pnfs: GETDEVICELIST

The block driver uses GETDEVICELIST

Signed-off-by: Andy Adamson <andros@netapp.com>
[pass struct nfs_server * to getdevicelist]
[get machince creds for getdevicelist]
[fix getdevicelist decode sizing]
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: Benny Halevy <bhalevy@tonian.com>
Signed-off-by: Jim Rees <rees@umich.edu>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

3 files changed, 191 insertions, 0 deletions

diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index efa6ae822ca..af32d3df054 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -5834,6 +5834,54 @@ int nfs4_proc_layoutreturn(struct nfs4_layoutreturn *lrp)
 	return status;
 }
 
+/*
+ * Retrieve the list of Data Server devices from the MDS.
+ */
+static int _nfs4_getdevicelist(struct nfs_server *server,
+				    const struct nfs_fh *fh,
+				    struct pnfs_devicelist *devlist)
+{
+	struct nfs4_getdevicelist_args args = {
+		.fh = fh,
+		.layoutclass = server->pnfs_curr_ld->id,
+	};
+	struct nfs4_getdevicelist_res res = {
+		.devlist = devlist,
+	};
+	struct rpc_message msg = {
+		.rpc_proc = &nfs4_procedures[NFSPROC4_CLNT_GETDEVICELIST],
+		.rpc_argp = &args,
+		.rpc_resp = &res,
+	};
+	int status;
+
+	dprintk("--> %s\n", __func__);
+	status = nfs4_call_sync(server->client, server, &msg, &args.seq_args,
+				&res.seq_res, 0);
+	dprintk("<-- %s status=%d\n", __func__, status);
+	return status;
+}
+
+int nfs4_proc_getdevicelist(struct nfs_server *server,
+			    const struct nfs_fh *fh,
+			    struct pnfs_devicelist *devlist)
+{
+	struct nfs4_exception exception = { };
+	int err;
+
+	do {
+		err = nfs4_handle_exception(server,
+				_nfs4_getdevicelist(server, fh, devlist),
+				&exception);
+	} while (exception.retry);
+
+	dprintk("%s: err=%d, num_devs=%u\n", __func__,
+		err, devlist->num_devs);
+
+	return err;
+}
+EXPORT_SYMBOL_GPL(nfs4_proc_getdevicelist);
+
 static int
 _nfs4_proc_getdeviceinfo(struct nfs_server *server, struct pnfs_device *pdev)
 {
diff --git a/fs/nfs/nfs4xdr.c b/fs/nfs/nfs4xdr.c
index b851b560a6f..5f769f8d05b 100644
--- a/fs/nfs/nfs4xdr.c
+++ b/fs/nfs/nfs4xdr.c
@@ -314,6 +314,17 @@ static int nfs4_stat_to_errno(int);
 				XDR_QUADLEN(NFS4_MAX_SESSIONID_LEN) + 5)
 #define encode_reclaim_complete_maxsz	(op_encode_hdr_maxsz + 4)
 #define decode_reclaim_complete_maxsz	(op_decode_hdr_maxsz + 4)
+#define encode_getdevicelist_maxsz (op_encode_hdr_maxsz + 4 + \
+				encode_verifier_maxsz)
+#define decode_getdevicelist_maxsz (op_decode_hdr_maxsz + \
+				2 /* nfs_cookie4 gdlr_cookie */ + \
+				decode_verifier_maxsz \
+				  /* verifier4 gdlr_verifier */ + \
+				1 /* gdlr_deviceid_list count */ + \
+				XDR_QUADLEN(NFS4_PNFS_GETDEVLIST_MAXNUM * \
+					    NFS4_DEVICEID4_SIZE) \
+				  /* gdlr_deviceid_list */ + \
+				1 /* bool gdlr_eof */)
 #define encode_getdeviceinfo_maxsz (op_encode_hdr_maxsz + 4 + \
 				XDR_QUADLEN(NFS4_DEVICEID4_SIZE))
 #define decode_getdeviceinfo_maxsz (op_decode_hdr_maxsz + \
@@ -748,6 +759,14 @@ static int nfs4_stat_to_errno(int);
 #define NFS4_dec_reclaim_complete_sz	(compound_decode_hdr_maxsz + \
 					 decode_sequence_maxsz + \
 					 decode_reclaim_complete_maxsz)
+#define NFS4_enc_getdevicelist_sz (compound_encode_hdr_maxsz + \
+				encode_sequence_maxsz + \
+				encode_putfh_maxsz + \
+				encode_getdevicelist_maxsz)
+#define NFS4_dec_getdevicelist_sz (compound_decode_hdr_maxsz + \
+				decode_sequence_maxsz + \
+				decode_putfh_maxsz + \
+				decode_getdevicelist_maxsz)
 #define NFS4_enc_getdeviceinfo_sz (compound_encode_hdr_maxsz +    \
 				encode_sequence_maxsz +\
 				encode_getdeviceinfo_maxsz)
@@ -1855,6 +1874,26 @@ static void encode_sequence(struct xdr_stream *xdr,
 
