diff options
author | Dmitry Torokhov <dtor_core@ameritech.net> | 2006-04-02 00:08:05 -0500 |
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committer | Dmitry Torokhov <dtor_core@ameritech.net> | 2006-04-02 00:08:05 -0500 |
commit | 95d465fd750897ab32462a6702fbfe1b122cbbc0 (patch) | |
tree | 65c38b2f11c51bb6932e44dd6c92f15b0091abfe /kernel/futex_compat.c | |
parent | 642fde17dceceb56c7ba2762733ac688666ae657 (diff) | |
parent | 683aa4012f53b2ada0f430487e05d37b0d94e90a (diff) |
Manual merge with Linus.
Conflicts:
arch/powerpc/kernel/setup-common.c
drivers/input/keyboard/hil_kbd.c
drivers/input/mouse/hil_ptr.c
Diffstat (limited to 'kernel/futex_compat.c')
-rw-r--r-- | kernel/futex_compat.c | 144 |
1 files changed, 144 insertions, 0 deletions
diff --git a/kernel/futex_compat.c b/kernel/futex_compat.c new file mode 100644 index 00000000000..1ab6a0ea3d1 --- /dev/null +++ b/kernel/futex_compat.c @@ -0,0 +1,144 @@ +/* + * linux/kernel/futex_compat.c + * + * Futex compatibililty routines. + * + * Copyright 2006, Red Hat, Inc., Ingo Molnar + */ + +#include <linux/linkage.h> +#include <linux/compat.h> +#include <linux/futex.h> + +#include <asm/uaccess.h> + +/* + * Walk curr->robust_list (very carefully, it's a userspace list!) + * and mark any locks found there dead, and notify any waiters. + * + * We silently return on any sign of list-walking problem. + */ +void compat_exit_robust_list(struct task_struct *curr) +{ + struct compat_robust_list_head __user *head = curr->compat_robust_list; + struct robust_list __user *entry, *pending; + compat_uptr_t uentry, upending; + unsigned int limit = ROBUST_LIST_LIMIT; + compat_long_t futex_offset; + + /* + * Fetch the list head (which was registered earlier, via + * sys_set_robust_list()): + */ + if (get_user(uentry, &head->list.next)) + return; + entry = compat_ptr(uentry); + /* + * Fetch the relative futex offset: + */ + if (get_user(futex_offset, &head->futex_offset)) + return; + /* + * Fetch any possibly pending lock-add first, and handle it + * if it exists: + */ + if (get_user(upending, &head->list_op_pending)) + return; + pending = compat_ptr(upending); + if (upending) + handle_futex_death((void *)pending + futex_offset, curr); + + while (compat_ptr(uentry) != &head->list) { + /* + * A pending lock might already be on the list, so + * dont process it twice: + */ + if (entry != pending) + if (handle_futex_death((void *)entry + futex_offset, + curr)) + return; + + /* + * Fetch the next entry in the list: + */ + if (get_user(uentry, (compat_uptr_t *)&entry->next)) + return; + entry = compat_ptr(uentry); + /* + * Avoid excessively long or circular lists: + */ + if (!--limit) + break; + + cond_resched(); + } +} + +asmlinkage long +compat_sys_set_robust_list(struct compat_robust_list_head __user *head, + compat_size_t len) +{ + if (unlikely(len != sizeof(*head))) + return -EINVAL; + + current->compat_robust_list = head; + + return 0; +} + +asmlinkage long +compat_sys_get_robust_list(int pid, compat_uptr_t *head_ptr, + compat_size_t __user *len_ptr) +{ + struct compat_robust_list_head *head; + unsigned long ret; + + if (!pid) + head = current->compat_robust_list; + else { + struct task_struct *p; + + ret = -ESRCH; + read_lock(&tasklist_lock); + p = find_task_by_pid(pid); + if (!p) + goto err_unlock; + ret = -EPERM; + if ((current->euid != p->euid) && (current->euid != p->uid) && + !capable(CAP_SYS_PTRACE)) + goto err_unlock; + head = p->compat_robust_list; + read_unlock(&tasklist_lock); + } + + if (put_user(sizeof(*head), len_ptr)) + return -EFAULT; + return put_user(ptr_to_compat(head), head_ptr); + +err_unlock: + read_unlock(&tasklist_lock); + + return ret; +} + +asmlinkage long compat_sys_futex(u32 __user *uaddr, int op, u32 val, + struct compat_timespec __user *utime, u32 __user *uaddr2, + u32 val3) +{ + struct timespec t; + unsigned long timeout = MAX_SCHEDULE_TIMEOUT; + int val2 = 0; + + if (utime && (op == FUTEX_WAIT)) { + if (get_compat_timespec(&t, utime)) + return -EFAULT; + if (!timespec_valid(&t)) + return -EINVAL; + timeout = timespec_to_jiffies(&t) + 1; + } + if (op >= FUTEX_REQUEUE) + val2 = (int) (unsigned long) utime; + + return do_futex((unsigned long)uaddr, op, val, timeout, + (unsigned long)uaddr2, val2, val3); +} |