* Re: [PROPOSAL] MODULE_VERSION macro
2003-03-27 20:14 [PROPOSAL] MODULE_VERSION macro Matthew Wilcox
@ 2003-03-28 0:25 ` Rusty Russell
0 siblings, 0 replies; 2+ messages in thread
From: Rusty Russell @ 2003-03-28 0:25 UTC (permalink / raw)
To: Matthew Wilcox; +Cc: linux-kernel
In message <20030327201439.GA1586@parcelfarce.linux.theplanet.co.uk> you write:
> #define MODULE_VERSION(version) \
> static const char __module_version[] \
> __attribute__((section(".init.version"), unused)) = version
>
> and add the .init.version section to vmlinux.lds in the `freed after
> init' section.
After the below patch (in my re-xmit queue for Linus), how about just:
#define MODULE_VERSION(_version) MODULE_INFO(version, _version)
> The tools can catch up to use this kind of thing later; we need to
> standardise the source code to use this first.
The 0.9.10 and above have a "modinfo" which will handle it already: no
modification required.
Cheers,
Rusty.
--
Anyone who quotes me in their sig is an idiot. -- Rusty Russell.
Name: Restore modinfo section
Author: Rusty Russell
Status: Tested on 2.5.66-bk2
Depends: Module/extable-list.patch.gz
D: Restores .modinfo section, and uses it to store license and vermagic.
diff -urpN --exclude TAGS -X /home/rusty/devel/kernel/kernel-patches/current-dontdiff --minimal .26668-linux-2.5.66-bk2/include/linux/module.h .26668-linux-2.5.66-bk2.updated/include/linux/module.h
--- .26668-linux-2.5.66-bk2/include/linux/module.h 2003-03-27 15:20:11.000000000 +1100
+++ .26668-linux-2.5.66-bk2.updated/include/linux/module.h 2003-03-27 15:20:26.000000000 +1100
@@ -20,10 +20,7 @@
#include <asm/module.h>
/* Not Yet Implemented */
-#define MODULE_AUTHOR(name)
-#define MODULE_DESCRIPTION(desc)
#define MODULE_SUPPORTED_DEVICE(name)
-#define MODULE_PARM_DESC(var,desc)
#define print_modules()
/* v850 toolchain uses a `_' prefix for all user symbols */
@@ -58,12 +55,11 @@ search_extable(const struct exception_ta
unsigned long value);
#ifdef MODULE
-#define ___module_cat(a,b) a ## b
+#define ___module_cat(a,b) __mod_ ## a ## b
#define __module_cat(a,b) ___module_cat(a,b)
-/* For userspace: you can also call me... */
-#define MODULE_ALIAS(alias) \
- static const char __module_cat(__alias_,__LINE__)[] \
- __attribute__((section(".modinfo"),unused)) = "alias=" alias
+#define __MODULE_INFO(tag, name, info) \
+static const char __module_cat(name,__LINE__)[] \
+ __attribute__((section(".modinfo"),unused)) = __stringify(tag) "=" info
#define MODULE_GENERIC_TABLE(gtype,name) \
extern const struct gtype##_id __mod_##gtype##_table \
@@ -71,6 +67,21 @@ extern const struct gtype##_id __mod_##g
#define THIS_MODULE (&__this_module)
+#else /* !MODULE */
+
+#define MODULE_GENERIC_TABLE(gtype,name)
+#define __MODULE_INFO(tag, name, info)
+#define THIS_MODULE ((struct module *)0)
+#define MOD_INC_USE_COUNT do { } while (0)
+#define MOD_DEC_USE_COUNT do { } while (0)
+#endif
+
+/* Generic info of form tag = "info" */
+#define MODULE_INFO(tag, info) __MODULE_INFO(tag, tag, info)
+
+/* For userspace: you can also call me... */
+#define MODULE_ALIAS(_alias) MODULE_INFO(alias, _alias)
+
/*
* The following license idents are currently accepted as indicating free
* software modules
@@ -97,17 +108,18 @@ extern const struct gtype##_id __mod_##g
* 2. So the community can ignore bug reports including proprietary modules
* 3. So vendors can do likewise based on their own policies
*/
-#define MODULE_LICENSE(license) \
- static const char __module_license[] \
- __attribute__((section(".init.license"), unused)) = license
+#define MODULE_LICENSE(_license) MODULE_INFO(license, _license)
-#else /* !MODULE */
+/* Author, ideally of form NAME <EMAIL>[, NAME <EMAIL>]*[ and NAME <EMAIL>] */
+#define MODULE_AUTHOR(_author) MODULE_INFO(author, _author)
+
+/* What your module does. */
