Whamcloud - gitweb
LU-14423 osd: recognize holes in osd_is_mapped()
[fs/lustre-release.git] / lustre / osd-ldiskfs / osd_io.c
index 913fac8..f99f625 100644 (file)
@@ -38,6 +38,8 @@
  *
  */
 
+#define DEBUG_SUBSYSTEM        S_OSD
+
 /* prerequisite for linux/xattr.h */
 #include <linux/types.h>
 /* prerequisite for linux/xattr.h */
@@ -100,12 +102,12 @@ static int __osd_init_iobuf(struct osd_device *d, struct osd_iobuf *iobuf,
                i <<= 1;
 
        CDEBUG(D_OTHER, "realloc %u for %u (%u) pages\n",
-              (unsigned)(pages * sizeof(iobuf->dr_pages[0])), i, pages);
+              (unsigned int)(pages * sizeof(iobuf->dr_pages[0])), i, pages);
        pages = i;
        blocks = pages * (PAGE_SIZE >> osd_sb(d)->s_blocksize_bits);
        iobuf->dr_max_pages = 0;
        CDEBUG(D_OTHER, "realloc %u for %u blocks\n",
-              (unsigned)(blocks * sizeof(iobuf->dr_blocks[0])), blocks);
+              (unsigned int)(blocks * sizeof(iobuf->dr_blocks[0])), blocks);
 
        lu_buf_realloc(&iobuf->dr_bl_buf, blocks * sizeof(iobuf->dr_blocks[0]));
        iobuf->dr_blocks = iobuf->dr_bl_buf.lb_buf;
@@ -141,24 +143,23 @@ static void osd_iobuf_add_page(struct osd_iobuf *iobuf,
 
 void osd_fini_iobuf(struct osd_device *d, struct osd_iobuf *iobuf)
 {
-        int rw = iobuf->dr_rw;
-
-        if (iobuf->dr_elapsed_valid) {
-                iobuf->dr_elapsed_valid = 0;
-                LASSERT(iobuf->dr_dev == d);
-                LASSERT(iobuf->dr_frags > 0);
-                lprocfs_oh_tally(&d->od_brw_stats.
-                                 hist[BRW_R_DIO_FRAGS+rw],
-                                 iobuf->dr_frags);
+       int rw = iobuf->dr_rw;
+
+       if (iobuf->dr_elapsed_valid) {
+               iobuf->dr_elapsed_valid = 0;
+               LASSERT(iobuf->dr_dev == d);
+               LASSERT(iobuf->dr_frags > 0);
+               lprocfs_oh_tally(&d->od_brw_stats.hist[BRW_R_DIO_FRAGS+rw],
+                                iobuf->dr_frags);
                lprocfs_oh_tally_log2(&d->od_brw_stats.hist[BRW_R_IO_TIME+rw],
                                      ktime_to_ms(iobuf->dr_elapsed));
-        }
+       }
 }
 
 #ifdef HAVE_BIO_ENDIO_USES_ONE_ARG
 static void dio_complete_routine(struct bio *bio)
 {
-       int error = bio->bi_status;
+       int error = blk_status_to_errno(bio->bi_status);
 #else
 static void dio_complete_routine(struct bio *bio, int error)
 {
@@ -166,18 +167,12 @@ static void dio_complete_routine(struct bio *bio, int error)
        struct osd_iobuf *iobuf = bio->bi_private;
        struct bio_vec *bvl;
 
-        /* CAVEAT EMPTOR: possibly in IRQ context
-         * DO NOT record procfs stats here!!! */
+       /* CAVEAT EMPTOR: possibly in IRQ context
+        * DO NOT record procfs stats here!!!
+        */
 
        if (unlikely(iobuf == NULL)) {
-               CERROR("***** bio->bi_private is NULL!  This should never "
-                      "happen.  Normally, I would crash here, but instead I "
-                      "will dump the bio contents to the console.  Please "
-                      "report this to <https://jira.whamcloud.com/> , along "
-                      "with any interesting messages leading up to this point "
-                      "(like SCSI errors, perhaps).  Because bi_private is "
-                      "NULL, I can't wake up the thread that initiated this "
-                      "IO - you will probably have to reboot this node.\n");
+               CERROR("***** bio->bi_private is NULL!  This should never happen.  Normally, I would crash here, but instead I will dump the bio contents to the console.  Please report this to <https://jira.whamcloud.com/> , along with any interesting messages leading up to this point (like SCSI errors, perhaps).  Because bi_private is NULL, I can't wake up the thread that initiated this IO - you will probably have to reboot this node.\n");
                CERROR("bi_next: %p, bi_flags: %lx, " __stringify(bi_opf)
                       ": %x, bi_vcnt: %d, bi_idx: %d, bi->size: %d, bi_end_io: %p, bi_cnt: %d, bi_private: %p\n",
                       bio->bi_next, (unsigned long)bio->bi_flags,
@@ -226,7 +221,8 @@ static void dio_complete_routine(struct bio *bio, int error)
         * filter_clear_dreq().  It was then possible to exhaust the biovec-256
         * mempool when serious on-disk fragmentation was encountered,
         * deadlocking the OST.  The bios are now released as soon as complete
-        * so the pool cannot be exhausted while IOs are competing. bug 10076 */
+        * so the pool cannot be exhausted while IOs are competing. b=10076
+        */
        bio_put(bio);
 }
 
@@ -306,9 +302,8 @@ static int bio_dif_compare(__u16 *expected_guard_buf, void *bio_prot_buf,
        for (i = 0; i < sectors; i++) {
                bio_guard = (__u16 *)bio_prot_buf;
                if (*bio_guard != *expected_guard) {
-                       CERROR("unexpected guard tags on sector %d "
-                              "expected guard %u, bio guard "
-                              "%u, sectors %u, tuple size %d\n",
+                       CERROR(
+                              "unexpected guard tags on sector %d expected guard %u, bio guard %u, sectors %u, tuple size %d\n",
                               i, *expected_guard, *bio_guard, sectors,
                               tuple_size);
                        return -EIO;
@@ -445,14 +440,37 @@ static int osd_bio_init(struct bio *bio, struct osd_iobuf *iobuf,
        RETURN(0);
 }
 
+static void osd_mark_page_io_done(struct osd_iobuf *iobuf,
+                                 struct inode *inode,
+                                 sector_t start_blocks,
+                                 sector_t count)
+{
+       struct niobuf_local *lnb;
+       int blocks_per_page = PAGE_SIZE >> inode->i_blkbits;
+       pgoff_t pg_start, pg_end;
+
+       pg_start = start_blocks / blocks_per_page;
+       if (start_blocks % blocks_per_page)
+               pg_start++;
+       if (count >= blocks_per_page)
+               pg_end = (start_blocks + count -
+                         blocks_per_page) / blocks_per_page;
+       else
+               return; /* nothing to mark */
+       for ( ; pg_start <= pg_end; pg_start++) {
+               lnb = iobuf->dr_lnbs[pg_start];
+               lnb->lnb_flags |= OBD_BRW_DONE;
+       }
+}
+
 static int osd_do_bio(struct osd_device *osd, struct inode *inode,
-                      struct osd_iobuf *iobuf)
+                     struct osd_iobuf *iobuf, sector_t start_blocks,
+                     sector_t count)
 {
        int blocks_per_page = PAGE_SIZE >> inode->i_blkbits;
        struct page **pages = iobuf->dr_pages;
        int npages = iobuf->dr_npages;
        sector_t *blocks = iobuf->dr_blocks;
-       int total_blocks = npages * blocks_per_page;
        struct super_block *sb = inode->i_sb;
        int sector_bits = sb->s_blocksize_bits - 9;
        unsigned int blocksize = sb->s_blocksize;
@@ -464,60 +482,69 @@ static int osd_do_bio(struct osd_device *osd, struct inode *inode,
        unsigned int page_offset;
        sector_t sector;
        int nblocks;
-       int block_idx;
-       int page_idx;
+       int block_idx, block_idx_end;
+       int page_idx, page_idx_start;
        int i;
        int rc = 0;
        bool fault_inject;
        bool integrity_enabled;
        struct blk_plug plug;
+       int blocks_left_page;
+
        ENTRY;
 
        fault_inject = OBD_FAIL_CHECK(OBD_FAIL_OST_INTEGRITY_FAULT);
-        LASSERT(iobuf->dr_npages == npages);
+       LASSERT(iobuf->dr_npages == npages);
 
        integrity_enabled = bdev_integrity_enabled(bdev, iobuf->dr_rw);
 
        osd_brw_stats_update(osd, iobuf);
        iobuf->dr_start_time = ktime_get();
 
+       if (!count)
+               count = npages * blocks_per_page;
+       block_idx_end = start_blocks + count;
+
        blk_start_plug(&plug);
-        for (page_idx = 0, block_idx = 0;
-             page_idx < npages;
-             page_idx++, block_idx += blocks_per_page) {
-
-                page = pages[page_idx];
-                LASSERT(block_idx + blocks_per_page <= total_blocks);
-
-                for (i = 0, page_offset = 0;
-                     i < blocks_per_page;
-                     i += nblocks, page_offset += blocksize * nblocks) {
-
-                        nblocks = 1;
-
-                        if (blocks[block_idx + i] == 0) {  /* hole */
-                                LASSERTF(iobuf->dr_rw == 0,
-                                         "page_idx %u, block_idx %u, i %u\n",
-                                         page_idx, block_idx, i);
-                                memset(kmap(page) + page_offset, 0, blocksize);
-                                kunmap(page);
-                                continue;
-                        }
-
-                        sector = (sector_t)blocks[block_idx + i] << sector_bits;
-
-                        /* Additional contiguous file blocks? */
-                        while (i + nblocks < blocks_per_page &&
-                               (sector + (nblocks << sector_bits)) ==
-                               ((sector_t)blocks[block_idx + i + nblocks] <<
-                                sector_bits))
-                                nblocks++;
-
-                        if (bio != NULL &&
-                            can_be_merged(bio, sector) &&
-                            bio_add_page(bio, page,
-                                         blocksize * nblocks, page_offset) != 0)
-                                continue;       /* added this frag OK */
+
+       page_idx_start = start_blocks / blocks_per_page;
+       for (page_idx = page_idx_start, block_idx = start_blocks;
+            block_idx < block_idx_end; page_idx++,
+            block_idx += blocks_left_page) {
+               page = pages[page_idx];
+               LASSERT(page_idx < iobuf->dr_npages);
+
+               i = block_idx % blocks_per_page;
+               blocks_left_page = blocks_per_page - i;
+               for (page_offset = i * blocksize; i < blocks_left_page;
+                    i += nblocks, page_offset += blocksize * nblocks) {
+                       nblocks = 1;
+
+                       if (blocks[block_idx + i] == 0) {  /* hole */
+                               LASSERTF(iobuf->dr_rw == 0,
+                                        "page_idx %u, block_idx %u, i %u,"
+                                        "start_blocks: %llu, count: %llu, npages: %d\n",
+                                        page_idx, block_idx, i,
+                                        (unsigned long long)start_blocks,
+                                        (unsigned long long)count, npages);
+                               memset(kmap(page) + page_offset, 0, blocksize);
+                               kunmap(page);
+                               continue;
+                       }
+
+                       sector = (sector_t)blocks[block_idx + i] << sector_bits;
+
+                       /* Additional contiguous file blocks? */
+                       while (i + nblocks < blocks_left_page &&
+                              (sector + (nblocks << sector_bits)) ==
+                              ((sector_t)blocks[block_idx + i + nblocks] <<
+                                sector_bits))
+                               nblocks++;
+
+                       if (bio && can_be_merged(bio, sector) &&
+                           bio_add_page(bio, page, blocksize * nblocks,
+                                        page_offset) != 0)
+                               continue;       /* added this frag OK */
 
