* management can be a bitch. See 'mm/memory.c': 'copy_page_range()'
*/
-#include <linux/config.h>
#include <linux/slab.h>
#include <linux/init.h>
#include <linux/unistd.h>
#include <linux/module.h>
#include <linux/vmalloc.h>
#include <linux/completion.h>
-#include <linux/namespace.h>
+#include <linux/mnt_namespace.h>
#include <linux/personality.h>
+#include <linux/mempolicy.h>
#include <linux/sem.h>
#include <linux/file.h>
+#include <linux/key.h>
#include <linux/binfmts.h>
#include <linux/mman.h>
#include <linux/fs.h>
+#include <linux/nsproxy.h>
+#include <linux/capability.h>
+#include <linux/cpu.h>
+#include <linux/cpuset.h>
#include <linux/security.h>
+#include <linux/swap.h>
#include <linux/syscalls.h>
#include <linux/jiffies.h>
#include <linux/futex.h>
-#include <linux/ptrace.h>
+#include <linux/task_io_accounting_ops.h>
+#include <linux/rcupdate.h>
+#include <linux/tracehook.h>
#include <linux/mount.h>
#include <linux/audit.h>
+#include <linux/profile.h>
+#include <linux/rmap.h>
+#include <linux/acct.h>
+#include <linux/tsacct_kern.h>
+#include <linux/cn_proc.h>
+#include <linux/delayacct.h>
+#include <linux/taskstats_kern.h>
+#include <linux/random.h>
+#include <linux/ptrace.h>
+#include <linux/vs_context.h>
+#include <linux/vs_network.h>
+#include <linux/vs_limit.h>
+#include <linux/vs_memory.h>
+#include <linux/vserver/global.h>
#include <asm/pgtable.h>
#include <asm/pgalloc.h>
#include <asm/cacheflush.h>
#include <asm/tlbflush.h>
-/* The idle threads do not count..
- * Protected by write_lock_irq(&tasklist_lock)
+/*
+ * Protected counters by write_lock_irq(&tasklist_lock)
*/
-int nr_threads;
-
-int max_threads;
unsigned long total_forks; /* Handle normal Linux uptimes. */
+int nr_threads; /* The idle threads do not count.. */
-DEFINE_PER_CPU(unsigned long, process_counts) = 0;
+int max_threads; /* tunable limit on nr_threads */
-rwlock_t tasklist_lock __cacheline_aligned = RW_LOCK_UNLOCKED; /* outer */
+DEFINE_PER_CPU(unsigned long, process_counts) = 0;
-EXPORT_SYMBOL(tasklist_lock);
+__cacheline_aligned DEFINE_RWLOCK(tasklist_lock); /* outer */
int nr_processes(void)
{
int cpu;
int total = 0;
- for_each_cpu(cpu)
+ for_each_online_cpu(cpu)
total += per_cpu(process_counts, cpu);
return total;
#ifndef __HAVE_ARCH_TASK_STRUCT_ALLOCATOR
# define alloc_task_struct() kmem_cache_alloc(task_struct_cachep, GFP_KERNEL)
# define free_task_struct(tsk) kmem_cache_free(task_struct_cachep, (tsk))
-static kmem_cache_t *task_struct_cachep;
+static struct kmem_cache *task_struct_cachep;
#endif
-static void free_task(struct task_struct *tsk)
+/* SLAB cache for signal_struct structures (tsk->signal) */
+static struct kmem_cache *signal_cachep;
+
+/* SLAB cache for sighand_struct structures (tsk->sighand) */
+struct kmem_cache *sighand_cachep;
+
+/* SLAB cache for files_struct structures (tsk->files) */
+struct kmem_cache *files_cachep;
+
+/* SLAB cache for fs_struct structures (tsk->fs) */
+struct kmem_cache *fs_cachep;
+
+/* SLAB cache for vm_area_struct structures */
+struct kmem_cache *vm_area_cachep;
+
+/* SLAB cache for mm_struct structures (tsk->mm) */
+static struct kmem_cache *mm_cachep;
+
+void free_task(struct task_struct *tsk)
{
free_thread_info(tsk->thread_info);
+ rt_mutex_debug_task_free(tsk);
+ clr_vx_info(&tsk->vx_info);
+ clr_nx_info(&tsk->nx_info);
free_task_struct(tsk);
}
+EXPORT_SYMBOL(free_task);
void __put_task_struct(struct task_struct *tsk)
{
- WARN_ON(!(tsk->state & (TASK_DEAD | TASK_ZOMBIE)));
+ WARN_ON(!(tsk->exit_state & (EXIT_DEAD | EXIT_ZOMBIE)));
WARN_ON(atomic_read(&tsk->usage));
WARN_ON(tsk == current);
- if (unlikely(tsk->audit_context))
- audit_free(tsk);
security_task_free(tsk);
free_uid(tsk->user);
put_group_info(tsk->group_info);
- free_task(tsk);
-}
-
-void fastcall add_wait_queue(wait_queue_head_t *q, wait_queue_t * wait)
-{
- unsigned long flags;
-
- wait->flags &= ~WQ_FLAG_EXCLUSIVE;
- spin_lock_irqsave(&q->lock, flags);
- __add_wait_queue(q, wait);
- spin_unlock_irqrestore(&q->lock, flags);
-}
-
-EXPORT_SYMBOL(add_wait_queue);
-
-void fastcall add_wait_queue_exclusive(wait_queue_head_t *q, wait_queue_t * wait)
-{
- unsigned long flags;
-
- wait->flags |= WQ_FLAG_EXCLUSIVE;
- spin_lock_irqsave(&q->lock, flags);
- __add_wait_queue_tail(q, wait);
- spin_unlock_irqrestore(&q->lock, flags);
-}
-
-EXPORT_SYMBOL(add_wait_queue_exclusive);
+ delayacct_tsk_free(tsk);
-void fastcall remove_wait_queue(wait_queue_head_t *q, wait_queue_t * wait)
-{
- unsigned long flags;
-
- spin_lock_irqsave(&q->lock, flags);
- __remove_wait_queue(q, wait);
- spin_unlock_irqrestore(&q->lock, flags);
+ if (!profile_handoff_task(tsk))
+ free_task(tsk);
}
-EXPORT_SYMBOL(remove_wait_queue);
-
-
-/*
- * Note: we use "set_current_state()" _after_ the wait-queue add,
- * because we need a memory barrier there on SMP, so that any
- * wake-function that tests for the wait-queue being active
- * will be guaranteed to see waitqueue addition _or_ subsequent
- * tests in this thread will see the wakeup having taken place.
- *
- * The spin_unlock() itself is semi-permeable and only protects
- * one way (it only protects stuff inside the critical region and
- * stops them from bleeding out - it would still allow subsequent
- * loads to move into the the critical region).
- */
-void fastcall prepare_to_wait(wait_queue_head_t *q, wait_queue_t *wait, int state)
-{
- unsigned long flags;
-
- wait->flags &= ~WQ_FLAG_EXCLUSIVE;
- spin_lock_irqsave(&q->lock, flags);
- if (list_empty(&wait->task_list))
- __add_wait_queue(q, wait);
- set_current_state(state);
- spin_unlock_irqrestore(&q->lock, flags);
-}
-
-EXPORT_SYMBOL(prepare_to_wait);
-
-void fastcall
-prepare_to_wait_exclusive(wait_queue_head_t *q, wait_queue_t *wait, int state)
-{
- unsigned long flags;
-
- wait->flags |= WQ_FLAG_EXCLUSIVE;
- spin_lock_irqsave(&q->lock, flags);
- if (list_empty(&wait->task_list))
- __add_wait_queue_tail(q, wait);
- set_current_state(state);
- spin_unlock_irqrestore(&q->lock, flags);
-}
-
-EXPORT_SYMBOL(prepare_to_wait_exclusive);
-
-void fastcall finish_wait(wait_queue_head_t *q, wait_queue_t *wait)
-{
- unsigned long flags;
-
- __set_current_state(TASK_RUNNING);
- /*
- * We can check for list emptiness outside the lock
- * IFF:
- * - we use the "careful" check that verifies both
- * the next and prev pointers, so that there cannot
- * be any half-pending updates in progress on other
- * CPU's that we haven't seen yet (and that might
- * still change the stack area.
- * and
- * - all other users take the lock (ie we can only
- * have _one_ other CPU that looks at or modifies
- * the list).
- */
- if (!list_empty_careful(&wait->task_list)) {
- spin_lock_irqsave(&q->lock, flags);
- list_del_init(&wait->task_list);
- spin_unlock_irqrestore(&q->lock, flags);
- }
-}
-
-EXPORT_SYMBOL(finish_wait);
-
-int autoremove_wake_function(wait_queue_t *wait, unsigned mode, int sync)
-{
- int ret = default_wake_function(wait, mode, sync);
-
- if (ret)
- list_del_init(&wait->task_list);
- return ret;
-}
-
-EXPORT_SYMBOL(autoremove_wake_function);
-
void __init fork_init(unsigned long mempages)
{
#ifndef __HAVE_ARCH_TASK_STRUCT_ALLOCATOR
#endif
/* create a slab on which task_structs can be allocated */
task_struct_cachep =
- kmem_cache_create("task_struct",
- sizeof(struct task_struct),ARCH_MIN_TASKALIGN,
- 0, NULL, NULL);
- if (!task_struct_cachep)
- panic("fork_init(): cannot create task_struct SLAB cache");
+ kmem_cache_create("task_struct", sizeof(struct task_struct),
+ ARCH_MIN_TASKALIGN, SLAB_PANIC, NULL, NULL);
#endif
/*
* value: the thread structures can take up at most half
* of memory.
