* [PATCH V5 00/17] Add CXL LSA 2.1 format support in nvdimm and cxl pmem
[not found] <CGME20260109124454epcas5p4513168fdb4253ef1c5ac1656985417fd@epcas5p4.samsung.com>
@ 2026-01-09 12:44 ` Neeraj Kumar
2026-01-09 12:44 ` [PATCH V5 01/17] nvdimm/label: Introduce NDD_REGION_LABELING flag to set region label Neeraj Kumar
` (17 more replies)
0 siblings, 18 replies; 53+ messages in thread
From: Neeraj Kumar @ 2026-01-09 12:44 UTC (permalink / raw)
To: linux-cxl, nvdimm, linux-kernel, gost.dev
Cc: a.manzanares, vishak.g, neeraj.kernel, Neeraj Kumar
Introduction:
=============
CXL Persistent Memory (Pmem) devices region, namespace and content must be
persistent across system reboot. In order to achieve this persistency, it
uses Label Storage Area (LSA) to store respective metadata. During system
reboot, stored metadata in LSA is used to bring back the region, namespace
and content of CXL device in its previous state.
CXL specification provides Get_LSA (4102h) and Set_LSA (4103h) mailbox
commands to access the LSA area. nvdimm driver is using same commands to
get/set LSA data.
There are three types of LSA format and these are part of following
specifications:
- v1.1: https://pmem.io/documents/NVDIMM_Namespace_Spec.pdf
- v1.2: https://uefi.org/sites/default/files/resources/UEFI_Spec_2_7.pdf
- v2.1: https://computeexpresslink.org/wp-content/uploads/2024/02/CXL-2.0-Specification.pdf
Basic differences between these LSA formats:
- v1.1: Support Namespace persistency. Size of Namespace Label is 128 bytes
- v1.2: Support Namespace persistency. Size of Namespace Label is 256 bytes
- v2.1: Support Namespace and Region persistency. Size of Namespace and
Region Label is 256 bytes.
Linux nvdimm driver supports only v1.1 and v1.2 LSA format. CXL pmem device
require support of LSA v2.1 format for region and namespace persistency.
Initial support of LSA 2.1 was add in [1].
This patchset adds support of LSA 2.1 in nvdimm and cxl pmem driver.
Patch 1: Introduce NDD_CXL_LABEL flag and Update cxl label index as per v2.1
Patch 2: Skip the need for 'interleave-set cookie' for LSA 2.1 support
Patch 3-9: Introduce region label and update namespace label as per LSA 2.1
Patch 10: Refactor cxl pmem region auto assembly using Dan's Infra [2]
Patch 11-12: Save cxl region info in LSA and region recreation during reboot
Patch 13:14: Segregate out cxl pmem region code from region.c to pmem_region.c
Patch 15: Introduce cxl region addition/deletion attributes
Patch 16-17: Add support of cxl pmem region re-creation from CXL as per LSA 2.1
Pre-requisite:
==============
This patch series has dependency on Dan's Infra [2]
Testing:
========
In order to test this patchset, I also added the support of LSA v2.1 format
in ndctl. ndctl changes are available at [3]. After review, I’ll push in
ndctl repo for community review.
1. Used Qemu using following CXL topology
M2="-object memory-backend-file,id=cxl-mem11,share=on,mem-path=$TMP_DIR/cxltest11.raw,size=4G \
-object memory-backend-file,id=cxl-lsa11,share=on,mem-path=$TMP_DIR/lsa.raw11,size=1M \
-object memory-backend-file,id=cxl-mem21,share=on,mem-path=$TMP_DIR/cxltest21.raw,size=4G \
-object memory-backend-file,id=cxl-lsa21,share=on,mem-path=$TMP_DIR/lsa21.raw,size=1M \
-device pxb-cxl,bus=pcie.0,bus_nr=10,id=cxl.1 \
-device cxl-rp,port=110,bus=cxl.1,id=root_port11,chassis=0,slot=11 \
-device cxl-type3,bus=root_port11,memdev=cxl-mem11,lsa=cxl-lsa11,id=cxl-pmem11,sn=11 \
-device pxb-cxl,bus=pcie.0,bus_nr=20,id=cxl.2 \
-device cxl-rp,port=210,bus=cxl.2,id=root_port21,chassis=0,slot=21 \
-device cxl-type3,bus=root_port21,memdev=cxl-mem21,lsa=cxl-lsa21,id=cxl-pmem21,sn=21 \
-M cxl-fmw.0.targets.0=cxl.1,cxl-fmw.0.size=8G,cxl-fmw.0.interleave-granularity=8k,cxl-fmw.1.targets.0=cxl.2,cxl-fmw.1.size=8G"
2. Create cxl region on both devices
cxl create-region -d decoder0.1 -m mem0
cxl create-region -d decoder0.0 -m mem1
root@QEMUCXL6060pmem:~# cxl list
[
{
"memdevs":[
{
"memdev":"mem0",
"pmem_size":4294967296,
"serial":21,
"host":"0000:15:00.0",
"firmware_version":"BWFW VERSION 00"
},
{
"memdev":"mem1",
"pmem_size":4294967296,
"serial":11,
"host":"0000:0b:00.0",
"firmware_version":"BWFW VERSION 00"
}
]
},
{
"regions":[
{
"region":"region0",
"resource":45365592064,
"size":4294967296,
"type":"pmem",
"interleave_ways":1,
"interleave_granularity":256,
"decode_state":"commit",
"qos_class_mismatch":true
},
{
"region":"region1",
"resource":53955526656,
"size":4294967296,
"type":"pmem",
"interleave_ways":1,
"interleave_granularity":256,
"decode_state":"commit",
"qos_class_mismatch":true
}
]
}
]
3. Re-Start Qemu and we could see cxl region persistency using "cxl list"
4. Create namespace for both regions
root@QEMUCXL6060pmem:~# time ndctl create-namespace --mode=fsdax --region=region0 --size=256M
{
"dev":"namespace0.1",
"mode":"fsdax",
"map":"dev",
"size":"250.00 MiB (262.14 MB)",
"uuid":"5f9e28b4-f403-4e72-bb06-307ead53dec4",
"sector_size":512,
"align":2097152,
"blockdev":"pmem0.1"
}
real 1m8.795s
user 0m0.098s
sys 0m48.699s
root@QEMUCXL6060pmem:~# time ndctl create-namespace --mode=fsdax --region=region1 --size=128M
{
"dev":"namespace1.1",
"mode":"fsdax",
"map":"dev",
"size":"124.00 MiB (130.02 MB)",
"uuid":"33682096-7364-412d-bfbc-fa7568939abd",
"sector_size":512,
"align":2097152,
"blockdev":"pmem1.1"
}
root@QEMUCXL6060pmem:~# time ndctl create-namespace --mode=fsdax --region=region0 --size=128M
{
"dev":"namespace0.0",
"mode":"fsdax",
"map":"dev",
"size":"124.00 MiB (130.02 MB)",
"uuid":"9681af0e-349a-401e-9833-1cf8903d58fa",
"sector_size":512,
"align":2097152,
"blockdev":"pmem0"
}
real 0m39.805s
user 0m0.138s
sys 0m21.485s
root@QEMUCXL6060pmem:~# time ndctl create-namespace --mode=fsdax --region=region1 --size=256M
{
"dev":"namespace1.0",
"mode":"fsdax",
"map":"dev",
"size":"250.00 MiB (262.14 MB)",
"uuid":"15f1c8d5-416f-4d2e-9e39-d17ce8f73a42",
"sector_size":512,
"align":2097152,
"blockdev":"pmem1"
}
real 0m43.899s
user 0m0.113s
sys 0m31.167s
root@QEMUCXL6060pmem:~# time ndctl create-namespace --mode=fsdax --region=region0 --size=128M
{
"dev":"namespace0.0",
"mode":"fsdax",
"map":"dev",
"size":"124.00 MiB (130.02 MB)",
"uuid":"9681af0e-349a-401e-9833-1cf8903d58fa",
"sector_size":512,
"align":2097152,
"blockdev":"pmem0"
}
real 0m39.805s
user 0m0.138s
sys 0m21.485s
root@QEMUCXL6060pmem:~# ndctl list
[
{
"dev":"namespace1.0",
"mode":"fsdax",
"map":"dev",
"size":262144000,
"uuid":"15f1c8d5-416f-4d2e-9e39-d17ce8f73a42",
"sector_size":512,
"align":2097152,
"blockdev":"pmem1"
},
{
"dev":"namespace1.1",
"mode":"fsdax",
"map":"dev",
"size":130023424,
"uuid":"33682096-7364-412d-bfbc-fa7568939abd",
"sector_size":512,
"align":2097152,
"blockdev":"pmem1.1"
},
{
"dev":"namespace0.1",
"mode":"fsdax",
"map":"dev",
"size":262144000,
"uuid":"5f9e28b4-f403-4e72-bb06-307ead53dec4",
"sector_size":512,
"align":2097152,
"blockdev":"pmem0.1"
},
{
"dev":"namespace0.0",
"mode":"fsdax",
"map":"dev",
"size":130023424,
"uuid":"9681af0e-349a-401e-9833-1cf8903d58fa",
"sector_size":512,
"align":2097152,
"blockdev":"pmem0"
}
]
5. Re-Start Qemu and we could see
- Region persistency using "cxl list"
- Namespace persistency using "ndctl list" and cat /proc/iomem
root@QEMUCXL6060pmem:~# cat /proc/iomem
fed1c000-fed1ffff : Reserved
feffc000-feffffff : Reserved
fffc0000-ffffffff : Reserved
100000000-27fffffff : System RAM
a90000000-c8fffffff : CXL Window 0
a90000000-b8fffffff : Persistent Memory
a90000000-b8fffffff : region0
a90000000-a97ffffff : namespace0.0
a98000000-aa7ffffff : namespace0.1
c90000000-e8fffffff : CXL Window 1
c90000000-d8fffffff : Persistent Memory
c90000000-d8fffffff : region1
c90000000-c9fffffff : namespace1.0
ca0000000-ca7ffffff : namespace1.1
380000000000-38000000ffff : PCI Bus 0000:0a
380000000000-38000000ffff : 0000:0a:00.0
- NOTE: We can see some lag in restart. Look at Observesation below
6. Also verify LSA version using "ndctl read-labels -j nmem0"
root@QEMUCXL6060pmem:~# time ndctl read-labels -j nmem0
{
"dev":"nmem0",
"index":[
{
"signature":"NAMESPACE_INDEX",
"major":2,
"minor":1,
"labelsize":256,
"seq":2,
"nslot":4090
},
{
"signature":"NAMESPACE_INDEX",
"major":2,
"minor":1,
"labelsize":256,
"seq":1,
"nslot":4090
}
],
"label":[
{
"type":"68bb2c0a-5a77-4937-9f85-3caf41a0f93c",
"uuid":"5b33b940-6767-4951-b923-952455482f52",
"name":"",
"flags":8,
"nrange":1,
"position":0,
"dpa":134217728,
"rawsize":268435456,
"slot":0,
"align":0,
"region_uuid":"a1482e6b-968e-4297-b2f5-bf1733966e55",
"abstraction_uuid":"266400ba-fb9f-4677-bcb0-968f11d0d225",
"lbasize":512
},
{
"type":"529d7c61-da07-47c4-a93f-ecdf2c06f444",
"uuid":"a1482e6b-968e-4297-b2f5-bf1733966e55",
"flags":0,
"nlabel":1,
"position":0,
"dpa":0,
"rawsize":4294967296,
"hpa":45365592064,
"slot":1,
"interleave granularity":256,
"align":0
},
{
"type":"68bb2c0a-5a77-4937-9f85-3caf41a0f93c",
"uuid":"2c1c33c0-909b-4c6a-8de4-dfc6c13ae82c",
"name":"",
"flags":0,
"nrange":1,
"position":0,
"dpa":0,
"rawsize":134217728,
"slot":2,
"align":0,
"region_uuid":"a1482e6b-968e-4297-b2f5-bf1733966e55",
"abstraction_uuid":"266400ba-fb9f-4677-bcb0-968f11d0d225",
"lbasize":512
},
{
"type":"68bb2c0a-5a77-4937-9f85-3caf41a0f93c",
"uuid":"5b33b940-6767-4951-b923-952455482f52",
"name":"",
"flags":0,
"nrange":1,
"position":0,
"dpa":134217728,
"rawsize":268435456,
"slot":3,
"align":0,
"region_uuid":"a1482e6b-968e-4297-b2f5-bf1733966e55",
"abstraction_uuid":"266400ba-fb9f-4677-bcb0-968f11d0d225",
"lbasize":512
}
]
}
read 1 nmem
- NOTE: We have following UUID types as per CXL Spec
"type":"529d7c61-da07-47c4-a93f-ecdf2c06f444" is region label
"type":"68bb2c0a-5a77-4937-9f85-3caf41a0f93c" is namespace label
Limitation (WIP):
================
Current changes only support interleave way == 1
Observation:
============
First time namespace creation using ndctl takes around 10 to 20 second time
while executing "devm_memremap_pages" at [4]
As using this patchset, after auto region creation, namespace creation is
happening in boot sequence (if nvdimm and cxl drivers are static), It is
therefore boot sequence is increased by around 10 to 20 sec.
Changes
=======
Changes in v4->v5
-----------------
- Find v4 link at [5]
- Find v3 link at [6]
- Find v2 link at [7]
- v1 patch-set was broken. Find the v1 links at [8] and [9]
[PATCH 03/17]
- Remove extra space after typecasting [Dave]
- Fix inconsistent tabbing [Dave]
- Fix initialization of region_label_cnt [Jonathan]
- Use guard(nvdimm_bus) in place of nvdimm_bus_lock() [Jonathan]
- Use export_uuid() instead of uuid_copy() [Jonathan]
- Remove extra varible from is_region_label() [Jonathan]
- Remove extra region label setter functions [Jonathan]
[PATCH 04/17]
- Add Dave RB tag
[PATCH 05/17]
- Add Dave RB tag
- Elaborate Commit message [Jonathan]
[PATCH 06/17]
- Add Dave RB tag
[PATCH 07/17]
- Add Dave RB tag
- Add Jonathan RB tag
- Use guard(nvdimm_bus) in place of nvdimm_bus_lock() [Dave]
- Fix alignment to improve readability [Jonathan]
- Remove extra nd_mapping variable [Jonathan]
[PATCH 08/17]
- Add Dave RB tag
- Fix alignment to improve readability [Jonathan]
[PATCH 09/17]
- Add Dave RB tag
- Remove extra nvdimm NULL check [Jonathan]
[PATCH 10/17]
- Add Dave RB tag
- Fix spelling mistake [Dave]
[PATCH 11/17]
- Add Dave RB tag
- Reorder size NULL check [Dave]
- Fix device reference underflow in error case [Jonathan]
[PATCH 12/17]
- Add Dave RB tag
[PATCH 13/17]
- Add Dave RB tag
- Reword Commit message [Jonathan]
- Drop trailing comma [Jonathan]
[PATCH 14/17]
- Add Dave RB tag
- Fix Config condition check and move return in stub routine [Jonathan]
[PATCH 15/17]
- Reword region_label_update documentation [Dave]
- Fix coding style in region_label_update_store() [Jonathan]
[PATCH 16/17]
- Reword commit message [Dave]
- Fix verify_free_decoder() return handling [Dave]
- Fix match_root_decoder() using ep_port->host_bridge dport
instead of match_first_root_decoder [Dave]
[PATCH 14/17]
- Add Dave RB tag
[1]: https://lore.kernel.org/all/163116432405.2460985.5547867384570123403.stgit@dwillia2-desk3.amr.corp.intel.com/
[2]: https://git.kernel.org/pub/scm/linux/kernel/git/cxl/cxl.git/patch/?id=ab70c6227ee6165a562c215d9dcb4a1c55620d5d
[3]: https://github.com/neerajoss/ndctl/commits/linux-cxl/V1_CXL_LSA_2.1_Support/
[4]: https://elixir.bootlin.com/linux/v6.13.7/source/drivers/nvdimm/pmem.c#L520
[5]: https://lore.kernel.org/linux-cxl/20250917134116.1623730-1-s.neeraj@samsung.com/
[6]: https://lore.kernel.org/linux-cxl/20251119075255.2637388-1-s.neeraj@samsung.com/
[7]: https://lore.kernel.org/linux-cxl/20250730121209.303202-1-s.neeraj@samsung.com/
[8] v1 Cover Letter: https://lore.kernel.org/linux-cxl/1931444790.41750165203442.JavaMail.epsvc@epcpadp1new/
[9] v1 Rest Thread: https://lore.kernel.org/linux-cxl/158453976.61750165203630.JavaMail.epsvc@epcpadp1new/
Neeraj Kumar (17):
nvdimm/label: Introduce NDD_REGION_LABELING flag to set region label
nvdimm/label: CXL labels skip the need for 'interleave-set cookie'
nvdimm/label: Add namespace/region label support as per LSA 2.1
nvdimm/label: Include region label in slot validation
nvdimm/label: Skip region label during ns label DPA reservation
nvdimm/label: Preserve region label during namespace creation
nvdimm/label: Add region label delete support
nvdimm/label: Preserve cxl region information from region label
nvdimm/label: Export routine to fetch region information
cxl/mem: Refactor cxl pmem region auto-assembling
cxl/region: Add devm_cxl_pmem_add_region() for pmem region creation
cxl/pmem: Preserve region information into nd_set
cxl/pmem_region: Prep patch to accommodate pmem_region attributes
cxl/pmem_region: Introduce CONFIG_CXL_PMEM_REGION for core/pmem_region.c
cxl/pmem_region: Add sysfs attribute cxl region label updation/deletion
cxl/pmem_region: Create pmem region using information parsed from LSA
cxl/pmem: Add CXL LSA 2.1 support in cxl pmem
Documentation/ABI/testing/sysfs-bus-cxl | 22 +
drivers/cxl/Kconfig | 15 +
drivers/cxl/core/Makefile | 1 +
drivers/cxl/core/core.h | 35 +-
drivers/cxl/core/pmem_region.c | 425 +++++++++++++++++
drivers/cxl/core/region.c | 383 ++++++++--------
drivers/cxl/cxl.h | 41 +-
drivers/cxl/mem.c | 18 +-
drivers/cxl/pci.c | 4 +-
drivers/cxl/pmem.c | 15 +-
drivers/cxl/port.c | 39 +-
drivers/nvdimm/dimm.c | 5 +
drivers/nvdimm/dimm_devs.c | 19 +
drivers/nvdimm/label.c | 579 ++++++++++++++++++++----
drivers/nvdimm/label.h | 18 +-
drivers/nvdimm/namespace_devs.c | 82 +++-
drivers/nvdimm/nd-core.h | 2 +
drivers/nvdimm/nd.h | 59 +++
drivers/nvdimm/region_devs.c | 10 +
include/linux/libnvdimm.h | 28 ++
tools/testing/cxl/Kbuild | 1 +
21 files changed, 1426 insertions(+), 375 deletions(-)
create mode 100644 drivers/cxl/core/pmem_region.c
base-commit: fa19611f96fd8573c826d61a1e9410938a581bf3
prerequisite-patch-id: f6e07504b17ccf39d9486352b6f7305a03897863
prerequisite-patch-id: cd6bad0c8b993bb59369941905f418f3b799c89d
prerequisite-patch-id: 08ebdae0888c0a2631c3b26990679a0261f34f14
prerequisite-patch-id: 344220faa9c156afec0f5d866ad3098880a85e34
--
2.34.1
^ permalink raw reply [flat|nested] 53+ messages in thread
* [PATCH V5 01/17] nvdimm/label: Introduce NDD_REGION_LABELING flag to set region label
2026-01-09 12:44 ` [PATCH V5 00/17] Add CXL LSA 2.1 format support in nvdimm and cxl pmem Neeraj Kumar
@ 2026-01-09 12:44 ` Neeraj Kumar
2026-01-14 21:22 ` Ira Weiny
2026-01-09 12:44 ` [PATCH V5 02/17] nvdimm/label: CXL labels skip the need for 'interleave-set cookie' Neeraj Kumar
` (16 subsequent siblings)
17 siblings, 1 reply; 53+ messages in thread
From: Neeraj Kumar @ 2026-01-09 12:44 UTC (permalink / raw)
To: linux-cxl, nvdimm, linux-kernel, gost.dev
Cc: a.manzanares, vishak.g, neeraj.kernel, Neeraj Kumar
Prior to LSA 2.1 version, LSA contain only namespace labels. LSA 2.1
introduced in CXL 2.0 Spec, which contain region label along with
namespace label.
NDD_LABELING flag is used for namespace. Introduced NDD_REGION_LABELING
flag for region label. Based on these flags nvdimm driver performs
operation on namespace label or region label.
NDD_REGION_LABELING will be utilized by cxl driver to enable LSA 2.1
region label support
Accordingly updated label index version
Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Neeraj Kumar <s.neeraj@samsung.com>
---
drivers/nvdimm/dimm.c | 1 +
drivers/nvdimm/dimm_devs.c | 7 +++++++
drivers/nvdimm/label.c | 21 +++++++++++++++++----
drivers/nvdimm/nd.h | 1 +
include/linux/libnvdimm.h | 3 +++
5 files changed, 29 insertions(+), 4 deletions(-)
diff --git a/drivers/nvdimm/dimm.c b/drivers/nvdimm/dimm.c
index 2f6c26cc6a3e..07f5c5d5e537 100644
--- a/drivers/nvdimm/dimm.c
+++ b/drivers/nvdimm/dimm.c
@@ -62,6 +62,7 @@ static int nvdimm_probe(struct device *dev)
if (rc < 0)
dev_dbg(dev, "failed to unlock dimm: %d\n", rc);
+ ndd->cxl = nvdimm_region_label_supported(ndd->dev);
/*
* EACCES failures reading the namespace label-area-properties
diff --git a/drivers/nvdimm/dimm_devs.c b/drivers/nvdimm/dimm_devs.c
index e1349ef5f8fd..3363a97cc5b5 100644
--- a/drivers/nvdimm/dimm_devs.c
+++ b/drivers/nvdimm/dimm_devs.c
@@ -18,6 +18,13 @@
static DEFINE_IDA(dimm_ida);
+bool nvdimm_region_label_supported(struct device *dev)
+{
+ struct nvdimm *nvdimm = to_nvdimm(dev);
+
+ return test_bit(NDD_REGION_LABELING, &nvdimm->flags);
+}
+
/*
* Retrieve bus and dimm handle and return if this bus supports
* get_config_data commands
diff --git a/drivers/nvdimm/label.c b/drivers/nvdimm/label.c
index 04f4a049599a..0a9b6c5cb2c3 100644
--- a/drivers/nvdimm/label.c
+++ b/drivers/nvdimm/label.c
@@ -688,11 +688,24 @@ static int nd_label_write_index(struct nvdimm_drvdata *ndd, int index, u32 seq,
- (unsigned long) to_namespace_index(ndd, 0);
nsindex->labeloff = __cpu_to_le64(offset);
nsindex->nslot = __cpu_to_le32(nslot);
- nsindex->major = __cpu_to_le16(1);
- if (sizeof_namespace_label(ndd) < 256)
+
+ /* Set LSA Label Index Version */
+ if (ndd->cxl) {
+ /* CXL r3.2: Table 9-9 Label Index Block Layout */
+ nsindex->major = __cpu_to_le16(2);
nsindex->minor = __cpu_to_le16(1);
- else
- nsindex->minor = __cpu_to_le16(2);
+ } else {
+ nsindex->major = __cpu_to_le16(1);
+ /*
+ * NVDIMM Namespace Specification
+ * Table 2: Namespace Label Index Block Fields
+ */
+ if (sizeof_namespace_label(ndd) < 256)
+ nsindex->minor = __cpu_to_le16(1);
+ else /* UEFI 2.7: Label Index Block Definitions */
+ nsindex->minor = __cpu_to_le16(2);
+ }
+
nsindex->checksum = __cpu_to_le64(0);
if (flags & ND_NSINDEX_INIT) {
unsigned long *free = (unsigned long *) nsindex->free;
diff --git a/drivers/nvdimm/nd.h b/drivers/nvdimm/nd.h
index b199eea3260e..f631bd84d6f0 100644
--- a/drivers/nvdimm/nd.h
+++ b/drivers/nvdimm/nd.h
@@ -522,6 +522,7 @@ void nvdimm_set_labeling(struct device *dev);
void nvdimm_set_locked(struct device *dev);
void nvdimm_clear_locked(struct device *dev);
int nvdimm_security_setup_events(struct device *dev);
+bool nvdimm_region_label_supported(struct device *dev);
#if IS_ENABLED(CONFIG_NVDIMM_KEYS)
int nvdimm_security_unlock(struct device *dev);
#else
diff --git a/include/linux/libnvdimm.h b/include/linux/libnvdimm.h
index 28f086c4a187..5696715c33bb 100644
--- a/include/linux/libnvdimm.h
+++ b/include/linux/libnvdimm.h
@@ -44,6 +44,9 @@ enum {
/* dimm provider wants synchronous registration by __nvdimm_create() */
NDD_REGISTER_SYNC = 8,
+ /* dimm supports region labels (LSA Format 2.1) */
+ NDD_REGION_LABELING = 9,
+
/* need to set a limit somewhere, but yes, this is likely overkill */
ND_IOCTL_MAX_BUFLEN = SZ_4M,
ND_CMD_MAX_ELEM = 5,
--
2.34.1
^ permalink raw reply related [flat|nested] 53+ messages in thread
* [PATCH V5 02/17] nvdimm/label: CXL labels skip the need for 'interleave-set cookie'
2026-01-09 12:44 ` [PATCH V5 00/17] Add CXL LSA 2.1 format support in nvdimm and cxl pmem Neeraj Kumar
2026-01-09 12:44 ` [PATCH V5 01/17] nvdimm/label: Introduce NDD_REGION_LABELING flag to set region label Neeraj Kumar
@ 2026-01-09 12:44 ` Neeraj Kumar
2026-01-09 12:44 ` [PATCH V5 03/17] nvdimm/label: Add namespace/region label support as per LSA 2.1 Neeraj Kumar
` (15 subsequent siblings)
17 siblings, 0 replies; 53+ messages in thread
From: Neeraj Kumar @ 2026-01-09 12:44 UTC (permalink / raw)
To: linux-cxl, nvdimm, linux-kernel, gost.dev
Cc: a.manzanares, vishak.g, neeraj.kernel, Neeraj Kumar
CXL LSA v2.1 utilizes the region labels stored in the LSA for interleave
set configuration instead of interleave-set cookie used in previous LSA
versions. As interleave-set cookie is not required for CXL LSA v2.1 format
so skip its usage for CXL LSA 2.1 format
Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>
Acked-by: Ira Weiny <ira.weiny@intel.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Neeraj Kumar <s.neeraj@samsung.com>
---
drivers/nvdimm/namespace_devs.c | 8 +++++++-
drivers/nvdimm/region_devs.c | 10 ++++++++++
2 files changed, 17 insertions(+), 1 deletion(-)
diff --git a/drivers/nvdimm/namespace_devs.c b/drivers/nvdimm/namespace_devs.c
index a5edcacfe46d..43fdb806532e 100644
--- a/drivers/nvdimm/namespace_devs.c
+++ b/drivers/nvdimm/namespace_devs.c
@@ -1678,7 +1678,13 @@ static struct device *create_namespace_pmem(struct nd_region *nd_region,
int rc = 0;
u16 i;
- if (cookie == 0) {
+ /*
+ * CXL LSA v2.1 utilizes the region label stored in the LSA for
+ * interleave set configuration. Whereas EFI LSA v1.1 & v1.2
+ * utilizes interleave-set cookie. i.e, CXL labels skip the
+ * need for 'interleave-set cookie'
+ */
+ if (!ndd->cxl && cookie == 0) {
dev_dbg(&nd_region->dev, "invalid interleave-set-cookie\n");
return ERR_PTR(-ENXIO);
}
diff --git a/drivers/nvdimm/region_devs.c b/drivers/nvdimm/region_devs.c
index 1220530a23b6..77f36a585f13 100644
--- a/drivers/nvdimm/region_devs.c
+++ b/drivers/nvdimm/region_devs.c
@@ -841,6 +841,16 @@ u64 nd_region_interleave_set_cookie(struct nd_region *nd_region,
if (!nd_set)
return 0;
+ /*
+ * CXL LSA v2.1 utilizes the region label stored in the LSA for
+ * interleave set configuration. Whereas EFI LSA v1.1 & v1.2
+ * utilizes interleave-set cookie. i.e, CXL labels skip the
+ * need for 'interleave-set cookie'
+ */
+ if (nsindex && __le16_to_cpu(nsindex->major) == 2
+ && __le16_to_cpu(nsindex->minor) == 1)
+ return 0;
+
if (nsindex && __le16_to_cpu(nsindex->major) == 1
&& __le16_to_cpu(nsindex->minor) == 1)
return nd_set->cookie1;
--
2.34.1
^ permalink raw reply related [flat|nested] 53+ messages in thread
* [PATCH V5 03/17] nvdimm/label: Add namespace/region label support as per LSA 2.1
2026-01-09 12:44 ` [PATCH V5 00/17] Add CXL LSA 2.1 format support in nvdimm and cxl pmem Neeraj Kumar
2026-01-09 12:44 ` [PATCH V5 01/17] nvdimm/label: Introduce NDD_REGION_LABELING flag to set region label Neeraj Kumar
2026-01-09 12:44 ` [PATCH V5 02/17] nvdimm/label: CXL labels skip the need for 'interleave-set cookie' Neeraj Kumar
@ 2026-01-09 12:44 ` Neeraj Kumar
2026-01-15 17:45 ` Jonathan Cameron
2026-01-21 0:35 ` Ira Weiny
2026-01-09 12:44 ` [PATCH V5 04/17] nvdimm/label: Include region label in slot validation Neeraj Kumar
` (14 subsequent siblings)
17 siblings, 2 replies; 53+ messages in thread
From: Neeraj Kumar @ 2026-01-09 12:44 UTC (permalink / raw)
To: linux-cxl, nvdimm, linux-kernel, gost.dev
Cc: a.manzanares, vishak.g, neeraj.kernel, Neeraj Kumar
Modify __pmem_label_update() to update region labels into LSA
CXL 3.2 Spec mentions CXL LSA 2.1 Namespace Labels at section 9.13.2.5
Modified __pmem_label_update() using setter functions to update
namespace label as per CXL LSA 2.1
Create export routine nd_region_label_update() used for creating
region label into LSA. It will be used later from CXL subsystem
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Neeraj Kumar <s.neeraj@samsung.com>
---
drivers/nvdimm/label.c | 360 ++++++++++++++++++++++++++------
drivers/nvdimm/label.h | 17 +-
drivers/nvdimm/namespace_devs.c | 20 +-
drivers/nvdimm/nd.h | 51 +++++
include/linux/libnvdimm.h | 8 +
5 files changed, 386 insertions(+), 70 deletions(-)
diff --git a/drivers/nvdimm/label.c b/drivers/nvdimm/label.c
index 0a9b6c5cb2c3..17e2a1f5a6da 100644
--- a/drivers/nvdimm/label.c
+++ b/drivers/nvdimm/label.c
@@ -22,8 +22,8 @@ static uuid_t nvdimm_btt2_uuid;
static uuid_t nvdimm_pfn_uuid;
static uuid_t nvdimm_dax_uuid;
-static uuid_t cxl_region_uuid;
-static uuid_t cxl_namespace_uuid;
+uuid_t cxl_region_uuid;
+uuid_t cxl_namespace_uuid;
static const char NSINDEX_SIGNATURE[] = "NAMESPACE_INDEX\0";
@@ -278,15 +278,38 @@ static struct nd_namespace_label *nd_label_base(struct nvdimm_drvdata *ndd)
return base + 2 * sizeof_namespace_index(ndd);
}
+static unsigned long find_slot(struct nvdimm_drvdata *ndd,
+ unsigned long label)
+{
+ unsigned long base;
+
+ base = (unsigned long)nd_label_base(ndd);
+ return (label - base) / sizeof_namespace_label(ndd);
+}
+
+static int to_lsa_slot(struct nvdimm_drvdata *ndd,
+ union nd_lsa_label *lsa_label)
+{
+ return find_slot(ndd, (unsigned long) lsa_label);
+}
+
static int to_slot(struct nvdimm_drvdata *ndd,
- struct nd_namespace_label *nd_label)
+ struct nd_label_ent *label_ent)
+{
+ if (uuid_equal(&cxl_region_uuid, &label_ent->label_uuid))
+ return find_slot(ndd, (unsigned long) label_ent->region_label);
+ else
+ return find_slot(ndd, (unsigned long) label_ent->label);
+}
+
+static union nd_lsa_label *to_lsa_label(struct nvdimm_drvdata *ndd, int slot)
{
unsigned long label, base;
- label = (unsigned long) nd_label;
base = (unsigned long) nd_label_base(ndd);
+ label = base + sizeof_namespace_label(ndd) * slot;
- return (label - base) / sizeof_namespace_label(ndd);
+ return (union nd_lsa_label *) label;
}
static struct nd_namespace_label *to_label(struct nvdimm_drvdata *ndd, int slot)
@@ -381,6 +404,16 @@ static void nsl_calculate_checksum(struct nvdimm_drvdata *ndd,
nsl_set_checksum(ndd, nd_label, sum);
}
+static void region_label_calculate_checksum(struct nvdimm_drvdata *ndd,
+ struct cxl_region_label *region_label)
+{
+ u64 sum;
+
+ region_label->checksum = __cpu_to_le64(0);
+ sum = nd_fletcher64(region_label, sizeof_namespace_label(ndd), 1);
+ region_label->checksum = __cpu_to_le64(sum);
+}
+
static bool slot_valid(struct nvdimm_drvdata *ndd,
struct nd_namespace_label *nd_label, u32 slot)
{
@@ -584,7 +617,7 @@ int nd_label_active_count(struct nvdimm_drvdata *ndd)
