diff --git a/cpp/include/cudf/io/datasource.hpp b/cpp/include/cudf/io/datasource.hpp index b12fbe39a57..dc14802adc1 100644 --- a/cpp/include/cudf/io/datasource.hpp +++ b/cpp/include/cudf/io/datasource.hpp @@ -86,14 +86,28 @@ class datasource { /** * @brief Creates a source from a file path. * + * @note Parameters `offset`, `max_size_estimate` and `min_size_estimate` are hints to the + * `datasource` implementation about the expected range of the data that will be read. The + * implementation may use these hints to optimize the read operation. These parameters are usually + * based on the byte range option. In this case, `min_size_estimate` should be no greater than the + * byte range to avoid potential issues when reading adjacent ranges. `max_size_estimate` can + * include padding after the byte range, to include additional data that may be needed for + * processing. + * + @throws cudf::logic_error if the minimum size estimate is greater than the maximum size estimate + * * @param[in] filepath Path to the file to use - * @param[in] offset Bytes from the start of the file (the default is zero) - * @param[in] size Bytes from the offset; use zero for entire file (the default is zero) + * @param[in] offset Starting byte offset from which data will be read (the default is zero) + * @param[in] max_size_estimate Upper estimate of the data range that will be read (the default is + * zero, which means the whole file after `offset`) + * @param[in] min_size_estimate Lower estimate of the data range that will be read (the default is + * zero, which means the whole file after `offset`) * @return Constructed datasource object */ static std::unique_ptr create(std::string const& filepath, - size_t offset = 0, - size_t size = 0); + size_t offset = 0, + size_t max_size_estimate = 0, + size_t min_size_estimate = 0); /** * @brief Creates a source from a host memory buffer. diff --git a/cpp/src/io/functions.cpp b/cpp/src/io/functions.cpp index de8eea9e99b..5a060902eb2 100644 --- a/cpp/src/io/functions.cpp +++ b/cpp/src/io/functions.cpp @@ -122,14 +122,16 @@ chunked_parquet_writer_options_builder chunked_parquet_writer_options::builder( namespace { std::vector> make_datasources(source_info const& info, - size_t range_offset = 0, - size_t range_size = 0) + size_t offset = 0, + size_t max_size_estimate = 0, + size_t min_size_estimate = 0) { switch (info.type()) { case io_type::FILEPATH: { auto sources = std::vector>(); for (auto const& filepath : info.filepaths()) { - sources.emplace_back(cudf::io::datasource::create(filepath, range_offset, range_size)); + sources.emplace_back( + cudf::io::datasource::create(filepath, offset, max_size_estimate, min_size_estimate)); } return sources; } @@ -211,7 +213,8 @@ table_with_metadata read_json(json_reader_options options, auto datasources = make_datasources(options.get_source(), options.get_byte_range_offset(), - options.get_byte_range_size_with_padding()); + options.get_byte_range_size_with_padding(), + options.get_byte_range_size()); return json::detail::read_json(datasources, options, stream, mr); } @@ -238,7 +241,8 @@ table_with_metadata read_csv(csv_reader_options options, auto datasources = make_datasources(options.get_source(), options.get_byte_range_offset(), - options.get_byte_range_size_with_padding()); + options.get_byte_range_size_with_padding(), + options.get_byte_range_size()); CUDF_EXPECTS(datasources.size() == 1, "Only a single source is currently supported."); diff --git a/cpp/src/io/utilities/datasource.cpp b/cpp/src/io/utilities/datasource.cpp index e4313eba454..0be976b6144 100644 --- a/cpp/src/io/utilities/datasource.cpp +++ b/cpp/src/io/utilities/datasource.cpp @@ -32,6 +32,7 @@ #include #include +#include namespace cudf { namespace io { @@ -54,6 +55,30 @@ class file_source : public datasource { } } + std::unique_ptr host_read(size_t offset, size_t size) override + { + lseek(_file.desc(), offset, SEEK_SET); + + // Clamp length to available data + ssize_t const read_size = std::min(size, _file.size() - offset); + + std::vector v(read_size); + CUDF_EXPECTS(read(_file.desc(), v.data(), read_size) == read_size, "read failed"); + return buffer::create(std::move(v)); + } + + size_t host_read(size_t offset, size_t size, uint8_t* dst) override + { + lseek(_file.desc(), offset, SEEK_SET); + + // Clamp length to available data + auto const read_size = std::min(size, _file.size() - offset); + + CUDF_EXPECTS(read(_file.desc(), dst, read_size) == static_cast(read_size), + "read failed"); + return