[PATCH 00/11] btrfs: some cleanups and optimizations for extent maps

[PATCH 00/11] btrfs: some cleanups and optimizations for extent maps

[fdmanana]

From: Filipe Manana <fdmanana@suse.com>

These do some cleanups around extent maps and their tests, as well as
some optimizations. These are part of a larger work around extent maps,
but as they are fairly independent and the remainder will take a longer
while, sending these out separately. More details on the change logs.

Filipe Manana (11):
  btrfs: assert extent map is not in a list when setting it up
  btrfs: tests: fix error messages for test case 4 of extent map tests
  btrfs: tests: do not ignore NULL extent maps for extent maps tests
  btrfs: tests: print all values as decimal in messages for extent map tests
  btrfs: unexport add_extent_mapping()
  btrfs: remove redundant value assignment at btrfs_add_extent_mapping()
  btrfs: log messages at unpin_extent_range() during unexpected cases
  btrfs: avoid useless rbtree iterations when attempting to merge extent map
  btrfs: make extent_map_end() argument const
  btrfs: refactor mergable_maps() for more readability
  btrfs: use the flags of an extent map to identify the compression type

 fs/btrfs/compression.c            |   4 +-
 fs/btrfs/defrag.c                 |   8 +-
 fs/btrfs/extent_io.c              |  13 ++-
 fs/btrfs/extent_map.c             | 139 ++++++++++++++++--------------
 fs/btrfs/extent_map.h             |  64 +++++++++++---
 fs/btrfs/file-item.c              |   9 +-
 fs/btrfs/file.c                   |  10 +--
 fs/btrfs/inode.c                  |  35 ++++----
 fs/btrfs/relocation.c             |   2 +-
 fs/btrfs/tests/extent-map-tests.c | 103 +++++++++++++---------
 fs/btrfs/tests/inode-tests.c      |  60 ++++++-------
 fs/btrfs/tree-log.c               |  16 ++--
 include/trace/events/btrfs.h      |  21 +++--
 13 files changed, 272 insertions(+), 212 deletions(-)

-- 
2.40.1

[PATCH 01/11] btrfs: assert extent map is not in a list when setting it up

[fdmanana]

From: Filipe Manana <fdmanana@suse.com>

When setting up a new extent map, at setup_extent_mapping(), we're doing
a list move operation to add the extent map the tree's list of modified
extents. This is confusing because at this point the extent map can not
be in any list, because it's a new extent map. So replace the list move
with a list add and add an assertion that checks that the extent map is
not currently in any list.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
---
 fs/btrfs/extent_map.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/fs/btrfs/extent_map.c b/fs/btrfs/extent_map.c
index 80f86503a5cd..d29097a8550a 100644
--- a/fs/btrfs/extent_map.c
+++ b/fs/btrfs/extent_map.c
@@ -345,8 +345,10 @@ static inline void setup_extent_mapping(struct extent_map_tree *tree,
 	em->mod_start = em->start;
 	em->mod_len = em->len;
 
+	ASSERT(list_empty(&em->list));
+
 	if (modified)
-		list_move(&em->list, &tree->modified_extents);
+		list_add(&em->list, &tree->modified_extents);
 	else
 		try_merge_map(tree, em);
 }
-- 
2.40.1

[PATCH 02/11] btrfs: tests: fix error messages for test case 4 of extent map tests

[fdmanana]

From: Filipe Manana <fdmanana@suse.com>

In test case 4 for extent maps, if we error out we are supposed to print
in interval but instead of printing a non-inclusive end offset, we are
printing the length of the interval, which makes it confusing. So fix
that to print the exclusive end offset instead.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
---
 fs/btrfs/tests/extent-map-tests.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/fs/btrfs/tests/extent-map-tests.c b/fs/btrfs/tests/extent-map-tests.c
index 8602f94cc29d..ac64eafad703 100644
--- a/fs/btrfs/tests/extent-map-tests.c
+++ b/fs/btrfs/tests/extent-map-tests.c
@@ -388,13 +388,13 @@ static int __test_case_4(struct btrfs_fs_info *fs_info,
 	write_unlock(&em_tree->lock);
 	if (ret) {
 		test_err("case4 [0x%llx 0x%llx): ret %d",
-			 start, len, ret);
+			 start, start + len, ret);
 		goto out;
 	}
 	if (em && (start < em->start || start + len > extent_map_end(em))) {
 		test_err(
 "case4 [0x%llx 0x%llx): ret %d, added wrong em (start 0x%llx len 0x%llx block_start 0x%llx block_len 0x%llx)",
-			 start, len, ret, em->start, em->len, em->block_start,
+			 start, start + len, ret, em->start, em->len, em->block_start,
 			 em->block_len);
 		ret = -EINVAL;
 	}
-- 
2.40.1

[PATCH 03/11] btrfs: tests: do not ignore NULL extent maps for extent maps tests

[fdmanana]

From: Filipe Manana <fdmanana@suse.com>

Several of the extent map tests call btrfs_add_extent_mapping() which is
supposed to succeed and return an extent map through the pointer to
pointer argument. However the tests are deliberately ignoring a NULL
extent map, which is not expected to happen. So change the tests to error
out if a NULL extent map is found.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
---
 fs/btrfs/tests/extent-map-tests.c | 40 +++++++++++++++++++++++--------
 1 file changed, 30 insertions(+), 10 deletions(-)

diff --git a/fs/btrfs/tests/extent-map-tests.c b/fs/btrfs/tests/extent-map-tests.c
index ac64eafad703..024588d02551 100644
--- a/fs/btrfs/tests/extent-map-tests.c
+++ b/fs/btrfs/tests/extent-map-tests.c
@@ -121,9 +121,14 @@ static int test_case_1(struct btrfs_fs_info *fs_info,
 		test_err("case1 [%llu %llu]: ret %d", start, start + len, ret);
 		goto out;
 	}
-	if (em &&
-	    (em->start != 0 || extent_map_end(em) != SZ_16K ||
-	     em->block_start != 0 || em->block_len != SZ_16K)) {
+	if (!em) {
+		test_err("case1 [%llu %llu]: no extent map returned",
+			 start, start + len);
+		ret = -ENOENT;
+		goto out;
+	}
+	if (em->start != 0 || extent_map_end(em) != SZ_16K ||
+	    em->block_start != 0 || em->block_len != SZ_16K) {
 		test_err(
 "case1 [%llu %llu]: ret %d return a wrong em (start %llu len %llu block_start %llu block_len %llu",
 			 start, start + len, ret, em->start, em->len,
@@ -209,9 +214,13 @@ static int test_case_2(struct btrfs_fs_info *fs_info,
 		test_err("case2 [0 1K]: ret %d", ret);
 		goto out;
 	}
-	if (em &&
-	    (em->start != 0 || extent_map_end(em) != SZ_1K ||
-	     em->block_start != EXTENT_MAP_INLINE || em->block_len != (u64)-1)) {
+	if (!em) {
+		test_err("case2 [0 1K]: no extent map returned");
+		ret = -ENOENT;
+		goto out;
+	}
+	if (em->start != 0 || extent_map_end(em) != SZ_1K ||
+	    em->block_start != EXTENT_MAP_INLINE || em->block_len != (u64)-1) {
 		test_err(
 "case2 [0 1K]: ret %d return a wrong em (start %llu len %llu block_start %llu block_len %llu",
 			 ret, em->start, em->len, em->block_start,
@@ -272,13 +281,18 @@ static int __test_case_3(struct btrfs_fs_info *fs_info,
 			 start, start + len, ret);
 		goto out;
 	}
+	if (!em) {
+		test_err("case3 [0x%llx 0x%llx): no extent map returned",
+			 start, start + len);
+		ret = -ENOENT;
+		goto out;
+	}
 	/*
 	 * Since bytes within em are contiguous, em->block_start is identical to
 	 * em->start.
 	 */
-	if (em &&
-	    (start < em->start || start + len > extent_map_end(em) ||
-	     em->start != em->block_start || em->len != em->block_len)) {
+	if (start < em->start || start + len > extent_map_end(em) ||
+	    em->start != em->block_start || em->len != em->block_len) {
 		test_err(
 "case3 [0x%llx 0x%llx): ret %d em (start 0x%llx len 0x%llx block_start 0x%llx block_len 0x%llx)",
 			 start, start + len, ret, em->start, em->len,
@@ -391,7 +405,13 @@ static int __test_case_4(struct btrfs_fs_info *fs_info,
 			 start, start + len, ret);
 		goto out;
 	}
-	if (em && (start < em->start || start + len > extent_map_end(em))) {
+	if (!em) {
+		test_err("case4 [0x%llx 0x%llx): no extent map returned",
+			 start, start + len);
+		ret = -ENOENT;
+		goto out;
+	}
+	if (start < em->start || start + len > extent_map_end(em)) {
 		test_err(
 "case4 [0x%llx 0x%llx): ret %d, added wrong em (start 0x%llx len 0x%llx block_start 0x%llx block_len 0x%llx)",
 			 start, start + len, ret, em->start, em->len, em->block_start,
-- 
2.40.1

[PATCH 04/11] btrfs: tests: print all values as decimal in messages for extent map tests

[fdmanana]

From: Filipe Manana <fdmanana@suse.com>

Some error messages of the extent map tests print decimal values of start
offsets and lengths, while other are oddly printing in hexadecimal, which
is far less human friendly, specially taking into consideration that all
the values are small and multiples of 4K, so it's a lot easier to read
them as decimal values. Change the format specifiers to print as decimal
instead.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
---
 fs/btrfs/tests/extent-map-tests.c | 14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/fs/btrfs/tests/extent-map-tests.c b/fs/btrfs/tests/extent-map-tests.c
index 024588d02551..1eb442ea89a5 100644
--- a/fs/btrfs/tests/extent-map-tests.c
+++ b/fs/btrfs/tests/extent-map-tests.c
@@ -25,7 +25,7 @@ static void free_extent_map_tree(struct extent_map_tree *em_tree)
 #ifdef CONFIG_BTRFS_DEBUG
 		if (refcount_read(&em->refs) != 1) {
 			test_err(
-"em leak: em (start 0x%llx len 0x%llx block_start 0x%llx block_len 0x%llx) refs %d",
+"em leak: em (start %llu len %llu block_start %llu block_len %llu) refs %d",
 				 em->start, em->len, em->block_start,
 				 em->block_len, refcount_read(&em->refs));
 
@@ -277,12 +277,12 @@ static int __test_case_3(struct btrfs_fs_info *fs_info,
 	ret = btrfs_add_extent_mapping(fs_info, em_tree, &em, start, len);
 	write_unlock(&em_tree->lock);
 	if (ret) {
-		test_err("case3 [0x%llx 0x%llx): ret %d",
+		test_err("case3 [%llu %llu): ret %d",
 			 start, start + len, ret);
 		goto out;
 	}
 	if (!em) {
-		test_err("case3 [0x%llx 0x%llx): no extent map returned",
+		test_err("case3 [%llu %llu): no extent map returned",
 			 start, start + len);
 		ret = -ENOENT;
 		goto out;
@@ -294,7 +294,7 @@ static int __test_case_3(struct btrfs_fs_info *fs_info,
 	if (start < em->start || start + len > extent_map_end(em) ||
 	    em->start != em->block_start || em->len != em->block_len) {
 		test_err(
-"case3 [0x%llx 0x%llx): ret %d em (start 0x%llx len 0x%llx block_start 0x%llx block_len 0x%llx)",
+"case3 [%llu %llu): ret %d em (start %llu len %llu block_start %llu block_len %llu)",
 			 start, start + len, ret, em->start, em->len,
 			 em->block_start, em->block_len);
 		ret = -EINVAL;
@@ -401,19 +401,19 @@ static int __test_case_4(struct btrfs_fs_info *fs_info,
 	ret = btrfs_add_extent_mapping(fs_info, em_tree, &em, start, len);
 	write_unlock(&em_tree->lock);
 	if (ret) {
-		test_err("case4 [0x%llx 0x%llx): ret %d",
+		test_err("case4 [%llu %llu): ret %d",
 			 start, start + len, ret);
 		goto out;
 	}
 	if (!em) {
-		test_err("case4 [0x%llx 0x%llx): no extent map returned",
+		test_err("case4 [%llu %llu): no extent map returned",
 			 start, start + len);
 		ret = -ENOENT;
 		goto out;
 	}
 	if (start < em->start || start + len > extent_map_end(em)) {
 		test_err(
-"case4 [0x%llx 0x%llx): ret %d, added wrong em (start 0x%llx len 0x%llx block_start 0x%llx block_len 0x%llx)",
+"case4 [%llu %llu): ret %d, added wrong em (start %llu len %llu block_start %llu block_len %llu)",
 			 start, start + len, ret, em->start, em->len, em->block_start,
 			 em->block_len);
 		ret = -EINVAL;
-- 
2.40.1

[PATCH 05/11] btrfs: unexport add_extent_mapping()

[fdmanana]

From: Filipe Manana <fdmanana@suse.com>

There's no need to export add_extent_mapping(), as it's only used inside
extent_map.c and in the self tests. For the tests we can use instead
btrfs_add_extent_mapping(), which will accomplish exactly the same as we
don't expect collisions in any of them. So unexport it and make the tests
use btrfs_add_extent_mapping() instead of add_extent_mapping().

