Moved all find_task(sender) calls into topmost ipc handler.

System calls now need not search for the tcb they are serving for.

tasks/mm0/include/file.h

@@ -9,17 +9,15 @@
 void vmfile_init(void);
 
 struct vm_file *vmfile_alloc_init(void);
-int vfs_receive_sys_open(l4id_t sender, l4id_t opener, int fd,
-			 unsigned long vnum, unsigned long size);
 int vfs_read(unsigned long vnum, unsigned long f_offset, unsigned long npages,
 	     void *pagebuf);
 int vfs_write(unsigned long vnum, unsigned long f_offset, unsigned long npages,
 	     void *pagebuf);
-int sys_read(l4id_t sender, int fd, void *buf, int count);
-int sys_write(l4id_t sender, int fd, void *buf, int count);
-int sys_lseek(l4id_t sender, int fd, off_t offset, int whence);
-int sys_close(l4id_t sender, int fd);
-int sys_fsync(l4id_t sender, int fd);
+int sys_read(struct tcb *sender, int fd, void *buf, int count);
+int sys_write(struct tcb *sender, int fd, void *buf, int count);
+int sys_lseek(struct tcb *sender, int fd, off_t offset, int whence);
+int sys_close(struct tcb *sender, int fd);
+int sys_fsync(struct tcb *sender, int fd);
 int file_open(struct tcb *opener, int fd);
 
 struct vfs_file_data {

tasks/mm0/include/syscalls.h

@@ -11,6 +11,7 @@
 
 #include <sys/types.h>
 #include <l4lib/types.h>
+#include <task.h>
 
 /* For reading argument data from a system call */
 struct sys_mmap_args {
@@ -22,10 +23,10 @@ struct sys_mmap_args {
 	off_t offset;
 };
 
-void *sys_mmap(l4id_t sender, void *start, size_t length, int prot,
+void *sys_mmap(struct tcb *sender, void *start, size_t length, int prot,
 	       int flags, int fd, off_t offset);
 
-int sys_munmap(l4id_t sender, void *vaddr, unsigned long size);
+int sys_munmap(struct tcb *sender, void *vaddr, unsigned long size);
 
 struct sys_shmat_args {
 	l4id_t shmid;
@@ -33,8 +34,8 @@ struct sys_shmat_args {
 	int shmflg;
 };
 
-void *sys_shmat(l4id_t requester, l4id_t shmid, const void *shmaddr, int shmflg);
-int sys_shmdt(l4id_t requester, const void *shmaddr);
+void *sys_shmat(struct tcb *requester, l4id_t shmid, const void *shmaddr, int shmflg);
+int sys_shmdt(struct tcb *requester, const void *shmaddr);
 
 struct sys_shmget_args {
 	key_t key;
@@ -44,7 +45,7 @@ struct sys_shmget_args {
 
 int sys_shmget(key_t key, int size, int shmflg);
 
-int sys_fork(l4id_t parent);
+int sys_fork(struct tcb *parent);
 
 #endif /* __MM0_SYSARGS_H__ */
 

tasks/mm0/include/task.h

@@ -113,7 +113,7 @@ struct task_data_head {
 
 struct tcb *find_task(int tid);
 void task_add_global(struct tcb *t);
-int send_task_data(l4id_t requester);
+int send_task_data(struct tcb *requester);
 void task_map_prefault_utcb(struct tcb *mapper, struct tcb *owner);
 int task_mmap_regions(struct tcb *task, struct vm_file *file);
 int task_setup_regions(struct vm_file *file, struct tcb *task,

tasks/mm0/include/utcb.h

@@ -8,7 +8,7 @@ int utcb_pool_init(void);
 
 
 /* IPC to send utcb address information to tasks */
-void *task_send_utcb_address(l4id_t sender, l4id_t taskid);
+void *task_send_utcb_address(struct tcb *sender, l4id_t taskid);
 
