diff options
Diffstat (limited to 'pkg/sentry')
| -rw-r--r-- | pkg/sentry/kernel/task.go | 7 | ||||
| -rw-r--r-- | pkg/sentry/kernel/task_sched.go | 4 | ||||
| -rw-r--r-- | pkg/sentry/mm/mm.go | 6 | ||||
| -rw-r--r-- | pkg/sentry/mm/syscalls.go | 53 | ||||
| -rw-r--r-- | pkg/sentry/mm/vma.go | 3 | ||||
| -rw-r--r-- | pkg/sentry/syscalls/linux/BUILD | 1 | ||||
| -rw-r--r-- | pkg/sentry/syscalls/linux/linux64.go | 3 | ||||
| -rw-r--r-- | pkg/sentry/syscalls/linux/sys_mempolicy.go | 312 | ||||
| -rw-r--r-- | pkg/sentry/syscalls/linux/sys_mmap.go | 145 |
9 files changed, 382 insertions, 152 deletions
diff --git a/pkg/sentry/kernel/task.go b/pkg/sentry/kernel/task.go index f9378c2de..4d889422f 100644 --- a/pkg/sentry/kernel/task.go +++ b/pkg/sentry/kernel/task.go @@ -455,12 +455,13 @@ type Task struct { // single numa node, all policies are no-ops. We only track this information // so that we can return reasonable values if the application calls // get_mempolicy(2) after setting a non-default policy. Note that in the - // real syscall, nodemask can be longer than 4 bytes, but we always report a - // single node so never need to save more than a single bit. + // real syscall, nodemask can be longer than a single unsigned long, but we + // always report a single node so never need to save more than a single + // bit. // // numaPolicy and numaNodeMask are protected by mu. numaPolicy int32 - numaNodeMask uint32 + numaNodeMask uint64 // If netns is true, the task is in a non-root network namespace. Network // namespaces aren't currently implemented in full; being in a network diff --git a/pkg/sentry/kernel/task_sched.go b/pkg/sentry/kernel/task_sched.go index 5455f6ea9..1c94ab11b 100644 --- a/pkg/sentry/kernel/task_sched.go +++ b/pkg/sentry/kernel/task_sched.go @@ -622,14 +622,14 @@ func (t *Task) SetNiceness(n int) { } // NumaPolicy returns t's current numa policy. -func (t *Task) NumaPolicy() (policy int32, nodeMask uint32) { +func (t *Task) NumaPolicy() (policy int32, nodeMask uint64) { t.mu.Lock() defer t.mu.Unlock() return t.numaPolicy, t.numaNodeMask } // SetNumaPolicy sets t's numa policy. -func (t *Task) SetNumaPolicy(policy int32, nodeMask uint32) { +func (t *Task) SetNumaPolicy(policy int32, nodeMask uint64) { t.mu.Lock() defer t.mu.Unlock() t.numaPolicy = policy diff --git a/pkg/sentry/mm/mm.go b/pkg/sentry/mm/mm.go index 0a026ff8c..604866d04 100644 --- a/pkg/sentry/mm/mm.go +++ b/pkg/sentry/mm/mm.go @@ -276,6 +276,12 @@ type vma struct { mlockMode memmap.MLockMode + // numaPolicy is the NUMA policy for this vma set by mbind(). + numaPolicy int32 + + // numaNodemask is the NUMA nodemask for this vma set by mbind(). + numaNodemask uint64 + // If id is not nil, it controls the lifecycle of mappable and provides vma // metadata shown in /proc/[pid]/maps, and the vma holds a reference. id memmap.MappingIdentity diff --git a/pkg/sentry/mm/syscalls.go b/pkg/sentry/mm/syscalls.go index af1e53f5d..9cf136532 100644 --- a/pkg/sentry/mm/syscalls.go +++ b/pkg/sentry/mm/syscalls.go @@ -973,6 +973,59 @@ func (mm *MemoryManager) MLockAll(ctx context.Context, opts MLockAllOpts) error return nil } +// NumaPolicy implements the semantics of Linux's get_mempolicy(MPOL_F_ADDR). +func (mm *MemoryManager) NumaPolicy(addr usermem.Addr) (int32, uint64, error) { + mm.mappingMu.RLock() + defer mm.mappingMu.RUnlock() + vseg := mm.vmas.FindSegment(addr) + if !vseg.Ok() { + return 0, 0, syserror.EFAULT + } + vma := vseg.ValuePtr() + return vma.numaPolicy, vma.numaNodemask, nil +} + +// SetNumaPolicy implements the semantics of