diff options
Diffstat (limited to 'arch/um/kernel/skas/process.c')
| -rw-r--r-- | arch/um/kernel/skas/process.c | 217 |
1 files changed, 217 insertions, 0 deletions
diff --git a/arch/um/kernel/skas/process.c b/arch/um/kernel/skas/process.c new file mode 100644 index 0000000..ae4fa71 --- /dev/null +++ b/arch/um/kernel/skas/process.c @@ -0,0 +1,217 @@ +/* + * Copyright (C) 2002 Jeff Dike (jdike@karaya.com) + * Licensed under the GPL + */ + +#include "linux/sched.h" +#include "linux/slab.h" +#include "linux/ptrace.h" +#include "linux/proc_fs.h" +#include "linux/file.h" +#include "linux/errno.h" +#include "linux/init.h" +#include "asm/uaccess.h" +#include "asm/atomic.h" +#include "kern_util.h" +#include "skas.h" +#include "os.h" +#include "user_util.h" +#include "tlb.h" +#include "kern.h" +#include "mode.h" +#include "registers.h" + +void switch_to_skas(void *prev, void *next) +{ + struct task_struct *from, *to; + + from = prev; + to = next; + + /* XXX need to check runqueues[cpu].idle */ + if(current->pid == 0) + switch_timers(0); + + switch_threads(&from->thread.mode.skas.switch_buf, + &to->thread.mode.skas.switch_buf); + + arch_switch_to_skas(current->thread.prev_sched, current); + + if(current->pid == 0) + switch_timers(1); +} + +extern void schedule_tail(struct task_struct *prev); + +/* This is called magically, by its address being stuffed in a jmp_buf + * and being longjmp-d to. + */ +void new_thread_handler(void) +{ + int (*fn)(void *), n; + void *arg; + + if(current->thread.prev_sched != NULL) + schedule_tail(current->thread.prev_sched); + current->thread.prev_sched = NULL; + + fn = current->thread.request.u.thread.proc; + arg = current->thread.request.u.thread.arg; + + /* The return value is 1 if the kernel thread execs a process, + * 0 if it just exits + */ + n = run_kernel_thread(fn, arg, ¤t->thread.exec_buf); + if(n == 1){ + /* Handle any immediate reschedules or signals */ + interrupt_end(); + userspace(¤t->thread.regs.regs); + } + else do_exit(0); +} + +void release_thread_skas(struct task_struct *task) +{ +} + +/* Called magically, see new_thread_handler above */ +void fork_handler(void) +{ + force_flush_all(); + if(current->thread.prev_sched == NULL) + panic("blech"); + + schedule_tail(current->thread.prev_sched); + + /* XXX: if interrupt_end() calls schedule, this call to + * arch_switch_to_skas isn't needed. We could want to apply this to + * improve performance. -bb */ + arch_switch_to_skas(current->thread.prev_sched, current); + + current->thread.prev_sched = NULL; + +/* Handle any immediate reschedules or signals */ + interrupt_end(); + + userspace(¤t->thread.regs.regs); +} + +int copy_thread_skas(int nr, unsigned long clone_flags, unsigned long sp, + unsigned long stack_top, struct task_struct * p, + struct pt_regs *regs) +{ + void (*handler)(void); + + if(current->thread.forking){ + memcpy(&p->thread.regs.regs.skas, ®s->regs.skas, + sizeof(p->thread.regs.regs.skas)); + REGS_SET_SYSCALL_RETURN(p->thread.regs.regs.skas.regs, 0); + if(sp != 0) REGS_SP(p->thread.regs.regs.skas.regs) = sp; + + handler = fork_handler; + + arch_copy_thread(¤t->thread.arch, &p->thread.arch); + } + else { + init_thread_registers(&p->thread.regs.regs); + p->thread.request.u.thread = current->thread.request.u.thread; + handler = new_thread_handler; + } + + new_thread(task_stack_page(p), &p->thread.mode.skas.switch_buf, + handler); + return(0); +} + +int new_mm(unsigned long stack) +{ + int fd; + + fd = os_open_file("/proc/mm", of_cloexec(of_write(OPENFLAGS())), 0); + if(fd < 0) + return(fd); + + if(skas_needs_stub) + map_stub_pages(fd, CONFIG_STUB_CODE, CONFIG_STUB_DATA, stack); + + return(fd); +} + +void init_idle_skas(void) +{ + cpu_tasks[current_thread->cpu].pid = os_getpid(); + default_idle(); +} + +extern void start_kernel(void); + +static int start_kernel_proc(void *unused) +{ + int pid; + + block_signals(); + pid = os_getpid(); + + cpu_tasks[0].pid = pid; + cpu_tasks[0].task = current; +#ifdef CONFIG_SMP + cpu_online_map = cpumask_of_cpu(0); +#endif + start_kernel(); + return(0); +} + +extern int userspace_pid[]; + +int start_uml_skas(void) +{ + if(proc_mm) + userspace_pid[0] = start_userspace(0); + + init_new_thread_signals(); + + init_task.thread.request.u.thread.proc = start_kernel_proc; + init_task.thread.request.u.thread.arg = NULL; + return(start_idle_thread(task_stack_page(&init_task), + &init_task.thread.mode.skas.switch_buf)); +} + +int external_pid_skas(struct task_struct *task) +{ +#warning Need to look up userspace_pid by cpu + return(userspace_pid[0]); +} + +int thread_pid_skas(struct task_struct *task) +{ +#warning Need to look up userspace_pid by cpu + return(userspace_pid[0]); +} + +void kill_off_processes_skas(void) +{ + if(proc_mm) +#warning need to loop over userspace_pids in kill_off_processes_skas + os_kill_ptraced_process(userspace_pid[0], 1); + else { + struct task_struct *p; + int pid, me; + + me = os_getpid(); + for_each_process(p){ + if(p->mm == NULL) + continue; + + pid = p->mm->context.skas.id.u.pid; + os_kill_ptraced_process(pid, 1); + } + } +} + +unsigned long current_stub_stack(void) +{ + if(current->mm == NULL) + return(0); + + return(current->mm->context.skas.id.stack); +} |