Currently, FADump sysfs files are present inside /sys/kernel directory.
But as the number of FADump sysfs file increases it is not a good idea to
push all of them in /sys/kernel directory. It is better to have separate
directory to keep all the FADump sysfs files.
Patch series reorganizes the FADump sysfs files and avail all the existing
FADump sysfs files present inside /sys/kernel into a new directory
/sys/kernel/fadump. The backward compatibility is maintained by adding a
symlink for every sysfs file that has moved to new location. Also a new
FADump sys interface is added to get the amount of memory reserved by FADump
for saving the crash dump.
Changelog:
v1 -> v5:
- https://lists.ozlabs.org/pipermail/linuxppc-dev/2019-December/201642.html
v5 -> v6
- Unregister FADump if fadump group creation fails.
- Remove fadump_enabled symlink if fadump_registered symlink
creation fails.
- Removed CREATE_SYMLINK macro.
Sourabh Jain (6):
Documentation/ABI: add ABI documentation for /sys/kernel/fadump_*
sysfs: wrap __compat_only_sysfs_link_entry_to_kobj function to change
the symlink name
powerpc/fadump: reorganize /sys/kernel/fadump_* sysfs files
powerpc/powernv: move core and fadump_release_opalcore under new
kobject
Documentation/ABI: mark /sys/kernel/fadump_* sysfs files deprecated
powerpc/fadump: sysfs for fadump memory reservation
.../ABI/obsolete/sysfs-kernel-fadump_enabled | 9 ++
.../obsolete/sysfs-kernel-fadump_registered | 10 ++
.../obsolete/sysfs-kernel-fadump_release_mem | 10 ++
.../sysfs-kernel-fadump_release_opalcore | 9 ++
Documentation/ABI/testing/sysfs-kernel-fadump | 40 ++++++
.../powerpc/firmware-assisted-dump.rst | 28 +++-
arch/powerpc/kernel/fadump.c | 127 +++++++++++++-----
arch/powerpc/platforms/powernv/opal-core.c | 55 +++++---
fs/sysfs/group.c | 28 +++-
include/linux/sysfs.h | 12 ++
10 files changed, 270 insertions(+), 58 deletions(-)
create mode 100644 Documentation/ABI/obsolete/sysfs-kernel-fadump_enabled
create mode 100644 Documentation/ABI/obsolete/sysfs-kernel-fadump_registered
create mode 100644 Documentation/ABI/obsolete/sysfs-kernel-fadump_release_mem
create mode 100644 Documentation/ABI/removed/sysfs-kernel-fadump_release_opalcore
create mode 100644 Documentation/ABI/testing/sysfs-kernel-fadump
--
2.17.2
Add a deprecation note in FADump sysfs ABI documentation files and move
them from ABI/testing to ABI/obsolete directory.
Signed-off-by: Sourabh Jain <[email protected]>
---
.../ABI/{testing => obsolete}/sysfs-kernel-fadump_enabled | 2 ++
.../{testing => obsolete}/sysfs-kernel-fadump_registered | 2 ++
.../{testing => obsolete}/sysfs-kernel-fadump_release_mem | 2 ++
Documentation/powerpc/firmware-assisted-dump.rst | 8 ++++++++
4 files changed, 14 insertions(+)
rename Documentation/ABI/{testing => obsolete}/sysfs-kernel-fadump_enabled (73%)
rename Documentation/ABI/{testing => obsolete}/sysfs-kernel-fadump_registered (77%)
rename Documentation/ABI/{testing => obsolete}/sysfs-kernel-fadump_release_mem (78%)
diff --git a/Documentation/ABI/testing/sysfs-kernel-fadump_enabled b/Documentation/ABI/obsolete/sysfs-kernel-fadump_enabled
similarity index 73%
rename from Documentation/ABI/testing/sysfs-kernel-fadump_enabled
rename to Documentation/ABI/obsolete/sysfs-kernel-fadump_enabled
index f73632b1c006..e9c2de8b3688 100644
--- a/Documentation/ABI/testing/sysfs-kernel-fadump_enabled
+++ b/Documentation/ABI/obsolete/sysfs-kernel-fadump_enabled
@@ -1,3 +1,5 @@
+This ABI is renamed and moved to a new location /sys/kernel/fadump/enabled.
