[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

[PATCH v3] tools: unify page type checking in save/restore



Users of xc_get_pfn_type_batch may want to sanity check the data
returned by Xen. Add helpers for this purpose:

is_known_page_type verifies the type returned by Xen on the saving
side, or the incoming type for a page on the restoring side, is known
by the save/restore code.

page_type_to_populate decides if a page with the given known type
needs to be populated on the restoring side.

page_type_has_stream_data decides if a page with the given known type
needs to be send, or if the stream on the restoring side contains a
data page.

While touching the code, simplify the logic check in populate_pfns.

No change in behavior intended.

Signed-off-by: Olaf Hering <olaf@xxxxxxxxx>

v03:
- fold all three helpers into a single patch
v02:
- rename xc_is_known_page_type to sr_is_known_page_type
- move from ctrl/xc_private.h to saverestore/common.h (jgross)
---
 tools/libs/saverestore/common.h  | 86 ++++++++++++++++++++++++++++++++
 tools/libs/saverestore/restore.c | 38 +++-----------
 tools/libs/saverestore/save.c    | 18 +++----
 3 files changed, 99 insertions(+), 43 deletions(-)

compile-tested only

diff --git a/tools/libs/saverestore/common.h b/tools/libs/saverestore/common.h
index ca2eb47a4f..283d3c7213 100644
--- a/tools/libs/saverestore/common.h
+++ b/tools/libs/saverestore/common.h
@@ -467,6 +467,92 @@ int populate_pfns(struct xc_sr_context *ctx, unsigned int 
count,
 /* Handle a STATIC_DATA_END record. */
 int handle_static_data_end(struct xc_sr_context *ctx);
 
+/* Sanitiy check for types returned by Xen */
+static inline bool is_known_page_type(uint32_t type)
+{
+    switch ( type )
+    {
+    case XEN_DOMCTL_PFINFO_NOTAB:
+
+    case XEN_DOMCTL_PFINFO_L1TAB:
+    case XEN_DOMCTL_PFINFO_L1TAB | XEN_DOMCTL_PFINFO_LPINTAB:
+
+    case XEN_DOMCTL_PFINFO_L2TAB:
+    case XEN_DOMCTL_PFINFO_L2TAB | XEN_DOMCTL_PFINFO_LPINTAB:
+
+    case XEN_DOMCTL_PFINFO_L3TAB:
+    case XEN_DOMCTL_PFINFO_L3TAB | XEN_DOMCTL_PFINFO_LPINTAB:
+
+    case XEN_DOMCTL_PFINFO_L4TAB:
+    case XEN_DOMCTL_PFINFO_L4TAB | XEN_DOMCTL_PFINFO_LPINTAB:
+
+    case XEN_DOMCTL_PFINFO_XTAB:
+    case XEN_DOMCTL_PFINFO_XALLOC: /* Synthetic type in Xen 4.2 - 4.5 */
+    case XEN_DOMCTL_PFINFO_BROKEN:
+        return true;
+    default:
+        break;
+    }
+    return false;
+}
+
+static inline bool page_type_to_populate(uint32_t type)
+{
+    switch ( type )
+    {
+    case XEN_DOMCTL_PFINFO_NOTAB:
+
+    case XEN_DOMCTL_PFINFO_L1TAB:
+    case XEN_DOMCTL_PFINFO_L1TAB | XEN_DOMCTL_PFINFO_LPINTAB:
+
+    case XEN_DOMCTL_PFINFO_L2TAB:
+    case XEN_DOMCTL_PFINFO_L2TAB | XEN_DOMCTL_PFINFO_LPINTAB:
+
+    case XEN_DOMCTL_PFINFO_L3TAB:
+    case XEN_DOMCTL_PFINFO_L3TAB | XEN_DOMCTL_PFINFO_LPINTAB:
+
+    case XEN_DOMCTL_PFINFO_L4TAB:
+    case XEN_DOMCTL_PFINFO_L4TAB | XEN_DOMCTL_PFINFO_LPINTAB:
+
+    case XEN_DOMCTL_PFINFO_XALLOC:
+        return true;
+
+    case XEN_DOMCTL_PFINFO_XTAB:
+    case XEN_DOMCTL_PFINFO_BROKEN:
+    default:
+        break;
+    }
+    return false;
+}
+
+static inline bool page_type_has_stream_data(uint32_t type)
+{
+    switch ( type )
+    {
+    case XEN_DOMCTL_PFINFO_NOTAB:
+
+    case XEN_DOMCTL_PFINFO_L1TAB:
+    case XEN_DOMCTL_PFINFO_L1TAB | XEN_DOMCTL_PFINFO_LPINTAB:
+
+    case XEN_DOMCTL_PFINFO_L2TAB:
+    case XEN_DOMCTL_PFINFO_L2TAB | XEN_DOMCTL_PFINFO_LPINTAB:
+
+    case XEN_DOMCTL_PFINFO_L3TAB:
+    case XEN_DOMCTL_PFINFO_L3TAB | XEN_DOMCTL_PFINFO_LPINTAB:
+
+    case XEN_DOMCTL_PFINFO_L4TAB:
+    case XEN_DOMCTL_PFINFO_L4TAB | XEN_DOMCTL_PFINFO_LPINTAB:
+        return true;
+
+    case XEN_DOMCTL_PFINFO_XTAB:
+    case XEN_DOMCTL_PFINFO_BROKEN:
+    case XEN_DOMCTL_PFINFO_XALLOC:
+    default:
+        break;
+    }
+
+    return false;
+}
 #endif
 /*
  * Local variables:
diff --git a/tools/libs/saverestore/restore.c b/tools/libs/saverestore/restore.c
index be259a1c6b..23ed359e4e 100644
--- a/tools/libs/saverestore/restore.c
+++ b/tools/libs/saverestore/restore.c
@@ -152,9 +152,7 @@ int populate_pfns(struct xc_sr_context *ctx, unsigned int 
count,
 
