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-rw-r--r--arch/ia64/kernel/salinfo.c646
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diff --git a/arch/ia64/kernel/salinfo.c b/arch/ia64/kernel/salinfo.c
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+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * salinfo.c
+ *
+ * Creates entries in /proc/sal for various system features.
+ *
+ * Copyright (c) 2003, 2006 Silicon Graphics, Inc. All rights reserved.
+ * Copyright (c) 2003 Hewlett-Packard Co
+ * Bjorn Helgaas <bjorn.helgaas@hp.com>
+ *
+ * 10/30/2001 jbarnes@sgi.com copied much of Stephane's palinfo
+ * code to create this file
+ * Oct 23 2003 kaos@sgi.com
+ * Replace IPI with set_cpus_allowed() to read a record from the required cpu.
+ * Redesign salinfo log processing to separate interrupt and user space
+ * contexts.
+ * Cache the record across multi-block reads from user space.
+ * Support > 64 cpus.
+ * Delete module_exit and MOD_INC/DEC_COUNT, salinfo cannot be a module.
+ *
+ * Jan 28 2004 kaos@sgi.com
+ * Periodically check for outstanding MCA or INIT records.
+ *
+ * Dec 5 2004 kaos@sgi.com
+ * Standardize which records are cleared automatically.
+ *
+ * Aug 18 2005 kaos@sgi.com
+ * mca.c may not pass a buffer, a NULL buffer just indicates that a new
+ * record is available in SAL.
+ * Replace some NR_CPUS by cpus_online, for hotplug cpu.
+ *
+ * Jan 5 2006 kaos@sgi.com
+ * Handle hotplug cpus coming online.
+ * Handle hotplug cpus going offline while they still have outstanding records.
+ * Use the cpu_* macros consistently.
+ * Replace the counting semaphore with a mutex and a test if the cpumask is non-empty.
+ * Modify the locking to make the test for "work to do" an atomic operation.
+ */
+
+#include <linux/capability.h>
+#include <linux/cpu.h>
+#include <linux/types.h>
+#include <linux/proc_fs.h>
+#include <linux/seq_file.h>
+#include <linux/module.h>
+#include <linux/smp.h>
+#include <linux/timer.h>
+#include <linux/vmalloc.h>
+#include <linux/semaphore.h>
+
+#include <asm/sal.h>
+#include <linux/uaccess.h>
+
+MODULE_AUTHOR("Jesse Barnes <jbarnes@sgi.com>");
+MODULE_DESCRIPTION("/proc interface to IA-64 SAL features");
+MODULE_LICENSE("GPL");
+
+typedef struct {
+ const char *name; /* name of the proc entry */
+ unsigned long feature; /* feature bit */
+ struct proc_dir_entry *entry; /* registered entry (removal) */
+} salinfo_entry_t;
+
+/*
+ * List {name,feature} pairs for every entry in /proc/sal/<feature>
+ * that this module exports
+ */
+static const salinfo_entry_t salinfo_entries[]={
+ { "bus_lock", IA64_SAL_PLATFORM_FEATURE_BUS_LOCK, },
+ { "irq_redirection", IA64_SAL_PLATFORM_FEATURE_IRQ_REDIR_HINT, },
+ { "ipi_redirection", IA64_SAL_PLATFORM_FEATURE_IPI_REDIR_HINT, },
+ { "itc_drift", IA64_SAL_PLATFORM_FEATURE_ITC_DRIFT, },
+};
+
+#define NR_SALINFO_ENTRIES ARRAY_SIZE(salinfo_entries)
+
+static char *salinfo_log_name[] = {
+ "mca",
+ "init",
+ "cmc",
+ "cpe",
+};
+
+static struct proc_dir_entry *salinfo_proc_entries[
+ ARRAY_SIZE(salinfo_entries) + /* /proc/sal/bus_lock */
+ ARRAY_SIZE(salinfo_log_name) + /* /proc/sal/{mca,...} */
+ (2 * ARRAY_SIZE(salinfo_log_name)) + /* /proc/sal/mca/{event,data} */
+ 1]; /* /proc/sal */
+
+/* Some records we get ourselves, some are accessed as saved data in buffers
+ * that are owned by mca.c.
