don't rely upon subsequent bio_add_pc_page() calls failing (e2e115d1) · Commits · 戴 / test

... they might actually succeed in some cases (when we are at the queue-imposed segments limit, the next page is not mergable with the last one we'd got in, but the first page covered by the next iovec *is* mergable). Make sure that once it's failed, we are done with that bio. Signed-off-by:

Al Viro <viro@zeniv.linux.org.uk>

block/bio.c

+4 −4

Original line number	Diff line number	Diff line
		@@ -1380,10 +1380,7 @@ struct bio bio_map_user_iov(struct request_queue q,
		if (n > bytes)
		n = bytes;

		/*
		* sorry...
		*/
		if (bio_add_pc_page(q, bio, pages[j], n, offs) < n)
		if (!bio_add_pc_page(q, bio, pages[j], n, offs))
		break;

		/*
		@@ -1405,6 +1402,9 @@ struct bio bio_map_user_iov(struct request_queue q,
		while (j < npages)
		put_page(pages[j++]);
		kvfree(pages);
		/* couldn't stuff something into bio? */
		if (bytes)
		break;
		}

		bio_set_flag(bio, BIO_USER_MAPPED);

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