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 "blocklayout.h"
  42
  43 #define NFSDBG_FACILITY NFSDBG_PNFS_LD
  44
  45 MODULE_LICENSE("GPL");
  46 MODULE_AUTHOR("Andy Adamson <andros@citi.umich.edu>");
  47 MODULE_DESCRIPTION("The NFSv4.1 pNFS Block layout driver");
  48
  49 struct dentry *bl_device_pipe;
  50 wait_queue_head_t bl_wq;
  51
  52 static void print_page(struct page *page)
  53 {
  54         dprintk("PRINTPAGE page %p\n", page);
  55         dprintk("       PagePrivate %d\n", PagePrivate(page));
  56         dprintk("       PageUptodate %d\n", PageUptodate(page));
  57         dprintk("       PageError %d\n", PageError(page));
  58         dprintk("       PageDirty %d\n", PageDirty(page));
  59         dprintk("       PageReferenced %d\n", PageReferenced(page));
  60         dprintk("       PageLocked %d\n", PageLocked(page));
  61         dprintk("       PageWriteback %d\n", PageWriteback(page));
  62         dprintk("       PageMappedToDisk %d\n", PageMappedToDisk(page));
  63         dprintk("\n");
  64 }
  65
  66 /* Given the be associated with isect, determine if page data needs to be
  67  * initialized.
  68  */
  69 static int is_hole(struct pnfs_block_extent *be, sector_t isect)
  70 {
  71         if (be->be_state == PNFS_BLOCK_NONE_DATA)
  72                 return 1;
  73         else if (be->be_state != PNFS_BLOCK_INVALID_DATA)
  74                 return 0;
  75         else
  76                 return !bl_is_sector_init(be->be_inval, isect);
  77 }
  78
  79 /* Given the be associated with isect, determine if page data can be
  80  * written to disk.
  81  */
  82 static int is_writable(struct pnfs_block_extent *be, sector_t isect)
  83 {
  84         return (be->be_state == PNFS_BLOCK_READWRITE_DATA ||
  85                 be->be_state == PNFS_BLOCK_INVALID_DATA);
  86 }
  87
  88 /* The data we are handed might be spread across several bios.  We need
  89  * to track when the last one is finished.
  90  */
  91 struct parallel_io {
  92         struct kref refcnt;
  93         struct rpc_call_ops call_ops;
  94         void (*pnfs_callback) (void *data);
  95         void *data;
  96 };
  97
  98 static inline struct parallel_io *alloc_parallel(void *data)
  99 {
 100         struct parallel_io *rv;
 101
 102         rv  = kmalloc(sizeof(*rv), GFP_NOFS);
 103         if (rv) {
 104                 rv->data = data;
 105                 kref_init(&rv->refcnt);
 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);
 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         bio = bio_alloc(GFP_NOIO, npg);
 150         if (!bio)
 151                 return NULL;
 152
 153         bio->bi_sector = isect - be->be_f_offset + be->be_v_offset;
 154         bio->bi_bdev = be->be_mdev;
 155         bio->bi_end_io = end_io;
 156         bio->bi_private = par;
 157         return bio;
 158 }
 159
 160 static struct bio *bl_add_page_to_bio(struct bio *bio, int npg, int rw,
 161                                       sector_t isect, struct page *page,
 162                                       struct pnfs_block_extent *be,
 163                                       void (*end_io)(struct bio *, int err),
 164                                       struct parallel_io *par)
 165 {
 166 retry:
 167         if (!bio) {
 168                 bio = bl_alloc_init_bio(npg, isect, be, end_io, par);
 169                 if (!bio)
 170                         return ERR_PTR(-ENOMEM);
 171         }
 172         if (bio_add_page(bio, page, PAGE_CACHE_SIZE, 0) < PAGE_CACHE_SIZE) {
 173                 bio = bl_submit_bio(rw, bio);
 174                 goto retry;
 175         }
 176         return bio;
 177 }
 178
 179 /* This is basically copied from mpage_end_io_read */
 180 static void bl_end_io_read(struct bio *bio, int err)
 181 {
 182         struct parallel_io *par = bio->bi_private;
 183         const int uptodate = test_bit(BIO_UPTODATE, &bio->bi_flags);
 184         struct bio_vec *bvec = bio->bi_io_vec + bio->bi_vcnt - 1;
 185         struct nfs_read_data *rdata = (struct nfs_read_data *)par->data;
 186
 187         do {
 188                 struct page *page = bvec->bv_page;
 189
 190                 if (--bvec >= bio->bi_io_vec)
 191                         prefetchw(&bvec->bv_page->flags);
 192                 if (uptodate)
 193                         SetPageUptodate(page);
 194         } while (bvec >= bio->bi_io_vec);
 195         if (!uptodate) {
 196                 if (!rdata->pnfs_error)
 197                         rdata->pnfs_error = -EIO;
 198                 pnfs_set_lo_fail(rdata->lseg);
 199         }
 200         bio_put(bio);
 201         put_parallel(par);
 202 }
 203
 204 static void bl_read_cleanup(struct work_struct *work)
 205 {
 206         struct rpc_task *task;
 207         struct nfs_read_data *rdata;
 208         dprintk("%s enter\n", __func__);
 209         task = container_of(work, struct rpc_task, u.tk_work);
 210         rdata = container_of(task, struct nfs_read_data, task);
 211         pnfs_ld_read_done(rdata);
 212 }
 213
 214 static void
 215 bl_end_par_io_read(void *data)
 216 {
 217         struct nfs_read_data *rdata = data;
 218
 219         INIT_WORK(&rdata->task.u.tk_work, bl_read_cleanup);
 220         schedule_work(&rdata->task.u.tk_work);
 221 }
 222
 223 /* We don't want normal .rpc_call_done callback used, so we replace it
 224  * with this stub.
