[mirror_ubuntu-artful-kernel.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/refcount.h>

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

/*
 * Some lock dependencies:
 *
 * session->s_mutex
 *         mdsc->mutex
 *
 *         mdsc->snap_rwsem
 *
 *         ci->i_ceph_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;
	struct ceph_dir_layout dir_layout;
	u32 symlink_len;
	char *symlink;
	u32 xattr_len;
	char *xattr_data;
	u64 inline_version;
	u32 inline_len;
	char *inline_data;
	u32 pool_ns_len;
	char *pool_ns_data;
};

struct ceph_mds_reply_dir_entry {
	char                          *name;
	u32                           name_len;
	struct ceph_mds_reply_lease   *lease;
	struct ceph_mds_reply_info_in inode;
	loff_t			      offset;
};

/*
 * parsed info about an mds reply, including information about
 * either: 1) the target inode and/or its parent directory and dentry,
 * and directory contents (for readdir results), or
 * 2) the file range lock info (for fcntl F_GETLK results).
 */
struct ceph_mds_reply_info_parsed {
	struct ceph_mds_reply_head    *head;

	/* trace */
	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;

	/* extra */
	union {
		/* for fcntl F_GETLK results */
		struct ceph_filelock *filelock_reply;

		/* for readdir results */
		struct {
			struct ceph_mds_reply_dirfrag *dir_dir;
			size_t			      dir_buf_size;
			int                           dir_nr;
			bool			      dir_end;
			bool			      dir_complete;
			bool			      hash_order;
			bool			      offset_hash;
			struct ceph_mds_reply_dir_entry  *dir_entries;
		};

		/* for create results */
		struct {
			bool has_create_ino;
			u64 ino;
		};
	};

	/* 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.
 *
 * Account for per-message overhead of mds_cap_release header
 * and __le32 for osd epoch barrier trailing field.
 */
#define CEPH_CAPS_PER_RELEASE ((PAGE_SIZE - sizeof(u32) -		\
				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,
	CEPH_MDS_SESSION_REJECTED = 8,
};

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_auth_handshake s_auth;

	/* protected by s_gen_ttl_lock */
	spinlock_t        s_gen_ttl_lock;
	u32               s_cap_gen;  /* inc each time we get mds stale msg */
	unsigned long     s_cap_ttl;  /* when session caps expire */

	/* protected by s_cap_lock */
	spinlock_t        s_cap_lock;
	struct list_head  s_caps;     /* all caps issued by this session */
	int               s_nr_caps, s_trim_caps;
	int               s_num_cap_releases;
	int		  s_cap_reconnect;
	int		  s_readonly;
	struct list_head  s_cap_releases; /* waiting cap_release messages */
	struct ceph_cap  *s_cap_iterator;

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

	refcount_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);
/*
 * wait for request completion callback
 */
typedef int (*ceph_mds_request_wait_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 */

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

	struct inode *r_parent;		    /* parent dir inode */
	struct inode *r_target_inode;       /* resulting inode */

#define CEPH_MDS_R_DIRECT_IS_HASH	(1) /* r_direct_hash is valid */
#define CEPH_MDS_R_ABORTED		(2) /* call was aborted */
#define CEPH_MDS_R_GOT_UNSAFE		(3) /* got an unsafe reply */
#define CEPH_MDS_R_GOT_SAFE		(4) /* got a safe reply */
#define CEPH_MDS_R_GOT_RESULT		(5) /* got a result */
#define CEPH_MDS_R_DID_PREPOPULATE	(6) /* prepopulated readdir */
#define CEPH_MDS_R_PARENT_LOCKED	(7) /* is r_parent->i_rwsem wlocked? */
	unsigned long	r_req_flags;

	struct mutex r_fill_mutex;

	union ceph_mds_request_args r_args;
	int r_fmode;        /* file mode, if expecting cap */
	kuid_t r_uid;
	kgid_t r_gid;
	struct timespec r_stamp;

