xref: /openbmc/linux/fs/nfsd/blocklayout.c (revision 110e6f26)
1 /*
2  * Copyright (c) 2014-2016 Christoph Hellwig.
3  */
4 #include <linux/exportfs.h>
5 #include <linux/genhd.h>
6 #include <linux/slab.h>
7 #include <linux/pr.h>
8 
9 #include <linux/nfsd/debug.h>
10 #include <scsi/scsi_proto.h>
11 #include <scsi/scsi_common.h>
12 
13 #include "blocklayoutxdr.h"
14 #include "pnfs.h"
15 
16 #define NFSDDBG_FACILITY	NFSDDBG_PNFS
17 
18 
19 static __be32
20 nfsd4_block_proc_layoutget(struct inode *inode, const struct svc_fh *fhp,
21 		struct nfsd4_layoutget *args)
22 {
23 	struct nfsd4_layout_seg *seg = &args->lg_seg;
24 	struct super_block *sb = inode->i_sb;
25 	u32 block_size = (1 << inode->i_blkbits);
26 	struct pnfs_block_extent *bex;
27 	struct iomap iomap;
28 	u32 device_generation = 0;
29 	int error;
30 
31 	if (seg->offset & (block_size - 1)) {
32 		dprintk("pnfsd: I/O misaligned\n");
33 		goto out_layoutunavailable;
34 	}
35 
36 	/*
37 	 * Some clients barf on non-zero block numbers for NONE or INVALID
38 	 * layouts, so make sure to zero the whole structure.
39 	 */
40 	error = -ENOMEM;
41 	bex = kzalloc(sizeof(*bex), GFP_KERNEL);
42 	if (!bex)
43 		goto out_error;
44 	args->lg_content = bex;
45 
46 	error = sb->s_export_op->map_blocks(inode, seg->offset, seg->length,
47 					    &iomap, seg->iomode != IOMODE_READ,
48 					    &device_generation);
49 	if (error) {
50 		if (error == -ENXIO)
51 			goto out_layoutunavailable;
52 		goto out_error;
53 	}
54 
55 	if (iomap.length < args->lg_minlength) {
56 		dprintk("pnfsd: extent smaller than minlength\n");
57 		goto out_layoutunavailable;
58 	}
59 
60 	switch (iomap.type) {
61 	case IOMAP_MAPPED:
62 		if (seg->iomode == IOMODE_READ)
63 			bex->es = PNFS_BLOCK_READ_DATA;
64 		else
65 			bex->es = PNFS_BLOCK_READWRITE_DATA;
66 		bex->soff = (iomap.blkno << 9);
67 		break;
68 	case IOMAP_UNWRITTEN:
69 		if (seg->iomode & IOMODE_RW) {
70 			/*
71 			 * Crack monkey special case from section 2.3.1.
72 			 */
73 			if (args->lg_minlength == 0) {
74 				dprintk("pnfsd: no soup for you!\n");
75 				goto out_layoutunavailable;
76 			}
77 
78 			bex->es = PNFS_BLOCK_INVALID_DATA;
79 			bex->soff = (iomap.blkno << 9);
80 			break;
81 		}
82 		/*FALLTHRU*/
83 	case IOMAP_HOLE:
84 		if (seg->iomode == IOMODE_READ) {
85 			bex->es = PNFS_BLOCK_NONE_DATA;
86 			break;
87 		}
88 		/*FALLTHRU*/
89 	case IOMAP_DELALLOC:
90 	default:
91 		WARN(1, "pnfsd: filesystem returned %d extent\n", iomap.type);
92 		goto out_layoutunavailable;
93 	}
94 
95 	error = nfsd4_set_deviceid(&bex->vol_id, fhp, device_generation);
96 	if (error)
97 		goto out_error;
98 	bex->foff = iomap.offset;
99 	bex->len = iomap.length;
100 
101 	seg->offset = iomap.offset;
102 	seg->length = iomap.length;
103 
104 	dprintk("GET: 0x%llx:0x%llx %d\n", bex->foff, bex->len, bex->es);
105 	return 0;
106 
107 out_error:
108 	seg->length = 0;
109 	return nfserrno(error);
