diff options
| -rw-r--r-- | pkg/sentry/platform/kvm/address_space.go | 29 | ||||
| -rw-r--r-- | pkg/sentry/platform/ring0/pagetables/pagetables.go | 8 |
2 files changed, 24 insertions, 13 deletions
diff --git a/pkg/sentry/platform/kvm/address_space.go b/pkg/sentry/platform/kvm/address_space.go index a777533c5..4c76883ad 100644 --- a/pkg/sentry/platform/kvm/address_space.go +++ b/pkg/sentry/platform/kvm/address_space.go @@ -16,6 +16,7 @@ package kvm import ( "reflect" + "sync" "gvisor.googlesource.com/gvisor/pkg/sentry/platform" "gvisor.googlesource.com/gvisor/pkg/sentry/platform/filemem" @@ -27,6 +28,11 @@ import ( type addressSpace struct { platform.NoAddressSpaceIO + // mu is the lock for modifications to the address space. + // + // Note that the page tables themselves are not locked. + mu sync.Mutex + // filemem is the memory instance. filemem *filemem.FileMem @@ -49,8 +55,8 @@ type addressSpace struct { files hostMap } -// Invalidate interrupts all dirty contexts. -func (as *addressSpace) Invalidate() { +// invalidate is the implementation for Invalidate. +func (as *addressSpace) invalidate() { for i := 0; i < as.dirtySet.size(); i++ { if c := as.dirtySet.swap(i, nil); c != nil && c.active.get() == as { c.BounceToKernel() // Force a kernel transition. @@ -58,6 +64,13 @@ func (as *addressSpace) Invalidate() { } } +// Invalidate interrupts all dirty contexts. +func (as *addressSpace) Invalidate() { + as.mu.Lock() + defer as.mu.Unlock() + as.invalidate() +} + // Touch adds the given vCPU to the dirty list. // // The return value indicates whether a flush is required. @@ -120,7 +133,7 @@ func (as *addressSpace) mapHostFile(addr usermem.Addr, fd int, fr platform.FileR addr += usermem.Addr(m.length) } if inv { - as.Invalidate() + as.invalidate() } return nil @@ -169,7 +182,7 @@ func (as *addressSpace) mapFilemem(addr usermem.Addr, fr platform.FileRange, at addr += usermem.Addr(len(s)) } if inv { - as.Invalidate() + as.invalidate() as.files.DeleteMapping(orig) } @@ -178,6 +191,9 @@ func (as *addressSpace) mapFilemem(addr usermem.Addr, fr platform.FileRange, at // MapFile implements platform.AddressSpace.MapFile. func (as *addressSpace) MapFile(addr usermem.Addr, fd int, fr platform.FileRange, at usermem.AccessType, precommit bool) error { + as.mu.Lock() + defer as.mu.Unlock() + // Create an appropriate mapping. If this is filemem, we don't create // custom mappings for each in-application mapping. For files however, // we create distinct mappings for each address space. Unfortunately, @@ -195,8 +211,11 @@ func (as *addressSpace) MapFile(addr usermem.Addr, fd int, fr platform.FileRange // Unmap unmaps the given range by calling pagetables.PageTables.Unmap. func (as *addressSpace) Unmap(addr usermem.Addr, length uint64) { + as.mu.Lock() + defer as.mu.Unlock() + if prev := as.pageTables.Unmap(addr, uintptr(length)); prev { - as.Invalidate() + as.invalidate() as.files.DeleteMapping(usermem.AddrRange{ Start: addr, End: addr + usermem.Addr(length), diff --git a/pkg/sentry/platform/ring0/pagetables/pagetables.go b/pkg/sentry/platform/ring0/pagetables/pagetables.go index 2df6792f7..2a83bbff2 100644 --- a/pkg/sentry/platform/ring0/pagetables/pagetables.go +++ b/pkg/sentry/platform/ring0/pagetables/pagetables.go @@ -16,8 +16,6 @@ package pagetables import ( - "sync" - "gvisor.googlesource.com/gvisor/pkg/sentry/usermem" ) @@ -39,8 +37,6 @@ type Node struct { // PageTables is a set of page tables. type PageTables struct { - mu sync.Mutex - // root is the pagetable root. root *Node @@ -122,7 +118,6 @@ func (p *PageTables) Map(addr usermem.Addr, length uintptr, opts MapOpts, physic return p.Unmap(addr, length) } prev := false - p.mu.Lock() end, ok := addr.AddLength(uint64(length)) if !ok { panic("pagetables.Map: overflow") @@ -139,7 +134,6 @@ func (p *PageTables) Map(addr usermem.Addr, length uintptr, opts MapOpts, physic } pte.Set(p, opts) }) - p.mu.Unlock() return prev } @@ -147,13 +141,11 @@ func (p *PageTables) Map(addr usermem.Addr, length uintptr, opts MapOpts, physic // // True is returned iff there was a previous mapping in the range. func (p *PageTables) Unmap(addr usermem.Addr, length uintptr) bool { - p.mu.Lock() count := 0 p.iterateRange(uintptr(addr), uintptr(addr)+length, false, func(s, e uintptr, pte *PTE, align uintptr) { pte.Clear() count++ }) - p.mu.Unlock() return count > 0 } |