3 files changed, 19 insertions, 2 deletions

diff --git a/src/kernel/vfs/mount.c b/src/kernel/vfs/mount.c
index c962ba5..423bf10 100644
--- a/src/kernel/vfs/mount.c
+++ b/src/kernel/vfs/mount.c
@@ -6,6 +6,7 @@ struct vfs_mount *vfs_mount_seed(void) {
 	struct vfs_mount   *mount   = kmalloc(sizeof *mount);
 	struct vfs_backend *backend = kmalloc(sizeof *backend);
 	backend->type = VFS_BACK_ROOT;
+	backend->potential_handlers = 1;
 	*mount = (struct vfs_mount){
 		.prev = NULL,
 		.prefix = "",
diff --git a/src/kernel/vfs/request.c b/src/kernel/vfs/request.c
index 687f456..277c353 100644
--- a/src/kernel/vfs/request.c
+++ b/src/kernel/vfs/request.c
@@ -14,7 +14,7 @@ int vfs_request_create(struct vfs_request req_) {
 	process_current->waits4fs.req = req_;
 	req = &process_current->waits4fs.req;
 
-	if (!req->backend)
+	if (!req->backend || !req->backend->potential_handlers)
 		return vfs_request_finish(req, -1);
 
 	switch (req->backend->type) {
@@ -89,10 +89,22 @@ int vfs_request_finish(struct vfs_request *req, int ret) {
 		ret = handle;
 	}
 
-	if (req->input.kern)  kfree(req->input.buf_kern);
+	if (req->input.kern)
+		kfree(req->input.buf_kern);
 
 	assert(req->caller->state == PS_WAITS4FS || req->caller->state == PS_WAITS4IRQ);
 	process_transition(req->caller, PS_RUNNING);
 	regs_savereturn(&req->caller->regs, ret);
 	return ret;
 }
+
+void vfs_request_cancel(struct vfs_request *req, int ret) {
+	if (req->input.kern)
+		kfree(req->input.buf_kern);
+
+	// ret must always be negative, so it won't be confused with a success
+	if (ret > 0) ret = -ret;
+	if (ret == 0) ret = -1;
+	regs_savereturn(&req->caller->regs, ret);
+	process_transition(req->caller, PS_RUNNING);
+}
diff --git a/src/kernel/vfs/request.h b/src/kernel/vfs/request.h
index ce5a7fb..1e3ef60 100644
--- a/src/kernel/vfs/request.h
+++ b/src/kernel/vfs/request.h
@@ -13,6 +13,8 @@ enum vfs_backend_type {
 struct vfs_backend {
 	enum vfs_backend_type type;
 
+	size_t potential_handlers; // 0 - orphaned
+
 	// only used with VFS_BACK_USER
 	struct process *handler;
 	struct process *queue;
@@ -45,3 +47,5 @@ struct vfs_request {
 int vfs_request_create(struct vfs_request);
 int vfs_request_accept(struct vfs_request *);
 int vfs_request_finish(struct vfs_request *, int ret);
+
+void vfs_request_cancel(struct vfs_request *, int ret);