 225  */
 226 static void bl_rpc_do_nothing(struct rpc_task *task, void *calldata)
 227 {
 228         return;
 229 }
 230
 231 static enum pnfs_try_status
 232 bl_read_pagelist(struct nfs_read_data *rdata)
 233 {
 234         int i, hole;
 235         struct bio *bio = NULL;
 236         struct pnfs_block_extent *be = NULL, *cow_read = NULL;
 237         sector_t isect, extent_length = 0;
 238         struct parallel_io *par;
 239         loff_t f_offset = rdata->args.offset;
 240         size_t count = rdata->args.count;
 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 %Zd\n", __func__,
 245                rdata->npages, f_offset, count);
 246
 247         par = alloc_parallel(rdata);
 248         if (!par)
 249                 goto use_mds;
 250         par->call_ops = *rdata->mds_ops;
 251         par->call_ops.rpc_call_done = bl_rpc_do_nothing;
 252         par->pnfs_callback = bl_end_par_io_read;
 253         /* At this point, we can no longer jump to use_mds */
 254
 255         isect = (sector_t) (f_offset >> SECTOR_SHIFT);
 256         /* Code assumes extents are page-aligned */
 257         for (i = pg_index; i < rdata->npages; i++) {
 258                 if (!extent_length) {
 259                         /* We've used up the previous extent */
 260                         bl_put_extent(be);
 261                         bl_put_extent(cow_read);
 262                         bio = bl_submit_bio(READ, bio);
 263                         /* Get the next one */
 264                         be = bl_find_get_extent(BLK_LSEG2EXT(rdata->lseg),
 265                                              isect, &cow_read);
 266                         if (!be) {
 267                                 rdata->pnfs_error = -EIO;
 268                                 goto out;
 269                         }
 270                         extent_length = be->be_length -
 271                                 (isect - be->be_f_offset);
 272                         if (cow_read) {
 273                                 sector_t cow_length = cow_read->be_length -
 274                                         (isect - cow_read->be_f_offset);
 275                                 extent_length = min(extent_length, cow_length);
 276                         }
 277                 }
 278                 hole = is_hole(be, isect);
 279                 if (hole && !cow_read) {
 280                         bio = bl_submit_bio(READ, bio);
 281                         /* Fill hole w/ zeroes w/o accessing device */
 282                         dprintk("%s Zeroing page for hole\n", __func__);
 283                         zero_user_segment(pages[i], 0, PAGE_CACHE_SIZE);
 284                         print_page(pages[i]);
 285                         SetPageUptodate(pages[i]);
 286                 } else {
 287                         struct pnfs_block_extent *be_read;
 288
 289                         be_read = (hole && cow_read) ? cow_read : be;
 290                         bio = bl_add_page_to_bio(bio, rdata->npages - i, READ,
 291                                                  isect, pages[i], be_read,
 292                                                  bl_end_io_read, par);
 293                         if (IS_ERR(bio)) {
 294                                 rdata->pnfs_error = PTR_ERR(bio);
 295                                 bio = NULL;
 296                                 goto out;
 297                         }
 298                 }
 299                 isect += PAGE_CACHE_SECTORS;
 300                 extent_length -= PAGE_CACHE_SECTORS;
 301         }
 302         if ((isect << SECTOR_SHIFT) >= rdata->inode->i_size) {
 303                 rdata->res.eof = 1;
 304                 rdata->res.count = rdata->inode->i_size - f_offset;
 305         } else {
 306                 rdata->res.count = (isect << SECTOR_SHIFT) - f_offset;
 307         }
 308 out:
 309         bl_put_extent(be);
 310         bl_put_extent(cow_read);
 311         bl_submit_bio(READ, bio);
 312         put_parallel(par);
 313         return PNFS_ATTEMPTED;
 314
 315  use_mds:
 316         dprintk("Giving up and using normal NFS\n");
 317         return PNFS_NOT_ATTEMPTED;
 318 }
 319
 320 static void mark_extents_written(struct pnfs_block_layout *bl,
