Introduce flags for reserve_bootmem()

This patchset adds a flags variable to reserve_bootmem() and uses the
BOOTMEM_EXCLUSIVE flag in crashkernel reservation code to detect collisions
between crashkernel area and already used memory.

This patch:

Change the reserve_bootmem() function to accept a new flag BOOTMEM_EXCLUSIVE.
If that flag is set, the function returns with -EBUSY if the memory already
has been reserved in the past.  This is to avoid conflicts.

Because that code runs before SMP initialisation, there's no race condition
inside reserve_bootmem_core().

[akpm@linux-foundation.org: coding-style fixes]
[akpm@linux-foundation.org: fix powerpc build]
Signed-off-by: Bernhard Walle <bwalle@suse.de>
Cc: <linux-arch@vger.kernel.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Vivek Goyal <vgoyal@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 4 insertions, 4 deletions

diff --git a/arch/sparc64/mm/init.c b/arch/sparc64/mm/init.c
index 523e993ee90c..e726c45645ff 100644
--- a/arch/sparc64/mm/init.c
+++ b/arch/sparc64/mm/init.c
@@ -997,7 +997,7 @@ static unsigned long __init bootmem_init(unsigned long *pages_avail,
                 prom_printf("reserve_bootmem(initrd): base[%llx] size[%lx]\n",
                         initrd_start, initrd_end);
 #endif
-                reserve_bootmem(initrd_start, size);
+                reserve_bootmem(initrd_start, size, BOOTMEM_DEFAULT);
 
                 initrd_start += PAGE_OFFSET;
                 initrd_end += PAGE_OFFSET;
@@ -1007,7 +1007,7 @@ static unsigned long __init bootmem_init(unsigned long *pages_avail,
 #ifdef CONFIG_DEBUG_BOOTMEM
         prom_printf("reserve_bootmem(kernel): base[%lx] size[%lx]\n", kern_base, kern_size);
 #endif
-        reserve_bootmem(kern_base, kern_size);
+        reserve_bootmem(kern_base, kern_size, BOOTMEM_DEFAULT);
         *pages_avail -= PAGE_ALIGN(kern_size) >> PAGE_SHIFT;
 
         /* Add back in the initmem pages. */
@@ -1024,7 +1024,7 @@ static unsigned long __init bootmem_init(unsigned long *pages_avail,
         prom_printf("reserve_bootmem(bootmap): base[%lx] size[%lx]\n",
                     (bootmap_pfn << PAGE_SHIFT), size);
 #endif
-        reserve_bootmem((bootmap_pfn << PAGE_SHIFT), size);
+        reserve_bootmem((bootmap_pfn << PAGE_SHIFT), size, BOOTMEM_DEFAULT);
 
         for (i = 0; i < pavail_ents; i++) {
                 unsigned long start_pfn, end_pfn;
@@ -1489,7 +1489,7 @@ static void __init taint_real_pages(void)
                                         goto do_next_page;
                                 }
                         }
-                        reserve_bootmem(old_start, PAGE_SIZE);
+                        reserve_bootmem(old_start, PAGE_SIZE, BOOTMEM_DEFAULT);
 
                 do_next_page:
                         old_start += PAGE_SIZE;