Linux's mbind(). +func (mm *MemoryManager) SetNumaPolicy(addr usermem.Addr, length uint64, policy int32, nodemask uint64) error { + if !addr.IsPageAligned() { + return syserror.EINVAL + } + // Linux allows this to overflow. + la, _ := usermem.Addr(length).RoundUp() + ar, ok := addr.ToRange(uint64(la)) + if !ok { + return syserror.EINVAL + } + if ar.Length() == 0 { + return nil + } + + mm.mappingMu.Lock() + defer mm.mappingMu.Unlock() + defer func() { + mm.vmas.MergeRange(ar) + mm.vmas.MergeAdjacent(ar) + }() + vseg := mm.vmas.LowerBoundSegment(ar.Start) + lastEnd := ar.Start + for { + if !vseg.Ok() || lastEnd < vseg.Start() { + // "EFAULT: ... there was an unmapped hole in the specified memory + // range specified [sic] by addr and len." - mbind(2) + return syserror.EFAULT + } + vseg = mm.vmas.Isolate(vseg, ar) + vma := vseg.ValuePtr() + vma.numaPolicy = policy + vma.numaNodemask = nodemask + lastEnd = vseg.End() + if ar.End <= lastEnd { + return nil + } + vseg, _ = vseg.NextNonEmpty() + } +} + // Decommit implements the semantics of Linux's madvise(MADV_DONTNEED). func (mm *MemoryManager) Decommit(addr usermem.Addr, length uint64) error { ar, ok := addr.ToRange(length) diff --git a/pkg/sentry/mm/vma.go b/pkg/sentry/mm/vma.go index 02203f79f..0af8de5b0 100644 --- a/pkg/sentry/mm/vma.go +++ b/pkg/sentry/mm/vma.go @@ -107,6 +107,7 @@ func (mm *MemoryManager) createVMALocked(ctx context.Context, opts memmap.MMapOp private: opts.Private, growsDown: opts.GrowsDown, mlockMode: opts.MLockMode, + numaPolicy: linux.MPOL_DEFAULT, id: opts.MappingIdentity, hint: opts.Hint, } @@ -436,6 +437,8 @@ func (vmaSetFunctions) Merge(ar1 usermem.AddrRange, vma1 vma, ar2 usermem.AddrRa vma1.private != vma2.private || vma1.growsDown != vma2.growsDown || vma1.mlockMode != vma2.mlockMode || + vma1.numaPolicy != vma2.numaPolicy || + vma1.numaNodemask != vma2.numaNodemask || vma1.id != vma2.id || vma1.hint != vma2.hint { return vma{}, false diff --git a/pkg/sentry/syscalls/linux/BUILD b/pkg/sentry/syscalls/linux/BUILD index f76989ae2..1c057526b 100644 --- a/pkg/sentry/syscalls/linux/BUILD +++ b/pkg/sentry/syscalls/linux/BUILD @@ -19,6 +19,7 @@ go_library( "sys_identity.go", "sys_inotify.go", "sys_lseek.go", + "sys_mempolicy.go", "sys_mmap.go", "sys_mount.go", "sys_pipe.go", diff --git a/pkg/sentry/syscalls/linux/linux64.go b/pkg/sentry/syscalls/linux/linux64.go index 3e4d312af..ad88b1391 100644 --- a/pkg/sentry/syscalls/linux/linux64.go +++ b/pkg/sentry/syscalls/linux/linux64.go @@ -360,8 +360,7 @@ var AMD64 = &kernel.SyscallTable{ 235: Utimes, // @Syscall(Vserver, note:Not implemented by Linux) 236: syscalls.Error(syscall.ENOSYS), // Vserver, not implemented by Linux - // @Syscall(Mbind, returns:EPERM or ENOSYS, note:Returns EPERM if the process does not have cap_sys_nice; ENOSYS otherwise), TODO(b/117792295) - 237: syscalls.CapError(linux.CAP_SYS_NICE), // may require cap_sys_nice + 237: Mbind, 238: SetMempolicy, 239: GetMempolicy, // 240: @Syscall(MqOpen), TODO(b/29354921) diff --git a/pkg/sentry/syscalls/linux/sys_mempolicy.go b/pkg/sentry/syscalls/linux/sys_mempolicy.go new file mode 100644 index 000000000..652b2c206 --- /dev/null +++ b/pkg/sentry/syscalls/linux/sys_mempolicy.go @@ -0,0 +1,312 @@ +// 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 + +import ( + "fmt" + + "gvisor.googlesource.com/gvisor/pkg/abi/linux" + "gvisor.googlesource.com/gvisor/pkg/sentry/arch" + "gvisor.googlesource.com/gvisor/pkg/sentry/kernel" + "gvisor.googlesource.com/gvisor/pkg/sentry/usermem" + "gvisor.googlesource.com/gvisor/pkg/syserror" +) + +// We