This initial vfork() check-in was a little pollyanna-ish

git-svn-id: svn://svn.code.sf.net/p/nuttx/code/trunk@5487 42af7a65-404d-4744-a932-0658087f49c3

18 files changed, 300 insertions, 72 deletions

diff --git a/nuttx/arch/arm/src/arm/up_vfork.S b/nuttx/arch/arm/src/arm/vfork.S
index 23e975c30..f0fe17f73 100644
--- a/nuttx/arch/arm/src/arm/up_vfork.S
+++ b/nuttx/arch/arm/src/arm/vfork.S
@@ -1,5 +1,5 @@
 /************************************************************************************
- * arch/arm/src/arm/up_vfork.S
+ * arch/arm/src/arm/vfork.S
  *
  *   Copyright (C) 2013 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
@@ -39,6 +39,8 @@
 
 #include <nuttx/config.h>
 
+#include "up_vfork.h"
+
 /************************************************************************************
  * Pre-processor Definitions
  ************************************************************************************/
@@ -47,8 +49,8 @@
  * Global Symbols
  ************************************************************************************/
 
-	.file	"up_vfork.S"
-	.globl	__vfork
+	.file	"vfork.S"
+	.globl	task_vfork
 
 /************************************************************************************
  * Public Functions
@@ -64,8 +66,25 @@
  *   from the function in which vfork() was called, or calls any other function before
  *   successfully calling _exit() or one of the exec family of functions. 
  *
- *   This thin layer implements vfork by simply calling __vfork() with the vfork()
- *   return address as an argument.
+ *   This thin layer implements vfork by simply calling task_vfork() with the vfork()
+ *   context as an argument.  The overall sequence is:
+ *
+ *   1) User code calls vfork().  vfork() collects context information and
+ *      transfers control up up_vfork().
+ *   2) up_vfork()and calls task_vforksetup().
+ *   3) task_vforksetup() allocates and configures the child task's TCB.  This
+ *      consists of:
+ *      - Allocation of the child task's TCB.
+ *      - Initialization of file descriptors and streams
+ *      - Configuration of environment variables
+ *      - Setup the intput parameters for the task.
+ *      - Initialization of the TCB (including call to up_initial_state()
+ *   4) up_vfork() provides any additional operating context. up_vfork must:
+ *      - Allocate and initialize the stack
+ *      - Initialize special values in any CPU registers that were not
+ *        already configured by up_initial_state()
+ *   5) up_vfork() then calls task_vforkstart()
+ *   6) task_vforkstart() then executes the child thread.
  *
  * Input Paremeters:
  *   None
@@ -81,12 +100,35 @@
 	.globl	vfork
 	.type	vfork, function
 vfork:
+	/* Create a stack frame */
+
+	mov		r0, sp					/* Save the value of the stack frame on entry */
+	sub		sp, sp, #VFORK_SIZEOF	/* Allocate the structure on the stack */
+
+	/* Save the volatile registers */
+
+	str		r4, [sp, #VFORK_R4_OFFSET]
+	str		r5, [sp, #VFORK_R5_OFFSET]
+	str		r6, [sp, #VFORK_R6_OFFSET]
+	str		r7, [sp, #VFORK_R7_OFFSET]
+	str		r8, [sp, #VFORK_R8_OFFSET]
+	str		r9, [sp, #VFORK_R9_OFFSET]
+	str		r10, [sp, #VFORK_R10_OFFSET]
+
+	/* Save the frame pointer, stack pointer, and return address */
+
+	str		fp, [sp, #VFORK_FP_OFFSET]
+	str		r0, [sp, #VFORK_SP_OFFSET]
+	str		lr, [sp, #VFORK_LR_OFFSET]
+
+	/* Then, call task_vfork(), passing it a pointer to the stack structure */
+
+	mov		r0, sp
+	bl		task_vfork
 
-    /* I know, I could have used the GCC's return address builtin and done this all
-     * in C.  But this works even if there is no builtin.
-     */
+	/* Release the stack data and return the value returned by task_vfork */
 
-	mov		r0, lr
-	b		__vfork
+	add		sp, sp, #VFORK_SIZEOF
+	mov		pc, lr
 	.size	vfork, .-vfork
 	.end
diff --git a/nuttx/arch/arm/src/armv7-m/up_vfork.S b/nuttx/arch/arm/src/armv7-m/vfork.S
index 65ccc4535..aceded400 100644
--- a/nuttx/arch/arm/src/armv7-m/up_vfork.S
+++ b/nuttx/arch/arm/src/armv7-m/vfork.S
@@ -1,5 +1,5 @@
 /************************************************************************************
- * arch/arm/src/armv7-m/up_vfork.S
+ * arch/arm/src/armv7-m/vfork.S
  *
  *   Copyright (C) 2013 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
@@ -39,6 +39,8 @@
 
