[PATCH v2 3/5] powerpc/fadump: remove dependency with CONFIG_KEXEC

From: Hari Bathini
Date: Fri Nov 25 2016 - 06:54:40 EST


Now that crashkernel parameter parsing and vmcoreinfo related code is
moved under CONFIG_CRASH_CORE instead of CONFIG_KEXEC_CORE, remove
dependency with CONFIG_KEXEC for CONFIG_FA_DUMP. While here, get rid
of definitions of fadump_append_elf_note() & fadump_final_note()
functions to reuse similar functions compiled under CONFIG_CRASH_CORE.

Signed-off-by: Hari Bathini <hbathini@xxxxxxxxxxxxxxxxxx>
---
arch/powerpc/Kconfig | 10 ++++++----
arch/powerpc/include/asm/fadump.h | 2 ++
arch/powerpc/kernel/crash.c | 2 --
arch/powerpc/kernel/fadump.c | 34 +++-------------------------------
arch/powerpc/kernel/setup-common.c | 5 +++++
5 files changed, 16 insertions(+), 37 deletions(-)

diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index 65fba4c..644703f 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -479,21 +479,23 @@ config RELOCATABLE
load address of the kernel (eg. u-boot/mkimage).

config CRASH_DUMP
- bool "Build a kdump crash kernel"
+ bool "Build a dump capture kernel"
depends on PPC64 || 6xx || FSL_BOOKE || (44x && !SMP)
select RELOCATABLE if (PPC64 && !COMPILE_TEST) || 44x || FSL_BOOKE
help
- Build a kernel suitable for use as a kdump capture kernel.
+ Build a kernel suitable for use as a dump capture kernel.
The same kernel binary can be used as production kernel and dump
capture kernel.

config FA_DUMP
bool "Firmware-assisted dump"
- depends on PPC64 && PPC_RTAS && CRASH_DUMP && KEXEC
+ depends on PPC64 && PPC_RTAS
+ select CRASH_CORE
+ select CRASH_DUMP
help
A robust mechanism to get reliable kernel crash dump with
assistance from firmware. This approach does not use kexec,
- instead firmware assists in booting the kdump kernel
+ instead firmware assists in booting the capture kernel
while preserving memory contents. Firmware-assisted dump
is meant to be a kdump replacement offering robustness and
speed not possible without system firmware assistance.
diff --git a/arch/powerpc/include/asm/fadump.h b/arch/powerpc/include/asm/fadump.h
index 0031806..60b9108 100644
--- a/arch/powerpc/include/asm/fadump.h
+++ b/arch/powerpc/include/asm/fadump.h
@@ -73,6 +73,8 @@
reg_entry++; \
})

+extern int crashing_cpu;
+
/* Kernel Dump section info */
struct fadump_section {
__be32 request_flag;
diff --git a/arch/powerpc/kernel/crash.c b/arch/powerpc/kernel/crash.c
index 47b63de..cbabb5a 100644
--- a/arch/powerpc/kernel/crash.c
+++ b/arch/powerpc/kernel/crash.c
@@ -43,8 +43,6 @@
#define IPI_TIMEOUT 10000
#define REAL_MODE_TIMEOUT 10000

-/* This keeps a track of which one is the crashing cpu. */
-int crashing_cpu = -1;
static int time_to_dump;

#define CRASH_HANDLER_MAX 3
diff --git a/arch/powerpc/kernel/fadump.c b/arch/powerpc/kernel/fadump.c
index 8f0c7c5..db0b339 100644
--- a/arch/powerpc/kernel/fadump.c
+++ b/arch/powerpc/kernel/fadump.c
@@ -486,34 +486,6 @@ fadump_read_registers(struct fadump_reg_entry *reg_entry, struct pt_regs *regs)
return reg_entry;
}

-static u32 *fadump_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 fadump_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 u32 *fadump_regs_to_elf_notes(u32 *buf, struct pt_regs *regs)
{
struct elf_prstatus prstatus;
@@ -524,8 +496,8 @@ static u32 *fadump_regs_to_elf_notes(u32 *buf, struct pt_regs *regs)
* prstatus.pr_pid = ????
*/
elf_core_copy_kernel_regs(&prstatus.pr_reg, regs);
- buf = fadump_append_elf_note(buf, KEXEC_CORE_NOTE_NAME, NT_PRSTATUS,
- &prstatus, sizeof(prstatus));
+ buf = append_elf_note(buf, CRASH_CORE_NOTE_NAME, NT_PRSTATUS,
+ &prstatus, sizeof(prstatus));
return buf;
}

@@ -666,7 +638,7 @@ static int __init fadump_build_cpu_notes(const struct fadump_mem_struct *fdm)
note_buf = fadump_regs_to_elf_notes(note_buf, &regs);
}
}
- fadump_final_note(note_buf);
+ final_note(note_buf);

if (fdh) {
pr_debug("Updating elfcore header (%llx) with cpu notes\n",
diff --git a/arch/powerpc/kernel/setup-common.c b/arch/powerpc/kernel/setup-common.c
index 270ee30..d322527 100644
--- a/arch/powerpc/kernel/setup-common.c
+++ b/arch/powerpc/kernel/setup-common.c
@@ -116,6 +116,11 @@ int ppc_do_canonicalize_irqs;
EXPORT_SYMBOL(ppc_do_canonicalize_irqs);
#endif

+#if defined(CONFIG_KEXEC) || defined(CONFIG_FA_DUMP)
+/* This keeps a track of which one is the crashing cpu. */
+int crashing_cpu = -1;
+#endif
+
/* also used by kexec */
void machine_shutdown(void)
{