*/
- max_threads = mempages / (THREAD_SIZE/PAGE_SIZE) / 8;
+ max_threads = mempages / (8 * THREAD_SIZE / PAGE_SIZE);
+
/*
* we need to allow at least 20 threads to boot a system
*/
if(max_threads < 20)
max_threads = 20;
- init_task.rlim[RLIMIT_NPROC].rlim_cur = max_threads/2;
- init_task.rlim[RLIMIT_NPROC].rlim_max = max_threads/2;
+ init_task.signal->rlim[RLIMIT_NPROC].rlim_cur = max_threads/2;
+ init_task.signal->rlim[RLIMIT_NPROC].rlim_max = max_threads/2;
+ init_task.signal->rlim[RLIMIT_SIGPENDING] =
+ init_task.signal->rlim[RLIMIT_NPROC];
}
static struct task_struct *dup_task_struct(struct task_struct *orig)
return NULL;
}
- *ti = *orig->thread_info;
*tsk = *orig;
tsk->thread_info = ti;
- ti->task = tsk;
+ setup_thread_stack(tsk, orig);
+
+#ifdef CONFIG_CC_STACKPROTECTOR
+ tsk->stack_canary = get_random_int();
+#endif
/* One for us, one for whoever does the "release_task()" (usually parent) */
atomic_set(&tsk->usage,2);
+ atomic_set(&tsk->fs_excl, 0);
+#ifdef CONFIG_BLK_DEV_IO_TRACE
+ tsk->btrace_seq = 0;
+#endif
+ tsk->splice_pipe = NULL;
return tsk;
}
#ifdef CONFIG_MMU
-static inline int dup_mmap(struct mm_struct * mm, struct mm_struct * oldmm)
+static inline int dup_mmap(struct mm_struct *mm, struct mm_struct *oldmm)
{
- struct vm_area_struct * mpnt, *tmp, **pprev;
+ struct vm_area_struct *mpnt, *tmp, **pprev;
struct rb_node **rb_link, *rb_parent;
int retval;
- unsigned long charge = 0;
+ unsigned long charge;
+ struct mempolicy *pol;
down_write(&oldmm->mmap_sem);
- flush_cache_mm(current->mm);
+ flush_cache_dup_mm(oldmm);
+ /*
+ * Not linked in yet - no deadlock potential:
+ */
+ down_write_nested(&mm->mmap_sem, SINGLE_DEPTH_NESTING);
+
mm->locked_vm = 0;
mm->mmap = NULL;
mm->mmap_cache = NULL;
- mm->free_area_cache = TASK_UNMAPPED_BASE;
+ mm->free_area_cache = oldmm->mmap_base;
+ mm->cached_hole_size = ~0UL;
mm->map_count = 0;
- mm->rss = 0;
+ __set_mm_counter(mm, file_rss, 0);
+ __set_mm_counter(mm, anon_rss, 0);
cpus_clear(mm->cpu_vm_mask);
mm->mm_rb = RB_ROOT;
rb_link = &mm->mm_rb.rb_node;
rb_parent = NULL;
pprev = &mm->mmap;
- /*
- * Add it to the mmlist after the parent.
- * Doing it this way means that we can order the list,
- * and fork() won't mess up the ordering significantly.
- * Add it first so that swapoff can see any swap entries.
- */
- spin_lock(&mmlist_lock);
- list_add(&mm->mmlist, ¤t->mm->mmlist);
- mmlist_nr++;
- spin_unlock(&mmlist_lock);
-
- for (mpnt = current->mm->mmap ; mpnt ; mpnt = mpnt->vm_next) {
+ for (mpnt = oldmm->mmap; mpnt; mpnt = mpnt->vm_next) {
struct file *file;
- if(mpnt->vm_flags & VM_DONTCOPY)
+ if (mpnt->vm_flags & VM_DONTCOPY) {
+ long pages = vma_pages(mpnt);
+ vx_vmpages_sub(mm, pages);
+ vm_stat_account(mm, mpnt->vm_flags, mpnt->vm_file,
+ -pages);
continue;
+ }
+ charge = 0;
if (mpnt->vm_flags & VM_ACCOUNT) {
unsigned int len = (mpnt->vm_end - mpnt->vm_start) >> PAGE_SHIFT;
if (security_vm_enough_memory(len))
goto fail_nomem;
- charge += len;
+ charge = len;
}
- tmp = kmem_cache_alloc(vm_area_cachep, SLAB_KERNEL);
+ tmp = kmem_cache_alloc(vm_area_cachep, GFP_KERNEL);
if (!tmp)
goto fail_nomem;
*tmp = *mpnt;
+ pol = mpol_copy(vma_policy(mpnt));
+ retval = PTR_ERR(pol);
+ if (IS_ERR(pol))
+ goto fail_nomem_policy;
+ vma_set_policy(tmp, pol);
tmp->vm_flags &= ~VM_LOCKED;
tmp->vm_mm = mm;
tmp->vm_next = NULL;
+ anon_vma_link(tmp);
file = tmp->vm_file;
- INIT_LIST_HEAD(&tmp->shared);
if (file) {
- struct inode *inode = file->f_dentry->d_inode;
+ struct inode *inode = file->f_path.dentry->d_inode;
get_file(file);
if (tmp->vm_flags & VM_DENYWRITE)
atomic_dec(&inode->i_writecount);
/* insert tmp into the share list, just after mpnt */
- down(&file->f_mapping->i_shared_sem);
- list_add(&tmp->shared, &mpnt->shared);
- up(&file->f_mapping->i_shared_sem);
+ spin_lock(&file->f_mapping->i_mmap_lock);
+ tmp->vm_truncate_count = mpnt->vm_truncate_count;
+ flush_dcache_mmap_lock(file->f_mapping);
+ vma_prio_tree_add(tmp, mpnt);
+ flush_dcache_mmap_unlock(file->f_mapping);
+ spin_unlock(&file->f_mapping->i_mmap_lock);
}
/*
- * Link in the new vma and copy the page table entries:
- * link in first so that swapoff can see swap entries,
- * and try_to_unmap_one's find_vma find the new vma.
+ * Link in the new vma and copy the page table entries.
*/
- spin_lock(&mm->page_table_lock);
*pprev = tmp;
pprev = &tmp->vm_next;
rb_parent = &tmp->vm_rb;
mm->map_count++;
- retval = copy_page_range(mm, current->mm, tmp);
- spin_unlock(&mm->page_table_lock);
+ retval = copy_page_range(mm, oldmm, mpnt);
if (tmp->vm_ops && tmp->vm_ops->open)
tmp->vm_ops->open(tmp);
if (retval)
- goto fail;
+ goto out;
}
+#ifdef arch_dup_mmap
+ arch_dup_mmap(mm, oldmm);
+#endif
retval = 0;
-
out:
- flush_tlb_mm(current->mm);
+ up_write(&mm->mmap_sem);
+ flush_tlb_mm(oldmm);
up_write(&oldmm->mmap_sem);
return retval;
+fail_nomem_policy:
+ kmem_cache_free(vm_area_cachep, tmp);
fail_nomem:
retval = -ENOMEM;
-fail:
vm_unacct_memory(charge);
goto out;
}
+
static inline int mm_alloc_pgd(struct mm_struct * mm)
{
mm->pgd = pgd_alloc(mm);
#define mm_free_pgd(mm)
#endif /* CONFIG_MMU */
-spinlock_t mmlist_lock __cacheline_aligned_in_smp = SPIN_LOCK_UNLOCKED;
-int mmlist_nr;
+ __cacheline_aligned_in_smp DEFINE_SPINLOCK(mmlist_lock);
-#define allocate_mm() (kmem_cache_alloc(mm_cachep, SLAB_KERNEL))
+#define allocate_mm() (kmem_cache_alloc(mm_cachep, GFP_KERNEL))
#define free_mm(mm) (kmem_cache_free(mm_cachep, (mm)))
#include <linux/init_task.h>
atomic_set(&mm->mm_users, 1);
atomic_set(&mm->mm_count, 1);
init_rwsem(&mm->mmap_sem);
+ INIT_LIST_HEAD(&mm->mmlist);
mm->core_waiters = 0;
- mm->page_table_lock = SPIN_LOCK_UNLOCKED;
- mm->ioctx_list_lock = RW_LOCK_UNLOCKED;
+ mm->nr_ptes = 0;
+ __set_mm_counter(mm, file_rss, 0);
+ __set_mm_counter(mm, anon_rss, 0);
+ spin_lock_init(&mm->page_table_lock);
+ rwlock_init(&mm->ioctx_list_lock);
mm->ioctx_list = NULL;
- mm->default_kioctx = (struct kioctx)INIT_KIOCTX(mm->default_kioctx, *mm);
mm->free_area_cache = TASK_UNMAPPED_BASE;
+ mm->cached_hole_size = ~0UL;
if (likely(!mm_alloc_pgd(mm))) {
mm->def_flags = 0;
+ set_vx_info(&mm->mm_vx_info, current->vx_info);
return mm;
}
free_mm(mm);
mm = allocate_mm();
if (mm) {
memset(mm, 0, sizeof(*mm));
- return mm_init(mm);
+ mm = mm_init(mm);
}
- return NULL;
+ return mm;
}
/*
BUG_ON(mm == &init_mm);
mm_free_pgd(mm);
destroy_context(mm);
+ clr_vx_info(&mm->mm_vx_info);
free_mm(mm);
}
*/
void mmput(struct mm_struct *mm)
{
- if (atomic_dec_and_lock(&mm->mm_users, &mmlist_lock)) {
- list_del(&mm->mmlist);
- mmlist_nr--;
- spin_unlock(&mmlist_lock);
+ might_sleep();
+
+ if (atomic_dec_and_test(&mm->mm_users)) {
exit_aio(mm);
exit_mmap(mm);
+ if (!list_empty(&mm->mmlist)) {
+ spin_lock(&mmlist_lock);
+ list_del(&mm->mmlist);
+ spin_unlock(&mmlist_lock);
+ }
+ put_swap_token(mm);
mmdrop(mm);
}
}
+EXPORT_SYMBOL_GPL(mmput);
-/*
- * Checks if the use count of an mm is non-zero and if so
- * returns a reference to it after bumping up the use count.
