linux-toradex.git/include/xen/grant_table.h, branch v3.4.10

xen/grant-table: Support mappings required by blkback

2011-12-20T22:07:27+00:00

Add support for mappings without GNTMAP_contains_pte. This was not
supported because the unmap operation assumed that this flag was being
used; adding a parameter to the unmap operation to allow the PTE
clearing to be disabled is sufficient to make unmap capable of
supporting either mapping type.

Signed-off-by: Daniel De Graaf 
[v1: Fix cleanpatch warnings]
Signed-off-by: Konrad Rzeszutek Wilk

xen/granttable: Support transitive grants

2011-12-16T16:25:39+00:00

These allow a domain A which has been granted access on a page of domain B's
memory to issue domain C with a copy-grant on the same page.  This is useful
e.g. for forwarding packets between domains.

Signed-off-by: Annie Li 
Signed-off-by: Konrad Rzeszutek Wilk

xen/granttable: Support sub-page grants

2011-12-16T16:25:02+00:00

- They can't be used to map the page (so can only be used in a GNTTABOP_copy
  hypercall).
- It's possible to grant access with a finer granularity than whole pages.
- Xen guarantees that they can be revoked quickly (a normal map grant can
  only be revoked with the cooperation of the domain which has been granted
  access).

Signed-off-by: Annie Li 
Signed-off-by: Konrad Rzeszutek Wilk

xen/granttable: Keep code format clean

2011-11-22T14:26:20+00:00

Acked-by: Ian Campbell 
Signed-off-by: Annie Li 
Signed-off-by: Konrad Rzeszutek Wilk

xen/granttable: Grant tables V2 implementation

2011-11-22T14:24:51+00:00

Receiver-side copying of packets is based on this implementation, it gives
better performance and better CPU accounting. It totally supports three types:
full-page, sub-page and transitive grants.

However this patch does not cover sub-page and transitive grants, it mainly
focus on Full-page part and implements grant table V2 interfaces corresponding
to what already exists in grant table V1, such as: grant table V2
initialization, mapping, releasing and exported interfaces.

Each guest can only supports one type of grant table type, every entry in grant
table should be the same version. It is necessary to set V1 or V2 version before
initializing the grant table.

Grant table exported interfaces of V2 are same with those of V1, Xen is
responsible to judge what grant table version guests are using in every grant
operation.

V2 fulfills the same role of V1, and it is totally backwards compitable with V1.
If dom0 support grant table V2, the guests runing on it can run with either V1
or V2.

Acked-by: Ian Campbell 
Signed-off-by: Annie Li 
[v1: Modified alloc_vm_area call (new parameters), indentation, and cleanpatch
     warnings]
Signed-off-by: Konrad Rzeszutek Wilk

xen/granttable: Introducing grant table V2 stucture

2011-11-22T14:23:44+00:00

This patch introduces new structures of grant table V2, grant table V2 is an
extension from V1. Grant table is shared between guest and Xen, and Xen is
responsible to do corresponding work for grant operations, such as: figure
out guest's grant table version, perform different actions based on
different grant table version, etc. Although full-page structure of V2
is different from V1, it play the same role as V1.

Acked-by: Ian Campbell 
Signed-off-by: Annie Li 
Signed-off-by: Konrad Rzeszutek Wilk

Merge branch 'stable/vmalloc-3.2' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen

2011-11-07T02:31:36+00:00

* 'stable/vmalloc-3.2' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
  net: xen-netback: use API provided by xenbus module to map rings
  block: xen-blkback: use API provided by xenbus module to map rings
  xen: use generic functions instead of xen_{alloc, free}_vm_area()

xen: use generic functions instead of xen_{alloc, free}_vm_area()

2011-09-29T19:02:18+00:00

Replace calls to the Xen-specific xen_alloc_vm_area() and
xen_free_vm_area() functions with the generic equivalent
(alloc_vm_area() and free_vm_area()).

On x86, these were identical already.

Signed-off-by: David Vrabel 
Signed-off-by: Konrad Rzeszutek Wilk

xen: modify kernel mappings corresponding to granted pages

2011-09-29T14:32:58+00:00

If we want to use granted pages for AIO, changing the mappings of a user
vma and the corresponding p2m is not enough, we also need to update the
kernel mappings accordingly.
Currently this is only needed for pages that are created for user usages
through /dev/xen/gntdev. As in, pages that have been in use by the
kernel and use the P2M will not need this special mapping.
However there are no guarantees that in the future the kernel won't
start accessing pages through the 1:1 even for internal usage.

In order to avoid the complexity of dealing with highmem, we allocated
the pages lowmem.
We issue a HYPERVISOR_grant_table_op right away in
m2p_add_override and we remove the mappings using another
HYPERVISOR_grant_table_op in m2p_remove_override.
Considering that m2p_add_override and m2p_remove_override are called
once per page we use multicalls and hypercall batching.

Use the kmap_op pointer directly as argument to do the mapping as it is
guaranteed to be present up until the unmapping is done.
Before issuing any unmapping multicalls, we need to make sure that the
mapping has already being done, because we need the kmap->handle to be
set correctly.

Signed-off-by: Stefano Stabellini 
[v1: Removed GRANT_FRAME_BIT usage]
Signed-off-by: Konrad Rzeszutek Wilk

xen: introduce gnttab_map_refs and gnttab_unmap_refs

2011-01-11T19:32:00+00:00

gnttab_map_refs maps some grant refs and uses the new m2p override to
set a proper m2p mapping for the granted pages.

gnttab_unmap_refs unmaps the granted refs and removes th mappings from
the m2p override.

Signed-off-by: Stefano Stabellini 
Signed-off-by: Jeremy Fitzhardinge 
Signed-off-by: Konrad Rzeszutek Wilk