Merge branch 'integrity-check-patch-v2' of git://btrfs.giantdisaster.de/git/btrfs into integration

Conflicts:
	fs/btrfs/ctree.h
	fs/btrfs/super.c
Signed-off-by: Chris Mason <chris.mason@oracle.com>

fs/btrfs/Kconfig

@@ -31,3 +31,22 @@ config BTRFS_FS_POSIX_ACL
 	  Linux website <http://acl.bestbits.at/>.
 
 	  If you don't know what Access Control Lists are, say N
+
+config BTRFS_FS_CHECK_INTEGRITY
+	bool "Btrfs with integrity check tool compiled in (DANGEROUS)"
+	depends on BTRFS_FS
+	help
+	  Adds code that examines all block write requests (including
+	  writes of the super block). The goal is to verify that the
+	  state of the filesystem on disk is always consistent, i.e.,
+	  after a power-loss or kernel panic event the filesystem is
+	  in a consistent state.
+
+	  If the integrity check tool is included and activated in
+	  the mount options, plenty of kernel memory is used, and
+	  plenty of additional CPU cycles are spent. Enabling this
+	  functionality is not intended for normal use.
+
+	  In most cases, unless you are a btrfs developer who needs
+	  to verify the integrity of (super)-block write requests
+	  during the run of a regression test, say N

fs/btrfs/Makefile

@@ -11,3 +11,4 @@ btrfs-y += super.o ctree.o extent-tree.o print-tree.o root-tree.o dir-item.o \
 	   reada.o backref.o ulist.o
 
 btrfs-$(CONFIG_BTRFS_FS_POSIX_ACL) += acl.o
+btrfs-$(CONFIG_BTRFS_FS_CHECK_INTEGRITY) += check-integrity.o

fs/btrfs/check-integrity.h

+/*
+ * Copyright (C) STRATO AG 2011.  All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public
+ * License v2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public
+ * License along with this program; if not, write to the
+ * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ * Boston, MA 021110-1307, USA.
+ */
+
+#if !defined(__BTRFS_CHECK_INTEGRITY__)
+#define __BTRFS_CHECK_INTEGRITY__
+
+#ifdef CONFIG_BTRFS_FS_CHECK_INTEGRITY
+int btrfsic_submit_bh(int rw, struct buffer_head *bh);
+void btrfsic_submit_bio(int rw, struct bio *bio);
+#else
+#define btrfsic_submit_bh submit_bh
+#define btrfsic_submit_bio submit_bio
+#endif
+
+int btrfsic_mount(struct btrfs_root *root,
+		  struct btrfs_fs_devices *fs_devices,
+		  int including_extent_data, u32 print_mask);
+void btrfsic_unmount(struct btrfs_root *root,
+		     struct btrfs_fs_devices *fs_devices);
+
+#endif

fs/btrfs/ctree.h

@@ -1041,7 +1041,7 @@ struct btrfs_fs_info {
 	 * 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;
@@ -1236,6 +1236,10 @@ struct btrfs_fs_info {
 	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;
 
@@ -1497,6 +1501,8 @@ struct btrfs_ioctl_defrag_range_args {
 #define BTRFS_MOUNT_INODE_MAP_CACHE	(1 << 17)
 #define BTRFS_MOUNT_RECOVERY		(1 << 18)
 #define BTRFS_MOUNT_SKIP_BALANCE	(1 << 19)
+#define BTRFS_MOUNT_CHECK_INTEGRITY	(1 << 20)
+#define BTRFS_MOUNT_CHECK_INTEGRITY_INCLUDING_EXTENT_DATA (1 << 21)
 
 #define btrfs_clear_opt(o, opt)		((o) &= ~BTRFS_MOUNT_##opt)
 #define btrfs_set_opt(o, opt)		((o) |= BTRFS_MOUNT_##opt)

fs/btrfs/disk-io.c

@@ -43,6 +43,7 @@
 #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);
@@ -2002,6 +2003,9 @@ struct btrfs_root *open_ctree(struct super_block *sb,
 	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
 
 	spin_lock_init(&fs_info->balance_lock);
 	mutex_init(&fs_info->balance_mutex);
@@ -2360,6 +2364,19 @@ struct btrfs_root *open_ctree(struct super_block *sb,
 		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)) {
@@ -2642,7 +2659,7 @@ static int write_dev_supers(struct btrfs_device *device,
 		 * 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++;
 	}
@@ -2719,7 +2736,7 @@ static int write_dev_flush(struct btrfs_device *device, int wait)
 	device->flush_bio = bio;
 
 	bio_get(bio);
-	submit_bio(WRITE_FLUSH, bio);
+	btrfsic_submit_bio(WRITE_FLUSH, bio);
 
 	return 0;
 }
@@ -3068,6 +3085,11 @@ int close_ctree(struct btrfs_root *root)
 	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);
 

fs/btrfs/extent_io.c

@@ -18,6 +18,7 @@
 #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;
@@ -1895,7 +1896,7 @@ int repair_io_failure(struct btrfs_mapping_tree *map_tree, u64 start,
 	}
 	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)) {
@@ -2393,7 +2394,7 @@ static int submit_one_bio(int rw, struct bio *bio, int mirror_num,
 		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;

fs/btrfs/scrub.c

@@ -25,6 +25,7 @@
 #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
@@ -733,7 +734,7 @@ static int scrub_fixup_io(int rw, struct block_device *bdev, sector_t sector,
 	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);
@@ -959,7 +960,7 @@ static int scrub_submit(struct scrub_dev *sdev)
 	sdev->curr = -1;
 	atomic_inc(&sdev->in_flight);
 
-	submit_bio(READ, sbio->bio);
+	btrfsic_submit_bio(READ, sbio->bio);
 
 	return 0;
 }

fs/btrfs/super.c

@@ -166,6 +166,8 @@ enum {
 	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_skip_balance,
+	Opt_check_integrity, Opt_check_integrity_including_extent_data,
+	Opt_check_integrity_print_mask,
 	Opt_err,
 };
 
@@ -202,6 +204,9 @@ static match_table_t tokens = {
 	{Opt_no_space_cache, "nospace_cache"},
 	{Opt_recovery, "recovery"},
 	{Opt_skip_balance, "skip_balance"},
+	{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},
 };
 
@@ -403,6 +408,37 @@ int btrfs_parse_options(struct btrfs_root *root, char *options)
 		case Opt_skip_balance:
 			btrfs_set_opt(info->mount_opt, SKIP_BALANCE);
 			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);

fs/btrfs/volumes.c

@@ -33,6 +33,7 @@
 #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,
@@ -247,7 +248,7 @@ static noinline int run_scheduled_bios(struct btrfs_device *device)
 			sync_pending = 0;
 		}
 
-		submit_bio(cur->bi_rw, cur);
+		btrfsic_submit_bio(cur->bi_rw, cur);
 		num_run++;
 		batch_run++;
 		if (need_resched())
@@ -3962,7 +3963,7 @@ static noinline int schedule_bio(struct btrfs_root *root,
 	/* 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;
 	}
@@ -4057,7 +4058,7 @@ int btrfs_map_bio(struct btrfs_root *root, int rw, struct bio *bio,
 			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;