- * If the use count is zero, it means this mm is going away,
- * so return NULL.
+/**
+ * get_task_mm - acquire a reference to the task's mm
+ *
+ * Returns %NULL if the task has no mm. Checks PF_BORROWED_MM (meaning
+ * this kernel workthread has transiently adopted a user mm with use_mm,
+ * to do its AIO) is not set and if so returns a reference to it, after
+ * bumping up the use count. User must release the mm via mmput()
+ * after use. Typically used by /proc and ptrace.
*/
-struct mm_struct *mmgrab(struct mm_struct *mm)
+struct mm_struct *get_task_mm(struct task_struct *task)
{
- spin_lock(&mmlist_lock);
- if (!atomic_read(&mm->mm_users))
- mm = NULL;
- else
- atomic_inc(&mm->mm_users);
- spin_unlock(&mmlist_lock);
+ struct mm_struct *mm;
+
+ task_lock(task);
+ mm = task->mm;
+ if (mm) {
+ if (task->flags & PF_BORROWED_MM)
+ mm = NULL;
+ else
+ atomic_inc(&mm->mm_users);
+ }
+ task_unlock(task);
return mm;
}
+EXPORT_SYMBOL_GPL(get_task_mm);
/* Please note the differences between mmput and mm_release.
* mmput is called whenever we stop holding onto a mm_struct,
tsk->vfork_done = NULL;
complete(vfork_done);
}
- if (tsk->clear_child_tid && atomic_read(&mm->mm_users) > 1) {
+
+ /*
+ * If we're exiting normally, clear a user-space tid field if
+ * requested. We leave this alone when dying by signal, to leave
+ * the value intact in a core dump, and to save the unnecessary
+ * trouble otherwise. Userland only wants this done for a sys_exit.
+ */
+ if (tsk->clear_child_tid
+ && !(tsk->flags & PF_SIGNALED)
+ && atomic_read(&mm->mm_users) > 1) {
u32 __user * tidptr = tsk->clear_child_tid;
tsk->clear_child_tid = NULL;
* not set up a proper pointer then tough luck.
*/
put_user(0, tidptr);
- sys_futex(tidptr, FUTEX_WAKE, 1, NULL, NULL);
+ sys_futex(tidptr, FUTEX_WAKE, 1, NULL, NULL, 0);
}
}
+/*
+ * 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 *mm, *oldmm = current->mm;
+ int err;
+
+ if (!oldmm)
+ return NULL;
+
+ mm = allocate_mm();
+ if (!mm)
+ goto fail_nomem;
+
+ memcpy(mm, oldmm, sizeof(*mm));
+ mm->mm_vx_info = NULL;
+
+ /* Initializing for Swap token stuff */
+ mm->token_priority = 0;
+ mm->last_interval = 0;
+
+ if (!mm_init(mm))
+ goto fail_nomem;
+
+ if (init_new_context(tsk, mm))
+ goto fail_nocontext;
+
+ err = dup_mmap(mm, oldmm);
+ if (err)
+ goto free_pt;
+
+ mm->hiwater_rss = get_mm_rss(mm);
+ mm->hiwater_vm = mm->total_vm;
+
+ return mm;
+
+free_pt:
+ mmput(mm);
+
+fail_nomem:
+ return NULL;
+
+fail_nocontext:
+ /*
+ * If init_new_context() failed, we cannot use mmput() to free the mm
+ * because it calls destroy_context()
+ */
+ clr_vx_info(&mm->mm_vx_info);
+ mm_free_pgd(mm);
+ free_mm(mm);
+ return NULL;
+}
+
static int copy_mm(unsigned long clone_flags, struct task_struct * tsk)
{
struct mm_struct * mm, *oldmm;
int retval;
tsk->min_flt = tsk->maj_flt = 0;
- tsk->cmin_flt = tsk->cmaj_flt = 0;
- tsk->nvcsw = tsk->nivcsw = tsk->cnvcsw = tsk->cnivcsw = 0;
+ tsk->nvcsw = tsk->nivcsw = 0;
tsk->mm = NULL;
tsk->active_mm = NULL;
if (clone_flags & CLONE_VM) {
atomic_inc(&oldmm->mm_users);
mm = oldmm;
- /*
- * There are cases where the PTL is held to ensure no
- * new threads start up in user mode using an mm, which
- * allows optimizing out ipis; the tlb_gather_mmu code
- * is an example.
- */
- spin_unlock_wait(&oldmm->page_table_lock);
goto good_mm;
}
retval = -ENOMEM;
- mm = allocate_mm();
+ mm = dup_mm(tsk);
if (!mm)
goto fail_nomem;
- /* Copy the current MM stuff.. */
- memcpy(mm, oldmm, sizeof(*mm));
- if (!mm_init(mm))
- goto fail_nomem;
-
- if (init_new_context(tsk,mm))
- goto fail_nocontext;
-
- retval = dup_mmap(mm, oldmm);
- if (retval)
- goto free_pt;
-
good_mm:
+ /* Initializing for Swap token stuff */
+ mm->token_priority = 0;
+ mm->last_interval = 0;
+
tsk->mm = mm;
tsk->active_mm = mm;
return 0;
-free_pt:
- mmput(mm);
fail_nomem:
return retval;
-
-fail_nocontext:
- /*
- * If init_new_context() failed, we cannot use mmput() to free the mm
- * because it calls destroy_context()
- */
- mm_free_pgd(mm);
- free_mm(mm);
- return retval;
}
static inline struct fs_struct *__copy_fs_struct(struct fs_struct *old)
/* We don't need to lock fs - think why ;-) */
if (fs) {
atomic_set(&fs->count, 1);
- fs->lock = RW_LOCK_UNLOCKED;
+ rwlock_init(&fs->lock);
fs->umask = old->umask;
read_lock(&old->lock);
fs->rootmnt = mntget(old->rootmnt);
fs->altroot = NULL;
}
read_unlock(&old->lock);
+ atomic_inc(&vs_global_fs);
}
return fs;
}
return 0;
}
-static int count_open_files(struct files_struct *files, int size)
+static int count_open_files(struct fdtable *fdt)
{
+ int size = fdt->max_fds;
int i;
/* Find the last open fd */
for (i = size/(8*sizeof(long)); i > 0; ) {
- if (files->open_fds->fds_bits[--i])
+ if (fdt->open_fds->fds_bits[--i])
break;
}
i = (i+1) * 8 * sizeof(long);
return i;
}
-static int copy_files(unsigned long clone_flags, struct task_struct * tsk)
+static struct files_struct *alloc_files(void)
{
- struct files_struct *oldf, *newf;
- struct file **old_fds, **new_fds;
- int open_files, nfds, size, i, error = 0;
+ struct files_struct *newf;
+ struct fdtable *fdt;
- /*
- * A background process may not have any files ...
