Update Linux to v5.4.2
Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/fs/xfs/xfs_bio_io.c b/fs/xfs/xfs_bio_io.c
new file mode 100644
index 0000000..e2148f2
--- /dev/null
+++ b/fs/xfs/xfs_bio_io.c
@@ -0,0 +1,61 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2019 Christoph Hellwig.
+ */
+#include "xfs.h"
+
+static inline unsigned int bio_max_vecs(unsigned int count)
+{
+ return min_t(unsigned, howmany(count, PAGE_SIZE), BIO_MAX_PAGES);
+}
+
+int
+xfs_rw_bdev(
+ struct block_device *bdev,
+ sector_t sector,
+ unsigned int count,
+ char *data,
+ unsigned int op)
+
+{
+ unsigned int is_vmalloc = is_vmalloc_addr(data);
+ unsigned int left = count;
+ int error;
+ struct bio *bio;
+
+ if (is_vmalloc && op == REQ_OP_WRITE)
+ flush_kernel_vmap_range(data, count);
+
+ bio = bio_alloc(GFP_KERNEL, bio_max_vecs(left));
+ bio_set_dev(bio, bdev);
+ bio->bi_iter.bi_sector = sector;
+ bio->bi_opf = op | REQ_META | REQ_SYNC;
+
+ do {
+ struct page *page = kmem_to_page(data);
+ unsigned int off = offset_in_page(data);
+ unsigned int len = min_t(unsigned, left, PAGE_SIZE - off);
+
+ while (bio_add_page(bio, page, len, off) != len) {
+ struct bio *prev = bio;
+
+ bio = bio_alloc(GFP_KERNEL, bio_max_vecs(left));
+ bio_copy_dev(bio, prev);
+ bio->bi_iter.bi_sector = bio_end_sector(prev);
+ bio->bi_opf = prev->bi_opf;
+ bio_chain(prev, bio);
+
+ submit_bio(prev);
+ }
+
+ data += len;
+ left -= len;
+ } while (left > 0);
+
+ error = submit_bio_wait(bio);
+ bio_put(bio);
+
+ if (is_vmalloc && op == REQ_OP_READ)
+ invalidate_kernel_vmap_range(data, count);
+ return error;
+}