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-rw-r--r--pkg/abi/linux/aio.go60
-rw-r--r--pkg/sentry/kernel/BUILD1
-rw-r--r--pkg/sentry/kernel/aio.go81
-rw-r--r--pkg/sentry/kernel/context.go53
-rw-r--r--pkg/sentry/kernel/kernel.go10
-rw-r--r--pkg/sentry/kernel/threads.go7
-rw-r--r--pkg/sentry/syscalls/linux/sys_aio.go169
-rw-r--r--pkg/sentry/syscalls/linux/vfs2/BUILD3
-rw-r--r--pkg/sentry/syscalls/linux/vfs2/aio.go216
-rw-r--r--pkg/sentry/syscalls/linux/vfs2/vfs2.go6
10 files changed, 431 insertions, 175 deletions
diff --git a/pkg/abi/linux/aio.go b/pkg/abi/linux/aio.go
index 3c6e0079d..86ee3f8b5 100644
--- a/pkg/abi/linux/aio.go
+++ b/pkg/abi/linux/aio.go
@@ -14,7 +14,63 @@
package linux
+import "encoding/binary"
+
+// AIORingSize is sizeof(struct aio_ring).
+const AIORingSize = 32
+
+// I/O commands.
const (
- // AIORingSize is sizeof(struct aio_ring).
- AIORingSize = 32
+ IOCB_CMD_PREAD = 0
+ IOCB_CMD_PWRITE = 1
+ IOCB_CMD_FSYNC = 2
+ IOCB_CMD_FDSYNC = 3
+ // 4 was the experimental IOCB_CMD_PREADX.
+ IOCB_CMD_POLL = 5
+ IOCB_CMD_NOOP = 6
+ IOCB_CMD_PREADV = 7
+ IOCB_CMD_PWRITEV = 8
)
+
+// I/O flags.
+const (
+ IOCB_FLAG_RESFD = 1
+ IOCB_FLAG_IOPRIO = 2
+)
+
+// IOCallback describes an I/O request.
+//
+// The priority field is currently ignored in the implementation below. Also
+// note that the IOCB_FLAG_RESFD feature is not supported.
+type IOCallback struct {
+ Data uint64
+ Key uint32
+ _ uint32
+
+ OpCode uint16
+ ReqPrio int16
+ FD int32
+
+ Buf uint64
+ Bytes uint64
+ Offset int64
+
+ Reserved2 uint64
+ Flags uint32
+
+ // eventfd to signal if IOCB_FLAG_RESFD is set in flags.
+ ResFD int32
+}
+
+// IOEvent describes an I/O result.
+//
+// +stateify savable
+type IOEvent struct {
+ Data uint64
+ Obj uint64
+ Result int64
+ Result2 int64
+}
+
+// IOEventSize is the size of an ioEvent encoded.
+var IOEventSize = binary.Size(IOEvent{})
diff --git a/pkg/sentry/kernel/BUILD b/pkg/sentry/kernel/BUILD
index a28eab8b8..1510a7c26 100644
--- a/pkg/sentry/kernel/BUILD
+++ b/pkg/sentry/kernel/BUILD
@@ -85,6 +85,7 @@ go_library(
name = "kernel",
srcs = [
"abstract_socket_namespace.go",
+ "aio.go",
"context.go",
"fd_table.go",
"fd_table_unsafe.go",
diff --git a/pkg/sentry/kernel/aio.go b/pkg/sentry/kernel/aio.go
new file mode 100644
index 000000000..0ac78c0b8
--- /dev/null
+++ b/pkg/sentry/kernel/aio.go
@@ -0,0 +1,81 @@
+// 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 kernel
+
+import (
+ "time"
+
+ "gvisor.dev/gvisor/pkg/context"
+ "gvisor.dev/gvisor/pkg/log"
+)
+
+// AIOCallback is an function that does asynchronous I/O on behalf of a task.
+type AIOCallback func(context.Context)
+
+// QueueAIO queues an AIOCallback which will be run asynchronously.
