ceph: factor out libceph from Ceph file system
This factors out protocol and low-level storage parts of ceph into a
separate libceph module living in net/ceph and include/linux/ceph. This
is mostly a matter of moving files around. However, a few key pieces
of the interface change as well:
- ceph_client becomes ceph_fs_client and ceph_client, where the latter
captures the mon and osd clients, and the fs_client gets the mds client
and file system specific pieces.
- Mount option parsing and debugfs setup is correspondingly broken into
two pieces.
- The mon client gets a generic handler callback for otherwise unknown
messages (mds map, in this case).
- The basic supported/required feature bits can be expanded (and are by
ceph_fs_client).
No functional change, aside from some subtle error handling cases that got
cleaned up in the refactoring process.
Signed-off-by: Sage Weil <sage@newdream.net>
diff --git a/include/linux/ceph/messenger.h b/include/linux/ceph/messenger.h
new file mode 100644
index 0000000..5956d62
--- /dev/null
+++ b/include/linux/ceph/messenger.h
@@ -0,0 +1,261 @@
+#ifndef __FS_CEPH_MESSENGER_H
+#define __FS_CEPH_MESSENGER_H
+
+#include <linux/kref.h>
+#include <linux/mutex.h>
+#include <linux/net.h>
+#include <linux/radix-tree.h>
+#include <linux/uio.h>
+#include <linux/version.h>
+#include <linux/workqueue.h>
+
+#include "types.h"
+#include "buffer.h"
+
+struct ceph_msg;
+struct ceph_connection;
+
+extern struct workqueue_struct *ceph_msgr_wq; /* receive work queue */
+
+/*
+ * Ceph defines these callbacks for handling connection events.
+ */
+struct ceph_connection_operations {
+ struct ceph_connection *(*get)(struct ceph_connection *);
+ void (*put)(struct ceph_connection *);
+
+ /* handle an incoming message. */
+ void (*dispatch) (struct ceph_connection *con, struct ceph_msg *m);
+
+ /* authorize an outgoing connection */
+ int (*get_authorizer) (struct ceph_connection *con,
+ void **buf, int *len, int *proto,
+ void **reply_buf, int *reply_len, int force_new);
+ int (*verify_authorizer_reply) (struct ceph_connection *con, int len);
+ int (*invalidate_authorizer)(struct ceph_connection *con);
+
+ /* protocol version mismatch */
+ void (*bad_proto) (struct ceph_connection *con);
+
+ /* there was some error on the socket (disconnect, whatever) */
+ void (*fault) (struct ceph_connection *con);
+
+ /* a remote host as terminated a message exchange session, and messages
+ * we sent (or they tried to send us) may be lost. */
+ void (*peer_reset) (struct ceph_connection *con);
+
+ struct ceph_msg * (*alloc_msg) (struct ceph_connection *con,
+ struct ceph_msg_header *hdr,
+ int *skip);
+};
+
+/* use format string %s%d */
+#define ENTITY_NAME(n) ceph_entity_type_name((n).type), le64_to_cpu((n).num)
+
+struct ceph_messenger {
+ struct ceph_entity_inst inst; /* my name+address */
+ struct ceph_entity_addr my_enc_addr;
+ struct page *zero_page; /* used in certain error cases */
+
+ bool nocrc;
+
+ /*
+ * the global_seq counts connections i (attempt to) initiate
+ * in order to disambiguate certain connect race conditions.
+ */
+ u32 global_seq;
+ spinlock_t global_seq_lock;
+
+ u32 supported_features;
+ u32 required_features;
+};
+
+/*
+ * a single message. it contains a header (src, dest, message type, etc.),
+ * footer (crc values, mainly), a "front" message body, and possibly a
+ * data payload (stored in some number of pages).
+ */
+struct ceph_msg {
+ struct ceph_msg_header hdr; /* header */
+ struct ceph_msg_footer footer; /* footer */
+ struct kvec front; /* unaligned blobs of message */
+ struct ceph_buffer *middle;
+ struct page **pages; /* data payload. NOT OWNER. */
+ unsigned nr_pages; /* size of page array */
+ struct ceph_pagelist *pagelist; /* instead of pages */
+ struct list_head list_head;
+ struct kref kref;
+ struct bio *bio; /* instead of pages/pagelist */
+ struct bio *bio_iter; /* bio iterator */
+ int bio_seg; /* current bio segment */
+ struct ceph_pagelist *trail; /* the trailing part of the data */
+ bool front_is_vmalloc;
+ bool more_to_follow;
+ bool needs_out_seq;
+ int front_max;
+
+ struct ceph_msgpool *pool;
+};
+
+struct ceph_msg_pos {
+ int page, page_pos; /* which page; offset in page */
+ int data_pos; /* offset in data payload */
+ int did_page_crc; /* true if we've calculated crc for current page */
+};
+
+/* ceph connection fault delay defaults, for exponential backoff */
+#define BASE_DELAY_INTERVAL (HZ/2)
+#define MAX_DELAY_INTERVAL (5 * 60 * HZ)
+
+/*
+ * ceph_connection state bit flags
+ *
+ * QUEUED and BUSY are used together to ensure that only a single
+ * thread is currently opening, reading or writing data to the socket.
