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.)
Backports commit 3b6434953934e6d4a776ed426d8c6d6badee176f from qemu
Define an API so that devices can register MemoryRegionOps whose read
and write callback functions are passed an arbitrary pointer to some
transaction attributes and can return a success-or-failure status code.
This will allow us to model devices which:
* behave differently for ARM Secure/NonSecure memory accesses
* behave differently for privileged/unprivileged accesses
* may return a transaction failure (causing a guest exception)
for erroneous accesses
This patch defines the new API and plumbs the attributes parameter through
to the memory.c public level functions io_mem_read() and io_mem_write(),
where it is currently dummied out.
The success/failure response indication is also propagated out to
io_mem_read() and io_mem_write(), which retain the old-style
boolean true-for-error return.
Backports commit cc05c43ad942165ecc6ffd39e41991bee43af044 from qemu
This commit fixes the following issues:
- Any unmapped/free'd memory regions (MemoryRegion instances) are not
removed from the object property linked list of its owner (which is
always qdev_get_machine(uc)). This issue makes adding new memory
mapping by calling mem_map() or mem_map_ptr() slower as more and more
memory pages are mapped and unmapped - yes, even if those memory pages
are unmapped, they still impact the speed of future memory page
mappings due to this issue.
- FlatView is not reconstructed after a memory region is freed during
unmapping, which leads to a use-after-free the next time a new memory
region is mapped in address_space_update_topology().
ARM and probably the rest of the arches have significant memory leaks as
they have no release interface.
Additionally, DrMemory does not have 64-bit support and thus I can't
test the 64-bit version under Windows. Under Linux valgrind supports
both 32-bit and 64-bit but there are different macros and code for Linux
and Windows.
It appears the problem is that we are not calling the memory region
destructor. After modifying memory_unmap to include the destructor call
for the memory region, the memory is freed.
Furthermore in uc_close we must explicitly free any blocks that were not
unmapped by the user to prevent leaks.
This should fix issue 305.
