Re: [Xenomai-core] [Patch 1/7] Support for non cached memory mappings
Gilles Chanteperdrix wrote:
In addition to support for non cached memory mappings, this patch implements
xnheap_init_mapped and xnheap_destroy_mapped in the !CONFIG_XENO_OPT_PERVASIVE
case. This avoids a lot of #ifdefs for users of these functions without
user-space support (posix skin shared memories, and the new semaphore heaps,
heaps where is allocated the memory used for storing semaphores counters and
mutexes owner fields).
Looks good. I would suggest to make xnheap_init_mapped() whine and bail out when
non-cached DMA memory is requested though.
---
include/asm-generic/wrappers.h | 12 +---
include/native/heap.h |1
include/nucleus/heap.h |2 +
ksrc/nucleus/heap.c| 55
+++--
ksrc/skins/native/heap.c |8 +
5 files changed, 66 insertions(+), 12 deletions(-)
Index: include/native/heap.h
===
--- include/native/heap.h (revision 3738)
+++ include/native/heap.h (working copy)
@@ -33,6 +33,7 @@
#define H_MAPPABLE 0x200 /* Memory is mappable to user-space. */
#define H_SINGLE 0x400 /* Manage as single-block area. */
#define H_SHARED (H_MAPPABLE|H_SINGLE) /* I.e. shared memory segment. */
+#define H_NONCACHED 0x800
/** Structure containing heap-information useful to users.
*
Index: include/asm-generic/wrappers.h
===
--- include/asm-generic/wrappers.h(revision 3738)
+++ include/asm-generic/wrappers.h(working copy)
@@ -62,7 +62,7 @@ unsigned long __va_to_kva(unsigned long
#define wrap_remap_vm_page(vma,from,to) ({ \
vma-vm_flags |= VM_RESERVED; \
-remap_page_range(from,virt_to_phys((void
*)__va_to_kva(to)),PAGE_SIZE,PAGE_SHARED); \
+remap_page_range(from,virt_to_phys((void
*)__va_to_kva(to)),PAGE_SIZE,vma-vm_page_prot); \
})
#define wrap_remap_io_page_range(vma,from,to,size,prot) ({ \
vma-vm_flags |= VM_RESERVED; \
@@ -223,7 +223,7 @@ unsigned long __va_to_kva(unsigned long
* memory. Anyway, this legacy would only hit setups using pre-2.6.11
* kernel revisions. */
#define wrap_remap_vm_page(vma,from,to) \
-remap_pfn_range(vma,from,virt_to_phys((void *)__va_to_kva(to))
PAGE_SHIFT,PAGE_SHIFT,PAGE_SHARED)
+remap_pfn_range(vma,from,virt_to_phys((void *)__va_to_kva(to))
PAGE_SHIFT,PAGE_SHIFT,vma-vm_page_prot)
#define wrap_remap_io_page_range(vma,from,to,size,prot) ({ \
(vma)-vm_page_prot = pgprot_noncached((vma)-vm_page_prot); \
/* Sets VM_RESERVED | VM_IO | VM_PFNMAP on the vma. */ \
@@ -236,7 +236,7 @@ unsigned long __va_to_kva(unsigned long
#else /* LINUX_VERSION_CODE KERNEL_VERSION(2,6,10) */
#define wrap_remap_vm_page(vma,from,to) ({ \
vma-vm_flags |= VM_RESERVED; \
-remap_page_range(from,virt_to_phys((void
*)__va_to_kva(to)),PAGE_SIZE,PAGE_SHARED); \
+remap_page_range(from,virt_to_phys((void
*)__va_to_kva(to)),PAGE_SIZE,vma-vm_page_prot); \
})
#define wrap_remap_io_page_range(vma,from,to,size,prot) ({ \
vma-vm_flags |= VM_RESERVED; \
@@ -248,7 +248,11 @@ unsigned long __va_to_kva(unsigned long
})
#endif /* LINUX_VERSION_CODE = KERNEL_VERSION(2,6,15) */
-#define wrap_switch_mm(prev,next,task) \
+#ifndef __GFP_BITS_SHIFT
+#define __GFP_BITS_SHIFT 20
+#endif
+
+#define wrap_switch_mm(prev,next,task) \
switch_mm(prev,next,task)
#define wrap_enter_lazy_tlb(mm,task) \
enter_lazy_tlb(mm,task)
Index: include/nucleus/heap.h
===
--- include/nucleus/heap.h(revision 3738)
+++ include/nucleus/heap.h(working copy)
@@ -57,6 +57,8 @@
#define XNHEAP_PCONT 1
#define XNHEAP_PLIST 2
+#define XNHEAP_GFP_NONCACHED (1 __GFP_BITS_SHIFT)
+
typedef struct xnextent {
xnholder_t link;
Index: ksrc/skins/native/heap.c
===
--- ksrc/skins/native/heap.c (revision 3738)
+++ ksrc/skins/native/heap.c (working copy)
@@ -205,6 +205,10 @@ static void __heap_flush_private(xnheap_
* operations with I/O devices. The physical address of the
* heap can be obtained by a call to rt_heap_inquire().
*
+ * - H_NONCACHED causes the heap not to be cached. This is necessary on
+ * platforms such as ARM to share a heap between kernel and user-space.
+ * Note that this flag is not compatible with the H_DMA flag.
