Skip to content

K
Kernel

openeuler / Kernel
1 年多 前同步成功

通知 8
Star 0
Fork 0
K
Kernel
切换分支/标签
  1. 17 10月, 2013 5 次提交
    • A
      kvm: powerpc: Add kvmppc_ops callback · 3a167bea
      由 Aneesh Kumar K.V 提交于 
      This patch add a new callback kvmppc_ops. This will help us in enabling
both HV and PR KVM together in the same kernel. The actual change to
enable them together is done in the later patch in the series.
Signed-off-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
[agraf: squash in booke changes]
Signed-off-by: NAlexander Graf <agraf@suse.de>
      3a167bea
    • P
      KVM: PPC: Book3S PR: Mark pages accessed, and dirty if being written · adc0bafe
      由 Paul Mackerras 提交于 
      The mark_page_dirty() function, despite what its name might suggest,
doesn't actually mark the page as dirty as far as the MM subsystem is
concerned.  It merely sets a bit in KVM's map of dirty pages, if
userspace has requested dirty tracking for the relevant memslot.
To tell the MM subsystem that the page is dirty, we have to call
kvm_set_pfn_dirty() (or an equivalent such as SetPageDirty()).

This adds a call to kvm_set_pfn_dirty(), and while we are here, also
adds a call to kvm_set_pfn_accessed() to tell the MM subsystem that
the page has been accessed.  Since we are now using the pfn in
several places, this adds a 'pfn' variable to store it and changes
the places that used hpaddr >> PAGE_SHIFT to use pfn instead, which
is the same thing.

This also changes a use of HPTE_R_PP to PP_RXRX.  Both are 3, but
PP_RXRX is more informative as being the read-only page permission
bit setting.
Signed-off-by: NPaul Mackerras <paulus@samba.org>
Signed-off-by: NAlexander Graf <agraf@suse.de>
      adc0bafe
    • P
      KVM: PPC: Book3S PR: Use mmu_notifier_retry() in kvmppc_mmu_map_page() · d78bca72
      由 Paul Mackerras 提交于 
      When the MM code is invalidating a range of pages, it calls the KVM
kvm_mmu_notifier_invalidate_range_start() notifier function, which calls
kvm_unmap_hva_range(), which arranges to flush all the existing host
HPTEs for guest pages.  However, the Linux PTEs for the range being
flushed are still valid at that point.  We are not supposed to establish
any new references to pages in the range until the ...range_end()
notifier gets called.  The PPC-specific KVM code doesn't get any
explicit notification of that; instead, we are supposed to use
mmu_notifier_retry() to test whether we are or have been inside a
range flush notifier pair while we have been getting a page and
instantiating a host HPTE for the page.

This therefore adds a call to mmu_notifier_retry inside
kvmppc_mmu_map_page().  This call is inside a region locked with
kvm->mmu_lock, which is the same lock that is called by the KVM
MMU notifier functions, thus ensuring that no new notification can
proceed while we are in the locked region.  Inside this region we
also create the host HPTE and link the corresponding hpte_cache
structure into the lists used to find it later.  We cannot allocate
the hpte_cache structure inside this locked region because that can
lead to deadlock, so we allocate it outside the region and free it
if we end up not using it.

This also moves the updates of vcpu3s->hpte_cache_count inside the
regions locked with vcpu3s->mmu_lock, and does the increment in
kvmppc_mmu_hpte_cache_map() when the pte is added to the cache
rather than when it is allocated, in order that the hpte_cache_count
is accurate.
Signed-off-by: NPaul Mackerras <paulus@samba.org>
Signed-off-by: NAlexander Graf <agraf@suse.de>
      d78bca72
    • P
      KVM: PPC: Book3S PR: Better handling of host-side read-only pages · 93b159b4
      由 Paul Mackerras 提交于 
      Currently we request write access to all pages that get mapped into the
guest, even if the guest is only loading from the page.  This reduces
the effectiveness of KSM because it means that we unshare every page we
access.  Also, we always set the changed (C) bit in the guest HPTE if
it allows writing, even for a guest load.

This fixes both these problems.  We pass an 'iswrite' flag to the
mmu.xlate() functions and to kvmppc_mmu_map_page() to indicate whether
the access is a load or a store.  The mmu.xlate() functions now only
set C for stores.  kvmppc_gfn_to_pfn() now calls gfn_to_pfn_prot()
instead of gfn_to_pfn() so that it can indicate whether we need write
access to the page, and get back a 'writable' flag to indicate whether
the page is writable or not.  If that 'writable' flag is clear, we then
make the host HPTE read-only even if the guest HPTE allowed writing.

This means that we can get a protection fault when the guest writes to a
page that it has mapped read-write but which is read-only on the host
side (perhaps due to KSM having merged the page).  Thus we now call
kvmppc_handle_pagefault() for protection faults as well as HPTE not found
faults.  In kvmppc_handle_pagefault(), if the access was allowed by the
guest HPTE and we thus need to install a new host HPTE, we then need to
remove the old host HPTE if there is one.  This is done with a new
function, kvmppc_mmu_unmap_page(), which uses kvmppc_mmu_pte_vflush() to
find and remove the old host HPTE.

Since the memslot-related functions require the KVM SRCU read lock to
be held, this adds srcu_read_lock/unlock pairs around the calls to
kvmppc_handle_pagefault().