 #include <nuttx/config.h>
 
+#include "up_vfork.h"
+
 /************************************************************************************
  * Pre-processor Definitions
  ************************************************************************************/
@@ -49,8 +51,8 @@
 
 	.syntax	unified
 	.thumb
-	.file	"up_vfork.S"
-	.globl	__vfork
+	.file	"vfork.S"
+	.globl	task_vfork
 
 /************************************************************************************
  * Public Functions
@@ -66,8 +68,25 @@
  *   from the function in which vfork() was called, or calls any other function before
  *   successfully calling _exit() or one of the exec family of functions. 
  *
- *   This thin layer implements vfork by simply calling __vfork() with the vfork()
- *   return address as an argument.
+ *   This thin layer implements vfork by simply calling task_vfork() with the vfork()
+ *   context as an argument.  The overall sequence is:
+ *
+ *   1) User code calls vfork().  vfork() collects context information and
+ *      transfers control up up_vfork().
+ *   2) up_vfork()and calls task_vforksetup().
+ *   3) task_vforksetup() allocates and configures the child task's TCB.  This
+ *      consists of:
+ *      - Allocation of the child task's TCB.
+ *      - Initialization of file descriptors and streams
+ *      - Configuration of environment variables
+ *      - Setup the intput parameters for the task.
+ *      - Initialization of the TCB (including call to up_initial_state()
+ *   4) up_vfork() provides any additional operating context. up_vfork must:
+ *      - Allocate and initialize the stack
+ *      - Initialize special values in any CPU registers that were not
+ *        already configured by up_initial_state()
+ *   5) up_vfork() then calls task_vforkstart()
+ *   6) task_vforkstart() then executes the child thread.
  *
  * Input Paremeters:
  *   None
@@ -84,13 +103,36 @@
 	.globl	vfork
 	.type	vfork, function
 vfork:
+	/* Create a stack frame */
+
+	mov		r0, sp					/* Save the value of the stack frame on entry */
+	sub		sp, sp, #VFORK_SIZEOF	/* Allocate the structure on the stack */
+
+	/* Save the volatile registers */
+
+	str		r4, [sp, #VFORK_R4_OFFSET]
+	str		r5, [sp, #VFORK_R5_OFFSET]
+	str		r6, [sp, #VFORK_R6_OFFSET]
+	str		r7, [sp, #VFORK_R7_OFFSET]
+	str		r8, [sp, #VFORK_R8_OFFSET]
+	str		r9, [sp, #VFORK_R9_OFFSET]
+	str		r10, [sp, #VFORK_R10_OFFSET]
+
+	/* Save the frame pointer, stack pointer, and return address */
+
+	str		fp, [sp, #VFORK_FP_OFFSET]
+	str		r0, [sp, #VFORK_SP_OFFSET]
+	str		lr, [sp, #VFORK_LR_OFFSET]
+
+	/* Then, call task_vfork(), passing it a pointer to the stack structure */
+
+	mov		r0, sp
+	bl		task_vfork
 
-    /* I know, I could have used the GCC's return address builtin and done this all
-     * in C.  But this works even if there is no builtin.
-     */
+	/* Release the stack data and return the value returned by task_vfork */
 
-	mov		r0, lr
-	b		__vfork
+	add		sp, sp, #VFORK_SIZEOF
+	bx		lr
 	.size	vfork, .-vfork
 	.end
 
diff --git a/nuttx/arch/arm/src/c5471/Make.defs b/nuttx/arch/arm/src/c5471/Make.defs
index 89c3aaf0b..afa73cf6c 100644
--- a/nuttx/arch/arm/src/c5471/Make.defs
+++ b/nuttx/arch/arm/src/c5471/Make.defs
@@ -35,14 +35,14 @@
 
 HEAD_ASRC	= up_nommuhead.S
 
-CMN_ASRCS	= up_saveusercontext.S up_fullcontextrestore.S up_vfork.S
+CMN_ASRCS	= up_saveusercontext.S up_fullcontextrestore.S vfork.S
 CMN_CSRCS	= up_allocateheap.c up_assert.c up_blocktask.c up_copystate.c \
 		  up_createstack.c up_dataabort.c up_mdelay.c up_udelay.c up_doirq.c \
 		  up_exit.c up_idle.c up_initialize.c up_initialstate.c \
 		  up_interruptcontext.c up_prefetchabort.c up_releasepending.c \
 		  up_releasestack.c up_reprioritizertr.c up_schedulesigaction.c \
 		  up_sigdeliver.c up_syscall.c up_unblocktask.c \
-		  up_undefinedinsn.c up_usestack.c up__vfork.c
+		  up_undefinedinsn.c up_usestack.c up_vfork.c
 
 ifeq ($(CONFIG_ELF),y)
 CMN_CSRCS += up_elf.c
diff --git a/nuttx/arch/arm/src/calypso/Make.defs b/nuttx/arch/arm/src/calypso/Make.defs
index 957d4e677..1a1d14869 100644
--- a/nuttx/arch/arm/src/calypso/Make.defs
+++ b/nuttx/arch/arm/src/calypso/Make.defs
@@ -39,14 +39,14 @@
 HEAD_ASRC = calypso_head.S
 
