Implement ipc_netsockdelete() syscall and automatic dangling socket cleanup

kernel/ipc/netsock/netsock.c

@@ -9,6 +9,7 @@
 #include "util/util.h"
 #include "sysdefs/ipcnetsock.h"
 #include "kprintf.h"
+#include "proc/proc.h"
 
 IpcNetSocks IPC_NETSOCKS;
 
@@ -71,7 +72,7 @@ void ipc_netsock_event(uint16_t ev, struct pico_socket *sock1) {
   spinlock_release(&netsock->spinlock);
 }
 
-IpcNetSock *ipc_netsockmake(uint16_t net, uint16_t proto, uint16_t port) {
+IpcNetSock *ipc_netsockmake(uint16_t net, uint16_t proto, uint16_t port, uint64_t pid) {
   IpcNetSock *netsock = dlmalloc(sizeof(*netsock));
   if (netsock == NULL) {
     return NULL;
@@ -89,6 +90,8 @@ IpcNetSock *ipc_netsockmake(uint16_t net, uint16_t proto, uint16_t port) {
   uint8_t *eventbuffer = dlmalloc(sizeof(IpcNetSockEventBuffer) * IPC_NETSOCK_EVENTBUFFER_MAX);
   rbuft_init(&netsock->eventbuffer, eventbuffer, sizeof(IpcNetSockEventBuffer), IPC_NETSOCK_EVENTBUFFER_MAX);
 
+  netsock->ownerpid = pid;
+
   uint16_t port_be = short_be(port);
   struct pico_ip4 inaddr_any = {0};
   pico_socket_bind(netsock->picosock, &inaddr_any, &port_be);
@@ -110,3 +113,58 @@ int32_t ipc_netsocklisten(IpcNetSock *netsock, size_t maxlisteners) {
   spinlock_release(&netsock->spinlock);
   return r == 0 ? E_OK : E_NETSOCKLISTEN;
 }
+
+int32_t ipc_netsockdelete_nolock(IpcNetSock *netsock) {
+  LL_REMOVE(IPC_NETSOCKS.netsocks, netsock);
+
+  spinlock_acquire(&netsock->spinlock);
+  pico_socket_del(netsock->picosock);
+  ipc_pipefree(netsock->datapipe);
+  dlfree(netsock->datapipe);
+  dlfree(netsock->eventbuffer.buffer);
+  spinlock_release(&netsock->spinlock);
+
+  dlfree(netsock);
+  return E_OK;
+}
+
+int32_t ipc_netsockdelete(IpcNetSock *netsock) {
+  spinlock_acquire(&IPC_NETSOCKS.spinlock);
+  LL_REMOVE(IPC_NETSOCKS.netsocks, netsock);
+  spinlock_release(&IPC_NETSOCKS.spinlock);
+
+  spinlock_acquire(&netsock->spinlock);
+  pico_socket_del(netsock->picosock);
+  ipc_pipefree(netsock->datapipe);
+  dlfree(netsock->datapipe);
+  dlfree(netsock->eventbuffer.buffer);
+  spinlock_release(&netsock->spinlock);
+
+  dlfree(netsock);
+  return E_OK;
+}
+
+void ipc_netsock_cleanup_dangling(void) {
+  IpcNetSock *ns, *nstmp;
+
+  spinlock_acquire(&IPC_NETSOCKS.spinlock);
+  spinlock_acquire(&PROCS.spinlock);
+
+  LL_FOREACH_SAFE(IPC_NETSOCKS.netsocks, ns, nstmp) {
+    bool foundowner = false;
+    Proc *proc, *proctmp;
+    LL_FOREACH_SAFE(PROCS.procs, proc, proctmp) {
+      if (ns->ownerpid == proc->pid) {
+        foundowner = true;
+        break;
+      }
+    }
+
+    if (!foundowner) {
+      ipc_netsockdelete_nolock(ns);
+    }
+  }
+
+  spinlock_release(&PROCS.spinlock);
+  spinlock_release(&IPC_NETSOCKS.spinlock);
+}

