_H
 #define _LINUX_NFS_FS_H

 #include <linux/magic.h>

 /*
  * Enable debugging support for nfs client.
  * Requires RPC_DEBUG.
  */
 #ifdef RPC_DEBUG
 # define NFS_DEBUG
 #endif

 /* Default timeout values */
 #define NFS_MAX_UDP_TIMEOUT	(60*HZ)
 #define NFS_MAX_TCP_TIMEOUT	(600*HZ)

 /*
  * When flushing a cluster of dirty pages, there can be different
  * strategies:
  */
 #define FLUSH_SYNC		1	/* file being synced, or contention */
 #define FLUSH_STABLE		4	/* commit to stable storage */
 #define FLUSH_LOWPRI		8	/* low priority background flush */
 #define FLUSH_HIGHPRI		16	/* high priority memory reclaim flush */
 #define FLUSH_NOCOMMIT		32	/* Don't send the NFSv3/v4 COMMIT */
 #define FLUSH_INVALIDATE	64	/* Invalidate the page cache */
 #define FLUSH_NOWRITEPAGE	128	/* Don't call writepage() */

 #ifdef __KERNEL__

 #include <linux/in.h>
 #include <linux/mm.h>
 #include <linux/pagemap.h>
 #include <linux/rbtree.h>
 #include <linux/rwsem.h>
 #include <linux/wait.h>

 #include <linux/sunrpc/debug.h>
 #include <linux/sunrpc/auth.h>
 #include <linux/sunrpc/clnt.h>

 #include <linux/nfs.h>
 #include <linux/nfs2.h>
 #include <linux/nfs3.h>
 #include <linux/nfs4.h>
 #include <linux/nfs_xdr.h>

 #include <linux/nfs_fs_sb.h>

 #include <linux/rwsem.h>
 #include <linux/mempool.h>

 /*
  * These are the default flags for swap requests
  */
 #define NFS_RPC_SWAPFLAGS		(RPC_TASK_SWAPPER|RPC_TASK_ROOTCREDS)

 /*
  * NFSv3/v4 Access mode cache entry
  */
 struct nfs_access_entry {
 	struct rb_node		rb_node;
 	struct list_head	lru;
 	unsigned long		jiffies;
 	struct rpc_cred *	cred;
 	int			mask;
 };

 struct nfs4_state;
 struct nfs_open_context {
 	atomic_t count;
 	struct vfsmount *vfsmnt;
 	struct dentry *dentry;
 	struct rpc_cred *cred;
 	struct nfs4_state *state;
 	fl_owner_t lockowner;
 	int mode;
 	int error;

 	struct list_head list;

 	__u64 dir_cookie;
 };

 /*
  * NFSv4 delegation
  */
 struct nfs_delegation;

 struct posix_acl;

 /*
  * nfs fs inode data in memory
  */
 struct nfs_inode {
 	/*
 	 * The 64bit 'inode number'
 	 */
 	__u64 fileid;

 	/*
 	 * NFS file handle
 	 */
 	struct nfs_fh		fh;

 	/*
 	 * Various flags
 	 */
 	unsigned long		flags;			/* atomic bit ops */
 	unsigned long		cache_validity;		/* bit mask */

 	/*
 	 * read_cache_jiffies is when we started read-caching this inode.
 	 * attrtimeo is for how long the cached information is assumed
 	 * to be valid. A successful attribute revalidation doubles
 	 * attrtimeo (up to acregmax/acdirmax), a failure resets it to
 	 * acregmin/acdirmin.
 	 *
 	 * We need to revalidate the cached attrs for this inode if
 	 *
 	 *	jiffies - read_cache_jiffies > attrtimeo
 	 */
 	unsigned long		read_cache_jiffies;
 	unsigned long		attrtimeo;
 	unsigned long		attrtimeo_timestamp;
 	__u64			change_attr;		/* v4 only */

 	unsigned long		last_updated;
 	/* "Generation counter" for the attribute cache. This is
 	 * bumped whenever we update the metadata on the
 	 * server.
 	 */
 	unsigned long		cache_change_attribute;
 	/*
 	 * Counter indicating the number of outstanding requests that
 	 * will cause a file data update.
 	 */
 	atomic_t		data_updates;

 	struct rb_root		access_cache;
 	struct list_head	access_cache_entry_lru;
 	struct list_head	access_cache_inode_lru;
 #ifdef CONFIG_NFS_V3_ACL
 	struct posix_acl	*acl_access;
 	struct posix_acl	*acl_default;
 #endif

 	/*
 	 * This is the cookie verifier used for NFSv3 readdir
 	 * operations
 	 */
 	__be32			cookieverf[2];

 	/*
 	 * This is the list of dirty unwritten pages.
 	 */
 	spinlock_t		req_lock;
 	struct list_head	dirty;
 	struct list_head	commit;
 	struct radix_tree_root	nfs_page_tree;

 	unsigned int		ndirty,
 				ncommit,
 				npages;

 	/* Open contexts for shared mmap writes */
 	struct list_head	open_files;

 #ifdef CONFIG_NFS_V4
 	struct nfs4_cached_acl	*nfs4_acl;
         /* NFSv4 state */
 	struct list_head	open_states;
 	struct nfs_delegation	*delegation;
 	int			 delegation_state;
 	struct rw_semaphore	rwsem;
 #endif /* CONFIG_NFS_V4*/
 	struct inode		vfs_inode;
 };

