fs/nfs/internal.h - kernel/msm-4.9 - Gitiles

 /*
  * NFS internal definitions
  */

 #include "nfs4_fs.h"
 #include <linux/mount.h>
 #include <linux/security.h>

 #define NFS_MS_MASK (MS_RDONLY|MS_NOSUID|MS_NODEV|MS_NOEXEC|MS_SYNCHRONOUS)

 struct nfs_string;

 /* Maximum number of readahead requests
  * FIXME: this should really be a sysctl so that users may tune it to suit
  *        their needs. People that do NFS over a slow network, might for
  *        instance want to reduce it to something closer to 1 for improved
  *        interactive response.
  */
 #define NFS_MAX_READAHEAD	(RPC_DEF_SLOT_TABLE - 1)

 /*
  * Determine if sessions are in use.
  */
 static inline int nfs4_has_session(const struct nfs_client *clp)
 {
 #ifdef CONFIG_NFS_V4_1
 	if (clp->cl_session)
 		return 1;
 #endif /* CONFIG_NFS_V4_1 */
 	return 0;
 }

 static inline int nfs4_has_persistent_session(const struct nfs_client *clp)
 {
 #ifdef CONFIG_NFS_V4_1
 	if (nfs4_has_session(clp))
 		return (clp->cl_session->flags & SESSION4_PERSIST);
 #endif /* CONFIG_NFS_V4_1 */
 	return 0;
 }

 static inline void nfs_attr_check_mountpoint(struct super_block *parent, struct nfs_fattr *fattr)
 {
 	if (!nfs_fsid_equal(&NFS_SB(parent)->fsid, &fattr->fsid))
 		fattr->valid |= NFS_ATTR_FATTR_MOUNTPOINT;
 }

 static inline int nfs_attr_use_mounted_on_fileid(struct nfs_fattr *fattr)
 {
 	if (((fattr->valid & NFS_ATTR_FATTR_MOUNTED_ON_FILEID) == 0) ||
 	    (((fattr->valid & NFS_ATTR_FATTR_MOUNTPOINT) == 0) &&
 	     ((fattr->valid & NFS_ATTR_FATTR_V4_REFERRAL) == 0)))
 		return 0;

 	fattr->fileid = fattr->mounted_on_fileid;
 	return 1;
 }

 struct nfs_clone_mount {
 	const struct super_block *sb;
 	const struct dentry *dentry;
 	struct nfs_fh *fh;
 	struct nfs_fattr *fattr;
 	char *hostname;
 	char *mnt_path;
 	struct sockaddr *addr;
 	size_t addrlen;
 	rpc_authflavor_t authflavor;
 };

 /*
  * Note: RFC 1813 doesn't limit the number of auth flavors that
  * a server can return, so make something up.
  */
 #define NFS_MAX_SECFLAVORS	(12)

 /*
  * Value used if the user did not specify a port value.
  */
 #define NFS_UNSPEC_PORT		(-1)

 /*
  * Maximum number of pages that readdir can use for creating
  * a vmapped array of pages.
  */
 #define NFS_MAX_READDIR_PAGES 8

 /*
  * In-kernel mount arguments
  */
 struct nfs_parsed_mount_data {
 	int			flags;
 	int			rsize, wsize;
 	int			timeo, retrans;
 	int			acregmin, acregmax,
 				acdirmin, acdirmax;
 	int			namlen;
 	unsigned int		options;
 	unsigned int		bsize;
 	unsigned int		auth_flavor_len;
 	rpc_authflavor_t	auth_flavors[1];
 	char			*client_address;
 	unsigned int		version;
 	unsigned int		minorversion;
 	char			*fscache_uniq;

 	struct {
 		struct sockaddr_storage	address;
 		size_t			addrlen;
 		char			*hostname;
 		u32			version;
 		int			port;
 		unsigned short		protocol;
 	} mount_server;

 	struct {
 		struct sockaddr_storage	address;
 		size_t			addrlen;
 		char			*hostname;
 		char			*export_path;
 		int			port;
 		unsigned short		protocol;
 	} nfs_server;

 	struct security_mnt_opts lsm_opts;
 	struct net		*net;
 };

