This patch allows grant table frames to be mapped using the
XENMEM_acquire_resource memory op.
Signed-off-by: Paul Durrant <paul.durr...@citrix.com>
---
Cc: Andrew Cooper <andrew.coop...@citrix.com>
Cc: George Dunlap <george.dun...@eu.citrix.com>
Cc: Ian Jackson <ian.jack...@eu.citrix.com>
Cc: Jan Beulich <jbeul...@suse.com>
Cc: Konrad Rzeszutek Wilk <konrad.w...@oracle.com>
Cc: Stefano Stabellini <sstabell...@kernel.org>
Cc: Tim Deegan <t...@xen.org>
Cc: Wei Liu <wei.l...@citrix.com>
v8:
- The functionality was originally incorporated into the earlier patch
"x86/mm: add HYPERVISOR_memory_op to acquire guest resources".
---
xen/common/grant_table.c | 32 ++++++++++++++++++++++++++++----
xen/common/memory.c | 30 ++++++++++++++++++++++++++++++
xen/include/public/memory.h | 5 +++++
xen/include/xen/grant_table.h | 1 +
4 files changed, 64 insertions(+), 4 deletions(-)
diff --git a/xen/common/grant_table.c b/xen/common/grant_table.c
index 71706f5cba..0530cf63c9 100644
--- a/xen/common/grant_table.c
+++ b/xen/common/grant_table.c
@@ -3720,14 +3720,13 @@ int mem_sharing_gref_to_gfn(struct grant_table *gt,
grant_ref_t ref,
}
#endif
-int gnttab_map_frame(struct domain *d, unsigned long idx, gfn_t gfn,
- mfn_t *mfn)
+/* Caller must hold write lock as version may change and table may grow */
+static int gnttab_get_frame_locked(struct domain *d, unsigned long idx,
+ mfn_t *mfn)
{
int rc = 0;
struct grant_table *gt = d->grant_table;
- grant_write_lock(gt);
-
if ( gt->gt_version == 0 )
gt->gt_version = 1;
@@ -3751,6 +3750,19 @@ int gnttab_map_frame(struct domain *d, unsigned long
idx, gfn_t gfn,
rc = -EINVAL;
}
+ return rc;
+}
+
+int gnttab_map_frame(struct domain *d, unsigned long idx, gfn_t gfn,
+ mfn_t *mfn)
+{
+ struct grant_table *gt = d->grant_table;
+ int rc;
+
+ grant_write_lock(gt);
+
+ rc = gnttab_get_frame_locked(d, idx, mfn);
+
if ( !rc )
gnttab_set_frame_gfn(gt, idx, gfn);
@@ -3759,6 +3771,18 @@ int gnttab_map_frame(struct domain *d, unsigned long
idx, gfn_t gfn,
return rc;
}
+int gnttab_get_frame(struct domain *d, unsigned long idx, mfn_t *mfn)
+{
+ struct grant_table *gt = d->grant_table;
+ int rc;
+
+ grant_write_lock(gt); /* write lock is required as table may grow */
+ rc = gnttab_get_frame_locked(d, idx, mfn);
+ grant_write_unlock(gt);
+
+ return rc;
+}
+
static void gnttab_usage_print(struct domain *rd)
{
int first = 1;
diff --git a/xen/common/memory.c b/xen/common/memory.c
index a068877cf6..fb14f79218 100644
--- a/xen/common/memory.c
+++ b/xen/common/memory.c
@@ -23,6 +23,7 @@
#include <xen/numa.h>
#include <xen/mem_access.h>
#include <xen/trace.h>
+#include <xen/grant_table.h>
#include <asm/current.h>
#include <asm/hardirq.h>
#include <asm/p2m.h>
@@ -965,6 +966,30 @@ static long xatp_permission_check(struct domain *d,
unsigned int space)
}
#ifdef CONFIG_X86
+static int acquire_grant_table(struct domain *d, unsigned int id,
+ unsigned long frame,
+ unsigned long nr_frames,
+ unsigned long mfn_list[])
+{
+ unsigned int i = nr_frames;
+
+ if ( id != 0 )
+ return -EINVAL;
+
+ while ( i-- != 0 )
+ {
+ mfn_t mfn = INVALID_MFN;
+ int rc = gnttab_get_frame(d, frame + i, &mfn);
+
+ if ( rc )
+ return rc;
+
+ mfn_list[i] = mfn_x(mfn);
+ }
+
+ return 0;
+}
+
static int acquire_resource(const xen_mem_acquire_resource_t *xmar)
{
struct domain *d, *currd = current->domain;
@@ -992,6 +1017,11 @@ static int acquire_resource(const
xen_mem_acquire_resource_t *xmar)
xmar->nr_frames, mfn_list);
break;
+ case XENMEM_resource_grant_table:
+ rc = acquire_grant_table(d, xmar->id, xmar->frame,
+ xmar->nr_frames, mfn_list);
+ break;
+
default:
rc = -EOPNOTSUPP;
break;
diff --git a/xen/include/public/memory.h b/xen/include/public/memory.h
index e30a4d9794..2099b09cf5 100644
--- a/xen/include/public/memory.h
+++ b/xen/include/public/memory.h
@@ -611,6 +611,7 @@ struct xen_mem_acquire_resource {
uint16_t type;
#define XENMEM_resource_ioreq_server 0
+#define XENMEM_resource_grant_table 1
/*
* IN - a type-specific resource identifier, which must be zero
@@ -628,6 +629,10 @@ struct xen_mem_acquire_resource {
* page
* frame == 1 -> ioreq
* page
+ * type == XENMEM_resource_grant_table -> frame has same semantics
+ * as idx passed to
+ * XENMEM_add_to_physmap for
+ * XENMAPSPACE_grant_table.
*/
uint64_aligned_t frame;
/* IN/OUT - If the tools domain is PV then, upon return, gmfn_list
diff --git a/xen/include/xen/grant_table.h b/xen/include/xen/grant_table.h
index d2bd2416c4..15a83df215 100644
--- a/xen/include/xen/grant_table.h
+++ b/xen/include/xen/grant_table.h
@@ -58,5 +58,6 @@ int mem_sharing_gref_to_gfn(struct grant_table *gt,
grant_ref_t ref,
int gnttab_map_frame(struct domain *d, unsigned long idx, gfn_t gfn,
mfn_t *mfn);
+int gnttab_get_frame(struct domain *d, unsigned long idx, mfn_t *mfn);
#endif /* __XEN_GRANT_TABLE_H__ */
--
2.11.0
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