LinuxPPC-Dev Archive on lore.kernel.org
 help / color / Atom feed
From: Sourabh Jain <sourabhjain@linux.ibm.com>
To: mpe@ellerman.id.au
Cc: corbet@lwn.net, mahesh@linux.vnet.ibm.com,
	linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org,
	Sourabh Jain <sourabhjain@linux.ibm.com>,
	linuxppc-dev@ozlabs.org, hbathini@linux.ibm.com
Subject: [PATCH v3 2/4] powerpc/fadump: reorganize /sys/kernel/fadump_* sysfs files
Date: Sat,  9 Nov 2019 17:53:37 +0530
Message-ID: <20191109122339.20484-3-sourabhjain@linux.ibm.com> (raw)
In-Reply-To: <20191109122339.20484-1-sourabhjain@linux.ibm.com>

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 the backward compatibility the /sys/kernel/fadump_*
sysfs files are replicated inside /sys/kernel/fadump/ and eventually get
removed in future.

As the FADump sysfs files are now part of 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 <sourabhjain@linux.ibm.com>
---
 Documentation/ABI/testing/sysfs-kernel-fadump | 41 +++++++++++++++++++
 arch/powerpc/kernel/fadump.c                  | 38 +++++++++++++++++
 arch/powerpc/platforms/powernv/opal-core.c    | 10 +++--
 3 files changed, 86 insertions(+), 3 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 000000000000..a77f1a5ba389
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-kernel-fadump
@@ -0,0 +1,41 @@
+What:		/sys/kernel/fadump/*
+Date:		Nov 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:		Nov 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:		Nov 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:		Nov 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.
+
+What:		/sys/kernel/fadump/release_opalcore
+Date:		Nov 2019
+Contact:	linuxppc-dev@lists.ozlabs.org
+Description:	write only
+		The sysfs file is available when the system is booted to
+		collect the dump on OPAL based machine. It used to release
+		the memory used to collect the opalcore.
diff --git a/arch/powerpc/kernel/fadump.c b/arch/powerpc/kernel/fadump.c
index ed59855430b9..a9591def0c84 100644
--- a/arch/powerpc/kernel/fadump.c
+++ b/arch/powerpc/kernel/fadump.c
@@ -1418,6 +1418,9 @@ static int fadump_region_show(struct seq_file *m, void *private)
 	return 0;
 }
 
+struct kobject *fadump_kobj;
+EXPORT_SYMBOL_GPL(fadump_kobj);
+
 static struct kobj_attribute fadump_release_attr = __ATTR(fadump_release_mem,
 						0200, NULL,
 						fadump_release_memory_store);
@@ -1428,6 +1431,16 @@ static struct kobj_attribute fadump_register_attr = __ATTR(fadump_registered,
 						0644, fadump_register_show,
 						fadump_register_store);
 
+static struct kobj_attribute release_attr = __ATTR(release_mem,
+						0200, NULL,
+						fadump_release_memory_store);
+static struct kobj_attribute enable_attr = __ATTR(enabled,
+						0444, fadump_enabled_show,
+						NULL);
+static struct kobj_attribute register_attr = __ATTR(registered,
+						0644, fadump_register_show,
+						fadump_register_store);
+
 DEFINE_SHOW_ATTRIBUTE(fadump_region);
 
 static void fadump_init_files(void)
@@ -1435,6 +1448,11 @@ static void fadump_init_files(void)
 	struct dentry *debugfs_file;
 	int rc = 0;
 
+	fadump_kobj = kobject_create_and_add("fadump", kernel_kobj);
+	if (!fadump_kobj) {
+		pr_err("failed to create fadump kobject\n");
+		return;
+	}
 	rc = sysfs_create_file(kernel_kobj, &fadump_attr.attr);
 	if (rc)
 		printk(KERN_ERR "fadump: unable to create sysfs file"
@@ -1458,6 +1476,26 @@ static void fadump_init_files(void)
 			printk(KERN_ERR "fadump: unable to create sysfs file"
 				" fadump_release_mem (%d)\n", rc);
 	}
+	/* Replicating the following sysfs attributes under FADump kobject.
+	 *
+	 *	- fadump_enabled -> enabled
+	 *	- fadump_registered -> registered
+	 *	- fadump_release_mem -> release_mem
+	 */
+	rc = sysfs_create_file(fadump_kobj, &enable_attr.attr);
+	if (rc)
+		pr_err("unable to create enabled sysfs file (%d)\n",
+		       rc);
+	rc = sysfs_create_file(fadump_kobj, &register_attr.attr);
+	if (rc)
+		pr_err("unable to create registered sysfs file (%d)\n",
+		       rc);
+	if (fw_dump.dump_active) {
+		rc = sysfs_create_file(fadump_kobj, &release_attr.attr);
+		if (rc)
+			pr_err("unable to create release_mem sysfs file (%d)\n",
+			       rc);
+	}
 	return;
 }
 
