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Diffstat (limited to 'include/hw/xen/xen_backend_ops.h')
| -rw-r--r-- | include/hw/xen/xen_backend_ops.h | 408 |
1 files changed, 408 insertions, 0 deletions
diff --git a/include/hw/xen/xen_backend_ops.h b/include/hw/xen/xen_backend_ops.h new file mode 100644 index 0000000000..90cca85f52 --- /dev/null +++ b/include/hw/xen/xen_backend_ops.h @@ -0,0 +1,408 @@ +/* + * QEMU Xen backend support + * + * Copyright © 2022 Amazon.com, Inc. or its affiliates. All Rights Reserved. + * + * Authors: David Woodhouse <dwmw2@infradead.org> + * + * 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 QEMU_XEN_BACKEND_OPS_H +#define QEMU_XEN_BACKEND_OPS_H + +#include "hw/xen/xen.h" +#include "hw/xen/interface/xen.h" +#include "hw/xen/interface/io/xenbus.h" + +/* + * For the time being, these operations map fairly closely to the API of + * the actual Xen libraries, e.g. libxenevtchn. As we complete the migration + * from XenLegacyDevice back ends to the new XenDevice model, they may + * evolve to slightly higher-level APIs. + * + * The internal emulations do not emulate the Xen APIs entirely faithfully; + * only enough to be used by the Xen backend devices. For example, only one + * event channel can be bound to each handle, since that's sufficient for + * the device support (only the true Xen HVM backend uses more). And the + * behaviour of unmask() and pending() is different too because the device + * backends don't care. + */ + +typedef struct xenevtchn_handle xenevtchn_handle; +typedef int xenevtchn_port_or_error_t; +typedef uint32_t evtchn_port_t; +typedef uint16_t domid_t; +typedef uint32_t grant_ref_t; + +#define XEN_PAGE_SHIFT 12 +#define XEN_PAGE_SIZE (1UL << XEN_PAGE_SHIFT) +#define XEN_PAGE_MASK (~(XEN_PAGE_SIZE - 1)) + +#ifndef xen_rmb +#define xen_rmb() smp_rmb() +#endif +#ifndef xen_wmb +#define xen_wmb() smp_wmb() +#endif +#ifndef xen_mb +#define xen_mb() smp_mb() +#endif + +struct evtchn_backend_ops { + xenevtchn_handle *(*open)(void); + int (*bind_interdomain)(xenevtchn_handle *xc, uint32_t domid, + evtchn_port_t guest_port); + int (*unbind)(xenevtchn_handle *xc, evtchn_port_t port); + int (*close)(struct xenevtchn_handle *xc); + int (*get_fd)(struct xenevtchn_handle *xc); + int (*notify)(struct xenevtchn_handle *xc, evtchn_port_t port); + int (*unmask)(struct xenevtchn_handle *xc, evtchn_port_t port); + int (*pending)(struct xenevtchn_handle *xc); +}; + +extern struct evtchn_backend_ops *xen_evtchn_ops; + +static inline xenevtchn_handle *qemu_xen_evtchn_open(void) +{ + if (!xen_evtchn_ops) { + return NULL; + } + return xen_evtchn_ops->open(); +} + +static inline int qemu_xen_evtchn_bind_interdomain(xenevtchn_handle *xc, + uint32_t domid, + evtchn_port_t guest_port) +{ + if (!xen_evtchn_ops) { + return -ENOSYS; + } + return xen_evtchn_ops->bind_interdomain(xc, domid, guest_port); +} + +static inline int qemu_xen_evtchn_unbind(xenevtchn_handle *xc, + evtchn_port_t port) +{ + if (!xen_evtchn_ops) { + return -ENOSYS; + } + return xen_evtchn_ops->unbind(xc, port); +} + +static inline int qemu_xen_evtchn_close(xenevtchn_handle *xc) +{ + if (!xen_evtchn_ops) { + return -ENOSYS; + } + return xen_evtchn_ops->close(xc); +} + +static inline int qemu_xen_evtchn_fd(xenevtchn_handle *xc) +{ + if (!xen_evtchn_ops) { + return -ENOSYS; + } + return xen_evtchn_ops->get_fd(xc); +} + +static inline int qemu_xen_evtchn_notify(xenevtchn_handle *xc, + evtchn_port_t port) +{ + if (!xen_evtchn_ops) { + return -ENOSYS; + } + return xen_evtchn_ops->notify(xc, port); +} + +static inline int qemu_xen_evtchn_unmask(xenevtchn_handle *xc, + evtchn_port_t port) +{ + if (!xen_evtchn_ops) { + return -ENOSYS; + } + return xen_evtchn_ops->unmask(xc, port); +} + +static inline int qemu_xen_evtchn_pending(xenevtchn_handle *xc) +{ + if (!xen_evtchn_ops) { + return -ENOSYS; + } + return xen_evtchn_ops->pending(xc); +} + +typedef struct xengntdev_handle xengnttab_handle; + +typedef struct XenGrantCopySegment { + union { + void *virt; + struct { + uint32_t ref; + off_t offset; + } foreign; + } source, dest; + size_t len; +} XenGrantCopySegment; + +#define XEN_GNTTAB_OP_FEATURE_MAP_MULTIPLE (1U << 0) + +struct gnttab_backend_ops { + uint32_t features; + xengnttab_handle *(*open)(void); + int (*close)(xengnttab_handle *xgt); + int (*grant_copy)(xengnttab_handle *xgt, bool to_domain, uint32_t domid, + XenGrantCopySegment *segs, uint32_t nr_segs, + Error **errp); + int (*set_max_grants)(xengnttab_handle *xgt, uint32_t nr_grants); + void *(*map_refs)(xengnttab_handle *xgt, uint32_t count, uint32_t domid, + uint32_t *refs, int prot); + int (*unmap)(xengnttab_handle *xgt, void *start_address, uint32_t *refs, + uint32_t count); +}; + +extern struct gnttab_backend_ops *xen_gnttab_ops; + +static inline bool qemu_xen_gnttab_can_map_multi(void) +{ + return xen_gnttab_ops && + !!(xen_gnttab_ops->features & XEN_GNTTAB_OP_FEATURE_MAP_MULTIPLE); +} + +static inline xengnttab_handle *qemu_xen_gnttab_open(void) +{ + if (!xen_gnttab_ops) { + return NULL; + } + return xen_gnttab_ops->open(); +} + +static inline int qemu_xen_gnttab_close(xengnttab_handle *xgt) +{ + if (!xen_gnttab_ops) { + return -ENOSYS; + } + return xen_gnttab_ops->close(xgt); +} + +static inline int qemu_xen_gnttab_grant_copy(xengnttab_handle *xgt, + bool to_domain, uint32_t domid, + XenGrantCopySegment *segs, + uint32_t nr_segs, Error **errp) +{ + if (!xen_gnttab_ops) { + return -ENOSYS; + } + + return xen_gnttab_ops->grant_copy(xgt, to_domain, domid, segs, nr_segs, + errp); +} + +static inline int qemu_xen_gnttab_set_max_grants(xengnttab_handle *xgt, + uint32_t nr_grants) +{ + if (!xen_gnttab_ops) { + return -ENOSYS; + } + return xen_gnttab_ops->set_max_grants(xgt, nr_grants); +} + +static inline void *qemu_xen_gnttab_map_refs(xengnttab_handle *xgt, + uint32_t count, uint32_t domid, + uint32_t *refs, int prot) +{ + if (!xen_gnttab_ops) { + return NULL; + } + return xen_gnttab_ops->map_refs(xgt, count, domid, refs, prot); +} + +static inline int qemu_xen_gnttab_unmap(xengnttab_handle *xgt, + void *start_address, uint32_t *refs, + uint32_t count) +{ + if (!xen_gnttab_ops) { + return -ENOSYS; + } + return xen_gnttab_ops->unmap(xgt, start_address, refs, count); +} + +struct foreignmem_backend_ops { + void *(*map)(uint32_t dom, void *addr, int prot, size_t pages, + xen_pfn_t *pfns, int *errs); + int (*unmap)(void *addr, size_t pages); +}; + +extern struct foreignmem_backend_ops *xen_foreignmem_ops; + +static inline void *qemu_xen_foreignmem_map(uint32_t dom, void *addr, int prot, + size_t pages, xen_pfn_t *pfns, + int *errs) +{ + if (!xen_foreignmem_ops) { + return NULL; + } + return xen_foreignmem_ops->map(dom, addr, prot, pages, pfns, errs); +} + +static inline int qemu_xen_foreignmem_unmap(void *addr, size_t pages) +{ + if (!xen_foreignmem_ops) { + return -ENOSYS; + } + return xen_foreignmem_ops->unmap(addr, pages); +} + +typedef void (*xs_watch_fn)(void *opaque, const char *path); + +struct qemu_xs_handle; +struct qemu_xs_watch; +typedef uint32_t xs_transaction_t; + +#define XBT_NULL 0 + +#define XS_PERM_NONE 0x00 +#define XS_PERM_READ 0x01 +#define XS_PERM_WRITE 0x02 + +struct xenstore_backend_ops { + struct qemu_xs_handle *(*open)(void); + void (*close)(struct qemu_xs_handle *h); + char *(*get_domain_path)(struct qemu_xs_handle *h, unsigned int domid); + char **(*directory)(struct qemu_xs_handle *h, xs_transaction_t t, + const char *path, unsigned int *num); + void *(*read)(struct qemu_xs_handle *h, xs_transaction_t t, + const char *path, unsigned int *len); + bool (*write)(struct qemu_xs_handle *h, xs_transaction_t t, + const char *path, const void *data, unsigned int len); + bool (*create)(struct qemu_xs_handle *h, xs_transaction_t t, + unsigned int owner, unsigned int domid, + unsigned int perms, const char *path); + bool (*destroy)(struct qemu_xs_handle *h, xs_transaction_t t, + const char *path); + struct qemu_xs_watch *(*watch)(struct qemu_xs_handle *h, const char *path, + xs_watch_fn fn, void *opaque); + void (*unwatch)(struct qemu_xs_handle *h, struct qemu_xs_watch *w); + xs_transaction_t (*transaction_start)(struct qemu_xs_handle *h); + bool (*transaction_end)(struct qemu_xs_handle *h, xs_transaction_t t, + bool abort); +}; + +extern struct xenstore_backend_ops *xen_xenstore_ops; + +static inline struct qemu_xs_handle *qemu_xen_xs_open(void) +{ + if (!xen_xenstore_ops) { + return NULL; + } + return xen_xenstore_ops->open(); +} + +static inline void qemu_xen_xs_close(struct qemu_xs_handle *h) +{ + if (!xen_xenstore_ops) { + return; + } + xen_xenstore_ops->close(h); +} + +static inline char *qemu_xen_xs_get_domain_path(struct qemu_xs_handle *h, + unsigned int domid) +{ + if (!xen_xenstore_ops) { + return NULL; + } + return xen_xenstore_ops->get_domain_path(h, domid); +} + +static inline char **qemu_xen_xs_directory(struct qemu_xs_handle *h, + xs_transaction_t t, const char *path, + unsigned int *num) +{ + if (!xen_xenstore_ops) { + return NULL; + } + return xen_xenstore_ops->directory(h, t, path, num); +} + +static inline void *qemu_xen_xs_read(struct qemu_xs_handle *h, + xs_transaction_t t, const char *path, + unsigned int *len) +{ + if (!xen_xenstore_ops) { + return NULL; + } + return xen_xenstore_ops->read(h, t, path, len); +} + +static inline bool qemu_xen_xs_write(struct qemu_xs_handle *h, + xs_transaction_t t, const char *path, + const void *data, unsigned int len) +{ + if (!xen_xenstore_ops) { + return false; + } + return xen_xenstore_ops->write(h, t, path, data, len); +} + +static inline bool qemu_xen_xs_create(struct qemu_xs_handle *h, + xs_transaction_t t, unsigned int owner, + unsigned int domid, unsigned int perms, + const char *path) +{ + if (!xen_xenstore_ops) { + return false; + } + return xen_xenstore_ops->create(h, t, owner, domid, perms, path); +} + +static inline bool qemu_xen_xs_destroy(struct qemu_xs_handle *h, + xs_transaction_t t, const char *path) +{ + if (!xen_xenstore_ops) { + return false; + } + return xen_xenstore_ops->destroy(h, t, path); +} + +static inline struct qemu_xs_watch *qemu_xen_xs_watch(struct qemu_xs_handle *h, + const char *path, + xs_watch_fn fn, + void *opaque) +{ + if (!xen_xenstore_ops) { + return NULL; + } + return xen_xenstore_ops->watch(h, path, fn, opaque); +} + +static inline void qemu_xen_xs_unwatch(struct qemu_xs_handle *h, + struct qemu_xs_watch *w) +{ + if (!xen_xenstore_ops) { + return; + } + xen_xenstore_ops->unwatch(h, w); +} + +static inline xs_transaction_t qemu_xen_xs_transaction_start(struct qemu_xs_handle *h) +{ + if (!xen_xenstore_ops) { + return XBT_NULL; + } + return xen_xenstore_ops->transaction_start(h); +} + +static inline bool qemu_xen_xs_transaction_end(struct qemu_xs_handle *h, + xs_transaction_t t, bool abort) +{ + if (!xen_xenstore_ops) { + return false; + } + return xen_xenstore_ops->transaction_end(h, t, abort); +} + +void setup_xen_backend_ops(void); + +#endif /* QEMU_XEN_BACKEND_OPS_H */ |