                        if (bio != NULL) {
                                struct request_queue *q = bio_get_queue(bio);
@@ -529,7 +556,7 @@ static int osd_do_bio(struct osd_device *osd, struct inode *inode,
                                       bi_size, bio->bi_vcnt, bio->bi_max_vecs,
                                       bio_sectors(bio),
                                       queue_max_sectors(q),
-                                      bio->bi_phys_segments,
+                                      osd_bio_nr_segs(bio),
                                       queue_max_segments(q));
                                rc = osd_bio_integrity_handle(osd, bio,
                                        iobuf, bio_start_page_idx,
@@ -546,15 +573,15 @@ static int osd_do_bio(struct osd_device *osd, struct inode *inode,
                        bio_start_page_idx = page_idx;
                        /* allocate new bio */
                        bio = bio_alloc(GFP_NOIO, min(BIO_MAX_PAGES,
-                                                     (npages - page_idx) *
-                                                     blocks_per_page));
-                        if (bio == NULL) {
-                                CERROR("Can't allocate bio %u*%u = %u pages\n",
-                                       (npages - page_idx), blocks_per_page,
-                                       (npages - page_idx) * blocks_per_page);
-                                rc = -ENOMEM;
-                                goto out;
-                        }
+                                       (block_idx_end - block_idx +
+                                        blocks_left_page - 1)));
+                       if (bio == NULL) {
+                               CERROR("Can't allocate bio %u pages\n",
+                                      block_idx_end - block_idx +
+                                      blocks_left_page - 1);
+                               rc = -ENOMEM;
+                               goto out;
+                       }
 
                        bio_set_dev(bio, bdev);
                        bio_set_sector(bio, sector);
@@ -593,7 +620,8 @@ out:
        /* in order to achieve better IO throughput, we don't wait for writes
         * completion here. instead we proceed with transaction commit in
         * parallel and wait for IO completion once transaction is stopped
-        * see osd_trans_stop() for more details -bzzz */
+        * see osd_trans_stop() for more details -bzzz
+        */
        if (iobuf->dr_rw == 0 || fault_inject) {
                wait_event(iobuf->dr_wait,
                           atomic_read(&iobuf->dr_numreqs) == 0);
@@ -607,22 +635,33 @@ out:
                        OBD_FREE_PTR(bio_private);
        }
 
+       /* Write only now */
+       if (rc == 0 && iobuf->dr_rw)
+               osd_mark_page_io_done(iobuf, inode,
+                                     start_blocks, count);
+
        RETURN(rc);
 }
 
 static int osd_map_remote_to_local(loff_t offset, ssize_t len, int *nrpages,
-                                   struct niobuf_local *lnb)
+                                  struct niobuf_local *lnb, int maxlnb)
 {
-        ENTRY;
+       int rc = 0;
+       ENTRY;
 
-        *nrpages = 0;
+       *nrpages = 0;
 
-        while (len > 0) {
+       while (len > 0) {
                int poff = offset & (PAGE_SIZE - 1);
                int plen = PAGE_SIZE - poff;
 
-                if (plen > len)
-                        plen = len;
+               if (*nrpages >= maxlnb) {
+                       rc = -EOVERFLOW;
+                       break;
+               }
+
+               if (plen > len)
+                       plen = len;
                lnb->lnb_file_offset = offset;
                lnb->lnb_page_offset = poff;
                lnb->lnb_len = plen;
@@ -634,64 +673,70 @@ static int osd_map_remote_to_local(loff_t offset, ssize_t len, int *nrpages,
                lnb->lnb_guard_disk = 0;
                lnb->lnb_locked = 0;
 
-                LASSERTF(plen <= len, "plen %u, len %lld\n", plen,
-                         (long long) len);
-                offset += plen;
-                len -= plen;
-                lnb++;
-                (*nrpages)++;
-        }
+               LASSERTF(plen <= len, "plen %u, len %lld\n", plen,
+                        (long long) len);
+               offset += plen;
+               len -= plen;
+               lnb++;
+               (*nrpages)++;
+       }
 
-        RETURN(0);
+       RETURN(rc);
 }
 
 static struct page *osd_get_page(const struct lu_env *env, struct dt_object *dt,
-                                loff_t offset, gfp_t gfp_mask)
+                                loff_t offset, gfp_t gfp_mask, bool cache)
 {
        struct osd_thread_info *oti = osd_oti_get(env);
        struct inode *inode = osd_dt_obj(dt)->oo_inode;
        struct osd_device *d = osd_obj2dev(osd_dt_obj(dt));
        struct page *page;
-       int cur = oti->oti_dio_pages_used;
+       int cur;
 
-        LASSERT(inode);
+       LASSERT(inode);
 
-       if (osd_use_page_cache(d)) {
+       if (cache) {
                page = find_or_create_page(inode->i_mapping,
-                                          offset >> PAGE_SHIFT,
-                                          gfp_mask);
+                                          offset >> PAGE_SHIFT, gfp_mask);
 
-               if (likely(page))
-                       LASSERT(!test_bit(PG_private_2, &page->flags));
-               else
+               if (likely(page)) {
+                       LASSERT(!PagePrivate2(page));
+                       wait_on_page_writeback(page);
+               } else {
                        lprocfs_counter_add(d->od_stats, LPROC_OSD_NO_PAGE, 1);
-       } else {
+               }
 
-               LASSERT(oti->oti_dio_pages);
+               return page;
+       }
 
-               if (unlikely(!oti->oti_dio_pages[cur])) {
-                       LASSERT(cur < PTLRPC_MAX_BRW_PAGES);
-                       page = alloc_page(gfp_mask);
-                       if (!page)
-                               return NULL;
-                       oti->oti_dio_pages[cur] = page;
+       if (inode->i_mapping->nrpages) {
+               /* consult with pagecache, but do not create new pages */
+               /* this is normally used once */
+               page = find_lock_page(inode->i_mapping, offset >> PAGE_SHIFT);
+               if (page) {
+                       wait_on_page_writeback(page);
+                       return page;
                }
+       }
 
-               page = oti->oti_dio_pages[cur];
-               LASSERT(!test_bit(PG_private_2, &page->flags));
-               set_bit(PG_private_2, &page->flags);
-               oti->oti_dio_pages_used++;
-
-               LASSERT(!PageLocked(page));
+       LASSERT(oti->oti_dio_pages);
+       cur = oti->oti_dio_pages_used;
+       page = oti->oti_dio_pages[cur];
+
+       if (unlikely(!page)) {
+               LASSERT(cur < PTLRPC_MAX_BRW_PAGES);
+               page = alloc_page(gfp_mask);
+               if (!page)
+                       return NULL;
+               oti->oti_dio_pages[cur] = page;
+               SetPagePrivate2(page);
                lock_page(page);
-
-               LASSERT(!page->mapping);
-               LASSERT(!PageWriteback(page));
-               ClearPageUptodate(page);
-
-               page->index = offset >> PAGE_SHIFT;
        }
 
+       ClearPageUptodate(page);
+       page->index = offset >> PAGE_SHIFT;
+       oti->oti_dio_pages_used++;
+
        return page;
 }
 
@@ -742,12 +787,9 @@ static int osd_bufs_put(const struct lu_env *env, struct dt_object *dt,
                        continue;
 
                /* if the page isn't cached, then reset uptodate
-                * to prevent reuse */
-               if (test_bit(PG_private_2, &page->flags)) {
-                       clear_bit(PG_private_2, &page->flags);
-                       ClearPageUptodate(page);
-                       if (lnb[i].lnb_locked)
-                               unlock_page(page);
+                * to prevent reuse
+                */
+               if (PagePrivate2(page)) {
                        oti->oti_dio_pages_used--;
                } else {
                        if (lnb[i].lnb_locked)
@@ -755,7 +797,6 @@ static int osd_bufs_put(const struct lu_env *env, struct dt_object *dt,
                        if (pagevec_add(&pvec, page) == 0)
                                pagevec_release(&pvec);
                }
-               dt_object_put(env, dt);
 
                lnb[i].lnb_page = NULL;
        }
@@ -794,41 +835,90 @@ static int osd_bufs_put(const struct lu_env *env, struct dt_object *dt,
  */
 static int osd_bufs_get(const struct lu_env *env, struct dt_object *dt,
                        loff_t pos, ssize_t len, struct niobuf_local *lnb,
-                       enum dt_bufs_type rw)
+                       int maxlnb, enum dt_bufs_type rw)
 {
        struct osd_thread_info *oti = osd_oti_get(env);
        struct osd_object *obj = osd_dt_obj(dt);
-       int npages, i, rc = 0;
+       struct osd_device *osd   = osd_obj2dev(obj);
+       int npages, i, iosize, rc = 0;
+       bool cache, write;
+       loff_t fsize;
        gfp_t gfp_mask;
 
        LASSERT(obj->oo_inode);
 
-       if (!osd_use_page_cache(osd_obj2dev(obj))) {
-               if (unlikely(!oti->oti_dio_pages)) {
-                       OBD_ALLOC(oti->oti_dio_pages,
-                                 sizeof(struct page *) * PTLRPC_MAX_BRW_PAGES);
-                       if (!oti->oti_dio_pages)
-                               return -ENOMEM;
+       rc = osd_map_remote_to_local(pos, len, &npages, lnb, maxlnb);
+       if (rc)
+               RETURN(rc);
+
+       write = rw & DT_BUFS_TYPE_WRITE;
+
+       fsize = lnb[npages - 1].lnb_file_offset + lnb[npages - 1].lnb_len;
+       iosize = fsize - lnb[0].lnb_file_offset;
+       fsize = max(fsize, i_size_read(obj->oo_inode));
+
+       cache = rw & DT_BUFS_TYPE_READAHEAD;
+       if (cache)
+               goto bypass_checks;
+
+       cache = osd_use_page_cache(osd);
+       while (cache) {
+               if (write) {
+                       if (!osd->od_writethrough_cache) {
+                               cache = false;
+                               break;
+                       }
+                       if (iosize > osd->od_writethrough_max_iosize) {
+                               cache = false;
+                               break;
+                       }
+               } else {
+                       if (!osd->od_read_cache) {
+                               cache = false;
+                               break;
+                       }
+                       if (iosize > osd->od_readcache_max_iosize) {
+                               cache = false;
+                               break;
+                       }
                }
+               /* don't use cache on large files */
+               if (osd->od_readcache_max_filesize &&
+                   fsize > osd->od_readcache_max_filesize)
+                       cache = false;
+               break;
        }
 
-       osd_map_remote_to_local(pos, len, &npages, lnb);
+bypass_checks:
+       if (!cache && unlikely(!oti->oti_dio_pages)) {
+               OBD_ALLOC_PTR_ARRAY_LARGE(oti->oti_dio_pages,
+                                         PTLRPC_MAX_BRW_PAGES);
+               if (!oti->oti_dio_pages)
+                       return -ENOMEM;
+       }
 
