ftrace: Synchronize the initialization of ftrace_opsgrafted

There's some internal state that ftrace_ops needs to have set, but since
it can be declared outside of the ftrace.c code, it calls
ftrace_ops_init() on the ops in every global function. The issue is that
if two tasks call it on the same ops at the same time it is possible to
have the initialization of one corrupt the initialization of the other
call.

Create a ops_mutex to use to synchronize every initialization of the
ftrace_ops. The mutex is taken within checking the ftrace_ops flag that
states it was initializied but the flag is checked again after the mutex
has been taken. Checking first outside the mutex allows it to shortcut
having to take the mutex. But then the check needs to be done again after
the mute is taken in case of races.

Cc: stable@vger.kernel.org
Link: https://patch.msgid.link/20260902095501.6b59af20@gandalf.local.home
Fixes: f04f24fb7e48d ("ftrace, kprobes: Fix a deadlock on ftrace_regex_lock")
Reported-by: sashiko-bot@kernel.org
Close: https://lore.kernel.org/all/20260829025528.49A831F000E9@smtp.kernel.org/
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

1 files changed, 1095 insertions, 0 deletions

diff --git a/fs/btrfs/tests/inode-tests.c b/fs/btrfs/tests/inode-tests.c
new file mode 100644
index 000000000..b04fbcaf0
--- /dev/null
+++ b/fs/btrfs/tests/inode-tests.c
@@ -0,0 +1,1095 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2013 Fusion IO.  All rights reserved.
+ */
+
+#include <linux/types.h>
+#include "btrfs-tests.h"
+#include "../ctree.h"
+#include "../btrfs_inode.h"
+#include "../disk-io.h"
+#include "../extent_io.h"
+#include "../volumes.h"
+#include "../compression.h"
+#include "../accessors.h"
+
+static void insert_extent(struct btrfs_root *root, u64 start, u64 len,
+			  u64 ram_bytes, u64 offset, u64 disk_bytenr,
+			  u64 disk_len, u32 type, u8 compression, int slot)
+{
+	struct btrfs_path path;
+	struct btrfs_file_extent_item *fi;
+	struct extent_buffer *leaf = root->node;
+	struct btrfs_key key;
+	u32 value_len = sizeof(struct btrfs_file_extent_item);
+
+	if (type == BTRFS_FILE_EXTENT_INLINE)
+		value_len += len;
+	memset(&path, 0, sizeof(path));
+
+	path.nodes[0] = leaf;
+	path.slots[0] = slot;
+
+	key.objectid = BTRFS_FIRST_FREE_OBJECTID;
+	key.type = BTRFS_EXTENT_DATA_KEY;
+	key.offset = start;
+
+	/*
+	 * Passing a NULL trans handle is fine here, we have a dummy root eb
+	 * and the tree is a single node (level 0).
+	 */
+	btrfs_setup_item_for_insert(NULL, root, &path, &key, value_len);
+	fi = btrfs_item_ptr(leaf, slot, struct btrfs_file_extent_item);
+	btrfs_set_file_extent_generation(leaf, fi, 1);
+	btrfs_set_file_extent_type(leaf, fi, type);
+	btrfs_set_file_extent_disk_bytenr(leaf, fi, disk_bytenr);
+	btrfs_set_file_extent_disk_num_bytes(leaf, fi, disk_len);
+	btrfs_set_file_extent_offset(leaf, fi, offset);
+	btrfs_set_file_extent_num_bytes(leaf, fi, len);
+	btrfs_set_file_extent_ram_bytes(leaf, fi, ram_bytes);
+	btrfs_set_file_extent_compression(leaf, fi, compression);
+	btrfs_set_file_extent_encryption(leaf, fi, 0);
+	btrfs_set_file_extent_other_encoding(leaf, fi, 0);
+}
+
+static void insert_inode_item_key(struct btrfs_root *root)
+{
+	struct btrfs_path path;
+	struct extent_buffer *leaf = root->node;
+	struct btrfs_key key;
+	u32 value_len = 0;
+
+	memset(&path, 0, sizeof(path));
+
+	path.nodes[0] = leaf;
+	path.slots[0] = 0;
+
+	key.objectid = BTRFS_INODE_ITEM_KEY;
+	key.type = BTRFS_INODE_ITEM_KEY;
+	key.offset = 0;
+
+	/*
+	 * Passing a NULL trans handle is fine here, we have a dummy root eb
+	 * and the tree is a single node (level 0).
+	 */
+	btrfs_setup_item_for_insert(NULL, root, &path, &key, value_len);
+}
+
+/*
+ * Build the most complicated map of extents the earth has ever seen.  We want
+ * this so we can test all of the corner cases of btrfs_get_extent.  Here is a
+ * diagram of how the extents will look though this may not be possible we still
+ * want to make sure everything acts normally (the last number is not inclusive)
+ *
+ * The numbers are using 4K fs block size as an example, the real test will scale
+ * all the extent maps (except the inlined one) according to the block size.
+ *
+ * [ 0  - 6 ][ 6 - 4K       ][ 4K - 8K ][ 8K -  12K      ]
+ * [ inline ][ implied hole ][ regular ][ regular1 split ]
+ *
+ * [ 12K - 16K ][ 16K - 24K      ][ 24K - 28K ][ 28K - 32K ][ 32K - 36K         ]
+ * [ hole      ][ regular1 split ][ prealloc  ][ prealloc1 ][ prealloc1 written ]
+ *
+ * [ 36K - 44K ][ 44K - 52K  ][ 52K - 56K   ][ 56K - 60K ][ 60K - 68 K  ]
+ * [ prealloc1 ][ compressed ][ compressed1 ][ regular   ][ compressed1 ]
+ *
+ * [ 68K - 72K ][ 72K - 84K          ][ 84K - 88K ]
+ * [  regular  ][ hole but no extent ][ regular   ]
+ */
+static void setup_file_extents(struct btrfs_root *root, u32 sectorsize)
+{
+	int slot = 0;
+	u64 disk_bytenr = SZ_1M;
+	u64 offset = 0;
+
+	/*
+	 * Start 0, length 6, inlined.