+ */
+struct salinfo_data_saved {
+ u8* buffer;
+ u64 size;
+ u64 id;
+ int cpu;
+};
+
+/* State transitions. Actions are :-
+ * Write "read <cpunum>" to the data file.
+ * Write "clear <cpunum>" to the data file.
+ * Write "oemdata <cpunum> <offset> to the data file.
+ * Read from the data file.
+ * Close the data file.
+ *
+ * Start state is NO_DATA.
+ *
+ * NO_DATA
+ * write "read <cpunum>" -> NO_DATA or LOG_RECORD.
+ * write "clear <cpunum>" -> NO_DATA or LOG_RECORD.
+ * write "oemdata <cpunum> <offset> -> return -EINVAL.
+ * read data -> return EOF.
+ * close -> unchanged. Free record areas.
+ *
+ * LOG_RECORD
+ * write "read <cpunum>" -> NO_DATA or LOG_RECORD.
+ * write "clear <cpunum>" -> NO_DATA or LOG_RECORD.
+ * write "oemdata <cpunum> <offset> -> format the oem data, goto OEMDATA.
+ * read data -> return the INIT/MCA/CMC/CPE record.
+ * close -> unchanged. Keep record areas.
+ *
+ * OEMDATA
+ * write "read <cpunum>" -> NO_DATA or LOG_RECORD.
+ * write "clear <cpunum>" -> NO_DATA or LOG_RECORD.
+ * write "oemdata <cpunum> <offset> -> format the oem data, goto OEMDATA.
+ * read data -> return the formatted oemdata.
+ * close -> unchanged. Keep record areas.
+ *
+ * Closing the data file does not change the state. This allows shell scripts
+ * to manipulate salinfo data, each shell redirection opens the file, does one
+ * action then closes it again. The record areas are only freed at close when
+ * the state is NO_DATA.
+ */
+enum salinfo_state {
+ STATE_NO_DATA,
+ STATE_LOG_RECORD,
+ STATE_OEMDATA,
+};
+
+struct salinfo_data {
+ cpumask_t cpu_event; /* which cpus have outstanding events */
+ wait_queue_head_t read_wait;
+ u8 *log_buffer;
+ u64 log_size;
+ u8 *oemdata; /* decoded oem data */
+ u64 oemdata_size;
+ int open; /* single-open to prevent races */
+ u8 type;
+ u8 saved_num; /* using a saved record? */
+ enum salinfo_state state :8; /* processing state */
+ u8 padding;
+ int cpu_check; /* next CPU to check */
+ struct salinfo_data_saved data_saved[5];/* save last 5 records from mca.c, must be < 255 */
+};
+
+static struct salinfo_data salinfo_data[ARRAY_SIZE(salinfo_log_name)];
+
+static DEFINE_SPINLOCK(data_lock);
+static DEFINE_SPINLOCK(data_saved_lock);
+
+/** salinfo_platform_oemdata - optional callback to decode oemdata from an error
+ * record.
+ * @sect_header: pointer to the start of the section to decode.
+ * @oemdata: returns vmalloc area containing the decoded output.
+ * @oemdata_size: returns length of decoded output (strlen).
+ *
+ * Description: If user space asks for oem data to be decoded by the kernel
+ * and/or prom and the platform has set salinfo_platform_oemdata to the address
+ * of a platform specific routine then call that routine. salinfo_platform_oemdata
+ * vmalloc's and formats its output area, returning the address of the text
+ * and its strlen. Returns 0 for success, -ve for error. The callback is
+ * invoked on the cpu that generated the error record.
