NLM: Remove "create" argument from nsm_find()
[safe/jmp/linux-2.6] / fs / lockd / mon.c
index 8130883..7407022 100644 (file)
 
 
 #define NLMDBG_FACILITY                NLMDBG_MONITOR
+#define NSM_PROGRAM            100024
+#define NSM_VERSION            1
+
+enum {
+       NSMPROC_NULL,
+       NSMPROC_STAT,
+       NSMPROC_MON,
+       NSMPROC_UNMON,
+       NSMPROC_UNMON_ALL,
+       NSMPROC_SIMU_CRASH,
+       NSMPROC_NOTIFY,
+};
 
 struct nsm_args {
-       __be32                  addr;           /* remote address */
+       struct nsm_private      *priv;
        u32                     prog;           /* RPC callback info */
        u32                     vers;
        u32                     proc;
@@ -35,14 +47,53 @@ struct nsm_res {
 static struct rpc_clnt *       nsm_create(void);
 
 static struct rpc_program      nsm_program;
+static                         LIST_HEAD(nsm_handles);
+static                         DEFINE_SPINLOCK(nsm_lock);
 
 /*
  * Local NSM state
  */
 int                            nsm_local_state;
 
+static void nsm_display_ipv4_address(const struct sockaddr *sap, char *buf,
+                                    const size_t len)
+{
+       const struct sockaddr_in *sin = (struct sockaddr_in *)sap;
+       snprintf(buf, len, "%pI4", &sin->sin_addr.s_addr);
+}
+
+static void nsm_display_ipv6_address(const struct sockaddr *sap, char *buf,
+                                    const size_t len)
+{
+       const struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sap;
+
+       if (ipv6_addr_v4mapped(&sin6->sin6_addr))
+               snprintf(buf, len, "%pI4", &sin6->sin6_addr.s6_addr32[3]);
+       else if (sin6->sin6_scope_id != 0)
+               snprintf(buf, len, "%pI6%%%u", &sin6->sin6_addr,
+                               sin6->sin6_scope_id);
+       else
+               snprintf(buf, len, "%pI6", &sin6->sin6_addr);
+}
+
+static void nsm_display_address(const struct sockaddr *sap,
+                               char *buf, const size_t len)
+{
+       switch (sap->sa_family) {
+       case AF_INET:
+               nsm_display_ipv4_address(sap, buf, len);
+               break;
+       case AF_INET6:
+               nsm_display_ipv6_address(sap, buf, len);
+               break;
+       default:
+               snprintf(buf, len, "unsupported address family");
+               break;
+       }
+}
+
 /*
- * Common procedure for SM_MON/SM_UNMON calls
+ * Common procedure for NSMPROC_MON/NSMPROC_UNMON calls
  */
 static int
 nsm_mon_unmon(struct nsm_handle *nsm, u32 proc, struct nsm_res *res)
@@ -50,7 +101,7 @@ nsm_mon_unmon(struct nsm_handle *nsm, u32 proc, struct nsm_res *res)
        struct rpc_clnt *clnt;
        int             status;
        struct nsm_args args = {
-               .addr           = nsm_addr_in(nsm)->sin_addr.s_addr,
+               .priv           = &nsm->sm_priv,
                .prog           = NLM_PROGRAM,
                .vers           = 3,
                .proc           = NLMPROC_NSM_NOTIFY,
@@ -111,7 +162,7 @@ int nsm_monitor(const struct nlm_host *host)
         */
        nsm->sm_mon_name = nsm_use_hostnames ? nsm->sm_name : nsm->sm_addrbuf;
 
-       status = nsm_mon_unmon(nsm, SM_MON, &res);
+       status = nsm_mon_unmon(nsm, NSMPROC_MON, &res);
        if (res.status != 0)
                status = -EIO;
        if (status < 0)
@@ -139,7 +190,7 @@ void nsm_unmonitor(const struct nlm_host *host)
         && nsm->sm_monitored && !nsm->sm_sticky) {
                dprintk("lockd: nsm_unmonitor(%s)\n", nsm->sm_name);
 