 /*
  * Cache validity bit flags
  */
 #define NFS_INO_INVALID_ATTR	0x0001		/* cached attrs are invalid */
 #define NFS_INO_INVALID_DATA	0x0002		/* cached data is invalid */
 #define NFS_INO_INVALID_ATIME	0x0004		/* cached atime is invalid */
 #define NFS_INO_INVALID_ACCESS	0x0008		/* cached access cred invalid */
 #define NFS_INO_INVALID_ACL	0x0010		/* cached acls are invalid */
 #define NFS_INO_REVAL_PAGECACHE	0x0020		/* must revalidate pagecache */

 /*
  * Bit offsets in flags field
  */
 #define NFS_INO_REVALIDATING	(0)		/* revalidating attrs */
 #define NFS_INO_ADVISE_RDPLUS	(1)		/* advise readdirplus */
 #define NFS_INO_STALE		(2)		/* possible stale inode */
 #define NFS_INO_ACL_LRU_SET	(3)		/* Inode is on the LRU list */

 static inline struct nfs_inode *NFS_I(struct inode *inode)
 {
 	return container_of(inode, struct nfs_inode, vfs_inode);
 }
 #define NFS_SB(s)		((struct nfs_server *)(s->s_fs_info))

 #define NFS_FH(inode)			(&NFS_I(inode)->fh)
 #define NFS_SERVER(inode)		(NFS_SB(inode->i_sb))
 #define NFS_CLIENT(inode)		(NFS_SERVER(inode)->client)
 #define NFS_PROTO(inode)		(NFS_SERVER(inode)->nfs_client->rpc_ops)
 #define NFS_COOKIEVERF(inode)		(NFS_I(inode)->cookieverf)
 #define NFS_READTIME(inode)		(NFS_I(inode)->read_cache_jiffies)
 #define NFS_CHANGE_ATTR(inode)		(NFS_I(inode)->change_attr)
 #define NFS_ATTRTIMEO(inode)		(NFS_I(inode)->attrtimeo)
 #define NFS_MINATTRTIMEO(inode) \
 	(S_ISDIR(inode->i_mode)? NFS_SERVER(inode)->acdirmin \
 			       : NFS_SERVER(inode)->acregmin)
 #define NFS_MAXATTRTIMEO(inode) \
 	(S_ISDIR(inode->i_mode)? NFS_SERVER(inode)->acdirmax \
 			       : NFS_SERVER(inode)->acregmax)
 #define NFS_ATTRTIMEO_UPDATE(inode)	(NFS_I(inode)->attrtimeo_timestamp)

 #define NFS_FLAGS(inode)		(NFS_I(inode)->flags)
 #define NFS_STALE(inode)		(test_bit(NFS_INO_STALE, &NFS_FLAGS(inode)))

 #define NFS_FILEID(inode)		(NFS_I(inode)->fileid)

 static inline int nfs_caches_unstable(struct inode *inode)
 {
 	return atomic_read(&NFS_I(inode)->data_updates) != 0;
 }

 static inline void nfs_mark_for_revalidate(struct inode *inode)
 {
 	struct nfs_inode *nfsi = NFS_I(inode);

 	spin_lock(&inode->i_lock);
 	nfsi->cache_validity |= NFS_INO_INVALID_ATTR|NFS_INO_INVALID_ACCESS;
 	if (S_ISDIR(inode->i_mode))
 		nfsi->cache_validity |= NFS_INO_REVAL_PAGECACHE|NFS_INO_INVALID_DATA;
 	spin_unlock(&inode->i_lock);
 }

 static inline void NFS_CACHEINV(struct inode *inode)
 {
 	if (!nfs_caches_unstable(inode))
 		nfs_mark_for_revalidate(inode);
 }

 static inline int nfs_server_capable(struct inode *inode, int cap)
 {
 	return NFS_SERVER(inode)->caps & cap;
 }

 static inline int NFS_USE_READDIRPLUS(struct inode *inode)
 {
 	return test_bit(NFS_INO_ADVISE_RDPLUS, &NFS_FLAGS(inode));
 }

 /**
  * nfs_save_change_attribute - Returns the inode attribute change cookie
  * @inode - pointer to inode
  * The "change attribute" is updated every time we finish an operation
  * that will result in a metadata change on the server.
  */
 static inline long nfs_save_change_attribute(struct inode *inode)
 {
 	return NFS_I(inode)->cache_change_attribute;
 }

 /**
  * nfs_verify_change_attribute - Detects NFS inode cache updates
  * @inode - pointer to inode
  * @chattr - previously saved change attribute
  * Return "false" if metadata has been updated (or is in the process of
  * being updated) since the change attribute was saved.
  */
 static inline int nfs_verify_change_attribute(struct inode *inode, unsigned long chattr)
 {
 	return !nfs_caches_unstable(inode)
 		&& time_after_eq(chattr, NFS_I(inode)->cache_change_attribute);
 }

