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Merge branch 'for-linus' of git://git.linaro.org/people/mszyprowski/linux-dma-mapping

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Pull CMA and ARM DMA-mapping updates from Marek Szyprowski:
 "These patches contain two major updates for DMA mapping subsystem
  (mainly for ARM architecture).  First one is Contiguous Memory
  Allocator (CMA) which makes it possible for device drivers to allocate
  big contiguous chunks of memory after the system has booted.

  The main difference from the similar frameworks is the fact that CMA
  allows to transparently reuse the memory region reserved for the big
  chunk allocation as a system memory, so no memory is wasted when no
  big chunk is allocated.  Once the alloc request is issued, the
  framework migrates system pages to create space for the required big
  chunk of physically contiguous memory.

  For more information one can refer to nice LWN articles:

   - 'A reworked contiguous memory allocator':
		http://lwn.net/Articles/447405/

   - 'CMA and ARM':
		http://lwn.net/Articles/450286/

   - 'A deep dive into CMA':
		http://lwn.net/Articles/486301/

   - and the following thread with the patches and links to all previous
     versions:
		https://lkml.org/lkml/2012/4/3/204

  The main client for this new framework is ARM DMA-mapping subsystem.

  The second part provides a complete redesign in ARM DMA-mapping
  subsystem.  The core implementation has been changed to use common
  struct dma_map_ops based infrastructure with the recent updates for
  new dma attributes merged in v3.4-rc2.  This allows to use more than
  one implementation of dma-mapping calls and change/select them on the
  struct device basis.  The first client of this new infractructure is
  dmabounce implementation which has been completely cut out of the
  core, common code.

  The last patch of this redesign update introduces a new, experimental
  implementation of dma-mapping calls on top of generic IOMMU framework.
  This lets ARM sub-platform to transparently use IOMMU for DMA-mapping
  calls if one provides required IOMMU hardware.

  For more information please refer to the following thread:
		http://www.spinics.net/lists/arm-kernel/msg175729.html

  The last patch merges changes from both updates and provides a
  resolution for the conflicts which cannot be avoided when patches have
  been applied on the same files (mainly arch/arm/mm/dma-mapping.c)."

Acked by Andrew Morton <akpm@linux-foundation.org>:
 "Yup, this one please.  It's had much work, plenty of review and I
  think even Russell is happy with it."

* 'for-linus' of git://git.linaro.org/people/mszyprowski/linux-dma-mapping: (28 commits)
  ARM: dma-mapping: use PMD size for section unmap
  cma: fix migration mode
  ARM: integrate CMA with DMA-mapping subsystem
  X86: integrate CMA with DMA-mapping subsystem
  drivers: add Contiguous Memory Allocator
  mm: trigger page reclaim in alloc_contig_range() to stabilise watermarks
  mm: extract reclaim code from __alloc_pages_direct_reclaim()
  mm: Serialize access to min_free_kbytes
  mm: page_isolation: MIGRATE_CMA isolation functions added
  mm: mmzone: MIGRATE_CMA migration type added
  mm: page_alloc: change fallbacks array handling
  mm: page_alloc: introduce alloc_contig_range()
  mm: compaction: export some of the functions
  mm: compaction: introduce isolate_freepages_range()
  mm: compaction: introduce map_pages()
  mm: compaction: introduce isolate_migratepages_range()
  mm: page_alloc: remove trailing whitespace
  ARM: dma-mapping: add support for IOMMU mapper
  ARM: dma-mapping: use alloc, mmap, free from dma_ops
  ARM: dma-mapping: remove redundant code and do the cleanup
  ...

Conflicts:
	arch/x86/include/asm/dma-mapping.h
This commit is contained in:
Linus Torvalds 2012-05-25 09:18:59 -07:00
commit d484864dd9
41 changed files with 2899 additions and 781 deletions
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9
Documentation/kernel-parameters.txt
View file

@ -508,6 +508,11 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
Also note the kernel might malfunction if you disable
some critical bits.
cma=nn[MG] [ARM,KNL]
Sets the size of kernel global memory area for contiguous
memory allocations. For more information, see
include/linux/dma-contiguous.h
cmo_free_hint= [PPC] Format: { yes | no }
Specify whether pages are marked as being inactive
when they are freed. This is used in CMO environments
@ -515,6 +520,10 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
a hypervisor.
Default: yes
coherent_pool=nn[KMG] [ARM,KNL]
Sets the size of memory pool for coherent, atomic dma
allocations if Contiguous Memory Allocator (CMA) is used.
code_bytes [X86] How many bytes of object code to print
in an oops report.
Range: 0 - 8192

3
arch/Kconfig
View file

@ -159,6 +159,9 @@ config HAVE_ARCH_TRACEHOOK
config HAVE_DMA_ATTRS
bool
config HAVE_DMA_CONTIGUOUS
bool
config USE_GENERIC_SMP_HELPERS
bool

11
arch/arm/Kconfig
View file

@ -5,6 +5,9 @@ config ARM
select HAVE_AOUT
select HAVE_DMA_API_DEBUG
select HAVE_IDE if PCI || ISA || PCMCIA
select HAVE_DMA_ATTRS
select HAVE_DMA_CONTIGUOUS if (CPU_V6 || CPU_V6K || CPU_V7)
select CMA if (CPU_V6 || CPU_V6K || CPU_V7)
select HAVE_MEMBLOCK
select RTC_LIB
select SYS_SUPPORTS_APM_EMULATION
@ -54,6 +57,14 @@ config ARM
config ARM_HAS_SG_CHAIN
bool
config NEED_SG_DMA_LENGTH
bool
config ARM_DMA_USE_IOMMU
select NEED_SG_DMA_LENGTH
select ARM_HAS_SG_CHAIN
bool
config HAVE_PWM
bool

84
arch/arm/common/dmabounce.c
View file

@ -173,7 +173,8 @@ find_safe_buffer(struct dmabounce_device_info *device_info, dma_addr_t safe_dma_
read_lock_irqsave(&device_info->lock, flags);
list_for_each_entry(b, &device_info->safe_buffers, node)
if (b->safe_dma_addr == safe_dma_addr) {
if (b->safe_dma_addr <= safe_dma_addr &&
b->safe_dma_addr + b->size > safe_dma_addr) {
rb = b;
break;
}
@ -254,7 +255,7 @@ static inline dma_addr_t map_single(struct device *dev, void *ptr, size_t size,
if (buf == NULL) {
dev_err(dev, "%s: unable to map unsafe buffer %p!\n",
__func__, ptr);
return ~0;
return DMA_ERROR_CODE;
}
dev_dbg(dev, "%s: unsafe buffer %p (dma=%#x) mapped to %p (dma=%#x)\n",
@ -307,8 +308,9 @@ static inline void unmap_single(struct device *dev, struct safe_buffer *buf,
* substitute the safe buffer for the unsafe one.
* (basically move the buffer from an unsafe area to a safe one)
*/
dma_addr_t __dma_map_page(struct device *dev, struct page *page,
unsigned long offset, size_t size, enum dma_data_direction dir)
static dma_addr_t dmabounce_map_page(struct device *dev, struct page *page,
unsigned long offset, size_t size, enum dma_data_direction dir,
struct dma_attrs *attrs)
{
dma_addr_t dma_addr;
int ret;
@ -320,21 +322,20 @@ dma_addr_t __dma_map_page(struct device *dev, struct page *page,
ret = needs_bounce(dev, dma_addr, size);
if (ret < 0)
return ~0;
return DMA_ERROR_CODE;
if (ret == 0) {
__dma_page_cpu_to_dev(page, offset, size, dir);
arm_dma_ops.sync_single_for_device(dev, dma_addr, size, dir);
return dma_addr;
}
if (PageHighMem(page)) {
dev_err(dev, "DMA buffer bouncing of HIGHMEM pages is not supported\n");
return ~0;
return DMA_ERROR_CODE;
}
return map_single(dev, page_address(page) + offset, size, dir);
}
EXPORT_SYMBOL(__dma_map_page);
/*
* see if a mapped address was really a "safe" buffer and if so, copy
@ -342,8 +343,8 @@ EXPORT_SYMBOL(__dma_map_page);
* the safe buffer. (basically return things back to the way they
* should be)
*/
void __dma_unmap_page(struct device *dev, dma_addr_t dma_addr, size_t size,
enum dma_data_direction dir)
static void dmabounce_unmap_page(struct device *dev, dma_addr_t dma_addr, size_t size,
enum dma_data_direction dir, struct dma_attrs *attrs)
{
struct safe_buffer *buf;
@ -352,19 +353,18 @@ void __dma_unmap_page(struct device *dev, dma_addr_t dma_addr, size_t size,
buf = find_safe_buffer_dev(dev, dma_addr, __func__);
if (!buf) {
__dma_page_dev_to_cpu(pfn_to_page(dma_to_pfn(dev, dma_addr)),
dma_addr & ~PAGE_MASK, size, dir);
arm_dma_ops.sync_single_for_cpu(dev, dma_addr, size, dir);
return;
}
unmap_single(dev, buf, size, dir);
}
EXPORT_SYMBOL(__dma_unmap_page);
int dmabounce_sync_for_cpu(struct device *dev, dma_addr_t addr,
unsigned long off, size_t sz, enum dma_data_direction dir)
static int __dmabounce_sync_for_cpu(struct device *dev, dma_addr_t addr,
size_t sz, enum dma_data_direction dir)
{
struct safe_buffer *buf;
unsigned long off;
dev_dbg(dev, "%s(dma=%#x,off=%#lx,sz=%zx,dir=%x)\n",
__func__, addr, off, sz, dir);
@ -373,6 +373,8 @@ int dmabounce_sync_for_cpu(struct device *dev, dma_addr_t addr,
if (!buf)
return 1;
off = addr - buf->safe_dma_addr;
BUG_ON(buf->direction != dir);
dev_dbg(dev, "%s: unsafe buffer %p (dma=%#x) mapped to %p (dma=%#x)\n",
@ -388,12 +390,21 @@ int dmabounce_sync_for_cpu(struct device *dev, dma_addr_t addr,
}
return 0;
}
EXPORT_SYMBOL(dmabounce_sync_for_cpu);
int dmabounce_sync_for_device(struct device *dev, dma_addr_t addr,
unsigned long off, size_t sz, enum dma_data_direction dir)
static void dmabounce_sync_for_cpu(struct device *dev,
dma_addr_t handle, size_t size, enum dma_data_direction dir)
{
if (!__dmabounce_sync_for_cpu(dev, handle, size, dir))
return;
arm_dma_ops.sync_single_for_cpu(dev, handle, size, dir);
}
static int __dmabounce_sync_for_device(struct device *dev, dma_addr_t addr,
size_t sz, enum dma_data_direction dir)
{
struct safe_buffer *buf;
unsigned long off;
dev_dbg(dev, "%s(dma=%#x,off=%#lx,sz=%zx,dir=%x)\n",
__func__, addr, off, sz, dir);
@ -402,6 +413,8 @@ int dmabounce_sync_for_device(struct device *dev, dma_addr_t addr,
if (!buf)
return 1;
off = addr - buf->safe_dma_addr;
BUG_ON(buf->direction != dir);
dev_dbg(dev, "%s: unsafe buffer %p (dma=%#x) mapped to %p (dma=%#x)\n",
@ -417,7 +430,38 @@ int dmabounce_sync_for_device(struct device *dev, dma_addr_t addr,
}
return 0;
}
EXPORT_SYMBOL(dmabounce_sync_for_device);
static void dmabounce_sync_for_device(struct device *dev,
dma_addr_t handle, size_t size, enum dma_data_direction dir)
{
if (!__dmabounce_sync_for_device(dev, handle, size, dir))
return;
arm_dma_ops.sync_single_for_device(dev, handle, size, dir);
}
static int dmabounce_set_mask(struct device *dev, u64 dma_mask)
{
if (dev->archdata.dmabounce)
return 0;
return arm_dma_ops.set_dma_mask(dev, dma_mask);
}
static struct dma_map_ops dmabounce_ops = {
.alloc = arm_dma_alloc,
.free = arm_dma_free,
.mmap = arm_dma_mmap,
.map_page = dmabounce_map_page,
.unmap_page = dmabounce_unmap_page,
.sync_single_for_cpu = dmabounce_sync_for_cpu,
.sync_single_for_device = dmabounce_sync_for_device,
.map_sg = arm_dma_map_sg,
.unmap_sg = arm_dma_unmap_sg,
.sync_sg_for_cpu = arm_dma_sync_sg_for_cpu,
.sync_sg_for_device = arm_dma_sync_sg_for_device,
.set_dma_mask = dmabounce_set_mask,
};
static int dmabounce_init_pool(struct dmabounce_pool *pool, struct device *dev,
const char *name, unsigned long size)
@ -479,6 +523,7 @@ int dmabounce_register_dev(struct device *dev, unsigned long small_buffer_size,
#endif
dev->archdata.dmabounce = device_info;
set_dma_ops(dev, &dmabounce_ops);
dev_info(dev, "dmabounce: registered device\n");
@ -497,6 +542,7 @@ void dmabounce_unregister_dev(struct device *dev)
struct dmabounce_device_info *device_info = dev->archdata.dmabounce;
dev->archdata.dmabounce = NULL;
set_dma_ops(dev, NULL);
if (!device_info) {
dev_warn(dev,

4
arch/arm/include/asm/device.h
View file

@ -7,12 +7,16 @@
#define ASMARM_DEVICE_H
struct dev_archdata {
struct dma_map_ops *dma_ops;
#ifdef CONFIG_DMABOUNCE
struct dmabounce_device_info *dmabounce;
#endif
#ifdef CONFIG_IOMMU_API
void *iommu; /* private IOMMU data */
#endif
#ifdef CONFIG_ARM_DMA_USE_IOMMU
struct dma_iommu_mapping *mapping;
#endif
};
struct omap_device;

15
arch/arm/include/asm/dma-contiguous.h Normal file
View file

@ -0,0 +1,15 @@
#ifndef ASMARM_DMA_CONTIGUOUS_H
#define ASMARM_DMA_CONTIGUOUS_H
#ifdef __KERNEL__
#ifdef CONFIG_CMA
#include <linux/types.h>
#include <asm-generic/dma-contiguous.h>
void dma_contiguous_early_fixup(phys_addr_t base, unsigned long size);
#endif
#endif
#endif

34
arch/arm/include/asm/dma-iommu.h Normal file
View file

@ -0,0 +1,34 @@
#ifndef ASMARM_DMA_IOMMU_H
#define ASMARM_DMA_IOMMU_H
#ifdef __KERNEL__
#include <linux/mm_types.h>
#include <linux/scatterlist.h>
#include <linux/dma-debug.h>
#include <linux/kmemcheck.h>
struct dma_iommu_mapping {
/* iommu specific data */
struct iommu_domain *domain;
void *bitmap;
size_t bits;
unsigned int order;
dma_addr_t base;
spinlock_t lock;
struct kref kref;
};
struct dma_iommu_mapping *
arm_iommu_create_mapping(struct bus_type *bus, dma_addr_t base, size_t size,
int order);
void arm_iommu_release_mapping(struct dma_iommu_mapping *mapping);
int arm_iommu_attach_device(struct device *dev,
struct dma_iommu_mapping *mapping);
#endif /* __KERNEL__ */
#endif