 /* mount_clnt.c */
 struct nfs_mount_request {
 	struct sockaddr		*sap;
 	size_t			salen;
 	char			*hostname;
 	char			*dirpath;
 	u32			version;
 	unsigned short		protocol;
 	struct nfs_fh		*fh;
 	int			noresvport;
 	unsigned int		*auth_flav_len;
 	rpc_authflavor_t	*auth_flavs;
 	struct net		*net;
 };

 extern int nfs_mount(struct nfs_mount_request *info);
 extern void nfs_umount(const struct nfs_mount_request *info);

 /* client.c */
 extern const struct rpc_program nfs_program;

 extern void nfs_cleanup_cb_ident_idr(void);
 extern void nfs_put_client(struct nfs_client *);
 extern struct nfs_client *nfs4_find_client_ident(int);
 extern struct nfs_client *
 nfs4_find_client_sessionid(const struct sockaddr *, struct nfs4_sessionid *);
 extern struct nfs_server *nfs_create_server(
 					const struct nfs_parsed_mount_data *,
 					struct nfs_fh *);
 extern struct nfs_server *nfs4_create_server(
 					const struct nfs_parsed_mount_data *,
 					struct nfs_fh *);
 extern struct nfs_server *nfs4_create_referral_server(struct nfs_clone_mount *,
 						      struct nfs_fh *);
 extern void nfs_free_server(struct nfs_server *server);
 extern struct nfs_server *nfs_clone_server(struct nfs_server *,
 					   struct nfs_fh *,
 					   struct nfs_fattr *);
 extern void nfs_mark_client_ready(struct nfs_client *clp, int state);
 extern int nfs4_check_client_ready(struct nfs_client *clp);
 extern struct nfs_client *nfs4_set_ds_client(struct nfs_client* mds_clp,
 					     const struct sockaddr *ds_addr,
 					     int ds_addrlen, int ds_proto);
 #ifdef CONFIG_PROC_FS
 extern int __init nfs_fs_proc_init(void);
 extern void nfs_fs_proc_exit(void);
 #else
 static inline int nfs_fs_proc_init(void)
 {
 	return 0;
 }
 static inline void nfs_fs_proc_exit(void)
 {
 }
 #endif
 #ifdef CONFIG_NFS_V4
 extern spinlock_t nfs_client_lock;
 extern struct list_head nfs_client_list;
 #endif

 /* nfs4namespace.c */
 #ifdef CONFIG_NFS_V4
 extern struct vfsmount *nfs_do_refmount(struct dentry *dentry);
 #else
 static inline
 struct vfsmount *nfs_do_refmount(struct dentry *dentry)
 {
 	return ERR_PTR(-ENOENT);
 }
 #endif

 /* callback_xdr.c */
 extern struct svc_version nfs4_callback_version1;
 extern struct svc_version nfs4_callback_version4;

 /* pagelist.c */
 extern int __init nfs_init_nfspagecache(void);
 extern void nfs_destroy_nfspagecache(void);
 extern int __init nfs_init_readpagecache(void);
 extern void nfs_destroy_readpagecache(void);
 extern int __init nfs_init_writepagecache(void);
 extern void nfs_destroy_writepagecache(void);

 extern int __init nfs_init_directcache(void);
 extern void nfs_destroy_directcache(void);

 /* nfs2xdr.c */
 extern int nfs_stat_to_errno(enum nfs_stat);
 extern struct rpc_procinfo nfs_procedures[];
 extern int nfs2_decode_dirent(struct xdr_stream *,
 				struct nfs_entry *, int);

 /* nfs3xdr.c */
 extern struct rpc_procinfo nfs3_procedures[];
 extern int nfs3_decode_dirent(struct xdr_stream *,
 				struct nfs_entry *, int);

 /* nfs4xdr.c */
 #ifdef CONFIG_NFS_V4
 extern int nfs4_decode_dirent(struct xdr_stream *,
 				struct nfs_entry *, int);
 #endif
 #ifdef CONFIG_NFS_V4_1
 extern const u32 nfs41_maxread_overhead;
 extern const u32 nfs41_maxwrite_overhead;
 #endif

 /* nfs4proc.c */
 #ifdef CONFIG_NFS_V4
 extern struct rpc_procinfo nfs4_procedures[];
 void nfs_fixup_secinfo_attributes(struct nfs_fattr *, struct nfs_fh *);
 #endif

 extern int nfs4_init_ds_session(struct nfs_client *clp);

