*/
struct btrfs_key location;
+ /* Lock for counters */
+ spinlock_t lock;
+
/* the extent_tree has caches of all the extent mappings to disk */
struct extent_map_tree extent_tree;
* items we think we'll end up using, and reserved_extents is the number
* of extent items we've reserved metadata for.
*/
- atomic_t outstanding_extents;
- atomic_t reserved_extents;
+ unsigned outstanding_extents;
+ unsigned reserved_extents;
/*
* ordered_data_close is set by truncate when a file that used
BTRFS_I(inode)->disk_i_size = size;
}
+static inline bool btrfs_is_free_space_inode(struct btrfs_root *root,
+ struct inode *inode)
+{
+ if (root == root->fs_info->tree_root ||
+ BTRFS_I(inode)->location.objectid == BTRFS_FREE_INO_OBJECTID)
+ return true;
+ return false;
+}
+
#endif
{
int i;
for (i = 0; i < BTRFS_MAX_LEVEL; i++) {
- if (p->nodes[i] && p->locks[i])
- btrfs_set_lock_blocking(p->nodes[i]);
+ if (!p->nodes[i] || !p->locks[i])
+ continue;
+ btrfs_set_lock_blocking_rw(p->nodes[i], p->locks[i]);
+ if (p->locks[i] == BTRFS_READ_LOCK)
+ p->locks[i] = BTRFS_READ_LOCK_BLOCKING;
+ else if (p->locks[i] == BTRFS_WRITE_LOCK)
+ p->locks[i] = BTRFS_WRITE_LOCK_BLOCKING;
}
}
* for held
*/
noinline void btrfs_clear_path_blocking(struct btrfs_path *p,
- struct extent_buffer *held)
+ struct extent_buffer *held, int held_rw)
{
int i;
* really sure by forcing the path to blocking before we clear
* the path blocking.
*/
- if (held)
- btrfs_set_lock_blocking(held);
+ if (held) {
+ btrfs_set_lock_blocking_rw(held, held_rw);
+ if (held_rw == BTRFS_WRITE_LOCK)
+ held_rw = BTRFS_WRITE_LOCK_BLOCKING;
+ else if (held_rw == BTRFS_READ_LOCK)
+ held_rw = BTRFS_READ_LOCK_BLOCKING;
+ }
btrfs_set_path_blocking(p);
#endif
for (i = BTRFS_MAX_LEVEL - 1; i >= 0; i--) {
- if (p->nodes[i] && p->locks[i])
- btrfs_clear_lock_blocking(p->nodes[i]);
+ if (p->nodes[i] && p->locks[i]) {
+ btrfs_clear_lock_blocking_rw(p->nodes[i], p->locks[i]);
+ if (p->locks[i] == BTRFS_WRITE_LOCK_BLOCKING)
+ p->locks[i] = BTRFS_WRITE_LOCK;
+ else if (p->locks[i] == BTRFS_READ_LOCK_BLOCKING)
+ p->locks[i] = BTRFS_READ_LOCK;
+ }
}
#ifdef CONFIG_DEBUG_LOCK_ALLOC
if (held)
- btrfs_clear_lock_blocking(held);
+ btrfs_clear_lock_blocking_rw(held, held_rw);
#endif
}
if (!p->nodes[i])
continue;
if (p->locks[i]) {
- btrfs_tree_unlock(p->nodes[i]);
+ btrfs_tree_unlock_rw(p->nodes[i], p->locks[i]);
p->locks[i] = 0;
}
free_extent_buffer(p->nodes[i]);
return eb;
}
+/* loop around taking references on and locking the root node of the
+ * tree until you end up with a lock on the root. A locked buffer
+ * is returned, with a reference held.
+ */
+struct extent_buffer *btrfs_read_lock_root_node(struct btrfs_root *root)
+{
+ struct extent_buffer *eb;
+
+ while (1) {
+ eb = btrfs_root_node(root);
+ btrfs_tree_read_lock(eb);
+ if (eb == root->node)
+ break;
+ btrfs_tree_read_unlock(eb);
+ free_extent_buffer(eb);
+ }
+ return eb;
+}
+
/* cowonly root (everything not a reference counted cow subvolume), just get
* put onto a simple dirty list. transaction.c walks this to make sure they
* get properly updated on disk.
for (i = start_slot; i < end_slot; i++) {
int close = 1;
- if (!parent->map_token) {
- map_extent_buffer(parent,
- btrfs_node_key_ptr_offset(i),
- sizeof(struct btrfs_key_ptr),
- &parent->map_token, &parent->kaddr,
- &parent->map_start, &parent->map_len,
- KM_USER1);
- }
btrfs_node_key(parent, &disk_key, i);
if (!progress_passed && comp_keys(&disk_key, progress) < 0)
continue;
last_block = blocknr;
continue;
}
- if (parent->map_token) {
- unmap_extent_buffer(parent, parent->map_token,
- KM_USER1);
- parent->map_token = NULL;
- }
cur = btrfs_find_tree_block(root, blocknr, blocksize);
if (cur)
btrfs_tree_unlock(cur);
free_extent_buffer(cur);
}
- if (parent->map_token) {
- unmap_extent_buffer(parent, parent->map_token,
- KM_USER1);
- parent->map_token = NULL;
- }
return err;
}
struct btrfs_disk_key *tmp = NULL;
struct btrfs_disk_key unaligned;
unsigned long offset;
- char *map_token = NULL;
char *kaddr = NULL;
unsigned long map_start = 0;
unsigned long map_len = 0;
mid = (low + high) / 2;
offset = p + mid * item_size;
- if (!map_token || offset < map_start ||
+ if (!kaddr || offset < map_start ||
(offset + sizeof(struct btrfs_disk_key)) >
map_start + map_len) {
- if (map_token) {
- unmap_extent_buffer(eb, map_token, KM_USER0);
- map_token = NULL;
- }
err = map_private_extent_buffer(eb, offset,
sizeof(struct btrfs_disk_key),
- &map_token, &kaddr,
- &map_start, &map_len, KM_USER0);
+ &kaddr, &map_start, &map_len);
if (!err) {
tmp = (struct btrfs_disk_key *)(kaddr + offset -
high = mid;
else {
*slot = mid;
- if (map_token)
- unmap_extent_buffer(eb, map_token, KM_USER0);
return 0;
}
}
*slot = low;
- if (map_token)
- unmap_extent_buffer(eb, map_token, KM_USER0);
return 1;
}
mid = path->nodes[level];
- WARN_ON(!path->locks[level]);
+ WARN_ON(path->locks[level] != BTRFS_WRITE_LOCK &&
+ path->locks[level] != BTRFS_WRITE_LOCK_BLOCKING);
WARN_ON(btrfs_header_generation(mid) != trans->transid);
orig_ptr = btrfs_node_blockptr(mid, orig_slot);
u32 nr;
u32 blocksize;
u32 nscan = 0;
- bool map = true;
if (level != 1)
return;
nritems = btrfs_header_nritems(node);
nr = slot;
- if (node->map_token || path->skip_locking)
- map = false;
while (1) {
- if (map && !node->map_token) {
- unsigned long offset = btrfs_node_key_ptr_offset(nr);
- map_private_extent_buffer(node, offset,
- sizeof(struct btrfs_key_ptr),
- &node->map_token,
- &node->kaddr,
- &node->map_start,
- &node->map_len, KM_USER1);
- }
if (direction < 0) {
if (nr == 0)
break;
if ((search <= target && target - search <= 65536) ||
(search > target && search - target <= 65536)) {
gen = btrfs_node_ptr_generation(node, nr);
- if (map && node->map_token) {
- unmap_extent_buffer(node, node->map_token,
- KM_USER1);
- node->map_token = NULL;
- }
readahead_tree_block(root, search, blocksize, gen);
nread += blocksize;
}
if ((nread > 65536 || nscan > 32))
break;
}
- if (map && node->map_token) {
- unmap_extent_buffer(node, node->map_token, KM_USER1);
- node->map_token = NULL;
- }
}
/*
t = path->nodes[i];
if (i >= lowest_unlock && i > skip_level && path->locks[i]) {
- btrfs_tree_unlock(t);
+ btrfs_tree_unlock_rw(t, path->locks[i]);
path->locks[i] = 0;
}
}
continue;
if (!path->locks[i])
continue;
- btrfs_tree_unlock(path->nodes[i]);
+ btrfs_tree_unlock_rw(path->nodes[i], path->locks[i]);
path->locks[i] = 0;
}
}
* we can trust our generation number
*/
free_extent_buffer(tmp);
+ btrfs_set_path_blocking(p);
+
tmp = read_tree_block(root, blocknr, blocksize, gen);
if (tmp && btrfs_buffer_uptodate(tmp, gen)) {
*eb_ret = tmp;
static int
setup_nodes_for_search(struct btrfs_trans_handle *trans,
struct btrfs_root *root, struct btrfs_path *p,
- struct extent_buffer *b, int level, int ins_len)
+ struct extent_buffer *b, int level, int ins_len,
+ int *write_lock_level)
{
int ret;
if ((p->search_for_split || ins_len > 0) && btrfs_header_nritems(b) >=
BTRFS_NODEPTRS_PER_BLOCK(root) - 3) {
int sret;
+ if (*write_lock_level < level + 1) {
+ *write_lock_level = level + 1;
+ btrfs_release_path(p);
+ goto again;
+ }
+
sret = reada_for_balance(root, p, level);
if (sret)
goto again;
btrfs_set_path_blocking(p);
sret = split_node(trans, root, p, level);
- btrfs_clear_path_blocking(p, NULL);
+ btrfs_clear_path_blocking(p, NULL, 0);
BUG_ON(sret > 0);
if (sret) {
BTRFS_NODEPTRS_PER_BLOCK(root) / 2) {
int sret;
+ if (*write_lock_level < level + 1) {
+ *write_lock_level = level + 1;
+ btrfs_release_path(p);
+ goto again;
+ }
+
sret = reada_for_balance(root, p, level);
if (sret)
goto again;
btrfs_set_path_blocking(p);
sret = balance_level(trans, root, p, level);
- btrfs_clear_path_blocking(p, NULL);
+ btrfs_clear_path_blocking(p, NULL, 0);
if (sret) {
ret = sret;
int err;
int level;
int lowest_unlock = 1;
+ int root_lock;
+ /* everything at write_lock_level or lower must be write locked */
+ int write_lock_level = 0;
u8 lowest_level = 0;
lowest_level = p->lowest_level;
WARN_ON(lowest_level && ins_len > 0);
WARN_ON(p->nodes[0] != NULL);
- if (ins_len < 0)
+ if (ins_len < 0) {
lowest_unlock = 2;
+ /* when we are removing items, we might have to go up to level
+ * two as we update tree pointers Make sure we keep write
+ * for those levels as well
+ */
+ write_lock_level = 2;
+ } else if (ins_len > 0) {
+ /*
+ * for inserting items, make sure we have a write lock on
+ * level 1 so we can update keys
+ */
+ write_lock_level = 1;
+ }
+
+ if (!cow)
+ write_lock_level = -1;
+
+ if (cow && (p->keep_locks || p->lowest_level))
+ write_lock_level = BTRFS_MAX_LEVEL;
+
again:
+ /*
+ * we try very hard to do read locks on the root
+ */
+ root_lock = BTRFS_READ_LOCK;
+ level = 0;
if (p->search_commit_root) {
+ /*
+ * the commit roots are read only
+ * so we always do read locks
+ */
b = root->commit_root;
extent_buffer_get(b);
+ level = btrfs_header_level(b);
if (!p->skip_locking)
- btrfs_tree_lock(b);
+ btrfs_tree_read_lock(b);
} else {
- if (p->skip_locking)
+ if (p->skip_locking) {
b = btrfs_root_node(root);
- else
- b = btrfs_lock_root_node(root);
+ level = btrfs_header_level(b);
+ } else {
+ /* we don't know the level of the root node
+ * until we actually have it read locked
+ */
+ b = btrfs_read_lock_root_node(root);
+ level = btrfs_header_level(b);
+ if (level <= write_lock_level) {
+ /* whoops, must trade for write lock */
+ btrfs_tree_read_unlock(b);
+ free_extent_buffer(b);
+ b = btrfs_lock_root_node(root);
+ root_lock = BTRFS_WRITE_LOCK;
+
+ /* the level might have changed, check again */
+ level = btrfs_header_level(b);
+ }
+ }
}
+ p->nodes[level] = b;
+ if (!p->skip_locking)
+ p->locks[level] = root_lock;
while (b) {
level = btrfs_header_level(b);
* setup the path here so we can release it under lock
* contention with the cow code
*/
- p->nodes[level] = b;
- if (!p->skip_locking)
- p->locks[level] = 1;
-
if (cow) {
/*
* if we don't really need to cow this block
btrfs_set_path_blocking(p);
+ /*
+ * must have write locks on this node and the
+ * parent
+ */
+ if (level + 1 > write_lock_level) {
+ write_lock_level = level + 1;
+ btrfs_release_path(p);
+ goto again;
+ }
+
err = btrfs_cow_block(trans, root, b,
p->nodes[level + 1],
p->slots[level + 1], &b);
BUG_ON(!cow && ins_len);
p->nodes[level] = b;
- if (!p->skip_locking)
- p->locks[level] = 1;
-
- btrfs_clear_path_blocking(p, NULL);
+ btrfs_clear_path_blocking(p, NULL, 0);
/*
* we have a lock on b and as long as we aren't changing
}
p->slots[level] = slot;
err = setup_nodes_for_search(trans, root, p, b, level,
- ins_len);
+ ins_len, &write_lock_level);
if (err == -EAGAIN)
goto again;
if (err) {
b = p->nodes[level];
slot = p->slots[level];
+ /*
+ * slot 0 is special, if we change the key
+ * we have to update the parent pointer
+ * which means we must have a write lock
+ * on the parent
+ */
+ if (slot == 0 && cow &&
+ write_lock_level < level + 1) {
+ write_lock_level = level + 1;
+ btrfs_release_path(p);
+ goto again;
+ }
+
unlock_up(p, level, lowest_unlock);
if (level == lowest_level) {
}
if (!p->skip_locking) {
- btrfs_clear_path_blocking(p, NULL);
- err = btrfs_try_spin_lock(b);
-
- if (!err) {
- btrfs_set_path_blocking(p);
- btrfs_tree_lock(b);
- btrfs_clear_path_blocking(p, b);
+ level = btrfs_header_level(b);
+ if (level <= write_lock_level) {
+ err = btrfs_try_tree_write_lock(b);
+ if (!err) {
+ btrfs_set_path_blocking(p);
+ btrfs_tree_lock(b);
+ btrfs_clear_path_blocking(p, b,
+ BTRFS_WRITE_LOCK);
+ }
+ p->locks[level] = BTRFS_WRITE_LOCK;
+ } else {
+ 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;
}
} else {
p->slots[level] = slot;
if (ins_len > 0 &&
btrfs_leaf_free_space(root, b) < ins_len) {
+ if (write_lock_level < 1) {
+ write_lock_level = 1;
+ btrfs_release_path(p);
+ goto again;
+ }
+
btrfs_set_path_blocking(p);
err = split_leaf(trans, root, key,
p, ins_len, ret == 0);
- btrfs_clear_path_blocking(p, NULL);
+ btrfs_clear_path_blocking(p, NULL, 0);
BUG_ON(err > 0);
if (err) {
add_root_to_dirty_list(root);
