libceph: async MON client generic requests

For map check, we are going to need to send CEPH_MSG_MON_GET_VERSION
messages asynchronously and get a callback on completion.  Refactor MON
client to allow firing off generic requests asynchronously and add an
async variant of ceph_monc_get_version().  ceph_monc_do_statfs() is
switched over and remains sync.

Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
This commit is contained in:
Ilya Dryomov 2016-04-28 16:07:27 +02:00
parent b07d3c4bd7
commit d0b19705e9
3 changed files with 232 additions and 115 deletions

View File

@ -4896,8 +4896,8 @@ static int rbd_add_get_pool_id(struct rbd_client *rbdc, const char *pool_name)
again:
ret = ceph_pg_poolid_by_name(rbdc->client->osdc.osdmap, pool_name);
if (ret == -ENOENT && tries++ < 1) {
ret = ceph_monc_do_get_version(&rbdc->client->monc, "osdmap",
&newest_epoch);
ret = ceph_monc_get_version(&rbdc->client->monc, "osdmap",
&newest_epoch);
if (ret < 0)
return ret;

View File

@ -39,20 +39,31 @@ struct ceph_mon_request {
ceph_monc_request_func_t do_request;
};
typedef void (*ceph_monc_callback_t)(struct ceph_mon_generic_request *);
/*
* ceph_mon_generic_request is being used for the statfs 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 ceph_mon_client *monc;
struct kref kref;
u64 tid;
struct rb_node node;
int result;
void *buf;
struct completion completion;
ceph_monc_callback_t complete_cb;
u64 private_data; /* r_tid/linger_id */
struct ceph_msg *request; /* original request */
struct ceph_msg *reply; /* and reply */
union {
struct ceph_statfs *st;
u64 newest;
} u;
};
struct ceph_mon_client {
@ -124,8 +135,10 @@ extern int ceph_monc_wait_osdmap(struct ceph_mon_client *monc, u32 epoch,
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);
int ceph_monc_get_version(struct ceph_mon_client *monc, const char *what,
u64 *newest);
int ceph_monc_get_version_async(struct ceph_mon_client *monc, const char *what,
ceph_monc_callback_t cb, u64 private_data);
extern int ceph_monc_open_session(struct ceph_mon_client *monc);