+func (t *Task) QueueAIO(cb AIOCallback) {
+ ctx := taskAsyncContext{t: t}
+ wg := &t.TaskSet().aioGoroutines
+ wg.Add(1)
+ go func() {
+ cb(ctx)
+ wg.Done()
+ }()
+}
+
+type taskAsyncContext struct {
+ context.NoopSleeper
+ t *Task
+}
+
+// Debugf implements log.Logger.Debugf.
+func (ctx taskAsyncContext) Debugf(format string, v ...interface{}) {
+ ctx.t.Debugf(format, v...)
+}
+
+// Infof implements log.Logger.Infof.
+func (ctx taskAsyncContext) Infof(format string, v ...interface{}) {
+ ctx.t.Infof(format, v...)
+}
+
+// Warningf implements log.Logger.Warningf.
+func (ctx taskAsyncContext) Warningf(format string, v ...interface{}) {
+ ctx.t.Warningf(format, v...)
+}
+
+// IsLogging implements log.Logger.IsLogging.
+func (ctx taskAsyncContext) IsLogging(level log.Level) bool {
+ return ctx.t.IsLogging(level)
+}
+
+// Deadline implements context.Context.Deadline.
+func (ctx taskAsyncContext) Deadline() (time.Time, bool) {
+ return ctx.t.Deadline()
+}
+
+// Done implements context.Context.Done.
+func (ctx taskAsyncContext) Done() <-chan struct{} {
+ return ctx.t.Done()
+}
+
+// Err implements context.Context.Err.
+func (ctx taskAsyncContext) Err() error {
+ return ctx.t.Err()
+}
+
+// Value implements context.Context.Value.
+func (ctx taskAsyncContext) Value(key interface{}) interface{} {
+ return ctx.t.Value(key)
+}
diff --git a/pkg/sentry/kernel/context.go b/pkg/sentry/kernel/context.go
index 0c40bf315..dd5f0f5fa 100644
--- a/pkg/sentry/kernel/context.go
+++ b/pkg/sentry/kernel/context.go
@@ -18,7 +18,6 @@ import (
"time"
"gvisor.dev/gvisor/pkg/context"
- "gvisor.dev/gvisor/pkg/log"
)
// contextID is the kernel package's type for context.Context.Value keys.
@@ -113,55 +112,3 @@ func (*Task) Done() <-chan struct{} {
func (*Task) Err() error {
return nil
}
-
-// AsyncContext returns a context.Context that may be used by goroutines that
-// do work on behalf of t and therefore share its contextual values, but are
-// not t's task goroutine (e.g. asynchronous I/O).
-func (t *Task) AsyncContext() context.Context {
- return taskAsyncContext{t: t}
-}
-
-type taskAsyncContext struct {
- context.NoopSleeper
- t *Task
-}
-
-// Debugf implements log.Logger.Debugf.
-func (ctx taskAsyncContext) Debugf(format string, v ...interface{}) {
- ctx.t.Debugf(format, v...)
-}
-
-// Infof implements log.Logger.Infof.
-func (ctx taskAsyncContext) Infof(format string, v ...interface{}) {
- ctx.t.Infof(format, v...)
-}
-
-// Warningf implements log.Logger.Warningf.
-func (ctx taskAsyncContext) Warningf(format string, v ...interface{}) {
- ctx.t.Warningf(format, v...)
-}
-
-// IsLogging implements log.Logger.IsLogging.
-func (ctx taskAsyncContext) IsLogging(level log.Level) bool {
- return ctx.t.IsLogging(level)
-}
-
-// Deadline implements context.Context.Deadline.
-func (ctx taskAsyncContext) Deadline() (time.Time, bool) {
- return ctx.t.Deadline()
-}
-
-// Done implements context.Context.Done.
-func (ctx taskAsyncContext) Done() <-chan struct{} {
- return ctx.t.Done()
-}
-
-// Err implements context.Context.Err.
-func (ctx taskAsyncContext) Err() error {
- return ctx.t.Err()
-}
-
-// Value implements context.Context.Value.