return count;
}
-struct nd_namespace_label *nd_label_active(struct nvdimm_drvdata *ndd, int n)
+union nd_lsa_label *nd_label_active(struct nvdimm_drvdata *ndd, int n)
{
struct nd_namespace_index *nsindex;
unsigned long *free;
@@ -601,7 +634,7 @@ struct nd_namespace_label *nd_label_active(struct nvdimm_drvdata *ndd, int n)
continue;
if (n-- == 0)
- return to_label(ndd, slot);
+ return to_lsa_label(ndd, slot);
}
return NULL;
@@ -737,9 +770,9 @@ static int nd_label_write_index(struct nvdimm_drvdata *ndd, int index, u32 seq,
}
static unsigned long nd_label_offset(struct nvdimm_drvdata *ndd,
- struct nd_namespace_label *nd_label)
+ union nd_lsa_label *lsa_label)
{
- return (unsigned long) nd_label
+ return (unsigned long) lsa_label
- (unsigned long) to_namespace_index(ndd, 0);
}
@@ -823,11 +856,15 @@ static void reap_victim(struct nd_mapping *nd_mapping,
struct nd_label_ent *victim)
{
struct nvdimm_drvdata *ndd = to_ndd(nd_mapping);
- u32 slot = to_slot(ndd, victim->label);
+ u32 slot = to_slot(ndd, victim);
dev_dbg(ndd->dev, "free: %d\n", slot);
nd_label_free_slot(ndd, slot);
- victim->label = NULL;
+
+ if (uuid_equal(&cxl_region_uuid, &victim->label_uuid))
+ victim->region_label = NULL;
+ else
+ victim->label = NULL;
}
static void nsl_set_type_guid(struct nvdimm_drvdata *ndd,
@@ -884,26 +921,20 @@ enum nvdimm_claim_class nsl_get_claim_class(struct nvdimm_drvdata *ndd,
return guid_to_nvdimm_cclass(&nd_label->efi.abstraction_guid);
}
-static int __pmem_label_update(struct nd_region *nd_region,
- struct nd_mapping *nd_mapping, struct nd_namespace_pmem *nspm,
- int pos, unsigned long flags)
+static int namespace_label_update(struct nd_region *nd_region,
+ struct nd_mapping *nd_mapping,
+ struct nd_namespace_pmem *nspm,
+ int pos, u64 flags,
+ struct nd_namespace_label *ns_label,
+ struct nd_namespace_index *nsindex,
+ u32 slot)
{
struct nd_namespace_common *ndns = &nspm->nsio.common;
struct nd_interleave_set *nd_set = nd_region->nd_set;
struct nvdimm_drvdata *ndd = to_ndd(nd_mapping);
- struct nd_namespace_label *nd_label;
- struct nd_namespace_index *nsindex;
- struct nd_label_ent *label_ent;
struct nd_label_id label_id;
struct resource *res;
- unsigned long *free;
- u32 nslot, slot;
- size_t offset;
u64 cookie;
- int rc;
-
- if (!preamble_next(ndd, &nsindex, &free, &nslot))
- return -ENXIO;
cookie = nd_region_interleave_set_cookie(nd_region, nsindex);
nd_label_gen_id(&label_id, nspm->uuid, 0);
@@ -916,33 +947,150 @@ static int __pmem_label_update(struct nd_region *nd_region,
return -ENXIO;
}
+ nsl_set_type(ndd, ns_label);
+ nsl_set_uuid(ndd, ns_label, nspm->uuid);
+ nsl_set_name(ndd, ns_label, nspm->alt_name);
+ nsl_set_flags(ndd, ns_label, flags);
+ nsl_set_nlabel(ndd, ns_label, nd_region->ndr_mappings);
+ nsl_set_nrange(ndd, ns_label, 1);
+ nsl_set_position(ndd, ns_label, pos);
+ nsl_set_isetcookie(ndd, ns_label, cookie);
+ nsl_set_rawsize(ndd, ns_label, resource_size(res));
+ nsl_set_lbasize(ndd, ns_label, nspm->lbasize);
+ nsl_set_dpa(ndd, ns_label, res->start);
+ nsl_set_slot(ndd, ns_label, slot);
+ nsl_set_alignment(ndd, ns_label, 0);
+ nsl_set_type_guid(ndd, ns_label, &nd_set->type_guid);
+ nsl_set_region_uuid(ndd, ns_label, &nd_set->uuid);
+ nsl_set_claim_class(ndd, ns_label, ndns->claim_class);
+ nsl_calculate_checksum(ndd, ns_label);
+ nd_dbg_dpa(nd_region, ndd, res, "\n");
+
+ return 0;
+}
+
+static void region_label_update(struct nd_region *nd_region,
+ struct cxl_region_label *region_label,
+ struct nd_mapping *nd_mapping,
+ int pos, u64 flags, u32 slot)
+{
+ struct nd_interleave_set *nd_set = nd_region->nd_set;
+ struct nvdimm_drvdata *ndd = to_ndd(nd_mapping);
+
+ /* Set Region Label Format identification UUID */
+ uuid_copy((uuid_t *)region_label->type, &cxl_region_uuid);
+
+ /* Set Current Region Label UUID */
+ export_uuid(region_label->uuid, &nd_set->uuid);
+
+ region_label->flags = __cpu_to_le32(flags);
+ region_label->nlabel = __cpu_to_le16(nd_region->ndr_mappings);
+ region_label->position = __cpu_to_le16(pos);
+ region_label->dpa = __cpu_to_le64(nd_mapping->start);
+ region_label->rawsize = __cpu_to_le64(nd_mapping->size);
+ region_label->hpa = __cpu_to_le64(nd_set->res->start);
+ region_label->slot = __cpu_to_le32(slot);
+ region_label->ig = __cpu_to_le32(nd_set->interleave_granularity);
+ region_label->align = __cpu_to_le32(0);
+
+ /* Update fletcher64 Checksum */
+ region_label_calculate_checksum(ndd, region_label);
+}
+
+static bool is_label_reapable(struct nd_interleave_set *nd_set,
+ struct nd_namespace_pmem *nspm,
+ struct nvdimm_drvdata *ndd,
+ struct nd_label_ent *label_ent,
+ enum label_type ltype,
+ unsigned long *flags)
+{
+ switch (ltype) {
+ case NS_LABEL_TYPE:
+ if (test_and_clear_bit(ND_LABEL_REAP, flags) ||
+ nsl_uuid_equal(ndd, label_ent->label, nspm->uuid))
+ return true;
+
+ break;
+ case RG_LABEL_TYPE:
+ if (region_label_uuid_equal(label_ent->region_label,
+ &nd_set->uuid))
+ return true;
+
+ break;
+ }
+
+ return false;
+}
+
+static bool is_label_present(struct nd_label_ent *label_ent,
+ enum label_type ltype)
+{
+ switch (ltype) {
+ case NS_LABEL_TYPE:
+ if (label_ent->label)
+ return true;
+
+ break;
+ case RG_LABEL_TYPE:
+ if (label_ent->region_label)
+ return true;
+
+ break;
+ }
+
+ return false;
+}
+
+static int __pmem_label_update(struct nd_region *nd_region,
+ struct nd_mapping *nd_mapping,
+ struct nd_namespace_pmem *nspm,
+ int pos, unsigned long flags,
+ enum label_type ltype)
+{
+ struct nd_interleave_set *nd_set = nd_region->nd_set;
+ struct nvdimm_drvdata *ndd = to_ndd(nd_mapping);
+ struct nd_namespace_index *nsindex;
+ struct nd_label_ent *label_ent;
+ union nd_lsa_label *lsa_label;
+ unsigned long *free;
+ struct device *dev;
+ u32 nslot, slot;
+ size_t offset;
+ int rc;
+
+ if (!preamble_next(ndd, &nsindex, &free, &nslot))
+ return -ENXIO;
+
/* allocate and write the label to the staging (next) index */
slot = nd_label_alloc_slot(ndd);
if (slot == UINT_MAX)
return -ENXIO;
dev_dbg(ndd->dev, "allocated: %d\n", slot);
- nd_label = to_label(ndd, slot);
- memset(nd_label, 0, sizeof_namespace_label(ndd));
- nsl_set_uuid(ndd, nd_label, nspm->uuid);
- nsl_set_name(ndd, nd_label, nspm->alt_name);
- nsl_set_flags(ndd, nd_label, flags);
- nsl_set_nlabel(ndd, nd_label, nd_region->ndr_mappings);
- nsl_set_nrange(ndd, nd_label, 1);
- nsl_set_position(ndd, nd_label, pos);
- nsl_set_isetcookie(ndd, nd_label, cookie);
- nsl_set_rawsize(ndd, nd_label, resource_size(res));
- nsl_set_lbasize(ndd, nd_label, nspm->lbasize);
- nsl_set_dpa(ndd, nd_label, res->start);
- nsl_set_slot(ndd, nd_label, slot);
- nsl_set_type_guid(ndd, nd_label, &nd_set->type_guid);
- nsl_set_claim_class(ndd, nd_label, ndns->claim_class);
- nsl_calculate_checksum(ndd, nd_label);
- nd_dbg_dpa(nd_region, ndd, res, "\n");
+ lsa_label = to_lsa_label(ndd, slot);
+ memset(lsa_label, 0, sizeof_namespace_label(ndd));
+
+ switch (ltype) {
+ case NS_LABEL_TYPE:
+ dev = &nspm->nsio.common.dev;
+ rc = namespace_label_update(nd_region, nd_mapping,
+ nspm, pos, flags, &lsa_label->ns_label,
+ nsindex, slot);
+ if (rc)
+ return rc;
+
+ break;
+ case RG_LABEL_TYPE:
+ dev = &nd_region->dev;
+ region_label_update(nd_region, &lsa_label->region_label,
+ nd_mapping, pos, flags, slot);
+
+ break;
+ }
/* update label */
- offset = nd_label_offset(ndd, nd_label);
- rc = nvdimm_set_config_data(ndd, offset, nd_label,
+ offset = nd_label_offset(ndd, lsa_label);
+ rc = nvdimm_set_config_data(ndd, offset, lsa_label,
sizeof_namespace_label(ndd));
if (rc < 0)
return rc;
@@ -950,10 +1098,11 @@ static int __pmem_label_update(struct nd_region *nd_region,
/* Garbage collect the previous label */
mutex_lock(&nd_mapping->lock);
list_for_each_entry(label_ent, &nd_mapping->labels, list) {
- if (!label_ent->label)
+ if (!is_label_present(label_ent, ltype))
continue;
- if (test_and_clear_bit(ND_LABEL_REAP, &label_ent->flags) ||
- nsl_uuid_equal(ndd, label_ent->label, nspm->uuid))
+
+ if (is_label_reapable(nd_set, nspm, ndd, label_ent, ltype,
+ &label_ent->flags))
reap_victim(nd_mapping, label_ent);
}
@@ -961,16 +1110,21 @@ static int __pmem_label_update(struct nd_region *nd_region,
rc = nd_label_write_index(ndd, ndd->ns_next,
nd_inc_seq(__le32_to_cpu(nsindex->seq)), 0);
if (rc == 0) {
- list_for_each_entry(label_ent, &nd_mapping->labels, list)
- if (!label_ent->label) {
- label_ent->label = nd_label;
- nd_label = NULL;
- break;
- }
- dev_WARN_ONCE(&nspm->nsio.common.dev, nd_label,
- "failed to track label: %d\n",
- to_slot(ndd, nd_label));
- if (nd_label)
+ list_for_each_entry(label_ent, &nd_mapping->labels, list) {
+ if (is_label_present(label_ent, ltype))
+ continue;
+
+ if (ltype == NS_LABEL_TYPE)
+ label_ent->label = &lsa_label->ns_label;
+ else
+ label_ent->region_label = &lsa_label->region_label;
+
+ lsa_label = NULL;
+ break;
+ }
+ dev_WARN_ONCE(dev, lsa_label, "failed to track label: %d\n",
+ to_lsa_slot(ndd, lsa_label));
+ if (lsa_label)
rc = -ENXIO;
}
mutex_unlock(&nd_mapping->lock);
@@ -978,7 +1132,8 @@ static int __pmem_label_update(struct nd_region *nd_region,
return rc;
}
-static int init_labels(struct nd_mapping *nd_mapping, int num_labels)
+static int init_labels(struct nd_mapping *nd_mapping, int num_labels,
+ enum label_type ltype)
{
int i, old_num_labels = 0;
struct nd_label_ent *label_ent;
@@ -998,6 +1153,16 @@ static int init_labels(struct nd_mapping *nd_mapping, int num_labels)
label_ent = kzalloc(sizeof(*label_ent), GFP_KERNEL);
if (!label_ent)
return -ENOMEM;
+
+ switch (ltype) {
+ case NS_LABEL_TYPE:
+ uuid_copy(&label_ent->label_uuid, &cxl_namespace_uuid);
+ break;
+ case RG_LABEL_TYPE:
+ uuid_copy(&label_ent->label_uuid, &cxl_region_uuid);
+ break;
+ }
+
mutex_lock(&nd_mapping->lock);
list_add_tail(&label_ent->list, &nd_mapping->labels);
mutex_unlock(&nd_mapping->lock);
@@ -1041,19 +1206,19 @@ static int del_labels(struct nd_mapping *nd_mapping, uuid_t *uuid)
mutex_lock(&nd_mapping->lock);
list_for_each_entry_safe(label_ent, e, &nd_mapping->labels, list) {
- struct nd_namespace_label *nd_label = label_ent->label;
-
- if (!nd_label)
+ if (label_ent->label)
continue;
active++;
- if (!nsl_uuid_equal(ndd, nd_label, uuid))
+ if (!nsl_uuid_equal(ndd, label_ent->label, uuid))
continue;
active--;
- slot = to_slot(ndd, nd_label);
+ slot = to_slot(ndd, label_ent);
nd_label_free_slot(ndd, slot);
dev_dbg(ndd->dev, "free: %d\n", slot);
list_move_tail(&label_ent->list, &list);
- label_ent->label = NULL;
+
+ if (uuid_equal(&cxl_namespace_uuid, &label_ent->label_uuid))
+ label_ent->label = NULL;
}
list_splice_tail_init(&list, &nd_mapping->labels);
@@ -1067,6 +1232,19 @@ static int del_labels(struct nd_mapping *nd_mapping, uuid_t *uuid)
nd_inc_seq(__le32_to_cpu(nsindex->seq)), 0);
}
+static int find_region_label_count(struct nd_mapping *nd_mapping)
+{
+ struct nd_label_ent *label_ent;
+ int region_label_cnt = 0;
+
+ guard(mutex)(&nd_mapping->lock);
+ list_for_each_entry(label_ent, &nd_mapping->labels, list)
+ if (uuid_equal(&cxl_region_uuid, &label_ent->label_uuid))
+ region_label_cnt++;
+
+ return region_label_cnt;
+}
+
int nd_pmem_namespace_label_update(struct nd_region *nd_region,
struct nd_namespace_pmem *nspm, resource_size_t size)
{
@@ -1075,6 +1253,7 @@ int nd_pmem_namespace_label_update(struct nd_region *nd_region,
for (i = 0; i < nd_region->ndr_mappings; i++) {
struct nd_mapping *nd_mapping = &nd_region->mapping[i];
struct nvdimm_drvdata *ndd = to_ndd(nd_mapping);
+ int region_label_cnt;
struct resource *res;
int count = 0;
@@ -1090,12 +1269,20 @@ int nd_pmem_namespace_label_update(struct nd_region *nd_region,
count++;
WARN_ON_ONCE(!count);
- rc = init_labels(nd_mapping, count);
+ region_label_cnt = find_region_label_count(nd_mapping);
+ /*
+ * init_labels() scan labels and allocate new label based
+ * on its second parameter (num_labels). Therefore to
+ * allocate new namespace label also include previously
+ * added region label
+ */
+ rc = init_labels(nd_mapping, count + region_label_cnt,
+ NS_LABEL_TYPE);
if (rc < 0)
return rc;
rc = __pmem_label_update(nd_region, nd_mapping, nspm, i,
- NSLABEL_FLAG_UPDATING);
+ NSLABEL_FLAG_UPDATING, NS_LABEL_TYPE);
if (rc)
return rc;
}
@@ -1107,7 +1294,48 @@ int nd_pmem_namespace_label_update(struct nd_region *nd_region,
for (i = 0; i < nd_region->ndr_mappings; i++) {
struct nd_mapping *nd_mapping = &nd_region->mapping[i];
- rc = __pmem_label_update(nd_region, nd_mapping, nspm, i, 0);
+ rc = __pmem_label_update(nd_region, nd_mapping, nspm, i, 0,
+ NS_LABEL_TYPE);
+ if (rc)
+ return rc;
+ }
+
+ return 0;
+}
+
+int nd_pmem_region_label_update(struct nd_region *nd_region)
+{
+ int i, rc;
+
+ for (i = 0; i < nd_region->ndr_mappings; i++) {
+ struct nd_mapping *nd_mapping = &nd_region->mapping[i];
+ struct nvdimm_drvdata *ndd = to_ndd(nd_mapping);
+ int region_label_cnt;
+
+ /* No need to update region label for non cxl format */
+ if (!ndd->cxl)
+ return 0;
+
+ region_label_cnt = find_region_label_count(nd_mapping);
+ rc = init_labels(nd_mapping, region_label_cnt + 1,
+ RG_LABEL_TYPE);
+ if (rc < 0)
+ return rc;
+
+ rc = __pmem_label_update(nd_region, nd_mapping, NULL, i,
+ NSLABEL_FLAG_UPDATING, RG_LABEL_TYPE);
+ if (rc)
+ return rc;
+ }
+
+ /* Clear the UPDATING flag per UEFI 2.7 expectations */
+ for (i = 0; i < nd_region->ndr_mappings; i++) {
+ struct nd_mapping *nd_mapping = &nd_region->mapping[i];
+ struct nvdimm_drvdata *ndd = to_ndd(nd_mapping);
+
+ WARN_ON_ONCE(!ndd->cxl);
+ rc = __pmem_label_update(nd_region, nd_mapping, NULL, i, 0,
+ RG_LABEL_TYPE);
if (rc)
return rc;
}
diff --git a/drivers/nvdimm/label.h b/drivers/nvdimm/label.h
index 0650fb4b9821..f11f54056353 100644
--- a/drivers/nvdimm/label.h
+++ b/drivers/nvdimm/label.h
@@ -30,6 +30,11 @@ enum {
ND_NSINDEX_INIT = 0x1,
};
+enum label_type {
+ RG_LABEL_TYPE,
+ NS_LABEL_TYPE,
+};
+
/**
* struct nd_namespace_index - label set superblock
* @sig: NAMESPACE_INDEX\0
@@ -183,6 +188,15 @@ struct nd_namespace_label {
};
};
+/*
+ * LSA 2.1 format introduces region label, which can also reside
+ * into LSA along with only namespace label as per v1.1 and v1.2
+ */
+union nd_lsa_label {
+ struct nd_namespace_label ns_label;
+ struct cxl_region_label region_label;
+};
+
#define NVDIMM_BTT_GUID "8aed63a2-29a2-4c66-8b12-f05d15d3922a"
#define NVDIMM_BTT2_GUID "18633bfc-1735-4217-8ac9-17239282d3f8"
#define NVDIMM_PFN_GUID "266400ba-fb9f-4677-bcb0-968f11d0d225"
@@ -215,7 +229,7 @@ struct nvdimm_drvdata;
int nd_label_data_init(struct nvdimm_drvdata *ndd);
size_t sizeof_namespace_index(struct nvdimm_drvdata *ndd);
int nd_label_active_count(struct nvdimm_drvdata *ndd);
-struct nd_namespace_label *nd_label_active(struct nvdimm_drvdata *ndd, int n);
+union nd_lsa_label *nd_label_active(struct nvdimm_drvdata *ndd, int n);
u32 nd_label_alloc_slot(struct nvdimm_drvdata *ndd);
bool nd_label_free_slot(struct nvdimm_drvdata *ndd, u32 slot);
u32 nd_label_nfree(struct nvdimm_drvdata *ndd);
@@ -223,4 +237,5 @@ struct nd_region;
struct nd_namespace_pmem;
int nd_pmem_namespace_label_update(struct nd_region *nd_region,
struct nd_namespace_pmem *nspm, resource_size_t size);
+int nd_pmem_region_label_update(struct nd_region *nd_region);
#endif /* __LABEL_H__ */
diff --git a/drivers/nvdimm/namespace_devs.c b/drivers/nvdimm/namespace_devs.c
index 43fdb806532e..657004021c95 100644
--- a/drivers/nvdimm/namespace_devs.c
+++ b/drivers/nvdimm/namespace_devs.c
@@ -232,6 +232,13 @@ static ssize_t __alt_name_store(struct device *dev, const char *buf,
return rc;
}
+int nd_region_label_update(struct nd_region *nd_region)
+{
+ guard(nvdimm_bus)(&nd_region->dev);
+ return nd_pmem_region_label_update(nd_region);
+}
+EXPORT_SYMBOL_GPL(nd_region_label_update);
+
static int nd_namespace_label_update(struct nd_region *nd_region,
struct device *dev)
{
@@ -2122,13 +2129,20 @@ static int init_active_labels(struct nd_region *nd_region)
if (!count)
continue;
for (j = 0; j < count; j++) {
- struct nd_namespace_label *label;
+ union nd_lsa_label *lsa_label;
label_ent = kzalloc(sizeof(*label_ent), GFP_KERNEL);
if (!label_ent)
break;
- label = nd_label_active(ndd, j);
- label_ent->label = label;
+
+ lsa_label = nd_label_active(ndd, j);
+ if (is_region_label(ndd, lsa_label)) {
+ label_ent->region_label = &lsa_label->region_label;
+ uuid_copy(&label_ent->label_uuid, &cxl_region_uuid);
+ } else {
+ label_ent->label = &lsa_label->ns_label;
+ uuid_copy(&label_ent->label_uuid, &cxl_namespace_uuid);
+ }
mutex_lock(&nd_mapping->lock);
list_add_tail(&label_ent->list, &nd_mapping->labels);
diff --git a/drivers/nvdimm/nd.h b/drivers/nvdimm/nd.h
index f631bd84d6f0..1b31eee3028e 100644
--- a/drivers/nvdimm/nd.h
+++ b/drivers/nvdimm/nd.h
@@ -14,6 +14,9 @@
#include <linux/nd.h>
#include "label.h"
+extern uuid_t cxl_namespace_uuid;
+extern uuid_t cxl_region_uuid;
+
enum {
/*
* Limits the maximum number of block apertures a dimm can
@@ -295,6 +298,52 @@ static inline const u8 *nsl_uuid_raw(struct nvdimm_drvdata *ndd,
return nd_label->efi.uuid;
}
+static inline void nsl_set_type(struct nvdimm_drvdata *ndd,
+ struct nd_namespace_label *ns_label)
+{
+ if (!(ndd->cxl && ns_label))
+ return;
+
+ export_uuid(ns_label->cxl.type, &cxl_namespace_uuid);
+}
+
+static inline void nsl_set_alignment(struct nvdimm_drvdata *ndd,
+ struct nd_namespace_label *ns_label,
+ u32 align)
+{
+ if (!ndd->cxl)
+ return;
+
+ ns_label->cxl.align = __cpu_to_le32(align);
+}
+
+static inline void nsl_set_region_uuid(struct nvdimm_drvdata *ndd,
+ struct nd_namespace_label *ns_label,
+ const uuid_t *uuid)
+{
+ if (!(ndd->cxl && uuid))
+ return;
+
+ export_uuid(ns_label->cxl.region_uuid, uuid);
+}
+
+static inline bool is_region_label(struct nvdimm_drvdata *ndd,
+ union nd_lsa_label *lsa_label)
+{
+ if (!ndd->cxl)
+ return false;
+
+ return uuid_equal(&cxl_region_uuid,
+ (uuid_t *)lsa_label->region_label.type);
+}
+
+static inline bool
+region_label_uuid_equal(struct cxl_region_label *region_label,
+ const uuid_t *uuid)
+{
+ return uuid_equal((uuid_t *)region_label->uuid, uuid);
+}
+
bool nsl_validate_type_guid(struct nvdimm_drvdata *ndd,
struct nd_namespace_label *nd_label, guid_t *guid);
enum nvdimm_claim_class nsl_get_claim_class(struct nvdimm_drvdata *ndd,
@@ -376,7 +425,9 @@ enum nd_label_flags {
struct nd_label_ent {
struct list_head list;
unsigned long flags;
+ uuid_t label_uuid;
struct nd_namespace_label *label;
+ struct cxl_region_label *region_label;
};
enum nd_mapping_lock_class {
diff --git a/include/linux/libnvdimm.h b/include/linux/libnvdimm.h
index 5696715c33bb..2c213b9dac66 100644
--- a/include/linux/libnvdimm.h
+++ b/include/linux/libnvdimm.h
@@ -117,6 +117,13 @@ struct nd_interleave_set {
u64 altcookie;
guid_t type_guid;
+
+ /* v2.1 region label info */
+ uuid_t uuid;
+ int interleave_ways;
+ int interleave_granularity;
+ struct resource *res;
+ int nr_targets;
};
struct nd_mapping_desc {
@@ -307,6 +314,7 @@ int nvdimm_has_flush(struct nd_region *nd_region);
int nvdimm_has_cache(struct nd_region *nd_region);
int nvdimm_in_overwrite(struct nvdimm *nvdimm);
bool is_nvdimm_sync(struct nd_region *nd_region);
+int nd_region_label_update(struct nd_region *nd_region);
static inline int nvdimm_ctl(struct nvdimm *nvdimm, unsigned int cmd, void *buf,
unsigned int buf_len, int *cmd_rc)
--
2.34.1
^ permalink raw reply related [flat|nested] 53+ messages in thread
* [PATCH V5 04/17] nvdimm/label: Include region label in slot validation
2026-01-09 12:44 ` [PATCH V5 00/17] Add CXL LSA 2.1 format support in nvdimm and cxl pmem Neeraj Kumar
` (2 preceding siblings ...)
2026-01-09 12:44 ` [PATCH V5 03/17] nvdimm/label: Add namespace/region label support as per LSA 2.1 Neeraj Kumar
@ 2026-01-09 12:44 ` Neeraj Kumar
2026-01-14 21:20 ` Ira Weiny
` (2 more replies)
2026-01-09 12:44 ` [PATCH V5 05/17] nvdimm/label: Skip region label during ns label DPA reservation Neeraj Kumar
` (13 subsequent siblings)
17 siblings, 3 replies; 53+ messages in thread
From: Neeraj Kumar @ 2026-01-09 12:44 UTC (permalink / raw)
To: linux-cxl, nvdimm, linux-kernel, gost.dev
Cc: a.manzanares, vishak.g, neeraj.kernel, Neeraj Kumar
Prior to LSA 2.1 Support, label in slot means only namespace
label. But with LSA 2.1 a label can be either namespace or
region label.
Slot validation routine validates label slot by calculating
label checksum. It was only validating namespace label.
This changeset also validates region label if present.
In previous patch to_lsa_label() was introduced along with
to_label(). to_label() returns only namespace label whereas
to_lsa_label() returns union nd_lsa_label*
In this patch We have converted all usage of to_label()
to to_lsa_label()
Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Neeraj Kumar <s.neeraj@samsung.com>
---
drivers/nvdimm/label.c | 94 ++++++++++++++++++++++++++++--------------
1 file changed, 64 insertions(+), 30 deletions(-)
diff --git a/drivers/nvdimm/label.c b/drivers/nvdimm/label.c
index 17e2a1f5a6da..9854cb45fb62 100644
--- a/drivers/nvdimm/label.c
+++ b/drivers/nvdimm/label.c
@@ -312,16 +312,6 @@ static union nd_lsa_label *to_lsa_label(struct nvdimm_drvdata *ndd, int slot)
return (union nd_lsa_label *) label;
}
-static struct nd_namespace_label *to_label(struct nvdimm_drvdata *ndd, int slot)
-{
- unsigned long label, base;
-
- base = (unsigned long) nd_label_base(ndd);
- label = base + sizeof_namespace_label(ndd) * slot;
-
- return (struct nd_namespace_label *) label;
-}
-
#define for_each_clear_bit_le(bit, addr, size) \
for ((bit) = find_next_zero_bit_le((addr), (size), 0); \
(bit) < (size); \
@@ -382,7 +372,7 @@ static bool nsl_validate_checksum(struct nvdimm_drvdata *ndd,
{
u64 sum, sum_save;
- if (!ndd->cxl && !efi_namespace_label_has(ndd, checksum))
+ if (!efi_namespace_label_has(ndd, checksum))
return true;
sum_save = nsl_get_checksum(ndd, nd_label);
@@ -397,13 +387,25 @@ static void nsl_calculate_checksum(struct nvdimm_drvdata *ndd,
{
u64 sum;
- if (!ndd->cxl && !efi_namespace_label_has(ndd, checksum))
+ if (!efi_namespace_label_has(ndd, checksum))
return;
nsl_set_checksum(ndd, nd_label, 0);
sum = nd_fletcher64(nd_label, sizeof_namespace_label(ndd), 1);
nsl_set_checksum(ndd, nd_label, sum);
}
+static bool region_label_validate_checksum(struct nvdimm_drvdata *ndd,
+ struct cxl_region_label *region_label)
+{
+ u64 sum, sum_save;
+
+ sum_save = __le64_to_cpu(region_label->checksum);
+ region_label->checksum = __cpu_to_le64(0);
+ sum = nd_fletcher64(region_label, sizeof_namespace_label(ndd), 1);
+ region_label->checksum = __cpu_to_le64(sum_save);
+ return sum == sum_save;
+}
+
static void region_label_calculate_checksum(struct nvdimm_drvdata *ndd,
struct cxl_region_label *region_label)
{
@@ -415,16 +417,34 @@ static void region_label_calculate_checksum(struct nvdimm_drvdata *ndd,
}
static bool slot_valid(struct nvdimm_drvdata *ndd,
- struct nd_namespace_label *nd_label, u32 slot)
+ union nd_lsa_label *lsa_label, u32 slot)
{
+ struct cxl_region_label *region_label = &lsa_label->region_label;
+ struct nd_namespace_label *nd_label = &lsa_label->ns_label;
+ enum label_type type;
bool valid;
+ static const char * const label_name[] = {
+ [RG_LABEL_TYPE] = "region",
+ [NS_LABEL_TYPE] = "namespace",
+ };
/* check that we are written where we expect to be written */
- if (slot != nsl_get_slot(ndd, nd_label))
- return false;
- valid = nsl_validate_checksum(ndd, nd_label);
+ if (is_region_label(ndd, lsa_label)) {
+ type = RG_LABEL_TYPE;
+ if (slot != __le32_to_cpu(region_label->slot))
+ return false;
+ valid = region_label_validate_checksum(ndd, region_label);
+ } else {
+ type = NS_LABEL_TYPE;
+ if (slot != nsl_get_slot(ndd, nd_label))
+ return false;
+ valid = nsl_validate_checksum(ndd, nd_label);
+ }
+
if (!valid)
- dev_dbg(ndd->dev, "fail checksum. slot: %d\n", slot);
+ dev_dbg(ndd->dev, "%s label checksum fail. slot: %d\n",
+ label_name[type], slot);
+
return valid;
}
@@ -440,14 +460,16 @@ int nd_label_reserve_dpa(struct nvdimm_drvdata *ndd)
for_each_clear_bit_le(slot, free, nslot) {
struct nd_namespace_label *nd_label;
struct nd_region *nd_region = NULL;
+ union nd_lsa_label *lsa_label;
struct nd_label_id label_id;
struct resource *res;
uuid_t label_uuid;
u32 flags;
- nd_label = to_label(ndd, slot);
+ lsa_label = to_lsa_label(ndd, slot);
+ nd_label = &lsa_label->ns_label;
- if (!slot_valid(ndd, nd_label, slot))
+ if (!slot_valid(ndd, lsa_label, slot))
continue;
nsl_get_uuid(ndd, nd_label, &label_uuid);
@@ -598,18 +620,30 @@ int nd_label_active_count(struct nvdimm_drvdata *ndd)
return 0;
for_each_clear_bit_le(slot, free, nslot) {
+ struct cxl_region_label *region_label;
struct nd_namespace_label *nd_label;
-
- nd_label = to_label(ndd, slot);
-
- if (!slot_valid(ndd, nd_label, slot)) {
- u32 label_slot = nsl_get_slot(ndd, nd_label);
- u64 size = nsl_get_rawsize(ndd, nd_label);
- u64 dpa = nsl_get_dpa(ndd, nd_label);
+ union nd_lsa_label *lsa_label;
+ u32 lslot;
+ u64 size, dpa;
+
+ lsa_label = to_lsa_label(ndd, slot);
+ nd_label = &lsa_label->ns_label;
+ region_label = &lsa_label->region_label;
+
+ if (!slot_valid(ndd, lsa_label, slot)) {
+ if (is_region_label(ndd, lsa_label)) {
+ lslot = __le32_to_cpu(region_label->slot);
+ size = __le64_to_cpu(region_label->rawsize);
+ dpa = __le64_to_cpu(region_label->dpa);
+ } else {
+ lslot = nsl_get_slot(ndd, nd_label);
+ size = nsl_get_rawsize(ndd, nd_label);
+ dpa = nsl_get_dpa(ndd, nd_label);
+ }
dev_dbg(ndd->dev,
"slot%d invalid slot: %d dpa: %llx size: %llx\n",
- slot, label_slot, dpa, size);
+ slot, lslot, dpa, size);
continue;
}
count++;
@@ -627,10 +661,10 @@ union nd_lsa_label *nd_label_active(struct nvdimm_drvdata *ndd, int n)
return NULL;
for_each_clear_bit_le(slot, free, nslot) {
- struct nd_namespace_label *nd_label;
+ union nd_lsa_label *lsa_label;
- nd_label = to_label(ndd, slot);
- if (!slot_valid(ndd, nd_label, slot))
+ lsa_label = to_lsa_label(ndd, slot);
+ if (!slot_valid(ndd, lsa_label, slot))
continue;
if (n-- == 0)
--
2.34.1
^ permalink raw reply related [flat|nested] 53+ messages in thread
* [PATCH V5 05/17] nvdimm/label: Skip region label during ns label DPA reservation
2026-01-09 12:44 ` [PATCH V5 00/17] Add CXL LSA 2.1 format support in nvdimm and cxl pmem Neeraj Kumar
` (3 preceding siblings ...)
