return 0;
}
+ if (trans->aborted)
+ return 0;
again:
inode = lookup_free_space_inode(root, block_group, path);
if (IS_ERR(inode) && PTR_ERR(inode) != -ENOENT) {
*/
BTRFS_I(inode)->generation = 0;
ret = btrfs_update_inode(trans, root, inode);
+ if (ret) {
+ /*
+ * So theoretically we could recover from this, simply set the
+ * super cache generation to 0 so we know to invalidate the
+ * cache, but then we'd have to keep track of the block groups
+ * that fail this way so we know we _have_ to reset this cache
+ * before the next commit or risk reading stale cache. So to
+ * limit our exposure to horrible edge cases lets just abort the
+ * transaction, this only happens in really bad situations
+ * anyway.
+ */
+ btrfs_abort_transaction(trans, root, ret);
+ goto out_put;
+ }
WARN_ON(ret);
if (i_size_read(inode) > 0) {
* are still on the list after taking the semaphore
*/
list_del_init(&block_group->list);
- list_del_init(&block_group->ro_list);
if (list_empty(&block_group->space_info->block_groups[index])) {
kobj = block_group->space_info->block_group_kobjs[index];
block_group->space_info->block_group_kobjs[index] = NULL;
btrfs_remove_free_space_cache(block_group);
spin_lock(&block_group->space_info->lock);
+ list_del_init(&block_group->ro_list);
block_group->space_info->total_bytes -= block_group->key.offset;
block_group->space_info->bytes_readonly -= block_group->key.offset;
block_group->space_info->disk_total -= block_group->key.offset * factor;
mutex_lock(&inode->i_mutex);
- current->backing_dev_info = inode->i_mapping->backing_dev_info;
+ current->backing_dev_info = inode_to_bdi(inode);
err = generic_write_checks(file, &pos, &count, S_ISBLK(inode->i_mode));
if (err) {
mutex_unlock(&inode->i_mutex);
mutex_unlock(&inode->i_mutex);
/*
- * we want to make sure fsync finds this change
- * but we haven't joined a transaction running right now.
- *
- * Later on, someone is sure to update the inode and get the
- * real transid recorded.
- *
- * We set last_trans now to the fs_info generation + 1,
- * this will either be one more than the running transaction
- * or the generation used for the next transaction if there isn't
- * one running right now.
- *
* We also have to set last_sub_trans to the current log transid,
* otherwise subsequent syncs to a file that's been synced in this
* transaction will appear to have already occured.
*/
- BTRFS_I(inode)->last_trans = root->fs_info->generation + 1;
BTRFS_I(inode)->last_sub_trans = root->log_transid;
if (num_written > 0) {
err = generic_write_sync(file, pos, num_written);
atomic_inc(&root->log_batch);
/*
- * check the transaction that last modified this inode
- * and see if its already been committed
- */
- if (!BTRFS_I(inode)->last_trans) {
- mutex_unlock(&inode->i_mutex);
- goto out;
- }
-
- /*
- * if the last transaction that changed this file was before
- * the current transaction, we can bail out now without any
- * syncing
+ * If the last transaction that changed this file was before the current
+ * transaction and we have the full sync flag set in our inode, we can
+ * bail out now without any syncing.
+ *
+ * Note that we can't bail out if the full sync flag isn't set. This is
+ * because when the full sync flag is set we start all ordered extents
+ * and wait for them to fully complete - when they complete they update
+ * the inode's last_trans field through:
+ *
+ * btrfs_finish_ordered_io() ->
+ * btrfs_update_inode_fallback() ->
+ * btrfs_update_inode() ->
+ * btrfs_set_inode_last_trans()
+ *
+ * So we are sure that last_trans is up to date and can do this check to
+ * bail out safely. For the fast path, when the full sync flag is not
+ * set in our inode, we can not do it because we start only our ordered
+ * extents and don't wait for them to complete (that is when
+ * btrfs_finish_ordered_io runs), so here at this point their last_trans
+ * value might be less than or equals to fs_info->last_trans_committed,
+ * and setting a speculative last_trans for an inode when a buffered
+ * write is made (such as fs_info->generation + 1 for example) would not
+ * be reliable since after setting the value and before fsync is called
+ * any number of transactions can start and commit (transaction kthread
+ * commits the current transaction periodically), and a transaction
+ * commit does not start nor waits for ordered extents to complete.
*/
smp_mb();
if (btrfs_inode_in_log(inode, root->fs_info->generation) ||
- BTRFS_I(inode)->last_trans <=
- root->fs_info->last_trans_committed) {
- BTRFS_I(inode)->last_trans = 0;
-
+ (full_sync && BTRFS_I(inode)->last_trans <=
+ root->fs_info->last_trans_committed)) {
/*
* We'v had everything committed since the last time we were
* modified so clear this flag in case it was set for whatever
.fault = filemap_fault,
.map_pages = filemap_map_pages,
.page_mkwrite = btrfs_page_mkwrite,
- .remap_pages = generic_file_remap_pages,
};
static int btrfs_file_mmap(struct file *filp, struct vm_area_struct *vma)
bool same_page;
bool no_holes = btrfs_fs_incompat(root->fs_info, NO_HOLES);
u64 ino_size;
+ bool truncated_page = false;
+ bool updated_inode = false;
ret = btrfs_wait_ordered_range(inode, offset, len);
if (ret)
* entire page.
