NFSv4: convert fs-locations-components to conform to RFC3530

Use component4-style formats for decoding list of servers and pathnames in
fs_locations.

Signed-off-by: Manoj Naik <manoj@almaden.ibm.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

4 files changed, 94 insertions, 22 deletions

diff --git a/fs/nfs/nfs4_fs.h b/fs/nfs/nfs4_fs.h
index 5b7651171215..22a5f838ea58 100644
--- a/fs/nfs/nfs4_fs.h
+++ b/fs/nfs/nfs4_fs.h
@@ -219,7 +219,7 @@ extern struct dentry *nfs4_atomic_open(struct inode *, struct dentry *, struct n
 extern int nfs4_open_revalidate(struct inode *, struct dentry *, int, struct nameidata *);
 extern int nfs4_server_capabilities(struct nfs_server *server, struct nfs_fh *fhandle);
 extern int nfs4_proc_fs_locations(struct inode *dir, struct dentry *dentry,
-                struct nfs_fs_locations *fs_locations, struct page *page);
+                struct nfs4_fs_locations *fs_locations, struct page *page);
 
 extern struct nfs4_state_recovery_ops nfs4_reboot_recovery_ops;
 extern struct nfs4_state_recovery_ops nfs4_network_partition_recovery_ops;
diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index 768514dc0c4c..043223a0eda6 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -3571,7 +3571,7 @@ ssize_t nfs4_listxattr(struct dentry *dentry, char *buf, size_t buflen)
 }
 
 int nfs4_proc_fs_locations(struct inode *dir, struct dentry *dentry,
-                struct nfs_fs_locations *fs_locations, struct page *page)
+                struct nfs4_fs_locations *fs_locations, struct page *page)
 {
         struct nfs_server *server = NFS_SERVER(dir);
         u32 bitmask[2] = {
@@ -3587,7 +3587,7 @@ int nfs4_proc_fs_locations(struct inode *dir, struct dentry *dentry,
         struct rpc_message msg = {
                 .rpc_proc = &nfs4_procedures[NFSPROC4_CLNT_FS_LOCATIONS],
                 .rpc_argp = &args,
-                .rpc_resp = &fs_locations,
+                .rpc_resp = fs_locations,
         };
         int status;
 
diff --git a/fs/nfs/nfs4xdr.c b/fs/nfs/nfs4xdr.c
index 7add3137b6b6..f6a1ea7df374 100644
--- a/fs/nfs/nfs4xdr.c
+++ b/fs/nfs/nfs4xdr.c
@@ -2377,7 +2377,43 @@ static int decode_attr_files_total(struct xdr_stream *xdr, uint32_t *bitmap, uin
         return status;
 }
 
-static int decode_attr_fs_locations(struct xdr_stream *xdr, uint32_t *bitmap, struct nfs_fs_locations *res)
+static int decode_pathname(struct xdr_stream *xdr, struct nfs4_pathname *path)
+{
+        int n;
+        uint32_t *p;
+        int status = 0;
+
+        READ_BUF(4);
+        READ32(n);
+        if (n <= 0)
+                goto out_eio;
+        dprintk("path ");
+        path->ncomponents = 0;
+        while (path->ncomponents < n) {
+                struct nfs4_string *component = &path->components[path->ncomponents];
+                status = decode_opaque_inline(xdr, &component->len, &component->data);
+                if (unlikely(status != 0))
+                        goto out_eio;
+                if (path->ncomponents != n)
+                        dprintk("/");
+                dprintk("%s", component->data);
+                if (path->ncomponents < NFS4_PATHNAME_MAXCOMPONENTS)
+                        path->ncomponents++;
+                else {
+                        dprintk("cannot parse %d components in path\n", n);
+                        goto out_eio;
+                }
+        }
+out:
+        dprintk("\n");
+        return status;
+out_eio:
+        dprintk(" status %d", status);
+        status = -EIO;
+        goto out;
+}
+
+static int decode_attr_fs_locations(struct xdr_stream *xdr, uint32_t *bitmap, struct nfs4_fs_locations *res)
 {
         int n;
         uint32_t *p;
@@ -2388,7 +2424,8 @@ static int decode_attr_fs_locations(struct xdr_stream *xdr, uint32_t *bitmap, st
         status = 0;
         if (unlikely(!(bitmap[0] & FATTR4_WORD0_FS_LOCATIONS)))
                 goto out;
-        status = decode_opaque_inline(xdr, &res->fs_pathlen, &res->fs_path);
+        dprintk("%s: fsroot ", __FUNCTION__);
+        status = decode_pathname(xdr, &res->fs_path);
         if (unlikely(status != 0))
                 goto out;
         READ_BUF(4);
@@ -2397,15 +2434,40 @@ static int decode_attr_fs_locations(struct xdr_stream *xdr, uint32_t *bitmap, st
                 goto out_eio;
         res->nlocations = 0;
         while (res->nlocations < n) {
-                struct nfs_fs_location *loc = &res->locations[res->nlocations];
+                int m;
+                struct nfs4_fs_location *loc = &res->locations[res->nlocations];
 
