EDAC, mce_amd_inj: Modify flags attribute to use string arguments

[cascardo/linux.git] / drivers / edac / mce_amd_inj.c

diff --git a/drivers/edac/mce_amd_inj.c b/drivers/edac/mce_amd_inj.c
index f7681b5..2a0c829 100644 (file)
--- a/drivers/edac/mce_amd_inj.c
+++ b/drivers/edac/mce_amd_inj.c
@@ -15,6 +15,8 @@
 #include <linux/device.h>
 #include <linux/module.h>
 #include <linux/cpu.h>
+#include <linux/string.h>
+#include <linux/uaccess.h>
 #include <asm/mce.h>
 
 #include "mce_amd.h"
@@ -25,6 +27,25 @@
 static struct mce i_mce;
 static struct dentry *dfs_inj;
 
+static u8 n_banks;
+
+#define MAX_FLAG_OPT_SIZE      3
+
+enum injection_type {
+       SW_INJ = 0,     /* SW injection, simply decode the error */
+       HW_INJ,         /* Trigger a #MC */
+       N_INJ_TYPES,
+};
+
+static const char * const flags_options[] = {
+       [SW_INJ] = "sw",
+       [HW_INJ] = "hw",
+       NULL
+};
+
+/* Set default injection to SW_INJ */
+enum injection_type inj_type = SW_INJ;
+
 #define MCE_INJECT_SET(reg)                                            \
 static int inj_##reg##_set(void *data, u64 val)                                \
 {                                                                      \
@@ -79,24 +100,66 @@ static int toggle_hw_mce_inject(unsigned int cpu, bool enable)
        return err;
 }
 
-static int flags_get(void *data, u64 *val)
+static int __set_inj(const char *buf)
 {
-       struct mce *m = (struct mce *)data;
+       int i;
 
-       *val = m->inject_flags;
+       for (i = 0; i < N_INJ_TYPES; i++) {
+               if (!strncmp(flags_options[i], buf, strlen(flags_options[i]))) {
+                       inj_type = i;
+                       return 0;
+               }
+       }
+       return -EINVAL;
+}
 
-       return 0;
+static ssize_t flags_read(struct file *filp, char __user *ubuf,
+                         size_t cnt, loff_t *ppos)
+{
+       char buf[MAX_FLAG_OPT_SIZE];
+       int n;
+
+       n = sprintf(buf, "%s\n", flags_options[inj_type]);
+
+       return simple_read_from_buffer(ubuf, cnt, ppos, buf, n);
 }
 
-static int flags_set(void *data, u64 val)
+static ssize_t flags_write(struct file *filp, const char __user *ubuf,
+                          size_t cnt, loff_t *ppos)
 {
-       struct mce *m = (struct mce *)data;
+       char buf[MAX_FLAG_OPT_SIZE], *__buf;
+       int err;
+       size_t ret;
 
-       m->inject_flags = (u8)val;
-       return 0;
+       if (cnt > MAX_FLAG_OPT_SIZE)
+               cnt = MAX_FLAG_OPT_SIZE;
+
+       ret = cnt;
+
+       if (copy_from_user(&buf, ubuf, cnt))
+               return -EFAULT;
+
+       buf[cnt - 1] = 0;
+
+       /* strip whitespace */
+       __buf = strstrip(buf);
+
+       err = __set_inj(__buf);
+       if (err) {
+               pr_err("%s: Invalid flags value: %s\n", __func__, __buf);
+               return err;
+       }
+
+       *ppos += ret;
+
+       return ret;
 }
 
-DEFINE_SIMPLE_ATTRIBUTE(flags_fops, flags_get, flags_set, "%llu\n");
+static const struct file_operations flags_fops = {
+       .read           = flags_read,
+       .write          = flags_write,
+       .llseek         = generic_file_llseek,
+};
 
 /*
  * On which CPU to inject?
@@ -128,7 +191,7 @@ static void do_inject(void)
        unsigned int cpu = i_mce.extcpu;
        u8 b = i_mce.bank;
 
-       if (!(i_mce.inject_flags & MCJ_EXCEPTION)) {
+       if (inj_type == SW_INJ) {
                amd_decode_mce(NULL, 0, &i_mce);
                return;
        }
@@ -174,11 +237,9 @@ static int inj_bank_set(void *data, u64 val)
 {
        struct mce *m = (struct mce *)data;
 
-       if (val > 5) {
-               if (boot_cpu_data.x86 != 0x15 || val > 6) {
-                       pr_err("Non-existent MCE bank: %llu\n", val);
-                       return -EINVAL;
-               }
+       if (val >= n_banks) {
+               pr_err("Non-existent MCE bank: %llu\n", val);
+               return -EINVAL;
        }
 
        m->bank = val;
@@ -187,13 +248,7 @@ static int inj_bank_set(void *data, u64 val)
        return 0;
 }
 
-static int inj_bank_get(void *data, u64 *val)
-{
-       struct mce *m = (struct mce *)data;
-
-       *val = m->bank;
-       return 0;
-}
+MCE_INJECT_GET(bank);
 
 DEFINE_SIMPLE_ATTRIBUTE(bank_fops, inj_bank_get, inj_bank_set, "%llu\n");
 
@@ -213,6 +268,10 @@ static struct dfs_node {
 static int __init init_mce_inject(void)
 {
        int i;
+       u64 cap;
+
+       rdmsrl(MSR_IA32_MCG_CAP, cap);
+       n_banks = cap & MCG_BANKCNT_MASK;
 
        dfs_inj = debugfs_create_dir("mce-inject", NULL);
        if (!dfs_inj)