 #ifdef CONFIG_NFS_V4_1
 static void
+encode_getdevicelist(struct xdr_stream *xdr,
+		     const struct nfs4_getdevicelist_args *args,
+		     struct compound_hdr *hdr)
+{
+	__be32 *p;
+	nfs4_verifier dummy = {
+		.data = "dummmmmy",
+	};
+
+	p = reserve_space(xdr, 20);
+	*p++ = cpu_to_be32(OP_GETDEVICELIST);
+	*p++ = cpu_to_be32(args->layoutclass);
+	*p++ = cpu_to_be32(NFS4_PNFS_GETDEVLIST_MAXNUM);
+	xdr_encode_hyper(p, 0ULL);                          /* cookie */
+	encode_nfs4_verifier(xdr, &dummy);
+	hdr->nops++;
+	hdr->replen += decode_getdevicelist_maxsz;
+}
+
+static void
 encode_getdeviceinfo(struct xdr_stream *xdr,
 		     const struct nfs4_getdeviceinfo_args *args,
 		     struct compound_hdr *hdr)
@@ -2775,6 +2814,24 @@ static void nfs4_xdr_enc_reclaim_complete(struct rpc_rqst *req,
 }
 
 /*
+ * Encode GETDEVICELIST request
+ */
+static void nfs4_xdr_enc_getdevicelist(struct rpc_rqst *req,
+				       struct xdr_stream *xdr,
+				       struct nfs4_getdevicelist_args *args)
+{
+	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_getdevicelist(xdr, args, &hdr);
+	encode_nops(&hdr);
+}
+
+/*
  * Encode GETDEVICEINFO request
  */
 static void nfs4_xdr_enc_getdeviceinfo(struct rpc_rqst *req,
@@ -5268,6 +5325,53 @@ out_overflow:
 }
 
 #if defined(CONFIG_NFS_V4_1)
+/*
+ * TODO: Need to handle case when EOF != true;
+ */
+static int decode_getdevicelist(struct xdr_stream *xdr,
+				struct pnfs_devicelist *res)
+{
+	__be32 *p;
+	int status, i;
+	struct nfs_writeverf verftemp;
+
+	status = decode_op_hdr(xdr, OP_GETDEVICELIST);
+	if (status)
+		return status;
+
+	p = xdr_inline_decode(xdr, 8 + 8 + 4);
+	if (unlikely(!p))
+		goto out_overflow;
+
+	/* TODO: Skip cookie for now */
+	p += 2;
+
+	/* Read verifier */
+	p = xdr_decode_opaque_fixed(p, verftemp.verifier, 8);
+
+	res->num_devs = be32_to_cpup(p);
+
+	dprintk("%s: num_dev %d\n", __func__, res->num_devs);
+
+	if (res->num_devs > NFS4_PNFS_GETDEVLIST_MAXNUM) {
+		printk(KERN_ERR "%s too many result dev_num %u\n",
+				__func__, res->num_devs);
+		return -EIO;
+	}
+
+	p = xdr_inline_decode(xdr,
+			      res->num_devs * NFS4_DEVICEID4_SIZE + 4);
+	if (unlikely(!p))
+		goto out_overflow;
+	for (i = 0; i < res->num_devs; i++)
+		p = xdr_decode_opaque_fixed(p, res->dev_id[i].data,
+					    NFS4_DEVICEID4_SIZE);
+	res->eof = be32_to_cpup(p);
+	return 0;
+out_overflow:
+	print_overflow_msg(__func__, xdr);
+	return -EIO;
+}
 
