Commit Graph
797 Commits
Author SHA1 Message Date
Paolo Bonzini e4a511f8cc exec: clamp accesses against the MemoryRegionSection
Because the clamping was done against the MemoryRegion,
address_space_rw was effectively broken if a write spanned
multiple sections that are not linear in underlying memory
(with the memory not being under an IOMMU).

This is visible with the MIPS rc4030 IOMMU, which is implemented
as a series of alias memory regions that point to the actual RAM.

Tested-by: Hervé Poussineau <hpoussin@reactos.org>
Tested-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-06-19 12:27:14 +02:00
Paolo Bonzini 965eb2fcdf exec: do not clamp accesses to MMIO regions
It is common for MMIO registers to overlap, for example a 4 byte register
at 0xcf8 (totally random choice... :)) and a 1 byte register at 0xcf9.
If these registers are implemented via separate MemoryRegions, it is
wrong to clamp the accesses as the value written would be truncated.

Hence for these regions the effects of commit 23820db (exec: Respect
as_translate_internal length clamp, 2015-03-16, previously applied as
commit c3c1bb99) must be skipped.

Tested-by: Hervé Poussineau <hpoussin@reactos.org>
Tested-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-06-19 12:27:14 +02:00
Dr. David Alan GilbertandJuan Quintela e3807054e2 qemu_ram_foreach_block: pass up error value, and down the ramblock name
check the return value of the function it calls and error if it's non-0
Fixup qemu_rdma_init_one_block that is the only current caller,
  and rdma_add_block the only function it calls using it.

Pass the name of the ramblock to the function; helps in debugging.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Amit Shah <amit.shah@redhat.com>
Reviewed-by: Michael R. Hines <mrhines@us.ibm.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2015-06-12 06:54:01 +02:00
Juan Quintela 5cd8cadae8 migration: Use normal VMStateDescriptions for Subsections
We create optional sections with this patch.  But we already have
optional subsections.  Instead of having two mechanism that do the
same, we can just generalize it.

For subsections we just change:

- Add a needed function to VMStateDescription
- Remove VMStateSubsection (after removal of the needed function
  it is just a VMStateDescription)
- Adjust the whole tree, moving the needed function to the corresponding
  VMStateDescription

Signed-off-by: Juan Quintela <quintela@redhat.com>
2015-06-12 06:53:57 +02:00
Stefan HajnocziandPaolo Bonzini 03eebc9e32 memory: replace cpu_physical_memory_reset_dirty() with test-and-clear
The cpu_physical_memory_reset_dirty() function is sometimes used
together with cpu_physical_memory_get_dirty().  This is not atomic since
two separate accesses to the dirty memory bitmap are made.

Turn cpu_physical_memory_reset_dirty() and
cpu_physical_memory_clear_dirty_range_type() into the atomic
cpu_physical_memory_test_and_clear_dirty().

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <1417519399-3166-6-git-send-email-stefanha@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-06-05 17:10:00 +02:00
Paolo Bonzini e87f7778b6 exec: only check relevant bitmaps for cleanliness
Most of the time, not all bitmaps have to be marked as dirty;
do not do anything if the interesting ones are already dirty.
Previously, any clean bitmap would have cause all the bitmaps to be
marked dirty.

In fact, unless running TCG most of the time bitmap operations need
not be done at all, because memory_region_is_logging returns zero.
In this case, skip the call to cpu_physical_memory_range_includes_clean
altogether as well.

With this patch, cpu_physical_memory_set_dirty_range is called
unconditionally, so there need not be anymore a separate call to
xen_modified_memory.

Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-06-05 17:10:00 +02:00
Paolo Bonzini 58d2707e87 exec: pass client mask to cpu_physical_memory_set_dirty_range
This cuts in half the cost of bitmap operations (which will become more
expensive when made atomic) during migration on non-VRAM regions.

Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-06-05 17:09:59 +02:00
Paolo Bonzini 358653391b translate-all: remove unnecessary argument to tb_invalidate_phys_range
The is_cpu_write_access argument is always 0, remove it.

Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-06-05 17:09:59 +02:00
Paolo Bonzini 845b6214a3 exec: use memory_region_get_dirty_log_mask to optimize dirty tracking
The memory API can now return the exact set of bitmaps that have to
be tracked.  Use it instead of the in_migration variable.

In the next patches, we will also use it to set only DIRTY_MEMORY_VGA
or DIRTY_MEMORY_MIGRATION if necessary.  This can make a difference
for dataplane, especially after the dirty bitmap is changed to use
more expensive atomic operations.

Of some interest is the change to stl_phys_notdirty.  When migration
was introduced, stl_phys_notdirty was changed to effectively behave
as stl_phys during migration.  In fact, if one looks at the function as it
was in the beginning (commit 8df1cd0, physical memory access functions,
2005-01-28), at the time the dirty bitmap was the equivalent of
DIRTY_MEMORY_CODE nowadays; hence, the function simply should not touch
the dirty code bits.  This patch changes it to do the intended thing.

Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-06-05 17:09:59 +02:00
Paolo Bonzini 49dfcec403 ram_addr: tweaks to xen_modified_memory
Invoke xen_modified_memory from cpu_physical_memory_set_dirty_range_nocode;
it is akin to DIRTY_MEMORY_MIGRATION, so set it together with that bitmap.
The remaining call from invalidate_and_set_dirty's "else" branch will go
away soon.

Second, fix the second argument to the function in the
cpu_physical_memory_set_dirty_lebitmap call site.  That function is only used
by KVM, but it is better to be clean anyway.

Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-06-05 17:09:59 +02:00
Paolo Bonzini db94604b20 exec: optimize phys_page_set_level
phys_page_set_level is writing zeroes to a struct that has just been
filled in by phys_map_node_alloc.  Instead, tell phys_map_node_alloc
whether to fill in the page "as a leaf" or "as a non-leaf".

memcpy is faster than struct assignment, which copies each bitfield
individually.  A compiler bug (https://gcc.gnu.org/PR66391), and
small memcpys like this one are special-cased anyway, and optimized
to a register move, so just use the memcpy.

This cuts the cost of phys_page_set_level from 25% to 5% when
booting qboot.

Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-06-05 17:09:58 +02:00
Paolo Bonzini 41063e1e7a exec: move rcu_read_lock/unlock to address_space_translate callers
Once address_space_translate will be called outside the BQL, the returned
MemoryRegion might disappear as soon as the RCU read-side critical section
ends.  Avoid this by moving the critical section to the callers.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <1426684909-95030-3-git-send-email-pbonzini@redhat.com>
2015-04-30 16:55:32 +02:00
Peter Maydell 06feaacfb4 Merge remote-tracking branch 'remotes/bonzini/tags/for-upstream' into staging
- miscellaneous cleanups for TCG (Emilio) and NBD (Bogdan)
- next part in the thread-safe address_space_* saga: atomic access
  to the bounce buffer and the map_clients list, from Fam
- optional support for linking with tcmalloc, also from Fam
- reapplying Peter Crosthwaite's "Respect as_translate_internal
  length clamp" after fixing the SPARC fallout.
- build system fix from Wei Liu
- small acpi-build and ioport cleanup by myself

# gpg: Signature made Wed Apr 29 09:34:00 2015 BST using RSA key ID 78C7AE83
# gpg: Good signature from "Paolo Bonzini <bonzini@gnu.org>"
# gpg:                 aka "Paolo Bonzini <pbonzini@redhat.com>"
# gpg: WARNING: This key is not certified with sufficiently trusted signatures!
# gpg:          It is not certain that the signature belongs to the owner.
# 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: (22 commits)
  nbd/trivial: fix type cast for ioctl
  translate-all: use bitmap helpers for PageDesc's bitmap
  target-i386: disable LINT0 after reset
  Makefile.target: prepend $libs_softmmu to $LIBS
  milkymist: do not modify libs-softmmu
  configure: Add support for tcmalloc
  exec: Respect as_translate_internal length clamp
  ioport: reserve the whole range of an I/O port in the AddressSpace
  ioport: loosen assertions on emulation of 16-bit ports
  ioport: remove wrong comment
  ide: there is only one data port
  gus: clean up MemoryRegionPortio
  sb16: remove useless mixer_write_indexw
  sun4m: fix slavio sysctrl and led register sizes
  acpi-build: remove dependency from ram_addr.h
  memory: add memory_region_ram_resize
  dma-helpers: Fix race condition of continue_after_map_failure and dma_aio_cancel
  exec: Notify cpu_register_map_client caller if the bounce buffer is available
  exec: Protect map_client_list with mutex
  linux-user, bsd-user: Remove two calls to cpu_exec_init_all
  ...

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2015-04-30 12:04:11 +01:00
Peter CrosthwaiteandPaolo Bonzini 23820dbfc7 exec: Respect as_translate_internal length clamp
address_space_translate_internal will clamp the *plen length argument
based on the size of the memory region being queried. The iommu walker
logic in addresss_space_translate was ignoring this by discarding the
post fn call value of *plen. Fix by just always using *plen as the
length argument throughout the fn, removing the len local variable.

This fixes a bootloader bug when a single elf section spans multiple
QEMU memory regions.

Signed-off-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Message-Id: <1426570554-15940-1-git-send-email-peter.crosthwaite@xilinx.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-04-27 18:24:19 +02:00
Fam ZhengandPaolo Bonzini e95205e1f9 dma-helpers: Fix race condition of continue_after_map_failure and dma_aio_cancel
If DMA's owning thread cancels the IO while the bounce buffer's owning thread
is notifying the "cpu client list", a use-after-free happens:

     continue_after_map_failure               dma_aio_cancel
     ------------------------------------------------------------------
     aio_bh_new
                                              qemu_bh_delete
     qemu_bh_schedule (use after free)

Also, the old code doesn't run the bh in the right AioContext.

