linux/fs/btrfs/tests/extent-io-tests.c
Filipe Manana 202f64ef42 Btrfs: make test_find_first_clear_extent_bit fail on incorrect results
If any call to find_first_clear_extent_bit() returns an unexpected result,
the test should fail and not just print an error message, otherwise it
makes detection of regressions much harder to notice.

Fixes: 1eaebb341d ("btrfs: Don't trim returned range based on input value in find_first_clear_extent_bit")
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-09-09 14:59:05 +02:00

555 lines
14 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (C) 2013 Fusion IO. All rights reserved.
*/
#include <linux/pagemap.h>
#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/sizes.h>
#include "btrfs-tests.h"
#include "../ctree.h"
#include "../extent_io.h"
#include "../btrfs_inode.h"
#define PROCESS_UNLOCK (1 << 0)
#define PROCESS_RELEASE (1 << 1)
#define PROCESS_TEST_LOCKED (1 << 2)
static noinline int process_page_range(struct inode *inode, u64 start, u64 end,
unsigned long flags)
{
int ret;
struct page *pages[16];
unsigned long index = start >> PAGE_SHIFT;
unsigned long end_index = end >> PAGE_SHIFT;
unsigned long nr_pages = end_index - index + 1;
int i;
int count = 0;
int loops = 0;
while (nr_pages > 0) {
ret = find_get_pages_contig(inode->i_mapping, index,
min_t(unsigned long, nr_pages,
ARRAY_SIZE(pages)), pages);
for (i = 0; i < ret; i++) {
if (flags & PROCESS_TEST_LOCKED &&
!PageLocked(pages[i]))
count++;
if (flags & PROCESS_UNLOCK && PageLocked(pages[i]))
unlock_page(pages[i]);
put_page(pages[i]);
if (flags & PROCESS_RELEASE)
put_page(pages[i]);
}
nr_pages -= ret;
index += ret;
cond_resched();
loops++;
if (loops > 100000) {
printk(KERN_ERR
"stuck in a loop, start %llu, end %llu, nr_pages %lu, ret %d\n",
start, end, nr_pages, ret);
break;
}
}
return count;
}
static int test_find_delalloc(u32 sectorsize)
{
struct inode *inode;
struct extent_io_tree *tmp;
struct page *page;
struct page *locked_page = NULL;
unsigned long index = 0;
/* In this test we need at least 2 file extents at its maximum size */
u64 max_bytes = BTRFS_MAX_EXTENT_SIZE;
u64 total_dirty = 2 * max_bytes;
u64 start, end, test_start;
bool found;
int ret = -EINVAL;
test_msg("running find delalloc tests");
inode = btrfs_new_test_inode();
if (!inode) {
test_std_err(TEST_ALLOC_INODE);
return -ENOMEM;
}
tmp = &BTRFS_I(inode)->io_tree;
/*
* Passing NULL as we don't have fs_info but tracepoints are not used
* at this point
*/
extent_io_tree_init(NULL, tmp, IO_TREE_SELFTEST, NULL);
/*
* First go through and create and mark all of our pages dirty, we pin
* everything to make sure our pages don't get evicted and screw up our
* test.
