ChangeLog: ========= v2 => v3: a) Patch 1 data structure cleanups, header file include cleanups, IDA interface reuse and switching to device_create_with_groups(..) as per feedback from Greg Kroah-Hartman. b) Patch 7 signal documentation, sleep workaround removal and sysfs access API cleanups as per feedback from Michael S. Tsirkin. v1 => v2: @ http://lwn.net/Articles/563131/ a) License wording cleanup, sysfs ABI documentation, patch 1 refactoring into 3 smaller patches and function renames, as per feedback from Greg Kroah-Hartman. b) Use VRINGH infrastructure for accessing virtio rings from the host in patch 5, as per feedback from Michael S. Tsirkin. v1: Initial post @ https://lwn.net/Articles/561314/ Description: ============ An Intel MIC X100 device is a PCIe form factor add-in coprocessor card based on the Intel Many Integrated Core (MIC) architecture that runs a Linux OS. It is a PCIe endpoint in a platform and therefore implements the three required standard address spaces i.e. configuration, memory and I/O. The host OS loads a device driver as is typical for PCIe devices. The card itself runs a bootstrap after reset that transfers control to the card OS downloaded from the host driver. The card OS as shipped by Intel is a Linux kernel with modifications for the X100 devices. Since it is a PCIe card, it does not have the ability to host hardware devices for networking, storage and console. We provide these devices on X100 coprocessors thus enabling a self-bootable equivalent environment for applications. A key benefit of our solution is that it leverages the standard virtio framework for network, disk and console devices, though in our case the virtio framework is used across a PCIe bus. Here is a block diagram of the various components described above. The virtio backends are situated on the host rather than the card given better single threaded performance for the host compared to MIC, the ability of the host to initiate DMA's to/from the card using the MIC DMA engine and the fact that the virtio block storage backend can only be on the host. +----------+ | +----------+ | Card OS | | | Host OS | +----------+ | +----------+ | +-------+ +--------+ +------+ | +---------+ +--------+ +--------+ | Virtio| |Virtio | |Virtio| | |Virtio | |Virtio | |Virtio | | Net | |Console | |Block | | |Net | |Console | |Block | | Driver| |Driver | |Driver| | |backend | |backend | |backend | +-------+ +--------+ +------+ | +---------+ +--------+ +--------+ | | | | | | | | | | |User | | | | | | |------|------------|---------|------- +-------------------+ |Kernel +--------------------------+ | | | Virtio over PCIe IOCTLs | | | +--------------------------+ +--------------+ | | |Intel MIC | | +---------------+ |Card Driver | | |Intel MIC | +--------------+ | |Host Driver | | | +---------------+ | | | +-------------------------------------------------------------+ | | | PCIe Bus | +-------------------------------------------------------------+ The following series of patches are partitioned as follows: Patch 1: This patch introduces the "Intel MIC Host Driver" in the block diagram which does the following: a) Initializes the Intel MIC X100 PCIe devices. b) Provides sysfs entries for family and stepping information. Patch 2: This patch enables the following features in the "Intel MIC Host Driver" in the block diagram: a) MSIx, MSI and legacy interrupt support. b) System Memory Page Table(SMPT) support. SMPT enables system memory access from the card. On X100 devices the host can program 32 SMPT registers each capable of accessing 16GB of system memory address space from X100 devices. The registers can thereby be used to access a cumulative 512GB of system memory address space from X100 devices at any point in time. Patch 3: This patch enables the following features in the "Intel MIC Host Driver" in the block diagram: a) Boots and shuts down the card via sysfs entries. b) Allocates and maps a device page for communication with the card driver and updates the device page address via scratchpad registers. c) Provides sysfs entries for shutdown status, kernel command line, firmware, ramdisk, bootmode and log buffer information. Patch 4: This patch introduces the "Intel MIC Card Driver" in the block diagram which does the following: a) Initializes the Intel MIC X100 platform device and driver. b) Sets up support to handle shutdown requests from the host. c) Maps the device page after obtaining the device page address from the scratchpad registers updated by the host. d) Informs the host upon a card crash by registering a panic notifier. e) Informs the host upon a poweroff/halt event. Patch 5: This patch introduces the host "Virtio over PCIe" interface for Intel MIC. It allows creating user space backends on the host and instantiating virtio devices for them on the Intel MIC card. It uses the existing VRINGH infrastructure in the kernel to access virtio rings from the host. A character device per MIC is exposed with IOCTL, mmap and poll callbacks. This allows the user space backend to: (a) add/remove a virtio device via a device page. (b) map (R/O) virtio rings and device page to user space. (c) poll for availability of data. (d) copy a descriptor or entire descriptor chain to/from the card. (e) modify virtio configuration. (f) handle virtio device reset. The buffers are copied over using CPU copies for this initial