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#ifndef UFTRACE_MCOUNT_DYNAMIC_H
#define UFTRACE_MCOUNT_DYNAMIC_H
#include <link.h>
#include <stdlib.h>
#ifdef HAVE_LIBCAPSTONE
#include <capstone/capstone.h>
#endif
#include "utils/symbol.h"
#ifndef PAGE_SIZE
#define PAGE_SIZE 4096
#endif
#define PAGE_ADDR(a) ((void *)((a) & ~(PAGE_SIZE - 1)))
#define PAGE_LEN(a, l) (a + l - (unsigned long)PAGE_ADDR(a))
#define XRAY_SECT "xray_instr_map"
#define MCOUNTLOC_SECT "__mcount_loc"
#define PATCHABLE_SECT "__patchable_function_entries"
/* target instrumentation function it needs to call */
extern void __fentry__(void);
extern void __dentry__(void);
extern void __xray_entry(void);
extern void __xray_exit(void);
struct xray_instr_map {
uint64_t address;
uint64_t function;
uint8_t kind;
uint8_t always_instrument;
uint8_t version;
uint8_t padding[13];
};
enum mcount_dynamic_type {
DYNAMIC_NONE,
DYNAMIC_PG,
DYNAMIC_FENTRY,
DYNAMIC_FENTRY_NOP,
DYNAMIC_XRAY,
DYNAMIC_PATCHABLE,
};
__maybe_unused static const char *mdi_type_names[] = {
"none", "pg", "fentry", "fentry-nop", "xray", "fpatchable",
};
struct mcount_dynamic_info {
struct mcount_dynamic_info *next;
struct uftrace_mmap *map;
unsigned long base_addr;
unsigned long text_addr;
int text_size;
unsigned long trampoline;
struct list_head bad_syms;
enum mcount_dynamic_type type;
void *patch_target;
unsigned nr_patch_target;
};
struct mcount_disasm_engine {
#ifdef HAVE_LIBCAPSTONE
csh engine;
#endif
};
#define INSTRUMENT_SUCCESS 0
#define INSTRUMENT_FAILED -1
#define INSTRUMENT_SKIPPED -2
/*
* Supposing the size of smallest conditional branch is 2 byte.
* We can replace, at most, 3 of them by the instrumentation
* instruction.
*/
#define MAX_COND_BRANCH 3
int mcount_dynamic_update(struct uftrace_sym_info *sinfo, char *patch_funcs,
enum uftrace_pattern_type ptype);
void mcount_dynamic_dlopen(struct uftrace_sym_info *sinfo, struct dl_phdr_info *info, char *path,
struct uftrace_mmap *map);
void mcount_dynamic_finish(void);
struct mcount_orig_insn {
struct rb_node node;
unsigned long addr;
void *orig;
void *insn;
int orig_size;
int insn_size;
};
struct cond_branch_info {
/* where the insn starts in the out-of-line exec buffer*/
unsigned long insn_index;
/* the original target address of the branch */
unsigned long branch_target;
unsigned long insn_addr;
unsigned long insn_size;
};
/*
* mcount_disasm_info - information for dynamic patch
* @sym : symbol for the function
* @addr : currently targeted function address.
* @insns : byte array to store instruction.
* @orig_size : size of original instructions
* @copy_size : size of copied instructions (may be modified)
* @modified : whether instruction is changed
* @has_jump : whether jump_target should be added
*/
struct mcount_disasm_info {
struct uftrace_symbol *sym;
unsigned long addr;
unsigned char insns[64];
int orig_size;
int copy_size;
bool modified;
bool has_jump;
bool has_intel_cet;
uint8_t nr_branch;
struct cond_branch_info branch_info[MAX_COND_BRANCH];
};
void mcount_save_code(struct mcount_disasm_info *info, unsigned call_size, void *jmp_insn,
unsigned jmp_size);
void *mcount_find_code(unsigned long addr);
struct mcount_orig_insn *mcount_find_insn(unsigned long addr);
void mcount_freeze_code(void);
/* these should be implemented for each architecture */
int mcount_setup_trampoline(struct mcount_dynamic_info *adi);
void mcount_cleanup_trampoline(struct mcount_dynamic_info *mdi);
int mcount_patch_func(struct mcount_dynamic_info *mdi, struct uftrace_symbol *sym,
struct mcount_disasm_engine *disasm, unsigned min_size);
void mcount_disasm_init(struct mcount_disasm_engine *disasm);
void mcount_disasm_finish(struct mcount_disasm_engine *disasm);
int mcount_arch_branch_table_size(struct mcount_disasm_info *info);
void mcount_arch_patch_branch(struct mcount_disasm_info *info, struct mcount_orig_insn *orig);
struct dynamic_bad_symbol {
struct list_head list;
struct uftrace_symbol *sym;
bool reverted;
};
struct dynamic_bad_symbol *mcount_find_badsym(struct mcount_dynamic_info *mdi, unsigned long addr);
bool mcount_add_badsym(struct mcount_dynamic_info *mdi, unsigned long callsite,
unsigned long target);
void mcount_free_badsym(struct mcount_dynamic_info *mdi);
#endif /* UFTRACE_MCOUNT_DYNAMIC_H */
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