21 files changed, 72 insertions, 297 deletions

diff --git a/Documentation/filesystems/btrfs.txt b/Documentation/filesystems/btrfs.txt
index 6593d2e415c5..f9dad22d95ce 100644
--- a/Documentation/filesystems/btrfs.txt
+++ b/Documentation/filesystems/btrfs.txt
@@ -1,20 +1,10 @@
-
 BTRFS
 =====
 
-Btrfs is a copy on write filesystem for Linux aimed at
-implementing advanced features while focusing on fault tolerance,
-repair and easy administration. Initially developed by Oracle, Btrfs
-is licensed under the GPL and open for contribution from anyone.
-
-Linux has a wealth of filesystems to choose from, but we are facing a
-number of challenges with scaling to the large storage subsystems that
-are becoming common in today's data centers. Filesystems need to scale
-in their ability to address and manage large storage, and also in
-their ability to detect, repair and tolerate errors in the data stored
-on disk.  Btrfs is under heavy development, and is not suitable for
-any uses other than benchmarking and review. The Btrfs disk format is
-not yet finalized.
+Btrfs is a copy on write filesystem for Linux aimed at implementing advanced
+features while focusing on fault tolerance, repair and easy administration.
+Jointly developed by several companies, licensed under the GPL and open for
+contribution from anyone.
 
 The main Btrfs features include:
 
@@ -28,256 +18,14 @@ The main Btrfs features include:
     * Checksums on data and metadata (multiple algorithms available)
     * Compression
     * Integrated multiple device support, with several raid algorithms
-    * Online filesystem check (not yet implemented)
-    * Very fast offline filesystem check
-    * Efficient incremental backup and FS mirroring (not yet implemented)
+    * Offline filesystem check
+    * Efficient incremental backup and FS mirroring
     * Online filesystem defragmentation
 
