@@ -7,6 +7,7 @@ CFLAGS += -include $(XEN_ROOT)/tools/config.h
CFLAGS-$(CONFIG_SYSTEMD) += $(SYSTEMD_CFLAGS)
LDFLAGS-$(CONFIG_SYSTEMD) += $(SYSTEMD_LIBS)
+CFLAGS += $(CFLAGS_libxengnttab) -I../libs/mmap
CFLAGS += $(CFLAGS-y)
CFLAGS += $(APPEND_CFLAGS)
LDFLAGS += $(LDFLAGS-y)
@@ -18,12 +19,15 @@ OCAMLINCLUDE += \
-I $(OCAML_TOPLEVEL)/libs/xc \
-I $(OCAML_TOPLEVEL)/libs/eventchn
-LIBS = syslog.cma syslog.cmxa poll.cma poll.cmxa
+LIBS = syslog.cma syslog.cmxa poll.cma poll.cmxa gnt.cma gnt.cmxa
syslog_OBJS = syslog
syslog_C_OBJS = syslog_stubs
poll_OBJS = poll
poll_C_OBJS = select_stubs
-OCAML_LIBRARY = syslog poll
+gnt_OBJS = gnt
+gnt_C_OBJS = gnttab_stubs
+LIBS_gnt += $(LDLIBS_libxengnttab)
+OCAML_LIBRARY = syslog poll gnt
LIBS += systemd.cma systemd.cmxa
systemd_OBJS = systemd
@@ -58,7 +62,7 @@ OBJS = paths \
process \
xenstored
-INTF = symbol.cmi trie.cmi syslog.cmi systemd.cmi poll.cmi
+INTF = symbol.cmi trie.cmi syslog.cmi systemd.cmi poll.cmi gnt.cmi
XENSTOREDLIBS = \
unix.cmxa \
@@ -66,6 +70,7 @@ XENSTOREDLIBS = \
-ccopt -L -ccopt . systemd.cmxa \
-ccopt -L -ccopt . poll.cmxa \
-ccopt -L -ccopt $(OCAML_TOPLEVEL)/libs/mmap $(OCAML_TOPLEVEL)/libs/mmap/xenmmap.cmxa \
+ -ccopt -L -ccopt . gnt.cmxa \
-ccopt -L -ccopt $(OCAML_TOPLEVEL)/libs/eventchn $(OCAML_TOPLEVEL)/libs/eventchn/xeneventchn.cmxa \
-ccopt -L -ccopt $(OCAML_TOPLEVEL)/libs/xc $(OCAML_TOPLEVEL)/libs/xc/xenctrl.cmxa \
-ccopt -L -ccopt $(OCAML_TOPLEVEL)/libs/xb $(OCAML_TOPLEVEL)/libs/xb/xenbus.cmxa \
new file mode 100644
@@ -0,0 +1,60 @@
+(*
+ * Copyright (c) 2010 Anil Madhavapeddy <anil@recoil.org>
+ * Copyright (C) 2012-2014 Citrix Inc
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ *)
+
+type gntref = int
+type domid = int
+
+let console = 0 (* public/grant_table.h:GNTTAB_RESERVED_CONSOLE *)
+let xenstore = 1 (* public/grant_table.h:GNTTAB_RESERVED_XENSTORE *)
+
+type grant_handle (* handle to a mapped grant *)
+
+module Gnttab = struct
+ type interface
+
+ external interface_open': unit -> interface = "stub_gnttab_interface_open"
+
+ let interface_open () =
+ try
+ interface_open' ()
+ with e ->
+ Printf.fprintf stderr "Failed to open grant table device: ENOENT\n";
+ Printf.fprintf stderr "Does this system have Xen userspace grant table support?\n";
+ Printf.fprintf stderr "On linux try:\n";
+ Printf.fprintf stderr " sudo modprobe xen-gntdev\n%!";
+ raise e
+
+ external interface_close: interface -> unit = "stub_gnttab_interface_close"
+
+ type grant = {
+ domid: domid;
+ ref: gntref;
+ }
+
+ module Local_mapping = struct
+ type t = Xenmmap.mmap_interface
+
+ let to_pages t = t
+ end
+
+ external unmap_exn : interface -> Local_mapping.t -> unit = "stub_gnttab_unmap"
+
+ external map_fresh_exn: interface -> gntref -> domid -> bool -> Local_mapping.t = "stub_gnttab_map_fresh"
+
+ let map_exn interface grant writable =
+ map_fresh_exn interface grant.ref grant.domid writable
+end
new file mode 100644
@@ -0,0 +1,86 @@
+(*
+ * Copyright (c) 2010 Anil Madhavapeddy <anil@recoil.org>
+ * Copyright (C) 2012-2014 Citrix Inc
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ *)
+
+(** Allow a local xen domain to read/write memory exported ("granted")
+ from foreign domains. Safe memory sharing is a building block of all
+ xen inter-domain communication protocols such as those for virtual
+ network and disk devices.
+
+ Foreign domains will explicitly "grant" us access to certain memory
+ regions such as disk buffers. These regions are uniquely identified
+ by the pair of (foreign domain id, integer reference) which is
+ passed to us over some existing channel (typically via xenstore keys
+ or via structures in previously-shared memory region).
