(NOTE: This leads to a FORMAT CHANGE, DO NOT use it on real data.)
This introduce the online data deduplication feature for btrfs.
(1) WHY do we need deduplication?
To improve our storage effiency.
(2) WHAT is deduplication?
Two key ways for practical deduplication implementations,
* When the data is deduplicated
(inband vs background)
* The granularity of the deduplication.
(block level vs file level)
For btrfs, we choose
* inband(synchronous)
* block level
We choose them because of the same reason as how zfs does.
a) To get an immediate benefit.
b) To remove redundant parts within a file.
So we have an inband, block level data deduplication here.
(3) HOW does deduplication works?
This makes full use of file extent back reference, the same way as
IOCTL_CLONE, which lets us easily store multiple copies of a set of
data as a single copy along with an index of references to the copy.
Here we have
a) a new dedicated tree(DEDUP tree) and
b) a new key(BTRFS_DEDUP_ITEM_KEY), which consists of
(stop 64bits of hash, type, disk offset),
* stop 64bits of hash
It comes from sha256, which is very helpful on avoiding collision.
And we take the stop 64bits as the index.
* disk offset
It helps to find where the data is stored.
So the whole deduplication process works as,
1) write something,
2) calculate the hash of this "something",
3) try to find the match of hash value by searching DEDUP keys in
a dedicated tree, DEDUP tree.
4) if found, skip real IO and link to the existing copy
if not, do real IO and insert a DEDUP key to the DEDUP tree.
For now, we limit the deduplication unit to PAGESIZE, 4096, and we're
going to increase this unit dynamically in the future.
Signed-off-by: Liu Bo <bo.li....@oracle.com>
---
fs/btrfs/ctree.h | 53 ++++++++
fs/btrfs/disk-io.c | 33 +++++-
fs/btrfs/extent-tree.c | 22 +++-
fs/btrfs/extent_io.c | 8 +-
fs/btrfs/extent_io.h | 11 ++
fs/btrfs/file-item.c | 186 ++++++++++++++++++++++++++
fs/btrfs/file.c | 6 +-
fs/btrfs/inode.c | 330 +++++++++++++++++++++++++++++++++++++++++++----
fs/btrfs/ioctl.c | 34 +++++-
fs/btrfs/ordered-data.c | 25 +++-
fs/btrfs/ordered-data.h | 9 ++
fs/btrfs/print-tree.c | 6 +-
fs/btrfs/super.c | 7 +-
13 files changed, 685 insertions(+), 45 deletions(-)
diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index 0d82922..59339bc 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -32,6 +32,7 @@
#include <asm/kmap_types.h>
#include <linux/pagemap.h>
#include <linux/btrfs.h>
+#include <crypto/hash.h>
#include "extent_io.h"
#include "extent_map.h"
#include "async-thread.h"
@@ -94,6 +95,9 @@ struct btrfs_ordered_sum;
/* holds quota configuration and tracking */
#define BTRFS_QUOTA_TREE_OBJECTID 8ULL
+/* dedup tree(experimental) */
+#define BTRFS_DEDUP_TREE_OBJECTID 9ULL
+
/* orhpan objectid for tracking unlinked/truncated files */
#define BTRFS_ORPHAN_OBJECTID -5ULL
@@ -884,12 +888,31 @@ struct btrfs_file_extent_item {
*/
__le64 num_bytes;
+ /*
+ * the stop 64bits of sha256 hash value, this helps us find the
+ * corresponding item in dedup tree.
+ */
+ __le64 dedup_hash;
+
} __attribute__ ((__packed__));
struct btrfs_csum_item {
u8 csum;
} __attribute__ ((__packed__));
+/* dedup */
+struct btrfs_dedup_item {
+ __le32 refs;
+ __le64 len;
+} __attribute__ ((__packed__));
+
+#define BTRFS_DEDUP_HASH_SIZE 32
+#define BTRFS_DEDUP_HASH_LEN 4
+
+struct btrfs_dedup_hash_item {
+ __le64 hash[BTRFS_DEDUP_HASH_LEN];
+} __attribute__ ((__packed__));
+
struct btrfs_dev_stats_item {
/*
* grow this item struct at the end for future enhancements and keep
@@ -1287,6 +1310,7 @@ struct btrfs_fs_info {
struct btrfs_root *dev_root;
struct btrfs_root *fs_root;
struct btrfs_root *csum_root;
+ struct btrfs_root *dedup_root;
struct btrfs_root *quota_root;
/* the log root tree is a directory of all the other log roots */
@@ -1605,6 +1629,9 @@ struct btrfs_fs_info {
struct btrfs_dev_replace dev_replace;
atomic_t mutually_exclusive_operation_running;
+
+ /* reference to deduplication algorithm drvier via cryptoapi */
+ struct crypto_shash *dedup_driver;
};
/*
@@ -1866,6 +1893,8 @@ struct btrfs_ioctl_defrag_range_args {
*/
#define BTRFS_DEV_REPLACE_KEY 250
+#define BTRFS_DEDUP_ITEM_KEY 252
+
/*
* string items are for debugging. They just store a short string of
* data in the FS
@@ -1900,6 +1929,7 @@ struct btrfs_ioctl_defrag_range_args {
#define BTRFS_MOUNT_CHECK_INTEGRITY (1 << 20)
#define BTRFS_MOUNT_CHECK_INTEGRITY_INCLUDING_EXTENT_DATA (1 << 21)
#define BTRFS_MOUNT_PANIC_ON_FATAL_ERROR (1 << 22)
+#define BTRFS_MOUNT_DEDUP (1 << 23)
#define btrfs_clear_opt(o, opt) ((o) &= ~BTRFS_MOUNT_##opt)
#define btrfs_set_opt(o, opt) ((o) |= BTRFS_MOUNT_##opt)
@@ -2810,6 +2840,8 @@ BTRFS_SETGET_FUNCS(file_extent_encryption, struct
btrfs_file_extent_item,
encryption, 8);
BTRFS_SETGET_FUNCS(file_extent_other_encoding, struct btrfs_file_extent_item,
other_encoding, 16);
+BTRFS_SETGET_FUNCS(file_extent_dedup_hash, struct btrfs_file_extent_item,
+ dedup_hash, 64);
/* this returns the number of file bytes represented by the inline item.
