Setup the 4.1 compatibility model so we can add new features to the
LATEST model.
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
IEP support in the mmu is fairly easy. Set the right permissions for TLB
entries and properly report an exception.
Make sure to handle EDAT-2 by setting bit 56/60/61 of the TEID (TEC) to
the right values.
Let's keep s390_cpu_get_phys_page_debug() working even if IEP is
active. Switch MMU_DATA_LOAD - this has no other effects any more as the
ASC to be used is now fully selected outside of mmu_translate().
Reviewed-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
We already implement ESOP-1. For ESOP-2, we only have to indicate all
protection exceptions properly. Due to EDAT-1, we already indicate DAT
exceptions properly. We don't trigger KCP/ALCP/IEP exceptions yet.
So all we have to do is set the TEID (TEC) to the right values
(bit 56, 60, 61) in case of LAP.
We don't have any side-effects (e.g., no guarded-storage facility),
therefore, bit 64 of the TEID (TEC) is always 0.
We always have to indicate whether it is a fetch or a store for all access
exceptions. This is only missing for LAP exceptions.
Acked-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
This only adds basic support to the DAT translation, but no EDAT2 support
for TCG. E.g., the gdbstub under kvm uses this function, too, to
translate virtual addresses.
Reviewed-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
A non-recursive implementation allows to make better use of the
branch predictor, avoids function calls, and makes the implementation of
new features only for a subset of region table levels easier.
We can now directly compare our implementation to the KVM gaccess
implementation in arch/s390/kvm/gaccess.c:guest_translate().
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Let's use consistent names for the region/section/page table entries and
for the macros to extract relevant parts from virtual address. Make them
match the definitions in the PoP - e.g., how the relevant bits are actually
called.
Introduce defines for all bits declared in the PoP. This will come in
handy in follow-up patches.
Add a note where additional information about s390x and the used
definitions can be found.
Acked-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
While ASCE_ORIGIN is not wrong, it is certainly confusing. We want a
page frame address.
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Let's document how it works and inject PGM_ADDRESSING if reading of
table entries fails.
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Let's return the PGM from the translation functions on error and inject
based on that.
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
We'll reuse the ilen and tec definitions in mmu_translate
soon also for all other DAT exceptions we inject. Move it to the caller,
where we can later pair it up with other protection checks, like IEP.
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Let's get it out of the way to make some further refactorings easier.
Personally, I've never used these debug statements at all. And if I had
to debug issues, I used plain GDB instead (debug prints are just way too
much noise in the MMU). We might want to introduce tracing at some point
instead, so we can able selected events on demand.
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Instead of splitting at an unaligned address, we can simply split at
4TB.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: Igor Mammedov <imammedo@redhat.com>
s390 was trying to solve limited KVM memslot size issue by abusing
memory_region_allocate_system_memory(), which breaks API contract
where the function might be called only once.
Beside an invalid use of API, the approach also introduced migration
issue, since RAM chunks for each KVM_SLOT_MAX_BYTES are transferred in
migration stream as separate RAMBlocks.
After discussion [1], it was agreed to break migration from older
QEMU for guest with RAM >8Tb (as it was relatively new (since 2.12)
and considered to be not actually used downstream).
Migration should keep working for guests with less than 8TB and for
more than 8TB with QEMU 4.2 and newer binary.
In case user tries to migrate more than 8TB guest, between incompatible
QEMU versions, migration should fail gracefully due to non-exiting
RAMBlock ID or RAMBlock size mismatch.
Taking in account above and that now KVM code is able to split too
big MemorySection into several memslots, partially revert commit
(bb223055b s390-ccw-virtio: allow for systems larger that 7.999TB)
and use kvm_set_max_memslot_size() to set KVMSlot size to
KVM_SLOT_MAX_BYTES.
1) [PATCH RFC v2 4/4] s390: do not call memory_region_allocate_system_memory() multiple times
Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Message-Id: <20190924144751.24149-5-imammedo@redhat.com>
Acked-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Each operand can have a maximum length of 16. Make sure to prepare all
reads/writes before writing.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Access at most single pages and document why. Using the access helpers
might over-indicate watchpoints within the same page, I guess we can
live with that.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
We can process a maximum of 256 bytes, crossing two pages.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
We can process a maximum of 256 bytes, crossing two pages.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
We can process a maximum of 256 bytes, crossing two pages. Calculate the
accessed range upfront - src is accessed right-to-left.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
We can process a maximum of 256 bytes, crossing two pages.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
We can process a maximum of 256 bytes, crossing two pages. While at it,
increment the length once.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
We can process a maximum of 256 bytes, crossing two pages.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
The last remaining bit is padding with two bytes.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
The last remaining bit for MVC is handling destructive overlaps in a
fault-safe way.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
As we are moving between address spaces, we can use access_memmove()
without checking for destructive overlaps (especially of real storage
locations):
"Each storage operand is processed left to right. The
storage-operand-consistency rules are the same as
for MOVE (MVC), except that when the operands
overlap in real storage, the use of the common real-
storage locations is not necessarily recognized."
