vfs filesystem mounting

src/arch/x86_64/main.c

@@ -49,6 +49,11 @@ void kmain(){
 	alloc_init();
 	
 	vfs_init();
+	
+	printf("Mounting tmpfs in /\n");
+
+	if(vfs_mount(vfs_root(), NULL, "", "tmpfs", 0, NULL))
+		_panic("Failed to mount tmpfs", 0);
 
 	_panic("End of kmain()", 0);
 

src/fs/tmpfs.c

@@ -0,0 +1,31 @@
+#include <kernel/tmpfs.h>
+#include <kernel/vfs.h>
+#include <kernel/alloc.h>
+
+static int tmpfs_mount(dirnode_t** rootptr, vnode_t* device, int mountflags, void* fsinfo){
+	
+	fs_t* desc = alloc(sizeof(fs_t));
+	
+	if(!desc)
+		return ENOMEM;
+
+	dirnode_t* root = vfs_newdirnode(desc, NULL);
+
+	if(!root){
+		free(desc);
+		return ENOMEM;
+	}
+	
+	*rootptr = root;
+	
+	return 0;
+}
+
+static fscalls_t funcs = {
+	tmpfs_mount
+};
+
+
+fscalls_t* tmpfs_getfuncs(){
+	return &funcs;
+}

src/fs/vfs.c

@@ -5,24 +5,88 @@
 #include <string.h>
 
 dirnode_t* vfsroot;
+hashtable  fsfuncs;
 
-vnode_t* vfs_newnode(fs_t* fs, void* fsdata){
+static inline dirnode_t* mountpoint(dirnode_t* node){
+	dirnode_t* ret = node;
+	while(ret->mount)
+		ret = ret->mount;
+	return ret;
+}
+
+int vfs_mount(dirnode_t* ref, char* device, char* mountpoint, char* fs, int mountflags, void* fsinfo){
+	
+	fscalls_t* fscalls = hashtable_get(&fsfuncs, fs);
+	
+	if(!fscalls)
+		return ENODEV;
+
+	vnode_t* dev = NULL;
+	dirnode_t* mountdir = ref;
+
+	if(device){
+		dev = ref;
+		if(*device){
+			int result = vfs_resolvepath(&dev, ref, device);
+			
+			if(result)
+				return result;
+		}
+	}
+
+
+	int result = vfs_resolvepath(&mountdir, ref, mountpoint);
+	
+	if(result)
+		return result;
+	
+	if(GETTYPE(mountdir->vnode.st.st_mode) != TYPE_DIR)
+		return ENOTDIR;
+
+	dirnode_t* mount;
+	
+	result = fscalls->mount(&mount, dev, mountflags, fsinfo);
+
+	if(result)
+		return result;
+
+	mountdir->mount = mount;
+
+	return 0;
+}
+
+vnode_t* vfs_newnode(char* name, fs_t* fs, void* fsdata){
 	vnode_t* node = alloc(sizeof(vnode_t));
 	if(!node) return NULL;
+	node->name = alloc(strlen(name)+1);
+	if(!name){
+		free(node);
+		return NULL;
+	}
+
 	node->fs = fs;
 	node->fsdata = fsdata;
-	
+	strcpy(node->name, name);
+
 	return node;
 }
 
 
-dirnode_t* vfs_newdirnode(fs_t* fs, void* fsdata){
+dirnode_t* vfs_newdirnode(char* name, fs_t* fs, void* fsdata){
 	
 	dirnode_t* node = alloc(sizeof(dirnode_t));
 	if(!node) return NULL;
 	vnode_t* vnode = (vnode_t*)node;
+	
+	vnode->name = alloc(strlen(name)+1);
+
+	if(!vnode->name){
+		free(node);
+		return NULL;
+	}
 
 	if(!hashtable_init(&node->children, 10)){ // add more here later
+		free(vnode->name);
 		free(node);
 		return NULL;
 	}
@@ -30,6 +94,10 @@ dirnode_t* vfs_newdirnode(fs_t* fs, void* fsdata){
 	vnode->st.st_mode = MAKETYPE(TYPE_DIR);
 	vnode->fs = fs;
 	vnode->fsdata = fsdata;
+	strcpy(vnode->name, name);
+
+	return node;
+
 }
 
 int vfs_resolvepath(vnode_t** result, dirnode_t* ref, char *path){
@@ -38,25 +106,33 @@ int vfs_resolvepath(vnode_t** result, dirnode_t* ref, char *path){
 	char name[512];
 	off_t nameoffset = 0;
 
-	while(nameoffset <= strlen(path)){
+	memset(name, 0, 512);
+	
+	iterator = mountpoint(iterator);
+
+	while(nameoffset < strlen(path)){
 		
 		size_t offset = 0;
 
-		while(path[nameoffset])
+		while(path[nameoffset] && path[nameoffset] != '/')
 			name[offset++] = path[nameoffset++];
 
+		if(path[nameoffset] == '/')
+			++nameoffset;
+
 		name[offset] = 0;
 
