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-rw-r--r--fs/ramfs/super.cc154
1 files changed, 154 insertions, 0 deletions
diff --git a/fs/ramfs/super.cc b/fs/ramfs/super.cc
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index 0000000..6f929f2
--- /dev/null
+++ b/fs/ramfs/super.cc
@@ -0,0 +1,154 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/* Copyright (C) 2026 Richard Qin */
+
+/*
+ * ramfs/super.cc — RamFS superblock: mount, fill_super, and init
+ */
+
+#include <lume/fs.h>
+#include <lume/dcache.h>
+#include <lume/file.h>
+#include <lume/mount.h>
+#include <lume/slab.h>
+#include <lume/kprintf.h>
+#include <lume/errno.h>
+#include <lume/fs_types.h>
+
+extern inode* ramfs_get_inode(super_block* sb, const inode* dir,
+ uint32 mode, uint32 rdev);
+
+/* Superblock allocation helper (defined in super.cc) */
+extern super_block* alloc_super(file_system_type* type);
+
+/* ================================================================== */
+/* ramfs super_operations */
+/* ================================================================== */
+
+static inode* ramfs_alloc_inode(super_block* sb)
+{
+ return new inode{};
+}
+
+static void ramfs_destroy_inode(inode* ip)
+{
+ /* Free ramfs_file_data if any */
+ if (ip->i_private) {
+ struct ramfs_file_data {
+ char* buf;
+ uint64 capacity;
+ };
+ auto* data = static_cast<ramfs_file_data*>(ip->i_private);
+ delete[] data->buf;
+ delete data;
+ }
+ delete ip;
+}
+
+static int ramfs_statfs(dentry* de, kstatfs* buf)
+{
+ /* Simple fake values */
+ buf->f_type = 0x858458f6; /* RAMFS_MAGIC */
+ buf->f_bsize = 4096;
+ buf->f_blocks = 0;
+ buf->f_bfree = 0;
+ buf->f_bavail = 0;
+ buf->f_files = 0;
+ buf->f_ffree = 0;
+ buf->f_namelen = 255;
+ buf->f_frsize = 4096;
+ buf->f_flags = 0;
+ return 0;
+}
+
+static super_operations ramfs_sops;
+
+static void ramfs_sops_init()
+{
+ ramfs_sops.alloc_inode = ramfs_alloc_inode;
+ ramfs_sops.destroy_inode = ramfs_destroy_inode;
+ ramfs_sops.free_inode = nullptr;
+ ramfs_sops.dirty_inode = nullptr;
+ ramfs_sops.write_inode = nullptr;
+ ramfs_sops.drop_inode = nullptr;
+ ramfs_sops.evict_inode = nullptr;
+ ramfs_sops.put_super = nullptr;
+ ramfs_sops.sync_fs = nullptr;
+ ramfs_sops.statfs = ramfs_statfs;
+ ramfs_sops.umount_begin = nullptr;
+}
+
+/* ================================================================== */
+/* ramfs_fill_super */
+/* ================================================================== */
+
+static int ramfs_fill_super(super_block* sb, void* data, int silent)
+{
+ sb->s_op = &ramfs_sops;
+ sb->s_magic = 0x858458f6;
+ sb->s_blocksize = 4096;
+ sb->s_blocksize_bits = 12;
+ sb->s_maxbytes = 0x7FFFFFFFFFFFFFFFLL;
+ sb->s_time_gran = 1;
+
+ /* Create root inode */
+ inode* root_ip = ramfs_get_inode(sb, nullptr, S_IFDIR | 0755, 0);
+ if (!root_ip) return -ENOMEM;
+
+ /* Create root dentry */
+ sb->s_root = d_make_root(root_ip);
+ if (!sb->s_root)
+ return -ENOMEM;
+
+ return 0;
+}
+
+/* ================================================================== */
+/* ramfs_mount */
+/* ================================================================== */
+
+static super_block* ramfs_mount(file_system_type* type, int flags,
+ const char* dev_name, void* data)
+{
+ super_block* sb = alloc_super(type);
+ if (!sb) return nullptr;
+
+ int err = ramfs_fill_super(sb, data, flags & SB_SILENT);
+ if (err) {
+ delete sb;
+ return nullptr;
+ }
+
+ return sb;
+}
+
+static void ramfs_kill_sb(super_block* sb)
+{
+ /* Phase 1: no cleanup needed for ramfs */
+ (void)sb;
+}
+
+/* ================================================================== */
+/* Filesystem type registration */
+/* ================================================================== */
+
+static file_system_type ramfs_fs_type;
+
+extern void ramfs_file_ops_init();
+extern void ramfs_dir_inode_ops_init();
+
+void ramfs_init()
+{
+ /* Runtime init to avoid un-relocated absolute pointers in .data */
+ ramfs_sops_init();
+ ramfs_file_ops_init();
+ ramfs_dir_inode_ops_init();
+
+ ramfs_fs_type.name = "ramfs";
+ ramfs_fs_type.fs_flags = FS_NO_DEVICE;
+ ramfs_fs_type.mount = ramfs_mount;
+ ramfs_fs_type.kill_sb = ramfs_kill_sb;
+ list_init(&ramfs_fs_type.fs_list);
+
+ register_filesystem(&ramfs_fs_type);
+}
+