diff options
Diffstat (limited to 'arch/powerpc/platforms/pseries/papr-hvpipe.c')
| -rw-r--r-- | arch/powerpc/platforms/pseries/papr-hvpipe.c | 818 |
1 files changed, 818 insertions, 0 deletions
diff --git a/arch/powerpc/platforms/pseries/papr-hvpipe.c b/arch/powerpc/platforms/pseries/papr-hvpipe.c new file mode 100644 index 000000000000..21a2f447c43f --- /dev/null +++ b/arch/powerpc/platforms/pseries/papr-hvpipe.c @@ -0,0 +1,818 @@ +// SPDX-License-Identifier: GPL-2.0-only + +#define pr_fmt(fmt) "papr-hvpipe: " fmt + +#include <linux/module.h> +#include <linux/kernel.h> +#include <linux/types.h> +#include <linux/delay.h> +#include <linux/anon_inodes.h> +#include <linux/miscdevice.h> +#include <linux/file.h> +#include <linux/fs.h> +#include <linux/poll.h> +#include <linux/of.h> +#include <asm/machdep.h> +#include <asm/rtas.h> +#include <asm/rtas-work-area.h> +#include <asm/papr-sysparm.h> +#include <uapi/asm/papr-hvpipe.h> +#include "pseries.h" +#include "papr-hvpipe.h" + +static DEFINE_SPINLOCK(hvpipe_src_list_lock); +static LIST_HEAD(hvpipe_src_list); + +static unsigned char hvpipe_ras_buf[RTAS_ERROR_LOG_MAX]; +static struct workqueue_struct *papr_hvpipe_wq; +static struct work_struct *papr_hvpipe_work; +static int hvpipe_check_exception_token; +static bool hvpipe_feature; + +/* + * New PowerPC FW provides support for partitions and various + * sources (Ex: remote hardware management console (HMC)) to + * exchange information through an inband hypervisor channel + * called HVPIPE. Only HMCs are supported right now and + * partitions can communicate with multiple HMCs and each + * source represented by source ID. + * + * FW introduces send HVPIPE and recv HVPIPE RTAS calls for + * partitions to send and receive payloads respectively. + * + * These RTAS functions have the following certain requirements + * / limitations: + * - One hvpipe per partition for all sources. + * - Assume the return status of send HVPIPE as delivered to source + * - Assume the return status of recv HVPIPE as ACK to source + * - Generates HVPIPE event message when the payload is ready + * for the partition. The hypervisor will not deliver another + * event until the partition read the previous payload which + * means the pipe is blocked for any sources. + * + * Linux implementation: + * Follow the similar interfaces that the OS has for other RTAS calls. + * ex: /dev/papr-indices, /dev/papr-vpd, etc. + * - /dev/papr-hvpipe is available for the user space. + * - devfd = open("/dev/papr-hvpipe", ..) + * - fd = ioctl(fd,HVPIPE_IOC_CREATE_HANDLE,&srcID)-for each source + * - write(fd, buf, size) --> Issue send HVPIPE RTAS call and + * returns size for success or the corresponding error for RTAS + * return code for failure. + * - poll(fd,..) -> wakeup FD if the payload is available to read. + * HVPIPE event message handler wakeup FD based on source ID in + * the event message + * - read(fd, buf, size) --> Issue recv HVPIPE RTAS call and + * returns size for success or the corresponding error for RTAS + * return code for failure. + */ + +/* + * ibm,receive-hvpipe-msg RTAS call. + * @area: Caller-provided work area buffer for results. + * @srcID: Source ID returned by the RTAS call. + * @bytesw: Bytes written by RTAS call to @area. + */ +static int rtas_ibm_receive_hvpipe_msg(struct rtas_work_area *area, + u32 *srcID, u32 *bytesw) +{ + const s32 token = rtas_function_token(RTAS_FN_IBM_RECEIVE_HVPIPE_MSG); + u32 rets[2]; + s32 fwrc; + int ret; + + if (token == RTAS_UNKNOWN_SERVICE) + return -ENOENT; + + do { + fwrc = rtas_call(token, 2, 