Various changes to incorporate new utcb setup.

Issues with l4_return value not reaching client side
	modified:   libs/c/include/stdio.h
	modified:   src/arch/arm/exception.c
	modified:   src/glue/arm/init.c
	modified:   tasks/fs0/src/task.c
	modified:   tasks/libl4/include/l4lib/arch-arm/utcb.h
	modified:   tasks/libl4/src/arm/syscalls.S
	modified:   tasks/libl4/src/init.c
	deleted:    tasks/libl4/tagfilelist
	modified:   tasks/libposix/open.c
	modified:   tasks/mm0/include/utcb.h
	modified:   tasks/mm0/include/vm_area.h
	modified:   tasks/mm0/main.c
	modified:   tasks/mm0/src/init.c
	modified:   tasks/mm0/src/task.c
	modified:   tasks/mm0/src/utcb.c
	modified:   tasks/mm0/src/vm_object.c

libs/c/include/stdio.h

@@ -161,7 +161,7 @@ int setvbuf(FILE *, char *, int, size_t);
 /* 7.19.6 Format i/o functions */
 int fprintf(FILE *, const char *, ...);
 int fscanf(FILE *, const char *, ...);
-int printf(const char *format, ...); __attribute__((format (printf, 1, 2)));
+int printf(const char *format, ...) __attribute__((format (printf, 1, 2)));
 int scanf(const char *, ...);
 int snprintf(char *, size_t , const char *, ...);
 int sprintf(char *, const char *, ...);

src/arch/arm/exception.c

@@ -8,6 +8,7 @@
 #include <l4/generic/tcb.h>
 #include <l4/lib/printk.h>
 #include <l4/api/ipc.h>
+#include <l4/api/kip.h>
 #include <l4/api/errno.h>
 #include INC_PLAT(printascii.h)
 #include INC_ARCH(exception.h)
@@ -17,7 +18,7 @@
 #include INC_SUBARCH(mm.h)
 
 /* Abort debugging conditions */
-// #define DEBUG_ABORTS
+//#define DEBUG_ABORTS
 #if defined (DEBUG_ABORTS)
 #define dbg_abort(...)	dprintk(__VA_ARGS__)
 #else
@@ -180,7 +181,15 @@ int check_aborts(u32 faulted_pc, u32 fsr, u32 far)
 void data_abort_handler(u32 faulted_pc, u32 fsr, u32 far)
 {
 	set_abort_type(fsr, ARM_DABT);
+
+	/*
+	 * FIXME: Find why if we use a clause like if tid == PAGER_TID
+	 * this prints just the faulted_pc but not the text "Data abort @ PC:"
+	 * Strange.
+	 */
 	dbg_abort("Data abort @ PC: ", faulted_pc);
+
+	/* Check for more details */
 	if (check_aborts(faulted_pc, fsr, far) < 0) {
 		printascii("This abort can't be handled by any pager.\n");
 		goto error;

src/glue/arm/init.c

@@ -182,10 +182,10 @@ void kip_init()
 
 	kip_init_syscalls();
 
-	/* KIP + 0xFF0 is pointer to UTCB area for this thread group. */
+	/* KIP + 0xFF0 is pointer to UTCB segment start address */
 	utcb_ref = (struct utcb **)((unsigned long)&kip + UTCB_KIP_OFFSET);
 
-	/* All thread groups have their utcb mapped at UTCB_AREA_START */
+	/* All thread utcbs are allocated starting from UTCB_AREA_START */
 	*utcb_ref = (struct utcb *)UTCB_AREA_START;
 
 	add_mapping(virt_to_phys(&kip), USER_KIP_PAGE, PAGE_SIZE,

tasks/fs0/src/task.c

@@ -79,14 +79,11 @@ struct task_data_head {
 	struct task_data tdata[];
 };
 
-/* Read task information into the utcb buffer, since it wont fit into mrs. */
+/* Read task information into the utcb page, since it won't fit into mrs. */
 struct task_data_head *receive_pager_taskdata(void)
 {
 	int err;
 
