fs/btrfs/tests/extent-io-tests.c - linux/kernel/git/gregkh/usb - Git at Google

 // 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);

 	/* Test correct handling of empty tree */
 	find_first_clear_extent_bit(&tree, 0, &start, &end, CHUNK_TRIMMED);
 	if (start != 0 || end != -1) {
 		test_err(
 	"error getting a range from completely empty tree: start %llu end %llu",
 			 start, end);
 		goto out;
 	}
 	/*
 	 * 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;
 }
	// 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);

	/* Test correct handling of empty tree */
	find_first_clear_extent_bit(&tree, 0, &start, &end, CHUNK_TRIMMED);
	if (start != 0 \|\| end != -1) {
	test_err(
	"error getting a range from completely empty tree: start %llu end %llu",
	start, end);
	goto out;
	}
	/*
	* 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;
	}