3, rets, + rtas_work_area_phys(area), + rtas_work_area_size(area)); + + } while (rtas_busy_delay(fwrc)); + + switch (fwrc) { + case RTAS_SUCCESS: + *srcID = rets[0]; + *bytesw = rets[1]; + ret = 0; + break; + case RTAS_HARDWARE_ERROR: + ret = -EIO; + break; + case RTAS_INVALID_PARAMETER: + ret = -EINVAL; + break; + case RTAS_FUNC_NOT_SUPPORTED: + ret = -EOPNOTSUPP; + break; + default: + ret = -EIO; + pr_err_ratelimited("unexpected ibm,receive-hvpipe-msg status %d\n", fwrc); + break; + } + + return ret; +} + +/* + * ibm,send-hvpipe-msg RTAS call + * @area: Caller-provided work area buffer to send. + * @srcID: Target source for the send pipe message. + */ +static int rtas_ibm_send_hvpipe_msg(struct rtas_work_area *area, u32 srcID) +{ + const s32 token = rtas_function_token(RTAS_FN_IBM_SEND_HVPIPE_MSG); + s32 fwrc; + int ret; + + if (token == RTAS_UNKNOWN_SERVICE) + return -ENOENT; + + do { + fwrc = rtas_call(token, 2, 1, NULL, srcID, + rtas_work_area_phys(area)); + + } while (rtas_busy_delay(fwrc)); + + switch (fwrc) { + case RTAS_SUCCESS: + ret = 0; + break; + case RTAS_HARDWARE_ERROR: + ret = -EIO; + break; + case RTAS_INVALID_PARAMETER: + ret = -EINVAL; + break; + case RTAS_HVPIPE_CLOSED: + ret = -EPIPE; + break; + case RTAS_FUNC_NOT_SUPPORTED: + ret = -EOPNOTSUPP; + break; + default: + ret = -EIO; + pr_err_ratelimited("unexpected ibm,receive-hvpipe-msg status %d\n", fwrc); + break; + } + + return ret; +} + +static struct hvpipe_source_info *hvpipe_find_source(u32 srcID) +{ + struct hvpipe_source_info *src_info; + + list_for_each_entry(src_info, &hvpipe_src_list, list) + if (src_info->srcID == srcID) + return src_info; + + return NULL; +} + +/* + * This work function collects receive buffer with recv HVPIPE + * RTAS call. Called from read() + * @buf: User specified buffer to copy the payload that returned + * from recv HVPIPE RTAS. + * @size: Size of buffer user passed. + */ +static int hvpipe_rtas_recv_msg(char __user *buf, int size) +{ + struct rtas_work_area *work_area; + u32 srcID, bytes_written; + int ret; + + work_area = rtas_work_area_alloc(SZ_4K); + if (!work_area) { + pr_err("Could not allocate RTAS buffer for recv pipe\n"); + return -ENOMEM; + } + + ret = rtas_ibm_receive_hvpipe_msg(work_area, &srcID, + &bytes_written); + if (!ret) { + /* + * Recv HVPIPE RTAS is successful. + * When releasing FD or no one is waiting on the + * specific source, issue recv HVPIPE RTAS call + * so that pipe is not blocked - this func is called + * with NULL buf. + */ + if (buf) { + if (size < bytes_written) { + pr_err("Received the payload size = %d, but the buffer size = %d\n", + bytes_written, size); + bytes_written = size; + } + ret = copy_to_user(buf, + rtas_work_area_raw_buf(work_area), + bytes_written); + if (!ret) + ret = bytes_written; + } + } else { + pr_err("ibm,receive-hvpipe-msg failed with %d\n", + ret); + } + + rtas_work_area_free(work_area); + return ret; +} + +/* + * papr_hvpipe_handle_write - Issue send HVPIPE RTAS and return + * the size (payload + HVPIPE_HDR_LEN) for RTAS success. + * Otherwise returns the status of RTAS to the user space + */ +static ssize_t papr_hvpipe_handle_write(struct file *file, + const char __user *buf, size_t size, loff_t *off) +{ + struct hvpipe_source_info *src_info = file->private_data; + struct rtas_work_area *work_area, *work_buf; + unsigned long ret, len; + __be64 *area_be; + + /* + * Return -ENXIO during migration + */ + if (!hvpipe_feature) + return -ENXIO; + + if (!src_info) + return -EIO; + + /* + * Send HVPIPE RTAS is used to send payload to the specific + * source