Simple file IO with the ioctl syscall

kernel/syscall/ioctl.c

@@ -0,0 +1,139 @@
+#include <stdint.h>
+#include <stddef.h>
+#include "syscall.h"
+#include "sysdefs/ioctl.h"
+#include "errors.h"
+#include "path/path.h"
+#include "vfs/vfs.h"
+#include "kprintf.h"
+#include "proc/proc.h"
+#include "spinlock/spinlock.h"
+
+#define IOCTL_MP_MAX 0xff
+#define IOCTL_PATH_MAX VFS_PATH_MAX
+
+int32_t SYSCALL3(sys_ioctl, ioh1, cmd1, optsptr1) {
+  uint64_t ioh = ioh1;
+  uint64_t cmd = cmd1;
+  int32_t ret = E_BADIO;
+
+  switch (cmd) {
+    case IOCTL_OPENF: {
+      IOCtlOF *ioctlof = (IOCtlOF *)(void *)optsptr1;
+
+      if (ioctlof == NULL) {
+        ret = E_INVALIDARGUMENT;
+        goto done;
+      }
+
+      char mp[IOCTL_MP_MAX];
+      char path[IOCTL_PATH_MAX];
+
+      if (ioctlof->path == NULL) {
+        ret = E_INVALIDARGUMENT;
+        goto done;
+      }
+
+      path_parse(ioctlof->path, mp, path);
+
+      VfsObj *vobj = vfs_open(mp, path, ioctlof->flags);
+      if (vobj == NULL) {
+        ret = E_NOENTRY;
+        goto done;
+      }
+
+      spinlock_acquire(&PROCS.spinlock);
+
+      Proc *proc = PROCS.current;
+      if (proc->vobjcnt < PROC_VFSHANDLES_MAX) {
+        proc->vobjs[proc->vobjcnt++] = vobj;
+        ret = proc->vobjcnt - 1;
+      } else {
+        ret = E_NOMEMORY;
+      }
+
+      spinlock_release(&PROCS.spinlock);
+    } break;
+    case IOCTL_CLOSEF: {
+      spinlock_acquire(&PROCS.spinlock);
+      Proc *proc = PROCS.current;
+      VfsObj *vobj = proc->vobjs[ioh];
+      spinlock_release(&PROCS.spinlock);
+
+      if (vobj == NULL) {
+        ret = E_INVALIDARGUMENT;
+        goto done;
+      }
+
+      vfs_close(vobj);
+      ret = E_OK;
+    } break;
+    case IOCTL_WRITE: {
+      IOCtlWF *ioctlwf = (IOCtlWF *)(void *)optsptr1;
+
+      if (ioctlwf == NULL) {
+        ret = E_INVALIDARGUMENT;
+        goto done;
+      }
+
+      if (ioctlwf->buffer == NULL) {
+        ret = E_INVALIDARGUMENT;
+        goto done;
+      }
+
+      if (ioh >= PROC_VFSHANDLES_MAX) {
+        ret = E_INVALIDARGUMENT;
+        goto done;
+      }
+
+      spinlock_acquire(&PROCS.spinlock);
+      Proc *proc = PROCS.current;
+      VfsObj *vobj = proc->vobjs[ioh];
+      spinlock_release(&PROCS.spinlock);
+
+      if (vobj == NULL) {
+        ret = E_INVALIDARGUMENT;
+        goto done;
+      }
+
+      ret = vobj->write(vobj, ioctlwf->buffer, ioctlwf->len, ioctlwf->off);
+    } break;
+    case IOCTL_READ: {
+      IOCtlRF *ioctlrf = (IOCtlRF *)(void *)optsptr1;
+
+      if (ioctlrf == NULL) {
+        ret = E_INVALIDARGUMENT;
+        goto done;
+      }
+
+      if (ioctlrf->buffer == NULL) {
+        ret = E_INVALIDARGUMENT;
+        goto done;
+      }
+
+      if (ioh >= PROC_VFSHANDLES_MAX) {
+        ret = E_INVALIDARGUMENT;
+        goto done;
+      }
+
+      spinlock_acquire(&PROCS.spinlock);
+      Proc *proc = PROCS.current;
+      VfsObj *vobj = proc->vobjs[ioh];
+      spinlock_release(&PROCS.spinlock);
+
+      if (vobj == NULL) {
+        ret = E_INVALIDARGUMENT;
+        goto done;
+      }
+
+      ret = vobj->read(vobj, ioctlrf->buffer, ioctlrf->len, ioctlrf->off);
+    } break;
+    default: {
+      ret = E_INVALIDARGUMENT;
+      goto done;
+    } break;
+  }
+
+done:
+  return ret;
+}

kernel/syscall/ioctl.h

@@ -0,0 +1,9 @@
+#ifndef SYSCALL_IOCTL_H_
+#define SYSCALL_IOCTL_H_
+
+#include <stdint.h>
+#include "syscall.h"
+
+int32_t SYSCALL3(sys_ioctl, ioh1, cmd1, optsptr1);
+
+#endif // SYSCALL_IOCTL_H_

kernel/syscall/syscall.c

@@ -4,6 +4,7 @@
 #include "kprintf.h"
 #include "processctl.h"
 #include "sysdefs/syscall.h"
+#include "ioctl.h"
 
 int32_t SYSCALL1(sys_debugprint, string) {
   char *p = (char *)string;
@@ -14,4 +15,5 @@ int32_t SYSCALL1(sys_debugprint, string) {
 SyscallFn SYSCALL_TABLE[SYSCALLS_MAX] = {
   [SYS_DEBUGPRINT] = &sys_debugprint,
   [SYS_PROCESSCTL] = &sys_processctl,
+  [SYS_IOCTL]      = &sys_ioctl,
 };