[fix] mm bugs (#7010)

* [fix] implementation fault on avl

* [fix] mm may free varea allocated statically

* [test] add test and benchmark for avl
This commit is contained in:
Shell 2023-03-03 11:51:21 +08:00 committed by GitHub
parent b7c2d1ba42
commit 0de21341f9
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6 changed files with 667 additions and 27 deletions

View File

@ -21,8 +21,11 @@
? rt_container_of(rt_container_of(pnode, struct _aspace_node, node), \
struct rt_varea, node) \
: 0
#define ASPACE_VAREA_NEXT(pva) (VAREA_ENTRY(util_avl_next(&pva->node.node)))
#define ASPACE_VAREA_FIRST(aspace) (VAREA_ENTRY(util_avl_first(&aspace->tree.tree)))
#define ASPACE_VAREA_LAST(aspace) (VAREA_ENTRY(util_avl_last(&aspace->tree.tree)))
#define ASPACE_VAREA_PREV(pva) (VAREA_ENTRY(util_avl_prev(&pva->node.node)))
typedef struct _aspace_node
{

View File

@ -65,6 +65,24 @@ static inline void _varea_post_install(rt_varea_t varea, rt_aspace_t aspace,
varea->mem_obj->on_varea_open(varea);
}
/* restore context modified by varea install */
static inline void _varea_uninstall(rt_varea_t varea)
{
rt_aspace_t aspace = varea->aspace;
if (varea->mem_obj && varea->mem_obj->on_varea_close)
varea->mem_obj->on_varea_close(varea);
rt_varea_free_pages(varea);
WR_LOCK(aspace);
_aspace_bst_remove(aspace, varea);
WR_UNLOCK(aspace);
rt_hw_mmu_unmap(aspace, varea->start, varea->size);
rt_hw_tlb_invalidate_range(aspace, varea->start, varea->size, ARCH_PAGE_SIZE);
}
int _init_lock(rt_aspace_t aspace)
{
MM_PGTBL_LOCK_INIT(aspace);
@ -144,12 +162,18 @@ static int _do_named_map(rt_aspace_t aspace, void *vaddr, rt_size_t length,
{
/* TODO try to map with huge TLB, when flag & HUGEPAGE */
rt_size_t pgsz = ARCH_PAGE_SIZE;
rt_hw_mmu_map(aspace, vaddr, phyaddr, pgsz, attr);
void *ret = rt_hw_mmu_map(aspace, vaddr, phyaddr, pgsz, attr);
if (ret == RT_NULL)
{
err = -RT_ERROR;
break;
}
vaddr += pgsz;
phyaddr += pgsz;
}
rt_hw_tlb_invalidate_range(aspace, vaddr, length, ARCH_PAGE_SIZE);
if (err == RT_EOK)
rt_hw_tlb_invalidate_range(aspace, end - length, length, ARCH_PAGE_SIZE);
return err;
}
@ -265,6 +289,7 @@ static int _mm_aspace_map(rt_aspace_t aspace, rt_varea_t varea, rt_size_t attr,
if (mem_obj->hint_free)
{
/* mem object can control mapping range and so by modifing hint */
mem_obj->hint_free(&hint);
}
@ -273,17 +298,27 @@ static int _mm_aspace_map(rt_aspace_t aspace, rt_varea_t varea, rt_size_t attr,
if (err == RT_EOK)
{
/* fill in varea data */
_varea_post_install(varea, aspace, attr, flags, mem_obj, offset);
if (MMF_TEST_CNTL(flags, MMF_PREFETCH))
{
/* do the MMU & TLB business */
err = _do_prefetch(aspace, varea, varea->start, varea->size);
if (err)
{
/* restore data structure and MMU */
