This makes the separation between the sanity checks and the rest of the
code a bit clearer.
Reviewed-by: NMarcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: NTakuya Yoshikawa <yoshikawa_takuya_b1@lab.ntt.co.jp>
Signed-off-by: NGleb Natapov <gleb@redhat.com>

Calling kvm_mmu_slot_remove_write_access() for a deleted slot does
nothing but search for non-existent mmu pages which have mappings to
that deleted memory; this is safe but a waste of time.

Since we want to make the function rmap based in a later patch, in a
manner which makes it unsafe to be called for a deleted slot, we makes
the caller see if the slot is non-zero and being dirty logged.
Reviewed-by: NMarcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: NTakuya Yoshikawa <yoshikawa_takuya_b1@lab.ntt.co.jp>
Signed-off-by: NGleb Natapov <gleb@redhat.com>

Move repetitive code sequence to a separate function.
Reviewed-by: NAlex Williamson <alex.williamson@redhat.com>
Signed-off-by: NGleb Natapov <gleb@redhat.com>

Previous patch "kvm: Minor memory slot optimization" (b7f69c55)
overlooked the generation field of the memory slots.  Re-using the
original memory slots left us with with two slightly different memory
slots with the same generation.  To fix this, make update_memslots()
take a new parameter to specify the last generation.  This also makes
generation management more explicit to avoid such problems in the future.
Reported-by: NTakuya Yoshikawa <yoshikawa_takuya_b1@lab.ntt.co.jp>
Signed-off-by: NAlex Williamson <alex.williamson@redhat.com>
Signed-off-by: NGleb Natapov <gleb@redhat.com>

This hack is wrong. The pin number of PIT is connected to
2 not 0. This means this hack never takes effect. So it is ok
to remove it.
Signed-off-by: NYang Zhang <yang.z.zhang@Intel.com>
Signed-off-by: NGleb Natapov <gleb@redhat.com>

We're currently offering a whopping 32 memory slots to user space, an
int is a bit excessive for storing this.  We would like to increase
our memslots, but SHRT_MAX should be more than enough.
Reviewed-by: NGleb Natapov <gleb@redhat.com>
Signed-off-by: NAlex Williamson <alex.williamson@redhat.com>
Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>

There's no need for this to be an int, it holds a boolean.
Move to the end of the struct for alignment.
Reviewed-by: NGleb Natapov <gleb@redhat.com>
Signed-off-by: NAlex Williamson <alex.williamson@redhat.com>
Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>

It's easy to confuse KVM_MEMORY_SLOTS and KVM_MEM_SLOTS_NUM.  One is
the user accessible slots and the other is user + private.  Make this
more obvious.
Reviewed-by: NGleb Natapov <gleb@redhat.com>
Signed-off-by: NAlex Williamson <alex.williamson@redhat.com>
Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>

If a slot is removed or moved in the guest physical address space, we
first allocate and install a new slot array with the invalidated
entry.  The old array is then freed.  We then proceed to allocate yet
another slot array to install the permanent replacement.  Re-use the
original array when this occurs and avoid the extra kfree/kmalloc.
Reviewed-by: NGleb Natapov <gleb@redhat.com>
Signed-off-by: NAlex Williamson <alex.williamson@redhat.com>
Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>

The iommu integration into memory slots expects memory slots to be
added or removed and doesn't handle the move case.  We can unmap
slots from the iommu after we mark them invalid and map them before
installing the final memslot array.  Also re-order the kmemdup vs
map so we don't leave iommu mappings if we get ENOMEM.
Reviewed-by: NGleb Natapov <gleb@redhat.com>
Signed-off-by: NAlex Williamson <alex.williamson@redhat.com>
Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>

The API documents that only flags and guest physical memory space can
be modified on an existing slot, but we don't enforce that the
userspace address cannot be modified.  Instead we just ignore it.
This means that a user may think they've successfully moved both the
guest and user addresses, when in fact only the guest address changed.
Check and error instead.
Reviewed-by: NGleb Natapov <gleb@redhat.com>
Signed-off-by: NAlex Williamson <alex.williamson@redhat.com>
Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>

The API documentation states:

	When changing an existing slot, it may be moved in the guest
	physical memory space, or its flags may be modified.