+*)
+
+(** {2 Common interface} *)
+
+type gntref = int
+(** Type of a grant table index, called a grant reference in
+ Xen's terminology. *)
+
+(** {2 Receiving foreign pages} *)
+
+module Gnttab : sig
+ type interface
+ (** A connection to the grant device, needed for mapping/unmapping *)
+
+ val interface_open: unit -> interface
+ (** Open a connection to the grant device. This must be done before any
+ calls to map or unmap. *)
+
+ val interface_close: interface -> unit
+ (** Close a connection to the grant device. Any future calls to map or
+ unmap will fail. *)
+
+ type grant = {
+ domid: int;
+ (** foreign domain who is exporting memory *)
+ ref: gntref;
+ (** id which identifies the specific export in the foreign domain *)
+ }
+ (** A foreign domain must explicitly "grant" us memory and send us the
+ "reference". The pair of (foreign domain id, reference) uniquely
+ identifies the block of memory. This pair ("grant") is transmitted
+ to us out-of-band, usually either via xenstore during device setup or
+ via a shared memory ring structure. *)
+
+ module Local_mapping : sig
+ type t
+ (** Abstract type representing a locally-mapped shared memory page *)
+
+ val to_pages: t -> Xenmmap.mmap_interface
+ end
+
+ val map_exn : interface -> grant -> bool -> Local_mapping.t
+ (** [map_exn if grant writable] creates a single mapping from
+ [grant] that will be writable if [writable] is [true]. *)
+
+ val unmap_exn: interface -> Local_mapping.t -> unit
+ (** Unmap a single mapping (which may involve multiple grants). Throws a
+ Failure if unsuccessful. *)
+end
+
+val console: gntref
+(** In xen-4.2 and later, the domain builder will allocate one of the
+ reserved grant table entries and use it to pre-authorise the console
+ backend domain. *)
+
+val xenstore: gntref
+(** In xen-4.2 and later, the domain builder will allocate one of the
+ reserved grant table entries and use it to pre-authorise the xenstore
+ backend domain. *)
new file mode 100644
@@ -0,0 +1,106 @@
+/*
+ * Copyright (C) 2012-2013 Citrix Inc
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include <stdlib.h>
+#include <stdint.h>
+#include <string.h>
+#include <errno.h>
+
+/* For PROT_READ | PROT_WRITE */
+#include <sys/mman.h>
+
+#define CAML_NAME_SPACE
+#include <caml/alloc.h>
+#include <caml/memory.h>
+#include <caml/signals.h>
+#include <caml/fail.h>
+#include <caml/callback.h>
+#include <caml/bigarray.h>
+
+#include "xengnttab.h"
+#include "mmap_stubs.h"
+
+#ifndef Data_abstract_val
+#define Data_abstract_val(v) ((void*) Op_val(v))
+#endif
+
+#define _G(__g) (*((xengnttab_handle**)Data_abstract_val(__g)))
+
+CAMLprim value stub_gnttab_interface_open(void)
+{
+ CAMLparam0();
+ CAMLlocal1(result);
+ xengnttab_handle *xgh;
+
+ xgh = xengnttab_open(NULL, 0);
+ if (xgh == NULL)
+ caml_failwith("Failed to open interface");
+ result = caml_alloc(1, Abstract_tag);
+ _G(result) = xgh;
+
+ CAMLreturn(result);
+}
+
+CAMLprim value stub_gnttab_interface_close(value xgh)
+{
+ CAMLparam1(xgh);
+
+ xengnttab_close(_G(xgh));
+
+ CAMLreturn(Val_unit);
+}
+
+#define _M(__m) ((struct mmap_interface*)Data_abstract_val(__m))
+#define XEN_PAGE_SHIFT 12
+
+CAMLprim value stub_gnttab_unmap(value xgh, value array)
+{
+ CAMLparam2(xgh, array);
+ int result;
+
+ caml_enter_blocking_section();
+ result = xengnttab_unmap(_G(xgh), _M(array)->addr, _M(array)->len >> XEN_PAGE_SHIFT);
+ caml_leave_blocking_section();
+
+ if(result!=0) {
+ caml_failwith("Failed to unmap grant");
+ }
+
+ CAMLreturn(Val_unit);
+}
+
+CAMLprim value stub_gnttab_map_fresh(
+ value xgh,
+ value reference,
+ value domid,
+ value writable
+ )
+{
+ CAMLparam4(xgh, reference, domid, writable);
+ CAMLlocal1(contents);
+ void *map;
+
+ caml_enter_blocking_section();
+ map = xengnttab_map_grant_ref(_G(xgh), Int_val(domid), Int_val(reference),
+ Bool_val(writable)?PROT_READ | PROT_WRITE:PROT_READ);
+ caml_leave_blocking_section();
+
+ if(map==NULL) {
+ caml_failwith("Failed to map grant ref");
+ }
+ contents = stub_mmap_alloc(map, 1 << XEN_PAGE_SHIFT);
+ CAMLreturn(contents);
+}
Upstream URL: https://github.com/mirage/ocaml-gnt Mirage is part of the Xen project and the license is compatible, copyright headers are retained. Changes from upstream: * cut down dependencies: dropped Lwt, replaced Io_page with Xenmmap * only import Gnttab and not Gntshr This is for xenstored's use only which needs a way to grant map the xenstore ring without using xenctrl. Signed-off-by: Edwin Török <edvin.torok@citrix.com> --- tools/ocaml/xenstored/Makefile | 11 ++- tools/ocaml/xenstored/gnt.ml | 60 +++++++++++++++ tools/ocaml/xenstored/gnt.mli | 86 ++++++++++++++++++++++ tools/ocaml/xenstored/gnttab_stubs.c | 106 +++++++++++++++++++++++++++ 4 files changed, 260 insertions(+), 3 deletions(-) create mode 100644 tools/ocaml/xenstored/gnt.ml create mode 100644 tools/ocaml/xenstored/gnt.mli create mode 100644 tools/ocaml/xenstored/gnttab_stubs.c