diff options
Diffstat (limited to 'pkg/sentry/vfs/mount.go')
| -rw-r--r-- | pkg/sentry/vfs/mount.go | 56 |
1 files changed, 29 insertions, 27 deletions
diff --git a/pkg/sentry/vfs/mount.go b/pkg/sentry/vfs/mount.go index 198fb8067..1c3b2e987 100644 --- a/pkg/sentry/vfs/mount.go +++ b/pkg/sentry/vfs/mount.go @@ -110,12 +110,12 @@ type MountNamespace struct { // NewMountNamespace returns a new mount namespace with a root filesystem // configured by the given arguments. A reference is taken on the returned // MountNamespace. -func (vfs *VirtualFilesystem) NewMountNamespace(ctx context.Context, creds *auth.Credentials, source, fsTypeName string, opts *NewFilesystemOptions) (*MountNamespace, error) { +func (vfs *VirtualFilesystem) NewMountNamespace(ctx context.Context, creds *auth.Credentials, source, fsTypeName string, opts *GetFilesystemOptions) (*MountNamespace, error) { fsType := vfs.getFilesystemType(fsTypeName) if fsType == nil { return nil, syserror.ENODEV } - fs, root, err := fsType.NewFilesystem(ctx, creds, source, *opts) + fs, root, err := fsType.GetFilesystem(ctx, vfs, creds, source, *opts) if err != nil { return nil, err } @@ -133,13 +133,13 @@ func (vfs *VirtualFilesystem) NewMountNamespace(ctx context.Context, creds *auth return mntns, nil } -// NewMount creates and mounts a new Filesystem. -func (vfs *VirtualFilesystem) NewMount(ctx context.Context, creds *auth.Credentials, source string, target *PathOperation, fsTypeName string, opts *NewFilesystemOptions) error { +// NewMount creates and mounts a Filesystem configured by the given arguments. +func (vfs *VirtualFilesystem) NewMount(ctx context.Context, creds *auth.Credentials, source string, target *PathOperation, fsTypeName string, opts *GetFilesystemOptions) error { fsType := vfs.getFilesystemType(fsTypeName) if fsType == nil { return syserror.ENODEV } - fs, root, err := fsType.NewFilesystem(ctx, creds, source, *opts) + fs, root, err := fsType.GetFilesystem(ctx, vfs, creds, source, *opts) if err != nil { return err } @@ -147,8 +147,8 @@ func (vfs *VirtualFilesystem) NewMount(ctx context.Context, creds *auth.Credenti // lock ordering. vd, err := vfs.GetDentryAt(ctx, creds, target, &GetDentryOptions{}) if err != nil { - root.decRef(fs) - fs.decRef() + root.DecRef() + fs.DecRef() return err } vfs.mountMu.Lock() @@ -158,8 +158,8 @@ func (vfs *VirtualFilesystem) NewMount(ctx context.Context, creds *auth.Credenti vd.dentry.mu.Unlock() vfs.mountMu.Unlock() vd.DecRef() - root.decRef(fs) - fs.decRef() + root.DecRef() + fs.DecRef() return syserror.ENOENT } // vd might have been mounted over between vfs.GetDentryAt() and @@ -179,7 +179,7 @@ func (vfs *VirtualFilesystem) NewMount(ctx context.Context, creds *auth.Credenti break } // This can't fail since we're holding vfs.mountMu. - nextmnt.root.incRef(nextmnt.fs) + nextmnt.root.IncRef() vd.dentry.mu.Unlock() vd.DecRef() vd = VirtualDentry{ @@ -229,7 +229,7 @@ type umountRecursiveOptions struct { // Mounts on which references must be dropped to vdsToDecRef and mountsToDecRef // respectively, and returns updated slices. (This is necessary because // filesystem locks possibly taken by DentryImpl.DecRef() may precede -// vfs.mountMu in the lock order, and Mount.decRef() may lock vfs.mountMu.) +// vfs.mountMu in the lock order, and Mount.DecRef() may lock vfs.mountMu.) // // umountRecursiveLocked is analogous to Linux's fs/namespace.c:umount_tree(). // @@ -322,13 +322,15 @@ func (mnt *Mount) tryIncMountedRef() bool { } } -func (mnt *Mount) incRef() { +// IncRef increments mnt's reference count. +func (mnt *Mount) IncRef() { // In general, negative values for mnt.refs are valid because the MSB is // the eager-unmount bit. atomic.AddInt64(&mnt.refs, 1) } -func (mnt *Mount) decRef() { +// DecRef decrements mnt's reference count. +func (mnt *Mount) DecRef() { refs := atomic.AddInt64(&mnt.refs, -1) if refs&^math.MinInt64 == 0 { // mask out MSB var vd VirtualDentry @@ -339,8 +341,8 @@ func (mnt *Mount) decRef() { mnt.vfs.mounts.seq.EndWrite() mnt.vfs.mountMu.Unlock() } - mnt.root.decRef(mnt.fs) - mnt.fs.decRef() + mnt.root.DecRef() + mnt.fs.DecRef() if vd.Ok() { vd.DecRef() } @@ -368,7 +370,7 @@ func (mntns *MountNamespace) DecRef(vfs *VirtualFilesystem) { vd.DecRef() } for _, mnt := range mountsToDecRef { - mnt.decRef() + mnt.DecRef() } } else if refs < 0 { panic("MountNamespace.DecRef() called without holding a reference") @@ -413,7 +415,7 @@ retryFirst: // Raced with umount. continue } - mnt.decRef() + mnt.DecRef() mnt = next d = next.root } @@ -447,15 +449,15 @@ retryFirst: // Raced with umount. goto retryFirst } - if !point.tryIncRef(parent.fs) { + if !point.TryIncRef() { // Since Mount holds a reference on Mount.key.point, this can only // happen due to a racing change to Mount.key. - parent.decRef() + parent.DecRef() goto retryFirst } if !vfs.mounts.seq.ReadOk(epoch) { - point.decRef(parent.fs) - parent.decRef() + point.DecRef() + parent.DecRef() goto retryFirst } mnt = parent @@ -480,19 +482,19 @@ retryFirst: // Raced with umount. goto retryNotFirst } - if !point.tryIncRef(parent.fs) { + if !point.TryIncRef() { // Since Mount holds a reference on Mount.key.point, this can // only happen due to a racing change to Mount.key. - parent.decRef() + parent.DecRef() goto retryNotFirst } if !vfs.mounts.seq.ReadOk(epoch) { - point.decRef(parent.fs) - parent.decRef() + point.DecRef() + parent.DecRef() goto retryNotFirst } - d.decRef(mnt.fs) - mnt.decRef() + d.DecRef() + mnt.DecRef() mnt = parent d = point } |