21 files changed, 1187 insertions, 167 deletions

diff --git a/Documentation/filesystems/ubifs.txt b/Documentation/filesystems/ubifs.txt
index 6a0d70a22f05..dd84ea3c10da 100644
--- a/Documentation/filesystems/ubifs.txt
+++ b/Documentation/filesystems/ubifs.txt
@@ -86,6 +86,15 @@ norm_unmount (*)	commit on unmount; the journal is committed
 fast_unmount            do not commit on unmount; this option makes
                         unmount faster, but the next mount slower
                         because of the need to replay the journal.
+bulk_read               read more in one go to take advantage of flash
+                        media that read faster sequentially
+no_bulk_read (*)        do not bulk-read
+no_chk_data_crc         skip checking of CRCs on data nodes in order to
+                        improve read performance. Use this option only
+                        if the flash media is highly reliable. The effect
+                        of this option is that corruption of the contents
+                        of a file can go unnoticed.
+chk_data_crc (*)        do not skip checking CRCs on data nodes
 
 
 Quick usage instructions
diff --git a/fs/ubifs/budget.c b/fs/ubifs/budget.c
index 73db464cd08b..1a4973e10664 100644
--- a/fs/ubifs/budget.c
+++ b/fs/ubifs/budget.c
@@ -414,19 +414,21 @@ static int do_budget_space(struct ubifs_info *c)
          *    @c->lst.empty_lebs + @c->freeable_cnt + @c->idx_gc_cnt -
          *    @c->lst.taken_empty_lebs
          *
-         * @empty_lebs are available because they are empty. @freeable_cnt are
-         * available because they contain only free and dirty space and the
-         * index allocation always occurs after wbufs are synch'ed.
-         * @idx_gc_cnt are available because they are index LEBs that have been
-         * garbage collected (including trivial GC) and are awaiting the commit
-         * before they can be unmapped - note that the in-the-gaps method will
-         * grab these if it needs them. @taken_empty_lebs are empty_lebs that
-         * have already been allocated for some purpose (also includes those
-         * LEBs on the @idx_gc list).
+         * @c->lst.empty_lebs are available because they are empty.
+         * @c->freeable_cnt are available because they contain only free and
+         * dirty space, @c->idx_gc_cnt are available because they are index
+         * LEBs that have been garbage collected and are awaiting the commit
+         * before they can be used. And the in-the-gaps method will grab these
+         * if it needs them. @c->lst.taken_empty_lebs are empty LEBs that have
+         * already been allocated for some purpose.
          *
-         * Note, @taken_empty_lebs may temporarily be higher by one because of
-         * the way we serialize LEB allocations and budgeting. See a comment in
-         * 'ubifs_find_free_space()'.
+         * Note, @c->idx_gc_cnt is included to both @c->lst.empty_lebs (because
+         * these LEBs are empty) and to @c->lst.taken_empty_lebs (because they
+         * are taken until after the commit).
+         *
+         * Note, @c->lst.taken_empty_lebs may temporarily be higher by one
+         * because of the way we serialize LEB allocations and budgeting. See a
+         * comment in 'ubifs_find_free_space()'.
          */
         lebs = c->lst.empty_lebs + c->freeable_cnt + c->idx_gc_cnt -
                c->lst.taken_empty_lebs;
diff --git a/fs/ubifs/compress.c b/fs/ubifs/compress.c
index 5bb51dac3c16..a0ada596b17c 100644
--- a/fs/ubifs/compress.c
+++ b/fs/ubifs/compress.c
@@ -91,8 +91,6 @@ struct ubifs_compressor *ubifs_compressors[UBIFS_COMPR_TYPES_CNT];
  *
  * Note, if the input buffer was not compressed, it is copied to the output
  * buffer and %UBIFS_COMPR_NONE is returned in @compr_type.
- *
- * This functions returns %0 on success or a negative error code on failure.
  */
 void ubifs_compress(const void *in_buf, int in_len, void *out_buf, int *out_len,
                     int *compr_type)
diff --git a/fs/ubifs/debug.c b/fs/ubifs/debug.c
index d7f7645779f2..7186400750e7 100644
--- a/fs/ubifs/debug.c
+++ b/fs/ubifs/debug.c
@@ -222,30 +222,38 @@ void dbg_dump_inode(const struct ubifs_info *c, const struct inode *inode)
 {
         const struct ubifs_inode *ui = ubifs_inode(inode);
 
-        printk(KERN_DEBUG "inode      %lu\n", inode->i_ino);
-        printk(KERN_DEBUG "size       %llu\n",
+        printk(KERN_DEBUG "Dump in-memory inode:");
+        printk(KERN_DEBUG "\tinode          %lu\n", inode->i_ino);
+        printk(KERN_DEBUG "\tsize           %llu\n",
                (unsigned long long)i_size_read(inode));
-        printk(KERN_DEBUG "nlink      %u\n", inode->i_nlink);
-        printk(KERN_DEBUG "uid        %u\n", (unsigned int)inode->i_uid);
-        printk(KERN_DEBUG "gid        %u\n", (unsigned int)inode->i_gid);
-        printk(KERN_DEBUG "atime      %u.%u\n",
+        printk(KERN_DEBUG "\tnlink          %u\n", inode->i_nlink);
+        printk(KERN_DEBUG "\tuid            %u\n", (unsigned int)inode->i_uid);
+        printk(KERN_DEBUG "\tgid            %u\n", (unsigned int)inode->i_gid);
+        printk(KERN_DEBUG "\tatime          %u.%u\n",
                (unsigned int)inode->i_atime.tv_sec,
                (unsigned int)inode->i_atime.tv_nsec);
-        printk(KERN_DEBUG "mtime      %u.%u\n",
+        printk(KERN_DEBUG "\tmtime          %u.%u\n",
                (unsigned int)inode->i_mtime.tv_sec,
                (unsigned int)inode->i_mtime.tv_nsec);
-        printk(KERN_DEBUG "ctime       %u.%u\n",
+        printk(KERN_DEBUG "\tctime          %u.%u\n",
                (unsigned int)inode->i_ctime.tv_sec,
                (unsigned int)inode->i_ctime.tv_nsec);
-        printk(KERN_DEBUG "creat_sqnum %llu\n", ui->creat_sqnum);
-        printk(KERN_DEBUG "xattr_size  %u\n", ui->xattr_size);
-        printk(KERN_DEBUG "xattr_cnt   %u\n", ui->xattr_cnt);
-        printk(KERN_DEBUG "xattr_names %u\n", ui->xattr_names);
-        printk(KERN_DEBUG "dirty       %u\n", ui->dirty);
-        printk(KERN_DEBUG "xattr       %u\n", ui->xattr);
-        printk(KERN_DEBUG "flags       %d\n", ui->flags);
-        printk(KERN_DEBUG "compr_type  %d\n", ui->compr_type);
-        printk(KERN_DEBUG "data_len    %d\n", ui->data_len);
+        printk(KERN_DEBUG "\tcreat_sqnum    %llu\n", ui->creat_sqnum);
+        printk(KERN_DEBUG "\txattr_size     %u\n", ui->xattr_size);
+        printk(KERN_DEBUG "\txattr_cnt      %u\n", ui->xattr_cnt);
+        printk(KERN_DEBUG "\txattr_names    %u\n", ui->xattr_names);
+        printk(KERN_DEBUG "\tdirty          %u\n", ui->dirty);
+        printk(KERN_DEBUG "\txattr          %u\n", ui->xattr);
+        printk(KERN_DEBUG "\tbulk_read      %u\n", ui->xattr);
+        printk(KERN_DEBUG "\tsynced_i_size  %llu\n",
+               (unsigned long long)ui->synced_i_size);
+        printk(KERN_DEBUG "\tui_size        %llu\n",
+               (unsigned long long)ui->ui_size);
+        printk(KERN_DEBUG "\tflags          %d\n", ui->flags);
+        printk(KERN_DEBUG "\tcompr_type     %d\n", ui->compr_type);
+        printk(KERN_DEBUG "\tlast_page_read %lu\n", ui->last_page_read);
+        printk(KERN_DEBUG "\tread_in_a_row  %lu\n", ui->read_in_a_row);
+        printk(KERN_DEBUG "\tdata_len       %d\n", ui->data_len);
 }
 
 void dbg_dump_node(const struct ubifs_info *c, const void *node)
@@ -647,6 +655,43 @@ void dbg_dump_lprops(struct ubifs_info *c)
         }
 }
 
+void dbg_dump_lpt_info(struct ubifs_info *c)
+{
+        int i;
+
+        spin_lock(&dbg_lock);
+        printk(KERN_DEBUG "\tlpt_sz:        %lld\n", c->lpt_sz);
+        printk(KERN_DEBUG "\tpnode_sz:      %d\n", c->pnode_sz);
+        printk(KERN_DEBUG "\tnnode_sz:      %d\n", c->nnode_sz);
+        printk(KERN_DEBUG "\tltab_sz:       %d\n", c->ltab_sz);
+        printk(KERN_DEBUG "\tlsave_sz:      %d\n", c->lsave_sz);
+        printk(KERN_DEBUG "\tbig_lpt:       %d\n", c->big_lpt);
+        printk(KERN_DEBUG "\tlpt_hght:      %d\n", c->lpt_hght);
+        printk(KERN_DEBUG "\tpnode_cnt:     %d\n", c->pnode_cnt);
+        printk(KERN_DEBUG "\tnnode_cnt:     %d\n", c->nnode_cnt);
+        printk(KERN_DEBUG "\tdirty_pn_cnt:  %d\n", c->dirty_pn_cnt);
+        printk(KERN_DEBUG "\tdirty_nn_cnt:  %d\n", c->dirty_nn_cnt);
+        printk(KERN_DEBUG "\tlsave_cnt:     %d\n", c->lsave_cnt);
+        printk(KERN_DEBUG "\tspace_bits:    %d\n", c->space_bits);
+        printk(KERN_DEBUG "\tlpt_lnum_bits: %d\n", c->lpt_lnum_bits);
+        printk(KERN_DEBUG "\tlpt_offs_bits: %d\n", c->lpt_offs_bits);
+        printk(KERN_DEBUG "\tlpt_spc_bits:  %d\n", c->lpt_spc_bits);
+        printk(KERN_DEBUG "\tpcnt_bits:     %d\n", c->pcnt_bits);
+        printk(KERN_DEBUG "\tlnum_bits:     %d\n", c->lnum_bits);
+        printk(KERN_DEBUG "\tLPT root is at %d:%d\n", c->lpt_lnum, c->lpt_offs);
+        printk(KERN_DEBUG "\tLPT head is at %d:%d\n",
+               c->nhead_lnum, c->nhead_offs);
+        printk(KERN_DEBUG "\tLPT ltab is at %d:%d\n", c->ltab_lnum, c->ltab_offs);
+        if (c->big_lpt)
+                printk(KERN_DEBUG "\tLPT lsave is at %d:%d\n",
+                       c->lsave_lnum, c->lsave_offs);
+        for (i = 0; i < c->lpt_lebs; i++)
+                printk(KERN_DEBUG "\tLPT LEB %d free %d dirty %d tgc %d "
+                       "cmt %d\n", i + c->lpt_first, c->ltab[i].free,
+                       c->ltab[i].dirty, c->ltab[i].tgc, c->ltab[i].cmt);
+        spin_unlock(&dbg_lock);
+}
+
 void dbg_dump_leb(const struct ubifs_info *c, int lnum)
 {
         struct ubifs_scan_leb *sleb;
diff --git a/fs/ubifs/debug.h b/fs/ubifs/debug.h
index 50315fc57185..33d6b95071e4 100644
--- a/fs/ubifs/debug.h
+++ b/fs/ubifs/debug.h
@@ -224,6 +224,7 @@ void dbg_dump_lstats(const struct ubifs_lp_stats *lst);
 void dbg_dump_budg(struct ubifs_info *c);
 void dbg_dump_lprop(const struct ubifs_info *c, const struct ubifs_lprops *lp);
 void dbg_dump_lprops(struct ubifs_info *c);
+void dbg_dump_lpt_info(struct ubifs_info *c);
 void dbg_dump_leb(const struct ubifs_info *c, int lnum);
 void dbg_dump_znode(const struct ubifs_info *c,
                     const struct ubifs_znode *znode);
@@ -249,6 +250,8 @@ int dbg_old_index_check_init(struct ubifs_info *c, struct ubifs_zbranch *zroot);
 int dbg_check_old_index(struct ubifs_info *c, struct ubifs_zbranch *zroot);
 int dbg_check_cats(struct ubifs_info *c);
 int dbg_check_ltab(struct ubifs_info *c);
+int dbg_chk_lpt_free_spc(struct ubifs_info *c);
+int dbg_chk_lpt_sz(struct ubifs_info *c, int action, int len);
 int dbg_check_synced_i_size(struct inode *inode);
 int dbg_check_dir_size(struct ubifs_info *c, const struct inode *dir);
 int dbg_check_tnc(struct ubifs_info *c, int extra);
@@ -367,6 +370,7 @@ static inline int dbg_change(struct ubi_volume_desc *desc, int lnum,
 #define dbg_dump_budg(c)                      ({})
 #define dbg_dump_lprop(c, lp)                 ({})
 #define dbg_dump_lprops(c)                    ({})
+#define dbg_dump_lpt_info(c)                  ({})
 #define dbg_dump_leb(c, lnum)                 ({})
 #define dbg_dump_znode(c, znode)              ({})
 #define dbg_dump_heap(c, heap, cat)           ({})
@@ -379,6 +383,8 @@ static inline int dbg_change(struct ubi_volume_desc *desc, int lnum,
 #define dbg_check_old_index(c, zroot)              0
 #define dbg_check_cats(c)                          0
 #define dbg_check_ltab(c)                          0
+#define dbg_chk_lpt_free_spc(c)                    0
+#define dbg_chk_lpt_sz(c, action, len)             0
 #define dbg_check_synced_i_size(inode)             0
 #define dbg_check_dir_size(c, dir)                 0
 #define dbg_check_tnc(c, x)                        0
diff --git a/fs/ubifs/file.c b/fs/ubifs/file.c
index 3d698e2022b1..51cf511d44d9 100644
--- a/fs/ubifs/file.c
+++ b/fs/ubifs/file.c
@@ -147,6 +147,12 @@ static int do_readpage(struct page *page)
                                 err = ret;
                                 if (err != -ENOENT)
                                         break;
+                        } else if (block + 1 == beyond) {
+                                int dlen = le32_to_cpu(dn->size);
+                                int ilen = i_size & (UBIFS_BLOCK_SIZE - 1);
+
+                                if (ilen && ilen < dlen)
+                                        memset(addr + ilen, 0, dlen - ilen);
                         }
                 }
                 if (++i >= UBIFS_BLOCKS_PER_PAGE)
@@ -577,8 +583,262 @@ out:
         return copied;
 }
 
