fs/nfsd/blocklayout.c

   1 /*
   2  * Copyright (c) 2014-2016 Christoph Hellwig.
   3  */
   4 #include <linux/exportfs.h>
   5 #include <linux/iomap.h>
   6 #include <linux/genhd.h>
   7 #include <linux/slab.h>
   8 #include <linux/pr.h>
   9
  10 #include <linux/nfsd/debug.h>
  11 #include <scsi/scsi_proto.h>
  12 #include <scsi/scsi_common.h>
  13 #include <scsi/scsi_request.h>
  14
  15 #include "blocklayoutxdr.h"
  16 #include "pnfs.h"
  17
  18 #define NFSDDBG_FACILITY        NFSDDBG_PNFS
  19
  20
  21 static __be32
  22 nfsd4_block_proc_layoutget(struct inode *inode, const struct svc_fh *fhp,
  23                 struct nfsd4_layoutget *args)
  24 {
  25         struct nfsd4_layout_seg *seg = &args->lg_seg;
  26         struct super_block *sb = inode->i_sb;
  27         u32 block_size = (1 << inode->i_blkbits);
  28         struct pnfs_block_extent *bex;
  29         struct iomap iomap;
  30         u32 device_generation = 0;
  31         int error;
  32
  33         if (seg->offset & (block_size - 1)) {
  34                 dprintk("pnfsd: I/O misaligned\n");
  35                 goto out_layoutunavailable;
  36         }
  37
  38         /*
  39          * Some clients barf on non-zero block numbers for NONE or INVALID
  40          * layouts, so make sure to zero the whole structure.
  41          */
  42         error = -ENOMEM;
  43         bex = kzalloc(sizeof(*bex), GFP_KERNEL);
  44         if (!bex)
  45                 goto out_error;
  46         args->lg_content = bex;
  47
  48         error = sb->s_export_op->map_blocks(inode, seg->offset, seg->length,
  49                                             &iomap, seg->iomode != IOMODE_READ,
  50                                             &device_generation);
  51         if (error) {
  52                 if (error == -ENXIO)
  53                         goto out_layoutunavailable;
  54                 goto out_error;
  55         }
  56
  57         if (iomap.length < args->lg_minlength) {
  58                 dprintk("pnfsd: extent smaller than minlength\n");
  59                 goto out_layoutunavailable;
  60         }
  61
  62         switch (iomap.type) {
  63         case IOMAP_MAPPED:
  64                 if (seg->iomode == IOMODE_READ)
  65                         bex->es = PNFS_BLOCK_READ_DATA;
  66                 else
  67                         bex->es = PNFS_BLOCK_READWRITE_DATA;
  68                 bex->soff = (iomap.blkno << 9);
  69                 break;
  70         case IOMAP_UNWRITTEN:
  71                 if (seg->iomode & IOMODE_RW) {
  72                         /*
  73                          * Crack monkey special case from section 2.3.1.
  74                          */
  75                         if (args->lg_minlength == 0) {
  76                                 dprintk("pnfsd: no soup for you!\n");
  77                                 goto out_layoutunavailable;
  78                         }
  79
  80                         bex->es = PNFS_BLOCK_INVALID_DATA;
  81                         bex->soff = (iomap.blkno << 9);
  82                         break;
  83                 }
  84                 /*FALLTHRU*/
  85         case IOMAP_HOLE:
  86                 if (seg->iomode == IOMODE_READ) {
  87                         bex->es = PNFS_BLOCK_NONE_DATA;
  88                         break;
  89                 }
  90                 /*FALLTHRU*/
  91         case IOMAP_DELALLOC:
  92         default:
  93                 WARN(1, "pnfsd: filesystem returned %d extent\n", iomap.type);
  94                 goto out_layoutunavailable;
  95         }
  96
  97         error = nfsd4_set_deviceid(&bex->vol_id, fhp, device_generation);
  98         if (error)
  99                 goto out_error;
 100         bex->foff = iomap.offset;
