Commit Graph

1064 Commits

Author SHA1 Message Date
Li Zhijian 0c249ff71c unify len and addr type for memory/address APIs
Some address/memory APIs have different type between
'hwaddr/target_ulong addr' and 'int len'. It is very unsafe, especially
some APIs will be passed a non-int len by caller which might cause
overflow quietly.
Below is an potential overflow case:
    dma_memory_read(uint32_t len)
      -> dma_memory_rw(uint32_t len)
        -> dma_memory_rw_relaxed(uint32_t len)
          -> address_space_rw(int len) # len overflow

CC: Paolo Bonzini <pbonzini@redhat.com>
CC: Peter Crosthwaite <crosthwaite.peter@gmail.com>
CC: Richard Henderson <rth@twiddle.net>
CC: Peter Maydell <peter.maydell@linaro.org>
CC: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: Li Zhijian <lizhijian@cn.fujitsu.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-02-05 16:50:18 +01:00
Murilo Opsfelder Araujo 53adb9d43e mmap-alloc: fix hugetlbfs misaligned length in ppc64
The commit 7197fb4058 ("util/mmap-alloc:
fix hugetlb support on ppc64") fixed Huge TLB mappings on ppc64.

However, we still need to consider the underlying huge page size
during munmap() because it requires that both address and length be a
multiple of the underlying huge page size for Huge TLB mappings.
Quote from "Huge page (Huge TLB) mappings" paragraph under NOTES
section of the munmap(2) manual:

  "For munmap(), addr and length must both be a multiple of the
  underlying huge page size."

On ppc64, the munmap() in qemu_ram_munmap() does not work for Huge TLB
mappings because the mapped segment can be aligned with the underlying
huge page size, not aligned with the native system page size, as
returned by getpagesize().

This has the side effect of not releasing huge pages back to the pool
after a hugetlbfs file-backed memory device is hot-unplugged.

This patch fixes the situation in qemu_ram_mmap() and
qemu_ram_munmap() by considering the underlying page size on ppc64.

After this patch, memory hot-unplug releases huge pages back to the
pool.

Fixes: 7197fb4058
Signed-off-by: Murilo Opsfelder Araujo <muriloo@linux.ibm.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2019-02-04 18:44:20 +11:00
Peter Maydell 5601be3b01 exec.c: Don't reallocate IOMMUNotifiers that are in use
The tcg_register_iommu_notifier() code has a GArray of
TCGIOMMUNotifier structs which it has registered by passing
memory_region_register_iommu_notifier() a pointer to the embedded
IOMMUNotifier field. Unfortunately, if we need to enlarge the
array via g_array_set_size() this can cause a realloc(), which
invalidates the pointer that memory_region_register_iommu_notifier()
put into the MemoryRegion's iommu_notify list. This can result
in segfaults.

Switch the GArray to holding pointers to the TCGIOMMUNotifier
structs, so that we can individually allocate and free them.

Cc: qemu-stable@nongnu.org
Fixes: 1f871c5e6b ("exec.c: Handle IOMMUs in address_space_translate_for_iotlb()")
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20190128174241.5860-1-peter.maydell@linaro.org
2019-02-01 14:55:45 +00:00
Stefan Hajnoczi 047be4ed24 memory: add memory_region_flush_rom_device()
ROM devices go via MemoryRegionOps->write() callbacks for write
operations and do not dirty/invalidate that memory.  Device emulation
must be able to mark memory ranges that have been modified internally
(e.g. using memory_region_get_ram_ptr()).

Introduce the memory_region_flush_rom_device() API for this purpose.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 20190123212234.32068-2-stefanha@redhat.com
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
[PMM: fix block comment style]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2019-01-29 11:46:04 +00:00
Peter Maydell ea7a5330b7 exec.c: Use correct attrs in cpu_memory_rw_debug()
In the softmmu version of cpu_memory_rw_debug(), we ask the
CPU for the attributes to use for the virtual memory access,
and we correctly use those to identify the address space
index. However, we were not passing them in to the
address_space_write_rom() and address_space_rw() functions.

The effect of this was that a memory access from the gdbstub
to a device which had behaviour that was sensitive to the
memory attributes (such as some ARMv8M NVIC registers) was
incorrectly always performed as if non-secure, rather than
using the right security state for the CPU's current state.

Fixes: https://bugs.launchpad.net/qemu/+bug/1812091

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-id: 20190117133834.7480-1-peter.maydell@linaro.org
2019-01-29 11:46:04 +00:00
Paolo Bonzini f481ee2d5e qemu/queue.h: typedef QTAILQ heads
This will be needed when we change the QTAILQ head and elem structs
to unions.  However, it is also consistent with the usage elsewhere
in QEMU for other list head structs (see for example FsMountList).