	/* 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 */

	/* data payload is used for xattr ops */
	struct ceph_pagelist *r_pagelist;

	/* 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;
	struct page *r_locked_page;
	int r_err;

	unsigned long r_timeout;  /* optional.  jiffies, 0 is "wait forever" */
	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;

	/* unsafe requests that modify the target inode */
	struct list_head r_unsafe_target_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;
	ceph_mds_request_wait_callback_t r_wait_for_completion;
	struct list_head  r_unsafe_item;  /* per-session unsafe list item */

	long long	  r_dir_release_cnt;
	long long	  r_dir_ordered_cnt;
	int		  r_readdir_cache_idx;
	u32               r_readdir_offset;

	struct ceph_cap_reservation r_caps_reservation;
	int r_num_caps;
};

struct ceph_pool_perm {
	struct rb_node node;
	int perm;
	s64 pool;
	size_t pool_ns_len;
	char pool_ns[];
};

/*
 * 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;
	int 			mdsmap_err;

	struct ceph_mds_session **sessions;    /* NULL for mds if no session */
	atomic_t		num_sessions;
	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.
	 */
	u64			last_snap_seq;
	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 */
	u64                    oldest_tid;    /* oldest incomplete mds request,
						 excluding setfilelock requests */
	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               last_cap_flush_tid;
	struct list_head  cap_flush_list;
	struct list_head  cap_dirty;        /* inodes with dirty caps */
	struct list_head  cap_dirty_migrating; /* ...that are migration... */
	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;

	struct rw_semaphore     pool_perm_rwsem;
	struct rb_root		pool_perm_tree;
};

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)
{
	refcount_inc(&s->s_ref);
	return s;
}

extern const char *ceph_session_state_name(int 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_force_umount(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_invalidate_dir_request(struct ceph_mds_request *req);
extern int ceph_alloc_readdir_reply_buffer(struct ceph_mds_request *req,
					   struct inode *dir);
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 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_mdsmap(struct ceph_mds_client *mdsc,
				    struct ceph_msg *msg);
extern void ceph_mdsc_handle_fsmap(struct ceph_mds_client *mdsc,
				   struct ceph_msg *msg);

