IB/uverbs: Do not check for device disassociation during ioctl

Now that the ioctl path and uobjects are converted to use uverbs_api, it
is now safe to remove the disassociation protection from the common ioctl
code.

This completes the work to make destroy functions continue to work even
after device disassociation.

Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

diff --git a/drivers/infiniband/core/uverbs_ioctl.c b/drivers/infiniband/core/uverbs_ioctl.c
index 3ca700f..1a6b229 100644 (file)
--- a/drivers/infiniband/core/uverbs_ioctl.c
+++ b/drivers/infiniband/core/uverbs_ioctl.c
@@ -470,47 +470,32 @@ static int ib_uverbs_cmd_verbs(struct ib_uverbs_file *ufile,
        return ret;
 }
 
-#define IB_UVERBS_MAX_CMD_SZ 4096
-
 long ib_uverbs_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
 {
        struct ib_uverbs_file *file = filp->private_data;
        struct ib_uverbs_ioctl_hdr __user *user_hdr =
                (struct ib_uverbs_ioctl_hdr __user *)arg;
        struct ib_uverbs_ioctl_hdr hdr;
-       struct ib_device *ib_dev;
        int srcu_key;
-       long err;
+       int err;
 
-       srcu_key = srcu_read_lock(&file->device->disassociate_srcu);
-       ib_dev = srcu_dereference(file->device->ib_dev,
-                                 &file->device->disassociate_srcu);
-       if (!ib_dev) {
-               err = -EIO;
-               goto out;
-       }
+       if (unlikely(cmd != RDMA_VERBS_IOCTL))
+               return -ENOIOCTLCMD;
 
-       if (cmd == RDMA_VERBS_IOCTL) {
-               err = copy_from_user(&hdr, user_hdr, sizeof(hdr));
+       err = copy_from_user(&hdr, user_hdr, sizeof(hdr));
+       if (err)
+               return -EFAULT;
 
-               if (err || hdr.length > IB_UVERBS_MAX_CMD_SZ ||
-                   hdr.length != sizeof(hdr) + hdr.num_attrs * sizeof(struct ib_uverbs_attr)) {
-                       err = -EINVAL;
-                       goto out;
-               }
+       if (hdr.length > PAGE_SIZE ||
+           hdr.length != struct_size(&hdr, attrs, hdr.num_attrs))
+               return -EINVAL;
 
-               if (hdr.reserved1 || hdr.reserved2) {
-                       err = -EPROTONOSUPPORT;
-                       goto out;
-               }
+       if (hdr.reserved1 || hdr.reserved2)
+               return -EPROTONOSUPPORT;
 
-               err = ib_uverbs_cmd_verbs(file, &hdr, user_hdr->attrs);
-       } else {
-               err = -ENOIOCTLCMD;
-       }
-out:
+       srcu_key = srcu_read_lock(&file->device->disassociate_srcu);
+       err = ib_uverbs_cmd_verbs(file, &hdr, user_hdr->attrs);
        srcu_read_unlock(&file->device->disassociate_srcu, srcu_key);
-
        return err;
 }