nfs4: add NFSv4 LOOKUPP handlers

This will be needed in order to implement the get_parent export op
for nfsd.

Signed-off-by: Jeff Layton <jeff.layton@primarydata.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

5 files changed, 170 insertions, 1 deletions

diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index 01dcd4c8dc4f..e1a26c653e78 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -3805,6 +3805,54 @@ nfs4_proc_lookup_mountpoint(struct inode *dir, const struct qstr *name,
         return (client == NFS_CLIENT(dir)) ? rpc_clone_client(client) : client;
 }
 
+static int _nfs4_proc_lookupp(struct inode *inode,
+                struct nfs_fh *fhandle, struct nfs_fattr *fattr,
+                struct nfs4_label *label)
+{
+        struct rpc_clnt *clnt = NFS_CLIENT(inode);
+        struct nfs_server *server = NFS_SERVER(inode);
+        int                    status;
+        struct nfs4_lookupp_arg args = {
+                .bitmask = server->attr_bitmask,
+                .fh = NFS_FH(inode),
+        };
+        struct nfs4_lookupp_res res = {
+                .server = server,
+                .fattr = fattr,
+                .label = label,
+                .fh = fhandle,
+        };
+        struct rpc_message msg = {
+                .rpc_proc = &nfs4_procedures[NFSPROC4_CLNT_LOOKUPP],
+                .rpc_argp = &args,
+                .rpc_resp = &res,
+        };
+
+        args.bitmask = nfs4_bitmask(server, label);
+
+        nfs_fattr_init(fattr);
+
+        dprintk("NFS call  lookupp ino=0x%lx\n", inode->i_ino);
+        status = nfs4_call_sync(clnt, server, &msg, &args.seq_args,
+                                &res.seq_res, 0);
+        dprintk("NFS reply lookupp: %d\n", status);
+        return status;
+}
+
+static int nfs4_proc_lookupp(struct inode *inode, struct nfs_fh *fhandle,
+                             struct nfs_fattr *fattr, struct nfs4_label *label)
+{
+        struct nfs4_exception exception = { };
+        int err;
+        do {
+                err = _nfs4_proc_lookupp(inode, fhandle, fattr, label);
+                trace_nfs4_lookupp(inode, err);
+                err = nfs4_handle_exception(NFS_SERVER(inode), err,
+                                &exception);
+        } while (exception.retry);
+        return err;
+}
+
 static int _nfs4_proc_access(struct inode *inode, struct nfs_access_entry *entry)
 {
         struct nfs_server *server = NFS_SERVER(inode);
@@ -9314,6 +9362,7 @@ const struct nfs_rpc_ops nfs_v4_clientops = {
         .getattr        = nfs4_proc_getattr,
         .setattr        = nfs4_proc_setattr,
         .lookup         = nfs4_proc_lookup,
+        .lookupp        = nfs4_proc_lookupp,
         .access         = nfs4_proc_access,
         .readlink       = nfs4_proc_readlink,
         .create         = nfs4_proc_create,
diff --git a/fs/nfs/nfs4trace.h b/fs/nfs/nfs4trace.h
index 845d0eadefc9..be1da19c65d6 100644
--- a/fs/nfs/nfs4trace.h
+++ b/fs/nfs/nfs4trace.h
@@ -891,6 +891,35 @@ DEFINE_NFS4_LOOKUP_EVENT(nfs4_remove);
 DEFINE_NFS4_LOOKUP_EVENT(nfs4_get_fs_locations);
 DEFINE_NFS4_LOOKUP_EVENT(nfs4_secinfo);
 
