linux/fs/freevxfs/vxfs_subr.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

184 lines
4.6 KiB
C

/*
* Copyright (c) 2000-2001 Christoph Hellwig.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions, and the following disclaimer,
* without modification.
* 2. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* Alternatively, this software may be distributed under the terms of the
* GNU General Public License ("GPL").
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
* ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
/*
* Veritas filesystem driver - shared subroutines.
*/
#include <linux/fs.h>
#include <linux/buffer_head.h>
#include <linux/kernel.h>
#include <linux/pagemap.h>
#include "vxfs_extern.h"
static int vxfs_readpage(struct file *, struct page *);
static sector_t vxfs_bmap(struct address_space *, sector_t);
const struct address_space_operations vxfs_aops = {
.readpage = vxfs_readpage,
.bmap = vxfs_bmap,
.sync_page = block_sync_page,
};
inline void
vxfs_put_page(struct page *pp)
{
kunmap(pp);
page_cache_release(pp);
}
/**
* vxfs_get_page - read a page into memory.
* @ip: inode to read from
* @n: page number
*
* Description:
* vxfs_get_page reads the @n th page of @ip into the pagecache.
*
* Returns:
* The wanted page on success, else a NULL pointer.
*/
struct page *
vxfs_get_page(struct address_space *mapping, u_long n)
{
struct page * pp;
pp = read_mapping_page(mapping, n, NULL);
if (!IS_ERR(pp)) {
kmap(pp);
/** if (!PageChecked(pp)) **/
/** vxfs_check_page(pp); **/
if (PageError(pp))
goto fail;
}
return (pp);
fail:
vxfs_put_page(pp);
return ERR_PTR(-EIO);
}
/**
* vxfs_bread - read buffer for a give inode,block tuple
* @ip: inode
* @block: logical block
*
* Description:
* The vxfs_bread function reads block no @block of
* @ip into the buffercache.
*
* Returns:
* The resulting &struct buffer_head.
*/
struct buffer_head *
vxfs_bread(struct inode *ip, int block)
{
struct buffer_head *bp;
daddr_t pblock;
pblock = vxfs_bmap1(ip, block);
bp = sb_bread(ip->i_sb, pblock);
return (bp);
}
/**
* vxfs_get_block - locate buffer for given inode,block tuple
* @ip: inode
* @iblock: logical block
* @bp: buffer skeleton
* @create: %TRUE if blocks may be newly allocated.
*
* Description:
* The vxfs_get_block function fills @bp with the right physical
* block and device number to perform a lowlevel read/write on
* it.
*
* Returns:
* Zero on success, else a negativ error code (-EIO).
*/
static int
vxfs_getblk(struct inode *ip, sector_t iblock,
struct buffer_head *bp, int create)
{
daddr_t pblock;
pblock = vxfs_bmap1(ip, iblock);
if (pblock != 0) {
map_bh(bp, ip->i_sb, pblock);
return 0;
}
return -EIO;
}
/**
* vxfs_readpage - read one page synchronously into the pagecache
* @file: file context (unused)
* @page: page frame to fill in.
*
* Description:
* The vxfs_readpage routine reads @page synchronously into the
* pagecache.
*
* Returns:
* Zero on success, else a negative error code.
*
* Locking status:
* @page is locked and will be unlocked.
*/
static int
vxfs_readpage(struct file *file, struct page *page)
{
return block_read_full_page(page, vxfs_getblk);
}
/**
* vxfs_bmap - perform logical to physical block mapping
* @mapping: logical to physical mapping to use
* @block: logical block (relative to @mapping).
*
* Description:
* Vxfs_bmap find out the corresponding phsical block to the
* @mapping, @block pair.
*
* Returns:
* Physical block number on success, else Zero.
*
* Locking status:
* We are under the bkl.
*/
static sector_t
vxfs_bmap(struct address_space *mapping, sector_t block)
{
return generic_block_bmap(mapping, block, vxfs_getblk);
}