patch and host initiated MIC DMA support is planned for future patches. The avail and desc virtio rings are in host memory and the used ring is in card memory to maximize writes across PCIe for performance. Patch 6: This patch introduces the card "Virtio over PCIe" interface for Intel MIC. It allows virtio drivers on the card to communicate with their user space backends on the host via a device page. Ring 3 apps on the host can add, remove and configure virtio devices. A thin MIC specific virtio_config_ops is implemented which is borrowed heavily from previous similar implementations in lguest and s390 @ drivers/lguest/lguest_device.c drivers/s390/kvm/kvm_virtio.c Patch 7: This patch introduces a sample user space daemon which implements the virtio device backends on the host. The daemon creates/removes/configures virtio device backends by communicating with the Intel MIC Host Driver. The virtio devices currently supported are virtio net, virtio console and virtio block. Virtio net supports TSO/GSO. The daemon also monitors card shutdown status and takes appropriate actions like killing the virtio backends and resetting the card upon card shutdown and crashes. The patches have been compiled/validated against v3.11-rc5. Ashutosh Dixit (2): Intel MIC Host Driver Changes for Virtio Devices. Intel MIC Card Driver Changes for Virtio Devices. Caz Yokoyama (1): Sample Implementation of Intel MIC User Space Daemon. Dasaratharaman Chandramouli (1): Intel MIC Host Driver Interrupt/SMPT support. Sudeep Dutt (3): Intel MIC Host Driver for X100 family. Intel MIC Host Driver, card OS state management. Intel MIC Card Driver for X100 family. Documentation/ABI/testing/sysfs-class-mic.txt | 147 +++ Documentation/mic/mic_overview.txt | 49 + Documentation/mic/mpssd/.gitignore | 1 + Documentation/mic/mpssd/Makefile | 19 + Documentation/mic/mpssd/micctrl | 173 +++ Documentation/mic/mpssd/mpss | 202 +++ Documentation/mic/mpssd/mpssd.c | 1701 +++++++++++++++++++++++++ Documentation/mic/mpssd/mpssd.h | 100 ++ Documentation/mic/mpssd/sysfs.c | 102 ++ drivers/misc/Kconfig | 1 + drivers/misc/Makefile | 1 + drivers/misc/mic/Kconfig | 39 + drivers/misc/mic/Makefile | 6 + drivers/misc/mic/card/Makefile | 11 + drivers/misc/mic/card/mic_debugfs.c | 130 ++ drivers/misc/mic/card/mic_device.c | 306 +++++ drivers/misc/mic/card/mic_device.h | 133 ++ drivers/misc/mic/card/mic_virtio.c | 631 +++++++++ drivers/misc/mic/card/mic_virtio.h | 77 ++ drivers/misc/mic/card/mic_x100.c | 256 ++++ drivers/misc/mic/card/mic_x100.h | 48 + drivers/misc/mic/common/mic_device.h | 51 + drivers/misc/mic/host/Makefile | 13 + drivers/misc/mic/host/mic_boot.c | 185 +++ drivers/misc/mic/host/mic_debugfs.c | 496 +++++++ drivers/misc/mic/host/mic_device.h | 300 +++++ drivers/misc/mic/host/mic_fops.c | 221 ++++ drivers/misc/mic/host/mic_fops.h | 32 + drivers/misc/mic/host/mic_main.c | 1098 ++++++++++++++++ drivers/misc/mic/host/mic_smpt.c | 440 +++++++ drivers/misc/mic/host/mic_smpt.h | 98 ++ drivers/misc/mic/host/mic_sysfs.c | 468 +++++++ drivers/misc/mic/host/mic_virtio.c | 704 ++++++++++ drivers/misc/mic/host/mic_virtio.h | 138 ++ drivers/misc/mic/host/mic_x100.c | 573 +++++++++ drivers/misc/mic/host/mic_x100.h | 99 ++ include/uapi/linux/Kbuild | 2 + include/uapi/linux/mic_common.h | 238 ++++ include/uapi/linux/mic_ioctl.h | 74 ++ 39 files changed, 9363 insertions(+) create mode 100644 Documentation/ABI/testing/sysfs-class-mic.txt create mode 100644 Documentation/mic/mic_overview.txt create mode 100644 Documentation/mic/mpssd/.gitignore create mode 100644 Documentation/mic/mpssd/Makefile create mode 100755 Documentation/mic/mpssd/micctrl create mode 100755 Documentation/mic/mpssd/mpss create mode 100644 Documentation/mic/mpssd/mpssd.c create mode 100644 Documentation/mic/mpssd/mpssd.h create mode 100644 Documentation/mic/mpssd/sysfs.c create mode 100644 drivers/misc/mic/Kconfig create mode 100644 drivers/misc/mic/Makefile create mode 100644 drivers/misc/mic/card/Makefile create mode 100644 drivers/misc/mic/card/mic_debugfs.c create mode 100644 drivers/misc/mic/card/mic_device.c create mode 100644 drivers/misc/mic/card/mic_device.h create mode 100644 drivers/misc/mic/card/mic_virtio.c create mode 100644 drivers/misc/mic/card/mic_virtio.h create mode 100644 drivers/misc/mic/card/mic_x100.c create mode 100644 drivers/misc/mic/card/mic_x100.h create mode 100644 drivers/misc/mic/common/mic_device.h create mode 100644 drivers/misc/mic/host/Makefile create mode 100644 drivers/misc/mic/host/mic_boot.c create mode 100644 drivers/misc/mic/host/mic_debugfs.c create mode 100644 drivers/misc/mic/host/mic_device.h create mode 100644 drivers/misc/mic/host/mic_fops.c create mode 100644 drivers/misc/mic/host/mic_fops.h create mode 100644 drivers/misc/mic/host/mic_main.c create mode 100644 drivers/misc/mic/host/mic_smpt.c create mode 100644 drivers/misc/mic/host/mic_smpt.h create mode 100644 drivers/misc/mic/host/mic_sysfs.c create mode 100644 drivers/misc/mic/host/mic_virtio.c create mode 100644 drivers/misc/mic/host/mic_virtio.h create mode 100644 drivers/misc/mic/host/mic_x100.c create mode 100644 drivers/misc/mic/host/mic_x100.h create mode 100644 include/uapi/linux/mic_common.h create mode 100644 include/uapi/linux/mic_ioctl.h -- 1.8.2.1 -- To unsubscribe from this list: send the line "unsubscribe linux-doc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
