Linux-libre 4.7.1-gnupck-4.7.1-gnu

1 files changed, 60 insertions, 59 deletions

diff --git a/fs/nfs/flexfilelayout/flexfilelayoutdev.c b/fs/nfs/flexfilelayout/flexfilelayoutdev.c
index add0e5a70..0aa36be71 100644
--- a/fs/nfs/flexfilelayout/flexfilelayoutdev.c
+++ b/fs/nfs/flexfilelayout/flexfilelayoutdev.c
@@ -228,7 +228,8 @@ ff_ds_error_match(const struct nfs4_ff_layout_ds_err *e1,
 		return e1->opnum < e2->opnum ? -1 : 1;
 	if (e1->status != e2->status)
 		return e1->status < e2->status ? -1 : 1;
-	ret = memcmp(&e1->stateid, &e2->stateid, sizeof(e1->stateid));
+	ret = memcmp(e1->stateid.data, e2->stateid.data,
+			sizeof(e1->stateid.data));
 	if (ret != 0)
 		return ret;
 	ret = memcmp(&e1->deviceid, &e2->deviceid, sizeof(e1->deviceid));
@@ -302,40 +303,26 @@ int ff_layout_track_ds_error(struct nfs4_flexfile_layout *flo,
 	return 0;
 }
 
-/* currently we only support AUTH_NONE and AUTH_SYS */
-static rpc_authflavor_t
-nfs4_ff_layout_choose_authflavor(struct nfs4_ff_layout_mirror *mirror)
+static struct rpc_cred *
+ff_layout_get_mirror_cred(struct nfs4_ff_layout_mirror *mirror, u32 iomode)
 {
-	if (mirror->uid == (u32)-1)
-		return RPC_AUTH_NULL;
-	return RPC_AUTH_UNIX;
-}
+	struct rpc_cred *cred, __rcu **pcred;
 
-/* fetch cred for NFSv3 DS */
-static int ff_layout_update_mirror_cred(struct nfs4_ff_layout_mirror *mirror,
-				      struct nfs4_pnfs_ds *ds)
-{
-	if (ds->ds_clp && !mirror->cred &&
-	    mirror->mirror_ds->ds_versions[0].version == 3) {
-		struct rpc_auth *auth = ds->ds_clp->cl_rpcclient->cl_auth;
-		struct rpc_cred *cred;
-		struct auth_cred acred = {
-			.uid = make_kuid(&init_user_ns, mirror->uid),
-			.gid = make_kgid(&init_user_ns, mirror->gid),
-		};
-
-		/* AUTH_NULL ignores acred */
-		cred = auth->au_ops->lookup_cred(auth, &acred, 0);
-		if (IS_ERR(cred)) {
-			dprintk("%s: lookup_cred failed with %ld\n",
-				__func__, PTR_ERR(cred));
-			return PTR_ERR(cred);
-		} else {
-			if (cmpxchg(&mirror->cred, NULL, cred))
-				put_rpccred(cred);
-		}
-	}
-	return 0;
+	if (iomode == IOMODE_READ)
+		pcred = &mirror->ro_cred;
+	else
+		pcred = &mirror->rw_cred;
+
+	rcu_read_lock();
+	do {
+		cred = rcu_dereference(*pcred);
+		if (!cred)
+			break;
+
+		cred = get_rpccred_rcu(cred);
+	} while(!cred);
+	rcu_read_unlock();
+	return cred;
 }
 
 struct nfs_fh *
@@ -356,7 +343,23 @@ out:
 	return fh;
 }
 
-/* Upon return, either ds is connected, or ds is NULL */
+/**
+ * nfs4_ff_layout_prepare_ds - prepare a DS connection for an RPC call
+ * @lseg: the layout segment we're operating on
+ * @ds_idx: index of the DS to use
+ * @fail_return: return layout on connect failure?
+ *
+ * Try to prepare a DS connection to accept an RPC call. This involves
+ * selecting a mirror to use and connecting the client to it if it's not
+ * already connected.
+ *
+ * Since we only need a single functioning mirror to satisfy a read, we don't
+ * want to return the layout if there is one. For writes though, any down
+ * mirror should result in a LAYOUTRETURN. @fail_return is how we distinguish
+ * between the two cases.
+ *
+ * Returns a pointer to a connected DS object on success or NULL on failure.
+ */
 struct nfs4_pnfs_ds *
 nfs4_ff_layout_prepare_ds(struct pnfs_layout_segment *lseg, u32 ds_idx,
 			  bool fail_return)
@@ -367,7 +370,6 @@ 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;
-	rpc_authflavor_t flavor;
 