extern struct ceph_mds_session *
ceph_mdsc_open_export_target_session(struct ceph_mds_client *mdsc, int target);
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	9	#include <linux/spinlock.h>
3997c01d	10	#include <linux/refcount.h>
2f2dc053	11
3d14c5d2 YS	12	#include <linux/ceph/types.h>
	13	#include <linux/ceph/messenger.h>
	14	#include <linux/ceph/mdsmap.h>
6c4a1915	15	#include <linux/ceph/auth.h>
2f2dc053 SW	16
	17	/*
	18	* Some lock dependencies:
	19	*
	20	* session->s_mutex
	21	* mdsc->mutex
	22	*
	23	* mdsc->snap_rwsem
	24	*
be655596	25	* ci->i_ceph_lock
2f2dc053 SW	26	* mdsc->snap_flush_lock
	27	* mdsc->cap_delay_lock
	28	*
	29	*/
	30
3d14c5d2	31	struct ceph_fs_client;
2f2dc053 SW	32	struct ceph_cap;
	33
	34	/*
	35	* parsed info about a single inode. pointers are into the encoded
	36	* on-wire structures within the mds reply message payload.
	37	*/
	38	struct ceph_mds_reply_info_in {
	39	struct ceph_mds_reply_inode *in;
14303d20	40	struct ceph_dir_layout dir_layout;
2f2dc053 SW	41	u32 symlink_len;
	42	char *symlink;
	43	u32 xattr_len;
	44	char *xattr_data;
fb01d1f8 YZ	45	u64 inline_version;
	46	u32 inline_len;
	47	char *inline_data;
5ea5c5e0	48	u32 pool_ns_len;
779fe0fb	49	char *pool_ns_data;
2f2dc053 SW	50	};
2f2dc053 SW	51
2a5beea3 YZ	52	struct ceph_mds_reply_dir_entry {
	53	char *name;
	54	u32 name_len;
	55	struct ceph_mds_reply_lease *lease;
	56	struct ceph_mds_reply_info_in inode;
8974eebd	57	loff_t offset;
2a5beea3 YZ	58	};
2a5beea3 YZ	59
2f2dc053	60	/*
25933abd HS	61	* parsed info about an mds reply, including information about
	62	* either: 1) the target inode and/or its parent directory and dentry,
	63	* and directory contents (for readdir results), or
	64	* 2) the file range lock info (for fcntl F_GETLK results).
2f2dc053 SW	65	*/
	66	struct ceph_mds_reply_info_parsed {
	67	struct ceph_mds_reply_head *head;
	68
25933abd	69	/* trace */
2f2dc053 SW	70	struct ceph_mds_reply_info_in diri, targeti;
	71	struct ceph_mds_reply_dirfrag *dirfrag;
	72	char *dname;
	73	u32 dname_len;
	74	struct ceph_mds_reply_lease *dlease;
	75
25933abd HS	76	/* extra */
	77	union {
	78	/* for fcntl F_GETLK results */
	79	struct ceph_filelock *filelock_reply;
	80
	81	/* for readdir results */
	82	struct {
	83	struct ceph_mds_reply_dirfrag *dir_dir;
54008399	84	size_t dir_buf_size;
25933abd	85	int dir_nr;
f3c4ebe6	86	bool dir_end;
79162547	87	bool dir_complete;
f3c4ebe6	88	bool hash_order;
79162547	89	bool offset_hash;
2a5beea3	90	struct ceph_mds_reply_dir_entry *dir_entries;
25933abd	91	};
6e8575fa SL	92
	93	/* for create results */
	94	struct {
	95	bool has_create_ino;
	96	u64 ino;
	97	};
25933abd	98	};
2f2dc053 SW	99
	100	/* encoded blob describing snapshot contexts for certain
	101	operations (e.g., open) */
	102	void *snapblob;
	103	int snapblob_len;
	104	};
	105
	106
	107	/*
	108	* cap releases are batched and sent to the MDS en masse.
92475f05 JL	109	*
	110	* Account for per-message overhead of mds_cap_release header
	111	* and __le32 for osd epoch barrier trailing field.
2f2dc053	112	*/
92475f05	113	#define CEPH_CAPS_PER_RELEASE ((PAGE_SIZE - sizeof(u32) - \
2f2dc053	114	sizeof(struct ceph_mds_cap_release)) / \
92475f05	115	sizeof(struct ceph_mds_cap_item))
