Implement fs_subfs (it's simple, really) ; add placeholders for more syscalls

8 files changed, 265 insertions, 13 deletions

diff --git a/src/common/include/fs.h b/src/common/include/fs.h
index b238c03..880202b 100644
--- a/src/common/include/fs.h
+++ b/src/common/include/fs.h
@@ -24,7 +24,9 @@
 #define FM_BLOCKING	(0x200)
 #define FM_DCREATE	(0x1000)		// create file in directory
 #define FM_DMOVE	(0x2000)		// move file from directory
-#define FM_DUNLINK	(0x4000)		// delete file from directory
+#define FM_DDELETE	(0x4000)		// delete file from directory
+
+#define FM_ALL_MODES (0xFFFF)
 
 typedef struct {
 	int type;
diff --git a/src/common/include/syscallproto.h b/src/common/include/syscallproto.h
index 6f0418e..507bc2b 100644
--- a/src/common/include/syscallproto.h
+++ b/src/common/include/syscallproto.h
@@ -27,16 +27,60 @@
 #define SC_IOCTL		36		// args: fd, command, out void* data
 #define SC_GET_MODE		37		// args: fd -- get mode for open file handle
 
-#define SC_MAKE_FS		40
-#define SC_FS_ADD_SRC	41
-#define SC_RM_FS		42
+#define SC_MAKE_FS		40		// args: sc_make_fs_args_t
+#define SC_FS_ADD_SRC	41		// args: fs_name, fs_name_strlen, fd, opts, opts_strlen
+#define SC_SUBFS		42		// args: sc_subfs_args_t
+#define SC_RM_FS		43		// args: fs_name, fs_name_strlen
+// TODO : how do we enumerate filesystems ?
 
-#define SC_NEW_PROC		50
-#define SC_BIND_FS		51		// bind FS to child process
-#define SC_BIND_FD		52		// copy a file descriptor to child process
-#define SC_PROC_EXEC	53		// execute binary in process
+#define SC_NEW_PROC		50		// args: nothing ?
+#define SC_BIND_FS		51		// args: pid, new_name, new_name_strlen, fs_name, fs_name_strlen -- bind FS to child process
+#define SC_BIND_SUBFS	52		// args: sc_subfs_args_t -- subfs & bind to child process
+#define SC_BIND_FD		53		// args: pid, new_fd, local_fd -- copy a file descriptor to child process
+#define SC_PROC_EXEC	55		// args: pid, exec_name, exec_name_strlen -- execute binary in process
+#define SC_PROC_STATUS	56		// args: pid, proc_status_t*
+#define SC_PROC_KILL	57		// args: pid, proc_status_t* -- inconditionnally kill child process
+#define SC_PROC_WAIT	58		// args: pid, proc_status_t*
+#define SC_PROC_WAIT_ANY 59		// args: proc_status_t*
 
-// much more to do
+typedef struct {
+	const char* driver;
+	size_t driver_strlen;
+
+	const char* fs_name;
+	size_t fs_name_strlen;
+
+	int source_fd;
+
+	const char* opts;
+	size_t opts_strlen;
+} sc_make_fs_args_t;
+
+typedef struct {
+	const char* new_name;
+	size_t new_name_strlen;
+
+	const char* from_fs;
+	size_t from_fs_strlen;
+
+	const char* root;
+	size_t root_strlen;
+
+	int ok_modes;
+
+	int bind_to_pid;		// used only for SC_BIND_SUBFS
+} sc_subfs_args_t;
+
+#define PS_LOADING	1
+#define PS_RUNNING  2
+#define PS_DONE		3
+#define PS_FAILURE	4	// exception or segfault or stuff
+#define PS_KILLED	5
+typedef struct {
+	int pid;
+	int state;				// one of PS_*
+	int return_code;		// an error code if state == PS_FAILURE
+} proc_status_t;
 