- */
- oldf = current->files;
- if (!oldf)
+ newf = kmem_cache_alloc(files_cachep, GFP_KERNEL);
+ if (!newf)
goto out;
- if (clone_flags & CLONE_FILES) {
- atomic_inc(&oldf->count);
- goto out;
- }
+ atomic_set(&newf->count, 1);
- /*
- * 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;
- error = -ENOMEM;
- newf = kmem_cache_alloc(files_cachep, SLAB_KERNEL);
- if (!newf)
- goto out;
+ spin_lock_init(&newf->file_lock);
+ newf->next_fd = 0;
+ fdt = &newf->fdtab;
+ fdt->max_fds = NR_OPEN_DEFAULT;
+ fdt->close_on_exec = (fd_set *)&newf->close_on_exec_init;
+ fdt->open_fds = (fd_set *)&newf->open_fds_init;
+ fdt->fd = &newf->fd_array[0];
+ INIT_RCU_HEAD(&fdt->rcu);
+ fdt->next = NULL;
+ rcu_assign_pointer(newf->fdt, fdt);
+out:
+ return newf;
+}
- atomic_set(&newf->count, 1);
+/*
+ * Allocate a new files structure and copy contents from the
+ * passed in files structure.
+ * errorp will be valid only when the returned files_struct is NULL.
+ */
+static struct files_struct *dup_fd(struct files_struct *oldf, int *errorp)
+{
+ struct files_struct *newf;
+ struct file **old_fds, **new_fds;
+ int open_files, size, i;
+ struct fdtable *old_fdt, *new_fdt;
- newf->file_lock = SPIN_LOCK_UNLOCKED;
- newf->next_fd = 0;
- newf->max_fds = NR_OPEN_DEFAULT;
- newf->max_fdset = __FD_SETSIZE;
- newf->close_on_exec = &newf->close_on_exec_init;
- newf->open_fds = &newf->open_fds_init;
- newf->fd = &newf->fd_array[0];
-
- /* We don't yet have the oldf readlock, but even if the old
- fdset gets grown now, we'll only copy up to "size" fds */
- size = oldf->max_fdset;
- if (size > __FD_SETSIZE) {
- newf->max_fdset = 0;
- spin_lock(&newf->file_lock);
- error = expand_fdset(newf, size-1);
- spin_unlock(&newf->file_lock);
- if (error)
- goto out_release;
- }
- spin_lock(&oldf->file_lock);
+ *errorp = -ENOMEM;
+ newf = alloc_files();
+ if (!newf)
+ goto out;
- open_files = count_open_files(oldf, size);
+ spin_lock(&oldf->file_lock);
+ old_fdt = files_fdtable(oldf);
+ new_fdt = files_fdtable(newf);
+ open_files = count_open_files(old_fdt);
/*
- * Check whether we need to allocate a larger fd array.
- * Note: we're not a clone task, so the open count won't
- * change.
+ * Check whether we need to allocate a larger fd array and fd set.
+ * Note: we're not a clone task, so the open count won't change.
*/
- nfds = NR_OPEN_DEFAULT;
- if (open_files > nfds) {
+ if (open_files > new_fdt->max_fds) {
+ new_fdt->max_fds = 0;
spin_unlock(&oldf->file_lock);
- newf->max_fds = 0;
spin_lock(&newf->file_lock);
- error = expand_fd_array(newf, open_files-1);
+ *errorp = expand_files(newf, open_files-1);
spin_unlock(&newf->file_lock);
- if (error)
+ if (*errorp < 0)
goto out_release;
- nfds = newf->max_fds;
+ new_fdt = files_fdtable(newf);
+ /*
+ * Reacquire the oldf lock and a pointer to its fd table
+ * who knows it may have a new bigger fd table. We need
+ * the latest pointer.
+ */
spin_lock(&oldf->file_lock);
+ old_fdt = files_fdtable(oldf);
}
- old_fds = oldf->fd;
- new_fds = newf->fd;
+ old_fds = old_fdt->fd;
+ new_fds = new_fdt->fd;
- memcpy(newf->open_fds->fds_bits, oldf->open_fds->fds_bits, open_files/8);
- memcpy(newf->close_on_exec->fds_bits, oldf->close_on_exec->fds_bits, open_files/8);
+ memcpy(new_fdt->open_fds->fds_bits,
+ old_fdt->open_fds->fds_bits, open_files/8);
+ memcpy(new_fdt->close_on_exec->fds_bits,
+ old_fdt->close_on_exec->fds_bits, open_files/8);
for (i = open_files; i != 0; i--) {
struct file *f = *old_fds++;
- if (f)
+ if (f) {
get_file(f);
- *new_fds++ = f;
+ /* TODO: sum it first for check and performance */
+ vx_openfd_inc(open_files - i);
+ } else {
+ /*
+ * The fd may be claimed in the fd bitmap but not yet
+ * instantiated in the files array if a sibling thread
+ * is partway through open(). So make sure that this
+ * fd is available to the new process.
+ */
+ FD_CLR(open_files - i, new_fdt->open_fds);
+ }
+ rcu_assign_pointer(*new_fds++, f);
}
spin_unlock(&oldf->file_lock);
/* compute the remainder to be cleared */
- size = (newf->max_fds - open_files) * sizeof(struct file *);
+ size = (new_fdt->max_fds - open_files) * sizeof(struct file *);
/* This is long word aligned thus could use a optimized version */
memset(new_fds, 0, size);
- if (newf->max_fdset > open_files) {
- int left = (newf->max_fdset-open_files)/8;
+ if (new_fdt->max_fds > open_files) {
+ int left = (new_fdt->max_fds-open_files)/8;
int start = open_files / (8 * sizeof(unsigned long));
- memset(&newf->open_fds->fds_bits[start], 0, left);
- memset(&newf->close_on_exec->fds_bits[start], 0, left);
+ memset(&new_fdt->open_fds->fds_bits[start], 0, left);
+ memset(&new_fdt->close_on_exec->fds_bits[start], 0, left);
+ }
+
+ return newf;
+
+out_release:
+ kmem_cache_free(files_cachep, newf);
+out:
+ return NULL;
+}
+
+static int copy_files(unsigned long clone_flags, struct task_struct * tsk)
+{
+ struct files_struct *oldf, *newf;
+ int error = 0;
+
+ /*
+ * A background process may not have any files ...
+ */
+ oldf = current->files;
+ if (!oldf)
+ goto out;
+
+ if (clone_flags & CLONE_FILES) {
+ atomic_inc(&oldf->count);
+ 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;
+
tsk->files = newf;
error = 0;
out:
return error;
-
-out_release:
- free_fdset (newf->close_on_exec, newf->max_fdset);
- free_fdset (newf->open_fds, newf->max_fdset);
- kmem_cache_free(files_cachep, newf);
- goto out;
}
/*
struct files_struct *files = current->files;
int rc;
- if(!files)
- BUG();
+ BUG_ON(!files);
/* This can race but the race causes us to copy when we don't
need to and drop the copy */
return 0;
}
sig = kmem_cache_alloc(sighand_cachep, GFP_KERNEL);
- tsk->sighand = sig;
+ rcu_assign_pointer(tsk->sighand, sig);
if (!sig)
return -ENOMEM;
- spin_lock_init(&sig->siglock);
atomic_set(&sig->count, 1);
memcpy(sig->action, current->sighand->action, sizeof(sig->action));
return 0;
}
+void __cleanup_sighand(struct sighand_struct *sighand)
+{
+ if (atomic_dec_and_test(&sighand->count))
+ kmem_cache_free(sighand_cachep, sighand);
+}
+
static inline int copy_signal(unsigned long clone_flags, struct task_struct * tsk)
{
struct signal_struct *sig;
+ int ret;
if (clone_flags & CLONE_THREAD) {
atomic_inc(¤t->signal->count);
+ atomic_inc(¤t->signal->live);
return 0;
}
sig = kmem_cache_alloc(signal_cachep, GFP_KERNEL);
tsk->signal = sig;
if (!sig)
return -ENOMEM;
+
+ ret = copy_thread_group_keys(tsk);
+ if (ret < 0) {
+ kmem_cache_free(signal_cachep, sig);
+ return ret;
+ }
+
atomic_set(&sig->count, 1);
- sig->group_exit = 0;
+ atomic_set(&sig->live, 1);
+ init_waitqueue_head(&sig->wait_chldexit);
+ sig->flags = 0;
sig->group_exit_code = 0;
sig->group_exit_task = NULL;
sig->group_stop_count = 0;
init_sigpending(&sig->shared_pending);
INIT_LIST_HEAD(&sig->posix_timers);
- sig->tty = current->signal->tty;
- sig->pgrp = process_group(current);
- sig->session = current->signal->session;
+ hrtimer_init(&sig->real_timer, CLOCK_MONOTONIC, HRTIMER_REL);
+ sig->it_real_incr.tv64 = 0;
+ sig->real_timer.function = it_real_fn;
+ sig->tsk = tsk;
+
+ sig->it_virt_expires = cputime_zero;
+ sig->it_virt_incr = cputime_zero;
+ sig->it_prof_expires = cputime_zero;
+ sig->it_prof_incr = cputime_zero;
+
sig->leader = 0; /* session leadership doesn't inherit */
sig->tty_old_pgrp = 0;
+ sig->utime = sig->stime = sig->cutime = sig->cstime = cputime_zero;
+ sig->nvcsw = sig->nivcsw = sig->cnvcsw = sig->cnivcsw = 0;
+ sig->min_flt = sig->maj_flt = sig->cmin_flt = sig->cmaj_flt = 0;
+ sig->sched_time = 0;
+ INIT_LIST_HEAD(&sig->cpu_timers[0]);
+ INIT_LIST_HEAD(&sig->cpu_timers[1]);
+ INIT_LIST_HEAD(&sig->cpu_timers[2]);
+ taskstats_tgid_init(sig);
+
+ task_lock(current->group_leader);
+ memcpy(sig->rlim, current->signal->rlim, sizeof sig->rlim);
+ task_unlock(current->group_leader);
+
+ if (sig->rlim[RLIMIT_CPU].rlim_cur != RLIM_INFINITY) {
+ /*
+ * New sole thread in the process gets an expiry time
+ * of the whole CPU time limit.
