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Btrfs: Fix disk_i_size update corner case

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There are some cases file extents are inserted without involving
ordered struct. In these cases, we update disk_i_size directly,
without checking pending ordered extent and DELALLOC bit. This
patch extends btrfs_ordered_update_i_size() to handle these cases.

Signed-off-by: Yan Zheng <zheng.yan@oracle.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
This commit is contained in:
Yan, Zheng 2009-11-12 09:34:21 +00:00 committed by Chris Mason
parent 920bbbfb05
commit c216775458
4 changed files with 127 additions and 56 deletions
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5
fs/btrfs/btrfs_inode.h
View File

@ -44,9 +44,6 @@ struct btrfs_inode {
*/
struct extent_io_tree io_failure_tree;
/* held while inesrting or deleting extents from files */
struct mutex extent_mutex;
/* held while logging the inode in tree-log.c */
struct mutex log_mutex;
@ -166,7 +163,7 @@ static inline struct btrfs_inode *BTRFS_I(struct inode *inode)
static inline void btrfs_i_size_write(struct inode *inode, u64 size)
{
inode->i_size = size;
i_size_write(inode, size);
BTRFS_I(inode)->disk_i_size = size;
}

71
fs/btrfs/inode.c
View File

@ -188,8 +188,18 @@ static noinline int insert_inline_extent(struct btrfs_trans_handle *trans,
btrfs_mark_buffer_dirty(leaf);
btrfs_free_path(path);
/*
* we're an inline extent, so nobody can
* extend the file past i_size without locking
* a page we already have locked.
*
* We must do any isize and inode updates
* before we unlock the pages. Otherwise we
* could end up racing with unlink.
*/
BTRFS_I(inode)->disk_i_size = inode->i_size;
btrfs_update_inode(trans, root, inode);
return 0;
fail:
btrfs_free_path(path);
@ -415,7 +425,6 @@ again:
start, end,
total_compressed, pages);
}
btrfs_end_transaction(trans, root);
if (ret == 0) {
/*
* inline extent creation worked, we don't need
@ -429,9 +438,11 @@ again:
EXTENT_CLEAR_DELALLOC |
EXTENT_CLEAR_ACCOUNTING |
EXTENT_SET_WRITEBACK | EXTENT_END_WRITEBACK);
ret = 0;
btrfs_end_transaction(trans, root);
goto free_pages_out;
}
btrfs_end_transaction(trans, root);
}
if (will_compress) {
@ -542,7 +553,6 @@ static noinline int submit_compressed_extents(struct inode *inode,
if (list_empty(&async_cow->extents))
return 0;
trans = btrfs_join_transaction(root, 1);
while (!list_empty(&async_cow->extents)) {
async_extent = list_entry(async_cow->extents.next,
@ -589,19 +599,15 @@ retry:
lock_extent(io_tree, async_extent->start,
async_extent->start + async_extent->ram_size - 1,
GFP_NOFS);
/*
* here we're doing allocation and writeback of the
* compressed pages
*/
btrfs_drop_extent_cache(inode, async_extent->start,
async_extent->start +
async_extent->ram_size - 1, 0);
trans = btrfs_join_transaction(root, 1);
ret = btrfs_reserve_extent(trans, root,
async_extent->compressed_size,
async_extent->compressed_size,
0, alloc_hint,
(u64)-1, &ins, 1);
btrfs_end_transaction(trans, root);
if (ret) {
int i;
for (i = 0; i < async_extent->nr_pages; i++) {
@ -617,6 +623,14 @@ retry:
goto retry;
