diff options
Diffstat (limited to 'pkg/sentry/memmap')
| -rw-r--r-- | pkg/sentry/memmap/BUILD | 27 | ||||
| -rw-r--r-- | pkg/sentry/memmap/mapping_set.go | 2 | ||||
| -rw-r--r-- | pkg/sentry/memmap/mapping_set_test.go | 2 | ||||
| -rw-r--r-- | pkg/sentry/memmap/memmap.go | 79 |
4 files changed, 87 insertions, 23 deletions
diff --git a/pkg/sentry/memmap/BUILD b/pkg/sentry/memmap/BUILD index 3ef84245b..2c95669cd 100644 --- a/pkg/sentry/memmap/BUILD +++ b/pkg/sentry/memmap/BUILD @@ -1,6 +1,5 @@ -load("@io_bazel_rules_go//go:def.bzl", "go_test") +load("//tools:defs.bzl", "go_library", "go_test") load("//tools/go_generics:defs.bzl", "go_template_instance") -load("//tools/go_stateify:defs.bzl", "go_library") package(licenses = ["notice"]) @@ -29,23 +28,33 @@ go_template_instance( }, ) +go_template_instance( + name = "file_range", + out = "file_range.go", + package = "memmap", + prefix = "File", + template = "//pkg/segment:generic_range", + types = { + "T": "uint64", + }, +) + go_library( name = "memmap", srcs = [ + "file_range.go", "mappable_range.go", "mapping_set.go", "mapping_set_impl.go", "memmap.go", ], - importpath = "gvisor.dev/gvisor/pkg/sentry/memmap", visibility = ["//pkg/sentry:internal"], deps = [ + "//pkg/context", "//pkg/log", - "//pkg/refs", - "//pkg/sentry/context", - "//pkg/sentry/platform", - "//pkg/sentry/usermem", + "//pkg/safemem", "//pkg/syserror", + "//pkg/usermem", ], ) @@ -53,6 +62,6 @@ go_test( name = "memmap_test", size = "small", srcs = ["mapping_set_test.go"], - embed = [":memmap"], - deps = ["//pkg/sentry/usermem"], + library = ":memmap", + deps = ["//pkg/usermem"], ) diff --git a/pkg/sentry/memmap/mapping_set.go b/pkg/sentry/memmap/mapping_set.go index 0a5b7ce45..d609c1ae0 100644 --- a/pkg/sentry/memmap/mapping_set.go +++ b/pkg/sentry/memmap/mapping_set.go @@ -18,7 +18,7 @@ import ( "fmt" "math" - "gvisor.dev/gvisor/pkg/sentry/usermem" + "gvisor.dev/gvisor/pkg/usermem" ) // MappingSet maps offsets into a Mappable to mappings of those offsets. It is diff --git a/pkg/sentry/memmap/mapping_set_test.go b/pkg/sentry/memmap/mapping_set_test.go index f9b11a59c..d39efe38f 100644 --- a/pkg/sentry/memmap/mapping_set_test.go +++ b/pkg/sentry/memmap/mapping_set_test.go @@ -18,7 +18,7 @@ import ( "reflect" "testing" - "gvisor.dev/gvisor/pkg/sentry/usermem" + "gvisor.dev/gvisor/pkg/usermem" ) type testMappingSpace struct { diff --git a/pkg/sentry/memmap/memmap.go b/pkg/sentry/memmap/memmap.go index 03b99aaea..65d83096f 100644 --- a/pkg/sentry/memmap/memmap.go +++ b/pkg/sentry/memmap/memmap.go @@ -18,14 +18,13 @@ package memmap import ( "fmt" - "gvisor.dev/gvisor/pkg/refs" - "gvisor.dev/gvisor/pkg/sentry/context" - "gvisor.dev/gvisor/pkg/sentry/platform" - "gvisor.dev/gvisor/pkg/sentry/usermem" + "gvisor.dev/gvisor/pkg/context" + "gvisor.dev/gvisor/pkg/safemem" + "gvisor.dev/gvisor/pkg/usermem" ) // Mappable represents a memory-mappable object, a mutable mapping from uint64 -// offsets to (platform.File, uint64 File offset) pairs. +// offsets to (File, uint64 File offset) pairs. // // See mm/mm.go for Mappable's place in the lock order. // @@ -75,7 +74,7 @@ type Mappable interface { // Translations are valid until invalidated by a callback to // MappingSpace.Invalidate or until the caller removes its mapping of the // translated range. Mappable implementations must ensure that at least one - // reference is held on all pages in a platform.File that may be the result + // reference is held on all pages in