libceph: mon_get_version request infrastructure

Add support for mon_get_version requests to libceph.  This reuses much
of the ceph_mon_generic_request infrastructure, with one exception.
Older OSDs don't set mon_get_version reply hdr->tid even if the
original request had a non-zero tid, which makes it impossible to
lookup ceph_mon_generic_request contexts by tid in get_generic_reply()
for such replies.  As a workaround, we allocate a reply message on the
reply path.  This can probably interfere with revoke, but I don't see
a better way.

Signed-off-by: Ilya Dryomov <ilya.dryomov@inktank.com>
Reviewed-by: Sage Weil <sage@inktank.com>
This commit is contained in:
Ilya Dryomov 2014-05-13 11:19:26 +04:00 committed by Yan, Zheng
parent 002b36ba5e
commit 513a8243d6
4 changed files with 128 additions and 8 deletions

View file

@ -40,9 +40,9 @@ struct ceph_mon_request {
};
/*
* ceph_mon_generic_request is being used for the statfs and poolop requests
* which are bening done a bit differently because we need to get data back
* to the caller
* ceph_mon_generic_request is being used for the statfs, poolop and
* mon_get_version requests which are being done a bit differently
* because we need to get data back to the caller
*/
struct ceph_mon_generic_request {
struct kref kref;
@ -108,6 +108,9 @@ extern void ceph_monc_request_next_osdmap(struct ceph_mon_client *monc);
extern int ceph_monc_do_statfs(struct ceph_mon_client *monc,
struct ceph_statfs *buf);
extern int ceph_monc_do_get_version(struct ceph_mon_client *monc,
const char *what, u64 *newest);
extern int ceph_monc_open_session(struct ceph_mon_client *monc);
extern int ceph_monc_validate_auth(struct ceph_mon_client *monc);

View file

@ -72,6 +72,8 @@ const char *ceph_msg_type_name(int type)
case CEPH_MSG_MON_SUBSCRIBE_ACK: return "mon_subscribe_ack";
case CEPH_MSG_STATFS: return "statfs";
case CEPH_MSG_STATFS_REPLY: return "statfs_reply";
case CEPH_MSG_MON_GET_VERSION: return "mon_get_version";
case CEPH_MSG_MON_GET_VERSION_REPLY: return "mon_get_version_reply";
case CEPH_MSG_MDS_MAP: return "mds_map";
case CEPH_MSG_CLIENT_SESSION: return "client_session";
case CEPH_MSG_CLIENT_RECONNECT: return "client_reconnect";

View file

@ -129,6 +129,8 @@ static int monc_show(struct seq_file *s, void *p)
seq_printf(s, "%llu statfs\n", req->tid);
else if (op == CEPH_MSG_POOLOP)
seq_printf(s, "%llu poolop\n", req->tid);
else if (op == CEPH_MSG_MON_GET_VERSION)
seq_printf(s, "%llu mon_get_version", req->tid);
else
seq_printf(s, "%llu unknown\n", req->tid);
}