 
 /* vim: set ts=4 sw=4 tw=0 noet :*/
diff --git a/src/kernel/include/vfs.h b/src/kernel/include/vfs.h
index 0890663..066211b 100644
--- a/src/kernel/include/vfs.h
+++ b/src/kernel/include/vfs.h
@@ -124,7 +124,9 @@ typedef struct {
 typedef struct fs {
 	// Filled by VFS's make_fs()
 	int refs;
-	// Filled by FS's specific make()
+	struct fs *from_fs;
+	int ok_modes;
+	// Filled by FS's specific make() - all zero in the case of a subfs
 	fs_ops_t *ops;
 	fs_ptr data;
 	// Filled by both according to what is specified for fs_node_t
@@ -158,6 +160,7 @@ fs_node_t* fs_walk_path_except_last(fs_node_t* from, const char *p, char* last_f
 void register_fs_driver(const char* name, fs_driver_ops_t *ops);
 
 fs_t* make_fs(const char* driver, fs_handle_t *source, const char* opts);
+fs_t* fs_subfs(fs_t *fs, const char *root, int ok_modes);
 bool fs_add_source(fs_t *fs, fs_handle_t *source, const char* opts);
 void ref_fs(fs_t *fs);
 void unref_fs(fs_t *fs);
diff --git a/src/kernel/user/nullfs.c b/src/kernel/user/nullfs.c
index a44e4b3..534b0ba 100644
--- a/src/kernel/user/nullfs.c
+++ b/src/kernel/user/nullfs.c
@@ -294,7 +294,7 @@ bool nullfs_d_stat(fs_node_ptr n, stat_t *st) {
 	st->access = FM_READDIR
 		| (d->fs->can_create ? FM_DCREATE : 0)
 		| (d->fs->can_move ? FM_DMOVE : 0)
-		| (d->fs->can_delete ? FM_DUNLINK : 0);
+		| (d->fs->can_delete ? FM_DDELETE : 0);
 
 	st->size = 0;
 	for (nullfs_item_t *i = d->items_list; i != 0; i = i->next)
diff --git a/src/kernel/user/syscall.c b/src/kernel/user/syscall.c
index bcf6ef4..3def3b5 100644
--- a/src/kernel/user/syscall.c
+++ b/src/kernel/user/syscall.c
@@ -29,6 +29,7 @@ static char* sc_copy_string(uint32_t s, uint32_t slen) {
 // THE SYSCALLS CODE !! //
 // ==================== //
 
+//  ---- Related to the current process's execution
 
 static uint32_t exit_sc(sc_args_t args) {
 	dbg_printf("Proc %d exit with code %d\n", current_process()->pid, args.a);
@@ -58,6 +59,8 @@ static uint32_t dbg_print_sc(sc_args_t args) {
 	return 0;
 }
 
+//  ---- Memory management related
+
 static uint32_t mmap_sc(sc_args_t args) {
 	return mmap(current_process(), (void*)args.a, args.b, args.c);
 }
@@ -78,6 +81,8 @@ static uint32_t munmap_sc(sc_args_t args) {
 	return munmap(current_process(), (void*)args.a);
 }
 
+//  ---- Accessing the VFS - filesystems
+
 static uint32_t create_sc(sc_args_t args) {
 	bool ret = false;
 
@@ -175,6 +180,8 @@ end_stat:
 	return ret;
 }
 
+//  ---- Accessing the VFS - files
+
 static uint32_t open_sc(sc_args_t args) {
 	int ret = 0;
 
@@ -260,6 +267,62 @@ static uint32_t get_mode_sc(sc_args_t args) {
 	return file_get_mode(h);
 }
 
