Commit 0f331229 authored by Omar Sandoval's avatar Omar Sandoval Committed by Chris Mason
Browse files

Btrfs: add extent buffer bitmap sanity tests 



Sanity test the extent buffer bitmap operations (test, set, and clear)
against the equivalent standard kernel operations.

Signed-off-by: default avatarOmar Sandoval <osandov@fb.com>
Signed-off-by: default avatarChris Mason <clm@fb.com>
parent 3e1e8bb7

fs/btrfs/extent_io.c

+21 −13
Original line number Diff line number Diff line
@@ -4730,24 +4730,14 @@ struct extent_buffer *btrfs_clone_extent_buffer(struct extent_buffer *src) 
	return new;

}



struct extent_buffer *alloc_dummy_extent_buffer(struct btrfs_fs_info *fs_info,

						u64 start)

struct extent_buffer *__alloc_dummy_extent_buffer(struct btrfs_fs_info *fs_info,

						  u64 start, unsigned long len)

{

	struct extent_buffer *eb;

	unsigned long len;

	unsigned long num_pages;

	unsigned long i;



	if (!fs_info) {

		/*

		 * Called only from tests that don't always have a fs_info

		 * available, but we know that nodesize is 4096

		 */

		len = 4096;

	} else {

		len = fs_info->tree_root->nodesize;

	}

	num_pages = num_extent_pages(0, len);

	num_pages = num_extent_pages(start, len);



	eb = __alloc_extent_buffer(fs_info, start, len);

	if (!eb)
@@ -4770,6 +4760,24 @@ struct extent_buffer *alloc_dummy_extent_buffer(struct btrfs_fs_info *fs_info, 
	return NULL;

}



struct extent_buffer *alloc_dummy_extent_buffer(struct btrfs_fs_info *fs_info,

						u64 start)

{

	unsigned long len;



	if (!fs_info) {

		/*

		 * Called only from tests that don't always have a fs_info

		 * available, but we know that nodesize is 4096

		 */

		len = 4096;

	} else {

		len = fs_info->tree_root->nodesize;

	}



	return __alloc_dummy_extent_buffer(fs_info, start, len);

}



static void check_buffer_tree_ref(struct extent_buffer *eb)

{

	int refs;

fs/btrfs/extent_io.h

+3 −1
Original line number Diff line number Diff line
@@ -263,6 +263,8 @@ void set_page_extent_mapped(struct page *page); 


struct extent_buffer *alloc_extent_buffer(struct btrfs_fs_info *fs_info,

					  u64 start);

struct extent_buffer *__alloc_dummy_extent_buffer(struct btrfs_fs_info *fs_info,

						  u64 start, unsigned long len);

struct extent_buffer *alloc_dummy_extent_buffer(struct btrfs_fs_info *fs_info,

						u64 start);

struct extent_buffer *btrfs_clone_extent_buffer(struct extent_buffer *src);

fs/btrfs/tests/extent-io-tests.c

+136 −2
Original line number Diff line number Diff line
@@ -18,6 +18,7 @@ 


#include <linux/pagemap.h>

#include <linux/sched.h>

#include <linux/slab.h>

#include "btrfs-tests.h"

#include "../extent_io.h"
@@ -76,6 +77,8 @@ static int test_find_delalloc(void) 
	u64 found;

	int ret = -EINVAL;



	test_msg("Running find delalloc tests\n");



	inode = btrfs_new_test_inode();

	if (!inode) {

		test_msg("Failed to allocate test inode\n");
@@ -268,8 +271,139 @@ static int test_find_delalloc(void) 
	return ret;

}



static int __test_eb_bitmaps(unsigned long *bitmap, struct extent_buffer *eb,

			     unsigned long len)

{

	unsigned long i, x;



	memset(bitmap, 0, len);

	memset_extent_buffer(eb, 0, 0, len);

	if (memcmp_extent_buffer(eb, bitmap, 0, len) != 0) {

		test_msg("Bitmap was not zeroed\n");

		return -EINVAL;

