linux_dsm_epyc7002/include
Paul Mackerras a2932923cc KVM: PPC: Book3S HV: Provide a method for userspace to read and write the HPT
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>
2012-12-06 01:33:57 +01:00
..
acpi Merge branch 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux 2012-10-08 07:14:06 +09:00
asm-generic UAPI: Remove empty non-UAPI Kbuild files 2012-10-17 12:31:15 +01:00
clocksource
crypto Merge branch 'modules-next' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux 2012-10-14 13:39:34 -07:00
drm drm/radeon: add some new SI PCI ids 2012-10-23 10:23:49 -04:00
keys KEYS: Asymmetric key pluggable data parsers 2012-10-08 13:50:13 +10:30
linux KVM: Distangle eventfd code from irqchip 2012-12-06 01:33:49 +01:00
math-emu
media Merge branch 'exynos-drm-next' of git://git.infradead.org/users/kmpark/linux-samsung into drm-next 2012-10-07 21:06:33 +10:00
memory
misc
net Merge branch 'for-john' of git://git.kernel.org/pub/scm/linux/kernel/git/jberg/mac80211 2012-10-17 16:23:33 -04:00
pcmcia
ras
rdma infiniband: pass rdma_cm module to netlink_dump_start 2012-10-07 00:30:56 -04:00
rxrpc
scsi SCSI misc on 20121012 2012-10-13 10:57:01 +09:00
sound Sound updates for 3.7-rc1 2012-10-09 07:07:14 +09:00
target target: Add target_submit_cmd_map_sgls for SGL fabric memory passthrough 2012-10-02 14:16:08 -07:00
trace Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs 2012-10-10 10:49:20 +09:00
uapi KVM: PPC: Book3S HV: Provide a method for userspace to read and write the HPT 2012-12-06 01:33:57 +01:00
video fbdev updates for 3.7 2012-10-12 10:21:02 +09:00
xen Bug-fixes: 2012-10-24 05:17:27 +03:00
Kbuild UAPI: Remove empty non-UAPI Kbuild files 2012-10-17 12:31:15 +01:00