+For more information please refer to the wiki
 
-Mount Options
-=============
-
-When mounting a btrfs filesystem, the following option are accepted.
-Options with (*) are default options and will not show in the mount options.
-
-  alloc_start=<bytes>
-	Debugging option to force all block allocations above a certain
-	byte threshold on each block device.  The value is specified in
-	bytes, optionally with a K, M, or G suffix, case insensitive.
-	Default is 1MB.
-
-  noautodefrag(*)
-  autodefrag
-	Disable/enable auto defragmentation.
-	Auto defragmentation detects small random writes into files and queue
-	them up for the defrag process.  Works best for small files;
-	Not well suited for large database workloads.
-
-  check_int
-  check_int_data
-  check_int_print_mask=<value>
-	These debugging options control the behavior of the integrity checking
-	module (the BTRFS_FS_CHECK_INTEGRITY config option required).
-
-	check_int enables the integrity checker module, which examines all
-	block write requests to ensure on-disk consistency, at a large
-	memory and CPU cost.
-
-	check_int_data includes extent data in the integrity checks, and
-	implies the check_int option.
-
-	check_int_print_mask takes a bitmask of BTRFSIC_PRINT_MASK_* values
-	as defined in fs/btrfs/check-integrity.c, to control the integrity
-	checker module behavior.
-
-	See comments at the top of fs/btrfs/check-integrity.c for more info.
-
-  commit=<seconds>
-	Set the interval of periodic commit, 30 seconds by default. Higher
-	values defer data being synced to permanent storage with obvious
-	consequences when the system crashes. The upper bound is not forced,
-	but a warning is printed if it's more than 300 seconds (5 minutes).
-
-  compress
-  compress=<type>
-  compress-force
-  compress-force=<type>
-	Control BTRFS file data compression.  Type may be specified as "zlib"
-	"lzo" or "no" (for no compression, used for remounting).  If no type
-	is specified, zlib is used.  If compress-force is specified,
-	all files will be compressed, whether or not they compress well.
-	If compression is enabled, nodatacow and nodatasum are disabled.
-
-  degraded
-	Allow mounts to continue with missing devices.  A read-write mount may
-	fail with too many devices missing, for example if a stripe member
-	is completely missing.
-
-  device=<devicepath>
-	Specify a device during mount so that ioctls on the control device
-	can be avoided.  Especially useful when trying to mount a multi-device
-	setup as root.  May be specified multiple times for multiple devices.
-
-  nodiscard(*)
-  discard
-	Disable/enable discard mount option.
-	Discard issues frequent commands to let the block device reclaim space
-	freed by the filesystem.
-	This is useful for SSD devices, thinly provisioned
-	LUNs and virtual machine images, but may have a significant
-	performance impact.  (The fstrim command is also available to
-	initiate batch trims from userspace).
-
-  noenospc_debug(*)
-  enospc_debug
-	Disable/enable debugging option to be more verbose in some ENOSPC conditions.
-
-  fatal_errors=<action>
-	Action to take when encountering a fatal error:
-	  "bug" - BUG() on a fatal error.  This is the default.
-	  "panic" - panic() on a fatal error.
-
-  noflushoncommit(*)
-  flushoncommit
-	The 'flushoncommit' mount option forces any data dirtied by a write in a
-	prior transaction to commit as part of the current commit.  This makes
-	the committed state a fully consistent view of the file system from the
-	application's perspective (i.e., it includes all completed file system
-	operations).  This was previously the behavior only when a snapshot is
-	created.
-
-  inode_cache
-	Enable free inode number caching.   Defaults to off due to an overflow
-	problem when the free space crcs don't fit inside a single page.
-
-  max_inline=<bytes>
-	Specify the maximum amount of space, in bytes, that can be inlined in
-	a metadata B-tree leaf.  The value is specified in bytes, optionally
-	with a K, M, or G suffix, case insensitive.  In practice, this value
-	is limited by the root sector size, with some space unavailable due
-	to leaf headers.  For a 4k sector size, max inline data is ~3900 bytes.
-
-  metadata_ratio=<value>
-	Specify that 1 metadata chunk should be allocated after every <value>
-	data chunks.  Off by default.
-
-  acl(*)
-  noacl
-	Enable/disable support for Posix Access Control Lists (ACLs).  See the
-	acl(5) manual page for more information about ACLs.
-
-  barrier(*)
-  nobarrier
-        Enable/disable the use of block layer write barriers.  Write barriers
-	ensure that certain IOs make it through the device cache and are on
-	persistent storage. If disabled on a device with a volatile
-	(non-battery-backed) write-back cache, nobarrier option will lead to
-	filesystem corruption on a system crash or power loss.
-
-  datacow(*)
-  nodatacow
-	Enable/disable data copy-on-write for newly created files.
-	Nodatacow implies nodatasum, and disables all compression.
-
-  datasum(*)
-  nodatasum
-	Enable/disable data checksumming for newly created files.
-	Datasum implies datacow.
-
-  treelog(*)
-  notreelog
-	Enable/disable the tree logging used for fsync and O_SYNC writes.
-
-  nologreplay
-	Disable the log tree replay at mount time to prevent filesystem
-	from getting modified.
-	Must be used with 'ro' mount option.
-	A filesystem mounted with this option cannot transition to a
-	read-write mount via remount,rw - the filesystem must be unmounted
-	and mounted back again if read-write access is desired.
-
-  usebackuproot
-	Enable attempts to use backup tree roots if a bad tree root is found at
-	mount time.
-	Currently this scans a list of 4 previous tree roots and tries to
-	use the first readable.
-	And since the mount option doesn't affect any behavior after mount,
-	it won't be shown in mount info.
-	Prior to 4.6, this was done by 'recovery' option that has been
-	deprecated, but will work.
-
-  rescan_uuid_tree
-	Force check and rebuild procedure of the UUID tree. This should not
-	normally be needed.
-
-  skip_balance
-	Skip automatic resume of interrupted balance operation after mount.
-	May be resumed with "btrfs balance resume."
-
-  space_cache (*)
-	Enable the on-disk freespace cache.
-  nospace_cache
-	Disable freespace cache loading without clearing the cache.
-  clear_cache
-	Force clearing and rebuilding of the disk space cache if something
-	has gone wrong.
-
-  ssd
-  nossd
-  ssd_spread
-	Options to control ssd allocation schemes.  By default, BTRFS will
-	enable or disable ssd allocation heuristics depending on whether a
-	rotational or non-rotational disk is in use.  The ssd and nossd options
-	can override this autodetection.
-
-	The ssd_spread mount option attempts to allocate into big chunks
-	of unused space, and may perform better on low-end ssds.  ssd_spread
-	implies ssd, enabling all other ssd heuristics as well.
-
-  subvol=<path>
-	Mount subvolume at <path> rather than the root subvolume.  <path> is
-	relative to the top level subvolume.
-
-  subvolid=<ID>
-	Mount subvolume specified by an ID number rather than the root subvolume.
-	This allows mounting of subvolumes which are not in the root of the mounted
-	filesystem.
-	You can use "btrfs subvolume list" to see subvolume ID numbers.
-
-  subvolrootid=<objectid> (deprecated)
-	Mount subvolume specified by <objectid> rather than the root subvolume.
-	This allows mounting of subvolumes which are not in the root of the mounted
-	filesystem.
-	You can use "btrfs subvolume show " to see the object ID for a subvolume.
-
-  thread_pool=<number>
-	The number of worker threads to allocate.  The default number is equal
-	to the number of CPUs + 2, or 8, whichever is smaller.
-
-  user_subvol_rm_allowed
-	Allow subvolumes to be deleted by a non-root user. Use with caution.
-
-MAILING LIST
-============
-
-There is a Btrfs mailing list hosted on vger.kernel.org. You can
-find details on how to subscribe here:
-
-http://vger.kernel.org/vger-lists.html#linux-btrfs
-
-Mailing list archives are available from gmane:
-
-http://dir.gmane.org/gmane.comp.file-systems.btrfs
-
-
-
-IRC
-===
-
-Discussion of Btrfs also occurs on the #btrfs channel of the Freenode
-IRC network.
-
-
-
-	UTILITIES
-	=========
-
-Userspace tools for creating and manipulating Btrfs file systems are
-available from the git repository at the following location:
-
- http://git.kernel.org/?p=linux/kernel/git/mason/btrfs-progs.git
- git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-progs.git
-
-These include the following tools:
-
-* mkfs.btrfs: create a filesystem
-
-* btrfs: a single tool to manage the filesystems, refer to the manpage for more details
-
-* 'btrfsck' or 'btrfs check': do a consistency check of the filesystem
-
-Other tools for specific tasks:
-
-* btrfs-convert: in-place conversion from ext2/3/4 filesystems
+  https://btrfs.wiki.kernel.org
 
