[PATCH 7/8] Read of-config partition via pstore

From: Aruna Balakrishnaiah
Date: Wed Apr 10 2013 - 03:24:24 EST


This patch exploits pstore infrastructure to read the details
from NVRAM's of-config partition.

Signed-off-by: Aruna Balakrishnaiah <aruna@xxxxxxxxxxxxxxxxxx>
Reviewed-by: Jim Keniston <jkenisto@xxxxxxxxxx>
---
arch/powerpc/platforms/pseries/nvram.c | 58 ++++++++++++++++++++++++++------
fs/pstore/inode.c | 3 ++
include/linux/pstore.h | 1 +
3 files changed, 52 insertions(+), 10 deletions(-)

diff --git a/arch/powerpc/platforms/pseries/nvram.c b/arch/powerpc/platforms/pseries/nvram.c
index 6a3a7cd..b65a670 100644
--- a/arch/powerpc/platforms/pseries/nvram.c
+++ b/arch/powerpc/platforms/pseries/nvram.c
@@ -78,6 +78,14 @@ static const char *pseries_nvram_os_partitions[] = {
NULL
};

+#ifdef CONFIG_PSTORE
+static struct nvram_os_partition of_config_partition = {
+ .name = "of-config",
+ .index = -1,
+ .os_partition = false
+};
+#endif
+
struct oops_log_info {
u16 version;
u16 report_length;
@@ -148,6 +156,7 @@ static size_t oops_data_sz;
static enum pstore_type_id nvram_type_ids[] = {
PSTORE_TYPE_DMESG,
PSTORE_TYPE_RTAS,
+ PSTORE_TYPE_OF,
-1
};
static int read_type;
@@ -350,11 +359,15 @@ int nvram_read_partition(struct nvram_os_partition *part, char *buff,

tmp_index = part->index;

- rc = ppc_md.nvram_read((char *)&info, sizeof(struct err_log_info), &tmp_index);
- if (rc <= 0) {
- printk(KERN_ERR "nvram_read_partition: "
- "Failed nvram_read (%d)\n", rc);
- return rc;
+ if (part->os_partition) {
+ rc = ppc_md.nvram_read((char *)&info,
+ sizeof(struct err_log_info),
+ &tmp_index);
+ if (rc <= 0) {
+ printk(KERN_ERR "nvram_read_partition: "
+ "Failed nvram_read (%d)\n", rc);
+ return rc;
+ }
}

rc = ppc_md.nvram_read(buff, length, &tmp_index);
@@ -364,8 +377,10 @@ int nvram_read_partition(struct nvram_os_partition *part, char *buff,
return rc;
}

- *error_log_cnt = info.seq_num;
- *err_type = info.error_type;
+ if (part->os_partition) {
+ *error_log_cnt = info.seq_num;
+ *err_type = info.error_type;
+ }

return 0;
}
@@ -755,7 +770,7 @@ static int nvram_pstore_write(enum pstore_type_id type,
}

/*
- * Reads the oops/panic report and ibm,rtas-log partition.
+ * Reads the oops/panic report, rtas-log and of-config partition.
* Returns the length of the data we read from each partition.
* Returns 0 if we've been called before.
*/
@@ -764,9 +779,11 @@ static ssize_t nvram_pstore_read(u64 *id, enum pstore_type_id *type,
struct pstore_info *psi)
{
struct oops_log_info *oops_hdr;
- unsigned int err_type, id_no;
+ unsigned int err_type, id_no, size = 0;
struct nvram_os_partition *part = NULL;
char *buff = NULL;
+ int sig = 0;
+ loff_t p;

read_type++;

@@ -781,10 +798,29 @@ static ssize_t nvram_pstore_read(u64 *id, enum pstore_type_id *type,
time->tv_sec = last_rtas_event;
time->tv_nsec = 0;
break;
+ case PSTORE_TYPE_OF:
+ sig = NVRAM_SIG_OF;
+ part = &of_config_partition;
+ *type = PSTORE_TYPE_OF;
+ *id = PSTORE_TYPE_OF;
+ time->tv_sec = 0;
+ time->tv_nsec = 0;
+ break;
default:
return 0;
}

+ if (!part->os_partition) {
+ p = nvram_find_partition(part->name, sig, &size);
+ if (p <= 0) {
+ pr_err("nvram: Failed to find partition %s, "
+ "err %d\n", part->name, (int)p);
+ return 0;
+ }
+ part->index = p;
+ part->size = size;
+ }
+
buff = kmalloc(part->size, GFP_KERNEL);

if (!buff)
@@ -796,7 +832,9 @@ static ssize_t nvram_pstore_read(u64 *id, enum pstore_type_id *type,
}

*count = 0;
- *id = id_no;
+
+ if (part->os_partition)
+ *id = id_no;

if (nvram_type_ids[read_type] == PSTORE_TYPE_DMESG) {
oops_hdr = (struct oops_log_info *)buff;
diff --git a/fs/pstore/inode.c b/fs/pstore/inode.c
index 59b1454..c3d1846 100644
--- a/fs/pstore/inode.c
+++ b/fs/pstore/inode.c
@@ -327,6 +327,9 @@ int pstore_mkfile(enum pstore_type_id type, char *psname, u64 id, int count,
case PSTORE_TYPE_RTAS:
sprintf(name, "rtas-%s-%lld", psname, id);
break;
+ case PSTORE_TYPE_OF:
+ sprintf(name, "of-%s-%lld", psname, id);
+ break;
case PSTORE_TYPE_UNKNOWN:
sprintf(name, "unknown-%s-%lld", psname, id);
break;
diff --git a/include/linux/pstore.h b/include/linux/pstore.h
index 4eb94c9..a23d7d2 100644
--- a/include/linux/pstore.h
+++ b/include/linux/pstore.h
@@ -37,6 +37,7 @@ enum pstore_type_id {
PSTORE_TYPE_FTRACE = 3,
/* PPC64 partition types */
PSTORE_TYPE_RTAS = 10,
+ PSTORE_TYPE_OF = 11,
PSTORE_TYPE_UNKNOWN = 255
};


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