static int nsio_rw_bytes()

in claim.c [252:302]

• 44 lines of code
• 14 McCabe index (conditional complexity)

static int nsio_rw_bytes(struct nd_namespace_common *ndns,
		resource_size_t offset, void *buf, size_t size, int rw,
		unsigned long flags)
{
	struct nd_namespace_io *nsio = to_nd_namespace_io(&ndns->dev);
	unsigned int sz_align = ALIGN(size + (offset & (512 - 1)), 512);
	sector_t sector = offset >> 9;
	int rc = 0, ret = 0;

	if (unlikely(!size))
		return 0;

	if (unlikely(offset + size > nsio->size)) {
		dev_WARN_ONCE(&ndns->dev, 1, "request out of range\n");
		return -EFAULT;
	}

	if (rw == READ) {
		if (unlikely(is_bad_pmem(&nsio->bb, sector, sz_align)))
			return -EIO;
		if (copy_mc_to_kernel(buf, nsio->addr + offset, size) != 0)
			return -EIO;
		return 0;
	}

	if (unlikely(is_bad_pmem(&nsio->bb, sector, sz_align))) {
		if (IS_ALIGNED(offset, 512) && IS_ALIGNED(size, 512)
				&& !(flags & NVDIMM_IO_ATOMIC)) {
			long cleared;

			might_sleep();
			cleared = nvdimm_clear_poison(&ndns->dev,
					nsio->res.start + offset, size);
			if (cleared < size)
				rc = -EIO;
			if (cleared > 0 && cleared / 512) {
				cleared /= 512;
				badblocks_clear(&nsio->bb, sector, cleared);
			}
			arch_invalidate_pmem(nsio->addr + offset, size);
		} else
			rc = -EIO;
	}

	memcpy_flushcache(nsio->addr + offset, buf, size);
	ret = nvdimm_flush(to_nd_region(ndns->dev.parent), NULL);
	if (ret)
		rc = ret;

	return rc;
}