1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (c) 2014-2016 Christoph Hellwig.
4  */
5 #include <linux/exportfs.h>
6 #include <linux/iomap.h>
7 #include <linux/slab.h>
8 #include <linux/pr.h>
9 
10 #include <linux/nfsd/debug.h>
11 
12 #include "blocklayoutxdr.h"
13 #include "pnfs.h"
14 #include "filecache.h"
15 
16 #define NFSDDBG_FACILITY	NFSDDBG_PNFS
17 
18 
19 static __be32
nfsd4_block_proc_layoutget(struct inode * inode,const struct svc_fh * fhp,struct nfsd4_layoutget * args)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 = i_blocksize(inode);
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.addr;
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.addr;
80 			break;
81 		}
82 		fallthrough;
83 	case IOMAP_HOLE:
84 		if (seg->iomode == IOMODE_READ) {
85 			bex->es = PNFS_BLOCK_NONE_DATA;
86 			break;
87 		}
88 		fallthrough;
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
nfsd4_block_commit_blocks(struct inode * inode,struct nfsd4_layoutcommit * lcp,struct iomap * iomaps,int nr_iomaps)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 	    timespec64_compare(&lcp->lc_mtime, &inode->i_mtime) < 0)
125 		lcp->lc_mtime = current_time(inode);
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
nfsd4_block_get_device_info_simple(struct super_block * sb,struct nfsd4_getdeviceinfo * gdp)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
nfsd4_block_proc_getdeviceinfo(struct super_block * sb,struct svc_rqst * rqstp,struct nfs4_client * clp,struct nfsd4_getdeviceinfo * gdp)164 nfsd4_block_proc_getdeviceinfo(struct super_block *sb,
165 		struct svc_rqst *rqstp,
166 		struct nfs4_client *clp,
167 		struct nfsd4_getdeviceinfo *gdp)
168 {
169 	if (bdev_is_partition(sb->s_bdev))
170 		return nfserr_inval;
171 	return nfserrno(nfsd4_block_get_device_info_simple(sb, gdp));
172 }
173 
174 static __be32
nfsd4_block_proc_layoutcommit(struct inode * inode,struct nfsd4_layoutcommit * lcp)175 nfsd4_block_proc_layoutcommit(struct inode *inode,
176 		struct nfsd4_layoutcommit *lcp)
177 {
178 	struct iomap *iomaps;
179 	int nr_iomaps;
180 
181 	nr_iomaps = nfsd4_block_decode_layoutupdate(lcp->lc_up_layout,
182 			lcp->lc_up_len, &iomaps, i_blocksize(inode));
183 	if (nr_iomaps < 0)
184 		return nfserrno(nr_iomaps);
185 
186 	return nfsd4_block_commit_blocks(inode, lcp, iomaps, nr_iomaps);
187 }
188 
189 const struct nfsd4_layout_ops bl_layout_ops = {
190 	/*
191 	 * Pretend that we send notification to the client.  This is a blatant
192 	 * lie to force recent Linux clients to cache our device IDs.
193 	 * We rarely ever change the device ID, so the harm of leaking deviceids
194 	 * for a while isn't too bad.  Unfortunately RFC5661 is a complete mess
195 	 * in this regard, but I filed errata 4119 for this a while ago, and
196 	 * hopefully the Linux client will eventually start caching deviceids
197 	 * without this again.
198 	 */
199 	.notify_types		=
200 			NOTIFY_DEVICEID4_DELETE | NOTIFY_DEVICEID4_CHANGE,
201 	.proc_getdeviceinfo	= nfsd4_block_proc_getdeviceinfo,
202 	.encode_getdeviceinfo	= nfsd4_block_encode_getdeviceinfo,
203 	.proc_layoutget		= nfsd4_block_proc_layoutget,
204 	.encode_layoutget	= nfsd4_block_encode_layoutget,
205 	.proc_layoutcommit	= nfsd4_block_proc_layoutcommit,
206 };
207 #endif /* CONFIG_NFSD_BLOCKLAYOUT */
208 
209 #ifdef CONFIG_NFSD_SCSILAYOUT
210 #define NFSD_MDS_PR_KEY		0x0100000000000000ULL
211 
212 /*
213  * We use the client ID as a unique key for the reservations.
214  * This allows us to easily fence a client when recalls fail.
