fs/nfs/blocklayout/blocklayout.c

   1 /*
   2  *  linux/fs/nfs/blocklayout/blocklayout.c
   3  *
   4  *  Module for the NFSv4.1 pNFS block layout driver.
   5  *
   6  *  Copyright (c) 2006 The Regents of the University of Michigan.
   7  *  All rights reserved.
   8  *
   9  *  Andy Adamson <andros@citi.umich.edu>
  10  *  Fred Isaman <iisaman@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 from the
  22  * university of michigan as to its fitness for any purpose, and without
  23  * warranty by the university of michigan of any kind, either express
  24  * or implied, including without limitation the implied warranties of
  25  * merchantability and fitness for a particular purpose.  the regents
  26  * of the university of michigan shall not be liable for any damages,
  27  * including special, indirect, incidental, or consequential damages,
  28  * with respect to any claim arising out or in connection with the use
  29  * of the software, even if it has been or is hereafter advised of the
  30  * possibility of such damages.
  31  */
  32
  33 #include <linux/module.h>
  34 #include <linux/init.h>
  35 #include <linux/mount.h>
  36 #include <linux/namei.h>
  37 #include <linux/bio.h>          /* struct bio */
  38 #include <linux/buffer_head.h>  /* various write calls */
  39 #include <linux/prefetch.h>
  40
  41 #include "../pnfs.h"
  42 #include "../internal.h"
  43 #include "blocklayout.h"
  44
  45 #define NFSDBG_FACILITY NFSDBG_PNFS_LD
  46
  47 MODULE_LICENSE("GPL");
  48 MODULE_AUTHOR("Andy Adamson <andros@citi.umich.edu>");
  49 MODULE_DESCRIPTION("The NFSv4.1 pNFS Block layout driver");
  50
  51 static void print_page(struct page *page)
  52 {
  53         dprintk("PRINTPAGE page %p\n", page);
  54         dprintk("       PagePrivate %d\n", PagePrivate(page));
  55         dprintk("       PageUptodate %d\n", PageUptodate(page));
  56         dprintk("       PageError %d\n", PageError(page));
  57         dprintk("       PageDirty %d\n", PageDirty(page));
  58         dprintk("       PageReferenced %d\n", PageReferenced(page));
  59         dprintk("       PageLocked %d\n", PageLocked(page));
  60         dprintk("       PageWriteback %d\n", PageWriteback(page));
  61         dprintk("       PageMappedToDisk %d\n", PageMappedToDisk(page));
  62         dprintk("\n");
  63 }
  64
  65 /* Given the be associated with isect, determine if page data needs to be
  66  * initialized.
  67  */
  68 static int is_hole(struct pnfs_block_extent *be, sector_t isect)
  69 {
  70         if (be->be_state == PNFS_BLOCK_NONE_DATA)
  71                 return 1;
  72         else if (be->be_state != PNFS_BLOCK_INVALID_DATA)
  73                 return 0;
  74         else
  75                 return !bl_is_sector_init(be->be_inval, isect);
  76 }
  77
  78 /* Given the be associated with isect, determine if page data can be
  79  * written to disk.
  80  */
  81 static int is_writable(struct pnfs_block_extent *be, sector_t isect)
  82 {
  83         return (be->be_state == PNFS_BLOCK_READWRITE_DATA ||
  84                 be->be_state == PNFS_BLOCK_INVALID_DATA);
  85 }
  86
  87 /* The data we are handed might be spread across several bios.  We need
  88  * to track when the last one is finished.
  89  */
  90 struct parallel_io {
  91         struct kref refcnt;
  92         void (*pnfs_callback) (void *data, int num_se);
  93         void *data;
  94         int bse_count;
  95 };
  96
  97 static inline struct parallel_io *alloc_parallel(void *data)
  98 {
  99         struct parallel_io *rv;
 100
 101         rv  = kmalloc(sizeof(*rv), GFP_NOFS);
 102         if (rv) {
 103                 rv->data = data;
 104                 kref_init(&rv->refcnt);
 105                 rv->bse_count = 0;
 106         }
 107         return rv;
 108 }
 109
 110 static inline void get_parallel(struct parallel_io *p)
 111 {
 112         kref_get(&p->refcnt);
 113 }
 114
 115 static void destroy_parallel(struct kref *kref)
 116 {
 117         struct parallel_io *p = container_of(kref, struct parallel_io, refcnt);
 118
 119         dprintk("%s enter\n", __func__);
 120         p->pnfs_callback(p->data, p->bse_count);
 121         kfree(p);
 122 }
 123
 124 static inline void put_parallel(struct parallel_io *p)
 125 {
 126         kref_put(&p->refcnt, destroy_parallel);
 127 }
 128
 129 static struct bio *
 130 bl_submit_bio(int rw, struct bio *bio)
 131 {
 132         if (bio) {
 133                 get_parallel(bio->bi_private);
 134                 dprintk("%s submitting %s bio %u@%llu\n", __func__,
 135                         rw == READ ? "read" : "write",
 136                         bio->bi_size, (unsigned long long)bio->bi_sector);
 137                 submit_bio(rw, bio);
 138         }
 139         return NULL;
 140 }
 141
 142 static struct bio *bl_alloc_init_bio(int npg, sector_t isect,
 143                                      struct pnfs_block_extent *be,
 144                                      void (*end_io)(struct bio *, int err),
 145                                      struct parallel_io *par)
 146 {
 147         struct bio *bio;
 148
 149         npg = min(npg, BIO_MAX_PAGES);
 150         bio = bio_alloc(GFP_NOIO, npg);
 151         if (!bio && (current->flags & PF_MEMALLOC)) {
 152                 while (!bio && (npg /= 2))
 153                         bio = bio_alloc(GFP_NOIO, npg);
 154         }
 155
 156         if (bio) {
 157                 bio->bi_sector = isect - be->be_f_offset + be->be_v_offset;
 158                 bio->bi_bdev = be->be_mdev;
 159                 bio->bi_end_io = end_io;
 160                 bio->bi_private = par;
 161         }
 162         return bio;
 163 }
 164
 165 static struct bio *bl_add_page_to_bio(struct bio *bio, int npg, int rw,
 166                                       sector_t isect, struct page *page,
 167                                       struct pnfs_block_extent *be,
