From 0eca353e7ae75a56d5a10cd1c0ff1f06d89e60e3 Mon Sep 17 00:00:00 2001 From: "Bryant G. Ly" Date: Wed, 25 Apr 2018 16:32:57 -0500 Subject: [PATCH] misc: IBM Virtual Management Channel Driver (VMC) This driver is a logical device which provides an interface between the hypervisor and a management partition. This interface is like a message passing interface. This management partition is intended to provide an alternative to HMC-based system management. VMC enables the Management LPAR to provide basic logical partition functions: - Logical Partition Configuration - Boot, start, and stop actions for individual partitions - Display of partition status - Management of virtual Ethernet - Management of virtual Storage - Basic system management This driver is to be used for the POWER Virtual Management Channel Virtual Adapter on the PowerPC platform. It provides a character device which allows for both request/response and async message support through the /dev/ibmvmc node. Signed-off-by: Bryant G. Ly Reviewed-by: Steven Royer Reviewed-by: Adam Reznechek Reviewed-by: Randy Dunlap Tested-by: Taylor Jakobson Tested-by: Brad Warrum Cc: Greg Kroah-Hartman Cc: Arnd Bergmann Cc: Benjamin Herrenschmidt Cc: Michael Ellerman Signed-off-by: Greg Kroah-Hartman --- Documentation/ioctl/ioctl-number.txt | 1 + Documentation/misc-devices/ibmvmc.rst | 226 +++ MAINTAINERS | 6 + arch/powerpc/include/asm/hvcall.h | 1 + drivers/misc/Kconfig | 14 + drivers/misc/Makefile | 1 + drivers/misc/ibmvmc.c | 2418 +++++++++++++++++++++++++ drivers/misc/ibmvmc.h | 209 +++ 8 files changed, 2876 insertions(+) create mode 100644 Documentation/misc-devices/ibmvmc.rst create mode 100644 drivers/misc/ibmvmc.c create mode 100644 drivers/misc/ibmvmc.h diff --git a/Documentation/ioctl/ioctl-number.txt b/Documentation/ioctl/ioctl-number.txt index 7f7413e597f3..be8a98b9e6c4 100644 --- a/Documentation/ioctl/ioctl-number.txt +++ b/Documentation/ioctl/ioctl-number.txt @@ -327,6 +327,7 @@ Code Seq#(hex) Include File Comments 0xCA 80-BF uapi/scsi/cxlflash_ioctl.h 0xCB 00-1F CBM serial IEC bus in development: +0xCC 00-0F drivers/misc/ibmvmc.h pseries VMC driver 0xCD 01 linux/reiserfs_fs.h 0xCF 02 fs/cifs/ioctl.c 0xDB 00-0F drivers/char/mwave/mwavepub.h diff --git a/Documentation/misc-devices/ibmvmc.rst b/Documentation/misc-devices/ibmvmc.rst new file mode 100644 index 000000000000..46ded79554d4 --- /dev/null +++ b/Documentation/misc-devices/ibmvmc.rst @@ -0,0 +1,226 @@ +.. SPDX-License-Identifier: GPL-2.0+ +====================================================== +IBM Virtual Management Channel Kernel Driver (IBMVMC) +====================================================== + +:Authors: + Dave Engebretsen , + Adam Reznechek , + Steven Royer , + Bryant G. Ly , + +Introduction +============ + +Note: Knowledge of virtualization technology is required to understand +this document. + +A good reference document would be: + +https://openpowerfoundation.org/wp-content/uploads/2016/05/LoPAPR_DRAFT_v11_24March2016_cmt1.pdf + +The Virtual Management Channel (VMC) is a logical device which provides an +interface between the hypervisor and a management partition. This interface +is like a message passing interface. This management partition is intended +to provide an alternative to systems that use a Hardware Management +Console (HMC) - based system management. + +The primary hardware management solution that is developed by IBM relies +on an appliance server named the Hardware Management Console (HMC), +packaged as an external tower or rack-mounted personal computer. In a +Power Systems environment, a single HMC can manage multiple POWER +processor-based systems. + +Management Application +---------------------- + +In the management partition, a management application exists which enables +a system administrator to configure the system’s partitioning +characteristics via a command line interface (CLI) or Representational +State Transfer Application (REST API's). + +The management application runs on a Linux logical partition on a +POWER8 or newer processor-based server that is virtualized by PowerVM. +System configuration, maintenance, and control functions which +traditionally require an HMC can be implemented in the management +application using a combination of HMC to hypervisor interfaces and +existing operating system methods. This tool provides a subset of the +functions implemented by the HMC and enables basic partition configuration. +The set of HMC to hypervisor messages supported by the management +application component are passed to the hypervisor over a VMC interface, +which is defined below. + +The VMC enables the management partition to provide basic partitioning +functions: + +- Logical Partitioning Configuration +- Start, and stop actions for individual partitions +- Display of partition status +- Management of virtual Ethernet +- Management of virtual Storage +- Basic system management + +Virtual Management Channel (VMC) +-------------------------------- + +A logical device, called the Virtual Management Channel (VMC), is defined +for communicating between the management application and the hypervisor. It +basically creates the pipes that enable virtualization management +software. This device is presented to a designated management partition as +a virtual device. + +This communication device uses Command/Response Queue (CRQ) and the +Remote Direct Memory Access (RDMA) interfaces. A three-way handshake is +defined that must take place to establish that both the hypervisor and +management partition sides of the channel are running prior to +sending/receiving any of the protocol messages. + +This driver also utilizes Transport Event CRQs. CRQ messages are sent +when the hypervisor detects one of the peer partitions has abnormally +terminated, or one side has called H_FREE_CRQ to close their CRQ. +Two new classes of CRQ messages are introduced for the VMC device. VMC +Administrative messages are used for each partition using the VMC to +communicate capabilities to their partner. HMC Interface messages are used +for the actual flow of HMC messages between the management partition and +the hypervisor. As most HMC messages far exceed the size of a CRQ buffer, +a virtual DMA (RMDA) of the HMC message data is done prior to each HMC +Interface CRQ message. Only the management partition drives RDMA +operations; hypervisors never directly cause the movement of message data. + + +Terminology +----------- +RDMA + Remote Direct Memory Access is DMA transfer from the server to its + client or from the server to its partner partition. DMA refers + to both physical I/O to and from memory operations and to memory + to memory move operations. +CRQ + Command/Response Queue a facility which is used to communicate + between partner partitions. Transport events which are signaled + from the hypervisor to partition are also reported in this queue. + +Example Management Partition VMC Driver Interface +================================================= + +This section provides an example for the management application +implementation where a device driver is used to interface to the VMC +device. This driver consists of a new device, for example /dev/ibmvmc, +which provides interfaces to open, close, read, write, and perform +ioctl’s against the VMC device. + +VMC Interface Initialization +---------------------------- + +The device driver is responsible for initializing the VMC when the driver +is loaded. It first creates and initializes the CRQ. Next, an exchange of +VMC capabilities is performed to indicate the code version and number of +resources available in both the management partition and the hypervisor. +Finally, the hypervisor requests that the management partition create an +initial pool of VMC buffers, one buffer for each possible HMC connection, +which will be used for management application session initialization. +Prior to completion of this initialization sequence, the device returns +EBUSY to open() calls. EIO is returned for all open() failures. + +:: + + Management Partition Hypervisor + CRQ INIT + ----------------------------------------> + CRQ INIT COMPLETE + <---------------------------------------- + CAPABILITIES + ----------------------------------------> + CAPABILITIES RESPONSE + <---------------------------------------- + ADD BUFFER (HMC IDX=0,1,..) _ + <---------------------------------------- | + ADD BUFFER RESPONSE | - Perform # HMCs Iterations + ----------------------------------------> - + +VMC Interface Open +------------------ + +After the basic VMC channel has been initialized, an HMC session level +connection can be established. The application layer performs an open() to +the VMC device and executes an ioctl() against it, indicating the HMC ID +(32 bytes of data) for this session. If the VMC device is in an invalid +state, EIO will be returned for the ioctl(). The device driver creates a +new HMC session value (ranging from 1 to 255) and HMC index value (starting +at index 0 and ranging to 254) for this HMC ID. The driver then does an +RDMA of the HMC ID to the hypervisor, and then sends an Interface Open +message to the hypervisor to establish the session over the VMC. After the +hypervisor receives this information, it sends Add Buffer messages to the +management partition to seed an initial pool of buffers for the new HMC +connection. Finally, the hypervisor sends an Interface Open Response +message, to indicate that it is ready for normal runtime messaging. The +following illustrates this VMC flow: + +:: + + Management Partition Hypervisor + RDMA HMC ID + ----------------------------------------> + Interface Open + ----------------------------------------> + Add Buffer _ + <---------------------------------------- | + Add Buffer Response | - Perform N Iterations + ----------------------------------------> - + Interface Open Response + <---------------------------------------- + +VMC Interface Runtime +--------------------- + +During normal runtime, the management application and the hypervisor +exchange HMC messages via the Signal VMC message and RDMA operations. When +sending data to the hypervisor, the management application performs a +write() to the VMC device, and the driver RDMA’s the data to the hypervisor +and then sends a Signal