ps3: Replace direct file operations by callback

Currently the FLASH database is updated by the kernel using file operations,
meant for userspace only. While this works for us because copy_{from,to}_user()
on powerpc can handle kernel pointers, this is unportable and a bad example.
Replace the file operations by callbacks, registered by the ps3flash driver.

Signed-off-by: Geert Uytterhoeven <Geert.Uytterhoeven@sonycom.com>
Cc: Geoff Levand <geoffrey.levand@am.sony.com>
Acked-by: Geoff Levand <geoffrey.levand@am.sony.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
diff --git a/arch/powerpc/include/asm/ps3.h b/arch/powerpc/include/asm/ps3.h
index 7660694..7f065e1 100644
--- a/arch/powerpc/include/asm/ps3.h
+++ b/arch/powerpc/include/asm/ps3.h
@@ -53,6 +53,13 @@
 extern u64 ps3_os_area_get_rtc_diff(void);
 extern void ps3_os_area_set_rtc_diff(u64 rtc_diff);
 
+struct ps3_os_area_flash_ops {
+	ssize_t (*read)(void *buf, size_t count, loff_t pos);
+	ssize_t (*write)(const void *buf, size_t count, loff_t pos);
+};
+
+extern void ps3_os_area_flash_register(const struct ps3_os_area_flash_ops *ops);
+
 /* dma routines */
 
 enum ps3_dma_page_size {