xref: /linux/fs/nfs/filelayout/filelayoutdev.c (revision 6e7fd890f1d6ac83805409e9c346240de2705584)
1 /*
2  *  Device operations for the pnfs nfs4 file layout driver.
3  *
4  *  Copyright (c) 2002
5  *  The Regents of the University of Michigan
6  *  All Rights Reserved
7  *
8  *  Dean Hildebrand <dhildebz@umich.edu>
9  *  Garth Goodson   <Garth.Goodson@netapp.com>
10  *
11  *  Permission is granted to use, copy, create derivative works, and
12  *  redistribute this software and such derivative works for any purpose,
13  *  so long as the name of the University of Michigan is not used in
14  *  any advertising or publicity pertaining to the use or distribution
15  *  of this software without specific, written prior authorization. If
16  *  the above copyright notice or any other identification of the
17  *  University of Michigan is included in any copy of any portion of
18  *  this software, then the disclaimer below must also be included.
19  *
20  *  This software is provided as is, without representation or warranty
21  *  of any kind either express or implied, including without limitation
22  *  the implied warranties of merchantability, fitness for a particular
23  *  purpose, or noninfringement.  The Regents of the University of
24  *  Michigan shall not be liable for any damages, including special,
25  *  indirect, incidental, or consequential damages, with respect to any
26  *  claim arising out of or in connection with the use of the software,
27  *  even if it has been or is hereafter advised of the possibility of
28  *  such damages.
29  */
30 
31 #include <linux/nfs_fs.h>
32 #include <linux/vmalloc.h>
33 #include <linux/module.h>
34 
35 #include "../internal.h"
36 #include "../nfs4session.h"
37 #include "filelayout.h"
38 #include "../nfs4trace.h"
39 
40 #define NFSDBG_FACILITY		NFSDBG_PNFS_LD
41 
42 static unsigned int dataserver_timeo = NFS4_DEF_DS_TIMEO;
43 static unsigned int dataserver_retrans = NFS4_DEF_DS_RETRANS;
44 
45 void
46 nfs4_fl_free_deviceid(struct nfs4_file_layout_dsaddr *dsaddr)
47 {
48 	struct nfs4_pnfs_ds *ds;
49 	int i;
50 
51 	nfs4_print_deviceid(&dsaddr->id_node.deviceid);
52 
53 	for (i = 0; i < dsaddr->ds_num; i++) {
54 		ds = dsaddr->ds_list[i];
55 		if (ds != NULL)
56 			nfs4_pnfs_ds_put(ds);
57 	}
58 	kfree(dsaddr->stripe_indices);
59 	kfree_rcu(dsaddr, id_node.rcu);
60 }
61 
62 /* Decode opaque device data and return the result */
63 struct nfs4_file_layout_dsaddr *
64 nfs4_fl_alloc_deviceid_node(struct nfs_server *server, struct pnfs_device *pdev,
65 		gfp_t gfp_flags)
66 {
67 	int i;
68 	u32 cnt, num;
69 	u8 *indexp;
70 	__be32 *p;
71 	u8 *stripe_indices;
72 	u8 max_stripe_index;
73 	struct nfs4_file_layout_dsaddr *dsaddr = NULL;
74 	struct xdr_stream stream;
75 	struct xdr_buf buf;
76 	struct page *scratch;
77 	struct list_head dsaddrs;
78 	struct nfs4_pnfs_ds_addr *da;
79 
80 	/* set up xdr stream */
81 	scratch = alloc_page(gfp_flags);
82 	if (!scratch)
83 		goto out_err;
84 
85 	xdr_init_decode_pages(&stream, &buf, pdev->pages, pdev->pglen);
86 	xdr_set_scratch_page(&stream, scratch);
87 
88 	/* Get the stripe count (number of stripe index) */
89 	p = xdr_inline_decode(&stream, 4);
90 	if (unlikely(!p))
91 		goto out_err_free_scratch;
92 
93 	cnt = be32_to_cpup(p);
