[PATCH v3 1/8] platform/x86/intel/ifs: Reorganize driver data

[Jithu Joseph]

The struct holding device driver data contained both read only(ro)
and read write(rw) fields.

Separating ro fields from rw fields was recommended as
a preferable design pattern during review[1].

Group the rw fields into a separate struct whose memory is allocated
during driver_init(). Associate it to the miscdevice being registered
by keeping it in the same container struct as the miscdevice.

Also in prepration to supporting additional tests, move ifs_pkg_auth
to a global as it is only applicable for the first test type.

Link: https://lore.kernel.org/lkml/Y+9H9otxLYPqMkUh@xxxxxxxxx/ [1]

Signed-off-by: Jithu Joseph <jithu.joseph@xxxxxxxxx>
Reviewed-by: Tony Luck <tony.luck@xxxxxxxxx>
---
 drivers/platform/x86/intel/ifs/ifs.h  | 19 +++++++++-------
 drivers/platform/x86/intel/ifs/core.c | 31 ++++++++++++++++++---------
 drivers/platform/x86/intel/ifs/load.c |  8 +++----
 3 files changed, 36 insertions(+), 22 deletions(-)

diff --git a/drivers/platform/x86/intel/ifs/ifs.h b/drivers/platform/x86/intel/ifs/ifs.h
index 046e39304fd5..e07463c794d4 100644
--- a/drivers/platform/x86/intel/ifs/ifs.h
+++ b/drivers/platform/x86/intel/ifs/ifs.h
@@ -197,22 +197,23 @@ union ifs_status {
 #define IFS_SW_TIMEOUT				0xFD
 #define IFS_SW_PARTIAL_COMPLETION		0xFE
 
+struct ifs_const_data {
+	int	integrity_cap_bit;
+	int	test_num;
+};
+
 /**
  * struct ifs_data - attributes related to intel IFS driver
- * @integrity_cap_bit: MSR_INTEGRITY_CAPS bit enumerating this test
  * @loaded_version: stores the currently loaded ifs image version.
- * @pkg_auth: array of bool storing per package auth status
  * @loaded: If a valid test binary has been loaded into the memory
  * @loading_error: Error occurred on another CPU while loading image
  * @valid_chunks: number of chunks which could be validated.
  * @status: it holds simple status pass/fail/untested
  * @scan_details: opaque scan status code from h/w
  * @cur_batch: number indicating the currently loaded test file
- * @test_num: number indicating the test type
+ * @ro_info: ptr to struct holding fixed details
  */
 struct ifs_data {
-	int	integrity_cap_bit;
-	bool	*pkg_auth;
 	int	loaded_version;
 	bool	loaded;
 	bool	loading_error;
@@ -220,7 +221,7 @@ struct ifs_data {
 	int	status;
 	u64	scan_details;
 	u32	cur_batch;
-	int	test_num;
+	struct ifs_const_data *ro_info;
 };
 
 struct ifs_work {
@@ -229,7 +230,8 @@ struct ifs_work {
 };
 
 struct ifs_device {
-	struct ifs_data data;
+	struct ifs_const_data ro_data;
+	struct ifs_data *rw_data;
 	struct miscdevice misc;
 };
 
@@ -238,9 +240,10 @@ static inline struct ifs_data *ifs_get_data(struct device *dev)
 	struct miscdevice *m = dev_get_drvdata(dev);
 	struct ifs_device *d = container_of(m, struct ifs_device, misc);
 
-	return &d->data;
+	return d->rw_data;
 }
 
+extern bool *ifs_pkg_auth;
 int ifs_load_firmware(struct device *dev);
 int do_core_test(int cpu, struct device *dev);
 const struct attribute_group **ifs_get_groups(void);
diff --git a/drivers/platform/x86/intel/ifs/core.c b/drivers/platform/x86/intel/ifs/core.c
index 206a617c2e02..b518b661daf0 100644
--- a/drivers/platform/x86/intel/ifs/core.c
+++ b/drivers/platform/x86/intel/ifs/core.c
@@ -20,8 +20,10 @@ static const struct x86_cpu_id ifs_cpu_ids[] __initconst = {
 };
 MODULE_DEVICE_TABLE(x86cpu, ifs_cpu_ids);
 
