fs/nfs/nfs4filelayout.c

   1 /*
   2  *  Module for the pnfs nfs4 file layout driver.
   3  *  Defines all I/O and Policy interface operations, plus code
   4  *  to register itself with the pNFS client.
   5  *
   6  *  Copyright (c) 2002
   7  *  The Regents of the University of Michigan
   8  *  All Rights Reserved
   9  *
  10  *  Dean Hildebrand <dhildebz@umich.edu>
  11  *
  12  *  Permission is granted to use, copy, create derivative works, and
  13  *  redistribute this software and such derivative works for any purpose,
  14  *  so long as the name of the University of Michigan is not used in
  15  *  any advertising or publicity pertaining to the use or distribution
  16  *  of this software without specific, written prior authorization. If
  17  *  the above copyright notice or any other identification of the
  18  *  University of Michigan is included in any copy of any portion of
  19  *  this software, then the disclaimer below must also be included.
  20  *
  21  *  This software is provided as is, without representation or warranty
  22  *  of any kind either express or implied, including without limitation
  23  *  the implied warranties of merchantability, fitness for a particular
  24  *  purpose, or noninfringement.  The Regents of the University of
  25  *  Michigan shall not be liable for any damages, including special,
  26  *  indirect, incidental, or consequential damages, with respect to any
  27  *  claim arising out of or in connection with the use of the software,
  28  *  even if it has been or is hereafter advised of the possibility of
  29  *  such damages.
  30  */
  31
  32 #include <linux/nfs_fs.h>
  33
  34 #include "internal.h"
  35 #include "nfs4filelayout.h"
  36
  37 #define NFSDBG_FACILITY         NFSDBG_PNFS_LD
  38
  39 MODULE_LICENSE("GPL");
  40 MODULE_AUTHOR("Dean Hildebrand <dhildebz@umich.edu>");
  41 MODULE_DESCRIPTION("The NFSv4 file layout driver");
  42
  43 #define FILELAYOUT_POLL_RETRY_MAX     (15*HZ)
  44
  45 static loff_t
  46 filelayout_get_dense_offset(struct nfs4_filelayout_segment *flseg,
  47                             loff_t offset)
  48 {
  49         u32 stripe_width = flseg->stripe_unit * flseg->dsaddr->stripe_count;
  50         u64 tmp;
  51
  52         offset -= flseg->pattern_offset;
  53         tmp = offset;
  54         do_div(tmp, stripe_width);
  55
  56         return tmp * flseg->stripe_unit + do_div(offset, flseg->stripe_unit);
  57 }
  58
  59 /* This function is used by the layout driver to calculate the
  60  * offset of the file on the dserver based on whether the
  61  * layout type is STRIPE_DENSE or STRIPE_SPARSE
  62  */
  63 static loff_t
  64 filelayout_get_dserver_offset(struct pnfs_layout_segment *lseg, loff_t offset)
  65 {
  66         struct nfs4_filelayout_segment *flseg = FILELAYOUT_LSEG(lseg);
  67
  68         switch (flseg->stripe_type) {
  69         case STRIPE_SPARSE:
  70                 return offset;
  71
  72         case STRIPE_DENSE:
  73                 return filelayout_get_dense_offset(flseg, offset);
  74         }
  75
  76         BUG();
  77 }
  78
  79 /* For data server errors we don't recover from */
  80 static void
  81 filelayout_set_lo_fail(struct pnfs_layout_segment *lseg)
  82 {
  83         if (lseg->pls_range.iomode == IOMODE_RW) {
  84                 dprintk("%s Setting layout IOMODE_RW fail bit\n", __func__);
  85                 set_bit(lo_fail_bit(IOMODE_RW), &lseg->pls_layout->plh_flags);
  86         } else {
  87                 dprintk("%s Setting layout IOMODE_READ fail bit\n", __func__);
  88                 set_bit(lo_fail_bit(IOMODE_READ), &lseg->pls_layout->plh_flags);
  89         }
  90 }
  91
  92 static int filelayout_async_handle_error(struct rpc_task *task,
