struct bio_map_data *bmd = bio->bi_private;
        int ret = 0;
 
-       if (!bmd || !bmd->is_null_mapped) {
+       if (!bmd->is_null_mapped) {
                /*
                 * if we're in a workqueue, the request is orphaned, so
                 * don't copy into a random user address space, just free
                        break;
        }
 
-       bio_set_flag(bio, BIO_USER_MAPPED);
-
        /*
         * Subtle: if we end up needing to bounce a bio, it would normally
         * disappear when its bi_end_io is run.  However, we need the original
                if (unlikely(bio_flagged(bio, BIO_BOUNCED)))
                        mapped_bio = bio->bi_private;
 
-               if (bio_flagged(mapped_bio, BIO_USER_MAPPED)) {
-                       bio_unmap_user(mapped_bio);
-               } else {
+               if (bio->bi_private) {
                        ret2 = bio_uncopy_user(mapped_bio);
                        if (ret2 && !ret)
                                ret = ret2;
+               } else {
+                       bio_unmap_user(mapped_bio);
                }
 
                mapped_bio = bio;
 
        BIO_NO_PAGE_REF,        /* don't put release vec pages */
        BIO_CLONED,             /* doesn't own data */
        BIO_BOUNCED,            /* bio is a bounce bio */
-       BIO_USER_MAPPED,        /* contains user pages */
        BIO_WORKINGSET,         /* contains userspace workingset pages */
        BIO_QUIET,              /* Make BIO Quiet */
        BIO_CHAIN,              /* chained bio, ->bi_remaining in effect */