Removed allocation of utcb shared pages by mm0 completely.

- Now libl4 has no references to utcb page or shmat etc.
- Pager does not deal with special case utcb page allocation.
  It instead allocates a shared page from shm memory pool.
- All tasks working to original standard.

Next:
- Add per-thread utcb allocation from the kernel
- Add larger register file for standard ipc
- Add long ipc (up to 1Kb)

tasks/libposix/chdir.c

@@ -3,6 +3,7 @@
  *
  * Copyright (C) 2008 Bahadir Balban
  */
+#include <shpage.h>
 #include <errno.h>
 #include <stdio.h>
 #include <stdarg.h>
@@ -21,8 +22,8 @@ static inline int l4_chdir(const char *pathname)
 	int fd;
 
 	// write_mr(L4SYS_ARG0, (unsigned long)pathname);
-	copy_to_utcb((void *)pathname, 0, strlen(pathname) + 1);
-	write_mr(L4SYS_ARG0, (unsigned long)utcb_page);
+	copy_to_shpage((void *)pathname, 0, strlen(pathname) + 1);
+	write_mr(L4SYS_ARG0, (unsigned long)shared_page);
 
 	/* Call pager with shmget() request. Check ipc error. */
 	if ((fd = l4_sendrecv(VFS_TID, VFS_TID, L4_IPC_TAG_CHDIR)) < 0) {

tasks/libposix/fork.c

@@ -12,6 +12,7 @@
 #include <l4lib/utcb.h>
 #include <l4/macros.h>
 #include INC_GLUE(memory.h)
+#include <posix_init.h>
 
 static inline int l4_fork(void)
 {
@@ -40,9 +41,12 @@ int fork(void)
 		return -1;
 	}
 
-	/* If we're a child, we need to initialise the utcb page */
+	/*
+	 * If we're a child, we need to initialise the default
+	 * shared page via posix_init()
+	 */
 	if (ret == 0)
-		utcb_init();
+		posix_init();
 
 	return ret;
 }

tasks/libposix/include/posix/posix_init.h

@@ -0,0 +1,6 @@
+#ifndef __POSIX_INIT_H__
+#define __POSIX_INIT_H__
+
+void posix_init(void);
+
+#endif /* __POSIX_INIT_H__ */

tasks/libposix/include/posix/shpage.h

@@ -0,0 +1,45 @@
+/*
+ * A default shared page is used by every thread
+ * to pass large data for system calls.
+ *
+ * This file contains relevant shpage definitions.
+ */
+#ifndef __LIBPOSIX_SHPAGE_H__
+#define __LIBPOSIX_SHPAGE_H__
+
+#include <l4/macros.h>
+#include <l4lib/arch/syscalls.h>
+#include <l4lib/arch/syslib.h>
+#include <l4lib/ipcdefs.h>
+#include <l4lib/utcb.h>
+#include INC_GLUE(memory.h)
+
+extern void *shared_page;
+
+int shared_page_init(void);
+
+/*
+ * Arguments that are too large to fit in message registers are
+ * copied onto another area that is still on the utcb, and the servers
+ * map-in the task utcb and read those arguments from there.
+ */
+
+static inline int copy_to_shpage(void *arg, int offset, int size)
+{
+	if (offset + size > PAGE_SIZE)
+		return -1;
+
+	memcpy(shared_page + offset, arg, size);
+	return 0;
+}
+
+static inline int copy_from_shpage(void *buf, int offset, int size)
+{
+	if (offset + size > PAGE_SIZE)
+		return -1;
+
+	memcpy(buf, shared_page + offset, size);
+	return 0;
+}
+
+#endif /* __LIBPOSIX_SHPAGE_H__ */

tasks/libposix/init.c

@@ -1,79 +1,30 @@
 /*
- * Shared page initialisation of posix-like tasks.
+ * Main entry point for posix services and applications.
  *
- * POSIX tasks currently use a default shared page for communciation.
- * This could have been also done by long ipc calls.
+ * Copyright (C) 2007-2009 Bahadir Balban
  */
 
-/*
- * Shared page for this task. Used for passing data among ipc
- * parties when message registers are not big enough. Every thread
- * has right to own one, and it has an address unique to every
- * thread. It must be explicitly mapped by both parties of the ipc
- * in order to be useful.
- */
-void *shared_page;
+#include <shpage.h>
+#include <posix_init.h>
 