  93                                          struct nfs4_state *state,
  94                                          struct nfs_client *clp,
  95                                          int *reset)
  96 {
  97         if (task->tk_status >= 0)
  98                 return 0;
  99
 100         *reset = 0;
 101
 102         switch (task->tk_status) {
 103         case -NFS4ERR_BADSESSION:
 104         case -NFS4ERR_BADSLOT:
 105         case -NFS4ERR_BAD_HIGH_SLOT:
 106         case -NFS4ERR_DEADSESSION:
 107         case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
 108         case -NFS4ERR_SEQ_FALSE_RETRY:
 109         case -NFS4ERR_SEQ_MISORDERED:
 110                 dprintk("%s ERROR %d, Reset session. Exchangeid "
 111                         "flags 0x%x\n", __func__, task->tk_status,
 112                         clp->cl_exchange_flags);
 113                 nfs4_schedule_session_recovery(clp->cl_session);
 114                 break;
 115         case -NFS4ERR_DELAY:
 116         case -NFS4ERR_GRACE:
 117         case -EKEYEXPIRED:
 118                 rpc_delay(task, FILELAYOUT_POLL_RETRY_MAX);
 119                 break;
 120         default:
 121                 dprintk("%s DS error. Retry through MDS %d\n", __func__,
 122                         task->tk_status);
 123                 *reset = 1;
 124                 break;
 125         }
 126         task->tk_status = 0;
 127         return -EAGAIN;
 128 }
 129
 130 /* NFS_PROTO call done callback routines */
 131
 132 static int filelayout_read_done_cb(struct rpc_task *task,
 133                                 struct nfs_read_data *data)
 134 {
 135         struct nfs_client *clp = data->ds_clp;
 136         int reset = 0;
 137
 138         dprintk("%s DS read\n", __func__);
 139
 140         if (filelayout_async_handle_error(task, data->args.context->state,
 141                                           data->ds_clp, &reset) == -EAGAIN) {
 142                 dprintk("%s calling restart ds_clp %p ds_clp->cl_session %p\n",
 143                         __func__, data->ds_clp, data->ds_clp->cl_session);
 144                 if (reset) {
 145                         filelayout_set_lo_fail(data->lseg);
 146                         nfs4_reset_read(task, data);
 147                         clp = NFS_SERVER(data->inode)->nfs_client;
 148                 }
 149                 nfs_restart_rpc(task, clp);
 150                 return -EAGAIN;
 151         }
 152
 153         return 0;
 154 }
 155
 156 /*
 157  * Call ops for the async read/write cases
 158  * In the case of dense layouts, the offset needs to be reset to its
 159  * original value.
 160  */
 161 static void filelayout_read_prepare(struct rpc_task *task, void *data)
 162 {
 163         struct nfs_read_data *rdata = (struct nfs_read_data *)data;
 164
 165         rdata->read_done_cb = filelayout_read_done_cb;
 166
 167         if (nfs41_setup_sequence(rdata->ds_clp->cl_session,
 168                                 &rdata->args.seq_args, &rdata->res.seq_res,
 169                                 0, task))
 170                 return;
 171
 172         rpc_call_start(task);
 173 }
 174
 175 static void filelayout_read_call_done(struct rpc_task *task, void *data)
 176 {
 177         struct nfs_read_data *rdata = (struct nfs_read_data *)data;
 178
 179         dprintk("--> %s task->tk_status %d\n", __func__, task->tk_status);
 180
 181         /* Note this may cause RPC to be resent */
 182         rdata->mds_ops->rpc_call_done(task, data);
 183 }
 184
 185 static void filelayout_read_release(void *data)
 186 {
 187         struct nfs_read_data *rdata = (struct nfs_read_data *)data;
 188
 189         rdata->mds_ops->rpc_release(data);
 190 }
 191
 192 static int filelayout_write_done_cb(struct rpc_task *task,