Message. If a write() is attempted before VMC +device buffers have been made available by the hypervisor, or no buffers +are currently available, EBUSY is returned in response to the write(). A +write() will return EIO for all other errors, such as an invalid device +state. When the hypervisor sends a message to the management, the data is +put into a VMC buffer and an Signal Message is sent to the VMC driver in +the management partition. The driver RDMA’s the buffer into the partition +and passes the data up to the appropriate management application via a +read() to the VMC device. The read() request blocks if there is no buffer +available to read. The management application may use select() to wait for +the VMC device to become ready with data to read. + +:: + + Management Partition Hypervisor + MSG RDMA + ----------------------------------------> + SIGNAL MSG + ----------------------------------------> + SIGNAL MSG + <---------------------------------------- + MSG RDMA + <---------------------------------------- + +VMC Interface Close +------------------- + +HMC session level connections are closed by the management partition when +the application layer performs a close() against the device. This action +results in an Interface Close message flowing to the hypervisor, which +causes the session to be terminated. The device driver must free any +storage allocated for buffers for this HMC connection. + +:: + + Management Partition Hypervisor + INTERFACE CLOSE + ----------------------------------------> + INTERFACE CLOSE RESPONSE + <---------------------------------------- + +Additional Information +====================== + +For more information on the documentation for CRQ Messages, VMC Messages, +HMC interface Buffers, and signal messages please refer to the Linux on +Power Architecture Platform Reference. Section F. diff --git a/MAINTAINERS b/MAINTAINERS index 20032feaa9e7..4f5d8932a6c8 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -6757,6 +6757,12 @@ L: linux-scsi@vger.kernel.org S: Supported F: drivers/scsi/ibmvscsi/ibmvfc* +IBM Power Virtual Management Channel Driver +M: Bryant G. Ly +M: Steven Royer +S: Supported +F: drivers/misc/ibmvmc.* + IBM Power Virtual SCSI Device Drivers M: Tyrel Datwyler L: linux-scsi@vger.kernel.org diff --git a/arch/powerpc/include/asm/hvcall.h b/arch/powerpc/include/asm/hvcall.h index 2e2dddab5d65..662c8347d699 100644 --- a/arch/powerpc/include/asm/hvcall.h +++ b/arch/powerpc/include/asm/hvcall.h @@ -279,6 +279,7 @@ #define H_GET_MPP_X 0x314 #define H_SET_MODE 0x31C #define H_CLEAR_HPT 0x358 +#define H_REQUEST_VMC 0x360 #define H_RESIZE_HPT_PREPARE 0x36C #define H_RESIZE_HPT_COMMIT 0x370 #define H_REGISTER_PROC_TBL 0x37C diff --git a/drivers/misc/Kconfig b/drivers/misc/Kconfig index 5d713008749b..3726eacdf65d 100644 --- a/drivers/misc/Kconfig +++ b/drivers/misc/Kconfig @@ -113,6 +113,20 @@ config IBM_ASM for information on the specific driver level and support statement for your IBM server. +config IBMVMC + tristate "IBM Virtual Management Channel support" + depends on PPC_PSERIES + help + This is the IBM POWER Virtual Management Channel + + This driver is to be used for the POWER Virtual + Management Channel virtual adapter on the PowerVM + platform. It provides both request/response and + async message support through the /dev/ibmvmc node. + + To compile this driver as a module, choose M here: the + module will be called ibmvmc. + config PHANTOM tristate "Sensable PHANToM (PCI)" depends on PCI diff --git a/drivers/misc/Makefile b/drivers/misc/Makefile index 20be70c3f118..af22bbc3d00c 100644 --- a/drivers/misc/Makefile +++ b/drivers/misc/Makefile @@ -4,6 +4,7 @@ # obj-$(CONFIG_IBM_ASM) += ibmasm/ +obj-$(CONFIG_IBMVMC) += ibmvmc.o obj-$(CONFIG_AD525X_DPOT) += ad525x_dpot.o obj-$(CONFIG_AD525X_DPOT_I2C) += ad525x_dpot-i2c.o obj-$(CONFIG_AD525X_DPOT_SPI) += ad525x_dpot-spi.o diff --git a/drivers/misc/ibmvmc.c b/drivers/misc/ibmvmc.c new file mode 100644 index 000000000000..fb83d1375638 --- /dev/null +++ b/drivers/misc/ibmvmc.c @@ -0,0 +1,2418 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * IBM Power Systems Virtual Management Channel Support. + * + * Copyright (c) 2004, 2018 IBM Corp. + * Dave Engebretsen engebret@us.ibm.com + * Steven Royer seroyer@linux.vnet.ibm.com + * Adam Reznechek adreznec@linux.vnet.ibm.com + * Bryant G. Ly + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include +#include +#include + +#include "ibmvmc.h" + +#define IBMVMC_DRIVER_VERSION "1.0" + +/* + * Static global variables + */ +static DECLARE_WAIT_QUEUE_HEAD(ibmvmc_read_wait); + +static const char ibmvmc_driver_name[] = "ibmvmc"; + +static struct ibmvmc_struct ibmvmc; +static struct ibmvmc_hmc hmcs[MAX_HMCS]; +static struct crq_server_adapter ibmvmc_adapter; + +static int ibmvmc_max_buf_pool_size = DEFAULT_BUF_POOL_SIZE; +static int ibmvmc_max_hmcs = DEFAULT_HMCS; +static int ibmvmc_max_mtu = DEFAULT_MTU; + +static inline long h_copy_rdma(s64 length, u64 sliobn, u64 slioba, + u64 dliobn, u64 dlioba) +{ + long rc = 0; + + /* Ensure all writes to source memory are visible before hcall */ + dma_wmb(); + pr_debug("ibmvmc: h_copy_rdma(0x%llx, 0x%llx, 0x%llx, 0x%llx, 0x%llx\n", + length, sliobn, slioba, dliobn, dlioba); + rc = plpar_hcall_norets(H_COPY_RDMA, length, sliobn, slioba, + dliobn, dlioba); + pr_debug("ibmvmc: h_copy_rdma rc = 0x%lx\n", rc); + + return rc; +} + +static inline void h_free_crq(uint32_t unit_address) +{ + long rc = 0; + + do { + if (H_IS_LONG_BUSY(rc)) + msleep(get_longbusy_msecs(rc)); + + rc = plpar_hcall_norets(H_FREE_CRQ, unit_address); + } while ((rc == H_BUSY) || (H_IS_LONG_BUSY(rc))); +} + +/** + * h_request_vmc: - request a hypervisor virtual management channel device + * @vmc_index: drc index of the vmc device created + * + * Requests the hypervisor create a new virtual management channel device, + * allowing this partition to send hypervisor virtualization control + * commands. + * + * Return: + * 0 - Success + * Non-zero - Failure + */ +static inline long h_request_vmc(u32 *vmc_index) +{ + long rc = 0; + unsigned long retbuf[PLPAR_HCALL_BUFSIZE]; + + do { + if (H_IS_LONG_BUSY(rc)) + msleep(get_longbusy_msecs(rc)); + + /* Call to request the VMC device from phyp */ + rc = plpar_hcall(H_REQUEST_VMC, retbuf); + pr_debug("ibmvmc: %s rc = 0x%lx\n", __func__, rc); + *vmc_index = retbuf[0]; + } while ((rc == H_BUSY) || (H_IS_LONG_BUSY(rc))); + + return rc; +} + +/* routines for managing a command/response queue */ +/** + * ibmvmc_handle_event: - Interrupt handler for crq events + * @irq: number of irq to handle, not used + * @dev_instance: crq_server_adapter that received interrupt + * + * Disables interrupts and schedules ibmvmc_task + * + * Always returns IRQ_HANDLED + */ +static irqreturn_t ibmvmc_handle_event(int irq, void *dev_instance) +{ + struct crq_server_adapter *adapter = + (struct crq_server_adapter *)dev_instance; + + vio_disable_interrupts(to_vio_dev(adapter->dev)); + tasklet_schedule(&adapter->work_task); + + return IRQ_HANDLED; +} + +/** + * ibmvmc_release_crq_queue - Release CRQ Queue + * + * @adapter: crq_server_adapter struct + * + * Return: + * 0 - Success + * Non-Zero - Failure + */ +static void ibmvmc_release_crq_queue(struct crq_server_adapter *adapter) +{ + struct vio_dev *vdev = to_vio_dev(adapter->dev); + struct crq_queue *queue = &adapter->queue; + + free_irq(vdev->irq, (void *)adapter); + tasklet_kill(&adapter->work_task); + + if (adapter->reset_task) + kthread_stop(adapter->reset_task); + + h_free_crq(vdev->unit_address); + dma_unmap_single(adapter->dev, + queue->msg_token, + queue->size * sizeof(*queue->msgs), DMA_BIDIRECTIONAL); + free_page((unsigned long)queue->msgs); +} + +/** + * ibmvmc_reset_crq_queue - Reset CRQ Queue + * + * @adapter: crq_server_adapter struct + * + * This function calls h_free_crq and then calls H_REG_CRQ and does all the + * bookkeeping to get us back to where we can communicate. + * + * Return: + * 0 - Success + * Non-Zero - Failure + */ +static int ibmvmc_reset_crq_queue(struct crq_server_adapter *adapter) +{ + struct vio_dev *vdev = to_vio_dev(adapter->dev); + struct crq_queue *queue = &adapter->queue; + int rc = 0; + + /* Close the CRQ */ + h_free_crq(vdev->unit_address); + + /* Clean out the queue */ + memset(queue->msgs, 0x00, PAGE_SIZE); + queue->cur = 0; + + /* And re-open it again */ + rc = plpar_hcall_norets(H_REG_CRQ, + vdev->unit_address, + queue->msg_token, PAGE_SIZE); + if (rc == 2) + /* Adapter is good, but other end is not ready */ + dev_warn(adapter->dev, "Partner adapter not ready\n"); + else if (rc != 0) + dev_err(adapter->dev, "couldn't register crq--rc 0x%x\n", rc); + + return rc; +} + +/** + * crq_queue_next_crq: - Returns the next entry in message queue + * @queue: crq_queue to use + * + * Returns pointer to next entry in queue, or NULL if there are no new + * entried in the CRQ. + */ +static struct ibmvmc_crq_msg *crq_queue_next_crq(struct crq_queue *queue) +{ + struct ibmvmc_crq_msg *crq; + unsigned long flags; + + spin_lock_irqsave(&queue->lock, flags); + crq = &queue->msgs[queue->cur]; + if (crq->valid & 0x80) { + if (++queue->cur == queue->size) + queue->cur = 0; + + /* Ensure the read of the valid bit occurs before reading any + * other bits of the CRQ entry + */ + dma_rmb(); + } else { + crq = NULL; + } + + spin_unlock_irqrestore(&queue->lock, flags); + + return crq; +} + +/** + * ibmvmc_send_crq - Send CRQ + * + * @adapter: crq_server_adapter struct + * @word1: Word1 Data field + * @word2: Word2 Data field + * + * Return: + * 0 - Success + * Non-Zero - Failure + */ +static long ibmvmc_send_crq(struct crq_server_adapter *adapter, + u64 word1, u64 word2) +{ + struct vio_dev *vdev = to_vio_dev(adapter->dev); + long rc = 0; + + dev_dbg(adapter->dev, "(0x%x, 0x%016llx, 0x%016llx)\n", + vdev->unit_address, word1, word2); + + /* + * Ensure the command buffer is flushed to memory before handing it + * over to the other side to prevent it from fetching any stale data. + */ + dma_wmb(); + rc = plpar_hcall_norets(H_SEND_CRQ, vdev->unit_address, word1, word2); + dev_dbg(adapter->dev, "rc = 0x%lx\n", rc); + + return rc; +} + +/** + * alloc_dma_buffer - Create DMA Buffer + * + * @vdev: vio_dev struct + * @size: Size field + * @dma_handle: DMA address field + * + * Allocates memory for