-               status = nsm_mon_unmon(nsm, SM_UNMON, &res);
+               status = nsm_mon_unmon(nsm, NSMPROC_UNMON, &res);
                if (res.status != 0)
                        status = -EIO;
                if (status < 0)
@@ -150,6 +201,177 @@ void nsm_unmonitor(const struct nlm_host *host)
        }
 }
 
+static struct nsm_handle *nsm_lookup_hostname(const char *hostname,
+                                             const size_t len)
+{
+       struct nsm_handle *nsm;
+
+       list_for_each_entry(nsm, &nsm_handles, sm_link)
+               if (strlen(nsm->sm_name) == len &&
+                   memcmp(nsm->sm_name, hostname, len) == 0)
+                       return nsm;
+       return NULL;
+}
+
+static struct nsm_handle *nsm_lookup_priv(const struct nsm_private *priv)
+{
+       struct nsm_handle *nsm;
+
+       list_for_each_entry(nsm, &nsm_handles, sm_link)
+               if (memcmp(nsm->sm_priv.data, priv->data,
+                                       sizeof(priv->data)) == 0)
+                       return nsm;
+       return NULL;
+}
+
+/*
+ * Construct a unique cookie to match this nsm_handle to this monitored
+ * host.  It is passed to the local rpc.statd via NSMPROC_MON, and
+ * returned via NLMPROC_SM_NOTIFY, in the "priv" field of these
+ * requests.
+ *
+ * Linux provides the raw IP address of the monitored host,
+ * left in network byte order.
+ */
+static void nsm_init_private(struct nsm_handle *nsm)
+{
+       __be32 *p = (__be32 *)&nsm->sm_priv.data;
+       *p = nsm_addr_in(nsm)->sin_addr.s_addr;
+}
+
+/**
+ * nsm_get_handle - Find or create a cached nsm_handle
+ * @sap: pointer to socket address of handle to find
+ * @salen: length of socket address
+ * @hostname: pointer to C string containing hostname to find
+ * @hostname_len: length of C string
+ *
+ * Behavior is modulated by the global nsm_use_hostnames variable.
+ *
+ * Returns a cached nsm_handle after bumping its ref count, or
+ * returns a fresh nsm_handle if a handle that matches @sap and/or
+ * @hostname cannot be found in the handle cache.  Returns NULL if
+ * an error occurs.
+ */
+struct nsm_handle *nsm_get_handle(const struct sockaddr *sap,
+                                 const size_t salen, const char *hostname,
+                                 const size_t hostname_len)
+{
+       struct nsm_handle *nsm = NULL;
+       struct nsm_handle *pos;
+
+       if (hostname && memchr(hostname, '/', hostname_len) != NULL) {
+               if (printk_ratelimit()) {
+                       printk(KERN_WARNING "Invalid hostname \"%.*s\" "
+                                           "in NFS lock request\n",
+                               (int)hostname_len, hostname);
+               }
+               return NULL;
+       }
+
+retry:
+       spin_lock(&nsm_lock);
+       list_for_each_entry(pos, &nsm_handles, sm_link) {
+
+               if (hostname && nsm_use_hostnames) {
+                       if (strlen(pos->sm_name) != hostname_len
+                        || memcmp(pos->sm_name, hostname, hostname_len))
+                               continue;
+               } else if (!nlm_cmp_addr(nsm_addr(pos), sap))
+                       continue;
+               atomic_inc(&pos->sm_count);
+               kfree(nsm);
+               nsm = pos;
