Merge tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4

Pull ext4 updates from Ted Ts'o:
 "Convert ext4 to use the new mount API, and add support for the
  FS_IOC_GETFSLABEL and FS_IOC_SETFSLABEL ioctls.

  In addition the usual large number of clean ups and bug fixes, in
  particular for the fast_commit feature"

* tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (48 commits)
  ext4: don't use the orphan list when migrating an inode
  ext4: use BUG_ON instead of if condition followed by BUG
  ext4: fix a copy and paste typo
  ext4: set csum seed in tmp inode while migrating to extents
  ext4: remove unnecessary 'offset' assignment
  ext4: remove redundant o_start statement
  ext4: drop an always true check
  ext4: remove unused assignments
  ext4: remove redundant statement
  ext4: remove useless resetting io_end_size in mpage_process_page()
  ext4: allow to change s_last_trim_minblks via sysfs
  ext4: change s_last_trim_minblks type to unsigned long
  ext4: implement support for get/set fs label
  ext4: only set EXT4_MOUNT_QUOTA when journalled quota file is specified
  ext4: don't use kfree() on rcu protected pointer sbi->s_qf_names
  ext4: avoid trim error on fs with small groups
  ext4: fix an use-after-free issue about data=journal writeback mode
  ext4: fix null-ptr-deref in '__ext4_journal_ensure_credits'
  ext4: initialize err_blk before calling __ext4_get_inode_loc
  ext4: fix a possible ABBA deadlock due to busy PA
  ...

fs/ext4/acl.c

@@ -246,7 +246,6 @@ ext4_set_acl(struct user_namespace *mnt_userns, struct inode *inode,
 	handle = ext4_journal_start(inode, EXT4_HT_XATTR, credits);
 	if (IS_ERR(handle))
 		return PTR_ERR(handle);
-	ext4_fc_start_update(inode);
 
 	if ((type == ACL_TYPE_ACCESS) && acl) {
 		error = posix_acl_update_mode(mnt_userns, inode, &mode, &acl);
@@ -264,7 +263,6 @@ ext4_set_acl(struct user_namespace *mnt_userns, struct inode *inode,
 	}
 out_stop:
 	ext4_journal_stop(handle);
-	ext4_fc_stop_update(inode);
 	if (error == -ENOSPC && ext4_should_retry_alloc(inode->i_sb, &retries))
 		goto retry;
 	return error;

fs/ext4/dir.c

@@ -303,7 +303,6 @@ static int ext4_readdir(struct file *file, struct dir_context *ctx)
 			goto done;
 		brelse(bh);
 		bh = NULL;
-		offset = 0;
 	}
 done:
 	err = 0;

fs/ext4/ext4.h

@@ -1298,6 +1298,8 @@ extern void ext4_set_bits(void *bm, int cur, int len);
 /* Metadata checksum algorithm codes */
 #define EXT4_CRC32C_CHKSUM		1
 
+#define EXT4_LABEL_MAX			16
+
 /*
  * Structure of the super block
  */
@@ -1347,7 +1349,7 @@ struct ext4_super_block {
 /*60*/	__le32	s_feature_incompat;	/* incompatible feature set */
 	__le32	s_feature_ro_compat;	/* readonly-compatible feature set */
 /*68*/	__u8	s_uuid[16];		/* 128-bit uuid for volume */
-/*78*/	char	s_volume_name[16];	/* volume name */
+/*78*/	char	s_volume_name[EXT4_LABEL_MAX];	/* volume name */
 /*88*/	char	s_last_mounted[64] __nonstring;	/* directory where last mounted */
 /*C8*/	__le32	s_algorithm_usage_bitmap; /* For compression */
 	/*
@@ -1661,7 +1663,7 @@ struct ext4_sb_info {
 	struct task_struct *s_mmp_tsk;
 
 	/* record the last minlen when FITRIM is called. */
-	atomic_t s_last_trim_minblks;
+	unsigned long s_last_trim_minblks;
 
 	/* Reference to checksum algorithm driver via cryptoapi */
 	struct crypto_shash *s_chksum_driver;
@@ -1725,9 +1727,9 @@ struct ext4_sb_info {
 	 */
 	struct work_struct s_error_work;
 
-	/* Ext4 fast commit stuff */
+	/* Ext4 fast commit sub transaction ID */
 	atomic_t s_fc_subtid;
-	atomic_t s_fc_ineligible_updates;
+
 	/*
 	 * After commit starts, the main queue gets locked, and the further
 	 * updates get added in the staging queue.
@@ -1747,7 +1749,6 @@ struct ext4_sb_info {
 	spinlock_t s_fc_lock;
 	struct buffer_head *s_fc_bh;
 	struct ext4_fc_stats s_fc_stats;
-	u64 s_fc_avg_commit_time;
 #ifdef CONFIG_EXT4_DEBUG
 	int s_fc_debug_max_replay;
 #endif
@@ -2399,8 +2400,7 @@ ext4_rec_len_from_disk(__le16 dlen, unsigned blocksize)
 
 static inline __le16 ext4_rec_len_to_disk(unsigned len, unsigned blocksize)
 {
-	if ((len > blocksize) || (blocksize > (1 << 18)) || (len & 3))
-		BUG();
+	BUG_ON((len > blocksize) || (blocksize > (1 << 18)) || (len & 3));
 #if (PAGE_SIZE >= 65536)
 	if (len < 65536)
 		return cpu_to_le16(len);
@@ -2926,8 +2926,6 @@ void __ext4_fc_track_create(handle_t *handle, struct inode *inode,
 void ext4_fc_track_create(handle_t *handle, struct dentry *dentry);
 void ext4_fc_track_inode(handle_t *handle, struct inode *inode);
 void ext4_fc_mark_ineligible(struct super_block *sb, int reason);
-void ext4_fc_start_ineligible(struct super_block *sb, int reason);
-void ext4_fc_stop_ineligible(struct super_block *sb);
 void ext4_fc_start_update(struct inode *inode);
 void ext4_fc_stop_update(struct inode *inode);
 void ext4_fc_del(struct inode *inode);
@@ -2935,6 +2933,7 @@ bool ext4_fc_replay_check_excluded(struct super_block *sb, ext4_fsblk_t block);
 void ext4_fc_replay_cleanup(struct super_block *sb);
 int ext4_fc_commit(journal_t *journal, tid_t commit_tid);
 int __init ext4_fc_init_dentry_cache(void);
+void ext4_fc_destroy_dentry_cache(void);
 