+/**
+ * populate_page - copy data nodes into a page for bulk-read.
+ * @c: UBIFS file-system description object
+ * @page: page
+ * @bu: bulk-read information
+ * @n: next zbranch slot
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+static int populate_page(struct ubifs_info *c, struct page *page,
+                         struct bu_info *bu, int *n)
+{
+        int i = 0, nn = *n, offs = bu->zbranch[0].offs, hole = 0, read = 0;
+        struct inode *inode = page->mapping->host;
+        loff_t i_size = i_size_read(inode);
+        unsigned int page_block;
+        void *addr, *zaddr;
+        pgoff_t end_index;
+
+        dbg_gen("ino %lu, pg %lu, i_size %lld, flags %#lx",
+                inode->i_ino, page->index, i_size, page->flags);
+
+        addr = zaddr = kmap(page);
+
+        end_index = (i_size - 1) >> PAGE_CACHE_SHIFT;
+        if (!i_size || page->index > end_index) {
+                hole = 1;
+                memset(addr, 0, PAGE_CACHE_SIZE);
+                goto out_hole;
+        }
+
+        page_block = page->index << UBIFS_BLOCKS_PER_PAGE_SHIFT;
+        while (1) {
+                int err, len, out_len, dlen;
+
+                if (nn >= bu->cnt) {
+                        hole = 1;
+                        memset(addr, 0, UBIFS_BLOCK_SIZE);
+                } else if (key_block(c, &bu->zbranch[nn].key) == page_block) {
+                        struct ubifs_data_node *dn;
+
+                        dn = bu->buf + (bu->zbranch[nn].offs - offs);
+
+                        ubifs_assert(dn->ch.sqnum >
+                                     ubifs_inode(inode)->creat_sqnum);
+
+                        len = le32_to_cpu(dn->size);
+                        if (len <= 0 || len > UBIFS_BLOCK_SIZE)
+                                goto out_err;
+
+                        dlen = le32_to_cpu(dn->ch.len) - UBIFS_DATA_NODE_SZ;
+                        out_len = UBIFS_BLOCK_SIZE;
+                        err = ubifs_decompress(&dn->data, dlen, addr, &out_len,
+                                               le16_to_cpu(dn->compr_type));
+                        if (err || len != out_len)
+                                goto out_err;
+
+                        if (len < UBIFS_BLOCK_SIZE)
+                                memset(addr + len, 0, UBIFS_BLOCK_SIZE - len);
+
+                        nn += 1;
+                        read = (i << UBIFS_BLOCK_SHIFT) + len;
+                } else if (key_block(c, &bu->zbranch[nn].key) < page_block) {
+                        nn += 1;
+                        continue;
+                } else {
+                        hole = 1;
+                        memset(addr, 0, UBIFS_BLOCK_SIZE);
+                }
+                if (++i >= UBIFS_BLOCKS_PER_PAGE)
+                        break;
+                addr += UBIFS_BLOCK_SIZE;
+                page_block += 1;
+        }
+
+        if (end_index == page->index) {
+                int len = i_size & (PAGE_CACHE_SIZE - 1);
+
+                if (len && len < read)
+                        memset(zaddr + len, 0, read - len);
+        }
+
+out_hole:
+        if (hole) {
+                SetPageChecked(page);
+                dbg_gen("hole");
+        }
+
+        SetPageUptodate(page);
+        ClearPageError(page);
+        flush_dcache_page(page);
+        kunmap(page);
+        *n = nn;
+        return 0;
+
+out_err:
+        ClearPageUptodate(page);
+        SetPageError(page);
+        flush_dcache_page(page);
+        kunmap(page);
+        ubifs_err("bad data node (block %u, inode %lu)",
+                  page_block, inode->i_ino);
+        return -EINVAL;
+}
+
+/**
+ * ubifs_do_bulk_read - do bulk-read.
+ * @c: UBIFS file-system description object
+ * @page1: first page
+ *
+ * This function returns %1 if the bulk-read is done, otherwise %0 is returned.
+ */
+static int ubifs_do_bulk_read(struct ubifs_info *c, struct page *page1)
+{
+        pgoff_t offset = page1->index, end_index;
+        struct address_space *mapping = page1->mapping;
+        struct inode *inode = mapping->host;
+        struct ubifs_inode *ui = ubifs_inode(inode);
+        struct bu_info *bu;
+        int err, page_idx, page_cnt, ret = 0, n = 0;
+        loff_t isize;
+
+        bu = kmalloc(sizeof(struct bu_info), GFP_NOFS);
+        if (!bu)
+                return 0;
+
+        bu->buf_len = c->bulk_read_buf_size;
+        bu->buf = kmalloc(bu->buf_len, GFP_NOFS);
+        if (!bu->buf)
+                goto out_free;
+
+        data_key_init(c, &bu->key, inode->i_ino,
+                      offset << UBIFS_BLOCKS_PER_PAGE_SHIFT);
+
+        err = ubifs_tnc_get_bu_keys(c, bu);
+        if (err)
+                goto out_warn;
+
+        if (bu->eof) {
+                /* Turn off bulk-read at the end of the file */
+                ui->read_in_a_row = 1;
+                ui->bulk_read = 0;
+        }
+
+        page_cnt = bu->blk_cnt >> UBIFS_BLOCKS_PER_PAGE_SHIFT;
+        if (!page_cnt) {
+                /*
+                 * This happens when there are multiple blocks per page and the
+                 * blocks for the first page we are looking for, are not
+                 * together. If all the pages were like this, bulk-read would
+                 * reduce performance, so we turn it off for a while.
+                 */
+                ui->read_in_a_row = 0;
+                ui->bulk_read = 0;
+                goto out_free;
+        }
+
+        if (bu->cnt) {
+                err = ubifs_tnc_bulk_read(c, bu);
+                if (err)
+                        goto out_warn;
+        }
+
+        err = populate_page(c, page1, bu, &n);
+        if (err)
+                goto out_warn;
+
+        unlock_page(page1);
+        ret = 1;
+
+        isize = i_size_read(inode);
+        if (isize == 0)
+                goto out_free;
+        end_index = ((isize - 1) >> PAGE_CACHE_SHIFT);
+
+        for (page_idx = 1; page_idx < page_cnt; page_idx++) {
+                pgoff_t page_offset = offset + page_idx;
+                struct page *page;
+
+                if (page_offset > end_index)
+                        break;
+                page = find_or_create_page(mapping, page_offset,
+                                           GFP_NOFS | __GFP_COLD);
+                if (!page)
+                        break;
+                if (!PageUptodate(page))
+                        err = populate_page(c, page, bu, &n);
+                unlock_page(page);
+                page_cache_release(page);
+                if (err)
+                        break;
+        }
+
+        ui->last_page_read = offset + page_idx - 1;
+
+out_free:
+        kfree(bu->buf);
+        kfree(bu);
+        return ret;
+
+out_warn:
+        ubifs_warn("ignoring error %d and skipping bulk-read", err);
+        goto out_free;
+}
+
+/**
+ * ubifs_bulk_read - determine whether to bulk-read and, if so, do it.
+ * @page: page from which to start bulk-read.
+ *
+ * Some flash media are capable of reading sequentially at faster rates. UBIFS
+ * bulk-read facility is designed to take advantage of that, by reading in one
+ * go consecutive data nodes that are also located consecutively in the same
+ * LEB. This function returns %1 if a bulk-read is done and %0 otherwise.
+ */
+static int ubifs_bulk_read(struct page *page)
+{
+        struct inode *inode = page->mapping->host;
+        struct ubifs_info *c = inode->i_sb->s_fs_info;
+        struct ubifs_inode *ui = ubifs_inode(inode);
+        pgoff_t index = page->index, last_page_read = ui->last_page_read;
+        int ret = 0;
+
+        ui->last_page_read = index;
+
+        if (!c->bulk_read)
+                return 0;
+        /*
+         * Bulk-read is protected by ui_mutex, but it is an optimization, so
+         * don't bother if we cannot lock the mutex.
+         */
+        if (!mutex_trylock(&ui->ui_mutex))
+                return 0;
+        if (index != last_page_read + 1) {
+                /* Turn off bulk-read if we stop reading sequentially */
+                ui->read_in_a_row = 1;
+                if (ui->bulk_read)
+                        ui->bulk_read = 0;
+                goto out_unlock;
+        }
+        if (!ui->bulk_read) {
+                ui->read_in_a_row += 1;
+                if (ui->read_in_a_row < 3)
+                        goto out_unlock;
+                /* Three reads in a row, so switch on bulk-read */
+                ui->bulk_read = 1;
+        }
+        ret = ubifs_do_bulk_read(c, page);
+out_unlock:
+        mutex_unlock(&ui->ui_mutex);
+        return ret;
+}
+
 static int ubifs_readpage(struct file *file, struct page *page)
 {
+        if (ubifs_bulk_read(page))
+                return 0;
         do_readpage(page);
         unlock_page(page);
         return 0;
diff --git a/fs/ubifs/find.c b/fs/ubifs/find.c
index 47814cde2407..717d79c97c5e 100644
--- a/fs/ubifs/find.c
+++ b/fs/ubifs/find.c
@@ -901,11 +901,11 @@ static int get_idx_gc_leb(struct ubifs_info *c)
          * it is needed now for this commit.
          */
         lp = ubifs_lpt_lookup_dirty(c, lnum);
-        if (unlikely(IS_ERR(lp)))
+        if (IS_ERR(lp))
                 return PTR_ERR(lp);
         lp = ubifs_change_lp(c, lp, LPROPS_NC, LPROPS_NC,
                              lp->flags | LPROPS_INDEX, -1);
-        if (unlikely(IS_ERR(lp)))
+        if (IS_ERR(lp))
                 return PTR_ERR(lp);
         dbg_find("LEB %d, dirty %d and free %d flags %#x",
                  lp->lnum, lp->dirty, lp->free, lp->flags);
diff --git a/fs/ubifs/gc.c b/fs/ubifs/gc.c
index 02aba36fe3d4..0bef6501d58a 100644
--- a/fs/ubifs/gc.c
+++ b/fs/ubifs/gc.c
@@ -96,6 +96,48 @@ static int switch_gc_head(struct ubifs_info *c)
 }
 