the command queue and maps remote memory into an + * ioba. + * + * Returns a pointer to the buffer + */ +static void *alloc_dma_buffer(struct vio_dev *vdev, size_t size, + dma_addr_t *dma_handle) +{ + /* allocate memory */ + void *buffer = kzalloc(size, GFP_KERNEL); + + if (!buffer) { + *dma_handle = 0; + return NULL; + } + + /* DMA map */ + *dma_handle = dma_map_single(&vdev->dev, buffer, size, + DMA_BIDIRECTIONAL); + + if (dma_mapping_error(&vdev->dev, *dma_handle)) { + *dma_handle = 0; + kzfree(buffer); + return NULL; + } + + return buffer; +} + +/** + * free_dma_buffer - Free DMA Buffer + * + * @vdev: vio_dev struct + * @size: Size field + * @vaddr: Address field + * @dma_handle: DMA address field + * + * Releases memory for a command queue and unmaps mapped remote memory. + */ +static void free_dma_buffer(struct vio_dev *vdev, size_t size, void *vaddr, + dma_addr_t dma_handle) +{ + /* DMA unmap */ + dma_unmap_single(&vdev->dev, dma_handle, size, DMA_BIDIRECTIONAL); + + /* deallocate memory */ + kzfree(vaddr); +} + +/** + * ibmvmc_get_valid_hmc_buffer - Retrieve Valid HMC Buffer + * + * @hmc_index: HMC Index Field + * + * Return: + * Pointer to ibmvmc_buffer + */ +static struct ibmvmc_buffer *ibmvmc_get_valid_hmc_buffer(u8 hmc_index) +{ + struct ibmvmc_buffer *buffer; + struct ibmvmc_buffer *ret_buf = NULL; + unsigned long i; + + if (hmc_index > ibmvmc.max_hmc_index) + return NULL; + + buffer = hmcs[hmc_index].buffer; + + for (i = 0; i < ibmvmc_max_buf_pool_size; i++) { + if (buffer[i].valid && buffer[i].free && + buffer[i].owner == VMC_BUF_OWNER_ALPHA) { + buffer[i].free = 0; + ret_buf = &buffer[i]; + break; + } + } + + return ret_buf; +} + +/** + * ibmvmc_get_free_hmc_buffer - Get Free HMC Buffer + * + * @adapter: crq_server_adapter struct + * @hmc_index: Hmc Index field + * + * Return: + * Pointer to ibmvmc_buffer + */ +static struct ibmvmc_buffer *ibmvmc_get_free_hmc_buffer(struct crq_server_adapter *adapter, + u8 hmc_index) +{ + struct ibmvmc_buffer *buffer; + struct ibmvmc_buffer *ret_buf = NULL; + unsigned long i; + + if (hmc_index > ibmvmc.max_hmc_index) { + dev_info(adapter->dev, "get_free_hmc_buffer: invalid hmc_index=0x%x\n", + hmc_index); + return NULL; + } + + buffer = hmcs[hmc_index].buffer; + + for (i = 0; i < ibmvmc_max_buf_pool_size; i++) { + if (buffer[i].free && + buffer[i].owner == VMC_BUF_OWNER_ALPHA) { + buffer[i].free = 0; + ret_buf = &buffer[i]; + break; + } + } + + return ret_buf; +} + +/** + * ibmvmc_free_hmc_buffer - Free an HMC Buffer + * + * @hmc: ibmvmc_hmc struct + * @buffer: ibmvmc_buffer struct + * + */ +static void ibmvmc_free_hmc_buffer(struct ibmvmc_hmc *hmc, + struct ibmvmc_buffer *buffer) +{ + unsigned long flags; + + spin_lock_irqsave(&hmc->lock, flags); + buffer->free = 1; + spin_unlock_irqrestore(&hmc->lock, flags); +} + +/** + * ibmvmc_count_hmc_buffers - Count HMC Buffers + * + * @hmc_index: HMC Index field + * @valid: Valid number of buffers field + * @free: Free number of buffers field + * + */ +static void ibmvmc_count_hmc_buffers(u8 hmc_index, unsigned int *valid, + unsigned int *free) +{ + struct ibmvmc_buffer *buffer; + unsigned long i; + unsigned long flags; + + if (hmc_index > ibmvmc.max_hmc_index) + return; + + if (!valid || !free) + return; + + *valid = 0; *free = 0; + + buffer = hmcs[hmc_index].buffer; + spin_lock_irqsave(&hmcs[hmc_index].lock, flags); + + for (i = 0; i < ibmvmc_max_buf_pool_size; i++) { + if (buffer[i].valid) { + *valid = *valid + 1; + if (buffer[i].free) + *free = *free + 1; + } + } + + spin_unlock_irqrestore(&hmcs[hmc_index].lock, flags); +} + +/** + * ibmvmc_get_free_hmc - Get Free HMC + * + * Return: + * Pointer to an available HMC Connection + * Null otherwise + */ +static struct ibmvmc_hmc *ibmvmc_get_free_hmc(void) +{ + unsigned long i; + unsigned long flags; + + /* + * Find an available HMC connection. + */ + for (i = 0; i <= ibmvmc.max_hmc_index; i++) { + spin_lock_irqsave(&hmcs[i].lock, flags); + if (hmcs[i].state == ibmhmc_state_free) { + hmcs[i].index = i; + hmcs[i].state = ibmhmc_state_initial; + spin_unlock_irqrestore(&hmcs[i].lock, flags); + return &hmcs[i]; + } + spin_unlock_irqrestore(&hmcs[i].lock, flags); + } + + return NULL; +} + +/** + * ibmvmc_return_hmc - Return an HMC Connection + * + * @hmc: ibmvmc_hmc struct + * @release_readers: Number of readers connected to session + * + * This function releases the HMC connections back into the pool. + * + * Return: + * 0 - Success + * Non-zero - Failure + */ +static int ibmvmc_return_hmc(struct ibmvmc_hmc *hmc, bool release_readers) +{ + struct ibmvmc_buffer *buffer; + struct crq_server_adapter *adapter; + struct vio_dev *vdev; + unsigned long i; + unsigned long flags; + + if (!hmc || !hmc->adapter) + return -EIO; + + if (release_readers) { + if (hmc->file_session) { + struct ibmvmc_file_session *session = hmc->file_session; + + session->valid = 0; + wake_up_interruptible(&ibmvmc_read_wait); + } + } + + adapter = hmc->adapter; + vdev = to_vio_dev(adapter->dev); + + spin_lock_irqsave(&hmc->lock, flags); + hmc->index = 0; + hmc->state = ibmhmc_state_free; + hmc->queue_head = 0; + hmc->queue_tail = 0; + buffer = hmc->buffer; + for (i = 0; i < ibmvmc_max_buf_pool_size; i++) { + if (buffer[i].valid) { + free_dma_buffer(vdev, + ibmvmc.max_mtu, + buffer[i].real_addr_local, + buffer[i].dma_addr_local); + dev_dbg(adapter->dev, "Forgot buffer id 0x%lx\n", i); + } + memset(&buffer[i], 0, sizeof(struct ibmvmc_buffer)); + + hmc->queue_outbound_msgs[i] = VMC_INVALID_BUFFER_ID; + } + + spin_unlock_irqrestore(&hmc->lock, flags); + + return 0; +} + +/** + * ibmvmc_send_open - Interface Open + * @buffer: Pointer to ibmvmc_buffer struct + * @hmc: Pointer to ibmvmc_hmc struct + * + * This command is sent by the management partition as the result of a + * management partition device request. It causes the hypervisor to + * prepare a set of data buffers for the management application connection + * indicated HMC idx. A unique HMC Idx would be used if multiple management + * applications running concurrently were desired. Before responding to this + * command, the hypervisor must provide the management partition with at + * least one of these new buffers via the Add Buffer. This indicates whether + * the messages are inbound or outbound from the hypervisor. + * + * Return: + * 0 - Success + * Non-zero - Failure + */ +static int ibmvmc_send_open(struct ibmvmc_buffer *buffer, + struct ibmvmc_hmc *hmc) +{ + struct ibmvmc_crq_msg crq_msg; + struct crq_server_adapter *adapter; + __be64 *crq_as_u64 = (__be64 *)&crq_msg; + int rc = 0; + + if (!hmc || !hmc->adapter) + return -EIO; + + adapter = hmc->adapter; + + dev_dbg(adapter->dev, "send_open: 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx\n", + (unsigned long)buffer->size, (unsigned long)adapter->liobn, + (unsigned long)buffer->dma_addr_local, + (unsigned long)adapter->riobn, + (unsigned long)buffer->dma_addr_remote); + + rc = h_copy_rdma(buffer->size, + adapter->liobn, + buffer->dma_addr_local, + adapter->riobn, + buffer->dma_addr_remote); + if (rc) { + dev_err(adapter->dev, "Error: In send_open, h_copy_rdma rc 0x%x\n", + rc); + return -EIO; + } + + hmc->state = ibmhmc_state_opening; + + crq_msg.valid = 0x80; + crq_msg.type = VMC_MSG_OPEN; + crq_msg.status = 0; + crq_msg.var1.rsvd = 0; + crq_msg.hmc_session = hmc->session; + crq_msg.hmc_index = hmc->index; + crq_msg.var2.buffer_id = cpu_to_be16(buffer->id); + crq_msg.rsvd = 0; + crq_msg.var3.rsvd = 0; + + ibmvmc_send_crq(adapter, be64_to_cpu(crq_as_u64[0]), + be64_to_cpu(crq_as_u64[1])); + + return rc; +} + +/** + * ibmvmc_send_close - Interface Close + * @hmc: Pointer to ibmvmc_hmc struct + * + * This command is sent by the management partition to terminate a + * management application to hypervisor connection. When this command is + * sent, the management partition has quiesced all I/O operations to all + * buffers associated with this management application connection, and + * has freed any storage for these buffers. + * + * Return: + * 0 - Success + * Non-zero - Failure + */ +static int ibmvmc_send_close(struct ibmvmc_hmc *hmc) +{ + struct ibmvmc_crq_msg crq_msg; + struct crq_server_adapter *adapter; + __be64 *crq_as_u64 = (__be64 *)&crq_msg; + int rc = 0; + + if (!hmc || !hmc->adapter) + return -EIO; + + adapter = hmc->adapter; + + dev_info(adapter->dev, "CRQ send: close\n"); + + crq_msg.valid = 0x80; + crq_msg.type = VMC_MSG_CLOSE; + crq_msg.status = 0; + crq_msg.var1.rsvd = 0; + crq_msg.hmc_session = hmc->session; + crq_msg.hmc_index = hmc->index; + crq_msg.var2.rsvd = 0; + crq_msg.rsvd = 0; + crq_msg.var3.rsvd = 0; + + ibmvmc_send_crq(adapter, be64_to_cpu(crq_as_u64[0]), + be64_to_cpu(crq_as_u64[1])); + + return rc; +} + +/** + * ibmvmc_send_capabilities - Send VMC Capabilities + * + * @adapter: crq_server_adapter struct + * + * The capabilities message is an administrative message sent after the CRQ + * initialization sequence of messages and is used to exchange VMC capabilities + * between the management partition and the hypervisor. The management + * partition must send this message and the hypervisor must respond with VMC + * capabilities Response message before HMC interface message can begin. Any + * HMC interface messages received before the exchange of capabilities has + * complete are dropped. + * + * Return: + * 0 - Success + */ +static int ibmvmc_send_capabilities(struct crq_server_adapter *adapter) +{ + struct ibmvmc_admin_crq_msg crq_msg; + __be64 *crq_as_u64 = (__be64 *)&crq_msg; + + dev_dbg(adapter->dev, "ibmvmc: CRQ send: capabilities\n"); + crq_msg.valid = 0x80; + crq_msg.type = VMC_MSG_CAP; + crq_msg.status = 0; + crq_msg.rsvd[0] = 0; + crq_msg.rsvd[1] = 0; + crq_msg.max_hmc = ibmvmc_max_hmcs; + crq_msg.max_mtu = cpu_to_be32(ibmvmc_max_mtu); + crq_msg.pool_size = cpu_to_be16(ibmvmc_max_buf_pool_size); + crq_msg.crq_size = cpu_to_be16(adapter->queue.size); + crq_msg.version = cpu_to_be16(IBMVMC_PROTOCOL_VERSION); + + ibmvmc_send_crq(adapter, be64_to_cpu(crq_as_u64[0]), + be64_to_cpu(crq_as_u64[1])); + + ibmvmc.state = ibmvmc_state_capabilities; + + return 0; +} + +/** + * ibmvmc_send_add_buffer_resp - Add Buffer Response + * + * @adapter: crq_server_adapter struct + * @status: Status field + * @hmc_session: HMC Session field + * @hmc_index: HMC Index