407
arch/arm/include/asm/dma-mapping.h
View file

@ -5,11 +5,35 @@
#include <linux/mm_types.h>
#include <linux/scatterlist.h>
#include <linux/dma-attrs.h>
#include <linux/dma-debug.h>
#include <asm-generic/dma-coherent.h>
#include <asm/memory.h>
#define DMA_ERROR_CODE (~0)
extern struct dma_map_ops arm_dma_ops;
static inline struct dma_map_ops *get_dma_ops(struct device *dev)
{
if (dev && dev->archdata.dma_ops)
return dev->archdata.dma_ops;
return &arm_dma_ops;
}
static inline void set_dma_ops(struct device *dev, struct dma_map_ops *ops)
{
BUG_ON(!dev);
dev->archdata.dma_ops = ops;
}
#include <asm-generic/dma-mapping-common.h>
static inline int dma_set_mask(struct device *dev, u64 mask)
{
return get_dma_ops(dev)->set_dma_mask(dev, mask);
}
#ifdef __arch_page_to_dma
#error Please update to __arch_pfn_to_dma
#endif
@ -61,69 +85,12 @@ static inline dma_addr_t virt_to_dma(struct device *dev, void *addr)
}
#endif
/*
* The DMA API is built upon the notion of "buffer ownership". A buffer
* is either exclusively owned by the CPU (and therefore may be accessed
* by it) or exclusively owned by the DMA device. These helper functions
* represent the transitions between these two ownership states.
*
* Note, however, that on later ARMs, this notion does not work due to
* speculative prefetches. We model our approach on the assumption that
* the CPU does do speculative prefetches, which means we clean caches
* before transfers and delay cache invalidation until transfer completion.
*
* Private support functions: these are not part of the API and are
* liable to change. Drivers must not use these.
*/
static inline void __dma_single_cpu_to_dev(const void *kaddr, size_t size,
enum dma_data_direction dir)
{
extern void ___dma_single_cpu_to_dev(const void *, size_t,
enum dma_data_direction);
if (!arch_is_coherent())
___dma_single_cpu_to_dev(kaddr, size, dir);
}
static inline void __dma_single_dev_to_cpu(const void *kaddr, size_t size,
enum dma_data_direction dir)
{
extern void ___dma_single_dev_to_cpu(const void *, size_t,
enum dma_data_direction);
if (!arch_is_coherent())
___dma_single_dev_to_cpu(kaddr, size, dir);
}
static inline void __dma_page_cpu_to_dev(struct page *page, unsigned long off,
size_t size, enum dma_data_direction dir)
{
extern void ___dma_page_cpu_to_dev(struct page *, unsigned long,
size_t, enum dma_data_direction);
if (!arch_is_coherent())
___dma_page_cpu_to_dev(page, off, size, dir);
}
static inline void __dma_page_dev_to_cpu(struct page *page, unsigned long off,
size_t size, enum dma_data_direction dir)
{
extern void ___dma_page_dev_to_cpu(struct page *, unsigned long,
size_t, enum dma_data_direction);
if (!arch_is_coherent())
___dma_page_dev_to_cpu(page, off, size, dir);
}
extern int dma_supported(struct device *, u64);
extern int dma_set_mask(struct device *, u64);
/*
* DMA errors are defined by all-bits-set in the DMA address.
*/
static inline int dma_mapping_error(struct device *dev, dma_addr_t dma_addr)
{
return dma_addr == ~0;
return dma_addr == DMA_ERROR_CODE;
}
/*
@ -141,69 +108,118 @@ static inline void dma_free_noncoherent(struct device *dev, size_t size,
{
}
extern int dma_supported(struct device *dev, u64 mask);
/**
* dma_alloc_coherent - allocate consistent memory for DMA
* arm_dma_alloc - allocate consistent memory for DMA
* @dev: valid struct device pointer, or NULL for ISA and EISA-like devices
* @size: required memory size
* @handle: bus-specific DMA address
* @attrs: optinal attributes that specific mapping properties
*
* Allocate some uncached, unbuffered memory for a device for
* performing DMA. This function allocates pages, and will
* return the CPU-viewed address, and sets @handle to be the
* device-viewed address.
* Allocate some memory for a device for performing DMA. This function
* allocates pages, and will return the CPU-viewed address, and sets @handle
* to be the device-viewed address.
*/
extern void *dma_alloc_coherent(struct device *, size_t, dma_addr_t *, gfp_t);
extern void *arm_dma_alloc(struct device *dev, size_t size, dma_addr_t *handle,
gfp_t gfp, struct dma_attrs *attrs);
#define dma_alloc_coherent(d, s, h, f) dma_alloc_attrs(d, s, h, f, NULL)
static inline void *dma_alloc_attrs(struct device *dev, size_t size,
dma_addr_t *dma_handle, gfp_t flag,
struct dma_attrs *attrs)
{
struct dma_map_ops *ops = get_dma_ops(dev);
void *cpu_addr;
BUG_ON(!ops);
cpu_addr = ops->alloc(dev, size, dma_handle, flag, attrs);
debug_dma_alloc_coherent(dev, size, *dma_handle, cpu_addr);
return cpu_addr;
}
/**
* dma_free_coherent - free memory allocated by dma_alloc_coherent
* arm_dma_free - free memory allocated by arm_dma_alloc
* @dev: valid struct device pointer, or NULL for ISA and EISA-like devices
* @size: size of memory originally requested in dma_alloc_coherent
* @cpu_addr: CPU-view address returned from dma_alloc_coherent
* @handle: device-view address returned from dma_alloc_coherent
* @attrs: optinal attributes that specific mapping properties
*
* Free (and unmap) a DMA buffer previously allocated by
* dma_alloc_coherent().
* arm_dma_alloc().
*
* References to memory and mappings associated with cpu_addr/handle
* during and after this call executing are illegal.
*/
extern void dma_free_coherent(struct device *, size_t, void *, dma_addr_t);
extern void arm_dma_free(struct device *dev, size_t size, void *cpu_addr,
dma_addr_t handle, struct dma_attrs *attrs);
#define dma_free_coherent(d, s, c, h) dma_free_attrs(d, s, c, h, NULL)
static inline void dma_free_attrs(struct device *dev, size_t size,
void *cpu_addr, dma_addr_t dma_handle,
struct dma_attrs *attrs)
{
struct dma_map_ops *ops = get_dma_ops(dev);
BUG_ON(!ops);
debug_dma_free_coherent(dev, size, cpu_addr, dma_handle);
ops->free(dev, size, cpu_addr, dma_handle, attrs);
}
/**
* dma_mmap_coherent - map a coherent DMA allocation into user space
* arm_dma_mmap - map a coherent DMA allocation into user space
* @dev: valid struct device pointer, or NULL for ISA and EISA-like devices
* @vma: vm_area_struct describing requested user mapping
* @cpu_addr: kernel CPU-view address returned from dma_alloc_coherent
* @handle: device-view address returned from dma_alloc_coherent
* @size: size of memory originally requested in dma_alloc_coherent
* @attrs: optinal attributes that specific mapping properties
*
* Map a coherent DMA buffer previously allocated by dma_alloc_coherent
* into user space. The coherent DMA buffer must not be freed by the
* driver until the user space mapping has been released.
*/
int dma_mmap_coherent(struct device *, struct vm_area_struct *,
void *, dma_addr_t, size_t);
extern int arm_dma_mmap(struct device *dev, struct vm_area_struct *vma,
void *cpu_addr, dma_addr_t dma_addr, size_t size,
struct dma_attrs *attrs);
#define dma_mmap_coherent(d, v, c, h, s) dma_mmap_attrs(d, v, c, h, s, NULL)
/**
* dma_alloc_writecombine - allocate writecombining memory for DMA
* @dev: valid struct device pointer, or NULL for ISA and EISA-like devices
* @size: required memory size
* @handle: bus-specific DMA address
*
* Allocate some uncached, buffered memory for a device for
* performing DMA. This function allocates pages, and will
* return the CPU-viewed address, and sets @handle to be the
* device-viewed address.
*/
extern void *dma_alloc_writecombine(struct device *, size_t, dma_addr_t *,
gfp_t);
static inline int dma_mmap_attrs(struct device *dev, struct vm_area_struct *vma,
void *cpu_addr, dma_addr_t dma_addr,
size_t size, struct dma_attrs *attrs)
{
struct dma_map_ops *ops = get_dma_ops(dev);
BUG_ON(!ops);
return ops->mmap(dev, vma, cpu_addr, dma_addr, size, attrs);
}
#define dma_free_writecombine(dev,size,cpu_addr,handle) \
dma_free_coherent(dev,size,cpu_addr,handle)
static inline void *dma_alloc_writecombine(struct device *dev, size_t size,
dma_addr_t *dma_handle, gfp_t flag)
{
DEFINE_DMA_ATTRS(attrs);
dma_set_attr(DMA_ATTR_WRITE_COMBINE, &attrs);
return dma_alloc_attrs(dev, size, dma_handle, flag, &attrs);
}
int dma_mmap_writecombine(struct device *, struct vm_area_struct *,
void *, dma_addr_t, size_t);
static inline void dma_free_writecombine(struct device *dev, size_t size,
void *cpu_addr, dma_addr_t dma_handle)
{
DEFINE_DMA_ATTRS(attrs);
dma_set_attr(DMA_ATTR_WRITE_COMBINE, &attrs);
return dma_free_attrs(dev, size, cpu_addr, dma_handle, &attrs);
}
static inline int dma_mmap_writecombine(struct device *dev, struct vm_area_struct *vma,
void *cpu_addr, dma_addr_t dma_addr, size_t size)
{
DEFINE_DMA_ATTRS(attrs);
dma_set_attr(DMA_ATTR_WRITE_COMBINE, &attrs);
return dma_mmap_attrs(dev, vma, cpu_addr, dma_addr, size, &attrs);
}
/*
* This can be called during boot to increase the size of the consistent
@ -212,8 +228,6 @@ int dma_mmap_writecombine(struct device *, struct vm_area_struct *,
*/
extern void __init init_consistent_dma_size(unsigned long size);
#ifdef CONFIG_DMABOUNCE
/*
* For SA-1111, IXP425, and ADI systems the dma-mapping functions are "magic"
* and utilize bounce buffers as needed to work around limited DMA windows.
@ -253,222 +267,19 @@ extern int dmabounce_register_dev(struct device *, unsigned long,
*/
extern void dmabounce_unregister_dev(struct device *);
/*
* The DMA API, implemented by dmabounce.c. See below for descriptions.
*/
extern dma_addr_t __dma_map_page(struct device *, struct page *,
unsigned long, size_t, enum dma_data_direction);
extern void __dma_unmap_page(struct device *, dma_addr_t, size_t,
enum dma_data_direction);
/*
* Private functions
*/
int dmabounce_sync_for_cpu(struct device *, dma_addr_t, unsigned long,
size_t, enum dma_data_direction);
int dmabounce_sync_for_device(struct device *, dma_addr_t, unsigned long,
size_t, enum dma_data_direction);
#else
static inline int dmabounce_sync_for_cpu(struct device *d, dma_addr_t addr,
unsigned long offset, size_t size, enum dma_data_direction dir)
{
return 1;
}
static inline int dmabounce_sync_for_device(struct device *d, dma_addr_t addr,
unsigned long offset, size_t size, enum dma_data_direction dir)
{
return 1;
}
static inline dma_addr_t __dma_map_page(struct device *dev, struct page *page,
unsigned long offset, size_t size, enum dma_data_direction dir)
{
__dma_page_cpu_to_dev(page, offset, size, dir);
return pfn_to_dma(dev, page_to_pfn(page)) + offset;
}
static inline void __dma_unmap_page(struct device *dev, dma_addr_t handle,
size_t size, enum dma_data_direction dir)
{
__dma_page_dev_to_cpu(pfn_to_page(dma_to_pfn(dev, handle)),
handle & ~PAGE_MASK, size, dir);
}
#endif /* CONFIG_DMABOUNCE */
/**
* dma_map_single - map a single buffer for streaming DMA
* @dev: valid struct device pointer, or NULL for ISA and EISA-like devices
* @cpu_addr: CPU direct mapped address of buffer
* @size: size of buffer to map
* @dir: DMA transfer direction
*
* Ensure that any data held in the cache is appropriately discarded
* or written back.
*
* The device owns this memory once this call has completed. The CPU
* can regain ownership by calling dma_unmap_single() or
* dma_sync_single_for_cpu().
*/
static inline dma_addr_t dma_map_single(struct device *dev, void *cpu_addr,
size_t size, enum dma_data_direction dir)
{
unsigned long offset;
struct page *page;
dma_addr_t addr;
BUG_ON(!virt_addr_valid(cpu_addr));
BUG_ON(!virt_addr_valid(cpu_addr + size - 1));
BUG_ON(!valid_dma_direction(dir));
page = virt_to_page(cpu_addr);
offset = (unsigned long)cpu_addr & ~PAGE_MASK;
addr = __dma_map_page(dev, page, offset, size, dir);
debug_dma_map_page(dev, page, offset, size, dir, addr, true);
return addr;
}
/**
* dma_map_page - map a portion of a page for streaming DMA
* @dev: valid struct device pointer, or NULL for ISA and EISA-like devices
* @page: page that buffer resides in
* @offset: offset into page for start of buffer
* @size: size of buffer to map
* @dir: DMA transfer direction
*
* Ensure that any data held in the cache is appropriately discarded
* or written back.
*
* The device owns this memory once this call has completed. The CPU
* can regain ownership by calling dma_unmap_page().
*/
static inline dma_addr_t dma_map_page(struct device *dev, struct page *page,
unsigned long offset, size_t size, enum dma_data_direction dir)
{
dma_addr_t addr;
BUG_ON(!valid_dma_direction(dir));
addr = __dma_map_page(dev, page, offset, size, dir);
debug_dma_map_page(dev, page, offset, size, dir, addr, false);
return addr;
}
/**
* dma_unmap_single - unmap a single buffer previously mapped
* @dev: valid struct device pointer, or NULL for ISA and EISA-like devices
* @handle: DMA address of buffer
* @size: size of buffer (same as passed to dma_map_single)
* @dir: DMA transfer direction (same as passed to dma_map_single)
*
* Unmap a single streaming mode DMA translation. The handle and size
* must match what was provided in the previous dma_map_single() call.
* All other usages are undefined.
*
* After this call, reads by the CPU to the buffer are guaranteed to see
* whatever the device wrote there.
*/
static inline void dma_unmap_single(struct device *dev, dma_addr_t handle,
size_t size, enum dma_data_direction dir)
{
debug_dma_unmap_page(dev, handle, size, dir, true);
__dma_unmap_page(dev, handle, size, dir);
}
/**
* dma_unmap_page - unmap a buffer previously mapped through dma_map_page()
* @dev: valid struct device pointer, or NULL for ISA and EISA-like devices
* @handle: DMA address of buffer
* @size: size of buffer (same as passed to dma_map_page)
* @dir: DMA transfer direction (same as passed to dma_map_page)
*
* Unmap a page streaming mode DMA translation. The handle and size
* must match what was provided in the previous dma_map_page() call.
* All other usages are undefined.
*
* After this call, reads by the CPU to the buffer are guaranteed to see
* whatever the device wrote there.
*/
static inline void dma_unmap_page(struct device *dev, dma_addr_t handle,
size_t size, enum dma_data_direction dir)
{
debug_dma_unmap_page(dev, handle, size, dir, false);
__dma_unmap_page(dev, handle, size, dir);
}
/**
* dma_sync_single_range_for_cpu
* @dev: valid struct device pointer, or NULL for ISA and EISA-like devices
* @handle: DMA address of buffer
* @offset: offset of region to start sync
* @size: size of region to sync
* @dir: DMA transfer direction (same as passed to dma_map_single)
*
* Make physical memory consistent for a single streaming mode DMA
* translation after a transfer.
*
* If you perform a dma_map_single() but wish to interrogate the
* buffer using the cpu, yet do not wish to teardown the PCI dma
* mapping, you must call this function before doing so. At the
* next point you give the PCI dma address back to the card, you
* must first the perform a dma_sync_for_device, and then the
* device again owns the buffer.
*/
static inline void dma_sync_single_range_for_cpu(struct device *dev,
dma_addr_t handle, unsigned long offset, size_t size,
enum dma_data_direction dir)
{
BUG_ON(!valid_dma_direction(dir));
debug_dma_sync_single_for_cpu(dev, handle + offset, size, dir);
if (!dmabounce_sync_for_cpu(dev, handle, offset, size, dir))
return;
__dma_single_dev_to_cpu(dma_to_virt(dev, handle) + offset, size, dir);
}
static inline void dma_sync_single_range_for_device(struct device *dev,
dma_addr_t handle, unsigned long offset, size_t size,
enum dma_data_direction dir)
{
BUG_ON(!valid_dma_direction(dir));
debug_dma_sync_single_for_device(dev, handle + offset, size, dir);
if (!dmabounce_sync_for_device(dev, handle, offset, size, dir))
return;
__dma_single_cpu_to_dev(dma_to_virt(dev, handle) + offset, size, dir);
}
static inline void dma_sync_single_for_cpu(struct device *dev,
dma_addr_t handle, size_t size, enum dma_data_direction dir)
{
dma_sync_single_range_for_cpu(dev, handle, 0, size, dir);
}
static inline void dma_sync_single_for_device(struct device *dev,
dma_addr_t handle, size_t size, enum dma_data_direction dir)
{
dma_sync_single_range_for_device(dev, handle, 0, size, dir);
}
/*
* The scatter list versions of the above methods.
*/
extern int dma_map_sg(struct device *, struct scatterlist *, int,
extern int arm_dma_map_sg(struct device *, struct scatterlist *, int,
enum dma_data_direction, struct dma_attrs *attrs);
extern void arm_dma_unmap_sg(struct device *, struct scatterlist *, int,
enum dma_data_direction, struct dma_attrs *attrs);
extern void arm_dma_sync_sg_for_cpu(struct device *, struct scatterlist *, int,
enum dma_data_direction);
extern void dma_unmap_sg(struct device *, struct scatterlist *, int,
extern void arm_dma_sync_sg_for_device(struct device *, struct scatterlist *, int,
enum dma_data_direction);
extern void dma_sync_sg_for_cpu(struct device *, struct scatterlist *, int,
enum dma_data_direction);
extern void dma_sync_sg_for_device(struct device *, struct scatterlist *, int,
enum dma_data_direction);
#endif /* __KERNEL__ */
#endif

