Merge branch 'for-33' of git://repo.or.cz/linux-kbuild

[sfrench/cifs-2.6.git] / kernel / kexec.c

diff --git a/kernel/kexec.c b/kernel/kexec.c
index 83f54e2a6eedea011f0ecfc5c2da06d1dbef6226..a9a93d9ee7a78e70068bca678826873376afd8a7 100644 (file)
--- a/kernel/kexec.c
+++ b/kernel/kexec.c
@@ -31,6 +31,7 @@
 #include <linux/cpu.h>
 #include <linux/console.h>
 #include <linux/vmalloc.h>
+#include <linux/swap.h>
 
 #include <asm/page.h>
 #include <asm/uaccess.h>
@@ -1082,6 +1083,64 @@ void crash_kexec(struct pt_regs *regs)
        }
 }
 
+size_t crash_get_memory_size(void)
+{
+       size_t size;
+       mutex_lock(&kexec_mutex);
+       size = crashk_res.end - crashk_res.start + 1;
+       mutex_unlock(&kexec_mutex);
+       return size;
+}
+
+static void free_reserved_phys_range(unsigned long begin, unsigned long end)
+{
+       unsigned long addr;
+
+       for (addr = begin; addr < end; addr += PAGE_SIZE) {
+               ClearPageReserved(pfn_to_page(addr >> PAGE_SHIFT));
+               init_page_count(pfn_to_page(addr >> PAGE_SHIFT));
+               free_page((unsigned long)__va(addr));
+               totalram_pages++;
+       }
+}
+
+int crash_shrink_memory(unsigned long new_size)
+{
+       int ret = 0;
+       unsigned long start, end;
+
+       mutex_lock(&kexec_mutex);
+
+       if (kexec_crash_image) {
+               ret = -ENOENT;
+               goto unlock;
+       }
+       start = crashk_res.start;
+       end = crashk_res.end;
+
+       if (new_size >= end - start + 1) {
+               ret = -EINVAL;
+               if (new_size == end - start + 1)
+                       ret = 0;
+               goto unlock;
+       }
+
+       start = roundup(start, PAGE_SIZE);
+       end = roundup(start + new_size, PAGE_SIZE);
+
+       free_reserved_phys_range(end, crashk_res.end);
+
+       if (start == end) {
+               crashk_res.end = end;
+               release_resource(&crashk_res);
+       } else
+               crashk_res.end = end - 1;
+
+unlock:
+       mutex_unlock(&kexec_mutex);
+       return ret;
+}
+
 static u32 *append_elf_note(u32 *buf, char *name, unsigned type, void *data,
                            size_t data_len)
 {