diff options
Diffstat (limited to 'internal/syscallcompat/quirks_linux.go')
-rw-r--r-- | internal/syscallcompat/quirks_linux.go | 36 |
1 files changed, 36 insertions, 0 deletions
diff --git a/internal/syscallcompat/quirks_linux.go b/internal/syscallcompat/quirks_linux.go new file mode 100644 index 0000000..ffdbfab --- /dev/null +++ b/internal/syscallcompat/quirks_linux.go @@ -0,0 +1,36 @@ +package syscallcompat + +import ( + "golang.org/x/sys/unix" + + "github.com/rfjakob/gocryptfs/internal/tlog" +) + +// DetectQuirks decides if there are known quirks on the backing filesystem +// that need to be workarounded. +// +// Tested by tests/root_test.TestBtrfsQuirks +func DetectQuirks(cipherdir string) (q uint64) { + const ( + // From Linux' man statfs + BTRFS_SUPER_MAGIC = 0x9123683e + ) + + var st unix.Statfs_t + err := unix.Statfs(cipherdir, &st) + if err != nil { + tlog.Warn.Printf("DetectQuirks: Statfs on %q failed: %v", cipherdir, err) + return 0 + } + + // Preallocation on Btrfs is broken ( https://github.com/rfjakob/gocryptfs/issues/395 ) + // and slow ( https://github.com/rfjakob/gocryptfs/issues/63 ). + // + // Cast to uint32 avoids compile error on arm: "constant 2435016766 overflows int32" + if uint32(st.Type) == BTRFS_SUPER_MAGIC { + logQuirk("Btrfs detected, forcing -noprealloc. See https://github.com/rfjakob/gocryptfs/issues/395 for why.") + q |= QuirkBrokenFalloc + } + + return q +} |