This patchset adds a couple new options to kernel_clone_args for the vhost
layer which is going to work like PF_IO_WORKER but will differ enough that
we will need to add several fields to kernel_clone_args. This patch moves
us to a flags based approach for these types of users.
Signed-off-by: Mike Christie <[email protected]>
Suggested-by: Christian Brauner <[email protected]>
Acked-by: Christian Brauner <[email protected]>
Reviewed-by: Christoph Hellwig <[email protected]>
---
include/linux/sched/task.h | 4 +++-
kernel/fork.c | 4 ++--
2 files changed, 5 insertions(+), 3 deletions(-)
diff --git a/include/linux/sched/task.h b/include/linux/sched/task.h
index 505aaf9fe477..b0a9d6c75bcc 100644
--- a/include/linux/sched/task.h
+++ b/include/linux/sched/task.h
@@ -18,8 +18,11 @@ struct css_set;
/* All the bits taken by the old clone syscall. */
#define CLONE_LEGACY_FLAGS 0xffffffffULL
+#define USER_WORKER_IO BIT(0)
+
struct kernel_clone_args {
u64 flags;
+ u32 worker_flags;
int __user *pidfd;
int __user *child_tid;
int __user *parent_tid;
@@ -31,7 +34,6 @@ struct kernel_clone_args {
/* Number of elements in *set_tid */
size_t set_tid_size;
int cgroup;
- int io_thread;
int kthread;
int idle;
int (*fn)(void *);
diff --git a/kernel/fork.c b/kernel/fork.c
index 35aa89ed6cf4..f4f2c88d9a2a 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -2071,7 +2071,7 @@ static __latent_entropy struct task_struct *copy_process(
p->flags &= ~PF_KTHREAD;
if (args->kthread)
p->flags |= PF_KTHREAD;
- if (args->io_thread) {
+ if (args->worker_flags & USER_WORKER_IO) {
/*
* Mark us an IO worker, and block any signal that isn't
* fatal or STOP
@@ -2594,7 +2594,7 @@ struct task_struct *create_io_thread(int (*fn)(void *), void *arg, int node)
.exit_signal = (lower_32_bits(flags) & CSIGNAL),
.fn = fn,
.fn_arg = arg,
- .io_thread = 1,
+ .worker_flags = USER_WORKER_IO,
};
return copy_process(NULL, 0, node, &args);
--
2.25.1