 321                                  __u64 offset, __u32 count)
 322 {
 323         sector_t isect, end;
 324         struct pnfs_block_extent *be;
 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                         bl_mark_for_commit(be, isect, len); /* What if fails? */
 339                 isect += len;
 340                 bl_put_extent(be);
 341         }
 342 }
 343
 344 static void bl_end_io_write_zero(struct bio *bio, int err)
 345 {
 346         struct parallel_io *par = bio->bi_private;
 347         const int uptodate = test_bit(BIO_UPTODATE, &bio->bi_flags);
 348         struct bio_vec *bvec = bio->bi_io_vec + bio->bi_vcnt - 1;
 349         struct nfs_write_data *wdata = (struct nfs_write_data *)par->data;
 350
 351         do {
 352                 struct page *page = bvec->bv_page;
 353
 354                 if (--bvec >= bio->bi_io_vec)
 355                         prefetchw(&bvec->bv_page->flags);
 356                 /* This is the zeroing page we added */
 357                 end_page_writeback(page);
 358                 page_cache_release(page);
 359         } while (bvec >= bio->bi_io_vec);
 360         if (!uptodate) {
 361                 if (!wdata->pnfs_error)
 362                         wdata->pnfs_error = -EIO;
 363                 pnfs_set_lo_fail(wdata->lseg);
 364         }
 365         bio_put(bio);
 366         put_parallel(par);
 367 }
 368
 369 /* This is basically copied from mpage_end_io_read */
 370 static void bl_end_io_write(struct bio *bio, int err)
 371 {
 372         struct parallel_io *par = bio->bi_private;
 373         const int uptodate = test_bit(BIO_UPTODATE, &bio->bi_flags);
 374         struct nfs_write_data *wdata = (struct nfs_write_data *)par->data;
 375
 376         if (!uptodate) {
 377                 if (!wdata->pnfs_error)
 378                         wdata->pnfs_error = -EIO;
 379                 pnfs_set_lo_fail(wdata->lseg);
 380         }
 381         bio_put(bio);
 382         put_parallel(par);
 383 }
 384
 385 /* Function scheduled for call during bl_end_par_io_write,
 386  * it marks sectors as written and extends the commitlist.
 387  */
 388 static void bl_write_cleanup(struct work_struct *work)
 389 {
 390         struct rpc_task *task;
 391         struct nfs_write_data *wdata;
 392         dprintk("%s enter\n", __func__);
 393         task = container_of(work, struct rpc_task, u.tk_work);
 394         wdata = container_of(task, struct nfs_write_data, task);
 395         if (!wdata->pnfs_error) {
 396                 /* Marks for LAYOUTCOMMIT */
 397                 mark_extents_written(BLK_LSEG2EXT(wdata->lseg),
 398                                      wdata->args.offset, wdata->args.count);
 399         }
 400         pnfs_ld_write_done(wdata);
 401 }
 402
 403 /* Called when last of bios associated with a bl_write_pagelist call finishes */
 404 static void bl_end_par_io_write(void *data)
 405 {
 406         struct nfs_write_data *wdata = data;
 407
 408         wdata->task.tk_status = 0;
 409         wdata->verf.committed = NFS_FILE_SYNC;
 410         INIT_WORK(&wdata->task.u.tk_work, bl_write_cleanup);
 411         schedule_work(&wdata->task.u.tk_work);
 412 }
 413
 414 /* FIXME STUB - mark intersection of layout and page as bad, so is not
 415  * used again.
 416  */
 417 static void mark_bad_read(void)
 418 {
 419         return;
 420 }
 421
 422 /*
 423  * map_block:  map a requested I/0 block (isect) into an offset in the LVM
 424  * block_device
 425  */
 426 static void
 427 map_block(struct buffer_head *bh, sector_t isect, struct pnfs_block_extent *be)
 428 {
 429         dprintk("%s enter be=%p\n", __func__, be);
 430
 431         set_buffer_mapped(bh);
 432         bh->b_bdev = be->be_mdev;
 433         bh->b_blocknr = (isect - be->be_f_offset + be->be_v_offset) >>
 434             (be->be_mdev->bd_inode->i_blkbits - SECTOR_SHIFT);
 435
 436         dprintk("%s isect %llu, bh->b_blocknr %ld, using bsize %Zd\n",
 437                 __func__, (unsigned long long)isect, (long)bh->b_blocknr,
 438                 bh->b_size);
 439         return;
 440 }
 441
 442 /* Given an unmapped page, zero it or read in page for COW, page is locked
 443  * by caller.
