diff options
Diffstat (limited to 'pkg/sentry/memmap')
| -rw-r--r-- | pkg/sentry/memmap/mapping_set.go | 4 | ||||
| -rw-r--r-- | pkg/sentry/memmap/mapping_set_impl.go | 32 | ||||
| -rw-r--r-- | pkg/sentry/memmap/memmap.go | 59 |
3 files changed, 56 insertions, 39 deletions
diff --git a/pkg/sentry/memmap/mapping_set.go b/pkg/sentry/memmap/mapping_set.go index d609c1ae0..457ed87f8 100644 --- a/pkg/sentry/memmap/mapping_set.go +++ b/pkg/sentry/memmap/mapping_set.go @@ -177,7 +177,7 @@ func subsetMapping(wholeRange, subsetRange MappableRange, ms MappingSpace, addr // AddMapping adds the given mapping and returns the set of MappableRanges that // previously had no mappings. // -// Preconditions: As for Mappable.AddMapping. +// Preconditions: Same as Mappable.AddMapping. func (s *MappingSet) AddMapping(ms MappingSpace, ar usermem.AddrRange, offset uint64, writable bool) []MappableRange { mr := MappableRange{offset, offset + uint64(ar.Length())} var mapped []MappableRange @@ -204,7 +204,7 @@ func (s *MappingSet) AddMapping(ms MappingSpace, ar usermem.AddrRange, offset ui // RemoveMapping removes the given mapping and returns the set of // MappableRanges that now have no mappings. // -// Preconditions: As for Mappable.RemoveMapping. +// Preconditions: Same as Mappable.RemoveMapping. func (s *MappingSet) RemoveMapping(ms MappingSpace, ar usermem.AddrRange, offset uint64, writable bool) []MappableRange { mr := MappableRange{offset, offset + uint64(ar.Length())} var unmapped []MappableRange diff --git a/pkg/sentry/memmap/mapping_set_impl.go b/pkg/sentry/memmap/mapping_set_impl.go index cb4281950..eda4579e8 100644 --- a/pkg/sentry/memmap/mapping_set_impl.go +++ b/pkg/sentry/memmap/mapping_set_impl.go @@ -343,7 +343,9 @@ func (s *MappingSet) InsertWithoutMerging(gap MappingGapIterator, r MappableRang // and returns an iterator to the inserted segment. All existing iterators // (including gap, but not including the returned iterator) are invalidated. // -// Preconditions: r.Start >= gap.Start(); r.End <= gap.End(). +// Preconditions: +// * r.Start >= gap.Start(). +// * r.End <= gap.End(). func (s *MappingSet) InsertWithoutMergingUnchecked(gap MappingGapIterator, r MappableRange, val MappingsOfRange) MappingIterator { gap = gap.node.rebalanceBeforeInsert(gap) splitMaxGap := MappingtrackGaps != 0 && (gap.node.nrSegments == 0 || gap.Range().Length() == gap.node.maxGap.Get()) @@ -1097,12 +1099,10 @@ func (seg MappingIterator) End() uint64 { // does not invalidate any iterators. // // Preconditions: -// -// - r.Length() > 0. -// -// - The new range must not overlap an existing one: If seg.NextSegment().Ok(), -// then r.end <= seg.NextSegment().Start(); if seg.PrevSegment().Ok(), then -// r.start >= seg.PrevSegment().End(). +// * r.Length() > 0. +// * The new range must not overlap an existing one: +// * If seg.NextSegment().Ok(), then r.end <= seg.NextSegment().Start(). +// * If seg.PrevSegment().Ok(), then r.start >= seg.PrevSegment().End(). func (seg MappingIterator) SetRangeUnchecked(r MappableRange) { seg.node.keys[seg.index] = r } @@ -1127,8 +1127,9 @@ func (seg MappingIterator) SetRange(r MappableRange) { // SetStartUnchecked mutates the iterated segment's start. This operation does // not invalidate any iterators. // -// Preconditions: The new start must be valid: start < seg.End(); if -// seg.PrevSegment().Ok(), then start >= seg.PrevSegment().End(). +// Preconditions: The new start must be valid: +// * start < seg.End() +// * If seg.PrevSegment().Ok(), then start >= seg.PrevSegment().End(). func (seg MappingIterator) SetStartUnchecked(start uint64) { seg.node.keys[seg.index].Start = start } @@ -1150,8 +1151,9 @@ func (seg MappingIterator) SetStart(start uint64) { // SetEndUnchecked mutates the iterated segment's end. This operation does not // invalidate any iterators. // -// Preconditions: The new end must be valid: end > seg.Start(); if -// seg.NextSegment().Ok(), then end <= seg.NextSegment().Start(). +// Preconditions: The new end must be valid: +// * end > seg.Start(). +// * If seg.NextSegment().Ok(), then end <= seg.NextSegment().Start(). func (seg MappingIterator) SetEndUnchecked(end uint64) { seg.node.keys[seg.index].End = end } @@ -1571,9 +1573,11 @@ func (s *MappingSet) ExportSortedSlices() *MappingSegmentDataSlices { // ImportSortedSlice initializes the given set from the given slice. // -// Preconditions: s must be empty. sds must represent a valid set (the segments -// in sds must have valid lengths that do not overlap). The segments in sds -// must be sorted in ascending key order. +// Preconditions: +// * s must be empty. +// * sds must represent a valid set (the