-func (ctx taskAsyncContext) Value(key interface{}) interface{} {
- return ctx.t.Value(key)
-}
diff --git a/pkg/sentry/kernel/kernel.go b/pkg/sentry/kernel/kernel.go
index 52491da7a..554a42e05 100644
--- a/pkg/sentry/kernel/kernel.go
+++ b/pkg/sentry/kernel/kernel.go
@@ -452,9 +452,7 @@ func (k *Kernel) SaveTo(w io.Writer) error {
return err
}
- // Ensure that all pending asynchronous work is complete:
- // - inode and mount release
- // - asynchronuous IO
+ // Ensure that all inode and mount release operations have completed.
fs.AsyncBarrier()
// Once all fs work has completed (flushed references have all been released),
@@ -1249,13 +1247,15 @@ func (k *Kernel) Kill(es ExitStatus) {
}
// Pause requests that all tasks in k temporarily stop executing, and blocks
-// until all tasks in k have stopped. Multiple calls to Pause nest and require
-// an equal number of calls to Unpause to resume execution.
+// until all tasks and asynchronous I/O operations in k have stopped. Multiple
+// calls to Pause nest and require an equal number of calls to Unpause to
+// resume execution.
func (k *Kernel) Pause() {
k.extMu.Lock()
k.tasks.BeginExternalStop()
k.extMu.Unlock()
k.tasks.runningGoroutines.Wait()
+ k.tasks.aioGoroutines.Wait()
}
// Unpause ends the effect of a previous call to Pause. If Unpause is called
diff --git a/pkg/sentry/kernel/threads.go b/pkg/sentry/kernel/threads.go
index bf2dabb6e..872e1a82d 100644
--- a/pkg/sentry/kernel/threads.go
+++ b/pkg/sentry/kernel/threads.go
@@ -87,6 +87,13 @@ type TaskSet struct {
// at time of save (but note that this is not necessarily the same thing as
// sync.WaitGroup's zero value).
runningGoroutines sync.WaitGroup `state:"nosave"`
+
+ // aioGoroutines is the number of goroutines running async I/O
+ // callbacks.
+ //
+ // aioGoroutines is not saved but is required to be zero at the time of
+ // save.
+ aioGoroutines sync.WaitGroup `state:"nosave"`
}
// newTaskSet returns a new, empty TaskSet.
diff --git a/pkg/sentry/syscalls/linux/sys_aio.go b/pkg/sentry/syscalls/linux/sys_aio.go
index d781d6a04..ba2557c52 100644
--- a/pkg/sentry/syscalls/linux/sys_aio.go
+++ b/pkg/sentry/syscalls/linux/sys_aio.go
@@ -15,8 +15,8 @@
package linux
import (
- "encoding/binary"
-
+ "gvisor.dev/gvisor/pkg/abi/linux"
+ "gvisor.dev/gvisor/pkg/context"
"gvisor.dev/gvisor/pkg/sentry/arch"
"gvisor.dev/gvisor/pkg/sentry/fs"
"gvisor.dev/gvisor/pkg/sentry/kernel"
@@ -27,59 +27,6 @@ import (
"gvisor.dev/gvisor/pkg/usermem"
)
-// I/O commands.
-const (
- _IOCB_CMD_PREAD = 0
- _IOCB_CMD_PWRITE = 1
- _IOCB_CMD_FSYNC = 2
- _IOCB_CMD_FDSYNC = 3
- _IOCB_CMD_NOOP = 6
- _IOCB_CMD_PREADV = 7
- _IOCB_CMD_PWRITEV = 8
-)
-
-// I/O flags.
-const (
- _IOCB_FLAG_RESFD = 1
-)
-
-// ioCallback describes an I/O request.
-//
-// The priority field is currently ignored in the implementation below. Also
-// note that the IOCB_FLAG_RESFD feature is not supported.
-type ioCallback struct {
- Data uint64
- Key uint32
- Reserved1 uint32
-
- OpCode uint16
- ReqPrio int16
- FD int32
-
- Buf uint64
- Bytes uint64
- Offset int64
-
- Reserved2 uint64
- Flags uint32
-
- // eventfd to signal if IOCB_FLAG_RESFD is set in flags.
