Merge branch 'akpm'

* akpm: (173 commits)
  genalloc: use bitmap_find_next_zero_area
  ia64: use bitmap_find_next_zero_area
  sparc: use bitmap_find_next_zero_area
  mlx4: use bitmap_find_next_zero_area
  isp1362-hcd: use bitmap_find_next_zero_area
  iommu-helper: use bitmap library
  bitmap: introduce bitmap_set, bitmap_clear, bitmap_find_next_zero_area
  qnx4: use hweight8
  qnx4fs: remove remains of the (defunct) write support
  resource: constify arg to resource_size() and resource_type()
  gru: send cross partition interrupts using the gru
  gru: function to generate chipset IPI values
  gru: update driver version number
  gru: improve GRU TLB dropin statistics
  gru: fix GRU interrupt race at deallocate
  gru: add hugepage support
  gru: fix bug in allocation of kernel contexts
  gru: update GRU structures to match latest hardware spec
  gru: check for correct GRU chiplet assignment
  gru: remove stray local_irq_enable
  ...

1 files changed, 59 insertions, 0 deletions

diff --git a/kernel/kexec.c b/kernel/kexec.c
index f336e2107f98..433e9fcc1fc5 100644
--- 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)
 {