2f2dc053 SW	116
	117
	118	/*
	119	* state associated with each MDS<->client session
	120	*/
	121	enum {
	122	CEPH_MDS_SESSION_NEW = 1,
	123	CEPH_MDS_SESSION_OPENING = 2,
	124	CEPH_MDS_SESSION_OPEN = 3,
	125	CEPH_MDS_SESSION_HUNG = 4,
	126	CEPH_MDS_SESSION_CLOSING = 5,
	127	CEPH_MDS_SESSION_RESTARTING = 6,
	128	CEPH_MDS_SESSION_RECONNECTING = 7,
fcff415c	129	CEPH_MDS_SESSION_REJECTED = 8,
2f2dc053 SW	130	};
	131
	132	struct ceph_mds_session {
	133	struct ceph_mds_client *s_mdsc;
	134	int s_mds;
	135	int s_state;
	136	unsigned long s_ttl; /* time until mds kills us */
	137	u64 s_seq; /* incoming msg seq # */
	138	struct mutex s_mutex; /* serialize session messages */
	139
	140	struct ceph_connection s_con;
	141
6c4a1915	142	struct ceph_auth_handshake s_auth;
4e7a5dcd	143
d8fb02ab AE	144	/* protected by s_gen_ttl_lock */
d8fb02ab AE	145	spinlock_t s_gen_ttl_lock;
2f2dc053 SW	146	u32 s_cap_gen; /* inc each time we get mds stale msg */
2f2dc053 SW	147	unsigned long s_cap_ttl; /* when session caps expire */
d8fb02ab AE	148
	149	/* protected by s_cap_lock */
	150	spinlock_t s_cap_lock;
2f2dc053 SW	151	struct list_head s_caps; /* all caps issued by this session */
	152	int s_nr_caps, s_trim_caps;
	153	int s_num_cap_releases;
99a9c273	154	int s_cap_reconnect;
03f4fcb0	155	int s_readonly;
2f2dc053	156	struct list_head s_cap_releases; /* waiting cap_release messages */
7c1332b8	157	struct ceph_cap *s_cap_iterator;
2f2dc053 SW	158
	159	/* protected by mutex */
	160	struct list_head s_cap_flushing; /* inodes w/ flushing caps */
2f2dc053 SW	161	unsigned long s_renew_requested; /* last time we sent a renew req */
	162	u64 s_renew_seq;
	163
3997c01d	164	refcount_t s_ref;
2f2dc053 SW	165	struct list_head s_waiting; /* waiting requests */
	166	struct list_head s_unsafe; /* unsafe requests */
	167	};
	168
	169	/*
	170	* modes of choosing which MDS to send a request to
	171	*/
	172	enum {
	173	USE_ANY_MDS,
	174	USE_RANDOM_MDS,
	175	USE_AUTH_MDS, /* prefer authoritative mds for this metadata item */
	176	};
	177
	178	struct ceph_mds_request;
	179	struct ceph_mds_client;
	180
	181	/*
	182	* request completion callback
	183	*/
	184	typedef void (ceph_mds_request_callback_t) (struct ceph_mds_client mdsc,
	185	struct ceph_mds_request *req);
9280be24 YZ	186	/*
	187	* wait for request completion callback
	188	*/
	189	typedef int (ceph_mds_request_wait_callback_t) (struct ceph_mds_client mdsc,
	190	struct ceph_mds_request *req);
2f2dc053 SW	191
	192	/*
	193	* an in-flight mds request
	194	*/
	195	struct ceph_mds_request {
	196	u64 r_tid; /* transaction id */
44ca18f2	197	struct rb_node r_node;
37151668	198	struct ceph_mds_client *r_mdsc;
2f2dc053 SW	199
2f2dc053 SW	200	int r_op; /* mds op code */
2f2dc053 SW	201
	202	/* operation on what? */
	203	struct inode r_inode; / arg1 */
	204	struct dentry r_dentry; / arg1 */
	205	struct dentry r_old_dentry; / arg2: rename from or link from */
41b02e1f	206	struct inode r_old_dentry_dir; / arg2: old dentry's parent dir */
2f2dc053 SW	207	char r_path1, r_path2;
	208	struct ceph_vino r_ino1, r_ino2;
	209
3dd69aab	210	struct inode r_parent; / parent dir inode */
2f2dc053 SW	211	struct inode r_target_inode; / resulting inode */
2f2dc053 SW	212