- ResFD int32
-}
-
-// ioEvent describes an I/O result.
-//
-// +stateify savable
-type ioEvent struct {
- Data uint64
- Obj uint64
- Result int64
- Result2 int64
-}
-
-// ioEventSize is the size of an ioEvent encoded.
-var ioEventSize = binary.Size(ioEvent{})
-
// IoSetup implements linux syscall io_setup(2).
func IoSetup(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) {
nrEvents := args[0].Int()
@@ -192,7 +139,7 @@ func IoGetevents(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.S
}
}
- ev := v.(*ioEvent)
+ ev := v.(*linux.IOEvent)
// Copy out the result.
if _, err := t.CopyOut(eventsAddr, ev); err != nil {
@@ -204,7 +151,7 @@ func IoGetevents(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.S
}
// Keep rolling.
- eventsAddr += usermem.Addr(ioEventSize)
+ eventsAddr += usermem.Addr(linux.IOEventSize)
}
// Everything finished.
@@ -231,7 +178,7 @@ func waitForRequest(ctx *mm.AIOContext, t *kernel.Task, haveDeadline bool, deadl
}
// memoryFor returns appropriate memory for the given callback.
-func memoryFor(t *kernel.Task, cb *ioCallback) (usermem.IOSequence, error) {
+func memoryFor(t *kernel.Task, cb *linux.IOCallback) (usermem.IOSequence, error) {
bytes := int(cb.Bytes)
if bytes < 0 {
// Linux also requires that this field fit in ssize_t.
@@ -242,17 +189,17 @@ func memoryFor(t *kernel.Task, cb *ioCallback) (usermem.IOSequence, error) {
// we have no guarantee that t's AddressSpace will be active during the
// I/O.
switch cb.OpCode {
- case _IOCB_CMD_PREAD, _IOCB_CMD_PWRITE:
+ case linux.IOCB_CMD_PREAD, linux.IOCB_CMD_PWRITE:
return t.SingleIOSequence(usermem.Addr(cb.Buf), bytes, usermem.IOOpts{
AddressSpaceActive: false,
})
- case _IOCB_CMD_PREADV, _IOCB_CMD_PWRITEV:
+ case linux.IOCB_CMD_PREADV, linux.IOCB_CMD_PWRITEV:
return t.IovecsIOSequence(usermem.Addr(cb.Buf), bytes, usermem.IOOpts{
AddressSpaceActive: false,
})
- case _IOCB_CMD_FSYNC, _IOCB_CMD_FDSYNC, _IOCB_CMD_NOOP:
+ case linux.IOCB_CMD_FSYNC, linux.IOCB_CMD_FDSYNC, linux.IOCB_CMD_NOOP:
return usermem.IOSequence{}, nil
default:
@@ -261,54 +208,62 @@ func memoryFor(t *kernel.Task, cb *ioCallback) (usermem.IOSequence, error) {
}
}
-func performCallback(t *kernel.Task, file *fs.File, cbAddr usermem.Addr, cb *ioCallback, ioseq usermem.IOSequence, ctx *mm.AIOContext, eventFile *fs.File) {
- if ctx.Dead() {
- ctx.CancelPendingRequest()
- return
- }
- ev := &ioEvent{
- Data: cb.Data,
- Obj: uint64(cbAddr),
- }
+// IoCancel implements linux syscall io_cancel(2).
+//
+// It is not presently supported (ENOSYS indicates no support on this
+// architecture).
+func IoCancel(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) {
+ return 0, nil, syserror.ENOSYS
+}
- // Construct a context.Context that will not be interrupted if t is
- // interrupted.