215  */
nfsd4_scsi_pr_key(struct nfs4_client * clp)216 static u64 nfsd4_scsi_pr_key(struct nfs4_client *clp)
217 {
218 	return ((u64)clp->cl_clientid.cl_boot << 32) | clp->cl_clientid.cl_id;
219 }
220 
221 static const u8 designator_types[] = {
222 	PS_DESIGNATOR_EUI64,
223 	PS_DESIGNATOR_NAA,
224 };
225 
226 static int
nfsd4_block_get_unique_id(struct gendisk * disk,struct pnfs_block_volume * b)227 nfsd4_block_get_unique_id(struct gendisk *disk, struct pnfs_block_volume *b)
228 {
229 	int ret, i;
230 
231 	for (i = 0; i < ARRAY_SIZE(designator_types); i++) {
232 		u8 type = designator_types[i];
233 
234 		ret = disk->fops->get_unique_id(disk, b->scsi.designator, type);
235 		if (ret > 0) {
236 			b->scsi.code_set = PS_CODE_SET_BINARY;
237 			b->scsi.designator_type = type;
238 			b->scsi.designator_len = ret;
239 			return 0;
240 		}
241 	}
242 
243 	return -EINVAL;
244 }
245 
246 static int
nfsd4_block_get_device_info_scsi(struct super_block * sb,struct nfs4_client * clp,struct nfsd4_getdeviceinfo * gdp)247 nfsd4_block_get_device_info_scsi(struct super_block *sb,
248 		struct nfs4_client *clp,
249 		struct nfsd4_getdeviceinfo *gdp)
250 {
251 	struct pnfs_block_deviceaddr *dev;
252 	struct pnfs_block_volume *b;
253 	const struct pr_ops *ops;
254 	int ret;
255 
256 	dev = kzalloc(sizeof(struct pnfs_block_deviceaddr) +
257 		      sizeof(struct pnfs_block_volume), GFP_KERNEL);
258 	if (!dev)
259 		return -ENOMEM;
260 	gdp->gd_device = dev;
261 
262 	dev->nr_volumes = 1;
263 	b = &dev->volumes[0];
264 
265 	b->type = PNFS_BLOCK_VOLUME_SCSI;
266 	b->scsi.pr_key = nfsd4_scsi_pr_key(clp);
267 
268 	ret = nfsd4_block_get_unique_id(sb->s_bdev->bd_disk, b);
269 	if (ret < 0)
270 		goto out_free_dev;
271 
272 	ret = -EINVAL;
273 	ops = sb->s_bdev->bd_disk->fops->pr_ops;
274 	if (!ops) {
275 		pr_err("pNFS: device %s does not support PRs.\n",
276 			sb->s_id);
277 		goto out_free_dev;
278 	}
279 
280 	ret = ops->pr_register(sb->s_bdev, 0, NFSD_MDS_PR_KEY, true);
281 	if (ret) {
282 		pr_err("pNFS: failed to register key for device %s.\n",
283 			sb->s_id);
284 		goto out_free_dev;
285 	}
286 
287 	ret = ops->pr_reserve(sb->s_bdev, NFSD_MDS_PR_KEY,
288 			PR_EXCLUSIVE_ACCESS_REG_ONLY, 0);
289 	if (ret) {
290 		pr_err("pNFS: failed to reserve device %s.\n",
291 			sb->s_id);
292 		goto out_free_dev;
293 	}
294 
295 	return 0;
296 
297 out_free_dev:
298 	kfree(dev);
299 	return ret;
300 }
301 
302 static __be32
nfsd4_scsi_proc_getdeviceinfo(struct super_block * sb,struct svc_rqst * rqstp,struct nfs4_client * clp,struct nfsd4_getdeviceinfo * gdp)303 nfsd4_scsi_proc_getdeviceinfo(struct super_block *sb,
304 		struct svc_rqst *rqstp,
305 		struct nfs4_client *clp,
306 		struct nfsd4_getdeviceinfo *gdp)
307 {
308 	if (bdev_is_partition(sb->s_bdev))
309 		return nfserr_inval;
310 	return nfserrno(nfsd4_block_get_device_info_scsi(sb, clp, gdp));
311 }
312 static __be32
nfsd4_scsi_proc_layoutcommit(struct inode * inode,struct nfsd4_layoutcommit * lcp)313 nfsd4_scsi_proc_layoutcommit(struct inode *inode,
314 		struct nfsd4_layoutcommit *lcp)
315 {
316 	struct iomap *iomaps;
317 	int nr_iomaps;
318 
319 	nr_iomaps = nfsd4_scsi_decode_layoutupdate(lcp->lc_up_layout,
320 			lcp->lc_up_len, &iomaps, i_blocksize(inode));
321 	if (nr_iomaps < 0)
322 		return nfserrno(nr_iomaps);
323 
324 	return nfsd4_block_commit_blocks(inode, lcp, iomaps, nr_iomaps);
325 }
326 
327 static void
nfsd4_scsi_fence_client(struct nfs4_layout_stateid * ls)328 nfsd4_scsi_fence_client(struct nfs4_layout_stateid *ls)
329 {
330 	struct nfs4_client *clp = ls->ls_stid.sc_client;
331 	struct block_device *bdev = ls->ls_file->nf_file->f_path.mnt->mnt_sb->s_bdev;
332 
333 	bdev->bd_disk->fops->pr_ops->pr_preempt(bdev, NFSD_MDS_PR_KEY,
334 			nfsd4_scsi_pr_key(clp), 0, true);
335 }
336 
337 const struct nfsd4_layout_ops scsi_layout_ops = {
338 	/*
339 	 * Pretend that we send notification to the client.  This is a blatant
340 	 * lie to force recent Linux clients to cache our device IDs.
341 	 * We rarely ever change the device ID, so the harm of leaking deviceids
342 	 * for a while isn't too bad.  Unfortunately RFC5661 is a complete mess
343 	 * in this regard, but I filed errata 4119 for this a while ago, and
344 	 * hopefully the Linux client will eventually start caching deviceids
345 	 * without this again.
346 	 */
347 	.notify_types		=
348 			NOTIFY_DEVICEID4_DELETE | NOTIFY_DEVICEID4_CHANGE,
349 	.proc_getdeviceinfo	= nfsd4_scsi_proc_getdeviceinfo,
350 	.encode_getdeviceinfo	= nfsd4_block_encode_getdeviceinfo,
351 	.proc_layoutget		= nfsd4_block_proc_layoutget,
352 	.encode_layoutget	= nfsd4_block_encode_layoutget,
353 	.proc_layoutcommit	= nfsd4_scsi_proc_layoutcommit,
354 	.fence_client		= nfsd4_scsi_fence_client,
355 };
356 #endif /* CONFIG_NFSD_SCSILAYOUT */
357