[POWERPC] coredump: Add SPU elf notes to coredump.

This patch adds SPU elf notes to the coredump. It creates a separate note
for each of /regs, /fpcr, /lslr, /decr, /decr_status, /mem, /signal1,
/signal1_type, /signal2, /signal2_type, /event_mask, /event_status,
/mbox_info, /ibox_info, /wbox_info, /dma_info, /proxydma_info, /object-id.

A new macro, ARCH_HAVE_EXTRA_NOTES, was created for architectures to
specify they have extra elf core notes.

A new macro, ELF_CORE_EXTRA_NOTES_SIZE, was created so the size of the
additional notes could be calculated and added to the notes phdr entry.

A new macro, ELF_CORE_WRITE_EXTRA_NOTES, was created so the new notes
would be written after the existing notes.

The SPU coredump code resides in spufs. Stub functions are provided in the
kernel which are hooked into the spufs code which does the actual work via
register_arch_coredump_calls().

A new set of __spufs_<file>_read/get() functions was provided to allow the
coredump code to read from the spufs files without having to lock the
SPU context for each file read from.

Cc: <linux-arch@vger.kernel.org>
Signed-off-by: Dwayne Grant McConnell <decimal@us.ibm.com>
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>

3 files changed, 30 insertions, 0 deletions

diff --git a/include/asm-powerpc/elf.h b/include/asm-powerpc/elf.h
index 9a83a987d396..4545aa682509 100644
--- a/include/asm-powerpc/elf.h
+++ b/include/asm-powerpc/elf.h
@@ -411,4 +411,17 @@ do {									\
 /* Keep this the last entry.  */
 #define R_PPC64_NUM             107
 
+#ifdef CONFIG_PPC_CELL
+/* Notes used in ET_CORE. Note name is "SPU/<fd>/<filename>". */
+#define NT_SPU          1
+
+extern int arch_notes_size(void);
+extern void arch_write_notes(struct file *file);
+
+#define ELF_CORE_EXTRA_NOTES_SIZE arch_notes_size()
+#define ELF_CORE_WRITE_EXTRA_NOTES arch_write_notes(file)
+
+#define ARCH_HAVE_EXTRA_ELF_NOTES
+#endif /* CONFIG_PPC_CELL */
+
 #endif /* _ASM_POWERPC_ELF_H */
diff --git a/include/asm-powerpc/spu.h b/include/asm-powerpc/spu.h
index ffa4df083609..f968f8697538 100644
--- a/include/asm-powerpc/spu.h
+++ b/include/asm-powerpc/spu.h
@@ -172,6 +172,13 @@ extern struct spufs_calls {
         struct module *owner;
 } spufs_calls;
 
+/* coredump calls implemented in spufs */
+struct spu_coredump_calls {
+        asmlinkage int (*arch_notes_size)(void);
+        asmlinkage void (*arch_write_notes)(struct file *file);
+        struct module *owner;
+};
+
 /* return status from spu_run, same as in libspe */
 #define SPE_EVENT_DMA_ALIGNMENT         0x0008  /*A DMA alignment error */
 #define SPE_EVENT_SPE_ERROR             0x0010  /*An illegal instruction error*/
@@ -203,6 +210,9 @@ static inline void unregister_spu_syscalls(struct spufs_calls *calls)
 }
 #endif /* MODULE */
 
+int register_arch_coredump_calls(struct spu_coredump_calls *calls);
+void unregister_arch_coredump_calls(struct spu_coredump_calls *calls);
+
 int spu_add_sysdev_attr(struct sysdev_attribute *attr);
 void spu_remove_sysdev_attr(struct sysdev_attribute *attr);
 
diff --git a/include/linux/elf.h b/include/linux/elf.h
index b70d1d2c8d28..743d5c8e6d36 100644
--- a/include/linux/elf.h
+++ b/include/linux/elf.h
@@ -368,5 +368,12 @@ extern Elf64_Dyn _DYNAMIC [];
 
 #endif
 
+#ifndef ARCH_HAVE_EXTRA_ELF_NOTES
+static inline int arch_notes_size(void) { return 0; }
+static inline void arch_write_notes(struct file *file) { }
+
+#define ELF_CORE_EXTRA_NOTES_SIZE arch_notes_size()
+#define ELF_CORE_WRITE_EXTRA_NOTES arch_write_notes(file)
+#endif /* ARCH_HAVE_EXTRA_ELF_NOTES */
 
 #endif /* _LINUX_ELF_H */