+               dprintk("lockd: found nsm_handle for %s (%s), cnt %d\n",
+                               pos->sm_name, pos->sm_addrbuf,
+                               atomic_read(&pos->sm_count));
+               goto found;
+       }
+       if (nsm) {
+               list_add(&nsm->sm_link, &nsm_handles);
+               dprintk("lockd: created nsm_handle for %s (%s)\n",
+                               nsm->sm_name, nsm->sm_addrbuf);
+               goto found;
+       }
+       spin_unlock(&nsm_lock);
+
+       nsm = kzalloc(sizeof(*nsm) + hostname_len + 1, GFP_KERNEL);
+       if (nsm == NULL)
+               return NULL;
+
+       memcpy(nsm_addr(nsm), sap, salen);
+       nsm->sm_addrlen = salen;
+       nsm->sm_name = (char *) (nsm + 1);
+       memcpy(nsm->sm_name, hostname, hostname_len);
+       nsm->sm_name[hostname_len] = '\0';
+       nsm_init_private(nsm);
+       nsm_display_address((struct sockaddr *)&nsm->sm_addr,
+                               nsm->sm_addrbuf, sizeof(nsm->sm_addrbuf));
+       atomic_set(&nsm->sm_count, 1);
+       goto retry;
+
+found:
+       spin_unlock(&nsm_lock);
+       return nsm;
+}
+
+/**
+ * nsm_reboot_lookup - match NLMPROC_SM_NOTIFY arguments to an nsm_handle
+ * @info: pointer to NLMPROC_SM_NOTIFY arguments
+ *
+ * Returns a matching nsm_handle if found in the nsm cache; the returned
+ * nsm_handle's reference count is bumped and sm_monitored is cleared.
+ * Otherwise returns NULL if some error occurred.
+ */
+struct nsm_handle *nsm_reboot_lookup(const struct nlm_reboot *info)
+{
+       struct nsm_handle *cached;
+
+       spin_lock(&nsm_lock);
+
+       if (nsm_use_hostnames && info->mon != NULL)
+               cached = nsm_lookup_hostname(info->mon, info->len);
+       else
+               cached = nsm_lookup_priv(&info->priv);
+
+       if (unlikely(cached == NULL)) {
+               spin_unlock(&nsm_lock);
+               dprintk("lockd: never saw rebooted peer '%.*s' before\n",
+                               info->len, info->mon);
+               return cached;
+       }
+
+       atomic_inc(&cached->sm_count);
+       spin_unlock(&nsm_lock);
+
+       /*
+        * During subsequent lock activity, force a fresh
+        * notification to be set up for this host.
+        */
+       cached->sm_monitored = 0;
+
+       dprintk("lockd: host %s (%s) rebooted, cnt %d\n",
+                       cached->sm_name, cached->sm_addrbuf,
+                       atomic_read(&cached->sm_count));
+       return cached;
+}
+
+/**
+ * nsm_release - Release an NSM handle
+ * @nsm: pointer to handle to be released
+ *
+ */
+void nsm_release(struct nsm_handle *nsm)
+{
+       if (atomic_dec_and_lock(&nsm->sm_count, &nsm_lock)) {
+               list_del(&nsm->sm_link);
+               spin_unlock(&nsm_lock);
+               dprintk("lockd: destroyed nsm_handle for %s (%s)\n",
+                               nsm->sm_name, nsm->sm_addrbuf);
+               kfree(nsm);
+       }
+}
+
 /*
  * Create NSM client for the local host
  */
@@ -167,7 +389,7 @@ nsm_create(void)
                .addrsize       = sizeof(sin),
                .servername     = "localhost",
                .program        = &nsm_program,
-               .version        = SM_VERSION,
+               .version        = NSM_VERSION,
                .authflavor     = RPC_AUTH_NULL,
        };
 
