From fdeadb43fdf1e7d5698c027b555c389174548e5a Mon Sep 17 00:00:00 2001 From: Madper Xie Date: Fri, 29 Nov 2013 15:58:57 +0800 Subject: [PATCH] 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 Cc: Seiji Aguchi Cc: stable@vger.kernel.org Signed-off-by: Matt Fleming --- drivers/firmware/efi/efi-pstore.c | 20 ++++++++++++++------ 1 file changed, 14 insertions(+), 6 deletions(-) diff --git a/drivers/firmware/efi/efi-pstore.c b/drivers/firmware/efi/efi-pstore.c index 6ce31e93da55..743fd426f21b 100644 --- a/drivers/firmware/efi/efi-pstore.c +++ b/drivers/firmware/efi/efi-pstore.c @@ -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; -- 2.39.5