 /* mballoc.c */
 extern const struct seq_operations ext4_mb_seq_groups_ops;
@@ -3096,6 +3095,9 @@ extern int ext4_group_extend(struct super_block *sb,
 				struct ext4_super_block *es,
 				ext4_fsblk_t n_blocks_count);
 extern int ext4_resize_fs(struct super_block *sb, ext4_fsblk_t n_blocks_count);
+extern unsigned int ext4_list_backups(struct super_block *sb,
+				      unsigned int *three, unsigned int *five,
+				      unsigned int *seven);
 
 /* super.c */
 extern struct buffer_head *ext4_sb_bread(struct super_block *sb,
@@ -3110,6 +3112,8 @@ extern int ext4_read_bh_lock(struct buffer_head *bh, int op_flags, bool wait);
 extern void ext4_sb_breadahead_unmovable(struct super_block *sb, sector_t block);
 extern int ext4_seq_options_show(struct seq_file *seq, void *offset);
 extern int ext4_calculate_overhead(struct super_block *sb);
+extern __le32 ext4_superblock_csum(struct super_block *sb,
+				   struct ext4_super_block *es);
 extern void ext4_superblock_csum_set(struct super_block *sb);
 extern int ext4_alloc_flex_bg_array(struct super_block *sb,
 				    ext4_group_t ngroup);

fs/ext4/ext4_jbd2.c

@@ -162,6 +162,8 @@ int __ext4_journal_ensure_credits(handle_t *handle, int check_cred,
 {
 	if (!ext4_handle_valid(handle))
 		return 0;
+	if (is_handle_aborted(handle))
+		return -EROFS;
 	if (jbd2_handle_buffer_credits(handle) >= check_cred &&
 	    handle->h_revoke_credits >= revoke_cred)
 		return 0;

fs/ext4/extents.c

@@ -1496,8 +1496,7 @@ static int ext4_ext_search_left(struct inode *inode,
 				EXT4_ERROR_INODE(inode,
 				  "ix (%d) != EXT_FIRST_INDEX (%d) (depth %d)!",
 				  ix != NULL ? le32_to_cpu(ix->ei_block) : 0,
-				  EXT_FIRST_INDEX(path[depth].p_hdr) != NULL ?
-		le32_to_cpu(EXT_FIRST_INDEX(path[depth].p_hdr)->ei_block) : 0,
+				  le32_to_cpu(EXT_FIRST_INDEX(path[depth].p_hdr)->ei_block),
 				  depth);
 				return -EFSCORRUPTED;
 			}
@@ -2025,7 +2024,6 @@ int ext4_ext_insert_extent(handle_t *handle, struct inode *inode,
 					+ ext4_ext_get_actual_len(newext));
 			if (unwritten)
 				ext4_ext_mark_unwritten(ex);
-			eh = path[depth].p_hdr;
 			nearex = ex;
 			goto merge;
 		}
@@ -2054,7 +2052,6 @@ int ext4_ext_insert_extent(handle_t *handle, struct inode *inode,
 					+ ext4_ext_get_actual_len(newext));
 			if (unwritten)
 				ext4_ext_mark_unwritten(ex);
-			eh = path[depth].p_hdr;
 			nearex = ex;
 			goto merge;
 		}
@@ -4647,8 +4644,6 @@ static long ext4_zero_range(struct file *file, loff_t offset,
 	ret = ext4_mark_inode_dirty(handle, inode);
 	if (unlikely(ret))
 		goto out_handle;
-	ext4_fc_track_range(handle, inode, offset >> inode->i_sb->s_blocksize_bits,
-			(offset + len - 1) >> inode->i_sb->s_blocksize_bits);
 	/* Zero out partial block at the edges of the range */
 	ret = ext4_zero_partial_blocks(handle, inode, offset, len);
 	if (ret >= 0)
@@ -4697,8 +4692,6 @@ long ext4_fallocate(struct file *file, int mode, loff_t offset, loff_t len)
 		     FALLOC_FL_INSERT_RANGE))
 		return -EOPNOTSUPP;
 
-	ext4_fc_start_update(inode);
-
 	if (mode & FALLOC_FL_PUNCH_HOLE) {
 		ret = ext4_punch_hole(inode, offset, len);
 		goto exit;
@@ -4762,7 +4755,6 @@ long ext4_fallocate(struct file *file, int mode, loff_t offset, loff_t len)
 	inode_unlock(inode);
 	trace_ext4_fallocate_exit(inode, offset, max_blocks, ret);
 exit:
-	ext4_fc_stop_update(inode);
 	return ret;
 }
 