 CMN_ASRCS = up_saveusercontext.S up_fullcontextrestore.S up_vectors.S \
-            up_nommuhead.S up_vfork.S
+            up_nommuhead.S vfork.S
 CMN_CSRCS = up_allocateheap.c up_assert.c up_blocktask.c up_copystate.c \
             up_createstack.c up_dataabort.c up_mdelay.c up_udelay.c up_doirq.c \
             up_exit.c up_idle.c up_initialstate.c up_initialize.c \
             up_interruptcontext.c up_prefetchabort.c up_releasepending.c \
             up_releasestack.c up_reprioritizertr.c up_schedulesigaction.c \
             up_sigdeliver.c up_syscall.c up_unblocktask.c \
-            up_undefinedinsn.c up_usestack.c calypso_power.c up__vfork.c
+            up_undefinedinsn.c up_usestack.c calypso_power.c up_vfork.c
 
 ifeq ($(CONFIG_ELF),y)
 CMN_CSRCS += up_elf.c
diff --git a/nuttx/arch/arm/src/common/up__vfork.c b/nuttx/arch/arm/src/common/up_vfork.c
index a1081faa8..404abd1f8 100644
--- a/nuttx/arch/arm/src/common/up__vfork.c
+++ b/nuttx/arch/arm/src/common/up_vfork.c
@@ -1,5 +1,5 @@
 /****************************************************************************
- * arch/arm/src/common/up__vfork
+ * arch/arm/src/common/up_vfork.c
  *
  *   Copyright (C) 2013 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
@@ -39,10 +39,16 @@
 
 #include <nuttx/config.h>
 
-#include <sched.h>
+#include <stdint.h>
+#include <string.h>
+#include <assert.h>
+#include <errno.h>
 
 #include <nuttx/sched.h>
+#include <nuttx/arch.h>
+#include <arch/irq.h>
 
+#include "up_vfork.h"
 #include "os_internal.h"
 
 /****************************************************************************
@@ -75,7 +81,7 @@
  ****************************************************************************/
 
 /****************************************************************************
- * Name: __vfork
+ * Name: up_vfork
  *
  * Description:
  *   The vfork() function has the same effect as fork(), except that the
@@ -85,11 +91,29 @@
  *   called, or calls any other function before successfully calling _exit()
  *   or one of the exec family of functions. 
  *
- *   This thin layer starts the vfork child by simply spawning a new thread
- *   that begins at the return address of vfork().
+ *   The overall sequence is:
+ *
+ *   1) User code calls vfork().  vfork() collects context information and
+ *      transfers control up up_vfork().
+ *   2) up_vfork()and calls task_vforksetup().
+ *   3) task_vforksetup() allocates and configures the child task's TCB.  This
+ *      consists of:
+ *      - Allocation of the child task's TCB.
+ *      - Initialization of file descriptors and streams
+ *      - Configuration of environment variables
+ *      - Setup the intput parameters for the task.
+ *      - Initialization of the TCB (including call to up_initial_state()
+ *   4) up_vfork() provides any additional operating context. up_vfork must:
+ *      - Allocate and initialize the stack
+ *      - Initialize special values in any CPU registers that were not
+ *        already configured by up_initial_state()
+ *   5) up_vfork() then calls task_vforkstart()
+ *   6) task_vforkstart() then executes the child thread.
+ *
+ * task_vforkabort() may be called if an error occurs between steps 3 and 6.
  *
  * Input Paremeters:
- *   retaddr - The return address of vfork()
+ *   context - Caller context information saved by vfork()
  *
  * Return:
  *   Upon successful completion, vfork() returns 0 to the child process and
@@ -99,11 +123,22 @@
  *
  ****************************************************************************/
 
-pid_t __vfork(uint32_t retaddr)
+pid_t up_vfork(struct vfork_s *context)
 {
-  FAR _TCB *parent = (FAR _TCB *)g_readytorun.head;
+  _TCB *parent = (FAR _TCB *)g_readytorun.head;
+  _TCB *child;
   size_t stacksize;
-  int priority;
+  uint32_t newsp;
+  uint32_t stackutil;
+  int ret;
+
+  /* Allocate and initialize a TCB for the child task. */
+
+  child = task_vforksetup((start_t)context->lr);
+  if (!child)
+    {
+      return (pid_t)ERROR;
+    }
 
