ARM: Add arm_memblock_steal() to allocate memory away from the kernel
Several platforms are now using the memblock_alloc+memblock_free+
memblock_remove trick to obtain memory which won't be mapped in the
kernel's page tables. Most platforms do this (correctly) in the
->reserve callback. However, OMAP has started to call these functions
outside of this callback, and this is extremely unsafe - memory will
not be unmapped, and could well be given out after memblock is no
longer responsible for its management.
So, provide arm_memblock_steal() to perform this function, and ensure
that it panic()s if it is used inappropriately. Convert everyone
over, including OMAP.
As a result, OMAP with OMAP4_ERRATA_I688 enabled will panic on boot
with this change. Mark this option as BROKEN and make it depend on
BROKEN. OMAP needs to be fixed, or 137d105d50 (ARM: OMAP4: Fix
errata i688 with MPU interconnect barriers.) reverted until such
time it can be fixed correctly.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
diff --git a/arch/arm/mach-omap2/Kconfig b/arch/arm/mach-omap2/Kconfig
index 904bd1d..a8ba7b9 100644
--- a/arch/arm/mach-omap2/Kconfig
+++ b/arch/arm/mach-omap2/Kconfig
@@ -366,8 +366,8 @@
going on could result in system crashes;
config OMAP4_ERRATA_I688
- bool "OMAP4 errata: Async Bridge Corruption"
- depends on ARCH_OMAP4
+ bool "OMAP4 errata: Async Bridge Corruption (BROKEN)"
+ depends on ARCH_OMAP4 && BROKEN
select ARCH_HAS_BARRIERS
help
If a data is stalled inside asynchronous bridge because of back
diff --git a/arch/arm/mach-omap2/omap-secure.c b/arch/arm/mach-omap2/omap-secure.c
index 69f3c72..d8f8ef4 100644
--- a/arch/arm/mach-omap2/omap-secure.c
+++ b/arch/arm/mach-omap2/omap-secure.c
@@ -16,6 +16,7 @@
#include <linux/memblock.h>
#include <asm/cacheflush.h>
+#include <asm/memblock.h>
#include <mach/omap-secure.h>
@@ -57,20 +58,10 @@
/* Allocate the memory to save secure ram */
int __init omap_secure_ram_reserve_memblock(void)
{
- phys_addr_t paddr;
u32 size = OMAP_SECURE_RAM_STORAGE;
size = ALIGN(size, SZ_1M);
- paddr = memblock_alloc(size, SZ_1M);
- if (!paddr) {
- pr_err("%s: failed to reserve %x bytes\n",
- __func__, size);
- return -ENOMEM;
- }
- memblock_free(paddr, size);
- memblock_remove(paddr, size);
-
- omap_secure_memblock_base = paddr;
+ omap_secure_memblock_base = arm_memblock_steal(size, SZ_1M);
return 0;
}
diff --git a/arch/arm/mach-omap2/omap4-common.c b/arch/arm/mach-omap2/omap4-common.c
index bc16c81..40a8fbc 100644
--- a/arch/arm/mach-omap2/omap4-common.c
+++ b/arch/arm/mach-omap2/omap4-common.c
@@ -20,6 +20,7 @@
#include <asm/hardware/gic.h>
#include <asm/hardware/cache-l2x0.h>
#include <asm/mach/map.h>
+#include <asm/memblock.h>
#include <plat/irqs.h>
#include <plat/sram.h>
@@ -61,13 +62,8 @@
return -ENODEV;
size = ALIGN(PAGE_SIZE, SZ_1M);
- paddr = memblock_alloc(size, SZ_1M);
- if (!paddr) {
- pr_err("%s: failed to reserve 4 Kbytes\n", __func__);
- return -ENOMEM;
- }
- memblock_free(paddr, size);
- memblock_remove(paddr, size);
+ paddr = arm_memblock_steal(size, SZ_1M);
+
dram_io_desc[0].virtual = OMAP4_DRAM_BARRIER_VA;
dram_io_desc[0].pfn = __phys_to_pfn(paddr);
dram_io_desc[0].length = size;