 193                                 struct nfs_write_data *data)
 194 {
 195         int reset = 0;
 196
 197         if (filelayout_async_handle_error(task, data->args.context->state,
 198                                           data->ds_clp, &reset) == -EAGAIN) {
 199                 struct nfs_client *clp;
 200
 201                 dprintk("%s calling restart ds_clp %p ds_clp->cl_session %p\n",
 202                         __func__, data->ds_clp, data->ds_clp->cl_session);
 203                 if (reset) {
 204                         filelayout_set_lo_fail(data->lseg);
 205                         nfs4_reset_write(task, data);
 206                         clp = NFS_SERVER(data->inode)->nfs_client;
 207                 } else
 208                         clp = data->ds_clp;
 209                 nfs_restart_rpc(task, clp);
 210                 return -EAGAIN;
 211         }
 212
 213         return 0;
 214 }
 215
 216 static void filelayout_write_prepare(struct rpc_task *task, void *data)
 217 {
 218         struct nfs_write_data *wdata = (struct nfs_write_data *)data;
 219
 220         if (nfs41_setup_sequence(wdata->ds_clp->cl_session,
 221                                 &wdata->args.seq_args, &wdata->res.seq_res,
 222                                 0, task))
 223                 return;
 224
 225         rpc_call_start(task);
 226 }
 227
 228 static void filelayout_write_call_done(struct rpc_task *task, void *data)
 229 {
 230         struct nfs_write_data *wdata = (struct nfs_write_data *)data;
 231
 232         /* Note this may cause RPC to be resent */
 233         wdata->mds_ops->rpc_call_done(task, data);
 234 }
 235
 236 static void filelayout_write_release(void *data)
 237 {
 238         struct nfs_write_data *wdata = (struct nfs_write_data *)data;
 239
 240         wdata->mds_ops->rpc_release(data);
 241 }
 242
 243 struct rpc_call_ops filelayout_read_call_ops = {
 244         .rpc_call_prepare = filelayout_read_prepare,
 245         .rpc_call_done = filelayout_read_call_done,
 246         .rpc_release = filelayout_read_release,
 247 };
 248
 249 struct rpc_call_ops filelayout_write_call_ops = {
 250         .rpc_call_prepare = filelayout_write_prepare,
 251         .rpc_call_done = filelayout_write_call_done,
 252         .rpc_release = filelayout_write_release,
 253 };
 254
 255 static enum pnfs_try_status
 256 filelayout_read_pagelist(struct nfs_read_data *data)
 257 {
 258         struct pnfs_layout_segment *lseg = data->lseg;
 259         struct nfs4_pnfs_ds *ds;
 260         loff_t offset = data->args.offset;
 261         u32 j, idx;
 262         struct nfs_fh *fh;
 263         int status;
 264
 265         dprintk("--> %s ino %lu pgbase %u req %Zu@%llu\n",
 266                 __func__, data->inode->i_ino,
 267                 data->args.pgbase, (size_t)data->args.count, offset);
 268
 269         /* Retrieve the correct rpc_client for the byte range */
 270         j = nfs4_fl_calc_j_index(lseg, offset);
 271         idx = nfs4_fl_calc_ds_index(lseg, j);
 272         ds = nfs4_fl_prepare_ds(lseg, idx);
 273         if (!ds) {
 274                 /* Either layout fh index faulty, or ds connect failed */
 275                 set_bit(lo_fail_bit(IOMODE_RW), &lseg->pls_layout->plh_flags);
 276                 set_bit(lo_fail_bit(IOMODE_READ), &lseg->pls_layout->plh_flags);
 277                 return PNFS_NOT_ATTEMPTED;
 278         }
 279         dprintk("%s USE DS:ip %x %hu\n", __func__,
 280                 ntohl(ds->ds_ip_addr), ntohs(ds->ds_port));
 281
 282         /* No multipath support. Use first DS */
 283         data->ds_clp = ds->ds_clp;
 284         fh = nfs4_fl_select_ds_fh(lseg, j);
 285         if (fh)
 286                 data->args.fh = fh;
 287
 288         data->args.offset = filelayout_get_dserver_offset(lseg, offset);
