[PATCH 4/4] nfsd: introduce nfsd4_callback_ops

Christoph Hellwig
2014-09-24T10:17:01Z

Add a higher level abstraction than the rpc_ops for callback operations.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
fs/nfsd/nfs4callback.c | 91 ++++++++++++++++----------------------------------
fs/nfsd/nfs4state.c | 51 +++++++++++++++++++++++++---
fs/nfsd/state.h | 12 ++++---
3 files changed, 83 insertions(+), 71 deletions(-)

diff --git a/fs/nfsd/nfs4callback.c b/fs/nfsd/nfs4callback.c
index 6d9d947..9cc51b9 100644
--- a/fs/nfsd/nfs4callback.c
+++ b/fs/nfsd/nfs4callback.c
@@ -824,18 +824,8 @@ static void nfsd4_cb_done(struct rpc_task *task, void *calldata)
dprintk("%s: freed slot, new seqid=%d\n", __func__,
clp->cl_cb_session->se_cb_seq_nr);
}
-}

-static void nfsd4_cb_recall_done(struct rpc_task *task, void *calldata)
-{
- struct nfsd4_callback *cb = calldata;
- struct nfs4_delegation *dp = to_delegation(cb);
- struct nfs4_client *clp = cb->cb_clp;
- struct rpc_clnt *current_rpc_client = clp->cl_cb_client;
-
- nfsd4_cb_done(task, calldata);
-
- if (current_rpc_client != task->tk_client) {
+ if (clp->cl_cb_client != task->tk_client) {
/* We're shutting down or changing cl_cb_client; leave
* it to nfsd4_process_cb_update to restart the call if
* necessary. */
@@ -844,45 +834,42 @@ static void nfsd4_cb_recall_done(struct rpc_task *task, void *calldata)

if (cb->cb_done)
return;
- switch (task->tk_status) {
+
+ switch (cb->cb_ops->done(cb, task)) {
case 0:
+ task->tk_status = 0;
+ rpc_restart_call_prepare(task);
+ return;
+ case 1:
break;
- case -EBADHANDLE:
- case -NFS4ERR_BAD_STATEID:
- /* Race: client probably got cb_recall
- * before open reply granting delegation */
- if (dp->dl_retries--) {
- rpc_delay(task, 2*HZ);
- task->tk_status = 0;
- rpc_restart_call_prepare(task);
- return;
- }
- default:
+ case -1:
/* Network partition? */
nfsd4_mark_cb_down(clp, task->tk_status);
+ break;
+ default:
+ BUG();
}
cb->cb_done = true;
}

-static void nfsd4_cb_recall_release(void *calldata)
+static void nfsd4_cb_release(void *calldata)
{
struct nfsd4_callback *cb = calldata;
struct nfs4_client *clp = cb->cb_clp;

if (cb->cb_done) {
- struct nfs4_delegation *dp = to_delegation(cb);
-
spin_lock(&clp->cl_lock);
list_del(&cb->cb_per_client);
spin_unlock(&clp->cl_lock);
- nfs4_put_stid(&dp->dl_stid);
+
+ cb->cb_ops->release(cb);
}
}

-static const struct rpc_call_ops nfsd4_cb_recall_ops = {
+static const struct rpc_call_ops nfsd4_cb_ops = {
.rpc_call_prepare = nfsd4_cb_prepare,
- .rpc_call_done = nfsd4_cb_recall_done,
- .rpc_release = nfsd4_cb_recall_release,
+ .rpc_call_done = nfsd4_cb_done,
+ .rpc_release = nfsd4_cb_release,
};

int nfsd4_create_callback_queue(void)
@@ -911,12 +898,6 @@ void nfsd4_shutdown_callback(struct nfs4_client *clp)
flush_workqueue(callback_wq);
}

-static void nfsd4_release_cb(struct nfsd4_callback *cb)
-{
- if (cb->cb_ops->rpc_release)
- cb->cb_ops->rpc_release(cb);
-}
-
/* requires cl_lock: */
static struct nfsd4_conn * __nfsd4_find_backchannel(struct nfs4_client *clp)
{
@@ -983,54 +964,40 @@ static void nfsd4_process_cb_update(struct nfsd4_callback *cb)
}

static void
-nfsd4_run_callback_rpc(struct nfsd4_callback *cb)
+nfsd4_run_cb_work(struct work_struct *work)
{
+ struct nfsd4_callback *cb =
+ container_of(work, struct nfsd4_callback, cb_work);
struct nfs4_client *clp = cb->cb_clp;
struct rpc_clnt *clnt;

