efi-pstore: Make efi-pstore return a unique id

Pstore fs expects that backends provide a unique id which could avoid
pstore making entries as duplication or denominating entries the same
name. So I combine the timestamp, part and count into id.

Signed-off-by: Madper Xie <cxie@redhat.com>
Cc: Seiji Aguchi <seiji.aguchi@hds.com>
Cc: stable@vger.kernel.org
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
This commit is contained in:
Madper Xie 2013-11-29 15:58:57 +08:00 committed by Matt Fleming
parent 1f3a8bae21
commit fdeadb43fd

View file

@ -37,6 +37,12 @@ struct pstore_read_data {
char **buf;
};
static inline u64 generic_id(unsigned long timestamp,
unsigned int part, int count)
{
return (timestamp * 100 + part) * 1000 + count;
}
static int efi_pstore_read_func(struct efivar_entry *entry, void *data)
{
efi_guid_t vendor = LINUX_EFI_CRASH_GUID;
@ -55,7 +61,7 @@ static int efi_pstore_read_func(struct efivar_entry *entry, void *data)
if (sscanf(name, "dump-type%u-%u-%d-%lu-%c",
cb_data->type, &part, &cnt, &time, &data_type) == 5) {
*cb_data->id = part;
*cb_data->id = generic_id(time, part, cnt);
*cb_data->count = cnt;
cb_data->timespec->tv_sec = time;
cb_data->timespec->tv_nsec = 0;
@ -65,7 +71,7 @@ static int efi_pstore_read_func(struct efivar_entry *entry, void *data)
*cb_data->compressed = false;
} else if (sscanf(name, "dump-type%u-%u-%d-%lu",
cb_data->type, &part, &cnt, &time) == 4) {
*cb_data->id = part;
*cb_data->id = generic_id(time, part, cnt);
*cb_data->count = cnt;
cb_data->timespec->tv_sec = time;
cb_data->timespec->tv_nsec = 0;
@ -77,7 +83,7 @@ static int efi_pstore_read_func(struct efivar_entry *entry, void *data)
* which doesn't support holding
* multiple logs, remains.
*/
*cb_data->id = part;
*cb_data->id = generic_id(time, part, 0);
*cb_data->count = 0;
cb_data->timespec->tv_sec = time;
cb_data->timespec->tv_nsec = 0;
@ -320,14 +326,16 @@ static int efi_pstore_erase(enum pstore_type_id type, u64 id, int count,
char name[DUMP_NAME_LEN];
efi_char16_t efi_name[DUMP_NAME_LEN];
int found, i;
unsigned int part;
sprintf(name, "dump-type%u-%u-%d-%lu", type, (unsigned int)id, count,
time.tv_sec);
do_div(id, 1000);
part = do_div(id, 100);
sprintf(name, "dump-type%u-%u-%d-%lu", type, part, count, time.tv_sec);
for (i = 0; i < DUMP_NAME_LEN; i++)
efi_name[i] = name[i];
edata.id = id;
edata.id = part;
edata.type = type;
edata.count = count;
edata.time = time;