-* btrfs-image: dump filesystem metadata for debugging
+that maintains information about administration tasks, frequently asked
+questions, use cases, mount options, comprehensible changelogs, features,
+manual pages, source code repositories, contacts etc.
diff --git a/fs/btrfs/check-integrity.c b/fs/btrfs/check-integrity.c
index 861d472564c1..e34a71b3e225 100644
--- a/fs/btrfs/check-integrity.c
+++ b/fs/btrfs/check-integrity.c
@@ -95,6 +95,7 @@
 #include <linux/genhd.h>
 #include <linux/blkdev.h>
 #include <linux/vmalloc.h>
+#include <linux/string.h>
 #include "ctree.h"
 #include "disk-io.h"
 #include "hash.h"
@@ -105,6 +106,7 @@
 #include "locking.h"
 #include "check-integrity.h"
 #include "rcu-string.h"
+#include "compression.h"
 
 #define BTRFSIC_BLOCK_HASHTABLE_SIZE 0x10000
 #define BTRFSIC_BLOCK_LINK_HASHTABLE_SIZE 0x10000
@@ -176,7 +178,7 @@ struct btrfsic_block {
  * Elements of this type are allocated dynamically and required because
  * each block object can refer to and can be ref from multiple blocks.
  * The key to lookup them in the hashtable is the dev_bytenr of
- * the block ref to plus the one from the block refered from.
+ * the block ref to plus the one from the block referred from.
  * The fact that they are searchable via a hashtable and that a
  * ref_cnt is maintained is not required for the btrfs integrity
  * check algorithm itself, it is only used to make the output more
@@ -3076,7 +3078,7 @@ int btrfsic_mount(struct btrfs_root *root,
 