2026-01-09 12:44 ` [PATCH V5 04/17] nvdimm/label: Include region label in slot validation Neeraj Kumar
@ 2026-01-09 12:44 ` Neeraj Kumar
2026-01-15 17:56 ` Jonathan Cameron
2026-01-21 0:41 ` Ira Weiny
2026-01-09 12:44 ` [PATCH V5 06/17] nvdimm/label: Preserve region label during namespace creation Neeraj Kumar
` (12 subsequent siblings)
17 siblings, 2 replies; 53+ messages in thread
From: Neeraj Kumar @ 2026-01-09 12:44 UTC (permalink / raw)
To: linux-cxl, nvdimm, linux-kernel, gost.dev
Cc: a.manzanares, vishak.g, neeraj.kernel, Neeraj Kumar
CXL 3.2 Spec mentions CXL LSA 2.1 Namespace Labels at section
9.13.2.5. If Namespace label is present in LSA during
nvdimm_probe() then dimm-physical-address(DPA) reservation is
required. But this reservation is not required by cxl region
label. Therefore if LSA scanning finds any region label, skip it.
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Neeraj Kumar <s.neeraj@samsung.com>
---
drivers/nvdimm/label.c | 8 ++++++++
1 file changed, 8 insertions(+)
diff --git a/drivers/nvdimm/label.c b/drivers/nvdimm/label.c
index 9854cb45fb62..169692dfa12c 100644
--- a/drivers/nvdimm/label.c
+++ b/drivers/nvdimm/label.c
@@ -469,6 +469,14 @@ int nd_label_reserve_dpa(struct nvdimm_drvdata *ndd)
lsa_label = to_lsa_label(ndd, slot);
nd_label = &lsa_label->ns_label;
+ /*
+ * Skip region label. If LSA label is region label
+ * then it don't require dimm-physical-address(DPA)
+ * reservation. Whereas its required for namespace label
+ */
+ if (is_region_label(ndd, lsa_label))
+ continue;
+
if (!slot_valid(ndd, lsa_label, slot))
continue;
--
2.34.1
^ permalink raw reply related [flat|nested] 53+ messages in thread
* [PATCH V5 06/17] nvdimm/label: Preserve region label during namespace creation
2026-01-09 12:44 ` [PATCH V5 00/17] Add CXL LSA 2.1 format support in nvdimm and cxl pmem Neeraj Kumar
` (4 preceding siblings ...)
2026-01-09 12:44 ` [PATCH V5 05/17] nvdimm/label: Skip region label during ns label DPA reservation Neeraj Kumar
@ 2026-01-09 12:44 ` Neeraj Kumar
2026-01-15 17:59 ` Jonathan Cameron
2026-01-21 0:43 ` Ira Weiny
2026-01-09 12:44 ` [PATCH V5 07/17] nvdimm/label: Add region label delete support Neeraj Kumar
` (11 subsequent siblings)
17 siblings, 2 replies; 53+ messages in thread
From: Neeraj Kumar @ 2026-01-09 12:44 UTC (permalink / raw)
To: linux-cxl, nvdimm, linux-kernel, gost.dev
Cc: a.manzanares, vishak.g, neeraj.kernel, Neeraj Kumar
During namespace creation we scan labels present in LSA using
scan_labels(). Currently scan_labels() is only preserving
namespace labels into label_ent list.
In this patch we also preserve region label into label_ent list
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Neeraj Kumar <s.neeraj@samsung.com>
---
drivers/nvdimm/namespace_devs.c | 47 +++++++++++++++++++++++++++++----
1 file changed, 42 insertions(+), 5 deletions(-)
diff --git a/drivers/nvdimm/namespace_devs.c b/drivers/nvdimm/namespace_devs.c
index 657004021c95..8411f4152319 100644
--- a/drivers/nvdimm/namespace_devs.c
+++ b/drivers/nvdimm/namespace_devs.c
@@ -1994,9 +1994,32 @@ static struct device **scan_labels(struct nd_region *nd_region)
if (count == 0) {
struct nd_namespace_pmem *nspm;
+ for (i = 0; i < nd_region->ndr_mappings; i++) {
+ struct cxl_region_label *region_label;
+ struct nd_label_ent *le, *e;
+ LIST_HEAD(list);
- /* Publish a zero-sized namespace for userspace to configure. */
- nd_mapping_free_labels(nd_mapping);
+ nd_mapping = &nd_region->mapping[i];
+ if (list_empty(&nd_mapping->labels))
+ continue;
+
+ list_for_each_entry_safe(le, e, &nd_mapping->labels,
+ list) {
+ region_label = le->region_label;
+ if (!region_label)
+ continue;
+
+ /* Preserve region labels if present */
+ list_move_tail(&le->list, &list);
+ }
+
+ /*
+ * Publish a zero-sized namespace for userspace
+ * to configure.
+ */
+ nd_mapping_free_labels(nd_mapping);
+ list_splice_init(&list, &nd_mapping->labels);
+ }
nspm = kzalloc(sizeof(*nspm), GFP_KERNEL);
if (!nspm)
goto err;
@@ -2008,7 +2031,7 @@ static struct device **scan_labels(struct nd_region *nd_region)
} else if (is_memory(&nd_region->dev)) {
/* clean unselected labels */
for (i = 0; i < nd_region->ndr_mappings; i++) {
- struct list_head *l, *e;
+ struct nd_label_ent *le, *e;
LIST_HEAD(list);
int j;
@@ -2019,10 +2042,24 @@ static struct device **scan_labels(struct nd_region *nd_region)
}
j = count;
- list_for_each_safe(l, e, &nd_mapping->labels) {
+ list_for_each_entry_safe(le, e, &nd_mapping->labels,
+ list) {
+ /* Preserve region labels */
+ if (uuid_equal(&le->label_uuid,
+ &cxl_region_uuid)) {
+ list_move_tail(&le->list, &list);
+ continue;
+ }
+
+ /*
+ * Once preserving selected ns label done
+ * break out of loop
+ */
if (!j--)
break;
- list_move_tail(l, &list);
+
+ /* Preserve selected ns label */
+ list_move_tail(&le->list, &list);
}
nd_mapping_free_labels(nd_mapping);
list_splice_init(&list, &nd_mapping->labels);
--
2.34.1
^ permalink raw reply related [flat|nested] 53+ messages in thread
* [PATCH V5 07/17] nvdimm/label: Add region label delete support
2026-01-09 12:44 ` [PATCH V5 00/17] Add CXL LSA 2.1 format support in nvdimm and cxl pmem Neeraj Kumar
` (5 preceding siblings ...)
2026-01-09 12:44 ` [PATCH V5 06/17] nvdimm/label: Preserve region label during namespace creation Neeraj Kumar
@ 2026-01-09 12:44 ` Neeraj Kumar
2026-01-21 0:44 ` Ira Weiny
2026-01-09 12:44 ` [PATCH V5 08/17] nvdimm/label: Preserve cxl region information from region label Neeraj Kumar
` (10 subsequent siblings)
17 siblings, 1 reply; 53+ messages in thread
From: Neeraj Kumar @ 2026-01-09 12:44 UTC (permalink / raw)
To: linux-cxl, nvdimm, linux-kernel, gost.dev
Cc: a.manzanares, vishak.g, neeraj.kernel, Neeraj Kumar
Create export routine nd_region_label_delete() used for deleting
region label from LSA. It will be used later from CXL subsystem
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>
Signed-off-by: Neeraj Kumar <s.neeraj@samsung.com>
---
drivers/nvdimm/label.c | 74 ++++++++++++++++++++++++++++++---
drivers/nvdimm/label.h | 1 +
drivers/nvdimm/namespace_devs.c | 7 ++++
drivers/nvdimm/nd.h | 6 +++
include/linux/libnvdimm.h | 1 +
5 files changed, 83 insertions(+), 6 deletions(-)
diff --git a/drivers/nvdimm/label.c b/drivers/nvdimm/label.c
index 169692dfa12c..2ad148bfe40b 100644
--- a/drivers/nvdimm/label.c
+++ b/drivers/nvdimm/label.c
@@ -1229,7 +1229,8 @@ static int init_labels(struct nd_mapping *nd_mapping, int num_labels,
return max(num_labels, old_num_labels);
}
-static int del_labels(struct nd_mapping *nd_mapping, uuid_t *uuid)
+static int del_labels(struct nd_mapping *nd_mapping, uuid_t *uuid,
+ enum label_type ltype)
{
struct nvdimm_drvdata *ndd = to_ndd(nd_mapping);
struct nd_label_ent *label_ent, *e;
@@ -1248,11 +1249,24 @@ static int del_labels(struct nd_mapping *nd_mapping, uuid_t *uuid)
mutex_lock(&nd_mapping->lock);
list_for_each_entry_safe(label_ent, e, &nd_mapping->labels, list) {
- if (label_ent->label)
+ if ((ltype == NS_LABEL_TYPE && !label_ent->label) ||
+ (ltype == RG_LABEL_TYPE && !label_ent->region_label))
continue;
active++;
- if (!nsl_uuid_equal(ndd, label_ent->label, uuid))
- continue;
+
+ switch (ltype) {
+ case NS_LABEL_TYPE:
+ if (!nsl_uuid_equal(ndd, label_ent->label, uuid))
+ continue;
+
+ break;
+ case RG_LABEL_TYPE:
+ if (!region_label_uuid_equal(label_ent->region_label, uuid))
+ continue;
+
+ break;
+ }
+
active--;
slot = to_slot(ndd, label_ent);
nd_label_free_slot(ndd, slot);
@@ -1261,10 +1275,12 @@ static int del_labels(struct nd_mapping *nd_mapping, uuid_t *uuid)
if (uuid_equal(&cxl_namespace_uuid, &label_ent->label_uuid))
label_ent->label = NULL;
+ else
+ label_ent->region_label = NULL;
}
list_splice_tail_init(&list, &nd_mapping->labels);
- if (active == 0) {
+ if ((ltype == NS_LABEL_TYPE) && (active == 0)) {
nd_mapping_free_labels(nd_mapping);
dev_dbg(ndd->dev, "no more active labels\n");
}
@@ -1300,7 +1316,8 @@ int nd_pmem_namespace_label_update(struct nd_region *nd_region,
int count = 0;
if (size == 0) {
- rc = del_labels(nd_mapping, nspm->uuid);
+ rc = del_labels(nd_mapping, nspm->uuid,
+ NS_LABEL_TYPE);
if (rc)
return rc;
continue;
@@ -1385,6 +1402,51 @@ int nd_pmem_region_label_update(struct nd_region *nd_region)
return 0;
}
+int nd_pmem_region_label_delete(struct nd_region *nd_region)
+{
+ struct nd_interleave_set *nd_set = nd_region->nd_set;
+ struct nd_label_ent *label_ent;
+ int i, rc;
+
+ for (i = 0; i < nd_region->ndr_mappings; i++) {
+ struct nd_mapping *nd_mapping = &nd_region->mapping[i];
+ struct nvdimm_drvdata *ndd = to_ndd(nd_mapping);
+
+ /* Find non cxl format supported ndr_mappings */
+ if (!ndd->cxl) {
+ dev_info(&nd_region->dev, "Unsupported region label\n");
+ return -EINVAL;
+ }
+
+ /* Find if any NS label using this region */
+ guard(mutex)(&nd_mapping->lock);
+ list_for_each_entry(label_ent, &nd_mapping->labels, list) {
+ if (!label_ent->label)
+ continue;
+
+ /*
+ * Check if any available NS labels has same
+ * region_uuid in LSA
+ */
+ if (nsl_region_uuid_equal(label_ent->label,
+ &nd_set->uuid)) {
+ dev_dbg(&nd_region->dev,
+ "Region/Namespace label in use\n");
+ return -EBUSY;
+ }
+ }
+ }
+
+ for (i = 0; i < nd_region->ndr_mappings; i++) {
+ rc = del_labels(&nd_region->mapping[i], &nd_set->uuid,
+ RG_LABEL_TYPE);
+ if (rc)
+ return rc;
+ }
+
+ return 0;
+}
+
int __init nd_label_init(void)
{
WARN_ON(guid_parse(NVDIMM_BTT_GUID, &nvdimm_btt_guid));
diff --git a/drivers/nvdimm/label.h b/drivers/nvdimm/label.h
index f11f54056353..80a7f7dd8ba7 100644
--- a/drivers/nvdimm/label.h
+++ b/drivers/nvdimm/label.h
@@ -238,4 +238,5 @@ struct nd_namespace_pmem;
int nd_pmem_namespace_label_update(struct nd_region *nd_region,
struct nd_namespace_pmem *nspm, resource_size_t size);
int nd_pmem_region_label_update(struct nd_region *nd_region);
+int nd_pmem_region_label_delete(struct nd_region *nd_region);
#endif /* __LABEL_H__ */
diff --git a/drivers/nvdimm/namespace_devs.c b/drivers/nvdimm/namespace_devs.c
index 8411f4152319..9047826138be 100644
--- a/drivers/nvdimm/namespace_devs.c
+++ b/drivers/nvdimm/namespace_devs.c
@@ -239,6 +239,13 @@ int nd_region_label_update(struct nd_region *nd_region)
}
EXPORT_SYMBOL_GPL(nd_region_label_update);
+int nd_region_label_delete(struct nd_region *nd_region)
+{
+ guard(nvdimm_bus)(&nd_region->dev);
+ return nd_pmem_region_label_delete(nd_region);
+}
+EXPORT_SYMBOL_GPL(nd_region_label_delete);
+
static int nd_namespace_label_update(struct nd_region *nd_region,
struct device *dev)
{
diff --git a/drivers/nvdimm/nd.h b/drivers/nvdimm/nd.h
index 1b31eee3028e..92a8eabe0792 100644
--- a/drivers/nvdimm/nd.h
+++ b/drivers/nvdimm/nd.h
@@ -337,6 +337,12 @@ static inline bool is_region_label(struct nvdimm_drvdata *ndd,
(uuid_t *)lsa_label->region_label.type);
}
+static inline bool nsl_region_uuid_equal(struct nd_namespace_label *ns_label,
+ const uuid_t *uuid)
+{
+ return uuid_equal((uuid_t *)ns_label->cxl.region_uuid, uuid);
+}
+
static inline bool
region_label_uuid_equal(struct cxl_region_label *region_label,
const uuid_t *uuid)
diff --git a/include/linux/libnvdimm.h b/include/linux/libnvdimm.h
index 2c213b9dac66..bbf14a260c93 100644
--- a/include/linux/libnvdimm.h
+++ b/include/linux/libnvdimm.h
@@ -315,6 +315,7 @@ int nvdimm_has_cache(struct nd_region *nd_region);
int nvdimm_in_overwrite(struct nvdimm *nvdimm);
bool is_nvdimm_sync(struct nd_region *nd_region);
int nd_region_label_update(struct nd_region *nd_region);
+int nd_region_label_delete(struct nd_region *nd_region);
static inline int nvdimm_ctl(struct nvdimm *nvdimm, unsigned int cmd, void *buf,
unsigned int buf_len, int *cmd_rc)
--
2.34.1
^ permalink raw reply related [flat|nested] 53+ messages in thread
* [PATCH V5 08/17] nvdimm/label: Preserve cxl region information from region label
2026-01-09 12:44 ` [PATCH V5 00/17] Add CXL LSA 2.1 format support in nvdimm and cxl pmem Neeraj Kumar
` (6 preceding siblings ...)
2026-01-09 12:44 ` [PATCH V5 07/17] nvdimm/label: Add region label delete support Neeraj Kumar
@ 2026-01-09 12:44 ` Neeraj Kumar
2026-01-15 18:03 ` Jonathan Cameron
2026-01-21 0:45 ` Ira Weiny
2026-01-09 12:44 ` [PATCH V5 09/17] nvdimm/label: Export routine to fetch region information Neeraj Kumar
` (9 subsequent siblings)
17 siblings, 2 replies; 53+ messages in thread
From: Neeraj Kumar @ 2026-01-09 12:44 UTC (permalink / raw)
To: linux-cxl, nvdimm, linux-kernel, gost.dev
Cc: a.manzanares, vishak.g, neeraj.kernel, Neeraj Kumar
Preserve region information from region label during nvdimm_probe. This
preserved region information is used for creating cxl region to achieve
region persistency across reboot.
This patch supports interleave way == 1, it is therefore it preserves
only one region into LSA
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Neeraj Kumar <s.neeraj@samsung.com>
---
drivers/nvdimm/dimm.c | 4 ++++
drivers/nvdimm/label.c | 36 ++++++++++++++++++++++++++++++++++++
drivers/nvdimm/nd-core.h | 2 ++
drivers/nvdimm/nd.h | 1 +
include/linux/libnvdimm.h | 14 ++++++++++++++
5 files changed, 57 insertions(+)
diff --git a/drivers/nvdimm/dimm.c b/drivers/nvdimm/dimm.c
index 07f5c5d5e537..590ec883903d 100644
--- a/drivers/nvdimm/dimm.c
+++ b/drivers/nvdimm/dimm.c
@@ -107,6 +107,10 @@ static int nvdimm_probe(struct device *dev)
if (rc)
goto err;
+ /* Preserve cxl region info if available */
+ if (ndd->cxl)
+ nvdimm_cxl_region_preserve(ndd);
+
return 0;
err:
diff --git a/drivers/nvdimm/label.c b/drivers/nvdimm/label.c
index 2ad148bfe40b..7adb415f0926 100644
--- a/drivers/nvdimm/label.c
+++ b/drivers/nvdimm/label.c
@@ -494,6 +494,42 @@ int nd_label_reserve_dpa(struct nvdimm_drvdata *ndd)
return 0;
}
+int nvdimm_cxl_region_preserve(struct nvdimm_drvdata *ndd)
+{
+ struct nvdimm *nvdimm = to_nvdimm(ndd->dev);
+ struct cxl_pmem_region_params *p = &nvdimm->cxl_region_params;
+ struct nd_namespace_index *nsindex;
+ unsigned long *free;
+ u32 nslot, slot;
+
+ if (!preamble_current(ndd, &nsindex, &free, &nslot))
+ return 0; /* no label, nothing to preserve */
+
+ for_each_clear_bit_le(slot, free, nslot) {
+ union nd_lsa_label *lsa_label = to_lsa_label(ndd, slot);
+ struct cxl_region_label *region_label = &lsa_label->region_label;
+ uuid_t *region_uuid = (uuid_t *)®ion_label->type;
+
+ /* TODO: Currently preserving only one region */
+ if (uuid_equal(&cxl_region_uuid, region_uuid)) {
+ nvdimm->is_region_label = true;
+ import_uuid(&p->uuid, region_label->uuid);
+ p->flags = __le32_to_cpu(region_label->flags);
+ p->nlabel = __le16_to_cpu(region_label->nlabel);
+ p->position = __le16_to_cpu(region_label->position);
+ p->dpa = __le64_to_cpu(region_label->dpa);
+ p->rawsize = __le64_to_cpu(region_label->rawsize);
+ p->hpa = __le64_to_cpu(region_label->hpa);
+ p->slot = __le32_to_cpu(region_label->slot);
+ p->ig = __le32_to_cpu(region_label->ig);
+ p->align = __le32_to_cpu(region_label->align);
+ break;
+ }
+ }
+
+ return 0;
+}
+
int nd_label_data_init(struct nvdimm_drvdata *ndd)
{
size_t config_size, read_size, max_xfer, offset;
diff --git a/drivers/nvdimm/nd-core.h b/drivers/nvdimm/nd-core.h
index bfc6bfeb6e24..a73fac81531e 100644
--- a/drivers/nvdimm/nd-core.h
+++ b/drivers/nvdimm/nd-core.h
@@ -46,6 +46,8 @@ struct nvdimm {
} sec;
struct delayed_work dwork;
const struct nvdimm_fw_ops *fw_ops;
+ bool is_region_label;
+ struct cxl_pmem_region_params cxl_region_params;
};
static inline unsigned long nvdimm_security_flags(
diff --git a/drivers/nvdimm/nd.h b/drivers/nvdimm/nd.h
index 92a8eabe0792..86837de7f183 100644
--- a/drivers/nvdimm/nd.h
+++ b/drivers/nvdimm/nd.h
@@ -580,6 +580,7 @@ void nvdimm_set_locked(struct device *dev);
void nvdimm_clear_locked(struct device *dev);
int nvdimm_security_setup_events(struct device *dev);
bool nvdimm_region_label_supported(struct device *dev);
+int nvdimm_cxl_region_preserve(struct nvdimm_drvdata *ndd);
#if IS_ENABLED(CONFIG_NVDIMM_KEYS)
int nvdimm_security_unlock(struct device *dev);
#else
diff --git a/include/linux/libnvdimm.h b/include/linux/libnvdimm.h
index bbf14a260c93..07ea2e3f821a 100644
--- a/include/linux/libnvdimm.h
+++ b/include/linux/libnvdimm.h
@@ -108,6 +108,20 @@ struct nd_cmd_desc {
int out_sizes[ND_CMD_MAX_ELEM];
};
+struct cxl_pmem_region_params {
+ uuid_t uuid;
+ u32 flags;
+ u16 nlabel;
+ u16 position;
+ u64 dpa;
+ u64 rawsize;
+ u64 hpa;
+ u32 slot;
+ u32 ig;
+ u32 align;
+ int nr_targets;
+};
+
struct nd_interleave_set {
/* v1.1 definition of the interleave-set-cookie algorithm */
u64 cookie1;
--
2.34.1
^ permalink raw reply related [flat|nested] 53+ messages in thread
* [PATCH V5 09/17] nvdimm/label: Export routine to fetch region information
2026-01-09 12:44 ` [PATCH V5 00/17] Add CXL LSA 2.1 format support in nvdimm and cxl pmem Neeraj Kumar
` (7 preceding siblings ...)
2026-01-09 12:44 ` [PATCH V5 08/17] nvdimm/label: Preserve cxl region information from region label Neeraj Kumar
@ 2026-01-09 12:44 ` Neeraj Kumar
2026-01-15 18:03 ` Jonathan Cameron
2026-01-21 0:46 ` Ira Weiny
2026-01-09 12:44 ` [PATCH V5 10/17] cxl/mem: Refactor cxl pmem region auto-assembling Neeraj Kumar
` (8 subsequent siblings)
17 siblings, 2 replies; 53+ messages in thread
From: Neeraj Kumar @ 2026-01-09 12:44 UTC (permalink / raw)
To: linux-cxl, nvdimm, linux-kernel, gost.dev
Cc: a.manzanares, vishak.g, neeraj.kernel, Neeraj Kumar
CXL region information preserved from the LSA needs to be exported for
use by the CXL driver for CXL region re-creation.
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Neeraj Kumar <s.neeraj@samsung.com>
---
drivers/nvdimm/dimm_devs.c | 12 ++++++++++++
include/linux/libnvdimm.h | 2 ++
2 files changed, 14 insertions(+)
diff --git a/drivers/nvdimm/dimm_devs.c b/drivers/nvdimm/dimm_devs.c
index 3363a97cc5b5..e1c95da92fbf 100644
--- a/drivers/nvdimm/dimm_devs.c
+++ b/drivers/nvdimm/dimm_devs.c
@@ -280,6 +280,18 @@ void *nvdimm_provider_data(struct nvdimm *nvdimm)
}
EXPORT_SYMBOL_GPL(nvdimm_provider_data);
+bool nvdimm_has_cxl_region(struct nvdimm *nvdimm)
+{
+ return nvdimm->is_region_label;
+}
+EXPORT_SYMBOL_GPL(nvdimm_has_cxl_region);
+
+void *nvdimm_get_cxl_region_param(struct nvdimm *nvdimm)
+{
+ return &nvdimm->cxl_region_params;
+}
+EXPORT_SYMBOL_GPL(nvdimm_get_cxl_region_param);
+
static ssize_t commands_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
diff --git a/include/linux/libnvdimm.h b/include/linux/libnvdimm.h
index 07ea2e3f821a..3ffd50ab6ac4 100644
--- a/include/linux/libnvdimm.h
+++ b/include/linux/libnvdimm.h
@@ -330,6 +330,8 @@ int nvdimm_in_overwrite(struct nvdimm *nvdimm);
bool is_nvdimm_sync(struct nd_region *nd_region);
int nd_region_label_update(struct nd_region *nd_region);
int nd_region_label_delete(struct nd_region *nd_region);
+bool nvdimm_has_cxl_region(struct nvdimm *nvdimm);
+void *nvdimm_get_cxl_region_param(struct nvdimm *nvdimm);
static inline int nvdimm_ctl(struct nvdimm *nvdimm, unsigned int cmd, void *buf,
unsigned int buf_len, int *cmd_rc)
--
2.34.1
^ permalink raw reply related [flat|nested] 53+ messages in thread
* [PATCH V5 10/17] cxl/mem: Refactor cxl pmem region auto-assembling
2026-01-09 12:44 ` [PATCH V5 00/17] Add CXL LSA 2.1 format support in nvdimm and cxl pmem Neeraj Kumar
` (8 preceding siblings ...)
2026-01-09 12:44 ` [PATCH V5 09/17] nvdimm/label: Export routine to fetch region information Neeraj Kumar
@ 2026-01-09 12:44 ` Neeraj Kumar
2026-01-15 18:08 ` Jonathan Cameron
2026-01-09 12:44 ` [PATCH V5 11/17] cxl/region: Add devm_cxl_pmem_add_region() for pmem region creation Neeraj Kumar
` (7 subsequent siblings)
17 siblings, 1 reply; 53+ messages in thread
From: Neeraj Kumar @ 2026-01-09 12:44 UTC (permalink / raw)
To: linux-cxl, nvdimm, linux-kernel, gost.dev
Cc: a.manzanares, vishak.g, neeraj.kernel, Neeraj Kumar
In 84ec985944ef3, devm_cxl_add_nvdimm() sequence was changed and called
before devm_cxl_add_endpoint(). It's because cxl pmem region auto-assembly
used to get called at last in cxl_endpoint_port_probe(), which requires
cxl_nvd presence.
For cxl region persistency, region creation happens during nvdimm_probe
which need the completion of endpoint probe.
In order to accommodate both cxl pmem region auto-assembly and cxl region
persistency, refactored following
1. Re-Sequence devm_cxl_add_nvdimm() after devm_cxl_add_endpoint(). This
will be called only after successful completion of endpoint probe.
2. Create cxl_region_discovery() which performs pmem region
auto-assembly and remove cxl pmem region auto-assembly from
cxl_endpoint_port_probe()
3. Register cxl_region_discovery() with devm_cxl_add_memdev() which gets
called during cxl_pci_probe() in context of cxl_mem_probe()
4. As cxlmd->ops->probe() calls registered cxl_region_discovery(), so
move devm_cxl_add_nvdimm() before cxlmd->ops->probe(). It guarantees
both the completion of endpoint probe and cxl_nvd presence before
calling cxlmd->ops->probe().
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Neeraj Kumar <s.neeraj@samsung.com>
---
drivers/cxl/core/region.c | 37 +++++++++++++++++++++++++++++++++++++
drivers/cxl/cxl.h | 5 +++++
drivers/cxl/mem.c | 18 +++++++++---------
drivers/cxl/pci.c | 4 +++-
drivers/cxl/port.c | 39 +--------------------------------------
5 files changed, 55 insertions(+), 48 deletions(-)
diff --git a/drivers/cxl/core/region.c b/drivers/cxl/core/region.c
index ae899f68551f..26238fb5e8cf 100644
--- a/drivers/cxl/core/region.c
+++ b/drivers/cxl/core/region.c
@@ -3727,6 +3727,43 @@ int cxl_add_to_region(struct cxl_endpoint_decoder *cxled)
}
EXPORT_SYMBOL_NS_GPL(cxl_add_to_region, "CXL");
+static int discover_region(struct device *dev, void *unused)
+{
+ struct cxl_endpoint_decoder *cxled;
+ int rc;
+
+ if (!is_endpoint_decoder(dev))
+ return 0;
+
+ cxled = to_cxl_endpoint_decoder(dev);
+ if ((cxled->cxld.flags & CXL_DECODER_F_ENABLE) == 0)
+ return 0;
+
+ if (cxled->state != CXL_DECODER_STATE_AUTO)
+ return 0;
+
+ /*
+ * Region enumeration is opportunistic, if this add-event fails,
+ * continue to the next endpoint decoder.
+ */
+ rc = cxl_add_to_region(cxled);
+ if (rc)
+ dev_dbg(dev, "failed to add to region: %#llx-%#llx\n",
+ cxled->cxld.hpa_range.start, cxled->cxld.hpa_range.end);
+
+ return 0;
+}
+
+int cxl_region_discovery(struct cxl_memdev *cxlmd)
+{
+ struct cxl_port *port = cxlmd->endpoint;
+
+ device_for_each_child(&port->dev, NULL, discover_region);
+
+ return 0;
+}
+EXPORT_SYMBOL_NS_GPL(cxl_region_discovery, "CXL");
+
u64 cxl_port_get_spa_cache_alias(struct cxl_port *endpoint, u64 spa)
{
struct cxl_region_ref *iter;
diff --git a/drivers/cxl/cxl.h b/drivers/cxl/cxl.h
index ba17fa86d249..684a0d1b441a 100644
--- a/drivers/cxl/cxl.h
+++ b/drivers/cxl/cxl.h
@@ -904,6 +904,7 @@ struct cxl_pmem_region *to_cxl_pmem_region(struct device *dev);
int cxl_add_to_region(struct cxl_endpoint_decoder *cxled);
struct cxl_dax_region *to_cxl_dax_region(struct device *dev);
u64 cxl_port_get_spa_cache_alias(struct cxl_port *endpoint, u64 spa);
+int cxl_region_discovery(struct cxl_memdev *cxlmd);
#else
static inline bool is_cxl_pmem_region(struct device *dev)
{
@@ -926,6 +927,10 @@ static inline u64 cxl_port_get_spa_cache_alias(struct cxl_port *endpoint,
{
return 0;
}
+static inline int cxl_region_discovery(struct cxl_memdev *cxlmd)
+{
+ return 0;
+}
#endif
void cxl_endpoint_parse_cdat(struct cxl_port *port);
diff --git a/drivers/cxl/mem.c b/drivers/cxl/mem.c
index 13d9e089ecaf..f5e3e2fca86c 100644
--- a/drivers/cxl/mem.c
+++ b/drivers/cxl/mem.c
@@ -115,15 +115,6 @@ static int cxl_mem_probe(struct device *dev)
return -ENXIO;
}
- if (cxl_pmem_size(cxlds) && IS_ENABLED(CONFIG_CXL_PMEM)) {
- rc = devm_cxl_add_nvdimm(parent_port, cxlmd);
- if (rc) {
- if (rc == -ENODEV)
- dev_info(dev, "PMEM disabled by platform\n");
- return rc;
- }
- }
-
if (dport->rch)
endpoint_parent = parent_port->uport_dev;
else
@@ -143,6 +134,15 @@ static int cxl_mem_probe(struct device *dev)
return rc;
}
+ if (cxl_pmem_size(cxlds) && IS_ENABLED(CONFIG_CXL_PMEM)) {
+ rc = devm_cxl_add_nvdimm(parent_port, cxlmd);
+ if (rc) {
+ if (rc == -ENODEV)
+ dev_info(dev, "PMEM disabled by platform\n");
+ return rc;
+ }
+ }
+
if (cxlmd->ops) {
rc = cxlmd->ops->probe(cxlmd);
if (rc)
diff --git a/drivers/cxl/pci.c b/drivers/cxl/pci.c
index e21051d79b25..d56fdfe4b43b 100644
--- a/drivers/cxl/pci.c
+++ b/drivers/cxl/pci.c
@@ -907,6 +907,7 @@ static int cxl_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
struct cxl_memdev_state *mds;
struct cxl_dev_state *cxlds;
struct cxl_register_map map;
+ struct cxl_memdev_ops ops;
struct cxl_memdev *cxlmd;
int rc, pmu_count;
unsigned int i;
@@ -1006,7 +1007,8 @@ static int cxl_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
if (rc)
dev_dbg(&pdev->dev, "No CXL Features discovered\n");
- cxlmd = devm_cxl_add_memdev(&pdev->dev, cxlds, NULL);
+ ops.probe = cxl_region_discovery;
+ cxlmd = devm_cxl_add_memdev(&pdev->dev, cxlds, &ops);
if (IS_ERR(cxlmd))
return PTR_ERR(cxlmd);
diff --git a/drivers/cxl/port.c b/drivers/cxl/port.c
index d5fd0c5ae49b..ad98b2881fed 100644
--- a/drivers/cxl/port.c
+++ b/drivers/cxl/port.c
@@ -31,33 +31,6 @@ static void schedule_detach(void *cxlmd)
schedule_cxl_memdev_detach(cxlmd);
}
-static int discover_region(struct device *dev, void *unused)
-{
- struct cxl_endpoint_decoder *cxled;
- int rc;
-
- if (!is_endpoint_decoder(dev))
- return 0;
-
- cxled = to_cxl_endpoint_decoder(dev);
- if ((cxled->cxld.flags & CXL_DECODER_F_ENABLE) == 0)
- return 0;
-
- if (cxled->state != CXL_DECODER_STATE_AUTO)
- return 0;
-
- /*
- * Region enumeration is opportunistic, if this add-event fails,
- * continue to the next endpoint decoder.