}
/*
* here we're doing allocation and writeback of the
* compressed pages
*/
btrfs_drop_extent_cache(inode, async_extent->start,
async_extent->start +
async_extent->ram_size - 1, 0);
em = alloc_extent_map(GFP_NOFS);
em->start = async_extent->start;
em->len = async_extent->ram_size;
@ -648,8 +662,6 @@ retry:
BTRFS_ORDERED_COMPRESSED);
BUG_ON(ret);
btrfs_end_transaction(trans, root);
/*
* clear dirty, set writeback and unlock the pages.
*/
@ -671,13 +683,11 @@ retry:
async_extent->nr_pages);
BUG_ON(ret);
trans = btrfs_join_transaction(root, 1);
alloc_hint = ins.objectid + ins.offset;
kfree(async_extent);
cond_resched();
}
btrfs_end_transaction(trans, root);
return 0;
}
@ -741,6 +751,7 @@ static noinline int cow_file_range(struct inode *inode,
EXTENT_CLEAR_DIRTY |
EXTENT_SET_WRITEBACK |
EXTENT_END_WRITEBACK);
*nr_written = *nr_written +
(end - start + PAGE_CACHE_SIZE) / PAGE_CACHE_SIZE;
*page_started = 1;
@ -1727,18 +1738,27 @@ static int btrfs_finish_ordered_io(struct inode *inode, u64 start, u64 end)
}
}
trans = btrfs_join_transaction(root, 1);
if (!ordered_extent)
ordered_extent = btrfs_lookup_ordered_extent(inode, start);
BUG_ON(!ordered_extent);
if (test_bit(BTRFS_ORDERED_NOCOW, &ordered_extent->flags))
goto nocow;
if (test_bit(BTRFS_ORDERED_NOCOW, &ordered_extent->flags)) {
BUG_ON(!list_empty(&ordered_extent->list));
ret = btrfs_ordered_update_i_size(inode, 0, ordered_extent);
if (!ret) {
trans = btrfs_join_transaction(root, 1);
ret = btrfs_update_inode(trans, root, inode);
BUG_ON(ret);
btrfs_end_transaction(trans, root);
}
goto out;
}
lock_extent(io_tree, ordered_extent->file_offset,
ordered_extent->file_offset + ordered_extent->len - 1,
GFP_NOFS);
trans = btrfs_join_transaction(root, 1);
if (test_bit(BTRFS_ORDERED_COMPRESSED, &ordered_extent->flags))
compressed = 1;
if (test_bit(BTRFS_ORDERED_PREALLOC, &ordered_extent->flags)) {
@ -1765,22 +1785,20 @@ static int btrfs_finish_ordered_io(struct inode *inode, u64 start, u64 end)
unlock_extent(io_tree, ordered_extent->file_offset,
ordered_extent->file_offset + ordered_extent->len - 1,
GFP_NOFS);
nocow:
add_pending_csums(trans, inode, ordered_extent->file_offset,
&ordered_extent->list);
mutex_lock(&BTRFS_I(inode)->extent_mutex);
btrfs_ordered_update_i_size(inode, ordered_extent);
btrfs_update_inode(trans, root, inode);
btrfs_remove_ordered_extent(inode, ordered_extent);
mutex_unlock(&BTRFS_I(inode)->extent_mutex);
/* this also removes the ordered extent from the tree */
btrfs_ordered_update_i_size(inode, 0, ordered_extent);
ret = btrfs_update_inode(trans, root, inode);
BUG_ON(ret);
btrfs_end_transaction(trans, root);
out:
/* once for us */
btrfs_put_ordered_extent(ordered_extent);
/* once for the tree */
btrfs_put_ordered_extent(ordered_extent);
btrfs_end_transaction(trans, root);
return 0;
}
@ -3562,7 +3580,6 @@ static noinline void init_btrfs_i(struct inode *inode)
INIT_LIST_HEAD(&BTRFS_I(inode)->ordered_operations);
RB_CLEAR_NODE(&BTRFS_I(inode)->rb_node);
btrfs_ordered_inode_tree_init(&BTRFS_I(inode)->ordered_tree);
mutex_init(&BTRFS_I(inode)->extent_mutex);
mutex_init(&BTRFS_I(inode)->log_mutex);
}