 	if (!ff_layout_mirror_valid(lseg, mirror)) {
 		pr_err_ratelimited("NFS: %s: No data server for offset index %d\n",
@@ -383,9 +385,7 @@ nfs4_ff_layout_prepare_ds(struct pnfs_layout_segment *lseg, u32 ds_idx,
 	/* matching smp_wmb() in _nfs4_pnfs_v3/4_ds_connect */
 	smp_rmb();
 	if (ds->ds_clp)
-		goto out_update_creds;
-
-	flavor = nfs4_ff_layout_choose_authflavor(mirror);
+		goto out;
 
 	/* FIXME: For now we assume the server sent only one version of NFS
 	 * to use for the DS.
@@ -394,7 +394,7 @@ nfs4_ff_layout_prepare_ds(struct pnfs_layout_segment *lseg, u32 ds_idx,
 			     dataserver_retrans,
 			     mirror->mirror_ds->ds_versions[0].version,
 			     mirror->mirror_ds->ds_versions[0].minor_version,
-			     flavor);
+			     RPC_AUTH_UNIX);
 
 	/* connect success, check rsize/wsize limit */
 	if (ds->ds_clp) {
@@ -410,20 +410,10 @@ nfs4_ff_layout_prepare_ds(struct pnfs_layout_segment *lseg, u32 ds_idx,
 					 mirror, lseg->pls_range.offset,
 					 lseg->pls_range.length, NFS4ERR_NXIO,
 					 OP_ILLEGAL, GFP_NOIO);
-		if (!fail_return) {
-			if (ff_layout_has_available_ds(lseg))
-				set_bit(NFS_LAYOUT_RETURN_REQUESTED,
-					&lseg->pls_layout->plh_flags);
-			else
-				pnfs_error_mark_layout_for_return(ino, lseg);
-		} else
+		if (fail_return || !ff_layout_has_available_ds(lseg))
 			pnfs_error_mark_layout_for_return(ino, lseg);
 		ds = NULL;
-		goto out;
 	}
-out_update_creds:
-	if (ff_layout_update_mirror_cred(mirror, ds))
-		ds = NULL;
 out:
 	return ds;
 }
@@ -433,16 +423,15 @@ ff_layout_get_ds_cred(struct pnfs_layout_segment *lseg, u32 ds_idx,
 		      struct rpc_cred *mdscred)
 {
 	struct nfs4_ff_layout_mirror *mirror = FF_LAYOUT_COMP(lseg, ds_idx);
-	struct rpc_cred *cred = ERR_PTR(-EINVAL);
-
-	if (!nfs4_ff_layout_prepare_ds(lseg, ds_idx, true))
-		goto out;
+	struct rpc_cred *cred;
 
-	if (mirror && mirror->cred)
-		cred = mirror->cred;
-	else
-		cred = mdscred;
-out:
+	if (mirror) {
+		cred = ff_layout_get_mirror_cred(mirror, lseg->pls_range.iomode);
+		if (!cred)
+			cred = get_rpccred(mdscred);
+	} else {
+		cred = get_rpccred(mdscred);
+	}
 	return cred;
 }
 
@@ -562,6 +551,18 @@ bool ff_layout_has_available_ds(struct pnfs_layout_segment *lseg)
 	return ff_rw_layout_has_available_ds(lseg);
 }
 
+bool ff_layout_avoid_mds_available_ds(struct pnfs_layout_segment *lseg)
+{
+	return ff_layout_no_fallback_to_mds(lseg) ||
+	       ff_layout_has_available_ds(lseg);
+}
+
+bool ff_layout_avoid_read_on_rw(struct pnfs_layout_segment *lseg)
+{
+	return lseg->pls_range.iomode == IOMODE_RW &&
+	       ff_layout_no_read_on_rw(lseg);
+}
+
 module_param(dataserver_retrans, uint, 0644);
 MODULE_PARM_DESC(dataserver_retrans, "The  number of times the NFSv4.1 client "
 			"retries a request before it attempts further "