| Olivier Deprez | 157378f | 2022-04-04 15:47:50 +0200 | [diff] [blame^] | 1 | // SPDX-License-Identifier: GPL-2.0 |
| 2 | |
| 3 | /* |
| 4 | * This file handles the architecture independent parts of process handling.. |
| 5 | */ |
| 6 | |
| 7 | #include <linux/compat.h> |
| 8 | #include <linux/errno.h> |
| 9 | #include <linux/kernel.h> |
| 10 | #include <linux/ptrace.h> |
| 11 | #include <linux/sched.h> |
| 12 | #include <linux/sched/task.h> |
| 13 | #include <linux/sched/task_stack.h> |
| 14 | #include <linux/signal.h> |
| 15 | |
| 16 | #include "kernel.h" |
| 17 | |
| 18 | asmlinkage long sparc_fork(struct pt_regs *regs) |
| 19 | { |
| 20 | unsigned long orig_i1 = regs->u_regs[UREG_I1]; |
| 21 | long ret; |
| 22 | struct kernel_clone_args args = { |
| 23 | .exit_signal = SIGCHLD, |
| 24 | /* Reuse the parent's stack for the child. */ |
| 25 | .stack = regs->u_regs[UREG_FP], |
| 26 | }; |
| 27 | |
| 28 | ret = kernel_clone(&args); |
| 29 | |
| 30 | /* If we get an error and potentially restart the system |
| 31 | * call, we're screwed because copy_thread() clobbered |
| 32 | * the parent's %o1. So detect that case and restore it |
| 33 | * here. |
| 34 | */ |
| 35 | if ((unsigned long)ret >= -ERESTART_RESTARTBLOCK) |
| 36 | regs->u_regs[UREG_I1] = orig_i1; |
| 37 | |
| 38 | return ret; |
| 39 | } |
| 40 | |
| 41 | asmlinkage long sparc_vfork(struct pt_regs *regs) |
| 42 | { |
| 43 | unsigned long orig_i1 = regs->u_regs[UREG_I1]; |
| 44 | long ret; |
| 45 | |
| 46 | struct kernel_clone_args args = { |
| 47 | .flags = CLONE_VFORK | CLONE_VM, |
| 48 | .exit_signal = SIGCHLD, |
| 49 | /* Reuse the parent's stack for the child. */ |
| 50 | .stack = regs->u_regs[UREG_FP], |
| 51 | }; |
| 52 | |
| 53 | ret = kernel_clone(&args); |
| 54 | |
| 55 | /* If we get an error and potentially restart the system |
| 56 | * call, we're screwed because copy_thread() clobbered |
| 57 | * the parent's %o1. So detect that case and restore it |
| 58 | * here. |
| 59 | */ |
| 60 | if ((unsigned long)ret >= -ERESTART_RESTARTBLOCK) |
| 61 | regs->u_regs[UREG_I1] = orig_i1; |
| 62 | |
| 63 | return ret; |
| 64 | } |
| 65 | |
| 66 | asmlinkage long sparc_clone(struct pt_regs *regs) |
| 67 | { |
| 68 | unsigned long orig_i1 = regs->u_regs[UREG_I1]; |
| 69 | unsigned int flags = lower_32_bits(regs->u_regs[UREG_I0]); |
| 70 | long ret; |
| 71 | |
| 72 | struct kernel_clone_args args = { |
| 73 | .flags = (flags & ~CSIGNAL), |
| 74 | .exit_signal = (flags & CSIGNAL), |
| 75 | .tls = regs->u_regs[UREG_I3], |
| 76 | }; |
| 77 | |
| 78 | #ifdef CONFIG_COMPAT |
| 79 | if (test_thread_flag(TIF_32BIT)) { |
| 80 | args.pidfd = compat_ptr(regs->u_regs[UREG_I2]); |
| 81 | args.child_tid = compat_ptr(regs->u_regs[UREG_I4]); |
| 82 | args.parent_tid = compat_ptr(regs->u_regs[UREG_I2]); |
| 83 | } else |
| 84 | #endif |
| 85 | { |
| 86 | args.pidfd = (int __user *)regs->u_regs[UREG_I2]; |
| 87 | args.child_tid = (int __user *)regs->u_regs[UREG_I4]; |
| 88 | args.parent_tid = (int __user *)regs->u_regs[UREG_I2]; |
| 89 | } |
| 90 | |
| 91 | /* Did userspace give setup a separate stack for the child or are we |
| 92 | * reusing the parent's? |
| 93 | */ |
| 94 | if (regs->u_regs[UREG_I1]) |
| 95 | args.stack = regs->u_regs[UREG_I1]; |
| 96 | else |
| 97 | args.stack = regs->u_regs[UREG_FP]; |
| 98 | |
| 99 | ret = kernel_clone(&args); |
| 100 | |
| 101 | /* If we get an error and potentially restart the system |
| 102 | * call, we're screwed because copy_thread() clobbered |
| 103 | * the parent's %o1. So detect that case and restore it |
| 104 | * here. |
| 105 | */ |
| 106 | if ((unsigned long)ret >= -ERESTART_RESTARTBLOCK) |
| 107 | regs->u_regs[UREG_I1] = orig_i1; |
| 108 | |
| 109 | return ret; |
| 110 | } |