105
fs/btrfs/ordered-data.c
View File

@ -291,16 +291,16 @@ int btrfs_put_ordered_extent(struct btrfs_ordered_extent *entry)
/*
* remove an ordered extent from the tree. No references are dropped
* but, anyone waiting on this extent is woken up.
* and you must wake_up entry->wait. You must hold the tree mutex
* while you call this function.
*/
int btrfs_remove_ordered_extent(struct inode *inode,
static int __btrfs_remove_ordered_extent(struct inode *inode,
struct btrfs_ordered_extent *entry)
{
struct btrfs_ordered_inode_tree *tree;
struct rb_node *node;
tree = &BTRFS_I(inode)->ordered_tree;
mutex_lock(&tree->mutex);
node = &entry->rb_node;
rb_erase(node, &tree->tree);
tree->last = NULL;
@ -326,9 +326,26 @@ int btrfs_remove_ordered_extent(struct inode *inode,
}
spin_unlock(&BTRFS_I(inode)->root->fs_info->ordered_extent_lock);
return 0;
}
/*
* remove an ordered extent from the tree. No references are dropped
* but any waiters are woken.
*/
int btrfs_remove_ordered_extent(struct inode *inode,
struct btrfs_ordered_extent *entry)
{
struct btrfs_ordered_inode_tree *tree;
int ret;
tree = &BTRFS_I(inode)->ordered_tree;
mutex_lock(&tree->mutex);
ret = __btrfs_remove_ordered_extent(inode, entry);
mutex_unlock(&tree->mutex);
wake_up(&entry->wait);
return 0;
return ret;
}
/*
@ -589,7 +606,7 @@ out:
* After an extent is done, call this to conditionally update the on disk
* i_size. i_size is updated to cover any fully written part of the file.
*/
int btrfs_ordered_update_i_size(struct inode *inode,
int btrfs_ordered_update_i_size(struct inode *inode, u64 offset,
struct btrfs_ordered_extent *ordered)
{
struct btrfs_ordered_inode_tree *tree = &BTRFS_I(inode)->ordered_tree;
@ -597,18 +614,30 @@ int btrfs_ordered_update_i_size(struct inode *inode,
u64 disk_i_size;
u64 new_i_size;
u64 i_size_test;
u64 i_size = i_size_read(inode);
struct rb_node *node;
struct rb_node *prev = NULL;
struct btrfs_ordered_extent *test;
int ret = 1;
if (ordered)
offset = entry_end(ordered);
mutex_lock(&tree->mutex);
disk_i_size = BTRFS_I(inode)->disk_i_size;
/* truncate file */
if (disk_i_size > i_size) {
BTRFS_I(inode)->disk_i_size = i_size;
ret = 0;
goto out;
}
/*
* if the disk i_size is already at the inode->i_size, or
* this ordered extent is inside the disk i_size, we're done
*/
if (disk_i_size >= inode->i_size ||
ordered->file_offset + ordered->len <= disk_i_size) {
if (disk_i_size == i_size || offset <= disk_i_size) {
goto out;
}
@ -616,8 +645,7 @@ int btrfs_ordered_update_i_size(struct inode *inode,
* we can't update the disk_isize if there are delalloc bytes
* between disk_i_size and this ordered extent
*/
if (test_range_bit(io_tree, disk_i_size,
ordered->file_offset + ordered->len - 1,
if (test_range_bit(io_tree, disk_i_size, offset - 1,
EXTENT_DELALLOC, 0, NULL)) {
goto out;
}
@ -626,20 +654,32 @@ int btrfs_ordered_update_i_size(struct inode *inode,
* if we find an ordered extent then we can't update disk i_size
* yet
*/
node = &ordered->rb_node;
while (1) {
node = rb_prev(node);
if (!node)
break;
if (ordered) {
node = rb_prev(&ordered->rb_node);
} else {
prev = tree_search(tree, offset);
/*
* we insert file extents without involving ordered struct,
* so there should be no ordered struct cover this offset
*/
if (prev) {
test = rb_entry(prev, struct btrfs_ordered_extent,
rb_node);
BUG_ON(offset_in_entry(test, offset));
}
node = prev;
}
while (node) {
test = rb_entry(node, struct btrfs_ordered_extent, rb_node);
if (test->file_offset + test->len <= disk_i_size)
break;
if (test->file_offset >= inode->i_size)
if (test->file_offset >= i_size)
break;
if (test->file_offset >= disk_i_size)
goto out;
node = rb_prev(node);
}
new_i_size = min_t(u64, entry_end(ordered), i_size_read(inode));
new_i_size = min_t(u64, offset, i_size);
/*
* at this point, we know we can safely update i_size to at least
@ -647,7 +687,14 @@ int btrfs_ordered_update_i_size(struct inode *inode,
* walk forward and see if ios from higher up in the file have
* finished.
*/
node = rb_next(&ordered->rb_node);
if (ordered) {
node = rb_next(&ordered->rb_node);
} else {
if (prev)
node = rb_next(prev);
else
node = rb_first(&tree->tree);
}
i_size_test = 0;
if (node) {
/*
@ -655,10 +702,10 @@ int btrfs_ordered_update_i_size(struct inode *inode,
* between our ordered extent and the next one.
*/
test = rb_entry(node, struct btrfs_ordered_extent, rb_node);
if (test->file_offset > entry_end(ordered))
if (test->file_offset > offset)
i_size_test = test->file_offset;
} else {
i_size_test = i_size_read(inode);
i_size_test = i_size;
}
/*
@ -667,15 +714,25 @@ int btrfs_ordered_update_i_size(struct inode *inode,
* are no delalloc bytes in this area, it is safe to update
* disk_i_size to the end of the region.
*/
if (i_size_test > entry_end(ordered) &&
!test_range_bit(io_tree, entry_end(ordered), i_size_test - 1,
EXTENT_DELALLOC, 0, NULL)) {
new_i_size = min_t(u64, i_size_test, i_size_read(inode));
if (i_size_test > offset &&
!test_range_bit(io_tree, offset, i_size_test - 1,
EXTENT_DELALLOC, 0, NULL)) {
new_i_size = min_t(u64, i_size_test, i_size);
}
BTRFS_I(inode)->disk_i_size = new_i_size;
ret = 0;
out:
/*
* we need to remove the ordered extent with the tree lock held
* so that other people calling this function don't find our fully
* processed ordered entry and skip updating the i_size
*/
if (ordered)
__btrfs_remove_ordered_extent(inode, ordered);
mutex_unlock(&tree->mutex);
return 0;
if (ordered)
wake_up(&ordered->wait);
return ret;
}
/*

2
fs/btrfs/ordered-data.h
View File

@ -150,7 +150,7 @@ void btrfs_start_ordered_extent(struct inode *inode,
int btrfs_wait_ordered_range(struct inode *inode, u64 start, u64 len);
struct btrfs_ordered_extent *
btrfs_lookup_first_ordered_extent(struct inode * inode, u64 file_offset);
int btrfs_ordered_update_i_size(struct inode *inode,
int btrfs_ordered_update_i_size(struct inode *inode, u64 offset,
struct btrfs_ordered_extent *ordered);
int btrfs_find_ordered_sum(struct inode *inode, u64 offset, u64 disk_bytenr, u32 *sum);
int btrfs_wait_ordered_extents(struct btrfs_root *root, int nocow_only);