bc2de10d JL	213	#define CEPH_MDS_R_DIRECT_IS_HASH (1) /* r_direct_hash is valid */
	214	#define CEPH_MDS_R_ABORTED (2) /* call was aborted */
	215	#define CEPH_MDS_R_GOT_UNSAFE (3) /* got an unsafe reply */
	216	#define CEPH_MDS_R_GOT_SAFE (4) /* got a safe reply */
	217	#define CEPH_MDS_R_GOT_RESULT (5) /* got a result */
	218	#define CEPH_MDS_R_DID_PREPOPULATE (6) /* prepopulated readdir */
3dd69aab	219	#define CEPH_MDS_R_PARENT_LOCKED (7) /* is r_parent->i_rwsem wlocked? */
bc2de10d JL	220	unsigned long r_req_flags;
bc2de10d JL	221
b4556396 SW	222	struct mutex r_fill_mutex;
b4556396 SW	223
2f2dc053 SW	224	union ceph_mds_request_args r_args;
2f2dc053 SW	225	int r_fmode; /* file mode, if expecting cap */
ff3d0046 EB	226	kuid_t r_uid;
ff3d0046 EB	227	kgid_t r_gid;
b8e69066	228	struct timespec r_stamp;
2f2dc053 SW	229
	230	/* for choosing which mds to send this request to */
	231	int r_direct_mode;
	232	u32 r_direct_hash; /* choose dir frag based on this dentry hash */
2f2dc053 SW	233
2f2dc053 SW	234	/* data payload is used for xattr ops */
25e6bae3	235	struct ceph_pagelist *r_pagelist;
2f2dc053 SW	236
	237	/* what caps shall we drop? */
	238	int r_inode_drop, r_inode_unless;
	239	int r_dentry_drop, r_dentry_unless;
	240	int r_old_dentry_drop, r_old_dentry_unless;
	241	struct inode *r_old_inode;
	242	int r_old_inode_drop, r_old_inode_unless;
	243
	244	struct ceph_msg r_request; / original request */
e979cf50	245	int r_request_release_offset;
2f2dc053 SW	246	struct ceph_msg *r_reply;
2f2dc053 SW	247	struct ceph_mds_reply_info_parsed r_reply_info;
01deead0	248	struct page *r_locked_page;
2f2dc053 SW	249	int r_err;
2f2dc053 SW	250
a319bf56	251	unsigned long r_timeout; /* optional. jiffies, 0 is "wait forever" */
2f2dc053 SW	252	unsigned long r_started; /* start time to measure timeout against */
	253	unsigned long r_request_started; /* start time for mds request only,
	254	used to measure lease durations */
	255
	256	/* link unsafe requests to parent directory, for fsync */
	257	struct inode *r_unsafe_dir;
	258	struct list_head r_unsafe_dir_item;
	259
68cd5b4b YZ	260	/* unsafe requests that modify the target inode */
	261	struct list_head r_unsafe_target_item;
	262
2f2dc053 SW	263	struct ceph_mds_session *r_session;
	264
	265	int r_attempts; /* resend attempts */
	266	int r_num_fwd; /* number of forward attempts */
2f2dc053	267	int r_resend_mds; /* mds to resend to next, if any*/
e55b71f8	268	u32 r_sent_on_mseq; /* cap mseq request was sent at*/
2f2dc053	269
153c8e6b	270	struct kref r_kref;
2f2dc053 SW	271	struct list_head r_wait;
	272	struct completion r_completion;
	273	struct completion r_safe_completion;
	274	ceph_mds_request_callback_t r_callback;
9280be24	275	ceph_mds_request_wait_callback_t r_wait_for_completion;
2f2dc053	276	struct list_head r_unsafe_item; /* per-session unsafe list item */
2f2dc053	277
fdd4e158 YZ	278	long long r_dir_release_cnt;
	279	long long r_dir_ordered_cnt;
	280	int r_readdir_cache_idx;
2f2dc053 SW	281	u32 r_readdir_offset;
	282
	283	struct ceph_cap_reservation r_caps_reservation;
	284	int r_num_caps;
	285	};
	286
10183a69 YZ	287	struct ceph_pool_perm {
10183a69 YZ	288	struct rb_node node;
10183a69	289	int perm;
