ASR_BASE
Change-Id: Icf3719cc0afe3eeb3edc7fa80a2eb5199ca9dda1
diff --git a/marvell/linux/arch/x86/kernel/cpu/mce/dev-mcelog.c b/marvell/linux/arch/x86/kernel/cpu/mce/dev-mcelog.c
new file mode 100644
index 0000000..7c8958d
--- /dev/null
+++ b/marvell/linux/arch/x86/kernel/cpu/mce/dev-mcelog.c
@@ -0,0 +1,359 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * /dev/mcelog driver
+ *
+ * K8 parts Copyright 2002,2003 Andi Kleen, SuSE Labs.
+ * Rest from unknown author(s).
+ * 2004 Andi Kleen. Rewrote most of it.
+ * Copyright 2008 Intel Corporation
+ * Author: Andi Kleen
+ */
+
+#include <linux/miscdevice.h>
+#include <linux/slab.h>
+#include <linux/kmod.h>
+#include <linux/poll.h>
+
+#include "internal.h"
+
+static BLOCKING_NOTIFIER_HEAD(mce_injector_chain);
+
+static DEFINE_MUTEX(mce_chrdev_read_mutex);
+
+static char mce_helper[128];
+static char *mce_helper_argv[2] = { mce_helper, NULL };
+
+/*
+ * Lockless MCE logging infrastructure.
+ * This avoids deadlocks on printk locks without having to break locks. Also
+ * separate MCEs from kernel messages to avoid bogus bug reports.
+ */
+
+static struct mce_log_buffer mcelog = {
+ .signature = MCE_LOG_SIGNATURE,
+ .len = MCE_LOG_LEN,
+ .recordlen = sizeof(struct mce),
+};
+
+static DECLARE_WAIT_QUEUE_HEAD(mce_chrdev_wait);
+
+static int dev_mce_log(struct notifier_block *nb, unsigned long val,
+ void *data)
+{
+ struct mce *mce = (struct mce *)data;
+ unsigned int entry;
+
+ mutex_lock(&mce_chrdev_read_mutex);
+
+ entry = mcelog.next;
+
+ /*
+ * When the buffer fills up discard new entries. Assume that the
+ * earlier errors are the more interesting ones:
+ */
+ if (entry >= MCE_LOG_LEN) {
+ set_bit(MCE_OVERFLOW, (unsigned long *)&mcelog.flags);
+ goto unlock;
+ }
+
+ mcelog.next = entry + 1;
+
+ memcpy(mcelog.entry + entry, mce, sizeof(struct mce));
+ mcelog.entry[entry].finished = 1;
+
+ /* wake processes polling /dev/mcelog */
+ wake_up_interruptible(&mce_chrdev_wait);
+
+unlock:
+ mutex_unlock(&mce_chrdev_read_mutex);
+
+ return NOTIFY_OK;
+}
+
+static struct notifier_block dev_mcelog_nb = {
+ .notifier_call = dev_mce_log,
+ .priority = MCE_PRIO_MCELOG,
+};
+
+static void mce_do_trigger(struct work_struct *work)
+{
+ call_usermodehelper(mce_helper, mce_helper_argv, NULL, UMH_NO_WAIT);
+}
+
+static DECLARE_WORK(mce_trigger_work, mce_do_trigger);
+
+
+void mce_work_trigger(void)
+{
+ if (mce_helper[0])
+ schedule_work(&mce_trigger_work);
+}
+
+static ssize_t
+show_trigger(struct device *s, struct device_attribute *attr, char *buf)
+{
+ strcpy(buf, mce_helper);
+ strcat(buf, "\n");
+ return strlen(mce_helper) + 1;
+}
+
+static ssize_t set_trigger(struct device *s, struct device_attribute *attr,
+ const char *buf, size_t siz)
+{
+ char *p;
+
+ strncpy(mce_helper, buf, sizeof(mce_helper));
+ mce_helper[sizeof(mce_helper)-1] = 0;
+ p = strchr(mce_helper, '\n');
+
+ if (p)
+ *p = 0;
+
+ return strlen(mce_helper) + !!p;
+}
+
+DEVICE_ATTR(trigger, 0644, show_trigger, set_trigger);
+
+/*
+ * mce_chrdev: Character device /dev/mcelog to read and clear the MCE log.