field + * @buffer_id: Buffer Id field + * + * This command is sent by the management partition to the hypervisor in + * response to the Add Buffer message. The Status field indicates the result of + * the command. + * + * Return: + * 0 - Success + */ +static int ibmvmc_send_add_buffer_resp(struct crq_server_adapter *adapter, + u8 status, u8 hmc_session, + u8 hmc_index, u16 buffer_id) +{ + struct ibmvmc_crq_msg crq_msg; + __be64 *crq_as_u64 = (__be64 *)&crq_msg; + + dev_dbg(adapter->dev, "CRQ send: add_buffer_resp\n"); + crq_msg.valid = 0x80; + crq_msg.type = VMC_MSG_ADD_BUF_RESP; + crq_msg.status = status; + crq_msg.var1.rsvd = 0; + crq_msg.hmc_session = hmc_session; + crq_msg.hmc_index = hmc_index; + crq_msg.var2.buffer_id = cpu_to_be16(buffer_id); + crq_msg.rsvd = 0; + crq_msg.var3.rsvd = 0; + + ibmvmc_send_crq(adapter, be64_to_cpu(crq_as_u64[0]), + be64_to_cpu(crq_as_u64[1])); + + return 0; +} + +/** + * ibmvmc_send_rem_buffer_resp - Remove Buffer Response + * + * @adapter: crq_server_adapter struct + * @status: Status field + * @hmc_session: HMC Session field + * @hmc_index: HMC Index field + * @buffer_id: Buffer Id field + * + * This command is sent by the management partition to the hypervisor in + * response to the Remove Buffer message. The Buffer ID field indicates + * which buffer the management partition selected to remove. The Status + * field indicates the result of the command. + * + * Return: + * 0 - Success + */ +static int ibmvmc_send_rem_buffer_resp(struct crq_server_adapter *adapter, + u8 status, u8 hmc_session, + u8 hmc_index, u16 buffer_id) +{ + struct ibmvmc_crq_msg crq_msg; + __be64 *crq_as_u64 = (__be64 *)&crq_msg; + + dev_dbg(adapter->dev, "CRQ send: rem_buffer_resp\n"); + crq_msg.valid = 0x80; + crq_msg.type = VMC_MSG_REM_BUF_RESP; + crq_msg.status = status; + crq_msg.var1.rsvd = 0; + crq_msg.hmc_session = hmc_session; + crq_msg.hmc_index = hmc_index; + crq_msg.var2.buffer_id = cpu_to_be16(buffer_id); + crq_msg.rsvd = 0; + crq_msg.var3.rsvd = 0; + + ibmvmc_send_crq(adapter, be64_to_cpu(crq_as_u64[0]), + be64_to_cpu(crq_as_u64[1])); + + return 0; +} + +/** + * ibmvmc_send_msg - Signal Message + * + * @adapter: crq_server_adapter struct + * @buffer: ibmvmc_buffer struct + * @hmc: ibmvmc_hmc struct + * @msg_length: message length field + * + * This command is sent between the management partition and the hypervisor + * in order to signal the arrival of an HMC protocol message. The command + * can be sent by both the management partition and the hypervisor. It is + * used for all traffic between the management application and the hypervisor, + * regardless of who initiated the communication. + * + * There is no response to this message. + * + * Return: + * 0 - Success + * Non-zero - Failure + */ +static int ibmvmc_send_msg(struct crq_server_adapter *adapter, + struct ibmvmc_buffer *buffer, + struct ibmvmc_hmc *hmc, int msg_len) +{ + struct ibmvmc_crq_msg crq_msg; + __be64 *crq_as_u64 = (__be64 *)&crq_msg; + int rc = 0; + + dev_dbg(adapter->dev, "CRQ send: rdma to HV\n"); + rc = h_copy_rdma(msg_len, + adapter->liobn, + buffer->dma_addr_local, + adapter->riobn, + buffer->dma_addr_remote); + if (rc) { + dev_err(adapter->dev, "Error in send_msg, h_copy_rdma rc 0x%x\n", + rc); + return rc; + } + + crq_msg.valid = 0x80; + crq_msg.type = VMC_MSG_SIGNAL; + crq_msg.status = 0; + crq_msg.var1.rsvd = 0; + crq_msg.hmc_session = hmc->session; + crq_msg.hmc_index = hmc->index; + crq_msg.var2.buffer_id = cpu_to_be16(buffer->id); + crq_msg.var3.msg_len = cpu_to_be32(msg_len); + dev_dbg(adapter->dev, "CRQ send: msg to HV 0x%llx 0x%llx\n", + be64_to_cpu(crq_as_u64[0]), be64_to_cpu(crq_as_u64[1])); + + buffer->owner = VMC_BUF_OWNER_HV; + ibmvmc_send_crq(adapter, be64_to_cpu(crq_as_u64[0]), + be64_to_cpu(crq_as_u64[1])); + + return rc; +} + +/** + * ibmvmc_open - Open Session + * + * @inode: inode struct + * @file: file struct + * + * Return: + * 0 - Success + */ +static int ibmvmc_open(struct inode *inode, struct file *file) +{ + struct ibmvmc_file_session *session; + int rc = 0; + + pr_debug("%s: inode = 0x%lx, file = 0x%lx, state = 0x%x\n", __func__, + (unsigned long)inode, (unsigned long)file, + ibmvmc.state); + + session = kzalloc(sizeof(*session), GFP_KERNEL); + session->file = file; + file->private_data = session; + + return rc; +} + +/** + * ibmvmc_close - Close Session + * + * @inode: inode struct + * @file: file struct + * + * Return: + * 0 - Success + * Non-zero - Failure + */ +static int ibmvmc_close(struct inode *inode, struct file *file) +{ + struct ibmvmc_file_session *session; + struct ibmvmc_hmc *hmc; + int rc = 0; + unsigned long flags; + + pr_debug("%s: file = 0x%lx, state = 0x%x\n", __func__, + (unsigned long)file, ibmvmc.state); + + session = file->private_data; + if (!session) + return -EIO; + + hmc = session->hmc; + if (hmc) { + if (!hmc->adapter) + return -EIO; + + if (ibmvmc.state == ibmvmc_state_failed) { + dev_warn(hmc->adapter->dev, "close: state_failed\n"); + return -EIO; + } + + spin_lock_irqsave(&hmc->lock, flags); + if (hmc->state >= ibmhmc_state_opening) { + rc = ibmvmc_send_close(hmc); + if (rc) + dev_warn(hmc->adapter->dev, "close: send_close failed.\n"); + } + spin_unlock_irqrestore(&hmc->lock, flags); + } + + kzfree(session); + + return rc; +} + +/** + * ibmvmc_read - Read + * + * @file: file struct + * @buf: Character buffer + * @nbytes: Size in bytes + * @ppos: Offset + * + * Return: + * 0 - Success + * Non-zero - Failure + */ +static ssize_t ibmvmc_read(struct file *file, char *buf, size_t nbytes, + loff_t *ppos) +{ + struct ibmvmc_file_session *session; + struct ibmvmc_hmc *hmc; + struct crq_server_adapter *adapter; + struct ibmvmc_buffer *buffer; + ssize_t n; + ssize_t retval = 0; + unsigned long flags; + DEFINE_WAIT(wait); + + pr_debug("ibmvmc: read: file = 0x%lx, buf = 0x%lx, nbytes = 0x%lx\n", + (unsigned long)file, (unsigned long)buf, + (unsigned long)nbytes); + + if (nbytes == 0) + return 0; + + if (nbytes > ibmvmc.max_mtu) { + pr_warn("ibmvmc: read: nbytes invalid 0x%x\n", + (unsigned int)nbytes); + return -EINVAL; + } + + session = file->private_data; + if (!session) { + pr_warn("ibmvmc: read: no session\n"); + return -EIO; + } + + hmc = session->hmc; + if (!hmc) { + pr_warn("ibmvmc: read: no hmc\n"); + return -EIO; + } + + adapter = hmc->adapter; + if (!adapter) { + pr_warn("ibmvmc: read: no adapter\n"); + return -EIO; + } + + do { + prepare_to_wait(&ibmvmc_read_wait, &wait, TASK_INTERRUPTIBLE); + + spin_lock_irqsave(&hmc->lock, flags); + if (hmc->queue_tail != hmc->queue_head) + /* Data is available */ + break; + + spin_unlock_irqrestore(&hmc->lock, flags); + + if (!session->valid) { + retval = -EBADFD; + goto out; + } + if (file->f_flags & O_NONBLOCK) { + retval = -EAGAIN; + goto out; + } + + schedule(); + + if (signal_pending(current)) { + retval = -ERESTARTSYS; + goto out; + } + } while (1); + + buffer = &(hmc->buffer[hmc->queue_outbound_msgs[hmc->queue_tail]]); + hmc->queue_tail++; + if (hmc->queue_tail == ibmvmc_max_buf_pool_size) + hmc->queue_tail = 0; + spin_unlock_irqrestore(&hmc->lock, flags); + + nbytes = min_t(size_t, nbytes, buffer->msg_len); + n = copy_to_user((void *)buf, buffer->real_addr_local, nbytes); + dev_dbg(adapter->dev, "read: copy to user nbytes = 0x%lx.\n", nbytes); + ibmvmc_free_hmc_buffer(hmc, buffer); + retval = nbytes; + + if (n) { + dev_warn(adapter->dev, "read: copy to user failed.\n"); + retval = -EFAULT; + } + + out: + finish_wait(&ibmvmc_read_wait, &wait); + dev_dbg(adapter->dev, "read: out %ld\n", retval); + return retval; +} + +/** + * ibmvmc_poll - Poll + * + * @file: file struct + * @wait: Poll Table + * + * Return: + * poll.h return values + */ +static unsigned int ibmvmc_poll(struct file *file, poll_table *wait) +{ + struct ibmvmc_file_session *session; + struct ibmvmc_hmc *hmc; + unsigned int mask = 0; + + session = file->private_data; + if (!session) + return 0; + + hmc = session->hmc; + if (!hmc) + return 0; + + poll_wait(file, &ibmvmc_read_wait, wait); + + if (hmc->queue_head != hmc->queue_tail) + mask |= POLLIN | POLLRDNORM; + + return mask; +} + +/** + * ibmvmc_write - Write + * + * @file: file struct + * @buf: Character buffer + * @count: Count field + * @ppos: Offset + * + * Return: + * 0 - Success + * Non-zero - Failure + */ +static ssize_t ibmvmc_write(struct file *file, const char *buffer, + size_t count, loff_t *ppos) +{ + struct ibmvmc_buffer *vmc_buffer; + struct ibmvmc_file_session *session; + struct crq_server_adapter *adapter; + struct ibmvmc_hmc *hmc; + unsigned char *buf; + unsigned long flags; + size_t bytes; + const char *p = buffer; + size_t c = count; + int ret = 0; + + session = file->private_data; + if (!session) + return -EIO; + + hmc = session->hmc; + if (!hmc) + return -EIO; + + spin_lock_irqsave(&hmc->lock, flags); + if (hmc->state == ibmhmc_state_free) { + /* HMC connection is not valid (possibly was reset under us). */ + ret = -EIO; + goto out; + } + + adapter = hmc->adapter; + if (!adapter) { + ret = -EIO; + goto out; + } + + if (count > ibmvmc.max_mtu) { + dev_warn(adapter->dev, "invalid buffer size 0x%lx\n", + (unsigned long)count); + ret = -EIO; + goto out; + } + + /* Waiting for the open resp message to the ioctl(1) - retry */ + if (hmc->state == ibmhmc_state_opening) { + ret = -EBUSY; + goto out; + } + + /* Make sure the ioctl() was called & the open msg sent, and that + * the HMC connection has not failed. + */ + if (hmc->state != ibmhmc_state_ready) { + ret = -EIO; + goto out; + } + + vmc_buffer = ibmvmc_get_valid_hmc_buffer(hmc->index); + if (!vmc_buffer) { + /* No buffer available for the msg send, or we have not yet + * completed the open/open_resp sequence. Retry until this is + * complete. + */ + ret = -EBUSY; + goto out; + } + if (!vmc_buffer->real_addr_local) { + dev_err(adapter->dev, "no buffer storage assigned\n"); + ret = -EIO; + goto out; + } + buf = vmc_buffer->real_addr_local; + + while (c > 0) { + bytes = min_t(size_t, c, vmc_buffer->size); + + bytes -= copy_from_user(buf, p, bytes); + if (!bytes) { + ret = -EFAULT; + goto out; + } + c -= bytes; + p += bytes; + } + if (p == buffer) + goto out; + + file->f_path.dentry->d_inode->i_mtime = current_time(file_inode(file)); + mark_inode_dirty(file->f_path.dentry->d_inode); + + dev_dbg(adapter->dev, "write: file = 