[POWERPC] pseries: phyp dump: Reserve and release memory
Initial patch for reserving memory in early boot, and freeing it
later. If the previous boot had ended with a crash, the reserved
memory would contain a copy of the crashed kernel data.
Signed-off-by: Manish Ahuja <mahuja@us.ibm.com>
Signed-off-by: Linas Vepstas <linasvepstas@gmail.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
diff --git a/arch/powerpc/kernel/prom.c b/arch/powerpc/kernel/prom.c
index ff600ef..e6c022e 100644
--- a/arch/powerpc/kernel/prom.c
+++ b/arch/powerpc/kernel/prom.c
@@ -51,6 +51,7 @@
#include <asm/machdep.h>
#include <asm/pSeries_reconfig.h>
#include <asm/pci-bridge.h>
+#include <asm/phyp_dump.h>
#include <asm/kexec.h>
#ifdef DEBUG
@@ -1040,6 +1041,51 @@
#endif
}
+#ifdef CONFIG_PHYP_DUMP
+/**
+ * phyp_dump_reserve_mem() - reserve all not-yet-dumped mmemory
+ *
+ * This routine may reserve memory regions in the kernel only
+ * if the system is supported and a dump was taken in last
+ * boot instance or if the hardware is supported and the
+ * scratch area needs to be setup. In other instances it returns
+ * without reserving anything. The memory in case of dump being
+ * active is freed when the dump is collected (by userland tools).
+ */
+static void __init phyp_dump_reserve_mem(void)
+{
+ unsigned long base, size;
+ if (!phyp_dump_info->phyp_dump_configured) {
+ printk(KERN_ERR "Phyp-dump not supported on this hardware\n");
+ return;
+ }
+
+ if (phyp_dump_info->phyp_dump_is_active) {
+ /* Reserve *everything* above RMR.Area freed by userland tools*/
+ base = PHYP_DUMP_RMR_END;
+ size = lmb_end_of_DRAM() - base;
+
+ /* XXX crashed_ram_end is wrong, since it may be beyond
+ * the memory_limit, it will need to be adjusted. */
+ lmb_reserve(base, size);
+
+ phyp_dump_info->init_reserve_start = base;
+ phyp_dump_info->init_reserve_size = size;
+ } else {
+ size = phyp_dump_info->cpu_state_size +
+ phyp_dump_info->hpte_region_size +
+ PHYP_DUMP_RMR_END;
+ base = lmb_end_of_DRAM() - size;
+ lmb_reserve(base, size);
+ phyp_dump_info->init_reserve_start = base;
+ phyp_dump_info->init_reserve_size = size;
+ }
+}
+#else
+static inline void __init phyp_dump_reserve_mem(void) {}
+#endif /* CONFIG_PHYP_DUMP && CONFIG_PPC_RTAS */
+
+
void __init early_init_devtree(void *params)
{
DBG(" -> early_init_devtree(%p)\n", params);
@@ -1052,6 +1098,11 @@
of_scan_flat_dt(early_init_dt_scan_rtas, NULL);
#endif
+#ifdef CONFIG_PHYP_DUMP
+ /* scan tree to see if dump occured during last boot */
+ of_scan_flat_dt(early_init_dt_scan_phyp_dump, NULL);
+#endif
+
/* Retrieve various informations from the /chosen node of the
* device-tree, including the platform type, initrd location and
* size, TCE reserve, and more ...
@@ -1072,6 +1123,7 @@
reserve_kdump_trampoline();
reserve_crashkernel();
early_reserve_mem();
+ phyp_dump_reserve_mem();
lmb_enforce_memory_limit(memory_limit);
lmb_analyze();
