[BIO] request->flags ambiguity

[Samium Gromoff <deepfire@ibe.miee.ru>]

	I might just be completely off base, but something struck me lately as odd, and i`d
	like to hear what you folks think about the issue.

	I`m wondering about the ambiguity of the struct request->flags field.

	Is it ok to have a possibility of a request with conflicting meanings attached to it?
	For example REQ_CMD | REQ_PM_SHUTDOWN | REQ_SPECIAL.

	It may be, depending on the implementation, that they are not completely
	conflicting, but its hard to believe that there is zero ambiguity at all.

	If i`m not mistaken this looks as creating opportunities for various subtle bugs.

	Shouldn`t it make more sense to separate request-type-indicator flags
	into a separate unambiguous type field, which would take
	one of the following values:
		- read/write request
		- sense query
		- power control
		- special request

	And not a currently possible combination of all of them, which seem to be the
	current situation.

-- 
regards, Samium Gromoff