with the input parameters source ID and the payload + * as buffer list. Each entry in the buffer list contains + * address/length pair of the buffer. + * + * The buffer list format is as follows: + * + * Header (length of address/length pairs and the header length) + * Address of 4K buffer 1 + * Length of 4K buffer 1 used + * ... + * Address of 4K buffer n + * Length of 4K buffer n used + * + * See PAPR 7.3.32.2 ibm,send-hvpipe-msg + * + * Even though can support max 1MB payload, the hypervisor + * supports only 4048 bytes payload at present and also + * just one address/length entry. + * + * writev() interface can be added in future when the + * hypervisor supports multiple buffer list entries. + */ + /* HVPIPE_MAX_WRITE_BUFFER_SIZE = 4048 bytes */ + if ((size > (HVPIPE_HDR_LEN + HVPIPE_MAX_WRITE_BUFFER_SIZE)) || + (size <= HVPIPE_HDR_LEN)) + return -EINVAL; + + /* + * The length of (address + length) pair + the length of header + */ + len = (2 * sizeof(u64)) + sizeof(u64); + size -= HVPIPE_HDR_LEN; + buf += HVPIPE_HDR_LEN; + mutex_lock(&rtas_ibm_send_hvpipe_msg_lock); + work_area = rtas_work_area_alloc(SZ_4K); + if (!work_area) { + ret = -ENOMEM; + goto out; + } + area_be = (__be64 *)rtas_work_area_raw_buf(work_area); + /* header */ + area_be[0] = cpu_to_be64(len); + + work_buf = rtas_work_area_alloc(SZ_4K); + if (!work_buf) { + ret = -ENOMEM; + goto out_work; + } + /* First buffer address */ + area_be[1] = cpu_to_be64(rtas_work_area_phys(work_buf)); + /* First buffer address length */ + area_be[2] = cpu_to_be64(size); + + if (!copy_from_user(rtas_work_area_raw_buf(work_buf), buf, size)) { + ret = rtas_ibm_send_hvpipe_msg(work_area, src_info->srcID); + if (!ret) + ret = size + HVPIPE_HDR_LEN; + } else + ret = -EPERM; + + rtas_work_area_free(work_buf); +out_work: + rtas_work_area_free(work_area); +out: + mutex_unlock(&rtas_ibm_send_hvpipe_msg_lock); + return ret; +} + +/* + * papr_hvpipe_handle_read - If the payload for the specific + * source is pending in the hypervisor, issue recv HVPIPE RTAS + * and return the payload to the user space. + * + * When the payload is available for the partition, the + * hypervisor notifies HVPIPE event with the source ID + * and the event handler wakeup FD(s) that are waiting. + */ +static ssize_t papr_hvpipe_handle_read(struct file *file, + char __user *buf, size_t size, loff_t *off) +{ + + struct hvpipe_source_info *src_info = file->private_data; + struct papr_hvpipe_hdr hdr; + long ret; + + /* + * Return -ENXIO during migration + */ + if (!hvpipe_feature) + return -ENXIO; + + if (!src_info) + return -EIO; + + /* + * Max payload is 4048 (HVPIPE_MAX_WRITE_BUFFER_SIZE) + */ + if ((size > (HVPIPE_HDR_LEN + HVPIPE_MAX_WRITE_BUFFER_SIZE)) || + (size < HVPIPE_HDR_LEN)) + return -EINVAL; + + /* + * Payload is not available to receive or source pipe + * is not closed. + */ + if (!src_info->hvpipe_status) + return 0; + + hdr.version = 0; + hdr.flags = 0; + + /* + * In case if the hvpipe has payload and also the + * hypervisor closed the pipe to the source, retrieve + * the payload and return to the user space first and + * then notify the userspace about the hvpipe close in + * next read(). + */ + if (src_info->hvpipe_status & HVPIPE_MSG_AVAILABLE) + hdr.flags = HVPIPE_MSG_AVAILABLE; + else if (src_info->hvpipe_status & HVPIPE_LOST_CONNECTION) + hdr.flags = HVPIPE_LOST_CONNECTION; + else + /* + * Should not be here without one of the above + * flags set + */ + return -EIO; + + ret = copy_to_user(buf, &hdr, HVPIPE_HDR_LEN); + if (ret) + return ret; + + /* + * Message event has