0x%lx, count = 0x%lx\n", + (unsigned long)file, (unsigned long)count); + + ibmvmc_send_msg(adapter, vmc_buffer, hmc, count); + ret = p - buffer; + out: + spin_unlock_irqrestore(&hmc->lock, flags); + return (ssize_t)(ret); +} + +/** + * ibmvmc_setup_hmc - Setup the HMC + * + * @session: ibmvmc_file_session struct + * + * Return: + * 0 - Success + * Non-zero - Failure + */ +static long ibmvmc_setup_hmc(struct ibmvmc_file_session *session) +{ + struct ibmvmc_hmc *hmc; + unsigned int valid, free, index; + + if (ibmvmc.state == ibmvmc_state_failed) { + pr_warn("ibmvmc: Reserve HMC: state_failed\n"); + return -EIO; + } + + if (ibmvmc.state < ibmvmc_state_ready) { + pr_warn("ibmvmc: Reserve HMC: not state_ready\n"); + return -EAGAIN; + } + + /* Device is busy until capabilities have been exchanged and we + * have a generic buffer for each possible HMC connection. + */ + for (index = 0; index <= ibmvmc.max_hmc_index; index++) { + valid = 0; + ibmvmc_count_hmc_buffers(index, &valid, &free); + if (valid == 0) { + pr_warn("ibmvmc: buffers not ready for index %d\n", + index); + return -ENOBUFS; + } + } + + /* Get an hmc object, and transition to ibmhmc_state_initial */ + hmc = ibmvmc_get_free_hmc(); + if (!hmc) { + pr_warn("%s: free hmc not found\n", __func__); + return -EBUSY; + } + + hmc->session = hmc->session + 1; + if (hmc->session == 0xff) + hmc->session = 1; + + session->hmc = hmc; + hmc->adapter = &ibmvmc_adapter; + hmc->file_session = session; + session->valid = 1; + + return 0; +} + +/** + * ibmvmc_ioctl_sethmcid - IOCTL Set HMC ID + * + * @session: ibmvmc_file_session struct + * @new_hmc_id: HMC id field + * + * IOCTL command to setup the hmc id + * + * Return: + * 0 - Success + * Non-zero - Failure + */ +static long ibmvmc_ioctl_sethmcid(struct ibmvmc_file_session *session, + unsigned char __user *new_hmc_id) +{ + struct ibmvmc_hmc *hmc; + struct ibmvmc_buffer *buffer; + size_t bytes; + char print_buffer[HMC_ID_LEN + 1]; + unsigned long flags; + long rc = 0; + + /* Reserve HMC session */ + hmc = session->hmc; + if (!hmc) { + rc = ibmvmc_setup_hmc(session); + if (rc) + return rc; + + hmc = session->hmc; + if (!hmc) { + pr_err("ibmvmc: setup_hmc success but no hmc\n"); + return -EIO; + } + } + + if (hmc->state != ibmhmc_state_initial) { + pr_warn("ibmvmc: sethmcid: invalid state to send open 0x%x\n", + hmc->state); + return -EIO; + } + + bytes = copy_from_user(hmc->hmc_id, new_hmc_id, HMC_ID_LEN); + if (bytes) + return -EFAULT; + + /* Send Open Session command */ + spin_lock_irqsave(&hmc->lock, flags); + buffer = ibmvmc_get_valid_hmc_buffer(hmc->index); + spin_unlock_irqrestore(&hmc->lock, flags); + + if (!buffer || !buffer->real_addr_local) { + pr_warn("ibmvmc: sethmcid: no buffer available\n"); + return -EIO; + } + + /* Make sure buffer is NULL terminated before trying to print it */ + memset(print_buffer, 0, HMC_ID_LEN + 1); + strncpy(print_buffer, hmc->hmc_id, HMC_ID_LEN); + pr_info("ibmvmc: sethmcid: Set HMC ID: \"%s\"\n", print_buffer); + + memcpy(buffer->real_addr_local, hmc->hmc_id, HMC_ID_LEN); + /* RDMA over ID, send open msg, change state to ibmhmc_state_opening */ + rc = ibmvmc_send_open(buffer, hmc); + + return rc; +} + +/** + * ibmvmc_ioctl_query - IOCTL Query + * + * @session: ibmvmc_file_session struct + * @ret_struct: ibmvmc_query_struct + * + * Return: + * 0 - Success + * Non-zero - Failure + */ +static long ibmvmc_ioctl_query(struct ibmvmc_file_session *session, + struct ibmvmc_query_struct __user *ret_struct) +{ + struct ibmvmc_query_struct query_struct; + size_t bytes; + + memset(&query_struct, 0, sizeof(query_struct)); + query_struct.have_vmc = (ibmvmc.state > ibmvmc_state_initial); + query_struct.state = ibmvmc.state; + query_struct.vmc_drc_index = ibmvmc.vmc_drc_index; + + bytes = copy_to_user(ret_struct, &query_struct, + sizeof(query_struct)); + if (bytes) + return -EFAULT; + + return 0; +} + +/** + * ibmvmc_ioctl_requestvmc - IOCTL Request VMC + * + * @session: ibmvmc_file_session struct + * @ret_vmc_index: VMC Index + * + * Return: + * 0 - Success + * Non-zero - Failure + */ +static long ibmvmc_ioctl_requestvmc(struct ibmvmc_file_session *session, + u32 __user *ret_vmc_index) +{ + /* TODO: (adreznec) Add locking to control multiple process access */ + size_t bytes; + long rc; + u32 vmc_drc_index; + + /* Call to request the VMC device from phyp*/ + rc = h_request_vmc(&vmc_drc_index); + pr_debug("ibmvmc: requestvmc: H_REQUEST_VMC rc = 0x%lx\n", rc); + + if (rc == H_SUCCESS) { + rc = 0; + } else if (rc == H_FUNCTION) { + pr_err("ibmvmc: requestvmc: h_request_vmc not supported\n"); + return -EPERM; + } else if (rc == H_AUTHORITY) { + pr_err("ibmvmc: requestvmc: hypervisor denied vmc request\n"); + return -EPERM; + } else if (rc == H_HARDWARE) { + pr_err("ibmvmc: requestvmc: hypervisor hardware fault\n"); + return -EIO; + } else if (rc == H_RESOURCE) { + pr_err("ibmvmc: requestvmc: vmc resource unavailable\n"); + return -ENODEV; + } else if (rc == H_NOT_AVAILABLE) { + pr_err("ibmvmc: requestvmc: system cannot be vmc managed\n"); + return -EPERM; + } else if (rc == H_PARAMETER) { + pr_err("ibmvmc: requestvmc: invalid parameter\n"); + return -EINVAL; + } + + /* Success, set the vmc index in global struct */ + ibmvmc.vmc_drc_index = vmc_drc_index; + + bytes = copy_to_user(ret_vmc_index, &vmc_drc_index, + sizeof(*ret_vmc_index)); + if (bytes) { + pr_warn("ibmvmc: requestvmc: copy to user failed.\n"); + return -EFAULT; + } + return rc; +} + +/** + * ibmvmc_ioctl - IOCTL + * + * @session: ibmvmc_file_session struct + * @cmd: cmd field + * @arg: Argument field + * + * Return: + * 0 - Success + * Non-zero - Failure + */ +static long ibmvmc_ioctl(struct file *file, + unsigned int cmd, unsigned long arg) +{ + struct ibmvmc_file_session *session = file->private_data; + + pr_debug("ibmvmc: ioctl file=0x%lx, cmd=0x%x, arg=0x%lx, ses=0x%lx\n", + (unsigned long)file, cmd, arg, + (unsigned long)session); + + if (!session) { + pr_warn("ibmvmc: ioctl: no session\n"); + return -EIO; + } + + switch (cmd) { + case VMC_IOCTL_SETHMCID: + return ibmvmc_ioctl_sethmcid(session, + (unsigned char __user *)arg); + case VMC_IOCTL_QUERY: + return ibmvmc_ioctl_query(session, + (struct ibmvmc_query_struct __user *)arg); + case VMC_IOCTL_REQUESTVMC: + return ibmvmc_ioctl_requestvmc(session, + (unsigned int __user *)arg); + default: + pr_warn("ibmvmc: unknown ioctl 0x%x\n", cmd); + return -EINVAL; + } +} + +static const struct file_operations ibmvmc_fops = { + .owner = THIS_MODULE, + .read = ibmvmc_read, + .write = ibmvmc_write, + .poll = ibmvmc_poll, + .unlocked_ioctl = ibmvmc_ioctl, + .open = ibmvmc_open, + .release = ibmvmc_close, +}; + +/** + * ibmvmc_add_buffer - Add Buffer + * + * @adapter: crq_server_adapter struct + * @crq: ibmvmc_crq_msg struct + * + * This message transfers a buffer from hypervisor ownership to management + * partition ownership. The LIOBA is obtained from the virtual TCE table + * associated with the hypervisor side of the VMC device, and points to a + * buffer of size MTU (as established in the capabilities exchange). + * + * Typical flow for ading buffers: + * 1. A new management application connection is opened by the management + * partition. + * 2. The hypervisor assigns new buffers for the traffic associated with + * that connection. + * 3. The hypervisor sends VMC Add Buffer messages to the management + * partition, informing it of the new buffers. + * 4. The hypervisor sends an HMC protocol message (to the management + * application) notifying it of the new buffers. This informs the + * application that it has buffers available for sending HMC + * commands. + * + * Return: + * 0 - Success + * Non-zero - Failure + */ +static int ibmvmc_add_buffer(struct crq_server_adapter *adapter, + struct ibmvmc_crq_msg *crq) +{ + struct ibmvmc_buffer *buffer; + u8 hmc_index; + u8 hmc_session; + u16 buffer_id; + unsigned long flags; + int rc = 0; + + if (!crq) + return -1; + + hmc_session = crq->hmc_session; + hmc_index = crq->hmc_index; + buffer_id = be16_to_cpu(crq->var2.buffer_id); + + if (hmc_index > ibmvmc.max_hmc_index) { + dev_err(adapter->dev, "add_buffer: invalid hmc_index = 0x%x\n", + hmc_index); + ibmvmc_send_add_buffer_resp(adapter, VMC_MSG_INVALID_HMC_INDEX, + hmc_session, hmc_index, buffer_id); + return -1; + } + + if (buffer_id >= ibmvmc.max_buffer_pool_size) { + dev_err(adapter->dev, "add_buffer: invalid buffer_id = 0x%x\n", + buffer_id); + ibmvmc_send_add_buffer_resp(adapter, VMC_MSG_INVALID_BUFFER_ID, + hmc_session, hmc_index, buffer_id); + return -1; + } + + spin_lock_irqsave(&hmcs[hmc_index].lock, flags); + buffer = &hmcs[hmc_index].buffer[buffer_id]; + + if (buffer->real_addr_local || buffer->dma_addr_local) { + dev_warn(adapter->dev, "add_buffer: already allocated id = 0x%lx\n", + (unsigned long)buffer_id); + spin_unlock_irqrestore(&hmcs[hmc_index].lock, flags); + ibmvmc_send_add_buffer_resp(adapter, VMC_MSG_INVALID_BUFFER_ID, + hmc_session, hmc_index, buffer_id); + return -1; + } + + buffer->real_addr_local = alloc_dma_buffer(to_vio_dev(adapter->dev), + ibmvmc.max_mtu, + &buffer->dma_addr_local); + + if (!buffer->real_addr_local) { + dev_err(adapter->dev, "add_buffer: alloc_dma_buffer failed.