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Replace fast_memmove() variants by access_memmove() variants, that
first try to probe access to all affected pages (maximum is two pages).
Introduce access_get_byte()/access_set_byte(). We might be able to speed
up memmove in special cases even further (do single-byte access, use
memmove() for remaining bytes in page), however, we'll skip that for now.
In MVCOS, simply always call access_memmove_as() and drop the TODO
about LAP. LAP is already handled in the MMU.
Get rid of adj_len_to_page(), which is now unused.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Replace fast_memset() by access_memset(), that first tries to probe
access to all affected pages (maximum is two). We'll use the same
mechanism for other types of accesses soon.
Only in very rare cases (especially TLB_NOTDIRTY), we'll have to
fallback to ld/st helpers. Try to speed up that case as suggested by
Richard.
We'll rework most involved handlers soon to do all accesses via new
fault-safe helpers, especially MVC.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Although we basically ignore the index all the time for CONFIG_USER_ONLY,
let's simply skip all the checks and always return MMU_USER_IDX in
cpu_mmu_index() and get_mem_index().
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
24 and 31-bit address space handling is wrong when it comes to storing
back the addresses to the register.
While at it, read gprs 0 implicitly.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Bit position 32-55 of general register 0 must be zero.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
... and don't perform any move in case the length is zero.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Triggered by a review comment from Richard, also MVCOS has a 32-bit
length in 24/31-bit addressing mode. Add a new helper.
Rename wrap_length() to wrap_length31().
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Let's stay within single pages.
... and indicate cc=3 in case there is work remaining. Keep unicode
padding simple.
While reworking, properly wrap the addresses.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
We have to mask of any unused bits. While at it, document what exactly is
missing.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Perform the checks documented in the PoP.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Let's use the new helper, that also detects destructive overlaps when
wrapping.
We'll make the remaining code (e.g., fast_memmove()) aware of wrapping
later.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Let's increment the length once.
While at it, cleanup the comment. The memset() example is given as a
programming note in the PoP, so drop the description.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Process max 4k bytes at a time, writing back registers between the
accesses. The instruction is interruptible.
"For operands longer than 2K bytes, access exceptions are not
recognized for locations more than 2K bytes beyond the current location
being processed."
Note that on z/Architecture, 2k vs. 4k access cannot get differentiated as
long as pages are not crossed. This seems to be a leftover from ESA/390.
Simply stay within single pages.
MVCL handling is quite different than MVCLE/MVCLU handling, so split up
the handlers.
Defer interrupt handling, as that will require more thought, add a TODO
for that.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
We'll have to zero-out unused bit positions, so make sure to write the
addresses back.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
We have to zero out unused bits in 24 and 31-bit addressing mode.
Provide a new helper.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
We use the marker "-1" for "no exception". s390_cpu_do_interrupt() might
get confused by that.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Since QEMU v2.10, the KVM acceleration does not work on older kernels
anymore since the code accidentally requires the KVM_CAP_DEVICE_CTRL
capability now - it should have been optional instead.
Instead of fixing the bug, we asked in the ChangeLog of QEMU 2.11 - 3.0
that people should speak up if they still need support of QEMU running
with KVM on older kernels, but seems like nobody really complained.
Thus let's make this official now and turn it into a proper error
message, telling the users to use at least kernel 3.15 now.
Signed-off-by: Thomas Huth <thuth@redhat.com>
Message-Id: <20190913091443.27565-1-thuth@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
... and also call it for CONFIG_USER_ONLY. This function probably will
also need some refactoring in regards to probing, however, we'll have to
come back to that later, once cleaning up the other mem helpers.
The alignment check always makes sure that the write access falls into a
single page.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20190826075112.25637-8-david@redhat.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Factor it out into common code. Similar to the !CONFIG_USER_ONLY variant,
let's not allow to cross page boundaries.
Signed-off-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20190826075112.25637-4-david@redhat.com>
[rth: Move cpu & cc variables inside if block.]
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Hm... how did that "-" slip in (-TAGRET_PAGE_SIZE would be correct). This
currently makes us exceed one page in a single probe_write() call,
essentially leaving some memory unchecked.
Fixes: c5a7392cfb ("s390x/tcg: Provide probe_write_access helper")
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Message-Id: <20190826075112.25637-3-david@redhat.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
If I'm not completely wrong, we are dealing with guest addresses here
and not with host addresses. Use the right check.
Fixes: c5a7392cfb ("s390x/tcg: Provide probe_write_access helper")
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Message-Id: <20190826075112.25637-2-david@redhat.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Preparation for collapsing the two byte swaps, adjust_endianness and
handle_bswap, along the I/O path.
Target dependant attributes are conditionalized upon NEED_CPU_H.
Signed-off-by: Tony Nguyen <tony.nguyen@bt.com>
Acked-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Acked-by: Cornelia Huck <cohuck@redhat.com>
Message-Id: <81d9cd7d7f5aaadfa772d6c48ecee834e9cf7882.1566466906.git.tony.nguyen@bt.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Factor it out, add a comment how it all works, and also use it in the
REAL MMU.
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20190816084708.602-7-david@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