View File

@ -493,6 +493,10 @@ static void release_generic_request(struct kref *kref)
struct ceph_mon_generic_request *req =
container_of(kref, struct ceph_mon_generic_request, kref);
dout("%s greq %p request %p reply %p\n", __func__, req, req->request,
req->reply);
WARN_ON(!RB_EMPTY_NODE(&req->node));
if (req->reply)
ceph_msg_put(req->reply);
if (req->request)
@ -503,7 +507,8 @@ static void release_generic_request(struct kref *kref)
static void put_generic_request(struct ceph_mon_generic_request *req)
{
kref_put(&req->kref, release_generic_request);
if (req)
kref_put(&req->kref, release_generic_request);
}
static void get_generic_request(struct ceph_mon_generic_request *req)
@ -511,6 +516,103 @@ static void get_generic_request(struct ceph_mon_generic_request *req)
kref_get(&req->kref);
}
static struct ceph_mon_generic_request *
alloc_generic_request(struct ceph_mon_client *monc, gfp_t gfp)
{
struct ceph_mon_generic_request *req;
req = kzalloc(sizeof(*req), gfp);
if (!req)
return NULL;
req->monc = monc;
kref_init(&req->kref);
RB_CLEAR_NODE(&req->node);
init_completion(&req->completion);
dout("%s greq %p\n", __func__, req);
return req;
}
static void register_generic_request(struct ceph_mon_generic_request *req)
{
struct ceph_mon_client *monc = req->monc;
WARN_ON(req->tid);
get_generic_request(req);
req->tid = ++monc->last_tid;
insert_generic_request(&monc->generic_request_tree, req);
}
static void send_generic_request(struct ceph_mon_client *monc,
struct ceph_mon_generic_request *req)
{
WARN_ON(!req->tid);
dout("%s greq %p tid %llu\n", __func__, req, req->tid);
req->request->hdr.tid = cpu_to_le64(req->tid);
ceph_con_send(&monc->con, ceph_msg_get(req->request));
}
static void __finish_generic_request(struct ceph_mon_generic_request *req)
{
struct ceph_mon_client *monc = req->monc;
dout("%s greq %p tid %llu\n", __func__, req, req->tid);
erase_generic_request(&monc->generic_request_tree, req);
ceph_msg_revoke(req->request);
ceph_msg_revoke_incoming(req->reply);
}
static void finish_generic_request(struct ceph_mon_generic_request *req)
{
__finish_generic_request(req);
put_generic_request(req);
}
static void complete_generic_request(struct ceph_mon_generic_request *req)
{
if (req->complete_cb)
req->complete_cb(req);
else
complete_all(&req->completion);
put_generic_request(req);
}
void cancel_generic_request(struct ceph_mon_generic_request *req)
{
struct ceph_mon_client *monc = req->monc;
struct ceph_mon_generic_request *lookup_req;
dout("%s greq %p tid %llu\n", __func__, req, req->tid);
mutex_lock(&monc->mutex);
lookup_req = lookup_generic_request(&monc->generic_request_tree,
req->tid);
if (lookup_req) {
WARN_ON(lookup_req != req);
finish_generic_request(req);
}
mutex_unlock(&monc->mutex);
}
static int wait_generic_request(struct ceph_mon_generic_request *req)
{
int ret;
dout("%s greq %p tid %llu\n", __func__, req, req->tid);
ret = wait_for_completion_interruptible(&req->completion);
if (ret)
cancel_generic_request(req);
else
ret = req->result; /* completed */
return ret;
}
static struct ceph_msg *get_generic_reply(struct ceph_connection *con,
struct ceph_msg_header *hdr,
int *skip)
@ -540,40 +642,6 @@ static struct ceph_msg *get_generic_reply(struct ceph_connection *con,
return m;
}
static int __do_generic_request(struct ceph_mon_client *monc, u64 tid,
struct ceph_mon_generic_request *req)
{
int err;
/* register request */
req->tid = tid != 0 ? tid : ++monc->last_tid;
req->request->hdr.tid = cpu_to_le64(req->tid);
insert_generic_request(&monc->generic_request_tree, req);
ceph_con_send(&monc->con, ceph_msg_get(req->request));
mutex_unlock(&monc->mutex);
err = wait_for_completion_interruptible(&req->completion);
mutex_lock(&monc->mutex);
erase_generic_request(&monc->generic_request_tree, req);
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
*/
@ -584,22 +652,24 @@ static void handle_statfs_reply(struct ceph_mon_client *monc,
struct ceph_mon_statfs_reply *reply = msg->front.iov_base;
u64 tid = le64_to_cpu(msg->hdr.tid);
dout("%s msg %p tid %llu\n", __func__, msg, tid);
if (msg->front.iov_len != sizeof(*reply))
goto bad;
dout("handle_statfs_reply %p tid %llu\n", msg, tid);
mutex_lock(&monc->mutex);
req = lookup_generic_request(&monc->generic_request_tree, tid);
if (req) {
*(struct ceph_statfs *)req->buf = reply->st;
req->result = 0;
get_generic_request(req);
if (!req) {
mutex_unlock(&monc->mutex);
return;
}
req->result = 0;
*req->u.st = reply->st; /* struct */
__finish_generic_request(req);
mutex_unlock(&monc->mutex);
