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[xen staging] mm: fix public declaration of struct xen_mem_acquire_resource

commit 0e2e54966af556f4047c1048855c4a071028a32d
Author:     Roger Pau Monné <roger.pau@xxxxxxxxxx>
AuthorDate: Mon Jun 29 18:03:49 2020 +0200
Commit:     Jan Beulich <jbeulich@xxxxxxxx>
CommitDate: Mon Jun 29 18:03:49 2020 +0200

    mm: fix public declaration of struct xen_mem_acquire_resource
    XENMEM_acquire_resource and it's related structure is currently inside
    a __XEN__ or __XEN_TOOLS__ guarded section to limit it's scope to the
    hypervisor or the toolstack only. This is wrong as the hypercall is
    already being used by the Linux kernel at least, and as such needs to
    be public.
    Also switch the usage of uint64_aligned_t to plain uint64_t, as
    uint64_aligned_t is only to be used by the toolstack. Doing such
    change will reduce the size of the structure on 32bit x86 by 4bytes,
    since there will be no padding added after the frame_list handle.
    This is fine, as users of the previous layout will allocate 4bytes of
    padding that won't be read by Xen, and users of the new layout won't
    allocate those, which is also fine since Xen won't try to access them.
    Note that the structure already has compat handling, and such handling
    will take care of copying the right size (ie: minus the padding) when
    called from a 32bit x86 context. This is true for the compat code both
    before and after this patch, since the structures in the memory.h
    compat header are subject to a pragma pack(4), which already removed
    the trailing padding that would otherwise be introduced by the
    alignment of the frame field to 8 bytes.
    Fixes: 3f8f12281dd20 ('x86/mm: add HYPERVISOR_memory_op to acquire guest 
    Signed-off-by: Roger Pau Monné <roger.pau@xxxxxxxxxx>
    Reviewed-by: Jan Beulich <jbeulich@xxxxxxxx>
    Release-acked-by: Paul Durrant <paul@xxxxxxx>
 xen/include/public/memory.h | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/xen/include/public/memory.h b/xen/include/public/memory.h
index 850bd72c52..21057ed78e 100644
--- a/xen/include/public/memory.h
+++ b/xen/include/public/memory.h
@@ -610,6 +610,8 @@ struct xen_reserved_device_memory_map {
 typedef struct xen_reserved_device_memory_map xen_reserved_device_memory_map_t;
+#endif /* defined(__XEN__) || defined(__XEN_TOOLS__) */
  * Get the pages for a particular guest resource, so that they can be
  * mapped directly by a tools domain.
@@ -648,7 +650,7 @@ struct xen_mem_acquire_resource {
      * IN - the index of the initial frame to be mapped. This parameter
      *      is ignored if nr_frames is 0.
-    uint64_aligned_t frame;
+    uint64_t frame;
 #define XENMEM_resource_ioreq_server_frame_bufioreq 0
 #define XENMEM_resource_ioreq_server_frame_ioreq(n) (1 + (n))
@@ -669,8 +671,6 @@ struct xen_mem_acquire_resource {
 typedef struct xen_mem_acquire_resource xen_mem_acquire_resource_t;
-#endif /* defined(__XEN__) || defined(__XEN_TOOLS__) */
  * XENMEM_get_vnumainfo used by guest to get
  * vNUMA topology from hypervisor.
generated by git-patchbot for /home/xen/git/xen.git#staging



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