[net-next-2.6.git] / fs / ceph / mds_client.h

#ifndef _FS_CEPH_MDS_CLIENT_H
#define _FS_CEPH_MDS_CLIENT_H

#include <linux/completion.h>
#include <linux/kref.h>
#include <linux/list.h>
#include <linux/mutex.h>
#include <linux/rbtree.h>
#include <linux/spinlock.h>

#include <linux/ceph/types.h>
#include <linux/ceph/messenger.h>
#include <linux/ceph/mdsmap.h>

/*
 * Some lock dependencies:
 *
 * session->s_mutex
 *         mdsc->mutex
 *
 *         mdsc->snap_rwsem
 *
 *         inode->i_lock
 *                 mdsc->snap_flush_lock
 *                 mdsc->cap_delay_lock
 *
 */

struct ceph_fs_client;
struct ceph_cap;

/*
 * parsed info about a single inode.  pointers are into the encoded
 * on-wire structures within the mds reply message payload.
 */
struct ceph_mds_reply_info_in {
	struct ceph_mds_reply_inode *in;
	u32 symlink_len;
	char *symlink;
	u32 xattr_len;
	char *xattr_data;
};

/*
 * parsed info about an mds reply, including information about the
 * target inode and/or its parent directory and dentry, and directory
 * contents (for readdir results).
 */
struct ceph_mds_reply_info_parsed {
	struct ceph_mds_reply_head    *head;

	struct ceph_mds_reply_info_in diri, targeti;
	struct ceph_mds_reply_dirfrag *dirfrag;
	char                          *dname;
	u32                           dname_len;
	struct ceph_mds_reply_lease   *dlease;

	struct ceph_mds_reply_dirfrag *dir_dir;
	int                           dir_nr;
	char                          **dir_dname;
	u32                           *dir_dname_len;
	struct ceph_mds_reply_lease   **dir_dlease;
	struct ceph_mds_reply_info_in *dir_in;
	u8                            dir_complete, dir_end;

	/* encoded blob describing snapshot contexts for certain
	   operations (e.g., open) */
	void *snapblob;
	int snapblob_len;
};


/*
 * cap releases are batched and sent to the MDS en masse.
 */
#define CEPH_CAPS_PER_RELEASE ((PAGE_CACHE_SIZE -			\
				sizeof(struct ceph_mds_cap_release)) /	\
			       sizeof(struct ceph_mds_cap_item))


/*
 * state associated with each MDS<->client session
 */
enum {
	CEPH_MDS_SESSION_NEW = 1,
	CEPH_MDS_SESSION_OPENING = 2,
	CEPH_MDS_SESSION_OPEN = 3,
	CEPH_MDS_SESSION_HUNG = 4,
	CEPH_MDS_SESSION_CLOSING = 5,
	CEPH_MDS_SESSION_RESTARTING = 6,
	CEPH_MDS_SESSION_RECONNECTING = 7,
};

struct ceph_mds_session {
	struct ceph_mds_client *s_mdsc;
	int               s_mds;
	int               s_state;
	unsigned long     s_ttl;      /* time until mds kills us */
	u64               s_seq;      /* incoming msg seq # */
	struct mutex      s_mutex;    /* serialize session messages */

	struct ceph_connection s_con;

	struct ceph_authorizer *s_authorizer;
	void             *s_authorizer_buf, *s_authorizer_reply_buf;
	size_t            s_authorizer_buf_len, s_authorizer_reply_buf_len;

	/* protected by s_cap_lock */
	spinlock_t        s_cap_lock;
	u32               s_cap_gen;  /* inc each time we get mds stale msg */
	unsigned long     s_cap_ttl;  /* when session caps expire */
	struct list_head  s_caps;     /* all caps issued by this session */
	int               s_nr_caps, s_trim_caps;
	int               s_num_cap_releases;
	struct list_head  s_cap_releases; /* waiting cap_release messages */
	struct list_head  s_cap_releases_done; /* ready to send */
	struct ceph_cap  *s_cap_iterator;

	/* protected by mutex */
	struct list_head  s_cap_flushing;     /* inodes w/ flushing caps */
	struct list_head  s_cap_snaps_flushing;
	unsigned long     s_renew_requested; /* last time we sent a renew req */
	u64               s_renew_seq;

	atomic_t          s_ref;
	struct list_head  s_waiting;  /* waiting requests */
	struct list_head  s_unsafe;   /* unsafe requests */
};