- c := t.AsyncContext()
+// LINT.IfChange
- var err error
- switch cb.OpCode {
- case _IOCB_CMD_PREAD, _IOCB_CMD_PREADV:
- ev.Result, err = file.Preadv(c, ioseq, cb.Offset)
- case _IOCB_CMD_PWRITE, _IOCB_CMD_PWRITEV:
- ev.Result, err = file.Pwritev(c, ioseq, cb.Offset)
- case _IOCB_CMD_FSYNC:
- err = file.Fsync(c, 0, fs.FileMaxOffset, fs.SyncAll)
- case _IOCB_CMD_FDSYNC:
- err = file.Fsync(c, 0, fs.FileMaxOffset, fs.SyncData)
- }
+func getAIOCallback(t *kernel.Task, file *fs.File, cbAddr usermem.Addr, cb *linux.IOCallback, ioseq usermem.IOSequence, actx *mm.AIOContext, eventFile *fs.File) kernel.AIOCallback {
+ return func(ctx context.Context) {
+ if actx.Dead() {
+ actx.CancelPendingRequest()
+ return
+ }
+ ev := &linux.IOEvent{
+ Data: cb.Data,
+ Obj: uint64(cbAddr),
+ }
- // Update the result.
- if err != nil {
- err = handleIOError(t, ev.Result != 0 /* partial */, err, nil /* never interrupted */, "aio", file)
- ev.Result = -int64(kernel.ExtractErrno(err, 0))
- }
+ var err error
+ switch cb.OpCode {
+ case linux.IOCB_CMD_PREAD, linux.IOCB_CMD_PREADV:
+ ev.Result, err = file.Preadv(ctx, ioseq, cb.Offset)
+ case linux.IOCB_CMD_PWRITE, linux.IOCB_CMD_PWRITEV:
+ ev.Result, err = file.Pwritev(ctx, ioseq, cb.Offset)
+ case linux.IOCB_CMD_FSYNC:
+ err = file.Fsync(ctx, 0, fs.FileMaxOffset, fs.SyncAll)
+ case linux.IOCB_CMD_FDSYNC:
+ err = file.Fsync(ctx, 0, fs.FileMaxOffset, fs.SyncData)
+ }
+
+ // Update the result.
+ if err != nil {
+ err = handleIOError(t, ev.Result != 0 /* partial */, err, nil /* never interrupted */, "aio", file)
+ ev.Result = -int64(kernel.ExtractErrno(err, 0))
+ }
- file.DecRef()
+ file.DecRef()
- // Queue the result for delivery.
- ctx.FinishRequest(ev)
+ // Queue the result for delivery.
+ actx.FinishRequest(ev)
- // Notify the event file if one was specified. This needs to happen
- // *after* queueing the result to avoid racing with the thread we may
- // wake up.
- if eventFile != nil {
- eventFile.FileOperations.(*eventfd.EventOperations).Signal(1)
- eventFile.DecRef()
+ // Notify the event file if one was specified. This needs to happen
+ // *after* queueing the result to avoid racing with the thread we may
+ // wake up.
+ if eventFile != nil {
+ eventFile.FileOperations.(*eventfd.EventOperations).Signal(1)
+ eventFile.DecRef()
+ }
}
}
// submitCallback processes a single callback.
-func submitCallback(t *kernel.Task, id uint64, cb *ioCallback, cbAddr usermem.Addr) error {
+func submitCallback(t *kernel.Task, id uint64, cb *linux.IOCallback, cbAddr usermem.Addr) error {
file := t.GetFile(cb.FD)
if file == nil {
// File not found.
@@ -318,7 +273,7 @@ func submitCallback(t *kernel.Task, id uint64, cb *ioCallback, cbAddr usermem.Ad
// Was there an eventFD? Extract it.
var eventFile *fs.File
- if cb.Flags&_IOCB_FLAG_RESFD != 0 {
+ if cb.Flags&linux.IOCB_FLAG_RESFD != 0 {
eventFile = t.GetFile(cb.ResFD)
if eventFile == nil {
// Bad FD.