 /* Prefault an *mmaped* utcb */
 int utcb_prefault(struct tcb *task, unsigned int vmflags);

tasks/mm0/include/vm_area.h

@@ -252,6 +252,6 @@ static inline void task_add_vma(struct tcb *task, struct vm_area *vma)
 }
 
 /* Main page fault entry point */
-int page_fault_handler(l4id_t tid, fault_kdata_t *fkdata);
+int page_fault_handler(struct tcb *faulty_task, fault_kdata_t *fkdata);
 
 #endif /* __VM_AREA_H__ */

tasks/mm0/main.c

@@ -15,6 +15,7 @@
 #include <l4/api/thread.h>
 #include <l4/api/space.h>
 #include <l4/api/ipc.h>
+#include <l4/api/errno.h>
 #include <vm_area.h>
 #include <syscalls.h>
 #include <file.h>
@@ -26,7 +27,8 @@ void handle_requests(void)
 {
 	/* Generic ipc data */
 	u32 mr[MR_UNUSED_TOTAL];
-	l4id_t sender;
+	l4id_t senderid;
+	struct tcb *sender;
 	u32 tag;
 	int ret;
 
@@ -39,7 +41,12 @@ void handle_requests(void)
 
 	/* Syslib conventional ipc data which uses first few mrs. */
 	tag = l4_get_tag();
-	sender = l4_get_sender();
+	senderid = l4_get_sender();
+
+	if (!(sender = find_task(senderid))) {
+		l4_ipc_return(-ESRCH);
+		return;
+	}
 
 	/* Read mrs not used by syslib */
 	for (int i = 0; i < MR_UNUSED_TOTAL; i++)

tasks/mm0/src/clone.c

@@ -49,7 +49,7 @@ int vfs_notify_fork(struct tcb *child, struct tcb *parent)
 }
 
 
-int do_fork(struct tcb *parent)
+int sys_fork(struct tcb *parent)
 {
 	int err;
 	struct tcb *child;
@@ -111,23 +111,11 @@ int do_fork(struct tcb *parent)
 	return child->tid;
 }
 
-int sys_fork(l4id_t sender)
-{
-	struct tcb *parent;
-
-	if (!(parent = find_task(sender)))
-		return -ESRCH;
-
-	return do_fork(parent);
-}
-
-int sys_clone(l4id_t sender, void *child_stack, unsigned int flags)
+int sys_clone(struct tcb *parent, void *child_stack, unsigned int flags)
 {
 	struct task_ids ids;
 	struct vm_file *utcb_shm;
-	struct tcb *parent, *child;
-
-	BUG_ON(!(parent = find_task(sender)));
+	struct tcb *child;
 
 	ids.tid = TASK_ID_INVALID;
 	ids.spid = parent->spid;

tasks/mm0/src/fault.c

@@ -681,19 +681,15 @@ int do_page_fault(struct fault_data *fault)
 	return __do_page_fault(fault);
 }
 
-int page_fault_handler(l4id_t sender, fault_kdata_t *fkdata)
+int page_fault_handler(struct tcb *sender, fault_kdata_t *fkdata)
 {
 	int err;
 	struct fault_data fault = {
 		/* Fault data from kernel */
 		.kdata = fkdata,
+		.task = sender,
 	};
 
-	BUG_ON(sender == 0);
-
-	/* Get pager specific task info */
-	BUG_ON(!(fault.task = find_task(sender)));
-
 	/* Extract fault reason, fault address etc. in generic format */
 	set_generic_fault_params(&fault);
 

tasks/mm0/src/file.c

@@ -403,13 +403,9 @@ int do_close(struct tcb *task, int fd)
 	return 0;
 }
 
-int sys_close(l4id_t sender, int fd)
+int sys_close(struct tcb *task, int fd)
 {
 	int ret;
-	struct tcb *task;
-
-	if (!(task = find_task(sender)))
-		return -ESRCH;
 
 	/* Sync the file and update stats */
 	if ((ret = fsync_common(task, fd)) < 0)
@@ -419,13 +415,8 @@ int sys_close(l4id_t sender, int fd)
 	return do_close(task, fd);
 }
 