@@ -5344,7 +5336,7 @@ static int ext4_collapse_range(struct inode *inode, loff_t offset, loff_t len)
 		ret = PTR_ERR(handle);
 		goto out_mmap;
 	}
-	ext4_fc_start_ineligible(sb, EXT4_FC_REASON_FALLOC_RANGE);
+	ext4_fc_mark_ineligible(sb, EXT4_FC_REASON_FALLOC_RANGE);
 
 	down_write(&EXT4_I(inode)->i_data_sem);
 	ext4_discard_preallocations(inode, 0);
@@ -5383,7 +5375,6 @@ static int ext4_collapse_range(struct inode *inode, loff_t offset, loff_t len)
 
 out_stop:
 	ext4_journal_stop(handle);
-	ext4_fc_stop_ineligible(sb);
 out_mmap:
 	filemap_invalidate_unlock(mapping);
 out_mutex:
@@ -5485,7 +5476,7 @@ static int ext4_insert_range(struct inode *inode, loff_t offset, loff_t len)
 		ret = PTR_ERR(handle);
 		goto out_mmap;
 	}
-	ext4_fc_start_ineligible(sb, EXT4_FC_REASON_FALLOC_RANGE);
+	ext4_fc_mark_ineligible(sb, EXT4_FC_REASON_FALLOC_RANGE);
 
 	/* Expand file to avoid data loss if there is error while shifting */
 	inode->i_size += len;
@@ -5560,7 +5551,6 @@ static int ext4_insert_range(struct inode *inode, loff_t offset, loff_t len)
 
 out_stop:
 	ext4_journal_stop(handle);
-	ext4_fc_stop_ineligible(sb);
 out_mmap:
 	filemap_invalidate_unlock(mapping);
 out_mutex:

fs/ext4/fast_commit.h

@@ -71,21 +71,19 @@ struct ext4_fc_tail {
 };
 
 /*
- * Fast commit reason codes
+ * Fast commit status codes
  */
 enum {
-	/*
-	 * Commit status codes:
-	 */
-	EXT4_FC_REASON_OK = 0,
-	EXT4_FC_REASON_INELIGIBLE,
-	EXT4_FC_REASON_ALREADY_COMMITTED,
-	EXT4_FC_REASON_FC_START_FAILED,
-	EXT4_FC_REASON_FC_FAILED,
+	EXT4_FC_STATUS_OK = 0,
+	EXT4_FC_STATUS_INELIGIBLE,
+	EXT4_FC_STATUS_SKIPPED,
+	EXT4_FC_STATUS_FAILED,
+};
 
-	/*
+/*
  * Fast commit ineligiblity reasons:
  */
+enum {
 	EXT4_FC_REASON_XATTR = 0,
 	EXT4_FC_REASON_CROSS_RENAME,
 	EXT4_FC_REASON_JOURNAL_FLAG_CHANGE,
@@ -117,7 +115,10 @@ struct ext4_fc_stats {
 	unsigned int fc_ineligible_reason_count[EXT4_FC_REASON_MAX];
 	unsigned long fc_num_commits;
 	unsigned long fc_ineligible_commits;
+	unsigned long fc_failed_commits;
+	unsigned long fc_skipped_commits;
 	unsigned long fc_numblks;
+	u64 s_fc_avg_commit_time;
 };
 
 #define EXT4_FC_REPLAY_REALLOC_INCREMENT	4

fs/ext4/file.c

@@ -259,7 +259,6 @@ static ssize_t ext4_buffered_write_iter(struct kiocb *iocb,
 	if (iocb->ki_flags & IOCB_NOWAIT)
 		return -EOPNOTSUPP;
 
-	ext4_fc_start_update(inode);
 	inode_lock(inode);
 	ret = ext4_write_checks(iocb, from);
 	if (ret <= 0)
@@ -271,7 +270,6 @@ static ssize_t ext4_buffered_write_iter(struct kiocb *iocb,
 
 out:
 	inode_unlock(inode);
-	ext4_fc_stop_update(inode);
 	if (likely(ret > 0)) {
 		iocb->ki_pos += ret;
 		ret = generic_write_sync(iocb, ret);
@@ -552,9 +550,7 @@ static ssize_t ext4_dio_write_iter(struct kiocb *iocb, struct iov_iter *from)
 			goto out;
 		}
 
-		ext4_fc_start_update(inode);
 		ret = ext4_orphan_add(handle, inode);
-		ext4_fc_stop_update(inode);
 		if (ret) {
 			ext4_journal_stop(handle);
 			goto out;

fs/ext4/inode.c

@@ -741,10 +741,11 @@ int ext4_map_blocks(handle_t *handle, struct inode *inode,
 			if (ret)
 				return ret;
 		}
+	}
+	if (retval > 0 && (map->m_flags & EXT4_MAP_UNWRITTEN ||
+				map->m_flags & EXT4_MAP_MAPPED))
 		ext4_fc_track_range(handle, inode, map->m_lblk,
 					map->m_lblk + map->m_len - 1);
-	}
-
 	if (retval < 0)
 		ext_debug(inode, "failed with err %d\n", retval);
 	return retval;
@@ -1844,30 +1845,16 @@ int ext4_da_get_block_prep(struct inode *inode, sector_t iblock,
 	return 0;
 }
 
-static int bget_one(handle_t *handle, struct inode *inode,
-		    struct buffer_head *bh)
-{
-	get_bh(bh);
-	return 0;
-}
-
-static int bput_one(handle_t *handle, struct inode *inode,
-		    struct buffer_head *bh)
-{
-	put_bh(bh);
-	return 0;
-}
-
 static int __ext4_journalled_writepage(struct page *page,
 				       unsigned int len)
 {
 	struct address_space *mapping = page->mapping;
 	struct inode *inode = mapping->host;
-	struct buffer_head *page_bufs = NULL;
 	handle_t *handle = NULL;
 	int ret = 0, err = 0;
 	int inline_data = ext4_has_inline_data(inode);
 	struct buffer_head *inode_bh = NULL;
+	loff_t size;
 
 	ClearPageChecked(page);
 