Finally, this changes kvmppc_mmu_book3s_32_xlate_pte() to not ignore
guest HPTEs that don't permit access, and to return -EPERM for accesses
that are not permitted by the page protections.
Signed-off-by: NPaul Mackerras <paulus@samba.org>
Signed-off-by: NAlexander Graf <agraf@suse.de>
      93b159b4
    • P
      KVM: PPC: Book3S PR: Use 64k host pages where possible · c9029c34
      由 Paul Mackerras 提交于 
      Currently, PR KVM uses 4k pages for the host-side mappings of guest
memory, regardless of the host page size.  When the host page size is
64kB, we might as well use 64k host page mappings for guest mappings
of 64kB and larger pages and for guest real-mode mappings.  However,
the magic page has to remain a 4k page.

To implement this, we first add another flag bit to the guest VSID
values we use, to indicate that this segment is one where host pages
should be mapped using 64k pages.  For segments with this bit set
we set the bits in the shadow SLB entry to indicate a 64k base page
size.  When faulting in host HPTEs for this segment, we make them
64k HPTEs instead of 4k.  We record the pagesize in struct hpte_cache
for use when invalidating the HPTE.

For now we restrict the segment containing the magic page (if any) to
4k pages.  It should be possible to lift this restriction in future
by ensuring that the magic 4k page is appropriately positioned within
a host 64k page.
Signed-off-by: NPaul Mackerras <paulus@samba.org>
Signed-off-by: NAlexander Graf <agraf@suse.de>
      c9029c34
  3. 30 6月, 2013 2 次提交
    • P
      KVM: PPC: Book3S PR: Allow guest to use 1TB segments · 0f296829
      由 Paul Mackerras 提交于 
      With this, the guest can use 1TB segments as well as 256MB segments.
Since we now have the situation where a single emulated guest segment
could correspond to multiple shadow segments (as the shadow segments
are still 256MB segments), this adds a new kvmppc_mmu_flush_segment()
to scan for all shadow segments that need to be removed.

This restructures the guest HPT (hashed page table) lookup code to
use the correct hashing and matching functions for HPTEs within a
1TB segment.  We use the standard hpt_hash() function instead of
open-coding the hash calculation, and we use HPTE_V_COMPARE() with
an AVPN value that has the B (segment size) field included.  The
calculation of avpn is done a little earlier since it doesn't change
in the loop starting at the do_second label.

The computation in kvmppc_mmu_book3s_64_esid_to_vsid() changes so that
it returns a 256MB VSID even if the guest SLB entry is a 1TB entry.
This is because the users of this function are creating 256MB SLB
entries.  We set a new VSID_1T flag so that entries created from 1T
segments don't collide with entries from 256MB segments.
Signed-off-by: NPaul Mackerras <paulus@samba.org>
Signed-off-by: NAlexander Graf <agraf@suse.de>
      0f296829
    • P
      KVM: PPC: Book3S PR: Fix proto-VSID calculations · 8ed7b7e9
      由 Paul Mackerras 提交于 
      This makes sure the calculation of the proto-VSIDs used by PR KVM
is done with 64-bit arithmetic.  Since vcpu3s->context_id[] is int,
when we do vcpu3s->context_id[0] << ESID_BITS the shift will be done
with 32-bit instructions, possibly leading to significant bits
getting lost, as the context id can be up to 524283 and ESID_BITS is
18.  To fix this we cast the context id to u64 before shifting.
Signed-off-by: NPaul Mackerras <paulus@samba.org>
Signed-off-by: NAlexander Graf <agraf@suse.de>
      8ed7b7e9
  5. 21 6月, 2013 1 次提交
  7. 30 4月, 2013 1 次提交
  9. 17 3月, 2013 1 次提交
  11. 30 10月, 2012 1 次提交
  13. 06 10月, 2012 1 次提交
  15. 17 9月, 2012 1 次提交
  17. 16 8月, 2012 1 次提交
  19. 16 5月, 2012 1 次提交
  21. 05 3月, 2012 1 次提交
  23. 24 10月, 2010 9 次提交
  25. 01 8月, 2010 3 次提交
  27. 17 5月, 2010 7 次提交
  29. 25 4月, 2010 1 次提交
    • A
      KVM: PPC: Enable use of secondary htab bucket · 20a340ab
      由 Alexander Graf 提交于 
      We had code to make use of the secondary htab buckets, but kept that
disabled because it was unstable when I put it in.

I checked again if that's still the case and apparently it was only
exposing some instability that was there anyways before. I haven't
seen any badness related to usage of secondary htab entries so far.

This should speed up guest memory allocations by quite a bit, because
we now have more space to put PTEs in.
Signed-off-by: NAlexander Graf <agraf@suse.de>
Signed-off-by: NAvi Kivity <avi@redhat.com>
      20a340ab
  31. 05 11月, 2009 1 次提交
    • A
      Add book3s_64 Host MMU handling · 0d8dc681
      由 Alexander Graf 提交于 
      We designed the Book3S port of KVM as modular as possible. Most
of the code could be easily used on a Book3S_32 host as well.

The main difference between 32 and 64 bit cores is the MMU. To keep
things well separated, we treat the book3s_64 MMU as one possible compile
option.

This patch adds all the MMU helpers the rest of the code needs in
order to modify the host's MMU, like setting PTEs and segments.
Signed-off-by: NAlexander Graf <agraf@suse.de>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
      0d8dc681