-                status = decode_opaque_inline(xdr, &loc->serverlen, &loc->server);
-                if (unlikely(status != 0))
+                READ_BUF(4);
+                READ32(m);
+                if (m <= 0)
                         goto out_eio;
-                status = decode_opaque_inline(xdr, &loc->rootpathlen, &loc->rootpath);
+
+                loc->nservers = 0;
+                dprintk("%s: servers ", __FUNCTION__);
+                while (loc->nservers < m) {
+                        struct nfs4_string *server = &loc->servers[loc->nservers];
+                        status = decode_opaque_inline(xdr, &server->len, &server->data);
+                        if (unlikely(status != 0))
+                                goto out_eio;
+                        dprintk("%s ", server->data);
+                        if (loc->nservers < NFS4_FS_LOCATION_MAXSERVERS)
+                                loc->nservers++;
+                        else {
+                                int i;
+                                dprintk("%s: using first %d of %d servers returned for location %d\n", __FUNCTION__, NFS4_FS_LOCATION_MAXSERVERS, m, res->nlocations);
+                                for (i = loc->nservers; i < m; i++) {
+                                        int len;
+                                        char *data;
+                                        status = decode_opaque_inline(xdr, &len, &data);
+                                        if (unlikely(status != 0))
+                                                goto out_eio;
+                                }
+                        }
+                }
+                status = decode_pathname(xdr, &loc->rootpath);
                 if (unlikely(status != 0))
                         goto out_eio;
-                if (res->nlocations < NFS_FS_LOCATIONS_MAXENTRIES)
+                if (res->nlocations < NFS4_FS_LOCATIONS_MAXENTRIES)
                         res->nlocations++;
         }
 out:
@@ -2948,7 +3010,7 @@ static int decode_getfattr(struct xdr_stream *xdr, struct nfs_fattr *fattr, cons
         if ((status = decode_attr_fileid(xdr, bitmap, &fattr->fileid)) != 0)
                 goto xdr_error;
         if ((status = decode_attr_fs_locations(xdr, bitmap, container_of(fattr,
-                                                struct nfs_fs_locations,
+                                                struct nfs4_fs_locations,
                                                 fattr))) != 0)
                 goto xdr_error;
         if ((status = decode_attr_mode(xdr, bitmap, &fattr->mode)) != 0)
@@ -4297,7 +4359,7 @@ out:
 /*
  * FS_LOCATIONS request
  */
-static int nfs4_xdr_dec_fs_locations(struct rpc_rqst *req, uint32_t *p, struct nfs_fs_locations *res)
+static int nfs4_xdr_dec_fs_locations(struct rpc_rqst *req, uint32_t *p, struct nfs4_fs_locations *res)
 {
         struct xdr_stream xdr;
         struct compound_hdr hdr;
diff --git a/include/linux/nfs_xdr.h b/include/linux/nfs_xdr.h
index 15a20b815302..d6eea8348728 100644
--- a/include/linux/nfs_xdr.h
+++ b/include/linux/nfs_xdr.h
@@ -679,21 +679,31 @@ struct nfs4_server_caps_res {
         u32                             has_symlinks;
 };
 
-struct nfs_fs_location {
-        unsigned int serverlen;
-        char * server;
-        unsigned int rootpathlen;
-        char * rootpath;
+struct nfs4_string {
+        unsigned int len;
+        char *data;
 };
 
-#define NFS_FS_LOCATIONS_MAXENTRIES 10
-struct nfs_fs_locations {
+#define NFS4_PATHNAME_MAXCOMPONENTS 512
+struct nfs4_pathname {
+        unsigned int ncomponents;
+        struct nfs4_string components[NFS4_PATHNAME_MAXCOMPONENTS];
+};
+
+#define NFS4_FS_LOCATION_MAXSERVERS 10
+struct nfs4_fs_location {
+        unsigned int nservers;
+        struct nfs4_string servers[NFS4_FS_LOCATION_MAXSERVERS];
+        struct nfs4_pathname rootpath;
+};
+
+#define NFS4_FS_LOCATIONS_MAXENTRIES 10
+struct nfs4_fs_locations {
         struct nfs_fattr fattr;
         const struct nfs_server *server;
-        unsigned int fs_pathlen;
-        char * fs_path;
+        struct nfs4_pathname fs_path;
         int nlocations;
-        struct nfs_fs_location locations[NFS_FS_LOCATIONS_MAXENTRIES];
+        struct nfs4_fs_location locations[NFS4_FS_LOCATIONS_MAXENTRIES];
 };
 
 struct nfs4_fs_locations_arg {