Fix both problems by passing a QEMUBH to cpu_register_map_client.

Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <1426496617-10702-6-git-send-email-famz@redhat.com>
[Remove unnecessary forward declaration. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-04-27 18:24:18 +02:00
Fam ZhengandPaolo Bonzini 33b6c2edf6 exec: Notify cpu_register_map_client caller if the bounce buffer is available
The caller's workflow is like

    if (!address_space_map()) {
        ...
        cpu_register_map_client();
    }

If bounce buffer became available after address_space_map() but before
cpu_register_map_client(), the caller could miss it and has to wait for the
next bounce buffer notify, which may never happen in the worse case.

Just notify the list in cpu_register_map_client().

Signed-off-by: Fam Zheng <famz@redhat.com>
Message-Id: <1426496617-10702-5-git-send-email-famz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-04-27 18:24:18 +02:00
Fam ZhengandPaolo Bonzini 38e047b50d exec: Protect map_client_list with mutex
So that accesses from multiple threads are safe.

Signed-off-by: Fam Zheng <famz@redhat.com>
Message-Id: <1426496617-10702-4-git-send-email-famz@redhat.com>
[Remove #if from cpu_exec_init_all. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-04-27 18:24:17 +02:00
Fam ZhengandPaolo Bonzini c2cba0ffe4 exec: Atomic access to bounce buffer
There could be a race condition when two processes call
address_space_map concurrently and both want to use the bounce buffer.

Add an in_use flag in BounceBuffer to sync it.

Signed-off-by: Fam Zheng <famz@redhat.com>
Message-Id: <1426496617-10702-2-git-send-email-famz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-04-27 18:24:17 +02:00
Peter Maydell 66b9b43c42 exec.c: Capture the memory attributes for a watchpoint hit
Capture the memory attributes for the transaction which triggered
a watchpoint; this allows CPU specific code to implement features
like ARM's "user-mode only WPs also hit for LDRT/STRT accesses
made from privileged code". This change also correctly passes
through the memory attributes to the underlying device when
a watchpoint access doesn't hit.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
2015-04-26 16:49:24 +01:00
Peter Maydell 500131154d exec.c: Add new address_space_ld*/st* functions
Add new address_space_ld*/st* functions which allow transaction
attributes and error reporting for basic load and stores. These
are named to be in line with the address_space_read/write/rw
buffer operations.

The existing ld/st*_phys functions are now wrappers around
the new functions.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
2015-04-26 16:49:24 +01:00
Peter Maydell 5c9eb0286c exec.c: Make address_space_rw take transaction attributes
Make address_space_rw take transaction attributes, rather
than always using the 'unspecified' attributes.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
2015-04-26 16:49:24 +01:00
Peter Maydell f25a49e005 exec.c: Convert subpage memory ops to _with_attrs
Convert the subpage memory ops to _with_attrs; this will allow
us to pass the attributes through to the underlying access
functions. (Nothing uses the attributes yet.)

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
2015-04-26 16:49:24 +01:00
Peter Maydell 3b64349539 memory: Replace io_mem_read/write with memory_region_dispatch_read/write
Rather than retaining io_mem_read/write as simple wrappers around
the memory_region_dispatch_read/write functions, make the latter
public and change all the callers to use them, since we need to
touch all the callsites anyway to add MemTxAttrs and MemTxResult
support. Delete io_mem_read and io_mem_write entirely.

(All the callers currently pass MEMTXATTRS_UNSPECIFIED
and convert the return value back to bool or ignore it.)

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
2015-04-26 16:49:23 +01:00
Paolo Bonzini 4025446f0a Revert "exec: Respect as_tranlsate_internal length clamp"
This reverts commit c3c1bb99d1.
It causes problems with boards that declare memory regions shorter
than the registers they contain.

Reported-by: Zoltan Balaton <balaton@eik.bme.hu>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-04-01 10:06:38 +02:00
Paolo Bonzini f18c69cfc5 exec: avoid possible overwriting of mmaped area in qemu_ram_remap
It is not necessary to munmap an area before remapping it with MAP_FIXED;
if the memory region specified by addr and len overlaps pages of any
existing mapping, then the overlapped part of the existing mapping will
be discarded.

On the other hand, if QEMU does munmap the pages, there is a small
probability that another mmap sneaks in and catches the just-freed
portion of the address space.  In effect, munmap followed by
mmap(MAP_FIXED) is a use-after-free error, and Coverity flags it
as such.  Fix it.

Reviewed-by: Gonglei <arei.gonglei@huawei.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-03-26 10:43:54 +01:00