 289         data->mds_offset = offset;
 290
 291         /* Perform an asynchronous read to ds */
 292         status = nfs_initiate_read(data, ds->ds_clp->cl_rpcclient,
 293                                    &filelayout_read_call_ops);
 294         BUG_ON(status != 0);
 295         return PNFS_ATTEMPTED;
 296 }
 297
 298 /* Perform async writes. */
 299 static enum pnfs_try_status
 300 filelayout_write_pagelist(struct nfs_write_data *data, int sync)
 301 {
 302         struct pnfs_layout_segment *lseg = data->lseg;
 303         struct nfs4_pnfs_ds *ds;
 304         loff_t offset = data->args.offset;
 305         u32 j, idx;
 306         struct nfs_fh *fh;
 307         int status;
 308
 309         /* Retrieve the correct rpc_client for the byte range */
 310         j = nfs4_fl_calc_j_index(lseg, offset);
 311         idx = nfs4_fl_calc_ds_index(lseg, j);
 312         ds = nfs4_fl_prepare_ds(lseg, idx);
 313         if (!ds) {
 314                 printk(KERN_ERR "%s: prepare_ds failed, use MDS\n", __func__);
 315                 set_bit(lo_fail_bit(IOMODE_RW), &lseg->pls_layout->plh_flags);
 316                 set_bit(lo_fail_bit(IOMODE_READ), &lseg->pls_layout->plh_flags);
 317                 return PNFS_NOT_ATTEMPTED;
 318         }
 319         dprintk("%s ino %lu sync %d req %Zu@%llu DS:%x:%hu\n", __func__,
 320                 data->inode->i_ino, sync, (size_t) data->args.count, offset,
 321                 ntohl(ds->ds_ip_addr), ntohs(ds->ds_port));
 322
 323         /* We can't handle commit to ds yet */
 324         if (!FILELAYOUT_LSEG(lseg)->commit_through_mds)
 325                 data->args.stable = NFS_FILE_SYNC;
 326
 327         data->write_done_cb = filelayout_write_done_cb;
 328         data->ds_clp = ds->ds_clp;
 329         fh = nfs4_fl_select_ds_fh(lseg, j);
 330         if (fh)
 331                 data->args.fh = fh;
 332         /*
 333          * Get the file offset on the dserver. Set the write offset to
 334          * this offset and save the original offset.
 335          */
 336         data->args.offset = filelayout_get_dserver_offset(lseg, offset);
 337         data->mds_offset = offset;
 338
 339         /* Perform an asynchronous write */
 340         status = nfs_initiate_write(data, ds->ds_clp->cl_rpcclient,
 341                                     &filelayout_write_call_ops, sync);
 342         BUG_ON(status != 0);
 343         return PNFS_ATTEMPTED;
 344 }
 345
 346 /*
 347  * filelayout_check_layout()
 348  *
 349  * Make sure layout segment parameters are sane WRT the device.
 350  * At this point no generic layer initialization of the lseg has occurred,
 351  * and nothing has been added to the layout_hdr cache.
 352  *
 353  */
 354 static int
 355 filelayout_check_layout(struct pnfs_layout_hdr *lo,
 356                         struct nfs4_filelayout_segment *fl,
 357                         struct nfs4_layoutget_res *lgr,
 358                         struct nfs4_deviceid *id)
 359 {
 360         struct nfs4_file_layout_dsaddr *dsaddr;
 361         int status = -EINVAL;
 362         struct nfs_server *nfss = NFS_SERVER(lo->plh_inode);
 363
 364         dprintk("--> %s\n", __func__);
 365
 366         if (fl->pattern_offset > lgr->range.offset) {
 367                 dprintk("%s pattern_offset %lld to large\n",
 368                                 __func__, fl->pattern_offset);
 369                 goto out;
 370         }
 371
 372         if (!fl->stripe_unit || fl->stripe_unit % PAGE_SIZE) {
 373                 dprintk("%s Invalid stripe unit (%u)\n",
 374                         __func__, fl->stripe_unit);
 375                 goto out;
 376         }
 377
 378         /* find and reference the deviceid */
 379         dsaddr = nfs4_fl_find_get_deviceid(id);