   /* Get the size of the parent task's stack.  Due to alignment operations,
    * the adjusted stack size may be smaller than the stack size originally
@@ -112,23 +147,50 @@ pid_t __vfork(uint32_t retaddr)
 
   stacksize = parent->adj_stack_size + CONFIG_STACK_ALIGNMENT - 1;
 
-  /* Get the current priority of the parent task */
+  /* Allocate the stack for the TCB */
 
-#ifdef CONFIG_PRIORITY_INHERITANCE
-  priority = parent->base_priority;  /* "Normal," unboosted priority */
-#else
-  priority = parent->sched_priority;  /* Current priority */
-#endif
+  ret = up_create_stack(child, stacksize);
+  if (ret != OK)
+    {
+      task_vforkabort(child, -ret);
+      return (pid_t)ERROR;
+    }
+
+  /* How much of the parent's stack was utilized? */
 
- /* Start the child thread at the vfork return address.  TASK_CREATE will
-  * return the PID of the new thread.  Otherwise a negative value will be
-  * returned and the errno will be set appropriately.
-  *
-  * When the registers are initialized, the return value in R0 should be
-  * cleared to zero, providing the indication to the newly started child
-  * thread.
+  DEBUGASSERT(parent->adj_stack_ptr > context->sp);
+  stackutil = (uint32_t)parent->adj_stack_ptr - context->sp;
+
+  /* Make some feeble effort to perserve the stack contents.  This is
+   * feeble because the stack surely contains invalid pointer and other
+   * content that will not work in the child context.  However, if the
+   * user follows all of the caveats of vfor() usage, even this feeble
+   * effort is overkill.
+   */
+
+  newsp = (uint32_t)child->adj_stack_ptr - stackutil;
+  memcpy((void *)newsp, (const void *)context->sp, stackutil);
+  
+ /* Update the stack pointer, frame pointer, and voltile registers.  When
+  * the child TCB was initialized, all of the values were set to zero.
+  * up_initial_state() altered a few values, but the return value in R0
+  * should be cleared to zero, providing the indication to the newly started
+  * child thread.
   */
 
-  return TASK_CREATE("init", priority, stacksize, (main_t)retaddr,
-                     (const char **)NULL);
+  child->xcp.regs[REG_R4]  = context->r4;  /* Volatile register r4 */
+  child->xcp.regs[REG_R5]  = context->r5;  /* Volatile register r5 */
+  child->xcp.regs[REG_R6]  = context->r6;  /* Volatile register r6 */
+  child->xcp.regs[REG_R7]  = context->r7;  /* Volatile register r7 */
+  child->xcp.regs[REG_R8]  = context->r8;  /* Volatile register r8 */
+  child->xcp.regs[REG_R9]  = context->r9;  /* Volatile register r9 */
+  child->xcp.regs[REG_R10] = context->r10; /* Volatile register r10 */
+  child->xcp.regs[REG_FP]  = context->fp;  /* Frame pointer */
+  child->xcp.regs[REG_SP]  = context->sp;  /* Stack pointer */
+
+  /* And, finally, start the child task.  On a failure, task_vforkstart()
+   * will discard the TCB by calling task_vforkabort().
+   */
+
+  return task_vforkstart(child);
 }
diff --git a/nuttx/arch/arm/src/common/up_vfork.h b/nuttx/arch/arm/src/common/up_vfork.h
new file mode 100644
index 000000000..a4505474a
--- /dev/null
+++ b/nuttx/arch/arm/src/common/up_vfork.h
@@ -0,0 +1,82 @@
+/****************************************************************************
+ * arch/arm/src/common/arm-vfork.h
+ *
+ *   Copyright (C) 2013 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <gnutt@nuttx.org>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name NuttX nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ****************************************************************************/
+
+#ifndef __ARCH_ARM_SRC_ARM_VFORK_H
+#define __ARCH_ARM_SRC_ARM_VFORK_H
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+
+/****************************************************************************
+ * Pre-processor Definitions
+ ****************************************************************************/
+
+#define VFORK_R4_OFFSET  (0*4)   /* Volatile register r4 */
+#define VFORK_R5_OFFSET  (1*4)   /* Volatile register r5 */
+#define VFORK_R6_OFFSET  (2*4)   /* Volatile register r6 */
+#define VFORK_R7_OFFSET  (3*4)   /* Volatile register r7 */
+#define VFORK_R8_OFFSET  (4*4)   /* Volatile register r8 */
+#define VFORK_R9_OFFSET  (5*4)   /* Volatile register r9 */
+#define VFORK_R10_OFFSET (6*4)   /* Volatile register r10 */
+#define VFORK_FP_OFFSET  (7*4)   /* Frame pointer */
+#define VFORK_SP_OFFSET  (8*4)   /* Stack pointer*/
+#define VFORK_LR_OFFSET  (9*4)   /* Return address*/
+
+#define VFORK_SIZEOF     (10*4)
+
+/****************************************************************************
+ * Public Types
+ ****************************************************************************/
+
+#ifndef __ASSEMBLY__
+struct vfork_s
+{
+  uint32_t r4;   /* Volatile register r4 */
+  uint32_t r5;   /* Volatile register r5 */
+  uint32_t r6;   /* Volatile register r6 */
+  uint32_t r7;   /* Volatile register r7 */
+  uint32_t r8;   /* Volatile register r8 */
+  uint32_t r9;   /* Volatile register r9 */
+  uint32_t r10;  /* Volatile register r10 */
+  uint32_t fp;   /* Frame pointer */
+  uint32_t sp;   /* Stack pointer*/
+  uint32_t lr;   /* Return address*/
+};
+#endif
+
+#endif /* __ARCH_ARM_SRC_ARM_VFORK_H */
diff --git a/nuttx/arch/arm/src/dm320/Make.defs b/nuttx/arch/arm/src/dm320/Make.defs
index 52e65c0e8..651d9fea9 100644
--- a/nuttx/arch/arm/src/dm320/Make.defs
+++ b/nuttx/arch/arm/src/dm320/Make.defs
@@ -36,14 +36,14 @@
 HEAD_ASRC	= up_head.S
 