segments in sds must have valid +// lengths that do not overlap). +// * The segments in sds must be sorted in ascending key order. func (s *MappingSet) ImportSortedSlices(sds *MappingSegmentDataSlices) error { if !s.IsEmpty() { return fmt.Errorf("cannot import into non-empty set %v", s) diff --git a/pkg/sentry/memmap/memmap.go b/pkg/sentry/memmap/memmap.go index 65d83096f..a44fa2b95 100644 --- a/pkg/sentry/memmap/memmap.go +++ b/pkg/sentry/memmap/memmap.go @@ -28,9 +28,9 @@ import ( // // See mm/mm.go for Mappable's place in the lock order. // -// Preconditions: For all Mappable methods, usermem.AddrRanges and -// MappableRanges must be non-empty (Length() != 0), and usermem.Addrs and -// Mappable offsets must be page-aligned. +// All Mappable methods have the following preconditions: +// * usermem.AddrRanges and MappableRanges must be non-empty (Length() != 0). +// * usermem.Addrs and Mappable offsets must be page-aligned. type Mappable interface { // AddMapping notifies the Mappable of a mapping from addresses ar in ms to // offsets [offset, offset+ar.Length()) in this Mappable. @@ -48,8 +48,10 @@ type Mappable interface { // addresses ar in ms to offsets [offset, offset+ar.Length()) in this // Mappable. // - // Preconditions: offset+ar.Length() does not overflow. The removed mapping - // must exist. writable must match the corresponding call to AddMapping. + // Preconditions: + // * offset+ar.Length() does not overflow. + // * The removed mapping must exist. writable must match the + // corresponding call to AddMapping. RemoveMapping(ctx context.Context, ms MappingSpace, ar usermem.AddrRange, offset uint64, writable bool) // CopyMapping notifies the Mappable of an attempt to copy a mapping in ms @@ -60,9 +62,10 @@ type Mappable interface { // CopyMapping is only called when a mapping is copied within a given // MappingSpace; it is analogous to Linux's vm_operations_struct::mremap. // - // Preconditions: offset+srcAR.Length() and offset+dstAR.Length() do not - // overflow. The mapping at srcAR must exist. writable must match the - // corresponding call to AddMapping. + // Preconditions: + // * offset+srcAR.Length() and offset+dstAR.Length() do not overflow. + // * The mapping at srcAR must exist. writable must match the + // corresponding call to AddMapping. CopyMapping(ctx context.Context, ms MappingSpace, srcAR, dstAR usermem.AddrRange, offset uint64, writable bool) error // Translate returns the Mappable's current mappings for at least the range @@ -77,11 +80,14 @@ type Mappable interface { // 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). - // required and optional must be page-aligned. The caller must have - // established a mapping for all of the queried offsets via a previous call - // to AddMapping. The caller is responsible for ensuring that calls to - // Translate synchronize with invalidation. + // Preconditions: + // * required.Length() > 0. + // * optional.IsSupersetOf(required). + // * required and optional must be page-aligned. + // * The caller must have established a mapping for all of the queried + // offsets via a previous call to AddMapping. + // * The caller is responsible for ensuring that calls to Translate + // synchronize with invalidation. // // Postconditions: See CheckTranslateResult. Translate(ctx context.Context, required, optional MappableRange, at usermem.AccessType) ([]Translation, error) @@ -118,7 +124,7 @@ func (t Translation) FileRange() FileRange { // CheckTranslateResult returns an error if (ts, terr) does not satisfy all // postconditions for Mappable.Translate(required, optional, at). // -// Preconditions: As for Mappable.Translate. +// Preconditions: Same as Mappable.Translate. func CheckTranslateResult(required, optional MappableRange, at usermem.AccessType, ts []Translation, terr error) error { // Verify that the inputs to Mappable.Translate were valid. if !required.WellFormed() || required.Length() <= 0 { @@ -214,7 +220,9 @@ type MappingSpace interface { // Invalidate must not take any locks preceding mm.MemoryManager.activeMu // in the lock order. // - // Preconditions: ar.Length() != 0. ar must be page-aligned. + // Preconditions: + // * ar.Length() != 0. + // * ar must be page-aligned. Invalidate(ar usermem.AddrRange, opts InvalidateOpts) } @@ -375,16 +383,20 @@ type File interface { // 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.) + // 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. + // 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 @@ -392,8 +404,9 @@ type File interface { // // 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. + // 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. |