+bool *ifs_pkg_auth;
+
 static struct ifs_device ifs_device = {
-	.data = {
+	.ro_data = {
 		.integrity_cap_bit = MSR_INTEGRITY_CAPS_PERIODIC_BIST_BIT,
 		.test_num = 0,
 	},
@@ -35,8 +37,8 @@ static struct ifs_device ifs_device = {
 static int __init ifs_init(void)
 {
 	const struct x86_cpu_id *m;
+	struct ifs_data *ifsd;
 	u64 msrval;
-	int ret;
 
 	m = x86_match_cpu(ifs_cpu_ids);
 	if (!m)
@@ -53,26 +55,35 @@ static int __init ifs_init(void)
 
 	ifs_device.misc.groups = ifs_get_groups();
 
-	if (!(msrval & BIT(ifs_device.data.integrity_cap_bit)))
+	if (!(msrval & BIT(ifs_device.ro_data.integrity_cap_bit)))
 		return -ENODEV;
 
-	ifs_device.data.pkg_auth = kmalloc_array(topology_max_packages(), sizeof(bool), GFP_KERNEL);
-	if (!ifs_device.data.pkg_auth)
+	ifs_pkg_auth = kmalloc_array(topology_max_packages(), sizeof(bool), GFP_KERNEL);
+	if (!ifs_pkg_auth)
+		return -ENOMEM;
+
+	ifsd = kzalloc(sizeof(*ifsd), GFP_KERNEL);
+	if (!ifsd)
 		return -ENOMEM;
 
-	ret = misc_register(&ifs_device.misc);
-	if (ret) {
-		kfree(ifs_device.data.pkg_auth);
-		return ret;
+	ifsd->ro_info = &ifs_device.ro_data;
+	ifs_device.rw_data = ifsd;
+
+	if (misc_register(&ifs_device.misc)) {
+		kfree(ifsd);
+		kfree(ifs_pkg_auth);
+		return -ENODEV;
 	}
 
 	return 0;
+
 }
 
 static void __exit ifs_exit(void)
 {
 	misc_deregister(&ifs_device.misc);
-	kfree(ifs_device.data.pkg_auth);
+	kfree(ifs_device.rw_data);
+	kfree(ifs_pkg_auth);
 }
 
 module_init(ifs_init);
diff --git a/drivers/platform/x86/intel/ifs/load.c b/drivers/platform/x86/intel/ifs/load.c
index c5c24e6fdc43..cdec3316c08d 100644
--- a/drivers/platform/x86/intel/ifs/load.c
+++ b/drivers/platform/x86/intel/ifs/load.c
@@ -192,7 +192,7 @@ static int scan_chunks_sanity_check(struct device *dev)
 	struct ifs_work local_work;
 	int curr_pkg, cpu, ret;
 
-	memset(ifsd->pkg_auth, 0, (topology_max_packages() * sizeof(bool)));
+	memset(ifs_pkg_auth, 0, (topology_max_packages() * sizeof(bool)));
 	ret = validate_ifs_metadata(dev);
 	if (ret)
 		return ret;
@@ -204,7 +204,7 @@ static int scan_chunks_sanity_check(struct device *dev)
 	cpus_read_lock();
 	for_each_online_cpu(cpu) {
 		curr_pkg = topology_physical_package_id(cpu);
-		if (ifsd->pkg_auth[curr_pkg])
+		if (ifs_pkg_auth[curr_pkg])
 			continue;
 		reinit_completion(&ifs_done);
 		local_work.dev = dev;
@@ -215,7 +215,7 @@ static int scan_chunks_sanity_check(struct device *dev)
 			ret = -EIO;
 			goto out;
 		}
-		ifsd->pkg_auth[curr_pkg] = 1;
+		ifs_pkg_auth[curr_pkg] = 1;
 	}
 	ret = 0;
 out:
@@ -263,7 +263,7 @@ int ifs_load_firmware(struct device *dev)
 	int ret = -EINVAL;
 
 	snprintf(scan_path, sizeof(scan_path), "intel/ifs_%d/%02x-%02x-%02x-%02x.scan",
-		 ifsd->test_num, boot_cpu_data.x86, boot_cpu_data.x86_model,
+		 ifsd->ro_info->test_num, boot_cpu_data.x86, boot_cpu_data.x86_model,
 		 boot_cpu_data.x86_stepping, ifsd->cur_batch);
 
 	ret = request_firmware_direct(&fw, scan_path, dev);
-- 
2.25.1