-/*
- * Obtains a unique address for the task's shared page. Note this
- * just returns the address. This address is used as an shm key
- * to map it via shmget()/shmat() later on.
- */
-static void *shared_page_address(void)
+void posix_init(void)
 {
-	void *addr;
-	int err;
-
-	/* We're asking it for ourself. */
-	write_mr(L4SYS_ARG0, self_tid());
-
-	/* Call pager with utcb address request. Check ipc error. */
-	if ((err = l4_sendrecv(PAGER_TID, PAGER_TID,
-			       L4_IPC_TAG_DEFAULT_SHPAGE)) < 0) {
-		printf("%s: L4 IPC Error: %d.\n", __FUNCTION__, err);
-		return PTR_ERR(err);
-	}
-
-	/* Check if syscall itself was successful */
-	if (IS_ERR(addr = (void *)l4_get_retval())) {
-		printf("%s: Request UTCB Address Error: %d.\n",
-		       __FUNCTION__, (int)addr);
-		return addr;
-	}
-
-	return addr;
+	/* Non-pager tasks initialise their shared communication page */
+	if (self_tid() != PAGER_TID)
+		shared_page_init();
 }
 
+int main(void);
+
 /*
- * Initialises a non-pager task's default shared memory page
- * using posix semantics. Used during task initialisation
- * and by child tasks after a fork.
+ * Entry point for posix services container.
+ *
+ * This is executed by all posix system services and tasks
+ * that run in this container.
  */
-int shared_page_init(void)
+void __container_init(void)
 {
-	int shmid;
-	void *shmaddr;
-
-	/*
-	 * Initialise shared page only if we're not the pager.
-	 * The pager does it differently for itself.
-	 */
-	BUG_ON(self_tid() == PAGER_TID);
-
-	/* Obtain our utcb page address */
-	utcb_page = l4_utcb_page();
-	//printf("%s: UTCB Read from mm0 as: 0x%x\n", __FUNCTION__,
-	//       (unsigned long)utcb_page);
-
-	/* Use it as a key to create a shared memory region */
-	BUG_ON((shmid = shmget((key_t)utcb_page,
-			       PAGE_SIZE, IPC_CREAT)) < 0);
-
-	/* Attach to the region */
-	BUG_ON((shmaddr = shmat(shmid, utcb_page, 0)) < 0);
-	BUG_ON(shmaddr != utcb_page);
-
-	return 0;
+	posix_init();
+	main();
 }
 
-

tasks/libposix/mkdir.c

@@ -3,6 +3,7 @@
  *
  * Copyright (C) 2008 Bahadir Balban
  */
+#include <shpage.h>
 #include <errno.h>
 #include <stdio.h>
 #include <stdarg.h>
@@ -23,8 +24,8 @@ static inline int l4_mkdir(const char *pathname, mode_t mode)
 	int fd;
 
 	// write_mr(L4SYS_ARG0, (unsigned long)pathname);
-	copy_to_utcb((void *)pathname, 0, strlen(pathname) + 1);
-	write_mr(L4SYS_ARG0, (unsigned long)utcb_page);
+	copy_to_shpage((void *)pathname, 0, strlen(pathname) + 1);
+	write_mr(L4SYS_ARG0, (unsigned long)shared_page);
 	write_mr(L4SYS_ARG1, (u32)mode);
 
 	/* Call pager with shmget() request. Check ipc error. */

tasks/libposix/open.c

@@ -3,6 +3,7 @@
  *
  * Copyright (C) 2007 Bahadir Balban
  */
+
 #include <errno.h>
 #include <stdio.h>
 #include <stdarg.h>
@@ -17,13 +18,14 @@
 #include <fcntl.h>
 #include <l4/macros.h>
 #include INC_GLUE(memory.h)
+#include <shpage.h>
 
 static inline int l4_open(const char *pathname, int flags, mode_t mode)
 {
 	int fd;
 
-	copy_to_utcb((void *)pathname, 0, strlen(pathname) + 1);
-	write_mr(L4SYS_ARG0, (unsigned long)utcb_page);
+	copy_to_shpage((void *)pathname, 0, strlen(pathname) + 1);
+	write_mr(L4SYS_ARG0, (unsigned long)shared_page);
 	write_mr(L4SYS_ARG1, flags);
 	write_mr(L4SYS_ARG2, (u32)mode);
 

tasks/libposix/read.c

@@ -3,6 +3,7 @@
  *
  * Copyright (C) 2007 Bahadir Balban
  */
+
 #include <errno.h>
 #include <stdio.h>
 #include <string.h>
@@ -14,14 +15,14 @@
 #include <l4lib/os/posix/readdir.h>
 #include <l4/macros.h>
 #include INC_GLUE(memory.h)
-
+#include <shpage.h>
 
 static inline int l4_readdir(int fd, void *buf, size_t count)
 {
 	int cnt;
 
 	write_mr(L4SYS_ARG0, fd);
-	write_mr(L4SYS_ARG1, (unsigned long)utcb_page);
+	write_mr(L4SYS_ARG1, (unsigned long)shared_page);
 	write_mr(L4SYS_ARG2, count);
 
