SUNRPC: Make RPC portmapper use per-transport storage
Move connection and bind state that was maintained in the rpc_clnt
structure to the rpc_xprt structure. This will allow the creation of
a clean API for plugging in different types of bind mechanisms.
This brings improvements such as the elimination of a single spin lock to
control serialization for all in-kernel RPC binding. A set of per-xprt
bitops is used to serialize tasks during RPC binding, just like it now
works for making RPC transport connections.
Test-plan:
Destructive testing (unplugging the network temporarily). Connectathon
with UDP and TCP. NFSv2/3 and NFSv4 mounting should be carefully checked.
Probably need to rig a server where certain services aren't running, or
that returns an error for some typical operation.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
diff --git a/include/linux/sunrpc/clnt.h b/include/linux/sunrpc/clnt.h
index 8fe9f35..00e9dba 100644
--- a/include/linux/sunrpc/clnt.h
+++ b/include/linux/sunrpc/clnt.h
@@ -18,18 +18,6 @@
#include <linux/sunrpc/timer.h>
#include <asm/signal.h>
-/*
- * This defines an RPC port mapping
- */
-struct rpc_portmap {
- __u32 pm_prog;
- __u32 pm_vers;
- __u32 pm_prot;
- __u16 pm_port;
- unsigned char pm_binding : 1; /* doing a getport() */
- struct rpc_wait_queue pm_bindwait; /* waiting on getport() */
-};
-
struct rpc_inode;
/*
@@ -40,7 +28,9 @@
atomic_t cl_users; /* number of references */
struct rpc_xprt * cl_xprt; /* transport */
struct rpc_procinfo * cl_procinfo; /* procedure info */
- u32 cl_maxproc; /* max procedure number */
+ u32 cl_prog, /* RPC program number */
+ cl_vers, /* RPC version number */
+ cl_maxproc; /* max procedure number */
char * cl_server; /* server machine name */
char * cl_protname; /* protocol name */
@@ -55,7 +45,6 @@
cl_dead : 1;/* abandoned */
struct rpc_rtt * cl_rtt; /* RTO estimator data */
- struct rpc_portmap * cl_pmap; /* port mapping */
int cl_nodelen; /* nodename length */
char cl_nodename[UNX_MAXNODENAME];
@@ -64,14 +53,8 @@
struct dentry * cl_dentry; /* inode */
struct rpc_clnt * cl_parent; /* Points to parent of clones */
struct rpc_rtt cl_rtt_default;
- struct rpc_portmap cl_pmap_default;
char cl_inline_name[32];
};
-#define cl_timeout cl_xprt->timeout
-#define cl_prog cl_pmap->pm_prog
-#define cl_vers cl_pmap->pm_vers
-#define cl_port cl_pmap->pm_port
-#define cl_prot cl_pmap->pm_prot
/*
* General RPC program info
diff --git a/include/linux/sunrpc/xprt.h b/include/linux/sunrpc/xprt.h
index a711067..4ce8261 100644
--- a/include/linux/sunrpc/xprt.h
+++ b/include/linux/sunrpc/xprt.h
@@ -138,6 +138,7 @@
unsigned int tsh_size; /* size of transport specific
header */
+ struct rpc_wait_queue binding; /* requests waiting on rpcbind */
