efi-pstore: Refactor erase routine

[sfrench/cifs-2.6.git] / drivers / firmware / efi / efi-pstore.c

diff --git a/drivers/firmware/efi/efi-pstore.c b/drivers/firmware/efi/efi-pstore.c
index ef1fafdad4008ae7fa1824396592e0e53cf61002..d30dc935e20ede22808e26e08a58917be5aee490 100644 (file)
--- a/drivers/firmware/efi/efi-pstore.c
+++ b/drivers/firmware/efi/efi-pstore.c
@@ -4,7 +4,7 @@
 #include <linux/slab.h>
 #include <linux/ucs2_string.h>
 
-#define DUMP_NAME_LEN 52
+#define DUMP_NAME_LEN 66
 
 static bool efivars_pstore_disable =
        IS_ENABLED(CONFIG_EFI_VARS_PSTORE_DEFAULT_DISABLE);
@@ -250,6 +250,9 @@ static int efi_pstore_write(struct pstore_record *record)
        record->id = generic_id(record->time.tv_sec, record->part,
                                record->count);
 
+       /* Since we copy the entire length of name, make sure it is wiped. */
+       memset(name, 0, sizeof(name));
+
        snprintf(name, sizeof(name), "dump-type%u-%u-%d-%lu-%c",
                 record->type, record->part, record->count,
                 record->time.tv_sec, record->compressed ? 'C' : 'D');
@@ -267,44 +270,20 @@ static int efi_pstore_write(struct pstore_record *record)
        return ret;
 };
 
-struct pstore_erase_data {
-       struct pstore_record *record;
-       efi_char16_t *name;
-};
-
 /*
  * Clean up an entry with the same name
  */
 static int efi_pstore_erase_func(struct efivar_entry *entry, void *data)
 {
-       struct pstore_erase_data *ed = data;
+       efi_char16_t *efi_name = data;
        efi_guid_t vendor = LINUX_EFI_CRASH_GUID;
-       efi_char16_t efi_name_old[DUMP_NAME_LEN];
-       efi_char16_t *efi_name = ed->name;
-       unsigned long ucs2_len = ucs2_strlen(ed->name);
-       char name_old[DUMP_NAME_LEN];
-       int i;
+       unsigned long ucs2_len = ucs2_strlen(efi_name);
 
        if (efi_guidcmp(entry->var.VendorGuid, vendor))
                return 0;
 
-       if (ucs2_strncmp(entry->var.VariableName,
-                         efi_name, (size_t)ucs2_len)) {
-               /*
-                * Check if an old format, which doesn't support
-                * holding multiple logs, remains.
-                */
-               snprintf(name_old, sizeof(name_old), "dump-type%u-%u-%lu",
-                       ed->record->type, ed->record->part,
-                       ed->record->time.tv_sec);
-
-               for (i = 0; i < DUMP_NAME_LEN; i++)
-                       efi_name_old[i] = name_old[i];
-
-               if (ucs2_strncmp(entry->var.VariableName, efi_name_old,
-                                 ucs2_strlen(efi_name_old)))
-                       return 0;
-       }
+       if (ucs2_strncmp(entry->var.VariableName, efi_name, (size_t)ucs2_len))
+               return 0;
 
        if (entry->scanning) {
                /*
@@ -321,35 +300,48 @@ static int efi_pstore_erase_func(struct efivar_entry *entry, void *data)
        return 1;
 }
 
-static int efi_pstore_erase(struct pstore_record *record)
+static int efi_pstore_erase_name(const char *name)
 {
-       struct pstore_erase_data edata;
        struct efivar_entry *entry = NULL;
-       char name[DUMP_NAME_LEN];
        efi_char16_t efi_name[DUMP_NAME_LEN];
        int found, i;
 
-       snprintf(name, sizeof(name), "dump-type%u-%u-%d-%lu",
-                record->type, record->part, record->count,
-                record->time.tv_sec);
-
-       for (i = 0; i < DUMP_NAME_LEN; i++)
+       for (i = 0; i < DUMP_NAME_LEN; i++) {
                efi_name[i] = name[i];
-
-       edata.record = record;
-       edata.name = efi_name;
+               if (name[i] == '\0')
+                       break;
+       }
 
        if (efivar_entry_iter_begin())
                return -EINTR;
-       found = __efivar_entry_iter(efi_pstore_erase_func, &efivar_sysfs_list, &edata, &entry);
 
-       if (found && !entry->scanning) {
-               efivar_entry_iter_end();
+       found = __efivar_entry_iter(efi_pstore_erase_func, &efivar_sysfs_list,
+                                   efi_name, &entry);
+       efivar_entry_iter_end();
+
+       if (found && !entry->scanning)
                efivar_unregister(entry);
-       } else
-               efivar_entry_iter_end();
 
-       return 0;
+       return found ? 0 : -ENOENT;
+}
+
+static int efi_pstore_erase(struct pstore_record *record)
+{
+       char name[DUMP_NAME_LEN];
+       int ret;
+
+       snprintf(name, sizeof(name), "dump-type%u-%u-%d-%lu",
+                record->type, record->part, record->count,
+                record->time.tv_sec);
+       ret = efi_pstore_erase_name(name);
+       if (ret != -ENOENT)
+               return ret;
+
+       snprintf(name, sizeof(name), "dump-type%u-%u-%lu",
+               record->type, record->part, record->time.tv_sec);
+       ret = efi_pstore_erase_name(name);
+
+       return ret;
 }
 
 static struct pstore_info efi_pstore_info = {