 CMN_ASRCS	= up_cache.S up_fullcontextrestore.S up_saveusercontext.S \
-		  up_vectors.S up_vectoraddrexcptn.S up_vectortab.S up_vfork.S
+		  up_vectors.S up_vectoraddrexcptn.S up_vectortab.S vfork.S
 CMN_CSRCS	= up_assert.c up_blocktask.c up_copystate.c up_createstack.c \
 		  up_dataabort.c up_mdelay.c up_udelay.c up_exit.c up_idle.c \
 		  up_initialize.c up_initialstate.c up_interruptcontext.c \
 		  up_prefetchabort.c up_releasepending.c up_releasestack.c \
 		  up_reprioritizertr.c up_schedulesigaction.c \
 		  up_sigdeliver.c up_syscall.c up_unblocktask.c \
-		  up_undefinedinsn.c up_usestack.c up__vfork.c
+		  up_undefinedinsn.c up_usestack.c up_vfork.c
 
 ifeq ($(CONFIG_ELF),y)
 CMN_CSRCS += up_elf.c
diff --git a/nuttx/arch/arm/src/imx/Make.defs b/nuttx/arch/arm/src/imx/Make.defs
index a7c0ceebd..3cea29b9b 100644
--- a/nuttx/arch/arm/src/imx/Make.defs
+++ b/nuttx/arch/arm/src/imx/Make.defs
@@ -36,14 +36,14 @@
 HEAD_ASRC	= up_head.S
 
 CMN_ASRCS	= up_cache.S up_fullcontextrestore.S up_saveusercontext.S \
-		  up_vectors.S up_vectoraddrexcptn.S up_vectortab.S up_vfork.S
+		  up_vectors.S up_vectoraddrexcptn.S up_vectortab.S vfork.S
 CMN_CSRCS	= up_assert.c up_blocktask.c up_copystate.c up_createstack.c \
 		  up_dataabort.c up_mdelay.c up_udelay.c up_exit.c up_idle.c \
 		  up_initialize.c up_initialstate.c up_interruptcontext.c \
 		  up_prefetchabort.c up_releasepending.c up_releasestack.c \
 		  up_reprioritizertr.c up_schedulesigaction.c \
 		  up_sigdeliver.c up_syscall.c up_unblocktask.c \
-		  up_undefinedinsn.c up_usestack.c up__vfork.c
+		  up_undefinedinsn.c up_usestack.c up_vfork.c
 
 ifeq ($(CONFIG_ELF),y)
 CMN_CSRCS += up_elf.c
diff --git a/nuttx/arch/arm/src/kinetis/Make.defs b/nuttx/arch/arm/src/kinetis/Make.defs
index bad2946e2..e41746547 100644
--- a/nuttx/arch/arm/src/kinetis/Make.defs
+++ b/nuttx/arch/arm/src/kinetis/Make.defs
@@ -40,7 +40,7 @@ HEAD_ASRC	= kinetis_vectors.S
 # Common ARM and Cortex-M3 files
 