Note that most QTAILQs only need their name in order to do backwards
walks.  Those do not break with the struct->union change, and anyway
the change will also remove the need to name heads when doing backwards
walks, so those are not touched here.

Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-01-11 15:46:55 +01:00
Paolo Bonzini b58deb344d qemu/queue.h: leave head structs anonymous unless necessary
Most list head structs need not be given a name.  In most cases the
name is given just in case one is going to use QTAILQ_LAST, QTAILQ_PREV
or reverse iteration, but this does not apply to lists of other kinds,
and even for QTAILQ in practice this is only rarely needed.  In addition,
we will soon reimplement those macros completely so that they do not
need a name for the head struct.  So clean up everything, not giving a
name except in the rare case where it is necessary.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-01-11 15:46:55 +01:00
Peter Maydell 3c8133f973 Rename cpu_physical_memory_write_rom() to address_space_write_rom()
The API of cpu_physical_memory_write_rom() is odd, because it
takes an AddressSpace, unlike all the other cpu_physical_memory_*
access functions. Rename it to address_space_write_rom(), and
bring its API into line with address_space_write().

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Message-id: 20181122133507.30950-3-peter.maydell@linaro.org
2018-12-14 13:30:48 +00:00
Peter Maydell 75693e1411 exec.c: Rename cpu_physical_memory_write_rom_internal()
Rename cpu_physical_memory_write_rom_internal() to
address_space_write_rom_internal(), and make it take
MemTxAttrs and return a MemTxResult. This brings its
API into line with address_space_write().

This is an internal function to exec.c; fixing its API
will allow us to change the global function
cpu_physical_memory_write_rom().

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Message-id: 20181122133507.30950-2-peter.maydell@linaro.org
2018-12-14 13:30:48 +00:00
Emilio G. Cota 5005e2537d exec: introduce tlb_init
Paves the way for the addition of a per-TLB lock.

Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Emilio G. Cota <cota@braap.org>
Message-Id: <20181009174557.16125-4-cota@braap.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2018-10-18 18:58:10 -07:00
Thomas Huth c95ac10340 cpu: Provide a proper prototype for target_words_bigendian() in a header
We've got three places already that provide a prototype for this
function in a .c file - that's ugly. Let's provide a proper prototype
in a header instead, with a proper description why this function should
not be used in most cases.

Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
2018-10-17 08:41:43 +02:00
Hikaru Nishida d5dbde4645 hostmem-file: make available memory-backend-file on POSIX-based hosts
Before this change, memory-backend-file object is valid for Linux hosts
only because hostmem-file.c is compiled only on Linux hosts.
However, other POSIX-based hosts (such as macOS) can support
memory-backend-file object in the same way as on Linux hosts.
This patch makes hostmem-file.c and related functions to be compiled on
all POSIX-based hosts to make available memory-backend-file on them.

Signed-off-by: Hikaru Nishida <hikarupsp@gmail.com>
Message-Id: <20180924123205.29651-1-hikarupsp@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-10-02 19:09:13 +02:00
Peter Maydell 55f4e79d79 pc: fixes
This includes nvdimm persistence fixes queued before the release.
 
 Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
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Merge remote-tracking branch 'remotes/mst/tags/for_upstream' into staging

pc: fixes

This includes nvdimm persistence fixes queued before the release.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

# gpg: Signature made Mon 20 Aug 2018 11:38:11 BST
# gpg:                using RSA key 281F0DB8D28D5469
# gpg: Good signature from "Michael S. Tsirkin <mst@kernel.org>"
# gpg:                 aka "Michael S. Tsirkin <mst@redhat.com>"
# Primary key fingerprint: 0270 606B 6F3C DF3D 0B17  0970 C350 3912 AFBE 8E67
#      Subkey fingerprint: 5D09 FD08 71C8 F85B 94CA  8A0D 281F 0DB8 D28D 5469

* remotes/mst/tags/for_upstream:
  migration/ram: ensure write persistence on loading all data to PMEM.
  migration/ram: Add check and info message to nvdimm post copy.
  mem/nvdimm: ensure write persistence to PMEM in label emulation
  hostmem-file: add the 'pmem' option
  configure: add libpmem support
  memory, exec: switch file ram allocation functions to 'flags' parameters
  memory, exec: Expose all memory block related flags.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2018-08-21 10:23:53 +01:00
Peter Maydell 55a7cb144d accel/tcg: Check whether TLB entry is RAM consistently with how we set it up
We set up TLB entries in tlb_set_page_with_attrs(), where we have
some logic for determining whether the TLB entry is considered
to be RAM-backed, and thus has a valid addend field. When we
look at the TLB entry in get_page_addr_code(), we use different
logic for determining whether to treat the page as RAM-backed
and use the addend field. This is confusing, and in fact buggy,
because the code in tlb_set_page_with_attrs() correctly decides
that rom_device memory regions not in romd mode are not RAM-backed,
but the code in get_page_addr_code() thinks they are RAM-backed.
This typically results in "Bad ram pointer" assertion if the
guest tries to execute from such a memory region.