Signed-off-by: Filipe Manana <fdmanana@suse.com>
---
 fs/btrfs/extent_map.c             |  4 +--
 fs/btrfs/extent_map.h             |  2 --
 fs/btrfs/tests/extent-map-tests.c | 45 ++++++++++++++++---------------
 3 files changed, 25 insertions(+), 26 deletions(-)

diff --git a/fs/btrfs/extent_map.c b/fs/btrfs/extent_map.c
index d29097a8550a..18a5c4332ed6 100644
--- a/fs/btrfs/extent_map.c
+++ b/fs/btrfs/extent_map.c
@@ -366,8 +366,8 @@ static inline void setup_extent_mapping(struct extent_map_tree *tree,
  * into the tree directly, with an additional reference taken, or a
  * reference dropped if the merge attempt was successful.
  */
-int add_extent_mapping(struct extent_map_tree *tree,
-		       struct extent_map *em, int modified)
+static int add_extent_mapping(struct extent_map_tree *tree,
+			      struct extent_map *em, int modified)
 {
 	int ret = 0;
 
diff --git a/fs/btrfs/extent_map.h b/fs/btrfs/extent_map.h
index 66f8dd26487b..5663137471fe 100644
--- a/fs/btrfs/extent_map.h
+++ b/fs/btrfs/extent_map.h
@@ -74,8 +74,6 @@ static inline u64 extent_map_end(struct extent_map *em)
 void extent_map_tree_init(struct extent_map_tree *tree);
 struct extent_map *lookup_extent_mapping(struct extent_map_tree *tree,
 					 u64 start, u64 len);
-int add_extent_mapping(struct extent_map_tree *tree,
-		       struct extent_map *em, int modified);
 void remove_extent_mapping(struct extent_map_tree *tree, struct extent_map *em);
 int split_extent_map(struct btrfs_inode *inode, u64 start, u64 len, u64 pre,
 		     u64 new_logical);
diff --git a/fs/btrfs/tests/extent-map-tests.c b/fs/btrfs/tests/extent-map-tests.c
index 1eb442ea89a5..59bbf714225c 100644
--- a/fs/btrfs/tests/extent-map-tests.c
+++ b/fs/btrfs/tests/extent-map-tests.c
@@ -73,7 +73,7 @@ static int test_case_1(struct btrfs_fs_info *fs_info,
 	em->block_start = 0;
 	em->block_len = SZ_16K;
 	write_lock(&em_tree->lock);
-	ret = add_extent_mapping(em_tree, em, 0);
+	ret = btrfs_add_extent_mapping(fs_info, em_tree, &em, em->start, em->len);
 	write_unlock(&em_tree->lock);
 	if (ret < 0) {
 		test_err("cannot add extent range [0, 16K)");
@@ -94,7 +94,7 @@ static int test_case_1(struct btrfs_fs_info *fs_info,
 	em->block_start = SZ_32K; /* avoid merging */
 	em->block_len = SZ_4K;
 	write_lock(&em_tree->lock);
-	ret = add_extent_mapping(em_tree, em, 0);
+	ret = btrfs_add_extent_mapping(fs_info, em_tree, &em, em->start, em->len);
 	write_unlock(&em_tree->lock);
 	if (ret < 0) {
 		test_err("cannot add extent range [16K, 20K)");
@@ -166,7 +166,7 @@ static int test_case_2(struct btrfs_fs_info *fs_info,
 	em->block_start = EXTENT_MAP_INLINE;
 	em->block_len = (u64)-1;
 	write_lock(&em_tree->lock);
-	ret = add_extent_mapping(em_tree, em, 0);
+	ret = btrfs_add_extent_mapping(fs_info, em_tree, &em, em->start, em->len);
 	write_unlock(&em_tree->lock);
 	if (ret < 0) {
 		test_err("cannot add extent range [0, 1K)");
@@ -187,7 +187,7 @@ static int test_case_2(struct btrfs_fs_info *fs_info,
 	em->block_start = SZ_4K;
 	em->block_len = SZ_4K;
 	write_lock(&em_tree->lock);
-	ret = add_extent_mapping(em_tree, em, 0);
+	ret = btrfs_add_extent_mapping(fs_info, em_tree, &em, em->start, em->len);
 	write_unlock(&em_tree->lock);
 	if (ret < 0) {
 		test_err("cannot add extent range [4K, 8K)");
@@ -253,7 +253,7 @@ static int __test_case_3(struct btrfs_fs_info *fs_info,
 	em->block_start = SZ_4K;
 	em->block_len = SZ_4K;
 	write_lock(&em_tree->lock);
-	ret = add_extent_mapping(em_tree, em, 0);
+	ret = btrfs_add_extent_mapping(fs_info, em_tree, &em, em->start, em->len);
 	write_unlock(&em_tree->lock);
 	if (ret < 0) {
 		test_err("cannot add extent range [4K, 8K)");
@@ -357,7 +357,7 @@ static int __test_case_4(struct btrfs_fs_info *fs_info,
 	em->block_start = 0;
 	em->block_len = SZ_8K;
 	write_lock(&em_tree->lock);
-	ret = add_extent_mapping(em_tree, em, 0);
+	ret = btrfs_add_extent_mapping(fs_info, em_tree, &em, em->start, em->len);
 	write_unlock(&em_tree->lock);
 	if (ret < 0) {
 		test_err("cannot add extent range [0, 8K)");
@@ -378,7 +378,7 @@ static int __test_case_4(struct btrfs_fs_info *fs_info,
 	em->block_start = SZ_16K; /* avoid merging */
 	em->block_len = 24 * SZ_1K;
 	write_lock(&em_tree->lock);
-	ret = add_extent_mapping(em_tree, em, 0);
+	ret = btrfs_add_extent_mapping(fs_info, em_tree, &em, em->start, em->len);
 	write_unlock(&em_tree->lock);
 	if (ret < 0) {
 		test_err("cannot add extent range [8K, 32K)");
@@ -463,7 +463,8 @@ static int test_case_4(struct btrfs_fs_info *fs_info,
 	return ret;
 }
 
-static int add_compressed_extent(struct extent_map_tree *em_tree,
+static int add_compressed_extent(struct btrfs_fs_info *fs_info,
+				 struct extent_map_tree *em_tree,
 				 u64 start, u64 len, u64 block_start)
 {
 	struct extent_map *em;
@@ -481,7 +482,7 @@ static int add_compressed_extent(struct extent_map_tree *em_tree,
 	em->block_len = SZ_4K;
 	set_bit(EXTENT_FLAG_COMPRESSED, &em->flags);
 	write_lock(&em_tree->lock);
-	ret = add_extent_mapping(em_tree, em, 0);
+	ret = btrfs_add_extent_mapping(fs_info, em_tree, &em, em->start, em->len);
 	write_unlock(&em_tree->lock);
 	free_extent_map(em);
 	if (ret < 0) {
@@ -587,7 +588,7 @@ static int validate_range(struct extent_map_tree *em_tree, int index)
  * They'll have the EXTENT_FLAG_COMPRESSED flag set to keep the em tree from
  * merging the em's.
  */
-static int test_case_5(void)
+static int test_case_5(struct btrfs_fs_info *fs_info)
 {
 	struct extent_map_tree *em_tree;
 	struct inode *inode;
@@ -605,35 +606,35 @@ static int test_case_5(void)
 	em_tree = &BTRFS_I(inode)->extent_tree;
 
 	/* [0, 12k) */
-	ret = add_compressed_extent(em_tree, 0, SZ_4K * 3, 0);
+	ret = add_compressed_extent(fs_info, em_tree, 0, SZ_4K * 3, 0);
 	if (ret) {
 		test_err("cannot add extent range [0, 12K)");
 		goto out;
 	}
 
 	/* [12k, 24k) */
-	ret = add_compressed_extent(em_tree, SZ_4K * 3, SZ_4K * 3, SZ_4K);
+	ret = add_compressed_extent(fs_info, em_tree, SZ_4K * 3, SZ_4K * 3, SZ_4K);
 	if (ret) {
 		test_err("cannot add extent range [12k, 24k)");
 		goto out;
 	}
 
 	/* [24k, 36k) */
-	ret = add_compressed_extent(em_tree, SZ_4K * 6, SZ_4K * 3, SZ_8K);
+	ret = add_compressed_extent(fs_info, em_tree, SZ_4K * 6, SZ_4K * 3, SZ_8K);
 	if (ret) {
 		test_err("cannot add extent range [12k, 24k)");
 		goto out;
 	}
 
 	/* [36k, 40k) */
-	ret = add_compressed_extent(em_tree, SZ_32K + SZ_4K, SZ_4K, SZ_4K * 3);
+	ret = add_compressed_extent(fs_info, em_tree, SZ_32K + SZ_4K, SZ_4K, SZ_4K * 3);
 	if (ret) {
 		test_err("cannot add extent range [12k, 24k)");
 		goto out;
 	}
 
 	/* [40k, 64k) */
-	ret = add_compressed_extent(em_tree, SZ_4K * 10, SZ_4K * 6, SZ_16K);
+	ret = add_compressed_extent(fs_info, em_tree, SZ_4K * 10, SZ_4K * 6, SZ_16K);
 	if (ret) {
 		test_err("cannot add extent range [12k, 24k)");
 		goto out;
@@ -685,11 +686,11 @@ static int test_case_6(struct btrfs_fs_info *fs_info, struct extent_map_tree *em
 	struct extent_map *em = NULL;
 	int ret;
 
-	ret = add_compressed_extent(em_tree, 0, SZ_4K, 0);
+	ret = add_compressed_extent(fs_info, em_tree, 0, SZ_4K, 0);
 	if (ret)
 		goto out;
 
-	ret = add_compressed_extent(em_tree, SZ_4K, SZ_4K, 0);
+	ret = add_compressed_extent(fs_info, em_tree, SZ_4K, SZ_4K, 0);
 	if (ret)
 		goto out;
 
@@ -733,7 +734,7 @@ static int test_case_6(struct btrfs_fs_info *fs_info, struct extent_map_tree *em
  * true would mess up the start/end calculations and subsequent splits would be
  * incorrect.
  */
-static int test_case_7(void)
+static int test_case_7(struct btrfs_fs_info *fs_info)
 {
 	struct extent_map_tree *em_tree;
 	struct extent_map *em;
@@ -764,7 +765,7 @@ static int test_case_7(void)
 	em->block_len = SZ_4K;
 	set_bit(EXTENT_FLAG_PINNED, &em->flags);
 	write_lock(&em_tree->lock);
-	ret = add_extent_mapping(em_tree, em, 0);
+	ret = btrfs_add_extent_mapping(fs_info, em_tree, &em, em->start, em->len);
 	write_unlock(&em_tree->lock);
 	if (ret < 0) {
 		test_err("couldn't add extent map");
@@ -785,7 +786,7 @@ static int test_case_7(void)
 	em->block_start = SZ_32K;
 	em->block_len = SZ_16K;
 	write_lock(&em_tree->lock);
-	ret = add_extent_mapping(em_tree, em, 0);
+	ret = btrfs_add_extent_mapping(fs_info, em_tree, &em, em->start, em->len);
 	write_unlock(&em_tree->lock);
 	if (ret < 0) {
 		test_err("couldn't add extent map");
@@ -1022,13 +1023,13 @@ int btrfs_test_extent_map(void)
 	ret = test_case_4(fs_info, em_tree);
 	if (ret)
 		goto out;
-	ret = test_case_5();
+	ret = test_case_5(fs_info);
 	if (ret)
 		goto out;
 	ret = test_case_6(fs_info, em_tree);
 	if (ret)
 		goto out;
-	ret = test_case_7();
+	ret = test_case_7(fs_info);
 	if (ret)
 		goto out;
 
-- 
2.40.1

[PATCH 06/11] btrfs: remove redundant value assignment at btrfs_add_extent_mapping()

[fdmanana]

From: Filipe Manana <fdmanana@suse.com>

At btrfs_add_extent_mapping(), in case add_extent_mapping() returned
-EEXIST, it's pointless to assign 0 to 'ret' since we will assign a value
to it shortly after, without 'ret' being used before that. So remove that
pointless assignment.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
---
 fs/btrfs/extent_map.c | 2 --
 1 file changed, 2 deletions(-)

diff --git a/fs/btrfs/extent_map.c b/fs/btrfs/extent_map.c
index 18a5c4332ed6..a3d69c943eec 100644
--- a/fs/btrfs/extent_map.c
+++ b/fs/btrfs/extent_map.c
@@ -586,8 +586,6 @@ int btrfs_add_extent_mapping(struct btrfs_fs_info *fs_info,
 	if (ret == -EEXIST) {
 		struct extent_map *existing;
 
-		ret = 0;
-
 		existing = search_extent_mapping(em_tree, start, len);
 
 		trace_btrfs_handle_em_exist(fs_info, existing, em, start, len);
-- 
2.40.1

[PATCH 07/11] btrfs: log messages at unpin_extent_range() during unexpected cases

[fdmanana]

From: Filipe Manana <fdmanana@suse.com>

At unpin_extent_range() we trigger a WARN_ON() when we don't find an
extent map or we find one with a start offset not matching the start
offset of the target range. This however isn't very useful for debugging
because:

1) We don't know which condition was triggered, as they are both in the
   same WARN_ON() call;

2) We don't know which inode was affected, from which root, for which
   range, what's the start offset of the extent map, and so on.

