mi: set correct rc and errno when crc mismatch

[jinliangw]

Before the fix, when we meet crc mismatch response, the errno is 0 and rc is 1. This combination will be mistaken as Admin Generic Command Status code value 0x1 (Invalid Command Opcode):
$ nvme id-ctrl mctp:1,20
crc mismatch
NVMe status: Invalid Command Opcode: A reserved coded value or an unsupported value in the command opcode field(0x1

After the fix, the rc is -1, and errno is set to Bad message.
$ nvme id-ctrl mctp:1,20
crc mismatch
identify controller: Bad message

[igaw]

Looks good. Just wonder if the return right above also needs this treatment?

libnvme/src/nvme/mi.c

Lines 427 to 430 in 5084885

	if (rc) {
	nvme_msg(ep->root, LOG_INFO, "transport failure\n");
	return rc;
	}

[jk-ozlabs]

Looks good to me, thanks!

[jk-ozlabs]

Looks good. Just wonder if the return right above also needs this treatment?

The transport's submit callback should be setting errno appropriately there. The case from this fix is detected entirely from the MI core's MIC check, so we're responsible for setting errno in this case.

[jinliangw]

Thank @igaw and @jk-ozlabs for the review, the checkpatch failure is fixed now.

[igaw]

Thanks!