 /* proc.c */
 void nfs_close_context(struct nfs_open_context *ctx, int is_sync);
 extern int nfs_init_client(struct nfs_client *clp,
 			   const struct rpc_timeout *timeparms,
 			   const char *ip_addr, rpc_authflavor_t authflavour,
 			   int noresvport);

 /* dir.c */
 extern int nfs_access_cache_shrinker(struct shrinker *shrink,
 					struct shrink_control *sc);

 /* inode.c */
 extern struct workqueue_struct *nfsiod_workqueue;
 extern struct inode *nfs_alloc_inode(struct super_block *sb);
 extern void nfs_destroy_inode(struct inode *);
 extern int nfs_write_inode(struct inode *, struct writeback_control *);
 extern void nfs_evict_inode(struct inode *);
 #ifdef CONFIG_NFS_V4
 extern void nfs4_evict_inode(struct inode *);
 #endif
 void nfs_zap_acl_cache(struct inode *inode);
 extern int nfs_wait_bit_killable(void *word);

 /* super.c */
 extern struct file_system_type nfs_xdev_fs_type;
 #ifdef CONFIG_NFS_V4
 extern struct file_system_type nfs4_xdev_fs_type;
 extern struct file_system_type nfs4_referral_fs_type;
 #endif

 extern struct rpc_stat nfs_rpcstat;

 extern int __init register_nfs_fs(void);
 extern void __exit unregister_nfs_fs(void);
 extern void nfs_sb_active(struct super_block *sb);
 extern void nfs_sb_deactive(struct super_block *sb);

 /* namespace.c */
 extern char *nfs_path(char **p, struct dentry *dentry,
 		      char *buffer, ssize_t buflen);
 extern struct vfsmount *nfs_d_automount(struct path *path);
 #ifdef CONFIG_NFS_V4
 rpc_authflavor_t nfs_find_best_sec(struct nfs4_secinfo_flavors *);
 #endif

 /* getroot.c */
 extern struct dentry *nfs_get_root(struct super_block *, struct nfs_fh *,
 				   const char *);
 #ifdef CONFIG_NFS_V4
 extern struct dentry *nfs4_get_root(struct super_block *, struct nfs_fh *,
 				    const char *);

 extern int nfs4_get_rootfh(struct nfs_server *server, struct nfs_fh *mntfh);
 #endif

 struct nfs_pageio_descriptor;
 /* read.c */
 extern int nfs_initiate_read(struct nfs_read_data *data, struct rpc_clnt *clnt,
 			     const struct rpc_call_ops *call_ops);
 extern void nfs_read_prepare(struct rpc_task *task, void *calldata);
 extern int nfs_generic_pagein(struct nfs_pageio_descriptor *desc,
 		struct list_head *head);

 extern void nfs_pageio_init_read_mds(struct nfs_pageio_descriptor *pgio,
 		struct inode *inode);
 extern void nfs_pageio_reset_read_mds(struct nfs_pageio_descriptor *pgio);
 extern void nfs_readdata_release(struct nfs_read_data *rdata);

 /* write.c */
 extern int nfs_generic_flush(struct nfs_pageio_descriptor *desc,
 		struct list_head *head);
 extern void nfs_pageio_init_write_mds(struct nfs_pageio_descriptor *pgio,
 				  struct inode *inode, int ioflags);
 extern void nfs_pageio_reset_write_mds(struct nfs_pageio_descriptor *pgio);
 extern void nfs_writedata_release(struct nfs_write_data *wdata);
 extern void nfs_commit_free(struct nfs_write_data *p);
 extern int nfs_initiate_write(struct nfs_write_data *data,
 			      struct rpc_clnt *clnt,
 			      const struct rpc_call_ops *call_ops,
 			      int how);
 extern void nfs_write_prepare(struct rpc_task *task, void *calldata);
 extern int nfs_initiate_commit(struct nfs_write_data *data,
 			       struct rpc_clnt *clnt,
 			       const struct rpc_call_ops *call_ops,
 			       int how);
 extern void nfs_init_commit(struct nfs_write_data *data,
 			    struct list_head *head,
 			    struct pnfs_layout_segment *lseg);
 void nfs_retry_commit(struct list_head *page_list,
 		      struct pnfs_layout_segment *lseg);
 void nfs_commit_clear_lock(struct nfs_inode *nfsi);
 void nfs_commitdata_release(void *data);
 void nfs_commit_release_pages(struct nfs_write_data *data);