a File that may be the result // of a valid Translation. // // Preconditions: required.Length() > 0. optional.IsSupersetOf(required). @@ -101,7 +100,7 @@ type Translation struct { Source MappableRange // File is the mapped file. - File platform.File + File File // Offset is the offset into File at which this Translation begins. Offset uint64 @@ -111,9 +110,9 @@ type Translation struct { Perms usermem.AccessType } -// FileRange returns the platform.FileRange represented by t. -func (t Translation) FileRange() platform.FileRange { - return platform.FileRange{t.Offset, t.Offset + t.Source.Length()} +// FileRange returns the FileRange represented by t. +func (t Translation) FileRange() FileRange { + return FileRange{t.Offset, t.Offset + t.Source.Length()} } // CheckTranslateResult returns an error if (ts, terr) does not satisfy all @@ -235,8 +234,11 @@ type InvalidateOpts struct { // coincidental; fs.File implements MappingIdentity, and some // fs.InodeOperations implement Mappable.) type MappingIdentity interface { - // MappingIdentity is reference-counted. - refs.RefCounter + // IncRef increments the MappingIdentity's reference count. + IncRef() + + // DecRef decrements the MappingIdentity's reference count. + DecRef(ctx context.Context) // MappedName returns the application-visible name shown in // /proc/[pid]/maps. @@ -358,4 +360,57 @@ type MMapOpts struct { // // TODO(jamieliu): Replace entirely with MappingIdentity? Hint string + + // Force means to skip validation checks of Addr and Length. It can be + // used to create special mappings below mm.layout.MinAddr and + // mm.layout.MaxAddr. It has to be used with caution. + // + // If Force is true, Unmap and Fixed must be true. + Force bool +} + +// File represents a host file that may be mapped into an platform.AddressSpace. +type File interface { + // All pages in a File are reference-counted. + + // IncRef increments the reference count on all pages in fr. + // + // Preconditions: fr.Start and fr.End must be page-aligned. fr.Length() > + // 0. At least one reference must be held on all pages in fr. (The File + // interface does not provide a way to acquire an initial reference; + // implementors may define mechanisms for doing so.) + IncRef(fr FileRange) + + // DecRef decrements the reference count on all pages in fr. + // + // Preconditions: fr.Start and fr.End must be page-aligned. fr.Length() > + // 0. At least one reference must be held on all pages in fr. + DecRef(fr FileRange) + + // MapInternal returns a mapping of the given file offsets in the invoking + // process' address space for reading and writing. + // + // Note that fr.Start and fr.End need not be page-aligned. + // + // Preconditions: fr.Length() > 0. At least one reference must be held on + // all pages in fr. + // + // Postconditions: The returned mapping is valid as long as at least one + // reference is held on the mapped pages. + MapInternal(fr FileRange, at usermem.AccessType) (safemem.BlockSeq, error) + + // FD returns the file descriptor represented by the File. + // + // The only permitted operation on the returned file descriptor is to map + // pages from it consistent with the requirements of AddressSpace.MapFile. + FD() int +} + +// FileRange represents a range of uint64 offsets into a File. +// +// type FileRange <generated using go_generics> + +// String implements fmt.Stringer.String. +func (fr FileRange) String() string { + return fmt.Sprintf("[%#x, %#x)", fr.Start, fr.End) } |