        /* this could also try less hard for DT_BUFS_TYPE_READAHEAD pages */
        gfp_mask = rw & DT_BUFS_TYPE_LOCAL ? (GFP_NOFS | __GFP_HIGHMEM) :
                                             GFP_HIGHUSER;
        for (i = 0; i < npages; i++, lnb++) {
                lnb->lnb_page = osd_get_page(env, dt, lnb->lnb_file_offset,
-                                            gfp_mask);
+                                            gfp_mask, cache);
                if (lnb->lnb_page == NULL)
                        GOTO(cleanup, rc = -ENOMEM);
 
                lnb->lnb_locked = 1;
-               wait_on_page_writeback(lnb->lnb_page);
-               BUG_ON(PageWriteback(lnb->lnb_page));
+       }
 
-               lu_object_get(&dt->do_lu);
+#if 0
+       /* XXX: this version doesn't invalidate cached pages, but use them */
+       if (!cache && write && obj->oo_inode->i_mapping->nrpages) {
+               /* do not allow data aliasing, invalidate pagecache */
+               /* XXX: can be quite expensive in mixed case */
+               invalidate_mapping_pages(obj->oo_inode->i_mapping,
+                               lnb[0].lnb_file_offset >> PAGE_SHIFT,
+                               lnb[npages - 1].lnb_file_offset >> PAGE_SHIFT);
        }
+#endif
 
        RETURN(i);
 
@@ -837,17 +927,148 @@ cleanup:
                osd_bufs_put(env, dt, lnb - i, i);
        return rc;
 }
+/* Borrow @ext4_chunk_trans_blocks */
+static int osd_chunk_trans_blocks(struct inode *inode, int nrblocks)
+{
+       ldiskfs_group_t groups;
+       int gdpblocks;
+       int idxblocks;
+       int depth;
+       int ret;
+
+       depth = ext_depth(inode);
+       idxblocks = depth * 2;
+
+       /*
+        * Now let's see how many group bitmaps and group descriptors need
+        * to account.
+        */
+       groups = idxblocks + 1;
+       gdpblocks = groups;
+       if (groups > LDISKFS_SB(inode->i_sb)->s_groups_count)
+               groups = LDISKFS_SB(inode->i_sb)->s_groups_count;
+       if (gdpblocks > LDISKFS_SB(inode->i_sb)->s_gdb_count)
+               gdpblocks = LDISKFS_SB(inode->i_sb)->s_gdb_count;
+
+       /* bitmaps and block group descriptor blocks */
+       ret = idxblocks + groups + gdpblocks;
+
+       /* Blocks for super block, inode, quota and xattr blocks */
+       ret += LDISKFS_META_TRANS_BLOCKS(inode->i_sb);
+
+       return ret;
+}
 
-static int osd_ldiskfs_map_inode_pages(struct inode *inode, struct page **page,
-                                      int pages, sector_t *blocks,
-                                      int create)
+#ifdef HAVE_LDISKFS_JOURNAL_ENSURE_CREDITS
+static int osd_extend_restart_trans(handle_t *handle, int needed,
+                                   struct inode *inode)
+{
+       int rc;
+
+       rc = ldiskfs_journal_ensure_credits(handle, needed,
+               ldiskfs_trans_default_revoke_credits(inode->i_sb));
+       /* this means journal has been restarted */
+       if (rc > 0)
+               rc = 0;
+
+       return rc;
+}
+#else
+static int osd_extend_restart_trans(handle_t *handle, int needed,
+                                   struct inode *inode)
+{
+       int rc;
+
+       if (ldiskfs_handle_has_enough_credits(handle, needed))
+               return 0;
+       rc = ldiskfs_journal_extend(handle,
+                               needed - handle->h_buffer_credits);
+       if (rc <= 0)
+               return rc;
+
+       return ldiskfs_journal_restart(handle, needed);
+}
+#endif /* HAVE_LDISKFS_JOURNAL_ENSURE_CREDITS */
+
+static int osd_ldiskfs_map_write(struct inode *inode, struct osd_iobuf *iobuf,
+                                struct osd_device *osd, sector_t start_blocks,
+                                sector_t count, loff_t *disk_size,
+                                __u64 user_size)
+{
+       /* if file has grown, take user_size into account */
+       if (user_size && *disk_size > user_size)
+               *disk_size = user_size;
+
+       spin_lock(&inode->i_lock);
+       if (*disk_size > i_size_read(inode)) {
+               i_size_write(inode, *disk_size);
+               LDISKFS_I(inode)->i_disksize = *disk_size;
+               spin_unlock(&inode->i_lock);
+               osd_dirty_inode(inode, I_DIRTY_DATASYNC);
+       } else {
+               spin_unlock(&inode->i_lock);
+       }
+
+       /*
+        * We don't do stats here as in read path because
+        * write is async: we'll do this in osd_put_bufs()
+        */
+       return osd_do_bio(osd, inode, iobuf, start_blocks, count);
+}
+
+static unsigned int osd_extent_bytes(const struct osd_device *o)
+{
+       unsigned int *extent_bytes_ptr =
+                       raw_cpu_ptr(o->od_extent_bytes_percpu);
+
+       if (likely(*extent_bytes_ptr))
+               return *extent_bytes_ptr;
+
+       /* initialize on first access or CPU hotplug */
+       if (!ldiskfs_has_feature_extents(osd_sb(o)))
+               *extent_bytes_ptr = 1 << osd_sb(o)->s_blocksize_bits;
+       else
+               *extent_bytes_ptr = OSD_DEFAULT_EXTENT_BYTES;
+
+       return *extent_bytes_ptr;
+}
+
+#define EXTENT_BYTES_DECAY 64
+static void osd_decay_extent_bytes(struct osd_device *osd,
+                                  unsigned int new_bytes)
+{
+       unsigned int old_bytes;
+
+       if (!ldiskfs_has_feature_extents(osd_sb(osd)))
+               return;
+
+       old_bytes = osd_extent_bytes(osd);
+       *raw_cpu_ptr(osd->od_extent_bytes_percpu) =
+               (old_bytes * (EXTENT_BYTES_DECAY - 1) +
+                min(new_bytes, OSD_DEFAULT_EXTENT_BYTES) +
+                EXTENT_BYTES_DECAY - 1) / EXTENT_BYTES_DECAY;
+}
+
+static int osd_ldiskfs_map_inode_pages(struct inode *inode,
+                                      struct osd_iobuf *iobuf,
+                                      struct osd_device *osd,
+                                      int create, __u64 user_size,
+                                      int check_credits,
+                                      struct thandle *thandle)
 {
        int blocks_per_page = PAGE_SIZE >> inode->i_blkbits;
-       int rc = 0, i = 0;
+       int rc = 0, i = 0, mapped_index = 0;
        struct page *fp = NULL;
        int clen = 0;
        pgoff_t max_page_index;
        handle_t *handle = NULL;
+       sector_t start_blocks = 0, count = 0;
+       loff_t disk_size = 0;
+       struct page **page = iobuf->dr_pages;
+       int pages = iobuf->dr_npages;
+       sector_t *blocks = iobuf->dr_blocks;
+       struct niobuf_local *lnb1, *lnb2;
+       loff_t size1, size2;
 
        max_page_index = inode->i_sb->s_maxbytes >> PAGE_SHIFT;
 
@@ -861,11 +1082,18 @@ static int osd_ldiskfs_map_inode_pages(struct inode *inode, struct page **page,
                rc = osd_attach_jinode(inode);
                if (rc)
                        return rc;
+               disk_size = i_size_read(inode);
+               /* if disk_size is already bigger than specified user_size,
+                * ignore user_size
+                */
+               if (disk_size > user_size)
+                       user_size = 0;
        }
        /* pages are sorted already. so, we just have to find
-        * contig. space and process them properly */
+        * contig. space and process them properly
+        */
        while (i < pages) {
-               long blen, total = 0;
+               long blen, total = 0, previous_total = 0;
                struct ldiskfs_map_blocks map = { 0 };
 
                if (fp == NULL) { /* start new extent */
@@ -886,61 +1114,136 @@ static int osd_ldiskfs_map_inode_pages(struct inode *inode, struct page **page,
                map.m_lblk = fp->index * blocks_per_page;
                map.m_len = blen = clen * blocks_per_page;
 cont_map:
+               /**
+                * We might restart transaction for block allocations,
+                * in order to make sure data ordered mode, issue IO, disk
+                * size update and block allocations need be within same
+                * transaction to make sure consistency.
+                */
+               if (handle && check_credits) {
+                       struct osd_thandle *oh;
+
+                       LASSERT(thandle != NULL);
+                       oh = container_of(thandle, struct osd_thandle,
+                                         ot_super);
+                       /*
+                        * only issue IO if restart transaction needed,
+                        * as update disk size need hold inode lock, we
+                        * want to avoid that as much as possible.
+                        */
+                       if (oh->oh_declared_ext <= 0) {
+                               rc = osd_ldiskfs_map_write(inode,
+                                       iobuf, osd, start_blocks,
+                                       count, &disk_size, user_size);
+                               if (rc)
+                                       GOTO(cleanup, rc);
+                               thandle->th_restart_tran = 1;
+                               GOTO(cleanup, rc = -EAGAIN);
+                       }
+
+                       if (OBD_FAIL_CHECK(OBD_FAIL_OST_RESTART_IO))
+                               oh->oh_declared_ext = 0;
+                       else
+                               oh->oh_declared_ext--;
+               }
                rc = ldiskfs_map_blocks(handle, inode, &map, create);
                if (rc >= 0) {
                        int c = 0;
+
                        for (; total < blen && c < map.m_len; c++, total++) {
                                if (rc == 0) {
                                        *(blocks + total) = 0;
                                        total++;
                                        break;
-                               } else {
-                                       *(blocks + total) = map.m_pblk + c;
-                                       /* unmap any possible underlying
-                                        * metadata from the block device
-                                        * mapping.  bug 6998. */
-                                       if ((map.m_flags & LDISKFS_MAP_NEW) &&
-                                           create)
-                                               clean_bdev_aliases(
-                                                       inode->i_sb->s_bdev,
-                                                       map.m_pblk + c, 1);
                                }
+                               if ((map.m_flags & LDISKFS_MAP_UNWRITTEN) &&
+                                   !create) {
+                                       /* don't try to read allocated, but
+                                        * unwritten blocks, instead fill the
+                                        * patches with zeros in osd_do_bio() */
+                                       *(blocks + total) = 0;
+                                       continue;
+                               }
+                               *(blocks + total) = map.m_pblk + c;
+                               /* unmap any possible underlying
+                                * metadata from the block device
+                                * mapping.  b=6998.
+                                */
+                               if ((map.m_flags & LDISKFS_MAP_NEW) &&
+                                   create)
+                                       clean_bdev_aliases(inode->i_sb->s_bdev,
+                                                          map.m_pblk + c, 1);
                        }
                        rc = 0;
                }
+
+               if (rc == 0 && create) {
+                       count += (total - previous_total);
+                       mapped_index = (count + blocks_per_page -
+                                       1) / blocks_per_page - 1;
+                       lnb1 = iobuf->dr_lnbs[i - clen];
+                       lnb2 = iobuf->dr_lnbs[mapped_index];
+                       size1 = lnb1->lnb_file_offset -
+                               (lnb1->lnb_file_offset % PAGE_SIZE) +
+                               (total << inode->i_blkbits);
+                       size2 = lnb2->lnb_file_offset + lnb2->lnb_len;
+
+                       if (size1 > size2)
+                               size1 = size2;
+                       if (size1 > disk_size)
+                               disk_size = size1;
+               }
+
                if (rc == 0 && total < blen) {
+                       /*
+                        * decay extent blocks if we could not
+                        * allocate extent once.
+                        */
+                       osd_decay_extent_bytes(osd,
+                               (total - previous_total) << inode->i_blkbits);
                        map.m_lblk = fp->index * blocks_per_page + total;
                        map.m_len = blen - total;
+                       previous_total = total;
                        goto cont_map;
                }
                if (rc != 0)
                        GOTO(cleanup, rc);
-
+               /*
+                * decay extent blocks if we could allocate
+                * good large(1M) extent.
+                */
+               if (previous_total == 0 &&
+                   total >= OSD_DEFAULT_EXTENT_BYTES >> inode->i_blkbits)
+                       osd_decay_extent_bytes(osd,
+                                              total << inode->i_blkbits);
                /* look for next extent */
                fp = NULL;
                blocks += blocks_per_page * clen;
        }
 cleanup:
+       if (rc == 0 && create &&
+           start_blocks < pages * blocks_per_page) {
+               rc = osd_ldiskfs_map_write(inode, iobuf, osd, start_blocks,
+                                          count, &disk_size, user_size);
+               LASSERT(start_blocks + count == pages * blocks_per_page);
+       }
        return rc;
 }
 