struct rpc_wait_queue sending; /* requests waiting to send */
struct rpc_wait_queue resend; /* requests waiting to resend */
struct rpc_wait_queue pending; /* requests in flight */
@@ -270,6 +271,7 @@
#define XPRT_CONNECTING (2)
#define XPRT_CLOSE_WAIT (3)
#define XPRT_BOUND (4)
+#define XPRT_BINDING (5)
static inline void xprt_set_connected(struct rpc_xprt *xprt)
{
@@ -328,6 +330,18 @@
clear_bit(XPRT_BOUND, &xprt->state);
}
+static inline void xprt_clear_binding(struct rpc_xprt *xprt)
+{
+ smp_mb__before_clear_bit();
+ clear_bit(XPRT_BINDING, &xprt->state);
+ smp_mb__after_clear_bit();
+}
+
+static inline int xprt_test_and_set_binding(struct rpc_xprt *xprt)
+{
+ return test_and_set_bit(XPRT_BINDING, &xprt->state);
+}
+
#endif /* __KERNEL__*/
#endif /* _LINUX_SUNRPC_XPRT_H */
diff --git a/net/sunrpc/clnt.c b/net/sunrpc/clnt.c
index 0b8d03d..cee5041 100644
--- a/net/sunrpc/clnt.c
+++ b/net/sunrpc/clnt.c
@@ -147,13 +147,10 @@
clnt->cl_procinfo = version->procs;
clnt->cl_maxproc = version->nrprocs;
clnt->cl_protname = program->name;
- clnt->cl_pmap = &clnt->cl_pmap_default;
clnt->cl_prog = program->number;
clnt->cl_vers = version->number;
- clnt->cl_prot = xprt->prot;
clnt->cl_stats = program->stats;
clnt->cl_metrics = rpc_alloc_iostats(clnt);
- rpc_init_wait_queue(&clnt->cl_pmap_default.pm_bindwait, "bindwait");
if (!xprt_bound(clnt->cl_xprt))
clnt->cl_autobind = 1;
@@ -243,8 +240,6 @@
atomic_set(&new->cl_users, 0);
new->cl_parent = clnt;
atomic_inc(&clnt->cl_count);
- /* Duplicate portmapper */
- rpc_init_wait_queue(&new->cl_pmap_default.pm_bindwait, "bindwait");
/* Turn off autobind on clones */
new->cl_autobind = 0;
new->cl_oneshot = 0;
@@ -254,8 +249,7 @@
rpc_init_rtt(&new->cl_rtt_default, clnt->cl_xprt->timeout.to_initval);
if (new->cl_auth)
atomic_inc(&new->cl_auth->au_count);
- new->cl_pmap = &new->cl_pmap_default;
- new->cl_metrics = rpc_alloc_iostats(clnt);
+ new->cl_metrics = rpc_alloc_iostats(clnt);
return new;
out_no_clnt:
printk(KERN_INFO "RPC: out of memory in %s\n", __FUNCTION__);
diff --git a/net/sunrpc/pmap_clnt.c b/net/sunrpc/pmap_clnt.c
index 209ffdf..59d5424 100644
--- a/net/sunrpc/pmap_clnt.c
+++ b/net/sunrpc/pmap_clnt.c
@@ -24,11 +24,57 @@
#define PMAP_UNSET 2
#define PMAP_GETPORT 3
+struct portmap_args {
+ u32 pm_prog;
+ u32 pm_vers;
+ u32 pm_prot;
+ unsigned short pm_port;
+ struct rpc_task * pm_task;
+};
+
static struct rpc_procinfo pmap_procedures[];
static struct rpc_clnt * pmap_create(char *, struct sockaddr_in *, int, int);
-static void pmap_getport_done(struct rpc_task *);
+static void pmap_getport_done(struct rpc_task *, void *);
static struct rpc_program pmap_program;
-static DEFINE_SPINLOCK(pmap_lock);
