diff options
| -rw-r--r-- | pkg/abi/linux/BUILD | 2 | ||||
| -rw-r--r-- | pkg/abi/linux/epoll.go | 7 | ||||
| -rw-r--r-- | pkg/abi/linux/epoll_amd64.go | 25 | ||||
| -rw-r--r-- | pkg/abi/linux/epoll_arm64.go | 24 | ||||
| -rw-r--r-- | pkg/sentry/syscalls/linux/sys_epoll.go | 3 | ||||
| -rw-r--r-- | pkg/sentry/vfs/epoll.go | 19 |
6 files changed, 61 insertions, 19 deletions
diff --git a/pkg/abi/linux/BUILD b/pkg/abi/linux/BUILD index b7015367b..a89f34d4b 100644 --- a/pkg/abi/linux/BUILD +++ b/pkg/abi/linux/BUILD @@ -17,6 +17,8 @@ go_library( "dev.go", "elf.go", "epoll.go", + "epoll_amd64.go", + "epoll_arm64.go", "errors.go", "eventfd.go", "exec.go", diff --git a/pkg/abi/linux/epoll.go b/pkg/abi/linux/epoll.go index 0e881aa3c..6e4de69da 100644 --- a/pkg/abi/linux/epoll.go +++ b/pkg/abi/linux/epoll.go @@ -14,13 +14,6 @@ package linux -// EpollEvent is equivalent to struct epoll_event from epoll(2). -type EpollEvent struct { - Events uint32 - Fd int32 - Data int32 -} - // Event masks. const ( EPOLLIN = 0x1 diff --git a/pkg/abi/linux/epoll_amd64.go b/pkg/abi/linux/epoll_amd64.go new file mode 100644 index 000000000..57041491c --- /dev/null +++ b/pkg/abi/linux/epoll_amd64.go @@ -0,0 +1,25 @@ +// Copyright 2019 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package linux + +// EpollEvent is equivalent to struct epoll_event from epoll(2). +type EpollEvent struct { + Events uint32 + // Linux makes struct epoll_event::data a __u64. We represent it as + // [2]int32 because, on amd64, Linux also makes struct epoll_event + // __attribute__((packed)), such that there is no padding between Events + // and Data. + Data [2]int32 +} diff --git a/pkg/abi/linux/epoll_arm64.go b/pkg/abi/linux/epoll_arm64.go new file mode 100644 index 000000000..62ef5821e --- /dev/null +++ b/pkg/abi/linux/epoll_arm64.go @@ -0,0 +1,24 @@ +// Copyright 2020 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package linux + +// EpollEvent is equivalent to struct epoll_event from epoll(2). +type EpollEvent struct { + Events uint32 + // Linux makes struct epoll_event a __u64, necessitating 4 bytes of padding + // here. + _ int32 + Data [2]int32 +} diff --git a/pkg/sentry/syscalls/linux/sys_epoll.go b/pkg/sentry/syscalls/linux/sys_epoll.go index 5f11b496c..fbef5b376 100644 --- a/pkg/sentry/syscalls/linux/sys_epoll.go +++ b/pkg/sentry/syscalls/linux/sys_epoll.go @@ -83,8 +83,7 @@ func EpollCtl(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Sysc } mask = waiter.EventMaskFromLinux(e.Events) - data[0] = e.Fd - data[1] = e.Data + data = e.Data } // Perform the requested operations. diff --git a/pkg/sentry/vfs/epoll.go b/pkg/sentry/vfs/epoll.go index 7c83f9a5a..eed41139b 100644 --- a/pkg/sentry/vfs/epoll.go +++ b/pkg/sentry/vfs/epoll.go @@ -85,8 +85,8 @@ type epollInterest struct { ready bool epollInterestEntry - // userData is the epoll_data_t associated with this epollInterest. - // userData is protected by epoll.mu. + // userData is the struct epoll_event::data associated with this + // epollInterest. userData is protected by epoll.mu. userData [2]int32 } @@ -157,7 +157,7 @@ func (ep *EpollInstance) Seek(ctx context.Context, offset int64, whence int32) ( // AddInterest implements the semantics of EPOLL_CTL_ADD. // // Preconditions: A reference must be held on file. -func (ep *EpollInstance) AddInterest(file *FileDescription, num int32, mask uint32, userData [2]int32) error { +func (ep *EpollInstance) AddInterest(file *FileDescription, num int32, event linux.EpollEvent) error { // Check for cyclic polling if necessary. subep, _ := file.impl.(*EpollInstance) if subep != nil { @@ -183,12 +183,12 @@ func (ep *EpollInstance) AddInterest(file *FileDescription, num int32, mask uint } // Register interest in file. - mask |= linux.EPOLLERR | linux.EPOLLRDHUP + mask := event.Events | linux.EPOLLERR | linux.EPOLLRDHUP epi := &epollInterest{ epoll: ep, key: key, mask: mask, - userData: userData, + userData: event.Data, } ep.interest[key] = epi wmask := waiter.EventMaskFromLinux(mask) @@ -236,7 +236,7 @@ func (ep *EpollInstance) mightPollRecursive(ep2 *EpollInstance, remainingRecursi // ModifyInterest implements the semantics of EPOLL_CTL_MOD. // // Preconditions: A reference must be held on file. -func (ep *EpollInstance) ModifyInterest(file *FileDescription, num int32, mask uint32, userData [2]int32) error { +func (ep *EpollInstance) ModifyInterest(file *FileDescription, num int32, event linux.EpollEvent) error { ep.interestMu.Lock() defer ep.interestMu.Unlock() @@ -250,13 +250,13 @@ func (ep *EpollInstance) ModifyInterest(file *FileDescription, num int32, mask u } // Update epi for the next call to ep.ReadEvents(). + mask := event.Events | linux.EPOLLERR | linux.EPOLLRDHUP ep.mu.Lock() epi.mask = mask - epi.userData = userData + epi.userData = event.Data ep.mu.Unlock() // Re-register with the new mask. - mask |= linux.EPOLLERR | linux.EPOLLRDHUP file.EventUnregister(&epi.waiter) wmask := waiter.EventMaskFromLinux(mask) file.EventRegister(&epi.waiter, wmask) @@ -363,8 +363,7 @@ func (ep *EpollInstance) ReadEvents(events []linux.EpollEvent) int { // Report ievents. events[i] = linux.EpollEvent{ Events: ievents.ToLinux(), - Fd: epi.userData[0], - Data: epi.userData[1], + Data: epi.userData, } i++ if i == len(events) { |