\n"); + spin_unlock_irqrestore(&hmcs[hmc_index].lock, flags); + ibmvmc_send_add_buffer_resp(adapter, VMC_MSG_INTERFACE_FAILURE, + hmc_session, hmc_index, buffer_id); + return -1; + } + + buffer->dma_addr_remote = be32_to_cpu(crq->var3.lioba); + buffer->size = ibmvmc.max_mtu; + buffer->owner = crq->var1.owner; + buffer->free = 1; + /* Must ensure valid==1 is observable only after all other fields are */ + dma_wmb(); + buffer->valid = 1; + buffer->id = buffer_id; + + dev_dbg(adapter->dev, "add_buffer: successfully added a buffer:\n"); + dev_dbg(adapter->dev, " index: %d, session: %d, buffer: 0x%x, owner: %d\n", + hmc_index, hmc_session, buffer_id, buffer->owner); + dev_dbg(adapter->dev, " local: 0x%x, remote: 0x%x\n", + (u32)buffer->dma_addr_local, + (u32)buffer->dma_addr_remote); + spin_unlock_irqrestore(&hmcs[hmc_index].lock, flags); + + ibmvmc_send_add_buffer_resp(adapter, VMC_MSG_SUCCESS, hmc_session, + hmc_index, buffer_id); + + return rc; +} + +/** + * ibmvmc_rem_buffer - Remove Buffer + * + * @adapter: crq_server_adapter struct + * @crq: ibmvmc_crq_msg struct + * + * This message requests an HMC buffer to be transferred from management + * partition ownership to hypervisor ownership. The management partition may + * not be able to satisfy the request at a particular point in time if all its + * buffers are in use. The management partition requires a depth of at least + * one inbound buffer to allow management application commands to flow to the + * hypervisor. It is, therefore, an interface error for the hypervisor to + * attempt to remove the management partition's last buffer. + * + * The hypervisor is expected to manage buffer usage with the management + * application directly and inform the management partition when buffers may be + * removed. The typical flow for removing buffers: + * + * 1. The management application no longer needs a communication path to a + * particular hypervisor function. That function is closed. + * 2. The hypervisor and the management application quiesce all traffic to that + * function. The hypervisor requests a reduction in buffer pool size. + * 3. The management application acknowledges the reduction in buffer pool size. + * 4. The hypervisor sends a Remove Buffer message to the management partition, + * informing it of the reduction in buffers. + * 5. The management partition verifies it can remove the buffer. This is + * possible if buffers have been quiesced. + * + * Return: + * 0 - Success + * Non-zero - Failure + */ +/* + * The hypervisor requested that we pick an unused buffer, and return it. + * Before sending the buffer back, we free any storage associated with the + * buffer. + */ +static int ibmvmc_rem_buffer(struct crq_server_adapter *adapter, + struct ibmvmc_crq_msg *crq) +{ + struct ibmvmc_buffer *buffer; + u8 hmc_index; + u8 hmc_session; + u16 buffer_id = 0; + unsigned long flags; + int rc = 0; + + if (!crq) + return -1; + + hmc_session = crq->hmc_session; + hmc_index = crq->hmc_index; + + if (hmc_index > ibmvmc.max_hmc_index) { + dev_warn(adapter->dev, "rem_buffer: invalid hmc_index = 0x%x\n", + hmc_index); + ibmvmc_send_rem_buffer_resp(adapter, VMC_MSG_INVALID_HMC_INDEX, + hmc_session, hmc_index, buffer_id); + return -1; + } + + spin_lock_irqsave(&hmcs[hmc_index].lock, flags); + buffer = ibmvmc_get_free_hmc_buffer(adapter, hmc_index); + if (!buffer) { + dev_info(adapter->dev, "rem_buffer: no buffer to remove\n"); + spin_unlock_irqrestore(&hmcs[hmc_index].lock, flags); + ibmvmc_send_rem_buffer_resp(adapter, VMC_MSG_NO_BUFFER, + hmc_session, hmc_index, + VMC_INVALID_BUFFER_ID); + return -1; + } + + buffer_id = buffer->id; + + if (buffer->valid) + free_dma_buffer(to_vio_dev(adapter->dev), + ibmvmc.max_mtu, + buffer->real_addr_local, + buffer->dma_addr_local); + + memset(buffer, 0, sizeof(struct ibmvmc_buffer)); + spin_unlock_irqrestore(&hmcs[hmc_index].lock, flags); + + dev_dbg(adapter->dev, "rem_buffer: removed buffer 0x%x.\n", buffer_id); + ibmvmc_send_rem_buffer_resp(adapter, VMC_MSG_SUCCESS, hmc_session, + hmc_index, buffer_id); + + return rc; +} + +static int ibmvmc_recv_msg(struct crq_server_adapter *adapter, + struct ibmvmc_crq_msg *crq) +{ + struct ibmvmc_buffer *buffer; + struct ibmvmc_hmc *hmc; + unsigned long msg_len; + u8 hmc_index; + u8 hmc_session; + u16 buffer_id; + unsigned long flags; + int rc = 0; + + if (!crq) + return -1; + + /* Hypervisor writes CRQs directly into our memory in big endian */ + dev_dbg(adapter->dev, "Recv_msg: msg from HV 0x%016llx 0x%016llx\n", + be64_to_cpu(*((unsigned long *)crq)), + be64_to_cpu(*(((unsigned long *)crq) + 1))); + + hmc_session = crq->hmc_session; + hmc_index = crq->hmc_index; + buffer_id = be16_to_cpu(crq->var2.buffer_id); + msg_len = be32_to_cpu(crq->var3.msg_len); + + if (hmc_index > ibmvmc.max_hmc_index) { + dev_err(adapter->dev, "Recv_msg: invalid hmc_index = 0x%x\n", + hmc_index); + ibmvmc_send_add_buffer_resp(adapter, VMC_MSG_INVALID_HMC_INDEX, + hmc_session, hmc_index, buffer_id); + return -1; + } + + if (buffer_id >= ibmvmc.max_buffer_pool_size) { + dev_err(adapter->dev, "Recv_msg: invalid buffer_id = 0x%x\n", + buffer_id); + ibmvmc_send_add_buffer_resp(adapter, VMC_MSG_INVALID_BUFFER_ID, + hmc_session, hmc_index, buffer_id); + return -1; + } + + hmc = &hmcs[hmc_index]; + spin_lock_irqsave(&hmc->lock, flags); + + if (hmc->state == ibmhmc_state_free) { + dev_err(adapter->dev, "Recv_msg: invalid hmc state = 0x%x\n", + hmc->state); + /* HMC connection is not valid (possibly was reset under us). */ + spin_unlock_irqrestore(&hmc->lock, flags); + return -1; + } + + buffer = &hmc->buffer[buffer_id]; + + if (buffer->valid == 0 || buffer->owner == VMC_BUF_OWNER_ALPHA) { + dev_err(adapter->dev, "Recv_msg: not valid, or not HV. 0x%x 0x%x\n", + buffer->valid, buffer->owner); + spin_unlock_irqrestore(&hmc->lock, flags); + return -1; + } + + /* RDMA the data into the partition. */ + rc = h_copy_rdma(msg_len, + adapter->riobn, + buffer->dma_addr_remote, + adapter->liobn, + buffer->dma_addr_local); + + dev_dbg(adapter->dev, "Recv_msg: msg_len = 0x%x, buffer_id = 0x%x, queue_head = 0x%x, hmc_idx = 0x%x\n", + (unsigned int)msg_len, (unsigned int)buffer_id, + (unsigned int)hmc->queue_head, (unsigned int)hmc_index); + buffer->msg_len = msg_len; + buffer->free = 0; + buffer->owner = VMC_BUF_OWNER_ALPHA; + + if (rc) { + dev_err(adapter->dev, "Failure in recv_msg: h_copy_rdma = 0x%x\n", + rc); + spin_unlock_irqrestore(&hmc->lock, flags); + return -1; + } + + /* Must be locked because read operates on the same data */ + hmc->queue_outbound_msgs[hmc->queue_head] = buffer_id; + hmc->queue_head++; + if (hmc->queue_head == ibmvmc_max_buf_pool_size) + hmc->queue_head = 0; + + if (hmc->queue_head == hmc->queue_tail) + dev_err(adapter->dev, "outbound buffer queue wrapped.\n"); + + spin_unlock_irqrestore(&hmc->lock, flags); + + wake_up_interruptible(&ibmvmc_read_wait); + + return 0; +} + +/** + * ibmvmc_process_capabilities - Process Capabilities + * + * @adapter: crq_server_adapter struct + * @crqp: ibmvmc_crq_msg struct + * + */ +static void ibmvmc_process_capabilities(struct crq_server_adapter *adapter, + struct ibmvmc_crq_msg *crqp) +{ + struct ibmvmc_admin_crq_msg *crq = (struct ibmvmc_admin_crq_msg *)crqp; + + if ((be16_to_cpu(crq->version) >> 8) != + (IBMVMC_PROTOCOL_VERSION >> 8)) { + dev_err(adapter->dev, "init failed, incompatible versions 0x%x 0x%x\n", + be16_to_cpu(crq->version), + IBMVMC_PROTOCOL_VERSION); + ibmvmc.state = ibmvmc_state_failed; + return; + } + + ibmvmc.max_mtu = min_t(u32, ibmvmc_max_mtu, be32_to_cpu(crq->max_mtu)); + ibmvmc.max_buffer_pool_size = min_t(u16, ibmvmc_max_buf_pool_size, + be16_to_cpu(crq->pool_size)); + ibmvmc.max_hmc_index = min_t(u8, ibmvmc_max_hmcs, crq->max_hmc) - 1; + ibmvmc.state = ibmvmc_state_ready; + + dev_info(adapter->dev, "Capabilities: mtu=0x%x, pool_size=0x%x, max_hmc=0x%x\n", + ibmvmc.max_mtu, ibmvmc.max_buffer_pool_size, + ibmvmc.max_hmc_index); +} + +/** + * ibmvmc_validate_hmc_session - Validate HMC Session + * + * @adapter: crq_server_adapter struct + * @crq: ibmvmc_crq_msg struct + * + * Return: + * 0 - Success + * Non-zero - Failure + */ +static int ibmvmc_validate_hmc_session(struct crq_server_adapter *adapter, + struct ibmvmc_crq_msg *crq) +{ + unsigned char hmc_index; + + hmc_index = crq->hmc_index; + + if (crq->hmc_session == 0) + return 0; + + if (hmc_index > ibmvmc.max_hmc_index) + return -1; + + if (hmcs[hmc_index].session != crq->hmc_session) { + dev_warn(adapter->dev, "Drop, bad session: expected 0x%x, recv 0x%x\n", + hmcs[hmc_index].session, crq->hmc_session); + return -1; + } + + return 0; +} + +/** + * ibmvmc_reset - Reset + * + * @adapter: crq_server_adapter struct + * @xport_event: export_event field + * + * Closes all HMC sessions and conditionally schedules a CRQ reset. + * @xport_event: If true, the partner closed their CRQ; we don't need to reset. + * If false, we need to schedule a CRQ reset. + */ +static void ibmvmc_reset(struct crq_server_adapter *adapter, bool xport_event) +{ + int i; + + if (ibmvmc.state != ibmvmc_state_sched_reset) { + dev_info(adapter->dev, "*** Reset to initial state.\n"); + for (i = 0; i < ibmvmc_max_hmcs; i++) + ibmvmc_return_hmc(&hmcs[i], xport_event); + + if (xport_event) { + /* CRQ was closed by the partner. We don't need to do + * anything except set ourself to the correct state to + * handle init msgs. + */ + ibmvmc.state = ibmvmc_state_crqinit; + } else { + /* The partner did not close their CRQ - instead, we're + * closing the CRQ on our end. Need to schedule this + * for process context, because CRQ reset may require a + * sleep. + * + * Setting ibmvmc.state here immediately prevents + * ibmvmc_open from completing until the reset + * completes in process context. + */ + ibmvmc.state = ibmvmc_state_sched_reset; + dev_dbg(adapter->dev, "Device reset scheduled"); + wake_up_interruptible(&adapter->reset_wait_queue); + } + } +} + +/** + * ibmvmc_reset_task - Reset Task + * + * @data: Data field + * + * Performs a CRQ reset of the VMC device in process context. + * NOTE: This function should not be called directly, use ibmvmc_reset. + */ +static int ibmvmc_reset_task(void *data) +{ + struct crq_server_adapter *adapter = data; + int rc; + + set_user_nice(current, -20); + + while (!kthread_should_stop()) { + wait_event_interruptible(adapter->reset_wait_queue, + (ibmvmc.state == ibmvmc_state_sched_reset) || + kthread_should_stop()); + + if (kthread_should_stop()) + break; + + dev_dbg(adapter->dev, "CRQ resetting in process context"); + tasklet_disable(&adapter->work_task); + + rc = ibmvmc_reset_crq_queue(adapter); + + if (rc != H_SUCCESS && rc != H_RESOURCE) { + dev_err(adapter->dev, "Error initializing CRQ. rc = 0x%x\n", + rc); + ibmvmc.state = ibmvmc_state_failed; + } else { + ibmvmc.state = ibmvmc_state_crqinit; + + if (ibmvmc_send_crq(adapter, 0xC001000000000000LL, 0) + != 0 && rc != H_RESOURCE) + dev_warn(adapter->dev, "Failed to send initialize CRQ message\n"); + } + + vio_enable_interrupts(to_vio_dev(adapter->dev)); + tasklet_enable(&adapter->work_task); + } + + return 0; +} + +/** + * ibmvmc_process_open_resp - Process Open Response + * + * @crq: ibmvmc_crq_msg struct + * @adapter: crq_server_adapter struct + * + * This command is sent by the hypervisor in response to the Interface + * Open message. When this message is received, the indicated buffer is + * again available for