 380         if (dsaddr == NULL) {
 381                 dsaddr = get_device_info(lo->plh_inode, id);
 382                 if (dsaddr == NULL)
 383                         goto out;
 384         }
 385         fl->dsaddr = dsaddr;
 386
 387         if (fl->first_stripe_index < 0 ||
 388             fl->first_stripe_index >= dsaddr->stripe_count) {
 389                 dprintk("%s Bad first_stripe_index %d\n",
 390                                 __func__, fl->first_stripe_index);
 391                 goto out_put;
 392         }
 393
 394         if ((fl->stripe_type == STRIPE_SPARSE &&
 395             fl->num_fh > 1 && fl->num_fh != dsaddr->ds_num) ||
 396             (fl->stripe_type == STRIPE_DENSE &&
 397             fl->num_fh != dsaddr->stripe_count)) {
 398                 dprintk("%s num_fh %u not valid for given packing\n",
 399                         __func__, fl->num_fh);
 400                 goto out_put;
 401         }
 402
 403         if (fl->stripe_unit % nfss->rsize || fl->stripe_unit % nfss->wsize) {
 404                 dprintk("%s Stripe unit (%u) not aligned with rsize %u "
 405                         "wsize %u\n", __func__, fl->stripe_unit, nfss->rsize,
 406                         nfss->wsize);
 407         }
 408
 409         status = 0;
 410 out:
 411         dprintk("--> %s returns %d\n", __func__, status);
 412         return status;
 413 out_put:
 414         nfs4_fl_put_deviceid(dsaddr);
 415         goto out;
 416 }
 417
 418 static void filelayout_free_fh_array(struct nfs4_filelayout_segment *fl)
 419 {
 420         int i;
 421
 422         for (i = 0; i < fl->num_fh; i++) {
 423                 if (!fl->fh_array[i])
 424                         break;
 425                 kfree(fl->fh_array[i]);
 426         }
 427         kfree(fl->fh_array);
 428         fl->fh_array = NULL;
 429 }
 430
 431 static void
 432 _filelayout_free_lseg(struct nfs4_filelayout_segment *fl)
 433 {
 434         filelayout_free_fh_array(fl);
 435         kfree(fl);
 436 }
 437
 438 static int
 439 filelayout_decode_layout(struct pnfs_layout_hdr *flo,
 440                          struct nfs4_filelayout_segment *fl,
 441                          struct nfs4_layoutget_res *lgr,
 442                          struct nfs4_deviceid *id)
 443 {
 444         uint32_t *p = (uint32_t *)lgr->layout.buf;
 445         uint32_t nfl_util;
 446         int i;
 447
 448         dprintk("%s: set_layout_map Begin\n", __func__);
 449
 450         memcpy(id, p, sizeof(*id));
 451         p += XDR_QUADLEN(NFS4_DEVICEID4_SIZE);
 452         print_deviceid(id);
 453
 454         nfl_util = be32_to_cpup(p++);
 455         if (nfl_util & NFL4_UFLG_COMMIT_THRU_MDS)
 456                 fl->commit_through_mds = 1;
 457         if (nfl_util & NFL4_UFLG_DENSE)
 458                 fl->stripe_type = STRIPE_DENSE;
 459         else
 460                 fl->stripe_type = STRIPE_SPARSE;
 461         fl->stripe_unit = nfl_util & ~NFL4_UFLG_MASK;
 462
 463         fl->first_stripe_index = be32_to_cpup(p++);
 464         p = xdr_decode_hyper(p, &fl->pattern_offset);
 465         fl->num_fh = be32_to_cpup(p++);
 466
 467         dprintk("%s: nfl_util 0x%X num_fh %u fsi %u po %llu\n",
 468                 __func__, nfl_util, fl->num_fh, fl->first_stripe_index,
 469                 fl->pattern_offset);
 470
 471         fl->fh_array = kzalloc(fl->num_fh * sizeof(struct nfs_fh *),
 472                                GFP_KERNEL);
 473         if (!fl->fh_array)
 474                 return -ENOMEM;
 475
 476         for (i = 0; i < fl->num_fh; i++) {
 477                 /* Do we want to use a mempool here? */
 478                 fl->fh_array[i] = kmalloc(sizeof(struct nfs_fh), GFP_KERNEL);
 479                 if (!fl->fh_array[i]) {