+ if (cb->cb_ops && cb->cb_ops->prepare)
+ cb->cb_ops->prepare(cb);
+
if (clp->cl_flags & NFSD4_CLIENT_CB_FLAG_MASK)
nfsd4_process_cb_update(cb);

clnt = clp->cl_cb_client;
if (!clnt) {
/* Callback channel broken, or client killed; give up: */
- nfsd4_release_cb(cb);
+ if (cb->cb_ops && cb->cb_ops->release)
+ cb->cb_ops->release(cb);
return;
}
cb->cb_msg.rpc_cred = clp->cl_cb_cred;
rpc_call_async(clnt, &cb->cb_msg, RPC_TASK_SOFT | RPC_TASK_SOFTCONN,
- cb->cb_ops, cb);
-}
-
-void
-nfsd4_run_cb_null(struct work_struct *w)
-{
- struct nfsd4_callback *cb = container_of(w, struct nfsd4_callback,
- cb_work);
- nfsd4_run_callback_rpc(cb);
-}
-
-void
-nfsd4_run_cb_recall(struct work_struct *w)
-{
- struct nfsd4_callback *cb = container_of(w, struct nfsd4_callback,
- cb_work);
-
- nfsd4_prepare_cb_recall(to_delegation(cb));
- nfsd4_run_callback_rpc(cb);
+ cb->cb_ops ? &nfsd4_cb_ops : &nfsd4_cb_probe_ops, cb);
}

void nfsd4_init_cb(struct nfsd4_callback *cb, struct nfs4_client *clp,
- enum nfsd4_cb_op op)
+ struct nfsd4_callback_ops *ops, enum nfsd4_cb_op op)
{
cb->cb_clp = clp;
cb->cb_msg.rpc_proc = &nfs4_cb_procedures[op];
cb->cb_msg.rpc_argp = cb;
cb->cb_msg.rpc_resp = cb;
- if (op == NFSPROC4_CLNT_CB_NULL)
- cb->cb_ops = &nfsd4_cb_probe_ops;
- else
- cb->cb_ops = &nfsd4_cb_recall_ops;
+ cb->cb_ops = ops;
+ INIT_WORK(&cb->cb_work, nfsd4_run_cb_work);
INIT_LIST_HEAD(&cb->cb_per_client);
cb->cb_done = true;
}
diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
index 5e5012f..cf1ccc4 100644
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -96,6 +96,8 @@ static struct kmem_cache *deleg_slab;

static void free_session(struct nfsd4_session *);

+static struct nfsd4_callback_ops nfsd4_cb_recall_ops;
+
static bool is_session_dead(struct nfsd4_session *ses)
{
return ses->se_flags & NFS4_SESSION_DEAD;
@@ -652,8 +654,7 @@ alloc_init_deleg(struct nfs4_client *clp, struct svc_fh *current_fh)
dp->dl_type = NFS4_OPEN_DELEGATE_READ;
dp->dl_retries = 1;
nfsd4_init_cb(&dp->dl_recall, dp->dl_stid.sc_client,
- NFSPROC4_CLNT_CB_RECALL);
- INIT_WORK(&dp->dl_recall.cb_work, nfsd4_run_cb_recall);
+ &nfsd4_cb_recall_ops, NFSPROC4_CLNT_CB_RECALL);
return dp;
out_dec:
atomic_long_dec(&num_delegations);
@@ -1869,8 +1870,7 @@ static struct nfs4_client *create_client(struct xdr_netobj name,
free_client(clp);
return NULL;
}
- nfsd4_init_cb(&clp->cl_cb_null, clp, NFSPROC4_CLNT_CB_NULL);
- INIT_WORK(&clp->cl_cb_null.cb_work, nfsd4_run_cb_null);
+ nfsd4_init_cb(&clp->cl_cb_null, clp, NULL, NFSPROC4_CLNT_CB_NULL);
clp->cl_time = get_seconds();
clear_bit(0, &clp->cl_cb_slot_busy);
copy_verf(clp, verf);
@@ -3355,8 +3355,12 @@ nfs4_share_conflict(struct svc_fh *current_fh, unsigned int deny_type)
return ret;
}

