Added an extended ipc return library function.

conts/libl4/include/l4lib/arch-arm/syslib.h

@@ -110,6 +110,23 @@ static inline void l4_set_tag(unsigned int tag)
 	write_mr(MR_TAG, tag_flags);
 }
 
+/* Servers:
+ * Sets the message register for returning errors back to client task.
+ * These are usually posix error codes.
+ */
+static inline void l4_set_retval(int retval)
+{
+	write_mr(MR_RETURN, retval);
+}
+
+/* Clients:
+ * Learn result of request.
+ */
+static inline int l4_get_retval(void)
+{
+	return read_mr(MR_RETURN);
+}
+
 /*
  * If we're about to do another ipc, this saves the last ipc's
  * parameters such as the sender and tag information.
@@ -195,6 +212,39 @@ static inline int l4_receive_extended(l4id_t from, unsigned int size, void *buf)
 	return l4_ipc(L4_NILTHREAD, from, flags);
 }
 
+/*
+ * Return result value as extended IPC.
+ *
+ * Extended IPC copies up to 2KB user address space buffers.
+ * Along with such an ipc, a return value is sent using a primary
+ * mr that is used as the return register.
+ *
+ * It may not be desirable to return a payload on certain conditions,
+ * (such as an error return value) So a nopayload field is provided.
+ */
+static inline int l4_return_extended(int retval, unsigned int size,
+				     void *buf, int nopayload)
+{
+	unsigned int flags = 0;
+	l4id_t sender = l4_get_sender();
+
+	l4_set_retval(retval);
+
+	/* Set up flags word for extended ipc */
+	flags = l4_set_ipc_flags(flags, L4_IPC_FLAGS_EXTENDED);
+	flags = l4_set_ipc_msg_index(flags, L4SYS_ARG0);
+
+	/* Write buffer pointer to MR index that we specified */
+	write_mr(L4SYS_ARG0, (unsigned long)buf);
+
+	if (nopayload)
+		flags = l4_set_ipc_size(flags, 0);
+	else
+		flags = l4_set_ipc_size(flags, size);
+
+	return l4_ipc(sender, L4_NILTHREAD, flags);
+}
+
 static inline int l4_sendrecv_extended(l4id_t to, l4id_t from,
 				       unsigned int tag, void *buf)
 {
@@ -226,23 +276,6 @@ static inline int l4_receive(l4id_t from)
 	return l4_ipc(L4_NILTHREAD, from, 0);
 }
 
-/* Servers:
- * Sets the message register for returning errors back to client task.
- * These are usually posix error codes.
- */
-static inline void l4_set_retval(int retval)
-{
-	write_mr(MR_RETURN, retval);
-}
-
-/* Clients:
- * Learn result of request.
- */
-static inline int l4_get_retval(void)
-{
-	return read_mr(MR_RETURN);
-}
-
 static inline void l4_print_mrs()
 {
 	printf("Message registers: 0x%x, 0x%x, 0x%x, 0x%x, 0x%x, 0x%x\n",
@@ -259,7 +292,7 @@ static inline int l4_ipc_return(int retval)
 
 	l4_set_retval(retval);
 
-	/* Setting the tag may overwrite retval so we l4_send without tagging */
+	/* Setting the tag would overwrite retval so we l4_send without tagging */
 	return l4_ipc(sender, L4_NILTHREAD, 0);
 }
 

conts/posix/libposix/chdir.c

@@ -24,8 +24,6 @@ static inline int l4_chdir(const char *pathname)
 
 	utcb_full_strcpy_from(pathname);
 
-	write_mr(L4SYS_ARG0, (unsigned long)utcb_full_buffer());
-
 	/* Call pager with shmget() request. Check ipc error. */
 	if ((fd = l4_sendrecv_full(VFS_TID, VFS_TID, L4_IPC_TAG_CHDIR)) < 0) {
 		print_err("%s: L4 IPC Error: %d.\n", __FUNCTION__, fd);

conts/posix/libposix/mkdir.c

@@ -26,8 +26,7 @@ static inline int l4_mkdir(const char *pathname, mode_t mode)
 
 	// write_mr(L4SYS_ARG0, (unsigned long)pathname);
 	utcb_full_strcpy_from(pathname);
-	write_mr(L4SYS_ARG0, (unsigned long)utcb_full_buffer());
-	write_mr(L4SYS_ARG1, (u32)mode);
+	write_mr(L4SYS_ARG0, (u32)mode);
 
 	/* Call pager with shmget() request. Check ipc error. */
 	if ((fd = l4_sendrecv_full(PAGER_TID, PAGER_TID, L4_IPC_TAG_MKDIR)) < 0) {

conts/posix/libposix/read.c

@@ -15,7 +15,7 @@
 #include <l4lib/os/posix/readdir.h>
 #include <l4/macros.h>
 #include INC_GLUE(memory.h)
-#include <shpage.h>
+#include INC_GLUE(message.h)
 #include <libposix.h>
 
 /*
@@ -29,6 +29,37 @@
  * Or do it just like read()
  */
 static inline int l4_readdir(int fd, void *buf, size_t count)
+{
+	int cnt, err;
+
+	write_mr(L4SYS_ARG0, fd);
+	write_mr(L4SYS_ARG1, count);
+
+	/* Call pager with readdir() request. Check ipc error. */
+	if ((err = l4_send(PAGER_TID, L4_IPC_TAG_READDIR)) < 0) {
+		print_err("%s: L4 IPC Error: %d.\n", __FUNCTION__, err);
+		return err;
+	}
+
+	/* Call pager with readdir() request. Check ipc error. */
+	if ((err = l4_receive_extended(PAGER_TID,
+				       L4_IPC_EXTENDED_MAX_SIZE,
+				       buf)) < 0) {
+		print_err("%s: L4 Extended IPC error: %d.\n", __FUNCTION__, err);
+		return err;
+	}
+
+	/* Check if syscall itself was successful */
+	if ((cnt = l4_get_retval()) < 0) {
+		print_err("%s: READDIR Error: %d.\n", __FUNCTION__, (int)cnt);
+		return cnt;
+	}
+
+	return cnt;
+}
+
+#if 0
+static inline int l4_readdir(int fd, void *buf, size_t count)
 {
 	int cnt;
 