1
arch/arm/include/asm/mach/map.h
View file

@ -30,6 +30,7 @@ struct map_desc {
#define MT_MEMORY_DTCM 12
#define MT_MEMORY_ITCM 13
#define MT_MEMORY_SO 14
#define MT_MEMORY_DMA_READY 15
#ifdef CONFIG_MMU
extern void iotable_init(struct map_desc *, int);

9
arch/arm/kernel/setup.c
View file

@ -81,6 +81,7 @@ __setup("fpe=", fpe_setup);
extern void paging_init(struct machine_desc *desc);
extern void sanity_check_meminfo(void);
extern void reboot_setup(char *str);
extern void setup_dma_zone(struct machine_desc *desc);
unsigned int processor_id;
EXPORT_SYMBOL(processor_id);
@ -939,12 +940,8 @@ void __init setup_arch(char **cmdline_p)
machine_desc = mdesc;
machine_name = mdesc->name;
#ifdef CONFIG_ZONE_DMA
if (mdesc->dma_zone_size) {
extern unsigned long arm_dma_zone_size;
arm_dma_zone_size = mdesc->dma_zone_size;
}
#endif
setup_dma_zone(mdesc);
if (mdesc->restart_mode)
reboot_setup(&mdesc->restart_mode);

1348
arch/arm/mm/dma-mapping.c
View file

File diff suppressed because it is too large Load diff

23
arch/arm/mm/init.c
View file

@ -20,6 +20,7 @@
#include <linux/highmem.h>
#include <linux/gfp.h>
#include <linux/memblock.h>
#include <linux/dma-contiguous.h>
#include <asm/mach-types.h>
#include <asm/memblock.h>
@ -226,6 +227,17 @@ static void __init arm_adjust_dma_zone(unsigned long *size, unsigned long *hole,
}
#endif
void __init setup_dma_zone(struct machine_desc *mdesc)
{
#ifdef CONFIG_ZONE_DMA
if (mdesc->dma_zone_size) {
arm_dma_zone_size = mdesc->dma_zone_size;
arm_dma_limit = PHYS_OFFSET + arm_dma_zone_size - 1;
} else
arm_dma_limit = 0xffffffff;
#endif
}
static void __init arm_bootmem_free(unsigned long min, unsigned long max_low,
unsigned long max_high)
{
@ -273,12 +285,9 @@ static void __init arm_bootmem_free(unsigned long min, unsigned long max_low,
* Adjust the sizes according to any special requirements for
* this machine type.
*/
if (arm_dma_zone_size) {
if (arm_dma_zone_size)
arm_adjust_dma_zone(zone_size, zhole_size,
arm_dma_zone_size >> PAGE_SHIFT);
arm_dma_limit = PHYS_OFFSET + arm_dma_zone_size - 1;
} else
arm_dma_limit = 0xffffffff;
#endif
free_area_init_node(0, zone_size, min, zhole_size);
@ -364,6 +373,12 @@ void __init arm_memblock_init(struct meminfo *mi, struct machine_desc *mdesc)
if (mdesc->reserve)
mdesc->reserve();
/*
* reserve memory for DMA contigouos allocations,
* must come from DMA area inside low memory
*/
dma_contiguous_reserve(min(arm_dma_limit, arm_lowmem_limit));
arm_memblock_steal_permitted = false;
memblock_allow_resize();
memblock_dump_all();

3
arch/arm/mm/mm.h
View file

@ -67,5 +67,8 @@ extern u32 arm_dma_limit;
#define arm_dma_limit ((u32)~0)
#endif
extern phys_addr_t arm_lowmem_limit;
void __init bootmem_init(void);
void arm_mm_memblock_reserve(void);
void dma_contiguous_remap(void);

31
arch/arm/mm/mmu.c
View file

@ -288,6 +288,11 @@ static struct mem_type mem_types[] = {
PMD_SECT_UNCACHED | PMD_SECT_XN,
.domain = DOMAIN_KERNEL,
},
[MT_MEMORY_DMA_READY] = {
.prot_pte = L_PTE_PRESENT | L_PTE_YOUNG | L_PTE_DIRTY,
.prot_l1 = PMD_TYPE_TABLE,
.domain = DOMAIN_KERNEL,
},
};
const struct mem_type *get_mem_type(unsigned int type)
@ -429,6 +434,7 @@ static void __init build_mem_type_table(void)
if (arch_is_coherent() && cpu_is_xsc3()) {
mem_types[MT_MEMORY].prot_sect |= PMD_SECT_S;
mem_types[MT_MEMORY].prot_pte |= L_PTE_SHARED;
mem_types[MT_MEMORY_DMA_READY].prot_pte |= L_PTE_SHARED;
mem_types[MT_MEMORY_NONCACHED].prot_sect |= PMD_SECT_S;
mem_types[MT_MEMORY_NONCACHED].prot_pte |= L_PTE_SHARED;
}
@ -460,6 +466,7 @@ static void __init build_mem_type_table(void)
mem_types[MT_DEVICE_CACHED].prot_pte |= L_PTE_SHARED;
mem_types[MT_MEMORY].prot_sect |= PMD_SECT_S;
mem_types[MT_MEMORY].prot_pte |= L_PTE_SHARED;
mem_types[MT_MEMORY_DMA_READY].prot_pte |= L_PTE_SHARED;
mem_types[MT_MEMORY_NONCACHED].prot_sect |= PMD_SECT_S;
mem_types[MT_MEMORY_NONCACHED].prot_pte |= L_PTE_SHARED;
}
@ -512,6 +519,7 @@ static void __init build_mem_type_table(void)
mem_types[MT_HIGH_VECTORS].prot_l1 |= ecc_mask;
mem_types[MT_MEMORY].prot_sect |= ecc_mask | cp->pmd;
mem_types[MT_MEMORY].prot_pte |= kern_pgprot;
mem_types[MT_MEMORY_DMA_READY].prot_pte |= kern_pgprot;
mem_types[MT_MEMORY_NONCACHED].prot_sect |= ecc_mask;
mem_types[MT_ROM].prot_sect |= cp->pmd;
@ -596,7 +604,7 @@ static void __init alloc_init_section(pud_t *pud, unsigned long addr,
* L1 entries, whereas PGDs refer to a group of L1 entries making
* up one logical pointer to an L2 table.
*/
if (((addr | end | phys) & ~SECTION_MASK) == 0) {
if (type->prot_sect && ((addr | end | phys) & ~SECTION_MASK) == 0) {
pmd_t *p = pmd;
#ifndef CONFIG_ARM_LPAE
@ -814,7 +822,7 @@ static int __init early_vmalloc(char *arg)
}
early_param("vmalloc", early_vmalloc);
static phys_addr_t lowmem_limit __initdata = 0;
phys_addr_t arm_lowmem_limit __initdata = 0;
void __init sanity_check_meminfo(void)
{
@ -897,8 +905,8 @@ void __init sanity_check_meminfo(void)
bank->size = newsize;
}
#endif
if (!bank->highmem && bank->start + bank->size > lowmem_limit)
lowmem_limit = bank->start + bank->size;
if (!bank->highmem && bank->start + bank->size > arm_lowmem_limit)
arm_lowmem_limit = bank->start + bank->size;
j++;
}
@ -923,8 +931,8 @@ void __init sanity_check_meminfo(void)
}
#endif
meminfo.nr_banks = j;
high_memory = __va(lowmem_limit - 1) + 1;
memblock_set_current_limit(lowmem_limit);
high_memory = __va(arm_lowmem_limit - 1) + 1;
memblock_set_current_limit(arm_lowmem_limit);
}
static inline void prepare_page_table(void)
@ -949,8 +957,8 @@ static inline void prepare_page_table(void)
* Find the end of the first block of lowmem.
*/
end = memblock.memory.regions[0].base + memblock.memory.regions[0].size;
if (end >= lowmem_limit)
end = lowmem_limit;
if (end >= arm_lowmem_limit)
end = arm_lowmem_limit;
/*
* Clear out all the kernel space mappings, except for the first
@ -1093,8 +1101,8 @@ static void __init map_lowmem(void)
phys_addr_t end = start + reg->size;
struct map_desc map;
if (end > lowmem_limit)
end = lowmem_limit;
if (end > arm_lowmem_limit)
end = arm_lowmem_limit;
if (start >= end)
break;
@ -1115,11 +1123,12 @@ void __init paging_init(struct machine_desc *mdesc)
{
void *zero_page;
memblock_set_current_limit(lowmem_limit);
memblock_set_current_limit(arm_lowmem_limit);
build_mem_type_table();
prepare_page_table();
map_lowmem();
dma_contiguous_remap();
devicemaps_init(mdesc);
kmap_init();

2
arch/arm/mm/vmregion.h
View file

@ -17,7 +17,7 @@ struct arm_vmregion {
struct list_head vm_list;
unsigned long vm_start;
unsigned long vm_end;
struct page *vm_pages;
void *priv;
int vm_active;
const void *caller;
};

1
arch/x86/Kconfig
View file

@ -32,6 +32,7 @@ config X86
select ARCH_WANT_OPTIONAL_GPIOLIB
select ARCH_WANT_FRAME_POINTERS
select HAVE_DMA_ATTRS
select HAVE_DMA_CONTIGUOUS if !SWIOTLB
select HAVE_KRETPROBES
select HAVE_OPTPROBES
select HAVE_FTRACE_MCOUNT_RECORD

13
arch/x86/include/asm/dma-contiguous.h Normal file
View file

@ -0,0 +1,13 @@
#ifndef ASMX86_DMA_CONTIGUOUS_H
#define ASMX86_DMA_CONTIGUOUS_H
#ifdef __KERNEL__
#include <linux/types.h>
#include <asm-generic/dma-contiguous.h>
static inline void
dma_contiguous_early_fixup(phys_addr_t base, unsigned long size) { }
#endif
#endif

5
arch/x86/include/asm/dma-mapping.h
View file

@ -13,6 +13,7 @@
#include <asm/io.h>
#include <asm/swiotlb.h>
#include <asm-generic/dma-coherent.h>
#include <linux/dma-contiguous.h>
#ifdef CONFIG_ISA
# define ISA_DMA_BIT_MASK DMA_BIT_MASK(24)
@ -62,6 +63,10 @@ extern void *dma_generic_alloc_coherent(struct device *dev, size_t size,
dma_addr_t *dma_addr, gfp_t flag,
struct dma_attrs *attrs);
extern void dma_generic_free_coherent(struct device *dev, size_t size,
void *vaddr, dma_addr_t dma_addr,
struct dma_attrs *attrs);
#ifdef CONFIG_X86_DMA_REMAP /* Platform code defines bridge-specific code */
extern bool dma_capable(struct device *dev, dma_addr_t addr, size_t size);
extern dma_addr_t phys_to_dma(struct device *dev, phys_addr_t paddr);

18
arch/x86/kernel/pci-dma.c
View file

@ -100,14 +100,18 @@ void *dma_generic_alloc_coherent(struct device *dev, size_t size,
struct dma_attrs *attrs)
{
unsigned long dma_mask;
struct page *page;
struct page *page = NULL;
unsigned int count = PAGE_ALIGN(size) >> PAGE_SHIFT;
dma_addr_t addr;
dma_mask = dma_alloc_coherent_mask(dev, flag);
flag |= __GFP_ZERO;
again:
page = alloc_pages_node(dev_to_node(dev), flag, get_order(size));
if (!(flag & GFP_ATOMIC))
page = dma_alloc_from_contiguous(dev, count, get_order(size));
if (!page)
page = alloc_pages_node(dev_to_node(dev), flag, get_order(size));
if (!page)
return NULL;
@ -127,6 +131,16 @@ again:
return page_address(page);
}
void dma_generic_free_coherent(struct device *dev, size_t size, void *vaddr,
dma_addr_t dma_addr, struct dma_attrs *attrs)
{
unsigned int count = PAGE_ALIGN(size) >> PAGE_SHIFT;
struct page *page = virt_to_page(vaddr);
if (!dma_release_from_contiguous(dev, page, count))
free_pages((unsigned long)vaddr, get_order(size));
}
/*
* See <Documentation/x86/x86_64/boot-options.txt> for the iommu kernel
* parameter documentation.

