[PATCH] Kexec / Kdump: Unify elf note code

The elf note saving code is currently duplicated over several
architectures.  This cleanup patch simply adds code to a common file and
then replaces the arch-specific code with calls to the newly added code.

The only drawback with this approach is that s390 doesn't fully support
kexec-on-panic which for that arch leads to introduction of unused code.

Signed-off-by: Magnus Damm <magnus@valinux.co.jp>
Cc: Vivek Goyal <vgoyal@in.ibm.com>
Cc: Andi Kleen <ak@suse.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 2 insertions, 67 deletions

diff --git a/arch/x86_64/kernel/crash.c b/arch/x86_64/kernel/crash.c
index 3525f884af82..95a7a2c13131 100644
--- a/arch/x86_64/kernel/crash.c
+++ b/arch/x86_64/kernel/crash.c
@@ -28,71 +28,6 @@
 /* This keeps a track of which one is crashing cpu. */
 static int crashing_cpu;
 
-static u32 *append_elf_note(u32 *buf, char *name, unsigned type,
-                                                void *data, size_t data_len)
-{
-        struct elf_note note;
-
-        note.n_namesz = strlen(name) + 1;
-        note.n_descsz = data_len;
-        note.n_type   = type;
-        memcpy(buf, &note, sizeof(note));
-        buf += (sizeof(note) +3)/4;
-        memcpy(buf, name, note.n_namesz);
-        buf += (note.n_namesz + 3)/4;
-        memcpy(buf, data, note.n_descsz);
-        buf += (note.n_descsz + 3)/4;
-
-        return buf;
-}
-
-static void final_note(u32 *buf)
-{
-        struct elf_note note;
-
-        note.n_namesz = 0;
-        note.n_descsz = 0;
-        note.n_type   = 0;
-        memcpy(buf, &note, sizeof(note));
-}
-
-static void crash_save_this_cpu(struct pt_regs *regs, int cpu)
-{
-        struct elf_prstatus prstatus;
-        u32 *buf;
-
-        if ((cpu < 0) || (cpu >= NR_CPUS))
-                return;
-
-        /* Using ELF notes here is opportunistic.
-         * I need a well defined structure format
-         * for the data I pass, and I need tags
-         * on the data to indicate what information I have
-         * squirrelled away.  ELF notes happen to provide
-         * all of that, no need to invent something new.
-         */
-
-        buf = (u32*)per_cpu_ptr(crash_notes, cpu);
-
-        if (!buf)
-                return;
-
-        memset(&prstatus, 0, sizeof(prstatus));
-        prstatus.pr_pid = current->pid;
-        elf_core_copy_regs(&prstatus.pr_reg, regs);
-        buf = append_elf_note(buf, "CORE", NT_PRSTATUS, &prstatus,
-                                        sizeof(prstatus));
-        final_note(buf);
-}
-
-static void crash_save_self(struct pt_regs *regs)
-{
-        int cpu;
-
-        cpu = smp_processor_id();
-        crash_save_this_cpu(regs, cpu);
-}
-
 #ifdef CONFIG_SMP
 static atomic_t waiting_for_crash_ipi;
 
@@ -117,7 +52,7 @@ static int crash_nmi_callback(struct notifier_block *self,
                 return NOTIFY_STOP;
         local_irq_disable();
 
-        crash_save_this_cpu(regs, cpu);
+        crash_save_cpu(regs, cpu);
         disable_local_APIC();
         atomic_dec(&waiting_for_crash_ipi);
         /* Assume hlt works */
@@ -196,5 +131,5 @@ void machine_crash_shutdown(struct pt_regs *regs)
 
         disable_IO_APIC();
 
-        crash_save_self(regs);
+        crash_save_cpu(regs, smp_processor_id());
 }