So trigger a separate warning for each case and log a message for each
case providing information about the inode, its root, the target range,
the generation and the start offset of the extent map we found.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
---
 fs/btrfs/extent_map.c | 22 ++++++++++++++++------
 fs/btrfs/extent_map.h |  2 +-
 fs/btrfs/inode.c      |  2 +-
 3 files changed, 18 insertions(+), 8 deletions(-)

diff --git a/fs/btrfs/extent_map.c b/fs/btrfs/extent_map.c
index a3d69c943eec..48230a1179b0 100644
--- a/fs/btrfs/extent_map.c
+++ b/fs/btrfs/extent_map.c
@@ -280,7 +280,7 @@ static void try_merge_map(struct extent_map_tree *tree, struct extent_map *em)
 /*
  * Unpin an extent from the cache.
  *
- * @tree:	tree to unpin the extent in
+ * @inode:	the inode from which we are unpinning an extent range
  * @start:	logical offset in the file
  * @len:	length of the extent
  * @gen:	generation that this extent has been modified in
@@ -289,9 +289,10 @@ static void try_merge_map(struct extent_map_tree *tree, struct extent_map *em)
  * to the generation that actually added the file item to the inode so we know
  * we need to sync this extent when we call fsync().
  */
-int unpin_extent_cache(struct extent_map_tree *tree, u64 start, u64 len,
-		       u64 gen)
+int unpin_extent_cache(struct btrfs_inode *inode, u64 start, u64 len, u64 gen)
 {
+	struct btrfs_fs_info *fs_info = inode->root->fs_info;
+	struct extent_map_tree *tree = &inode->extent_tree;
 	int ret = 0;
 	struct extent_map *em;
 	bool prealloc = false;
@@ -299,10 +300,19 @@ int unpin_extent_cache(struct extent_map_tree *tree, u64 start, u64 len,
 	write_lock(&tree->lock);
 	em = lookup_extent_mapping(tree, start, len);
 
-	WARN_ON(!em || em->start != start);
-
-	if (!em)
+	if (WARN_ON(!em)) {
+		btrfs_warn(fs_info,
+"no extent map found for inode %llu (root %lld) when unpinning extent range [%llu, %llu), generation %llu",
+			   btrfs_ino(inode), btrfs_root_id(inode->root),
+			   start, len, gen);
 		goto out;
+	}
+
+	if (WARN_ON(em->start != start))
+		btrfs_warn(fs_info,
+"found extent map for inode %llu (root %lld) with unexpected start offset %llu when unpinning extent range [%llu, %llu), generation %llu",
+			   btrfs_ino(inode), btrfs_root_id(inode->root),
+			   em->start, start, len, gen);
 
 	em->generation = gen;
 	clear_bit(EXTENT_FLAG_PINNED, &em->flags);
diff --git a/fs/btrfs/extent_map.h b/fs/btrfs/extent_map.h
index 5663137471fe..cd1a9115908d 100644
--- a/fs/btrfs/extent_map.h
+++ b/fs/btrfs/extent_map.h
@@ -82,7 +82,7 @@ struct extent_map *alloc_extent_map(void);
 void free_extent_map(struct extent_map *em);
 int __init extent_map_init(void);
 void __cold extent_map_exit(void);
-int unpin_extent_cache(struct extent_map_tree *tree, u64 start, u64 len, u64 gen);
+int unpin_extent_cache(struct btrfs_inode *inode, u64 start, u64 len, u64 gen);
 void clear_em_logging(struct extent_map_tree *tree, struct extent_map *em);
 struct extent_map *search_extent_mapping(struct extent_map_tree *tree,
 					 u64 start, u64 len);
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index f8647d8271b7..f7f48c2f0276 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -3127,7 +3127,7 @@ int btrfs_finish_one_ordered(struct btrfs_ordered_extent *ordered_extent)
 						ordered_extent->disk_num_bytes);
 		}
 	}
-	unpin_extent_cache(&inode->extent_tree, ordered_extent->file_offset,
+	unpin_extent_cache(inode, ordered_extent->file_offset,
 			   ordered_extent->num_bytes, trans->transid);
 	if (ret < 0) {
 		btrfs_abort_transaction(trans, ret);
-- 
2.40.1

[PATCH 08/11] btrfs: avoid useless rbtree iterations when attempting to merge extent map

[fdmanana]

From: Filipe Manana <fdmanana@suse.com>

When trying to merge an extent map that was just inserted or unpinned, we
will try to merge it with any adjacent extent map that is suitable.

However we will only check if our extent map is mergeable after searching
for the previous and next extent maps in the rbtree, meaning that we are
doing unnecessary calls to rb_prev() and rb_next() in case our extent map
is not mergeable (it's compressed, in the list of modifed extents, being
logged or pinned), wasting CPU time chasing rbtree pointers and pulling
in unnecessary cache lines.

So change the logic to check first if an extent map is mergeable before
searching for the next and previous extent maps in the rbtree.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
---
 fs/btrfs/extent_map.c | 38 +++++++++++++++++++++-----------------
 1 file changed, 21 insertions(+), 17 deletions(-)

diff --git a/fs/btrfs/extent_map.c b/fs/btrfs/extent_map.c
index 48230a1179b0..72df548a4c86 100644
--- a/fs/btrfs/extent_map.c
+++ b/fs/btrfs/extent_map.c
@@ -187,31 +187,32 @@ static inline u64 extent_map_block_end(const struct extent_map *em)
 	return em->block_start + em->block_len;
 }
 
-/* Check to see if two extent_map structs are adjacent and safe to merge. */
-static int mergable_maps(struct extent_map *prev, struct extent_map *next)
+static bool can_merge_extent_map(const struct extent_map *em)
 {
-	if (test_bit(EXTENT_FLAG_PINNED, &prev->flags))
-		return 0;
+	if (test_bit(EXTENT_FLAG_PINNED, &em->flags))
+		return false;
 
-	/*
-	 * don't merge compressed extents, we need to know their
-	 * actual size
-	 */
-	if (test_bit(EXTENT_FLAG_COMPRESSED, &prev->flags))
-		return 0;
+	/* Don't merge compressed extents, we need to know their actual size. */
+	if (test_bit(EXTENT_FLAG_COMPRESSED, &em->flags))
+		return false;
 
-	if (test_bit(EXTENT_FLAG_LOGGING, &prev->flags) ||
-	    test_bit(EXTENT_FLAG_LOGGING, &next->flags))
-		return 0;
+	if (test_bit(EXTENT_FLAG_LOGGING, &em->flags))
+		return false;
 
 	/*
 	 * We don't want to merge stuff that hasn't been written to the log yet
 	 * since it may not reflect exactly what is on disk, and that would be
 	 * bad.
 	 */
-	if (!list_empty(&prev->list) || !list_empty(&next->list))
-		return 0;
+	if (!list_empty(&em->list))
+		return false;
+
+	return true;
+}
 
+/* Check to see if two extent_map structs are adjacent and safe to merge. */
+static int mergable_maps(struct extent_map *prev, struct extent_map *next)
+{
 	if (extent_map_end(prev) == next->start &&
 	    prev->flags == next->flags &&
 	    ((next->block_start == EXTENT_MAP_HOLE &&
@@ -241,11 +242,14 @@ static void try_merge_map(struct extent_map_tree *tree, struct extent_map *em)
 	if (refcount_read(&em->refs) > 2)
 		return;
 
+	if (!can_merge_extent_map(em))
+		return;
+
 	if (em->start != 0) {
 		rb = rb_prev(&em->rb_node);
 		if (rb)
 			merge = rb_entry(rb, struct extent_map, rb_node);
-		if (rb && mergable_maps(merge, em)) {
+		if (rb && can_merge_extent_map(merge) && mergable_maps(merge, em)) {
 			em->start = merge->start;
 			em->orig_start = merge->orig_start;
 			em->len += merge->len;
@@ -265,7 +269,7 @@ static void try_merge_map(struct extent_map_tree *tree, struct extent_map *em)
 	rb = rb_next(&em->rb_node);
 	if (rb)
 		merge = rb_entry(rb, struct extent_map, rb_node);
-	if (rb && mergable_maps(em, merge)) {
+	if (rb && can_merge_extent_map(merge) && mergable_maps(em, merge)) {
 		em->len += merge->len;
 		em->block_len += merge->block_len;
 		rb_erase_cached(&merge->rb_node, &tree->map);
-- 
2.40.1

[PATCH 09/11] btrfs: make extent_map_end() argument const

[fdmanana]

From: Filipe Manana <fdmanana@suse.com>

The extent map pointer argument for extent_map_end() can be const as we
are not modifyng anything in the extent map. So make it const, as it will
allow further changes to callers that have a const extent map pointer.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
---
 fs/btrfs/extent_map.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/btrfs/extent_map.h b/fs/btrfs/extent_map.h
index cd1a9115908d..44dc0cb310ea 100644
--- a/fs/btrfs/extent_map.h
+++ b/fs/btrfs/extent_map.h
@@ -64,7 +64,7 @@ static inline int extent_map_in_tree(const struct extent_map *em)
 	return !RB_EMPTY_NODE(&em->rb_node);
 }
 
-static inline u64 extent_map_end(struct extent_map *em)
+static inline u64 extent_map_end(const struct extent_map *em)
 {
 	if (em->start + em->len < em->start)
 		return (u64)-1;
-- 
2.40.1

[PATCH 10/11] btrfs: refactor mergable_maps() for more readability

[fdmanana]

From: Filipe Manana <fdmanana@suse.com>

At mergable_maps() Instead of having a single if statement with many
ORed and ANDed conditions, refacator it with mulple if statements that
check a single condition and return immediately once a requirement fails.
This makes it easier to read.

Also change the return type from int to bool, make the arguments const
and rename the function from mergable_maps() to mergeable_maps().