 444  */
 445 static int
 446 init_page_for_write(struct page *page, struct pnfs_block_extent *cow_read)
 447 {
 448         struct buffer_head *bh = NULL;
 449         int ret = 0;
 450         sector_t isect;
 451
 452         dprintk("%s enter, %p\n", __func__, page);
 453         BUG_ON(PageUptodate(page));
 454         if (!cow_read) {
 455                 zero_user_segment(page, 0, PAGE_SIZE);
 456                 SetPageUptodate(page);
 457                 goto cleanup;
 458         }
 459
 460         bh = alloc_page_buffers(page, PAGE_CACHE_SIZE, 0);
 461         if (!bh) {
 462                 ret = -ENOMEM;
 463                 goto cleanup;
 464         }
 465
 466         isect = (sector_t) page->index << PAGE_CACHE_SECTOR_SHIFT;
 467         map_block(bh, isect, cow_read);
 468         if (!bh_uptodate_or_lock(bh))
 469                 ret = bh_submit_read(bh);
 470         if (ret)
 471                 goto cleanup;
 472         SetPageUptodate(page);
 473
 474 cleanup:
 475         bl_put_extent(cow_read);
 476         if (bh)
 477                 free_buffer_head(bh);
 478         if (ret) {
 479                 /* Need to mark layout with bad read...should now
 480                  * just use nfs4 for reads and writes.
 481                  */
 482                 mark_bad_read();
 483         }
 484         return ret;
 485 }
 486
 487 static enum pnfs_try_status
 488 bl_write_pagelist(struct nfs_write_data *wdata, int sync)
 489 {
 490         int i, ret, npg_zero, pg_index, last = 0;
 491         struct bio *bio = NULL;
 492         struct pnfs_block_extent *be = NULL, *cow_read = NULL;
 493         sector_t isect, last_isect = 0, extent_length = 0;
 494         struct parallel_io *par;
 495         loff_t offset = wdata->args.offset;
 496         size_t count = wdata->args.count;
 497         struct page **pages = wdata->args.pages;
 498         struct page *page;
 499         pgoff_t index;
 500         u64 temp;
 501         int npg_per_block =
 502             NFS_SERVER(wdata->inode)->pnfs_blksize >> PAGE_CACHE_SHIFT;
 503
 504         dprintk("%s enter, %Zu@%lld\n", __func__, count, offset);
 505         /* At this point, wdata->pages is a (sequential) list of nfs_pages.
 506          * We want to write each, and if there is an error set pnfs_error
 507          * to have it redone using nfs.
 508          */
 509         par = alloc_parallel(wdata);
 510         if (!par)
 511                 return PNFS_NOT_ATTEMPTED;
 512         par->call_ops = *wdata->mds_ops;
 513         par->call_ops.rpc_call_done = bl_rpc_do_nothing;
 514         par->pnfs_callback = bl_end_par_io_write;
 515         /* At this point, have to be more careful with error handling */
 516
 517         isect = (sector_t) ((offset & (long)PAGE_CACHE_MASK) >> SECTOR_SHIFT);
 518         be = bl_find_get_extent(BLK_LSEG2EXT(wdata->lseg), isect, &cow_read);
 519         if (!be || !is_writable(be, isect)) {
 520                 dprintk("%s no matching extents!\n", __func__);
 521                 wdata->pnfs_error = -EINVAL;
 522                 goto out;
 523         }
 524
 525         /* First page inside INVALID extent */
 526         if (be->be_state == PNFS_BLOCK_INVALID_DATA) {
 527                 temp = offset >> PAGE_CACHE_SHIFT;
 528                 npg_zero = do_div(temp, npg_per_block);
 529                 isect = (sector_t) (((offset - npg_zero * PAGE_CACHE_SIZE) &
 530                                      (long)PAGE_CACHE_MASK) >> SECTOR_SHIFT);
 531                 extent_length = be->be_length - (isect - be->be_f_offset);
 532
 533 fill_invalid_ext:
 534                 dprintk("%s need to zero %d pages\n", __func__, npg_zero);
 535                 for (;npg_zero > 0; npg_zero--) {
 536                         if (bl_is_sector_init(be->be_inval, isect)) {
 537                                 dprintk("isect %llu already init\n",
 538                                         (unsigned long long)isect);
 539                                 goto next_page;
 540                         }
 541                         /* page ref released in bl_end_io_write_zero */
 542                         index = isect >> PAGE_CACHE_SECTOR_SHIFT;
 543                         dprintk("%s zero %dth page: index %lu isect %llu\n",
 544                                 __func__, npg_zero, index,
 545                                 (unsigned long long)isect);
 546                         page =
 547                             find_or_create_page(wdata->inode->i_mapping, index,
 548                                                 GFP_NOFS);
 549                         if (!page) {
 550                                 dprintk("%s oom\n", __func__);
 551                                 wdata->pnfs_error = -ENOMEM;
 552                                 goto out;
 553                         }
 554
 555                         /* PageDirty: Other will write this out
 556                          * PageWriteback: Other is writing this out
 557                          * PageUptodate: It was read before
 558                          * sector_initialized: already written out
