memcpy can take a large amount of time for small reads and writes.
Handle the common case of reading s/g descriptors from memory (there
is no corresponding "write" case that is as common, because writes
often use address_space_st* functions) by inlining the relevant
parts of address_space_read into the caller.
Backports commit 3cc8f884996584630734a90c9b3c535af81e3c92 from qemu
Replace qemu_ram_free_from_ptr() with qemu_ram_free().
The only difference between qemu_ram_free_from_ptr() and
qemu_ram_free() is that g_free_rcu() is used instead of
call_rcu(reclaim_ramblock). We can safely replace it because:
* RAM blocks allocated by qemu_ram_alloc_from_ptr() always have
RAM_PREALLOC set;
* reclaim_ramblock(block) will do nothing except g_free(block)
if RAM_PREALLOC is set at block->flags.
Backports commit a29ac16632aec6065c72985b9f7eeb1ca6fbef4a from qemu
This makes ROM blocks resizeable. This infrastructure is required for other
functionality we have queued.
Backports commit aaf03019175949eda5087329448b8a0033b89479 from qemu
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().
Backports commit 03eebc9e3246b9b3f5925aa41f7dfd7c1e467875 from qemu
Use set_bit_atomic() and bitmap_set_atomic() so that multiple threads
can dirty memory without race conditions.
Backports commit d114875b9a1c21162f69a12d72f69a22e7bab376 from qemu
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.
Backports commit e87f7778b64d4a6a78e16c288c7fdc6c15317d5f from qemu
cpu_physical_memory_set_dirty_lebitmap unconditionally syncs the
DIRTY_MEMORY_CODE bitmap. This however is unused unless TCG is
enabled.
Backports commit 9460dee4b2258e3990906fb34099481c8334c267 from qemu
While it is obvious that cpu_physical_memory_get_dirty returns true even if
a single page is dirty, the same is not true for cpu_physical_memory_get_clean;
one would expect that it returns true only if all the pages are clean, but
it actually looks for even one clean page. (By contrast, the caller of that
function, cpu_physical_memory_range_includes_clean, has a good name).
To clarify, rename the function to cpu_physical_memory_all_dirty and return
true if _all_ the pages are dirty. This is the opposite of the previous
meaning, because "all are 1" is the same as "not (any is 0)", so we have to
modify cpu_physical_memory_range_includes_clean as well
Backports commit 72b47e79cef36ed6ffc718f10e21001d7ec2a66f from qemu