@@ -181,112 +403,132 @@ nsm_create(void)
  * Status Monitor wire protocol.
  */
 
-static __be32 *xdr_encode_nsm_string(__be32 *p, char *string)
+static int encode_nsm_string(struct xdr_stream *xdr, const char *string)
 {
-       size_t len = strlen(string);
-
-       if (len > SM_MAXSTRLEN)
-               len = SM_MAXSTRLEN;
-       return xdr_encode_opaque(p, string, len);
+       const u32 len = strlen(string);
+       __be32 *p;
+
+       if (unlikely(len > SM_MAXSTRLEN))
+               return -EIO;
+       p = xdr_reserve_space(xdr, sizeof(u32) + len);
+       if (unlikely(p == NULL))
+               return -EIO;
+       xdr_encode_opaque(p, string, len);
+       return 0;
 }
 
 /*
  * "mon_name" specifies the host to be monitored.
  */
-static __be32 *xdr_encode_mon_name(__be32 *p, struct nsm_args *argp)
+static int encode_mon_name(struct xdr_stream *xdr, const struct nsm_args *argp)
 {
-       return xdr_encode_nsm_string(p, argp->mon_name);
+       return encode_nsm_string(xdr, argp->mon_name);
 }
 
 /*
  * The "my_id" argument specifies the hostname and RPC procedure
  * to be called when the status manager receives notification
- * (via the SM_NOTIFY call) that the state of host "mon_name"
+ * (via the NLMPROC_SM_NOTIFY call) that the state of host "mon_name"
  * has changed.
  */
-static __be32 *xdr_encode_my_id(__be32 *p, struct nsm_args *argp)
+static int encode_my_id(struct xdr_stream *xdr, const struct nsm_args *argp)
 {
-       p = xdr_encode_nsm_string(p, utsname()->nodename);
-       if (!p)
-               return ERR_PTR(-EIO);
-
+       int status;
+       __be32 *p;
+
+       status = encode_nsm_string(xdr, utsname()->nodename);
+       if (unlikely(status != 0))
+               return status;
+       p = xdr_reserve_space(xdr, 3 * sizeof(u32));
+       if (unlikely(p == NULL))
+               return -EIO;
        *p++ = htonl(argp->prog);
        *p++ = htonl(argp->vers);
        *p++ = htonl(argp->proc);
-
-       return p;
+       return 0;
 }
 
 /*
  * The "mon_id" argument specifies the non-private arguments
- * of an SM_MON or SM_UNMON call.
+ * of an NSMPROC_MON or NSMPROC_UNMON call.
  */
-static __be32 *xdr_encode_mon_id(__be32 *p, struct nsm_args *argp)
+static int encode_mon_id(struct xdr_stream *xdr, const struct nsm_args *argp)
 {
-       p = xdr_encode_mon_name(p, argp);
-       if (!p)
-               return ERR_PTR(-EIO);
+       int status;
 
-       return xdr_encode_my_id(p, argp);
+       status = encode_mon_name(xdr, argp);
+       if (unlikely(status != 0))
+               return status;
+       return encode_my_id(xdr, argp);
 }
 
 /*
  * The "priv" argument may contain private information required
- * by the SM_MON call. This information will be supplied in the
- * SM_NOTIFY call.
- *
- * Linux provides the raw IP address of the monitored host,
- * left in network byte order.
+ * by the NSMPROC_MON call. This information will be supplied in the
+ * NLMPROC_SM_NOTIFY call.
  */
-static __be32 *xdr_encode_priv(__be32 *p, struct nsm_args *argp)
+static int encode_priv(struct xdr_stream *xdr, const struct nsm_args *argp)
 {
-       *p++ = argp->addr;
-       *p++ = 0;
-       *p++ = 0;
-       *p++ = 0;
+       __be32 *p;
 
-       return p;
+       p = xdr_reserve_space(xdr, SM_PRIV_SIZE);
+       if (unlikely(p == NULL))
+               return -EIO;
+       xdr_encode_opaque_fixed(p, argp->priv->data, SM_PRIV_SIZE);
+       return 0;
 }
 
-static int
-xdr_encode_mon(struct rpc_rqst *rqstp, __be32 *p, struct nsm_args *argp)
+static int xdr_enc_mon(struct rpc_rqst *req, __be32 *p,
+                      const struct nsm_args *argp)
 {
-       p = xdr_encode_mon_id(p, argp);
-       if (IS_ERR(p))
-               return PTR_ERR(p);
-
-       p = xdr_encode_priv(p, argp);
-       if (IS_ERR(p))
-               return PTR_ERR(p);
+       struct xdr_stream xdr;
+       int status;
 
-       rqstp->rq_slen = xdr_adjust_iovec(rqstp->rq_svec, p);
-       return 0;
+       xdr_init_encode(&xdr, &req->rq_snd_buf, p);
+       status = encode_mon_id(&xdr, argp);
+       if (unlikely(status))
+               return status;
+       return encode_priv(&xdr, argp);
 }
 