 /*
  * linux/fs/nfs/inode.c
  */
 extern int nfs_sync_mapping(struct address_space *mapping);
 extern void nfs_zap_mapping(struct inode *inode, struct address_space *mapping);
 extern void nfs_zap_caches(struct inode *);
 extern struct inode *nfs_fhget(struct super_block *, struct nfs_fh *,
 				struct nfs_fattr *);
 extern int nfs_refresh_inode(struct inode *, struct nfs_fattr *);
 extern int nfs_post_op_update_inode(struct inode *inode, struct nfs_fattr *fattr);
 extern int nfs_getattr(struct vfsmount *, struct dentry *, struct kstat *);
 extern int nfs_permission(struct inode *, int, struct nameidata *);
 extern int nfs_access_get_cached(struct inode *, struct rpc_cred *, struct nfs_access_entry *);
 extern void nfs_access_add_cache(struct inode *, struct nfs_access_entry *);
 extern void nfs_access_zap_cache(struct inode *inode);
 extern int nfs_open(struct inode *, struct file *);
 extern int nfs_release(struct inode *, struct file *);
 extern int nfs_attribute_timeout(struct inode *inode);
 extern int nfs_revalidate_inode(struct nfs_server *server, struct inode *inode);
 extern int __nfs_revalidate_inode(struct nfs_server *, struct inode *);
 extern int nfs_revalidate_mapping(struct inode *inode, struct address_space *mapping);
 extern int nfs_revalidate_mapping_nolock(struct inode *inode, struct address_space *mapping);
 extern int nfs_setattr(struct dentry *, struct iattr *);
 extern void nfs_setattr_update_inode(struct inode *inode, struct iattr *attr);
 extern void nfs_begin_attr_update(struct inode *);
 extern void nfs_end_attr_update(struct inode *);
 extern void nfs_begin_data_update(struct inode *);
 extern void nfs_end_data_update(struct inode *);
 extern struct nfs_open_context *get_nfs_open_context(struct nfs_open_context *ctx);
 extern void put_nfs_open_context(struct nfs_open_context *ctx);
 extern struct nfs_open_context *nfs_find_open_context(struct inode *inode, struct rpc_cred *cred, int mode);

 /* linux/net/ipv4/ipconfig.c: trims ip addr off front of name, too. */
 extern __be32 root_nfs_parse_addr(char *name); /*__init*/

 static inline void nfs_fattr_init(struct nfs_fattr *fattr)
 {
 	fattr->valid = 0;
 	fattr->time_start = jiffies;
 }

 /*
  * linux/fs/nfs/file.c
  */
 extern const struct inode_operations nfs_file_inode_operations;
 #ifdef CONFIG_NFS_V3
 extern const struct inode_operations nfs3_file_inode_operations;
 #endif /* CONFIG_NFS_V3 */
 extern const struct file_operations nfs_file_operations;
 extern const struct address_space_operations nfs_file_aops;

 static inline struct rpc_cred *nfs_file_cred(struct file *file)
 {
 	if (file != NULL) {
 		struct nfs_open_context *ctx;

 		ctx = (struct nfs_open_context*)file->private_data;
 		return ctx->cred;
 	}
 	return NULL;
 }

 /*
  * linux/fs/nfs/xattr.c
  */
 #ifdef CONFIG_NFS_V3_ACL
 extern ssize_t nfs3_listxattr(struct dentry *, char *, size_t);
 extern ssize_t nfs3_getxattr(struct dentry *, const char *, void *, size_t);
 extern int nfs3_setxattr(struct dentry *, const char *,
 			const void *, size_t, int);
 extern int nfs3_removexattr (struct dentry *, const char *name);
 #else
 # define nfs3_listxattr NULL
 # define nfs3_getxattr NULL
 # define nfs3_setxattr NULL
 # define nfs3_removexattr NULL
 #endif

 /*
  * linux/fs/nfs/direct.c
  */
 extern ssize_t nfs_direct_IO(int, struct kiocb *, const struct iovec *, loff_t,
 			unsigned long);
 extern ssize_t nfs_file_direct_read(struct kiocb *iocb,
 			const struct iovec *iov, unsigned long nr_segs,
 			loff_t pos);
 extern ssize_t nfs_file_direct_write(struct kiocb *iocb,
 			const struct iovec *iov, unsigned long nr_segs,
 			loff_t pos);

 /*
  * linux/fs/nfs/dir.c
  */
 extern const struct inode_operations nfs_dir_inode_operations;
 #ifdef CONFIG_NFS_V3
 extern const struct inode_operations nfs3_dir_inode_operations;
 #endif /* CONFIG_NFS_V3 */
 extern const struct file_operations nfs_dir_operations;
 extern struct dentry_operations nfs_dentry_operations;

 extern int nfs_instantiate(struct dentry *dentry, struct nfs_fh *fh, struct nfs_fattr *fattr);

 /*
  * linux/fs/nfs/symlink.c
  */
 extern const struct inode_operations nfs_symlink_inode_operations;

 /*
  * linux/fs/nfs/sysctl.c
  */
 #ifdef CONFIG_SYSCTL
 extern int nfs_register_sysctl(void);
 extern void nfs_unregister_sysctl(void);
 #else
 #define nfs_register_sysctl() 0
 #define nfs_unregister_sysctl() do { } while(0)
 #endif

 /*
  * linux/fs/nfs/namespace.c
  */
 extern struct list_head nfs_automount_list;
 extern const struct inode_operations nfs_mountpoint_inode_operations;
 extern const struct inode_operations nfs_referral_inode_operations;
 extern int nfs_mountpoint_expiry_timeout;
 extern void nfs_release_automount_timer(void);

 /*
  * linux/fs/nfs/unlink.c
  */
 extern int  nfs_async_unlink(struct dentry *);
 extern void nfs_complete_unlink(struct dentry *);

