According to the POP specification, the parameter blocks of various
functions like the IO instructions are accessed with logical addresses.
Thus we need a function that can read or write a buffer from/to the
guest's logical address space.
This patch now provides a function that can be used to access virtual
guest memory by using the mmu_translate function of QEMU to convert
the virtual addresses to physical.
Signed-off-by: Thomas Huth <thuth@linux.vnet.ibm.com>
Signed-off-by: Jens Freimann <jfrei@linux.vnet.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Program access exceptions are defined to deliver a translation exception
code in the low-core. Add a function trigger_access_exception() that
generates the proper program interrupt on both KVM and non-KVM systems
and switch the existing code to use it.
Signed-off-by: Thomas Huth <thuth@linux.vnet.ibm.com>
Signed-off-by: Jens Freimann <jfrei@linux.vnet.ibm.com>
Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
We can get rid of the switch(asc) in mmu_translate_asc() by simply
selecting the right control register ASCE in the mmu_translate()
function already.
This patch is based on an original patch/idea by Ralf Hoppe.
Signed-off-by: Thomas Huth <thuth@linux.vnet.ibm.com>
Signed-off-by: Jens Freimann <jfrei@linux.vnet.ibm.com>
Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Bit 52 in a page table entry has always to be zero, or a translation
specification exception is to be recognized.
Signed-off-by: Thomas Huth <thuth@linux.vnet.ibm.com>
Signed-off-by: Jens Freimann <jfrei@linux.vnet.ibm.com>
Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
An Address Space Control Element (ASCE) is only the very first unit of
an s390 address translation (normally residing in one of the control
registers). The entries in the page tables are called differently.
So let's call the relevant variable pt_entry instead of asce in
mmu_translate_pte() to avoid future confusion (thus there is no
functional change in this patch, just renaming).
Signed-off-by: Thomas Huth <thuth@linux.vnet.ibm.com>
Signed-off-by: Jens Freimann <jfrei@linux.vnet.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
If the "DAT-protection" bit is set in the region table entry and EDAT is
enabled, only read accesses are allowed in the corresponding memory area.
Signed-off-by: Thomas Huth <thuth@linux.vnet.ibm.com>
Signed-off-by: Jens Freimann <jfrei@linux.vnet.ibm.com>
Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Each different level of region/segment table has a dedicated
exception type for illegal entries.
Signed-off-by: Thomas Huth <thuth@linux.vnet.ibm.com>
Signed-off-by: Jens Freimann <jfrei@linux.vnet.ibm.com>
Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
If an ASCE has illegal bits set, an ASCE-type exception should be
generated instead of a translation specification exception.
Signed-off-by: Thomas Huth <thuth@linux.vnet.ibm.com>
Signed-off-by: Jens Freimann <jfrei@linux.vnet.ibm.com>
Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
The address space bits in the translation exception code were wrong.
In fact, we can simply copy the bits from the PSW, so there's no need
for the trans_bits() function anymore.
Additionally, we now also set the fetch/store bits in the translation
exception code, so a guest can determine whether the exception occured
during a write or during a read.
Signed-off-by: Thomas Huth <thuth@linux.vnet.ibm.com>
Signed-off-by: Jens Freimann <jfrei@linux.vnet.ibm.com>
Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
When a fault occurs during the MMU lookup in s390_cpu_get_phys_page_debug(),
the trigger_page_fault() function writes the translation exception code
into the lowcore - something you would not expect during a memory access
by the debugger. Ease this problem by adding an additional parameter to
mmu_translate() which can be used to specify whether a program check and
the translation exception code should be injected or not.
Signed-off-by: Thomas Huth <thuth@linux.vnet.ibm.com>
Signed-off-by: Jens Freimann <jfrei@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
The ACSEs have a table length field and the region entries have
table length and offset fields which must be checked during
translation to see whether the given virtual address is really
covered by the translation table.
Signed-off-by: Thomas Huth <thuth@linux.vnet.ibm.com>
Signed-off-by: Jens Freimann <jfrei@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
The current code used a wrong and very confusing way of dealing with
the table levels by introducing a "fake level above current". However,
the real problem was simply that the checks for the region/segment
invalid bit and for the matching region/segment level was done at the
wrong spot in the code - it has to be done after the first table entry
has been looked up instead (e.g. there is also no "invalid" bit in the
ASCE itself and the current "level" has to be the same as the level in
the entry that we just looked up).
Also the entries for the segment table are quite a bit different compared
to the region table entries. So this patch moves the related code into the
function mmu_translate_segment() to make it clear at which table level we
currently are and to get rid of the ugly switch-statement in the function
mmu_translate_region().
Signed-off-by: Thomas Huth <thuth@linux.vnet.ibm.com>
Signed-off-by: Jens Freimann <jfrei@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
The real-space designation bits live in the ASCEs, not in the table entries,
so the check must be done before we start walking the MMU table.
Signed-off-by: Thomas Huth <thuth@linux.vnet.ibm.com>
Signed-off-by: Jens Freimann <jfrei@linux.vnet.ibm.com>
Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
helper.c is quite overcrowded already, so let's move the MMU
translation to a separate file instead (like it has been done
with the other targets already).
Signed-off-by: Thomas Huth <thuth@linux.vnet.ibm.com>
Signed-off-by: Jens Freimann <jfrei@linux.vnet.ibm.com>
Acked-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