-	/* Ask pager to write the data at this address */
-	write_mr(L4SYS_ARG0, (unsigned long)utcb->buf);
-
 	/* Make the actual ipc call */
 	if ((err = l4_sendrecv(PAGER_TID, PAGER_TID,
 			       L4_IPC_TAG_TASKDATA)) < 0) {
@@ -100,10 +97,11 @@ struct task_data_head *receive_pager_taskdata(void)
 		return PTR_ERR(err);
 	}
 
+	/* Data is expected in the utcb page */
 	printf("%s: %d Total tasks.\n", __FUNCTION__,
-	       ((struct task_data_head *)utcb->buf)->total);
+	       ((struct task_data_head *)utcb_page)->total);
 
-	return (struct task_data_head *)utcb->buf;
+	return (struct task_data_head *)utcb_page;
 }
 
 /* Allocate a task struct and initialise it */

tasks/libl4/include/l4lib/arch-arm/utcb.h

@@ -23,8 +23,10 @@
 struct utcb {
 	u32 mr[MR_TOTAL];
 	u32 tid;		/* Thread id */
-}; __attribute__((__packed__));
+} __attribute__((__packed__));
+
 extern struct utcb utcb;
+extern void *utcb_page;
 
 static inline struct utcb *l4_get_utcb()
 {

tasks/libl4/src/arm/syscalls.S

@@ -9,7 +9,6 @@
 
 	.macro	utcb_address	rx
 		ldr	\rx, =utcb
-		ldr	\rx, [\rx]
 	.endm
 
 BEGIN_PROC(l4_thread_switch)

tasks/libl4/src/init.c

@@ -1,7 +1,7 @@
 /*
  * Initialise system call offsets.
  *
- * Copyright (C) 2007 Bahadir Balban
+ * Copyright (C) 2007, 2008 Bahadir Balban
  */
 #include <l4lib/kip.h>
 #include <l4lib/arch/syslib.h>
@@ -52,6 +52,9 @@ static void *l4_utcb_page(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_UTCB)) < 0) {
 		printf("%s: L4 IPC Error: %d.\n", __FUNCTION__, err);
@@ -89,7 +92,7 @@ void __l4_init(void)
 	/* Initialise utcb only if we're not the pager */
 	if (self_tid() != PAGER_TID) {
 		utcb_page = l4_utcb_page();
-		printf("UTCB Read from mm0 as: 0x%x\n",
+		printf("%s: UTCB Read from mm0 as: 0x%x\n", __FUNCTION__,
 		(unsigned long)utcb_page);
 	}
 }

tasks/libl4/tagfilelist

@@ -1,20 +0,0 @@
-./src/init.c
-./include/l4lib/kip.h
-./include/l4lib/posix/l4shm.h
-./include/l4lib/arch-arm/asm.h
-./include/l4lib/arch-arm/types.h
-./include/l4lib/arch-arm/utcb.h
-./include/l4lib/arch-arm/syscalls.h
-./include/l4lib/arch-arm/message.h
-./include/l4lib/arch-arm/vregs.h
-./include/l4lib/types.h
-./include/l4lib/ipcdefs.h
-./include/l4lib/utcb.h
-./include/l4lib/examples/ipc.h
-./include/l4lib/examples/message_stuff.h
-./include/l4lib/examples/space.h
-./include/l4lib/examples/thread.h
-./include/l4lib/examples/syscalls.h
-./include/l4lib/examples/message.h
-./include/l4lib/examples/schedule.h
-./src/arm/syscalls.S

tasks/libposix/open.c

@@ -13,6 +13,7 @@
 #include <l4lib/arch/syscalls.h>
 #include <l4lib/arch/syslib.h>
 #include <l4lib/ipcdefs.h>
+#include <l4lib/utcb.h>
 #include <fcntl.h>
 #include <l4/macros.h>
 #include INC_GLUE(memory.h)
@@ -25,7 +26,7 @@
 void *copy_to_utcb(void *arg, int size)
 {
 	BUG_ON(size > PAGE_SIZE);
-	memcpy(utcb->buf, arg, size);
+	memcpy(utcb_page, arg, size);
 }
 
 static inline int l4_open(const char *pathname, int flags, mode_t mode)

tasks/mm0/include/utcb.h

@@ -1,7 +1,12 @@
 #ifndef __MM0_UTCB_H__
 #define __MM0_UTCB_H__
 
+#include <l4lib/types.h>
 void *utcb_vaddr_new(void);
 int utcb_pool_init(void);
 