 /*
  * linux/fs/nfs/write.c
  */
 extern int  nfs_writepage(struct page *page, struct writeback_control *wbc);
 extern int  nfs_writepages(struct address_space *, struct writeback_control *);
 extern int  nfs_flush_incompatible(struct file *file, struct page *page);
 extern int  nfs_updatepage(struct file *, struct page *, unsigned int, unsigned int);
 extern int nfs_writeback_done(struct rpc_task *, struct nfs_write_data *);
 extern void nfs_writedata_release(void *);
 extern int nfs_set_page_dirty(struct page *);

 /*
  * Try to write back everything synchronously (but check the
  * return value!)
  */
 extern long nfs_sync_mapping_wait(struct address_space *, struct writeback_control *, int);
 extern int nfs_sync_mapping_range(struct address_space *, loff_t, loff_t, int);
 extern int nfs_wb_all(struct inode *inode);
 extern int nfs_wb_page(struct inode *inode, struct page* page);
 extern int nfs_wb_page_priority(struct inode *inode, struct page* page, int how);
 #if defined(CONFIG_NFS_V3) || defined(CONFIG_NFS_V4)
 extern int  nfs_commit_inode(struct inode *, int);
 extern struct nfs_write_data *nfs_commit_alloc(void);
 extern void nfs_commit_free(struct nfs_write_data *wdata);
 extern void nfs_commit_release(void *wdata);
 #else
 static inline int
 nfs_commit_inode(struct inode *inode, int how)
 {
 	return 0;
 }
 #endif

 static inline int
 nfs_have_writebacks(struct inode *inode)
 {
 	return NFS_I(inode)->npages != 0;
 }

 /*
  * Allocate nfs_write_data structures
  */
 extern struct nfs_write_data *nfs_writedata_alloc(size_t len);

 /*
  * linux/fs/nfs/read.c
  */
 extern int  nfs_readpage(struct file *, struct page *);
 extern int  nfs_readpages(struct file *, struct address_space *,
 		struct list_head *, unsigned);
 extern int  nfs_readpage_result(struct rpc_task *, struct nfs_read_data *);
 extern void nfs_readdata_release(void *data);

 /*
  * Allocate nfs_read_data structures
  */
 extern struct nfs_read_data *nfs_readdata_alloc(size_t len);

 /*
  * linux/fs/nfs3proc.c
  */
 #ifdef CONFIG_NFS_V3_ACL
 extern struct posix_acl *nfs3_proc_getacl(struct inode *inode, int type);
 extern int nfs3_proc_setacl(struct inode *inode, int type,
 			    struct posix_acl *acl);
 extern int nfs3_proc_set_default_acl(struct inode *dir, struct inode *inode,
 		mode_t mode);
 extern void nfs3_forget_cached_acls(struct inode *inode);
 #else
 static inline int nfs3_proc_set_default_acl(struct inode *dir,
 					    struct inode *inode,
 					    mode_t mode)
 {
 	return 0;
 }

 static inline void nfs3_forget_cached_acls(struct inode *inode)
 {
 }
 #endif /* CONFIG_NFS_V3_ACL */

 /*
  * linux/fs/mount_clnt.c
  * (Used only by nfsroot module)
  */
 extern int  nfsroot_mount(struct sockaddr_in *, char *, struct nfs_fh *,
 		int, int);

 /*
  * inline functions
  */

 static inline loff_t
 nfs_size_to_loff_t(__u64 size)
 {
 	loff_t maxsz = (((loff_t) ULONG_MAX) << PAGE_CACHE_SHIFT) + PAGE_CACHE_SIZE - 1;
 	if (size > maxsz)
 		return maxsz;
 	return (loff_t) size;
 }

 static inline ino_t
 nfs_fileid_to_ino_t(u64 fileid)
 {
 	ino_t ino = (ino_t) fileid;
 	if (sizeof(ino_t) < sizeof(u64))
 		ino ^= fileid >> (sizeof(u64)-sizeof(ino_t)) * 8;
 	return ino;
 }

 /* NFS root */

 extern void * nfs_root_data(void);

 #define nfs_wait_event(clnt, wq, condition)				\
 ({									\
 	int __retval = 0;						\
 	if (clnt->cl_intr) {						\
 		sigset_t oldmask;					\
 		rpc_clnt_sigmask(clnt, &oldmask);			\
 		__retval = wait_event_interruptible(wq, condition);	\
 		rpc_clnt_sigunmask(clnt, &oldmask);			\
 	} else								\
 		wait_event(wq, condition);				\
 	__retval;							\
 })

 #define NFS_JUKEBOX_RETRY_TIME (5 * HZ)

 #endif /* __KERNEL__ */

 /*
  * NFS debug flags
  */
 #define NFSDBG_VFS		0x0001
 #define NFSDBG_DIRCACHE		0x0002
 #define NFSDBG_LOOKUPCACHE	0x0004
 #define NFSDBG_PAGECACHE	0x0008
 #define NFSDBG_PROC		0x0010
 #define NFSDBG_XDR		0x0020
 #define NFSDBG_FILE		0x0040
 #define NFSDBG_ROOT		0x0080
 #define NFSDBG_CALLBACK		0x0100
 #define NFSDBG_CLIENT		0x0200
 #define NFSDBG_ALL		0xFFFF