extent_buffer_get(c);
path->nodes[level] = c;
- path->locks[level] = 1;
+ path->locks[level] = BTRFS_WRITE_LOCK;
path->slots[level] = 0;
return 0;
}
if (path->slots[0] == i)
push_space += data_size;
- if (!left->map_token) {
- map_extent_buffer(left, (unsigned long)item,
- sizeof(struct btrfs_item),
- &left->map_token, &left->kaddr,
- &left->map_start, &left->map_len,
- KM_USER1);
- }
-
this_item_size = btrfs_item_size(left, item);
if (this_item_size + sizeof(*item) + push_space > free_space)
break;
break;
i--;
}
- if (left->map_token) {
- unmap_extent_buffer(left, left->map_token, KM_USER1);
- left->map_token = NULL;
- }
if (push_items == 0)
goto out_unlock;
push_space = BTRFS_LEAF_DATA_SIZE(root);
for (i = 0; i < right_nritems; i++) {
item = btrfs_item_nr(right, i);
- if (!right->map_token) {
- map_extent_buffer(right, (unsigned long)item,
- sizeof(struct btrfs_item),
- &right->map_token, &right->kaddr,
- &right->map_start, &right->map_len,
- KM_USER1);
- }
push_space -= btrfs_item_size(right, item);
btrfs_set_item_offset(right, item, push_space);
}
- if (right->map_token) {
- unmap_extent_buffer(right, right->map_token, KM_USER1);
- right->map_token = NULL;
- }
left_nritems -= push_items;
btrfs_set_header_nritems(left, left_nritems);
for (i = 0; i < nr; i++) {
item = btrfs_item_nr(right, i);
- if (!right->map_token) {
- map_extent_buffer(right, (unsigned long)item,
- sizeof(struct btrfs_item),
- &right->map_token, &right->kaddr,
- &right->map_start, &right->map_len,
- KM_USER1);
- }
if (!empty && push_items > 0) {
if (path->slots[0] < i)
push_space += this_item_size + sizeof(*item);
}
- if (right->map_token) {
- unmap_extent_buffer(right, right->map_token, KM_USER1);
- right->map_token = NULL;
- }
-
if (push_items == 0) {
ret = 1;
goto out;
u32 ioff;
item = btrfs_item_nr(left, i);
- if (!left->map_token) {
- map_extent_buffer(left, (unsigned long)item,
- sizeof(struct btrfs_item),
- &left->map_token, &left->kaddr,
- &left->map_start, &left->map_len,
- KM_USER1);
- }
ioff = btrfs_item_offset(left, item);
btrfs_set_item_offset(left, item,
ioff - (BTRFS_LEAF_DATA_SIZE(root) - old_left_item_size));
}
btrfs_set_header_nritems(left, old_left_nritems + push_items);
- if (left->map_token) {
- unmap_extent_buffer(left, left->map_token, KM_USER1);
- left->map_token = NULL;
- }
/* fixup right node */
if (push_items > right_nritems) {
for (i = 0; i < right_nritems; i++) {
item = btrfs_item_nr(right, i);
- if (!right->map_token) {
- map_extent_buffer(right, (unsigned long)item,
- sizeof(struct btrfs_item),
- &right->map_token, &right->kaddr,
- &right->map_start, &right->map_len,
- KM_USER1);
- }
-
push_space = push_space - btrfs_item_size(right, item);
btrfs_set_item_offset(right, item, push_space);
}
- if (right->map_token) {
- unmap_extent_buffer(right, right->map_token, KM_USER1);
- right->map_token = NULL;
- }
btrfs_mark_buffer_dirty(left);
if (right_nritems)
struct btrfs_item *item = btrfs_item_nr(right, i);
u32 ioff;
- if (!right->map_token) {
- map_extent_buffer(right, (unsigned long)item,
- sizeof(struct btrfs_item),
- &right->map_token, &right->kaddr,
- &right->map_start, &right->map_len,
- KM_USER1);
- }
-
ioff = btrfs_item_offset(right, item);
btrfs_set_item_offset(right, item, ioff + rt_data_off);
}
- if (right->map_token) {
- unmap_extent_buffer(right, right->map_token, KM_USER1);
- right->map_token = NULL;
- }
-
btrfs_set_header_nritems(l, mid);
ret = 0;
btrfs_item_key(right, &disk_key, 0);
u32 ioff;
item = btrfs_item_nr(leaf, i);
- if (!leaf->map_token) {
- map_extent_buffer(leaf, (unsigned long)item,
- sizeof(struct btrfs_item),
- &leaf->map_token, &leaf->kaddr,
- &leaf->map_start, &leaf->map_len,
- KM_USER1);
- }
-
ioff = btrfs_item_offset(leaf, item);
btrfs_set_item_offset(leaf, item, ioff + size_diff);
}
- if (leaf->map_token) {
- unmap_extent_buffer(leaf, leaf->map_token, KM_USER1);
- leaf->map_token = NULL;
- }
-
/* shift the data */
if (from_end) {
memmove_extent_buffer(leaf, btrfs_leaf_data(leaf) +
u32 ioff;
item = btrfs_item_nr(leaf, i);
- if (!leaf->map_token) {
- map_extent_buffer(leaf, (unsigned long)item,
- sizeof(struct btrfs_item),
- &leaf->map_token, &leaf->kaddr,
- &leaf->map_start, &leaf->map_len,
- KM_USER1);
- }
ioff = btrfs_item_offset(leaf, item);
btrfs_set_item_offset(leaf, item, ioff - data_size);
}
- if (leaf->map_token) {
- unmap_extent_buffer(leaf, leaf->map_token, KM_USER1);
- leaf->map_token = NULL;
- }
-
/* shift the data */
memmove_extent_buffer(leaf, btrfs_leaf_data(leaf) +
data_end - data_size, btrfs_leaf_data(leaf) +
* item0..itemN ... dataN.offset..dataN.size .. data0.size
*/
/* first correct the data pointers */
- WARN_ON(leaf->map_token);
for (i = slot; i < nritems; i++) {
u32 ioff;
item = btrfs_item_nr(leaf, i);
- if (!leaf->map_token) {
- map_extent_buffer(leaf, (unsigned long)item,
- sizeof(struct btrfs_item),
- &leaf->map_token, &leaf->kaddr,
- &leaf->map_start, &leaf->map_len,
- KM_USER1);
- }
-
ioff = btrfs_item_offset(leaf, item);
btrfs_set_item_offset(leaf, item, ioff - total_data);
}
- if (leaf->map_token) {
- unmap_extent_buffer(leaf, leaf->map_token, KM_USER1);
- leaf->map_token = NULL;
- }
-
/* shift the items */
memmove_extent_buffer(leaf, btrfs_item_nr_offset(slot + nr),
btrfs_item_nr_offset(slot),
* item0..itemN ... dataN.offset..dataN.size .. data0.size
*/
/* first correct the data pointers */
- WARN_ON(leaf->map_token);
for (i = slot; i < nritems; i++) {
u32 ioff;
item = btrfs_item_nr(leaf, i);
- if (!leaf->map_token) {
- map_extent_buffer(leaf, (unsigned long)item,
- sizeof(struct btrfs_item),
- &leaf->map_token, &leaf->kaddr,
- &leaf->map_start, &leaf->map_len,
- KM_USER1);
- }
-
ioff = btrfs_item_offset(leaf, item);
btrfs_set_item_offset(leaf, item, ioff - total_data);
}
- if (leaf->map_token) {
- unmap_extent_buffer(leaf, leaf->map_token, KM_USER1);
- leaf->map_token = NULL;
- }
-
/* shift the items */
memmove_extent_buffer(leaf, btrfs_item_nr_offset(slot + nr),
btrfs_item_nr_offset(slot),
u32 ioff;
item = btrfs_item_nr(leaf, i);
- if (!leaf->map_token) {
- map_extent_buffer(leaf, (unsigned long)item,
- sizeof(struct btrfs_item),
- &leaf->map_token, &leaf->kaddr,
- &leaf->map_start, &leaf->map_len,
- KM_USER1);
- }
ioff = btrfs_item_offset(leaf, item);
btrfs_set_item_offset(leaf, item, ioff + dsize);
}
- if (leaf->map_token) {
- unmap_extent_buffer(leaf, leaf->map_token, KM_USER1);
- leaf->map_token = NULL;
- }
-
memmove_extent_buffer(leaf, btrfs_item_nr_offset(slot),
btrfs_item_nr_offset(slot + nr),
sizeof(struct btrfs_item) *
WARN_ON(!path->keep_locks);
again:
- cur = btrfs_lock_root_node(root);
+ cur = btrfs_read_lock_root_node(root);
level = btrfs_header_level(cur);
WARN_ON(path->nodes[level]);
path->nodes[level] = cur;
- path->locks[level] = 1;
+ path->locks[level] = BTRFS_READ_LOCK;
if (btrfs_header_generation(cur) < min_trans) {
ret = 1;
cur = read_node_slot(root, cur, slot);
BUG_ON(!cur);
- btrfs_tree_lock(cur);
+ btrfs_tree_read_lock(cur);
- path->locks[level - 1] = 1;
+ path->locks[level - 1] = BTRFS_READ_LOCK;
path->nodes[level - 1] = cur;
unlock_up(path, level, 1);
- btrfs_clear_path_blocking(path, NULL);
+ btrfs_clear_path_blocking(path, NULL, 0);
}
out:
if (ret == 0)
u32 nritems;
int ret;
int old_spinning = path->leave_spinning;
- int force_blocking = 0;
+ int next_rw_lock = 0;
nritems = btrfs_header_nritems(path->nodes[0]);
if (nritems == 0)
return 1;
- /*
- * we take the blocks in an order that upsets lockdep. Using
- * blocking mode is the only way around it.
- */
-#ifdef CONFIG_DEBUG_LOCK_ALLOC
- force_blocking = 1;
-#endif
-
btrfs_item_key_to_cpu(path->nodes[0], &key, nritems - 1);
again:
level = 1;
next = NULL;
+ next_rw_lock = 0;
btrfs_release_path(path);
path->keep_locks = 1;
-
- if (!force_blocking)
- path->leave_spinning = 1;
+ path->leave_spinning = 1;
ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
path->keep_locks = 0;
}
if (next) {
- btrfs_tree_unlock(next);
+ btrfs_tree_unlock_rw(next, next_rw_lock);
free_extent_buffer(next);
}
next = c;
+ next_rw_lock = path->locks[level];
ret = read_block_for_search(NULL, root, path, &next, level,
slot, &key);
if (ret == -EAGAIN)
}
if (!path->skip_locking) {
- ret = btrfs_try_spin_lock(next);
+ ret = btrfs_try_tree_read_lock(next);
if (!ret) {
btrfs_set_path_blocking(path);
- btrfs_tree_lock(next);
- if (!force_blocking)
- btrfs_clear_path_blocking(path, next);
+ btrfs_tree_read_lock(next);
+ btrfs_clear_path_blocking(path, next,
+ BTRFS_READ_LOCK);
}
- if (force_blocking)
- btrfs_set_lock_blocking(next);
+ next_rw_lock = BTRFS_READ_LOCK;
}
break;
}
level--;
c = path->nodes[level];
if (path->locks[level])
- btrfs_tree_unlock(c);
+ btrfs_tree_unlock_rw(c, path->locks[level]);
free_extent_buffer(c);
path->nodes[level] = next;
path->slots[level] = 0;
if (!path->skip_locking)
- path->locks[level] = 1;
-
+ path->locks[level] = next_rw_lock;
if (!level)
break;
}
if (!path->skip_locking) {
- btrfs_assert_tree_locked(path->nodes[level]);
- ret = btrfs_try_spin_lock(next);
+ ret = btrfs_try_tree_read_lock(next);
if (!ret) {
btrfs_set_path_blocking(path);
- btrfs_tree_lock(next);
- if (!force_blocking)
- btrfs_clear_path_blocking(path, next);
+ btrfs_tree_read_lock(next);
+ btrfs_clear_path_blocking(path, next,
+ BTRFS_READ_LOCK);
}
- if (force_blocking)
- btrfs_set_lock_blocking(next);
+ next_rw_lock = BTRFS_READ_LOCK;
}
}
ret = 0;
chunks for this space */
unsigned int chunk_alloc:1; /* set if we are allocating a chunk */
+ unsigned int flush:1; /* set if we are trying to make space */
+
unsigned int force_alloc; /* set if we need to force a chunk
alloc for this space */
struct list_head block_groups[BTRFS_NR_RAID_TYPES];
spinlock_t lock;
struct rw_semaphore groups_sem;
- atomic_t caching_threads;
+ wait_queue_head_t wait;
};
struct btrfs_block_rsv {
struct list_head list;
struct mutex mutex;
wait_queue_head_t wait;
+ struct btrfs_work work;
struct btrfs_block_group_cache *block_group;
u64 progress;
atomic_t count;
struct btrfs_workers endio_write_workers;
struct btrfs_workers endio_freespace_worker;
struct btrfs_workers submit_workers;
+ struct btrfs_workers caching_workers;
+
/*
* fixup workers take dirty pages that didn't properly go through
* the cow mechanism and make them safe to write. It happens
/* extent-tree.c */
static inline u64 btrfs_calc_trans_metadata_size(struct btrfs_root *root,
- int num_items)
+ unsigned num_items)
{
return (root->leafsize + root->nodesize * (BTRFS_MAX_LEVEL - 1)) *
3 * num_items;
void btrfs_clear_space_info_full(struct btrfs_fs_info *info);
int btrfs_check_data_free_space(struct inode *inode, u64 bytes);
void btrfs_free_reserved_data_space(struct inode *inode, u64 bytes);
-int btrfs_trans_reserve_metadata(struct btrfs_trans_handle *trans,
- struct btrfs_root *root,
- int num_items);
void btrfs_trans_release_metadata(struct btrfs_trans_handle *trans,
struct btrfs_root *root);
int btrfs_orphan_reserve_metadata(struct btrfs_trans_handle *trans,
void btrfs_free_path(struct btrfs_path *p);
void btrfs_set_path_blocking(struct btrfs_path *p);
void btrfs_clear_path_blocking(struct btrfs_path *p,
- struct extent_buffer *held);
+ struct extent_buffer *held, int held_rw);
void btrfs_unlock_up_safe(struct btrfs_path *p, int level);
int btrfs_del_items(struct btrfs_trans_handle *trans, struct btrfs_root *root,
}
/* reset all the locked nodes in the patch to spinning locks. */
- btrfs_clear_path_blocking(path, NULL);
+ btrfs_clear_path_blocking(path, NULL, 0);
/* insert the keys of the items */
ret = setup_items_for_insert(trans, root, path, keys, data_size,
data_size = sizeof(*dir_item) + name_len + data_len;
dir_item = insert_with_overflow(trans, root, path, &key, data_size,
name, name_len);
- /*
- * FIXME: at some point we should handle xattr's that are larger than
- * what we can fit in our leaf. We set location to NULL b/c we arent
- * pointing at anything else, that will change if we store the xattr
- * data in a separate inode.