@@ -1877,14 +1864,6 @@ static int __ext4_journalled_writepage(struct page *page,
 		inode_bh = ext4_journalled_write_inline_data(inode, len, page);
 		if (inode_bh == NULL)
 			goto out;
-	} else {
-		page_bufs = page_buffers(page);
-		if (!page_bufs) {
-			BUG();
-			goto out;
-		}
-		ext4_walk_page_buffers(handle, inode, page_bufs, 0, len,
-				       NULL, bget_one);
 	}
 	/*
 	 * We need to release the page lock before we start the
@@ -1905,7 +1884,8 @@ static int __ext4_journalled_writepage(struct page *page,
 
 	lock_page(page);
 	put_page(page);
-	if (page->mapping != mapping) {
+	size = i_size_read(inode);
+	if (page->mapping != mapping || page_offset(page) > size) {
 		/* The page got truncated from under us */
 		ext4_journal_stop(handle);
 		ret = 0;
@@ -1915,6 +1895,13 @@ static int __ext4_journalled_writepage(struct page *page,
 	if (inline_data) {
 		ret = ext4_mark_inode_dirty(handle, inode);
 	} else {
+		struct buffer_head *page_bufs = page_buffers(page);
+
+		if (page->index == size >> PAGE_SHIFT)
+			len = size & ~PAGE_MASK;
+		else
+			len = PAGE_SIZE;
+
 		ret = ext4_walk_page_buffers(handle, inode, page_bufs, 0, len,
 					     NULL, do_journal_get_write_access);
 
@@ -1935,9 +1922,6 @@ static int __ext4_journalled_writepage(struct page *page,
 out:
 	unlock_page(page);
 out_no_pagelock:
-	if (!inline_data && page_bufs)
-		ext4_walk_page_buffers(NULL, inode, page_bufs, 0, len,
-				       NULL, bput_one);
 	brelse(inode_bh);
 	return ret;
 }
@@ -2257,7 +2241,6 @@ static int mpage_process_page(struct mpage_da_data *mpd, struct page *page,
 			mpd->map.m_len = 0;
 			mpd->map.m_flags = 0;
 			io_end_vec->size += io_end_size;
-			io_end_size = 0;
 
 			err = mpage_process_page_bufs(mpd, head, bh, lblk);
 			if (err > 0)
@@ -2282,7 +2265,6 @@ static int mpage_process_page(struct mpage_da_data *mpd, struct page *page,
 	} while (lblk++, (bh = bh->b_this_page) != head);
 
 	io_end_vec->size += io_end_size;
-	io_end_size = 0;
 	*map_bh = false;
 out:
 	*m_lblk = lblk;
@@ -4523,7 +4505,7 @@ static int __ext4_get_inode_loc(struct super_block *sb, unsigned long ino,
 static int __ext4_get_inode_loc_noinmem(struct inode *inode,
 					struct ext4_iloc *iloc)
 {
-	ext4_fsblk_t err_blk;
+	ext4_fsblk_t err_blk = 0;
 	int ret;
 
 	ret = __ext4_get_inode_loc(inode->i_sb, inode->i_ino, NULL, iloc,
@@ -4538,7 +4520,7 @@ static int __ext4_get_inode_loc_noinmem(struct inode *inode,
 
 int ext4_get_inode_loc(struct inode *inode, struct ext4_iloc *iloc)
 {
-	ext4_fsblk_t err_blk;
+	ext4_fsblk_t err_blk = 0;
 	int ret;
 
 	ret = __ext4_get_inode_loc(inode->i_sb, inode->i_ino, inode, iloc,
@@ -5320,7 +5302,7 @@ int ext4_setattr(struct user_namespace *mnt_userns, struct dentry *dentry,
 		if (error)
 			return error;
 	}
-	ext4_fc_start_update(inode);
+
 	if ((ia_valid & ATTR_UID && !uid_eq(attr->ia_uid, inode->i_uid)) ||
 	    (ia_valid & ATTR_GID && !gid_eq(attr->ia_gid, inode->i_gid))) {
 		handle_t *handle;
@@ -5344,7 +5326,6 @@ int ext4_setattr(struct user_namespace *mnt_userns, struct dentry *dentry,
 
 		if (error) {
 			ext4_journal_stop(handle);
-			ext4_fc_stop_update(inode);
 			return error;
 		}
 		/* Update corresponding info in inode so that everything is in
@@ -5356,7 +5337,6 @@ int ext4_setattr(struct user_namespace *mnt_userns, struct dentry *dentry,
 		error = ext4_mark_inode_dirty(handle, inode);
 		ext4_journal_stop(handle);
 		if (unlikely(error)) {
-			ext4_fc_stop_update(inode);
 			return error;
 		}
 	}
@@ -5370,12 +5350,10 @@ int ext4_setattr(struct user_namespace *mnt_userns, struct dentry *dentry,
 			struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
 
 			if (attr->ia_size > sbi->s_bitmap_maxbytes) {
-				ext4_fc_stop_update(inode);
 				return -EFBIG;
 			}
 		}
 		if (!S_ISREG(inode->i_mode)) {
-			ext4_fc_stop_update(inode);
 			return -EINVAL;
 		}
 
@@ -5427,8 +5405,7 @@ int ext4_setattr(struct user_namespace *mnt_userns, struct dentry *dentry,
 				ext4_fc_track_range(handle, inode,
 					(attr->ia_size > 0 ? attr->ia_size - 1 : 0) >>
 					inode->i_sb->s_blocksize_bits,
-					(oldsize > 0 ? oldsize - 1 : 0) >>
-					inode->i_sb->s_blocksize_bits);
+					EXT_MAX_BLOCKS - 1);
 			else
 				ext4_fc_track_range(
 					handle, inode,
@@ -5499,7 +5476,6 @@ int ext4_setattr(struct user_namespace *mnt_userns, struct dentry *dentry,
 		ext4_std_error(inode->i_sb, error);
 	if (!error)
 		error = rc;
-	ext4_fc_stop_update(inode);
 	return error;
 }
 