 #ifdef __KERNEL__
 # undef ifdebug
 # ifdef NFS_DEBUG
 #  define ifdebug(fac)		if (unlikely(nfs_debug & NFSDBG_##fac))
 # else
 #  define ifdebug(fac)		if (0)
 # endif
 #endif /* __KERNEL */

 #endif
	/*
	* linux/include/linux/nfs_fs.h
	*
	* Copyright (C) 1992 Rick Sladkey
	*
	* OS-specific nfs filesystem definitions and declarations
	*/

	#ifndef _LINUX_NFS_FS_H
	#define _LINUX_NFS_FS_H

	#include <linux/magic.h>

	/*
	* Enable debugging support for nfs client.
	* Requires RPC_DEBUG.
	*/
	#ifdef RPC_DEBUG
	# define NFS_DEBUG
	#endif

	/* Default timeout values */
	#define NFS_MAX_UDP_TIMEOUT (60*HZ)
	#define NFS_MAX_TCP_TIMEOUT (600*HZ)

	/*
	* When flushing a cluster of dirty pages, there can be different
	* strategies:
	*/
	#define FLUSH_SYNC 1 /* file being synced, or contention */
	#define FLUSH_STABLE 4 /* commit to stable storage */
	#define FLUSH_LOWPRI 8 /* low priority background flush */
	#define FLUSH_HIGHPRI 16 /* high priority memory reclaim flush */
	#define FLUSH_NOCOMMIT 32 /* Don't send the NFSv3/v4 COMMIT */
	#define FLUSH_INVALIDATE 64 /* Invalidate the page cache */
	#define FLUSH_NOWRITEPAGE 128 /* Don't call writepage() */

	#ifdef __KERNEL__

	#include <linux/in.h>
	#include <linux/mm.h>
	#include <linux/pagemap.h>
	#include <linux/rbtree.h>
	#include <linux/rwsem.h>
	#include <linux/wait.h>

	#include <linux/sunrpc/debug.h>
	#include <linux/sunrpc/auth.h>
	#include <linux/sunrpc/clnt.h>

	#include <linux/nfs.h>
	#include <linux/nfs2.h>
	#include <linux/nfs3.h>
	#include <linux/nfs4.h>
	#include <linux/nfs_xdr.h>

	#include <linux/nfs_fs_sb.h>

	#include <linux/rwsem.h>
	#include <linux/mempool.h>

	/*
	* These are the default flags for swap requests
	*/
	#define NFS_RPC_SWAPFLAGS (RPC_TASK_SWAPPER\|RPC_TASK_ROOTCREDS)

	/*
	* NFSv3/v4 Access mode cache entry
	*/
	struct nfs_access_entry {
	struct rb_node rb_node;
	struct list_head lru;
	unsigned long jiffies;
	struct rpc_cred * cred;
	int mask;
	};

	struct nfs4_state;
	struct nfs_open_context {
	atomic_t count;
	struct vfsmount *vfsmnt;
	struct dentry *dentry;
	struct rpc_cred *cred;
	struct nfs4_state *state;
	fl_owner_t lockowner;
	int mode;
	int error;

	struct list_head list;

	__u64 dir_cookie;
	};

	/*
	* NFSv4 delegation
	*/
	struct nfs_delegation;

	struct posix_acl;

	/*
	* nfs fs inode data in memory
	*/
	struct nfs_inode {
	/*
	* The 64bit 'inode number'
	*/
	__u64 fileid;

	/*
	* NFS file handle
	*/
	struct nfs_fh fh;

	/*
	* Various flags
	*/
	unsigned long flags; /* atomic bit ops */
	unsigned long cache_validity; /* bit mask */

	/*
	* read_cache_jiffies is when we started read-caching this inode.
	* attrtimeo is for how long the cached information is assumed
	* to be valid. A successful attribute revalidation doubles
	* attrtimeo (up to acregmax/acdirmax), a failure resets it to
	* acregmin/acdirmin.
	*
	* We need to revalidate the cached attrs for this inode if
	*
	* jiffies - read_cache_jiffies > attrtimeo
	*/
	unsigned long read_cache_jiffies;
	unsigned long attrtimeo;
	unsigned long attrtimeo_timestamp;
	__u64 change_attr; /* v4 only */

	unsigned long last_updated;
	/* "Generation counter" for the attribute cache. This is
	* bumped whenever we update the metadata on the
	* server.
	*/
	unsigned long cache_change_attribute;
	/*
	* Counter indicating the number of outstanding requests that
	* will cause a file data update.
	*/
	atomic_t data_updates;

	struct rb_root access_cache;
	struct list_head access_cache_entry_lru;
	struct list_head access_cache_inode_lru;
	#ifdef CONFIG_NFS_V3_ACL
	struct posix_acl *acl_access;
	struct posix_acl *acl_default;
	#endif

	/*
	* This is the cookie verifier used for NFSv3 readdir
	* operations
	*/
	__be32 cookieverf[2];

	/*
	* This is the list of dirty unwritten pages.
	*/
	spinlock_t req_lock;
	struct list_head dirty;
	struct list_head commit;
	struct radix_tree_root nfs_page_tree;

	unsigned int ndirty,
	ncommit,
	npages;

	/* Open contexts for shared mmap writes */
	struct list_head open_files;