kernel/ipc/netsock/netsock.h

@@ -16,6 +16,7 @@ typedef struct IpcNetSock {
   IpcPipe *datapipe;
   RBufT eventbuffer;
   SpinLock spinlock;
+  uint64_t ownerpid;
 } IpcNetSock;
 
 typedef struct {
@@ -26,7 +27,9 @@ typedef struct {
 extern IpcNetSocks IPC_NETSOCKS;
 
 void ipc_netsockinit(void);
-IpcNetSock *ipc_netsockmake(uint16_t net, uint16_t proto, uint16_t port);
+IpcNetSock *ipc_netsockmake(uint16_t net, uint16_t proto, uint16_t port, uint64_t pid);
 int32_t ipc_netsocklisten(IpcNetSock *netsock, size_t maxlisteners);
+int32_t ipc_netsockdelete(IpcNetSock *netsock);
+void ipc_netsock_cleanup_dangling(void);
 
 #endif // NETSOCK_NETSOCK_H_

kernel/proc/proc.c

@@ -13,6 +13,7 @@
 #include "vfs/vfs.h"
 #include "bootinfo/bootinfo.h"
 #include "ipc/pipe/pipe.h"
+#include "ipc/netsock/netsock.h"
 #include "sysdefs/proc.h"
 #include "sysdefs/fs.h"
 #include "time/time.h"
@@ -246,6 +247,7 @@ void proc_reaper(void) {
 void proc_sched(void *cpustate) {
   hal_intr_disable();
   sched_ticks++;
+  ipc_netsock_cleanup_dangling();
   update_time();
   pico_stack_tick();
 

kernel/syscall/ipcnetsock.c

@@ -11,7 +11,7 @@ int32_t SYSCALL3(sys_ipc_netsockmake, net1, proto1, port1) {
   uint16_t proto = proto1;
   uint16_t port = port1;
 
-  IpcNetSock *netsock = ipc_netsockmake(net, proto, port);
+  IpcNetSock *netsock = ipc_netsockmake(net, proto, port, _caller_pid);
 
   if (netsock == NULL) {
     return E_NOMEMORY;
@@ -82,3 +82,23 @@ int32_t SYSCALL1(sys_ipc_netsockpollev, socknum1) {
 
   return (int32_t)ev;
 }
+
+int32_t SYSCALL1(sys_ipc_netsockdelete, socknum1) {
+  size_t socknum = socknum1;
+
+  spinlock_acquire(&IPC_NETSOCKS.spinlock);
+  size_t idx = 0;
+  IpcNetSock *ns, *nstmp;
+  LL_FOREACH_SAFE_IDX(IPC_NETSOCKS.netsocks, ns, nstmp, idx) {
+    if (idx == socknum) {
+      break;
+    }
+  }
+  spinlock_release(&IPC_NETSOCKS.spinlock);
+
+  if (ns == NULL) {
+    return E_NOENTRY;
+  }
+
+  return ipc_netsockdelete(ns);
+}

kernel/syscall/ipcnetsock.h

@@ -8,5 +8,6 @@
 int32_t SYSCALL3(sys_ipc_netsockmake, net1, proto1, port1);
 int32_t SYSCALL2(sys_ipc_netsocklisten, socknum1, maxlisteners1);
 int32_t SYSCALL1(sys_ipc_netsockpollev, socknum1);
+int32_t SYSCALL1(sys_ipc_netsockdelete, socknum1);
 
 #endif // SYSCALL_IPC_NETSOCK_H_

kernel/syscall/syscall.c

@@ -68,4 +68,5 @@ SyscallFn SYSCALL_TABLE[SYSCALLS_MAX] = {
   [SYS_IPC_NETSOCKMAKE]     = &sys_ipc_netsockmake,
   [SYS_IPC_NETSOCKLISTEN]   = &sys_ipc_netsocklisten,
   [SYS_IPC_NETSOCKPOLLEV]   = &sys_ipc_netsockpollev,
+  [SYS_IPC_NETSOCKDELETE]   = &sys_ipc_netsockdelete,
 };