 	/* Call pager with readdir() request. Check ipc error. */
@@ -36,7 +37,7 @@ static inline int l4_readdir(int fd, void *buf, size_t count)
 
 	}
 
-	copy_from_utcb(buf, 0, cnt);
+	copy_from_shpage(buf, 0, cnt);
 	return cnt;
 }
 

tasks/libposix/shpage.c

@@ -0,0 +1,96 @@
+/*
+ * Initialise posix-related structures.
+ *
+ * Copyright (C) 2007-2009 Bahadir Balban
+ */
+#include <l4lib/kip.h>
+#include <l4lib/arch/syslib.h>
+#include <l4lib/arch/utcb.h>
+#include <l4lib/ipcdefs.h>
+#include <l4/macros.h>
+#include INC_GLUE(memlayout.h)
+#include <stdio.h>
+#include <shpage.h>
+#include <sys/types.h>
+#include <sys/shm.h>
+#include <shpage.h>
+
+/*
+ * Shared page initialisation of posix-like tasks.
+ *
+ * POSIX tasks currently use a default shared page for communciation.
+ * This could have been also done by long ipc calls.
+ */
+
+/*
+ * Shared page for this task. Used for passing data among ipc
+ * parties when message registers are not big enough. Every thread
+ * has right to own one, and it has an address unique to every
+ * thread. It must be explicitly mapped by both parties of the ipc
+ * in order to be useful.
+ */
+void *shared_page;
+
+/*
+ * Obtains a unique address for the task's shared page. Note this
+ * just returns the address. This address is used as an shm key
+ * to map it via shmget()/shmat() later on.
+ */
+static void *shared_page_address(void)
+{
+	void *addr;
+	int err;
+
+	/* We're asking it for ourself. */
+	write_mr(L4SYS_ARG0, self_tid());
+
+	/* Call pager with utcb address request. Check ipc error. */
+	if ((err = l4_sendrecv(PAGER_TID, PAGER_TID,
+			       L4_IPC_TAG_SHPAGE)) < 0) {
+		printf("%s: L4 IPC Error: %d.\n", __FUNCTION__, err);
+		return PTR_ERR(err);
+	}
+
+	/* Check if syscall itself was successful */
+	if (IS_ERR(addr = (void *)l4_get_retval())) {
+		printf("%s: Request UTCB Address Error: %d.\n",
+		       __FUNCTION__, (int)addr);
+		return addr;
+	}
+
+	return addr;
+}
+
+/*
+ * Initialises a non-pager task's default shared memory page
+ * using posix semantics. Used during task initialisation
+ * and by child tasks after a fork.
+ */
+int shared_page_init(void)
+{
+	int shmid;
+	void *shmaddr;
+
+	/*
+	 * Initialise shared page only if we're not the pager.
+	 * The pager does it differently for itself.
+	 */
+	BUG_ON(self_tid() == PAGER_TID);
+
+	/* Obtain our shared page address */
+	shared_page = shared_page_address();
+
+	//printf("%s: UTCB Read from mm0 as: 0x%x\n", __FUNCTION__,
+	//       (unsigned long)shared_page);
+
+	/* Use it as a key to create a shared memory region */
+	BUG_ON((shmid = shmget((key_t)shared_page,
+			       PAGE_SIZE, IPC_CREAT)) < 0);
+
+	/* Attach to the region */
+	BUG_ON((shmaddr = shmat(shmid, shared_page, 0)) < 0);
+	BUG_ON(shmaddr != shared_page);
+
+	return 0;
+}
+

tasks/libposix/stat.c

@@ -18,6 +18,7 @@
 #include <fcntl.h>
 #include <l4/macros.h>
 #include INC_GLUE(memory.h)
+#include <shpage.h>
 
 static inline int l4_fstat(int fd, void *buffer)
 {
@@ -62,10 +63,10 @@ static inline int l4_stat(const char *pathname, void *buffer)
 	int err;
 	struct kstat ks;
 
-	copy_to_utcb((void *)pathname, 0, strlen(pathname) + 1);
+	copy_to_shpage((void *)pathname, 0, strlen(pathname) + 1);
 
 	/* Pathname address on utcb page */
-	write_mr(L4SYS_ARG0, (unsigned long)utcb_page);
+	write_mr(L4SYS_ARG0, (unsigned long)shared_page);
 
 	/* Pass on buffer that should receive stat */
 	write_mr(L4SYS_ARG1, (unsigned long)&ks);