When we get a performance counter interrupt we need to route it on to the
Linux handler after we got out of the guest context. We also need to tell
our handling code that this particular interrupt doesn't need treatment.

So let's add those two bits in, making perf work while having a KVM guest
running.
Signed-off-by: NAlexander Graf <agraf@suse.de>
Signed-off-by: NAvi Kivity <avi@redhat.com>

There are some pieces in the code that I overlooked that still use
u64s instead of longs. This slows down 32 bit hosts unnecessarily, so
let's just move them to ulong.
Signed-off-by: NAlexander Graf <agraf@suse.de>
Signed-off-by: NAvi Kivity <avi@redhat.com>

Now that we have all the bits and pieces in place, let's enable building
of the Book3S_32 target.
Signed-off-by: NAlexander Graf <agraf@suse.de>
Signed-off-by: NAvi Kivity <avi@redhat.com>

When an interrupt occurs we don't know yet if we're in guest context or
in host context. When in guest context, KVM needs to handle it.

So let's pull the same trick we did on Book3S_64: Just add a macro to
determine if we're in guest context or not and if so jump on to KVM code.

CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: NAlexander Graf <agraf@suse.de>
Acked-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: NAvi Kivity <avi@redhat.com>

We have a define on what the highest bit of IRQ priorities is. So we can
just as well use it in the bit checking code and avoid invalid IRQ values
to be triggered.
Signed-off-by: NAlexander Graf <agraf@suse.de>
Signed-off-by: NAvi Kivity <avi@redhat.com>

We need the SWITCH_FRAME_SIZE define on Book3S_32 now too.
So let's export it unconditionally.

CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: NAlexander Graf <agraf@suse.de>
Acked-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: NAvi Kivity <avi@redhat.com>

Our shadow MMU code needs to know where the HTAB is located and how
big it is. So we need some variables from the kernel exported to
module space if KVM is built as a module.

CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: NAlexander Graf <agraf@suse.de>
Acked-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: NAvi Kivity <avi@redhat.com>

Some code we had so far required defines and had code that was completely
Book3S_64 specific. Since we now opened book3s.c to Book3S_32 too, we need
to take care of these pieces.

So let's add some minor code where it makes sense to not go the Book3S_64
code paths and add compat defines on others.
Signed-off-by: NAlexander Graf <agraf@suse.de>
Signed-off-by: NAvi Kivity <avi@redhat.com>

Book3S_32 doesn't know about segment faults. It only knows about page faults.
So in order to know that we didn't map a segment, we need to fake segment
faults.

We do this by setting invalid segment registers to an invalid VSID and then
check for that VSID on normal page faults.
Signed-off-by: NAlexander Graf <agraf@suse.de>
Signed-off-by: NAvi Kivity <avi@redhat.com>

We need to keep the pointer to the shadow vcpu somewhere accessible from
within really early interrupt code. The best fit I found was the thread
struct, as that resides in an SPRG.

So let's put a pointer to the shadow vcpu in the thread struct and add
an asm-offset so we can find it.
Signed-off-by: NAlexander Graf <agraf@suse.de>
Signed-off-by: NAvi Kivity <avi@redhat.com>

When instruction fetch failed, the inline function hook automatically
detects that and starts the internal guest memory load function. So
whenever we access kvmppc_get_last_inst(), we're sure the result is sane.
Signed-off-by: NAlexander Graf <agraf@suse.de>
Signed-off-by: NAvi Kivity <avi@redhat.com>

When we mapped a page as read-only, we can just release it as clean to
KVM's page claim mechanisms, because we're pretty sure it hasn't been
touched.
Signed-off-by: NAlexander Graf <agraf@suse.de>
Signed-off-by: NAvi Kivity <avi@redhat.com>

We just introduced generic segment switching code that only needs to call
small macros to do the actual switching, but keeps most of the entry / exit
code generic.

So let's move the SLB switching code over to use this new mechanism.
Signed-off-by: NAlexander Graf <agraf@suse.de>
Signed-off-by: NAvi Kivity <avi@redhat.com>

Since we now have several fields in the shadow VCPU, we also change
the internal calling convention between the different entry/exit code
layers.

Let's reflect that in the IR=1 code and make sure we use "long" defines
for long field access.
Signed-off-by: NAlexander Graf <agraf@suse.de>
Signed-off-by: NAvi Kivity <avi@redhat.com>

The real mode handler code was originally writen for 64 bit Book3S only.
But since we not add 32 bit functionality too, we need to make some tweaks
to it.

This patch basically combines using the "long" access defines and using
fields from the shadow VCPU we just moved there.
Signed-off-by: NAlexander Graf <agraf@suse.de>
Signed-off-by: NAvi Kivity <avi@redhat.com>

The host shadow mmu code needs to get initialized. It needs to fetch a
segment it can use to put shadow PTEs into.

