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, 9 insertions, 5 deletions

diff --git a/arch/parisc/mm/init.c b/arch/parisc/mm/init.c
index aa875fa43488..eb80f5e33d7d 100644
--- a/arch/parisc/mm/init.c
+++ b/arch/parisc/mm/init.c
@@ -315,11 +315,13 @@ static void __init setup_bootmem(void)
 #define PDC_CONSOLE_IO_IODC_SIZE 32768
 
         reserve_bootmem_node(NODE_DATA(0), 0UL,
-                        (unsigned long)(PAGE0->mem_free + PDC_CONSOLE_IO_IODC_SIZE));
+                        (unsigned long)(PAGE0->mem_free +
+                                PDC_CONSOLE_IO_IODC_SIZE), BOOTMEM_DEFAULT);
         reserve_bootmem_node(NODE_DATA(0), __pa((unsigned long)_text),
-                        (unsigned long)(_end - _text));
+                        (unsigned long)(_end - _text), BOOTMEM_DEFAULT);
         reserve_bootmem_node(NODE_DATA(0), (bootmap_start_pfn << PAGE_SHIFT),
-                        ((bootmap_pfn - bootmap_start_pfn) << PAGE_SHIFT));
+                        ((bootmap_pfn - bootmap_start_pfn) << PAGE_SHIFT),
+                        BOOTMEM_DEFAULT);
 
 #ifndef CONFIG_DISCONTIGMEM
 
@@ -328,7 +330,8 @@ static void __init setup_bootmem(void)
         for (i = 0; i < npmem_holes; i++) {
                 reserve_bootmem_node(NODE_DATA(0),
                                 (pmem_holes[i].start_pfn << PAGE_SHIFT),
-                                (pmem_holes[i].pages << PAGE_SHIFT));
+                                (pmem_holes[i].pages << PAGE_SHIFT),
+                                BOOTMEM_DEFAULT);
         }
 #endif
 
@@ -346,7 +349,8 @@ static void __init setup_bootmem(void)
                         initrd_below_start_ok = 1;
                         printk(KERN_INFO "initrd: reserving %08lx-%08lx (mem_max %08lx)\n", __pa(initrd_start), __pa(initrd_start) + initrd_reserve, mem_max);
 
-                        reserve_bootmem_node(NODE_DATA(0),__pa(initrd_start), initrd_reserve);
+                        reserve_bootmem_node(NODE_DATA(0), __pa(initrd_start),
+                                        initrd_reserve, BOOTMEM_DEFAULT);
                 }
         }
 #endif