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authorLinus Torvalds <torvalds@linux-foundation.org>2014-10-09 22:26:14 -0400
committerLinus Torvalds <torvalds@linux-foundation.org>2014-10-09 22:26:14 -0400
commit0cf744bc7ae8e0072159a901f6e1a159bbc30ffa (patch)
treefc8222a3a5af4f42226070c3f76462cfcf0b4e50 /arch/arm
parentb528392669415dc1e53a047215e5ad6c2de879fc (diff)
parent7f8998c7aef3ac9c5f3f2943e083dfa6302e90d0 (diff)
Merge branch 'akpm' (fixes from Andrew Morton)
Merge patch-bomb from Andrew Morton: - part of OCFS2 (review is laggy again) - procfs - slab - all of MM - zram, zbud - various other random things: arch, filesystems. * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (164 commits) nosave: consolidate __nosave_{begin,end} in <asm/sections.h> include/linux/screen_info.h: remove unused ORIG_* macros kernel/sys.c: compat sysinfo syscall: fix undefined behavior kernel/sys.c: whitespace fixes acct: eliminate compile warning kernel/async.c: switch to pr_foo() include/linux/blkdev.h: use NULL instead of zero include/linux/kernel.h: deduplicate code implementing clamp* macros include/linux/kernel.h: rewrite min3, max3 and clamp using min and max alpha: use Kbuild logic to include <asm-generic/sections.h> frv: remove deprecated IRQF_DISABLED frv: remove unused cpuinfo_frv and friends to fix future build error zbud: avoid accessing last unused freelist zsmalloc: simplify init_zspage free obj linking mm/zsmalloc.c: correct comment for fullness group computation zram: use notify_free to account all free notifications zram: report maximum used memory zram: zram memory size limitation zsmalloc: change return value unit of zs_get_total_size_bytes zsmalloc: move pages_allocated to zs_pool ...
Diffstat (limited to 'arch/arm')
-rw-r--r--arch/arm/Kconfig6
-rw-r--r--arch/arm/include/asm/pgtable-2level.h2
-rw-r--r--arch/arm/include/asm/pgtable-3level.h15
-rw-r--r--arch/arm/include/asm/pgtable.h6
-rw-r--r--arch/arm/include/asm/tlb.h38
-rw-r--r--arch/arm/kernel/hibernate.c3
-rw-r--r--arch/arm/mm/dma-mapping.c210
-rw-r--r--arch/arm/mm/flush.c15
-rw-r--r--arch/arm/mm/init.c2
9 files changed, 136 insertions, 161 deletions
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index d9d32de9628c..18f392f8b744 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -14,6 +14,7 @@ config ARM
select CLONE_BACKWARDS
select CPU_PM if (SUSPEND || CPU_IDLE)
select DCACHE_WORD_ACCESS if HAVE_EFFICIENT_UNALIGNED_ACCESS
+ select GENERIC_ALLOCATOR
select GENERIC_ATOMIC64 if (CPU_V7M || CPU_V6 || !CPU_32v6K || !AEABI)
select GENERIC_CLOCKEVENTS_BROADCAST if SMP
select GENERIC_IDLE_POLL_SETUP
@@ -61,6 +62,7 @@ config ARM
select HAVE_PERF_EVENTS
select HAVE_PERF_REGS
select HAVE_PERF_USER_STACK_DUMP
+ select HAVE_RCU_TABLE_FREE if (SMP && ARM_LPAE)
select HAVE_REGS_AND_STACK_ACCESS_API
select HAVE_SYSCALL_TRACEPOINTS
select HAVE_UID16
@@ -1659,6 +1661,10 @@ config ARCH_SELECT_MEMORY_MODEL
config HAVE_ARCH_PFN_VALID
def_bool ARCH_HAS_HOLES_MEMORYMODEL || !SPARSEMEM
+config HAVE_GENERIC_RCU_GUP
+ def_bool y
+ depends on ARM_LPAE
+
config HIGHMEM
bool "High Memory Support"
depends on MMU
diff --git a/arch/arm/include/asm/pgtable-2level.h b/arch/arm/include/asm/pgtable-2level.h
index 219ac88a9542..f0279411847d 100644
--- a/arch/arm/include/asm/pgtable-2level.h
+++ b/arch/arm/include/asm/pgtable-2level.h
@@ -182,6 +182,8 @@ static inline pmd_t *pmd_offset(pud_t *pud, unsigned long addr)
#define pmd_addr_end(addr,end) (end)
#define set_pte_ext(ptep,pte,ext) cpu_set_pte_ext(ptep,pte,ext)
+#define pte_special(pte) (0)
+static inline pte_t pte_mkspecial(pte_t pte) { return pte; }
/*
* We don't have huge page support for short descriptors, for the moment