Signed-off-by: Filipe Manana <fdmanana@suse.com>
---
 fs/btrfs/extent_map.c | 28 ++++++++++++++--------------
 1 file changed, 14 insertions(+), 14 deletions(-)

diff --git a/fs/btrfs/extent_map.c b/fs/btrfs/extent_map.c
index 72df548a4c86..650ab88ad7dc 100644
--- a/fs/btrfs/extent_map.c
+++ b/fs/btrfs/extent_map.c
@@ -211,19 +211,19 @@ static bool can_merge_extent_map(const struct extent_map *em)
 }
 
 /* Check to see if two extent_map structs are adjacent and safe to merge. */
-static int mergable_maps(struct extent_map *prev, struct extent_map *next)
+static bool mergeable_maps(const struct extent_map *prev, const struct extent_map *next)
 {
-	if (extent_map_end(prev) == next->start &&
-	    prev->flags == next->flags &&
-	    ((next->block_start == EXTENT_MAP_HOLE &&
-	      prev->block_start == EXTENT_MAP_HOLE) ||
-	     (next->block_start == EXTENT_MAP_INLINE &&
-	      prev->block_start == EXTENT_MAP_INLINE) ||
-	     (next->block_start < EXTENT_MAP_LAST_BYTE - 1 &&
-	      next->block_start == extent_map_block_end(prev)))) {
-		return 1;
-	}
-	return 0;
+	if (extent_map_end(prev) != next->start)
+		return false;
+
+	if (prev->flags != next->flags)
+		return false;
+
+	if (next->block_start < EXTENT_MAP_LAST_BYTE - 1)
+		return next->block_start == extent_map_block_end(prev);
+
+	/* HOLES and INLINE extents */
+	return next->block_start == prev->block_start;
 }
 
 static void try_merge_map(struct extent_map_tree *tree, struct extent_map *em)
@@ -249,7 +249,7 @@ static void try_merge_map(struct extent_map_tree *tree, struct extent_map *em)
 		rb = rb_prev(&em->rb_node);
 		if (rb)
 			merge = rb_entry(rb, struct extent_map, rb_node);
-		if (rb && can_merge_extent_map(merge) && mergable_maps(merge, em)) {
+		if (rb && can_merge_extent_map(merge) && mergeable_maps(merge, em)) {
 			em->start = merge->start;
 			em->orig_start = merge->orig_start;
 			em->len += merge->len;
@@ -269,7 +269,7 @@ static void try_merge_map(struct extent_map_tree *tree, struct extent_map *em)
 	rb = rb_next(&em->rb_node);
 	if (rb)
 		merge = rb_entry(rb, struct extent_map, rb_node);
-	if (rb && can_merge_extent_map(merge) && mergable_maps(em, merge)) {
+	if (rb && can_merge_extent_map(merge) && mergeable_maps(em, merge)) {
 		em->len += merge->len;
 		em->block_len += merge->block_len;
 		rb_erase_cached(&merge->rb_node, &tree->map);
-- 
2.40.1

[PATCH 11/11] btrfs: use the flags of an extent map to identify the compression type

[fdmanana]

From: Filipe Manana <fdmanana@suse.com>

Currently, in struct extent_map, we use an unsigned int (32 bits) to
identify the compression type of an extent and an unsigned long (64 bits
on a 64 bits platform, 32 bits otherwise) for flags. We are only using
6 different flags, so an unsigned long is excessive and we can use flags
to identify the compression type instead of using a dedicated 32 bits
field.

We can easily have tens or hundreds of thousands (or more) of extent maps
on busy and large filesystems, specially with compression enabled or many
or large files with tons of small extents. So it's convenient to have the
extent_map structure as small as possible in order to use less memory.

So removed the compression type field from struct extent_map, use flags
to identify the compression type and shorten the flags field from an
unsigned long to a u32. This saves 8 bytes (on 64 bits platforms) and
reduces the size of the structure from 136 bytes down to 128 bytes, using
now only two cache lines, and increases the number of extent maps we can
have per 4K page from 30 to 32. By using a u32 for the flags instead of
an unsigned long, we no longer use test_bit(), set_bit() and clear_bit(),
but that level of atomicity is not needed as most flags are never cleared
once set (before adding an extent map to the tree), and the ones that can
be cleared or set after an extent map is added to the tree, are always
performed while holding the write lock on the extent map tree, while the
reader holds a lock on the tree or tests for a flag that never changes
once the extent map is in the tree (such as compression flags).

Signed-off-by: Filipe Manana <fdmanana@suse.com>
---
 fs/btrfs/compression.c            |  4 +--
 fs/btrfs/defrag.c                 |  8 ++---
 fs/btrfs/extent_io.c              | 13 ++++---
 fs/btrfs/extent_map.c             | 51 ++++++++++++--------------
 fs/btrfs/extent_map.h             | 58 +++++++++++++++++++++++++-----
 fs/btrfs/file-item.c              |  9 ++---
 fs/btrfs/file.c                   | 10 +++---
 fs/btrfs/inode.c                  | 33 ++++++++---------
 fs/btrfs/relocation.c             |  2 +-
 fs/btrfs/tests/extent-map-tests.c |  4 +--
 fs/btrfs/tests/inode-tests.c      | 60 +++++++++++++++----------------
 fs/btrfs/tree-log.c               | 16 +++++----
 include/trace/events/btrfs.h      | 21 ++++++-----
 13 files changed, 158 insertions(+), 131 deletions(-)

diff --git a/fs/btrfs/compression.c b/fs/btrfs/compression.c
index 05595d113ff8..2d9974c283c6 100644
--- a/fs/btrfs/compression.c
+++ b/fs/btrfs/compression.c
@@ -584,7 +584,7 @@ void btrfs_submit_compressed_read(struct btrfs_bio *bbio)
 		goto out;
 	}
 
-	ASSERT(em->compress_type != BTRFS_COMPRESS_NONE);
+	ASSERT(extent_map_is_compressed(em));
 	compressed_len = em->block_len;
 
 	cb = alloc_compressed_bio(inode, file_offset, REQ_OP_READ,
@@ -596,7 +596,7 @@ void btrfs_submit_compressed_read(struct btrfs_bio *bbio)
 
 	cb->len = bbio->bio.bi_iter.bi_size;
 	cb->compressed_len = compressed_len;
-	cb->compress_type = em->compress_type;
+	cb->compress_type = extent_map_compression(em);
 	cb->orig_bbio = bbio;
 
 	free_extent_map(em);
diff --git a/fs/btrfs/defrag.c b/fs/btrfs/defrag.c
index 9bcb60c68c58..a9a068af8d6e 100644
--- a/fs/btrfs/defrag.c
+++ b/fs/btrfs/defrag.c
@@ -775,7 +775,7 @@ static struct extent_map *defrag_lookup_extent(struct inode *inode, u64 start,
 	 * this em, as either we don't care about the generation, or the
 	 * merged extent map will be rejected anyway.
 	 */
-	if (em && test_bit(EXTENT_FLAG_MERGED, &em->flags) &&
+	if (em && (em->flags & EXTENT_FLAG_MERGED) &&
 	    newer_than && em->generation >= newer_than) {
 		free_extent_map(em);
 		em = NULL;
@@ -802,7 +802,7 @@ static struct extent_map *defrag_lookup_extent(struct inode *inode, u64 start,
 static u32 get_extent_max_capacity(const struct btrfs_fs_info *fs_info,
 				   const struct extent_map *em)
 {
-	if (test_bit(EXTENT_FLAG_COMPRESSED, &em->flags))
+	if (extent_map_is_compressed(em))
 		return BTRFS_MAX_COMPRESSED;
 	return fs_info->max_extent_size;
 }
@@ -828,7 +828,7 @@ static bool defrag_check_next_extent(struct inode *inode, struct extent_map *em,
 	/* No more em or hole */
 	if (!next || next->block_start >= EXTENT_MAP_LAST_BYTE)
 		goto out;
-	if (test_bit(EXTENT_FLAG_PREALLOC, &next->flags))
+	if (next->flags & EXTENT_FLAG_PREALLOC)
 		goto out;
 	/*
 	 * If the next extent is at its max capacity, defragging current extent
@@ -998,7 +998,7 @@ static int defrag_collect_targets(struct btrfs_inode *inode,
 
 		/* Skip holes and preallocated extents. */
 		if (em->block_start == EXTENT_MAP_HOLE ||
-		    test_bit(EXTENT_FLAG_PREALLOC, &em->flags))
+		    (em->flags & EXTENT_FLAG_PREALLOC))
 			goto next;
 
 		/* Skip older extent */
diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c
index 0143bf63044c..774282a9e1d6 100644
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -1032,8 +1032,7 @@ static int btrfs_do_readpage(struct page *page, struct extent_map **em_cached,
 		BUG_ON(extent_map_end(em) <= cur);
 		BUG_ON(end < cur);
 
-		if (test_bit(EXTENT_FLAG_COMPRESSED, &em->flags))
-			compress_type = em->compress_type;
+		compress_type = extent_map_compression(em);
 
 		iosize = min(extent_map_end(em) - cur, end - cur + 1);
 		iosize = ALIGN(iosize, blocksize);
@@ -1042,7 +1041,7 @@ static int btrfs_do_readpage(struct page *page, struct extent_map **em_cached,
 		else
 			disk_bytenr = em->block_start + extent_offset;
 		block_start = em->block_start;
-		if (test_bit(EXTENT_FLAG_PREALLOC, &em->flags))
+		if (em->flags & EXTENT_FLAG_PREALLOC)
 			block_start = EXTENT_MAP_HOLE;
 
 		/*
@@ -1079,7 +1078,7 @@ static int btrfs_do_readpage(struct page *page, struct extent_map **em_cached,
 		 * is a corner case so we prioritize correctness over
 		 * non-optimal behavior (submitting 2 bios for the same extent).
 		 */
-		if (test_bit(EXTENT_FLAG_COMPRESSED, &em->flags) &&
+		if (compress_type != BTRFS_COMPRESS_NONE &&
 		    prev_em_start && *prev_em_start != (u64)-1 &&
 		    *prev_em_start != em->start)
 			force_bio_submit = true;
@@ -1358,7 +1357,7 @@ static noinline_for_stack int __extent_writepage_io(struct btrfs_inode *inode,
 		block_start = em->block_start;
 		disk_bytenr = em->block_start + extent_offset;
 
-		ASSERT(!test_bit(EXTENT_FLAG_COMPRESSED, &em->flags));
+		ASSERT(!extent_map_is_compressed(em));
 		ASSERT(block_start != EXTENT_MAP_HOLE);
 		ASSERT(block_start != EXTENT_MAP_INLINE);
 
@@ -2359,7 +2358,7 @@ int try_release_extent_mapping(struct page *page, gfp_t mask)
 				write_unlock(&map->lock);
 				break;
 			}
-			if (test_bit(EXTENT_FLAG_PINNED, &em->flags) ||
+			if ((em->flags & EXTENT_FLAG_PINNED) ||
 			    em->start != start) {
 				write_unlock(&map->lock);
 				free_extent_map(em);
@@ -2376,7 +2375,7 @@ int try_release_extent_mapping(struct page *page, gfp_t mask)
 			 * extra reference on the em.
 			 */
 			if (list_empty(&em->list) ||
-			    test_bit(EXTENT_FLAG_LOGGING, &em->flags))
+			    (em->flags & EXTENT_FLAG_LOGGING))
 				goto remove_em;
 			/*
 			 * If it's in the list of modified extents, remove it
diff --git a/fs/btrfs/extent_map.c b/fs/btrfs/extent_map.c
index 650ab88ad7dc..f9478be9011a 100644
--- a/fs/btrfs/extent_map.c
+++ b/fs/btrfs/extent_map.c
@@ -50,7 +50,6 @@ struct extent_map *alloc_extent_map(void)
 	if (!em)
 		return NULL;
 	RB_CLEAR_NODE(&em->rb_node);
-	em->compress_type = BTRFS_COMPRESS_NONE;
 	refcount_set(&em->refs, 1);
 	INIT_LIST_HEAD(&em->list);
 	return em;
@@ -189,14 +188,14 @@ static inline u64 extent_map_block_end(const struct extent_map *em)
 
 static bool can_merge_extent_map(const struct extent_map *em)
 {
-	if (test_bit(EXTENT_FLAG_PINNED, &em->flags))
+	if (em->flags & EXTENT_FLAG_PINNED)
 		return false;
 
 	/* Don't merge compressed extents, we need to know their actual size. */
-	if (test_bit(EXTENT_FLAG_COMPRESSED, &em->flags))
+	if (extent_map_is_compressed(em))
 		return false;
 
-	if (test_bit(EXTENT_FLAG_LOGGING, &em->flags))
+	if (em->flags & EXTENT_FLAG_LOGGING)
 		return false;
 
 	/*
@@ -258,7 +257,7 @@ static void try_merge_map(struct extent_map_tree *tree, struct extent_map *em)
 			em->mod_len = (em->mod_len + em->mod_start) - merge->mod_start;
 			em->mod_start = merge->mod_start;
 			em->generation = max(em->generation, merge->generation);
-			set_bit(EXTENT_FLAG_MERGED, &em->flags);
+			em->flags |= EXTENT_FLAG_MERGED;
 
 			rb_erase_cached(&merge->rb_node, &tree->map);
 			RB_CLEAR_NODE(&merge->rb_node);
@@ -276,7 +275,7 @@ static void try_merge_map(struct extent_map_tree *tree, struct extent_map *em)
 		RB_CLEAR_NODE(&merge->rb_node);
 		em->mod_len = (merge->mod_start + merge->mod_len) - em->mod_start;
 		em->generation = max(em->generation, merge->generation);
-		set_bit(EXTENT_FLAG_MERGED, &em->flags);
+		em->flags |= EXTENT_FLAG_MERGED;
 		free_extent_map(merge);
 	}
 }
@@ -319,13 +318,13 @@ int unpin_extent_cache(struct btrfs_inode *inode, u64 start, u64 len, u64 gen)
 			   em->start, start, len, gen);
 
 	em->generation = gen;
-	clear_bit(EXTENT_FLAG_PINNED, &em->flags);
+	em->flags &= ~EXTENT_FLAG_PINNED;
 	em->mod_start = em->start;
 	em->mod_len = em->len;
 