@@ -340,7 +295,7 @@ func submitCallback(t *kernel.Task, id uint64, cb *ioCallback, cbAddr usermem.Ad
// Check offset for reads/writes.
switch cb.OpCode {
- case _IOCB_CMD_PREAD, _IOCB_CMD_PREADV, _IOCB_CMD_PWRITE, _IOCB_CMD_PWRITEV:
+ case linux.IOCB_CMD_PREAD, linux.IOCB_CMD_PREADV, linux.IOCB_CMD_PWRITE, linux.IOCB_CMD_PWRITEV:
if cb.Offset < 0 {
return syserror.EINVAL
}
@@ -366,7 +321,7 @@ func submitCallback(t *kernel.Task, id uint64, cb *ioCallback, cbAddr usermem.Ad
// Perform the request asynchronously.
file.IncRef()
- fs.Async(func() { performCallback(t, file, cbAddr, cb, ioseq, ctx, eventFile) })
+ t.QueueAIO(getAIOCallback(t, file, cbAddr, cb, ioseq, ctx, eventFile))
// All set.
return nil
@@ -395,7 +350,7 @@ func IoSubmit(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Sysc
}
// Copy in this callback.
- var cb ioCallback
+ var cb linux.IOCallback
cbAddr := usermem.Addr(t.Arch().Value(cbAddrNative))
if _, err := t.CopyIn(cbAddr, &cb); err != nil {
@@ -424,10 +379,4 @@ func IoSubmit(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Sysc
return uintptr(nrEvents), nil, nil
}
-// IoCancel implements linux syscall io_cancel(2).
-//
-// It is not presently supported (ENOSYS indicates no support on this
-// architecture).
-func IoCancel(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) {
- return 0, nil, syserror.ENOSYS
-}
+// LINT.ThenChange(vfs2/aio.go)
diff --git a/pkg/sentry/syscalls/linux/vfs2/BUILD b/pkg/sentry/syscalls/linux/vfs2/BUILD
index 9f93f4354..c301a0991 100644
--- a/pkg/sentry/syscalls/linux/vfs2/BUILD
+++ b/pkg/sentry/syscalls/linux/vfs2/BUILD
@@ -5,6 +5,7 @@ package(licenses = ["notice"])
go_library(
name = "vfs2",
srcs = [
+ "aio.go",
"epoll.go",
"eventfd.go",
"execve.go",
@@ -40,6 +41,7 @@ go_library(
"//pkg/abi/linux",
"//pkg/binary",
"//pkg/bits",
+ "//pkg/context",
"//pkg/fspath",
"//pkg/gohacks",
"//pkg/sentry/arch",
@@ -57,6 +59,7 @@ go_library(
"//pkg/sentry/limits",
"//pkg/sentry/loader",
"//pkg/sentry/memmap",
+ "//pkg/sentry/mm",
"//pkg/sentry/socket",
"//pkg/sentry/socket/control",
"//pkg/sentry/socket/unix/transport",
diff --git a/pkg/sentry/syscalls/linux/vfs2/aio.go b/pkg/sentry/syscalls/linux/vfs2/aio.go
new file mode 100644
index 000000000..e5cdefc50
--- /dev/null
+++ b/pkg/sentry/syscalls/linux/vfs2/aio.go
@@ -0,0 +1,216 @@
+// Copyright 2018 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 vfs2
+
+import (
+ "gvisor.dev/gvisor/pkg/abi/linux"
+ "gvisor.dev/gvisor/pkg/context"
+ "gvisor.dev/gvisor/pkg/sentry/arch"
+ "gvisor.dev/gvisor/pkg/sentry/fsimpl/eventfd"
+ "gvisor.dev/gvisor/pkg/sentry/kernel"
+ "gvisor.dev/gvisor/pkg/sentry/mm"
+ slinux "gvisor.dev/gvisor/pkg/sentry/syscalls/linux"
+ "gvisor.dev/gvisor/pkg/sentry/vfs"
+ "gvisor.dev/gvisor/pkg/syserror"
+ "gvisor.dev/gvisor/pkg/usermem"
+)
+
+// IoSubmit implements linux syscall io_submit(2).
+func IoSubmit(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) {
+ id := args[0].Uint64()
+ nrEvents := args[1].Int()
+ addr := args[2].Pointer()
+
+ if nrEvents < 0 {
+ return 0, nil, syserror.EINVAL
+ }
+
+ for i := int32(0); i < nrEvents; i++ {
+ // Copy in the address.