diff --git a/arch/arm/include/asm/pgtable-3level.h b/arch/arm/include/asm/pgtable-3level.h
index 06e0bc0f8b00..a31ecdad4b59 100644
--- a/arch/arm/include/asm/pgtable-3level.h
+++ b/arch/arm/include/asm/pgtable-3level.h
@@ -213,10 +213,19 @@ static inline pmd_t *pmd_offset(pud_t *pud, unsigned long addr)
#define pmd_isclear(pmd, val) (!(pmd_val(pmd) & (val)))
#define pmd_young(pmd) (pmd_isset((pmd), PMD_SECT_AF))
+#define pte_special(pte) (pte_isset((pte), L_PTE_SPECIAL))
+static inline pte_t pte_mkspecial(pte_t pte)
+{
+ pte_val(pte) |= L_PTE_SPECIAL;
+ return pte;
+}
+#define __HAVE_ARCH_PTE_SPECIAL
#define __HAVE_ARCH_PMD_WRITE
#define pmd_write(pmd) (pmd_isclear((pmd), L_PMD_SECT_RDONLY))
#define pmd_dirty(pmd) (pmd_isset((pmd), L_PMD_SECT_DIRTY))
+#define pud_page(pud) pmd_page(__pmd(pud_val(pud)))
+#define pud_write(pud) pmd_write(__pmd(pud_val(pud)))
#define pmd_hugewillfault(pmd) (!pmd_young(pmd) || !pmd_write(pmd))
#define pmd_thp_or_huge(pmd) (pmd_huge(pmd) || pmd_trans_huge(pmd))
@@ -224,6 +233,12 @@ static inline pmd_t *pmd_offset(pud_t *pud, unsigned long addr)
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
#define pmd_trans_huge(pmd) (pmd_val(pmd) && !pmd_table(pmd))
#define pmd_trans_splitting(pmd) (pmd_isset((pmd), L_PMD_SECT_SPLITTING))
+
+#ifdef CONFIG_HAVE_RCU_TABLE_FREE
+#define __HAVE_ARCH_PMDP_SPLITTING_FLUSH
+void pmdp_splitting_flush(struct vm_area_struct *vma, unsigned long address,
+ pmd_t *pmdp);
+#endif
#endif
#define PMD_BIT_FUNC(fn,op) \
diff --git a/arch/arm/include/asm/pgtable.h b/arch/arm/include/asm/pgtable.h
index 01baef07cd0c..90aa4583b308 100644
--- a/arch/arm/include/asm/pgtable.h
+++ b/arch/arm/include/asm/pgtable.h
@@ -226,7 +226,6 @@ static inline pte_t *pmd_page_vaddr(pmd_t pmd)
#define pte_dirty(pte) (pte_isset((pte), L_PTE_DIRTY))
#define pte_young(pte) (pte_isset((pte), L_PTE_YOUNG))
#define pte_exec(pte) (pte_isclear((pte), L_PTE_XN))
-#define pte_special(pte) (0)
#define pte_valid_user(pte) \
(pte_valid(pte) && pte_isset((pte), L_PTE_USER) && pte_young(pte))
@@ -245,7 +244,8 @@ static inline void set_pte_at(struct mm_struct *mm, unsigned long addr,
unsigned long ext = 0;
if (addr < TASK_SIZE && pte_valid_user(pteval)) {
- __sync_icache_dcache(pteval);
+ if (!pte_special(pteval))
+ __sync_icache_dcache(pteval);
ext |= PTE_EXT_NG;
}
@@ -264,8 +264,6 @@ PTE_BIT_FUNC(mkyoung, |= L_PTE_YOUNG);
PTE_BIT_FUNC(mkexec, &= ~L_PTE_XN);
PTE_BIT_FUNC(mknexec, |= L_PTE_XN);
-static inline pte_t pte_mkspecial(pte_t pte) { return pte; }
-
static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
{
const pteval_t mask = L_PTE_XN | L_PTE_RDONLY | L_PTE_USER |
diff --git a/arch/arm/include/asm/tlb.h b/arch/arm/include/asm/tlb.h
index f1a0dace3efe..3cadb726ec88 100644
--- a/arch/arm/include/asm/tlb.h
+++ b/arch/arm/include/asm/tlb.h
@@ -35,12 +35,39 @@
#define MMU_GATHER_BUNDLE 8
+#ifdef CONFIG_HAVE_RCU_TABLE_FREE
+static inline void __tlb_remove_table(void *_table)
+{
+ free_page_and_swap_cache((struct page *)_table);
+}
+
+struct mmu_table_batch {
+ struct rcu_head rcu;
+ unsigned int nr;
+ void *tables[0];
+};
+
+#define MAX_TABLE_BATCH \
+ ((PAGE_SIZE - sizeof(struct mmu_table_batch)) / sizeof(void *))
+
+extern void tlb_table_flush(struct mmu_gather *tlb);
+extern void tlb_remove_table(struct mmu_gather *tlb, void *table);
+
+#define tlb_remove_entry(tlb, entry) tlb_remove_table(tlb, entry)
+#else
+#define tlb_remove_entry(tlb, entry) tlb_remove_page(tlb, entry)
+#endif /* CONFIG_HAVE_RCU_TABLE_FREE */
+
/*
* TLB handling. This allows us to remove pages from the page
* tables, and efficiently handle the TLB issues.