 168                                       void (*end_io)(struct bio *, int err),
 169                                       struct parallel_io *par)
 170 {
 171 retry:
 172         if (!bio) {
 173                 bio = bl_alloc_init_bio(npg, isect, be, end_io, par);
 174                 if (!bio)
 175                         return ERR_PTR(-ENOMEM);
 176         }
 177         if (bio_add_page(bio, page, PAGE_CACHE_SIZE, 0) < PAGE_CACHE_SIZE) {
 178                 bio = bl_submit_bio(rw, bio);
 179                 goto retry;
 180         }
 181         return bio;
 182 }
 183
 184 /* This is basically copied from mpage_end_io_read */
 185 static void bl_end_io_read(struct bio *bio, int err)
 186 {
 187         struct parallel_io *par = bio->bi_private;
 188         const int uptodate = test_bit(BIO_UPTODATE, &bio->bi_flags);
 189         struct bio_vec *bvec = bio->bi_io_vec + bio->bi_vcnt - 1;
 190
 191         do {
 192                 struct page *page = bvec->bv_page;
 193
 194                 if (--bvec >= bio->bi_io_vec)
 195                         prefetchw(&bvec->bv_page->flags);
 196                 if (uptodate)
 197                         SetPageUptodate(page);
 198         } while (bvec >= bio->bi_io_vec);
 199         if (!uptodate) {
 200                 struct nfs_read_data *rdata = par->data;
 201                 struct nfs_pgio_header *header = rdata->header;
 202
 203                 if (!header->pnfs_error)
 204                         header->pnfs_error = -EIO;
 205                 pnfs_set_lo_fail(header->lseg);
 206         }
 207         bio_put(bio);
 208         put_parallel(par);
 209 }
 210
 211 static void bl_read_cleanup(struct work_struct *work)
 212 {
 213         struct rpc_task *task;
 214         struct nfs_read_data *rdata;
 215         dprintk("%s enter\n", __func__);
 216         task = container_of(work, struct rpc_task, u.tk_work);
 217         rdata = container_of(task, struct nfs_read_data, task);
 218         pnfs_ld_read_done(rdata);
 219 }
 220
 221 static void
 222 bl_end_par_io_read(void *data, int unused)
 223 {
 224         struct nfs_read_data *rdata = data;
 225
 226         rdata->task.tk_status = rdata->header->pnfs_error;
 227         INIT_WORK(&rdata->task.u.tk_work, bl_read_cleanup);
 228         schedule_work(&rdata->task.u.tk_work);
 229 }
 230
 231 static enum pnfs_try_status
 232 bl_read_pagelist(struct nfs_read_data *rdata)
 233 {
 234         struct nfs_pgio_header *header = rdata->header;
 235         int i, hole;
 236         struct bio *bio = NULL;
 237         struct pnfs_block_extent *be = NULL, *cow_read = NULL;
 238         sector_t isect, extent_length = 0;
 239         struct parallel_io *par;
 240         loff_t f_offset = rdata->args.offset;
 241         struct page **pages = rdata->args.pages;
 242         int pg_index = rdata->args.pgbase >> PAGE_CACHE_SHIFT;
 243
 244         dprintk("%s enter nr_pages %u offset %lld count %u\n", __func__,
 245                rdata->pages.npages, f_offset, (unsigned int)rdata->args.count);
 246
 247         par = alloc_parallel(rdata);
 248         if (!par)
 249                 goto use_mds;
 250         par->pnfs_callback = bl_end_par_io_read;
 251         /* At this point, we can no longer jump to use_mds */
 252
 253         isect = (sector_t) (f_offset >> SECTOR_SHIFT);
 254         /* Code assumes extents are page-aligned */
 255         for (i = pg_index; i < rdata->pages.npages; i++) {
 256                 if (!extent_length) {
 257                         /* We've used up the previous extent */
 258                         bl_put_extent(be);
 259                         bl_put_extent(cow_read);
 260                         bio = bl_submit_bio(READ, bio);
 261                         /* Get the next one */
 262                         be = bl_find_get_extent(BLK_LSEG2EXT(header->lseg),
 263                                              isect, &cow_read);
 264                         if (!be) {
 265                                 header->pnfs_error = -EIO;
 266                                 goto out;
 267                         }
 268                         extent_length = be->be_length -
 269                                 (isect - be->be_f_offset);
 270                         if (cow_read) {
 271                                 sector_t cow_length = cow_read->be_length -
 272                                         (isect - cow_read->be_f_offset);
 273                                 extent_length = min(extent_length, cow_length);
 274                         }
 275                 }
 276                 hole = is_hole(be, isect);
 277                 if (hole && !cow_read) {
 278                         bio = bl_submit_bio(READ, bio);
 279                         /* Fill hole w/ zeroes w/o accessing device */
 280                         dprintk("%s Zeroing page for hole\n", __func__);
 281                         zero_user_segment(pages[i], 0, PAGE_CACHE_SIZE);
 282                         print_page(pages[i]);
 283                         SetPageUptodate(pages[i]);
 284                 } else {
 285                         struct pnfs_block_extent *be_read;
 286
 287                         be_read = (hole && cow_read) ? cow_read : be;
 288                         bio = bl_add_page_to_bio(bio, rdata->pages.npages - i,
 289                                                  READ,
 290                                                  isect, pages[i], be_read,
 291                                                  bl_end_io_read, par);
 292                         if (IS_ERR(bio)) {
 293                                 header->pnfs_error = PTR_ERR(bio);
 294                                 bio = NULL;
 295                                 goto out;
 296                         }
 297                 }
 298                 isect += PAGE_CACHE_SECTORS;
 299                 extent_length -= PAGE_CACHE_SECTORS;
 300         }
 301         if ((isect << SECTOR_SHIFT) >= header->inode->i_size) {
 302                 rdata->res.eof = 1;
 303                 rdata->res.count = header->inode->i_size - f_offset;
 304         } else {
 305                 rdata->res.count = (isect << SECTOR_SHIFT) - f_offset;
 306         }
 307 out:
 308         bl_put_extent(be);
 309         bl_put_extent(cow_read);
 310         bl_submit_bio(READ, bio);
 311         put_parallel(par);
 312         return PNFS_ATTEMPTED;
 313
 314  use_mds:
 315         dprintk("Giving up and using normal NFS\n");
 316         return PNFS_NOT_ATTEMPTED;
 317 }
 318
 319 static void mark_extents_written(struct pnfs_block_layout *bl,
 320                                  __u64 offset, __u32 count)
 321 {
 322         sector_t isect, end;
 323         struct pnfs_block_extent *be;
 324         struct pnfs_block_short_extent *se;
 325
 326         dprintk("%s(%llu, %u)\n", __func__, offset, count);
 327         if (count == 0)
 328                 return;
 329         isect = (offset & (long)(PAGE_CACHE_MASK)) >> SECTOR_SHIFT;
 330         end = (offset + count + PAGE_CACHE_SIZE - 1) & (long)(PAGE_CACHE_MASK);
 331         end >>= SECTOR_SHIFT;
 332         while (isect < end) {
 333                 sector_t len;
 334                 be = bl_find_get_extent(bl, isect, NULL);
 335                 BUG_ON(!be); /* FIXME */
 336                 len = min(end, be->be_f_offset + be->be_length) - isect;
 337                 if (be->be_state == PNFS_BLOCK_INVALID_DATA) {
 338                         se = bl_pop_one_short_extent(be->be_inval);
 339                         BUG_ON(!se);
 340                         bl_mark_for_commit(be, isect, len, se);
 341                 }
 342                 isect += len;
 343                 bl_put_extent(be);
 344         }
 345 }
 346
 347 static void bl_end_io_write_zero(struct bio *bio, int err)
 348 {
 349         struct parallel_io *par = bio->bi_private;
 350         const int uptodate = test_bit(BIO_UPTODATE, &bio->bi_flags);
 351         struct bio_vec *bvec = bio->bi_io_vec + bio->bi_vcnt - 1;
 352
 353         do {
 354                 struct page *page = bvec->bv_page;
 355
 356                 if (--bvec >= bio->bi_io_vec)
 357                         prefetchw(&bvec->bv_page->flags);
 358                 /* This is the zeroing page we added */
 359                 end_page_writeback(page);
 360                 page_cache_release(page);
 361         } while (bvec >= bio->bi_io_vec);
 362
 363         if (unlikely(!uptodate)) {
 364                 struct nfs_write_data *data = par->data;
 365                 struct nfs_pgio_header *header = data->header;
 366
 367                 if (!header->pnfs_error)
 368                         header->pnfs_error = -EIO;
 369                 pnfs_set_lo_fail(header->lseg);
 370         }
 371         bio_put(bio);
 372         put_parallel(par);
 373 }
 374
 375 static void bl_end_io_write(struct bio *bio, int err)
 376 {
 377         struct parallel_io *par = bio->bi_private;
 378         const int uptodate = test_bit(BIO_UPTODATE, &bio->bi_flags);
 379         struct nfs_write_data *data = par->data;
 380         struct nfs_pgio_header *header = data->header;
 381
 382         if (!uptodate) {
 383                 if (!header->pnfs_error)
 384                         header->pnfs_error = -EIO;
 385                 pnfs_set_lo_fail(header->lseg);
 386         }
 387         bio_put(bio);
 388         put_parallel(par);
 389 }
 390
 391 /* Function scheduled for call during bl_end_par_io_write,
 392  * it marks sectors as written and extends the commitlist.
 393  */
 394 static void bl_write_cleanup(struct work_struct *work)
 395 {
 396         struct rpc_task *task;
 397         struct nfs_write_data *wdata;
 398         dprintk("%s enter\n", __func__);
 399         task = container_of(work, struct rpc_task, u.tk_work);
 400         wdata = container_of(task, struct nfs_write_data, task);
 401         if (likely(!wdata->header->pnfs_error)) {
 402                 /* Marks for LAYOUTCOMMIT */
 403                 mark_extents_written(BLK_LSEG2EXT(wdata->header->lseg),
 404                                      wdata->args.offset, wdata->args.count);
 405         }
 406         pnfs_ld_write_done(wdata);
 407 }
 408
 409 /* Called when last of bios associated with a bl_write_pagelist call finishes */
 410 static void bl_end_par_io_write(void *data, int num_se)
 411 {
 412         struct nfs_write_data *wdata = data;
 413
 414         if (unlikely(wdata->header->pnfs_error)) {
 415                 bl_free_short_extents(&BLK_LSEG2EXT(wdata->header->lseg)->bl_inval,
 416                                         num_se);
 417         }
 418
 419         wdata->task.tk_status = wdata->header->pnfs_error;
 420         wdata->verf.committed = NFS_FILE_SYNC;
 421         INIT_WORK(&wdata->task.u.tk_work, bl_write_cleanup);
 422         schedule_work(&wdata->task.u.tk_work);
 423 }
 424
 425 /* FIXME STUB - mark intersection of layout and page as bad, so is not
 426  * used again.
 427  */
 428 static void mark_bad_read(void)
 429 {
 430         return;
 431 }
 432
 433 /*
 434  * map_block:  map a requested I/0 block (isect) into an offset in the LVM
 435  * block_device
 436  */
 437 static void
 438 map_block(struct buffer_head *bh, sector_t isect, struct pnfs_block_extent *be)
 439 {
 440         dprintk("%s enter be=%p\n", __func__, be);
 441
 442         set_buffer_mapped(bh);
 443         bh->b_bdev = be->be_mdev;
 444         bh->b_blocknr = (isect - be->be_f_offset + be->be_v_offset) >>
 445             (be->be_mdev->bd_inode->i_blkbits - SECTOR_SHIFT);
 446
 447         dprintk("%s isect %llu, bh->b_blocknr %ld, using bsize %Zd\n",
 448                 __func__, (unsigned long long)isect, (long)bh->b_blocknr,
 449                 bh->b_size);
 450         return;
 451 }
 452
 453 /* Given an unmapped page, zero it or read in page for COW, page is locked
 454  * by caller.
 455  */
 456 static int
 457 init_page_for_write(struct page *page, struct pnfs_block_extent *cow_read)
 458 {
 459         struct buffer_head *bh = NULL;
 460         int ret = 0;
 461         sector_t isect;
 462
 463         dprintk("%s enter, %p\n", __func__, page);
 464         BUG_ON(PageUptodate(page));
 465         if (!cow_read) {
 466                 zero_user_segment(page, 0, PAGE_SIZE);
 467                 SetPageUptodate(page);
 468                 goto cleanup;
 469         }
 470
 471         bh = alloc_page_buffers(page, PAGE_CACHE_SIZE, 0);
 472         if (!bh) {
 473                 ret = -ENOMEM;
 474                 goto cleanup;
 475         }
 476
 477         isect = (sector_t) page->index << PAGE_CACHE_SECTOR_SHIFT;
 478         map_block(bh, isect, cow_read);
 479         if (!bh_uptodate_or_lock(bh))
 480                 ret = bh_submit_read(bh);
 481         if (ret)
 482                 goto cleanup;
 483         SetPageUptodate(page);
 484
 485 cleanup:
 486         bl_put_extent(cow_read);
 487         if (bh)
 488                 free_buffer_head(bh);
 489         if (ret) {
 490                 /* Need to mark layout with bad read...should now
 491                  * just use nfs4 for reads and writes.
 492                  */
 493                 mark_bad_read();
 494         }
 495         return ret;
 496 }
 497
 498 /* Find or create a zeroing page marked being writeback.
 499  * Return ERR_PTR on error, NULL to indicate skip this page and page itself
 500  * to indicate write out.
 501  */
 502 static struct page *
 503 bl_find_get_zeroing_page(struct inode *inode, pgoff_t index,
 504                         struct pnfs_block_extent *cow_read)
 505 {
 506         struct page *page;
 507         int locked = 0;
 508         page = find_get_page(inode->i_mapping, index);
 509         if (page)
 510                 goto check_page;
 511
 512         page = find_or_create_page(inode->i_mapping, index, GFP_NOFS);
 513         if (unlikely(!page)) {
 514                 dprintk("%s oom\n", __func__);
 515                 return ERR_PTR(-ENOMEM);
 516         }
 517         locked = 1;
 518
 519 check_page:
 520         /* PageDirty: Other will write this out
 521          * PageWriteback: Other is writing this out
 522          * PageUptodate: It was read before
 523          */
 524         if (PageDirty(page) || PageWriteback(page)) {
 525                 print_page(page);
 526                 if (locked)
 527                         unlock_page(page);
 528                 page_cache_release(page);
 529                 return NULL;
 530         }
 531
 532         if (!locked) {
 533                 lock_page(page);
 534                 locked = 1;
 535                 goto check_page;
 536         }
 537         if (!PageUptodate(page)) {
 538                 /* New page, readin or zero it */
 539                 init_page_for_write(page, cow_read);
 540         }
 541         set_page_writeback(page);
 542         unlock_page(page);
 543
 544         return page;
 545 }
 546
 547 static enum pnfs_try_status
 548 bl_write_pagelist(struct nfs_write_data *wdata, int sync)
 549 {
 550         struct nfs_pgio_header *header = wdata->header;
 551         int i, ret, npg_zero, pg_index, last = 0;
 552         struct bio *bio = NULL;
 553         struct pnfs_block_extent *be = NULL, *cow_read = NULL;
 554         sector_t isect, last_isect = 0, extent_length = 0;
 555         struct parallel_io *par;
 556         loff_t offset = wdata->args.offset;
 557         size_t count = wdata->args.count;
 558         struct page **pages = wdata->args.pages;
 559         struct page *page;
 560         pgoff_t index;
 561         u64 temp;
 562         int npg_per_block =
 563             NFS_SERVER(header->inode)->pnfs_blksize >> PAGE_CACHE_SHIFT;
 564
 565         dprintk("%s enter, %Zu@%lld\n", __func__, count, offset);
 566         /* At this point, wdata->pages is a (sequential) list of nfs_pages.
 567          * We want to write each, and if there is an error set pnfs_error
 568          * to have it redone using nfs.
 569          */
 570         par = alloc_parallel(wdata);
 571         if (!par)
 572                 goto out_mds;
 573         par->pnfs_callback = bl_end_par_io_write;
 574         /* At this point, have to be more careful with error handling */
 575
 576         isect = (sector_t) ((offset & (long)PAGE_CACHE_MASK) >> SECTOR_SHIFT);
 577         be = bl_find_get_extent(BLK_LSEG2EXT(header->lseg), isect, &cow_read);
 578         if (!be || !is_writable(be, isect)) {
 579                 dprintk("%s no matching extents!\n", __func__);
 580                 goto out_mds;
 581         }
 582
 583         /* First page inside INVALID extent */
 584         if (be->be_state == PNFS_BLOCK_INVALID_DATA) {
 585                 if (likely(!bl_push_one_short_extent(be->be_inval)))
 586                         par->bse_count++;
 587                 else
 588                         goto out_mds;
 589                 temp = offset >> PAGE_CACHE_SHIFT;
 590                 npg_zero = do_div(temp, npg_per_block);
 591                 isect = (sector_t) (((offset - npg_zero * PAGE_CACHE_SIZE) &
 592                                      (long)PAGE_CACHE_MASK) >> SECTOR_SHIFT);
 593                 extent_length = be->be_length - (isect - be->be_f_offset);
 594
 595 fill_invalid_ext:
 596                 dprintk("%s need to zero %d pages\n", __func__, npg_zero);
 597                 for (;npg_zero > 0; npg_zero--) {
 598                         if (bl_is_sector_init(be->be_inval, isect)) {
 599                                 dprintk("isect %llu already init\n",
 600                                         (unsigned long long)isect);