8
arch/x86/kernel/pci-nommu.c
View file

@ -74,12 +74,6 @@ static int nommu_map_sg(struct device *hwdev, struct scatterlist *sg,
return nents;
}
static void nommu_free_coherent(struct device *dev, size_t size, void *vaddr,
dma_addr_t dma_addr, struct dma_attrs *attrs)
{
free_pages((unsigned long)vaddr, get_order(size));
}
static void nommu_sync_single_for_device(struct device *dev,
dma_addr_t addr, size_t size,
enum dma_data_direction dir)
@ -97,7 +91,7 @@ static void nommu_sync_sg_for_device(struct device *dev,
struct dma_map_ops nommu_dma_ops = {
.alloc = dma_generic_alloc_coherent,
.free = nommu_free_coherent,
.free = dma_generic_free_coherent,
.map_sg = nommu_map_sg,
.map_page = nommu_map_page,
.sync_single_for_device = nommu_sync_single_for_device,

2
arch/x86/kernel/setup.c
View file

@ -49,6 +49,7 @@
#include <asm/pci-direct.h>
#include <linux/init_ohci1394_dma.h>
#include <linux/kvm_para.h>
#include <linux/dma-contiguous.h>
#include <linux/errno.h>
#include <linux/kernel.h>
@ -925,6 +926,7 @@ void __init setup_arch(char **cmdline_p)
}
#endif
memblock.current_limit = get_max_mapped();
dma_contiguous_reserve(0);
/*
* NOTE: On x86-32, only from this point on, fixmaps are ready for use.

89
drivers/base/Kconfig
View file

@ -192,4 +192,93 @@ config DMA_SHARED_BUFFER
APIs extension; the file's descriptor can then be passed on to other
driver.
config CMA
bool "Contiguous Memory Allocator (EXPERIMENTAL)"
depends on HAVE_DMA_CONTIGUOUS && HAVE_MEMBLOCK && EXPERIMENTAL
select MIGRATION
help
This enables the Contiguous Memory Allocator which allows drivers
to allocate big physically-contiguous blocks of memory for use with
hardware components that do not support I/O map nor scatter-gather.
For more information see <include/linux/dma-contiguous.h>.
If unsure, say "n".
if CMA
config CMA_DEBUG
bool "CMA debug messages (DEVELOPMENT)"
depends on DEBUG_KERNEL
help
Turns on debug messages in CMA. This produces KERN_DEBUG
messages for every CMA call as well as various messages while
processing calls such as dma_alloc_from_contiguous().
This option does not affect warning and error messages.
comment "Default contiguous memory area size:"
config CMA_SIZE_MBYTES
int "Size in Mega Bytes"
depends on !CMA_SIZE_SEL_PERCENTAGE
default 16
help
Defines the size (in MiB) of the default memory area for Contiguous
Memory Allocator.
config CMA_SIZE_PERCENTAGE
int "Percentage of total memory"
depends on !CMA_SIZE_SEL_MBYTES
default 10
help
Defines the size of the default memory area for Contiguous Memory
Allocator as a percentage of the total memory in the system.
choice
prompt "Selected region size"
default CMA_SIZE_SEL_ABSOLUTE
config CMA_SIZE_SEL_MBYTES
bool "Use mega bytes value only"
config CMA_SIZE_SEL_PERCENTAGE
bool "Use percentage value only"
config CMA_SIZE_SEL_MIN
bool "Use lower value (minimum)"
config CMA_SIZE_SEL_MAX
bool "Use higher value (maximum)"
endchoice
config CMA_ALIGNMENT
int "Maximum PAGE_SIZE order of alignment for contiguous buffers"
range 4 9
default 8
help
DMA mapping framework by default aligns all buffers to the smallest
PAGE_SIZE order which is greater than or equal to the requested buffer
size. This works well for buffers up to a few hundreds kilobytes, but
for larger buffers it just a memory waste. With this parameter you can
specify the maximum PAGE_SIZE order for contiguous buffers. Larger
buffers will be aligned only to this specified order. The order is
expressed as a power of two multiplied by the PAGE_SIZE.
For example, if your system defaults to 4KiB pages, the order value
of 8 means that the buffers will be aligned up to 1MiB only.
If unsure, leave the default value "8".
config CMA_AREAS
int "Maximum count of the CMA device-private areas"
default 7
help
CMA allows to create CMA areas for particular devices. This parameter
sets the maximum number of such device private CMA areas in the
system.
If unsure, leave the default value "7".
endif
endmenu

1
drivers/base/Makefile
View file

@ -6,6 +6,7 @@ obj-y := core.o bus.o dd.o syscore.o \
attribute_container.o transport_class.o \
topology.o
obj-$(CONFIG_DEVTMPFS) += devtmpfs.o
obj-$(CONFIG_CMA) += dma-contiguous.o
obj-y += power/
obj-$(CONFIG_HAS_DMA) += dma-mapping.o
obj-$(CONFIG_HAVE_GENERIC_DMA_COHERENT) += dma-coherent.o

42
drivers/base/dma-coherent.c
View file

@ -10,6 +10,7 @@
struct dma_coherent_mem {
void *virt_base;
dma_addr_t device_base;
phys_addr_t pfn_base;
int size;
int flags;
unsigned long *bitmap;
@ -44,6 +45,7 @@ int dma_declare_coherent_memory(struct device *dev, dma_addr_t bus_addr,
dev->dma_mem->virt_base = mem_base;
dev->dma_mem->device_base = device_addr;
dev->dma_mem->pfn_base = PFN_DOWN(bus_addr);
dev->dma_mem->size = pages;
dev->dma_mem->flags = flags;
@ -176,3 +178,43 @@ int dma_release_from_coherent(struct device *dev, int order, void *vaddr)
return 0;
}
EXPORT_SYMBOL(dma_release_from_coherent);
/**
* dma_mmap_from_coherent() - try to mmap the memory allocated from
* per-device coherent memory pool to userspace
* @dev: device from which the memory was allocated
* @vma: vm_area for the userspace memory
* @vaddr: cpu address returned by dma_alloc_from_coherent
* @size: size of the memory buffer allocated by dma_alloc_from_coherent
*
* This checks whether the memory was allocated from the per-device
* coherent memory pool and if so, maps that memory to the provided vma.
*
* Returns 1 if we correctly mapped the memory, or 0 if
* dma_release_coherent() should proceed with mapping memory from
* generic pools.
*/
int dma_mmap_from_coherent(struct device *dev, struct vm_area_struct *vma,
void *vaddr, size_t size, int *ret)
{
struct dma_coherent_mem *mem = dev ? dev->dma_mem : NULL;
if (mem && vaddr >= mem->virt_base && vaddr + size <=
(mem->virt_base + (mem->size << PAGE_SHIFT))) {
unsigned long off = vma->vm_pgoff;
int start = (vaddr - mem->virt_base) >> PAGE_SHIFT;
int user_count = (vma->vm_end - vma->vm_start) >> PAGE_SHIFT;
int count = size >> PAGE_SHIFT;
*ret = -ENXIO;
if (off < count && user_count <= count - off) {
unsigned pfn = mem->pfn_base + start + off;
*ret = remap_pfn_range(vma, vma->vm_start, pfn,
user_count << PAGE_SHIFT,
vma->vm_page_prot);
}
return 1;
}
return 0;
}
EXPORT_SYMBOL(dma_mmap_from_coherent);

401
drivers/base/dma-contiguous.c Normal file
View file

@ -0,0 +1,401 @@
/*
* Contiguous Memory Allocator for DMA mapping framework
* Copyright (c) 2010-2011 by Samsung Electronics.
* Written by:
* Marek Szyprowski <m.szyprowski@samsung.com>
* Michal Nazarewicz <mina86@mina86.com>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation; either version 2 of the
* License or (at your optional) any later version of the license.
*/
#define pr_fmt(fmt) "cma: " fmt
#ifdef CONFIG_CMA_DEBUG
#ifndef DEBUG
# define DEBUG
#endif
#endif
#include <asm/page.h>
#include <asm/dma-contiguous.h>
#include <linux/memblock.h>
#include <linux/err.h>
#include <linux/mm.h>
#include <linux/mutex.h>
#include <linux/page-isolation.h>
#include <linux/slab.h>
#include <linux/swap.h>
#include <linux/mm_types.h>
#include <linux/dma-contiguous.h>
#ifndef SZ_1M
#define SZ_1M (1 << 20)
#endif
struct cma {
unsigned long base_pfn;
unsigned long count;
unsigned long *bitmap;
};
struct cma *dma_contiguous_default_area;
#ifdef CONFIG_CMA_SIZE_MBYTES
#define CMA_SIZE_MBYTES CONFIG_CMA_SIZE_MBYTES
#else
#define CMA_SIZE_MBYTES 0
#endif
/*
* Default global CMA area size can be defined in kernel's .config.
* This is usefull mainly for distro maintainers to create a kernel
* that works correctly for most supported systems.
* The size can be set in bytes or as a percentage of the total memory
* in the system.
*
* Users, who want to set the size of global CMA area for their system
* should use cma= kernel parameter.
*/
static const unsigned long size_bytes = CMA_SIZE_MBYTES * SZ_1M;
static long size_cmdline = -1;
static int __init early_cma(char *p)
{
pr_debug("%s(%s)\n", __func__, p);
size_cmdline = memparse(p, &p);
return 0;
}
early_param("cma", early_cma);
#ifdef CONFIG_CMA_SIZE_PERCENTAGE
static unsigned long __init __maybe_unused cma_early_percent_memory(void)
{
struct memblock_region *reg;
unsigned long total_pages = 0;
/*
* We cannot use memblock_phys_mem_size() here, because
* memblock_analyze() has not been called yet.
*/
for_each_memblock(memory, reg)
total_pages += memblock_region_memory_end_pfn(reg) -
memblock_region_memory_base_pfn(reg);
return (total_pages * CONFIG_CMA_SIZE_PERCENTAGE / 100) << PAGE_SHIFT;
}
#else
static inline __maybe_unused unsigned long cma_early_percent_memory(void)
{
return 0;
}
#endif
/**
* dma_contiguous_reserve() - reserve area for contiguous memory handling
* @limit: End address of the reserved memory (optional, 0 for any).
*
* This function reserves memory from early allocator. It should be
* called by arch specific code once the early allocator (memblock or bootmem)
* has been activated and all other subsystems have already allocated/reserved
* memory.
*/
void __init dma_contiguous_reserve(phys_addr_t limit)
{
unsigned long selected_size = 0;
pr_debug("%s(limit %08lx)\n", __func__, (unsigned long)limit);
if (size_cmdline != -1) {
selected_size = size_cmdline;
} else {
#ifdef CONFIG_CMA_SIZE_SEL_MBYTES
selected_size = size_bytes;
#elif defined(CONFIG_CMA_SIZE_SEL_PERCENTAGE)
selected_size = cma_early_percent_memory();
#elif defined(CONFIG_CMA_SIZE_SEL_MIN)
selected_size = min(size_bytes, cma_early_percent_memory());
#elif defined(CONFIG_CMA_SIZE_SEL_MAX)
selected_size = max(size_bytes, cma_early_percent_memory());
#endif
}
if (selected_size) {
pr_debug("%s: reserving %ld MiB for global area\n", __func__,
selected_size / SZ_1M);
dma_declare_contiguous(NULL, selected_size, 0, limit);
}
};
static DEFINE_MUTEX(cma_mutex);
static __init int cma_activate_area(unsigned long base_pfn, unsigned long count)
{
unsigned long pfn = base_pfn;
unsigned i = count >> pageblock_order;
struct zone *zone;
WARN_ON_ONCE(!pfn_valid(pfn));
zone = page_zone(pfn_to_page(pfn));
do {
unsigned j;
base_pfn = pfn;
for (j = pageblock_nr_pages; j; --j, pfn++) {
WARN_ON_ONCE(!pfn_valid(pfn));
if (page_zone(pfn_to_page(pfn)) != zone)
return -EINVAL;
}
init_cma_reserved_pageblock(pfn_to_page(base_pfn));
} while (--i);
return 0;
}
static __init struct cma *cma_create_area(unsigned long base_pfn,
unsigned long count)
{
int bitmap_size = BITS_TO_LONGS(count) * sizeof(long);
struct cma *cma;
int ret = -ENOMEM;
pr_debug("%s(base %08lx, count %lx)\n", __func__, base_pfn, count);
cma = kmalloc(sizeof *cma, GFP_KERNEL);
if (!cma)
return ERR_PTR(-ENOMEM);
cma->base_pfn = base_pfn;
cma->count = count;
cma->bitmap = kzalloc(bitmap_size, GFP_KERNEL);
if (!cma->bitmap)
goto no_mem;
ret = cma_activate_area(base_pfn, count);
if (ret)
goto error;
pr_debug("%s: returned %p\n", __func__, (void *)cma);
return cma;
error:
kfree(cma->bitmap);
no_mem:
kfree(cma);
return ERR_PTR(ret);
}
static struct cma_reserved {
phys_addr_t start;
unsigned long size;
struct device *dev;
} cma_reserved[MAX_CMA_AREAS] __initdata;
static unsigned cma_reserved_count __initdata;
static int __init cma_init_reserved_areas(void)
{
struct cma_reserved *r = cma_reserved;
unsigned i = cma_reserved_count;
pr_debug("%s()\n", __func__);
for (; i; --i, ++r) {
struct cma *cma;
cma = cma_create_area(PFN_DOWN(r->start),
r->size >> PAGE_SHIFT);
if (!IS_ERR(cma))
dev_set_cma_area(r->dev, cma);
}
return 0;
}
core_initcall(cma_init_reserved_areas);
/**
* dma_declare_contiguous() - reserve area for contiguous memory handling
* for particular device
* @dev: Pointer to device structure.
* @size: Size of the reserved memory.
* @base: Start address of the reserved memory (optional, 0 for any).
* @limit: End address of the reserved memory (optional, 0 for any).
*
* This function reserves memory for specified device. It should be
* called by board specific code when early allocator (memblock or bootmem)
* is still activate.
*/
int __init dma_declare_contiguous(struct device *dev, unsigned long size,
phys_addr_t base, phys_addr_t limit)
{
struct cma_reserved *r = &cma_reserved[cma_reserved_count];
unsigned long alignment;
pr_debug("%s(size %lx, base %08lx, limit %08lx)\n", __func__,
(unsigned long)size, (unsigned long)base,
(unsigned long)limit);
/* Sanity checks */
if (cma_reserved_count == ARRAY_SIZE(cma_reserved)) {
pr_err("Not enough slots for CMA reserved regions!\n");
return -ENOSPC;
}
if (!size)
return -EINVAL;
/* Sanitise input arguments */
alignment = PAGE_SIZE << max(MAX_ORDER, pageblock_order);
base = ALIGN(base, alignment);
size = ALIGN(size, alignment);
limit &= ~(alignment - 1);
/* Reserve memory */
if (base) {
if (memblock_is_region_reserved(base, size) ||
memblock_reserve(base, size) < 0) {
base = -EBUSY;
goto err;
}
} else {
/*
* Use __memblock_alloc_base() since
* memblock_alloc_base() panic()s.
*/
phys_addr_t addr = __memblock_alloc_base(size, alignment, limit);
if (!addr) {
base = -ENOMEM;
goto err;
} else if (addr + size > ~(unsigned long)0) {
memblock_free(addr, size);
base = -EINVAL;
goto err;
} else {
base = addr;
}
}
/*
* Each reserved area must be initialised later, when more kernel
* subsystems (like slab allocator) are available.
*/
r->start = base;
r->size = size;
r->dev = dev;
cma_reserved_count++;
pr_info("CMA: reserved %ld MiB at %08lx\n", size / SZ_1M,
(unsigned long)base);
/* Architecture specific contiguous memory fixup. */
dma_contiguous_early_fixup(base, size);
return 0;
err:
pr_err("CMA: failed to reserve %ld MiB\n", size / SZ_1M);
return base;
}
/**
* dma_alloc_from_contiguous() - allocate pages from contiguous area
* @dev: Pointer to device for which the allocation is performed.
* @count: Requested number of pages.
* @align: Requested alignment of pages (in PAGE_SIZE order).
*
* This function allocates memory buffer for specified device. It uses
* device specific contiguous memory area if available or the default
* global one. Requires architecture specific get_dev_cma_area() helper
* function.
*/
struct page *dma_alloc_from_contiguous(struct device *dev, int count,
unsigned int align)
{
unsigned long mask, pfn, pageno, start = 0;
struct cma *cma = dev_get_cma_area(dev);
int ret;
if (!cma || !cma->count)
return NULL;
if (align > CONFIG_CMA_ALIGNMENT)
align = CONFIG_CMA_ALIGNMENT;
pr_debug("%s(cma %p, count %d, align %d)\n", __func__, (void *)cma,
count, align);
if (!count)
return NULL;
mask = (1 << align) - 1;
mutex_lock(&cma_mutex);
for (;;) {
pageno = bitmap_find_next_zero_area(cma->bitmap, cma->count,
start, count, mask);
if (pageno >= cma->count) {
ret = -ENOMEM;
goto error;
}
pfn = cma->base_pfn + pageno;
ret = alloc_contig_range(pfn, pfn + count, MIGRATE_CMA);
if (ret == 0) {
bitmap_set(cma->bitmap, pageno, count);
break;
} else if (ret != -EBUSY) {
goto error;
}
pr_debug("%s(): memory range at %p is busy, retrying\n",
__func__, pfn_to_page(pfn));
/* try again with a bit different memory target */
start = pageno + mask + 1;
}
mutex_unlock(&cma_mutex);
pr_debug("%s(): returned %p\n", __func__, pfn_to_page(pfn));
return pfn_to_page(pfn);
error:
mutex_unlock(&cma_mutex);
return NULL;
}
/**
* dma_release_from_contiguous() - release allocated pages
* @dev: Pointer to device for which the pages were allocated.
* @pages: Allocated pages.
* @count: Number of allocated pages.
*
* This function releases memory allocated by dma_alloc_from_contiguous().
* It returns false when provided pages do not belong to contiguous area and
* true otherwise.
*/
bool dma_release_from_contiguous(struct device *dev, struct page *pages,
int count)
{
struct cma *cma = dev_get_cma_area(dev);
unsigned long pfn;
if (!cma || !pages)
return false;
pr_debug("%s(page %p)\n", __func__, (void *)pages);
pfn = page_to_pfn(pages);
if (pfn < cma->base_pfn || pfn >= cma->base_pfn + cma->count)
return false;
VM_BUG_ON(pfn + count > cma->base_pfn + cma->count);
mutex_lock(&cma_mutex);
bitmap_clear(cma->bitmap, pfn - cma->base_pfn, count);
free_contig_range(pfn, count);
mutex_unlock(&cma_mutex);
return true;
}

