lkml.org 
[lkml]   [2021]   [Dec]   [1]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH] powerpc/pseries: read the lpar name from the firmware
Date
The LPAR name may be changed after the LPAR has been started in the HMC.
In that case lparstat command is not reporting the updated value because it
reads it from the device tree which is read at boot time.

However this value could be read from RTAS.

Adding this value in the /proc/powerpc/lparcfg output allows to read the
updated value.

Signed-off-by: Laurent Dufour <ldufour@linux.ibm.com>
---
arch/powerpc/platforms/pseries/lparcfg.c | 50 ++++++++++++++++++++++++
1 file changed, 50 insertions(+)

diff --git a/arch/powerpc/platforms/pseries/lparcfg.c b/arch/powerpc/platforms/pseries/lparcfg.c
index f71eac74ea92..b597b132ce32 100644
--- a/arch/powerpc/platforms/pseries/lparcfg.c
+++ b/arch/powerpc/platforms/pseries/lparcfg.c
@@ -311,6 +311,55 @@ static void parse_mpp_x_data(struct seq_file *m)
seq_printf(m, "coalesce_pool_spurr=%ld\n", mpp_x_data.pool_spurr_cycles);
}

+/*
+ * PAPR defines no maximum for the LPAR name, and defines that the maximum
+ * length of the get-system-parameter's output buffer is 4000 plus 2 bytes for
+ * the length. Limit LPAR's name size to 1024
+ */
+#define SPLPAR_LPAR_NAME_MAXLEN 1026
+#define SPLPAR_LPAR_NAME_TOKEN 55
+static void parse_lpar_name(struct seq_file *m)
+{
+ int call_status, len;
+ unsigned char *local_buffer;
+
+ local_buffer = kmalloc(SPLPAR_LPAR_NAME_MAXLEN, GFP_KERNEL);
+ if (!local_buffer) {
+ pr_err("%s %s kmalloc failure at line %d\n",
+ __FILE__, __func__, __LINE__);
+ return;
+ }
+
+ spin_lock(&rtas_data_buf_lock);
+ memset(rtas_data_buf, 0, RTAS_DATA_BUF_SIZE);
+ call_status = rtas_call(rtas_token("ibm,get-system-parameter"), 3, 1,
+ NULL,
+ SPLPAR_LPAR_NAME_TOKEN,
+ __pa(rtas_data_buf),
+ RTAS_DATA_BUF_SIZE);
+ memcpy(local_buffer, rtas_data_buf, SPLPAR_LPAR_NAME_MAXLEN);
+ spin_unlock(&rtas_data_buf_lock);
+
+ if (call_status != 0) {
+ pr_err("%s %s Error calling get-system-parameter (0x%x)\n",
+ __FILE__, __func__, call_status);
+ } else {
+ local_buffer[SPLPAR_LPAR_NAME_MAXLEN - 1] = '\0';
+ len = local_buffer[0] * 256 + local_buffer[1];
+
+ /*
+ * Forces an empty string in the weird case fw reports no data.
+ */
+ if (!len)
+ local_buffer[2] = '\0';
+
+ seq_printf(m, "lpar_name=%s\n", local_buffer + 2);
+ }
+
+ kfree(local_buffer);
+}
+
+
#define SPLPAR_CHARACTERISTICS_TOKEN 20
#define SPLPAR_MAXLENGTH 1026*(sizeof(char))

@@ -496,6 +545,7 @@ static int pseries_lparcfg_data(struct seq_file *m, void *v)

if (firmware_has_feature(FW_FEATURE_SPLPAR)) {
/* this call handles the ibm,get-system-parameter contents */
+ parse_lpar_name(m);
parse_system_parameter_string(m);
parse_ppp_data(m);
parse_mpp_data(m);
--
2.34.1
\
 
 \ /
  Last update: 2021-12-01 15:49    [W:0.050 / U:0.108 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site