ext4: enforce bigalloc restrictions (e.g., no online resizing, etc.)

At least initially if the bigalloc feature is enabled, we will not
support non-extent mapped inodes, online resizing, online defrag, or
the FITRIM ioctl.  This simplifies the initial implementation.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>

1 files changed, 5 insertions, 0 deletions

diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index 6ecc93979e4..904a9a623da 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -3358,6 +3358,11 @@ int ext4_punch_hole(struct file *file, loff_t offset, loff_t length)
 		return -ENOTSUPP;
 	}
 
+	if (EXT4_SB(inode->i_sb)->s_cluster_ratio > 1) {
+		/* TODO: Add support for bigalloc file systems */
+		return -ENOTSUPP;
+	}
+
 	return ext4_ext_punch_hole(file, offset, length);
 }