-int sys_fsync(l4id_t sender, int fd)
+int sys_fsync(struct tcb *task, int fd)
 {
-	struct tcb *task;
-
-	if (!(task = find_task(sender)))
-		return -ESRCH;
-
 	/* Sync the file and update stats */
 	return fsync_common(task, fd);
 }
@@ -586,17 +577,13 @@ copy:
 	return count - left;
 }
 
-int sys_read(l4id_t sender, int fd, void *buf, int count)
+int sys_read(struct tcb *task, int fd, void *buf, int count)
 {
 	unsigned long pfn_start, pfn_end;
 	unsigned long cursor, byte_offset;
 	struct vm_file *vmfile;
-	struct tcb *task;
 	int ret = 0;
 
-	if (!(task = find_task(sender)))
-		return -ESRCH;
-
 	/* Check fd validity */
 	if (!task->files->fd[fd].vmfile)
 		if ((ret = file_open(task, fd)) < 0)
@@ -658,19 +645,15 @@ int sys_read(l4id_t sender, int fd, void *buf, int count)
  * We find the page buffer is in, and then copy from the *start* of the page
  * rather than buffer's offset in that page.
  */
-int sys_write(l4id_t sender, int fd, void *buf, int count)
+int sys_write(struct tcb *task, int fd, void *buf, int count)
 {
 	unsigned long pfn_wstart, pfn_wend;	/* Write start/end */
 	unsigned long pfn_fstart, pfn_fend;	/* File start/end */
 	unsigned long pfn_nstart, pfn_nend;	/* New pages start/end */
 	unsigned long cursor, byte_offset;
 	struct vm_file *vmfile;
-	struct tcb *task;
 	int ret = 0;
 
-	if (!(task = find_task(sender)))
-		return -ESRCH;
-
 	/* Check fd validity */
 	if (!task->files->fd[fd].vmfile)
 		if ((ret = file_open(task, fd)) < 0)
@@ -766,15 +749,11 @@ int sys_write(l4id_t sender, int fd, void *buf, int count)
 }
 
 /* FIXME: Check for invalid cursor values. Check for total, sometimes negative. */
-int sys_lseek(l4id_t sender, int fd, off_t offset, int whence)
+int sys_lseek(struct tcb *task, int fd, off_t offset, int whence)
 {
-	struct tcb *task;
 	int retval = 0;
 	unsigned long long total, cursor;
 
-	if (!(task = find_task(sender)))
-		return -ESRCH;
-
 	/* Check fd validity */
 	if (!task->files->fd[fd].vmfile)
 		if ((retval = file_open(task, fd)) < 0)

tasks/mm0/src/mmap.c

@@ -582,19 +582,15 @@ void *do_mmap(struct vm_file *mapfile, unsigned long file_offset,
 }
 
 /* mmap system call implementation */
-void *sys_mmap(l4id_t sender, void *start, size_t length, int prot,
+void *sys_mmap(struct tcb *task, void *start, size_t length, int prot,
 	       int flags, int fd, unsigned long pfn)
 {
 	unsigned long npages = __pfn(page_align_up(length));
 	unsigned long base = (unsigned long)start;
 	struct vm_file *file = 0;
 	unsigned int vmflags = 0;
-	struct tcb *task;
 	int err;
 
-	if (!(task = find_task(sender)))
-		return PTR_ERR(-ESRCH);
-
 	/* Check fd validity */
 	if (!(flags & MAP_ANONYMOUS))
 		if (!task->files->fd[fd].vmfile)
@@ -647,7 +643,7 @@ void *sys_mmap(l4id_t sender, void *start, size_t length, int prot,
 }
 
 /* Sets the end of data segment for sender */
-int sys_brk(l4id_t sender, void *ds_end)
+int sys_brk(struct tcb *sender, void *ds_end)
 {
 	return 0;
 }

tasks/mm0/src/shm.c

@@ -119,10 +119,9 @@ static void *do_shmat(struct vm_file *shm_file, void *shm_addr, int shmflg,
 		utcb_prefault(task, VM_READ | VM_WRITE);
 */
 