+
+static void pmap_getport_prepare(struct rpc_task *task, void *calldata)
+{
+ struct portmap_args *map = calldata;
+ struct rpc_message msg = {
+ .rpc_proc = &pmap_procedures[PMAP_GETPORT],
+ .rpc_argp = map,
+ .rpc_resp = &map->pm_port,
+ };
+
+ rpc_call_setup(task, &msg, 0);
+}
+
+static inline struct portmap_args *pmap_map_alloc(void)
+{
+ return kmalloc(sizeof(struct portmap_args), GFP_NOFS);
+}
+
+static inline void pmap_map_free(struct portmap_args *map)
+{
+ kfree(map);
+}
+
+static void pmap_map_release(void *data)
+{
+ pmap_map_free(data);
+}
+
+static const struct rpc_call_ops pmap_getport_ops = {
+ .rpc_call_prepare = pmap_getport_prepare,
+ .rpc_call_done = pmap_getport_done,
+ .rpc_release = pmap_map_release,
+};
+
+static inline void pmap_wake_portmap_waiters(struct rpc_xprt *xprt)
+{
+ xprt_clear_binding(xprt);
+ rpc_wake_up(&xprt->binding);
+}
/*
* Obtain the port for a given RPC service on a given host. This one can
@@ -37,67 +83,71 @@
void
rpc_getport(struct rpc_task *task, struct rpc_clnt *clnt)
{
- struct rpc_portmap *map = clnt->cl_pmap;
- struct sockaddr_in *sap = &clnt->cl_xprt->addr;
- struct rpc_message msg = {
- .rpc_proc = &pmap_procedures[PMAP_GETPORT],
- .rpc_argp = map,
- .rpc_resp = &clnt->cl_port,
- .rpc_cred = NULL
- };
+ struct rpc_xprt *xprt = task->tk_xprt;
+ struct sockaddr_in *sap = &xprt->addr;
+ struct portmap_args *map;
struct rpc_clnt *pmap_clnt;
- struct rpc_task *child;
+ struct rpc_task *child;
- dprintk("RPC: %4d rpc_getport(%s, %d, %d, %d)\n",
+ dprintk("RPC: %4d rpc_getport(%s, %u, %u, %d)\n",
task->tk_pid, clnt->cl_server,
- map->pm_prog, map->pm_vers, map->pm_prot);
+ clnt->cl_prog, clnt->cl_vers, xprt->prot);
/* Autobind on cloned rpc clients is discouraged */
BUG_ON(clnt->cl_parent != clnt);
- spin_lock(&pmap_lock);
- if (map->pm_binding) {
- rpc_sleep_on(&map->pm_bindwait, task, NULL, NULL);
- spin_unlock(&pmap_lock);
+ if (xprt_test_and_set_binding(xprt)) {
+ task->tk_status = -EACCES; /* tell caller to check again */
+ rpc_sleep_on(&xprt->binding, task, NULL, NULL);
return;
}
- map->pm_binding = 1;
- spin_unlock(&pmap_lock);
+
+ /* Someone else may have bound if we slept */
+ if (xprt_bound(xprt)) {
+ task->tk_status = 0;
+ goto bailout_nofree;
+ }
+
+ map = pmap_map_alloc();
+ if (!map) {
+ task->tk_status = -ENOMEM;
+ goto bailout_nofree;
+ }
+ map->pm_prog = clnt->cl_prog;
+ map->pm_vers = clnt->cl_vers;
+ map->pm_prot = xprt->prot;
+ map->pm_port = 0;
+ map->pm_task = task;
pmap_clnt = pmap_create(clnt->cl_server, sap, map->pm_prot, 0);
if (IS_ERR(pmap_clnt)) {
task->tk_status = PTR_ERR(pmap_clnt);
goto bailout;
}
- task->tk_status = 0;
- /*
- * Note: rpc_new_child will release client after a failure.