+ */
+#define LOSSYTX 0 /* we can close channel or drop messages on errors */
+#define CONNECTING 1
+#define NEGOTIATING 2
+#define KEEPALIVE_PENDING 3
+#define WRITE_PENDING 4 /* we have data ready to send */
+#define QUEUED 5 /* there is work queued on this connection */
+#define BUSY 6 /* work is being done */
+#define STANDBY 8 /* no outgoing messages, socket closed. we keep
+ * the ceph_connection around to maintain shared
+ * state with the peer. */
+#define CLOSED 10 /* we've closed the connection */
+#define SOCK_CLOSED 11 /* socket state changed to closed */
+#define OPENING 13 /* open connection w/ (possibly new) peer */
+#define DEAD 14 /* dead, about to kfree */
+
+/*
+ * A single connection with another host.
+ *
+ * We maintain a queue of outgoing messages, and some session state to
+ * ensure that we can preserve the lossless, ordered delivery of
+ * messages in the case of a TCP disconnect.
+ */
+struct ceph_connection {
+ void *private;
+ atomic_t nref;
+
+ const struct ceph_connection_operations *ops;
+
+ struct ceph_messenger *msgr;
+ struct socket *sock;
+ unsigned long state; /* connection state (see flags above) */
+ const char *error_msg; /* error message, if any */
+
+ struct ceph_entity_addr peer_addr; /* peer address */
+ struct ceph_entity_name peer_name; /* peer name */
+ struct ceph_entity_addr peer_addr_for_me;
+ unsigned peer_features;
+ u32 connect_seq; /* identify the most recent connection
+ attempt for this connection, client */
+ u32 peer_global_seq; /* peer's global seq for this connection */
+
+ int auth_retry; /* true if we need a newer authorizer */
+ void *auth_reply_buf; /* where to put the authorizer reply */
+ int auth_reply_buf_len;
+
+ struct mutex mutex;
+
+ /* out queue */
+ struct list_head out_queue;
+ struct list_head out_sent; /* sending or sent but unacked */
+ u64 out_seq; /* last message queued for send */
+ bool out_keepalive_pending;
+
+ u64 in_seq, in_seq_acked; /* last message received, acked */
+
+ /* connection negotiation temps */
+ char in_banner[CEPH_BANNER_MAX_LEN];
+ union {
+ struct { /* outgoing connection */
+ struct ceph_msg_connect out_connect;
+ struct ceph_msg_connect_reply in_reply;
+ };
+ struct { /* incoming */
+ struct ceph_msg_connect in_connect;
+ struct ceph_msg_connect_reply out_reply;
+ };
+ };
+ struct ceph_entity_addr actual_peer_addr;
+
+ /* message out temps */
+ struct ceph_msg *out_msg; /* sending message (== tail of
+ out_sent) */
+ bool out_msg_done;
+ struct ceph_msg_pos out_msg_pos;
+
+ struct kvec out_kvec[8], /* sending header/footer data */
+ *out_kvec_cur;
+ int out_kvec_left; /* kvec's left in out_kvec */
+ int out_skip; /* skip this many bytes */
+ int out_kvec_bytes; /* total bytes left */
+ bool out_kvec_is_msg; /* kvec refers to out_msg */
+ int out_more; /* there is more data after the kvecs */
+ __le64 out_temp_ack; /* for writing an ack */
+
+ /* message in temps */
+ struct ceph_msg_header in_hdr;
+ struct ceph_msg *in_msg;
+ struct ceph_msg_pos in_msg_pos;
+ u32 in_front_crc, in_middle_crc, in_data_crc; /* calculated crc */
+
+ char in_tag; /* protocol control byte */
+ int in_base_pos; /* bytes read */
+ __le64 in_temp_ack; /* for reading an ack */
+
+ struct delayed_work work; /* send|recv work */
+ unsigned long delay; /* current delay interval */
+};
+
+
+extern const char *ceph_pr_addr(const struct sockaddr_storage *ss);
+extern int ceph_parse_ips(const char *c, const char *end,
+ struct ceph_entity_addr *addr,
+ int max_count, int *count);
+
+
+extern int ceph_msgr_init(void);
+extern void ceph_msgr_exit(void);
+extern void ceph_msgr_flush(void);
+
+extern struct ceph_messenger *ceph_messenger_create(
+ struct ceph_entity_addr *myaddr,
+ u32 features, u32 required);
+extern void ceph_messenger_destroy(struct ceph_messenger *);
+
+extern void ceph_con_init(struct ceph_messenger *msgr,
+ struct ceph_connection *con);
+extern void ceph_con_open(struct ceph_connection *con,
+ struct ceph_entity_addr *addr);
+extern bool ceph_con_opened(struct ceph_connection *con);
+extern void ceph_con_close(struct ceph_connection *con);
+extern void ceph_con_send(struct ceph_connection *con, struct ceph_msg *msg);
+extern void ceph_con_revoke(struct ceph_connection *con, struct ceph_msg *msg);
+extern void ceph_con_revoke_message(struct ceph_connection *con,
+ struct ceph_msg *msg);
+extern void ceph_con_keepalive(struct ceph_connection *con);
+extern struct ceph_connection *ceph_con_get(struct ceph_connection *con);
+extern void ceph_con_put(struct ceph_connection *con);
+
+extern struct ceph_msg *ceph_msg_new(int type, int front_len, gfp_t flags);
+extern void ceph_msg_kfree(struct ceph_msg *m);
+
+
+static inline struct ceph_msg *ceph_msg_get(struct ceph_msg *msg)
+{
+ kref_get(&msg->kref);
+ return msg;
+}
+extern void ceph_msg_last_put(struct kref *kref);
+static inline void ceph_msg_put(struct ceph_msg *msg)
+{
+ kref_put(&msg->kref, ceph_msg_last_put);
+}
+
+extern void ceph_msg_dump(struct ceph_msg *msg);
+
+#endif