arm64/ascend: Enable DvPP mmap features for Ascend Platform

ascend inclusion
category: feature
bugzilla: https://gitee.com/openeuler/kernel/issues/I4M24Q
CVE: NA

-------------------------------------------------

The DvPP means Davinci Video Pre-Processor, add new config
ASCEND_FEATURES and DVPP_MMAP to enable the DvPP features
for Ascend platform.

The DvPP could only use a limit range of virtual address, just like the
Ascend310/910 could only use the 4 GB range of virtual address, so add
a new mmap flag which is named MAP_DVPP to use the DvPP processor by
mmap syscall, the new flag is only valid for Ascend platform.

You should alloc the memory for dvpp like this:

addr = mmap(NULL, length, PROT_READ, MAP_ANONYMOUS | MAP_DVPP, -1, 0);
Signed-off-by: NLijun Fang <fanglijun3@huawei.com>
Reviewed-by: NWeilong Chen <chenweilong@huawei.com>
Signed-off-by: NZheng Zengkai <zhengzengkai@huawei.com>

arch/arm64/Kconfig

@@ -1994,6 +1994,35 @@ config STACKPROTECTOR_PER_TASK
 	def_bool y
 	depends on STACKPROTECTOR && CC_HAVE_STACKPROTECTOR_SYSREG
 
+menuconfig ASCEND_FEATURES
+	bool "Support Ascend Features"
+	depends on ARM64
+	help
+	  The Ascend chip use the Hisilicon DaVinci architecture, and mainly
+	  focus on AI and machine leanring area, contains many external features.
+
+	  Enable this config to enable selective list of these features.
+
+	  If unsure, say Y
+
+if ASCEND_FEATURES
+
+config ASCEND_DVPP_MMAP
+	bool "Enable support for the DvPP mmap"
+	default y
+	help
+	  The DvPP means Davinci Video Pre-Processor, are mainly consist of VDEC
+	  (Video Decode), VENC(Video Encode), JPEG D/E (Decode/Encode), PNGD
+	  (PNG Decode) and VPC (Video Process) processors.
+
+	  The DvPP could only use a limit range of virtual address, just like the
+	  Ascend310/910 could only use the limit range of virtual address (default
+	  4 GB), so add a new mmap flag which is named MAP_DVPP to allocate the
+	  special memory for DvPP processor, the new flag is only valid for Ascend
+	  platform.
+
+endif
+
 endmenu
 
 menu "Boot options"

drivers/char/svm.c

@@ -1433,6 +1433,9 @@ static unsigned long svm_get_unmapped_area(struct file *file,
 
 		addr = ALIGN(addr, len);
 
+		if (dvpp_mmap_check(addr, len, flags))
+			return -ENOMEM;
+
 		vma = find_vma(mm, addr);
 		if (TASK_SIZE - len >= addr && addr >= mmap_min_addr &&
 		   (vma == NULL || addr + len <= vm_start_gap(vma)))
@@ -1442,7 +1445,8 @@ static unsigned long svm_get_unmapped_area(struct file *file,
 	info.flags = VM_UNMAPPED_AREA_TOPDOWN;
 	info.length = len;
 	info.low_limit = max(PAGE_SIZE, mmap_min_addr);
-	info.high_limit = mm->mmap_base;
+	info.high_limit = ((mm->mmap_base <= DVPP_MMAP_BASE) ?
+				mm->mmap_base : DVPP_MMAP_BASE);
 	info.align_mask = ((len >> PAGE_SHIFT) - 1) << PAGE_SHIFT;
 	info.align_offset = pgoff << PAGE_SHIFT;
 
@@ -1452,7 +1456,10 @@ static unsigned long svm_get_unmapped_area(struct file *file,
 		VM_BUG_ON(addr != -ENOMEM);
 		info.flags = 0;
 		info.low_limit = TASK_UNMAPPED_BASE;
-		info.high_limit = TASK_SIZE;
+		info.high_limit = DVPP_MMAP_BASE;
+
+		if (enable_mmap_dvpp)
+			dvpp_mmap_get_area(&info, flags);
 
 		addr = vm_unmapped_area(&info);
 	}

fs/hugetlbfs/inode.c

@@ -254,6 +254,10 @@ hugetlb_get_unmapped_area_bottomup(struct file *file, unsigned long addr,
 	info.high_limit = TASK_SIZE;
 	info.align_mask = PAGE_MASK & ~huge_page_mask(h);
 	info.align_offset = 0;
+
+	if (enable_mmap_dvpp)
+		dvpp_mmap_get_area(&info, flags);
+
 	return vm_unmapped_area(&info);
 }
 
@@ -270,6 +274,10 @@ hugetlb_get_unmapped_area_topdown(struct file *file, unsigned long addr,
 	info.high_limit = current->mm->mmap_base;
 	info.align_mask = PAGE_MASK & ~huge_page_mask(h);
 	info.align_offset = 0;
+
+	if (enable_mmap_dvpp)
+		dvpp_mmap_get_area(&info, flags);
+
 	addr = vm_unmapped_area(&info);
 
 	/*
@@ -283,6 +291,10 @@ hugetlb_get_unmapped_area_topdown(struct file *file, unsigned long addr,
 		info.flags = 0;
 		info.low_limit = current->mm->mmap_base;
 		info.high_limit = TASK_SIZE;
+
+		if (enable_mmap_dvpp)
+			dvpp_mmap_get_area(&info, flags);
+
 		addr = vm_unmapped_area(&info);
 	}
 