+ */
+int (*salinfo_platform_oemdata)(const u8 *sect_header, u8 **oemdata, u64 *oemdata_size);
+
+struct salinfo_platform_oemdata_parms {
+ const u8 *efi_guid;
+ u8 **oemdata;
+ u64 *oemdata_size;
+};
+
+static long
+salinfo_platform_oemdata_cpu(void *context)
+{
+ struct salinfo_platform_oemdata_parms *parms = context;
+
+ return salinfo_platform_oemdata(parms->efi_guid, parms->oemdata, parms->oemdata_size);
+}
+
+static void
+shift1_data_saved (struct salinfo_data *data, int shift)
+{
+ memcpy(data->data_saved+shift, data->data_saved+shift+1,
+ (ARRAY_SIZE(data->data_saved) - (shift+1)) * sizeof(data->data_saved[0]));
+ memset(data->data_saved + ARRAY_SIZE(data->data_saved) - 1, 0,
+ sizeof(data->data_saved[0]));
+}
+
+/* This routine is invoked in interrupt context. Note: mca.c enables
+ * interrupts before calling this code for CMC/CPE. MCA and INIT events are
+ * not irq safe, do not call any routines that use spinlocks, they may deadlock.
+ * MCA and INIT records are recorded, a timer event will look for any
+ * outstanding events and wake up the user space code.
+ *
+ * The buffer passed from mca.c points to the output from ia64_log_get. This is
+ * a persistent buffer but its contents can change between the interrupt and
+ * when user space processes the record. Save the record id to identify
+ * changes. If the buffer is NULL then just update the bitmap.
+ */
+void
+salinfo_log_wakeup(int type, u8 *buffer, u64 size, int irqsafe)
+{
+ struct salinfo_data *data = salinfo_data + type;
+ struct salinfo_data_saved *data_saved;
+ unsigned long flags = 0;
+ int i;
+ int saved_size = ARRAY_SIZE(data->data_saved);
+
+ BUG_ON(type >= ARRAY_SIZE(salinfo_log_name));
+
+ if (irqsafe)
+ spin_lock_irqsave(&data_saved_lock, flags);
+ if (buffer) {
+ for (i = 0, data_saved = data->data_saved; i < saved_size; ++i, ++data_saved) {
+ if (!data_saved->buffer)
+ break;
+ }
+ if (i == saved_size) {
+ if (!data->saved_num) {
+ shift1_data_saved(data, 0);
+ data_saved = data->data_saved + saved_size - 1;
+ } else
+ data_saved = NULL;
+ }
+ if (data_saved) {
+ data_saved->cpu = smp_processor_id();
+ data_saved->id = ((sal_log_record_header_t *)buffer)->id;
+ data_saved->size = size;
+ data_saved->buffer = buffer;
+ }
+ }
+ cpumask_set_cpu(smp_processor_id(), &data->cpu_event);
+ if (irqsafe) {
+ wake_up_interruptible(&data->read_wait);
+ spin_unlock_irqrestore(&data_saved_lock, flags);
+ }
+}
+
+/* Check for outstanding MCA/INIT records every minute (arbitrary) */
+#define SALINFO_TIMER_DELAY (60*HZ)
+static struct timer_list salinfo_timer;
+extern void ia64_mlogbuf_dump(void);
+
+static void
+salinfo_timeout_check(struct salinfo_data *data)
+{
+ if (!data->open)
+ return;
+ if (!cpumask_empty(&data->cpu_event))
+ wake_up_interruptible(&data->read_wait);
+}
+
+static void
+salinfo_timeout(struct timer_list *unused)
+{
+ ia64_mlogbuf_dump();
+ salinfo_timeout_check(salinfo_data + SAL_INFO_TYPE_MCA);
+ salinfo_timeout_check(salinfo_data + SAL_INFO_TYPE_INIT);
+ salinfo_timer.expires = jiffies + SALINFO_TIMER_DELAY;
+ add_timer(&salinfo_timer);
+}
+
+static int
+salinfo_event_open(struct inode *inode, struct file *file)
+{