 CMN_ASRCS	= up_saveusercontext.S up_fullcontextrestore.S up_switchcontext.S \
-			  up_vfork.S
+			  vfork.S
 CMN_CSRCS	= up_allocateheap.c up_assert.c up_blocktask.c up_copystate.c \
 			  up_createstack.c up_mdelay.c up_udelay.c up_exit.c up_initialize.c \
 			  up_memfault.c up_initialstate.c up_interruptcontext.c \
@@ -48,7 +48,7 @@ CMN_CSRCS	= up_allocateheap.c up_assert.c up_blocktask.c up_copystate.c \
 			  up_releasestack.c up_reprioritizertr.c up_schedulesigaction.c \
 			  up_releasepending.c up_sigdeliver.c up_unblocktask.c up_usestack.c \
 			  up_doirq.c up_hardfault.c up_svcall.c up_checkstack.c \
-			  up__vfork.c
+			  up_vfork.c
 
 ifeq ($(CONFIG_ARCH_MEMCPY),y)
 CMN_ASRCS	+= up_memcpy.S
diff --git a/nuttx/arch/arm/src/lm3s/Make.defs b/nuttx/arch/arm/src/lm3s/Make.defs
index c745e1953..66b8f5658 100644
--- a/nuttx/arch/arm/src/lm3s/Make.defs
+++ b/nuttx/arch/arm/src/lm3s/Make.defs
@@ -36,7 +36,7 @@
 HEAD_ASRC	= lm3s_vectors.S
 
 CMN_ASRCS	= up_saveusercontext.S up_fullcontextrestore.S up_switchcontext.S \
-			  up_vfork.S
+			  vfork.S
 CMN_CSRCS	= up_allocateheap.c up_assert.c up_blocktask.c up_copystate.c \
 			  up_createstack.c up_mdelay.c up_udelay.c up_exit.c \
 			  up_idle.c up_initialize.c up_initialstate.c up_interruptcontext.c \
@@ -44,7 +44,7 @@ CMN_CSRCS	= up_allocateheap.c up_assert.c up_blocktask.c up_copystate.c \
 			  up_releasepending.c up_releasestack.c up_reprioritizertr.c \
 			  up_schedulesigaction.c up_sigdeliver.c up_unblocktask.c \
 			  up_usestack.c up_doirq.c up_hardfault.c up_svcall.c \
-			  up__vfork.c
+			  up_vfork.c
 
 ifeq ($(CONFIG_ARCH_MEMCPY),y)
 CMN_ASRCS	+= up_memcpy.S
diff --git a/nuttx/arch/arm/src/lpc17xx/Make.defs b/nuttx/arch/arm/src/lpc17xx/Make.defs
index 1ea0183a1..ed05fff95 100644
--- a/nuttx/arch/arm/src/lpc17xx/Make.defs
+++ b/nuttx/arch/arm/src/lpc17xx/Make.defs
@@ -40,14 +40,14 @@ HEAD_ASRC	= lpc17_vectors.S
 # Common ARM and Cortex-M3 files
 
 CMN_ASRCS	= up_saveusercontext.S up_fullcontextrestore.S up_switchcontext.S \
-			  up_vfork.S
+			  vfork.S
 CMN_CSRCS	= up_assert.c up_blocktask.c up_copystate.c up_createstack.c \
 			  up_mdelay.c up_udelay.c up_exit.c up_initialize.c up_memfault.c \
 			  up_initialstate.c up_interruptcontext.c up_modifyreg8.c \
 			  up_modifyreg16.c up_modifyreg32.c up_releasepending.c \
 			  up_releasestack.c up_reprioritizertr.c up_schedulesigaction.c \
 			  up_sigdeliver.c up_unblocktask.c up_usestack.c up_doirq.c \
-			  up_hardfault.c up_svcall.c up_checkstack.c up__vfork.c
+			  up_hardfault.c up_svcall.c up_checkstack.c up_vfork.c
 
 ifeq ($(CONFIG_ARCH_MEMCPY),y)
 CMN_ASRCS	+= up_memcpy.S
diff --git a/nuttx/arch/arm/src/lpc214x/Make.defs b/nuttx/arch/arm/src/lpc214x/Make.defs
index 6821d512b..34713b008 100644
--- a/nuttx/arch/arm/src/lpc214x/Make.defs
+++ b/nuttx/arch/arm/src/lpc214x/Make.defs
@@ -36,13 +36,13 @@
 HEAD_ASRC	= lpc214x_head.S
 
