zram: return early on error in zram_bvec_rw

When the low-level access fails, don't clear the idle flag or clear the
caches, and just return.

Link: https://lkml.kernel.org/r/20230411171459.567614-7-hch@lst.deSigned-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Minchan Kim <minchan@kernel.org>
Reviewed-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

drivers/block/zram/zram_drv.c

@@ -1933,23 +1933,23 @@ static int zram_bvec_rw(struct zram *zram, struct bio_vec *bvec, u32 index,
 
 	if (!op_is_write(op)) {
 		ret = zram_bvec_read(zram, bvec, index, offset, bio);
+		if (unlikely(ret < 0)) {
+			atomic64_inc(&zram->stats.failed_reads);
+			return ret;
+		}
 		flush_dcache_page(bvec->bv_page);
 	} else {
 		ret = zram_bvec_write(zram, bvec, index, offset, bio);
+		if (unlikely(ret < 0)) {
+			atomic64_inc(&zram->stats.failed_writes);
+			return ret;
+		}
 	}
 
 	zram_slot_lock(zram, index);
 	zram_accessed(zram, index);
 	zram_slot_unlock(zram, index);
-
-	if (unlikely(ret < 0)) {
-		if (!op_is_write(op))
-			atomic64_inc(&zram->stats.failed_reads);
-		else
-			atomic64_inc(&zram->stats.failed_writes);
-	}
-
-	return ret;
+	return 0;
 }
 
 static void __zram_make_request(struct zram *zram, struct bio *bio)