 	list_for_each_entry(device, dev_head, dev_list) {
 		struct btrfsic_dev_state *ds;
-		char *p;
+		const char *p;
 
 		if (!device->bdev || !device->name)
 			continue;
@@ -3092,11 +3094,7 @@ int btrfsic_mount(struct btrfs_root *root,
 		ds->state = state;
 		bdevname(ds->bdev, ds->name);
 		ds->name[BDEVNAME_SIZE - 1] = '\0';
-		for (p = ds->name; *p != '\0'; p++);
-		while (p > ds->name && *p != '/')
-			p--;
-		if (*p == '/')
-			p++;
+		p = kbasename(ds->name);
 		strlcpy(ds->name, p, sizeof(ds->name));
 		btrfsic_dev_state_hashtable_add(ds,
 						&btrfsic_dev_state_hashtable);
diff --git a/fs/btrfs/compression.h b/fs/btrfs/compression.h
index 13a4dc0436c9..f49d8b8c0f00 100644
--- a/fs/btrfs/compression.h
+++ b/fs/btrfs/compression.h
@@ -48,6 +48,15 @@ int btrfs_submit_compressed_read(struct inode *inode, struct bio *bio,
 void btrfs_clear_biovec_end(struct bio_vec *bvec, int vcnt,
 				   unsigned long pg_index,
 				   unsigned long pg_offset);
+
+enum btrfs_compression_type {
+	BTRFS_COMPRESS_NONE  = 0,
+	BTRFS_COMPRESS_ZLIB  = 1,
+	BTRFS_COMPRESS_LZO   = 2,
+	BTRFS_COMPRESS_TYPES = 2,
+	BTRFS_COMPRESS_LAST  = 3,
+};
+
 struct btrfs_compress_op {
 	struct list_head *(*alloc_workspace)(void);
 
diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index b69ad1305b71..84a6a5b3384a 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -718,14 +718,6 @@ struct btrfs_timespec {
 	__le32 nsec;
 } __attribute__ ((__packed__));
 
-enum btrfs_compression_type {
-	BTRFS_COMPRESS_NONE  = 0,
-	BTRFS_COMPRESS_ZLIB  = 1,
-	BTRFS_COMPRESS_LZO   = 2,
-	BTRFS_COMPRESS_TYPES = 2,
-	BTRFS_COMPRESS_LAST  = 3,
-};
-
 struct btrfs_inode_item {
 	/* nfs style generation number */
 	__le64 generation;
@@ -796,7 +788,7 @@ struct btrfs_root_item {
 
 	/*
 	 * This generation number is used to test if the new fields are valid
-	 * and up to date while reading the root item. Everytime the root item
+	 * and up to date while reading the root item. Every time the root item
 	 * is written out, the "generation" field is copied into this field. If
 	 * anyone ever mounted the fs with an older kernel, we will have
 	 * mismatching generation values here and thus must invalidate the
@@ -1227,10 +1219,10 @@ struct btrfs_space_info {
 	 * we've called update_block_group and dropped the bytes_used counter
 	 * and increased the bytes_pinned counter.  However this means that
 	 * bytes_pinned does not reflect the bytes that will be pinned once the
-	 * delayed refs are flushed, so this counter is inc'ed everytime we call
-	 * btrfs_free_extent so it is a realtime count of what will be freed
-	 * once the transaction is committed.  It will be zero'ed everytime the
-	 * transaction commits.
+	 * delayed refs are flushed, so this counter is inc'ed every time we
+	 * call btrfs_free_extent so it is a realtime count of what will be
+	 * freed once the transaction is committed.  It will be zero'ed every
+	 * time the transaction commits.
 	 */
 	struct percpu_counter total_bytes_pinned;
 
diff --git a/fs/btrfs/delayed-inode.c b/fs/btrfs/delayed-inode.c
index a20d541bb190..6cef0062f929 100644
--- a/fs/btrfs/delayed-inode.c
+++ b/fs/btrfs/delayed-inode.c
@@ -650,9 +650,14 @@ static int btrfs_delayed_inode_reserve_metadata(
 			goto out;
 
 		ret = btrfs_block_rsv_migrate(src_rsv, dst_rsv, num_bytes);
-		if (!WARN_ON(ret))
+		if (!ret)
 			goto out;
 
