root/fs/nfsd/blocklayout.c

DEFINITIONS

1. nfsd4_block_proc_layoutget
2. nfsd4_block_commit_blocks
3. nfsd4_block_get_device_info_simple
4. nfsd4_block_proc_getdeviceinfo
5. nfsd4_block_proc_layoutcommit
6. nfsd4_scsi_identify_device
7. nfsd4_scsi_pr_key
8. nfsd4_block_get_device_info_scsi
9. nfsd4_scsi_proc_getdeviceinfo
10. nfsd4_scsi_proc_layoutcommit
11. nfsd4_scsi_fence_client

   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/genhd.h>
   8 #include <linux/slab.h>
   9 #include <linux/pr.h>
  10 
  11 #include <linux/nfsd/debug.h>
  12 #include <scsi/scsi_proto.h>
  13 #include <scsi/scsi_common.h>
  14 #include <scsi/scsi_request.h>
  15 
  16 #include "blocklayoutxdr.h"
  17 #include "pnfs.h"
  18 #include "filecache.h"
  19 
  20 #define NFSDDBG_FACILITY        NFSDDBG_PNFS
  21 
  22 
  23 static __be32
  24 nfsd4_block_proc_layoutget(struct inode *inode, const struct svc_fh *fhp,
  25                 struct nfsd4_layoutget *args)
  26 {
  27         struct nfsd4_layout_seg *seg = &args->lg_seg;
  28         struct super_block *sb = inode->i_sb;
  29         u32 block_size = i_blocksize(inode);
  30         struct pnfs_block_extent *bex;
  31         struct iomap iomap;
  32         u32 device_generation = 0;
  33         int error;
  34 
  35         if (seg->offset & (block_size - 1)) {
  36                 dprintk("pnfsd: I/O misaligned\n");
  37                 goto out_layoutunavailable;
  38         }
  39 
  40         /*
  41          * Some clients barf on non-zero block numbers for NONE or INVALID
  42          * layouts, so make sure to zero the whole structure.
  43          */
  44         error = -ENOMEM;
  45         bex = kzalloc(sizeof(*bex), GFP_KERNEL);
  46         if (!bex)
  47                 goto out_error;
  48         args->lg_content = bex;
  49 
  50         error = sb->s_export_op->map_blocks(inode, seg->offset, seg->length,
  51                                             &iomap, seg->iomode != IOMODE_READ,
  52                                             &device_generation);
  53         if (error) {
  54                 if (error == -ENXIO)
  55                         goto out_layoutunavailable;
  56                 goto out_error;
  57         }
  58 
  59         if (iomap.length < args->lg_minlength) {
  60                 dprintk("pnfsd: extent smaller than minlength\n");
  61                 goto out_layoutunavailable;
  62         }
  63 
  64         switch (iomap.type) {
  65         case IOMAP_MAPPED:
  66                 if (seg->iomode == IOMODE_READ)
  67                         bex->es = PNFS_BLOCK_READ_DATA;
  68                 else
  69                         bex->es = PNFS_BLOCK_READWRITE_DATA;
  70                 bex->soff = iomap.addr;
  71                 break;
  72         case IOMAP_UNWRITTEN:
  73                 if (seg->iomode & IOMODE_RW) {
  74                         /*
  75                          * Crack monkey special case from section 2.3.1.
  76                          */
  77                         if (args->lg_minlength == 0) {
  78                                 dprintk("pnfsd: no soup for you!\n");
  79                                 goto out_layoutunavailable;
  80                         }
  81 
  82                         bex->es = PNFS_BLOCK_INVALID_DATA;
  83                         bex->soff = iomap.addr;
  84                         break;
  85                 }
  86                 /*FALLTHRU*/
  87         case IOMAP_HOLE:
  88                 if (seg->iomode == IOMODE_READ) {
  89                         bex->es = PNFS_BLOCK_NONE_DATA;
  90                         break;
  91                 }
  92                 /*FALLTHRU*/
  93         case IOMAP_DELALLOC:
  94         default:
  95                 WARN(1, "pnfsd: filesystem returned %d extent\n", iomap.type);
  96                 goto out_layoutunavailable;
  97         }
  98 
  99         error = nfsd4_set_deviceid(&bex->vol_id, fhp, device_generation);
 100         if (error)
 101                 goto out_error;
 102         bex->foff = iomap.offset;
 103         bex->len = iomap.length;
 104 
 105         seg->offset = iomap.offset;
 106         seg->length = iomap.length;
 107 
 108         dprintk("GET: 0x%llx:0x%llx %d\n", bex->foff, bex->len, bex->es);
 109         return 0;
 110 
 111 out_error:
 112         seg->length = 0;
 113         return nfserrno(error);
 114 out_layoutunavailable:
 115         seg->length = 0;
 116         return nfserr_layoutunavailable;
