pNFS: return status from nfs4_pnfs_ds_connect

The nfs4_pnfs_ds_connect path can call rpc_create which can fail or it
can wait on another context to reach the same failure.

This checks that the rpc_create succeeded and returns the error to the
caller.

When an error is returned, both the files and flexfiles layouts will return
NULL from _prepare_ds(). The flexfiles layout will also return the layout
with the error NFS4ERR_NXIO.

Signed-off-by: Weston Andros Adamson <dros@primarydata.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

diff --git a/fs/nfs/client.c b/fs/nfs/client.c
index 91a8d61..390ada8 100644 (file)
--- a/fs/nfs/client.c
+++ b/fs/nfs/client.c
@@ -325,10 +325,33 @@ static struct nfs_client *nfs_match_client(const struct nfs_client_initdata *dat
        return NULL;
 }
 
-static bool nfs_client_init_is_complete(const struct nfs_client *clp)
+/*
+ * Return true if @clp is done initializing, false if still working on it.
+ *
+ * Use nfs_client_init_status to check if it was successful.
+ */
+bool nfs_client_init_is_complete(const struct nfs_client *clp)
 {
        return clp->cl_cons_state <= NFS_CS_READY;
 }
+EXPORT_SYMBOL_GPL(nfs_client_init_is_complete);
+
+/*
+ * Return 0 if @clp was successfully initialized, -errno otherwise.
+ *
+ * This must be called *after* nfs_client_init_is_complete() returns true,
+ * otherwise it will pop WARN_ON_ONCE and return -EINVAL
+ */
+int nfs_client_init_status(const struct nfs_client *clp)
+{
+       /* called without checking nfs_client_init_is_complete */
+       if (clp->cl_cons_state > NFS_CS_READY) {
+               WARN_ON_ONCE(1);
+               return -EINVAL;
+       }
+       return clp->cl_cons_state;
+}
+EXPORT_SYMBOL_GPL(nfs_client_init_status);
 
 int nfs_wait_client_init_complete(const struct nfs_client *clp)
 {

diff --git a/fs/nfs/filelayout/filelayoutdev.c b/fs/nfs/filelayout/filelayoutdev.c
index f956ca2..1881206 100644 (file)
--- a/fs/nfs/filelayout/filelayoutdev.c
+++ b/fs/nfs/filelayout/filelayoutdev.c
@@ -266,6 +266,7 @@ nfs4_fl_prepare_ds(struct pnfs_layout_segment *lseg, u32 ds_idx)
        struct nfs4_deviceid_node *devid = FILELAYOUT_DEVID_NODE(lseg);
        struct nfs4_pnfs_ds *ret = ds;
        struct nfs_server *s = NFS_SERVER(lseg->pls_layout->plh_inode);
+       int status;
 
        if (ds == NULL) {
                printk(KERN_ERR "NFS: %s: No data server for offset index %d\n",
@@ -277,9 +278,13 @@ nfs4_fl_prepare_ds(struct pnfs_layout_segment *lseg, u32 ds_idx)
        if (ds->ds_clp)
                goto out_test_devid;
 
-       nfs4_pnfs_ds_connect(s, ds, devid, dataserver_timeo,
+       status = nfs4_pnfs_ds_connect(s, ds, devid, dataserver_timeo,
                             dataserver_retrans, 4,
                             s->nfs_client->cl_minorversion);
+       if (status) {
+               ret = NULL;
+               goto out;
+       }
 
 out_test_devid:
        if (ret->ds_clp == NULL ||

diff --git a/fs/nfs/flexfilelayout/flexfilelayoutdev.c b/fs/nfs/flexfilelayout/flexfilelayoutdev.c
index e5a6f24..544e772 100644 (file)
--- a/fs/nfs/flexfilelayout/flexfilelayoutdev.c
+++ b/fs/nfs/flexfilelayout/flexfilelayoutdev.c
@@ -384,6 +384,7 @@ nfs4_ff_layout_prepare_ds(struct pnfs_layout_segment *lseg, u32 ds_idx,
        struct inode *ino = lseg->pls_layout->plh_inode;
        struct nfs_server *s = NFS_SERVER(ino);
        unsigned int max_payload;
+       int status;
 