 #ifdef CONFIG_MIGRATION
 extern int nfs_migrate_page(struct address_space *,
 		struct page *, struct page *, enum migrate_mode);
 #else
 #define nfs_migrate_page NULL
 #endif

 /* nfs4proc.c */
 extern void __nfs4_read_done_cb(struct nfs_read_data *);
 extern void nfs4_reset_read(struct rpc_task *task, struct nfs_read_data *data);
 extern int nfs4_init_client(struct nfs_client *clp,
 			    const struct rpc_timeout *timeparms,
 			    const char *ip_addr,
 			    rpc_authflavor_t authflavour,
 			    int noresvport);
 extern void nfs4_reset_write(struct rpc_task *task, struct nfs_write_data *data);
 extern int _nfs4_call_sync(struct rpc_clnt *clnt,
 			   struct nfs_server *server,
 			   struct rpc_message *msg,
 			   struct nfs4_sequence_args *args,
 			   struct nfs4_sequence_res *res,
 			   int cache_reply);
 extern int _nfs4_call_sync_session(struct rpc_clnt *clnt,
 				   struct nfs_server *server,
 				   struct rpc_message *msg,
 				   struct nfs4_sequence_args *args,
 				   struct nfs4_sequence_res *res,
 				   int cache_reply);

 /*
  * Determine the device name as a string
  */
 static inline char *nfs_devname(struct dentry *dentry,
 				char *buffer, ssize_t buflen)
 {
 	char *dummy;
 	return nfs_path(&dummy, dentry, buffer, buflen);
 }

 /*
  * Determine the actual block size (and log2 thereof)
  */
 static inline
 unsigned long nfs_block_bits(unsigned long bsize, unsigned char *nrbitsp)
 {
 	/* make sure blocksize is a power of two */
 	if ((bsize & (bsize - 1)) || nrbitsp) {
 		unsigned char	nrbits;

 		for (nrbits = 31; nrbits && !(bsize & (1 << nrbits)); nrbits--)
 			;
 		bsize = 1 << nrbits;
 		if (nrbitsp)
 			*nrbitsp = nrbits;
 	}

 	return bsize;
 }

 /*
  * Calculate the number of 512byte blocks used.
  */
 static inline blkcnt_t nfs_calc_block_size(u64 tsize)
 {
 	blkcnt_t used = (tsize + 511) >> 9;
 	return (used > ULONG_MAX) ? ULONG_MAX : used;
 }

 /*
  * Compute and set NFS server blocksize
  */
 static inline
 unsigned long nfs_block_size(unsigned long bsize, unsigned char *nrbitsp)
 {
 	if (bsize < NFS_MIN_FILE_IO_SIZE)
 		bsize = NFS_DEF_FILE_IO_SIZE;
 	else if (bsize >= NFS_MAX_FILE_IO_SIZE)
 		bsize = NFS_MAX_FILE_IO_SIZE;

 	return nfs_block_bits(bsize, nrbitsp);
 }

 /*
  * Determine the maximum file size for a superblock
  */
 static inline
 void nfs_super_set_maxbytes(struct super_block *sb, __u64 maxfilesize)
 {
 	sb->s_maxbytes = (loff_t)maxfilesize;
 	if (sb->s_maxbytes > MAX_LFS_FILESIZE || sb->s_maxbytes <= 0)
 		sb->s_maxbytes = MAX_LFS_FILESIZE;
 }

 /*
  * Determine the number of bytes of data the page contains
  */
 static inline
 unsigned int nfs_page_length(struct page *page)
 {
 	loff_t i_size = i_size_read(page->mapping->host);

 	if (i_size > 0) {
 		pgoff_t end_index = (i_size - 1) >> PAGE_CACHE_SHIFT;
 		if (page->index < end_index)
 			return PAGE_CACHE_SIZE;
 		if (page->index == end_index)
 			return ((i_size - 1) & ~PAGE_CACHE_MASK) + 1;
 	}
 	return 0;
 }

 /*
  * Convert a umode to a dirent->d_type
  */
 static inline
 unsigned char nfs_umode_to_dtype(umode_t mode)
 {
 	return (mode >> 12) & 15;
 }

