1 files changed, 629 insertions, 0 deletions

diff --git a/arch/ia64/kernel/salinfo.c b/arch/ia64/kernel/salinfo.c
new file mode 100644
index 000000000000..d227fabecd02
--- /dev/null
+++ b/arch/ia64/kernel/salinfo.c
@@ -0,0 +1,629 @@
+/*
+ * salinfo.c
+ *
+ * Creates entries in /proc/sal for various system features.
+ *
+ * Copyright (c) 2003 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.
+ */
+
+#include <linux/types.h>
+#include <linux/proc_fs.h>
+#include <linux/module.h>
+#include <linux/smp.h>
+#include <linux/smp_lock.h>
+#include <linux/timer.h>
+#include <linux/vmalloc.h>
+
+#include <asm/semaphore.h>
+#include <asm/sal.h>
+#include <asm/uaccess.h>
+
+MODULE_AUTHOR("Jesse Barnes <jbarnes@sgi.com>");
+MODULE_DESCRIPTION("/proc interface to IA-64 SAL features");
+MODULE_LICENSE("GPL");
+
+static int salinfo_read(char *page, char **start, off_t off, int count, int *eof, void *data);
+
+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 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 {
+        volatile cpumask_t      cpu_event;      /* which cpus have outstanding events */
+        struct semaphore        sem;            /* count of cpus with outstanding events (bits set in cpu_event) */
+        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 spinlock_t data_lock, 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 decded 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;
+        int ret;
+};
+
+static void
+salinfo_platform_oemdata_cpu(void *context)
+{
+        struct salinfo_platform_oemdata_parms *parms = context;
+        parms->ret = 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.
+ */
+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);
+        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;
+        }
+        if (irqsafe)
+                spin_unlock_irqrestore(&data_saved_lock, flags);
+
+        if (!test_and_set_bit(smp_processor_id(), &data->cpu_event)) {
+                if (irqsafe)
+                        up(&data->sem);
+        }
+}
+
+/* Check for outstanding MCA/INIT records every minute (arbitrary) */
+#define SALINFO_TIMER_DELAY (60*HZ)
+static struct timer_list salinfo_timer;
+
+static void
+salinfo_timeout_check(struct salinfo_data *data)
+{
+        int i;
+        if (!data->open)
+                return;
+        for (i = 0; i < NR_CPUS; ++i) {
+                if (test_bit(i, &data->cpu_event)) {
+                        /* double up() is not a problem, user space will see no
+                         * records for the additional "events".
+                         */
+                        up(&data->sem);
+                }
+        }
+}
+
+static void 
+salinfo_timeout (unsigned long arg)
+{
+        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 inode *inode = file->f_dentry->d_inode;
+        struct proc_dir_entry *entry = PDE(inode);
+        struct salinfo_data *data = entry->data;
+        char cmd[32];
+        size_t size;
+        int i, n, cpu = -1;
+
+retry:
+        if (down_trylock(&data->sem)) {
+                if (file->f_flags & O_NONBLOCK)
+                        return -EAGAIN;
+                if (down_interruptible(&data->sem))
+                        return -ERESTARTSYS;
+        }
+
+        n = data->cpu_check;
+        for (i = 0; i < NR_CPUS; i++) {
+                if (test_bit(n, &data->cpu_event)) {
+                        cpu = n;
+                        break;
+                }
+                if (++n == NR_CPUS)
+                        n = 0;
+        }
+
+        if (cpu == -1)
+                goto retry;
+
+        /* events are sticky until the user says "clear" */
+        up(&data->sem);
+
+        /* for next read, start checking at next CPU */
+        data->cpu_check = cpu;
+        if (++data->cpu_check == NR_CPUS)
+                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 struct file_operations salinfo_event_fops = {
+        .open  = salinfo_event_open,
+        .read  = salinfo_event_read,
+};
+
+static int
+salinfo_log_open(struct inode *inode, struct file *file)
+{
+        struct proc_dir_entry *entry = PDE(inode);
+        struct salinfo_data *data = entry->data;
+
+        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 proc_dir_entry *entry = PDE(inode);
+        struct salinfo_data *data = entry->data;
+
+        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 void
+call_on_cpu(int cpu, void (*fn)(void *), void *arg)
+{
+        cpumask_t save_cpus_allowed, new_cpus_allowed;
+        memcpy(&save_cpus_allowed, &current->cpus_allowed, sizeof(save_cpus_allowed));
+        memset(&new_cpus_allowed, 0, sizeof(new_cpus_allowed));
+        set_bit(cpu, &new_cpus_allowed);
