module: refactor load_module part 5
1) Extract out the relocation loop into apply_relocations
2) Extract license and version checks into check_module_license_and_versions
3) Extract icache flushing into flush_module_icache
4) Move __obsparm warning into find_module_sections
5) Move license setting into check_modinfo.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
diff --git a/kernel/module.c b/kernel/module.c
index 241bc41..b536db8 100644
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -1698,6 +1698,39 @@
return ret;
}
+static int apply_relocations(struct module *mod,
+ Elf_Ehdr *hdr,
+ Elf_Shdr *sechdrs,
+ unsigned int symindex,
+ unsigned int strindex)
+{
+ unsigned int i;
+ int err = 0;
+
+ /* Now do relocations. */
+ for (i = 1; i < hdr->e_shnum; i++) {
+ const char *strtab = (char *)sechdrs[strindex].sh_addr;
+ unsigned int info = sechdrs[i].sh_info;
+
+ /* Not a valid relocation section? */
+ if (info >= hdr->e_shnum)
+ continue;
+
+ /* Don't bother with non-allocated sections */
+ if (!(sechdrs[info].sh_flags & SHF_ALLOC))
+ continue;
+
+ if (sechdrs[i].sh_type == SHT_REL)
+ 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);
+ if (err < 0)
+ break;
+ }
+ return err;
+}
+
/* Additional bytes needed by arch in front of individual sections */
unsigned int __weak arch_mod_section_prepend(struct module *mod,
unsigned int section)
@@ -2179,6 +2212,10 @@
" the quality is unknown, you have been warned.\n",
mod->name);
}
+
+ /* Set up license info based on the info section */
+ set_license(mod, get_modinfo(sechdrs, infoindex, "license"));
+
return 0;
}
@@ -2245,6 +2282,10 @@
sizeof(*mod->ftrace_callsites),
&mod->num_ftrace_callsites);
#endif
+
+ if (section_addr(hdr, sechdrs, secstrings, "__obsparm"))
+ printk(KERN_WARNING "%s: Ignoring obsolete parameters\n",
+ mod->name);
}
static struct module *move_module(struct module *mod,
@@ -2311,6 +2352,60 @@
return mod;
}
+static int check_module_license_and_versions(struct module *mod,
+ Elf_Shdr *sechdrs)
+{
+ /*
+ * ndiswrapper is under GPL by itself, but loads proprietary modules.
+ * Don't use add_taint_module(), as it would prevent ndiswrapper from
+ * using GPL-only symbols it needs.
+ */
+ if (strcmp(mod->name, "ndiswrapper") == 0)
+ add_taint(TAINT_PROPRIETARY_MODULE);
+
+ /* driverloader was caught wrongly pretending to be under GPL */
+ if (strcmp(mod->name, "driverloader") == 0)
+ add_taint_module(mod, TAINT_PROPRIETARY_MODULE);
+
+#ifdef CONFIG_MODVERSIONS
+ if ((mod->num_syms && !mod->crcs)
+ || (mod->num_gpl_syms && !mod->gpl_crcs)
+ || (mod->num_gpl_future_syms && !mod->gpl_future_crcs)
+#ifdef CONFIG_UNUSED_SYMBOLS
+ || (mod->num_unused_syms && !mod->unused_crcs)
+ || (mod->num_unused_gpl_syms && !mod->unused_gpl_crcs)
+#endif
+ ) {
+ return try_to_force_load(mod,
+ "no versions for exported symbols");
+ }
+#endif
+ return 0;
+}
+
+static void flush_module_icache(const struct module *mod)
+{
+ mm_segment_t old_fs;
+
+ /* flush the icache in correct context */
+ old_fs = get_fs();
+ set_fs(KERNEL_DS);
+
+ /*
+ * Flush the instruction cache, since we've played with text.
+ * Do it before processing of module parameters, so the module
+ * can provide parameter accessor functions of its own.
+ */
+ if (mod->module_init)
+ flush_icache_range((unsigned long)mod->module_init,
+ (unsigned long)mod->module_init
+ + mod->init_size);
+ flush_icache_range((unsigned long)mod->module_core,
+ (unsigned long)mod->module_core + mod->core_size);
+
+ set_fs(old_fs);
+}
+
/* Allocate and load the module: note that size of section 0 is always
zero, and we rely on this for optional sections. */
static noinline struct module *load_module(void __user *umod,
@@ -2331,8 +2426,6 @@
struct _ddebug *debug = NULL;
unsigned int num_debug = 0;
- mm_segment_t old_fs;
-
DEBUGP("load_module: umod=%p, len=%lu, uargs=%p\n",
umod, len, uargs);
@@ -2453,20 +2546,13 @@
if (err)
goto free_init;
- /* Set up license info based on the info section */
- set_license(mod, get_modinfo(sechdrs, infoindex, "license"));
+ /* Now we've got everything in the final locations, we can
+ * find optional sections. */
+ find_module_sections(mod, hdr, sechdrs, secstrings);
- /*
- * ndiswrapper is under GPL by itself, but loads proprietary modules.
- * Don't use add_taint_module(), as it would prevent ndiswrapper from
- * using GPL-only symbols it needs.
- */
- if (strcmp(mod->name, "ndiswrapper") == 0)
- add_taint(TAINT_PROPRIETARY_MODULE);
-
- /* driverloader was caught wrongly pretending to be under GPL */
- if (strcmp(mod->name, "driverloader") == 0)
- add_taint_module(mod, TAINT_PROPRIETARY_MODULE);
+ err = check_module_license_and_versions(mod, sechdrs);
+ if (err)
+ goto free_unload;
/* Set up MODINFO_ATTR fields */
setup_modinfo(mod, sechdrs, infoindex);
@@ -2477,47 +2563,9 @@
if (err < 0)
goto cleanup;
- /* Now we've got everything in the final locations, we can
- * find optional sections. */
- find_module_sections(mod, hdr, sechdrs, secstrings);
-
-#ifdef CONFIG_MODVERSIONS
- if ((mod->num_syms && !mod->crcs)
- || (mod->num_gpl_syms && !mod->gpl_crcs)
- || (mod->num_gpl_future_syms && !mod->gpl_future_crcs)
-#ifdef CONFIG_UNUSED_SYMBOLS
- || (mod->num_unused_syms && !mod->unused_crcs)
- || (mod->num_unused_gpl_syms && !mod->unused_gpl_crcs)
-#endif
- ) {
- err = try_to_force_load(mod,
- "no versions for exported symbols");
- if (err)
- goto cleanup;
- }
-#endif
-
- /* Now do relocations. */
- for (i = 1; i < hdr->e_shnum; i++) {
- const char *strtab = (char *)sechdrs[strindex].sh_addr;
- unsigned int info = sechdrs[i].sh_info;
-
- /* Not a valid relocation section? */
- if (info >= hdr->e_shnum)
- continue;
-
- /* Don't bother with non-allocated sections */
- if (!(sechdrs[info].sh_flags & SHF_ALLOC))
- continue;
-
- if (sechdrs[i].sh_type == SHT_REL)
- 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);
- if (err < 0)
- goto cleanup;
- }
+ err = apply_relocations(mod, hdr, sechdrs, symindex, strindex);
+ if (err < 0)
+ goto cleanup;
/* Set up and sort exception table */
mod->extable = section_objs(hdr, sechdrs, secstrings, "__ex_table",
@@ -2541,28 +2589,9 @@
if (err < 0)
goto cleanup;
- /* flush the icache in correct context */
- old_fs = get_fs();
- set_fs(KERNEL_DS);
-
- /*
- * Flush the instruction cache, since we've played with text.
- * Do it before processing of module parameters, so the module
- * can provide parameter accessor functions of its own.
- */
- if (mod->module_init)
- flush_icache_range((unsigned long)mod->module_init,
- (unsigned long)mod->module_init
- + mod->init_size);
- flush_icache_range((unsigned long)mod->module_core,
- (unsigned long)mod->module_core + mod->core_size);
-
- set_fs(old_fs);
+ flush_module_icache(mod);
mod->args = args;
- if (section_addr(hdr, sechdrs, secstrings, "__obsparm"))
- printk(KERN_WARNING "%s: Ignoring obsolete parameters\n",
- mod->name);
/* Now sew it into the lists so we can get lockdep and oops
* info during argument parsing. Noone should access us, since
@@ -2619,6 +2648,7 @@
module_arch_cleanup(mod);
cleanup:
free_modinfo(mod);
+ free_unload:
module_unload_free(mod);
free_init:
module_free(mod, mod->module_init);