Fix this by making get_page_addr_code() just look at the
TLB_MMIO bit in the code_address field of the TLB, which
tlb_set_page_with_attrs() sets if and only if the addend
field is not valid for code execution.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Tested-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-id: 20180713150945.12348-1-peter.maydell@linaro.org
2018-08-14 17:17:19 +01:00
Junyan He a4de8552b2 hostmem-file: add the 'pmem' option
When QEMU emulates vNVDIMM labels and migrates vNVDIMM devices, it
needs to know whether the backend storage is a real persistent memory,
in order to decide whether special operations should be performed to
ensure the data persistence.

This boolean option 'pmem' allows users to specify whether the backend
storage of memory-backend-file is a real persistent memory. If
'pmem=on', QEMU will set the flag RAM_PMEM in the RAM block of the
corresponding memory region. If 'pmem' is set while lack of libpmem
support, a error is generated.

Signed-off-by: Junyan He <junyan.he@intel.com>
Signed-off-by: Haozhong Zhang <haozhong.zhang@intel.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2018-08-10 13:29:39 +03:00
Junyan He cbfc017103 memory, exec: switch file ram allocation functions to 'flags' parameters
As more flag parameters besides the existing 'share' are going to be
added to following functions
memory_region_init_ram_from_file
qemu_ram_alloc_from_fd
qemu_ram_alloc_from_file
let's switch them to use the 'flags' parameters so as to ease future
flag additions.

The existing 'share' flag is converted to the RAM_SHARED bit in ram_flags,
and other flag bits are ignored by above functions right now.

Signed-off-by: Junyan He <junyan.he@intel.com>
Signed-off-by: Haozhong Zhang <haozhong.zhang@intel.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
2018-08-10 13:29:39 +03:00
Junyan He b0e5de9381 memory, exec: Expose all memory block related flags.
We need to use these flags in other files rather than just in exec.c,
For example, RAM_SHARED should be used when create a ram block from file.
We expose them the exec/memory.h

Signed-off-by: Junyan He <junyan.he@intel.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2018-08-10 13:29:39 +03:00
Paolo Bonzini c40d479207 tcg: simplify !CONFIG_TCG handling of tb_invalidate_*
There is no need for a stub, since tb_invalidate_phys_addr can be excised
altogether when TCG is disabled.  This is a bit cleaner since it avoids
using code that is clearly specific to user-mode emulation (it calls
mmap_lock/unlock) for the !CONFIG_TCG case.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-07-02 15:41:18 +02:00
Philippe Mathieu-Daudé 646f34fa54 tcg: Fix --disable-tcg build breakage
Fix the --disable-tcg breakage introduced by 8bca9a03ec60d:

    $ configure --disable-tcg
    [...]
    $ make -C i386-softmmu exec.o
    make: Entering directory 'i386-softmmu'
      CC      exec.o
    In file included from source/qemu/exec.c:62:0:
    source/qemu/include/exec/ram_addr.h:96:6: error: conflicting types for ‘tb_invalidate_phys_range’
     void tb_invalidate_phys_range(ram_addr_t start, ram_addr_t end);
          ^~~~~~~~~~~~~~~~~~~~~~~~
    In file included from source/qemu/exec.c:24:0:
    source/qemu/include/exec/exec-all.h:309:6: note: previous declaration of ‘tb_invalidate_phys_range’ was here
     void tb_invalidate_phys_range(target_ulong start, target_ulong end);
          ^~~~~~~~~~~~~~~~~~~~~~~~
    source/qemu/exec.c:1043:6: error: conflicting types for ‘tb_invalidate_phys_addr’
     void tb_invalidate_phys_addr(AddressSpace *as, hwaddr addr, MemTxAttrs attrs)
          ^~~~~~~~~~~~~~~~~~~~~~~
    In file included from source/qemu/exec.c:24:0:
    source/qemu/include/exec/exec-all.h:308:6: note: previous declaration of ‘tb_invalidate_phys_addr’ was here
     void tb_invalidate_phys_addr(target_ulong addr);
          ^~~~~~~~~~~~~~~~~~~~~~~
    make: *** [source/qemu/rules.mak:69: exec.o] Error 1
    make: Leaving directory 'i386-softmmu'

Tested to build x86_64-softmmu and i386-softmmu targets.

Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-id: 20180629200710.27626-1-f4bug@amsat.org
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2018-07-02 13:42:05 +01:00
David Hildenbrand 61362b71c1 exec: check that alignment is a power of two
Right now we can crash QEMU using e.g.

qemu-system-x86_64 -m 256M,maxmem=20G,slots=2 \
 -object memory-backend-file,id=mem0,size=12288,mem-path=/dev/zero,align=12288 \
 -device pc-dimm,id=dimm1,memdev=mem0

qemu-system-x86_64: util/mmap-alloc.c:115:
 qemu_ram_mmap: Assertion `is_power_of_2(align)' failed

Fix this by adding a proper check.

Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20180607154705.6316-3-david@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-06-28 19:05:31 +02:00
Paolo Bonzini 8bca9a03ec move public invalidate APIs out of translate-all.{c,h}, clean up
Place them in exec.c, exec-all.h and ram_addr.h.  This removes
knowledge of translate-all.h (which is an internal header) from
several files outside accel/tcg and removes knowledge of
AddressSpace from translate-all.c (as it only operates on ram_addr_t).

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-06-28 19:05:30 +02:00
Eric Auger a99761d3c8 exec: Fix MAP_RAM for cached access
When an IOMMUMemoryRegion is in front of a virtio device,
address_space_cache_init does not set cache->ptr as the memory
region is not RAM. However when the device performs an access,
we end up in glue() which performs the translation and then uses
MAP_RAM. This latter uses the unset ptr and returns a wrong value
which leads to a SIGSEV in address_space_lduw_internal_cached_slow,
for instance.

In slow path cache->ptr is NULL and MAP_RAM must redirect to
qemu_map_ram_ptr((mr)->ram_block, ofs).

As MAP_RAM, IS_DIRECT and INVALIDATE are the same in _cached_slow
and non cached mode, let's remove those macros.

This fixes the use cases featuring vIOMMU (Intel and ARM SMMU)
which lead to a SIGSEV.

Fixes: 48564041a7 (exec: reintroduce MemoryRegion caching)
Signed-off-by: Eric Auger <eric.auger@redhat.com>

Message-Id: <1528895946-28677-1-git-send-email-eric.auger@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-06-28 19:05:30 +02:00
David Hildenbrand c136180c90 postcopy: drop ram_pages parameter from postcopy_ram_incoming_init()
Not needed. Don't expose last_ram_page().

Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20180620202736.21399-1-david@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2018-06-27 13:28:31 +02:00
Emilio G. Cota f28d0dfdce tcg: fix --disable-tcg build breakage
Fix the --disable-tcg breakage introduced by tb_lock's removal by
relying on the fact that tcg_enabled() is set to 0 at
compile-time under --disable-tcg.

While at it, add further asserts to fix builds that enable both
--disable-tcg and --enable-debug, which were broken even before
tb_lock's removal.

Tested to build x86_64-softmmu and i386-softmmu targets.

Reported-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Emilio G. Cota <cota@braap.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2018-06-22 18:55:24 +01:00
Emilio G. Cota 0ac20318ce tcg: remove tb_lock
Use mmap_lock in user-mode to protect TCG state and the page descriptors.
In !user-mode, each vCPU has its own TCG state, so no locks needed.
Per-page locks are used to protect the page descriptors.

Per-TB locks are used in both modes to protect TB jumps.

Some notes:

- tb_lock is removed from notdirty_mem_write by passing a
  locked page_collection to tb_invalidate_phys_page_fast.

- tcg_tb_lookup/remove/insert/etc have their own internal lock(s),
  so there is no need to further serialize access to them.

- do_tb_flush is run in a safe async context, meaning no other
  vCPU threads are running. Therefore acquiring mmap_lock there
  is just to please tools such as thread sanitizer.

- Not visible in the diff, but tb_invalidate_phys_page already
  has an assert_memory_lock.

- cpu_io_recompile is !user-only, so no mmap_lock there.

- Added mmap_unlock()'s before all siglongjmp's that could
  be called in user-mode while mmap_lock is held.
  + Added an assert for !have_mmap_lock() after returning from
    the longjmp in cpu_exec, just like we do in cpu_exec_step_atomic.