+ */
+ tsk->it_prof_expires =
+ secs_to_cputime(sig->rlim[RLIMIT_CPU].rlim_cur);
+ }
+ acct_init_pacct(&sig->pacct);
+
return 0;
}
+void __cleanup_signal(struct signal_struct *sig)
+{
+ exit_thread_group_keys(sig);
+ kmem_cache_free(signal_cachep, sig);
+}
+
+static inline void cleanup_signal(struct task_struct *tsk)
+{
+ struct signal_struct *sig = tsk->signal;
+
+ atomic_dec(&sig->live);
+
+ if (atomic_dec_and_test(&sig->count))
+ __cleanup_signal(sig);
+}
+
static inline void copy_flags(unsigned long clone_flags, struct task_struct *p)
{
unsigned long new_flags = p->flags;
- new_flags &= ~PF_SUPERPRIV;
+ new_flags &= ~(PF_SUPERPRIV | PF_NOFREEZE);
new_flags |= PF_FORKNOEXEC;
- if (!(clone_flags & CLONE_PTRACE))
- p->ptrace = 0;
+ new_flags |= PF_STARTING;
p->flags = new_flags;
}
return current->pid;
}
+static inline void rt_mutex_init_task(struct task_struct *p)
+{
+ spin_lock_init(&p->pi_lock);
+#ifdef CONFIG_RT_MUTEXES
+ plist_head_init(&p->pi_waiters, &p->pi_lock);
+ p->pi_blocked_on = NULL;
+#endif
+}
+
/*
* This creates a new process as a copy of the old one,
* but does not actually start it yet.
* parts of the process environment (as per the clone
* flags). The actual kick-off is left to the caller.
*/
-struct task_struct *copy_process(unsigned long clone_flags,
- unsigned long stack_start,
- struct pt_regs *regs,
- unsigned long stack_size,
- int __user *parent_tidptr,
- int __user *child_tidptr)
+static struct task_struct *copy_process(unsigned long clone_flags,
+ unsigned long stack_start,
+ struct pt_regs *regs,
+ unsigned long stack_size,
+ int __user *parent_tidptr,
+ int __user *child_tidptr,
+ int pid)
{
int retval;
struct task_struct *p = NULL;
+ struct vx_info *vxi;
+ struct nx_info *nxi;
if ((clone_flags & (CLONE_NEWNS|CLONE_FS)) == (CLONE_NEWNS|CLONE_FS))
return ERR_PTR(-EINVAL);
if (!p)
goto fork_out;
+ rt_mutex_init_task(p);
+
+#ifdef CONFIG_TRACE_IRQFLAGS
+ DEBUG_LOCKS_WARN_ON(!p->hardirqs_enabled);
+ DEBUG_LOCKS_WARN_ON(!p->softirqs_enabled);
+#endif
+ init_vx_info(&p->vx_info, current->vx_info);
+ init_nx_info(&p->nx_info, current->nx_info);
+
+ /* check vserver memory */
+ if (p->mm && !(clone_flags & CLONE_VM)) {
+ if (vx_vmpages_avail(p->mm, p->mm->total_vm))
+ vx_pages_add(p->vx_info, RLIMIT_AS, p->mm->total_vm);
+ else
+ goto bad_fork_free;
+ }
+ if (p->mm && vx_flags(VXF_FORK_RSS, 0)) {
+ if (!vx_rss_avail(p->mm, get_mm_counter(p->mm, file_rss)))
+ goto bad_fork_cleanup_vm;
+ }
+
retval = -EAGAIN;
+ if (!vx_nproc_avail(1))
+ goto bad_fork_cleanup_vm;
+
if (atomic_read(&p->user->processes) >=
- p->rlim[RLIMIT_NPROC].rlim_cur) {
+ p->signal->rlim[RLIMIT_NPROC].rlim_cur) {
if (!capable(CAP_SYS_ADMIN) && !capable(CAP_SYS_RESOURCE) &&
p->user != &root_user)
- goto bad_fork_free;
+ goto bad_fork_cleanup_vm;
}
atomic_inc(&p->user->__count);
if (nr_threads >= max_threads)
goto bad_fork_cleanup_count;
- if (!try_module_get(p->thread_info->exec_domain->module))
+ if (!try_module_get(task_thread_info(p)->exec_domain->module))
goto bad_fork_cleanup_count;
if (p->binfmt && !try_module_get(p->binfmt->module))
goto bad_fork_cleanup_put_domain;
p->did_exec = 0;
+ delayacct_tsk_init(p); /* Must remain after dup_task_struct() */
copy_flags(clone_flags, p);
- if (clone_flags & CLONE_IDLETASK)
- p->pid = 0;
- else {
- p->pid = alloc_pidmap();
- if (p->pid == -1)
- goto bad_fork_cleanup;
- }
+ p->pid = pid;
retval = -EFAULT;
if (clone_flags & CLONE_PARENT_SETTID)
if (put_user(p->pid, parent_tidptr))
- goto bad_fork_cleanup;
-
- p->proc_dentry = NULL;
+ goto bad_fork_cleanup_delays_binfmt;
INIT_LIST_HEAD(&p->children);
INIT_LIST_HEAD(&p->sibling);
- init_waitqueue_head(&p->wait_chldexit);
p->vfork_done = NULL;
spin_lock_init(&p->alloc_lock);
- spin_lock_init(&p->proc_lock);
+ ptrace_init_task(p);
clear_tsk_thread_flag(p, TIF_SIGPENDING);
init_sigpending(&p->pending);
- p->it_real_value = p->it_virt_value = p->it_prof_value = 0;
- p->it_real_incr = p->it_virt_incr = p->it_prof_incr = 0;
- init_timer(&p->real_timer);
- p->real_timer.data = (unsigned long) p;
+ p->utime = cputime_zero;
+ p->stime = cputime_zero;
+ p->sched_time = 0;
+ p->rchar = 0; /* I/O counter: bytes read */
+ p->wchar = 0; /* I/O counter: bytes written */
+ p->syscr = 0; /* I/O counter: read syscalls */
+ p->syscw = 0; /* I/O counter: write syscalls */
+ task_io_accounting_init(p);
+ acct_clear_integrals(p);
+
+ p->it_virt_expires = cputime_zero;
+ p->it_prof_expires = cputime_zero;
+ p->it_sched_expires = 0;
+ INIT_LIST_HEAD(&p->cpu_timers[0]);
+ INIT_LIST_HEAD(&p->cpu_timers[1]);
+ INIT_LIST_HEAD(&p->cpu_timers[2]);
- p->utime = p->stime = 0;
- p->cutime = p->cstime = 0;
p->lock_depth = -1; /* -1 = no lock */
- p->start_time = get_jiffies_64();
+ do_posix_clock_monotonic_gettime(&p->start_time);
p->security = NULL;
p->io_context = NULL;
+ p->io_wait = NULL;
p->audit_context = NULL;
+ cpuset_fork(p);
+#ifdef CONFIG_NUMA
+ p->mempolicy = mpol_copy(p->mempolicy);
+ if (IS_ERR(p->mempolicy)) {
+ retval = PTR_ERR(p->mempolicy);
+ p->mempolicy = NULL;
+ goto bad_fork_cleanup_cpuset;
+ }
+ mpol_fix_fork_child_flag(p);
+#endif
+#ifdef CONFIG_TRACE_IRQFLAGS
+ p->irq_events = 0;
+#ifdef __ARCH_WANT_INTERRUPTS_ON_CTXSW
+ p->hardirqs_enabled = 1;
+#else
+ p->hardirqs_enabled = 0;
+#endif
+ p->hardirq_enable_ip = 0;
+ p->hardirq_enable_event = 0;
+ p->hardirq_disable_ip = _THIS_IP_;
+ p->hardirq_disable_event = 0;
+ p->softirqs_enabled = 1;
+ p->softirq_enable_ip = _THIS_IP_;
+ p->softirq_enable_event = 0;
+ p->softirq_disable_ip = 0;
+ p->softirq_disable_event = 0;
+ p->hardirq_context = 0;
+ p->softirq_context = 0;
+#endif
+#ifdef CONFIG_LOCKDEP
+ p->lockdep_depth = 0; /* no locks held yet */
+ p->curr_chain_key = 0;
+ p->lockdep_recursion = 0;
+#endif
+
+#ifdef CONFIG_DEBUG_MUTEXES
+ p->blocked_on = NULL; /* not blocked yet */
+#endif
+
+ p->tgid = p->pid;
+ if (clone_flags & CLONE_THREAD)
+ p->tgid = current->tgid;
- retval = -ENOMEM;
if ((retval = security_task_alloc(p)))
- goto bad_fork_cleanup;
+ goto bad_fork_cleanup_policy;
if ((retval = audit_alloc(p)))
goto bad_fork_cleanup_security;
/* copy all the process information */
goto bad_fork_cleanup_sighand;
if ((retval = copy_mm(clone_flags, p)))
goto bad_fork_cleanup_signal;
- if ((retval = copy_namespace(clone_flags, p)))
+ if ((retval = copy_keys(clone_flags, p)))
goto bad_fork_cleanup_mm;
+ if ((retval = copy_namespaces(clone_flags, p)))
+ goto bad_fork_cleanup_keys;
retval = copy_thread(0, clone_flags, stack_start, stack_size, p, regs);
if (retval)
- goto bad_fork_cleanup_namespace;
+ goto bad_fork_cleanup_namespaces;
p->set_child_tid = (clone_flags & CLONE_CHILD_SETTID) ? child_tidptr : NULL;
/*
* Clear TID on mm_release()?