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+ return 0;
+}
+
+static ssize_t
+salinfo_event_read(struct file *file, char __user *buffer, size_t count, loff_t *ppos)
+{
+ struct salinfo_data *data = PDE_DATA(file_inode(file));
+ char cmd[32];
+ size_t size;
+ int i, n, cpu = -1;
+
+retry:
+ if (cpumask_empty(&data->cpu_event)) {
+ if (file->f_flags & O_NONBLOCK)
+ return -EAGAIN;
+ if (wait_event_interruptible(data->read_wait,
+ !cpumask_empty(&data->cpu_event)))
+ return -EINTR;
+ }
+
+ n = data->cpu_check;
+ for (i = 0; i < nr_cpu_ids; i++) {
+ if (cpumask_test_cpu(n, &data->cpu_event)) {
+ if (!cpu_online(n)) {
+ cpumask_clear_cpu(n, &data->cpu_event);
+ continue;
+ }
+ cpu = n;
+ break;
+ }
+ if (++n == nr_cpu_ids)
+ n = 0;
+ }
+
+ if (cpu == -1)
+ goto retry;
+
+ ia64_mlogbuf_dump();
+
+ /* for next read, start checking at next CPU */
+ data->cpu_check = cpu;
+ if (++data->cpu_check == nr_cpu_ids)
+ data->cpu_check = 0;
+
+ snprintf(cmd, sizeof(cmd), "read %d\n", cpu);
+
+ size = strlen(cmd);
+ if (size > count)
+ size = count;
+ if (copy_to_user(buffer, cmd, size))
+ return -EFAULT;
+
+ return size;
+}
+
+static const struct proc_ops salinfo_event_proc_ops = {
+ .proc_open = salinfo_event_open,
+ .proc_read = salinfo_event_read,
+ .proc_lseek = noop_llseek,
+};
+
+static int
+salinfo_log_open(struct inode *inode, struct file *file)
+{
+ struct salinfo_data *data = PDE_DATA(inode);
+
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+
+ spin_lock(&data_lock);
+ if (data->open) {
+ spin_unlock(&data_lock);
+ return -EBUSY;
+ }
+ data->open = 1;
+ spin_unlock(&data_lock);
+
+ if (data->state == STATE_NO_DATA &&
+ !(data->log_buffer = vmalloc(ia64_sal_get_state_info_size(data->type)))) {
+ data->open = 0;
+ return -ENOMEM;
+ }
+
+ return 0;
+}
+
+static int
+salinfo_log_release(struct inode *inode, struct file *file)
+{
+ struct salinfo_data *data = PDE_DATA(inode);
+
+ if (data->state == STATE_NO_DATA) {
+ vfree(data->log_buffer);
+ vfree(data->oemdata);
+ data->log_buffer = NULL;
+ data->oemdata = NULL;
+ }
+ spin_lock(&data_lock);
+ data->open = 0;
+ spin_unlock(&data_lock);
+ return 0;
+}
+
+static long
+salinfo_log_read_cpu(void *context)
+{
+ struct salinfo_data *data = context;
+ sal_log_record_header_t *rh;
+ data->log_size = ia64_sal_get_state_info(data->type, (u64 *) data->log_buffer);
+ rh = (sal_log_record_header_t *)(data->log_buffer);
+ /* Clear corrected errors as they are read from SAL */
+ if (rh->severity == sal_log_severity_corrected)
+ ia64_sal_clear_state_info(data->type);
+ return 0;
+}
+
+static void
+salinfo_log_new_read(int cpu, struct salinfo_data *data)
+{
+ struct salinfo_data_saved *data_saved;
+ unsigned long flags;
+ int i;
+ int saved_size = ARRAY_SIZE(data->data_saved);
+
+ data->saved_num = 0;
+ spin_lock_irqsave(&data_saved_lock, flags);
+retry:
+ for (i = 0, data_saved = data->data_saved; i < saved_size; ++i, ++data_saved) {
+ if (data_saved->buffer && data_saved->cpu == cpu) {
+ sal_log_record_header_t *rh = (sal_log_record_header_t *)(data_saved->buffer);
+ data->log_size = data_saved->size;
+ memcpy(data->log_buffer, rh, data->log_size);
+ barrier(); /* id check must not be moved */
