diff options
Diffstat (limited to 'kernel/fork.c')
| -rw-r--r-- | kernel/fork.c | 85 |
1 files changed, 63 insertions, 22 deletions
diff --git a/kernel/fork.c b/kernel/fork.c index d66cd1014211..dc06afd725cb 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -96,6 +96,7 @@ #include <linux/kasan.h> #include <linux/scs.h> #include <linux/io_uring.h> +#include <linux/bpf.h> #include <asm/pgalloc.h> #include <linux/uaccess.h> @@ -379,14 +380,17 @@ static void account_kernel_stack(struct task_struct *tsk, int account) void *stack = task_stack_page(tsk); struct vm_struct *vm = task_stack_vm_area(tsk); + if (vm) { + int i; - /* All stack pages are in the same node. */ - if (vm) - mod_lruvec_page_state(vm->pages[0], NR_KERNEL_STACK_KB, - account * (THREAD_SIZE / 1024)); - else + for (i = 0; i < THREAD_SIZE / PAGE_SIZE; i++) + mod_lruvec_page_state(vm->pages[i], NR_KERNEL_STACK_KB, + account * (PAGE_SIZE / 1024)); + } else { + /* All stack pages are in the same node. */ mod_lruvec_kmem_state(stack, NR_KERNEL_STACK_KB, account * (THREAD_SIZE / 1024)); + } } static int memcg_charge_kernel_stack(struct task_struct *tsk) @@ -734,6 +738,7 @@ void __put_task_struct(struct task_struct *tsk) cgroup_free(tsk); task_numa_free(tsk, true); security_task_free(tsk); + bpf_task_storage_free(tsk); exit_creds(tsk); delayacct_tsk_free(tsk); put_signal_struct(tsk->signal); @@ -927,6 +932,7 @@ static struct task_struct *dup_task_struct(struct task_struct *orig, int node) tsk->splice_pipe = NULL; tsk->task_frag.page = NULL; tsk->wake_q.next = NULL; + tsk->pf_io_worker = NULL; account_kernel_stack(tsk, 1); @@ -994,6 +1000,13 @@ static void mm_init_owner(struct mm_struct *mm, struct task_struct *p) #endif } +static void mm_init_pasid(struct mm_struct *mm) +{ +#ifdef CONFIG_IOMMU_SUPPORT + mm->pasid = INIT_PASID; +#endif +} + static void mm_init_uprobes_state(struct mm_struct *mm) { #ifdef CONFIG_UPROBES @@ -1024,6 +1037,7 @@ static struct mm_struct *mm_init(struct mm_struct *mm, struct task_struct *p, mm_init_cpumask(mm); mm_init_aio(mm); mm_init_owner(mm, p); + mm_init_pasid(mm); RCU_INIT_POINTER(mm->exe_file, NULL); mmu_notifier_subscriptions_init(mm); init_tlb_flush_pending(mm); @@ -1131,7 +1145,7 @@ void mmput_async(struct mm_struct *mm) * invocations: in mmput() nobody alive left, in execve task is single * threaded. sys_prctl(PR_SET_MM_MAP/EXE_FILE) also needs to set the * mm->exe_file, but does so without using set_mm_exe_file() in order - * to do avoid the need for any locks. + * to avoid the need for any locks. */ void set_mm_exe_file(struct mm_struct *mm, struct file *new_exe_file) { @@ -1382,7 +1396,6 @@ fail_nomem: 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->nvcsw = tsk->nivcsw = 0; @@ -1409,21 +1422,15 @@ static int copy_mm(unsigned long clone_flags, struct task_struct *tsk) if (clone_flags & CLONE_VM) { mmget(oldmm); mm = oldmm; - goto good_mm; + } else { + mm = dup_mm(tsk, current->mm); + if (!mm) + return -ENOMEM; } - retval = -ENOMEM; - mm = dup_mm(tsk, current->mm); - if (!mm) - goto fail_nomem; - -good_mm: tsk->mm = mm; tsk->active_mm = mm; return 0; - -fail_nomem: - return retval; } static int copy_fs(unsigned long clone_flags, struct task_struct *tsk) @@ -1729,7 +1736,7 @@ static