-	if (test_bit(EXTENT_FLAG_FILLING, &em->flags)) {
+	if (em->flags & EXTENT_FLAG_FILLING) {
 		prealloc = true;
-		clear_bit(EXTENT_FLAG_FILLING, &em->flags);
+		em->flags &= ~EXTENT_FLAG_FILLING;
 	}
 
 	try_merge_map(tree, em);
@@ -346,7 +345,7 @@ void clear_em_logging(struct extent_map_tree *tree, struct extent_map *em)
 {
 	lockdep_assert_held_write(&tree->lock);
 
-	clear_bit(EXTENT_FLAG_LOGGING, &em->flags);
+	em->flags &= ~EXTENT_FLAG_LOGGING;
 	if (extent_map_in_tree(em))
 		try_merge_map(tree, em);
 }
@@ -471,9 +470,9 @@ void remove_extent_mapping(struct extent_map_tree *tree, struct extent_map *em)
 {
 	lockdep_assert_held_write(&tree->lock);
 
-	WARN_ON(test_bit(EXTENT_FLAG_PINNED, &em->flags));
+	WARN_ON(em->flags & EXTENT_FLAG_PINNED);
 	rb_erase_cached(&em->rb_node, &tree->map);
-	if (!test_bit(EXTENT_FLAG_LOGGING, &em->flags))
+	if (!(em->flags & EXTENT_FLAG_LOGGING))
 		list_del_init(&em->list);
 	RB_CLEAR_NODE(&em->rb_node);
 }
@@ -485,9 +484,9 @@ static void replace_extent_mapping(struct extent_map_tree *tree,
 {
 	lockdep_assert_held_write(&tree->lock);
 
-	WARN_ON(test_bit(EXTENT_FLAG_PINNED, &cur->flags));
+	WARN_ON(cur->flags & EXTENT_FLAG_PINNED);
 	ASSERT(extent_map_in_tree(cur));
-	if (!test_bit(EXTENT_FLAG_LOGGING, &cur->flags))
+	if (!(cur->flags & EXTENT_FLAG_LOGGING))
 		list_del_init(&cur->list);
 	rb_replace_node_cached(&cur->rb_node, &new->rb_node, &tree->map);
 	RB_CLEAR_NODE(&cur->rb_node);
@@ -550,7 +549,7 @@ static noinline int merge_extent_mapping(struct extent_map_tree *em_tree,
 	em->start = start;
 	em->len = end - start;
 	if (em->block_start < EXTENT_MAP_LAST_BYTE &&
-	    !test_bit(EXTENT_FLAG_COMPRESSED, &em->flags)) {
+	    !extent_map_is_compressed(em)) {
 		em->block_start += start_diff;
 		em->block_len = em->len;
 	}
@@ -653,8 +652,7 @@ static void drop_all_extent_maps_fast(struct extent_map_tree *tree)
 
 		node = rb_first_cached(&tree->map);
 		em = rb_entry(node, struct extent_map, rb_node);
-		clear_bit(EXTENT_FLAG_PINNED, &em->flags);
-		clear_bit(EXTENT_FLAG_LOGGING, &em->flags);
+		em->flags &= ~(EXTENT_FLAG_PINNED | EXTENT_FLAG_LOGGING);
 		remove_extent_mapping(tree, em);
 		free_extent_map(em);
 		cond_resched_rwlock_write(&tree->lock);
@@ -730,19 +728,18 @@ void btrfs_drop_extent_map_range(struct btrfs_inode *inode, u64 start, u64 end,
 			}
 		}
 
-		if (skip_pinned && test_bit(EXTENT_FLAG_PINNED, &em->flags)) {
+		if (skip_pinned && (em->flags & EXTENT_FLAG_PINNED)) {
 			start = em_end;
 			goto next;
 		}
 
 		flags = em->flags;
-		clear_bit(EXTENT_FLAG_PINNED, &em->flags);
 		/*
 		 * In case we split the extent map, we want to preserve the
 		 * EXTENT_FLAG_LOGGING flag on our extent map, but we don't want
 		 * it on the new extent maps.
 		 */
-		clear_bit(EXTENT_FLAG_LOGGING, &flags);
+		em->flags &= ~(EXTENT_FLAG_PINNED | EXTENT_FLAG_LOGGING);
 		modified = !list_empty(&em->list);
 
 		/*
@@ -753,7 +750,7 @@ void btrfs_drop_extent_map_range(struct btrfs_inode *inode, u64 start, u64 end,
 			goto remove_em;
 
 		gen = em->generation;
-		compressed = test_bit(EXTENT_FLAG_COMPRESSED, &em->flags);
+		compressed = extent_map_is_compressed(em);
 
 		if (em->start < start) {
 			if (!split) {
@@ -786,7 +783,6 @@ void btrfs_drop_extent_map_range(struct btrfs_inode *inode, u64 start, u64 end,
 
 			split->generation = gen;
 			split->flags = flags;
-			split->compress_type = em->compress_type;
 			replace_extent_mapping(em_tree, em, split, modified);
 			free_extent_map(split);
 			split = split2;
@@ -803,7 +799,6 @@ void btrfs_drop_extent_map_range(struct btrfs_inode *inode, u64 start, u64 end,
 			split->len = em_end - end;
 			split->block_start = em->block_start;
 			split->flags = flags;
-			split->compress_type = em->compress_type;
 			split->generation = gen;
 
 			if (em->block_start < EXTENT_MAP_LAST_BYTE) {
@@ -969,14 +964,14 @@ int split_extent_map(struct btrfs_inode *inode, u64 start, u64 len, u64 pre,
 	}
 
 	ASSERT(em->len == len);
-	ASSERT(!test_bit(EXTENT_FLAG_COMPRESSED, &em->flags));
+	ASSERT(!extent_map_is_compressed(em));
 	ASSERT(em->block_start < EXTENT_MAP_LAST_BYTE);
-	ASSERT(test_bit(EXTENT_FLAG_PINNED, &em->flags));
-	ASSERT(!test_bit(EXTENT_FLAG_LOGGING, &em->flags));
+	ASSERT(em->flags & EXTENT_FLAG_PINNED);
+	ASSERT(!(em->flags & EXTENT_FLAG_LOGGING));
 	ASSERT(!list_empty(&em->list));
 
 	flags = em->flags;
-	clear_bit(EXTENT_FLAG_PINNED, &em->flags);
+	em->flags &= ~EXTENT_FLAG_PINNED;
 
 	/* First, replace the em with a new extent_map starting from * em->start */
 	split_pre->start = em->start;
@@ -987,7 +982,6 @@ int split_extent_map(struct btrfs_inode *inode, u64 start, u64 len, u64 pre,
 	split_pre->orig_block_len = split_pre->block_len;
 	split_pre->ram_bytes = split_pre->len;
 	split_pre->flags = flags;
-	split_pre->compress_type = em->compress_type;
 	split_pre->generation = em->generation;
 
 	replace_extent_mapping(em_tree, em, split_pre, 1);
@@ -1006,7 +1000,6 @@ int split_extent_map(struct btrfs_inode *inode, u64 start, u64 len, u64 pre,
 	split_mid->orig_block_len = split_mid->block_len;
 	split_mid->ram_bytes = split_mid->len;
 	split_mid->flags = flags;
-	split_mid->compress_type = em->compress_type;
 	split_mid->generation = em->generation;
 	add_extent_mapping(em_tree, split_mid, 1);
 
diff --git a/fs/btrfs/extent_map.h b/fs/btrfs/extent_map.h
index 44dc0cb310ea..e380fc08bbe4 100644
--- a/fs/btrfs/extent_map.h
+++ b/fs/btrfs/extent_map.h
@@ -5,6 +5,7 @@
 
 #include <linux/rbtree.h>
 #include <linux/refcount.h>
+#include "compression.h"
 
 #define EXTENT_MAP_LAST_BYTE ((u64)-4)
 #define EXTENT_MAP_HOLE ((u64)-3)
@@ -13,18 +14,24 @@
 /* bits for the extent_map::flags field */
 enum {
 	/* this entry not yet on disk, don't free it */
-	EXTENT_FLAG_PINNED,
-	EXTENT_FLAG_COMPRESSED,
+	ENUM_BIT(EXTENT_FLAG_PINNED),
+	ENUM_BIT(EXTENT_FLAG_COMPRESS_ZLIB),
+	ENUM_BIT(EXTENT_FLAG_COMPRESS_LZO),
+	ENUM_BIT(EXTENT_FLAG_COMPRESS_ZSTD),
 	/* pre-allocated extent */
-	EXTENT_FLAG_PREALLOC,
+	ENUM_BIT(EXTENT_FLAG_PREALLOC),
 	/* Logging this extent */
-	EXTENT_FLAG_LOGGING,
+	ENUM_BIT(EXTENT_FLAG_LOGGING),
 	/* Filling in a preallocated extent */
-	EXTENT_FLAG_FILLING,
+	ENUM_BIT(EXTENT_FLAG_FILLING),
 	/* This em is merged from two or more physically adjacent ems */
-	EXTENT_FLAG_MERGED,
+	ENUM_BIT(EXTENT_FLAG_MERGED),
 };
 
+/*
+ * Keep this structure as compact as possible, as we can have really large
+ * amounts of allocated extent maps at any time.
+ */
 struct extent_map {
 	struct rb_node rb_node;
 
@@ -45,9 +52,8 @@ struct extent_map {
 	 * For non-merged extents, it's from btrfs_file_extent_item::generation.
 	 */
 	u64 generation;
-	unsigned long flags;
+	u32 flags;
 	refcount_t refs;
-	unsigned int compress_type;
 	struct list_head list;
 };
 
@@ -59,6 +65,42 @@ struct extent_map_tree {
 
 struct btrfs_inode;
 
+static inline void extent_map_set_compression(struct extent_map *em,
+					      enum btrfs_compression_type type)
+{
+	if (type == BTRFS_COMPRESS_ZLIB)
+		em->flags |= EXTENT_FLAG_COMPRESS_ZLIB;
+	else if (type == BTRFS_COMPRESS_LZO)
+		em->flags |= EXTENT_FLAG_COMPRESS_LZO;
+	else if (type == BTRFS_COMPRESS_ZSTD)
+		em->flags |= EXTENT_FLAG_COMPRESS_ZSTD;
+}
+
+static inline enum btrfs_compression_type extent_map_compression(const struct extent_map *em)
+{
+	if (em->flags & EXTENT_FLAG_COMPRESS_ZLIB)
+		return BTRFS_COMPRESS_ZLIB;
+
+	if (em->flags & EXTENT_FLAG_COMPRESS_LZO)
+		return BTRFS_COMPRESS_LZO;
+
+	if (em->flags & EXTENT_FLAG_COMPRESS_ZSTD)
+		return BTRFS_COMPRESS_ZSTD;
+
+	return BTRFS_COMPRESS_NONE;
+}
+
+/*
+ * More efficient way to determine if extent is compressed, instead of using
+ * 'extent_map_compression() != BTRFS_COMPRESS_NONE'.
+ */
+static inline bool extent_map_is_compressed(const struct extent_map *em)
+{
+	return (em->flags & (EXTENT_FLAG_COMPRESS_ZLIB |
+			     EXTENT_FLAG_COMPRESS_LZO |
+			     EXTENT_FLAG_COMPRESS_ZSTD)) != 0;
+}
+
 static inline int extent_map_in_tree(const struct extent_map *em)
 {
 	return !RB_EMPTY_NODE(&em->rb_node);
diff --git a/fs/btrfs/file-item.c b/fs/btrfs/file-item.c
index 45cae356e89b..ff0030d26744 100644
--- a/fs/btrfs/file-item.c
+++ b/fs/btrfs/file-item.c
@@ -1294,8 +1294,7 @@ void btrfs_extent_item_to_extent_map(struct btrfs_inode *inode,
 			return;
 		}
 		if (compress_type != BTRFS_COMPRESS_NONE) {
-			set_bit(EXTENT_FLAG_COMPRESSED, &em->flags);
-			em->compress_type = compress_type;
+			extent_map_set_compression(em, compress_type);
 			em->block_start = bytenr;
 			em->block_len = em->orig_block_len;
 		} else {
@@ -1303,7 +1302,7 @@ void btrfs_extent_item_to_extent_map(struct btrfs_inode *inode,
 			em->block_start = bytenr;
 			em->block_len = em->len;
 			if (type == BTRFS_FILE_EXTENT_PREALLOC)
-				set_bit(EXTENT_FLAG_PREALLOC, &em->flags);
+				em->flags |= EXTENT_FLAG_PREALLOC;
 		}
 	} else if (type == BTRFS_FILE_EXTENT_INLINE) {
 		em->block_start = EXTENT_MAP_INLINE;
@@ -1315,9 +1314,7 @@ void btrfs_extent_item_to_extent_map(struct btrfs_inode *inode,
 		 */
 		em->orig_start = EXTENT_MAP_HOLE;
 		em->block_len = (u64)-1;
-		em->compress_type = compress_type;
-		if (compress_type != BTRFS_COMPRESS_NONE)
-			set_bit(EXTENT_FLAG_COMPRESSED, &em->flags);
+		extent_map_set_compression(em, compress_type);
 	} else {
 		btrfs_err(fs_info,
 			  "unknown file extent item type %d, inode %llu, offset %llu, "
diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c
index e9c4b947a5aa..15c5fc0db5a6 100644
--- a/fs/btrfs/file.c
+++ b/fs/btrfs/file.c
@@ -2150,7 +2150,6 @@ static int fill_holes(struct btrfs_trans_handle *trans,
 		hole_em->block_start = EXTENT_MAP_HOLE;
 		hole_em->block_len = 0;
 		hole_em->orig_block_len = 0;
-		hole_em->compress_type = BTRFS_COMPRESS_NONE;
 		hole_em->generation = trans->transid;
 