+TRACE_EVENT(nfs4_lookupp,
+                TP_PROTO(
+                        const struct inode *inode,
+                        int error
+                ),
+
+                TP_ARGS(inode, error),
+
+                TP_STRUCT__entry(
+                        __field(dev_t, dev)
+                        __field(u64, ino)
+                        __field(int, error)
+                ),
+
+                TP_fast_assign(
+                        __entry->dev = inode->i_sb->s_dev;
+                        __entry->ino = NFS_FILEID(inode);
+                        __entry->error = error;
+                ),
+
+                TP_printk(
+                        "error=%d (%s) inode=%02x:%02x:%llu",
+                        __entry->error,
+                        show_nfsv4_errors(__entry->error),
+                        MAJOR(__entry->dev), MINOR(__entry->dev),
+                        (unsigned long long)__entry->ino
+                )
+);
+
 TRACE_EVENT(nfs4_rename,
                 TP_PROTO(
                         const struct inode *olddir,
diff --git a/fs/nfs/nfs4xdr.c b/fs/nfs/nfs4xdr.c
index 495d493d3a35..fa3eb361d4f8 100644
--- a/fs/nfs/nfs4xdr.c
+++ b/fs/nfs/nfs4xdr.c
@@ -159,6 +159,8 @@ static int nfs4_stat_to_errno(int);
                                 (op_decode_hdr_maxsz)
 #define encode_lookup_maxsz     (op_encode_hdr_maxsz + nfs4_name_maxsz)
 #define decode_lookup_maxsz     (op_decode_hdr_maxsz)
+#define encode_lookupp_maxsz    (op_encode_hdr_maxsz)
+#define decode_lookupp_maxsz    (op_decode_hdr_maxsz)
 #define encode_share_access_maxsz \
                                 (2)
 #define encode_createmode_maxsz (1 + encode_attrs_maxsz + encode_verifier_maxsz)
@@ -618,6 +620,18 @@ static int nfs4_stat_to_errno(int);
                                 decode_lookup_maxsz + \
                                 decode_getattr_maxsz + \
                                 decode_getfh_maxsz)
+#define NFS4_enc_lookupp_sz     (compound_encode_hdr_maxsz + \
+                                encode_sequence_maxsz + \
+                                encode_putfh_maxsz + \
+                                encode_lookupp_maxsz + \
+                                encode_getattr_maxsz + \
+                                encode_getfh_maxsz)
+#define NFS4_dec_lookupp_sz     (compound_decode_hdr_maxsz + \
+                                decode_sequence_maxsz + \
+                                decode_putfh_maxsz + \
+                                decode_lookupp_maxsz + \
+                                decode_getattr_maxsz + \
+                                decode_getfh_maxsz)
 #define NFS4_enc_lookup_root_sz (compound_encode_hdr_maxsz + \
                                 encode_sequence_maxsz + \
                                 encode_putrootfh_maxsz + \
@@ -1368,6 +1382,11 @@ static void encode_lookup(struct xdr_stream *xdr, const struct qstr *name, struc
         encode_string(xdr, name->len, name->name);
 }
 
+static void encode_lookupp(struct xdr_stream *xdr, struct compound_hdr *hdr)
+{
+        encode_op_hdr(xdr, OP_LOOKUPP, decode_lookupp_maxsz, hdr);
+}
+
 static void encode_share_access(struct xdr_stream *xdr, u32 share_access)
 {
         __be32 *p;
@@ -2123,6 +2142,26 @@ static void nfs4_xdr_enc_lookup(struct rpc_rqst *req, struct xdr_stream *xdr,
 }
 
 /*
+ * Encode LOOKUPP request
+ */
+static void nfs4_xdr_enc_lookupp(struct rpc_rqst *req, struct xdr_stream *xdr,
+                const void *data)
+{
+        const struct nfs4_lookupp_arg *args = data;
+        struct compound_hdr hdr = {
+                .minorversion = nfs4_xdr_minorversion(&args->seq_args),
+        };
+
+        encode_compound_hdr(xdr, req, &hdr);
+        encode_sequence(xdr, &args->seq_args, &hdr);
+        encode_putfh(xdr, args->fh, &hdr);
+        encode_lookupp(xdr, &hdr);
+        encode_getfh(xdr, &hdr);
+        encode_getfattr(xdr, args->bitmask, &hdr);
+        encode_nops(&hdr);
+}
+
+/*
  * Encode LOOKUP_ROOT request
  */
 static void nfs4_xdr_enc_lookup_root(struct rpc_rqst *req,
@@ -5058,6 +5097,11 @@ static int decode_lookup(struct xdr_stream *xdr)
         return decode_op_hdr(xdr, OP_LOOKUP);
 }
 
+static int decode_lookupp(struct xdr_stream *xdr)
+{
+        return decode_op_hdr(xdr, OP_LOOKUPP);
+}
+
 /* This is too sick! */
 static int decode_space_limit(struct xdr_stream *xdr,
                 unsigned long *pagemod_limit)
@@ -6238,6 +6282,36 @@ out:
 }
 