 559                          */
 560                         if (PageDirty(page) || PageWriteback(page)) {
 561                                 print_page(page);
 562                                 unlock_page(page);
 563                                 page_cache_release(page);
 564                                 goto next_page;
 565                         }
 566                         if (!PageUptodate(page)) {
 567                                 /* New page, readin or zero it */
 568                                 init_page_for_write(page, cow_read);
 569                         }
 570                         set_page_writeback(page);
 571                         unlock_page(page);
 572
 573                         ret = bl_mark_sectors_init(be->be_inval, isect,
 574                                                        PAGE_CACHE_SECTORS,
 575                                                        NULL);
 576                         if (unlikely(ret)) {
 577                                 dprintk("%s bl_mark_sectors_init fail %d\n",
 578                                         __func__, ret);
 579                                 end_page_writeback(page);
 580                                 page_cache_release(page);
 581                                 wdata->pnfs_error = ret;
 582                                 goto out;
 583                         }
 584                         bio = bl_add_page_to_bio(bio, npg_zero, WRITE,
 585                                                  isect, page, be,
 586                                                  bl_end_io_write_zero, par);
 587                         if (IS_ERR(bio)) {
 588                                 wdata->pnfs_error = PTR_ERR(bio);
 589                                 bio = NULL;
 590                                 goto out;
 591                         }
 592                         /* FIXME: This should be done in bi_end_io */
 593                         mark_extents_written(BLK_LSEG2EXT(wdata->lseg),
 594                                              page->index << PAGE_CACHE_SHIFT,
 595                                              PAGE_CACHE_SIZE);
 596 next_page:
 597                         isect += PAGE_CACHE_SECTORS;
 598                         extent_length -= PAGE_CACHE_SECTORS;
 599                 }
 600                 if (last)
 601                         goto write_done;
 602         }
 603         bio = bl_submit_bio(WRITE, bio);
 604
 605         /* Middle pages */
 606         pg_index = wdata->args.pgbase >> PAGE_CACHE_SHIFT;
 607         for (i = pg_index; i < wdata->npages; i++) {
 608                 if (!extent_length) {
 609                         /* We've used up the previous extent */
 610                         bl_put_extent(be);
 611                         bio = bl_submit_bio(WRITE, bio);
 612                         /* Get the next one */
 613                         be = bl_find_get_extent(BLK_LSEG2EXT(wdata->lseg),
 614                                              isect, NULL);
 615                         if (!be || !is_writable(be, isect)) {
 616                                 wdata->pnfs_error = -EINVAL;
 617                                 goto out;
 618                         }
 619                         extent_length = be->be_length -
 620                             (isect - be->be_f_offset);
 621                 }
 622                 if (be->be_state == PNFS_BLOCK_INVALID_DATA) {
 623                         ret = bl_mark_sectors_init(be->be_inval, isect,
 624                                                        PAGE_CACHE_SECTORS,
 625                                                        NULL);
 626                         if (unlikely(ret)) {
 627                                 dprintk("%s bl_mark_sectors_init fail %d\n",
 628                                         __func__, ret);
 629                                 wdata->pnfs_error = ret;
 630                                 goto out;
 631                         }
 632                 }
 633                 bio = bl_add_page_to_bio(bio, wdata->npages - i, WRITE,
 634                                          isect, pages[i], be,
 635                                          bl_end_io_write, par);
 636                 if (IS_ERR(bio)) {
 637                         wdata->pnfs_error = PTR_ERR(bio);
 638                         bio = NULL;
 639                         goto out;
 640                 }
 641                 isect += PAGE_CACHE_SECTORS;
 642                 last_isect = isect;
 643                 extent_length -= PAGE_CACHE_SECTORS;
 644         }
 645
 646         /* Last page inside INVALID extent */
 647         if (be->be_state == PNFS_BLOCK_INVALID_DATA) {
 648                 bio = bl_submit_bio(WRITE, bio);
 649                 temp = last_isect >> PAGE_CACHE_SECTOR_SHIFT;
 650                 npg_zero = npg_per_block - do_div(temp, npg_per_block);
 651                 if (npg_zero < npg_per_block) {
 652                         last = 1;
 653                         goto fill_invalid_ext;
 654                 }
 655         }
 656
 657 write_done:
 658         wdata->res.count = (last_isect << SECTOR_SHIFT) - (offset);
 659         if (count < wdata->res.count) {
 660                 wdata->res.count = count;
 661         }
 662 out:
 663         bl_put_extent(be);
 664         bl_submit_bio(WRITE, bio);
 665         put_parallel(par);
 666         return PNFS_ATTEMPTED;
 667 }
 668
 669 /* FIXME - range ignored */
 670 static void
 671 release_extents(struct pnfs_block_layout *bl, struct pnfs_layout_range *range)
 672 {
 673         int i;
 674         struct pnfs_block_extent *be;
 675
 676         spin_lock(&bl->bl_ext_lock);
 677         for (i = 0; i < EXTENT_LISTS; i++) {
 678                 while (!list_empty(&bl->bl_extents[i])) {
 679                         be = list_first_entry(&bl->bl_extents[i],
 680                                               struct pnfs_block_extent,
 681                                               be_node);
 682                         list_del(&be->be_node);
 683                         bl_put_extent(be);
 684                 }
 685         }
 686         spin_unlock(&bl->bl_ext_lock);
 687 }
 688
 689 static void
 690 release_inval_marks(struct pnfs_inval_markings *marks)
 691 {
 692         struct pnfs_inval_tracking *pos, *temp;
 693
 694         list_for_each_entry_safe(pos, temp, &marks->im_tree.mtt_stub, it_link) {
 695                 list_del(&pos->it_link);
 696                 kfree(pos);
 697         }
 698         return;
 699 }
 700
 701 static void bl_free_layout_hdr(struct pnfs_layout_hdr *lo)
 702 {
 703         struct pnfs_block_layout *bl = BLK_LO2EXT(lo);
 704
 705         dprintk("%s enter\n", __func__);
 706         release_extents(bl, NULL);
 707         release_inval_marks(&bl->bl_inval);
 708         kfree(bl);
 709 }
 710
 711 static struct pnfs_layout_hdr *bl_alloc_layout_hdr(struct inode *inode,
 712                                                    gfp_t gfp_flags)
 713 {
 714         struct pnfs_block_layout *bl;
 715
 716         dprintk("%s enter\n", __func__);
 717         bl = kzalloc(sizeof(*bl), gfp_flags);
 718         if (!bl)
 719                 return NULL;
 720         spin_lock_init(&bl->bl_ext_lock);
 721         INIT_LIST_HEAD(&bl->bl_extents[0]);
 722         INIT_LIST_HEAD(&bl->bl_extents[1]);
 723         INIT_LIST_HEAD(&bl->bl_commit);
 724         INIT_LIST_HEAD(&bl->bl_committing);
 725         bl->bl_count = 0;
 726         bl->bl_blocksize = NFS_SERVER(inode)->pnfs_blksize >> SECTOR_SHIFT;
 727         BL_INIT_INVAL_MARKS(&bl->bl_inval, bl->bl_blocksize);
 728         return &bl->bl_layout;
 729 }
 730
 731 static void bl_free_lseg(struct pnfs_layout_segment *lseg)
 732 {
 733         dprintk("%s enter\n", __func__);
 734         kfree(lseg);
 735 }
 736
 737 /* We pretty much ignore lseg, and store all data layout wide, so we
 738  * can correctly merge.
 739  */
 740 static struct pnfs_layout_segment *bl_alloc_lseg(struct pnfs_layout_hdr *lo,
 741                                                  struct nfs4_layoutget_res *lgr,
 742                                                  gfp_t gfp_flags)
 743 {
 744         struct pnfs_layout_segment *lseg;
 745         int status;
 746
 747         dprintk("%s enter\n", __func__);
 748         lseg = kzalloc(sizeof(*lseg), gfp_flags);
 749         if (!lseg)
 750                 return ERR_PTR(-ENOMEM);
 751         status = nfs4_blk_process_layoutget(lo, lgr, gfp_flags);
 752         if (status) {
 753                 /* We don't want to call the full-blown bl_free_lseg,
 754                  * since on error extents were not touched.
 755                  */
 756                 kfree(lseg);
 757                 return ERR_PTR(status);
 758         }
 759         return lseg;
 760 }
 761
 762 static void
 763 bl_encode_layoutcommit(struct pnfs_layout_hdr *lo, struct xdr_stream *xdr,
 764                        const struct nfs4_layoutcommit_args *arg)
 765 {
 766         dprintk("%s enter\n", __func__);
 767         encode_pnfs_block_layoutupdate(BLK_LO2EXT(lo), xdr, arg);
 768 }
 769
 770 static void
 771 bl_cleanup_layoutcommit(struct nfs4_layoutcommit_data *lcdata)
 772 {
 773         struct pnfs_layout_hdr *lo = NFS_I(lcdata->args.inode)->layout;
 774
 775         dprintk("%s enter\n", __func__);
 776         clean_pnfs_block_layoutupdate(BLK_LO2EXT(lo), &lcdata->args, lcdata->res.status);
 777 }
 778
 779 static void free_blk_mountid(struct block_mount_id *mid)
 780 {
 781         if (mid) {
 782                 struct pnfs_block_dev *dev;
 783                 spin_lock(&mid->bm_lock);
 784                 while (!list_empty(&mid->bm_devlist)) {
 785                         dev = list_first_entry(&mid->bm_devlist,
 786                                                struct pnfs_block_dev,
 787                                                bm_node);
 788                         list_del(&dev->bm_node);
 789                         bl_free_block_dev(dev);
 790                 }
 791                 spin_unlock(&mid->bm_lock);
 792                 kfree(mid);
 793         }
 794 }
 795
 796 /* This is mostly copied from the filelayout's get_device_info function.