 /*
  * Determine the number of pages in an array of length 'len' and
  * with a base offset of 'base'
  */
 static inline
 unsigned int nfs_page_array_len(unsigned int base, size_t len)
 {
 	return ((unsigned long)len + (unsigned long)base +
 		PAGE_SIZE - 1) >> PAGE_SHIFT;
 }
	/*
	* NFS internal definitions
	*/

	#include "nfs4_fs.h"
	#include <linux/mount.h>
	#include <linux/security.h>

	#define NFS_MS_MASK (MS_RDONLY\|MS_NOSUID\|MS_NODEV\|MS_NOEXEC\|MS_SYNCHRONOUS)

	struct nfs_string;

	/* Maximum number of readahead requests
	* FIXME: this should really be a sysctl so that users may tune it to suit
	* their needs. People that do NFS over a slow network, might for
	* instance want to reduce it to something closer to 1 for improved
	* interactive response.
	*/
	#define NFS_MAX_READAHEAD (RPC_DEF_SLOT_TABLE - 1)

	/*
	* Determine if sessions are in use.
	*/
	static inline int nfs4_has_session(const struct nfs_client *clp)
	{
	#ifdef CONFIG_NFS_V4_1
	if (clp->cl_session)
	return 1;
	#endif /* CONFIG_NFS_V4_1 */
	return 0;
	}

	static inline int nfs4_has_persistent_session(const struct nfs_client *clp)
	{
	#ifdef CONFIG_NFS_V4_1
	if (nfs4_has_session(clp))
	return (clp->cl_session->flags & SESSION4_PERSIST);
	#endif /* CONFIG_NFS_V4_1 */
	return 0;
	}

	static inline void nfs_attr_check_mountpoint(struct super_block parent, struct nfs_fattr fattr)
	{
	if (!nfs_fsid_equal(&NFS_SB(parent)->fsid, &fattr->fsid))
	fattr->valid \|= NFS_ATTR_FATTR_MOUNTPOINT;
	}

	static inline int nfs_attr_use_mounted_on_fileid(struct nfs_fattr *fattr)
	{
	if (((fattr->valid & NFS_ATTR_FATTR_MOUNTED_ON_FILEID) == 0) \|\|
	(((fattr->valid & NFS_ATTR_FATTR_MOUNTPOINT) == 0) &&
	((fattr->valid & NFS_ATTR_FATTR_V4_REFERRAL) == 0)))
	return 0;

	fattr->fileid = fattr->mounted_on_fileid;
	return 1;
	}

	struct nfs_clone_mount {
	const struct super_block *sb;
	const struct dentry *dentry;
	struct nfs_fh *fh;
	struct nfs_fattr *fattr;
	char *hostname;
	char *mnt_path;
	struct sockaddr *addr;
	size_t addrlen;
	rpc_authflavor_t authflavor;
	};

	/*
	* Note: RFC 1813 doesn't limit the number of auth flavors that
	* a server can return, so make something up.
	*/
	#define NFS_MAX_SECFLAVORS (12)

	/*
	* Value used if the user did not specify a port value.
	*/
	#define NFS_UNSPEC_PORT (-1)

	/*
	* Maximum number of pages that readdir can use for creating
	* a vmapped array of pages.
	*/
	#define NFS_MAX_READDIR_PAGES 8

	/*
	* In-kernel mount arguments
	*/
	struct nfs_parsed_mount_data {
	int flags;
	int rsize, wsize;
	int timeo, retrans;
	int acregmin, acregmax,
	acdirmin, acdirmax;
	int namlen;
	unsigned int options;
	unsigned int bsize;
	unsigned int auth_flavor_len;
	rpc_authflavor_t auth_flavors[1];
	char *client_address;
	unsigned int version;
	unsigned int minorversion;
	char *fscache_uniq;

	struct {
	struct sockaddr_storage address;
	size_t addrlen;
	char *hostname;
	u32 version;
	int port;
	unsigned short protocol;
	} mount_server;

	struct {
	struct sockaddr_storage address;
	size_t addrlen;
	char *hostname;
	char *export_path;
	int port;
	unsigned short protocol;
	} nfs_server;

	struct security_mnt_opts lsm_opts;
	struct net *net;
	};