+	 *
+	 * Tree-checker has strict limits on inline extents that they can only
+	 * exist at file offset 0, thus we can only have one inline file extent
+	 * at most.
+	 */
+	insert_extent(root, offset, 6, 6, 0, 0, 0, BTRFS_FILE_EXTENT_INLINE, 0,
+		      slot);
+	slot++;
+	offset = sectorsize;
+
+	/* Start 1 * blocksize, length 1 * blocksize, regular. */
+	insert_extent(root, offset, sectorsize, sectorsize, 0,
+		      disk_bytenr, sectorsize, BTRFS_FILE_EXTENT_REG, 0, slot);
+	slot++;
+
+	/* We don't want the regular em merged with the next one. */
+	disk_bytenr += 2 * sectorsize;
+	offset += sectorsize;
+
+	/*
+	 * Start 2 * blocksize, length 1 * blocksize, regular.
+	 *
+	 * Now for 3 extents that were split from a hole punch so we test
+	 * offsets properly.
+	 */
+	insert_extent(root, offset, sectorsize, 4 * sectorsize, 0, disk_bytenr,
+		      4 * sectorsize, BTRFS_FILE_EXTENT_REG, 0, slot);
+	slot++;
+	offset += sectorsize;
+
+	/* Start 3 * blocksize, length 1 * blocksize, regular, explicit hole. */
+	insert_extent(root, offset, sectorsize, sectorsize, 0, 0, 0,
+		      BTRFS_FILE_EXTENT_REG, 0, slot);
+	slot++;
+	offset += sectorsize;
+
+	/* Start 4 * blocksize, length 2 * blocksize, regular. */
+	insert_extent(root, offset, 2 * sectorsize, 4 * sectorsize,
+		      2 * sectorsize, disk_bytenr, 4 * sectorsize,
+		      BTRFS_FILE_EXTENT_REG, 0, slot);
+	slot++;
+	offset += 2 * sectorsize;
+	disk_bytenr += 4 * sectorsize;
+
+	/* Start 6 * blocksize, length 1 * blocksize, preallocated. */
+	insert_extent(root, offset, sectorsize, sectorsize, 0, disk_bytenr,
+		sectorsize, BTRFS_FILE_EXTENT_PREALLOC, 0, slot);
+	slot++;
+	offset += sectorsize;
+
+	/*
+	 * We want to jack up disk_bytenr a little more so the em stuff doesn't
+	 * merge our records.
+	 */
+	disk_bytenr += 2 * sectorsize;
+
+	/*
+	 * Start 7 * blocksize, length 1 * blocksize, prealloc.
+	 *
+	 * Now for a partially written prealloc extent, basically the same as
+	 * the hole punch example above.  Ram_bytes never changes when you mark
+	 * extents written btw.
+	 */
+	insert_extent(root, offset, sectorsize, 4 * sectorsize, 0, disk_bytenr,
+		      4 * sectorsize, BTRFS_FILE_EXTENT_PREALLOC, 0, slot);
+	slot++;
+	offset += sectorsize;
+
+	/* Start 8 * blocksize, length 1 * blocksize, regular. */
+	insert_extent(root, offset, sectorsize, 4 * sectorsize, sectorsize,
+		      disk_bytenr, 4 * sectorsize, BTRFS_FILE_EXTENT_REG, 0,
+		      slot);
+	slot++;
+	offset += sectorsize;
+
+	/* Start 9 * blocksize, length 2 * blocksize, prealloc. */
+	insert_extent(root, offset, 2 * sectorsize, 4 * sectorsize,
+		      2 * sectorsize, disk_bytenr, 4 * sectorsize,
+		      BTRFS_FILE_EXTENT_PREALLOC, 0, slot);
+	slot++;
+	offset += 2 * sectorsize;
+	disk_bytenr += 4 * sectorsize;
+
+	/* Start 11 * blocksize, length 2 * blocksize, regular. */
+	insert_extent(root, offset, 2 * sectorsize, 2 * sectorsize, 0,
+		      disk_bytenr, sectorsize, BTRFS_FILE_EXTENT_REG,
+		      BTRFS_COMPRESS_ZLIB, slot);
+	slot++;
+	offset += 2 * sectorsize;
+	/* No merges */
+	disk_bytenr += 2 * sectorsize;
+
+	/* Start 13 * blocksize, length 1 * blocksize, regular. */
+	insert_extent(root, offset, sectorsize, 4 * sectorsize, 0, disk_bytenr,
+		      sectorsize, BTRFS_FILE_EXTENT_REG,
+		      BTRFS_COMPRESS_ZLIB, slot);
+	slot++;
+	offset += sectorsize;
+
+	/* Start 14 * blocksize, length 1 * blocksize, regular. */
+	insert_extent(root, offset, sectorsize, sectorsize, 0,
+		      disk_bytenr + sectorsize, sectorsize,
+		      BTRFS_FILE_EXTENT_REG, 0, slot);
+	slot++;
+	offset += sectorsize;
+
+	/* Start 15 * blocksize, length 2 * blocksize, regular. */
+	insert_extent(root, offset, 2 * sectorsize, 4 * sectorsize,
+		      2 * sectorsize, disk_bytenr, sectorsize,
+		      BTRFS_FILE_EXTENT_REG, BTRFS_COMPRESS_ZLIB, slot);
+	slot++;
+	offset += 2 * sectorsize;
+	disk_bytenr += 2 * sectorsize;
+
+	/* Start 17 * blocksize, length 1 * blocksize, regular. */
+	insert_extent(root, offset, sectorsize, sectorsize, 0, disk_bytenr,
+		      sectorsize, BTRFS_FILE_EXTENT_REG, 0, slot);
+	slot++;
+	offset += 4 * sectorsize;
+	disk_bytenr += sectorsize;
+
+	/*
+	 * Start 18 * blocksize, length 3 * blocksize, implied hole (aka no
+	 * file extent item).