+
What: /sys/kernel/fadump_enabled
Date: Feb 2012
Contact: [email protected]
diff --git a/Documentation/ABI/testing/sysfs-kernel-fadump_registered b/Documentation/ABI/obsolete/sysfs-kernel-fadump_registered
similarity index 77%
rename from Documentation/ABI/testing/sysfs-kernel-fadump_registered
rename to Documentation/ABI/obsolete/sysfs-kernel-fadump_registered
index dcf925e53f0f..0360be39c98e 100644
--- a/Documentation/ABI/testing/sysfs-kernel-fadump_registered
+++ b/Documentation/ABI/obsolete/sysfs-kernel-fadump_registered
@@ -1,3 +1,5 @@
+This ABI is renamed and moved to a new location /sys/kernel/fadump/registered.¬
+
What: /sys/kernel/fadump_registered
Date: Feb 2012
Contact: [email protected]
diff --git a/Documentation/ABI/testing/sysfs-kernel-fadump_release_mem b/Documentation/ABI/obsolete/sysfs-kernel-fadump_release_mem
similarity index 78%
rename from Documentation/ABI/testing/sysfs-kernel-fadump_release_mem
rename to Documentation/ABI/obsolete/sysfs-kernel-fadump_release_mem
index 9c20d64ab48d..6ce0b129ab12 100644
--- a/Documentation/ABI/testing/sysfs-kernel-fadump_release_mem
+++ b/Documentation/ABI/obsolete/sysfs-kernel-fadump_release_mem
@@ -1,3 +1,5 @@
+This ABI is renamed and moved to a new location /sys/kernel/fadump/release_mem.¬
+
What: /sys/kernel/fadump_release_mem
Date: Feb 2012
Contact: [email protected]
diff --git a/Documentation/powerpc/firmware-assisted-dump.rst b/Documentation/powerpc/firmware-assisted-dump.rst
index 345a3405206e..365c10209ef3 100644
--- a/Documentation/powerpc/firmware-assisted-dump.rst
+++ b/Documentation/powerpc/firmware-assisted-dump.rst
@@ -295,6 +295,14 @@ Note: /sys/kernel/fadump_release_opalcore sysfs has moved to
echo 1 > /sys/firmware/opal/mpipl/release_core
+Note: The following FADump sysfs files are deprecated.
+
+ Deprecated Alternative
+ --------------------------------------------------------------------
+ /sys/kernel/fadump_enabled /sys/kernel/fadump/enabled
+ /sys/kernel/fadump_registered /sys/kernel/fadump/registered
+ /sys/kernel/fadump_release_mem /sys/kernel/fadump/release_mem
+
Here is the list of files under powerpc debugfs:
(Assuming debugfs is mounted on /sys/kernel/debug directory.)
--
2.17.2
The /sys/firmware/opal/core and /sys/kernel/fadump_release_opalcore sysfs
files are used to export and release the OPAL memory on PowerNV platform.
let's organize them into a new kobject under /sys/firmware/opal/mpipl/
directory.
A symlink is added to maintain the backward compatibility for
/sys/firmware/opal/core sysfs file.
Signed-off-by: Sourabh Jain <[email protected]>
---
.../sysfs-kernel-fadump_release_opalcore | 2 +
.../powerpc/firmware-assisted-dump.rst | 15 +++--
arch/powerpc/platforms/powernv/opal-core.c | 55 ++++++++++++++-----
3 files changed, 51 insertions(+), 21 deletions(-)
rename Documentation/ABI/{testing => removed}/sysfs-kernel-fadump_release_opalcore (82%)
diff --git a/Documentation/ABI/testing/sysfs-kernel-fadump_release_opalcore b/Documentation/ABI/removed/sysfs-kernel-fadump_release_opalcore
similarity index 82%
rename from Documentation/ABI/testing/sysfs-kernel-fadump_release_opalcore
rename to Documentation/ABI/removed/sysfs-kernel-fadump_release_opalcore
index 53313c1d4e7a..a8d46cd0f4e6 100644
--- a/Documentation/ABI/testing/sysfs-kernel-fadump_release_opalcore
+++ b/Documentation/ABI/removed/sysfs-kernel-fadump_release_opalcore
@@ -1,3 +1,5 @@
+This ABI is moved to /sys/firmware/opal/mpipl/release_core.
+
What: /sys/kernel/fadump_release_opalcore
Date: Sep 2019
Contact: [email protected]
diff --git a/Documentation/powerpc/firmware-assisted-dump.rst b/Documentation/powerpc/firmware-assisted-dump.rst
index 0455a78486d5..345a3405206e 100644
--- a/Documentation/powerpc/firmware-assisted-dump.rst
+++ b/Documentation/powerpc/firmware-assisted-dump.rst
@@ -112,13 +112,13 @@ to ensure that crash data is preserved to process later.
-- On OPAL based machines (PowerNV), if the kernel is build with
CONFIG_OPAL_CORE=y, OPAL memory at the time of crash is also
- exported as /sys/firmware/opal/core file. This procfs file is
+ exported as /sys/firmware/opal/mpipl/core file. This procfs file is
helpful in debugging OPAL crashes with GDB. The kernel memory
used for exporting this procfs file can be released by echo'ing
- '1' to /sys/kernel/fadump_release_opalcore node.
+ '1' to /sys/firmware/opal/mpipl/release_core node.
e.g.
- # echo 1 > /sys/kernel/fadump_release_opalcore
+ # echo 1 > /sys/firmware/opal/mpipl/release_core
Implementation details:
-----------------------
@@ -283,14 +283,17 @@ Here is the list of files under kernel sysfs:
enhanced to use this interface to release the memory reserved for
dump and continue without 2nd reboot.