+//  ---- Managing file systems
+
+static uint32_t make_fs_sc(sc_args_t args) {
+	return -1; // TODO
+}
+
+static uint32_t fs_add_src_sc(sc_args_t args) {
+	return -1; //TODO
+}
+
+static uint32_t fs_subfs_sc(sc_args_t args) {
+	return -1; //TODO
+}
+
+static uint32_t rm_fs_sc(sc_args_t args) {
+	return -1; //TODO
+}
+
+//  ---- Spawning new processes & giving them ressources
+
+static uint32_t new_proc_sc(sc_args_t args) {
+	return -1; //TODO
+}
+
+static uint32_t bind_fs_sc(sc_args_t args) {
+	return -1; //TODO
+}
+
+static uint32_t bind_subfs_sc(sc_args_t args) {
+	return -1; //TODO
+}
+
+static uint32_t bind_fd_sc(sc_args_t args) {
+	return -1; //TODO
+}
+
+static uint32_t proc_exec_sc(sc_args_t args) {
+	return -1; //TODO
+}
+
+static uint32_t proc_status_sc(sc_args_t args) {
+	return -1; //TODO
+}
+
+static uint32_t proc_kill_sc(sc_args_t args) {
+	return -1; //TODO
+}
+
+static uint32_t proc_wait_sc(sc_args_t args) {
+	return -1; //TODO
+}
+
+static uint32_t proc_wait_any_sc(sc_args_t args) {
+	return -1; //TODO
+}
+
 // ====================== //
 // SYSCALLS SETUP ROUTINE //
 // ====================== //
@@ -288,6 +351,21 @@ void setup_syscall_table() {
 	sc_handlers[SC_STAT_OPEN] = stat_open_sc;
 	sc_handlers[SC_IOCTL] = ioctl_sc;
 	sc_handlers[SC_GET_MODE] = get_mode_sc;
+
+	sc_handlers[SC_MAKE_FS] = make_fs_sc;
+	sc_handlers[SC_FS_ADD_SRC] = fs_add_src_sc;
+	sc_handlers[SC_SUBFS] = fs_subfs_sc;
+	sc_handlers[SC_RM_FS] = rm_fs_sc;
+
+	sc_handlers[SC_NEW_PROC] = new_proc_sc;
+	sc_handlers[SC_BIND_FS] = bind_fs_sc;
+	sc_handlers[SC_BIND_SUBFS] = bind_subfs_sc;
+	sc_handlers[SC_BIND_FD] = bind_fd_sc;
+	sc_handlers[SC_PROC_EXEC] = proc_exec_sc;
+	sc_handlers[SC_PROC_STATUS] = proc_status_sc;
+	sc_handlers[SC_PROC_KILL] = proc_kill_sc;
+	sc_handlers[SC_PROC_WAIT] = proc_wait_sc;
+	sc_handlers[SC_PROC_WAIT_ANY] = proc_wait_any_sc;
 }
 
 void syscall_handler(registers_t *regs) {
@@ -304,6 +382,7 @@ void syscall_handler(registers_t *regs) {
 				.e = regs->edi};
 			regs->eax = h(args);
 		} else {
+			dbg_printf("Unimplemented syscall %d\n", regs->eax);
 			regs->eax = -1;
 		}
 	}
diff --git a/src/kernel/user/vfs.c b/src/kernel/user/vfs.c
index 1c841f7..15f37cc 100644
--- a/src/kernel/user/vfs.c
+++ b/src/kernel/user/vfs.c
@@ -6,6 +6,11 @@
 // FILESYSTEM DRIVER REGISTERING //
 // ============================= //
 
+static fs_ops_t no_fs_ops = {
+	.shutdown = 0,
+	.add_source = 0,
+};
+
 typedef struct fs_driver {
 	const char* name;
 	fs_driver_ops_t *ops;
@@ -37,6 +42,8 @@ fs_t *make_fs(const char* drv_name, fs_handle_t *source, const char* opts) {
 	if (fs->root == 0) goto fail;
 
 	fs->refs = 1;
+	fs->from_fs = 0;
+	fs->ok_modes = FM_ALL_MODES;
 	fs->root->refs = 1;
 	fs->root->fs = fs;
 	fs->root->parent = 0;
@@ -60,6 +67,27 @@ fail:
 	return 0;
 }
 
