140 lines
		
	
	
		
			3.1 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			140 lines
		
	
	
		
			3.1 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  * Copyright 2017, Anshuman Khandual, IBM Corp.
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|  * Licensed under GPLv2.
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|  *
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|  * Works on architectures which support 128TB virtual
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|  * address range and beyond.
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|  */
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| #include <stdio.h>
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| #include <stdlib.h>
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| #include <string.h>
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| #include <unistd.h>
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| #include <errno.h>
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| #include <sys/mman.h>
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| #include <sys/time.h>
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| 
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| /*
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|  * Maximum address range mapped with a single mmap()
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|  * call is little bit more than 16GB. Hence 16GB is
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|  * chosen as the single chunk size for address space
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|  * mapping.
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|  */
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| #define MAP_CHUNK_SIZE   17179869184UL /* 16GB */
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| 
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| /*
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|  * Address space till 128TB is mapped without any hint
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|  * and is enabled by default. Address space beyond 128TB
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|  * till 512TB is obtained by passing hint address as the
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|  * first argument into mmap() system call.
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|  *
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|  * The process heap address space is divided into two
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|  * different areas one below 128TB and one above 128TB
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|  * till it reaches 512TB. One with size 128TB and the
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|  * other being 384TB.
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|  *
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|  * On Arm64 the address space is 256TB and no high mappings
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|  * are supported so far.
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|  */
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| 
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| #define NR_CHUNKS_128TB   8192UL /* Number of 16GB chunks for 128TB */
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| #define NR_CHUNKS_256TB   (NR_CHUNKS_128TB * 2UL)
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| #define NR_CHUNKS_384TB   (NR_CHUNKS_128TB * 3UL)
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| 
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| #define ADDR_MARK_128TB  (1UL << 47) /* First address beyond 128TB */
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| #define ADDR_MARK_256TB  (1UL << 48) /* First address beyond 256TB */
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| 
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| #ifdef __aarch64__
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| #define HIGH_ADDR_MARK  ADDR_MARK_256TB
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| #define HIGH_ADDR_SHIFT 49
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| #define NR_CHUNKS_LOW   NR_CHUNKS_256TB
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| #define NR_CHUNKS_HIGH  0
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| #else
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| #define HIGH_ADDR_MARK  ADDR_MARK_128TB
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| #define HIGH_ADDR_SHIFT 48
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| #define NR_CHUNKS_LOW   NR_CHUNKS_128TB
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| #define NR_CHUNKS_HIGH  NR_CHUNKS_384TB
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| #endif
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| 
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| static char *hind_addr(void)
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| {
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| 	int bits = HIGH_ADDR_SHIFT + rand() % (63 - HIGH_ADDR_SHIFT);
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| 
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| 	return (char *) (1UL << bits);
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| }
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| 
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| static int validate_addr(char *ptr, int high_addr)
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| {
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| 	unsigned long addr = (unsigned long) ptr;
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| 
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| 	if (high_addr) {
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| 		if (addr < HIGH_ADDR_MARK) {
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| 			printf("Bad address %lx\n", addr);
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| 			return 1;
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| 		}
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| 		return 0;
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| 	}
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| 
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| 	if (addr > HIGH_ADDR_MARK) {
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| 		printf("Bad address %lx\n", addr);
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| 		return 1;
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| 	}
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| 	return 0;
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| }
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| 
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| static int validate_lower_address_hint(void)
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| {
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| 	char *ptr;
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| 
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| 	ptr = mmap((void *) (1UL << 45), MAP_CHUNK_SIZE, PROT_READ |
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| 			PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
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| 
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| 	if (ptr == MAP_FAILED)
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| 		return 0;
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| 
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| 	return 1;
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| }
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| 
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| int main(int argc, char *argv[])
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| {
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| 	char *ptr[NR_CHUNKS_LOW];
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| 	char *hptr[NR_CHUNKS_HIGH];
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| 	char *hint;
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| 	unsigned long i, lchunks, hchunks;
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| 
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| 	for (i = 0; i < NR_CHUNKS_LOW; i++) {
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| 		ptr[i] = mmap(NULL, MAP_CHUNK_SIZE, PROT_READ | PROT_WRITE,
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| 					MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
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| 
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| 		if (ptr[i] == MAP_FAILED) {
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| 			if (validate_lower_address_hint())
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| 				return 1;
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| 			break;
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| 		}
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| 
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| 		if (validate_addr(ptr[i], 0))
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| 			return 1;
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| 	}
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| 	lchunks = i;
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| 
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| 	for (i = 0; i < NR_CHUNKS_HIGH; i++) {
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| 		hint = hind_addr();
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| 		hptr[i] = mmap(hint, MAP_CHUNK_SIZE, PROT_READ | PROT_WRITE,
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| 					MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
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| 
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| 		if (hptr[i] == MAP_FAILED)
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| 			break;
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| 
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| 		if (validate_addr(hptr[i], 1))
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| 			return 1;
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| 	}
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| 	hchunks = i;
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| 
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| 	for (i = 0; i < lchunks; i++)
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| 		munmap(ptr[i], MAP_CHUNK_SIZE);
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| 
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| 	for (i = 0; i < hchunks; i++)
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| 		munmap(hptr[i], MAP_CHUNK_SIZE);
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| 
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| 	return 0;
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| }
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