Performance numbers before/after:

Host: AMD Opteron(tm) Processor 6376

                 ubuntu 17.04 ppc64 bootup+shutdown time

  700 +-+--+----+------+------------+-----------+------------*--+-+
      |    +    +      +            +           +           *B    |
      |         before ***B***                            ** *    |
      |tb lock removal ###D###                         ***        |
  600 +-+                                           ***         +-+
      |                                           **         #    |
      |                                        *B*          #D    |
      |                                     *** *         ##      |
  500 +-+                                ***           ###      +-+
      |                             * ***           ###           |
      |                            *B*          # ##              |
      |                          ** *          #D#                |
  400 +-+                      **            ##                 +-+
      |                      **           ###                     |
      |                    **           ##                        |
      |                  **         # ##                          |
  300 +-+  *           B*          #D#                          +-+
      |    B         ***        ###                               |
      |    *       **       ####                                  |
      |     *   ***      ###                                      |
  200 +-+   B  *B     #D#                                       +-+
      |     #B* *   ## #                                          |
      |     #*    ##                                              |
      |    + D##D#     +            +           +            +    |
  100 +-+--+----+------+------------+-----------+------------+--+-+
           1    8      16      Guest CPUs       48           64
  png: https://imgur.com/HwmBHXe

              debian jessie aarch64 bootup+shutdown time

  90 +-+--+-----+-----+------------+------------+------------+--+-+
     |    +     +     +            +            +            +    |
     |         before ***B***                                B    |
  80 +tb lock removal ###D###                              **D  +-+
     |                                                   **###    |
     |                                                 **##       |
  70 +-+                                             ** #       +-+
     |                                             ** ##          |
     |                                           **  #            |
  60 +-+                                       *B  ##           +-+
     |                                       **  ##               |
     |                                    ***  #D                 |
  50 +-+                               ***   ##                 +-+
     |                             * **   ###                     |
     |                           **B*  ###                        |
  40 +-+                     ****  # ##                         +-+
     |                   ****     #D#                             |
     |             ***B**      ###                                |
  30 +-+    B***B**        ####                                 +-+
     |    B *   *     # ###                                       |
     |     B       ###D#                                          |
  20 +-+   D  ##D##                                             +-+
     |      D#                                                    |
     |    +     +     +            +            +            +    |
  10 +-+--+-----+-----+------------+------------+------------+--+-+
          1     8     16      Guest CPUs        48           64
  png: https://imgur.com/iGpGFtv

The gains are high for 4-8 CPUs. Beyond that point, however, unrelated
lock contention significantly hurts scalability.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2018-06-15 08:18:48 -10:00
Peter Maydell 1f871c5e6b exec.c: Handle IOMMUs in address_space_translate_for_iotlb()
Currently we don't support board configurations that put an IOMMU
in the path of the CPU's memory transactions, and instead just
assert() if the memory region fonud in address_space_translate_for_iotlb()
is an IOMMUMemoryRegion.

Remove this limitation by having the function handle IOMMUs.
This is mostly straightforward, but we must make sure we have
a notifier registered for every IOMMU that a transaction has
passed through, so that we can flush the TLB appropriately
when any of the IOMMUs change their mappings.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-id: 20180604152941.20374-5-peter.maydell@linaro.org
2018-06-15 15:23:34 +01:00
Peter Maydell 2c91bcf273 iommu: Add IOMMU index argument to translate method
Add an IOMMU index argument to the translate method of
IOMMUs. Since all of our current IOMMU implementations
support only a single IOMMU index, this has no effect
on the behaviour.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-id: 20180604152941.20374-4-peter.maydell@linaro.org
2018-06-15 15:23:34 +01:00
Peter Maydell 6d3ede5410 exec.c: Use stn_p() and ldn_p() instead of explicit switches
Now we have stn_p() and ldn_p() we can use them in various
functions in exec.c that used to have their own switch-on-size code.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20180611171007.4165-4-peter.maydell@linaro.org
2018-06-15 15:23:34 +01:00
Peter Maydell 22672c6075 exec.c: Don't accidentally sign-extend 4-byte loads in subpage_read()
In subpage_read() we perform a load of the data into a local buffer
which we then access using ldub_p(), lduw_p(), ldl_p() or ldq_p()
depending on its size, storing the result into the uint64_t *data.
Since ldl_p() returns an 'int', this means that for the 4-byte
case we will sign-extend the data, whereas for 1 and 2 byte
reads we zero-extend it.

This ought not to matter since the caller will likely ignore values in
the high bytes of the data, but add a cast so that we're consistent.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20180611171007.4165-3-peter.maydell@linaro.org
2018-06-15 15:23:34 +01:00
Peter Maydell 2d54f19401 cputlb: Pass cpu_transaction_failed() the correct physaddr
The API for cpu_transaction_failed() says that it takes the physical
address for the failed transaction. However we were actually passing
it the offset within the target MemoryRegion. We don't currently
have any target CPU implementations of this hook that require the
physical address; fix this bug so we don't get confused if we ever
do add one.

Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20180611125633.32755-3-peter.maydell@linaro.org
2018-06-15 15:23:34 +01:00
Peter Maydell b74588a493 migration/next for 20180604
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Merge remote-tracking branch 'remotes/juanquintela/tags/migration/20180604' into staging

migration/next for 20180604

# gpg: Signature made Mon 04 Jun 2018 05:14:24 BST
# gpg:                using RSA key F487EF185872D723
# gpg: Good signature from "Juan Quintela <quintela@redhat.com>"
# gpg:                 aka "Juan Quintela <quintela@trasno.org>"
# Primary key fingerprint: 1899 FF8E DEBF 58CC EE03  4B82 F487 EF18 5872 D723

* remotes/juanquintela/tags/migration/20180604:
  migration: not wait RDMA_CM_EVENT_DISCONNECTED event after rdma_disconnect
  migration: remove unnecessary variables len in QIOChannelRDMA
  migration: Don't activate block devices if using -S
  migration: discard non-migratable RAMBlocks
  migration: introduce decompress-error-check

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2018-06-04 12:54:00 +01:00
Cédric Le Goater b895de5027 migration: discard non-migratable RAMBlocks
On the POWER9 processor, the XIVE interrupt controller can control
interrupt sources using MMIO to trigger events, to EOI or to turn off
the sources. Priority management and interrupt acknowledgment is also
controlled by MMIO in the presenter sub-engine.

These MMIO regions are exposed to guests in QEMU with a set of 'ram
device' memory mappings, similarly to VFIO, and the VMAs are populated
dynamically with the appropriate pages using a fault handler.

But, these regions are an issue for migration. We need to discard the
associated RAMBlocks from the RAM state on the source VM and let the
destination VM rebuild the memory mappings on the new host in the
post_load() operation just before resuming the system.

To achieve this goal, the following introduces a new RAMBlock flag
RAM_MIGRATABLE which is updated in the vmstate_register_ram() and
vmstate_unregister_ram() routines. This flag is then used by the
migration to identify RAMBlocks to discard on the source. Some checks
are also performed on the destination to make sure nothing invalid was
sent.

This change impacts the boston, malta and jazz mips boards for which
migration compatibility is broken.

Signed-off-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2018-06-04 05:46:15 +02:00
Peter Maydell afd76ffba9 * Linux header upgrade (Peter)
* firmware.json definition (Laszlo)
 * IPMI migration fix (Corey)
 * QOM improvements (Alexey, Philippe, me)
 * Memory API cleanups (Jay, me, Tristan, Peter)
 * WHPX fixes and improvements (Lucian)
 * Chardev fixes (Marc-André)
 * IOMMU documentation improvements (Peter)
 * Coverity fixes (Peter, Philippe)
 * Include cleanup (Philippe)
 * -clock deprecation (Thomas)
 * Disable -sandbox unless CONFIG_SECCOMP (Yi Min Zhao)
 * Configurability improvements (me)
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 -----END PGP SIGNATURE-----

Merge remote-tracking branch 'remotes/bonzini/tags/for-upstream' into staging

* Linux header upgrade (Peter)
* firmware.json definition (Laszlo)
* IPMI migration fix (Corey)
* QOM improvements (Alexey, Philippe, me)
* Memory API cleanups (Jay, me, Tristan, Peter)
* WHPX fixes and improvements (Lucian)
* Chardev fixes (Marc-André)
* IOMMU documentation improvements (Peter)
* Coverity fixes (Peter, Philippe)
* Include cleanup (Philippe)
* -clock deprecation (Thomas)
* Disable -sandbox unless CONFIG_SECCOMP (Yi Min Zhao)
* Configurability improvements (me)

# gpg: Signature made Fri 01 Jun 2018 17:42:13 BST
# gpg:                using RSA key BFFBD25F78C7AE83
# gpg: Good signature from "Paolo Bonzini <bonzini@gnu.org>"
# gpg:                 aka "Paolo Bonzini <pbonzini@redhat.com>"
# Primary key fingerprint: 46F5 9FBD 57D6 12E7 BFD4  E2F7 7E15 100C CD36 69B1
#      Subkey fingerprint: F133 3857 4B66 2389 866C  7682 BFFB D25F 78C7 AE83

