diff options
Diffstat (limited to 'include/boost/afio/v2.0/detail/impl/posix/map_handle.ipp')
| -rw-r--r-- | include/boost/afio/v2.0/detail/impl/posix/map_handle.ipp | 155 |
1 files changed, 75 insertions, 80 deletions
diff --git a/include/boost/afio/v2.0/detail/impl/posix/map_handle.ipp b/include/boost/afio/v2.0/detail/impl/posix/map_handle.ipp index 852a428a..78fa9370 100644 --- a/include/boost/afio/v2.0/detail/impl/posix/map_handle.ipp +++ b/include/boost/afio/v2.0/detail/impl/posix/map_handle.ipp @@ -52,7 +52,7 @@ result<section_handle> section_handle::section(file_handle &backing, extent_type maximum_size = utils::round_up_to_page_size(maximum_size); result<section_handle> ret(section_handle(native_handle_type(), backing.is_valid() ? &backing : nullptr, maximum_size, _flag)); // There are no section handles on POSIX, so do nothing - BOOST_AFIO_LOG_FUNCTION_CALL(nativeh.h); + BOOST_AFIO_LOG_FUNCTION_CALL(ret.value()._v.fd); return ret; } @@ -104,17 +104,10 @@ native_handle_type map_handle::release() noexcept return native_handle_type(); } - -result<map_handle> map_handle::map(section_handle §ion, size_type bytes, extent_type offset, section_handle::flag _flag) noexcept +inline result<void *> do_mmap(native_handle_type &nativeh, void *ataddr, section_handle §ion, map_handle::size_type bytes, map_handle::extent_type offset, section_handle::flag _flag) noexcept { - if(!section.backing) - { - // Do NOT round up bytes to the nearest page size, it causes an attempt to extend the file - bytes = utils::round_up_to_page_size(bytes); - } - result<map_handle> ret(map_handle(io_handle(), §ion)); - native_handle_type &nativeh = ret.get()._v; - int prot = 0, int flags = backing ? MAP_SHARED : MAP_ANONYMOUS; + bool have_backing = section.backing(); + int prot = 0, flags = have_backing ? MAP_SHARED : MAP_ANONYMOUS; void *addr = nullptr; if(_flag == section_handle::flag::none) { @@ -152,116 +145,118 @@ result<map_handle> map_handle::map(section_handle §ion, size_type bytes, ext flags |= MAP_PREFAULT_READ; #endif #ifdef MAP_NOSYNC - if(section.backing && (section.backing->kernel_caching() == handle::caching::temporary)) + if(have_backing && (section.backing()->kernel_caching() == handle::caching::temporary)) flags |= MAP_NOSYNC; #endif - addr = ::mmap(nullptr, bytes, prot, flags, section.native_handle().fd, offset); + addr = ::mmap(ataddr, bytes, prot, flags, have_backing ? section.backing_native_handle().fd : -1, offset); if(!addr) - return make_errored_result<map_handle>(errno); + return make_errored_result<void *>(errno); + return addr; +} + +result<map_handle> map_handle::map(section_handle §ion, size_type bytes, extent_type offset, section_handle::flag _flag) noexcept +{ + if(!section.backing()) + { + // Do NOT round up bytes to the nearest page size for backed maps, it causes an attempt to extend the file + bytes = utils::round_up_to_page_size(bytes); + } + result<map_handle> ret(map_handle(io_handle(), §ion)); + native_handle_type &nativeh = ret.get()._v; + BOOST_OUTCOME_TRY(addr, do_mmap(nativeh, nullptr, section, bytes, offset, _flag)); ret.get()._addr = (char *) addr; - ret.get()._length = _bytes; + ret.get()._offset = offset; + ret.get()._length = bytes; // Make my handle borrow the native handle of my backing storage - ret.get()._v.h = section.backing_native_handle().h; - BOOST_AFIO_LOG_FUNCTION_CALL(ret.get()._v.h); + ret.get()._v.fd = section.backing_native_handle().fd; + BOOST_AFIO_LOG_FUNCTION_CALL(ret.get()._v.fd); return ret; } - - - - - - - - - - - - - - - - - - - - - - result<map_handle::buffer_type> map_handle::commit(buffer_type region, section_handle::flag _flag) noexcept { + BOOST_AFIO_LOG_FUNCTION_CALL(_v.fd); + if(!region.first) + return make_errored_result<map_handle::buffer_type>(stl11::errc::invalid_argument); + // Set permissions on the pages + region = utils::round_to_page_size(region); + extent_type offset = _offset + (region.first - _addr); + size_type bytes = region.second; + BOOST_OUTCOME_TRYV(do_mmap(_v, region.first, section, bytes, offset, _flag)); + // Tell the kernel we will be using these pages soon + if(-1 == ::madvise(region.first, region.second, MADV_WILLNEED)) + return make_errored_result<map_handle::buffer_type>(errno); + return region; +} + +result<map_handle::buffer_type> map_handle::decommit(buffer_type region) noexcept +{ BOOST_AFIO_LOG_FUNCTION_CALL(_v.h); if(!region.first) return make_errored_result<map_handle::buffer_type>(stl11::errc::invalid_argument); - DWORD prot = 0; - if(_flag == section_handle::flag::none) - { - BOOST_OUTCOME_TRY(_region, do_not_store(region)); - DWORD _ = 0; - if(!VirtualProtect(_region.first, _region.second, PAGE_NOACCESS, &_)) - return