110 out_layoutunavailable:
111 	seg->length = 0;
112 	return nfserr_layoutunavailable;
113 }
114 
115 static __be32
116 nfsd4_block_commit_blocks(struct inode *inode, struct nfsd4_layoutcommit *lcp,
117 		struct iomap *iomaps, int nr_iomaps)
118 {
119 	loff_t new_size = lcp->lc_last_wr + 1;
120 	struct iattr iattr = { .ia_valid = 0 };
121 	int error;
122 
123 	if (lcp->lc_mtime.tv_nsec == UTIME_NOW ||
124 	    timespec_compare(&lcp->lc_mtime, &inode->i_mtime) < 0)
125 		lcp->lc_mtime = current_fs_time(inode->i_sb);
126 	iattr.ia_valid |= ATTR_ATIME | ATTR_CTIME | ATTR_MTIME;
127 	iattr.ia_atime = iattr.ia_ctime = iattr.ia_mtime = lcp->lc_mtime;
128 
129 	if (new_size > i_size_read(inode)) {
130 		iattr.ia_valid |= ATTR_SIZE;
131 		iattr.ia_size = new_size;
132 	}
133 
134 	error = inode->i_sb->s_export_op->commit_blocks(inode, iomaps,
135 			nr_iomaps, &iattr);
136 	kfree(iomaps);
137 	return nfserrno(error);
138 }
139 
140 #ifdef CONFIG_NFSD_BLOCKLAYOUT
141 static int
142 nfsd4_block_get_device_info_simple(struct super_block *sb,
143 		struct nfsd4_getdeviceinfo *gdp)
144 {
145 	struct pnfs_block_deviceaddr *dev;
146 	struct pnfs_block_volume *b;
147 
148 	dev = kzalloc(sizeof(struct pnfs_block_deviceaddr) +
149 		      sizeof(struct pnfs_block_volume), GFP_KERNEL);
150 	if (!dev)
151 		return -ENOMEM;
152 	gdp->gd_device = dev;
153 
154 	dev->nr_volumes = 1;
155 	b = &dev->volumes[0];
156 
157 	b->type = PNFS_BLOCK_VOLUME_SIMPLE;
158 	b->simple.sig_len = PNFS_BLOCK_UUID_LEN;
159 	return sb->s_export_op->get_uuid(sb, b->simple.sig, &b->simple.sig_len,
160 			&b->simple.offset);
161 }
162 
163 static __be32
164 nfsd4_block_proc_getdeviceinfo(struct super_block *sb,
165 		struct nfs4_client *clp,
166 		struct nfsd4_getdeviceinfo *gdp)
167 {
168 	if (sb->s_bdev != sb->s_bdev->bd_contains)
169 		return nfserr_inval;
170 	return nfserrno(nfsd4_block_get_device_info_simple(sb, gdp));
171 }
172 
173 static __be32
174 nfsd4_block_proc_layoutcommit(struct inode *inode,
175 		struct nfsd4_layoutcommit *lcp)
176 {
177 	struct iomap *iomaps;
178 	int nr_iomaps;
179 
180 	nr_iomaps = nfsd4_block_decode_layoutupdate(lcp->lc_up_layout,
181 			lcp->lc_up_len, &iomaps, 1 << inode->i_blkbits);
182 	if (nr_iomaps < 0)
183 		return nfserrno(nr_iomaps);
184 
185 	return nfsd4_block_commit_blocks(inode, lcp, iomaps, nr_iomaps);
186 }
187 
188 const struct nfsd4_layout_ops bl_layout_ops = {
189 	/*
190 	 * Pretend that we send notification to the client.  This is a blatant
191 	 * lie to force recent Linux clients to cache our device IDs.
192 	 * We rarely ever change the device ID, so the harm of leaking deviceids
193 	 * for a while isn't too bad.  Unfortunately RFC5661 is a complete mess
194 	 * in this regard, but I filed errata 4119 for this a while ago, and
195 	 * hopefully the Linux client will eventually start caching deviceids
196 	 * without this again.