-static int
-xdr_encode_unmon(struct rpc_rqst *rqstp, __be32 *p, struct nsm_args *argp)
+static int xdr_enc_unmon(struct rpc_rqst *req, __be32 *p,
+                        const struct nsm_args *argp)
 {
-       p = xdr_encode_mon_id(p, argp);
-       if (IS_ERR(p))
-               return PTR_ERR(p);
-       rqstp->rq_slen = xdr_adjust_iovec(rqstp->rq_svec, p);
-       return 0;
+       struct xdr_stream xdr;
+
+       xdr_init_encode(&xdr, &req->rq_snd_buf, p);
+       return encode_mon_id(&xdr, argp);
 }
 
-static int
-xdr_decode_stat_res(struct rpc_rqst *rqstp, __be32 *p, struct nsm_res *resp)
+static int xdr_dec_stat_res(struct rpc_rqst *rqstp, __be32 *p,
+                           struct nsm_res *resp)
 {
+       struct xdr_stream xdr;
+
+       xdr_init_decode(&xdr, &rqstp->rq_rcv_buf, p);
+       p = xdr_inline_decode(&xdr, 2 * sizeof(u32));
+       if (unlikely(p == NULL))
+               return -EIO;
        resp->status = ntohl(*p++);
-       resp->state = ntohl(*p++);
-       dprintk("nsm: xdr_decode_stat_res status %d state %d\n",
+       resp->state = ntohl(*p);
+
+       dprintk("lockd: xdr_dec_stat_res status %d state %d\n",
                        resp->status, resp->state);
        return 0;
 }
 
-static int
-xdr_decode_stat(struct rpc_rqst *rqstp, __be32 *p, struct nsm_res *resp)
+static int xdr_dec_stat(struct rpc_rqst *rqstp, __be32 *p,
+                       struct nsm_res *resp)
 {
-       resp->state = ntohl(*p++);
+       struct xdr_stream xdr;
+
+       xdr_init_decode(&xdr, &rqstp->rq_rcv_buf, p);
+       p = xdr_inline_decode(&xdr, sizeof(u32));
+       if (unlikely(p == NULL))
+               return -EIO;
+       resp->state = ntohl(*p);
+
+       dprintk("lockd: xdr_dec_stat state %d\n", resp->state);
        return 0;
 }
 
@@ -300,22 +542,22 @@ xdr_decode_stat(struct rpc_rqst *rqstp, __be32 *p, struct nsm_res *resp)
 #define SM_unmonres_sz 1
 
 static struct rpc_procinfo     nsm_procedures[] = {
-[SM_MON] = {
-               .p_proc         = SM_MON,
-               .p_encode       = (kxdrproc_t) xdr_encode_mon,
-               .p_decode       = (kxdrproc_t) xdr_decode_stat_res,
+[NSMPROC_MON] = {
+               .p_proc         = NSMPROC_MON,
+               .p_encode       = (kxdrproc_t)xdr_enc_mon,
+               .p_decode       = (kxdrproc_t)xdr_dec_stat_res,
                .p_arglen       = SM_mon_sz,
                .p_replen       = SM_monres_sz,
-               .p_statidx      = SM_MON,
+               .p_statidx      = NSMPROC_MON,
                .p_name         = "MONITOR",
        },
-[SM_UNMON] = {
-               .p_proc         = SM_UNMON,
-               .p_encode       = (kxdrproc_t) xdr_encode_unmon,
-               .p_decode       = (kxdrproc_t) xdr_decode_stat,
+[NSMPROC_UNMON] = {
+               .p_proc         = NSMPROC_UNMON,
+               .p_encode       = (kxdrproc_t)xdr_enc_unmon,
+               .p_decode       = (kxdrproc_t)xdr_dec_stat,
                .p_arglen       = SM_mon_id_sz,
                .p_replen       = SM_unmonres_sz,
-               .p_statidx      = SM_UNMON,
+               .p_statidx      = NSMPROC_UNMON,
                .p_name         = "UNMONITOR",
        },
 };
@@ -334,7 +576,7 @@ static struct rpc_stat              nsm_stats;
 
 static struct rpc_program      nsm_program = {
                .name           = "statd",
-               .number         = SM_PROGRAM,
+               .number         = NSM_PROGRAM,
                .nrvers         = ARRAY_SIZE(nsm_version),
                .version        = nsm_version,
                .stats          = &nsm_stats