 		// make sure we're a directory
 
 		if(!GETTYPE(iterator->vnode.st.st_mode) == TYPE_DIR)
 			return ENOTDIR;
-		
-		// find correct node if mountmoint
 
-		while(iterator->mountednode)
+		// get the right vnode for this point
-			iterator = iterator->mountednode;
 		
+		iterator = mountpoint(iterator);
+
+		// now try to get the right child
+
 		vnode_t* child = hashtable_get(&iterator->children, name);
 
 		if(!child){
@@ -72,7 +148,7 @@ int vfs_resolvepath(vnode_t** result, dirnode_t* ref, char *path){
 		iterator = (dirnode_t*)child;
 
 	}
-	
+
 	*result = (vnode_t*)iterator;
 
 	return 0;
@@ -93,21 +169,23 @@ dirnode_t* vfs_root(){
 }
 
 void vfs_acquirenode(vnode_t* node){
-	while(node){
+	++node->refcount;
-		++node->refcount;
-		node = (vnode_t*)node->parent;
-	}
 }
 
 void vfs_releasenode(vnode_t* node){
-	while(node){
+	--node->refcount;
-		--node->refcount;
-		node = (vnode_t*)node->parent;
-	}
 }
 
+#include <kernel/tmpfs.h>
+
 void vfs_init(){
 	printf("Creating a fake root for the VFS\n");
 	
-	vfsroot = vfs_newdirnode(NULL, NULL);
+	vfsroot = vfs_newdirnode("/", NULL, NULL);
+
+	hashtable_init(&fsfuncs, 10);
+
+	hashtable_insert(&fsfuncs, "tmpfs", (void*)tmpfs_getfuncs());
+		
+	
 }

src/include/errno.h

@@ -2,5 +2,8 @@
 #define _ERRNO_H_INCLUDE
 
 #define ENOTDIR 1
+#define ENODEV  2
+#define ENOMEM  3
+#define EINVAL  4
 
 #endif

src/include/kernel/tmpfs.h

@@ -0,0 +1,8 @@
+#ifndef _TMPFS_H_INCLUDE
+#define _TMPFS_H_INCLUDE
+
+#include <kernel/vfs.h>
+
+fscalls_t* tmpfs_getfuncs();
+
+#endif

src/include/kernel/vfs.h

@@ -18,6 +18,7 @@ typedef struct {
 
 typedef struct _vnode_t {
 	stat st;
+	char* name;
 	fs_t* fs;
 	void* fsdata;
 	size_t refcount;
@@ -28,23 +29,23 @@ typedef struct _vnode_t {
 
 typedef struct _dirnode_t{
 	vnode_t vnode;
-	struct _dirnode_t* mountednode;
+	struct _dirnode_t* mount;
 	hashtable children;
 } dirnode_t;
 
 // fs specific calls called by the vfs on filesystems
 
 typedef struct _fscalls_t {
-	// prepares the filesystem using a filesystem data pointer and returns the root node
+	// prepares the filesystem using a filesystem data pointer and device, returning the root node in rootptr
-	dirnode_t* (*mount)(void*);
+	int (*mount)(dirnode_t** rootptr, vnode_t* device, int mountflags, void* fsinfo);
 	// cleanup of the filesystem
-	int	 (*umount)();
+	int	 (*umount)(fs_t* fs);
 	//	 opens a file under a dirnode
 	//	 args: parent, name
-	int	 (*open)(dirnode_t*, char*);
+	int	 (*open)(dirnode_t* parent, char* name);
-	//	 cleans up a vfsnode
+	//	 cleans up a node
 	//	 args: the node to clean
-	int	 (*close)(vnode_t*);
+	int	 (*close)(vnode_t* node);
 	//	 creates a new directory with the right mode
 	//	 args: parent, name, mode
 	int	 (*mkdir)(dirnode_t* parent, char* name, mode_t mode);
@@ -54,7 +55,7 @@ typedef struct _fscalls_t {
 } fscalls_t;
 
 
-int vfs_mount(dirnode_t* ref, char* device, char* mountpoint, char* fs);
+int vfs_mount(dirnode_t* ref, char* device, char* mountpoint, char* fs, int mountflags, void* fsinfo);
 int vfs_umount(dirnode_t* ref, char* mountpoint);
 int vfs_open(vnode_t* buf, dirnode_t* ref, char* path, int flags, mode_t mode);
 int vfs_close(vnode_t* node);
@@ -66,8 +67,8 @@ void vfs_init();
 dirnode_t* vfs_root();
 void vfs_acquirenode(vnode_t* node);
 void vfs_releasenode(vnode_t* node);
-vnode_t* vfs_newnode(fs_t* fs, void* fsdata);
+vnode_t* vfs_newnode(char* name, fs_t* fs, void* fsdata);
-dirnode_t* vfs_newdirnode(fs_t* fs, void* fsdata);
+dirnode_t* vfs_newdirnode(char* name, fs_t* fs, void* fsdata);
 void vfs_destroynode(vnode_t* node);
 int  vfs_resolvepath(vnode_t** result, dirnode_t* ref, char* path);