 		ret = btrfs_replace_extent_map_range(inode, hole_em, true);
@@ -2839,7 +2838,7 @@ static int btrfs_zero_range_check_range_boundary(struct btrfs_inode *inode,
 
 	if (em->block_start == EXTENT_MAP_HOLE)
 		ret = RANGE_BOUNDARY_HOLE;
-	else if (test_bit(EXTENT_FLAG_PREALLOC, &em->flags))
+	else if (em->flags & EXTENT_FLAG_PREALLOC)
 		ret = RANGE_BOUNDARY_PREALLOC_EXTENT;
 	else
 		ret = RANGE_BOUNDARY_WRITTEN_EXTENT;
@@ -2879,8 +2878,7 @@ static int btrfs_zero_range(struct inode *inode,
 	 * extents and holes, we drop all the existing extents and allocate a
 	 * new prealloc extent, so that we get a larger contiguous disk extent.
 	 */
-	if (em->start <= alloc_start &&
-	    test_bit(EXTENT_FLAG_PREALLOC, &em->flags)) {
+	if (em->start <= alloc_start && (em->flags & EXTENT_FLAG_PREALLOC)) {
 		const u64 em_end = em->start + em->len;
 
 		if (em_end >= offset + len) {
@@ -2915,7 +2913,7 @@ static int btrfs_zero_range(struct inode *inode,
 			goto out;
 		}
 
-		if (test_bit(EXTENT_FLAG_PREALLOC, &em->flags)) {
+		if (em->flags & EXTENT_FLAG_PREALLOC) {
 			free_extent_map(em);
 			ret = btrfs_fallocate_update_isize(inode, offset + len,
 							   mode);
@@ -3136,7 +3134,7 @@ static long btrfs_fallocate(struct file *file, int mode,
 		last_byte = ALIGN(last_byte, blocksize);
 		if (em->block_start == EXTENT_MAP_HOLE ||
 		    (cur_offset >= inode->i_size &&
-		     !test_bit(EXTENT_FLAG_PREALLOC, &em->flags))) {
+		     !(em->flags & EXTENT_FLAG_PREALLOC))) {
 			const u64 range_len = last_byte - cur_offset;
 
 			ret = add_falloc_range(&reserve_list, cur_offset, range_len);
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index f7f48c2f0276..9ccff342ed42 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -4898,7 +4898,7 @@ int btrfs_cont_expand(struct btrfs_inode *inode, loff_t oldsize, loff_t size)
 		last_byte = ALIGN(last_byte, fs_info->sectorsize);
 		hole_size = last_byte - cur_offset;
 
-		if (!test_bit(EXTENT_FLAG_PREALLOC, &em->flags)) {
+		if (!(em->flags & EXTENT_FLAG_PREALLOC)) {
 			struct extent_map *hole_em;
 
 			err = maybe_insert_hole(inode, cur_offset, hole_size);
@@ -4926,7 +4926,6 @@ int btrfs_cont_expand(struct btrfs_inode *inode, loff_t oldsize, loff_t size)
 			hole_em->block_len = 0;
 			hole_em->orig_block_len = 0;
 			hole_em->ram_bytes = hole_size;
-			hole_em->compress_type = BTRFS_COMPRESS_NONE;
 			hole_em->generation = btrfs_get_fs_generation(fs_info);
 
 			err = btrfs_replace_extent_map_range(inode, hole_em, true);
@@ -7274,13 +7273,11 @@ static struct extent_map *create_io_em(struct btrfs_inode *inode, u64 start,
 	em->orig_block_len = orig_block_len;
 	em->ram_bytes = ram_bytes;
 	em->generation = -1;
-	set_bit(EXTENT_FLAG_PINNED, &em->flags);
-	if (type == BTRFS_ORDERED_PREALLOC) {
-		set_bit(EXTENT_FLAG_FILLING, &em->flags);
-	} else if (type == BTRFS_ORDERED_COMPRESSED) {
-		set_bit(EXTENT_FLAG_COMPRESSED, &em->flags);
-		em->compress_type = compress_type;
-	}
+	em->flags |= EXTENT_FLAG_PINNED;
+	if (type == BTRFS_ORDERED_PREALLOC)
+		em->flags |= EXTENT_FLAG_FILLING;
+	else if (type == BTRFS_ORDERED_COMPRESSED)
+		extent_map_set_compression(em, compress_type);
 
 	ret = btrfs_replace_extent_map_range(inode, em, true);
 	if (ret) {
@@ -7320,10 +7317,10 @@ static int btrfs_get_blocks_direct_write(struct extent_map **map,
 	 * just use the extent.
 	 *
 	 */
-	if (test_bit(EXTENT_FLAG_PREALLOC, &em->flags) ||
+	if ((em->flags & EXTENT_FLAG_PREALLOC) ||
 	    ((BTRFS_I(inode)->flags & BTRFS_INODE_NODATACOW) &&
 	     em->block_start != EXTENT_MAP_HOLE)) {
-		if (test_bit(EXTENT_FLAG_PREALLOC, &em->flags))
+		if (em->flags & EXTENT_FLAG_PREALLOC)
 			type = BTRFS_ORDERED_PREALLOC;
 		else
 			type = BTRFS_ORDERED_NOCOW;
@@ -7558,7 +7555,7 @@ static int btrfs_dio_iomap_begin(struct inode *inode, loff_t start,
 	 * to buffered IO.  Don't blame me, this is the price we pay for using
 	 * the generic code.
 	 */
-	if (test_bit(EXTENT_FLAG_COMPRESSED, &em->flags) ||
+	if (extent_map_is_compressed(em) ||
 	    em->block_start == EXTENT_MAP_INLINE) {
 		free_extent_map(em);
 		/*
@@ -7654,7 +7651,7 @@ static int btrfs_dio_iomap_begin(struct inode *inode, loff_t start,
 	 * that, since we have locked only the parts we are performing I/O in.
 	 */
 	if ((em->block_start == EXTENT_MAP_HOLE) ||
-	    (test_bit(EXTENT_FLAG_PREALLOC, &em->flags) && !write)) {
+	    ((em->flags & EXTENT_FLAG_PREALLOC) && !write)) {
 		iomap->addr = IOMAP_NULL_ADDR;
 		iomap->type = IOMAP_HOLE;
 	} else {
@@ -9654,7 +9651,7 @@ static int __btrfs_prealloc_file_range(struct inode *inode, int mode,
 		em->block_len = ins.offset;
 		em->orig_block_len = ins.offset;
 		em->ram_bytes = ins.offset;
-		set_bit(EXTENT_FLAG_PREALLOC, &em->flags);
+		em->flags |= EXTENT_FLAG_PREALLOC;
 		em->generation = trans->transid;
 
 		ret = btrfs_replace_extent_map_range(BTRFS_I(inode), em, true);
@@ -10135,12 +10132,12 @@ ssize_t btrfs_encoded_read(struct kiocb *iocb, struct iov_iter *iter,
 	encoded->len = min_t(u64, extent_map_end(em),
 			     inode->vfs_inode.i_size) - iocb->ki_pos;
 	if (em->block_start == EXTENT_MAP_HOLE ||
-	    test_bit(EXTENT_FLAG_PREALLOC, &em->flags)) {
+	    (em->flags & EXTENT_FLAG_PREALLOC)) {
 		disk_bytenr = EXTENT_MAP_HOLE;
 		count = min_t(u64, count, encoded->len);
 		encoded->len = count;
 		encoded->unencoded_len = count;
-	} else if (test_bit(EXTENT_FLAG_COMPRESSED, &em->flags)) {
+	} else if (extent_map_is_compressed(em)) {
 		disk_bytenr = em->block_start;
 		/*
 		 * Bail if the buffer isn't large enough to return the whole
@@ -10155,7 +10152,7 @@ ssize_t btrfs_encoded_read(struct kiocb *iocb, struct iov_iter *iter,
 		encoded->unencoded_len = em->ram_bytes;
 		encoded->unencoded_offset = iocb->ki_pos - em->orig_start;
 		ret = btrfs_encoded_io_compression_from_extent(fs_info,
-							     em->compress_type);
+							       extent_map_compression(em));
 		if (ret < 0)
 			goto out_em;
 		encoded->compression = ret;
@@ -10703,7 +10700,7 @@ static int btrfs_swap_activate(struct swap_info_struct *sis, struct file *file,
 			ret = -EINVAL;
 			goto out;
 		}
-		if (test_bit(EXTENT_FLAG_COMPRESSED, &em->flags)) {
+		if (extent_map_is_compressed(em)) {
 			btrfs_warn(fs_info, "swapfile must not be compressed");
 			ret = -EINVAL;
 			goto out;
diff --git a/fs/btrfs/relocation.c b/fs/btrfs/relocation.c
index f5d9e5f74a52..78c2770eb52f 100644
--- a/fs/btrfs/relocation.c
+++ b/fs/btrfs/relocation.c
@@ -2951,7 +2951,7 @@ static noinline_for_stack int setup_relocation_extent_mapping(struct inode *inod
 	em->len = end + 1 - start;
 	em->block_len = em->len;
 	em->block_start = block_start;
-	set_bit(EXTENT_FLAG_PINNED, &em->flags);
+	em->flags |= EXTENT_FLAG_PINNED;
 
 	lock_extent(&BTRFS_I(inode)->io_tree, start, end, &cached_state);
 	ret = btrfs_replace_extent_map_range(BTRFS_I(inode), em, false);
diff --git a/fs/btrfs/tests/extent-map-tests.c b/fs/btrfs/tests/extent-map-tests.c
index 59bbf714225c..253cce7ffecf 100644
--- a/fs/btrfs/tests/extent-map-tests.c
+++ b/fs/btrfs/tests/extent-map-tests.c
@@ -480,7 +480,7 @@ static int add_compressed_extent(struct btrfs_fs_info *fs_info,
 	em->len = len;
 	em->block_start = block_start;
 	em->block_len = SZ_4K;
-	set_bit(EXTENT_FLAG_COMPRESSED, &em->flags);
+	em->flags |= EXTENT_FLAG_COMPRESS_ZLIB;
 	write_lock(&em_tree->lock);
 	ret = btrfs_add_extent_mapping(fs_info, em_tree, &em, em->start, em->len);
 	write_unlock(&em_tree->lock);
@@ -763,7 +763,7 @@ static int test_case_7(struct btrfs_fs_info *fs_info)
 	em->len = SZ_16K;
 	em->block_start = 0;
 	em->block_len = SZ_4K;
-	set_bit(EXTENT_FLAG_PINNED, &em->flags);
+	em->flags |= EXTENT_FLAG_PINNED;
 	write_lock(&em_tree->lock);
 	ret = btrfs_add_extent_mapping(fs_info, em_tree, &em, em->start, em->len);
 	write_unlock(&em_tree->lock);
diff --git a/fs/btrfs/tests/inode-tests.c b/fs/btrfs/tests/inode-tests.c
index 492d69d2fa73..9957de9f7806 100644
--- a/fs/btrfs/tests/inode-tests.c
+++ b/fs/btrfs/tests/inode-tests.c
@@ -211,9 +211,9 @@ static void setup_file_extents(struct btrfs_root *root, u32 sectorsize)
 		      sectorsize, BTRFS_FILE_EXTENT_REG, 0, slot);
 }
 