 static int osd_write_prep(const struct lu_env *env, struct dt_object *dt,
-                          struct niobuf_local *lnb, int npages)
+                         struct niobuf_local *lnb, int npages)
 {
-        struct osd_thread_info *oti   = osd_oti_get(env);
-        struct osd_iobuf       *iobuf = &oti->oti_iobuf;
-        struct inode           *inode = osd_dt_obj(dt)->oo_inode;
-        struct osd_device      *osd   = osd_obj2dev(osd_dt_obj(dt));
-       ktime_t start;
-       ktime_t end;
+       struct osd_thread_info *oti   = osd_oti_get(env);
+       struct osd_iobuf       *iobuf = &oti->oti_iobuf;
+       struct inode           *inode = osd_dt_obj(dt)->oo_inode;
+       struct osd_device      *osd   = osd_obj2dev(osd_dt_obj(dt));
+       ktime_t start, end;
        s64 timediff;
-        ssize_t                 isize;
-        __s64                   maxidx;
-        int                     rc = 0;
-        int                     i;
-        int                     cache = 0;
+       ssize_t isize;
+       __s64  maxidx;
+       int i, rc = 0;
 
-        LASSERT(inode);
+       LASSERT(inode);
 
        rc = osd_init_iobuf(osd, iobuf, 0, npages);
        if (unlikely(rc != 0))
@@ -949,18 +1252,9 @@ static int osd_write_prep(const struct lu_env *env, struct dt_object *dt,
        isize = i_size_read(inode);
        maxidx = ((isize + PAGE_SIZE - 1) >> PAGE_SHIFT) - 1;
 
-        if (osd->od_writethrough_cache)
-                cache = 1;
-        if (isize > osd->od_readcache_max_filesize)
-                cache = 0;
-
        start = ktime_get();
        for (i = 0; i < npages; i++) {
 
-               if (cache == 0)
-                       generic_error_remove_page(inode->i_mapping,
-                                                 lnb[i].lnb_page);
-
                /*
                 * till commit the content of the page is undefined
                 * we'll set it uptodate once bulk is done. otherwise
@@ -991,17 +1285,16 @@ static int osd_write_prep(const struct lu_env *env, struct dt_object *dt,
        timediff = ktime_us_delta(end, start);
        lprocfs_counter_add(osd->od_stats, LPROC_OSD_GET_PAGE, timediff);
 
-        if (iobuf->dr_npages) {
-               rc = osd_ldiskfs_map_inode_pages(inode, iobuf->dr_pages,
-                                                iobuf->dr_npages,
-                                                iobuf->dr_blocks, 0);
-                if (likely(rc == 0)) {
-                        rc = osd_do_bio(osd, inode, iobuf);
-                        /* do IO stats for preparation reads */
-                        osd_fini_iobuf(osd, iobuf);
-                }
-        }
-        RETURN(rc);
+       if (iobuf->dr_npages) {
+               rc = osd_ldiskfs_map_inode_pages(inode, iobuf, osd, 0,
+                                                0, 0, NULL);
+               if (likely(rc == 0)) {
+                       rc = osd_do_bio(osd, inode, iobuf, 0, 0);
+                       /* do IO stats for preparation reads */
+                       osd_fini_iobuf(osd, iobuf);
+               }
+       }
+       RETURN(rc);
 }
 
 struct osd_fextent {
@@ -1042,6 +1335,16 @@ static int osd_is_mapped(struct dt_object *dt, __u64 offset,
                return 0;
 
        start = fe.fe_logical >> inode->i_blkbits;
+       if (fei.fi_extents_mapped == 0) {
+               /* a special case - no extent found at this offset and forward.
+                * we can consider this as a hole to EOF. it's safe to cache
+                * as other threads can not allocate/punch blocks this thread
+                * is working on (LDLM). */
+               cached_extent->start = block;
+               cached_extent->end = i_size_read(inode) >> inode->i_blkbits;
+               cached_extent->mapped = 0;
+               return 0;
+       }
 
        if (start > block) {
                cached_extent->start = block;
@@ -1058,42 +1361,40 @@ static int osd_is_mapped(struct dt_object *dt, __u64 offset,
 }
 
 static int osd_declare_write_commit(const struct lu_env *env,
-                                    struct dt_object *dt,
-                                    struct niobuf_local *lnb, int npages,
-                                    struct thandle *handle)
+                                   struct dt_object *dt,
+                                   struct niobuf_local *lnb, int npages,
+                                   struct thandle *handle)
 {
        const struct osd_device *osd = osd_obj2dev(osd_dt_obj(dt));
        struct inode            *inode = osd_dt_obj(dt)->oo_inode;
        struct osd_thandle      *oh;
-       int                     extents = 1;
+       int                     extents = 0;
        int                     depth;
        int                     i;
-       int                     newblocks;
+       int                     newblocks = 0;
        int                     rc = 0;
-       int                     flags = 0;
        int                     credits = 0;
        long long               quota_space = 0;
-       struct osd_fextent      extent = { 0 };
+       struct osd_fextent      mapped = { 0 }, extent = { 0 };
+       enum osd_quota_local_flags local_flags = 0;
        enum osd_qid_declare_flags declare_flags = OSD_QID_BLK;
+       unsigned int            extent_bytes;
        ENTRY;
 
-        LASSERT(handle != NULL);
-        oh = container_of0(handle, struct osd_thandle, ot_super);
-        LASSERT(oh->ot_handle == NULL);
+       LASSERT(handle != NULL);
+       oh = container_of(handle, struct osd_thandle, ot_super);
+       LASSERT(oh->ot_handle == NULL);
 
-        newblocks = npages;
+       /*
+        * We track a decaying average extent blocks per filesystem,
+        * for most of time, it will be 1M, with filesystem becoming
+        * heavily-fragmented, it will be reduced to 4K at the worst.
+        */
+       extent_bytes = osd_extent_bytes(osd);
+       LASSERT(extent_bytes >= (1 << osd_sb(osd)->s_blocksize));
 
-        /* calculate number of extents (probably better to pass nb) */
+       /* calculate number of extents (probably better to pass nb) */
        for (i = 0; i < npages; i++) {
-               if (i && lnb[i].lnb_file_offset !=
-                   lnb[i - 1].lnb_file_offset + lnb[i - 1].lnb_len)
-                       extents++;
-
-               if (osd_is_mapped(dt, lnb[i].lnb_file_offset, &extent))
-                       lnb[i].lnb_flags |= OBD_BRW_MAPPED;
-               else
-                       quota_space += PAGE_SIZE;
-
                /* ignore quota for the whole request if any page is from
                 * client cache or written by root.
                 *
@@ -1102,55 +1403,91 @@ static int osd_declare_write_commit(const struct lu_env *env,
                 * !(lnb[i].flags & OBD_BRW_SYNC)
                 *
                 * XXX we could handle this on per-lnb basis as done by
-                * grant. */
+                * grant.
+                */
                if ((lnb[i].lnb_flags & OBD_BRW_NOQUOTA) ||
                    (lnb[i].lnb_flags & (OBD_BRW_FROM_GRANT | OBD_BRW_SYNC)) ==
                    OBD_BRW_FROM_GRANT)
                        declare_flags |= OSD_QID_FORCE;
+
+               if (osd_is_mapped(dt, lnb[i].lnb_file_offset, &mapped)) {
+                       lnb[i].lnb_flags |= OBD_BRW_MAPPED;
+                       continue;
+               }
+
+               if (lnb[i].lnb_flags & OBD_BRW_DONE) {
+                       lnb[i].lnb_flags |= OBD_BRW_MAPPED;
+                       continue;
+               }
+
+               /* count only unmapped changes */
+               newblocks++;
+               if (lnb[i].lnb_file_offset != extent.end || extent.end == 0) {
+                       if (extent.end != 0)
+                               extents += (extent.end - extent.start +
+                                       extent_bytes - 1) / extent_bytes;
+                       extent.start = lnb[i].lnb_file_offset;
+                       extent.end = lnb[i].lnb_file_offset + lnb[i].lnb_len;
+               } else {
+                       extent.end += lnb[i].lnb_len;
+               }
+
+               quota_space += PAGE_SIZE;
        }
 
-        /*
-         * each extent can go into new leaf causing a split
-         * 5 is max tree depth: inode + 4 index blocks
-         * with blockmaps, depth is 3 at most
-         */
-        if (LDISKFS_I(inode)->i_flags & LDISKFS_EXTENTS_FL) {
-                /*
-                 * many concurrent threads may grow tree by the time
-                 * our transaction starts. so, consider 2 is a min depth
-                 */
-                depth = ext_depth(inode);
-                depth = max(depth, 1) + 1;
-                newblocks += depth;
-               credits++; /* inode */
+       credits++; /* inode */
+       /*
+        * overwrite case, no need to modify tree and
+        * allocate blocks.
+        */
+       if (!newblocks)
+               goto out_declare;
+
+       extents += (extent.end - extent.start +
+                   extent_bytes - 1) / extent_bytes;
+       /*
+        * each extent can go into new leaf causing a split
+        * 5 is max tree depth: inode + 4 index blocks
+        * with blockmaps, depth is 3 at most
+        */
+       if (LDISKFS_I(inode)->i_flags & LDISKFS_EXTENTS_FL) {
+               /*
+                * many concurrent threads may grow tree by the time
+                * our transaction starts. so, consider 2 is a min depth
+                */
+               depth = ext_depth(inode);
+               depth = max(depth, 1) + 1;
+               newblocks += depth;
                credits += depth * 2 * extents;
        } else {
                depth = 3;
                newblocks += depth;
-               credits++; /* inode */
                credits += depth * extents;
        }
 