/*
 * modes of choosing which MDS to send a request to
 */
enum {
	USE_ANY_MDS,
	USE_RANDOM_MDS,
	USE_AUTH_MDS,   /* prefer authoritative mds for this metadata item */
};

struct ceph_mds_request;
struct ceph_mds_client;

/*
 * request completion callback
 */
typedef void (*ceph_mds_request_callback_t) (struct ceph_mds_client *mdsc,
					     struct ceph_mds_request *req);

/*
 * an in-flight mds request
 */
struct ceph_mds_request {
	u64 r_tid;                   /* transaction id */
	struct rb_node r_node;
	struct ceph_mds_client *r_mdsc;

	int r_op;                    /* mds op code */
	int r_mds;

	/* operation on what? */
	struct inode *r_inode;              /* arg1 */
	struct dentry *r_dentry;            /* arg1 */
	struct dentry *r_old_dentry;        /* arg2: rename from or link from */
	char *r_path1, *r_path2;
	struct ceph_vino r_ino1, r_ino2;

	struct inode *r_locked_dir; /* dir (if any) i_mutex locked by vfs */
	struct inode *r_target_inode;       /* resulting inode */

	struct mutex r_fill_mutex;

	union ceph_mds_request_args r_args;
	int r_fmode;        /* file mode, if expecting cap */

	/* for choosing which mds to send this request to */
	int r_direct_mode;
	u32 r_direct_hash;      /* choose dir frag based on this dentry hash */
	bool r_direct_is_hash;  /* true if r_direct_hash is valid */

	/* data payload is used for xattr ops */
	struct page **r_pages;
	int r_num_pages;
	int r_data_len;

	/* what caps shall we drop? */
	int r_inode_drop, r_inode_unless;
	int r_dentry_drop, r_dentry_unless;
	int r_old_dentry_drop, r_old_dentry_unless;
	struct inode *r_old_inode;
	int r_old_inode_drop, r_old_inode_unless;

	struct ceph_msg  *r_request;  /* original request */
	int r_request_release_offset;
	struct ceph_msg  *r_reply;
	struct ceph_mds_reply_info_parsed r_reply_info;
	int r_err;
	bool r_aborted;

	unsigned long r_timeout;  /* optional.  jiffies */
	unsigned long r_started;  /* start time to measure timeout against */
	unsigned long r_request_started; /* start time for mds request only,
					    used to measure lease durations */

	/* link unsafe requests to parent directory, for fsync */
	struct inode	*r_unsafe_dir;
	struct list_head r_unsafe_dir_item;

	struct ceph_mds_session *r_session;

	int               r_attempts;   /* resend attempts */
	int               r_num_fwd;    /* number of forward attempts */
	int               r_resend_mds; /* mds to resend to next, if any*/
	u32               r_sent_on_mseq; /* cap mseq request was sent at*/

	struct kref       r_kref;
	struct list_head  r_wait;
	struct completion r_completion;
	struct completion r_safe_completion;
	ceph_mds_request_callback_t r_callback;
	struct list_head  r_unsafe_item;  /* per-session unsafe list item */
	bool		  r_got_unsafe, r_got_safe, r_got_result;

	bool              r_did_prepopulate;
	u32               r_readdir_offset;

	struct ceph_cap_reservation r_caps_reservation;
	int r_num_caps;
};

/*
 * mds client state
 */
struct ceph_mds_client {
	struct ceph_fs_client  *fsc;
	struct mutex            mutex;         /* all nested structures */

	struct ceph_mdsmap      *mdsmap;
	struct completion       safe_umount_waiters;
	wait_queue_head_t       session_close_wq;
	struct list_head        waiting_for_map;

	struct ceph_mds_session **sessions;    /* NULL for mds if no session */
	int                     max_sessions;  /* len of s_mds_sessions */
	int                     stopping;      /* true if shutting down */