94 	dprintk("%s stripe count  %d\n", __func__, cnt);
95 	if (cnt > NFS4_PNFS_MAX_STRIPE_CNT) {
96 		printk(KERN_WARNING "NFS: %s: stripe count %d greater than "
97 		       "supported maximum %d\n", __func__,
98 			cnt, NFS4_PNFS_MAX_STRIPE_CNT);
99 		goto out_err_free_scratch;
100 	}
101 
102 	/* read stripe indices */
103 	stripe_indices = kcalloc(cnt, sizeof(u8), gfp_flags);
104 	if (!stripe_indices)
105 		goto out_err_free_scratch;
106 
107 	p = xdr_inline_decode(&stream, cnt << 2);
108 	if (unlikely(!p))
109 		goto out_err_free_stripe_indices;
110 
111 	indexp = &stripe_indices[0];
112 	max_stripe_index = 0;
113 	for (i = 0; i < cnt; i++) {
114 		*indexp = be32_to_cpup(p++);
115 		max_stripe_index = max(max_stripe_index, *indexp);
116 		indexp++;
117 	}
118 
119 	/* Check the multipath list count */
120 	p = xdr_inline_decode(&stream, 4);
121 	if (unlikely(!p))
122 		goto out_err_free_stripe_indices;
123 
124 	num = be32_to_cpup(p);
125 	dprintk("%s ds_num %u\n", __func__, num);
126 	if (num > NFS4_PNFS_MAX_MULTI_CNT) {
127 		printk(KERN_WARNING "NFS: %s: multipath count %d greater than "
128 			"supported maximum %d\n", __func__,
129 			num, NFS4_PNFS_MAX_MULTI_CNT);
130 		goto out_err_free_stripe_indices;
131 	}
132 
133 	/* validate stripe indices are all < num */
134 	if (max_stripe_index >= num) {
135 		printk(KERN_WARNING "NFS: %s: stripe index %u >= num ds %u\n",
136 			__func__, max_stripe_index, num);
137 		goto out_err_free_stripe_indices;
138 	}
139 
140 	dsaddr = kzalloc(struct_size(dsaddr, ds_list, num), gfp_flags);
141 	if (!dsaddr)
142 		goto out_err_free_stripe_indices;
143 
144 	dsaddr->stripe_count = cnt;
145 	dsaddr->stripe_indices = stripe_indices;
146 	stripe_indices = NULL;
147 	dsaddr->ds_num = num;
148 	nfs4_init_deviceid_node(&dsaddr->id_node, server, &pdev->dev_id);
149 
150 	INIT_LIST_HEAD(&dsaddrs);
151 
152 	for (i = 0; i < dsaddr->ds_num; i++) {
153 		int j;
154 		u32 mp_count;
155 
156 		p = xdr_inline_decode(&stream, 4);
157 		if (unlikely(!p))
158 			goto out_err_free_deviceid;
159 
160 		mp_count = be32_to_cpup(p); /* multipath count */
161 		for (j = 0; j < mp_count; j++) {
162 			da = nfs4_decode_mp_ds_addr(server->nfs_client->cl_net,
163 						    &stream, gfp_flags);
164 			if (da)
165 				list_add_tail(&da->da_node, &dsaddrs);
166 		}
167 		if (list_empty(&dsaddrs)) {
168 			dprintk("%s: no suitable DS addresses found\n",
169 				__func__);
170 			goto out_err_free_deviceid;
171 		}
172 
173 		dsaddr->ds_list[i] = nfs4_pnfs_ds_add(&dsaddrs, gfp_flags);
174 		if (!dsaddr->ds_list[i])
175 			goto out_err_drain_dsaddrs;
176 		trace_fl_getdevinfo(server, &pdev->dev_id, dsaddr->ds_list[i]->ds_remotestr);
177 
178 		/* If DS was already in cache, free ds addrs */
179 		while (!list_empty(&dsaddrs)) {
180 			da = list_first_entry(&dsaddrs,
181 					      struct nfs4_pnfs_ds_addr,
182 					      da_node);
183 			list_del_init(&da->da_node);
184 			kfree(da->da_remotestr);
185 			kfree(da);
186 		}
187 	}
188 
189 	__free_page(scratch);
190 	return dsaddr;
191 
192 out_err_drain_dsaddrs:
193 	while (!list_empty(&dsaddrs)) {
194 		da = list_first_entry(&dsaddrs, struct nfs4_pnfs_ds_addr,
195 				      da_node);
196 		list_del_init(&da->da_node);
197 		kfree(da->da_remotestr);
198 		kfree(da);