*/
for (index = 0; index < (total_dirty >> PAGE_SHIFT); index++) {
page = find_or_create_page(inode->i_mapping, index, GFP_KERNEL);
if (!page) {
test_err("failed to allocate test page");
ret = -ENOMEM;
goto out;
}
SetPageDirty(page);
if (index) {
unlock_page(page);
} else {
get_page(page);
locked_page = page;
}
}
/* Test this scenario
* |--- delalloc ---|
* |--- search ---|
*/
set_extent_delalloc(tmp, 0, sectorsize - 1, 0, NULL);
start = 0;
end = 0;
found = find_lock_delalloc_range(inode, locked_page, &start,
&end);
if (!found) {
test_err("should have found at least one delalloc");
goto out_bits;
}
if (start != 0 || end != (sectorsize - 1)) {
test_err("expected start 0 end %u, got start %llu end %llu",
sectorsize - 1, start, end);
goto out_bits;
}
unlock_extent(tmp, start, end);
unlock_page(locked_page);
put_page(locked_page);
/*
* Test this scenario
*
* |--- delalloc ---|
* |--- search ---|
*/
test_start = SZ_64M;
locked_page = find_lock_page(inode->i_mapping,
test_start >> PAGE_SHIFT);
if (!locked_page) {
test_err("couldn't find the locked page");
goto out_bits;
}
set_extent_delalloc(tmp, sectorsize, max_bytes - 1, 0, NULL);
start = test_start;
end = 0;
found = find_lock_delalloc_range(inode, locked_page, &start,
&end);
if (!found) {
test_err("couldn't find delalloc in our range");
goto out_bits;
}
if (start != test_start || end != max_bytes - 1) {
test_err("expected start %llu end %llu, got start %llu, end %llu",
test_start, max_bytes - 1, start, end);
goto out_bits;
}
if (process_page_range(inode, start, end,
PROCESS_TEST_LOCKED | PROCESS_UNLOCK)) {
test_err("there were unlocked pages in the range");
goto out_bits;
}
unlock_extent(tmp, start, end);
/* locked_page was unlocked above */
put_page(locked_page);
/*
* Test this scenario
* |--- delalloc ---|
* |--- search ---|
*/
test_start = max_bytes + sectorsize;
locked_page = find_lock_page(inode->i_mapping, test_start >>
PAGE_SHIFT);
if (!locked_page) {
test_err("couldn't find the locked page");
goto out_bits;
}
start = test_start;
end = 0;
found = find_lock_delalloc_range(inode, locked_page, &start,
&end);
if (found) {
test_err("found range when we shouldn't have");
goto out_bits;
}
if (end != (u64)-1) {
test_err("did not return the proper end offset");
goto out_bits;
}
/*
* Test this scenario
* [------- delalloc -------|
* [max_bytes]|-- search--|
*
* We are re-using our test_start from above since it works out well.
*/
set_extent_delalloc(tmp, max_bytes, total_dirty - 1, 0, NULL);
start = test_start;
end = 0;
found = find_lock_delalloc_range(inode, locked_page, &start,
&end);
if (!found) {
test_err("didn't find our range");
goto out_bits;
}
if (start != test_start || end != total_dirty - 1) {
test_err("expected start %llu end %llu, got start %llu end %llu",
test_start, total_dirty - 1, start, end);
goto out_bits;
}
if (process_page_range(inode, start, end,
PROCESS_TEST_LOCKED | PROCESS_UNLOCK)) {
test_err("pages in range were not all locked");
goto out_bits;
}
unlock_extent(tmp, start, end);
/*
* Now to test where we run into a page that is no longer dirty in the
* range we want to find.
*/
page = find_get_page(inode->i_mapping,
(max_bytes + SZ_1M) >> PAGE_SHIFT);
if (!page) {
test_err("couldn't find our page");
goto out_bits;
}
ClearPageDirty(page);
put_page(page);
/* We unlocked it in the previous test */
lock_page(locked_page);
start = test_start;
end = 0;
/*
* Currently if we fail to find dirty pages in the delalloc range we
* will adjust max_bytes down to PAGE_SIZE and then re-search. If
* this changes at any point in the future we will need to fix this
* tests expected behavior.
*/