*/
p->clear_child_tid = (clone_flags & CLONE_CHILD_CLEARTID) ? child_tidptr: NULL;
+ p->robust_list = NULL;
+#ifdef CONFIG_COMPAT
+ p->compat_robust_list = NULL;
+#endif
+ INIT_LIST_HEAD(&p->pi_state_list);
+ p->pi_state_cache = NULL;
+
+ /*
+ * sigaltstack should be cleared when sharing the same VM
+ */
+ if ((clone_flags & (CLONE_VM|CLONE_VFORK)) == CLONE_VM)
+ p->sas_ss_sp = p->sas_ss_size = 0;
/*
* Syscall tracing should be turned off in the child regardless
* of CLONE_PTRACE.
*/
clear_tsk_thread_flag(p, TIF_SYSCALL_TRACE);
+#ifdef TIF_SYSCALL_EMU
+ clear_tsk_thread_flag(p, TIF_SYSCALL_EMU);
+#endif
/* Our parent execution domain becomes current domain
These must match for thread signalling to apply */
-
p->parent_exec_id = p->self_exec_id;
/* ok, now we should be set up.. */
p->exit_signal = (clone_flags & CLONE_THREAD) ? -1 : (clone_flags & CSIGNAL);
p->pdeath_signal = 0;
-
- /* Perform scheduler related setup */
- sched_fork(p);
+ p->exit_state = 0;
/*
* Ok, make it visible to the rest of the system.
* We dont wake it up yet.
*/
- p->tgid = p->pid;
p->group_leader = p;
- INIT_LIST_HEAD(&p->ptrace_children);
- INIT_LIST_HEAD(&p->ptrace_list);
+ INIT_LIST_HEAD(&p->thread_group);
+
+ /* Perform scheduler related setup. Assign this task to a CPU. */
+ sched_fork(p, clone_flags);
/* Need tasklist lock for parent etc handling! */
write_lock_irq(&tasklist_lock);
+
+ /* for sys_ioprio_set(IOPRIO_WHO_PGRP) */
+ p->ioprio = current->ioprio;
+
/*
- * Check for pending SIGKILL! The new thread should not be allowed
- * to slip out of an OOM kill. (or normal SIGKILL.)
+ * The task hasn't been attached yet, so its cpus_allowed mask will
+ * not be changed, nor will its assigned CPU.
+ *
+ * The cpus_allowed mask of the parent may have changed after it was
+ * copied first time - so re-copy it here, then check the child's CPU
+ * to ensure it is on a valid CPU (and if not, just force it back to
+ * parent's CPU). This avoids alot of nasty races.
*/
- if (sigismember(¤t->pending.signal, SIGKILL)) {
- write_unlock_irq(&tasklist_lock);
- retval = -EINTR;
- goto bad_fork_cleanup_namespace;
- }
+ p->cpus_allowed = current->cpus_allowed;
+ if (unlikely(!cpu_isset(task_cpu(p), p->cpus_allowed) ||
+ !cpu_online(task_cpu(p))))
+ set_task_cpu(p, smp_processor_id());
/* CLONE_PARENT re-uses the old parent */
- if (clone_flags & CLONE_PARENT)
- p->real_parent = current->real_parent;
+ if (clone_flags & (CLONE_PARENT|CLONE_THREAD))
+ p->parent = current->parent;
else
- p->real_parent = current;
- p->parent = p->real_parent;
+ p->parent = current;
+
+ spin_lock(¤t->sighand->siglock);
+
+ /*
+ * Process group and session signals need to be delivered to just the
+ * parent before the fork or both the parent and the child after the
+ * fork. Restart if a signal comes in before we add the new process to
+ * it's process group.
+ * A fatal signal pending means that current will exit, so the new
+ * thread can't slip out of an OOM kill (or normal SIGKILL).
+ */
+ recalc_sigpending();
+ if (signal_pending(current)) {
+ spin_unlock(¤t->sighand->siglock);
+ write_unlock_irq(&tasklist_lock);
+ retval = -ERESTARTNOINTR;
+ goto bad_fork_cleanup_namespaces;
+ }
if (clone_flags & CLONE_THREAD) {
- spin_lock(¤t->sighand->siglock);
- /*
- * Important: if an exit-all has been started then
- * do not create this new thread - the whole thread
- * group is supposed to exit anyway.
- */
- if (current->signal->group_exit) {
- spin_unlock(¤t->sighand->siglock);
- write_unlock_irq(&tasklist_lock);
- retval = -EAGAIN;
- goto bad_fork_cleanup_namespace;
- }
- p->tgid = current->tgid;
p->group_leader = current->group_leader;
-
- if (current->signal->group_stop_count > 0) {
+ list_add_tail_rcu(&p->thread_group, &p->group_leader->thread_group);
+
+ if (!cputime_eq(current->signal->it_virt_expires,
+ cputime_zero) ||
+ !cputime_eq(current->signal->it_prof_expires,
+ cputime_zero) ||
+ current->signal->rlim[RLIMIT_CPU].rlim_cur != RLIM_INFINITY ||
+ !list_empty(¤t->signal->cpu_timers[0]) ||
+ !list_empty(¤t->signal->cpu_timers[1]) ||
+ !list_empty(¤t->signal->cpu_timers[2])) {
/*
- * There is an all-stop in progress for the group.
- * We ourselves will stop as soon as we check signals.
- * Make the new thread part of that group stop too.
+ * Have child wake up on its first tick to check
+ * for process CPU timers.
