[pnfs] [PATCH 28/73] pnfsd: support layout_type attribute for file layout

[andros at netapp.com]

From: Benny Halevy <bhalevy at panasas.com>

Provide for getting the (read-only) layout_type attribute

[extraced from pnfsd: Initial pNFS server implementation.]
Signed-off-by: Benny Halevy <bhalevy at panasas.com>
[pnfsd: Add super block to layout_type()]
Signed-off-by: Marc Eshel <eshel at almaden.ibm.com>
Signed-off-by: Benny Halevy <bhalevy at panasas.com>
[pnfsd: convert generic code to use new pnfs api]
Signed-off-by: Benny Halevy <bhalevy at panasas.com>

Remove the use of struct pnfs_export_operations.
Signed-off-by: Andy Adamson <andros at netapp.com>
Signed-off-by: Benny Halevy <bhalevy at panasas.com>
---
 fs/nfsd/nfs4xdr.c         |   23 +++++++++++++++++++++++
 include/linux/nfsd/nfsd.h |    5 +++++
 2 files changed, 28 insertions(+), 0 deletions(-)

diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c
index 4617e14..75c9dff 100644
--- a/fs/nfsd/nfs4xdr.c
+++ b/fs/nfsd/nfs4xdr.c
@@ -2318,6 +2318,29 @@ out_acl:
 		}
 		WRITE64(stat.ino);
 	}
+#if defined(CONFIG_PNFSD)
+	if (bmval1 & FATTR4_WORD1_FS_LAYOUT_TYPES) {
+		int type = 0;
+
+	/* Query the underlying filesystem for supported pNFS layout types.
+	 * Currently, we only support one layout type per file system.
+	 * The export_ops->layout_type() returns the pnfs_layouttype4.
+	 */
+		buflen -= 4;
+		if (buflen < 0)		/* length */
+			goto out_resource;
+
+		if (exp->ex_pnfs == 1)
+			type = LAYOUT_NFSV4_FILES;
+		if (type) {
+			if ((buflen -= 4) < 0)	/* type */
+				goto out_resource;
+			WRITE32(1); 	/* length */
+			WRITE32(type);  /* type */
+		} else
+			WRITE32(0);  /* length */
+	}
+#endif /* CONFIG_PNFSD */
 	if (bmval2 & FATTR4_WORD2_SUPPATTR_EXCLCREAT) {
 		WRITE32(3);
 		WRITE32(NFSD_SUPPATTR_EXCLCREAT_WORD0);
diff --git a/include/linux/nfsd/nfsd.h b/include/linux/nfsd/nfsd.h
index 2812ed5..bb283fb 100644
--- a/include/linux/nfsd/nfsd.h
+++ b/include/linux/nfsd/nfsd.h
@@ -371,8 +371,13 @@ extern struct timeval	nfssvc_boot;
 #define NFSD4_1_SUPPORTED_ATTRS_WORD0 \
 	NFSD4_SUPPORTED_ATTRS_WORD0
 
+#if defined(CONFIG_PNFSD)
+#define NFSD4_1_SUPPORTED_ATTRS_WORD1 \
+	(NFSD4_SUPPORTED_ATTRS_WORD1 | FATTR4_WORD1_FS_LAYOUT_TYPES)
+#else /* CONFIG_PNFSD */
 #define NFSD4_1_SUPPORTED_ATTRS_WORD1 \
 	NFSD4_SUPPORTED_ATTRS_WORD1
+#endif /* CONFIG_PNFSD */
 
 #define NFSD4_1_SUPPORTED_ATTRS_WORD2 \
 	(NFSD4_SUPPORTED_ATTRS_WORD2 | FATTR4_WORD2_SUPPATTR_EXCLCREAT)
-- 
1.5.4.3