 /**
+ * joinup - bring data nodes for an inode together.
+ * @c: UBIFS file-system description object
+ * @sleb: describes scanned LEB
+ * @inum: inode number
+ * @blk: block number
+ * @data: list to which to add data nodes
+ *
+ * This function looks at the first few nodes in the scanned LEB @sleb and adds
+ * them to @data if they are data nodes from @inum and have a larger block
+ * number than @blk. This function returns %0 on success and a negative error
+ * code on failure.
+ */
+static int joinup(struct ubifs_info *c, struct ubifs_scan_leb *sleb, ino_t inum,
+                  unsigned int blk, struct list_head *data)
+{
+        int err, cnt = 6, lnum = sleb->lnum, offs;
+        struct ubifs_scan_node *snod, *tmp;
+        union ubifs_key *key;
+
+        list_for_each_entry_safe(snod, tmp, &sleb->nodes, list) {
+                key = &snod->key;
+                if (key_inum(c, key) == inum &&
+                    key_type(c, key) == UBIFS_DATA_KEY &&
+                    key_block(c, key) > blk) {
+                        offs = snod->offs;
+                        err = ubifs_tnc_has_node(c, key, 0, lnum, offs, 0);
+                        if (err < 0)
+                                return err;
+                        list_del(&snod->list);
+                        if (err) {
+                                list_add_tail(&snod->list, data);
+                                blk = key_block(c, key);
+                        } else
+                                kfree(snod);
+                        cnt = 6;
+                } else if (--cnt == 0)
+                        break;
+        }
+        return 0;
+}
+
+/**
  * move_nodes - move nodes.
  * @c: UBIFS file-system description object
  * @sleb: describes nodes to move
@@ -116,16 +158,21 @@ static int switch_gc_head(struct ubifs_info *c)
 static int move_nodes(struct ubifs_info *c, struct ubifs_scan_leb *sleb)
 {
         struct ubifs_scan_node *snod, *tmp;
-        struct list_head large, medium, small;
+        struct list_head data, large, medium, small;
         struct ubifs_wbuf *wbuf = &c->jheads[GCHD].wbuf;
         int avail, err, min = INT_MAX;
+        unsigned int blk = 0;
+        ino_t inum = 0;
 
+        INIT_LIST_HEAD(&data);
         INIT_LIST_HEAD(&large);
         INIT_LIST_HEAD(&medium);
         INIT_LIST_HEAD(&small);
 
-        list_for_each_entry_safe(snod, tmp, &sleb->nodes, list) {
-                struct list_head *lst;
+        while (!list_empty(&sleb->nodes)) {
+                struct list_head *lst = sleb->nodes.next;
+
+                snod = list_entry(lst, struct ubifs_scan_node, list);
 
                 ubifs_assert(snod->type != UBIFS_IDX_NODE);
                 ubifs_assert(snod->type != UBIFS_REF_NODE);
@@ -136,7 +183,6 @@ static int move_nodes(struct ubifs_info *c, struct ubifs_scan_leb *sleb)
                 if (err < 0)
                         goto out;
 
-                lst = &snod->list;
                 list_del(lst);
                 if (!err) {
                         /* The node is obsolete, remove it from the list */
@@ -145,15 +191,30 @@ static int move_nodes(struct ubifs_info *c, struct ubifs_scan_leb *sleb)
                 }
 
                 /*
-                 * Sort the list of nodes so that large nodes go first, and
-                 * small nodes go last.
+                 * Sort the list of nodes so that data nodes go first, large
+                 * nodes go second, and small nodes go last.
                  */
-                if (snod->len > MEDIUM_NODE_WM)
-                        list_add(lst, &large);
+                if (key_type(c, &snod->key) == UBIFS_DATA_KEY) {
+                        if (inum != key_inum(c, &snod->key)) {
+                                if (inum) {
+                                        /*
+                                         * Try to move data nodes from the same
+                                         * inode together.
+                                         */
+                                        err = joinup(c, sleb, inum, blk, &data);
+                                        if (err)
+                                                goto out;
+                                }
+                                inum = key_inum(c, &snod->key);
+                                blk = key_block(c, &snod->key);
+                        }
+                        list_add_tail(lst, &data);
+                } else if (snod->len > MEDIUM_NODE_WM)
+                        list_add_tail(lst, &large);
                 else if (snod->len > SMALL_NODE_WM)
-                        list_add(lst, &medium);
+                        list_add_tail(lst, &medium);
                 else
-                        list_add(lst, &small);
+                        list_add_tail(lst, &small);
 
                 /* And find the smallest node */
                 if (snod->len < min)
@@ -164,6 +225,7 @@ static int move_nodes(struct ubifs_info *c, struct ubifs_scan_leb *sleb)
          * Join the tree lists so that we'd have one roughly sorted list
          * ('large' will be the head of the joined list).
          */
+        list_splice(&data, &large);
         list_splice(&medium, large.prev);
         list_splice(&small, large.prev);
 
@@ -653,7 +715,7 @@ int ubifs_gc_start_commit(struct ubifs_info *c)
          */
         while (1) {
                 lp = ubifs_fast_find_freeable(c);
-                if (unlikely(IS_ERR(lp))) {
+                if (IS_ERR(lp)) {
                         err = PTR_ERR(lp);
                         goto out;
                 }
@@ -665,7 +727,7 @@ int ubifs_gc_start_commit(struct ubifs_info *c)
                 if (err)
                         goto out;
                 lp = ubifs_change_lp(c, lp, c->leb_size, 0, lp->flags, 0);
-                if (unlikely(IS_ERR(lp))) {
+                if (IS_ERR(lp)) {
                         err = PTR_ERR(lp);
                         goto out;
                 }
@@ -680,7 +742,7 @@ int ubifs_gc_start_commit(struct ubifs_info *c)
         /* Record index freeable LEBs for unmapping after commit */
         while (1) {
                 lp = ubifs_fast_find_frdi_idx(c);
-                if (unlikely(IS_ERR(lp))) {
+                if (IS_ERR(lp)) {
                         err = PTR_ERR(lp);
                         goto out;
                 }
@@ -696,7 +758,7 @@ int ubifs_gc_start_commit(struct ubifs_info *c)
                 /* Don't release the LEB until after the next commit */
                 flags = (lp->flags | LPROPS_TAKEN) ^ LPROPS_INDEX;
                 lp = ubifs_change_lp(c, lp, c->leb_size, 0, flags, 1);
-                if (unlikely(IS_ERR(lp))) {
+                if (IS_ERR(lp)) {
                         err = PTR_ERR(lp);
                         kfree(idx_gc);
                         goto out;
diff --git a/fs/ubifs/io.c b/fs/ubifs/io.c
index 054363f2b207..01682713af69 100644
--- a/fs/ubifs/io.c
+++ b/fs/ubifs/io.c
@@ -62,6 +62,7 @@ void ubifs_ro_mode(struct ubifs_info *c, int err)
 {
         if (!c->ro_media) {
                 c->ro_media = 1;
+                c->no_chk_data_crc = 0;
                 ubifs_warn("switched to read-only mode, error %d", err);
                 dbg_dump_stack();
         }
@@ -74,6 +75,7 @@ void ubifs_ro_mode(struct ubifs_info *c, int err)
  * @lnum: logical eraseblock number
  * @offs: offset within the logical eraseblock
  * @quiet: print no messages
+ * @chk_crc: indicates whether to always check the CRC
  *
  * This function checks node magic number and CRC checksum. This function also
  * validates node length to prevent UBIFS from becoming crazy when an attacker
@@ -85,7 +87,7 @@ void ubifs_ro_mode(struct ubifs_info *c, int err)
  * or magic.
  */
 int ubifs_check_node(const struct ubifs_info *c, const void *buf, int lnum,
-                     int offs, int quiet)
+                     int offs, int quiet, int chk_crc)
 {
         int err = -EINVAL, type, node_len;
         uint32_t crc, node_crc, magic;
@@ -121,6 +123,10 @@ int ubifs_check_node(const struct ubifs_info *c, const void *buf, int lnum,
                    node_len > c->ranges[type].max_len)
                 goto out_len;
 
+        if (!chk_crc && type == UBIFS_DATA_NODE && !c->always_chk_crc)
+                if (c->no_chk_data_crc)
+                        return 0;
+
         crc = crc32(UBIFS_CRC32_INIT, buf + 8, node_len - 8);
         node_crc = le32_to_cpu(ch->crc);
         if (crc != node_crc) {
@@ -722,7 +728,7 @@ int ubifs_read_node_wbuf(struct ubifs_wbuf *wbuf, void *buf, int type, int len,
                 goto out;
         }
 
-        err = ubifs_check_node(c, buf, lnum, offs, 0);
+        err = ubifs_check_node(c, buf, lnum, offs, 0, 0);
         if (err) {
                 ubifs_err("expected node type %d", type);
                 return err;
@@ -781,7 +787,7 @@ int ubifs_read_node(const struct ubifs_info *c, void *buf, int type, int len,
                 goto out;
         }
 
-        err = ubifs_check_node(c, buf, lnum, offs, 0);
+        err = ubifs_check_node(c, buf, lnum, offs, 0, 0);
         if (err) {
                 ubifs_err("expected node type %d", type);
                 return err;
diff --git a/fs/ubifs/key.h b/fs/ubifs/key.h
index 8f7476007549..9ee65086f627 100644
--- a/fs/ubifs/key.h
+++ b/fs/ubifs/key.h
@@ -484,7 +484,7 @@ static inline void key_copy(const struct ubifs_info *c,
  * @key2: the second key to compare
  *
  * This function compares 2 keys and returns %-1 if @key1 is less than
- * @key2, 0 if the keys are equivalent and %1 if @key1 is greater than @key2.
+ * @key2, %0 if the keys are equivalent and %1 if @key1 is greater than @key2.
  */
 static inline int keys_cmp(const struct ubifs_info *c,
                            const union ubifs_key *key1,
@@ -503,6 +503,26 @@ static inline int keys_cmp(const struct ubifs_info *c,
 }
 
 /**
+ * keys_eq - determine if keys are equivalent.
+ * @c: UBIFS file-system description object
+ * @key1: the first key to compare
+ * @key2: the second key to compare
+ *
+ * This function compares 2 keys and returns %1 if @key1 is equal to @key2 and
+ * %0 if not.
+ */
+static inline int keys_eq(const struct ubifs_info *c,
+                          const union ubifs_key *key1,
+                          const union ubifs_key *key2)
+{
+        if (key1->u32[0] != key2->u32[0])
+                return 0;
+        if (key1->u32[1] != key2->u32[1])
+                return 0;
+        return 1;
+}
+
+/**
  * is_hash_key - is a key vulnerable to hash collisions.
  * @c: UBIFS file-system description object
  * @key: key
diff --git a/fs/ubifs/lprops.c b/fs/ubifs/lprops.c
index 2ba93da71b65..f27176e9b70d 100644
--- a/fs/ubifs/lprops.c
+++ b/fs/ubifs/lprops.c
@@ -125,6 +125,7 @@ static void adjust_lpt_heap(struct ubifs_info *c, struct ubifs_lpt_heap *heap,
                         }
                 }
         }
+
         /* Not greater than parent, so compare to children */
         while (1) {
                 /* Compare to left child */
@@ -460,18 +461,6 @@ static void change_category(struct ubifs_info *c, struct ubifs_lprops *lprops)
 }
 
 /**
- * ubifs_get_lprops - get reference to LEB properties.
- * @c: the UBIFS file-system description object
- *
- * This function locks lprops. Lprops have to be unlocked by
- * 'ubifs_release_lprops()'.
- */
-void ubifs_get_lprops(struct ubifs_info *c)
-{
-        mutex_lock(&c->lp_mutex);
-}
-
-/**
  * calc_dark - calculate LEB dark space size.
  * @c: the UBIFS file-system description object
  * @spc: amount of free and dirty space in the LEB
@@ -576,7 +565,6 @@ const struct ubifs_lprops *ubifs_change_lp(struct ubifs_info *c,
         ubifs_assert(!(lprops->free & 7) && !(lprops->dirty & 7));
 
         spin_lock(&c->space_lock);
-
         if ((lprops->flags & LPROPS_TAKEN) && lprops->free == c->leb_size)
                 c->lst.taken_empty_lebs -= 1;
 
@@ -637,31 +625,12 @@ const struct ubifs_lprops *ubifs_change_lp(struct ubifs_info *c,
                 c->lst.taken_empty_lebs += 1;
 
         change_category(c, lprops);
-
         c->idx_gc_cnt += idx_gc_cnt;
-
         spin_unlock(&c->space_lock);
-
         return lprops;
 }
 