An "existing slot" requires a non-zero npages (memory_size).  The only
transition we should therefore allow for a non-existing slot should be
to create the slot, which includes setting a non-zero memory_size.  We
currently allow calls to modify non-existing slots, which is pointless,
confusing, and possibly wrong.

With this we know that the invalidation path of __kvm_set_memory_region
is always for a delete or move and never for adding a zero size slot.
Reviewed-by: NGleb Natapov <gleb@redhat.com>
Signed-off-by: NAlex Williamson <alex.williamson@redhat.com>
Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>

Typo for the next pointer means we're walking random data here.
Signed-off-by: NAlex Williamson <alex.williamson@redhat.com>
Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>

The current eventfd code assumes that when we have eventfd, we also have
irqfd for in-kernel interrupt delivery. This is not necessarily true. On
PPC we don't have an in-kernel irqchip yet, but we can still support easily
support eventfd.
Signed-off-by: NAlexander Graf <agraf@suse.de>

We can deliver certain interrupts, notably MSI,
from atomic context.  Use kvm_set_irq_inatomic,
to implement an irq handler for msi.

This reduces the pressure on scheduler in case
where host and guest irq share a host cpu.
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NGleb Natapov <gleb@redhat.com>

Add an API to inject IRQ from atomic context.
Return EWOULDBLOCK if impossible (e.g. for multicast).
Only MSI is supported ATM.
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NGleb Natapov <gleb@redhat.com>

Prior to memory slot sorting this loop compared all of the user memory
slots for overlap with new entries.  With memory slot sorting, we're
just checking some number of entries in the array that may or may not
be user slots.  Instead, walk all the slots with kvm_for_each_memslot,
which has the added benefit of terminating early when we hit the first
empty slot, and skip comparison to private slots.

Cc: stable@vger.kernel.org
Signed-off-by: NAlex Williamson <alex.williamson@redhat.com>
Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>

TSC initialization will soon make use of online_vcpus.
Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>

KVM added a global variable to guarantee monotonicity in the guest.
One of the reasons for that is that the time between

	1. ktime_get_ts(&timespec);
	2. rdtscll(tsc);

Is variable. That is, given a host with stable TSC, suppose that
two VCPUs read the same time via ktime_get_ts() above.

The time required to execute 2. is not the same on those two instances
executing in different VCPUS (cache misses, interrupts...).

If the TSC value that is used by the host to interpolate when
calculating the monotonic time is the same value used to calculate
the tsc_timestamp value stored in the pvclock data structure, and
a single <system_timestamp, tsc_timestamp> tuple is visible to all
vcpus simultaneously, this problem disappears. See comment on top
of pvclock_update_vm_gtod_copy for details.

Monotonicity is then guaranteed by synchronicity of the host TSCs
and guest TSCs.

Set TSC stable pvclock flag in that case, allowing the guest to read
clock from userspace.
Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>

No need to check return value before breaking switch.
Signed-off-by: NGuo Chao <yan@linux.vnet.ibm.com>
Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>

We should avoid kfree()ing error pointer in kvm_vcpu_ioctl() and
kvm_arch_vcpu_ioctl().
Signed-off-by: NGuo Chao <yan@linux.vnet.ibm.com>
Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>

This patch filters noslot pfn out from error pfns based on Marcelo comment:
noslot pfn is not a error pfn

After this patch,
- is_noslot_pfn indicates that the gfn is not in slot
- is_error_pfn indicates that the gfn is in slot but the error is occurred
  when translate the gfn to pfn
- is_error_noslot_pfn indicates that the pfn either it is error pfns or it
  is noslot pfn
And is_invalid_pfn can be removed, it makes the code more clean
Signed-off-by: NXiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>
Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>

We can not directly call kvm_release_pfn_clean to release the pfn
since we can meet noslot pfn which is used to cache mmio info into
spte
Signed-off-by: NXiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>
Cc: stable@vger.kernel.org
Signed-off-by: NAvi Kivity <avi@redhat.com>

Change existing kernel error message to include return value from
iommu_attach_device() when it fails. This will help debug device
assignment failures more effectively.
Signed-off-by: NShuah Khan <shuah.khan@hp.com>
Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>