_varea_uninstall(varea);
}
}
}
return err;
}
#define _IS_OVERFLOW(start, length) ((length) > (0ul - (uintptr_t)(start)))
#define _IS_OVERSIZE(start, length, limit_s, limit_sz) (((length) + (rt_size_t)((start) - (limit_start))) > (limit_size))
static inline int _not_in_range(void *start, rt_size_t length,
void *limit_start, rt_size_t limit_size)
{
@ -291,8 +326,8 @@ static inline int _not_in_range(void *start, rt_size_t length,
LOG_D("%s: [%p : %p] [%p : %p]", __func__, start, length, limit_start, limit_size);
/* assuming (base + length) will not overflow except (0) */
return start != RT_NULL
? ((length > (0ul - (uintptr_t)start)) || start < limit_start ||
(length + (rt_size_t)(start - limit_start)) > limit_size)
? (_IS_OVERFLOW(start, length) || start < limit_start ||
_IS_OVERSIZE(start, length, limit_start, limit_size))
: length > limit_size;
}
@ -334,6 +369,10 @@ int rt_aspace_map(rt_aspace_t aspace, void **addr, rt_size_t length,
if (varea)
{
err = _mm_aspace_map(aspace, varea, attr, flags, mem_obj, offset);
if (err != RT_EOK)
{
rt_free(varea);
}
}
else
{
@ -374,6 +413,7 @@ int rt_aspace_map_static(rt_aspace_t aspace, rt_varea_t varea, void **addr,
{
varea->size = length;
varea->start = *addr;
flags |= MMF_STATIC_ALLOC;
err = _mm_aspace_map(aspace, varea, attr, flags, mem_obj, offset);
}
@ -430,8 +470,7 @@ int _mm_aspace_map_phy(rt_aspace_t aspace, rt_varea_t varea,
if (err != RT_EOK)
{
_aspace_unmap(aspace, varea->start, varea->size);
rt_free(varea);
_varea_uninstall(varea);
}
}
}
@ -486,7 +525,7 @@ int rt_aspace_map_phy_static(rt_aspace_t aspace, rt_varea_t varea,
{
varea->start = hint->prefer;
varea->size = hint->map_size;
hint->flags |= MMF_MAP_FIXED;
hint->flags |= (MMF_MAP_FIXED | MMF_STATIC_ALLOC);
LOG_D("%s: start %p size %p phy at %p", __func__, varea->start, varea->size, pa_off << MM_PAGE_SHIFT);
err = _mm_aspace_map_phy(aspace, varea, hint, attr, pa_off, ret_va);
}
@ -502,21 +541,19 @@ void _aspace_unmap(rt_aspace_t aspace, void *addr, rt_size_t length)
{
struct _mm_range range = {addr, addr + length - 1};
rt_varea_t varea = _aspace_bst_search_overlap(aspace, range);
if (varea == RT_NULL)
{
LOG_I("%s: No such entry found at %p with %lx bytes\n", __func__, addr, length);
}
while (varea)
{
if (varea->mem_obj && varea->mem_obj->on_varea_close)
varea->mem_obj->on_varea_close(varea);
rt_varea_free_pages(varea);
WR_LOCK(aspace);
_aspace_bst_remove(aspace, varea);
WR_UNLOCK(aspace);
rt_hw_mmu_unmap(aspace, varea->start, varea->size);
rt_hw_tlb_invalidate_range(aspace, varea->start, varea->size, ARCH_PAGE_SIZE);
rt_free(varea);
_varea_uninstall(varea);
if (!(varea->flag & MMF_STATIC_ALLOC))
{
rt_free(varea);
}
varea = _aspace_bst_search_overlap(aspace, range);
}
}

