cxl: sysfs support for guests

Filter out a few adapter parameters which don't make sense in a guest.
Document the changes.

Co-authored-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
Signed-off-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
Signed-off-by: Christophe Lombard <clombard@linux.vnet.ibm.com>
Reviewed-by: Manoj Kumar <manoj@linux.vnet.ibm.com>
Acked-by: Ian Munsie <imunsie@au1.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

1 files changed, 69 insertions, 20 deletions

diff --git a/drivers/misc/cxl/sysfs.c b/drivers/misc/cxl/sysfs.c
index 1a1409cb1652..907c99b9f5af 100644
--- a/drivers/misc/cxl/sysfs.c
+++ b/drivers/misc/cxl/sysfs.c
@@ -253,8 +253,14 @@ static ssize_t irqs_max_store(struct device *device,
 	if (irqs_max < afu->pp_irqs)
 		return -EINVAL;
 
-	if (irqs_max > afu->adapter->user_irqs)
-		return -EINVAL;
+	if (cpu_has_feature(CPU_FTR_HVMODE)) {
+		if (irqs_max > afu->adapter->user_irqs)
+			return -EINVAL;
+	} else {
+		/* pHyp sets a per-AFU limit */
+		if (irqs_max > afu->guest->max_ints)
+			return -EINVAL;
+	}
 
 	afu->irqs_max = irqs_max;
 	return count;
@@ -406,24 +412,39 @@ static struct device_attribute afu_attrs[] = {
 
 int cxl_sysfs_adapter_add(struct cxl *adapter)
 {
+	struct device_attribute *dev_attr;
 	int i, rc;
 
 	for (i = 0; i < ARRAY_SIZE(adapter_attrs); i++) {
-		if ((rc = device_create_file(&adapter->dev, &adapter_attrs[i])))
-			goto err;
+		dev_attr = &adapter_attrs[i];
+		if (cxl_ops->support_attributes(dev_attr->attr.name,
+						CXL_ADAPTER_ATTRS)) {
+			if ((rc = device_create_file(&adapter->dev, dev_attr)))
+				goto err;
+		}
 	}
 	return 0;
 err:
-	for (i--; i >= 0; i--)
-		device_remove_file(&adapter->dev, &adapter_attrs[i]);
+	for (i--; i >= 0; i--) {
+		dev_attr = &adapter_attrs[i];
+		if (cxl_ops->support_attributes(dev_attr->attr.name,
+						CXL_ADAPTER_ATTRS))
+			device_remove_file(&adapter->dev, dev_attr);
+	}
 	return rc;
 }
+
 void cxl_sysfs_adapter_remove(struct cxl *adapter)
 {
+	struct device_attribute *dev_attr;
 	int i;
 
-	for (i = 0; i < ARRAY_SIZE(adapter_attrs); i++)
-		device_remove_file(&adapter->dev, &adapter_attrs[i]);
+	for (i = 0; i < ARRAY_SIZE(adapter_attrs); i++) {
+		dev_attr = &adapter_attrs[i];
+		if (cxl_ops->support_attributes(dev_attr->attr.name,
+						CXL_ADAPTER_ATTRS))
+			device_remove_file(&adapter->dev, dev_attr);
+	}
 }
 
 struct afu_config_record {
@@ -534,7 +555,7 @@ static struct afu_config_record *cxl_sysfs_afu_new_cr(struct cxl_afu *afu, int c
 	/*
 	 * Export raw AFU PCIe like config record. For now this is read only by
 	 * root - we can expand that later to be readable by non-root and maybe
-	 * even writable provided we have a good use-case. Once we suport
+	 * even writable provided we have a good use-case. Once we support
 	 * exposing AFUs through a virtual PHB they will get that for free from
 	 * Linux' PCI infrastructure, but until then it's not clear that we
 	 * need it for anything since the main use case is just identifying
@@ -572,6 +593,7 @@ err:
 
 void cxl_sysfs_afu_remove(struct cxl_afu *afu)
 {
+	struct device_attribute *dev_attr;
 	struct afu_config_record *cr, *tmp;
 	int i;
 