payload, so get the payload with + * recv HVPIPE RTAS. + */ + if (hdr.flags & HVPIPE_MSG_AVAILABLE) { + ret = hvpipe_rtas_recv_msg(buf + HVPIPE_HDR_LEN, + size - HVPIPE_HDR_LEN); + if (ret > 0) { + src_info->hvpipe_status &= ~HVPIPE_MSG_AVAILABLE; + ret += HVPIPE_HDR_LEN; + } + } else if (hdr.flags & HVPIPE_LOST_CONNECTION) { + /* + * Hypervisor is closing the pipe for the specific + * source. So notify user space. + */ + src_info->hvpipe_status &= ~HVPIPE_LOST_CONNECTION; + ret = HVPIPE_HDR_LEN; + } + + return ret; +} + +/* + * The user space waits for the payload to receive. + * The hypervisor sends HVPIPE event message to the partition + * when the payload is available. The event handler wakeup FD + * depends on the source ID in the message event. + */ +static __poll_t papr_hvpipe_handle_poll(struct file *filp, + struct poll_table_struct *wait) +{ + struct hvpipe_source_info *src_info = filp->private_data; + + /* + * HVPIPE is disabled during SUSPEND and enabled after migration. + * So return POLLRDHUP during migration + */ + if (!hvpipe_feature) + return POLLRDHUP; + + if (!src_info) + return POLLNVAL; + + /* + * If hvpipe already has pending payload, return so that + * the user space can issue read(). + */ + if (src_info->hvpipe_status) + return POLLIN | POLLRDNORM; + + /* + * Wait for the message event + * hvpipe_event_interrupt() wakes up this wait_queue + */ + poll_wait(filp, &src_info->recv_wqh, wait); + if (src_info->hvpipe_status) + return POLLIN | POLLRDNORM; + + return 0; +} + +static int papr_hvpipe_handle_release(struct inode *inode, + struct file *file) +{ + struct hvpipe_source_info *src_info; + + /* + * Hold the lock, remove source from src_list, reset the + * hvpipe status and release the lock to prevent any race + * with message event IRQ. + */ + spin_lock(&hvpipe_src_list_lock); + src_info = file->private_data; + list_del(&src_info->list); + file->private_data = NULL; + /* + * If the pipe for this specific source has any pending + * payload, issue recv HVPIPE RTAS so that pipe will not + * be blocked. + */ + if (src_info->hvpipe_status & HVPIPE_MSG_AVAILABLE) { + src_info->hvpipe_status = 0; + spin_unlock(&hvpipe_src_list_lock); + hvpipe_rtas_recv_msg(NULL, 0); + } else + spin_unlock(&hvpipe_src_list_lock); + + kfree(src_info); + return 0; +} + +static const struct file_operations papr_hvpipe_handle_ops = { + .read = papr_hvpipe_handle_read, + .write = papr_hvpipe_handle_write, + .release = papr_hvpipe_handle_release, + .poll = papr_hvpipe_handle_poll, +}; + +static int papr_hvpipe_dev_create_handle(u32 srcID) +{ + struct hvpipe_source_info *src_info; + struct file *file; + long err; + int fd; + + spin_lock(&hvpipe_src_list_lock); + /* + * Do not allow more than one process communicates with + * each source. + */ + src_info = hvpipe_find_source(srcID); + if (src_info) { + spin_unlock(&hvpipe_src_list_lock); + pr_err("pid(%d) is already using the source(%d)\n", + src_info->tsk->pid, srcID); + return -EALREADY; + } + spin_unlock(&hvpipe_src_list_lock); + + src_info = kzalloc(sizeof(*src_info), GFP_KERNEL_ACCOUNT); + if (!src_info) + return -ENOMEM; + + src_info->srcID = srcID; + src_info->tsk = current; + init_waitqueue_head(&src_info->recv_wqh); + + fd = get_unused_fd_flags(O_RDONLY | O_CLOEXEC); + if (fd < 0) { + err = fd; + goto free_buf; + } + + file = anon_inode_getfile("[papr-hvpipe]", + &papr_hvpipe_handle_ops, (void *)src_info, + O_RDWR); + if (IS_ERR(file)) { + err = PTR_ERR(file); + goto free_fd; + } + + spin_lock(&hvpipe_src_list_lock); + /* + * If two processes are executing