-void *sys_shmat(l4id_t requester, l4id_t shmid, void *shmaddr, int shmflg)
+void *sys_shmat(struct tcb *task, l4id_t shmid, void *shmaddr, int shmflg)
 {
 	struct vm_file *shm_file, *n;
-	struct tcb *task = find_task(requester);
 
 	list_for_each_entry_safe(shm_file, n, &shm_file_list, list) {
 		if (shm_file_to_desc(shm_file)->shmid == shmid)
@@ -133,34 +132,26 @@ void *sys_shmat(l4id_t requester, l4id_t shmid, void *shmaddr, int shmflg)
 	return PTR_ERR(-EINVAL);
 }
 
-int do_shmdt(struct vm_file *shm, l4id_t tid)
+int do_shmdt(struct tcb *task, struct vm_file *shm)
 {
-	struct tcb *task = find_task(tid);
 	int err;
 
-	if (!task) {
-		printf("%s:%s: Internal error. Cannot find task with tid %d\n",
-		       __TASKNAME__, __FUNCTION__, tid);
-		BUG();
-	}
 	if ((err = do_munmap(shm_file_to_desc(shm)->shm_addr,
-			     shm_file_to_desc(shm)->npages, task)) < 0) {
-		printf("do_munmap: Unmapping shm segment failed with %d.\n",
-		       err);
-		BUG();
-	}
+			     shm_file_to_desc(shm)->npages,
+			     task)) < 0)
+		return err;
 
-	return err;
+	return 0;
 }
 
-int sys_shmdt(l4id_t requester, const void *shmaddr)
+int sys_shmdt(struct tcb *task, const void *shmaddr)
 {
 	struct vm_file *shm_file, *n;
 	int err;
 
 	list_for_each_entry_safe(shm_file, n, &shm_file_list, list) {
 		if (shm_file_to_desc(shm_file)->shm_addr == shmaddr) {
-			if ((err = do_shmdt(shm_file, requester) < 0))
+			if ((err = do_shmdt(task, shm_file) < 0))
 				return err;
 			else
 				break;

tasks/mm0/src/task.c

@@ -436,20 +436,19 @@ void task_map_prefault_utcb(struct tcb *mapper, struct tcb *owner)
  * are running, and their tids, which includes itself. This function
  * provides that information.
  */
-int send_task_data(l4id_t requester)
+int send_task_data(struct tcb *vfs)
 {
 	int li = 0;
-	struct tcb *t, *vfs, *self;
+	struct tcb *t, *self;
 	struct task_data_head *tdata_head;
 
-	if (requester != VFS_TID) {
+	if (vfs->tid != VFS_TID) {
 		printf("%s: Task data requested by %d, which is not "
-		       "FS0 id %d, ignoring.\n", __TASKNAME__, requester,
+		       "FS0 id %d, ignoring.\n", __TASKNAME__, vfs->tid,
 		       VFS_TID);
 		return 0;
 	}
 
-	BUG_ON(!(vfs = find_task(requester)));
 	BUG_ON(!(self = find_task(self_tid())));
 	BUG_ON(!vfs->utcb);
 

tasks/mm0/src/utcb.c

@@ -39,17 +39,13 @@ void *utcb_vaddr_new(void)
  * for its own. The requester then uses this address as a shm key and
  * maps its own utcb via shmget/shmat.
  */
-void *task_send_utcb_address(l4id_t sender, l4id_t taskid)
+void *task_send_utcb_address(struct tcb *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 (sender->tid == taskid) {
+		/* It hasn't got one allocated. */
 		BUG_ON(!task->utcb);
 
 		/* Return it to requester */
@@ -58,7 +54,7 @@ void *task_send_utcb_address(l4id_t sender, l4id_t taskid)
 	/* 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) {
+		if (sender->tid == VFS_TID) {
 			/*
 			 * Return utcb address to requester. Note if there's
 			 * none allocated so far, requester gets 0. We don't