	/*
	 * snap_rwsem will cover cap linkage into snaprealms, and
	 * realm snap contexts.  (later, we can do per-realm snap
	 * contexts locks..)  the empty list contains realms with no
	 * references (implying they contain no inodes with caps) that
	 * should be destroyed.
	 */
	struct rw_semaphore     snap_rwsem;
	struct rb_root          snap_realms;
	struct list_head        snap_empty;
	spinlock_t              snap_empty_lock;  /* protect snap_empty */

	u64                    last_tid;      /* most recent mds request */
	struct rb_root         request_tree;  /* pending mds requests */
	struct delayed_work    delayed_work;  /* delayed work */
	unsigned long    last_renew_caps;  /* last time we renewed our caps */
	struct list_head cap_delay_list;   /* caps with delayed release */
	spinlock_t       cap_delay_lock;   /* protects cap_delay_list */
	struct list_head snap_flush_list;  /* cap_snaps ready to flush */
	spinlock_t       snap_flush_lock;

	u64               cap_flush_seq;
	struct list_head  cap_dirty;        /* inodes with dirty caps */
	int               num_cap_flushing; /* # caps we are flushing */
	spinlock_t        cap_dirty_lock;   /* protects above items */
	wait_queue_head_t cap_flushing_wq;

	/*
	 * Cap reservations
	 *
	 * Maintain a global pool of preallocated struct ceph_caps, referenced
	 * by struct ceph_caps_reservations.  This ensures that we preallocate
	 * memory needed to successfully process an MDS response.  (If an MDS
	 * sends us cap information and we fail to process it, we will have
	 * problems due to the client and MDS being out of sync.)
	 *
	 * Reservations are 'owned' by a ceph_cap_reservation context.
	 */
	spinlock_t	caps_list_lock;
	struct		list_head caps_list; /* unused (reserved or
						unreserved) */
	int		caps_total_count;    /* total caps allocated */
	int		caps_use_count;      /* in use */
	int		caps_reserve_count;  /* unused, reserved */
	int		caps_avail_count;    /* unused, unreserved */
	int		caps_min_count;      /* keep at least this many
						(unreserved) */
	spinlock_t	  dentry_lru_lock;
	struct list_head  dentry_lru;
	int		  num_dentry;
};

extern const char *ceph_mds_op_name(int op);

extern struct ceph_mds_session *
__ceph_lookup_mds_session(struct ceph_mds_client *, int mds);

static inline struct ceph_mds_session *
ceph_get_mds_session(struct ceph_mds_session *s)
{
	atomic_inc(&s->s_ref);
	return s;
}

extern void ceph_put_mds_session(struct ceph_mds_session *s);

extern int ceph_send_msg_mds(struct ceph_mds_client *mdsc,
			     struct ceph_msg *msg, int mds);

extern int ceph_mdsc_init(struct ceph_fs_client *fsc);
extern void ceph_mdsc_close_sessions(struct ceph_mds_client *mdsc);
extern void ceph_mdsc_destroy(struct ceph_fs_client *fsc);

extern void ceph_mdsc_sync(struct ceph_mds_client *mdsc);

extern void ceph_mdsc_lease_release(struct ceph_mds_client *mdsc,
				    struct inode *inode,
				    struct dentry *dn, int mask);

extern void ceph_invalidate_dir_request(struct ceph_mds_request *req);

extern struct ceph_mds_request *
ceph_mdsc_create_request(struct ceph_mds_client *mdsc, int op, int mode);
extern void ceph_mdsc_submit_request(struct ceph_mds_client *mdsc,
				     struct ceph_mds_request *req);
extern int ceph_mdsc_do_request(struct ceph_mds_client *mdsc,
				struct inode *dir,
				struct ceph_mds_request *req);
static inline void ceph_mdsc_get_request(struct ceph_mds_request *req)
{
	kref_get(&req->r_kref);
}
extern void ceph_mdsc_release_request(struct kref *kref);
static inline void ceph_mdsc_put_request(struct ceph_mds_request *req)
{
	kref_put(&req->r_kref, ceph_mdsc_release_request);
}

extern int ceph_add_cap_releases(struct ceph_mds_client *mdsc,
				 struct ceph_mds_session *session);
extern void ceph_send_cap_releases(struct ceph_mds_client *mdsc,
				   struct ceph_mds_session *session);