* remotes/bonzini/tags/for-upstream: (56 commits)
  hw: make virtio devices configurable via default-configs/
  hw: allow compiling out SCSI
  memory: Make operations using MemoryRegionIoeventfd struct pass by pointer.
  char: Remove unwanted crlf conversion
  qdev: Remove DeviceClass::init() and ::exit()
  qdev: Simplify the SysBusDeviceClass::init path
  hw/i2c: Use DeviceClass::realize instead of I2CSlaveClass::init
  hw/i2c/smbus: Use DeviceClass::realize instead of SMBusDeviceClass::init
  target/i386/kvm.c: Remove compatibility shim for KVM_HINTS_REALTIME
  Update Linux headers to 4.17-rc6
  target/i386/kvm.c: Handle renaming of KVM_HINTS_DEDICATED
  scripts/update-linux-headers: Handle kernel license no longer being one file
  scripts/update-linux-headers: Handle __aligned_u64
  virtio-gpu-3d: Define VIRTIO_GPU_CAPSET_VIRGL2 elsewhere
  gdbstub: Prevent fd leakage
  docs/interop: add "firmware.json"
  ipmi: Use proper struct reference for KCS vmstate
  vmstate: Add a VSTRUCT type
  tcg: remove softfloat from --disable-tcg builds
  qemu-options: Mark the non-functional -clock option as deprecated
  ...

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2018-06-01 18:24:16 +01:00
Peter Maydell 8347c18506 exec.c: Initialize sa_flags passed to sigaction()
Coverity points out that in the user-only version of cpu_abort() we
call sigaction() with a partially initialized struct sigaction
(CID 1005351). Correct the omission.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-Id: <20180515182700.31736-1-peter.maydell@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-06-01 15:13:46 +02:00
Peter Maydell 2f7b009c2e Make address_space_translate_iommu take a MemTxAttrs argument
As part of plumbing MemTxAttrs down to the IOMMU translate method,
add MemTxAttrs as an argument to address_space_translate_iommu().

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20180521140402.23318-14-peter.maydell@linaro.org
2018-05-31 16:32:35 +01:00
Peter Maydell 49e14aa827 Make flatview_do_translate() take a MemTxAttrs argument
As part of plumbing MemTxAttrs down to the IOMMU translate method,
add MemTxAttrs as an argument to flatview_do_translate().

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20180521140402.23318-13-peter.maydell@linaro.org
2018-05-31 16:32:35 +01:00
Peter Maydell 7446eb07c1 Make address_space_get_iotlb_entry() take a MemTxAttrs argument
As part of plumbing MemTxAttrs down to the IOMMU translate method,
add MemTxAttrs as an argument to address_space_get_iotlb_entry().

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20180521140402.23318-12-peter.maydell@linaro.org
2018-05-31 16:32:35 +01:00
Peter Maydell efa99a2ff8 Make flatview_translate() take a MemTxAttrs argument
As part of plumbing MemTxAttrs down to the IOMMU translate method,
add MemTxAttrs as an argument to flatview_translate(); all its
callers now have attrs available.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20180521140402.23318-11-peter.maydell@linaro.org
2018-05-31 16:32:35 +01:00
Peter Maydell eace72b7a6 Make flatview_access_valid() take a MemTxAttrs argument
As part of plumbing MemTxAttrs down to the IOMMU translate method,
add MemTxAttrs as an argument to flatview_access_valid().
Its callers now all have an attrs value to hand, so we can
correct our earlier temporary use of MEMTXATTRS_UNSPECIFIED.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20180521140402.23318-10-peter.maydell@linaro.org
2018-05-31 16:32:35 +01:00
Peter Maydell 8372d38327 Make MemoryRegion valid.accepts callback take a MemTxAttrs argument
As part of plumbing MemTxAttrs down to the IOMMU translate method,
add MemTxAttrs as an argument to the MemoryRegion valid.accepts
callback. We'll need this for subpage_accepts().

We could take the approach we used with the read and write
callbacks and add new a new _with_attrs version, but since there
are so few implementations of the accepts hook we just change
them all.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20180521140402.23318-9-peter.maydell@linaro.org
2018-05-31 16:32:35 +01:00
Peter Maydell 6d7b9a6c3b Make memory_region_access_valid() take a MemTxAttrs argument
As part of plumbing MemTxAttrs down to the IOMMU translate method,
add MemTxAttrs as an argument to memory_region_access_valid().
Its callers either have an attrs value to hand, or don't care
and can use MEMTXATTRS_UNSPECIFIED.

The callsite in flatview_access_valid() is part of a recursive
loop flatview_access_valid() -> memory_region_access_valid() ->
 subpage_accepts() -> flatview_access_valid(); we make it pass
MEMTXATTRS_UNSPECIFIED for now, until the next several commits
have plumbed an attrs parameter through the rest of the loop
and we can add an attrs parameter to flatview_access_valid().

