Merge: [RHEL9.5] DMA Engine Updates

MR: https://gitlab.com/redhat/centos-stream/src/kernel/centos-stream-9/-/merge_requests/3948

# Merge Request Required Information

JIRA: https://issues.redhat.com/browse/RHEL-28792  
JIRA: https://issues.redhat.com/browse/RHEL-28869  
Upstream Status: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git  
CVE: CVE-2023-52492  
Tested: dsa_user_test_runner, iaa_user_test_runner for idxd driver. dmatest for idxd legacy support, ioat, ptdma  

## Summary of Changes

This rebases the supported dma engine subsystem drivers to 6.9-rc1. It contains various fixes, and updating some drivers to use
new platform remove callback.

It also completes the driver core change to constify the bus_type struct in the device and device_driver structs, which required a commit to modify rhel-only code in the vfio driver.

## Approved Development Ticket
All submissions to CentOS Stream must reference an approved ticket in [Red Hat Jira](https://issues.redhat.com/). Please follow the CentOS Stream [contribution documentation](https://docs.centos.org/en-US/stream-contrib/quickstart/) for how to file this ticket and have it approved.

Signed-off-by: Jerry Snitselaar <jsnitsel@redhat.com>

Approved-by: Steve Best <sbest@redhat.com>
Approved-by: John W. Linville <linville@redhat.com>
Approved-by: Mark Langsdorf <mlangsdo@redhat.com>
Approved-by: Andrew Halaney <ahalaney@redhat.com>
Approved-by: Jocelyn Falempe <jfalempe@redhat.com>
Approved-by: Myron Stowe <mstowe@redhat.com>
Approved-by: CKI KWF Bot <cki-ci-bot+kwf-gitlab-com@redhat.com>

Merged-by: Lucas Zampieri <lzampier@redhat.com>

Author: zampierilucas

drivers/base/bus.c

@@ -1030,7 +1030,7 @@ static void device_insertion_sort_klist(struct device *a, struct list_head *list
 	list_move_tail(&a->p->knode_bus.n_node, list);
 }
 
-void bus_sort_breadthfirst(struct bus_type *bus,
+void bus_sort_breadthfirst(const struct bus_type *bus,
 			   int (*compare)(const struct device *a,
 					  const struct device *b))
 {
@@ -1194,7 +1194,7 @@ static void system_root_device_release(struct device *dev)
 	kfree(dev);
 }
 
-static int subsys_register(struct bus_type *subsys,
+static int subsys_register(const struct bus_type *subsys,
 			   const struct attribute_group **groups,
 			   struct kobject *parent_of_root)
 {
@@ -1264,7 +1264,7 @@ static int subsys_register(struct bus_type *subsys,
  * directory itself and not some create fake root-device placed in
  * /sys/devices/system/<name>.
  */
-int subsys_system_register(struct bus_type *subsys,
+int subsys_system_register(const struct bus_type *subsys,
 			   const struct attribute_group **groups)
 {
 	return subsys_register(subsys, groups, &system_kset->kobj);
@@ -1282,7 +1282,7 @@ EXPORT_SYMBOL_GPL(subsys_system_register);
  * There's no restriction on device naming.  This is for kernel software
  * constructs which need sysfs interface.
  */
-int subsys_virtual_register(struct bus_type *subsys,
+int subsys_virtual_register(const struct bus_type *subsys,
 			    const struct attribute_group **groups)
 {
 	struct kobject *virtual_dir;

drivers/base/power/clock_ops.c

@@ -793,7 +793,7 @@ static int pm_clk_notify(struct notifier_block *nb,
  * the remaining members of @clknb should be populated prior to calling this
  * routine.
  */
-void pm_clk_add_notifier(struct bus_type *bus,
+void pm_clk_add_notifier(const struct bus_type *bus,
 				 struct pm_clk_notifier_block *clknb)
 {
 	if (!bus || !clknb)

drivers/dma/dmaengine.c

@@ -1103,6 +1103,9 @@ EXPORT_SYMBOL_GPL(dma_async_device_channel_register);
 static void __dma_async_device_channel_unregister(struct dma_device *device,
 						  struct dma_chan *chan)
 {
+	if (chan->local == NULL)
+		return;
+
 	WARN_ONCE(!device->device_release && chan->client_count,
 		  "%s called while %d clients hold a reference\n",
 		  __func__, chan->client_count);

drivers/dma/dmatest.c

@@ -21,6 +21,10 @@
 #include <linux/slab.h>
 #include <linux/wait.h>
 
+static bool nobounce;
+module_param(nobounce, bool, 0644);
+MODULE_PARM_DESC(nobounce, "Prevent using swiotlb buffer (default: use swiotlb buffer)");
+
 static unsigned int test_buf_size = 16384;
 module_param(test_buf_size, uint, 0644);
 MODULE_PARM_DESC(test_buf_size, "Size of the memcpy test buffer");
@@ -90,6 +94,7 @@ MODULE_PARM_DESC(polled, "Use polling for completion instead of interrupts");
 