 797  * It seems much of this should be at the generic pnfs level.
 798  */
 799 static struct pnfs_block_dev *
 800 nfs4_blk_get_deviceinfo(struct nfs_server *server, const struct nfs_fh *fh,
 801                         struct nfs4_deviceid *d_id)
 802 {
 803         struct pnfs_device *dev;
 804         struct pnfs_block_dev *rv;
 805         u32 max_resp_sz;
 806         int max_pages;
 807         struct page **pages = NULL;
 808         int i, rc;
 809
 810         /*
 811          * Use the session max response size as the basis for setting
 812          * GETDEVICEINFO's maxcount
 813          */
 814         max_resp_sz = server->nfs_client->cl_session->fc_attrs.max_resp_sz;
 815         max_pages = max_resp_sz >> PAGE_SHIFT;
 816         dprintk("%s max_resp_sz %u max_pages %d\n",
 817                 __func__, max_resp_sz, max_pages);
 818
 819         dev = kmalloc(sizeof(*dev), GFP_NOFS);
 820         if (!dev) {
 821                 dprintk("%s kmalloc failed\n", __func__);
 822                 return ERR_PTR(-ENOMEM);
 823         }
 824
 825         pages = kzalloc(max_pages * sizeof(struct page *), GFP_NOFS);
 826         if (pages == NULL) {
 827                 kfree(dev);
 828                 return ERR_PTR(-ENOMEM);
 829         }
 830         for (i = 0; i < max_pages; i++) {
 831                 pages[i] = alloc_page(GFP_NOFS);
 832                 if (!pages[i]) {
 833                         rv = ERR_PTR(-ENOMEM);
 834                         goto out_free;
 835                 }
 836         }
 837
 838         memcpy(&dev->dev_id, d_id, sizeof(*d_id));
 839         dev->layout_type = LAYOUT_BLOCK_VOLUME;
 840         dev->pages = pages;
 841         dev->pgbase = 0;
 842         dev->pglen = PAGE_SIZE * max_pages;
 843         dev->mincount = 0;
 844
 845         dprintk("%s: dev_id: %s\n", __func__, dev->dev_id.data);
 846         rc = nfs4_proc_getdeviceinfo(server, dev);
 847         dprintk("%s getdevice info returns %d\n", __func__, rc);
 848         if (rc) {
 849                 rv = ERR_PTR(rc);
 850                 goto out_free;
 851         }
 852
 853         rv = nfs4_blk_decode_device(server, dev);
 854  out_free:
 855         for (i = 0; i < max_pages; i++)
 856                 __free_page(pages[i]);
 857         kfree(pages);
 858         kfree(dev);
 859         return rv;
 860 }
 861
 862 static int
 863 bl_set_layoutdriver(struct nfs_server *server, const struct nfs_fh *fh)
 864 {
 865         struct block_mount_id *b_mt_id = NULL;
 866         struct pnfs_devicelist *dlist = NULL;
 867         struct pnfs_block_dev *bdev;
 868         LIST_HEAD(block_disklist);
 869         int status, i;
 870
 871         dprintk("%s enter\n", __func__);
 872
 873         if (server->pnfs_blksize == 0) {
 874                 dprintk("%s Server did not return blksize\n", __func__);
 875                 return -EINVAL;
 876         }
 877         b_mt_id = kzalloc(sizeof(struct block_mount_id), GFP_NOFS);
 878         if (!b_mt_id) {
 879                 status = -ENOMEM;
 880                 goto out_error;
 881         }
 882         /* Initialize nfs4 block layout mount id */
 883         spin_lock_init(&b_mt_id->bm_lock);
 884         INIT_LIST_HEAD(&b_mt_id->bm_devlist);
 885
 886         dlist = kmalloc(sizeof(struct pnfs_devicelist), GFP_NOFS);
 887         if (!dlist) {
 888                 status = -ENOMEM;
 889                 goto out_error;
 890         }
 891         dlist->eof = 0;
 892         while (!dlist->eof) {
 893                 status = nfs4_proc_getdevicelist(server, fh, dlist);
 894                 if (status)
 895                         goto out_error;
 896                 dprintk("%s GETDEVICELIST numdevs=%i, eof=%i\n",
 897                         __func__, dlist->num_devs, dlist->eof);
 898                 for (i = 0; i < dlist->num_devs; i++) {
 899                         bdev = nfs4_blk_get_deviceinfo(server, fh,
 900                                                        &dlist->dev_id[i]);
 901                         if (IS_ERR(bdev)) {
 902                                 status = PTR_ERR(bdev);
 903                                 goto out_error;
 904                         }