management partition use. + */ +static void ibmvmc_process_open_resp(struct ibmvmc_crq_msg *crq, + struct crq_server_adapter *adapter) +{ + unsigned char hmc_index; + unsigned short buffer_id; + + hmc_index = crq->hmc_index; + if (hmc_index > ibmvmc.max_hmc_index) { + /* Why would PHYP give an index > max negotiated? */ + ibmvmc_reset(adapter, false); + return; + } + + if (crq->status) { + dev_warn(adapter->dev, "open_resp: failed - status 0x%x\n", + crq->status); + ibmvmc_return_hmc(&hmcs[hmc_index], false); + return; + } + + if (hmcs[hmc_index].state == ibmhmc_state_opening) { + buffer_id = be16_to_cpu(crq->var2.buffer_id); + if (buffer_id >= ibmvmc.max_buffer_pool_size) { + dev_err(adapter->dev, "open_resp: invalid buffer_id = 0x%x\n", + buffer_id); + hmcs[hmc_index].state = ibmhmc_state_failed; + } else { + ibmvmc_free_hmc_buffer(&hmcs[hmc_index], + &hmcs[hmc_index].buffer[buffer_id]); + hmcs[hmc_index].state = ibmhmc_state_ready; + dev_dbg(adapter->dev, "open_resp: set hmc state = ready\n"); + } + } else { + dev_warn(adapter->dev, "open_resp: invalid hmc state (0x%x)\n", + hmcs[hmc_index].state); + } +} + +/** + * ibmvmc_process_close_resp - Process Close Response + * + * @crq: ibmvmc_crq_msg struct + * @adapter: crq_server_adapter struct + * + * This command is sent by the hypervisor in response to the managemant + * application Interface Close message. + * + * If the close fails, simply reset the entire driver as the state of the VMC + * must be in tough shape. + */ +static void ibmvmc_process_close_resp(struct ibmvmc_crq_msg *crq, + struct crq_server_adapter *adapter) +{ + unsigned char hmc_index; + + hmc_index = crq->hmc_index; + if (hmc_index > ibmvmc.max_hmc_index) { + ibmvmc_reset(adapter, false); + return; + } + + if (crq->status) { + dev_warn(adapter->dev, "close_resp: failed - status 0x%x\n", + crq->status); + ibmvmc_reset(adapter, false); + return; + } + + ibmvmc_return_hmc(&hmcs[hmc_index], false); +} + +/** + * ibmvmc_crq_process - Process CRQ + * + * @adapter: crq_server_adapter struct + * @crq: ibmvmc_crq_msg struct + * + * Process the CRQ message based upon the type of message received. + * + */ +static void ibmvmc_crq_process(struct crq_server_adapter *adapter, + struct ibmvmc_crq_msg *crq) +{ + switch (crq->type) { + case VMC_MSG_CAP_RESP: + dev_dbg(adapter->dev, "CRQ recv: capabilities resp (0x%x)\n", + crq->type); + if (ibmvmc.state == ibmvmc_state_capabilities) + ibmvmc_process_capabilities(adapter, crq); + else + dev_warn(adapter->dev, "caps msg invalid in state 0x%x\n", + ibmvmc.state); + break; + case VMC_MSG_OPEN_RESP: + dev_dbg(adapter->dev, "CRQ recv: open resp (0x%x)\n", + crq->type); + if (ibmvmc_validate_hmc_session(adapter, crq) == 0) + ibmvmc_process_open_resp(crq, adapter); + break; + case VMC_MSG_ADD_BUF: + dev_dbg(adapter->dev, "CRQ recv: add buf (0x%x)\n", + crq->type); + if (ibmvmc_validate_hmc_session(adapter, crq) == 0) + ibmvmc_add_buffer(adapter, crq); + break; + case VMC_MSG_REM_BUF: + dev_dbg(adapter->dev, "CRQ recv: rem buf (0x%x)\n", + crq->type); + if (ibmvmc_validate_hmc_session(adapter, crq) == 0) + ibmvmc_rem_buffer(adapter, crq); + break; + case VMC_MSG_SIGNAL: + dev_dbg(adapter->dev, "CRQ recv: signal msg (0x%x)\n", + crq->type); + if (ibmvmc_validate_hmc_session(adapter, crq) == 0) + ibmvmc_recv_msg(adapter, crq); + break; + case VMC_MSG_CLOSE_RESP: + dev_dbg(adapter->dev, "CRQ recv: close resp (0x%x)\n", + crq->type); + if (ibmvmc_validate_hmc_session(adapter, crq) == 0) + ibmvmc_process_close_resp(crq, adapter); + break; + case VMC_MSG_CAP: + case VMC_MSG_OPEN: + case VMC_MSG_CLOSE: + case VMC_MSG_ADD_BUF_RESP: + case VMC_MSG_REM_BUF_RESP: + dev_warn(adapter->dev, "CRQ recv: unexpected msg (0x%x)\n", + crq->type); + break; + default: + dev_warn(adapter->dev, "CRQ recv: unknown msg (0x%x)\n", + crq->type); + break; + } +} + +/** + * ibmvmc_handle_crq_init - Handle CRQ Init + * + * @crq: ibmvmc_crq_msg struct + * @adapter: crq_server_adapter struct + * + * Handle the type of crq initialization based on whether + * it is a message or a response. + * + */ +static void ibmvmc_handle_crq_init(struct ibmvmc_crq_msg *crq, + struct crq_server_adapter *adapter) +{ + switch (crq->type) { + case 0x01: /* Initialization message */ + dev_dbg(adapter->dev, "CRQ recv: CRQ init msg - state 0x%x\n", + ibmvmc.state); + if (ibmvmc.state == ibmvmc_state_crqinit) { + /* Send back a response */ + if (ibmvmc_send_crq(adapter, 0xC002000000000000, + 0) == 0) + ibmvmc_send_capabilities(adapter); + else + dev_err(adapter->dev, " Unable to send init rsp\n"); + } else { + dev_err(adapter->dev, "Invalid state 0x%x mtu = 0x%x\n", + ibmvmc.state, ibmvmc.max_mtu); + } + + break; + case 0x02: /* Initialization response */ + dev_dbg(adapter->dev, "CRQ recv: initialization resp msg - state 0x%x\n", + ibmvmc.state); + if (ibmvmc.state == ibmvmc_state_crqinit) + ibmvmc_send_capabilities(adapter); + break; + default: + dev_warn(adapter->dev, "Unknown crq message type 0x%lx\n", + (unsigned long)crq->type); + } +} + +/** + * ibmvmc_handle_crq - Handle CRQ + * + * @crq: ibmvmc_crq_msg struct + * @adapter: crq_server_adapter struct + * + * Read the command elements from the command queue and execute the + * requests based upon the type of crq message. + * + */ +static void ibmvmc_handle_crq(struct ibmvmc_crq_msg *crq, + struct crq_server_adapter *adapter) +{ + switch (crq->valid) { + case 0xC0: /* initialization */ + ibmvmc_handle_crq_init(crq, adapter); + break; + case 0xFF: /* Hypervisor telling us the connection is closed */ + dev_warn(adapter->dev, "CRQ recv: virtual adapter failed - resetting.\n"); + ibmvmc_reset(adapter, true); + break; + case 0x80: /* real payload */ + ibmvmc_crq_process(adapter, crq); + break; + default: + dev_warn(adapter->dev, "CRQ recv: unknown msg 0x%02x.\n", + crq->valid); + break; + } +} + +static void ibmvmc_task(unsigned long data) +{ + struct crq_server_adapter *adapter = + (struct crq_server_adapter *)data; + struct vio_dev *vdev = to_vio_dev(adapter->dev); + struct ibmvmc_crq_msg *crq; + int done = 0; + + while (!done) { + /* Pull all the valid messages off the CRQ */ + while ((crq = crq_queue_next_crq(&adapter->queue)) != NULL) { + ibmvmc_handle_crq(crq, adapter); + crq->valid = 0x00; + /* CRQ reset was requested, stop processing CRQs. + * Interrupts will be re-enabled by the reset task. + */ + if (ibmvmc.state == ibmvmc_state_sched_reset) + return; + } + + vio_enable_interrupts(vdev); + crq = crq_queue_next_crq(&adapter->queue); + if (crq) { + vio_disable_interrupts(vdev); + ibmvmc_handle_crq(crq, adapter); + crq->valid = 0x00; + /* CRQ reset was requested, stop processing CRQs. + * Interrupts will be re-enabled by the reset task. + */ + if (ibmvmc.state == ibmvmc_state_sched_reset) + return; + } else { + done = 1; + } + } +} + +/** + * ibmvmc_init_crq_queue - Init CRQ Queue + * + * @adapter: crq_server_adapter struct + * + * Return: + * 0 - Success + * Non-zero - Failure + */ +static int ibmvmc_init_crq_queue(struct crq_server_adapter *adapter) +{ + struct vio_dev *vdev = to_vio_dev(adapter->dev); + struct crq_queue *queue = &adapter->queue; + int rc = 0; + int retrc = 0; + + queue->msgs = (struct ibmvmc_crq_msg *)get_zeroed_page(GFP_KERNEL); + + if (!queue->msgs) + goto malloc_failed; + + queue->size = PAGE_SIZE / sizeof(*queue->msgs); + + queue->msg_token = dma_map_single(adapter->dev, queue->msgs, + queue->size * sizeof(*queue->msgs), + DMA_BIDIRECTIONAL); + + if (dma_mapping_error(adapter->dev, queue->msg_token)) + goto map_failed; + + retrc = plpar_hcall_norets(H_REG_CRQ, + vdev->unit_address, + queue->msg_token, PAGE_SIZE); + retrc = rc; + + if (rc == H_RESOURCE) + rc = ibmvmc_reset_crq_queue(adapter); + + if (rc == 2) { + dev_warn(adapter->dev, "Partner adapter not ready\n"); + retrc = 0; + } else if (rc != 0) { + dev_err(adapter->dev, "Error %d opening adapter\n", rc); + goto reg_crq_failed; + } + + queue->cur = 0; + spin_lock_init(&queue->lock); + + tasklet_init(&adapter->work_task, ibmvmc_task, (unsigned long)adapter); + + if (request_irq(vdev->irq, + ibmvmc_handle_event, + 0, "ibmvmc", (void *)adapter) != 0) { + dev_err(adapter->dev, "couldn't register irq 0x%x\n", + vdev->irq); + goto req_irq_failed; + } + + rc = vio_enable_interrupts(vdev); + if (rc != 0) { + dev_err(adapter->dev, "Error %d enabling interrupts!!!\n", rc); + goto req_irq_failed; + } + + return retrc; + +req_irq_failed: + /* Cannot have any work since we either never got our IRQ registered, + * or never got interrupts enabled + */ + tasklet_kill(&adapter->work_task); + h_free_crq(vdev->unit_address); +reg_crq_failed: + dma_unmap_single(adapter->dev, + queue->msg_token, + queue->size * sizeof(*queue->msgs), DMA_BIDIRECTIONAL); +map_failed: + free_page((unsigned long)queue->msgs); +malloc_failed: + return -ENOMEM; +} + +/* Fill in the liobn and riobn fields on the adapter */ +static int read_dma_window(struct vio_dev *vdev, + struct crq_server_adapter *adapter) +{ + const __be32 *dma_window; + const __be32 *prop; + + /* TODO Using of_parse_dma_window would be better, but it doesn't give + * a way to read multiple windows without already knowing the size of + * a window or the number of windows + */ + dma_window = + (const __be32 *)vio_get_attribute(vdev, "ibm,my-dma-window", + NULL); + if (!dma_window) { + dev_warn(adapter->dev, "Couldn't find ibm,my-dma-window property\n"); + return -1; + } + + adapter->liobn = be32_to_cpu(*dma_window); + dma_window++; + + prop = (const __be32 *)vio_get_attribute(vdev, "ibm,#dma-address-cells", + NULL); + if (!prop) { + dev_warn(adapter->dev, "Couldn't find ibm,#dma-address-cells property\n"); + dma_window++; + } else { + dma_window += be32_to_cpu(*prop); + } + + prop = (const __be32 *)vio_get_attribute(vdev, "ibm,#dma-size-cells", + NULL); + if (!prop) { + dev_warn(adapter->dev, "Couldn't find ibm,#dma-size-cells property\n"); + dma_window++; + } else { + dma_window += be32_to_cpu(*prop); + } + + /* dma_window should point to the second window now */ + adapter->riobn = be32_to_cpu(*dma_window); + + return 0; +} + +static int ibmvmc_probe(struct vio_dev *vdev, const struct vio_device_id *id) +{ + struct crq_server_adapter *adapter = &ibmvmc_adapter; + int rc; + + dev_set_drvdata(&vdev->dev, NULL); + memset(adapter, 0, sizeof(*adapter)); + adapter->dev = &vdev->dev; + + dev_info(adapter->dev, "Probe for UA 0x%x\n", vdev->unit_address); + + rc = read_dma_window(vdev, adapter); + if (rc != 0) { + ibmvmc.state = ibmvmc_state_failed; + return -1; + } + + dev_dbg(adapter->dev, "Probe: liobn 0x%x, riobn 0x%x\n", + adapter->liobn, adapter->riobn); + + init_waitqueue_head(&adapter->reset_wait_queue); + adapter->reset_task = kthread_run(ibmvmc_reset_task, adapter, "ibmvmc"); + if (IS_ERR(adapter->reset_task)) { + dev_err(adapter->dev, "Failed to start reset thread\n"); + ibmvmc.state = ibmvmc_state_failed; + rc = PTR_ERR(adapter->reset_task); + adapter->reset_task = NULL; + return rc; + } + + rc = ibmvmc_init_crq_queue(adapter); + if (rc != 0 && rc != H_RESOURCE) { + dev_err(adapter->dev, "Error initializing CRQ. rc = 0x%x\n", + rc); + ibmvmc.state = ibmvmc_state_failed; + goto crq_failed; + } + + ibmvmc.state = ibmvmc_state_crqinit; + + /* Try to send an initialization message. Note that this is allowed + * to fail if the other end is not acive. In that case we just wait + * for the other side to initialize. + */ + if (ibmvmc_send_crq(adapter, 0xC001000000000000LL, 0) != 0 && + rc != H_RESOURCE) + dev_warn(adapter->dev, "Failed to send initialize CRQ message\n"); + + dev_set_drvdata(&vdev->dev, adapter); + + return 0; + +crq_failed: + kthread_stop(adapter->reset_task); + adapter->reset_task = NULL; + return -EPERM; +} + +static int ibmvmc_remove(struct vio_dev *vdev) +{ + struct crq_server_adapter *adapter = dev_get_drvdata(&vdev->dev); + + dev_info(adapter->dev, "Entering remove for UA 0x%x\n", + vdev->unit_address); + ibmvmc_release_crq_queue(adapter); + + return 0; +} + +static struct vio_device_id ibmvmc_device_table[] = { + { "ibm,vmc", "IBM,vmc" }, + { "", "" } +}; +MODULE_DEVICE_TABLE(vio, ibmvmc_device_table); + +static struct vio_driver ibmvmc_driver = { + .name = ibmvmc_driver_name, + .id_table = ibmvmc_device_table, + .probe = ibmvmc_probe, + .remove = ibmvmc_remove, +}; + +static void __init ibmvmc_scrub_module_parms(void) +{ + if (ibmvmc_max_mtu > MAX_MTU) { + pr_warn("ibmvmc: Max MTU reduced to %d\n", MAX_MTU); + ibmvmc_max_mtu = MAX_MTU; + } else if (ibmvmc_max_mtu < MIN_MTU) { + pr_warn("ibmvmc: Max MTU increased to %d\n", MIN_MTU); + ibmvmc_max_mtu = MIN_MTU; + } + + if (ibmvmc_max_buf_pool_size > MAX_BUF_POOL_SIZE) { + pr_warn("ibmvmc: Max buffer pool size reduced to %d\n", + MAX_BUF_POOL_SIZE); + ibmvmc_max_buf_pool_size = MAX_BUF_POOL_SIZE; + } else if (ibmvmc_max_buf_pool_size < MIN_BUF_POOL_SIZE) { + pr_warn("ibmvmc: Max buffer pool size increased to %d\n", + MIN_BUF_POOL_SIZE); + ibmvmc_max_buf_pool_size = MIN_BUF_POOL_SIZE; + } + + if (ibmvmc_max_hmcs > MAX_HMCS) { + pr_warn("ibmvmc: Max HMCs reduced to %d\n", MAX_HMCS); + ibmvmc_max_hmcs = MAX_HMCS; + } else if (ibmvmc_max_hmcs < MIN_HMCS) { + pr_warn("ibmvmc: Max HMCs increased to %d\n", MIN_HMCS); + ibmvmc_max_hmcs = MIN_HMCS; + } +} + +static struct miscdevice ibmvmc_miscdev = { + .name = ibmvmc_driver_name, + .minor = MISC_DYNAMIC_MINOR, + .fops = &ibmvmc_fops, +}; + +static int __init ibmvmc_module_init(void) +{ + int rc, i, j; + + ibmvmc.state = ibmvmc_state_initial; + pr_info("ibmvmc: version %s\n", IBMVMC_DRIVER_VERSION); + + rc = misc_register(&ibmvmc_miscdev); + if (rc) { + pr_err("ibmvmc: misc registration failed\n"); + goto misc_register_failed; + } + pr_info("ibmvmc: node %d:%d\n", MISC_MAJOR, + ibmvmc_miscdev.minor); + + /* Initialize data structures */ + memset(hmcs, 0, sizeof(struct ibmvmc_hmc) * MAX_HMCS); + for (i = 0; i < MAX_HMCS; i++) { + spin_lock_init(&hmcs[i].lock); + hmcs[i].state = ibmhmc_state_free; + for (j = 0; j < MAX_BUF_POOL_SIZE; j++) + hmcs[i].queue_outbound_msgs[j] = VMC_INVALID_BUFFER_ID; + } + + /* Sanity check module parms */ + ibmvmc_scrub_module_parms(); + + /* + * Initialize some reasonable values. Might be negotiated smaller + * values during the capabilities exchange. + */ + ibmvmc.max_mtu = ibmvmc_max_mtu; + ibmvmc.max_buffer_pool_size = ibmvmc_max_buf_pool_size; + ibmvmc.max_hmc_index = ibmvmc_max_hmcs - 1; + + rc = vio_register_driver(&ibmvmc_driver); + + if (rc) { + pr_err("ibmvmc: rc %d from vio_register_driver\n", rc); + goto vio_reg_failed; + } + + return 0; + +vio_reg_failed: + misc_deregister(&ibmvmc_miscdev); +misc_register_failed: + return rc; +} + +static void __exit ibmvmc_module_exit(void) +{ + pr_info("ibmvmc: module exit\n"); + vio_unregister_driver(&ibmvmc_driver); + misc_deregister(&ibmvmc_miscdev); +} + +module_init(ibmvmc_module_init); +module_exit(ibmvmc_module_exit); + +module_param_named(buf_pool_size, ibmvmc_max_buf_pool_size, + int, 0644); +MODULE_PARM_DESC(buf_pool_size, "Buffer pool size"); +module_param_named(max_hmcs, ibmvmc_max_hmcs, int, 0644); +MODULE_PARM_DESC(max_hmcs, "Max HMCs"); +module_param_named(max_mtu, ibmvmc_max_mtu, int, 0644); +MODULE_PARM_DESC(max_mtu, "Max MTU"); + +MODULE_AUTHOR("Steven Royer "); +MODULE_DESCRIPTION("IBM VMC"); +MODULE_VERSION(IBMVMC_DRIVER_VERSION); +MODULE_LICENSE("GPL v2"); diff --git a/drivers/misc/ibmvmc.h b/drivers/misc/ibmvmc.h new file mode 100644 index 000000000000..e140ada8fe2c --- /dev/null +++ b/drivers/misc/ibmvmc.h @@ -0,0 +1,209 @@ +/* SPDX-License-Identifier: GPL-2.0+ + * + * linux/drivers/misc/ibmvmc.h + * + * IBM Power Systems Virtual Management Channel Support. + * + * Copyright (c) 2004, 2018 IBM Corp. + * Dave Engebretsen engebret@us.ibm.com + * Steven Royer seroyer@linux.vnet.ibm.com + * Adam Reznechek adreznec@linux.vnet.ibm.com + * Bryant G. Ly + */ +#ifndef IBMVMC_H +#define IBMVMC_H + +#include +#include + +#include + +#define IBMVMC_PROTOCOL_VERSION 0x0101 + +#define MIN_BUF_POOL_SIZE 16 +#define MIN_HMCS 1 +#define MIN_MTU 4096 +#define MAX_BUF_POOL_SIZE 64 +#define MAX_HMCS 2 +#define MAX_MTU (4 * 4096) +#define DEFAULT_BUF_POOL_SIZE 32 +#define DEFAULT_HMCS 1 +#define DEFAULT_MTU 4096 +#define HMC_ID_LEN 32 + +#define VMC_INVALID_BUFFER_ID 0xFFFF + +/* ioctl numbers */ +#define VMC_BASE 0xCC +#define VMC_IOCTL_SETHMCID _IOW(VMC_BASE, 0x00, unsigned char *) +#define VMC_IOCTL_QUERY _IOR(VMC_BASE, 0x01, struct ibmvmc_query_struct) +#define VMC_IOCTL_REQUESTVMC _IOR(VMC_BASE, 0x02, u32) + +#define VMC_MSG_CAP 0x01 +#define VMC_MSG_CAP_RESP 0x81 +#define VMC_MSG_OPEN 0x02 +#define VMC_MSG_OPEN_RESP 0x82 +#define VMC_MSG_CLOSE 0x03 +#define VMC_MSG_CLOSE_RESP 0x83 +#define VMC_MSG_ADD_BUF 0x04 +#define VMC_MSG_ADD_BUF_RESP 0x84 +#define VMC_MSG_REM_BUF 0x05 +#define VMC_MSG_REM_BUF_RESP 0x85 +#define VMC_MSG_SIGNAL 0x06 + +#define VMC_MSG_SUCCESS 0 +#define VMC_MSG_INVALID_HMC_INDEX 1 +#define VMC_MSG_INVALID_BUFFER_ID 2 +#define VMC_MSG_CLOSED_HMC 3 +#define VMC_MSG_INTERFACE_FAILURE 4 +#define VMC_MSG_NO_BUFFER 5 + +#define VMC_BUF_OWNER_ALPHA 0 +#define VMC_BUF_OWNER_HV 1 + +enum ibmvmc_states { + ibmvmc_state_sched_reset = -1, + ibmvmc_state_initial = 0, + ibmvmc_state_crqinit = 1, + ibmvmc_state_capabilities = 2, + ibmvmc_state_ready = 3, + ibmvmc_state_failed = 4, +}; + +enum ibmhmc_states { + /* HMC connection not established */ + ibmhmc_state_free = 0, + + /* HMC connection established (open called) */ + ibmhmc_state_initial = 1, + + /* open msg sent to HV, due to ioctl(1) call */ + ibmhmc_state_opening = 2, + + /* HMC connection ready, open resp msg from HV */ + ibmhmc_state_ready = 3, + + /* HMC connection failure */ + ibmhmc_state_failed = 4, +}; + +struct ibmvmc_buffer { + u8 valid; /* 1 when DMA storage allocated to buffer */ + u8 free; /* 1 when buffer available for the Alpha Partition */ + u8 owner; + u16 id; + u32 size; + u32 msg_len; + dma_addr_t dma_addr_local; + dma_addr_t dma_addr_remote; + void *real_addr_local; +}; + +struct ibmvmc_admin_crq_msg { + u8 valid; /* RPA Defined */ + u8 type; /* ibmvmc msg type */ + u8 status; /* Response msg status. Zero is success and on failure, + * either 1 - General Failure, or 2 - Invalid Version is + * returned. + */ + u8 rsvd[2]; + u8 max_hmc; /* Max # of independent HMC connections supported */ + __be16 pool_size; /* Maximum number of buffers supported per HMC + * connection + */ + __be32 max_mtu; /* Maximum message size supported (bytes) */ + __be16 crq_size; /* # of entries available in the CRQ for the + * source partition. The target partition must + * limit the number of outstanding messages to + * one half or less. + */ + __be16 version; /* Indicates the code level of the management partition + * or the hypervisor with the high-order byte + * indicating a major version and the low-order byte + * indicating a minor version. + */ +}; + +struct ibmvmc_crq_msg { + u8 valid; /* RPA Defined */ + u8 type; /* ibmvmc msg type */ + u8 status; /* Response msg status */ + union { + u8 rsvd; /* Reserved */ + u8 owner; + } var1; + u8 hmc_session; /* Session Identifier for the current VMC connection */ + u8 hmc_index; /* A unique HMC Idx would be used if multiple management + * applications running concurrently were desired + */ + union { + __be16 rsvd; + __be16 buffer_id; + } var2; + __be32 rsvd; + union { + __be32 rsvd; + __be32 lioba; + __be32 msg_len; + } var3; +}; + +/* an RPA command/response transport queue */ +struct crq_queue { + struct ibmvmc_crq_msg *msgs; + int size, cur; + dma_addr_t msg_token; + spinlock_t lock; +}; + +/* VMC server adapter settings */ +struct crq_server_adapter { + struct device *dev; + struct crq_queue queue; + u32 liobn; + u32 riobn; + struct tasklet_struct work_task; + wait_queue_head_t reset_wait_queue; + struct task_struct *reset_task; +}; + +/* Driver wide settings */ +struct ibmvmc_struct { + u32 state; + u32 max_mtu; + u32 max_buffer_pool_size; + u32 max_hmc_index; + struct crq_server_adapter *adapter; + struct cdev cdev; + u32 vmc_drc_index; +}; + +struct ibmvmc_file_session; + +/* Connection specific settings */ +struct ibmvmc_hmc { + u8 session; + u8 index; + u32 state; + struct crq_server_adapter *adapter; + spinlock_t lock; + unsigned char hmc_id[HMC_ID_LEN]; + struct ibmvmc_buffer buffer[MAX_BUF_POOL_SIZE]; + unsigned short queue_outbound_msgs[MAX_BUF_POOL_SIZE]; + int queue_head, queue_tail; + struct ibmvmc_file_session *file_session; +}; + +struct ibmvmc_file_session { + struct file *file; + struct ibmvmc_hmc *hmc; + bool valid; +}; + +struct ibmvmc_query_struct { + int have_vmc; + int state; + int vmc_drc_index; +}; + +#endif /* __IBMVMC_H */