fix(kernel/vfs): 🎉 a complete rewrite of the vfs

This is the fourth time re-writing the VFS, hope this will be the last. Tried to make it as modular as possible so this won't be necessary in the future. 🙏

This change required the entire kernel code to be modified.

Drivers/include/block.h

@@ -0,0 +1,110 @@
+/*
+	This file is part of Fennix Kernel.
+
+	Fennix Kernel is free software: you can redistribute it and/or
+	modify it under the terms of the GNU General Public License as
+	published by the Free Software Foundation, either version 3 of
+	the License, or (at your option) any later version.
+
+	Fennix Kernel is distributed in the hope that it will be useful,
+	but WITHOUT ANY WARRANTY; without even the implied warranty of
+	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+	GNU General Public License for more details.
+
+	You should have received a copy of the GNU General Public License
+	along with Fennix Kernel. If not, see <https://www.gnu.org/licenses/>.
+*/
+
+#ifndef __FENNIX_API_BLOCK_H__
+#define __FENNIX_API_BLOCK_H__
+
+#include <types.h>
+
+#if __has_include(<interface/fs.h>)
+#include <interface/fs.h>
+#else
+#include <fs.h>
+#endif
+
+struct BlockDevice
+{
+	/**
+	 * @brief Base name of the device.
+	 *
+	 * This name is used to identify the device in the system. It should be unique
+	 * across all block devices. The kernel may append a number to this name to
+	 * create a unique device name (e.g., "ahci0", "ahci1").
+	 */
+	const char *Name;
+
+	/**
+	 * @brief Total size of the device in bytes.
+	 *
+	 * This value represents the total addressable storage capacity of the device.
+	 * It is used for bounds checking and partitioning.
+	 */
+	size_t Size;
+
+	/**
+	 * @brief Size of a single block in bytes.
+	 *
+	 * All read and write operations are performed in multiples of this block size.
+	 * Typical values are 512 or 4096 bytes.
+	 */
+	uint32_t BlockSize;
+
+	/**
+	 * @brief Number of blocks in the device.
+	 *
+	 * This value is calculated as Size / BlockSize. It represents the total number
+	 * of addressable blocks on the device.
+	 */
+	size_t BlockCount;
+
+	/**
+	 * @brief Pointer to the block device operations structure.
+	 *
+	 * This structure contains function pointers for various operations that can
+	 * be performed on the block device, such as read, write, and ioctl.
+	 * 
+	 * Yea, inode operations are used for block devices too.
+	 */
+	const InodeOperations *Ops;
+
+	/**
+	 * @brief Opaque pointer to driver-specific or hardware-specific data.
+	 *
+	 * This field allows the driver to associate private context or state with the
+	 * device, such as controller registers or internal buffers.
+	 */
+	void *PrivateData;
+};
+
+#ifndef __kernel__
+/**
+ * @brief Registers a block device with the kernel block subsystem.
+ *
+ * This function should be called by block device drivers after initializing
+ * a device. The kernel will take ownership of the device structure and assign
+ * it a unique device ID. The device will then be accessible for filesystem
+ * mounting and I/O operations.
+ *
+ * @param Device Pointer to a fully initialized BlockDevice structure. All required fields must be set and valid for the lifetime of the device.
+ * @return Device ID (dev_t) assigned by the kernel on success, or an error code on failure.
+ */
+dev_t RegisterBlockDevice(struct BlockDevice *Device);
+
+/**
+ * @brief Unregisters a block device from the kernel block subsystem.
+ *
+ * This function should be called by drivers when a device is being removed
+ * or is no longer available. The kernel will release any resources associated
+ * with the device and invalidate its device ID.
+ *
+ * @param DeviceID The device ID (dev_t) previously returned by RegisterBlockDevice().
+ * @return 0 on success, or an error code.
+ */
+int UnregisterBlockDevice(dev_t DeviceID);
+#endif // __kernel__
+
+#endif // __FENNIX_API_BLOCK_H__

Drivers/include/fs.h

@@ -322,10 +322,6 @@ struct InodeOperations
 	int (*Stat)(struct Inode *Node, struct kstat *Stat);
 } __attribute__((packed));
 
-#define I_FLAG_ROOT 0x1
-#define I_FLAG_MOUNTPOINT 0x2
-#define I_FLAG_CACHE_KEEP 0x4
-
 struct FileSystemInfo;
 struct SuperBlockOperations
 {
@@ -337,8 +333,8 @@ struct SuperBlockOperations
 	 *
 	 * Write all pending changes to the disk.
 	 *
-	 * @param Info Inode to synchronize. If NULL, synchronize all inodes.
-	 * @param Node Inode to synchronize.
+	 * @param Info Inode to synchronize.
+	 * @param Node Inode to synchronize. If NULL, synchronize all inodes.
 	 *
 	 * @return Zero on success, otherwise an error code.
 	 */
@@ -354,13 +350,50 @@ struct SuperBlockOperations
 	 * @return Zero on success, otherwise an error code.
 	 */
 	int (*Destroy)(struct FileSystemInfo *Info);
+
+	/**
+	 * Probe the filesystem.
+	 *
+	 * Check if the filesystem is supported by the driver.
+	 *
+	 * @param Device Device to probe.
+	 *
+	 * @return Zero on success, otherwise an error code.
+	 */
+	int (*Probe)(void *Device);
+
+	/**
+	 * Mount the filesystem.
+	 *
+	 * Mount the filesystem on the given device.
+	 *
+	 * @param FS Filesystem to mount.
+	 * @param Root Pointer to the root inode.
+	 * @param Device Device to mount.
+	 *
+	 * @return Zero on success, otherwise an error code.
+	 */
+	int (*Mount)(struct FileSystemInfo *FS, struct Inode **Root, void *Device);
+
+	/**
+	 * Unmount the filesystem.
+	 *
+	 * Unmount the filesystem from the given device.
+	 *
+	 * @param FS Filesystem to unmount.
+	 *
+	 * @return Zero on success, otherwise an error code.
+	 */
+	int (*Unmount)(struct FileSystemInfo *FS);
 } __attribute__((packed));
 
 struct FileSystemInfo
 {
 	const char *Name;
-	const char *RootName;
+
 	int Flags;
+	int Capabilities;
+
 	struct SuperBlockOperations SuperOps;
 	struct InodeOperations Ops;
 
@@ -368,6 +401,9 @@ struct FileSystemInfo
 } __attribute__((packed));
 
 #ifndef __kernel__
+dev_t RegisterMountPoint(FileSystemInfo *fsi, Inode *Root);
+int UnregisterMountPoint(dev_t Device);
+
 dev_t RegisterFileSystem(struct FileSystemInfo *Info, struct Inode *Root);
 int UnregisterFileSystem(dev_t Device);
 #endif // !__kernel__