From: Stephen Rothwell Date: Thu, 11 Feb 2016 04:34:56 +0000 (+1100) Subject: Merge branch 'akpm-current/current' X-Git-Tag: next-20160211~2 X-Git-Url: https://git.karo-electronics.de/?p=karo-tx-linux.git;a=commitdiff_plain;h=74256136ec779b263d93a0566c2dc5ca3598d2e5 Merge branch 'akpm-current/current' --- 74256136ec779b263d93a0566c2dc5ca3598d2e5 diff --cc fs/ocfs2/aops.c index 5dcc5f5a842e,3d3952ebe101..56ce3704d66f --- a/fs/ocfs2/aops.c +++ b/fs/ocfs2/aops.c @@@ -2476,6 -2099,356 +2099,361 @@@ static int ocfs2_write_end(struct file return ret; } + struct ocfs2_dio_write_ctxt { + struct list_head dw_zero_list; + unsigned dw_zero_count; + int dw_orphaned; + pid_t dw_writer_pid; + }; + + static struct ocfs2_dio_write_ctxt * + ocfs2_dio_alloc_write_ctx(struct buffer_head *bh, int *alloc) + { + struct ocfs2_dio_write_ctxt *dwc = NULL; + + if (bh->b_private) + return bh->b_private; + + dwc = kmalloc(sizeof(struct ocfs2_dio_write_ctxt), GFP_NOFS); + if (dwc == NULL) + return NULL; + INIT_LIST_HEAD(&dwc->dw_zero_list); + dwc->dw_zero_count = 0; + dwc->dw_orphaned = 0; + dwc->dw_writer_pid = task_pid_nr(current); + bh->b_private = dwc; + *alloc = 1; + + return dwc; + } + + static void ocfs2_dio_free_write_ctx(struct inode *inode, + struct ocfs2_dio_write_ctxt *dwc) + { + ocfs2_free_unwritten_list(inode, &dwc->dw_zero_list); + kfree(dwc); + } + + /* + * TODO: Make this into a generic get_blocks function. + * + * From do_direct_io in direct-io.c: + * "So what we do is to permit the ->get_blocks function to populate + * bh.b_size with the size of IO which is permitted at this offset and + * this i_blkbits." + * + * This function is called directly from get_more_blocks in direct-io.c. + * + * called like this: dio->get_blocks(dio->inode, fs_startblk, + * fs_count, map_bh, dio->rw == WRITE); + */ + static int ocfs2_dio_get_block(struct inode *inode, sector_t iblock, + struct buffer_head *bh_result, int create) + { + struct ocfs2_super *osb = OCFS2_SB(inode->i_sb); + struct ocfs2_inode_info *oi = OCFS2_I(inode); + struct ocfs2_write_ctxt *wc; + struct ocfs2_write_cluster_desc *desc = NULL; + struct ocfs2_dio_write_ctxt *dwc = NULL; + struct buffer_head *di_bh = NULL; + u64 p_blkno; + loff_t pos = iblock << inode->i_sb->s_blocksize_bits; + unsigned len, total_len = bh_result->b_size; + int ret = 0, first_get_block = 0; + + len = osb->s_clustersize - (pos & (osb->s_clustersize - 1)); + len = min(total_len, len); + + mlog(0, "get block of %lu at %llu:%u req %u\n", + inode->i_ino, pos, len, total_len); + + /* + * Because we need to change file size in ocfs2_dio_end_io_write(), or + * we may need to add it to orphan dir. So can not fall to fast path + * while file size will be changed. + */ + if (pos + total_len <= i_size_read(inode)) { + down_read(&oi->ip_alloc_sem); + /* This is the fast path for re-write. */ + ret = ocfs2_get_block(inode, iblock, bh_result, create); + + up_read(&oi->ip_alloc_sem); + + if (buffer_mapped(bh_result) && + !buffer_new(bh_result) && + ret == 0) + goto out; + + /* Clear state set by ocfs2_get_block. */ + bh_result->b_state = 0; + } + + dwc = ocfs2_dio_alloc_write_ctx(bh_result, &first_get_block); + if (unlikely(dwc == NULL)) { + ret = -ENOMEM; + mlog_errno(ret); + goto out; + } + + if (ocfs2_clusters_for_bytes(inode->i_sb, pos + total_len) > + ocfs2_clusters_for_bytes(inode->i_sb, i_size_read(inode)) && + !dwc->dw_orphaned) { + /* + * when we are going to alloc extents beyond file size, add the + * inode to orphan dir, so we can recall those spaces when + * system crashed during write. + */ + ret = ocfs2_add_inode_to_orphan(osb, inode); + if (ret < 0) { + mlog_errno(ret); + goto out; + } + dwc->dw_orphaned = 1; + } + + ret = ocfs2_inode_lock(inode, &di_bh, 1); + if (ret) { + mlog_errno(ret); + goto out; + } + + down_write(&oi->ip_alloc_sem); + + if (first_get_block) { + if (ocfs2_sparse_alloc(OCFS2_SB(inode->i_sb))) + ret = ocfs2_zero_tail(inode, di_bh, pos); + else + ret = ocfs2_expand_nonsparse_inode(inode, di_bh, pos, + total_len, NULL); + if (ret < 0) { + mlog_errno(ret); + goto unlock; + } + } + + ret = ocfs2_write_begin_nolock(inode->i_mapping, pos, len, + OCFS2_WRITE_DIRECT, NULL, + (void **)&wc, di_bh, NULL); + if (ret) { + mlog_errno(ret); + goto unlock; + } + + desc = &wc->w_desc[0]; + + p_blkno = ocfs2_clusters_to_blocks(inode->i_sb, desc->c_phys); + BUG_ON(p_blkno == 0); + p_blkno += iblock & (u64)(ocfs2_clusters_to_blocks(inode->i_sb, 1) - 1); + + map_bh(bh_result, inode->i_sb, p_blkno); + bh_result->b_size = len; + if (desc->c_needs_zero) + set_buffer_new(bh_result); + + /* May sleep in end_io. It should not happen in a irq context. So defer + * it to dio work queue. */ + set_buffer_defer_completion(bh_result); + + if (!list_empty(&wc->w_unwritten_list)) { + struct ocfs2_unwritten_extent *ue = NULL; + + ue = list_first_entry(&wc->w_unwritten_list, + struct ocfs2_unwritten_extent, + ue_node); + BUG_ON(ue->ue_cpos != desc->c_cpos); + /* The physical address may be 0, fill it. */ + ue->ue_phys = desc->c_phys; + + list_splice_tail_init(&wc->w_unwritten_list, &dwc->dw_zero_list); + dwc->dw_zero_count++; + } + + ret = ocfs2_write_end_nolock(inode->i_mapping, pos, len, len, NULL, wc); + BUG_ON(ret != len); + ret = 0; + unlock: + up_write(&oi->ip_alloc_sem); + ocfs2_inode_unlock(inode, 1); + brelse(di_bh); + out: + if (ret < 0) + ret = -EIO; + return ret; + } + + static void ocfs2_dio_end_io_write(struct inode *inode, + struct ocfs2_dio_write_ctxt *dwc, + loff_t offset, + ssize_t bytes) + { + struct ocfs2_cached_dealloc_ctxt dealloc; + struct ocfs2_extent_tree et; + struct ocfs2_super *osb = OCFS2_SB(inode->i_sb); + struct ocfs2_inode_info *oi = OCFS2_I(inode); + struct ocfs2_unwritten_extent *ue = NULL; + struct buffer_head *di_bh = NULL; + struct ocfs2_dinode *di; + struct ocfs2_alloc_context *data_ac = NULL; + struct ocfs2_alloc_context *meta_ac = NULL; + handle_t *handle = NULL; + loff_t end = offset + bytes; + int ret = 0, credits = 0, locked = 0; + + ocfs2_init_dealloc_ctxt(&dealloc); + + /* We do clear unwritten, delete orphan, change i_size here. If neither + * of these happen, we can skip all this. */ + if (list_empty(&dwc->dw_zero_list) && + end <= i_size_read(inode) && + !dwc->dw_orphaned) + goto out; + + /* ocfs2_file_write_iter will get i_mutex, so we need not lock if we + * are in that context. */ + if (dwc->dw_writer_pid != task_pid_nr(current)) { + mutex_lock(&inode->i_mutex); + locked = 1; + } + + ret = ocfs2_inode_lock(inode, &di_bh, 1); + if (ret < 0) { + mlog_errno(ret); + goto out; + } + + down_write(&oi->ip_alloc_sem); + + /* Delete orphan before acquire i_mutex. */ + if (dwc->dw_orphaned) { + BUG_ON(dwc->dw_writer_pid != task_pid_nr(current)); + + end = end > i_size_read(inode) ? end : 0; + + ret = ocfs2_del_inode_from_orphan(osb, inode, di_bh, + !!end, end); + if (ret < 0) + mlog_errno(ret); + } + + di = (struct ocfs2_dinode *)di_bh; + + ocfs2_init_dinode_extent_tree(&et, INODE_CACHE(inode), di_bh); + + ret = ocfs2_lock_allocators(inode, &et, 0, dwc->dw_zero_count*2, + &data_ac, &meta_ac); + if (ret) { + mlog_errno(ret); + goto unlock; + } + + credits = ocfs2_calc_extend_credits(inode->i_sb, &di->id2.i_list); + + handle = ocfs2_start_trans(osb, credits); + if (IS_ERR(handle)) { + ret = PTR_ERR(handle); + mlog_errno(ret); + goto unlock; + } + ret = ocfs2_journal_access_di(handle, INODE_CACHE(inode), di_bh, + OCFS2_JOURNAL_ACCESS_WRITE); + if (ret) { + mlog_errno(ret); + goto commit; + } + + list_for_each_entry(ue, &dwc->dw_zero_list, ue_node) { + ret = ocfs2_mark_extent_written(inode, &et, handle, + ue->ue_cpos, 1, + ue->ue_phys, + meta_ac, &dealloc); + if (ret < 0) { + mlog_errno(ret); + break; + } + } + + if (end > i_size_read(inode)) { + ret = ocfs2_set_inode_size(handle, inode, di_bh, end); + if (ret < 0) + mlog_errno(ret); + } + commit: + ocfs2_commit_trans(osb, handle); + unlock: + up_write(&oi->ip_alloc_sem); + ocfs2_inode_unlock(inode, 1); + brelse(di_bh); + out: + if (data_ac) + ocfs2_free_alloc_context(data_ac); + if (meta_ac) + ocfs2_free_alloc_context(meta_ac); + ocfs2_run_deallocs(osb, &dealloc); + if (locked) + mutex_unlock(&inode->i_mutex); + ocfs2_dio_free_write_ctx(inode, dwc); + } + + /* + * ocfs2_dio_end_io is called by the dio core when a dio is finished. We're + * particularly interested in the aio/dio case. We use the rw_lock DLM lock + * to protect io on one node from truncation on another. + */ -static void ocfs2_dio_end_io(struct kiocb *iocb, - loff_t offset, - ssize_t bytes, - void *private) ++static int ocfs2_dio_end_io(struct kiocb *iocb, ++ loff_t offset, ++ ssize_t bytes, ++ void *private) + { + struct inode *inode = file_inode(iocb->ki_filp); + int level; + ++ if (bytes <= 0) ++ return 0; ++ + /* this io's submitter should not have unlocked this before we could */ + BUG_ON(!ocfs2_iocb_is_rw_locked(iocb)); + + if (private) + ocfs2_dio_end_io_write(inode, private, offset, bytes); + + ocfs2_iocb_clear_rw_locked(iocb); + + level = ocfs2_iocb_rw_locked_level(iocb); + ocfs2_rw_unlock(inode, level); ++ ++ return 0; + } + + static ssize_t ocfs2_direct_IO(struct kiocb *iocb, struct iov_iter *iter, + loff_t offset) + { + struct file *file = iocb->ki_filp; + struct inode *inode = file_inode(file)->i_mapping->host; + struct ocfs2_super *osb = OCFS2_SB(inode->i_sb); + loff_t end = offset + iter->count; + get_block_t *get_block; + + /* + * Fallback to buffered I/O if we see an inode without + * extents. + */ + if (OCFS2_I(inode)->ip_dyn_features & OCFS2_INLINE_DATA_FL) + return 0; + + /* Fallback to buffered I/O if we do not support append dio. */ + if (end > i_size_read(inode) && !ocfs2_supports_append_dio(osb)) + return 0; + + if (iov_iter_rw(iter) == READ) + get_block = ocfs2_get_block; + else + get_block = ocfs2_dio_get_block; + + return __blockdev_direct_IO(iocb, inode, inode->i_sb->s_bdev, + iter, offset, get_block, + ocfs2_dio_end_io, NULL, 0); + } + const struct address_space_operations ocfs2_aops = { .readpage = ocfs2_readpage, .readpages = ocfs2_readpages,