diff options
Diffstat (limited to 'drivers/net/netconsole.c')
| -rw-r--r-- | drivers/net/netconsole.c | 66 |
1 files changed, 66 insertions, 0 deletions
diff --git a/drivers/net/netconsole.c b/drivers/net/netconsole.c index 89afe127b46c..e3722de08ea9 100644 --- a/drivers/net/netconsole.c +++ b/drivers/net/netconsole.c @@ -113,6 +113,8 @@ enum sysdata_feature { SYSDATA_TASKNAME = BIT(1), /* Kernel release/version as part of sysdata */ SYSDATA_RELEASE = BIT(2), + /* Include a per-target message ID as part of sysdata */ + SYSDATA_MSGID = BIT(3), }; /** @@ -123,6 +125,7 @@ enum sysdata_feature { * @extradata_complete: Cached, formatted string of append * @userdata_length: String length of usedata in extradata_complete. * @sysdata_fields: Sysdata features enabled. + * @msgcounter: Message sent counter. * @stats: Packet send stats for the target. Used for debugging. * @enabled: On / off knob to enable / disable target. * Visible from userspace (read-write). @@ -153,6 +156,8 @@ struct netconsole_target { size_t userdata_length; /* bit-wise with sysdata_feature bits */ u32 sysdata_fields; + /* protected by target_list_lock */ + u32 msgcounter; #endif struct netconsole_target_stats stats; bool enabled; @@ -504,6 +509,19 @@ static void unregister_netcons_consoles(void) unregister_console(&netconsole); } +static ssize_t sysdata_msgid_enabled_show(struct config_item *item, + char *buf) +{ + struct netconsole_target *nt = to_target(item->ci_parent); + bool msgid_enabled; + + mutex_lock(&dynamic_netconsole_mutex); + msgid_enabled = !!(nt->sysdata_fields & SYSDATA_MSGID); + mutex_unlock(&dynamic_netconsole_mutex); + + return sysfs_emit(buf, "%d\n", msgid_enabled); +} + /* * This one is special -- targets created through the configfs interface * are not enabled (and the corresponding netpoll activated) by default. @@ -799,6 +817,8 @@ static size_t count_extradata_entries(struct netconsole_target *nt) entries += 1; if (nt->sysdata_fields & SYSDATA_RELEASE) entries += 1; + if (nt->sysdata_fields & SYSDATA_MSGID) + entries += 1; return entries; } @@ -935,6 +955,40 @@ static void disable_sysdata_feature(struct netconsole_target *nt, nt->extradata_complete[nt->userdata_length] = 0; } +static ssize_t sysdata_msgid_enabled_store(struct config_item *item, + const char *buf, size_t count) +{ + struct netconsole_target *nt = to_target(item->ci_parent); + bool msgid_enabled, curr; + ssize_t ret; + + ret = kstrtobool(buf, &msgid_enabled); + if (ret) + return ret; + + mutex_lock(&dynamic_netconsole_mutex); + curr = !!(nt->sysdata_fields & SYSDATA_MSGID); + if (msgid_enabled == curr) + goto unlock_ok; + + if (msgid_enabled && + count_extradata_entries(nt) >= MAX_EXTRADATA_ITEMS) { + ret = -ENOSPC; + goto unlock; + } + + if (msgid_enabled) + nt->sysdata_fields |= SYSDATA_MSGID; + else + disable_sysdata_feature(nt, SYSDATA_MSGID); + +unlock_ok: + ret = strnlen(buf, count); +unlock: + mutex_unlock(&dynamic_netconsole_mutex); + return ret; +} + static ssize_t sysdata_release_enabled_store(struct config_item *item, const char *buf, size_t count) { @@ -1050,6 +1104,7 @@ CONFIGFS_ATTR(userdatum_, value); CONFIGFS_ATTR(sysdata_, cpu_nr_enabled); CONFIGFS_ATTR(sysdata_, taskname_enabled); CONFIGFS_ATTR(sysdata_, release_enabled); +CONFIGFS_ATTR(sysdata_, msgid_enabled); static struct configfs_attribute *userdatum_attrs[] = { &userdatum_attr_value, @@ -1112,6 +1167,7 @@ static struct configfs_attribute *userdata_attrs[] = { &sysdata_attr_cpu_nr_enabled, &sysdata_attr_taskname_enabled, &sysdata_attr_release_enabled, + &sysdata_attr_msgid_enabled, NULL, }; @@ -1309,6 +1365,14 @@ static int sysdata_append_release(struct netconsole_target *nt, int offset) init_utsname()->release); } +static int sysdata_append_msgid(struct netconsole_target *nt, int offset) +{ + wrapping_assign_add(nt->msgcounter, 1); + return scnprintf(&nt->extradata_complete[offset], + MAX_EXTRADATA_ENTRY_LEN, " msgid=%u\n", + nt->msgcounter); +} + /* * prepare_extradata - append sysdata at extradata_complete in runtime * @nt: target to send message to @@ -1331,6 +1395,8 @@ static int prepare_extradata(struct netconsole_target *nt) extradata_len += sysdata_append_taskname(nt, extradata_len); if (nt->sysdata_fields & SYSDATA_RELEASE) extradata_len += sysdata_append_release(nt, extradata_len); + if (nt->sysdata_fields & SYSDATA_MSGID) + extradata_len += sysdata_append_msgid(nt, extradata_len); WARN_ON_ONCE(extradata_len > MAX_EXTRADATA_ENTRY_LEN * MAX_EXTRADATA_ITEMS); |