found = find_lock_delalloc_range(inode, locked_page, &start,
&end);
if (!found) {
test_err("didn't find our range");
goto out_bits;
}
if (start != test_start && end != test_start + PAGE_SIZE - 1) {
test_err("expected start %llu end %llu, got start %llu end %llu",
test_start, test_start + PAGE_SIZE - 1, start, end);
goto out_bits;
}
if (process_page_range(inode, start, end, PROCESS_TEST_LOCKED |
PROCESS_UNLOCK)) {
test_err("pages in range were not all locked");
goto out_bits;
}
ret = 0;
out_bits:
clear_extent_bits(tmp, 0, total_dirty - 1, (unsigned)-1);
out:
if (locked_page)
put_page(locked_page);
process_page_range(inode, 0, total_dirty - 1,
PROCESS_UNLOCK | PROCESS_RELEASE);
iput(inode);
return ret;
}
static int check_eb_bitmap(unsigned long *bitmap, struct extent_buffer *eb,
unsigned long len)
{
unsigned long i;
for (i = 0; i < len * BITS_PER_BYTE; i++) {
int bit, bit1;
bit = !!test_bit(i, bitmap);
bit1 = !!extent_buffer_test_bit(eb, 0, i);
if (bit1 != bit) {
test_err("bits do not match");
return -EINVAL;
}
bit1 = !!extent_buffer_test_bit(eb, i / BITS_PER_BYTE,
i % BITS_PER_BYTE);
if (bit1 != bit) {
test_err("offset bits do not match");
return -EINVAL;
}
}
return 0;
}
static int __test_eb_bitmaps(unsigned long *bitmap, struct extent_buffer *eb,
unsigned long len)
{
unsigned long i, j;
u32 x;
int ret;
memset(bitmap, 0, len);
memzero_extent_buffer(eb, 0, len);
if (memcmp_extent_buffer(eb, bitmap, 0, len) != 0) {
test_err("bitmap was not zeroed");
return -EINVAL;
}
bitmap_set(bitmap, 0, len * BITS_PER_BYTE);
extent_buffer_bitmap_set(eb, 0, 0, len * BITS_PER_BYTE);
ret = check_eb_bitmap(bitmap, eb, len);
if (ret) {
test_err("setting all bits failed");
return ret;
}
bitmap_clear(bitmap, 0, len * BITS_PER_BYTE);
extent_buffer_bitmap_clear(eb, 0, 0, len * BITS_PER_BYTE);
ret = check_eb_bitmap(bitmap, eb, len);
if (ret) {
test_err("clearing all bits failed");
return ret;
}
/* Straddling pages test */
if (len > PAGE_SIZE) {
bitmap_set(bitmap,
(PAGE_SIZE - sizeof(long) / 2) * BITS_PER_BYTE,
sizeof(long) * BITS_PER_BYTE);
extent_buffer_bitmap_set(eb, PAGE_SIZE - sizeof(long) / 2, 0,
sizeof(long) * BITS_PER_BYTE);
ret = check_eb_bitmap(bitmap, eb, len);
if (ret) {
test_err("setting straddling pages failed");
return ret;
}
bitmap_set(bitmap, 0, len * BITS_PER_BYTE);
bitmap_clear(bitmap,
(PAGE_SIZE - sizeof(long) / 2) * BITS_PER_BYTE,
sizeof(long) * BITS_PER_BYTE);
extent_buffer_bitmap_set(eb, 0, 0, len * BITS_PER_BYTE);
extent_buffer_bitmap_clear(eb, PAGE_SIZE - sizeof(long) / 2, 0,
sizeof(long) * BITS_PER_BYTE);
ret = check_eb_bitmap(bitmap, eb, len);
if (ret) {
test_err("clearing straddling pages failed");
return ret;
}
}
/*
* Generate a wonky pseudo-random bit pattern for the sake of not using
* something repetitive that could miss some hypothetical off-by-n bug.
*/
x = 0;
bitmap_clear(bitmap, 0, len * BITS_PER_BYTE);
extent_buffer_bitmap_clear(eb, 0, 0, len * BITS_PER_BYTE);
for (i = 0; i < len * BITS_PER_BYTE / 32; i++) {
x = (0x19660dULL * (u64)x + 0x3c6ef35fULL) & 0xffffffffU;
for (j = 0; j < 32; j++) {
if (x & (1U << j)) {
bitmap_set(bitmap, i * 32 + j, 1);
extent_buffer_bitmap_set(eb, 0, i * 32 + j, 1);
}
}
}
ret = check_eb_bitmap(bitmap, eb, len);
if (ret) {
test_err("random bit pattern failed");
return ret;
}
return 0;
}
static int test_eb_bitmaps(u32 sectorsize, u32 nodesize)
{
struct btrfs_fs_info *fs_info;
unsigned long len;
unsigned long *bitmap = NULL;
struct extent_buffer *eb = NULL;
int ret;
test_msg("running extent buffer bitmap tests");
/*
* In ppc64, sectorsize can be 64K, thus 4 * 64K will be larger than
* BTRFS_MAX_METADATA_BLOCKSIZE.