197 	 */
198 	.notify_types		=
199 			NOTIFY_DEVICEID4_DELETE | NOTIFY_DEVICEID4_CHANGE,
200 	.proc_getdeviceinfo	= nfsd4_block_proc_getdeviceinfo,
201 	.encode_getdeviceinfo	= nfsd4_block_encode_getdeviceinfo,
202 	.proc_layoutget		= nfsd4_block_proc_layoutget,
203 	.encode_layoutget	= nfsd4_block_encode_layoutget,
204 	.proc_layoutcommit	= nfsd4_block_proc_layoutcommit,
205 };
206 #endif /* CONFIG_NFSD_BLOCKLAYOUT */
207 
208 #ifdef CONFIG_NFSD_SCSILAYOUT
209 static int nfsd4_scsi_identify_device(struct block_device *bdev,
210 		struct pnfs_block_volume *b)
211 {
212 	struct request_queue *q = bdev->bd_disk->queue;
213 	struct request *rq;
214 	size_t bufflen = 252, len, id_len;
215 	u8 *buf, *d, type, assoc;
216 	int error;
217 
218 	buf = kzalloc(bufflen, GFP_KERNEL);
219 	if (!buf)
220 		return -ENOMEM;
221 
222 	rq = blk_get_request(q, READ, GFP_KERNEL);
223 	if (IS_ERR(rq)) {
224 		error = -ENOMEM;
225 		goto out_free_buf;
226 	}
227 	blk_rq_set_block_pc(rq);
228 
229 	error = blk_rq_map_kern(q, rq, buf, bufflen, GFP_KERNEL);
230 	if (error)
231 		goto out_put_request;
232 
233 	rq->cmd[0] = INQUIRY;
234 	rq->cmd[1] = 1;
235 	rq->cmd[2] = 0x83;
236 	rq->cmd[3] = bufflen >> 8;
237 	rq->cmd[4] = bufflen & 0xff;
238 	rq->cmd_len = COMMAND_SIZE(INQUIRY);
239 
240 	error = blk_execute_rq(rq->q, NULL, rq, 1);
241 	if (error) {
242 		pr_err("pNFS: INQUIRY 0x83 failed with: %x\n",
243 			rq->errors);
244 		goto out_put_request;
245 	}
246 
247 	len = (buf[2] << 8) + buf[3] + 4;
248 	if (len > bufflen) {
249 		pr_err("pNFS: INQUIRY 0x83 response invalid (len = %zd)\n",
250 			len);
251 		goto out_put_request;
252 	}
253 
254 	d = buf + 4;
255 	for (d = buf + 4; d < buf + len; d += id_len + 4) {
256 		id_len = d[3];
257 		type = d[1] & 0xf;
258 		assoc = (d[1] >> 4) & 0x3;
259 
260 		/*
261 		 * We only care about a EUI-64 and NAA designator types
262 		 * with LU association.
263 		 */
264 		if (assoc != 0x00)
265 			continue;
266 		if (type != 0x02 && type != 0x03)
267 			continue;
268 		if (id_len != 8 && id_len != 12 && id_len != 16)
269 			continue;
270 
271 		b->scsi.code_set = PS_CODE_SET_BINARY;
272 		b->scsi.designator_type = type == 0x02 ?
273 			PS_DESIGNATOR_EUI64 : PS_DESIGNATOR_NAA;
274 		b->scsi.designator_len = id_len;
275 		memcpy(b->scsi.designator, d + 4, id_len);
276 
277 		/*
278 		 * If we found a 8 or 12 byte descriptor continue on to
279 		 * see if a 16 byte one is available.  If we find a
280 		 * 16 byte descriptor we're done.
281 		 */
282 		if (id_len == 16)
283 			break;
284 	}
285 
286 out_put_request:
287 	blk_put_request(rq);
288 out_free_buf:
289 	kfree(buf);
290 	return error;
291 }
292 
293 #define NFSD_MDS_PR_KEY		0x0100000000000000
294 
295 /*
296  * We use the client ID as a unique key for the reservations.
297  * This allows us to easily fence a client when recalls fail.
