3c91735099
fork on UML has always somewhat subtle. The underlying cause has been the need to initialize a stack for the new process. The only portable way to initialize a new stack is to set it as the alternate signal stack and take a signal. The signal handler does whatever initialization is needed and jumps back to the original stack, where the fork processing is finished. The basic context switching mechanism is a jmp_buf for each process. You switch to a new process by longjmping to its jmp_buf. Now that UML has its own implementation of setjmp and longjmp, and I can poke around inside a jmp_buf without fear that libc will change the structure, a much simpler mechanism is possible. The jmpbuf can simply be initialized by hand. This eliminates - the need to set up and remove the alternate signal stack sending and handling a signal the signal blocking needed around the stack switching, since there is no stack switching setting up the jmp_buf needed to jump back to the original stack after the new one is set up In addition, since jmp_buf is now defined by UML, and not by libc, it can be embedded in the thread struct. This makes it unnecessary to have it exist on the stack, where it used to be. It also simplifies interfaces, since the switch jmp_buf used to be a void * inside the thread struct, and functions which took it as an argument needed to define a jmp_buf variable and assign it from the void *. Signed-off-by: Jeff Dike <jdike@addtoit.com> Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
342 lines
11 KiB
C
342 lines
11 KiB
C
/*
|
|
* Copyright (C) 2002 Jeff Dike (jdike@karaya.com)
|
|
* Licensed under the GPL
|
|
*/
|
|
|
|
#ifndef __OS_H__
|
|
#define __OS_H__
|
|
|
|
#include "uml-config.h"
|
|
#include "asm/types.h"
|
|
#include "../os/include/file.h"
|
|
#include "sysdep/ptrace.h"
|
|
#include "kern_util.h"
|
|
#include "skas/mm_id.h"
|
|
#include "irq_user.h"
|
|
#include "sysdep/tls.h"
|
|
#include "sysdep/archsetjmp.h"
|
|
|
|
#define OS_TYPE_FILE 1
|
|
#define OS_TYPE_DIR 2
|
|
#define OS_TYPE_SYMLINK 3
|
|
#define OS_TYPE_CHARDEV 4
|
|
#define OS_TYPE_BLOCKDEV 5
|
|
#define OS_TYPE_FIFO 6
|
|
#define OS_TYPE_SOCK 7
|
|
|
|
/* os_access() flags */
|
|
#define OS_ACC_F_OK 0 /* Test for existence. */
|
|
#define OS_ACC_X_OK 1 /* Test for execute permission. */
|
|
#define OS_ACC_W_OK 2 /* Test for write permission. */
|
|
#define OS_ACC_R_OK 4 /* Test for read permission. */
|
|
#define OS_ACC_RW_OK (OS_ACC_W_OK | OS_ACC_R_OK) /* Test for RW permission */
|
|
|
|
/*
|
|
* types taken from stat_file() in hostfs_user.c
|
|
* (if they are wrong here, they are wrong there...).
|
|
*/
|
|
struct uml_stat {
|
|
int ust_dev; /* device */
|
|
unsigned long long ust_ino; /* inode */
|
|
int ust_mode; /* protection */
|
|
int ust_nlink; /* number of hard links */
|
|
int ust_uid; /* user ID of owner */
|
|
int ust_gid; /* group ID of owner */
|
|
unsigned long long ust_size; /* total size, in bytes */
|
|
int ust_blksize; /* blocksize for filesystem I/O */
|
|
unsigned long long ust_blocks; /* number of blocks allocated */
|
|
unsigned long ust_atime; /* time of last access */
|
|
unsigned long ust_mtime; /* time of last modification */
|
|
unsigned long ust_ctime; /* time of last change */
|
|
};
|
|
|
|
struct openflags {
|
|
unsigned int r : 1;
|
|
unsigned int w : 1;
|
|
unsigned int s : 1; /* O_SYNC */
|
|
unsigned int c : 1; /* O_CREAT */
|
|
unsigned int t : 1; /* O_TRUNC */
|
|
unsigned int a : 1; /* O_APPEND */
