[mirror_ubuntu-bionic-kernel.git] / fs / nfs / internal.h

/*
 * 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;
}

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)

/*
 * 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;
};

/* 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;
};

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

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

extern void nfs_put_client(struct nfs_client *);
extern struct nfs_client *nfs_find_client(const struct sockaddr *, u32);
extern struct nfs_client *nfs_find_client_next(struct nfs_client *);
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);
#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

/* nfs4namespace.c */
#ifdef CONFIG_NFS_V4
extern struct vfsmount *nfs_do_refmount(const struct vfsmount *mnt_parent, struct dentry *dentry);
#else
static inline
struct vfsmount *nfs_do_refmount(const struct vfsmount *mnt_parent, 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(int);
extern struct rpc_procinfo nfs_procedures[];
extern __be32 * nfs_decode_dirent(__be32 *, struct nfs_entry *, int);

/* nfs3xdr.c */
extern struct rpc_procinfo nfs3_procedures[];
extern __be32 *nfs3_decode_dirent(__be32 *, struct nfs_entry *, int);

/* nfs4xdr.c */
#ifdef CONFIG_NFS_V4
extern __be32 *nfs4_decode_dirent(__be32 *p, struct nfs_entry *entry, int plus);
#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[];
#endif

/* proc.c */
void nfs_close_context(struct nfs_open_context *ctx, int is_sync);

/* dir.c */
extern int nfs_access_cache_shrinker(int nr_to_scan, gfp_t gfp_mask);

/* 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_clear_inode(struct inode *);
#ifdef CONFIG_NFS_V4
extern void nfs4_clear_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(const char *base,
		      const struct dentry *droot,
		      const struct dentry *dentry,
		      char *buffer, ssize_t buflen);

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

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

/* read.c */
extern void nfs_read_prepare(struct rpc_task *task, void *calldata);

/* write.c */
extern void nfs_write_prepare(struct rpc_task *task, void *calldata);
#ifdef CONFIG_MIGRATION
extern int nfs_migrate_page(struct address_space *,
		struct page *, struct page *);
#else
#define nfs_migrate_page NULL
#endif

/* nfs4proc.c */
extern int _nfs4_call_sync(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 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(const struct vfsmount *mnt_parent,
				const struct dentry *dentry,
				char *buffer, ssize_t buflen)
{
	return nfs_path(mnt_parent->mnt_devname, mnt_parent->mnt_root,
			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;
}