View File

@ -51,6 +51,8 @@ enum mm_flag_cntl
MMF_TEXT = _DEF_FLAG(5),
MMF_STATIC_ALLOC = _DEF_FLAG(6),
/**
* @brief a non-locked memory can be swapped out when required, this is
* reserved for future

View File

@ -51,9 +51,11 @@ static inline void midmount_right(struct util_avl_struct *axis,
lrchild->avl_left = lchild;
lrchild->avl_right = axis;
lrchild->height = lchild->height;
lchild->height = lrheight;
axis->height = lrheight;
lrchild->parent = axis->parent;
lchild->parent = lrchild;
axis->parent = lrchild;
if (lchild->avl_right != NULL)
@ -70,7 +72,7 @@ static inline void rotate_left(struct util_avl_struct *axis,
size_t rlheight)
{
axis->avl_right = rlchild;
rchild->avl_right = axis;
rchild->avl_left = axis;
axis->height = rlheight + 1;
rchild->height = axis->height + 1;
@ -94,9 +96,11 @@ static inline void midmount_left(struct util_avl_struct *axis,
rlchild->avl_right = rchild;
rlchild->avl_left = axis;
rlchild->height = rchild->height;
rchild->height = rlheight;
axis->height = rlheight;
rlchild->parent = axis->parent;
rchild->parent = rlchild;
axis->parent = rlchild;
if (rchild->avl_left != NULL)
@ -125,7 +129,7 @@ void util_avl_rebalance(struct util_avl_struct *node,
{
struct util_avl_struct *lchild = axis->avl_left;
struct util_avl_struct *rchild = axis->avl_right;
nodeplace = node->parent ? NODE_PLACE(axis) : &root->root_node;
nodeplace = axis->parent ? NODE_PLACE(axis) : &root->root_node;
int lheight = HEIGHT_OF(lchild);
int rheight = HEIGHT_OF(rchild);
if (rheight + 1 < lheight)
@ -135,10 +139,12 @@ void util_avl_rebalance(struct util_avl_struct *node,
if (HEIGHT_OF(lchild->avl_left) >= lrheight)
{
rotate_right(axis, lchild, lrchild, nodeplace, lrheight);
axis = lchild->parent;
}
else
{
midmount_right(axis, lchild, lrchild, nodeplace, lrheight);
axis = lrchild->parent;
}
}
else if (lheight + 1 < rheight)
@ -148,20 +154,23 @@ void util_avl_rebalance(struct util_avl_struct *node,
if (HEIGHT_OF(rchild->avl_right) >= rlheight)
{
rotate_left(axis, rchild, rlchild, nodeplace, rlheight);
axis = rchild->parent;
}
else
{
midmount_left(axis, rchild, rlchild, nodeplace, rlheight);
axis = rlchild->parent;
}
}
else
{
int height = lheight < rheight ? rheight : lheight;
int height = (lheight < rheight ? rheight : lheight) + 1;
if (height == axis->height)
break;
axis->height = height;
axis = axis->parent;
}
} while (nodeplace != &root->root_node);
} while (axis);
}
void util_avl_remove(struct util_avl_struct *node, struct util_avl_root *root)
@ -196,9 +205,10 @@ void util_avl_remove(struct util_avl_struct *node, struct util_avl_root *root)
*nodeplace = rchild;
rchild->avl_left = node->avl_left;
if (rchild->avl_left != NULL)
rchild->avl_left->parent = node->parent;
rchild->avl_left->parent = rchild;
rchild->parent = node->parent;
node = rchild;
util_avl_rebalance(rchild, root);
node = rchild->parent;
}
else
{
@ -221,7 +231,8 @@ void util_avl_remove(struct util_avl_struct *node, struct util_avl_root *root)
if (sparent->avl_left != NULL)
sparent->avl_left->parent = sparent;
successor->parent = node->parent;
node = sparent;
util_avl_rebalance(sparent, root);
node = successor;
}
}

