vfs: Add devtmpfs + memfiles

2026-10-25 18:45:38 +01:00
parent d14f895288
commit c0767b4631
7 changed files with 300 additions and 0 deletions
@@ -0,0 +1,82 @@
+// SPDX-License-Identifier: ISC
+
+#include <zinnia/chardev.h>
+
+void chardev_init(
+    struct chardev* dev,
+    const struct chardev_ops* ops,
+    const struct vfs_file_ops* file_ops,
+    uint32_t major,
+    uint32_t minor
+) {
+    refcount_init(&dev->rc);
+    dev->ops = ops;
+    dev->file_ops = file_ops;
+    dev->dev = dev_make(major, minor);
+}
+
+void chardev_ref(struct chardev* dev) {
+    refcount_inc(&dev->rc);
+}
+
+void chardev_unref(struct chardev* dev) {
+    if (refcount_dec(&dev->rc) && dev->ops && dev->ops->destroy)
+        dev->ops->destroy(dev);
+}
+
+static errno_t chardev_node_open(struct vfs_node* node, struct vfs_file* file) {
+    struct chardev* dev = node->priv;
+    file->ops = dev->file_ops;
+    if (dev->ops && dev->ops->open)
+        return dev->ops->open(dev, file);
+    return 0;
+}
+
+static void chardev_node_destroy(struct vfs_node* node) {
+    chardev_unref(node->priv);
+}
+
+static const struct vfs_node_ops chardev_node_ops = {
+    .destroy = chardev_node_destroy,
+    .device = {
+        .open = chardev_node_open,
+    },
+};
+
+errno_t devtmpfs_add_chardev(const char* name, struct chardev* dev, mode_t mode) {
+    struct vfs_mknod_target target = {
+        .type = VNODE_CHARDEV,
+        .ops = &chardev_node_ops,
+        .priv = dev,
+        .rdev = dev->dev,
+    };
+
+    chardev_ref(dev);
+    struct vfs_path root = devtmpfs_root();
+    errno_t status = vfs_mknod(root, root, name, mode, &target, ident_kernel(), nullptr);
+    vfs_path_drop(root);
+    if (status)
+        chardev_unref(dev);
+    return status;
+}
+
+errno_t devtmpfs_mkdir(const char* name, mode_t mode) {
+    struct vfs_path root = devtmpfs_root();
+    errno_t status = vfs_mkdir(root, root, name, mode, ident_kernel());
+    vfs_path_drop(root);
+    return status;
+}
+
+errno_t devtmpfs_remove(const char* name) {
+    struct vfs_path root = devtmpfs_root();
+    errno_t status = vfs_unlink(root, root, name, ident_kernel());
+    vfs_path_drop(root);
+    return status;
+}
+
+errno_t devtmpfs_symlink(const char* name, const char* target) {
+    struct vfs_path root = devtmpfs_root();
+    errno_t status = vfs_symlink(root, root, name, target, ident_kernel());
+    vfs_path_drop(root);
+    return status;
+}