If userspace wants to change some specific bits of TSR
(timer status register) then it uses GET/SET_SREGS ioctl interface.
So the steps will be:
i) user-space will make get ioctl,
ii) change TSR in userspace
iii) then make set ioctl.
It can happen that TSR gets changed by kernel after step i) and
before step iii).
To avoid this we have added below one_reg ioctls for oring and clearing
specific bits in TSR. This patch adds one registerface for:
1) setting specific bit in TSR (timer status register)
2) clearing specific bit in TSR (timer status register)
3) setting/getting the TCR register. There are cases where we want to only
change TCR and not TSR. Although we can uses SREGS without
KVM_SREGS_E_UPDATE_TSR flag but I think one reg is better. I am open
if someone feels we should use SREGS only here.
4) getting/setting TSR register
Signed-off-by: Bharat Bhushan <bharat.bhushan@freescale.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
We need to be able to read and write the contents of the EPR register
from user space.
This patch implements that logic through the ONE_REG API and declares
its (never implemented) SREGS counterpart as deprecated.
Signed-off-by: Alexander Graf <agraf@suse.de>
Implement ONE_REG interface for EPCR register adding KVM_REG_PPC_EPCR to
the list of ONE_REG PPC supported registers.
Signed-off-by: Mihai Caraman <mihai.caraman@freescale.com>
[agraf: remove HV dependency, use get/put_user]
Signed-off-by: Alexander Graf <agraf@suse.de>
A new ioctl, KVM_PPC_GET_HTAB_FD, returns a file descriptor. Reads on
this fd return the contents of the HPT (hashed page table), writes
create and/or remove entries in the HPT. There is a new capability,
KVM_CAP_PPC_HTAB_FD, to indicate the presence of the ioctl. The ioctl
takes an argument structure with the index of the first HPT entry to
read out and a set of flags. The flags indicate whether the user is
intending to read or write the HPT, and whether to return all entries
or only the "bolted" entries (those with the bolted bit, 0x10, set in
the first doubleword).
This is intended for use in implementing qemu's savevm/loadvm and for
live migration. Therefore, on reads, the first pass returns information
about all HPTEs (or all bolted HPTEs). When the first pass reaches the
end of the HPT, it returns from the read. Subsequent reads only return
information about HPTEs that have changed since they were last read.
A read that finds no changed HPTEs in the HPT following where the last
read finished will return 0 bytes.
The format of the data provides a simple run-length compression of the
invalid entries. Each block of data starts with a header that indicates
the index (position in the HPT, which is just an array), the number of
valid entries starting at that index (may be zero), and the number of
invalid entries following those valid entries. The valid entries, 16
bytes each, follow the header. The invalid entries are not explicitly
represented.
Signed-off-by: Paul Mackerras <paulus@samba.org>
[agraf: fix documentation]
Signed-off-by: Alexander Graf <agraf@suse.de>
Merge reason: development work has dependency on kvm patches merged
upstream.
Conflicts:
arch/powerpc/include/asm/Kbuild
arch/powerpc/include/asm/kvm_para.h
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Michael Kerrisk <mtk.manpages@gmail.com>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: Dave Jones <davej@redhat.com>
Bharat Bhushan