	/* mount_clnt.c */
	struct nfs_mount_request {
	struct sockaddr *sap;
	size_t salen;
	char *hostname;
	char *dirpath;
	u32 version;
	unsigned short protocol;
	struct nfs_fh *fh;
	int noresvport;
	unsigned int *auth_flav_len;
	rpc_authflavor_t *auth_flavs;
	struct net *net;
	};

	extern int nfs_mount(struct nfs_mount_request *info);
	extern void nfs_umount(const struct nfs_mount_request *info);

	/* client.c */
	extern const struct rpc_program nfs_program;

	extern void nfs_cleanup_cb_ident_idr(void);
	extern void nfs_put_client(struct nfs_client *);
	extern struct nfs_client *nfs4_find_client_ident(int);
	extern struct nfs_client *
	nfs4_find_client_sessionid(const struct sockaddr , struct nfs4_sessionid );
	extern struct nfs_server *nfs_create_server(
	const struct nfs_parsed_mount_data *,
	struct nfs_fh *);
	extern struct nfs_server *nfs4_create_server(
	const struct nfs_parsed_mount_data *,
	struct nfs_fh *);
	extern struct nfs_server nfs4_create_referral_server(struct nfs_clone_mount ,
	struct nfs_fh *);
	extern void nfs_free_server(struct nfs_server *server);
	extern struct nfs_server nfs_clone_server(struct nfs_server ,
	struct nfs_fh *,
	struct nfs_fattr *);
	extern void nfs_mark_client_ready(struct nfs_client *clp, int state);
	extern int nfs4_check_client_ready(struct nfs_client *clp);
	extern struct nfs_client nfs4_set_ds_client(struct nfs_client mds_clp,
	const struct sockaddr *ds_addr,
	int ds_addrlen, int ds_proto);
	#ifdef CONFIG_PROC_FS
	extern int __init nfs_fs_proc_init(void);
	extern void nfs_fs_proc_exit(void);
	#else
	static inline int nfs_fs_proc_init(void)
	{
	return 0;
	}
	static inline void nfs_fs_proc_exit(void)
	{
	}
	#endif
	#ifdef CONFIG_NFS_V4
	extern spinlock_t nfs_client_lock;
	extern struct list_head nfs_client_list;
	#endif

	/* nfs4namespace.c */
	#ifdef CONFIG_NFS_V4
	extern struct vfsmount nfs_do_refmount(struct dentry dentry);
	#else
	static inline
	struct vfsmount nfs_do_refmount(struct dentry dentry)
	{
	return ERR_PTR(-ENOENT);
	}
	#endif

	/* callback_xdr.c */
	extern struct svc_version nfs4_callback_version1;
	extern struct svc_version nfs4_callback_version4;

	/* pagelist.c */
	extern int __init nfs_init_nfspagecache(void);
	extern void nfs_destroy_nfspagecache(void);
	extern int __init nfs_init_readpagecache(void);
	extern void nfs_destroy_readpagecache(void);
	extern int __init nfs_init_writepagecache(void);
	extern void nfs_destroy_writepagecache(void);

	extern int __init nfs_init_directcache(void);
	extern void nfs_destroy_directcache(void);

	/* nfs2xdr.c */
	extern int nfs_stat_to_errno(enum nfs_stat);
	extern struct rpc_procinfo nfs_procedures[];
	extern int nfs2_decode_dirent(struct xdr_stream *,
	struct nfs_entry *, int);

	/* nfs3xdr.c */
	extern struct rpc_procinfo nfs3_procedures[];
	extern int nfs3_decode_dirent(struct xdr_stream *,
	struct nfs_entry *, int);

	/* nfs4xdr.c */
	#ifdef CONFIG_NFS_V4
	extern int nfs4_decode_dirent(struct xdr_stream *,
	struct nfs_entry *, int);
	#endif
	#ifdef CONFIG_NFS_V4_1
	extern const u32 nfs41_maxread_overhead;
	extern const u32 nfs41_maxwrite_overhead;
	#endif

	/* nfs4proc.c */
	#ifdef CONFIG_NFS_V4
	extern struct rpc_procinfo nfs4_procedures[];
	void nfs_fixup_secinfo_attributes(struct nfs_fattr , struct nfs_fh );
	#endif

	extern int nfs4_init_ds_session(struct nfs_client *clp);