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20180521140402.23318-8-peter.maydell@linaro.org
2018-05-31 16:32:35 +01:00
Peter Maydell 53d0790dfe Make flatview_extend_translation() take a MemTxAttrs argument
As part of plumbing MemTxAttrs down to the IOMMU translate method,
add MemTxAttrs as an argument to flatview_extend_translation().
Its callers either have an attrs value to hand, or don't care
and can use MEMTXATTRS_UNSPECIFIED.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20180521140402.23318-7-peter.maydell@linaro.org
2018-05-31 16:32:35 +01:00
Peter Maydell fddffa4268 Make address_space_access_valid() take a MemTxAttrs argument
As part of plumbing MemTxAttrs down to the IOMMU translate method,
add MemTxAttrs as an argument to address_space_access_valid().
Its callers either have an attrs value to hand, or don't care
and can use MEMTXATTRS_UNSPECIFIED.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20180521140402.23318-6-peter.maydell@linaro.org
2018-05-31 16:32:35 +01:00
Peter Maydell f26404fbee Make address_space_map() take a MemTxAttrs argument
As part of plumbing MemTxAttrs down to the IOMMU translate method,
add MemTxAttrs as an argument to address_space_map().
Its callers either have an attrs value to hand, or don't care
and can use MEMTXATTRS_UNSPECIFIED.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20180521140402.23318-5-peter.maydell@linaro.org
2018-05-31 16:32:35 +01:00
Peter Maydell bc6b1cec84 Make address_space_translate{, _cached}() take a MemTxAttrs argument
As part of plumbing MemTxAttrs down to the IOMMU translate method,
add MemTxAttrs as an argument to address_space_translate()
and address_space_translate_cached(). Callers either have an
attrs value to hand, or don't care and can use MEMTXATTRS_UNSPECIFIED.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20180521140402.23318-4-peter.maydell@linaro.org
2018-05-31 14:50:52 +01:00
Peter Maydell c874dc4f5e Make tb_invalidate_phys_addr() take a MemTxAttrs argument
As part of plumbing MemTxAttrs down to the IOMMU translate method,
add MemTxAttrs as an argument to tb_invalidate_phys_addr().
Its callers either have an attrs value to hand, or don't care
and can use MEMTXATTRS_UNSPECIFIED.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-id: 20180521140402.23318-3-peter.maydell@linaro.org
2018-05-31 14:50:52 +01:00
Paolo Bonzini 48564041a7 exec: reintroduce MemoryRegion caching
MemoryRegionCache was reverted to "normal" address_space_* operations
for 2.9, due to lack of support for IOMMUs.  Reinstate the
optimizations, caching only the IOMMU translation at address_cache_init
but not the IOMMU lookup and target AddressSpace translation are not
cached; now that MemoryRegionCache supports IOMMUs, it becomes more widely
applicable too.

The inlined fast path is defined in memory_ldst_cached.inc.h, while the
slow path uses memory_ldst.inc.c as before.  The smaller fast path causes
a little code size reduction in MemoryRegionCache users:

    hw/virtio/virtio.o text size before: 32373
    hw/virtio/virtio.o text size after: 31941

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-05-09 00:13:38 +02:00
Paolo Bonzini a411c84b56 exec: extract address_space_translate_iommu, fix page_mask corner case
This will be used to process IOMMUs in a MemoryRegionCache.  This
includes a small bugfix, in that the returned page_mask is now
correctly -1 if the IOMMU memory region maps the entire address
space directly.  Previously, address_space_get_iotlb_entry would
return ~TARGET_PAGE_MASK.

Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-05-09 00:13:38 +02:00
Paolo Bonzini ad2804d9e4 exec: small changes to flatview_do_translate
Prepare for extracting the IOMMU part to a separate function.  Mostly
cosmetic; the only semantic change is that, if there is more than one
cascaded IOMMU and the second one fails to translate, *plen_out is now
adjusted according to the page mask of the first IOMMU.

Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-05-09 00:13:38 +02:00
David Gibson 2b10808539 Add host_memory_backend_pagesize() helper
There are a couple places (one generic, one target specific) where we need
to get the host page size associated with a particular memory backend.  I
have some upcoming code which will add another place which wants this.  So,
for convenience, add a helper function to calculate this.

host_memory_backend_pagesize() returns the host pagesize for a given
HostMemoryBackend object.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Greg Kurz <groug@kaod.org>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
2018-04-27 18:05:22 +10:00