sh: Tidy up the dwarf module helpers.

This enables us to build the dwarf unwinder both with modules enabled and
disabled in addition to reducing code size in the latter case. The
helpers are also consolidated, and modified to resemble the BUG module
helpers.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>
diff --git a/arch/sh/kernel/dwarf.c b/arch/sh/kernel/dwarf.c
index c274039..718286b 100644
--- a/arch/sh/kernel/dwarf.c
+++ b/arch/sh/kernel/dwarf.c
@@ -20,6 +20,7 @@
 #include <linux/list.h>
 #include <linux/mempool.h>
 #include <linux/mm.h>
+#include <linux/elf.h>
 #include <asm/dwarf.h>
 #include <asm/unwinder.h>
 #include <asm/sections.h>
@@ -895,8 +896,8 @@
  *
  *	Parse the information in a .eh_frame section.
  */
-int dwarf_parse_section(char *eh_frame_start, char *eh_frame_end,
-			struct module *mod)
+static int dwarf_parse_section(char *eh_frame_start, char *eh_frame_end,
+			       struct module *mod)
 {
 	u32 entry_type;
 	void *p, *entry;
@@ -959,14 +960,47 @@
 	return err;
 }
 
+#ifdef CONFIG_MODULES
+int module_dwarf_finalize(const Elf_Ehdr *hdr, const Elf_Shdr *sechdrs,
+			  struct module *me)
+{
+	unsigned int i, err;
+	unsigned long start, end;
+	char *secstrings = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset;
+
+	start = end = 0;
+
+	for (i = 1; i < hdr->e_shnum; i++) {
+		/* Alloc bit cleared means "ignore it." */
+		if ((sechdrs[i].sh_flags & SHF_ALLOC)
+		    && !strcmp(secstrings+sechdrs[i].sh_name, ".eh_frame")) {
+			start = sechdrs[i].sh_addr;
+			end = start + sechdrs[i].sh_size;
+			break;
+		}
+	}
+
+	/* Did we find the .eh_frame section? */
+	if (i != hdr->e_shnum) {
+		err = dwarf_parse_section((char *)start, (char *)end, me);
+		if (err) {
+			printk(KERN_WARNING "%s: failed to parse DWARF info\n",
+			       me->name);
+			return err;
+		}
+	}
+
+	return 0;
+}
+
 /**
- *	dwarf_module_unload - remove FDE/CIEs associated with @mod
+ *	module_dwarf_cleanup - remove FDE/CIEs associated with @mod
  *	@mod: the module that is being unloaded
  *
  *	Remove any FDEs and CIEs from the global lists that came from
  *	@mod's .eh_frame section because @mod is being unloaded.
  */
-void dwarf_module_unload(struct module *mod)
+void module_dwarf_cleanup(struct module *mod)
 {
 	struct dwarf_fde *fde;
 	struct dwarf_cie *cie;
@@ -1004,6 +1038,7 @@
 
 	spin_unlock_irqrestore(&dwarf_fde_lock, flags);
 }
+#endif /* CONFIG_MODULES */
 
 /**
  *	dwarf_unwinder_init - initialise the dwarf unwinder