LAB 4 IS DONE.

lab/inc/env.h

@@ -0,0 +1,72 @@
+/* See COPYRIGHT for copyright information. */
+
+#ifndef JOS_INC_ENV_H
+#define JOS_INC_ENV_H
+
+#include <inc/types.h>
+#include <inc/trap.h>
+#include <inc/memlayout.h>
+
+typedef int32_t envid_t;
+
+// An environment ID 'envid_t' has three parts:
+//
+// +1+---------------21-----------------+--------10--------+
+// |0|          Uniqueifier             |   Environment    |
+// | |                                  |      Index       |
+// +------------------------------------+------------------+
+//                                       \--- ENVX(eid) --/
+//
+// The environment index ENVX(eid) equals the environment's index in the
+// 'envs[]' array.  The uniqueifier distinguishes environments that were
+// created at different times, but share the same environment index.
+//
+// All real environments are greater than 0 (so the sign bit is zero).
+// envid_ts less than 0 signify errors.  The envid_t == 0 is special, and
+// stands for the current environment.
+
+#define LOG2NENV		10
+#define NENV			(1 << LOG2NENV)
+#define ENVX(envid)		((envid) & (NENV - 1))
+
+// Values of env_status in struct Env
+enum {
+	ENV_FREE = 0,
+	ENV_DYING,
+	ENV_RUNNABLE,
+	ENV_RUNNING,
+	ENV_NOT_RUNNABLE
+};
+
+// Special environment types
+enum EnvType {
+	ENV_TYPE_USER = 0,
+};
+
+struct Env {
+	struct Trapframe env_tf;	// Saved registers
+	struct Env *env_link;		// Next free Env
+	envid_t env_id;			// Unique environment identifier
+	envid_t env_parent_id;		// env_id of this env's parent
+	enum EnvType env_type;		// Indicates special system environments
+	unsigned env_status;		// Status of the environment
+	uint32_t env_runs;		// Number of times environment has run
+	int env_cpunum;			// The CPU that the env is running on
+
+	// Address space
+	pde_t *env_pgdir;		// Kernel virtual address of page dir
+
+	// Exception handling
+	void *env_pgfault_upcall;	// Page fault upcall entry point
+
+	// Lab 4 challenge
+	// uint32_t env_priority;
+	// Lab 4 IPC
+	bool env_ipc_recving;		// Env is blocked receiving
+	void *env_ipc_dstva;		// VA at which to map received page
+	uint32_t env_ipc_value;		// Data value sent to us
+	envid_t env_ipc_from;		// envid of the sender
+	int env_ipc_perm;		// Perm of page mapping received
+};
+
+#endif // !JOS_INC_ENV_H