+ */
+
+static DEFINE_SPINLOCK(mce_chrdev_state_lock);
+static int mce_chrdev_open_count; /* #times opened */
+static int mce_chrdev_open_exclu; /* already open exclusive? */
+
+static int mce_chrdev_open(struct inode *inode, struct file *file)
+{
+ spin_lock(&mce_chrdev_state_lock);
+
+ if (mce_chrdev_open_exclu ||
+ (mce_chrdev_open_count && (file->f_flags & O_EXCL))) {
+ spin_unlock(&mce_chrdev_state_lock);
+
+ return -EBUSY;
+ }
+
+ if (file->f_flags & O_EXCL)
+ mce_chrdev_open_exclu = 1;
+ mce_chrdev_open_count++;
+
+ spin_unlock(&mce_chrdev_state_lock);
+
+ return nonseekable_open(inode, file);
+}
+
+static int mce_chrdev_release(struct inode *inode, struct file *file)
+{
+ spin_lock(&mce_chrdev_state_lock);
+
+ mce_chrdev_open_count--;
+ mce_chrdev_open_exclu = 0;
+
+ spin_unlock(&mce_chrdev_state_lock);
+
+ return 0;
+}
+
+static int mce_apei_read_done;
+
+/* Collect MCE record of previous boot in persistent storage via APEI ERST. */
+static int __mce_read_apei(char __user **ubuf, size_t usize)
+{
+ int rc;
+ u64 record_id;
+ struct mce m;
+
+ if (usize < sizeof(struct mce))
+ return -EINVAL;
+
+ rc = apei_read_mce(&m, &record_id);
+ /* Error or no more MCE record */
+ if (rc <= 0) {
+ mce_apei_read_done = 1;
+ /*
+ * When ERST is disabled, mce_chrdev_read() should return
+ * "no record" instead of "no device."
+ */
+ if (rc == -ENODEV)
+ return 0;
+ return rc;
+ }
+ rc = -EFAULT;
+ if (copy_to_user(*ubuf, &m, sizeof(struct mce)))
+ return rc;
+ /*
+ * In fact, we should have cleared the record after that has
+ * been flushed to the disk or sent to network in
+ * /sbin/mcelog, but we have no interface to support that now,
+ * so just clear it to avoid duplication.
+ */
+ rc = apei_clear_mce(record_id);
+ if (rc) {
+ mce_apei_read_done = 1;
+ return rc;
+ }
+ *ubuf += sizeof(struct mce);
+
+ return 0;
+}
+
+static ssize_t mce_chrdev_read(struct file *filp, char __user *ubuf,
+ size_t usize, loff_t *off)
+{
+ char __user *buf = ubuf;
+ unsigned next;
+ int i, err;
+
+ mutex_lock(&mce_chrdev_read_mutex);
+
+ if (!mce_apei_read_done) {
+ err = __mce_read_apei(&buf, usize);
+ if (err || buf != ubuf)
+ goto out;
+ }
+
+ /* Only supports full reads right now */
+ err = -EINVAL;
+ if (*off != 0 || usize < MCE_LOG_LEN*sizeof(struct mce))
+ goto out;
+
+ next = mcelog.next;
+ err = 0;
+
+ for (i = 0; i < next; i++) {
+ struct mce *m = &mcelog.entry[i];
+
+ err |= copy_to_user(buf, m, sizeof(*m));
+ buf += sizeof(*m);
+ }
+
+ memset(mcelog.entry, 0, next * sizeof(struct mce));
+ mcelog.next = 0;
+
+ if (err)
+ err = -EFAULT;
+
+out:
+ mutex_unlock(&mce_chrdev_read_mutex);
+
+ return err ? err : buf - ubuf;
+}
+
+static __poll_t mce_chrdev_poll(struct file *file, poll_table *wait)
+{
+ poll_wait(file, &mce_chrdev_wait, wait);