That initialization code was in generic code, which is icky. Let's move
it over to the respective MMU file.
Signed-off-by: NAlexander Graf <agraf@suse.de>
Signed-off-by: NAvi Kivity <avi@redhat.com>

The shadow vcpu now contains some fields we don't use from the vcpu anymore.
Access to them happens using inline functions that happily use the shadow
vcpu fields.

So let's now ifdef them out to booke only and add asm-offsets.
Signed-off-by: NAlexander Graf <agraf@suse.de>
Signed-off-by: NAvi Kivity <avi@redhat.com>

For assembly code there are several "long" load and store defines already.
The one that's missing is the typical stack store, stdu/stwu.

So let's add that define as well, making my KVM code happy.

CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: NAlexander Graf <agraf@suse.de>
Acked-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: NAvi Kivity <avi@redhat.com>

Upstream recently added a new name for PPC64: Book3S_64.

So instead of using CONFIG_PPC64 we should use CONFIG_PPC_BOOK3S consotently.
That makes understanding the code easier (I hope).
Signed-off-by: NAlexander Graf <agraf@suse.de>
Signed-off-by: NAvi Kivity <avi@redhat.com>

So far we had a lot of conditional code on CONFIG_KVM_BOOK3S_64_HANDLER.
As we're moving towards common code between 32 and 64 bits, most of
these ifdefs can be moved to a more generic term define, called
CONFIG_KVM_BOOK3S_HANDLER.

This patch adds the new generic config option and moves ifdefs over.
Signed-off-by: NAlexander Graf <agraf@suse.de>
Signed-off-by: NAvi Kivity <avi@redhat.com>

We already have some inline fuctions we use to access vcpu or svcpu structs,
depending on whether we're on booke or book3s. Since we just put a few more
registers into the svcpu, we also need to make sure the respective callbacks
are available and get used.

So this patch moves direct use of the now in the svcpu struct fields to
inline function calls. While at it, it also moves the definition of those
inline function calls to respective header files for booke and book3s,
greatly improving readability.
Signed-off-by: NAlexander Graf <agraf@suse.de>
Signed-off-by: NAvi Kivity <avi@redhat.com>

After a lot of thought on how to make the entry / exit code easier,
I figured it'd be clever to put even more register state into the
shadow vcpu. That way we have more registers available to use, making
the code easier to read.

So this patch adds a few new fields to that shadow vcpu. Later on we
will remove the originals from the vcpu and paca.
Signed-off-by: NAlexander Graf <agraf@suse.de>
Signed-off-by: NAvi Kivity <avi@redhat.com>

In analogy to the 64 bit specific header file, this is the 32 bit
pendant. With this in place we can just always call to_svcpu and
be assured we get the right pointer anywhere.
Signed-off-by: NAlexander Graf <agraf@suse.de>
Signed-off-by: NAvi Kivity <avi@redhat.com>

In the process of generalizing as much code as possible, I also moved
the shadow vcpu code together to a generic book3s file. Unfortunately
the location of the shadow vcpu is different on 32 and 64 bit, so we
need a wrapper function to tell us where it is.

That sounded like a perfect fit for a subarch specific header file.
Here we can put anything that needs to be different between those two.
Signed-off-by: NAlexander Graf <agraf@suse.de>
Signed-off-by: NAvi Kivity <avi@redhat.com>

We need to reserve a context from KVM to make sure we have our own
segment space. While we did that split for Book3S_64 already, 32 bit
is still outstanding.

So let's split it now.
Signed-off-by: NAlexander Graf <agraf@suse.de>
Acked-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: NAvi Kivity <avi@redhat.com>

This is the code that will later be used instead of book3s_64_slb.S. It
does the last step of guest entry and the first generic steps of guest
exiting, once we have determined the interrupt is a KVM interrupt.

It also reads the last used instruction from the guest virtual address
space if necessary, to speed up that path.

The new thing about this file is that it makes use of generic long load
and store functions and calls a macro to fill in the actual segment
switching code. That still needs to be done differently for book3s_32 and
book3s_64.
Signed-off-by: NAlexander Graf <agraf@suse.de>
Signed-off-by: NAvi Kivity <avi@redhat.com>

Later in this series we will move the current segment switch code to
generic code and make that call hooks for the specific sub-archs (32
vs. 64 bit). This is the hook for 32 bits.