 601                                 goto next_page;
 602                         }
 603                         /* page ref released in bl_end_io_write_zero */
 604                         index = isect >> PAGE_CACHE_SECTOR_SHIFT;
 605                         dprintk("%s zero %dth page: index %lu isect %llu\n",
 606                                 __func__, npg_zero, index,
 607                                 (unsigned long long)isect);
 608                         page = bl_find_get_zeroing_page(header->inode, index,
 609                                                         cow_read);
 610                         if (unlikely(IS_ERR(page))) {
 611                                 header->pnfs_error = PTR_ERR(page);
 612                                 goto out;
 613                         } else if (page == NULL)
 614                                 goto next_page;
 615
 616                         ret = bl_mark_sectors_init(be->be_inval, isect,
 617                                                        PAGE_CACHE_SECTORS);
 618                         if (unlikely(ret)) {
 619                                 dprintk("%s bl_mark_sectors_init fail %d\n",
 620                                         __func__, ret);
 621                                 end_page_writeback(page);
 622                                 page_cache_release(page);
 623                                 header->pnfs_error = ret;
 624                                 goto out;
 625                         }
 626                         if (likely(!bl_push_one_short_extent(be->be_inval)))
 627                                 par->bse_count++;
 628                         else {
 629                                 end_page_writeback(page);
 630                                 page_cache_release(page);
 631                                 header->pnfs_error = -ENOMEM;
 632                                 goto out;
 633                         }
 634                         /* FIXME: This should be done in bi_end_io */
 635                         mark_extents_written(BLK_LSEG2EXT(header->lseg),
 636                                              page->index << PAGE_CACHE_SHIFT,
 637                                              PAGE_CACHE_SIZE);
 638
 639                         bio = bl_add_page_to_bio(bio, npg_zero, WRITE,
 640                                                  isect, page, be,
 641                                                  bl_end_io_write_zero, par);
 642                         if (IS_ERR(bio)) {
 643                                 header->pnfs_error = PTR_ERR(bio);
 644                                 bio = NULL;
 645                                 goto out;
 646                         }
 647 next_page:
 648                         isect += PAGE_CACHE_SECTORS;
 649                         extent_length -= PAGE_CACHE_SECTORS;
 650                 }
 651                 if (last)
 652                         goto write_done;
 653         }
 654         bio = bl_submit_bio(WRITE, bio);
 655
 656         /* Middle pages */
 657         pg_index = wdata->args.pgbase >> PAGE_CACHE_SHIFT;
 658         for (i = pg_index; i < wdata->pages.npages; i++) {
 659                 if (!extent_length) {
 660                         /* We've used up the previous extent */
 661                         bl_put_extent(be);
 662                         bio = bl_submit_bio(WRITE, bio);
 663                         /* Get the next one */
 664                         be = bl_find_get_extent(BLK_LSEG2EXT(header->lseg),
 665                                              isect, NULL);
 666                         if (!be || !is_writable(be, isect)) {
 667                                 header->pnfs_error = -EINVAL;
 668                                 goto out;
 669                         }
 670                         if (be->be_state == PNFS_BLOCK_INVALID_DATA) {
 671                                 if (likely(!bl_push_one_short_extent(
 672                                                                 be->be_inval)))
 673                                         par->bse_count++;
 674                                 else {
 675                                         header->pnfs_error = -ENOMEM;
 676                                         goto out;
 677                                 }
 678                         }
 679                         extent_length = be->be_length -
 680                             (isect - be->be_f_offset);
 681                 }
 682                 if (be->be_state == PNFS_BLOCK_INVALID_DATA) {
 683                         ret = bl_mark_sectors_init(be->be_inval, isect,
 684                                                        PAGE_CACHE_SECTORS);
 685                         if (unlikely(ret)) {
 686                                 dprintk("%s bl_mark_sectors_init fail %d\n",
 687                                         __func__, ret);
 688                                 header->pnfs_error = ret;
 689                                 goto out;
 690                         }
 691                 }
 692                 bio = bl_add_page_to_bio(bio, wdata->pages.npages - i, WRITE,
 693                                          isect, pages[i], be,
 694                                          bl_end_io_write, par);
 695                 if (IS_ERR(bio)) {
 696                         header->pnfs_error = PTR_ERR(bio);
 697                         bio = NULL;
 698                         goto out;
 699                 }
 700                 isect += PAGE_CACHE_SECTORS;
 701                 last_isect = isect;
 702                 extent_length -= PAGE_CACHE_SECTORS;
 703         }
 704
 705         /* Last page inside INVALID extent */
 706         if (be->be_state == PNFS_BLOCK_INVALID_DATA) {
 707                 bio = bl_submit_bio(WRITE, bio);
 708                 temp = last_isect >> PAGE_CACHE_SECTOR_SHIFT;
 709                 npg_zero = npg_per_block - do_div(temp, npg_per_block);
 710                 if (npg_zero < npg_per_block) {
 711                         last = 1;
 712                         goto fill_invalid_ext;
 713                 }
 714         }
 715
 716 write_done:
 717         wdata->res.count = (last_isect << SECTOR_SHIFT) - (offset);
 718         if (count < wdata->res.count) {
 719                 wdata->res.count = count;
 720         }
 721 out:
 722         bl_put_extent(be);
 723         bl_submit_bio(WRITE, bio);
 724         put_parallel(par);
 725         return PNFS_ATTEMPTED;
 726 out_mds:
 727         bl_put_extent(be);
 728         kfree(par);
 729         return PNFS_NOT_ATTEMPTED;
 730 }
 731
 732 /* FIXME - range ignored */
 733 static void
 734 release_extents(struct pnfs_block_layout *bl, struct pnfs_layout_range *range)
 735 {
 736         int i;
 737         struct pnfs_block_extent *be;
 738
 739         spin_lock(&bl->bl_ext_lock);
 740         for (i = 0; i < EXTENT_LISTS; i++) {
 741                 while (!list_empty(&bl->bl_extents[i])) {
 742                         be = list_first_entry(&bl->bl_extents[i],
 743                                               struct pnfs_block_extent,
 744                                               be_node);
 745                         list_del(&be->be_node);
 746                         bl_put_extent(be);
 747                 }
 748         }
 749         spin_unlock(&bl->bl_ext_lock);
 750 }
 751
 752 static void
 753 release_inval_marks(struct pnfs_inval_markings *marks)
 754 {
 755         struct pnfs_inval_tracking *pos, *temp;
 756         struct pnfs_block_short_extent *se, *stemp;
 757
 758         list_for_each_entry_safe(pos, temp, &marks->im_tree.mtt_stub, it_link) {
 759                 list_del(&pos->it_link);
 760                 kfree(pos);
 761         }
 762
 763         list_for_each_entry_safe(se, stemp, &marks->im_extents, bse_node) {
 764                 list_del(&se->bse_node);
 765                 kfree(se);
 766         }
 767         return;
 768 }
 769
 770 static void bl_free_layout_hdr(struct pnfs_layout_hdr *lo)
 771 {
 772         struct pnfs_block_layout *bl = BLK_LO2EXT(lo);
 773
 774         dprintk("%s enter\n", __func__);
 775         release_extents(bl, NULL);
 776         release_inval_marks(&bl->bl_inval);
 777         kfree(bl);
 778 }
 779
 780 static struct pnfs_layout_hdr *bl_alloc_layout_hdr(struct inode *inode,
 781                                                    gfp_t gfp_flags)
 782 {
 783         struct pnfs_block_layout *bl;
 784
 785         dprintk("%s enter\n", __func__);
 786         bl = kzalloc(sizeof(*bl), gfp_flags);
 787         if (!bl)
 788                 return NULL;
 789         spin_lock_init(&bl->bl_ext_lock);
 790         INIT_LIST_HEAD(&bl->bl_extents[0]);
 791         INIT_LIST_HEAD(&bl->bl_extents[1]);
 792         INIT_LIST_HEAD(&bl->bl_commit);
 793         INIT_LIST_HEAD(&bl->bl_committing);
 794         bl->bl_count = 0;
 795         bl->bl_blocksize = NFS_SERVER(inode)->pnfs_blksize >> SECTOR_SHIFT;
 796         BL_INIT_INVAL_MARKS(&bl->bl_inval, bl->bl_blocksize);
 797         return &bl->bl_layout;
 798 }
 799
 800 static void bl_free_lseg(struct pnfs_layout_segment *lseg)
 801 {
 802         dprintk("%s enter\n", __func__);
 803         kfree(lseg);
 804 }
 805
 806 /* We pretty much ignore lseg, and store all data layout wide, so we
 807  * can correctly merge.
 808  */
 809 static struct pnfs_layout_segment *bl_alloc_lseg(struct pnfs_layout_hdr *lo,
 810                                                  struct nfs4_layoutget_res *lgr,
 811                                                  gfp_t gfp_flags)
 812 {
 813         struct pnfs_layout_segment *lseg;
 814         int status;
 815
 816         dprintk("%s enter\n", __func__);
 817         lseg = kzalloc(sizeof(*lseg), gfp_flags);
 818         if (!lseg)
 819                 return ERR_PTR(-ENOMEM);
 820         status = nfs4_blk_process_layoutget(lo, lgr, gfp_flags);
 821         if (status) {
 822                 /* We don't want to call the full-blown bl_free_lseg,
 823                  * since on error extents were not touched.
 824                  */
 825                 kfree(lseg);
 826                 return ERR_PTR(status);
 827         }
 828         return lseg;
 829 }
 830
 831 static void
 832 bl_encode_layoutcommit(struct pnfs_layout_hdr *lo, struct xdr_stream *xdr,
 833                        const struct nfs4_layoutcommit_args *arg)
 834 {
 835         dprintk("%s enter\n", __func__);
 836         encode_pnfs_block_layoutupdate(BLK_LO2EXT(lo), xdr, arg);
 837 }
 838
 839 static void
 840 bl_cleanup_layoutcommit(struct nfs4_layoutcommit_data *lcdata)
 841 {
 842         struct pnfs_layout_hdr *lo = NFS_I(lcdata->args.inode)->layout;
 843
 844         dprintk("%s enter\n", __func__);
 845         clean_pnfs_block_layoutupdate(BLK_LO2EXT(lo), &lcdata->args, lcdata->res.status);
 846 }
 847
 848 static void free_blk_mountid(struct block_mount_id *mid)
 849 {
 850         if (mid) {
 851                 struct pnfs_block_dev *dev, *tmp;
 852
 853                 /* No need to take bm_lock as we are last user freeing bm_devlist */
 854                 list_for_each_entry_safe(dev, tmp, &mid->bm_devlist, bm_node) {
 855                         list_del(&dev->bm_node);
 856                         bl_free_block_dev(dev);
 857                 }
 858                 kfree(mid);
 859         }
 860 }
 861
 862 /* This is mostly copied from the filelayout's get_device_info function.
 863  * It seems much of this should be at the generic pnfs level.
 864  */
 865 static struct pnfs_block_dev *
 866 nfs4_blk_get_deviceinfo(struct nfs_server *server, const struct nfs_fh *fh,
 867                         struct nfs4_deviceid *d_id)
 868 {
 869         struct pnfs_device *dev;
 870         struct pnfs_block_dev *rv;
 871         u32 max_resp_sz;
 872         int max_pages;
 873         struct page **pages = NULL;
 874         int i, rc;
 875
 876         /*
 877          * Use the session max response size as the basis for setting
 878          * GETDEVICEINFO's maxcount
 879          */
 880         max_resp_sz = server->nfs_client->cl_session->fc_attrs.max_resp_sz;
 881         max_pages = nfs_page_array_len(0, max_resp_sz);
 882         dprintk("%s max_resp_sz %u max_pages %d\n",
 883                 __func__, max_resp_sz, max_pages);
 884
 885         dev = kmalloc(sizeof(*dev), GFP_NOFS);
 886         if (!dev) {
 887                 dprintk("%s kmalloc failed\n", __func__);
 888                 return ERR_PTR(-ENOMEM);
 889         }
 890
 891         pages = kzalloc(max_pages * sizeof(struct page *), GFP_NOFS);
 892         if (pages == NULL) {
 893                 kfree(dev);
 894                 return ERR_PTR(-ENOMEM);
 895         }
 896         for (i = 0; i < max_pages; i++) {
 897                 pages[i] = alloc_page(GFP_NOFS);
 898                 if (!pages[i]) {
 899                         rv = ERR_PTR(-ENOMEM);
 900                         goto out_free;
 901                 }
 902         }
 903
 904         memcpy(&dev->dev_id, d_id, sizeof(*d_id));
 905         dev->layout_type = LAYOUT_BLOCK_VOLUME;
 906         dev->pages = pages;
 907         dev->pgbase = 0;
 908         dev->pglen = PAGE_SIZE * max_pages;
 909         dev->mincount = 0;
 910
 911         dprintk("%s: dev_id: %s\n", __func__, dev->dev_id.data);
 912         rc = nfs4_proc_getdeviceinfo(server, dev);
 913         dprintk("%s getdevice info returns %d\n", __func__, rc);
 914         if (rc) {
 915                 rv = ERR_PTR(rc);
 916                 goto out_free;
 917         }
 918
 919         rv = nfs4_blk_decode_device(server, dev);
 920  out_free:
 921         for (i = 0; i < max_pages; i++)
 922                 __free_page(pages[i]);
 923         kfree(pages);
 924         kfree(dev);
 925         return rv;
 926 }
 927
 928 static int
 929 bl_set_layoutdriver(struct nfs_server *server, const struct nfs_fh *fh)
 930 {
 931         struct block_mount_id *b_mt_id = NULL;
 932         struct pnfs_devicelist *dlist = NULL;
 933         struct pnfs_block_dev *bdev;
 934         LIST_HEAD(block_disklist);
 935         int status, i;
 936
 937         dprintk("%s enter\n", __func__);
 938
 939         if (server->pnfs_blksize == 0) {
 940                 dprintk("%s Server did not return blksize\n", __func__);
 941                 return -EINVAL;
 942         }
 943         b_mt_id = kzalloc(sizeof(struct block_mount_id), GFP_NOFS);
 944         if (!b_mt_id) {
 945                 status = -ENOMEM;
 946                 goto out_error;
 947         }
 948         /* Initialize nfs4 block layout mount id */
 949         spin_lock_init(&b_mt_id->bm_lock);
 950         INIT_LIST_HEAD(&b_mt_id->bm_devlist);
 951
 952         dlist = kmalloc(sizeof(struct pnfs_devicelist), GFP_NOFS);
 953         if (!dlist) {
 954                 status = -ENOMEM;
 955                 goto out_error;
 956         }
 957         dlist->eof = 0;
 958         while (!dlist->eof) {
 959                 status = nfs4_proc_getdevicelist(server, fh, dlist);
 960                 if (status)
 961                         goto out_error;
 962                 dprintk("%s GETDEVICELIST numdevs=%i, eof=%i\n",
 963                         __func__, dlist->num_devs, dlist->eof);
 964                 for (i = 0; i < dlist->num_devs; i++) {
 965                         bdev = nfs4_blk_get_deviceinfo(server, fh,
 966                                                        &dlist->dev_id[i]);
 967                         if (IS_ERR(bdev)) {
 968                                 status = PTR_ERR(bdev);
 969                                 goto out_error;
 970                         }
 971                         spin_lock(&b_mt_id->bm_lock);
 972                         list_add(&bdev->bm_node, &b_mt_id->bm_devlist);
 973                         spin_unlock(&b_mt_id->bm_lock);
 974                 }
 975         }
 976         dprintk("%s SUCCESS\n", __func__);
 977         server->pnfs_ld_data = b_mt_id;
 978
 979  out_return:
 980         kfree(dlist);
 981         return status;
 982
 983  out_error:
 984         free_blk_mountid(b_mt_id);
 985         goto out_return;
 986 }
 987
 988 static int
 989 bl_clear_layoutdriver(struct nfs_server *server)
 990 {
 991         struct block_mount_id *b_mt_id = server->pnfs_ld_data;
 992
 993         dprintk("%s enter\n", __func__);
 994         free_blk_mountid(b_mt_id);
 995         dprintk("%s RETURNS\n", __func__);
 996         return 0;
 997 }
 998
 999 static const struct nfs_pageio_ops bl_pg_read_ops = {
1000         .pg_init = pnfs_generic_pg_init_read,
1001         .pg_test = pnfs_generic_pg_test,
1002         .pg_doio = pnfs_generic_pg_readpages,
1003 };
1004
1005 static const struct nfs_pageio_ops bl_pg_write_ops = {
1006         .pg_init = pnfs_generic_pg_init_write,
1007         .pg_test = pnfs_generic_pg_test,
1008         .pg_doio = pnfs_generic_pg_writepages,
1009 };
1010
1011 static struct pnfs_layoutdriver_type blocklayout_type = {
1012         .id                             = LAYOUT_BLOCK_VOLUME,
1013         .name                           = "LAYOUT_BLOCK_VOLUME",
1014         .read_pagelist                  = bl_read_pagelist,
1015         .write_pagelist                 = bl_write_pagelist,
1016         .alloc_layout_hdr               = bl_alloc_layout_hdr,
1017         .free_layout_hdr                = bl_free_layout_hdr,
1018         .alloc_lseg                     = bl_alloc_lseg,
1019         .free_lseg                      = bl_free_lseg,
1020         .encode_layoutcommit            = bl_encode_layoutcommit,