+ if (rh->id == data_saved->id) {
+ data->saved_num = i+1;
+ break;
+ }
+ /* saved record changed by mca.c since interrupt, discard it */
+ shift1_data_saved(data, i);
+ goto retry;
+ }
+ }
+ spin_unlock_irqrestore(&data_saved_lock, flags);
+
+ if (!data->saved_num)
+ work_on_cpu_safe(cpu, salinfo_log_read_cpu, data);
+ if (!data->log_size) {
+ data->state = STATE_NO_DATA;
+ cpumask_clear_cpu(cpu, &data->cpu_event);
+ } else {
+ data->state = STATE_LOG_RECORD;
+ }
+}
+
+static ssize_t
+salinfo_log_read(struct file *file, char __user *buffer, size_t count, loff_t *ppos)
+{
+ struct salinfo_data *data = PDE_DATA(file_inode(file));
+ u8 *buf;
+ u64 bufsize;
+
+ if (data->state == STATE_LOG_RECORD) {
+ buf = data->log_buffer;
+ bufsize = data->log_size;
+ } else if (data->state == STATE_OEMDATA) {
+ buf = data->oemdata;
+ bufsize = data->oemdata_size;
+ } else {
+ buf = NULL;
+ bufsize = 0;
+ }
+ return simple_read_from_buffer(buffer, count, ppos, buf, bufsize);
+}
+
+static long
+salinfo_log_clear_cpu(void *context)
+{
+ struct salinfo_data *data = context;
+
+ ia64_sal_clear_state_info(data->type);
+ return 0;
+}
+
+static int
+salinfo_log_clear(struct salinfo_data *data, int cpu)
+{
+ sal_log_record_header_t *rh;
+ unsigned long flags;
+ spin_lock_irqsave(&data_saved_lock, flags);
+ data->state = STATE_NO_DATA;
+ if (!cpumask_test_cpu(cpu, &data->cpu_event)) {
+ spin_unlock_irqrestore(&data_saved_lock, flags);
+ return 0;
+ }
+ cpumask_clear_cpu(cpu, &data->cpu_event);
+ if (data->saved_num) {
+ shift1_data_saved(data, data->saved_num - 1);
+ data->saved_num = 0;
+ }
+ spin_unlock_irqrestore(&data_saved_lock, flags);
+ rh = (sal_log_record_header_t *)(data->log_buffer);
+ /* Corrected errors have already been cleared from SAL */
+ if (rh->severity != sal_log_severity_corrected)
+ work_on_cpu_safe(cpu, salinfo_log_clear_cpu, data);
+ /* clearing a record may make a new record visible */
+ salinfo_log_new_read(cpu, data);
+ if (data->state == STATE_LOG_RECORD) {
+ spin_lock_irqsave(&data_saved_lock, flags);
+ cpumask_set_cpu(cpu, &data->cpu_event);
+ wake_up_interruptible(&data->read_wait);
+ spin_unlock_irqrestore(&data_saved_lock, flags);
+ }
+ return 0;
+}
+
+static ssize_t
+salinfo_log_write(struct file *file, const char __user *buffer, size_t count, loff_t *ppos)
+{
+ struct salinfo_data *data = PDE_DATA(file_inode(file));
+ char cmd[32];
+ size_t size;
+ u32 offset;
+ int cpu;
+
+ size = sizeof(cmd);
+ if (count < size)
+ size = count;
+ if (copy_from_user(cmd, buffer, size))
+ return -EFAULT;
+
+ if (sscanf(cmd, "read %d", &cpu) == 1) {
+ salinfo_log_new_read(cpu, data);
+ } else if (sscanf(cmd, "clear %d", &cpu) == 1) {
+ int ret;
+ if ((ret = salinfo_log_clear(data, cpu)))
+ count = ret;
+ } else if (sscanf(cmd, "oemdata %d %d", &cpu, &offset) == 2) {
+ if (data->state != STATE_LOG_RECORD && data->state != STATE_OEMDATA)
+ return -EINVAL;
+ if (offset > data->log_size - sizeof(efi_guid_t))
+ return -EINVAL;
+ data->state = STATE_OEMDATA;
+ if (salinfo_platform_oemdata) {
+ struct salinfo_platform_oemdata_parms parms = {
+ .efi_guid = data->log_buffer + offset,
+ .oemdata = &data->oemdata,
+ .oemdata_size = &data->oemdata_size
