diff options
Diffstat (limited to 'pkg/sentry/fs/ramfs')
| -rw-r--r-- | pkg/sentry/fs/ramfs/ramfs.go | 52 |
1 files changed, 29 insertions, 23 deletions
diff --git a/pkg/sentry/fs/ramfs/ramfs.go b/pkg/sentry/fs/ramfs/ramfs.go index 04f2d38de..90b6c9a4f 100644 --- a/pkg/sentry/fs/ramfs/ramfs.go +++ b/pkg/sentry/fs/ramfs/ramfs.go @@ -95,8 +95,9 @@ func (e *Entry) InitEntryWithAttr(ctx context.Context, uattr fs.UnstableAttr) { // UnstableAttr implements fs.InodeOperations.UnstableAttr. func (e *Entry) UnstableAttr(ctx context.Context, inode *fs.Inode) (fs.UnstableAttr, error) { e.mu.Lock() - defer e.mu.Unlock() - return e.unstable, nil + attr := e.unstable + e.mu.Unlock() + return attr, nil } // Check implements fs.InodeOperations.Check. @@ -106,9 +107,11 @@ func (*Entry) Check(ctx context.Context, inode *fs.Inode, p fs.PermMask) bool { // Getxattr implements fs.InodeOperations.Getxattr. func (e *Entry) Getxattr(inode *fs.Inode, name string) ([]byte, error) { + // Hot path. Avoid defers. e.mu.Lock() - defer e.mu.Unlock() - if value, ok := e.xattrs[name]; ok { + value, ok := e.xattrs[name] + e.mu.Unlock() + if ok { return value, nil } return nil, syserror.ENOATTR @@ -117,19 +120,19 @@ func (e *Entry) Getxattr(inode *fs.Inode, name string) ([]byte, error) { // Setxattr implements fs.InodeOperations.Setxattr. func (e *Entry) Setxattr(inode *fs.Inode, name string, value []byte) error { e.mu.Lock() - defer e.mu.Unlock() e.xattrs[name] = value + e.mu.Unlock() return nil } // Listxattr implements fs.InodeOperations.Listxattr. func (e *Entry) Listxattr(inode *fs.Inode) (map[string]struct{}, error) { e.mu.Lock() - defer e.mu.Unlock() names := make(map[string]struct{}, len(e.xattrs)) for name := range e.xattrs { names[name] = struct{}{} } + e.mu.Unlock() return names, nil } @@ -141,22 +144,22 @@ func (*Entry) GetFile(ctx context.Context, d *fs.Dirent, flags fs.FileFlags) (*f // SetPermissions always sets the permissions. func (e *Entry) SetPermissions(ctx context.Context, inode *fs.Inode, p fs.FilePermissions) bool { e.mu.Lock() - defer e.mu.Unlock() e.unstable.Perms = p e.unstable.StatusChangeTime = ktime.NowFromContext(ctx) + e.mu.Unlock() return true } // SetOwner always sets ownership. func (e *Entry) SetOwner(ctx context.Context, inode *fs.Inode, owner fs.FileOwner) error { e.mu.Lock() - defer e.mu.Unlock() if owner.UID.Ok() { e.unstable.Owner.UID = owner.UID } if owner.GID.Ok() { e.unstable.Owner.GID = owner.GID } + e.mu.Unlock() return nil } @@ -167,8 +170,6 @@ func (e *Entry) SetTimestamps(ctx context.Context, inode *fs.Inode, ts fs.TimeSp } e.mu.Lock() - defer e.mu.Unlock() - now := ktime.NowFromContext(ctx) if !ts.ATimeOmit { if ts.ATimeSetSystemTime { @@ -185,59 +186,64 @@ func (e *Entry) SetTimestamps(ctx context.Context, inode *fs.Inode, ts fs.TimeSp } } e.unstable.StatusChangeTime = now + e.mu.Unlock() return nil } // NotifyStatusChange updates the status change time (ctime). func (e *Entry) NotifyStatusChange(ctx context.Context) { e.mu.Lock() - defer e.mu.Unlock() e.unstable.StatusChangeTime = ktime.NowFromContext(ctx) + e.mu.Unlock() } // StatusChangeTime returns the last status change time for this node. func (e *Entry) StatusChangeTime() ktime.Time { e.mu.Lock() - defer e.mu.Unlock() - return e.unstable.StatusChangeTime + t := e.unstable.StatusChangeTime + e.mu.Unlock() + return t } // NotifyModification updates the modification time and the status change time. func (e *Entry) NotifyModification(ctx context.Context) { e.mu.Lock() - defer e.mu.Unlock() now := ktime.NowFromContext(ctx) e.unstable.ModificationTime = now e.unstable.StatusChangeTime = now + e.mu.Unlock() } // ModificationTime returns the last modification time for this node. func (e *Entry) ModificationTime() ktime.Time { e.mu.Lock() - defer e.mu.Unlock() - return e.unstable.ModificationTime + t := e.unstable.ModificationTime + e.mu.Unlock() + return t } // NotifyAccess updates the access time. func (e *Entry) NotifyAccess(ctx context.Context) { e.mu.Lock() - defer e.mu.Unlock() now := ktime.NowFromContext(ctx) e.unstable.AccessTime = now + e.mu.Unlock() } // AccessTime returns the last access time for this node. func (e *Entry) AccessTime() ktime.Time { e.mu.Lock() - defer e.mu.Unlock() - return e.unstable.AccessTime + t := e.unstable.AccessTime + e.mu.Unlock() + return t } // Permissions returns permissions on this entry. func (e *Entry) Permissions() fs.FilePermissions { e.mu.Lock() - defer e.mu.Unlock() - return e.unstable.Perms + p := e.unstable.Perms + e.mu.Unlock() + return p } // Lookup is not supported by default. @@ -379,15 +385,15 @@ func (e *Entry) Release(context.Context) {} // AddLink implements InodeOperationss.AddLink. func (e *Entry) AddLink() { e.mu.Lock() - defer e.mu.Unlock() e.unstable.Links++ + e.mu.Unlock() } // DropLink implements InodeOperationss.DropLink. func (e *Entry) DropLink() { e.mu.Lock() - defer e.mu.Unlock() e.unstable.Links-- + e.mu.Unlock() } // DeprecatedReaddir is not supported by default. |