*/
len = (sectorsize < BTRFS_MAX_METADATA_BLOCKSIZE)
? sectorsize * 4 : sectorsize;
fs_info = btrfs_alloc_dummy_fs_info(len, len);
if (!fs_info) {
test_std_err(TEST_ALLOC_FS_INFO);
return -ENOMEM;
}
bitmap = kmalloc(len, GFP_KERNEL);
if (!bitmap) {
test_err("couldn't allocate test bitmap");
ret = -ENOMEM;
goto out;
}
eb = __alloc_dummy_extent_buffer(fs_info, 0, len);
if (!eb) {
test_std_err(TEST_ALLOC_ROOT);
ret = -ENOMEM;
goto out;
}
ret = __test_eb_bitmaps(bitmap, eb, len);
if (ret)
goto out;
/* Do it over again with an extent buffer which isn't page-aligned. */
free_extent_buffer(eb);
eb = __alloc_dummy_extent_buffer(fs_info, nodesize / 2, len);
if (!eb) {
test_std_err(TEST_ALLOC_ROOT);
ret = -ENOMEM;
goto out;
}
ret = __test_eb_bitmaps(bitmap, eb, len);
out:
free_extent_buffer(eb);
kfree(bitmap);
btrfs_free_dummy_fs_info(fs_info);
return ret;
}
static int test_find_first_clear_extent_bit(void)
{
struct extent_io_tree tree;
u64 start, end;
int ret = -EINVAL;
test_msg("running find_first_clear_extent_bit test");
extent_io_tree_init(NULL, &tree, IO_TREE_SELFTEST, NULL);
/*
* Set 1M-4M alloc/discard and 32M-64M thus leaving a hole between
* 4M-32M
*/
set_extent_bits(&tree, SZ_1M, SZ_4M - 1,
CHUNK_TRIMMED | CHUNK_ALLOCATED);
find_first_clear_extent_bit(&tree, SZ_512K, &start, &end,
CHUNK_TRIMMED | CHUNK_ALLOCATED);
if (start != 0 || end != SZ_1M - 1) {
test_err("error finding beginning range: start %llu end %llu",
start, end);
goto out;
}
/* Now add 32M-64M so that we have a hole between 4M-32M */
set_extent_bits(&tree, SZ_32M, SZ_64M - 1,
CHUNK_TRIMMED | CHUNK_ALLOCATED);
/*
* Request first hole starting at 12M, we should get 4M-32M
*/
find_first_clear_extent_bit(&tree, 12 * SZ_1M, &start, &end,
CHUNK_TRIMMED | CHUNK_ALLOCATED);
if (start != SZ_4M || end != SZ_32M - 1) {
test_err("error finding trimmed range: start %llu end %llu",
start, end);
goto out;
}
/*
* Search in the middle of allocated range, should get the next one
* available, which happens to be unallocated -> 4M-32M
*/
find_first_clear_extent_bit(&tree, SZ_2M, &start, &end,
CHUNK_TRIMMED | CHUNK_ALLOCATED);
if (start != SZ_4M || end != SZ_32M - 1) {
test_err("error finding next unalloc range: start %llu end %llu",
start, end);
goto out;
}
/*
* Set 64M-72M with CHUNK_ALLOC flag, then search for CHUNK_TRIMMED flag
* being unset in this range, we should get the entry in range 64M-72M
*/
set_extent_bits(&tree, SZ_64M, SZ_64M + SZ_8M - 1, CHUNK_ALLOCATED);
find_first_clear_extent_bit(&tree, SZ_64M + SZ_1M, &start, &end,
CHUNK_TRIMMED);
if (start != SZ_64M || end != SZ_64M + SZ_8M - 1) {
test_err("error finding exact range: start %llu end %llu",
start, end);
goto out;
}
find_first_clear_extent_bit(&tree, SZ_64M - SZ_8M, &start, &end,
CHUNK_TRIMMED);
/*
* Search in the middle of set range whose immediate neighbour doesn't
* have the bits set so it must be returned
*/
if (start != SZ_64M || end != SZ_64M + SZ_8M - 1) {
test_err("error finding next alloc range: start %llu end %llu",
start, end);
goto out;
}
/*
* Search beyond any known range, shall return after last known range
* and end should be -1
*/
find_first_clear_extent_bit(&tree, -1, &start, &end, CHUNK_TRIMMED);
if (start != SZ_64M + SZ_8M || end != -1) {
test_err(
"error handling beyond end of range search: start %llu end %llu",
start, end);
goto out;
}
ret = 0;
out:
clear_extent_bits(&tree, 0, (u64)-1, CHUNK_TRIMMED | CHUNK_ALLOCATED);
return ret;
}
int btrfs_test_extent_io(u32 sectorsize, u32 nodesize)
{
int ret;
test_msg("running extent I/O tests");
ret = test_find_delalloc(sectorsize);
if (ret)
goto out;
ret = test_find_first_clear_extent_bit();
if (ret)
goto out;
ret = test_eb_bitmaps(sectorsize, nodesize);
out:
return ret;
}