1.. SPDX-License-Identifier: GPL-2.0 2 3Large Extended Attribute Values 4------------------------------- 5 6To enable ext4 to store extended attribute values that do not fit in the 7inode or in the single extended attribute block attached to an inode, 8the EA_INODE feature allows us to store the value in the data blocks of 9a regular file inode. This ���EA inode��� is linked only from the extended 10attribute name index and must not appear in a directory entry. The 11inode's i_atime field is used to store a checksum of the xattr value; 12and i_ctime/i_version store a 64-bit reference count, which enables 13sharing of large xattr values between multiple owning inodes. For 14backward compatibility with older versions of this feature, the 15i_mtime/i_generation *may* store a back-reference to the inode number 16and i_generation of the **one** owning inode (in cases where the EA 17inode is not referenced by multiple inodes) to verify that the EA inode 18is the correct one being accessed. 19