199 	}
200 out_err_free_deviceid:
201 	nfs4_fl_free_deviceid(dsaddr);
202 	/* stripe_indicies was part of dsaddr */
203 	goto out_err_free_scratch;
204 out_err_free_stripe_indices:
205 	kfree(stripe_indices);
206 out_err_free_scratch:
207 	__free_page(scratch);
208 out_err:
209 	dprintk("%s ERROR: returning NULL\n", __func__);
210 	return NULL;
211 }
212 
213 void
214 nfs4_fl_put_deviceid(struct nfs4_file_layout_dsaddr *dsaddr)
215 {
216 	nfs4_put_deviceid_node(&dsaddr->id_node);
217 }
218 
219 /*
220  * Want res = (offset - layout->pattern_offset)/ layout->stripe_unit
221  * Then: ((res + fsi) % dsaddr->stripe_count)
222  */
223 u32
224 nfs4_fl_calc_j_index(struct pnfs_layout_segment *lseg, loff_t offset)
225 {
226 	struct nfs4_filelayout_segment *flseg = FILELAYOUT_LSEG(lseg);
227 	u64 tmp;
228 
229 	tmp = offset - flseg->pattern_offset;
230 	do_div(tmp, flseg->stripe_unit);
231 	tmp += flseg->first_stripe_index;
232 	return do_div(tmp, flseg->dsaddr->stripe_count);
233 }
234 
235 u32
236 nfs4_fl_calc_ds_index(struct pnfs_layout_segment *lseg, u32 j)
237 {
238 	return FILELAYOUT_LSEG(lseg)->dsaddr->stripe_indices[j];
239 }
240 
241 struct nfs_fh *
242 nfs4_fl_select_ds_fh(struct pnfs_layout_segment *lseg, u32 j)
243 {
244 	struct nfs4_filelayout_segment *flseg = FILELAYOUT_LSEG(lseg);
245 	u32 i;
246 
247 	if (flseg->stripe_type == STRIPE_SPARSE) {
248 		if (flseg->num_fh == 1)
249 			i = 0;
250 		else if (flseg->num_fh == 0)
251 			/* Use the MDS OPEN fh set in nfs_read_rpcsetup */
252 			return NULL;
253 		else
254 			i = nfs4_fl_calc_ds_index(lseg, j);
255 	} else
256 		i = j;
257 	return flseg->fh_array[i];
258 }
259 
260 /* Upon return, either ds is connected, or ds is NULL */
261 struct nfs4_pnfs_ds *
262 nfs4_fl_prepare_ds(struct pnfs_layout_segment *lseg, u32 ds_idx)
263 {
264 	struct nfs4_file_layout_dsaddr *dsaddr = FILELAYOUT_LSEG(lseg)->dsaddr;
265 	struct nfs4_pnfs_ds *ds = dsaddr->ds_list[ds_idx];
266 	struct nfs4_deviceid_node *devid = FILELAYOUT_DEVID_NODE(lseg);
267 	struct nfs4_pnfs_ds *ret = ds;
268 	struct nfs_server *s = NFS_SERVER(lseg->pls_layout->plh_inode);
269 	int status;
270 
271 	if (ds == NULL) {
272 		printk(KERN_ERR "NFS: %s: No data server for offset index %d\n",
273 			__func__, ds_idx);
274 		pnfs_generic_mark_devid_invalid(devid);
275 		goto out;
276 	}
277 	smp_rmb();
278 	if (ds->ds_clp)
279 		goto out_test_devid;
280 
281 	status = nfs4_pnfs_ds_connect(s, ds, devid, dataserver_timeo,
282 			     dataserver_retrans, 4,
283 			     s->nfs_client->cl_minorversion);
284 	if (status) {
285 		nfs4_mark_deviceid_unavailable(devid);
286 		ret = NULL;
287 		goto out;
288 	}
289 
290 out_test_devid:
291 	if (ret->ds_clp == NULL ||
292 	    filelayout_test_devid_unavailable(devid))
293 		ret = NULL;
294 out:
295 	return ret;
296 }
297 
298 module_param(dataserver_retrans, uint, 0644);
299 MODULE_PARM_DESC(dataserver_retrans, "The  number of times the NFSv4.1 client "
300 			"retries a request before it attempts further "
301 			" recovery  action.");
302 module_param(dataserver_timeo, uint, 0644);
303 MODULE_PARM_DESC(dataserver_timeo, "The time (in tenths of a second) the "
304 			"NFSv4.1  client  waits for a response from a "
305 			" data server before it retries an NFS request.");
306