585
examples/test/avl.c Normal file
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@ -0,0 +1,585 @@
/**
* Here is the assertions to ensure rightness of bst maintenance
* After each insertion and delete, a tree must still be binary search tree,
* and still remain balanced
*/
#include <assert.h>
#include <stdlib.h>
#include <string.h>
#include <stdio.h>
#include <mm_aspace.h>
#include <mm_private.h>
#define BUF_SIZE 1000000
static void *_start;
static void *_boundary;
static int _count;
static rt_varea_t _buf[BUF_SIZE];
#define RT_ASSERT assert
static void _print_varea(rt_varea_t varea, int depth)
{
if (depth == 0)
{
printf("%p ", varea->start);
}
else
{
rt_varea_t lchild = VAREA_ENTRY(varea->node.node.avl_left);
rt_varea_t rchild = VAREA_ENTRY(varea->node.node.avl_right);
depth--;
if (lchild)
_print_varea(lchild, depth);
else
printf("0x**** ");
if (rchild)
_print_varea(rchild, depth);
else
printf("0x**** ");
}
}
static void _print_tree(rt_aspace_t aspace)
{
rt_varea_t varea = VAREA_ENTRY(aspace->tree.tree.root_node);
if (!varea)
return ;
for (size_t i = 0; i < aspace->tree.tree.root_node->height; i++) {
_print_varea(varea, i);
putchar('\n');
}
return ;
}
static int _is_bst(rt_varea_t varea)
{
rt_varea_t lchild = VAREA_ENTRY(varea->node.node.avl_left);
rt_varea_t rchild = VAREA_ENTRY(varea->node.node.avl_right);
if (lchild)
{
RT_ASSERT(lchild->node.node.parent == &varea->node.node);
RT_ASSERT(varea->start > lchild->start);
}
if (rchild)
{
RT_ASSERT(rchild->node.node.parent == &varea->node.node);
if (varea->start >= rchild->start)
{
RT_ASSERT(0);
}
}
return 1;
}
/* return height of current varea */
static int _is_balanced(rt_varea_t varea)
{
if (!varea)
{
return 1;
}
rt_varea_t lchild = VAREA_ENTRY(varea->node.node.avl_left);
rt_varea_t rchild = VAREA_ENTRY(varea->node.node.avl_right);
int lbal = _is_balanced(lchild);
int rbal = _is_balanced(rchild);
if (lbal && rbal)
{
int diff = lbal - rbal;
if (diff > 1 || diff < -1)
{
printf("lbal %d, rbal %d\n", lbal, rbal);
return 0;
}
else
{
int height = lbal > rbal ? lbal : rbal;
return height + 1;
}
}
}
/* add bst assertion */
static int _check_asc_before(rt_varea_t varea, void *arg)
{
if (varea->start >= _start && (!_boundary || varea->start >= _boundary) && _is_bst(varea))
{
_buf[_count] = varea;
_start = varea->start;
_boundary = varea->start + varea->size;
_count++;
RT_ASSERT(_count < BUF_SIZE);
}
else
{
RT_ASSERT(0);
}
return 0;
}
static int _check_asc_before_rev(rt_varea_t varea, void *arg)
{
_count--;
RT_ASSERT(varea == _buf[_count]);
return 0;
}
static int _check_asc_after(rt_varea_t varea, void *arg)
{
rt_varea_t add_elem = (rt_varea_t)arg;
if (!_is_bst(varea))
{
RT_ASSERT(0);
}
if (varea == _buf[_count])
{
_buf[_count] = 0;
_count++;
RT_ASSERT(_count < BUF_SIZE);
}
else if (add_elem && add_elem == varea)
{
/* adding, skip adding elem */
}
else if (!add_elem && varea == _buf[_count + 1])
{
/* deleting */
_buf[_count] = 0;
_buf[_count] = 0;
_count++;
RT_ASSERT(_count < BUF_SIZE);
}
else
{
printf("add_elem %p, varea %p, _count %d, in buf %p\n",
add_elem->start, varea->start, _count, _buf[_count]);
RT_ASSERT(0);
}
return 0;
}
static int _aspace_traversal(rt_aspace_t aspace, int (*fn)(rt_varea_t varea, void *arg), void *arg)
{
rt_varea_t varea = ASPACE_VAREA_FIRST(aspace);
while (varea)
{
fn(varea, arg);
varea = ASPACE_VAREA_NEXT(varea);
}
return 0;
}
static int _aspace_traversal_reverse(rt_aspace_t aspace, int (*fn)(rt_varea_t varea, void *arg), void *arg)
{
rt_varea_t varea = ASPACE_VAREA_LAST(aspace);
while (varea)
{
fn(varea, arg);
varea = ASPACE_VAREA_PREV(varea);
}
return 0;
}
static int _check_bst_before(struct rt_aspace *aspace, struct rt_varea *varea)
{
rt_varea_t root = VAREA_ENTRY(aspace->tree.tree.root_node);
int height = _is_balanced(root);
if (root)
RT_ASSERT(height);