4
include/asm-generic/dma-coherent.h
View file

@ -3,13 +3,15 @@
#ifdef CONFIG_HAVE_GENERIC_DMA_COHERENT
/*
* These two functions are only for dma allocator.
* These three functions are only for dma allocator.
* Don't use them in device drivers.
*/
int dma_alloc_from_coherent(struct device *dev, ssize_t size,
dma_addr_t *dma_handle, void **ret);
int dma_release_from_coherent(struct device *dev, int order, void *vaddr);
int dma_mmap_from_coherent(struct device *dev, struct vm_area_struct *vma,
void *cpu_addr, size_t size, int *ret);
/*
* Standard interface
*/

28
include/asm-generic/dma-contiguous.h Normal file
View file

@ -0,0 +1,28 @@
#ifndef ASM_DMA_CONTIGUOUS_H
#define ASM_DMA_CONTIGUOUS_H
#ifdef __KERNEL__
#ifdef CONFIG_CMA
#include <linux/device.h>
#include <linux/dma-contiguous.h>
static inline struct cma *dev_get_cma_area(struct device *dev)
{
if (dev && dev->cma_area)
return dev->cma_area;
return dma_contiguous_default_area;
}
static inline void dev_set_cma_area(struct device *dev, struct cma *cma)
{
if (dev)
dev->cma_area = cma;
if (!dev || !dma_contiguous_default_area)
dma_contiguous_default_area = cma;
}
#endif
#endif
#endif

4
include/linux/device.h
View file

@ -667,6 +667,10 @@ struct device {
struct dma_coherent_mem *dma_mem; /* internal for coherent mem
override */
#ifdef CONFIG_CMA
struct cma *cma_area; /* contiguous memory area for dma
allocations */
#endif
/* arch specific additions */
struct dev_archdata archdata;

110
include/linux/dma-contiguous.h Normal file
View file

@ -0,0 +1,110 @@
#ifndef __LINUX_CMA_H
#define __LINUX_CMA_H
/*
* Contiguous Memory Allocator for DMA mapping framework
* Copyright (c) 2010-2011 by Samsung Electronics.
* Written by:
* Marek Szyprowski <m.szyprowski@samsung.com>
* Michal Nazarewicz <mina86@mina86.com>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation; either version 2 of the
* License or (at your optional) any later version of the license.
*/
/*
* Contiguous Memory Allocator
*
* The Contiguous Memory Allocator (CMA) makes it possible to
* allocate big contiguous chunks of memory after the system has
* booted.
*
* Why is it needed?
*
* Various devices on embedded systems have no scatter-getter and/or
* IO map support and require contiguous blocks of memory to
* operate. They include devices such as cameras, hardware video
* coders, etc.
*
* Such devices often require big memory buffers (a full HD frame
* is, for instance, more then 2 mega pixels large, i.e. more than 6
* MB of memory), which makes mechanisms such as kmalloc() or
* alloc_page() ineffective.
*
* At the same time, a solution where a big memory region is
* reserved for a device is suboptimal since often more memory is
* reserved then strictly required and, moreover, the memory is
* inaccessible to page system even if device drivers don't use it.
*
* CMA tries to solve this issue by operating on memory regions
* where only movable pages can be allocated from. This way, kernel
* can use the memory for pagecache and when device driver requests
* it, allocated pages can be migrated.
*
* Driver usage
*
* CMA should not be used by the device drivers directly. It is
* only a helper framework for dma-mapping subsystem.
*
* For more information, see kernel-docs in drivers/base/dma-contiguous.c
*/
#ifdef __KERNEL__
struct cma;
struct page;
struct device;
#ifdef CONFIG_CMA
/*
* There is always at least global CMA area and a few optional device
* private areas configured in kernel .config.
*/
#define MAX_CMA_AREAS (1 + CONFIG_CMA_AREAS)
extern struct cma *dma_contiguous_default_area;
void dma_contiguous_reserve(phys_addr_t addr_limit);
int dma_declare_contiguous(struct device *dev, unsigned long size,
phys_addr_t base, phys_addr_t limit);
struct page *dma_alloc_from_contiguous(struct device *dev, int count,
unsigned int order);
bool dma_release_from_contiguous(struct device *dev, struct page *pages,
int count);
#else
#define MAX_CMA_AREAS (0)
static inline void dma_contiguous_reserve(phys_addr_t limit) { }
static inline
int dma_declare_contiguous(struct device *dev, unsigned long size,
phys_addr_t base, phys_addr_t limit)
{
return -ENOSYS;
}
static inline
struct page *dma_alloc_from_contiguous(struct device *dev, int count,
unsigned int order)
{
return NULL;
}
static inline
bool dma_release_from_contiguous(struct device *dev, struct page *pages,
int count)
{
return false;
}
#endif
#endif
#endif

12
include/linux/gfp.h
View file

@ -391,4 +391,16 @@ static inline bool pm_suspended_storage(void)
}
#endif /* CONFIG_PM_SLEEP */
#ifdef CONFIG_CMA
/* The below functions must be run on a range from a single zone. */
extern int alloc_contig_range(unsigned long start, unsigned long end,
unsigned migratetype);
extern void free_contig_range(unsigned long pfn, unsigned nr_pages);
/* CMA stuff */
extern void init_cma_reserved_pageblock(struct page *page);
#endif
#endif /* __LINUX_GFP_H */

47
include/linux/mmzone.h
View file

@ -35,13 +35,39 @@
*/
#define PAGE_ALLOC_COSTLY_ORDER 3
#define MIGRATE_UNMOVABLE 0
#define MIGRATE_RECLAIMABLE 1
#define MIGRATE_MOVABLE 2
#define MIGRATE_PCPTYPES 3 /* the number of types on the pcp lists */
#define MIGRATE_RESERVE 3
#define MIGRATE_ISOLATE 4 /* can't allocate from here */
#define MIGRATE_TYPES 5
enum {
MIGRATE_UNMOVABLE,
MIGRATE_RECLAIMABLE,
MIGRATE_MOVABLE,
MIGRATE_PCPTYPES, /* the number of types on the pcp lists */
MIGRATE_RESERVE = MIGRATE_PCPTYPES,
#ifdef CONFIG_CMA
/*
* MIGRATE_CMA migration type is designed to mimic the way
* ZONE_MOVABLE works. Only movable pages can be allocated
* from MIGRATE_CMA pageblocks and page allocator never
* implicitly change migration type of MIGRATE_CMA pageblock.
*
* The way to use it is to change migratetype of a range of
* pageblocks to MIGRATE_CMA which can be done by
* __free_pageblock_cma() function. What is important though
* is that a range of pageblocks must be aligned to
* MAX_ORDER_NR_PAGES should biggest page be bigger then
* a single pageblock.
*/
MIGRATE_CMA,
#endif
MIGRATE_ISOLATE, /* can't allocate from here */
MIGRATE_TYPES
};
#ifdef CONFIG_CMA
# define is_migrate_cma(migratetype) unlikely((migratetype) == MIGRATE_CMA)
# define cma_wmark_pages(zone) zone->min_cma_pages
#else
# define is_migrate_cma(migratetype) false
# define cma_wmark_pages(zone) 0
#endif
#define for_each_migratetype_order(order, type) \
for (order = 0; order < MAX_ORDER; order++) \
@ -346,6 +372,13 @@ struct zone {
#ifdef CONFIG_MEMORY_HOTPLUG
/* see spanned/present_pages for more description */
seqlock_t span_seqlock;
#endif
#ifdef CONFIG_CMA
/*
* CMA needs to increase watermark levels during the allocation
* process to make sure that the system is not starved.
*/
unsigned long min_cma_pages;
#endif
struct free_area free_area[MAX_ORDER];

18
include/linux/page-isolation.h
View file

@ -3,7 +3,7 @@
/*
* Changes migrate type in [start_pfn, end_pfn) to be MIGRATE_ISOLATE.
* If specified range includes migrate types other than MOVABLE,
* If specified range includes migrate types other than MOVABLE or CMA,
* this will fail with -EBUSY.
*
* For isolating all pages in the range finally, the caller have to
@ -11,27 +11,27 @@
* test it.
*/
extern int
start_isolate_page_range(unsigned long start_pfn, unsigned long end_pfn);
start_isolate_page_range(unsigned long start_pfn, unsigned long end_pfn,
unsigned migratetype);
/*
* Changes MIGRATE_ISOLATE to MIGRATE_MOVABLE.
* target range is [start_pfn, end_pfn)
*/
extern int
undo_isolate_page_range(unsigned long start_pfn, unsigned long end_pfn);
undo_isolate_page_range(unsigned long start_pfn, unsigned long end_pfn,
unsigned migratetype);
/*
* test all pages in [start_pfn, end_pfn)are isolated or not.
* Test all pages in [start_pfn, end_pfn) are isolated or not.
*/
extern int
test_pages_isolated(unsigned long start_pfn, unsigned long end_pfn);
int test_pages_isolated(unsigned long start_pfn, unsigned long end_pfn);
/*
* Internal funcs.Changes pageblock's migrate type.
* Please use make_pagetype_isolated()/make_pagetype_movable().
* Internal functions. Changes pageblock's migrate type.
*/
extern int set_migratetype_isolate(struct page *page);
extern void unset_migratetype_isolate(struct page *page);
extern void unset_migratetype_isolate(struct page *page, unsigned migratetype);
#endif

2
mm/Kconfig
View file

@ -198,7 +198,7 @@ config COMPACTION
config MIGRATION
bool "Page migration"
def_bool y
depends on NUMA || ARCH_ENABLE_MEMORY_HOTREMOVE || COMPACTION
depends on NUMA || ARCH_ENABLE_MEMORY_HOTREMOVE || COMPACTION || CMA
help
Allows the migration of the physical location of pages of processes
while the virtual addresses are not changed. This is useful in

