syscall lab finished

kernel/defs.h

@@ -63,6 +63,7 @@ void ramdiskrw(struct buf *);
 void *kalloc(void);
 void kfree(void *);
 void kinit(void);
+int freemem(void);
 
 // log.c
 void initlog(int, struct superblock *);
@@ -106,6 +107,7 @@ void yield(void);
 int either_copyout(int user_dst, uint64 dst, void *src, uint64 len);
 int either_copyin(void *dst, int user_src, uint64 src, uint64 len);
 void procdump(void);
+int proc_size(void);
 
 // swtch.S
 void swtch(struct context *, struct context *);

kernel/kalloc.c

@@ -7,6 +7,7 @@
 #include "memlayout.h"
 #include "spinlock.h"
 #include "riscv.h"
+#include "proc.h"
 #include "defs.h"
 
 void freerange(void *pa_start, void *pa_end);
@@ -80,3 +81,17 @@ kalloc(void)
     memset((char*)r, 5, PGSIZE); // fill with junk
   return (void*)r;
 }
+
+int 
+freemem(void)
+{
+  struct run* p = kmem.freelist;
+  uint64 num = 0;
+  while (p) {
+    num += 1;
+    p = p->next;
+  }
+  return num * PGSIZE;
+}
+
+

kernel/proc.c

@@ -691,3 +691,13 @@ procdump(void)
     printf("\n");
   }
 }
+
+int
+proc_size()
+{
+  int i =0, n = 0;
+  for (; i < NPROC; ++i) {
+    if (proc[i].state != UNUSED) n += 1;
+  }
+  return n;
+}

kernel/syscall.c

@@ -8,9 +8,9 @@
 #include "defs.h"
 
 // 保留系统调用别名
-char* syscalls_name[24] = {"", "fork", "exit", "wait", "pipe", "read", "kill", "exec",
+char* syscalls_name[25] = {"", "fork", "exit", "wait", "pipe", "read", "kill", "exec",
                       "fstat", "chdir", "dup", "getpid", "sbrk", "sleep", "uptime",
-                      "open", "write", "mknod", "unlink", "link", "mkdir", "close", "trace"};
+                      "open", "write", "mknod", "unlink", "link", "mkdir", "close", "trace", "sysinfo"};
 
 // Fetch the uint64 at addr from the current process.
 int
@@ -107,6 +107,7 @@ extern uint64 sys_link(void);
 extern uint64 sys_mkdir(void);
 extern uint64 sys_close(void);
 extern uint64 sys_trace(void);
+extern uint64 sys_sysinfo(void);
 
 // An array mapping syscall numbers from syscall.h
 // to the function that handles the system call.
@@ -133,6 +134,7 @@ static uint64 (*syscalls[])(void) = {
 [SYS_mkdir]   sys_mkdir,
 [SYS_close]   sys_close,
 [SYS_trace]   sys_trace,
+[SYS_sysinfo]   sys_sysinfo,
 };
 
 void

kernel/syscall.h

@@ -21,3 +21,4 @@
 #define SYS_mkdir  20
 #define SYS_close  21
 #define SYS_trace  22
+#define SYS_sysinfo 23

kernel/sysinfo.h

@@ -0,0 +1,6 @@
+#include "kernel/types.h"
+struct sysinfo {
+  uint64 freemem;
+  uint64 nproc;
+  uint64 unused_proc_num;
+};

kernel/sysproc.c

@@ -5,6 +5,7 @@
 #include "memlayout.h"
 #include "spinlock.h"
 #include "proc.h"
+#include "sysinfo.h"
 
 uint64
 sys_exit(void)
@@ -101,3 +102,19 @@ sys_trace(void)
   myproc()->tracemask = n;
   return 0;
 }
+
+uint64
+sys_sysinfo(void)
+{
+  struct sysinfo info;
+  uint64 addr;
+  argaddr(0, &addr);
+  if (addr < 0) return -1;
+  struct proc* p = myproc();
+  info.nproc = proc_size();
+  info.freemem = freemem();
+  info.unused_proc_num = NPROC - info.nproc;
+  if (copyout(p->pagetable, addr, (char*)&info, sizeof(info)) < 0)
+    return -1;
+  return 0;
+}