Now that we have defined generic set_bit_le() we do not need to use
test_and_set_bit_le() for atomically setting a bit.
Signed-off-by: NTakuya Yoshikawa <yoshikawa.takuya@oss.ntt.co.jp>
Cc: Avi Kivity <avi@redhat.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

To emulate level triggered interrupts, add a resample option to
KVM_IRQFD.  When specified, a new resamplefd is provided that notifies
the user when the irqchip has been resampled by the VM.  This may, for
instance, indicate an EOI.  Also in this mode, posting of an interrupt
through an irqfd only asserts the interrupt.  On resampling, the
interrupt is automatically de-asserted prior to user notification.
This enables level triggered interrupts to be posted and re-enabled
from vfio with no userspace intervention.

All resampling irqfds can make use of a single irq source ID, so we
reserve a new one for this interface.
Signed-off-by: NAlex Williamson <alex.williamson@redhat.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

Most interrupt are delivered to only one vcpu. Use pre-build tables to
find interrupt destination instead of looping through all vcpus. In case
of logical mode loop only through vcpus in a logical cluster irq is sent
to.
Signed-off-by: NGleb Natapov <gleb@redhat.com>
Acked-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

vcpu mutex can be held for unlimited time so
taking it with mutex_lock on an ioctl is wrong:
one process could be passed a vcpu fd and
call this ioctl on the vcpu used by another process,
it will then be unkillable until the owner exits.

Call mutex_lock_killable instead and return status.
Note: mutex_lock_interruptible would be even nicer,
but I am not sure all users are prepared to handle EINTR
from these ioctls. They might misinterpret it as an error.

Cleanup paths expect a vcpu that can't be used by
any userspace so this will always succeed - catch bugs
by calling BUG_ON.

Catch callers that don't check return state by adding
__must_check.
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>

Other arches do not need this.
Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>

v2: fix incorrect deletion of mmio sptes on gpa move (noticed by Takuya)
Signed-off-by: NAvi Kivity <avi@redhat.com>

PPC must flush all translations before the new memory slot
is visible.
Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

Introducing kvm_arch_flush_shadow_memslot, to invalidate the
translations of a single memory slot.
Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

The build error was caused by that builtin functions are calling
the functions implemented in modules. This error was introduced by
commit 4d8b81ab ("KVM: introduce readonly memslot").

The patch fixes the build error by moving function __gfn_to_hva_memslot()
from kvm_main.c to kvm_host.h and making that "inline" so that the
builtin function (kvmppc_h_enter) can use that.
Acked-by: NPaul Mackerras <paulus@samba.org>
Signed-off-by: NGavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>

KVM_SET_SIGNAL_MASK passed a NULL argument leaves the on stack signal
sets uninitialized. It then passes them through to
kvm_vcpu_ioctl_set_sigmask.

We should be passing a NULL in this case not translated garbage.
Signed-off-by: NAlan Cox <alan@linux.intel.com>
Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>

In current code, if we map a readonly memory space from host to guest
and the page is not currently mapped in the host, we will get a fault
pfn and async is not allowed, then the vm will crash

We introduce readonly memory region to map ROM/ROMD to the guest, read access
is happy for readonly memslot, write access on readonly memslot will cause
KVM_EXIT_MMIO exit
Signed-off-by: NXiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

Then, remove bad_hva and inline kvm_is_error_hva
Signed-off-by: NXiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

In current code, we always map writable pfn for the read fault, in order
to support readonly memslot, we map writable pfn only if 'writable'
is not NULL
Signed-off-by: NXiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

We do too many things in hva_to_pfn, this patch reorganize the code,
let it be better readable
Signed-off-by: NXiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

This set of functions is only used to read data from host space, in the
later patch, we will only get a readonly hva in gfn_to_hva_read, and
the function name is a good hint to let gfn_to_hva_read to pair with
kvm_read_hva()/kvm_read_hva_atomic()
Signed-off-by: NXiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

It can instead of hva_to_pfn_atomic
Signed-off-by: NXiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

Check flags when memslot is registered from userspace as Avi's suggestion
Signed-off-by: NXiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>