extern void ceph_mdsc_pre_umount(struct ceph_mds_client *mdsc);

extern char *ceph_mdsc_build_path(struct dentry *dentry, int *plen, u64 *base,
				  int stop_on_nosnap);

extern void __ceph_mdsc_drop_dentry_lease(struct dentry *dentry);
extern void ceph_mdsc_lease_send_msg(struct ceph_mds_session *session,
				     struct inode *inode,
				     struct dentry *dentry, char action,
				     u32 seq);

extern void ceph_mdsc_handle_map(struct ceph_mds_client *mdsc,
				 struct ceph_msg *msg);

extern void ceph_mdsc_open_export_target_sessions(struct ceph_mds_client *mdsc,
					  struct ceph_mds_session *session);

#endif
Commit	Line	Data
2f2dc053 SW	1	#ifndef _FS_CEPH_MDS_CLIENT_H
	2	#define _FS_CEPH_MDS_CLIENT_H
	3
	4	#include <linux/completion.h>
153c8e6b	5	#include <linux/kref.h>
2f2dc053 SW	6	#include <linux/list.h>
2f2dc053 SW	7	#include <linux/mutex.h>
44ca18f2	8	#include <linux/rbtree.h>
2f2dc053 SW	9	#include <linux/spinlock.h>
2f2dc053 SW	10
3d14c5d2 YS	11	#include <linux/ceph/types.h>
	12	#include <linux/ceph/messenger.h>
	13	#include <linux/ceph/mdsmap.h>
2f2dc053 SW	14
	15	/*
	16	* Some lock dependencies:
	17	*
	18	* session->s_mutex
	19	* mdsc->mutex
	20	*
	21	* mdsc->snap_rwsem
	22	*
	23	* inode->i_lock
	24	* mdsc->snap_flush_lock
	25	* mdsc->cap_delay_lock
	26	*
	27	*/
	28
3d14c5d2	29	struct ceph_fs_client;
2f2dc053 SW	30	struct ceph_cap;
	31
	32	/*
	33	* parsed info about a single inode. pointers are into the encoded
	34	* on-wire structures within the mds reply message payload.
	35	*/
	36	struct ceph_mds_reply_info_in {
	37	struct ceph_mds_reply_inode *in;
	38	u32 symlink_len;
	39	char *symlink;
	40	u32 xattr_len;
	41	char *xattr_data;
	42	};
	43
	44	/*
	45	* parsed info about an mds reply, including information about the
	46	* target inode and/or its parent directory and dentry, and directory
	47	* contents (for readdir results).
	48	*/
	49	struct ceph_mds_reply_info_parsed {
	50	struct ceph_mds_reply_head *head;
	51
	52	struct ceph_mds_reply_info_in diri, targeti;
	53	struct ceph_mds_reply_dirfrag *dirfrag;
	54	char *dname;
	55	u32 dname_len;
	56	struct ceph_mds_reply_lease *dlease;
	57
	58	struct ceph_mds_reply_dirfrag *dir_dir;
	59	int dir_nr;
	60	char **dir_dname;
	61	u32 *dir_dname_len;
	62	struct ceph_mds_reply_lease **dir_dlease;
	63	struct ceph_mds_reply_info_in *dir_in;
	64	u8 dir_complete, dir_end;
	65
	66	/* encoded blob describing snapshot contexts for certain
	67	operations (e.g., open) */
	68	void *snapblob;
	69	int snapblob_len;
	70	};
	71
	72
	73	/*
	74	* cap releases are batched and sent to the MDS en masse.
	75	*/
	76	#define CEPH_CAPS_PER_RELEASE ((PAGE_CACHE_SIZE - \
	77	sizeof(struct ceph_mds_cap_release)) / \
	78	sizeof(struct ceph_mds_cap_item))
	79
	80
	81	/*
	82	* state associated with each MDS<->client session
	83	*/
	84	enum {
	85	CEPH_MDS_SESSION_NEW = 1,
	86	CEPH_MDS_SESSION_OPENING = 2,
	87	CEPH_MDS_SESSION_OPEN = 3,
	88	CEPH_MDS_SESSION_HUNG = 4,
	89	CEPH_MDS_SESSION_CLOSING = 5,
	90	CEPH_MDS_SESSION_RESTARTING = 6,
	91	CEPH_MDS_SESSION_RECONNECTING = 7,
	92	};
	93
94	struct ceph_mds_session {
95	struct ceph_mds_client *s_mdsc;
96	int s_mds;
97	int s_state;
98	unsigned long s_ttl; /* time until mds kills us */
99	u64 s_seq; /* incoming msg seq # */
100	struct mutex s_mutex; /* serialize session messages */