+	 *
+	 * Start 21 * blocksize, length 1 * blocksize, regular.
+	 */
+	insert_extent(root, offset, sectorsize, sectorsize, 0, disk_bytenr,
+		      sectorsize, BTRFS_FILE_EXTENT_REG, 0, slot);
+}
+
+static u32 prealloc_only = 0;
+static u32 compressed_only = 0;
+static u32 vacancy_only = 0;
+
+static noinline int test_btrfs_get_extent(u32 sectorsize, u32 nodesize)
+{
+	struct btrfs_fs_info *fs_info = NULL;
+	struct inode *inode = NULL;
+	struct btrfs_root *root = NULL;
+	struct extent_map *em = NULL;
+	u64 orig_start;
+	u64 disk_bytenr;
+	u64 offset;
+	int ret = -ENOMEM;
+
+	test_msg("running btrfs_get_extent tests");
+
+	inode = btrfs_new_test_inode();
+	if (!inode) {
+		test_std_err(TEST_ALLOC_INODE);
+		return ret;
+	}
+
+	fs_info = btrfs_alloc_dummy_fs_info(nodesize, sectorsize);
+	if (!fs_info) {
+		test_std_err(TEST_ALLOC_FS_INFO);
+		goto out;
+	}
+
+	root = btrfs_alloc_dummy_root(fs_info);
+	if (IS_ERR(root)) {
+		test_std_err(TEST_ALLOC_ROOT);
+		goto out;
+	}
+
+	root->node = alloc_dummy_extent_buffer(fs_info, nodesize);
+	if (!root->node) {
+		test_std_err(TEST_ALLOC_ROOT);
+		goto out;
+	}
+
+	btrfs_set_header_nritems(root->node, 0);
+	btrfs_set_header_level(root->node, 0);
+	ret = -EINVAL;
+
+	/* First with no extents */
+	BTRFS_I(inode)->root = root;
+	em = btrfs_get_extent(BTRFS_I(inode), NULL, 0, sectorsize);
+	if (IS_ERR(em)) {
+		em = NULL;
+		test_err("got an error when we shouldn't have");
+		goto out;
+	}
+	if (em->disk_bytenr != EXTENT_MAP_HOLE) {
+		test_err("expected a hole, got %llu", em->disk_bytenr);
+		goto out;
+	}
+	btrfs_free_extent_map(em);
+	btrfs_drop_extent_map_range(BTRFS_I(inode), 0, (u64)-1, false);
+
+	/*
+	 * All of the magic numbers are based on the mapping setup in
+	 * setup_file_extents, so if you change anything there you need to
+	 * update the comment and update the expected values below.
+	 */
+	setup_file_extents(root, sectorsize);
+
+	em = btrfs_get_extent(BTRFS_I(inode), NULL, 0, (u64)-1);
+	if (IS_ERR(em)) {
+		test_err("got an error when we shouldn't have");
+		goto out;
+	}
+	if (em->disk_bytenr != EXTENT_MAP_INLINE) {
+		test_err("expected an inline, got %llu", em->disk_bytenr);
+		goto out;
+	}
+
+	/*
+	 * For inline extent, we always round up the em to sectorsize, as
+	 * they are either:
+	 *
+	 * a) a hidden hole
+	 *    The range will be zeroed at inline extent read time.
+	 *
+	 * b) a file extent with unaligned bytenr
+	 *    Tree checker will reject it.
+	 */
+	if (em->start != 0 || em->len != sectorsize) {
+		test_err(
+	"unexpected extent wanted start 0 len %u, got start %llu len %llu",
+			sectorsize, em->start, em->len);
+		goto out;
+	}
+	if (em->flags != 0) {
+		test_err("unexpected flags set, want 0 have %u", em->flags);
+		goto out;
+	}
+	/*
+	 * We don't test anything else for inline since it doesn't get set
+	 * unless we have a page for it to write into.  Maybe we should change
+	 * this?