- */
- rc = cxl_add_to_region(cxled);
- if (rc)
- dev_dbg(dev, "failed to add to region: %#llx-%#llx\n",
- cxled->cxld.hpa_range.start, cxled->cxld.hpa_range.end);
-
- return 0;
-}
-
static int cxl_switch_port_probe(struct cxl_port *port)
{
/* Reset nr_dports for rebind of driver */
@@ -83,17 +56,7 @@ static int cxl_endpoint_port_probe(struct cxl_port *port)
if (rc)
return rc;
- rc = devm_cxl_endpoint_decoders_setup(port);
- if (rc)
- return rc;
-
- /*
- * Now that all endpoint decoders are successfully enumerated, try to
- * assemble regions from committed decoders
- */
- device_for_each_child(&port->dev, NULL, discover_region);
-
- return 0;
+ return devm_cxl_endpoint_decoders_setup(port);
}
static int cxl_port_probe(struct device *dev)
--
2.34.1
^ permalink raw reply related [flat|nested] 53+ messages in thread
* [PATCH V5 11/17] cxl/region: Add devm_cxl_pmem_add_region() for pmem region creation
2026-01-09 12:44 ` [PATCH V5 00/17] Add CXL LSA 2.1 format support in nvdimm and cxl pmem Neeraj Kumar
` (9 preceding siblings ...)
2026-01-09 12:44 ` [PATCH V5 10/17] cxl/mem: Refactor cxl pmem region auto-assembling Neeraj Kumar
@ 2026-01-09 12:44 ` Neeraj Kumar
2026-01-15 18:17 ` Jonathan Cameron
2026-01-09 12:44 ` [PATCH V5 12/17] cxl/pmem: Preserve region information into nd_set Neeraj Kumar
` (6 subsequent siblings)
17 siblings, 1 reply; 53+ messages in thread
From: Neeraj Kumar @ 2026-01-09 12:44 UTC (permalink / raw)
To: linux-cxl, nvdimm, linux-kernel, gost.dev
Cc: a.manzanares, vishak.g, neeraj.kernel, Neeraj Kumar
devm_cxl_pmem_add_region() is used to create cxl region based on region
information scanned from LSA.
devm_cxl_add_region() is used to just allocate cxlr and its fields are
filled later by userspace tool using device attributes (*_store()).
Inspiration for devm_cxl_pmem_add_region() is taken from these device
attributes (_store*) calls. It allocates cxlr and fills information
parsed from LSA and calls device_add(&cxlr->dev) to initiate further
region creation porbes
Rename __create_region() to cxl_create_region(), which will be used
in later patch to create cxl region after fetching region information
from LSA.
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Neeraj Kumar <s.neeraj@samsung.com>
---
drivers/cxl/core/core.h | 12 ++++
drivers/cxl/core/region.c | 137 ++++++++++++++++++++++++++++++++++++--
2 files changed, 144 insertions(+), 5 deletions(-)
diff --git a/drivers/cxl/core/core.h b/drivers/cxl/core/core.h
index 1fb66132b777..268f6d19ab9d 100644
--- a/drivers/cxl/core/core.h
+++ b/drivers/cxl/core/core.h
@@ -42,6 +42,10 @@ int cxl_get_poison_by_endpoint(struct cxl_port *port);
struct cxl_region *cxl_dpa_to_region(const struct cxl_memdev *cxlmd, u64 dpa);
u64 cxl_dpa_to_hpa(struct cxl_region *cxlr, const struct cxl_memdev *cxlmd,
u64 dpa);
+struct cxl_region *cxl_create_region(struct cxl_root_decoder *cxlrd,
+ enum cxl_partition_mode mode, int id,
+ struct cxl_pmem_region_params *pmem_params,
+ struct cxl_endpoint_decoder *cxled);
#else
static inline u64 cxl_dpa_to_hpa(struct cxl_region *cxlr,
@@ -71,6 +75,14 @@ static inline int cxl_region_init(void)
static inline void cxl_region_exit(void)
{
}
+static inline struct cxl_region *
+cxl_create_region(struct cxl_root_decoder *cxlrd,
+ enum cxl_partition_mode mode, int id,
+ struct cxl_pmem_region_params *params,
+ struct cxl_endpoint_decoder *cxled)
+{
+ return ERR_PTR(-EOPNOTSUPP);
+}
#define CXL_REGION_ATTR(x) NULL
#define CXL_REGION_TYPE(x) NULL
#define SET_CXL_REGION_ATTR(x)
diff --git a/drivers/cxl/core/region.c b/drivers/cxl/core/region.c
index 26238fb5e8cf..13779aeacd8e 100644
--- a/drivers/cxl/core/region.c
+++ b/drivers/cxl/core/region.c
@@ -2621,6 +2621,127 @@ static struct cxl_region *devm_cxl_add_region(struct cxl_root_decoder *cxlrd,
return ERR_PTR(rc);
}
+static ssize_t alloc_region_hpa(struct cxl_region *cxlr, u64 size)
+{
+ int rc;
+
+ if (!size)
+ return -EINVAL;
+
+ ACQUIRE(rwsem_write_kill, rwsem)(&cxl_rwsem.region);
+ if ((rc = ACQUIRE_ERR(rwsem_write_kill, &rwsem)))
+ return rc;
+
+ return alloc_hpa(cxlr, size);
+}
+
+static ssize_t alloc_region_dpa(struct cxl_endpoint_decoder *cxled, u64 size)
+{
+ int rc;
+
+ if (!size)
+ return -EINVAL;
+
+ if (!IS_ALIGNED(size, SZ_256M))
+ return -EINVAL;
+
+ rc = cxl_dpa_free(cxled);
+ if (rc)
+ return rc;
+
+ return cxl_dpa_alloc(cxled, size);
+}
+
+static struct cxl_region *
+cxl_pmem_region_prep(struct cxl_root_decoder *cxlrd, int id,
+ struct cxl_pmem_region_params *params,
+ struct cxl_endpoint_decoder *cxled,
+ enum cxl_decoder_type type)
+{
+ struct cxl_region_params *p;
+ struct device *dev;
+ int rc;
+
+ struct cxl_region *cxlr __free(put_cxl_region) =
+ cxl_region_alloc(cxlrd, id);
+ if (IS_ERR(cxlr))
+ return cxlr;
+
+ dev = &cxlr->dev;
+ rc = dev_set_name(dev, "region%d", id);
+ if (rc)
+ return ERR_PTR(rc);
+
+ cxlr->mode = CXL_PARTMODE_PMEM;
+ cxlr->type = type;
+
+ p = &cxlr->params;
+ p->uuid = params->uuid;
+ p->interleave_ways = params->nlabel;
+ p->interleave_granularity = params->ig;
+
+ rc = alloc_region_hpa(cxlr, params->rawsize);
+ if (rc)
+ return ERR_PTR(rc);
+
+ rc = cxl_dpa_set_part(cxled, CXL_PARTMODE_PMEM);
+ if (rc)
+ return ERR_PTR(rc);
+
+ rc = alloc_region_dpa(cxled, params->rawsize);
+ if (rc)
+ return ERR_PTR(rc);
+
+ /*
+ * TODO: Currently we have support of interleave_way == 1, where
+ * we can only have one region per mem device. It means mem device
+ * position (params->position) will always be 0. It is therefore
+ * attaching only one target at params->position
+ */
+ if (params->position)
+ return ERR_PTR(-EOPNOTSUPP);
+
+ rc = attach_target(cxlr, cxled, params->position, TASK_INTERRUPTIBLE);
+ if (rc)
+ return ERR_PTR(rc);
+
+ rc = __commit(cxlr);
+ if (rc)
+ return ERR_PTR(rc);
+
+ rc = device_add(dev);
+ if (rc)
+ return ERR_PTR(rc);
+
+ return no_free_ptr(cxlr);
+}
+
+static struct cxl_region *
+devm_cxl_pmem_add_region(struct cxl_root_decoder *cxlrd, int id,
+ struct cxl_pmem_region_params *params,
+ struct cxl_endpoint_decoder *cxled,
+ enum cxl_decoder_type type)
+{
+ struct cxl_port *root_port;
+ struct cxl_region *cxlr;
+ int rc;
+
+ cxlr = cxl_pmem_region_prep(cxlrd, id, params, cxled, type);
+ if (IS_ERR(cxlr))
+ return cxlr;
+
+ root_port = to_cxl_port(cxlrd->cxlsd.cxld.dev.parent);
+ rc = devm_add_action_or_reset(root_port->uport_dev,
+ unregister_region, cxlr);
+ if (rc)
+ return ERR_PTR(rc);
+
+ dev_dbg(root_port->uport_dev, "%s: created %s\n",
+ dev_name(&cxlrd->cxlsd.cxld.dev), dev_name(&cxlr->dev));
+
+ return cxlr;
+}
+
static ssize_t __create_region_show(struct cxl_root_decoder *cxlrd, char *buf)
{
return sysfs_emit(buf, "region%u\n", atomic_read(&cxlrd->region_id));
@@ -2638,8 +2759,10 @@ static ssize_t create_ram_region_show(struct device *dev,
return __create_region_show(to_cxl_root_decoder(dev), buf);
}
-static struct cxl_region *__create_region(struct cxl_root_decoder *cxlrd,
- enum cxl_partition_mode mode, int id)
+struct cxl_region *cxl_create_region(struct cxl_root_decoder *cxlrd,
+ enum cxl_partition_mode mode, int id,
+ struct cxl_pmem_region_params *pmem_params,
+ struct cxl_endpoint_decoder *cxled)
{
int rc;
@@ -2661,6 +2784,9 @@ static struct cxl_region *__create_region(struct cxl_root_decoder *cxlrd,
return ERR_PTR(-EBUSY);
}
+ if (pmem_params)
+ return devm_cxl_pmem_add_region(cxlrd, id, pmem_params, cxled,
+ CXL_DECODER_HOSTONLYMEM);
return devm_cxl_add_region(cxlrd, id, mode, CXL_DECODER_HOSTONLYMEM);
}
@@ -2675,7 +2801,7 @@ static ssize_t create_region_store(struct device *dev, const char *buf,
if (rc != 1)
return -EINVAL;
- cxlr = __create_region(cxlrd, mode, id);
+ cxlr = cxl_create_region(cxlrd, mode, id, NULL, NULL);
if (IS_ERR(cxlr))
return PTR_ERR(cxlr);
@@ -3644,8 +3770,9 @@ static struct cxl_region *construct_region(struct cxl_root_decoder *cxlrd,
struct cxl_region *cxlr;
do {
- cxlr = __create_region(cxlrd, cxlds->part[part].mode,
- atomic_read(&cxlrd->region_id));
+ cxlr = cxl_create_region(cxlrd, cxlds->part[part].mode,
+ atomic_read(&cxlrd->region_id),
+ NULL, NULL);
} while (IS_ERR(cxlr) && PTR_ERR(cxlr) == -EBUSY);
if (IS_ERR(cxlr)) {
--
2.34.1
^ permalink raw reply related [flat|nested] 53+ messages in thread
* [PATCH V5 12/17] cxl/pmem: Preserve region information into nd_set
2026-01-09 12:44 ` [PATCH V5 00/17] Add CXL LSA 2.1 format support in nvdimm and cxl pmem Neeraj Kumar
` (10 preceding siblings ...)
2026-01-09 12:44 ` [PATCH V5 11/17] cxl/region: Add devm_cxl_pmem_add_region() for pmem region creation Neeraj Kumar
@ 2026-01-09 12:44 ` Neeraj Kumar
2026-01-15 18:18 ` Jonathan Cameron
2026-01-09 12:44 ` [PATCH V5 13/17] cxl/pmem_region: Prep patch to accommodate pmem_region attributes Neeraj Kumar
` (5 subsequent siblings)
17 siblings, 1 reply; 53+ messages in thread
From: Neeraj Kumar @ 2026-01-09 12:44 UTC (permalink / raw)
To: linux-cxl, nvdimm, linux-kernel, gost.dev
Cc: a.manzanares, vishak.g, neeraj.kernel, Neeraj Kumar
Save region information stored in cxlr to nd_set during
cxl_pmem_region_probe in nd_set. This saved region information is being
stored into LSA, which will be used for cxl region persistence
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Neeraj Kumar <s.neeraj@samsung.com>
---
drivers/cxl/pmem.c | 13 +++++++------
1 file changed, 7 insertions(+), 6 deletions(-)
diff --git a/drivers/cxl/pmem.c b/drivers/cxl/pmem.c
index e197883690ef..a6eba3572090 100644
--- a/drivers/cxl/pmem.c
+++ b/drivers/cxl/pmem.c
@@ -377,6 +377,7 @@ static int cxl_pmem_region_probe(struct device *dev)
struct nd_mapping_desc mappings[CXL_DECODER_MAX_INTERLEAVE];
struct cxl_pmem_region *cxlr_pmem = to_cxl_pmem_region(dev);
struct cxl_region *cxlr = cxlr_pmem->cxlr;
+ struct cxl_region_params *p = &cxlr->params;
struct cxl_nvdimm_bridge *cxl_nvb = cxlr->cxl_nvb;
struct cxl_pmem_region_info *info = NULL;
struct nd_interleave_set *nd_set;
@@ -465,12 +466,12 @@ static int cxl_pmem_region_probe(struct device *dev)
ndr_desc.num_mappings = cxlr_pmem->nr_mappings;
ndr_desc.mapping = mappings;
- /*
- * TODO enable CXL labels which skip the need for 'interleave-set cookie'
- */
- nd_set->cookie1 =
- nd_fletcher64(info, sizeof(*info) * cxlr_pmem->nr_mappings, 0);
- nd_set->cookie2 = nd_set->cookie1;
+ nd_set->uuid = p->uuid;
+ nd_set->interleave_ways = p->interleave_ways;
+ nd_set->interleave_granularity = p->interleave_granularity;
+ nd_set->res = p->res;
+ nd_set->nr_targets = p->nr_targets;
+
ndr_desc.nd_set = nd_set;
cxlr_pmem->nd_region =
--
2.34.1
^ permalink raw reply related [flat|nested] 53+ messages in thread
* [PATCH V5 13/17] cxl/pmem_region: Prep patch to accommodate pmem_region attributes
2026-01-09 12:44 ` [PATCH V5 00/17] Add CXL LSA 2.1 format support in nvdimm and cxl pmem Neeraj Kumar
` (11 preceding siblings ...)
2026-01-09 12:44 ` [PATCH V5 12/17] cxl/pmem: Preserve region information into nd_set Neeraj Kumar
@ 2026-01-09 12:44 ` Neeraj Kumar
2026-01-09 12:44 ` [PATCH V5 14/17] cxl/pmem_region: Introduce CONFIG_CXL_PMEM_REGION for core/pmem_region.c Neeraj Kumar
` (4 subsequent siblings)
17 siblings, 0 replies; 53+ messages in thread
From: Neeraj Kumar @ 2026-01-09 12:44 UTC (permalink / raw)
To: linux-cxl, nvdimm, linux-kernel, gost.dev
Cc: a.manzanares, vishak.g, neeraj.kernel, Neeraj Kumar
For region label update, need to create device attribute, which calls
nvdimm exported routine thus making pmem_region dependent on libnvdimm.
Because of this dependency of pmem region on libnvdimm, segregate pmem
region related code from core/region.c to core/pmem_region.c
This patch has no functionality change. Its just code movement from
core/region.c to core/pmem_region.c
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>
Signed-off-by: Neeraj Kumar <s.neeraj@samsung.com>
---
drivers/cxl/core/Makefile | 2 +-
drivers/cxl/core/core.h | 10 ++
drivers/cxl/core/pmem_region.c | 201 +++++++++++++++++++++++++++++++++
drivers/cxl/core/region.c | 188 +-----------------------------
tools/testing/cxl/Kbuild | 2 +-
5 files changed, 214 insertions(+), 189 deletions(-)
create mode 100644 drivers/cxl/core/pmem_region.c
diff --git a/drivers/cxl/core/Makefile b/drivers/cxl/core/Makefile
index 5ad8fef210b5..fe0fcab6d730 100644
--- a/drivers/cxl/core/Makefile
+++ b/drivers/cxl/core/Makefile
@@ -16,7 +16,7 @@ cxl_core-y += pmu.o
cxl_core-y += cdat.o
cxl_core-y += ras.o
cxl_core-$(CONFIG_TRACING) += trace.o
-cxl_core-$(CONFIG_CXL_REGION) += region.o
+cxl_core-$(CONFIG_CXL_REGION) += region.o pmem_region.o
cxl_core-$(CONFIG_CXL_MCE) += mce.o
cxl_core-$(CONFIG_CXL_FEATURES) += features.o
cxl_core-$(CONFIG_CXL_EDAC_MEM_FEATURES) += edac.o
diff --git a/drivers/cxl/core/core.h b/drivers/cxl/core/core.h
index 268f6d19ab9d..4eed243c0d7d 100644
--- a/drivers/cxl/core/core.h
+++ b/drivers/cxl/core/core.h
@@ -46,6 +46,8 @@ struct cxl_region *cxl_create_region(struct cxl_root_decoder *cxlrd,
enum cxl_partition_mode mode, int id,
struct cxl_pmem_region_params *pmem_params,
struct cxl_endpoint_decoder *cxled);
+struct cxl_region *to_cxl_region(struct device *dev);
+int devm_cxl_add_pmem_region(struct cxl_region *cxlr);
#else
static inline u64 cxl_dpa_to_hpa(struct cxl_region *cxlr,
@@ -83,6 +85,14 @@ cxl_create_region(struct cxl_root_decoder *cxlrd,
{
return ERR_PTR(-EOPNOTSUPP);
}
+static inline struct cxl_region *to_cxl_region(struct device *dev)
+{
+ return NULL;
+}
+static inline int devm_cxl_add_pmem_region(struct cxl_region *cxlr)
+{
+ return 0;
+}
#define CXL_REGION_ATTR(x) NULL
#define CXL_REGION_TYPE(x) NULL
#define SET_CXL_REGION_ATTR(x)
diff --git a/drivers/cxl/core/pmem_region.c b/drivers/cxl/core/pmem_region.c
new file mode 100644
index 000000000000..dcaab59108fd
--- /dev/null
+++ b/drivers/cxl/core/pmem_region.c
@@ -0,0 +1,201 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/* Copyright(c) 2020 Intel Corporation. */
+#include <linux/device.h>
+#include <linux/memregion.h>
+#include <cxlmem.h>
+#include <cxl.h>
+#include "core.h"
+
+/**
+ * DOC: cxl pmem region
+ *
+ * The core CXL PMEM region infrastructure supports persistent memory
+ * region creation using LIBNVDIMM subsystem. It has dependency on
+ * LIBNVDIMM, pmem region needs to update the cxl region information
+ * in the LSA.
+ */
+
+static void cxl_pmem_region_release(struct device *dev)
+{
+ struct cxl_pmem_region *cxlr_pmem = to_cxl_pmem_region(dev);
+ int i;
+
+ for (i = 0; i < cxlr_pmem->nr_mappings; i++) {
+ struct cxl_memdev *cxlmd = cxlr_pmem->mapping[i].cxlmd;
+
+ put_device(&cxlmd->dev);
+ }
+
+ kfree(cxlr_pmem);
+}
+
+static const struct attribute_group *cxl_pmem_region_attribute_groups[] = {
+ &cxl_base_attribute_group,
+ NULL
+};
+
+const struct device_type cxl_pmem_region_type = {
+ .name = "cxl_pmem_region",
+ .release = cxl_pmem_region_release,
+ .groups = cxl_pmem_region_attribute_groups,
+};
+
+bool is_cxl_pmem_region(struct device *dev)
+{
+ return dev->type == &cxl_pmem_region_type;
+}
+EXPORT_SYMBOL_NS_GPL(is_cxl_pmem_region, "CXL");
+
+struct cxl_pmem_region *to_cxl_pmem_region(struct device *dev)
+{
+ if (dev_WARN_ONCE(dev, !is_cxl_pmem_region(dev),
+ "not a cxl_pmem_region device\n"))
+ return NULL;
+ return container_of(dev, struct cxl_pmem_region, dev);
+}
+EXPORT_SYMBOL_NS_GPL(to_cxl_pmem_region, "CXL");
+
+static struct lock_class_key cxl_pmem_region_key;
+
+static int cxl_pmem_region_alloc(struct cxl_region *cxlr)
+{
+ struct cxl_region_params *p = &cxlr->params;
+ struct cxl_nvdimm_bridge *cxl_nvb;
+ struct device *dev;
+ int i;
+
+ guard(rwsem_read)(&cxl_rwsem.region);
+ if (p->state != CXL_CONFIG_COMMIT)
+ return -ENXIO;
+
+ struct cxl_pmem_region *cxlr_pmem __free(kfree) =
+ kzalloc(struct_size(cxlr_pmem, mapping, p->nr_targets),
+ GFP_KERNEL);
+ if (!cxlr_pmem)
+ return -ENOMEM;
+
+ cxlr_pmem->hpa_range.start = p->res->start;
+ cxlr_pmem->hpa_range.end = p->res->end;
+
+ /* Snapshot the region configuration underneath the cxl_region_rwsem */
+ cxlr_pmem->nr_mappings = p->nr_targets;
+ for (i = 0; i < p->nr_targets; i++) {
+ struct cxl_endpoint_decoder *cxled = p->targets[i];
+ struct cxl_memdev *cxlmd = cxled_to_memdev(cxled);
+ struct cxl_pmem_region_mapping *m = &cxlr_pmem->mapping[i];
+
+ /*
+ * Regions never span CXL root devices, so by definition the
+ * bridge for one device is the same for all.
+ */
+ if (i == 0) {
+ cxl_nvb = cxl_find_nvdimm_bridge(cxlmd->endpoint);
+ if (!cxl_nvb)
+ return -ENODEV;
+ cxlr->cxl_nvb = cxl_nvb;
+ }
+ m->cxlmd = cxlmd;
+ get_device(&cxlmd->dev);
+ m->start = cxled->dpa_res->start;
+ m->size = resource_size(cxled->dpa_res);
+ m->position = i;
+ }
+
+ dev = &cxlr_pmem->dev;
+ device_initialize(dev);
+ lockdep_set_class(&dev->mutex, &cxl_pmem_region_key);
+ device_set_pm_not_required(dev);
+ dev->parent = &cxlr->dev;
+ dev->bus = &cxl_bus_type;
+ dev->type = &cxl_pmem_region_type;
+ cxlr_pmem->cxlr = cxlr;
+ cxlr->cxlr_pmem = no_free_ptr(cxlr_pmem);
+
+ return 0;
+}
+
+static void cxlr_pmem_unregister(void *_cxlr_pmem)
+{
+ struct cxl_pmem_region *cxlr_pmem = _cxlr_pmem;
+ struct cxl_region *cxlr = cxlr_pmem->cxlr;
+ struct cxl_nvdimm_bridge *cxl_nvb = cxlr->cxl_nvb;
+
+ /*
+ * Either the bridge is in ->remove() context under the device_lock(),
+ * or cxlr_release_nvdimm() is cancelling the bridge's release action
+ * for @cxlr_pmem and doing it itself (while manually holding the bridge
+ * lock).
+ */
+ device_lock_assert(&cxl_nvb->dev);
+ cxlr->cxlr_pmem = NULL;
+ cxlr_pmem->cxlr = NULL;
+ device_unregister(&cxlr_pmem->dev);
+}
+
+static void cxlr_release_nvdimm(void *_cxlr)
+{
+ struct cxl_region *cxlr = _cxlr;
+ struct cxl_nvdimm_bridge *cxl_nvb = cxlr->cxl_nvb;
+
+ scoped_guard(device, &cxl_nvb->dev) {
+ if (cxlr->cxlr_pmem)
+ devm_release_action(&cxl_nvb->dev, cxlr_pmem_unregister,
+ cxlr->cxlr_pmem);
+ }
+ cxlr->cxl_nvb = NULL;
+ put_device(&cxl_nvb->dev);
+}
+
+/**
+ * devm_cxl_add_pmem_region() - add a cxl_region-to-nd_region bridge
+ * @cxlr: parent CXL region for this pmem region bridge device
+ *
+ * Return: 0 on success negative error code on failure.
+ */
+int devm_cxl_add_pmem_region(struct cxl_region *cxlr)
+{
+ struct cxl_pmem_region *cxlr_pmem;
+ struct cxl_nvdimm_bridge *cxl_nvb;
+ struct device *dev;
+ int rc;
+
+ rc = cxl_pmem_region_alloc(cxlr);
+ if (rc)
+ return rc;
+ cxlr_pmem = cxlr->cxlr_pmem;
+ cxl_nvb = cxlr->cxl_nvb;
+
+ dev = &cxlr_pmem->dev;
+ rc = dev_set_name(dev, "pmem_region%d", cxlr->id);
+ if (rc)
+ goto err;
+
+ rc = device_add(dev);
+ if (rc)
+ goto err;
+
+ dev_dbg(&cxlr->dev, "%s: register %s\n", dev_name(dev->parent),
+ dev_name(dev));
+
+ scoped_guard(device, &cxl_nvb->dev) {
+ if (cxl_nvb->dev.driver)
+ rc = devm_add_action_or_reset(&cxl_nvb->dev,
+ cxlr_pmem_unregister,
+ cxlr_pmem);
+ else
+ rc = -ENXIO;
+ }
+
+ if (rc)
+ goto err_bridge;
+
+ /* @cxlr carries a reference on @cxl_nvb until cxlr_release_nvdimm */
+ return devm_add_action_or_reset(&cxlr->dev, cxlr_release_nvdimm, cxlr);
+
+err:
+ put_device(dev);
+err_bridge:
+ put_device(&cxl_nvb->dev);
+ cxlr->cxl_nvb = NULL;
+ return rc;
+}
diff --git a/drivers/cxl/core/region.c b/drivers/cxl/core/region.c
index 13779aeacd8e..9a86d1c467b2 100644
--- a/drivers/cxl/core/region.c
+++ b/drivers/cxl/core/region.c
@@ -38,8 +38,6 @@
*/
static nodemask_t nodemask_region_seen = NODE_MASK_NONE;
-static struct cxl_region *to_cxl_region(struct device *dev);
-
#define __ACCESS_ATTR_RO(_level, _name) { \
.attr = { .name = __stringify(_name), .mode = 0444 }, \
.show = _name##_access##_level##_show, \
@@ -2429,7 +2427,7 @@ bool is_cxl_region(struct device *dev)
}
EXPORT_SYMBOL_NS_GPL(is_cxl_region, "CXL");
-static struct cxl_region *to_cxl_region(struct device *dev)
+struct cxl_region *to_cxl_region(struct device *dev)
{
if (dev_WARN_ONCE(dev, dev->type != &cxl_region_type,
"not a cxl_region device\n"))
@@ -2872,46 +2870,6 @@ static ssize_t delete_region_store(struct device *dev,
}
DEVICE_ATTR_WO(delete_region);
-static void cxl_pmem_region_release(struct device *dev)
-{
- struct cxl_pmem_region *cxlr_pmem = to_cxl_pmem_region(dev);
- int i;
-
- for (i = 0; i < cxlr_pmem->nr_mappings; i++) {
- struct cxl_memdev *cxlmd = cxlr_pmem->mapping[i].cxlmd;
-
- put_device(&cxlmd->dev);
- }
-
- kfree(cxlr_pmem);
-}
-
-static const struct attribute_group *cxl_pmem_region_attribute_groups[] = {
- &cxl_base_attribute_group,
- NULL,
-};
-
-const struct device_type cxl_pmem_region_type = {
- .name = "cxl_pmem_region",
- .release = cxl_pmem_region_release,
- .groups = cxl_pmem_region_attribute_groups,
-};
-
-bool is_cxl_pmem_region(struct device *dev)
-{
- return dev->type == &cxl_pmem_region_type;
-}
-EXPORT_SYMBOL_NS_GPL(is_cxl_pmem_region, "CXL");
-
-struct cxl_pmem_region *to_cxl_pmem_region(struct device *dev)
-{
- if (dev_WARN_ONCE(dev, !is_cxl_pmem_region(dev),
- "not a cxl_pmem_region device\n"))
- return NULL;
- return container_of(dev, struct cxl_pmem_region, dev);
-}
-EXPORT_SYMBOL_NS_GPL(to_cxl_pmem_region, "CXL");
-
struct cxl_poison_context {
struct cxl_port *port;
int part;
@@ -3343,64 +3301,6 @@ static int region_offset_to_dpa_result(struct cxl_region *cxlr, u64 offset,
return -ENXIO;
}
-static struct lock_class_key cxl_pmem_region_key;
-
-static int cxl_pmem_region_alloc(struct cxl_region *cxlr)
-{
- struct cxl_region_params *p = &cxlr->params;
- struct cxl_nvdimm_bridge *cxl_nvb;
- struct device *dev;
- int i;
-
- guard(rwsem_read)(&cxl_rwsem.region);
- if (p->state != CXL_CONFIG_COMMIT)
- return -ENXIO;
-
- struct cxl_pmem_region *cxlr_pmem __free(kfree) =
- kzalloc(struct_size(cxlr_pmem, mapping, p->nr_targets), GFP_KERNEL);
- if (!cxlr_pmem)
- return -ENOMEM;
-
- cxlr_pmem->hpa_range.start = p->res->start;
- cxlr_pmem->hpa_range.end = p->res->end;
-
- /* Snapshot the region configuration underneath the cxl_rwsem.region */
- cxlr_pmem->nr_mappings = p->nr_targets;
- for (i = 0; i < p->nr_targets; i++) {
- struct cxl_endpoint_decoder *cxled = p->targets[i];
- struct cxl_memdev *cxlmd = cxled_to_memdev(cxled);
- struct cxl_pmem_region_mapping *m = &cxlr_pmem->mapping[i];
-
- /*
- * Regions never span CXL root devices, so by definition the
- * bridge for one device is the same for all.
- */
- if (i == 0) {
- cxl_nvb = cxl_find_nvdimm_bridge(cxlmd->endpoint);
- if (!cxl_nvb)
- return -ENODEV;
- cxlr->cxl_nvb = cxl_nvb;
- }
- m->cxlmd = cxlmd;
- get_device(&cxlmd->dev);
- m->start = cxled->dpa_res->start;
- m->size = resource_size(cxled->dpa_res);
- m->position = i;
- }
-
- dev = &cxlr_pmem->dev;
- device_initialize(dev);
- lockdep_set_class(&dev->mutex, &cxl_pmem_region_key);
- device_set_pm_not_required(dev);
- dev->parent = &cxlr->dev;
- dev->bus = &cxl_bus_type;
- dev->type = &cxl_pmem_region_type;
- cxlr_pmem->cxlr = cxlr;
- cxlr->cxlr_pmem = no_free_ptr(cxlr_pmem);
-
- return 0;
-}
-
static void cxl_dax_region_release(struct device *dev)
{
struct cxl_dax_region *cxlr_dax = to_cxl_dax_region(dev);
@@ -3464,92 +3364,6 @@ static struct cxl_dax_region *cxl_dax_region_alloc(struct cxl_region *cxlr)
return cxlr_dax;
}
-static void cxlr_pmem_unregister(void *_cxlr_pmem)
-{
- struct cxl_pmem_region *cxlr_pmem = _cxlr_pmem;
- struct cxl_region *cxlr = cxlr_pmem->cxlr;
- struct cxl_nvdimm_bridge *cxl_nvb = cxlr->cxl_nvb;
-
- /*
- * Either the bridge is in ->remove() context under the device_lock(),
- * or cxlr_release_nvdimm() is cancelling the bridge's release action
- * for @cxlr_pmem and doing it itself (while manually holding the bridge
- * lock).
