Revert "mm: Add a flag MAP_VA32BIT for mmap"

ascend inclusion
category: bugfix
bugzilla: NA
CVE: NA

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

It's specific code for ascend, so remove it.

This reverts commit 25cf3abca447947a56e74ee9393943e9a3adf8a8.
Signed-off-by: NYang Yingliang <yangyingliang@huawei.com>

arch/arm64/include/asm/processor.h

@@ -70,8 +70,6 @@
 #define TASK_SIZE		TASK_SIZE_64
 #endif /* CONFIG_COMPAT */
 
-#define MMAP_TOP_4G_SIZE	(0x100000000UL)
-
 #define TASK_UNMAPPED_BASE	(PAGE_ALIGN(TASK_SIZE / 4))
 
 #define STACK_TOP_MAX		TASK_SIZE_64

fs/hugetlbfs/inode.c

@@ -215,10 +215,6 @@ hugetlb_get_unmapped_area(struct file *file, unsigned long addr,
 
 	if (addr) {
 		addr = ALIGN(addr, huge_page_size(h));
-
-		if (!mmap_va32bit_check(addr, len, flags))
-			return -ENOMEM;
-
 		vma = find_vma(mm, addr);
 		if (TASK_SIZE - len >= addr &&
 		    (!vma || addr + len <= vm_start_gap(vma)))
@@ -231,9 +227,6 @@ hugetlb_get_unmapped_area(struct file *file, unsigned long addr,
 	info.high_limit = TASK_SIZE;
 	info.align_mask = PAGE_MASK & ~huge_page_mask(h);
 	info.align_offset = 0;
-
-	mmap_va32bit_set_limit(&info, flags);
-
 	return vm_unmapped_area(&info);
 }
 #endif

include/linux/mm.h

@@ -2355,29 +2355,6 @@ struct vm_unmapped_area_info {
 	unsigned long align_offset;
 };
 
-
-#ifdef CONFIG_ARCH_ASCEND
-
-extern int mmap_va32bit_check(unsigned long addr, unsigned long len,
-			      unsigned long flags);
-extern void mmap_va32bit_set_limit(struct vm_unmapped_area_info *info,
-				   unsigned long flags);
-
-#else
-
-static inline int mmap_va32bit_check(unsigned long addr, unsigned long len,
-				     unsigned long flags)
-{
-	return 1;
-}
-
-static inline void mmap_va32bit_set_limit(struct vm_unmapped_area_info *info,
-					  unsigned long flags)
-{
-}
-
-#endif
-
 extern unsigned long unmapped_area(struct vm_unmapped_area_info *info);
 extern unsigned long unmapped_area_topdown(struct vm_unmapped_area_info *info);
 

include/uapi/asm-generic/mman.h

@@ -14,7 +14,6 @@
 #define MAP_STACK	0x20000		/* give out an address that is best suited for process/thread stacks */
 #define MAP_HUGETLB	0x40000		/* create a huge page mapping */
 #define MAP_SYNC	0x80000		/* perform synchronous page faults for the mapping */
-#define MAP_VA32BIT	0x0200
 
 /* Bits [26:31] are reserved, see mman-common.h for MAP_HUGETLB usage */
 

mm/mmap.c

@@ -1841,38 +1841,6 @@ unsigned long mmap_region(struct file *file, unsigned long addr,
 	return error;
 }
 
-#ifdef CONFIG_ARCH_ASCEND
-
-int mmap_va32bit_check(unsigned long addr, unsigned long len,
-		       unsigned long flags)
-{
-	return !(!(flags & MAP_VA32BIT) &&
-		((addr + len) > (TASK_SIZE - MMAP_TOP_4G_SIZE)) &&
-		(addr < TASK_SIZE));
-}
-
-
-void mmap_va32bit_set_limit(struct vm_unmapped_area_info *info,
-			    unsigned long flags)
-{
-	const unsigned long high_limit = TASK_SIZE;
-	const unsigned long divide = TASK_SIZE - MMAP_TOP_4G_SIZE;
-
-	if (info == NULL)
-		return;
-
-	if (flags & MAP_VA32BIT) {
-		info->low_limit = divide;
-		info->high_limit = high_limit;
-	} else {
-		/* low_limit do not need set */
-		if (info->high_limit > divide)
-			info->high_limit = divide;
-	}
-}
-
-#endif
-
 unsigned long unmapped_area(struct vm_unmapped_area_info *info)
 {
 	/*
@@ -2103,10 +2071,6 @@ arch_get_unmapped_area(struct file *filp, unsigned long addr,
 
 	if (addr) {
 		addr = PAGE_ALIGN(addr);
-
-		if (!mmap_va32bit_check(addr, len, flags))
-			return -ENOMEM;
-
 		vma = find_vma_prev(mm, addr, &prev);
 		if (TASK_SIZE - len >= addr && addr >= mmap_min_addr &&
 		    (!vma || addr + len <= vm_start_gap(vma)) &&
@@ -2119,9 +2083,6 @@ arch_get_unmapped_area(struct file *filp, unsigned long addr,
 	info.low_limit = mm->mmap_base;
 	info.high_limit = TASK_SIZE;
 	info.align_mask = 0;
-
-	mmap_va32bit_set_limit(&info, flags);
-
 	return vm_unmapped_area(&info);
 }
 #endif
@@ -2151,10 +2112,6 @@ arch_get_unmapped_area_topdown(struct file *filp, const unsigned long addr0,
 	/* requesting a specific address */
 	if (addr) {
 		addr = PAGE_ALIGN(addr);
-
-		if (!mmap_va32bit_check(addr, len, flags))
-			return -ENOMEM;
-
 		vma = find_vma_prev(mm, addr, &prev);
 		if (TASK_SIZE - len >= addr && addr >= mmap_min_addr &&
 				(!vma || addr + len <= vm_start_gap(vma)) &&
@@ -2167,9 +2124,6 @@ arch_get_unmapped_area_topdown(struct file *filp, const unsigned long addr0,
 	info.low_limit = max(PAGE_SIZE, mmap_min_addr);
 	info.high_limit = mm->mmap_base;
 	info.align_mask = 0;
-
-	mmap_va32bit_set_limit(&info, flags);
-
 	addr = vm_unmapped_area(&info);
 
 	/*
@@ -2183,9 +2137,6 @@ arch_get_unmapped_area_topdown(struct file *filp, const unsigned long addr0,
 		info.flags = 0;
 		info.low_limit = TASK_UNMAPPED_BASE;
 		info.high_limit = TASK_SIZE;
-
-		mmap_va32bit_set_limit(&info, flags);
-
 		addr = vm_unmapped_area(&info);
 	}