f2fs: move verity info pointer to fs-specific part of inode

Move the fsverity_info pointer into the filesystem-specific part of the
inode by adding the field f2fs_inode_info::i_verity_info and configuring
fsverity_operations::inode_info_offs accordingly.

This is a prerequisite for a later commit that removes
inode::i_verity_info, saving memory and improving cache efficiency on
filesystems that don't support fsverity.

Co-developed-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Eric Biggers <ebiggers@kernel.org>
Link: https://lore.kernel.org/20250810075706.172910-11-ebiggers@kernel.org
Signed-off-by: Christian Brauner <brauner@kernel.org>

Author: Eric Biggers

fs/f2fs/f2fs.h

@@ -910,6 +910,9 @@ struct f2fs_inode_info {
 #ifdef CONFIG_FS_ENCRYPTION
 	struct fscrypt_inode_info *i_crypt_info; /* filesystem encryption info */
 #endif
+#ifdef CONFIG_FS_VERITY
+	struct fsverity_info *i_verity_info; /* filesystem verity info */
+#endif
 };
 
 static inline void get_read_extent_info(struct extent_info *ext,

fs/f2fs/super.c

@@ -483,6 +483,9 @@ static void init_once(void *foo)
 #ifdef CONFIG_FS_ENCRYPTION
 	fi->i_crypt_info = NULL;
 #endif
+#ifdef CONFIG_FS_VERITY
+	fi->i_verity_info = NULL;
+#endif
 }
 
 #ifdef CONFIG_QUOTA

fs/f2fs/verity.c

@@ -287,6 +287,8 @@ static int f2fs_write_merkle_tree_block(struct inode *inode, const void *buf,
 }
 
 const struct fsverity_operations f2fs_verityops = {
+	.inode_info_offs	= (int)offsetof(struct f2fs_inode_info, i_verity_info) -
+				  (int)offsetof(struct f2fs_inode_info, vfs_inode),
 	.begin_enable_verity	= f2fs_begin_enable_verity,
 	.end_enable_verity	= f2fs_end_enable_verity,
 	.get_verity_descriptor	= f2fs_get_verity_descriptor,