	/* proc.c */
	void nfs_close_context(struct nfs_open_context *ctx, int is_sync);
	extern int nfs_init_client(struct nfs_client *clp,
	const struct rpc_timeout *timeparms,
	const char *ip_addr, rpc_authflavor_t authflavour,
	int noresvport);

	/* dir.c */
	extern int nfs_access_cache_shrinker(struct shrinker *shrink,
	struct shrink_control *sc);

	/* inode.c */
	extern struct workqueue_struct *nfsiod_workqueue;
	extern struct inode nfs_alloc_inode(struct super_block sb);
	extern void nfs_destroy_inode(struct inode *);
	extern int nfs_write_inode(struct inode , struct writeback_control );
	extern void nfs_evict_inode(struct inode *);
	#ifdef CONFIG_NFS_V4
	extern void nfs4_evict_inode(struct inode *);
	#endif
	void nfs_zap_acl_cache(struct inode *inode);
	extern int nfs_wait_bit_killable(void *word);

	/* super.c */
	extern struct file_system_type nfs_xdev_fs_type;
	#ifdef CONFIG_NFS_V4
	extern struct file_system_type nfs4_xdev_fs_type;
	extern struct file_system_type nfs4_referral_fs_type;
	#endif

	extern struct rpc_stat nfs_rpcstat;

	extern int __init register_nfs_fs(void);
	extern void __exit unregister_nfs_fs(void);
	extern void nfs_sb_active(struct super_block *sb);
	extern void nfs_sb_deactive(struct super_block *sb);

	/* namespace.c */
	extern char nfs_path(char p, struct dentry dentry,
	char *buffer, ssize_t buflen);
	extern struct vfsmount nfs_d_automount(struct path path);
	#ifdef CONFIG_NFS_V4
	rpc_authflavor_t nfs_find_best_sec(struct nfs4_secinfo_flavors *);
	#endif

	/* getroot.c */
	extern struct dentry nfs_get_root(struct super_block , struct nfs_fh *,
	const char *);
	#ifdef CONFIG_NFS_V4
	extern struct dentry nfs4_get_root(struct super_block , struct nfs_fh *,
	const char *);

	extern int nfs4_get_rootfh(struct nfs_server server, struct nfs_fh mntfh);
	#endif

	struct nfs_pageio_descriptor;
	/* read.c */
	extern int nfs_initiate_read(struct nfs_read_data data, struct rpc_clnt clnt,
	const struct rpc_call_ops *call_ops);
	extern void nfs_read_prepare(struct rpc_task task, void calldata);
	extern int nfs_generic_pagein(struct nfs_pageio_descriptor *desc,
	struct list_head *head);

	extern void nfs_pageio_init_read_mds(struct nfs_pageio_descriptor *pgio,
	struct inode *inode);
	extern void nfs_pageio_reset_read_mds(struct nfs_pageio_descriptor *pgio);
	extern void nfs_readdata_release(struct nfs_read_data *rdata);

	/* write.c */
	extern int nfs_generic_flush(struct nfs_pageio_descriptor *desc,
	struct list_head *head);
	extern void nfs_pageio_init_write_mds(struct nfs_pageio_descriptor *pgio,
	struct inode *inode, int ioflags);
	extern void nfs_pageio_reset_write_mds(struct nfs_pageio_descriptor *pgio);
	extern void nfs_writedata_release(struct nfs_write_data *wdata);
	extern void nfs_commit_free(struct nfs_write_data *p);
	extern int nfs_initiate_write(struct nfs_write_data *data,
	struct rpc_clnt *clnt,
	const struct rpc_call_ops *call_ops,
	int how);
	extern void nfs_write_prepare(struct rpc_task task, void calldata);
	extern int nfs_initiate_commit(struct nfs_write_data *data,
	struct rpc_clnt *clnt,
	const struct rpc_call_ops *call_ops,
	int how);
	extern void nfs_init_commit(struct nfs_write_data *data,
	struct list_head *head,
	struct pnfs_layout_segment *lseg);
	void nfs_retry_commit(struct list_head *page_list,
	struct pnfs_layout_segment *lseg);
	void nfs_commit_clear_lock(struct nfs_inode *nfsi);
	void nfs_commitdata_release(void *data);
	void nfs_commit_release_pages(struct nfs_write_data *data);

