Rust side will based on MemoryRegionSection to origanize non-overlapping memory "region" abstractions. So it's necessary to provide a translation variant helper to return the MemoryRegionSection directly.
Additionally, refine and complete the documentations for translation helpers. Signed-off-by: Zhao Liu <[email protected]> --- include/system/memory.h | 68 +++++++++++++++++++++++++++++++++++------ system/physmem.c | 22 ++++++++++--- 2 files changed, 77 insertions(+), 13 deletions(-) diff --git a/include/system/memory.h b/include/system/memory.h index f492e1fc78bf..eab69e15e10f 100644 --- a/include/system/memory.h +++ b/include/system/memory.h @@ -3053,24 +3053,74 @@ void address_space_cache_destroy(MemoryRegionCache *cache); IOMMUTLBEntry address_space_get_iotlb_entry(AddressSpace *as, hwaddr addr, bool is_write, MemTxAttrs attrs); -/* address_space_translate: translate an address range into an address space - * into a MemoryRegion and an address range into that section. Should be +/** + * flatview_translate_section: translate an guest physical address range + * to the corresponding MemoryRegionSection in Flatview. Should be * called from an RCU critical section, to avoid that the last reference - * to the returned region disappears after address_space_translate returns. - * - * @fv: #FlatView to be accessed - * @addr: address within that address space - * @xlat: pointer to address within the returned memory region section's - * #MemoryRegion. - * @len: pointer to length + * to the memory region (pointed by returned section) disappears after + * flatview_translate_section returns. + * + * @fv: the flat view to be accessed. + * @addr: the address to be translated in above address space. + * @xlat: the translated address offset within the returned section's + * #MemoryRegion. + * @len: pointer to length, and it will be changed to valid read/write + * length of the translated address after this function returns. * @is_write: indicates the transfer direction * @attrs: memory attributes + * + * Returns: + * The #MemoryRegionSection that contains the translated address + */ +MemoryRegionSection *flatview_translate_section(FlatView *fv, hwaddr addr, + hwaddr *xlat, hwaddr *len, + bool is_write, MemTxAttrs attrs); + +/** + * flatview_translate: translate an guest physical address range + * to the corresponding MemoryRegionSection in Flatview. Should be + * called from an RCU critical section, to avoid that the last reference + * to the returned memory region disappears after flatview_translate + * returns. + * + * This function is the variant of flatview_translate_section(), with the + * difference that it returns the MemoryRegion contained in the + * MemoryRegionSection. + * + * @fv: the flat view to be accessed. + * @addr: the address to be translated in above address space. + * @xlat: the translated address offset within memory region. + * @len: pointer to length, and it will be changed to valid read/write + * length of the translated address after this function returns. + * @is_write: whether the translation operation is for write. + * @attrs: memory transaction attributes. + * + * Returns: + * The #MemoryRegion that contains the translated address. */ MemoryRegion *flatview_translate(FlatView *fv, hwaddr addr, hwaddr *xlat, hwaddr *len, bool is_write, MemTxAttrs attrs); +/** + * address_space_translate: translate an guest physical address range + * to the corresponding MemoryRegionSection in Flatview. Should be + * called from an RCU critical section, to avoid that the last reference + * to the returned memory region disappears after flatview_translate + * returns. + * + * This function is the variant of flatview_translate(), with the difference + * that it accesses the AddressSpace which contains FlatView. + * + * @as: #AddressSpace to be accessed + * @addr: the address to be translated in above address space. + * @xlat: the translated address offset within memory region. + * @len: pointer to length, and it will be changed to valid read/write + * length of the translated address after this function returns. + * @is_write: whether the translation operation is for write. + * @attrs: memory transaction attributes. + */ static inline MemoryRegion *address_space_translate(AddressSpace *as, hwaddr addr, hwaddr *xlat, hwaddr *len, bool is_write, diff --git a/system/physmem.c b/system/physmem.c index 4af29ea2168e..d2106d0ffa87 100644 --- a/system/physmem.c +++ b/system/physmem.c @@ -559,9 +559,9 @@ iotlb_fail: } /* Called from RCU critical section */ -MemoryRegion *flatview_translate(FlatView *fv, hwaddr addr, hwaddr *xlat, - hwaddr *plen, bool is_write, - MemTxAttrs attrs) +MemoryRegionSection *flatview_translate_section(FlatView *fv, hwaddr addr, + hwaddr *xlat, hwaddr *plen, + bool is_write, MemTxAttrs attrs) { MemoryRegion *mr; MemoryRegionSection *section; @@ -577,7 +577,21 @@ MemoryRegion *flatview_translate(FlatView *fv, hwaddr addr, hwaddr *xlat, *plen = MIN(page, *plen); } - return mr; + return section; +} + +/* Called from RCU critical section */ +MemoryRegion *flatview_translate(FlatView *fv, hwaddr addr, hwaddr *xlat, + hwaddr *plen, bool is_write, + MemTxAttrs attrs) +{ + MemoryRegionSection *section; + + /* This can be MMIO, so setup MMIO bit. */ + section = flatview_translate_section(fv, addr, xlat, plen, + is_write, attrs); + + return section->mr; } #ifdef CONFIG_TCG -- 2.34.1
