Re: [PATCH] Module loader against 2.5.46: 8/9

Rusty Russell (rusty@rustcorp.com.au)
Tue, 05 Nov 2002 14:51:39 +1100


In message <20021105001905.D1407@almesberger.net> you write:
> [ Cc: trimmed ]
>
> Rusty Russell wrote:
> > +config OBSOLETE_MODPARM
> > + bool
> > + default y
> > + help
> > + Without this option you will not be able to use module parameters on
> > + modules which have not been converted to the new module parameter
> > + system yet. If unsure, say Y.
>
> Triple negation, cool :-) How about something like
>
> You need this option to use module parameters on
> modules which have not been converted to the new module parameter
> system yet. If unsure, say Y.
>

No. I don't think that my original version wasn't clear, nor do I
have time to negate every suggestion, no matter how well meaning or
not, even if I had no better things to do, which does not seem likely,
does it not?

Point taken (although note that this option is never prompted for).
Rusty.

--
  Anyone who quotes me in their sig is an idiot. -- Rusty Russell.

Name: MODULE_PARM support for older modules Author: Rusty Russell Status: Experimental Depends: Module/param-modules.patch.gz Depends: Module/forceunload.patch.gz

D: This is the backwards compatibility code for MODULE_PARM.

diff -urpN --exclude TAGS -X /home/rusty/devel/kernel/kernel-patches/current-dontdiff --minimal .8562-linux-2.5.46/include/linux/module.h .8562-linux-2.5.46.updated/include/linux/module.h --- .8562-linux-2.5.46/include/linux/module.h 2002-11-05 14:50:29.000000000 +1100 +++ .8562-linux-2.5.46.updated/include/linux/module.h 2002-11-05 14:50:34.000000000 +1100 @@ -15,6 +15,7 @@ #include <linux/compiler.h> #include <linux/cache.h> #include <linux/kmod.h> +#include <linux/stringify.h> #include <asm/module.h> #include <asm/uaccess.h> /* For struct exception_table_entry */ @@ -274,6 +275,17 @@ extern spinlock_t modlist_lock; #define __MOD_DEC_USE_COUNT(mod) module_put(mod) #define SET_MODULE_OWNER(dev) ((dev)->owner = THIS_MODULE) +struct obsolete_modparm { char name[64]; char type[64]; void *addr; }; +#ifdef MODULE +/* DEPRECATED: Do not use. */ +#define MODULE_PARM(var,type) \ +struct obsolete_modparm __parm_##var __attribute__((section(".obsparm"))) = \ +{ __stringify(var), type }; + +#else +#define MODULE_PARM(var,type) +#endif + /* People do this inside their init routines, when the module isn't "live" yet. They should no longer be doing that, but meanwhile... */ @@ -286,11 +298,11 @@ extern spinlock_t modlist_lock; #endif #define MOD_DEC_USE_COUNT module_put(THIS_MODULE) #define try_inc_mod_count(mod) try_module_get(mod) -#define MODULE_PARM(parm,string) #define EXPORT_NO_SYMBOLS extern int module_dummy_usage; #define GET_USE_COUNT(module) (module_dummy_usage) #define MOD_IN_USE 0 +#define __MODULE_STRING(x) __stringify(x) #define __mod_between(a_start, a_len, b_start, b_len) \ (((a_start) >= (b_start) && (a_start) <= (b_start)+(b_len)) \ || ((a_start)+(a_len) >= (b_start) \ diff -urpN --exclude TAGS -X /home/rusty/devel/kernel/kernel-patches/current-dontdiff --minimal .8562-linux-2.5.46/init/Kconfig .8562-linux-2.5.46.updated/init/Kconfig --- .8562-linux-2.5.46/init/Kconfig 2002-11-05 14:50:32.000000000 +1100 +++ .8562-linux-2.5.46.updated/init/Kconfig 2002-11-05 14:51:03.000000000 +1100 @@ -135,6 +135,15 @@ config MODULE_FORCE_UNLOAD rmmod). This is mainly for kernel developers and desparate users. If unsure, say N. +config OBSOLETE_MODPARM + bool + default y + depends on MODULES + help + You need this option to use module parameters on modules which + have not been converted to the new module parameter system yet. + If unsure, say Y. + config KMOD bool "Kernel module loader" depends on MODULES @@ -150,4 +159,3 @@ config KMOD in <file:Documentation/kmod.txt>. endmenu - diff -urpN --exclude TAGS -X /home/rusty/devel/kernel/kernel-patches/current-dontdiff --minimal .8562-linux-2.5.46/kernel/module.c .8562-linux-2.5.46.updated/kernel/module.c --- .8562-linux-2.5.46/kernel/module.c 2002-11-05 14:50:32.000000000 +1100 +++ .8562-linux-2.5.46.updated/kernel/module.c 2002-11-05 14:50:34.000000000 +1100 @@ -512,6 +512,129 @@ sys_delete_module(const char *name_user, #endif /* CONFIG_MODULE_UNLOAD */ +#ifdef CONFIG_OBSOLETE_MODPARM +static int param_set_byte(const char *val, struct kernel_param *kp) +{ + char *endp; + long l; + + if (!val) return -EINVAL; + l = simple_strtol(val, &endp, 0); + if (endp == val || *endp || ((char)l != l)) + return -EINVAL; + *((char *)kp->arg) = l; + return 0; +} + +static int param_string(const char *name, const char *val, + unsigned int min, unsigned int max, + char *dest) +{ + if (strlen(val) < min || strlen(val) > max) { + printk(KERN_ERR + "Parameter %s length must be %u-%u characters\n", + name, min, max); + return -EINVAL; + } + strcpy(dest, val); + return 0; +} + +extern int set_obsolete(const char *val, struct kernel_param *kp) +{ + unsigned int min, max; + char *p, *endp; + struct obsolete_modparm *obsparm = kp->arg; + + if (!val) { + printk(KERN_ERR "Parameter %s needs an argument\n", kp->name); + return -EINVAL; + } + + /* type is: [min[-max]]{b,h,i,l,s} */ + p = obsparm->type; + min = simple_strtol(p, &endp, 10); + if (endp == obsparm->type) + min = max = 1; + else if (*endp == '-') { + p = endp+1; + max = simple_strtol(p, &endp, 10); + } else + max = min; + switch (*endp) { + case 'b': + return param_array(kp->name, val, min, max, obsparm->addr, + 1, param_set_byte); + case 'h': + return param_array(kp->name, val, min, max, obsparm->addr, + sizeof(short), param_set_short); + case 'i': + return param_array(kp->name, val, min, max, obsparm->addr, + sizeof(int), param_set_int); + case 'l': + return param_array(kp->name, val, min, max, obsparm->addr, + sizeof(long), param_set_long); + case 's': + return param_string(kp->name, val, min, max, obsparm->addr); + } + printk(KERN_ERR "Unknown obsolete parameter type %s\n", obsparm->type); + return -EINVAL; +} + +static int obsolete_params(const char *name, + char *args, + struct obsolete_modparm obsparm[], + unsigned int num, + Elf_Shdr *sechdrs, + unsigned int symindex, + const char *strtab) +{ + struct kernel_param *kp; + unsigned int i; + int ret; + + kp = kmalloc(sizeof(kp[0]) * num, GFP_KERNEL); + if (!kp) + return -ENOMEM; + + for (i = 0; i < num; i++) { + kp[i].name = obsparm[i].name; + kp[i].perm = 000; + kp[i].set = set_obsolete; + kp[i].get = NULL; + obsparm[i].addr + = (void *)find_local_symbol(sechdrs, symindex, strtab, + obsparm[i].name); + if (!obsparm[i].addr) { + printk("%s: falsely claims to have parameter %s\n", + name, obsparm[i].name); + ret = -EINVAL; + goto out; + } + kp[i].arg = &obsparm[i]; + } + + ret = parse_args(name, args, kp, num, NULL); + out: + kfree(kp); + return ret; +} +#else +static int obsolete_params(const char *name, + char *args, + struct obsolete_modparm obsparm[], + unsigned int num, + Elf_Shdr *sechdrs, + unsigned int symindex, + const char *strtab) +{ + if (num != 0) + printk(KERN_WARNING "%s: Ignoring obsolete parameters\n", + name); + return 0; +} +#endif /* CONFIG_OBSOLETE_MODPARM */ + /* Find an symbol for this module (ie. resolve internals first). It we find one, record usage. Must be holding module_mutex. */ unsigned long find_symbol_internal(Elf_Shdr *sechdrs, @@ -823,7 +946,7 @@ static struct module *load_module(void * Elf_Shdr *sechdrs; char *secstrings; unsigned int i, symindex, exportindex, strindex, setupindex, exindex, - modnameindex; + modnameindex, obsparmindex; long arglen; unsigned long common_length; struct sizes sizes, used; @@ -861,7 +984,7 @@ static struct module *load_module(void * /* May not export symbols, or have setup params, so these may not exist */ - exportindex = setupindex = 0; + exportindex = setupindex = obsparmindex = 0; /* And these should exist, but gcc whinges if we don't init them */ symindex = strindex = exindex = modnameindex = 0; @@ -897,6 +1020,11 @@ static struct module *load_module(void * /* Exception table */ DEBUGP("Exception table found in section %u\n", i); exindex = i; + } else if (strcmp(secstrings+sechdrs[i].sh_name, ".obsparm") + == 0) { + /* Obsolete MODULE_PARM() table */ + DEBUGP("Obsolete param found in section %u\n", i); + obsparmindex = i; } #ifndef CONFIG_MODULE_UNLOAD /* Don't load .exit sections */ @@ -1014,13 +1142,23 @@ static struct module *load_module(void * if (err < 0) goto cleanup; - /* Size of section 0 is 0, so this works well if no params */ - err = parse_args(mod->args, - (struct kernel_param *) - sechdrs[setupindex].sh_offset, - sechdrs[setupindex].sh_size - / sizeof(struct kernel_param), - NULL); + if (obsparmindex) { + err = obsolete_params(mod->name, mod->args, + (struct obsolete_modparm *) + sechdrs[obsparmindex].sh_offset, + sechdrs[obsparmindex].sh_size + / sizeof(struct obsolete_modparm), + sechdrs, symindex, + (char *)sechdrs[strindex].sh_offset); + } else { + /* Size of section 0 is 0, so this works well if no params */ + err = parse_args(mod->name, mod->args, + (struct kernel_param *) + sechdrs[setupindex].sh_offset, + sechdrs[setupindex].sh_size + / sizeof(struct kernel_param), + NULL); + } if (err < 0) goto cleanup; - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/