Simple VFS layer

kernel/vfs/vfs.c

@@ -0,0 +1,108 @@
+#include <stdint.h>
+#include <stddef.h>
+#include "vfs.h"
+#include "kprintf.h"
+#include "spinlock/spinlock.h"
+#include "hal/hal.h"
+#include "util/util.h"
+#include "hshtb.h"
+#include "assert.h"
+#include "errors.h"
+#include "fs/kvfs/kvfs.h"
+
+VfsTable VFS_TABLE;
+
+static const char *vfs_strings[] = {
+  [VFS_FATFS] = "FAT",
+  [VFS_KVFS] = "Kvfs",
+};
+
+void vfs_init_kvfs(VfsMountPoint *mp) {
+  mp->read = &kvfs_read;
+  mp->write = &kvfs_write;
+  mp->remove = &kvfs_remove;
+  mp->check = &kvfs_check;
+}
+
+int32_t vfs_mount(char *mountpoint, int32_t fstype) {
+  VfsMountPoint *mp = NULL;
+
+  spinlock_acquire(&VFS_TABLE.spinlock);
+  HSHTB_ALLOC(&VFS_TABLE, mountpoints, mountpoint, label, mp);
+  spinlock_release(&VFS_TABLE.spinlock);
+
+  if (mp == NULL) {
+    return E_NOMEMORY;
+  }
+
+  hal_memcpy(mp->label, mountpoint, hal_strlen(mountpoint));
+  mp->fstype = fstype;
+  switch (fstype) {
+    case VFS_KVFS:
+      vfs_init_kvfs(mp);
+      break;
+    default:
+      return E_UNKNOWN_FSTYPE;
+  }
+
+  return E_OK;
+}
+
+int32_t vfs_read(char *mountpoint, const char *path, uint8_t *const buffer, size_t n) {
+  VfsMountPoint *mp = NULL;
+
+  spinlock_acquire(&VFS_TABLE.spinlock);
+  HSHTB_GET(&VFS_TABLE, mountpoints, mountpoint, label, mp);
+  spinlock_release(&VFS_TABLE.spinlock);
+
+  if (mp == NULL) {
+    return E_NOENTRY;
+  }
+
+  return mp->read(mp, path, buffer, n);
+}
+
+int32_t vfs_write(char *mountpoint, const char *path, const uint8_t *const buffer, size_t n) {
+  VfsMountPoint *mp = NULL;
+
+  spinlock_acquire(&VFS_TABLE.spinlock);
+  HSHTB_GET(&VFS_TABLE, mountpoints, mountpoint, label, mp);
+  spinlock_release(&VFS_TABLE.spinlock);
+
+  if (mp == NULL) {
+    return E_NOENTRY;
+  }
+
+  return mp->write(mp, path, buffer, n);
+}
+
+int32_t vfs_remove(char *mountpoint, const char *path) {
+  VfsMountPoint *mp = NULL;
+
+  spinlock_acquire(&VFS_TABLE.spinlock);
+  HSHTB_GET(&VFS_TABLE, mountpoints, mountpoint, label, mp);
+  spinlock_release(&VFS_TABLE.spinlock);
+
+  if (mp == NULL) {
+    return E_NOENTRY;
+  }
+
+  return mp->remove(mp, path);
+}
+
+void vfs_init(void) {
+  hal_memset(&VFS_TABLE, 0, sizeof(VFS_TABLE));
+  spinlock_init(&VFS_TABLE.spinlock);
+
+  ASSERT("vfs", vfs_mount("+tmpvars", VFS_KVFS) == E_OK, "could not create +tmpvars mount point\n");
+
+  LOG("vfs", "init done\n");
+
+  for (size_t i = 0; i < LEN(VFS_TABLE.mountpoints); i++) {
+    if (!VFS_TABLE.mountpoints[i].taken) continue;
+    VfsMountPoint *vmp = &VFS_TABLE.mountpoints[i];
+    LOG("vfs", "mount point %s: %s\n", vmp->label, vfs_strings[vmp->fstype]);
+    LOG("vfs", "check = %s\n", vmp->check() ? "OK" : "FAIL");
+  }
+}
+