linux/tools/testing/radix-tree/regression3.c
Matthew Wilcox 3ece58a270 page cache: Convert find_get_pages_contig to XArray
There's no direct replacement for radix_tree_for_each_contig()
in the XArray API as it's an unusual thing to do.  Instead,
open-code a loop using xas_next().  This removes the only user of
radix_tree_for_each_contig() so delete the iterator from the API and
the test suite code for it.

Signed-off-by: Matthew Wilcox <willy@infradead.org>
2018-10-21 10:46:34 -04:00

95 lines
2.5 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Regression3
* Description:
* Helper radix_tree_iter_retry resets next_index to the current index.
* In following radix_tree_next_slot current chunk size becomes zero.
* This isn't checked and it tries to dereference null pointer in slot.
*
* Helper radix_tree_iter_resume reset slot to NULL and next_index to index + 1,
* for tagger iteraction it also must reset cached tags in iterator to abort
* next radix_tree_next_slot and go to slow-path into radix_tree_next_chunk.
*
* Running:
* This test should run to completion immediately. The above bug would
* cause it to segfault.
*
* Upstream commit:
* Not yet
*/
#include <linux/kernel.h>
#include <linux/gfp.h>
#include <linux/slab.h>
#include <linux/radix-tree.h>
#include <stdlib.h>
#include <stdio.h>
#include "regression.h"
void regression3_test(void)
{
RADIX_TREE(root, GFP_KERNEL);
void *ptr0 = (void *)4ul;
void *ptr = (void *)8ul;
struct radix_tree_iter iter;
void **slot;
bool first;
printv(1, "running regression test 3 (should take milliseconds)\n");
radix_tree_insert(&root, 0, ptr0);
radix_tree_tag_set(&root, 0, 0);
first = true;
radix_tree_for_each_tagged(slot, &root, &iter, 0, 0) {
printv(2, "tagged %ld %p\n", iter.index, *slot);
if (first) {
radix_tree_insert(&root, 1, ptr);
radix_tree_tag_set(&root, 1, 0);
first = false;
}
if (radix_tree_deref_retry(*slot)) {
printv(2, "retry at %ld\n", iter.index);
slot = radix_tree_iter_retry(&iter);
continue;
}
}
radix_tree_delete(&root, 1);
first = true;
radix_tree_for_each_slot(slot, &root, &iter, 0) {
printv(2, "slot %ld %p\n", iter.index, *slot);
if (first) {
radix_tree_insert(&root, 1, ptr);
first = false;
}
if (radix_tree_deref_retry(*slot)) {
printv(2, "retry at %ld\n", iter.index);
slot = radix_tree_iter_retry(&iter);
continue;
}
}
radix_tree_for_each_slot(slot, &root, &iter, 0) {
printv(2, "slot %ld %p\n", iter.index, *slot);
if (!iter.index) {
printv(2, "next at %ld\n", iter.index);
slot = radix_tree_iter_resume(slot, &iter);
}
}
radix_tree_tag_set(&root, 0, 0);
radix_tree_tag_set(&root, 1, 0);
radix_tree_for_each_tagged(slot, &root, &iter, 0, 0) {
printv(2, "tagged %ld %p\n", iter.index, *slot);
if (!iter.index) {
printv(2, "next at %ld\n", iter.index);
slot = radix_tree_iter_resume(slot, &iter);
}
}
radix_tree_delete(&root, 0);
radix_tree_delete(&root, 1);
printv(1, "regression test 3 passed\n");
}