-static unsigned long prealloc_only = 0;
-static unsigned long compressed_only = 0;
-static unsigned long vacancy_only = 0;
+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)
 {
@@ -305,7 +305,7 @@ static noinline int test_btrfs_get_extent(u32 sectorsize, u32 nodesize)
 		goto out;
 	}
 	if (em->flags != 0) {
-		test_err("unexpected flags set, want 0 have %lu", em->flags);
+		test_err("unexpected flags set, want 0 have %u", em->flags);
 		goto out;
 	}
 	/*
@@ -332,7 +332,7 @@ static noinline int test_btrfs_get_extent(u32 sectorsize, u32 nodesize)
 		goto out;
 	}
 	if (em->flags != 0) {
-		test_err("unexpected flags set, want 0 have %lu", em->flags);
+		test_err("unexpected flags set, want 0 have %u", em->flags);
 		goto out;
 	}
 	offset = em->start + em->len;
@@ -355,7 +355,7 @@ static noinline int test_btrfs_get_extent(u32 sectorsize, u32 nodesize)
 		goto out;
 	}
 	if (em->flags != 0) {
-		test_err("unexpected flags set, want 0 have %lu", em->flags);
+		test_err("unexpected flags set, want 0 have %u", em->flags);
 		goto out;
 	}
 	if (em->orig_start != em->start) {
@@ -383,7 +383,7 @@ static noinline int test_btrfs_get_extent(u32 sectorsize, u32 nodesize)
 		goto out;
 	}
 	if (em->flags != 0) {
-		test_err("unexpected flags set, want 0 have %lu", em->flags);
+		test_err("unexpected flags set, want 0 have %u", em->flags);
 		goto out;
 	}
 	if (em->orig_start != em->start) {
@@ -412,7 +412,7 @@ static noinline int test_btrfs_get_extent(u32 sectorsize, u32 nodesize)
 		goto out;
 	}
 	if (em->flags != 0) {
-		test_err("unexpected flags set, want 0 have %lu", em->flags);
+		test_err("unexpected flags set, want 0 have %u", em->flags);
 		goto out;
 	}
 	offset = em->start + em->len;
@@ -434,7 +434,7 @@ static noinline int test_btrfs_get_extent(u32 sectorsize, u32 nodesize)
 		goto out;
 	}
 	if (em->flags != 0) {
-		test_err("unexpected flags set, want 0 have %lu", em->flags);
+		test_err("unexpected flags set, want 0 have %u", em->flags);
 		goto out;
 	}
 	if (em->orig_start != orig_start) {
@@ -468,7 +468,7 @@ static noinline int test_btrfs_get_extent(u32 sectorsize, u32 nodesize)
 		goto out;
 	}
 	if (em->flags != prealloc_only) {
-		test_err("unexpected flags set, want %lu have %lu",
+		test_err("unexpected flags set, want %u have %u",
 			 prealloc_only, em->flags);
 		goto out;
 	}
@@ -497,7 +497,7 @@ static noinline int test_btrfs_get_extent(u32 sectorsize, u32 nodesize)
 		goto out;
 	}
 	if (em->flags != prealloc_only) {
-		test_err("unexpected flags set, want %lu have %lu",
+		test_err("unexpected flags set, want %u have %u",
 			 prealloc_only, em->flags);
 		goto out;
 	}
@@ -527,7 +527,7 @@ static noinline int test_btrfs_get_extent(u32 sectorsize, u32 nodesize)
 		goto out;
 	}
 	if (em->flags != 0) {
-		test_err("unexpected flags set, want 0 have %lu", em->flags);
+		test_err("unexpected flags set, want 0 have %u", em->flags);
 		goto out;
 	}
 	if (em->orig_start != orig_start) {
@@ -560,7 +560,7 @@ static noinline int test_btrfs_get_extent(u32 sectorsize, u32 nodesize)
 		goto out;
 	}
 	if (em->flags != prealloc_only) {
-		test_err("unexpected flags set, want %lu have %lu",
+		test_err("unexpected flags set, want %u have %u",
 			 prealloc_only, em->flags);
 		goto out;
 	}
@@ -595,7 +595,7 @@ static noinline int test_btrfs_get_extent(u32 sectorsize, u32 nodesize)
 		goto out;
 	}
 	if (em->flags != compressed_only) {
-		test_err("unexpected flags set, want %lu have %lu",
+		test_err("unexpected flags set, want %u have %u",
 			 compressed_only, em->flags);
 		goto out;
 	}
@@ -604,9 +604,9 @@ static noinline int test_btrfs_get_extent(u32 sectorsize, u32 nodesize)
 			 em->start, em->orig_start);
 		goto out;
 	}
-	if (em->compress_type != BTRFS_COMPRESS_ZLIB) {
+	if (extent_map_compression(em) != BTRFS_COMPRESS_ZLIB) {
 		test_err("unexpected compress type, wanted %d, got %d",
-			 BTRFS_COMPRESS_ZLIB, em->compress_type);
+			 BTRFS_COMPRESS_ZLIB, extent_map_compression(em));
 		goto out;
 	}
 	offset = em->start + em->len;
@@ -629,7 +629,7 @@ static noinline int test_btrfs_get_extent(u32 sectorsize, u32 nodesize)
 		goto out;
 	}
 	if (em->flags != compressed_only) {
-		test_err("unexpected flags set, want %lu have %lu",
+		test_err("unexpected flags set, want %u have %u",
 			 compressed_only, em->flags);
 		goto out;
 	}
@@ -638,9 +638,9 @@ static noinline int test_btrfs_get_extent(u32 sectorsize, u32 nodesize)
 			 em->start, em->orig_start);
 		goto out;
 	}
-	if (em->compress_type != BTRFS_COMPRESS_ZLIB) {
+	if (extent_map_compression(em) != BTRFS_COMPRESS_ZLIB) {
 		test_err("unexpected compress type, wanted %d, got %d",
-			 BTRFS_COMPRESS_ZLIB, em->compress_type);
+			 BTRFS_COMPRESS_ZLIB, extent_map_compression(em));
 		goto out;
 	}
 	disk_bytenr = em->block_start;
@@ -664,7 +664,7 @@ static noinline int test_btrfs_get_extent(u32 sectorsize, u32 nodesize)
 		goto out;
 	}
 	if (em->flags != 0) {
-		test_err("unexpected flags set, want 0 have %lu", em->flags);
+		test_err("unexpected flags set, want 0 have %u", em->flags);
 		goto out;
 	}
 	if (em->orig_start != em->start) {
@@ -692,7 +692,7 @@ static noinline int test_btrfs_get_extent(u32 sectorsize, u32 nodesize)
 		goto out;
 	}
 	if (em->flags != compressed_only) {
-		test_err("unexpected flags set, want %lu have %lu",
+		test_err("unexpected flags set, want %u have %u",
 			 compressed_only, em->flags);
 		goto out;
 	}
@@ -701,9 +701,9 @@ static noinline int test_btrfs_get_extent(u32 sectorsize, u32 nodesize)
 			 em->start, orig_start);
 		goto out;
 	}
-	if (em->compress_type != BTRFS_COMPRESS_ZLIB) {
+	if (extent_map_compression(em) != BTRFS_COMPRESS_ZLIB) {
 		test_err("unexpected compress type, wanted %d, got %d",
-			 BTRFS_COMPRESS_ZLIB, em->compress_type);
+			 BTRFS_COMPRESS_ZLIB, extent_map_compression(em));
 		goto out;
 	}
 	offset = em->start + em->len;
@@ -726,7 +726,7 @@ static noinline int test_btrfs_get_extent(u32 sectorsize, u32 nodesize)
 		goto out;
 	}
 	if (em->flags != 0) {
-		test_err("unexpected flags set, want 0 have %lu", em->flags);
+		test_err("unexpected flags set, want 0 have %u", em->flags);
 		goto out;
 	}
 	if (em->orig_start != em->start) {
@@ -758,7 +758,7 @@ static noinline int test_btrfs_get_extent(u32 sectorsize, u32 nodesize)
 		goto out;
 	}
 	if (em->flags != vacancy_only) {
-		test_err("unexpected flags set, want %lu have %lu",
+		test_err("unexpected flags set, want %u have %u",
 			 vacancy_only, em->flags);
 		goto out;
 	}
@@ -786,7 +786,7 @@ static noinline int test_btrfs_get_extent(u32 sectorsize, u32 nodesize)
 		goto out;
 	}
 	if (em->flags != 0) {
-		test_err("unexpected flags set, want 0 have %lu", em->flags);
+		test_err("unexpected flags set, want 0 have %u", em->flags);
 		goto out;
 	}
 	if (em->orig_start != em->start) {
@@ -866,7 +866,7 @@ static int test_hole_first(u32 sectorsize, u32 nodesize)
 		goto out;
 	}
 	if (em->flags != vacancy_only) {
-		test_err("wrong flags, wanted %lu, have %lu", vacancy_only,
+		test_err("wrong flags, wanted %u, have %u", vacancy_only,
 			 em->flags);
 		goto out;
 	}
@@ -888,7 +888,7 @@ static int test_hole_first(u32 sectorsize, u32 nodesize)
 		goto out;
 	}
 	if (em->flags != 0) {
-		test_err("unexpected flags set, wanted 0 got %lu",
+		test_err("unexpected flags set, wanted 0 got %u",
 			 em->flags);
 		goto out;
 	}
@@ -1095,8 +1095,8 @@ int btrfs_test_inodes(u32 sectorsize, u32 nodesize)
 
 	test_msg("running inode tests");
 
-	set_bit(EXTENT_FLAG_COMPRESSED, &compressed_only);
-	set_bit(EXTENT_FLAG_PREALLOC, &prealloc_only);
+	compressed_only |= EXTENT_FLAG_COMPRESS_ZLIB;
+	prealloc_only |= EXTENT_FLAG_PREALLOC;
 
 	ret = test_btrfs_get_extent(sectorsize, nodesize);
 	if (ret)
diff --git a/fs/btrfs/tree-log.c b/fs/btrfs/tree-log.c
index bee065851185..331fc7429952 100644
--- a/fs/btrfs/tree-log.c
+++ b/fs/btrfs/tree-log.c
@@ -4519,7 +4519,7 @@ static int log_extent_csums(struct btrfs_trans_handle *trans,
 	int ret = 0;
 
 	if (inode->flags & BTRFS_INODE_NODATASUM ||
-	    test_bit(EXTENT_FLAG_PREALLOC, &em->flags) ||
+	    (em->flags & EXTENT_FLAG_PREALLOC) ||
 	    em->block_start == EXTENT_MAP_HOLE)
 		return 0;
 
@@ -4582,7 +4582,7 @@ static int log_extent_csums(struct btrfs_trans_handle *trans,
 		return 0;
 