 /**
- * ubifs_release_lprops - release lprops lock.
- * @c: the UBIFS file-system description object
- *
- * This function has to be called after each 'ubifs_get_lprops()' call to
- * unlock lprops.
- */
-void ubifs_release_lprops(struct ubifs_info *c)
-{
-        ubifs_assert(mutex_is_locked(&c->lp_mutex));
-        ubifs_assert(c->lst.empty_lebs >= 0 &&
-                     c->lst.empty_lebs <= c->main_lebs);
-
-        mutex_unlock(&c->lp_mutex);
-}
-
-/**
  * ubifs_get_lp_stats - get lprops statistics.
  * @c: UBIFS file-system description object
  * @st: return statistics
@@ -1262,7 +1231,6 @@ static int scan_check_cb(struct ubifs_info *c,
         }
 
         ubifs_scan_destroy(sleb);
-
         return LPT_SCAN_CONTINUE;
 
 out_print:
diff --git a/fs/ubifs/lpt.c b/fs/ubifs/lpt.c
index 9ff2463177e5..db8bd0e518b2 100644
--- a/fs/ubifs/lpt.c
+++ b/fs/ubifs/lpt.c
@@ -109,7 +109,8 @@ static void do_calc_lpt_geom(struct ubifs_info *c)
         c->lpt_sz = (long long)c->pnode_cnt * c->pnode_sz;
         c->lpt_sz += (long long)c->nnode_cnt * c->nnode_sz;
         c->lpt_sz += c->ltab_sz;
-        c->lpt_sz += c->lsave_sz;
+        if (c->big_lpt)
+                c->lpt_sz += c->lsave_sz;
 
         /* Add wastage */
         sz = c->lpt_sz;
@@ -287,25 +288,56 @@ uint32_t ubifs_unpack_bits(uint8_t **addr, int *pos, int nrbits)
         const int k = 32 - nrbits;
         uint8_t *p = *addr;
         int b = *pos;
-        uint32_t val;
+        uint32_t uninitialized_var(val);
+        const int bytes = (nrbits + b + 7) >> 3;
 
         ubifs_assert(nrbits > 0);
         ubifs_assert(nrbits <= 32);
         ubifs_assert(*pos >= 0);
         ubifs_assert(*pos < 8);
         if (b) {
-                val = p[1] | ((uint32_t)p[2] << 8) | ((uint32_t)p[3] << 16) |
-                      ((uint32_t)p[4] << 24);
+                switch (bytes) {
+                case 2:
+                        val = p[1];
+                        break;
+                case 3:
+                        val = p[1] | ((uint32_t)p[2] << 8);
+                        break;
+                case 4:
+                        val = p[1] | ((uint32_t)p[2] << 8) |
+                                     ((uint32_t)p[3] << 16);
+                        break;
+                case 5:
+                        val = p[1] | ((uint32_t)p[2] << 8) |
+                                     ((uint32_t)p[3] << 16) |
+                                     ((uint32_t)p[4] << 24);
+                }
                 val <<= (8 - b);
                 val |= *p >> b;
                 nrbits += b;
-        } else
-                val = p[0] | ((uint32_t)p[1] << 8) | ((uint32_t)p[2] << 16) |
-                      ((uint32_t)p[3] << 24);
+        } else {
+                switch (bytes) {
+                case 1:
+                        val = p[0];
+                        break;
+                case 2:
+                        val = p[0] | ((uint32_t)p[1] << 8);
+                        break;
+                case 3:
+                        val = p[0] | ((uint32_t)p[1] << 8) |
+                                     ((uint32_t)p[2] << 16);
+                        break;
+                case 4:
+                        val = p[0] | ((uint32_t)p[1] << 8) |
+                                     ((uint32_t)p[2] << 16) |
+                                     ((uint32_t)p[3] << 24);
+                        break;
+                }
+        }
         val <<= k;
         val >>= k;
         b = nrbits & 7;
-        p += nrbits / 8;
+        p += nrbits >> 3;
         *addr = p;
         *pos = b;
         ubifs_assert((val >> nrbits) == 0 || nrbits - b == 32);
diff --git a/fs/ubifs/lpt_commit.c b/fs/ubifs/lpt_commit.c
index 5f0b83e20af6..eed5a0025d63 100644
--- a/fs/ubifs/lpt_commit.c
+++ b/fs/ubifs/lpt_commit.c
@@ -177,8 +177,6 @@ static int alloc_lpt_leb(struct ubifs_info *c, int *lnum)
                         return 0;
                 }
         }
-        dbg_err("last LEB %d", *lnum);
-        dump_stack();
         return -ENOSPC;
 }
 
@@ -193,6 +191,9 @@ static int layout_cnodes(struct ubifs_info *c)
         int lnum, offs, len, alen, done_lsave, done_ltab, err;
         struct ubifs_cnode *cnode;
 
+        err = dbg_chk_lpt_sz(c, 0, 0);
+        if (err)
+                return err;
         cnode = c->lpt_cnext;
         if (!cnode)
                 return 0;
@@ -206,6 +207,7 @@ static int layout_cnodes(struct ubifs_info *c)
                 c->lsave_lnum = lnum;
                 c->lsave_offs = offs;
                 offs += c->lsave_sz;
+                dbg_chk_lpt_sz(c, 1, c->lsave_sz);
         }
 
         if (offs + c->ltab_sz <= c->leb_size) {
@@ -213,6 +215,7 @@ static int layout_cnodes(struct ubifs_info *c)
                 c->ltab_lnum = lnum;
                 c->ltab_offs = offs;
                 offs += c->ltab_sz;
+                dbg_chk_lpt_sz(c, 1, c->ltab_sz);
         }
 
         do {
@@ -226,9 +229,10 @@ static int layout_cnodes(struct ubifs_info *c)
                 while (offs + len > c->leb_size) {
                         alen = ALIGN(offs, c->min_io_size);
                         upd_ltab(c, lnum, c->leb_size - alen, alen - offs);
+                        dbg_chk_lpt_sz(c, 2, alen - offs);
                         err = alloc_lpt_leb(c, &lnum);
                         if (err)
-                                return err;
+                                goto no_space;
                         offs = 0;
                         ubifs_assert(lnum >= c->lpt_first &&
                                      lnum <= c->lpt_last);
@@ -238,6 +242,7 @@ static int layout_cnodes(struct ubifs_info *c)
                                 c->lsave_lnum = lnum;
                                 c->lsave_offs = offs;
                                 offs += c->lsave_sz;
+                                dbg_chk_lpt_sz(c, 1, c->lsave_sz);
                                 continue;
                         }
                         if (!done_ltab) {
@@ -245,6 +250,7 @@ static int layout_cnodes(struct ubifs_info *c)
                                 c->ltab_lnum = lnum;
                                 c->ltab_offs = offs;
                                 offs += c->ltab_sz;
+                                dbg_chk_lpt_sz(c, 1, c->ltab_sz);
                                 continue;
                         }
                         break;
@@ -257,6 +263,7 @@ static int layout_cnodes(struct ubifs_info *c)
                         c->lpt_offs = offs;
                 }
                 offs += len;
+                dbg_chk_lpt_sz(c, 1, len);
                 cnode = cnode->cnext;
         } while (cnode && cnode != c->lpt_cnext);
 
@@ -265,9 +272,10 @@ static int layout_cnodes(struct ubifs_info *c)
                 if (offs + c->lsave_sz > c->leb_size) {
                         alen = ALIGN(offs, c->min_io_size);
                         upd_ltab(c, lnum, c->leb_size - alen, alen - offs);
+                        dbg_chk_lpt_sz(c, 2, alen - offs);
                         err = alloc_lpt_leb(c, &lnum);
                         if (err)
-                                return err;
+                                goto no_space;
                         offs = 0;
                         ubifs_assert(lnum >= c->lpt_first &&
                                      lnum <= c->lpt_last);
@@ -276,6 +284,7 @@ static int layout_cnodes(struct ubifs_info *c)
                 c->lsave_lnum = lnum;
                 c->lsave_offs = offs;
                 offs += c->lsave_sz;
+                dbg_chk_lpt_sz(c, 1, c->lsave_sz);
         }
 
         /* Make sure to place LPT's own lprops table */
@@ -283,9 +292,10 @@ static int layout_cnodes(struct ubifs_info *c)
                 if (offs + c->ltab_sz > c->leb_size) {
                         alen = ALIGN(offs, c->min_io_size);
                         upd_ltab(c, lnum, c->leb_size - alen, alen - offs);
+                        dbg_chk_lpt_sz(c, 2, alen - offs);
                         err = alloc_lpt_leb(c, &lnum);
                         if (err)
-                                return err;
+                                goto no_space;
                         offs = 0;
                         ubifs_assert(lnum >= c->lpt_first &&
                                      lnum <= c->lpt_last);
@@ -294,11 +304,23 @@ static int layout_cnodes(struct ubifs_info *c)
                 c->ltab_lnum = lnum;
                 c->ltab_offs = offs;
                 offs += c->ltab_sz;
+                dbg_chk_lpt_sz(c, 1, c->ltab_sz);
         }
 
         alen = ALIGN(offs, c->min_io_size);
         upd_ltab(c, lnum, c->leb_size - alen, alen - offs);
+        dbg_chk_lpt_sz(c, 4, alen - offs);
+        err = dbg_chk_lpt_sz(c, 3, alen);
+        if (err)
+                return err;
         return 0;
+
+no_space:
+        ubifs_err("LPT out of space");
+        dbg_err("LPT out of space at LEB %d:%d needing %d, done_ltab %d, "
+                "done_lsave %d", lnum, offs, len, done_ltab, done_lsave);
+        dbg_dump_lpt_info(c);
+        return err;
 }
 
 /**
@@ -333,8 +355,6 @@ static int realloc_lpt_leb(struct ubifs_info *c, int *lnum)
                         *lnum = i + c->lpt_first;
                         return 0;
                 }
-        dbg_err("last LEB %d", *lnum);
-        dump_stack();
         return -ENOSPC;
 }
 
@@ -369,12 +389,14 @@ static int write_cnodes(struct ubifs_info *c)
                 done_lsave = 1;
                 ubifs_pack_lsave(c, buf + offs, c->lsave);
                 offs += c->lsave_sz;
+                dbg_chk_lpt_sz(c, 1, c->lsave_sz);
         }
 
         if (offs + c->ltab_sz <= c->leb_size) {
                 done_ltab = 1;
                 ubifs_pack_ltab(c, buf + offs, c->ltab_cmt);
                 offs += c->ltab_sz;
+                dbg_chk_lpt_sz(c, 1, c->ltab_sz);
         }
 
         /* Loop for each cnode */
@@ -392,10 +414,12 @@ static int write_cnodes(struct ubifs_info *c)
                                                        alen, UBI_SHORTTERM);
                                 if (err)
                                         return err;
+                                dbg_chk_lpt_sz(c, 4, alen - wlen);
                         }
+                        dbg_chk_lpt_sz(c, 2, 0);
                         err = realloc_lpt_leb(c, &lnum);
                         if (err)
-                                return err;
+                                goto no_space;
                         offs = 0;
                         from = 0;
                         ubifs_assert(lnum >= c->lpt_first &&
@@ -408,12 +432,14 @@ static int write_cnodes(struct ubifs_info *c)
                                 done_lsave = 1;
                                 ubifs_pack_lsave(c, buf + offs, c->lsave);
                                 offs += c->lsave_sz;
+                                dbg_chk_lpt_sz(c, 1, c->lsave_sz);
                                 continue;
                         }
                         if (!done_ltab) {
                                 done_ltab = 1;
                                 ubifs_pack_ltab(c, buf + offs, c->ltab_cmt);
                                 offs += c->ltab_sz;
+                                dbg_chk_lpt_sz(c, 1, c->ltab_sz);
                                 continue;
                         }
                         break;
@@ -435,6 +461,7 @@ static int write_cnodes(struct ubifs_info *c)
                 clear_bit(COW_ZNODE, &cnode->flags);
                 smp_mb__after_clear_bit();
                 offs += len;
+                dbg_chk_lpt_sz(c, 1, len);
                 cnode = cnode->cnext;
         } while (cnode && cnode != c->lpt_cnext);
 