+		if (btrfs_test_opt(root, ENOSPC_DEBUG)) {
+			btrfs_debug(root->fs_info,
+				    "block rsv migrate returned %d", ret);
+			WARN_ON(1);
+		}
 		/*
 		 * Ok this is a problem, let's just steal from the global rsv
 		 * since this really shouldn't happen that often.
diff --git a/fs/btrfs/dev-replace.c b/fs/btrfs/dev-replace.c
index ff2db7a6c894..a1d6652e0c47 100644
--- a/fs/btrfs/dev-replace.c
+++ b/fs/btrfs/dev-replace.c
@@ -858,7 +858,7 @@ int btrfs_dev_replace_is_ongoing(struct btrfs_dev_replace *dev_replace)
 		 * not called and the the filesystem is remounted
 		 * in degraded state. This does not stop the
 		 * dev_replace procedure. It needs to be canceled
-		 * manually if the cancelation is wanted.
+		 * manually if the cancellation is wanted.
 		 */
 		break;
 	}
diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index 81966676a26b..f6705252b5b2 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -49,6 +49,7 @@
 #include "raid56.h"
 #include "sysfs.h"
 #include "qgroup.h"
+#include "compression.h"
 
 #ifdef CONFIG_X86
 #include <asm/cpufeature.h>
@@ -822,7 +823,7 @@ static void run_one_async_done(struct btrfs_work *work)
 	    waitqueue_active(&fs_info->async_submit_wait))
 		wake_up(&fs_info->async_submit_wait);
 
-	/* If an error occured we just want to clean up the bio and move on */
+	/* If an error occurred we just want to clean up the bio and move on */
 	if (async->error) {
 		async->bio->bi_error = async->error;
 		bio_endio(async->bio);
diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index 083783b53536..53e12977bfd0 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -5758,7 +5758,7 @@ out_fail:
 
 		/*
 		 * This is tricky, but first we need to figure out how much we
-		 * free'd from any free-ers that occured during this
+		 * free'd from any free-ers that occurred during this
 		 * reservation, so we reset ->csum_bytes to the csum_bytes
 		 * before we dropped our lock, and then call the free for the
 		 * number of bytes that were freed while we were trying our
diff --git a/fs/btrfs/extent_map.c b/fs/btrfs/extent_map.c
index cdbadeaef202..318b048eb254 100644
--- a/fs/btrfs/extent_map.c
+++ b/fs/btrfs/extent_map.c
@@ -4,6 +4,7 @@
 #include <linux/hardirq.h>
 #include "ctree.h"
 #include "extent_map.h"
+#include "compression.h"
 
 
 static struct kmem_cache *extent_map_cache;
@@ -61,7 +62,7 @@ struct extent_map *alloc_extent_map(void)
 
 /**
  * free_extent_map - drop reference count of an extent_map
- * @em:		extent map beeing releasead
+ * @em:		extent map being releasead
  *
  * Drops the reference out on @em by one and free the structure
  * if the reference count hits zero.
@@ -421,7 +422,7 @@ struct extent_map *search_extent_mapping(struct extent_map_tree *tree,
 /**
  * remove_extent_mapping - removes an extent_map from the extent tree
  * @tree:	extent tree to remove from
- * @em:		extent map beeing removed
+ * @em:		extent map being removed
  *
  * Removes @em from @tree.  No reference counts are dropped, and no checks
  * are done to see if the range is in use
diff --git a/fs/btrfs/file-item.c b/fs/btrfs/file-item.c
index 1c50a7b09b4e..b5baf5bdc8e1 100644
--- a/fs/btrfs/file-item.c
+++ b/fs/btrfs/file-item.c
@@ -25,6 +25,7 @@
 #include "transaction.h"
 #include "volumes.h"
 #include "print-tree.h"
+#include "compression.h"
 