|
|
unsigned int e : 1; /* O_EXCL */
|
|
unsigned int cl : 1; /* FD_CLOEXEC */
|
|
};
|
|
|
|
#define OPENFLAGS() ((struct openflags) { .r = 0, .w = 0, .s = 0, .c = 0, \
|
|
.t = 0, .a = 0, .e = 0, .cl = 0 })
|
|
|
|
static inline struct openflags of_read(struct openflags flags)
|
|
{
|
|
flags.r = 1;
|
|
return flags;
|
|
}
|
|
|
|
static inline struct openflags of_write(struct openflags flags)
|
|
{
|
|
flags.w = 1;
|
|
return flags;
|
|
}
|
|
|
|
static inline struct openflags of_rdwr(struct openflags flags)
|
|
{
|
|
return of_read(of_write(flags));
|
|
}
|
|
|
|
static inline struct openflags of_set_rw(struct openflags flags, int r, int w)
|
|
{
|
|
flags.r = r;
|
|
flags.w = w;
|
|
return flags;
|
|
}
|
|
|
|
static inline struct openflags of_sync(struct openflags flags)
|
|
{
|
|
flags.s = 1;
|
|
return flags;
|
|
}
|
|
|
|
static inline struct openflags of_create(struct openflags flags)
|
|
{
|
|
flags.c = 1;
|
|
return flags;
|
|
}
|
|
|
|
static inline struct openflags of_trunc(struct openflags flags)
|
|
{
|
|
flags.t = 1;
|
|
return flags;
|
|
}
|
|
|
|
static inline struct openflags of_append(struct openflags flags)
|
|
{
|
|
flags.a = 1;
|
|
return flags;
|
|
}
|
|
|
|
static inline struct openflags of_excl(struct openflags flags)
|
|
{
|
|
flags.e = 1;
|
|
return flags;
|
|
}
|
|
|
|
static inline struct openflags of_cloexec(struct openflags flags)
|
|
{
|
|
flags.cl = 1;
|
|
return flags;
|
|
}
|
|
|
|
/* file.c */
|
|
extern int os_stat_file(const char *file_name, struct uml_stat *buf);
|
|
extern int os_stat_fd(const int fd, struct uml_stat *buf);
|
|
extern int os_access(const char *file, int mode);
|
|
extern void os_print_error(int error, const char* str);
|
|
extern int os_get_exec_close(int fd, int *close_on_exec);
|
|
extern int os_set_exec_close(int fd, int close_on_exec);
|
|
extern int os_ioctl_generic(int fd, unsigned int cmd, unsigned long arg);
|
|
extern int os_window_size(int fd, int *rows, int *cols);
|
|
extern int os_new_tty_pgrp(int fd, int pid);
|
|
extern int os_get_ifname(int fd, char *namebuf);
|
|
extern int os_set_slip(int fd);
|
|
extern int os_set_owner(int fd, int pid);
|
|
extern int os_sigio_async(int master, int slave);
|
|
extern int os_mode_fd(int fd, int mode);
|
|
|
|
extern int os_seek_file(int fd, __u64 offset);
|
|
extern int os_open_file(char *file, struct openflags flags, int mode);
|
|
extern int os_read_file(int fd, void *buf, int len);
|
|
extern int os_write_file(int fd, const void *buf, int count);
|
|
extern int os_file_size(char *file, unsigned long long *size_out);
|
|
extern int os_file_modtime(char *file, unsigned long *modtime);
|
|
extern int os_pipe(int *fd, int stream, int close_on_exec);
|
|
extern int os_set_fd_async(int fd, int owner);
|
|
extern int os_clear_fd_async(int fd);
|
|
extern int os_set_fd_block(int fd, int blocking);
|
|
extern int os_accept_connection(int fd);
|
|
extern int os_create_unix_socket(char *file, int len, int close_on_exec);
|
|
extern int os_shutdown_socket(int fd, int r, int w);
|
|
extern void os_close_file(int fd);
|
|
extern int os_rcv_fd(int fd, int *helper_pid_out);
|
|
extern int create_unix_socket(char *file, int len, int close_on_exec);
|
|
extern int os_connect_socket(char *name);
|
|
extern int os_file_type(char *file);
|
|
extern int os_file_mode(char *file, struct openflags *mode_out);
|
|
extern int os_lock_file(int fd, int excl);
|
|
extern void os_flush_stdout(void);
|
|
