diff options
| -rw-r--r-- | internal/inomap/inomap.go | 21 | ||||
| -rw-r--r-- | internal/inomap/inomap_test.go | 5 |
2 files changed, 15 insertions, 11 deletions
diff --git a/internal/inomap/inomap.go b/internal/inomap/inomap.go index 0f7ade3..1c012d9 100644 --- a/internal/inomap/inomap.go +++ b/internal/inomap/inomap.go @@ -3,8 +3,8 @@ // // Format of the returned inode numbers: // -// [spill bit = 0][15 bit namespace id][48 bit passthru inode number] -// [spill bit = 1][63 bit spill inode number ] +// [spill bit = 0][15 bit namespace id][48 bit passthru inode number] = 64 bit translated inode number +// [spill bit = 1][63 bit counter ] = 64 bit spill inode number // // Each (Dev, Tag) tuple gets a namespace id assigned. The original inode // number is then passed through in the lower 48 bits. @@ -16,6 +16,7 @@ package inomap import ( "log" + "math" "sync" "syscall" @@ -27,10 +28,8 @@ const ( maxNamespaceId = 1<<15 - 1 // max value of 48 bit passthru inode number maxPassthruIno = 1<<48 - 1 - // max value of 63 bit spill inode number - maxSpillIno = 1<<63 - 1 - // bit 63 is used as the spill bit - spillBit = 1 << 63 + // the spill inode number space starts at 0b10000...0. + spillSpaceStart = 1 << 63 ) // InoMap stores the maps using for inode number translation. @@ -57,7 +56,7 @@ func New(rootDev uint64) *InoMap { namespaceMap: make(map[namespaceData]uint16), namespaceNext: 0, spillMap: make(map[QIno]uint64), - spillNext: 0, + spillNext: spillSpaceStart, } if rootDev > 0 { // Reserve namespace 0 for rootDev @@ -74,18 +73,18 @@ func (m *InoMap) spill(in QIno) (out uint64) { out, found := m.spillMap[in] if found { - return out | spillBit + return out } - if m.spillNext >= maxSpillIno { + if m.spillNext == math.MaxUint64 { log.Panicf("spillMap overflow: spillNext = 0x%x", m.spillNext) } out = m.spillNext m.spillNext++ m.spillMap[in] = out - return out | spillBit + return out } -// Translate maps the passed-in (device, inode) pair to a unique inode number. +// Translate maps the passed-in (device, tag, inode) tuple to a unique inode number. func (m *InoMap) Translate(in QIno) (out uint64) { m.Lock() defer m.Unlock() diff --git a/internal/inomap/inomap_test.go b/internal/inomap/inomap_test.go index 9ec2932..430ec94 100644 --- a/internal/inomap/inomap_test.go +++ b/internal/inomap/inomap_test.go @@ -5,6 +5,11 @@ import ( "testing" ) +const ( + // bit 63 is used as the spill bit + spillBit = 1 << 63 +) + func TestTranslate(t *testing.T) { m := New(0) q := QIno{Ino: 1} |