0c05e10bce
Make emulator_pio_in_out operate directly on the provided buffer as long as PIO is handled inside KVM. For input operations, this means that, in the case of in-kernel PIO, __emulator_pio_in() does not have to be always followed by complete_emulator_pio_in(). This affects emulator_pio_in() and kvm_sev_es_ins(); for the latter, that is why the call moves from advance_sev_es_emulated_ins() to complete_sev_es_emulated_ins(). For output, it means that vcpu->pio.count is never set unnecessarily and there is no need to clear it; but also vcpu->pio.size must not be used in kvm_sev_es_outs(), because it will not be updated for in-kernel OUT. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
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.