     for ( i = 0; i < count; ++i )
     {
-        if ( (!types || (types &&
-                         (types[i] != XEN_DOMCTL_PFINFO_XTAB &&
-                          types[i] != XEN_DOMCTL_PFINFO_BROKEN))) &&
+        if ( (!types || page_type_to_populate(types[i])) &&
              !pfn_is_populated(ctx, original_pfns[i]) )
         {
             rc = pfn_set_populated(ctx, original_pfns[i]);
@@ -233,25 +231,8 @@ static int process_page_data(struct xc_sr_context *ctx, 
unsigned int count,
     {
         ctx->restore.ops.set_page_type(ctx, pfns[i], types[i]);
 
-        switch ( types[i] )
-        {
-        case XEN_DOMCTL_PFINFO_NOTAB:
-
-        case XEN_DOMCTL_PFINFO_L1TAB:
-        case XEN_DOMCTL_PFINFO_L1TAB | XEN_DOMCTL_PFINFO_LPINTAB:
-
-        case XEN_DOMCTL_PFINFO_L2TAB:
-        case XEN_DOMCTL_PFINFO_L2TAB | XEN_DOMCTL_PFINFO_LPINTAB:
-
-        case XEN_DOMCTL_PFINFO_L3TAB:
-        case XEN_DOMCTL_PFINFO_L3TAB | XEN_DOMCTL_PFINFO_LPINTAB:
-
-        case XEN_DOMCTL_PFINFO_L4TAB:
-        case XEN_DOMCTL_PFINFO_L4TAB | XEN_DOMCTL_PFINFO_LPINTAB:
-
+        if ( page_type_has_stream_data(types[i]) )
             mfns[nr_pages++] = ctx->restore.ops.pfn_to_gfn(ctx, pfns[i]);
-            break;
-        }
     }
 
     /* Nothing to do? */
@@ -271,14 +252,8 @@ static int process_page_data(struct xc_sr_context *ctx, 
unsigned int count,
 
     for ( i = 0, j = 0; i < count; ++i )
     {
-        switch ( types[i] )
-        {
-        case XEN_DOMCTL_PFINFO_XTAB:
-        case XEN_DOMCTL_PFINFO_BROKEN:
-        case XEN_DOMCTL_PFINFO_XALLOC:
-            /* No page data to deal with. */
+        if ( !page_type_has_stream_data(types[i]) )
             continue;
-        }
 
         if ( map_errs[j] )
         {
@@ -406,15 +381,14 @@ static int handle_page_data(struct xc_sr_context *ctx, 
struct xc_sr_record *rec)
         }
 
         type = (pages->pfn[i] & PAGE_DATA_TYPE_MASK) >> 32;
-        if ( ((type >> XEN_DOMCTL_PFINFO_LTAB_SHIFT) >= 5) &&
-             ((type >> XEN_DOMCTL_PFINFO_LTAB_SHIFT) <= 8) )
+        if ( !is_known_page_type(type) )
         {
-            ERROR("Invalid type %#"PRIx32" for pfn %#"PRIpfn" (index %u)",
+            ERROR("Unknown type %#"PRIx32" for pfn %#"PRIpfn" (index %u)",
                   type, pfn, i);
             goto err;
         }
 
-        if ( type < XEN_DOMCTL_PFINFO_BROKEN )
+        if ( page_type_has_stream_data(type) )
             /* NOTAB and all L1 through L4 tables (including pinned) should
              * have a page worth of data in the record. */
             pages_of_data++;
diff --git a/tools/libs/saverestore/save.c b/tools/libs/saverestore/save.c
index 9540c93cde..fe3a7b3994 100644
--- a/tools/libs/saverestore/save.c
+++ b/tools/libs/saverestore/save.c
@@ -147,14 +147,15 @@ static int write_batch(struct xc_sr_context *ctx)
 
     for ( i = 0; i < nr_pfns; ++i )
     {
-        switch ( types[i] )
+        if ( !is_known_page_type(types[i]) )
         {
-        case XEN_DOMCTL_PFINFO_BROKEN:
-        case XEN_DOMCTL_PFINFO_XALLOC:
-        case XEN_DOMCTL_PFINFO_XTAB:
-            continue;
+            ERROR("Unknown type %#"PRIpfn" for pfn %#"PRIpfn, types[i], 
mfns[i]);
+            goto err;
         }
 
+        if ( !page_type_has_stream_data(types[i]) )
+            continue;
+
         mfns[nr_pages++] = mfns[i];
     }
 
@@ -171,13 +172,8 @@ static int write_batch(struct xc_sr_context *ctx)
 
         for ( i = 0, p = 0; i < nr_pfns; ++i )
         {
-            switch ( types[i] )
-            {
-            case XEN_DOMCTL_PFINFO_BROKEN:
-            case XEN_DOMCTL_PFINFO_XALLOC:
-            case XEN_DOMCTL_PFINFO_XTAB:
+            if ( !page_type_has_stream_data(types[i]) )
                 continue;
-            }
 
             if ( errors[p] )
             {



 


Rackspace

Lists.xenproject.org is hosted with RackSpace, monitoring our
servers 24x7x365 and backed by RackSpace's Fanatical Support®.