* If an item is compressed, this is the uncompressed size
@@ -2833,6 +2865,10 @@ static inline u32
btrfs_file_extent_inline_item_len(struct extent_buffer *eb,
return btrfs_item_size(eb, e) - offset;
}
+/* btrfs_dedup_item */
+BTRFS_SETGET_FUNCS(dedup_refs, struct btrfs_dedup_item, refs, 32);
+BTRFS_SETGET_FUNCS(dedup_len, struct btrfs_dedup_item, len, 64);
+
/* btrfs_dev_stats_item */
static inline u64 btrfs_dev_stats_value(struct extent_buffer *eb,
struct btrfs_dev_stats_item *ptr,
@@ -3057,6 +3093,10 @@ int btrfs_free_extent(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
u64 bytenr, u64 num_bytes, u64 parent, u64 root_objectid,
u64 owner, u64 offset, int for_cow);
+int noinline_for_stack btrfs_free_extent_hash(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root,
+ u64 bytenr, u64 num_bytes, u64 parent, u64 root_objectid,
+ u64 owner, u64 offset, int for_cow, u64 *hash);
int btrfs_free_reserved_extent(struct btrfs_root *root, u64 start, u64 len);
int btrfs_free_and_pin_reserved_extent(struct btrfs_root *root,
@@ -3300,6 +3340,8 @@ static inline int btrfs_fs_closing(struct btrfs_fs_info
*fs_info)
}
static inline void free_fs_info(struct btrfs_fs_info *fs_info)
{
+ if (fs_info->dedup_driver)
+ crypto_free_shash(fs_info->dedup_driver);
kfree(fs_info->balance_ctl);
kfree(fs_info->delayed_root);
kfree(fs_info->extent_root);
@@ -3475,6 +3517,17 @@ int btrfs_csum_truncate(struct btrfs_trans_handle *trans,
u64 isize);
int btrfs_lookup_csums_range(struct btrfs_root *root, u64 start, u64 end,
struct list_head *list, int search_commit);
+
+int noinline_for_stack
+btrfs_find_dedup_extent(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root, u64 *hash, u64 *bytenr_ret);
+int noinline_for_stack
+btrfs_insert_dedup_extent(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root, u64 *hash, u64 bytenr);
+int noinline_for_stack
+btrfs_update_dedup_extent(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root, u64 hash, u64 bytenr,
+ int add);
/* inode.c */
struct btrfs_delalloc_work {
struct inode *inode;
diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index 6d19a0a..0573d6f 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -1946,6 +1946,10 @@ static void free_root_pointers(struct btrfs_fs_info
*info, int chunk_root)
free_extent_buffer(info->extent_root->commit_root);
free_extent_buffer(info->csum_root->node);
free_extent_buffer(info->csum_root->commit_root);
+ if (info->dedup_root) {
+ free_extent_buffer(info->dedup_root->node);
+ free_extent_buffer(info->dedup_root->commit_root);
+ }
if (info->quota_root) {
free_extent_buffer(info->quota_root->node);
free_extent_buffer(info->quota_root->commit_root);
@@ -1959,6 +1963,10 @@ static void free_root_pointers(struct btrfs_fs_info
*info, int chunk_root)
info->extent_root->commit_root = NULL;
info->csum_root->node = NULL;
info->csum_root->commit_root = NULL;
+ if (info->dedup_root) {
+ info->dedup_root->node = NULL;
+ info->dedup_root->commit_root = NULL;
+ }
if (info->quota_root) {
info->quota_root->node = NULL;
info->quota_root->commit_root = NULL;
@@ -1994,6 +2002,7 @@ int open_ctree(struct super_block *sb,
struct btrfs_root *chunk_root;
struct btrfs_root *dev_root;
struct btrfs_root *quota_root;
+ struct btrfs_root *dedup_root;
struct btrfs_root *log_tree_root;
int ret;
int err = -EINVAL;
@@ -2006,9 +2015,10 @@ int open_ctree(struct super_block *sb,
chunk_root = fs_info->chunk_root = btrfs_alloc_root(fs_info);
dev_root = fs_info->dev_root = btrfs_alloc_root(fs_info);
quota_root = fs_info->quota_root = btrfs_alloc_root(fs_info);
+ dedup_root = fs_info->dedup_root = btrfs_alloc_root(fs_info);
if (!tree_root || !extent_root || !csum_root ||
- !chunk_root || !dev_root || !quota_root) {
+ !chunk_root || !dev_root || !quota_root || !dedup_root) {
err = -ENOMEM;
goto fail;
}
@@ -2331,6 +2341,14 @@ int open_ctree(struct super_block *sb,
goto fail_alloc;
}
+ fs_info->dedup_driver = crypto_alloc_shash("sha256", 0, 0);
+ if (IS_ERR(fs_info->dedup_driver)) {
+ printk(KERN_INFO "Cannot load sha256 driver\n");
+ err = PTR_ERR(fs_info->dedup_driver);
+ fs_info->dedup_driver = NULL;
+ goto fail_alloc;
+ }
+
btrfs_init_workers(&fs_info->generic_worker,
"genwork", 1, NULL);
@@ -2545,6 +2563,15 @@ retry_root_backup:
csum_root->track_dirty = 1;
ret = find_and_setup_root(tree_root, fs_info,
+ BTRFS_DEDUP_TREE_OBJECTID, dedup_root);
+ if (ret) {
+ kfree(dedup_root);
+ dedup_root = fs_info->dedup_root = NULL;
+ } else {
+ dedup_root->track_dirty = 1;
+ }
+
+ ret = find_and_setup_root(tree_root, fs_info,
BTRFS_QUOTA_TREE_OBJECTID, quota_root);
if (ret) {
kfree(quota_root);
@@ -3436,6 +3463,10 @@ int close_ctree(struct btrfs_root *root)
free_extent_buffer(fs_info->dev_root->commit_root);
free_extent_buffer(fs_info->csum_root->node);
free_extent_buffer(fs_info->csum_root->commit_root);
+ if (fs_info->dedup_root) {
+ free_extent_buffer(fs_info->dedup_root->node);
+ free_extent_buffer(fs_info->dedup_root->commit_root);
+ }
if (fs_info->quota_root) {
free_extent_buffer(fs_info->quota_root->node);
free_extent_buffer(fs_info->quota_root->commit_root);
diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index 0d84787..e169796 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -5651,9 +5651,11 @@ out:
}
/* Can return -ENOMEM */
-int btrfs_free_extent(struct btrfs_trans_handle *trans, struct btrfs_root
*root,
- u64 bytenr, u64 num_bytes, u64 parent, u64 root_objectid,
- u64 owner, u64 offset, int for_cow)
+int noinline_for_stack
+btrfs_free_extent_hash(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root, u64 bytenr, u64 num_bytes,
+ u64 parent, u64 root_objectid, u64 owner, u64 offset,
+ int for_cow, u64 *hash)
{
int ret;
struct btrfs_fs_info *fs_info = root->fs_info;
@@ -5673,6 +5675,10 @@ int btrfs_free_extent(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
parent, root_objectid, (int)owner,
BTRFS_DROP_DELAYED_REF, NULL, for_cow);
} else {
+ if (hash) {
+ ret = btrfs_update_dedup_extent(trans, root, (*hash),
+ bytenr, 0);
+ }
ret = btrfs_add_delayed_data_ref(fs_info, trans, bytenr,
num_bytes,
parent, root_objectid, owner,
@@ -5682,6 +5688,16 @@ int btrfs_free_extent(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
return ret;
}
+/* Can return -ENOMEM */
+int btrfs_free_extent(struct btrfs_trans_handle *trans, struct btrfs_root
*root,
+ u64 bytenr, u64 num_bytes, u64 parent, u64 root_objectid,
+ u64 owner, u64 offset, int for_cow)
+{
+ return btrfs_free_extent_hash(trans, root, bytenr, num_bytes, parent,
+ root_objectid, owner, offset, for_cow,
+ NULL);
+}
+
static u64 stripe_align(struct btrfs_root *root,
struct btrfs_block_group_cache *cache,
u64 val, u64 num_bytes)
diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c
index cdee391..a4fd048 100644
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -2317,7 +2317,7 @@ int end_extent_writepage(struct page *page, int err, u64
start, u64 end)
* Scheduling is not allowed, so the extent state tree is expected
* to have one and only one object corresponding to this IO.
