free_task(tsk);
}
+/*
+ * macro override instead of weak attribute alias, to workaround
+ * gcc 4.1.0 and 4.1.1 bugs with weak attribute and empty functions.
+ */
+#ifndef arch_task_cache_init
+#define arch_task_cache_init()
+#endif
+
void __init fork_init(unsigned long mempages)
{
#ifndef __HAVE_ARCH_TASK_STRUCT_ALLOCATOR
ARCH_MIN_TASKALIGN, SLAB_PANIC, NULL);
#endif
+ /* do the arch specific task caches init */
+ arch_task_cache_init();
+
/*
* The default maximum number of threads is set to a safe
* value: the thread structures can take up at most half
init_task.signal->rlim[RLIMIT_NPROC];
}
+int __attribute__((weak)) arch_dup_task_struct(struct task_struct *dst,
+ struct task_struct *src)
+{
+ *dst = *src;
+ return 0;
+}
+
static struct task_struct *dup_task_struct(struct task_struct *orig)
{
struct task_struct *tsk;
return NULL;
}
- *tsk = *orig;
+ err = arch_dup_task_struct(tsk, orig);
+ if (err)
+ goto out;
+
tsk->stack = ti;
err = prop_local_init_single(&tsk->dirties);
- if (err) {
- free_thread_info(ti);
- free_task_struct(tsk);
- return NULL;
- }
+ if (err)
+ goto out;
setup_thread_stack(tsk, orig);
#endif
tsk->splice_pipe = NULL;
return tsk;
+
+out:
+ free_thread_info(ti);
+ free_task_struct(tsk);
+ return NULL;
}
#ifdef CONFIG_MMU
if (!tmp)
goto fail_nomem;
*tmp = *mpnt;
- pol = mpol_copy(vma_policy(mpnt));
+ pol = mpol_dup(vma_policy(mpnt));
retval = PTR_ERR(pol);
if (IS_ERR(pol))
goto fail_nomem_policy;
mm->ioctx_list = NULL;
mm->free_area_cache = TASK_UNMAPPED_BASE;
mm->cached_hole_size = ~0UL;
- mm_init_cgroup(mm, p);
+ mm_init_owner(mm, p);
if (likely(!mm_alloc_pgd(mm))) {
mm->def_flags = 0;
return mm;
}
- mm_free_cgroup(mm);
free_mm(mm);
return NULL;
}
* is dropped: either by a lazy thread or by
* mmput. Free the page directory and the mm.
*/
-void fastcall __mmdrop(struct mm_struct *mm)
+void __mmdrop(struct mm_struct *mm)
{
BUG_ON(mm == &init_mm);
mm_free_pgd(mm);
- mm_free_cgroup(mm);
destroy_context(mm);
free_mm(mm);
}
if (atomic_dec_and_test(&mm->mm_users)) {
exit_aio(mm);
exit_mmap(mm);
+ set_mm_exe_file(mm, NULL);
if (!list_empty(&mm->mmlist)) {
spin_lock(&mmlist_lock);
list_del(&mm->mmlist);
* Allocate a new mm structure and copy contents from the
* mm structure of the passed in task structure.
*/
-static struct mm_struct *dup_mm(struct task_struct *tsk)
+struct mm_struct *dup_mm(struct task_struct *tsk)
{
struct mm_struct *mm, *oldmm = current->mm;
int err;
if (init_new_context(tsk, mm))
goto fail_nocontext;
+ dup_mm_exe_file(oldmm, mm);
+
err = dup_mmap(mm, oldmm);
if (err)
goto free_pt;
rwlock_init(&fs->lock);
fs->umask = old->umask;
read_lock(&old->lock);
- fs->rootmnt = mntget(old->rootmnt);
- fs->root = dget(old->root);
- fs->pwdmnt = mntget(old->pwdmnt);
- fs->pwd = dget(old->pwd);
- if (old->altroot) {
- fs->altrootmnt = mntget(old->altrootmnt);
- fs->altroot = dget(old->altroot);
+ fs->root = old->root;
+ path_get(&old->root);
+ fs->pwd = old->pwd;
+ path_get(&old->pwd);
+ if (old->altroot.dentry) {
+ fs->altroot = old->altroot;
+ path_get(&old->altroot);
} else {
- fs->altrootmnt = NULL;
- fs->altroot = NULL;
+ fs->altroot.mnt = NULL;
+ fs->altroot.dentry = NULL;
}
read_unlock(&old->lock);
}
goto out;
}
- /*
- * Note: we may be using current for both targets (See exec.c)
- * This works because we cache current->files (old) as oldf. Don't
- * break this.
- */
- tsk->files = NULL;
newf = dup_fd(oldf, &error);
if (!newf)
goto out;
return 0;
}
-/*
- * Helper to unshare the files of the current task.
- * We don't want to expose copy_files internals to
- * the exec layer of the kernel.
