From 73034e9e087aa51b85cf86b6c81ef92f7e1e9d09 Mon Sep 17 00:00:00 2001 From: Paolo Bonzini Date: Tue, 7 May 2013 15:48:28 +0200 Subject: [PATCH] memory: allow memory_region_find() to run on non-root memory regions memory_region_find() is similar to registering a MemoryListener and checking for the MemoryRegionSections that come from a particular region. There is no reason for this to be limited to a root memory region. Reviewed-by: Peter Maydell Signed-off-by: Paolo Bonzini --- include/exec/memory.h | 28 +++++++++++++++++++--------- memory.c | 20 +++++++++++++++----- 2 files changed, 34 insertions(+), 14 deletions(-) diff --git a/include/exec/memory.h b/include/exec/memory.h index 9e88320113..329ffb191d 100644 --- a/include/exec/memory.h +++ b/include/exec/memory.h @@ -718,24 +718,34 @@ void memory_region_set_alias_offset(MemoryRegion *mr, hwaddr offset); /** - * memory_region_find: locate a MemoryRegion in an address space + * memory_region_find: translate an address/size relative to a + * MemoryRegion into a #MemoryRegionSection. * - * Locates the first #MemoryRegion within an address space given by - * @address_space that overlaps the range given by @addr and @size. + * Locates the first #MemoryRegion within @mr that overlaps the range + * given by @addr and @size. * * Returns a #MemoryRegionSection that describes a contiguous overlap. * It will have the following characteristics: - * .@offset_within_address_space >= @addr - * .@offset_within_address_space + .@size <= @addr + @size * .@size = 0 iff no overlap was found * .@mr is non-%NULL iff an overlap was found * - * @address_space: a top-level (i.e. parentless) region that contains - * the region to be found - * @addr: start of the area within @address_space to be searched + * Remember that in the return value the @offset_within_region is + * relative to the returned region (in the .@mr field), not to the + * @mr argument. + * + * Similarly, the .@offset_within_address_space is relative to the + * address space that contains both regions, the passed and the + * returned one. However, in the special case where the @mr argument + * has no parent (and thus is the root of the address space), the + * following will hold: + * .@offset_within_address_space >= @addr + * .@offset_within_address_space + .@size <= @addr + @size + * + * @mr: a MemoryRegion within which @addr is a relative address + * @addr: start of the area within @as to be searched * @size: size of the area to be searched */ -MemoryRegionSection memory_region_find(MemoryRegion *address_space, +MemoryRegionSection memory_region_find(MemoryRegion *mr, hwaddr addr, uint64_t size); /** diff --git a/memory.c b/memory.c index 75ca281e97..34bfb13894 100644 --- a/memory.c +++ b/memory.c @@ -1451,15 +1451,24 @@ static FlatRange *address_space_lookup(AddressSpace *as, AddrRange addr) sizeof(FlatRange), cmp_flatrange_addr); } -MemoryRegionSection memory_region_find(MemoryRegion *address_space, +MemoryRegionSection memory_region_find(MemoryRegion *mr, hwaddr addr, uint64_t size) { - AddressSpace *as = memory_region_to_address_space(address_space); - AddrRange range = addrrange_make(int128_make64(addr), - int128_make64(size)); - FlatRange *fr = address_space_lookup(as, range); MemoryRegionSection ret = { .mr = NULL, .size = 0 }; + MemoryRegion *root; + AddressSpace *as; + AddrRange range; + FlatRange *fr; + addr += mr->addr; + for (root = mr; root->parent; ) { + root = root->parent; + addr += root->addr; + } + + as = memory_region_to_address_space(root); + range = addrrange_make(int128_make64(addr), int128_make64(size)); + fr = address_space_lookup(as, range); if (!fr) { return ret; } @@ -1470,6 +1479,7 @@ MemoryRegionSection memory_region_find(MemoryRegion *address_space, } ret.mr = fr->mr; + ret.address_space = as; range = addrrange_intersection(range, fr->addr); ret.offset_within_region = fr->offset_in_region; ret.offset_within_region += int128_get64(int128_sub(range.start,