- */
- device_lock_assert(&cxl_nvb->dev);
- cxlr->cxlr_pmem = NULL;
- cxlr_pmem->cxlr = NULL;
- device_unregister(&cxlr_pmem->dev);
-}
-
-static void cxlr_release_nvdimm(void *_cxlr)
-{
- struct cxl_region *cxlr = _cxlr;
- struct cxl_nvdimm_bridge *cxl_nvb = cxlr->cxl_nvb;
-
- scoped_guard(device, &cxl_nvb->dev) {
- if (cxlr->cxlr_pmem)
- devm_release_action(&cxl_nvb->dev, cxlr_pmem_unregister,
- cxlr->cxlr_pmem);
- }
- cxlr->cxl_nvb = NULL;
- put_device(&cxl_nvb->dev);
-}
-
-/**
- * devm_cxl_add_pmem_region() - add a cxl_region-to-nd_region bridge
- * @cxlr: parent CXL region for this pmem region bridge device
- *
- * Return: 0 on success negative error code on failure.
- */
-static int devm_cxl_add_pmem_region(struct cxl_region *cxlr)
-{
- struct cxl_pmem_region *cxlr_pmem;
- struct cxl_nvdimm_bridge *cxl_nvb;
- struct device *dev;
- int rc;
-
- rc = cxl_pmem_region_alloc(cxlr);
- if (rc)
- return rc;
- cxlr_pmem = cxlr->cxlr_pmem;
- cxl_nvb = cxlr->cxl_nvb;
-
- dev = &cxlr_pmem->dev;
- rc = dev_set_name(dev, "pmem_region%d", cxlr->id);
- if (rc)
- goto err;
-
- rc = device_add(dev);
- if (rc)
- goto err;
-
- dev_dbg(&cxlr->dev, "%s: register %s\n", dev_name(dev->parent),
- dev_name(dev));
-
- scoped_guard(device, &cxl_nvb->dev) {
- if (cxl_nvb->dev.driver)
- rc = devm_add_action_or_reset(&cxl_nvb->dev,
- cxlr_pmem_unregister,
- cxlr_pmem);
- else
- rc = -ENXIO;
- }
-
- if (rc)
- goto err_bridge;
-
- /* @cxlr carries a reference on @cxl_nvb until cxlr_release_nvdimm */
- return devm_add_action_or_reset(&cxlr->dev, cxlr_release_nvdimm, cxlr);
-
-err:
- put_device(dev);
-err_bridge:
- put_device(&cxl_nvb->dev);
- cxlr->cxl_nvb = NULL;
- return rc;
-}
-
static void cxlr_dax_unregister(void *_cxlr_dax)
{
struct cxl_dax_region *cxlr_dax = _cxlr_dax;
diff --git a/tools/testing/cxl/Kbuild b/tools/testing/cxl/Kbuild
index 0e151d0572d1..ad2496b38fdd 100644
--- a/tools/testing/cxl/Kbuild
+++ b/tools/testing/cxl/Kbuild
@@ -59,7 +59,7 @@ cxl_core-y += $(CXL_CORE_SRC)/pmu.o
cxl_core-y += $(CXL_CORE_SRC)/cdat.o
cxl_core-y += $(CXL_CORE_SRC)/ras.o
cxl_core-$(CONFIG_TRACING) += $(CXL_CORE_SRC)/trace.o
-cxl_core-$(CONFIG_CXL_REGION) += $(CXL_CORE_SRC)/region.o
+cxl_core-$(CONFIG_CXL_REGION) += $(CXL_CORE_SRC)/region.o $(CXL_CORE_SRC)/pmem_region.o
cxl_core-$(CONFIG_CXL_MCE) += $(CXL_CORE_SRC)/mce.o
cxl_core-$(CONFIG_CXL_FEATURES) += $(CXL_CORE_SRC)/features.o
cxl_core-$(CONFIG_CXL_EDAC_MEM_FEATURES) += $(CXL_CORE_SRC)/edac.o
--
2.34.1
^ permalink raw reply related [flat|nested] 53+ messages in thread
* [PATCH V5 14/17] cxl/pmem_region: Introduce CONFIG_CXL_PMEM_REGION for core/pmem_region.c
2026-01-09 12:44 ` [PATCH V5 00/17] Add CXL LSA 2.1 format support in nvdimm and cxl pmem Neeraj Kumar
` (12 preceding siblings ...)
2026-01-09 12:44 ` [PATCH V5 13/17] cxl/pmem_region: Prep patch to accommodate pmem_region attributes Neeraj Kumar
@ 2026-01-09 12:44 ` Neeraj Kumar
2026-01-15 18:19 ` Jonathan Cameron
2026-01-09 12:44 ` [PATCH V5 15/17] cxl/pmem_region: Add sysfs attribute cxl region label updation/deletion Neeraj Kumar
` (3 subsequent siblings)
17 siblings, 1 reply; 53+ messages in thread
From: Neeraj Kumar @ 2026-01-09 12:44 UTC (permalink / raw)
To: linux-cxl, nvdimm, linux-kernel, gost.dev
Cc: a.manzanares, vishak.g, neeraj.kernel, Neeraj Kumar
As pmem region label update/delete has hard dependency on libnvdimm.
It is therefore put core/pmem_region.c under CONFIG_CXL_PMEM_REGION
control. It handles the dependency by selecting CONFIG_LIBNVDIMM
if not enabled.
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Neeraj Kumar <s.neeraj@samsung.com>
---
drivers/cxl/Kconfig | 15 +++++++++++++++
drivers/cxl/core/Makefile | 3 ++-
drivers/cxl/core/core.h | 18 +++++++++++-------
drivers/cxl/cxl.h | 24 ++++++++++++++----------
tools/testing/cxl/Kbuild | 3 ++-
5 files changed, 44 insertions(+), 19 deletions(-)
diff --git a/drivers/cxl/Kconfig b/drivers/cxl/Kconfig
index f1361ed6a0d4..307fed8f1f56 100644
--- a/drivers/cxl/Kconfig
+++ b/drivers/cxl/Kconfig
@@ -211,6 +211,21 @@ config CXL_REGION
If unsure say 'y'
+config CXL_PMEM_REGION
+ bool "CXL: Pmem Region Support"
+ default CXL_BUS
+ depends on CXL_REGION
+ depends on ARCH_HAS_PMEM_API
+ depends on PHYS_ADDR_T_64BIT
+ depends on BLK_DEV
+ select LIBNVDIMM
+ help
+ Enable the CXL core to enumerate and provision CXL pmem regions.
+ A CXL pmem region need to update region label into LSA. For LSA
+ update/delete libnvdimm is required.
+
+ If unsure say 'y'
+
config CXL_REGION_INVALIDATION_TEST
bool "CXL: Region Cache Management Bypass (TEST)"
depends on CXL_REGION
diff --git a/drivers/cxl/core/Makefile b/drivers/cxl/core/Makefile
index fe0fcab6d730..399157beb917 100644
--- a/drivers/cxl/core/Makefile
+++ b/drivers/cxl/core/Makefile
@@ -16,7 +16,8 @@ cxl_core-y += pmu.o
cxl_core-y += cdat.o
cxl_core-y += ras.o
cxl_core-$(CONFIG_TRACING) += trace.o
-cxl_core-$(CONFIG_CXL_REGION) += region.o pmem_region.o
+cxl_core-$(CONFIG_CXL_REGION) += region.o
+cxl_core-$(CONFIG_CXL_PMEM_REGION) += pmem_region.o
cxl_core-$(CONFIG_CXL_MCE) += mce.o
cxl_core-$(CONFIG_CXL_FEATURES) += features.o
cxl_core-$(CONFIG_CXL_EDAC_MEM_FEATURES) += edac.o
diff --git a/drivers/cxl/core/core.h b/drivers/cxl/core/core.h
index 4eed243c0d7d..5ae693269771 100644
--- a/drivers/cxl/core/core.h
+++ b/drivers/cxl/core/core.h
@@ -34,7 +34,6 @@ int cxl_decoder_detach(struct cxl_region *cxlr,
#define CXL_REGION_ATTR(x) (&dev_attr_##x.attr)
#define CXL_REGION_TYPE(x) (&cxl_region_type)
#define SET_CXL_REGION_ATTR(x) (&dev_attr_##x.attr),
-#define CXL_PMEM_REGION_TYPE(x) (&cxl_pmem_region_type)
#define CXL_DAX_REGION_TYPE(x) (&cxl_dax_region_type)
int cxl_region_init(void);
void cxl_region_exit(void);
@@ -47,7 +46,6 @@ struct cxl_region *cxl_create_region(struct cxl_root_decoder *cxlrd,
struct cxl_pmem_region_params *pmem_params,
struct cxl_endpoint_decoder *cxled);
struct cxl_region *to_cxl_region(struct device *dev);
-int devm_cxl_add_pmem_region(struct cxl_region *cxlr);
#else
static inline u64 cxl_dpa_to_hpa(struct cxl_region *cxlr,
@@ -89,17 +87,23 @@ static inline struct cxl_region *to_cxl_region(struct device *dev)
{
return NULL;
}
-static inline int devm_cxl_add_pmem_region(struct cxl_region *cxlr)
-{
- return 0;
-}
#define CXL_REGION_ATTR(x) NULL
#define CXL_REGION_TYPE(x) NULL
#define SET_CXL_REGION_ATTR(x)
-#define CXL_PMEM_REGION_TYPE(x) NULL
#define CXL_DAX_REGION_TYPE(x) NULL
#endif
+#ifdef CONFIG_CXL_PMEM_REGION
+#define CXL_PMEM_REGION_TYPE(x) (&cxl_pmem_region_type)
+int devm_cxl_add_pmem_region(struct cxl_region *cxlr);
+#else
+#define CXL_PMEM_REGION_TYPE(x) NULL
+static inline int devm_cxl_add_pmem_region(struct cxl_region *cxlr)
+{
+ return -EINVAL;
+}
+#endif
+
struct cxl_send_command;
struct cxl_mem_query_commands;
int cxl_query_cmd(struct cxl_mailbox *cxl_mbox,
diff --git a/drivers/cxl/cxl.h b/drivers/cxl/cxl.h
index 684a0d1b441a..6ac3b40cb5ff 100644
--- a/drivers/cxl/cxl.h
+++ b/drivers/cxl/cxl.h
@@ -899,21 +899,11 @@ int devm_cxl_add_nvdimm(struct cxl_port *parent_port, struct cxl_memdev *cxlmd);
struct cxl_nvdimm_bridge *cxl_find_nvdimm_bridge(struct cxl_port *port);
#ifdef CONFIG_CXL_REGION
-bool is_cxl_pmem_region(struct device *dev);
-struct cxl_pmem_region *to_cxl_pmem_region(struct device *dev);
int cxl_add_to_region(struct cxl_endpoint_decoder *cxled);
struct cxl_dax_region *to_cxl_dax_region(struct device *dev);
u64 cxl_port_get_spa_cache_alias(struct cxl_port *endpoint, u64 spa);
int cxl_region_discovery(struct cxl_memdev *cxlmd);
#else
-static inline bool is_cxl_pmem_region(struct device *dev)
-{
- return false;
-}
-static inline struct cxl_pmem_region *to_cxl_pmem_region(struct device *dev)
-{
- return NULL;
-}
static inline int cxl_add_to_region(struct cxl_endpoint_decoder *cxled)
{
return 0;
@@ -933,6 +923,20 @@ static inline int cxl_region_discovery(struct cxl_memdev *cxlmd)
}
#endif
+#ifdef CONFIG_CXL_PMEM_REGION
+bool is_cxl_pmem_region(struct device *dev);
+struct cxl_pmem_region *to_cxl_pmem_region(struct device *dev);
+#else
+static inline bool is_cxl_pmem_region(struct device *dev)
+{
+ return false;
+}
+static inline struct cxl_pmem_region *to_cxl_pmem_region(struct device *dev)
+{
+ return NULL;
+}
+#endif
+
void cxl_endpoint_parse_cdat(struct cxl_port *port);
void cxl_switch_parse_cdat(struct cxl_dport *dport);
diff --git a/tools/testing/cxl/Kbuild b/tools/testing/cxl/Kbuild
index ad2496b38fdd..024922326a6b 100644
--- a/tools/testing/cxl/Kbuild
+++ b/tools/testing/cxl/Kbuild
@@ -59,7 +59,8 @@ cxl_core-y += $(CXL_CORE_SRC)/pmu.o
cxl_core-y += $(CXL_CORE_SRC)/cdat.o
cxl_core-y += $(CXL_CORE_SRC)/ras.o
cxl_core-$(CONFIG_TRACING) += $(CXL_CORE_SRC)/trace.o
-cxl_core-$(CONFIG_CXL_REGION) += $(CXL_CORE_SRC)/region.o $(CXL_CORE_SRC)/pmem_region.o
+cxl_core-$(CONFIG_CXL_REGION) += $(CXL_CORE_SRC)/region.o
+cxl_core-$(CONFIG_CXL_PMEM_REGION) += $(CXL_CORE_SRC)/pmem_region.o
cxl_core-$(CONFIG_CXL_MCE) += $(CXL_CORE_SRC)/mce.o
cxl_core-$(CONFIG_CXL_FEATURES) += $(CXL_CORE_SRC)/features.o
cxl_core-$(CONFIG_CXL_EDAC_MEM_FEATURES) += $(CXL_CORE_SRC)/edac.o
--
2.34.1
^ permalink raw reply related [flat|nested] 53+ messages in thread
* [PATCH V5 15/17] cxl/pmem_region: Add sysfs attribute cxl region label updation/deletion
2026-01-09 12:44 ` [PATCH V5 00/17] Add CXL LSA 2.1 format support in nvdimm and cxl pmem Neeraj Kumar
` (13 preceding siblings ...)
2026-01-09 12:44 ` [PATCH V5 14/17] cxl/pmem_region: Introduce CONFIG_CXL_PMEM_REGION for core/pmem_region.c Neeraj Kumar
@ 2026-01-09 12:44 ` Neeraj Kumar
2026-01-14 17:00 ` Dave Jiang
2026-01-15 18:21 ` Jonathan Cameron
2026-01-09 12:44 ` [PATCH V5 16/17] cxl/pmem_region: Create pmem region using information parsed from LSA Neeraj Kumar
` (2 subsequent siblings)
17 siblings, 2 replies; 53+ messages in thread
From: Neeraj Kumar @ 2026-01-09 12:44 UTC (permalink / raw)
To: linux-cxl, nvdimm, linux-kernel, gost.dev
Cc: a.manzanares, vishak.g, neeraj.kernel, Neeraj Kumar
Using these attributes region label is added/deleted into LSA. These
attributes are called from userspace (ndctl) after region creation.
Signed-off-by: Neeraj Kumar <s.neeraj@samsung.com>
---
Documentation/ABI/testing/sysfs-bus-cxl | 22 +++++++
drivers/cxl/core/pmem_region.c | 88 +++++++++++++++++++++++++
drivers/cxl/cxl.h | 7 ++
3 files changed, 117 insertions(+)
diff --git a/Documentation/ABI/testing/sysfs-bus-cxl b/Documentation/ABI/testing/sysfs-bus-cxl
index c80a1b5a03db..011a5e8d354f 100644
--- a/Documentation/ABI/testing/sysfs-bus-cxl
+++ b/Documentation/ABI/testing/sysfs-bus-cxl
@@ -624,3 +624,25 @@ Description:
The count is persistent across power loss and wraps back to 0
upon overflow. If this file is not present, the device does not
have the necessary support for dirty tracking.
+
+
+What: /sys/bus/cxl/devices/regionZ/pmem_regionZ/region_label_update
+Date: Jan, 2026
+KernelVersion: v6.19
+Contact: linux-cxl@vger.kernel.org
+Description:
+ (RW) Write a boolean 'true' string value to this attribute to
+ update cxl region information into LSA as region label. It is
+ used to update cxl region information saved during cxl region
+ creation into LSA. This attribute must be written last during
+ cxl region creation. Reading this attribute indicates whether
+ the region label is active or not.
+
+
+What: /sys/bus/cxl/devices/regionZ/pmem_regionZ/region_label_delete
+Date: Jan, 2026
+KernelVersion: v6.19
+Contact: linux-cxl@vger.kernel.org
+Description:
+ (WO) When a boolean 'true' is written to this attribute then
+ pmem_region driver deletes cxl region label from LSA.
diff --git a/drivers/cxl/core/pmem_region.c b/drivers/cxl/core/pmem_region.c
index dcaab59108fd..53d3d81e9676 100644
--- a/drivers/cxl/core/pmem_region.c
+++ b/drivers/cxl/core/pmem_region.c
@@ -29,8 +29,96 @@ static void cxl_pmem_region_release(struct device *dev)
kfree(cxlr_pmem);
}
+static ssize_t region_label_update_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t len)
+{
+ struct cxl_pmem_region *cxlr_pmem = to_cxl_pmem_region(dev);
+ struct cxl_region *cxlr = cxlr_pmem->cxlr;
+ ssize_t rc;
+ bool update;
+
+ rc = kstrtobool(buf, &update);
+ if (rc)
+ return rc;
+
+ ACQUIRE(rwsem_write_kill, rwsem)(&cxl_rwsem.region);
+ if ((rc = ACQUIRE_ERR(rwsem_write_kill, &rwsem)))
+ return rc;
+
+ /* Region not yet committed */
+ if (update && cxlr && cxlr->params.state != CXL_CONFIG_COMMIT) {
+ dev_dbg(dev, "region not committed, can't update into LSA\n");
+ return -ENXIO;
+ }
+
+ if (!cxlr || !cxlr->cxlr_pmem || !cxlr->cxlr_pmem->nd_region)
+ return 0;
+
+ rc = nd_region_label_update(cxlr->cxlr_pmem->nd_region);
+ if (rc)
+ return rc;
+
+ cxlr->params.state_region_label = CXL_REGION_LABEL_ACTIVE;
+
+ return len;
+}
+
+static ssize_t region_label_update_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct cxl_pmem_region *cxlr_pmem = to_cxl_pmem_region(dev);
+ struct cxl_region *cxlr = cxlr_pmem->cxlr;
+ struct cxl_region_params *p = &cxlr->params;
+ ssize_t rc;
+
+ ACQUIRE(rwsem_read_intr, rwsem)(&cxl_rwsem.region);
+ if ((rc = ACQUIRE_ERR(rwsem_read_intr, &rwsem)))
+ return rc;
+
+ return sysfs_emit(buf, "%d\n", p->state_region_label);
+}
+static DEVICE_ATTR_RW(region_label_update);
+
+static ssize_t region_label_delete_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t len)
+{
+ struct cxl_pmem_region *cxlr_pmem = to_cxl_pmem_region(dev);
+ struct cxl_region *cxlr = cxlr_pmem->cxlr;
+ ssize_t rc;
+
+ ACQUIRE(rwsem_write_kill, rwsem)(&cxl_rwsem.region);
+ if ((rc = ACQUIRE_ERR(rwsem_write_kill, &rwsem)))
+ return rc;
+
+ if (!cxlr && !cxlr->cxlr_pmem && !cxlr->cxlr_pmem->nd_region)
+ return 0;
+
+ rc = nd_region_label_delete(cxlr->cxlr_pmem->nd_region);
+ if (rc)
+ return rc;
+
+ cxlr->params.state_region_label = CXL_REGION_LABEL_INACTIVE;
+
+ return len;
+}
+static DEVICE_ATTR_WO(region_label_delete);
+
+static struct attribute *cxl_pmem_region_attrs[] = {
+ &dev_attr_region_label_update.attr,
+ &dev_attr_region_label_delete.attr,
+ NULL
+};
+
+static struct attribute_group cxl_pmem_region_group = {
+ .attrs = cxl_pmem_region_attrs,
+};
+
static const struct attribute_group *cxl_pmem_region_attribute_groups[] = {
&cxl_base_attribute_group,
+ &cxl_pmem_region_group,
NULL
};
diff --git a/drivers/cxl/cxl.h b/drivers/cxl/cxl.h
index 6ac3b40cb5ff..8c76c4a981bf 100644
--- a/drivers/cxl/cxl.h
+++ b/drivers/cxl/cxl.h
@@ -473,9 +473,15 @@ enum cxl_config_state {
CXL_CONFIG_COMMIT,
};
+enum region_label_state {
+ CXL_REGION_LABEL_INACTIVE,
+ CXL_REGION_LABEL_ACTIVE,
+};
+
/**
* struct cxl_region_params - region settings
* @state: allow the driver to lockdown further parameter changes
+ * @state: region label state
* @uuid: unique id for persistent regions
* @interleave_ways: number of endpoints in the region
* @interleave_granularity: capacity each endpoint contributes to a stripe
@@ -488,6 +494,7 @@ enum cxl_config_state {
*/
struct cxl_region_params {
enum cxl_config_state state;
+ enum region_label_state state_region_label;
uuid_t uuid;
int interleave_ways;
int interleave_granularity;
--
2.34.1
^ permalink raw reply related [flat|nested] 53+ messages in thread
* [PATCH V5 16/17] cxl/pmem_region: Create pmem region using information parsed from LSA
2026-01-09 12:44 ` [PATCH V5 00/17] Add CXL LSA 2.1 format support in nvdimm and cxl pmem Neeraj Kumar
` (14 preceding siblings ...)
2026-01-09 12:44 ` [PATCH V5 15/17] cxl/pmem_region: Add sysfs attribute cxl region label updation/deletion Neeraj Kumar
@ 2026-01-09 12:44 ` Neeraj Kumar
2026-01-15 18:28 ` Jonathan Cameron
2026-01-09 12:44 ` [PATCH V5 17/17] cxl/pmem: Add CXL LSA 2.1 support in cxl pmem Neeraj Kumar
2026-01-21 15:37 ` [PATCH V5 00/17] Add CXL LSA 2.1 format support in nvdimm and " Dave Jiang
17 siblings, 1 reply; 53+ messages in thread
From: Neeraj Kumar @ 2026-01-09 12:44 UTC (permalink / raw)
To: linux-cxl, nvdimm, linux-kernel, gost.dev
Cc: a.manzanares, vishak.g, neeraj.kernel, Neeraj Kumar
create_pmem_region() creates CXL region based on region information
parsed from the Label Storage Area (LSA). This routine requires cxl
endpoint decoder and root decoder. Add cxl_find_root_decoder_by_port()
and cxl_find_free_ep_decoder() to find the root decoder and a free
endpoint decoder respectively.
Signed-off-by: Neeraj Kumar <s.neeraj@samsung.com>
---
drivers/cxl/core/core.h | 5 ++
drivers/cxl/core/pmem_region.c | 136 +++++++++++++++++++++++++++++++++
drivers/cxl/core/region.c | 21 +++--
drivers/cxl/cxl.h | 5 ++
4 files changed, 159 insertions(+), 8 deletions(-)
diff --git a/drivers/cxl/core/core.h b/drivers/cxl/core/core.h
index 5ae693269771..8421ea0ef834 100644
--- a/drivers/cxl/core/core.h
+++ b/drivers/cxl/core/core.h
@@ -46,6 +46,7 @@ struct cxl_region *cxl_create_region(struct cxl_root_decoder *cxlrd,
struct cxl_pmem_region_params *pmem_params,
struct cxl_endpoint_decoder *cxled);
struct cxl_region *to_cxl_region(struct device *dev);
+bool is_free_decoder(struct device *dev);
#else
static inline u64 cxl_dpa_to_hpa(struct cxl_region *cxlr,
@@ -87,6 +88,10 @@ static inline struct cxl_region *to_cxl_region(struct device *dev)
{
return NULL;
}
+static inline bool is_free_decoder(struct device *dev)
+{
+ return false;
+}
#define CXL_REGION_ATTR(x) NULL
#define CXL_REGION_TYPE(x) NULL
#define SET_CXL_REGION_ATTR(x)
diff --git a/drivers/cxl/core/pmem_region.c b/drivers/cxl/core/pmem_region.c
index 53d3d81e9676..4a8cf8322cf0 100644
--- a/drivers/cxl/core/pmem_region.c
+++ b/drivers/cxl/core/pmem_region.c
@@ -287,3 +287,139 @@ int devm_cxl_add_pmem_region(struct cxl_region *cxlr)
cxlr->cxl_nvb = NULL;
return rc;
}
+
+static int match_root_decoder_by_dport(struct device *dev, const void *data)
+{
+ const struct cxl_port *ep_port = data;
+ struct cxl_root_decoder *cxlrd;
+ struct cxl_port *root_port;
+ struct cxl_decoder *cxld;
+ struct cxl_dport *dport;
+ bool dport_matched = false;
+
+ if (!is_root_decoder(dev))
+ return 0;
+
+ cxld = to_cxl_decoder(dev);
+ if (!(cxld->flags & CXL_DECODER_F_PMEM))
+ return 0;
+
+ cxlrd = to_cxl_root_decoder(dev);
+
+ root_port = cxlrd_to_port(cxlrd);
+ dport = cxl_find_dport_by_dev(root_port, ep_port->host_bridge);
+ if (!dport)
+ return 0;
+
+ for (int i = 0; i < cxlrd->cxlsd.nr_targets; i++) {
+ if (dport == cxlrd->cxlsd.target[i]) {
+ dport_matched = true;
+ break;
+ }
+ }
+
+ if (!dport_matched)
+ return 0;
+
+ return is_root_decoder(dev);
+}
+
+/**
+ * cxl_find_root_decoder_by_port() - find a cxl root decoder on cxl bus
+ * @port: any descendant port in CXL port topology
+ * @cxled: endpoint decoder
+ *
+ * Caller of this function must call put_device() when done as a device ref
+ * is taken via device_find_child()
+ */
+static struct cxl_root_decoder *
+cxl_find_root_decoder_by_port(struct cxl_port *port,
+ struct cxl_endpoint_decoder *cxled)
+{
+ struct cxl_root *cxl_root __free(put_cxl_root) = find_cxl_root(port);
+ struct cxl_port *ep_port = cxled_to_port(cxled);
+ struct device *dev;
+
+ if (!cxl_root)
+ return NULL;
+
+ dev = device_find_child(&cxl_root->port.dev, ep_port,
+ match_root_decoder_by_dport);
+ if (!dev)
+ return NULL;
+
+ return to_cxl_root_decoder(dev);
+}
+
+static int match_free_ep_decoder(struct device *dev, const void *data)
+{
+ if (!is_endpoint_decoder(dev))
+ return 0;
+
+ return is_free_decoder(dev);
+}
+
+/**
+ * cxl_find_endpoint_decoder_by_port() - find a cxl root decoder on cxl bus
+ * @port: any descendant port in CXL port topology
+ *
+ * Caller of this function must call put_device() when done as a device ref
+ * is taken via device_find_child()
+ */
+static struct cxl_decoder *cxl_find_free_ep_decoder(struct cxl_port *port)
+{
+ struct device *dev;
+
+ dev = device_find_child(&port->dev, NULL, match_free_ep_decoder);
+ if (!dev)
+ return NULL;
+
+ return to_cxl_decoder(dev);
+}
+
+void create_pmem_region(struct nvdimm *nvdimm)
+{
+ struct cxl_region *cxlr;
+ struct cxl_memdev *cxlmd;
+ struct cxl_nvdimm *cxl_nvd;
+ struct cxl_endpoint_decoder *cxled;
+ struct cxl_pmem_region_params *params;
+
+ if (!nvdimm_has_cxl_region(nvdimm))
+ return;
+
+ lockdep_assert_held(&cxl_rwsem.region);
+ cxl_nvd = nvdimm_provider_data(nvdimm);
+ params = nvdimm_get_cxl_region_param(nvdimm);
+ cxlmd = cxl_nvd->cxlmd;
+
+ /* TODO: Region creation support only for interleave way == 1 */
+ if (!(params->nlabel == 1)) {
+ dev_dbg(&cxlmd->dev,
+ "Region Creation is not supported with iw > 1\n");
+ return;
+ }
+
+ struct cxl_decoder *cxld __free(put_cxl_decoder) =
+ cxl_find_free_ep_decoder(cxlmd->endpoint);
+ if (!cxld) {
+ dev_err(&cxlmd->dev, "CXL endpoint decoder not found\n");
+ return;
+ }
+
+ cxled = to_cxl_endpoint_decoder(&cxld->dev);
+
+ struct cxl_root_decoder *cxlrd __free(put_cxl_root_decoder) =
+ cxl_find_root_decoder_by_port(cxlmd->endpoint, cxled);
+ if (!cxlrd) {
+ dev_err(&cxlmd->dev, "CXL root decoder not found\n");
+ return;
+ }
+
+ cxlr = cxl_create_region(cxlrd, CXL_PARTMODE_PMEM,
+ atomic_read(&cxlrd->region_id),
+ params, cxled);
+ if (IS_ERR(cxlr))
+ dev_warn(&cxlmd->dev, "Region Creation failed\n");
+}
+EXPORT_SYMBOL_NS_GPL(create_pmem_region, "CXL");
diff --git a/drivers/cxl/core/region.c b/drivers/cxl/core/region.c
index 9a86d1c467b2..1b39f7028ca1 100644
--- a/drivers/cxl/core/region.c
+++ b/drivers/cxl/core/region.c
@@ -838,25 +838,22 @@ static int check_commit_order(struct device *dev, void *data)
return 0;
}
-static int match_free_decoder(struct device *dev, const void *data)
+bool is_free_decoder(struct device *dev)
{
struct cxl_port *port = to_cxl_port(dev->parent);
struct cxl_decoder *cxld;
int rc;
- if (!is_switch_decoder(dev))
- return 0;
-
cxld = to_cxl_decoder(dev);
if (cxld->id != port->commit_end + 1)
- return 0;
+ return false;
if (cxld->region) {
dev_dbg(dev->parent,
"next decoder to commit (%s) is already reserved (%s)\n",
dev_name(dev), dev_name(&cxld->region->dev));
- return 0;
+ return false;
}
rc = device_for_each_child_reverse_from(dev->parent, dev, NULL,
@@ -865,9 +862,17 @@ static int match_free_decoder(struct device *dev, const void *data)
dev_dbg(dev->parent,
"unable to allocate %s due to out of order shutdown\n",
dev_name(dev));
- return 0;
+ return false;
}
- return 1;
+ return true;
+}
+
+static int match_free_decoder(struct device *dev, const void *data)
+{
+ if (!is_switch_decoder(dev))
+ return 0;
+
+ return is_free_decoder(dev);
}
static bool spa_maps_hpa(const struct cxl_region_params *p,
diff --git a/drivers/cxl/cxl.h b/drivers/cxl/cxl.h
index 8c76c4a981bf..088841a3e238 100644
--- a/drivers/cxl/cxl.h
+++ b/drivers/cxl/cxl.h
@@ -792,6 +792,7 @@ struct cxl_root *find_cxl_root(struct cxl_port *port);
DEFINE_FREE(put_cxl_root, struct cxl_root *, if (_T) put_device(&_T->port.dev))
DEFINE_FREE(put_cxl_port, struct cxl_port *, if (!IS_ERR_OR_NULL(_T)) put_device(&_T->dev))
DEFINE_FREE(put_cxl_root_decoder, struct cxl_root_decoder *, if (!IS_ERR_OR_NULL(_T)) put_device(&_T->cxlsd.cxld.dev))
+DEFINE_FREE(put_cxl_decoder, struct cxl_decoder *, if (!IS_ERR_OR_NULL(_T)) put_device(&_T->dev))
DEFINE_FREE(put_cxl_region, struct cxl_region *, if (!IS_ERR_OR_NULL(_T)) put_device(&_T->dev))
int devm_cxl_enumerate_ports(struct cxl_memdev *cxlmd);
@@ -933,6 +934,7 @@ static inline int cxl_region_discovery(struct cxl_memdev *cxlmd)
#ifdef CONFIG_CXL_PMEM_REGION
bool is_cxl_pmem_region(struct device *dev);
struct cxl_pmem_region *to_cxl_pmem_region(struct device *dev);
+void create_pmem_region(struct nvdimm *nvdimm);
#else
static inline bool is_cxl_pmem_region(struct device *dev)
{
@@ -942,6 +944,9 @@ static inline struct cxl_pmem_region *to_cxl_pmem_region(struct device *dev)
{
return NULL;
}
+static inline void create_pmem_region(struct nvdimm *nvdimm)
+{
+}
#endif
void cxl_endpoint_parse_cdat(struct cxl_port *port);
--
2.34.1
^ permalink raw reply related [flat|nested] 53+ messages in thread
* [PATCH V5 17/17] cxl/pmem: Add CXL LSA 2.1 support in cxl pmem
2026-01-09 12:44 ` [PATCH V5 00/17] Add CXL LSA 2.1 format support in nvdimm and cxl pmem Neeraj Kumar
` (15 preceding siblings ...)