*/
if (same_page && len < PAGE_CACHE_SIZE) {
- if (offset < ino_size)
+ if (offset < ino_size) {
+ truncated_page = true;
ret = btrfs_truncate_page(inode, offset, len, 0);
+ } else {
+ ret = 0;
+ }
goto out_only_mutex;
}
/* zero back part of the first page */
if (offset < ino_size) {
+ truncated_page = true;
ret = btrfs_truncate_page(inode, offset, 0, 0);
if (ret) {
mutex_unlock(&inode->i_mutex);
if (!ret) {
/* zero the front end of the last page */
if (tail_start + tail_len < ino_size) {
+ truncated_page = true;
ret = btrfs_truncate_page(inode,
tail_start + tail_len, 0, 1);
if (ret)
}
if (lockend < lockstart) {
- mutex_unlock(&inode->i_mutex);
- return 0;
+ ret = 0;
+ goto out_only_mutex;
}
while (1) {
trans->block_rsv = &root->fs_info->trans_block_rsv;
ret = btrfs_update_inode(trans, root, inode);
+ updated_inode = true;
btrfs_end_transaction(trans, root);
btrfs_btree_balance_dirty(root);
out_free:
unlock_extent_cached(&BTRFS_I(inode)->io_tree, lockstart, lockend,
&cached_state, GFP_NOFS);
out_only_mutex:
+ if (!updated_inode && truncated_page && !ret && !err) {
+ /*
+ * If we only end up zeroing part of a page, we still need to
+ * update the inode item, so that all the time fields are
+ * updated as well as the necessary btrfs inode in memory fields
+ * for detecting, at fsync time, if the inode isn't yet in the
+ * log tree or it's there but not up to date.
+ */
+ trans = btrfs_start_transaction(root, 1);
+ if (IS_ERR(trans)) {
+ err = PTR_ERR(trans);
+ } else {
+ err = btrfs_update_inode(trans, root, inode);
+ ret = btrfs_end_transaction(trans, root);
+ }
+ }
mutex_unlock(&inode->i_mutex);
if (ret && !err)
err = ret;
switch (inode->i_mode & S_IFMT) {
case S_IFREG:
inode->i_mapping->a_ops = &btrfs_aops;
- inode->i_mapping->backing_dev_info = &root->fs_info->bdi;
BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops;
inode->i_fop = &btrfs_file_operations;
inode->i_op = &btrfs_file_inode_operations;
case S_IFLNK:
inode->i_op = &btrfs_symlink_inode_operations;
inode->i_mapping->a_ops = &btrfs_symlink_aops;
- inode->i_mapping->backing_dev_info = &root->fs_info->bdi;
break;
default:
inode->i_op = &btrfs_special_inode_operations;
inode->i_fop = &btrfs_file_operations;
inode->i_op = &btrfs_file_inode_operations;
inode->i_mapping->a_ops = &btrfs_aops;
- inode->i_mapping->backing_dev_info = &root->fs_info->bdi;
err = btrfs_init_inode_security(trans, inode, dir, &dentry->d_name);
if (err)
((BTRFS_I(inode)->flags & BTRFS_INODE_NODATACOW) &&
em->block_start != EXTENT_MAP_HOLE)) {
int type;
- int ret;
u64 block_start, orig_start, orig_block_len, ram_bytes;
if (test_bit(EXTENT_FLAG_PREALLOC, &em->flags))
inode->i_fop = &btrfs_file_operations;
inode->i_op = &btrfs_file_inode_operations;
inode->i_mapping->a_ops = &btrfs_aops;
- inode->i_mapping->backing_dev_info = &root->fs_info->bdi;
BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops;
err = btrfs_init_inode_security(trans, inode, dir, &dentry->d_name);
inode->i_op = &btrfs_symlink_inode_operations;
inode->i_mapping->a_ops = &btrfs_symlink_aops;
- inode->i_mapping->backing_dev_info = &root->fs_info->bdi;
inode_set_bytes(inode, name_len);
btrfs_i_size_write(inode, name_len);
err = btrfs_update_inode(trans, root, inode);
inode->i_op = &btrfs_file_inode_operations;
inode->i_mapping->a_ops = &btrfs_aops;
- inode->i_mapping->backing_dev_info = &root->fs_info->bdi;
BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops;
ret = btrfs_init_inode_security(trans, inode, dir, NULL);
projects / cascardo / linux.git / commitdiff