svm: add svm drv framework for hi1910 and hi1980

ascend inclusion
category: feature
bugzilla: 16554
CVE: NA

--------

add svm driver framework for hi1910 and hi1980,
fistly we add the acpi driver for hi1980;However,
we design the structure for svm;
Signed-off-by: NJiankang Chen <chenjiankang1@huawei.com>
Signed-off-by: NLijun Fang <fanglijun3@huawei.com>
Reviewed-by: NLi Zefan <lizefan@huawei.com>
Reviewed-by: NKefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: NYang Yingliang <yangyingliang@huawei.com>

arch/arm64/include/asm/mmu.h

@@ -29,6 +29,7 @@ typedef struct {
 	atomic64_t	id;
 	unsigned long	pinned;
 	void		*vdso;
+	unsigned long refcount;
 	unsigned long	flags;
 } mm_context_t;
 

arch/arm64/include/asm/mmu_context.h

@@ -244,6 +244,9 @@ switch_mm(struct mm_struct *prev, struct mm_struct *next,
 #define deactivate_mm(tsk,mm)	do { } while (0)
 #define activate_mm(prev,next)	switch_mm(prev, next, current)
 
+unsigned long mm_context_get(struct mm_struct *mm);
+void mm_context_put(struct mm_struct *mm);
+
 void verify_cpu_asid_bits(void);
 void post_ttbr_update_workaround(void);
 

arch/arm64/mm/context.c

@@ -158,6 +158,10 @@ static u64 new_context(struct mm_struct *mm, unsigned int cpu)
 	if (asid != 0) {
 		u64 newasid = generation | (asid & ~ASID_MASK);
 
+		/* That ASID is pinned for us, we're good to go. */
+		if (mm->context.refcount)
+			return newasid;
+
 		/*
 		 * If our current ASID was active during a rollover, we
 		 * can continue to use it and this was just a false alarm.

drivers/char/Kconfig

@@ -552,6 +552,16 @@ config ADI
 	  and SSM (Silicon Secured Memory).  Intended consumers of this
 	  driver include crash and makedumpfile.
 
+config HISI_SVM
+	bool "Hisilicon svm driver"
+	depends on ARM64 && ARM_SMMU_V3 && MMU_NOTIFIER
+	default y
+	help
+	  This driver provides character-level access to Hisilicon
+	  SVM chipset. Typically, you can bind a task to the
+	  svm and share the virtual memory with hisilicon svm device.
+	  When in doubt, say "N".
+
 endmenu
 
 config RANDOM_TRUST_CPU

drivers/char/Makefile

@@ -58,3 +58,4 @@ js-rtc-y = rtc.o
 obj-$(CONFIG_XILLYBUS)		+= xillybus/
 obj-$(CONFIG_POWERNV_OP_PANEL)	+= powernv-op-panel.o
 obj-$(CONFIG_ADI)		+= adi.o
+obj-$(CONFIG_HISI_SVM)		+= svm.o

drivers/char/svm.c

+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2017-2018 Hisilicon Limited.
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+
+#include <asm/esr.h>
+#include <linux/mmu_context.h>
+
+#include <linux/delay.h>
+#include <linux/err.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/iommu.h>
+#include <linux/miscdevice.h>
+#include <linux/mman.h>
+#include <linux/mmu_notifier.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/ptrace.h>
+#include <linux/security.h>
+#include <linux/slab.h>
+#include <linux/uaccess.h>
+#include <linux/sched.h>
+#include <linux/hugetlb.h>
+#include <linux/sched/mm.h>
+#include <linux/msi.h>
+#include <linux/acpi.h>
+
+#define SVM_DEVICE_NAME "svm"
+
+struct core_device {
+	struct device		dev;
+	struct iommu_group      *group;
+	struct iommu_domain     *domain;
+	bool			smmu_bypass;
+};
+
+struct svm_device {
+	unsigned long long	id;
+	struct miscdevice	miscdev;
+	struct device		*dev;
+	phys_addr_t l2buff;
+	unsigned long		l2size;
+};
+
+struct svm_bind_process {
+	pid_t			vpid;
+	u64			ttbr;
+	u64			tcr;
+	int			pasid;
+	u32			flags;
+#define SVM_BIND_PID		(1 << 0)
+};
+
+struct svm_process {
+	struct pid		*pid;
+	struct mm_struct	*mm;
+	unsigned long		asid;
+	struct kref		kref;
+	struct rb_node		rb_node;
+	struct mmu_notifier	notifier;
+	/* For postponed release */
+	struct rcu_head		rcu;
+	struct list_head	contexts;
+	int			pasid;
+	struct mutex		mutex;
+	struct rb_root		sdma_list;
+};
+
+/* keep the relationship of svm_process and svm_device */
+struct svm_context {
+	struct svm_process	*process;
+	struct svm_device	*sdev;
+	struct list_head	process_head;
+	atomic_t		ref;
+};
+/*svm ioctl will include some case for HI1980 and HI1910*/
+static long svm_ioctl(struct file *file, unsigned int cmd,
+			 unsigned long arg)
+{
+	/*TODO add svm ioctl*/
+		return 0;
+}
+
+static const struct file_operations svm_fops = {
+	.owner			= THIS_MODULE,
+	.unlocked_ioctl		= svm_ioctl,
+};
+/*svm device probe this is init the svm device*/
+static int svm_device_probe(struct platform_device *pdev)
+{
+	/*TODO svm device init*/
+	return 0;
+}
+/*svm device remove this is device remove*/
+static int svm_device_remove(struct platform_device *pdev)
+{
+	/*TODO svm device remove*/
+	return 0;
+}
+
+static const struct acpi_device_id svm_acpi_match[] = {
+	{ "HSVM1980", 0},
+	{ }
+};
+MODULE_DEVICE_TABLE(acpi, svm_acpi_match);
+/*svm acpi probe and remove*/
+static struct platform_driver svm_driver = {
+	.probe	=	svm_device_probe,
+	.remove	=	svm_device_remove,
+	.driver	=	{
+		.name = SVM_DEVICE_NAME,
+		.acpi_match_table = ACPI_PTR(svm_acpi_match),
+	},
+};
+
+module_platform_driver(svm_driver);
+
+MODULE_DESCRIPTION("Hisilicon SVM driver");
+MODULE_AUTHOR("JianKang Chen <chenjiankang1@huawei.com>");
+MODULE_LICENSE("GPL v2");