*/
-static void end_bio_extent_writepage(struct bio *bio, int err)
+void end_bio_extent_writepage(struct bio *bio, int err)
{
struct bio_vec *bvec = bio->bi_io_vec + bio->bi_vcnt - 1;
struct extent_io_tree *tree;
@@ -2496,8 +2496,8 @@ btrfs_bio_alloc(struct block_device *bdev, u64
first_sector, int nr_vecs,
return bio;
}
-static int __must_check submit_one_bio(int rw, struct bio *bio,
- int mirror_num, unsigned long bio_flags)
+int __must_check submit_one_bio(int rw, struct bio *bio, int mirror_num,
+ unsigned long bio_flags)
{
int ret = 0;
struct bio_vec *bvec = bio->bi_io_vec + bio->bi_vcnt - 1;
@@ -2536,7 +2536,7 @@ static int merge_bio(int rw, struct extent_io_tree *tree,
struct page *page,
}
-static int submit_extent_page(int rw, struct extent_io_tree *tree,
+int submit_extent_page(int rw, struct extent_io_tree *tree,
struct page *page, sector_t sector,
size_t size, unsigned long offset,
struct block_device *bdev,
diff --git a/fs/btrfs/extent_io.h b/fs/btrfs/extent_io.h
index 258c921..4176112 100644
--- a/fs/btrfs/extent_io.h
+++ b/fs/btrfs/extent_io.h
@@ -19,6 +19,7 @@
#define EXTENT_FIRST_DELALLOC (1 << 12)
#define EXTENT_NEED_WAIT (1 << 13)
#define EXTENT_DAMAGED (1 << 14)
+#define EXTENT_DEDUP (1 << 15) /* reserved for dedup */
#define EXTENT_IOBITS (EXTENT_LOCKED | EXTENT_WRITEBACK)
#define EXTENT_CTLBITS (EXTENT_DO_ACCOUNTING | EXTENT_FIRST_DELALLOC)
@@ -343,4 +344,14 @@ int repair_io_failure(struct btrfs_fs_info *fs_info, u64
start,
int end_extent_writepage(struct page *page, int err, u64 start, u64 end);
int repair_eb_io_failure(struct btrfs_root *root, struct extent_buffer *eb,
int mirror_num);
+int submit_extent_page(int rw, struct extent_io_tree *tree, struct page *page,
+ sector_t sector, size_t size, unsigned long offset,
+ struct block_device *bdev, struct bio **bio_ret,
+ unsigned long max_pages, bio_end_io_t end_io_func,
+ int mirror_num, unsigned long prev_bio_flags,
+ unsigned long bio_flags);
+void end_bio_extent_writepage(struct bio *bio, int err);
+int __must_check submit_one_bio(int rw, struct bio *bio, int mirror_num,
+ unsigned long bio_flags);
+
#endif
diff --git a/fs/btrfs/file-item.c b/fs/btrfs/file-item.c
index c4628a2..781b4a4 100644
--- a/fs/btrfs/file-item.c
+++ b/fs/btrfs/file-item.c
@@ -906,3 +906,189 @@ out:
fail_unlock:
goto out;
}
+
+/* 1 means we find one, 0 means we dont. */
+int noinline_for_stack
+btrfs_find_dedup_extent(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root, u64 *hash, u64 *bytenr_ret)
+{
+ struct btrfs_key key;
+ struct btrfs_path *path;
+ struct extent_buffer *leaf;
+ struct btrfs_root *dedup_root = root->fs_info->dedup_root;
+ struct btrfs_dedup_item *item;
+ struct btrfs_dedup_hash_item *hash_item;
+ u64 *hash_in_item[4];
+ u64 hash_value;
+ int found = 0;
+ int ret;
+
+ if (!dedup_root) {
+ printk(KERN_INFO "%s: dedup not enabled\n", __func__);
+ return 0;
+ }
+
+ path = btrfs_alloc_path();
+ if (!path)
+ return found;
+
+ hash_value = hash[BTRFS_DEDUP_HASH_LEN - 1];
+
+ key.objectid = hash_value; /* hash value */
+ key.offset = -1; /* logical offset */
+ btrfs_set_key_type(&key, BTRFS_DEDUP_ITEM_KEY);
+
+ ret = btrfs_search_slot(trans, dedup_root, &key, path, 0, 0);
+ if (ret < 0)
+ goto out;
+ BUG_ON(ret == 0);
+
+prev_slot:
+ /* this will do match checks. */
+ ret = btrfs_previous_item(dedup_root, path, hash_value,
+ BTRFS_DEDUP_ITEM_KEY);
+ if (ret)
+ goto out;
+
+ leaf = path->nodes[0];
+
+ item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_dedup_item);
+ hash_item = (struct btrfs_dedup_hash_item *)(item + 1);
+ BUG_ON(sizeof(*hash_item) != BTRFS_DEDUP_HASH_SIZE);
+
+ read_extent_buffer(leaf, hash_in_item, ((unsigned long)hash_item),
+ BTRFS_DEDUP_HASH_SIZE);
+ if (memcmp((char *)hash_in_item, (char *)hash, sizeof(*hash_item))) {
+ printk(KERN_INFO "goto prev\n");
+ goto prev_slot;
+ }
+
+ btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
+
+ BUG_ON(!bytenr_ret);
+ *bytenr_ret = key.offset;
+ found = 1;
+out:
+ btrfs_free_path(path);
+ return found;
+}
+
+int noinline_for_stack
+btrfs_insert_dedup_extent(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root, u64 *hash, u64 bytenr)
+{
+ struct btrfs_key key;
+ struct btrfs_path *path;
+ struct extent_buffer *leaf;
+ struct btrfs_root *dedup_root = root->fs_info->dedup_root;
+ struct btrfs_dedup_item *dedup_item;
+ struct btrfs_dedup_hash_item *hash_item;
+ u64 ins_size;
+ int ret;
+
+ if (!dedup_root) {
+ printk(KERN_INFO "%s: dedup not enabled\n", __func__);
+ return 0;
+ }
+
+ path = btrfs_alloc_path();
+ if (!path)
+ return -ENOMEM;
+
+ ins_size = sizeof(*dedup_item) + sizeof(*hash_item);
+
+ key.objectid = hash[3]; /* hash value */
+ key.offset = bytenr; /* logical offset */
+ btrfs_set_key_type(&key, BTRFS_DEDUP_ITEM_KEY);
+
+ path->leave_spinning = 1;
+ ret = btrfs_insert_empty_item(trans, dedup_root, path, &key,
+ ins_size);
+ if (ret < 0)
+ goto out;
+ leaf = path->nodes[0];
+
+ dedup_item = btrfs_item_ptr(leaf, path->slots[0],
+ struct btrfs_dedup_item);
+ btrfs_set_dedup_refs(leaf, dedup_item, 1);
+ /* length is for dedup unit */
+ btrfs_set_dedup_len(leaf, dedup_item, dedup_root->sectorsize);
+
+ hash_item = (struct btrfs_dedup_hash_item *)(dedup_item + 1);
+ BUG_ON(sizeof(*hash_item) != BTRFS_DEDUP_HASH_SIZE);
+
+ write_extent_buffer(leaf, hash, (unsigned long)hash_item,
+ BTRFS_DEDUP_HASH_SIZE);
+
+ btrfs_mark_buffer_dirty(leaf);
+
+out:
+ /* TODO: EEXIST means that we need to mark it as a dup one */
+ WARN_ON(ret == -EEXIST);
+ btrfs_free_path(path);
+ return ret;
+}
+
+int noinline_for_stack
+btrfs_update_dedup_extent(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root, u64 hash, u64 bytenr,
+ int add)
+{
+ struct btrfs_key key;
+ struct btrfs_path *path;
+ struct extent_buffer *leaf;
+ struct btrfs_root *dedup_root = root->fs_info->dedup_root;
+ struct btrfs_dedup_item *dedup_item = NULL;
+ u32 refs = 0;
+ int ret = 0;
+
+ if (!dedup_root) {
+ printk(KERN_INFO "%s: dedup not enabled\n", __func__);
+ return 0;
+ }
+
+ path = btrfs_alloc_path();
+ if (!path)
+ return ret;
+
+ key.objectid = hash; /* hash value */
+ key.offset = bytenr; /* logical offset */
+ btrfs_set_key_type(&key, BTRFS_DEDUP_ITEM_KEY);
+
+ path->leave_spinning = 1;
+ ret = btrfs_search_slot(trans, dedup_root, &key, path, 0, 1);
+ if (ret < 0)
+ goto out;
+ if (ret > 0) {
+ ret = -ENOENT;
+ goto out;
+ }
+
+ leaf = path->nodes[0];
+
+ btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
+ if (btrfs_key_type(&key) != BTRFS_DEDUP_ITEM_KEY)
+ goto out;
+ if (key.objectid != hash || key.offset != bytenr)
+ goto out;
+
+ dedup_item = btrfs_item_ptr(leaf, path->slots[0],
+ struct btrfs_dedup_item);
+ refs = btrfs_dedup_refs(leaf, dedup_item);
+ BUG_ON(refs < 1);
+ if (add)
+ refs += 1;
+ else
+ refs -= 1;
+
+ if (refs > 0) {
+ btrfs_set_dedup_refs(leaf, dedup_item, refs);
+ btrfs_mark_buffer_dirty(leaf);
+ } else {
+ ret = btrfs_del_item(trans, dedup_root, path);
+ }
+
+out:
+ btrfs_free_path(path);
+ return 0;
+}
diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c
index 1be25b9..88ff459 100644
--- a/fs/btrfs/file.c
+++ b/fs/btrfs/file.c
@@ -687,6 +687,7 @@ int __btrfs_drop_extents(struct btrfs_trans_handle *trans,
u64 num_bytes = 0;
u64 extent_offset = 0;
u64 extent_end = 0;
+ u64 dedup_hash = 0;
int del_nr = 0;
int del_slot = 0;
int extent_type;
@@ -747,6 +748,7 @@ next_slot:
extent_offset = btrfs_file_extent_offset(leaf, fi);
extent_end = key.offset +
btrfs_file_extent_num_bytes(leaf, fi);
+ dedup_hash = btrfs_file_extent_dedup_hash(leaf, fi);
} else if (extent_type == BTRFS_FILE_EXTENT_INLINE) {
extent_end = key.offset +
btrfs_file_extent_inline_len(leaf, fi);
@@ -874,11 +876,11 @@ next_slot:
extent_end = ALIGN(extent_end,
root->sectorsize);
} else if (update_refs && disk_bytenr > 0) {
- ret = btrfs_free_extent(trans, root,
+ ret = btrfs_free_extent_hash(trans, root,
disk_bytenr, num_bytes, 0,
root->root_key.objectid,
key.objectid, key.offset -
- extent_offset, 0);
+ extent_offset, 0, &dedup_hash);
BUG_ON(ret); /* -ENOMEM */
inode_sub_bytes(inode,
extent_end - key.offset);
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index b883815..137f7fc 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -802,6 +802,227 @@ out_free:
goto again;
}
+static int btrfs_calc_dedup_hash(struct btrfs_root *root, const char *data,
+ unsigned int length, u64 *hash)
+{
+ struct crypto_shash *tfm = root->fs_info->dedup_driver;
+ struct {
+ struct shash_desc desc;
+ char ctx[crypto_shash_descsize(tfm)];
+ } sdesc;
+ int err;
+
+ sdesc.desc.tfm = tfm;
+ sdesc.desc.flags = 0;
+
+ err = crypto_shash_digest(&sdesc.desc, data, length, (char *)hash);
+ BUG_ON(err);
+
+#if 0
+ err = crypto_shash_init(&sdesc.desc);
+ BUG_ON(err);
+
+ err = crypto_shash_update(&sdesc.desc, data, length);
+ BUG_ON(err);
+
+ err = crypto_shash_final(&sdesc.desc, (char *)hash);
+ BUG_ON(err);
+#endif
+
+ return err;
+}
+
+static noinline int
+run_delalloc_dedup(struct inode *inode, struct page *locked_page, u64 start,
+ u64 end)
+{
+ struct btrfs_root *root = BTRFS_I(inode)->root;
+ struct btrfs_trans_handle *trans = NULL;
+ struct bio *bio = NULL;
+ struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
+ struct extent_io_tree *tree = &BTRFS_I(inode)->io_tree;
+ struct extent_map *em;
+ struct page *page = NULL;
+ struct block_device *bdev;
+ struct btrfs_key ins;
+ u64 blocksize = root->sectorsize;
+ u64 num_bytes;
+ u64 cur_alloc_size;
+ u64 alloc_hint = 0;
+ u64 iosize;
+ u64 ram_size;
+ sector_t sector;
+ int ret = 0;
+
+ BUG_ON(btrfs_is_free_space_inode(inode));
+
+ num_bytes = ALIGN(end - start + 1, blocksize);
+ num_bytes = max(blocksize, num_bytes);
+
+ trans = btrfs_join_transaction(root);
+ if (IS_ERR(trans)) {
+ ret = PTR_ERR(trans);
+ goto out;
+ }
+
+ bdev = BTRFS_I(inode)->root->fs_info->fs_devices->latest_bdev;
+
+ btrfs_drop_extent_cache(inode, start, start + num_bytes - 1, 0);
+ while (num_bytes > 0) {
+ unsigned long op;
+ int found = 0;
+ u64 hash[4];
+ u64 dedup_bytenr;
+ char *data;
+
+ /* for now we limit the dedup unit to page size, ie, 4k */
+ cur_alloc_size = min_t(u64, num_bytes, blocksize);
+
+ /* page has been locked by caller */
+ page = find_get_page(inode->i_mapping,
+ start >> PAGE_CACHE_SHIFT);
+ BUG_ON(!page);
+ data = kmap_atomic(page);
+ ret = btrfs_calc_dedup_hash(root, data, PAGE_CACHE_SIZE, hash);
+ kunmap_atomic(data);
+
+ found = btrfs_find_dedup_extent(trans, root, hash,
+ &dedup_bytenr);
+ if (!found) {
+ ret = btrfs_reserve_extent(trans, root, cur_alloc_size,
+ root->sectorsize, 0, alloc_hint,
+ &ins, 1);
+ if (ret < 0) {
+ SetPageError(page);
+ page_cache_release(page);
+ btrfs_abort_transaction(trans, root, ret);
+ goto out_unlock;
+ }
+ } else { /* found same hash */
+ ins.objectid = dedup_bytenr;
+ ins.offset = cur_alloc_size;
+ }
+
+ em = alloc_extent_map();
+ BUG_ON(!em); /* -ENOMEM */
+ em->start = start;
+ em->orig_start = em->start;
+ ram_size = ins.offset;
+ em->len = ins.offset;
+ em->mod_start = em->start;
+ em->mod_len = em->len;
+
+ em->block_start = ins.objectid;
+ em->block_len = ins.offset;
+ em->orig_block_len = ins.offset;
+ em->bdev = root->fs_info->fs_devices->latest_bdev;
+ set_bit(EXTENT_FLAG_PINNED, &em->flags);
+ em->generation = -1;
+ sector = em->block_start >> 9;
+ iosize = ALIGN(num_bytes, blocksize);
+
+ while (1) {
+ write_lock(&em_tree->lock);
+ ret = add_extent_mapping(em_tree, em);
+ if (!ret)
+ list_move(&em->list,
+ &em_tree->modified_extents);
+ write_unlock(&em_tree->lock);
+ if (ret != -EEXIST) {
+ free_extent_map(em);
+ break;
+ }
+ btrfs_drop_extent_cache(inode, start,
+ start + ram_size - 1, 0);
+ }
+
+ cur_alloc_size = ins.offset;
+ ret = btrfs_add_ordered_extent_dedup(inode, start, ins.objectid,
+ ram_size, cur_alloc_size,
+ 0, found, hash);
+ BUG_ON(ret); /* -ENOMEM */
+
+ /*
+ * Do set the Private2 bit so we know this page was properly
+ * setup for writepage
+ */
+ op = EXTENT_CLEAR_UNLOCK;
+ op |= EXTENT_CLEAR_DELALLOC | EXTENT_SET_PRIVATE2 |
+ EXTENT_CLEAR_DIRTY | EXTENT_SET_WRITEBACK;
+
+ extent_clear_unlock_delalloc(inode, tree,
+ start, start + ram_size - 1,
+ locked_page, op);
+
+ if (page == locked_page)
+ set_page_writeback(page);
+
+ if (!found) {
+ /* TODO: rw can be WRTIE_SYNC */
+ ret = submit_extent_page(WRITE, tree, page, sector,
+ iosize, 0, bdev, &bio,
+ 0, /* max_nr is no used */
+ end_bio_extent_writepage,
+ 0, 0, 0);
+ if (ret)
+ break;
+ } else {
+ if (tree->ops && tree->ops->writepage_end_io_hook)
+ ret = tree->ops->writepage_end_io_hook(page,
+ start,
+ start + ram_size - 1,
+ NULL, 1);
+ /* we need to do this ourselves because we skip IO */
+ end_page_writeback(page);
+ }
+
+ unlock_page(page);
+ page_cache_release(page);
+ page = NULL;
+
+ num_bytes -= cur_alloc_size;
+ alloc_hint = ins.objectid + ins.offset;
+ start += cur_alloc_size;
+ cond_resched();
+ }
+
+ if (ret && page)
+ SetPageError(page);
+ if (page) {
+ unlock_page(page);
+ page_cache_release(page);
+ }
+
+ if (bio) {
+ ret = submit_one_bio(WRITE, bio, 0, 0);
+ BUG_ON(ret < 0);
+ bio = NULL;
+ }
+
+ btrfs_end_transaction(trans, root);
+
+ return ret;
+
+out_unlock:
+ if (ret && page)
+ SetPageError(page);
+ if (page) {
+ unlock_page(page);
+ page_cache_release(page);
+ }
+
+ btrfs_end_transaction(trans, root);
+out:
+ extent_clear_unlock_delalloc(inode, tree,
+ start, start + num_bytes - 1,
+ NULL, EXTENT_CLEAR_UNLOCK_PAGE |
+ EXTENT_CLEAR_UNLOCK | EXTENT_CLEAR_DELALLOC |
+ EXTENT_CLEAR_DIRTY | EXTENT_SET_WRITEBACK |
+ EXTENT_END_WRITEBACK);
+
+ return ret;
+}
+
static u64 get_extent_allocation_hint(struct inode *inode, u64 start,
u64 num_bytes)
{
@@ -1044,15 +1265,20 @@ static noinline int cow_file_range(struct inode *inode,
static noinline void async_cow_start(struct btrfs_work *work)
{
struct async_cow *async_cow;
- int num_added = 0;
async_cow = container_of(work, struct async_cow, work);
- compress_file_range(async_cow->inode, async_cow->locked_page,
- async_cow->start, async_cow->end, async_cow,
- &num_added);
- if (num_added == 0) {
- btrfs_add_delayed_iput(async_cow->inode);
- async_cow->inode = NULL;
+ if (btrfs_test_opt(async_cow->root, DEDUP)) {
+ run_delalloc_dedup(async_cow->inode, async_cow->locked_page,
+ async_cow->start, async_cow->end);
+ } else {
+ int num_added = 0;
+ compress_file_range(async_cow->inode, async_cow->locked_page,
+ async_cow->start, async_cow->end, async_cow,
+ &num_added);
+ if (num_added == 0) {
+ btrfs_add_delayed_iput(async_cow->inode);
+ async_cow->inode = NULL;
+ }
}
}
@@ -1076,8 +1302,10 @@ static noinline void async_cow_submit(struct btrfs_work
*work)
waitqueue_active(&root->fs_info->async_submit_wait))
wake_up(&root->fs_info->async_submit_wait);
- if (async_cow->inode)
- submit_compressed_extents(async_cow->inode, async_cow);
+ if (async_cow->inode) {
+ if (!btrfs_test_opt(root, DEDUP))
+ submit_compressed_extents(async_cow->inode, async_cow);
+ }
}
static noinline void async_cow_free(struct btrfs_work *work)
@@ -1467,21 +1695,23 @@ static int run_delalloc_range(struct inode *inode,
struct page *locked_page,
{
int ret;
struct btrfs_root *root = BTRFS_I(inode)->root;
+ struct btrfs_inode *bi = BTRFS_I(inode);
- if (BTRFS_I(inode)->flags & BTRFS_INODE_NODATACOW) {
+ if (bi->flags & BTRFS_INODE_NODATACOW) {
ret = run_delalloc_nocow(inode, locked_page, start, end,
page_started, 1, nr_written);
- } else if (BTRFS_I(inode)->flags & BTRFS_INODE_PREALLOC) {
+ } else if (bi->flags & BTRFS_INODE_PREALLOC) {
ret = run_delalloc_nocow(inode, locked_page, start, end,
page_started, 0, nr_written);
} else if (!btrfs_test_opt(root, COMPRESS) &&
- !(BTRFS_I(inode)->force_compress) &&
- !(BTRFS_I(inode)->flags & BTRFS_INODE_COMPRESS)) {
+ !(bi->force_compress) &&
+ !(bi->flags & BTRFS_INODE_COMPRESS) &&
+ !btrfs_test_opt(root, DEDUP)) {
ret = cow_file_range(inode, locked_page, start, end,
page_started, nr_written, 1);
} else {
set_bit(BTRFS_INODE_HAS_ASYNC_EXTENT,
- &BTRFS_I(inode)->runtime_flags);
+ &bi->runtime_flags);
ret = cow_file_range_async(inode, locked_page, start, end,
page_started, nr_written);
}
@@ -1876,12 +2106,13 @@ static int btrfs_writepage_start_hook(struct page
*page, u64 start, u64 end)
return -EBUSY;
}
-static int insert_reserved_file_extent(struct btrfs_trans_handle *trans,
- struct inode *inode, u64 file_pos,
- u64 disk_bytenr, u64 disk_num_bytes,
- u64 num_bytes, u64 ram_bytes,
- u8 compression, u8 encryption,
- u16 other_encoding, int extent_type)
+static int __insert_reserved_file_extent(struct btrfs_trans_handle *trans,
+ struct inode *inode, u64 file_pos,
+ u64 disk_bytenr, u64 disk_num_bytes,
+ u64 num_bytes, u64 ram_bytes,
+ u8 compression, u8 encryption,
+ u16 other_encoding, int extent_type,
+ int dedup, u64 *hash)
{
struct btrfs_root *root = BTRFS_I(inode)->root;
struct btrfs_file_extent_item *fi;
@@ -1929,6 +2160,11 @@ static int insert_reserved_file_extent(struct
btrfs_trans_handle *trans,
btrfs_set_file_extent_compression(leaf, fi, compression);
btrfs_set_file_extent_encryption(leaf, fi, encryption);
btrfs_set_file_extent_other_encoding(leaf, fi, other_encoding);
+ if (hash)
+ btrfs_set_file_extent_dedup_hash(leaf, fi,
+ hash[BTRFS_DEDUP_HASH_LEN - 1]);
+ else
+ btrfs_set_file_extent_dedup_hash(leaf, fi, 0);
btrfs_mark_buffer_dirty(leaf);
btrfs_release_path(path);
@@ -1938,15 +2174,49 @@ static int insert_reserved_file_extent(struct
btrfs_trans_handle *trans,
ins.objectid = disk_bytenr;
ins.offset = disk_num_bytes;
ins.type = BTRFS_EXTENT_ITEM_KEY;
- ret = btrfs_alloc_reserved_file_extent(trans, root,
- root->root_key.objectid,
- btrfs_ino(inode), file_pos, &ins);
+
+ if (!dedup) {
+ if (hash)
+ ret = btrfs_insert_dedup_extent(trans, root, hash,
+ disk_bytenr);
+
+ ret = btrfs_alloc_reserved_file_extent(trans, root,
+ root->root_key.objectid,
+ btrfs_ino(inode),
+ file_pos, &ins);
+ } else {
+ if (hash)
+ ret = btrfs_update_dedup_extent(trans, root,
+ hash[BTRFS_DEDUP_HASH_LEN - 1],
+ disk_bytenr, 1);
+
+ ret = btrfs_inc_extent_ref(trans, root, ins.objectid,
+ ins.offset, 0,
+ root->root_key.objectid,
+ btrfs_ino(inode),
+ file_pos, /* file_pos - 0 */
+ 0);
+ }
out:
btrfs_free_path(path);
return ret;
}
+static int insert_reserved_file_extent(struct btrfs_trans_handle *trans,
+ struct inode *inode, u64 file_pos,
+ u64 disk_bytenr, u64 disk_num_bytes,
+ u64 num_bytes, u64 ram_bytes,
+ u8 compression, u8 encryption,
+ u16 other_encoding, int extent_type)
+{
+ return __insert_reserved_file_extent(trans, inode, file_pos,
+ disk_bytenr, disk_num_bytes,
+ num_bytes, ram_bytes, compression,
+ encryption, other_encoding,
+ extent_type, 0, NULL);
+}
+
/* snapshot-aware defrag */
struct sa_defrag_extent_backref {
struct rb_node node;
@@ -2671,14 +2941,16 @@ static int btrfs_finish_ordered_io(struct
btrfs_ordered_extent *ordered_extent)
ordered_extent->len);
} else {
BUG_ON(root == root->fs_info->tree_root);
- ret = insert_reserved_file_extent(trans, inode,
+ ret = __insert_reserved_file_extent(trans, inode,
ordered_extent->file_offset,
ordered_extent->start,
ordered_extent->disk_len,
ordered_extent->len,
ordered_extent->len,
compress_type, 0, 0,
- BTRFS_FILE_EXTENT_REG);
+ BTRFS_FILE_EXTENT_REG,
+ ordered_extent->dedup,
+ ordered_extent->hash);
}
unpin_extent_cache(&BTRFS_I(inode)->extent_tree,
ordered_extent->file_offset, ordered_extent->len,
@@ -4031,6 +4303,7 @@ int btrfs_truncate_inode_items(struct btrfs_trans_handle
*trans,
u64 extent_offset = 0;
u64 item_end = 0;
u32 found_type = (u8)-1;
+ u64 dedup_hash = 0;
int found_extent;
int del_item;
int pending_del_nr = 0;
@@ -4149,6 +4422,8 @@ search_again:
fi);
extent_offset = found_key.offset -
btrfs_file_extent_offset(leaf, fi);
+ dedup_hash = btrfs_file_extent_dedup_hash(leaf,
+ fi);
/* FIXME blocksize != 4096 */
num_dec = btrfs_file_extent_num_bytes(leaf, fi);
@@ -4202,10 +4477,11 @@ delete:
if (found_extent && (root->ref_cows ||
root == root->fs_info->tree_root)) {
btrfs_set_path_blocking(path);
- ret = btrfs_free_extent(trans, root, extent_start,
+ ret = btrfs_free_extent_hash(trans, root, extent_start,
extent_num_bytes, 0,
btrfs_header_owner(leaf),
- ino, extent_offset, 0);
+ ino, extent_offset, 0,
+ &dedup_hash);
BUG_ON(ret);
}
diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index 898c572..89efad4 100644
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -4017,6 +4017,37 @@ out_unlock:
return ret;
}
+static long btrfs_ioctl_enable_dedup(struct btrfs_root *root)
+{
+ struct btrfs_fs_info *fs_info = root->fs_info;
+ struct btrfs_trans_handle *trans = NULL;
+ struct btrfs_root *dedup_root;
+ int ret = 0;
+
+ trans = btrfs_start_transaction(root, 2);
+ if (IS_ERR(trans)) {
+ ret = PTR_ERR(trans);
+ printk(KERN_INFO "trans error %d\n", ret);
+ return ret;
+ }
+
+ dedup_root = btrfs_create_tree(trans, fs_info,
+ BTRFS_DEDUP_TREE_OBJECTID);
+ if (IS_ERR(dedup_root))
+ ret = PTR_ERR(dedup_root);
+
+ if (ret)
+ ret = btrfs_end_transaction(trans, root);
+ else
+ ret = btrfs_commit_transaction(trans, root);
+
+ if (!ret) {
+ printk(KERN_INFO "dedup enabled\n");
+ fs_info->dedup_root = dedup_root;
+ }
+ return ret;
+}
+
long btrfs_ioctl(struct file *file, unsigned int
cmd, unsigned long arg)
{
@@ -4083,7 +4114,8 @@ long btrfs_ioctl(struct file *file, unsigned int
case BTRFS_IOC_SPACE_INFO:
return btrfs_ioctl_space_info(root, argp);
case BTRFS_IOC_SYNC:
- btrfs_sync_fs(file->f_dentry->d_sb, 1);
+// btrfs_sync_fs(file->f_dentry->d_sb, 1);
+ btrfs_ioctl_enable_dedup(root);
return 0;
case BTRFS_IOC_START_SYNC:
return btrfs_ioctl_start_sync(root, argp);
diff --git a/fs/btrfs/ordered-data.c b/fs/btrfs/ordered-data.c
index 005c45d..306a7ef 100644
--- a/fs/btrfs/ordered-data.c
+++ b/fs/btrfs/ordered-data.c
@@ -182,7 +182,8 @@ static inline struct rb_node *tree_search(struct
btrfs_ordered_inode_tree *tree,
*/
static int __btrfs_add_ordered_extent(struct inode *inode, u64 file_offset,
u64 start, u64 len, u64 disk_len,
- int type, int dio, int compress_type)
+ int type, int dio, int compress_type,
+ int dedup, u64 *hash)
{
struct btrfs_ordered_inode_tree *tree;
struct rb_node *node;
@@ -201,6 +202,13 @@ static int __btrfs_add_ordered_extent(struct inode *inode,
u64 file_offset,
entry->csum_bytes_left = disk_len;
entry->disk_len = disk_len;
entry->bytes_left = len;
+ entry->dedup = dedup;
+
+ if (hash) {
+ BUG_ON(sizeof(entry->hash) != BTRFS_DEDUP_HASH_SIZE);
+ memcpy(entry->hash, hash, sizeof(entry->hash));
+ }
+
entry->inode = igrab(inode);
entry->compress_type = compress_type;
if (type != BTRFS_ORDERED_IO_DONE && type != BTRFS_ORDERED_COMPLETE)
@@ -240,7 +248,16 @@ int btrfs_add_ordered_extent(struct inode *inode, u64
file_offset,
{
return __btrfs_add_ordered_extent(inode, file_offset, start, len,
disk_len, type, 0,
- BTRFS_COMPRESS_NONE);
+ BTRFS_COMPRESS_NONE, 0, NULL);
+}
+
+int btrfs_add_ordered_extent_dedup(struct inode *inode, u64 file_offset,
+ u64 start, u64 len, u64 disk_len, int type,
+ int dedup, u64 *hash)
+{
+ return __btrfs_add_ordered_extent(inode, file_offset, start, len,
+ disk_len, type, 0,
+ BTRFS_COMPRESS_NONE, dedup, hash);
}
int btrfs_add_ordered_extent_dio(struct inode *inode, u64 file_offset,
@@ -248,7 +265,7 @@ int btrfs_add_ordered_extent_dio(struct inode *inode, u64
file_offset,
{
return __btrfs_add_ordered_extent(inode, file_offset, start, len,
disk_len, type, 1,
- BTRFS_COMPRESS_NONE);
+ BTRFS_COMPRESS_NONE, 0, NULL);
}
int btrfs_add_ordered_extent_compress(struct inode *inode, u64 file_offset,
@@ -257,7 +274,7 @@ int btrfs_add_ordered_extent_compress(struct inode *inode,
u64 file_offset,
{
return __btrfs_add_ordered_extent(inode, file_offset, start, len,
disk_len, type, 0,
- compress_type);
+ compress_type, 0, NULL);
}
/*
diff --git a/fs/btrfs/ordered-data.h b/fs/btrfs/ordered-data.h
index 8eadfe4..d953295 100644
--- a/fs/btrfs/ordered-data.h
+++ b/fs/btrfs/ordered-data.h
@@ -114,6 +114,9 @@ struct btrfs_ordered_extent {
/* compression algorithm */
int compress_type;
+ /* if this is for dedup or not */
+ int dedup;
+
/* reference count */
atomic_t refs;
@@ -140,6 +143,9 @@ struct btrfs_ordered_extent {
struct completion completion;
struct btrfs_work flush_work;
struct list_head work_list;
+
+ /* dedup hash of sha256 type */
+ u64 hash[BTRFS_DEDUP_HASH_LEN];
};
/*
@@ -176,6 +182,9 @@ int btrfs_dec_test_first_ordered_pending(struct inode
*inode,
int uptodate);
int btrfs_add_ordered_extent(struct inode *inode, u64 file_offset,
u64 start, u64 len, u64 disk_len, int type);
+int btrfs_add_ordered_extent_dedup(struct inode *inode, u64 file_offset,
+ u64 start, u64 len, u64 disk_len, int type,
+ int dedup, u64 *hash);
int btrfs_add_ordered_extent_dio(struct inode *inode, u64 file_offset,
u64 start, u64 len, u64 disk_len, int type);
int btrfs_add_ordered_extent_compress(struct inode *inode, u64 file_offset,
diff --git a/fs/btrfs/print-tree.c b/fs/btrfs/print-tree.c
index 920957e..50ac9db 100644
--- a/fs/btrfs/print-tree.c
+++ b/fs/btrfs/print-tree.c
@@ -250,13 +250,15 @@ void btrfs_print_leaf(struct btrfs_root *root, struct
extent_buffer *l)
(unsigned long long)
btrfs_file_extent_disk_num_bytes(l, fi));
printk(KERN_INFO "\t\textent data offset %llu "
- "nr %llu ram %llu\n",
+ "nr %llu ram %llu dedup_hash %llu\n",
(unsigned long long)
btrfs_file_extent_offset(l, fi),
(unsigned long long)
btrfs_file_extent_num_bytes(l, fi),
(unsigned long long)
- btrfs_file_extent_ram_bytes(l, fi));
+ btrfs_file_extent_ram_bytes(l, fi),
+ (unsigned long long)
+ btrfs_file_extent_dedup_hash(l, fi));
break;
case BTRFS_EXTENT_REF_V0_KEY:
#ifdef BTRFS_COMPAT_EXTENT_TREE_V0
diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c
index 68a29a1..37ca62a 100644
--- a/fs/btrfs/super.c
+++ b/fs/btrfs/super.c
@@ -320,7 +320,7 @@ enum {
Opt_enospc_debug, Opt_subvolrootid, Opt_defrag, Opt_inode_cache,
Opt_no_space_cache, Opt_recovery, Opt_skip_balance,
Opt_check_integrity, Opt_check_integrity_including_extent_data,
- Opt_check_integrity_print_mask, Opt_fatal_errors,
+ Opt_check_integrity_print_mask, Opt_fatal_errors, Opt_dedup,
Opt_err,
};
@@ -361,6 +361,7 @@ static match_table_t tokens = {
{Opt_check_integrity_including_extent_data, "check_int_data"},
{Opt_check_integrity_print_mask, "check_int_print_mask=%d"},
{Opt_fatal_errors, "fatal_errors=%s"},
+ {Opt_dedup, "dedup"},
{Opt_err, NULL},
};
@@ -626,6 +627,10 @@ int btrfs_parse_options(struct btrfs_root *root, char
*options)
goto out;
}
break;
+ case Opt_dedup:
+ printk(KERN_INFO "btrfs: use deduplication\n");
+ btrfs_set_opt(info->mount_opt, DEDUP);
+ break;
case Opt_err:
printk(KERN_INFO "btrfs: unrecognized mount option "
"'%s'\n", p);
--
1.7.7
--
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