@@ -579,8 +601,12 @@ void cxl_sysfs_afu_remove(struct cxl_afu *afu)
 	if (afu->eb_len)
 		device_remove_bin_file(&afu->dev, &afu->attr_eb);
 
-	for (i = 0; i < ARRAY_SIZE(afu_attrs); i++)
-		device_remove_file(&afu->dev, &afu_attrs[i]);
+	for (i = 0; i < ARRAY_SIZE(afu_attrs); i++) {
+		dev_attr = &afu_attrs[i];
+		if (cxl_ops->support_attributes(dev_attr->attr.name,
+						CXL_AFU_ATTRS))
+			device_remove_file(&afu->dev, &afu_attrs[i]);
+	}
 
 	list_for_each_entry_safe(cr, tmp, &afu->crs, list) {
 		sysfs_remove_bin_file(&cr->kobj, &cr->config_attr);
@@ -590,14 +616,19 @@ void cxl_sysfs_afu_remove(struct cxl_afu *afu)
 
 int cxl_sysfs_afu_add(struct cxl_afu *afu)
 {
+	struct device_attribute *dev_attr;
 	struct afu_config_record *cr;
 	int i, rc;
 
 	INIT_LIST_HEAD(&afu->crs);
 
 	for (i = 0; i < ARRAY_SIZE(afu_attrs); i++) {
-		if ((rc = device_create_file(&afu->dev, &afu_attrs[i])))
-			goto err;
+		dev_attr = &afu_attrs[i];
+		if (cxl_ops->support_attributes(dev_attr->attr.name,
+						CXL_AFU_ATTRS)) {
+			if ((rc = device_create_file(&afu->dev, &afu_attrs[i])))
+				goto err;
+		}
 	}
 
 	/* conditionally create the add the binary file for error info buffer */
@@ -636,32 +667,50 @@ err:
 	/* reset the eb_len as we havent created the bin attr */
 	afu->eb_len = 0;
 
-	for (i--; i >= 0; i--)
+	for (i--; i >= 0; i--) {
+		dev_attr = &afu_attrs[i];
+		if (cxl_ops->support_attributes(dev_attr->attr.name,
+						CXL_AFU_ATTRS))
 		device_remove_file(&afu->dev, &afu_attrs[i]);
+	}
 	return rc;
 }
 
 int cxl_sysfs_afu_m_add(struct cxl_afu *afu)
 {
+	struct device_attribute *dev_attr;
 	int i, rc;
 
 	for (i = 0; i < ARRAY_SIZE(afu_master_attrs); i++) {
-		if ((rc = device_create_file(afu->chardev_m, &afu_master_attrs[i])))
-			goto err;
+		dev_attr = &afu_master_attrs[i];
+		if (cxl_ops->support_attributes(dev_attr->attr.name,
+						CXL_AFU_MASTER_ATTRS)) {
+			if ((rc = device_create_file(afu->chardev_m, &afu_master_attrs[i])))
+				goto err;
+		}
 	}
 
 	return 0;
 
 err:
-	for (i--; i >= 0; i--)
-		device_remove_file(afu->chardev_m, &afu_master_attrs[i]);
+	for (i--; i >= 0; i--) {
+		dev_attr = &afu_master_attrs[i];
+		if (cxl_ops->support_attributes(dev_attr->attr.name,
+						CXL_AFU_MASTER_ATTRS))
+			device_remove_file(afu->chardev_m, &afu_master_attrs[i]);
+	}
 	return rc;
 }
 
 void cxl_sysfs_afu_m_remove(struct cxl_afu *afu)
 {
+	struct device_attribute *dev_attr;
 	int i;
 
-	for (i = 0; i < ARRAY_SIZE(afu_master_attrs); i++)
-		device_remove_file(afu->chardev_m, &afu_master_attrs[i]);
+	for (i = 0; i < ARRAY_SIZE(afu_master_attrs); i++) {
+		dev_attr = &afu_master_attrs[i];
+		if (cxl_ops->support_attributes(dev_attr->attr.name,
+						CXL_AFU_MASTER_ATTRS))
+			device_remove_file(afu->chardev_m, &afu_master_attrs[i]);
+	}
 }