From 57f0f512b273f60d52568b8c6b77e17f5636edc0 Mon Sep 17 00:00:00 2001 From: André Fabian Silva Delgado Date: Wed, 5 Aug 2015 17:04:01 -0300 Subject: Initial import --- fs/nilfs2/gcinode.c | 197 ++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 197 insertions(+) create mode 100644 fs/nilfs2/gcinode.c (limited to 'fs/nilfs2/gcinode.c') diff --git a/fs/nilfs2/gcinode.c b/fs/nilfs2/gcinode.c new file mode 100644 index 000000000..748ca2389 --- /dev/null +++ b/fs/nilfs2/gcinode.c @@ -0,0 +1,197 @@ +/* + * gcinode.c - dummy inodes to buffer blocks for garbage collection + * + * Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA + * + * Written by Seiji Kihara , Amagai Yoshiji , + * and Ryusuke Konishi . + * Revised by Ryusuke Konishi . + * + */ +/* + * This file adds the cache of on-disk blocks to be moved in garbage + * collection. The disk blocks are held with dummy inodes (called + * gcinodes), and this file provides lookup function of the dummy + * inodes and their buffer read function. + * + * Buffers and pages held by the dummy inodes will be released each + * time after they are copied to a new log. Dirty blocks made on the + * current generation and the blocks to be moved by GC never overlap + * because the dirty blocks make a new generation; they rather must be + * written individually. + */ + +#include +#include +#include +#include +#include +#include "nilfs.h" +#include "btree.h" +#include "btnode.h" +#include "page.h" +#include "mdt.h" +#include "dat.h" +#include "ifile.h" + +/* + * nilfs_gccache_submit_read_data() - add data buffer and submit read request + * @inode - gc inode + * @blkoff - dummy offset treated as the key for the page cache + * @pbn - physical block number of the block + * @vbn - virtual block number of the block, 0 for non-virtual block + * @out_bh - indirect pointer to a buffer_head struct to receive the results + * + * Description: nilfs_gccache_submit_read_data() registers the data buffer + * specified by @pbn to the GC pagecache with the key @blkoff. + * This function sets @vbn (@pbn if @vbn is zero) in b_blocknr of the buffer. + * + * Return Value: On success, 0 is returned. On Error, one of the following + * negative error code is returned. + * + * %-EIO - I/O error. + * + * %-ENOMEM - Insufficient amount of memory available. + * + * %-ENOENT - The block specified with @pbn does not exist. + */ +int nilfs_gccache_submit_read_data(struct inode *inode, sector_t blkoff, + sector_t pbn, __u64 vbn, + struct buffer_head **out_bh) +{ + struct buffer_head *bh; + int err; + + bh = nilfs_grab_buffer(inode, inode->i_mapping, blkoff, 0); + if (unlikely(!bh)) + return -ENOMEM; + + if (buffer_uptodate(bh)) + goto out; + + if (pbn == 0) { + struct the_nilfs *nilfs = inode->i_sb->s_fs_info; + + err = nilfs_dat_translate(nilfs->ns_dat, vbn, &pbn); + if (unlikely(err)) { /* -EIO, -ENOMEM, -ENOENT */ + brelse(bh); + goto failed; + } + } + + lock_buffer(bh); + if (buffer_uptodate(bh)) { + unlock_buffer(bh); + goto out; + } + + if (!buffer_mapped(bh)) { + bh->b_bdev = inode->i_sb->s_bdev; + set_buffer_mapped(bh); + } + bh->b_blocknr = pbn; + bh->b_end_io = end_buffer_read_sync; + get_bh(bh); + submit_bh(READ, bh); + if (vbn) + bh->b_blocknr = vbn; + out: + err = 0; + *out_bh = bh; + + failed: + unlock_page(bh->b_page); + page_cache_release(bh->b_page); + return err; +} + +/* + * nilfs_gccache_submit_read_node() - add node buffer and submit read request + * @inode - gc inode + * @pbn - physical block number for the block + * @vbn - virtual block number for the block + * @out_bh - indirect pointer to a buffer_head struct to receive the results + * + * Description: nilfs_gccache_submit_read_node() registers the node buffer + * specified by @vbn to the GC pagecache. @pbn can be supplied by the + * caller to avoid translation of the disk block address. + * + * Return Value: On success, 0 is returned. On Error, one of the following + * negative error code is returned. + * + * %-EIO - I/O error. + * + * %-ENOMEM - Insufficient amount of memory available. + */ +int nilfs_gccache_submit_read_node(struct inode *inode, sector_t pbn, + __u64 vbn, struct buffer_head **out_bh) +{ + int ret; + + ret = nilfs_btnode_submit_block(&NILFS_I(inode)->i_btnode_cache, + vbn ? : pbn, pbn, READ, out_bh, &pbn); + if (ret == -EEXIST) /* internal code (cache hit) */ + ret = 0; + return ret; +} + +int nilfs_gccache_wait_and_mark_dirty(struct buffer_head *bh) +{ + wait_on_buffer(bh); + if (!buffer_uptodate(bh)) + return -EIO; + if (buffer_dirty(bh)) + return -EEXIST; + + if (buffer_nilfs_node(bh) && nilfs_btree_broken_node_block(bh)) { + clear_buffer_uptodate(bh); + return -EIO; + } + mark_buffer_dirty(bh); + return 0; +} + +int nilfs_init_gcinode(struct inode *inode) +{ + struct nilfs_inode_info *ii = NILFS_I(inode); + + inode->i_mode = S_IFREG; + mapping_set_gfp_mask(inode->i_mapping, GFP_NOFS); + inode->i_mapping->a_ops = &empty_aops; + + ii->i_flags = 0; + nilfs_bmap_init_gc(ii->i_bmap); + + return 0; +} + +/** + * nilfs_remove_all_gcinodes() - remove all unprocessed gc inodes + */ +void nilfs_remove_all_gcinodes(struct the_nilfs *nilfs) +{ + struct list_head *head = &nilfs->ns_gc_inodes; + struct nilfs_inode_info *ii; + + while (!list_empty(head)) { + ii = list_first_entry(head, struct nilfs_inode_info, i_dirty); + list_del_init(&ii->i_dirty); + truncate_inode_pages(&ii->vfs_inode.i_data, 0); + nilfs_btnode_cache_clear(&ii->i_btnode_cache); + iput(&ii->vfs_inode); + } +} -- cgit v1.2.3-54-g00ecf