mmap

About: mmap is a research topic. Over the lifetime, 137 publications have been published within this topic receiving 2481 citations.

Linux Device Drivers

Abstract: Preface. Chapter 1. An Introduction to Device Drivers The Role of the Device Driver Splitting the Kernel Classes of Devices and Modules Security Issues Version Numbering License Terms Joining the Kernel Development Community Overview of the Book. Chapter 2. Building and Running Modules Kernel Modules Versus Applications Compiling and Loading The Kernel Symbol Table Initialization and Shutdown Using Resources Automatic and Manual Configuration Doing It in User Space Backward Compatibility Quick Reference. Chapter 3. Char Drivers The Design of scull Major and Minor Numbers File Operations The file Structure open and release scull's Memory Usage A Brief Introduction to Race Conditions read and write Playing with the New Devices The Device Filesystem Backward Compatibility Quick Reference. Chapter 4. Debugging Techniques Debugging by Printing Debugging by Querying Debugging by Watching Debugging System Faults Debuggers and Related Tools. Chapter 5. Enhanced Char Driver Operations ioctl Blocking I/O poll and select Asynchronous Notification Seeking a Device Access Control on a Device File Backward Compatibility Quick Reference. Chapter 6. Flow of Time Time Intervals in the Kernel Knowing the Current Time Delaying Execution Task Queues Kernel Timers Backward Compatibility Quick Reference. Chapter 7. Getting Hold of Memory The Real Story of kmalloc Lookaside Caches get_free_page and Friends vmalloc and Friends Boot-Time Allocation Backward Compatibility Quick Reference Chapter 8. Hardware Management I/O Ports and I/O Memory Using I/O Ports Using Digital I/O Ports Using I/O Memory Backward Compatibility Quick Reference. Chapter 9. Interrupt Handling Overall Control of Interrupts Preparing the Parallel Port Installing an Interrupt Handler Implementing a Handler Tasklets and Bottom-Half Processing Interrupt Sharing Interrupt-Driven I/O Race Conditions Backward Compatibility Quick Reference. Chapter 10. Judicious Use of Data Types Use of Standard C Types Assigning an Explicit Size to Data Items Interface-Specific Types Other Portability Issues Linked Lists Quick Reference. Chapter 11. kmod and Advanced Modularization Loading Modules on Demand Intermodule Communication Version Control in Modules Backward Compatibility Quick Reference. Chapter 12. Loading Block Drivers Registering the Driver The Header File blk.h Handling Requests: A Simple Introduction Handling Requests: The Detailed View How Mounting and Unmounting Works The ioctl Method Removable Devices Partitionable Devices Interrupt-Driven Block Drivers Backward Compatibility Quick Reference. Chapter 13. mmap and DMA Memory Management in Linux The mmap Device Operation The kiobuf Interface Direct Memory Access and Bus Mastering Backward Compatibility Quick Reference. Chapter 14. Network Drivers How snull Is Designed Connecting to the Kernel The net_device Structure in Detail Opening and Closing Packet Transmission Packet Reception The Interrupt Handler Changes in Link State The Socket Buffers MAC Address Resolution Custom ioctl Commands Statistical Information Multicasting Backward Compatibility Quick Reference. Chapter 15. Overview of Peripheral Buses The PCI Interface A Look Back: ISA PC/104 and PC/104+ Other PC Buses SBus NuBus External Buses Backward Compatibility Quick Reference. Chapter 16. Physical Layout of the Kernel Source Booting the Kernel Before Booting The init Process The kernel Directory The fs Directory The mm Directory The net directory ipc and lib include and arch Drivers. Glossary. Index

NOVA: a log-structured file system for hybrid volatile/non-volatile main memories