*/
struct mmu_gather {
struct mm_struct *mm;
+#ifdef CONFIG_HAVE_RCU_TABLE_FREE
+ struct mmu_table_batch *batch;
+ unsigned int need_flush;
+#endif
unsigned int fullmm;
struct vm_area_struct *vma;
unsigned long start, end;
@@ -101,6 +128,9 @@ static inline void __tlb_alloc_page(struct mmu_gather *tlb)
static inline void tlb_flush_mmu_tlbonly(struct mmu_gather *tlb)
{
tlb_flush(tlb);
+#ifdef CONFIG_HAVE_RCU_TABLE_FREE
+ tlb_table_flush(tlb);
+#endif
}
static inline void tlb_flush_mmu_free(struct mmu_gather *tlb)
@@ -129,6 +159,10 @@ tlb_gather_mmu(struct mmu_gather *tlb, struct mm_struct *mm, unsigned long start
tlb->pages = tlb->local;
tlb->nr = 0;
__tlb_alloc_page(tlb);
+
+#ifdef CONFIG_HAVE_RCU_TABLE_FREE
+ tlb->batch = NULL;
+#endif
}
static inline void
@@ -205,7 +239,7 @@ static inline void __pte_free_tlb(struct mmu_gather *tlb, pgtable_t pte,
tlb_add_flush(tlb, addr + SZ_1M);
#endif
- tlb_remove_page(tlb, pte);
+ tlb_remove_entry(tlb, pte);
}
static inline void __pmd_free_tlb(struct mmu_gather *tlb, pmd_t *pmdp,
@@ -213,7 +247,7 @@ static inline void __pmd_free_tlb(struct mmu_gather *tlb, pmd_t *pmdp,
{
#ifdef CONFIG_ARM_LPAE
tlb_add_flush(tlb, addr);
- tlb_remove_page(tlb, virt_to_page(pmdp));
+ tlb_remove_entry(tlb, virt_to_page(pmdp));
#endif
}
diff --git a/arch/arm/kernel/hibernate.c b/arch/arm/kernel/hibernate.c
index bb8b79648643..c4cc50e58c13 100644
--- a/arch/arm/kernel/hibernate.c
+++ b/arch/arm/kernel/hibernate.c
@@ -21,8 +21,7 @@
#include <asm/idmap.h>
#include <asm/suspend.h>
#include <asm/memory.h>
-
-extern const void __nosave_begin, __nosave_end;
+#include <asm/sections.h>
int pfn_is_nosave(unsigned long pfn)
{
diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c
index 7a996aaa061e..c245d903927f 100644
--- a/arch/arm/mm/dma-mapping.c
+++ b/arch/arm/mm/dma-mapping.c
@@ -12,6 +12,7 @@
#include <linux/bootmem.h>
#include <linux/module.h>
#include <linux/mm.h>
+#include <linux/genalloc.h>
#include <linux/gfp.h>
#include <linux/errno.h>
#include <linux/list.h>
@@ -298,57 +299,29 @@ static void *
__dma_alloc_remap(struct page *page, size_t size, gfp_t gfp, pgprot_t prot,
const void *caller)
{
- struct vm_struct *area;
- unsigned long addr;
-
/*
* DMA allocation can be mapped to user space, so lets
* set VM_USERMAP flags too.