- */
- BUG_ON(IS_ERR(dir_item));
+ if (IS_ERR(dir_item))
+ return PTR_ERR(dir_item);
memset(&location, 0, sizeof(location));
leaf = path->nodes[0];
struct btrfs_work work;
};
-/* These are used to set the lockdep class on the extent buffer locks.
- * The class is set by the readpage_end_io_hook after the buffer has
- * passed csum validation but before the pages are unlocked.
+/*
+ * Lockdep class keys for extent_buffer->lock's in this root. For a given
+ * eb, the lockdep key is determined by the btrfs_root it belongs to and
+ * the level the eb occupies in the tree.
+ *
+ * Different roots are used for different purposes and may nest inside each
+ * other and they require separate keysets. As lockdep keys should be
+ * static, assign keysets according to the purpose of the root as indicated
+ * by btrfs_root->objectid. This ensures that all special purpose roots
+ * have separate keysets.
*
- * The lockdep class is also set by btrfs_init_new_buffer on freshly
- * allocated blocks.
+ * Lock-nesting across peer nodes is always done with the immediate parent
+ * node locked thus preventing deadlock. As lockdep doesn't know this, use
+ * subclass to avoid triggering lockdep warning in such cases.
*
- * The class is based on the level in the tree block, which allows lockdep
- * to know that lower nodes nest inside the locks of higher nodes.
+ * The key is set by the readpage_end_io_hook after the buffer has passed
+ * csum validation but before the pages are unlocked. It is also set by
+ * btrfs_init_new_buffer on freshly allocated blocks.
*
- * We also add a check to make sure the highest level of the tree is
- * the same as our lockdep setup here. If BTRFS_MAX_LEVEL changes, this
- * code needs update as well.
+ * We also add a check to make sure the highest level of the tree is the
+ * same as our lockdep setup here. If BTRFS_MAX_LEVEL changes, this code
+ * needs update as well.
*/
#ifdef CONFIG_DEBUG_LOCK_ALLOC
# if BTRFS_MAX_LEVEL != 8
# error
# endif
-static struct lock_class_key btrfs_eb_class[BTRFS_MAX_LEVEL + 1];
-static const char *btrfs_eb_name[BTRFS_MAX_LEVEL + 1] = {
- /* leaf */
- "btrfs-extent-00",
- "btrfs-extent-01",
- "btrfs-extent-02",
- "btrfs-extent-03",
- "btrfs-extent-04",
- "btrfs-extent-05",
- "btrfs-extent-06",
- "btrfs-extent-07",
- /* highest possible level */
- "btrfs-extent-08",
+
+static struct btrfs_lockdep_keyset {
+ u64 id; /* root objectid */
+ const char *name_stem; /* lock name stem */
+ char names[BTRFS_MAX_LEVEL + 1][20];
+ struct lock_class_key keys[BTRFS_MAX_LEVEL + 1];
+} btrfs_lockdep_keysets[] = {
+ { .id = BTRFS_ROOT_TREE_OBJECTID, .name_stem = "root" },
+ { .id = BTRFS_EXTENT_TREE_OBJECTID, .name_stem = "extent" },
+ { .id = BTRFS_CHUNK_TREE_OBJECTID, .name_stem = "chunk" },
+ { .id = BTRFS_DEV_TREE_OBJECTID, .name_stem = "dev" },
+ { .id = BTRFS_FS_TREE_OBJECTID, .name_stem = "fs" },
+ { .id = BTRFS_CSUM_TREE_OBJECTID, .name_stem = "csum" },
+ { .id = BTRFS_ORPHAN_OBJECTID, .name_stem = "orphan" },
+ { .id = BTRFS_TREE_LOG_OBJECTID, .name_stem = "log" },
+ { .id = BTRFS_TREE_RELOC_OBJECTID, .name_stem = "treloc" },
+ { .id = BTRFS_DATA_RELOC_TREE_OBJECTID, .name_stem = "dreloc" },
+ { .id = 0, .name_stem = "tree" },
};
+
+void __init btrfs_init_lockdep(void)
+{
+ int i, j;
+
+ /* initialize lockdep class names */
+ for (i = 0; i < ARRAY_SIZE(btrfs_lockdep_keysets); i++) {
+ struct btrfs_lockdep_keyset *ks = &btrfs_lockdep_keysets[i];
+
+ for (j = 0; j < ARRAY_SIZE(ks->names); j++)
+ snprintf(ks->names[j], sizeof(ks->names[j]),
+ "btrfs-%s-%02d", ks->name_stem, j);
+ }
+}
+
+void btrfs_set_buffer_lockdep_class(u64 objectid, struct extent_buffer *eb,
+ int level)
+{
+ struct btrfs_lockdep_keyset *ks;
+
+ BUG_ON(level >= ARRAY_SIZE(ks->keys));
+
+ /* find the matching keyset, id 0 is the default entry */
+ for (ks = btrfs_lockdep_keysets; ks->id; ks++)
+ if (ks->id == objectid)
+ break;
+
+ lockdep_set_class_and_name(&eb->lock,
+ &ks->keys[level], ks->names[level]);
+}
+
#endif
/*
unsigned long len;
unsigned long cur_len;
unsigned long offset = BTRFS_CSUM_SIZE;
- char *map_token = NULL;
char *kaddr;
unsigned long map_start;
unsigned long map_len;
len = buf->len - offset;
while (len > 0) {
err = map_private_extent_buffer(buf, offset, 32,
- &map_token, &kaddr,
- &map_start, &map_len, KM_USER0);
+ &kaddr, &map_start, &map_len);
if (err)
return 1;
cur_len = min(len, map_len - (offset - map_start));
crc, cur_len);
len -= cur_len;
offset += cur_len;
- unmap_extent_buffer(buf, map_token, KM_USER0);
}
if (csum_size > sizeof(inline_result)) {
result = kzalloc(csum_size * sizeof(char), GFP_NOFS);
return 0;
}
-#ifdef CONFIG_DEBUG_LOCK_ALLOC
-void btrfs_set_buffer_lockdep_class(struct extent_buffer *eb, int level)
-{
- lockdep_set_class_and_name(&eb->lock,
- &btrfs_eb_class[level],
- btrfs_eb_name[level]);
-}
-#endif
-
static int btree_readpage_end_io_hook(struct page *page, u64 start, u64 end,
struct extent_state *state)
{
}
found_level = btrfs_header_level(eb);
- btrfs_set_buffer_lockdep_class(eb, found_level);
+ btrfs_set_buffer_lockdep_class(btrfs_header_owner(eb),
+ eb, found_level);
ret = csum_tree_block(root, eb, 1);
if (ret) {
goto fail_bdi;
}
- fs_info->btree_inode->i_mapping->flags &= ~__GFP_FS;
+ mapping_set_gfp_mask(fs_info->btree_inode->i_mapping, GFP_NOFS);
INIT_RADIX_TREE(&fs_info->fs_roots_radix, GFP_ATOMIC);
INIT_LIST_HEAD(&fs_info->trans_list);
fs_info->thread_pool_size),
&fs_info->generic_worker);
+ btrfs_init_workers(&fs_info->caching_workers, "cache",
+ 2, &fs_info->generic_worker);
+
/* a higher idle thresh on the submit workers makes it much more
* likely that bios will be send down in a sane order to the
* devices
btrfs_start_workers(&fs_info->endio_write_workers, 1);
btrfs_start_workers(&fs_info->endio_freespace_worker, 1);
btrfs_start_workers(&fs_info->delayed_workers, 1);
+ btrfs_start_workers(&fs_info->caching_workers, 1);
fs_info->bdi.ra_pages *= btrfs_super_num_devices(disk_super);
fs_info->bdi.ra_pages = max(fs_info->bdi.ra_pages,
btrfs_stop_workers(&fs_info->endio_freespace_worker);
btrfs_stop_workers(&fs_info->submit_workers);
btrfs_stop_workers(&fs_info->delayed_workers);
+ btrfs_stop_workers(&fs_info->caching_workers);
fail_alloc:
kfree(fs_info->delayed_root);
fail_iput:
btrfs_stop_workers(&fs_info->endio_freespace_worker);
btrfs_stop_workers(&fs_info->submit_workers);
btrfs_stop_workers(&fs_info->delayed_workers);
+ btrfs_stop_workers(&fs_info->caching_workers);
btrfs_close_devices(fs_info->fs_devices);
btrfs_mapping_tree_free(&fs_info->mapping_tree);
#ifdef CONFIG_DEBUG_LOCK_ALLOC
-void btrfs_set_buffer_lockdep_class(struct extent_buffer *eb, int level);
+void btrfs_init_lockdep(void);
+void btrfs_set_buffer_lockdep_class(u64 objectid,
+ struct extent_buffer *eb, int level);
#else
-static inline void btrfs_set_buffer_lockdep_class(struct extent_buffer *eb,
- int level)
+static inline void btrfs_init_lockdep(void)
+{ }
+static inline void btrfs_set_buffer_lockdep_class(u64 objectid,
+ struct extent_buffer *eb, int level)
{
}
#endif
return total_added;
}
-static int caching_kthread(void *data)
+static noinline void caching_thread(struct btrfs_work *work)
{
- struct btrfs_block_group_cache *block_group = data;
- struct btrfs_fs_info *fs_info = block_group->fs_info;
- struct btrfs_caching_control *caching_ctl = block_group->caching_ctl;
- struct btrfs_root *extent_root = fs_info->extent_root;
+ struct btrfs_block_group_cache *block_group;
+ struct btrfs_fs_info *fs_info;
+ struct btrfs_caching_control *caching_ctl;
+ struct btrfs_root *extent_root;
struct btrfs_path *path;
struct extent_buffer *leaf;
struct btrfs_key key;
u32 nritems;
int ret = 0;
+ caching_ctl = container_of(work, struct btrfs_caching_control, work);
+ block_group = caching_ctl->block_group;
+ fs_info = block_group->fs_info;
+ extent_root = fs_info->extent_root;
+
path = btrfs_alloc_path();
if (!path)
- return -ENOMEM;
+ goto out;
last = max_t(u64, block_group->key.objectid, BTRFS_SUPER_INFO_OFFSET);
free_excluded_extents(extent_root, block_group);
mutex_unlock(&caching_ctl->mutex);
+out:
wake_up(&caching_ctl->wait);
put_caching_control(caching_ctl);
- atomic_dec(&block_group->space_info->caching_threads);
btrfs_put_block_group(block_group);
-
- return 0;
}
static int cache_block_group(struct btrfs_block_group_cache *cache,
{
struct btrfs_fs_info *fs_info = cache->fs_info;
struct btrfs_caching_control *caching_ctl;
- struct task_struct *tsk;
int ret = 0;
smp_mb();
caching_ctl->progress = cache->key.objectid;
/* one for caching kthread, one for caching block group list */
atomic_set(&caching_ctl->count, 2);
+ caching_ctl->work.func = caching_thread;
spin_lock(&cache->lock);
if (cache->cached != BTRFS_CACHE_NO) {
list_add_tail(&caching_ctl->list, &fs_info->caching_block_groups);
up_write(&fs_info->extent_commit_sem);
- atomic_inc(&cache->space_info->caching_threads);
btrfs_get_block_group(cache);
- tsk = kthread_run(caching_kthread, cache, "btrfs-cache-%llu\n",
- cache->key.objectid);
- if (IS_ERR(tsk)) {
- ret = PTR_ERR(tsk);
- printk(KERN_ERR "error running thread %d\n", ret);
- BUG();
- }
+ btrfs_queue_worker(&fs_info->caching_workers, &caching_ctl->work);
return ret;
}
found->full = 0;
found->force_alloc = CHUNK_ALLOC_NO_FORCE;
found->chunk_alloc = 0;
+ found->flush = 0;
+ init_waitqueue_head(&found->wait);
*space_info = found;
list_add_rcu(&found->list, &info->space_info);
- atomic_set(&found->caching_threads, 0);
return 0;
}
if (reserved == 0)
return 0;
+ smp_mb();
+ if (root->fs_info->delalloc_bytes == 0) {
+ if (trans)
+ return 0;
+ btrfs_wait_ordered_extents(root, 0, 0);
+ return 0;
+ }
+
max_reclaim = min(reserved, to_reclaim);
while (loops < 1024) {
}
}
+ if (reclaimed >= to_reclaim && !trans)
+ btrfs_wait_ordered_extents(root, 0, 0);
return reclaimed >= to_reclaim;
}
u64 num_bytes = orig_bytes;
int retries = 0;
int ret = 0;
- bool reserved = false;
bool committed = false;
+ bool flushing = false;
again:
- ret = -ENOSPC;
- if (reserved)
- num_bytes = 0;
-
+ ret = 0;
spin_lock(&space_info->lock);
+ /*
+ * We only want to wait if somebody other than us is flushing and we are
+ * actually alloed to flush.
+ */
+ while (flush && !flushing && space_info->flush) {
+ spin_unlock(&space_info->lock);
+ /*
+ * If we have a trans handle we can't wait because the flusher
+ * may have to commit the transaction, which would mean we would
+ * deadlock since we are waiting for the flusher to finish, but
+ * hold the current transaction open.
+ */
+ if (trans)
+ return -EAGAIN;
+ ret = wait_event_interruptible(space_info->wait,
+ !space_info->flush);
+ /* Must have been interrupted, return */
+ if (ret)
+ return -EINTR;
+
+ spin_lock(&space_info->lock);
+ }
+
+ ret = -ENOSPC;
unused = space_info->bytes_used + space_info->bytes_reserved +
space_info->bytes_pinned + space_info->bytes_readonly +
space_info->bytes_may_use;
if (unused <= space_info->total_bytes) {
unused = space_info->total_bytes - unused;
if (unused >= num_bytes) {
- if (!reserved)
- space_info->bytes_reserved += orig_bytes;
+ space_info->bytes_reserved += orig_bytes;
ret = 0;
} else {
/*
* to reclaim space we can actually use it instead of somebody else
* stealing it from us.
*/
- if (ret && !reserved) {
- space_info->bytes_reserved += orig_bytes;
- reserved = true;
+ if (ret && flush) {
+ flushing = true;
+ space_info->flush = 1;
}
spin_unlock(&space_info->lock);
- if (!ret)
- return 0;
-
- if (!flush)
+ if (!ret || !flush)
goto out;
/*
* metadata until after the IO is completed.
*/
ret = shrink_delalloc(trans, root, num_bytes, 1);
- if (ret > 0)
- return 0;
- else if (ret < 0)
+ if (ret < 0)
goto out;
+ ret = 0;
+
/*
* So if we were overcommitted it's possible that somebody else flushed
* out enough space and we simply didn't have enough space to reclaim,
goto again;
}
- spin_lock(&space_info->lock);
/*
* Not enough space to be reclaimed, don't bother committing the
* transaction.
*/
+ spin_lock(&space_info->lock);
if (space_info->bytes_pinned < orig_bytes)
ret = -ENOSPC;
spin_unlock(&space_info->lock);
goto out;
ret = -EAGAIN;
- if (trans || committed)
+ if (trans)
goto out;
ret = -ENOSPC;
+ if (committed)
+ goto out;
+
trans = btrfs_join_transaction(root);
if (IS_ERR(trans))
goto out;
}
out:
- if (reserved) {
+ if (flushing) {
spin_lock(&space_info->lock);
- space_info->bytes_reserved -= orig_bytes;
+ space_info->flush = 0;
+ wake_up_all(&space_info->wait);
spin_unlock(&space_info->lock);
}
-
return ret;
}
if (commit_trans) {
if (trans)
return -EAGAIN;
-
trans = btrfs_join_transaction(root);
BUG_ON(IS_ERR(trans));
ret = btrfs_commit_transaction(trans, root);
return 0;
}
-int btrfs_trans_reserve_metadata(struct btrfs_trans_handle *trans,
- struct btrfs_root *root,
- int num_items)
-{
- u64 num_bytes;
- int ret;
-
- if (num_items == 0 || root->fs_info->chunk_root == root)
- return 0;
-
- num_bytes = btrfs_calc_trans_metadata_size(root, num_items);
- ret = btrfs_block_rsv_add(trans, root, &root->fs_info->trans_block_rsv,
- num_bytes);
- if (!ret) {
- trans->bytes_reserved += num_bytes;
- trans->block_rsv = &root->fs_info->trans_block_rsv;
- }
- return ret;
-}
-
void btrfs_trans_release_metadata(struct btrfs_trans_handle *trans,
struct btrfs_root *root)
{
return block_rsv_migrate_bytes(src_rsv, dst_rsv, num_bytes);
}
+static unsigned drop_outstanding_extent(struct inode *inode)
+{
+ unsigned dropped_extents = 0;
+
+ spin_lock(&BTRFS_I(inode)->lock);
+ BUG_ON(!BTRFS_I(inode)->outstanding_extents);
+ BTRFS_I(inode)->outstanding_extents--;
+
+ /*
+ * If we have more or the same amount of outsanding extents than we have
+ * reserved then we need to leave the reserved extents count alone.
+ */
+ if (BTRFS_I(inode)->outstanding_extents >=
+ BTRFS_I(inode)->reserved_extents)
+ goto out;
+
+ dropped_extents = BTRFS_I(inode)->reserved_extents -
+ BTRFS_I(inode)->outstanding_extents;
+ BTRFS_I(inode)->reserved_extents -= dropped_extents;
+out:
+ spin_unlock(&BTRFS_I(inode)->lock);
+ return dropped_extents;
+}
+
static u64 calc_csum_metadata_size(struct inode *inode, u64 num_bytes)
{
return num_bytes >>= 3;
{
struct btrfs_root *root = BTRFS_I(inode)->root;
struct btrfs_block_rsv *block_rsv = &root->fs_info->delalloc_block_rsv;
- u64 to_reserve;
- int nr_extents;
- int reserved_extents;
+ u64 to_reserve = 0;
+ unsigned nr_extents = 0;
int ret;
if (btrfs_transaction_in_commit(root->fs_info))
num_bytes = ALIGN(num_bytes, root->sectorsize);
- nr_extents = atomic_read(&BTRFS_I(inode)->outstanding_extents) + 1;
- reserved_extents = atomic_read(&BTRFS_I(inode)->reserved_extents);
+ spin_lock(&BTRFS_I(inode)->lock);
+ BTRFS_I(inode)->outstanding_extents++;
+
+ if (BTRFS_I(inode)->outstanding_extents >
+ BTRFS_I(inode)->reserved_extents) {
+ nr_extents = BTRFS_I(inode)->outstanding_extents -
+ BTRFS_I(inode)->reserved_extents;
+ BTRFS_I(inode)->reserved_extents += nr_extents;
- if (nr_extents > reserved_extents) {
- nr_extents -= reserved_extents;
to_reserve = btrfs_calc_trans_metadata_size(root, nr_extents);
- } else {
- nr_extents = 0;
- to_reserve = 0;
}
+ spin_unlock(&BTRFS_I(inode)->lock);
to_reserve += calc_csum_metadata_size(inode, num_bytes);
ret = reserve_metadata_bytes(NULL, root, block_rsv, to_reserve, 1);
- if (ret)
+ if (ret) {
+ unsigned dropped;
+ /*
+ * We don't need the return value since our reservation failed,
+ * we just need to clean up our counter.
+ */
+ dropped = drop_outstanding_extent(inode);
+ WARN_ON(dropped > 1);
return ret;
-
- atomic_add(nr_extents, &BTRFS_I(inode)->reserved_extents);
- atomic_inc(&BTRFS_I(inode)->outstanding_extents);
+ }
block_rsv_add_bytes(block_rsv, to_reserve, 1);
- if (block_rsv->size > 512 * 1024 * 1024)
- shrink_delalloc(NULL, root, to_reserve, 0);
-
return 0;
}
void btrfs_delalloc_release_metadata(struct inode *inode, u64 num_bytes)
{
struct btrfs_root *root = BTRFS_I(inode)->root;
- u64 to_free;
- int nr_extents;
- int reserved_extents;
+ u64 to_free = 0;
+ unsigned dropped;
num_bytes = ALIGN(num_bytes, root->sectorsize);
- atomic_dec(&BTRFS_I(inode)->outstanding_extents);
- WARN_ON(atomic_read(&BTRFS_I(inode)->outstanding_extents) < 0);
-
- reserved_extents = atomic_read(&BTRFS_I(inode)->reserved_extents);
- do {
- int old, new;
-
- nr_extents = atomic_read(&BTRFS_I(inode)->outstanding_extents);
- if (nr_extents >= reserved_extents) {
- nr_extents = 0;
- break;
- }
- old = reserved_extents;
- nr_extents = reserved_extents - nr_extents;
- new = reserved_extents - nr_extents;
- old = atomic_cmpxchg(&BTRFS_I(inode)->reserved_extents,
- reserved_extents, new);
- if (likely(old == reserved_extents))
- break;
- reserved_extents = old;
- } while (1);
+ dropped = drop_outstanding_extent(inode);
to_free = calc_csum_metadata_size(inode, num_bytes);
- if (nr_extents > 0)
- to_free += btrfs_calc_trans_metadata_size(root, nr_extents);
+ if (dropped > 0)
+ to_free += btrfs_calc_trans_metadata_size(root, dropped);
btrfs_block_rsv_release(root, &root->fs_info->delalloc_block_rsv,
to_free);
}
/*
- * We only want to start kthread caching if we are at
- * the point where we will wait for caching to make
- * progress, or if our ideal search is over and we've
- * found somebody to start caching.
+ * The caching workers are limited to 2 threads, so we
+ * can queue as much work as we care to.
*/
- if (loop > LOOP_CACHING_NOWAIT ||
- (loop > LOOP_FIND_IDEAL &&
- atomic_read(&space_info->caching_threads) < 2)) {
+ if (loop > LOOP_FIND_IDEAL) {
ret = cache_block_group(block_group, trans,
orig_root, 0);
BUG_ON(ret);
if (loop == LOOP_FIND_IDEAL && found_uncached_bg) {
found_uncached_bg = false;
loop++;
- if (!ideal_cache_percent &&
- atomic_read(&space_info->caching_threads))
+ if (!ideal_cache_percent)
goto search;
/*
if (!buf)
return ERR_PTR(-ENOMEM);
btrfs_set_header_generation(buf, trans->transid);
- btrfs_set_buffer_lockdep_class(buf, level);
+ btrfs_set_buffer_lockdep_class(root->root_key.objectid, buf, level);
btrfs_tree_lock(buf);
clean_tree_block(trans, root, buf);
return 1;
if (path->locks[level] && !wc->keep_locks) {
- btrfs_tree_unlock(eb);
+ btrfs_tree_unlock_rw(eb, path->locks[level]);
path->locks[level] = 0;
}
return 0;
* keep the tree lock
*/
if (path->locks[level] && level > 0) {
- btrfs_tree_unlock(eb);
+ btrfs_tree_unlock_rw(eb, path->locks[level]);
path->locks[level] = 0;
}
return 0;
BUG_ON(level != btrfs_header_level(next));
path->nodes[level] = next;
path->slots[level] = 0;
- path->locks[level] = 1;
+ path->locks[level] = BTRFS_WRITE_LOCK_BLOCKING;
wc->level = level;
if (wc->level == 1)
wc->reada_slot = 0;
BUG_ON(level == 0);
btrfs_tree_lock(eb);
btrfs_set_lock_blocking(eb);
- path->locks[level] = 1;
+ path->locks[level] = BTRFS_WRITE_LOCK_BLOCKING;
ret = btrfs_lookup_extent_info(trans, root,
eb->start, eb->len,
BUG_ON(ret);
BUG_ON(wc->refs[level] == 0);
if (wc->refs[level] == 1) {
- btrfs_tree_unlock(eb);
- path->locks[level] = 0;
+ btrfs_tree_unlock_rw(eb, path->locks[level]);
return 1;
}
}
btrfs_header_generation(eb) == trans->transid) {
btrfs_tree_lock(eb);
btrfs_set_lock_blocking(eb);
- path->locks[level] = 1;
+ path->locks[level] = BTRFS_WRITE_LOCK_BLOCKING;
}
clean_tree_block(trans, root, eb);
}
return 0;
if (path->locks[level]) {
- btrfs_tree_unlock(path->nodes[level]);
+ btrfs_tree_unlock_rw(path->nodes[level],
+ path->locks[level]);
path->locks[level] = 0;
}
free_extent_buffer(path->nodes[level]);
path->nodes[level] = btrfs_lock_root_node(root);
btrfs_set_lock_blocking(path->nodes[level]);
path->slots[level] = 0;
- path->locks[level] = 1;
+ path->locks[level] = BTRFS_WRITE_LOCK_BLOCKING;
memset(&wc->update_progress, 0,
sizeof(wc->update_progress));
} else {
level = btrfs_header_level(node);
path->nodes[level] = node;
path->slots[level] = 0;
- path->locks[level] = 1;
+ path->locks[level] = BTRFS_WRITE_LOCK_BLOCKING;
wc->refs[parent_level] = 1;
wc->flags[parent_level] = BTRFS_BLOCK_FLAG_FULL_BACKREF;
return flags;
}
-static int set_block_group_ro(struct btrfs_block_group_cache *cache)
+static int set_block_group_ro(struct btrfs_block_group_cache *cache, int force)
{
struct btrfs_space_info *sinfo = cache->space_info;
u64 num_bytes;
+ u64 min_allocable_bytes;
int ret = -ENOSPC;
if (cache->ro)
return 0;
+ /*
+ * We need some metadata space and system metadata space for
+ * allocating chunks in some corner cases until we force to set
+ * it to be readonly.
+ */
+ if ((sinfo->flags &
+ (BTRFS_BLOCK_GROUP_SYSTEM | BTRFS_BLOCK_GROUP_METADATA)) &&
+ !force)
+ min_allocable_bytes = 1 * 1024 * 1024;
+ else
+ min_allocable_bytes = 0;
+
spin_lock(&sinfo->lock);
spin_lock(&cache->lock);
num_bytes = cache->key.offset - cache->reserved - cache->pinned -
if (sinfo->bytes_used + sinfo->bytes_reserved + sinfo->bytes_pinned +
sinfo->bytes_may_use + sinfo->bytes_readonly +
- cache->reserved_pinned + num_bytes <= sinfo->total_bytes) {
+ cache->reserved_pinned + num_bytes + min_allocable_bytes <=
+ sinfo->total_bytes) {
sinfo->bytes_readonly += num_bytes;
sinfo->bytes_reserved += cache->reserved_pinned;
cache->reserved_pinned = 0;
do_chunk_alloc(trans, root, 2 * 1024 * 1024, alloc_flags,
CHUNK_ALLOC_FORCE);
- ret = set_block_group_ro(cache);
+ ret = set_block_group_ro(cache, 0);
if (!ret)
goto out;
alloc_flags = get_alloc_profile(root, cache->space_info->flags);
CHUNK_ALLOC_FORCE);
if (ret < 0)
goto out;
- ret = set_block_group_ro(cache);
+ ret = set_block_group_ro(cache, 0);
out:
btrfs_end_transaction(trans, root);
return ret;
set_avail_alloc_bits(root->fs_info, cache->flags);
if (btrfs_chunk_readonly(root, cache->key.objectid))
- set_block_group_ro(cache);
+ set_block_group_ro(cache, 1);
}
list_for_each_entry_rcu(space_info, &root->fs_info->space_info, list) {
* mirrored block groups.
*/
list_for_each_entry(cache, &space_info->block_groups[3], list)
- set_block_group_ro(cache);
+ set_block_group_ro(cache, 1);
list_for_each_entry(cache, &space_info->block_groups[4], list)
- set_block_group_ro(cache);
+ set_block_group_ro(cache, 1);
}
init_global_block_rsv(info);
if (other->start == state->end + 1 &&
other->state == state->state) {
merge_cb(tree, state, other);
- other->start = state->start;
- state->tree = NULL;
- rb_erase(&state->rb_node, &tree->state);
- free_extent_state(state);
- state = NULL;
+ state->end = other->end;
+ other->tree = NULL;
+ rb_erase(&other->rb_node, &tree->state);
+ free_extent_state(other);
}
}
"%llu %llu\n", (unsigned long long)found->start,
(unsigned long long)found->end,
(unsigned long long)start, (unsigned long long)end);
- free_extent_state(state);
return -EEXIST;
}
state->tree = tree;
cached_state = NULL;
}
- if (cached && cached->tree && cached->start == start) {
+ if (cached && cached->tree && cached->start <= start &&
+ cached->end > start) {
if (clear)
atomic_dec(&cached->refs);
state = cached;
spin_lock(&tree->lock);
if (cached_state && *cached_state) {
state = *cached_state;
- if (state->start == start && state->tree) {
+ if (state->start <= start && state->end > start &&
+ state->tree) {
node = &state->rb_node;
goto hit_next;
}
if (err)
goto out;
- next_node = rb_next(node);
cache_state(state, cached_state);
merge_state(tree, state);
if (last_end == (u64)-1)
goto out;
start = last_end + 1;
+ next_node = rb_next(&state->rb_node);
if (next_node && start < end && prealloc && !need_resched()) {
state = rb_entry(next_node, struct extent_state,
rb_node);
* Avoid to free 'prealloc' if it can be merged with
* the later extent.
*/
- atomic_inc(&prealloc->refs);
err = insert_state(tree, prealloc, start, this_end,
&bits);
BUG_ON(err == -EEXIST);
goto out;
}
cache_state(prealloc, cached_state);
- free_extent_state(prealloc);
prealloc = NULL;
start = this_end + 1;
goto search_again;
int bitset = 0;
spin_lock(&tree->lock);
- if (cached && cached->tree && cached->start == start)
+ if (cached && cached->tree && cached->start <= start &&
+ cached->end > start)
node = &cached->rb_node;
else
node = tree_search(tree, start);
pgoff_t index;
pgoff_t end; /* Inclusive */
int scanned = 0;
+ int tag;
pagevec_init(&pvec, 0);
if (wbc->range_cyclic) {
end = wbc->range_end >> PAGE_CACHE_SHIFT;
scanned = 1;
}
+ if (wbc->sync_mode == WB_SYNC_ALL)
+ tag = PAGECACHE_TAG_TOWRITE;
+ else
+ tag = PAGECACHE_TAG_DIRTY;
retry:
+ if (wbc->sync_mode == WB_SYNC_ALL)
+ tag_pages_for_writeback(mapping, index, end);
while (!done && !nr_to_write_done && (index <= end) &&
- (nr_pages = pagevec_lookup_tag(&pvec, mapping, &index,
- PAGECACHE_TAG_DIRTY, min(end - index,
- (pgoff_t)PAGEVEC_SIZE-1) + 1))) {
+ (nr_pages = pagevec_lookup_tag(&pvec, mapping, &index, tag,
+ min(end - index, (pgoff_t)PAGEVEC_SIZE-1) + 1))) {
unsigned i;
scanned = 1;
return NULL;
eb->start = start;
eb->len = len;
- spin_lock_init(&eb->lock);
- init_waitqueue_head(&eb->lock_wq);
+ rwlock_init(&eb->lock);
+ atomic_set(&eb->write_locks, 0);
+ atomic_set(&eb->read_locks, 0);
+ atomic_set(&eb->blocking_readers, 0);
+ atomic_set(&eb->blocking_writers, 0);
+ atomic_set(&eb->spinning_readers, 0);
+ atomic_set(&eb->spinning_writers, 0);
+ init_waitqueue_head(&eb->write_lock_wq);
+ init_waitqueue_head(&eb->read_lock_wq);
#if LEAK_DEBUG
spin_lock_irqsave(&leak_lock, flags);
i = 0;
}
for (; i < num_pages; i++, index++) {
- p = find_or_create_page(mapping, index, GFP_NOFS | __GFP_HIGHMEM);
+ p = find_or_create_page(mapping, index, GFP_NOFS);
if (!p) {
WARN_ON(1);
goto free_eb;
return was_dirty;
}
+static int __eb_straddles_pages(u64 start, u64 len)
+{
+ if (len < PAGE_CACHE_SIZE)
+ return 1;
+ if (start & (PAGE_CACHE_SIZE - 1))
+ return 1;
+ if ((start + len) & (PAGE_CACHE_SIZE - 1))
+ return 1;
+ return 0;
+}
+
+static int eb_straddles_pages(struct extent_buffer *eb)
+{
+ return __eb_straddles_pages(eb->start, eb->len);
+}
+
int clear_extent_buffer_uptodate(struct extent_io_tree *tree,
struct extent_buffer *eb,
struct extent_state **cached_state)
num_pages = num_extent_pages(eb->start, eb->len);
clear_bit(EXTENT_BUFFER_UPTODATE, &eb->bflags);
- clear_extent_uptodate(tree, eb->start, eb->start + eb->len - 1,
- cached_state, GFP_NOFS);
+ if (eb_straddles_pages(eb)) {
+ clear_extent_uptodate(tree, eb->start, eb->start + eb->len - 1,
+ cached_state, GFP_NOFS);
+ }
for (i = 0; i < num_pages; i++) {
page = extent_buffer_page(eb, i);
if (page)
num_pages = num_extent_pages(eb->start, eb->len);
- set_extent_uptodate(tree, eb->start, eb->start + eb->len - 1,
- NULL, GFP_NOFS);
+ if (eb_straddles_pages(eb)) {
+ set_extent_uptodate(tree, eb->start, eb->start + eb->len - 1,
+ NULL, GFP_NOFS);
+ }
for (i = 0; i < num_pages; i++) {
page = extent_buffer_page(eb, i);
if ((i == 0 && (eb->start & (PAGE_CACHE_SIZE - 1))) ||
int uptodate;
unsigned long index;
- ret = test_range_bit(tree, start, end, EXTENT_UPTODATE, 1, NULL);
- if (ret)
- return 1;
+ if (__eb_straddles_pages(start, end - start + 1)) {
+ ret = test_range_bit(tree, start, end,
+ EXTENT_UPTODATE, 1, NULL);
+ if (ret)
+ return 1;
+ }
while (start <= end) {
index = start >> PAGE_CACHE_SHIFT;
page = find_get_page(tree->mapping, index);
if (test_bit(EXTENT_BUFFER_UPTODATE, &eb->bflags))
return 1;
- ret = test_range_bit(tree, eb->start, eb->start + eb->len - 1,
- EXTENT_UPTODATE, 1, cached_state);
- if (ret)
- return ret;
+ if (eb_straddles_pages(eb)) {
+ ret = test_range_bit(tree, eb->start, eb->start + eb->len - 1,
+ EXTENT_UPTODATE, 1, cached_state);
+ if (ret)
+ return ret;
+ }
num_pages = num_extent_pages(eb->start, eb->len);
for (i = 0; i < num_pages; i++) {
if (test_bit(EXTENT_BUFFER_UPTODATE, &eb->bflags))
return 0;
- if (test_range_bit(tree, eb->start, eb->start + eb->len - 1,
- EXTENT_UPTODATE, 1, NULL)) {
- return 0;
+ if (eb_straddles_pages(eb)) {
+ if (test_range_bit(tree, eb->start, eb->start + eb->len - 1,
+ EXTENT_UPTODATE, 1, NULL)) {
+ return 0;
+ }
}
if (start) {
page = extent_buffer_page(eb, i);
cur = min(len, (PAGE_CACHE_SIZE - offset));
- kaddr = kmap_atomic(page, KM_USER1);
+ kaddr = page_address(page);
memcpy(dst, kaddr + offset, cur);
- kunmap_atomic(kaddr, KM_USER1);
dst += cur;
len -= cur;
}
int map_private_extent_buffer(struct extent_buffer *eb, unsigned long start,
- unsigned long min_len, char **token, char **map,
+ unsigned long min_len, char **map,
unsigned long *map_start,
- unsigned long *map_len, int km)
+ unsigned long *map_len)
{
size_t offset = start & (PAGE_CACHE_SIZE - 1);
char *kaddr;
}
p = extent_buffer_page(eb, i);
- kaddr = kmap_atomic(p, km);
- *token = kaddr;
+ kaddr = page_address(p);
*map = kaddr + offset;
*map_len = PAGE_CACHE_SIZE - offset;
return 0;
}
-int map_extent_buffer(struct extent_buffer *eb, unsigned long start,
- unsigned long min_len,
- char **token, char **map,
- unsigned long *map_start,
- unsigned long *map_len, int km)
-{
- int err;
- int save = 0;
- if (eb->map_token) {
- unmap_extent_buffer(eb, eb->map_token, km);
- eb->map_token = NULL;
- save = 1;
- }
- err = map_private_extent_buffer(eb, start, min_len, token, map,
- map_start, map_len, km);
- if (!err && save) {
- eb->map_token = *token;
- eb->kaddr = *map;
- eb->map_start = *map_start;
- eb->map_len = *map_len;
- }
- return err;
-}
-
-void unmap_extent_buffer(struct extent_buffer *eb, char *token, int km)
-{
- kunmap_atomic(token, km);
-}
-
int memcmp_extent_buffer(struct extent_buffer *eb, const void *ptrv,
unsigned long start,
unsigned long len)
cur = min(len, (PAGE_CACHE_SIZE - offset));
- kaddr = kmap_atomic(page, KM_USER0);
+ kaddr = page_address(page);
ret = memcmp(ptr, kaddr + offset, cur);
- kunmap_atomic(kaddr, KM_USER0);
if (ret)
break;
WARN_ON(!PageUptodate(page));
cur = min(len, PAGE_CACHE_SIZE - offset);
- kaddr = kmap_atomic(page, KM_USER1);
+ kaddr = page_address(page);
memcpy(kaddr + offset, src, cur);
- kunmap_atomic(kaddr, KM_USER1);
src += cur;
len -= cur;
WARN_ON(!PageUptodate(page));
cur = min(len, PAGE_CACHE_SIZE - offset);
- kaddr = kmap_atomic(page, KM_USER0);
+ kaddr = page_address(page);
memset(kaddr + offset, c, cur);
- kunmap_atomic(kaddr, KM_USER0);
len -= cur;
offset = 0;
cur = min(len, (unsigned long)(PAGE_CACHE_SIZE - offset));
- kaddr = kmap_atomic(page, KM_USER0);
+ kaddr = page_address(page);
read_extent_buffer(src, kaddr + offset, src_offset, cur);
- kunmap_atomic(kaddr, KM_USER0);
src_offset += cur;
len -= cur;
unsigned long dst_off, unsigned long src_off,
unsigned long len)
{
- char *dst_kaddr = kmap_atomic(dst_page, KM_USER0);
+ char *dst_kaddr = page_address(dst_page);
if (dst_page == src_page) {
memmove(dst_kaddr + dst_off, dst_kaddr + src_off, len);
} else {
- char *src_kaddr = kmap_atomic(src_page, KM_USER1);
+ char *src_kaddr = page_address(src_page);
char *p = dst_kaddr + dst_off + len;
char *s = src_kaddr + src_off + len;
while (len--)
*--p = *--s;
-
- kunmap_atomic(src_kaddr, KM_USER1);
}
- kunmap_atomic(dst_kaddr, KM_USER0);
}
static inline bool areas_overlap(unsigned long src, unsigned long dst, unsigned long len)
unsigned long dst_off, unsigned long src_off,
unsigned long len)
{
- char *dst_kaddr = kmap_atomic(dst_page, KM_USER0);
+ char *dst_kaddr = page_address(dst_page);
char *src_kaddr;
if (dst_page != src_page) {
- src_kaddr = kmap_atomic(src_page, KM_USER1);
+ src_kaddr = page_address(src_page);
} else {
src_kaddr = dst_kaddr;
BUG_ON(areas_overlap(src_off, dst_off, len));
}
memcpy(dst_kaddr + dst_off, src_kaddr + src_off, len);
- kunmap_atomic(dst_kaddr, KM_USER0);
- if (dst_page != src_page)
- kunmap_atomic(src_kaddr, KM_USER1);
}
void memcpy_extent_buffer(struct extent_buffer *dst, unsigned long dst_offset,
struct extent_buffer {
u64 start;
unsigned long len;
- char *map_token;
- char *kaddr;
unsigned long map_start;
unsigned long map_len;
struct page *first_page;
struct rcu_head rcu_head;
atomic_t refs;
- /* the spinlock is used to protect most operations */
- spinlock_t lock;
+ /* count of read lock holders on the extent buffer */
+ atomic_t write_locks;
+ atomic_t read_locks;
+ atomic_t blocking_writers;
+ atomic_t blocking_readers;
+ atomic_t spinning_readers;
+ atomic_t spinning_writers;
+
+ /* protects write locks */
+ rwlock_t lock;
- /*
- * when we keep the lock held while blocking, waiters go onto
- * the wq
+ /* readers use lock_wq while they wait for the write
+ * lock holders to unlock
*/
- wait_queue_head_t lock_wq;
+ wait_queue_head_t write_lock_wq;
+
+ /* writers use read_lock_wq while they wait for readers
+ * to unlock
+ */
+ wait_queue_head_t read_lock_wq;
};
static inline void extent_set_compress_type(unsigned long *bio_flags,
int extent_buffer_uptodate(struct extent_io_tree *tree,
struct extent_buffer *eb,
struct extent_state *cached_state);
-int map_extent_buffer(struct extent_buffer *eb, unsigned long offset,
- unsigned long min_len, char **token, char **map,
- unsigned long *map_start,
- unsigned long *map_len, int km);
int map_private_extent_buffer(struct extent_buffer *eb, unsigned long offset,
- unsigned long min_len, char **token, char **map,
+ unsigned long min_len, char **map,
unsigned long *map_start,
- unsigned long *map_len, int km);
-void unmap_extent_buffer(struct extent_buffer *eb, char *token, int km);
+ unsigned long *map_len);
int extent_range_uptodate(struct extent_io_tree *tree,
u64 start, u64 end);
int extent_clear_unlock_delalloc(struct inode *inode,
WARN_ON(bio->bi_vcnt <= 0);
+ /*
+ * the free space stuff is only read when it hasn't been
+ * updated in the current transaction. So, we can safely
+ * read from the commit root and sidestep a nasty deadlock
+ * between reading the free space cache and updating the csum tree.
+ */
+ if (btrfs_is_free_space_inode(root, inode))
+ path->search_commit_root = 1;
+
disk_bytenr = (u64)bio->bi_sector << 9;
if (dio)
offset = logical_offset;
struct btrfs_sector_sum *sector_sum;
u32 nritems;
u32 ins_size;
- char *eb_map;
- char *eb_token;
- unsigned long map_len;
- unsigned long map_start;
u16 csum_size =
btrfs_super_csum_size(&root->fs_info->super_copy);
item_end = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_csum_item);
item_end = (struct btrfs_csum_item *)((unsigned char *)item_end +
btrfs_item_size_nr(leaf, path->slots[0]));
- eb_token = NULL;
next_sector:
- if (!eb_token ||
- (unsigned long)item + csum_size >= map_start + map_len) {
- int err;
-
- if (eb_token)
- unmap_extent_buffer(leaf, eb_token, KM_USER1);
- eb_token = NULL;
- err = map_private_extent_buffer(leaf, (unsigned long)item,
- csum_size,
- &eb_token, &eb_map,
- &map_start, &map_len, KM_USER1);
- if (err)
- eb_token = NULL;
- }
- if (eb_token) {
- memcpy(eb_token + ((unsigned long)item & (PAGE_CACHE_SIZE - 1)),
- §or_sum->sum, csum_size);
- } else {
- write_extent_buffer(leaf, §or_sum->sum,
- (unsigned long)item, csum_size);
- }
+ write_extent_buffer(leaf, §or_sum->sum, (unsigned long)item, csum_size);
total_bytes += root->sectorsize;
sector_sum++;
goto next_sector;
}
}
- if (eb_token) {
- unmap_extent_buffer(leaf, eb_token, KM_USER1);
- eb_token = NULL;
- }
+
btrfs_mark_buffer_dirty(path->nodes[0]);
if (total_bytes < sums->len) {
btrfs_release_path(path);
again:
for (i = 0; i < num_pages; i++) {
- pages[i] = grab_cache_page(inode->i_mapping, index + i);
+ pages[i] = find_or_create_page(inode->i_mapping, index + i,
+ GFP_NOFS);
if (!pages[i]) {
faili = i - 1;
err = -ENOMEM;
* managed to copy.
*/
if (num_pages > dirty_pages) {
- if (copied > 0)
- atomic_inc(
- &BTRFS_I(inode)->outstanding_extents);
+ if (copied > 0) {
+ spin_lock(&BTRFS_I(inode)->lock);
+ BTRFS_I(inode)->outstanding_extents++;
+ spin_unlock(&BTRFS_I(inode)->lock);
+ }
btrfs_delalloc_release_space(inode,
(num_pages - dirty_pages) <<
PAGE_CACHE_SHIFT);
return inode;
spin_lock(&block_group->lock);
+ if (BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM) {
+ printk(KERN_INFO "Old style space inode found, converting.\n");
+ BTRFS_I(inode)->flags &= ~BTRFS_INODE_NODATASUM;
+ block_group->disk_cache_state = BTRFS_DC_CLEAR;
+ }
+
if (!btrfs_fs_closing(root->fs_info)) {
block_group->inode = igrab(inode);
block_group->iref = 1;
btrfs_set_inode_gid(leaf, inode_item, 0);
btrfs_set_inode_mode(leaf, inode_item, S_IFREG | 0600);
btrfs_set_inode_flags(leaf, inode_item, BTRFS_INODE_NOCOMPRESS |
- BTRFS_INODE_PREALLOC | BTRFS_INODE_NODATASUM);
+ BTRFS_INODE_PREALLOC);
btrfs_set_inode_nlink(leaf, inode_item, 1);
btrfs_set_inode_transid(leaf, inode_item, trans->transid);
btrfs_set_inode_block_group(leaf, inode_item, offset);
struct btrfs_free_space_header *header;
struct extent_buffer *leaf;
struct page *page;
- u32 *checksums = NULL, *crc;
- char *disk_crcs = NULL;
struct btrfs_key key;
struct list_head bitmaps;
u64 num_entries;
u64 num_bitmaps;
u64 generation;
- u32 cur_crc = ~(u32)0;
pgoff_t index = 0;
- unsigned long first_page_offset;
- int num_checksums;
int ret = 0;
INIT_LIST_HEAD(&bitmaps);
if (!num_entries)
goto out;
- /* Setup everything for doing checksumming */
- num_checksums = i_size_read(inode) / PAGE_CACHE_SIZE;
- checksums = crc = kzalloc(sizeof(u32) * num_checksums, GFP_NOFS);
- if (!checksums)
- goto out;
- first_page_offset = (sizeof(u32) * num_checksums) + sizeof(u64);
- disk_crcs = kzalloc(first_page_offset, GFP_NOFS);
- if (!disk_crcs)
- goto out;
-
ret = readahead_cache(inode);
if (ret)
goto out;
struct btrfs_free_space *e;
void *addr;
unsigned long offset = 0;
- unsigned long start_offset = 0;
int need_loop = 0;
if (!num_entries && !num_bitmaps)
break;
- if (index == 0) {
- start_offset = first_page_offset;
- offset = start_offset;
- }
-
- page = grab_cache_page(inode->i_mapping, index);
+ page = find_or_create_page(inode->i_mapping, index, GFP_NOFS);
if (!page)
goto free_cache;
if (index == 0) {
u64 *gen;
- memcpy(disk_crcs, addr, first_page_offset);
- gen = addr + (sizeof(u32) * num_checksums);
+ /*
+ * We put a bogus crc in the front of the first page in
+ * case old kernels try to mount a fs with the new
+ * format to make sure they discard the cache.
+ */
+ addr += sizeof(u64);
+ offset += sizeof(u64);
+
+ gen = addr;
if (*gen != BTRFS_I(inode)->generation) {
printk(KERN_ERR "btrfs: space cache generation"
" (%llu) does not match inode (%llu)\n",
page_cache_release(page);
goto free_cache;
}
- crc = (u32 *)disk_crcs;
- }
- entry = addr + start_offset;
-
- /* First lets check our crc before we do anything fun */
- cur_crc = ~(u32)0;
- cur_crc = btrfs_csum_data(root, addr + start_offset, cur_crc,
- PAGE_CACHE_SIZE - start_offset);
- btrfs_csum_final(cur_crc, (char *)&cur_crc);
- if (cur_crc != *crc) {
- printk(KERN_ERR "btrfs: crc mismatch for page %lu\n",
- index);
- kunmap(page);
- unlock_page(page);
- page_cache_release(page);
- goto free_cache;
+ addr += sizeof(u64);
+ offset += sizeof(u64);
}
- crc++;
+ entry = addr;
while (1) {
if (!num_entries)
ret = 1;
out:
- kfree(checksums);
- kfree(disk_crcs);
return ret;
free_cache:
__btrfs_remove_free_space_cache(ctl);
struct btrfs_key key;
u64 start, end, len;
u64 bytes = 0;
- u32 *crc, *checksums;
- unsigned long first_page_offset;
+ u32 crc = ~(u32)0;
int index = 0, num_pages = 0;
int entries = 0;
int bitmaps = 0;
num_pages = (i_size_read(inode) + PAGE_CACHE_SIZE - 1) >>
PAGE_CACHE_SHIFT;
- /* Since the first page has all of our checksums and our generation we
- * need to calculate the offset into the page that we can start writing
- * our entries.
- */
- first_page_offset = (sizeof(u32) * num_pages) + sizeof(u64);
-
filemap_write_and_wait(inode->i_mapping);
btrfs_wait_ordered_range(inode, inode->i_size &
~(root->sectorsize - 1), (u64)-1);
- /* make sure we don't overflow that first page */
- if (first_page_offset + sizeof(struct btrfs_free_space_entry) >= PAGE_CACHE_SIZE) {
- /* this is really the same as running out of space, where we also return 0 */
- printk(KERN_CRIT "Btrfs: free space cache was too big for the crc page\n");
- ret = 0;
- goto out_update;
- }
-
- /* We need a checksum per page. */
- crc = checksums = kzalloc(sizeof(u32) * num_pages, GFP_NOFS);
- if (!crc)
- return -1;
-
pages = kzalloc(sizeof(struct page *) * num_pages, GFP_NOFS);
- if (!pages) {
- kfree(crc);
+ if (!pages)
return -1;
- }
/* Get the cluster for this block_group if it exists */
if (block_group && !list_empty(&block_group->cluster_list))
* know and don't freak out.
*/
while (index < num_pages) {
- page = grab_cache_page(inode->i_mapping, index);
+ page = find_or_create_page(inode->i_mapping, index, GFP_NOFS);
if (!page) {
int i;
unlock_page(pages[i]);
page_cache_release(pages[i]);
}
- goto out_free;
+ goto out;
}
pages[index] = page;
index++;
/* Write out the extent entries */
do {
struct btrfs_free_space_entry *entry;
- void *addr;
+ void *addr, *orig;
unsigned long offset = 0;
- unsigned long start_offset = 0;
next_page = false;
- if (index == 0) {
- start_offset = first_page_offset;
- offset = start_offset;
- }
-
if (index >= num_pages) {
out_of_space = true;
break;
page = pages[index];
- addr = kmap(page);
- entry = addr + start_offset;
+ orig = addr = kmap(page);
+ if (index == 0) {
+ u64 *gen;
- memset(addr, 0, PAGE_CACHE_SIZE);
+ /*
+ * We're going to put in a bogus crc for this page to
+ * make sure that old kernels who aren't aware of this
+ * format will be sure to discard the cache.
+ */
+ addr += sizeof(u64);
+ offset += sizeof(u64);
+
+ gen = addr;
+ *gen = trans->transid;
+ addr += sizeof(u64);
+ offset += sizeof(u64);
+ }
+ entry = addr;
+
+ memset(addr, 0, PAGE_CACHE_SIZE - offset);
while (node && !next_page) {
struct btrfs_free_space *e;
next_page = true;
entry++;
}
- *crc = ~(u32)0;
- *crc = btrfs_csum_data(root, addr + start_offset, *crc,
- PAGE_CACHE_SIZE - start_offset);
- kunmap(page);
- btrfs_csum_final(*crc, (char *)crc);
- crc++;
+ /* Generate bogus crc value */
+ if (index == 0) {
+ u32 *tmp;
+ crc = btrfs_csum_data(root, orig + sizeof(u64), crc,
+ PAGE_CACHE_SIZE - sizeof(u64));
+ btrfs_csum_final(crc, (char *)&crc);
+ crc++;
+ tmp = orig;
+ *tmp = crc;
+ }
+
+ kunmap(page);
bytes += PAGE_CACHE_SIZE;
addr = kmap(page);
memcpy(addr, entry->bitmap, PAGE_CACHE_SIZE);
- *crc = ~(u32)0;
- *crc = btrfs_csum_data(root, addr, *crc, PAGE_CACHE_SIZE);
kunmap(page);
- btrfs_csum_final(*crc, (char *)crc);
- crc++;
bytes += PAGE_CACHE_SIZE;
list_del_init(&entry->list);
i_size_read(inode) - 1, &cached_state,
GFP_NOFS);
ret = 0;
- goto out_free;
+ goto out;
}
/* Zero out the rest of the pages just to make sure */
index++;
}
- /* Write the checksums and trans id to the first page */
- {
- void *addr;
- u64 *gen;
-
- page = pages[0];
-
- addr = kmap(page);
- memcpy(addr, checksums, sizeof(u32) * num_pages);
- gen = addr + (sizeof(u32) * num_pages);
- *gen = trans->transid;
- kunmap(page);
- }
-
ret = btrfs_dirty_pages(root, inode, pages, num_pages, 0,
bytes, &cached_state);
btrfs_drop_pages(pages, num_pages);
if (ret) {
ret = 0;
- goto out_free;
+ goto out;
}
BTRFS_I(inode)->generation = trans->transid;
clear_extent_bit(&BTRFS_I(inode)->io_tree, 0, bytes - 1,
EXTENT_DIRTY | EXTENT_DELALLOC |
EXTENT_DO_ACCOUNTING, 0, 0, NULL, GFP_NOFS);
- goto out_free;
+ goto out;
}
leaf = path->nodes[0];
if (ret > 0) {
EXTENT_DO_ACCOUNTING, 0, 0, NULL,
GFP_NOFS);
btrfs_release_path(path);
- goto out_free;
+ goto out;
}
}
header = btrfs_item_ptr(leaf, path->slots[0],
ret = 1;
-out_free:
- kfree(checksums);
+out:
kfree(pages);
-
-out_update:
if (ret != 1) {
invalidate_inode_pages2_range(inode->i_mapping, 0, index);
BTRFS_I(inode)->generation = 0;
return alloc_hint;
}
-static inline bool is_free_space_inode(struct btrfs_root *root,
- struct inode *inode)
-{
- if (root == root->fs_info->tree_root ||
- BTRFS_I(inode)->location.objectid == BTRFS_FREE_INO_OBJECTID)
- return true;
- return false;
-}
-
/*
* when extent_io.c finds a delayed allocation range in the file,
* the call backs end up in this code. The basic idea is to
struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
int ret = 0;
- BUG_ON(is_free_space_inode(root, inode));
+ BUG_ON(btrfs_is_free_space_inode(root, inode));
trans = btrfs_join_transaction(root);
BUG_ON(IS_ERR(trans));
trans->block_rsv = &root->fs_info->delalloc_block_rsv;
path = btrfs_alloc_path();
BUG_ON(!path);
- nolock = is_free_space_inode(root, inode);
+ nolock = btrfs_is_free_space_inode(root, inode);
if (nolock)
trans = btrfs_join_transaction_nolock(root);
if (!(orig->state & EXTENT_DELALLOC))
return 0;
- atomic_inc(&BTRFS_I(inode)->outstanding_extents);
+ spin_lock(&BTRFS_I(inode)->lock);
+ BTRFS_I(inode)->outstanding_extents++;
+ spin_unlock(&BTRFS_I(inode)->lock);
return 0;
}
if (!(other->state & EXTENT_DELALLOC))
return 0;
- atomic_dec(&BTRFS_I(inode)->outstanding_extents);
+ spin_lock(&BTRFS_I(inode)->lock);
+ BTRFS_I(inode)->outstanding_extents--;
+ spin_unlock(&BTRFS_I(inode)->lock);
return 0;
}
if (!(state->state & EXTENT_DELALLOC) && (*bits & EXTENT_DELALLOC)) {
struct btrfs_root *root = BTRFS_I(inode)->root;
u64 len = state->end + 1 - state->start;
- bool do_list = !is_free_space_inode(root, inode);
+ bool do_list = !btrfs_is_free_space_inode(root, inode);
- if (*bits & EXTENT_FIRST_DELALLOC)
+ if (*bits & EXTENT_FIRST_DELALLOC) {
*bits &= ~EXTENT_FIRST_DELALLOC;
- else
- atomic_inc(&BTRFS_I(inode)->outstanding_extents);
+ } else {
+ spin_lock(&BTRFS_I(inode)->lock);
+ BTRFS_I(inode)->outstanding_extents++;
+ spin_unlock(&BTRFS_I(inode)->lock);
+ }
spin_lock(&root->fs_info->delalloc_lock);
BTRFS_I(inode)->delalloc_bytes += len;
if ((state->state & EXTENT_DELALLOC) && (*bits & EXTENT_DELALLOC)) {
struct btrfs_root *root = BTRFS_I(inode)->root;
u64 len = state->end + 1 - state->start;
- bool do_list = !is_free_space_inode(root, inode);
+ bool do_list = !btrfs_is_free_space_inode(root, inode);
- if (*bits & EXTENT_FIRST_DELALLOC)
+ if (*bits & EXTENT_FIRST_DELALLOC) {
*bits &= ~EXTENT_FIRST_DELALLOC;
- else if (!(*bits & EXTENT_DO_ACCOUNTING))
- atomic_dec(&BTRFS_I(inode)->outstanding_extents);
+ } else if (!(*bits & EXTENT_DO_ACCOUNTING)) {
+ spin_lock(&BTRFS_I(inode)->lock);
+ BTRFS_I(inode)->outstanding_extents--;
+ spin_unlock(&BTRFS_I(inode)->lock);
+ }
if (*bits & EXTENT_DO_ACCOUNTING)
btrfs_delalloc_release_metadata(inode, len);
skip_sum = BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM;
- if (is_free_space_inode(root, inode))
+ if (btrfs_is_free_space_inode(root, inode))
ret = btrfs_bio_wq_end_io(root->fs_info, bio, 2);
else
ret = btrfs_bio_wq_end_io(root->fs_info, bio, 0);
return 0;
BUG_ON(!ordered_extent);
- nolock = is_free_space_inode(root, inode);
+ nolock = btrfs_is_free_space_inode(root, inode);
if (test_bit(BTRFS_ORDERED_NOCOW, &ordered_extent->flags)) {
BUG_ON(!list_empty(&ordered_extent->list));
inode_item = btrfs_item_ptr(leaf, path->slots[0],
struct btrfs_inode_item);
- if (!leaf->map_token)
- map_private_extent_buffer(leaf, (unsigned long)inode_item,
- sizeof(struct btrfs_inode_item),
- &leaf->map_token, &leaf->kaddr,
- &leaf->map_start, &leaf->map_len,
- KM_USER1);
-
inode->i_mode = btrfs_inode_mode(leaf, inode_item);
inode->i_nlink = btrfs_inode_nlink(leaf, inode_item);
inode->i_uid = btrfs_inode_uid(leaf, inode_item);
if (!maybe_acls)
cache_no_acl(inode);
- if (leaf->map_token) {
- unmap_extent_buffer(leaf, leaf->map_token, KM_USER1);
- leaf->map_token = NULL;
- }
-
btrfs_free_path(path);
switch (inode->i_mode & S_IFMT) {
struct btrfs_inode_item *item,
struct inode *inode)
{
- if (!leaf->map_token)
- map_private_extent_buffer(leaf, (unsigned long)item,
- sizeof(struct btrfs_inode_item),
- &leaf->map_token, &leaf->kaddr,
- &leaf->map_start, &leaf->map_len,
- KM_USER1);
-
btrfs_set_inode_uid(leaf, item, inode->i_uid);
btrfs_set_inode_gid(leaf, item, inode->i_gid);
btrfs_set_inode_size(leaf, item, BTRFS_I(inode)->disk_i_size);
btrfs_set_inode_rdev(leaf, item, inode->i_rdev);
btrfs_set_inode_flags(leaf, item, BTRFS_I(inode)->flags);
btrfs_set_inode_block_group(leaf, item, 0);
-
- if (leaf->map_token) {
- unmap_extent_buffer(leaf, leaf->map_token, KM_USER1);
- leaf->map_token = NULL;
- }
}
/*
* The data relocation inode should also be directly updated
* without delay
*/
- if (!is_free_space_inode(root, inode)
+ if (!btrfs_is_free_space_inode(root, inode)
&& root->root_key.objectid != BTRFS_DATA_RELOC_TREE_OBJECTID) {
ret = btrfs_delayed_update_inode(trans, root, inode);
if (!ret)
ret = -ENOMEM;
again:
- page = grab_cache_page(mapping, index);
+ page = find_or_create_page(mapping, index, GFP_NOFS);
if (!page) {
btrfs_delalloc_release_space(inode, PAGE_CACHE_SIZE);
goto out;
truncate_inode_pages(&inode->i_data, 0);
if (inode->i_nlink && (btrfs_root_refs(&root->root_item) != 0 ||
- is_free_space_inode(root, inode)))
+ btrfs_is_free_space_inode(root, inode)))
goto no_delete;
if (is_bad_inode(inode)) {
if (BTRFS_I(inode)->dummy_inode)
return 0;
- if (btrfs_fs_closing(root->fs_info) && is_free_space_inode(root, inode))
+ if (btrfs_fs_closing(root->fs_info) && btrfs_is_free_space_inode(root, inode))
nolock = true;
if (wbc->sync_mode == WB_SYNC_ALL) {
ei->index_cnt = (u64)-1;
ei->last_unlink_trans = 0;
- atomic_set(&ei->outstanding_extents, 0);
- atomic_set(&ei->reserved_extents, 0);
+ spin_lock_init(&ei->lock);
+ ei->outstanding_extents = 0;
+ ei->reserved_extents = 0;
ei->ordered_data_close = 0;
ei->orphan_meta_reserved = 0;
WARN_ON(!list_empty(&inode->i_dentry));
WARN_ON(inode->i_data.nrpages);
- WARN_ON(atomic_read(&BTRFS_I(inode)->outstanding_extents));
- WARN_ON(atomic_read(&BTRFS_I(inode)->reserved_extents));
+ WARN_ON(BTRFS_I(inode)->outstanding_extents);
+ WARN_ON(BTRFS_I(inode)->reserved_extents);
/*
* This can happen where we create an inode, but somebody else also
struct btrfs_root *root = BTRFS_I(inode)->root;
if (btrfs_root_refs(&root->root_item) == 0 &&
- !is_free_space_inode(root, inode))
+ !btrfs_is_free_space_inode(root, inode))
return 1;
else
return generic_drop_inode(inode);
/* step one, lock all the pages */
for (i = 0; i < num_pages; i++) {
struct page *page;
- page = grab_cache_page(inode->i_mapping,
- start_index + i);
+ page = find_or_create_page(inode->i_mapping,
+ start_index + i, GFP_NOFS);
if (!page)
break;
GFP_NOFS);
if (i_done != num_pages) {
- atomic_inc(&BTRFS_I(inode)->outstanding_extents);
+ spin_lock(&BTRFS_I(inode)->lock);
+ BTRFS_I(inode)->outstanding_extents++;
+ spin_unlock(&BTRFS_I(inode)->lock);
btrfs_delalloc_release_space(inode,
(num_pages - i_done) << PAGE_CACHE_SHIFT);
}
#include "extent_io.h"
#include "locking.h"
-static inline void spin_nested(struct extent_buffer *eb)
-{
- spin_lock(&eb->lock);
-}
+void btrfs_assert_tree_read_locked(struct extent_buffer *eb);
/*
- * Setting a lock to blocking will drop the spinlock and set the
- * flag that forces other procs who want the lock to wait. After
- * this you can safely schedule with the lock held.
+ * if we currently have a spinning reader or writer lock
+ * (indicated by the rw flag) this will bump the count
+ * of blocking holders and drop the spinlock.
*/
-void btrfs_set_lock_blocking(struct extent_buffer *eb)
+void btrfs_set_lock_blocking_rw(struct extent_buffer *eb, int rw)
{
- if (!test_bit(EXTENT_BUFFER_BLOCKING, &eb->bflags)) {
- set_bit(EXTENT_BUFFER_BLOCKING, &eb->bflags);
- spin_unlock(&eb->lock);
+ if (rw == BTRFS_WRITE_LOCK) {
+ if (atomic_read(&eb->blocking_writers) == 0) {
+ WARN_ON(atomic_read(&eb->spinning_writers) != 1);
+ atomic_dec(&eb->spinning_writers);
+ btrfs_assert_tree_locked(eb);
+ atomic_inc(&eb->blocking_writers);
+ write_unlock(&eb->lock);
+ }
+ } else if (rw == BTRFS_READ_LOCK) {
+ btrfs_assert_tree_read_locked(eb);
+ atomic_inc(&eb->blocking_readers);
+ WARN_ON(atomic_read(&eb->spinning_readers) == 0);
+ atomic_dec(&eb->spinning_readers);
+ read_unlock(&eb->lock);
}
- /* exit with the spin lock released and the bit set */
+ return;
}
/*
- * clearing the blocking flag will take the spinlock again.
- * After this you can't safely schedule
+ * if we currently have a blocking lock, take the spinlock
+ * and drop our blocking count
*/
-void btrfs_clear_lock_blocking(struct extent_buffer *eb)
+void btrfs_clear_lock_blocking_rw(struct extent_buffer *eb, int rw)
{
- if (test_bit(EXTENT_BUFFER_BLOCKING, &eb->bflags)) {
- spin_nested(eb);
- clear_bit(EXTENT_BUFFER_BLOCKING, &eb->bflags);
- smp_mb__after_clear_bit();
+ if (rw == BTRFS_WRITE_LOCK_BLOCKING) {
+ BUG_ON(atomic_read(&eb->blocking_writers) != 1);
+ write_lock(&eb->lock);
+ WARN_ON(atomic_read(&eb->spinning_writers));
+ atomic_inc(&eb->spinning_writers);
+ if (atomic_dec_and_test(&eb->blocking_writers))
+ wake_up(&eb->write_lock_wq);
+ } else if (rw == BTRFS_READ_LOCK_BLOCKING) {
+ BUG_ON(atomic_read(&eb->blocking_readers) == 0);
+ read_lock(&eb->lock);
+ atomic_inc(&eb->spinning_readers);
+ if (atomic_dec_and_test(&eb->blocking_readers))
+ wake_up(&eb->read_lock_wq);
}
- /* exit with the spin lock held */
+ return;
}
/*
- * unfortunately, many of the places that currently set a lock to blocking
- * don't end up blocking for very long, and often they don't block
- * at all. For a dbench 50 run, if we don't spin on the blocking bit
- * at all, the context switch rate can jump up to 400,000/sec or more.
- *
- * So, we're still stuck with this crummy spin on the blocking bit,
- * at least until the most common causes of the short blocks
- * can be dealt with.
+ * take a spinning read lock. This will wait for any blocking
+ * writers
*/
-static int btrfs_spin_on_block(struct extent_buffer *eb)
+void btrfs_tree_read_lock(struct extent_buffer *eb)
{
- int i;
-
- for (i = 0; i < 512; i++) {
- if (!test_bit(EXTENT_BUFFER_BLOCKING, &eb->bflags))
- return 1;
- if (need_resched())
- break;
- cpu_relax();
+again:
+ wait_event(eb->write_lock_wq, atomic_read(&eb->blocking_writers) == 0);
+ read_lock(&eb->lock);
+ if (atomic_read(&eb->blocking_writers)) {
+ read_unlock(&eb->lock);
+ wait_event(eb->write_lock_wq,
+ atomic_read(&eb->blocking_writers) == 0);
+ goto again;
}
- return 0;
+ atomic_inc(&eb->read_locks);
+ atomic_inc(&eb->spinning_readers);
}
/*
- * This is somewhat different from trylock. It will take the
- * spinlock but if it finds the lock is set to blocking, it will
- * return without the lock held.
- *
- * returns 1 if it was able to take the lock and zero otherwise
- *
- * After this call, scheduling is not safe without first calling
- * btrfs_set_lock_blocking()
+ * returns 1 if we get the read lock and 0 if we don't
+ * this won't wait for blocking writers
*/
-int btrfs_try_spin_lock(struct extent_buffer *eb)
+int btrfs_try_tree_read_lock(struct extent_buffer *eb)
{
- int i;
+ if (atomic_read(&eb->blocking_writers))
+ return 0;
- if (btrfs_spin_on_block(eb)) {
- spin_nested(eb);
- if (!test_bit(EXTENT_BUFFER_BLOCKING, &eb->bflags))
- return 1;
- spin_unlock(&eb->lock);
+ read_lock(&eb->lock);
+ if (atomic_read(&eb->blocking_writers)) {
+ read_unlock(&eb->lock);
+ return 0;
}
- /* spin for a bit on the BLOCKING flag */
- for (i = 0; i < 2; i++) {
- cpu_relax();
- if (!btrfs_spin_on_block(eb))
- break;
-
- spin_nested(eb);
- if (!test_bit(EXTENT_BUFFER_BLOCKING, &eb->bflags))
- return 1;
- spin_unlock(&eb->lock);
- }
- return 0;
+ atomic_inc(&eb->read_locks);
+ atomic_inc(&eb->spinning_readers);
+ return 1;
}
/*
- * the autoremove wake function will return 0 if it tried to wake up
- * a process that was already awake, which means that process won't
- * count as an exclusive wakeup. The waitq code will continue waking
- * procs until it finds one that was actually sleeping.
- *
- * For btrfs, this isn't quite what we want. We want a single proc
- * to be notified that the lock is ready for taking. If that proc
- * already happen to be awake, great, it will loop around and try for
- * the lock.
- *
- * So, btrfs_wake_function always returns 1, even when the proc that we
- * tried to wake up was already awake.
+ * returns 1 if we get the read lock and 0 if we don't
+ * this won't wait for blocking writers or readers
*/
-static int btrfs_wake_function(wait_queue_t *wait, unsigned mode,
- int sync, void *key)
+int btrfs_try_tree_write_lock(struct extent_buffer *eb)
{
- autoremove_wake_function(wait, mode, sync, key);
+ if (atomic_read(&eb->blocking_writers) ||
+ atomic_read(&eb->blocking_readers))
+ return 0;
+ write_lock(&eb->lock);
+ if (atomic_read(&eb->blocking_writers) ||
+ atomic_read(&eb->blocking_readers)) {
+ write_unlock(&eb->lock);
+ return 0;
+ }
+ atomic_inc(&eb->write_locks);
+ atomic_inc(&eb->spinning_writers);
return 1;
}
/*
- * returns with the extent buffer spinlocked.
- *
- * This will spin and/or wait as required to take the lock, and then
- * return with the spinlock held.
- *
- * After this call, scheduling is not safe without first calling
- * btrfs_set_lock_blocking()
+ * drop a spinning read lock
+ */
+void btrfs_tree_read_unlock(struct extent_buffer *eb)
+{
+ btrfs_assert_tree_read_locked(eb);
+ WARN_ON(atomic_read(&eb->spinning_readers) == 0);
+ atomic_dec(&eb->spinning_readers);
+ atomic_dec(&eb->read_locks);
+ read_unlock(&eb->lock);
+}
+
+/*
+ * drop a blocking read lock
+ */
+void btrfs_tree_read_unlock_blocking(struct extent_buffer *eb)
+{
+ btrfs_assert_tree_read_locked(eb);
+ WARN_ON(atomic_read(&eb->blocking_readers) == 0);
+ if (atomic_dec_and_test(&eb->blocking_readers))
+ wake_up(&eb->read_lock_wq);
+ atomic_dec(&eb->read_locks);
+}
+
+/*
+ * take a spinning write lock. This will wait for both
+ * blocking readers or writers
*/
int btrfs_tree_lock(struct extent_buffer *eb)
{
- DEFINE_WAIT(wait);
- wait.func = btrfs_wake_function;
-
- if (!btrfs_spin_on_block(eb))
- goto sleep;
-
- while(1) {
- spin_nested(eb);
-
- /* nobody is blocking, exit with the spinlock held */
- if (!test_bit(EXTENT_BUFFER_BLOCKING, &eb->bflags))
- return 0;
-
- /*
- * we have the spinlock, but the real owner is blocking.
- * wait for them
- */
- spin_unlock(&eb->lock);
-
- /*
- * spin for a bit, and if the blocking flag goes away,
- * loop around
- */
- cpu_relax();
- if (btrfs_spin_on_block(eb))
- continue;
-sleep:
- prepare_to_wait_exclusive(&eb->lock_wq, &wait,
- TASK_UNINTERRUPTIBLE);
-
- if (test_bit(EXTENT_BUFFER_BLOCKING, &eb->bflags))
- schedule();
-
- finish_wait(&eb->lock_wq, &wait);
+again:
+ wait_event(eb->read_lock_wq, atomic_read(&eb->blocking_readers) == 0);
+ wait_event(eb->write_lock_wq, atomic_read(&eb->blocking_writers) == 0);
+ write_lock(&eb->lock);
+ if (atomic_read(&eb->blocking_readers)) {
+ write_unlock(&eb->lock);
+ wait_event(eb->read_lock_wq,
+ atomic_read(&eb->blocking_readers) == 0);
+ goto again;
}
+ if (atomic_read(&eb->blocking_writers)) {
+ write_unlock(&eb->lock);
+ wait_event(eb->write_lock_wq,
+ atomic_read(&eb->blocking_writers) == 0);
+ goto again;
+ }
+ WARN_ON(atomic_read(&eb->spinning_writers));
+ atomic_inc(&eb->spinning_writers);
+ atomic_inc(&eb->write_locks);
return 0;
}
+/*
+ * drop a spinning or a blocking write lock.