*/
- current->signal->group_stop_count++;
- set_tsk_thread_flag(p, TIF_SIGPENDING);
+ p->it_prof_expires = jiffies_to_cputime(1);
}
-
- spin_unlock(¤t->sighand->siglock);
}
- SET_LINKS(p);
- if (p->ptrace & PT_PTRACED)
- __ptrace_link(p, current->parent);
+ if (likely(p->pid)) {
+ add_parent(p);
+ tracehook_init_task(p);
+
+ if (thread_group_leader(p)) {
+ p->signal->tty = current->signal->tty;
+ p->signal->pgrp = process_group(current);
+ set_signal_session(p->signal, process_session(current));
+ attach_pid(p, PIDTYPE_PGID, process_group(p));
+ attach_pid(p, PIDTYPE_SID, process_session(p));
- attach_pid(p, PIDTYPE_PID, p->pid);
- if (thread_group_leader(p)) {
- attach_pid(p, PIDTYPE_TGID, p->tgid);
- attach_pid(p, PIDTYPE_PGID, process_group(p));
- attach_pid(p, PIDTYPE_SID, p->signal->session);
- if (p->pid)
+ list_add_tail_rcu(&p->tasks, &init_task.tasks);
__get_cpu_var(process_counts)++;
- } else
- link_pid(p, p->pids + PIDTYPE_TGID, &p->group_leader->pids[PIDTYPE_TGID].pid);
+ }
+ attach_pid(p, PIDTYPE_PID, p->pid);
+ nr_threads++;
+ }
- nr_threads++;
- write_unlock_irq(&tasklist_lock);
- retval = 0;
+ total_forks++;
+ spin_unlock(¤t->sighand->siglock);
-fork_out:
- if (retval)
- return ERR_PTR(retval);
+ /* p is copy of current */
+ vxi = p->vx_info;
+ if (vxi) {
+ claim_vx_info(vxi, p);
+ atomic_inc(&vxi->cvirt.nr_threads);
+ atomic_inc(&vxi->cvirt.total_forks);
+ vx_nproc_inc(p);
+ }
+ nxi = p->nx_info;
+ if (nxi)
+ claim_nx_info(nxi, p);
+ write_unlock_irq(&tasklist_lock);
+ proc_fork_connector(p);
return p;
-bad_fork_cleanup_namespace:
- exit_namespace(p);
+bad_fork_cleanup_namespaces:
+ exit_task_namespaces(p);
+bad_fork_cleanup_keys:
+ exit_keys(p);
bad_fork_cleanup_mm:
- exit_mm(p);
- if (p->active_mm)
- mmdrop(p->active_mm);
+ if (p->mm)
+ mmput(p->mm);
bad_fork_cleanup_signal:
- exit_signal(p);
+ cleanup_signal(p);
bad_fork_cleanup_sighand:
- exit_sighand(p);
+ __cleanup_sighand(p->sighand);
bad_fork_cleanup_fs:
exit_fs(p); /* blocking */
bad_fork_cleanup_files:
audit_free(p);
bad_fork_cleanup_security:
security_task_free(p);
-bad_fork_cleanup:
- if (p->pid > 0)
- free_pidmap(p->pid);
+bad_fork_cleanup_policy:
+#ifdef CONFIG_NUMA
+ mpol_free(p->mempolicy);
+bad_fork_cleanup_cpuset:
+#endif
+ cpuset_exit(p);
+bad_fork_cleanup_delays_binfmt:
+ delayacct_tsk_free(p);
if (p->binfmt)
module_put(p->binfmt->module);
bad_fork_cleanup_put_domain:
- module_put(p->thread_info->exec_domain->module);
+ module_put(task_thread_info(p)->exec_domain->module);
bad_fork_cleanup_count:
put_group_info(p->group_info);
atomic_dec(&p->user->processes);
free_uid(p->user);
+bad_fork_cleanup_vm:
+ if (p->mm && !(clone_flags & CLONE_VM))
+ vx_pages_sub(p->vx_info, RLIMIT_AS, p->mm->total_vm);
bad_fork_free:
free_task(p);
- goto fork_out;
+fork_out:
+ return ERR_PTR(retval);
}
-static inline int fork_traceflag (unsigned clone_flags)
+noinline struct pt_regs * __devinit __attribute__((weak)) idle_regs(struct pt_regs *regs)
{
- if (clone_flags & (CLONE_UNTRACED | CLONE_IDLETASK))
- return 0;
- else if (clone_flags & CLONE_VFORK) {
- if (current->ptrace & PT_TRACE_VFORK)
- return PTRACE_EVENT_VFORK;
- } else if ((clone_flags & CSIGNAL) != SIGCHLD) {
- if (current->ptrace & PT_TRACE_CLONE)
- return PTRACE_EVENT_CLONE;
- } else if (current->ptrace & PT_TRACE_FORK)
- return PTRACE_EVENT_FORK;
+ memset(regs, 0, sizeof(struct pt_regs));
+ return regs;
+}
- return 0;
+struct task_struct * __cpuinit fork_idle(int cpu)
+{
+ struct task_struct *task;
+ struct pt_regs regs;
+
+ task = copy_process(CLONE_VM, 0, idle_regs(®s), 0, NULL, NULL, 0);
+ if (!IS_ERR(task))
+ init_idle(task, cpu);
+
+ return task;
}
/*
int __user *child_tidptr)
{
struct task_struct *p;
- int trace = 0;
- long pid;
-
- if (unlikely(current->ptrace)) {
- trace = fork_traceflag (clone_flags);
- if (trace)
- clone_flags |= CLONE_PTRACE;
+ struct pid *pid = alloc_pid();
+ long nr;
+
+ if (!pid)
+ return -EAGAIN;
+
+ /* kernel threads are host only */
+ if ((clone_flags & CLONE_KTHREAD) && !vx_check(0, VS_ADMIN)) {
+ vxwprintk(1, "xid=%d tried to spawn a kernel thread.",
+ vx_current_xid());
+ free_pid(pid);
+ return -EPERM;
}
- p = copy_process(clone_flags, stack_start, regs, stack_size, parent_tidptr, child_tidptr);
+ nr = pid->nr;
+
+ p = copy_process(clone_flags, stack_start, regs, stack_size, parent_tidptr, child_tidptr, nr);
/*
* Do this prior waking up the new thread - the thread pointer
* might get invalid after that point, if the thread exits quickly.
*/
- pid = IS_ERR(p) ? PTR_ERR(p) : p->pid;
-
if (!IS_ERR(p)) {
+ /*
+ * When called from kernel_thread, don't do user tracing stuff.
+ */
+ int is_user = likely(user_mode(regs));
struct completion vfork;
if (clone_flags & CLONE_VFORK) {
init_completion(&vfork);
}
- if ((p->ptrace & PT_PTRACED) || (clone_flags & CLONE_STOPPED)) {
+ if (likely(is_user))
+ tracehook_report_clone(clone_flags, p);
+
+ p->flags &= ~PF_STARTING;
+
+ if (clone_flags & CLONE_STOPPED) {
/*
* We'll start up with an immediate SIGSTOP.
*/
sigaddset(&p->pending.signal, SIGSTOP);
set_tsk_thread_flag(p, TIF_SIGPENDING);
+ p->state = TASK_STOPPED;
}
-
- if (!(clone_flags & CLONE_STOPPED))
- wake_up_forked_process(p); /* do this last */
else
- p->state = TASK_STOPPED;
- ++total_forks;
+ wake_up_new_task(p, clone_flags);
- if (unlikely (trace)) {
- current->ptrace_message = pid;
- ptrace_notify ((trace << 8) | SIGTRAP);
- }
+ if (likely(is_user))
+ tracehook_report_clone_complete(clone_flags, nr, p);
if (clone_flags & CLONE_VFORK) {
wait_for_completion(&vfork);
- if (unlikely (current->ptrace & PT_TRACE_VFORK_DONE))
- ptrace_notify ((PTRACE_EVENT_VFORK_DONE << 8) | SIGTRAP);
- } else
- /*
- * Let the child process run first, to avoid most of the
- * COW overhead when the child exec()s afterwards.
- */
- set_need_resched();
+ if (likely(is_user))
+ tracehook_report_vfork_done(p, nr);
+ }
+ } else {
+ free_pid(pid);
+ nr = PTR_ERR(p);
}
- return pid;
+ return nr;
}
-/* SLAB cache for signal_struct structures (tsk->signal) */
-kmem_cache_t *signal_cachep;
-
-/* SLAB cache for sighand_struct structures (tsk->sighand) */
-kmem_cache_t *sighand_cachep;
-
-/* SLAB cache for files_struct structures (tsk->files) */
-kmem_cache_t *files_cachep;
-
-/* SLAB cache for fs_struct structures (tsk->fs) */
-kmem_cache_t *fs_cachep;
+#ifndef ARCH_MIN_MMSTRUCT_ALIGN
+#define ARCH_MIN_MMSTRUCT_ALIGN 0
+#endif
-/* SLAB cache for vm_area_struct structures */
-kmem_cache_t *vm_area_cachep;
+static void sighand_ctor(void *data, struct kmem_cache *cachep, unsigned long flags)
+{
+ struct sighand_struct *sighand = data;
-/* SLAB cache for mm_struct structures (tsk->mm) */
-kmem_cache_t *mm_cachep;
+ if ((flags & (SLAB_CTOR_VERIFY | SLAB_CTOR_CONSTRUCTOR)) ==
+ SLAB_CTOR_CONSTRUCTOR)
+ spin_lock_init(&sighand->siglock);
+}
void __init proc_caches_init(void)
{
sighand_cachep = kmem_cache_create("sighand_cache",
sizeof(struct sighand_struct), 0,
- SLAB_HWCACHE_ALIGN, NULL, NULL);
- if (!sighand_cachep)
- panic("Cannot create sighand SLAB cache");
-
+ SLAB_HWCACHE_ALIGN|SLAB_PANIC|SLAB_DESTROY_BY_RCU,
+ sighand_ctor, NULL);
signal_cachep = kmem_cache_create("signal_cache",
sizeof(struct signal_struct), 0,
- SLAB_HWCACHE_ALIGN, NULL, NULL);
- if (!signal_cachep)
- panic("Cannot create signal SLAB cache");
-
+ SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL, NULL);
files_cachep = kmem_cache_create("files_cache",
- sizeof(struct files_struct), 0,
- SLAB_HWCACHE_ALIGN, NULL, NULL);
- if (!files_cachep)
- panic("Cannot create files SLAB cache");
-
+ sizeof(struct files_struct), 0,
+ SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL, NULL);
fs_cachep = kmem_cache_create("fs_cache",
- sizeof(struct fs_struct), 0,
- SLAB_HWCACHE_ALIGN, NULL, NULL);
- if (!fs_cachep)
- panic("Cannot create fs_struct SLAB cache");
-
+ sizeof(struct fs_struct), 0,
+ SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL, NULL);
vm_area_cachep = kmem_cache_create("vm_area_struct",
sizeof(struct vm_area_struct), 0,
- 0, NULL, NULL);
- if(!vm_area_cachep)
- panic("vma_init: Cannot alloc vm_area_struct SLAB cache");
-
+ SLAB_PANIC, NULL, NULL);
mm_cachep = kmem_cache_create("mm_struct",
- sizeof(struct mm_struct), 0,
- SLAB_HWCACHE_ALIGN, NULL, NULL);
- if(!mm_cachep)
- panic("vma_init: Cannot alloc mm_struct SLAB cache");
+ sizeof(struct mm_struct), ARCH_MIN_MMSTRUCT_ALIGN,
+ SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL, NULL);
+}
+
+
+/*
+ * Check constraints on flags passed to the unshare system call and
+ * force unsharing of additional process context as appropriate.