It enabled the entry and exit code to swap segment registers with
values from the shadow cpu structure.
Signed-off-by: NAlexander Graf <agraf@suse.de>
Signed-off-by: NAvi Kivity <avi@redhat.com>

In order to support 32 bit Book3S, we need to add code to enable our
shadow MMU to actually add shadow PTEs. This is the module enabling
that support.
Signed-off-by: NAlexander Graf <agraf@suse.de>
Signed-off-by: NAvi Kivity <avi@redhat.com>

We have quite some code that can be used by Book3S_32 and Book3S_64 alike,
so let's call it "Book3S" instead of "Book3S_64", so we can later on
use it from the 32 bit port too.
Signed-off-by: NAlexander Graf <agraf@suse.de>
Signed-off-by: NAvi Kivity <avi@redhat.com>

Since gfn is not changed in the for loop, we do not need to call
gfn_to_memslot_unaliased() under the loop, and it is safe to move
it out.
Signed-off-by: NWei Yongjun <yjwei@cn.fujitsu.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

Nobody use gva_to_page() anymore, get rid of it.
Signed-off-by: NGui Jianfeng <guijianfeng@cn.fujitsu.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

Remove unused varialbe in rmap_next()
Signed-off-by: NGui Jianfeng <guijianfeng@cn.fujitsu.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

Make use of is_large_pte() instead of checking PT_PAGE_SIZE_MASK
bit directly.
Signed-off-by: NGui Jianfeng <guijianfeng@cn.fujitsu.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

Move first pte address calculation out of loop to save some cycles.
Signed-off-by: NGui Jianfeng <guijianfeng@cn.fujitsu.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

When CPU_UP_CANCELED, hardware_enable() has not been called at the CPU
which is going up because raw_notifier_call_chain(CPU_ONLINE)
has not been called for this cpu.

Drop the handling for CPU_UP_CANCELED.
Signed-off-by: NLai Jiangshan <laijs@cn.fujitsu.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

Since commit bf47a760, we no longer handle ptes with the global bit
set specially, so there is no reason to distinguish between shadow pages
created with cr4.gpe set and clear.

Such tracking is expensive when the guest toggles cr4.pge, so drop it.
Signed-off-by: NAvi Kivity <avi@redhat.com>

The RCU/SRCU API have already changed for proving RCU usage.

I got the following dmesg when PROVE_RCU=y because we used incorrect API.
This patch coverts rcu_deference() to srcu_dereference() or family API.

===================================================
[ INFO: suspicious rcu_dereference_check() usage. ]
---------------------------------------------------
arch/x86/kvm/mmu.c:3020 invoked rcu_dereference_check() without protection!

other info that might help us debug this:

rcu_scheduler_active = 1, debug_locks = 0
2 locks held by qemu-system-x86/8550:
 #0:  (&kvm->slots_lock){+.+.+.}, at: [<ffffffffa011a6ac>] kvm_set_memory_region+0x29/0x50 [kvm]
 #1:  (&(&kvm->mmu_lock)->rlock){+.+...}, at: [<ffffffffa012262d>] kvm_arch_commit_memory_region+0xa6/0xe2 [kvm]

stack backtrace:
Pid: 8550, comm: qemu-system-x86 Not tainted 2.6.34-rc4-tip-01028-g939eab1 #27
Call Trace:
 [<ffffffff8106c59e>] lockdep_rcu_dereference+0xaa/0xb3
 [<ffffffffa012f6c1>] kvm_mmu_calculate_mmu_pages+0x44/0x7d [kvm]
 [<ffffffffa012263e>] kvm_arch_commit_memory_region+0xb7/0xe2 [kvm]
 [<ffffffffa011a5d7>] __kvm_set_memory_region+0x636/0x6e2 [kvm]
 [<ffffffffa011a6ba>] kvm_set_memory_region+0x37/0x50 [kvm]
 [<ffffffffa015e956>] vmx_set_tss_addr+0x46/0x5a [kvm_intel]
 [<ffffffffa0126592>] kvm_arch_vm_ioctl+0x17a/0xcf8 [kvm]
 [<ffffffff810a8692>] ? unlock_page+0x27/0x2c
 [<ffffffff810bf879>] ? __do_fault+0x3a9/0x3e1
 [<ffffffffa011b12f>] kvm_vm_ioctl+0x364/0x38d [kvm]
 [<ffffffff81060cfa>] ? up_read+0x23/0x3d
 [<ffffffff810f3587>] vfs_ioctl+0x32/0xa6
 [<ffffffff810f3b19>] do_vfs_ioctl+0x495/0x4db
 [<ffffffff810e6b2f>] ? fget_light+0xc2/0x241
 [<ffffffff810e416c>] ? do_sys_open+0x104/0x116
 [<ffffffff81382d6d>] ? retint_swapgs+0xe/0x13
 [<ffffffff810f3ba6>] sys_ioctl+0x47/0x6a
 [<ffffffff810021db>] system_call_fastpath+0x16/0x1b
Signed-off-by: NLai Jiangshan <laijs@cn.fujitsu.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

Signed-off-by: NAvi Kivity <avi@redhat.com>

Quote from Avi:

|Just change the assignment to a 'goto restart;' please,
|I don't like playing with list_for_each internals.
Signed-off-by: NXiao Guangrong <xiaoguangrong@cn.fujitsu.com>
Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>

If kvm_task_switch() fails code exits to userspace without specifying
exit reason, so the previous exit reason is reused by userspace. Fix
this by specifying exit reason correctly.
Signed-off-by: NGleb Natapov <gleb@redhat.com>
Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>