        if (!ff_layout_mirror_valid(lseg, mirror, true)) {
                pr_err_ratelimited("NFS: %s: No data server for offset index %d\n",
@@ -404,7 +405,7 @@ nfs4_ff_layout_prepare_ds(struct pnfs_layout_segment *lseg, u32 ds_idx,
        /* FIXME: For now we assume the server sent only one version of NFS
         * to use for the DS.
         */
-       nfs4_pnfs_ds_connect(s, ds, devid, dataserver_timeo,
+       status = nfs4_pnfs_ds_connect(s, ds, devid, dataserver_timeo,
                             dataserver_retrans,
                             mirror->mirror_ds->ds_versions[0].version,
                             mirror->mirror_ds->ds_versions[0].minor_version);

diff --git a/fs/nfs/internal.h b/fs/nfs/internal.h
index 09ca509..7b38fed 100644 (file)
--- a/fs/nfs/internal.h
+++ b/fs/nfs/internal.h
@@ -186,6 +186,8 @@ extern struct nfs_server *nfs_clone_server(struct nfs_server *,
                                           struct nfs_fh *,
                                           struct nfs_fattr *,
                                           rpc_authflavor_t);
+extern bool nfs_client_init_is_complete(const struct nfs_client *clp);
+extern int nfs_client_init_status(const struct nfs_client *clp);
 extern int nfs_wait_client_init_complete(const struct nfs_client *clp);
 extern void nfs_mark_client_ready(struct nfs_client *clp, int state);
 extern struct nfs_client *nfs4_set_ds_client(struct nfs_server *mds_srv,

diff --git a/fs/nfs/pnfs.h b/fs/nfs/pnfs.h
index 63f77b4..590e1e3 100644 (file)
--- a/fs/nfs/pnfs.h
+++ b/fs/nfs/pnfs.h
@@ -367,7 +367,7 @@ void nfs4_pnfs_ds_put(struct nfs4_pnfs_ds *ds);
 struct nfs4_pnfs_ds *nfs4_pnfs_ds_add(struct list_head *dsaddrs,
                                      gfp_t gfp_flags);
 void nfs4_pnfs_v3_ds_connect_unload(void);
-void nfs4_pnfs_ds_connect(struct nfs_server *mds_srv, struct nfs4_pnfs_ds *ds,
+int nfs4_pnfs_ds_connect(struct nfs_server *mds_srv, struct nfs4_pnfs_ds *ds,
                          struct nfs4_deviceid_node *devid, unsigned int timeo,
                          unsigned int retrans, u32 version, u32 minor_version);
 struct nfs4_pnfs_ds_addr *nfs4_decode_mp_ds_addr(struct net *net,

diff --git a/fs/nfs/pnfs_nfs.c b/fs/nfs/pnfs_nfs.c
index 9414b49..a7691b9 100644 (file)
--- a/fs/nfs/pnfs_nfs.c
+++ b/fs/nfs/pnfs_nfs.c
@@ -745,9 +745,9 @@ out:
 /*
  * Create an rpc connection to the nfs4_pnfs_ds data server.
  * Currently only supports IPv4 and IPv6 addresses.
- * If connection fails, make devid unavailable.
+ * If connection fails, make devid unavailable and return a -errno.
  */
-void nfs4_pnfs_ds_connect(struct nfs_server *mds_srv, struct nfs4_pnfs_ds *ds,
+int nfs4_pnfs_ds_connect(struct nfs_server *mds_srv, struct nfs4_pnfs_ds *ds,
                          struct nfs4_deviceid_node *devid, unsigned int timeo,
                          unsigned int retrans, u32 version, u32 minor_version)
 {
@@ -772,6 +772,17 @@ void nfs4_pnfs_ds_connect(struct nfs_server *mds_srv, struct nfs4_pnfs_ds *ds,
        } else {
                nfs4_wait_ds_connect(ds);
        }
+
+       /*
+        * At this point the ds->ds_clp should be ready, but it might have
+        * hit an error.
+        */
+       if (!ds->ds_clp || !nfs_client_init_is_complete(ds->ds_clp)) {
+               WARN_ON_ONCE(1);
+               return -EINVAL;
+       }
+
+       return nfs_client_init_status(ds->ds_clp);
 }
 EXPORT_SYMBOL_GPL(nfs4_pnfs_ds_connect);