fs/ext4/mballoc.c

@@ -4814,7 +4814,7 @@ ext4_mb_release_group_pa(struct ext4_buddy *e4b,
  */
 static noinline_for_stack int
 ext4_mb_discard_group_preallocations(struct super_block *sb,
-					ext4_group_t group, int needed)
+				     ext4_group_t group, int *busy)
 {
 	struct ext4_group_info *grp = ext4_get_group_info(sb, group);
 	struct buffer_head *bitmap_bh = NULL;
@@ -4822,8 +4822,7 @@ ext4_mb_discard_group_preallocations(struct super_block *sb,
 	struct list_head list;
 	struct ext4_buddy e4b;
 	int err;
-	int busy = 0;
-	int free, free_total = 0;
+	int free = 0;
 
 	mb_debug(sb, "discard preallocation for group %u\n", group);
 	if (list_empty(&grp->bb_prealloc_list))
@@ -4846,19 +4845,14 @@ ext4_mb_discard_group_preallocations(struct super_block *sb,
 		goto out_dbg;
 	}
 
-	if (needed == 0)
-		needed = EXT4_CLUSTERS_PER_GROUP(sb) + 1;
-
 	INIT_LIST_HEAD(&list);
-repeat:
-	free = 0;
 	ext4_lock_group(sb, group);
 	list_for_each_entry_safe(pa, tmp,
 				&grp->bb_prealloc_list, pa_group_list) {
 		spin_lock(&pa->pa_lock);
 		if (atomic_read(&pa->pa_count)) {
 			spin_unlock(&pa->pa_lock);
-			busy = 1;
+			*busy = 1;
 			continue;
 		}
 		if (pa->pa_deleted) {
@@ -4898,22 +4892,13 @@ ext4_mb_discard_group_preallocations(struct super_block *sb,
 		call_rcu(&(pa)->u.pa_rcu, ext4_mb_pa_callback);
 	}
 
-	free_total += free;
-
-	/* if we still need more blocks and some PAs were used, try again */
-	if (free_total < needed && busy) {
-		ext4_unlock_group(sb, group);
-		cond_resched();
-		busy = 0;
-		goto repeat;
-	}
 	ext4_unlock_group(sb, group);
 	ext4_mb_unload_buddy(&e4b);
 	put_bh(bitmap_bh);
 out_dbg:
 	mb_debug(sb, "discarded (%d) blocks preallocated for group %u bb_free (%d)\n",
-		 free_total, group, grp->bb_free);
-	return free_total;
+		 free, group, grp->bb_free);
+	return free;
 }
 
 /*
@@ -5455,13 +5440,24 @@ static int ext4_mb_discard_preallocations(struct super_block *sb, int needed)
 {
 	ext4_group_t i, ngroups = ext4_get_groups_count(sb);
 	int ret;
-	int freed = 0;
+	int freed = 0, busy = 0;
+	int retry = 0;
 
 	trace_ext4_mb_discard_preallocations(sb, needed);
+
+	if (needed == 0)
+		needed = EXT4_CLUSTERS_PER_GROUP(sb) + 1;
+ repeat:
 	for (i = 0; i < ngroups && needed > 0; i++) {
-		ret = ext4_mb_discard_group_preallocations(sb, i, needed);
+		ret = ext4_mb_discard_group_preallocations(sb, i, &busy);
 		freed += ret;
 		needed -= ret;
+		cond_resched();
+	}
+
+	if (needed > 0 && busy && ++retry < 3) {
+		busy = 0;
+		goto repeat;
 	}
 
 	return freed;
@@ -6373,7 +6369,7 @@ ext4_trim_all_free(struct super_block *sb, ext4_group_t group,
 	ext4_lock_group(sb, group);
 
 	if (!EXT4_MB_GRP_WAS_TRIMMED(e4b.bd_info) ||
-	    minblocks < atomic_read(&EXT4_SB(sb)->s_last_trim_minblks)) {
+	    minblocks < EXT4_SB(sb)->s_last_trim_minblks) {
 		ret = ext4_try_to_trim_range(sb, &e4b, start, max, minblocks);
 		if (ret >= 0)
 			EXT4_MB_GRP_SET_TRIMMED(e4b.bd_info);
@@ -6404,6 +6400,7 @@ ext4_trim_all_free(struct super_block *sb, ext4_group_t group,
  */
 int ext4_trim_fs(struct super_block *sb, struct fstrim_range *range)
 {
+	struct request_queue *q = bdev_get_queue(sb->s_bdev);
 	struct ext4_group_info *grp;
 	ext4_group_t group, first_group, last_group;
 	ext4_grpblk_t cnt = 0, first_cluster, last_cluster;
@@ -6422,6 +6419,13 @@ int ext4_trim_fs(struct super_block *sb, struct fstrim_range *range)
 	    start >= max_blks ||
 	    range->len < sb->s_blocksize)
 		return -EINVAL;
+	/* No point to try to trim less than discard granularity */
+	if (range->minlen < q->limits.discard_granularity) {
+		minlen = EXT4_NUM_B2C(EXT4_SB(sb),
+			q->limits.discard_granularity >> sb->s_blocksize_bits);
+		if (minlen > EXT4_CLUSTERS_PER_GROUP(sb))
+			goto out;
+	}
 	if (end >= max_blks)
 		end = max_blks - 1;
 	if (end <= first_data_blk)
@@ -6474,7 +6478,7 @@ int ext4_trim_fs(struct super_block *sb, struct fstrim_range *range)
 	}
 
 	if (!ret)
-		atomic_set(&EXT4_SB(sb)->s_last_trim_minblks, minlen);
+		EXT4_SB(sb)->s_last_trim_minblks = minlen;
 
 out:
 	range->len = EXT4_C2B(EXT4_SB(sb), trimmed) << sb->s_blocksize_bits;

fs/ext4/migrate.c

@@ -437,12 +437,12 @@ int ext4_ext_migrate(struct inode *inode)
 	percpu_down_write(&sbi->s_writepages_rwsem);
 