1021         .cleanup_layoutcommit           = bl_cleanup_layoutcommit,
1022         .set_layoutdriver               = bl_set_layoutdriver,
1023         .clear_layoutdriver             = bl_clear_layoutdriver,
1024         .pg_read_ops                    = &bl_pg_read_ops,
1025         .pg_write_ops                   = &bl_pg_write_ops,
1026 };
1027
1028 static const struct rpc_pipe_ops bl_upcall_ops = {
1029         .upcall         = rpc_pipe_generic_upcall,
1030         .downcall       = bl_pipe_downcall,
1031         .destroy_msg    = bl_pipe_destroy_msg,
1032 };
1033
1034 static struct dentry *nfs4blocklayout_register_sb(struct super_block *sb,
1035                                             struct rpc_pipe *pipe)
1036 {
1037         struct dentry *dir, *dentry;
1038
1039         dir = rpc_d_lookup_sb(sb, NFS_PIPE_DIRNAME);
1040         if (dir == NULL)
1041                 return ERR_PTR(-ENOENT);
1042         dentry = rpc_mkpipe_dentry(dir, "blocklayout", NULL, pipe);
1043         dput(dir);
1044         return dentry;
1045 }
1046
1047 static void nfs4blocklayout_unregister_sb(struct super_block *sb,
1048                                           struct rpc_pipe *pipe)
1049 {
1050         if (pipe->dentry)
1051                 rpc_unlink(pipe->dentry);
1052 }
1053
1054 static int rpc_pipefs_event(struct notifier_block *nb, unsigned long event,
1055                            void *ptr)
1056 {
1057         struct super_block *sb = ptr;
1058         struct net *net = sb->s_fs_info;
1059         struct nfs_net *nn = net_generic(net, nfs_net_id);
1060         struct dentry *dentry;
1061         int ret = 0;
1062
1063         if (!try_module_get(THIS_MODULE))
1064                 return 0;
1065
1066         if (nn->bl_device_pipe == NULL) {
1067                 module_put(THIS_MODULE);
1068                 return 0;
1069         }
1070
1071         switch (event) {
1072         case RPC_PIPEFS_MOUNT:
1073                 dentry = nfs4blocklayout_register_sb(sb, nn->bl_device_pipe);
1074                 if (IS_ERR(dentry)) {
1075                         ret = PTR_ERR(dentry);
1076                         break;
1077                 }
1078                 nn->bl_device_pipe->dentry = dentry;
1079                 break;
1080         case RPC_PIPEFS_UMOUNT:
1081                 if (nn->bl_device_pipe->dentry)
1082                         nfs4blocklayout_unregister_sb(sb, nn->bl_device_pipe);
1083                 break;
1084         default:
1085                 ret = -ENOTSUPP;
1086                 break;
1087         }
1088         module_put(THIS_MODULE);
1089         return ret;
1090 }
1091
1092 static struct notifier_block nfs4blocklayout_block = {
1093         .notifier_call = rpc_pipefs_event,
1094 };
1095
1096 static struct dentry *nfs4blocklayout_register_net(struct net *net,
1097                                                    struct rpc_pipe *pipe)
1098 {
1099         struct super_block *pipefs_sb;
1100         struct dentry *dentry;
1101
1102         pipefs_sb = rpc_get_sb_net(net);
1103         if (!pipefs_sb)
1104                 return NULL;
1105         dentry = nfs4blocklayout_register_sb(pipefs_sb, pipe);
1106         rpc_put_sb_net(net);
1107         return dentry;
1108 }
1109
1110 static void nfs4blocklayout_unregister_net(struct net *net,
1111                                            struct rpc_pipe *pipe)
1112 {
1113         struct super_block *pipefs_sb;
1114
1115         pipefs_sb = rpc_get_sb_net(net);
1116         if (pipefs_sb) {
1117                 nfs4blocklayout_unregister_sb(pipefs_sb, pipe);
1118                 rpc_put_sb_net(net);
1119         }
1120 }
1121
1122 static int nfs4blocklayout_net_init(struct net *net)
1123 {
1124         struct nfs_net *nn = net_generic(net, nfs_net_id);
1125         struct dentry *dentry;
1126
1127         init_waitqueue_head(&nn->bl_wq);
1128         nn->bl_device_pipe = rpc_mkpipe_data(&bl_upcall_ops, 0);
1129         if (IS_ERR(nn->bl_device_pipe))
1130                 return PTR_ERR(nn->bl_device_pipe);
1131         dentry = nfs4blocklayout_register_net(net, nn->bl_device_pipe);
1132         if (IS_ERR(dentry)) {
1133                 rpc_destroy_pipe_data(nn->bl_device_pipe);
1134                 return PTR_ERR(dentry);
1135         }
1136         nn->bl_device_pipe->dentry = dentry;
1137         return 0;
1138 }
1139
1140 static void nfs4blocklayout_net_exit(struct net *net)
1141 {
1142         struct nfs_net *nn = net_generic(net, nfs_net_id);
1143
1144         nfs4blocklayout_unregister_net(net, nn->bl_device_pipe);
1145         rpc_destroy_pipe_data(nn->bl_device_pipe);
1146         nn->bl_device_pipe = NULL;
1147 }
1148
1149 static struct pernet_operations nfs4blocklayout_net_ops = {
1150         .init = nfs4blocklayout_net_init,
1151         .exit = nfs4blocklayout_net_exit,
1152 };
1153
1154 static int __init nfs4blocklayout_init(void)
1155 {
1156         int ret;
1157
1158         dprintk("%s: NFSv4 Block Layout Driver Registering...\n", __func__);
1159
1160         ret = pnfs_register_layoutdriver(&blocklayout_type);
1161         if (ret)
1162                 goto out;
1163
1164         ret = rpc_pipefs_notifier_register(&nfs4blocklayout_block);
1165         if (ret)
1166                 goto out_remove;
1167         ret = register_pernet_subsys(&nfs4blocklayout_net_ops);
1168         if (ret)
1169                 goto out_notifier;
1170 out:
1171         return ret;
1172
1173 out_notifier:
1174         rpc_pipefs_notifier_unregister(&nfs4blocklayout_block);
1175 out_remove:
1176         pnfs_unregister_layoutdriver(&blocklayout_type);
1177         return ret;
1178 }
1179
1180 static void __exit nfs4blocklayout_exit(void)
1181 {
1182         dprintk("%s: NFSv4 Block Layout Driver Unregistering...\n",
1183                __func__);
1184
1185         rpc_pipefs_notifier_unregister(&nfs4blocklayout_block);
1186         unregister_pernet_subsys(&nfs4blocklayout_net_ops);
1187         pnfs_unregister_layoutdriver(&blocklayout_type);
1188 }
1189
1190 MODULE_ALIAS("nfs-layouttype4-3");
1191
1192 module_init(nfs4blocklayout_init);
1193 module_exit(nfs4blocklayout_exit);