--- /dev/null
+#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;
+ u64 inline_version;
+ u32 inline_len;
+ char *inline_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;
+ size_t dir_buf_size;
+ 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;
+ int s_cap_reconnect;
+ int s_readonly;
+ 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);
+/*
+ * 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_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;
+ 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 */
+ bool r_direct_is_hash; /* true if r_direct_hash is valid */
+
+ /* 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;
+ 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;
+ ceph_mds_request_wait_callback_t r_wait_for_completion;
+ 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 */
+ 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.
+ */
+ 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 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_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 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 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 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
Code Review / kvmfornfv.git / blobdiff