.. | .. |
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5 | 5 | #include <linux/export.h> |
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6 | 6 | #include <asm/syscall.h> |
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7 | 7 | |
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8 | | -static int collect_syscall(struct task_struct *target, long *callno, |
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9 | | - unsigned long args[6], unsigned int maxargs, |
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10 | | - unsigned long *sp, unsigned long *pc) |
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| 8 | +static int collect_syscall(struct task_struct *target, struct syscall_info *info) |
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11 | 9 | { |
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| 10 | + unsigned long args[6] = { }; |
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12 | 11 | struct pt_regs *regs; |
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13 | 12 | |
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14 | 13 | if (!try_get_task_stack(target)) { |
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15 | 14 | /* Task has no stack, so the task isn't in a syscall. */ |
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16 | | - *sp = *pc = 0; |
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17 | | - *callno = -1; |
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| 15 | + memset(info, 0, sizeof(*info)); |
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| 16 | + info->data.nr = -1; |
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18 | 17 | return 0; |
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19 | 18 | } |
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20 | 19 | |
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.. | .. |
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24 | 23 | return -EAGAIN; |
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25 | 24 | } |
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26 | 25 | |
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27 | | - *sp = user_stack_pointer(regs); |
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28 | | - *pc = instruction_pointer(regs); |
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| 26 | + info->sp = user_stack_pointer(regs); |
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| 27 | + info->data.instruction_pointer = instruction_pointer(regs); |
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29 | 28 | |
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30 | | - *callno = syscall_get_nr(target, regs); |
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31 | | - if (*callno != -1L && maxargs > 0) |
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32 | | - syscall_get_arguments(target, regs, 0, maxargs, args); |
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| 29 | + info->data.nr = syscall_get_nr(target, regs); |
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| 30 | + if (info->data.nr != -1L) |
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| 31 | + syscall_get_arguments(target, regs, args); |
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| 32 | + |
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| 33 | + info->data.args[0] = args[0]; |
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| 34 | + info->data.args[1] = args[1]; |
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| 35 | + info->data.args[2] = args[2]; |
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| 36 | + info->data.args[3] = args[3]; |
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| 37 | + info->data.args[4] = args[4]; |
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| 38 | + info->data.args[5] = args[5]; |
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33 | 39 | |
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34 | 40 | put_task_stack(target); |
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35 | 41 | return 0; |
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.. | .. |
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38 | 44 | /** |
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39 | 45 | * task_current_syscall - Discover what a blocked task is doing. |
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40 | 46 | * @target: thread to examine |
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41 | | - * @callno: filled with system call number or -1 |
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42 | | - * @args: filled with @maxargs system call arguments |
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43 | | - * @maxargs: number of elements in @args to fill |
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44 | | - * @sp: filled with user stack pointer |
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45 | | - * @pc: filled with user PC |
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| 47 | + * @info: structure with the following fields: |
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| 48 | + * .sp - filled with user stack pointer |
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| 49 | + * .data.nr - filled with system call number or -1 |
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| 50 | + * .data.args - filled with @maxargs system call arguments |
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| 51 | + * .data.instruction_pointer - filled with user PC |
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46 | 52 | * |
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47 | | - * If @target is blocked in a system call, returns zero with *@callno |
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48 | | - * set to the the call's number and @args filled in with its arguments. |
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49 | | - * Registers not used for system call arguments may not be available and |
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50 | | - * it is not kosher to use &struct user_regset calls while the system |
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| 53 | + * If @target is blocked in a system call, returns zero with @info.data.nr |
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| 54 | + * set to the call's number and @info.data.args filled in with its |
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| 55 | + * arguments. Registers not used for system call arguments may not be available |
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| 56 | + * and it is not kosher to use &struct user_regset calls while the system |
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51 | 57 | * call is still in progress. Note we may get this result if @target |
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52 | 58 | * has finished its system call but not yet returned to user mode, such |
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53 | 59 | * as when it's stopped for signal handling or syscall exit tracing. |
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54 | 60 | * |
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55 | 61 | * If @target is blocked in the kernel during a fault or exception, |
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56 | | - * returns zero with *@callno set to -1 and does not fill in @args. |
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57 | | - * If so, it's now safe to examine @target using &struct user_regset |
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58 | | - * get() calls as long as we're sure @target won't return to user mode. |
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| 62 | + * returns zero with *@info.data.nr set to -1 and does not fill in |
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| 63 | + * @info.data.args. If so, it's now safe to examine @target using |
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| 64 | + * &struct user_regset get() calls as long as we're sure @target won't return |
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| 65 | + * to user mode. |
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59 | 66 | * |
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60 | 67 | * Returns -%EAGAIN if @target does not remain blocked. |
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61 | | - * |
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62 | | - * Returns -%EINVAL if @maxargs is too large (maximum is six). |
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63 | 68 | */ |
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64 | | -int task_current_syscall(struct task_struct *target, long *callno, |
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65 | | - unsigned long args[6], unsigned int maxargs, |
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66 | | - unsigned long *sp, unsigned long *pc) |
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| 69 | +int task_current_syscall(struct task_struct *target, struct syscall_info *info) |
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67 | 70 | { |
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68 | 71 | long state; |
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69 | 72 | unsigned long ncsw; |
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70 | 73 | |
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71 | | - if (unlikely(maxargs > 6)) |
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72 | | - return -EINVAL; |
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73 | | - |
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74 | 74 | if (target == current) |
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75 | | - return collect_syscall(target, callno, args, maxargs, sp, pc); |
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| 75 | + return collect_syscall(target, info); |
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76 | 76 | |
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77 | 77 | state = target->state; |
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78 | 78 | if (unlikely(!state)) |
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.. | .. |
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80 | 80 | |
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81 | 81 | ncsw = wait_task_inactive(target, state); |
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82 | 82 | if (unlikely(!ncsw) || |
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83 | | - unlikely(collect_syscall(target, callno, args, maxargs, sp, pc)) || |
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| 83 | + unlikely(collect_syscall(target, info)) || |
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84 | 84 | unlikely(wait_task_inactive(target, state) != ncsw)) |
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85 | 85 | return -EAGAIN; |
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86 | 86 | |
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