Fixed minor faults during close path.

FIXME:
write/close/open/read sequence does not read the initially written data.
Investigate.

tasks/fs0/src/syscalls.c

@@ -93,7 +93,8 @@ struct vnode *vfs_create(struct tcb *task, struct pathdata *pdata,
 	return newnode;
 }
 
-/* Pager notifies vfs about a closed file descriptor.
+/*
+ * Pager notifies vfs about a closed file descriptor.
  *
  * FIXME: fsync + close could be done under a single "close" ipc
  * from pager. Currently there are 2 ipcs: 1 fsync + 1 fd close. 
@@ -103,9 +104,10 @@ int pager_sys_close(l4id_t sender, l4id_t closer, int fd)
 	struct tcb *task;
 	int err;
 
-	BUG_ON(!(task = find_task(sender)));
+	BUG_ON(!(task = find_task(closer)));
 
-	if ((err = id_del(task->fdpool, task->fd[fd])) < 0) {
+	printf("Deleting fd: %d\n", fd);
+	if ((err = id_del(task->fdpool, fd)) < 0) {
 		printf("%s: Error releasing fd identifier.\n",
 		       __FUNCTION__);
 		l4_ipc_return(err);

tasks/mm0/include/vm_area.h

@@ -34,7 +34,7 @@
 #define VMA_ANONYMOUS			(1 << 5)
 /* Private copy of a file */
 #define VMA_PRIVATE			(1 << 6)
-/* Copy-on-write semantics */
+/* For wired pages */
 #define VMA_FIXED			(1 << 7)
 /* Set when the page is dirty in cache but not written to disk */
 #define VM_DIRTY			(1 << 8)

tasks/mm0/src/file.c

@@ -146,7 +146,7 @@ int vfs_receive_sys_open(l4id_t sender, l4id_t opener, int fd,
 
 /*
  * Inserts the page to vmfile's list in order of page frame offset.
- * We use an ordered list instead of a radix or btree for now.
+ * We use an ordered list instead of a better data structure for now.
  */
 int insert_page_olist(struct page *this, struct vm_object *vmo)
 {
@@ -321,7 +321,7 @@ int flush_file_pages(struct vm_file *f)
 	return 0;
 }
 
-/* Given a task and fd syncs all IO on it */
+/* Given a task and fd, syncs all IO on it */
 int fsync_common(l4id_t sender, int fd)
 {
 	struct vm_file *f;
@@ -352,6 +352,8 @@ int fd_close(l4id_t sender, int fd)
 	/* Get the task */
 	BUG_ON(!(task = find_task(sender)));
 
+	printf("%s: Closing fd: %d on task %d\n", __FUNCTION__,
+	       fd, task->tid);
 	if ((err = vfs_close(task->tid, fd)) < 0)
 		return err;
 
@@ -364,16 +366,21 @@ int fd_close(l4id_t sender, int fd)
 
 int sys_close(l4id_t sender, int fd)
 {
-	int err;
+	int retval;
 
 	/* Sync the file and update stats */
-	if ((err = fsync_common(sender, fd)) < 0) {
+	if ((retval = fsync_common(sender, fd)) < 0) {
-		l4_ipc_return(err);
+		l4_ipc_return(retval);
 		return 0;
 	}
 	
 	/* Close the file descriptor. */
-	return	fd_close(sender, fd);
+	retval = fd_close(sender, fd);
+	printf("%s: Closed fd %d. Returning %d\n",
+	       __TASKNAME__, fd, retval);
+	l4_ipc_return(retval);
+
+	return 0;
 }
 
 int sys_fsync(l4id_t sender, int fd)

tasks/test0/include/tests.h

@@ -7,5 +7,6 @@ int shmtest(void);
 int mmaptest(void);
 int dirtest(void);
 int fileio(void);
+int fileio2(void);
 
 #endif /* __TEST0_TESTS_H__ */

tasks/test0/main.c

@@ -28,7 +28,18 @@ void main(void)
 	wait_pager(0);
 
 	dirtest();
-	fileio();
+	printf("File IO test 1:\n");
+	if (fileio() == 0)
+		printf("-- PASSED --\n");
+	else
+		printf("-- FAILED --\n");
+
+	printf("File IO test 2:\n");
+	if (fileio2() == 0)
+		printf("-- PASSED --\n");
+	else
+		printf("-- FAILED --\n");
+
 	while (1)
 		wait_pager(0);
 #if 0

tasks/test0/src/fileio.c

@@ -7,6 +7,63 @@
 #include <string.h>
 #include <tests.h>
 
+int fileio2(void)
+{
+	int fd;
+	ssize_t cnt;
+	int err;
+	char buf[128];
+	off_t offset;
+
+	char *str = "I WROTE TO THIS FILE\n";
+
+	if ((fd = open("/home/bahadir/newfile2.txt", O_RDWR | O_CREAT | O_TRUNC, S_IRWXU)) < 0) {
+		perror("OPEN");
+		return -1;
+	}
+	printf("Created newfile.txt\n");
+
+	printf("%s: write.\n", __TASKNAME__);
+	if ((int)(cnt = write(fd, str, strlen(str))) < 0) {
+		perror("WRITE");
+		return -1;
+	}
+	printf("%s: close.\n", __TASKNAME__);
+	if ((err = close(fd)) < 0) {
+		printf("Close failed.\n");
+		perror("CLOSE");
+		return -1;
+	}
+	printf("%s: re-open.\n", __TASKNAME__);
+	if ((fd = open("/home/bahadir/newfile2.txt", O_RDWR, S_IRWXU)) < 0) {
+		perror("OPEN");
+		return -1;
+	}
+
+	printf("%s: lseek.\n", __TASKNAME__);
+	if ((int)(offset = lseek(fd, 0, SEEK_SET)) < 0) {
+		perror("LSEEK");
+		return -1;
+	}
+	printf("%s: read.\n", __TASKNAME__);
+	if ((int)(cnt = read(fd, buf, strlen(str))) < 0) {
+		perror("READ");
+		return -1;
+	}
+
+	printf("Read: %d bytes from file.\n", cnt);
+	if (cnt) {
+		printf("Read string: %s\n", buf);
+	}
+
+	if ((err = close(fd)) < 0) {
+		perror("CLOSE");
+		return -1;
+	}
+
+	return 0;
+}
+
 int fileio(void)
 {
 	int fd;
@@ -56,9 +113,18 @@ int fileio(void)
 #if defined(HOST_TESTS)
 int main(void)
 {
-	printf("File IO test:\n");
+	printf("File IO test 1:\n");
 	if (fileio() == 0)
 		printf("-- PASSED --\n");
+	else
+		printf("-- FAILED --\n");
+
+	printf("File IO test 2:\n");
+	if (fileio2() == 0)
+		printf("-- PASSED --\n");
+	else
+		printf("-- FAILED --\n");
+
 
 	return 0;
 }