	#ifdef CONFIG_NFS_V4
	struct nfs4_cached_acl *nfs4_acl;
	/* NFSv4 state */
	struct list_head open_states;
	struct nfs_delegation *delegation;
	int delegation_state;
	struct rw_semaphore rwsem;
	#endif /* CONFIG_NFS_V4*/
	struct inode vfs_inode;
	};

	/*
	* Cache validity bit flags
	*/
	#define NFS_INO_INVALID_ATTR 0x0001 /* cached attrs are invalid */
	#define NFS_INO_INVALID_DATA 0x0002 /* cached data is invalid */
	#define NFS_INO_INVALID_ATIME 0x0004 /* cached atime is invalid */
	#define NFS_INO_INVALID_ACCESS 0x0008 /* cached access cred invalid */
	#define NFS_INO_INVALID_ACL 0x0010 /* cached acls are invalid */
	#define NFS_INO_REVAL_PAGECACHE 0x0020 /* must revalidate pagecache */

	/*
	* Bit offsets in flags field
	*/
	#define NFS_INO_REVALIDATING (0) /* revalidating attrs */
	#define NFS_INO_ADVISE_RDPLUS (1) /* advise readdirplus */
	#define NFS_INO_STALE (2) /* possible stale inode */
	#define NFS_INO_ACL_LRU_SET (3) /* Inode is on the LRU list */

	static inline struct nfs_inode NFS_I(struct inode inode)
	{
	return container_of(inode, struct nfs_inode, vfs_inode);
	}
	#define NFS_SB(s) ((struct nfs_server *)(s->s_fs_info))

	#define NFS_FH(inode) (&NFS_I(inode)->fh)
	#define NFS_SERVER(inode) (NFS_SB(inode->i_sb))
	#define NFS_CLIENT(inode) (NFS_SERVER(inode)->client)
	#define NFS_PROTO(inode) (NFS_SERVER(inode)->nfs_client->rpc_ops)
	#define NFS_COOKIEVERF(inode) (NFS_I(inode)->cookieverf)
	#define NFS_READTIME(inode) (NFS_I(inode)->read_cache_jiffies)
	#define NFS_CHANGE_ATTR(inode) (NFS_I(inode)->change_attr)
	#define NFS_ATTRTIMEO(inode) (NFS_I(inode)->attrtimeo)
	#define NFS_MINATTRTIMEO(inode) \
	(S_ISDIR(inode->i_mode)? NFS_SERVER(inode)->acdirmin \
	: NFS_SERVER(inode)->acregmin)
	#define NFS_MAXATTRTIMEO(inode) \
	(S_ISDIR(inode->i_mode)? NFS_SERVER(inode)->acdirmax \
	: NFS_SERVER(inode)->acregmax)
	#define NFS_ATTRTIMEO_UPDATE(inode) (NFS_I(inode)->attrtimeo_timestamp)

	#define NFS_FLAGS(inode) (NFS_I(inode)->flags)
	#define NFS_STALE(inode) (test_bit(NFS_INO_STALE, &NFS_FLAGS(inode)))

	#define NFS_FILEID(inode) (NFS_I(inode)->fileid)

	static inline int nfs_caches_unstable(struct inode *inode)
	{
	return atomic_read(&NFS_I(inode)->data_updates) != 0;
	}

	static inline void nfs_mark_for_revalidate(struct inode *inode)
	{
	struct nfs_inode *nfsi = NFS_I(inode);

	spin_lock(&inode->i_lock);
	nfsi->cache_validity \|= NFS_INO_INVALID_ATTR\|NFS_INO_INVALID_ACCESS;
	if (S_ISDIR(inode->i_mode))
	nfsi->cache_validity \|= NFS_INO_REVAL_PAGECACHE\|NFS_INO_INVALID_DATA;
	spin_unlock(&inode->i_lock);
	}

	static inline void NFS_CACHEINV(struct inode *inode)
	{
	if (!nfs_caches_unstable(inode))
	nfs_mark_for_revalidate(inode);
	}

	static inline int nfs_server_capable(struct inode *inode, int cap)
	{
	return NFS_SERVER(inode)->caps & cap;
	}

	static inline int NFS_USE_READDIRPLUS(struct inode *inode)
	{
	return test_bit(NFS_INO_ADVISE_RDPLUS, &NFS_FLAGS(inode));
	}

	/**
	* nfs_save_change_attribute - Returns the inode attribute change cookie
	* @inode - pointer to inode
	* The "change attribute" is updated every time we finish an operation
	* that will result in a metadata change on the server.
	*/
	static inline long nfs_save_change_attribute(struct inode *inode)
	{
	return NFS_I(inode)->cache_change_attribute;
	}

	/**
	* nfs_verify_change_attribute - Detects NFS inode cache updates
	* @inode - pointer to inode
	* @chattr - previously saved change attribute
	* Return "false" if metadata has been updated (or is in the process of
	* being updated) since the change attribute was saved.
	*/
	static inline int nfs_verify_change_attribute(struct inode *inode, unsigned long chattr)
	{
	return !nfs_caches_unstable(inode)
	&& time_after_eq(chattr, NFS_I(inode)->cache_change_attribute);
	}