+	 */
+	offset = btrfs_extent_map_end(em);
+	btrfs_free_extent_map(em);
+
+	/* Regular extent */
+	em = btrfs_get_extent(BTRFS_I(inode), NULL, offset, sectorsize);
+	if (IS_ERR(em)) {
+		test_err("got an error when we shouldn't have");
+		goto out;
+	}
+	if (em->disk_bytenr >= EXTENT_MAP_LAST_BYTE) {
+		test_err("expected a real extent, got %llu", em->disk_bytenr);
+		goto out;
+	}
+	if (em->start != offset || em->len != sectorsize) {
+		test_err(
+	"unexpected extent wanted start %llu len %u, got start %llu len %llu",
+			offset, sectorsize, em->start, em->len);
+		goto out;
+	}
+	if (em->flags != 0) {
+		test_err("unexpected flags set, want 0 have %u", em->flags);
+		goto out;
+	}
+	if (em->offset != 0) {
+		test_err("wrong offset, want 0, have %llu", em->offset);
+		goto out;
+	}
+	offset = btrfs_extent_map_end(em);
+	btrfs_free_extent_map(em);
+
+	/* The next 3 are split extents */
+	em = btrfs_get_extent(BTRFS_I(inode), NULL, offset, sectorsize);
+	if (IS_ERR(em)) {
+		test_err("got an error when we shouldn't have");
+		goto out;
+	}
+	if (em->disk_bytenr >= EXTENT_MAP_LAST_BYTE) {
+		test_err("expected a real extent, got %llu", em->disk_bytenr);
+		goto out;
+	}
+	if (em->start != offset || em->len != sectorsize) {
+		test_err(
+		"unexpected extent start %llu len %u, got start %llu len %llu",
+			offset, sectorsize, em->start, em->len);
+		goto out;
+	}
+	if (em->flags != 0) {
+		test_err("unexpected flags set, want 0 have %u", em->flags);
+		goto out;
+	}
+	if (em->offset != 0) {
+		test_err("wrong offset, want 0, have %llu", em->offset);
+		goto out;
+	}
+	disk_bytenr = btrfs_extent_map_block_start(em);
+	orig_start = em->start;
+	offset = btrfs_extent_map_end(em);
+	btrfs_free_extent_map(em);
+
+	em = btrfs_get_extent(BTRFS_I(inode), NULL, offset, sectorsize);
+	if (IS_ERR(em)) {
+		test_err("got an error when we shouldn't have");
+		goto out;
+	}
+	if (em->disk_bytenr != EXTENT_MAP_HOLE) {
+		test_err("expected a hole, got %llu", em->disk_bytenr);
+		goto out;
+	}
+	if (em->start != offset || em->len != sectorsize) {
+		test_err(
+	"unexpected extent wanted start %llu len %u, got start %llu len %llu",
+			offset, sectorsize, em->start, em->len);
+		goto out;
+	}
+	if (em->flags != 0) {
+		test_err("unexpected flags set, want 0 have %u", em->flags);
+		goto out;
+	}
+	offset = btrfs_extent_map_end(em);
+	btrfs_free_extent_map(em);
+
+	em = btrfs_get_extent(BTRFS_I(inode), NULL, offset, sectorsize);
+	if (IS_ERR(em)) {
+		test_err("got an error when we shouldn't have");
+		goto out;
+	}
+	if (em->disk_bytenr >= EXTENT_MAP_LAST_BYTE) {
+		test_err("expected a real extent, got %llu", em->disk_bytenr);
+		goto out;
+	}
+	if (em->start != offset || em->len != 2 * sectorsize) {
+		test_err(
+	"unexpected extent wanted start %llu len %u, got start %llu len %llu",
+			offset, 2 * sectorsize, em->start, em->len);
+		goto out;
+	}
+	if (em->flags != 0) {
+		test_err("unexpected flags set, want 0 have %u", em->flags);
+		goto out;
+	}
+	if (em->start - em->offset != orig_start) {
+		test_err("wrong offset, em->start=%llu em->offset=%llu orig_start=%llu",
+			 em->start, em->offset, orig_start);
+		goto out;
+	}
+	disk_bytenr += (em->start - orig_start);
+	if (btrfs_extent_map_block_start(em) != disk_bytenr) {
+		test_err("wrong block start, want %llu, have %llu",
+			 disk_bytenr, btrfs_extent_map_block_start(em));
+		goto out;
+	}
+	offset = btrfs_extent_map_end(em);
+	btrfs_free_extent_map(em);
+
+	/* Prealloc extent */
+	em = btrfs_get_extent(BTRFS_I(inode), NULL, offset, sectorsize);
+	if (IS_ERR(em)) {
+		test_err("got an error when we shouldn't have");
+		goto out;
+	}
+	if (em->disk_bytenr >= EXTENT_MAP_LAST_BYTE) {
+		test_err("expected a real extent, got %llu", em->disk_bytenr);
+		goto out;
+	}
+	if (em->start != offset || em->len != sectorsize) {
+		test_err(
+	"unexpected extent wanted start %llu len %u, got start %llu len %llu",
+			offset, sectorsize, em->start, em->len);
+		goto out;
+	}
+	if (em->flags != prealloc_only) {
+		test_err("unexpected flags set, want %u have %u",
+			 prealloc_only, em->flags);
+		goto out;
+	}
+	if (em->offset != 0) {
+		test_err("wrong offset, want 0, have %llu", em->offset);
+		goto out;
+	}
+	offset = btrfs_extent_map_end(em);
+	btrfs_free_extent_map(em);
+
+	/* The next 3 are a half written prealloc extent */
+	em = btrfs_get_extent(BTRFS_I(inode), NULL, offset, sectorsize);
+	if (IS_ERR(em)) {
+		test_err("got an error when we shouldn't have");
+		goto out;
+	}
+	if (em->disk_bytenr >= EXTENT_MAP_LAST_BYTE) {
+		test_err("expected a real extent, got %llu", em->disk_bytenr);
+		goto out;
+	}
+	if (em->start != offset || em->len != sectorsize) {
+		test_err(
+	"unexpected extent wanted start %llu len %u, got start %llu len %llu",
+			offset, sectorsize, em->start, em->len);
+		goto out;
+	}
+	if (em->flags != prealloc_only) {
+		test_err("unexpected flags set, want %u have %u",
+			 prealloc_only, em->flags);
+		goto out;
+	}
+	if (em->offset != 0) {
+		test_err("wrong offset, want 0, have %llu", em->offset);
