From 0557fa8910b00024261695b3433169384bc2a687 Mon Sep 17 00:00:00 2001
From: Bahadir Balban <bbalban@b-labs.co.uk>
Date: Sat, 26 Apr 2008 01:03:11 +0100
Subject: [PATCH] Gotta find a way to pass on updated file size before
 write_file_pages.

---
 tasks/fs0/src/memfs/vnode.c |  3 +-
 tasks/fs0/src/syscalls.c    | 63 ++++++++++++++++++++++++++-----------
 tasks/mm0/src/file.c        | 15 +++++----
 3 files changed, 56 insertions(+), 25 deletions(-)

diff --git a/tasks/fs0/src/memfs/vnode.c b/tasks/fs0/src/memfs/vnode.c
index db3d373..61220a0 100644
--- a/tasks/fs0/src/memfs/vnode.c
+++ b/tasks/fs0/src/memfs/vnode.c
@@ -260,7 +260,8 @@ struct vnode *memfs_vnode_mknod(struct vnode *v, const char *dirname,
 	memfsd->name[MEMFS_DNAME_MAX - 1] = '\0';
 
 	/* Write the updated directory buffer back to disk block */
-	v->fops.write(v, 0, 1, v->dirbuf.buffer);
+	if ((err = v->fops.write(v, 0, 1, v->dirbuf.buffer)) < 0)
+		return PTR_ERR(err); /* FIXME: free all you allocated so far */
 
 	/* Update parent vnode size */
 	v->size += sizeof(*memfsd);
diff --git a/tasks/fs0/src/syscalls.c b/tasks/fs0/src/syscalls.c
index ff58694..f63d595 100644
--- a/tasks/fs0/src/syscalls.c
+++ b/tasks/fs0/src/syscalls.c
@@ -230,22 +230,32 @@ int pager_sys_read(l4id_t sender, unsigned long vnum, unsigned long f_offset,
 		   unsigned long npages, void *pagebuf)
 {
 	struct vnode *v;
-	int err;
+	int err, retval = 0;
 
-	if (sender != PAGER_TID)
-		return -EINVAL;
+	if (sender != PAGER_TID) {
+		retval = -EINVAL;
+		goto out;
+	}
 
 	/* Lookup vnode */
-	if (!(v = vfs_lookup_byvnum(vfs_root.pivot->sb, vnum)))
-		return -EINVAL; /* No such vnode */
+	if (!(v = vfs_lookup_byvnum(vfs_root.pivot->sb, vnum))) {
+		retval = -EINVAL; /* No such vnode */
+		goto out;
+	}
 
 	/* Ensure vnode is not a directory */
-	if (vfs_isdir(v))
-		return -EISDIR;
+	if (vfs_isdir(v)) {
+		retval = -EISDIR;
+		goto out;
+	}
 
-	if ((err = v->fops.read(v, f_offset, npages, pagebuf)) < 0)
-		return err;
+	if ((err = v->fops.read(v, f_offset, npages, pagebuf)) < 0) {
+		retval = err;
+		goto out;
+	}
 
+out:
+	l4_ipc_return(retval);
 	return 0;
 }
 
@@ -260,22 +270,39 @@ int pager_sys_write(l4id_t sender, unsigned long vnum, unsigned long f_offset,
 		    unsigned long npages, void *pagebuf)
 {
 	struct vnode *v;
-	int err;
+	int err, retval = 0;
+	int bytes = 0;
 
-	if (sender != PAGER_TID)
-		return -EINVAL;
+	if (sender != PAGER_TID) {
+		retval = -EINVAL;
+		goto out;
+	}
 
 	/* Lookup vnode */
-	if (!(v = vfs_lookup_byvnum(vfs_root.pivot->sb, vnum)))
-		return -EINVAL; /* No such vnode */
+	if (!(v = vfs_lookup_byvnum(vfs_root.pivot->sb, vnum))) {
+		retval = -EINVAL; /* No such vnode */
+		goto out;
+	}
 
 	/* Ensure vnode is not a directory */
-	if (vfs_isdir(v))
-		return -EISDIR;
+	if (vfs_isdir(v)) {
+		retval = -EISDIR;
+		goto out;
+	}
 
-	if ((err = v->fops.write(v, f_offset, npages, pagebuf)) < 0)
-		return err;
+	/* If the file is extended, write automatically extends it */
+	if ((err = v->fops.write(v, f_offset, npages, pagebuf)) < 0) {
+		retval = err;
+		goto out;
+	}
 
+	/* FIXME: Find a way to properly update new bytes */
+	BUG();
+	v->size += bytes;
+	v->sb->ops->write_vnode(v->sb, v);
+
+out:
+	l4_ipc_return(retval);
 	return 0;
 }
 
diff --git a/tasks/mm0/src/file.c b/tasks/mm0/src/file.c
index 4923f88..6a197e6 100644
--- a/tasks/mm0/src/file.c
+++ b/tasks/mm0/src/file.c
@@ -238,18 +238,18 @@ int vfs_write(unsigned long vnum, unsigned long file_offset,
 }
 
 /* Writes pages in cache back to their file */
-int write_file_pages(struct vm_file *vmfile, unsigned long pfn_start,
+int write_file_pages(struct vm_file *f, unsigned long pfn_start,
 		     unsigned long pfn_end)
 {
 	int err;
 
+	BUG_ON(pfn_end != __pfn(page_align_up(f->length)));
 	for (int f_offset = pfn_start; f_offset < pfn_end; f_offset++) {
-		err = vmfile->vm_obj.pager->ops.page_out(&vmfile->vm_obj,
-							 f_offset);
+		err = f->vm_obj.pager->ops.page_out(&f->vm_obj, f_offset);
 		if (err < 0) {
 			printf("%s: %s:Could not write page %d "
 			       "to file with vnum: 0x%x\n", __TASKNAME__,
-			       __FUNCTION__, f_offset, vm_file_to_vnum(vmfile));
+			       __FUNCTION__, f_offset, vm_file_to_vnum(f));
 			return err;
 		}
 	}
@@ -257,9 +257,11 @@ int write_file_pages(struct vm_file *vmfile, unsigned long pfn_start,
 	return 0;
 }
 
-int flush_file_pages(struct vm_file *vmfile)
+int flush_file_pages(struct vm_file *f)
 {
+	write_file_pages(f, 0, __pfn(page_align_up(f->length)));
 
+	return 0;
 }
 
 int sys_close(l4id_t sender, int fd)
@@ -289,8 +291,9 @@ out:
 	return 0;
 }
 
-int sys_flush(void)
+int sys_fsync(int fd)
 {
+	return 0;
 }
 
 /* FIXME: Add error handling to this */