Re: [PATCH v2 06/10] CMA: generalize CMA reserved area management functionality
On Sat, Jun 14, 2014 at 03:46:44PM +0530, Aneesh Kumar K.V wrote:
Joonsoo Kim iamjoonsoo@lge.com writes:
Currently, there are two users on CMA functionality, one is the DMA
subsystem and the other is the kvm on powerpc. They have their own code
to manage CMA reserved area even if they looks really similar.
From my guess, it is caused by some needs on bitmap management. Kvm side
wants to maintain bitmap not for 1 page, but for more size. Eventually it
use bitmap where one bit represents 64 pages.
When I implement CMA related patches, I should change those two places
to apply my change and it seem to be painful to me. I want to change
this situation and reduce future code management overhead through
this patch.
This change could also help developer who want to use CMA in their
new feature development, since they can use CMA easily without
copying pasting this reserved area management code.
In previous patches, we have prepared some features to generalize
CMA reserved area management and now it's time to do it. This patch
moves core functions to mm/cma.c and change DMA APIs to use
these functions.
There is no functional change in DMA APIs.
v2: There is no big change from v1 in mm/cma.c. Mostly renaming.
Acked-by: Michal Nazarewicz min...@mina86.com
Signed-off-by: Joonsoo Kim iamjoonsoo@lge.com
.
+
+ mask = cma_bitmap_aligned_mask(cma, align);
+ bitmap_maxno = cma_bitmap_maxno(cma);
+ nr_bits = cma_bitmap_pages_to_bits(cma, count);
+
+ for (;;) {
+ mutex_lock(cma-lock);
+ bitmapno = bitmap_find_next_zero_area(cma-bitmap,
+ bitmap_maxno, start, nr_bits, mask);
+ if (bitmapno = bitmap_maxno) {
+ mutex_unlock(cma-lock);
+ break;
+ }
+ bitmap_set(cma-bitmap, bitmapno, nr_bits);
+ /*
+* It's safe to drop the lock here. We've marked this region for
+* our exclusive use. If the migration fails we will take the
+* lock again and unmark it.
+*/
+ mutex_unlock(cma-lock);
+
+ pfn = cma-base_pfn + (bitmapno cma-order_per_bit);
+ mutex_lock(cma_mutex);
+ ret = alloc_contig_range(pfn, pfn + count, MIGRATE_CMA);
+ mutex_unlock(cma_mutex);
+ if (ret == 0) {
+ page = pfn_to_page(pfn);
+ break;
+ } else if (ret != -EBUSY) {
+ clear_cma_bitmap(cma, pfn, count);
+ break;
+ }
+
For setting bit map we do
bitmap_set(cma-bitmap, bitmapno, nr_bits);
alloc_contig()..
if (error)
clear_cma_bitmap(cma, pfn, count);
Why ?
why not bitmap_clear() ?
Unlike your psuedo code, for setting bitmap, we do
- grab the mutex
- bitmap_set
- release the mutex
clear_cma_bitmap() handles these things.
Thanks.
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Re: [PATCH v2 06/10] CMA: generalize CMA reserved area management functionality
Joonsoo Kim iamjoonsoo@lge.com writes:
Currently, there are two users on CMA functionality, one is the DMA
subsystem and the other is the kvm on powerpc. They have their own code
to manage CMA reserved area even if they looks really similar.
From my guess, it is caused by some needs on bitmap management. Kvm side
wants to maintain bitmap not for 1 page, but for more size. Eventually it
use bitmap where one bit represents 64 pages.
When I implement CMA related patches, I should change those two places
to apply my change and it seem to be painful to me. I want to change
this situation and reduce future code management overhead through
this patch.
This change could also help developer who want to use CMA in their
new feature development, since they can use CMA easily without
copying pasting this reserved area management code.
In previous patches, we have prepared some features to generalize
CMA reserved area management and now it's time to do it. This patch
moves core functions to mm/cma.c and change DMA APIs to use
these functions.