+		goto out;
+	}
+	disk_bytenr = btrfs_extent_map_block_start(em);
+	orig_start = em->start;
+	offset = btrfs_extent_map_end(em);
+	btrfs_free_extent_map(em);
+
+	em = btrfs_get_extent(BTRFS_I(inode), NULL, offset, sectorsize);
+	if (IS_ERR(em)) {
+		test_err("got an error when we shouldn't have");
+		goto out;
+	}
+	if (em->disk_bytenr >= EXTENT_MAP_HOLE) {
+		test_err("expected a real extent, got %llu", em->disk_bytenr);
+		goto out;
+	}
+	if (em->start != offset || em->len != sectorsize) {
+		test_err(
+	"unexpected extent wanted start %llu len %u, got start %llu len %llu",
+			offset, sectorsize, em->start, em->len);
+		goto out;
+	}
+	if (em->flags != 0) {
+		test_err("unexpected flags set, want 0 have %u", em->flags);
+		goto out;
+	}
+	if (em->start - em->offset != orig_start) {
+		test_err("unexpected offset, wanted %llu, have %llu",
+			 em->start - orig_start, em->offset);
+		goto out;
+	}
+	if (btrfs_extent_map_block_start(em) != disk_bytenr + em->offset) {
+		test_err("unexpected block start, wanted %llu, have %llu",
+			 disk_bytenr + em->offset, btrfs_extent_map_block_start(em));
+		goto out;
+	}
+	offset = btrfs_extent_map_end(em);
+	btrfs_free_extent_map(em);
+
+	em = btrfs_get_extent(BTRFS_I(inode), NULL, offset, sectorsize);
+	if (IS_ERR(em)) {
+		test_err("got an error when we shouldn't have");
+		goto out;
+	}
+	if (em->disk_bytenr >= EXTENT_MAP_LAST_BYTE) {
+		test_err("expected a real extent, got %llu", em->disk_bytenr);
+		goto out;
+	}
+	if (em->start != offset || em->len != 2 * sectorsize) {
+		test_err(
+	"unexpected extent wanted start %llu len %u, got start %llu len %llu",
+			offset, 2 * sectorsize, em->start, em->len);
+		goto out;
+	}
+	if (em->flags != prealloc_only) {
+		test_err("unexpected flags set, want %u have %u",
+			 prealloc_only, em->flags);
+		goto out;
+	}
+	if (em->start - em->offset != orig_start) {
+		test_err("wrong offset, em->start=%llu em->offset=%llu orig_start=%llu",
+			 em->start, em->offset, orig_start);
+		goto out;
+	}
+	if (btrfs_extent_map_block_start(em) != disk_bytenr + em->offset) {
+		test_err("unexpected block start, wanted %llu, have %llu",
+			 disk_bytenr + em->offset, btrfs_extent_map_block_start(em));
+		goto out;
+	}
+	offset = btrfs_extent_map_end(em);
+	btrfs_free_extent_map(em);
+
+	/* Now for the compressed extent */
+	em = btrfs_get_extent(BTRFS_I(inode), NULL, offset, sectorsize);
+	if (IS_ERR(em)) {
+		test_err("got an error when we shouldn't have");
+		goto out;
+	}
+	if (em->disk_bytenr >= EXTENT_MAP_LAST_BYTE) {
+		test_err("expected a real extent, got %llu", em->disk_bytenr);
+		goto out;
+	}
+	if (em->start != offset || em->len != 2 * sectorsize) {
+		test_err(
+	"unexpected extent wanted start %llu len %u, got start %llu len %llu",
+			offset, 2 * sectorsize, em->start, em->len);
+		goto out;
+	}
+	if (em->flags != compressed_only) {
+		test_err("unexpected flags set, want %u have %u",
+			 compressed_only, em->flags);
+		goto out;
+	}
+	if (em->offset != 0) {
+		test_err("wrong offset, want 0, have %llu", em->offset);
+		goto out;
+	}
+	if (btrfs_extent_map_compression(em) != BTRFS_COMPRESS_ZLIB) {
+		test_err("unexpected compress type, wanted %d, got %d",
+			 BTRFS_COMPRESS_ZLIB, btrfs_extent_map_compression(em));
+		goto out;
+	}
+	offset = btrfs_extent_map_end(em);
+	btrfs_free_extent_map(em);
+
+	/* Split compressed extent */
+	em = btrfs_get_extent(BTRFS_I(inode), NULL, offset, sectorsize);
+	if (IS_ERR(em)) {
+		test_err("got an error when we shouldn't have");
+		goto out;
+	}
+	if (em->disk_bytenr >= EXTENT_MAP_LAST_BYTE) {
+		test_err("expected a real extent, got %llu", em->disk_bytenr);
+		goto out;
+	}
+	if (em->start != offset || em->len != sectorsize) {
+		test_err(
+	"unexpected extent wanted start %llu len %u, got start %llu len %llu",
+			offset, sectorsize, em->start, em->len);
+		goto out;
+	}
+	if (em->flags != compressed_only) {
+		test_err("unexpected flags set, want %u have %u",
+			 compressed_only, em->flags);
+		goto out;
+	}
+	if (em->offset != 0) {
+		test_err("wrong offset, want 0, have %llu", em->offset);
+		goto out;
+	}
+	if (btrfs_extent_map_compression(em) != BTRFS_COMPRESS_ZLIB) {
+		test_err("unexpected compress type, wanted %d, got %d",
+			 BTRFS_COMPRESS_ZLIB, btrfs_extent_map_compression(em));
+		goto out;
+	}
+	disk_bytenr = btrfs_extent_map_block_start(em);
+	orig_start = em->start;
+	offset = btrfs_extent_map_end(em);
+	btrfs_free_extent_map(em);
+
+	em = btrfs_get_extent(BTRFS_I(inode), NULL, offset, sectorsize);
+	if (IS_ERR(em)) {
+		test_err("got an error when we shouldn't have");
+		goto out;
+	}
+	if (em->disk_bytenr >= EXTENT_MAP_LAST_BYTE) {
+		test_err("expected a real extent, got %llu", em->disk_bytenr);
+		goto out;
+	}
+	if (em->start != offset || em->len != sectorsize) {
+		test_err(
+	"unexpected extent wanted start %llu len %u, got start %llu len %llu",
+			offset, sectorsize, em->start, em->len);
+		goto out;
+	}
+	if (em->flags != 0) {
