diff options
Diffstat (limited to 'pkg/sentry/fs/tmpfs/fs.go')
-rw-r--r-- | pkg/sentry/fs/tmpfs/fs.go | 38 |
1 files changed, 30 insertions, 8 deletions
diff --git a/pkg/sentry/fs/tmpfs/fs.go b/pkg/sentry/fs/tmpfs/fs.go index b7c29a4d1..be98ad751 100644 --- a/pkg/sentry/fs/tmpfs/fs.go +++ b/pkg/sentry/fs/tmpfs/fs.go @@ -18,10 +18,10 @@ import ( "fmt" "strconv" - "gvisor.googlesource.com/gvisor/pkg/abi/linux" - "gvisor.googlesource.com/gvisor/pkg/sentry/context" - "gvisor.googlesource.com/gvisor/pkg/sentry/fs" - "gvisor.googlesource.com/gvisor/pkg/sentry/kernel/auth" + "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/sentry/fs" + "gvisor.dev/gvisor/pkg/sentry/kernel/auth" ) const ( @@ -34,6 +34,16 @@ const ( // GID for the root directory. rootGIDKey = "gid" + // cacheKey sets the caching policy for the mount. + cacheKey = "cache" + + // cacheAll uses the virtual file system cache for everything (default). + cacheAll = "cache" + + // cacheRevalidate allows dirents to be cached, but revalidates them on each + // lookup. + cacheRevalidate = "revalidate" + // TODO(edahlgren/mpratt): support a tmpfs size limit. // size = "size" @@ -55,7 +65,7 @@ func init() { fs.RegisterFilesystem(&Filesystem{}) } -// FilesystemName is the name underwhich the filesystem is registered. +// FilesystemName is the name under which the filesystem is registered. // Name matches mm/shmem.c:shmem_fs_type.name. const FilesystemName = "tmpfs" @@ -122,15 +132,27 @@ func (f *Filesystem) Mount(ctx context.Context, device string, flags fs.MountSou delete(options, rootGIDKey) } + // Construct a mount which will follow the cache options provided. + // + // TODO(gvisor.dev/issue/179): There should be no reason to disable + // caching once bind mounts are properly supported. + var msrc *fs.MountSource + switch options[cacheKey] { + case "", cacheAll: + msrc = fs.NewCachingMountSource(ctx, f, flags) + case cacheRevalidate: + msrc = fs.NewRevalidatingMountSource(ctx, f, flags) + default: + return nil, fmt.Errorf("invalid cache policy option %q", options[cacheKey]) + } + delete(options, cacheKey) + // Fail if the caller passed us more options than we can parse. They may be // expecting us to set something we can't set. if len(options) > 0 { return nil, fmt.Errorf("unsupported mount options: %v", options) } - // Construct a mount which will cache dirents. - msrc := fs.NewCachingMountSource(f, flags) - // Construct the tmpfs root. return NewDir(ctx, nil, owner, perms, msrc), nil } |