 CMN_ASRCS	= up_saveusercontext.S up_fullcontextrestore.S up_vectors.S \
-			  up_vfork.S
+			  vfork.S
 CMN_CSRCS	= up_allocateheap.c up_assert.c up_blocktask.c up_copystate.c \
 		  up_createstack.c up_dataabort.c up_mdelay.c up_udelay.c \
 		  up_exit.c up_idle.c up_initialize.c up_initialstate.c \
 		  up_interruptcontext.c up_prefetchabort.c up_releasepending.c \
 		  up_releasestack.c up_reprioritizertr.c up_syscall.c up_unblocktask.c \
-		  up_undefinedinsn.c up_usestack.c up_lowputs.c up__vfork.c
+		  up_undefinedinsn.c up_usestack.c up_lowputs.c up_vfork.c
 
 ifneq ($(CONFIG_DISABLE_SIGNALS),y)
 CMN_CSRCS	+= up_schedulesigaction.c up_sigdeliver.c
diff --git a/nuttx/arch/arm/src/lpc2378/Make.defs b/nuttx/arch/arm/src/lpc2378/Make.defs
index 3d3c15926..cfd9dc79f 100644
--- a/nuttx/arch/arm/src/lpc2378/Make.defs
+++ b/nuttx/arch/arm/src/lpc2378/Make.defs
@@ -41,13 +41,13 @@
 HEAD_ASRC	= lpc23xx_head.S
 
 CMN_ASRCS	= up_saveusercontext.S up_fullcontextrestore.S up_vectors.S \
-			  up_vfork.S
+			  vfork.S
 CMN_CSRCS	= up_allocateheap.c up_assert.c up_blocktask.c up_copystate.c \
 			  up_createstack.c up_dataabort.c up_mdelay.c up_udelay.c \
 			  up_exit.c up_idle.c up_initialize.c up_initialstate.c \
 			  up_interruptcontext.c up_prefetchabort.c up_releasepending.c \
 			  up_releasestack.c up_reprioritizertr.c up_syscall.c up_unblocktask.c \
-			  up_undefinedinsn.c up_usestack.c up_lowputs.c up__vfork.c
+			  up_undefinedinsn.c up_usestack.c up_lowputs.c up_vfork.c
 
 ifneq ($(CONFIG_DISABLE_SIGNALS),y)
 CMN_CSRCS	+= up_schedulesigaction.c up_sigdeliver.c
diff --git a/nuttx/arch/arm/src/lpc31xx/Make.defs b/nuttx/arch/arm/src/lpc31xx/Make.defs
index b3a9746b4..4e6f69299 100644
--- a/nuttx/arch/arm/src/lpc31xx/Make.defs
+++ b/nuttx/arch/arm/src/lpc31xx/Make.defs
@@ -36,7 +36,7 @@
 HEAD_ASRC	= up_head.S
 
 CMN_ASRCS	= up_cache.S up_fullcontextrestore.S up_saveusercontext.S \
-		  up_vectors.S up_vectoraddrexcptn.S up_vectortab.S up_vfork.S
+		  up_vectors.S up_vectoraddrexcptn.S up_vectortab.S vfork.S
 CMN_CSRCS	= up_assert.c up_blocktask.c up_copystate.c up_createstack.c \
 		  up_dataabort.c up_mdelay.c up_udelay.c up_exit.c up_idle.c \
 		  up_initialize.c up_initialstate.c up_interruptcontext.c \
@@ -44,7 +44,7 @@ CMN_CSRCS	= up_assert.c up_blocktask.c up_copystate.c up_createstack.c \
 		  up_prefetchabort.c up_releasepending.c up_releasestack.c \
 		  up_reprioritizertr.c up_schedulesigaction.c \
 		  up_sigdeliver.c up_syscall.c up_unblocktask.c \
-		  up_undefinedinsn.c up_usestack.c up__vfork.c
+		  up_undefinedinsn.c up_usestack.c up_vfork.c
 
 ifeq ($(CONFIG_PAGING),y)
 CMN_CSRCS	+= up_pginitialize.c up_checkmapping.c up_allocpage.c up_va2pte.c
diff --git a/nuttx/arch/arm/src/lpc43xx/Make.defs b/nuttx/arch/arm/src/lpc43xx/Make.defs
index 211f9bee3..9674196c5 100644
--- a/nuttx/arch/arm/src/lpc43xx/Make.defs
+++ b/nuttx/arch/arm/src/lpc43xx/Make.defs
@@ -36,7 +36,7 @@
 HEAD_ASRC  =
 
 CMN_ASRCS  = up_saveusercontext.S up_fullcontextrestore.S up_switchcontext.S
-CMN_ASRCS += up_vfork.S
+CMN_ASRCS += vfork.S
 
