RDMA/core: Simplify destruction of FD uobjects

FD uobjects have a weird split between the struct file and uobject
world. Simplify this to make them pure uobjects and use a generic release
method for all struct file operations.

This fixes the control flow so that mlx5_cmd_cleanup_async_ctx() is always
called before erasing the linked list contents to make the concurrancy
simpler to understand.

For this to work the uobject destruction must fence anything that it is
cleaning up - the design must not rely on struct file lifetime.

Only deliver_event() relies on the struct file to when adding new events
to the queue, add a is_destroyed check under lock to block it.

Link: https://lore.kernel.org/r/1578504126-9400-3-git-send-email-yishaih@mellanox.com
Signed-off-by: Yishai Hadas <yishaih@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

1 files changed, 1 insertions, 22 deletions

diff --git a/drivers/infiniband/core/uverbs_main.c b/drivers/infiniband/core/uverbs_main.c
index 8f5de4dcad97..da56fda259fd 100644
--- a/drivers/infiniband/core/uverbs_main.c
+++ b/drivers/infiniband/core/uverbs_main.c
@@ -373,32 +373,11 @@ static int ib_uverbs_async_event_close(struct inode *inode, struct file *filp)
 	return 0;
 }
 
-static int ib_uverbs_comp_event_close(struct inode *inode, struct file *filp)
-{
-	struct ib_uobject *uobj = filp->private_data;
-	struct ib_uverbs_completion_event_file *file = container_of(
-		uobj, struct ib_uverbs_completion_event_file, uobj);
-	struct ib_uverbs_event *entry, *tmp;
-
-	spin_lock_irq(&file->ev_queue.lock);
-	list_for_each_entry_safe(entry, tmp, &file->ev_queue.event_list, list) {
-		if (entry->counter)
-			list_del(&entry->obj_list);
-		kfree(entry);
-	}
-	file->ev_queue.is_closed = 1;
-	spin_unlock_irq(&file->ev_queue.lock);
-
-	uverbs_close_fd(filp);
-
-	return 0;
-}
-
 const struct file_operations uverbs_event_fops = {
 	.owner	 = THIS_MODULE,
 	.read	 = ib_uverbs_comp_event_read,
 	.poll    = ib_uverbs_comp_event_poll,
-	.release = ib_uverbs_comp_event_close,
+	.release = uverbs_uobject_fd_release,
 	.fasync  = ib_uverbs_comp_event_fasync,
 	.llseek	 = no_llseek,
 };