On Tue, Mar 31, 2020 at 1:59 AM Alastair D'Silva <alast...@d-silva.org> wrote:
>
> The read error log command extracts information from the controller's
> internal error log.
>
> This patch exposes this information in 2 ways:
> - During probe, if an error occurs & a log is available, print it to the
> console
> - After probe, make the error log available to userspace via an IOCTL.
> Userspace is notified of pending error logs in a later patch
> ("powerpc/powernv/pmem: Forward events to userspace")
So, have a look at the recent papr_scm patches to add health flags and
smart data retrieval. I'd prefer to extend existing nvdimm device
retrieval mechanisms than invent new ones.
>
> Signed-off-by: Alastair D'Silva <alast...@d-silva.org>
> ---
> .../userspace-api/ioctl/ioctl-number.rst | 1 +
> drivers/nvdimm/ocxl/main.c | 240 ++++++++++++++++++
> include/uapi/nvdimm/ocxlpmem.h | 46 ++++
> 3 files changed, 287 insertions(+)
> create mode 100644 include/uapi/nvdimm/ocxlpmem.h
>
> diff --git a/Documentation/userspace-api/ioctl/ioctl-number.rst
> b/Documentation/userspace-api/ioctl/ioctl-number.rst
> index 9425377615ce..ba0ce7dca643 100644
> --- a/Documentation/userspace-api/ioctl/ioctl-number.rst
> +++ b/Documentation/userspace-api/ioctl/ioctl-number.rst
> @@ -340,6 +340,7 @@ Code Seq# Include File
> Comments
> 0xC0 00-0F linux/usb/iowarrior.h
> 0xCA 00-0F uapi/misc/cxl.h
> 0xCA 10-2F uapi/misc/ocxl.h
> +0xCA 30-3F uapi/nvdimm/ocxlpmem.h
> OpenCAPI Persistent Memory
> 0xCA 80-BF uapi/scsi/cxlflash_ioctl.h
> 0xCB 00-1F CBM
> serial IEC bus in development:
>
> <mailto:michael.kl...@puffin.lb.shuttle.de>
> diff --git a/drivers/nvdimm/ocxl/main.c b/drivers/nvdimm/ocxl/main.c
> index 9b85fcd3f1c9..e6be0029f658 100644
> --- a/drivers/nvdimm/ocxl/main.c
> +++ b/drivers/nvdimm/ocxl/main.c
> @@ -13,6 +13,7 @@
> #include <linux/fs.h>
> #include <linux/mm_types.h>
> #include <linux/memory_hotplug.h>
> +#include <uapi/nvdimm/ocxlpmem.h>
> #include "ocxlpmem.h"
>
> static const struct pci_device_id pci_tbl[] = {
> @@ -401,10 +402,190 @@ static int file_release(struct inode *inode, struct
> file *file)
> return 0;
> }
>
> +/**
> + * error_log_header_parse() - Parse the first 64 bits of the error log
> command response
> + * @ocxlpmem: the device metadata
> + * @length: out, returns the number of bytes in the response (excluding the
> 64 bit header)
> + */
> +static int error_log_header_parse(struct ocxlpmem *ocxlpmem, u16 *length)
> +{
> + int rc;
> + u64 val;
> + u16 data_identifier;
> + u32 data_length;
> +
> + rc = ocxl_global_mmio_read64(ocxlpmem->ocxl_afu,
> + ocxlpmem->admin_command.data_offset,
> + OCXL_LITTLE_ENDIAN, &val);
> + if (rc)
> + return rc;
> +