/*
 * 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;
}

/*
 * Helper for restarting RPC calls in the possible presence of NFSv4.1
 * sessions.
 */
static inline void nfs_restart_rpc(struct rpc_task *task, const struct nfs_client *clp)
{
	if (nfs4_has_session(clp))
		rpc_restart_call_prepare(task);
	else
		rpc_restart_call(task);
}
Commit	Line	Data
f7b422b1 DH	1	/*
	2	* NFS internal definitions
	3	*/
	4
eedc020e	5	#include "nfs4_fs.h"
f7b422b1	6	#include <linux/mount.h>
f9c3a380	7	#include <linux/security.h>
f7b422b1	8
08734048 DH	9	#define NFS_MS_MASK (MS_RDONLY\|MS_NOSUID\|MS_NODEV\|MS_NOEXEC\|MS_SYNCHRONOUS)
08734048 DH	10
54ceac45	11	struct nfs_string;
54ceac45 DH	12
	13	/* Maximum number of readahead requests
	14	* FIXME: this should really be a sysctl so that users may tune it to suit
	15	* their needs. People that do NFS over a slow network, might for
	16	* instance want to reduce it to something closer to 1 for improved
	17	* interactive response.
	18	*/
	19	#define NFS_MAX_READAHEAD (RPC_DEF_SLOT_TABLE - 1)
	20
eedc020e AA	21	/*
	22	* Determine if sessions are in use.
	23	*/
	24	static inline int nfs4_has_session(const struct nfs_client *clp)
	25	{
	26	#ifdef CONFIG_NFS_V4_1
	27	if (clp->cl_session)
	28	return 1;
	29	#endif /* CONFIG_NFS_V4_1 */
	30	return 0;
	31	}
	32
d8cb1a7c AB	33	static inline int nfs4_has_persistent_session(const struct nfs_client *clp)
	34	{
	35	#ifdef CONFIG_NFS_V4_1
	36	if (nfs4_has_session(clp))
	37	return (clp->cl_session->flags & SESSION4_PERSIST);
	38	#endif /* CONFIG_NFS_V4_1 */
	39	return 0;
	40	}
	41
f7b422b1 DH	42	struct nfs_clone_mount {
	43	const struct super_block *sb;
	44	const struct dentry *dentry;
	45	struct nfs_fh *fh;
	46	struct nfs_fattr *fattr;
	47	char *hostname;
	48	char *mnt_path;
6677d095 CL	49	struct sockaddr *addr;
6677d095 CL	50	size_t addrlen;
f7b422b1 DH	51	rpc_authflavor_t authflavor;
	52	};
	53
a14017db CL	54	/*
	55	* Note: RFC 1813 doesn't limit the number of auth flavors that
	56	* a server can return, so make something up.
	57	*/
	58	#define NFS_MAX_SECFLAVORS (12)
	59
4cfd74fc CL	60	/*
	61	* Value used if the user did not specify a port value.
	62	*/
	63	#define NFS_UNSPEC_PORT (-1)
	64
6b18eaa0 TT	65	/*
	66	* In-kernel mount arguments
	67	*/
	68	struct nfs_parsed_mount_data {
	69	int flags;
	70	int rsize, wsize;
	71	int timeo, retrans;
	72	int acregmin, acregmax,
	73	acdirmin, acdirmax;
	74	int namlen;
b797cac7	75	unsigned int options;
6b18eaa0 TT	76	unsigned int bsize;
	77	unsigned int auth_flavor_len;
	78	rpc_authflavor_t auth_flavors[1];
	79	char *client_address;
764302cc	80	unsigned int version;
3fd5be9e	81	unsigned int minorversion;
08734048	82	char *fscache_uniq;
6b18eaa0 TT	83
6b18eaa0 TT	84	struct {
4c568017 CL	85	struct sockaddr_storage address;
4c568017 CL	86	size_t addrlen;
6b18eaa0	87	char *hostname;
78fa701f	88	u32 version;
4cfd74fc	89	int port;
78fa701f	90	unsigned short protocol;
6b18eaa0 TT	91	} mount_server;
	92
	93	struct {
4c568017 CL	94	struct sockaddr_storage address;
4c568017 CL	95	size_t addrlen;
6b18eaa0 TT	96	char *hostname;
6b18eaa0 TT	97	char *export_path;
4cfd74fc	98	int port;
78fa701f	99	unsigned short protocol;
6b18eaa0	100	} nfs_server;
f9c3a380 EP	101
f9c3a380 EP	102	struct security_mnt_opts lsm_opts;