	/*
	* linux/fs/nfs/inode.c
	*/
	extern int nfs_sync_mapping(struct address_space *mapping);
	extern void nfs_zap_mapping(struct inode inode, struct address_space mapping);
	extern void nfs_zap_caches(struct inode *);
	extern struct inode nfs_fhget(struct super_block , struct nfs_fh *,
	struct nfs_fattr *);
	extern int nfs_refresh_inode(struct inode , struct nfs_fattr );
	extern int nfs_post_op_update_inode(struct inode inode, struct nfs_fattr fattr);
	extern int nfs_getattr(struct vfsmount , struct dentry , struct kstat *);
	extern int nfs_permission(struct inode , int, struct nameidata );
	extern int nfs_access_get_cached(struct inode , struct rpc_cred , struct nfs_access_entry *);
	extern void nfs_access_add_cache(struct inode , struct nfs_access_entry );
	extern void nfs_access_zap_cache(struct inode *inode);
	extern int nfs_open(struct inode , struct file );
	extern int nfs_release(struct inode , struct file );
	extern int nfs_attribute_timeout(struct inode *inode);
	extern int nfs_revalidate_inode(struct nfs_server server, struct inode inode);
	extern int __nfs_revalidate_inode(struct nfs_server , struct inode );
	extern int nfs_revalidate_mapping(struct inode inode, struct address_space mapping);
	extern int nfs_revalidate_mapping_nolock(struct inode inode, struct address_space mapping);
	extern int nfs_setattr(struct dentry , struct iattr );
	extern void nfs_setattr_update_inode(struct inode inode, struct iattr attr);
	extern void nfs_begin_attr_update(struct inode *);
	extern void nfs_end_attr_update(struct inode *);
	extern void nfs_begin_data_update(struct inode *);
	extern void nfs_end_data_update(struct inode *);
	extern struct nfs_open_context get_nfs_open_context(struct nfs_open_context ctx);
	extern void put_nfs_open_context(struct nfs_open_context *ctx);
	extern struct nfs_open_context nfs_find_open_context(struct inode inode, struct rpc_cred *cred, int mode);

	/* linux/net/ipv4/ipconfig.c: trims ip addr off front of name, too. */
	extern __be32 root_nfs_parse_addr(char name); /__init*/

	static inline void nfs_fattr_init(struct nfs_fattr *fattr)
	{
	fattr->valid = 0;
	fattr->time_start = jiffies;
	}

	/*
	* linux/fs/nfs/file.c
	*/
	extern const struct inode_operations nfs_file_inode_operations;
	#ifdef CONFIG_NFS_V3
	extern const struct inode_operations nfs3_file_inode_operations;
	#endif /* CONFIG_NFS_V3 */
	extern const struct file_operations nfs_file_operations;
	extern const struct address_space_operations nfs_file_aops;

	static inline struct rpc_cred nfs_file_cred(struct file file)
	{
	if (file != NULL) {
	struct nfs_open_context *ctx;

	ctx = (struct nfs_open_context*)file->private_data;
	return ctx->cred;
	}
	return NULL;
	}

	/*
	* linux/fs/nfs/xattr.c
	*/
	#ifdef CONFIG_NFS_V3_ACL
	extern ssize_t nfs3_listxattr(struct dentry , char , size_t);
	extern ssize_t nfs3_getxattr(struct dentry , const char , void *, size_t);
	extern int nfs3_setxattr(struct dentry , const char ,
	const void *, size_t, int);
	extern int nfs3_removexattr (struct dentry , const char name);
	#else
	# define nfs3_listxattr NULL
	# define nfs3_getxattr NULL
	# define nfs3_setxattr NULL
	# define nfs3_removexattr NULL
	#endif

	/*
	* linux/fs/nfs/direct.c
	*/
	extern ssize_t nfs_direct_IO(int, struct kiocb , const struct iovec , loff_t,
	unsigned long);
	extern ssize_t nfs_file_direct_read(struct kiocb *iocb,
	const struct iovec *iov, unsigned long nr_segs,
	loff_t pos);
	extern ssize_t nfs_file_direct_write(struct kiocb *iocb,
	const struct iovec *iov, unsigned long nr_segs,
	loff_t pos);

	/*
	* linux/fs/nfs/dir.c
	*/
	extern const struct inode_operations nfs_dir_inode_operations;
	#ifdef CONFIG_NFS_V3
	extern const struct inode_operations nfs3_dir_inode_operations;
	#endif /* CONFIG_NFS_V3 */
	extern const struct file_operations nfs_dir_operations;
	extern struct dentry_operations nfs_dentry_operations;

	extern int nfs_instantiate(struct dentry dentry, struct nfs_fh fh, struct nfs_fattr *fattr);

	/*
	* linux/fs/nfs/symlink.c
	*/
	extern const struct inode_operations nfs_symlink_inode_operations;

	/*
	* linux/fs/nfs/sysctl.c
	*/
	#ifdef CONFIG_SYSCTL
	extern int nfs_register_sysctl(void);
	extern void nfs_unregister_sysctl(void);
	#else
	#define nfs_register_sysctl() 0
	#define nfs_unregister_sysctl() do { } while(0)
	#endif

	/*
	* linux/fs/nfs/namespace.c
	*/
	extern struct list_head nfs_automount_list;
	extern const struct inode_operations nfs_mountpoint_inode_operations;
	extern const struct inode_operations nfs_referral_inode_operations;
	extern int nfs_mountpoint_expiry_timeout;
	extern void nfs_release_automount_timer(void);

	/*
	* linux/fs/nfs/unlink.c
	*/
	extern int nfs_async_unlink(struct dentry *);
	extern void nfs_complete_unlink(struct dentry *);