+       oh->oh_declared_ext = extents;
+
        /* quota space for metadata blocks */
        quota_space += depth * extents * LDISKFS_BLOCK_SIZE(osd_sb(osd));
 
        /* quota space should be reported in 1K blocks */
        quota_space = toqb(quota_space);
 
-        /* each new block can go in different group (bitmap + gd) */
+       /* each new block can go in different group (bitmap + gd) */
 
-        /* we can't dirty more bitmap blocks than exist */
-        if (newblocks > LDISKFS_SB(osd_sb(osd))->s_groups_count)
+       /* we can't dirty more bitmap blocks than exist */
+       if (extents > LDISKFS_SB(osd_sb(osd))->s_groups_count)
                credits += LDISKFS_SB(osd_sb(osd))->s_groups_count;
-        else
-               credits += newblocks;
+       else
+               credits += extents;
 
        /* we can't dirty more gd blocks than exist */
-       if (newblocks > LDISKFS_SB(osd_sb(osd))->s_gdb_count)
+       if (extents > LDISKFS_SB(osd_sb(osd))->s_gdb_count)
                credits += LDISKFS_SB(osd_sb(osd))->s_gdb_count;
        else
-               credits += newblocks;
+               credits += extents;
 
+out_declare:
        osd_trans_declare_op(env, oh, OSD_OT_WRITE, credits);
 
        /* make sure the over quota flags were not set */
@@ -1158,16 +1495,17 @@ static int osd_declare_write_commit(const struct lu_env *env,
 
        rc = osd_declare_inode_qid(env, i_uid_read(inode), i_gid_read(inode),
                                   i_projid_read(inode), quota_space, oh,
-                                  osd_dt_obj(dt), &flags, declare_flags);
+                                  osd_dt_obj(dt), &local_flags, declare_flags);
 
        /* we need only to store the overquota flags in the first lnb for
         * now, once we support multiple objects BRW, this code needs be
-        * revised. */
-       if (flags & QUOTA_FL_OVER_USRQUOTA)
+        * revised.
+        */
+       if (local_flags & QUOTA_FL_OVER_USRQUOTA)
                lnb[0].lnb_flags |= OBD_BRW_OVER_USRQUOTA;
-       if (flags & QUOTA_FL_OVER_GRPQUOTA)
+       if (local_flags & QUOTA_FL_OVER_GRPQUOTA)
                lnb[0].lnb_flags |= OBD_BRW_OVER_GRPQUOTA;
-       if (flags & QUOTA_FL_OVER_PRJQUOTA)
+       if (local_flags & QUOTA_FL_OVER_PRJQUOTA)
                lnb[0].lnb_flags |= OBD_BRW_OVER_PRJQUOTA;
 
        if (rc == 0)
@@ -1178,30 +1516,29 @@ static int osd_declare_write_commit(const struct lu_env *env,
 
 /* Check if a block is allocated or not */
 static int osd_write_commit(const struct lu_env *env, struct dt_object *dt,
-                            struct niobuf_local *lnb, int npages,
-                            struct thandle *thandle)
+                           struct niobuf_local *lnb, int npages,
+                           struct thandle *thandle, __u64 user_size)
 {
-        struct osd_thread_info *oti = osd_oti_get(env);
-        struct osd_iobuf *iobuf = &oti->oti_iobuf;
-        struct inode *inode = osd_dt_obj(dt)->oo_inode;
-        struct osd_device  *osd = osd_obj2dev(osd_dt_obj(dt));
-        loff_t isize;
-        int rc = 0, i;
+       struct osd_thread_info *oti = osd_oti_get(env);
+       struct osd_iobuf *iobuf = &oti->oti_iobuf;
+       struct inode *inode = osd_dt_obj(dt)->oo_inode;
+       struct osd_device  *osd = osd_obj2dev(osd_dt_obj(dt));
+       int rc = 0, i, check_credits = 0;
 
-        LASSERT(inode);
+       LASSERT(inode);
 
        rc = osd_init_iobuf(osd, iobuf, 1, npages);
        if (unlikely(rc != 0))
                RETURN(rc);
 
-       isize = i_size_read(inode);
        dquot_initialize(inode);
 
-        for (i = 0; i < npages; i++) {
+       for (i = 0; i < npages; i++) {
                if (lnb[i].lnb_rc == -ENOSPC &&
                    (lnb[i].lnb_flags & OBD_BRW_MAPPED)) {
                        /* Allow the write to proceed if overwriting an
-                        * existing block */
+                        * existing block
+                        */
                        lnb[i].lnb_rc = 0;
                }
 
@@ -1214,12 +1551,15 @@ static int osd_write_commit(const struct lu_env *env, struct dt_object *dt,
                        continue;
                }
 
+               if (lnb[i].lnb_flags & OBD_BRW_DONE)
+                       continue;
+
+               if (!(lnb[i].lnb_flags & OBD_BRW_MAPPED))
+                       check_credits = 1;
+
                LASSERT(PageLocked(lnb[i].lnb_page));
                LASSERT(!PageWriteback(lnb[i].lnb_page));
 
-               if (lnb[i].lnb_file_offset + lnb[i].lnb_len > isize)
-                       isize = lnb[i].lnb_file_offset + lnb[i].lnb_len;
-
                /*
                 * Since write and truncate are serialized by oo_sem, even
                 * partial-page truncate should not leave dirty pages in the
@@ -1230,49 +1570,37 @@ static int osd_write_commit(const struct lu_env *env, struct dt_object *dt,
                SetPageUptodate(lnb[i].lnb_page);
 
                osd_iobuf_add_page(iobuf, &lnb[i]);
-        }
+       }
 
        osd_trans_exec_op(env, thandle, OSD_OT_WRITE);
 
-        if (OBD_FAIL_CHECK(OBD_FAIL_OST_MAPBLK_ENOSPC)) {
-                rc = -ENOSPC;
-        } else if (iobuf->dr_npages > 0) {
-               rc = osd_ldiskfs_map_inode_pages(inode, iobuf->dr_pages,
-                                                iobuf->dr_npages,
-                                                iobuf->dr_blocks, 1);
-        } else {
-                /* no pages to write, no transno is needed */
-                thandle->th_local = 1;
-        }
-
-       if (likely(rc == 0)) {
-               spin_lock(&inode->i_lock);
-               if (isize > i_size_read(inode)) {
-                       i_size_write(inode, isize);
-                       LDISKFS_I(inode)->i_disksize = isize;
-                       spin_unlock(&inode->i_lock);
-                       ll_dirty_inode(inode, I_DIRTY_DATASYNC);
-               } else {
-                       spin_unlock(&inode->i_lock);
-               }
-
-               rc = osd_do_bio(osd, inode, iobuf);
-               /* we don't do stats here as in read path because
-                * write is async: we'll do this in osd_put_bufs() */
+       if (OBD_FAIL_CHECK(OBD_FAIL_OST_MAPBLK_ENOSPC)) {
+               rc = -ENOSPC;
+       } else if (iobuf->dr_npages > 0) {
+               rc = osd_ldiskfs_map_inode_pages(inode, iobuf, osd,
+                                                1, user_size,
+                                                check_credits,
+                                                thandle);
        } else {
-               osd_fini_iobuf(osd, iobuf);
+               /* no pages to write, no transno is needed */
+               thandle->th_local = 1;
        }
 
+       if (rc != 0 && !thandle->th_restart_tran)
+               osd_fini_iobuf(osd, iobuf);
+
        osd_trans_exec_check(env, thandle, OSD_OT_WRITE);
 
-       if (unlikely(rc != 0)) {
+       if (unlikely(rc != 0 && !thandle->th_restart_tran)) {
                /* if write fails, we should drop pages from the cache */
                for (i = 0; i < npages; i++) {
                        if (lnb[i].lnb_page == NULL)
                                continue;
-                       LASSERT(PageLocked(lnb[i].lnb_page));
-                       generic_error_remove_page(inode->i_mapping,
-                                                 lnb[i].lnb_page);
+                       if (!PagePrivate2(lnb[i].lnb_page)) {
+                               LASSERT(PageLocked(lnb[i].lnb_page));
+                               generic_error_remove_page(inode->i_mapping,
+                                                         lnb[i].lnb_page);
+                       }
                }
        }
 
@@ -1280,18 +1608,18 @@ static int osd_write_commit(const struct lu_env *env, struct dt_object *dt,
 }
 
 static int osd_read_prep(const struct lu_env *env, struct dt_object *dt,
-                         struct niobuf_local *lnb, int npages)
+                        struct niobuf_local *lnb, int npages)
 {
-        struct osd_thread_info *oti = osd_oti_get(env);
-        struct osd_iobuf *iobuf = &oti->oti_iobuf;
-        struct inode *inode = osd_dt_obj(dt)->oo_inode;
-        struct osd_device *osd = osd_obj2dev(osd_dt_obj(dt));
-       int rc = 0, i, cache = 0, cache_hits = 0, cache_misses = 0;
+       struct osd_thread_info *oti = osd_oti_get(env);
+       struct osd_iobuf *iobuf = &oti->oti_iobuf;
+       struct inode *inode = osd_dt_obj(dt)->oo_inode;
+       struct osd_device *osd = osd_obj2dev(osd_dt_obj(dt));
+       int rc = 0, i, cache_hits = 0, cache_misses = 0;
        ktime_t start, end;
        s64 timediff;
        loff_t isize;
 
-        LASSERT(inode);
+       LASSERT(inode);
 
        rc = osd_init_iobuf(osd, iobuf, 0, npages);
        if (unlikely(rc != 0))
@@ -1299,32 +1627,24 @@ static int osd_read_prep(const struct lu_env *env, struct dt_object *dt,
 
        isize = i_size_read(inode);
 
-       if (osd->od_read_cache)
-               cache = 1;
-       if (isize > osd->od_readcache_max_filesize)
-               cache = 0;
-
        start = ktime_get();
        for (i = 0; i < npages; i++) {
 
                if (isize <= lnb[i].lnb_file_offset)
                        /* If there's no more data, abort early.
-                        * lnb->lnb_rc == 0, so it's easy to detect later. */
+                        * lnb->lnb_rc == 0, so it's easy to detect later.
+                        */
                        break;
 
-               if (isize < lnb[i].lnb_file_offset + lnb[i].lnb_len)
-                       lnb[i].lnb_rc = isize - lnb[i].lnb_file_offset;
-               else
-                       lnb[i].lnb_rc = lnb[i].lnb_len;
+               /* instead of looking if we go beyong isize, send complete
+                * pages all the time
+                */
+               lnb[i].lnb_rc = lnb[i].lnb_len;
 
                /* Bypass disk read if fail_loc is set properly */
                if (OBD_FAIL_CHECK(OBD_FAIL_OST_FAKE_RW))
                        SetPageUptodate(lnb[i].lnb_page);
 
