1/*
  2 * Copyright (c) 2016 Tom Haynes <loghyr@primarydata.com>
  3 *
  4 * The following implements a super-simple flex-file server
  5 * where the NFSv4.1 mds is also the ds. And the storage is
  6 * the same. I.e., writing to the mds via a NFSv4.1 WRITE
  7 * goes to the same location as the NFSv3 WRITE.
  8 */
  9#include <linux/slab.h>
 10
 11#include <linux/nfsd/debug.h>
 12
 13#include <linux/sunrpc/addr.h>
 14
 15#include "flexfilelayoutxdr.h"
 16#include "pnfs.h"
 17
 18#define NFSDDBG_FACILITY	NFSDDBG_PNFS
 19
 20static __be32
 21nfsd4_ff_proc_layoutget(struct inode *inode, const struct svc_fh *fhp,
 22		struct nfsd4_layoutget *args)
 23{
 24	struct nfsd4_layout_seg *seg = &args->lg_seg;
 25	u32 device_generation = 0;
 26	int error;
 27	uid_t u;
 28
 29	struct pnfs_ff_layout *fl;
 30
 31	/*
 32	 * The super simple flex file server has 1 mirror, 1 data server,
 33	 * and 1 file handle. So instead of 4 allocs, do 1 for now.
 34	 * Zero it out for the stateid - don't want junk in there!
 35	 */
 36	error = -ENOMEM;
 37	fl = kzalloc(sizeof(*fl), GFP_KERNEL);
 38	if (!fl)
 39		goto out_error;
 40	args->lg_content = fl;
 41
 42	/*
 43	 * Avoid layout commit, try to force the I/O to the DS,
 44	 * and for fun, cause all IOMODE_RW layout segments to
 45	 * effectively be WRITE only.
 46	 */
 47	fl->flags = FF_FLAGS_NO_LAYOUTCOMMIT | FF_FLAGS_NO_IO_THRU_MDS |
 48		    FF_FLAGS_NO_READ_IO;
 49
 50	/* Do not allow a IOMODE_READ segment to have write pemissions */
 51	if (seg->iomode == IOMODE_READ) {
 52		u = from_kuid(&init_user_ns, inode->i_uid) + 1;
 53		fl->uid = make_kuid(&init_user_ns, u);
 54	} else
 55		fl->uid = inode->i_uid;
 56	fl->gid = inode->i_gid;
 57
 58	error = nfsd4_set_deviceid(&fl->deviceid, fhp, device_generation);
 59	if (error)
 60		goto out_error;
 61
 62	fl->fh.size = fhp->fh_handle.fh_size;
 63	memcpy(fl->fh.data, &fhp->fh_handle.fh_base, fl->fh.size);
 64
 65	/* Give whole file layout segments */
 66	seg->offset = 0;
 67	seg->length = NFS4_MAX_UINT64;
 68
 69	dprintk("GET: 0x%llx:0x%llx %d\n", seg->offset, seg->length,
 70		seg->iomode);
 71	return 0;
 72
 73out_error:
 74	seg->length = 0;
 75	return nfserrno(error);
 76}
 77
 78static __be32
 79nfsd4_ff_proc_getdeviceinfo(struct super_block *sb, struct svc_rqst *rqstp,
 80		struct nfs4_client *clp, struct nfsd4_getdeviceinfo *gdp)
 81{
 82	struct pnfs_ff_device_addr *da;
 83
 84	u16 port;
 85	char addr[INET6_ADDRSTRLEN];
 86
 87	da = kzalloc(sizeof(struct pnfs_ff_device_addr), GFP_KERNEL);
 88	if (!da)
 89		return nfserrno(-ENOMEM);
 90
 91	gdp->gd_device = da;
 92
 93	da->version = 3;
 94	da->minor_version = 0;
 95
 96	da->rsize = svc_max_payload(rqstp);
 97	da->wsize = da->rsize;
 98
 99	rpc_ntop((struct sockaddr *)&rqstp->rq_daddr,
100		 addr, INET6_ADDRSTRLEN);
101	if (rqstp->rq_daddr.ss_family == AF_INET) {
102		struct sockaddr_in *sin;
103
104		sin = (struct sockaddr_in *)&rqstp->rq_daddr;
105		port = ntohs(sin->sin_port);
106		snprintf(da->netaddr.netid, FF_NETID_LEN + 1, "tcp");
107		da->netaddr.netid_len = 3;
108	} else {
109		struct sockaddr_in6 *sin6;
110
111		sin6 = (struct sockaddr_in6 *)&rqstp->rq_daddr;
112		port = ntohs(sin6->sin6_port);
113		snprintf(da->netaddr.netid, FF_NETID_LEN + 1, "tcp6");
114		da->netaddr.netid_len = 4;
115	}
116
117	da->netaddr.addr_len =
118		snprintf(da->netaddr.addr, FF_ADDR_LEN + 1,
119			 "%s.%hhu.%hhu", addr, port >> 8, port & 0xff);
120
121	da->tightly_coupled = false;
122
123	return 0;
124}
125
126const struct nfsd4_layout_ops ff_layout_ops = {
127	.notify_types		=
128			NOTIFY_DEVICEID4_DELETE | NOTIFY_DEVICEID4_CHANGE,
129	.disable_recalls	= true,
130	.proc_getdeviceinfo	= nfsd4_ff_proc_getdeviceinfo,
131	.encode_getdeviceinfo	= nfsd4_ff_encode_getdeviceinfo,
132	.proc_layoutget		= nfsd4_ff_proc_layoutget,
133	.encode_layoutget	= nfsd4_ff_encode_layoutget,
134};