 static int decode_getdeviceinfo(struct xdr_stream *xdr,
 				struct pnfs_device *pdev)
@@ -6542,6 +6646,32 @@ static int nfs4_xdr_dec_reclaim_complete(struct rpc_rqst *rqstp,
 }
 
 /*
+ * Decode GETDEVICELIST response
+ */
+static int nfs4_xdr_dec_getdevicelist(struct rpc_rqst *rqstp,
+				      struct xdr_stream *xdr,
+				      struct nfs4_getdevicelist_res *res)
+{
+	struct compound_hdr hdr;
+	int status;
+
+	dprintk("encoding getdevicelist!\n");
+
+	status = decode_compound_hdr(xdr, &hdr);
+	if (status != 0)
+		goto out;
+	status = decode_sequence(xdr, &res->seq_res, rqstp);
+	if (status != 0)
+		goto out;
+	status = decode_putfh(xdr);
+	if (status != 0)
+		goto out;
+	status = decode_getdevicelist(xdr, res->devlist);
+out:
+	return status;
+}
+
+/*
  * Decode GETDEVINFO response
  */
 static int nfs4_xdr_dec_getdeviceinfo(struct rpc_rqst *rqstp,
@@ -6908,6 +7038,7 @@ struct rpc_procinfo	nfs4_procedures[] = {
 	PROC(SECINFO_NO_NAME,	enc_secinfo_no_name,	dec_secinfo_no_name),
 	PROC(TEST_STATEID,	enc_test_stateid,	dec_test_stateid),
 	PROC(FREE_STATEID,	enc_free_stateid,	dec_free_stateid),
+	PROC(GETDEVICELIST,	enc_getdevicelist,	dec_getdevicelist),
 #endif /* CONFIG_NFS_V4_1 */
 };
 
diff --git a/fs/nfs/pnfs.h b/fs/nfs/pnfs.h
index b94f874886c..7074394944a 100644
--- a/fs/nfs/pnfs.h
+++ b/fs/nfs/pnfs.h
@@ -135,14 +135,26 @@ struct pnfs_device {
 	unsigned int  layout_type;
 	unsigned int  mincount;
 	struct page **pages;
+	void          *area;
 	unsigned int  pgbase;
 	unsigned int  pglen;
 };
 
+#define NFS4_PNFS_GETDEVLIST_MAXNUM 16
+
+struct pnfs_devicelist {
+	unsigned int		eof;
+	unsigned int		num_devs;
+	struct nfs4_deviceid	dev_id[NFS4_PNFS_GETDEVLIST_MAXNUM];
+};
+
 extern int pnfs_register_layoutdriver(struct pnfs_layoutdriver_type *);
 extern void pnfs_unregister_layoutdriver(struct pnfs_layoutdriver_type *);
 
 /* nfs4proc.c */
+extern int nfs4_proc_getdevicelist(struct nfs_server *server,
+				   const struct nfs_fh *fh,
+				   struct pnfs_devicelist *devlist);
 extern int nfs4_proc_getdeviceinfo(struct nfs_server *server,
 				   struct pnfs_device *dev);
 extern int nfs4_proc_layoutget(struct nfs4_layoutget *lgp);