> + data_identifier = val >> 48;
> + data_length = val & 0xFFFF;
> +
> + if (data_identifier != 0x454C) { // 'EL'
> + dev_err(&ocxlpmem->dev,
> + "Bad data identifier for error log data, expected
> 'EL', got '%2s' (%#x), data_length=%u\n",
> + (char *)&data_identifier,
> + (unsigned int)data_identifier, data_length);
> + return -EINVAL;
> + }
> +
> + *length = data_length;
> + return 0;
> +}
> +
> +static int read_error_log(struct ocxlpmem *ocxlpmem,
> + struct ioctl_ocxlpmem_error_log *log,
> + bool buf_is_user)
> +{
> + u64 val;
> + u16 user_buf_length;
> + u16 buf_length;
> + u64 *buf = (u64 *)log->buf_ptr;
> + u16 i;
> + int rc;
> +
> + if (log->buf_size % 8)
> + return -EINVAL;
> +
> + rc = ocxlpmem_chi(ocxlpmem, &val);
> + if (rc)
> + return rc;
> +
> + if (!(val & GLOBAL_MMIO_CHI_ELA))
> + return -EAGAIN;
> +
> + user_buf_length = log->buf_size;
> +
> + mutex_lock(&ocxlpmem->admin_command.lock);
> +
> + rc = admin_command_execute(ocxlpmem, ADMIN_COMMAND_ERRLOG);
> + if (rc != STATUS_SUCCESS) {
> + warn_status(ocxlpmem,
> + "Unexpected status from retrieve error log", rc);
> + goto out;
> + }
> +
> + rc = error_log_header_parse(ocxlpmem, &log->buf_size);
> + if (rc)
> + goto out;
> + // log->buf_size now contains the returned buffer size, not the user
> size
> +
> + rc = ocxl_global_mmio_read64(ocxlpmem->ocxl_afu,
> + ocxlpmem->admin_command.data_offset +
> 0x08,
> + OCXL_LITTLE_ENDIAN, &val);
> + if (rc)
> + goto out;
> +
> + log->log_identifier = val >> 32;
> + log->program_reference_code = val & 0xFFFFFFFF;
> +
> + rc = ocxl_global_mmio_read64(ocxlpmem->ocxl_afu,
> + ocxlpmem->admin_command.data_offset +
> 0x10,
> + OCXL_LITTLE_ENDIAN, &val);
> + if (rc)
> + goto out;
> +
> + log->error_log_type = val >> 56;
> + log->action_flags = (log->error_log_type ==
> OCXLPMEM_ERROR_LOG_TYPE_GENERAL) ?
> + (val >> 32) & 0xFFFFFF : 0;
> + log->power_on_seconds = val & 0xFFFFFFFF;
> +
> + rc = ocxl_global_mmio_read64(ocxlpmem->ocxl_afu,
> + ocxlpmem->admin_command.data_offset +
> 0x18,
> + OCXL_LITTLE_ENDIAN, &log->timestamp);
> + if (rc)
> + goto out;
> +
> + rc = ocxl_global_mmio_read64(ocxlpmem->ocxl_afu,
> + ocxlpmem->admin_command.data_offset +
> 0x20,
> + OCXL_LITTLE_ENDIAN, &log->wwid[0]);
> + if (rc)
> + goto out;
> +
> + rc = ocxl_global_mmio_read64(ocxlpmem->ocxl_afu,
> + ocxlpmem->admin_command.data_offset +
> 0x28,
> + OCXL_LITTLE_ENDIAN, &log->wwid[1]);
> + if (rc)
> + goto out;
> +
> + rc = ocxl_global_mmio_read64(ocxlpmem->ocxl_afu,
> + ocxlpmem->admin_command.data_offset +
> 0x30,
> + OCXL_HOST_ENDIAN, (u64
> *)log->fw_revision);
> + if (rc)
> + goto out;
> + log->fw_revision[8] = '\0';
> +
> + buf_length = (user_buf_length < log->buf_size) ?
