892782caf1
This patch adds 2 tcmu attrs to block/unblock a device and reset the ring buffer. They are used when the userspace daemon has crashed or forced to shutdown while IO is executing. On restart, the daemon can block the device so new IO is not sent to userspace while it puts the ring in a clean state. Notes: The reset ring opreation is specific to tcmu, but the block one could be generic. I kept it tcmu specific, because it requires some extra locking/state checks in the main IO path and since other backend modules did not need this functionality I thought only tcmu should take the perf hit. Signed-off-by: Mike Christie <mchristi@redhat.com> Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Linux kernel ============ This file was moved to Documentation/admin-guide/README.rst Please notice that there are several guides for kernel developers and users. These guides can be rendered in a number of formats, like HTML and PDF. In order to build the documentation, use ``make htmldocs`` or ``make pdfdocs``. There are various text files in the Documentation/ subdirectory, several of them using the Restructured Text markup notation. See Documentation/00-INDEX for a list of what is contained in each file. Please read the Documentation/process/changes.rst file, as it contains the requirements for building and running the kernel, and information about the problems which may result by upgrading your kernel.