make_errored_result<buffer_type>(GetLastError()); - return _region; - } - if(_flag & section_handle::flag::cow) - { - prot = PAGE_WRITECOPY; - _v.behaviour |= native_handle_type::disposition::seekable | native_handle_type::disposition::readable | native_handle_type::disposition::writable; - } - else if(_flag & section_handle::flag::write) - { - prot = PAGE_READWRITE; - _v.behaviour |= native_handle_type::disposition::seekable | native_handle_type::disposition::readable | native_handle_type::disposition::writable; - } - else if(_flag & section_handle::flag::read) - { - prot = PAGE_READONLY; - _v.behaviour |= native_handle_type::disposition::seekable | native_handle_type::disposition::readable; - } - if(_flag & section_handle::flag::execute) - prot = PAGE_EXECUTE; region = utils::round_to_page_size(region); - if(!VirtualAlloc(region.first, region.second, MEM_COMMIT, prot)) - return make_errored_result<buffer_type>(GetLastError()); + // Tell the kernel to kick these pages into storage + if(-1 == ::madvise(region.first, region.second, MADV_DONTNEED)) + return make_errored_result<map_handle::buffer_type>(errno); + // Set permissions on the pages to no access + extent_type offset = _offset + (region.first - _addr); + size_type bytes = region.second; + BOOST_OUTCOME_TRYV(do_mmap(_v, region.first, section, bytes, offset, section_handle::flag::none)); return region; } result<void> map_handle::zero(buffer_type region) noexcept { - BOOST_AFIO_LOG_FUNCTION_CALL(_v.h); + BOOST_AFIO_LOG_FUNCTION_CALL(_v.fd); if(!region.first) return make_errored_result<void>(stl11::errc::invalid_argument); +#ifdef MADV_REMOVE + buffer_type page_region { (char *) utils::round_up_to_page_size((uintptr_t) region.first), utils::round_down_to_page_size(region.second) }; + // Zero contents and punch a hole in any backing storage + if(page_region.second && -1 != ::madvise(page_region.first, page_region.second, MADV_REMOVE)) + { + memset(region.first, 0, page_region.first - region.first); + memset(page_region.first + page_region.second, 0, (region.first + region.second) - (page_region.first + page_region.second)); + return make_valued_result<void>(); + } +#endif //! \todo Once you implement file_handle::zero(), please implement map_handle::zero() - // buffer_type page_region { (char *) utils::round_up_to_page_size((uintptr_t) region.first), utils::round_down_to_page_size(region.second); }; memset(region.first, 0, region.second); return make_valued_result<void>(); } result<span<map_handle::buffer_type>> map_handle::prefetch(span<buffer_type> regions) noexcept { - windows_nt_kernel::init(); - using namespace windows_nt_kernel; BOOST_AFIO_LOG_FUNCTION_CALL(0); - if(!PrefetchVirtualMemory_) - return span<map_handle::buffer_type>(); - PWIN32_MEMORY_RANGE_ENTRY wmre = (PWIN32_MEMORY_RANGE_ENTRY) regions.data(); - if(!PrefetchVirtualMemory_(GetCurrentProcess(), regions.size(), wmre, 0)) - return make_errored_result<span<map_handle::buffer_type>>(GetLastError()); + for(const auto ®ion : regions) + { + if(-1 == ::madvise(region.first, region.second, MADV_WILLNEED)) + return make_errored_result<span<map_handle::buffer_type>>(errno); + } return regions; } result<map_handle::buffer_type> map_handle::do_not_store(buffer_type region) noexcept { + BOOST_AFIO_LOG_FUNCTION_CALL(0); region = utils::round_to_page_size(region); if(!region.first) return make_errored_result<map_handle::buffer_type>(stl11::errc::invalid_argument); - if(!VirtualAlloc(region.first, region.second, MEM_RESET, 0)) - return make_errored_result<buffer_type>(GetLastError()); +#ifdef MADV_FREE + // Tell the kernel to throw away the contents of these pages + if(-1 == ::madvise(_region.first, _region.second, MADV_FREE)) + return make_errored_result<map_handle::buffer_type>(errno); + else + return region; +#endif + // No support on this platform + region.second = 0; return region; } map_handle::io_result<map_handle::buffers_type> map_handle::read(io_request<buffers_type> reqs, deadline) noexcept { - BOOST_AFIO_LOG_FUNCTION_CALL(_v.h); + BOOST_AFIO_LOG_FUNCTION_CALL(_v.fd); char *addr = _addr + reqs.offset; size_type togo = (size_type)(_length - reqs.offset); for(buffer_type &req : reqs.buffers) @@ -282,7 +277,7 @@ map_handle::io_result<map_handle::buffers_type> map_handle::read(io_request<buff map_handle::io_result<map_handle::const_buffers_type> map_handle::write(io_request<const_buffers_type> reqs, deadline) noexcept { - BOOST_AFIO_LOG_FUNCTION_CALL(_v.h); + BOOST_AFIO_LOG_FUNCTION_CALL(_v.fd); char *addr = _addr + reqs.offset; size_type togo = (size_type)(_length - reqs.offset); for(const_buffer_type &req : reqs.buffers) |