aboutsummaryrefslogtreecommitdiffstats
path: root/fs/nfs/callback_proc.c
blob: 61b85306bb251d30cf0ae3270ab23d84d2621cff (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
/*
 * linux/fs/nfs/callback_proc.c
 *
 * Copyright (C) 2004 Trond Myklebust
 *
 * NFSv4 callback procedures
 */
#include <linux/nfs4.h>
#include <linux/nfs_fs.h>
#include "nfs4_fs.h"
#include "callback.h"
#include "delegation.h"
#include "internal.h"

#ifdef NFS_DEBUG
#define NFSDBG_FACILITY NFSDBG_CALLBACK
#endif
 
__be32 nfs4_callback_getattr(struct cb_getattrargs *args, struct cb_getattrres *res)
{
	struct nfs_client *clp;
	struct nfs_delegation *delegation;
	struct nfs_inode *nfsi;
	struct inode *inode;

	res->bitmap[0] = res->bitmap[1] = 0;
	res->status = htonl(NFS4ERR_BADHANDLE);
	clp = nfs_find_client(args->addr, 4);
	if (clp == NULL)
		goto out;

	dprintk("NFS: GETATTR callback request from %s\n",
		rpc_peeraddr2str(clp->cl_rpcclient, RPC_DISPLAY_ADDR));

	inode = nfs_delegation_find_inode(clp, &args->fh);
	if (inode == NULL)
		goto out_putclient;
	nfsi = NFS_I(inode);
	down_read(&nfsi->rwsem);
	delegation = nfsi->delegation;
	if (delegation == NULL || (delegation->type & FMODE_WRITE) == 0)
		goto out_iput;
	res->size = i_size_read(inode);
	res->change_attr = delegation->change_attr;
	if (nfsi->npages != 0)
		res->change_attr++;
	res->ctime = inode->i_ctime;
	res->mtime = inode->i_mtime;
	res->bitmap[0] = (FATTR4_WORD0_CHANGE|FATTR4_WORD0_SIZE) &
		args->bitmap[0];
	res->bitmap[1] = (FATTR4_WORD1_TIME_METADATA|FATTR4_WORD1_TIME_MODIFY) &
		args->bitmap[1];
	res->status = 0;
out_iput:
	up_read(&nfsi->rwsem);
	iput(inode);
out_putclient:
	nfs_put_client(clp);
out:
	dprintk("%s: exit with status = %d\n", __func__, ntohl(res->status));
	return res->status;
}

__be32 nfs4_callback_recall(struct cb_recallargs *args, void *dummy)
{
	struct nfs_client *clp;
	struct inode *inode;
	__be32 res;
	
	res = htonl(NFS4ERR_BADHANDLE);
	clp = nfs_find_client(args->addr, 4);
	if (clp == NULL)
		goto out;

	dprintk("NFS: RECALL callback request from %s\n",
		rpc_peeraddr2str(clp->cl_rpcclient, RPC_DISPLAY_ADDR));

	do {
		struct nfs_client *prev = clp;

		inode = nfs_delegation_find_inode(clp, &args->fh);
		if (inode != NULL) {
			/* Set up a helper thread to actually return the delegation */
			switch(nfs_async_inode_return_delegation(inode, &args->stateid)) {
				case 0:
					res = 0;
					break;
				case -ENOENT:
					if (res != 0)
						res = htonl(NFS4ERR_BAD_STATEID);
					break;
				default:
					res = htonl(NFS4ERR_RESOURCE);
			}
			iput(inode);
		}
		clp = nfs_find_client_next(prev);
		nfs_put_client(prev);
	} while (clp != NULL);
out:
	dprintk("%s: exit with status = %d\n", __func__, ntohl(res));
	return res;
}

#if defined(CONFIG_NFS_V4_1)

/*
 * Validate the sequenceID sent by the server.
 * Return success if the sequenceID is one more than what we last saw on
 * this slot, accounting for wraparound.  Increments the slot's sequence.
 *
 * We don't yet implement a duplicate request cache, so at this time
 * we will log replays, and process them as if we had not seen them before,
 * but we don't bump the sequence in the slot.  Not too worried about it,
 * since we only currently implement idempotent callbacks anyway.
 *
 * We have a single slot backchannel at this time, so we don't bother
 * checking the used_slots bit array on the table.  The lower layer guarantees
 * a single outstanding callback request at a time.
 */
static int
validate_seqid(struct nfs4_slot_table *tbl, u32 slotid, u32 seqid)
{
	struct nfs4_slot *slot;

	dprintk("%s enter. slotid %d seqid %d\n",
		__func__, slotid, seqid);

	if (slotid > NFS41_BC_MAX_CALLBACKS)
		return htonl(NFS4ERR_BADSLOT);

	slot = tbl->slots + slotid;
	dprintk("%s slot table seqid: %d\n", __func__, slot->seq_nr);