 #define __MAX_CSUM_ITEMS(r, size) ((unsigned long)(((BTRFS_LEAF_DATA_SIZE(r) - \
 				   sizeof(struct btrfs_item) * 2) / \
@@ -291,12 +292,22 @@ found:
 			page_bytes_left -= root->sectorsize;
 			if (!page_bytes_left) {
 				bio_index++;
+				/*
+				 * make sure we're still inside the
+				 * bio before we update page_bytes_left
+				 */
+				if (bio_index >= bio->bi_vcnt) {
+					WARN_ON_ONCE(count);
+					goto done;
+				}
 				bvec++;
 				page_bytes_left = bvec->bv_len;
 			}
 
 		}
 	}
+
+done:
 	btrfs_free_path(path);
 	return 0;
 }
diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c
index d23d10024cf0..15a09cb156ce 100644
--- a/fs/btrfs/file.c
+++ b/fs/btrfs/file.c
@@ -41,6 +41,7 @@
 #include "locking.h"
 #include "volumes.h"
 #include "qgroup.h"
+#include "compression.h"
 
 static struct kmem_cache *btrfs_inode_defrag_cachep;
 /*
@@ -1846,7 +1847,7 @@ static ssize_t btrfs_file_write_iter(struct kiocb *iocb,
 	/*
 	 * We also have to set last_sub_trans to the current log transid,
 	 * otherwise subsequent syncs to a file that's been synced in this
-	 * transaction will appear to have already occured.
+	 * transaction will appear to have already occurred.
 	 */
 	spin_lock(&BTRFS_I(inode)->lock);
 	BTRFS_I(inode)->last_sub_trans = root->log_transid;
diff --git a/fs/btrfs/inode-map.c b/fs/btrfs/inode-map.c
index e50316c4af15..1f0ec19b23f6 100644
--- a/fs/btrfs/inode-map.c
+++ b/fs/btrfs/inode-map.c
@@ -556,6 +556,9 @@ int btrfs_find_free_objectid(struct btrfs_root *root, u64 *objectid)
 	mutex_lock(&root->objectid_mutex);
 
 	if (unlikely(root->highest_objectid >= BTRFS_LAST_FREE_OBJECTID)) {
+		btrfs_warn(root->fs_info,
+			   "the objectid of root %llu reaches its highest value",
+			   root->root_key.objectid);
 		ret = -ENOSPC;
 		goto out;
 	}
diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index 7a1ffacd314c..053e677839fe 100644
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -60,6 +60,7 @@
 #include "sysfs.h"
 #include "qgroup.h"
 #include "tree-log.h"
+#include "compression.h"
 
 #ifdef CONFIG_64BIT
 /* If we have a 32-bit userspace and 64-bit kernel, then the UAPI
diff --git a/fs/btrfs/ordered-data.c b/fs/btrfs/ordered-data.c
index 988eb1513aa5..0de7da5a610d 100644
--- a/fs/btrfs/ordered-data.c
+++ b/fs/btrfs/ordered-data.c
@@ -25,6 +25,7 @@
 #include "btrfs_inode.h"
 #include "extent_io.h"
 #include "disk-io.h"
+#include "compression.h"
 
 static struct kmem_cache *btrfs_ordered_extent_cache;
 
@@ -1009,7 +1010,7 @@ int btrfs_ordered_update_i_size(struct inode *inode, u64 offset,
 	for (; node; node = rb_prev(node)) {
 		test = rb_entry(node, struct btrfs_ordered_extent, rb_node);
 
-		/* We treat this entry as if it doesnt exist */
+		/* We treat this entry as if it doesn't exist */
 		if (test_bit(BTRFS_ORDERED_UPDATED_ISIZE, &test->flags))
 			continue;
 		if (test->file_offset + test->len <= disk_i_size)
diff --git a/fs/btrfs/props.c b/fs/btrfs/props.c
index f9e60231f685..36992128c746 100644
--- a/fs/btrfs/props.c
+++ b/fs/btrfs/props.c
@@ -22,6 +22,7 @@
 #include "hash.h"
 #include "transaction.h"
 #include "xattr.h"
+#include "compression.h"
 
