1 files changed, 270 insertions, 10 deletions

diff --git a/tests/libqos/malloc-pc.c b/tests/libqos/malloc-pc.c
index be1d97f8bb..f4218c6451 100644
--- a/tests/libqos/malloc-pc.c
+++ b/tests/libqos/malloc-pc.c
@@ -17,45 +17,294 @@
 #include "hw/nvram/fw_cfg.h"
 
 #include "qemu-common.h"
+#include "qemu/queue.h"
 #include <glib.h>
 
 #define PAGE_SIZE (4096)
 
+#define MLIST_ENTNAME entries
+typedef QTAILQ_HEAD(MemList, MemBlock) MemList;
+typedef struct MemBlock {
+    QTAILQ_ENTRY(MemBlock) MLIST_ENTNAME;
+    uint64_t size;
+    uint64_t addr;
+} MemBlock;
+
 typedef struct PCAlloc
 {
     QGuestAllocator alloc;
-
+    PCAllocOpts opts;
     uint64_t start;
     uint64_t end;
+
+    MemList used;
+    MemList free;
 } PCAlloc;
 
-static uint64_t pc_alloc(QGuestAllocator *allocator, size_t size)
+static MemBlock *mlist_new(uint64_t addr, uint64_t size)
 {
-    PCAlloc *s = container_of(allocator, PCAlloc, alloc);
-    uint64_t addr;
+    MemBlock *block;
+
+    if (!size) {
+        return NULL;
+    }
+    block = g_malloc0(sizeof(MemBlock));
 
+    block->addr = addr;
+    block->size = size;
 
-    size += (PAGE_SIZE - 1);
-    size &= -PAGE_SIZE;
+    return block;
+}
+
+static void mlist_delete(MemList *list, MemBlock *node)
+{
+    g_assert(list && node);
+    QTAILQ_REMOVE(list, node, MLIST_ENTNAME);
+    g_free(node);
+}
+
+static MemBlock *mlist_find_key(MemList *head, uint64_t addr)
+{
+    MemBlock *node;
+    QTAILQ_FOREACH(node, head, MLIST_ENTNAME) {
+        if (node->addr == addr) {
+            return node;
+        }
+    }
+    return NULL;
+}
+
+static MemBlock *mlist_find_space(MemList *head, uint64_t size)
+{
+    MemBlock *node;
+
+    QTAILQ_FOREACH(node, head, MLIST_ENTNAME) {
+        if (node->size >= size) {
+            return node;
+        }
+    }
+    return NULL;
+}
+
+static MemBlock *mlist_sort_insert(MemList *head, MemBlock *insr)
+{
+    MemBlock *node;
+    g_assert(head && insr);
+
+    QTAILQ_FOREACH(node, head, MLIST_ENTNAME) {
+        if (insr->addr < node->addr) {
+            QTAILQ_INSERT_BEFORE(node, insr, MLIST_ENTNAME);
+            return insr;
+        }
+    }
+
+    QTAILQ_INSERT_TAIL(head, insr, MLIST_ENTNAME);
+    return insr;
+}
+
+static inline uint64_t mlist_boundary(MemBlock *node)
+{
+    return node->size + node->addr;
+}
+
+static MemBlock *mlist_join(MemList *head, MemBlock *left, MemBlock *right)
+{
+    g_assert(head && left && right);
+
+    left->size += right->size;
+    mlist_delete(head, right);
+    return left;
+}
+
+static void mlist_coalesce(MemList *head, MemBlock *node)
+{
+    g_assert(node);
+    MemBlock *left;
+    MemBlock *right;
+    char merge;
+
+    do {
+        merge = 0;
+        left = QTAILQ_PREV(node, MemList, MLIST_ENTNAME);
+        right = QTAILQ_NEXT(node, MLIST_ENTNAME);
+
+        /* clowns to the left of me */
+        if (left && mlist_boundary(left) == node->addr) {
+            node = mlist_join(head, left, node);
+            merge = 1;
+        }
+
+        /* jokers to the right */
+        if (right && mlist_boundary(node) == right->addr) {
+            node = mlist_join(head, node, right);
+            merge = 1;
+        }
+
+    } while (merge);
+}
+
+static uint64_t pc_mlist_fulfill(PCAlloc *s, MemBlock *freenode, uint64_t size)
+{
+    uint64_t addr;
+    MemBlock *usednode;
 
-    g_assert_cmpint((s->start + size), <=, s->end);
+    g_assert(freenode);
+    g_assert_cmpint(freenode->size, >=, size);
 
-    addr = s->start;
-    s->start += size;
+    addr = freenode->addr;
+    if (freenode->size == size) {
+        /* re-use this freenode as our used node */
+        QTAILQ_REMOVE(&s->free, freenode, MLIST_ENTNAME);
+        usednode = freenode;
+    } else {
+        /* adjust the free node and create a new used node */
+        freenode->addr += size;
+        freenode->size -= size;
+        usednode = mlist_new(addr, size);
+    }
 