101
102	struct ceph_connection s_con;
103
4e7a5dcd SW	104	struct ceph_authorizer *s_authorizer;
	105	void s_authorizer_buf, s_authorizer_reply_buf;
	106	size_t s_authorizer_buf_len, s_authorizer_reply_buf_len;
	107
2f2dc053 SW	108	/* protected by s_cap_lock */
	109	spinlock_t s_cap_lock;
	110	u32 s_cap_gen; /* inc each time we get mds stale msg */
	111	unsigned long s_cap_ttl; /* when session caps expire */
	112	struct list_head s_caps; /* all caps issued by this session */
	113	int s_nr_caps, s_trim_caps;
	114	int s_num_cap_releases;
	115	struct list_head s_cap_releases; /* waiting cap_release messages */
	116	struct list_head s_cap_releases_done; /* ready to send */
7c1332b8	117	struct ceph_cap *s_cap_iterator;
2f2dc053 SW	118
	119	/* protected by mutex */
	120	struct list_head s_cap_flushing; /* inodes w/ flushing caps */
	121	struct list_head s_cap_snaps_flushing;
	122	unsigned long s_renew_requested; /* last time we sent a renew req */
	123	u64 s_renew_seq;
	124
	125	atomic_t s_ref;
	126	struct list_head s_waiting; /* waiting requests */
	127	struct list_head s_unsafe; /* unsafe requests */
	128	};
	129
	130	/*
	131	* modes of choosing which MDS to send a request to
	132	*/
	133	enum {
	134	USE_ANY_MDS,
	135	USE_RANDOM_MDS,
	136	USE_AUTH_MDS, /* prefer authoritative mds for this metadata item */
	137	};
	138
	139	struct ceph_mds_request;
	140	struct ceph_mds_client;
	141
	142	/*
	143	* request completion callback
	144	*/
	145	typedef void (ceph_mds_request_callback_t) (struct ceph_mds_client mdsc,
	146	struct ceph_mds_request *req);
	147
	148	/*
	149	* an in-flight mds request
	150	*/
	151	struct ceph_mds_request {
	152	u64 r_tid; /* transaction id */
44ca18f2	153	struct rb_node r_node;
37151668	154	struct ceph_mds_client *r_mdsc;
2f2dc053 SW	155
	156	int r_op; /* mds op code */
	157	int r_mds;
	158
	159	/* operation on what? */
	160	struct inode r_inode; / arg1 */
	161	struct dentry r_dentry; / arg1 */
	162	struct dentry r_old_dentry; / arg2: rename from or link from */
	163	char r_path1, r_path2;
	164	struct ceph_vino r_ino1, r_ino2;
	165
	166	struct inode r_locked_dir; / dir (if any) i_mutex locked by vfs */
	167	struct inode r_target_inode; / resulting inode */
	168
b4556396 SW	169	struct mutex r_fill_mutex;
b4556396 SW	170
2f2dc053 SW	171	union ceph_mds_request_args r_args;
	172	int r_fmode; /* file mode, if expecting cap */
	173
	174	/* for choosing which mds to send this request to */
	175	int r_direct_mode;
	176	u32 r_direct_hash; /* choose dir frag based on this dentry hash */
	177	bool r_direct_is_hash; /* true if r_direct_hash is valid */
	178
	179	/* data payload is used for xattr ops */
	180	struct page **r_pages;
	181	int r_num_pages;
	182	int r_data_len;
	183
	184	/* what caps shall we drop? */
	185	int r_inode_drop, r_inode_unless;
	186	int r_dentry_drop, r_dentry_unless;
	187	int r_old_dentry_drop, r_old_dentry_unless;
	188	struct inode *r_old_inode;
	189	int r_old_inode_drop, r_old_inode_unless;
	190
	191	struct ceph_msg r_request; / original request */
e979cf50	192	int r_request_release_offset;
2f2dc053 SW	193	struct ceph_msg *r_reply;
	194	struct ceph_mds_reply_info_parsed r_reply_info;
	195	int r_err;
5b1daecd	196	bool r_aborted;
2f2dc053 SW	197
	198	unsigned long r_timeout; /* optional. jiffies */
