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 <sourabhj...@linux.ibm.com>
---
 .../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:       linuxppc-dev@lists.ozlabs.org
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

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