+ cbAddrNative := t.Arch().Native(0)
+ if _, err := t.CopyIn(addr, cbAddrNative); err != nil {
+ if i > 0 {
+ // Some successful.
+ return uintptr(i), nil, nil
+ }
+ // Nothing done.
+ return 0, nil, err
+ }
+
+ // Copy in this callback.
+ var cb linux.IOCallback
+ cbAddr := usermem.Addr(t.Arch().Value(cbAddrNative))
+ if _, err := t.CopyIn(cbAddr, &cb); err != nil {
+ if i > 0 {
+ // Some have been successful.
+ return uintptr(i), nil, nil
+ }
+ // Nothing done.
+ return 0, nil, err
+ }
+
+ // Process this callback.
+ if err := submitCallback(t, id, &cb, cbAddr); err != nil {
+ if i > 0 {
+ // Partial success.
+ return uintptr(i), nil, nil
+ }
+ // Nothing done.
+ return 0, nil, err
+ }
+
+ // Advance to the next one.
+ addr += usermem.Addr(t.Arch().Width())
+ }
+
+ return uintptr(nrEvents), nil, nil
+}
+
+// submitCallback processes a single callback.
+func submitCallback(t *kernel.Task, id uint64, cb *linux.IOCallback, cbAddr usermem.Addr) error {
+ if cb.Reserved2 != 0 {
+ return syserror.EINVAL
+ }
+
+ fd := t.GetFileVFS2(cb.FD)
+ if fd == nil {
+ return syserror.EBADF
+ }
+ defer fd.DecRef()
+
+ // Was there an eventFD? Extract it.
+ var eventFD *vfs.FileDescription
+ if cb.Flags&linux.IOCB_FLAG_RESFD != 0 {
+ eventFD = t.GetFileVFS2(cb.ResFD)
+ if eventFD == nil {
+ return syserror.EBADF
+ }
+ defer eventFD.DecRef()
+
+ // Check that it is an eventfd.
+ if _, ok := eventFD.Impl().(*eventfd.EventFileDescription); !ok {
+ return syserror.EINVAL
+ }
+ }
+
+ ioseq, err := memoryFor(t, cb)
+ if err != nil {
+ return err
+ }
+
+ // Check offset for reads/writes.
+ switch cb.OpCode {
+ case linux.IOCB_CMD_PREAD, linux.IOCB_CMD_PREADV, linux.IOCB_CMD_PWRITE, linux.IOCB_CMD_PWRITEV:
+ if cb.Offset < 0 {
+ return syserror.EINVAL
+ }
+ }
+
+ // Prepare the request.
+ aioCtx, ok := t.MemoryManager().LookupAIOContext(t, id)
+ if !ok {
+ return syserror.EINVAL
+ }
+ if ready := aioCtx.Prepare(); !ready {
+ // Context is busy.
+ return syserror.EAGAIN
+ }
+
+ if eventFD != nil {
+ // The request is set. Make sure there's a ref on the file.
+ //
+ // This is necessary when the callback executes on completion,
+ // which is also what will release this reference.
+ eventFD.IncRef()
+ }
+
+ // Perform the request asynchronously.
+ fd.IncRef()
+ t.QueueAIO(getAIOCallback(t, fd, eventFD, cbAddr, cb, ioseq, aioCtx))
+ return nil
+}
+
+func getAIOCallback(t *kernel.Task, fd, eventFD *vfs.FileDescription, cbAddr usermem.Addr, cb *linux.IOCallback, ioseq usermem.IOSequence, aioCtx *mm.AIOContext) kernel.AIOCallback {
+ return func(ctx context.Context) {
+ if aioCtx.Dead() {
+ aioCtx.CancelPendingRequest()
+ return
+ }
+ ev := &linux.IOEvent{
+ Data: cb.Data,
+ Obj: uint64(cbAddr),
+ }
+
+ var err error
+ switch cb.OpCode {
+ case linux.IOCB_CMD_PREAD, linux.IOCB_CMD_PREADV:
+ ev.Result, err = fd.PRead(ctx, ioseq, cb.Offset, vfs.ReadOptions{})
+ case linux.IOCB_CMD_PWRITE, linux.IOCB_CMD_PWRITEV:
+ ev.Result, err = fd.PWrite(ctx, ioseq, cb.Offset, vfs.WriteOptions{})
+ case linux.IOCB_CMD_FSYNC, linux.IOCB_CMD_FDSYNC:
+ err = fd.Sync(ctx)
+ }
+
+ // Update the result.
