diff options
Diffstat (limited to 'sys/compat/linux/linux_futex.c')
| -rw-r--r-- | sys/compat/linux/linux_futex.c | 161 |
1 files changed, 161 insertions, 0 deletions
diff --git a/sys/compat/linux/linux_futex.c b/sys/compat/linux/linux_futex.c index f4423b4..043962e 100644 --- a/sys/compat/linux/linux_futex.c +++ b/sys/compat/linux/linux_futex.c @@ -45,8 +45,11 @@ __KERNEL_RCSID(1, "$NetBSD: linux_futex.c,v 1.7 2006/07/24 19:01:49 manu Exp $") #include <sys/systm.h> #include <sys/proc.h> #include <sys/queue.h> +#include <sys/imgact.h> #include <sys/lock.h> #include <sys/mutex.h> +#include <sys/priv.h> +#include <sys/sched.h> #include <sys/sx.h> #include <sys/malloc.h> @@ -57,6 +60,7 @@ __KERNEL_RCSID(1, "$NetBSD: linux_futex.c,v 1.7 2006/07/24 19:01:49 manu Exp $") #include <machine/../linux/linux.h> #include <machine/../linux/linux_proto.h> #endif +#include <compat/linux/linux_emul.h> #include <compat/linux/linux_futex.h> struct futex; @@ -533,3 +537,160 @@ futex_atomic_op(struct thread *td, int encoded_op, caddr_t uaddr) return (-ENOSYS); } } + +int +linux_set_robust_list(struct thread *td, struct linux_set_robust_list_args *args) +{ + struct linux_emuldata *em; + +#ifdef DEBUG + if (ldebug(set_robust_list)) + printf(ARGS(set_robust_list, "")); +#endif + if (args->len != sizeof(struct linux_robust_list_head)) + return (EINVAL); + + em = em_find(td->td_proc, EMUL_DOLOCK); + em->robust_futexes = args->head; + EMUL_UNLOCK(&emul_lock); + + return (0); +} + +int +linux_get_robust_list(struct thread *td, struct linux_get_robust_list_args *args) +{ + struct linux_emuldata *em; + struct linux_robust_list_head *head; + l_size_t len = sizeof(struct linux_robust_list_head); + int error = 0; + +#ifdef DEBUG + if (ldebug(get_robust_list)) + printf(ARGS(get_robust_list, "")); +#endif + + if (!args->pid) { + em = em_find(td->td_proc, EMUL_DONTLOCK); + head = em->robust_futexes; + } else { + struct proc *p; + + p = pfind(args->pid); + if (p == NULL) + return (ESRCH); + + em = em_find(p, EMUL_DONTLOCK); + /* XXX: ptrace? */ + if (priv_check(td, PRIV_CRED_SETUID) || + priv_check(td, PRIV_CRED_SETEUID) || + p_candebug(td, p)) + return (EPERM); + head = em->robust_futexes; + + PROC_UNLOCK(p); + } + + error = copyout(&len, args->len, sizeof(l_size_t)); + if (error) + return (EFAULT); + + error = copyout(head, args->head, sizeof(struct linux_robust_list_head)); + + return (error); +} + +static int +handle_futex_death(void *uaddr, pid_t pid, int pi) +{ + int uval, nval, mval; + struct futex *f; + +retry: + if (copyin(uaddr, &uval, 4)) + return (EFAULT); + + if ((uval & FUTEX_TID_MASK) == pid) { + mval = (uval & FUTEX_WAITERS) | FUTEX_OWNER_DIED; + nval = casuword32(uaddr, uval, mval); + + if (nval == -1) + return (EFAULT); + + if (nval != uval) + goto retry; + + if (!pi && (uval & FUTEX_WAITERS)) { + f = futex_get(uaddr, FUTEX_UNLOCKED); + futex_wake(f, 1, NULL, 0); + } + } + + return (0); +} + +static int +fetch_robust_entry(struct linux_robust_list **entry, + struct linux_robust_list **head, int *pi) +{ + l_ulong uentry; + + if (copyin((const void *)head, &uentry, sizeof(l_ulong))) + return (EFAULT); + + *entry = (void *)(uentry & ~1UL); + *pi = uentry & 1; + + return (0); +} + +/* This walks the list of robust futexes releasing them. */ +void +release_futexes(struct proc *p) +{ + struct linux_robust_list_head *head = NULL; + struct linux_robust_list *entry, *next_entry, *pending; + unsigned int limit = 2048, pi, next_pi, pip; + struct linux_emuldata *em; + l_ulong futex_offset; + int rc; + + em = em_find(p, EMUL_DONTLOCK); + head = em->robust_futexes; + + if (head == NULL) + return; + + if (fetch_robust_entry(&entry, &head->list.next, &pi)) + return; + + if (copyin(&head->futex_offset, &futex_offset, sizeof(l_ulong))) + return; + + if (fetch_robust_entry(&pending, &head->pending_list, &pip)) + return; + + while (entry != &head->list) { + rc = fetch_robust_entry(&next_entry, &entry->next, &next_pi); + + if (entry != pending) + if (handle_futex_death((char *)entry + futex_offset, + p->p_pid, pi)) + return; + + if (rc) + return; + + entry = next_entry; + pi = next_pi; + + if (!--limit) + break; + + sched_relinquish(curthread); + } + + if (pending) + handle_futex_death((char *) pending + futex_offset, + p->p_pid, pip); +} |
