[PATCH v2 07/15] cxl: support type2 memdev creation

alejandro.lucero-palau
2024-07-15T17:28:57Z

From: Alejandro Lucero <alucerop@amd.com>

Add memdev creation from sfc driver.

Current cxl core is relying on a CXL_DEVTYPE_CLASSMEM type device when
creating a memdev leading to problems when obtaining cxl_memdev_state
references from a CXL_DEVTYPE_DEVMEM type. This last device type is
managed by a specific vendor driver and does not need same sysfs files
since not userspace intervention is expected. This patch checks for the
right device type in those functions using cxl_memdev_state.

Signed-off-by: Alejandro Lucero <alucerop@amd.com>
---
drivers/cxl/core/cdat.c | 3 +++
drivers/cxl/core/memdev.c | 9 +++++++++
drivers/cxl/mem.c | 17 +++++++++++------
drivers/net/ethernet/sfc/efx_cxl.c | 10 ++++++++--
include/linux/cxl_accel_mem.h | 3 +++
5 files changed, 34 insertions(+), 8 deletions(-)

diff --git a/drivers/cxl/core/cdat.c b/drivers/cxl/core/cdat.c
index bb83867d9fec..0d4679c137d4 100644
--- a/drivers/cxl/core/cdat.c
+++ b/drivers/cxl/core/cdat.c
@@ -558,6 +558,9 @@ void cxl_region_perf_data_calculate(struct cxl_region *cxlr,
};
struct cxl_dpa_perf *perf;

+ if (!mds)
+ return;
+
switch (cxlr->mode) {
case CXL_DECODER_RAM:
perf = &mds->ram_perf;
diff --git a/drivers/cxl/core/memdev.c b/drivers/cxl/core/memdev.c
index 58a51e7fd37f..b902948b121f 100644
--- a/drivers/cxl/core/memdev.c
+++ b/drivers/cxl/core/memdev.c
@@ -468,6 +468,9 @@ static umode_t cxl_ram_visible(struct kobject *kobj, struct attribute *a, int n)
struct cxl_memdev *cxlmd = to_cxl_memdev(dev);
struct cxl_memdev_state *mds = to_cxl_memdev_state(cxlmd->cxlds);

+ if (!mds)
+ return 0;
+
if (a == &dev_attr_ram_qos_class.attr)
if (mds->ram_perf.qos_class == CXL_QOS_CLASS_INVALID)
return 0;
@@ -487,6 +490,9 @@ static umode_t cxl_pmem_visible(struct kobject *kobj, struct attribute *a, int n
struct cxl_memdev *cxlmd = to_cxl_memdev(dev);
struct cxl_memdev_state *mds = to_cxl_memdev_state(cxlmd->cxlds);

+ if (!mds)
+ return 0;
+
if (a == &dev_attr_pmem_qos_class.attr)
if (mds->pmem_perf.qos_class == CXL_QOS_CLASS_INVALID)
return 0;
@@ -507,6 +513,9 @@ static umode_t cxl_memdev_security_visible(struct kobject *kobj,
struct cxl_memdev *cxlmd = to_cxl_memdev(dev);
struct cxl_memdev_state *mds = to_cxl_memdev_state(cxlmd->cxlds);

+ if (!mds)
+ return 0;
+
if (a == &dev_attr_security_sanitize.attr &&
!test_bit(CXL_SEC_ENABLED_SANITIZE, mds->security.enabled_cmds))
return 0;
diff --git a/drivers/cxl/mem.c b/drivers/cxl/mem.c
index 2f1b49bfe162..f76af75a87b7 100644
--- a/drivers/cxl/mem.c
+++ b/drivers/cxl/mem.c
@@ -131,12 +131,14 @@ static int cxl_mem_probe(struct device *dev)
dentry = cxl_debugfs_create_dir(dev_name(dev));
debugfs_create_devm_seqfile(dev, "dpamem", dentry, cxl_mem_dpa_show);

- if (test_bit(CXL_POISON_ENABLED_INJECT, mds->poison.enabled_cmds))
- debugfs_create_file("inject_poison", 0200, dentry, cxlmd,
- &cxl_poison_inject_fops);
- if (test_bit(CXL_POISON_ENABLED_CLEAR, mds->poison.enabled_cmds))
- debugfs_create_file("clear_poison", 0200, dentry, cxlmd,
- &cxl_poison_clear_fops);
+ if (mds) {
+ if (test_bit(CXL_POISON_ENABLED_INJECT, mds->poison.enabled_cmds))
+ debugfs_create_file("inject_poison", 0200, dentry, cxlmd,
+ &cxl_poison_inject_fops);
+ if (test_bit(CXL_POISON_ENABLED_CLEAR, mds->poison.enabled_cmds))
+ debugfs_create_file("clear_poison", 0200, dentry, cxlmd,
+ &cxl_poison_clear_fops);
+ }

rc = devm_add_action_or_reset(dev, remove_debugfs, dentry);
if (rc)
@@ -222,6 +224,9 @@ static umode_t cxl_mem_visible(struct kobject *kobj, struct attribute *a, int n)
struct cxl_memdev *cxlmd = to_cxl_memdev(dev);
struct cxl_memdev_state *mds = to_cxl_memdev_state(cxlmd->cxlds);

+ if (!mds)
+ return 0;
+
if (a == &dev_attr_trigger_poison_list.attr)
if (!test_bit(CXL_POISON_ENABLED_LIST,
mds->poison.enabled_cmds))
diff --git a/drivers/net/ethernet/sfc/efx_cxl.c b/drivers/net/ethernet/sfc/efx_cxl.c
index a84fe7992c53..0abe66490ef5 100644
--- a/drivers/net/ethernet/sfc/efx_cxl.c
+++ b/drivers/net/ethernet/sfc/efx_cxl.c
@@ -57,10 +57,16 @@ void efx_cxl_init(struct efx_nic *efx)
if (cxl_accel_request_resource(cxl->cxlds, true))
pci_info(pci_dev, "CXL accel resource request failed");

- if (!cxl_await_media_ready(cxl->cxlds))
+ if (!cxl_await_media_ready(cxl->cxlds)) {
cxl_accel_set_media_ready(cxl->cxlds);
- else
+ } else {
pci_info(pci_dev, "CXL accel media not active");
+ return;
+ }
+
+ cxl->cxlmd = devm_cxl_add_memdev(&pci_dev->dev, cxl->cxlds);
+ if (IS_ERR(cxl->cxlmd))
+ pci_info(pci_dev, "CXL accel memdev creation failed");
}

diff --git a/include/linux/cxl_accel_mem.h b/include/linux/cxl_accel_mem.h
index b883c438a132..442ed9862292 100644
--- a/include/linux/cxl_accel_mem.h
+++ b/include/linux/cxl_accel_mem.h
@@ -26,4 +26,7 @@ int cxl_pci_accel_setup_regs(struct pci_dev *pdev, struct cxl_dev_state *cxlds);
int cxl_accel_request_resource(struct cxl_dev_state *cxlds, bool is_ram);
void cxl_accel_set_media_ready(struct cxl_dev_state *cxlds);
int cxl_await_media_ready(struct cxl_dev_state *cxlds);
+
+struct cxl_memdev *devm_cxl_add_memdev(struct device *host,
+ struct cxl_dev_state *cxlds);
#endif
--
2.17.1