if (req) {
complete_all(&req->completion);
put_generic_request(req);
}
complete_generic_request(req);
return;
bad:
@ -614,39 +684,38 @@ int ceph_monc_do_statfs(struct ceph_mon_client *monc, struct ceph_statfs *buf)
{
struct ceph_mon_generic_request *req;
struct ceph_mon_statfs *h;
int err;
int ret = -ENOMEM;
req = kzalloc(sizeof(*req), GFP_NOFS);
req = alloc_generic_request(monc, GFP_NOFS);
if (!req)
return -ENOMEM;
goto out;
kref_init(&req->kref);
RB_CLEAR_NODE(&req->node);
req->buf = buf;
init_completion(&req->completion);
err = -ENOMEM;
req->request = ceph_msg_new(CEPH_MSG_STATFS, sizeof(*h), GFP_NOFS,
true);
if (!req->request)
goto out;
req->reply = ceph_msg_new(CEPH_MSG_STATFS_REPLY, 1024, GFP_NOFS,
true);
req->reply = ceph_msg_new(CEPH_MSG_STATFS_REPLY, 64, GFP_NOFS, true);
if (!req->reply)
goto out;
req->u.st = buf;
mutex_lock(&monc->mutex);
register_generic_request(req);
/* fill out request */
h = req->request->front.iov_base;
h->monhdr.have_version = 0;
h->monhdr.session_mon = cpu_to_le16(-1);
h->monhdr.session_mon_tid = 0;
h->fsid = monc->monmap->fsid;
send_generic_request(monc, req);
mutex_unlock(&monc->mutex);
err = do_generic_request(monc, req);
ret = wait_generic_request(req);
out:
put_generic_request(req);
return err;
return ret;
}
EXPORT_SYMBOL(ceph_monc_do_statfs);
@ -659,7 +728,7 @@ static void handle_get_version_reply(struct ceph_mon_client *monc,
void *end = p + msg->front_alloc_len;
u64 handle;
dout("%s %p tid %llu\n", __func__, msg, tid);
dout("%s msg %p tid %llu\n", __func__, msg, tid);
ceph_decode_need(&p, end, 2*sizeof(u64), bad);
handle = ceph_decode_64(&p);
@ -668,77 +737,110 @@ static void handle_get_version_reply(struct ceph_mon_client *monc,
mutex_lock(&monc->mutex);
req = lookup_generic_request(&monc->generic_request_tree, 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);
if (!req) {
mutex_unlock(&monc->mutex);
return;
}
req->result = 0;
req->u.newest = ceph_decode_64(&p);
__finish_generic_request(req);
mutex_unlock(&monc->mutex);
complete_generic_request(req);
return;
bad:
pr_err("corrupt mon_get_version reply, tid %llu\n", tid);
ceph_msg_dump(msg);
}
static struct ceph_mon_generic_request *
__ceph_monc_get_version(struct ceph_mon_client *monc, const char *what,
ceph_monc_callback_t cb, u64 private_data)
{
struct ceph_mon_generic_request *req;
req = alloc_generic_request(monc, GFP_NOIO);
if (!req)
goto err_put_req;
req->request = ceph_msg_new(CEPH_MSG_MON_GET_VERSION,
sizeof(u64) + sizeof(u32) + strlen(what),
GFP_NOIO, true);
if (!req->request)
goto err_put_req;
req->reply = ceph_msg_new(CEPH_MSG_MON_GET_VERSION_REPLY, 32, GFP_NOIO,
true);
if (!req->reply)
goto err_put_req;
req->complete_cb = cb;
req->private_data = private_data;
mutex_lock(&monc->mutex);
register_generic_request(req);
{
void *p = req->request->front.iov_base;
void *const end = p + req->request->front_alloc_len;
ceph_encode_64(&p, req->tid); /* handle */
ceph_encode_string(&p, end, what, strlen(what));
WARN_ON(p != end);
}
send_generic_request(monc, req);
mutex_unlock(&monc->mutex);
return req;
err_put_req:
put_generic_request(req);
return ERR_PTR(-ENOMEM);
}
/*
* 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)
int ceph_monc_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;
int ret;
req = kzalloc(sizeof(*req), GFP_NOFS);
if (!req)
return -ENOMEM;
req = __ceph_monc_get_version(monc, what, NULL, 0);
if (IS_ERR(req))
return PTR_ERR(req);
kref_init(&req->kref);
RB_CLEAR_NODE(&req->node);
req->buf = newest;
init_completion(&req->completion);
ret = wait_generic_request(req);
if (!ret)
*newest = req->u.newest;
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:
put_generic_request(req);
return err;
return ret;
}
EXPORT_SYMBOL(ceph_monc_do_get_version);
EXPORT_SYMBOL(ceph_monc_get_version);
/*
* Send MMonGetVersion,
*
* @what: one of "mdsmap", "osdmap" or "monmap"
*/
int ceph_monc_get_version_async(struct ceph_mon_client *monc, const char *what,
ceph_monc_callback_t cb, u64 private_data)
{
struct ceph_mon_generic_request *req;
req = __ceph_monc_get_version(monc, what, cb, private_data);
if (IS_ERR(req))
return PTR_ERR(req);
put_generic_request(req);
return 0;
}
EXPORT_SYMBOL(ceph_monc_get_version_async);
/*
* Resend pending generic requests.
@ -923,6 +1025,8 @@ void ceph_monc_stop(struct ceph_mon_client *monc)
ceph_auth_destroy(monc->auth);
WARN_ON(!RB_EMPTY_ROOT(&monc->generic_request_tree));
ceph_msg_put(monc->m_auth);
ceph_msg_put(monc->m_auth_reply);
ceph_msg_put(monc->m_subscribe);