From 9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 Mon Sep 17 00:00:00 2001 From: Yunhong Jiang Date: Tue, 4 Aug 2015 12:17:53 -0700 Subject: Add the rt linux 4.1.3-rt3 as base Import the rt linux 4.1.3-rt3 as OPNFV kvm base. It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and the base is: commit 0917f823c59692d751951bf5ea699a2d1e2f26a2 Author: Sebastian Andrzej Siewior Date: Sat Jul 25 12:13:34 2015 +0200 Prepare v4.1.3-rt3 Signed-off-by: Sebastian Andrzej Siewior We lose all the git history this way and it's not good. We should apply another opnfv project repo in future. Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423 Signed-off-by: Yunhong Jiang --- kernel/fs/nilfs2/btnode.c | 297 ++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 297 insertions(+) create mode 100644 kernel/fs/nilfs2/btnode.c (limited to 'kernel/fs/nilfs2/btnode.c') diff --git a/kernel/fs/nilfs2/btnode.c b/kernel/fs/nilfs2/btnode.c new file mode 100644 index 000000000..a35ae35e6 --- /dev/null +++ b/kernel/fs/nilfs2/btnode.c @@ -0,0 +1,297 @@ +/* + * btnode.c - NILFS B-tree node cache + * + * 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 + * + * This file was originally written by Seiji Kihara + * and fully revised by Ryusuke Konishi for + * stabilization and simplification. + * + */ + +#include +#include +#include +#include +#include +#include "nilfs.h" +#include "mdt.h" +#include "dat.h" +#include "page.h" +#include "btnode.h" + +void nilfs_btnode_cache_clear(struct address_space *btnc) +{ + invalidate_mapping_pages(btnc, 0, -1); + truncate_inode_pages(btnc, 0); +} + +struct buffer_head * +nilfs_btnode_create_block(struct address_space *btnc, __u64 blocknr) +{ + struct inode *inode = NILFS_BTNC_I(btnc); + struct buffer_head *bh; + + bh = nilfs_grab_buffer(inode, btnc, blocknr, 1 << BH_NILFS_Node); + if (unlikely(!bh)) + return NULL; + + if (unlikely(buffer_mapped(bh) || buffer_uptodate(bh) || + buffer_dirty(bh))) { + brelse(bh); + BUG(); + } + memset(bh->b_data, 0, 1 << inode->i_blkbits); + bh->b_bdev = inode->i_sb->s_bdev; + bh->b_blocknr = blocknr; + set_buffer_mapped(bh); + set_buffer_uptodate(bh); + + unlock_page(bh->b_page); + page_cache_release(bh->b_page); + return bh; +} + +int nilfs_btnode_submit_block(struct address_space *btnc, __u64 blocknr, + sector_t pblocknr, int mode, + struct buffer_head **pbh, sector_t *submit_ptr) +{ + struct buffer_head *bh; + struct inode *inode = NILFS_BTNC_I(btnc); + struct page *page; + int err; + + bh = nilfs_grab_buffer(inode, btnc, blocknr, 1 << BH_NILFS_Node); + if (unlikely(!bh)) + return -ENOMEM; + + err = -EEXIST; /* internal code */ + page = bh->b_page; + + if (buffer_uptodate(bh) || buffer_dirty(bh)) + goto found; + + if (pblocknr == 0) { + pblocknr = blocknr; + if (inode->i_ino != NILFS_DAT_INO) { + struct the_nilfs *nilfs = inode->i_sb->s_fs_info; + + /* blocknr is a virtual block number */ + err = nilfs_dat_translate(nilfs->ns_dat, blocknr, + &pblocknr); + if (unlikely(err)) { + brelse(bh); + goto out_locked; + } + } + } + + if (mode == READA) { + if (pblocknr != *submit_ptr + 1 || !trylock_buffer(bh)) { + err = -EBUSY; /* internal code */ + brelse(bh); + goto out_locked; + } + } else { /* mode == READ */ + lock_buffer(bh); + } + if (buffer_uptodate(bh)) { + unlock_buffer(bh); + err = -EEXIST; /* internal code */ + goto found; + } + set_buffer_mapped(bh); + bh->b_bdev = inode->i_sb->s_bdev; + bh->b_blocknr = pblocknr; /* set block address for read */ + bh->b_end_io = end_buffer_read_sync; + get_bh(bh); + submit_bh(mode, bh); + bh->b_blocknr = blocknr; /* set back to the given block address */ + *submit_ptr = pblocknr; + err = 0; +found: + *pbh = bh; + +out_locked: + unlock_page(page); + page_cache_release(page); + return err; +} + +/** + * nilfs_btnode_delete - delete B-tree node buffer + * @bh: buffer to be deleted + * + * nilfs_btnode_delete() invalidates the specified buffer and delete the page + * including the buffer if the page gets unbusy. + */ +void nilfs_btnode_delete(struct buffer_head *bh) +{ + struct address_space *mapping; + struct page *page = bh->b_page; + pgoff_t index = page_index(page); + int still_dirty; + + page_cache_get(page); + lock_page(page); + wait_on_page_writeback(page); + + nilfs_forget_buffer(bh); + still_dirty = PageDirty(page); + mapping = page->mapping; + unlock_page(page); + page_cache_release(page); + + if (!still_dirty && mapping) + invalidate_inode_pages2_range(mapping, index, index); +} + +/** + * nilfs_btnode_prepare_change_key + * prepare to move contents of the block for old key to one of new key. + * the old buffer will not be removed, but might be reused for new buffer. + * it might return -ENOMEM because of memory allocation errors, + * and might return -EIO because of disk read errors. + */ +int nilfs_btnode_prepare_change_key(struct address_space *btnc, + struct nilfs_btnode_chkey_ctxt *ctxt) +{ + struct buffer_head *obh, *nbh; + struct inode *inode = NILFS_BTNC_I(btnc); + __u64 oldkey = ctxt->oldkey, newkey = ctxt->newkey; + int err; + + if (oldkey == newkey) + return 0; + + obh = ctxt->bh; + ctxt->newbh = NULL; + + if (inode->i_blkbits == PAGE_CACHE_SHIFT) { + lock_page(obh->b_page); + /* + * We cannot call radix_tree_preload for the kernels older + * than 2.6.23, because it is not exported for modules. + */ +retry: + err = radix_tree_preload(GFP_NOFS & ~__GFP_HIGHMEM); + if (err) + goto failed_unlock; + /* BUG_ON(oldkey != obh->b_page->index); */ + if (unlikely(oldkey != obh->b_page->index)) + NILFS_PAGE_BUG(obh->b_page, + "invalid oldkey %lld (newkey=%lld)", + (unsigned long long)oldkey, + (unsigned long long)newkey); + + spin_lock_irq(&btnc->tree_lock); + err = radix_tree_insert(&btnc->page_tree, newkey, obh->b_page); + spin_unlock_irq(&btnc->tree_lock); + /* + * Note: page->index will not change to newkey until + * nilfs_btnode_commit_change_key() will be called. + * To protect the page in intermediate state, the page lock + * is held. + */ + radix_tree_preload_end(); + if (!err) + return 0; + else if (err != -EEXIST) + goto failed_unlock; + + err = invalidate_inode_pages2_range(btnc, newkey, newkey); + if (!err) + goto retry; + /* fallback to copy mode */ + unlock_page(obh->b_page); + } + + nbh = nilfs_btnode_create_block(btnc, newkey); + if (!nbh) + return -ENOMEM; + + BUG_ON(nbh == obh); + ctxt->newbh = nbh; + return 0; + + failed_unlock: + unlock_page(obh->b_page); + return err; +} + +/** + * nilfs_btnode_commit_change_key + * commit the change_key operation prepared by prepare_change_key(). + */ +void nilfs_btnode_commit_change_key(struct address_space *btnc, + struct nilfs_btnode_chkey_ctxt *ctxt) +{ + struct buffer_head *obh = ctxt->bh, *nbh = ctxt->newbh; + __u64 oldkey = ctxt->oldkey, newkey = ctxt->newkey; + struct page *opage; + + if (oldkey == newkey) + return; + + if (nbh == NULL) { /* blocksize == pagesize */ + opage = obh->b_page; + if (unlikely(oldkey != opage->index)) + NILFS_PAGE_BUG(opage, + "invalid oldkey %lld (newkey=%lld)", + (unsigned long long)oldkey, + (unsigned long long)newkey); + mark_buffer_dirty(obh); + + spin_lock_irq(&btnc->tree_lock); + radix_tree_delete(&btnc->page_tree, oldkey); + radix_tree_tag_set(&btnc->page_tree, newkey, + PAGECACHE_TAG_DIRTY); + spin_unlock_irq(&btnc->tree_lock); + + opage->index = obh->b_blocknr = newkey; + unlock_page(opage); + } else { + nilfs_copy_buffer(nbh, obh); + mark_buffer_dirty(nbh); + + nbh->b_blocknr = newkey; + ctxt->bh = nbh; + nilfs_btnode_delete(obh); /* will decrement bh->b_count */ + } +} + +/** + * nilfs_btnode_abort_change_key + * abort the change_key operation prepared by prepare_change_key(). + */ +void nilfs_btnode_abort_change_key(struct address_space *btnc, + struct nilfs_btnode_chkey_ctxt *ctxt) +{ + struct buffer_head *nbh = ctxt->newbh; + __u64 oldkey = ctxt->oldkey, newkey = ctxt->newkey; + + if (oldkey == newkey) + return; + + if (nbh == NULL) { /* blocksize == pagesize */ + spin_lock_irq(&btnc->tree_lock); + radix_tree_delete(&btnc->page_tree, newkey); + spin_unlock_irq(&btnc->tree_lock); + unlock_page(ctxt->bh->b_page); + } else + brelse(nbh); +} -- cgit 1.2.3-korg