+#define MODULE_DESCRIPTION(_description) MODULE_INFO(description, _description)
-#define MODULE_ALIAS(alias)
-#define MODULE_GENERIC_TABLE(gtype,name)
-#define THIS_MODULE ((struct module *)0)
-#define MODULE_LICENSE(license)
-#endif
+/* One for each parameter, describing how to use it. Some files do
+ multiple of these per line, so can't just use MODULE_INFO. */
+#define MODULE_PARM_DESC(_parm, desc) \
+ __MODULE_INFO(parm, _parm, #_parm ":" desc)
#define MODULE_DEVICE_TABLE(type,name) \
MODULE_GENERIC_TABLE(type##_device,name)
diff -urpN --exclude TAGS -X /home/rusty/devel/kernel/kernel-patches/current-dontdiff --minimal .26668-linux-2.5.66-bk2/kernel/module.c .26668-linux-2.5.66-bk2.updated/kernel/module.c
--- .26668-linux-2.5.66-bk2/kernel/module.c 2003-03-27 15:20:11.000000000 +1100
+++ .26668-linux-2.5.66-bk2.updated/kernel/module.c 2003-03-27 15:20:12.000000000 +1100
@@ -914,12 +914,12 @@ EXPORT_SYMBOL_GPL(__symbol_get);
/* Change all symbols so that sh_value encodes the pointer directly. */
static int simplify_symbols(Elf_Shdr *sechdrs,
unsigned int symindex,
- unsigned int strindex,
+ const char *strtab,
unsigned int versindex,
struct module *mod)
{
Elf_Sym *sym = (void *)sechdrs[symindex].sh_addr;
- const char *strtab = (char *)sechdrs[strindex].sh_addr;
+
unsigned int i, n = sechdrs[symindex].sh_size / sizeof(Elf_Sym);
int ret = 0;
@@ -1038,13 +1038,9 @@ static inline int license_is_gpl_compati
|| strcmp(license, "Dual MPL/GPL") == 0);
}
-static void set_license(struct module *mod, Elf_Shdr *sechdrs, int licenseidx)
+static void set_license(struct module *mod, const char *license)
{
- char *license;
-
- if (licenseidx)
- license = (char *)sechdrs[licenseidx].sh_addr;
- else
+ if (!license)
license = "unspecified";
mod->license_gplok = license_is_gpl_compatible(license);
@@ -1055,6 +1051,40 @@ static void set_license(struct module *m
}
}
+/* Parse tag=value strings from .modinfo section */
+static char *next_string(char *string, unsigned long *secsize)
+{
+ /* Skip non-zero chars */
+ while (string[0]) {
+ string++;
+ if ((*secsize)-- <= 1)
+ return NULL;
+ }
+
+ /* Skip any zero padding. */
+ while (!string[0]) {
+ string++;
+ if ((*secsize)-- <= 1)
+ return NULL;
+ }
+ return string;
+}
+
+static char *get_modinfo(Elf_Shdr *sechdrs,
+ unsigned int info,
+ const char *tag)
+{
+ char *p;
+ unsigned int taglen = strlen(tag);
+ unsigned long size = sechdrs[info].sh_size;
+
+ for (p = (char *)sechdrs[info].sh_addr; p; p = next_string(p, &size)) {
+ if (strncmp(p, tag, taglen) == 0 && p[taglen] == '=')
+ return p + taglen + 1;
+ }
+ return NULL;
+}
+
/* Allocate and load the module: note that size of section 0 is always
zero, and we rely on this for optional sections. */
static struct module *load_module(void *umod,
@@ -1063,9 +1093,9 @@ static struct module *load_module(void *
{
Elf_Ehdr *hdr;
Elf_Shdr *sechdrs;
- char *secstrings, *args;
- unsigned int i, symindex, exportindex, strindex, setupindex, exindex,
- modindex, obsparmindex, licenseindex, gplindex, vmagindex,
+ char *secstrings, *args, *modmagic, *strtab = NULL;
+ unsigned int i, symindex = 0, strindex = 0, setupindex, exindex,
+ exportindex, modindex, obsparmindex, infoindex, gplindex,
crcindex, gplcrcindex, versindex;
long arglen;
struct module *mod;
@@ -1099,6 +1129,7 @@ static struct module *load_module(void *
/* Convenience variables */
sechdrs = (void *)hdr + hdr->e_shoff;
secstrings = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset;
+ sechdrs[0].sh_addr = 0;
/* And these should exist, but gcc whinges if we don't init them */
symindex = strindex = 0;
@@ -1112,6 +1143,7 @@ static struct module *load_module(void *
if (sechdrs[i].sh_type == SHT_SYMTAB) {
symindex = i;
strindex = sechdrs[i].sh_link;
+ strtab = (char *)hdr + sechdrs[strindex].sh_offset;
}
#ifndef CONFIG_MODULE_UNLOAD
/* Don't load .exit sections */
@@ -1120,12 +1152,6 @@ static struct module *load_module(void *
#endif
}
-#ifdef CONFIG_KALLSYMS
- /* Keep symbol and string tables for decoding later. */
- sechdrs[symindex].sh_flags |= SHF_ALLOC;
- sechdrs[strindex].sh_flags |= SHF_ALLOC;
-#endif
-
modindex = find_sec(hdr, sechdrs, secstrings,
".gnu.linkonce.this_module");
if (!modindex) {
@@ -1143,9 +1169,16 @@ static struct module *load_module(void *
setupindex = find_sec(hdr, sechdrs, secstrings, "__param");
exindex = find_sec(hdr, sechdrs, secstrings, "__ex_table");
obsparmindex = find_sec(hdr, sechdrs, secstrings, "__obsparm");
- licenseindex = find_sec(hdr, sechdrs, secstrings, ".init.license");
- vmagindex = find_sec(hdr, sechdrs, secstrings, "__vermagic");
versindex = find_sec(hdr, sechdrs, secstrings, "__versions");
+ infoindex = find_sec(hdr, sechdrs, secstrings, ".modinfo");
+
+ /* Don't keep modinfo section */
+ sechdrs[infoindex].sh_flags &= ~(unsigned long)SHF_ALLOC;
+#ifdef CONFIG_KALLSYMS
+ /* Keep symbol and string tables for decoding later. */
+ sechdrs[symindex].sh_flags |= SHF_ALLOC;
+ sechdrs[strindex].sh_flags |= SHF_ALLOC;
+#endif
/* Check module struct version now, before we try to use module. */
if (!check_modstruct_version(sechdrs, versindex, mod)) {
@@ -1153,14 +1186,15 @@ static struct module *load_module(void *
goto free_hdr;
}
+ modmagic = get_modinfo(sechdrs, infoindex, "vermagic");
/* This is allowed: modprobe --force will invalidate it. */
- if (!vmagindex) {
+ if (!modmagic) {
tainted |= TAINT_FORCED_MODULE;
printk(KERN_WARNING "%s: no version magic, tainting kernel.\n",
mod->name);
- } else if (!same_magic((char *)sechdrs[vmagindex].sh_addr, vermagic)) {
+ } else if (!same_magic(modmagic, vermagic)) {
printk(KERN_ERR "%s: version magic '%s' should be '%s'\n",
- mod->name, (char*)sechdrs[vmagindex].sh_addr, vermagic);
+ mod->name, modmagic, vermagic);
err = -ENOEXEC;
goto free_hdr;
}
@@ -1240,11 +1274,11 @@ static struct module *load_module(void *
/* Now we've moved module, initialize linked lists, etc. */
module_unload_init(mod);
- /* Set up license info based on contents of section */
- set_license(mod, sechdrs, licenseindex);
+ /* Set up license info based on the info section */
+ set_license(mod, get_modinfo(sechdrs, infoindex, "license"));
/* Fix up syms, so that st_value is a pointer to location. */
- err = simplify_symbols(sechdrs, symindex, strindex, versindex, mod);
+ err = simplify_symbols(sechdrs, symindex, strtab, versindex, mod);
if (err < 0)
goto cleanup;
@@ -1274,8 +1308,7 @@ static struct module *load_module(void *
for (i = 1; i < hdr->e_shnum; i++) {
const char *strtab = (char *)sechdrs[strindex].sh_addr;
if (sechdrs[i].sh_type == SHT_REL)
- err = apply_relocate(sechdrs, strtab, symindex, i,
- mod);
+ err = apply_relocate(sechdrs, strtab, symindex, i,mod);
else if (sechdrs[i].sh_type == SHT_RELA)
err = apply_relocate_add(sechdrs, strtab, symindex, i,
mod);
diff -urpN --exclude TAGS -X /home/rusty/devel/kernel/kernel-patches/current-dontdiff --minimal .26668-linux-2.5.66-bk2/scripts/modpost.c .26668-linux-2.5.66-bk2.updated/scripts/modpost.c
--- .26668-linux-2.5.66-bk2/scripts/modpost.c 2003-03-18 12:21:42.000000000 +1100
+++ .26668-linux-2.5.66-bk2.updated/scripts/modpost.c 2003-03-27 15:20:12.000000000 +1100
@@ -398,9 +398,7 @@ add_header(struct buffer *b)
buf_printf(b, "#include <linux/vermagic.h>\n");
buf_printf(b, "#include <linux/compiler.h>\n");
buf_printf(b, "\n");
- buf_printf(b, "const char vermagic[]\n");
- buf_printf(b, "__attribute__((section(\"__vermagic\"))) =\n");
- buf_printf(b, "VERMAGIC_STRING;\n");
+ buf_printf(b, "MODULE_INFO(vermagic, VERMAGIC_STRING);\n");
}
/* Record CRCs for unresolved symbols */
^ permalink raw reply [flat|nested] 2+ messages in thread