@@ -448,9 +475,10 @@ static int write_cnodes(struct ubifs_info *c)
                                               UBI_SHORTTERM);
                         if (err)
                                 return err;
+                        dbg_chk_lpt_sz(c, 2, alen - wlen);
                         err = realloc_lpt_leb(c, &lnum);
                         if (err)
-                                return err;
+                                goto no_space;
                         offs = 0;
                         ubifs_assert(lnum >= c->lpt_first &&
                                      lnum <= c->lpt_last);
@@ -461,6 +489,7 @@ static int write_cnodes(struct ubifs_info *c)
                 done_lsave = 1;
                 ubifs_pack_lsave(c, buf + offs, c->lsave);
                 offs += c->lsave_sz;
+                dbg_chk_lpt_sz(c, 1, c->lsave_sz);
         }
 
         /* Make sure to place LPT's own lprops table */
@@ -473,9 +502,10 @@ static int write_cnodes(struct ubifs_info *c)
                                               UBI_SHORTTERM);
                         if (err)
                                 return err;
+                        dbg_chk_lpt_sz(c, 2, alen - wlen);
                         err = realloc_lpt_leb(c, &lnum);
                         if (err)
-                                return err;
+                                goto no_space;
                         offs = 0;
                         ubifs_assert(lnum >= c->lpt_first &&
                                      lnum <= c->lpt_last);
@@ -486,6 +516,7 @@ static int write_cnodes(struct ubifs_info *c)
                 done_ltab = 1;
                 ubifs_pack_ltab(c, buf + offs, c->ltab_cmt);
                 offs += c->ltab_sz;
+                dbg_chk_lpt_sz(c, 1, c->ltab_sz);
         }
 
         /* Write remaining data in buffer */
@@ -495,6 +526,12 @@ static int write_cnodes(struct ubifs_info *c)
         err = ubifs_leb_write(c, lnum, buf + from, from, alen, UBI_SHORTTERM);
         if (err)
                 return err;
+
+        dbg_chk_lpt_sz(c, 4, alen - wlen);
+        err = dbg_chk_lpt_sz(c, 3, ALIGN(offs, c->min_io_size));
+        if (err)
+                return err;
+
         c->nhead_lnum = lnum;
         c->nhead_offs = ALIGN(offs, c->min_io_size);
 
@@ -503,7 +540,15 @@ static int write_cnodes(struct ubifs_info *c)
         dbg_lp("LPT ltab is at %d:%d", c->ltab_lnum, c->ltab_offs);
         if (c->big_lpt)
                 dbg_lp("LPT lsave is at %d:%d", c->lsave_lnum, c->lsave_offs);
+
         return 0;
+
+no_space:
+        ubifs_err("LPT out of space mismatch");
+        dbg_err("LPT out of space mismatch at LEB %d:%d needing %d, done_ltab "
+                "%d, done_lsave %d", lnum, offs, len, done_ltab, done_lsave);
+        dbg_dump_lpt_info(c);
+        return err;
 }
 
 /**
@@ -1044,6 +1089,8 @@ static int is_a_node(struct ubifs_info *c, uint8_t *buf, int len)
         int pos = 0, node_type, node_len;
         uint16_t crc, calc_crc;
 
+        if (len < UBIFS_LPT_CRC_BYTES + (UBIFS_LPT_TYPE_BITS + 7) / 8)
+                return 0;
         node_type = ubifs_unpack_bits(&addr, &pos, UBIFS_LPT_TYPE_BITS);
         if (node_type == UBIFS_LPT_NOT_A_NODE)
                 return 0;
@@ -1156,6 +1203,9 @@ int ubifs_lpt_start_commit(struct ubifs_info *c)
         dbg_lp("");
 
         mutex_lock(&c->lp_mutex);
+        err = dbg_chk_lpt_free_spc(c);
+        if (err)
+                goto out;
         err = dbg_check_ltab(c);
         if (err)
                 goto out;
@@ -1645,4 +1695,121 @@ int dbg_check_ltab(struct ubifs_info *c)
         return 0;
 }
 
+/**
+ * dbg_chk_lpt_free_spc - check LPT free space is enough to write entire LPT.
+ * @c: the UBIFS file-system description object
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+int dbg_chk_lpt_free_spc(struct ubifs_info *c)
+{
+        long long free = 0;
+        int i;
+
+        for (i = 0; i < c->lpt_lebs; i++) {
+                if (c->ltab[i].tgc || c->ltab[i].cmt)
+                        continue;
+                if (i + c->lpt_first == c->nhead_lnum)
+                        free += c->leb_size - c->nhead_offs;
+                else if (c->ltab[i].free == c->leb_size)
+                        free += c->leb_size;
+        }
+        if (free < c->lpt_sz) {
+                dbg_err("LPT space error: free %lld lpt_sz %lld",
+                        free, c->lpt_sz);
+                dbg_dump_lpt_info(c);
+                return -EINVAL;
+        }
+        return 0;
+}
+
+/**
+ * dbg_chk_lpt_sz - check LPT does not write more than LPT size.
+ * @c: the UBIFS file-system description object
+ * @action: action
+ * @len: length written
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+int dbg_chk_lpt_sz(struct ubifs_info *c, int action, int len)
+{
+        long long chk_lpt_sz, lpt_sz;
+        int err = 0;
+
+        switch (action) {
+        case 0:
+                c->chk_lpt_sz = 0;
+                c->chk_lpt_sz2 = 0;
+                c->chk_lpt_lebs = 0;
+                c->chk_lpt_wastage = 0;
+                if (c->dirty_pn_cnt > c->pnode_cnt) {
+                        dbg_err("dirty pnodes %d exceed max %d",
+                                c->dirty_pn_cnt, c->pnode_cnt);
+                        err = -EINVAL;
+                }
+                if (c->dirty_nn_cnt > c->nnode_cnt) {
+                        dbg_err("dirty nnodes %d exceed max %d",
+                                c->dirty_nn_cnt, c->nnode_cnt);
+                        err = -EINVAL;
+                }
+                return err;
+        case 1:
+                c->chk_lpt_sz += len;
+                return 0;
+        case 2:
+                c->chk_lpt_sz += len;
+                c->chk_lpt_wastage += len;
+                c->chk_lpt_lebs += 1;
+                return 0;
+        case 3:
+                chk_lpt_sz = c->leb_size;
+                chk_lpt_sz *= c->chk_lpt_lebs;
+                chk_lpt_sz += len - c->nhead_offs;
+                if (c->chk_lpt_sz != chk_lpt_sz) {
+                        dbg_err("LPT wrote %lld but space used was %lld",
+                                c->chk_lpt_sz, chk_lpt_sz);
+                        err = -EINVAL;
+                }
+                if (c->chk_lpt_sz > c->lpt_sz) {
+                        dbg_err("LPT wrote %lld but lpt_sz is %lld",
+                                c->chk_lpt_sz, c->lpt_sz);
+                        err = -EINVAL;
+                }
+                if (c->chk_lpt_sz2 && c->chk_lpt_sz != c->chk_lpt_sz2) {
+                        dbg_err("LPT layout size %lld but wrote %lld",
+                                c->chk_lpt_sz, c->chk_lpt_sz2);
+                        err = -EINVAL;
+                }
+                if (c->chk_lpt_sz2 && c->new_nhead_offs != len) {
+                        dbg_err("LPT new nhead offs: expected %d was %d",
+                                c->new_nhead_offs, len);
+                        err = -EINVAL;
+                }
+                lpt_sz = (long long)c->pnode_cnt * c->pnode_sz;
+                lpt_sz += (long long)c->nnode_cnt * c->nnode_sz;
+                lpt_sz += c->ltab_sz;
+                if (c->big_lpt)
+                        lpt_sz += c->lsave_sz;
+                if (c->chk_lpt_sz - c->chk_lpt_wastage > lpt_sz) {
+                        dbg_err("LPT chk_lpt_sz %lld + waste %lld exceeds %lld",
+                                c->chk_lpt_sz, c->chk_lpt_wastage, lpt_sz);
+                        err = -EINVAL;
+                }
+                if (err)
+                        dbg_dump_lpt_info(c);
+                c->chk_lpt_sz2 = c->chk_lpt_sz;
+                c->chk_lpt_sz = 0;
+                c->chk_lpt_wastage = 0;
+                c->chk_lpt_lebs = 0;
+                c->new_nhead_offs = len;
+                return err;
+        case 4:
+                c->chk_lpt_sz += len;
+                c->chk_lpt_wastage += len;
+                return 0;
+        default:
+                return -EINVAL;
+        }
+}
+
 #endif /* CONFIG_UBIFS_FS_DEBUG */
diff --git a/fs/ubifs/misc.h b/fs/ubifs/misc.h
index 4c12a9215d7f..4fa81d867e41 100644
--- a/fs/ubifs/misc.h
+++ b/fs/ubifs/misc.h
@@ -310,4 +310,31 @@ static inline int ubifs_tnc_lookup(struct ubifs_info *c,
         return ubifs_tnc_locate(c, key, node, NULL, NULL);
 }
 
+/**
+ * ubifs_get_lprops - get reference to LEB properties.
+ * @c: the UBIFS file-system description object
+ *
+ * This function locks lprops. Lprops have to be unlocked by
+ * 'ubifs_release_lprops()'.
+ */
+static inline void ubifs_get_lprops(struct ubifs_info *c)
+{
+        mutex_lock(&c->lp_mutex);
+}
+
+/**
+ * ubifs_release_lprops - release lprops lock.
+ * @c: the UBIFS file-system description object
+ *
+ * This function has to be called after each 'ubifs_get_lprops()' call to
+ * unlock lprops.
+ */
+static inline void ubifs_release_lprops(struct ubifs_info *c)
+{
+        ubifs_assert(mutex_is_locked(&c->lp_mutex));
+        ubifs_assert(c->lst.empty_lebs >= 0 &&
+                     c->lst.empty_lebs <= c->main_lebs);
+        mutex_unlock(&c->lp_mutex);
+}
+
 #endif /* __UBIFS_MISC_H__ */
diff --git a/fs/ubifs/scan.c b/fs/ubifs/scan.c
index acf5c5fffc60..0ed82479b44b 100644
--- a/fs/ubifs/scan.c
+++ b/fs/ubifs/scan.c
@@ -87,7 +87,7 @@ int ubifs_scan_a_node(const struct ubifs_info *c, void *buf, int len, int lnum,
 
         dbg_scan("scanning %s", dbg_ntype(ch->node_type));
 
-        if (ubifs_check_node(c, buf, lnum, offs, quiet))
+        if (ubifs_check_node(c, buf, lnum, offs, quiet, 1))
                 return SCANNED_A_CORRUPT_NODE;
 
         if (ch->node_type == UBIFS_PAD_NODE) {
diff --git a/fs/ubifs/super.c b/fs/ubifs/super.c
index 9a9220333b3b..8780efbf40ac 100644
--- a/fs/ubifs/super.c
+++ b/fs/ubifs/super.c
@@ -401,6 +401,16 @@ static int ubifs_show_options(struct seq_file *s, struct vfsmount *mnt)
         else if (c->mount_opts.unmount_mode == 1)
                 seq_printf(s, ",norm_unmount");
 
+        if (c->mount_opts.bulk_read == 2)
+                seq_printf(s, ",bulk_read");
+        else if (c->mount_opts.bulk_read == 1)
+                seq_printf(s, ",no_bulk_read");
+
+        if (c->mount_opts.chk_data_crc == 2)
+                seq_printf(s, ",chk_data_crc");
+        else if (c->mount_opts.chk_data_crc == 1)
+                seq_printf(s, ",no_chk_data_crc");
+
         return 0;
 }
 
@@ -408,13 +418,26 @@ static int ubifs_sync_fs(struct super_block *sb, int wait)
 {
         struct ubifs_info *c = sb->s_fs_info;
         int i, ret = 0, err;
+        long long bud_bytes;
 
-        if (c->jheads)
+        if (c->jheads) {
                 for (i = 0; i < c->jhead_cnt; i++) {
                         err = ubifs_wbuf_sync(&c->jheads[i].wbuf);
                         if (err && !ret)
                                 ret = err;
                 }
+
+                /* Commit the journal unless it has too little data */
+                spin_lock(&c->buds_lock);
+                bud_bytes = c->bud_bytes;
+                spin_unlock(&c->buds_lock);
+                if (bud_bytes > c->leb_size) {
+                        err = ubifs_run_commit(c);
+                        if (err)
+                                return err;
+                }
+        }
+
         /*
          * We ought to call sync for c->ubi but it does not have one. If it had
          * it would in turn call mtd->sync, however mtd operations are
@@ -538,6 +561,18 @@ static int init_constants_early(struct ubifs_info *c)
          * calculations when reporting free space.
          */
         c->leb_overhead = c->leb_size % UBIFS_MAX_DATA_NODE_SZ;
+        /* Buffer size for bulk-reads */
+        c->bulk_read_buf_size = UBIFS_MAX_BULK_READ * UBIFS_MAX_DATA_NODE_SZ;
+        if (c->bulk_read_buf_size > c->leb_size)
+                c->bulk_read_buf_size = c->leb_size;
+        if (c->bulk_read_buf_size > 128 * 1024) {
+                /* Check if we can kmalloc more than 128KiB */
+                void *try = kmalloc(c->bulk_read_buf_size, GFP_KERNEL);
+
+                kfree(try);
+                if (!try)
+                        c->bulk_read_buf_size = 128 * 1024;
+        }
         return 0;
 }
 