memset(_buf, 0, sizeof(_buf)); // clear first avoiding none tree error
_start = 0;
_boundary = 0;
_count = 0;
_aspace_traversal(aspace, _check_asc_before, varea);
int saved = _count;
_aspace_traversal_reverse(aspace, _check_asc_before_rev, varea);
_count = saved;
return 1;
}
static int _check_bst_after(struct rt_aspace *aspace, struct rt_varea *varea, int isdel)
{
rt_varea_t root = VAREA_ENTRY(aspace->tree.tree.root_node);
int height = _is_balanced(root);
if (root)
RT_ASSERT(height);
int prev_count = _count;
_start = 0;
_boundary = 0;
_count = 0;
_aspace_traversal(aspace, _check_asc_after, isdel ? NULL : varea);
_count = isdel ? _count : _count + 1;
if (isdel)
{
RT_ASSERT(prev_count - 1 == _count);
}
else
{
RT_ASSERT(prev_count + 1 == _count);
}
return 1;
}
/* test library */
#define RANDOM(n) (xrand() % (n))
static unsigned int xseed = 0x11223344;
static inline unsigned int xrand(void)
{
return (((xseed = xseed * 214013L + 2531011L) >> 16) & 0x7fffffff);
}
// generate keys
static inline void init_random_keys(int *keys, int count, int seed)
{
int save_seed = time(NULL);
int *array = (int*)malloc(sizeof(int) * count);
int length = count, i;
xseed = seed;
for (i = 0; i < count; i++) {
array[i] = i;
}
for (i = 0; i < length; i++) {
int pos = xrand() % count;
int key = array[pos];
keys[i] = key;
array[pos] = array[--count];
}
free(array);
xseed = save_seed;
}
// A utility function to swap to integers
static inline void swap (int *a, int *b)
{
int temp = *a;
*a = *b;
*b = temp;
}
// A function to generate a random permutation of arr[]
static void randomize ( int arr[], int n )
{
// Use a different seed value so that we don't get same
// result each time we run this program
srand ( time(NULL) );
// Start from the last element and swap one by one. We don't
// need to run for the first element that's why i > 0
for (int i = n-1; i > 0; i--)
{
// Pick a random index from 0 to i
int j = rand() % (i+1);
// Swap arr[i] with the element at random index
swap(&arr[i], &arr[j]);
}
}
/* time */
#include <time.h>
static int gettime(void)
{
struct timespec ts;
clock_gettime(CLOCK_REALTIME_COARSE, &ts);
time_t seconds = ts.tv_sec;
int millisecond = ts.tv_nsec / 1000000;
return millisecond + seconds * 1000;
}
/* Adapt Layer */
/**
* @brief Adapter Layer for lwp AVL BST
*/
int _aspace_bst_init(struct rt_aspace *aspace)
{
aspace->tree.tree.root_node = AVL_ROOT;
return 0;
}
static int compare_overlap(void *as, void *ae, void *bs, void *be)
{
LOG_D("as %lx, ae %lx, bs %lx, be %lx", as, ae, bs, be);
int cmp;
if (as > be)
{
cmp = 1;
}
else if (ae < bs)
{
cmp = -1;
}
else
{
cmp = 0;
}
LOG_D("ret %d", cmp);
return cmp;
}
static int compare_exceed(void *as, void *ae, void *bs, void *be)
{
LOG_D("as %lx, ae %lx, bs %lx, be %lx", as, ae, bs, be);
int cmp;
if (as > bs)
{
cmp = 1;
}
else if (as < bs)
{
cmp = -1;
}
else
{
cmp = 0;
}
LOG_D("ret %d", cmp);
return cmp;
}
static struct rt_varea *search(struct util_avl_root *root,
struct _mm_range range,
int (*compare)(void *as, void *ae, void *bs,
void *be))
{
struct util_avl_struct *node = root->root_node;
while (node)
{
rt_varea_t varea = VAREA_ENTRY(node);
int cmp = compare(range.start, range.end, varea->start,
varea->start + varea->size - 1);
if (cmp < 0)
{
node = node->avl_left;
}
else if (cmp > 0)
{
node = node->avl_right;
}
else
{
return varea;
}
}
return NULL;
}
struct rt_varea *_aspace_bst_search(struct rt_aspace *aspace, void *key)
{
struct util_avl_root *root = &aspace->tree.tree;
struct _mm_range range = {key, key};
return search(root, range, compare_overlap);
}
rt_varea_t _aspace_bst_search_exceed(struct rt_aspace *aspace, void *start)
{
struct util_avl_root *root = &aspace->tree.tree;
struct util_avl_struct *node = root->root_node;
rt_varea_t closest = NULL;
ptrdiff_t min_off = PTRDIFF_MAX;
while (node)
{