+ */
+static inline void check_unshare_flags(unsigned long *flags_ptr)
+{
+ /*
+ * If unsharing a thread from a thread group, must also
+ * unshare vm.
+ */
+ if (*flags_ptr & CLONE_THREAD)
+ *flags_ptr |= CLONE_VM;
+
+ /*
+ * If unsharing vm, must also unshare signal handlers.
+ */
+ if (*flags_ptr & CLONE_VM)
+ *flags_ptr |= CLONE_SIGHAND;
+
+ /*
+ * If unsharing signal handlers and the task was created
+ * using CLONE_THREAD, then must unshare the thread
+ */
+ if ((*flags_ptr & CLONE_SIGHAND) &&
+ (atomic_read(¤t->signal->count) > 1))
+ *flags_ptr |= CLONE_THREAD;
+
+ /*
+ * If unsharing namespace, must also unshare filesystem information.
+ */
+ if (*flags_ptr & CLONE_NEWNS)
+ *flags_ptr |= CLONE_FS;
+}
+
+/*
+ * Unsharing of tasks created with CLONE_THREAD is not supported yet
+ */
+static int unshare_thread(unsigned long unshare_flags)
+{
+ if (unshare_flags & CLONE_THREAD)
+ return -EINVAL;
+
+ return 0;
+}
+
+/*
+ * Unshare the filesystem structure if it is being shared
+ */
+static int unshare_fs(unsigned long unshare_flags, struct fs_struct **new_fsp)
+{
+ struct fs_struct *fs = current->fs;
+
+ if ((unshare_flags & CLONE_FS) &&
+ (fs && atomic_read(&fs->count) > 1)) {
+ *new_fsp = __copy_fs_struct(current->fs);
+ if (!*new_fsp)
+ return -ENOMEM;
+ }
+
+ return 0;
+}
+
+/*
+ * Unshare the mnt_namespace structure if it is being shared
+ */
+static int unshare_mnt_namespace(unsigned long unshare_flags,
+ struct mnt_namespace **new_nsp, struct fs_struct *new_fs)
+{
+ struct mnt_namespace *ns = current->nsproxy->mnt_ns;
+
+ if ((unshare_flags & CLONE_NEWNS) && ns) {
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+
+ *new_nsp = dup_mnt_ns(current, new_fs ? new_fs : current->fs);
+ if (!*new_nsp)
+ return -ENOMEM;
+ }
+
+ return 0;
+}
+
+/*
+ * Unsharing of sighand is not supported yet
+ */
+static int unshare_sighand(unsigned long unshare_flags, struct sighand_struct **new_sighp)
+{
+ struct sighand_struct *sigh = current->sighand;
+
+ if ((unshare_flags & CLONE_SIGHAND) && atomic_read(&sigh->count) > 1)
+ return -EINVAL;
+ else
+ return 0;
+}
+
+/*
+ * Unshare vm if it is being shared
+ */
+static int unshare_vm(unsigned long unshare_flags, struct mm_struct **new_mmp)
+{
+ struct mm_struct *mm = current->mm;
+
+ if ((unshare_flags & CLONE_VM) &&
+ (mm && atomic_read(&mm->mm_users) > 1)) {
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+/*
+ * Unshare file descriptor table if it is being shared
+ */
+static int unshare_fd(unsigned long unshare_flags, struct files_struct **new_fdp)
+{
+ struct files_struct *fd = current->files;
+ int error = 0;
+
+ if ((unshare_flags & CLONE_FILES) &&
+ (fd && atomic_read(&fd->count) > 1)) {
+ *new_fdp = dup_fd(fd, &error);
+ if (!*new_fdp)
+ return error;
+ }
+
+ return 0;
+}
+
+/*
+ * 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;
+}
+
+#ifndef CONFIG_IPC_NS
+static inline int unshare_ipcs(unsigned long flags, struct ipc_namespace **ns)
+{
+ if (flags & CLONE_NEWIPC)
+ return -EINVAL;
+
+ return 0;
+}
+#endif
+
+/*
+ * 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
+ * because they modify an inactive task_struct that is being
+ * constructed. Here we are modifying the current, active,
+ * task_struct.
+ */
+asmlinkage long sys_unshare(unsigned long unshare_flags)
+{
+ int err = 0;
+ struct fs_struct *fs, *new_fs = NULL;
+ struct mnt_namespace *ns, *new_ns = NULL;
+ 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, *old_nsproxy = NULL;
+ struct uts_namespace *uts, *new_uts = NULL;
+ struct ipc_namespace *ipc, *new_ipc = NULL;
+
+ check_unshare_flags(&unshare_flags);
+
+ /* Return -EINVAL for all unsupported flags */
+ err = -EINVAL;
+ if (unshare_flags & ~(CLONE_THREAD|CLONE_FS|CLONE_NEWNS|CLONE_SIGHAND|
+ CLONE_VM|CLONE_FILES|CLONE_SYSVSEM|
+ CLONE_NEWUTS|CLONE_NEWIPC))
+ goto bad_unshare_out;
+
+ if ((err = unshare_thread(unshare_flags)))
+ goto bad_unshare_out;
+ if ((err = unshare_fs(unshare_flags, &new_fs)))
+ goto bad_unshare_cleanup_thread;
+ if ((err = unshare_mnt_namespace(unshare_flags, &new_ns, new_fs)))
+ goto bad_unshare_cleanup_fs;
+ if ((err = unshare_sighand(unshare_flags, &new_sigh)))
+ goto bad_unshare_cleanup_ns;
+ if ((err = unshare_vm(unshare_flags, &new_mm)))
+ 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_utsname(unshare_flags, &new_uts)))
+ goto bad_unshare_cleanup_semundo;
+ if ((err = unshare_ipcs(unshare_flags, &new_ipc)))
+ goto bad_unshare_cleanup_uts;
+
+ if (new_ns || new_uts || new_ipc) {
+ old_nsproxy = current->nsproxy;
+ new_nsproxy = dup_namespaces(old_nsproxy);
+ if (!new_nsproxy) {
+ err = -ENOMEM;
+ goto bad_unshare_cleanup_ipc;
+ }
+ }
+
+ if (new_fs || new_ns || new_mm || new_fd || new_ulist ||
+ new_uts || new_ipc) {
+
+ task_lock(current);
+
+ if (new_nsproxy) {
+ current->nsproxy = new_nsproxy;
+ new_nsproxy = old_nsproxy;
+ }
+
+ if (new_fs) {
+ fs = current->fs;
+ current->fs = new_fs;
+ new_fs = fs;
+ }
+
+ if (new_ns) {
+ ns = current->nsproxy->mnt_ns;
+ current->nsproxy->mnt_ns = new_ns;
+ new_ns = ns;
+ }
+
+ if (new_mm) {
+ mm = current->mm;
+ active_mm = current->active_mm;
+ current->mm = new_mm;
+ current->active_mm = new_mm;
+ activate_mm(active_mm, new_mm);
+ new_mm = mm;
+ }
+
+ if (new_fd) {
+ fd = current->files;
+ current->files = new_fd;
+ new_fd = fd;
+ }
+
+ if (new_uts) {
+ uts = current->nsproxy->uts_ns;
+ current->nsproxy->uts_ns = new_uts;
+ new_uts = uts;
+ }
+
+ if (new_ipc) {
+ ipc = current->nsproxy->ipc_ns;
+ current->nsproxy->ipc_ns = new_ipc;
+ new_ipc = ipc;
+ }
+
+ task_unlock(current);
+ }
+
+ if (new_nsproxy)
+ put_nsproxy(new_nsproxy);
+
+bad_unshare_cleanup_ipc:
+ if (new_ipc)
+ put_ipc_ns(new_ipc);
+
+bad_unshare_cleanup_uts:
+ if (new_uts)
+ put_uts_ns(new_uts);
+
+bad_unshare_cleanup_semundo:
+bad_unshare_cleanup_fd:
+ if (new_fd)
+ put_files_struct(new_fd);
+
+bad_unshare_cleanup_vm:
+ if (new_mm)
+ mmput(new_mm);
+
+bad_unshare_cleanup_sigh:
+ if (new_sigh)
+ if (atomic_dec_and_test(&new_sigh->count))
+ kmem_cache_free(sighand_cachep, new_sigh);
+
+bad_unshare_cleanup_ns:
+ if (new_ns)
+ put_mnt_ns(new_ns);
+
+bad_unshare_cleanup_fs:
+ if (new_fs)
+ put_fs_struct(new_fs);
+
+bad_unshare_cleanup_thread:
+bad_unshare_out:
+ return err;
}
git://git.onelab.eu / linux-2.6.git / blobdiff