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Commit 3fd0a558 authored by Yan, Zheng's avatar Yan, Zheng Committed by Chris Mason
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Btrfs: Metadata ENOSPC handling for balance 

This patch adds metadata ENOSPC handling for the balance code.
It is consisted by following major changes:

1. Avoid COW tree leave in the phrase of merging tree.

2. Handle interaction with snapshot creation.

3. make the backref cache can live across transactions.
Signed-off-by: default avatarYan Zheng <zheng.yan@oracle.com>
Signed-off-by: default avatarChris Mason <chris.mason@oracle.com>
parent efa56464
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Showing with 1170 additions and 754 deletions
fs/btrfs/ctree.c
View file @ 3fd0a558
......@@ -447,6 +447,9 @@ static noinline int __btrfs_cow_block(struct btrfs_trans_handle *trans,
update_ref_for_cow(trans, root, buf, cow, &last_ref);
if (root->ref_cows)
btrfs_reloc_cow_block(trans, root, buf, cow);
if (buf == root->node) {
WARN_ON(parent && parent != buf);
if (root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID ||
......
fs/btrfs/ctree.h
View file @ 3fd0a558
......@@ -2205,7 +2205,8 @@ static inline int btrfs_insert_empty_item(struct btrfs_trans_handle *trans,
int btrfs_next_leaf(struct btrfs_root *root, struct btrfs_path *path);
int btrfs_prev_leaf(struct btrfs_root *root, struct btrfs_path *path);
int btrfs_leaf_free_space(struct btrfs_root *root, struct extent_buffer *leaf);
int btrfs_drop_snapshot(struct btrfs_root *root, int update_ref);
int btrfs_drop_snapshot(struct btrfs_root *root,
struct btrfs_block_rsv *block_rsv, int update_ref);
int btrfs_drop_subtree(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
struct extent_buffer *node,
......@@ -2479,4 +2480,12 @@ int btrfs_update_reloc_root(struct btrfs_trans_handle *trans,
struct btrfs_root *root);
int btrfs_recover_relocation(struct btrfs_root *root);
int btrfs_reloc_clone_csums(struct inode *inode, u64 file_pos, u64 len);
void btrfs_reloc_cow_block(struct btrfs_trans_handle *trans,
struct btrfs_root *root, struct extent_buffer *buf,
struct extent_buffer *cow);
void btrfs_reloc_pre_snapshot(struct btrfs_trans_handle *trans,
struct btrfs_pending_snapshot *pending,
u64 *bytes_to_reserve);
void btrfs_reloc_post_snapshot(struct btrfs_trans_handle *trans,
struct btrfs_pending_snapshot *pending);
#endif
fs/btrfs/extent-tree.c
View file @ 3fd0a558
......@@ -5875,7 +5875,8 @@ static noinline int walk_up_tree(struct btrfs_trans_handle *trans,
* also make sure backrefs for the shared block and all lower level
* blocks are properly updated.
*/
int btrfs_drop_snapshot(struct btrfs_root *root, int update_ref)
int btrfs_drop_snapshot(struct btrfs_root *root,
struct btrfs_block_rsv *block_rsv, int update_ref)
{
struct btrfs_path *path;
struct btrfs_trans_handle *trans;
......@@ -5894,6 +5895,8 @@ int btrfs_drop_snapshot(struct btrfs_root *root, int update_ref)
BUG_ON(!wc);
trans = btrfs_start_transaction(tree_root, 0);
if (block_rsv)
trans->block_rsv = block_rsv;
if (btrfs_disk_key_objectid(&root_item->drop_progress) == 0) {
level = btrfs_header_level(root->node);
......@@ -5981,24 +5984,16 @@ int btrfs_drop_snapshot(struct btrfs_root *root, int update_ref)
}
BUG_ON(wc->level == 0);
if (trans->transaction->in_commit ||
trans->transaction->delayed_refs.flushing) {
if (btrfs_should_end_transaction(trans, tree_root)) {
ret = btrfs_update_root(trans, tree_root,
&root->root_key,
root_item);
BUG_ON(ret);
btrfs_end_transaction(trans, tree_root);
btrfs_end_transaction_throttle(trans, tree_root);
trans = btrfs_start_transaction(tree_root, 0);
if (IS_ERR(trans))
return PTR_ERR(trans);
} else {
unsigned long update;
update = trans->delayed_ref_updates;
trans->delayed_ref_updates = 0;
if (update)
btrfs_run_delayed_refs(trans, tree_root,
update);
if (block_rsv)
trans->block_rsv = block_rsv;
}
}
btrfs_release_path(root, path);
......@@ -6026,7 +6021,7 @@ int btrfs_drop_snapshot(struct btrfs_root *root, int update_ref)
kfree(root);
}
out:
btrfs_end_transaction(trans, tree_root);
btrfs_end_transaction_throttle(trans, tree_root);
kfree(wc);
btrfs_free_path(path);
return err;
......
fs/btrfs/relocation.c
View file @ 3fd0a558
......@@ -44,8 +44,12 @@ struct tree_entry {
struct backref_node {
struct rb_node rb_node;
u64 bytenr;
/* objectid tree block owner */
u64 new_bytenr;
/* objectid of tree block owner, can be not uptodate */
u64 owner;
/* link to pending, changed or detached list */
struct list_head list;
/* list of upper level blocks reference this block */
struct list_head upper;
/* list of child blocks in the cache */
......@@ -56,9 +60,9 @@ struct backref_node {
struct extent_buffer *eb;
/* level of tree block */
unsigned int level:8;
/* 1 if the block is root of old snapshot */
unsigned int old_root:1;
/* 1 if no child blocks in the cache */
/* is the block in non-reference counted tree */
unsigned int cowonly:1;
/* 1 if no child node in the cache */
unsigned int lowest:1;
/* is the extent buffer locked */
unsigned int locked:1;
......@@ -66,6 +70,16 @@ struct backref_node {
unsigned int processed:1;
/* have backrefs of this block been checked */
unsigned int checked:1;
/*
* 1 if corresponding block has been cowed but some upper
* level block pointers may not point to the new location
*/
unsigned int pending:1;
/*
* 1 if the backref node isn't connected to any other
* backref node.
*/
unsigned int detached:1;
};
/*
......@@ -74,7 +88,6 @@ struct backref_node {
struct backref_edge {
struct list_head list[2];
struct backref_node *node[2];
u64 blockptr;
};
#define LOWER 0
......@@ -83,9 +96,25 @@ struct backref_edge {
struct backref_cache {
/* red black tree of all backref nodes in the cache */
struct rb_root rb_root;
/* list of backref nodes with no child block in the cache */
/* for passing backref nodes to btrfs_reloc_cow_block */
struct backref_node *path[BTRFS_MAX_LEVEL];
/*
* list of blocks that have been cowed but some block
* pointers in upper level blocks may not reflect the
* new location
*/
struct list_head pending[BTRFS_MAX_LEVEL];
spinlock_t lock;
/* list of backref nodes with no child node */
struct list_head leaves;
/* list of blocks that have been cowed in current transaction */
struct list_head changed;
/* list of detached backref node. */
struct list_head detached;
u64 last_trans;
int nr_nodes;
int nr_edges;
};
/*
......@@ -113,15 +142,6 @@ struct tree_block {
unsigned int key_ready:1;
};
/* inode vector */
#define INODEVEC_SIZE 16
struct inodevec {
struct list_head list;
struct inode *inode[INODEVEC_SIZE];
int nr;
};
#define MAX_EXTENTS 128
struct file_extent_cluster {
......@@ -138,36 +158,43 @@ struct reloc_control {
struct btrfs_root *extent_root;
/* inode for moving data */
struct inode *data_inode;
struct btrfs_workers workers;
struct btrfs_block_rsv *block_rsv;
struct backref_cache backref_cache;
struct file_extent_cluster cluster;
/* tree blocks have been processed */
struct extent_io_tree processed_blocks;
/* map start of tree root to corresponding reloc tree */
struct mapping_tree reloc_root_tree;
/* list of reloc trees */
struct list_head reloc_roots;
/* size of metadata reservation for merging reloc trees */
u64 merging_rsv_size;
/* size of relocated tree nodes */
u64 nodes_relocated;
u64 search_start;
u64 extents_found;
u64 extents_skipped;
int stage;
int create_reloc_root;
int block_rsv_retries;
unsigned int stage:8;
unsigned int create_reloc_tree:1;
unsigned int merge_reloc_tree:1;
unsigned int found_file_extent:1;
unsigned int found_old_snapshot:1;
unsigned int commit_transaction:1;
};
/* stages of data relocation */
#define MOVE_DATA_EXTENTS 0
#define UPDATE_DATA_PTRS 1
/*
* merge reloc tree to corresponding fs tree in worker threads
*/
struct async_merge {
struct btrfs_work work;
struct reloc_control *rc;
struct btrfs_root *root;
struct completion *done;
atomic_t *num_pending;
};
static void remove_backref_node(struct backref_cache *cache,
struct backref_node *node);
static void __mark_block_processed(struct reloc_control *rc,
struct backref_node *node);
static void mapping_tree_init(struct mapping_tree *tree)
{
......@@ -181,15 +208,80 @@ static void backref_cache_init(struct backref_cache *cache)
cache->rb_root = RB_ROOT;
for (i = 0; i < BTRFS_MAX_LEVEL; i++)
INIT_LIST_HEAD(&cache->pending[i]);
spin_lock_init(&cache->lock);
INIT_LIST_HEAD(&cache->changed);
INIT_LIST_HEAD(&cache->detached);
INIT_LIST_HEAD(&cache->leaves);
}
static void backref_cache_cleanup(struct backref_cache *cache)
{
struct backref_node *node;
int i;
while (!list_empty(&cache->detached)) {
node = list_entry(cache->detached.next,
struct backref_node, list);
remove_backref_node(cache, node);
}
while (!list_empty(&cache->leaves)) {
node = list_entry(cache->leaves.next,
struct backref_node, lower);
remove_backref_node(cache, node);
}
cache->last_trans = 0;
for (i = 0; i < BTRFS_MAX_LEVEL; i++)
BUG_ON(!list_empty(&cache->pending[i]));
BUG_ON(!list_empty(&cache->changed));
BUG_ON(!list_empty(&cache->detached));
BUG_ON(!RB_EMPTY_ROOT(&cache->rb_root));
BUG_ON(cache->nr_nodes);
BUG_ON(cache->nr_edges);
}
static void backref_node_init(struct backref_node *node)
static struct backref_node *alloc_backref_node(struct backref_cache *cache)
{
memset(node, 0, sizeof(*node));
struct backref_node *node;
node = kzalloc(sizeof(*node), GFP_NOFS);
if (node) {
INIT_LIST_HEAD(&node->list);
INIT_LIST_HEAD(&node->upper);
INIT_LIST_HEAD(&node->lower);
RB_CLEAR_NODE(&node->rb_node);
cache->nr_nodes++;
}
return node;
}
static void free_backref_node(struct backref_cache *cache,
struct backref_node *node)
{
if (node) {
cache->nr_nodes--;
kfree(node);
}
}
static struct backref_edge *alloc_backref_edge(struct backref_cache *cache)
{
struct backref_edge *edge;
edge = kzalloc(sizeof(*edge), GFP_NOFS);
if (edge)
cache->nr_edges++;
return edge;
}
static void free_backref_edge(struct backref_cache *cache,
struct backref_edge *edge)
{
if (edge) {
cache->nr_edges--;
kfree(edge);
}
}
static struct rb_node *tree_insert(struct rb_root *root, u64 bytenr,
......@@ -250,6 +342,7 @@ static struct backref_node *walk_up_backref(struct backref_node *node,
edges[idx++] = edge;
node = edge->node[UPPER];
}
BUG_ON(node->detached);
*index = idx;
return node;
}
......@@ -281,13 +374,18 @@ static struct backref_node *walk_down_backref(struct backref_edge *edges[],
return NULL;
}
static void drop_node_buffer(struct backref_node *node)
static void unlock_node_buffer(struct backref_node *node)
{
if (node->eb) {
if (node->locked) {
btrfs_tree_unlock(node->eb);
node->locked = 0;
}
}
static void drop_node_buffer(struct backref_node *node)
{
if (node->eb) {
unlock_node_buffer(node);
free_extent_buffer(node->eb);
node->eb = NULL;
}
......@@ -296,14 +394,14 @@ static void drop_node_buffer(struct backref_node *node)
static void drop_backref_node(struct backref_cache *tree,
struct backref_node *node)
{
BUG_ON(!node->lowest);
BUG_ON(!list_empty(&node->upper));
drop_node_buffer(node);
list_del(&node->list);
list_del(&node->lower);
if (!RB_EMPTY_NODE(&node->rb_node))
rb_erase(&node->rb_node, &tree->rb_root);
kfree(node);
free_backref_node(tree, node);
}
/*
......@@ -318,27 +416,121 @@ static void remove_backref_node(struct backref_cache *cache,
if (!node)
return;
BUG_ON(!node->lowest);
BUG_ON(!node->lowest && !node->detached);
while (!list_empty(&node->upper)) {
edge = list_entry(node->upper.next, struct backref_edge,
list[LOWER]);
upper = edge->node[UPPER];
list_del(&edge->list[LOWER]);
list_del(&edge->list[UPPER]);
kfree(edge);
free_backref_edge(cache, edge);
if (RB_EMPTY_NODE(&upper->rb_node)) {
BUG_ON(!list_empty(&node->upper));
drop_backref_node(cache, node);
node = upper;
node->lowest = 1;
continue;
}
/*
* add the node to pending list if no other
* add the node to leaf node list if no other
* child block cached.
*/
if (list_empty(&upper->lower)) {
list_add_tail(&upper->lower,
&cache->pending[upper->level]);
list_add_tail(&upper->lower, &cache->leaves);
upper->lowest = 1;
}
}
drop_backref_node(cache, node);
}
static void update_backref_node(struct backref_cache *cache,
struct backref_node *node, u64 bytenr)
{
struct rb_node *rb_node;
rb_erase(&node->rb_node, &cache->rb_root);
node->bytenr = bytenr;
rb_node = tree_insert(&cache->rb_root, node->bytenr, &node->rb_node);
BUG_ON(rb_node);
}
/*
* update backref cache after a transaction commit
*/
static int update_backref_cache(struct btrfs_trans_handle *trans,
struct backref_cache *cache)
{
struct backref_node *node;
int level = 0;
if (cache->last_trans == 0) {
cache->last_trans = trans->transid;
return 0;
}
if (cache->last_trans == trans->transid)
return 0;
/*
* detached nodes are used to avoid unnecessary backref
* lookup. transaction commit changes the extent tree.
* so the detached nodes are no longer useful.
*/
while (!list_empty(&cache->detached)) {
node = list_entry(cache->detached.next,
struct backref_node, list);
remove_backref_node(cache, node);
}
while (!list_empty(&cache->changed)) {
node = list_entry(cache->changed.next,
struct backref_node, list);
list_del_init(&node->list);
BUG_ON(node->pending);
update_backref_node(cache, node, node->new_bytenr);
}
/*
* some nodes can be left in the pending list if there were
* errors during processing the pending nodes.
*/
for (level = 0; level < BTRFS_MAX_LEVEL; level++) {
list_for_each_entry(node, &cache->pending[level], list) {
BUG_ON(!node->pending);
if (node->bytenr == node->new_bytenr)
continue;
update_backref_node(cache, node, node->new_bytenr);
}
}
cache->last_trans = 0;
return 1;
}
static int should_ignore_root(struct btrfs_root *root)
{
struct btrfs_root *reloc_root;
if (!root->ref_cows)
return 0;
reloc_root = root->reloc_root;
if (!reloc_root)
return 0;
if (btrfs_root_last_snapshot(&reloc_root->root_item) ==
root->fs_info->running_transaction->transid - 1)
return 0;
/*
* if there is reloc tree and it was created in previous
* transaction backref lookup can find the reloc tree,
* so backref node for the fs tree root is useless for
* relocation.
*/
return 1;
}
/*
* find reloc tree by address of tree root
*/
......@@ -453,11 +645,12 @@ int find_inline_backref(struct extent_buffer *leaf, int slot,
* for all upper level blocks that directly/indirectly reference the
* block are also cached.
*/
static struct backref_node *build_backref_tree(struct reloc_control *rc,
struct backref_cache *cache,
static noinline_for_stack
struct backref_node *build_backref_tree(struct reloc_control *rc,
struct btrfs_key *node_key,
int level, u64 bytenr)
{
struct backref_cache *cache = &rc->backref_cache;
struct btrfs_path *path1;
struct btrfs_path *path2;
struct extent_buffer *eb;
......@@ -473,6 +666,8 @@ static struct backref_node *build_backref_tree(struct reloc_control *rc,
unsigned long end;
unsigned long ptr;
LIST_HEAD(list);
LIST_HEAD(useless);
int cowonly;
int ret;
int err = 0;
......@@ -483,15 +678,13 @@ static struct backref_node *build_backref_tree(struct reloc_control *rc,
goto out;
}
node = kmalloc(sizeof(*node), GFP_NOFS);
node = alloc_backref_node(cache);
if (!node) {
err = -ENOMEM;
goto out;
}
backref_node_init(node);
node->bytenr = bytenr;
node->owner = 0;
node->level = level;
node->lowest = 1;
cur = node;
......@@ -587,18 +780,21 @@ static struct backref_node *build_backref_tree(struct reloc_control *rc,
#ifdef BTRFS_COMPAT_EXTENT_TREE_V0
if (key.type == BTRFS_SHARED_BLOCK_REF_KEY ||
key.type == BTRFS_EXTENT_REF_V0_KEY) {
if (key.objectid == key.offset &&
key.type == BTRFS_EXTENT_REF_V0_KEY) {
if (key.type == BTRFS_EXTENT_REF_V0_KEY) {
struct btrfs_extent_ref_v0 *ref0;
ref0 = btrfs_item_ptr(eb, path1->slots[0],
struct btrfs_extent_ref_v0);
root = find_tree_root(rc, eb, ref0);
if (root)
if (!root->ref_cows)
cur->cowonly = 1;
if (key.objectid == key.offset) {
if (root && !should_ignore_root(root))
cur->root = root;
else
cur->old_root = 1;
list_add(&cur->list, &useless);
break;
}
}
#else
BUG_ON(key.type == BTRFS_EXTENT_REF_V0_KEY);
if (key.type == BTRFS_SHARED_BLOCK_REF_KEY) {
......@@ -614,22 +810,20 @@ static struct backref_node *build_backref_tree(struct reloc_control *rc,
break;
}
edge = kzalloc(sizeof(*edge), GFP_NOFS);
edge = alloc_backref_edge(cache);
if (!edge) {
err = -ENOMEM;
goto out;
}
rb_node = tree_search(&cache->rb_root, key.offset);
if (!rb_node) {
upper = kmalloc(sizeof(*upper), GFP_NOFS);
upper = alloc_backref_node(cache);
if (!upper) {
kfree(edge);
free_backref_edge(cache, edge);
err = -ENOMEM;
goto out;
}
backref_node_init(upper);
upper->bytenr = key.offset;
upper->owner = 0;
upper->level = cur->level + 1;
/*
* backrefs for the upper level block isn't
......@@ -639,11 +833,12 @@ static struct backref_node *build_backref_tree(struct reloc_control *rc,
} else {
upper = rb_entry(rb_node, struct backref_node,
rb_node);
BUG_ON(!upper->checked);
INIT_LIST_HEAD(&edge->list[UPPER]);
}
list_add(&edge->list[LOWER], &cur->upper);
edge->node[UPPER] = upper;
list_add_tail(&edge->list[LOWER], &cur->upper);
edge->node[LOWER] = cur;
edge->node[UPPER] = upper;
goto next;
} else if (key.type != BTRFS_TREE_BLOCK_REF_KEY) {
......@@ -657,10 +852,16 @@ static struct backref_node *build_backref_tree(struct reloc_control *rc,
goto out;
}
if (!root->ref_cows)
cur->cowonly = 1;
if (btrfs_root_level(&root->root_item) == cur->level) {
/* tree root */
BUG_ON(btrfs_root_bytenr(&root->root_item) !=
cur->bytenr);
if (should_ignore_root(root))
list_add(&cur->list, &useless);
else
cur->root = root;
break;
}
......@@ -692,11 +893,14 @@ static struct backref_node *build_backref_tree(struct reloc_control *rc,
if (!path2->nodes[level]) {
BUG_ON(btrfs_root_bytenr(&root->root_item) !=
lower->bytenr);
if (should_ignore_root(root))
list_add(&lower->list, &useless);
else
lower->root = root;
break;
}
edge = kzalloc(sizeof(*edge), GFP_NOFS);
edge = alloc_backref_edge(cache);
if (!edge) {
err = -ENOMEM;
goto out;
......@@ -705,16 +909,17 @@ static struct backref_node *build_backref_tree(struct reloc_control *rc,
eb = path2->nodes[level];
rb_node = tree_search(&cache->rb_root, eb->start);
if (!rb_node) {
upper = kmalloc(sizeof(*upper), GFP_NOFS);
upper = alloc_backref_node(cache);
if (!upper) {
kfree(edge);
free_backref_edge(cache, edge);
err = -ENOMEM;
goto out;
}
backref_node_init(upper);
upper->bytenr = eb->start;
upper->owner = btrfs_header_owner(eb);
upper->level = lower->level + 1;
if (!root->ref_cows)
upper->cowonly = 1;
/*
* if we know the block isn't shared
......@@ -744,10 +949,12 @@ static struct backref_node *build_backref_tree(struct reloc_control *rc,
rb_node);
BUG_ON(!upper->checked);
INIT_LIST_HEAD(&edge->list[UPPER]);
if (!upper->owner)
upper->owner = btrfs_header_owner(eb);
}
list_add_tail(&edge->list[LOWER], &lower->upper);
edge->node[UPPER] = upper;
edge->node[LOWER] = lower;
edge->node[UPPER] = upper;
if (rb_node)
break;
......@@ -785,8 +992,13 @@ static struct backref_node *build_backref_tree(struct reloc_control *rc,
* into the cache.
*/
BUG_ON(!node->checked);
rb_node = tree_insert(&cache->rb_root, node->bytenr, &node->rb_node);
cowonly = node->cowonly;
if (!cowonly) {
rb_node = tree_insert(&cache->rb_root, node->bytenr,
&node->rb_node);
BUG_ON(rb_node);
list_add_tail(&node->lower, &cache->leaves);
}
list_for_each_entry(edge, &node->upper, list[LOWER])
list_add_tail(&edge->list[UPPER], &list);
......@@ -795,6 +1007,14 @@ static struct backref_node *build_backref_tree(struct reloc_control *rc,
edge = list_entry(list.next, struct backref_edge, list[UPPER]);
list_del_init(&edge->list[UPPER]);
upper = edge->node[UPPER];
if (upper->detached) {
list_del(&edge->list[LOWER]);
lower = edge->node[LOWER];
free_backref_edge(cache, edge);
if (list_empty(&lower->upper))
list_add(&lower->list, &useless);
continue;
}
if (!RB_EMPTY_NODE(&upper->rb_node)) {
if (upper->lowest) {
......@@ -807,25 +1027,69 @@ static struct backref_node *build_backref_tree(struct reloc_control *rc,
}
BUG_ON(!upper->checked);
BUG_ON(cowonly != upper->cowonly);
if (!cowonly) {
rb_node = tree_insert(&cache->rb_root, upper->bytenr,
&upper->rb_node);
BUG_ON(rb_node);
}
list_add_tail(&edge->list[UPPER], &upper->lower);
list_for_each_entry(edge, &upper->upper, list[LOWER])
list_add_tail(&edge->list[UPPER], &list);
}
/*
* process useless backref nodes. backref nodes for tree leaves
* are deleted from the cache. backref nodes for upper level
* tree blocks are left in the cache to avoid unnecessary backref
* lookup.
*/
while (!list_empty(&useless)) {
upper = list_entry(useless.next, struct backref_node, list);
list_del_init(&upper->list);
BUG_ON(!list_empty(&upper->upper));
if (upper == node)
node = NULL;
if (upper->lowest) {
list_del_init(&upper->lower);
upper->lowest = 0;
}
while (!list_empty(&upper->lower)) {
edge = list_entry(upper->lower.next,
struct backref_edge, list[UPPER]);
list_del(&edge->list[UPPER]);
list_del(&edge->list[LOWER]);
lower = edge->node[LOWER];
free_backref_edge(cache, edge);
if (list_empty(&lower->upper))
list_add(&lower->list, &useless);
}
__mark_block_processed(rc, upper);
if (upper->level > 0) {
list_add(&upper->list, &cache->detached);
upper->detached = 1;
} else {
rb_erase(&upper->rb_node, &cache->rb_root);
free_backref_node(cache, upper);
}
}
out:
btrfs_free_path(path1);
btrfs_free_path(path2);
if (err) {
INIT_LIST_HEAD(&list);
while (!list_empty(&useless)) {
lower = list_entry(useless.next,
struct backref_node, upper);
list_del_init(&lower->upper);
}
upper = node;
INIT_LIST_HEAD(&list);
while (upper) {
if (RB_EMPTY_NODE(&upper->rb_node)) {
list_splice_tail(&upper->upper, &list);
kfree(upper);
free_backref_node(cache, upper);
}
if (list_empty(&list))
......@@ -833,14 +1097,103 @@ static struct backref_node *build_backref_tree(struct reloc_control *rc,
edge = list_entry(list.next, struct backref_edge,
list[LOWER]);
list_del(&edge->list[LOWER]);
upper = edge->node[UPPER];
kfree(edge);
free_backref_edge(cache, edge);
}
return ERR_PTR(err);
}
BUG_ON(node && node->detached);
return node;
}
/*
* helper to add backref node for the newly created snapshot.
* the backref node is created by cloning backref node that
* corresponds to root of source tree
*/
static int clone_backref_node(struct btrfs_trans_handle *trans,
struct reloc_control *rc,
struct btrfs_root *src,
struct btrfs_root *dest)
{
struct btrfs_root *reloc_root = src->reloc_root;
struct backref_cache *cache = &rc->backref_cache;
struct backref_node *node = NULL;
struct backref_node *new_node;
struct backref_edge *edge;
struct backref_edge *new_edge;
struct rb_node *rb_node;
if (cache->last_trans > 0)
update_backref_cache(trans, cache);
rb_node = tree_search(&cache->rb_root, src->commit_root->start);
if (rb_node) {
node = rb_entry(rb_node, struct backref_node, rb_node);
if (node->detached)
node = NULL;
else
BUG_ON(node->new_bytenr != reloc_root->node->start);
}
if (!node) {
rb_node = tree_search(&cache->rb_root,
reloc_root->commit_root->start);
if (rb_node) {
node = rb_entry(rb_node, struct backref_node,
rb_node);
BUG_ON(node->detached);
}
}
if (!node)
return 0;
new_node = alloc_backref_node(cache);
if (!new_node)
return -ENOMEM;
new_node->bytenr = dest->node->start;
new_node->level = node->level;
new_node->lowest = node->lowest;
new_node->root = dest;
if (!node->lowest) {
list_for_each_entry(edge, &node->lower, list[UPPER]) {
new_edge = alloc_backref_edge(cache);
if (!new_edge)
goto fail;
new_edge->node[UPPER] = new_node;
new_edge->node[LOWER] = edge->node[LOWER];
list_add_tail(&new_edge->list[UPPER],
&new_node->lower);
}
}
rb_node = tree_insert(&cache->rb_root, new_node->bytenr,
&new_node->rb_node);
BUG_ON(rb_node);
if (!new_node->lowest) {
list_for_each_entry(new_edge, &new_node->lower, list[UPPER]) {
list_add_tail(&new_edge->list[LOWER],
&new_edge->node[LOWER]->upper);
}
}
return 0;
fail:
while (!list_empty(&new_node->lower)) {
new_edge = list_entry(new_node->lower.next,
struct backref_edge, list[UPPER]);
list_del(&new_edge->list[UPPER]);
free_backref_edge(cache, new_edge);
}
free_backref_node(cache, new_node);
return -ENOMEM;
}
/*
* helper to add 'address of tree root -> reloc tree' mapping
*/
......@@ -901,12 +1254,8 @@ static int __update_reloc_root(struct btrfs_root *root, int del)
return 0;
}
/*
* create reloc tree for a given fs tree. reloc tree is just a
* snapshot of the fs tree with special root objectid.
*/
int btrfs_init_reloc_root(struct btrfs_trans_handle *trans,
struct btrfs_root *root)
static struct btrfs_root *create_reloc_root(struct btrfs_trans_handle *trans,
struct btrfs_root *root, u64 objectid)
{
struct btrfs_root *reloc_root;
struct extent_buffer *eb;
......@@ -914,36 +1263,45 @@ int btrfs_init_reloc_root(struct btrfs_trans_handle *trans,
struct btrfs_key root_key;
int ret;
if (root->reloc_root) {
reloc_root = root->reloc_root;
reloc_root->last_trans = trans->transid;
return 0;
}
if (!root->fs_info->reloc_ctl ||
!root->fs_info->reloc_ctl->create_reloc_root ||
root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID)
return 0;
root_item = kmalloc(sizeof(*root_item), GFP_NOFS);
BUG_ON(!root_item);
root_key.objectid = BTRFS_TREE_RELOC_OBJECTID;
root_key.type = BTRFS_ROOT_ITEM_KEY;
root_key.offset = root->root_key.objectid;
root_key.offset = objectid;
if (root->root_key.objectid == objectid) {
/* called by btrfs_init_reloc_root */
ret = btrfs_copy_root(trans, root, root->commit_root, &eb,
BTRFS_TREE_RELOC_OBJECTID);
BUG_ON(ret);
btrfs_set_root_last_snapshot(&root->root_item, trans->transid - 1);
btrfs_set_root_last_snapshot(&root->root_item,
trans->transid - 1);
} else {
/*
* called by btrfs_reloc_post_snapshot_hook.
* the source tree is a reloc tree, all tree blocks
* modified after it was created have RELOC flag
* set in their headers. so it's OK to not update
* the 'last_snapshot'.
*/
ret = btrfs_copy_root(trans, root, root->node, &eb,
BTRFS_TREE_RELOC_OBJECTID);
BUG_ON(ret);
}
memcpy(root_item, &root->root_item, sizeof(*root_item));
btrfs_set_root_refs(root_item, 1);
btrfs_set_root_bytenr(root_item, eb->start);
btrfs_set_root_level(root_item, btrfs_header_level(eb));
btrfs_set_root_generation(root_item, trans->transid);
memset(&root_item->drop_progress, 0, sizeof(struct btrfs_disk_key));
if (root->root_key.objectid == objectid) {
btrfs_set_root_refs(root_item, 0);
memset(&root_item->drop_progress, 0,
sizeof(struct btrfs_disk_key));
root_item->drop_level = 0;
}
btrfs_tree_unlock(eb);
free_extent_buffer(eb);
......@@ -957,30 +1315,62 @@ int btrfs_init_reloc_root(struct btrfs_trans_handle *trans,
&root_key);
BUG_ON(IS_ERR(reloc_root));
reloc_root->last_trans = trans->transid;
__add_reloc_root(reloc_root);
root->reloc_root = reloc_root;
return 0;
return reloc_root;
}
/*
* update root item of reloc tree
* create reloc tree for a given fs tree. reloc tree is just a
* snapshot of the fs tree with special root objectid.
*/
int btrfs_update_reloc_root(struct btrfs_trans_handle *trans,
int btrfs_init_reloc_root(struct btrfs_trans_handle *trans,
struct btrfs_root *root)
{
struct btrfs_root *reloc_root;
struct btrfs_root_item *root_item;
int del = 0;
int ret;
if (!root->reloc_root)
return 0;
struct reloc_control *rc = root->fs_info->reloc_ctl;
int clear_rsv = 0;
if (root->reloc_root) {
reloc_root = root->reloc_root;
reloc_root->last_trans = trans->transid;
return 0;
}
if (!rc || !rc->create_reloc_tree ||
root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID)
return 0;
if (!trans->block_rsv) {
trans->block_rsv = rc->block_rsv;
clear_rsv = 1;
}
reloc_root = create_reloc_root(trans, root, root->root_key.objectid);
if (clear_rsv)
trans->block_rsv = NULL;
__add_reloc_root(reloc_root);
root->reloc_root = reloc_root;
return 0;
}
/*
* update root item of reloc tree
*/
int btrfs_update_reloc_root(struct btrfs_trans_handle *trans,
struct btrfs_root *root)
{
struct btrfs_root *reloc_root;
struct btrfs_root_item *root_item;
int del = 0;
int ret;
if (!root->reloc_root)
return 0;
reloc_root = root->reloc_root;
root_item = &reloc_root->root_item;
if (btrfs_root_refs(root_item) == 0) {
if (root->fs_info->reloc_ctl->merge_reloc_tree &&
btrfs_root_refs(root_item) == 0) {
root->reloc_root = NULL;
del = 1;
}
......@@ -1102,7 +1492,6 @@ static int get_new_location(struct inode *reloc_inode, u64 *new_bytenr,
goto out;
}
if (new_bytenr)
*new_bytenr = btrfs_file_extent_disk_bytenr(leaf, fi);
ret = 0;
out:
......@@ -1114,19 +1503,18 @@ static int get_new_location(struct inode *reloc_inode, u64 *new_bytenr,
* update file extent items in the tree leaf to point to
* the new locations.
*/
static int replace_file_extents(struct btrfs_trans_handle *trans,
static noinline_for_stack
int replace_file_extents(struct btrfs_trans_handle *trans,
struct reloc_control *rc,
struct btrfs_root *root,
struct extent_buffer *leaf,
struct list_head *inode_list)
struct extent_buffer *leaf)
{
struct btrfs_key key;
struct btrfs_file_extent_item *fi;
struct inode *inode = NULL;
struct inodevec *ivec = NULL;
u64 parent;
u64 bytenr;
u64 new_bytenr;
u64 new_bytenr = 0;
u64 num_bytes;
u64 end;
u32 nritems;
......@@ -1166,21 +1554,12 @@ static int replace_file_extents(struct btrfs_trans_handle *trans,
* to complete and drop the extent cache
*/
if (root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID) {
if (!ivec || ivec->nr == INODEVEC_SIZE) {
ivec = kmalloc(sizeof(*ivec), GFP_NOFS);
BUG_ON(!ivec);
ivec->nr = 0;
list_add_tail(&ivec->list, inode_list);
}
if (first) {
inode = find_next_inode(root, key.objectid);
if (inode)
ivec->inode[ivec->nr++] = inode;
first = 0;
} else if (inode && inode->i_ino < key.objectid) {
btrfs_add_delayed_iput(inode);
inode = find_next_inode(root, key.objectid);
if (inode)
ivec->inode[ivec->nr++] = inode;
}
if (inode && inode->i_ino == key.objectid) {
end = key.offset +
......@@ -1204,8 +1583,10 @@ static int replace_file_extents(struct btrfs_trans_handle *trans,
ret = get_new_location(rc->data_inode, &new_bytenr,
bytenr, num_bytes);
if (ret > 0)
if (ret > 0) {
WARN_ON(1);
continue;
}
BUG_ON(ret < 0);
btrfs_set_file_extent_disk_bytenr(leaf, fi, new_bytenr);
......@@ -1225,6 +1606,8 @@ static int replace_file_extents(struct btrfs_trans_handle *trans,
}
if (dirty)
btrfs_mark_buffer_dirty(leaf);
if (inode)
btrfs_add_delayed_iput(inode);
return 0;
}
......@@ -1248,10 +1631,10 @@ int memcmp_node_keys(struct extent_buffer *eb, int slot,
* if no block got replaced, 0 is returned. if there are other
* errors, a negative error number is returned.
*/
static int replace_path(struct btrfs_trans_handle *trans,
static noinline_for_stack
int replace_path(struct btrfs_trans_handle *trans,
struct btrfs_root *dest, struct btrfs_root *src,
struct btrfs_path *path, struct btrfs_key *next_key,
struct extent_buffer **leaf,
int lowest_level, int max_level)
{
struct extent_buffer *eb;
......@@ -1263,16 +1646,16 @@ static int replace_path(struct btrfs_trans_handle *trans,
u64 new_ptr_gen;
u64 last_snapshot;
u32 blocksize;
int cow = 0;
int level;
int ret;
int slot;
BUG_ON(src->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID);
BUG_ON(dest->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID);
BUG_ON(lowest_level > 1 && leaf);
last_snapshot = btrfs_root_last_snapshot(&src->root_item);
again:
slot = path->slots[lowest_level];
btrfs_node_key_to_cpu(path->nodes[lowest_level], &key, slot);
......@@ -1286,8 +1669,10 @@ static int replace_path(struct btrfs_trans_handle *trans,
return 0;
}
if (cow) {
ret = btrfs_cow_block(trans, dest, eb, NULL, 0, &eb);
BUG_ON(ret);
}
btrfs_set_lock_blocking(eb);
if (next_key) {
......@@ -1331,7 +1716,7 @@ static int replace_path(struct btrfs_trans_handle *trans,
if (new_bytenr == 0 || old_ptr_gen > last_snapshot ||
memcmp_node_keys(parent, slot, path, level)) {
if (level <= lowest_level && !leaf) {
if (level <= lowest_level) {
ret = 0;
break;
}
......@@ -1339,16 +1724,12 @@ static int replace_path(struct btrfs_trans_handle *trans,
eb = read_tree_block(dest, old_bytenr, blocksize,
old_ptr_gen);
btrfs_tree_lock(eb);
if (cow) {
ret = btrfs_cow_block(trans, dest, eb, parent,
slot, &eb);
BUG_ON(ret);
btrfs_set_lock_blocking(eb);
if (level <= lowest_level) {
*leaf = eb;
ret = 0;
break;
}
btrfs_set_lock_blocking(eb);
btrfs_tree_unlock(parent);
free_extent_buffer(parent);
......@@ -1357,6 +1738,13 @@ static int replace_path(struct btrfs_trans_handle *trans,
continue;
}
if (!cow) {
btrfs_tree_unlock(parent);
free_extent_buffer(parent);
cow = 1;
goto again;
}
btrfs_node_key_to_cpu(path->nodes[level], &key,
path->slots[level]);
btrfs_release_path(src, path);
......@@ -1562,20 +1950,6 @@ static int invalidate_extent_cache(struct btrfs_root *root,
return 0;
}
static void put_inodes(struct list_head *list)
{
struct inodevec *ivec;
while (!list_empty(list)) {
ivec = list_entry(list->next, struct inodevec, list);
list_del(&ivec->list);
while (ivec->nr > 0) {
ivec->nr--;
iput(ivec->inode[ivec->nr]);
}
kfree(ivec);
}
}
static int find_next_key(struct btrfs_path *path, int level,
struct btrfs_key *key)
......@@ -1608,13 +1982,14 @@ static noinline_for_stack int merge_reloc_root(struct reloc_control *rc,
struct btrfs_root *reloc_root;
struct btrfs_root_item *root_item;
struct btrfs_path *path;
struct extent_buffer *leaf = NULL;
struct extent_buffer *leaf;
unsigned long nr;
int level;
int max_level;
int replaced = 0;
int ret;
int err = 0;
u32 min_reserved;
path = btrfs_alloc_path();
if (!path)
......@@ -1648,34 +2023,23 @@ static noinline_for_stack int merge_reloc_root(struct reloc_control *rc,
btrfs_unlock_up_safe(path, 0);
}
if (level == 0 && rc->stage == UPDATE_DATA_PTRS) {
trans = btrfs_start_transaction(root, 0);
leaf = path->nodes[0];
btrfs_item_key_to_cpu(leaf, &key, 0);
btrfs_release_path(reloc_root, path);
min_reserved = root->nodesize * (BTRFS_MAX_LEVEL - 1) * 2;
memset(&next_key, 0, sizeof(next_key));
ret = btrfs_search_slot(trans, root, &key, path, 0, 1);
if (ret < 0) {
err = ret;
goto out;
}
while (1) {
trans = btrfs_start_transaction(root, 0);
trans->block_rsv = rc->block_rsv;
leaf = path->nodes[0];
btrfs_unlock_up_safe(path, 1);
ret = replace_file_extents(trans, rc, root, leaf,
&inode_list);
if (ret < 0)
err = ret;
goto out;
ret = btrfs_block_rsv_check(trans, root, rc->block_rsv,
min_reserved, 0);
if (ret) {
BUG_ON(ret != -EAGAIN);
ret = btrfs_commit_transaction(trans, root);
BUG_ON(ret);
continue;
}
memset(&next_key, 0, sizeof(next_key));
while (1) {
leaf = NULL;
replaced = 0;
trans = btrfs_start_transaction(root, 0);
max_level = level;
ret = walk_down_reloc_tree(reloc_root, path, &level);
......@@ -1689,14 +2053,9 @@ static noinline_for_stack int merge_reloc_root(struct reloc_control *rc,
if (!find_next_key(path, level, &key) &&
btrfs_comp_cpu_keys(&next_key, &key) >= 0) {
ret = 0;
} else if (level == 1 && rc->stage == UPDATE_DATA_PTRS) {
ret = replace_path(trans, root, reloc_root,
path, &next_key, &leaf,
level, max_level);
} else {
ret = replace_path(trans, root, reloc_root,
path, &next_key, NULL,
level, max_level);
ret = replace_path(trans, root, reloc_root, path,
&next_key, level, max_level);
}
if (ret < 0) {
err = ret;
......@@ -1708,16 +2067,6 @@ static noinline_for_stack int merge_reloc_root(struct reloc_control *rc,
btrfs_node_key_to_cpu(path->nodes[level], &key,
path->slots[level]);
replaced = 1;
} else if (leaf) {
/*
* no block got replaced, try replacing file extents
*/
btrfs_item_key_to_cpu(leaf, &key, 0);
ret = replace_file_extents(trans, rc, root, leaf,
&inode_list);
btrfs_tree_unlock(leaf);
free_extent_buffer(leaf);
BUG_ON(ret < 0);
}
ret = walk_up_reloc_tree(reloc_root, path, &level);
......@@ -1734,15 +2083,10 @@ static noinline_for_stack int merge_reloc_root(struct reloc_control *rc,
root_item->drop_level = level;
nr = trans->blocks_used;
btrfs_end_transaction(trans, root);
btrfs_end_transaction_throttle(trans, root);
btrfs_btree_balance_dirty(root, nr);
/*
* put inodes outside transaction, otherwise we may deadlock.
*/
put_inodes(&inode_list);
if (replaced && rc->stage == UPDATE_DATA_PTRS)
invalidate_extent_cache(root, &key, &next_key);
}
......@@ -1765,87 +2109,125 @@ static noinline_for_stack int merge_reloc_root(struct reloc_control *rc,
sizeof(root_item->drop_progress));
root_item->drop_level = 0;
btrfs_set_root_refs(root_item, 0);
btrfs_update_reloc_root(trans, root);
}
nr = trans->blocks_used;
btrfs_end_transaction(trans, root);
btrfs_end_transaction_throttle(trans, root);
btrfs_btree_balance_dirty(root, nr);
put_inodes(&inode_list);
if (replaced && rc->stage == UPDATE_DATA_PTRS)
invalidate_extent_cache(root, &key, &next_key);
return err;
}
/*
* callback for the work threads.
* this function merges reloc tree with corresponding fs tree,
* and then drops the reloc tree.
*/
static void merge_func(struct btrfs_work *work)
static noinline_for_stack
int prepare_to_merge(struct reloc_control *rc, int err)
{
struct btrfs_trans_handle *trans;
struct btrfs_root *root;
struct btrfs_root *root = rc->extent_root;
struct btrfs_root *reloc_root;
struct async_merge *async;
struct btrfs_trans_handle *trans;
LIST_HEAD(reloc_roots);
u64 num_bytes = 0;
int ret;
int retries = 0;
async = container_of(work, struct async_merge, work);
reloc_root = async->root;
mutex_lock(&root->fs_info->trans_mutex);
rc->merging_rsv_size += root->nodesize * (BTRFS_MAX_LEVEL - 1) * 2;
rc->merging_rsv_size += rc->nodes_relocated * 2;
mutex_unlock(&root->fs_info->trans_mutex);
again:
if (!err) {
num_bytes = rc->merging_rsv_size;
ret = btrfs_block_rsv_add(NULL, root, rc->block_rsv,
num_bytes, &retries);
if (ret)
err = ret;
}
trans = btrfs_join_transaction(rc->extent_root, 1);
if (!err) {
if (num_bytes != rc->merging_rsv_size) {
btrfs_end_transaction(trans, rc->extent_root);
btrfs_block_rsv_release(rc->extent_root,
rc->block_rsv, num_bytes);
retries = 0;
goto again;
}
}
rc->merge_reloc_tree = 1;
while (!list_empty(&rc->reloc_roots)) {
reloc_root = list_entry(rc->reloc_roots.next,
struct btrfs_root, root_list);
list_del_init(&reloc_root->root_list);
if (btrfs_root_refs(&reloc_root->root_item) > 0) {
root = read_fs_root(reloc_root->fs_info,
reloc_root->root_key.offset);
BUG_ON(IS_ERR(root));
BUG_ON(root->reloc_root != reloc_root);
merge_reloc_root(async->rc, root);
trans = btrfs_start_transaction(root, 0);
/*
* set reference count to 1, so btrfs_recover_relocation
* knows it should resumes merging
*/
if (!err)
btrfs_set_root_refs(&reloc_root->root_item, 1);
btrfs_update_reloc_root(trans, root);
btrfs_end_transaction(trans, root);
}
btrfs_drop_snapshot(reloc_root, 0);
list_add(&reloc_root->root_list, &reloc_roots);
}
if (atomic_dec_and_test(async->num_pending))
complete(async->done);
list_splice(&reloc_roots, &rc->reloc_roots);
kfree(async);
if (!err)
btrfs_commit_transaction(trans, rc->extent_root);
else
btrfs_end_transaction(trans, rc->extent_root);
return err;
}
static int merge_reloc_roots(struct reloc_control *rc)
static noinline_for_stack
int merge_reloc_roots(struct reloc_control *rc)
{
struct async_merge *async;
struct btrfs_root *root;
struct completion done;
atomic_t num_pending;
init_completion(&done);
atomic_set(&num_pending, 1);
struct btrfs_root *reloc_root;
LIST_HEAD(reloc_roots);
int found = 0;
int ret;
again:
root = rc->extent_root;
mutex_lock(&root->fs_info->trans_mutex);
list_splice_init(&rc->reloc_roots, &reloc_roots);
mutex_unlock(&root->fs_info->trans_mutex);
while (!list_empty(&rc->reloc_roots)) {
root = list_entry(rc->reloc_roots.next,
while (!list_empty(&reloc_roots)) {
found = 1;
reloc_root = list_entry(reloc_roots.next,
struct btrfs_root, root_list);
list_del_init(&root->root_list);
async = kmalloc(sizeof(*async), GFP_NOFS);
BUG_ON(!async);
async->work.func = merge_func;
async->work.flags = 0;
async->rc = rc;
async->root = root;
async->done = &done;
async->num_pending = &num_pending;
atomic_inc(&num_pending);
btrfs_queue_worker(&rc->workers, &async->work);
}
if (btrfs_root_refs(&reloc_root->root_item) > 0) {
root = read_fs_root(reloc_root->fs_info,
reloc_root->root_key.offset);
BUG_ON(IS_ERR(root));
BUG_ON(root->reloc_root != reloc_root);
if (!atomic_dec_and_test(&num_pending))
wait_for_completion(&done);
ret = merge_reloc_root(rc, root);
BUG_ON(ret);
} else {
list_del_init(&reloc_root->root_list);
}
btrfs_drop_snapshot(reloc_root, rc->block_rsv, 0);
}
if (found) {
found = 0;
goto again;
}
BUG_ON(!RB_EMPTY_ROOT(&rc->reloc_root_tree.rb_root));
return 0;
}
......@@ -1876,119 +2258,169 @@ static int record_reloc_root_in_trans(struct btrfs_trans_handle *trans,
return btrfs_record_root_in_trans(trans, root);
}
/*
* select one tree from trees that references the block.
* for blocks in refernce counted trees, we preper reloc tree.
* if no reloc tree found and reloc_only is true, NULL is returned.
*/
static struct btrfs_root *__select_one_root(struct btrfs_trans_handle *trans,
static noinline_for_stack
struct btrfs_root *select_reloc_root(struct btrfs_trans_handle *trans,
struct reloc_control *rc,
struct backref_node *node,
struct backref_edge *edges[],
int *nr, int reloc_only)
struct backref_edge *edges[], int *nr)
{
struct backref_node *next;
struct btrfs_root *root;
int index;
int loop = 0;
again:
index = 0;
int index = 0;
next = node;
while (1) {
cond_resched();
next = walk_up_backref(next, edges, &index);
root = next->root;
if (!root) {
BUG_ON(!node->old_root);
goto skip;
}
/* no other choice for non-refernce counted tree */
if (!root->ref_cows) {
BUG_ON(reloc_only);
break;
}
BUG_ON(!root);
BUG_ON(!root->ref_cows);
if (root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID) {
record_reloc_root_in_trans(trans, root);
break;
}
if (loop) {
btrfs_record_root_in_trans(trans, root);
break;
}
if (reloc_only || next != node) {
if (!root->reloc_root)
btrfs_record_root_in_trans(trans, root);
root = root->reloc_root;
/*
* if the reloc tree was created in current
* transation, there is no node in backref tree
* corresponds to the root of the reloc tree.
*/
if (btrfs_root_last_snapshot(&root->root_item) ==
trans->transid - 1)
if (next->new_bytenr != root->node->start) {
BUG_ON(next->new_bytenr);
BUG_ON(!list_empty(&next->list));
next->new_bytenr = root->node->start;
next->root = root;
list_add_tail(&next->list,
&rc->backref_cache.changed);
__mark_block_processed(rc, next);
break;
}
skip:
WARN_ON(1);
root = NULL;
next = walk_down_backref(edges, &index);
if (!next || next->level <= node->level)
break;
}
if (!root)
return NULL;
if (!root && !loop && !reloc_only) {
loop = 1;
goto again;
}
if (root)
*nr = index;
else
*nr = 0;
next = node;
/* setup backref node path for btrfs_reloc_cow_block */
while (1) {
rc->backref_cache.path[next->level] = next;
if (--index < 0)
break;
next = edges[index]->node[UPPER];
}
return root;
}
/*
* select a tree root for relocation. return NULL if the block
* is reference counted. we should use do_relocation() in this
* case. return a tree root pointer if the block isn't reference
* counted. return -ENOENT if the block is root of reloc tree.
*/
static noinline_for_stack
struct btrfs_root *select_one_root(struct btrfs_trans_handle *trans,
struct backref_node *node)
{
struct backref_node *next;
struct btrfs_root *root;
struct btrfs_root *fs_root = NULL;
struct backref_edge *edges[BTRFS_MAX_LEVEL - 1];
int nr;
return __select_one_root(trans, node, edges, &nr, 0);
int index = 0;
next = node;
while (1) {
cond_resched();
next = walk_up_backref(next, edges, &index);
root = next->root;
BUG_ON(!root);
/* no other choice for non-refernce counted tree */
if (!root->ref_cows)
return root;
if (root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID)
fs_root = root;
if (next != node)
return NULL;
next = walk_down_backref(edges, &index);
if (!next || next->level <= node->level)
break;
}
if (!fs_root)
return ERR_PTR(-ENOENT);
return fs_root;
}
static noinline_for_stack
struct btrfs_root *select_reloc_root(struct btrfs_trans_handle *trans,
struct backref_node *node,
struct backref_edge *edges[], int *nr)
u64 calcu_metadata_size(struct reloc_control *rc,
struct backref_node *node, int reserve)
{
return __select_one_root(trans, node, edges, nr, 1);
}
struct backref_node *next = node;
struct backref_edge *edge;
struct backref_edge *edges[BTRFS_MAX_LEVEL - 1];
u64 num_bytes = 0;
int index = 0;
static void grab_path_buffers(struct btrfs_path *path,
struct backref_node *node,
struct backref_edge *edges[], int nr)
{
int i = 0;
BUG_ON(reserve && node->processed);
while (next) {
cond_resched();
while (1) {
drop_node_buffer(node);
node->eb = path->nodes[node->level];
BUG_ON(!node->eb);
if (path->locks[node->level])
node->locked = 1;
path->nodes[node->level] = NULL;
path->locks[node->level] = 0;
if (i >= nr)
if (next->processed && (reserve || next != node))
break;
num_bytes += btrfs_level_size(rc->extent_root,
next->level);
if (list_empty(&next->upper))
break;
edges[i]->blockptr = node->eb->start;
node = edges[i]->node[UPPER];
i++;
edge = list_entry(next->upper.next,
struct backref_edge, list[LOWER]);
edges[index++] = edge;
next = edge->node[UPPER];
}
next = walk_down_backref(edges, &index);
}
return num_bytes;
}
static int reserve_metadata_space(struct btrfs_trans_handle *trans,
struct reloc_control *rc,
struct backref_node *node)
{
struct btrfs_root *root = rc->extent_root;
u64 num_bytes;
int ret;
num_bytes = calcu_metadata_size(rc, node, 1) * 2;
trans->block_rsv = rc->block_rsv;
ret = btrfs_block_rsv_add(trans, root, rc->block_rsv, num_bytes,
&rc->block_rsv_retries);
if (ret) {
if (ret == -EAGAIN)
rc->commit_transaction = 1;
return ret;
}
rc->block_rsv_retries = 0;
return 0;
}
static void release_metadata_space(struct reloc_control *rc,
struct backref_node *node)
{
u64 num_bytes = calcu_metadata_size(rc, node, 0) * 2;
btrfs_block_rsv_release(rc->extent_root, rc->block_rsv, num_bytes);
}
/*
......@@ -1999,6 +2431,7 @@ static void grab_path_buffers(struct btrfs_path *path,
* in that case this function just updates pointers.
*/
static int do_relocation(struct btrfs_trans_handle *trans,
struct reloc_control *rc,
struct backref_node *node,
struct btrfs_key *key,
struct btrfs_path *path, int lowest)
......@@ -2019,18 +2452,25 @@ static int do_relocation(struct btrfs_trans_handle *trans,
BUG_ON(lowest && node->eb);
path->lowest_level = node->level + 1;
rc->backref_cache.path[node->level] = node;
list_for_each_entry(edge, &node->upper, list[LOWER]) {
cond_resched();
if (node->eb && node->eb->start == edge->blockptr)
continue;
upper = edge->node[UPPER];
root = select_reloc_root(trans, upper, edges, &nr);
if (!root)
continue;
root = select_reloc_root(trans, rc, upper, edges, &nr);
BUG_ON(!root);
if (upper->eb && !upper->locked)
if (upper->eb && !upper->locked) {
if (!lowest) {
ret = btrfs_bin_search(upper->eb, key,
upper->level, &slot);
BUG_ON(ret);
bytenr = btrfs_node_blockptr(upper->eb, slot);
if (node->eb->start == bytenr)
goto next;
}
drop_node_buffer(upper);
}
if (!upper->eb) {
ret = btrfs_search_slot(trans, root, key, path, 0, 1);
......@@ -2040,11 +2480,17 @@ static int do_relocation(struct btrfs_trans_handle *trans,
}
BUG_ON(ret > 0);
slot = path->slots[upper->level];
if (!upper->eb) {
upper->eb = path->nodes[upper->level];
path->nodes[upper->level] = NULL;
} else {
BUG_ON(upper->eb != path->nodes[upper->level]);
}
btrfs_unlock_up_safe(path, upper->level + 1);
grab_path_buffers(path, upper, edges, nr);
upper->locked = 1;
path->locks[upper->level] = 0;
slot = path->slots[upper->level];
btrfs_release_path(NULL, path);
} else {
ret = btrfs_bin_search(upper->eb, key, upper->level,
......@@ -2053,14 +2499,11 @@ static int do_relocation(struct btrfs_trans_handle *trans,
}
bytenr = btrfs_node_blockptr(upper->eb, slot);
if (!lowest) {
if (node->eb->start == bytenr) {
btrfs_tree_unlock(upper->eb);
upper->locked = 0;
continue;
}
if (lowest) {
BUG_ON(bytenr != node->bytenr);
} else {
BUG_ON(node->bytenr != bytenr);
if (node->eb->start == bytenr)
goto next;
}
blocksize = btrfs_level_size(root, node->level);
......@@ -2072,13 +2515,13 @@ static int do_relocation(struct btrfs_trans_handle *trans,
if (!node->eb) {
ret = btrfs_cow_block(trans, root, eb, upper->eb,
slot, &eb);
btrfs_tree_unlock(eb);
free_extent_buffer(eb);
if (ret < 0) {
err = ret;
break;
goto next;
}
btrfs_set_lock_blocking(eb);
node->eb = eb;
node->locked = 1;
BUG_ON(node->eb != eb);
} else {
btrfs_set_node_blockptr(upper->eb, slot,
node->eb->start);
......@@ -2096,67 +2539,80 @@ static int do_relocation(struct btrfs_trans_handle *trans,
ret = btrfs_drop_subtree(trans, root, eb, upper->eb);
BUG_ON(ret);
}
if (!lowest) {
btrfs_tree_unlock(upper->eb);
upper->locked = 0;
next:
if (!upper->pending)
drop_node_buffer(upper);
else
unlock_node_buffer(upper);
if (err)
break;
}
if (!err && node->pending) {
drop_node_buffer(node);
list_move_tail(&node->list, &rc->backref_cache.changed);
node->pending = 0;
}
path->lowest_level = 0;
BUG_ON(err == -ENOSPC);
return err;
}
static int link_to_upper(struct btrfs_trans_handle *trans,
struct reloc_control *rc,
struct backref_node *node,
struct btrfs_path *path)
{
struct btrfs_key key;
if (!node->eb || list_empty(&node->upper))
return 0;
btrfs_node_key_to_cpu(node->eb, &key, 0);
return do_relocation(trans, node, &key, path, 0);
return do_relocation(trans, rc, node, &key, path, 0);
}
static int finish_pending_nodes(struct btrfs_trans_handle *trans,
struct backref_cache *cache,
struct btrfs_path *path)
struct reloc_control *rc,
struct btrfs_path *path, int err)
{
LIST_HEAD(list);
struct backref_cache *cache = &rc->backref_cache;
struct backref_node *node;
int level;
int ret;
int err = 0;
for (level = 0; level < BTRFS_MAX_LEVEL; level++) {
while (!list_empty(&cache->pending[level])) {
node = list_entry(cache->pending[level].next,
struct backref_node, lower);
BUG_ON(node->level != level);
struct backref_node, list);
list_move_tail(&node->list, &list);
BUG_ON(!node->pending);
ret = link_to_upper(trans, node, path);
if (!err) {
ret = link_to_upper(trans, rc, node, path);
if (ret < 0)
err = ret;
/*
* this remove the node from the pending list and
* may add some other nodes to the level + 1
* pending list
*/
remove_backref_node(cache, node);
}
}
BUG_ON(!RB_EMPTY_ROOT(&cache->rb_root));
list_splice_init(&list, &cache->pending[level]);
}
return err;
}
static void mark_block_processed(struct reloc_control *rc,
u64 bytenr, u32 blocksize)
{
set_extent_bits(&rc->processed_blocks, bytenr, bytenr + blocksize - 1,
EXTENT_DIRTY, GFP_NOFS);
}
static void __mark_block_processed(struct reloc_control *rc,
struct backref_node *node)
{
u32 blocksize;
if (node->level == 0 ||
in_block_group(node->bytenr, rc->block_group)) {
blocksize = btrfs_level_size(rc->extent_root, node->level);
set_extent_bits(&rc->processed_blocks, node->bytenr,
node->bytenr + blocksize - 1, EXTENT_DIRTY,
GFP_NOFS);
mark_block_processed(rc, node->bytenr, blocksize);
}
node->processed = 1;
}
......@@ -2179,7 +2635,7 @@ static void update_processed_blocks(struct reloc_control *rc,
if (next->processed)
break;
mark_block_processed(rc, next);
__mark_block_processed(rc, next);
if (list_empty(&next->upper))
break;
......@@ -2202,138 +2658,6 @@ static int tree_block_processed(u64 bytenr, u32 blocksize,
return 0;
}
/*
* check if there are any file extent pointers in the leaf point to
* data require processing
*/
static int check_file_extents(struct reloc_control *rc,
u64 bytenr, u32 blocksize, u64 ptr_gen)
{
struct btrfs_key found_key;
struct btrfs_file_extent_item *fi;
struct extent_buffer *leaf;
u32 nritems;
int i;
int ret = 0;
leaf = read_tree_block(rc->extent_root, bytenr, blocksize, ptr_gen);
nritems = btrfs_header_nritems(leaf);
for (i = 0; i < nritems; i++) {
cond_resched();
btrfs_item_key_to_cpu(leaf, &found_key, i);
if (found_key.type != BTRFS_EXTENT_DATA_KEY)
continue;
fi = btrfs_item_ptr(leaf, i, struct btrfs_file_extent_item);
if (btrfs_file_extent_type(leaf, fi) ==
BTRFS_FILE_EXTENT_INLINE)
continue;
bytenr = btrfs_file_extent_disk_bytenr(leaf, fi);
if (bytenr == 0)
continue;
if (in_block_group(bytenr, rc->block_group)) {
ret = 1;
break;
}
}
free_extent_buffer(leaf);
return ret;
}
/*
* scan child blocks of a given block to find blocks require processing
*/
static int add_child_blocks(struct btrfs_trans_handle *trans,
struct reloc_control *rc,
struct backref_node *node,
struct rb_root *blocks)
{
struct tree_block *block;
struct rb_node *rb_node;
u64 bytenr;
u64 ptr_gen;
u32 blocksize;
u32 nritems;
int i;
int err = 0;
nritems = btrfs_header_nritems(node->eb);
blocksize = btrfs_level_size(rc->extent_root, node->level - 1);
for (i = 0; i < nritems; i++) {
cond_resched();
bytenr = btrfs_node_blockptr(node->eb, i);
ptr_gen = btrfs_node_ptr_generation(node->eb, i);
if (ptr_gen == trans->transid)
continue;
if (!in_block_group(bytenr, rc->block_group) &&
(node->level > 1 || rc->stage == MOVE_DATA_EXTENTS))
continue;
if (tree_block_processed(bytenr, blocksize, rc))
continue;
readahead_tree_block(rc->extent_root,
bytenr, blocksize, ptr_gen);
}
for (i = 0; i < nritems; i++) {
cond_resched();
bytenr = btrfs_node_blockptr(node->eb, i);
ptr_gen = btrfs_node_ptr_generation(node->eb, i);
if (ptr_gen == trans->transid)
continue;
if (!in_block_group(bytenr, rc->block_group) &&
(node->level > 1 || rc->stage == MOVE_DATA_EXTENTS))
continue;
if (tree_block_processed(bytenr, blocksize, rc))
continue;
if (!in_block_group(bytenr, rc->block_group) &&
!check_file_extents(rc, bytenr, blocksize, ptr_gen))
continue;
block = kmalloc(sizeof(*block), GFP_NOFS);
if (!block) {
err = -ENOMEM;
break;
}
block->bytenr = bytenr;
btrfs_node_key_to_cpu(node->eb, &block->key, i);
block->level = node->level - 1;
block->key_ready = 1;
rb_node = tree_insert(blocks, block->bytenr, &block->rb_node);
BUG_ON(rb_node);
}
if (err)
free_block_list(blocks);
return err;
}
/*
* find adjacent blocks require processing
*/
static noinline_for_stack
int add_adjacent_blocks(struct btrfs_trans_handle *trans,
struct reloc_control *rc,
struct backref_cache *cache,
struct rb_root *blocks, int level,
struct backref_node **upper)
{
struct backref_node *node;
int ret = 0;
WARN_ON(!list_empty(&cache->pending[level]));
if (list_empty(&cache->pending[level + 1]))
return 1;
node = list_entry(cache->pending[level + 1].next,
struct backref_node, lower);
if (node->eb)
ret = add_child_blocks(trans, rc, node, blocks);
*upper = node;
return ret;
}
static int get_tree_block_key(struct reloc_control *rc,
struct tree_block *block)
{
......@@ -2371,40 +2695,53 @@ static int relocate_tree_block(struct btrfs_trans_handle *trans,
struct btrfs_path *path)
{
struct btrfs_root *root;
int ret;
int release = 0;
int ret = 0;
if (!node)
return 0;
BUG_ON(node->processed);
root = select_one_root(trans, node);
if (unlikely(!root)) {
rc->found_old_snapshot = 1;
if (root == ERR_PTR(-ENOENT)) {
update_processed_blocks(rc, node);
return 0;
goto out;
}
if (root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID) {
ret = do_relocation(trans, node, key, path, 1);
if (ret < 0)
goto out;
if (node->level == 0 && rc->stage == UPDATE_DATA_PTRS) {
ret = replace_file_extents(trans, rc, root,
node->eb, NULL);
if (ret < 0)
if (!root || root->ref_cows) {
ret = reserve_metadata_space(trans, rc, node);
if (ret)
goto out;
release = 1;
}
drop_node_buffer(node);
} else if (!root->ref_cows) {
if (root) {
if (root->ref_cows) {
BUG_ON(node->new_bytenr);
BUG_ON(!list_empty(&node->list));
btrfs_record_root_in_trans(trans, root);
root = root->reloc_root;
node->new_bytenr = root->node->start;
node->root = root;
list_add_tail(&node->list, &rc->backref_cache.changed);
} else {
path->lowest_level = node->level;
ret = btrfs_search_slot(trans, root, key, path, 0, 1);
btrfs_release_path(root, path);
if (ret < 0)
goto out;
} else if (root != node->root) {
WARN_ON(node->level > 0 || rc->stage != UPDATE_DATA_PTRS);
if (ret > 0)
ret = 0;
}
if (!ret)
update_processed_blocks(rc, node);
ret = 0;
} else {
ret = do_relocation(trans, rc, node, key, path, 1);
}
out:
drop_node_buffer(node);
if (ret || node->level == 0 || node->cowonly) {
if (release)
release_metadata_space(rc, node);
remove_backref_node(&rc->backref_cache, node);
}
return ret;
}
......@@ -2415,12 +2752,10 @@ static noinline_for_stack
int relocate_tree_blocks(struct btrfs_trans_handle *trans,
struct reloc_control *rc, struct rb_root *blocks)
{
struct backref_cache *cache;
struct backref_node *node;
struct btrfs_path *path;
struct tree_block *block;
struct rb_node *rb_node;
int level = -1;
int ret;
int err = 0;
......@@ -2428,21 +2763,9 @@ int relocate_tree_blocks(struct btrfs_trans_handle *trans,
if (!path)
return -ENOMEM;
cache = kmalloc(sizeof(*cache), GFP_NOFS);
if (!cache) {
btrfs_free_path(path);
return -ENOMEM;
}
backref_cache_init(cache);
rb_node = rb_first(blocks);
while (rb_node) {
block = rb_entry(rb_node, struct tree_block, rb_node);
if (level == -1)
level = block->level;
else
BUG_ON(level != block->level);
if (!block->key_ready)
reada_tree_block(rc, block);
rb_node = rb_next(rb_node);
......@@ -2460,7 +2783,7 @@ int relocate_tree_blocks(struct btrfs_trans_handle *trans,
while (rb_node) {
block = rb_entry(rb_node, struct tree_block, rb_node);
node = build_backref_tree(rc, cache, &block->key,
node = build_backref_tree(rc, &block->key,
block->level, block->bytenr);
if (IS_ERR(node)) {
err = PTR_ERR(node);
......@@ -2470,77 +2793,16 @@ int relocate_tree_blocks(struct btrfs_trans_handle *trans,
ret = relocate_tree_block(trans, rc, node, &block->key,
path);
if (ret < 0) {
if (ret != -EAGAIN || rb_node == rb_first(blocks))
err = ret;
goto out;
}
remove_backref_node(cache, node);
rb_node = rb_next(rb_node);
}
if (level > 0)
goto out;
free_block_list(blocks);
/*
* now backrefs of some upper level tree blocks have been cached,
* try relocating blocks referenced by these upper level blocks.
*/
while (1) {
struct backref_node *upper = NULL;
if (trans->transaction->in_commit ||
trans->transaction->delayed_refs.flushing)
break;
ret = add_adjacent_blocks(trans, rc, cache, blocks, level,
&upper);
if (ret < 0)
err = ret;
if (ret != 0)
break;
rb_node = rb_first(blocks);
while (rb_node) {
block = rb_entry(rb_node, struct tree_block, rb_node);
if (trans->transaction->in_commit ||
trans->transaction->delayed_refs.flushing)
goto out;
BUG_ON(!block->key_ready);
node = build_backref_tree(rc, cache, &block->key,
level, block->bytenr);
if (IS_ERR(node)) {
err = PTR_ERR(node);
goto out;
}
ret = relocate_tree_block(trans, rc, node,
&block->key, path);
if (ret < 0) {
err = ret;
goto out;
}
remove_backref_node(cache, node);
rb_node = rb_next(rb_node);
}
free_block_list(blocks);
if (upper) {
ret = link_to_upper(trans, upper, path);
if (ret < 0) {
err = ret;
break;
}
remove_backref_node(cache, upper);
}
}
out:
free_block_list(blocks);
err = finish_pending_nodes(trans, rc, path, err);
ret = finish_pending_nodes(trans, cache, path);
if (ret < 0)
err = ret;
kfree(cache);
btrfs_free_path(path);
return err;
}
......@@ -2910,9 +3172,6 @@ static int __add_tree_block(struct reloc_control *rc,
static int block_use_full_backref(struct reloc_control *rc,
struct extent_buffer *eb)
{
struct btrfs_path *path;
struct btrfs_extent_item *ei;
struct btrfs_key key;
u64 flags;
int ret;
......@@ -2920,28 +3179,14 @@ static int block_use_full_backref(struct reloc_control *rc,
btrfs_header_backref_rev(eb) < BTRFS_MIXED_BACKREF_REV)
return 1;
path = btrfs_alloc_path();
BUG_ON(!path);
key.objectid = eb->start;
key.type = BTRFS_EXTENT_ITEM_KEY;
key.offset = eb->len;
path->search_commit_root = 1;
path->skip_locking = 1;
ret = btrfs_search_slot(NULL, rc->extent_root,
&key, path, 0, 0);
ret = btrfs_lookup_extent_info(NULL, rc->extent_root,
eb->start, eb->len, NULL, &flags);
BUG_ON(ret);
ei = btrfs_item_ptr(path->nodes[0], path->slots[0],
struct btrfs_extent_item);
flags = btrfs_extent_flags(path->nodes[0], ei);
BUG_ON(!(flags & BTRFS_EXTENT_FLAG_TREE_BLOCK));
if (flags & BTRFS_BLOCK_FLAG_FULL_BACKREF)
ret = 1;
else
ret = 0;
btrfs_free_path(path);
return ret;
}
......@@ -3114,22 +3359,10 @@ int add_data_references(struct reloc_control *rc,
struct btrfs_extent_inline_ref *iref;
unsigned long ptr;
unsigned long end;
u32 blocksize;
u32 blocksize = btrfs_level_size(rc->extent_root, 0);
int ret;
int err = 0;
ret = get_new_location(rc->data_inode, NULL, extent_key->objectid,
extent_key->offset);
BUG_ON(ret < 0);
if (ret > 0) {
/* the relocated data is fragmented */
rc->extents_skipped++;
btrfs_release_path(rc->extent_root, path);
return 0;
}
blocksize = btrfs_level_size(rc->extent_root, 0);
eb = path->nodes[0];
ptr = btrfs_item_ptr_offset(eb, path->slots[0]);
end = ptr + btrfs_item_size_nr(eb, path->slots[0]);
......@@ -3210,7 +3443,8 @@ int add_data_references(struct reloc_control *rc,
*/
static noinline_for_stack
int find_next_extent(struct btrfs_trans_handle *trans,
struct reloc_control *rc, struct btrfs_path *path)
struct reloc_control *rc, struct btrfs_path *path,
struct btrfs_key *extent_key)
{
struct btrfs_key key;
struct extent_buffer *leaf;
......@@ -3265,6 +3499,7 @@ int find_next_extent(struct btrfs_trans_handle *trans,
rc->search_start = end + 1;
} else {
rc->search_start = key.objectid + key.offset;
memcpy(extent_key, &key, sizeof(key));
return 0;
}
}
......@@ -3302,12 +3537,49 @@ static int check_extent_flags(u64 flags)
return 0;
}
static noinline_for_stack
int prepare_to_relocate(struct reloc_control *rc)
{
struct btrfs_trans_handle *trans;
int ret;
rc->block_rsv = btrfs_alloc_block_rsv(rc->extent_root);
if (!rc->block_rsv)
return -ENOMEM;
/*
* reserve some space for creating reloc trees.
* btrfs_init_reloc_root will use them when there
* is no reservation in transaction handle.
*/
ret = btrfs_block_rsv_add(NULL, rc->extent_root, rc->block_rsv,
rc->extent_root->nodesize * 256,
&rc->block_rsv_retries);
if (ret)
return ret;
rc->block_rsv->refill_used = 1;
btrfs_add_durable_block_rsv(rc->extent_root->fs_info, rc->block_rsv);
memset(&rc->cluster, 0, sizeof(rc->cluster));
rc->search_start = rc->block_group->key.objectid;
rc->extents_found = 0;
rc->nodes_relocated = 0;
rc->merging_rsv_size = 0;
rc->block_rsv_retries = 0;
rc->create_reloc_tree = 1;
set_reloc_control(rc);
trans = btrfs_join_transaction(rc->extent_root, 1);
btrfs_commit_transaction(trans, rc->extent_root);
return 0;
}
static noinline_for_stack int relocate_block_group(struct reloc_control *rc)
{
struct rb_root blocks = RB_ROOT;
struct btrfs_key key;
struct file_extent_cluster *cluster;
struct btrfs_trans_handle *trans = NULL;
struct btrfs_path *path;
struct btrfs_extent_item *ei;
......@@ -3317,33 +3589,25 @@ static noinline_for_stack int relocate_block_group(struct reloc_control *rc)
int ret;
int err = 0;
cluster = kzalloc(sizeof(*cluster), GFP_NOFS);
if (!cluster)
return -ENOMEM;
path = btrfs_alloc_path();
if (!path) {
kfree(cluster);
if (!path)
return -ENOMEM;
}
rc->extents_found = 0;
rc->extents_skipped = 0;
rc->search_start = rc->block_group->key.objectid;
clear_extent_bits(&rc->processed_blocks, 0, (u64)-1, EXTENT_DIRTY,
GFP_NOFS);
rc->create_reloc_root = 1;
set_reloc_control(rc);
trans = btrfs_join_transaction(rc->extent_root, 1);
btrfs_commit_transaction(trans, rc->extent_root);
ret = prepare_to_relocate(rc);
if (ret) {
err = ret;
goto out_free;
}
while (1) {
trans = btrfs_start_transaction(rc->extent_root, 0);
ret = find_next_extent(trans, rc, path);
if (update_backref_cache(trans, &rc->backref_cache)) {
btrfs_end_transaction(trans, rc->extent_root);
continue;
}
ret = find_next_extent(trans, rc, path, &key);
if (ret < 0)
err = ret;
if (ret != 0)
......@@ -3353,9 +3617,7 @@ static noinline_for_stack int relocate_block_group(struct reloc_control *rc)
ei = btrfs_item_ptr(path->nodes[0], path->slots[0],
struct btrfs_extent_item);
btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
item_size = btrfs_item_size_nr(path->nodes[0],
path->slots[0]);
item_size = btrfs_item_size_nr(path->nodes[0], path->slots[0]);
if (item_size >= sizeof(*ei)) {
flags = btrfs_extent_flags(path->nodes[0], ei);
ret = check_extent_flags(flags);
......@@ -3403,66 +3665,93 @@ static noinline_for_stack int relocate_block_group(struct reloc_control *rc)
ret = 0;
}
if (ret < 0) {
err = 0;
err = ret;
break;
}
if (!RB_EMPTY_ROOT(&blocks)) {
ret = relocate_tree_blocks(trans, rc, &blocks);
if (ret < 0) {
if (ret != -EAGAIN) {
err = ret;
break;
}
rc->extents_found--;
rc->search_start = key.objectid;
}
}
ret = btrfs_block_rsv_check(trans, rc->extent_root,
rc->block_rsv, 0, 5);
if (ret < 0) {
if (ret != -EAGAIN) {
err = ret;
WARN_ON(1);
break;
}
rc->commit_transaction = 1;
}
if (rc->commit_transaction) {
rc->commit_transaction = 0;
ret = btrfs_commit_transaction(trans, rc->extent_root);
BUG_ON(ret);
} else {
nr = trans->blocks_used;
btrfs_end_transaction(trans, rc->extent_root);
trans = NULL;
btrfs_end_transaction_throttle(trans, rc->extent_root);
btrfs_btree_balance_dirty(rc->extent_root, nr);
}
trans = NULL;
if (rc->stage == MOVE_DATA_EXTENTS &&
(flags & BTRFS_EXTENT_FLAG_DATA)) {
rc->found_file_extent = 1;
ret = relocate_data_extent(rc->data_inode,
&key, cluster);
&key, &rc->cluster);
if (ret < 0) {
err = ret;
break;
}
}
}
btrfs_free_path(path);
btrfs_release_path(rc->extent_root, path);
clear_extent_bits(&rc->processed_blocks, 0, (u64)-1, EXTENT_DIRTY,
GFP_NOFS);
if (trans) {
nr = trans->blocks_used;
btrfs_end_transaction(trans, rc->extent_root);
btrfs_end_transaction_throttle(trans, rc->extent_root);
btrfs_btree_balance_dirty(rc->extent_root, nr);
}
if (!err) {
ret = relocate_file_extent_cluster(rc->data_inode, cluster);
ret = relocate_file_extent_cluster(rc->data_inode,
&rc->cluster);
if (ret < 0)
err = ret;
}
kfree(cluster);
rc->create_reloc_tree = 0;
set_reloc_control(rc);
rc->create_reloc_root = 0;
smp_mb();
backref_cache_cleanup(&rc->backref_cache);
btrfs_block_rsv_release(rc->extent_root, rc->block_rsv, (u64)-1);
if (rc->extents_found > 0) {
trans = btrfs_join_transaction(rc->extent_root, 1);
btrfs_commit_transaction(trans, rc->extent_root);
}
err = prepare_to_merge(rc, err);
merge_reloc_roots(rc);
rc->merge_reloc_tree = 0;
unset_reloc_control(rc);
btrfs_block_rsv_release(rc->extent_root, rc->block_rsv, (u64)-1);
/* get rid of pinned extents */
trans = btrfs_join_transaction(rc->extent_root, 1);
btrfs_commit_transaction(trans, rc->extent_root);
out_free:
btrfs_free_block_rsv(rc->extent_root, rc->block_rsv);
btrfs_free_path(path);
return err;
}
......@@ -3488,7 +3777,8 @@ static int __insert_orphan_inode(struct btrfs_trans_handle *trans,
btrfs_set_inode_generation(leaf, item, 1);
btrfs_set_inode_size(leaf, item, 0);
btrfs_set_inode_mode(leaf, item, S_IFREG | 0600);
btrfs_set_inode_flags(leaf, item, BTRFS_INODE_NOCOMPRESS);
btrfs_set_inode_flags(leaf, item, BTRFS_INODE_NOCOMPRESS |
BTRFS_INODE_PREALLOC);
btrfs_mark_buffer_dirty(leaf);
btrfs_release_path(root, path);
out:
......@@ -3500,7 +3790,8 @@ static int __insert_orphan_inode(struct btrfs_trans_handle *trans,
* helper to create inode for data relocation.
* the inode is in data relocation tree and its link count is 0
*/
static struct inode *create_reloc_inode(struct btrfs_fs_info *fs_info,
static noinline_for_stack
struct inode *create_reloc_inode(struct btrfs_fs_info *fs_info,
struct btrfs_block_group_cache *group)
{
struct inode *inode = NULL;
......@@ -3516,7 +3807,8 @@ static struct inode *create_reloc_inode(struct btrfs_fs_info *fs_info,
return ERR_CAST(root);
trans = btrfs_start_transaction(root, 6);
BUG_ON(!trans);
if (IS_ERR(trans))
return ERR_CAST(trans);
err = btrfs_find_free_objectid(trans, root, objectid, &objectid);
if (err)
......@@ -3536,7 +3828,6 @@ static struct inode *create_reloc_inode(struct btrfs_fs_info *fs_info,
out:
nr = trans->blocks_used;
btrfs_end_transaction(trans, root);
btrfs_btree_balance_dirty(root, nr);
if (err) {
if (inode)
......@@ -3546,6 +3837,21 @@ static struct inode *create_reloc_inode(struct btrfs_fs_info *fs_info,
return inode;
}
static struct reloc_control *alloc_reloc_control(void)
{
struct reloc_control *rc;
rc = kzalloc(sizeof(*rc), GFP_NOFS);
if (!rc)
return NULL;
INIT_LIST_HEAD(&rc->reloc_roots);
backref_cache_init(&rc->backref_cache);
mapping_tree_init(&rc->reloc_root_tree);
extent_io_tree_init(&rc->processed_blocks, NULL, GFP_NOFS);
return rc;
}
/*
* function to relocate all extents in a block group.
*/
......@@ -3557,15 +3863,12 @@ int btrfs_relocate_block_group(struct btrfs_root *extent_root, u64 group_start)
int rw = 0;
int err = 0;
rc = kzalloc(sizeof(*rc), GFP_NOFS);
rc = alloc_reloc_control();
if (!rc)
return -ENOMEM;
mapping_tree_init(&rc->reloc_root_tree);
extent_io_tree_init(&rc->processed_blocks, NULL, GFP_NOFS);
INIT_LIST_HEAD(&rc->reloc_roots);
rc->extent_root = extent_root;
rc->block_group = btrfs_lookup_block_group(fs_info, group_start);
BUG_ON(!rc->block_group);
......@@ -3578,9 +3881,6 @@ int btrfs_relocate_block_group(struct btrfs_root *extent_root, u64 group_start)
rw = 1;
}
btrfs_init_workers(&rc->workers, "relocate",
fs_info->thread_pool_size, NULL);
rc->data_inode = create_reloc_inode(fs_info, rc->block_group);
if (IS_ERR(rc->data_inode)) {
err = PTR_ERR(rc->data_inode);
......@@ -3596,9 +3896,6 @@ int btrfs_relocate_block_group(struct btrfs_root *extent_root, u64 group_start)
btrfs_wait_ordered_extents(fs_info->tree_root, 0, 0);
while (1) {
rc->extents_found = 0;
rc->extents_skipped = 0;
mutex_lock(&fs_info->cleaner_mutex);
btrfs_clean_old_snapshots(fs_info->tree_root);
......@@ -3607,7 +3904,7 @@ int btrfs_relocate_block_group(struct btrfs_root *extent_root, u64 group_start)
mutex_unlock(&fs_info->cleaner_mutex);
if (ret < 0) {
err = ret;
break;
goto out;
}
if (rc->extents_found == 0)
......@@ -3621,18 +3918,6 @@ int btrfs_relocate_block_group(struct btrfs_root *extent_root, u64 group_start)
invalidate_mapping_pages(rc->data_inode->i_mapping,
0, -1);
rc->stage = UPDATE_DATA_PTRS;
} else if (rc->stage == UPDATE_DATA_PTRS &&
rc->extents_skipped >= rc->extents_found) {
iput(rc->data_inode);
rc->data_inode = create_reloc_inode(fs_info,
rc->block_group);
if (IS_ERR(rc->data_inode)) {
err = PTR_ERR(rc->data_inode);
rc->data_inode = NULL;
break;
}
rc->stage = MOVE_DATA_EXTENTS;
rc->found_file_extent = 0;
}
}
......@@ -3648,7 +3933,6 @@ int btrfs_relocate_block_group(struct btrfs_root *extent_root, u64 group_start)
if (err && rw)
btrfs_set_block_group_rw(extent_root, rc->block_group);
iput(rc->data_inode);
btrfs_stop_workers(&rc->workers);
btrfs_put_block_group(rc->block_group);
kfree(rc);
return err;
......@@ -3752,20 +4036,20 @@ int btrfs_recover_relocation(struct btrfs_root *root)
if (list_empty(&reloc_roots))
goto out;
rc = kzalloc(sizeof(*rc), GFP_NOFS);
rc = alloc_reloc_control();
if (!rc) {
err = -ENOMEM;
goto out;
}
mapping_tree_init(&rc->reloc_root_tree);
INIT_LIST_HEAD(&rc->reloc_roots);
btrfs_init_workers(&rc->workers, "relocate",
root->fs_info->thread_pool_size, NULL);
rc->extent_root = root->fs_info->extent_root;
set_reloc_control(rc);
trans = btrfs_join_transaction(rc->extent_root, 1);
rc->merge_reloc_tree = 1;
while (!list_empty(&reloc_roots)) {
reloc_root = list_entry(reloc_roots.next,
struct btrfs_root, root_list);
......@@ -3785,20 +4069,16 @@ int btrfs_recover_relocation(struct btrfs_root *root)
fs_root->reloc_root = reloc_root;
}
trans = btrfs_start_transaction(rc->extent_root, 1);
btrfs_commit_transaction(trans, rc->extent_root);
merge_reloc_roots(rc);
unset_reloc_control(rc);
trans = btrfs_start_transaction(rc->extent_root, 1);
trans = btrfs_join_transaction(rc->extent_root, 1);
btrfs_commit_transaction(trans, rc->extent_root);
out:
if (rc) {
btrfs_stop_workers(&rc->workers);
kfree(rc);
}
while (!list_empty(&reloc_roots)) {
reloc_root = list_entry(reloc_roots.next,
struct btrfs_root, root_list);
......@@ -3864,3 +4144,130 @@ int btrfs_reloc_clone_csums(struct inode *inode, u64 file_pos, u64 len)
btrfs_put_ordered_extent(ordered);
return 0;
}
void btrfs_reloc_cow_block(struct btrfs_trans_handle *trans,
struct btrfs_root *root, struct extent_buffer *buf,
struct extent_buffer *cow)
{
struct reloc_control *rc;
struct backref_node *node;
int first_cow = 0;
int level;
int ret;
rc = root->fs_info->reloc_ctl;
if (!rc)
return;
BUG_ON(rc->stage == UPDATE_DATA_PTRS &&
root->root_key.objectid == BTRFS_DATA_RELOC_TREE_OBJECTID);
level = btrfs_header_level(buf);
if (btrfs_header_generation(buf) <=
btrfs_root_last_snapshot(&root->root_item))
first_cow = 1;
if (root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID &&
rc->create_reloc_tree) {
WARN_ON(!first_cow && level == 0);
node = rc->backref_cache.path[level];
BUG_ON(node->bytenr != buf->start &&
node->new_bytenr != buf->start);
drop_node_buffer(node);
extent_buffer_get(cow);
node->eb = cow;
node->new_bytenr = cow->start;
if (!node->pending) {
list_move_tail(&node->list,
&rc->backref_cache.pending[level]);
node->pending = 1;
}
if (first_cow)
__mark_block_processed(rc, node);
if (first_cow && level > 0)
rc->nodes_relocated += buf->len;
}
if (level == 0 && first_cow && rc->stage == UPDATE_DATA_PTRS) {
ret = replace_file_extents(trans, rc, root, cow);
BUG_ON(ret);
}
}
/*
* called before creating snapshot. it calculates metadata reservation
* requried for relocating tree blocks in the snapshot
*/
void btrfs_reloc_pre_snapshot(struct btrfs_trans_handle *trans,
struct btrfs_pending_snapshot *pending,
u64 *bytes_to_reserve)
{
struct btrfs_root *root;
struct reloc_control *rc;
root = pending->root;
if (!root->reloc_root)
return;
rc = root->fs_info->reloc_ctl;
if (!rc->merge_reloc_tree)
return;
root = root->reloc_root;
BUG_ON(btrfs_root_refs(&root->root_item) == 0);
/*
* relocation is in the stage of merging trees. the space
* used by merging a reloc tree is twice the size of
* relocated tree nodes in the worst case. half for cowing
* the reloc tree, half for cowing the fs tree. the space
* used by cowing the reloc tree will be freed after the
* tree is dropped. if we create snapshot, cowing the fs
* tree may use more space than it frees. so we need
* reserve extra space.
*/
*bytes_to_reserve += rc->nodes_relocated;
}
/*
* called after snapshot is created. migrate block reservation
* and create reloc root for the newly created snapshot
*/
void btrfs_reloc_post_snapshot(struct btrfs_trans_handle *trans,
struct btrfs_pending_snapshot *pending)
{
struct btrfs_root *root = pending->root;
struct btrfs_root *reloc_root;
struct btrfs_root *new_root;
struct reloc_control *rc;
int ret;
if (!root->reloc_root)
return;
rc = root->fs_info->reloc_ctl;
rc->merging_rsv_size += rc->nodes_relocated;
if (rc->merge_reloc_tree) {
ret = btrfs_block_rsv_migrate(&pending->block_rsv,
rc->block_rsv,
rc->nodes_relocated);
BUG_ON(ret);
}
new_root = pending->snap;
reloc_root = create_reloc_root(trans, root->reloc_root,
new_root->root_key.objectid);
__add_reloc_root(reloc_root);
new_root->reloc_root = reloc_root;
if (rc->create_reloc_tree) {
ret = clone_backref_node(trans, rc, root, reloc_root);
BUG_ON(ret);
}
}
fs/btrfs/transaction.c
View file @ 3fd0a558
......@@ -853,6 +853,7 @@ static noinline int create_pending_snapshot(struct btrfs_trans_handle *trans,
goto fail;
}
btrfs_reloc_pre_snapshot(trans, pending, &to_reserve);
btrfs_orphan_pre_snapshot(trans, pending, &to_reserve);
if (to_reserve > 0) {
......@@ -924,6 +925,7 @@ static noinline int create_pending_snapshot(struct btrfs_trans_handle *trans,
pending->snap = btrfs_read_fs_root_no_name(root->fs_info, &key);
BUG_ON(IS_ERR(pending->snap));
btrfs_reloc_post_snapshot(trans, pending);
btrfs_orphan_post_snapshot(trans, pending);
fail:
kfree(new_root_item);
......@@ -1213,9 +1215,9 @@ int btrfs_clean_old_snapshots(struct btrfs_root *root)
if (btrfs_header_backref_rev(root->node) <
BTRFS_MIXED_BACKREF_REV)
btrfs_drop_snapshot(root, 0);
btrfs_drop_snapshot(root, NULL, 0);
else
btrfs_drop_snapshot(root, 1);
btrfs_drop_snapshot(root, NULL, 1);
}
return 0;
}
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