7627151e	290	s64 pool;
779fe0fb YZ	291	size_t pool_ns_len;
779fe0fb YZ	292	char pool_ns[];
10183a69 YZ	293	};
10183a69 YZ	294
2f2dc053 SW	295	/*
	296	* mds client state
	297	*/
	298	struct ceph_mds_client {
3d14c5d2	299	struct ceph_fs_client *fsc;
2f2dc053 SW	300	struct mutex mutex; /* all nested structures */
	301
	302	struct ceph_mdsmap *mdsmap;
f3c60c59 SW	303	struct completion safe_umount_waiters;
f3c60c59 SW	304	wait_queue_head_t session_close_wq;
2f2dc053	305	struct list_head waiting_for_map;
430afbad	306	int mdsmap_err;
2f2dc053 SW	307
2f2dc053 SW	308	struct ceph_mds_session *sessions; / NULL for mds if no session */
86d8f67b	309	atomic_t num_sessions;
2f2dc053 SW	310	int max_sessions; /* len of s_mds_sessions */
	311	int stopping; /* true if shutting down */
	312
	313	/*
	314	* snap_rwsem will cover cap linkage into snaprealms, and
	315	* realm snap contexts. (later, we can do per-realm snap
	316	* contexts locks..) the empty list contains realms with no
	317	* references (implying they contain no inodes with caps) that
	318	* should be destroyed.
	319	*/
affbc19a	320	u64 last_snap_seq;
2f2dc053	321	struct rw_semaphore snap_rwsem;
a105f00c	322	struct rb_root snap_realms;
2f2dc053 SW	323	struct list_head snap_empty;
	324	spinlock_t snap_empty_lock; /* protect snap_empty */
	325
	326	u64 last_tid; /* most recent mds request */
e8a7b8b1 YZ	327	u64 oldest_tid; /* oldest incomplete mds request,
e8a7b8b1 YZ	328	excluding setfilelock requests */
44ca18f2	329	struct rb_root request_tree; /* pending mds requests */
2f2dc053 SW	330	struct delayed_work delayed_work; /* delayed work */
	331	unsigned long last_renew_caps; /* last time we renewed our caps */
	332	struct list_head cap_delay_list; /* caps with delayed release */
	333	spinlock_t cap_delay_lock; /* protects cap_delay_list */
	334	struct list_head snap_flush_list; /* cap_snaps ready to flush */
	335	spinlock_t snap_flush_lock;
	336
553adfd9	337	u64 last_cap_flush_tid;
e4500b5e	338	struct list_head cap_flush_list;
2f2dc053	339	struct list_head cap_dirty; /* inodes with dirty caps */
db354052	340	struct list_head cap_dirty_migrating; /* ...that are migration... */
2f2dc053 SW	341	int num_cap_flushing; /* # caps we are flushing */
	342	spinlock_t cap_dirty_lock; /* protects above items */
	343	wait_queue_head_t cap_flushing_wq;
	344
37151668 YS	345	/*
	346	* Cap reservations
	347	*
	348	* Maintain a global pool of preallocated struct ceph_caps, referenced
	349	* by struct ceph_caps_reservations. This ensures that we preallocate
	350	* memory needed to successfully process an MDS response. (If an MDS
	351	* sends us cap information and we fail to process it, we will have
	352	* problems due to the client and MDS being out of sync.)
	353	*
	354	* Reservations are 'owned' by a ceph_cap_reservation context.
	355	*/
	356	spinlock_t caps_list_lock;
	357	struct list_head caps_list; /* unused (reserved or
	358	unreserved) */
	359	int caps_total_count; /* total caps allocated */
	360	int caps_use_count; /* in use */
	361	int caps_reserve_count; /* unused, reserved */
	362	int caps_avail_count; /* unused, unreserved */
	363	int caps_min_count; /* keep at least this many
	364	(unreserved) */
2f2dc053 SW	365	spinlock_t dentry_lru_lock;