+        set_cpus_allowed(current, new_cpus_allowed);
+        (*fn)(arg);
+        set_cpus_allowed(current, save_cpus_allowed);
+}
+
+static void
+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);
+}
+
+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)
+                call_on_cpu(cpu, salinfo_log_read_cpu, data);
+        if (!data->log_size) {
+                data->state = STATE_NO_DATA;
+                clear_bit(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 inode *inode = file->f_dentry->d_inode;
+        struct proc_dir_entry *entry = PDE(inode);
+        struct salinfo_data *data = entry->data;
+        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 void
+salinfo_log_clear_cpu(void *context)
+{
+        struct salinfo_data *data = context;
+        ia64_sal_clear_state_info(data->type);
+}
+
+static int
+salinfo_log_clear(struct salinfo_data *data, int cpu)
+{
+        sal_log_record_header_t *rh;
+        data->state = STATE_NO_DATA;
+        if (!test_bit(cpu, &data->cpu_event))
+                return 0;
+        down(&data->sem);
+        clear_bit(cpu, &data->cpu_event);
+        if (data->saved_num) {
+                unsigned long flags;
+                spin_lock_irqsave(&data_saved_lock, flags);
+                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)
+                call_on_cpu(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 &&
+            !test_and_set_bit(cpu,  &data->cpu_event))
+                up(&data->sem);
+        return 0;
+}
+
+static ssize_t
+salinfo_log_write(struct file *file, const char __user *buffer, size_t count, loff_t *ppos)
+{
+        struct inode *inode = file->f_dentry->d_inode;
+        struct proc_dir_entry *entry = PDE(inode);
+        struct salinfo_data *data = entry->data;
+        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
+                        };
+                        call_on_cpu(cpu, salinfo_platform_oemdata_cpu, &parms);
+                        if (parms.ret)
+                                count = parms.ret;
+                } else
+                        data->oemdata_size = 0;
+        } else
+                return -EINVAL;
+
+        return count;
+}
+
+static struct file_operations salinfo_data_fops = {
+        .open    = salinfo_log_open,
+        .release = salinfo_log_release,
+        .read    = salinfo_log_read,
+        .write   = salinfo_log_write,
+};
+
+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, j, online;
+
+        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++ = create_proc_read_entry (salinfo_entries[i].name, 0, salinfo_dir,
+                                                  salinfo_read, (void *)salinfo_entries[i].feature);
+        }
+
+        for (i = 0; i < ARRAY_SIZE(salinfo_log_name); i++) {
+                data = salinfo_data + i;
+                data->type = i;
+                sema_init(&data->sem, 0);
+                dir = proc_mkdir(salinfo_log_name[i], salinfo_dir);
+                if (!dir)
+                        continue;
+
+                entry = create_proc_entry("event", S_IRUSR, dir);
+                if (!entry)
+                        continue;
+                entry->data = data;
+                entry->proc_fops = &salinfo_event_fops;
+                *sdir++ = entry;
+
+                entry = create_proc_entry("data", S_IRUSR | S_IWUSR, dir);
+                if (!entry)
+                        continue;
+                entry->data = data;
+                entry->proc_fops = &salinfo_data_fops;
+                *sdir++ = entry;
+
+                /* we missed any events before now */
+                online = 0;
+                for (j = 0; j < NR_CPUS; j++)
+                        if (cpu_online(j)) {
+                                set_bit(j, &data->cpu_event);
+                                ++online;
+                        }
+                sema_init(&data->sem, online);
+
+                *sdir++ = dir;
+        }
+
+        *sdir++ = salinfo_dir;
+
+        init_timer(&salinfo_timer);
+        salinfo_timer.expires = jiffies + SALINFO_TIMER_DELAY;
+        salinfo_timer.function = &salinfo_timeout;
+        add_timer(&salinfo_timer);
+
+        return 0;
+}
+
+/*
+ * 'data' contains an integer that corresponds to the feature we're
+ * testing
+ */
+static int
+salinfo_read(char *page, char **start, off_t off, int count, int *eof, void *data)
+{
+        int len = 0;
+
+        len = sprintf(page, (sal_platform_features & (unsigned long)data) ? "1\n" : "0\n");
+
+        if (len <= off+count) *eof = 1;
+
+        *start = page + off;
+        len   -= off;
+
+        if (len>count) len = count;
+        if (len<0) len = 0;
+
+        return len;
+}
+
+module_init(salinfo_init);