*/
- area = get_vm_area_caller(size, VM_ARM_DMA_CONSISTENT | VM_USERMAP,
- caller);
- if (!area)
- return NULL;
- addr = (unsigned long)area->addr;
- area->phys_addr = __pfn_to_phys(page_to_pfn(page));
-
- if (ioremap_page_range(addr, addr + size, area->phys_addr, prot)) {
- vunmap((void *)addr);
- return NULL;
- }
- return (void *)addr;
+ return dma_common_contiguous_remap(page, size,
+ VM_ARM_DMA_CONSISTENT | VM_USERMAP,
+ prot, caller);
}
static void __dma_free_remap(void *cpu_addr, size_t size)
{
- unsigned int flags = VM_ARM_DMA_CONSISTENT | VM_USERMAP;
- struct vm_struct *area = find_vm_area(cpu_addr);
- if (!area || (area->flags & flags) != flags) {
- WARN(1, "trying to free invalid coherent area: %p\n", cpu_addr);
- return;
- }
- unmap_kernel_range((unsigned long)cpu_addr, size);
- vunmap(cpu_addr);
+ dma_common_free_remap(cpu_addr, size,
+ VM_ARM_DMA_CONSISTENT | VM_USERMAP);
}
#define DEFAULT_DMA_COHERENT_POOL_SIZE SZ_256K
+static struct gen_pool *atomic_pool;
-struct dma_pool {
- size_t size;
- spinlock_t lock;
- unsigned long *bitmap;
- unsigned long nr_pages;
- void *vaddr;
- struct page **pages;
-};
-
-static struct dma_pool atomic_pool = {
- .size = DEFAULT_DMA_COHERENT_POOL_SIZE,
-};
+static size_t atomic_pool_size = DEFAULT_DMA_COHERENT_POOL_SIZE;
static int __init early_coherent_pool(char *p)
{
- atomic_pool.size = memparse(p, &p);
+ atomic_pool_size = memparse(p, &p);
return 0;
}
early_param("coherent_pool", early_coherent_pool);
@@ -358,14 +331,14 @@ void __init init_dma_coherent_pool_size(unsigned long size)
/*
* Catch any attempt to set the pool size too late.
*/
- BUG_ON(atomic_pool.vaddr);
+ BUG_ON(atomic_pool);
/*
* Set architecture specific coherent pool size only if
* it has not been changed by kernel command line parameter.
*/
- if (atomic_pool.size == DEFAULT_DMA_COHERENT_POOL_SIZE)
- atomic_pool.size = size;
+ if (atomic_pool_size == DEFAULT_DMA_COHERENT_POOL_SIZE)
+ atomic_pool_size = size;
}
/*
@@ -373,52 +346,44 @@ void __init init_dma_coherent_pool_size(unsigned long size)
*/
static int __init atomic_pool_init(void)
{
- struct dma_pool *pool = &atomic_pool;
pgprot_t prot = pgprot_dmacoherent(PAGE_KERNEL);
gfp_t gfp = GFP_KERNEL | GFP_DMA;
- unsigned long nr_pages = pool->size >> PAGE_SHIFT;
- unsigned long *bitmap;
struct page *page;
- struct page **pages;
void *ptr;
- int bitmap_size = BITS_TO_LONGS(nr_pages) * sizeof(long);
- bitmap = kzalloc(bitmap_size, GFP_KERNEL);
- if (!bitmap)
- goto no_bitmap;
-
- pages = kzalloc(nr_pages * sizeof(struct page *), GFP_KERNEL);
- if (!pages)
- goto no_pages;
+ atomic_pool = gen_pool_create(PAGE_SHIFT, -1);
+ if (!atomic_pool)
+ goto out;
if (dev_get_cma_area(NULL))
- ptr = __alloc_from_contiguous(NULL, pool->size, prot, &page,
- atomic_pool_init);
+ ptr = __alloc_from_contiguous(NULL, atomic_pool_size, prot,
+ &page, atomic_pool_init);
else
- ptr = __alloc_remap_buffer(NULL, pool->size, gfp, prot, &page,
- atomic_pool_init);
+ ptr = __alloc_remap_buffer(NULL, atomic_pool_size, gfp, prot,
+ &page, atomic_pool_init);
if (ptr) {
- int i;
-
- for (i = 0; i < nr_pages; i++)
- pages[i] = page + i;
-
- spin_lock_init(&pool->lock);
- pool->vaddr = ptr;
