// LOCKS_EXCLUDED(fs.mu)
func (fs *fileSystem) OpenFile(
ctx context.Context,
op *fuseops.OpenFileOp) (err error) {
fs.mu.Lock()
defer fs.mu.Unlock()
// Find the inode.
in := fs.inodes[op.Inode].(*inode.FileInode)
// Allocate a handle.
handleID := fs.nextHandleID
fs.nextHandleID++
fs.handles[handleID] = handle.NewFileHandle(in, fs.bucket)
op.Handle = handleID
// When we observe object generations that we didn't create, we assign them
// new inode IDs. So for a given inode, all modifications go through the
// kernel. Therefore it's safe to tell the kernel to keep the page cache from
// open to open for a given inode.
op.KeepPageCache = true
return
}
// LOCKS_EXCLUDED(fs.mu)
func (fs *fileSystem) CreateFile(
ctx context.Context,
op *fuseops.CreateFileOp) (err error) {
// Create the child.
child, err := fs.createFile(ctx, op.Parent, op.Name, op.Mode)
if err != nil {
return
}
defer fs.unlockAndMaybeDisposeOfInode(child, &err)
// Allocate a handle.
fs.mu.Lock()
handleID := fs.nextHandleID
fs.nextHandleID++
fs.handles[handleID] = handle.NewFileHandle(
child.(*inode.FileInode),
fs.bucket)
op.Handle = handleID
fs.mu.Unlock()
// Fill out the response.
e := &op.Entry
e.Child = child.ID()
e.Attributes, e.AttributesExpiration, err = fs.getAttributes(ctx, child)
if err != nil {
err = fmt.Errorf("getAttributes: %v", err)
return
}
return
}
// LOCKS_EXCLUDED(fs.mu)
func (fs *fileSystem) CreateFile(
ctx context.Context,
op *fuseops.CreateFileOp) (err error) {
// Find the parent.
fs.mu.Lock()
parent := fs.inodes[op.Parent].(inode.DirInode)
fs.mu.Unlock()
// Create an empty backing object for the child, failing if it already
// exists.
parent.Lock()
o, err := parent.CreateChildFile(ctx, op.Name)
parent.Unlock()
// Special case: *gcs.PreconditionError means the name already exists.
if _, ok := err.(*gcs.PreconditionError); ok {
err = fuse.EEXIST
return
}
// Propagate other errors.
if err != nil {
err = fmt.Errorf("CreateChildFile: %v", err)
return
}
// Attempt to create a child inode using the object we created. If we fail to
// do so, it means someone beat us to the punch with a newer generation
// (unlikely, so we're probably okay with failing here).
fs.mu.Lock()
child := fs.lookUpOrCreateInodeIfNotStale(o.Name, o)
if child == nil {
err = fmt.Errorf("Newly-created record is already stale")
return
}
defer fs.unlockAndMaybeDisposeOfInode(child, &err)
// Allocate a handle.
fs.mu.Lock()
handleID := fs.nextHandleID
fs.nextHandleID++
fs.handles[handleID] = handle.NewFileHandle(
child.(*inode.FileInode),
fs.bucket)
op.Handle = handleID
fs.mu.Unlock()
// Fill out the response.
e := &op.Entry
e.Child = child.ID()
e.Attributes, e.AttributesExpiration, err = fs.getAttributes(ctx, child)
if err != nil {
err = fmt.Errorf("getAttributes: %v", err)
return
}
return
}