	199	unsigned long r_started; /* start time to measure timeout against */
	200	unsigned long r_request_started; /* start time for mds request only,
	201	used to measure lease durations */
	202
	203	/* link unsafe requests to parent directory, for fsync */
	204	struct inode *r_unsafe_dir;
	205	struct list_head r_unsafe_dir_item;
	206
	207	struct ceph_mds_session *r_session;
	208
	209	int r_attempts; /* resend attempts */
	210	int r_num_fwd; /* number of forward attempts */
2f2dc053	211	int r_resend_mds; /* mds to resend to next, if any*/
e55b71f8	212	u32 r_sent_on_mseq; /* cap mseq request was sent at*/
2f2dc053	213
153c8e6b	214	struct kref r_kref;
2f2dc053 SW	215	struct list_head r_wait;
	216	struct completion r_completion;
	217	struct completion r_safe_completion;
	218	ceph_mds_request_callback_t r_callback;
	219	struct list_head r_unsafe_item; /* per-session unsafe list item */
e1518c7c	220	bool r_got_unsafe, r_got_safe, r_got_result;
2f2dc053 SW	221
	222	bool r_did_prepopulate;
	223	u32 r_readdir_offset;
	224
	225	struct ceph_cap_reservation r_caps_reservation;
	226	int r_num_caps;
	227	};
	228
	229	/*
	230	* mds client state
	231	*/
	232	struct ceph_mds_client {
3d14c5d2	233	struct ceph_fs_client *fsc;
2f2dc053 SW	234	struct mutex mutex; /* all nested structures */
	235
	236	struct ceph_mdsmap *mdsmap;
f3c60c59 SW	237	struct completion safe_umount_waiters;
f3c60c59 SW	238	wait_queue_head_t session_close_wq;
2f2dc053 SW	239	struct list_head waiting_for_map;
	240
	241	struct ceph_mds_session *sessions; / NULL for mds if no session */
	242	int max_sessions; /* len of s_mds_sessions */
	243	int stopping; /* true if shutting down */
	244
	245	/*
	246	* snap_rwsem will cover cap linkage into snaprealms, and
	247	* realm snap contexts. (later, we can do per-realm snap
	248	* contexts locks..) the empty list contains realms with no
	249	* references (implying they contain no inodes with caps) that
	250	* should be destroyed.
	251	*/
	252	struct rw_semaphore snap_rwsem;
a105f00c	253	struct rb_root snap_realms;
2f2dc053 SW	254	struct list_head snap_empty;
	255	spinlock_t snap_empty_lock; /* protect snap_empty */
	256
	257	u64 last_tid; /* most recent mds request */
44ca18f2	258	struct rb_root request_tree; /* pending mds requests */
2f2dc053 SW	259	struct delayed_work delayed_work; /* delayed work */
	260	unsigned long last_renew_caps; /* last time we renewed our caps */
	261	struct list_head cap_delay_list; /* caps with delayed release */
	262	spinlock_t cap_delay_lock; /* protects cap_delay_list */
	263	struct list_head snap_flush_list; /* cap_snaps ready to flush */
	264	spinlock_t snap_flush_lock;
	265
	266	u64 cap_flush_seq;
	267	struct list_head cap_dirty; /* inodes with dirty caps */
	268	int num_cap_flushing; /* # caps we are flushing */
	269	spinlock_t cap_dirty_lock; /* protects above items */
	270	wait_queue_head_t cap_flushing_wq;
	271
37151668 YS	272	/*
	273	* Cap reservations
	274	*
	275	* Maintain a global pool of preallocated struct ceph_caps, referenced
	276	* by struct ceph_caps_reservations. This ensures that we preallocate
	277	* memory needed to successfully process an MDS response. (If an MDS
	278	* sends us cap information and we fail to process it, we will have
	279	* problems due to the client and MDS being out of sync.)
