libxl: provide libxl_bitmap_{or,and}

New functions to provide logical and and or of two bitmaps.  These are
generically useful utility functions added to the public API for the
benefit of libxl's users.

In the future they may also be useful internally, e.g. in the
vNUMA configuration check function.

Signed-off-by: Linda Jacobson <lindaj@jma3.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
[ ijc -- rewrote commit message and fixed typo ]

diff --git a/tools/libxl/libxl.h b/tools/libxl/libxl.h
index 1cf5699e94488208ad4eaf0bedfc829d4f124f4b..44bd8e20b42d48c4377f2d599fc552cd394c5fa2 100644 (file)
--- a/tools/libxl/libxl.h
+++ b/tools/libxl/libxl.h
@@ -99,6 +99,15 @@
  */
 #define LIBXL_HAVE_CPUPOOL_ADD_REM_CPUMAP 1
 
+/*
+ *
+ * LIBXL_HAVE_BITMAP_AND_OR
+ *
+ * If this is defined, libxl has two library functions, libxl_bitmap_and
+ * and libxl_bitmap_or to compute the logical and and or of two bitmaps
+ */
+#define LIBXL_HAVE_BITMAP_AND_OR 1
+
 /*
  * LIBXL_HAVE_FIRMWARE_PASSTHROUGH indicates the feature for
  * passing in SMBIOS and ACPI firmware to HVM guests is present

diff --git a/tools/libxl/libxl_utils.c b/tools/libxl/libxl_utils.c
index 9053b2798a443fb8b65b8dbec9aa1703580a3230..67c0b1c5622e48862b9838602f09646c1e24efb2 100644 (file)
--- a/tools/libxl/libxl_utils.c
+++ b/tools/libxl/libxl_utils.c
@@ -691,6 +691,76 @@ void libxl_bitmap_reset(libxl_bitmap *bitmap, int bit)
     bitmap->map[bit / 8] &= ~(1 << (bit & 7));
 }
 
+int libxl_bitmap_or(libxl_ctx *ctx, libxl_bitmap *or_map,
+                    const libxl_bitmap *map1, const libxl_bitmap *map2)
+{
+    GC_INIT(ctx);
+    int rc;
+    uint32_t i;
+    const libxl_bitmap *large_map;
+    const libxl_bitmap *small_map;
+
+    if (map1->size > map2->size) {
+        large_map = map1;
+        small_map = map2;
+    } else {
+        large_map = map2;
+        small_map = map1;
+    }
+
+    rc = libxl_bitmap_alloc(ctx, or_map, large_map->size * 8);
+    if (rc)
+        goto out;
+
+    /*
+     *  If bitmaps aren't the same size, their union (logical or) will
+     *  be size of larger bit map.  Any bit past the end of the
+     *  smaller bit map, will match the larger one.
+     */
+    for (i = 0; i < small_map->size; i++)
+        or_map->map[i] = (small_map->map[i] | large_map->map[i]);
+
+    for (i = small_map->size; i < large_map->size; i++)
+        or_map->map[i] = large_map->map[i];
+
+out:
+    GC_FREE;
+    return rc;
+}
+
+int libxl_bitmap_and(libxl_ctx *ctx, libxl_bitmap *and_map,
+                     const libxl_bitmap *map1, const libxl_bitmap *map2)
+{
+    GC_INIT(ctx);
+    int rc;
+    uint32_t i;
+    const libxl_bitmap *large_map;
+    const libxl_bitmap *small_map;
+
+    if (map1->size > map2->size) {
+        large_map = map1;
+        small_map = map2;
+    } else {
+        large_map = map2;
+        small_map = map1;
+    }
+
+    rc = libxl_bitmap_alloc(ctx, and_map, small_map->size * 8);
+    if (rc)
+        goto out;
+
+    /*
+     *  If bitmaps aren't same size, their 'and' will be size of
+     *  smaller bit map
+     */
+    for (i = 0; i < and_map->size; i++)
+        and_map->map[i] = (large_map->map[i] & small_map->map[i]);
+
+out:
+    GC_FREE;
+    return rc;
+}
+
 int libxl_bitmap_count_set(const libxl_bitmap *bitmap)
 {
     int i, nr_set_bits = 0;

diff --git a/tools/libxl/libxl_utils.h b/tools/libxl/libxl_utils.h
index 68b5580ff2bb66ee4ec25a8087af2f51204d1990..1c1761da4e1ede1c31fbdd5d4bf48b0b587c10e3 100644 (file)
--- a/tools/libxl/libxl_utils.h
+++ b/tools/libxl/libxl_utils.h
@@ -90,6 +90,12 @@ int libxl_bitmap_test(const libxl_bitmap *bitmap, int bit);
 void libxl_bitmap_set(libxl_bitmap *bitmap, int bit);
 void libxl_bitmap_reset(libxl_bitmap *bitmap, int bit);
 int libxl_bitmap_count_set(const libxl_bitmap *bitmap);
+int libxl_bitmap_or(libxl_ctx *ctx, libxl_bitmap *or_map,
+                    const libxl_bitmap *map1,
+                    const libxl_bitmap *map2);
+int libxl_bitmap_and(libxl_ctx *ctx, libxl_bitmap *and_map,
+                     const libxl_bitmap *map1,
+                     const libxl_bitmap *map2);
 char *libxl_bitmap_to_hex_string(libxl_ctx *ctx, const libxl_bitmap *bitmap);
 static inline void libxl_bitmap_set_any(libxl_bitmap *bitmap)
 {