#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> #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; }; /* * 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; 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; }; /* 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. */ #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_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; 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 */ /* 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_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 */ kuid_t r_uid; kgid_t r_gid; /* 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 */ 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; }; 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); 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