 101         bex->len = iomap.length;
 102
 103         seg->offset = iomap.offset;
 104         seg->length = iomap.length;
 105
 106         dprintk("GET: 0x%llx:0x%llx %d\n", bex->foff, bex->len, bex->es);
 107         return 0;
 108
 109 out_error:
 110         seg->length = 0;
 111         return nfserrno(error);
 112 out_layoutunavailable:
 113         seg->length = 0;
 114         return nfserr_layoutunavailable;
 115 }
 116
 117 static __be32
 118 nfsd4_block_commit_blocks(struct inode *inode, struct nfsd4_layoutcommit *lcp,
 119                 struct iomap *iomaps, int nr_iomaps)
 120 {
 121         loff_t new_size = lcp->lc_last_wr + 1;
 122         struct iattr iattr = { .ia_valid = 0 };
 123         int error;
 124
 125         if (lcp->lc_mtime.tv_nsec == UTIME_NOW ||
 126             timespec_compare(&lcp->lc_mtime, &inode->i_mtime) < 0)
 127                 lcp->lc_mtime = current_time(inode);
 128         iattr.ia_valid |= ATTR_ATIME | ATTR_CTIME | ATTR_MTIME;
 129         iattr.ia_atime = iattr.ia_ctime = iattr.ia_mtime = lcp->lc_mtime;
 130
 131         if (new_size > i_size_read(inode)) {
 132                 iattr.ia_valid |= ATTR_SIZE;
 133                 iattr.ia_size = new_size;
 134         }
 135
 136         error = inode->i_sb->s_export_op->commit_blocks(inode, iomaps,
 137                         nr_iomaps, &iattr);
 138         kfree(iomaps);
 139         return nfserrno(error);
 140 }
 141
 142 #ifdef CONFIG_NFSD_BLOCKLAYOUT
 143 static int
 144 nfsd4_block_get_device_info_simple(struct super_block *sb,
 145                 struct nfsd4_getdeviceinfo *gdp)
 146 {
 147         struct pnfs_block_deviceaddr *dev;
 148         struct pnfs_block_volume *b;
 149
 150         dev = kzalloc(sizeof(struct pnfs_block_deviceaddr) +
 151                       sizeof(struct pnfs_block_volume), GFP_KERNEL);
 152         if (!dev)
 153                 return -ENOMEM;
 154         gdp->gd_device = dev;
 155
 156         dev->nr_volumes = 1;
 157         b = &dev->volumes[0];
 158
 159         b->type = PNFS_BLOCK_VOLUME_SIMPLE;
 160         b->simple.sig_len = PNFS_BLOCK_UUID_LEN;
 161         return sb->s_export_op->get_uuid(sb, b->simple.sig, &b->simple.sig_len,
 162                         &b->simple.offset);
 163 }
 164
 165 static __be32
 166 nfsd4_block_proc_getdeviceinfo(struct super_block *sb,
 167                 struct svc_rqst *rqstp,
 168                 struct nfs4_client *clp,
 169                 struct nfsd4_getdeviceinfo *gdp)
 170 {
 171         if (sb->s_bdev != sb->s_bdev->bd_contains)
 172                 return nfserr_inval;
 173         return nfserrno(nfsd4_block_get_device_info_simple(sb, gdp));
 174 }
 175
 176 static __be32
 177 nfsd4_block_proc_layoutcommit(struct inode *inode,
 178                 struct nfsd4_layoutcommit *lcp)
 179 {
 180         struct iomap *iomaps;
 181         int nr_iomaps;
 182
 183         nr_iomaps = nfsd4_block_decode_layoutupdate(lcp->lc_up_layout,
 184                         lcp->lc_up_len, &iomaps, 1 << inode->i_blkbits);
 185         if (nr_iomaps < 0)
 186                 return nfserrno(nr_iomaps);
 187
 188         return nfsd4_block_commit_blocks(inode, lcp, iomaps, nr_iomaps);
 189 }
 190
 191 const struct nfsd4_layout_ops bl_layout_ops = {
 192         /*
 193          * Pretend that we send notification to the client.  This is a blatant
 194          * lie to force recent Linux clients to cache our device IDs.
 195          * We rarely ever change the device ID, so the harm of leaking deviceids
 196          * for a while isn't too bad.  Unfortunately RFC5661 is a complete mess
 197          * in this regard, but I filed errata 4119 for this a while ago, and
 198          * hopefully the Linux client will eventually start caching deviceids
 199          * without this again.