3
mm/Makefile
View file

@ -13,7 +13,7 @@ obj-y := filemap.o mempool.o oom_kill.o fadvise.o \
readahead.o swap.o truncate.o vmscan.o shmem.o \
prio_tree.o util.o mmzone.o vmstat.o backing-dev.o \
page_isolation.o mm_init.o mmu_context.o percpu.o \
$(mmu-y)
compaction.o $(mmu-y)
obj-y += init-mm.o
ifdef CONFIG_NO_BOOTMEM
@ -32,7 +32,6 @@ obj-$(CONFIG_NUMA) += mempolicy.o
obj-$(CONFIG_SPARSEMEM) += sparse.o
obj-$(CONFIG_SPARSEMEM_VMEMMAP) += sparse-vmemmap.o
obj-$(CONFIG_SLOB) += slob.o
obj-$(CONFIG_COMPACTION) += compaction.o
obj-$(CONFIG_MMU_NOTIFIER) += mmu_notifier.o
obj-$(CONFIG_KSM) += ksm.o
obj-$(CONFIG_PAGE_POISONING) += debug-pagealloc.o

420
mm/compaction.c
View file

@ -16,30 +16,11 @@
#include <linux/sysfs.h>
#include "internal.h"
#if defined CONFIG_COMPACTION || defined CONFIG_CMA
#define CREATE_TRACE_POINTS
#include <trace/events/compaction.h>
/*
* compact_control is used to track pages being migrated and the free pages
* they are being migrated to during memory compaction. The free_pfn starts
* at the end of a zone and migrate_pfn begins at the start. Movable pages
* are moved to the end of a zone during a compaction run and the run
* completes when free_pfn <= migrate_pfn
*/
struct compact_control {
struct list_head freepages; /* List of free pages to migrate to */
struct list_head migratepages; /* List of pages being migrated */
unsigned long nr_freepages; /* Number of isolated free pages */
unsigned long nr_migratepages; /* Number of pages to migrate */
unsigned long free_pfn; /* isolate_freepages search base */
unsigned long migrate_pfn; /* isolate_migratepages search base */
bool sync; /* Synchronous migration */
int order; /* order a direct compactor needs */
int migratetype; /* MOVABLE, RECLAIMABLE etc */
struct zone *zone;
};
static unsigned long release_freepages(struct list_head *freelist)
{
struct page *page, *next;
@ -54,24 +35,35 @@ static unsigned long release_freepages(struct list_head *freelist)
return count;
}
/* Isolate free pages onto a private freelist. Must hold zone->lock */
static unsigned long isolate_freepages_block(struct zone *zone,
unsigned long blockpfn,
struct list_head *freelist)
static void map_pages(struct list_head *list)
{
struct page *page;
list_for_each_entry(page, list, lru) {
arch_alloc_page(page, 0);
kernel_map_pages(page, 1, 1);
}
}
static inline bool migrate_async_suitable(int migratetype)
{
return is_migrate_cma(migratetype) || migratetype == MIGRATE_MOVABLE;
}
/*
* Isolate free pages onto a private freelist. Caller must hold zone->lock.
* If @strict is true, will abort returning 0 on any invalid PFNs or non-free
* pages inside of the pageblock (even though it may still end up isolating
* some pages).
*/
static unsigned long isolate_freepages_block(unsigned long blockpfn,
unsigned long end_pfn,
struct list_head *freelist,
bool strict)
{
unsigned long zone_end_pfn, end_pfn;
int nr_scanned = 0, total_isolated = 0;
struct page *cursor;
/* Get the last PFN we should scan for free pages at */
zone_end_pfn = zone->zone_start_pfn + zone->spanned_pages;
end_pfn = min(blockpfn + pageblock_nr_pages, zone_end_pfn);
/* Find the first usable PFN in the block to initialse page cursor */
for (; blockpfn < end_pfn; blockpfn++) {
if (pfn_valid_within(blockpfn))
break;
}
cursor = pfn_to_page(blockpfn);
/* Isolate free pages. This assumes the block is valid */
@ -79,15 +71,23 @@ static unsigned long isolate_freepages_block(struct zone *zone,
int isolated, i;
struct page *page = cursor;
if (!pfn_valid_within(blockpfn))
if (!pfn_valid_within(blockpfn)) {
if (strict)
return 0;
continue;
}
nr_scanned++;
if (!PageBuddy(page))
if (!PageBuddy(page)) {
if (strict)
return 0;
continue;
}
/* Found a free page, break it into order-0 pages */
isolated = split_free_page(page);
if (!isolated && strict)
return 0;
total_isolated += isolated;
for (i = 0; i < isolated; i++) {
list_add(&page->lru, freelist);
@ -105,114 +105,71 @@ static unsigned long isolate_freepages_block(struct zone *zone,
return total_isolated;
}
/* Returns true if the page is within a block suitable for migration to */
static bool suitable_migration_target(struct page *page)
{
int migratetype = get_pageblock_migratetype(page);
/* Don't interfere with memory hot-remove or the min_free_kbytes blocks */
if (migratetype == MIGRATE_ISOLATE || migratetype == MIGRATE_RESERVE)
return false;
/* If the page is a large free page, then allow migration */
if (PageBuddy(page) && page_order(page) >= pageblock_order)
return true;
/* If the block is MIGRATE_MOVABLE, allow migration */
if (migratetype == MIGRATE_MOVABLE)
return true;
/* Otherwise skip the block */
return false;
}
/*
* Based on information in the current compact_control, find blocks
* suitable for isolating free pages from and then isolate them.
/**
* isolate_freepages_range() - isolate free pages.
* @start_pfn: The first PFN to start isolating.
* @end_pfn: The one-past-last PFN.
*
* Non-free pages, invalid PFNs, or zone boundaries within the
* [start_pfn, end_pfn) range are considered errors, cause function to
* undo its actions and return zero.
*
* Otherwise, function returns one-past-the-last PFN of isolated page
* (which may be greater then end_pfn if end fell in a middle of
* a free page).
*/
static void isolate_freepages(struct zone *zone,
struct compact_control *cc)
unsigned long
isolate_freepages_range(unsigned long start_pfn, unsigned long end_pfn)
{
struct page *page;
unsigned long high_pfn, low_pfn, pfn;
unsigned long flags;
int nr_freepages = cc->nr_freepages;
struct list_head *freelist = &cc->freepages;
unsigned long isolated, pfn, block_end_pfn, flags;
struct zone *zone = NULL;
LIST_HEAD(freelist);
/*
* Initialise the free scanner. The starting point is where we last
* scanned from (or the end of the zone if starting). The low point
* is the end of the pageblock the migration scanner is using.
*/
pfn = cc->free_pfn;
low_pfn = cc->migrate_pfn + pageblock_nr_pages;
if (pfn_valid(start_pfn))
zone = page_zone(pfn_to_page(start_pfn));
/*
* Take care that if the migration scanner is at the end of the zone
* that the free scanner does not accidentally move to the next zone
* in the next isolation cycle.
*/
high_pfn = min(low_pfn, pfn);
/*
* Isolate free pages until enough are available to migrate the
* pages on cc->migratepages. We stop searching if the migrate
* and free page scanners meet or enough free pages are isolated.
*/
for (; pfn > low_pfn && cc->nr_migratepages > nr_freepages;
pfn -= pageblock_nr_pages) {
unsigned long isolated;
if (!pfn_valid(pfn))
continue;
for (pfn = start_pfn; pfn < end_pfn; pfn += isolated) {
if (!pfn_valid(pfn) || zone != page_zone(pfn_to_page(pfn)))
break;
/*
* Check for overlapping nodes/zones. It's possible on some
* configurations to have a setup like
* node0 node1 node0
* i.e. it's possible that all pages within a zones range of
* pages do not belong to a single zone.
* On subsequent iterations ALIGN() is actually not needed,
* but we keep it that we not to complicate the code.
*/
page = pfn_to_page(pfn);
if (page_zone(page) != zone)
continue;
block_end_pfn = ALIGN(pfn + 1, pageblock_nr_pages);
block_end_pfn = min(block_end_pfn, end_pfn);
/* Check the block is suitable for migration */
if (!suitable_migration_target(page))
continue;
/*
* Found a block suitable for isolating free pages from. Now
* we disabled interrupts, double check things are ok and
* isolate the pages. This is to minimise the time IRQs
* are disabled
*/
isolated = 0;
spin_lock_irqsave(&zone->lock, flags);
if (suitable_migration_target(page)) {
isolated = isolate_freepages_block(zone, pfn, freelist);
nr_freepages += isolated;
}
isolated = isolate_freepages_block(pfn, block_end_pfn,
&freelist, true);
spin_unlock_irqrestore(&zone->lock, flags);
/*
* Record the highest PFN we isolated pages from. When next
* looking for free pages, the search will restart here as
* page migration may have returned some pages to the allocator
* In strict mode, isolate_freepages_block() returns 0 if
* there are any holes in the block (ie. invalid PFNs or
* non-free pages).
*/
if (!isolated)
break;
/*
* If we managed to isolate pages, it is always (1 << n) *
* pageblock_nr_pages for some non-negative n. (Max order
* page may span two pageblocks).
*/
if (isolated)
high_pfn = max(high_pfn, pfn);
}
/* split_free_page does not map the pages */
list_for_each_entry(page, freelist, lru) {
arch_alloc_page(page, 0);
kernel_map_pages(page, 1, 1);
map_pages(&freelist);
if (pfn < end_pfn) {
/* Loop terminated early, cleanup. */
release_freepages(&freelist);
return 0;
}
cc->free_pfn = high_pfn;
cc->nr_freepages = nr_freepages;
/* We don't use freelists for anything. */
return pfn;
}
/* Update the number of anon and file isolated pages in the zone */
@ -243,38 +200,34 @@ static bool too_many_isolated(struct zone *zone)
return isolated > (inactive + active) / 2;
}
/* possible outcome of isolate_migratepages */
typedef enum {
ISOLATE_ABORT, /* Abort compaction now */
ISOLATE_NONE, /* No pages isolated, continue scanning */
ISOLATE_SUCCESS, /* Pages isolated, migrate */
} isolate_migrate_t;
/*
* Isolate all pages that can be migrated from the block pointed to by
* the migrate scanner within compact_control.
/**
* isolate_migratepages_range() - isolate all migrate-able pages in range.
* @zone: Zone pages are in.
* @cc: Compaction control structure.
* @low_pfn: The first PFN of the range.
* @end_pfn: The one-past-the-last PFN of the range.
*
* Isolate all pages that can be migrated from the range specified by
* [low_pfn, end_pfn). Returns zero if there is a fatal signal
* pending), otherwise PFN of the first page that was not scanned
* (which may be both less, equal to or more then end_pfn).
*
* Assumes that cc->migratepages is empty and cc->nr_migratepages is
* zero.
*
* Apart from cc->migratepages and cc->nr_migratetypes this function
* does not modify any cc's fields, in particular it does not modify
* (or read for that matter) cc->migrate_pfn.
*/
static isolate_migrate_t isolate_migratepages(struct zone *zone,
struct compact_control *cc)
unsigned long
isolate_migratepages_range(struct zone *zone, struct compact_control *cc,
unsigned long low_pfn, unsigned long end_pfn)
{
unsigned long low_pfn, end_pfn;
unsigned long last_pageblock_nr = 0, pageblock_nr;
unsigned long nr_scanned = 0, nr_isolated = 0;
struct list_head *migratelist = &cc->migratepages;
isolate_mode_t mode = ISOLATE_ACTIVE|ISOLATE_INACTIVE;
/* Do not scan outside zone boundaries */
low_pfn = max(cc->migrate_pfn, zone->zone_start_pfn);
/* Only scan within a pageblock boundary */
end_pfn = ALIGN(low_pfn + pageblock_nr_pages, pageblock_nr_pages);
/* Do not cross the free scanner or scan within a memory hole */
if (end_pfn > cc->free_pfn || !pfn_valid(low_pfn)) {
cc->migrate_pfn = end_pfn;
return ISOLATE_NONE;
}
/*
* Ensure that there are not too many pages isolated from the LRU
* list by either parallel reclaimers or compaction. If there are,
@ -283,12 +236,12 @@ static isolate_migrate_t isolate_migratepages(struct zone *zone,
while (unlikely(too_many_isolated(zone))) {
/* async migration should just abort */
if (!cc->sync)
return ISOLATE_ABORT;
return 0;
congestion_wait(BLK_RW_ASYNC, HZ/10);
if (fatal_signal_pending(current))
return ISOLATE_ABORT;
return 0;
}
/* Time to isolate some pages for migration */
@ -351,7 +304,7 @@ static isolate_migrate_t isolate_migratepages(struct zone *zone,
*/
pageblock_nr = low_pfn >> pageblock_order;
if (!cc->sync && last_pageblock_nr != pageblock_nr &&
get_pageblock_migratetype(page) != MIGRATE_MOVABLE) {
!migrate_async_suitable(get_pageblock_migratetype(page))) {
low_pfn += pageblock_nr_pages;
low_pfn = ALIGN(low_pfn, pageblock_nr_pages) - 1;
last_pageblock_nr = pageblock_nr;
@ -396,11 +349,124 @@ static isolate_migrate_t isolate_migratepages(struct zone *zone,
acct_isolated(zone, cc);
spin_unlock_irq(&zone->lru_lock);
cc->migrate_pfn = low_pfn;
trace_mm_compaction_isolate_migratepages(nr_scanned, nr_isolated);
return ISOLATE_SUCCESS;
return low_pfn;
}
#endif /* CONFIG_COMPACTION || CONFIG_CMA */
#ifdef CONFIG_COMPACTION
/* Returns true if the page is within a block suitable for migration to */
static bool suitable_migration_target(struct page *page)
{
int migratetype = get_pageblock_migratetype(page);
/* Don't interfere with memory hot-remove or the min_free_kbytes blocks */
if (migratetype == MIGRATE_ISOLATE || migratetype == MIGRATE_RESERVE)
return false;
/* If the page is a large free page, then allow migration */
if (PageBuddy(page) && page_order(page) >= pageblock_order)
return true;
/* If the block is MIGRATE_MOVABLE or MIGRATE_CMA, allow migration */
if (migrate_async_suitable(migratetype))
return true;
/* Otherwise skip the block */
return false;
}
/*
* Based on information in the current compact_control, find blocks
* suitable for isolating free pages from and then isolate them.
*/
static void isolate_freepages(struct zone *zone,
struct compact_control *cc)
{
struct page *page;
unsigned long high_pfn, low_pfn, pfn, zone_end_pfn, end_pfn;
unsigned long flags;
int nr_freepages = cc->nr_freepages;
struct list_head *freelist = &cc->freepages;
/*
* Initialise the free scanner. The starting point is where we last
* scanned from (or the end of the zone if starting). The low point
* is the end of the pageblock the migration scanner is using.
*/
pfn = cc->free_pfn;
low_pfn = cc->migrate_pfn + pageblock_nr_pages;
/*
* Take care that if the migration scanner is at the end of the zone
* that the free scanner does not accidentally move to the next zone
* in the next isolation cycle.
*/
high_pfn = min(low_pfn, pfn);
zone_end_pfn = zone->zone_start_pfn + zone->spanned_pages;
/*
* Isolate free pages until enough are available to migrate the
* pages on cc->migratepages. We stop searching if the migrate
* and free page scanners meet or enough free pages are isolated.
*/
for (; pfn > low_pfn && cc->nr_migratepages > nr_freepages;
pfn -= pageblock_nr_pages) {
unsigned long isolated;
if (!pfn_valid(pfn))
continue;
/*
* Check for overlapping nodes/zones. It's possible on some
* configurations to have a setup like
* node0 node1 node0
* i.e. it's possible that all pages within a zones range of
* pages do not belong to a single zone.
*/
page = pfn_to_page(pfn);
if (page_zone(page) != zone)
continue;
/* Check the block is suitable for migration */
if (!suitable_migration_target(page))
continue;
/*
* Found a block suitable for isolating free pages from. Now
* we disabled interrupts, double check things are ok and
* isolate the pages. This is to minimise the time IRQs
* are disabled
*/
isolated = 0;
spin_lock_irqsave(&zone->lock, flags);
if (suitable_migration_target(page)) {
end_pfn = min(pfn + pageblock_nr_pages, zone_end_pfn);
isolated = isolate_freepages_block(pfn, end_pfn,
freelist, false);
nr_freepages += isolated;
}
spin_unlock_irqrestore(&zone->lock, flags);
/*
* Record the highest PFN we isolated pages from. When next
* looking for free pages, the search will restart here as
* page migration may have returned some pages to the allocator
*/
if (isolated)
high_pfn = max(high_pfn, pfn);
}
/* split_free_page does not map the pages */
map_pages(freelist);
cc->free_pfn = high_pfn;
cc->nr_freepages = nr_freepages;
}
/*
@ -449,6 +515,44 @@ static void update_nr_listpages(struct compact_control *cc)
cc->nr_freepages = nr_freepages;
}
/* possible outcome of isolate_migratepages */
typedef enum {
ISOLATE_ABORT, /* Abort compaction now */
ISOLATE_NONE, /* No pages isolated, continue scanning */
ISOLATE_SUCCESS, /* Pages isolated, migrate */
} isolate_migrate_t;
/*
* Isolate all pages that can be migrated from the block pointed to by
* the migrate scanner within compact_control.
*/
static isolate_migrate_t isolate_migratepages(struct zone *zone,
struct compact_control *cc)
{
unsigned long low_pfn, end_pfn;
/* Do not scan outside zone boundaries */
low_pfn = max(cc->migrate_pfn, zone->zone_start_pfn);
/* Only scan within a pageblock boundary */
end_pfn = ALIGN(low_pfn + pageblock_nr_pages, pageblock_nr_pages);
/* Do not cross the free scanner or scan within a memory hole */
if (end_pfn > cc->free_pfn || !pfn_valid(low_pfn)) {
cc->migrate_pfn = end_pfn;
return ISOLATE_NONE;
}
/* Perform the isolation */
low_pfn = isolate_migratepages_range(zone, cc, low_pfn, end_pfn);
if (!low_pfn)
return ISOLATE_ABORT;
cc->migrate_pfn = low_pfn;
return ISOLATE_SUCCESS;
}
static int compact_finished(struct zone *zone,
struct compact_control *cc)
{
@ -795,3 +899,5 @@ void compaction_unregister_node(struct node *node)
return device_remove_file(&node->dev, &dev_attr_compact);
}
#endif /* CONFIG_SYSFS && CONFIG_NUMA */
#endif /* CONFIG_COMPACTION */