	366	struct list_head dentry_lru;
	367	int num_dentry;
10183a69 YZ	368
	369	struct rw_semaphore pool_perm_rwsem;
	370	struct rb_root pool_perm_tree;
2f2dc053 SW	371	};
	372
	373	extern const char *ceph_mds_op_name(int op);
	374
	375	extern struct ceph_mds_session *
	376	__ceph_lookup_mds_session(struct ceph_mds_client *, int mds);
	377
	378	static inline struct ceph_mds_session *
	379	ceph_get_mds_session(struct ceph_mds_session *s)
	380	{
3997c01d	381	refcount_inc(&s->s_ref);
2f2dc053 SW	382	return s;
	383	}
	384
a687ecaf JS	385	extern const char *ceph_session_state_name(int s);
a687ecaf JS	386
2f2dc053 SW	387	extern void ceph_put_mds_session(struct ceph_mds_session *s);
	388
	389	extern int ceph_send_msg_mds(struct ceph_mds_client *mdsc,
	390	struct ceph_msg *msg, int mds);
	391
3d14c5d2	392	extern int ceph_mdsc_init(struct ceph_fs_client *fsc);
2f2dc053	393	extern void ceph_mdsc_close_sessions(struct ceph_mds_client *mdsc);
48fec5d0	394	extern void ceph_mdsc_force_umount(struct ceph_mds_client *mdsc);
3d14c5d2	395	extern void ceph_mdsc_destroy(struct ceph_fs_client *fsc);
2f2dc053 SW	396
	397	extern void ceph_mdsc_sync(struct ceph_mds_client *mdsc);
	398
167c9e35	399	extern void ceph_invalidate_dir_request(struct ceph_mds_request *req);
54008399 YZ	400	extern int ceph_alloc_readdir_reply_buffer(struct ceph_mds_request *req,
54008399 YZ	401	struct inode *dir);
2f2dc053 SW	402	extern struct ceph_mds_request *
	403	ceph_mdsc_create_request(struct ceph_mds_client *mdsc, int op, int mode);
	404	extern void ceph_mdsc_submit_request(struct ceph_mds_client *mdsc,
	405	struct ceph_mds_request *req);
	406	extern int ceph_mdsc_do_request(struct ceph_mds_client *mdsc,
	407	struct inode *dir,
	408	struct ceph_mds_request *req);
	409	static inline void ceph_mdsc_get_request(struct ceph_mds_request *req)
	410	{
153c8e6b SW	411	kref_get(&req->r_kref);
	412	}
	413	extern void ceph_mdsc_release_request(struct kref *kref);
	414	static inline void ceph_mdsc_put_request(struct ceph_mds_request *req)
	415	{
	416	kref_put(&req->r_kref, ceph_mdsc_release_request);
2f2dc053	417	}
2f2dc053	418
3d7ded4d SW	419	extern void ceph_send_cap_releases(struct ceph_mds_client *mdsc,
	420	struct ceph_mds_session *session);
	421
2f2dc053 SW	422	extern void ceph_mdsc_pre_umount(struct ceph_mds_client *mdsc);
	423
	424	extern char ceph_mdsc_build_path(struct dentry dentry, int plen, u64 base,
	425	int stop_on_nosnap);
	426
	427	extern void __ceph_mdsc_drop_dentry_lease(struct dentry *dentry);
	428	extern void ceph_mdsc_lease_send_msg(struct ceph_mds_session *session,
	429	struct inode *inode,
	430	struct dentry *dentry, char action,
	431	u32 seq);
	432
430afbad YZ	433	extern void ceph_mdsc_handle_mdsmap(struct ceph_mds_client *mdsc,
	434	struct ceph_msg *msg);
	435	extern void ceph_mdsc_handle_fsmap(struct ceph_mds_client *mdsc,
	436	struct ceph_msg *msg);
2f2dc053	437
5d72d13c YZ	438	extern struct ceph_mds_session *
5d72d13c YZ	439	ceph_mdsc_open_export_target_session(struct ceph_mds_client *mdsc, int target);
154f42c2 SW	440	extern void ceph_mdsc_open_export_target_sessions(struct ceph_mds_client *mdsc,
	441	struct ceph_mds_session *session);
	442
2f2dc053	443	#endif