OpenWrt – Rev 1
?pathlinks?
--- a/arch/mips/Makefile
+++ b/arch/mips/Makefile
@@ -90,8 +90,13 @@ all-$(CONFIG_SYS_SUPPORTS_ZBOOT)+= vmlin
cflags-y += -G 0 -mno-abicalls -fno-pic -pipe -mno-branch-likely
cflags-y += -msoft-float
LDFLAGS_vmlinux += -G 0 -static -n -nostdlib --gc-sections
+ifdef CONFIG_64BIT
KBUILD_AFLAGS_MODULE += -mlong-calls
KBUILD_CFLAGS_MODULE += -mlong-calls
+else
+KBUILD_AFLAGS_MODULE += -mno-long-calls
+KBUILD_CFLAGS_MODULE += -mno-long-calls
+endif
ifndef CONFIG_FUNCTION_TRACER
KBUILD_CFLAGS_KERNEL += -ffunction-sections -fdata-sections
--- a/arch/mips/include/asm/module.h
+++ b/arch/mips/include/asm/module.h
@@ -11,6 +11,11 @@ struct mod_arch_specific {
const struct exception_table_entry *dbe_start;
const struct exception_table_entry *dbe_end;
struct mips_hi16 *r_mips_hi16_list;
+
+ void *phys_plt_tbl;
+ void *virt_plt_tbl;
+ unsigned int phys_plt_offset;
+ unsigned int virt_plt_offset;
};
typedef uint8_t Elf64_Byte; /* Type for a 8-bit quantity. */
--- a/arch/mips/kernel/module.c
+++ b/arch/mips/kernel/module.c
@@ -43,14 +43,222 @@ struct mips_hi16 {
static LIST_HEAD(dbe_list);
static DEFINE_SPINLOCK(dbe_lock);
-#ifdef MODULE_START
+/*
+ * Get the potential max trampolines size required of the init and
+ * non-init sections. Only used if we cannot find enough contiguous
+ * physically mapped memory to put the module into.
+ */
+static unsigned int
+get_plt_size(const Elf_Ehdr *hdr, const Elf_Shdr *sechdrs,
+ const char *secstrings, unsigned int symindex, bool is_init)
+{
+ unsigned long ret = 0;
+ unsigned int i, j;
+ Elf_Sym *syms;
+
+ /* Everything marked ALLOC (this includes the exported symbols) */
+ for (i = 1; i < hdr->e_shnum; ++i) {
+ unsigned int info = sechdrs[i].sh_info;
+
+ if (sechdrs[i].sh_type != SHT_REL
+ && sechdrs[i].sh_type != SHT_RELA)
+ continue;
+
+ /* 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 it's called *.init*, and we're not init, we're
+ not interested */
+ if ((strstr(secstrings + sechdrs[i].sh_name, ".init") != 0)
+ != is_init)
+ continue;
+
+ syms = (Elf_Sym *) sechdrs[symindex].sh_addr;
+ if (sechdrs[i].sh_type == SHT_REL) {
+ Elf_Mips_Rel *rel = (void *) sechdrs[i].sh_addr;
+ unsigned int size = sechdrs[i].sh_size / sizeof(*rel);
+
+ for (j = 0; j < size; ++j) {
+ Elf_Sym *sym;
+
+ if (ELF_MIPS_R_TYPE(rel[j]) != R_MIPS_26)
+ continue;
+
+ sym = syms + ELF_MIPS_R_SYM(rel[j]);
+ if (!is_init && sym->st_shndx != SHN_UNDEF)
+ continue;
+
+ ret += 4 * sizeof(int);
+ }
+ } else {
+ Elf_Mips_Rela *rela = (void *) sechdrs[i].sh_addr;
+ unsigned int size = sechdrs[i].sh_size / sizeof(*rela);
+
+ for (j = 0; j < size; ++j) {
+ Elf_Sym *sym;
+
+ if (ELF_MIPS_R_TYPE(rela[j]) != R_MIPS_26)
+ continue;
+
+ sym = syms + ELF_MIPS_R_SYM(rela[j]);
+ if (!is_init && sym->st_shndx != SHN_UNDEF)
+ continue;
+
+ ret += 4 * sizeof(int);
+ }
+ }
+ }
+
+ return ret;
+}
+
+#ifndef MODULE_START
+static void *alloc_phys(unsigned long size)
+{
+ unsigned order;
+ struct page *page;
+ struct page *p;
+
+ size = PAGE_ALIGN(size);
+ order = get_order(size);
+
+ page = alloc_pages(GFP_KERNEL | __GFP_NORETRY | __GFP_NOWARN |
+ __GFP_THISNODE, order);
+ if (!page)
+ return NULL;
+
+ split_page(page, order);
+
+ for (p = page + (size >> PAGE_SHIFT); p < page + (1 << order); ++p)
+ __free_page(p);
+
+ return page_address(page);
+}
+#endif
+
+static void free_phys(void *ptr, unsigned long size)
+{
+ struct page *page;
+ struct page *end;
+
+ page = virt_to_page(ptr);
+ end = page + (PAGE_ALIGN(size) >> PAGE_SHIFT);
+
+ for (; page < end; ++page)
+ __free_page(page);
+}
+
+
void *module_alloc(unsigned long size)
{
+#ifdef MODULE_START
return __vmalloc_node_range(size, 1, MODULE_START, MODULE_END,
GFP_KERNEL, PAGE_KERNEL, NUMA_NO_NODE,
__builtin_return_address(0));
+#else
+ void *ptr;
+
+ if (size == 0)
+ return NULL;
+
+ ptr = alloc_phys(size);
+
+ /* If we failed to allocate physically contiguous memory,
+ * fall back to regular vmalloc. The module loader code will
+ * create jump tables to handle long jumps */
+ if (!ptr)
+ return vmalloc(size);
+
+ return ptr;
+#endif
}
+
+static inline bool is_phys_addr(void *ptr)
+{
+#ifdef CONFIG_64BIT
+ return (KSEGX((unsigned long)ptr) == CKSEG0);
+#else
+ return (KSEGX(ptr) == KSEG0);
#endif
+}
+
+/* Free memory returned from module_alloc */
+void module_free(struct module *mod, void *module_region)
+{
+ if (is_phys_addr(module_region)) {
+ if (mod->module_init == module_region)
+ free_phys(module_region, mod->init_size);
+ else if (mod->module_core == module_region)
+ free_phys(module_region, mod->core_size);
+ else
+ BUG();
+ } else {
+ vfree(module_region);
+ }
+}
+
+static void *__module_alloc(int size, bool phys)
+{
+ void *ptr;
+
+ if (phys)
+ ptr = kmalloc(size, GFP_KERNEL);
+ else
+ ptr = vmalloc(size);
+ return ptr;
+}
+
+static void __module_free(void *ptr)
+{
+ if (is_phys_addr(ptr))
+ kfree(ptr);
+ else
+ vfree(ptr);
+}
+
+int module_frob_arch_sections(Elf_Ehdr *hdr, Elf_Shdr *sechdrs,
+ char *secstrings, struct module *mod)
+{
+ unsigned int symindex = 0;
+ unsigned int core_size, init_size;
+ int i;
+
+ mod->arch.phys_plt_offset = 0;
+ mod->arch.virt_plt_offset = 0;
+ mod->arch.phys_plt_tbl = NULL;
+ mod->arch.virt_plt_tbl = NULL;
+
+ if (IS_ENABLED(CONFIG_64BIT))
+ return 0;
+
+ for (i = 1; i < hdr->e_shnum; i++)
+ if (sechdrs[i].sh_type == SHT_SYMTAB)
+ symindex = i;
+
+ core_size = get_plt_size(hdr, sechdrs, secstrings, symindex, false);
+ init_size = get_plt_size(hdr, sechdrs, secstrings, symindex, true);
+
+ if ((core_size + init_size) == 0)
+ return 0;
+
+ mod->arch.phys_plt_tbl = __module_alloc(core_size + init_size, 1);
+ if (!mod->arch.phys_plt_tbl)
+ return -ENOMEM;
+
+ mod->arch.virt_plt_tbl = __module_alloc(core_size + init_size, 0);
+ if (!mod->arch.virt_plt_tbl) {
+ __module_free(mod->arch.phys_plt_tbl);
+ mod->arch.phys_plt_tbl = NULL;
+ return -ENOMEM;
+ }
+
+ return 0;
+}
int apply_r_mips_none(struct module *me, u32 *location, Elf_Addr v)
{
@@ -64,8 +272,39 @@ static int apply_r_mips_32_rel(struct mo
return 0;
}
+static Elf_Addr add_plt_entry_to(unsigned *plt_offset,
+ void *start, Elf_Addr v)
+{
+ unsigned *tramp = start + *plt_offset;
+ *plt_offset += 4 * sizeof(int);
+
+ /* adjust carry for addiu */
+ if (v & 0x00008000)
+ v += 0x10000;
+
+ tramp[0] = 0x3c190000 | (v >> 16); /* lui t9, hi16 */
+ tramp[1] = 0x27390000 | (v & 0xffff); /* addiu t9, t9, lo16 */
+ tramp[2] = 0x03200008; /* jr t9 */
+ tramp[3] = 0x00000000; /* nop */
+
+ return (Elf_Addr) tramp;
+}
+
+static Elf_Addr add_plt_entry(struct module *me, void *location, Elf_Addr v)
+{
+ if (is_phys_addr(location))
+ return add_plt_entry_to(&me->arch.phys_plt_offset,
+ me->arch.phys_plt_tbl, v);
+ else
+ return add_plt_entry_to(&me->arch.virt_plt_offset,
+ me->arch.virt_plt_tbl, v);
+
+}
+
static int apply_r_mips_26_rel(struct module *me, u32 *location, Elf_Addr v)
{
+ u32 ofs = *location & 0x03ffffff;
+
if (v % 4) {
pr_err("module %s: dangerous R_MIPS_26 REL relocation\n",
me->name);
@@ -73,14 +312,17 @@ static int apply_r_mips_26_rel(struct mo
}
if ((v & 0xf0000000) != (((unsigned long)location + 4) & 0xf0000000)) {
- printk(KERN_ERR
- "module %s: relocation overflow\n",
- me->name);
- return -ENOEXEC;
+ v = add_plt_entry(me, location, v + (ofs << 2));
+ if (!v) {
+ printk(KERN_ERR
+ "module %s: relocation overflow\n", me->name);
+ return -ENOEXEC;
+ }
+ ofs = 0;
}
*location = (*location & ~0x03ffffff) |
- ((*location + (v >> 2)) & 0x03ffffff);
+ ((ofs + (v >> 2)) & 0x03ffffff);
return 0;
}
@@ -287,9 +529,36 @@ int module_finalize(const Elf_Ehdr *hdr,
list_add(&me->arch.dbe_list, &dbe_list);
spin_unlock_irq(&dbe_lock);
}
+
+ /* Get rid of the fixup trampoline if we're running the module
+ * from physically mapped address space */
+ if (me->arch.phys_plt_offset == 0) {
+ __module_free(me->arch.phys_plt_tbl);
+ me->arch.phys_plt_tbl = NULL;
+ }
+ if (me->arch.virt_plt_offset == 0) {
+ __module_free(me->arch.virt_plt_tbl);
+ me->arch.virt_plt_tbl = NULL;
+ }
+
return 0;
}
+void module_arch_freeing_init(struct module *mod)
+{
+ if (mod->state == MODULE_STATE_LIVE)
+ return;
+
+ if (mod->arch.phys_plt_tbl) {
+ __module_free(mod->arch.phys_plt_tbl);
+ mod->arch.phys_plt_tbl = NULL;
+ }
+ if (mod->arch.virt_plt_tbl) {
+ __module_free(mod->arch.virt_plt_tbl);
+ mod->arch.virt_plt_tbl = NULL;
+ }
+}
+
void module_arch_cleanup(struct module *mod)
{
spin_lock_irq(&dbe_lock);