	/*
	* linux/fs/nfs/write.c
	*/
	extern int nfs_writepage(struct page page, struct writeback_control wbc);
	extern int nfs_writepages(struct address_space , struct writeback_control );
	extern int nfs_flush_incompatible(struct file file, struct page page);
	extern int nfs_updatepage(struct file , struct page , unsigned int, unsigned int);
	extern int nfs_writeback_done(struct rpc_task , struct nfs_write_data );
	extern void nfs_writedata_release(void *);
	extern int nfs_set_page_dirty(struct page *);

	/*
	* Try to write back everything synchronously (but check the
	* return value!)
	*/
	extern long nfs_sync_mapping_wait(struct address_space , struct writeback_control , int);
	extern int nfs_sync_mapping_range(struct address_space *, loff_t, loff_t, int);
	extern int nfs_wb_all(struct inode *inode);
	extern int nfs_wb_page(struct inode inode, struct page page);
	extern int nfs_wb_page_priority(struct inode inode, struct page page, int how);
	#if defined(CONFIG_NFS_V3) \|\| defined(CONFIG_NFS_V4)
	extern int nfs_commit_inode(struct inode *, int);
	extern struct nfs_write_data *nfs_commit_alloc(void);
	extern void nfs_commit_free(struct nfs_write_data *wdata);
	extern void nfs_commit_release(void *wdata);
	#else
	static inline int
	nfs_commit_inode(struct inode *inode, int how)
	{
	return 0;
	}
	#endif

	static inline int
	nfs_have_writebacks(struct inode *inode)
	{
	return NFS_I(inode)->npages != 0;
	}

	/*
	* Allocate nfs_write_data structures
	*/
	extern struct nfs_write_data *nfs_writedata_alloc(size_t len);

	/*
	* linux/fs/nfs/read.c
	*/
	extern int nfs_readpage(struct file , struct page );
	extern int nfs_readpages(struct file , struct address_space ,
	struct list_head *, unsigned);
	extern int nfs_readpage_result(struct rpc_task , struct nfs_read_data );
	extern void nfs_readdata_release(void *data);

	/*
	* Allocate nfs_read_data structures
	*/
	extern struct nfs_read_data *nfs_readdata_alloc(size_t len);

	/*
	* linux/fs/nfs3proc.c
	*/
	#ifdef CONFIG_NFS_V3_ACL
	extern struct posix_acl nfs3_proc_getacl(struct inode inode, int type);
	extern int nfs3_proc_setacl(struct inode *inode, int type,
	struct posix_acl *acl);
	extern int nfs3_proc_set_default_acl(struct inode dir, struct inode inode,
	mode_t mode);
	extern void nfs3_forget_cached_acls(struct inode *inode);
	#else
	static inline int nfs3_proc_set_default_acl(struct inode *dir,
	struct inode *inode,
	mode_t mode)
	{
	return 0;
	}

	static inline void nfs3_forget_cached_acls(struct inode *inode)
	{
	}
	#endif /* CONFIG_NFS_V3_ACL */

	/*
	* linux/fs/mount_clnt.c
	* (Used only by nfsroot module)
	*/
	extern int nfsroot_mount(struct sockaddr_in , char , struct nfs_fh *,
	int, int);

	/*
	* inline functions
	*/

	static inline loff_t
	nfs_size_to_loff_t(__u64 size)
	{
	loff_t maxsz = (((loff_t) ULONG_MAX) << PAGE_CACHE_SHIFT) + PAGE_CACHE_SIZE - 1;
	if (size > maxsz)
	return maxsz;
	return (loff_t) size;
	}

	static inline ino_t
	nfs_fileid_to_ino_t(u64 fileid)
	{
	ino_t ino = (ino_t) fileid;
	if (sizeof(ino_t) < sizeof(u64))
	ino ^= fileid >> (sizeof(u64)-sizeof(ino_t)) * 8;
	return ino;
	}

	/* NFS root */

	extern void * nfs_root_data(void);

	#define nfs_wait_event(clnt, wq, condition) \
	({ \
	int __retval = 0; \
	if (clnt->cl_intr) { \
	sigset_t oldmask; \
	rpc_clnt_sigmask(clnt, &oldmask); \
	__retval = wait_event_interruptible(wq, condition); \
	rpc_clnt_sigunmask(clnt, &oldmask); \
	} else \
	wait_event(wq, condition); \
	__retval; \
	})

	#define NFS_JUKEBOX_RETRY_TIME (5 * HZ)

	#endif /* __KERNEL__ */

	/*
	* NFS debug flags
	*/
	#define NFSDBG_VFS 0x0001
	#define NFSDBG_DIRCACHE 0x0002
	#define NFSDBG_LOOKUPCACHE 0x0004
	#define NFSDBG_PAGECACHE 0x0008
	#define NFSDBG_PROC 0x0010
	#define NFSDBG_XDR 0x0020
	#define NFSDBG_FILE 0x0040
	#define NFSDBG_ROOT 0x0080
	#define NFSDBG_CALLBACK 0x0100
	#define NFSDBG_CLIENT 0x0200
	#define NFSDBG_ALL 0xFFFF

	#ifdef __KERNEL__
	# undef ifdebug
	# ifdef NFS_DEBUG
	# define ifdebug(fac) if (unlikely(nfs_debug & NFSDBG_##fac))
	# else
	# define ifdebug(fac) if (0)
	# endif
	#endif /* __KERNEL */

	#endif