As the number of FADump sysfs files increases it is hard to manage all of
them inside /sys/kernel directory. It's better to have all the FADump
related sysfs files in a dedicated directory /sys/kernel/fadump. But in
order to maintain backward compatibility a symlink has been added for every
sysfs that has moved to new location.
As the FADump sysfs files are now part of a dedicated directory there is no
need to prefix their name with fadump_, hence sysfs file names are also
updated. For example fadump_enabled sysfs file is now referred as enabled.
Also consolidate ABI documentation for all the FADump sysfs files in a
single file Documentation/ABI/testing/sysfs-kernel-fadump.
Signed-off-by: Sourabh Jain
---
Documentation/ABI/testing/sysfs-kernel-fadump | 33 +
arch/powerpc/kernel/fadump.c | 118 +-
2 files changed, 117 insertions(+), 34 deletions(-)
create mode 100644 Documentation/ABI/testing/sysfs-kernel-fadump
diff --git a/Documentation/ABI/testing/sysfs-kernel-fadump
b/Documentation/ABI/testing/sysfs-kernel-fadump
new file mode 100644
index ..5d988b919e81
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-kernel-fadump
@@ -0,0 +1,33 @@
+What: /sys/kernel/fadump/*
+Date: Dec 2019
+Contact: linuxppc-dev@lists.ozlabs.org
+Description:
+ The /sys/kernel/fadump/* is a collection of FADump sysfs
+ file provide information about the configuration status
+ of Firmware Assisted Dump (FADump).
+
+What: /sys/kernel/fadump/enabled
+Date: Dec 2019
+Contact: linuxppc-dev@lists.ozlabs.org
+Description: read only
+ Primarily used to identify whether the FADump is enabled in
+ the kernel or not.
+User: Kdump service
+
+What: /sys/kernel/fadump/registered
+Date: Dec 2019
+Contact: linuxppc-dev@lists.ozlabs.org
+Description: read/write
+ Helps to control the dump collect feature from userspace.
+ Setting 1 to this file enables the system to collect the
+ dump and 0 to disable it.
+User: Kdump service
+
+What: /sys/kernel/fadump/release_mem
+Date: Dec 2019
+Contact: linuxppc-dev@lists.ozlabs.org
+Description: write only
+ This is a special sysfs file and only available when
+ the system is booted to capture the vmcore using FADump.
+ It is used to release the memory reserved by FADump to
+ save the crash dump.
diff --git a/arch/powerpc/kernel/fadump.c b/arch/powerpc/kernel/fadump.c
index ed59855430b9..23f15bfea512 100644
--- a/arch/powerpc/kernel/fadump.c
+++ b/arch/powerpc/kernel/fadump.c
@@ -36,6 +36,8 @@ static struct fw_dump fw_dump;
static void __init fadump_reserve_crash_area(u64 base);
+struct kobject *fadump_kobj;
+
#ifndef CONFIG_PRESERVE_FA_DUMP
static DEFINE_MUTEX(fadump_mutex);
struct fadump_mrange_info crash_mrange_info = { "crash", NULL, 0, 0, 0 };
@@ -1323,9 +1325,9 @@ static void fadump_invalidate_release_mem(void)
fw_dump.ops->fadump_init_mem_struct(_dump);
}
-static ssize_t fadump_release_memory_store(struct kobject *kobj,
- struct kobj_attribute *attr,
- const char *buf, size_t count)
+static ssize_t release_mem_store(struct kobject *kobj,
+struct kobj_attribute *attr,
+const char *buf, size_t count)
{
int input = -1;
@@ -1350,23 +1352,33 @@ static ssize_t fadump_release_memory_store(struct
kobject *kobj,
return count;
}
-static ssize_t fadump_enabled_show(struct kobject *kobj,
- struct kobj_attribute *attr,
- char *buf)
+/* Release the reserved memory and disable the FADump */
+static void unregister_fadump(void)
+{
+ fadump_cleanup();
+ fadump_release_memory(fw_dump.reserve_dump_area_start,
+ fw_dump.reserve_dump_area_size);
+ fw_dump.fadump_enabled = 0;
+ kobject_put(fadump_kobj);
+}
+
+static ssize_t enabled_show(struct kobject *kobj,
+ struct kobj_attribute *attr,
+ char *buf)
{
return sprintf(buf, "%d\n", fw_dump.fadump_enabled);
}
-static ssize_t fadump_register_show(struct kobject *kobj,
- struct kobj_attribute *attr,
- char *buf)
+static ssize_t registered_show(struct kobject *kobj,
+ struct kobj_attribute *attr,
+ char *buf)
{
return sprintf(buf, "%d\n", fw_dump.dump_registered);
}
-static ssize_t fadump_register_store(struct kobject *kobj,
- struct kobj_attribute *attr,
-