	/* Normal */
	if (likely(seqid == slot->seq_nr + 1)) {
		slot->seq_nr++;
		return htonl(NFS4_OK);
	}

	/* Replay */
	if (seqid == slot->seq_nr) {
		dprintk("%s seqid %d is a replay - no DRC available\n",
			__func__, seqid);
		return htonl(NFS4_OK);
	}

	/* Wraparound */
	if (seqid == 1 && (slot->seq_nr + 1) == 0) {
		slot->seq_nr = 1;
		return htonl(NFS4_OK);
	}

	/* Misordered request */
	return htonl(NFS4ERR_SEQ_MISORDERED);
}

/*
 * Returns a pointer to a held 'struct nfs_client' that matches the server's
 * address, major version number, and session ID.  It is the caller's
 * responsibility to release the returned reference.
 *
 * Returns NULL if there are no connections with sessions, or if no session
 * matches the one of interest.
 */
 static struct nfs_client *find_client_with_session(
	const struct sockaddr *addr, u32 nfsversion,
	struct nfs4_sessionid *sessionid)
{
	struct nfs_client *clp;

	clp = nfs_find_client(addr, 4);
	if (clp == NULL)
		return NULL;

	do {
		struct nfs_client *prev = clp;

		if (clp->cl_session != NULL) {
			if (memcmp(clp->cl_session->sess_id.data,
					sessionid->data,
					NFS4_MAX_SESSIONID_LEN) == 0) {
				/* Returns a held reference to clp */
				return clp;
			}
		}
		clp = nfs_find_client_next(prev);
		nfs_put_client(prev);
	} while (clp != NULL);

	return NULL;
}

/* FIXME: referring calls should be processed */
unsigned nfs4_callback_sequence(struct cb_sequenceargs *args,
				struct cb_sequenceres *res)
{
	struct nfs_client *clp;
	int i, status;

	for (i = 0; i < args->csa_nrclists; i++)
		kfree(args->csa_rclists[i].rcl_refcalls);
	kfree(args->csa_rclists);

	status = htonl(NFS4ERR_BADSESSION);
	clp = find_client_with_session(args->csa_addr, 4, &args->csa_sessionid);
	if (clp == NULL)
		goto out;

	status = validate_seqid(&clp->cl_session->bc_slot_table,
				args->csa_slotid, args->csa_sequenceid);
	if (status)
		goto out_putclient;

	memcpy(&res->csr_sessionid, &args->csa_sessionid,
	       sizeof(res->csr_sessionid));
	res->csr_sequenceid = args->csa_sequenceid;
	res->csr_slotid = args->csa_slotid;
	res->csr_highestslotid = NFS41_BC_MAX_CALLBACKS - 1;
	res->csr_target_highestslotid = NFS41_BC_MAX_CALLBACKS - 1;

out_putclient:
	nfs_put_client(clp);
out:
	dprintk("%s: exit with status = %d\n", __func__, ntohl(status));
	res->csr_status = status;
	return res->csr_status;
}

unsigned nfs4_callback_recallany(struct cb_recallanyargs *args, void *dummy)
{
	struct nfs_client *clp;
	int status;
	fmode_t flags = 0;

	status = htonl(NFS4ERR_OP_NOT_IN_SESSION);
	clp = nfs_find_client(args->craa_addr, 4);
	if (clp == NULL)
		goto out;

	dprintk("NFS: RECALL_ANY callback request from %s\n",
		rpc_peeraddr2str(clp->cl_rpcclient, RPC_DISPLAY_ADDR));

	if (test_bit(RCA4_TYPE_MASK_RDATA_DLG, (const unsigned long *)
		     &args->craa_type_mask))
		flags = FMODE_READ;
	if (test_bit(RCA4_TYPE_MASK_WDATA_DLG, (const unsigned long *)
		     &args->craa_type_mask))
		flags |= FMODE_WRITE;

	if (flags)
		nfs_expire_all_delegation_types(clp, flags);
	status = htonl(NFS4_OK);
out:
	dprintk("%s: exit with status = %d\n", __func__, ntohl(status));
	return status;
}

#endif /* CONFIG_NFS_V4_1 */