Hello,

On 6/24/2013 10:25 AM, Aneesh Kumar K.V wrote:
From: "Aneesh Kumar K.V" <aneesh.ku...@linux.vnet.ibm.com>

We want to use CMA for allocating hash page table and real mode area for
PPC64. Hence move DMA contiguous related changes into a seperate config
so that ppc64 can enable CMA without requiring DMA contiguous.

Signed-off-by: Aneesh Kumar K.V <aneesh.ku...@linux.vnet.ibm.com>

It's nice to see that CMA is gaining another client in mainline Linux kernel.
I also like the idea of adding CONFIG_DMA_CMA for DMA-mapping related CMA
use to let others to use alloc_contig_range() interface.

However I noticed that You have almost copied the whole drivers/base.c for
separate use with PPC64 KVM. Is this really necessary? I think it should be
possible to isolate some common code, which plays with contiguous region
management and use it for both alloc_contig_range() clients (dma-mapping and
ppc64 kvm).

---
  arch/arm/configs/omap2plus_defconfig  |  2 +-
  arch/arm/configs/tegra_defconfig      |  2 +-
  arch/arm/include/asm/dma-contiguous.h |  2 +-
  arch/arm/mm/dma-mapping.c             |  6 +++---
  drivers/base/Kconfig                  | 21 +++++----------------
  drivers/base/Makefile                 |  2 +-
  include/linux/dma-contiguous.h        |  2 +-
  mm/Kconfig                            | 20 ++++++++++++++++++++
  8 files changed, 33 insertions(+), 24 deletions(-)