unconditionally report a single NUMA node. This also means that our +// "nodemask_t" is a single unsigned long (uint64). +const ( + maxNodes = 1 + allowedNodemask = (1 << maxNodes) - 1 +) + +func copyInNodemask(t *kernel.Task, addr usermem.Addr, maxnode uint32) (uint64, error) { + // "nodemask points to a bit mask of node IDs that contains up to maxnode + // bits. The bit mask size is rounded to the next multiple of + // sizeof(unsigned long), but the kernel will use bits only up to maxnode. + // A NULL value of nodemask or a maxnode value of zero specifies the empty + // set of nodes. If the value of maxnode is zero, the nodemask argument is + // ignored." - set_mempolicy(2). Unfortunately, most of this is inaccurate + // because of what appears to be a bug: mm/mempolicy.c:get_nodes() uses + // maxnode-1, not maxnode, as the number of bits. + bits := maxnode - 1 + if bits > usermem.PageSize*8 { // also handles overflow from maxnode == 0 + return 0, syserror.EINVAL + } + if bits == 0 { + return 0, nil + } + // Copy in the whole nodemask. + numUint64 := (bits + 63) / 64 + buf := t.CopyScratchBuffer(int(numUint64) * 8) + if _, err := t.CopyInBytes(addr, buf); err != nil { + return 0, err + } + val := usermem.ByteOrder.Uint64(buf) + // Check that only allowed bits in the first unsigned long in the nodemask + // are set. + if val&^allowedNodemask != 0 { + return 0, syserror.EINVAL + } + // Check that all remaining bits in the nodemask are 0. + for i := 8; i < len(buf); i++ { + if buf[i] != 0 { + return 0, syserror.EINVAL + } + } + return val, nil +} + +func copyOutNodemask(t *kernel.Task, addr usermem.Addr, maxnode uint32, val uint64) error { + // mm/mempolicy.c:copy_nodes_to_user() also uses maxnode-1 as the number of + // bits. + bits := maxnode - 1 + if bits > usermem.PageSize*8 { // also handles overflow from maxnode == 0 + return syserror.EINVAL + } + if bits == 0 { + return nil + } + // Copy out the first unsigned long in the nodemask. + buf := t.CopyScratchBuffer(8) + usermem.ByteOrder.PutUint64(buf, val) + if _, err := t.CopyOutBytes(addr, buf); err != nil { + return err + } + // Zero out remaining unsigned longs in the nodemask. + if bits > 64 { + remAddr, ok := addr.AddLength(8) + if !ok { + return syserror.EFAULT + } + remUint64 := (bits - 1) / 64 + if _, err := t.MemoryManager().ZeroOut(t, remAddr, int64(remUint64)*8, usermem.IOOpts{ + AddressSpaceActive: true, + }); err != nil { + return err + } + } + return nil +} + +// GetMempolicy implements the syscall get_mempolicy(2). +func GetMempolicy(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + mode := args[0].Pointer() + nodemask := args[1].Pointer() + maxnode := args[2].Uint() + addr := args[3].Pointer() + flags := args[4].Uint() + + if flags&^(linux.MPOL_F_NODE|linux.MPOL_F_ADDR|linux.MPOL_F_MEMS_ALLOWED) != 0 { + return 0, nil, syserror.EINVAL + } + nodeFlag := flags&linux.MPOL_F_NODE != 0 + addrFlag := flags&linux.MPOL_F_ADDR != 0 + memsAllowed := flags&linux.MPOL_F_MEMS_ALLOWED != 0 + + // "EINVAL: The value specified by maxnode is less than the number of node + // IDs supported by the system." - get_mempolicy(2) + if nodemask != 0 && maxnode < maxNodes { + return 0, nil, syserror.EINVAL + } + + // "If flags specifies MPOL_F_MEMS_ALLOWED [...], the mode argument is + // ignored and the set of nodes (memories) that the thread is allowed to + // specify in subsequent calls to mbind(2) or set_mempolicy(2) (in the + // absence of any mode flags) is returned in nodemask." + if memsAllowed { + // "It is not permitted to combine