+ if (READ_ONCE(mcelog.next))
+ return EPOLLIN | EPOLLRDNORM;
+ if (!mce_apei_read_done && apei_check_mce())
+ return EPOLLIN | EPOLLRDNORM;
+ return 0;
+}
+
+static long mce_chrdev_ioctl(struct file *f, unsigned int cmd,
+ unsigned long arg)
+{
+ int __user *p = (int __user *)arg;
+
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+
+ switch (cmd) {
+ case MCE_GET_RECORD_LEN:
+ return put_user(sizeof(struct mce), p);
+ case MCE_GET_LOG_LEN:
+ return put_user(MCE_LOG_LEN, p);
+ case MCE_GETCLEAR_FLAGS: {
+ unsigned flags;
+
+ do {
+ flags = mcelog.flags;
+ } while (cmpxchg(&mcelog.flags, flags, 0) != flags);
+
+ return put_user(flags, p);
+ }
+ default:
+ return -ENOTTY;
+ }
+}
+
+void mce_register_injector_chain(struct notifier_block *nb)
+{
+ blocking_notifier_chain_register(&mce_injector_chain, nb);
+}
+EXPORT_SYMBOL_GPL(mce_register_injector_chain);
+
+void mce_unregister_injector_chain(struct notifier_block *nb)
+{
+ blocking_notifier_chain_unregister(&mce_injector_chain, nb);
+}
+EXPORT_SYMBOL_GPL(mce_unregister_injector_chain);
+
+static ssize_t mce_chrdev_write(struct file *filp, const char __user *ubuf,
+ size_t usize, loff_t *off)
+{
+ struct mce m;
+
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+ /*
+ * There are some cases where real MSR reads could slip
+ * through.
+ */
+ if (!boot_cpu_has(X86_FEATURE_MCE) || !boot_cpu_has(X86_FEATURE_MCA))
+ return -EIO;
+
+ if ((unsigned long)usize > sizeof(struct mce))
+ usize = sizeof(struct mce);
+ if (copy_from_user(&m, ubuf, usize))
+ return -EFAULT;
+
+ if (m.extcpu >= num_possible_cpus() || !cpu_online(m.extcpu))
+ return -EINVAL;
+
+ /*
+ * Need to give user space some time to set everything up,
+ * so do it a jiffie or two later everywhere.
+ */
+ schedule_timeout(2);
+
+ blocking_notifier_call_chain(&mce_injector_chain, 0, &m);
+
+ return usize;
+}
+
+static const struct file_operations mce_chrdev_ops = {
+ .open = mce_chrdev_open,
+ .release = mce_chrdev_release,
+ .read = mce_chrdev_read,
+ .write = mce_chrdev_write,
+ .poll = mce_chrdev_poll,
+ .unlocked_ioctl = mce_chrdev_ioctl,
+ .llseek = no_llseek,
+};
+
+static struct miscdevice mce_chrdev_device = {
+ MISC_MCELOG_MINOR,
+ "mcelog",
+ &mce_chrdev_ops,
+};
+
+static __init int dev_mcelog_init_device(void)
+{
+ int err;
+
+ /* register character device /dev/mcelog */
+ err = misc_register(&mce_chrdev_device);
+ if (err) {
+ if (err == -EBUSY)
+ /* Xen dom0 might have registered the device already. */
+ pr_info("Unable to init device /dev/mcelog, already registered");
+ else
+ pr_err("Unable to init device /dev/mcelog (rc: %d)\n", err);
+
+ return err;
+ }
+
+ mce_register_decode_chain(&dev_mcelog_nb);
+ return 0;
+}
+device_initcall_sync(dev_mcelog_init_device);