From 2c78dc983d09e136dd016ae6ecee6b191e033de1 Mon Sep 17 00:00:00 2001
From: dzwdz
Date: Mon, 25 Sep 2023 00:12:57 +0200
Subject: kernel/intr: accept a message, allow killing processes via intrs

---
 src/kernel/proc.c       |  9 ++++++++-
 src/kernel/proc.h       |  2 +-
 src/kernel/syscalls.c   | 16 +++++++++++++---
 src/kernel/vfs/procfs.c |  4 +++-
 4 files changed, 25 insertions(+), 6 deletions(-)

(limited to 'src/kernel')

diff --git a/src/kernel/proc.c b/src/kernel/proc.c
index 0ce0f50..dc17af2 100644
--- a/src/kernel/proc.c
+++ b/src/kernel/proc.c
@@ -382,7 +382,14 @@ void proc_tryintr(Proc *p) {
 	}
 }
 
-void proc_intr(Proc *p) {
+void proc_intr(Proc *p, const char *buf, size_t len) {
+	assert(buf != NULL || len == 0);
+
+	if (4 <= len && memcmp(buf, "kill", 4) == 0) {
+		proc_kill(p, EINTR);
+		return;
+	}
+
 	if (!p->intr_fn) return;
 	proc_tryintr(p);
 
diff --git a/src/kernel/proc.h b/src/kernel/proc.h
index d437b8c..2261f85 100644
--- a/src/kernel/proc.h
+++ b/src/kernel/proc.h
@@ -123,7 +123,7 @@ void proc_tryreap(Proc *dead);
 void proc_tryintr(Proc *p);
 
 /** Send an interupt to a process. */
-void proc_intr(Proc *proc);
+void proc_intr(Proc *p, const char *buf, size_t len);
 
 /** Switches execution to any running process. */
 _Noreturn void proc_switch_any(void);
diff --git a/src/kernel/syscalls.c b/src/kernel/syscalls.c
index 8ff5112..edc74bb 100644
--- a/src/kernel/syscalls.c
+++ b/src/kernel/syscalls.c
@@ -356,10 +356,20 @@ void _sys_filicide(void) {
 	}
 }
 
-void _sys_intr(void) {
+int _sys_intr(const char __user *msg, size_t len) {
+	char buf[INTR_MAX];
+	int count = 0;
+	if (INTR_MAX < len) {
+		SYSCALL_RETURN(-EINVAL);
+	}
+	if (pcpy_from(proc_cur, buf, msg, len) < len) {
+		SYSCALL_RETURN(-EFAULT);
+	}
 	for (Proc *p = proc_cur->child; p; p = proc_next(p, proc_cur)) {
-		proc_intr(p);
+		proc_intr(p, buf, len);
+		count++;
 	}
+	SYSCALL_RETURN(count);
 }
 
 void _sys_intr_set(void __user *ip) {
@@ -481,7 +491,7 @@ long _syscall(long num, long a, long b, long c, long d, long e) {
 		break; case _SYS_PIPE:	_sys_pipe((userptr_t)a, b);
 		break; case _SYS_SLEEP:	_sys_sleep(a);
 		break; case _SYS_FILICIDE:	_sys_filicide();
-		break; case _SYS_INTR:	_sys_intr();
+		break; case _SYS_INTR:	_sys_intr((userptr_t)a, b);
 		break; case _SYS_INTR_SET:	_sys_intr_set((userptr_t)a);
 		break; case _SYS_GETPID:	_sys_getpid();
 		break; case _SYS_GETPPID:	_sys_getppid();
diff --git a/src/kernel/vfs/procfs.c b/src/kernel/vfs/procfs.c
index 7ba43d8..5031840 100644
--- a/src/kernel/vfs/procfs.c
+++ b/src/kernel/vfs/procfs.c
@@ -146,7 +146,9 @@ procfs_accept(VfsReq *req)
 		);
 		vfsreq_finish_short(req, res);
 	} else if (req->type == VFSOP_WRITE && h->type == PhIntr) {
-		proc_intr(p);
+		size_t len = min(sizeof buf, req->input.len);
+		len = pcpy_from(req->caller, buf, req->input.buf, len);
+		proc_intr(p, buf, len);
 		vfsreq_finish_short(req, req->input.len);
 	} else {
 		vfsreq_finish_short(req, -ENOSYS);
-- 
cgit v1.2.3