 480                         filelayout_free_fh_array(fl);
 481                         return -ENOMEM;
 482                 }
 483                 fl->fh_array[i]->size = be32_to_cpup(p++);
 484                 if (sizeof(struct nfs_fh) < fl->fh_array[i]->size) {
 485                         printk(KERN_ERR "Too big fh %d received %d\n",
 486                                i, fl->fh_array[i]->size);
 487                         filelayout_free_fh_array(fl);
 488                         return -EIO;
 489                 }
 490                 memcpy(fl->fh_array[i]->data, p, fl->fh_array[i]->size);
 491                 p += XDR_QUADLEN(fl->fh_array[i]->size);
 492                 dprintk("DEBUG: %s: fh len %d\n", __func__,
 493                         fl->fh_array[i]->size);
 494         }
 495
 496         return 0;
 497 }
 498
 499 static struct pnfs_layout_segment *
 500 filelayout_alloc_lseg(struct pnfs_layout_hdr *layoutid,
 501                       struct nfs4_layoutget_res *lgr)
 502 {
 503         struct nfs4_filelayout_segment *fl;
 504         int rc;
 505         struct nfs4_deviceid id;
 506
 507         dprintk("--> %s\n", __func__);
 508         fl = kzalloc(sizeof(*fl), GFP_KERNEL);
 509         if (!fl)
 510                 return NULL;
 511
 512         rc = filelayout_decode_layout(layoutid, fl, lgr, &id);
 513         if (rc != 0 || filelayout_check_layout(layoutid, fl, lgr, &id)) {
 514                 _filelayout_free_lseg(fl);
 515                 return NULL;
 516         }
 517         return &fl->generic_hdr;
 518 }
 519
 520 static void
 521 filelayout_free_lseg(struct pnfs_layout_segment *lseg)
 522 {
 523         struct nfs4_filelayout_segment *fl = FILELAYOUT_LSEG(lseg);
 524
 525         dprintk("--> %s\n", __func__);
 526         nfs4_fl_put_deviceid(fl->dsaddr);
 527         _filelayout_free_lseg(fl);
 528 }
 529
 530 /*
 531  * filelayout_pg_test(). Called by nfs_can_coalesce_requests()
 532  *
 533  * return 1 :  coalesce page
 534  * return 0 :  don't coalesce page
 535  */
 536 int
 537 filelayout_pg_test(struct nfs_pageio_descriptor *pgio, struct nfs_page *prev,
 538                    struct nfs_page *req)
 539 {
 540         u64 p_stripe, r_stripe;
 541         u32 stripe_unit;
 542
 543         if (!pgio->pg_lseg)
 544                 return 1;
 545         p_stripe = (u64)prev->wb_index << PAGE_CACHE_SHIFT;
 546         r_stripe = (u64)req->wb_index << PAGE_CACHE_SHIFT;
 547         stripe_unit = FILELAYOUT_LSEG(pgio->pg_lseg)->stripe_unit;
 548
 549         do_div(p_stripe, stripe_unit);
 550         do_div(r_stripe, stripe_unit);
 551
 552         return (p_stripe == r_stripe);
 553 }
 554
 555 static struct pnfs_layoutdriver_type filelayout_type = {
 556         .id                     = LAYOUT_NFSV4_1_FILES,
 557         .name                   = "LAYOUT_NFSV4_1_FILES",
 558         .owner                  = THIS_MODULE,
 559         .alloc_lseg             = filelayout_alloc_lseg,
 560         .free_lseg              = filelayout_free_lseg,
 561         .pg_test                = filelayout_pg_test,
 562         .read_pagelist          = filelayout_read_pagelist,
 563         .write_pagelist         = filelayout_write_pagelist,
 564 };
 565
 566 static int __init nfs4filelayout_init(void)
 567 {
 568         printk(KERN_INFO "%s: NFSv4 File Layout Driver Registering...\n",
 569                __func__);
 570         return pnfs_register_layoutdriver(&filelayout_type);
 571 }
 572
 573 static void __exit nfs4filelayout_exit(void)
 574 {
 575         printk(KERN_INFO "%s: NFSv4 File Layout Driver Unregistering...\n",
 576                __func__);
 577         pnfs_unregister_layoutdriver(&filelayout_type);
 578 }
 579
 580 module_init(nfs4filelayout_init);
 581 module_exit(nfs4filelayout_exit);