 905                         spin_lock(&b_mt_id->bm_lock);
 906                         list_add(&bdev->bm_node, &b_mt_id->bm_devlist);
 907                         spin_unlock(&b_mt_id->bm_lock);
 908                 }
 909         }
 910         dprintk("%s SUCCESS\n", __func__);
 911         server->pnfs_ld_data = b_mt_id;
 912
 913  out_return:
 914         kfree(dlist);
 915         return status;
 916
 917  out_error:
 918         free_blk_mountid(b_mt_id);
 919         goto out_return;
 920 }
 921
 922 static int
 923 bl_clear_layoutdriver(struct nfs_server *server)
 924 {
 925         struct block_mount_id *b_mt_id = server->pnfs_ld_data;
 926
 927         dprintk("%s enter\n", __func__);
 928         free_blk_mountid(b_mt_id);
 929         dprintk("%s RETURNS\n", __func__);
 930         return 0;
 931 }
 932
 933 static const struct nfs_pageio_ops bl_pg_read_ops = {
 934         .pg_init = pnfs_generic_pg_init_read,
 935         .pg_test = pnfs_generic_pg_test,
 936         .pg_doio = pnfs_generic_pg_readpages,
 937 };
 938
 939 static const struct nfs_pageio_ops bl_pg_write_ops = {
 940         .pg_init = pnfs_generic_pg_init_write,
 941         .pg_test = pnfs_generic_pg_test,
 942         .pg_doio = pnfs_generic_pg_writepages,
 943 };
 944
 945 static struct pnfs_layoutdriver_type blocklayout_type = {
 946         .id                             = LAYOUT_BLOCK_VOLUME,
 947         .name                           = "LAYOUT_BLOCK_VOLUME",
 948         .read_pagelist                  = bl_read_pagelist,
 949         .write_pagelist                 = bl_write_pagelist,
 950         .alloc_layout_hdr               = bl_alloc_layout_hdr,
 951         .free_layout_hdr                = bl_free_layout_hdr,
 952         .alloc_lseg                     = bl_alloc_lseg,
 953         .free_lseg                      = bl_free_lseg,
 954         .encode_layoutcommit            = bl_encode_layoutcommit,
 955         .cleanup_layoutcommit           = bl_cleanup_layoutcommit,
 956         .set_layoutdriver               = bl_set_layoutdriver,
 957         .clear_layoutdriver             = bl_clear_layoutdriver,
 958         .pg_read_ops                    = &bl_pg_read_ops,
 959         .pg_write_ops                   = &bl_pg_write_ops,
 960 };
 961
 962 static const struct rpc_pipe_ops bl_upcall_ops = {
 963         .upcall         = rpc_pipe_generic_upcall,
 964         .downcall       = bl_pipe_downcall,
 965         .destroy_msg    = bl_pipe_destroy_msg,
 966 };
 967
 968 static int __init nfs4blocklayout_init(void)
 969 {
 970         struct vfsmount *mnt;
 971         struct path path;
 972         int ret;
 973
 974         dprintk("%s: NFSv4 Block Layout Driver Registering...\n", __func__);
 975
 976         ret = pnfs_register_layoutdriver(&blocklayout_type);
 977         if (ret)
 978                 goto out;
 979
 980         init_waitqueue_head(&bl_wq);
 981
 982         mnt = rpc_get_mount();
 983         if (IS_ERR(mnt)) {
 984                 ret = PTR_ERR(mnt);
 985                 goto out_remove;
 986         }
 987
 988         ret = vfs_path_lookup(mnt->mnt_root,
 989                               mnt,
 990                               NFS_PIPE_DIRNAME, 0, &path);
 991         if (ret)
 992                 goto out_putrpc;
 993
 994         bl_device_pipe = rpc_mkpipe(path.dentry, "blocklayout", NULL,
 995                                     &bl_upcall_ops, 0);
 996         path_put(&path);
 997         if (IS_ERR(bl_device_pipe)) {
 998                 ret = PTR_ERR(bl_device_pipe);
 999                 goto out_putrpc;
1000         }
1001 out:
1002         return ret;
1003
1004 out_putrpc:
1005         rpc_put_mount();
1006 out_remove:
1007         pnfs_unregister_layoutdriver(&blocklayout_type);
1008         return ret;
1009 }
1010
1011 static void __exit nfs4blocklayout_exit(void)
1012 {
1013         dprintk("%s: NFSv4 Block Layout Driver Unregistering...\n",
1014                __func__);
1015
1016         pnfs_unregister_layoutdriver(&blocklayout_type);
1017         rpc_unlink(bl_device_pipe);
1018         rpc_put_mount();
1019 }
1020
1021 MODULE_ALIAS("nfs-layouttype4-3");
1022
1023 module_init(nfs4blocklayout_init);
1024 module_exit(nfs4blocklayout_exit);