There is no functional change in DMA APIs.
v2: There is no big change from v1 in mm/cma.c. Mostly renaming.
Acked-by: Michal Nazarewicz min...@mina86.com
Signed-off-by: Joonsoo Kim iamjoonsoo@lge.com
Reviewed-by: Aneesh Kumar K.V aneesh.ku...@linux.vnet.ibm.com
diff --git a/drivers/base/Kconfig b/drivers/base/Kconfig
index 00e13ce..4eac559 100644
--- a/drivers/base/Kconfig
+++ b/drivers/base/Kconfig
@@ -283,16 +283,6 @@ config CMA_ALIGNMENT
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
diff --git a/drivers/base/dma-contiguous.c b/drivers/base/dma-contiguous.c
index 9bc9340..f177f73 100644
--- a/drivers/base/dma-contiguous.c
+++ b/drivers/base/dma-contiguous.c
@@ -24,25 +24,10 @@
#include linux/memblock.h
#include linux/err.h
-#include linux/mm.h
-#include linux/mutex.h
-#include linux/page-isolation.h
#include linux/sizes.h
-#include linux/slab.h
-#include linux/swap.h
-#include linux/mm_types.h
#include linux/dma-contiguous.h
#include linux/log2.h
-
-struct cma {
- unsigned long base_pfn;
- unsigned long count;
- unsigned long *bitmap;
- int order_per_bit; /* Order of pages represented by one bit */
- struct mutexlock;
-};
-
-struct cma *dma_contiguous_default_area;
+#include linux/cma.h
#ifdef CONFIG_CMA_SIZE_MBYTES
#define CMA_SIZE_MBYTES CONFIG_CMA_SIZE_MBYTES
@@ -50,6 +35,8 @@ struct cma *dma_contiguous_default_area;
#define CMA_SIZE_MBYTES 0
#endif
+struct cma *dma_contiguous_default_area;
+
/*
* Default global CMA area size can be defined in kernel's .config.
* This is useful mainly for distro maintainers to create a kernel
@@ -156,199 +143,13 @@ void __init dma_contiguous_reserve(phys_addr_t limit)
}
}
-static DEFINE_MUTEX(cma_mutex);
-
-static unsigned long cma_bitmap_aligned_mask(struct cma *cma, int
align_order)
-{
- return (1 (align_order cma-order_per_bit)) - 1;
-}
-
-static unsigned long cma_bitmap_maxno(struct cma *cma)
-{
- return cma-count cma-order_per_bit;
-}
-
-static unsigned long cma_bitmap_pages_to_bits(struct cma *cma,
- unsigned long pages)
-{
- return ALIGN(pages, 1 cma-order_per_bit) cma-order_per_bit;
-}
-
-static void clear_cma_bitmap(struct cma *cma, unsigned long pfn, int count)
-{
- unsigned long bitmapno, nr_bits;
-
- bitmapno = (pfn - cma-base_pfn) cma-order_per_bit;
- nr_bits = cma_bitmap_pages_to_bits(cma, count);
-
- mutex_lock(cma-lock);
- bitmap_clear(cma-bitmap, bitmapno, nr_bits);
- mutex_unlock(cma-lock);
-}
-
-static int __init cma_activate_area(struct cma *cma)
-{
- int bitmap_maxno = cma_bitmap_maxno(cma);
- int bitmap_size = BITS_TO_LONGS(bitmap_maxno) * sizeof(long);
- unsigned long base_pfn = cma-base_pfn, pfn = base_pfn;
- unsigned i = cma-count pageblock_order;
- struct zone *zone;
-
- pr_debug(%s()\n, __func__);
-
- cma-bitmap = kzalloc(bitmap_size, GFP_KERNEL);
- if (!cma-bitmap)
- return -ENOMEM;
-
- 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));
- /*
- * alloc_contig_range requires the pfn range
- * specified to be in the same zone. Make this
- * simple by forcing the
Re: [PATCH v2 06/10] CMA: generalize CMA reserved area management functionality
Joonsoo Kim iamjoonsoo@lge.com writes:
Currently, there are two users on CMA functionality, one is the DMA
subsystem and the other is the kvm on powerpc. They have their own code
to manage CMA reserved area even if they looks really similar.