 #define BTRFS_PROP_HANDLERS_HT_BITS 8
 static DEFINE_HASHTABLE(prop_handlers_ht, BTRFS_PROP_HANDLERS_HT_BITS);
diff --git a/fs/btrfs/scrub.c b/fs/btrfs/scrub.c
index e42aa27c96e9..39dbdcbf4d13 100644
--- a/fs/btrfs/scrub.c
+++ b/fs/btrfs/scrub.c
@@ -611,7 +611,7 @@ static void scrub_print_warning(const char *errstr, struct scrub_block *sblock)
 	u64 flags = 0;
 	u64 ref_root;
 	u32 item_size;
-	u8 ref_level;
+	u8 ref_level = 0;
 	int ret;
 
 	WARN_ON(sblock->page_count < 1);
diff --git a/fs/btrfs/send.c b/fs/btrfs/send.c
index d2e29925f1da..19b7bf4284ee 100644
--- a/fs/btrfs/send.c
+++ b/fs/btrfs/send.c
@@ -34,6 +34,7 @@
 #include "disk-io.h"
 #include "btrfs_inode.h"
 #include "transaction.h"
+#include "compression.h"
 
 static int g_verbose = 0;
 
diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c
index a958f625793b..00b8f37cc306 100644
--- a/fs/btrfs/super.c
+++ b/fs/btrfs/super.c
@@ -2291,7 +2291,7 @@ static void btrfs_interface_exit(void)
 	misc_deregister(&btrfs_misc);
 }
 
-static void btrfs_print_info(void)
+static void btrfs_print_mod_info(void)
 {
 	printk(KERN_INFO "Btrfs loaded"
 #ifdef CONFIG_BTRFS_DEBUG
@@ -2393,7 +2393,7 @@ static int __init init_btrfs_fs(void)
 
 	btrfs_init_lockdep();
 
-	btrfs_print_info();
+	btrfs_print_mod_info();
 
 	err = btrfs_run_sanity_tests();
 	if (err)
diff --git a/fs/btrfs/tests/inode-tests.c b/fs/btrfs/tests/inode-tests.c
index e2d3da02deee..863a6a3af1f8 100644
--- a/fs/btrfs/tests/inode-tests.c
+++ b/fs/btrfs/tests/inode-tests.c
@@ -22,6 +22,7 @@
 #include "../disk-io.h"
 #include "../extent_io.h"
 #include "../volumes.h"
+#include "../compression.h"
 
 static void insert_extent(struct btrfs_root *root, u64 start, u64 len,
 			  u64 ram_bytes, u64 offset, u64 disk_bytenr,
diff --git a/fs/btrfs/tree-log.c b/fs/btrfs/tree-log.c
index 9d2e8ecc5382..24d03c751149 100644
--- a/fs/btrfs/tree-log.c
+++ b/fs/btrfs/tree-log.c
@@ -26,6 +26,7 @@
 #include "print-tree.h"
 #include "backref.h"
 #include "hash.h"
+#include "compression.h"
 
 /* magic values for the inode_only field in btrfs_log_inode:
  *
@@ -1045,7 +1046,7 @@ again:
 
 		/*
 		 * NOTE: we have searched root tree and checked the
-		 * coresponding ref, it does not need to check again.
+		 * corresponding ref, it does not need to check again.
 		 */
 		*search_done = 1;
 	}
diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index 80857b4646c0..e2b54d546b7c 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -2749,7 +2749,7 @@ int btrfs_remove_chunk(struct btrfs_trans_handle *trans,
 	    em->start + em->len < chunk_offset) {
 		/*
 		 * This is a logic error, but we don't want to just rely on the
-		 * user having built with ASSERT enabled, so if ASSERT doens't
+		 * user having built with ASSERT enabled, so if ASSERT doesn't
 		 * do anything we still error out.
 		 */
 		ASSERT(0);
@@ -4119,7 +4119,7 @@ out:
  * Callback for btrfs_uuid_tree_iterate().
  * returns:
  * 0	check succeeded, the entry is not outdated.
- * < 0	if an error occured.
+ * < 0	if an error occurred.
  * > 0	if the check failed, which means the caller shall remove the entry.
  */
 static int btrfs_check_uuid_tree_entry(struct btrfs_fs_info *fs_info,