- pool->pages = pages;
- pool->bitmap = bitmap;
- pool->nr_pages = nr_pages;
- pr_info("DMA: preallocated %u KiB pool for atomic coherent allocations\n",
- (unsigned)pool->size / 1024);
+ int ret;
+
+ ret = gen_pool_add_virt(atomic_pool, (unsigned long)ptr,
+ page_to_phys(page),
+ atomic_pool_size, -1);
+ if (ret)
+ goto destroy_genpool;
+
+ gen_pool_set_algo(atomic_pool,
+ gen_pool_first_fit_order_align,
+ (void *)PAGE_SHIFT);
+ pr_info("DMA: preallocated %zd KiB pool for atomic coherent allocations\n",
+ atomic_pool_size / 1024);
return 0;
}
- kfree(pages);
-no_pages:
- kfree(bitmap);
-no_bitmap:
- pr_err("DMA: failed to allocate %u KiB pool for atomic coherent allocation\n",
- (unsigned)pool->size / 1024);
+destroy_genpool:
+ gen_pool_destroy(atomic_pool);
+ atomic_pool = NULL;
+out:
+ pr_err("DMA: failed to allocate %zx KiB pool for atomic coherent allocation\n",
+ atomic_pool_size / 1024);
return -ENOMEM;
}
/*
@@ -522,76 +487,36 @@ static void *__alloc_remap_buffer(struct device *dev, size_t size, gfp_t gfp,
static void *__alloc_from_pool(size_t size, struct page **ret_page)
{
- struct dma_pool *pool = &atomic_pool;
- unsigned int count = PAGE_ALIGN(size) >> PAGE_SHIFT;
- unsigned int pageno;
- unsigned long flags;
+ unsigned long val;
void *ptr = NULL;
- unsigned long align_mask;
- if (!pool->vaddr) {
+ if (!atomic_pool) {
WARN(1, "coherent pool not initialised!\n");
return NULL;
}
- /*
- * Align the region allocation - allocations from pool are rather
- * small, so align them to their order in pages, minimum is a page
- * size. This helps reduce fragmentation of the DMA space.
- */
- align_mask = (1 << get_order(size)) - 1;
-
- spin_lock_irqsave(&pool->lock, flags);
- pageno = bitmap_find_next_zero_area(pool->bitmap, pool->nr_pages,
- 0, count, align_mask);
- if (pageno < pool->nr_pages) {
- bitmap_set(pool->bitmap, pageno, count);
- ptr = pool->vaddr + PAGE_SIZE * pageno;
- *ret_page = pool->pages[pageno];
- } else {
- pr_err_once("ERROR: %u KiB atomic DMA coherent pool is too small!\n"
- "Please increase it with coherent_pool= kernel parameter!\n",
- (unsigned)pool->size / 1024);
+ val = gen_pool_alloc(atomic_pool, size);
+ if (val) {
+ phys_addr_t phys = gen_pool_virt_to_phys(atomic_pool, val);
+
+ *ret_page = phys_to_page(phys);
+ ptr = (void *)val;
}
- spin_unlock_irqrestore(&pool->lock, flags);
return ptr;
}
static bool __in_atomic_pool(void *start, size_t size)
{
- struct dma_pool *pool = &atomic_pool;
- void *end = start + size;
- void *pool_start = pool->vaddr;
- void *pool_end = pool->vaddr + pool->size;
-
- if (start < pool_start || start >= pool_end)
- return false;
-
- if (end <= pool_end)
- return true;
-
- WARN(1, "Wrong coherent size(%p-%p) from atomic pool(%p-%p)\n",
- start, end - 1, pool_start, pool_end - 1);
-
- return false;
+ return addr_in_gen_pool(atomic_pool, (unsigned long)start, size);
}
static int __free_from_pool(void *start, size_t size)
{
- struct dma_pool *pool = &atomic_pool;
- unsigned long pageno, count;
- unsigned long flags;
-
if (!__in_atomic_pool(start, size))
return 0;
- pageno = (start - pool->vaddr) >> PAGE_SHIFT;
- count = size >> PAGE_SHIFT;
-
- spin_lock_irqsave(&pool->lock, flags);