-               if (cache == 0)
-                       generic_error_remove_page(inode->i_mapping,
-                                                 lnb[i].lnb_page);
-
                if (PageUptodate(lnb[i].lnb_page)) {
                        cache_hits++;
                        unlock_page(lnb[i].lnb_page);
@@ -1336,7 +1656,8 @@ static int osd_read_prep(const struct lu_env *env, struct dt_object *dt,
                 * unlocked, the earlier another client can access it.
                 * notice real unlock_page() can be called few lines
                 * below after osd_do_bio(). lnb is a per-thread, so it's
-                * fine to have PG_locked and lnb_locked inconsistent here */
+                * fine to have PG_locked and lnb_locked inconsistent here
+                */
                lnb[i].lnb_locked = 0;
        }
        end = ktime_get();
@@ -1354,17 +1675,18 @@ static int osd_read_prep(const struct lu_env *env, struct dt_object *dt,
                                    cache_hits + cache_misses);
 
        if (iobuf->dr_npages) {
-               rc = osd_ldiskfs_map_inode_pages(inode, iobuf->dr_pages,
-                                                iobuf->dr_npages,
-                                                iobuf->dr_blocks, 0);
-               rc = osd_do_bio(osd, inode, iobuf);
+               rc = osd_ldiskfs_map_inode_pages(inode, iobuf, osd, 0,
+                                                0, 0, NULL);
+               if (!rc)
+                       rc = osd_do_bio(osd, inode, iobuf, 0, 0);
 
                /* IO stats will be done in osd_bufs_put() */
 
                /* early release to let others read data during the bulk */
                for (i = 0; i < iobuf->dr_npages; i++) {
                        LASSERT(PageLocked(iobuf->dr_pages[i]));
-                       unlock_page(iobuf->dr_pages[i]);
+                       if (!PagePrivate2(iobuf->dr_pages[i]))
+                               unlock_page(iobuf->dr_pages[i]);
                }
        }
 
@@ -1384,26 +1706,27 @@ static int osd_read_prep(const struct lu_env *env, struct dt_object *dt,
  */
 static int osd_ldiskfs_readlink(struct inode *inode, char *buffer, int buflen)
 {
-        struct ldiskfs_inode_info *ei = LDISKFS_I(inode);
+       struct ldiskfs_inode_info *ei = LDISKFS_I(inode);
 
-        memcpy(buffer, (char *)ei->i_data, buflen);
+       memcpy(buffer, (char *)ei->i_data, buflen);
 
-        return  buflen;
+       return  buflen;
 }
 
 int osd_ldiskfs_read(struct inode *inode, void *buf, int size, loff_t *offs)
 {
-        struct buffer_head *bh;
-        unsigned long block;
-        int osize;
-        int blocksize;
-        int csize;
-        int boffs;
-
-        /* prevent reading after eof */
+       struct buffer_head *bh;
+       unsigned long block;
+       int osize;
+       int blocksize;
+       int csize;
+       int boffs;
+
+       /* prevent reading after eof */
        spin_lock(&inode->i_lock);
        if (i_size_read(inode) < *offs + size) {
                loff_t diff = i_size_read(inode) - *offs;
+
                spin_unlock(&inode->i_lock);
                if (diff < 0) {
                        CDEBUG(D_OTHER,
@@ -1419,17 +1742,16 @@ int osd_ldiskfs_read(struct inode *inode, void *buf, int size, loff_t *offs)
                spin_unlock(&inode->i_lock);
        }
 
-        blocksize = 1 << inode->i_blkbits;
-        osize = size;
-        while (size > 0) {
-                block = *offs >> inode->i_blkbits;
-                boffs = *offs & (blocksize - 1);
-                csize = min(blocksize - boffs, size);
+       blocksize = 1 << inode->i_blkbits;
+       osize = size;
+       while (size > 0) {
+               block = *offs >> inode->i_blkbits;
+               boffs = *offs & (blocksize - 1);
+               csize = min(blocksize - boffs, size);
                bh = __ldiskfs_bread(NULL, inode, block, 0);
                if (IS_ERR(bh)) {
-                       CERROR("%s: can't read %u@%llu on ino %lu: "
-                              "rc = %ld\n", osd_ino2name(inode),
-                              csize, *offs, inode->i_ino,
+                       CERROR("%s: can't read %u@%llu on ino %lu: rc = %ld\n",
+                              osd_ino2name(inode), csize, *offs, inode->i_ino,
                               PTR_ERR(bh));
                        return PTR_ERR(bh);
                }
@@ -1441,29 +1763,37 @@ int osd_ldiskfs_read(struct inode *inode, void *buf, int size, loff_t *offs)
                        memset(buf, 0, csize);
                }
 
-                *offs += csize;
-                buf += csize;
-                size -= csize;
-        }
-        return osize;
+               *offs += csize;
+               buf += csize;
+               size -= csize;
+       }
+       return osize;
 }
 
 static ssize_t osd_read(const struct lu_env *env, struct dt_object *dt,
                        struct lu_buf *buf, loff_t *pos)
 {
-        struct inode *inode = osd_dt_obj(dt)->oo_inode;
-        int           rc;
-
-        /* Read small symlink from inode body as we need to maintain correct
-         * on-disk symlinks for ldiskfs.
-         */
-        if (S_ISLNK(dt->do_lu.lo_header->loh_attr) &&
-            (buf->lb_len < sizeof(LDISKFS_I(inode)->i_data)))
-                rc = osd_ldiskfs_readlink(inode, buf->lb_buf, buf->lb_len);
-        else
-                rc = osd_ldiskfs_read(inode, buf->lb_buf, buf->lb_len, pos);
-
-        return rc;
+       struct inode *inode = osd_dt_obj(dt)->oo_inode;
+       int rc;
+
+       /* Read small symlink from inode body as we need to maintain correct
+        * on-disk symlinks for ldiskfs.
+        */
+       if (S_ISLNK(dt->do_lu.lo_header->loh_attr)) {
+               loff_t size = i_size_read(inode);
+
+               if (buf->lb_len < size)
+                       return -EOVERFLOW;
+
+               if (size < sizeof(LDISKFS_I(inode)->i_data))
+                       rc = osd_ldiskfs_readlink(inode, buf->lb_buf, size);
+               else
+                       rc = osd_ldiskfs_read(inode, buf->lb_buf, size, pos);
+       } else {
+               rc = osd_ldiskfs_read(inode, buf->lb_buf, buf->lb_len, pos);
+       }
+
+       return rc;
 }
 
 static inline int osd_extents_enabled(struct super_block *sb,
@@ -1489,7 +1819,8 @@ int osd_calc_bkmap_credits(struct super_block *sb, struct inode *inode,
 
        /* legacy blockmap: 3 levels * 3 (bitmap,gd,itself)
         * we do not expect blockmaps on the large files,
-        * so let's shrink it to 2 levels (4GB files) */
+        * so let's shrink it to 2 levels (4GB files)
+        */
 
        /* this is default reservation: 2 levels */
        credits = (blocks + 2) * 3;
@@ -1541,10 +1872,10 @@ static ssize_t osd_declare_write(const struct lu_env *env, struct dt_object *dt,
        ENTRY;
 
        LASSERT(buf != NULL);
-        LASSERT(handle != NULL);
+       LASSERT(handle != NULL);
 
-        oh = container_of0(handle, struct osd_thandle, ot_super);
-        LASSERT(oh->ot_handle == NULL);
+       oh = container_of(handle, struct osd_thandle, ot_super);
+       LASSERT(oh->ot_handle == NULL);
 
        size = buf->lb_len;
        bits = sb->s_blocksize_bits;
@@ -1552,7 +1883,8 @@ static ssize_t osd_declare_write(const struct lu_env *env, struct dt_object *dt,
 
        if (_pos == -1) {
                /* if this is an append, then we
-                * should expect cross-block record */
+                * should expect cross-block record
+                */
                pos = 0;
        } else {
                pos = _pos;
@@ -1587,7 +1919,8 @@ static ssize_t osd_declare_write(const struct lu_env *env, struct dt_object *dt,
                depth = max(depth, 1) + 1;
                credits = depth;
                /* if not append, then split may need to modify
-                * existing blocks moving entries into the new ones */
+                * existing blocks moving entries into the new ones
+                */
                if (_pos != -1)
                        credits += depth;
                /* blocks to store data: bitmap,gd,itself */
@@ -1596,7 +1929,8 @@ static ssize_t osd_declare_write(const struct lu_env *env, struct dt_object *dt,
                credits = osd_calc_bkmap_credits(sb, inode, size, _pos, blocks);
        }
        /* if inode is created as part of the transaction,
-        * then it's counted already by the creation method */
+        * then it's counted already by the creation method
+        */
        if (inode != NULL)
                credits++;
 
@@ -1606,7 +1940,8 @@ out:
 
        /* dt_declare_write() is usually called for system objects, such
         * as llog or last_rcvd files. We needn't enforce quota on those
-        * objects, so always set the lqi_space as 0. */
+        * objects, so always set the lqi_space as 0.
+        */
        if (inode != NULL)
                rc = osd_declare_inode_qid(env, i_uid_read(inode),
                                           i_gid_read(inode),
@@ -1629,23 +1964,27 @@ static int osd_ldiskfs_writelink(struct inode *inode, char *buffer, int buflen)
        LDISKFS_I(inode)->i_disksize = buflen;
        i_size_write(inode, buflen);
        spin_unlock(&inode->i_lock);
-       ll_dirty_inode(inode, I_DIRTY_DATASYNC);
+       osd_dirty_inode(inode, I_DIRTY_DATASYNC);
 
        return 0;
 }
 
-int osd_ldiskfs_write_record(struct inode *inode, void *buf, int bufsize,
-                            int write_NUL, loff_t *offs, handle_t *handle)
+static int osd_ldiskfs_write_record(struct dt_object *dt, void *buf,
+                                   int bufsize, int write_NUL, loff_t *offs,
+                                   handle_t *handle)
 {
-        struct buffer_head *bh        = NULL;
-        loff_t              offset    = *offs;
-        loff_t              new_size  = i_size_read(inode);
-        unsigned long       block;
-        int                 blocksize = 1 << inode->i_blkbits;
-        int                 err = 0;
-        int                 size;
-        int                 boffs;
-        int                 dirty_inode = 0;
+       struct inode *inode = osd_dt_obj(dt)->oo_inode;
+       struct buffer_head *bh        = NULL;
+       loff_t              offset    = *offs;
+       loff_t              new_size  = i_size_read(inode);
+       unsigned long       block;
+       int                 blocksize = 1 << inode->i_blkbits;
+       struct ldiskfs_inode_info *ei = LDISKFS_I(inode);
+       int                 err = 0;
+       int                 size;
+       int                 boffs;
+       int                 dirty_inode = 0;
+       bool create, sparse, sync = false;
 
        if (write_NUL) {
                /*
@@ -1657,8 +1996,18 @@ int osd_ldiskfs_write_record(struct inode *inode, void *buf, int bufsize,
                ++bufsize;
        }
 
