[Ocfs2-devel] [PATCH 06/30] ocfs2: Include do_sync_mapping_range() from mainline

[Mark Fasheh]

On Thu, Jan 03, 2008 at 11:19:42AM -0800, Sunil Mushran wrote:
> Commit 5b04aa3a64f854244bc40a6f528176ed50b5c4f6 introduced export symbol
> do_sync_mapping_range(). This patch allows one to build ocfs2 with kernels
> having/not having that change.
> 
> Signed-off-by: Sunil Mushran <sunil.mushran at oracle.com>
> Signed-off-by: Joel Becker <joel.becker at oracle.com>
> ---
>  Config.make.in                           |    2 +
>  Makefile                                 |    3 +-
>  configure.in                             |    6 ++
>  fs/ocfs2/Makefile                        |    4 +
>  kapi-compat/include/sync_mapping_range.h |  103 ++++++++++++++++++++++++++++++
>  5 files changed, 117 insertions(+), 1 deletions(-)
>  create mode 100644 kapi-compat/include/sync_mapping_range.h
> 
> diff --git a/Config.make.in b/Config.make.in
> index 1dc4d44..67ee363 100644
> --- a/Config.make.in
> +++ b/Config.make.in
> @@ -59,6 +59,8 @@ EXTRA_CFLAGS += @KAPI_COMPAT_CFLAGS@
>  
>  NO_DELAYED_WORK = @NO_DELAYED_WORK@
>  
> +NO_SYNC_MAPPING_RANGE  = @NO_SYNC_MAPPING_RANGE@
> +
>  OCFS_DEBUG = @OCFS_DEBUG@
>  
>  ifneq ($(OCFS_DEBUG),)
> diff --git a/Makefile b/Makefile
> index b7b86db..3ddb1aa 100644
> --- a/Makefile
> +++ b/Makefile
> @@ -11,7 +11,8 @@ LINUX_INCLUDE_FILES =
>  KAPI_COMPAT_FILES = \
>  	kapi-compat/include/workqueue.h \
>  	kapi-compat/include/compiler.h \
> -	kapi-compat/include/highmem.h
> +	kapi-compat/include/highmem.h \
> +	kapi-compat/include/sync_mapping_range.h
>  
>  PATCH_FILES =
>  
> diff --git a/configure.in b/configure.in
> index 0108f99..72698ae 100644
> --- a/configure.in
> +++ b/configure.in
> @@ -172,6 +172,12 @@ OCFS2_CHECK_KERNEL([zero_user_page() in highmem.h], highmem.h,
>    , highmem_compat_header="highmem.h", [zero_user_page])
>  KAPI_COMPAT_HEADERS="$KAPI_COMPAT_HEADERS $highmem_compat_header"
>  
> +NO_SYNC_MAPPING_RANGE=
> +OCFS2_CHECK_KERNEL([do_sync_mapping_range() in fs.h], fs.h,
> +  , NO_SYNC_MAPPING_RANGE=yes, [do_sync_mapping_range(])
> +KAPI_COMPAT_HEADERS="$KAPI_COMPAT_HEADERS sync_mapping_range.h"
> +AC_SUBST(NO_SYNC_MAPPING_RANGE)
> +
>  # using -include has two advantages:
>  #  the source doesn't need to know to include compat headers
>  #  the compat header file names don't go through the search path
> diff --git a/fs/ocfs2/Makefile b/fs/ocfs2/Makefile
> index 8bc2dff..737c12a 100644
> --- a/fs/ocfs2/Makefile
> +++ b/fs/ocfs2/Makefile
> @@ -29,6 +29,10 @@ ifdef NO_DELAYED_WORK
>  EXTRA_CFLAGS += -DNO_DELAYED_WORK
>  endif
>  
> +ifdef NO_SYNC_MAPPING_RANGE
> +CFLAGS_alloc.o += -DNO_SYNC_MAPPING_RANGE
> +endif
> +
>  #
>  # Since SUBDIRS means something to kbuild, define them safely.  Do not
>  # include trailing slashes.
