On Tue, Jan 22, 2019 at 04:36:36PM +0000, Peter Maydell wrote:
> On Sun, 20 Jan 2019 at 14:35, Stefan Hajnoczi <stefa...@redhat.com> wrote:
> >
> > 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 <stefa...@redhat.com>
> > ---
> > include/exec/memory.h | 18 ++++++++++++++++++
> > exec.c | 12 ++++++++++++
> > 2 files changed, 30 insertions(+)
> >
> > diff --git a/include/exec/memory.h b/include/exec/memory.h
> > index cd2f209b64..abe9cc79c0 100644
> > --- a/include/exec/memory.h
> > +++ b/include/exec/memory.h
> > @@ -1344,6 +1344,24 @@ bool memory_region_snapshot_get_dirty(MemoryRegion
> > *mr,
> > void memory_region_reset_dirty(MemoryRegion *mr, hwaddr addr,
> > hwaddr size, unsigned client);
> >
> > +/**
> > + * memory_region_flush_rom_device: Mark a range of pages dirty and
> > invalidate
> > + * TBs (for self-modifying code).
> > + *
> > + * The MemoryRegionOps->write() callback of a ROM device must use this
> > function
> > + * to mark byte ranges that have been modified internally, such as by
> > directly
> > + * accessing the memory returned by memory_region_get_ram_ptr().
> > + *
> > + * This function marks the range dirty and invalidates TBs so that TCG can
> > + * detect self-modifying code.
> > + *
> > + * @mr: the region being flushed.
> > + * @addr: the start, relative to the start of the region, of the range
> > being
> > + * flushed.
> > + * @size: the size, in bytes, of the range being flushed.
> > + */
> > +void memory_region_flush_rom_device(MemoryRegion *mr, hwaddr addr, hwaddr
> > size);
> > +
> > /**
> > * memory_region_set_readonly: Turn a memory region read-only (or
> > read-write)
> > *
> > diff --git a/exec.c b/exec.c
> > index 895449f926..105ff21e74 100644
> > --- a/exec.c
> > +++ b/exec.c
> > @@ -3162,6 +3162,18 @@ static void invalidate_and_set_dirty(MemoryRegion
> > *mr, hwaddr addr,
> > cpu_physical_memory_set_dirty_range(addr, length, dirty_log_mask);
> > }
> >
> > +void memory_region_flush_rom_device(MemoryRegion *mr, hwaddr addr, hwaddr
> > size)
> > +{
> > + /* In principle this function would work on other memory region types
> > too,
> > + * but the ROM device use case is the only one where this operation is
> > + * necessary. Other memory regions should use the
> > + * address_space_read/write() APIs.
> > + */
> > + assert(memory_region_is_romd(mr));
> > +
> > + invalidate_and_set_dirty(mr, addr, size);
> > +}
> > +
> > static int memory_access_size(MemoryRegion *mr, unsigned l, hwaddr addr)
> > {
> > unsigned access_size_max = mr->ops->valid.max_access_size;
>
> API and implementation make sense to me, but better that Paolo reviews
> this I think. I guess we should add calls to this to the pflash device
> models too...Okay, will cover pflash in the next revision. Stefan
signature.asc
Description: PGP signature
