memblock: Introduce default allocation limit and use it to replace explicit ones
This introduce memblock.current_limit which is used to limit allocations
from memblock_alloc() or memblock_alloc_base(..., MEMBLOCK_ALLOC_ACCESSIBLE).
The old MEMBLOCK_ALLOC_ANYWHERE changes value from 0 to ~(u64)0 and can still
be used with memblock_alloc_base() to allocate really anywhere.
It is -no-longer- cropped to MEMBLOCK_REAL_LIMIT which disappears.
Note to archs: I'm leaving the default limit to MEMBLOCK_ALLOC_ANYWHERE. I
strongly recommend that you ensure that you set an appropriate limit
during boot in order to guarantee that an memblock_alloc() at any time
results in something that is accessible with a simple __va().
The reason is that a subsequent patch will introduce the ability for
the array to resize itself by reallocating itself. The MEMBLOCK core will
honor the current limit when performing those allocations.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
diff --git a/arch/powerpc/kernel/setup_32.c b/arch/powerpc/kernel/setup_32.c
index a10ffc8..b7eb1de 100644
--- a/arch/powerpc/kernel/setup_32.c
+++ b/arch/powerpc/kernel/setup_32.c
@@ -246,7 +246,7 @@
unsigned int i;
/* interrupt stacks must be in lowmem, we get that for free on ppc32
- * as the memblock is limited to lowmem by MEMBLOCK_REAL_LIMIT */
+ * as the memblock is limited to lowmem by default */
for_each_possible_cpu(i) {
softirq_ctx[i] = (struct thread_info *)
__va(memblock_alloc(THREAD_SIZE, THREAD_SIZE));