+
+/* IPC to send utcb address information to tasks */
+int task_send_utcb_address(l4id_t sender, l4id_t taskid);
+
 #endif

tasks/mm0/include/vm_area.h

@@ -14,7 +14,7 @@
 #include <arch/mm.h>
 #include <lib/spinlock.h>
 
-// #define DEBUG_FAULT_HANDLING
+//#define DEBUG_FAULT_HANDLING
 #ifdef DEBUG_FAULT_HANDLING
 #define dprintf(...)	printf(__VA_ARGS__)
 #else

tasks/mm0/main.c

@@ -18,7 +18,7 @@
 #include <syscalls.h>
 #include <file.h>
 #include <shm.h>
-#include <task.h>
+#include <utcb.h>
 
 void handle_requests(void)
 {
@@ -84,6 +84,10 @@ void handle_requests(void)
 				     (unsigned long)mr[2], (unsigned long)mr[3]);
 		break;
 
+	case L4_IPC_TAG_UTCB:
+		task_send_utcb_address(sender, (l4id_t)mr[0]);
+		break;
+
 	case L4_IPC_TAG_READ:
 		sys_read(sender, (int)mr[0], (void *)mr[1], (int)mr[2]);
 		break;

tasks/mm0/src/init.c

@@ -20,21 +20,22 @@
 /*
  * Initialise the utcb virtual address pool and its own utcb.
  * NOTE: This allocates memory so kmalloc must be initialised first.
+ * FIXME: Is this necessary anymore??? Who maps mm0's page to share?
  */
-void init_utcb(void)
+void init_utcb_page(void)
 {
-	void *utcb_virt, *utcb_page;
+	void *utcb_virt, *utcb_phys;
 
 	/* Allocate and map one for self */
 	if (utcb_pool_init() < 0)
 		printf("UTCB initialisation failed.\n");
 	utcb_virt = utcb_vaddr_new();
 	printf("%s: Mapping 0x%x as utcb to self.\n", __TASKNAME__, utcb_virt);
-	utcb_page = alloc_page(1);
+	utcb_phys = alloc_page(1);
-	l4_map(utcb_page, utcb_virt, 1, MAP_USR_RW_FLAGS, self_tid());
+	l4_map(utcb_phys, utcb_virt, 1, MAP_USR_RW_FLAGS, self_tid());
 
-	/* Also initialise the utcb reference that is inside l4lib. */
+	/* Initialise the utcb page that is inside l4lib. */
-	utcb = utcb_virt;
+	utcb_page = utcb_virt;
 }
 
 void init_mm(struct initdata *initdata)
@@ -62,8 +63,8 @@ void init_mm(struct initdata *initdata)
 	shm_init();
 	printf("%s: Initialised shm structures.\n", __TASKNAME__);
 
-	init_utcb();
+	init_utcb_page();
-	printf("%s: Initialised own utcb.\n", __TASKNAME__);
+	printf("%s: Initialised mm0 utcb page.\n", __TASKNAME__);
 
 	/* Give the kernel some memory to use for its allocators */
 	l4_kmem_grant(__pfn(alloc_page(__pfn(SZ_1MB))), __pfn(SZ_1MB));

tasks/mm0/src/task.c

@@ -218,9 +218,6 @@ int start_boot_task(struct vm_file *file, struct task_ids *ids)
 	task->tid = ids->tid;
 	task->spid = ids->spid;
 
-	/* Allocate a utcb virtual address */
-	task->utcb_address = (unsigned long)utcb_vaddr_new();
-
 	/* Prepare environment boundaries. */
 	task->env_end = USER_AREA_END;
 	task->env_start = task->env_end - DEFAULT_ENV_SIZE;
@@ -280,16 +277,6 @@ int start_boot_task(struct vm_file *file, struct task_ids *ids)
 		goto error;
 	}
 
