106 lines
		
	
	
		
			2.2 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			106 lines
		
	
	
		
			2.2 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
// SPDX-License-Identifier: GPL-2.0
 | 
						|
#include <linux/types.h>
 | 
						|
#include <linux/string.h>
 | 
						|
#include <limits.h>
 | 
						|
#include <stdlib.h>
 | 
						|
 | 
						|
#include <internal/lib.h> // page_size
 | 
						|
#include "../../../util/machine.h"
 | 
						|
#include "../../../util/map.h"
 | 
						|
#include "../../../util/symbol.h"
 | 
						|
#include <linux/ctype.h>
 | 
						|
 | 
						|
#include <symbol/kallsyms.h>
 | 
						|
 | 
						|
#if defined(__x86_64__)
 | 
						|
 | 
						|
struct extra_kernel_map_info {
 | 
						|
	int cnt;
 | 
						|
	int max_cnt;
 | 
						|
	struct extra_kernel_map *maps;
 | 
						|
	bool get_entry_trampolines;
 | 
						|
	u64 entry_trampoline;
 | 
						|
};
 | 
						|
 | 
						|
static int add_extra_kernel_map(struct extra_kernel_map_info *mi, u64 start,
 | 
						|
				u64 end, u64 pgoff, const char *name)
 | 
						|
{
 | 
						|
	if (mi->cnt >= mi->max_cnt) {
 | 
						|
		void *buf;
 | 
						|
		size_t sz;
 | 
						|
 | 
						|
		mi->max_cnt = mi->max_cnt ? mi->max_cnt * 2 : 32;
 | 
						|
		sz = sizeof(struct extra_kernel_map) * mi->max_cnt;
 | 
						|
		buf = realloc(mi->maps, sz);
 | 
						|
		if (!buf)
 | 
						|
			return -1;
 | 
						|
		mi->maps = buf;
 | 
						|
	}
 | 
						|
 | 
						|
	mi->maps[mi->cnt].start = start;
 | 
						|
	mi->maps[mi->cnt].end   = end;
 | 
						|
	mi->maps[mi->cnt].pgoff = pgoff;
 | 
						|
	strlcpy(mi->maps[mi->cnt].name, name, KMAP_NAME_LEN);
 | 
						|
 | 
						|
	mi->cnt += 1;
 | 
						|
 | 
						|
	return 0;
 | 
						|
}
 | 
						|
 | 
						|
static int find_extra_kernel_maps(void *arg, const char *name, char type,
 | 
						|
				  u64 start)
 | 
						|
{
 | 
						|
	struct extra_kernel_map_info *mi = arg;
 | 
						|
 | 
						|
	if (!mi->entry_trampoline && kallsyms2elf_binding(type) == STB_GLOBAL &&
 | 
						|
	    !strcmp(name, "_entry_trampoline")) {
 | 
						|
		mi->entry_trampoline = start;
 | 
						|
		return 0;
 | 
						|
	}
 | 
						|
 | 
						|
	if (is_entry_trampoline(name)) {
 | 
						|
		u64 end = start + page_size;
 | 
						|
 | 
						|
		return add_extra_kernel_map(mi, start, end, 0, name);
 | 
						|
	}
 | 
						|
 | 
						|
	return 0;
 | 
						|
}
 | 
						|
 | 
						|
int machine__create_extra_kernel_maps(struct machine *machine,
 | 
						|
				      struct dso *kernel)
 | 
						|
{
 | 
						|
	struct extra_kernel_map_info mi = { .cnt = 0, };
 | 
						|
	char filename[PATH_MAX];
 | 
						|
	int ret;
 | 
						|
	int i;
 | 
						|
 | 
						|
	machine__get_kallsyms_filename(machine, filename, PATH_MAX);
 | 
						|
 | 
						|
	if (symbol__restricted_filename(filename, "/proc/kallsyms"))
 | 
						|
		return 0;
 | 
						|
 | 
						|
	ret = kallsyms__parse(filename, &mi, find_extra_kernel_maps);
 | 
						|
	if (ret)
 | 
						|
		goto out_free;
 | 
						|
 | 
						|
	if (!mi.entry_trampoline)
 | 
						|
		goto out_free;
 | 
						|
 | 
						|
	for (i = 0; i < mi.cnt; i++) {
 | 
						|
		struct extra_kernel_map *xm = &mi.maps[i];
 | 
						|
 | 
						|
		xm->pgoff = mi.entry_trampoline;
 | 
						|
		ret = machine__create_extra_kernel_map(machine, kernel, xm);
 | 
						|
		if (ret)
 | 
						|
			goto out_free;
 | 
						|
	}
 | 
						|
 | 
						|
	machine->trampolines_mapped = mi.cnt;
 | 
						|
out_free:
 | 
						|
	free(mi.maps);
 | 
						|
	return ret;
 | 
						|
}
 | 
						|
 | 
						|
#endif
 |