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, 3 insertions, 3 deletions

diff --git a/arch/sparc/mm/init.c b/arch/sparc/mm/init.c
index a1bef07755a9..b89837accc88 100644
--- a/arch/sparc/mm/init.c
+++ b/arch/sparc/mm/init.c
@@ -259,7 +259,7 @@ unsigned long __init bootmem_init(unsigned long *pages_avail)
         if (initrd_start) {
                 /* Reserve the initrd image area. */
                 size = initrd_end - initrd_start;
-                reserve_bootmem(initrd_start, size);
+                reserve_bootmem(initrd_start, size, BOOTMEM_DEFAULT);
                 *pages_avail -= PAGE_ALIGN(size) >> PAGE_SHIFT;
 
                 initrd_start = (initrd_start - phys_base) + PAGE_OFFSET;
@@ -268,7 +268,7 @@ unsigned long __init bootmem_init(unsigned long *pages_avail)
 #endif
         /* Reserve the kernel text/data/bss. */
         size = (start_pfn << PAGE_SHIFT) - phys_base;
-        reserve_bootmem(phys_base, size);
+        reserve_bootmem(phys_base, size, BOOTMEM_DEFAULT);
         *pages_avail -= PAGE_ALIGN(size) >> PAGE_SHIFT;
 
         /* Reserve the bootmem map.   We do not account for it
@@ -276,7 +276,7 @@ unsigned long __init bootmem_init(unsigned long *pages_avail)
          * in free_all_bootmem.
          */
         size = bootmap_size;
-        reserve_bootmem((bootmap_pfn << PAGE_SHIFT), size);
+        reserve_bootmem((bootmap_pfn << PAGE_SHIFT), size, BOOTMEM_DEFAULT);
         *pages_avail -= PAGE_ALIGN(size) >> PAGE_SHIFT;
 
         return max_pfn;