@@ -840,17 +875,29 @@ static int check_volume_empty(struct ubifs_info *c)
  *
  * Opt_fast_unmount: do not run a journal commit before un-mounting
  * Opt_norm_unmount: run a journal commit before un-mounting
+ * Opt_bulk_read: enable bulk-reads
+ * Opt_no_bulk_read: disable bulk-reads
+ * Opt_chk_data_crc: check CRCs when reading data nodes
+ * Opt_no_chk_data_crc: do not check CRCs when reading data nodes
  * Opt_err: just end of array marker
  */
 enum {
         Opt_fast_unmount,
         Opt_norm_unmount,
+        Opt_bulk_read,
+        Opt_no_bulk_read,
+        Opt_chk_data_crc,
+        Opt_no_chk_data_crc,
         Opt_err,
 };
 
 static const match_table_t tokens = {
         {Opt_fast_unmount, "fast_unmount"},
         {Opt_norm_unmount, "norm_unmount"},
+        {Opt_bulk_read, "bulk_read"},
+        {Opt_no_bulk_read, "no_bulk_read"},
+        {Opt_chk_data_crc, "chk_data_crc"},
+        {Opt_no_chk_data_crc, "no_chk_data_crc"},
         {Opt_err, NULL},
 };
 
@@ -888,6 +935,22 @@ static int ubifs_parse_options(struct ubifs_info *c, char *options,
                         c->mount_opts.unmount_mode = 1;
                         c->fast_unmount = 0;
                         break;
+                case Opt_bulk_read:
+                        c->mount_opts.bulk_read = 2;
+                        c->bulk_read = 1;
+                        break;
+                case Opt_no_bulk_read:
+                        c->mount_opts.bulk_read = 1;
+                        c->bulk_read = 0;
+                        break;
+                case Opt_chk_data_crc:
+                        c->mount_opts.chk_data_crc = 2;
+                        c->no_chk_data_crc = 0;
+                        break;
+                case Opt_no_chk_data_crc:
+                        c->mount_opts.chk_data_crc = 1;
+                        c->no_chk_data_crc = 1;
+                        break;
                 default:
                         ubifs_err("unrecognized mount option \"%s\" "
                                   "or missing value", p);
@@ -996,6 +1059,8 @@ static int mount_ubifs(struct ubifs_info *c)
                         goto out_free;
         }
 
+        c->always_chk_crc = 1;
+
         err = ubifs_read_superblock(c);
         if (err)
                 goto out_free;
@@ -1032,8 +1097,6 @@ static int mount_ubifs(struct ubifs_info *c)
 
                 /* Create background thread */
                 c->bgt = kthread_create(ubifs_bg_thread, c, c->bgt_name);
-                if (!c->bgt)
-                        c->bgt = ERR_PTR(-EINVAL);
                 if (IS_ERR(c->bgt)) {
                         err = PTR_ERR(c->bgt);
                         c->bgt = NULL;
@@ -1139,24 +1202,28 @@ static int mount_ubifs(struct ubifs_info *c)
         if (err)
                 goto out_infos;
 
+        c->always_chk_crc = 0;
+
         ubifs_msg("mounted UBI device %d, volume %d, name \"%s\"",
                   c->vi.ubi_num, c->vi.vol_id, c->vi.name);
         if (mounted_read_only)
                 ubifs_msg("mounted read-only");
         x = (long long)c->main_lebs * c->leb_size;
-        ubifs_msg("file system size: %lld bytes (%lld KiB, %lld MiB, %d LEBs)",
-                  x, x >> 10, x >> 20, c->main_lebs);
+        ubifs_msg("file system size:   %lld bytes (%lld KiB, %lld MiB, %d "
+                  "LEBs)", x, x >> 10, x >> 20, c->main_lebs);
         x = (long long)c->log_lebs * c->leb_size + c->max_bud_bytes;
-        ubifs_msg("journal size: %lld bytes (%lld KiB, %lld MiB, %d LEBs)",
-                  x, x >> 10, x >> 20, c->log_lebs + c->max_bud_cnt);
-        ubifs_msg("default compressor: %s", ubifs_compr_name(c->default_compr));
-        ubifs_msg("media format %d, latest format %d",
+        ubifs_msg("journal size:       %lld bytes (%lld KiB, %lld MiB, %d "
+                  "LEBs)", x, x >> 10, x >> 20, c->log_lebs + c->max_bud_cnt);
+        ubifs_msg("media format:       %d (latest is %d)",
                   c->fmt_version, UBIFS_FORMAT_VERSION);
+        ubifs_msg("default compressor: %s", ubifs_compr_name(c->default_compr));
+        ubifs_msg("reserved for root:  %llu bytes (%llu KiB)",
+                c->report_rp_size, c->report_rp_size >> 10);
 
         dbg_msg("compiled on:         " __DATE__ " at " __TIME__);
         dbg_msg("min. I/O unit size:  %d bytes", c->min_io_size);
         dbg_msg("LEB size:            %d bytes (%d KiB)",
-                c->leb_size, c->leb_size / 1024);
+                c->leb_size, c->leb_size >> 10);
         dbg_msg("data journal heads:  %d",
                 c->jhead_cnt - NONDATA_JHEADS_CNT);
         dbg_msg("UUID:                %02X%02X%02X%02X-%02X%02X"
@@ -1282,6 +1349,7 @@ static int ubifs_remount_rw(struct ubifs_info *c)
 
         mutex_lock(&c->umount_mutex);
         c->remounting_rw = 1;
+        c->always_chk_crc = 1;
 
         /* Check for enough free space */
         if (ubifs_calc_available(c, c->min_idx_lebs) <= 0) {
@@ -1345,20 +1413,20 @@ static int ubifs_remount_rw(struct ubifs_info *c)
 
         /* Create background thread */
         c->bgt = kthread_create(ubifs_bg_thread, c, c->bgt_name);
-        if (!c->bgt)
-                c->bgt = ERR_PTR(-EINVAL);
         if (IS_ERR(c->bgt)) {
                 err = PTR_ERR(c->bgt);
                 c->bgt = NULL;
                 ubifs_err("cannot spawn \"%s\", error %d",
                           c->bgt_name, err);
-                return err;
+                goto out;
         }
         wake_up_process(c->bgt);
 
         c->orph_buf = vmalloc(c->leb_size);
-        if (!c->orph_buf)
-                return -ENOMEM;
+        if (!c->orph_buf) {
+                err = -ENOMEM;
+                goto out;
+        }
 
         /* Check for enough log space */
         lnum = c->lhead_lnum + 1;
@@ -1385,6 +1453,7 @@ static int ubifs_remount_rw(struct ubifs_info *c)
         dbg_gen("re-mounted read-write");
         c->vfs_sb->s_flags &= ~MS_RDONLY;
         c->remounting_rw = 0;
+        c->always_chk_crc = 0;
         mutex_unlock(&c->umount_mutex);
         return 0;
 
@@ -1400,6 +1469,7 @@ out:
         c->ileb_buf = NULL;
         ubifs_lpt_free(c, 1);
         c->remounting_rw = 0;
+        c->always_chk_crc = 0;
         mutex_unlock(&c->umount_mutex);
         return err;
 }
@@ -1408,12 +1478,9 @@ out:
  * commit_on_unmount - commit the journal when un-mounting.
  * @c: UBIFS file-system description object
  *
- * This function is called during un-mounting and it commits the journal unless
- * the "fast unmount" mode is enabled. It also avoids committing the journal if
- * it contains too few data.
- *
- * Sometimes recovery requires the journal to be committed at least once, and
- * this function takes care about this.
+ * This function is called during un-mounting and re-mounting, and it commits
+ * the journal unless the "fast unmount" mode is enabled. It also avoids
+ * committing the journal if it contains too few data.
  */
 static void commit_on_unmount(struct ubifs_info *c)
 {
diff --git a/fs/ubifs/tnc.c b/fs/ubifs/tnc.c
index 7634c5970887..d27fd918b9c9 100644
--- a/fs/ubifs/tnc.c
+++ b/fs/ubifs/tnc.c
@@ -284,7 +284,7 @@ static struct ubifs_znode *dirty_cow_znode(struct ubifs_info *c,
         }
 
         zn = copy_znode(c, znode);
-        if (unlikely(IS_ERR(zn)))
+        if (IS_ERR(zn))
                 return zn;
 
         if (zbr->len) {
@@ -470,6 +470,10 @@ static int try_read_node(const struct ubifs_info *c, void *buf, int type,
         if (node_len != len)
                 return 0;
 
+        if (type == UBIFS_DATA_NODE && !c->always_chk_crc)
+                if (c->no_chk_data_crc)
+                        return 0;
+
         crc = crc32(UBIFS_CRC32_INIT, buf + 8, node_len - 8);
         node_crc = le32_to_cpu(ch->crc);
         if (crc != node_crc)
@@ -1128,7 +1132,7 @@ static struct ubifs_znode *dirty_cow_bottom_up(struct ubifs_info *c,
                         ubifs_assert(znode == c->zroot.znode);
                         znode = dirty_cow_znode(c, &c->zroot);
                 }
-                if (unlikely(IS_ERR(znode)) || !p)
+                if (IS_ERR(znode) || !p)
                         break;
                 ubifs_assert(path[p - 1] >= 0);
                 ubifs_assert(path[p - 1] < znode->child_cnt);
@@ -1492,6 +1496,289 @@ out:
 }
 
 /**
+ * ubifs_tnc_get_bu_keys - lookup keys for bulk-read.
+ * @c: UBIFS file-system description object
+ * @bu: bulk-read parameters and results
+ *
+ * Lookup consecutive data node keys for the same inode that reside
+ * consecutively in the same LEB.
+ */
+int ubifs_tnc_get_bu_keys(struct ubifs_info *c, struct bu_info *bu)
+{
+        int n, err = 0, lnum = -1, uninitialized_var(offs);
+        int uninitialized_var(len);
+        unsigned int block = key_block(c, &bu->key);
+        struct ubifs_znode *znode;
+
+        bu->cnt = 0;
+        bu->blk_cnt = 0;
+        bu->eof = 0;
+
+        mutex_lock(&c->tnc_mutex);
+        /* Find first key */
+        err = ubifs_lookup_level0(c, &bu->key, &znode, &n);
+        if (err < 0)
+                goto out;
+        if (err) {
+                /* Key found */
+                len = znode->zbranch[n].len;
+                /* The buffer must be big enough for at least 1 node */
+                if (len > bu->buf_len) {
+                        err = -EINVAL;
+                        goto out;
+                }
+                /* Add this key */
+                bu->zbranch[bu->cnt++] = znode->zbranch[n];
+                bu->blk_cnt += 1;
+                lnum = znode->zbranch[n].lnum;
+                offs = ALIGN(znode->zbranch[n].offs + len, 8);
+        }
+        while (1) {
+                struct ubifs_zbranch *zbr;
+                union ubifs_key *key;
+                unsigned int next_block;
+
+                /* Find next key */
+                err = tnc_next(c, &znode, &n);
+                if (err)
+                        goto out;
+                zbr = &znode->zbranch[n];
+                key = &zbr->key;
+                /* See if there is another data key for this file */
+                if (key_inum(c, key) != key_inum(c, &bu->key) ||
+                    key_type(c, key) != UBIFS_DATA_KEY) {
+                        err = -ENOENT;
+                        goto out;
+                }
+                if (lnum < 0) {
+                        /* First key found */
+                        lnum = zbr->lnum;
+                        offs = ALIGN(zbr->offs + zbr->len, 8);
+                        len = zbr->len;
+                        if (len > bu->buf_len) {
+                                err = -EINVAL;
+                                goto out;
+                        }
+                } else {
+                        /*
+                         * The data nodes must be in consecutive positions in
+                         * the same LEB.
+                         */
+                        if (zbr->lnum != lnum || zbr->offs != offs)
+                                goto out;
+                        offs += ALIGN(zbr->len, 8);
+                        len = ALIGN(len, 8) + zbr->len;
+                        /* Must not exceed buffer length */
+                        if (len > bu->buf_len)
+                                goto out;
+                }
+                /* Allow for holes */
+                next_block = key_block(c, key);
+                bu->blk_cnt += (next_block - block - 1);
+                if (bu->blk_cnt >= UBIFS_MAX_BULK_READ)
+                        goto out;
+                block = next_block;
+                /* Add this key */
+                bu->zbranch[bu->cnt++] = *zbr;
+                bu->blk_cnt += 1;
+                /* See if we have room for more */
+                if (bu->cnt >= UBIFS_MAX_BULK_READ)
+                        goto out;
+                if (bu->blk_cnt >= UBIFS_MAX_BULK_READ)
+                        goto out;
+        }
+out:
+        if (err == -ENOENT) {
+                bu->eof = 1;
+                err = 0;
+        }
+        bu->gc_seq = c->gc_seq;
+        mutex_unlock(&c->tnc_mutex);
+        if (err)
+                return err;
+        /*
+         * An enormous hole could cause bulk-read to encompass too many
+         * page cache pages, so limit the number here.
+         */
+        if (bu->blk_cnt > UBIFS_MAX_BULK_READ)
+                bu->blk_cnt = UBIFS_MAX_BULK_READ;
+        /*
+         * Ensure that bulk-read covers a whole number of page cache
+         * pages.
+         */
+        if (UBIFS_BLOCKS_PER_PAGE == 1 ||
+            !(bu->blk_cnt & (UBIFS_BLOCKS_PER_PAGE - 1)))
+                return 0;
+        if (bu->eof) {
+                /* At the end of file we can round up */
+                bu->blk_cnt += UBIFS_BLOCKS_PER_PAGE - 1;
+                return 0;
+        }
+        /* Exclude data nodes that do not make up a whole page cache page */
+        block = key_block(c, &bu->key) + bu->blk_cnt;
+        block &= ~(UBIFS_BLOCKS_PER_PAGE - 1);
+        while (bu->cnt) {
+                if (key_block(c, &bu->zbranch[bu->cnt - 1].key) < block)
+                        break;
+                bu->cnt -= 1;
+        }
+        return 0;
+}
+
+/**
+ * read_wbuf - bulk-read from a LEB with a wbuf.
+ * @wbuf: wbuf that may overlap the read
+ * @buf: buffer into which to read
+ * @len: read length
+ * @lnum: LEB number from which to read
+ * @offs: offset from which to read
+ *
+ * This functions returns %0 on success or a negative error code on failure.
+ */
+static int read_wbuf(struct ubifs_wbuf *wbuf, void *buf, int len, int lnum,
+                     int offs)
+{
+        const struct ubifs_info *c = wbuf->c;
+        int rlen, overlap;
+
+        dbg_io("LEB %d:%d, length %d", lnum, offs, len);
+        ubifs_assert(wbuf && lnum >= 0 && lnum < c->leb_cnt && offs >= 0);
+        ubifs_assert(!(offs & 7) && offs < c->leb_size);
+        ubifs_assert(offs + len <= c->leb_size);
+
+        spin_lock(&wbuf->lock);
+        overlap = (lnum == wbuf->lnum && offs + len > wbuf->offs);
+        if (!overlap) {
+                /* We may safely unlock the write-buffer and read the data */
+                spin_unlock(&wbuf->lock);
+                return ubi_read(c->ubi, lnum, buf, offs, len);
+        }
+
+        /* Don't read under wbuf */
+        rlen = wbuf->offs - offs;
+        if (rlen < 0)
+                rlen = 0;
+
+        /* Copy the rest from the write-buffer */
+        memcpy(buf + rlen, wbuf->buf + offs + rlen - wbuf->offs, len - rlen);
+        spin_unlock(&wbuf->lock);
+
+        if (rlen > 0)
+                /* Read everything that goes before write-buffer */
+                return ubi_read(c->ubi, lnum, buf, offs, rlen);
+
+        return 0;
+}
+
+/**
+ * validate_data_node - validate data nodes for bulk-read.
+ * @c: UBIFS file-system description object
+ * @buf: buffer containing data node to validate
+ * @zbr: zbranch of data node to validate
+ *
+ * This functions returns %0 on success or a negative error code on failure.
+ */
+static int validate_data_node(struct ubifs_info *c, void *buf,
+                              struct ubifs_zbranch *zbr)
+{
+        union ubifs_key key1;
+        struct ubifs_ch *ch = buf;
+        int err, len;
+
+        if (ch->node_type != UBIFS_DATA_NODE) {
+                ubifs_err("bad node type (%d but expected %d)",
+                          ch->node_type, UBIFS_DATA_NODE);
+                goto out_err;
+        }
+
+        err = ubifs_check_node(c, buf, zbr->lnum, zbr->offs, 0, 0);
+        if (err) {
+                ubifs_err("expected node type %d", UBIFS_DATA_NODE);
+                goto out;
+        }
+
+        len = le32_to_cpu(ch->len);
+        if (len != zbr->len) {
+                ubifs_err("bad node length %d, expected %d", len, zbr->len);
+                goto out_err;
+        }
+
+        /* Make sure the key of the read node is correct */
+        key_read(c, buf + UBIFS_KEY_OFFSET, &key1);
+        if (!keys_eq(c, &zbr->key, &key1)) {
+                ubifs_err("bad key in node at LEB %d:%d",
+                          zbr->lnum, zbr->offs);
+                dbg_tnc("looked for key %s found node's key %s",
+                        DBGKEY(&zbr->key), DBGKEY1(&key1));
+                goto out_err;
+        }
+
+        return 0;
+
+out_err:
+        err = -EINVAL;
+out:
+        ubifs_err("bad node at LEB %d:%d", zbr->lnum, zbr->offs);
+        dbg_dump_node(c, buf);
+        dbg_dump_stack();
+        return err;
+}
+
+/**
+ * ubifs_tnc_bulk_read - read a number of data nodes in one go.
+ * @c: UBIFS file-system description object
+ * @bu: bulk-read parameters and results
+ *
+ * This functions reads and validates the data nodes that were identified by the
+ * 'ubifs_tnc_get_bu_keys()' function. This functions returns %0 on success,
+ * -EAGAIN to indicate a race with GC, or another negative error code on
+ * failure.
+ */
+int ubifs_tnc_bulk_read(struct ubifs_info *c, struct bu_info *bu)
+{
+        int lnum = bu->zbranch[0].lnum, offs = bu->zbranch[0].offs, len, err, i;
+        struct ubifs_wbuf *wbuf;
+        void *buf;
+
+        len = bu->zbranch[bu->cnt - 1].offs;
+        len += bu->zbranch[bu->cnt - 1].len - offs;
+        if (len > bu->buf_len) {
+                ubifs_err("buffer too small %d vs %d", bu->buf_len, len);
+                return -EINVAL;
+        }
+
+        /* Do the read */
+        wbuf = ubifs_get_wbuf(c, lnum);
+        if (wbuf)
+                err = read_wbuf(wbuf, bu->buf, len, lnum, offs);
+        else
+                err = ubi_read(c->ubi, lnum, bu->buf, offs, len);
+
+        /* Check for a race with GC */
+        if (maybe_leb_gced(c, lnum, bu->gc_seq))
+                return -EAGAIN;
+
+        if (err && err != -EBADMSG) {
+                ubifs_err("failed to read from LEB %d:%d, error %d",
+                          lnum, offs, err);
+                dbg_dump_stack();
+                dbg_tnc("key %s", DBGKEY(&bu->key));
+                return err;
+        }
+
+        /* Validate the nodes read */
+        buf = bu->buf;
+        for (i = 0; i < bu->cnt; i++) {
+                err = validate_data_node(c, buf, &bu->zbranch[i]);
+                if (err)
+                        return err;
+                buf = buf + ALIGN(bu->zbranch[i].len, 8);
+        }
+
+        return 0;
+}
+
+/**
  * do_lookup_nm- look up a "hashed" node.
  * @c: UBIFS file-system description object
  * @key: node key to lookup
@@ -1675,7 +1962,7 @@ static int tnc_insert(struct ubifs_info *c, struct ubifs_znode *znode,
 {
         struct ubifs_znode *zn, *zi, *zp;
         int i, keep, move, appending = 0;
-        union ubifs_key *key = &zbr->key;
+        union ubifs_key *key = &zbr->key, *key1;
 
         ubifs_assert(n >= 0 && n <= c->fanout);
 
@@ -1716,20 +2003,33 @@ again:
         zn->level = znode->level;
 
         /* Decide where to split */
-        if (znode->level == 0 && n == c->fanout &&
-            key_type(c, key) == UBIFS_DATA_KEY) {
-                union ubifs_key *key1;
-
-                /*
-                 * If this is an inode which is being appended - do not split
-                 * it because no other zbranches can be inserted between
-                 * zbranches of consecutive data nodes anyway.
-                 */
-                key1 = &znode->zbranch[n - 1].key;
-                if (key_inum(c, key1) == key_inum(c, key) &&
-                    key_type(c, key1) == UBIFS_DATA_KEY &&
-                    key_block(c, key1) == key_block(c, key) - 1)
-                        appending = 1;
+        if (znode->level == 0 && key_type(c, key) == UBIFS_DATA_KEY) {
+                /* Try not to split consecutive data keys */
+                if (n == c->fanout) {
+                        key1 = &znode->zbranch[n - 1].key;
+                        if (key_inum(c, key1) == key_inum(c, key) &&
+                            key_type(c, key1) == UBIFS_DATA_KEY)
+                                appending = 1;
+                } else
+                        goto check_split;
+        } else if (appending && n != c->fanout) {
+                /* Try not to split consecutive data keys */
+                appending = 0;
+check_split:
+                if (n >= (c->fanout + 1) / 2) {
+                        key1 = &znode->zbranch[0].key;
+                        if (key_inum(c, key1) == key_inum(c, key) &&
+                            key_type(c, key1) == UBIFS_DATA_KEY) {
+                                key1 = &znode->zbranch[n].key;
+                                if (key_inum(c, key1) != key_inum(c, key) ||
+                                    key_type(c, key1) != UBIFS_DATA_KEY) {
+                                        keep = n;
+                                        move = c->fanout - keep;
+                                        zi = znode;
+                                        goto do_split;
+                                }
+                        }
+                }
         }
 
         if (appending) {
@@ -1759,6 +2059,8 @@ again:
                         zbr->znode->parent = zn;
         }
 
+do_split:
+
         __set_bit(DIRTY_ZNODE, &zn->flags);
         atomic_long_inc(&c->dirty_zn_cnt);
 
@@ -1785,14 +2087,11 @@ again:
 
         /* Insert new znode (produced by spitting) into the parent */
         if (zp) {
-                i = n;
+                if (n == 0 && zi == znode && znode->iip == 0)
+                        correct_parent_keys(c, znode);
+
                 /* Locate insertion point */
                 n = znode->iip + 1;
-                if (appending && n != c->fanout)
-                        appending = 0;
-
-                if (i == 0 && zi == znode && znode->iip == 0)
-                        correct_parent_keys(c, znode);
 
                 /* Tail recursion */
                 zbr->key = zn->zbranch[0].key;
diff --git a/fs/ubifs/tnc_misc.c b/fs/ubifs/tnc_misc.c
index a25c1cc1f8d9..b48db999903e 100644
--- a/fs/ubifs/tnc_misc.c
+++ b/fs/ubifs/tnc_misc.c
@@ -480,8 +480,8 @@ int ubifs_tnc_read_node(struct ubifs_info *c, struct ubifs_zbranch *zbr,
         }
 
         /* Make sure the key of the read node is correct */
-        key_read(c, key, &key1);
-        if (memcmp(node + UBIFS_KEY_OFFSET, &key1, c->key_len)) {
+        key_read(c, node + UBIFS_KEY_OFFSET, &key1);
+        if (!keys_eq(c, key, &key1)) {
                 ubifs_err("bad key in node at LEB %d:%d",
                           zbr->lnum, zbr->offs);
                 dbg_tnc("looked for key %s found node's key %s",
diff --git a/fs/ubifs/ubifs-media.h b/fs/ubifs/ubifs-media.h
index a9ecbd9af20d..0b378042a3a2 100644
--- a/fs/ubifs/ubifs-media.h
+++ b/fs/ubifs/ubifs-media.h
@@ -75,7 +75,6 @@
  */
 #define UBIFS_BLOCK_SIZE  4096
 #define UBIFS_BLOCK_SHIFT 12
-#define UBIFS_BLOCK_MASK  0x00000FFF
 
 /* UBIFS padding byte pattern (must not be first or last byte of node magic) */
 #define UBIFS_PADDING_BYTE 0xCE
diff --git a/fs/ubifs/ubifs.h b/fs/ubifs/ubifs.h
index 17c620b93eec..a7bd32fa15b9 100644
--- a/fs/ubifs/ubifs.h
+++ b/fs/ubifs/ubifs.h
@@ -142,6 +142,9 @@
 /* Maximum expected tree height for use by bottom_up_buf */
 #define BOTTOM_UP_HEIGHT 64
 
+/* Maximum number of data nodes to bulk-read */
+#define UBIFS_MAX_BULK_READ 32
+
 /*
  * Lockdep classes for UBIFS inode @ui_mutex.
  */
@@ -328,9 +331,10 @@ struct ubifs_gced_idx_leb {
  *               this inode
  * @dirty: non-zero if the inode is dirty
  * @xattr: non-zero if this is an extended attribute inode
+ * @bulk_read: non-zero if bulk-read should be used
  * @ui_mutex: serializes inode write-back with the rest of VFS operations,
- *            serializes "clean <-> dirty" state changes, protects @dirty,
- *            @ui_size, and @xattr_size
+ *            serializes "clean <-> dirty" state changes, serializes bulk-read,
+ *            protects @dirty, @bulk_read, @ui_size, and @xattr_size
  * @ui_lock: protects @synced_i_size
  * @synced_i_size: synchronized size of inode, i.e. the value of inode size
  *                 currently stored on the flash; used only for regular file
@@ -338,6 +342,8 @@ struct ubifs_gced_idx_leb {
  * @ui_size: inode size used by UBIFS when writing to flash
  * @flags: inode flags (@UBIFS_COMPR_FL, etc)
  * @compr_type: default compression type used for this inode
+ * @last_page_read: page number of last page read (for bulk read)
+ * @read_in_a_row: number of consecutive pages read in a row (for bulk read)
  * @data_len: length of the data attached to the inode
  * @data: inode's data
  *
@@ -379,12 +385,15 @@ struct ubifs_inode {
         unsigned int xattr_names;
         unsigned int dirty:1;
         unsigned int xattr:1;
+        unsigned int bulk_read:1;
         struct mutex ui_mutex;
         spinlock_t ui_lock;
         loff_t synced_i_size;
         loff_t ui_size;
         int flags;
         int compr_type;
+        pgoff_t last_page_read;
+        pgoff_t read_in_a_row;
         int data_len;
         void *data;
 };
@@ -698,8 +707,8 @@ struct ubifs_jhead {
  * struct ubifs_zbranch - key/coordinate/length branch stored in znodes.
  * @key: key
  * @znode: znode address in memory
- * @lnum: LEB number of the indexing node
- * @offs: offset of the indexing node within @lnum
+ * @lnum: LEB number of the target node (indexing node or data node)
+ * @offs: target node offset within @lnum
  * @len: target node length
  */
 struct ubifs_zbranch {
@@ -744,6 +753,28 @@ struct ubifs_znode {
 };
 
 /**
+ * struct bu_info - bulk-read information
+ * @key: first data node key
+ * @zbranch: zbranches of data nodes to bulk read
+ * @buf: buffer to read into
+ * @buf_len: buffer length
+ * @gc_seq: GC sequence number to detect races with GC
+ * @cnt: number of data nodes for bulk read
+ * @blk_cnt: number of data blocks including holes
+ * @oef: end of file reached
+ */
+struct bu_info {
+        union ubifs_key key;
+        struct ubifs_zbranch zbranch[UBIFS_MAX_BULK_READ];
+        void *buf;
+        int buf_len;
+        int gc_seq;
+        int cnt;
+        int blk_cnt;
+        int eof;
+};
+
+/**
  * struct ubifs_node_range - node length range description data structure.
  * @len: fixed node length
  * @min_len: minimum possible node length
@@ -862,9 +893,13 @@ struct ubifs_orphan {
 /**
  * struct ubifs_mount_opts - UBIFS-specific mount options information.
  * @unmount_mode: selected unmount mode (%0 default, %1 normal, %2 fast)
+ * @bulk_read: enable bulk-reads
+ * @chk_data_crc: check CRCs when reading data nodes
  */
 struct ubifs_mount_opts {
         unsigned int unmount_mode:2;
+        unsigned int bulk_read:2;
+        unsigned int chk_data_crc:2;
 };
 
 /**
@@ -905,13 +940,12 @@ struct ubifs_mount_opts {
  * @cmt_state: commit state
  * @cs_lock: commit state lock
  * @cmt_wq: wait queue to sleep on if the log is full and a commit is running
+ *
  * @fast_unmount: do not run journal commit before un-mounting
  * @big_lpt: flag that LPT is too big to write whole during commit
- * @check_lpt_free: flag that indicates LPT GC may be needed
- * @nospace: non-zero if the file-system does not have flash space (used as
- *           optimization)
- * @nospace_rp: the same as @nospace, but additionally means that even reserved
- *              pool is full
+ * @no_chk_data_crc: do not check CRCs when reading data nodes (except during
+ *                   recovery)
+ * @bulk_read: enable bulk-reads
  *
  * @tnc_mutex: protects the Tree Node Cache (TNC), @zroot, @cnext, @enext, and
  *             @calc_idx_sz
@@ -935,6 +969,7 @@ struct ubifs_mount_opts {
  * @mst_node: master node
  * @mst_offs: offset of valid master node
  * @mst_mutex: protects the master node area, @mst_node, and @mst_offs
+ * @bulk_read_buf_size: buffer size for bulk-reads
  *
  * @log_lebs: number of logical eraseblocks in the log
  * @log_bytes: log size in bytes
@@ -977,12 +1012,17 @@ struct ubifs_mount_opts {
  *                        but which still have to be taken into account because
  *                        the index has not been committed so far
  * @space_lock: protects @budg_idx_growth, @budg_data_growth, @budg_dd_growth,
- *              @budg_uncommited_idx, @min_idx_lebs, @old_idx_sz, and @lst;
+ *              @budg_uncommited_idx, @min_idx_lebs, @old_idx_sz, @lst,
+ *              @nospace, and @nospace_rp;
  * @min_idx_lebs: minimum number of LEBs required for the index
  * @old_idx_sz: size of index on flash
  * @calc_idx_sz: temporary variable which is used to calculate new index size
  *               (contains accurate new index size at end of TNC commit start)
  * @lst: lprops statistics
+ * @nospace: non-zero if the file-system does not have flash space (used as
+ *           optimization)
+ * @nospace_rp: the same as @nospace, but additionally means that even reserved
+ *              pool is full
  *
  * @page_budget: budget for a page
  * @inode_budget: budget for an inode
@@ -1061,6 +1101,7 @@ struct ubifs_mount_opts {
  * @lpt_drty_flgs: dirty flags for LPT special nodes e.g. ltab
  * @dirty_nn_cnt: number of dirty nnodes
  * @dirty_pn_cnt: number of dirty pnodes
+ * @check_lpt_free: flag that indicates LPT GC may be needed
  * @lpt_sz: LPT size
  * @lpt_nod_buf: buffer for an on-flash nnode or pnode
  * @lpt_buf: buffer of LEB size used by LPT
@@ -1102,6 +1143,7 @@ struct ubifs_mount_opts {
  * @rcvrd_mst_node: recovered master node to write when mounting ro to rw
  * @size_tree: inode size information for recovery
  * @remounting_rw: set while remounting from ro to rw (sb flags have MS_RDONLY)
+ * @always_chk_crc: always check CRCs (while mounting and remounting rw)
  * @mount_opts: UBIFS-specific mount options
  *
  * @dbg_buf: a buffer of LEB size used for debugging purposes
@@ -1146,11 +1188,11 @@ struct ubifs_info {
         int cmt_state;
         spinlock_t cs_lock;
         wait_queue_head_t cmt_wq;
+
         unsigned int fast_unmount:1;
         unsigned int big_lpt:1;
-        unsigned int check_lpt_free:1;
-        unsigned int nospace:1;
-        unsigned int nospace_rp:1;
+        unsigned int no_chk_data_crc:1;
+        unsigned int bulk_read:1;
 
         struct mutex tnc_mutex;
         struct ubifs_zbranch zroot;
@@ -1175,6 +1217,7 @@ struct ubifs_info {
         struct ubifs_mst_node *mst_node;
         int mst_offs;
         struct mutex mst_mutex;
+        int bulk_read_buf_size;
 
         int log_lebs;
         long long log_bytes;
@@ -1218,6 +1261,8 @@ struct ubifs_info {
         unsigned long long old_idx_sz;
         unsigned long long calc_idx_sz;
         struct ubifs_lp_stats lst;
+        unsigned int nospace:1;
+        unsigned int nospace_rp:1;
 
         int page_budget;
         int inode_budget;
@@ -1294,6 +1339,7 @@ struct ubifs_info {
         int lpt_drty_flgs;
         int dirty_nn_cnt;
         int dirty_pn_cnt;
+        int check_lpt_free;
         long long lpt_sz;
         void *lpt_nod_buf;
         void *lpt_buf;
@@ -1335,6 +1381,7 @@ struct ubifs_info {
         struct ubifs_mst_node *rcvrd_mst_node;
         struct rb_root size_tree;
         int remounting_rw;
+        int always_chk_crc;
         struct ubifs_mount_opts mount_opts;
 
 #ifdef CONFIG_UBIFS_FS_DEBUG
@@ -1347,6 +1394,12 @@ struct ubifs_info {
         unsigned long fail_timeout;
         unsigned int fail_cnt;
         unsigned int fail_cnt_max;
+        long long chk_lpt_sz;
+        long long chk_lpt_sz2;
+        long long chk_lpt_wastage;
+        int chk_lpt_lebs;
+        int new_nhead_lnum;
+        int new_nhead_offs;
 #endif
 };
 
@@ -1377,7 +1430,7 @@ int ubifs_read_node_wbuf(struct ubifs_wbuf *wbuf, void *buf, int type, int len,
 int ubifs_write_node(struct ubifs_info *c, void *node, int len, int lnum,
                      int offs, int dtype);
 int ubifs_check_node(const struct ubifs_info *c, const void *buf, int lnum,
-                     int offs, int quiet);
+                     int offs, int quiet, int chk_crc);
 void ubifs_prepare_node(struct ubifs_info *c, void *buf, int len, int pad);
 void ubifs_prep_grp_node(struct ubifs_info *c, void *node, int len, int last);
 int ubifs_io_init(struct ubifs_info *c);
@@ -1490,6 +1543,8 @@ void destroy_old_idx(struct ubifs_info *c);
 int is_idx_node_in_tnc(struct ubifs_info *c, union ubifs_key *key, int level,
                        int lnum, int offs);
 int insert_old_idx_znode(struct ubifs_info *c, struct ubifs_znode *znode);
+int ubifs_tnc_get_bu_keys(struct ubifs_info *c, struct bu_info *bu);
+int ubifs_tnc_bulk_read(struct ubifs_info *c, struct bu_info *bu);
 
 /* tnc_misc.c */
 struct ubifs_znode *ubifs_tnc_levelorder_next(struct ubifs_znode *zr,
@@ -1586,12 +1641,10 @@ int ubifs_lpt_post_commit(struct ubifs_info *c);
 void ubifs_lpt_free(struct ubifs_info *c, int wr_only);
 
 /* lprops.c */
-void ubifs_get_lprops(struct ubifs_info *c);
 const struct ubifs_lprops *ubifs_change_lp(struct ubifs_info *c,
                                            const struct ubifs_lprops *lp,
                                            int free, int dirty, int flags,
                                            int idx_gc_cnt);
-void ubifs_release_lprops(struct ubifs_info *c);
 void ubifs_get_lp_stats(struct ubifs_info *c, struct ubifs_lp_stats *stats);
 void ubifs_add_to_cat(struct ubifs_info *c, struct ubifs_lprops *lprops,
                       int cat);
diff --git a/fs/ubifs/xattr.c b/fs/ubifs/xattr.c
index 649bec78b645..cfd31e229c89 100644
--- a/fs/ubifs/xattr.c
+++ b/fs/ubifs/xattr.c
@@ -446,7 +446,7 @@ ssize_t ubifs_listxattr(struct dentry *dentry, char *buffer, size_t size)
                 int type;
 
                 xent = ubifs_tnc_next_ent(c, &key, &nm);
-                if (unlikely(IS_ERR(xent))) {
+                if (IS_ERR(xent)) {
                         err = PTR_ERR(xent);
                         break;
                 }