 117 }
 118 
 119 static __be32
 120 nfsd4_block_commit_blocks(struct inode *inode, struct nfsd4_layoutcommit *lcp,
 121                 struct iomap *iomaps, int nr_iomaps)
 122 {
 123         loff_t new_size = lcp->lc_last_wr + 1;
 124         struct iattr iattr = { .ia_valid = 0 };
 125         int error;
 126 
 127         if (lcp->lc_mtime.tv_nsec == UTIME_NOW ||
 128             timespec64_compare(&lcp->lc_mtime, &inode->i_mtime) < 0)
 129                 lcp->lc_mtime = current_time(inode);
 130         iattr.ia_valid |= ATTR_ATIME | ATTR_CTIME | ATTR_MTIME;
 131         iattr.ia_atime = iattr.ia_ctime = iattr.ia_mtime = lcp->lc_mtime;
 132 
 133         if (new_size > i_size_read(inode)) {
 134                 iattr.ia_valid |= ATTR_SIZE;
 135                 iattr.ia_size = new_size;
 136         }
 137 
 138         error = inode->i_sb->s_export_op->commit_blocks(inode, iomaps,
 139                         nr_iomaps, &iattr);
 140         kfree(iomaps);
 141         return nfserrno(error);
 142 }
 143 
 144 #ifdef CONFIG_NFSD_BLOCKLAYOUT
 145 static int
 146 nfsd4_block_get_device_info_simple(struct super_block *sb,
 147                 struct nfsd4_getdeviceinfo *gdp)
 148 {
 149         struct pnfs_block_deviceaddr *dev;
 150         struct pnfs_block_volume *b;
 151 
 152         dev = kzalloc(sizeof(struct pnfs_block_deviceaddr) +
 153                       sizeof(struct pnfs_block_volume), GFP_KERNEL);
 154         if (!dev)
 155                 return -ENOMEM;
 156         gdp->gd_device = dev;
 157 
 158         dev->nr_volumes = 1;
 159         b = &dev->volumes[0];
 160 
 161         b->type = PNFS_BLOCK_VOLUME_SIMPLE;
 162         b->simple.sig_len = PNFS_BLOCK_UUID_LEN;
 163         return sb->s_export_op->get_uuid(sb, b->simple.sig, &b->simple.sig_len,
 164                         &b->simple.offset);
 165 }
 166 
 167 static __be32
 168 nfsd4_block_proc_getdeviceinfo(struct super_block *sb,
 169                 struct svc_rqst *rqstp,
 170                 struct nfs4_client *clp,
 171                 struct nfsd4_getdeviceinfo *gdp)
 172 {
 173         if (sb->s_bdev != sb->s_bdev->bd_contains)
 174                 return nfserr_inval;
 175         return nfserrno(nfsd4_block_get_device_info_simple(sb, gdp));
 176 }
 177 
 178 static __be32
 179 nfsd4_block_proc_layoutcommit(struct inode *inode,
 180                 struct nfsd4_layoutcommit *lcp)
 181 {
 182         struct iomap *iomaps;
 183         int nr_iomaps;
 184 
 185         nr_iomaps = nfsd4_block_decode_layoutupdate(lcp->lc_up_layout,
 186                         lcp->lc_up_len, &iomaps, i_blocksize(inode));
 187         if (nr_iomaps < 0)
 188                 return nfserrno(nr_iomaps);
 189 
 190         return nfsd4_block_commit_blocks(inode, lcp, iomaps, nr_iomaps);
 191 }
 192 
 193 const struct nfsd4_layout_ops bl_layout_ops = {
 194         /*
 195          * Pretend that we send notification to the client.  This is a blatant
 196          * lie to force recent Linux clients to cache our device IDs.
 197          * We rarely ever change the device ID, so the harm of leaking deviceids
 198          * for a while isn't too bad.  Unfortunately RFC5661 is a complete mess
 199          * in this regard, but I filed errata 4119 for this a while ago, and
 200          * hopefully the Linux client will eventually start caching deviceids
 201          * without this again.
 202          */
 203         .notify_types           =
 204                         NOTIFY_DEVICEID4_DELETE | NOTIFY_DEVICEID4_CHANGE,
 205         .proc_getdeviceinfo     = nfsd4_block_proc_getdeviceinfo,
 206         .encode_getdeviceinfo   = nfsd4_block_encode_getdeviceinfo,
 207         .proc_layoutget         = nfsd4_block_proc_layoutget,
 208         .encode_layoutget       = nfsd4_block_encode_layoutget,
 209         .proc_layoutcommit      = nfsd4_block_proc_layoutcommit,
 210 };
 211 #endif /* CONFIG_NFSD_BLOCKLAYOUT */
 212 
 213 #ifdef CONFIG_NFSD_SCSILAYOUT
 214 static int nfsd4_scsi_identify_device(struct block_device *bdev,
 215                 struct pnfs_block_volume *b)
 216 {
 217         struct request_queue *q = bdev->bd_disk->queue;
 218         struct request *rq;
 219         struct scsi_request *req;
 220         /*
 221          * The allocation length (passed in bytes 3 and 4 of the INQUIRY
 222          * command descriptor block) specifies the number of bytes that have
 223          * been allocated for the data-in buffer.