33
mm/internal.h
View file

@ -100,6 +100,39 @@ extern void prep_compound_page(struct page *page, unsigned long order);
extern bool is_free_buddy_page(struct page *page);
#endif
#if defined CONFIG_COMPACTION || defined CONFIG_CMA
/*
* in mm/compaction.c
*/
/*
* compact_control is used to track pages being migrated and the free pages
* they are being migrated to during memory compaction. The free_pfn starts
* at the end of a zone and migrate_pfn begins at the start. Movable pages
* are moved to the end of a zone during a compaction run and the run
* completes when free_pfn <= migrate_pfn
*/
struct compact_control {
struct list_head freepages; /* List of free pages to migrate to */
struct list_head migratepages; /* List of pages being migrated */
unsigned long nr_freepages; /* Number of isolated free pages */
unsigned long nr_migratepages; /* Number of pages to migrate */
unsigned long free_pfn; /* isolate_freepages search base */
unsigned long migrate_pfn; /* isolate_migratepages search base */
bool sync; /* Synchronous migration */
int order; /* order a direct compactor needs */
int migratetype; /* MOVABLE, RECLAIMABLE etc */
struct zone *zone;
};
unsigned long
isolate_freepages_range(unsigned long start_pfn, unsigned long end_pfn);
unsigned long
isolate_migratepages_range(struct zone *zone, struct compact_control *cc,
unsigned long low_pfn, unsigned long end_pfn);
#endif
/*
* function for dealing with page's order in buddy system.

2
mm/memory-failure.c
View file

@ -1404,7 +1404,7 @@ static int get_any_page(struct page *p, unsigned long pfn, int flags)
/* Not a free page */
ret = 1;
}
unset_migratetype_isolate(p);
unset_migratetype_isolate(p, MIGRATE_MOVABLE);
unlock_memory_hotplug();
return ret;
}

6
mm/memory_hotplug.c
View file

@ -891,7 +891,7 @@ static int __ref offline_pages(unsigned long start_pfn,
nr_pages = end_pfn - start_pfn;
/* set above range as isolated */
ret = start_isolate_page_range(start_pfn, end_pfn);
ret = start_isolate_page_range(start_pfn, end_pfn, MIGRATE_MOVABLE);
if (ret)
goto out;
@ -956,7 +956,7 @@ repeat:
We cannot do rollback at this point. */
offline_isolated_pages(start_pfn, end_pfn);
/* reset pagetype flags and makes migrate type to be MOVABLE */
undo_isolate_page_range(start_pfn, end_pfn);
undo_isolate_page_range(start_pfn, end_pfn, MIGRATE_MOVABLE);
/* removal success */
zone->present_pages -= offlined_pages;
zone->zone_pgdat->node_present_pages -= offlined_pages;
@ -981,7 +981,7 @@ failed_removal:
start_pfn, end_pfn);
memory_notify(MEM_CANCEL_OFFLINE, &arg);
/* pushback to free area */
undo_isolate_page_range(start_pfn, end_pfn);
undo_isolate_page_range(start_pfn, end_pfn, MIGRATE_MOVABLE);
out:
unlock_memory_hotplug();

