tracing/probes: Add fetch{,_size} member into deref fetch method

The deref fetch methods access a memory region but it assumes that
it's a kernel memory since uprobes does not support them.

Add ->fetch and ->fetch_size member in order to provide a proper
access methods for supporting uprobes.

Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: zhangwei(Jovi) <jovi.zhangwei@huawei.com>
Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Signed-off-by: Hyeoncheol Lee <cheol.lee@lge.com>
[namhyung@kernel.org: Split original patch into pieces as requested]
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
This commit is contained in:
Hyeoncheol Lee 2013-07-01 13:44:32 +09:00 committed by Steven Rostedt
parent 1301a44e77
commit 3925f4a5af

View file

@ -184,6 +184,8 @@ __kprobes void FETCH_FUNC_NAME(memory, string_size)(struct pt_regs *regs,
struct deref_fetch_param {
struct fetch_param orig;
long offset;
fetch_func_t fetch;
fetch_func_t fetch_size;
};
#define DEFINE_FETCH_deref(type) \
@ -195,13 +197,26 @@ __kprobes void FETCH_FUNC_NAME(deref, type)(struct pt_regs *regs, \
call_fetch(&dprm->orig, regs, &addr); \
if (addr) { \
addr += dprm->offset; \
fetch_memory_##type(regs, (void *)addr, dest); \
dprm->fetch(regs, (void *)addr, dest); \
} else \
*(type *)dest = 0; \
}
DEFINE_BASIC_FETCH_FUNCS(deref)
DEFINE_FETCH_deref(string)
DEFINE_FETCH_deref(string_size)
__kprobes void FETCH_FUNC_NAME(deref, string_size)(struct pt_regs *regs,
void *data, void *dest)
{
struct deref_fetch_param *dprm = data;
unsigned long addr;
call_fetch(&dprm->orig, regs, &addr);
if (addr && dprm->fetch_size) {
addr += dprm->offset;
dprm->fetch_size(regs, (void *)addr, dest);
} else
*(string_size *)dest = 0;
}
static __kprobes void update_deref_fetch_param(struct deref_fetch_param *data)
{
@ -477,6 +492,9 @@ static int parse_probe_arg(char *arg, const struct fetch_type *t,
return -ENOMEM;
dprm->offset = offset;
dprm->fetch = t->fetch[FETCH_MTD_memory];
dprm->fetch_size = get_fetch_size_function(t,
dprm->fetch, ftbl);
ret = parse_probe_arg(arg, t2, &dprm->orig, is_return,
is_kprobe);
if (ret)