Abstract: Fast non-volatile memories (NVMs) will soon appear on the processor memory bus alongside DRAM. The resulting hybrid memory systems will provide software with sub-microsecond, high-bandwidth access to persistent data, but managing, accessing, and maintaining consistency for data stored in NVM raises a host of challenges. Existing file systems built for spinning or solid-state disks introduce software overheads that would obscure the performance that NVMs should provide, but proposed file systems for NVMs either incur similar overheads or fail to provide the strong consistency guarantees that applications require. We present NOVA, a file system designed to maximize performance on hybrid memory systems while providing strong consistency guarantees. NOVA adapts conventional log-structured file system techniques to exploit the fast random access that NVMs provide. In particular, it maintains separate logs for each inode to improve concurrency, and stores file data outside the log to minimize log size and reduce garbage collection costs. NOVA's logs provide metadata, data, and mmap atomicity and focus on simplicity and reliability, keeping complex metadata structures in DRAM to accelerate lookup operations. Experimental results show that in write-intensive workloads, NOVA provides 22% to 216× throughput improvement compared to state-of-the-art file systems, and 3.1× to 13.5× improvement compared to file systems that provide equally strong data consistency guarantees.

DMTCP: Transparent checkpointing for cluster computations and the desktop

Abstract: DMTCP (Distributed MultiThreaded CheckPointing) is a transparent user-level checkpointing package for distributed applications. Checkpointing and restart is demonstrated for a wide range of over 20 well known applications, including MATLAB, Python, TightVNC, MPICH2, OpenMPI, and runCMS. RunCMS runs as a 680 MB image in memory that includes 540 dynamic libraries, and is used for the CMS experiment of the Large Hadron Collider at CERN. DMTCP transparently checkpoints general cluster computations consisting of many nodes, processes, and threads; as well as typical desktop applications. On 128 distributed cores (32 nodes), checkpoint and restart times are typically 2 seconds, with negligible run-time overhead. Typical checkpoint times are reduced to 0.2 seconds when using forked checkpointing. Experimental results show that checkpoint time remains nearly constant as the number of nodes increases on a medium-size cluster. DMTCP automatically accounts for fork, exec, ssh, mutexes/ semaphores, TCP/IP sockets, UNIX domain sockets, pipes, ptys (pseudo-terminals), terminal modes, ownership of controlling terminals, signal handlers, open file descriptors, shared open file descriptors, I/O (including the readline library), shared memory (via mmap), parent-child process relationships, pid virtualization, and other operating system artifacts. By emphasizing an unprivileged, user-space approach, compatibility is maintained across Linux kernels from 2.6.9 through the current 2.6.28. Since DMTCP is unprivileged and does not require special kernel modules or kernel patches, DMTCP can be incorporated and distributed as a checkpoint-restart module within some larger package.

Zeroizing Without Low-Level Zeroes: New MMAP Attacks and their Limitations

Abstract: We extend the recent zeroizing attacks of Cheon, Han, Lee, Ryu and Stehle (Eurocrypt’15) on multilinear maps to settings where no encodings of zero below the maximal level are available. Some of the new attacks apply to the CLT13 scheme (resulting in a total break) while others apply to (a variant of) the GGH13 scheme (resulting in a weak-DL attack). We also note the limits of these zeroizing attacks.

RadixVM: scalable address spaces for multithreaded applications

Abstract: RadixVM is a new virtual memory system design that enables fully concurrent operations on shared address spaces for multithreaded processes on cache-coherent multicore computers. Today, most operating systems serialize operations such as mmap and munmap, which forces application developers to split their multithreaded applications into multiprocess applications, hoard memory to avoid the overhead of returning it, and so on. RadixVM removes this burden from application developers by ensuring that address space operations on non-overlapping memory regions scale perfectly. It does so by combining three techniques: 1) it organizes metadata in a radix tree instead of a balanced tree to avoid unnecessary cache line movement; 2) it uses a novel memory-efficient distributed reference counting scheme; and 3) it uses a new scheme to target remote TLB shootdowns and to often avoid them altogether. Experiments on an 80 core machine show that RadixVM achieves perfect scalability for non-overlapping regions: if several threads mmap or munmap pages in parallel, they can run completely independently and induce no cache coherence traffic.