> + user_buf_length : log->buf_size;
> + for (i = 0; i < buf_length / (sizeof(u64)); i++) {
> + rc = ocxl_global_mmio_read64(ocxlpmem->ocxl_afu,
> +
> ocxlpmem->admin_command.data_offset +
> + i * sizeof(u64),
> + OCXL_HOST_ENDIAN, &val);
> + if (rc)
> + goto out;
> +
> + if (buf_is_user) {
> + if (copy_to_user((u64 __user *)&buf[i], &val,
> + sizeof(u64))) {
> + rc = -EFAULT;
> + goto out;
> + }
> + } else {
> + buf[i] = val;
> + }
> + }
> +
> + rc = admin_response_handled(ocxlpmem);
> + if (rc)
> + goto out;
> +
> +out:
> + mutex_unlock(&ocxlpmem->admin_command.lock);
> + return rc;
> +}
> +
> +static int ioctl_error_log(struct ocxlpmem *ocxlpmem,
> + struct ioctl_ocxlpmem_error_log __user *uarg)
> +{
> + struct ioctl_ocxlpmem_error_log args;
> + int rc;
> +
> + if (copy_from_user(&args, uarg, sizeof(args)))
> + return -EFAULT;
> +
> + rc = read_error_log(ocxlpmem, &args, true);
> + if (rc)
> + return rc;
> +
> + if (copy_to_user(uarg, &args, sizeof(args)))
> + return -EFAULT;
> +
> + return 0;
> +}
> +
> +static long file_ioctl(struct file *file, unsigned int cmd, unsigned long
> args)
> +{
> + struct ocxlpmem *ocxlpmem = file->private_data;
> + int rc = -EINVAL;
> +
> + switch (cmd) {
> + case IOCTL_OCXLPMEM_ERROR_LOG:
> + rc = ioctl_error_log(ocxlpmem,
> + (struct ioctl_ocxlpmem_error_log __user
> *)args);
> + break;
> + }
> + return rc;
> +}
> +
> static const struct file_operations fops = {
> .owner = THIS_MODULE,
> .open = file_open,
> .release = file_release,
> + .unlocked_ioctl = file_ioctl,
> + .compat_ioctl = file_ioctl,
> };
>
> /**
> @@ -493,6 +674,60 @@ static int read_device_metadata(struct ocxlpmem
> *ocxlpmem)
> return 0;
> }
>
> +static const char *decode_error_log_type(u8 error_log_type)
> +{
> + switch (error_log_type) {
> + case 0x00:
> + return "general";
> + case 0x01:
> + return "predictive failure";
> + case 0x02:
> + return "thermal warning";
> + case 0x03:
> + return "data loss";
> + case 0x04:
> + return "health & performance";
> + default:
> + return "unknown";
> + }
> +}
> +
> +static void dump_error_log(struct ocxlpmem *ocxlpmem)
> +{
> + struct ioctl_ocxlpmem_error_log log;
> + u32 buf_size;
> + u8 *buf;
> + int rc;
> +
> + if (ocxlpmem->admin_command.data_size == 0)
> + return;
> +
> + buf_size = ocxlpmem->admin_command.data_size - 0x48;
> + buf = kzalloc(buf_size, GFP_KERNEL);
> + if (!buf)
> + return;
> +
> + log.buf_ptr = (u64)buf;
> + log.buf_size = buf_size;
> +
> + rc = read_error_log(ocxlpmem, &log, false);
> + if (rc < 0)
> + goto out;
> +
> + dev_warn(&ocxlpmem->dev,
> + "OCXL PMEM Error log: WWID=0x%016llx%016llx LID=0x%x PRC=%x
> type=0x%x %s, Uptime=%u seconds timestamp=0x%llx\n",
> + log.wwid[0], log.wwid[1],
> + log.log_identifier, log.program_reference_code,
> + log.error_log_type,
> + decode_error_log_type(log.error_log_type),
> + log.power_on_seconds, log.timestamp);