MPOL_F_MEMS_ALLOWED with either + // MPOL_F_ADDR or MPOL_F_NODE." + if nodeFlag || addrFlag { + return 0, nil, syserror.EINVAL + } + if err := copyOutNodemask(t, nodemask, maxnode, allowedNodemask); err != nil { + return 0, nil, err + } + return 0, nil, nil + } + + // "If flags specifies MPOL_F_ADDR, then information is returned about the + // policy governing the memory address given in addr. ... If the mode + // argument is not NULL, then get_mempolicy() will store the policy mode + // and any optional mode flags of the requested NUMA policy in the location + // pointed to by this argument. If nodemask is not NULL, then the nodemask + // associated with the policy will be stored in the location pointed to by + // this argument." + if addrFlag { + policy, nodemaskVal, err := t.MemoryManager().NumaPolicy(addr) + if err != nil { + return 0, nil, err + } + if nodeFlag { + // "If flags specifies both MPOL_F_NODE and MPOL_F_ADDR, + // get_mempolicy() will return the node ID of the node on which the + // address addr is allocated into the location pointed to by mode. + // If no page has yet been allocated for the specified address, + // get_mempolicy() will allocate a page as if the thread had + // performed a read (load) access to that address, and return the + // ID of the node where that page was allocated." + buf := t.CopyScratchBuffer(1) + _, err := t.CopyInBytes(addr, buf) + if err != nil { + return 0, nil, err + } + policy = 0 // maxNodes == 1 + } + if mode != 0 { + if _, err := t.CopyOut(mode, policy); err != nil { + return 0, nil, err + } + } + if nodemask != 0 { + if err := copyOutNodemask(t, nodemask, maxnode, nodemaskVal); err != nil { + return 0, nil, err + } + } + return 0, nil, nil + } + + // "EINVAL: ... flags specified MPOL_F_ADDR and addr is NULL, or flags did + // not specify MPOL_F_ADDR and addr is not NULL." This is partially + // inaccurate: if flags specifies MPOL_F_ADDR, + // mm/mempolicy.c:do_get_mempolicy() doesn't special-case NULL; it will + // just (usually) fail to find a VMA at address 0 and return EFAULT. + if addr != 0 { + return 0, nil, syserror.EINVAL + } + + // "If flags is specified as 0, then information about the calling thread's + // default policy (as set by set_mempolicy(2)) is returned, in the buffers + // pointed to by mode and nodemask. ... If flags specifies MPOL_F_NODE, but + // not MPOL_F_ADDR, and the thread's current policy is MPOL_INTERLEAVE, + // then get_mempolicy() will return in the location pointed to by a + // non-NULL mode argument, the node ID of the next node that will be used + // for interleaving of internal kernel pages allocated on behalf of the + // thread." + policy, nodemaskVal := t.NumaPolicy() + if nodeFlag { + if policy&^linux.MPOL_MODE_FLAGS != linux.MPOL_INTERLEAVE { + return 0, nil, syserror.EINVAL + } + policy = 0 // maxNodes == 1 + } + if mode != 0 { + if _, err := t.CopyOut(mode, policy); err != nil { + return 0, nil, err + } + } + if nodemask != 0 { + if err := copyOutNodemask(t, nodemask, maxnode, nodemaskVal); err != nil { + return 0, nil, err + } + } + return 0, nil, nil +} + +// SetMempolicy implements the syscall set_mempolicy(2). +func SetMempolicy(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + modeWithFlags := args[0].Int() + nodemask := args[1].Pointer() + maxnode := args[2].Uint() + + modeWithFlags, nodemaskVal, err := copyInMempolicyNodemask(t, modeWithFlags, nodemask, maxnode) + if err != nil { + return 0, nil, err + } + + t.SetNumaPolicy(modeWithFlags, nodemaskVal) + return 0, nil, nil +} + +// Mbind implements the syscall