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Diffstat (limited to 'include/hw/virtio/dataplane/hostmem.h')
-rw-r--r-- | include/hw/virtio/dataplane/hostmem.h | 57 |
1 files changed, 57 insertions, 0 deletions
diff --git a/include/hw/virtio/dataplane/hostmem.h b/include/hw/virtio/dataplane/hostmem.h new file mode 100644 index 0000000..b2cf093 --- /dev/null +++ b/include/hw/virtio/dataplane/hostmem.h @@ -0,0 +1,57 @@ +/* + * Thread-safe guest to host memory mapping + * + * Copyright 2012 Red Hat, Inc. and/or its affiliates + * + * Authors: + * Stefan Hajnoczi <stefanha@redhat.com> + * + * This work is licensed under the terms of the GNU GPL, version 2 or later. + * See the COPYING file in the top-level directory. + * + */ + +#ifndef HOSTMEM_H +#define HOSTMEM_H + +#include "exec/memory.h" +#include "qemu/thread.h" + +typedef struct { + void *host_addr; + hwaddr guest_addr; + uint64_t size; + bool readonly; +} HostMemRegion; + +typedef struct { + /* The listener is invoked when regions change and a new list of regions is + * built up completely before they are installed. + */ + MemoryListener listener; + HostMemRegion *new_regions; + size_t num_new_regions; + + /* Current regions are accessed from multiple threads either to lookup + * addresses or to install a new list of regions. The lock protects the + * pointer and the regions. + */ + QemuMutex current_regions_lock; + HostMemRegion *current_regions; + size_t num_current_regions; +} HostMem; + +void hostmem_init(HostMem *hostmem); +void hostmem_finalize(HostMem *hostmem); + +/** + * Map a guest physical address to a pointer + * + * Note that there is map/unmap mechanism here. The caller must ensure that + * mapped memory is no longer used across events like hot memory unplug. This + * can be done with other mechanisms like bdrv_drain_all() that quiesce + * in-flight I/O. + */ +void *hostmem_lookup(HostMem *hostmem, hwaddr phys, hwaddr len, bool is_write); + +#endif /* HOSTMEM_H */ |