extern int os_stat_filesystem(char *path, long *bsize_out,
|
|
long long *blocks_out, long long *bfree_out,
|
|
long long *bavail_out, long long *files_out,
|
|
long long *ffree_out, void *fsid_out,
|
|
int fsid_size, long *namelen_out,
|
|
long *spare_out);
|
|
extern int os_change_dir(char *dir);
|
|
extern int os_fchange_dir(int fd);
|
|
|
|
/* start_up.c */
|
|
extern void os_early_checks(void);
|
|
extern int can_do_skas(void);
|
|
extern void os_check_bugs(void);
|
|
extern void check_host_supports_tls(int *supports_tls, int *tls_min);
|
|
|
|
/* Make sure they are clear when running in TT mode. Required by
|
|
* SEGV_MAYBE_FIXABLE */
|
|
#ifdef UML_CONFIG_MODE_SKAS
|
|
#define clear_can_do_skas() do { ptrace_faultinfo = proc_mm = 0; } while (0)
|
|
#else
|
|
#define clear_can_do_skas() do {} while (0)
|
|
#endif
|
|
|
|
/* mem.c */
|
|
extern int create_mem_file(unsigned long long len);
|
|
|
|
/* process.c */
|
|
extern unsigned long os_process_pc(int pid);
|
|
extern int os_process_parent(int pid);
|
|
extern void os_stop_process(int pid);
|
|
extern void os_kill_process(int pid, int reap_child);
|
|
extern void os_kill_ptraced_process(int pid, int reap_child);
|
|
extern void os_usr1_process(int pid);
|
|
extern long os_ptrace_ldt(long pid, long addr, long data);
|
|
|
|
extern int os_getpid(void);
|
|
extern int os_getpgrp(void);
|
|
|
|
#ifdef UML_CONFIG_MODE_TT
|
|
extern void init_new_thread_stack(void *sig_stack, void (*usr1_handler)(int));
|
|
#endif
|
|
extern void init_new_thread_signals(void);
|
|
extern int run_kernel_thread(int (*fn)(void *), void *arg, void **jmp_ptr);
|
|
|
|
extern int os_map_memory(void *virt, int fd, unsigned long long off,
|
|
unsigned long len, int r, int w, int x);
|
|
extern int os_protect_memory(void *addr, unsigned long len,
|
|
int r, int w, int x);
|
|
extern int os_unmap_memory(void *addr, int len);
|
|
extern int os_drop_memory(void *addr, int length);
|
|
extern int can_drop_memory(void);
|
|
extern void os_flush_stdout(void);
|
|
|
|
/* tt.c
|
|
* for tt mode only (will be deleted in future...)
|
|
*/
|
|
extern void forward_ipi(int fd, int pid);
|
|
extern void kill_child_dead(int pid);
|
|
extern int wait_for_stop(int pid, int sig, int cont_type, void *relay);
|
|
extern int protect_memory(unsigned long addr, unsigned long len,
|
|
int r, int w, int x, int must_succeed);
|
|
extern void forward_pending_sigio(int target);
|
|
extern int start_fork_tramp(void *arg, unsigned long temp_stack,
|
|
int clone_flags, int (*tramp)(void *));
|
|
|
|
/* uaccess.c */
|
|
extern unsigned long __do_user_copy(void *to, const void *from, int n,
|
|
void **fault_addr, void **fault_catcher,
|
|
void (*op)(void *to, const void *from,
|
|
int n), int *faulted_out);
|
|
|
|
/* helper.c */
|
|
extern int run_helper(void (*pre_exec)(void *), void *pre_data, char **argv,
|
|
unsigned long *stack_out);
|
|
extern int run_helper_thread(int (*proc)(void *), void *arg,
|
|
unsigned int flags, unsigned long *stack_out,
|
|
int stack_order);
|
|
extern int helper_wait(int pid);
|
|
|
|
|
|
/* tls.c */
|
|
extern int os_set_thread_area(user_desc_t *info, int pid);
|
|
extern int os_get_thread_area(user_desc_t *info, int pid);
|
|
|
|
/* umid.c */
|
|
extern int umid_file_name(char *name, char *buf, int len);
|
|
extern int set_umid(char *name);
|
|
extern char *get_umid(void);
|
|
|
|
/* signal.c */
|
|
extern void set_sigstack(void *sig_stack, int size);
|
|
extern void remove_sigstack(void);
|
|