read_size; + } + ~file_source() override = default; [[nodiscard]] bool supports_device_read() const override @@ -138,40 +163,63 @@ class file_source : public datasource { */ class memory_mapped_source : public file_source { public: - explicit memory_mapped_source(char const* filepath, size_t offset, size_t size) + explicit memory_mapped_source(char const* filepath, + size_t offset, + size_t max_size_estimate, + size_t min_size_estimate) : file_source(filepath) { if (_file.size() != 0) { - map(_file.desc(), offset, size); - register_mmap_buffer(); + // Memory mapping is not exclusive, so we can include the whole region we expect to read + map(_file.desc(), offset, max_size_estimate); + // Buffer registration is exclusive (can't overlap with other registered buffers) so we + // register the lower estimate; this avoids issues when reading adjacent ranges from the same + // file from multiple threads + register_mmap_buffer(offset, min_size_estimate); } } ~memory_mapped_source() override { if (_map_addr != nullptr) { - munmap(_map_addr, _map_size); + unmap(); unregister_mmap_buffer(); } } std::unique_ptr host_read(size_t offset, size_t size) override { - CUDF_EXPECTS(offset >= _map_offset, "Requested offset is outside mapping"); + // Clamp length to available data + auto const read_size = std::min(size, +_file.size() - offset); + + // If the requested range is outside of the mapped region, read from the file + if (offset < _map_offset or offset + read_size > (_map_offset + _map_size)) { + return file_source::host_read(offset, read_size); + } - // Clamp length to available data in the mapped region - auto const read_size = std::min(size, _map_size - (offset - _map_offset)); + // If the requested range is only partially within the registered region, copy to a new + // host buffer to make the data safe to copy to the device + if (_reg_addr != nullptr and + (offset < _reg_offset or offset + read_size > (_reg_offset + _reg_size))) { + auto const src = static_cast(_map_addr) + (offset - _map_offset); + + return std::make_unique>>( + std::vector(src, src + read_size)); + } return std::make_unique( - static_cast(_map_addr) + (offset - _map_offset), read_size); + static_cast(_map_addr) + offset - _map_offset, read_size); } size_t host_read(size_t offset, size_t size, uint8_t* dst) override { - CUDF_EXPECTS(offset >= _map_offset, "Requested offset is outside mapping"); + // Clamp length to available data + auto const read_size = std::min(size, +_file.size() - offset); - // Clamp length to available data in the mapped region - auto const read_size = std::min(size, _map_size - (offset - _map_offset)); + // If the requested range is outside of the mapped region, read from the file + if (offset < _map_offset or offset + read_size > (_map_offset + _map_size)) { + return file_source::host_read(offset, read_size, dst); + } auto const src = static_cast(_map_addr) + (offset - _map_offset); std::memcpy(dst, src, read_size); @@ -184,16 +232,18 @@ class memory_mapped_source : public file_source { * * Fixes nvbugs/4215160 */ - void register_mmap_buffer() + void register_mmap_buffer(size_t offset, size_t size) { - if (_map_addr == nullptr or _map_size == 0 or not pageableMemoryAccessUsesHostPageTables()) { - return; - } + if (_map_addr == nullptr or not pageableMemoryAccessUsesHostPageTables()) { return; } - auto const result = cudaHostRegister(_map_addr, _map_size, cudaHostRegisterDefault); - if (result == cudaSuccess) { - _is_map_registered = true; - } else { + // Registered region must be within the mapped region + _reg_offset = std::max(offset, _map_offset); + _reg_size = std::min(size != 0 ? size : _map_size, (_map_offset + _map_size) - _reg_offset); + + _reg_addr = static_cast(_map_addr) - _map_offset + _reg_offset; + auto const result = cudaHostRegister(_reg_addr, _reg_size, cudaHostRegisterReadOnly); + if (result != cudaSuccess) { + _reg_addr = nullptr; CUDF_LOG_WARN("cudaHostRegister failed with {} ({})", static_cast(result), cudaGetErrorString(result)); @@ -205,10 +255,12 @@ class memory_mapped_source : public file_source { */ void unregister_mmap_buffer() { - if (not _is_map_registered) { return; } + if (_reg_addr == nullptr) { return; } - auto const result = cudaHostUnregister(_map_addr); - if (result != cudaSuccess) { + auto const result = cudaHostUnregister(_reg_addr); + if (result == cudaSuccess) { + _reg_addr = nullptr; + } else { CUDF_LOG_WARN("cudaHostUnregister failed with {} ({})", static_cast(result), cudaGetErrorString(result)); @@ -226,52 +278,30 @@ class memory_mapped_source : public file_source { // Size for `mmap()` needs to include the page padding _map_size = size + (offset - _map_offset); + if (_map_size == 0) { return; } // Check if accessing a region within already mapped area _map_addr = mmap(nullptr, _map_size, PROT_READ, MAP_PRIVATE, fd, _map_offset); CUDF_EXPECTS(_map_addr != MAP_FAILED, "Cannot create memory mapping"); } - private: - size_t _map_size = 0; - size_t _map_offset = 0; - void* _map_addr = nullptr; - bool _is_map_registered = false; -}; - -/** - * @brief Implementation class for reading from a file using `read` calls - * - * Potentially faster than `memory_mapped_source` when only a small portion of the file is read - * through the host. - */ -class direct_read_source : public file_source { - public: - explicit direct_read_source(char const* filepath) : file_source(filepath) {} - - std::unique_ptr host_read(size_t offset, size_t size) override + void unmap() { - lseek(_file.desc(), offset, SEEK_SET); - - // Clamp length to available data - ssize_t const read_size = std::min(size, _file.size() - offset); - - std::vector v(read_size); - CUDF_EXPECTS(read(_file.desc(), v.data(), read_size) == read_size, "read failed"); - return buffer::create(std::move(v)); + if (_map_addr != nullptr) { + auto const result = munmap(_map_addr, _map_size); + if (result != 0) { CUDF_LOG_WARN("munmap failed with {}", result); } + _map_addr = nullptr; + } } - size_t host_read(size_t offset, size_t size, uint8_t* dst) override - { - lseek(_file.desc(), offset, SEEK_SET); - - // Clamp length to available data - auto const read_size = std::min(size, _file.size() - offset); + private: + size_t _map_offset = 0; + size_t _map_size = 0; + void* _map_addr = nullptr; - CUDF_EXPECTS(read(_file.desc(), dst, read_size) == static_cast(read_size), - "read failed"); - return read_size; - } + size_t _reg_offset = 0; + size_t _reg_size = 0; + void* _reg_addr = nullptr; }; /** @@ -431,16 +461,21 @@ class user_datasource_wrapper : public datasource { std::unique_ptr datasource::create(std::string const& filepath, size_t offset, - size_t size) + size_t max_size_estimate, + size_t min_size_estimate) { + CUDF_EXPECTS(max_size_estimate == 0 or min_size_estimate <= max_size_estimate, + "Invalid min/max size estimates for datasource creation"); + #ifdef CUFILE_FOUND if (cufile_integration::is_always_enabled()) { // avoid mmap as GDS is expected to be used for most reads - return std::make_unique(filepath.c_str()); + return std::make_unique(filepath.c_str()); } #endif // Use our own memory mapping implementation for direct file reads - return std::make_unique(filepath.c_str(), offset, size); + return std::make_unique( + filepath.c_str(), offset, max_size_estimate, min_size_estimate); } std::unique_ptr datasource::create(host_buffer const& buffer) diff --git a/cpp/tests/io/csv_test.cpp b/cpp/tests/io/csv_test.cpp index dc14824d834..0028dd946e3 100644 --- a/cpp/tests/io/csv_test.cpp +++ b/cpp/tests/io/csv_test.cpp @@ -2516,4 +2516,39 @@ TEST_F(CsvReaderTest, UTF8BOM) CUDF_TEST_EXPECT_TABLES_EQUIVALENT(result_view, expected); } +void expect_buffers_equal(cudf::io::datasource::buffer* lhs, cudf::io::datasource::buffer* rhs) +{ + ASSERT_EQ(lhs->size(), rhs->size()); + EXPECT_EQ(0, std::memcmp(lhs->data(), rhs->data(), lhs->size())); +} + +TEST_F(CsvReaderTest, OutOfMapBoundsReads) +{ + // write a lot of data into a file + auto filepath = temp_env->get_temp_dir() + "OutOfMapBoundsReads.csv"; + auto const num_rows = 1 << 20; + auto const row = std::string{"0,1,2,3,4,5,6,7,8,9\n"}; + auto const file_size = num_rows * row.size(); + { + std::ofstream outfile(filepath, std::ofstream::out); + for (size_t i = 0; i < num_rows; ++i) { + outfile << row; + } + } + + // Only memory map the middle of the file + auto source = cudf::io::datasource::create(filepath, file_size / 2, file_size / 4); + auto full_source = cudf::io::datasource::create(filepath); + auto const all_data = source->host_read(0, file_size); + auto ref_data = full_source->host_read(0, file_size); + expect_buffers_equal(ref_data.get(), all_data.get()); + + auto const start_data = source->host_read(file_size / 2, file_size / 2); + expect_buffers_equal(full_source->host_read(file_size / 2, file_size / 2).get(), + start_data.get()); + + auto const end_data = source->host_read(0, file_size / 2 + 512); + expect_buffers_equal(full_source->host_read(0, file_size / 2 + 512).get(), end_data.get()); +} + CUDF_TEST_PROGRAM_MAIN()