 CMN_CSRCS  = up_assert.c up_blocktask.c up_copystate.c
 CMN_CSRCS += up_createstack.c up_mdelay.c up_udelay.c up_exit.c
@@ -44,7 +44,7 @@ CMN_CSRCS += up_initialize.c up_initialstate.c up_interruptcontext.c
 CMN_CSRCS += up_memfault.c up_modifyreg8.c up_modifyreg16.c up_modifyreg32.c
 CMN_CSRCS += up_releasepending.c up_releasestack.c up_reprioritizertr.c
 CMN_CSRCS += up_schedulesigaction.c up_sigdeliver.c up_unblocktask.c
-CMN_CSRCS += up_usestack.c up_doirq.c up_hardfault.c up_svcall.c up__vfork.c
+CMN_CSRCS += up_usestack.c up_doirq.c up_hardfault.c up_svcall.c up_vfork.c
 
 ifeq ($(CONFIG_ARMV7M_CMNVECTOR),y)
 CMN_ASRCS += up_exception.S
diff --git a/nuttx/arch/arm/src/sam3u/Make.defs b/nuttx/arch/arm/src/sam3u/Make.defs
index 4682ea83d..58047af21 100644
--- a/nuttx/arch/arm/src/sam3u/Make.defs
+++ b/nuttx/arch/arm/src/sam3u/Make.defs
@@ -40,14 +40,14 @@ HEAD_ASRC	= sam3u_vectors.S
 # Common ARM and Cortex-M3 files
 
 CMN_ASRCS	= up_saveusercontext.S up_fullcontextrestore.S up_switchcontext.S \
-			  up_vfork.S
+			  vfork.S
 CMN_CSRCS	= up_assert.c up_blocktask.c up_copystate.c up_createstack.c \
 			  up_mdelay.c up_udelay.c up_exit.c up_idle.c up_initialize.c \
 			  up_initialstate.c up_interruptcontext.c up_memfault.c up_modifyreg8.c \
 			  up_modifyreg16.c up_modifyreg32.c up_releasepending.c \
 			  up_releasestack.c up_reprioritizertr.c up_schedulesigaction.c \
 			  up_sigdeliver.c up_unblocktask.c up_usestack.c up_doirq.c \
-			  up_hardfault.c up_svcall.c up__vfork.c
+			  up_hardfault.c up_svcall.c up_vfork.c
 
 # Configuration-dependent common files
 
diff --git a/nuttx/arch/arm/src/stm32/Make.defs b/nuttx/arch/arm/src/stm32/Make.defs
index 89c291791..fd19e3bf6 100644
--- a/nuttx/arch/arm/src/stm32/Make.defs
+++ b/nuttx/arch/arm/src/stm32/Make.defs
@@ -40,7 +40,7 @@ HEAD_ASRC	= stm32_vectors.S
 endif
 
 CMN_ASRCS	= up_saveusercontext.S up_fullcontextrestore.S up_switchcontext.S \
-			  up_vfork.S
+			  vfork.S
 CMN_CSRCS	= up_assert.c up_blocktask.c up_copystate.c \
 			  up_createstack.c up_mdelay.c up_udelay.c up_exit.c \
 			  up_initialize.c up_initialstate.c up_interruptcontext.c \
@@ -48,7 +48,7 @@ CMN_CSRCS	= up_assert.c up_blocktask.c up_copystate.c \
 			  up_releasepending.c up_releasestack.c up_reprioritizertr.c \
 			  up_schedulesigaction.c up_sigdeliver.c up_systemreset.c \
 			  up_unblocktask.c up_usestack.c up_doirq.c up_hardfault.c \
-			  up_svcall.c up__vfork.c
+			  up_svcall.c up_vfork.c
 
 ifeq ($(CONFIG_ARMV7M_CMNVECTOR),y)
 CMN_ASRCS	+= up_exception.S
diff --git a/nuttx/arch/arm/src/str71x/Make.defs b/nuttx/arch/arm/src/str71x/Make.defs
index 3612950a6..bde5ca003 100644
--- a/nuttx/arch/arm/src/str71x/Make.defs
+++ b/nuttx/arch/arm/src/str71x/Make.defs
@@ -36,13 +36,13 @@
 HEAD_ASRC	= str71x_head.S
 
 CMN_ASRCS	= up_saveusercontext.S up_fullcontextrestore.S up_vectors.S \
-			  up_vfork.S
+			  vfork.S
 CMN_CSRCS	= up_allocateheap.c up_assert.c up_blocktask.c up_copystate.c \
 			  up_createstack.c up_dataabort.c up_mdelay.c up_udelay.c \
 			  up_exit.c up_idle.c up_initialize.c up_initialstate.c \
 			  up_interruptcontext.c up_prefetchabort.c up_releasepending.c \
 			  up_releasestack.c up_reprioritizertr.c up_syscall.c up_unblocktask.c \
-			  up_undefinedinsn.c up_usestack.c up_lowputs.c up__vfork.c
+			  up_undefinedinsn.c up_usestack.c up_lowputs.c up_vfork.c
 
 ifneq ($(CONFIG_DISABLE_SIGNALS),y)
 CMN_CSRCS	+= up_schedulesigaction.c up_sigdeliver.c