+		test_err("unexpected flags set, want 0 have %u", em->flags);
+		goto out;
+	}
+	if (em->offset != 0) {
+		test_err("wrong offset, want 0, have %llu", em->offset);
+		goto out;
+	}
+	offset = btrfs_extent_map_end(em);
+	btrfs_free_extent_map(em);
+
+	em = btrfs_get_extent(BTRFS_I(inode), NULL, offset, sectorsize);
+	if (IS_ERR(em)) {
+		test_err("got an error when we shouldn't have");
+		goto out;
+	}
+	if (btrfs_extent_map_block_start(em) != disk_bytenr) {
+		test_err("block start does not match, want %llu got %llu",
+			 disk_bytenr, btrfs_extent_map_block_start(em));
+		goto out;
+	}
+	if (em->start != offset || em->len != 2 * sectorsize) {
+		test_err(
+	"unexpected extent wanted start %llu len %u, got start %llu len %llu",
+			offset, 2 * sectorsize, em->start, em->len);
+		goto out;
+	}
+	if (em->flags != compressed_only) {
+		test_err("unexpected flags set, want %u have %u",
+			 compressed_only, em->flags);
+		goto out;
+	}
+	if (em->start - em->offset != orig_start) {
+		test_err("wrong offset, em->start=%llu em->offset=%llu orig_start=%llu",
+			 em->start, em->offset, orig_start);
+		goto out;
+	}
+	if (btrfs_extent_map_compression(em) != BTRFS_COMPRESS_ZLIB) {
+		test_err("unexpected compress type, wanted %d, got %d",
+			 BTRFS_COMPRESS_ZLIB, btrfs_extent_map_compression(em));
+		goto out;
+	}
+	offset = btrfs_extent_map_end(em);
+	btrfs_free_extent_map(em);
+
+	/* A hole between regular extents but no hole extent */
+	em = btrfs_get_extent(BTRFS_I(inode), NULL, offset + 6, sectorsize);
+	if (IS_ERR(em)) {
+		test_err("got an error when we shouldn't have");
+		goto out;
+	}
+	if (em->disk_bytenr >= EXTENT_MAP_LAST_BYTE) {
+		test_err("expected a real extent, got %llu", em->disk_bytenr);
+		goto out;
+	}
+	if (em->start != offset || em->len != sectorsize) {
+		test_err(
+	"unexpected extent wanted start %llu len %u, got start %llu len %llu",
+			offset, sectorsize, em->start, em->len);
+		goto out;
+	}
+	if (em->flags != 0) {
+		test_err("unexpected flags set, want 0 have %u", em->flags);
+		goto out;
+	}
+	if (em->offset != 0) {
+		test_err("wrong offset, want 0, have %llu", em->offset);
+		goto out;
+	}
+	offset = btrfs_extent_map_end(em);
+	btrfs_free_extent_map(em);
+
+	em = btrfs_get_extent(BTRFS_I(inode), NULL, offset, SZ_4M);
+	if (IS_ERR(em)) {
+		test_err("got an error when we shouldn't have");
+		goto out;
+	}
+	if (em->disk_bytenr != EXTENT_MAP_HOLE) {
+		test_err("expected a hole extent, got %llu", em->disk_bytenr);
+		goto out;
+	}
+	/*
+	 * Currently we just return a length that we requested rather than the
+	 * length of the actual hole, if this changes we'll have to change this
+	 * test.
+	 */
+	if (em->start != offset || em->len != 3 * sectorsize) {
+		test_err(
+	"unexpected extent wanted start %llu len %u, got start %llu len %llu",
+			offset, 3 * sectorsize, em->start, em->len);
+		goto out;
+	}
+	if (em->flags != vacancy_only) {
+		test_err("unexpected flags set, want %u have %u",
+			 vacancy_only, em->flags);
+		goto out;
+	}
+	if (em->offset != 0) {
+		test_err("wrong offset, want 0, have %llu", em->offset);
+		goto out;
+	}
+	offset = btrfs_extent_map_end(em);
+	btrfs_free_extent_map(em);
+
+	em = btrfs_get_extent(BTRFS_I(inode), NULL, offset, sectorsize);
+	if (IS_ERR(em)) {
+		test_err("got an error when we shouldn't have");
+		goto out;
+	}
+	if (em->disk_bytenr >= EXTENT_MAP_LAST_BYTE) {
+		test_err("expected a real extent, got %llu", em->disk_bytenr);
+		goto out;
+	}
+	if (em->start != offset || em->len != sectorsize) {
+		test_err(
+	"unexpected extent wanted start %llu len %u, got start %llu len %llu",
+			offset, sectorsize, em->start, em->len);
+		goto out;
+	}
+	if (em->flags != 0) {
+		test_err("unexpected flags set, want 0 have %u", em->flags);
+		goto out;
+	}
+	if (em->offset != 0) {
+		test_err("wrong orig offset, want 0, have %llu", em->offset);
+		goto out;
+	}
+	ret = 0;
+out:
+	if (!IS_ERR(em))
+		btrfs_free_extent_map(em);
+	iput(inode);
+	btrfs_free_dummy_root(root);
+	btrfs_free_dummy_fs_info(fs_info);
+	return ret;
+}
+
+static int test_hole_first(u32 sectorsize, u32 nodesize)
+{
+	struct btrfs_fs_info *fs_info = NULL;
+	struct inode *inode = NULL;
+	struct btrfs_root *root = NULL;
+	struct extent_map *em = NULL;
+	int ret = -ENOMEM;
+
+	test_msg("running hole first btrfs_get_extent test");
+
+	inode = btrfs_new_test_inode();
+	if (!inode) {
+		test_std_err(TEST_ALLOC_INODE);
+		return ret;
+	}
+
+	fs_info = btrfs_alloc_dummy_fs_info(nodesize, sectorsize);
+	if (!fs_info) {
+		test_std_err(TEST_ALLOC_FS_INFO);
+		goto out;
+	}
+
+	root = btrfs_alloc_dummy_root(fs_info);
+	if (IS_ERR(root)) {
+		test_std_err(TEST_ALLOC_ROOT);
+		goto out;
+	}
+
+	root->node = alloc_dummy_extent_buffer(fs_info, nodesize);
+	if (!root->node) {
+		test_std_err(TEST_ALLOC_ROOT);
+		goto out;
+	}
+
+	btrfs_set_header_nritems(root->node, 0);
+	btrfs_set_header_level(root->node, 0);
+	BTRFS_I(inode)->root = root;
+	ret = -EINVAL;
+
+	/*
+	 * Need a blank inode item here just so we don't confuse
+	 * btrfs_get_extent.