mbind(2). +func Mbind(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + addr := args[0].Pointer() + length := args[1].Uint64() + mode := args[2].Int() + nodemask := args[3].Pointer() + maxnode := args[4].Uint() + flags := args[5].Uint() + + if flags&^linux.MPOL_MF_VALID != 0 { + return 0, nil, syserror.EINVAL + } + // "If MPOL_MF_MOVE_ALL is passed in flags ... [the] calling thread must be + // privileged (CAP_SYS_NICE) to use this flag." - mbind(2) + if flags&linux.MPOL_MF_MOVE_ALL != 0 && !t.HasCapability(linux.CAP_SYS_NICE) { + return 0, nil, syserror.EPERM + } + + mode, nodemaskVal, err := copyInMempolicyNodemask(t, mode, nodemask, maxnode) + if err != nil { + return 0, nil, err + } + + // Since we claim to have only a single node, all flags can be ignored + // (since all pages must already be on that single node). + err = t.MemoryManager().SetNumaPolicy(addr, length, mode, nodemaskVal) + return 0, nil, err +} + +func copyInMempolicyNodemask(t *kernel.Task, modeWithFlags int32, nodemask usermem.Addr, maxnode uint32) (int32, uint64, error) { + flags := modeWithFlags & linux.MPOL_MODE_FLAGS + mode := modeWithFlags &^ linux.MPOL_MODE_FLAGS + if flags == linux.MPOL_MODE_FLAGS { + // Can't specify both mode flags simultaneously. + return 0, 0, syserror.EINVAL + } + if mode < 0 || mode >= linux.MPOL_MAX { + // Must specify a valid mode. + return 0, 0, syserror.EINVAL + } + + var nodemaskVal uint64 + if nodemask != 0 { + var err error + nodemaskVal, err = copyInNodemask(t, nodemask, maxnode) + if err != nil { + return 0, 0, err + } + } + + switch mode { + case linux.MPOL_DEFAULT: + // "nodemask must be specified as NULL." - set_mempolicy(2). This is inaccurate; + // Linux allows a nodemask to be specified, as long as it is empty. + if nodemaskVal != 0 { + return 0, 0, syserror.EINVAL + } + case linux.MPOL_BIND, linux.MPOL_INTERLEAVE: + // These require a non-empty nodemask. + if nodemaskVal == 0 { + return 0, 0, syserror.EINVAL + } + case linux.MPOL_PREFERRED: + // This permits an empty nodemask, as long as no flags are set. + if nodemaskVal == 0 && flags != 0 { + return 0, 0, syserror.EINVAL + } + case linux.MPOL_LOCAL: + // This requires an empty nodemask and no flags set ... + if nodemaskVal != 0 || flags != 0 { + return 0, 0, syserror.EINVAL + } + // ... and is implemented as MPOL_PREFERRED. + mode = linux.MPOL_PREFERRED + default: + // Unknown mode, which we should have rejected above. + panic(fmt.Sprintf("unknown mode: %v", mode)) + } + + return mode | flags, nodemaskVal, nil +} diff --git a/pkg/sentry/syscalls/linux/sys_mmap.go b/pkg/sentry/syscalls/linux/sys_mmap.go index 64a6e639c..9926f0ac5 100644 --- a/pkg/sentry/syscalls/linux/sys_mmap.go +++ b/pkg/sentry/syscalls/linux/sys_mmap.go @@ -204,151 +204,6 @@ func Madvise(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Sysca } } -func copyOutIfNotNull(t *kernel.Task, ptr usermem.Addr, val interface{}) (int, error) { - if ptr != 0 { - return t.CopyOut(ptr, val) - } - return 0, nil -} - -// GetMempolicy implements the syscall get_mempolicy(2). -func GetMempolicy(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { - mode := args[0].Pointer() - nodemask := args[1].Pointer() - maxnode := args[2].Uint() - addr := args[3].Pointer() - flags := args[4].Uint() - - memsAllowed := flags&linux.MPOL_F_MEMS_ALLOWED != 0 - nodeFlag := flags&linux.MPOL_F_NODE != 0 - addrFlag := flags&linux.MPOL_F_ADDR != 0 - - // TODO(rahat): Once sysfs is implemented, report a single numa node in - // /sys/devices/system/node. - if nodemask != 0 && maxnode < 1 { - return 