return em;
}
+static struct extent_map *btrfs_create_dio_extent(struct inode *inode,
+ const u64 start,
+ const u64 len,
+ const u64 orig_start,
+ const u64 block_start,
+ const u64 block_len,
+ const u64 orig_block_len,
+ const u64 ram_bytes,
+ const int type)
+{
+ struct extent_map *em = NULL;
+ int ret;
+
+ down_read(&BTRFS_I(inode)->dio_sem);
+ if (type != BTRFS_ORDERED_NOCOW) {
+ em = create_pinned_em(inode, start, len, orig_start,
+ block_start, block_len, orig_block_len,
+ ram_bytes, type);
+ if (IS_ERR(em))
+ goto out;
+ }
+ ret = btrfs_add_ordered_extent_dio(inode, start, block_start,
+ len, block_len, type);
+ if (ret) {
+ if (em) {
+ free_extent_map(em);
+ btrfs_drop_extent_cache(inode, start,
+ start + len - 1, 0);
+ }
+ em = ERR_PTR(ret);
+ }
+ out:
+ up_read(&BTRFS_I(inode)->dio_sem);
+
+ return em;
+}
+
static struct extent_map *btrfs_new_extent_direct(struct inode *inode,
u64 start, u64 len)
{
if (ret)
return ERR_PTR(ret);
- /*
- * Create the ordered extent before the extent map. This is to avoid
- * races with the fast fsync path that would lead to it logging file
- * extent items that point to disk extents that were not yet written to.
- * The fast fsync path collects ordered extents into a local list and
- * then collects all the new extent maps, so we must create the ordered
- * extent first and make sure the fast fsync path collects any new
- * ordered extents after collecting new extent maps as well.
- * The fsync path simply can not rely on inode_dio_wait() because it
- * causes deadlock with AIO.
- */
- ret = btrfs_add_ordered_extent_dio(inode, start, ins.objectid,
- ins.offset, ins.offset, 0);
- if (ret) {
- btrfs_free_reserved_extent(root, ins.objectid, ins.offset, 1);
- return ERR_PTR(ret);
- }
-
+ em = btrfs_create_dio_extent(inode, start, ins.offset, start,
+ ins.objectid, ins.offset, ins.offset,
+ ins.offset, 0);
btrfs_dec_block_group_reservations(root->fs_info, ins.objectid);
-
- em = create_pinned_em(inode, start, ins.offset, start, ins.objectid,
- ins.offset, ins.offset, ins.offset, 0);
- if (IS_ERR(em)) {
- struct btrfs_ordered_extent *oe;
-
+ if (IS_ERR(em))
btrfs_free_reserved_extent(root, ins.objectid, ins.offset, 1);
- oe = btrfs_lookup_ordered_extent(inode, start);
- ASSERT(oe);
- if (WARN_ON(!oe))
- return em;
- set_bit(BTRFS_ORDERED_IOERR, &oe->flags);
- set_bit(BTRFS_ORDERED_IO_DONE, &oe->flags);
- btrfs_remove_ordered_extent(inode, oe);
- /* Once for our lookup and once for the ordered extents tree. */
- btrfs_put_ordered_extent(oe);
- btrfs_put_ordered_extent(oe);
- }
+
return em;
}
if (can_nocow_extent(inode, start, &len, &orig_start,
&orig_block_len, &ram_bytes) == 1 &&
btrfs_inc_nocow_writers(root->fs_info, block_start)) {
+ struct extent_map *em2;
- /*
- * Create the ordered extent before the extent map. This
- * is to avoid races with the fast fsync path because it
- * collects ordered extents into a local list and then
- * collects all the new extent maps, so we must create
- * the ordered extent first and make sure the fast fsync
- * path collects any new ordered extents after
- * collecting new extent maps as well. The fsync path
- * simply can not rely on inode_dio_wait() because it
- * causes deadlock with AIO.