+	 */
+	insert_inode_item_key(root);
+	insert_extent(root, sectorsize, sectorsize, sectorsize, 0, sectorsize,
+		      sectorsize, BTRFS_FILE_EXTENT_REG, 0, 1);
+	em = btrfs_get_extent(BTRFS_I(inode), NULL, 0, 2 * sectorsize);
+	if (IS_ERR(em)) {
+		test_err("got an error when we shouldn't have");
+		goto out;
+	}
+	if (em->disk_bytenr != EXTENT_MAP_HOLE) {
+		test_err("expected a hole, got %llu", em->disk_bytenr);
+		goto out;
+	}
+	if (em->start != 0 || em->len != sectorsize) {
+		test_err(
+	"unexpected extent wanted start 0 len %u, got start %llu len %llu",
+			sectorsize, em->start, em->len);
+		goto out;
+	}
+	if (em->flags != vacancy_only) {
+		test_err("wrong flags, wanted %u, have %u", vacancy_only,
+			 em->flags);
+		goto out;
+	}
+	btrfs_free_extent_map(em);
+
+	em = btrfs_get_extent(BTRFS_I(inode), NULL, sectorsize, 2 * sectorsize);
+	if (IS_ERR(em)) {
+		test_err("got an error when we shouldn't have");
+		goto out;
+	}
+	if (btrfs_extent_map_block_start(em) != sectorsize) {
+		test_err("expected a real extent, got %llu",
+			 btrfs_extent_map_block_start(em));
+		goto out;
+	}
+	if (em->start != sectorsize || em->len != sectorsize) {
+		test_err(
+	"unexpected extent wanted start %u len %u, got start %llu len %llu",
+			sectorsize, sectorsize, em->start, em->len);
+		goto out;
+	}
+	if (em->flags != 0) {
+		test_err("unexpected flags set, wanted 0 got %u",
+			 em->flags);
+		goto out;
+	}
+	ret = 0;
+out:
+	if (!IS_ERR(em))
+		btrfs_free_extent_map(em);
+	iput(inode);
+	btrfs_free_dummy_root(root);
+	btrfs_free_dummy_fs_info(fs_info);
+	return ret;
+}
+
+static int test_extent_accounting(u32 sectorsize, u32 nodesize)
+{
+	struct btrfs_fs_info *fs_info = NULL;
+	struct inode *inode = NULL;
+	struct btrfs_root *root = NULL;
+	int ret = -ENOMEM;
+
+	test_msg("running outstanding_extents tests");
+
+	inode = btrfs_new_test_inode();
+	if (!inode) {
+		test_std_err(TEST_ALLOC_INODE);
+		return ret;
+	}
+
+	fs_info = btrfs_alloc_dummy_fs_info(nodesize, sectorsize);
+	if (!fs_info) {
+		test_std_err(TEST_ALLOC_FS_INFO);
+		goto out;
+	}
+
+	root = btrfs_alloc_dummy_root(fs_info);
+	if (IS_ERR(root)) {
+		test_std_err(TEST_ALLOC_ROOT);
+		goto out;
+	}
+
+	BTRFS_I(inode)->root = root;
+
+	/* [BTRFS_MAX_EXTENT_SIZE] */
+	ret = btrfs_set_extent_delalloc(BTRFS_I(inode), 0,
+					BTRFS_MAX_EXTENT_SIZE - 1, 0, NULL);
+	if (ret) {
+		test_err("btrfs_set_extent_delalloc returned %d", ret);
+		goto out;
+	}
+	if (BTRFS_I(inode)->outstanding_extents != 1) {
+		ret = -EINVAL;
+		test_err("miscount, wanted 1, got %u",
+			 BTRFS_I(inode)->outstanding_extents);
+		goto out;
+	}
+
+	/* [BTRFS_MAX_EXTENT_SIZE][sectorsize] */
+	ret = btrfs_set_extent_delalloc(BTRFS_I(inode), BTRFS_MAX_EXTENT_SIZE,
+					BTRFS_MAX_EXTENT_SIZE + sectorsize - 1,
+					0, NULL);
+	if (ret) {
+		test_err("btrfs_set_extent_delalloc returned %d", ret);
+		goto out;
+	}
+	if (BTRFS_I(inode)->outstanding_extents != 2) {
+		ret = -EINVAL;
+		test_err("miscount, wanted 2, got %u",
+			 BTRFS_I(inode)->outstanding_extents);
+		goto out;
+	}
+
+	/* [BTRFS_MAX_EXTENT_SIZE/2][sectorsize HOLE][the rest] */
+	ret = btrfs_clear_extent_bit(&BTRFS_I(inode)->io_tree,
+				     BTRFS_MAX_EXTENT_SIZE >> 1,
+				     (BTRFS_MAX_EXTENT_SIZE >> 1) + sectorsize - 1,
+				     EXTENT_DELALLOC | EXTENT_DELALLOC_NEW, NULL);
+	if (ret) {
+		test_err("clear_extent_bit returned %d", ret);
+		goto out;
+	}
+	if (BTRFS_I(inode)->outstanding_extents != 2) {
+		ret = -EINVAL;
+		test_err("miscount, wanted 2, got %u",
+			 BTRFS_I(inode)->outstanding_extents);
+		goto out;
+	}
+