2026-01-09 12:44 ` [PATCH V5 16/17] cxl/pmem_region: Create pmem region using information parsed from LSA Neeraj Kumar
@ 2026-01-09 12:44 ` Neeraj Kumar
2026-01-15 18:29 ` Jonathan Cameron
2026-01-21 15:37 ` [PATCH V5 00/17] Add CXL LSA 2.1 format support in nvdimm and " Dave Jiang
17 siblings, 1 reply; 53+ messages in thread
From: Neeraj Kumar @ 2026-01-09 12:44 UTC (permalink / raw)
To: linux-cxl, nvdimm, linux-kernel, gost.dev
Cc: a.manzanares, vishak.g, neeraj.kernel, Neeraj Kumar
Add support of CXL LSA 2.1 using NDD_REGION_LABELING flag. It creates
cxl region based on region information parsed from LSA
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Neeraj Kumar <s.neeraj@samsung.com>
---
drivers/cxl/pmem.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/drivers/cxl/pmem.c b/drivers/cxl/pmem.c
index a6eba3572090..5970d1792be8 100644
--- a/drivers/cxl/pmem.c
+++ b/drivers/cxl/pmem.c
@@ -135,6 +135,7 @@ static int cxl_nvdimm_probe(struct device *dev)
return rc;
set_bit(NDD_LABELING, &flags);
+ set_bit(NDD_REGION_LABELING, &flags);
set_bit(NDD_REGISTER_SYNC, &flags);
set_bit(ND_CMD_GET_CONFIG_SIZE, &cmd_mask);
set_bit(ND_CMD_GET_CONFIG_DATA, &cmd_mask);
@@ -155,6 +156,7 @@ static int cxl_nvdimm_probe(struct device *dev)
return -ENOMEM;
dev_set_drvdata(dev, nvdimm);
+ create_pmem_region(nvdimm);
return devm_add_action_or_reset(dev, unregister_nvdimm, nvdimm);
}
--
2.34.1
^ permalink raw reply related [flat|nested] 53+ messages in thread
* Re: [PATCH V5 15/17] cxl/pmem_region: Add sysfs attribute cxl region label updation/deletion
2026-01-09 12:44 ` [PATCH V5 15/17] cxl/pmem_region: Add sysfs attribute cxl region label updation/deletion Neeraj Kumar
@ 2026-01-14 17:00 ` Dave Jiang
2026-01-23 11:22 ` Neeraj Kumar
2026-01-15 18:21 ` Jonathan Cameron
1 sibling, 1 reply; 53+ messages in thread
From: Dave Jiang @ 2026-01-14 17:00 UTC (permalink / raw)
To: Neeraj Kumar, linux-cxl, nvdimm, linux-kernel, gost.dev
Cc: a.manzanares, vishak.g, neeraj.kernel
On 1/9/26 5:44 AM, Neeraj Kumar wrote:
> Using these attributes region label is added/deleted into LSA. These
> attributes are called from userspace (ndctl) after region creation.
>
> Signed-off-by: Neeraj Kumar <s.neeraj@samsung.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
You'll need to update the KernelVersion to v7.0.
> ---
> Documentation/ABI/testing/sysfs-bus-cxl | 22 +++++++
> drivers/cxl/core/pmem_region.c | 88 +++++++++++++++++++++++++
> drivers/cxl/cxl.h | 7 ++
> 3 files changed, 117 insertions(+)
>
> diff --git a/Documentation/ABI/testing/sysfs-bus-cxl b/Documentation/ABI/testing/sysfs-bus-cxl
> index c80a1b5a03db..011a5e8d354f 100644
> --- a/Documentation/ABI/testing/sysfs-bus-cxl
> +++ b/Documentation/ABI/testing/sysfs-bus-cxl
> @@ -624,3 +624,25 @@ Description:
> The count is persistent across power loss and wraps back to 0
> upon overflow. If this file is not present, the device does not
> have the necessary support for dirty tracking.
> +
> +
> +What: /sys/bus/cxl/devices/regionZ/pmem_regionZ/region_label_update
> +Date: Jan, 2026
> +KernelVersion: v6.19
> +Contact: linux-cxl@vger.kernel.org
> +Description:
> + (RW) Write a boolean 'true' string value to this attribute to
> + update cxl region information into LSA as region label. It is
> + used to update cxl region information saved during cxl region
> + creation into LSA. This attribute must be written last during
> + cxl region creation. Reading this attribute indicates whether
> + the region label is active or not.
> +
> +
> +What: /sys/bus/cxl/devices/regionZ/pmem_regionZ/region_label_delete
> +Date: Jan, 2026
> +KernelVersion: v6.19
> +Contact: linux-cxl@vger.kernel.org
> +Description:
> + (WO) When a boolean 'true' is written to this attribute then
> + pmem_region driver deletes cxl region label from LSA.
> diff --git a/drivers/cxl/core/pmem_region.c b/drivers/cxl/core/pmem_region.c
> index dcaab59108fd..53d3d81e9676 100644
> --- a/drivers/cxl/core/pmem_region.c
> +++ b/drivers/cxl/core/pmem_region.c
> @@ -29,8 +29,96 @@ static void cxl_pmem_region_release(struct device *dev)
> kfree(cxlr_pmem);
> }
>
> +static ssize_t region_label_update_store(struct device *dev,
> + struct device_attribute *attr,
> + const char *buf, size_t len)
> +{
> + struct cxl_pmem_region *cxlr_pmem = to_cxl_pmem_region(dev);
> + struct cxl_region *cxlr = cxlr_pmem->cxlr;
> + ssize_t rc;
> + bool update;
> +
> + rc = kstrtobool(buf, &update);
> + if (rc)
> + return rc;
> +
> + ACQUIRE(rwsem_write_kill, rwsem)(&cxl_rwsem.region);
> + if ((rc = ACQUIRE_ERR(rwsem_write_kill, &rwsem)))
> + return rc;
> +
> + /* Region not yet committed */
> + if (update && cxlr && cxlr->params.state != CXL_CONFIG_COMMIT) {
> + dev_dbg(dev, "region not committed, can't update into LSA\n");
> + return -ENXIO;
> + }
> +
> + if (!cxlr || !cxlr->cxlr_pmem || !cxlr->cxlr_pmem->nd_region)
> + return 0;
> +
> + rc = nd_region_label_update(cxlr->cxlr_pmem->nd_region);
> + if (rc)
> + return rc;
> +
> + cxlr->params.state_region_label = CXL_REGION_LABEL_ACTIVE;
> +
> + return len;
> +}
> +
> +static ssize_t region_label_update_show(struct device *dev,
> + struct device_attribute *attr,
> + char *buf)
> +{
> + struct cxl_pmem_region *cxlr_pmem = to_cxl_pmem_region(dev);
> + struct cxl_region *cxlr = cxlr_pmem->cxlr;
> + struct cxl_region_params *p = &cxlr->params;
> + ssize_t rc;
> +
> + ACQUIRE(rwsem_read_intr, rwsem)(&cxl_rwsem.region);
> + if ((rc = ACQUIRE_ERR(rwsem_read_intr, &rwsem)))
> + return rc;
> +
> + return sysfs_emit(buf, "%d\n", p->state_region_label);
> +}
> +static DEVICE_ATTR_RW(region_label_update);
> +
> +static ssize_t region_label_delete_store(struct device *dev,
> + struct device_attribute *attr,
> + const char *buf, size_t len)
> +{
> + struct cxl_pmem_region *cxlr_pmem = to_cxl_pmem_region(dev);
> + struct cxl_region *cxlr = cxlr_pmem->cxlr;
> + ssize_t rc;
> +
> + ACQUIRE(rwsem_write_kill, rwsem)(&cxl_rwsem.region);
> + if ((rc = ACQUIRE_ERR(rwsem_write_kill, &rwsem)))
> + return rc;
> +
> + if (!cxlr && !cxlr->cxlr_pmem && !cxlr->cxlr_pmem->nd_region)
> + return 0;
> +
> + rc = nd_region_label_delete(cxlr->cxlr_pmem->nd_region);
> + if (rc)
> + return rc;
> +
> + cxlr->params.state_region_label = CXL_REGION_LABEL_INACTIVE;
> +
> + return len;
> +}
> +static DEVICE_ATTR_WO(region_label_delete);
> +
> +static struct attribute *cxl_pmem_region_attrs[] = {
> + &dev_attr_region_label_update.attr,
> + &dev_attr_region_label_delete.attr,
> + NULL
> +};
> +
> +static struct attribute_group cxl_pmem_region_group = {
> + .attrs = cxl_pmem_region_attrs,
> +};
> +
> static const struct attribute_group *cxl_pmem_region_attribute_groups[] = {
> &cxl_base_attribute_group,
> + &cxl_pmem_region_group,
> NULL
> };
>
> diff --git a/drivers/cxl/cxl.h b/drivers/cxl/cxl.h
> index 6ac3b40cb5ff..8c76c4a981bf 100644
> --- a/drivers/cxl/cxl.h
> +++ b/drivers/cxl/cxl.h
> @@ -473,9 +473,15 @@ enum cxl_config_state {
> CXL_CONFIG_COMMIT,
> };
>
> +enum region_label_state {
> + CXL_REGION_LABEL_INACTIVE,
> + CXL_REGION_LABEL_ACTIVE,
> +};
> +
> /**
> * struct cxl_region_params - region settings
> * @state: allow the driver to lockdown further parameter changes
> + * @state: region label state
> * @uuid: unique id for persistent regions
> * @interleave_ways: number of endpoints in the region
> * @interleave_granularity: capacity each endpoint contributes to a stripe
> @@ -488,6 +494,7 @@ enum cxl_config_state {
> */
> struct cxl_region_params {
> enum cxl_config_state state;
> + enum region_label_state state_region_label;
> uuid_t uuid;
> int interleave_ways;
> int interleave_granularity;
^ permalink raw reply [flat|nested] 53+ messages in thread
* Re: [PATCH V5 04/17] nvdimm/label: Include region label in slot validation
2026-01-09 12:44 ` [PATCH V5 04/17] nvdimm/label: Include region label in slot validation Neeraj Kumar
@ 2026-01-14 21:20 ` Ira Weiny
2026-01-23 11:02 ` Neeraj Kumar
2026-01-15 17:55 ` Jonathan Cameron
2026-01-21 0:38 ` Ira Weiny
2 siblings, 1 reply; 53+ messages in thread
From: Ira Weiny @ 2026-01-14 21:20 UTC (permalink / raw)
To: Neeraj Kumar, linux-cxl, nvdimm, linux-kernel, gost.dev
Cc: a.manzanares, vishak.g, neeraj.kernel, Neeraj Kumar
Neeraj Kumar wrote:
> Prior to LSA 2.1 Support, label in slot means only namespace
> label. But with LSA 2.1 a label can be either namespace or
> region label.
>
> Slot validation routine validates label slot by calculating
> label checksum. It was only validating namespace label.
> This changeset also validates region label if present.
>
> In previous patch to_lsa_label() was introduced along with
> to_label(). to_label() returns only namespace label whereas
> to_lsa_label() returns union nd_lsa_label*
>
> In this patch We have converted all usage of to_label()
NIT: don't use 'We'
> to to_lsa_label()
>
> Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>
> Reviewed-by: Dave Jiang <dave.jiang@intel.com>
> Signed-off-by: Neeraj Kumar <s.neeraj@samsung.com>
> ---
> drivers/nvdimm/label.c | 94 ++++++++++++++++++++++++++++--------------
> 1 file changed, 64 insertions(+), 30 deletions(-)
>
> diff --git a/drivers/nvdimm/label.c b/drivers/nvdimm/label.c
> index 17e2a1f5a6da..9854cb45fb62 100644
> --- a/drivers/nvdimm/label.c
> +++ b/drivers/nvdimm/label.c
> @@ -312,16 +312,6 @@ static union nd_lsa_label *to_lsa_label(struct nvdimm_drvdata *ndd, int slot)
> return (union nd_lsa_label *) label;
> }
>
> -static struct nd_namespace_label *to_label(struct nvdimm_drvdata *ndd, int slot)
> -{
> - unsigned long label, base;
> -
> - base = (unsigned long) nd_label_base(ndd);
> - label = base + sizeof_namespace_label(ndd) * slot;
> -
> - return (struct nd_namespace_label *) label;
> -}
> -
> #define for_each_clear_bit_le(bit, addr, size) \
> for ((bit) = find_next_zero_bit_le((addr), (size), 0); \
> (bit) < (size); \
> @@ -382,7 +372,7 @@ static bool nsl_validate_checksum(struct nvdimm_drvdata *ndd,
> {
> u64 sum, sum_save;
>
> - if (!ndd->cxl && !efi_namespace_label_has(ndd, checksum))
> + if (!efi_namespace_label_has(ndd, checksum))
What does this change have to do with region label validation during slot
validation?
> return true;
>
> sum_save = nsl_get_checksum(ndd, nd_label);
> @@ -397,13 +387,25 @@ static void nsl_calculate_checksum(struct nvdimm_drvdata *ndd,
> {
> u64 sum;
>
> - if (!ndd->cxl && !efi_namespace_label_has(ndd, checksum))
> + if (!efi_namespace_label_has(ndd, checksum))
This and the above seem like cleanups because efi_namespace_label_has()
already checks !ndd->cxl? Was that the intent? Perhaps as a separate
cleanup?
Rest of the patch looks reasonable,
Ira
> return;
> nsl_set_checksum(ndd, nd_label, 0);
> sum = nd_fletcher64(nd_label, sizeof_namespace_label(ndd), 1);
> nsl_set_checksum(ndd, nd_label, sum);
> }
>
> +static bool region_label_validate_checksum(struct nvdimm_drvdata *ndd,
> + struct cxl_region_label *region_label)
> +{
> + u64 sum, sum_save;
> +
> + sum_save = __le64_to_cpu(region_label->checksum);
> + region_label->checksum = __cpu_to_le64(0);
> + sum = nd_fletcher64(region_label, sizeof_namespace_label(ndd), 1);
> + region_label->checksum = __cpu_to_le64(sum_save);
> + return sum == sum_save;
> +}
> +
> static void region_label_calculate_checksum(struct nvdimm_drvdata *ndd,
> struct cxl_region_label *region_label)
> {
> @@ -415,16 +417,34 @@ static void region_label_calculate_checksum(struct nvdimm_drvdata *ndd,
> }
>
> static bool slot_valid(struct nvdimm_drvdata *ndd,
> - struct nd_namespace_label *nd_label, u32 slot)
> + union nd_lsa_label *lsa_label, u32 slot)
> {
> + struct cxl_region_label *region_label = &lsa_label->region_label;
> + struct nd_namespace_label *nd_label = &lsa_label->ns_label;
> + enum label_type type;
> bool valid;
> + static const char * const label_name[] = {
> + [RG_LABEL_TYPE] = "region",
> + [NS_LABEL_TYPE] = "namespace",
> + };
>
> /* check that we are written where we expect to be written */
> - if (slot != nsl_get_slot(ndd, nd_label))
> - return false;
> - valid = nsl_validate_checksum(ndd, nd_label);
> + if (is_region_label(ndd, lsa_label)) {
> + type = RG_LABEL_TYPE;
> + if (slot != __le32_to_cpu(region_label->slot))
> + return false;
> + valid = region_label_validate_checksum(ndd, region_label);
> + } else {
> + type = NS_LABEL_TYPE;
> + if (slot != nsl_get_slot(ndd, nd_label))
> + return false;
> + valid = nsl_validate_checksum(ndd, nd_label);
> + }
> +
> if (!valid)
> - dev_dbg(ndd->dev, "fail checksum. slot: %d\n", slot);
> + dev_dbg(ndd->dev, "%s label checksum fail. slot: %d\n",
> + label_name[type], slot);
> +
> return valid;
> }
>
> @@ -440,14 +460,16 @@ int nd_label_reserve_dpa(struct nvdimm_drvdata *ndd)
> for_each_clear_bit_le(slot, free, nslot) {
> struct nd_namespace_label *nd_label;
> struct nd_region *nd_region = NULL;
> + union nd_lsa_label *lsa_label;
> struct nd_label_id label_id;
> struct resource *res;
> uuid_t label_uuid;
> u32 flags;
>
> - nd_label = to_label(ndd, slot);
> + lsa_label = to_lsa_label(ndd, slot);
> + nd_label = &lsa_label->ns_label;
>
> - if (!slot_valid(ndd, nd_label, slot))
> + if (!slot_valid(ndd, lsa_label, slot))
> continue;
>
> nsl_get_uuid(ndd, nd_label, &label_uuid);
> @@ -598,18 +620,30 @@ int nd_label_active_count(struct nvdimm_drvdata *ndd)
> return 0;
>
> for_each_clear_bit_le(slot, free, nslot) {
> + struct cxl_region_label *region_label;
> struct nd_namespace_label *nd_label;
> -
> - nd_label = to_label(ndd, slot);
> -
> - if (!slot_valid(ndd, nd_label, slot)) {
> - u32 label_slot = nsl_get_slot(ndd, nd_label);
> - u64 size = nsl_get_rawsize(ndd, nd_label);
> - u64 dpa = nsl_get_dpa(ndd, nd_label);
> + union nd_lsa_label *lsa_label;
> + u32 lslot;
> + u64 size, dpa;
> +
> + lsa_label = to_lsa_label(ndd, slot);
> + nd_label = &lsa_label->ns_label;
> + region_label = &lsa_label->region_label;
> +
> + if (!slot_valid(ndd, lsa_label, slot)) {
> + if (is_region_label(ndd, lsa_label)) {
> + lslot = __le32_to_cpu(region_label->slot);
> + size = __le64_to_cpu(region_label->rawsize);
> + dpa = __le64_to_cpu(region_label->dpa);
> + } else {
> + lslot = nsl_get_slot(ndd, nd_label);
> + size = nsl_get_rawsize(ndd, nd_label);
> + dpa = nsl_get_dpa(ndd, nd_label);
> + }
>
> dev_dbg(ndd->dev,
> "slot%d invalid slot: %d dpa: %llx size: %llx\n",
> - slot, label_slot, dpa, size);
> + slot, lslot, dpa, size);
> continue;
> }
> count++;
> @@ -627,10 +661,10 @@ union nd_lsa_label *nd_label_active(struct nvdimm_drvdata *ndd, int n)
> return NULL;
>
> for_each_clear_bit_le(slot, free, nslot) {
> - struct nd_namespace_label *nd_label;
> + union nd_lsa_label *lsa_label;
>
> - nd_label = to_label(ndd, slot);
> - if (!slot_valid(ndd, nd_label, slot))
> + lsa_label = to_lsa_label(ndd, slot);
> + if (!slot_valid(ndd, lsa_label, slot))
> continue;
>
> if (n-- == 0)
> --
> 2.34.1
>
>
^ permalink raw reply [flat|nested] 53+ messages in thread
* Re: [PATCH V5 01/17] nvdimm/label: Introduce NDD_REGION_LABELING flag to set region label
2026-01-09 12:44 ` [PATCH V5 01/17] nvdimm/label: Introduce NDD_REGION_LABELING flag to set region label Neeraj Kumar
@ 2026-01-14 21:22 ` Ira Weiny
0 siblings, 0 replies; 53+ messages in thread
From: Ira Weiny @ 2026-01-14 21:22 UTC (permalink / raw)
To: Neeraj Kumar, linux-cxl, nvdimm, linux-kernel, gost.dev
Cc: a.manzanares, vishak.g, neeraj.kernel, Neeraj Kumar
Neeraj Kumar wrote:
> Prior to LSA 2.1 version, LSA contain only namespace labels. LSA 2.1
> introduced in CXL 2.0 Spec, which contain region label along with
> namespace label.
>
> NDD_LABELING flag is used for namespace. Introduced NDD_REGION_LABELING
> flag for region label. Based on these flags nvdimm driver performs
> operation on namespace label or region label.
>
> NDD_REGION_LABELING will be utilized by cxl driver to enable LSA 2.1
> region label support
>
> Accordingly updated label index version
>
> Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>
> Reviewed-by: Dave Jiang <dave.jiang@intel.com>
> Signed-off-by: Neeraj Kumar <s.neeraj@samsung.com>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
[snip]
^ permalink raw reply [flat|nested] 53+ messages in thread
* Re: [PATCH V5 03/17] nvdimm/label: Add namespace/region label support as per LSA 2.1
2026-01-09 12:44 ` [PATCH V5 03/17] nvdimm/label: Add namespace/region label support as per LSA 2.1 Neeraj Kumar
@ 2026-01-15 17:45 ` Jonathan Cameron
2026-01-23 10:57 ` Neeraj Kumar
2026-01-21 0:35 ` Ira Weiny
1 sibling, 1 reply; 53+ messages in thread
From: Jonathan Cameron @ 2026-01-15 17:45 UTC (permalink / raw)
To: Neeraj Kumar
Cc: linux-cxl, nvdimm, linux-kernel, gost.dev, a.manzanares, vishak.g,
neeraj.kernel
On Fri, 9 Jan 2026 18:14:23 +0530
Neeraj Kumar <s.neeraj@samsung.com> wrote:
> Modify __pmem_label_update() to update region labels into LSA
>
> CXL 3.2 Spec mentions CXL LSA 2.1 Namespace Labels at section 9.13.2.5
> Modified __pmem_label_update() using setter functions to update
> namespace label as per CXL LSA 2.1
>
> Create export routine nd_region_label_update() used for creating
> region label into LSA. It will be used later from CXL subsystem
>
> Reviewed-by: Dave Jiang <dave.jiang@intel.com>
> Signed-off-by: Neeraj Kumar <s.neeraj@samsung.com>
Hi Neeraj,
There are a few more instances of copying in and out of UUIDs that
should be using the import and export functions.
With those fixed up,
Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>
> ---
> drivers/nvdimm/label.c | 360 ++++++++++++++++++++++++++------
> drivers/nvdimm/label.h | 17 +-
> drivers/nvdimm/namespace_devs.c | 20 +-
> drivers/nvdimm/nd.h | 51 +++++
> include/linux/libnvdimm.h | 8 +
> 5 files changed, 386 insertions(+), 70 deletions(-)
>
> diff --git a/drivers/nvdimm/label.c b/drivers/nvdimm/label.c
> index 0a9b6c5cb2c3..17e2a1f5a6da 100644
> --- a/drivers/nvdimm/label.c
> +++ b/drivers/nvdimm/label.c
> +static void region_label_update(struct nd_region *nd_region,
> + struct cxl_region_label *region_label,
> + struct nd_mapping *nd_mapping,
> + int pos, u64 flags, u32 slot)
> +{
> + struct nd_interleave_set *nd_set = nd_region->nd_set;
> + struct nvdimm_drvdata *ndd = to_ndd(nd_mapping);
> +
> + /* Set Region Label Format identification UUID */
> + uuid_copy((uuid_t *)region_label->type, &cxl_region_uuid);
Why is this one not an export_uuid()?
> +
> + /* Set Current Region Label UUID */
> + export_uuid(region_label->uuid, &nd_set->uuid);
> +
> + region_label->flags = __cpu_to_le32(flags);
> + region_label->nlabel = __cpu_to_le16(nd_region->ndr_mappings);
> + region_label->position = __cpu_to_le16(pos);
> + region_label->dpa = __cpu_to_le64(nd_mapping->start);
> + region_label->rawsize = __cpu_to_le64(nd_mapping->size);
> + region_label->hpa = __cpu_to_le64(nd_set->res->start);
> + region_label->slot = __cpu_to_le32(slot);
> + region_label->ig = __cpu_to_le32(nd_set->interleave_granularity);
> + region_label->align = __cpu_to_le32(0);
> +
> + /* Update fletcher64 Checksum */
> + region_label_calculate_checksum(ndd, region_label);
> +}
> diff --git a/drivers/nvdimm/nd.h b/drivers/nvdimm/nd.h
> index f631bd84d6f0..1b31eee3028e 100644
> --- a/drivers/nvdimm/nd.h
> +++ b/drivers/nvdimm/nd.h
...
> +}
> +
> +static inline bool is_region_label(struct nvdimm_drvdata *ndd,
> + union nd_lsa_label *lsa_label)
> +{
> + if (!ndd->cxl)
> + return false;
> +
> + return uuid_equal(&cxl_region_uuid,
> + (uuid_t *)lsa_label->region_label.type);
As below.
> +}
> +
> +static inline bool
> +region_label_uuid_equal(struct cxl_region_label *region_label,
> + const uuid_t *uuid)
> +{
> + return uuid_equal((uuid_t *)region_label->uuid, uuid);
Not appropriate to do an import_uuid() for this and similar cases?
In general I don't think we should see any casts to uuid_t *
There are 3 instances of this in the kernel and we should probably clean
all those up. There are a lot more doing the import!
Jonathan
> +}
^ permalink raw reply [flat|nested] 53+ messages in thread
* Re: [PATCH V5 04/17] nvdimm/label: Include region label in slot validation
2026-01-09 12:44 ` [PATCH V5 04/17] nvdimm/label: Include region label in slot validation Neeraj Kumar
2026-01-14 21:20 ` Ira Weiny
@ 2026-01-15 17:55 ` Jonathan Cameron
2026-01-21 0:38 ` Ira Weiny
2 siblings, 0 replies; 53+ messages in thread
From: Jonathan Cameron @ 2026-01-15 17:55 UTC (permalink / raw)
To: Neeraj Kumar
Cc: linux-cxl, nvdimm, linux-kernel, gost.dev, a.manzanares, vishak.g,
neeraj.kernel
On Fri, 9 Jan 2026 18:14:24 +0530
Neeraj Kumar <s.neeraj@samsung.com> wrote:
> Prior to LSA 2.1 Support, label in slot means only namespace
> label. But with LSA 2.1 a label can be either namespace or
> region label.
>
> Slot validation routine validates label slot by calculating
> label checksum. It was only validating namespace label.
> This changeset also validates region label if present.
>
> In previous patch to_lsa_label() was introduced along with
> to_label(). to_label() returns only namespace label whereas
> to_lsa_label() returns union nd_lsa_label*
>
> In this patch We have converted all usage of to_label()
> to to_lsa_label()
>
> Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>
> Reviewed-by: Dave Jiang <dave.jiang@intel.com>
> Signed-off-by: Neeraj Kumar <s.neeraj@samsung.com>
Hi
A few more things given you are going around again!
Jonathan
> ---
> drivers/nvdimm/label.c | 94 ++++++++++++++++++++++++++++--------------
> 1 file changed, 64 insertions(+), 30 deletions(-)
>
> diff --git a/drivers/nvdimm/label.c b/drivers/nvdimm/label.c
> index 17e2a1f5a6da..9854cb45fb62 100644
> --- a/drivers/nvdimm/label.c
> +++ b/drivers/nvdimm/label.c
> @@ -312,16 +312,6 @@ static union nd_lsa_label *to_lsa_label(struct nvdimm_drvdata *ndd, int slot)
> +
> static void region_label_calculate_checksum(struct nvdimm_drvdata *ndd,
> struct cxl_region_label *region_label)
> {
> @@ -415,16 +417,34 @@ static void region_label_calculate_checksum(struct nvdimm_drvdata *ndd,
> }
>
> static bool slot_valid(struct nvdimm_drvdata *ndd,
> - struct nd_namespace_label *nd_label, u32 slot)
> + union nd_lsa_label *lsa_label, u32 slot)
> {
> + struct cxl_region_label *region_label = &lsa_label->region_label;
> + struct nd_namespace_label *nd_label = &lsa_label->ns_label;
Move the assignments of these so we only do them if they are relevant.
That should make the code more resilient as any use outside those scopes
will fire compiler warnings.
> + enum label_type type;
> bool valid;
> + static const char * const label_name[] = {
> + [RG_LABEL_TYPE] = "region",
> + [NS_LABEL_TYPE] = "namespace",
> + };
>
> /* check that we are written where we expect to be written */
> - if (slot != nsl_get_slot(ndd, nd_label))
> - return false;
> - valid = nsl_validate_checksum(ndd, nd_label);
> + if (is_region_label(ndd, lsa_label)) {
> + type = RG_LABEL_TYPE;
> + if (slot != __le32_to_cpu(region_label->slot))
> + return false;
> + valid = region_label_validate_checksum(ndd, region_label);
> + } else {
> + type = NS_LABEL_TYPE;
> + if (slot != nsl_get_slot(ndd, nd_label))
> + return false;
> + valid = nsl_validate_checksum(ndd, nd_label);
> + }
> @@ -598,18 +620,30 @@ int nd_label_active_count(struct nvdimm_drvdata *ndd)
> return 0;
>
> for_each_clear_bit_le(slot, free, nslot) {
> + struct cxl_region_label *region_label;
> struct nd_namespace_label *nd_label;
> -
> - nd_label = to_label(ndd, slot);
> -
> - if (!slot_valid(ndd, nd_label, slot)) {
> - u32 label_slot = nsl_get_slot(ndd, nd_label);
> - u64 size = nsl_get_rawsize(ndd, nd_label);
> - u64 dpa = nsl_get_dpa(ndd, nd_label);
> + union nd_lsa_label *lsa_label;
> + u32 lslot;
Trivial but if you keep the label_slot naming, then the diff gets a little
smaller, and it's easier to see where the code moved. Don't worry about going just
over 80 chars. We are more relaxed these days as long as it helps readability.
> + u64 size, dpa;
> +
> + lsa_label = to_lsa_label(ndd, slot);
> + nd_label = &lsa_label->ns_label;
Move this
> + region_label = &lsa_label->region_label;
and this down to the scopes where they are meaningful.
So under if (is_region_label() and the else.
> +
> + if (!slot_valid(ndd, lsa_label, slot)) {
> + if (is_region_label(ndd, lsa_label)) {
> + lslot = __le32_to_cpu(region_label->slot);
> + size = __le64_to_cpu(region_label->rawsize);
> + dpa = __le64_to_cpu(region_label->dpa);
> + } else {
> + lslot = nsl_get_slot(ndd, nd_label);
> + size = nsl_get_rawsize(ndd, nd_label);
> + dpa = nsl_get_dpa(ndd, nd_label);
> + }
>
> dev_dbg(ndd->dev,
> "slot%d invalid slot: %d dpa: %llx size: %llx\n",
> - slot, label_slot, dpa, size);
> + slot, lslot, dpa, size);
> continue;
> }
> count++;
=
^ permalink raw reply [flat|nested] 53+ messages in thread
* Re: [PATCH V5 05/17] nvdimm/label: Skip region label during ns label DPA reservation
2026-01-09 12:44 ` [PATCH V5 05/17] nvdimm/label: Skip region label during ns label DPA reservation Neeraj Kumar
@ 2026-01-15 17:56 ` Jonathan Cameron
2026-01-21 0:41 ` Ira Weiny
1 sibling, 0 replies; 53+ messages in thread
From: Jonathan Cameron @ 2026-01-15 17:56 UTC (permalink / raw)
To: Neeraj Kumar
Cc: linux-cxl, nvdimm, linux-kernel, gost.dev, a.manzanares, vishak.g,
neeraj.kernel
On Fri, 9 Jan 2026 18:14:25 +0530
Neeraj Kumar <s.neeraj@samsung.com> wrote:
> CXL 3.2 Spec mentions CXL LSA 2.1 Namespace Labels at section
> 9.13.2.5. If Namespace label is present in LSA during
> nvdimm_probe() then dimm-physical-address(DPA) reservation is
> required. But this reservation is not required by cxl region
> label. Therefore if LSA scanning finds any region label, skip it.
>
> Reviewed-by: Dave Jiang <dave.jiang@intel.com>
> Signed-off-by: Neeraj Kumar <s.neeraj@samsung.com>
Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>
> ---
> drivers/nvdimm/label.c | 8 ++++++++
> 1 file changed, 8 insertions(+)
>
> diff --git a/drivers/nvdimm/label.c b/drivers/nvdimm/label.c
> index 9854cb45fb62..169692dfa12c 100644
> --- a/drivers/nvdimm/label.c
> +++ b/drivers/nvdimm/label.c
> @@ -469,6 +469,14 @@ int nd_label_reserve_dpa(struct nvdimm_drvdata *ndd)
> lsa_label = to_lsa_label(ndd, slot);
> nd_label = &lsa_label->ns_label;
>
> + /*
> + * Skip region label. If LSA label is region label
> + * then it don't require dimm-physical-address(DPA)
> + * reservation. Whereas its required for namespace label
> + */
> + if (is_region_label(ndd, lsa_label))
> + continue;
> +
> if (!slot_valid(ndd, lsa_label, slot))
> continue;
>
^ permalink raw reply [flat|nested] 53+ messages in thread
* Re: [PATCH V5 06/17] nvdimm/label: Preserve region label during namespace creation
2026-01-09 12:44 ` [PATCH V5 06/17] nvdimm/label: Preserve region label during namespace creation Neeraj Kumar
@ 2026-01-15 17:59 ` Jonathan Cameron
2026-01-21 0:43 ` Ira Weiny
1 sibling, 0 replies; 53+ messages in thread
From: Jonathan Cameron @ 2026-01-15 17:59 UTC (permalink / raw)
To: Neeraj Kumar
Cc: linux-cxl, nvdimm, linux-kernel, gost.dev, a.manzanares, vishak.g,
neeraj.kernel
On Fri, 9 Jan 2026 18:14:26 +0530
Neeraj Kumar <s.neeraj@samsung.com> wrote:
> During namespace creation we scan labels present in LSA using
> scan_labels(). Currently scan_labels() is only preserving
> namespace labels into label_ent list.
>
> In this patch we also preserve region label into label_ent list
>
> Reviewed-by: Dave Jiang <dave.jiang@intel.com>
> Signed-off-by: Neeraj Kumar <s.neeraj@samsung.com>
Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>
^ permalink raw reply [flat|nested] 53+ messages in thread
* Re: [PATCH V5 08/17] nvdimm/label: Preserve cxl region information from region label
2026-01-09 12:44 ` [PATCH V5 08/17] nvdimm/label: Preserve cxl region information from region label Neeraj Kumar
@ 2026-01-15 18:03 ` Jonathan Cameron
2026-01-23 11:08 ` Neeraj Kumar
2026-01-21 0:45 ` Ira Weiny
1 sibling, 1 reply; 53+ messages in thread
From: Jonathan Cameron @ 2026-01-15 18:03 UTC (permalink / raw)
To: Neeraj Kumar
Cc: linux-cxl, nvdimm, linux-kernel, gost.dev, a.manzanares, vishak.g,
neeraj.kernel
On Fri, 9 Jan 2026 18:14:28 +0530
Neeraj Kumar <s.neeraj@samsung.com> wrote:
> Preserve region information from region label during nvdimm_probe. This
> preserved region information is used for creating cxl region to achieve
> region persistency across reboot.