- */
- ret = btrfs_add_ordered_extent_dio(inode, start,
- block_start, len, len, type);
+ em2 = btrfs_create_dio_extent(inode, start, len,
+ orig_start, block_start,
+ len, orig_block_len,
+ ram_bytes, type);
btrfs_dec_nocow_writers(root->fs_info, block_start);
- if (ret) {
- free_extent_map(em);
- goto unlock_err;
- }
-
if (type == BTRFS_ORDERED_PREALLOC) {
free_extent_map(em);
- em = create_pinned_em(inode, start, len,
- orig_start,
- block_start, len,
- orig_block_len,
- ram_bytes, type);
- if (IS_ERR(em)) {
- struct btrfs_ordered_extent *oe;
-
- ret = PTR_ERR(em);
- oe = btrfs_lookup_ordered_extent(inode,
- start);
- ASSERT(oe);
- if (WARN_ON(!oe))
- goto unlock_err;
- set_bit(BTRFS_ORDERED_IOERR,
- &oe->flags);
- set_bit(BTRFS_ORDERED_IO_DONE,
- &oe->flags);
- btrfs_remove_ordered_extent(inode, oe);
- /*
- * Once for our lookup and once for the
- * ordered extents tree.
- */
- btrfs_put_ordered_extent(oe);
- btrfs_put_ordered_extent(oe);
- goto unlock_err;
- }
+ em = em2;
+ }
+ if (em2 && IS_ERR(em2)) {
+ ret = PTR_ERR(em2);
+ goto unlock_err;
}
-
goto unlock;
}
}
INIT_LIST_HEAD(&ei->delalloc_inodes);
INIT_LIST_HEAD(&ei->delayed_iput);
RB_CLEAR_NODE(&ei->rb_node);
+ init_rwsem(&ei->dio_sem);
return inode;
}
INIT_LIST_HEAD(&extents);
+ down_write(&BTRFS_I(inode)->dio_sem);
write_lock(&tree->lock);
test_gen = root->fs_info->last_trans_committed;
}
list_sort(NULL, &extents, extent_cmp);
+ btrfs_get_logged_extents(inode, logged_list, start, end);
/*
- * Collect any new ordered extents within the range. This is to
- * prevent logging file extent items without waiting for the disk
- * location they point to being written. We do this only to deal
- * with races against concurrent lockless direct IO writes.
+ * Some ordered extents started by fsync might have completed
+ * before we could collect them into the list logged_list, which
+ * means they're gone, not in our logged_list nor in the inode's
+ * ordered tree. We want the application/user space to know an
+ * error happened while attempting to persist file data so that
+ * it can take proper action. If such error happened, we leave
+ * without writing to the log tree and the fsync must report the
+ * file data write error and not commit the current transaction.
*/
- btrfs_get_logged_extents(inode, logged_list, start, end);
+ ret = btrfs_inode_check_errors(inode);
+ if (ret)
+ ctx->io_err = ret;
process:
while (!list_empty(&extents)) {
em = list_entry(extents.next, struct extent_map, list);
}
WARN_ON(!list_empty(&extents));
write_unlock(&tree->lock);
+ up_write(&BTRFS_I(inode)->dio_sem);
btrfs_release_path(path);
return ret;
mutex_lock(&BTRFS_I(inode)->log_mutex);
- /*
- * Collect ordered extents only if we are logging data. This is to
- * ensure a subsequent request to log this inode in LOG_INODE_ALL mode
- * will process the ordered extents if they still exists at the time,
- * because when we collect them we test and set for the flag
- * BTRFS_ORDERED_LOGGED to prevent multiple log requests to process the
- * same ordered extents. The consequence for the LOG_INODE_ALL log mode
- * not processing the ordered extents is that we end up logging the
- * corresponding file extent items, based on the extent maps in the
- * inode's extent_map_tree's modified_list, without logging the
- * respective checksums (since the may still be only attached to the
- * ordered extents and have not been inserted in the csum tree by
- * btrfs_finish_ordered_io() yet).
- */
- if (inode_only == LOG_INODE_ALL)
- btrfs_get_logged_extents(inode, &logged_list, start, end);
-
/*
* a brute force approach to making sure we get the most uptodate
* copies of everything.
goto out_unlock;
}
if (fast_search) {
- /*
- * Some ordered extents started by fsync might have completed
- * before we collected the ordered extents in logged_list, which
- * means they're gone, not in our logged_list nor in the inode's
- * ordered tree. We want the application/user space to know an
- * error happened while attempting to persist file data so that
- * it can take proper action. If such error happened, we leave
- * without writing to the log tree and the fsync must report the
- * file data write error and not commit the current transaction.
- */
- err = btrfs_inode_check_errors(inode);
- if (err) {
- ctx->io_err = err;
- goto out_unlock;
- }
ret = btrfs_log_changed_extents(trans, root, inode, dst_path,
&logged_list, ctx, start, end);
if (ret) {
projects / cascardo / linux.git / commitdiff