bootmem: clean up arch-specific bootmem wrapping

Impact: cleaner and consistent bootmem wrapping

By setting CONFIG_HAVE_ARCH_BOOTMEM_NODE, archs can define
arch-specific wrappers for bootmem allocation.  However, this is done
a bit strangely in that only the high level convenience macros can be
changed while lower level, but still exported, interface functions
can't be wrapped.  This not only is messy but also leads to strange
situation where alloc_bootmem() does what the arch wants it to do but
the equivalent __alloc_bootmem() call doesn't although they should be
able to be used interchangeably.

This patch updates bootmem such that archs can override / wrap the
backend function - alloc_bootmem_core() instead of the highlevel
interface functions to allow simpler and consistent wrapping.  Also,
HAVE_ARCH_BOOTMEM_NODE is renamed to HAVE_ARCH_BOOTMEM.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Johannes Weiner <hannes@saeurebad.de>

1 files changed, 11 insertions, 3 deletions

diff --git a/mm/bootmem.c b/mm/bootmem.c
index 51a0ccf61e0e..d7140c008ba8 100644
--- a/mm/bootmem.c
+++ b/mm/bootmem.c
@@ -37,6 +37,16 @@ static struct list_head bdata_list __initdata = LIST_HEAD_INIT(bdata_list);
 
 static int bootmem_debug;
 
+/*
+ * If an arch needs to apply workarounds to bootmem allocation, it can
+ * set CONFIG_HAVE_ARCH_BOOTMEM and define a wrapper around
+ * __alloc_bootmem_core().
+ */
+#ifndef CONFIG_HAVE_ARCH_BOOTMEM
+#define alloc_bootmem_core(bdata, size, align, goal, limit)             \
+        __alloc_bootmem_core((bdata), (size), (align), (goal), (limit))
+#endif
+
 static int __init bootmem_debug_setup(char *buf)
 {
         bootmem_debug = 1;
@@ -382,7 +392,6 @@ int __init reserve_bootmem_node(pg_data_t *pgdat, unsigned long physaddr,
         return mark_bootmem_node(pgdat->bdata, start, end, 1, flags);
 }
 
-#ifndef CONFIG_HAVE_ARCH_BOOTMEM_NODE
 /**
  * reserve_bootmem - mark a page range as usable
  * @addr: starting address of the range
@@ -403,7 +412,6 @@ int __init reserve_bootmem(unsigned long addr, unsigned long size,
 
         return mark_bootmem(start, end, 1, flags);
 }
-#endif /* !CONFIG_HAVE_ARCH_BOOTMEM_NODE */
 
 static unsigned long align_idx(struct bootmem_data *bdata, unsigned long idx,
                         unsigned long step)
@@ -428,7 +436,7 @@ static unsigned long align_off(struct bootmem_data *bdata, unsigned long off,
         return ALIGN(base + off, align) - base;
 }
 
-static void * __init alloc_bootmem_core(struct bootmem_data *bdata,
+static void * __init __alloc_bootmem_core(struct bootmem_data *bdata,
                                 unsigned long size, unsigned long align,
                                 unsigned long goal, unsigned long limit)
 {