+ *
* @return 0 is returned upon success. Otherwise:
*
* - -EEXIST is returned if the @a name is already in use by some
@@ -260,7 +264,9 @@ int rt_heap_create(RT_HEAP *heap, const
err = xnheap_init_mapped(heap-heap_base,
heapsize,
- (mode H_DMA) ? GFP_DMA : 0);
[Xenomai-core] [Patch 1/7] Support for non cached memory mappings
In addition to support for non cached memory mappings, this patch implements
xnheap_init_mapped and xnheap_destroy_mapped in the !CONFIG_XENO_OPT_PERVASIVE
case. This avoids a lot of #ifdefs for users of these functions without
user-space support (posix skin shared memories, and the new semaphore heaps,
heaps where is allocated the memory used for storing semaphores counters and
mutexes owner fields).
---
include/asm-generic/wrappers.h | 12 +---
include/native/heap.h |1
include/nucleus/heap.h |2 +
ksrc/nucleus/heap.c| 55 +++--
ksrc/skins/native/heap.c |8 +
5 files changed, 66 insertions(+), 12 deletions(-)
Index: include/native/heap.h
===
--- include/native/heap.h (revision 3738)
+++ include/native/heap.h (working copy)
@@ -33,6 +33,7 @@
#define H_MAPPABLE 0x200 /* Memory is mappable to user-space. */
#define H_SINGLE 0x400 /* Manage as single-block area. */
#define H_SHARED (H_MAPPABLE|H_SINGLE) /* I.e. shared memory segment. */
+#define H_NONCACHED 0x800
/** Structure containing heap-information useful to users.
*
Index: include/asm-generic/wrappers.h
===
--- include/asm-generic/wrappers.h (revision 3738)
+++ include/asm-generic/wrappers.h (working copy)
@@ -62,7 +62,7 @@ unsigned long __va_to_kva(unsigned long
#define wrap_remap_vm_page(vma,from,to) ({ \
vma-vm_flags |= VM_RESERVED; \
-remap_page_range(from,virt_to_phys((void
*)__va_to_kva(to)),PAGE_SIZE,PAGE_SHARED); \
+remap_page_range(from,virt_to_phys((void
*)__va_to_kva(to)),PAGE_SIZE,vma-vm_page_prot); \
})
#define wrap_remap_io_page_range(vma,from,to,size,prot) ({ \
vma-vm_flags |= VM_RESERVED; \
@@ -223,7 +223,7 @@ unsigned long __va_to_kva(unsigned long
* memory. Anyway, this legacy would only hit setups using pre-2.6.11
* kernel revisions. */
#define wrap_remap_vm_page(vma,from,to) \
-remap_pfn_range(vma,from,virt_to_phys((void *)__va_to_kva(to))
PAGE_SHIFT,PAGE_SHIFT,PAGE_SHARED)
+remap_pfn_range(vma,from,virt_to_phys((void *)__va_to_kva(to))
PAGE_SHIFT,PAGE_SHIFT,vma-vm_page_prot)
#define wrap_remap_io_page_range(vma,from,to,size,prot) ({\
(vma)-vm_page_prot = pgprot_noncached((vma)-vm_page_prot); \
/* Sets VM_RESERVED | VM_IO | VM_PFNMAP on the vma. */ \
@@ -236,7 +236,7 @@ unsigned long __va_to_kva(unsigned long
#else /* LINUX_VERSION_CODE KERNEL_VERSION(2,6,10) */
#define wrap_remap_vm_page(vma,from,to) ({ \
vma-vm_flags |= VM_RESERVED; \
-remap_page_range(from,virt_to_phys((void
*)__va_to_kva(to)),PAGE_SIZE,PAGE_SHARED); \
+remap_page_range(from,virt_to_phys((void
*)__va_to_kva(to)),PAGE_SIZE,vma-vm_page_prot); \
})
#define wrap_remap_io_page_range(vma,from,to,size,prot) ({ \
vma-vm_flags |= VM_RESERVED;\
@@ -248,7 +248,11 @@ unsigned long __va_to_kva(unsigned long
})
#endif /* LINUX_VERSION_CODE = KERNEL_VERSION(2,6,15) */
-#define wrap_switch_mm(prev,next,task) \
+#ifndef __GFP_BITS_SHIFT
+#define __GFP_BITS_SHIFT 20
+#endif
+
+#define wrap_switch_mm(prev,next,task) \
switch_mm(prev,next,task)
#define wrap_enter_lazy_tlb(mm,task) \
enter_lazy_tlb(mm,task)
Index: include/nucleus/heap.h
===
--- include/nucleus/heap.h (revision 3738)
+++ include/nucleus/heap.h (working copy)
@@ -57,6 +57,8 @@
#define XNHEAP_PCONT 1
#define XNHEAP_PLIST 2
+#define XNHEAP_GFP_NONCACHED (1 __GFP_BITS_SHIFT)
+
typedef struct xnextent {
xnholder_t link;
Index: ksrc/skins/native/heap.c
===
--- ksrc/skins/native/heap.c(revision 3738)
+++ ksrc/skins/native/heap.c(working copy)
@@ -205,6 +205,10 @@ static void __heap_flush_private(xnheap_
* operations with I/O devices. The physical address of the
* heap can be obtained by a call to rt_heap_inquire().
*
+ * - H_NONCACHED causes the heap not to be cached. This is necessary on
+ * platforms such as ARM to share a heap between kernel and user-space.
+ * Note that this flag is not compatible with the H_DMA flag.
+ *
* @return 0 is returned upon success. Otherwise:
*
* - -EEXIST is returned if the @a name is already in use by some
@@ -260,7 +264,9 @@ int rt_heap_create(RT_HEAP *heap, const
err = xnheap_init_mapped(heap-heap_base,
heapsize,
-(mode H_DMA) ? GFP_DMA : 0);
+((mode H_DMA) ? GFP_DMA : 0)
+| ((mode H_NONCACHED) ?
+ XNHEAP_GFP_NONCACHED : 0));
if (err)