0, nil, syserror.EINVAL - } - - // 'addr' provided iff 'addrFlag' set. - if addrFlag == (addr == 0) { - return 0, nil, syserror.EINVAL - } - - // Default policy for the thread. - if flags == 0 { - policy, nodemaskVal := t.NumaPolicy() - if _, err := copyOutIfNotNull(t, mode, policy); err != nil { - return 0, nil, syserror.EFAULT - } - if _, err := copyOutIfNotNull(t, nodemask, nodemaskVal); err != nil { - return 0, nil, syserror.EFAULT - } - return 0, nil, nil - } - - // Report all nodes available to caller. - if memsAllowed { - // MPOL_F_NODE and MPOL_F_ADDR not allowed with MPOL_F_MEMS_ALLOWED. - if nodeFlag || addrFlag { - return 0, nil, syserror.EINVAL - } - - // Report a single numa node. - if _, err := copyOutIfNotNull(t, nodemask, uint32(0x1)); err != nil { - return 0, nil, syserror.EFAULT - } - return 0, nil, nil - } - - if addrFlag { - if nodeFlag { - // Return the id for the node where 'addr' resides, via 'mode'. - // - // The real get_mempolicy(2) allocates the page referenced by 'addr' - // by simulating a read, if it is unallocated before the call. It - // then returns the node the page is allocated on through the mode - // pointer. - b := t.CopyScratchBuffer(1) - _, err := t.CopyInBytes(addr, b) - if err != nil { - return 0, nil, syserror.EFAULT - } - if _, err := copyOutIfNotNull(t, mode, int32(0)); err != nil { - return 0, nil, syserror.EFAULT - } - } else { - storedPolicy, _ := t.NumaPolicy() - // Return the policy governing the memory referenced by 'addr'. - if _, err := copyOutIfNotNull(t, mode, int32(storedPolicy)); err != nil { - return 0, nil, syserror.EFAULT - } - } - return 0, nil, nil - } - - storedPolicy, _ := t.NumaPolicy() - if nodeFlag && (storedPolicy&^linux.MPOL_MODE_FLAGS == linux.MPOL_INTERLEAVE) { - // Policy for current thread is to interleave memory between - // nodes. Return the next node we'll allocate on. Since we only have a - // single node, this is always node 0. - if _, err := copyOutIfNotNull(t, mode, int32(0)); err != nil { - return 0, nil, syserror.EFAULT - } - return 0, nil, nil - } - - return 0, nil, syserror.EINVAL -} - -func allowedNodesMask() uint32 { - const maxNodes = 1 - return ^uint32((1 << maxNodes) - 1) -} - -// SetMempolicy implements the syscall set_mempolicy(2). -func SetMempolicy(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { - modeWithFlags := args[0].Int() - nodemask := args[1].Pointer() - maxnode := args[2].Uint() - - if nodemask != 0 && maxnode < 1 { - return 0, nil, syserror.EINVAL - } - - if modeWithFlags&linux.MPOL_MODE_FLAGS == linux.MPOL_MODE_FLAGS { - // Can't specify multiple modes simultaneously. - return 0, nil, syserror.EINVAL - } - - mode := modeWithFlags &^ linux.MPOL_MODE_FLAGS - if mode < 0 || mode >= linux.MPOL_MAX { - // Must specify a valid mode. - return 0, nil, syserror.EINVAL - } - - var nodemaskVal uint32 - // Nodemask may be empty for some policy modes. - if nodemask != 0 && maxnode > 0 { - if _, err := t.CopyIn(nodemask, &nodemaskVal); err != nil { - return 0, nil, syserror.EFAULT - } - } - - if (mode == linux.MPOL_INTERLEAVE || mode == linux.MPOL_BIND) && nodemaskVal == 0 { - // Mode requires a non-empty nodemask, but got an empty nodemask. - return 0, nil, syserror.EINVAL - } - - if nodemaskVal&allowedNodesMask() != 0 { - // Invalid node specified. - return 0, nil, syserror.EINVAL - } - - t.SetNumaPolicy(int32(modeWithFlags), nodemaskVal) - - return 0, nil, nil -} - // Mincore implements the syscall mincore(2). func Mincore(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { addr := args[0].Pointer() |