 224          * 252 is the highest one-byte value that is a multiple of 4.
 225          * 65532 is the highest two-byte value that is a multiple of 4.
 226          */
 227         size_t bufflen = 252, maxlen = 65532, len, id_len;
 228         u8 *buf, *d, type, assoc;
 229         int retries = 1, error;
 230 
 231         if (WARN_ON_ONCE(!blk_queue_scsi_passthrough(q)))
 232                 return -EINVAL;
 233 
 234 again:
 235         buf = kzalloc(bufflen, GFP_KERNEL);
 236         if (!buf)
 237                 return -ENOMEM;
 238 
 239         rq = blk_get_request(q, REQ_OP_SCSI_IN, 0);
 240         if (IS_ERR(rq)) {
 241                 error = -ENOMEM;
 242                 goto out_free_buf;
 243         }
 244         req = scsi_req(rq);
 245 
 246         error = blk_rq_map_kern(q, rq, buf, bufflen, GFP_KERNEL);
 247         if (error)
 248                 goto out_put_request;
 249 
 250         req->cmd[0] = INQUIRY;
 251         req->cmd[1] = 1;
 252         req->cmd[2] = 0x83;
 253         req->cmd[3] = bufflen >> 8;
 254         req->cmd[4] = bufflen & 0xff;
 255         req->cmd_len = COMMAND_SIZE(INQUIRY);
 256 
 257         blk_execute_rq(rq->q, NULL, rq, 1);
 258         if (req->result) {
 259                 pr_err("pNFS: INQUIRY 0x83 failed with: %x\n",
 260                         req->result);
 261                 error = -EIO;
 262                 goto out_put_request;
 263         }
 264 
 265         len = (buf[2] << 8) + buf[3] + 4;
 266         if (len > bufflen) {
 267                 if (len <= maxlen && retries--) {
 268                         blk_put_request(rq);
 269                         kfree(buf);
 270                         bufflen = len;
 271                         goto again;
 272                 }
 273                 pr_err("pNFS: INQUIRY 0x83 response invalid (len = %zd)\n",
 274                         len);
 275                 goto out_put_request;
 276         }
 277 
 278         d = buf + 4;
 279         for (d = buf + 4; d < buf + len; d += id_len + 4) {
 280                 id_len = d[3];
 281                 type = d[1] & 0xf;
 282                 assoc = (d[1] >> 4) & 0x3;
 283 
 284                 /*
 285                  * We only care about a EUI-64 and NAA designator types
 286                  * with LU association.
 287                  */
 288                 if (assoc != 0x00)
 289                         continue;
 290                 if (type != 0x02 && type != 0x03)
 291                         continue;
 292                 if (id_len != 8 && id_len != 12 && id_len != 16)
 293                         continue;
 294 
 295                 b->scsi.code_set = PS_CODE_SET_BINARY;
 296                 b->scsi.designator_type = type == 0x02 ?
 297                         PS_DESIGNATOR_EUI64 : PS_DESIGNATOR_NAA;
 298                 b->scsi.designator_len = id_len;
 299                 memcpy(b->scsi.designator, d + 4, id_len);
 300 
 301                 /*
 302                  * If we found a 8 or 12 byte descriptor continue on to
 303                  * see if a 16 byte one is available.  If we find a
 304                  * 16 byte descriptor we're done.
 305                  */
 306                 if (id_len == 16)
 307                         break;
 308         }
 309 
 310 out_put_request:
 311         blk_put_request(rq);
 312 out_free_buf:
 313         kfree(buf);
 314         return error;
 315 }
 316 
 317 #define NFSD_MDS_PR_KEY         0x0100000000000000ULL
 318 
 319 /*
 320  * We use the client ID as a unique key for the reservations.
 321  * This allows us to easily fence a client when recalls fail.