298  */
299 static u64 nfsd4_scsi_pr_key(struct nfs4_client *clp)
300 {
301 	return ((u64)clp->cl_clientid.cl_boot << 32) | clp->cl_clientid.cl_id;
302 }
303 
304 static int
305 nfsd4_block_get_device_info_scsi(struct super_block *sb,
306 		struct nfs4_client *clp,
307 		struct nfsd4_getdeviceinfo *gdp)
308 {
309 	struct pnfs_block_deviceaddr *dev;
310 	struct pnfs_block_volume *b;
311 	const struct pr_ops *ops;
312 	int error;
313 
314 	dev = kzalloc(sizeof(struct pnfs_block_deviceaddr) +
315 		      sizeof(struct pnfs_block_volume), GFP_KERNEL);
316 	if (!dev)
317 		return -ENOMEM;
318 	gdp->gd_device = dev;
319 
320 	dev->nr_volumes = 1;
321 	b = &dev->volumes[0];
322 
323 	b->type = PNFS_BLOCK_VOLUME_SCSI;
324 	b->scsi.pr_key = nfsd4_scsi_pr_key(clp);
325 
326 	error = nfsd4_scsi_identify_device(sb->s_bdev, b);
327 	if (error)
328 		return error;
329 
330 	ops = sb->s_bdev->bd_disk->fops->pr_ops;
331 	if (!ops) {
332 		pr_err("pNFS: device %s does not support PRs.\n",
333 			sb->s_id);
334 		return -EINVAL;
335 	}
336 
337 	error = ops->pr_register(sb->s_bdev, 0, NFSD_MDS_PR_KEY, true);
338 	if (error) {
339 		pr_err("pNFS: failed to register key for device %s.\n",
340 			sb->s_id);
341 		return -EINVAL;
342 	}
343 
344 	error = ops->pr_reserve(sb->s_bdev, NFSD_MDS_PR_KEY,
345 			PR_EXCLUSIVE_ACCESS_REG_ONLY, 0);
346 	if (error) {
347 		pr_err("pNFS: failed to reserve device %s.\n",
348 			sb->s_id);
349 		return -EINVAL;
350 	}
351 
352 	return 0;
353 }
354 
355 static __be32
356 nfsd4_scsi_proc_getdeviceinfo(struct super_block *sb,
357 		struct nfs4_client *clp,
358 		struct nfsd4_getdeviceinfo *gdp)
359 {
360 	if (sb->s_bdev != sb->s_bdev->bd_contains)
361 		return nfserr_inval;
362 	return nfserrno(nfsd4_block_get_device_info_scsi(sb, clp, gdp));
363 }
364 static __be32
365 nfsd4_scsi_proc_layoutcommit(struct inode *inode,
366 		struct nfsd4_layoutcommit *lcp)
367 {
368 	struct iomap *iomaps;
369 	int nr_iomaps;
370 
371 	nr_iomaps = nfsd4_scsi_decode_layoutupdate(lcp->lc_up_layout,
372 			lcp->lc_up_len, &iomaps, 1 << inode->i_blkbits);
373 	if (nr_iomaps < 0)
374 		return nfserrno(nr_iomaps);
375 
376 	return nfsd4_block_commit_blocks(inode, lcp, iomaps, nr_iomaps);
377 }
378 
379 static void
380 nfsd4_scsi_fence_client(struct nfs4_layout_stateid *ls)
381 {
382 	struct nfs4_client *clp = ls->ls_stid.sc_client;
383 	struct block_device *bdev = ls->ls_file->f_path.mnt->mnt_sb->s_bdev;
384 
385 	bdev->bd_disk->fops->pr_ops->pr_preempt(bdev, NFSD_MDS_PR_KEY,
386 			nfsd4_scsi_pr_key(clp), 0, true);
387 }
388 
389 const struct nfsd4_layout_ops scsi_layout_ops = {
390 	/*
391 	 * Pretend that we send notification to the client.  This is a blatant
392 	 * lie to force recent Linux clients to cache our device IDs.
393 	 * We rarely ever change the device ID, so the harm of leaking deviceids
394 	 * for a while isn't too bad.  Unfortunately RFC5661 is a complete mess
395 	 * in this regard, but I filed errata 4119 for this a while ago, and
396 	 * hopefully the Linux client will eventually start caching deviceids
397 	 * without this again.
398 	 */
399 	.notify_types		=
400 			NOTIFY_DEVICEID4_DELETE | NOTIFY_DEVICEID4_CHANGE,
401 	.proc_getdeviceinfo	= nfsd4_scsi_proc_getdeviceinfo,
402 	.encode_getdeviceinfo	= nfsd4_block_encode_getdeviceinfo,
403 	.proc_layoutget		= nfsd4_block_proc_layoutget,
404 	.encode_layoutget	= nfsd4_block_encode_layoutget,
405 	.proc_layoutcommit	= nfsd4_scsi_proc_layoutcommit,
406 	.fence_client		= nfsd4_scsi_fence_client,
407 };
408 #endif /* CONFIG_NFSD_SCSILAYOUT */
409