f2fs: do not support mmap write for large folio

Let's check mmap writes onto the large folio, since we don't support writing
large folios.

Reviewed-by: Daeho Jeong <[email protected]>
Reviewed-by: Chao Yu <[email protected]>
Signed-off-by: Jaegeuk Kim <[email protected]>

Author: Jaegeuk Kim

fs/f2fs/file.c

@@ -82,8 +82,17 @@ static vm_fault_t f2fs_vm_page_mkwrite(struct vm_fault *vmf)
 	int err = 0;
 	vm_fault_t ret;
 
-	if (unlikely(IS_IMMUTABLE(inode)))
+	/*
+	 * We only support large folio on the read case.
+	 * Don't make any dirty pages.
+	 */
+	if (unlikely(IS_IMMUTABLE(inode)) ||
+	    mapping_large_folio_support(inode->i_mapping)) {
+		f2fs_err(sbi, "Not expected: immutable: %d large_folio: %d",
+				IS_IMMUTABLE(inode),
+				mapping_large_folio_support(inode->i_mapping));
 		return VM_FAULT_SIGBUS;
+	}
 
 	if (is_inode_flag_set(inode, FI_COMPRESS_RELEASED)) {
 		err = -EIO;