	280	*
	281	* Reservations are 'owned' by a ceph_cap_reservation context.
	282	*/
	283	spinlock_t caps_list_lock;
	284	struct list_head caps_list; /* unused (reserved or
	285	unreserved) */
	286	int caps_total_count; /* total caps allocated */
	287	int caps_use_count; /* in use */
	288	int caps_reserve_count; /* unused, reserved */
	289	int caps_avail_count; /* unused, unreserved */
	290	int caps_min_count; /* keep at least this many
	291	(unreserved) */
2f2dc053 SW	292	spinlock_t dentry_lru_lock;
	293	struct list_head dentry_lru;
	294	int num_dentry;
	295	};
	296
	297	extern const char *ceph_mds_op_name(int op);
	298
	299	extern struct ceph_mds_session *
	300	__ceph_lookup_mds_session(struct ceph_mds_client *, int mds);
	301
	302	static inline struct ceph_mds_session *
	303	ceph_get_mds_session(struct ceph_mds_session *s)
	304	{
	305	atomic_inc(&s->s_ref);
	306	return s;
	307	}
	308
	309	extern void ceph_put_mds_session(struct ceph_mds_session *s);
	310
	311	extern int ceph_send_msg_mds(struct ceph_mds_client *mdsc,
	312	struct ceph_msg *msg, int mds);
	313
3d14c5d2	314	extern int ceph_mdsc_init(struct ceph_fs_client *fsc);
2f2dc053	315	extern void ceph_mdsc_close_sessions(struct ceph_mds_client *mdsc);
3d14c5d2	316	extern void ceph_mdsc_destroy(struct ceph_fs_client *fsc);
2f2dc053 SW	317
	318	extern void ceph_mdsc_sync(struct ceph_mds_client *mdsc);
	319
	320	extern void ceph_mdsc_lease_release(struct ceph_mds_client *mdsc,
	321	struct inode *inode,
	322	struct dentry *dn, int mask);
	323
167c9e35 SW	324	extern void ceph_invalidate_dir_request(struct ceph_mds_request *req);
167c9e35 SW	325
2f2dc053 SW	326	extern struct ceph_mds_request *
	327	ceph_mdsc_create_request(struct ceph_mds_client *mdsc, int op, int mode);
	328	extern void ceph_mdsc_submit_request(struct ceph_mds_client *mdsc,
	329	struct ceph_mds_request *req);
	330	extern int ceph_mdsc_do_request(struct ceph_mds_client *mdsc,
	331	struct inode *dir,
	332	struct ceph_mds_request *req);
	333	static inline void ceph_mdsc_get_request(struct ceph_mds_request *req)
	334	{
153c8e6b SW	335	kref_get(&req->r_kref);
	336	}
	337	extern void ceph_mdsc_release_request(struct kref *kref);
	338	static inline void ceph_mdsc_put_request(struct ceph_mds_request *req)
	339	{
	340	kref_put(&req->r_kref, ceph_mdsc_release_request);
2f2dc053	341	}
2f2dc053	342
2b2300d6	343	extern int ceph_add_cap_releases(struct ceph_mds_client *mdsc,
ee6b272b	344	struct ceph_mds_session *session);
3d7ded4d SW	345	extern void ceph_send_cap_releases(struct ceph_mds_client *mdsc,
	346	struct ceph_mds_session *session);
	347
2f2dc053 SW	348	extern void ceph_mdsc_pre_umount(struct ceph_mds_client *mdsc);
	349
	350	extern char ceph_mdsc_build_path(struct dentry dentry, int plen, u64 base,
	351	int stop_on_nosnap);
	352
	353	extern void __ceph_mdsc_drop_dentry_lease(struct dentry *dentry);
	354	extern void ceph_mdsc_lease_send_msg(struct ceph_mds_session *session,
	355	struct inode *inode,
	356	struct dentry *dentry, char action,
	357	u32 seq);
	358
	359	extern void ceph_mdsc_handle_map(struct ceph_mds_client *mdsc,
	360	struct ceph_msg *msg);
	361
154f42c2 SW	362	extern void ceph_mdsc_open_export_target_sessions(struct ceph_mds_client *mdsc,
	363	struct ceph_mds_session *session);
	364
2f2dc053	365	#endif