	#ifdef CONFIG_MIGRATION
	extern int nfs_migrate_page(struct address_space *,
	struct page , struct page , enum migrate_mode);
	#else
	#define nfs_migrate_page NULL
	#endif

	/* nfs4proc.c */
	extern void __nfs4_read_done_cb(struct nfs_read_data *);
	extern void nfs4_reset_read(struct rpc_task task, struct nfs_read_data data);
	extern int nfs4_init_client(struct nfs_client *clp,
	const struct rpc_timeout *timeparms,
	const char *ip_addr,
	rpc_authflavor_t authflavour,
	int noresvport);
	extern void nfs4_reset_write(struct rpc_task task, struct nfs_write_data data);
	extern int _nfs4_call_sync(struct rpc_clnt *clnt,
	struct nfs_server *server,
	struct rpc_message *msg,
	struct nfs4_sequence_args *args,
	struct nfs4_sequence_res *res,
	int cache_reply);
	extern int _nfs4_call_sync_session(struct rpc_clnt *clnt,
	struct nfs_server *server,
	struct rpc_message *msg,
	struct nfs4_sequence_args *args,
	struct nfs4_sequence_res *res,
	int cache_reply);

	/*
	* Determine the device name as a string
	*/
	static inline char nfs_devname(struct dentry dentry,
	char *buffer, ssize_t buflen)
	{
	char *dummy;
	return nfs_path(&dummy, dentry, buffer, buflen);
	}

	/*
	* Determine the actual block size (and log2 thereof)
	*/
	static inline
	unsigned long nfs_block_bits(unsigned long bsize, unsigned char *nrbitsp)
	{
	/* make sure blocksize is a power of two */
	if ((bsize & (bsize - 1)) \|\| nrbitsp) {
	unsigned char nrbits;

	for (nrbits = 31; nrbits && !(bsize & (1 << nrbits)); nrbits--)
	;
	bsize = 1 << nrbits;
	if (nrbitsp)
	*nrbitsp = nrbits;
	}

	return bsize;
	}

	/*
	* Calculate the number of 512byte blocks used.
	*/
	static inline blkcnt_t nfs_calc_block_size(u64 tsize)
	{
	blkcnt_t used = (tsize + 511) >> 9;
	return (used > ULONG_MAX) ? ULONG_MAX : used;
	}

	/*
	* Compute and set NFS server blocksize
	*/
	static inline
	unsigned long nfs_block_size(unsigned long bsize, unsigned char *nrbitsp)
	{
	if (bsize < NFS_MIN_FILE_IO_SIZE)
	bsize = NFS_DEF_FILE_IO_SIZE;
	else if (bsize >= NFS_MAX_FILE_IO_SIZE)
	bsize = NFS_MAX_FILE_IO_SIZE;

	return nfs_block_bits(bsize, nrbitsp);
	}

	/*
	* Determine the maximum file size for a superblock
	*/
	static inline
	void nfs_super_set_maxbytes(struct super_block *sb, __u64 maxfilesize)
	{
	sb->s_maxbytes = (loff_t)maxfilesize;
	if (sb->s_maxbytes > MAX_LFS_FILESIZE \|\| sb->s_maxbytes <= 0)
	sb->s_maxbytes = MAX_LFS_FILESIZE;
	}

	/*
	* Determine the number of bytes of data the page contains
	*/
	static inline
	unsigned int nfs_page_length(struct page *page)
	{
	loff_t i_size = i_size_read(page->mapping->host);

	if (i_size > 0) {
	pgoff_t end_index = (i_size - 1) >> PAGE_CACHE_SHIFT;
	if (page->index < end_index)
	return PAGE_CACHE_SIZE;
	if (page->index == end_index)
	return ((i_size - 1) & ~PAGE_CACHE_MASK) + 1;
	}
	return 0;
	}

	/*
	* Convert a umode to a dirent->d_type
	*/
	static inline
	unsigned char nfs_umode_to_dtype(umode_t mode)
	{
	return (mode >> 12) & 15;
	}

	/*
	* Determine the number of pages in an array of length 'len' and
	* with a base offset of 'base'
	*/
	static inline
	unsigned int nfs_page_array_len(unsigned int base, size_t len)
	{
	return ((unsigned long)len + (unsigned long)base +
	PAGE_SIZE - 1) >> PAGE_SHIFT;
	}