> This patch supports interleave way == 1, it is therefore it preserves
> only one region into LSA
>
> Reviewed-by: Dave Jiang <dave.jiang@intel.com>
> Signed-off-by: Neeraj Kumar <s.neeraj@samsung.com>
With change to import for getting the region uuid,
Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>
> diff --git a/drivers/nvdimm/label.c b/drivers/nvdimm/label.c
> index 2ad148bfe40b..7adb415f0926 100644
> --- a/drivers/nvdimm/label.c
> +++ b/drivers/nvdimm/label.c
> @@ -494,6 +494,42 @@ int nd_label_reserve_dpa(struct nvdimm_drvdata *ndd)
> return 0;
> }
>
> +int nvdimm_cxl_region_preserve(struct nvdimm_drvdata *ndd)
> +{
> + struct nvdimm *nvdimm = to_nvdimm(ndd->dev);
> + struct cxl_pmem_region_params *p = &nvdimm->cxl_region_params;
> + struct nd_namespace_index *nsindex;
> + unsigned long *free;
> + u32 nslot, slot;
> +
> + if (!preamble_current(ndd, &nsindex, &free, &nslot))
> + return 0; /* no label, nothing to preserve */
> +
> + for_each_clear_bit_le(slot, free, nslot) {
> + union nd_lsa_label *lsa_label = to_lsa_label(ndd, slot);
> + struct cxl_region_label *region_label = &lsa_label->region_label;
> + uuid_t *region_uuid = (uuid_t *)®ion_label->type;
Another case where I think we should be importing.
I'm not entirely sure why that's the convention for these but we
should probably stick to it anyway.
> +
> + /* TODO: Currently preserving only one region */
> + if (uuid_equal(&cxl_region_uuid, region_uuid)) {
> + nvdimm->is_region_label = true;
> + import_uuid(&p->uuid, region_label->uuid);
> + p->flags = __le32_to_cpu(region_label->flags);
> + p->nlabel = __le16_to_cpu(region_label->nlabel);
> + p->position = __le16_to_cpu(region_label->position);
> + p->dpa = __le64_to_cpu(region_label->dpa);
> + p->rawsize = __le64_to_cpu(region_label->rawsize);
> + p->hpa = __le64_to_cpu(region_label->hpa);
> + p->slot = __le32_to_cpu(region_label->slot);
> + p->ig = __le32_to_cpu(region_label->ig);
> + p->align = __le32_to_cpu(region_label->align);
> + break;
> + }
> + }
> +
> + return 0;
> +}
^ permalink raw reply [flat|nested] 53+ messages in thread
* Re: [PATCH V5 09/17] nvdimm/label: Export routine to fetch region information
2026-01-09 12:44 ` [PATCH V5 09/17] nvdimm/label: Export routine to fetch region information Neeraj Kumar
@ 2026-01-15 18:03 ` Jonathan Cameron
2026-01-21 0:46 ` Ira Weiny
1 sibling, 0 replies; 53+ messages in thread
From: Jonathan Cameron @ 2026-01-15 18:03 UTC (permalink / raw)
To: Neeraj Kumar
Cc: linux-cxl, nvdimm, linux-kernel, gost.dev, a.manzanares, vishak.g,
neeraj.kernel
On Fri, 9 Jan 2026 18:14:29 +0530
Neeraj Kumar <s.neeraj@samsung.com> wrote:
> CXL region information preserved from the LSA needs to be exported for
> use by the CXL driver for CXL region re-creation.
>
> Reviewed-by: Dave Jiang <dave.jiang@intel.com>
> Signed-off-by: Neeraj Kumar <s.neeraj@samsung.com>
Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>
^ permalink raw reply [flat|nested] 53+ messages in thread
* Re: [PATCH V5 10/17] cxl/mem: Refactor cxl pmem region auto-assembling
2026-01-09 12:44 ` [PATCH V5 10/17] cxl/mem: Refactor cxl pmem region auto-assembling Neeraj Kumar
@ 2026-01-15 18:08 ` Jonathan Cameron
2026-01-23 11:14 ` Neeraj Kumar
0 siblings, 1 reply; 53+ messages in thread
From: Jonathan Cameron @ 2026-01-15 18:08 UTC (permalink / raw)
To: Neeraj Kumar
Cc: linux-cxl, nvdimm, linux-kernel, gost.dev, a.manzanares, vishak.g,
neeraj.kernel
On Fri, 9 Jan 2026 18:14:30 +0530
Neeraj Kumar <s.neeraj@samsung.com> wrote:
> In 84ec985944ef3, devm_cxl_add_nvdimm() sequence was changed and called
> before devm_cxl_add_endpoint(). It's because cxl pmem region auto-assembly
> used to get called at last in cxl_endpoint_port_probe(), which requires
> cxl_nvd presence.
>
> For cxl region persistency, region creation happens during nvdimm_probe
> which need the completion of endpoint probe.
>
> In order to accommodate both cxl pmem region auto-assembly and cxl region
> persistency, refactored following
>
> 1. Re-Sequence devm_cxl_add_nvdimm() after devm_cxl_add_endpoint(). This
> will be called only after successful completion of endpoint probe.
>
> 2. Create cxl_region_discovery() which performs pmem region
> auto-assembly and remove cxl pmem region auto-assembly from
> cxl_endpoint_port_probe()
>
> 3. Register cxl_region_discovery() with devm_cxl_add_memdev() which gets
> called during cxl_pci_probe() in context of cxl_mem_probe()
>
> 4. As cxlmd->ops->probe() calls registered cxl_region_discovery(), so
> move devm_cxl_add_nvdimm() before cxlmd->ops->probe(). It guarantees
> both the completion of endpoint probe and cxl_nvd presence before
> calling cxlmd->ops->probe().
>
> Reviewed-by: Dave Jiang <dave.jiang@intel.com>
> Signed-off-by: Neeraj Kumar <s.neeraj@samsung.com>
One thing below. With that fixes,
Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>
> diff --git a/drivers/cxl/pci.c b/drivers/cxl/pci.c
> index e21051d79b25..d56fdfe4b43b 100644
> --- a/drivers/cxl/pci.c
> +++ b/drivers/cxl/pci.c
> @@ -907,6 +907,7 @@ static int cxl_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
> struct cxl_memdev_state *mds;
> struct cxl_dev_state *cxlds;
> struct cxl_register_map map;
> + struct cxl_memdev_ops ops;
Needs init, as there might be other stuff in there.
struct cxl_memdev_ops ops = {};
> struct cxl_memdev *cxlmd;
> int rc, pmu_count;
> unsigned int i;
> @@ -1006,7 +1007,8 @@ static int cxl_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
> if (rc)
> dev_dbg(&pdev->dev, "No CXL Features discovered\n");
>
> - cxlmd = devm_cxl_add_memdev(&pdev->dev, cxlds, NULL);
> + ops.probe = cxl_region_discovery;
> + cxlmd = devm_cxl_add_memdev(&pdev->dev, cxlds, &ops);
> if (IS_ERR(cxlmd))
> return PTR_ERR(cxlmd);
>
^ permalink raw reply [flat|nested] 53+ messages in thread
* Re: [PATCH V5 11/17] cxl/region: Add devm_cxl_pmem_add_region() for pmem region creation
2026-01-09 12:44 ` [PATCH V5 11/17] cxl/region: Add devm_cxl_pmem_add_region() for pmem region creation Neeraj Kumar
@ 2026-01-15 18:17 ` Jonathan Cameron
2026-01-23 11:17 ` Neeraj Kumar
0 siblings, 1 reply; 53+ messages in thread
From: Jonathan Cameron @ 2026-01-15 18:17 UTC (permalink / raw)
To: Neeraj Kumar
Cc: linux-cxl, nvdimm, linux-kernel, gost.dev, a.manzanares, vishak.g,
neeraj.kernel
On Fri, 9 Jan 2026 18:14:31 +0530
Neeraj Kumar <s.neeraj@samsung.com> wrote:
> devm_cxl_pmem_add_region() is used to create cxl region based on region
> information scanned from LSA.
>
> devm_cxl_add_region() is used to just allocate cxlr and its fields are
> filled later by userspace tool using device attributes (*_store()).
>
> Inspiration for devm_cxl_pmem_add_region() is taken from these device
> attributes (_store*) calls. It allocates cxlr and fills information
> parsed from LSA and calls device_add(&cxlr->dev) to initiate further
> region creation porbes
>
> Rename __create_region() to cxl_create_region(), which will be used
> in later patch to create cxl region after fetching region information
> from LSA.
You also add a couple of parameters. At very least say why here.
>
> Reviewed-by: Dave Jiang <dave.jiang@intel.com>
> Signed-off-by: Neeraj Kumar <s.neeraj@samsung.com>
A few things inline.
> diff --git a/drivers/cxl/core/region.c b/drivers/cxl/core/region.c
> index 26238fb5e8cf..13779aeacd8e 100644
> --- a/drivers/cxl/core/region.c
> +++ b/drivers/cxl/core/region.c
> +static ssize_t alloc_region_dpa(struct cxl_endpoint_decoder *cxled, u64 size)
> +{
> + int rc;
> +
> + if (!size)
> + return -EINVAL;
> +
> + if (!IS_ALIGNED(size, SZ_256M))
> + return -EINVAL;
> +
> + rc = cxl_dpa_free(cxled);
Add a comment on why this make sense. What already allocated dpa that we need
to clean up?
> + if (rc)
> + return rc;
> +
> + return cxl_dpa_alloc(cxled, size);
> +}
> -static struct cxl_region *__create_region(struct cxl_root_decoder *cxlrd,
> - enum cxl_partition_mode mode, int id)
> +struct cxl_region *cxl_create_region(struct cxl_root_decoder *cxlrd,
> + enum cxl_partition_mode mode, int id,
> + struct cxl_pmem_region_params *pmem_params,
> + struct cxl_endpoint_decoder *cxled)
I'm a little dubious that the extra parameters are buried in this patch rather than
where we first need them or a separate patch that makes it clear what they are for.
> {
^ permalink raw reply [flat|nested] 53+ messages in thread
* Re: [PATCH V5 12/17] cxl/pmem: Preserve region information into nd_set
2026-01-09 12:44 ` [PATCH V5 12/17] cxl/pmem: Preserve region information into nd_set Neeraj Kumar
@ 2026-01-15 18:18 ` Jonathan Cameron
0 siblings, 0 replies; 53+ messages in thread
From: Jonathan Cameron @ 2026-01-15 18:18 UTC (permalink / raw)
To: Neeraj Kumar
Cc: linux-cxl, nvdimm, linux-kernel, gost.dev, a.manzanares, vishak.g,
neeraj.kernel
On Fri, 9 Jan 2026 18:14:32 +0530
Neeraj Kumar <s.neeraj@samsung.com> wrote:
> Save region information stored in cxlr to nd_set during
> cxl_pmem_region_probe in nd_set. This saved region information is being
> stored into LSA, which will be used for cxl region persistence
>
> Reviewed-by: Dave Jiang <dave.jiang@intel.com>
> Signed-off-by: Neeraj Kumar <s.neeraj@samsung.com>
Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>
^ permalink raw reply [flat|nested] 53+ messages in thread
* Re: [PATCH V5 14/17] cxl/pmem_region: Introduce CONFIG_CXL_PMEM_REGION for core/pmem_region.c
2026-01-09 12:44 ` [PATCH V5 14/17] cxl/pmem_region: Introduce CONFIG_CXL_PMEM_REGION for core/pmem_region.c Neeraj Kumar
@ 2026-01-15 18:19 ` Jonathan Cameron
0 siblings, 0 replies; 53+ messages in thread
From: Jonathan Cameron @ 2026-01-15 18:19 UTC (permalink / raw)
To: Neeraj Kumar
Cc: linux-cxl, nvdimm, linux-kernel, gost.dev, a.manzanares, vishak.g,
neeraj.kernel
On Fri, 9 Jan 2026 18:14:34 +0530
Neeraj Kumar <s.neeraj@samsung.com> wrote:
> As pmem region label update/delete has hard dependency on libnvdimm.
> It is therefore put core/pmem_region.c under CONFIG_CXL_PMEM_REGION
> control. It handles the dependency by selecting CONFIG_LIBNVDIMM
> if not enabled.
>
> Reviewed-by: Dave Jiang <dave.jiang@intel.com>
> Signed-off-by: Neeraj Kumar <s.neeraj@samsung.com>
Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>
^ permalink raw reply [flat|nested] 53+ messages in thread
* Re: [PATCH V5 15/17] cxl/pmem_region: Add sysfs attribute cxl region label updation/deletion
2026-01-09 12:44 ` [PATCH V5 15/17] cxl/pmem_region: Add sysfs attribute cxl region label updation/deletion Neeraj Kumar
2026-01-14 17:00 ` Dave Jiang
@ 2026-01-15 18:21 ` Jonathan Cameron
2026-01-23 11:25 ` Neeraj Kumar
1 sibling, 1 reply; 53+ messages in thread
From: Jonathan Cameron @ 2026-01-15 18:21 UTC (permalink / raw)
To: Neeraj Kumar
Cc: linux-cxl, nvdimm, linux-kernel, gost.dev, a.manzanares, vishak.g,
neeraj.kernel
On Fri, 9 Jan 2026 18:14:35 +0530
Neeraj Kumar <s.neeraj@samsung.com> wrote:
> Using these attributes region label is added/deleted into LSA. These
> attributes are called from userspace (ndctl) after region creation.
>
> Signed-off-by: Neeraj Kumar <s.neeraj@samsung.com>
One wrong field name.
With that and the version number updated as Dave pointed out
Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>
> diff --git a/drivers/cxl/cxl.h b/drivers/cxl/cxl.h
> index 6ac3b40cb5ff..8c76c4a981bf 100644
> --- a/drivers/cxl/cxl.h
> +++ b/drivers/cxl/cxl.h
> /**
> * struct cxl_region_params - region settings
> * @state: allow the driver to lockdown further parameter changes
> + * @state: region label state
wrong name.
Run scripts/kernel-doc over files you add documentation to and it'll
tell you when you get anything like this wrong.
> * @uuid: unique id for persistent regions
> * @interleave_ways: number of endpoints in the region
> * @interleave_granularity: capacity each endpoint contributes to a stripe
> @@ -488,6 +494,7 @@ enum cxl_config_state {
> */
> struct cxl_region_params {
> enum cxl_config_state state;
> + enum region_label_state state_region_label;
> uuid_t uuid;
> int interleave_ways;
> int interleave_granularity;
^ permalink raw reply [flat|nested] 53+ messages in thread
* Re: [PATCH V5 16/17] cxl/pmem_region: Create pmem region using information parsed from LSA
2026-01-09 12:44 ` [PATCH V5 16/17] cxl/pmem_region: Create pmem region using information parsed from LSA Neeraj Kumar
@ 2026-01-15 18:28 ` Jonathan Cameron
2026-01-23 11:28 ` Neeraj Kumar
0 siblings, 1 reply; 53+ messages in thread
From: Jonathan Cameron @ 2026-01-15 18:28 UTC (permalink / raw)
To: Neeraj Kumar
Cc: linux-cxl, nvdimm, linux-kernel, gost.dev, a.manzanares, vishak.g,
neeraj.kernel
On Fri, 9 Jan 2026 18:14:36 +0530
Neeraj Kumar <s.neeraj@samsung.com> wrote:
> create_pmem_region() creates CXL region based on region information
> parsed from the Label Storage Area (LSA). This routine requires cxl
> endpoint decoder and root decoder. Add cxl_find_root_decoder_by_port()
> and cxl_find_free_ep_decoder() to find the root decoder and a free
> endpoint decoder respectively.
>
> Signed-off-by: Neeraj Kumar <s.neeraj@samsung.com>
Hi Neeraj,
Just a few minor things.
Jonathan
> diff --git a/drivers/cxl/core/pmem_region.c b/drivers/cxl/core/pmem_region.c
> index 53d3d81e9676..4a8cf8322cf0 100644
> --- a/drivers/cxl/core/pmem_region.c
> +++ b/drivers/cxl/core/pmem_region.c
> @@ -287,3 +287,139 @@ int devm_cxl_add_pmem_region(struct cxl_region *cxlr)
> cxlr->cxl_nvb = NULL;
> return rc;
> }
> +
> +static int match_root_decoder_by_dport(struct device *dev, const void *data)
> +{
> + const struct cxl_port *ep_port = data;
> + struct cxl_root_decoder *cxlrd;
> + struct cxl_port *root_port;
> + struct cxl_decoder *cxld;
> + struct cxl_dport *dport;
> + bool dport_matched = false;
> +
> + if (!is_root_decoder(dev))
> + return 0;
> +
> + cxld = to_cxl_decoder(dev);
> + if (!(cxld->flags & CXL_DECODER_F_PMEM))
> + return 0;
> +
> + cxlrd = to_cxl_root_decoder(dev);
> +
> + root_port = cxlrd_to_port(cxlrd);
> + dport = cxl_find_dport_by_dev(root_port, ep_port->host_bridge);
> + if (!dport)
> + return 0;
> +
There is a fairly standard way to check if a loop matched without
needing a boolean. Just check if the exit condition was reached.
drop declaration of i out of here.
> + for (int i = 0; i < cxlrd->cxlsd.nr_targets; i++) {
> + if (dport == cxlrd->cxlsd.target[i]) {
> + dport_matched = true;
No need for this.
> + break;
> + }
> + }
> +
> + if (!dport_matched)
if (i == cxlrd->cxlsd.nr_targets)
return 0;
> + return 0;
> +
> + return is_root_decoder(dev);
> +}
> +
> +/**
> + * cxl_find_root_decoder_by_port() - find a cxl root decoder on cxl bus
> + * @port: any descendant port in CXL port topology
> + * @cxled: endpoint decoder
> + *
> + * Caller of this function must call put_device() when done as a device ref
> + * is taken via device_find_child()
> + */
> +static struct cxl_root_decoder *
> +cxl_find_root_decoder_by_port(struct cxl_port *port,
> + struct cxl_endpoint_decoder *cxled)
> +{
> + struct cxl_root *cxl_root __free(put_cxl_root) = find_cxl_root(port);
> + struct cxl_port *ep_port = cxled_to_port(cxled);
> + struct device *dev;
> +
> + if (!cxl_root)
> + return NULL;
> +
> + dev = device_find_child(&cxl_root->port.dev, ep_port,
> + match_root_decoder_by_dport);
> + if (!dev)
> + return NULL;
> +
> + return to_cxl_root_decoder(dev);
> +}
> +void create_pmem_region(struct nvdimm *nvdimm)
> +{
> + struct cxl_region *cxlr;
> + struct cxl_memdev *cxlmd;
> + struct cxl_nvdimm *cxl_nvd;
> + struct cxl_endpoint_decoder *cxled;
> + struct cxl_pmem_region_params *params;
CXL tends to be reverse xmas tree and good to stick to local style.
> +
> + if (!nvdimm_has_cxl_region(nvdimm))
> + return;
> +
> + lockdep_assert_held(&cxl_rwsem.region);
> + cxl_nvd = nvdimm_provider_data(nvdimm);
> + params = nvdimm_get_cxl_region_param(nvdimm);
> + cxlmd = cxl_nvd->cxlmd;
> +
> + /* TODO: Region creation support only for interleave way == 1 */
> + if (!(params->nlabel == 1)) {
> + dev_dbg(&cxlmd->dev,
> + "Region Creation is not supported with iw > 1\n");
> + return;
> + }
> +
> + struct cxl_decoder *cxld __free(put_cxl_decoder) =
> + cxl_find_free_ep_decoder(cxlmd->endpoint);
> + if (!cxld) {
> + dev_err(&cxlmd->dev, "CXL endpoint decoder not found\n");
> + return;
> + }
> +
> + cxled = to_cxl_endpoint_decoder(&cxld->dev);
> +
> + struct cxl_root_decoder *cxlrd __free(put_cxl_root_decoder) =
> + cxl_find_root_decoder_by_port(cxlmd->endpoint, cxled);
> + if (!cxlrd) {
> + dev_err(&cxlmd->dev, "CXL root decoder not found\n");
> + return;
> + }
> +
> + cxlr = cxl_create_region(cxlrd, CXL_PARTMODE_PMEM,
> + atomic_read(&cxlrd->region_id),
> + params, cxled);
> + if (IS_ERR(cxlr))
> + dev_warn(&cxlmd->dev, "Region Creation failed\n");
> +}
> +EXPORT_SYMBOL_NS_GPL(create_pmem_region, "CXL");
^ permalink raw reply [flat|nested] 53+ messages in thread
* Re: [PATCH V5 17/17] cxl/pmem: Add CXL LSA 2.1 support in cxl pmem
2026-01-09 12:44 ` [PATCH V5 17/17] cxl/pmem: Add CXL LSA 2.1 support in cxl pmem Neeraj Kumar
@ 2026-01-15 18:29 ` Jonathan Cameron
0 siblings, 0 replies; 53+ messages in thread
From: Jonathan Cameron @ 2026-01-15 18:29 UTC (permalink / raw)
To: Neeraj Kumar
Cc: linux-cxl, nvdimm, linux-kernel, gost.dev, a.manzanares, vishak.g,
neeraj.kernel
On Fri, 9 Jan 2026 18:14:37 +0530
Neeraj Kumar <s.neeraj@samsung.com> wrote:
> Add support of CXL LSA 2.1 using NDD_REGION_LABELING flag. It creates
> cxl region based on region information parsed from LSA
>
> Reviewed-by: Dave Jiang <dave.jiang@intel.com>
> Signed-off-by: Neeraj Kumar <s.neeraj@samsung.com>
Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>
^ permalink raw reply [flat|nested] 53+ messages in thread
* Re: [PATCH V5 03/17] nvdimm/label: Add namespace/region label support as per LSA 2.1
2026-01-09 12:44 ` [PATCH V5 03/17] nvdimm/label: Add namespace/region label support as per LSA 2.1 Neeraj Kumar
2026-01-15 17:45 ` Jonathan Cameron
@ 2026-01-21 0:35 ` Ira Weiny
1 sibling, 0 replies; 53+ messages in thread
From: Ira Weiny @ 2026-01-21 0:35 UTC (permalink / raw)
To: Neeraj Kumar, linux-cxl, nvdimm, linux-kernel, gost.dev
Cc: a.manzanares, vishak.g, neeraj.kernel, Neeraj Kumar
Neeraj Kumar wrote:
> Modify __pmem_label_update() to update region labels into LSA
>
> CXL 3.2 Spec mentions CXL LSA 2.1 Namespace Labels at section 9.13.2.5
> Modified __pmem_label_update() using setter functions to update
> namespace label as per CXL LSA 2.1
>
> Create export routine nd_region_label_update() used for creating
> region label into LSA. It will be used later from CXL subsystem
>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
[snip]
^ permalink raw reply [flat|nested] 53+ messages in thread
* Re: [PATCH V5 04/17] nvdimm/label: Include region label in slot validation
2026-01-09 12:44 ` [PATCH V5 04/17] nvdimm/label: Include region label in slot validation Neeraj Kumar
2026-01-14 21:20 ` Ira Weiny
2026-01-15 17:55 ` Jonathan Cameron
@ 2026-01-21 0:38 ` Ira Weiny
2 siblings, 0 replies; 53+ messages in thread
From: Ira Weiny @ 2026-01-21 0:38 UTC (permalink / raw)
To: Neeraj Kumar, linux-cxl, nvdimm, linux-kernel, gost.dev
Cc: a.manzanares, vishak.g, neeraj.kernel, Neeraj Kumar
Neeraj Kumar wrote:
> Prior to LSA 2.1 Support, label in slot means only namespace
> label. But with LSA 2.1 a label can be either namespace or
> region label.
>
> Slot validation routine validates label slot by calculating
> label checksum. It was only validating namespace label.
> This changeset also validates region label if present.
>
> In previous patch to_lsa_label() was introduced along with
> to_label(). to_label() returns only namespace label whereas
> to_lsa_label() returns union nd_lsa_label*
>
> In this patch We have converted all usage of to_label()
> to to_lsa_label()
>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
[snip]
^ permalink raw reply [flat|nested] 53+ messages in thread
* Re: [PATCH V5 05/17] nvdimm/label: Skip region label during ns label DPA reservation
2026-01-09 12:44 ` [PATCH V5 05/17] nvdimm/label: Skip region label during ns label DPA reservation Neeraj Kumar
2026-01-15 17:56 ` Jonathan Cameron
@ 2026-01-21 0:41 ` Ira Weiny
2026-01-23 11:05 ` Neeraj Kumar
1 sibling, 1 reply; 53+ messages in thread
From: Ira Weiny @ 2026-01-21 0:41 UTC (permalink / raw)
To: Neeraj Kumar, linux-cxl, nvdimm, linux-kernel, gost.dev
Cc: a.manzanares, vishak.g, neeraj.kernel, Neeraj Kumar
Neeraj Kumar wrote:
> CXL 3.2 Spec mentions CXL LSA 2.1 Namespace Labels at section
> 9.13.2.5. If Namespace label is present in LSA during
> nvdimm_probe() then dimm-physical-address(DPA) reservation is
> required. But this reservation is not required by cxl region
> label. Therefore if LSA scanning finds any region label, skip it.
>
> Reviewed-by: Dave Jiang <dave.jiang@intel.com>
> Signed-off-by: Neeraj Kumar <s.neeraj@samsung.com>
> ---
> drivers/nvdimm/label.c | 8 ++++++++
> 1 file changed, 8 insertions(+)
>
> diff --git a/drivers/nvdimm/label.c b/drivers/nvdimm/label.c
> index 9854cb45fb62..169692dfa12c 100644
> --- a/drivers/nvdimm/label.c
> +++ b/drivers/nvdimm/label.c
> @@ -469,6 +469,14 @@ int nd_label_reserve_dpa(struct nvdimm_drvdata *ndd)
> lsa_label = to_lsa_label(ndd, slot);
> nd_label = &lsa_label->ns_label;
>
> + /*
> + * Skip region label. If LSA label is region label
^^^^^^^^^^^^^^^^^^
This is redundant
> + * then it don't require dimm-physical-address(DPA)
^^^^^
doesn't
> + * reservation. Whereas its required for namespace label
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
This is somewhat confusing and redundant
as well.
Simply say.
/*
* If the LSA label is a region label then it doesn't require a
* dimm-physical-address(DPA) reservation.
*/
With that.
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
> + if (is_region_label(ndd, lsa_label))
> + continue;
> +
> if (!slot_valid(ndd, lsa_label, slot))
> continue;
>
> --
> 2.34.1
>
>
^ permalink raw reply [flat|nested] 53+ messages in thread
* Re: [PATCH V5 06/17] nvdimm/label: Preserve region label during namespace creation
2026-01-09 12:44 ` [PATCH V5 06/17] nvdimm/label: Preserve region label during namespace creation Neeraj Kumar
2026-01-15 17:59 ` Jonathan Cameron
@ 2026-01-21 0:43 ` Ira Weiny
1 sibling, 0 replies; 53+ messages in thread
From: Ira Weiny @ 2026-01-21 0:43 UTC (permalink / raw)
To: Neeraj Kumar, linux-cxl, nvdimm, linux-kernel, gost.dev
Cc: a.manzanares, vishak.g, neeraj.kernel, Neeraj Kumar
Neeraj Kumar wrote:
> During namespace creation we scan labels present in LSA using
> scan_labels(). Currently scan_labels() is only preserving
> namespace labels into label_ent list.
>
> In this patch we also preserve region label into label_ent list
>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
[snip]
^ permalink raw reply [flat|nested] 53+ messages in thread
* Re: [PATCH V5 07/17] nvdimm/label: Add region label delete support
2026-01-09 12:44 ` [PATCH V5 07/17] nvdimm/label: Add region label delete support Neeraj Kumar
@ 2026-01-21 0:44 ` Ira Weiny
0 siblings, 0 replies; 53+ messages in thread
From: Ira Weiny @ 2026-01-21 0:44 UTC (permalink / raw)
To: Neeraj Kumar, linux-cxl, nvdimm, linux-kernel, gost.dev
Cc: a.manzanares, vishak.g, neeraj.kernel, Neeraj Kumar
Neeraj Kumar wrote:
> Create export routine nd_region_label_delete() used for deleting
> region label from LSA. It will be used later from CXL subsystem
>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
[snip]
^ permalink raw reply [flat|nested] 53+ messages in thread
* Re: [PATCH V5 08/17] nvdimm/label: Preserve cxl region information from region label
2026-01-09 12:44 ` [PATCH V5 08/17] nvdimm/label: Preserve cxl region information from region label Neeraj Kumar
2026-01-15 18:03 ` Jonathan Cameron
@ 2026-01-21 0:45 ` Ira Weiny
1 sibling, 0 replies; 53+ messages in thread
From: Ira Weiny @ 2026-01-21 0:45 UTC (permalink / raw)
To: Neeraj Kumar, linux-cxl, nvdimm, linux-kernel, gost.dev
Cc: a.manzanares, vishak.g, neeraj.kernel, Neeraj Kumar
Neeraj Kumar wrote:
> Preserve region information from region label during nvdimm_probe. This
> preserved region information is used for creating cxl region to achieve
> region persistency across reboot.
> This patch supports interleave way == 1, it is therefore it preserves
> only one region into LSA
>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
[snip]
^ permalink raw reply [flat|nested] 53+ messages in thread
* Re: [PATCH V5 09/17] nvdimm/label: Export routine to fetch region information
2026-01-09 12:44 ` [PATCH V5 09/17] nvdimm/label: Export routine to fetch region information Neeraj Kumar
2026-01-15 18:03 ` Jonathan Cameron
@ 2026-01-21 0:46 ` Ira Weiny
2026-01-23 11:11 ` Neeraj Kumar
2026-01-23 11:20 ` Neeraj Kumar
1 sibling, 2 replies; 53+ messages in thread
From: Ira Weiny @ 2026-01-21 0:46 UTC (permalink / raw)
To: Neeraj Kumar, linux-cxl, nvdimm, linux-kernel, gost.dev
Cc: a.manzanares, vishak.g, neeraj.kernel, Neeraj Kumar
Neeraj Kumar wrote:
> CXL region information preserved from the LSA needs to be exported for
> use by the CXL driver for CXL region re-creation.
>
Some of the CXL tree patches did not apply cleanly to cxl/next.
Up to this point I ran the nvdimm tests which showed that none of this
broken existing functionality.
Will there be additional nvdimm tests for this?
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
[snip]
^ permalink raw reply [flat|nested] 53+ messages in thread
* Re: [PATCH V5 00/17] Add CXL LSA 2.1 format support in nvdimm and cxl pmem
2026-01-09 12:44 ` [PATCH V5 00/17] Add CXL LSA 2.1 format support in nvdimm and cxl pmem Neeraj Kumar
` (16 preceding siblings ...)
2026-01-09 12:44 ` [PATCH V5 17/17] cxl/pmem: Add CXL LSA 2.1 support in cxl pmem Neeraj Kumar
@ 2026-01-21 15:37 ` Dave Jiang
17 siblings, 0 replies; 53+ messages in thread
From: Dave Jiang @ 2026-01-21 15:37 UTC (permalink / raw)
To: Neeraj Kumar, linux-cxl, nvdimm, linux-kernel, gost.dev
Cc: a.manzanares, vishak.g, neeraj.kernel
On 1/9/26 5:44 AM, Neeraj Kumar wrote:
<snip>
>
> base-commit: fa19611f96fd8573c826d61a1e9410938a581bf3
> prerequisite-patch-id: f6e07504b17ccf39d9486352b6f7305a03897863
> prerequisite-patch-id: cd6bad0c8b993bb59369941905f418f3b799c89d
> prerequisite-patch-id: 08ebdae0888c0a2631c3b26990679a0261f34f14
> prerequisite-patch-id: 344220faa9c156afec0f5d866ad3098880a85e34
For the next rev, please rebase against for-7.0/cxl-init branch (unless 7.0-rc1 has dropped). Thanks!
^ permalink raw reply [flat|nested] 53+ messages in thread
* Re: [PATCH V5 03/17] nvdimm/label: Add namespace/region label support as per LSA 2.1
2026-01-15 17:45 ` Jonathan Cameron
@ 2026-01-23 10:57 ` Neeraj Kumar
0 siblings, 0 replies; 53+ messages in thread
From: Neeraj Kumar @ 2026-01-23 10:57 UTC (permalink / raw)
To: Jonathan Cameron
Cc: linux-cxl, nvdimm, linux-kernel, gost.dev, a.manzanares, vishak.g,
neeraj.kernel, cpgs
[-- Attachment #1: Type: text/plain, Size: 2687 bytes --]
On 15/01/26 05:45PM, Jonathan Cameron wrote:
>On Fri, 9 Jan 2026 18:14:23 +0530
>Neeraj Kumar <s.neeraj@samsung.com> wrote:
>
>> Modify __pmem_label_update() to update region labels into LSA
>>
>> CXL 3.2 Spec mentions CXL LSA 2.1 Namespace Labels at section 9.13.2.5
>> Modified __pmem_label_update() using setter functions to update
>> namespace label as per CXL LSA 2.1
>>
>> Create export routine nd_region_label_update() used for creating
>> region label into LSA. It will be used later from CXL subsystem
>>
>> Reviewed-by: Dave Jiang <dave.jiang@intel.com>
>> Signed-off-by: Neeraj Kumar <s.neeraj@samsung.com>
>
>Hi Neeraj,
>
>There are a few more instances of copying in and out of UUIDs that
>should be using the import and export functions.