rt_varea_t varea = VAREA_ENTRY(node);
void *va_s = varea->start;
int cmp = compare_exceed(start, start, va_s, va_s);
if (cmp < 0)
{
ptrdiff_t off = va_s - start;
if (off < min_off)
{
min_off = off;
closest = varea;
}
node = node->avl_left;
}
else if (cmp > 0)
{
node = node->avl_right;
}
else
{
return varea;
}
}
return closest;
}
struct rt_varea *_aspace_bst_search_overlap(struct rt_aspace *aspace,
struct _mm_range range)
{
struct util_avl_root *root = &aspace->tree.tree;
return search(root, range, compare_overlap);
}
#ifdef ENABLE_DEBUG
#include "bst_assert.h"
#else
#define _check_bst_before(x, ...)
#define _check_bst_after(x, ...)
#endif
void _aspace_bst_insert(struct rt_aspace *aspace, struct rt_varea *varea)
{
struct util_avl_root *root = &aspace->tree.tree;
struct util_avl_struct *current = NULL;
struct util_avl_struct **next = &(root->root_node);
rt_ubase_t key = (rt_ubase_t)varea->start;
/* Figure out where to put new node */
while (*next)
{
current = *next;
struct rt_varea *data = VAREA_ENTRY(current);
if (key < (rt_ubase_t)data->start)
next = &(current->avl_left);
else if (key > (rt_ubase_t)data->start)
next = &(current->avl_right);
else
return;
}
/* Add new node and rebalance tree. */
_check_bst_before(aspace, varea);
util_avl_link(&varea->node.node, current, next);
util_avl_rebalance(current, root);
_check_bst_after(aspace, varea, 0);
return;
}
void _aspace_bst_remove(struct rt_aspace *aspace, struct rt_varea *varea)
{
struct util_avl_struct *node = &varea->node.node;
_check_bst_before(aspace, varea);
util_avl_remove(node, &aspace->tree.tree);
_check_bst_after(aspace, varea, 1);
}
struct rt_aspace aspace;
/**
* @brief Simulate environment of varea and BSTs
*/
/* test data set */
int *dataset;
int loop_count;
/* preallocate varea to decrease influence by malloc routine */
struct rt_varea *_varea_buf;
#define STOPWATCH(fun, time) do { \
unsigned int _time; \
_time = gettime(); \
fun(); \
_time = gettime()-_time; \
time = _time; \
} while (0);
static void init_test(void)
{
_aspace_bst_init(&aspace);
dataset = malloc(loop_count * sizeof(*dataset));
assert(dataset);
_varea_buf = malloc(loop_count * sizeof(*_varea_buf));
assert(_varea_buf);
init_random_keys(dataset, loop_count, 0xabcdabcd);
}
static void insert_test(void)
{
for (size_t i = 0; i < loop_count; i++)
{
struct rt_varea *varea;
varea = &_varea_buf[i];
varea->start = (void *)(uintptr_t)dataset[i];
varea->size = 1;
_aspace_bst_insert(&aspace, varea);
}
}
static void search_test(void)
{
for (size_t i = 0; i < loop_count; i++)
{
void *start = (void *)(uintptr_t)dataset[i];
struct rt_varea *varea;
varea = _aspace_bst_search(&aspace, start);
assert(varea);
assert(varea->start == start);
}
}
static void delete_test(void)
{
for (size_t i = 0; i < loop_count; i++)
{
void *start = (void *)(uintptr_t)dataset[i];
struct rt_varea *varea;
varea = _aspace_bst_search(&aspace, start);
_aspace_bst_remove(&aspace, varea);
}
}
static void cleanup(void)
{
free(dataset);
free(_varea_buf);
}
int main(int argc, char *argv[])
{
if (argc == 2)
{
sscanf(argv[1], "%d", &loop_count);
}
else
{
loop_count = 1000;
}
puts("Benchmark");
printf("looping times: %d\n", loop_count);
init_test();
int endurance;
STOPWATCH(insert_test, endurance);
printf("Insertion: %d ms\n", endurance);
randomize(dataset, loop_count);
STOPWATCH(search_test, endurance);
printf("Search: %d ms\n", endurance);
randomize(dataset, loop_count);
STOPWATCH(delete_test, endurance);
printf("Delete: %d ms\n", endurance);
cleanup();
puts("Benchmark exit");
return 0;
}

View File

@ -205,6 +205,8 @@ void *rt_hw_mmu_map(rt_aspace_t aspace, void *v_addr, void *p_addr, size_t size,
if (ret != 0)
{
/* other types of return value are taken as programming error */
RT_ASSERT(ret == MMU_MAP_ERROR_NOPAGE);
/* error, undo map */
while (unmap_va != v_addr)
{