 	/*
-	 * Worst case we can touch the allocation bitmaps, a bgd
-	 * block, and a block to link in the orphan list.  We do need
-	 * need to worry about credits for modifying the quota inode.
+	 * Worst case we can touch the allocation bitmaps and a block
+	 * group descriptor block.  We do need need to worry about
+	 * credits for modifying the quota inode.
 	 */
 	handle = ext4_journal_start(inode, EXT4_HT_MIGRATE,
-		4 + EXT4_MAXQUOTAS_TRANS_BLOCKS(inode->i_sb));
+		3 + EXT4_MAXQUOTAS_TRANS_BLOCKS(inode->i_sb));
 
 	if (IS_ERR(handle)) {
 		retval = PTR_ERR(handle);
@@ -459,6 +459,13 @@ int ext4_ext_migrate(struct inode *inode)
 		ext4_journal_stop(handle);
 		goto out_unlock;
 	}
+	/*
+	 * Use the correct seed for checksum (i.e. the seed from 'inode').  This
+	 * is so that the metadata blocks will have the correct checksum after
+	 * the migration.
+	 */
+	ei = EXT4_I(inode);
+	EXT4_I(tmp_inode)->i_csum_seed = ei->i_csum_seed;
 	i_size_write(tmp_inode, i_size_read(inode));
 	/*
 	 * Set the i_nlink to zero so it will be deleted later
@@ -467,7 +474,6 @@ int ext4_ext_migrate(struct inode *inode)
 	clear_nlink(tmp_inode);
 
 	ext4_ext_tree_init(handle, tmp_inode);
-	ext4_orphan_add(handle, tmp_inode);
 	ext4_journal_stop(handle);
 
 	/*
@@ -492,17 +498,10 @@ int ext4_ext_migrate(struct inode *inode)
 
 	handle = ext4_journal_start(inode, EXT4_HT_MIGRATE, 1);
 	if (IS_ERR(handle)) {
-		/*
-		 * It is impossible to update on-disk structures without
-		 * a handle, so just rollback in-core changes and live other
-		 * work to orphan_list_cleanup()
-		 */
-		ext4_orphan_del(NULL, tmp_inode);
 		retval = PTR_ERR(handle);
 		goto out_tmp_inode;
 	}
 
-	ei = EXT4_I(inode);
 	i_data = ei->i_data;
 	memset(&lb, 0, sizeof(lb));
 

fs/ext4/move_extent.c

@@ -632,7 +632,6 @@ ext4_move_extents(struct file *o_filp, struct file *d_filp, __u64 orig_blk,
 		/* Check hole before the start pos */
 		if (cur_blk + cur_len - 1 < o_start) {
 			if (next_blk == EXT_MAX_BLOCKS) {
-				o_start = o_end;
 				ret = -ENODATA;
 				goto out;
 			}

fs/ext4/resize.c

@@ -717,12 +717,23 @@ static int setup_new_flex_group_blocks(struct super_block *sb,
  * sequence of powers of 3, 5, and 7: 1, 3, 5, 7, 9, 25, 27, 49, 81, ...
  * For a non-sparse filesystem it will be every group: 1, 2, 3, 4, ...
  */
-static unsigned ext4_list_backups(struct super_block *sb, unsigned *three,
-				  unsigned *five, unsigned *seven)
+unsigned int ext4_list_backups(struct super_block *sb, unsigned int *three,
+			       unsigned int *five, unsigned int *seven)
 {
-	unsigned *min = three;
+	struct ext4_super_block *es = EXT4_SB(sb)->s_es;
+	unsigned int *min = three;
 	int mult = 3;
-	unsigned ret;
+	unsigned int ret;
+
+	if (ext4_has_feature_sparse_super2(sb)) {
+		do {
+			if (*min > 2)
+				return UINT_MAX;
+			ret = le32_to_cpu(es->s_backup_bgs[*min - 1]);
+			*min += 1;
+		} while (!ret);
+		return ret;
+	}
 
 	if (!ext4_has_feature_sparse_super(sb)) {
 		ret = *min;

fs/ext4/sysfs.c

@@ -63,7 +63,7 @@ static ssize_t session_write_kbytes_show(struct ext4_sb_info *sbi, char *buf)
 {
 	struct super_block *sb = sbi->s_buddy_cache->i_sb;
 
-	return snprintf(buf, PAGE_SIZE, "%lu\n",
+	return sysfs_emit(buf, "%lu\n",
 			(part_stat_read(sb->s_bdev, sectors[STAT_WRITE]) -
 			 sbi->s_sectors_written_start) >> 1);
 }
@@ -72,7 +72,7 @@ static ssize_t lifetime_write_kbytes_show(struct ext4_sb_info *sbi, char *buf)
 {
 	struct super_block *sb = sbi->s_buddy_cache->i_sb;
 
-	return snprintf(buf, PAGE_SIZE, "%llu\n",
+	return sysfs_emit(buf, "%llu\n",
 			(unsigned long long)(sbi->s_kbytes_written +
 			((part_stat_read(sb->s_bdev, sectors[STAT_WRITE]) -
 			  EXT4_SB(sb)->s_sectors_written_start) >> 1)));
@@ -130,8 +130,8 @@ static ssize_t trigger_test_error(struct ext4_sb_info *sbi,
 static ssize_t journal_task_show(struct ext4_sb_info *sbi, char *buf)
 {
 	if (!sbi->s_journal)
-		return snprintf(buf, PAGE_SIZE, "<none>\n");
-	return snprintf(buf, PAGE_SIZE, "%d\n",
+		return sysfs_emit(buf, "<none>\n");
+	return sysfs_emit(buf, "%d\n",
 			task_pid_vnr(sbi->s_journal->j_task));
 }
 