View file

@ -477,14 +477,13 @@ static struct ceph_msg *get_generic_reply(struct ceph_connection *con,
return m;
}
static int do_generic_request(struct ceph_mon_client *monc,
struct ceph_mon_generic_request *req)
static int __do_generic_request(struct ceph_mon_client *monc, u64 tid,
struct ceph_mon_generic_request *req)
{
int err;
/* register request */
mutex_lock(&monc->mutex);
req->tid = ++monc->last_tid;
req->tid = tid != 0 ? tid : ++monc->last_tid;
req->request->hdr.tid = cpu_to_le64(req->tid);
__insert_generic_request(monc, req);
monc->num_generic_requests++;
@ -496,13 +495,24 @@ static int do_generic_request(struct ceph_mon_client *monc,
mutex_lock(&monc->mutex);
rb_erase(&req->node, &monc->generic_request_tree);
monc->num_generic_requests--;
mutex_unlock(&monc->mutex);
if (!err)
err = req->result;
return err;
}
static int do_generic_request(struct ceph_mon_client *monc,
struct ceph_mon_generic_request *req)
{
int err;
mutex_lock(&monc->mutex);
err = __do_generic_request(monc, 0, req);
mutex_unlock(&monc->mutex);
return err;
}
/*
* statfs
*/
@ -579,6 +589,96 @@ int ceph_monc_do_statfs(struct ceph_mon_client *monc, struct ceph_statfs *buf)
}
EXPORT_SYMBOL(ceph_monc_do_statfs);
static void handle_get_version_reply(struct ceph_mon_client *monc,
struct ceph_msg *msg)
{
struct ceph_mon_generic_request *req;
u64 tid = le64_to_cpu(msg->hdr.tid);
void *p = msg->front.iov_base;
void *end = p + msg->front_alloc_len;
u64 handle;
dout("%s %p tid %llu\n", __func__, msg, tid);
ceph_decode_need(&p, end, 2*sizeof(u64), bad);
handle = ceph_decode_64(&p);
if (tid != 0 && tid != handle)
goto bad;
mutex_lock(&monc->mutex);
req = __lookup_generic_req(monc, handle);
if (req) {
*(u64 *)req->buf = ceph_decode_64(&p);
req->result = 0;
get_generic_request(req);
}
mutex_unlock(&monc->mutex);
if (req) {
complete_all(&req->completion);
put_generic_request(req);
}
return;
bad:
pr_err("corrupt mon_get_version reply\n");
ceph_msg_dump(msg);
}
/*
* Send MMonGetVersion and wait for the reply.
*
* @what: one of "mdsmap", "osdmap" or "monmap"
*/
int ceph_monc_do_get_version(struct ceph_mon_client *monc, const char *what,
u64 *newest)
{
struct ceph_mon_generic_request *req;
void *p, *end;
u64 tid;
int err;
req = kzalloc(sizeof(*req), GFP_NOFS);
if (!req)
return -ENOMEM;
kref_init(&req->kref);
req->buf = newest;
req->buf_len = sizeof(*newest);
init_completion(&req->completion);
req->request = ceph_msg_new(CEPH_MSG_MON_GET_VERSION,
sizeof(u64) + sizeof(u32) + strlen(what),
GFP_NOFS, true);
if (!req->request) {
err = -ENOMEM;
goto out;
}
req->reply = ceph_msg_new(CEPH_MSG_MON_GET_VERSION_REPLY, 1024,
GFP_NOFS, true);
if (!req->reply) {
err = -ENOMEM;
goto out;
}
p = req->request->front.iov_base;
end = p + req->request->front_alloc_len;
/* fill out request */
mutex_lock(&monc->mutex);
tid = ++monc->last_tid;
ceph_encode_64(&p, tid); /* handle */
ceph_encode_string(&p, end, what, strlen(what));
err = __do_generic_request(monc, tid, req);
mutex_unlock(&monc->mutex);
out:
kref_put(&req->kref, release_generic_request);
return err;
}
EXPORT_SYMBOL(ceph_monc_do_get_version);
/*
* pool ops
*/
@ -981,6 +1081,10 @@ static void dispatch(struct ceph_connection *con, struct ceph_msg *msg)
handle_statfs_reply(monc, msg);
break;
case CEPH_MSG_MON_GET_VERSION_REPLY:
handle_get_version_reply(monc, msg);
break;
case CEPH_MSG_POOLOP_REPLY:
handle_poolop_reply(monc, msg);
break;
@ -1029,6 +1133,15 @@ static struct ceph_msg *mon_alloc_msg(struct ceph_connection *con,
case CEPH_MSG_AUTH_REPLY:
m = ceph_msg_get(monc->m_auth_reply);
break;
case CEPH_MSG_MON_GET_VERSION_REPLY:
if (le64_to_cpu(hdr->tid) != 0)
return get_generic_reply(con, hdr, skip);
/*
* Older OSDs don't set reply tid even if the orignal
* request had a non-zero tid. Workaround this weirdness
* by falling through to the allocate case.
*/
case CEPH_MSG_MON_MAP:
case CEPH_MSG_MDS_MAP:
case CEPH_MSG_OSD_MAP: