elf coredump: replace ELF_CORE_EXTRA_* macros by functions

elf_core_dump() and elf_fdpic_core_dump() use #ifdef and the corresponding
macro for hiding _multiline_ logics in functions.  This patch removes
#ifdef and replaces ELF_CORE_EXTRA_* by corresponding functions.  For
architectures not implemeonting ELF_CORE_EXTRA_*, we use weak functions in
order to reduce a range of modification.

This cleanup is for my next patches, but I think this cleanup itself is
worth doing regardless of my firnal purpose.

Signed-off-by: Daisuke HATAYAMA <d.hatayama@jp.fujitsu.com>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Greg Ungerer <gerg@snapgear.com>
Cc: Roland McGrath <roland@redhat.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: <linux-arch@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

3 files changed, 66 insertions, 48 deletions

diff --git a/arch/ia64/include/asm/elf.h b/arch/ia64/include/asm/elf.h
index 4c41656ede87..b5298eb09adb 100644
--- a/arch/ia64/include/asm/elf.h
+++ b/arch/ia64/include/asm/elf.h
@@ -219,54 +219,6 @@ do {										\
         NEW_AUX_ENT(AT_SYSINFO_EHDR, (unsigned long) GATE_EHDR);                \
 } while (0)
 
-
-/*
- * These macros parameterize elf_core_dump in fs/binfmt_elf.c to write out
- * extra segments containing the gate DSO contents.  Dumping its
- * contents makes post-mortem fully interpretable later without matching up
- * the same kernel and hardware config to see what PC values meant.
- * Dumping its extra ELF program headers includes all the other information
- * a debugger needs to easily find how the gate DSO was being used.
- */
-#define ELF_CORE_EXTRA_PHDRS            (GATE_EHDR->e_phnum)
-#define ELF_CORE_WRITE_EXTRA_PHDRS                                              \
-do {                                                                            \
-        const struct elf_phdr *const gate_phdrs =                             \
-                (const struct elf_phdr *) (GATE_ADDR + GATE_EHDR->e_phoff);   \
-        int i;                                                                  \
-        Elf64_Off ofs = 0;                                                    \
-        for (i = 0; i < GATE_EHDR->e_phnum; ++i) {                              \
-                struct elf_phdr phdr = gate_phdrs[i];                         \
-                if (phdr.p_type == PT_LOAD) {                                   \
-                        phdr.p_memsz = PAGE_ALIGN(phdr.p_memsz);              \
-                        phdr.p_filesz = phdr.p_memsz;                         \
-                        if (ofs == 0) {                                       \
-                                ofs = phdr.p_offset = offset;                 \
-                        offset += phdr.p_filesz;                                \
-                }                                                             \
-                else                                                          \
-                                phdr.p_offset = ofs;                          \
-                }                                                             \
-                else                                                          \
-                        phdr.p_offset += ofs;                                   \
-                phdr.p_paddr = 0; /* match other core phdrs */                  \
-                DUMP_WRITE(&phdr, sizeof(phdr));                                \
-        }                                                                       \
-} while (0)
-#define ELF_CORE_WRITE_EXTRA_DATA                                       \
-do {                                                                    \
-        const struct elf_phdr *const gate_phdrs =                             \
-                (const struct elf_phdr *) (GATE_ADDR + GATE_EHDR->e_phoff);   \
-        int i;                                                          \
-        for (i = 0; i < GATE_EHDR->e_phnum; ++i) {                      \
-                if (gate_phdrs[i].p_type == PT_LOAD) {                        \
-                        DUMP_WRITE((void *) gate_phdrs[i].p_vaddr,            \
-                                   PAGE_ALIGN(gate_phdrs[i].p_memsz));        \
-                        break;                                                \
-                }                                                             \
-        }                                                               \
-} while (0)
-
 /*
  * format for entries in the Global Offset Table
  */
diff --git a/arch/ia64/kernel/Makefile b/arch/ia64/kernel/Makefile
index 4138282aefa8..db10b1e378b0 100644
--- a/arch/ia64/kernel/Makefile
+++ b/arch/ia64/kernel/Makefile
@@ -45,6 +45,8 @@ endif
 obj-$(CONFIG_DMAR)              += pci-dma.o
 obj-$(CONFIG_SWIOTLB)           += pci-swiotlb.o
 
+obj-$(CONFIG_BINFMT_ELF)        += elfcore.o
+
 # fp_emulate() expects f2-f5,f16-f31 to contain the user-level state.
 CFLAGS_traps.o  += -mfixed-range=f2-f5,f16-f31
 
diff --git a/arch/ia64/kernel/elfcore.c b/arch/ia64/kernel/elfcore.c
new file mode 100644
index 000000000000..57a2298a8581
--- /dev/null
+++ b/arch/ia64/kernel/elfcore.c
@@ -0,0 +1,64 @@
+#include <linux/elf.h>
+#include <linux/coredump.h>
+#include <linux/fs.h>
+#include <linux/mm.h>
+
+#include <asm/elf.h>
+
+
+Elf64_Half elf_core_extra_phdrs(void)
+{
+        return GATE_EHDR->e_phnum;
+}
+
+int elf_core_write_extra_phdrs(struct file *file, loff_t offset, size_t *size,
+                               unsigned long limit)
+{
+        const struct elf_phdr *const gate_phdrs =
+                (const struct elf_phdr *) (GATE_ADDR + GATE_EHDR->e_phoff);
+        int i;
+        Elf64_Off ofs = 0;
+
+        for (i = 0; i < GATE_EHDR->e_phnum; ++i) {
+                struct elf_phdr phdr = gate_phdrs[i];
+
+                if (phdr.p_type == PT_LOAD) {
+                        phdr.p_memsz = PAGE_ALIGN(phdr.p_memsz);
+                        phdr.p_filesz = phdr.p_memsz;
+                        if (ofs == 0) {
+                                ofs = phdr.p_offset = offset;
+                                offset += phdr.p_filesz;
+                        } else {
+                                phdr.p_offset = ofs;
+                        }
+                } else {
+                        phdr.p_offset += ofs;
+                }
+                phdr.p_paddr = 0; /* match other core phdrs */
+                *size += sizeof(phdr);
+                if (*size > limit || !dump_write(file, &phdr, sizeof(phdr)))
+                        return 0;
+        }
+        return 1;
+}
+
+int elf_core_write_extra_data(struct file *file, size_t *size,
+                              unsigned long limit)
+{
+        const struct elf_phdr *const gate_phdrs =
+                (const struct elf_phdr *) (GATE_ADDR + GATE_EHDR->e_phoff);
+        int i;
+
+        for (i = 0; i < GATE_EHDR->e_phnum; ++i) {
+                if (gate_phdrs[i].p_type == PT_LOAD) {
+                        void *addr = (void *)gate_phdrs[i].p_vaddr;
+                        size_t memsz = PAGE_ALIGN(gate_phdrs[i].p_memsz);
+
+                        *size += memsz;
+                        if (*size > limit || !dump_write(file, addr, memsz))
+                                return 0;
+                        break;
+                }
+        }
+        return 1;
+}