+ */
int btrfs_tree_unlock(struct extent_buffer *eb)
{
- /*
- * if we were a blocking owner, we don't have the spinlock held
- * just clear the bit and look for waiters
- */
- if (test_and_clear_bit(EXTENT_BUFFER_BLOCKING, &eb->bflags))
- smp_mb__after_clear_bit();
- else
- spin_unlock(&eb->lock);
-
- if (waitqueue_active(&eb->lock_wq))
- wake_up(&eb->lock_wq);
+ int blockers = atomic_read(&eb->blocking_writers);
+
+ BUG_ON(blockers > 1);
+
+ btrfs_assert_tree_locked(eb);
+ atomic_dec(&eb->write_locks);
+
+ if (blockers) {
+ WARN_ON(atomic_read(&eb->spinning_writers));
+ atomic_dec(&eb->blocking_writers);
+ smp_wmb();
+ wake_up(&eb->write_lock_wq);
+ } else {
+ WARN_ON(atomic_read(&eb->spinning_writers) != 1);
+ atomic_dec(&eb->spinning_writers);
+ write_unlock(&eb->lock);
+ }
return 0;
}
void btrfs_assert_tree_locked(struct extent_buffer *eb)
{
- if (!test_bit(EXTENT_BUFFER_BLOCKING, &eb->bflags))
- assert_spin_locked(&eb->lock);
+ BUG_ON(!atomic_read(&eb->write_locks));
+}
+
+void btrfs_assert_tree_read_locked(struct extent_buffer *eb)
+{
+ BUG_ON(!atomic_read(&eb->read_locks));
}
#ifndef __BTRFS_LOCKING_
#define __BTRFS_LOCKING_
+#define BTRFS_WRITE_LOCK 1
+#define BTRFS_READ_LOCK 2
+#define BTRFS_WRITE_LOCK_BLOCKING 3
+#define BTRFS_READ_LOCK_BLOCKING 4
+
int btrfs_tree_lock(struct extent_buffer *eb);
int btrfs_tree_unlock(struct extent_buffer *eb);
int btrfs_try_spin_lock(struct extent_buffer *eb);
-void btrfs_set_lock_blocking(struct extent_buffer *eb);
-void btrfs_clear_lock_blocking(struct extent_buffer *eb);
+void btrfs_tree_read_lock(struct extent_buffer *eb);
+void btrfs_tree_read_unlock(struct extent_buffer *eb);
+void btrfs_tree_read_unlock_blocking(struct extent_buffer *eb);
+void btrfs_set_lock_blocking_rw(struct extent_buffer *eb, int rw);
+void btrfs_clear_lock_blocking_rw(struct extent_buffer *eb, int rw);
void btrfs_assert_tree_locked(struct extent_buffer *eb);
+int btrfs_try_tree_read_lock(struct extent_buffer *eb);
+int btrfs_try_tree_write_lock(struct extent_buffer *eb);
+
+static inline void btrfs_tree_unlock_rw(struct extent_buffer *eb, int rw)
+{
+ if (rw == BTRFS_WRITE_LOCK || rw == BTRFS_WRITE_LOCK_BLOCKING)
+ btrfs_tree_unlock(eb);
+ else if (rw == BTRFS_READ_LOCK_BLOCKING)
+ btrfs_tree_read_unlock_blocking(eb);
+ else if (rw == BTRFS_READ_LOCK)
+ btrfs_tree_read_unlock(eb);
+ else
+ BUG();
+}
+
+static inline void btrfs_set_lock_blocking(struct extent_buffer *eb)
+{
+ btrfs_set_lock_blocking_rw(eb, BTRFS_WRITE_LOCK);
+}
+
+static inline void btrfs_clear_lock_blocking(struct extent_buffer *eb)
+{
+ btrfs_clear_lock_blocking_rw(eb, BTRFS_WRITE_LOCK_BLOCKING);
+}
#endif
page_cache_sync_readahead(inode->i_mapping,
ra, NULL, index,
last_index + 1 - index);
- page = grab_cache_page(inode->i_mapping, index);
+ page = find_or_create_page(inode->i_mapping, index,
+ GFP_NOFS);
if (!page) {
btrfs_delalloc_release_metadata(inode,
PAGE_CACHE_SIZE);
unsigned long part_offset = (unsigned long)s; \
unsigned long offset = part_offset + offsetof(type, member); \
type *p; \
- /* ugly, but we want the fast path here */ \
- if (eb->map_token && offset >= eb->map_start && \
- offset + sizeof(((type *)0)->member) <= eb->map_start + \
- eb->map_len) { \
- p = (type *)(eb->kaddr + part_offset - eb->map_start); \
- return le##bits##_to_cpu(p->member); \
- } \
- { \
- int err; \
- char *map_token; \
- char *kaddr; \
- int unmap_on_exit = (eb->map_token == NULL); \
- unsigned long map_start; \
- unsigned long map_len; \
- u##bits res; \
- err = map_extent_buffer(eb, offset, \
- sizeof(((type *)0)->member), \
- &map_token, &kaddr, \
- &map_start, &map_len, KM_USER1); \
- if (err) { \
- __le##bits leres; \
- read_eb_member(eb, s, type, member, &leres); \
- return le##bits##_to_cpu(leres); \
- } \
- p = (type *)(kaddr + part_offset - map_start); \
- res = le##bits##_to_cpu(p->member); \
- if (unmap_on_exit) \
- unmap_extent_buffer(eb, map_token, KM_USER1); \
- return res; \
- } \
+ int err; \
+ char *kaddr; \
+ unsigned long map_start; \
+ unsigned long map_len; \
+ u##bits res; \
+ err = map_private_extent_buffer(eb, offset, \
+ sizeof(((type *)0)->member), \
+ &kaddr, &map_start, &map_len); \
+ if (err) { \
+ __le##bits leres; \
+ read_eb_member(eb, s, type, member, &leres); \
+ return le##bits##_to_cpu(leres); \
+ } \
+ p = (type *)(kaddr + part_offset - map_start); \
+ res = le##bits##_to_cpu(p->member); \
+ return res; \
} \
void btrfs_set_##name(struct extent_buffer *eb, \
type *s, u##bits val) \
unsigned long part_offset = (unsigned long)s; \
unsigned long offset = part_offset + offsetof(type, member); \
type *p; \
- /* ugly, but we want the fast path here */ \
- if (eb->map_token && offset >= eb->map_start && \
- offset + sizeof(((type *)0)->member) <= eb->map_start + \
- eb->map_len) { \
- p = (type *)(eb->kaddr + part_offset - eb->map_start); \
- p->member = cpu_to_le##bits(val); \
- return; \
- } \
- { \
- int err; \
- char *map_token; \
- char *kaddr; \
- int unmap_on_exit = (eb->map_token == NULL); \
- unsigned long map_start; \
- unsigned long map_len; \
- err = map_extent_buffer(eb, offset, \
- sizeof(((type *)0)->member), \
- &map_token, &kaddr, \
- &map_start, &map_len, KM_USER1); \
- if (err) { \
- __le##bits val2; \
- val2 = cpu_to_le##bits(val); \
- write_eb_member(eb, s, type, member, &val2); \
- return; \
- } \
- p = (type *)(kaddr + part_offset - map_start); \
- p->member = cpu_to_le##bits(val); \
- if (unmap_on_exit) \
- unmap_extent_buffer(eb, map_token, KM_USER1); \
- } \
+ int err; \
+ char *kaddr; \
+ unsigned long map_start; \
+ unsigned long map_len; \
+ err = map_private_extent_buffer(eb, offset, \
+ sizeof(((type *)0)->member), \
+ &kaddr, &map_start, &map_len); \
+ if (err) { \
+ __le##bits val2; \
+ val2 = cpu_to_le##bits(val); \
+ write_eb_member(eb, s, type, member, &val2); \
+ return; \
+ } \
+ p = (type *)(kaddr + part_offset - map_start); \
+ p->member = cpu_to_le##bits(val); \
}
#include "ctree.h"
struct btrfs_disk_key *disk_key, int nr)
{
unsigned long ptr = btrfs_node_key_ptr_offset(nr);
- if (eb->map_token && ptr >= eb->map_start &&
- ptr + sizeof(*disk_key) <= eb->map_start + eb->map_len) {
- memcpy(disk_key, eb->kaddr + ptr - eb->map_start,
- sizeof(*disk_key));
- return;
- } else if (eb->map_token) {
- unmap_extent_buffer(eb, eb->map_token, KM_USER1);
- eb->map_token = NULL;
- }
read_eb_member(eb, (struct btrfs_key_ptr *)ptr,
struct btrfs_key_ptr, key, disk_key);
}
{
struct btrfs_trans_handle *h;
struct btrfs_transaction *cur_trans;
- int retries = 0;
+ u64 num_bytes = 0;
int ret;
if (root->fs_info->fs_state & BTRFS_SUPER_FLAG_ERROR)
h->block_rsv = NULL;
goto got_it;
}
+
+ /*
+ * Do the reservation before we join the transaction so we can do all
+ * the appropriate flushing if need be.
+ */
+ if (num_items > 0 && root != root->fs_info->chunk_root) {
+ num_bytes = btrfs_calc_trans_metadata_size(root, num_items);
+ ret = btrfs_block_rsv_add(NULL, root,
+ &root->fs_info->trans_block_rsv,
+ num_bytes);
+ if (ret)
+ return ERR_PTR(ret);
+ }
again:
h = kmem_cache_alloc(btrfs_trans_handle_cachep, GFP_NOFS);
if (!h)
goto again;
}
- if (num_items > 0) {
- ret = btrfs_trans_reserve_metadata(h, root, num_items);
- if (ret == -EAGAIN && !retries) {
- retries++;
- btrfs_commit_transaction(h, root);
- goto again;
- } else if (ret == -EAGAIN) {
- /*
- * We have already retried and got EAGAIN, so really we
- * don't have space, so set ret to -ENOSPC.
- */
- ret = -ENOSPC;
- }
-
- if (ret < 0) {
- btrfs_end_transaction(h, root);
- return ERR_PTR(ret);
- }
+ if (num_bytes) {
+ h->block_rsv = &root->fs_info->trans_block_rsv;
+ h->bytes_reserved = num_bytes;
}
got_it:
}
if (lock && cur_trans->blocked && !cur_trans->in_commit) {
- if (throttle)
+ if (throttle) {
+ /*
+ * We may race with somebody else here so end up having
+ * to call end_transaction on ourselves again, so inc
+ * our use_count.
+ */
+ trans->use_count++;
return btrfs_commit_transaction(trans, root);
- else
+ } else {
wake_up_process(info->transaction_kthread);
+ }
}
WARN_ON(cur_trans != info->running_transaction);
btrfs_read_buffer(next, ptr_gen);
btrfs_tree_lock(next);
- clean_tree_block(trans, root, next);
btrfs_set_lock_blocking(next);
+ clean_tree_block(trans, root, next);
btrfs_wait_tree_block_writeback(next);
btrfs_tree_unlock(next);
next = path->nodes[*level];
btrfs_tree_lock(next);
- clean_tree_block(trans, root, next);
btrfs_set_lock_blocking(next);
+ clean_tree_block(trans, root, next);
btrfs_wait_tree_block_writeback(next);
btrfs_tree_unlock(next);
next = path->nodes[orig_level];
btrfs_tree_lock(next);
- clean_tree_block(trans, log, next);
btrfs_set_lock_blocking(next);
+ clean_tree_block(trans, log, next);
btrfs_wait_tree_block_writeback(next);
btrfs_tree_unlock(next);
if (!sb)
return -ENOMEM;
btrfs_set_buffer_uptodate(sb);
- btrfs_set_buffer_lockdep_class(sb, 0);
+ btrfs_set_buffer_lockdep_class(root->root_key.objectid, sb, 0);
write_extent_buffer(sb, super_copy, 0, BTRFS_SUPER_INFO_SIZE);
array_size = btrfs_super_sys_array_size(super_copy);
if (!path)
return -ENOMEM;
- /* first lets see if we already have this xattr */
- di = btrfs_lookup_xattr(trans, root, path, btrfs_ino(inode), name,
- strlen(name), -1);
- if (IS_ERR(di)) {
- ret = PTR_ERR(di);
- goto out;
- }
-
- /* ok we already have this xattr, lets remove it */
- if (di) {
- /* if we want create only exit */
- if (flags & XATTR_CREATE) {
- ret = -EEXIST;
+ if (flags & XATTR_REPLACE) {
+ di = btrfs_lookup_xattr(trans, root, path, btrfs_ino(inode), name,
+ name_len, -1);
+ if (IS_ERR(di)) {
+ ret = PTR_ERR(di);
+ goto out;
+ } else if (!di) {
+ ret = -ENODATA;
goto out;
}
-
ret = btrfs_delete_one_dir_name(trans, root, path, di);
- BUG_ON(ret);
+ if (ret)
+ goto out;
btrfs_release_path(path);
+ }
- /* if we don't have a value then we are removing the xattr */
- if (!value)
+again:
+ ret = btrfs_insert_xattr_item(trans, root, path, btrfs_ino(inode),
+ name, name_len, value, size);
+ if (ret == -EEXIST) {
+ if (flags & XATTR_CREATE)
goto out;
- } else {
+ /*
+ * We can't use the path we already have since we won't have the
+ * proper locking for a delete, so release the path and
+ * re-lookup to delete the thing.
+ */
btrfs_release_path(path);
+ di = btrfs_lookup_xattr(trans, root, path, btrfs_ino(inode),
+ name, name_len, -1);
+ if (IS_ERR(di)) {
+ ret = PTR_ERR(di);
+ goto out;
+ } else if (!di) {
+ /* Shouldn't happen but just in case... */
+ btrfs_release_path(path);
+ goto again;
+ }
- if (flags & XATTR_REPLACE) {
- /* we couldn't find the attr to replace */
- ret = -ENODATA;
+ ret = btrfs_delete_one_dir_name(trans, root, path, di);
+ if (ret)
goto out;
+
+ /*
+ * We have a value to set, so go back and try to insert it now.
+ */
+ if (value) {
+ btrfs_release_path(path);
+ goto again;
}
}
-
- /* ok we have to create a completely new xattr */
- ret = btrfs_insert_xattr_item(trans, root, path, btrfs_ino(inode),
- name, name_len, value, size);
- BUG_ON(ret);
out:
btrfs_free_path(path);
return ret;
projects / firefly-linux-kernel-4.4.55.git / commitdiff