diff --git a/arch/arm/configs/omap2plus_defconfig 
b/arch/arm/configs/omap2plus_defconfig
index abbe319..098268f 100644
--- a/arch/arm/configs/omap2plus_defconfig
+++ b/arch/arm/configs/omap2plus_defconfig
@@ -71,7 +71,7 @@ CONFIG_MAC80211=m
  CONFIG_MAC80211_RC_PID=y
  CONFIG_MAC80211_RC_DEFAULT_PID=y
  CONFIG_UEVENT_HELPER_PATH="/sbin/hotplug"
-CONFIG_CMA=y
+CONFIG_DMA_CMA=y
  CONFIG_CONNECTOR=y
  CONFIG_DEVTMPFS=y
  CONFIG_DEVTMPFS_MOUNT=y
diff --git a/arch/arm/configs/tegra_defconfig b/arch/arm/configs/tegra_defconfig
index f7ba3161..34ae8f2 100644
--- a/arch/arm/configs/tegra_defconfig
+++ b/arch/arm/configs/tegra_defconfig
@@ -79,7 +79,7 @@ CONFIG_RFKILL_GPIO=y
  CONFIG_DEVTMPFS=y
  CONFIG_DEVTMPFS_MOUNT=y
  # CONFIG_FIRMWARE_IN_KERNEL is not set
-CONFIG_CMA=y
+CONFIG_DMA_CMA=y
  CONFIG_MTD=y
  CONFIG_MTD_CHAR=y
  CONFIG_MTD_M25P80=y
diff --git a/arch/arm/include/asm/dma-contiguous.h 
b/arch/arm/include/asm/dma-contiguous.h
index 3ed37b4..e072bb2 100644
--- a/arch/arm/include/asm/dma-contiguous.h
+++ b/arch/arm/include/asm/dma-contiguous.h
@@ -2,7 +2,7 @@
  #define ASMARM_DMA_CONTIGUOUS_H
#ifdef __KERNEL__
-#ifdef CONFIG_CMA
+#ifdef CONFIG_DMA_CMA
#include <linux/types.h>
  #include <asm-generic/dma-contiguous.h>
diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c
index ef3e0f3..1fb40dc 100644
--- a/arch/arm/mm/dma-mapping.c
+++ b/arch/arm/mm/dma-mapping.c
@@ -358,7 +358,7 @@ static int __init atomic_pool_init(void)
        if (!pages)
                goto no_pages;
- if (IS_ENABLED(CONFIG_CMA))
+       if (IS_ENABLED(CONFIG_DMA_CMA))
                ptr = __alloc_from_contiguous(NULL, pool->size, prot, &page,
                                              atomic_pool_init);
        else
@@ -670,7 +670,7 @@ static void *__dma_alloc(struct device *dev, size_t size, 
dma_addr_t *handle,
                addr = __alloc_simple_buffer(dev, size, gfp, &page);
        else if (!(gfp & __GFP_WAIT))
                addr = __alloc_from_pool(size, &page);
-       else if (!IS_ENABLED(CONFIG_CMA))
+       else if (!IS_ENABLED(CONFIG_DMA_CMA))
                addr = __alloc_remap_buffer(dev, size, gfp, prot, &page, 
caller);
        else
                addr = __alloc_from_contiguous(dev, size, prot, &page, caller);
@@ -759,7 +759,7 @@ static void __arm_dma_free(struct device *dev, size_t size, 
void *cpu_addr,
                __dma_free_buffer(page, size);
        } else if (__free_from_pool(cpu_addr, size)) {
                return;
-       } else if (!IS_ENABLED(CONFIG_CMA)) {
+       } else if (!IS_ENABLED(CONFIG_DMA_CMA)) {
                __dma_free_remap(cpu_addr, size);
                __dma_free_buffer(page, size);
        } else {
diff --git a/drivers/base/Kconfig b/drivers/base/Kconfig
index 07abd9d..74b7c98 100644
--- a/drivers/base/Kconfig
+++ b/drivers/base/Kconfig
@@ -202,11 +202,10 @@ config DMA_SHARED_BUFFER
          APIs extension; the file's descriptor can then be passed on to other
          driver.
-config CMA
-       bool "Contiguous Memory Allocator"
-       depends on HAVE_DMA_CONTIGUOUS && HAVE_MEMBLOCK
-       select MIGRATION
-       select MEMORY_ISOLATION
+config DMA_CMA
+       bool "DMA Contiguous Memory Allocator"
+       depends on HAVE_DMA_CONTIGUOUS
+       select CMA
        help
          This enables the Contiguous Memory Allocator which allows drivers
          to allocate big physically-contiguous blocks of memory for use with
@@ -215,17 +214,7 @@ config CMA
          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.
-
+if  DMA_CMA
  comment "Default contiguous memory area size:"
config CMA_SIZE_MBYTES
diff --git a/drivers/base/Makefile b/drivers/base/Makefile
index 4e22ce3..5d93bb5 100644
--- a/drivers/base/Makefile
+++ b/drivers/base/Makefile
@@ -6,7 +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-$(CONFIG_DMA_CMA) += dma-contiguous.o
  obj-y                 += power/
  obj-$(CONFIG_HAS_DMA) += dma-mapping.o
  obj-$(CONFIG_HAVE_GENERIC_DMA_COHERENT) += dma-coherent.o
diff --git a/include/linux/dma-contiguous.h b/include/linux/dma-contiguous.h
index 01b5c84..00141d3 100644
--- a/include/linux/dma-contiguous.h
+++ b/include/linux/dma-contiguous.h
@@ -57,7 +57,7 @@ struct cma;
  struct page;
  struct device;
-#ifdef CONFIG_CMA
+#ifdef CONFIG_DMA_CMA
/*
   * There is always at least global CMA area and a few optional device
diff --git a/mm/Kconfig b/mm/Kconfig
index e742d06..b362369 100644
--- a/mm/Kconfig
+++ b/mm/Kconfig
@@ -477,3 +477,23 @@ config FRONTSWAP
          and swap data is stored as normal on the matching swap device.
If unsure, say Y to enable frontswap.
+
+config CMA
+       bool "Contiguous Memory Allocator"
+       depends on HAVE_MEMBLOCK
+       select MIGRATION
+       select MEMORY_ISOLATION
+       help
+         This enables the Contiguous Memory Allocator which allows other
+         subsystem to allocate big physically-contiguous blocks of memory
+
+         If unsure, say "n".
+
+config CMA_DEBUG
+       bool "CMA debug messages (DEVELOPMENT)"
+       depends on DEBUG_KERNEL && CMA
+       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.

Best regards
--
Marek Szyprowski
Samsung R&D Institute Poland


_______________________________________________
Linuxppc-dev mailing list
Linuxppc-dev@lists.ozlabs.org
https://lists.ozlabs.org/listinfo/linuxppc-dev

Reply via email to