+    mlist_sort_insert(&s->used, usednode);
     return addr;
 }
 
+/* To assert the correctness of the list.
+ * Used only if PC_ALLOC_PARANOID is set. */
+static void pc_mlist_check(PCAlloc *s)
+{
+    MemBlock *node;
+    uint64_t addr = s->start > 0 ? s->start - 1 : 0;
+    uint64_t next = s->start;
+
+    QTAILQ_FOREACH(node, &s->free, MLIST_ENTNAME) {
+        g_assert_cmpint(node->addr, >, addr);
+        g_assert_cmpint(node->addr, >=, next);
+        addr = node->addr;
+        next = node->addr + node->size;
+    }
+
+    addr = s->start > 0 ? s->start - 1 : 0;
+    next = s->start;
+    QTAILQ_FOREACH(node, &s->used, MLIST_ENTNAME) {
+        g_assert_cmpint(node->addr, >, addr);
+        g_assert_cmpint(node->addr, >=, next);
+        addr = node->addr;
+        next = node->addr + node->size;
+    }
+}
+
+static uint64_t pc_mlist_alloc(PCAlloc *s, uint64_t size)
+{
+    MemBlock *node;
+
+    node = mlist_find_space(&s->free, size);
+    if (!node) {
+        fprintf(stderr, "Out of guest memory.\n");
+        g_assert_not_reached();
+    }
+    return pc_mlist_fulfill(s, node, size);
+}
+
+static void pc_mlist_free(PCAlloc *s, uint64_t addr)
+{
+    MemBlock *node;
+
+    if (addr == 0) {
+        return;
+    }
+
+    node = mlist_find_key(&s->used, addr);
+    if (!node) {
+        fprintf(stderr, "Error: no record found for an allocation at "
+                "0x%016" PRIx64 ".\n",
+                addr);
+        g_assert_not_reached();
+    }
+
+    /* Rip it out of the used list and re-insert back into the free list. */
+    QTAILQ_REMOVE(&s->used, node, MLIST_ENTNAME);
+    mlist_sort_insert(&s->free, node);
+    mlist_coalesce(&s->free, node);
+}
+
+static uint64_t pc_alloc(QGuestAllocator *allocator, size_t size)
+{
+    PCAlloc *s = container_of(allocator, PCAlloc, alloc);
+    uint64_t rsize = size;
+    uint64_t naddr;
+
+    rsize += (PAGE_SIZE - 1);
+    rsize &= -PAGE_SIZE;
+    g_assert_cmpint((s->start + rsize), <=, s->end);
+    g_assert_cmpint(rsize, >=, size);
+
+    naddr = pc_mlist_alloc(s, rsize);
+    if (s->opts & PC_ALLOC_PARANOID) {
+        pc_mlist_check(s);
+    }
+
+    return naddr;
+}
+
 static void pc_free(QGuestAllocator *allocator, uint64_t addr)
 {
+    PCAlloc *s = container_of(allocator, PCAlloc, alloc);
+
+    pc_mlist_free(s, addr);
+    if (s->opts & PC_ALLOC_PARANOID) {
+        pc_mlist_check(s);
+    }
+}
+
+/*
+ * Mostly for valgrind happiness, but it does offer
+ * a chokepoint for debugging guest memory leaks, too.
+ */
+void pc_alloc_uninit(QGuestAllocator *allocator)
+{
+    PCAlloc *s = container_of(allocator, PCAlloc, alloc);
+    MemBlock *node;
+    MemBlock *tmp;
+    PCAllocOpts mask;
+
+    /* Check for guest leaks, and destroy the list. */
+    QTAILQ_FOREACH_SAFE(node, &s->used, MLIST_ENTNAME, tmp) {
+        if (s->opts & (PC_ALLOC_LEAK_WARN | PC_ALLOC_LEAK_ASSERT)) {
+            fprintf(stderr, "guest malloc leak @ 0x%016" PRIx64 "; "
+                    "size 0x%016" PRIx64 ".\n",
+                    node->addr, node->size);
+        }
+        if (s->opts & (PC_ALLOC_LEAK_ASSERT)) {
+            g_assert_not_reached();
+        }
+        g_free(node);
+    }
+
+    /* If we have previously asserted that there are no leaks, then there
+     * should be only one node here with a specific address and size. */
+    mask = PC_ALLOC_LEAK_ASSERT | PC_ALLOC_PARANOID;
+    QTAILQ_FOREACH_SAFE(node, &s->free, MLIST_ENTNAME, tmp) {
+        if ((s->opts & mask) == mask) {
+            if ((node->addr != s->start) ||
+                (node->size != s->end - s->start)) {
+                fprintf(stderr, "Free list is corrupted.\n");
+                g_assert_not_reached();
+            }
+        }
+
+        g_free(node);
+    }
+
+    g_free(s);
 }
 
-QGuestAllocator *pc_alloc_init(void)
+QGuestAllocator *pc_alloc_init_flags(PCAllocOpts flags)
 {
     PCAlloc *s = g_malloc0(sizeof(*s));
     uint64_t ram_size;
     QFWCFG *fw_cfg = pc_fw_cfg_init();
+    MemBlock *node;
 
+    s->opts = flags;
     s->alloc.alloc = pc_alloc;
     s->alloc.free = pc_free;
 
@@ -70,5 +319,16 @@ QGuestAllocator *pc_alloc_init(void)
     /* clean-up */
     g_free(fw_cfg);
 
+    QTAILQ_INIT(&s->used);
+    QTAILQ_INIT(&s->free);
+
+    node = mlist_new(s->start, s->end - s->start);
+    QTAILQ_INSERT_HEAD(&s->free, node, MLIST_ENTNAME);
+
     return &s->alloc;
 }
+
+inline QGuestAllocator *pc_alloc_init(void)
+{
+    return pc_alloc_init_flags(PC_ALLOC_NO_FLAGS);
+}