From: Vishal Verma <vishal.l.verma@intel.com>
To: Dan Williams <dan.j.williams@intel.com>,
Vishal Verma <vishal.l.verma@intel.com>,
Dave Jiang <dave.jiang@intel.com>,
Andrew Morton <akpm@linux-foundation.org>,
Oscar Salvador <osalvador@suse.de>
Cc: linux-kernel@vger.kernel.org, nvdimm@lists.linux.dev,
linux-cxl@vger.kernel.org, David Hildenbrand <david@redhat.com>,
Dave Hansen <dave.hansen@linux.intel.com>,
Huang Ying <ying.huang@intel.com>,
Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
linux-mm@kvack.org
Subject: [PATCH v5 1/4] Documentatiion/ABI: Add ABI documentation for sys-bus-dax
Date: Thu, 14 Dec 2023 00:37:54 -0700 [thread overview]
Message-ID: <20231214-vv-dax_abi-v5-1-3f7b006960b4@intel.com> (raw)
In-Reply-To: <20231214-vv-dax_abi-v5-0-3f7b006960b4@intel.com>
Add the missing sysfs ABI documentation for the device DAX subsystem.
Various ABI attributes under this have been present since v5.1, and more
have been added over time. In preparation for adding a new attribute,
add this file with the historical details.
Cc: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>
---
Documentation/ABI/testing/sysfs-bus-dax | 136 ++++++++++++++++++++++++++++++++
1 file changed, 136 insertions(+)
diff --git a/Documentation/ABI/testing/sysfs-bus-dax b/Documentation/ABI/testing/sysfs-bus-dax
new file mode 100644
index 000000000000..6359f7bc9bf4
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-bus-dax
@@ -0,0 +1,136 @@
+What: /sys/bus/dax/devices/daxX.Y/align
+Date: October, 2020
+KernelVersion: v5.10
+Contact: nvdimm@lists.linux.dev
+Description:
+ (RW) Provides a way to specify an alignment for a dax device.
+ Values allowed are constrained by the physical address ranges
+ that back the dax device, and also by arch requirements.
+
+What: /sys/bus/dax/devices/daxX.Y/mapping
+Date: October, 2020
+KernelVersion: v5.10
+Contact: nvdimm@lists.linux.dev
+Description:
+ (WO) Provides a way to allocate a mapping range under a dax
+ device. Specified in the format <start>-<end>.
+
+What: /sys/bus/dax/devices/daxX.Y/mapping[0..N]/start
+What: /sys/bus/dax/devices/daxX.Y/mapping[0..N]/end
+What: /sys/bus/dax/devices/daxX.Y/mapping[0..N]/page_offset
+Date: October, 2020
+KernelVersion: v5.10
+Contact: nvdimm@lists.linux.dev
+Description:
+ (RO) A dax device may have multiple constituent discontiguous
+ address ranges. These are represented by the different
+ 'mappingX' subdirectories. The 'start' attribute indicates the
+ start physical address for the given range. The 'end' attribute
+ indicates the end physical address for the given range. The
+ 'page_offset' attribute indicates the offset of the current
+ range in the dax device.
+
+What: /sys/bus/dax/devices/daxX.Y/resource
+Date: June, 2019
+KernelVersion: v5.3
+Contact: nvdimm@lists.linux.dev
+Description:
+ (RO) The resource attribute indicates the starting physical
+ address of a dax device. In case of a device with multiple
+ constituent ranges, it indicates the starting address of the
+ first range.
+
+What: /sys/bus/dax/devices/daxX.Y/size
+Date: October, 2020
+KernelVersion: v5.10
+Contact: nvdimm@lists.linux.dev
+Description:
+ (RW) The size attribute indicates the total size of a dax
+ device. For creating subdivided dax devices, or for resizing
+ an existing device, the new size can be written to this as
+ part of the reconfiguration process.
+
+What: /sys/bus/dax/devices/daxX.Y/numa_node
+Date: November, 2019
+KernelVersion: v5.5
+Contact: nvdimm@lists.linux.dev
+Description:
+ (RO) If NUMA is enabled and the platform has affinitized the
+ backing device for this dax device, emit the CPU node
+ affinity for this device.
