* is required instead of the faster short fsync log commits
         */
        u64 last_trans_log_full_commit;
-       unsigned long mount_opt:20;
+       unsigned long mount_opt:21;
        unsigned long compress_type:4;
        u64 max_inline;
        u64 alloc_start;
        int scrub_workers_refcnt;
        struct btrfs_workers scrub_workers;
 
+#ifdef CONFIG_BTRFS_FS_CHECK_INTEGRITY
+       u32 check_integrity_print_mask;
+#endif
+
        /* filesystem state */
        u64 fs_state;
 
 #define BTRFS_MOUNT_AUTO_DEFRAG                (1 << 16)
 #define BTRFS_MOUNT_INODE_MAP_CACHE    (1 << 17)
 #define BTRFS_MOUNT_RECOVERY           (1 << 18)
+#define BTRFS_MOUNT_CHECK_INTEGRITY    (1 << 19)
+#define BTRFS_MOUNT_CHECK_INTEGRITY_INCLUDING_EXTENT_DATA (1 << 20)
 
 #define btrfs_clear_opt(o, opt)                ((o) &= ~BTRFS_MOUNT_##opt)
 #define btrfs_set_opt(o, opt)          ((o) |= BTRFS_MOUNT_##opt)
 
 #include "tree-log.h"
 #include "free-space-cache.h"
 #include "inode-map.h"
+#include "check-integrity.h"
 
 static struct extent_io_ops btree_extent_io_ops;
 static void end_workqueue_fn(struct btrfs_work *work);
        init_waitqueue_head(&fs_info->scrub_pause_wait);
        init_rwsem(&fs_info->scrub_super_lock);
        fs_info->scrub_workers_refcnt = 0;
+#ifdef CONFIG_BTRFS_FS_CHECK_INTEGRITY
+       fs_info->check_integrity_print_mask = 0;
+#endif
 
        sb->s_blocksize = 4096;
        sb->s_blocksize_bits = blksize_bits(4096);
                btrfs_set_opt(fs_info->mount_opt, SSD);
        }
 
+#ifdef CONFIG_BTRFS_FS_CHECK_INTEGRITY
+       if (btrfs_test_opt(tree_root, CHECK_INTEGRITY)) {
+               ret = btrfsic_mount(tree_root, fs_devices,
+                                   btrfs_test_opt(tree_root,
+                                       CHECK_INTEGRITY_INCLUDING_EXTENT_DATA) ?
+                                   1 : 0,
+                                   fs_info->check_integrity_print_mask);
+               if (ret)
+                       printk(KERN_WARNING "btrfs: failed to initialize"
+                              " integrity check module %s\n", sb->s_id);
+       }
+#endif
+
        /* do not make disk changes in broken FS */
        if (btrfs_super_log_root(disk_super) != 0 &&
            !(fs_info->fs_state & BTRFS_SUPER_FLAG_ERROR)) {
                 * we fua the first super.  The others we allow
                 * to go down lazy.
                 */
-               ret = submit_bh(WRITE_FUA, bh);
+               ret = btrfsic_submit_bh(WRITE_FUA, bh);
                if (ret)
                        errors++;
        }
        device->flush_bio = bio;
 
        bio_get(bio);
-       submit_bio(WRITE_FLUSH, bio);
+       btrfsic_submit_bio(WRITE_FLUSH, bio);
 
        return 0;
 }
        btrfs_stop_workers(&fs_info->caching_workers);
        btrfs_stop_workers(&fs_info->readahead_workers);
 
+#ifdef CONFIG_BTRFS_FS_CHECK_INTEGRITY
+       if (btrfs_test_opt(root, CHECK_INTEGRITY))
+               btrfsic_unmount(root, fs_info->fs_devices);
+#endif
+
        btrfs_close_devices(fs_info->fs_devices);
        btrfs_mapping_tree_free(&fs_info->mapping_tree);
 
 
 #include "ctree.h"
 #include "btrfs_inode.h"
 #include "volumes.h"
+#include "check-integrity.h"
 
 static struct kmem_cache *extent_state_cache;
 static struct kmem_cache *extent_buffer_cache;
        }
        bio->bi_bdev = dev->bdev;
        bio_add_page(bio, page, length, start-page_offset(page));
-       submit_bio(WRITE_SYNC, bio);
+       btrfsic_submit_bio(WRITE_SYNC, bio);
        wait_for_completion(&compl);
 
        if (!test_bit(BIO_UPTODATE, &bio->bi_flags)) {
                ret = tree->ops->submit_bio_hook(page->mapping->host, rw, bio,
                                           mirror_num, bio_flags, start);
        else
-               submit_bio(rw, bio);
+               btrfsic_submit_bio(rw, bio);
 
        if (bio_flagged(bio, BIO_EOPNOTSUPP))
                ret = -EOPNOTSUPP;
 