From my guess, it is caused by some needs on bitmap management. Kvm side
wants to maintain bitmap not for 1 page, but for more size. Eventually it
use bitmap where one bit represents 64 pages.
When I implement CMA related patches, I should change those two places
to apply my change and it seem to be painful to me. I want to change
this situation and reduce future code management overhead through
this patch.
This change could also help developer who want to use CMA in their
new feature development, since they can use CMA easily without
copying pasting this reserved area management code.
In previous patches, we have prepared some features to generalize
CMA reserved area management and now it's time to do it. This patch
moves core functions to mm/cma.c and change DMA APIs to use
these functions.
There is no functional change in DMA APIs.
v2: There is no big change from v1 in mm/cma.c. Mostly renaming.
Acked-by: Michal Nazarewicz min...@mina86.com
Signed-off-by: Joonsoo Kim iamjoonsoo@lge.com
Reviewed-by: Aneesh Kumar K.V aneesh.ku...@linux.vnet.ibm.com
diff --git a/drivers/base/Kconfig b/drivers/base/Kconfig
index 00e13ce..4eac559 100644
--- a/drivers/base/Kconfig
+++ b/drivers/base/Kconfig
@@ -283,16 +283,6 @@ config CMA_ALIGNMENT
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
diff --git a/drivers/base/dma-contiguous.c b/drivers/base/dma-contiguous.c
index 9bc9340..f177f73 100644
--- a/drivers/base/dma-contiguous.c
+++ b/drivers/base/dma-contiguous.c
@@ -24,25 +24,10 @@
#include linux/memblock.h
#include linux/err.h
-#include linux/mm.h
-#include linux/mutex.h
-#include linux/page-isolation.h
#include linux/sizes.h
-#include linux/slab.h
-#include linux/swap.h
-#include linux/mm_types.h
#include linux/dma-contiguous.h
#include linux/log2.h
-
-struct cma {
- unsigned long base_pfn;
- unsigned long count;
- unsigned long *bitmap;
- int order_per_bit; /* Order of pages represented by one bit */
- struct mutexlock;
-};
-
-struct cma *dma_contiguous_default_area;
+#include linux/cma.h
#ifdef CONFIG_CMA_SIZE_MBYTES
#define CMA_SIZE_MBYTES CONFIG_CMA_SIZE_MBYTES
@@ -50,6 +35,8 @@ struct cma *dma_contiguous_default_area;
#define CMA_SIZE_MBYTES 0
#endif
+struct cma *dma_contiguous_default_area;
+
/*
* Default global CMA area size can be defined in kernel's .config.