>
>With those fixed up,
>Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>
>
>> ---
>> drivers/nvdimm/label.c | 360 ++++++++++++++++++++++++++------
>> drivers/nvdimm/label.h | 17 +-
>> drivers/nvdimm/namespace_devs.c | 20 +-
>> drivers/nvdimm/nd.h | 51 +++++
>> include/linux/libnvdimm.h | 8 +
>> 5 files changed, 386 insertions(+), 70 deletions(-)
>>
>> diff --git a/drivers/nvdimm/label.c b/drivers/nvdimm/label.c
>> index 0a9b6c5cb2c3..17e2a1f5a6da 100644
>> --- a/drivers/nvdimm/label.c
>> +++ b/drivers/nvdimm/label.c
>
>
>> +static void region_label_update(struct nd_region *nd_region,
>> + struct cxl_region_label *region_label,
>> + struct nd_mapping *nd_mapping,
>> + int pos, u64 flags, u32 slot)
>> +{
>> + struct nd_interleave_set *nd_set = nd_region->nd_set;
>> + struct nvdimm_drvdata *ndd = to_ndd(nd_mapping);
>> +
>> + /* Set Region Label Format identification UUID */
>> + uuid_copy((uuid_t *)region_label->type, &cxl_region_uuid);
>
>
>Why is this one not an export_uuid()?
Yes I have used it to avoid extra typecasting in v6
>
>
>> +
>> +static inline bool is_region_label(struct nvdimm_drvdata *ndd,
>> + union nd_lsa_label *lsa_label)
>> +{
>> + if (!ndd->cxl)
>> + return false;
>> +
>> + return uuid_equal(&cxl_region_uuid,
>> + (uuid_t *)lsa_label->region_label.type);
>As below.
>> +}
>> +
>> +static inline bool
>> +region_label_uuid_equal(struct cxl_region_label *region_label,
>> + const uuid_t *uuid)
>> +{
>> + return uuid_equal((uuid_t *)region_label->uuid, uuid);
>
>Not appropriate to do an import_uuid() for this and similar cases?
>In general I don't think we should see any casts to uuid_t *
>
>There are 3 instances of this in the kernel and we should probably clean
>all those up. There are a lot more doing the import!
I have used import_uuid() accordingly in v6 and will be sending it soon
Regards,
Neeraj
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^ permalink raw reply [flat|nested] 53+ messages in thread
* Re: [PATCH V5 04/17] nvdimm/label: Include region label in slot validation
2026-01-14 21:20 ` Ira Weiny
@ 2026-01-23 11:02 ` Neeraj Kumar
0 siblings, 0 replies; 53+ messages in thread
From: Neeraj Kumar @ 2026-01-23 11:02 UTC (permalink / raw)
To: Ira Weiny
Cc: linux-cxl, nvdimm, linux-kernel, gost.dev, a.manzanares, vishak.g,
neeraj.kernel, cpgs
[-- Attachment #1: Type: text/plain, Size: 2990 bytes --]
On 14/01/26 03:20PM, Ira Weiny wrote:
>Neeraj Kumar wrote:
>> Prior to LSA 2.1 Support, label in slot means only namespace
>> label. But with LSA 2.1 a label can be either namespace or
>> region label.
>>
>> Slot validation routine validates label slot by calculating
>> label checksum. It was only validating namespace label.
>> This changeset also validates region label if present.
>>
>> In previous patch to_lsa_label() was introduced along with
>> to_label(). to_label() returns only namespace label whereas
>> to_lsa_label() returns union nd_lsa_label*
>>
>> In this patch We have converted all usage of to_label()
>
>NIT: don't use 'We'
Fixed it in V6
>
>> to to_lsa_label()
>>
>> Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>
>> Reviewed-by: Dave Jiang <dave.jiang@intel.com>
>> Signed-off-by: Neeraj Kumar <s.neeraj@samsung.com>
>> ---
>> drivers/nvdimm/label.c | 94 ++++++++++++++++++++++++++++--------------
>> 1 file changed, 64 insertions(+), 30 deletions(-)
>>
>> diff --git a/drivers/nvdimm/label.c b/drivers/nvdimm/label.c
>> index 17e2a1f5a6da..9854cb45fb62 100644
>> --- a/drivers/nvdimm/label.c
>> +++ b/drivers/nvdimm/label.c
>> @@ -312,16 +312,6 @@ static union nd_lsa_label *to_lsa_label(struct nvdimm_drvdata *ndd, int slot)
>> return (union nd_lsa_label *) label;
>> }
>>
>> -static struct nd_namespace_label *to_label(struct nvdimm_drvdata *ndd, int slot)
>> -{
>> - unsigned long label, base;
>> -
>> - base = (unsigned long) nd_label_base(ndd);
>> - label = base + sizeof_namespace_label(ndd) * slot;
>> -
>> - return (struct nd_namespace_label *) label;
>> -}
>> -
>> #define for_each_clear_bit_le(bit, addr, size) \
>> for ((bit) = find_next_zero_bit_le((addr), (size), 0); \
>> (bit) < (size); \
>> @@ -382,7 +372,7 @@ static bool nsl_validate_checksum(struct nvdimm_drvdata *ndd,
>> {
>> u64 sum, sum_save;
>>
>> - if (!ndd->cxl && !efi_namespace_label_has(ndd, checksum))
>> + if (!efi_namespace_label_has(ndd, checksum))
>
>What does this change have to do with region label validation during slot
>validation?
>
>> return true;
>>
>> sum_save = nsl_get_checksum(ndd, nd_label);
>> @@ -397,13 +387,25 @@ static void nsl_calculate_checksum(struct nvdimm_drvdata *ndd,
>> {
>> u64 sum;
>>
>> - if (!ndd->cxl && !efi_namespace_label_has(ndd, checksum))
>> + if (!efi_namespace_label_has(ndd, checksum))
>
>This and the above seem like cleanups because efi_namespace_label_has()
>already checks !ndd->cxl? Was that the intent? Perhaps as a separate
>cleanup?
Hi Ira,
Actually above is required changes and not the cleanup.
Earlier condition (!ndd->cxl && !efi_namespace_label_has(ndd, checksum))
was getting true (no further processing) in first case only if its a
region label which we don't want in current case.
And this condition (!efi_namespace_label_has(ndd, checksum)) returns false
(means proceed further) in case if its a region label (!!ndd->cxl).
Regards,
Neeraj
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^ permalink raw reply [flat|nested] 53+ messages in thread
* Re: [PATCH V5 05/17] nvdimm/label: Skip region label during ns label DPA reservation
2026-01-21 0:41 ` Ira Weiny
@ 2026-01-23 11:05 ` Neeraj Kumar
0 siblings, 0 replies; 53+ messages in thread
From: Neeraj Kumar @ 2026-01-23 11:05 UTC (permalink / raw)
To: Ira Weiny
Cc: linux-cxl, nvdimm, linux-kernel, gost.dev, a.manzanares, vishak.g,
neeraj.kernel, cpgs
[-- Attachment #1: Type: text/plain, Size: 1601 bytes --]
On 20/01/26 06:41PM, Ira Weiny wrote:
>Neeraj Kumar wrote:
>> CXL 3.2 Spec mentions CXL LSA 2.1 Namespace Labels at section
>> 9.13.2.5. If Namespace label is present in LSA during
>> nvdimm_probe() then dimm-physical-address(DPA) reservation is
>> required. But this reservation is not required by cxl region
>> label. Therefore if LSA scanning finds any region label, skip it.
>>
>> Reviewed-by: Dave Jiang <dave.jiang@intel.com>
>> Signed-off-by: Neeraj Kumar <s.neeraj@samsung.com>
>> ---
>> drivers/nvdimm/label.c | 8 ++++++++
>> 1 file changed, 8 insertions(+)
>>
>> diff --git a/drivers/nvdimm/label.c b/drivers/nvdimm/label.c
>> index 9854cb45fb62..169692dfa12c 100644
>> --- a/drivers/nvdimm/label.c
>> +++ b/drivers/nvdimm/label.c
>> @@ -469,6 +469,14 @@ int nd_label_reserve_dpa(struct nvdimm_drvdata *ndd)
>> lsa_label = to_lsa_label(ndd, slot);
>> nd_label = &lsa_label->ns_label;
>>
>> + /*
>> + * Skip region label. If LSA label is region label
> ^^^^^^^^^^^^^^^^^^
> This is redundant
>> + * then it don't require dimm-physical-address(DPA)
> ^^^^^
> doesn't
>
>> + * reservation. Whereas its required for namespace label
> ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
> This is somewhat confusing and redundant
> as well.
>
>Simply say.
>
> /*
> * If the LSA label is a region label then it doesn't require a
> * dimm-physical-address(DPA) reservation.
> */
>
>With that.
Fixed it accordingly in V6
>
>Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Thanks Ira.
Regards,
Neeraj
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^ permalink raw reply [flat|nested] 53+ messages in thread
* Re: [PATCH V5 08/17] nvdimm/label: Preserve cxl region information from region label
2026-01-15 18:03 ` Jonathan Cameron
@ 2026-01-23 11:08 ` Neeraj Kumar
0 siblings, 0 replies; 53+ messages in thread
From: Neeraj Kumar @ 2026-01-23 11:08 UTC (permalink / raw)
To: Jonathan Cameron
Cc: linux-cxl, nvdimm, linux-kernel, gost.dev, a.manzanares, vishak.g,
neeraj.kernel, cpgs
[-- Attachment #1: Type: text/plain, Size: 1777 bytes --]
On 15/01/26 06:03PM, Jonathan Cameron wrote:
>On Fri, 9 Jan 2026 18:14:28 +0530
>Neeraj Kumar <s.neeraj@samsung.com> wrote:
>
>> Preserve region information from region label during nvdimm_probe. This
>> preserved region information is used for creating cxl region to achieve
>> region persistency across reboot.
>> This patch supports interleave way == 1, it is therefore it preserves
>> only one region into LSA
>>
>> Reviewed-by: Dave Jiang <dave.jiang@intel.com>
>> Signed-off-by: Neeraj Kumar <s.neeraj@samsung.com>
>
>With change to import for getting the region uuid,
>Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>
>
>> diff --git a/drivers/nvdimm/label.c b/drivers/nvdimm/label.c
>> index 2ad148bfe40b..7adb415f0926 100644
>> --- a/drivers/nvdimm/label.c
>> +++ b/drivers/nvdimm/label.c
>> @@ -494,6 +494,42 @@ int nd_label_reserve_dpa(struct nvdimm_drvdata *ndd)
>> return 0;
>> }
>>
>> +int nvdimm_cxl_region_preserve(struct nvdimm_drvdata *ndd)
>> +{
>> + struct nvdimm *nvdimm = to_nvdimm(ndd->dev);
>> + struct cxl_pmem_region_params *p = &nvdimm->cxl_region_params;
>> + struct nd_namespace_index *nsindex;
>> + unsigned long *free;
>> + u32 nslot, slot;
>> +
>> + if (!preamble_current(ndd, &nsindex, &free, &nslot))
>> + return 0; /* no label, nothing to preserve */
>> +
>> + for_each_clear_bit_le(slot, free, nslot) {
>> + union nd_lsa_label *lsa_label = to_lsa_label(ndd, slot);
>> + struct cxl_region_label *region_label = &lsa_label->region_label;
>> + uuid_t *region_uuid = (uuid_t *)®ion_label->type;
>
>Another case where I think we should be importing.
>I'm not entirely sure why that's the convention for these but we
>should probably stick to it anyway.
>
Fixed it accordingly. Thanks Jonathan for RB tag
Regards,
Neeraj
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^ permalink raw reply [flat|nested] 53+ messages in thread
* Re: [PATCH V5 09/17] nvdimm/label: Export routine to fetch region information
2026-01-21 0:46 ` Ira Weiny
@ 2026-01-23 11:11 ` Neeraj Kumar
2026-01-23 11:20 ` Neeraj Kumar
1 sibling, 0 replies; 53+ messages in thread
From: Neeraj Kumar @ 2026-01-23 11:11 UTC (permalink / raw)
To: Ira Weiny
Cc: linux-cxl, nvdimm, linux-kernel, gost.dev, a.manzanares, vishak.g,
neeraj.kernel, cpgs
[-- Attachment #1: Type: text/plain, Size: 625 bytes --]
On 20/01/26 06:46PM, Ira Weiny wrote:
>Neeraj Kumar wrote:
>> CXL region information preserved from the LSA needs to be exported for
>> use by the CXL driver for CXL region re-creation.
>>
>
>Some of the CXL tree patches did not apply cleanly to cxl/next.
>
>Up to this point I ran the nvdimm tests which showed that none of this
>broken existing functionality.
>
>Will there be additional nvdimm tests for this?
No I have not added any additional test for this.
This is tested using qemu and mentioned its procedure in cover letter
>
>Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Thanks Ira for RB tag.
Regards,
Neeraj
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^ permalink raw reply [flat|nested] 53+ messages in thread
* Re: [PATCH V5 10/17] cxl/mem: Refactor cxl pmem region auto-assembling
2026-01-15 18:08 ` Jonathan Cameron
@ 2026-01-23 11:14 ` Neeraj Kumar
0 siblings, 0 replies; 53+ messages in thread
From: Neeraj Kumar @ 2026-01-23 11:14 UTC (permalink / raw)
To: Jonathan Cameron
Cc: linux-cxl, nvdimm, linux-kernel, gost.dev, a.manzanares, vishak.g,
neeraj.kernel, cpgs
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On 15/01/26 06:08PM, Jonathan Cameron wrote:
>On Fri, 9 Jan 2026 18:14:30 +0530
>Neeraj Kumar <s.neeraj@samsung.com> wrote:
>
>> In 84ec985944ef3, devm_cxl_add_nvdimm() sequence was changed and called
>> before devm_cxl_add_endpoint(). It's because cxl pmem region auto-assembly
>> used to get called at last in cxl_endpoint_port_probe(), which requires
>> cxl_nvd presence.
>>
>> For cxl region persistency, region creation happens during nvdimm_probe
>> which need the completion of endpoint probe.
>>
>> In order to accommodate both cxl pmem region auto-assembly and cxl region
>> persistency, refactored following
>>
>> 1. Re-Sequence devm_cxl_add_nvdimm() after devm_cxl_add_endpoint(). This
>> will be called only after successful completion of endpoint probe.
>>
>> 2. Create cxl_region_discovery() which performs pmem region
>> auto-assembly and remove cxl pmem region auto-assembly from
>> cxl_endpoint_port_probe()
>>
>> 3. Register cxl_region_discovery() with devm_cxl_add_memdev() which gets
>> called during cxl_pci_probe() in context of cxl_mem_probe()
>>
>> 4. As cxlmd->ops->probe() calls registered cxl_region_discovery(), so
>> move devm_cxl_add_nvdimm() before cxlmd->ops->probe(). It guarantees
>> both the completion of endpoint probe and cxl_nvd presence before
>> calling cxlmd->ops->probe().
>>
>> Reviewed-by: Dave Jiang <dave.jiang@intel.com>
>> Signed-off-by: Neeraj Kumar <s.neeraj@samsung.com>
>
>One thing below. With that fixes,
>Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>
Thanks Jonathan for RB tag
>
>
>> diff --git a/drivers/cxl/pci.c b/drivers/cxl/pci.c
>> index e21051d79b25..d56fdfe4b43b 100644
>> --- a/drivers/cxl/pci.c
>> +++ b/drivers/cxl/pci.c
>> @@ -907,6 +907,7 @@ static int cxl_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
>> struct cxl_memdev_state *mds;
>> struct cxl_dev_state *cxlds;
>> struct cxl_register_map map;
>> + struct cxl_memdev_ops ops;
>
>Needs init, as there might be other stuff in there.
> struct cxl_memdev_ops ops = {};
Now cxl_memdev_ops is changed with cxl_memdev_attach.
I have initialized it accordingly.
Regards,
Neeraj
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* Re: [PATCH V5 11/17] cxl/region: Add devm_cxl_pmem_add_region() for pmem region creation
2026-01-15 18:17 ` Jonathan Cameron
@ 2026-01-23 11:17 ` Neeraj Kumar
0 siblings, 0 replies; 53+ messages in thread
From: Neeraj Kumar @ 2026-01-23 11:17 UTC (permalink / raw)
To: Jonathan Cameron
Cc: linux-cxl, nvdimm, linux-kernel, gost.dev, a.manzanares, vishak.g,
neeraj.kernel, cpgs
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On 15/01/26 06:17PM, Jonathan Cameron wrote:
>On Fri, 9 Jan 2026 18:14:31 +0530
>Neeraj Kumar <s.neeraj@samsung.com> wrote:
>
>> devm_cxl_pmem_add_region() is used to create cxl region based on region
>> information scanned from LSA.
>>
>> devm_cxl_add_region() is used to just allocate cxlr and its fields are
>> filled later by userspace tool using device attributes (*_store()).
>>
>> Inspiration for devm_cxl_pmem_add_region() is taken from these device
>> attributes (_store*) calls. It allocates cxlr and fills information
>> parsed from LSA and calls device_add(&cxlr->dev) to initiate further
>> region creation porbes
>>
>> Rename __create_region() to cxl_create_region(), which will be used
>> in later patch to create cxl region after fetching region information
>> from LSA.
>You also add a couple of parameters. At very least say why here.
Not required now, I have created a separate patch for this.
>
>>
>> Reviewed-by: Dave Jiang <dave.jiang@intel.com>
>> Signed-off-by: Neeraj Kumar <s.neeraj@samsung.com>
>
>A few things inline.
>
>> diff --git a/drivers/cxl/core/region.c b/drivers/cxl/core/region.c
>> index 26238fb5e8cf..13779aeacd8e 100644
>> --- a/drivers/cxl/core/region.c
>> +++ b/drivers/cxl/core/region.c
>
>
>> +static ssize_t alloc_region_dpa(struct cxl_endpoint_decoder *cxled, u64 size)
>> +{
>> + int rc;
>> +
>> + if (!size)
>> + return -EINVAL;
>> +
>> + if (!IS_ALIGNED(size, SZ_256M))
>> + return -EINVAL;
>> +
>> + rc = cxl_dpa_free(cxled);
>
>Add a comment on why this make sense. What already allocated dpa that we need
>to clean up?
Inspiration of alloc_region_dpa() is taken from size_store(). But yes here its not
required. I have removed it accordingly in V6
>
>> + if (rc)
>> + return rc;
>> +
>> + return cxl_dpa_alloc(cxled, size);
>> +}
>
>
>> -static struct cxl_region *__create_region(struct cxl_root_decoder *cxlrd,
>> - enum cxl_partition_mode mode, int id)
>> +struct cxl_region *cxl_create_region(struct cxl_root_decoder *cxlrd,
>> + enum cxl_partition_mode mode, int id,
>> + struct cxl_pmem_region_params *pmem_params,
>> + struct cxl_endpoint_decoder *cxled)
>
>I'm a little dubious that the extra parameters are buried in this patch rather than
>where we first need them or a separate patch that makes it clear what they are for.
Yes I have separated it out in V6.
Regards,
Neeraj
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^ permalink raw reply [flat|nested] 53+ messages in thread
* Re: [PATCH V5 09/17] nvdimm/label: Export routine to fetch region information
2026-01-21 0:46 ` Ira Weiny
2026-01-23 11:11 ` Neeraj Kumar
@ 2026-01-23 11:20 ` Neeraj Kumar
1 sibling, 0 replies; 53+ messages in thread
From: Neeraj Kumar @ 2026-01-23 11:20 UTC (permalink / raw)
To: Ira Weiny
Cc: linux-cxl, nvdimm, linux-kernel, gost.dev, a.manzanares, vishak.g,
neeraj.kernel, cpgs
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On 20/01/26 06:46PM, Ira Weiny wrote:
>Neeraj Kumar wrote:
>> CXL region information preserved from the LSA needs to be exported for
>> use by the CXL driver for CXL region re-creation.
>>
>
>Some of the CXL tree patches did not apply cleanly to cxl/next.
I have rebased V6 with for-7.0/cxl-init. Can you please check with V6.
Regards,
Neeraj
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^ permalink raw reply [flat|nested] 53+ messages in thread
* Re: [PATCH V5 15/17] cxl/pmem_region: Add sysfs attribute cxl region label updation/deletion
2026-01-14 17:00 ` Dave Jiang
@ 2026-01-23 11:22 ` Neeraj Kumar
0 siblings, 0 replies; 53+ messages in thread
From: Neeraj Kumar @ 2026-01-23 11:22 UTC (permalink / raw)
To: Dave Jiang
Cc: linux-cxl, nvdimm, linux-kernel, gost.dev, a.manzanares, vishak.g,
neeraj.kernel, cpgs
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On 14/01/26 10:00AM, Dave Jiang wrote:
>
>
>On 1/9/26 5:44 AM, Neeraj Kumar wrote:
>> Using these attributes region label is added/deleted into LSA. These
>> attributes are called from userspace (ndctl) after region creation.
>>
>> Signed-off-by: Neeraj Kumar <s.neeraj@samsung.com>
>
>Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Thanks Dave for RB tag.
>
>You'll need to update the KernelVersion to v7.0.
Fixed it in V6.
Regards,
Neeraj
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^ permalink raw reply [flat|nested] 53+ messages in thread
* Re: [PATCH V5 15/17] cxl/pmem_region: Add sysfs attribute cxl region label updation/deletion
2026-01-15 18:21 ` Jonathan Cameron
@ 2026-01-23 11:25 ` Neeraj Kumar
0 siblings, 0 replies; 53+ messages in thread
From: Neeraj Kumar @ 2026-01-23 11:25 UTC (permalink / raw)
To: Jonathan Cameron
Cc: linux-cxl, nvdimm, linux-kernel, gost.dev, a.manzanares, vishak.g,
neeraj.kernel, cpgs
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On 15/01/26 06:21PM, Jonathan Cameron wrote:
>On Fri, 9 Jan 2026 18:14:35 +0530
>Neeraj Kumar <s.neeraj@samsung.com> wrote:
>
>> Using these attributes region label is added/deleted into LSA. These
>> attributes are called from userspace (ndctl) after region creation.
>>
>> Signed-off-by: Neeraj Kumar <s.neeraj@samsung.com>
>One wrong field name.
>
>With that and the version number updated as Dave pointed out
>Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>
Thanks Jonathan for RB tag.
>
>
>> diff --git a/drivers/cxl/cxl.h b/drivers/cxl/cxl.h
>> index 6ac3b40cb5ff..8c76c4a981bf 100644
>> --- a/drivers/cxl/cxl.h
>> +++ b/drivers/cxl/cxl.h
>
>> /**
>> * struct cxl_region_params - region settings
>> * @state: allow the driver to lockdown further parameter changes
>> + * @state: region label state
>
>wrong name.
Fixed it in V6
>
>Run scripts/kernel-doc over files you add documentation to and it'll
>tell you when you get anything like this wrong.
I ran it but its not showing any error and displaying the wrong name
only.
Regards,
Neeraj
>
>> * @uuid: unique id for persistent regions
>> * @interleave_ways: number of endpoints in the region
>> * @interleave_granularity: capacity each endpoint contributes to a stripe
>> @@ -488,6 +494,7 @@ enum cxl_config_state {
>> */
>> struct cxl_region_params {
>> enum cxl_config_state state;
>> + enum region_label_state state_region_label;
>> uuid_t uuid;
>> int interleave_ways;
>> int interleave_granularity;
>
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^ permalink raw reply [flat|nested] 53+ messages in thread
* Re: [PATCH V5 16/17] cxl/pmem_region: Create pmem region using information parsed from LSA
2026-01-15 18:28 ` Jonathan Cameron
@ 2026-01-23 11:28 ` Neeraj Kumar
0 siblings, 0 replies; 53+ messages in thread
From: Neeraj Kumar @ 2026-01-23 11:28 UTC (permalink / raw)
To: Jonathan Cameron
Cc: linux-cxl, nvdimm, linux-kernel, gost.dev, a.manzanares, vishak.g,
neeraj.kernel, cpgs
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On 15/01/26 06:28PM, Jonathan Cameron wrote:
>On Fri, 9 Jan 2026 18:14:36 +0530
>Neeraj Kumar <s.neeraj@samsung.com> wrote:
>
>> create_pmem_region() creates CXL region based on region information
>> parsed from the Label Storage Area (LSA). This routine requires cxl
>> endpoint decoder and root decoder. Add cxl_find_root_decoder_by_port()
>> and cxl_find_free_ep_decoder() to find the root decoder and a free
>> endpoint decoder respectively.
>>
>> Signed-off-by: Neeraj Kumar <s.neeraj@samsung.com>
>Hi Neeraj,
>
>Just a few minor things.
>
>Jonathan
>
>> diff --git a/drivers/cxl/core/pmem_region.c b/drivers/cxl/core/pmem_region.c
>> index 53d3d81e9676..4a8cf8322cf0 100644
>> --- a/drivers/cxl/core/pmem_region.c
>> +++ b/drivers/cxl/core/pmem_region.c
>> @@ -287,3 +287,139 @@ int devm_cxl_add_pmem_region(struct cxl_region *cxlr)
>> cxlr->cxl_nvb = NULL;
>> return rc;
>> }
>> +
>> +static int match_root_decoder_by_dport(struct device *dev, const void *data)
>> +{
>> + const struct cxl_port *ep_port = data;
>> + struct cxl_root_decoder *cxlrd;
>> + struct cxl_port *root_port;
>> + struct cxl_decoder *cxld;
>> + struct cxl_dport *dport;
>> + bool dport_matched = false;
>> +
>> + if (!is_root_decoder(dev))
>> + return 0;
>> +
>> + cxld = to_cxl_decoder(dev);
>> + if (!(cxld->flags & CXL_DECODER_F_PMEM))
>> + return 0;
>> +
>> + cxlrd = to_cxl_root_decoder(dev);
>> +
>> + root_port = cxlrd_to_port(cxlrd);
>> + dport = cxl_find_dport_by_dev(root_port, ep_port->host_bridge);
>> + if (!dport)
>> + return 0;
>> +
>There is a fairly standard way to check if a loop matched without
>needing a boolean. Just check if the exit condition was reached.
>
>drop declaration of i out of here.
>> + for (int i = 0; i < cxlrd->cxlsd.nr_targets; i++) {
>> + if (dport == cxlrd->cxlsd.target[i]) {
>> + dport_matched = true;
>No need for this.
>> + break;
>> + }
>> + }
>> +
>> + if (!dport_matched)
> if (i == cxlrd->cxlsd.nr_targets)
> return 0;
Thanks for your suggestion. I have fixed it accordingly in V6.
>
>> + return 0;
>> +
>> + return is_root_decoder(dev);
>> +}
>> +
>> +/**
>> + * cxl_find_root_decoder_by_port() - find a cxl root decoder on cxl bus
>> + * @port: any descendant port in CXL port topology
>> + * @cxled: endpoint decoder
>> + *
>> + * Caller of this function must call put_device() when done as a device ref
>> + * is taken via device_find_child()
>> + */
>> +static struct cxl_root_decoder *
>> +cxl_find_root_decoder_by_port(struct cxl_port *port,
>> + struct cxl_endpoint_decoder *cxled)
>> +{
>> + struct cxl_root *cxl_root __free(put_cxl_root) = find_cxl_root(port);
>> + struct cxl_port *ep_port = cxled_to_port(cxled);
>> + struct device *dev;
>> +
>> + if (!cxl_root)
>> + return NULL;
>> +
>> + dev = device_find_child(&cxl_root->port.dev, ep_port,
>> + match_root_decoder_by_dport);
>> + if (!dev)
>> + return NULL;
>> +
>> + return to_cxl_root_decoder(dev);
>> +}
>
>> +void create_pmem_region(struct nvdimm *nvdimm)
>> +{
>> + struct cxl_region *cxlr;
>> + struct cxl_memdev *cxlmd;
>> + struct cxl_nvdimm *cxl_nvd;
>> + struct cxl_endpoint_decoder *cxled;
>> + struct cxl_pmem_region_params *params;
>
>CXL tends to be reverse xmas tree and good to stick to local style.
Changed them in reverse xmas tree style.
Regards,
Neeraj
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end of thread, other threads:[~2026-01-23 11:35 UTC | newest]
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[not found] <CGME20260109124454epcas5p4513168fdb4253ef1c5ac1656985417fd@epcas5p4.samsung.com>
2026-01-09 12:44 ` [PATCH V5 00/17] Add CXL LSA 2.1 format support in nvdimm and cxl pmem Neeraj Kumar
2026-01-09 12:44 ` [PATCH V5 01/17] nvdimm/label: Introduce NDD_REGION_LABELING flag to set region label Neeraj Kumar
2026-01-14 21:22 ` Ira Weiny
2026-01-09 12:44 ` [PATCH V5 02/17] nvdimm/label: CXL labels skip the need for 'interleave-set cookie' Neeraj Kumar
2026-01-09 12:44 ` [PATCH V5 03/17] nvdimm/label: Add namespace/region label support as per LSA 2.1 Neeraj Kumar
2026-01-15 17:45 ` Jonathan Cameron
2026-01-23 10:57 ` Neeraj Kumar
2026-01-21 0:35 ` Ira Weiny
2026-01-09 12:44 ` [PATCH V5 04/17] nvdimm/label: Include region label in slot validation Neeraj Kumar
2026-01-14 21:20 ` Ira Weiny
2026-01-23 11:02 ` Neeraj Kumar
2026-01-15 17:55 ` Jonathan Cameron
2026-01-21 0:38 ` Ira Weiny
2026-01-09 12:44 ` [PATCH V5 05/17] nvdimm/label: Skip region label during ns label DPA reservation Neeraj Kumar
2026-01-15 17:56 ` Jonathan Cameron
2026-01-21 0:41 ` Ira Weiny
2026-01-23 11:05 ` Neeraj Kumar
2026-01-09 12:44 ` [PATCH V5 06/17] nvdimm/label: Preserve region label during namespace creation Neeraj Kumar
2026-01-15 17:59 ` Jonathan Cameron
2026-01-21 0:43 ` Ira Weiny
2026-01-09 12:44 ` [PATCH V5 07/17] nvdimm/label: Add region label delete support Neeraj Kumar
2026-01-21 0:44 ` Ira Weiny
2026-01-09 12:44 ` [PATCH V5 08/17] nvdimm/label: Preserve cxl region information from region label Neeraj Kumar
2026-01-15 18:03 ` Jonathan Cameron
2026-01-23 11:08 ` Neeraj Kumar
2026-01-21 0:45 ` Ira Weiny
2026-01-09 12:44 ` [PATCH V5 09/17] nvdimm/label: Export routine to fetch region information Neeraj Kumar
2026-01-15 18:03 ` Jonathan Cameron
2026-01-21 0:46 ` Ira Weiny
2026-01-23 11:11 ` Neeraj Kumar
2026-01-23 11:20 ` Neeraj Kumar
2026-01-09 12:44 ` [PATCH V5 10/17] cxl/mem: Refactor cxl pmem region auto-assembling Neeraj Kumar
2026-01-15 18:08 ` Jonathan Cameron
2026-01-23 11:14 ` Neeraj Kumar
2026-01-09 12:44 ` [PATCH V5 11/17] cxl/region: Add devm_cxl_pmem_add_region() for pmem region creation Neeraj Kumar
2026-01-15 18:17 ` Jonathan Cameron
2026-01-23 11:17 ` Neeraj Kumar
2026-01-09 12:44 ` [PATCH V5 12/17] cxl/pmem: Preserve region information into nd_set Neeraj Kumar
2026-01-15 18:18 ` Jonathan Cameron
2026-01-09 12:44 ` [PATCH V5 13/17] cxl/pmem_region: Prep patch to accommodate pmem_region attributes Neeraj Kumar
2026-01-09 12:44 ` [PATCH V5 14/17] cxl/pmem_region: Introduce CONFIG_CXL_PMEM_REGION for core/pmem_region.c Neeraj Kumar
2026-01-15 18:19 ` Jonathan Cameron
2026-01-09 12:44 ` [PATCH V5 15/17] cxl/pmem_region: Add sysfs attribute cxl region label updation/deletion Neeraj Kumar
2026-01-14 17:00 ` Dave Jiang
2026-01-23 11:22 ` Neeraj Kumar
2026-01-15 18:21 ` Jonathan Cameron
2026-01-23 11:25 ` Neeraj Kumar
2026-01-09 12:44 ` [PATCH V5 16/17] cxl/pmem_region: Create pmem region using information parsed from LSA Neeraj Kumar
2026-01-15 18:28 ` Jonathan Cameron
2026-01-23 11:28 ` Neeraj Kumar
2026-01-09 12:44 ` [PATCH V5 17/17] cxl/pmem: Add CXL LSA 2.1 support in cxl pmem Neeraj Kumar
2026-01-15 18:29 ` Jonathan Cameron
2026-01-21 15:37 ` [PATCH V5 00/17] Add CXL LSA 2.1 format support in nvdimm and " Dave Jiang
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