diff options
Diffstat (limited to 'pkg')
-rw-r--r-- | pkg/sentry/fs/fsutil/inode_cached.go | 66 | ||||
-rw-r--r-- | pkg/sentry/fs/fsutil/inode_cached_test.go | 39 | ||||
-rw-r--r-- | pkg/sentry/fs/gofer/inode.go | 14 |
3 files changed, 48 insertions, 71 deletions
diff --git a/pkg/sentry/fs/fsutil/inode_cached.go b/pkg/sentry/fs/fsutil/inode_cached.go index 707ca76d2..5e7e861d2 100644 --- a/pkg/sentry/fs/fsutil/inode_cached.go +++ b/pkg/sentry/fs/fsutil/inode_cached.go @@ -22,6 +22,7 @@ import ( "gvisor.googlesource.com/gvisor/pkg/log" "gvisor.googlesource.com/gvisor/pkg/sentry/context" "gvisor.googlesource.com/gvisor/pkg/sentry/fs" + "gvisor.googlesource.com/gvisor/pkg/sentry/kernel/time" ktime "gvisor.googlesource.com/gvisor/pkg/sentry/kernel/time" "gvisor.googlesource.com/gvisor/pkg/sentry/memmap" "gvisor.googlesource.com/gvisor/pkg/sentry/platform" @@ -141,10 +142,6 @@ type CachedFileObject interface { // // FD is called iff the file has been memory mapped. This implies that // the file was opened (see fs.InodeOperations.GetFile). - // - // FIXME: This interface seems to be - // fundamentally broken. We should clarify CachingInodeOperation's - // behavior with metadata. FD() int } @@ -190,16 +187,14 @@ func (c *CachingInodeOperations) SetPermissions(ctx context.Context, inode *fs.I c.attrMu.Lock() defer c.attrMu.Unlock() + now := ktime.NowFromContext(ctx) masked := fs.AttrMask{Perms: true} if err := c.backingFile.SetMaskedAttributes(ctx, masked, fs.UnstableAttr{Perms: perms}); err != nil { return false } c.attr.Perms = perms - // FIXME: Clarify CachingInodeOperations behavior with metadata. - c.dirtyAttr.Perms = true - c.touchStatusChangeTimeLocked(ctx) + c.touchStatusChangeTimeLocked(now) return true - } // SetOwner implements fs.InodeOperations.SetOwner. @@ -211,6 +206,7 @@ func (c *CachingInodeOperations) SetOwner(ctx context.Context, inode *fs.Inode, c.attrMu.Lock() defer c.attrMu.Unlock() + now := ktime.NowFromContext(ctx) masked := fs.AttrMask{ UID: owner.UID.Ok(), GID: owner.GID.Ok(), @@ -220,15 +216,11 @@ func (c *CachingInodeOperations) SetOwner(ctx context.Context, inode *fs.Inode, } if owner.UID.Ok() { c.attr.Owner.UID = owner.UID - // FIXME: Clarify CachingInodeOperations behavior with metadata. - c.dirtyAttr.UID = true } if owner.GID.Ok() { c.attr.Owner.GID = owner.GID - // FIXME: Clarify CachingInodeOperations behavior with metadata. - c.dirtyAttr.GID = true } - c.touchStatusChangeTimeLocked(ctx) + c.touchStatusChangeTimeLocked(now) return nil } @@ -260,15 +252,11 @@ func (c *CachingInodeOperations) SetTimestamps(ctx context.Context, inode *fs.In } if !ts.ATimeOmit { c.attr.AccessTime = ts.ATime - // FIXME: Clarify CachingInodeOperations behavior with metadata. - c.dirtyAttr.AccessTime = true } if !ts.MTimeOmit { c.attr.ModificationTime = ts.MTime - // FIXME: Clarify CachingInodeOperations behavior with metadata. - c.dirtyAttr.ModificationTime = true } - c.touchStatusChangeTimeLocked(ctx) + c.touchStatusChangeTimeLocked(now) return nil } @@ -279,21 +267,17 @@ func (c *CachingInodeOperations) Truncate(ctx context.Context, inode *fs.Inode, // c.attr.Size is protected by both c.attrMu and c.dataMu. c.dataMu.Lock() - if err := c.backingFile.SetMaskedAttributes(ctx, fs.AttrMask{ - Size: true, - }, fs.UnstableAttr{ - Size: size, - }); err != nil { + now := ktime.NowFromContext(ctx) + masked := fs.AttrMask{Size: true} + attr := fs.UnstableAttr{Size: size} + if err := c.backingFile.SetMaskedAttributes(ctx, masked, attr); err != nil { c.dataMu.Unlock() return err } oldSize := c.attr.Size - if oldSize != size { - c.attr.Size = size - // FIXME: Clarify CachingInodeOperations behavior with metadata. - c.dirtyAttr.Size = true - c.touchModificationTimeLocked(ctx) - } + c.attr.Size = size + c.touchModificationTimeLocked(now) + // We drop c.dataMu here so that we can lock c.mapsMu and invalidate // mappings below. This allows concurrent calls to Read/Translate/etc. // These functions synchronize with an in-progress Truncate by refusing to @@ -346,6 +330,10 @@ func (c *CachingInodeOperations) WriteOut(ctx context.Context, inode *fs.Inode) return err } + // SyncDirtyAll above would have grown if needed. On shrinks, the backing + // file is called directly, so size is never needs to be updated. + c.dirtyAttr.Size = false + // Write out cached attributes. if err := c.backingFile.SetMaskedAttributes(ctx, c.dirtyAttr, c.attr); err != nil { c.attrMu.Unlock() @@ -363,7 +351,7 @@ func (c *CachingInodeOperations) WriteOut(ctx context.Context, inode *fs.Inode) func (c *CachingInodeOperations) IncLinks(ctx context.Context) { c.attrMu.Lock() c.attr.Links++ - c.touchModificationTimeLocked(ctx) + c.touchModificationTimeLocked(ktime.NowFromContext(ctx)) c.attrMu.Unlock() } @@ -371,7 +359,7 @@ func (c *CachingInodeOperations) IncLinks(ctx context.Context) { func (c *CachingInodeOperations) DecLinks(ctx context.Context) { c.attrMu.Lock() c.attr.Links-- - c.touchModificationTimeLocked(ctx) + c.touchModificationTimeLocked(ktime.NowFromContext(ctx)) c.attrMu.Unlock() } @@ -384,7 +372,7 @@ func (c *CachingInodeOperations) TouchAccessTime(ctx context.Context, inode *fs. } c.attrMu.Lock() - c.touchAccessTimeLocked(ctx) + c.touchAccessTimeLocked(ktime.NowFromContext(ctx)) c.attrMu.Unlock() } @@ -392,8 +380,8 @@ func (c *CachingInodeOperations) TouchAccessTime(ctx context.Context, inode *fs. // time. // // Preconditions: c.attrMu is locked for writing. -func (c *CachingInodeOperations) touchAccessTimeLocked(ctx context.Context) { - c.attr.AccessTime = ktime.NowFromContext(ctx) +func (c *CachingInodeOperations) touchAccessTimeLocked(now time.Time) { + c.attr.AccessTime = now c.dirtyAttr.AccessTime = true } @@ -401,7 +389,7 @@ func (c *CachingInodeOperations) touchAccessTimeLocked(ctx context.Context) { // in-place to the current time. func (c *CachingInodeOperations) TouchModificationTime(ctx context.Context) { c.attrMu.Lock() - c.touchModificationTimeLocked(ctx) + c.touchModificationTimeLocked(ktime.NowFromContext(ctx)) c.attrMu.Unlock() } @@ -409,8 +397,7 @@ func (c *CachingInodeOperations) TouchModificationTime(ctx context.Context) { // change time in-place to the current time. // // Preconditions: c.attrMu is locked for writing. -func (c *CachingInodeOperations) touchModificationTimeLocked(ctx context.Context) { - now := ktime.NowFromContext(ctx) +func (c *CachingInodeOperations) touchModificationTimeLocked(now time.Time) { c.attr.ModificationTime = now c.dirtyAttr.ModificationTime = true c.attr.StatusChangeTime = now @@ -421,8 +408,7 @@ func (c *CachingInodeOperations) touchModificationTimeLocked(ctx context.Context // in-place to the current time. // // Preconditions: c.attrMu is locked for writing. -func (c *CachingInodeOperations) touchStatusChangeTimeLocked(ctx context.Context) { - now := ktime.NowFromContext(ctx) +func (c *CachingInodeOperations) touchStatusChangeTimeLocked(now time.Time) { c.attr.StatusChangeTime = now c.dirtyAttr.StatusChangeTime = true } @@ -513,7 +499,7 @@ func (c *CachingInodeOperations) Write(ctx context.Context, src usermem.IOSequen c.attrMu.Lock() // Compare Linux's mm/filemap.c:__generic_file_write_iter() => file_update_time(). - c.touchModificationTimeLocked(ctx) + c.touchModificationTimeLocked(ktime.NowFromContext(ctx)) n, err := src.CopyInTo(ctx, &inodeReadWriter{ctx, c, offset}) c.attrMu.Unlock() return n, err diff --git a/pkg/sentry/fs/fsutil/inode_cached_test.go b/pkg/sentry/fs/fsutil/inode_cached_test.go index 9c9391511..2a8a1639c 100644 --- a/pkg/sentry/fs/fsutil/inode_cached_test.go +++ b/pkg/sentry/fs/fsutil/inode_cached_test.go @@ -17,7 +17,6 @@ package fsutil import ( "bytes" "io" - "reflect" "testing" "gvisor.googlesource.com/gvisor/pkg/sentry/context" @@ -66,9 +65,6 @@ func TestSetPermissions(t *testing.T) { } // Did permissions change? - if !iops.dirtyAttr.Perms { - t.Fatalf("got perms not dirty, want dirty") - } if iops.attr.Perms != perms { t.Fatalf("got perms +%v, want +%v", iops.attr.Perms, perms) } @@ -85,9 +81,9 @@ func TestSetPermissions(t *testing.T) { func TestSetTimestamps(t *testing.T) { ctx := contexttest.Context(t) for _, test := range []struct { - desc string - ts fs.TimeSpec - wantDirty fs.AttrMask + desc string + ts fs.TimeSpec + wantChanged fs.AttrMask }{ { desc: "noop", @@ -95,7 +91,7 @@ func TestSetTimestamps(t *testing.T) { ATimeOmit: true, MTimeOmit: true, }, - wantDirty: fs.AttrMask{}, + wantChanged: fs.AttrMask{}, }, { desc: "access time only", @@ -103,9 +99,8 @@ func TestSetTimestamps(t *testing.T) { ATime: ktime.NowFromContext(ctx), MTimeOmit: true, }, - wantDirty: fs.AttrMask{ - AccessTime: true, - StatusChangeTime: true, + wantChanged: fs.AttrMask{ + AccessTime: true, }, }, { @@ -114,9 +109,8 @@ func TestSetTimestamps(t *testing.T) { ATimeOmit: true, MTime: ktime.NowFromContext(ctx), }, - wantDirty: fs.AttrMask{ + wantChanged: fs.AttrMask{ ModificationTime: true, - StatusChangeTime: true, }, }, { @@ -125,10 +119,9 @@ func TestSetTimestamps(t *testing.T) { ATime: ktime.NowFromContext(ctx), MTime: ktime.NowFromContext(ctx), }, - wantDirty: fs.AttrMask{ + wantChanged: fs.AttrMask{ AccessTime: true, ModificationTime: true, - StatusChangeTime: true, }, }, { @@ -137,10 +130,9 @@ func TestSetTimestamps(t *testing.T) { ATimeSetSystemTime: true, MTimeSetSystemTime: true, }, - wantDirty: fs.AttrMask{ + wantChanged: fs.AttrMask{ AccessTime: true, ModificationTime: true, - StatusChangeTime: true, }, }, } { @@ -159,10 +151,7 @@ func TestSetTimestamps(t *testing.T) { if err := iops.SetTimestamps(ctx, nil, test.ts); err != nil { t.Fatalf("SetTimestamps got error %v, want nil", err) } - if !reflect.DeepEqual(iops.dirtyAttr, test.wantDirty) { - t.Fatalf("dirty got %+v, want %+v", iops.dirtyAttr, test.wantDirty) - } - if iops.dirtyAttr.AccessTime { + if test.wantChanged.AccessTime { if !iops.attr.AccessTime.After(uattr.AccessTime) { t.Fatalf("diritied access time did not advance, want %v > %v", iops.attr.AccessTime, uattr.AccessTime) } @@ -173,7 +162,7 @@ func TestSetTimestamps(t *testing.T) { t.Fatalf("dirtied status change time did not advance") } } - if iops.dirtyAttr.ModificationTime { + if test.wantChanged.ModificationTime { if !iops.attr.ModificationTime.After(uattr.ModificationTime) { t.Fatalf("diritied modification time did not advance") } @@ -200,16 +189,10 @@ func TestTruncate(t *testing.T) { if err := iops.Truncate(ctx, nil, uattr.Size); err != nil { t.Fatalf("Truncate got error %v, want nil", err) } - if iops.dirtyAttr.Size { - t.Fatalf("Truncate caused size to be dirtied") - } var size int64 = 4096 if err := iops.Truncate(ctx, nil, size); err != nil { t.Fatalf("Truncate got error %v, want nil", err) } - if !iops.dirtyAttr.Size { - t.Fatalf("Truncate caused size to not be dirtied") - } if iops.attr.Size != size { t.Fatalf("Truncate got %d, want %d", iops.attr.Size, size) } diff --git a/pkg/sentry/fs/gofer/inode.go b/pkg/sentry/fs/gofer/inode.go index 1dc0ca0db..16435169a 100644 --- a/pkg/sentry/fs/gofer/inode.go +++ b/pkg/sentry/fs/gofer/inode.go @@ -247,6 +247,7 @@ func (i *inodeFileState) SetMaskedAttributes(ctx context.Context, mask fs.AttrMa // skipSetAttr checks if attribute change can be skipped. It can be skipped // when: // - Mask is empty +// - Mask contains only attributes that cannot be set in the gofer // - Mask contains only atime and/or mtime, and host FD exists // // Updates to atime and mtime can be skipped because cached value will be @@ -254,15 +255,22 @@ func (i *inodeFileState) SetMaskedAttributes(ctx context.Context, mask fs.AttrMa // Skipping atime updates is particularly important to reduce the number of // operations sent to the Gofer for readonly files. func (i *inodeFileState) skipSetAttr(mask fs.AttrMask) bool { - if mask.Empty() { + // First remove attributes that cannot be updated. + cpy := mask + cpy.Type = false + cpy.DeviceID = false + cpy.InodeID = false + cpy.BlockSize = false + cpy.Usage = false + cpy.Links = false + if cpy.Empty() { return true } - cpy := mask + // Then check if more than just atime and mtime is being set. cpy.AccessTime = false cpy.ModificationTime = false if !cpy.Empty() { - // More than just atime and mtime is being set. return false } |