-	/* mmap each task's utcb as single page anonymous memory. */
-	printf("%s: Mapping utcb for new task at: 0x%x\n", __TASKNAME__,
-	       task->utcb_address);
-	if ((err = do_mmap(0, 0, task, task->utcb_address,
-			   VM_READ | VM_WRITE | VMA_SHARED | VMA_ANONYMOUS,
-			   __pfn(DEFAULT_UTCB_SIZE))) < 0) {
-		printf("do_mmap: Mapping utcb failed with %d.\n", err);
-		goto error;
-	}
-
 	/* Add the task to the global task list */
 	list_add(&task->list, &tcb_head.list);
 	tcb_head.total++;
@@ -440,7 +427,6 @@ void send_task_data(l4id_t requester)
 {
 	int li, err;
 	struct tcb *t, *vfs;
-	struct utcb *vfs_utcb;
 	struct task_data_head *tdata_head;
 
 	if (requester != VFS_TID) {
@@ -451,16 +437,14 @@ void send_task_data(l4id_t requester)
 	}
 
 	BUG_ON(!(vfs = find_task(requester)));
+	BUG_ON(!vfs->utcb_address);
 
 	/* Map in vfs's utcb. FIXME: Whatif it is already mapped? */
 	l4_map((void *)page_to_phys(task_virt_to_page(vfs, vfs->utcb_address)),
 	       (void *)vfs->utcb_address, 1, MAP_USR_RW_FLAGS, self_tid());
 
-	/* Get a handle on vfs utcb */
-	vfs_utcb = (struct utcb *)vfs->utcb_address;
-
 	/* Write all requested task information to utcb's user buffer area */
-	tdata_head = (struct task_data_head *)vfs_utcb->buf;
+	tdata_head = (struct task_data_head *)vfs->utcb_address;
 
 	/* First word is total number of tcbs */
 	tdata_head->total = tcb_head.total;

tasks/mm0/src/utcb.c

@@ -8,6 +8,9 @@
 #include <utcb.h>
 #include <lib/addr.h>
 #include <l4/macros.h>
+#include <l4lib/arch/syscalls.h>
+#include <l4lib/arch/syslib.h>
+#include <task.h>
 #include INC_GLUE(memlayout.h)
 
 static struct address_pool utcb_vaddr_pool;
@@ -29,4 +32,45 @@ void *utcb_vaddr_new(void)
 	return address_new(&utcb_vaddr_pool, 1);
 }
 
+/*
+ * Sends utcb address information to requester task, allocates
+ * an address if it doesn't exist and the requester is asking
+ * for its own.
+ */
+int task_send_utcb_address(l4id_t sender, l4id_t taskid)
+{
+	struct tcb *task = find_task(taskid);
+
+	/* Is the task asking for its own utcb address */
+	if (sender == taskid) {
+		/*
+		 * It hasn't got one allocated. We allocate one here,
+		 * but only because the requester is requesting for its
+		 * own utcb.
+		 */
+		if (!task->utcb_address)
+			task->utcb_address = (unsigned long)utcb_vaddr_new();
+
+		/* Return it to requester */
+		printf("%s: Returning 0x%x\n", __FUNCTION__, task->utcb_address);
+		return l4_ipc_return(task->utcb_address);
+
+	/* A task is asking for someone else's utcb */
+	} else {
+		/* Only vfs is allowed to do so yet, because its a server */
+		if (sender == VFS_TID) {
+			/*
+			 * Return utcb address to requester. Note if there's
+			 * none allocated so far, requester gets 0. We don't
+			 * allocate one here.
+			 */
+			printf("%s: Returning 0x%x\n", __FUNCTION__,
+			       task->utcb_address);
+			return l4_ipc_return(task->utcb_address);
+		}
+	}
+	return 0;
+}
+
+
 

tasks/mm0/src/vm_object.c

@@ -8,14 +8,6 @@
 #include <l4/api/errno.h>
 #include <kmalloc/kmalloc.h>
 
-
-// #define DEBUG_FAULT_HANDLING
-#ifdef DEBUG_FAULT_HANDLING
-#define dprintf(...)	printf(__VA_ARGS__)
-#else
-#define dprintf(...)
-#endif
-
 #if defined(DEBUG_FAULT_HANDLING)
 void print_cache_pages(struct vm_object *vmo)
 {