linux/fs/nfs/flexfilelayout/flexfilelayout.c
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   1/*
   2 * Module for pnfs flexfile layout driver.
   3 *
   4 * Copyright (c) 2014, Primary Data, Inc. All rights reserved.
   5 *
   6 * Tao Peng <bergwolf@primarydata.com>
   7 */
   8
   9#include <linux/nfs_fs.h>
  10#include <linux/nfs_page.h>
  11#include <linux/module.h>
  12
  13#include <linux/sunrpc/metrics.h>
  14
  15#include "flexfilelayout.h"
  16#include "../nfs4session.h"
  17#include "../nfs4idmap.h"
  18#include "../internal.h"
  19#include "../delegation.h"
  20#include "../nfs4trace.h"
  21#include "../iostat.h"
  22#include "../nfs.h"
  23
  24#define NFSDBG_FACILITY         NFSDBG_PNFS_LD
  25
  26#define FF_LAYOUT_POLL_RETRY_MAX     (15*HZ)
  27
  28static struct pnfs_layout_hdr *
  29ff_layout_alloc_layout_hdr(struct inode *inode, gfp_t gfp_flags)
  30{
  31        struct nfs4_flexfile_layout *ffl;
  32
  33        ffl = kzalloc(sizeof(*ffl), gfp_flags);
  34        if (ffl) {
  35                INIT_LIST_HEAD(&ffl->error_list);
  36                return &ffl->generic_hdr;
  37        } else
  38                return NULL;
  39}
  40
  41static void
  42ff_layout_free_layout_hdr(struct pnfs_layout_hdr *lo)
  43{
  44        struct nfs4_ff_layout_ds_err *err, *n;
  45
  46        list_for_each_entry_safe(err, n, &FF_LAYOUT_FROM_HDR(lo)->error_list,
  47                                 list) {
  48                list_del(&err->list);
  49                kfree(err);
  50        }
  51        kfree(FF_LAYOUT_FROM_HDR(lo));
  52}
  53
  54static int decode_stateid(struct xdr_stream *xdr, nfs4_stateid *stateid)
  55{
  56        __be32 *p;
  57
  58        p = xdr_inline_decode(xdr, NFS4_STATEID_SIZE);
  59        if (unlikely(p == NULL))
  60                return -ENOBUFS;
  61        memcpy(stateid, p, NFS4_STATEID_SIZE);
  62        dprintk("%s: stateid id= [%x%x%x%x]\n", __func__,
  63                p[0], p[1], p[2], p[3]);
  64        return 0;
  65}
  66
  67static int decode_deviceid(struct xdr_stream *xdr, struct nfs4_deviceid *devid)
  68{
  69        __be32 *p;
  70
  71        p = xdr_inline_decode(xdr, NFS4_DEVICEID4_SIZE);
  72        if (unlikely(!p))
  73                return -ENOBUFS;
  74        memcpy(devid, p, NFS4_DEVICEID4_SIZE);
  75        nfs4_print_deviceid(devid);
  76        return 0;
  77}
  78
  79static int decode_nfs_fh(struct xdr_stream *xdr, struct nfs_fh *fh)
  80{
  81        __be32 *p;
  82
  83        p = xdr_inline_decode(xdr, 4);
  84        if (unlikely(!p))
  85                return -ENOBUFS;
  86        fh->size = be32_to_cpup(p++);
  87        if (fh->size > sizeof(struct nfs_fh)) {
  88                printk(KERN_ERR "NFS flexfiles: Too big fh received %d\n",
  89                       fh->size);
  90                return -EOVERFLOW;
  91        }
  92        /* fh.data */
  93        p = xdr_inline_decode(xdr, fh->size);
  94        if (unlikely(!p))
  95                return -ENOBUFS;
  96        memcpy(&fh->data, p, fh->size);
  97        dprintk("%s: fh len %d\n", __func__, fh->size);
  98
  99        return 0;
 100}
 101
 102/*
 103 * Currently only stringified uids and gids are accepted.
 104 * I.e., kerberos is not supported to the DSes, so no pricipals.
 105 *
 106 * That means that one common function will suffice, but when
 107 * principals are added, this should be split to accomodate
 108 * calls to both nfs_map_name_to_uid() and nfs_map_group_to_gid().
 109 */
 110static int
 111decode_name(struct xdr_stream *xdr, u32 *id)
 112{
 113        __be32 *p;
 114        int len;
 115
 116        /* opaque_length(4)*/
 117        p = xdr_inline_decode(xdr, 4);
 118        if (unlikely(!p))
 119                return -ENOBUFS;
 120        len = be32_to_cpup(p++);
 121        if (len < 0)
 122                return -EINVAL;
 123
 124        dprintk("%s: len %u\n", __func__, len);
 125
 126        /* opaque body */
 127        p = xdr_inline_decode(xdr, len);
 128        if (unlikely(!p))
 129                return -ENOBUFS;
 130
 131        if (!nfs_map_string_to_numeric((char *)p, len, id))
 132                return -EINVAL;
 133
 134        return 0;
 135}
 136
 137static void ff_layout_free_mirror_array(struct nfs4_ff_layout_segment *fls)
 138{
 139        int i;
 140
 141        if (fls->mirror_array) {
 142                for (i = 0; i < fls->mirror_array_cnt; i++) {
 143                        /* normally mirror_ds is freed in
 144                         * .free_deviceid_node but we still do it here
 145                         * for .alloc_lseg error path */
 146                        if (fls->mirror_array[i]) {
 147                                kfree(fls->mirror_array[i]->fh_versions);
 148                                nfs4_ff_layout_put_deviceid(fls->mirror_array[i]->mirror_ds);
 149                                kfree(fls->mirror_array[i]);
 150                        }
 151                }
 152                kfree(fls->mirror_array);
 153                fls->mirror_array = NULL;
 154        }
 155}
 156
 157static int ff_layout_check_layout(struct nfs4_layoutget_res *lgr)
 158{
 159        int ret = 0;
 160
 161        dprintk("--> %s\n", __func__);
 162
 163        /* FIXME: remove this check when layout segment support is added */
 164        if (lgr->range.offset != 0 ||
 165            lgr->range.length != NFS4_MAX_UINT64) {
 166                dprintk("%s Only whole file layouts supported. Use MDS i/o\n",
 167                        __func__);
 168                ret = -EINVAL;
 169        }
 170
 171        dprintk("--> %s returns %d\n", __func__, ret);
 172        return ret;
 173}
 174
 175static void _ff_layout_free_lseg(struct nfs4_ff_layout_segment *fls)
 176{
 177        if (fls) {
 178                ff_layout_free_mirror_array(fls);
 179                kfree(fls);
 180        }
 181}
 182
 183static void ff_layout_sort_mirrors(struct nfs4_ff_layout_segment *fls)
 184{
 185        struct nfs4_ff_layout_mirror *tmp;
 186        int i, j;
 187
 188        for (i = 0; i < fls->mirror_array_cnt - 1; i++) {
 189                for (j = i + 1; j < fls->mirror_array_cnt; j++)
 190                        if (fls->mirror_array[i]->efficiency <
 191                            fls->mirror_array[j]->efficiency) {
 192                                tmp = fls->mirror_array[i];
 193                                fls->mirror_array[i] = fls->mirror_array[j];
 194                                fls->mirror_array[j] = tmp;
 195                        }
 196        }
 197}
 198
 199static struct pnfs_layout_segment *
 200ff_layout_alloc_lseg(struct pnfs_layout_hdr *lh,
 201                     struct nfs4_layoutget_res *lgr,
 202                     gfp_t gfp_flags)
 203{
 204        struct pnfs_layout_segment *ret;
 205        struct nfs4_ff_layout_segment *fls = NULL;
 206        struct xdr_stream stream;
 207        struct xdr_buf buf;
 208        struct page *scratch;
 209        u64 stripe_unit;
 210        u32 mirror_array_cnt;
 211        __be32 *p;
 212        int i, rc;
 213
 214        dprintk("--> %s\n", __func__);
 215        scratch = alloc_page(gfp_flags);
 216        if (!scratch)
 217                return ERR_PTR(-ENOMEM);
 218
 219        xdr_init_decode_pages(&stream, &buf, lgr->layoutp->pages,
 220                              lgr->layoutp->len);
 221        xdr_set_scratch_buffer(&stream, page_address(scratch), PAGE_SIZE);
 222
 223        /* stripe unit and mirror_array_cnt */
 224        rc = -EIO;
 225        p = xdr_inline_decode(&stream, 8 + 4);
 226        if (!p)
 227                goto out_err_free;
 228
 229        p = xdr_decode_hyper(p, &stripe_unit);
 230        mirror_array_cnt = be32_to_cpup(p++);
 231        dprintk("%s: stripe_unit=%llu mirror_array_cnt=%u\n", __func__,
 232                stripe_unit, mirror_array_cnt);
 233
 234        if (mirror_array_cnt > NFS4_FLEXFILE_LAYOUT_MAX_MIRROR_CNT ||
 235            mirror_array_cnt == 0)
 236                goto out_err_free;
 237
 238        rc = -ENOMEM;
 239        fls = kzalloc(sizeof(*fls), gfp_flags);
 240        if (!fls)
 241                goto out_err_free;
 242
 243        fls->mirror_array_cnt = mirror_array_cnt;
 244        fls->stripe_unit = stripe_unit;
 245        fls->mirror_array = kcalloc(fls->mirror_array_cnt,
 246                                    sizeof(fls->mirror_array[0]), gfp_flags);
 247        if (fls->mirror_array == NULL)
 248                goto out_err_free;
 249
 250        for (i = 0; i < fls->mirror_array_cnt; i++) {
 251                struct nfs4_deviceid devid;
 252                struct nfs4_deviceid_node *idnode;
 253                u32 ds_count;
 254                u32 fh_count;
 255                int j;
 256
 257                rc = -EIO;
 258                p = xdr_inline_decode(&stream, 4);
 259                if (!p)
 260                        goto out_err_free;
 261                ds_count = be32_to_cpup(p);
 262
 263                /* FIXME: allow for striping? */
 264                if (ds_count != 1)
 265                        goto out_err_free;
 266
 267                fls->mirror_array[i] =
 268                        kzalloc(sizeof(struct nfs4_ff_layout_mirror),
 269                                gfp_flags);
 270                if (fls->mirror_array[i] == NULL) {
 271                        rc = -ENOMEM;
 272                        goto out_err_free;
 273                }
 274
 275                spin_lock_init(&fls->mirror_array[i]->lock);
 276                fls->mirror_array[i]->ds_count = ds_count;
 277
 278                /* deviceid */
 279                rc = decode_deviceid(&stream, &devid);
 280                if (rc)
 281                        goto out_err_free;
 282
 283                idnode = nfs4_find_get_deviceid(NFS_SERVER(lh->plh_inode),
 284                                                &devid, lh->plh_lc_cred,
 285                                                gfp_flags);
 286                /*
 287                 * upon success, mirror_ds is allocated by previous
 288                 * getdeviceinfo, or newly by .alloc_deviceid_node
 289                 * nfs4_find_get_deviceid failure is indeed getdeviceinfo falure
 290                 */
 291                if (idnode)
 292                        fls->mirror_array[i]->mirror_ds =
 293                                FF_LAYOUT_MIRROR_DS(idnode);
 294                else
 295                        goto out_err_free;
 296
 297                /* efficiency */
 298                rc = -EIO;
 299                p = xdr_inline_decode(&stream, 4);
 300                if (!p)
 301                        goto out_err_free;
 302                fls->mirror_array[i]->efficiency = be32_to_cpup(p);
 303
 304                /* stateid */
 305                rc = decode_stateid(&stream, &fls->mirror_array[i]->stateid);
 306                if (rc)
 307                        goto out_err_free;
 308
 309                /* fh */
 310                p = xdr_inline_decode(&stream, 4);
 311                if (!p)
 312                        goto out_err_free;
 313                fh_count = be32_to_cpup(p);
 314
 315                fls->mirror_array[i]->fh_versions =
 316                        kzalloc(fh_count * sizeof(struct nfs_fh),
 317                                gfp_flags);
 318                if (fls->mirror_array[i]->fh_versions == NULL) {
 319                        rc = -ENOMEM;
 320                        goto out_err_free;
 321                }
 322
 323                for (j = 0; j < fh_count; j++) {
 324                        rc = decode_nfs_fh(&stream,
 325                                           &fls->mirror_array[i]->fh_versions[j]);
 326                        if (rc)
 327                                goto out_err_free;
 328                }
 329
 330                fls->mirror_array[i]->fh_versions_cnt = fh_count;
 331
 332                /* user */
 333                rc = decode_name(&stream, &fls->mirror_array[i]->uid);
 334                if (rc)
 335                        goto out_err_free;
 336
 337                /* group */
 338                rc = decode_name(&stream, &fls->mirror_array[i]->gid);
 339                if (rc)
 340                        goto out_err_free;
 341
 342                dprintk("%s: uid %d gid %d\n", __func__,
 343                        fls->mirror_array[i]->uid,
 344                        fls->mirror_array[i]->gid);
 345        }
 346
 347        ff_layout_sort_mirrors(fls);
 348        rc = ff_layout_check_layout(lgr);
 349        if (rc)
 350                goto out_err_free;
 351
 352        ret = &fls->generic_hdr;
 353        dprintk("<-- %s (success)\n", __func__);
 354out_free_page:
 355        __free_page(scratch);
 356        return ret;
 357out_err_free:
 358        _ff_layout_free_lseg(fls);
 359        ret = ERR_PTR(rc);
 360        dprintk("<-- %s (%d)\n", __func__, rc);
 361        goto out_free_page;
 362}
 363
 364static bool ff_layout_has_rw_segments(struct pnfs_layout_hdr *layout)
 365{
 366        struct pnfs_layout_segment *lseg;
 367
 368        list_for_each_entry(lseg, &layout->plh_segs, pls_list)
 369                if (lseg->pls_range.iomode == IOMODE_RW)
 370                        return true;
 371
 372        return false;
 373}
 374
 375static void
 376ff_layout_free_lseg(struct pnfs_layout_segment *lseg)
 377{
 378        struct nfs4_ff_layout_segment *fls = FF_LAYOUT_LSEG(lseg);
 379        int i;
 380
 381        dprintk("--> %s\n", __func__);
 382
 383        for (i = 0; i < fls->mirror_array_cnt; i++) {
 384                if (fls->mirror_array[i]) {
 385                        nfs4_ff_layout_put_deviceid(fls->mirror_array[i]->mirror_ds);
 386                        fls->mirror_array[i]->mirror_ds = NULL;
 387                        if (fls->mirror_array[i]->cred) {
 388                                put_rpccred(fls->mirror_array[i]->cred);
 389                                fls->mirror_array[i]->cred = NULL;
 390                        }
 391                }
 392        }
 393
 394        if (lseg->pls_range.iomode == IOMODE_RW) {
 395                struct nfs4_flexfile_layout *ffl;
 396                struct inode *inode;
 397
 398                ffl = FF_LAYOUT_FROM_HDR(lseg->pls_layout);
 399                inode = ffl->generic_hdr.plh_inode;
 400                spin_lock(&inode->i_lock);
 401                if (!ff_layout_has_rw_segments(lseg->pls_layout)) {
 402                        ffl->commit_info.nbuckets = 0;
 403                        kfree(ffl->commit_info.buckets);
 404                        ffl->commit_info.buckets = NULL;
 405                }
 406                spin_unlock(&inode->i_lock);
 407        }
 408        _ff_layout_free_lseg(fls);
 409}
 410
 411/* Return 1 until we have multiple lsegs support */
 412static int
 413ff_layout_get_lseg_count(struct nfs4_ff_layout_segment *fls)
 414{
 415        return 1;
 416}
 417
 418static int
 419ff_layout_alloc_commit_info(struct pnfs_layout_segment *lseg,
 420                            struct nfs_commit_info *cinfo,
 421                            gfp_t gfp_flags)
 422{
 423        struct nfs4_ff_layout_segment *fls = FF_LAYOUT_LSEG(lseg);
 424        struct pnfs_commit_bucket *buckets;
 425        int size;
 426
 427        if (cinfo->ds->nbuckets != 0) {
 428                /* This assumes there is only one RW lseg per file.
 429                 * To support multiple lseg per file, we need to
 430                 * change struct pnfs_commit_bucket to allow dynamic
 431                 * increasing nbuckets.
 432                 */
 433                return 0;
 434        }
 435
 436        size = ff_layout_get_lseg_count(fls) * FF_LAYOUT_MIRROR_COUNT(lseg);
 437
 438        buckets = kcalloc(size, sizeof(struct pnfs_commit_bucket),
 439                          gfp_flags);
 440        if (!buckets)
 441                return -ENOMEM;
 442        else {
 443                int i;
 444
 445                spin_lock(cinfo->lock);
 446                if (cinfo->ds->nbuckets != 0)
 447                        kfree(buckets);
 448                else {
 449                        cinfo->ds->buckets = buckets;
 450                        cinfo->ds->nbuckets = size;
 451                        for (i = 0; i < size; i++) {
 452                                INIT_LIST_HEAD(&buckets[i].written);
 453                                INIT_LIST_HEAD(&buckets[i].committing);
 454                                /* mark direct verifier as unset */
 455                                buckets[i].direct_verf.committed =
 456                                        NFS_INVALID_STABLE_HOW;
 457                        }
 458                }
 459                spin_unlock(cinfo->lock);
 460                return 0;
 461        }
 462}
 463
 464static struct nfs4_pnfs_ds *
 465ff_layout_choose_best_ds_for_read(struct nfs_pageio_descriptor *pgio,
 466                                  int *best_idx)
 467{
 468        struct nfs4_ff_layout_segment *fls;
 469        struct nfs4_pnfs_ds *ds;
 470        int idx;
 471
 472        fls = FF_LAYOUT_LSEG(pgio->pg_lseg);
 473        /* mirrors are sorted by efficiency */
 474        for (idx = 0; idx < fls->mirror_array_cnt; idx++) {
 475                ds = nfs4_ff_layout_prepare_ds(pgio->pg_lseg, idx, false);
 476                if (ds) {
 477                        *best_idx = idx;
 478                        return ds;
 479                }
 480        }
 481
 482        return NULL;
 483}
 484
 485static void
 486ff_layout_pg_init_read(struct nfs_pageio_descriptor *pgio,
 487                        struct nfs_page *req)
 488{
 489        struct nfs_pgio_mirror *pgm;
 490        struct nfs4_ff_layout_mirror *mirror;
 491        struct nfs4_pnfs_ds *ds;
 492        int ds_idx;
 493
 494        /* Use full layout for now */
 495        if (!pgio->pg_lseg)
 496                pgio->pg_lseg = pnfs_update_layout(pgio->pg_inode,
 497                                                   req->wb_context,
 498                                                   0,
 499                                                   NFS4_MAX_UINT64,
 500                                                   IOMODE_READ,
 501                                                   GFP_KERNEL);
 502        /* If no lseg, fall back to read through mds */
 503        if (pgio->pg_lseg == NULL)
 504                goto out_mds;
 505
 506        ds = ff_layout_choose_best_ds_for_read(pgio, &ds_idx);
 507        if (!ds)
 508                goto out_mds;
 509        mirror = FF_LAYOUT_COMP(pgio->pg_lseg, ds_idx);
 510
 511        pgio->pg_mirror_idx = ds_idx;
 512
 513        /* read always uses only one mirror - idx 0 for pgio layer */
 514        pgm = &pgio->pg_mirrors[0];
 515        pgm->pg_bsize = mirror->mirror_ds->ds_versions[0].rsize;
 516
 517        return;
 518out_mds:
 519        pnfs_put_lseg(pgio->pg_lseg);
 520        pgio->pg_lseg = NULL;
 521        nfs_pageio_reset_read_mds(pgio);
 522}
 523
 524static void
 525ff_layout_pg_init_write(struct nfs_pageio_descriptor *pgio,
 526                        struct nfs_page *req)
 527{
 528        struct nfs4_ff_layout_mirror *mirror;
 529        struct nfs_pgio_mirror *pgm;
 530        struct nfs_commit_info cinfo;
 531        struct nfs4_pnfs_ds *ds;
 532        int i;
 533        int status;
 534
 535        if (!pgio->pg_lseg)
 536                pgio->pg_lseg = pnfs_update_layout(pgio->pg_inode,
 537                                                   req->wb_context,
 538                                                   0,
 539                                                   NFS4_MAX_UINT64,
 540                                                   IOMODE_RW,
 541                                                   GFP_NOFS);
 542        /* If no lseg, fall back to write through mds */
 543        if (pgio->pg_lseg == NULL)
 544                goto out_mds;
 545
 546        nfs_init_cinfo(&cinfo, pgio->pg_inode, pgio->pg_dreq);
 547        status = ff_layout_alloc_commit_info(pgio->pg_lseg, &cinfo, GFP_NOFS);
 548        if (status < 0)
 549                goto out_mds;
 550
 551        /* Use a direct mapping of ds_idx to pgio mirror_idx */
 552        if (WARN_ON_ONCE(pgio->pg_mirror_count !=
 553            FF_LAYOUT_MIRROR_COUNT(pgio->pg_lseg)))
 554                goto out_mds;
 555
 556        for (i = 0; i < pgio->pg_mirror_count; i++) {
 557                ds = nfs4_ff_layout_prepare_ds(pgio->pg_lseg, i, true);
 558                if (!ds)
 559                        goto out_mds;
 560                pgm = &pgio->pg_mirrors[i];
 561                mirror = FF_LAYOUT_COMP(pgio->pg_lseg, i);
 562                pgm->pg_bsize = mirror->mirror_ds->ds_versions[0].wsize;
 563        }
 564
 565        return;
 566
 567out_mds:
 568        pnfs_put_lseg(pgio->pg_lseg);
 569        pgio->pg_lseg = NULL;
 570        nfs_pageio_reset_write_mds(pgio);
 571}
 572
 573static unsigned int
 574ff_layout_pg_get_mirror_count_write(struct nfs_pageio_descriptor *pgio,
 575                                    struct nfs_page *req)
 576{
 577        if (!pgio->pg_lseg)
 578                pgio->pg_lseg = pnfs_update_layout(pgio->pg_inode,
 579                                                   req->wb_context,
 580                                                   0,
 581                                                   NFS4_MAX_UINT64,
 582                                                   IOMODE_RW,
 583                                                   GFP_NOFS);
 584        if (pgio->pg_lseg)
 585                return FF_LAYOUT_MIRROR_COUNT(pgio->pg_lseg);
 586
 587        /* no lseg means that pnfs is not in use, so no mirroring here */
 588        pnfs_put_lseg(pgio->pg_lseg);
 589        pgio->pg_lseg = NULL;
 590        nfs_pageio_reset_write_mds(pgio);
 591        return 1;
 592}
 593
 594static const struct nfs_pageio_ops ff_layout_pg_read_ops = {
 595        .pg_init = ff_layout_pg_init_read,
 596        .pg_test = pnfs_generic_pg_test,
 597        .pg_doio = pnfs_generic_pg_readpages,
 598        .pg_cleanup = pnfs_generic_pg_cleanup,
 599};
 600
 601static const struct nfs_pageio_ops ff_layout_pg_write_ops = {
 602        .pg_init = ff_layout_pg_init_write,
 603        .pg_test = pnfs_generic_pg_test,
 604        .pg_doio = pnfs_generic_pg_writepages,
 605        .pg_get_mirror_count = ff_layout_pg_get_mirror_count_write,
 606        .pg_cleanup = pnfs_generic_pg_cleanup,
 607};
 608
 609static void ff_layout_reset_write(struct nfs_pgio_header *hdr, bool retry_pnfs)
 610{
 611        struct rpc_task *task = &hdr->task;
 612
 613        pnfs_layoutcommit_inode(hdr->inode, false);
 614
 615        if (retry_pnfs) {
 616                dprintk("%s Reset task %5u for i/o through pNFS "
 617                        "(req %s/%llu, %u bytes @ offset %llu)\n", __func__,
 618                        hdr->task.tk_pid,
 619                        hdr->inode->i_sb->s_id,
 620                        (unsigned long long)NFS_FILEID(hdr->inode),
 621                        hdr->args.count,
 622                        (unsigned long long)hdr->args.offset);
 623
 624                if (!hdr->dreq) {
 625                        struct nfs_open_context *ctx;
 626
 627                        ctx = nfs_list_entry(hdr->pages.next)->wb_context;
 628                        set_bit(NFS_CONTEXT_RESEND_WRITES, &ctx->flags);
 629                        hdr->completion_ops->error_cleanup(&hdr->pages);
 630                } else {
 631                        nfs_direct_set_resched_writes(hdr->dreq);
 632                        /* fake unstable write to let common nfs resend pages */
 633                        hdr->verf.committed = NFS_UNSTABLE;
 634                        hdr->good_bytes = 0;
 635                }
 636                return;
 637        }
 638
 639        if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags)) {
 640                dprintk("%s Reset task %5u for i/o through MDS "
 641                        "(req %s/%llu, %u bytes @ offset %llu)\n", __func__,
 642                        hdr->task.tk_pid,
 643                        hdr->inode->i_sb->s_id,
 644                        (unsigned long long)NFS_FILEID(hdr->inode),
 645                        hdr->args.count,
 646                        (unsigned long long)hdr->args.offset);
 647
 648                task->tk_status = pnfs_write_done_resend_to_mds(hdr);
 649        }
 650}
 651
 652static void ff_layout_reset_read(struct nfs_pgio_header *hdr)
 653{
 654        struct rpc_task *task = &hdr->task;
 655
 656        pnfs_layoutcommit_inode(hdr->inode, false);
 657
 658        if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags)) {
 659                dprintk("%s Reset task %5u for i/o through MDS "
 660                        "(req %s/%llu, %u bytes @ offset %llu)\n", __func__,
 661                        hdr->task.tk_pid,
 662                        hdr->inode->i_sb->s_id,
 663                        (unsigned long long)NFS_FILEID(hdr->inode),
 664                        hdr->args.count,
 665                        (unsigned long long)hdr->args.offset);
 666
 667                task->tk_status = pnfs_read_done_resend_to_mds(hdr);
 668        }
 669}
 670
 671static int ff_layout_async_handle_error_v4(struct rpc_task *task,
 672                                           struct nfs4_state *state,
 673                                           struct nfs_client *clp,
 674                                           struct pnfs_layout_segment *lseg,
 675                                           int idx)
 676{
 677        struct pnfs_layout_hdr *lo = lseg->pls_layout;
 678        struct inode *inode = lo->plh_inode;
 679        struct nfs_server *mds_server = NFS_SERVER(inode);
 680
 681        struct nfs4_deviceid_node *devid = FF_LAYOUT_DEVID_NODE(lseg, idx);
 682        struct nfs_client *mds_client = mds_server->nfs_client;
 683        struct nfs4_slot_table *tbl = &clp->cl_session->fc_slot_table;
 684
 685        if (task->tk_status >= 0)
 686                return 0;
 687
 688        switch (task->tk_status) {
 689        /* MDS state errors */
 690        case -NFS4ERR_DELEG_REVOKED:
 691        case -NFS4ERR_ADMIN_REVOKED:
 692        case -NFS4ERR_BAD_STATEID:
 693                if (state == NULL)
 694                        break;
 695                nfs_remove_bad_delegation(state->inode);
 696        case -NFS4ERR_OPENMODE:
 697                if (state == NULL)
 698                        break;
 699                if (nfs4_schedule_stateid_recovery(mds_server, state) < 0)
 700                        goto out_bad_stateid;
 701                goto wait_on_recovery;
 702        case -NFS4ERR_EXPIRED:
 703                if (state != NULL) {
 704                        if (nfs4_schedule_stateid_recovery(mds_server, state) < 0)
 705                                goto out_bad_stateid;
 706                }
 707                nfs4_schedule_lease_recovery(mds_client);
 708                goto wait_on_recovery;
 709        /* DS session errors */
 710        case -NFS4ERR_BADSESSION:
 711        case -NFS4ERR_BADSLOT:
 712        case -NFS4ERR_BAD_HIGH_SLOT:
 713        case -NFS4ERR_DEADSESSION:
 714        case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
 715        case -NFS4ERR_SEQ_FALSE_RETRY:
 716        case -NFS4ERR_SEQ_MISORDERED:
 717                dprintk("%s ERROR %d, Reset session. Exchangeid "
 718                        "flags 0x%x\n", __func__, task->tk_status,
 719                        clp->cl_exchange_flags);
 720                nfs4_schedule_session_recovery(clp->cl_session, task->tk_status);
 721                break;
 722        case -NFS4ERR_DELAY:
 723        case -NFS4ERR_GRACE:
 724                rpc_delay(task, FF_LAYOUT_POLL_RETRY_MAX);
 725                break;
 726        case -NFS4ERR_RETRY_UNCACHED_REP:
 727                break;
 728        /* Invalidate Layout errors */
 729        case -NFS4ERR_PNFS_NO_LAYOUT:
 730        case -ESTALE:           /* mapped NFS4ERR_STALE */
 731        case -EBADHANDLE:       /* mapped NFS4ERR_BADHANDLE */
 732        case -EISDIR:           /* mapped NFS4ERR_ISDIR */
 733        case -NFS4ERR_FHEXPIRED:
 734        case -NFS4ERR_WRONG_TYPE:
 735                dprintk("%s Invalid layout error %d\n", __func__,
 736                        task->tk_status);
 737                /*
 738                 * Destroy layout so new i/o will get a new layout.
 739                 * Layout will not be destroyed until all current lseg
 740                 * references are put. Mark layout as invalid to resend failed
 741                 * i/o and all i/o waiting on the slot table to the MDS until
 742                 * layout is destroyed and a new valid layout is obtained.
 743                 */
 744                pnfs_destroy_layout(NFS_I(inode));
 745                rpc_wake_up(&tbl->slot_tbl_waitq);
 746                goto reset;
 747        /* RPC connection errors */
 748        case -ECONNREFUSED:
 749        case -EHOSTDOWN:
 750        case -EHOSTUNREACH:
 751        case -ENETUNREACH:
 752        case -EIO:
 753        case -ETIMEDOUT:
 754        case -EPIPE:
 755                dprintk("%s DS connection error %d\n", __func__,
 756                        task->tk_status);
 757                nfs4_mark_deviceid_unavailable(devid);
 758                rpc_wake_up(&tbl->slot_tbl_waitq);
 759                /* fall through */
 760        default:
 761                if (ff_layout_has_available_ds(lseg))
 762                        return -NFS4ERR_RESET_TO_PNFS;
 763reset:
 764                dprintk("%s Retry through MDS. Error %d\n", __func__,
 765                        task->tk_status);
 766                return -NFS4ERR_RESET_TO_MDS;
 767        }
 768out:
 769        task->tk_status = 0;
 770        return -EAGAIN;
 771out_bad_stateid:
 772        task->tk_status = -EIO;
 773        return 0;
 774wait_on_recovery:
 775        rpc_sleep_on(&mds_client->cl_rpcwaitq, task, NULL);
 776        if (test_bit(NFS4CLNT_MANAGER_RUNNING, &mds_client->cl_state) == 0)
 777                rpc_wake_up_queued_task(&mds_client->cl_rpcwaitq, task);
 778        goto out;
 779}
 780
 781/* Retry all errors through either pNFS or MDS except for -EJUKEBOX */
 782static int ff_layout_async_handle_error_v3(struct rpc_task *task,
 783                                           struct pnfs_layout_segment *lseg,
 784                                           int idx)
 785{
 786        struct nfs4_deviceid_node *devid = FF_LAYOUT_DEVID_NODE(lseg, idx);
 787
 788        if (task->tk_status >= 0)
 789                return 0;
 790
 791        if (task->tk_status != -EJUKEBOX) {
 792                dprintk("%s DS connection error %d\n", __func__,
 793                        task->tk_status);
 794                nfs4_mark_deviceid_unavailable(devid);
 795                if (ff_layout_has_available_ds(lseg))
 796                        return -NFS4ERR_RESET_TO_PNFS;
 797                else
 798                        return -NFS4ERR_RESET_TO_MDS;
 799        }
 800
 801        if (task->tk_status == -EJUKEBOX)
 802                nfs_inc_stats(lseg->pls_layout->plh_inode, NFSIOS_DELAY);
 803        task->tk_status = 0;
 804        rpc_restart_call(task);
 805        rpc_delay(task, NFS_JUKEBOX_RETRY_TIME);
 806        return -EAGAIN;
 807}
 808
 809static int ff_layout_async_handle_error(struct rpc_task *task,
 810                                        struct nfs4_state *state,
 811                                        struct nfs_client *clp,
 812                                        struct pnfs_layout_segment *lseg,
 813                                        int idx)
 814{
 815        int vers = clp->cl_nfs_mod->rpc_vers->number;
 816
 817        switch (vers) {
 818        case 3:
 819                return ff_layout_async_handle_error_v3(task, lseg, idx);
 820        case 4:
 821                return ff_layout_async_handle_error_v4(task, state, clp,
 822                                                       lseg, idx);
 823        default:
 824                /* should never happen */
 825                WARN_ON_ONCE(1);
 826                return 0;
 827        }
 828}
 829
 830static void ff_layout_io_track_ds_error(struct pnfs_layout_segment *lseg,
 831                                        int idx, u64 offset, u64 length,
 832                                        u32 status, int opnum)
 833{
 834        struct nfs4_ff_layout_mirror *mirror;
 835        int err;
 836
 837        mirror = FF_LAYOUT_COMP(lseg, idx);
 838        err = ff_layout_track_ds_error(FF_LAYOUT_FROM_HDR(lseg->pls_layout),
 839                                       mirror, offset, length, status, opnum,
 840                                       GFP_NOIO);
 841        dprintk("%s: err %d op %d status %u\n", __func__, err, opnum, status);
 842}
 843
 844/* NFS_PROTO call done callback routines */
 845
 846static int ff_layout_read_done_cb(struct rpc_task *task,
 847                                struct nfs_pgio_header *hdr)
 848{
 849        struct inode *inode;
 850        int err;
 851
 852        trace_nfs4_pnfs_read(hdr, task->tk_status);
 853        if (task->tk_status == -ETIMEDOUT && !hdr->res.op_status)
 854                hdr->res.op_status = NFS4ERR_NXIO;
 855        if (task->tk_status < 0 && hdr->res.op_status)
 856                ff_layout_io_track_ds_error(hdr->lseg, hdr->pgio_mirror_idx,
 857                                            hdr->args.offset, hdr->args.count,
 858                                            hdr->res.op_status, OP_READ);
 859        err = ff_layout_async_handle_error(task, hdr->args.context->state,
 860                                           hdr->ds_clp, hdr->lseg,
 861                                           hdr->pgio_mirror_idx);
 862
 863        switch (err) {
 864        case -NFS4ERR_RESET_TO_PNFS:
 865                set_bit(NFS_LAYOUT_RETURN_BEFORE_CLOSE,
 866                        &hdr->lseg->pls_layout->plh_flags);
 867                pnfs_read_resend_pnfs(hdr);
 868                return task->tk_status;
 869        case -NFS4ERR_RESET_TO_MDS:
 870                inode = hdr->lseg->pls_layout->plh_inode;
 871                pnfs_error_mark_layout_for_return(inode, hdr->lseg);
 872                ff_layout_reset_read(hdr);
 873                return task->tk_status;
 874        case -EAGAIN:
 875                rpc_restart_call_prepare(task);
 876                return -EAGAIN;
 877        }
 878
 879        return 0;
 880}
 881
 882/*
 883 * We reference the rpc_cred of the first WRITE that triggers the need for
 884 * a LAYOUTCOMMIT, and use it to send the layoutcommit compound.
 885 * rfc5661 is not clear about which credential should be used.
 886 *
 887 * Flexlayout client should treat DS replied FILE_SYNC as DATA_SYNC, so
 888 * to follow http://www.rfc-editor.org/errata_search.php?rfc=5661&eid=2751
 889 * we always send layoutcommit after DS writes.
 890 */
 891static void
 892ff_layout_set_layoutcommit(struct nfs_pgio_header *hdr)
 893{
 894        pnfs_set_layoutcommit(hdr->inode, hdr->lseg,
 895                        hdr->mds_offset + hdr->res.count);
 896        dprintk("%s inode %lu pls_end_pos %lu\n", __func__, hdr->inode->i_ino,
 897                (unsigned long) NFS_I(hdr->inode)->layout->plh_lwb);
 898}
 899
 900static bool
 901ff_layout_reset_to_mds(struct pnfs_layout_segment *lseg, int idx)
 902{
 903        /* No mirroring for now */
 904        struct nfs4_deviceid_node *node = FF_LAYOUT_DEVID_NODE(lseg, idx);
 905
 906        return ff_layout_test_devid_unavailable(node);
 907}
 908
 909static int ff_layout_read_prepare_common(struct rpc_task *task,
 910                                         struct nfs_pgio_header *hdr)
 911{
 912        if (unlikely(test_bit(NFS_CONTEXT_BAD, &hdr->args.context->flags))) {
 913                rpc_exit(task, -EIO);
 914                return -EIO;
 915        }
 916        if (ff_layout_reset_to_mds(hdr->lseg, hdr->pgio_mirror_idx)) {
 917                dprintk("%s task %u reset io to MDS\n", __func__, task->tk_pid);
 918                if (ff_layout_has_available_ds(hdr->lseg))
 919                        pnfs_read_resend_pnfs(hdr);
 920                else
 921                        ff_layout_reset_read(hdr);
 922                rpc_exit(task, 0);
 923                return -EAGAIN;
 924        }
 925        hdr->pgio_done_cb = ff_layout_read_done_cb;
 926
 927        return 0;
 928}
 929
 930/*
 931 * Call ops for the async read/write cases
 932 * In the case of dense layouts, the offset needs to be reset to its
 933 * original value.
 934 */
 935static void ff_layout_read_prepare_v3(struct rpc_task *task, void *data)
 936{
 937        struct nfs_pgio_header *hdr = data;
 938
 939        if (ff_layout_read_prepare_common(task, hdr))
 940                return;
 941
 942        rpc_call_start(task);
 943}
 944
 945static int ff_layout_setup_sequence(struct nfs_client *ds_clp,
 946                                    struct nfs4_sequence_args *args,
 947                                    struct nfs4_sequence_res *res,
 948                                    struct rpc_task *task)
 949{
 950        if (ds_clp->cl_session)
 951                return nfs41_setup_sequence(ds_clp->cl_session,
 952                                           args,
 953                                           res,
 954                                           task);
 955        return nfs40_setup_sequence(ds_clp->cl_slot_tbl,
 956                                   args,
 957                                   res,
 958                                   task);
 959}
 960
 961static void ff_layout_read_prepare_v4(struct rpc_task *task, void *data)
 962{
 963        struct nfs_pgio_header *hdr = data;
 964
 965        if (ff_layout_read_prepare_common(task, hdr))
 966                return;
 967
 968        if (ff_layout_setup_sequence(hdr->ds_clp,
 969                                     &hdr->args.seq_args,
 970                                     &hdr->res.seq_res,
 971                                     task))
 972                return;
 973
 974        if (nfs4_set_rw_stateid(&hdr->args.stateid, hdr->args.context,
 975                        hdr->args.lock_context, FMODE_READ) == -EIO)
 976                rpc_exit(task, -EIO); /* lost lock, terminate I/O */
 977}
 978
 979static void ff_layout_read_call_done(struct rpc_task *task, void *data)
 980{
 981        struct nfs_pgio_header *hdr = data;
 982
 983        dprintk("--> %s task->tk_status %d\n", __func__, task->tk_status);
 984
 985        if (test_bit(NFS_IOHDR_REDO, &hdr->flags) &&
 986            task->tk_status == 0) {
 987                nfs4_sequence_done(task, &hdr->res.seq_res);
 988                return;
 989        }
 990
 991        /* Note this may cause RPC to be resent */
 992        hdr->mds_ops->rpc_call_done(task, hdr);
 993}
 994
 995static void ff_layout_read_count_stats(struct rpc_task *task, void *data)
 996{
 997        struct nfs_pgio_header *hdr = data;
 998
 999        rpc_count_iostats_metrics(task,
1000            &NFS_CLIENT(hdr->inode)->cl_metrics[NFSPROC4_CLNT_READ]);
1001}
1002
1003static int ff_layout_write_done_cb(struct rpc_task *task,
1004                                struct nfs_pgio_header *hdr)
1005{
1006        struct inode *inode;
1007        int err;
1008
1009        trace_nfs4_pnfs_write(hdr, task->tk_status);
1010        if (task->tk_status == -ETIMEDOUT && !hdr->res.op_status)
1011                hdr->res.op_status = NFS4ERR_NXIO;
1012        if (task->tk_status < 0 && hdr->res.op_status)
1013                ff_layout_io_track_ds_error(hdr->lseg, hdr->pgio_mirror_idx,
1014                                            hdr->args.offset, hdr->args.count,
1015                                            hdr->res.op_status, OP_WRITE);
1016        err = ff_layout_async_handle_error(task, hdr->args.context->state,
1017                                           hdr->ds_clp, hdr->lseg,
1018                                           hdr->pgio_mirror_idx);
1019
1020        switch (err) {
1021        case -NFS4ERR_RESET_TO_PNFS:
1022        case -NFS4ERR_RESET_TO_MDS:
1023                inode = hdr->lseg->pls_layout->plh_inode;
1024                pnfs_error_mark_layout_for_return(inode, hdr->lseg);
1025                if (err == -NFS4ERR_RESET_TO_PNFS) {
1026                        pnfs_set_retry_layoutget(hdr->lseg->pls_layout);
1027                        ff_layout_reset_write(hdr, true);
1028                } else {
1029                        pnfs_clear_retry_layoutget(hdr->lseg->pls_layout);
1030                        ff_layout_reset_write(hdr, false);
1031                }
1032                return task->tk_status;
1033        case -EAGAIN:
1034                rpc_restart_call_prepare(task);
1035                return -EAGAIN;
1036        }
1037
1038        if (hdr->res.verf->committed == NFS_FILE_SYNC ||
1039            hdr->res.verf->committed == NFS_DATA_SYNC)
1040                ff_layout_set_layoutcommit(hdr);
1041
1042        return 0;
1043}
1044
1045static int ff_layout_commit_done_cb(struct rpc_task *task,
1046                                     struct nfs_commit_data *data)
1047{
1048        struct inode *inode;
1049        int err;
1050
1051        trace_nfs4_pnfs_commit_ds(data, task->tk_status);
1052        if (task->tk_status == -ETIMEDOUT && !data->res.op_status)
1053                data->res.op_status = NFS4ERR_NXIO;
1054        if (task->tk_status < 0 && data->res.op_status)
1055                ff_layout_io_track_ds_error(data->lseg, data->ds_commit_index,
1056                                            data->args.offset, data->args.count,
1057                                            data->res.op_status, OP_COMMIT);
1058        err = ff_layout_async_handle_error(task, NULL, data->ds_clp,
1059                                           data->lseg, data->ds_commit_index);
1060
1061        switch (err) {
1062        case -NFS4ERR_RESET_TO_PNFS:
1063        case -NFS4ERR_RESET_TO_MDS:
1064                inode = data->lseg->pls_layout->plh_inode;
1065                pnfs_error_mark_layout_for_return(inode, data->lseg);
1066                if (err == -NFS4ERR_RESET_TO_PNFS)
1067                        pnfs_set_retry_layoutget(data->lseg->pls_layout);
1068                else
1069                        pnfs_clear_retry_layoutget(data->lseg->pls_layout);
1070                pnfs_generic_prepare_to_resend_writes(data);
1071                return -EAGAIN;
1072        case -EAGAIN:
1073                rpc_restart_call_prepare(task);
1074                return -EAGAIN;
1075        }
1076
1077        if (data->verf.committed == NFS_UNSTABLE)
1078                pnfs_set_layoutcommit(data->inode, data->lseg, data->lwb);
1079
1080        return 0;
1081}
1082
1083static int ff_layout_write_prepare_common(struct rpc_task *task,
1084                                          struct nfs_pgio_header *hdr)
1085{
1086        if (unlikely(test_bit(NFS_CONTEXT_BAD, &hdr->args.context->flags))) {
1087                rpc_exit(task, -EIO);
1088                return -EIO;
1089        }
1090
1091        if (ff_layout_reset_to_mds(hdr->lseg, hdr->pgio_mirror_idx)) {
1092                bool retry_pnfs;
1093
1094                retry_pnfs = ff_layout_has_available_ds(hdr->lseg);
1095                dprintk("%s task %u reset io to %s\n", __func__,
1096                        task->tk_pid, retry_pnfs ? "pNFS" : "MDS");
1097                ff_layout_reset_write(hdr, retry_pnfs);
1098                rpc_exit(task, 0);
1099                return -EAGAIN;
1100        }
1101
1102        return 0;
1103}
1104
1105static void ff_layout_write_prepare_v3(struct rpc_task *task, void *data)
1106{
1107        struct nfs_pgio_header *hdr = data;
1108
1109        if (ff_layout_write_prepare_common(task, hdr))
1110                return;
1111
1112        rpc_call_start(task);
1113}
1114
1115static void ff_layout_write_prepare_v4(struct rpc_task *task, void *data)
1116{
1117        struct nfs_pgio_header *hdr = data;
1118
1119        if (ff_layout_write_prepare_common(task, hdr))
1120                return;
1121
1122        if (ff_layout_setup_sequence(hdr->ds_clp,
1123                                     &hdr->args.seq_args,
1124                                     &hdr->res.seq_res,
1125                                     task))
1126                return;
1127
1128        if (nfs4_set_rw_stateid(&hdr->args.stateid, hdr->args.context,
1129                        hdr->args.lock_context, FMODE_WRITE) == -EIO)
1130                rpc_exit(task, -EIO); /* lost lock, terminate I/O */
1131}
1132
1133static void ff_layout_write_call_done(struct rpc_task *task, void *data)
1134{
1135        struct nfs_pgio_header *hdr = data;
1136
1137        if (test_bit(NFS_IOHDR_REDO, &hdr->flags) &&
1138            task->tk_status == 0) {
1139                nfs4_sequence_done(task, &hdr->res.seq_res);
1140                return;
1141        }
1142
1143        /* Note this may cause RPC to be resent */
1144        hdr->mds_ops->rpc_call_done(task, hdr);
1145}
1146
1147static void ff_layout_write_count_stats(struct rpc_task *task, void *data)
1148{
1149        struct nfs_pgio_header *hdr = data;
1150
1151        rpc_count_iostats_metrics(task,
1152            &NFS_CLIENT(hdr->inode)->cl_metrics[NFSPROC4_CLNT_WRITE]);
1153}
1154
1155static void ff_layout_commit_prepare_v3(struct rpc_task *task, void *data)
1156{
1157        rpc_call_start(task);
1158}
1159
1160static void ff_layout_commit_prepare_v4(struct rpc_task *task, void *data)
1161{
1162        struct nfs_commit_data *wdata = data;
1163
1164        ff_layout_setup_sequence(wdata->ds_clp,
1165                                 &wdata->args.seq_args,
1166                                 &wdata->res.seq_res,
1167                                 task);
1168}
1169
1170static void ff_layout_commit_count_stats(struct rpc_task *task, void *data)
1171{
1172        struct nfs_commit_data *cdata = data;
1173
1174        rpc_count_iostats_metrics(task,
1175            &NFS_CLIENT(cdata->inode)->cl_metrics[NFSPROC4_CLNT_COMMIT]);
1176}
1177
1178static const struct rpc_call_ops ff_layout_read_call_ops_v3 = {
1179        .rpc_call_prepare = ff_layout_read_prepare_v3,
1180        .rpc_call_done = ff_layout_read_call_done,
1181        .rpc_count_stats = ff_layout_read_count_stats,
1182        .rpc_release = pnfs_generic_rw_release,
1183};
1184
1185static const struct rpc_call_ops ff_layout_read_call_ops_v4 = {
1186        .rpc_call_prepare = ff_layout_read_prepare_v4,
1187        .rpc_call_done = ff_layout_read_call_done,
1188        .rpc_count_stats = ff_layout_read_count_stats,
1189        .rpc_release = pnfs_generic_rw_release,
1190};
1191
1192static const struct rpc_call_ops ff_layout_write_call_ops_v3 = {
1193        .rpc_call_prepare = ff_layout_write_prepare_v3,
1194        .rpc_call_done = ff_layout_write_call_done,
1195        .rpc_count_stats = ff_layout_write_count_stats,
1196        .rpc_release = pnfs_generic_rw_release,
1197};
1198
1199static const struct rpc_call_ops ff_layout_write_call_ops_v4 = {
1200        .rpc_call_prepare = ff_layout_write_prepare_v4,
1201        .rpc_call_done = ff_layout_write_call_done,
1202        .rpc_count_stats = ff_layout_write_count_stats,
1203        .rpc_release = pnfs_generic_rw_release,
1204};
1205
1206static const struct rpc_call_ops ff_layout_commit_call_ops_v3 = {
1207        .rpc_call_prepare = ff_layout_commit_prepare_v3,
1208        .rpc_call_done = pnfs_generic_write_commit_done,
1209        .rpc_count_stats = ff_layout_commit_count_stats,
1210        .rpc_release = pnfs_generic_commit_release,
1211};
1212
1213static const struct rpc_call_ops ff_layout_commit_call_ops_v4 = {
1214        .rpc_call_prepare = ff_layout_commit_prepare_v4,
1215        .rpc_call_done = pnfs_generic_write_commit_done,
1216        .rpc_count_stats = ff_layout_commit_count_stats,
1217        .rpc_release = pnfs_generic_commit_release,
1218};
1219
1220static enum pnfs_try_status
1221ff_layout_read_pagelist(struct nfs_pgio_header *hdr)
1222{
1223        struct pnfs_layout_segment *lseg = hdr->lseg;
1224        struct nfs4_pnfs_ds *ds;
1225        struct rpc_clnt *ds_clnt;
1226        struct rpc_cred *ds_cred;
1227        loff_t offset = hdr->args.offset;
1228        u32 idx = hdr->pgio_mirror_idx;
1229        int vers;
1230        struct nfs_fh *fh;
1231
1232        dprintk("--> %s ino %lu pgbase %u req %Zu@%llu\n",
1233                __func__, hdr->inode->i_ino,
1234                hdr->args.pgbase, (size_t)hdr->args.count, offset);
1235
1236        ds = nfs4_ff_layout_prepare_ds(lseg, idx, false);
1237        if (!ds)
1238                goto out_failed;
1239
1240        ds_clnt = nfs4_ff_find_or_create_ds_client(lseg, idx, ds->ds_clp,
1241                                                   hdr->inode);
1242        if (IS_ERR(ds_clnt))
1243                goto out_failed;
1244
1245        ds_cred = ff_layout_get_ds_cred(lseg, idx, hdr->cred);
1246        if (IS_ERR(ds_cred))
1247                goto out_failed;
1248
1249        vers = nfs4_ff_layout_ds_version(lseg, idx);
1250
1251        dprintk("%s USE DS: %s cl_count %d vers %d\n", __func__,
1252                ds->ds_remotestr, atomic_read(&ds->ds_clp->cl_count), vers);
1253
1254        atomic_inc(&ds->ds_clp->cl_count);
1255        hdr->ds_clp = ds->ds_clp;
1256        fh = nfs4_ff_layout_select_ds_fh(lseg, idx);
1257        if (fh)
1258                hdr->args.fh = fh;
1259
1260        /*
1261         * Note that if we ever decide to split across DSes,
1262         * then we may need to handle dense-like offsets.
1263         */
1264        hdr->args.offset = offset;
1265        hdr->mds_offset = offset;
1266
1267        /* Perform an asynchronous read to ds */
1268        nfs_initiate_pgio(ds_clnt, hdr, ds_cred, ds->ds_clp->rpc_ops,
1269                          vers == 3 ? &ff_layout_read_call_ops_v3 :
1270                                      &ff_layout_read_call_ops_v4,
1271                          0, RPC_TASK_SOFTCONN);
1272
1273        return PNFS_ATTEMPTED;
1274
1275out_failed:
1276        if (ff_layout_has_available_ds(lseg))
1277                return PNFS_TRY_AGAIN;
1278        return PNFS_NOT_ATTEMPTED;
1279}
1280
1281/* Perform async writes. */
1282static enum pnfs_try_status
1283ff_layout_write_pagelist(struct nfs_pgio_header *hdr, int sync)
1284{
1285        struct pnfs_layout_segment *lseg = hdr->lseg;
1286        struct nfs4_pnfs_ds *ds;
1287        struct rpc_clnt *ds_clnt;
1288        struct rpc_cred *ds_cred;
1289        loff_t offset = hdr->args.offset;
1290        int vers;
1291        struct nfs_fh *fh;
1292        int idx = hdr->pgio_mirror_idx;
1293
1294        ds = nfs4_ff_layout_prepare_ds(lseg, idx, true);
1295        if (!ds)
1296                return PNFS_NOT_ATTEMPTED;
1297
1298        ds_clnt = nfs4_ff_find_or_create_ds_client(lseg, idx, ds->ds_clp,
1299                                                   hdr->inode);
1300        if (IS_ERR(ds_clnt))
1301                return PNFS_NOT_ATTEMPTED;
1302
1303        ds_cred = ff_layout_get_ds_cred(lseg, idx, hdr->cred);
1304        if (IS_ERR(ds_cred))
1305                return PNFS_NOT_ATTEMPTED;
1306
1307        vers = nfs4_ff_layout_ds_version(lseg, idx);
1308
1309        dprintk("%s ino %lu sync %d req %Zu@%llu DS: %s cl_count %d vers %d\n",
1310                __func__, hdr->inode->i_ino, sync, (size_t) hdr->args.count,
1311                offset, ds->ds_remotestr, atomic_read(&ds->ds_clp->cl_count),
1312                vers);
1313
1314        hdr->pgio_done_cb = ff_layout_write_done_cb;
1315        atomic_inc(&ds->ds_clp->cl_count);
1316        hdr->ds_clp = ds->ds_clp;
1317        hdr->ds_commit_idx = idx;
1318        fh = nfs4_ff_layout_select_ds_fh(lseg, idx);
1319        if (fh)
1320                hdr->args.fh = fh;
1321
1322        /*
1323         * Note that if we ever decide to split across DSes,
1324         * then we may need to handle dense-like offsets.
1325         */
1326        hdr->args.offset = offset;
1327
1328        /* Perform an asynchronous write */
1329        nfs_initiate_pgio(ds_clnt, hdr, ds_cred, ds->ds_clp->rpc_ops,
1330                          vers == 3 ? &ff_layout_write_call_ops_v3 :
1331                                      &ff_layout_write_call_ops_v4,
1332                          sync, RPC_TASK_SOFTCONN);
1333        return PNFS_ATTEMPTED;
1334}
1335
1336static u32 calc_ds_index_from_commit(struct pnfs_layout_segment *lseg, u32 i)
1337{
1338        return i;
1339}
1340
1341static struct nfs_fh *
1342select_ds_fh_from_commit(struct pnfs_layout_segment *lseg, u32 i)
1343{
1344        struct nfs4_ff_layout_segment *flseg = FF_LAYOUT_LSEG(lseg);
1345
1346        /* FIXME: Assume that there is only one NFS version available
1347         * for the DS.