+fs_t *fs_subfs(fs_t *fs, const char* root, int ok_modes) {
+	fs_node_t* new_root = fs_walk_path(fs->root, root);
+	if (new_root == 0) return 0;
+
+	fs_t *subfs = (fs_t*)malloc(sizeof(fs_t));
+	if (subfs == 0) return 0;
+
+	subfs->refs = 1;
+	subfs->from_fs = fs;
+	subfs->ok_modes = ok_modes & fs->ok_modes;
+
+	subfs->ops = &no_fs_ops;
+	subfs->data = 0;
+
+	subfs->root = new_root;
+
+	ref_fs(fs);
+
+	return subfs;
+}
+
 bool fs_add_source(fs_t *fs, fs_handle_t *source, const char* opts) {
 	return fs->ops->add_source && fs->ops->add_source(fs->data, source, opts);
 }
@@ -72,7 +100,8 @@ void unref_fs(fs_t *fs) {
 	fs->refs--;
 	if (fs->refs == 0) {
 		unref_fs_node(fs->root);
-		fs->ops->shutdown(fs->data);
+		if (fs->ops->shutdown) fs->ops->shutdown(fs->data);
+		if (fs->from_fs) unref_fs(fs->from_fs);
 		free(fs);
 	}
 }
@@ -260,6 +289,8 @@ fs_node_t* fs_walk_path_except_last(fs_node_t* from, const char* path, char* las
 // DOING THINGS IN FILESYSTEMS //
 
 bool fs_create(fs_t *fs, const char* file, int type) {
+	if (!(fs->ok_modes & FM_DCREATE)) return false;
+
 	char name[DIR_MAX];
 	fs_node_t *n = fs_walk_path_except_last(fs->root, file, name);
 	if (n == 0) return false;
@@ -273,6 +304,8 @@ bool fs_create(fs_t *fs, const char* file, int type) {
 }
 
 bool fs_delete(fs_t *fs, const char* file) {
+	if (!(fs->ok_modes & FM_DDELETE)) return false;
+
 	char name[DIR_MAX];
 
 	fs_node_t* n = fs_walk_path_except_last(fs->root, file, name);
@@ -292,6 +325,8 @@ bool fs_delete(fs_t *fs, const char* file) {
 }
 
 bool fs_move(fs_t *fs, const char* from, const char* to) {
+	if (!(fs->ok_modes & FM_DMOVE)) return false;
+
 	char old_name[DIR_MAX];
 	fs_node_t *old_parent = fs_walk_path_except_last(fs->root, from, old_name);
 	if (old_parent == 0) return false;
@@ -369,6 +404,8 @@ bool fs_stat(fs_t *fs, const char* file, stat_t *st) {
 // =================== //
 
 fs_handle_t* fs_open(fs_t *fs, const char* file, int mode) {
+	if (mode & ~fs->ok_modes) return 0;
+
 	fs_node_t *n = fs_walk_path(fs->root, file);
 	if (n == 0 && (mode & FM_CREATE)) {
 		if (fs_create(fs, file, FT_REGULAR)) {
diff --git a/src/lib/include/syscall.h b/src/lib/include/syscall.h
index 991b081..246c84c 100644
--- a/src/lib/include/syscall.h
+++ b/src/lib/include/syscall.h
@@ -11,6 +11,7 @@
 #include <debug.h>
 
 typedef int fd_t;
+typedef int pid_t;
 
 void dbg_print(const char* str);
 void yield();
@@ -36,6 +37,19 @@ bool stat_open(fd_t file, stat_t *s);
 int ioctl(fd_t file, int command, void* data);
 int get_mode(fd_t file);
 
-// more todo
+bool make_fs(const char* name, const char* driver, fd_t source, const char* options);
+bool fs_add_source(const char* fs, fd_t source, const char* options);
+bool fs_subfs(const char* name, const char* orig_fs, const char* root, int ok_modes);
+void fs_remove(const char* name);
+
+pid_t new_proc();
+bool bind_fs(pid_t pid, const char* new_name, const char* fs);
+bool bind_subfs(pid_t pid, const char* new_name, const char* fs, const char* root, int ok_modes);
+bool bind_fd(pid_t pid, fd_t new_fd, fd_t fd);
+bool proc_exec(pid_t pid, const char* file);
+bool proc_status(pid_t pid, proc_status_t *s);
+bool proc_kill(pid_t pid, proc_status_t *s);
+void proc_wait(pid_t pid, proc_status_t *s);
+void proc_wait_any(proc_status_t *s);
 
