--- /dev/null
+/*
+ * libqos malloc support
+ *
+ * Copyright (c) 2014
+ *
+ * Author:
+ * John Snow <jsnow@redhat.com>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or later.
+ * See the COPYING file in the top-level directory.
+ */
+
+#include "libqos/malloc.h"
+#include "qemu-common.h"
+#include <stdio.h>
+#include <inttypes.h>
+#include <glib.h>
+
+typedef QTAILQ_HEAD(MemList, MemBlock) MemList;
+
+typedef struct MemBlock {
+ QTAILQ_ENTRY(MemBlock) MLIST_ENTNAME;
+ uint64_t size;
+ uint64_t addr;
+} MemBlock;
+
+struct QGuestAllocator {
+ QAllocOpts opts;
+ uint64_t start;
+ uint64_t end;
+ uint32_t page_size;
+
+ MemList *used;
+ MemList *free;
+};
+
+#define DEFAULT_PAGE_SIZE 4096
+
+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 MemBlock *mlist_new(uint64_t addr, uint64_t size)
+{
+ MemBlock *block;
+
+ if (!size) {
+ return NULL;
+ }
+ block = g_malloc0(sizeof(MemBlock));
+
+ block->addr = addr;
+ block->size = size;
+
+ return block;
+}
+
+static uint64_t mlist_fulfill(QGuestAllocator *s, MemBlock *freenode,
+ uint64_t size)
+{
+ uint64_t addr;
+ MemBlock *usednode;
+
+ g_assert(freenode);
+ g_assert_cmpint(freenode->size, >=, 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 ALLOC_PARANOID is set. */
+static void mlist_check(QGuestAllocator *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 mlist_alloc(QGuestAllocator *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 mlist_fulfill(s, node, size);
+}
+
+static void mlist_free(QGuestAllocator *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);
+}
+
+/*
+ * Mostly for valgrind happiness, but it does offer
+ * a chokepoint for debugging guest memory leaks, too.
+ */
+void alloc_uninit(QGuestAllocator *allocator)
+{
+ MemBlock *node;
+ MemBlock *tmp;
+ QAllocOpts mask;
+
+ /* Check for guest leaks, and destroy the list. */
+ QTAILQ_FOREACH_SAFE(node, allocator->used, MLIST_ENTNAME, tmp) {
+ if (allocator->opts & (ALLOC_LEAK_WARN | ALLOC_LEAK_ASSERT)) {
+ fprintf(stderr, "guest malloc leak @ 0x%016" PRIx64 "; "
+ "size 0x%016" PRIx64 ".\n",
+ node->addr, node->size);
+ }
+ if (allocator->opts & (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 = ALLOC_LEAK_ASSERT | ALLOC_PARANOID;
+ QTAILQ_FOREACH_SAFE(node, allocator->free, MLIST_ENTNAME, tmp) {
+ if ((allocator->opts & mask) == mask) {
+ if ((node->addr != allocator->start) ||
+ (node->size != allocator->end - allocator->start)) {
+ fprintf(stderr, "Free list is corrupted.\n");
+ g_assert_not_reached();
+ }
+ }
+
+ g_free(node);
+ }
+
+ g_free(allocator->used);
+ g_free(allocator->free);
+ g_free(allocator);
+}
+
+uint64_t guest_alloc(QGuestAllocator *allocator, size_t size)
+{
+ uint64_t rsize = size;
+ uint64_t naddr;
+
+ rsize += (allocator->page_size - 1);
+ rsize &= -allocator->page_size;
+ g_assert_cmpint((allocator->start + rsize), <=, allocator->end);
+ g_assert_cmpint(rsize, >=, size);
+
+ naddr = mlist_alloc(allocator, rsize);
+ if (allocator->opts & ALLOC_PARANOID) {
+ mlist_check(allocator);
+ }
+
+ return naddr;
+}
+
+void guest_free(QGuestAllocator *allocator, uint64_t addr)
+{
+ if (!addr) {
+ return;
+ }
+ mlist_free(allocator, addr);
+ if (allocator->opts & ALLOC_PARANOID) {
+ mlist_check(allocator);
+ }
+}
+
+QGuestAllocator *alloc_init(uint64_t start, uint64_t end)
+{
+ QGuestAllocator *s = g_malloc0(sizeof(*s));
+ MemBlock *node;
+
+ s->start = start;
+ s->end = end;
+
+ s->used = g_malloc(sizeof(MemList));
+ s->free = g_malloc(sizeof(MemList));
+ 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);
+
+ s->page_size = DEFAULT_PAGE_SIZE;
+
+ return s;
+}
+
+QGuestAllocator *alloc_init_flags(QAllocOpts opts,
+ uint64_t start, uint64_t end)
+{
+ QGuestAllocator *s = alloc_init(start, end);
+ s->opts = opts;
+ return s;
+}
+
+void alloc_set_page_size(QGuestAllocator *allocator, size_t page_size)
+{
+ /* Can't alter the page_size for an allocator in-use */
+ g_assert(QTAILQ_EMPTY(allocator->used));
+
+ g_assert(is_power_of_2(page_size));
+ allocator->page_size = page_size;
+}
+
+void alloc_set_flags(QGuestAllocator *allocator, QAllocOpts opts)
+{
+ allocator->opts |= opts;
+}
+
+void migrate_allocator(QGuestAllocator *src,
+ QGuestAllocator *dst)
+{
+ MemBlock *node, *tmp;
+ MemList *tmpused, *tmpfree;
+
+ /* The general memory layout should be equivalent,
+ * though opts can differ. */
+ g_assert_cmphex(src->start, ==, dst->start);
+ g_assert_cmphex(src->end, ==, dst->end);
+
+ /* Destroy (silently, regardless of options) the dest-list: */
+ QTAILQ_FOREACH_SAFE(node, dst->used, MLIST_ENTNAME, tmp) {
+ g_free(node);
+ }
+ QTAILQ_FOREACH_SAFE(node, dst->free, MLIST_ENTNAME, tmp) {
+ g_free(node);
+ }
+
+ tmpused = dst->used;
+ tmpfree = dst->free;
+
+ /* Inherit the lists of the source allocator: */
+ dst->used = src->used;
+ dst->free = src->free;
+
+ /* Source is now re-initialized, the source memory is 'invalid' now: */
+ src->used = tmpused;
+ src->free = tmpfree;
+ QTAILQ_INIT(src->used);
+ QTAILQ_INIT(src->free);
+ node = mlist_new(src->start, src->end - src->start);
+ QTAILQ_INSERT_HEAD(src->free, node, MLIST_ENTNAME);
+ return;
+}
Code Review / kvmfornfv.git / blobdiff