1348         */
1349        return &flseg->mirror_array[i]->fh_versions[0];
1350}
1351
1352static int ff_layout_initiate_commit(struct nfs_commit_data *data, int how)
1353{
1354        struct pnfs_layout_segment *lseg = data->lseg;
1355        struct nfs4_pnfs_ds *ds;
1356        struct rpc_clnt *ds_clnt;
1357        struct rpc_cred *ds_cred;
1358        u32 idx;
1359        int vers;
1360        struct nfs_fh *fh;
1361
1362        idx = calc_ds_index_from_commit(lseg, data->ds_commit_index);
1363        ds = nfs4_ff_layout_prepare_ds(lseg, idx, true);
1364        if (!ds)
1365                goto out_err;
1366
1367        ds_clnt = nfs4_ff_find_or_create_ds_client(lseg, idx, ds->ds_clp,
1368                                                   data->inode);
1369        if (IS_ERR(ds_clnt))
1370                goto out_err;
1371
1372        ds_cred = ff_layout_get_ds_cred(lseg, idx, data->cred);
1373        if (IS_ERR(ds_cred))
1374                goto out_err;
1375
1376        vers = nfs4_ff_layout_ds_version(lseg, idx);
1377
1378        dprintk("%s ino %lu, how %d cl_count %d vers %d\n", __func__,
1379                data->inode->i_ino, how, atomic_read(&ds->ds_clp->cl_count),
1380                vers);
1381        data->commit_done_cb = ff_layout_commit_done_cb;
1382        data->cred = ds_cred;
1383        atomic_inc(&ds->ds_clp->cl_count);
1384        data->ds_clp = ds->ds_clp;
1385        fh = select_ds_fh_from_commit(lseg, data->ds_commit_index);
1386        if (fh)
1387                data->args.fh = fh;
1388        return nfs_initiate_commit(ds_clnt, data, ds->ds_clp->rpc_ops,
1389                                   vers == 3 ? &ff_layout_commit_call_ops_v3 :
1390                                               &ff_layout_commit_call_ops_v4,
1391                                   how, RPC_TASK_SOFTCONN);
1392out_err:
1393        pnfs_generic_prepare_to_resend_writes(data);
1394        pnfs_generic_commit_release(data);
1395        return -EAGAIN;
1396}
1397
1398static int
1399ff_layout_commit_pagelist(struct inode *inode, struct list_head *mds_pages,
1400                           int how, struct nfs_commit_info *cinfo)
1401{
1402        return pnfs_generic_commit_pagelist(inode, mds_pages, how, cinfo,
1403                                            ff_layout_initiate_commit);
1404}
1405
1406static struct pnfs_ds_commit_info *
1407ff_layout_get_ds_info(struct inode *inode)
1408{
1409        struct pnfs_layout_hdr *layout = NFS_I(inode)->layout;
1410
1411        if (layout == NULL)
1412                return NULL;
1413
1414        return &FF_LAYOUT_FROM_HDR(layout)->commit_info;
1415}
1416
1417static void
1418ff_layout_free_deviceid_node(struct nfs4_deviceid_node *d)
1419{
1420        nfs4_ff_layout_free_deviceid(container_of(d, struct nfs4_ff_layout_ds,
1421                                                  id_node));
1422}
1423
1424static int ff_layout_encode_ioerr(struct nfs4_flexfile_layout *flo,
1425                                  struct xdr_stream *xdr,
1426                                  const struct nfs4_layoutreturn_args *args)
1427{
1428        struct pnfs_layout_hdr *hdr = &flo->generic_hdr;
1429        __be32 *start;
1430        int count = 0, ret = 0;
1431
1432        start = xdr_reserve_space(xdr, 4);
1433        if (unlikely(!start))
1434                return -E2BIG;
1435
1436        /* This assume we always return _ALL_ layouts */
1437        spin_lock(&hdr->plh_inode->i_lock);
1438        ret = ff_layout_encode_ds_ioerr(flo, xdr, &count, &args->range);
1439        spin_unlock(&hdr->plh_inode->i_lock);
1440
1441        *start = cpu_to_be32(count);
1442
1443        return ret;
1444}
1445
1446/* report nothing for now */
1447static void ff_layout_encode_iostats(struct nfs4_flexfile_layout *flo,
1448                                     struct xdr_stream *xdr,
1449                                     const struct nfs4_layoutreturn_args *args)
1450{
1451        __be32 *p;
1452
1453        p = xdr_reserve_space(xdr, 4);
1454        if (likely(p))
1455                *p = cpu_to_be32(0);
1456}
1457
1458static struct nfs4_deviceid_node *
1459ff_layout_alloc_deviceid_node(struct nfs_server *server,
1460                              struct pnfs_device *pdev, gfp_t gfp_flags)
1461{
1462        struct nfs4_ff_layout_ds *dsaddr;
1463
1464        dsaddr = nfs4_ff_alloc_deviceid_node(server, pdev, gfp_flags);
1465        if (!dsaddr)
1466                return NULL;
1467        return &dsaddr->id_node;
1468}
1469
1470static void
1471ff_layout_encode_layoutreturn(struct pnfs_layout_hdr *lo,
1472                              struct xdr_stream *xdr,
1473                              const struct nfs4_layoutreturn_args *args)
1474{
1475        struct nfs4_flexfile_layout *flo = FF_LAYOUT_FROM_HDR(lo);
1476        __be32 *start;
1477
1478        dprintk("%s: Begin\n", __func__);
1479        start = xdr_reserve_space(xdr, 4);
1480        BUG_ON(!start);
1481
1482        if (ff_layout_encode_ioerr(flo, xdr, args))
1483                goto out;
1484
1485        ff_layout_encode_iostats(flo, xdr, args);
1486out:
1487        *start = cpu_to_be32((xdr->p - start - 1) * 4);
1488        dprintk("%s: Return\n", __func__);
1489}
1490
1491static struct pnfs_layoutdriver_type flexfilelayout_type = {
1492        .id                     = LAYOUT_FLEX_FILES,
1493        .name                   = "LAYOUT_FLEX_FILES",
1494        .owner                  = THIS_MODULE,
1495        .alloc_layout_hdr       = ff_layout_alloc_layout_hdr,
1496        .free_layout_hdr        = ff_layout_free_layout_hdr,
1497        .alloc_lseg             = ff_layout_alloc_lseg,
1498        .free_lseg              = ff_layout_free_lseg,
1499        .pg_read_ops            = &ff_layout_pg_read_ops,
1500        .pg_write_ops           = &ff_layout_pg_write_ops,
1501        .get_ds_info            = ff_layout_get_ds_info,
1502        .free_deviceid_node     = ff_layout_free_deviceid_node,
1503        .mark_request_commit    = pnfs_layout_mark_request_commit,
1504        .clear_request_commit   = pnfs_generic_clear_request_commit,
1505        .scan_commit_lists      = pnfs_generic_scan_commit_lists,
1506        .recover_commit_reqs    = pnfs_generic_recover_commit_reqs,
1507        .commit_pagelist        = ff_layout_commit_pagelist,
1508        .read_pagelist          = ff_layout_read_pagelist,
1509        .write_pagelist         = ff_layout_write_pagelist,
1510        .alloc_deviceid_node    = ff_layout_alloc_deviceid_node,
1511        .encode_layoutreturn    = ff_layout_encode_layoutreturn,
1512        .sync                   = pnfs_nfs_generic_sync,
1513};
1514
1515static int __init nfs4flexfilelayout_init(void)
1516{
1517        printk(KERN_INFO "%s: NFSv4 Flexfile Layout Driver Registering...\n",
1518               __func__);
1519        return pnfs_register_layoutdriver(&flexfilelayout_type);
1520}
1521
1522static void __exit nfs4flexfilelayout_exit(void)
1523{
1524        printk(KERN_INFO "%s: NFSv4 Flexfile Layout Driver Unregistering...\n",
1525               __func__);
1526        pnfs_unregister_layoutdriver(&flexfilelayout_type);
1527}
1528
1529MODULE_ALIAS("nfs-layouttype4-4");
1530
1531MODULE_LICENSE("GPL");
1532MODULE_DESCRIPTION("The NFSv4 flexfile layout driver");
1533
1534module_init(nfs4flexfilelayout_init);
1535module_exit(nfs4flexfilelayout_exit);
1536