diff --git a/arch/powerpc/platforms/powernv/opal-core.c b/arch/powerpc/platforms/powernv/opal-core.c
index ed895d82c048..b001e2242909 100644
--- a/arch/powerpc/platforms/powernv/opal-core.c
+++ b/arch/powerpc/platforms/powernv/opal-core.c
@@ -589,7 +589,7 @@ static ssize_t fadump_release_opalcore_store(struct kobject *kobj,
 	return count;
 }
 
-static struct kobj_attribute opalcore_rel_attr = __ATTR(fadump_release_opalcore,
+static struct kobj_attribute opalcore_rel_attr = __ATTR(release_opalcore,
 						0200, NULL,
 						fadump_release_opalcore_store);
 
@@ -625,9 +625,13 @@ static int __init opalcore_init(void)
 		return rc;
 	}
 
-	rc = sysfs_create_file(kernel_kobj, &opalcore_rel_attr.attr);
+	/*
+	 * Originally fadump_release_opalcore sysfs was part of kernel_kobj
+	 * later moved to fadump_kobj and renamed to release_opalcore.
+	 */
+	rc = sysfs_create_file(fadump_kobj, &opalcore_rel_attr.attr);
 	if (rc) {
-		pr_warn("unable to create sysfs file fadump_release_opalcore (%d)\n",
+		pr_warn("unable to create sysfs file release_opalcore (%d)\n",
 			rc);
 	}
 
-- 
2.17.2


  parent reply index

Thread overview: 11+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-11-09 12:23 [PATCH v3 0/4] reorganize and add FADump " Sourabh Jain
2019-11-09 12:23 ` [PATCH v3 1/4] Documentation/ABI: add ABI documentation for /sys/kernel/fadump_* Sourabh Jain
2019-11-09 12:23 ` Sourabh Jain [this message]
2019-11-09 12:59   ` [PATCH v3 2/4] powerpc/fadump: reorganize /sys/kernel/fadump_* sysfs files Michal Suchánek
2019-11-16 14:37     ` Sourabh Jain
2019-11-24 18:40       ` Michal Suchánek
2019-11-27  4:54         ` Sourabh Jain
2019-12-03 11:20         ` Sourabh Jain
2019-11-23 11:21   ` kbuild test robot
2019-11-09 12:23 ` [PATCH v3 3/4] Documentation/ABI: mark /sys/kernel/fadump_* sysfs files deprecated Sourabh Jain
2019-11-09 12:23 ` [PATCH v3 4/4] powerpc/fadump: sysfs for fadump memory reservation Sourabh Jain

Reply instructions:

You may reply publically to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20191109122339.20484-3-sourabhjain@linux.ibm.com \
    --to=sourabhjain@linux.ibm.com \
    --cc=corbet@lwn.net \
    --cc=hbathini@linux.ibm.com \
    --cc=linux-doc@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linuxppc-dev@ozlabs.org \
    --cc=mahesh@linux.vnet.ibm.com \
    --cc=mpe@ellerman.id.au \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

LinuxPPC-Dev Archive on lore.kernel.org

Archives are clonable:
	git clone --mirror https://lore.kernel.org/linuxppc-dev/0 linuxppc-dev/git/0.git

	# If you have public-inbox 1.1+ installed, you may
	# initialize and index your mirror using the following commands:
	public-inbox-init -V2 linuxppc-dev linuxppc-dev/ https://lore.kernel.org/linuxppc-dev \
		linuxppc-dev@lists.ozlabs.org linuxppc-dev@ozlabs.org
	public-inbox-index linuxppc-dev

Example config snippet for mirrors

Newsgroup available over NNTP:
	nntp://nntp.lore.kernel.org/org.ozlabs.lists.linuxppc-dev


AGPL code for this site: git clone https://public-inbox.org/public-inbox.git