diff options
author | Jamie Liu <jamieliu@google.com> | 2019-03-12 10:28:23 -0700 |
---|---|---|
committer | Shentubot <shentubot@google.com> | 2019-03-12 10:29:16 -0700 |
commit | 8930e79ebf72a0cc69e9b81af37bcbb57b115543 (patch) | |
tree | c71cae2be099a7923a1c7681ebe7c4322f189f4a /pkg/sentry/memmap | |
parent | 6e6dbf0e566270ae96a4db81d9d04275d0fffb00 (diff) |
Clarify the platform.File interface.
- Redefine some memmap.Mappable, platform.File, and platform.Memory
semantics in terms of File reference counts (no functional change).
- Make AddressSpace.MapFile take a platform.File instead of a raw FD,
and replace platform.File.MapInto with platform.File.FD. This allows
kvm.AddressSpace.MapFile to always use platform.File.MapInternal instead
of maintaining its own (redundant) cache of file mappings in the sentry
address space.
PiperOrigin-RevId: 238044504
Change-Id: Ib73a11e4275c0da0126d0194aa6c6017a9cef64f
Diffstat (limited to 'pkg/sentry/memmap')
-rw-r--r-- | pkg/sentry/memmap/memmap.go | 14 |
1 files changed, 7 insertions, 7 deletions
diff --git a/pkg/sentry/memmap/memmap.go b/pkg/sentry/memmap/memmap.go index cf20b11e3..70cdf428b 100644 --- a/pkg/sentry/memmap/memmap.go +++ b/pkg/sentry/memmap/memmap.go @@ -70,11 +70,13 @@ type Mappable interface { // of offsets specified by required, and at most the range of offsets // specified by optional. at is the set of access types that may be // performed using the returned Translations. If not all required offsets - // are translated, it returns a non-nil error explaining why. Returned - // translations, and any mappings returned by platform.File.MapInternal for - // translated platform.Files, are valid until invalidated by a call back to + // are translated, it returns a non-nil error explaining why. + // + // Translations are valid until invalidated by a callback to // MappingSpace.Invalidate or until the caller removes its mapping of the - // translated range. + // 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 + // of a valid Translation. // // Preconditions: required.Length() > 0. optional.IsSupersetOf(required). // required and optional must be page-aligned. The caller must have @@ -98,9 +100,7 @@ type Translation struct { // Source is the translated range in the Mappable. Source MappableRange - // File is the mapped file. When the Translation is invalidated, pages - // mapped by File.MapInto must be unmapped, and pages mapped by - // File.MapInternal become invalid. + // File is the mapped file. File platform.File // Offset is the offset into File at which this Translation begins. |