* This is useful mainly for distro maintainers to create a kernel
@@ -156,199 +143,13 @@ void __init dma_contiguous_reserve(phys_addr_t limit)
}
}
-static DEFINE_MUTEX(cma_mutex);
-
-static unsigned long cma_bitmap_aligned_mask(struct cma *cma, int
align_order)
-{
- return (1 (align_order cma-order_per_bit)) - 1;
-}
-
-static unsigned long cma_bitmap_maxno(struct cma *cma)
-{
- return cma-count cma-order_per_bit;
-}
-
-static unsigned long cma_bitmap_pages_to_bits(struct cma *cma,
- unsigned long pages)
-{
- return ALIGN(pages, 1 cma-order_per_bit) cma-order_per_bit;
-}
-
-static void clear_cma_bitmap(struct cma *cma, unsigned long pfn, int count)
-{
- unsigned long bitmapno, nr_bits;
-
- bitmapno = (pfn - cma-base_pfn) cma-order_per_bit;
- nr_bits = cma_bitmap_pages_to_bits(cma, count);
-
- mutex_lock(cma-lock);
- bitmap_clear(cma-bitmap, bitmapno, nr_bits);
- mutex_unlock(cma-lock);
-}
-
-static int __init cma_activate_area(struct cma *cma)
-{
- int bitmap_maxno = cma_bitmap_maxno(cma);
- int bitmap_size = BITS_TO_LONGS(bitmap_maxno) * sizeof(long);
- unsigned long base_pfn = cma-base_pfn, pfn = base_pfn;
- unsigned i = cma-count pageblock_order;
- struct zone *zone;
-
- pr_debug(%s()\n, __func__);
-
- cma-bitmap = kzalloc(bitmap_size, GFP_KERNEL);
- if (!cma-bitmap)
- return -ENOMEM;
-
- 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));
- /*
- * alloc_contig_range requires the pfn range
- * specified to be in the same zone. Make this
- * simple by forcing the
Re: [PATCH v2 06/10] CMA: generalize CMA reserved area management functionality
Joonsoo Kim iamjoonsoo@lge.com writes:
Currently, there are two users on CMA functionality, one is the DMA
subsystem and the other is the kvm on powerpc. They have their own code
to manage CMA reserved area even if they looks really similar.
From my guess, it is caused by some needs on bitmap management. Kvm side
wants to maintain bitmap not for 1 page, but for more size. Eventually it
use bitmap where one bit represents 64 pages.
When I implement CMA related patches, I should change those two places
to apply my change and it seem to be painful to me. I want to change
this situation and reduce future code management overhead through
this patch.
This change could also help developer who want to use CMA in their
new feature development, since they can use CMA easily without
copying pasting this reserved area management code.
In previous patches, we have prepared some features to generalize
CMA reserved area management and now it's time to do it. This patch
moves core functions to mm/cma.c and change DMA APIs to use
these functions.
There is no functional change in DMA APIs.
v2: There is no big change from v1 in mm/cma.c. Mostly renaming.
Acked-by: Michal Nazarewicz min...@mina86.com
Signed-off-by: Joonsoo Kim iamjoonsoo@lge.com
.
+
+ mask = cma_bitmap_aligned_mask(cma, align);
+ bitmap_maxno = cma_bitmap_maxno(cma);
+ nr_bits = cma_bitmap_pages_to_bits(cma, count);
+
+ for (;;) {
+ mutex_lock(cma-lock);
+ bitmapno = bitmap_find_next_zero_area(cma-bitmap,
+ bitmap_maxno, start, nr_bits, mask);
+ if (bitmapno = bitmap_maxno) {
+ mutex_unlock(cma-lock);
+ break;
+ }
+ bitmap_set(cma-bitmap, bitmapno, nr_bits);
+ /*
+ * It's safe to drop the lock here. We've marked this region for
+ * our exclusive use. If the migration fails we will take the
+ * lock again and unmark it.
+ */
+ mutex_unlock(cma-lock);
+
+ pfn = cma-base_pfn + (bitmapno cma-order_per_bit);
+ mutex_lock(cma_mutex);
+ ret = alloc_contig_range(pfn, pfn + count, MIGRATE_CMA);
+ mutex_unlock(cma_mutex);
+ if (ret == 0) {
+ page = pfn_to_page(pfn);
+ break;
+ } else if (ret != -EBUSY) {
+ clear_cma_bitmap(cma, pfn, count);
+ break;
+ }
+
For setting bit map we do
bitmap_set(cma-bitmap, bitmapno, nr_bits);
alloc_contig()..
if (error)
clear_cma_bitmap(cma, pfn, count);
Why ?
why not bitmap_clear() ?
-aneesh
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Re: [PATCH v2 06/10] CMA: generalize CMA reserved area management functionality
On Thu, Jun 12, 2014 at 12:21:43PM +0900, Joonsoo Kim wrote:
Currently, there are two users on CMA functionality, one is the DMA
subsystem and the other is the kvm on powerpc. They have their own code
to manage CMA reserved area even if they looks really similar.