 /*
+ * Decode LOOKUPP response
+ */
+static int nfs4_xdr_dec_lookupp(struct rpc_rqst *rqstp, struct xdr_stream *xdr,
+                void *data)
+{
+        struct nfs4_lookupp_res *res = data;
+        struct compound_hdr hdr;
+        int status;
+
+        status = decode_compound_hdr(xdr, &hdr);
+        if (status)
+                goto out;
+        status = decode_sequence(xdr, &res->seq_res, rqstp);
+        if (status)
+                goto out;
+        status = decode_putfh(xdr);
+        if (status)
+                goto out;
+        status = decode_lookupp(xdr);
+        if (status)
+                goto out;
+        status = decode_getfh(xdr, res->fh);
+        if (status)
+                goto out;
+        status = decode_getfattr_label(xdr, res->fattr, res->label, res->server);
+out:
+        return status;
+}
+
+/*
  * Decode LOOKUP_ROOT response
  */
 static int nfs4_xdr_dec_lookup_root(struct rpc_rqst *rqstp,
@@ -7614,6 +7688,7 @@ const struct rpc_procinfo nfs4_procedures[] = {
         PROC(ACCESS,            enc_access,             dec_access),
         PROC(GETATTR,           enc_getattr,            dec_getattr),
         PROC(LOOKUP,            enc_lookup,             dec_lookup),
+        PROC(LOOKUPP,           enc_lookupp,            dec_lookupp),
         PROC(LOOKUP_ROOT,       enc_lookup_root,        dec_lookup_root),
         PROC(REMOVE,            enc_remove,             dec_remove),
         PROC(RENAME,            enc_rename,             dec_rename),
diff --git a/include/linux/nfs4.h b/include/linux/nfs4.h
index 1b1ca04820a3..47239c336688 100644
--- a/include/linux/nfs4.h
+++ b/include/linux/nfs4.h
@@ -479,6 +479,7 @@ enum {
         NFSPROC4_CLNT_ACCESS,
         NFSPROC4_CLNT_GETATTR,
         NFSPROC4_CLNT_LOOKUP,
+        NFSPROC4_CLNT_LOOKUPP,
         NFSPROC4_CLNT_LOOKUP_ROOT,
         NFSPROC4_CLNT_REMOVE,
         NFSPROC4_CLNT_RENAME,
diff --git a/include/linux/nfs_xdr.h b/include/linux/nfs_xdr.h
index 89093341f076..ca3bcc4ed4e5 100644
--- a/include/linux/nfs_xdr.h
+++ b/include/linux/nfs_xdr.h
@@ -1012,7 +1012,6 @@ struct nfs4_link_res {
         struct nfs_fattr *              dir_attr;
 };
 
-
 struct nfs4_lookup_arg {
         struct nfs4_sequence_args       seq_args;
         const struct nfs_fh *           dir_fh;
@@ -1028,6 +1027,20 @@ struct nfs4_lookup_res {
         struct nfs4_label               *label;
 };
 
+struct nfs4_lookupp_arg {
+        struct nfs4_sequence_args       seq_args;
+        const struct nfs_fh             *fh;
+        const u32                       *bitmask;
+};
+
+struct nfs4_lookupp_res {
+        struct nfs4_sequence_res        seq_res;
+        const struct nfs_server         *server;
+        struct nfs_fattr                *fattr;
+        struct nfs_fh                   *fh;
+        struct nfs4_label               *label;
+};
+
 struct nfs4_lookup_root_arg {
         struct nfs4_sequence_args       seq_args;
         const u32 *                     bitmask;
@@ -1569,6 +1582,8 @@ struct nfs_rpc_ops {
         int     (*lookup)  (struct inode *, const struct qstr *,
                             struct nfs_fh *, struct nfs_fattr *,
                             struct nfs4_label *);
+        int     (*lookupp) (struct inode *, struct nfs_fh *,
+                            struct nfs_fattr *, struct nfs4_label *);
         int     (*access)  (struct inode *, struct nfs_access_entry *);
         int     (*readlink)(struct inode *, struct page *, unsigned int,
                             unsigned int);