 200          */
 201         .notify_types           =
 202                         NOTIFY_DEVICEID4_DELETE | NOTIFY_DEVICEID4_CHANGE,
 203         .proc_getdeviceinfo     = nfsd4_block_proc_getdeviceinfo,
 204         .encode_getdeviceinfo   = nfsd4_block_encode_getdeviceinfo,
 205         .proc_layoutget         = nfsd4_block_proc_layoutget,
 206         .encode_layoutget       = nfsd4_block_encode_layoutget,
 207         .proc_layoutcommit      = nfsd4_block_proc_layoutcommit,
 208 };
 209 #endif /* CONFIG_NFSD_BLOCKLAYOUT */
 210
 211 #ifdef CONFIG_NFSD_SCSILAYOUT
 212 static int nfsd4_scsi_identify_device(struct block_device *bdev,
 213                 struct pnfs_block_volume *b)
 214 {
 215         struct request_queue *q = bdev->bd_disk->queue;
 216         struct request *rq;
 217         struct scsi_request *req;
 218         size_t bufflen = 252, len, id_len;
 219         u8 *buf, *d, type, assoc;
 220         int error;
 221
 222         buf = kzalloc(bufflen, GFP_KERNEL);
 223         if (!buf)
 224                 return -ENOMEM;
 225
 226         rq = blk_get_request(q, REQ_OP_SCSI_IN, GFP_KERNEL);
 227         if (IS_ERR(rq)) {
 228                 error = -ENOMEM;
 229                 goto out_free_buf;
 230         }
 231         req = scsi_req(rq);
 232         scsi_req_init(rq);
 233
 234         error = blk_rq_map_kern(q, rq, buf, bufflen, GFP_KERNEL);
 235         if (error)
 236                 goto out_put_request;
 237
 238         req->cmd[0] = INQUIRY;
 239         req->cmd[1] = 1;
 240         req->cmd[2] = 0x83;
 241         req->cmd[3] = bufflen >> 8;
 242         req->cmd[4] = bufflen & 0xff;
 243         req->cmd_len = COMMAND_SIZE(INQUIRY);
 244
 245         error = blk_execute_rq(rq->q, NULL, rq, 1);
 246         if (error) {
 247                 pr_err("pNFS: INQUIRY 0x83 failed with: %x\n",
 248                         rq->errors);
 249                 goto out_put_request;
 250         }
 251
 252         len = (buf[2] << 8) + buf[3] + 4;
 253         if (len > bufflen) {
 254                 pr_err("pNFS: INQUIRY 0x83 response invalid (len = %zd)\n",
 255                         len);
 256                 goto out_put_request;
 257         }
 258
 259         d = buf + 4;
 260         for (d = buf + 4; d < buf + len; d += id_len + 4) {
 261                 id_len = d[3];
 262                 type = d[1] & 0xf;
 263                 assoc = (d[1] >> 4) & 0x3;
 264
 265                 /*
 266                  * We only care about a EUI-64 and NAA designator types
 267                  * with LU association.
 268                  */
 269                 if (assoc != 0x00)
 270                         continue;
 271                 if (type != 0x02 && type != 0x03)
 272                         continue;
 273                 if (id_len != 8 && id_len != 12 && id_len != 16)
 274                         continue;
 275
 276                 b->scsi.code_set = PS_CODE_SET_BINARY;
 277                 b->scsi.designator_type = type == 0x02 ?
 278                         PS_DESIGNATOR_EUI64 : PS_DESIGNATOR_NAA;
 279                 b->scsi.designator_len = id_len;
 280                 memcpy(b->scsi.designator, d + 4, id_len);
 281
 282                 /*
 283                  * If we found a 8 or 12 byte descriptor continue on to
 284                  * see if a 16 byte one is available.  If we find a
 285                  * 16 byte descriptor we're done.
 286                  */
 287                 if (id_len == 16)
 288                         break;
 289         }
 290
 291 out_put_request:
 292         blk_put_request(rq);
 293 out_free_buf:
 294         kfree(buf);
 295         return error;
 296 }
 297
 298 #define NFSD_MDS_PR_KEY         0x0100000000000000ULL
 299
 300 /*
 301  * We use the client ID as a unique key for the reservations.
 302  * This allows us to easily fence a client when recalls fail.
 303  */
 304 static u64 nfsd4_scsi_pr_key(struct nfs4_client *clp)
 305 {
 306         return ((u64)clp->cl_clientid.cl_boot << 32) | clp->cl_clientid.cl_id;
 307 }
 308
 309 static int
 310 nfsd4_block_get_device_info_scsi(struct super_block *sb,
 311                 struct nfs4_client *clp,
 312                 struct nfsd4_getdeviceinfo *gdp)
 313 {
 314         struct pnfs_block_deviceaddr *dev;
 315         struct pnfs_block_volume *b;
 316         const struct pr_ops *ops;
 317         int error;
 318
 319         dev = kzalloc(sizeof(struct pnfs_block_deviceaddr) +
 320                       sizeof(struct pnfs_block_volume), GFP_KERNEL);
 321         if (!dev)
 322                 return -ENOMEM;
 323         gdp->gd_device = dev;
 324
 325         dev->nr_volumes = 1;
 326         b = &dev->volumes[0];
 327
 328         b->type = PNFS_BLOCK_VOLUME_SCSI;
 329         b->scsi.pr_key = nfsd4_scsi_pr_key(clp);
 330
 331         error = nfsd4_scsi_identify_device(sb->s_bdev, b);
 332         if (error)
 333                 return error;
 334
 335         ops = sb->s_bdev->bd_disk->fops->pr_ops;
 336         if (!ops) {
 337                 pr_err("pNFS: device %s does not support PRs.\n",
 338                         sb->s_id);
 339                 return -EINVAL;
 340         }
 341
 342         error = ops->pr_register(sb->s_bdev, 0, NFSD_MDS_PR_KEY, true);
 343         if (error) {
 344                 pr_err("pNFS: failed to register key for device %s.\n",
 345                         sb->s_id);
 346                 return -EINVAL;
 347         }
 348
 349         error = ops->pr_reserve(sb->s_bdev, NFSD_MDS_PR_KEY,
 350                         PR_EXCLUSIVE_ACCESS_REG_ONLY, 0);
 351         if (error) {
 352                 pr_err("pNFS: failed to reserve device %s.\n",
 353                         sb->s_id);
 354                 return -EINVAL;
 355         }
 356
 357         return 0;
 358 }
 359
 360 static __be32
 361 nfsd4_scsi_proc_getdeviceinfo(struct super_block *sb,
 362                 struct svc_rqst *rqstp,
 363                 struct nfs4_client *clp,
 364                 struct nfsd4_getdeviceinfo *gdp)
 365 {
 366         if (sb->s_bdev != sb->s_bdev->bd_contains)
 367                 return nfserr_inval;
 368         return nfserrno(nfsd4_block_get_device_info_scsi(sb, clp, gdp));
 369 }
 370 static __be32
 371 nfsd4_scsi_proc_layoutcommit(struct inode *inode,
 372                 struct nfsd4_layoutcommit *lcp)
 373 {
 374         struct iomap *iomaps;
 375         int nr_iomaps;
 376
 377         nr_iomaps = nfsd4_scsi_decode_layoutupdate(lcp->lc_up_layout,
 378                         lcp->lc_up_len, &iomaps, 1 << inode->i_blkbits);
 379         if (nr_iomaps < 0)
 380                 return nfserrno(nr_iomaps);
 381
 382         return nfsd4_block_commit_blocks(inode, lcp, iomaps, nr_iomaps);
 383 }
 384
 385 static void
 386 nfsd4_scsi_fence_client(struct nfs4_layout_stateid *ls)
 387 {
 388         struct nfs4_client *clp = ls->ls_stid.sc_client;
 389         struct block_device *bdev = ls->ls_file->f_path.mnt->mnt_sb->s_bdev;
 390
 391         bdev->bd_disk->fops->pr_ops->pr_preempt(bdev, NFSD_MDS_PR_KEY,
 392                         nfsd4_scsi_pr_key(clp), 0, true);
 393 }
 394
 395 const struct nfsd4_layout_ops scsi_layout_ops = {
 396         /*
 397          * Pretend that we send notification to the client.  This is a blatant
 398          * lie to force recent Linux clients to cache our device IDs.
 399          * We rarely ever change the device ID, so the harm of leaking deviceids
 400          * for a while isn't too bad.  Unfortunately RFC5661 is a complete mess
 401          * in this regard, but I filed errata 4119 for this a while ago, and
 402          * hopefully the Linux client will eventually start caching deviceids
 403          * without this again.
 404          */
 405         .notify_types           =
 406                         NOTIFY_DEVICEID4_DELETE | NOTIFY_DEVICEID4_CHANGE,
 407         .proc_getdeviceinfo     = nfsd4_scsi_proc_getdeviceinfo,
 408         .encode_getdeviceinfo   = nfsd4_block_encode_getdeviceinfo,
 409         .proc_layoutget         = nfsd4_block_proc_layoutget,
 410         .encode_layoutget       = nfsd4_block_encode_layoutget,
 411         .proc_layoutcommit      = nfsd4_scsi_proc_layoutcommit,
 412         .fence_client           = nfsd4_scsi_fence_client,
 413 };
 414 #endif /* CONFIG_NFSD_SCSILAYOUT */