From my guess, it is caused by some needs on bitmap management. Kvm side
wants to maintain bitmap not for 1 page, but for more size. Eventually it
use bitmap where one bit represents 64 pages.
When I implement CMA related patches, I should change those two places
to apply my change and it seem to be painful to me. I want to change
this situation and reduce future code management overhead through
this patch.
This change could also help developer who want to use CMA in their
new feature development, since they can use CMA easily without
copying pasting this reserved area management code.
In previous patches, we have prepared some features to generalize
CMA reserved area management and now it's time to do it. This patch
moves core functions to mm/cma.c and change DMA APIs to use
these functions.
There is no functional change in DMA APIs.
v2: There is no big change from v1 in mm/cma.c. Mostly renaming.
Acked-by: Michal Nazarewicz min...@mina86.com
Signed-off-by: Joonsoo Kim iamjoonsoo@lge.com
Acutally, I want to remove bool return of cma_release but it's not
a out of scope in this patchset.
Acked-by: Minchan Kim minc...@kernel.org
diff --git a/drivers/base/Kconfig b/drivers/base/Kconfig
index 00e13ce..4eac559 100644
--- a/drivers/base/Kconfig
+++ b/drivers/base/Kconfig
@@ -283,16 +283,6 @@ config CMA_ALIGNMENT
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
diff --git a/drivers/base/dma-contiguous.c b/drivers/base/dma-contiguous.c
index 9bc9340..f177f73 100644
--- a/drivers/base/dma-contiguous.c
+++ b/drivers/base/dma-contiguous.c
@@ -24,25 +24,10 @@
#include linux/memblock.h
#include linux/err.h
-#include linux/mm.h
-#include linux/mutex.h
-#include linux/page-isolation.h
#include linux/sizes.h
-#include linux/slab.h
-#include linux/swap.h
-#include linux/mm_types.h
#include linux/dma-contiguous.h
#include linux/log2.h
Should we remain log2.h in here?
-
-struct cma {
- unsigned long base_pfn;
- unsigned long count;
- unsigned long *bitmap;
- int order_per_bit; /* Order of pages represented by one bit */
- struct mutexlock;
-};
-
-struct cma *dma_contiguous_default_area;
+#include linux/cma.h
#ifdef CONFIG_CMA_SIZE_MBYTES
#define CMA_SIZE_MBYTES CONFIG_CMA_SIZE_MBYTES
@@ -50,6 +35,8 @@ struct cma *dma_contiguous_default_area;
#define CMA_SIZE_MBYTES 0
#endif
+struct cma *dma_contiguous_default_area;
+
/*
* Default global CMA area size can be defined in kernel's .config.
* This is useful mainly for distro maintainers to create a kernel
@@ -156,199 +143,13 @@ void __init dma_contiguous_reserve(phys_addr_t limit)
}
}
-static DEFINE_MUTEX(cma_mutex);
-
-static unsigned long cma_bitmap_aligned_mask(struct cma *cma, int
align_order)
-{
- return (1 (align_order cma-order_per_bit)) - 1;
-}
-
-static unsigned long cma_bitmap_maxno(struct cma *cma)
-{
- return cma-count cma-order_per_bit;
-}
-
-static unsigned long cma_bitmap_pages_to_bits(struct cma *cma,
- unsigned long pages)
-{
- return ALIGN(pages, 1 cma-order_per_bit) cma-order_per_bit;
-}
-
-static void clear_cma_bitmap(struct cma *cma, unsigned long pfn, int count)
-{
- unsigned long bitmapno, nr_bits;
-
- bitmapno = (pfn - cma-base_pfn) cma-order_per_bit;
- nr_bits = cma_bitmap_pages_to_bits(cma, count);
-
- mutex_lock(cma-lock);
- bitmap_clear(cma-bitmap, bitmapno, nr_bits);
- mutex_unlock(cma-lock);
-}
-
-static int __init cma_activate_area(struct cma *cma)
-{
- int bitmap_maxno = cma_bitmap_maxno(cma);
- int bitmap_size = BITS_TO_LONGS(bitmap_maxno) * sizeof(long);
- unsigned long base_pfn = cma-base_pfn, pfn = base_pfn;
- unsigned i = cma-count pageblock_order;
- struct zone *zone;
-
- pr_debug(%s()\n, __func__);
-
- cma-bitmap = kzalloc(bitmap_size, GFP_KERNEL);