@@ -310,6 +322,10 @@ hugetlb_get_unmapped_area(struct file *file, unsigned long addr,
 
 	if (addr) {
 		addr = ALIGN(addr, huge_page_size(h));
+
+		if (dvpp_mmap_check(addr, len, flags))
+			return -ENOMEM;
+
 		vma = find_vma(mm, addr);
 		if (TASK_SIZE - len >= addr &&
 		    (!vma || addr + len <= vm_start_gap(vma)))

include/linux/mman.h

@@ -23,6 +23,70 @@ static inline void set_vm_checknode(vm_flags_t *vm_flags, unsigned long flags)
 {}
 #endif
 
+extern int enable_mmap_dvpp;
+/*
+ * Enable MAP_32BIT for Ascend Platform
+ */
+#ifdef CONFIG_ASCEND_DVPP_MMAP
+
+#define MAP_DVPP	0x200
+
+#define DVPP_MMAP_SIZE	(0x100000000UL)
+#define DVPP_MMAP_BASE (TASK_SIZE - DVPP_MMAP_SIZE)
+
+static inline int dvpp_mmap_check(unsigned long addr, unsigned long len,
+								unsigned long flags)
+{
+	if (enable_mmap_dvpp && (flags & MAP_DVPP) &&
+		(addr < DVPP_MMAP_BASE + DVPP_MMAP_SIZE) &&
+			(addr > DVPP_MMAP_BASE))
+		return -EINVAL;
+	else
+		return 0;
+}
+
+static inline void dvpp_mmap_get_area(struct vm_unmapped_area_info *info,
+									unsigned long flags)
+{
+	if (flags & MAP_DVPP) {
+		info->low_limit = DVPP_MMAP_BASE;
+		info->high_limit = DVPP_MMAP_BASE + DVPP_MMAP_SIZE;
+	} else {
+		info->low_limit = max(info->low_limit, TASK_UNMAPPED_BASE);
+		info->high_limit = min(info->high_limit, DVPP_MMAP_BASE);
+	}
+}
+
+static inline int dvpp_mmap_zone(unsigned long addr)
+{
+	if (addr >= DVPP_MMAP_BASE)
+		return 1;
+	else
+		return 0;
+}
+#else
+
+#define MAP_DVPP (0)
+
+static inline int dvpp_mmap_check(unsigned long addr, unsigned long len,
+								unsigned long flags)
+{
+	return 0;
+}
+
+static inline void dvpp_mmap_get_area(struct vm_unmapped_area_info *info,
+									unsigned long flags)
+{
+}
+
+static inline int dvpp_mmap_zone(unsigned long addr) { return 0; }
+
+#define DVPP_MMAP_BASE (0)
+
+#define DVPP_MMAP_SIZE (0)
+
+#endif
+
 /*
  * Arrange for legacy / undefined architecture specific flags to be
  * ignored by mmap handling code.

mm/mmap.c

@@ -2409,6 +2409,10 @@ arch_get_unmapped_area(struct file *filp, unsigned long addr,
 
 	if (addr) {
 		addr = PAGE_ALIGN(addr);
+
+		if (dvpp_mmap_check(addr, len, flags))
+			return -ENOMEM;
+
 		vma = find_vma_prev(mm, addr, &prev);
 		if (mmap_end - len >= addr && addr >= mmap_min_addr &&
 		    (!vma || addr + len <= vm_start_gap(vma)) &&
@@ -2422,6 +2426,10 @@ arch_get_unmapped_area(struct file *filp, unsigned long addr,
 	info.high_limit = mmap_end;
 	info.align_mask = 0;
 	info.align_offset = 0;
+
+	if (enable_mmap_dvpp)
+		dvpp_mmap_get_area(&info, flags);
+
 	return vm_unmapped_area(&info);
 }
 #endif
@@ -2451,6 +2459,10 @@ arch_get_unmapped_area_topdown(struct file *filp, unsigned long addr,
 	/* requesting a specific address */
 	if (addr) {
 		addr = PAGE_ALIGN(addr);
+
+		if (dvpp_mmap_check(addr, len, flags))
+			return -ENOMEM;
+
 		vma = find_vma_prev(mm, addr, &prev);
 		if (mmap_end - len >= addr && addr >= mmap_min_addr &&
 				(!vma || addr + len <= vm_start_gap(vma)) &&
@@ -2464,6 +2476,10 @@ arch_get_unmapped_area_topdown(struct file *filp, unsigned long addr,
 	info.high_limit = arch_get_mmap_base(addr, mm->mmap_base);
 	info.align_mask = 0;
 	info.align_offset = 0;
+
+	if (enable_mmap_dvpp)
+		dvpp_mmap_get_area(&info, flags);
+
 	addr = vm_unmapped_area(&info);
 
 	/*
@@ -2477,6 +2493,10 @@ arch_get_unmapped_area_topdown(struct file *filp, unsigned long addr,
 		info.flags = 0;
 		info.low_limit = TASK_UNMAPPED_BASE;
 		info.high_limit = mmap_end;
+
+		if (enable_mmap_dvpp)
+			dvpp_mmap_get_area(&info, flags);
+
 		addr = vm_unmapped_area(&info);
 	}
 
@@ -4069,3 +4089,23 @@ static int __meminit init_reserve_notifier(void)
 	return 0;
 }
 subsys_initcall(init_reserve_notifier);
+
+
+/*
+ *  Enable the MAP_32BIT (mmaps and hugetlb).
+ */
+int enable_mmap_dvpp __read_mostly;
+
+#ifdef CONFIG_ASCEND_DVPP_MMAP
+
+static int __init ascend_enable_mmap_dvpp(char *s)
+{
+	enable_mmap_dvpp = 1;
+
+	pr_info("Ascend enable dvpp mmap features\n");
+
+	return 1;
+}
+__setup("enable_mmap_dvpp", ascend_enable_mmap_dvpp);
+
+#endif