kernel: Introduce SYS_inject syscall

The SYS_inject syscall will allow the user to inject Kernel Runtime Quantums
(KRQs) into the running kernel. As of now, set paths are not supported and the
initial implementation includes a NULL path used to load all deferrable drivers.

Previously during kernel startup, all deferrable drivers were loaded
automatically. This commit makes it so that they are only loaded when
sys_inject() is called with a NULL path.

Signed-off-by: Ian Moffett <ian@osmora.org>

1 files changed, 61 insertions, 0 deletions

diff --git a/sys/kern/kern_krq.c b/sys/kern/kern_krq.c
new file mode 100644
index 0000000..c12a98c
--- /dev/null
+++ b/sys/kern/kern_krq.c
@@ -0,0 +1,61 @@
+/*
+ * Copyright (c) 2023-2025 Ian Marco Moffett and the Osmora Team.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of Hyra nor the names of its
+ *    contributors may be used to endorse or promote products derived from
+ *    this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <sys/syscall.h>
+#include <sys/krq.h>
+#include <sys/errno.h>
+#include <sys/spinlock.h>
+#include <sys/driver.h>
+#include <sys/syslog.h>
+
+static struct spinlock krq_lock = {0};
+
+/*
+ * Load a kernel runtime quantum (KRQ)
+ *
+ * @arg0: path
+ *
+ * XXX: If the 'path' argument is NULL, all deferrable
+ *      drivers are loaded.
+ *
+ * TODO: Handle non-null paths where a completly seperate
+ *       module/krq can be loaded.
+ */
+scret_t
+sys_inject(struct syscall_args *scargs)
+{
+    if (scargs->arg0 != 0) {
+        return -EINVAL;
+    }
+
+    spinlock_acquire(&krq_lock);
+    DRIVERS_SCHED();
+    spinlock_release(&krq_lock);
+    return 0;
+}