 #include "transaction.h"
 #include "backref.h"
 #include "extent_io.h"
+#include "check-integrity.h"
 
 /*
  * This is only the first step towards a full-features scrub. It reads all
        bio_add_page(bio, page, PAGE_SIZE, 0);
        bio->bi_end_io = scrub_fixup_end_io;
        bio->bi_private = &complete;
-       submit_bio(rw, bio);
+       btrfsic_submit_bio(rw, bio);
 
        /* this will also unplug the queue */
        wait_for_completion(&complete);
        sdev->curr = -1;
        atomic_inc(&sdev->in_flight);
 
-       submit_bio(READ, sbio->bio);
+       btrfsic_submit_bio(READ, sbio->bio);
 
        return 0;
 }
 
        Opt_notreelog, Opt_ratio, Opt_flushoncommit, Opt_discard,
        Opt_space_cache, Opt_clear_cache, Opt_user_subvol_rm_allowed,
        Opt_enospc_debug, Opt_subvolrootid, Opt_defrag,
-       Opt_inode_cache, Opt_no_space_cache, Opt_recovery, Opt_err,
+       Opt_inode_cache, Opt_no_space_cache, Opt_recovery,
+       Opt_check_integrity, Opt_check_integrity_including_extent_data,
+       Opt_check_integrity_print_mask,
+       Opt_err,
 };
 
 static match_table_t tokens = {
        {Opt_inode_cache, "inode_cache"},
        {Opt_no_space_cache, "nospace_cache"},
        {Opt_recovery, "recovery"},
+       {Opt_check_integrity, "check_int"},
+       {Opt_check_integrity_including_extent_data, "check_int_data"},
+       {Opt_check_integrity_print_mask, "check_int_print_mask=%d"},
        {Opt_err, NULL},
 };
 
                        printk(KERN_INFO "btrfs: enabling auto recovery");
                        btrfs_set_opt(info->mount_opt, RECOVERY);
                        break;
+#ifdef CONFIG_BTRFS_FS_CHECK_INTEGRITY
+               case Opt_check_integrity_including_extent_data:
+                       printk(KERN_INFO "btrfs: enabling check integrity"
+                              " including extent data\n");
+                       btrfs_set_opt(info->mount_opt,
+                                     CHECK_INTEGRITY_INCLUDING_EXTENT_DATA);
+                       btrfs_set_opt(info->mount_opt, CHECK_INTEGRITY);
+                       break;
+               case Opt_check_integrity:
+                       printk(KERN_INFO "btrfs: enabling check integrity\n");
+                       btrfs_set_opt(info->mount_opt, CHECK_INTEGRITY);
+                       break;
+               case Opt_check_integrity_print_mask:
+                       intarg = 0;
+                       match_int(&args[0], &intarg);
+                       if (intarg) {
+                               info->check_integrity_print_mask = intarg;
+                               printk(KERN_INFO "btrfs:"
+                                      " check_integrity_print_mask 0x%x\n",
+                                      info->check_integrity_print_mask);
+                       }
+                       break;
+#else
+               case Opt_check_integrity_including_extent_data:
+               case Opt_check_integrity:
+               case Opt_check_integrity_print_mask:
+                       printk(KERN_ERR "btrfs: support for check_integrity*"
+                              " not compiled in!\n");
+                       ret = -EINVAL;
+                       goto out;
+#endif
                case Opt_err:
                        printk(KERN_INFO "btrfs: unrecognized mount option "
                               "'%s'\n", p);
 
 #include "print-tree.h"
 #include "volumes.h"
 #include "async-thread.h"
+#include "check-integrity.h"
 
 static int init_first_rw_device(struct btrfs_trans_handle *trans,
                                struct btrfs_root *root,
                        sync_pending = 0;
                }
 
-               submit_bio(cur->bi_rw, cur);
+               btrfsic_submit_bio(cur->bi_rw, cur);
                num_run++;
                batch_run++;
                if (need_resched())
        /* don't bother with additional async steps for reads, right now */
        if (!(rw & REQ_WRITE)) {
                bio_get(bio);
-               submit_bio(rw, bio);
+               btrfsic_submit_bio(rw, bio);
                bio_put(bio);
                return 0;
        }
                        if (async_submit)
                                schedule_bio(root, dev, rw, bio);
                        else
-                               submit_bio(rw, bio);
+                               btrfsic_submit_bio(rw, bio);
                } else {
                        bio->bi_bdev = root->fs_info->fs_devices->latest_bdev;
                        bio->bi_sector = logical >> 9;