 /* vim: set ts=4 sw=4 tw=0 noet :*/
diff --git a/src/lib/libkogata/syscall.c b/src/lib/libkogata/syscall.c
index 52e320c..88e9aa2 100644
--- a/src/lib/libkogata/syscall.c
+++ b/src/lib/libkogata/syscall.c
@@ -90,4 +90,77 @@ int get_mode(fd_t file) {
 	return call(SC_GET_MODE, file, 0, 0, 0, 0);
 }
 
+bool make_fs(const char* name, const char* driver, fd_t source, const char* options) {
+	sc_make_fs_args_t args = {
+		.driver = driver,
+		.driver_strlen = strlen(driver),
+		.fs_name = name,
+		.fs_name_strlen = strlen(name),
+		.source_fd = source,
+		.opts = options,
+		.opts_strlen = strlen(options),
+	};
+	return call(SC_MAKE_FS, (uint32_t)&args, 0, 0, 0, 0);
+}
+bool fs_add_source(const char* fs, fd_t source, const char* options) {
+	return call(SC_FS_ADD_SRC, (uint32_t)fs, strlen(fs), source, (uint32_t)options, strlen(options));
+}
+bool fs_subfs(const char* name, const char* orig_fs, const char* root, int ok_modes) {
+	sc_subfs_args_t args = {
+		.new_name = name,
+		.new_name_strlen = strlen(name),
+		.from_fs = orig_fs,
+		.from_fs_strlen = strlen(orig_fs),
+		.root = root,
+		.root_strlen = strlen(root),
+		.ok_modes = ok_modes,
+		.bind_to_pid = 0
+	};
+	return call(SC_SUBFS, (uint32_t)&args, 0, 0, 0, 0);
+}
+void fs_remove(const char* name) {
+	call(SC_RM_FS, (uint32_t)name, strlen(name), 0, 0, 0);
+}
+
+pid_t new_proc() {
+	return call(SC_NEW_PROC, 0, 0, 0, 0, 0);
+}
+bool bind_fs(pid_t pid, const char* new_name, const char* fs) {
+	return call(SC_BIND_FS, pid, (uint32_t)new_name, strlen(new_name), (uint32_t)fs, strlen(fs));
+}
+bool bind_subfs(pid_t pid, const char* new_name, const char* orig_fs, const char* root, int ok_modes) {
+	sc_subfs_args_t args = {
+		.new_name = new_name,
+		.new_name_strlen = strlen(new_name),
+		.from_fs = orig_fs,
+		.from_fs_strlen = strlen(orig_fs),
+		.root = root,
+		.root_strlen = strlen(root),
+		.ok_modes = ok_modes,
+		.bind_to_pid = pid
+	};
+	return call(SC_BIND_SUBFS, (uint32_t)&args, 0, 0, 0, 0);
+}
+bool bind_fd(pid_t pid, fd_t new_fd, fd_t fd) {
+	return call(SC_BIND_FD, new_fd, fd, 0, 0, 0);
+}
+bool proc_exec(pid_t pid, const char* file) {
+	return call(SC_PROC_EXEC, pid, (uint32_t)file, strlen(file), 0, 0);
+}
+bool proc_status(pid_t pid, proc_status_t *s) {
+	return call(SC_PROC_STATUS, pid, (uint32_t)s, 0, 0, 0);
+}
+bool proc_kill(pid_t pid, proc_status_t *s) {
+	return call(SC_PROC_KILL, pid, (uint32_t)s, 0, 0, 0);
+}
+void proc_wait(pid_t pid, proc_status_t *s) {
+	call(SC_PROC_WAIT, pid, (uint32_t)s, 0, 0, 0);
+}
+void proc_wait_any(proc_status_t *s) {
+	call(SC_PROC_WAIT_ANY, (uint32_t)s, 0, 0, 0, 0);
+}
+
+
+
+
 /* vim: set ts=4 sw=4 tw=0 noet :*/