+
+What: /sys/bus/dax/devices/daxX.Y/target_node
+Date: February, 2019
+KernelVersion: v5.1
+Contact: nvdimm@lists.linux.dev
+Description:
+ (RO) The target-node attribute is the Linux numa-node that a
+ device-dax instance may create when it is online. Prior to
+ being online the device's 'numa_node' property reflects the
+ closest online cpu node which is the typical expectation of a
+ device 'numa_node'. Once it is online it becomes its own
+ distinct numa node.
+
+What: $(readlink -f /sys/bus/dax/devices/daxX.Y)/../dax_region/available_size
+Date: October, 2020
+KernelVersion: v5.10
+Contact: nvdimm@lists.linux.dev
+Description:
+ (RO) The available_size attribute tracks available dax region
+ capacity. This only applies to volatile hmem devices, not pmem
+ devices, since pmem devices are defined by nvdimm namespace
+ boundaries.
+
+What: $(readlink -f /sys/bus/dax/devices/daxX.Y)/../dax_region/size
+Date: July, 2017
+KernelVersion: v5.1
+Contact: nvdimm@lists.linux.dev
+Description:
+ (RO) The size attribute indicates the size of a given dax region
+ in bytes.
+
+What: $(readlink -f /sys/bus/dax/devices/daxX.Y)/../dax_region/align
+Date: October, 2020
+KernelVersion: v5.10
+Contact: nvdimm@lists.linux.dev
+Description:
+ (RO) The align attribute indicates alignment of the dax region.
+ Changes on align may not always be valid, when say certain
+ mappings were created with 2M and then we switch to 1G. This
+ validates all ranges against the new value being attempted, post
+ resizing.
+
+What: $(readlink -f /sys/bus/dax/devices/daxX.Y)/../dax_region/seed
+Date: October, 2020
+KernelVersion: v5.10
+Contact: nvdimm@lists.linux.dev
+Description:
+ (RO) The seed device is a concept for dynamic dax regions to be
+ able to split the region amongst multiple sub-instances. The
+ seed device, similar to libnvdimm seed devices, is a device
+ that starts with zero capacity allocated and unbound to a
+ driver.
+
+What: $(readlink -f /sys/bus/dax/devices/daxX.Y)/../dax_region/create
+Date: October, 2020
+KernelVersion: v5.10
+Contact: nvdimm@lists.linux.dev
+Description:
+ (RW) The create interface to the dax region provides a way to
+ create a new unconfigured dax device under the given region, which
+ can then be configured (with a size etc.) and then probed.
+
+What: $(readlink -f /sys/bus/dax/devices/daxX.Y)/../dax_region/delete
+Date: October, 2020
+KernelVersion: v5.10
+Contact: nvdimm@lists.linux.dev
+Description:
+ (WO) The delete interface for a dax region provides for deletion
+ of any 0-sized and idle dax devices.
+
+What: $(readlink -f /sys/bus/dax/devices/daxX.Y)/../dax_region/id
+Date: July, 2017
+KernelVersion: v5.1
+Contact: nvdimm@lists.linux.dev
+Description:
+ (RO) The id attribute indicates the region id of a dax region.
--
2.41.0
next prev parent reply other threads:[~2023-12-14 7:38 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-12-14 7:37 [PATCH v5 0/4] Add DAX ABI for memmap_on_memory Vishal Verma
2023-12-14 7:37 ` Vishal Verma [this message]
2023-12-14 7:37 ` [PATCH v5 2/4] dax/bus: Use guard(device) in sysfs attribute helpers Vishal Verma
2023-12-14 7:37 ` [PATCH v5 3/4] mm/memory_hotplug: export mhp_supports_memmap_on_memory() Vishal Verma
2023-12-14 9:10 ` David Hildenbrand
2023-12-14 7:37 ` [PATCH v5 4/4] dax: add a sysfs knob to control memmap_on_memory behavior Vishal Verma
2023-12-14 8:31 ` Greg Kroah-Hartman
2023-12-15 4:53 ` Huang, Ying
Reply instructions:
You may reply publicly 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=20231214-vv-dax_abi-v5-1-3f7b006960b4@intel.com \
--to=vishal.l.verma@intel.com \
--cc=akpm@linux-foundation.org \
--cc=dan.j.williams@intel.com \
--cc=dave.hansen@linux.intel.com \
--cc=dave.jiang@intel.com \
--cc=david@redhat.com \
--cc=gregkh@linuxfoundation.org \
--cc=linux-cxl@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=nvdimm@lists.linux.dev \
--cc=osalvador@suse.de \
--cc=ying.huang@intel.com \
/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
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.