linux-kernel - RE: [PATCH 2/3] module: wrapper for symbol name.

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Date:	Fri, 5 Feb 2016 06:45:14 +0000
From:	平松雅巳 / HIRAMATU，MASAMI 
	<masami.hiramatsu.pt@...achi.com>
To:	"'Rusty Russell'" <rusty@...tcorp.com.au>,
	"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>
CC:	Weilong Chen <chenweilong@...wei.com>,
	"\"PDate:Wed\"@ozlabs.org" <"PDate:Wed"@ozlabs.org>,
	"stable@...nel.org" <stable@...nel.org>
Subject: RE: [PATCH 2/3] module: wrapper for symbol name.

From: Rusty Russell [mailto:rusty@...tcorp.com.au]
>
>This trivial wrapper adds clarity and makes the following patch
>smaller.
>
>Cc: stable@...nel.org
>Signed-off-by: Rusty Russell <rusty@...tcorp.com.au>

Looks good to me.

Reviewed-by: Masami Hiramatsu <masami.hiramatsu.pt@...achi.com>

Thanks!

>---
> kernel/module.c | 26 +++++++++++++++-----------
> 1 file changed, 15 insertions(+), 11 deletions(-)
>
>diff --git a/kernel/module.c b/kernel/module.c
>index 2149f7003e49..1e79d8157712 100644
>--- a/kernel/module.c
>+++ b/kernel/module.c
>@@ -3627,6 +3627,11 @@ static inline int is_arm_mapping_symbol(const char *str)
> 	       && (str[2] == '\0' || str[2] == '.');
> }
>
>+static const char *symname(struct module *mod, unsigned int symnum)
>+{
>+	return mod->strtab + mod->symtab[symnum].st_name;
>+}
>+
> static const char *get_ksymbol(struct module *mod,
> 			       unsigned long addr,
> 			       unsigned long *size,
>@@ -3649,15 +3654,15 @@ static const char *get_ksymbol(struct module *mod,
>
> 		/* We ignore unnamed symbols: they're uninformative
> 		 * and inserted at a whim. */
>+		if (*symname(mod, i) == '\0'
>+		    || is_arm_mapping_symbol(symname(mod, i)))
>+			continue;
>+
> 		if (mod->symtab[i].st_value <= addr
>-		    && mod->symtab[i].st_value > mod->symtab[best].st_value
>-		    && *(mod->strtab + mod->symtab[i].st_name) != '\0'
>-		    && !is_arm_mapping_symbol(mod->strtab + mod->symtab[i].st_name))
>+		    && mod->symtab[i].st_value > mod->symtab[best].st_value)
> 			best = i;
> 		if (mod->symtab[i].st_value > addr
>-		    && mod->symtab[i].st_value < nextval
>-		    && *(mod->strtab + mod->symtab[i].st_name) != '\0'
>-		    && !is_arm_mapping_symbol(mod->strtab + mod->symtab[i].st_name))
>+		    && mod->symtab[i].st_value < nextval)
> 			nextval = mod->symtab[i].st_value;
> 	}
>
>@@ -3668,7 +3673,7 @@ static const char *get_ksymbol(struct module *mod,
> 		*size = nextval - mod->symtab[best].st_value;
> 	if (offset)
> 		*offset = addr - mod->symtab[best].st_value;
>-	return mod->strtab + mod->symtab[best].st_name;
>+	return symname(mod, best);
> }
>
> /* For kallsyms to ask for address resolution.  NULL means not found.  Careful
>@@ -3763,8 +3768,7 @@ int module_get_kallsym(unsigned int symnum, unsigned long *value, char *type,
> 		if (symnum < mod->num_symtab) {
> 			*value = mod->symtab[symnum].st_value;
> 			*type = mod->symtab[symnum].st_info;
>-			strlcpy(name, mod->strtab + mod->symtab[symnum].st_name,
>-				KSYM_NAME_LEN);
>+			strlcpy(name, symname(mod, symnum), KSYM_NAME_LEN);
> 			strlcpy(module_name, mod->name, MODULE_NAME_LEN);
> 			*exported = is_exported(name, *value, mod);
> 			preempt_enable();
>@@ -3781,7 +3785,7 @@ static unsigned long mod_find_symname(struct module *mod, const char *name)
> 	unsigned int i;
>
> 	for (i = 0; i < mod->num_symtab; i++)
>-		if (strcmp(name, mod->strtab+mod->symtab[i].st_name) == 0 &&
>+		if (strcmp(name, symname(mod, i)) == 0 &&
> 		    mod->symtab[i].st_info != 'U')
> 			return mod->symtab[i].st_value;
> 	return 0;
>@@ -3825,7 +3829,7 @@ int module_kallsyms_on_each_symbol(int (*fn)(void *, const char *,
> 		if (mod->state == MODULE_STATE_UNFORMED)
> 			continue;
> 		for (i = 0; i < mod->num_symtab; i++) {
>-			ret = fn(data, mod->strtab + mod->symtab[i].st_name,
>+			ret = fn(data, symname(mod, i),
> 				 mod, mod->symtab[i].st_value);
> 			if (ret != 0)
> 				return ret;
>--
>2.5.0