+	/* [BTRFS_MAX_EXTENT_SIZE][sectorsize] */
+	ret = btrfs_set_extent_delalloc(BTRFS_I(inode), BTRFS_MAX_EXTENT_SIZE >> 1,
+					(BTRFS_MAX_EXTENT_SIZE >> 1)
+					+ sectorsize - 1,
+					0, NULL);
+	if (ret) {
+		test_err("btrfs_set_extent_delalloc returned %d", ret);
+		goto out;
+	}
+	if (BTRFS_I(inode)->outstanding_extents != 2) {
+		ret = -EINVAL;
+		test_err("miscount, wanted 2, got %u",
+			 BTRFS_I(inode)->outstanding_extents);
+		goto out;
+	}
+
+	/*
+	 * [BTRFS_MAX_EXTENT_SIZE+sectorsize][sectorsize HOLE][BTRFS_MAX_EXTENT_SIZE+sectorsize]
+	 */
+	ret = btrfs_set_extent_delalloc(BTRFS_I(inode),
+			BTRFS_MAX_EXTENT_SIZE + 2 * sectorsize,
+			(BTRFS_MAX_EXTENT_SIZE << 1) + 3 * sectorsize - 1,
+			0, NULL);
+	if (ret) {
+		test_err("btrfs_set_extent_delalloc returned %d", ret);
+		goto out;
+	}
+	if (BTRFS_I(inode)->outstanding_extents != 4) {
+		ret = -EINVAL;
+		test_err("miscount, wanted 4, got %u",
+			 BTRFS_I(inode)->outstanding_extents);
+		goto out;
+	}
+
+	/*
+	* [BTRFS_MAX_EXTENT_SIZE+sectorsize][sectorsize][BTRFS_MAX_EXTENT_SIZE+sectorsize]
+	*/
+	ret = btrfs_set_extent_delalloc(BTRFS_I(inode),
+			BTRFS_MAX_EXTENT_SIZE + sectorsize,
+			BTRFS_MAX_EXTENT_SIZE + 2 * sectorsize - 1, 0, NULL);
+	if (ret) {
+		test_err("btrfs_set_extent_delalloc returned %d", ret);
+		goto out;
+	}
+	if (BTRFS_I(inode)->outstanding_extents != 3) {
+		ret = -EINVAL;
+		test_err("miscount, wanted 3, got %u",
+			 BTRFS_I(inode)->outstanding_extents);
+		goto out;
+	}
+
+	/* [BTRFS_MAX_EXTENT_SIZE+4k][4K HOLE][BTRFS_MAX_EXTENT_SIZE+4k] */
+	ret = btrfs_clear_extent_bit(&BTRFS_I(inode)->io_tree,
+				     BTRFS_MAX_EXTENT_SIZE + sectorsize,
+				     BTRFS_MAX_EXTENT_SIZE + 2 * sectorsize - 1,
+				     EXTENT_DELALLOC | EXTENT_DELALLOC_NEW, NULL);
+	if (ret) {
+		test_err("clear_extent_bit returned %d", ret);
+		goto out;
+	}
+	if (BTRFS_I(inode)->outstanding_extents != 4) {
+		ret = -EINVAL;
+		test_err("miscount, wanted 4, got %u",
+			 BTRFS_I(inode)->outstanding_extents);
+		goto out;
+	}
+
+	/*
+	 * Refill the hole again just for good measure, because I thought it
+	 * might fail and I'd rather satisfy my paranoia at this point.
+	 */
+	ret = btrfs_set_extent_delalloc(BTRFS_I(inode),
+			BTRFS_MAX_EXTENT_SIZE + sectorsize,
+			BTRFS_MAX_EXTENT_SIZE + 2 * sectorsize - 1, 0, NULL);
+	if (ret) {
+		test_err("btrfs_set_extent_delalloc returned %d", ret);
+		goto out;
+	}
+	if (BTRFS_I(inode)->outstanding_extents != 3) {
+		ret = -EINVAL;
+		test_err("miscount, wanted 3, got %u",
+			 BTRFS_I(inode)->outstanding_extents);
+		goto out;
+	}
+
+	/* Empty */
+	ret = btrfs_clear_extent_bit(&BTRFS_I(inode)->io_tree, 0, (u64)-1,
+				     EXTENT_DELALLOC | EXTENT_DELALLOC_NEW, NULL);
+	if (ret) {
+		test_err("clear_extent_bit returned %d", ret);
+		goto out;
+	}
+	if (BTRFS_I(inode)->outstanding_extents) {
+		ret = -EINVAL;
+		test_err("miscount, wanted 0, got %u",
+			 BTRFS_I(inode)->outstanding_extents);
+		goto out;
+	}
+	ret = 0;
+out:
+	if (ret)
+		btrfs_clear_extent_bit(&BTRFS_I(inode)->io_tree, 0, (u64)-1,
+				       EXTENT_DELALLOC | EXTENT_DELALLOC_NEW, NULL);
+	iput(inode);
+	btrfs_free_dummy_root(root);
+	btrfs_free_dummy_fs_info(fs_info);
+	return ret;
+}
+
+int btrfs_test_inodes(u32 sectorsize, u32 nodesize)
+{
+	int ret;
+
+	test_msg("running inode tests");
+
+	compressed_only |= EXTENT_FLAG_COMPRESS_ZLIB;
+	prealloc_only |= EXTENT_FLAG_PREALLOC;
+
+	ret = test_btrfs_get_extent(sectorsize, nodesize);
+	if (ret)
+		return ret;
+	ret = test_hole_first(sectorsize, nodesize);
+	if (ret)
+		return ret;
+	return test_extent_accounting(sectorsize, nodesize);
+}