 /**
  * struct dmatest_params - test parameters.
+ * @nobounce:		prevent using swiotlb buffer
  * @buf_size:		size of the memcpy test buffer
  * @channel:		bus ID of the channel to test
  * @device:		bus ID of the DMA Engine to test
@@ -106,6 +111,7 @@ MODULE_PARM_DESC(polled, "Use polling for completion instead of interrupts");
  * @polled:		use polling for completion instead of interrupts
  */
 struct dmatest_params {
+	bool		nobounce;
 	unsigned int	buf_size;
 	char		channel[20];
 	char		device[32];
@@ -215,6 +221,7 @@ struct dmatest_done {
 struct dmatest_data {
 	u8		**raw;
 	u8		**aligned;
+	gfp_t		gfp_flags;
 	unsigned int	cnt;
 	unsigned int	off;
 };
@@ -533,7 +540,7 @@ static int dmatest_alloc_test_data(struct dmatest_data *d,
 		goto err;
 
 	for (i = 0; i < d->cnt; i++) {
-		d->raw[i] = kmalloc(buf_size + align, GFP_KERNEL);
+		d->raw[i] = kmalloc(buf_size + align, d->gfp_flags);
 		if (!d->raw[i])
 			goto err;
 
@@ -655,6 +662,13 @@ static int dmatest_func(void *data)
 		goto err_free_coefs;
 	}
 
+	src->gfp_flags = GFP_KERNEL;
+	dst->gfp_flags = GFP_KERNEL;
+	if (params->nobounce) {
+		src->gfp_flags = GFP_DMA;
+		dst->gfp_flags = GFP_DMA;
+	}
+
 	if (dmatest_alloc_test_data(src, buf_size, align) < 0)
 		goto err_free_coefs;
 
@@ -1093,6 +1107,7 @@ static void add_threaded_test(struct dmatest_info *info)
 	struct dmatest_params *params = &info->params;
 
 	/* Copy test parameters */
+	params->nobounce = nobounce;
 	params->buf_size = test_buf_size;
 	strscpy(params->channel, strim(test_channel), sizeof(params->channel));
 	strscpy(params->device, strim(test_device), sizeof(params->device));

drivers/dma/dw/platform.c

@@ -93,7 +93,7 @@ static int dw_probe(struct platform_device *pdev)
 	return err;
 }
 
-static int dw_remove(struct platform_device *pdev)
+static void dw_remove(struct platform_device *pdev)
 {
 	struct dw_dma_chip_pdata *data = platform_get_drvdata(pdev);
 	struct dw_dma_chip *chip = data->chip;
@@ -109,8 +109,6 @@ static int dw_remove(struct platform_device *pdev)
 
 	pm_runtime_disable(&pdev->dev);
 	clk_disable_unprepare(chip->clk);
-
-	return 0;
 }
 
 static void dw_shutdown(struct platform_device *pdev)
@@ -192,7 +190,7 @@ static const struct dev_pm_ops dw_dev_pm_ops = {
 
 static struct platform_driver dw_driver = {
 	.probe		= dw_probe,
-	.remove		= dw_remove,
+	.remove_new	= dw_remove,
 	.shutdown       = dw_shutdown,
 	.driver = {
 		.name	= DRV_NAME,

drivers/dma/idma64.c

@@ -660,13 +660,11 @@ static int idma64_platform_probe(struct platform_device *pdev)
 	return 0;
 }
 
-static int idma64_platform_remove(struct platform_device *pdev)
+static void idma64_platform_remove(struct platform_device *pdev)
 {
 	struct idma64_chip *chip = platform_get_drvdata(pdev);
 
 	idma64_remove(chip);
-
-	return 0;
 }
 
 static int __maybe_unused idma64_pm_suspend(struct device *dev)
@@ -691,7 +689,7 @@ static const struct dev_pm_ops idma64_dev_pm_ops = {
 
 static struct platform_driver idma64_platform_driver = {
 	.probe		= idma64_platform_probe,
-	.remove		= idma64_platform_remove,
+	.remove_new	= idma64_platform_remove,
 	.driver = {
 		.name	= LPSS_IDMA64_DRIVER_NAME,
 		.pm	= &idma64_dev_pm_ops,