@@ -245,6 +245,7 @@ EXT4_ATTR(last_error_time, 0444, last_error_time);
 EXT4_ATTR(journal_task, 0444, journal_task);
 EXT4_RW_ATTR_SBI_UI(mb_prefetch, s_mb_prefetch);
 EXT4_RW_ATTR_SBI_UI(mb_prefetch_limit, s_mb_prefetch_limit);
+EXT4_RW_ATTR_SBI_UL(last_trim_minblks, s_last_trim_minblks);
 
 static unsigned int old_bump_val = 128;
 EXT4_ATTR_PTR(max_writeback_mb_bump, 0444, pointer_ui, &old_bump_val);
@@ -295,6 +296,7 @@ static struct attribute *ext4_attrs[] = {
 #endif
 	ATTR_LIST(mb_prefetch),
 	ATTR_LIST(mb_prefetch_limit),
+	ATTR_LIST(last_trim_minblks),
 	NULL,
 };
 ATTRIBUTE_GROUPS(ext4);
@@ -357,7 +359,7 @@ static void *calc_ptr(struct ext4_attr *a, struct ext4_sb_info *sbi)
 
 static ssize_t __print_tstamp(char *buf, __le32 lo, __u8 hi)
 {
-	return snprintf(buf, PAGE_SIZE, "%lld\n",
+	return sysfs_emit(buf, "%lld\n",
 			((time64_t)hi << 32) + le32_to_cpu(lo));
 }
 
@@ -374,7 +376,7 @@ static ssize_t ext4_attr_show(struct kobject *kobj,
 
 	switch (a->attr_id) {
 	case attr_delayed_allocation_blocks:
-		return snprintf(buf, PAGE_SIZE, "%llu\n",
+		return sysfs_emit(buf, "%llu\n",
 				(s64) EXT4_C2B(sbi,
 		       percpu_counter_sum(&sbi->s_dirtyclusters_counter)));
 	case attr_session_write_kbytes:
@@ -382,11 +384,11 @@ static ssize_t ext4_attr_show(struct kobject *kobj,
 	case attr_lifetime_write_kbytes:
 		return lifetime_write_kbytes_show(sbi, buf);
 	case attr_reserved_clusters:
-		return snprintf(buf, PAGE_SIZE, "%llu\n",
+		return sysfs_emit(buf, "%llu\n",
 				(unsigned long long)
 				atomic64_read(&sbi->s_resv_clusters));
 	case attr_sra_exceeded_retry_limit:
-		return snprintf(buf, PAGE_SIZE, "%llu\n",
+		return sysfs_emit(buf, "%llu\n",
 				(unsigned long long)
 			percpu_counter_sum(&sbi->s_sra_exceeded_retry_limit));
 	case attr_inode_readahead:
@@ -394,42 +396,42 @@ static ssize_t ext4_attr_show(struct kobject *kobj,
 		if (!ptr)
 			return 0;
 		if (a->attr_ptr == ptr_ext4_super_block_offset)
-			return snprintf(buf, PAGE_SIZE, "%u\n",
+			return sysfs_emit(buf, "%u\n",
 					le32_to_cpup(ptr));
 		else
-			return snprintf(buf, PAGE_SIZE, "%u\n",
+			return sysfs_emit(buf, "%u\n",
 					*((unsigned int *) ptr));
 	case attr_pointer_ul:
 		if (!ptr)
 			return 0;
-		return snprintf(buf, PAGE_SIZE, "%lu\n",
+		return sysfs_emit(buf, "%lu\n",
 				*((unsigned long *) ptr));
 	case attr_pointer_u8:
 		if (!ptr)
 			return 0;
-		return snprintf(buf, PAGE_SIZE, "%u\n",
+		return sysfs_emit(buf, "%u\n",
 				*((unsigned char *) ptr));
 	case attr_pointer_u64:
 		if (!ptr)
 			return 0;
 		if (a->attr_ptr == ptr_ext4_super_block_offset)
-			return snprintf(buf, PAGE_SIZE, "%llu\n",
+			return sysfs_emit(buf, "%llu\n",
 					le64_to_cpup(ptr));
 		else
-			return snprintf(buf, PAGE_SIZE, "%llu\n",
+			return sysfs_emit(buf, "%llu\n",
 					*((unsigned long long *) ptr));
 	case attr_pointer_string:
 		if (!ptr)
 			return 0;
-		return snprintf(buf, PAGE_SIZE, "%.*s\n", a->attr_size,
+		return sysfs_emit(buf, "%.*s\n", a->attr_size,
 				(char *) ptr);
 	case attr_pointer_atomic:
 		if (!ptr)
 			return 0;
-		return snprintf(buf, PAGE_SIZE, "%d\n",
+		return sysfs_emit(buf, "%d\n",
 				atomic_read((atomic_t *) ptr));
 	case attr_feature:
-		return snprintf(buf, PAGE_SIZE, "supported\n");
+		return sysfs_emit(buf, "supported\n");
 	case attr_first_error_time:
 		return print_tstamp(buf, sbi->s_es, s_first_error_time);
 	case attr_last_error_time:

fs/fs_parser.c

@@ -199,6 +199,8 @@ int fs_param_is_bool(struct p_log *log, const struct fs_parameter_spec *p,
 	int b;
 	if (param->type != fs_value_is_string)
 		return fs_param_bad_value(log, param);
+	if (!*param->string && (p->flags & fs_param_can_be_empty))
+		return 0;
 	b = lookup_constant(bool_names, param->string, -1);
 	if (b == -1)
 		return fs_param_bad_value(log, param);
@@ -211,8 +213,11 @@ int fs_param_is_u32(struct p_log *log, const struct fs_parameter_spec *p,
 		    struct fs_parameter *param, struct fs_parse_result *result)
 {
 	int base = (unsigned long)p->data;
-	if (param->type != fs_value_is_string ||
-	    kstrtouint(param->string, base, &result->uint_32) < 0)
+	if (param->type != fs_value_is_string)
+		return fs_param_bad_value(log, param);
+	if (!*param->string && (p->flags & fs_param_can_be_empty))
+		return 0;
+	if (kstrtouint(param->string, base, &result->uint_32) < 0)
 		return fs_param_bad_value(log, param);
 	return 0;
 }
@@ -221,8 +226,11 @@ EXPORT_SYMBOL(fs_param_is_u32);
 int fs_param_is_s32(struct p_log *log, const struct fs_parameter_spec *p,
 		    struct fs_parameter *param, struct fs_parse_result *result)
 {
-	if (param->type != fs_value_is_string ||
-	    kstrtoint(param->string, 0, &result->int_32) < 0)
+	if (param->type != fs_value_is_string)
+		return fs_param_bad_value(log, param);
+	if (!*param->string && (p->flags & fs_param_can_be_empty))
+		return 0;
+	if (kstrtoint(param->string, 0, &result->int_32) < 0)
 		return fs_param_bad_value(log, param);
 	return 0;
 }
@@ -231,8 +239,11 @@ EXPORT_SYMBOL(fs_param_is_s32);
 int fs_param_is_u64(struct p_log *log, const struct fs_parameter_spec *p,
 		    struct fs_parameter *param, struct fs_parse_result *result)
 {
-	if (param->type != fs_value_is_string ||
-	    kstrtoull(param->string, 0, &result->uint_64) < 0)
+	if (param->type != fs_value_is_string)
+		return fs_param_bad_value(log, param);
+	if (!*param->string && (p->flags & fs_param_can_be_empty))
+		return 0;
+	if (kstrtoull(param->string, 0, &result->uint_64) < 0)
 		return fs_param_bad_value(log, param);
 	return 0;
 }
@@ -244,6 +255,8 @@ int fs_param_is_enum(struct p_log *log, const struct fs_parameter_spec *p,
 	const struct constant_table *c;
 	if (param->type != fs_value_is_string)
 		return fs_param_bad_value(log, param);
+	if (!*param->string && (p->flags & fs_param_can_be_empty))
+		return 0;
 	c = __lookup_constant(p->data, param->string);
 	if (!c)
 		return fs_param_bad_value(log, param);
@@ -255,7 +268,8 @@ EXPORT_SYMBOL(fs_param_is_enum);
 int fs_param_is_string(struct p_log *log, const struct fs_parameter_spec *p,
 		       struct fs_parameter *param, struct fs_parse_result *result)
 {
-	if (param->type != fs_value_is_string || !*param->string)
+	if (param->type != fs_value_is_string ||
+	    (!*param->string && !(p->flags & fs_param_can_be_empty)))
 		return fs_param_bad_value(log, param);
 	return 0;
 }
@@ -275,7 +289,8 @@ int fs_param_is_fd(struct p_log *log, const struct fs_parameter_spec *p,
 {
 	switch (param->type) {
 	case fs_value_is_string:
-		if (kstrtouint(param->string, 0, &result->uint_32) < 0)
+		if ((!*param->string && !(p->flags & fs_param_can_be_empty)) ||
+		    kstrtouint(param->string, 0, &result->uint_32) < 0)
 			break;
 		if (result->uint_32 <= INT_MAX)
 			return 0;

fs/jbd2/journal.c

@@ -757,6 +757,7 @@ int jbd2_fc_begin_commit(journal_t *journal, tid_t tid)
 	}
 	journal->j_flags |= JBD2_FAST_COMMIT_ONGOING;
 	write_unlock(&journal->j_state_lock);
+	jbd2_journal_lock_updates(journal);
 
 	return 0;
 }
@@ -768,6 +769,7 @@ EXPORT_SYMBOL(jbd2_fc_begin_commit);
  */
 static int __jbd2_fc_end_commit(journal_t *journal, tid_t tid, bool fallback)
 {
+	jbd2_journal_unlock_updates(journal);
 	if (journal->j_fc_cleanup_callback)
 		journal->j_fc_cleanup_callback(journal, 0);
 	write_lock(&journal->j_state_lock);

include/linux/fs_parser.h

@@ -42,7 +42,7 @@ struct fs_parameter_spec {
 	u8			opt;	/* Option number (returned by fs_parse()) */
 	unsigned short		flags;
 #define fs_param_neg_with_no	0x0002	/* "noxxx" is negative param */
-#define fs_param_neg_with_empty	0x0004	/* "xxx=" is negative param */
+#define fs_param_can_be_empty	0x0004	/* "xxx=" is allowed */
 #define fs_param_deprecated	0x0008	/* The param is deprecated */
 	const void		*data;
 };

include/trace/events/ext4.h

@@ -2837,6 +2837,29 @@ TRACE_EVENT(ext4_fc_track_range,
 		      __entry->end)
 	);
 
+TRACE_EVENT(ext4_update_sb,
+	TP_PROTO(struct super_block *sb, ext4_fsblk_t fsblk,
+		 unsigned int flags),
+
+	TP_ARGS(sb, fsblk, flags),
+
+	TP_STRUCT__entry(
+		__field(dev_t,		dev)
+		__field(ext4_fsblk_t,	fsblk)
+		__field(unsigned int,	flags)
+	),
+
+	TP_fast_assign(
+		__entry->dev	= sb->s_dev;
+		__entry->fsblk	= fsblk;
+		__entry->flags	= flags;
+	),
+
+	TP_printk("dev %d,%d fsblk %llu flags %u",
+		  MAJOR(__entry->dev), MINOR(__entry->dev),
+		  __entry->fsblk, __entry->flags)
+);
+
 #endif /* _TRACE_EXT4_H */
 
 /* This part must be outside protection */