- if (!cma-bitmap)
- return -ENOMEM;
-
- 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));
- /*
- *
Re: [PATCH v2 06/10] CMA: generalize CMA reserved area management functionality
On Thu, Jun 12, 2014 at 04:13:11PM +0900, Minchan Kim wrote: On Thu, Jun 12, 2014 at 12:21:43PM +0900, Joonsoo Kim wrote: Currently, there are two users on CMA functionality, one is the DMA subsystem and the other is the kvm on powerpc. They have their own code to manage CMA reserved area even if they looks really similar. From my guess, it is caused by some needs on bitmap management. Kvm side wants to maintain bitmap not for 1 page, but for more size. Eventually it use bitmap where one bit represents 64 pages. When I implement CMA related patches, I should change those two places to apply my change and it seem to be painful to me. I want to change this situation and reduce future code management overhead through this patch. This change could also help developer who want to use CMA in their new feature development, since they can use CMA easily without copying pasting this reserved area management code. In previous patches, we have prepared some features to generalize CMA reserved area management and now it's time to do it. This patch moves core functions to mm/cma.c and change DMA APIs to use these functions. There is no functional change in DMA APIs. v2: There is no big change from v1 in mm/cma.c. Mostly renaming. Acked-by: Michal Nazarewicz min...@mina86.com Signed-off-by: Joonsoo Kim iamjoonsoo@lge.com Acutally, I want to remove bool return of cma_release but it's not a out of scope in this patchset. Acked-by: Minchan Kim minc...@kernel.org diff --git a/drivers/base/Kconfig b/drivers/base/Kconfig index 00e13ce..4eac559 100644 --- a/drivers/base/Kconfig +++ b/drivers/base/Kconfig @@ -283,16 +283,6 @@ config CMA_ALIGNMENT 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 diff --git a/drivers/base/dma-contiguous.c b/drivers/base/dma-contiguous.c index 9bc9340..f177f73 100644 --- a/drivers/base/dma-contiguous.c +++ b/drivers/base/dma-contiguous.c @@ -24,25 +24,10 @@ #include linux/memblock.h #include linux/err.h -#include linux/mm.h -#include linux/mutex.h -#include linux/page-isolation.h #include linux/sizes.h -#include linux/slab.h -#include linux/swap.h -#include linux/mm_types.h #include linux/dma-contiguous.h #include linux/log2.h Should we remain log2.h in here? We should remove it. I will fix it. Thanks. -- To unsubscribe from this list: send the line unsubscribe kvm-ppc in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: [PATCH v2 06/10] CMA: generalize CMA reserved area management functionality
On 06/12/2014 11:21 AM, Joonsoo Kim wrote:
Currently, there are two users on CMA functionality, one is the DMA
subsystem and the other is the kvm on powerpc. They have their own code
to manage CMA reserved area even if they looks really similar.
From my guess, it is caused by some needs on bitmap management. Kvm side
wants to maintain bitmap not for 1 page, but for more size. Eventually it
use bitmap where one bit represents 64 pages.
When I implement CMA related patches, I should change those two places
to apply my change and it seem to be painful to me. I want to change
this situation and reduce future code management overhead through
this patch.
This change could also help developer who want to use CMA in their
new feature development, since they can use CMA easily without
copying pasting this reserved area management code.
In previous patches, we have prepared some features to generalize
CMA reserved area management and now it's time to do it. This patch
moves core functions to mm/cma.c and change DMA APIs to use
these functions.