- /sys/kernel/fadump_release_opalcore
+Note: /sys/kernel/fadump_release_opalcore sysfs has moved to
+ /sys/firmware/opal/mpipl/release_core
+
+ /sys/firmware/opal/mpipl/release_core
This file is available only on OPAL based machines when FADump is
active during capture kernel. This is used to release the memory
- used by the kernel to export /sys/firmware/opal/core file. To
+ used by the kernel to export /sys/firmware/opal/mpipl/core file. To
release this memory, echo '1' to it:
- echo 1 > /sys/kernel/fadump_release_opalcore
+ echo 1 > /sys/firmware/opal/mpipl/release_core
Here is the list of files under powerpc debugfs:
(Assuming debugfs is mounted on /sys/kernel/debug directory.)
diff --git a/arch/powerpc/platforms/powernv/opal-core.c b/arch/powerpc/platforms/powernv/opal-core.c
index ed895d82c048..6dba3b62269f 100644
--- a/arch/powerpc/platforms/powernv/opal-core.c
+++ b/arch/powerpc/platforms/powernv/opal-core.c
@@ -71,6 +71,7 @@ static LIST_HEAD(opalcore_list);
static struct opalcore_config *oc_conf;
static const struct opal_mpipl_fadump *opalc_metadata;
static const struct opal_mpipl_fadump *opalc_cpu_metadata;
+struct kobject *mpipl_kobj;
/*
* Set crashing CPU's signal to SIGUSR1. if the kernel is triggered
@@ -428,7 +429,7 @@ static void opalcore_cleanup(void)
return;
/* Remove OPAL core sysfs file */
- sysfs_remove_bin_file(opal_kobj, &opal_core_attr);
+ sysfs_remove_bin_file(mpipl_kobj, &opal_core_attr);
oc_conf->ptload_phdr = NULL;
oc_conf->ptload_cnt = 0;
@@ -563,9 +564,9 @@ static void __init opalcore_config_init(void)
of_node_put(np);
}
-static ssize_t fadump_release_opalcore_store(struct kobject *kobj,
- struct kobj_attribute *attr,
- const char *buf, size_t count)
+static ssize_t release_core_store(struct kobject *kobj,
+ struct kobj_attribute *attr,
+ const char *buf, size_t count)
{
int input = -1;
@@ -589,9 +590,23 @@ static ssize_t fadump_release_opalcore_store(struct kobject *kobj,
return count;
}
-static struct kobj_attribute opalcore_rel_attr = __ATTR(fadump_release_opalcore,
- 0200, NULL,
- fadump_release_opalcore_store);
+static struct kobj_attribute opalcore_rel_attr = __ATTR_WO(release_core);
+
+static struct attribute *mpipl_attr[] = {
+ &opalcore_rel_attr.attr,
+ NULL,
+};
+
+static struct bin_attribute *mpipl_bin_attr[] = {
+ &opal_core_attr,
+ NULL,
+
+};
+
+static struct attribute_group mpipl_group = {
+ .attrs = mpipl_attr,
+ .bin_attrs = mpipl_bin_attr,
+};
static int __init opalcore_init(void)
{
@@ -609,7 +624,7 @@ static int __init opalcore_init(void)
* then capture the dump.
*/
if (!(is_opalcore_usable())) {
- pr_err("Failed to export /sys/firmware/opal/core\n");
+ pr_err("Failed to export /sys/firmware/opal/mpipl/core\n");
opalcore_cleanup();
return rc;
}
@@ -617,18 +632,28 @@ static int __init opalcore_init(void)
/* Set OPAL core file size */
opal_core_attr.size = oc_conf->opalcore_size;
+ mpipl_kobj = kobject_create_and_add("mpipl", opal_kobj);
+ if (!mpipl_kobj) {
+ pr_err("unable to create mpipl kobject\n");
+ return -ENOMEM;
+ }
+
/* Export OPAL core sysfs file */
- rc = sysfs_create_bin_file(opal_kobj, &opal_core_attr);
- if (rc != 0) {
- pr_err("Failed to export /sys/firmware/opal/core\n");
+ rc = sysfs_create_group(mpipl_kobj, &mpipl_group);
+ if (rc) {
+ pr_err("mpipl sysfs group creation failed (%d)", rc);
opalcore_cleanup();
return rc;
}
-
- rc = sysfs_create_file(kernel_kobj, &opalcore_rel_attr.attr);
+ /* The /sys/firmware/opal/core is moved to /sys/firmware/opal/mpipl/
+ * directory, need to create symlink at old location to maintain
+ * backward compatibility.
+ */
+ rc = compat_only_sysfs_link_entry_to_kobj(opal_kobj, mpipl_kobj,
+ "core", NULL);
if (rc) {
- pr_warn("unable to create sysfs file fadump_release_opalcore (%d)\n",
- rc);
+ pr_err("unable to create core symlink (%d)\n", rc);
+ return rc;
}
return 0;
--
2.17.2