	}



	bitmap_set(bitmap, 0, len * BITS_PER_BYTE);

	extent_buffer_bitmap_set(eb, 0, 0, len * BITS_PER_BYTE);

	if (memcmp_extent_buffer(eb, bitmap, 0, len) != 0) {

		test_msg("Setting all bits failed\n");

		return -EINVAL;

	}



	bitmap_clear(bitmap, 0, len * BITS_PER_BYTE);

	extent_buffer_bitmap_clear(eb, 0, 0, len * BITS_PER_BYTE);

	if (memcmp_extent_buffer(eb, bitmap, 0, len) != 0) {

		test_msg("Clearing all bits failed\n");

		return -EINVAL;

	}



	bitmap_set(bitmap, (PAGE_CACHE_SIZE - sizeof(long) / 2) * BITS_PER_BYTE,

		   sizeof(long) * BITS_PER_BYTE);

	extent_buffer_bitmap_set(eb, PAGE_CACHE_SIZE - sizeof(long) / 2, 0,

				 sizeof(long) * BITS_PER_BYTE);

	if (memcmp_extent_buffer(eb, bitmap, 0, len) != 0) {

		test_msg("Setting straddling pages failed\n");

		return -EINVAL;

	}



	bitmap_set(bitmap, 0, len * BITS_PER_BYTE);

	bitmap_clear(bitmap,

		     (PAGE_CACHE_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_CACHE_SIZE - sizeof(long) / 2, 0,

				   sizeof(long) * BITS_PER_BYTE);

	if (memcmp_extent_buffer(eb, bitmap, 0, len) != 0) {

		test_msg("Clearing straddling pages failed\n");

		return -EINVAL;

	}



	/*

	 * 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;

	for (i = 0; i < len / sizeof(long); i++) {

		x = (0x19660dULL * (u64)x + 0x3c6ef35fULL) & 0xffffffffUL;

		bitmap[i] = x;

	}

	write_extent_buffer(eb, bitmap, 0, len);



	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_msg("Testing bit pattern failed\n");

			return -EINVAL;

		}



		bit1 = !!extent_buffer_test_bit(eb, i / BITS_PER_BYTE,

						i % BITS_PER_BYTE);

		if (bit1 != bit) {

			test_msg("Testing bit pattern with offset failed\n");

			return -EINVAL;

		}

	}



	return 0;

}



static int test_eb_bitmaps(void)

{

	unsigned long len = PAGE_CACHE_SIZE * 4;

	unsigned long *bitmap;

	struct extent_buffer *eb;

	int ret;



	test_msg("Running extent buffer bitmap tests\n");



	bitmap = kmalloc(len, GFP_NOFS);

	if (!bitmap) {

		test_msg("Couldn't allocate test bitmap\n");

		return -ENOMEM;

	}



	eb = __alloc_dummy_extent_buffer(NULL, 0, len);

	if (!eb) {

		test_msg("Couldn't allocate test extent buffer\n");

		kfree(bitmap);

		return -ENOMEM;

	}



	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(NULL, PAGE_CACHE_SIZE / 2, len);

	if (!eb) {

		test_msg("Couldn't allocate test extent buffer\n");

		kfree(bitmap);

		return -ENOMEM;

	}



	ret = __test_eb_bitmaps(bitmap, eb, len);

out:

	free_extent_buffer(eb);

	kfree(bitmap);

	return ret;

}



int btrfs_test_extent_io(void)

{

	test_msg("Running find delalloc tests\n");

	return test_find_delalloc();

	int ret;



	test_msg("Running extent I/O tests\n");



	ret = test_find_delalloc();

	if (ret)

		goto out;



	ret = test_eb_bitmaps();

out:

	test_msg("Extent I/O tests finished\n");

	return ret;

}