There is no functional change in DMA APIs.
v2: There is no big change from v1 in mm/cma.c. Mostly renaming.
Acked-by: Michal Nazarewicz min...@mina86.com
Signed-off-by: Joonsoo Kim iamjoonsoo@lge.com
Acked-by: Zhang Yanfei zhangyan...@cn.fujitsu.com
diff --git a/drivers/base/Kconfig b/drivers/base/Kconfig
index 00e13ce..4eac559 100644
--- a/drivers/base/Kconfig
+++ b/drivers/base/Kconfig
@@ -283,16 +283,6 @@ config CMA_ALIGNMENT
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
diff --git a/drivers/base/dma-contiguous.c b/drivers/base/dma-contiguous.c
index 9bc9340..f177f73 100644
--- a/drivers/base/dma-contiguous.c
+++ b/drivers/base/dma-contiguous.c
@@ -24,25 +24,10 @@
#include linux/memblock.h
#include linux/err.h
-#include linux/mm.h
-#include linux/mutex.h
-#include linux/page-isolation.h
#include linux/sizes.h
-#include linux/slab.h
-#include linux/swap.h
-#include linux/mm_types.h
#include linux/dma-contiguous.h
#include linux/log2.h
-
-struct cma {
- unsigned long base_pfn;
- unsigned long count;
- unsigned long *bitmap;
- int order_per_bit; /* Order of pages represented by one bit */
- struct mutexlock;
-};
-
-struct cma *dma_contiguous_default_area;
+#include linux/cma.h
#ifdef CONFIG_CMA_SIZE_MBYTES
#define CMA_SIZE_MBYTES CONFIG_CMA_SIZE_MBYTES
@@ -50,6 +35,8 @@ struct cma *dma_contiguous_default_area;
#define CMA_SIZE_MBYTES 0
#endif
+struct cma *dma_contiguous_default_area;
+
/*
* Default global CMA area size can be defined in kernel's .config.
* This is useful mainly for distro maintainers to create a kernel
@@ -156,199 +143,13 @@ void __init dma_contiguous_reserve(phys_addr_t limit)
}
}
-static DEFINE_MUTEX(cma_mutex);
-
-static unsigned long cma_bitmap_aligned_mask(struct cma *cma, int
align_order)
-{
- return (1 (align_order cma-order_per_bit)) - 1;
-}
-
-static unsigned long cma_bitmap_maxno(struct cma *cma)
-{
- return cma-count cma-order_per_bit;
-}
-
-static unsigned long cma_bitmap_pages_to_bits(struct cma *cma,
- unsigned long pages)
-{
- return ALIGN(pages, 1 cma-order_per_bit) cma-order_per_bit;
-}
-
-static void clear_cma_bitmap(struct cma *cma, unsigned long pfn, int count)
-{
- unsigned long bitmapno, nr_bits;
-
- bitmapno = (pfn - cma-base_pfn) cma-order_per_bit;
- nr_bits = cma_bitmap_pages_to_bits(cma, count);
-
- mutex_lock(cma-lock);
- bitmap_clear(cma-bitmap, bitmapno, nr_bits);
- mutex_unlock(cma-lock);
-}
-
-static int __init cma_activate_area(struct cma *cma)
-{
- int bitmap_maxno = cma_bitmap_maxno(cma);
- int bitmap_size = BITS_TO_LONGS(bitmap_maxno) * sizeof(long);
- unsigned long base_pfn = cma-base_pfn, pfn = base_pfn;
- unsigned i = cma-count pageblock_order;
- struct zone *zone;
-
- pr_debug(%s()\n, __func__);
-
- cma-bitmap = kzalloc(bitmap_size, GFP_KERNEL);
- if (!cma-bitmap)
- return -ENOMEM;
-
- 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));
- /*
- * alloc_contig_range requires the pfn range
- * specified to be in the same zone. Make this
- * simple by forcing