ioctl() for the same + * source ID concurrently, prevent the second process to + * acquire FD. + */ + if (hvpipe_find_source(srcID)) { + spin_unlock(&hvpipe_src_list_lock); + err = -EALREADY; + goto free_file; + } + list_add(&src_info->list, &hvpipe_src_list); + spin_unlock(&hvpipe_src_list_lock); + + fd_install(fd, file); + return fd; + +free_file: + fput(file); +free_fd: + put_unused_fd(fd); +free_buf: + kfree(src_info); + return err; +} + +/* + * Top-level ioctl handler for /dev/papr_hvpipe + * + * Use separate FD for each source (exa :HMC). So ioctl is called + * with source ID which returns FD. + */ +static long papr_hvpipe_dev_ioctl(struct file *filp, unsigned int ioctl, + unsigned long arg) +{ + u32 __user *argp = (void __user *)arg; + u32 srcID; + long ret; + + /* + * Return -ENXIO during migration + */ + if (!hvpipe_feature) + return -ENXIO; + + if (get_user(srcID, argp)) + return -EFAULT; + + /* + * Support only HMC source right now + */ + if (!(srcID & HVPIPE_HMC_ID_MASK)) + return -EINVAL; + + switch (ioctl) { + case PAPR_HVPIPE_IOC_CREATE_HANDLE: + ret = papr_hvpipe_dev_create_handle(srcID); + break; + default: + ret = -ENOIOCTLCMD; + break; + } + + return ret; +} + +/* + * papr_hvpipe_work_fn - called to issue recv HVPIPE RTAS for + * sources that are not monitored by user space so that pipe + * will not be blocked. + */ +static void papr_hvpipe_work_fn(struct work_struct *work) +{ + hvpipe_rtas_recv_msg(NULL, 0); +} + +/* + * HVPIPE event message IRQ handler. + * The hypervisor sends event IRQ if the partition has payload + * and generates another event only after payload is read with + * recv HVPIPE RTAS. + */ +static irqreturn_t hvpipe_event_interrupt(int irq, void *dev_id) +{ + struct hvpipe_event_buf *hvpipe_event; + struct pseries_errorlog *pseries_log; + struct hvpipe_source_info *src_info; + struct rtas_error_log *elog; + int rc; + + rc = rtas_call(hvpipe_check_exception_token, 6, 1, NULL, + RTAS_VECTOR_EXTERNAL_INTERRUPT, virq_to_hw(irq), + RTAS_HVPIPE_MSG_EVENTS, 1, __pa(&hvpipe_ras_buf), + rtas_get_error_log_max()); + + if (rc != 0) { + pr_err_ratelimited("unexpected hvpipe-event-notification failed %d\n", rc); + return IRQ_HANDLED; + } + + elog = (struct rtas_error_log *)hvpipe_ras_buf; + if (unlikely(rtas_error_type(elog) != RTAS_TYPE_HVPIPE)) { + pr_warn_ratelimited("Unexpected event type %d\n", + rtas_error_type(elog)); + return IRQ_HANDLED; + } + + pseries_log = get_pseries_errorlog(elog, + PSERIES_ELOG_SECT_ID_HVPIPE_EVENT); + hvpipe_event = (struct hvpipe_event_buf *)pseries_log->data; + + /* + * The hypervisor notifies partition when the payload is + * available to read with recv HVPIPE RTAS and it will not + * notify another event for any source until the previous + * payload is read. Means the pipe is blocked in the + * hypervisor until the payload is read. + * + * If the source is ready to accept payload and wakeup the + * corresponding FD. Hold lock and update hvpipe_status + * and this lock is needed in case the user space process + * is in release FD instead of poll() so that release() + * reads the payload to unblock pipe before closing FD. + * + * otherwise (means no other user process waiting for the + * payload, issue recv HVPIPE RTAS (papr_hvpipe_work_fn()) + * to unblock pipe. + */ + spin_lock(&hvpipe_src_list_lock); + src_info = hvpipe_find_source(be32_to_cpu(hvpipe_event->srcID)); + if (src_info) { + u32 flags = 0; + + if (hvpipe_event->event_type & HVPIPE_LOST_CONNECTION) + flags = HVPIPE_LOST_CONNECTION; + else if (hvpipe_event->event_type & HVPIPE_MSG_AVAILABLE) + flags = HVPIPE_MSG_AVAILABLE; + + src_info->hvpipe_status |= flags; + wake_up(&src_info->recv_wqh); + spin_unlock(&hvpipe_src_list_lock); + } else { + spin_unlock(&hvpipe_src_list_lock); + /* + * user space is not waiting on this source. So + * execute receive pipe RTAS so that pipe will not + * be blocked. + */ + if (hvpipe_event->event_type & HVPIPE_MSG_AVAILABLE) + queue_work(papr_hvpipe_wq, papr_hvpipe_work); + } + + return IRQ_HANDLED; +} + +/* + * Enable hvpipe by system parameter set with parameter + * token = 64 and with 1 byte buffer data: + * 0 = hvpipe not in use/disable + * 1 = hvpipe in use/enable + */ +static int set_hvpipe_sys_param(u8 val) +{ + struct papr_sysparm_buf *buf; + int ret; + + buf = papr_sysparm_buf_alloc(); + if (!buf) + return -ENOMEM; + + buf->len = cpu_to_be16(1); + buf->val[0] = val; + ret = papr_sysparm_set(PAPR_SYSPARM_HVPIPE_ENABLE, buf); + if (ret) + pr_err("Can not enable hvpipe %d\n", ret); + + papr_sysparm_buf_free(buf); + + return ret; +} + +static int __init enable_hvpipe_IRQ(void) +{ + struct device_node *np; + + hvpipe_check_exception_token = rtas_function_token(RTAS_FN_CHECK_EXCEPTION); + if (hvpipe_check_exception_token == RTAS_UNKNOWN_SERVICE) + return -ENODEV; + + /* hvpipe events */ + np = of_find_node_by_path("/event-sources/ibm,hvpipe-msg-events"); + if (np != NULL) { + request_event_sources_irqs(np, hvpipe_event_interrupt, + "HPIPE_EVENT"); + of_node_put(np); + } else { + pr_err("Can not enable hvpipe event IRQ\n"); + return -ENODEV; + } + + return 0; +} + +void hvpipe_migration_handler(int action) +{ + pr_info("hvpipe migration event %d\n", action); + + /* + * HVPIPE is not used (Failed to create /dev/papr-hvpipe). + * So nothing to do for migration. + */ + if (!papr_hvpipe_work) + return; + + switch (action) { + case HVPIPE_SUSPEND: + if (hvpipe_feature) { + /* + * Disable hvpipe_feature to the user space. + * It will be enabled with RESUME event. + */ + hvpipe_feature = false; + /* + * set system parameter hvpipe 'disable' + */ + set_hvpipe_sys_param(0); + } + break; + case HVPIPE_RESUME: + /* + * set system parameter hvpipe 'enable' + */ + if (!set_hvpipe_sys_param(1)) + hvpipe_feature = true; + else + pr_err("hvpipe is not enabled after migration\n"); + + break; + } +} + +static const struct file_operations papr_hvpipe_ops = { + .unlocked_ioctl = papr_hvpipe_dev_ioctl, +}; + +static struct miscdevice papr_hvpipe_dev = { + .minor = MISC_DYNAMIC_MINOR, + .name = "papr-hvpipe", + .fops = &papr_hvpipe_ops, +}; + +static int __init papr_hvpipe_init(void) +{ + int ret; + + if (!of_find_property(rtas.dev, "ibm,hypervisor-pipe-capable", + NULL)) + return -ENODEV; + + if (!rtas_function_implemented(RTAS_FN_IBM_SEND_HVPIPE_MSG) || + !rtas_function_implemented(RTAS_FN_IBM_RECEIVE_HVPIPE_MSG)) + return -ENODEV; + + papr_hvpipe_work = kzalloc(sizeof(struct work_struct), GFP_ATOMIC); + if (!papr_hvpipe_work) + return -ENOMEM; + + INIT_WORK(papr_hvpipe_work, papr_hvpipe_work_fn); + + papr_hvpipe_wq = alloc_ordered_workqueue("papr hvpipe workqueue", 0); + if (!papr_hvpipe_wq) { + ret = -ENOMEM; + goto out; + } + + ret = enable_hvpipe_IRQ(); + if (!ret) { + ret = set_hvpipe_sys_param(1); + if (!ret) + ret = misc_register(&papr_hvpipe_dev); + } + + if (!ret) { + pr_info("hvpipe feature is enabled\n"); + hvpipe_feature = true; + return 0; + } + + pr_err("hvpipe feature is not enabled %d\n", ret); + destroy_workqueue(papr_hvpipe_wq); +out: + kfree(papr_hvpipe_work); + papr_hvpipe_work = NULL; + return ret; +} +machine_device_initcall(pseries, papr_hvpipe_init); |