drivers/dma/idxd/Makefile

@@ -1,12 +1,12 @@
 ccflags-y += -DDEFAULT_SYMBOL_NAMESPACE=IDXD
 
+obj-$(CONFIG_INTEL_IDXD_BUS) += idxd_bus.o
+idxd_bus-y := bus.o
+
 obj-$(CONFIG_INTEL_IDXD) += idxd.o
 idxd-y := init.o irq.o device.o sysfs.o submit.o dma.o cdev.o debugfs.o defaults.o
 
 idxd-$(CONFIG_INTEL_IDXD_PERFMON) += perfmon.o
 
-obj-$(CONFIG_INTEL_IDXD_BUS) += idxd_bus.o
-idxd_bus-y := bus.o
-
 obj-$(CONFIG_INTEL_IDXD_COMPAT) += idxd_compat.o
 idxd_compat-y := compat.o

drivers/dma/idxd/bus.c

@@ -72,7 +72,7 @@ static int idxd_bus_uevent(const struct device *dev, struct kobj_uevent_env *env
 	return add_uevent_var(env, "MODALIAS=" IDXD_DEVICES_MODALIAS_FMT, 0);
 }
 
-struct bus_type dsa_bus_type = {
+const struct bus_type dsa_bus_type = {
 	.name = "dsa",
 	.match = idxd_config_bus_match,
 	.probe = idxd_config_bus_probe,

drivers/dma/idxd/cdev.c

@@ -152,7 +152,7 @@ static void idxd_file_dev_release(struct device *dev)
 	mutex_unlock(&wq->wq_lock);
 }
 
-static struct device_type idxd_cdev_file_type = {
+static const struct device_type idxd_cdev_file_type = {
 	.name = "idxd_file",
 	.release = idxd_file_dev_release,
 	.groups = cdev_file_attribute_groups,
@@ -165,11 +165,11 @@ static void idxd_cdev_dev_release(struct device *dev)
 	struct idxd_wq *wq = idxd_cdev->wq;
 
 	cdev_ctx = &ictx[wq->idxd->data->type];
-	ida_simple_remove(&cdev_ctx->minor_ida, idxd_cdev->minor);
+	ida_free(&cdev_ctx->minor_ida, idxd_cdev->minor);
 	kfree(idxd_cdev);
 }
 
-static struct device_type idxd_cdev_device_type = {
+static const struct device_type idxd_cdev_device_type = {
 	.name = "idxd_cdev",
 	.release = idxd_cdev_dev_release,
 };
@@ -463,7 +463,7 @@ int idxd_wq_add_cdev(struct idxd_wq *wq)
 	cdev = &idxd_cdev->cdev;
 	dev = cdev_dev(idxd_cdev);
 	cdev_ctx = &ictx[wq->idxd->data->type];
-	minor = ida_simple_get(&cdev_ctx->minor_ida, 0, MINORMASK, GFP_KERNEL);
+	minor = ida_alloc_max(&cdev_ctx->minor_ida, MINORMASK, GFP_KERNEL);
 	if (minor < 0) {
 		kfree(idxd_cdev);
 		return minor;

drivers/dma/idxd/idxd.h

@@ -282,7 +282,7 @@ typedef int (*load_device_defaults_fn_t) (struct idxd_device *idxd);
 struct idxd_driver_data {
 	const char *name_prefix;
 	enum idxd_type type;
-	struct device_type *dev_type;
+	const struct device_type *dev_type;
 	int compl_size;
 	int align;
 	int evl_cr_off;
@@ -515,15 +515,15 @@ static inline void idxd_set_user_intr(struct idxd_device *idxd, bool enable)
 	iowrite32(reg.bits, idxd->reg_base + IDXD_GENCFG_OFFSET);
 }
 
-extern struct bus_type dsa_bus_type;
+extern const struct bus_type dsa_bus_type;
 
 extern bool support_enqcmd;
 extern struct ida idxd_ida;
-extern struct device_type dsa_device_type;
-extern struct device_type iax_device_type;
-extern struct device_type idxd_wq_device_type;
-extern struct device_type idxd_engine_device_type;
-extern struct device_type idxd_group_device_type;
+extern const struct device_type dsa_device_type;
+extern const struct device_type iax_device_type;
+extern const struct device_type idxd_wq_device_type;
+extern const struct device_type idxd_engine_device_type;
+extern const struct device_type idxd_group_device_type;
 
 static inline bool is_dsa_dev(struct idxd_dev *idxd_dev)
 {