-void nfsd4_prepare_cb_recall(struct nfs4_delegation *dp)
+#define cb_to_delegation(cb) \
+ container_of(cb, struct nfs4_delegation, dl_recall)
+
+static void nfsd4_cb_recall_prepare(struct nfsd4_callback *cb)
{
+ struct nfs4_delegation *dp = cb_to_delegation(cb);
struct nfsd_net *nn = net_generic(dp->dl_stid.sc_client->net,
nfsd_net_id);

@@ -3377,6 +3381,43 @@ void nfsd4_prepare_cb_recall(struct nfs4_delegation *dp)
spin_unlock(&state_lock);
}

+static int nfsd4_cb_recall_done(struct nfsd4_callback *cb,
+ struct rpc_task *task)
+{
+ struct nfs4_delegation *dp = cb_to_delegation(cb);
+
+ switch (task->tk_status) {
+ case 0:
+ return 1;
+ case -EBADHANDLE:
+ case -NFS4ERR_BAD_STATEID:
+ /*
+ * Race: client probably got cb_recall before open reply
+ * granting delegation.
+ */
+ if (dp->dl_retries--) {
+ rpc_delay(task, 2 * HZ);
+ return 0;
+ }
+ /*FALLTHRU*/
+ default:
+ return -1;
+ }
+}
+
+static void nfsd4_cb_recall_release(struct nfsd4_callback *cb)
+{
+ struct nfs4_delegation *dp = cb_to_delegation(cb);
+
+ nfs4_put_stid(&dp->dl_stid);
+}
+
+static struct nfsd4_callback_ops nfsd4_cb_recall_ops = {
+ .prepare = nfsd4_cb_recall_prepare,
+ .done = nfsd4_cb_recall_done,
+ .release = nfsd4_cb_recall_release,
+};
+
static void nfsd_break_one_deleg(struct nfs4_delegation *dp)
{
/*
diff --git a/fs/nfsd/state.h b/fs/nfsd/state.h
index 4d10e1d..f583ce4 100644
--- a/fs/nfsd/state.h
+++ b/fs/nfsd/state.h
@@ -66,11 +66,17 @@ struct nfsd4_callback {
struct list_head cb_per_client;
u32 cb_minorversion;
struct rpc_message cb_msg;
- const struct rpc_call_ops *cb_ops;
+ struct nfsd4_callback_ops *cb_ops;
struct work_struct cb_work;
bool cb_done;
};

+struct nfsd4_callback_ops {
+ void (*prepare)(struct nfsd4_callback *);
+ int (*done)(struct nfsd4_callback *, struct rpc_task *);
+ void (*release)(struct nfsd4_callback *);
+};
+
/*
* A core object that represents a "common" stateid. These are generally
* embedded within the different (more specific) stateid objects and contain
@@ -536,13 +542,11 @@ extern struct nfs4_client_reclaim *nfsd4_find_reclaim_client(const char *recdir,
extern __be32 nfs4_check_open_reclaim(clientid_t *clid,
struct nfsd4_compound_state *cstate, struct nfsd_net *nn);
extern int set_callback_cred(void);
-void nfsd4_run_cb_null(struct work_struct *w);
-void nfsd4_run_cb_recall(struct work_struct *w);
extern void nfsd4_probe_callback(struct nfs4_client *clp);
extern void nfsd4_probe_callback_sync(struct nfs4_client *clp);
extern void nfsd4_change_callback(struct nfs4_client *clp, struct nfs4_cb_conn *);
extern void nfsd4_init_cb(struct nfsd4_callback *cb, struct nfs4_client *clp,
- enum nfsd4_cb_op op);
+ struct nfsd4_callback_ops *ops, enum nfsd4_cb_op op);
extern void nfsd4_run_cb(struct nfsd4_callback *cb);
extern int nfsd4_create_callback_queue(void);
extern void nfsd4_destroy_callback_queue(void);
--
1.9.1