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path: root/pkg/sentry/kernel/task_syscall.go
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Diffstat (limited to 'pkg/sentry/kernel/task_syscall.go')
-rw-r--r--pkg/sentry/kernel/task_syscall.go69
1 files changed, 1 insertions, 68 deletions
diff --git a/pkg/sentry/kernel/task_syscall.go b/pkg/sentry/kernel/task_syscall.go
index a5903b0b5..2dbf86547 100644
--- a/pkg/sentry/kernel/task_syscall.go
+++ b/pkg/sentry/kernel/task_syscall.go
@@ -29,75 +29,8 @@ import (
"gvisor.dev/gvisor/pkg/usermem"
)
-// SyscallRestartErrno represents a ERESTART* errno defined in the Linux's kernel
-// include/linux/errno.h. These errnos are never returned to userspace
-// directly, but are used to communicate the expected behavior of an
-// interrupted syscall from the syscall to signal handling.
-type SyscallRestartErrno int
-
-// These numeric values are significant because ptrace syscall exit tracing can
-// observe them.
-//
-// For all of the following errnos, if the syscall is not interrupted by a
-// signal delivered to a user handler, the syscall is restarted.
-const (
- // ERESTARTSYS is returned by an interrupted syscall to indicate that it
- // should be converted to EINTR if interrupted by a signal delivered to a
- // user handler without SA_RESTART set, and restarted otherwise.
- ERESTARTSYS = SyscallRestartErrno(512)
-
- // ERESTARTNOINTR is returned by an interrupted syscall to indicate that it
- // should always be restarted.
- ERESTARTNOINTR = SyscallRestartErrno(513)
-
- // ERESTARTNOHAND is returned by an interrupted syscall to indicate that it
- // should be converted to EINTR if interrupted by a signal delivered to a
- // user handler, and restarted otherwise.
- ERESTARTNOHAND = SyscallRestartErrno(514)
-
- // ERESTART_RESTARTBLOCK is returned by an interrupted syscall to indicate
- // that it should be restarted using a custom function. The interrupted
- // syscall must register a custom restart function by calling
- // Task.SetRestartSyscallFn.
- ERESTART_RESTARTBLOCK = SyscallRestartErrno(516)
-)
-
var vsyscallCount = metric.MustCreateNewUint64Metric("/kernel/vsyscall_count", false /* sync */, "Number of times vsyscalls were invoked by the application")
-// Error implements error.Error.
-func (e SyscallRestartErrno) Error() string {
- // Descriptions are borrowed from strace.
- switch e {
- case ERESTARTSYS:
- return "to be restarted if SA_RESTART is set"
- case ERESTARTNOINTR:
- return "to be restarted"
- case ERESTARTNOHAND:
- return "to be restarted if no handler"
- case ERESTART_RESTARTBLOCK:
- return "interrupted by signal"
- default:
- return "(unknown interrupt error)"
- }
-}
-
-// SyscallRestartErrnoFromReturn returns the SyscallRestartErrno represented by
-// rv, the value in a syscall return register.
-func SyscallRestartErrnoFromReturn(rv uintptr) (SyscallRestartErrno, bool) {
- switch int(rv) {
- case -int(ERESTARTSYS):
- return ERESTARTSYS, true
- case -int(ERESTARTNOINTR):
- return ERESTARTNOINTR, true
- case -int(ERESTARTNOHAND):
- return ERESTARTNOHAND, true
- case -int(ERESTART_RESTARTBLOCK):
- return ERESTART_RESTARTBLOCK, true
- default:
- return 0, false
- }
-}
-
// SyscallRestartBlock represents the restart block for a syscall restartable
// with a custom function. It encapsulates the state required to restart a
// syscall across a S/R.
@@ -447,7 +380,7 @@ func ExtractErrno(err error, sysno int) int {
return 0
case syscall.Errno:
return int(err)
- case SyscallRestartErrno:
+ case syserror.SyscallRestartErrno:
return int(err)
case *memmap.BusError:
// Bus errors may generate SIGBUS, but for syscalls they still