linux/fs/nilfs2/btnode.c
Tejun Heo 5a0e3ad6af include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h
percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files.  percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.

percpu.h -> slab.h dependency is about to be removed.  Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability.  As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.

  http://userweb.kernel.org/~tj/misc/slabh-sweep.py

The script does the followings.

* Scan files for gfp and slab usages and update includes such that
  only the necessary includes are there.  ie. if only gfp is used,
  gfp.h, if slab is used, slab.h.

* When the script inserts a new include, it looks at the include
  blocks and try to put the new include such that its order conforms
  to its surrounding.  It's put in the include block which contains
  core kernel includes, in the same order that the rest are ordered -
  alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
  doesn't seem to be any matching order.

* If the script can't find a place to put a new include (mostly
  because the file doesn't have fitting include block), it prints out
  an error message indicating which .h file needs to be added to the
  file.

The conversion was done in the following steps.

1. The initial automatic conversion of all .c files updated slightly
   over 4000 files, deleting around 700 includes and adding ~480 gfp.h
   and ~3000 slab.h inclusions.  The script emitted errors for ~400
   files.

2. Each error was manually checked.  Some didn't need the inclusion,
   some needed manual addition while adding it to implementation .h or
   embedding .c file was more appropriate for others.  This step added
   inclusions to around 150 files.

3. The script was run again and the output was compared to the edits
   from #2 to make sure no file was left behind.

4. Several build tests were done and a couple of problems were fixed.
   e.g. lib/decompress_*.c used malloc/free() wrappers around slab
   APIs requiring slab.h to be added manually.

5. The script was run on all .h files but without automatically
   editing them as sprinkling gfp.h and slab.h inclusions around .h
   files could easily lead to inclusion dependency hell.  Most gfp.h
   inclusion directives were ignored as stuff from gfp.h was usually
   wildly available and often used in preprocessor macros.  Each
   slab.h inclusion directive was examined and added manually as
   necessary.

6. percpu.h was updated not to include slab.h.

7. Build test were done on the following configurations and failures
   were fixed.  CONFIG_GCOV_KERNEL was turned off for all tests (as my
   distributed build env didn't work with gcov compiles) and a few
   more options had to be turned off depending on archs to make things
   build (like ipr on powerpc/64 which failed due to missing writeq).

   * x86 and x86_64 UP and SMP allmodconfig and a custom test config.
   * powerpc and powerpc64 SMP allmodconfig
   * sparc and sparc64 SMP allmodconfig
   * ia64 SMP allmodconfig
   * s390 SMP allmodconfig
   * alpha SMP allmodconfig
   * um on x86_64 SMP allmodconfig

8. percpu.h modifications were reverted so that it could be applied as
   a separate patch and serve as bisection point.

Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.

Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-30 22:02:32 +09:00

314 lines
8.2 KiB
C

/*
* 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 <kihara@osrg.net>
* and fully revised by Ryusuke Konishi <ryusuke@osrg.net> for
* stabilization and simplification.
*
*/
#include <linux/types.h>
#include <linux/buffer_head.h>
#include <linux/mm.h>
#include <linux/backing-dev.h>
#include <linux/gfp.h>
#include "nilfs.h"
#include "mdt.h"
#include "dat.h"
#include "page.h"
#include "btnode.h"
void nilfs_btnode_cache_init_once(struct address_space *btnc)
{
memset(btnc, 0, sizeof(*btnc));
INIT_RADIX_TREE(&btnc->page_tree, GFP_ATOMIC);
spin_lock_init(&btnc->tree_lock);
INIT_LIST_HEAD(&btnc->private_list);
spin_lock_init(&btnc->private_lock);
spin_lock_init(&btnc->i_mmap_lock);
INIT_RAW_PRIO_TREE_ROOT(&btnc->i_mmap);
INIT_LIST_HEAD(&btnc->i_mmap_nonlinear);
}
static const struct address_space_operations def_btnode_aops = {
.sync_page = block_sync_page,
};
void nilfs_btnode_cache_init(struct address_space *btnc,
struct backing_dev_info *bdi)
{
btnc->host = NULL; /* can safely set to host inode ? */
btnc->flags = 0;
mapping_set_gfp_mask(btnc, GFP_NOFS);
btnc->assoc_mapping = NULL;
btnc->backing_dev_info = bdi;
btnc->a_ops = &def_btnode_aops;
}
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 = NILFS_I_NILFS(inode)->ns_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, struct buffer_head **pbh)
{
struct buffer_head *bh;
struct inode *inode = NILFS_BTNC_I(btnc);
int err;
bh = nilfs_grab_buffer(inode, btnc, blocknr, 1 << BH_NILFS_Node);
if (unlikely(!bh))
return -ENOMEM;
err = -EEXIST; /* internal code */
if (buffer_uptodate(bh) || buffer_dirty(bh))
goto found;
if (pblocknr == 0) {
pblocknr = blocknr;
if (inode->i_ino != NILFS_DAT_INO) {
struct inode *dat =
nilfs_dat_inode(NILFS_I_NILFS(inode));
/* blocknr is a virtual block number */
err = nilfs_dat_translate(dat, blocknr, &pblocknr);
if (unlikely(err)) {
brelse(bh);
goto out_locked;
}
}
}
lock_buffer(bh);
if (buffer_uptodate(bh)) {
unlock_buffer(bh);
err = -EEXIST; /* internal code */
goto found;
}
set_buffer_mapped(bh);
bh->b_bdev = NILFS_I_NILFS(inode)->ns_bdev;
bh->b_blocknr = pblocknr; /* set block address for read */
bh->b_end_io = end_buffer_read_sync;
get_bh(bh);
submit_bh(READ, bh);
bh->b_blocknr = blocknr; /* set back to the given block address */
err = 0;
found:
*pbh = bh;
out_locked:
unlock_page(bh->b_page);
page_cache_release(bh->b_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);
nilfs_btnode_mark_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);
nilfs_btnode_mark_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);
}