 322  */
 323 static u64 nfsd4_scsi_pr_key(struct nfs4_client *clp)
 324 {
 325         return ((u64)clp->cl_clientid.cl_boot << 32) | clp->cl_clientid.cl_id;
 326 }
 327 
 328 static int
 329 nfsd4_block_get_device_info_scsi(struct super_block *sb,
 330                 struct nfs4_client *clp,
 331                 struct nfsd4_getdeviceinfo *gdp)
 332 {
 333         struct pnfs_block_deviceaddr *dev;
 334         struct pnfs_block_volume *b;
 335         const struct pr_ops *ops;
 336         int error;
 337 
 338         dev = kzalloc(sizeof(struct pnfs_block_deviceaddr) +
 339                       sizeof(struct pnfs_block_volume), GFP_KERNEL);
 340         if (!dev)
 341                 return -ENOMEM;
 342         gdp->gd_device = dev;
 343 
 344         dev->nr_volumes = 1;
 345         b = &dev->volumes[0];
 346 
 347         b->type = PNFS_BLOCK_VOLUME_SCSI;
 348         b->scsi.pr_key = nfsd4_scsi_pr_key(clp);
 349 
 350         error = nfsd4_scsi_identify_device(sb->s_bdev, b);
 351         if (error)
 352                 return error;
 353 
 354         ops = sb->s_bdev->bd_disk->fops->pr_ops;
 355         if (!ops) {
 356                 pr_err("pNFS: device %s does not support PRs.\n",
 357                         sb->s_id);
 358                 return -EINVAL;
 359         }
 360 
 361         error = ops->pr_register(sb->s_bdev, 0, NFSD_MDS_PR_KEY, true);
 362         if (error) {
 363                 pr_err("pNFS: failed to register key for device %s.\n",
 364                         sb->s_id);
 365                 return -EINVAL;
 366         }
 367 
 368         error = ops->pr_reserve(sb->s_bdev, NFSD_MDS_PR_KEY,
 369                         PR_EXCLUSIVE_ACCESS_REG_ONLY, 0);
 370         if (error) {
 371                 pr_err("pNFS: failed to reserve device %s.\n",
 372                         sb->s_id);
 373                 return -EINVAL;
 374         }
 375 
 376         return 0;
 377 }
 378 
 379 static __be32
 380 nfsd4_scsi_proc_getdeviceinfo(struct super_block *sb,
 381                 struct svc_rqst *rqstp,
 382                 struct nfs4_client *clp,
 383                 struct nfsd4_getdeviceinfo *gdp)
 384 {
 385         if (sb->s_bdev != sb->s_bdev->bd_contains)
 386                 return nfserr_inval;
 387         return nfserrno(nfsd4_block_get_device_info_scsi(sb, clp, gdp));
 388 }
 389 static __be32
 390 nfsd4_scsi_proc_layoutcommit(struct inode *inode,
 391                 struct nfsd4_layoutcommit *lcp)
 392 {
 393         struct iomap *iomaps;
 394         int nr_iomaps;
 395 
 396         nr_iomaps = nfsd4_scsi_decode_layoutupdate(lcp->lc_up_layout,
 397                         lcp->lc_up_len, &iomaps, i_blocksize(inode));
 398         if (nr_iomaps < 0)
 399                 return nfserrno(nr_iomaps);
 400 
 401         return nfsd4_block_commit_blocks(inode, lcp, iomaps, nr_iomaps);
 402 }
 403 
 404 static void
 405 nfsd4_scsi_fence_client(struct nfs4_layout_stateid *ls)
 406 {
 407         struct nfs4_client *clp = ls->ls_stid.sc_client;
 408         struct block_device *bdev = ls->ls_file->nf_file->f_path.mnt->mnt_sb->s_bdev;
 409 
 410         bdev->bd_disk->fops->pr_ops->pr_preempt(bdev, NFSD_MDS_PR_KEY,
 411                         nfsd4_scsi_pr_key(clp), 0, true);
 412 }
 413 
 414 const struct nfsd4_layout_ops scsi_layout_ops = {
 415         /*
 416          * Pretend that we send notification to the client.  This is a blatant
 417          * lie to force recent Linux clients to cache our device IDs.
 418          * We rarely ever change the device ID, so the harm of leaking deviceids
 419          * for a while isn't too bad.  Unfortunately RFC5661 is a complete mess
 420          * in this regard, but I filed errata 4119 for this a while ago, and
 421          * hopefully the Linux client will eventually start caching deviceids
 422          * without this again.
 423          */
 424         .notify_types           =
 425                         NOTIFY_DEVICEID4_DELETE | NOTIFY_DEVICEID4_CHANGE,
 426         .proc_getdeviceinfo     = nfsd4_scsi_proc_getdeviceinfo,
 427         .encode_getdeviceinfo   = nfsd4_block_encode_getdeviceinfo,
 428         .proc_layoutget         = nfsd4_block_proc_layoutget,
 429         .encode_layoutget       = nfsd4_block_encode_layoutget,
 430         .proc_layoutcommit      = nfsd4_scsi_proc_layoutcommit,
 431         .fence_client           = nfsd4_scsi_fence_client,
 432 };
 433 #endif /* CONFIG_NFSD_SCSILAYOUT */