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Diffstat (limited to 'nuttx/arch/arm/src/armv7-m/vfork.S')
| -rw-r--r-- | nuttx/arch/arm/src/armv7-m/vfork.S | 142 |
1 files changed, 0 insertions, 142 deletions
diff --git a/nuttx/arch/arm/src/armv7-m/vfork.S b/nuttx/arch/arm/src/armv7-m/vfork.S deleted file mode 100644 index f36ff23aa..000000000 --- a/nuttx/arch/arm/src/armv7-m/vfork.S +++ /dev/null @@ -1,142 +0,0 @@ -/************************************************************************************ - * arch/arm/src/armv7-m/vfork.S - * - * 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. - * - ************************************************************************************/ - -/************************************************************************************ - * Included Files - ************************************************************************************/ - -#include <nuttx/config.h> - -#include "up_vfork.h" - -/************************************************************************************ - * Pre-processor Definitions - ************************************************************************************/ - -/************************************************************************************ - * Global Symbols - ************************************************************************************/ - - .syntax unified - .thumb - .file "vfork.S" - .globl up_vfork - -/************************************************************************************ - * Public Functions - ************************************************************************************/ - -/************************************************************************************ - * Name: vfork - * - * Description: - * The vfork() function has the same effect as fork(), except that the behavior is - * undefined if the process created by vfork() either modifies any data other than - * a variable of type pid_t used to store the return value from vfork(), or returns - * 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 up_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 - * - * Return: - * Upon successful completion, vfork() returns 0 to the child process and returns - * the process ID of the child process to the parent process. Otherwise, -1 is - * returned to the parent, no child process is created, and errno is set to - * indicate the error. - * - ************************************************************************************/ - - .thumb_func - .globl vfork - .type vfork, function -vfork: - /* Create a stack frame */ - - mov r0, sp /* Save the value of the stack on entry */ - sub sp, sp, #VFORK_SIZEOF /* Allocate the structure on the stack */ - - /* CPU registers */ - /* 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] - - /* Floating point registers (not yet) */ - - /* Then, call up_vfork(), passing it a pointer to the stack structure */ - - mov r0, sp - bl up_vfork - - /* Release the stack data and return the value returned by up_vfork */ - - ldr lr, [sp, #VFORK_LR_OFFSET] - add sp, sp, #VFORK_SIZEOF - bx lr - .size vfork, .-vfork - .end - |