409
mm/page_alloc.c
View file

@ -57,6 +57,7 @@
#include <linux/ftrace_event.h>
#include <linux/memcontrol.h>
#include <linux/prefetch.h>
#include <linux/migrate.h>
#include <linux/page-debug-flags.h>
#include <asm/tlbflush.h>
@ -513,10 +514,10 @@ static inline int page_is_buddy(struct page *page, struct page *buddy,
* free pages of length of (1 << order) and marked with _mapcount -2. Page's
* order is recorded in page_private(page) field.
* So when we are allocating or freeing one, we can derive the state of the
* other. That is, if we allocate a small block, and both were
* free, the remainder of the region must be split into blocks.
* other. That is, if we allocate a small block, and both were
* free, the remainder of the region must be split into blocks.
* If a block is freed, and its buddy is also free, then this
* triggers coalescing into a block of larger size.
* triggers coalescing into a block of larger size.
*
* -- wli
*/
@ -749,6 +750,24 @@ void __meminit __free_pages_bootmem(struct page *page, unsigned int order)
__free_pages(page, order);
}
#ifdef CONFIG_CMA
/* Free whole pageblock and set it's migration type to MIGRATE_CMA. */
void __init init_cma_reserved_pageblock(struct page *page)
{
unsigned i = pageblock_nr_pages;
struct page *p = page;
do {
__ClearPageReserved(p);
set_page_count(p, 0);
} while (++p, --i);
set_page_refcounted(page);
set_pageblock_migratetype(page, MIGRATE_CMA);
__free_pages(page, pageblock_order);
totalram_pages += pageblock_nr_pages;
}
#endif
/*
* The order of subdivision here is critical for the IO subsystem.
@ -874,11 +893,17 @@ struct page *__rmqueue_smallest(struct zone *zone, unsigned int order,
* This array describes the order lists are fallen back to when
* the free lists for the desirable migrate type are depleted
*/
static int fallbacks[MIGRATE_TYPES][MIGRATE_TYPES-1] = {
[MIGRATE_UNMOVABLE] = { MIGRATE_RECLAIMABLE, MIGRATE_MOVABLE, MIGRATE_RESERVE },
[MIGRATE_RECLAIMABLE] = { MIGRATE_UNMOVABLE, MIGRATE_MOVABLE, MIGRATE_RESERVE },
[MIGRATE_MOVABLE] = { MIGRATE_RECLAIMABLE, MIGRATE_UNMOVABLE, MIGRATE_RESERVE },
[MIGRATE_RESERVE] = { MIGRATE_RESERVE, MIGRATE_RESERVE, MIGRATE_RESERVE }, /* Never used */
static int fallbacks[MIGRATE_TYPES][4] = {
[MIGRATE_UNMOVABLE] = { MIGRATE_RECLAIMABLE, MIGRATE_MOVABLE, MIGRATE_RESERVE },
[MIGRATE_RECLAIMABLE] = { MIGRATE_UNMOVABLE, MIGRATE_MOVABLE, MIGRATE_RESERVE },
#ifdef CONFIG_CMA
[MIGRATE_MOVABLE] = { MIGRATE_CMA, MIGRATE_RECLAIMABLE, MIGRATE_UNMOVABLE, MIGRATE_RESERVE },
[MIGRATE_CMA] = { MIGRATE_RESERVE }, /* Never used */
#else
[MIGRATE_MOVABLE] = { MIGRATE_RECLAIMABLE, MIGRATE_UNMOVABLE, MIGRATE_RESERVE },
#endif
[MIGRATE_RESERVE] = { MIGRATE_RESERVE }, /* Never used */
[MIGRATE_ISOLATE] = { MIGRATE_RESERVE }, /* Never used */
};
/*
@ -973,12 +998,12 @@ __rmqueue_fallback(struct zone *zone, int order, int start_migratetype)
/* Find the largest possible block of pages in the other list */
for (current_order = MAX_ORDER-1; current_order >= order;
--current_order) {
for (i = 0; i < MIGRATE_TYPES - 1; i++) {
for (i = 0;; i++) {
migratetype = fallbacks[start_migratetype][i];
/* MIGRATE_RESERVE handled later if necessary */
if (migratetype == MIGRATE_RESERVE)
continue;
break;
area = &(zone->free_area[current_order]);
if (list_empty(&area->free_list[migratetype]))
@ -993,11 +1018,18 @@ __rmqueue_fallback(struct zone *zone, int order, int start_migratetype)
* pages to the preferred allocation list. If falling
* back for a reclaimable kernel allocation, be more
* aggressive about taking ownership of free pages
*
* On the other hand, never change migration
* type of MIGRATE_CMA pageblocks nor move CMA
* pages on different free lists. We don't
* want unmovable pages to be allocated from
* MIGRATE_CMA areas.
*/
if (unlikely(current_order >= (pageblock_order >> 1)) ||
start_migratetype == MIGRATE_RECLAIMABLE ||
page_group_by_mobility_disabled) {
unsigned long pages;
if (!is_migrate_cma(migratetype) &&
(unlikely(current_order >= pageblock_order / 2) ||
start_migratetype == MIGRATE_RECLAIMABLE ||
page_group_by_mobility_disabled)) {
int pages;
pages = move_freepages_block(zone, page,
start_migratetype);
@ -1015,11 +1047,14 @@ __rmqueue_fallback(struct zone *zone, int order, int start_migratetype)
rmv_page_order(page);
/* Take ownership for orders >= pageblock_order */
if (current_order >= pageblock_order)
if (current_order >= pageblock_order &&
!is_migrate_cma(migratetype))
change_pageblock_range(page, current_order,
start_migratetype);
expand(zone, page, order, current_order, area, migratetype);
expand(zone, page, order, current_order, area,
is_migrate_cma(migratetype)
? migratetype : start_migratetype);
trace_mm_page_alloc_extfrag(page, order, current_order,
start_migratetype, migratetype);
@ -1061,17 +1096,17 @@ retry_reserve:
return page;
}
/*
/*
* Obtain a specified number of elements from the buddy allocator, all under
* a single hold of the lock, for efficiency. Add them to the supplied list.
* Returns the number of new pages which were placed at *list.
*/
static int rmqueue_bulk(struct zone *zone, unsigned int order,
static int rmqueue_bulk(struct zone *zone, unsigned int order,
unsigned long count, struct list_head *list,
int migratetype, int cold)
{
int i;
int mt = migratetype, i;
spin_lock(&zone->lock);
for (i = 0; i < count; ++i) {
struct page *page = __rmqueue(zone, order, migratetype);
@ -1091,7 +1126,12 @@ static int rmqueue_bulk(struct zone *zone, unsigned int order,
list_add(&page->lru, list);
else
list_add_tail(&page->lru, list);
set_page_private(page, migratetype);
if (IS_ENABLED(CONFIG_CMA)) {
mt = get_pageblock_migratetype(page);
if (!is_migrate_cma(mt) && mt != MIGRATE_ISOLATE)
mt = migratetype;
}
set_page_private(page, mt);
list = &page->lru;
}
__mod_zone_page_state(zone, NR_FREE_PAGES, -(i << order));
@ -1371,8 +1411,12 @@ int split_free_page(struct page *page)
if (order >= pageblock_order - 1) {
struct page *endpage = page + (1 << order) - 1;
for (; page < endpage; page += pageblock_nr_pages)
set_pageblock_migratetype(page, MIGRATE_MOVABLE);
for (; page < endpage; page += pageblock_nr_pages) {
int mt = get_pageblock_migratetype(page);
if (mt != MIGRATE_ISOLATE && !is_migrate_cma(mt))
set_pageblock_migratetype(page,
MIGRATE_MOVABLE);
}
}
return 1 << order;
@ -2086,16 +2130,13 @@ __alloc_pages_direct_compact(gfp_t gfp_mask, unsigned int order,
}
#endif /* CONFIG_COMPACTION */
/* The really slow allocator path where we enter direct reclaim */
static inline struct page *
__alloc_pages_direct_reclaim(gfp_t gfp_mask, unsigned int order,
struct zonelist *zonelist, enum zone_type high_zoneidx,
nodemask_t *nodemask, int alloc_flags, struct zone *preferred_zone,
int migratetype, unsigned long *did_some_progress)
/* Perform direct synchronous page reclaim */
static int
__perform_reclaim(gfp_t gfp_mask, unsigned int order, struct zonelist *zonelist,
nodemask_t *nodemask)
{
struct page *page = NULL;
struct reclaim_state reclaim_state;
bool drained = false;
int progress;
cond_resched();
@ -2106,7 +2147,7 @@ __alloc_pages_direct_reclaim(gfp_t gfp_mask, unsigned int order,
reclaim_state.reclaimed_slab = 0;
current->reclaim_state = &reclaim_state;
*did_some_progress = try_to_free_pages(zonelist, order, gfp_mask, nodemask);
progress = try_to_free_pages(zonelist, order, gfp_mask, nodemask);
current->reclaim_state = NULL;
lockdep_clear_current_reclaim_state();
@ -2114,6 +2155,21 @@ __alloc_pages_direct_reclaim(gfp_t gfp_mask, unsigned int order,
cond_resched();
return progress;
}
/* The really slow allocator path where we enter direct reclaim */
static inline struct page *
__alloc_pages_direct_reclaim(gfp_t gfp_mask, unsigned int order,
struct zonelist *zonelist, enum zone_type high_zoneidx,
nodemask_t *nodemask, int alloc_flags, struct zone *preferred_zone,
int migratetype, unsigned long *did_some_progress)
{
struct page *page = NULL;
bool drained = false;
*did_some_progress = __perform_reclaim(gfp_mask, order, zonelist,
nodemask);
if (unlikely(!(*did_some_progress)))
return NULL;
@ -4301,7 +4357,7 @@ static void __paginginit free_area_init_core(struct pglist_data *pgdat,
init_waitqueue_head(&pgdat->kswapd_wait);
pgdat->kswapd_max_order = 0;
pgdat_page_cgroup_init(pgdat);
for (j = 0; j < MAX_NR_ZONES; j++) {
struct zone *zone = pgdat->node_zones + j;
unsigned long size, realsize, memmap_pages;
@ -4976,14 +5032,7 @@ static void setup_per_zone_lowmem_reserve(void)
calculate_totalreserve_pages();
}
/**
* setup_per_zone_wmarks - called when min_free_kbytes changes
* or when memory is hot-{added|removed}
*
* Ensures that the watermark[min,low,high] values for each zone are set
* correctly with respect to min_free_kbytes.
*/
void setup_per_zone_wmarks(void)
static void __setup_per_zone_wmarks(void)
{
unsigned long pages_min = min_free_kbytes >> (PAGE_SHIFT - 10);
unsigned long lowmem_pages = 0;
@ -5030,6 +5079,11 @@ void setup_per_zone_wmarks(void)
zone->watermark[WMARK_LOW] = min_wmark_pages(zone) + (tmp >> 2);
zone->watermark[WMARK_HIGH] = min_wmark_pages(zone) + (tmp >> 1);
zone->watermark[WMARK_MIN] += cma_wmark_pages(zone);
zone->watermark[WMARK_LOW] += cma_wmark_pages(zone);
zone->watermark[WMARK_HIGH] += cma_wmark_pages(zone);
setup_zone_migrate_reserve(zone);
spin_unlock_irqrestore(&zone->lock, flags);
}
@ -5038,6 +5092,20 @@ void setup_per_zone_wmarks(void)
calculate_totalreserve_pages();
}
/**
* setup_per_zone_wmarks - called when min_free_kbytes changes
* or when memory is hot-{added|removed}
*
* Ensures that the watermark[min,low,high] values for each zone are set
* correctly with respect to min_free_kbytes.
*/
void setup_per_zone_wmarks(void)
{
mutex_lock(&zonelists_mutex);
__setup_per_zone_wmarks();
mutex_unlock(&zonelists_mutex);
}
/*
* The inactive anon list should be small enough that the VM never has to
* do too much work, but large enough that each inactive page has a chance
@ -5415,14 +5483,16 @@ static int
__count_immobile_pages(struct zone *zone, struct page *page, int count)
{
unsigned long pfn, iter, found;
int mt;
/*
* For avoiding noise data, lru_add_drain_all() should be called
* If ZONE_MOVABLE, the zone never contains immobile pages
*/
if (zone_idx(zone) == ZONE_MOVABLE)
return true;
if (get_pageblock_migratetype(page) == MIGRATE_MOVABLE)
mt = get_pageblock_migratetype(page);
if (mt == MIGRATE_MOVABLE || is_migrate_cma(mt))
return true;
pfn = page_to_pfn(page);
@ -5539,7 +5609,7 @@ out:
return ret;
}
void unset_migratetype_isolate(struct page *page)
void unset_migratetype_isolate(struct page *page, unsigned migratetype)
{
struct zone *zone;
unsigned long flags;
@ -5547,12 +5617,259 @@ void unset_migratetype_isolate(struct page *page)
spin_lock_irqsave(&zone->lock, flags);
if (get_pageblock_migratetype(page) != MIGRATE_ISOLATE)
goto out;
set_pageblock_migratetype(page, MIGRATE_MOVABLE);
move_freepages_block(zone, page, MIGRATE_MOVABLE);
set_pageblock_migratetype(page, migratetype);
move_freepages_block(zone, page, migratetype);
out:
spin_unlock_irqrestore(&zone->lock, flags);
}
#ifdef CONFIG_CMA
static unsigned long pfn_max_align_down(unsigned long pfn)
{
return pfn & ~(max_t(unsigned long, MAX_ORDER_NR_PAGES,
pageblock_nr_pages) - 1);
}
static unsigned long pfn_max_align_up(unsigned long pfn)
{
return ALIGN(pfn, max_t(unsigned long, MAX_ORDER_NR_PAGES,
pageblock_nr_pages));
}
static struct page *
__alloc_contig_migrate_alloc(struct page *page, unsigned long private,
int **resultp)
{
return alloc_page(GFP_HIGHUSER_MOVABLE);
}
/* [start, end) must belong to a single zone. */
static int __alloc_contig_migrate_range(unsigned long start, unsigned long end)
{
/* This function is based on compact_zone() from compaction.c. */
unsigned long pfn = start;
unsigned int tries = 0;
int ret = 0;
struct compact_control cc = {
.nr_migratepages = 0,
.order = -1,
.zone = page_zone(pfn_to_page(start)),
.sync = true,
};
INIT_LIST_HEAD(&cc.migratepages);
migrate_prep_local();
while (pfn < end || !list_empty(&cc.migratepages)) {
if (fatal_signal_pending(current)) {
ret = -EINTR;
break;
}
if (list_empty(&cc.migratepages)) {
cc.nr_migratepages = 0;
pfn = isolate_migratepages_range(cc.zone, &cc,
pfn, end);
if (!pfn) {
ret = -EINTR;
break;
}
tries = 0;
} else if (++tries == 5) {
ret = ret < 0 ? ret : -EBUSY;
break;
}
ret = migrate_pages(&cc.migratepages,
__alloc_contig_migrate_alloc,
0, false, MIGRATE_SYNC);
}
putback_lru_pages(&cc.migratepages);
return ret > 0 ? 0 : ret;
}
/*
* Update zone's cma pages counter used for watermark level calculation.
*/
static inline void __update_cma_watermarks(struct zone *zone, int count)
{
unsigned long flags;
spin_lock_irqsave(&zone->lock, flags);
zone->min_cma_pages += count;
spin_unlock_irqrestore(&zone->lock, flags);
setup_per_zone_wmarks();
}
/*
* Trigger memory pressure bump to reclaim some pages in order to be able to
* allocate 'count' pages in single page units. Does similar work as
*__alloc_pages_slowpath() function.
*/
static int __reclaim_pages(struct zone *zone, gfp_t gfp_mask, int count)
{
enum zone_type high_zoneidx = gfp_zone(gfp_mask);
struct zonelist *zonelist = node_zonelist(0, gfp_mask);
int did_some_progress = 0;
int order = 1;
/*
* Increase level of watermarks to force kswapd do his job
* to stabilise at new watermark level.
*/
__update_cma_watermarks(zone, count);
/* Obey watermarks as if the page was being allocated */
while (!zone_watermark_ok(zone, 0, low_wmark_pages(zone), 0, 0)) {
wake_all_kswapd(order, zonelist, high_zoneidx, zone_idx(zone));
did_some_progress = __perform_reclaim(gfp_mask, order, zonelist,
NULL);
if (!did_some_progress) {
/* Exhausted what can be done so it's blamo time */
out_of_memory(zonelist, gfp_mask, order, NULL, false);
}
}
/* Restore original watermark levels. */
__update_cma_watermarks(zone, -count);
return count;
}
/**
* alloc_contig_range() -- tries to allocate given range of pages
* @start: start PFN to allocate
* @end: one-past-the-last PFN to allocate
* @migratetype: migratetype of the underlaying pageblocks (either
* #MIGRATE_MOVABLE or #MIGRATE_CMA). All pageblocks
* in range must have the same migratetype and it must
* be either of the two.
*
* The PFN range does not have to be pageblock or MAX_ORDER_NR_PAGES
* aligned, however it's the caller's responsibility to guarantee that
* we are the only thread that changes migrate type of pageblocks the
* pages fall in.
*
* The PFN range must belong to a single zone.
*
* Returns zero on success or negative error code. On success all
* pages which PFN is in [start, end) are allocated for the caller and
* need to be freed with free_contig_range().
*/
int alloc_contig_range(unsigned long start, unsigned long end,
unsigned migratetype)
{
struct zone *zone = page_zone(pfn_to_page(start));
unsigned long outer_start, outer_end;
int ret = 0, order;
/*
* What we do here is we mark all pageblocks in range as
* MIGRATE_ISOLATE. Because pageblock and max order pages may
* have different sizes, and due to the way page allocator
* work, we align the range to biggest of the two pages so
* that page allocator won't try to merge buddies from
* different pageblocks and change MIGRATE_ISOLATE to some
* other migration type.
*
* Once the pageblocks are marked as MIGRATE_ISOLATE, we
* migrate the pages from an unaligned range (ie. pages that
* we are interested in). This will put all the pages in
* range back to page allocator as MIGRATE_ISOLATE.
*
* When this is done, we take the pages in range from page
* allocator removing them from the buddy system. This way
* page allocator will never consider using them.
*
* This lets us mark the pageblocks back as
* MIGRATE_CMA/MIGRATE_MOVABLE so that free pages in the
* aligned range but not in the unaligned, original range are
* put back to page allocator so that buddy can use them.
*/
ret = start_isolate_page_range(pfn_max_align_down(start),
pfn_max_align_up(end), migratetype);
if (ret)
goto done;
ret = __alloc_contig_migrate_range(start, end);
if (ret)
goto done;
/*
* Pages from [start, end) are within a MAX_ORDER_NR_PAGES
* aligned blocks that are marked as MIGRATE_ISOLATE. What's
* more, all pages in [start, end) are free in page allocator.
* What we are going to do is to allocate all pages from
* [start, end) (that is remove them from page allocator).
*
* The only problem is that pages at the beginning and at the
* end of interesting range may be not aligned with pages that
* page allocator holds, ie. they can be part of higher order
* pages. Because of this, we reserve the bigger range and
* once this is done free the pages we are not interested in.
*
* We don't have to hold zone->lock here because the pages are
* isolated thus they won't get removed from buddy.
*/
lru_add_drain_all();
drain_all_pages();
order = 0;
outer_start = start;
while (!PageBuddy(pfn_to_page(outer_start))) {
if (++order >= MAX_ORDER) {
ret = -EBUSY;
goto done;
}
outer_start &= ~0UL << order;
}
/* Make sure the range is really isolated. */
if (test_pages_isolated(outer_start, end)) {
pr_warn("alloc_contig_range test_pages_isolated(%lx, %lx) failed\n",
outer_start, end);
ret = -EBUSY;
goto done;
}
/*
* Reclaim enough pages to make sure that contiguous allocation
* will not starve the system.
*/
__reclaim_pages(zone, GFP_HIGHUSER_MOVABLE, end-start);
/* Grab isolated pages from freelists. */
outer_end = isolate_freepages_range(outer_start, end);
if (!outer_end) {
ret = -EBUSY;
goto done;
}
/* Free head and tail (if any) */
if (start != outer_start)
free_contig_range(outer_start, start - outer_start);
if (end != outer_end)
free_contig_range(end, outer_end - end);
done:
undo_isolate_page_range(pfn_max_align_down(start),
pfn_max_align_up(end), migratetype);
return ret;
}
void free_contig_range(unsigned long pfn, unsigned nr_pages)
{
for (; nr_pages--; ++pfn)
__free_page(pfn_to_page(pfn));
}
#endif
#ifdef CONFIG_MEMORY_HOTREMOVE
/*
* All pages in the range must be isolated before calling this.

15
mm/page_isolation.c
View file

@ -24,6 +24,7 @@ __first_valid_page(unsigned long pfn, unsigned long nr_pages)
* to be MIGRATE_ISOLATE.
* @start_pfn: The lower PFN of the range to be isolated.
* @end_pfn: The upper PFN of the range to be isolated.
* @migratetype: migrate type to set in error recovery.
*
* Making page-allocation-type to be MIGRATE_ISOLATE means free pages in
* the range will never be allocated. Any free pages and pages freed in the
@ -32,8 +33,8 @@ __first_valid_page(unsigned long pfn, unsigned long nr_pages)
* start_pfn/end_pfn must be aligned to pageblock_order.
* Returns 0 on success and -EBUSY if any part of range cannot be isolated.
*/
int
start_isolate_page_range(unsigned long start_pfn, unsigned long end_pfn)
int start_isolate_page_range(unsigned long start_pfn, unsigned long end_pfn,
unsigned migratetype)
{
unsigned long pfn;
unsigned long undo_pfn;
@ -56,7 +57,7 @@ undo:
for (pfn = start_pfn;
pfn < undo_pfn;
pfn += pageblock_nr_pages)
unset_migratetype_isolate(pfn_to_page(pfn));
unset_migratetype_isolate(pfn_to_page(pfn), migratetype);
return -EBUSY;
}
@ -64,8 +65,8 @@ undo:
/*
* Make isolated pages available again.
*/
int
undo_isolate_page_range(unsigned long start_pfn, unsigned long end_pfn)
int undo_isolate_page_range(unsigned long start_pfn, unsigned long end_pfn,
unsigned migratetype)
{
unsigned long pfn;
struct page *page;
@ -77,7 +78,7 @@ undo_isolate_page_range(unsigned long start_pfn, unsigned long end_pfn)
page = __first_valid_page(pfn, pageblock_nr_pages);
if (!page || get_pageblock_migratetype(page) != MIGRATE_ISOLATE)
continue;
unset_migratetype_isolate(page);
unset_migratetype_isolate(page, migratetype);
}
return 0;
}
@ -86,7 +87,7 @@ undo_isolate_page_range(unsigned long start_pfn, unsigned long end_pfn)
* all pages in [start_pfn...end_pfn) must be in the same zone.
* zone->lock must be held before call this.
*
* Returns 1 if all pages in the range is isolated.
* Returns 1 if all pages in the range are isolated.
*/
static int
__test_page_isolated_in_pageblock(unsigned long pfn, unsigned long end_pfn)

3
mm/vmstat.c
View file

@ -613,6 +613,9 @@ static char * const migratetype_names[MIGRATE_TYPES] = {
"Reclaimable",
"Movable",
"Reserve",
#ifdef CONFIG_CMA
"CMA",
#endif
"Isolate",
};