> + print_hex_dump(KERN_WARNING, "buf", DUMP_PREFIX_OFFSET, 16, 1, buf,
> + log.buf_size, false);
> +
> +out:
> + kfree(buf);
> +}
> +
> /**
> * probe_function0() - Set up function 0 for an OpenCAPI persistent memory
> device
> * This is important as it enables templates higher than 0 across all other
> @@ -656,6 +891,11 @@ static int probe(struct pci_dev *pdev, const struct
> pci_device_id *ent)
> pci_set_drvdata(pdev, NULL);
>
> err:
> + if (ocxlpmem &&
> + (ocxlpmem_chi(ocxlpmem, &chi) == 0) &&
> + (chi & GLOBAL_MMIO_CHI_ELA))
> + dump_error_log(ocxlpmem);
> +
> /*
> * Further cleanup is done in the release handler via free_ocxlpmem()
> * This allows us to keep the character device live to handle IOCTLs
> to
> diff --git a/include/uapi/nvdimm/ocxlpmem.h b/include/uapi/nvdimm/ocxlpmem.h
> new file mode 100644
> index 000000000000..5d3a03ea1e08
> --- /dev/null
> +++ b/include/uapi/nvdimm/ocxlpmem.h
> @@ -0,0 +1,46 @@
> +/* SPDX-License-Identifier: GPL-2.0+ WITH Linux-syscall-note */
> +/* Copyright 2020 IBM Corp. */
> +#ifndef _UAPI_OCXL_SCM_H
> +#define _UAPI_OCXL_SCM_H
> +
> +#include <linux/types.h>
> +#include <linux/ioctl.h>
> +
> +#define OCXLPMEM_ERROR_LOG_ACTION_RESET (1 << (32 - 32))
> +#define OCXLPMEM_ERROR_LOG_ACTION_CHKFW (1 << (53 - 32))
> +#define OCXLPMEM_ERROR_LOG_ACTION_REPLACE (1 << (54 - 32))
> +#define OCXLPMEM_ERROR_LOG_ACTION_DUMP (1 << (55 - 32))
> +
> +#define OCXLPMEM_ERROR_LOG_TYPE_GENERAL (0x00)
> +#define OCXLPMEM_ERROR_LOG_TYPE_PREDICTIVE_FAILURE (0x01)
> +#define OCXLPMEM_ERROR_LOG_TYPE_THERMAL_WARNING (0x02)
> +#define OCXLPMEM_ERROR_LOG_TYPE_DATA_LOSS (0x03)
> +#define OCXLPMEM_ERROR_LOG_TYPE_HEALTH_PERFORMANCE (0x04)
> +
> +struct ioctl_ocxlpmem_error_log {
> + __u32 log_identifier; /* out */
> + __u32 program_reference_code; /* out */
> + __u32 action_flags; /* out, recommended course of action */
> + __u32 power_on_seconds; /* out, Number of seconds the controller has
> been on when the error occurred */
> + __u64 timestamp; /* out, relative time since the current IPL */
> + __u64 wwid[2]; /* out, the NAA formatted WWID associated with the
> controller */
> + char fw_revision[8 + 1]; /* out, firmware revision as null
> terminated text */
> + __u8 reserved0[7];
> + __u16 buf_size; /* in/out, buffer size provided/required.
> + * If required is greater than provided, the buffer
> + * will be truncated to the amount provided. If its
> + * less, then only the required bytes will be
> populated.
> + * If it is 0, then there are no more error log
> entries.
> + */
> + __u8 error_log_type;
> + __u8 reserved1[5];
> + __u64 buf_ptr; /* coerced pointer to output buffer */
> + __u64 reserved2[2];
> +};
> +
> +/* ioctl numbers */
> +#define OCXLPMEM_MAGIC 0xCA
> +/* OpenCAPI Persistent memory devices */
> +#define IOCTL_OCXLPMEM_ERROR_LOG _IOWR(OCXLPMEM_MAGIC,
> 0x30, struct ioctl_ocxlpmem_error_log)
> +
> +#endif /* _UAPI_OCXL_SCM_H */
> --
> 2.24.1
>