int pidfd_release(struct inode *inode, struct file *file) * /proc/<pid>/status where Pid and NSpid are always shown relative to * the pid namespace of the procfs instance. The difference becomes * obvious when sending around a pidfd between pid namespaces from a - * different branch of the tree, i.e. where no ancestoral relation is + * different branch of the tree, i.e. where no ancestral relation is * present between the pid namespaces: * - create two new pid namespaces ns1 and ns2 in the initial pid * namespace (also take care to create new mount namespaces in the @@ -1933,13 +1940,21 @@ static __latent_entropy struct task_struct *copy_process( recalc_sigpending(); spin_unlock_irq(¤t->sighand->siglock); retval = -ERESTARTNOINTR; - if (signal_pending(current)) + if (task_sigpending(current)) goto fork_out; retval = -ENOMEM; p = dup_task_struct(current, node); if (!p) goto fork_out; + if (args->io_thread) { + /* + * Mark us an IO worker, and block any signal that isn't + * fatal or STOP + */ + p->flags |= PF_IO_WORKER; + siginitsetinv(&p->blocked, sigmask(SIGKILL)|sigmask(SIGSTOP)); + } /* * This _must_ happen before we call free_task(), i.e. before we jump @@ -1993,6 +2008,7 @@ static __latent_entropy struct task_struct *copy_process( spin_lock_init(&p->alloc_lock); init_sigpending(&p->pending); + p->sigqueue_cache = NULL; p->utime = p->stime = p->gtime = 0; #ifdef CONFIG_ARCH_HAS_SCALED_CPUTIME @@ -2062,13 +2078,16 @@ static __latent_entropy struct task_struct *copy_process( p->sequential_io = 0; p->sequential_io_avg = 0; #endif +#ifdef CONFIG_BPF_SYSCALL + RCU_INIT_POINTER(p->bpf_storage, NULL); +#endif /* Perform scheduler related setup. Assign this task to a CPU. */ retval = sched_fork(clone_flags, p); if (retval) goto bad_fork_cleanup_policy; - retval = perf_event_init_task(p); + retval = perf_event_init_task(p, clone_flags); if (retval) goto bad_fork_cleanup_policy; retval = audit_alloc(p); @@ -2411,6 +2430,28 @@ struct mm_struct *copy_init_mm(void) } /* + * This is like kernel_clone(), but shaved down and tailored to just + * creating io_uring workers. It returns a created task, or an error pointer. + * The returned task is inactive, and the caller must fire it up through + * wake_up_new_task(p). All signals are blocked in the created task. + */ +struct task_struct *create_io_thread(int (*fn)(void *), void *arg, int node) +{ + unsigned long flags = CLONE_FS|CLONE_FILES|CLONE_SIGHAND|CLONE_THREAD| + CLONE_IO; + struct kernel_clone_args args = { + .flags = ((lower_32_bits(flags) | CLONE_VM | + CLONE_UNTRACED) & ~CSIGNAL), + .exit_signal = (lower_32_bits(flags) & CSIGNAL), + .stack = (unsigned long)fn, + .stack_size = (unsigned long)arg, + .io_thread = 1, + }; + + return copy_process(NULL, 0, node, &args); +} + +/* * Ok, this is the main fork-routine. * * It copies the process, and if successful kick-starts @@ -2687,8 +2728,8 @@ static bool clone3_args_valid(struct kernel_clone_args *kargs) return false; /* - * - make the CLONE_DETACHED bit reuseable for clone3 - * - make the CSIGNAL bits reuseable for clone3 + * - make the CLONE_DETACHED bit reusable for clone3 + * - make the CSIGNAL bits reusable for clone3 */ if (kargs->flags & (CLONE_DETACHED | CSIGNAL)) return false; |