6b18eaa0 TT	103	};
6b18eaa0 TT	104
146ec944	105	/* mount_clnt.c */
c5d120f8 CL	106	struct nfs_mount_request {
	107	struct sockaddr *sap;
	108	size_t salen;
	109	char *hostname;
	110	char *dirpath;
	111	u32 version;
	112	unsigned short protocol;
	113	struct nfs_fh *fh;
50a737f8	114	int noresvport;
8e02f6b9 CL	115	unsigned int *auth_flav_len;
8e02f6b9 CL	116	rpc_authflavor_t *auth_flavs;
c5d120f8 CL	117	};
	118
	119	extern int nfs_mount(struct nfs_mount_request *info);
0b524123	120	extern void nfs_umount(const struct nfs_mount_request *info);
146ec944	121
24c8dbbb	122	/* client.c */
54ceac45 DH	123	extern struct rpc_program nfs_program;
54ceac45 DH	124
24c8dbbb	125	extern void nfs_put_client(struct nfs_client *);
ff052645	126	extern struct nfs_client nfs_find_client(const struct sockaddr , u32);
3fbd67ad	127	extern struct nfs_client nfs_find_client_next(struct nfs_client );
2283f8d6 TT	128	extern struct nfs_server *nfs_create_server(
	129	const struct nfs_parsed_mount_data *,
	130	struct nfs_fh *);
91ea40b9 TT	131	extern struct nfs_server *nfs4_create_server(
	132	const struct nfs_parsed_mount_data *,
	133	struct nfs_fh *);
54ceac45 DH	134	extern struct nfs_server nfs4_create_referral_server(struct nfs_clone_mount ,
	135	struct nfs_fh *);
	136	extern void nfs_free_server(struct nfs_server *server);
	137	extern struct nfs_server nfs_clone_server(struct nfs_server ,
	138	struct nfs_fh *,
	139	struct nfs_fattr *);
76db6d95	140	extern void nfs_mark_client_ready(struct nfs_client *clp, int state);
008f55d0	141	extern int nfs4_check_client_ready(struct nfs_client *clp);
6aaca566 DH	142	#ifdef CONFIG_PROC_FS
	143	extern int __init nfs_fs_proc_init(void);
	144	extern void nfs_fs_proc_exit(void);
	145	#else
	146	static inline int nfs_fs_proc_init(void)
	147	{
	148	return 0;
	149	}
	150	static inline void nfs_fs_proc_exit(void)
	151	{
	152	}
	153	#endif
24c8dbbb	154
7d4e2747	155	/* nfs4namespace.c */
f7b422b1 DH	156	#ifdef CONFIG_NFS_V4
	157	extern struct vfsmount nfs_do_refmount(const struct vfsmount mnt_parent, struct dentry *dentry);
	158	#else
	159	static inline
	160	struct vfsmount nfs_do_refmount(const struct vfsmount mnt_parent, struct dentry *dentry)
	161	{
	162	return ERR_PTR(-ENOENT);
	163	}
	164	#endif
	165
	166	/* callback_xdr.c */
	167	extern struct svc_version nfs4_callback_version1;
07bccc2d	168	extern struct svc_version nfs4_callback_version4;
f7b422b1 DH	169
	170	/* pagelist.c */
	171	extern int __init nfs_init_nfspagecache(void);
266bee88	172	extern void nfs_destroy_nfspagecache(void);
f7b422b1	173	extern int __init nfs_init_readpagecache(void);
266bee88	174	extern void nfs_destroy_readpagecache(void);
f7b422b1	175	extern int __init nfs_init_writepagecache(void);
266bee88	176	extern void nfs_destroy_writepagecache(void);
f7b422b1	177
f7b422b1	178	extern int __init nfs_init_directcache(void);
266bee88	179	extern void nfs_destroy_directcache(void);
f7b422b1 DH	180
f7b422b1 DH	181	/* nfs2xdr.c */
7d4e2747	182	extern int nfs_stat_to_errno(int);
f7b422b1	183	extern struct rpc_procinfo nfs_procedures[];
0dbb4c67	184	extern __be32 * nfs_decode_dirent(__be32 , struct nfs_entry , int);
f7b422b1 DH	185
	186	/* nfs3xdr.c */
	187	extern struct rpc_procinfo nfs3_procedures[];
0dbb4c67	188	extern __be32 nfs3_decode_dirent(__be32 , struct nfs_entry *, int);
f7b422b1 DH	189
f7b422b1 DH	190	/* nfs4xdr.c */
7d4e2747	191	#ifdef CONFIG_NFS_V4
0dbb4c67	192	extern __be32 nfs4_decode_dirent(__be32 p, struct nfs_entry *entry, int plus);
7d4e2747	193	#endif
2449ea2e AB	194	#ifdef CONFIG_NFS_V4_1
	195	extern const u32 nfs41_maxread_overhead;
	196	extern const u32 nfs41_maxwrite_overhead;
	197	#endif
f7b422b1 DH	198
f7b422b1 DH	199	/* nfs4proc.c */
d75d5414	200	#ifdef CONFIG_NFS_V4
f7b422b1	201	extern struct rpc_procinfo nfs4_procedures[];
d75d5414	202	#endif
f7b422b1	203
7fe5c398 TM	204	/* proc.c */
	205	void nfs_close_context(struct nfs_open_context *ctx, int is_sync);
	206
979df72e TM	207	/* dir.c */
	208	extern int nfs_access_cache_shrinker(int nr_to_scan, gfp_t gfp_mask);
	209
f7b422b1	210	/* inode.c */
5746006f	211	extern struct workqueue_struct *nfsiod_workqueue;
f7b422b1 DH	212	extern struct inode nfs_alloc_inode(struct super_block sb);
f7b422b1 DH	213	extern void nfs_destroy_inode(struct inode *);
a9185b41	214	extern int nfs_write_inode(struct inode , struct writeback_control );
f7b422b1 DH	215	extern void nfs_clear_inode(struct inode *);
	216	#ifdef CONFIG_NFS_V4
	217	extern void nfs4_clear_inode(struct inode *);
	218	#endif
f41f7418	219	void nfs_zap_acl_cache(struct inode *inode);
72cb77f4	220	extern int nfs_wait_bit_killable(void *word);
f7b422b1 DH	221
f7b422b1 DH	222	/* super.c */
54ceac45	223	extern struct file_system_type nfs_xdev_fs_type;
f7b422b1	224	#ifdef CONFIG_NFS_V4
54ceac45 DH	225	extern struct file_system_type nfs4_xdev_fs_type;
54ceac45 DH	226	extern struct file_system_type nfs4_referral_fs_type;
f7b422b1	227	#endif
4ebd9ab3	228
f7b422b1	229	extern struct rpc_stat nfs_rpcstat;
4ebd9ab3	230
f7b422b1 DH	231	extern int __init register_nfs_fs(void);
f7b422b1 DH	232	extern void __exit unregister_nfs_fs(void);
1daef0a8 TM	233	extern void nfs_sb_active(struct super_block *sb);
1daef0a8 TM	234	extern void nfs_sb_deactive(struct super_block *sb);
f7b422b1 DH	235
f7b422b1 DH	236	/* namespace.c */
54ceac45 DH	237	extern char nfs_path(const char base,
	238	const struct dentry *droot,
	239	const struct dentry *dentry,
f7b422b1 DH	240	char *buffer, ssize_t buflen);
f7b422b1 DH	241
54ceac45 DH	242	/* getroot.c */
54ceac45 DH	243	extern struct dentry nfs_get_root(struct super_block , struct nfs_fh *);
7d4e2747	244	#ifdef CONFIG_NFS_V4
54ceac45 DH	245	extern struct dentry nfs4_get_root(struct super_block , struct nfs_fh *);
54ceac45 DH	246
815409d2	247	extern int nfs4_get_rootfh(struct nfs_server server, struct nfs_fh mntfh);
7d4e2747	248	#endif
f7b422b1	249
f11c88af AA	250	/* read.c */
	251	extern void nfs_read_prepare(struct rpc_task task, void calldata);
	252
def6ed7e AA	253	/* write.c */
def6ed7e AA	254	extern void nfs_write_prepare(struct rpc_task task, void calldata);
074cc1de TM	255	#ifdef CONFIG_MIGRATION
	256	extern int nfs_migrate_page(struct address_space *,
	257	struct page , struct page );
	258	#else
	259	#define nfs_migrate_page NULL
	260	#endif
def6ed7e	261
cccef3b9 AA	262	/* nfs4proc.c */
	263	extern int _nfs4_call_sync(struct nfs_server *server,
	264	struct rpc_message *msg,
	265	struct nfs4_sequence_args *args,
	266	struct nfs4_sequence_res *res,
	267	int cache_reply);
	268	extern int _nfs4_call_sync_session(struct nfs_server *server,
	269	struct rpc_message *msg,
	270	struct nfs4_sequence_args *args,
	271	struct nfs4_sequence_res *res,
	272	int cache_reply);
	273
f7b422b1 DH	274	/*
	275	* Determine the device name as a string
	276	*/
	277	static inline char nfs_devname(const struct vfsmount mnt_parent,
54ceac45 DH	278	const struct dentry *dentry,
54ceac45 DH	279	char *buffer, ssize_t buflen)
f7b422b1	280	{
54ceac45 DH	281	return nfs_path(mnt_parent->mnt_devname, mnt_parent->mnt_root,
54ceac45 DH	282	dentry, buffer, buflen);
f7b422b1 DH	283	}
	284
	285	/*
	286	* Determine the actual block size (and log2 thereof)
	287	*/
	288	static inline
	289	unsigned long nfs_block_bits(unsigned long bsize, unsigned char *nrbitsp)
	290	{
	291	/* make sure blocksize is a power of two */
	292	if ((bsize & (bsize - 1)) \|\| nrbitsp) {
	293	unsigned char nrbits;
	294
	295	for (nrbits = 31; nrbits && !(bsize & (1 << nrbits)); nrbits--)
	296	;
	297	bsize = 1 << nrbits;
	298	if (nrbitsp)
	299	*nrbitsp = nrbits;
	300	}
	301
	302	return bsize;
	303	}
	304
	305	/*
	306	* Calculate the number of 512byte blocks used.
	307	*/
9eaa67c6	308	static inline blkcnt_t nfs_calc_block_size(u64 tsize)
f7b422b1	309	{
9eaa67c6	310	blkcnt_t used = (tsize + 511) >> 9;
f7b422b1 DH	311	return (used > ULONG_MAX) ? ULONG_MAX : used;
	312	}
	313
	314	/*
	315	* Compute and set NFS server blocksize
	316	*/
	317	static inline
	318	unsigned long nfs_block_size(unsigned long bsize, unsigned char *nrbitsp)
	319	{
	320	if (bsize < NFS_MIN_FILE_IO_SIZE)
	321	bsize = NFS_DEF_FILE_IO_SIZE;
	322	else if (bsize >= NFS_MAX_FILE_IO_SIZE)
	323	bsize = NFS_MAX_FILE_IO_SIZE;
	324
	325	return nfs_block_bits(bsize, nrbitsp);
	326	}
	327
	328	/*
	329	* Determine the maximum file size for a superblock
	330	*/
	331	static inline
	332	void nfs_super_set_maxbytes(struct super_block *sb, __u64 maxfilesize)
	333	{
	334	sb->s_maxbytes = (loff_t)maxfilesize;
	335	if (sb->s_maxbytes > MAX_LFS_FILESIZE \|\| sb->s_maxbytes <= 0)
	336	sb->s_maxbytes = MAX_LFS_FILESIZE;
	337	}
49a70f27 TM	338
	339	/*
	340	* Determine the number of bytes of data the page contains
	341	*/
	342	static inline
	343	unsigned int nfs_page_length(struct page *page)
	344	{
	345	loff_t i_size = i_size_read(page->mapping->host);
	346
	347	if (i_size > 0) {
	348	pgoff_t end_index = (i_size - 1) >> PAGE_CACHE_SHIFT;
	349	if (page->index < end_index)
	350	return PAGE_CACHE_SIZE;
	351	if (page->index == end_index)
	352	return ((i_size - 1) & ~PAGE_CACHE_MASK) + 1;
	353	}
	354	return 0;
	355	}
8d5658c9 TM	356
	357	/*
	358	* Determine the number of pages in an array of length 'len' and
	359	* with a base offset of 'base'
	360	*/
	361	static inline
	362	unsigned int nfs_page_array_len(unsigned int base, size_t len)
	363	{
	364	return ((unsigned long)len + (unsigned long)base +
	365	PAGE_SIZE - 1) >> PAGE_SHIFT;
	366	}
0110ee15 TM	367
	368	/*
	369	* Helper for restarting RPC calls in the possible presence of NFSv4.1
	370	* sessions.
	371	*/
	372	static inline void nfs_restart_rpc(struct rpc_task task, const struct nfs_client clp)
	373	{
	374	if (nfs4_has_session(clp))
	375	rpc_restart_call_prepare(task);
	376	else
	377	rpc_restart_call(task);
	378	}