- */
- if (!(child = rpc_new_child(pmap_clnt, task)))
+ child = rpc_run_task(pmap_clnt, RPC_TASK_ASYNC, &pmap_getport_ops, map);
+ if (IS_ERR(child)) {
+ task->tk_status = -EIO;
goto bailout;
+ }
+ rpc_release_task(child);
- /* Setup the call info struct */
- rpc_call_setup(child, &msg, 0);
+ rpc_sleep_on(&xprt->binding, task, NULL, NULL);
- /* ... and run the child task */
task->tk_xprt->stat.bind_count++;
- rpc_run_child(task, child, pmap_getport_done);
return;
bailout:
- spin_lock(&pmap_lock);
- map->pm_binding = 0;
- rpc_wake_up(&map->pm_bindwait);
- spin_unlock(&pmap_lock);
- rpc_exit(task, -EIO);
+ pmap_map_free(map);
+bailout_nofree:
+ pmap_wake_portmap_waiters(xprt);
}
#ifdef CONFIG_ROOT_NFS
int
rpc_getport_external(struct sockaddr_in *sin, __u32 prog, __u32 vers, int prot)
{
- struct rpc_portmap map = {
+ struct portmap_args map = {
.pm_prog = prog,
.pm_vers = vers,
.pm_prot = prot,
@@ -133,32 +183,32 @@
#endif
static void
-pmap_getport_done(struct rpc_task *task)
+pmap_getport_done(struct rpc_task *child, void *data)
{
- struct rpc_clnt *clnt = task->tk_client;
+ struct portmap_args *map = data;
+ struct rpc_task *task = map->pm_task;
struct rpc_xprt *xprt = task->tk_xprt;
- struct rpc_portmap *map = clnt->cl_pmap;
+ int status = child->tk_status;
- dprintk("RPC: %4d pmap_getport_done(status %d, port %d)\n",
- task->tk_pid, task->tk_status, clnt->cl_port);
-
- if (task->tk_status < 0) {
- /* Make the calling task exit with an error */
+ if (status < 0) {
+ /* Portmapper not available */
xprt->ops->set_port(xprt, 0);
- task->tk_action = rpc_exit_task;
- } else if (clnt->cl_port == 0) {
- /* Program not registered */
+ task->tk_status = status;
+ } else if (map->pm_port == 0) {
+ /* Requested RPC service wasn't registered */
xprt->ops->set_port(xprt, 0);
- rpc_exit(task, -EACCES);
+ task->tk_status = -EACCES;
} else {
- xprt->ops->set_port(xprt, clnt->cl_port);
+ /* Succeeded */
+ xprt->ops->set_port(xprt, map->pm_port);
xprt_set_bound(xprt);
- clnt->cl_port = htons(clnt->cl_port);
+ task->tk_status = 0;
}
- spin_lock(&pmap_lock);
- map->pm_binding = 0;
- rpc_wake_up(&map->pm_bindwait);
- spin_unlock(&pmap_lock);
+
+ dprintk("RPC: %4d pmap_getport_done(status %d, port %u)\n",
+ child->tk_pid, child->tk_status, map->pm_port);
+
+ pmap_wake_portmap_waiters(xprt);
}
/*
@@ -172,7 +222,7 @@
.sin_family = AF_INET,
.sin_addr.s_addr = htonl(INADDR_LOOPBACK),
};
- struct rpc_portmap map = {
+ struct portmap_args map = {
.pm_prog = prog,
.pm_vers = vers,
.pm_prot = prot,
@@ -239,7 +289,7 @@
* XDR encode/decode functions for PMAP
*/
static int
-xdr_encode_mapping(struct rpc_rqst *req, u32 *p, struct rpc_portmap *map)
+xdr_encode_mapping(struct rpc_rqst *req, u32 *p, struct portmap_args *map)
{
dprintk("RPC: xdr_encode_mapping(%d, %d, %d, %d)\n",
map->pm_prog, map->pm_vers, map->pm_prot, map->pm_port);
diff --git a/net/sunrpc/xprt.c b/net/sunrpc/xprt.c
index e239ef9..b45abd0 100644
--- a/net/sunrpc/xprt.c
+++ b/net/sunrpc/xprt.c
@@ -928,6 +928,7 @@
xprt->last_used = jiffies;
xprt->cwnd = RPC_INITCWND;
+ rpc_init_wait_queue(&xprt->binding, "xprt_binding");
rpc_init_wait_queue(&xprt->pending, "xprt_pending");
rpc_init_wait_queue(&xprt->sending, "xprt_sending");
rpc_init_wait_queue(&xprt->resend, "xprt_resend");