lkml.org 
[lkml]   [2012]   [Oct]   [30]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH v4 6/7] efi_pstore: Add a format check for an existing variable name at reading time
Date

[Issue]

a format of variable name has been updated to type, id, count and ctime
to support holding multiple logs.

Format of current variable name
dump-type0-1-2-12345678

type:0
id:1
count:2
ctime:12345678

On the other hand, if an old variable name before being updated
remains, users can't read it via /dev/pstore.

Format of old variable name
dump-type0-1-12345678

type:0
id:1
ctime:12345678

[Solution]

This patch add a format check for the old variable name in a read callback
to make it readable.

Signed-off-by: Seiji Aguchi <seiji.aguchi@hds.com>
---
drivers/firmware/efivars.c | 38 ++++++++++++++++++++++++++++----------
1 files changed, 28 insertions(+), 10 deletions(-)

diff --git a/drivers/firmware/efivars.c b/drivers/firmware/efivars.c
index 7ad3aae..bf7a6f9 100644
--- a/drivers/firmware/efivars.c
+++ b/drivers/firmware/efivars.c
@@ -681,17 +681,35 @@ static ssize_t efi_pstore_read(u64 *id, enum pstore_type_id *type,
*count = cnt;
timespec->tv_sec = time;
timespec->tv_nsec = 0;
- get_var_data_locked(efivars, &efivars->walk_entry->var);
- size = efivars->walk_entry->var.DataSize;
- *buf = kmalloc(size, GFP_KERNEL);
- if (*buf == NULL)
- return -ENOMEM;
- memcpy(*buf, efivars->walk_entry->var.Data,
- size);
- efivars->walk_entry = list_entry(efivars->walk_entry->list.next,
- struct efivar_entry, list);
- return size;
+ } else if (sscanf(name, "dump-type%u-%u-%lu",
+ type, &part, &time) == 3) {
+ /*
+ * Check if an old format,
+ * which doesn't support holding
+ * multiple logs, remains.
+ */
+ *id = part;
+ *count = 0;
+ timespec->tv_sec = time;
+ timespec->tv_nsec = 0;
+ } else {
+ efivars->walk_entry = list_entry(
+ efivars->walk_entry->list.next,
+ struct efivar_entry, list);
+ continue;
}
+
+ get_var_data_locked(efivars, &efivars->walk_entry->var);
+ size = efivars->walk_entry->var.DataSize;
+ *buf = kmalloc(size, GFP_KERNEL);
+ if (*buf == NULL)
+ return -ENOMEM;
+ memcpy(*buf, efivars->walk_entry->var.Data,
+ size);
+ efivars->walk_entry = list_entry(
+ efivars->walk_entry->list.next,
+ struct efivar_entry, list);
+ return size;
}
efivars->walk_entry = list_entry(efivars->walk_entry->list.next,
struct efivar_entry, list);
--
1.7.1

\
 
 \ /
  Last update: 2012-10-30 21:21    [W:0.030 / U:0.816 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site