[PATCH v5 6/8] libxl: build e820 map for vnodes

[Elena Ufimtseva <ufimtseva@gmail.com>]

build e820 map from vnuma memory ranges.

Signed-off-by: Elena Ufimtseva <ufimtseva@gmail.com>
---
 tools/libxl/libxl_internal.h |   10 ++++
 tools/libxl/libxl_numa.c     |  125 ++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 135 insertions(+)

diff --git a/tools/libxl/libxl_internal.h b/tools/libxl/libxl_internal.h
index 082749e..7ae8508 100644
--- a/tools/libxl/libxl_internal.h
+++ b/tools/libxl/libxl_internal.h
@@ -3113,6 +3113,16 @@ void libxl__numa_candidate_put_nodemap(libxl__gc *gc,
  */
 #define CTYPE(isfoo,c) (isfoo((unsigned char)(c)))
 
+int e820_sanitize(libxl_ctx *ctx, struct e820entry src[],
+                         uint32_t *nr_entries,
+                         unsigned long map_limitkb,
+                         unsigned long balloon_kb);
+
+int libxl__vnuma_align_mem(libxl__gc *gc,
+                            uint32_t domid,
+                            struct libxl_domain_build_info *b_info,
+                            vmemrange_t *memblks);
+
 
 #endif
 
diff --git a/tools/libxl/libxl_numa.c b/tools/libxl/libxl_numa.c
index 94ca4fe..38f1546 100644
--- a/tools/libxl/libxl_numa.c
+++ b/tools/libxl/libxl_numa.c
@@ -19,6 +19,8 @@
 
 #include "libxl_internal.h"
 
+#include "libxl_vnuma.h"
+
 /*
  * What follows are helpers for generating all the k-combinations
  * without repetitions of a set S with n elements in it. Formally
@@ -508,6 +510,129 @@ int libxl__get_numa_candidate(libxl__gc *gc,
 }
 
 /*
+/*
+ * Used for PV guest with e802_host enabled and thus
+ * having non-contiguous e820 memory map.
+ */
+static unsigned long e820_memory_hole_size(unsigned long start,
+                                            unsigned long end,
+                                            struct e820entry e820[],
+                                            unsigned int nr)
+{
+    unsigned int i;
+    unsigned long absent, start_pfn, end_pfn;
+
+    absent = end - start;
+    for (i = 0; i < nr; i++) {
+        /* if not E820_RAM region, skip it and dont substract from absent */
+        if (e820[i].type == E820_RAM) {
+            start_pfn = e820[i].addr;
+            end_pfn =   e820[i].addr + e820[i].size;
+            /* beginning pfn is in this region? */
+            if (start >= start_pfn && start <= end_pfn) {
+                if (end > end_pfn)
+                    absent -= end_pfn - start;
+                else
+                    /* fit the region? then no absent pages */
+                    absent -= end - start;
+                continue;
+            }
+            /* found the end of range in this region? */
+            if (end <= end_pfn && end >= start_pfn) {
+                absent -= end - start_pfn;
+                /* no need to look for more ranges */
+                break;
+            }
+        }
+    }
+    return absent;
+}
+
+/*
+ * Checks for the beginnig and end of RAM in e820 map for domain
+ * and aligns start of first and end of last vNUMA memory block to
+ * that map. vnode memory size are passed here Megabytes.
+ * For PV guest e820 map has fixed hole sizes.
+ */
+int libxl__vnuma_align_mem(libxl__gc *gc,
+                            uint32_t domid,
+                            libxl_domain_build_info *b_info, /* IN: mem sizes */
+                            vmemrange_t *memblks)        /* OUT: linux numa blocks in pfn */
+{
+    unsigned int i, j;
+    int rc;
+    uint64_t next_start_pfn, end_max = 0, size;//, mem_hole;
+    uint32_t nr;
+    struct e820entry map[E820MAX];
+
+    if (b_info->nr_nodes == 0)
+        return -EINVAL;
+    libxl_ctx *ctx = libxl__gc_owner(gc);
+
+    /* retreive e820 map for this host */
+    rc = xc_get_machine_memory_map(ctx->xch, map, E820MAX);
+
+    if (rc < 0) {
+        errno = rc;
+        return -EINVAL;
+    }
+    nr = rc;
+    rc = e820_sanitize(ctx, map, &nr, b_info->target_memkb,
+                       (b_info->max_memkb - b_info->target_memkb) +
+                       b_info->u.pv.slack_memkb);
+    if (rc)
+    {
+        errno = rc;
+        return -EINVAL;
+    }
+
+    /* max pfn for this host */
+    for (j = nr - 1; j >= 0; j--)
+        if (map[j].type == E820_RAM) {
+            end_max = map[j].addr + map[j].size;
+            break;
+        }
+
+    memset(memblks, 0, sizeof(*memblks) * b_info->nr_nodes);
+    next_start_pfn = 0;
+
+    memblks[0].start = map[0].addr;
+
+    for (i = 0; i < b_info->nr_nodes; i++) {
+        /* start can be not zero */
+        memblks[i].start += next_start_pfn;
+        memblks[i].end = memblks[i].start + (b_info->numa_memszs[i] << 20);
+
+        size = memblks[i].end - memblks[i].start;
+        /*
+         * For pv host with e820_host option turned on we need
+         * to take into account memory holes. For pv host with
+         * e820_host disabled or unset, the map is contiguous
+         * RAM region.
+         */
+        if (libxl_defbool_val(b_info->u.pv.e820_host)) {
+            while((memblks[i].end - memblks[i].start -
+                   e820_memory_hole_size(memblks[i].start,
+                   memblks[i].end, map, nr)) < size )
+            {
+                memblks[i].end += MIN_VNODE_SIZE << 10;
+                if (memblks[i].end > end_max) {
+                    memblks[i].end = end_max;
+                    break;
+                }
+            }
+        }
+        next_start_pfn = memblks[i].end;
+        LIBXL__LOG(ctx, LIBXL__LOG_DEBUG,"i %d, start  = %#010lx, end = %#010lx\n",
+                    i, memblks[i].start, memblks[i].end);
+    }
+    if (memblks[i-1].end > end_max)
+        memblks[i-1].end = end_max;
+
+    return 0;
+}
+
+/*
  * Local variables:
  * mode: C
  * c-basic-offset: 4
-- 
1.7.10.4