+ if err != nil {
+ err = slinux.HandleIOErrorVFS2(t, ev.Result != 0 /* partial */, err, nil /* never interrupted */, "aio", fd)
+ ev.Result = -int64(kernel.ExtractErrno(err, 0))
+ }
+
+ fd.DecRef()
+
+ // Queue the result for delivery.
+ aioCtx.FinishRequest(ev)
+
+ // Notify the event file if one was specified. This needs to happen
+ // *after* queueing the result to avoid racing with the thread we may
+ // wake up.
+ if eventFD != nil {
+ eventFD.Impl().(*eventfd.EventFileDescription).Signal(1)
+ eventFD.DecRef()
+ }
+ }
+}
+
+// memoryFor returns appropriate memory for the given callback.
+func memoryFor(t *kernel.Task, cb *linux.IOCallback) (usermem.IOSequence, error) {
+ bytes := int(cb.Bytes)
+ if bytes < 0 {
+ // Linux also requires that this field fit in ssize_t.
+ return usermem.IOSequence{}, syserror.EINVAL
+ }
+
+ // Since this I/O will be asynchronous with respect to t's task goroutine,
+ // we have no guarantee that t's AddressSpace will be active during the
+ // I/O.
+ switch cb.OpCode {
+ case linux.IOCB_CMD_PREAD, linux.IOCB_CMD_PWRITE:
+ return t.SingleIOSequence(usermem.Addr(cb.Buf), bytes, usermem.IOOpts{
+ AddressSpaceActive: false,
+ })
+
+ case linux.IOCB_CMD_PREADV, linux.IOCB_CMD_PWRITEV:
+ return t.IovecsIOSequence(usermem.Addr(cb.Buf), bytes, usermem.IOOpts{
+ AddressSpaceActive: false,
+ })
+
+ case linux.IOCB_CMD_FSYNC, linux.IOCB_CMD_FDSYNC, linux.IOCB_CMD_NOOP:
+ return usermem.IOSequence{}, nil
+
+ default:
+ // Not a supported command.
+ return usermem.IOSequence{}, syserror.EINVAL
+ }
+}
diff --git a/pkg/sentry/syscalls/linux/vfs2/vfs2.go b/pkg/sentry/syscalls/linux/vfs2/vfs2.go
index 954c82f97..caa6a98ff 100644
--- a/pkg/sentry/syscalls/linux/vfs2/vfs2.go
+++ b/pkg/sentry/syscalls/linux/vfs2/vfs2.go
@@ -105,11 +105,7 @@ func Override() {
s.Table[197] = syscalls.Supported("removexattr", Removexattr)
s.Table[198] = syscalls.Supported("lremovexattr", Lremovexattr)
s.Table[199] = syscalls.Supported("fremovexattr", Fremovexattr)
- delete(s.Table, 206) // io_setup
- delete(s.Table, 207) // io_destroy
- delete(s.Table, 208) // io_getevents
- delete(s.Table, 209) // io_submit
- delete(s.Table, 210) // io_cancel
+ s.Table[209] = syscalls.PartiallySupported("io_submit", IoSubmit, "Generally supported with exceptions. User ring optimizations are not implemented.", []string{"gvisor.dev/issue/204"})
s.Table[213] = syscalls.Supported("epoll_create", EpollCreate)
s.Table[217] = syscalls.Supported("getdents64", Getdents64)
delete(s.Table, 221) // fdavise64
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-06 22:40:46 +0000