extern void set_handler(int sig, void (*handler)(int), int flags, ...);
|
|
extern int change_sig(int signal, int on);
|
|
extern void block_signals(void);
|
|
extern void unblock_signals(void);
|
|
extern int get_signals(void);
|
|
extern int set_signals(int enable);
|
|
extern void os_usr1_signal(int on);
|
|
|
|
/* trap.c */
|
|
extern void os_fill_handlinfo(struct kern_handlers h);
|
|
extern void do_longjmp(void *p, int val);
|
|
|
|
/* util.c */
|
|
extern void stack_protections(unsigned long address);
|
|
extern void task_protections(unsigned long address);
|
|
extern int raw(int fd);
|
|
extern void setup_machinename(char *machine_out);
|
|
extern void setup_hostinfo(void);
|
|
extern int setjmp_wrapper(void (*proc)(void *, void *), ...);
|
|
|
|
/* time.c */
|
|
#define BILLION (1000 * 1000 * 1000)
|
|
|
|
extern void switch_timers(int to_real);
|
|
extern void idle_sleep(int secs);
|
|
extern int set_interval(int is_virtual);
|
|
#ifdef CONFIG_MODE_TT
|
|
extern void enable_timer(void);
|
|
#endif
|
|
extern void disable_timer(void);
|
|
extern void uml_idle_timer(void);
|
|
extern unsigned long long os_nsecs(void);
|
|
|
|
/* skas/mem.c */
|
|
extern long run_syscall_stub(struct mm_id * mm_idp,
|
|
int syscall, unsigned long *args, long expected,
|
|
void **addr, int done);
|
|
extern long syscall_stub_data(struct mm_id * mm_idp,
|
|
unsigned long *data, int data_count,
|
|
void **addr, void **stub_addr);
|
|
extern int map(struct mm_id * mm_idp, unsigned long virt,
|
|
unsigned long len, int r, int w, int x, int phys_fd,
|
|
unsigned long long offset, int done, void **data);
|
|
extern int unmap(struct mm_id * mm_idp, void *addr, unsigned long len,
|
|
int done, void **data);
|
|
extern int protect(struct mm_id * mm_idp, unsigned long addr,
|
|
unsigned long len, int r, int w, int x, int done,
|
|
void **data);
|
|
|
|
/* skas/process.c */
|
|
extern int is_skas_winch(int pid, int fd, void *data);
|
|
extern int start_userspace(unsigned long stub_stack);
|
|
extern int copy_context_skas0(unsigned long stack, int pid);
|
|
extern void userspace(union uml_pt_regs *regs);
|
|
extern void map_stub_pages(int fd, unsigned long code,
|
|
unsigned long data, unsigned long stack);
|
|
extern void new_thread(void *stack, jmp_buf *buf, void (*handler)(void));
|
|
extern void switch_threads(jmp_buf *me, jmp_buf *you);
|
|
extern int start_idle_thread(void *stack, jmp_buf *switch_buf);
|
|
extern void initial_thread_cb_skas(void (*proc)(void *),
|
|
void *arg);
|
|
extern void halt_skas(void);
|
|
extern void reboot_skas(void);
|
|
|
|
/* irq.c */
|
|
extern int os_waiting_for_events(struct irq_fd *active_fds);
|
|
extern int os_create_pollfd(int fd, int events, void *tmp_pfd, int size_tmpfds);
|
|
extern void os_free_irq_by_cb(int (*test)(struct irq_fd *, void *), void *arg,
|
|
struct irq_fd *active_fds, struct irq_fd ***last_irq_ptr2);
|
|
extern void os_free_irq_later(struct irq_fd *active_fds,
|
|
int irq, void *dev_id);
|
|
extern int os_get_pollfd(int i);
|
|
extern void os_set_pollfd(int i, int fd);
|
|
extern void os_set_ioignore(void);
|
|
extern void init_irq_signals(int on_sigstack);
|
|
|
|
/* sigio.c */
|
|
extern int add_sigio_fd(int fd);
|
|
extern int ignore_sigio_fd(int fd);
|
|
extern void maybe_sigio_broken(int fd, int read);
|
|
|
|
/* skas/trap */
|
|
extern void sig_handler_common_skas(int sig, void *sc_ptr);
|
|
extern void user_signal(int sig, union uml_pt_regs *regs, int pid);
|
|
|
|
#endif
|