- */
-
-int unshare_files(void)
-{
- struct files_struct *files = current->files;
- int rc;
-
- BUG_ON(!files);
-
- /* This can race but the race causes us to copy when we don't
- need to and drop the copy */
- if(atomic_read(&files->count) == 1)
- {
- atomic_inc(&files->count);
- return 0;
- }
- rc = copy_files(0, current);
- if(rc)
- current->files = files;
- return rc;
-}
-
-EXPORT_SYMBOL(unshare_files);
-
static int copy_sighand(unsigned long clone_flags, struct task_struct *tsk)
{
struct sighand_struct *sig;
sig->group_exit_code = 0;
sig->group_exit_task = NULL;
sig->group_stop_count = 0;
- sig->curr_target = NULL;
+ sig->curr_target = tsk;
init_sigpending(&sig->shared_pending);
INIT_LIST_HEAD(&sig->posix_timers);
#endif
}
+#ifdef CONFIG_MM_OWNER
+void mm_init_owner(struct mm_struct *mm, struct task_struct *p)
+{
+ mm->owner = p;
+}
+#endif /* CONFIG_MM_OWNER */
+
/*
* This creates a new process as a copy of the old one,
* but does not actually start it yet.
p->audit_context = NULL;
cgroup_fork(p);
#ifdef CONFIG_NUMA
- p->mempolicy = mpol_copy(p->mempolicy);
+ p->mempolicy = mpol_dup(p->mempolicy);
if (IS_ERR(p->mempolicy)) {
retval = PTR_ERR(p->mempolicy);
p->mempolicy = NULL;
security_task_free(p);
bad_fork_cleanup_policy:
#ifdef CONFIG_NUMA
- mpol_free(p->mempolicy);
+ mpol_put(p->mempolicy);
bad_fork_cleanup_cgroup:
#endif
cgroup_exit(p, cgroup_callbacks_done);
if (!IS_ERR(p)) {
struct completion vfork;
- /*
- * this is enough to call pid_nr_ns here, but this if
- * improves optimisation of regular fork()
- */
- nr = (clone_flags & CLONE_NEWPID) ?
- task_pid_nr_ns(p, current->nsproxy->pid_ns) :
- task_pid_vnr(p);
+ nr = task_pid_vnr(p);
if (clone_flags & CLONE_PARENT_SETTID)
put_user(nr, parent_tidptr);
}
/*
- * Unsharing of semundo for tasks created with CLONE_SYSVSEM is not
- * supported yet
- */
-static int unshare_semundo(unsigned long unshare_flags, struct sem_undo_list **new_ulistp)
-{
- if (unshare_flags & CLONE_SYSVSEM)
- return -EINVAL;
-
- return 0;
-}
-
-/*
* unshare allows a process to 'unshare' part of the process
* context which was originally shared using clone. copy_*
* functions used by do_fork() cannot be used here directly
struct sighand_struct *new_sigh = NULL;
struct mm_struct *mm, *new_mm = NULL, *active_mm = NULL;
struct files_struct *fd, *new_fd = NULL;
- struct sem_undo_list *new_ulist = NULL;
struct nsproxy *new_nsproxy = NULL;
+ int do_sysvsem = 0;
check_unshare_flags(&unshare_flags);
CLONE_NEWNET))
goto bad_unshare_out;
+ /*
+ * CLONE_NEWIPC must also detach from the undolist: after switching
+ * to a new ipc namespace, the semaphore arrays from the old
+ * namespace are unreachable.
+ */
+ if (unshare_flags & (CLONE_NEWIPC|CLONE_SYSVSEM))
+ do_sysvsem = 1;
if ((err = unshare_thread(unshare_flags)))
goto bad_unshare_out;
if ((err = unshare_fs(unshare_flags, &new_fs)))
goto bad_unshare_cleanup_sigh;
if ((err = unshare_fd(unshare_flags, &new_fd)))
goto bad_unshare_cleanup_vm;
- if ((err = unshare_semundo(unshare_flags, &new_ulist)))
- goto bad_unshare_cleanup_fd;
if ((err = unshare_nsproxy_namespaces(unshare_flags, &new_nsproxy,
new_fs)))
- goto bad_unshare_cleanup_semundo;
+ goto bad_unshare_cleanup_fd;
- if (new_fs || new_mm || new_fd || new_ulist || new_nsproxy) {
+ if (new_fs || new_mm || new_fd || do_sysvsem || new_nsproxy) {
+ if (do_sysvsem) {
+ /*
+ * CLONE_SYSVSEM is equivalent to sys_exit().
+ */
+ exit_sem(current);
+ }
if (new_nsproxy) {
switch_task_namespaces(current, new_nsproxy);
if (new_nsproxy)
put_nsproxy(new_nsproxy);
-bad_unshare_cleanup_semundo:
bad_unshare_cleanup_fd:
if (new_fd)
put_files_struct(new_fd);
bad_unshare_out:
return err;
}
+
+/*
+ * Helper to unshare the files of the current task.
+ * We don't want to expose copy_files internals to
+ * the exec layer of the kernel.
+ */
+
+int unshare_files(struct files_struct **displaced)
+{
+ struct task_struct *task = current;
+ struct files_struct *copy = NULL;
+ int error;
+
+ error = unshare_fd(CLONE_FILES, ©);
+ if (error || !copy) {
+ *displaced = NULL;
+ return error;
+ }
+ *displaced = task->files;
+ task_lock(task);
+ task->files = copy;
+ task_unlock(task);
+ return 0;
+}
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff