Merge branch 'for-chris' of git://git.jan-o-sch.net/btrfs-unstable into for-linus
Conflicts:
fs/btrfs/ulist.h
Signed-off-by: Chris Mason <chris.mason@oracle.com>
diff --git a/fs/btrfs/backref.c b/fs/btrfs/backref.c
index bcec067..3f75895 100644
--- a/fs/btrfs/backref.c
+++ b/fs/btrfs/backref.c
@@ -24,22 +24,135 @@
#include "delayed-ref.h"
#include "locking.h"
+struct extent_inode_elem {
+ u64 inum;
+ u64 offset;
+ struct extent_inode_elem *next;
+};
+
+static int check_extent_in_eb(struct btrfs_key *key, struct extent_buffer *eb,
+ struct btrfs_file_extent_item *fi,
+ u64 extent_item_pos,
+ struct extent_inode_elem **eie)
+{
+ u64 data_offset;
+ u64 data_len;
+ struct extent_inode_elem *e;
+
+ data_offset = btrfs_file_extent_offset(eb, fi);
+ data_len = btrfs_file_extent_num_bytes(eb, fi);
+
+ if (extent_item_pos < data_offset ||
+ extent_item_pos >= data_offset + data_len)
+ return 1;
+
+ e = kmalloc(sizeof(*e), GFP_NOFS);
+ if (!e)
+ return -ENOMEM;
+
+ e->next = *eie;
+ e->inum = key->objectid;
+ e->offset = key->offset + (extent_item_pos - data_offset);
+ *eie = e;
+
+ return 0;
+}
+
+static int find_extent_in_eb(struct extent_buffer *eb, u64 wanted_disk_byte,
+ u64 extent_item_pos,
+ struct extent_inode_elem **eie)
+{
+ u64 disk_byte;
+ struct btrfs_key key;
+ struct btrfs_file_extent_item *fi;
+ int slot;
+ int nritems;
+ int extent_type;
+ int ret;
+
+ /*
+ * from the shared data ref, we only have the leaf but we need
+ * the key. thus, we must look into all items and see that we
+ * find one (some) with a reference to our extent item.
+ */
+ nritems = btrfs_header_nritems(eb);
+ for (slot = 0; slot < nritems; ++slot) {
+ btrfs_item_key_to_cpu(eb, &key, slot);
+ if (key.type != BTRFS_EXTENT_DATA_KEY)
+ continue;
+ fi = btrfs_item_ptr(eb, slot, struct btrfs_file_extent_item);
+ extent_type = btrfs_file_extent_type(eb, fi);
+ if (extent_type == BTRFS_FILE_EXTENT_INLINE)
+ continue;
+ /* don't skip BTRFS_FILE_EXTENT_PREALLOC, we can handle that */
+ disk_byte = btrfs_file_extent_disk_bytenr(eb, fi);
+ if (disk_byte != wanted_disk_byte)
+ continue;
+
+ ret = check_extent_in_eb(&key, eb, fi, extent_item_pos, eie);
+ if (ret < 0)
+ return ret;
+ }
+
+ return 0;
+}
+
/*
* this structure records all encountered refs on the way up to the root
*/
struct __prelim_ref {
struct list_head list;
u64 root_id;
- struct btrfs_key key;
+ struct btrfs_key key_for_search;
int level;
int count;
+ struct extent_inode_elem *inode_list;
u64 parent;
u64 wanted_disk_byte;
};
+/*
+ * the rules for all callers of this function are:
+ * - obtaining the parent is the goal
+ * - if you add a key, you must know that it is a correct key
+ * - if you cannot add the parent or a correct key, then we will look into the
+ * block later to set a correct key
+ *
+ * delayed refs
+ * ============
+ * backref type | shared | indirect | shared | indirect
+ * information | tree | tree | data | data
+ * --------------------+--------+----------+--------+----------
+ * parent logical | y | - | - | -
+ * key to resolve | - | y | y | y
+ * tree block logical | - | - | - | -
+ * root for resolving | y | y | y | y
+ *
+ * - column 1: we've the parent -> done
+ * - column 2, 3, 4: we use the key to find the parent
+ *
+ * on disk refs (inline or keyed)
+ * ==============================
+ * backref type | shared | indirect | shared | indirect
+ * information | tree | tree | data | data
+ * --------------------+--------+----------+--------+----------
+ * parent logical | y | - | y | -
+ * key to resolve | - | - | - | y
+ * tree block logical | y | y | y | y
+ * root for resolving | - | y | y | y
+ *
+ * - column 1, 3: we've the parent -> done
+ * - column 2: we take the first key from the block to find the parent
+ * (see __add_missing_keys)
+ * - column 4: we use the key to find the parent
+ *
+ * additional information that's available but not required to find the parent
+ * block might help in merging entries to gain some speed.
+ */
+
static int __add_prelim_ref(struct list_head *head, u64 root_id,
- struct btrfs_key *key, int level, u64 parent,
- u64 wanted_disk_byte, int count)
+ struct btrfs_key *key, int level,
+ u64 parent, u64 wanted_disk_byte, int count)
{
struct __prelim_ref *ref;
@@ -50,10 +163,11 @@
ref->root_id = root_id;
if (key)
- ref->key = *key;
+ ref->key_for_search = *key;
else
- memset(&ref->key, 0, sizeof(ref->key));
+ memset(&ref->key_for_search, 0, sizeof(ref->key_for_search));
+ ref->inode_list = NULL;
ref->level = level;
ref->count = count;
ref->parent = parent;
@@ -64,18 +178,26 @@
}
static int add_all_parents(struct btrfs_root *root, struct btrfs_path *path,
- struct ulist *parents,
- struct extent_buffer *eb, int level,
- u64 wanted_objectid, u64 wanted_disk_byte)
+ struct ulist *parents, int level,
+ struct btrfs_key *key, u64 wanted_disk_byte,
+ const u64 *extent_item_pos)
{
int ret;
- int slot;
+ int slot = path->slots[level];
+ struct extent_buffer *eb = path->nodes[level];
struct btrfs_file_extent_item *fi;
- struct btrfs_key key;
+ struct extent_inode_elem *eie = NULL;
u64 disk_byte;
+ u64 wanted_objectid = key->objectid;
add_parent:
- ret = ulist_add(parents, eb->start, 0, GFP_NOFS);
+ if (level == 0 && extent_item_pos) {
+ fi = btrfs_item_ptr(eb, slot, struct btrfs_file_extent_item);
+ ret = check_extent_in_eb(key, eb, fi, *extent_item_pos, &eie);
+ if (ret < 0)
+ return ret;
+ }
+ ret = ulist_add(parents, eb->start, (unsigned long)eie, GFP_NOFS);
if (ret < 0)
return ret;
@@ -89,6 +211,7 @@
* repeat this until we don't find any additional EXTENT_DATA items.
*/
while (1) {
+ eie = NULL;
ret = btrfs_next_leaf(root, path);
if (ret < 0)
return ret;
@@ -97,9 +220,9 @@
eb = path->nodes[0];
for (slot = 0; slot < btrfs_header_nritems(eb); ++slot) {
- btrfs_item_key_to_cpu(eb, &key, slot);
- if (key.objectid != wanted_objectid ||
- key.type != BTRFS_EXTENT_DATA_KEY)
+ btrfs_item_key_to_cpu(eb, key, slot);
+ if (key->objectid != wanted_objectid ||
+ key->type != BTRFS_EXTENT_DATA_KEY)
return 0;
fi = btrfs_item_ptr(eb, slot,
struct btrfs_file_extent_item);
@@ -118,8 +241,10 @@
*/
static int __resolve_indirect_ref(struct btrfs_fs_info *fs_info,
int search_commit_root,
+ u64 time_seq,
struct __prelim_ref *ref,
- struct ulist *parents)
+ struct ulist *parents,
+ const u64 *extent_item_pos)
{
struct btrfs_path *path;
struct btrfs_root *root;
@@ -152,12 +277,13 @@
goto out;
path->lowest_level = level;
- ret = btrfs_search_slot(NULL, root, &ref->key, path, 0, 0);
+ ret = btrfs_search_old_slot(root, &ref->key_for_search, path, time_seq);
pr_debug("search slot in root %llu (level %d, ref count %d) returned "
"%d for key (%llu %u %llu)\n",
(unsigned long long)ref->root_id, level, ref->count, ret,
- (unsigned long long)ref->key.objectid, ref->key.type,
- (unsigned long long)ref->key.offset);
+ (unsigned long long)ref->key_for_search.objectid,
+ ref->key_for_search.type,
+ (unsigned long long)ref->key_for_search.offset);
if (ret < 0)
goto out;
@@ -179,9 +305,8 @@
btrfs_item_key_to_cpu(eb, &key, path->slots[0]);
}
- /* the last two parameters will only be used for level == 0 */
- ret = add_all_parents(root, path, parents, eb, level, key.objectid,
- ref->wanted_disk_byte);
+ ret = add_all_parents(root, path, parents, level, &key,
+ ref->wanted_disk_byte, extent_item_pos);
out:
btrfs_free_path(path);
return ret;
@@ -191,8 +316,9 @@
* resolve all indirect backrefs from the list
*/
static int __resolve_indirect_refs(struct btrfs_fs_info *fs_info,
- int search_commit_root,
- struct list_head *head)
+ int search_commit_root, u64 time_seq,
+ struct list_head *head,
+ const u64 *extent_item_pos)
{
int err;
int ret = 0;
@@ -201,6 +327,7 @@
struct __prelim_ref *new_ref;
struct ulist *parents;
struct ulist_node *node;
+ struct ulist_iterator uiter;
parents = ulist_alloc(GFP_NOFS);
if (!parents)
@@ -217,7 +344,8 @@
if (ref->count == 0)
continue;
err = __resolve_indirect_ref(fs_info, search_commit_root,
- ref, parents);
+ time_seq, ref, parents,
+ extent_item_pos);
if (err) {
if (ret == 0)
ret = err;
@@ -225,11 +353,14 @@
}
/* we put the first parent into the ref at hand */
- node = ulist_next(parents, NULL);
+ ULIST_ITER_INIT(&uiter);
+ node = ulist_next(parents, &uiter);
ref->parent = node ? node->val : 0;
+ ref->inode_list =
+ node ? (struct extent_inode_elem *)node->aux : 0;
/* additional parents require new refs being added here */
- while ((node = ulist_next(parents, node))) {
+ while ((node = ulist_next(parents, &uiter))) {
new_ref = kmalloc(sizeof(*new_ref), GFP_NOFS);
if (!new_ref) {
ret = -ENOMEM;
@@ -237,6 +368,8 @@
}
memcpy(new_ref, ref, sizeof(*ref));
new_ref->parent = node->val;
+ new_ref->inode_list =
+ (struct extent_inode_elem *)node->aux;
list_add(&new_ref->list, &ref->list);
}
ulist_reinit(parents);
@@ -246,10 +379,65 @@
return ret;
}
+static inline int ref_for_same_block(struct __prelim_ref *ref1,
+ struct __prelim_ref *ref2)
+{
+ if (ref1->level != ref2->level)
+ return 0;
+ if (ref1->root_id != ref2->root_id)
+ return 0;
+ if (ref1->key_for_search.type != ref2->key_for_search.type)
+ return 0;
+ if (ref1->key_for_search.objectid != ref2->key_for_search.objectid)
+ return 0;
+ if (ref1->key_for_search.offset != ref2->key_for_search.offset)
+ return 0;
+ if (ref1->parent != ref2->parent)
+ return 0;
+
+ return 1;
+}
+
+/*
+ * read tree blocks and add keys where required.
+ */
+static int __add_missing_keys(struct btrfs_fs_info *fs_info,
+ struct list_head *head)
+{
+ struct list_head *pos;
+ struct extent_buffer *eb;
+
+ list_for_each(pos, head) {
+ struct __prelim_ref *ref;
+ ref = list_entry(pos, struct __prelim_ref, list);
+
+ if (ref->parent)
+ continue;
+ if (ref->key_for_search.type)
+ continue;
+ BUG_ON(!ref->wanted_disk_byte);
+ eb = read_tree_block(fs_info->tree_root, ref->wanted_disk_byte,
+ fs_info->tree_root->leafsize, 0);
+ BUG_ON(!eb);
+ btrfs_tree_read_lock(eb);
+ if (btrfs_header_level(eb) == 0)
+ btrfs_item_key_to_cpu(eb, &ref->key_for_search, 0);
+ else
+ btrfs_node_key_to_cpu(eb, &ref->key_for_search, 0);
+ btrfs_tree_read_unlock(eb);
+ free_extent_buffer(eb);
+ }
+ return 0;
+}
+
/*
* merge two lists of backrefs and adjust counts accordingly
*
* mode = 1: merge identical keys, if key is set
+ * FIXME: if we add more keys in __add_prelim_ref, we can merge more here.
+ * additionally, we could even add a key range for the blocks we
+ * looked into to merge even more (-> replace unresolved refs by those
+ * having a parent).
* mode = 2: merge identical parents
*/
static int __merge_refs(struct list_head *head, int mode)
@@ -263,20 +451,21 @@
ref1 = list_entry(pos1, struct __prelim_ref, list);
- if (mode == 1 && ref1->key.type == 0)
- continue;
for (pos2 = pos1->next, n2 = pos2->next; pos2 != head;
pos2 = n2, n2 = pos2->next) {
struct __prelim_ref *ref2;
+ struct __prelim_ref *xchg;
ref2 = list_entry(pos2, struct __prelim_ref, list);
if (mode == 1) {
- if (memcmp(&ref1->key, &ref2->key,
- sizeof(ref1->key)) ||
- ref1->level != ref2->level ||
- ref1->root_id != ref2->root_id)
+ if (!ref_for_same_block(ref1, ref2))
continue;
+ if (!ref1->parent && ref2->parent) {
+ xchg = ref1;
+ ref1 = ref2;
+ ref2 = xchg;
+ }
ref1->count += ref2->count;
} else {
if (ref1->parent != ref2->parent)
@@ -296,16 +485,17 @@
* smaller or equal that seq to the list
*/
static int __add_delayed_refs(struct btrfs_delayed_ref_head *head, u64 seq,
- struct btrfs_key *info_key,
struct list_head *prefs)
{
struct btrfs_delayed_extent_op *extent_op = head->extent_op;
struct rb_node *n = &head->node.rb_node;
+ struct btrfs_key key;
+ struct btrfs_key op_key = {0};
int sgn;
int ret = 0;
if (extent_op && extent_op->update_key)
- btrfs_disk_key_to_cpu(info_key, &extent_op->key);
+ btrfs_disk_key_to_cpu(&op_key, &extent_op->key);
while ((n = rb_prev(n))) {
struct btrfs_delayed_ref_node *node;
@@ -337,7 +527,7 @@
struct btrfs_delayed_tree_ref *ref;
ref = btrfs_delayed_node_to_tree_ref(node);
- ret = __add_prelim_ref(prefs, ref->root, info_key,
+ ret = __add_prelim_ref(prefs, ref->root, &op_key,
ref->level + 1, 0, node->bytenr,
node->ref_mod * sgn);
break;
@@ -346,7 +536,7 @@
struct btrfs_delayed_tree_ref *ref;
ref = btrfs_delayed_node_to_tree_ref(node);
- ret = __add_prelim_ref(prefs, ref->root, info_key,
+ ret = __add_prelim_ref(prefs, ref->root, NULL,
ref->level + 1, ref->parent,
node->bytenr,
node->ref_mod * sgn);
@@ -354,8 +544,6 @@
}
case BTRFS_EXTENT_DATA_REF_KEY: {
struct btrfs_delayed_data_ref *ref;
- struct btrfs_key key;
-
ref = btrfs_delayed_node_to_data_ref(node);
key.objectid = ref->objectid;
@@ -368,7 +556,6 @@
}
case BTRFS_SHARED_DATA_REF_KEY: {
struct btrfs_delayed_data_ref *ref;
- struct btrfs_key key;
ref = btrfs_delayed_node_to_data_ref(node);
@@ -394,8 +581,7 @@
*/
static int __add_inline_refs(struct btrfs_fs_info *fs_info,
struct btrfs_path *path, u64 bytenr,
- struct btrfs_key *info_key, int *info_level,
- struct list_head *prefs)
+ int *info_level, struct list_head *prefs)
{
int ret = 0;
int slot;
@@ -411,7 +597,7 @@
* enumerate all inline refs
*/
leaf = path->nodes[0];
- slot = path->slots[0] - 1;
+ slot = path->slots[0];
item_size = btrfs_item_size_nr(leaf, slot);
BUG_ON(item_size < sizeof(*ei));
@@ -424,12 +610,9 @@
if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK) {
struct btrfs_tree_block_info *info;
- struct btrfs_disk_key disk_key;
info = (struct btrfs_tree_block_info *)ptr;
*info_level = btrfs_tree_block_level(leaf, info);
- btrfs_tree_block_key(leaf, info, &disk_key);
- btrfs_disk_key_to_cpu(info_key, &disk_key);
ptr += sizeof(struct btrfs_tree_block_info);
BUG_ON(ptr > end);
} else {
@@ -447,7 +630,7 @@
switch (type) {
case BTRFS_SHARED_BLOCK_REF_KEY:
- ret = __add_prelim_ref(prefs, 0, info_key,
+ ret = __add_prelim_ref(prefs, 0, NULL,
*info_level + 1, offset,
bytenr, 1);
break;
@@ -462,8 +645,9 @@
break;
}
case BTRFS_TREE_BLOCK_REF_KEY:
- ret = __add_prelim_ref(prefs, offset, info_key,
- *info_level + 1, 0, bytenr, 1);
+ ret = __add_prelim_ref(prefs, offset, NULL,
+ *info_level + 1, 0,
+ bytenr, 1);
break;
case BTRFS_EXTENT_DATA_REF_KEY: {
struct btrfs_extent_data_ref *dref;
@@ -477,8 +661,8 @@
key.type = BTRFS_EXTENT_DATA_KEY;
key.offset = btrfs_extent_data_ref_offset(leaf, dref);
root = btrfs_extent_data_ref_root(leaf, dref);
- ret = __add_prelim_ref(prefs, root, &key, 0, 0, bytenr,
- count);
+ ret = __add_prelim_ref(prefs, root, &key, 0, 0,
+ bytenr, count);
break;
}
default:
@@ -496,8 +680,7 @@
*/
static int __add_keyed_refs(struct btrfs_fs_info *fs_info,
struct btrfs_path *path, u64 bytenr,
- struct btrfs_key *info_key, int info_level,
- struct list_head *prefs)
+ int info_level, struct list_head *prefs)
{
struct btrfs_root *extent_root = fs_info->extent_root;
int ret;
@@ -527,7 +710,7 @@
switch (key.type) {
case BTRFS_SHARED_BLOCK_REF_KEY:
- ret = __add_prelim_ref(prefs, 0, info_key,
+ ret = __add_prelim_ref(prefs, 0, NULL,
info_level + 1, key.offset,
bytenr, 1);
break;
@@ -543,8 +726,9 @@
break;
}
case BTRFS_TREE_BLOCK_REF_KEY:
- ret = __add_prelim_ref(prefs, key.offset, info_key,
- info_level + 1, 0, bytenr, 1);
+ ret = __add_prelim_ref(prefs, key.offset, NULL,
+ info_level + 1, 0,
+ bytenr, 1);
break;
case BTRFS_EXTENT_DATA_REF_KEY: {
struct btrfs_extent_data_ref *dref;
@@ -560,7 +744,7 @@
key.offset = btrfs_extent_data_ref_offset(leaf, dref);
root = btrfs_extent_data_ref_root(leaf, dref);
ret = __add_prelim_ref(prefs, root, &key, 0, 0,
- bytenr, count);
+ bytenr, count);
break;
}
default:
@@ -582,11 +766,12 @@
*/
static int find_parent_nodes(struct btrfs_trans_handle *trans,
struct btrfs_fs_info *fs_info, u64 bytenr,
- u64 seq, struct ulist *refs, struct ulist *roots)
+ u64 delayed_ref_seq, u64 time_seq,
+ struct ulist *refs, struct ulist *roots,
+ const u64 *extent_item_pos)
{
struct btrfs_key key;
struct btrfs_path *path;
- struct btrfs_key info_key = { 0 };
struct btrfs_delayed_ref_root *delayed_refs = NULL;
struct btrfs_delayed_ref_head *head;
int info_level = 0;
@@ -645,7 +830,7 @@
btrfs_put_delayed_ref(&head->node);
goto again;
}
- ret = __add_delayed_refs(head, seq, &info_key,
+ ret = __add_delayed_refs(head, delayed_ref_seq,
&prefs_delayed);
if (ret) {
spin_unlock(&delayed_refs->lock);
@@ -659,16 +844,17 @@
struct extent_buffer *leaf;
int slot;
+ path->slots[0]--;
leaf = path->nodes[0];
- slot = path->slots[0] - 1;
+ slot = path->slots[0];
btrfs_item_key_to_cpu(leaf, &key, slot);
if (key.objectid == bytenr &&
key.type == BTRFS_EXTENT_ITEM_KEY) {
ret = __add_inline_refs(fs_info, path, bytenr,
- &info_key, &info_level, &prefs);
+ &info_level, &prefs);
if (ret)
goto out;
- ret = __add_keyed_refs(fs_info, path, bytenr, &info_key,
+ ret = __add_keyed_refs(fs_info, path, bytenr,
info_level, &prefs);
if (ret)
goto out;
@@ -676,21 +862,18 @@
}
btrfs_release_path(path);
- /*
- * when adding the delayed refs above, the info_key might not have
- * been known yet. Go over the list and replace the missing keys
- */
- list_for_each_entry(ref, &prefs_delayed, list) {
- if ((ref->key.offset | ref->key.type | ref->key.objectid) == 0)
- memcpy(&ref->key, &info_key, sizeof(ref->key));
- }
list_splice_init(&prefs_delayed, &prefs);
+ ret = __add_missing_keys(fs_info, &prefs);
+ if (ret)
+ goto out;
+
ret = __merge_refs(&prefs, 1);
if (ret)
goto out;
- ret = __resolve_indirect_refs(fs_info, search_commit_root, &prefs);
+ ret = __resolve_indirect_refs(fs_info, search_commit_root, time_seq,
+ &prefs, extent_item_pos);
if (ret)
goto out;
@@ -709,7 +892,33 @@
BUG_ON(ret < 0);
}
if (ref->count && ref->parent) {
- ret = ulist_add(refs, ref->parent, 0, GFP_NOFS);
+ struct extent_inode_elem *eie = NULL;
+ if (extent_item_pos && !ref->inode_list) {
+ u32 bsz;
+ struct extent_buffer *eb;
+ bsz = btrfs_level_size(fs_info->extent_root,
+ info_level);
+ eb = read_tree_block(fs_info->extent_root,
+ ref->parent, bsz, 0);
+ BUG_ON(!eb);
+ ret = find_extent_in_eb(eb, bytenr,
+ *extent_item_pos, &eie);
+ ref->inode_list = eie;
+ free_extent_buffer(eb);
+ }
+ ret = ulist_add_merge(refs, ref->parent,
+ (unsigned long)ref->inode_list,
+ (unsigned long *)&eie, GFP_NOFS);
+ if (!ret && extent_item_pos) {
+ /*
+ * we've recorded that parent, so we must extend
+ * its inode list here
+ */
+ BUG_ON(!eie);
+ while (eie->next)
+ eie = eie->next;
+ eie->next = ref->inode_list;
+ }
BUG_ON(ret < 0);
}
kfree(ref);
@@ -734,6 +943,28 @@
return ret;
}
+static void free_leaf_list(struct ulist *blocks)
+{
+ struct ulist_node *node = NULL;
+ struct extent_inode_elem *eie;
+ struct extent_inode_elem *eie_next;
+ struct ulist_iterator uiter;
+
+ ULIST_ITER_INIT(&uiter);
+ while ((node = ulist_next(blocks, &uiter))) {
+ if (!node->aux)
+ continue;
+ eie = (struct extent_inode_elem *)node->aux;
+ for (; eie; eie = eie_next) {
+ eie_next = eie->next;
+ kfree(eie);
+ }
+ node->aux = 0;
+ }
+
+ ulist_free(blocks);
+}
+
/*
* Finds all leafs with a reference to the specified combination of bytenr and
* offset. key_list_head will point to a list of corresponding keys (caller must
@@ -744,7 +975,9 @@
*/
static int btrfs_find_all_leafs(struct btrfs_trans_handle *trans,
struct btrfs_fs_info *fs_info, u64 bytenr,
- u64 num_bytes, u64 seq, struct ulist **leafs)
+ u64 delayed_ref_seq, u64 time_seq,
+ struct ulist **leafs,
+ const u64 *extent_item_pos)
{
struct ulist *tmp;
int ret;
@@ -758,11 +991,12 @@
return -ENOMEM;
}
- ret = find_parent_nodes(trans, fs_info, bytenr, seq, *leafs, tmp);
+ ret = find_parent_nodes(trans, fs_info, bytenr, delayed_ref_seq,
+ time_seq, *leafs, tmp, extent_item_pos);
ulist_free(tmp);
if (ret < 0 && ret != -ENOENT) {
- ulist_free(*leafs);
+ free_leaf_list(*leafs);
return ret;
}
@@ -784,10 +1018,12 @@
*/
int btrfs_find_all_roots(struct btrfs_trans_handle *trans,
struct btrfs_fs_info *fs_info, u64 bytenr,
- u64 num_bytes, u64 seq, struct ulist **roots)
+ u64 delayed_ref_seq, u64 time_seq,
+ struct ulist **roots)
{
struct ulist *tmp;
struct ulist_node *node = NULL;
+ struct ulist_iterator uiter;
int ret;
tmp = ulist_alloc(GFP_NOFS);
@@ -799,15 +1035,16 @@
return -ENOMEM;
}
+ ULIST_ITER_INIT(&uiter);
while (1) {
- ret = find_parent_nodes(trans, fs_info, bytenr, seq,
- tmp, *roots);
+ ret = find_parent_nodes(trans, fs_info, bytenr, delayed_ref_seq,
+ time_seq, tmp, *roots, NULL);
if (ret < 0 && ret != -ENOENT) {
ulist_free(tmp);
ulist_free(*roots);
return ret;
}
- node = ulist_next(tmp, node);
+ node = ulist_next(tmp, &uiter);
if (!node)
break;
bytenr = node->val;
@@ -1093,67 +1330,25 @@
return 0;
}
-static int iterate_leaf_refs(struct btrfs_fs_info *fs_info, u64 logical,
- u64 orig_extent_item_objectid,
- u64 extent_item_pos, u64 root,
+static int iterate_leaf_refs(struct extent_inode_elem *inode_list,
+ u64 root, u64 extent_item_objectid,
iterate_extent_inodes_t *iterate, void *ctx)
{
- u64 disk_byte;
- struct btrfs_key key;
- struct btrfs_file_extent_item *fi;
- struct extent_buffer *eb;
- int slot;
- int nritems;
+ struct extent_inode_elem *eie;
int ret = 0;
- int extent_type;
- u64 data_offset;
- u64 data_len;
- eb = read_tree_block(fs_info->tree_root, logical,
- fs_info->tree_root->leafsize, 0);
- if (!eb)
- return -EIO;
-
- /*
- * from the shared data ref, we only have the leaf but we need
- * the key. thus, we must look into all items and see that we
- * find one (some) with a reference to our extent item.
- */
- nritems = btrfs_header_nritems(eb);
- for (slot = 0; slot < nritems; ++slot) {
- btrfs_item_key_to_cpu(eb, &key, slot);
- if (key.type != BTRFS_EXTENT_DATA_KEY)
- continue;
- fi = btrfs_item_ptr(eb, slot, struct btrfs_file_extent_item);
- extent_type = btrfs_file_extent_type(eb, fi);
- if (extent_type == BTRFS_FILE_EXTENT_INLINE)
- continue;
- /* don't skip BTRFS_FILE_EXTENT_PREALLOC, we can handle that */
- disk_byte = btrfs_file_extent_disk_bytenr(eb, fi);
- if (disk_byte != orig_extent_item_objectid)
- continue;
-
- data_offset = btrfs_file_extent_offset(eb, fi);
- data_len = btrfs_file_extent_num_bytes(eb, fi);
-
- if (extent_item_pos < data_offset ||
- extent_item_pos >= data_offset + data_len)
- continue;
-
+ for (eie = inode_list; eie; eie = eie->next) {
pr_debug("ref for %llu resolved, key (%llu EXTEND_DATA %llu), "
- "root %llu\n", orig_extent_item_objectid,
- key.objectid, key.offset, root);
- ret = iterate(key.objectid,
- key.offset + (extent_item_pos - data_offset),
- root, ctx);
+ "root %llu\n", extent_item_objectid,
+ eie->inum, eie->offset, root);
+ ret = iterate(eie->inum, eie->offset, root, ctx);
if (ret) {
- pr_debug("stopping iteration because ret=%d\n", ret);
+ pr_debug("stopping iteration for %llu due to ret=%d\n",
+ extent_item_objectid, ret);
break;
}
}
- free_extent_buffer(eb);
-
return ret;
}
@@ -1175,7 +1370,10 @@
struct ulist *roots = NULL;
struct ulist_node *ref_node = NULL;
struct ulist_node *root_node = NULL;
- struct seq_list seq_elem;
+ struct seq_list seq_elem = {};
+ struct seq_list tree_mod_seq_elem = {};
+ struct ulist_iterator ref_uiter;
+ struct ulist_iterator root_uiter;
struct btrfs_delayed_ref_root *delayed_refs = NULL;
pr_debug("resolving all inodes for extent %llu\n",
@@ -1192,34 +1390,41 @@
spin_lock(&delayed_refs->lock);
btrfs_get_delayed_seq(delayed_refs, &seq_elem);
spin_unlock(&delayed_refs->lock);
+ btrfs_get_tree_mod_seq(fs_info, &tree_mod_seq_elem);
}
ret = btrfs_find_all_leafs(trans, fs_info, extent_item_objectid,
- extent_item_pos, seq_elem.seq,
- &refs);
-
+ seq_elem.seq, tree_mod_seq_elem.seq, &refs,
+ &extent_item_pos);
if (ret)
goto out;
- while (!ret && (ref_node = ulist_next(refs, ref_node))) {
- ret = btrfs_find_all_roots(trans, fs_info, ref_node->val, -1,
- seq_elem.seq, &roots);
+ ULIST_ITER_INIT(&ref_uiter);
+ while (!ret && (ref_node = ulist_next(refs, &ref_uiter))) {
+ ret = btrfs_find_all_roots(trans, fs_info, ref_node->val,
+ seq_elem.seq,
+ tree_mod_seq_elem.seq, &roots);
if (ret)
break;
- while (!ret && (root_node = ulist_next(roots, root_node))) {
- pr_debug("root %llu references leaf %llu\n",
- root_node->val, ref_node->val);
- ret = iterate_leaf_refs(fs_info, ref_node->val,
- extent_item_objectid,
- extent_item_pos, root_node->val,
- iterate, ctx);
+ ULIST_ITER_INIT(&root_uiter);
+ while (!ret && (root_node = ulist_next(roots, &root_uiter))) {
+ pr_debug("root %llu references leaf %llu, data list "
+ "%#lx\n", root_node->val, ref_node->val,
+ ref_node->aux);
+ ret = iterate_leaf_refs(
+ (struct extent_inode_elem *)ref_node->aux,
+ root_node->val, extent_item_objectid,
+ iterate, ctx);
}
+ ulist_free(roots);
+ roots = NULL;
}
- ulist_free(refs);
+ free_leaf_list(refs);
ulist_free(roots);
out:
if (!search_commit_root) {
+ btrfs_put_tree_mod_seq(fs_info, &tree_mod_seq_elem);
btrfs_put_delayed_seq(delayed_refs, &seq_elem);
btrfs_end_transaction(trans, fs_info->extent_root);
}
diff --git a/fs/btrfs/backref.h b/fs/btrfs/backref.h
index 57ea2e9..c18d8ac 100644
--- a/fs/btrfs/backref.h
+++ b/fs/btrfs/backref.h
@@ -58,7 +58,8 @@
int btrfs_find_all_roots(struct btrfs_trans_handle *trans,
struct btrfs_fs_info *fs_info, u64 bytenr,
- u64 num_bytes, u64 seq, struct ulist **roots);
+ u64 delayed_ref_seq, u64 time_seq,
+ struct ulist **roots);
struct btrfs_data_container *init_data_container(u32 total_bytes);
struct inode_fs_paths *init_ipath(s32 total_bytes, struct btrfs_root *fs_root,
diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c
index 99fcad6..d7a96cf 100644
--- a/fs/btrfs/ctree.c
+++ b/fs/btrfs/ctree.c
@@ -18,6 +18,7 @@
#include <linux/sched.h>
#include <linux/slab.h>
+#include <linux/rbtree.h>
#include "ctree.h"
#include "disk-io.h"
#include "transaction.h"
@@ -37,7 +38,16 @@
struct extent_buffer *dst_buf,
struct extent_buffer *src_buf);
static void del_ptr(struct btrfs_trans_handle *trans, struct btrfs_root *root,
- struct btrfs_path *path, int level, int slot);
+ struct btrfs_path *path, int level, int slot,
+ int tree_mod_log);
+static void tree_mod_log_free_eb(struct btrfs_fs_info *fs_info,
+ struct extent_buffer *eb);
+struct extent_buffer *read_old_tree_block(struct btrfs_root *root, u64 bytenr,
+ u32 blocksize, u64 parent_transid,
+ u64 time_seq);
+struct extent_buffer *btrfs_find_old_tree_block(struct btrfs_root *root,
+ u64 bytenr, u32 blocksize,
+ u64 time_seq);
struct btrfs_path *btrfs_alloc_path(void)
{
@@ -255,7 +265,7 @@
cow = btrfs_alloc_free_block(trans, root, buf->len, 0,
new_root_objectid, &disk_key, level,
- buf->start, 0, 1);
+ buf->start, 0);
if (IS_ERR(cow))
return PTR_ERR(cow);
@@ -288,6 +298,434 @@
return 0;
}
+enum mod_log_op {
+ MOD_LOG_KEY_REPLACE,
+ MOD_LOG_KEY_ADD,
+ MOD_LOG_KEY_REMOVE,
+ MOD_LOG_KEY_REMOVE_WHILE_FREEING,
+ MOD_LOG_KEY_REMOVE_WHILE_MOVING,
+ MOD_LOG_MOVE_KEYS,
+ MOD_LOG_ROOT_REPLACE,
+};
+
+struct tree_mod_move {
+ int dst_slot;
+ int nr_items;
+};
+
+struct tree_mod_root {
+ u64 logical;
+ u8 level;
+};
+
+struct tree_mod_elem {
+ struct rb_node node;
+ u64 index; /* shifted logical */
+ struct seq_list elem;
+ enum mod_log_op op;
+
+ /* this is used for MOD_LOG_KEY_* and MOD_LOG_MOVE_KEYS operations */
+ int slot;
+
+ /* this is used for MOD_LOG_KEY* and MOD_LOG_ROOT_REPLACE */
+ u64 generation;
+
+ /* those are used for op == MOD_LOG_KEY_{REPLACE,REMOVE} */
+ struct btrfs_disk_key key;
+ u64 blockptr;
+
+ /* this is used for op == MOD_LOG_MOVE_KEYS */
+ struct tree_mod_move move;
+
+ /* this is used for op == MOD_LOG_ROOT_REPLACE */
+ struct tree_mod_root old_root;
+};
+
+static inline void
+__get_tree_mod_seq(struct btrfs_fs_info *fs_info, struct seq_list *elem)
+{
+ elem->seq = atomic_inc_return(&fs_info->tree_mod_seq);
+ list_add_tail(&elem->list, &fs_info->tree_mod_seq_list);
+}
+
+void btrfs_get_tree_mod_seq(struct btrfs_fs_info *fs_info,
+ struct seq_list *elem)
+{
+ elem->flags = 1;
+ spin_lock(&fs_info->tree_mod_seq_lock);
+ __get_tree_mod_seq(fs_info, elem);
+ spin_unlock(&fs_info->tree_mod_seq_lock);
+}
+
+void btrfs_put_tree_mod_seq(struct btrfs_fs_info *fs_info,
+ struct seq_list *elem)
+{
+ struct rb_root *tm_root;
+ struct rb_node *node;
+ struct rb_node *next;
+ struct seq_list *cur_elem;
+ struct tree_mod_elem *tm;
+ u64 min_seq = (u64)-1;
+ u64 seq_putting = elem->seq;
+
+ if (!seq_putting)
+ return;
+
+ BUG_ON(!(elem->flags & 1));
+ spin_lock(&fs_info->tree_mod_seq_lock);
+ list_del(&elem->list);
+
+ list_for_each_entry(cur_elem, &fs_info->tree_mod_seq_list, list) {
+ if ((cur_elem->flags & 1) && cur_elem->seq < min_seq) {
+ if (seq_putting > cur_elem->seq) {
+ /*
+ * blocker with lower sequence number exists, we
+ * cannot remove anything from the log
+ */
+ goto out;
+ }
+ min_seq = cur_elem->seq;
+ }
+ }
+
+ /*
+ * anything that's lower than the lowest existing (read: blocked)
+ * sequence number can be removed from the tree.
+ */
+ write_lock(&fs_info->tree_mod_log_lock);
+ tm_root = &fs_info->tree_mod_log;
+ for (node = rb_first(tm_root); node; node = next) {
+ next = rb_next(node);
+ tm = container_of(node, struct tree_mod_elem, node);
+ if (tm->elem.seq > min_seq)
+ continue;
+ rb_erase(node, tm_root);
+ list_del(&tm->elem.list);
+ kfree(tm);
+ }
+ write_unlock(&fs_info->tree_mod_log_lock);
+out:
+ spin_unlock(&fs_info->tree_mod_seq_lock);
+}
+
+/*
+ * key order of the log:
+ * index -> sequence
+ *
+ * the index is the shifted logical of the *new* root node for root replace
+ * operations, or the shifted logical of the affected block for all other
+ * operations.
+ */
+static noinline int
+__tree_mod_log_insert(struct btrfs_fs_info *fs_info, struct tree_mod_elem *tm)
+{
+ struct rb_root *tm_root;
+ struct rb_node **new;
+ struct rb_node *parent = NULL;
+ struct tree_mod_elem *cur;
+ int ret = 0;
+
+ BUG_ON(!tm || !tm->elem.seq);
+
+ write_lock(&fs_info->tree_mod_log_lock);
+ tm_root = &fs_info->tree_mod_log;
+ new = &tm_root->rb_node;
+ while (*new) {
+ cur = container_of(*new, struct tree_mod_elem, node);
+ parent = *new;
+ if (cur->index < tm->index)
+ new = &((*new)->rb_left);
+ else if (cur->index > tm->index)
+ new = &((*new)->rb_right);
+ else if (cur->elem.seq < tm->elem.seq)
+ new = &((*new)->rb_left);
+ else if (cur->elem.seq > tm->elem.seq)
+ new = &((*new)->rb_right);
+ else {
+ kfree(tm);
+ ret = -EEXIST;
+ goto unlock;
+ }
+ }
+
+ rb_link_node(&tm->node, parent, new);
+ rb_insert_color(&tm->node, tm_root);
+unlock:
+ write_unlock(&fs_info->tree_mod_log_lock);
+ return ret;
+}
+
+static inline int tree_mod_dont_log(struct btrfs_fs_info *fs_info,
+ struct extent_buffer *eb) {
+ smp_mb();
+ if (list_empty(&(fs_info)->tree_mod_seq_list))
+ return 1;
+ if (!eb)
+ return 0;
+ if (btrfs_header_level(eb) == 0)
+ return 1;
+ return 0;
+}
+
+static inline int tree_mod_alloc(struct btrfs_fs_info *fs_info, gfp_t flags,
+ struct tree_mod_elem **tm_ret)
+{
+ struct tree_mod_elem *tm;
+ int seq;
+
+ if (tree_mod_dont_log(fs_info, NULL))
+ return 0;
+
+ tm = *tm_ret = kzalloc(sizeof(*tm), flags);
+ if (!tm)
+ return -ENOMEM;
+
+ tm->elem.flags = 0;
+ spin_lock(&fs_info->tree_mod_seq_lock);
+ if (list_empty(&fs_info->tree_mod_seq_list)) {
+ /*
+ * someone emptied the list while we were waiting for the lock.
+ * we must not add to the list, because no blocker exists. items
+ * are removed from the list only when the existing blocker is
+ * removed from the list.
+ */
+ kfree(tm);
+ seq = 0;
+ } else {
+ __get_tree_mod_seq(fs_info, &tm->elem);
+ seq = tm->elem.seq;
+ }
+ spin_unlock(&fs_info->tree_mod_seq_lock);
+
+ return seq;
+}
+
+static noinline int
+tree_mod_log_insert_key_mask(struct btrfs_fs_info *fs_info,
+ struct extent_buffer *eb, int slot,
+ enum mod_log_op op, gfp_t flags)
+{
+ struct tree_mod_elem *tm;
+ int ret;
+
+ ret = tree_mod_alloc(fs_info, flags, &tm);
+ if (ret <= 0)
+ return ret;
+
+ tm->index = eb->start >> PAGE_CACHE_SHIFT;
+ if (op != MOD_LOG_KEY_ADD) {
+ btrfs_node_key(eb, &tm->key, slot);
+ tm->blockptr = btrfs_node_blockptr(eb, slot);
+ }
+ tm->op = op;
+ tm->slot = slot;
+ tm->generation = btrfs_node_ptr_generation(eb, slot);
+
+ return __tree_mod_log_insert(fs_info, tm);
+}
+
+static noinline int
+tree_mod_log_insert_key(struct btrfs_fs_info *fs_info, struct extent_buffer *eb,
+ int slot, enum mod_log_op op)
+{
+ return tree_mod_log_insert_key_mask(fs_info, eb, slot, op, GFP_NOFS);
+}
+
+static noinline int
+tree_mod_log_insert_move(struct btrfs_fs_info *fs_info,
+ struct extent_buffer *eb, int dst_slot, int src_slot,
+ int nr_items, gfp_t flags)
+{
+ struct tree_mod_elem *tm;
+ int ret;
+ int i;
+
+ if (tree_mod_dont_log(fs_info, eb))
+ return 0;
+
+ for (i = 0; i + dst_slot < src_slot && i < nr_items; i++) {
+ ret = tree_mod_log_insert_key(fs_info, eb, i + dst_slot,
+ MOD_LOG_KEY_REMOVE_WHILE_MOVING);
+ BUG_ON(ret < 0);
+ }
+
+ ret = tree_mod_alloc(fs_info, flags, &tm);
+ if (ret <= 0)
+ return ret;
+
+ tm->index = eb->start >> PAGE_CACHE_SHIFT;
+ tm->slot = src_slot;
+ tm->move.dst_slot = dst_slot;
+ tm->move.nr_items = nr_items;
+ tm->op = MOD_LOG_MOVE_KEYS;
+
+ return __tree_mod_log_insert(fs_info, tm);
+}
+
+static noinline int
+tree_mod_log_insert_root(struct btrfs_fs_info *fs_info,
+ struct extent_buffer *old_root,
+ struct extent_buffer *new_root, gfp_t flags)
+{
+ struct tree_mod_elem *tm;
+ int ret;
+
+ ret = tree_mod_alloc(fs_info, flags, &tm);
+ if (ret <= 0)
+ return ret;
+
+ tm->index = new_root->start >> PAGE_CACHE_SHIFT;
+ tm->old_root.logical = old_root->start;
+ tm->old_root.level = btrfs_header_level(old_root);
+ tm->generation = btrfs_header_generation(old_root);
+ tm->op = MOD_LOG_ROOT_REPLACE;
+
+ return __tree_mod_log_insert(fs_info, tm);
+}
+
+static struct tree_mod_elem *
+__tree_mod_log_search(struct btrfs_fs_info *fs_info, u64 start, u64 min_seq,
+ int smallest)
+{
+ struct rb_root *tm_root;
+ struct rb_node *node;
+ struct tree_mod_elem *cur = NULL;
+ struct tree_mod_elem *found = NULL;
+ u64 index = start >> PAGE_CACHE_SHIFT;
+
+ read_lock(&fs_info->tree_mod_log_lock);
+ tm_root = &fs_info->tree_mod_log;
+ node = tm_root->rb_node;
+ while (node) {
+ cur = container_of(node, struct tree_mod_elem, node);
+ if (cur->index < index) {
+ node = node->rb_left;
+ } else if (cur->index > index) {
+ node = node->rb_right;
+ } else if (cur->elem.seq < min_seq) {
+ node = node->rb_left;
+ } else if (!smallest) {
+ /* we want the node with the highest seq */
+ if (found)
+ BUG_ON(found->elem.seq > cur->elem.seq);
+ found = cur;
+ node = node->rb_left;
+ } else if (cur->elem.seq > min_seq) {
+ /* we want the node with the smallest seq */
+ if (found)
+ BUG_ON(found->elem.seq < cur->elem.seq);
+ found = cur;
+ node = node->rb_right;
+ } else {
+ found = cur;
+ break;
+ }
+ }
+ read_unlock(&fs_info->tree_mod_log_lock);
+
+ return found;
+}
+
+/*
+ * this returns the element from the log with the smallest time sequence
+ * value that's in the log (the oldest log item). any element with a time
+ * sequence lower than min_seq will be ignored.
+ */
+static struct tree_mod_elem *
+tree_mod_log_search_oldest(struct btrfs_fs_info *fs_info, u64 start,
+ u64 min_seq)
+{
+ return __tree_mod_log_search(fs_info, start, min_seq, 1);
+}
+
+/*
+ * this returns the element from the log with the largest time sequence
+ * value that's in the log (the most recent log item). any element with
+ * a time sequence lower than min_seq will be ignored.
+ */
+static struct tree_mod_elem *
+tree_mod_log_search(struct btrfs_fs_info *fs_info, u64 start, u64 min_seq)
+{
+ return __tree_mod_log_search(fs_info, start, min_seq, 0);
+}
+
+static inline void
+tree_mod_log_eb_copy(struct btrfs_fs_info *fs_info, struct extent_buffer *dst,
+ struct extent_buffer *src, unsigned long dst_offset,
+ unsigned long src_offset, int nr_items)
+{
+ int ret;
+ int i;
+
+ if (tree_mod_dont_log(fs_info, NULL))
+ return;
+
+ if (btrfs_header_level(dst) == 0 && btrfs_header_level(src) == 0)
+ return;
+
+ /* speed this up by single seq for all operations? */
+ for (i = 0; i < nr_items; i++) {
+ ret = tree_mod_log_insert_key(fs_info, src, i + src_offset,
+ MOD_LOG_KEY_REMOVE);
+ BUG_ON(ret < 0);
+ ret = tree_mod_log_insert_key(fs_info, dst, i + dst_offset,
+ MOD_LOG_KEY_ADD);
+ BUG_ON(ret < 0);
+ }
+}
+
+static inline void
+tree_mod_log_eb_move(struct btrfs_fs_info *fs_info, struct extent_buffer *dst,
+ int dst_offset, int src_offset, int nr_items)
+{
+ int ret;
+ ret = tree_mod_log_insert_move(fs_info, dst, dst_offset, src_offset,
+ nr_items, GFP_NOFS);
+ BUG_ON(ret < 0);
+}
+
+static inline void
+tree_mod_log_set_node_key(struct btrfs_fs_info *fs_info,
+ struct extent_buffer *eb,
+ struct btrfs_disk_key *disk_key, int slot, int atomic)
+{
+ int ret;
+
+ ret = tree_mod_log_insert_key_mask(fs_info, eb, slot,
+ MOD_LOG_KEY_REPLACE,
+ atomic ? GFP_ATOMIC : GFP_NOFS);
+ BUG_ON(ret < 0);
+}
+
+static void tree_mod_log_free_eb(struct btrfs_fs_info *fs_info,
+ struct extent_buffer *eb)
+{
+ int i;
+ int ret;
+ u32 nritems;
+
+ if (tree_mod_dont_log(fs_info, eb))
+ return;
+
+ nritems = btrfs_header_nritems(eb);
+ for (i = nritems - 1; i >= 0; i--) {
+ ret = tree_mod_log_insert_key(fs_info, eb, i,
+ MOD_LOG_KEY_REMOVE_WHILE_FREEING);
+ BUG_ON(ret < 0);
+ }
+}
+
+static inline void
+tree_mod_log_set_root_pointer(struct btrfs_root *root,
+ struct extent_buffer *new_root_node)
+{
+ int ret;
+ tree_mod_log_free_eb(root->fs_info, root->node);
+ ret = tree_mod_log_insert_root(root->fs_info, root->node,
+ new_root_node, GFP_NOFS);
+ BUG_ON(ret < 0);
+}
+
/*
* check if the tree block can be shared by multiple trees
*/
@@ -409,6 +847,12 @@
ret = btrfs_dec_ref(trans, root, buf, 1, 1);
BUG_ON(ret); /* -ENOMEM */
}
+ /*
+ * don't log freeing in case we're freeing the root node, this
+ * is done by tree_mod_log_set_root_pointer later
+ */
+ if (buf != root->node && btrfs_header_level(buf) != 0)
+ tree_mod_log_free_eb(root->fs_info, buf);
clean_tree_block(trans, root, buf);
*last_ref = 1;
}
@@ -467,7 +911,7 @@
cow = btrfs_alloc_free_block(trans, root, buf->len, parent_start,
root->root_key.objectid, &disk_key,
- level, search_start, empty_size, 1);
+ level, search_start, empty_size);
if (IS_ERR(cow))
return PTR_ERR(cow);
@@ -506,10 +950,11 @@
parent_start = 0;
extent_buffer_get(cow);
+ tree_mod_log_set_root_pointer(root, cow);
rcu_assign_pointer(root->node, cow);
btrfs_free_tree_block(trans, root, buf, parent_start,
- last_ref, 1);
+ last_ref);
free_extent_buffer(buf);
add_root_to_dirty_list(root);
} else {
@@ -519,13 +964,15 @@
parent_start = 0;
WARN_ON(trans->transid != btrfs_header_generation(parent));
+ tree_mod_log_insert_key(root->fs_info, parent, parent_slot,
+ MOD_LOG_KEY_REPLACE);
btrfs_set_node_blockptr(parent, parent_slot,
cow->start);
btrfs_set_node_ptr_generation(parent, parent_slot,
trans->transid);
btrfs_mark_buffer_dirty(parent);
btrfs_free_tree_block(trans, root, buf, parent_start,
- last_ref, 1);
+ last_ref);
}
if (unlock_orig)
btrfs_tree_unlock(buf);
@@ -535,6 +982,210 @@
return 0;
}
+/*
+ * returns the logical address of the oldest predecessor of the given root.
+ * entries older than time_seq are ignored.
+ */
+static struct tree_mod_elem *
+__tree_mod_log_oldest_root(struct btrfs_fs_info *fs_info,
+ struct btrfs_root *root, u64 time_seq)
+{
+ struct tree_mod_elem *tm;
+ struct tree_mod_elem *found = NULL;
+ u64 root_logical = root->node->start;
+ int looped = 0;
+
+ if (!time_seq)
+ return 0;
+
+ /*
+ * the very last operation that's logged for a root is the replacement
+ * operation (if it is replaced at all). this has the index of the *new*
+ * root, making it the very first operation that's logged for this root.
+ */
+ while (1) {
+ tm = tree_mod_log_search_oldest(fs_info, root_logical,
+ time_seq);
+ if (!looped && !tm)
+ return 0;
+ /*
+ * we must have key remove operations in the log before the
+ * replace operation.
+ */
+ BUG_ON(!tm);
+
+ if (tm->op != MOD_LOG_ROOT_REPLACE)
+ break;
+
+ found = tm;
+ root_logical = tm->old_root.logical;
+ BUG_ON(root_logical == root->node->start);
+ looped = 1;
+ }
+
+ return found;
+}
+
+/*
+ * tm is a pointer to the first operation to rewind within eb. then, all
+ * previous operations will be rewinded (until we reach something older than
+ * time_seq).
+ */
+static void
+__tree_mod_log_rewind(struct extent_buffer *eb, u64 time_seq,
+ struct tree_mod_elem *first_tm)
+{
+ u32 n;
+ struct rb_node *next;
+ struct tree_mod_elem *tm = first_tm;
+ unsigned long o_dst;
+ unsigned long o_src;
+ unsigned long p_size = sizeof(struct btrfs_key_ptr);
+
+ n = btrfs_header_nritems(eb);
+ while (tm && tm->elem.seq >= time_seq) {
+ /*
+ * all the operations are recorded with the operator used for
+ * the modification. as we're going backwards, we do the
+ * opposite of each operation here.
+ */
+ switch (tm->op) {
+ case MOD_LOG_KEY_REMOVE_WHILE_FREEING:
+ BUG_ON(tm->slot < n);
+ case MOD_LOG_KEY_REMOVE_WHILE_MOVING:
+ case MOD_LOG_KEY_REMOVE:
+ btrfs_set_node_key(eb, &tm->key, tm->slot);
+ btrfs_set_node_blockptr(eb, tm->slot, tm->blockptr);
+ btrfs_set_node_ptr_generation(eb, tm->slot,
+ tm->generation);
+ n++;
+ break;
+ case MOD_LOG_KEY_REPLACE:
+ BUG_ON(tm->slot >= n);
+ btrfs_set_node_key(eb, &tm->key, tm->slot);
+ btrfs_set_node_blockptr(eb, tm->slot, tm->blockptr);
+ btrfs_set_node_ptr_generation(eb, tm->slot,
+ tm->generation);
+ break;
+ case MOD_LOG_KEY_ADD:
+ if (tm->slot != n - 1) {
+ o_dst = btrfs_node_key_ptr_offset(tm->slot);
+ o_src = btrfs_node_key_ptr_offset(tm->slot + 1);
+ memmove_extent_buffer(eb, o_dst, o_src, p_size);
+ }
+ n--;
+ break;
+ case MOD_LOG_MOVE_KEYS:
+ o_dst = btrfs_node_key_ptr_offset(tm->slot);
+ o_src = btrfs_node_key_ptr_offset(tm->move.dst_slot);
+ memmove_extent_buffer(eb, o_dst, o_src,
+ tm->move.nr_items * p_size);
+ break;
+ case MOD_LOG_ROOT_REPLACE:
+ /*
+ * this operation is special. for roots, this must be
+ * handled explicitly before rewinding.
+ * for non-roots, this operation may exist if the node
+ * was a root: root A -> child B; then A gets empty and
+ * B is promoted to the new root. in the mod log, we'll
+ * have a root-replace operation for B, a tree block
+ * that is no root. we simply ignore that operation.
+ */
+ break;
+ }
+ next = rb_next(&tm->node);
+ if (!next)
+ break;
+ tm = container_of(next, struct tree_mod_elem, node);
+ if (tm->index != first_tm->index)
+ break;
+ }
+ btrfs_set_header_nritems(eb, n);
+}
+
+static struct extent_buffer *
+tree_mod_log_rewind(struct btrfs_fs_info *fs_info, struct extent_buffer *eb,
+ u64 time_seq)
+{
+ struct extent_buffer *eb_rewin;
+ struct tree_mod_elem *tm;
+
+ if (!time_seq)
+ return eb;
+
+ if (btrfs_header_level(eb) == 0)
+ return eb;
+
+ tm = tree_mod_log_search(fs_info, eb->start, time_seq);
+ if (!tm)
+ return eb;
+
+ if (tm->op == MOD_LOG_KEY_REMOVE_WHILE_FREEING) {
+ BUG_ON(tm->slot != 0);
+ eb_rewin = alloc_dummy_extent_buffer(eb->start,
+ fs_info->tree_root->nodesize);
+ BUG_ON(!eb_rewin);
+ btrfs_set_header_bytenr(eb_rewin, eb->start);
+ btrfs_set_header_backref_rev(eb_rewin,
+ btrfs_header_backref_rev(eb));
+ btrfs_set_header_owner(eb_rewin, btrfs_header_owner(eb));
+ btrfs_set_header_level(eb_rewin, btrfs_header_level(eb));
+ } else {
+ eb_rewin = btrfs_clone_extent_buffer(eb);
+ BUG_ON(!eb_rewin);
+ }
+
+ extent_buffer_get(eb_rewin);
+ free_extent_buffer(eb);
+
+ __tree_mod_log_rewind(eb_rewin, time_seq, tm);
+
+ return eb_rewin;
+}
+
+static inline struct extent_buffer *
+get_old_root(struct btrfs_root *root, u64 time_seq)
+{
+ struct tree_mod_elem *tm;
+ struct extent_buffer *eb;
+ struct tree_mod_root *old_root;
+ u64 old_generation;
+
+ tm = __tree_mod_log_oldest_root(root->fs_info, root, time_seq);
+ if (!tm)
+ return root->node;
+
+ old_root = &tm->old_root;
+ old_generation = tm->generation;
+
+ tm = tree_mod_log_search(root->fs_info, old_root->logical, time_seq);
+ /*
+ * there was an item in the log when __tree_mod_log_oldest_root
+ * returned. this one must not go away, because the time_seq passed to
+ * us must be blocking its removal.
+ */
+ BUG_ON(!tm);
+
+ if (old_root->logical == root->node->start) {
+ /* there are logged operations for the current root */
+ eb = btrfs_clone_extent_buffer(root->node);
+ } else {
+ /* there's a root replace operation for the current root */
+ eb = alloc_dummy_extent_buffer(tm->index << PAGE_CACHE_SHIFT,
+ root->nodesize);
+ btrfs_set_header_bytenr(eb, eb->start);
+ btrfs_set_header_backref_rev(eb, BTRFS_MIXED_BACKREF_REV);
+ btrfs_set_header_owner(eb, root->root_key.objectid);
+ }
+ if (!eb)
+ return NULL;
+ btrfs_set_header_level(eb, old_root->level);
+ btrfs_set_header_generation(eb, old_generation);
+ __tree_mod_log_rewind(eb, time_seq, tm);
+
+ return eb;
+}
+
static inline int should_cow_block(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
struct extent_buffer *buf)
@@ -976,6 +1627,7 @@
goto enospc;
}
+ tree_mod_log_set_root_pointer(root, child);
rcu_assign_pointer(root->node, child);
add_root_to_dirty_list(root);
@@ -989,7 +1641,7 @@
free_extent_buffer(mid);
root_sub_used(root, mid->len);
- btrfs_free_tree_block(trans, root, mid, 0, 1, 0);
+ btrfs_free_tree_block(trans, root, mid, 0, 1);
/* once for the root ptr */
free_extent_buffer_stale(mid);
return 0;
@@ -1042,14 +1694,16 @@
if (btrfs_header_nritems(right) == 0) {
clean_tree_block(trans, root, right);
btrfs_tree_unlock(right);
- del_ptr(trans, root, path, level + 1, pslot + 1);
+ del_ptr(trans, root, path, level + 1, pslot + 1, 1);
root_sub_used(root, right->len);
- btrfs_free_tree_block(trans, root, right, 0, 1, 0);
+ btrfs_free_tree_block(trans, root, right, 0, 1);
free_extent_buffer_stale(right);
right = NULL;
} else {
struct btrfs_disk_key right_key;
btrfs_node_key(right, &right_key, 0);
+ tree_mod_log_set_node_key(root->fs_info, parent,
+ &right_key, pslot + 1, 0);
btrfs_set_node_key(parent, &right_key, pslot + 1);
btrfs_mark_buffer_dirty(parent);
}
@@ -1084,15 +1738,17 @@
if (btrfs_header_nritems(mid) == 0) {
clean_tree_block(trans, root, mid);
btrfs_tree_unlock(mid);
- del_ptr(trans, root, path, level + 1, pslot);
+ del_ptr(trans, root, path, level + 1, pslot, 1);
root_sub_used(root, mid->len);
- btrfs_free_tree_block(trans, root, mid, 0, 1, 0);
+ btrfs_free_tree_block(trans, root, mid, 0, 1);
free_extent_buffer_stale(mid);
mid = NULL;
} else {
/* update the parent key to reflect our changes */
struct btrfs_disk_key mid_key;
btrfs_node_key(mid, &mid_key, 0);
+ tree_mod_log_set_node_key(root->fs_info, parent, &mid_key,
+ pslot, 0);
btrfs_set_node_key(parent, &mid_key, pslot);
btrfs_mark_buffer_dirty(parent);
}
@@ -1190,6 +1846,8 @@
struct btrfs_disk_key disk_key;
orig_slot += left_nr;
btrfs_node_key(mid, &disk_key, 0);
+ tree_mod_log_set_node_key(root->fs_info, parent,
+ &disk_key, pslot, 0);
btrfs_set_node_key(parent, &disk_key, pslot);
btrfs_mark_buffer_dirty(parent);
if (btrfs_header_nritems(left) > orig_slot) {
@@ -1241,6 +1899,8 @@
struct btrfs_disk_key disk_key;
btrfs_node_key(right, &disk_key, 0);
+ tree_mod_log_set_node_key(root->fs_info, parent,
+ &disk_key, pslot + 1, 0);
btrfs_set_node_key(parent, &disk_key, pslot + 1);
btrfs_mark_buffer_dirty(parent);
@@ -1498,7 +2158,7 @@
read_block_for_search(struct btrfs_trans_handle *trans,
struct btrfs_root *root, struct btrfs_path *p,
struct extent_buffer **eb_ret, int level, int slot,
- struct btrfs_key *key)
+ struct btrfs_key *key, u64 time_seq)
{
u64 blocknr;
u64 gen;
@@ -1852,7 +2512,7 @@
}
err = read_block_for_search(trans, root, p,
- &b, level, slot, key);
+ &b, level, slot, key, 0);
if (err == -EAGAIN)
goto again;
if (err) {
@@ -1924,6 +2584,115 @@
}
/*
+ * Like btrfs_search_slot, this looks for a key in the given tree. It uses the
+ * current state of the tree together with the operations recorded in the tree
+ * modification log to search for the key in a previous version of this tree, as
+ * denoted by the time_seq parameter.
+ *
+ * Naturally, there is no support for insert, delete or cow operations.
+ *
+ * The resulting path and return value will be set up as if we called
+ * btrfs_search_slot at that point in time with ins_len and cow both set to 0.
+ */
+int btrfs_search_old_slot(struct btrfs_root *root, struct btrfs_key *key,
+ struct btrfs_path *p, u64 time_seq)
+{
+ struct extent_buffer *b;
+ int slot;
+ int ret;
+ int err;
+ int level;
+ int lowest_unlock = 1;
+ u8 lowest_level = 0;
+
+ lowest_level = p->lowest_level;
+ WARN_ON(p->nodes[0] != NULL);
+
+ if (p->search_commit_root) {
+ BUG_ON(time_seq);
+ return btrfs_search_slot(NULL, root, key, p, 0, 0);
+ }
+
+again:
+ b = get_old_root(root, time_seq);
+ extent_buffer_get(b);
+ level = btrfs_header_level(b);
+ btrfs_tree_read_lock(b);
+ p->locks[level] = BTRFS_READ_LOCK;
+
+ while (b) {
+ level = btrfs_header_level(b);
+ p->nodes[level] = b;
+ btrfs_clear_path_blocking(p, NULL, 0);
+
+ /*
+ * we have a lock on b and as long as we aren't changing
+ * the tree, there is no way to for the items in b to change.
+ * It is safe to drop the lock on our parent before we
+ * go through the expensive btree search on b.
+ */
+ btrfs_unlock_up_safe(p, level + 1);
+
+ ret = bin_search(b, key, level, &slot);
+
+ if (level != 0) {
+ int dec = 0;
+ if (ret && slot > 0) {
+ dec = 1;
+ slot -= 1;
+ }
+ p->slots[level] = slot;
+ unlock_up(p, level, lowest_unlock, 0, NULL);
+
+ if (level == lowest_level) {
+ if (dec)
+ p->slots[level]++;
+ goto done;
+ }
+
+ err = read_block_for_search(NULL, root, p, &b, level,
+ slot, key, time_seq);
+ if (err == -EAGAIN)
+ goto again;
+ if (err) {
+ ret = err;
+ goto done;
+ }
+
+ level = btrfs_header_level(b);
+ err = btrfs_try_tree_read_lock(b);
+ if (!err) {
+ btrfs_set_path_blocking(p);
+ btrfs_tree_read_lock(b);
+ btrfs_clear_path_blocking(p, b,
+ BTRFS_READ_LOCK);
+ }
+ p->locks[level] = BTRFS_READ_LOCK;
+ p->nodes[level] = b;
+ b = tree_mod_log_rewind(root->fs_info, b, time_seq);
+ if (b != p->nodes[level]) {
+ btrfs_tree_unlock_rw(p->nodes[level],
+ p->locks[level]);
+ p->locks[level] = 0;
+ p->nodes[level] = b;
+ }
+ } else {
+ p->slots[level] = slot;
+ unlock_up(p, level, lowest_unlock, 0, NULL);
+ goto done;
+ }
+ }
+ ret = 1;
+done:
+ if (!p->leave_spinning)
+ btrfs_set_path_blocking(p);
+ if (ret < 0)
+ btrfs_release_path(p);
+
+ return ret;
+}
+
+/*
* adjust the pointers going up the tree, starting at level
* making sure the right key of each node is points to 'key'.
* This is used after shifting pointers to the left, so it stops
@@ -1943,6 +2712,7 @@
if (!path->nodes[i])
break;
t = path->nodes[i];
+ tree_mod_log_set_node_key(root->fs_info, t, key, tslot, 1);
btrfs_set_node_key(t, key, tslot);
btrfs_mark_buffer_dirty(path->nodes[i]);
if (tslot != 0)
@@ -2025,12 +2795,16 @@
} else
push_items = min(src_nritems - 8, push_items);
+ tree_mod_log_eb_copy(root->fs_info, dst, src, dst_nritems, 0,
+ push_items);
copy_extent_buffer(dst, src,
btrfs_node_key_ptr_offset(dst_nritems),
btrfs_node_key_ptr_offset(0),
push_items * sizeof(struct btrfs_key_ptr));
if (push_items < src_nritems) {
+ tree_mod_log_eb_move(root->fs_info, src, 0, push_items,
+ src_nritems - push_items);
memmove_extent_buffer(src, btrfs_node_key_ptr_offset(0),
btrfs_node_key_ptr_offset(push_items),
(src_nritems - push_items) *
@@ -2084,11 +2858,14 @@
if (max_push < push_items)
push_items = max_push;
+ tree_mod_log_eb_move(root->fs_info, dst, push_items, 0, dst_nritems);
memmove_extent_buffer(dst, btrfs_node_key_ptr_offset(push_items),
btrfs_node_key_ptr_offset(0),
(dst_nritems) *
sizeof(struct btrfs_key_ptr));
+ tree_mod_log_eb_copy(root->fs_info, dst, src, 0,
+ src_nritems - push_items, push_items);
copy_extent_buffer(dst, src,
btrfs_node_key_ptr_offset(0),
btrfs_node_key_ptr_offset(src_nritems - push_items),
@@ -2131,7 +2908,7 @@
c = btrfs_alloc_free_block(trans, root, root->nodesize, 0,
root->root_key.objectid, &lower_key,
- level, root->node->start, 0, 0);
+ level, root->node->start, 0);
if (IS_ERR(c))
return PTR_ERR(c);
@@ -2163,6 +2940,7 @@
btrfs_mark_buffer_dirty(c);
old = root->node;
+ tree_mod_log_set_root_pointer(root, c);
rcu_assign_pointer(root->node, c);
/* the super has an extra ref to root->node */
@@ -2186,10 +2964,11 @@
static void insert_ptr(struct btrfs_trans_handle *trans,
struct btrfs_root *root, struct btrfs_path *path,
struct btrfs_disk_key *key, u64 bytenr,
- int slot, int level)
+ int slot, int level, int tree_mod_log)
{
struct extent_buffer *lower;
int nritems;
+ int ret;
BUG_ON(!path->nodes[level]);
btrfs_assert_tree_locked(path->nodes[level]);
@@ -2198,11 +2977,19 @@
BUG_ON(slot > nritems);
BUG_ON(nritems == BTRFS_NODEPTRS_PER_BLOCK(root));
if (slot != nritems) {
+ if (tree_mod_log && level)
+ tree_mod_log_eb_move(root->fs_info, lower, slot + 1,
+ slot, nritems - slot);
memmove_extent_buffer(lower,
btrfs_node_key_ptr_offset(slot + 1),
btrfs_node_key_ptr_offset(slot),
(nritems - slot) * sizeof(struct btrfs_key_ptr));
}
+ if (tree_mod_log && level) {
+ ret = tree_mod_log_insert_key(root->fs_info, lower, slot,
+ MOD_LOG_KEY_ADD);
+ BUG_ON(ret < 0);
+ }
btrfs_set_node_key(lower, key, slot);
btrfs_set_node_blockptr(lower, slot, bytenr);
WARN_ON(trans->transid == 0);
@@ -2254,7 +3041,7 @@
split = btrfs_alloc_free_block(trans, root, root->nodesize, 0,
root->root_key.objectid,
- &disk_key, level, c->start, 0, 0);
+ &disk_key, level, c->start, 0);
if (IS_ERR(split))
return PTR_ERR(split);
@@ -2273,7 +3060,7 @@
(unsigned long)btrfs_header_chunk_tree_uuid(split),
BTRFS_UUID_SIZE);
-
+ tree_mod_log_eb_copy(root->fs_info, split, c, 0, mid, c_nritems - mid);
copy_extent_buffer(split, c,
btrfs_node_key_ptr_offset(0),
btrfs_node_key_ptr_offset(mid),
@@ -2286,7 +3073,7 @@
btrfs_mark_buffer_dirty(split);
insert_ptr(trans, root, path, &disk_key, split->start,
- path->slots[level + 1] + 1, level + 1);
+ path->slots[level + 1] + 1, level + 1, 1);
if (path->slots[level] >= mid) {
path->slots[level] -= mid;
@@ -2823,7 +3610,7 @@
btrfs_set_header_nritems(l, mid);
btrfs_item_key(right, &disk_key, 0);
insert_ptr(trans, root, path, &disk_key, right->start,
- path->slots[1] + 1, 1);
+ path->slots[1] + 1, 1, 0);
btrfs_mark_buffer_dirty(right);
btrfs_mark_buffer_dirty(l);
@@ -3006,7 +3793,7 @@
right = btrfs_alloc_free_block(trans, root, root->leafsize, 0,
root->root_key.objectid,
- &disk_key, 0, l->start, 0, 0);
+ &disk_key, 0, l->start, 0);
if (IS_ERR(right))
return PTR_ERR(right);
@@ -3030,7 +3817,7 @@
if (mid <= slot) {
btrfs_set_header_nritems(right, 0);
insert_ptr(trans, root, path, &disk_key, right->start,
- path->slots[1] + 1, 1);
+ path->slots[1] + 1, 1, 0);
btrfs_tree_unlock(path->nodes[0]);
free_extent_buffer(path->nodes[0]);
path->nodes[0] = right;
@@ -3039,7 +3826,7 @@
} else {
btrfs_set_header_nritems(right, 0);
insert_ptr(trans, root, path, &disk_key, right->start,
- path->slots[1], 1);
+ path->slots[1], 1, 0);
btrfs_tree_unlock(path->nodes[0]);
free_extent_buffer(path->nodes[0]);
path->nodes[0] = right;
@@ -3751,19 +4538,29 @@
* empty a node.
*/
static void del_ptr(struct btrfs_trans_handle *trans, struct btrfs_root *root,
- struct btrfs_path *path, int level, int slot)
+ struct btrfs_path *path, int level, int slot,
+ int tree_mod_log)
{
struct extent_buffer *parent = path->nodes[level];
u32 nritems;
+ int ret;
nritems = btrfs_header_nritems(parent);
if (slot != nritems - 1) {
+ if (tree_mod_log && level)
+ tree_mod_log_eb_move(root->fs_info, parent, slot,
+ slot + 1, nritems - slot - 1);
memmove_extent_buffer(parent,
btrfs_node_key_ptr_offset(slot),
btrfs_node_key_ptr_offset(slot + 1),
sizeof(struct btrfs_key_ptr) *
(nritems - slot - 1));
+ } else if (tree_mod_log && level) {
+ ret = tree_mod_log_insert_key(root->fs_info, parent, slot,
+ MOD_LOG_KEY_REMOVE);
+ BUG_ON(ret < 0);
}
+
nritems--;
btrfs_set_header_nritems(parent, nritems);
if (nritems == 0 && parent == root->node) {
@@ -3795,7 +4592,7 @@
struct extent_buffer *leaf)
{
WARN_ON(btrfs_header_generation(leaf) != trans->transid);
- del_ptr(trans, root, path, 1, path->slots[1]);
+ del_ptr(trans, root, path, 1, path->slots[1], 1);
/*
* btrfs_free_extent is expensive, we want to make sure we
@@ -3806,7 +4603,7 @@
root_sub_used(root, leaf->len);
extent_buffer_get(leaf);
- btrfs_free_tree_block(trans, root, leaf, 0, 1, 0);
+ btrfs_free_tree_block(trans, root, leaf, 0, 1);
free_extent_buffer_stale(leaf);
}
/*
@@ -4273,7 +5070,7 @@
next = c;
next_rw_lock = path->locks[level];
ret = read_block_for_search(NULL, root, path, &next, level,
- slot, &key);
+ slot, &key, 0);
if (ret == -EAGAIN)
goto again;
@@ -4310,7 +5107,7 @@
break;
ret = read_block_for_search(NULL, root, path, &next, level,
- 0, &key);
+ 0, &key, 0);
if (ret == -EAGAIN)
goto again;
diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index 1c665eb..0151ca1 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -1140,6 +1140,15 @@
spinlock_t delayed_iput_lock;
struct list_head delayed_iputs;
+ /* this protects tree_mod_seq_list */
+ spinlock_t tree_mod_seq_lock;
+ atomic_t tree_mod_seq;
+ struct list_head tree_mod_seq_list;
+
+ /* this protects tree_mod_log */
+ rwlock_t tree_mod_log_lock;
+ struct rb_root tree_mod_log;
+
atomic_t nr_async_submits;
atomic_t async_submit_draining;
atomic_t nr_async_bios;
@@ -2537,11 +2546,11 @@
struct btrfs_root *root, u32 blocksize,
u64 parent, u64 root_objectid,
struct btrfs_disk_key *key, int level,
- u64 hint, u64 empty_size, int for_cow);
+ u64 hint, u64 empty_size);
void btrfs_free_tree_block(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
struct extent_buffer *buf,
- u64 parent, int last_ref, int for_cow);
+ u64 parent, int last_ref);
struct extent_buffer *btrfs_init_new_buffer(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
u64 bytenr, u32 blocksize,
@@ -2700,6 +2709,8 @@
int btrfs_search_slot(struct btrfs_trans_handle *trans, struct btrfs_root
*root, struct btrfs_key *key, struct btrfs_path *p, int
ins_len, int cow);
+int btrfs_search_old_slot(struct btrfs_root *root, struct btrfs_key *key,
+ struct btrfs_path *p, u64 time_seq);
int btrfs_realloc_node(struct btrfs_trans_handle *trans,
struct btrfs_root *root, struct extent_buffer *parent,
int start_slot, int cache_only, u64 *last_ret,
@@ -3139,4 +3150,23 @@
int btree_readahead_hook(struct btrfs_root *root, struct extent_buffer *eb,
u64 start, int err);
+/* delayed seq elem */
+struct seq_list {
+ struct list_head list;
+ u64 seq;
+ u32 flags;
+};
+
+void btrfs_get_tree_mod_seq(struct btrfs_fs_info *fs_info,
+ struct seq_list *elem);
+void btrfs_put_tree_mod_seq(struct btrfs_fs_info *fs_info,
+ struct seq_list *elem);
+
+static inline int is_fstree(u64 rootid)
+{
+ if (rootid == BTRFS_FS_TREE_OBJECTID ||
+ (s64)rootid >= (s64)BTRFS_FIRST_FREE_OBJECTID)
+ return 1;
+ return 0;
+}
#endif
diff --git a/fs/btrfs/delayed-ref.c b/fs/btrfs/delayed-ref.c
index 69f22e3..13ae7b0 100644
--- a/fs/btrfs/delayed-ref.c
+++ b/fs/btrfs/delayed-ref.c
@@ -525,7 +525,7 @@
ref->is_head = 0;
ref->in_tree = 1;
- if (need_ref_seq(for_cow, ref_root))
+ if (is_fstree(ref_root))
seq = inc_delayed_seq(delayed_refs);
ref->seq = seq;
@@ -584,7 +584,7 @@
ref->is_head = 0;
ref->in_tree = 1;
- if (need_ref_seq(for_cow, ref_root))
+ if (is_fstree(ref_root))
seq = inc_delayed_seq(delayed_refs);
ref->seq = seq;
@@ -658,10 +658,11 @@
add_delayed_tree_ref(fs_info, trans, &ref->node, bytenr,
num_bytes, parent, ref_root, level, action,
for_cow);
- if (!need_ref_seq(for_cow, ref_root) &&
+ if (!is_fstree(ref_root) &&
waitqueue_active(&delayed_refs->seq_wait))
wake_up(&delayed_refs->seq_wait);
spin_unlock(&delayed_refs->lock);
+
return 0;
}
@@ -706,10 +707,11 @@
add_delayed_data_ref(fs_info, trans, &ref->node, bytenr,
num_bytes, parent, ref_root, owner, offset,
action, for_cow);
- if (!need_ref_seq(for_cow, ref_root) &&
+ if (!is_fstree(ref_root) &&
waitqueue_active(&delayed_refs->seq_wait))
wake_up(&delayed_refs->seq_wait);
spin_unlock(&delayed_refs->lock);
+
return 0;
}
diff --git a/fs/btrfs/delayed-ref.h b/fs/btrfs/delayed-ref.h
index d8f244d..413927f 100644
--- a/fs/btrfs/delayed-ref.h
+++ b/fs/btrfs/delayed-ref.h
@@ -195,11 +195,6 @@
int btrfs_find_ref_cluster(struct btrfs_trans_handle *trans,
struct list_head *cluster, u64 search_start);
-struct seq_list {
- struct list_head list;
- u64 seq;
-};
-
static inline u64 inc_delayed_seq(struct btrfs_delayed_ref_root *delayed_refs)
{
assert_spin_locked(&delayed_refs->lock);
@@ -230,25 +225,6 @@
u64 seq);
/*
- * delayed refs with a ref_seq > 0 must be held back during backref walking.
- * this only applies to items in one of the fs-trees. for_cow items never need
- * to be held back, so they won't get a ref_seq number.
- */
-static inline int need_ref_seq(int for_cow, u64 rootid)
-{
- if (for_cow)
- return 0;
-
- if (rootid == BTRFS_FS_TREE_OBJECTID)
- return 1;
-
- if ((s64)rootid >= (s64)BTRFS_FIRST_FREE_OBJECTID)
- return 1;
-
- return 0;
-}
-
-/*
* a node might live in a head or a regular ref, this lets you
* test for the proper type to use.
*/
diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index b0d49e2..b99d512 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -1252,7 +1252,7 @@
leaf = btrfs_alloc_free_block(trans, root, root->leafsize, 0,
BTRFS_TREE_LOG_OBJECTID, NULL,
- 0, 0, 0, 0);
+ 0, 0, 0);
if (IS_ERR(leaf)) {
kfree(root);
return ERR_CAST(leaf);
@@ -1914,11 +1914,14 @@
spin_lock_init(&fs_info->delayed_iput_lock);
spin_lock_init(&fs_info->defrag_inodes_lock);
spin_lock_init(&fs_info->free_chunk_lock);
+ spin_lock_init(&fs_info->tree_mod_seq_lock);
+ rwlock_init(&fs_info->tree_mod_log_lock);
mutex_init(&fs_info->reloc_mutex);
init_completion(&fs_info->kobj_unregister);
INIT_LIST_HEAD(&fs_info->dirty_cowonly_roots);
INIT_LIST_HEAD(&fs_info->space_info);
+ INIT_LIST_HEAD(&fs_info->tree_mod_seq_list);
btrfs_mapping_init(&fs_info->mapping_tree);
btrfs_init_block_rsv(&fs_info->global_block_rsv);
btrfs_init_block_rsv(&fs_info->delalloc_block_rsv);
@@ -1931,12 +1934,14 @@
atomic_set(&fs_info->async_submit_draining, 0);
atomic_set(&fs_info->nr_async_bios, 0);
atomic_set(&fs_info->defrag_running, 0);
+ atomic_set(&fs_info->tree_mod_seq, 0);
fs_info->sb = sb;
fs_info->max_inline = 8192 * 1024;
fs_info->metadata_ratio = 0;
fs_info->defrag_inodes = RB_ROOT;
fs_info->trans_no_join = 0;
fs_info->free_chunk_space = 0;
+ fs_info->tree_mod_log = RB_ROOT;
/* readahead state */
INIT_RADIX_TREE(&fs_info->reada_tree, GFP_NOFS & ~__GFP_WAIT);
diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index 1902726..4b5a1e1 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -5218,7 +5218,7 @@
void btrfs_free_tree_block(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
struct extent_buffer *buf,
- u64 parent, int last_ref, int for_cow)
+ u64 parent, int last_ref)
{
struct btrfs_block_group_cache *cache = NULL;
int ret;
@@ -5228,7 +5228,7 @@
buf->start, buf->len,
parent, root->root_key.objectid,
btrfs_header_level(buf),
- BTRFS_DROP_DELAYED_REF, NULL, for_cow);
+ BTRFS_DROP_DELAYED_REF, NULL, 0);
BUG_ON(ret); /* -ENOMEM */
}
@@ -6250,7 +6250,7 @@
struct btrfs_root *root, u32 blocksize,
u64 parent, u64 root_objectid,
struct btrfs_disk_key *key, int level,
- u64 hint, u64 empty_size, int for_cow)
+ u64 hint, u64 empty_size)
{
struct btrfs_key ins;
struct btrfs_block_rsv *block_rsv;
@@ -6298,7 +6298,7 @@
ins.objectid,
ins.offset, parent, root_objectid,
level, BTRFS_ADD_DELAYED_EXTENT,
- extent_op, for_cow);
+ extent_op, 0);
BUG_ON(ret); /* -ENOMEM */
}
return buf;
@@ -6716,7 +6716,7 @@
btrfs_header_owner(path->nodes[level + 1]));
}
- btrfs_free_tree_block(trans, root, eb, parent, wc->refs[level] == 1, 0);
+ btrfs_free_tree_block(trans, root, eb, parent, wc->refs[level] == 1);
out:
wc->refs[level] = 0;
wc->flags[level] = 0;
diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c
index b3692c1..2c8f7b2 100644
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -3924,6 +3924,7 @@
eb->start = start;
eb->len = len;
eb->tree = tree;
+ eb->bflags = 0;
rwlock_init(&eb->lock);
atomic_set(&eb->write_locks, 0);
atomic_set(&eb->read_locks, 0);
@@ -3961,6 +3962,60 @@
return eb;
}
+struct extent_buffer *btrfs_clone_extent_buffer(struct extent_buffer *src)
+{
+ unsigned long i;
+ struct page *p;
+ struct extent_buffer *new;
+ unsigned long num_pages = num_extent_pages(src->start, src->len);
+
+ new = __alloc_extent_buffer(NULL, src->start, src->len, GFP_ATOMIC);
+ if (new == NULL)
+ return NULL;
+
+ for (i = 0; i < num_pages; i++) {
+ p = alloc_page(GFP_ATOMIC);
+ BUG_ON(!p);
+ attach_extent_buffer_page(new, p);
+ WARN_ON(PageDirty(p));
+ SetPageUptodate(p);
+ new->pages[i] = p;
+ }
+
+ copy_extent_buffer(new, src, 0, 0, src->len);
+ set_bit(EXTENT_BUFFER_UPTODATE, &new->bflags);
+ set_bit(EXTENT_BUFFER_DUMMY, &new->bflags);
+
+ return new;
+}
+
+struct extent_buffer *alloc_dummy_extent_buffer(u64 start, unsigned long len)
+{
+ struct extent_buffer *eb;
+ unsigned long num_pages = num_extent_pages(0, len);
+ unsigned long i;
+
+ eb = __alloc_extent_buffer(NULL, start, len, GFP_ATOMIC);
+ if (!eb)
+ return NULL;
+
+ for (i = 0; i < num_pages; i++) {
+ eb->pages[i] = alloc_page(GFP_ATOMIC);
+ if (!eb->pages[i])
+ goto err;
+ }
+ set_extent_buffer_uptodate(eb);
+ btrfs_set_header_nritems(eb, 0);
+ set_bit(EXTENT_BUFFER_DUMMY, &eb->bflags);
+
+ return eb;
+err:
+ for (i--; i > 0; i--)
+ __free_page(eb->pages[i]);
+ __free_extent_buffer(eb);
+ return NULL;
+}
+
static int extent_buffer_under_io(struct extent_buffer *eb)
{
return (atomic_read(&eb->io_pages) ||
@@ -3977,6 +4032,7 @@
unsigned long index;
unsigned long num_pages;
struct page *page;
+ int mapped = !test_bit(EXTENT_BUFFER_DUMMY, &eb->bflags);
BUG_ON(extent_buffer_under_io(eb));
@@ -3988,7 +4044,7 @@
do {
index--;
page = extent_buffer_page(eb, index);
- if (page) {
+ if (page && mapped) {
spin_lock(&page->mapping->private_lock);
/*
* We do this since we'll remove the pages after we've
@@ -4013,6 +4069,8 @@
}
spin_unlock(&page->mapping->private_lock);
+ }
+ if (page) {
/* One for when we alloced the page */
page_cache_release(page);
}
@@ -4231,14 +4289,18 @@
{
WARN_ON(atomic_read(&eb->refs) == 0);
if (atomic_dec_and_test(&eb->refs)) {
- struct extent_io_tree *tree = eb->tree;
+ if (test_bit(EXTENT_BUFFER_DUMMY, &eb->bflags)) {
+ spin_unlock(&eb->refs_lock);
+ } else {
+ struct extent_io_tree *tree = eb->tree;
- spin_unlock(&eb->refs_lock);
+ spin_unlock(&eb->refs_lock);
- spin_lock(&tree->buffer_lock);
- radix_tree_delete(&tree->buffer,
- eb->start >> PAGE_CACHE_SHIFT);
- spin_unlock(&tree->buffer_lock);
+ spin_lock(&tree->buffer_lock);
+ radix_tree_delete(&tree->buffer,
+ eb->start >> PAGE_CACHE_SHIFT);
+ spin_unlock(&tree->buffer_lock);
+ }
/* Should be safe to release our pages at this point */
btrfs_release_extent_buffer_page(eb, 0);
@@ -4256,6 +4318,10 @@
spin_lock(&eb->refs_lock);
if (atomic_read(&eb->refs) == 2 &&
+ test_bit(EXTENT_BUFFER_DUMMY, &eb->bflags))
+ atomic_dec(&eb->refs);
+
+ if (atomic_read(&eb->refs) == 2 &&
test_bit(EXTENT_BUFFER_STALE, &eb->bflags) &&
!extent_buffer_under_io(eb) &&
test_and_clear_bit(EXTENT_BUFFER_TREE_REF, &eb->bflags))
diff --git a/fs/btrfs/extent_io.h b/fs/btrfs/extent_io.h
index 4d8124b..25900af 100644
--- a/fs/btrfs/extent_io.h
+++ b/fs/btrfs/extent_io.h
@@ -39,6 +39,7 @@
#define EXTENT_BUFFER_STALE 6
#define EXTENT_BUFFER_WRITEBACK 7
#define EXTENT_BUFFER_IOERR 8
+#define EXTENT_BUFFER_DUMMY 9
/* these are flags for extent_clear_unlock_delalloc */
#define EXTENT_CLEAR_UNLOCK_PAGE 0x1
@@ -264,6 +265,8 @@
struct extent_buffer *alloc_extent_buffer(struct extent_io_tree *tree,
u64 start, unsigned long len);
+struct extent_buffer *alloc_dummy_extent_buffer(u64 start, unsigned long len);
+struct extent_buffer *btrfs_clone_extent_buffer(struct extent_buffer *src);
struct extent_buffer *find_extent_buffer(struct extent_io_tree *tree,
u64 start, unsigned long len);
void free_extent_buffer(struct extent_buffer *eb);
diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index 0f8c354..24b776c 100644
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -368,7 +368,7 @@
return PTR_ERR(trans);
leaf = btrfs_alloc_free_block(trans, root, root->leafsize,
- 0, objectid, NULL, 0, 0, 0, 0);
+ 0, objectid, NULL, 0, 0, 0);
if (IS_ERR(leaf)) {
ret = PTR_ERR(leaf);
goto fail;
diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c
index 82b03af..1791c6e 100644
--- a/fs/btrfs/transaction.c
+++ b/fs/btrfs/transaction.c
@@ -56,48 +56,49 @@
static noinline int join_transaction(struct btrfs_root *root, int nofail)
{
struct btrfs_transaction *cur_trans;
+ struct btrfs_fs_info *fs_info = root->fs_info;
- spin_lock(&root->fs_info->trans_lock);
+ spin_lock(&fs_info->trans_lock);
loop:
/* The file system has been taken offline. No new transactions. */
- if (root->fs_info->fs_state & BTRFS_SUPER_FLAG_ERROR) {
- spin_unlock(&root->fs_info->trans_lock);
+ if (fs_info->fs_state & BTRFS_SUPER_FLAG_ERROR) {
+ spin_unlock(&fs_info->trans_lock);
return -EROFS;
}
- if (root->fs_info->trans_no_join) {
+ if (fs_info->trans_no_join) {
if (!nofail) {
- spin_unlock(&root->fs_info->trans_lock);
+ spin_unlock(&fs_info->trans_lock);
return -EBUSY;
}
}
- cur_trans = root->fs_info->running_transaction;
+ cur_trans = fs_info->running_transaction;
if (cur_trans) {
if (cur_trans->aborted) {
- spin_unlock(&root->fs_info->trans_lock);
+ spin_unlock(&fs_info->trans_lock);
return cur_trans->aborted;
}
atomic_inc(&cur_trans->use_count);
atomic_inc(&cur_trans->num_writers);
cur_trans->num_joined++;
- spin_unlock(&root->fs_info->trans_lock);
+ spin_unlock(&fs_info->trans_lock);
return 0;
}
- spin_unlock(&root->fs_info->trans_lock);
+ spin_unlock(&fs_info->trans_lock);
cur_trans = kmem_cache_alloc(btrfs_transaction_cachep, GFP_NOFS);
if (!cur_trans)
return -ENOMEM;
- spin_lock(&root->fs_info->trans_lock);
- if (root->fs_info->running_transaction) {
+ spin_lock(&fs_info->trans_lock);
+ if (fs_info->running_transaction) {
/*
* someone started a transaction after we unlocked. Make sure
* to redo the trans_no_join checks above
*/
kmem_cache_free(btrfs_transaction_cachep, cur_trans);
- cur_trans = root->fs_info->running_transaction;
+ cur_trans = fs_info->running_transaction;
goto loop;
}
@@ -122,20 +123,38 @@
cur_trans->delayed_refs.flushing = 0;
cur_trans->delayed_refs.run_delayed_start = 0;
cur_trans->delayed_refs.seq = 1;
+
+ /*
+ * although the tree mod log is per file system and not per transaction,
+ * the log must never go across transaction boundaries.
+ */
+ smp_mb();
+ if (!list_empty(&fs_info->tree_mod_seq_list)) {
+ printk(KERN_ERR "btrfs: tree_mod_seq_list not empty when "
+ "creating a fresh transaction\n");
+ WARN_ON(1);
+ }
+ if (!RB_EMPTY_ROOT(&fs_info->tree_mod_log)) {
+ printk(KERN_ERR "btrfs: tree_mod_log rb tree not empty when "
+ "creating a fresh transaction\n");
+ WARN_ON(1);
+ }
+ atomic_set(&fs_info->tree_mod_seq, 0);
+
init_waitqueue_head(&cur_trans->delayed_refs.seq_wait);
spin_lock_init(&cur_trans->commit_lock);
spin_lock_init(&cur_trans->delayed_refs.lock);
INIT_LIST_HEAD(&cur_trans->delayed_refs.seq_head);
INIT_LIST_HEAD(&cur_trans->pending_snapshots);
- list_add_tail(&cur_trans->list, &root->fs_info->trans_list);
+ list_add_tail(&cur_trans->list, &fs_info->trans_list);
extent_io_tree_init(&cur_trans->dirty_pages,
- root->fs_info->btree_inode->i_mapping);
- root->fs_info->generation++;
- cur_trans->transid = root->fs_info->generation;
- root->fs_info->running_transaction = cur_trans;
+ fs_info->btree_inode->i_mapping);
+ fs_info->generation++;
+ cur_trans->transid = fs_info->generation;
+ fs_info->running_transaction = cur_trans;
cur_trans->aborted = 0;
- spin_unlock(&root->fs_info->trans_lock);
+ spin_unlock(&fs_info->trans_lock);
return 0;
}
diff --git a/fs/btrfs/ulist.c b/fs/btrfs/ulist.c
index ad993bc..ab942f4 100644
--- a/fs/btrfs/ulist.c
+++ b/fs/btrfs/ulist.c
@@ -23,9 +23,9 @@
*
* ulist = ulist_alloc();
* ulist_add(ulist, root);
- * elem = NULL;
+ * ULIST_ITER_INIT(&uiter);
*
- * while ((elem = ulist_next(ulist, elem)) {
+ * while ((elem = ulist_next(ulist, &uiter)) {
* for (all child nodes n in elem)
* ulist_add(ulist, n);
* do something useful with the node;
@@ -146,11 +146,20 @@
int ulist_add(struct ulist *ulist, u64 val, unsigned long aux,
gfp_t gfp_mask)
{
+ return ulist_add_merge(ulist, val, aux, NULL, gfp_mask);
+}
+
+int ulist_add_merge(struct ulist *ulist, u64 val, unsigned long aux,
+ unsigned long *old_aux, gfp_t gfp_mask)
+{
int i;
for (i = 0; i < ulist->nnodes; ++i) {
- if (ulist->nodes[i].val == val)
+ if (ulist->nodes[i].val == val) {
+ if (old_aux)
+ *old_aux = ulist->nodes[i].aux;
return 0;
+ }
}
if (ulist->nnodes >= ulist->nodes_alloced) {
@@ -188,33 +197,26 @@
/**
* ulist_next - iterate ulist
* @ulist: ulist to iterate
- * @prev: previously returned element or %NULL to start iteration
+ * @uiter: iterator variable, initialized with ULIST_ITER_INIT(&iterator)
*
* Note: locking must be provided by the caller. In case of rwlocks only read
* locking is needed
*
- * This function is used to iterate an ulist. The iteration is started with
- * @prev = %NULL. It returns the next element from the ulist or %NULL when the
+ * This function is used to iterate an ulist.
+ * It returns the next element from the ulist or %NULL when the
* end is reached. No guarantee is made with respect to the order in which
* the elements are returned. They might neither be returned in order of
* addition nor in ascending order.
* It is allowed to call ulist_add during an enumeration. Newly added items
* are guaranteed to show up in the running enumeration.
*/
-struct ulist_node *ulist_next(struct ulist *ulist, struct ulist_node *prev)
+struct ulist_node *ulist_next(struct ulist *ulist, struct ulist_iterator *uiter)
{
- int next;
-
if (ulist->nnodes == 0)
return NULL;
-
- if (!prev)
- return &ulist->nodes[0];
-
- next = (prev - ulist->nodes) + 1;
- if (next < 0 || next >= ulist->nnodes)
+ if (uiter->i < 0 || uiter->i >= ulist->nnodes)
return NULL;
- return &ulist->nodes[next];
+ return &ulist->nodes[uiter->i++];
}
EXPORT_SYMBOL(ulist_next);
diff --git a/fs/btrfs/ulist.h b/fs/btrfs/ulist.h
index 6568c35..21bdc8e 100644
--- a/fs/btrfs/ulist.h
+++ b/fs/btrfs/ulist.h
@@ -24,6 +24,10 @@
*/
#define ULIST_SIZE 16
+struct ulist_iterator {
+ int i;
+};
+
/*
* element of the list
*/
@@ -61,7 +65,13 @@
void ulist_reinit(struct ulist *ulist);
struct ulist *ulist_alloc(gfp_t gfp_mask);
void ulist_free(struct ulist *ulist);
-int ulist_add(struct ulist *ulist, u64 val, unsigned long aux, gfp_t gfp_mask);
-struct ulist_node *ulist_next(struct ulist *ulist, struct ulist_node *prev);
+int ulist_add(struct ulist *ulist, u64 val, unsigned long aux,
+ gfp_t gfp_mask);
+int ulist_add_merge(struct ulist *ulist, u64 val, unsigned long aux,
+ unsigned long *old_aux, gfp_t gfp_mask);
+struct ulist_node *ulist_next(struct ulist *ulist,
+ struct ulist_iterator *uiter);
+
+#define ULIST_ITER_INIT(uiter) ((uiter)->i = 0)
#endif