@@ -50,7 +81,7 @@ static inline int l4_readdir(int fd, void *buf, size_t count)
 
 	return cnt;
 }
-
+#endif
 static inline int l4_read(int fd, void *buf, size_t count)
 {
 	int cnt;

conts/posix/mm0/include/syscalls.h

@@ -38,7 +38,7 @@ void sys_exit(struct tcb *task, int status);
 
 /* Posix calls */
 int sys_open(struct tcb *sender, const char *pathname, int flags, u32 mode);
-int sys_readdir(struct tcb *sender, int fd, void *buf, int count);
+int sys_readdir(struct tcb *sender, int fd, int count, char *dirbuf);
 int sys_mkdir(struct tcb *sender, const char *pathname, unsigned int mode);
 int sys_chdir(struct tcb *sender, const char *pathname);
 

conts/posix/mm0/main.c

@@ -148,26 +148,32 @@ void handle_requests(void)
 		ret = sys_execve(sender, (char *)mr[0],
 				 (char **)mr[1], (char **)mr[2]);
 		if (ret < 0)
-			break;	/* We origy for errors */
+			break;	/* We reply for errors */
 		else
 			return; /* else we're done */
 	}
 
-	/* FIXME: Fix all these syscalls to read any buffer data from the caller task's utcb. */
+	/*
+	 * FIXME: Fix all these syscalls to read any
+	 * buffer data from the caller task's utcb.
+	 */
+
 	/* FS0 System calls */
 	case L4_IPC_TAG_OPEN:
 		ret = sys_open(sender, utcb_full_buffer(), (int)mr[0], (unsigned int)mr[1]);
 		break;
 	case L4_IPC_TAG_MKDIR:
-		ret = sys_mkdir(sender, (const char *)mr[0], (unsigned int)mr[1]);
+		ret = sys_mkdir(sender, utcb_full_buffer(), (unsigned int)mr[0]);
 		break;
 	case L4_IPC_TAG_CHDIR:
-		ret = sys_chdir(sender, (const char *)mr[0]);
+		ret = sys_chdir(sender, utcb_full_buffer());
 		break;
-	case L4_IPC_TAG_READDIR:
-		ret = sys_readdir(sender, (int)mr[0], (void *)mr[1], (int)mr[2]);
-		break;
-
+	case L4_IPC_TAG_READDIR: {
+		char dirbuf[L4_IPC_EXTENDED_MAX_SIZE];
+		ret = sys_readdir(sender, (int)mr[0], (int)mr[1], dirbuf);
+		l4_return_extended(ret, L4_IPC_EXTENDED_MAX_SIZE, dirbuf, ret < 0);
+		return;
+	}
 	default:
 		printf("%s: Unrecognised ipc tag (%d) "
 		       "received from (%d). Full mr reading: "

conts/posix/mm0/mm/file.c

@@ -31,6 +31,8 @@
 #include <path.h>
 #include <syscalls.h>
 
+#include INC_GLUE(message.h)
+
 /* Copy from one page's buffer into another page */
 int page_copy(struct page *dst, struct page *src,
 	      unsigned long dst_offset, unsigned long src_offset,
@@ -1173,17 +1175,22 @@ int fill_dirent(void *buf, unsigned long vnum, int offset, char *name)
  *
  * FIXME: Ensure buf is in shared utcb, and count does not exceed it.
  */
-int sys_readdir(struct tcb *t, int fd, void *buf, int count)
+int sys_readdir(struct tcb *t, int fd, int count, char *dirbuf)
 {
 	int dirent_size = sizeof(struct dirent);
 	int total = 0, nbytes = 0;
 	unsigned long vnum;
 	struct vnode *v;
 	struct dentry *d;
+	char *buf = dirbuf;
 
 	// printf("%s/%s\n", __TASKNAME__, __FUNCTION__);
 
-	BUG(); /* Do this by extended ipc !!! */
+	/*
+	 * FIXME:
+	 * Add dirbuf overflow checking
+	 */
+
 	/* Check address is in task's utcb */
 
 	if (fd < 0 || fd > TASK_FILES_MAX || !t->files->fd[fd].vnum)

include/l4/glue/arm/message.h

@@ -85,7 +85,7 @@
 #define L4_IPC_EXTENDED_MAX_SIZE	(SZ_1K*2)
 
 /* Primaries aren't used for memcopy. Those ops use this as a parameter */
-#define L4_UTCB_FULL_BUFFER_SIZE	(MR_REST * sizeof(int)) 
+#define L4_UTCB_FULL_BUFFER_SIZE	(MR_REST * sizeof(int))
 
 #include INC_GLUE(memlayout.h)
 

src/api/ipc.c

@@ -131,6 +131,8 @@ int ipc_msg_copy(struct ktcb *to, struct ktcb *from)
 		break;
 	case IPC_FLAGS_EXTENDED:
 		if (send_ipc_type == IPC_FLAGS_EXTENDED)
+			/* We do a short copy as well. */
+			ret = ipc_short_copy(to, from);
 			ret = ipc_extended_copy(to, from);
 		if (send_ipc_type == IPC_FLAGS_SHORT)
 			ret = -ENOIPC;