- bitmap_clear(pool->bitmap, pageno, count);
- spin_unlock_irqrestore(&pool->lock, flags);
+ gen_pool_free(atomic_pool, (unsigned long)start, size);
return 1;
}
@@ -1271,29 +1196,8 @@ static void *
__iommu_alloc_remap(struct page **pages, size_t size, gfp_t gfp, pgprot_t prot,
const void *caller)
{
- unsigned int i, nr_pages = PAGE_ALIGN(size) >> PAGE_SHIFT;
- struct vm_struct *area;
- unsigned long p;
-
- area = get_vm_area_caller(size, VM_ARM_DMA_CONSISTENT | VM_USERMAP,
- caller);
- if (!area)
- return NULL;
-
- area->pages = pages;
- area->nr_pages = nr_pages;
- p = (unsigned long)area->addr;
-
- for (i = 0; i < nr_pages; i++) {
- phys_addr_t phys = __pfn_to_phys(page_to_pfn(pages[i]));
- if (ioremap_page_range(p, p + PAGE_SIZE, phys, prot))
- goto err;
- p += PAGE_SIZE;
- }
- return area->addr;
-err:
- unmap_kernel_range((unsigned long)area->addr, size);
- vunmap(area->addr);
+ return dma_common_pages_remap(pages, size,
+ VM_ARM_DMA_CONSISTENT | VM_USERMAP, prot, caller);
return NULL;
}
@@ -1355,11 +1259,13 @@ static int __iommu_remove_mapping(struct device *dev, dma_addr_t iova, size_t si
static struct page **__atomic_get_pages(void *addr)
{
- struct dma_pool *pool = &atomic_pool;
- struct page **pages = pool->pages;
- int offs = (addr - pool->vaddr) >> PAGE_SHIFT;
+ struct page *page;
+ phys_addr_t phys;
+
+ phys = gen_pool_virt_to_phys(atomic_pool, (unsigned long)addr);
+ page = phys_to_page(phys);
- return pages + offs;
+ return (struct page **)page;
}
static struct page **__iommu_get_pages(void *cpu_addr, struct dma_attrs *attrs)
@@ -1501,8 +1407,8 @@ void arm_iommu_free_attrs(struct device *dev, size_t size, void *cpu_addr,
}
if (!dma_get_attr(DMA_ATTR_NO_KERNEL_MAPPING, attrs)) {
- unmap_kernel_range((unsigned long)cpu_addr, size);
- vunmap(cpu_addr);
+ dma_common_free_remap(cpu_addr, size,
+ VM_ARM_DMA_CONSISTENT | VM_USERMAP);
}
__iommu_remove_mapping(dev, handle, size);
diff --git a/arch/arm/mm/flush.c b/arch/arm/mm/flush.c
index 43d54f5b26b9..265b836b3bd1 100644
--- a/arch/arm/mm/flush.c
+++ b/arch/arm/mm/flush.c
@@ -400,3 +400,18 @@ void __flush_anon_page(struct vm_area_struct *vma, struct page *page, unsigned l
*/
__cpuc_flush_dcache_area(page_address(page), PAGE_SIZE);
}
+
+#ifdef CONFIG_TRANSPARENT_HUGEPAGE
+#ifdef CONFIG_HAVE_RCU_TABLE_FREE
+void pmdp_splitting_flush(struct vm_area_struct *vma, unsigned long address,
+ pmd_t *pmdp)
+{
+ pmd_t pmd = pmd_mksplitting(*pmdp);
+ VM_BUG_ON(address & ~PMD_MASK);
+ set_pmd_at(vma->vm_mm, address, pmdp, pmd);
+
+ /* dummy IPI to serialise against fast_gup */
+ kick_all_cpus_sync();
+}
+#endif /* CONFIG_HAVE_RCU_TABLE_FREE */
+#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
diff --git a/arch/arm/mm/init.c b/arch/arm/mm/init.c
index 9221645dd192..92bba32d9230 100644
--- a/arch/arm/mm/init.c
+++ b/arch/arm/mm/init.c
@@ -322,7 +322,7 @@ void __init arm_memblock_init(const struct machine_desc *mdesc)
* reserve memory for DMA contigouos allocations,
* must come from DMA area inside low memory
*/
- dma_contiguous_reserve(min(arm_dma_limit, arm_lowmem_limit));
+ dma_contiguous_reserve(arm_dma_limit);
arm_memblock_steal_permitted = false;
memblock_dump_all();