+ };
+ count = work_on_cpu_safe(cpu, salinfo_platform_oemdata_cpu,
+ &parms);
+ } else
+ data->oemdata_size = 0;
+ } else
+ return -EINVAL;
+
+ return count;
+}
+
+static const struct proc_ops salinfo_data_proc_ops = {
+ .proc_open = salinfo_log_open,
+ .proc_release = salinfo_log_release,
+ .proc_read = salinfo_log_read,
+ .proc_write = salinfo_log_write,
+ .proc_lseek = default_llseek,
+};
+
+static int salinfo_cpu_online(unsigned int cpu)
+{
+ unsigned int i, end = ARRAY_SIZE(salinfo_data);
+ struct salinfo_data *data;
+
+ spin_lock_irq(&data_saved_lock);
+ for (i = 0, data = salinfo_data; i < end; ++i, ++data) {
+ cpumask_set_cpu(cpu, &data->cpu_event);
+ wake_up_interruptible(&data->read_wait);
+ }
+ spin_unlock_irq(&data_saved_lock);
+ return 0;
+}
+
+static int salinfo_cpu_pre_down(unsigned int cpu)
+{
+ unsigned int i, end = ARRAY_SIZE(salinfo_data);
+ struct salinfo_data *data;
+
+ spin_lock_irq(&data_saved_lock);
+ for (i = 0, data = salinfo_data; i < end; ++i, ++data) {
+ struct salinfo_data_saved *data_saved;
+ int j = ARRAY_SIZE(data->data_saved) - 1;
+
+ for (data_saved = data->data_saved + j; j >= 0;
+ --j, --data_saved) {
+ if (data_saved->buffer && data_saved->cpu == cpu)
+ shift1_data_saved(data, j);
+ }
+ cpumask_clear_cpu(cpu, &data->cpu_event);
+ }
+ spin_unlock_irq(&data_saved_lock);
+ return 0;
+}
+
+/*
+ * 'data' contains an integer that corresponds to the feature we're
+ * testing
+ */
+static int __maybe_unused proc_salinfo_show(struct seq_file *m, void *v)
+{
+ unsigned long data = (unsigned long)v;
+ seq_puts(m, (sal_platform_features & data) ? "1\n" : "0\n");
+ return 0;
+}
+
+static int __init
+salinfo_init(void)
+{
+ struct proc_dir_entry *salinfo_dir; /* /proc/sal dir entry */
+ struct proc_dir_entry **sdir = salinfo_proc_entries; /* keeps track of every entry */
+ struct proc_dir_entry *dir, *entry;
+ struct salinfo_data *data;
+ int i;
+
+ salinfo_dir = proc_mkdir("sal", NULL);
+ if (!salinfo_dir)
+ return 0;
+
+ for (i=0; i < NR_SALINFO_ENTRIES; i++) {
+ /* pass the feature bit in question as misc data */
+ *sdir++ = proc_create_single_data(salinfo_entries[i].name, 0,
+ salinfo_dir, proc_salinfo_show,
+ (void *)salinfo_entries[i].feature);
+ }
+
+ for (i = 0; i < ARRAY_SIZE(salinfo_log_name); i++) {
+ data = salinfo_data + i;
+ data->type = i;
+ init_waitqueue_head(&data->read_wait);
+ dir = proc_mkdir(salinfo_log_name[i], salinfo_dir);
+ if (!dir)
+ continue;
+
+ entry = proc_create_data("event", S_IRUSR, dir,
+ &salinfo_event_proc_ops, data);
+ if (!entry)
+ continue;
+ *sdir++ = entry;
+
+ entry = proc_create_data("data", S_IRUSR | S_IWUSR, dir,
+ &salinfo_data_proc_ops, data);
+ if (!entry)
+ continue;
+ *sdir++ = entry;
+
+ *sdir++ = dir;
+ }
+
+ *sdir++ = salinfo_dir;
+
+ timer_setup(&salinfo_timer, salinfo_timeout, 0);
+ salinfo_timer.expires = jiffies + SALINFO_TIMER_DELAY;
+ add_timer(&salinfo_timer);
+
+ i = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "ia64/salinfo:online",
+ salinfo_cpu_online, salinfo_cpu_pre_down);
+ WARN_ON(i < 0);
+ return 0;
+}
+
+module_init(salinfo_init);
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-28 18:25:04 +0000