+       /* only the first flag-set matters */
+       dirty_inode = !test_and_set_bit(LDISKFS_INODE_JOURNAL_DATA,
+                                      &ei->i_flags);
+
+       /* sparse checking is racy, but sparse is very rare case, leave as is */
+       sparse = (new_size > 0 && (inode->i_blocks >> (inode->i_blkbits - 9)) <
+                 ((new_size - 1) >> inode->i_blkbits) + 1);
+
        while (bufsize > 0) {
                int credits = handle->h_buffer_credits;
+               unsigned long last_block = (new_size == 0) ? 0 :
+                                          (new_size - 1) >> inode->i_blkbits;
 
                if (bh)
                        brelse(bh);
@@ -1666,7 +2015,40 @@ int osd_ldiskfs_write_record(struct inode *inode, void *buf, int bufsize,
                block = offset >> inode->i_blkbits;
                boffs = offset & (blocksize - 1);
                size = min(blocksize - boffs, bufsize);
-               bh = __ldiskfs_bread(handle, inode, block, 1);
+               sync = (block > last_block || new_size == 0 || sparse);
+
+               if (sync)
+                       down(&ei->i_append_sem);
+
+               bh = __ldiskfs_bread(handle, inode, block, 0);
+
+               if (unlikely(IS_ERR_OR_NULL(bh) && !sync))
+                       CWARN(
+                             "%s: adding bh without locking off %llu (block %lu, size %d, offs %llu)\n",
+                             osd_ino2name(inode),
+                             offset, block, bufsize, *offs);
+
+               if (IS_ERR_OR_NULL(bh)) {
+                       struct osd_device *osd = osd_obj2dev(osd_dt_obj(dt));
+                       int flags = LDISKFS_GET_BLOCKS_CREATE;
+
+                       /* while the file system is being mounted, avoid
+                        * preallocation otherwise mount can take a long
+                        * time as mballoc cache is cold.
+                        * XXX: this is a workaround until we have a proper
+                        *      fix in mballoc
+                        * XXX: works with extent-based files only */
+                       if (!osd->od_cl_seq)
+                               flags |= LDISKFS_GET_BLOCKS_NO_NORMALIZE;
+                       bh = __ldiskfs_bread(handle, inode, block, flags);
+                       create = true;
+               } else {
+                       if (sync) {
+                               up(&ei->i_append_sem);
+                               sync = false;
+                       }
+                       create = false;
+               }
                if (IS_ERR_OR_NULL(bh)) {
                        if (bh == NULL) {
                                err = -EIO;
@@ -1675,35 +2057,45 @@ int osd_ldiskfs_write_record(struct inode *inode, void *buf, int bufsize,
                                bh = NULL;
                        }
 
-                       CERROR("%s: error reading offset %llu (block %lu, "
-                              "size %d, offs %llu), credits %d/%d: rc = %d\n",
-                              inode->i_sb->s_id, offset, block, bufsize, *offs,
-                              credits, handle->h_buffer_credits, err);
-                        break;
-                }
-
-                err = ldiskfs_journal_get_write_access(handle, bh);
-                if (err) {
-                        CERROR("journal_get_write_access() returned error %d\n",
-                               err);
-                        break;
-                }
+                       CERROR(
+                              "%s: error reading offset %llu (block %lu, size %d, offs %llu), credits %d/%d: rc = %d\n",
+                              osd_ino2name(inode), offset, block, bufsize,
+                              *offs, credits, handle->h_buffer_credits, err);
+                       break;
+               }
+
+               err = ldiskfs_journal_get_write_access(handle, bh);
+               if (err) {
+                       CERROR("journal_get_write_access() returned error %d\n",
+                              err);
+                       break;
+               }
                LASSERTF(boffs + size <= bh->b_size,
                         "boffs %d size %d bh->b_size %lu\n",
                         boffs, size, (unsigned long)bh->b_size);
-                memcpy(bh->b_data + boffs, buf, size);
+               if (create) {
+                       memset(bh->b_data, 0, bh->b_size);
+                       if (sync) {
+                               up(&ei->i_append_sem);
+                               sync = false;
+                       }
+               }
+               memcpy(bh->b_data + boffs, buf, size);
                err = ldiskfs_handle_dirty_metadata(handle, NULL, bh);
-                if (err)
-                        break;
-
-                if (offset + size > new_size)
-                        new_size = offset + size;
-                offset += size;
-                bufsize -= size;
-                buf += size;
-        }
-        if (bh)
-                brelse(bh);
+               if (err)
+                       break;
+
+               if (offset + size > new_size)
+                       new_size = offset + size;
+               offset += size;
+               bufsize -= size;
+               buf += size;
+       }
+       if (sync)
+               up(&ei->i_append_sem);
+
+       if (bh)
+               brelse(bh);
 
        if (write_NUL)
                --new_size;
@@ -1712,18 +2104,18 @@ int osd_ldiskfs_write_record(struct inode *inode, void *buf, int bufsize,
                spin_lock(&inode->i_lock);
                if (new_size > i_size_read(inode))
                        i_size_write(inode, new_size);
-               if (i_size_read(inode) > LDISKFS_I(inode)->i_disksize) {
-                       LDISKFS_I(inode)->i_disksize = i_size_read(inode);
+               if (i_size_read(inode) > ei->i_disksize) {
+                       ei->i_disksize = i_size_read(inode);
                        dirty_inode = 1;
                }
                spin_unlock(&inode->i_lock);
-               if (dirty_inode)
-                       ll_dirty_inode(inode, I_DIRTY_DATASYNC);
-        }
+       }
+       if (dirty_inode)
+               osd_dirty_inode(inode, I_DIRTY_DATASYNC);
 
-        if (err == 0)
-                *offs = offset;
-        return err;
+       if (err == 0)
+               *offs = offset;
+       return err;
 }
 
 static ssize_t osd_write(const struct lu_env *env, struct dt_object *dt,
@@ -1735,17 +2127,17 @@ static ssize_t osd_write(const struct lu_env *env, struct dt_object *dt,
        ssize_t                 result;
        int                     is_link;
 
-        LASSERT(dt_object_exists(dt));
+       LASSERT(dt_object_exists(dt));
 
-        LASSERT(handle != NULL);
+       LASSERT(handle != NULL);
        LASSERT(inode != NULL);
        dquot_initialize(inode);
 
-        /* XXX: don't check: one declared chunk can be used many times */
+       /* XXX: don't check: one declared chunk can be used many times */
        /* osd_trans_exec_op(env, handle, OSD_OT_WRITE); */
 
-        oh = container_of(handle, struct osd_thandle, ot_super);
-        LASSERT(oh->ot_handle->h_transaction != NULL);
+       oh = container_of(handle, struct osd_thandle, ot_super);
+       LASSERT(oh->ot_handle->h_transaction != NULL);
        osd_trans_exec_op(env, handle, OSD_OT_WRITE);
 
        /* Write small symlink to inode body as we need to maintain correct
@@ -1757,9 +2149,8 @@ static ssize_t osd_write(const struct lu_env *env, struct dt_object *dt,
        if (is_link && (buf->lb_len < sizeof(LDISKFS_I(inode)->i_data)))
                result = osd_ldiskfs_writelink(inode, buf->lb_buf, buf->lb_len);
        else
-               result = osd_ldiskfs_write_record(inode, buf->lb_buf,
-                                                 buf->lb_len, is_link, pos,
-                                                 oh->ot_handle);
+               result = osd_ldiskfs_write_record(dt, buf->lb_buf, buf->lb_len,
+                                                 is_link, pos, oh->ot_handle);
        if (result == 0)
                result = buf->lb_len;
 
@@ -1768,25 +2159,199 @@ static ssize_t osd_write(const struct lu_env *env, struct dt_object *dt,
        return result;
 }
 
+static int osd_declare_fallocate(const struct lu_env *env,
+                                struct dt_object *dt, __u64 start, __u64 end,
+                                int mode, struct thandle *th)
+{
+       struct osd_thandle *oh = container_of(th, struct osd_thandle, ot_super);
+       struct osd_device *osd = osd_obj2dev(osd_dt_obj(dt));
+       struct inode *inode = osd_dt_obj(dt)->oo_inode;
+       long long quota_space = 0;
+       /* 5 is max tree depth. (inode + 4 index blocks) */
+       int depth = 5;
+       int rc;
+
+       ENTRY;
+
+       /*
+        * Only mode == 0 (which is standard prealloc) is supported now.
+        * Rest of mode options is not supported yet.
+        */
+       if (mode & ~FALLOC_FL_KEEP_SIZE)
+               RETURN(-EOPNOTSUPP);
+
+       /* disable fallocate completely */
+       if (osd_dev(dt->do_lu.lo_dev)->od_fallocate_zero_blocks < 0)
+               RETURN(-EOPNOTSUPP);
+
+       LASSERT(th);
+       LASSERT(inode);
+
+       /* quota space for metadata blocks
+        * approximate metadata estimate should be good enough.
+        */
+       quota_space += PAGE_SIZE;
+       quota_space += depth * LDISKFS_BLOCK_SIZE(osd_sb(osd));
+
+       /* quota space should be reported in 1K blocks */
+       quota_space = toqb(quota_space) + toqb(end - start) +
+                     LDISKFS_META_TRANS_BLOCKS(inode->i_sb);
+
+       /* We don't need to reserve credits for whole fallocate here.
+        * We reserve space only for metadata. Fallocate credits are
+        * extended as required
+        */
+       rc = osd_declare_inode_qid(env, i_uid_read(inode), i_gid_read(inode),
+                                  i_projid_read(inode), quota_space, oh,
+                                  osd_dt_obj(dt), NULL, OSD_QID_BLK);
+       RETURN(rc);
+}
+
+static int osd_fallocate(const struct lu_env *env, struct dt_object *dt,
+                        __u64 start, __u64 end, int mode, struct thandle *th)
+{
+       struct osd_thandle *oh = container_of(th, struct osd_thandle, ot_super);
+       handle_t *handle = ldiskfs_journal_current_handle();
+       unsigned int save_credits = oh->ot_credits;
+       struct osd_object *obj = osd_dt_obj(dt);
+       struct inode *inode = obj->oo_inode;
+       struct ldiskfs_map_blocks map;
+       unsigned int credits;
+       ldiskfs_lblk_t blen;
+       ldiskfs_lblk_t boff;
+       loff_t new_size = 0;
+       int depth = 0;
+       int flags;
+       int rc = 0;
+
+       ENTRY;
+
+       LASSERT(dt_object_exists(dt));
+       LASSERT(osd_invariant(obj));
+       LASSERT(inode != NULL);
+
+       CDEBUG(D_INODE, "fallocate: inode #%lu: start %llu end %llu mode %d\n",
+              inode->i_ino, start, end, mode);
+
+       dquot_initialize(inode);
+
+       LASSERT(th);
+
+       boff = start >> inode->i_blkbits;
+       blen = (ALIGN(end, 1 << inode->i_blkbits) >> inode->i_blkbits) - boff;
+
+       /* Create and mark new extents as either zero or unwritten */
+       flags = osd_dev(dt->do_lu.lo_dev)->od_fallocate_zero_blocks ?
+               LDISKFS_GET_BLOCKS_CREATE_ZERO :
+               LDISKFS_GET_BLOCKS_CREATE_UNWRIT_EXT;
+       if (mode & FALLOC_FL_KEEP_SIZE)
+               flags |= LDISKFS_GET_BLOCKS_KEEP_SIZE;
+
+       inode_lock(inode);
+
+       /*
+        * We only support preallocation for extent-based file only.
+        */
+       if (!(ldiskfs_test_inode_flag(inode, LDISKFS_INODE_EXTENTS)))
+               GOTO(out, rc = -EOPNOTSUPP);
+
+       if (!(mode & FALLOC_FL_KEEP_SIZE) && (end > i_size_read(inode) ||
+           end > LDISKFS_I(inode)->i_disksize)) {
+               new_size = end;
+               rc = inode_newsize_ok(inode, new_size);
+               if (rc)
+                       GOTO(out, rc);
+       }
+
+       inode_dio_wait(inode);
+
+       map.m_lblk = boff;
+       map.m_len = blen;
+
+       /* Don't normalize the request if it can fit in one extent so
+        * that it doesn't get unnecessarily split into multiple extents.
+        */
+       if (blen <= EXT_UNWRITTEN_MAX_LEN)
+               flags |= LDISKFS_GET_BLOCKS_NO_NORMALIZE;
+
+       /*
+        * credits to insert 1 extent into extent tree.
+        */
+       credits = osd_chunk_trans_blocks(inode, blen);
+       depth = ext_depth(inode);
+
+       while (rc >= 0 && blen) {
+               loff_t epos;
+
+               /*
+                * Recalculate credits when extent tree depth changes.
+                */
+               if (depth != ext_depth(inode)) {
+                       credits = osd_chunk_trans_blocks(inode, blen);
+                       depth = ext_depth(inode);
+               }
+
+               /* TODO: quota check */
+               rc = osd_extend_restart_trans(handle, credits, inode);
+               if (rc)
+                       break;
+
+               rc = ldiskfs_map_blocks(handle, inode, &map, flags);
+               if (rc <= 0) {
+                       CDEBUG(D_INODE,
+                              "inode #%lu: block %u: len %u: ldiskfs_map_blocks returned %d\n",
+                              inode->i_ino, map.m_lblk, map.m_len, rc);
+                       ldiskfs_mark_inode_dirty(handle, inode);
+                       break;
+               }
+
+               map.m_lblk += rc;
+               map.m_len = blen = blen - rc;
+               epos = (loff_t)map.m_lblk << inode->i_blkbits;
+               inode->i_ctime = current_time(inode);
+               if (new_size) {
+                       if (epos > end)
+                               epos = end;
+                       if (ldiskfs_update_inode_size(inode, epos) & 0x1)
+                               inode->i_mtime = inode->i_ctime;
+               } else {
+                       if (epos > inode->i_size)
+                               ldiskfs_set_inode_flag(inode,
+                                                      LDISKFS_INODE_EOFBLOCKS);
+               }
+
+               ldiskfs_mark_inode_dirty(handle, inode);
+       }
+
+out:
+       /* extand credits if needed for operations such as attribute set */
+       if (rc >= 0)
+               rc = osd_extend_restart_trans(handle, save_credits, inode);
+
+       inode_unlock(inode);
+
+       RETURN(rc);
+}
+
 static int osd_declare_punch(const struct lu_env *env, struct dt_object *dt,
-                             __u64 start, __u64 end, struct thandle *th)
+                            __u64 start, __u64 end, struct thandle *th)
 {
-        struct osd_thandle *oh;
+       struct osd_thandle *oh;
        struct inode       *inode;
        int                 rc;
-        ENTRY;
-
-        LASSERT(th);
-        oh = container_of(th, struct osd_thandle, ot_super);
-
-        /*
-         * we don't need to reserve credits for whole truncate
-         * it's not possible as truncate may need to free too many
-         * blocks and that won't fit a single transaction. instead
-         * we reserve credits to change i_size and put inode onto
-         * orphan list. if needed truncate will extend or restart
-         * transaction
-         */
+       ENTRY;
+
+       LASSERT(th);
+       oh = container_of(th, struct osd_thandle, ot_super);
+
+       /*
+        * we don't need to reserve credits for whole truncate
+        * it's not possible as truncate may need to free too many
+        * blocks and that won't fit a single transaction. instead
+        * we reserve credits to change i_size and put inode onto
+        * orphan list. if needed truncate will extend or restart
+        * transaction
+        */
        osd_trans_declare_op(env, oh, OSD_OT_PUNCH,
                             osd_dto_credits_noquota[DTO_ATTR_SET_BASE] + 3);
 