 	/* If we're compressed we have to save the entire range of csums. */
-	if (em->compress_type) {
+	if (extent_map_is_compressed(em)) {
 		csum_offset = 0;
 		csum_len = max(em->block_len, em->orig_block_len);
 	} else {
@@ -4622,18 +4622,20 @@ static int log_one_extent(struct btrfs_trans_handle *trans,
 	struct btrfs_file_extent_item fi = { 0 };
 	struct extent_buffer *leaf;
 	struct btrfs_key key;
+	enum btrfs_compression_type compress_type;
 	u64 extent_offset = em->start - em->orig_start;
 	u64 block_len;
 	int ret;
 
 	btrfs_set_stack_file_extent_generation(&fi, trans->transid);
-	if (test_bit(EXTENT_FLAG_PREALLOC, &em->flags))
+	if (em->flags & EXTENT_FLAG_PREALLOC)
 		btrfs_set_stack_file_extent_type(&fi, BTRFS_FILE_EXTENT_PREALLOC);
 	else
 		btrfs_set_stack_file_extent_type(&fi, BTRFS_FILE_EXTENT_REG);
 
 	block_len = max(em->block_len, em->orig_block_len);
-	if (em->compress_type != BTRFS_COMPRESS_NONE) {
+	compress_type = extent_map_compression(em);
+	if (compress_type != BTRFS_COMPRESS_NONE) {
 		btrfs_set_stack_file_extent_disk_bytenr(&fi, em->block_start);
 		btrfs_set_stack_file_extent_disk_num_bytes(&fi, block_len);
 	} else if (em->block_start < EXTENT_MAP_LAST_BYTE) {
@@ -4645,7 +4647,7 @@ static int log_one_extent(struct btrfs_trans_handle *trans,
 	btrfs_set_stack_file_extent_offset(&fi, extent_offset);
 	btrfs_set_stack_file_extent_num_bytes(&fi, em->len);
 	btrfs_set_stack_file_extent_ram_bytes(&fi, em->ram_bytes);
-	btrfs_set_stack_file_extent_compression(&fi, em->compress_type);
+	btrfs_set_stack_file_extent_compression(&fi, compress_type);
 
 	ret = log_extent_csums(trans, inode, log, em, ctx);
 	if (ret)
@@ -4858,13 +4860,13 @@ static int btrfs_log_changed_extents(struct btrfs_trans_handle *trans,
 			continue;
 
 		/* We log prealloc extents beyond eof later. */
-		if (test_bit(EXTENT_FLAG_PREALLOC, &em->flags) &&
+		if ((em->flags & EXTENT_FLAG_PREALLOC) &&
 		    em->start >= i_size_read(&inode->vfs_inode))
 			continue;
 
 		/* Need a ref to keep it from getting evicted from cache */
 		refcount_inc(&em->refs);
-		set_bit(EXTENT_FLAG_LOGGING, &em->flags);
+		em->flags |= EXTENT_FLAG_LOGGING;
 		list_add_tail(&em->list, &extents);
 		num++;
 	}
diff --git a/include/trace/events/btrfs.h b/include/trace/events/btrfs.h
index 31da1456f953..90b0222390e5 100644
--- a/include/trace/events/btrfs.h
+++ b/include/trace/events/btrfs.h
@@ -272,11 +272,13 @@ DEFINE_EVENT(btrfs__inode, btrfs_inode_evict,
 
 #define show_map_flags(flag)						\
 	__print_flags(flag, "|",					\
-		{ (1 << EXTENT_FLAG_PINNED), 		"PINNED" 	},\
-		{ (1 << EXTENT_FLAG_COMPRESSED), 	"COMPRESSED" 	},\
-		{ (1 << EXTENT_FLAG_PREALLOC), 		"PREALLOC" 	},\
-		{ (1 << EXTENT_FLAG_LOGGING),	 	"LOGGING" 	},\
-		{ (1 << EXTENT_FLAG_FILLING),		"FILLING"	})
+		{ EXTENT_FLAG_PINNED,		"PINNED"	},\
+		{ EXTENT_FLAG_COMPRESS_ZLIB,	"COMPRESS_ZLIB"	},\
+		{ EXTENT_FLAG_COMPRESS_LZO,	"COMPRESS_LZO"	},\
+		{ EXTENT_FLAG_COMPRESS_ZSTD,	"COMPRESS_ZSTD"	},\
+		{ EXTENT_FLAG_PREALLOC,		"PREALLOC"	},\
+		{ EXTENT_FLAG_LOGGING,		"LOGGING"	},\
+		{ EXTENT_FLAG_FILLING,		"FILLING"	})
 
 TRACE_EVENT_CONDITION(btrfs_get_extent,
 
@@ -295,9 +297,8 @@ TRACE_EVENT_CONDITION(btrfs_get_extent,
 		__field(	u64,  orig_start	)
 		__field(	u64,  block_start	)
 		__field(	u64,  block_len		)
-		__field(	unsigned long,  flags	)
+		__field(	u32,  flags		)
 		__field(	int,  refs		)
-		__field(	unsigned int,  compress_type	)
 	),
 
 	TP_fast_assign_btrfs(root->fs_info,
@@ -310,13 +311,11 @@ TRACE_EVENT_CONDITION(btrfs_get_extent,
 		__entry->block_len	= map->block_len;
 		__entry->flags		= map->flags;
 		__entry->refs		= refcount_read(&map->refs);
-		__entry->compress_type	= map->compress_type;
 	),
 
 	TP_printk_btrfs("root=%llu(%s) ino=%llu start=%llu len=%llu "
 		  "orig_start=%llu block_start=%llu(%s) "
-		  "block_len=%llu flags=%s refs=%u "
-		  "compress_type=%u",
+		  "block_len=%llu flags=%s refs=%u",
 		  show_root_type(__entry->root_objectid),
 		  __entry->ino,
 		  __entry->start,
@@ -325,7 +324,7 @@ TRACE_EVENT_CONDITION(btrfs_get_extent,
 		  show_map_type(__entry->block_start),
 		  __entry->block_len,
 		  show_map_flags(__entry->flags),
-		  __entry->refs, __entry->compress_type)
+		  __entry->refs)
 );
 
 TRACE_EVENT(btrfs_handle_em_exist,
-- 
2.40.1

Re: [PATCH 11/11] btrfs: use the flags of an extent map to identify the compression type

[David Sterba]

On Mon, Dec 04, 2023 at 04:20:33PM +0000, fdmanana@kernel.org wrote:
> +	else if (type == BTRFS_COMPRESS_LZO)
> +		em->flags |= EXTENT_FLAG_COMPRESS_LZO;
> +	else if (type == BTRFS_COMPRESS_ZSTD)
> +		em->flags |= EXTENT_FLAG_COMPRESS_ZSTD;
> +}
> +
> +static inline enum btrfs_compression_type extent_map_compression(const struct extent_map *em)
> +{
> +	if (em->flags & EXTENT_FLAG_COMPRESS_ZLIB)
> +		return BTRFS_COMPRESS_ZLIB;
> +
> +	if (em->flags & EXTENT_FLAG_COMPRESS_LZO)
> +		return BTRFS_COMPRESS_LZO;
> +
> +	if (em->flags & EXTENT_FLAG_COMPRESS_ZSTD)
> +		return BTRFS_COMPRESS_ZSTD;
> +
> +	return BTRFS_COMPRESS_NONE;
> +}
> +
> +/*
> + * More efficient way to determine if extent is compressed, instead of using
> + * 'extent_map_compression() != BTRFS_COMPRESS_NONE'.
> + */
> +static inline bool extent_map_is_compressed(const struct extent_map *em)
> +{
> +	return (em->flags & (EXTENT_FLAG_COMPRESS_ZLIB |
> +			     EXTENT_FLAG_COMPRESS_LZO |
> +			     EXTENT_FLAG_COMPRESS_ZSTD)) != 0;

As a minor optimizations, you could add another bit flag when any of the
zlib/lzo/std is set and test just that.

Otherwise, I like the changes and space savings.

Re: [PATCH 11/11] btrfs: use the flags of an extent map to identify the compression type

[Filipe Manana]

On Tue, Dec 5, 2023 at 2:50 PM David Sterba <dsterba@suse.cz> wrote:
>
> On Mon, Dec 04, 2023 at 04:20:33PM +0000, fdmanana@kernel.org wrote:
> > +     else if (type == BTRFS_COMPRESS_LZO)
> > +             em->flags |= EXTENT_FLAG_COMPRESS_LZO;
> > +     else if (type == BTRFS_COMPRESS_ZSTD)
> > +             em->flags |= EXTENT_FLAG_COMPRESS_ZSTD;
> > +}
> > +
> > +static inline enum btrfs_compression_type extent_map_compression(const struct extent_map *em)
> > +{
> > +     if (em->flags & EXTENT_FLAG_COMPRESS_ZLIB)
> > +             return BTRFS_COMPRESS_ZLIB;
> > +
> > +     if (em->flags & EXTENT_FLAG_COMPRESS_LZO)
> > +             return BTRFS_COMPRESS_LZO;
> > +
> > +     if (em->flags & EXTENT_FLAG_COMPRESS_ZSTD)
> > +             return BTRFS_COMPRESS_ZSTD;
> > +
> > +     return BTRFS_COMPRESS_NONE;
> > +}
> > +
> > +/*
> > + * More efficient way to determine if extent is compressed, instead of using
> > + * 'extent_map_compression() != BTRFS_COMPRESS_NONE'.
> > + */
> > +static inline bool extent_map_is_compressed(const struct extent_map *em)
> > +{
> > +     return (em->flags & (EXTENT_FLAG_COMPRESS_ZLIB |
> > +                          EXTENT_FLAG_COMPRESS_LZO |
> > +                          EXTENT_FLAG_COMPRESS_ZSTD)) != 0;
>
> As a minor optimizations, you could add another bit flag when any of the
> zlib/lzo/std is set and test just that.

How is that an optimization? The compiler ORs those compression flags
at compile time, it would be equivalent.

>
> Otherwise, I like the changes and space savings.

Re: [PATCH 11/11] btrfs: use the flags of an extent map to identify the compression type

[David Sterba]

On Tue, Dec 05, 2023 at 03:01:28PM +0000, Filipe Manana wrote:
> On Tue, Dec 5, 2023 at 2:50 PM David Sterba <dsterba@suse.cz> wrote:
> >
> > On Mon, Dec 04, 2023 at 04:20:33PM +0000, fdmanana@kernel.org wrote:
> > > +     else if (type == BTRFS_COMPRESS_LZO)
> > > +             em->flags |= EXTENT_FLAG_COMPRESS_LZO;
> > > +     else if (type == BTRFS_COMPRESS_ZSTD)
> > > +             em->flags |= EXTENT_FLAG_COMPRESS_ZSTD;
> > > +}
> > > +
> > > +static inline enum btrfs_compression_type extent_map_compression(const struct extent_map *em)
> > > +{
> > > +     if (em->flags & EXTENT_FLAG_COMPRESS_ZLIB)
> > > +             return BTRFS_COMPRESS_ZLIB;
> > > +
> > > +     if (em->flags & EXTENT_FLAG_COMPRESS_LZO)
> > > +             return BTRFS_COMPRESS_LZO;
> > > +
> > > +     if (em->flags & EXTENT_FLAG_COMPRESS_ZSTD)
> > > +             return BTRFS_COMPRESS_ZSTD;
> > > +
> > > +     return BTRFS_COMPRESS_NONE;
> > > +}
> > > +
> > > +/*
> > > + * More efficient way to determine if extent is compressed, instead of using
> > > + * 'extent_map_compression() != BTRFS_COMPRESS_NONE'.
> > > + */
> > > +static inline bool extent_map_is_compressed(const struct extent_map *em)
> > > +{
> > > +     return (em->flags & (EXTENT_FLAG_COMPRESS_ZLIB |
> > > +                          EXTENT_FLAG_COMPRESS_LZO |
> > > +                          EXTENT_FLAG_COMPRESS_ZSTD)) != 0;
> >
> > As a minor optimizations, you could add another bit flag when any of the
> > zlib/lzo/std is set and test just that.
> 
> How is that an optimization? The compiler ORs those compression flags
> at compile time, it would be equivalent.

Right, it's not the separate test_bit() anymore that would require the
'lock' prefix, it's indeed one constant in one instruction.

Re: [PATCH 00/11] btrfs: some cleanups and optimizations for extent maps

[David Sterba]

On Mon, Dec 04, 2023 at 04:20:22PM +0000, fdmanana@kernel.org wrote:
> From: Filipe Manana <fdmanana@suse.com>
> 
> These do some cleanups around extent maps and their tests, as well as
> some optimizations. These are part of a larger work around extent maps,
> but as they are fairly independent and the remainder will take a longer
> while, sending these out separately. More details on the change logs.
> 
> Filipe Manana (11):
>   btrfs: assert extent map is not in a list when setting it up
>   btrfs: tests: fix error messages for test case 4 of extent map tests
>   btrfs: tests: do not ignore NULL extent maps for extent maps tests
>   btrfs: tests: print all values as decimal in messages for extent map tests
>   btrfs: unexport add_extent_mapping()
>   btrfs: remove redundant value assignment at btrfs_add_extent_mapping()
>   btrfs: log messages at unpin_extent_range() during unexpected cases
>   btrfs: avoid useless rbtree iterations when attempting to merge extent map
>   btrfs: make extent_map_end() argument const
>   btrfs: refactor mergable_maps() for more readability
>   btrfs: use the flags of an extent map to identify the compression type

Added to misc-next, thanks.