@@ -1815,7 +2380,6 @@ static int osd_punch(const struct lu_env *env, struct dt_object *dt,
        bool grow = false;
        ENTRY;
 
-       LASSERT(end == OBD_OBJECT_EOF);
        LASSERT(dt_object_exists(dt));
        LASSERT(osd_invariant(obj));
        LASSERT(inode != NULL);
@@ -1831,7 +2395,8 @@ static int osd_punch(const struct lu_env *env, struct dt_object *dt,
         * and then get truncate RPC which essentially
         * would be skipped. this is bad.. so, disable
         * this optimization on MDS till the client stop
-        * to sent MDS_REINT (LU-11033) -bzzz */
+        * to sent MDS_REINT (LU-11033) -bzzz
+        */
        if (osd->od_is_ost && i_size_read(inode) == start)
                RETURN(0);
 
@@ -1842,6 +2407,14 @@ static int osd_punch(const struct lu_env *env, struct dt_object *dt,
                grow = true;
        i_size_write(inode, start);
        spin_unlock(&inode->i_lock);
+       /* if object holds encrypted content, we need to make sure we truncate
+        * on an encryption unit boundary, or subsequent reads will get
+        * corrupted content
+        */
+       if (obj->oo_lma_flags & LUSTRE_ENCRYPT_FL &&
+           start & ~LUSTRE_ENCRYPTION_MASK)
+               start = (start & LUSTRE_ENCRYPTION_MASK) +
+                       LUSTRE_ENCRYPTION_UNIT_SIZE;
        ll_truncate_pagecache(inode, start);
 
        /* optimize grow case */
@@ -1850,10 +2423,13 @@ static int osd_punch(const struct lu_env *env, struct dt_object *dt,
                GOTO(out, rc);
        }
 
+       inode_lock(inode);
        /* add to orphan list to ensure truncate completion
         * if this transaction succeed. ldiskfs_truncate()
-        * will take the inode out of the list */
+        * will take the inode out of the list
+        */
        rc = ldiskfs_orphan_add(oh->ot_handle, inode);
+       inode_unlock(inode);
        if (rc != 0)
                GOTO(out, rc);
 
@@ -1947,17 +2523,16 @@ static int osd_fiemap_get(const struct lu_env *env, struct dt_object *dt,
 static int osd_ladvise(const struct lu_env *env, struct dt_object *dt,
                       __u64 start, __u64 end, enum lu_ladvise_type advice)
 {
-       int              rc = 0;
-       struct inode    *inode = osd_dt_obj(dt)->oo_inode;
+       struct osd_object *obj = osd_dt_obj(dt);
+       int rc = 0;
        ENTRY;
 
        switch (advice) {
        case LU_LADVISE_DONTNEED:
-               if (end == 0)
-                       break;
-               invalidate_mapping_pages(inode->i_mapping,
-                                        start >> PAGE_SHIFT,
-                                        (end - 1) >> PAGE_SHIFT);
+               if (end)
+                       invalidate_mapping_pages(obj->oo_inode->i_mapping,
+                                                start >> PAGE_SHIFT,
+                                                (end - 1) >> PAGE_SHIFT);
                break;
        default:
                rc = -ENOTSUPP;
@@ -1967,12 +2542,43 @@ static int osd_ladvise(const struct lu_env *env, struct dt_object *dt,
        RETURN(rc);
 }
 
+static loff_t osd_lseek(const struct lu_env *env, struct dt_object *dt,
+                       loff_t offset, int whence)
+{
+       struct osd_object *obj = osd_dt_obj(dt);
+       struct inode *inode = obj->oo_inode;
+       struct file *file;
+       loff_t result;
+
+       ENTRY;
+
+       LASSERT(dt_object_exists(dt));
+       LASSERT(osd_invariant(obj));
+       LASSERT(inode);
+       LASSERT(offset >= 0);
+
+       file = osd_quasi_file(env, inode);
+       result = file->f_op->llseek(file, offset, whence);
+
+       /*
+        * If 'offset' is beyond end of object file then treat it as not error
+        * but valid case for SEEK_HOLE and return 'offset' as result.
+        * LOV will decide if it is beyond real end of file or not.
+        */
+       if (whence == SEEK_HOLE && result == -ENXIO)
+               result = offset;
+
+       CDEBUG(D_INFO, "seek %s from %lld: %lld\n", whence == SEEK_HOLE ?
+                      "hole" : "data", offset, result);
+       RETURN(result);
+}
+
 /*
  * in some cases we may need declare methods for objects being created
  * e.g., when we create symlink
  */
 const struct dt_body_operations osd_body_ops_new = {
-        .dbo_declare_write = osd_declare_write,
+       .dbo_declare_write = osd_declare_write,
 };
 
 const struct dt_body_operations osd_body_ops = {
@@ -1989,6 +2595,9 @@ const struct dt_body_operations osd_body_ops = {
        .dbo_punch                      = osd_punch,
        .dbo_fiemap_get                 = osd_fiemap_get,
        .dbo_ladvise                    = osd_ladvise,
+       .dbo_declare_fallocate          = osd_declare_fallocate,
+       .dbo_fallocate                  = osd_fallocate,
+       .dbo_lseek                      = osd_lseek,
 };
 
 /**
@@ -2033,20 +2642,23 @@ int osd_trunc_lock(struct osd_object *obj, struct osd_thandle *oh, bool shared)
        else
                down_write(&obj->oo_ext_idx_sem);
        al->tl_shared = shared;
+       lu_object_get(&obj->oo_dt.do_lu);
 
        list_add(&al->tl_list, &oh->ot_trunc_locks);
 
        return 0;
 }
 
-void osd_trunc_unlock_all(struct list_head *list)
+void osd_trunc_unlock_all(const struct lu_env *env, struct list_head *list)
 {
        struct osd_access_lock *al, *tmp;
+
        list_for_each_entry_safe(al, tmp, list, tl_list) {
                if (al->tl_shared)
                        up_read(&al->tl_obj->oo_ext_idx_sem);
                else
                        up_write(&al->tl_obj->oo_ext_idx_sem);
+               osd_object_put(env, al->tl_obj);
                list_del(&al->tl_list);
                OBD_FREE_PTR(al);
        }
@@ -2069,13 +2681,29 @@ void osd_execute_truncate(struct osd_object *obj)
                return;
        }
 
+       size = i_size_read(inode);
+       inode_lock(inode);
+       /* if object holds encrypted content, we need to make sure we truncate
+        * on an encryption unit boundary, or block content will get corrupted
+        */
+       if (obj->oo_lma_flags & LUSTRE_ENCRYPT_FL &&
+           size & ~LUSTRE_ENCRYPTION_MASK)
+               inode->i_size = (size & LUSTRE_ENCRYPTION_MASK) +
+                       LUSTRE_ENCRYPTION_UNIT_SIZE;
        ldiskfs_truncate(inode);
+       inode_unlock(inode);
+       if (inode->i_size != size) {
+               spin_lock(&inode->i_lock);
+               i_size_write(inode, size);
+               LDISKFS_I(inode)->i_disksize = size;
+               spin_unlock(&inode->i_lock);
+               osd_dirty_inode(inode, I_DIRTY_DATASYNC);
+       }
 
        /*
         * For a partial-page truncate, flush the page to disk immediately to
         * avoid data corruption during direct disk write.  b=17397
         */
-       size = i_size_read(inode);
        if ((size & ~PAGE_MASK) == 0)
                return;
        if (osd_use_page_cache(d)) {