> diff --git a/kapi-compat/include/sync_mapping_range.h b/kapi-compat/include/sync_mapping_range.h
> new file mode 100644
> index 0000000..d6e1b30
> --- /dev/null
> +++ b/kapi-compat/include/sync_mapping_range.h
> @@ -0,0 +1,103 @@
> +#ifndef KAPI_SYNC_MAPPING_RANGE_H
> +#define KAPI_SYNC_MAPPING_RANGE_H
> +
> +#ifdef NO_SYNC_MAPPING_RANGE
> +
> +#include <linux/fs.h>
> +#include <linux/types.h>
> +#include <linux/slab.h>
> +#include <linux/highmem.h>
> +#include <linux/swap.h>
> +#include <linux/writeback.h>
> +#include <linux/mpage.h>
> +#include <linux/pagemap.h>
> +
> +
> +int do_writepages(struct address_space *mapping, struct writeback_control *wbc)
> +{
> +	int ret;
> +
> +	if (wbc->nr_to_write <= 0)
> +		return 0;
> +	wbc->for_writepages = 1;
> +	if (mapping->a_ops->writepages)
> +		ret = mapping->a_ops->writepages(mapping, wbc);
> +	else
> +		ret = generic_writepages(mapping, wbc);
> +	wbc->for_writepages = 0;
> +	return ret;
> +}
> +
> +/**
> + * __filemap_fdatawrite_range - start writeback on mapping dirty pages in range
> + * @mapping:	address space structure to write
> + * @start:	offset in bytes where the range starts
> + * @end:	offset in bytes where the range ends (inclusive)
> + * @sync_mode:	enable synchronous operation
> + *
> + * Start writeback against all of a mapping's dirty pages that lie
> + * within the byte offsets <start, end> inclusive.
> + *
> + * If sync_mode is WB_SYNC_ALL then this is a "data integrity" operation, as
> + * opposed to a regular memory cleansing writeback.  The difference between
> + * these two operations is that if a dirty page/buffer is encountered, it must
> + * be waited upon, and not just skipped over.
> + */
> +int __filemap_fdatawrite_range(struct address_space *mapping, loff_t start,
> +				loff_t end, int sync_mode)
> +{
> +	int ret;
> +	struct writeback_control wbc = {
> +		.sync_mode = sync_mode,
> +		.nr_to_write = mapping->nrpages * 2,
> +		.range_start = start,
> +		.range_end = end,
> +	};
> +
> +	if (!mapping_cap_writeback_dirty(mapping))
> +		return 0;
> +
> +	ret = do_writepages(mapping, &wbc);
> +	return ret;
> +}
> +
> +/*
> + * `endbyte' is inclusive
> + */
> +static int do_sync_mapping_range(struct address_space *mapping, loff_t offset,
> +				 loff_t endbyte, unsigned int flags)
> +{
> +	int ret;
> +
> +	if (!mapping) {
> +		ret = -EINVAL;
> +		goto out;
> +	}
> +
> +	ret = 0;
> +	if (flags & SYNC_FILE_RANGE_WAIT_BEFORE) {
> +		ret = wait_on_page_writeback_range(mapping,
> +					offset >> PAGE_CACHE_SHIFT,
> +					endbyte >> PAGE_CACHE_SHIFT);
> +		if (ret < 0)
> +			goto out;
> +	}
> +
> +	if (flags & SYNC_FILE_RANGE_WRITE) {
> +		ret = __filemap_fdatawrite_range(mapping, offset, endbyte,
> +						WB_SYNC_NONE);
> +		if (ret < 0)
> +			goto out;
> +	}
> +
> +	if (flags & SYNC_FILE_RANGE_WAIT_AFTER) {
> +		ret = wait_on_page_writeback_range(mapping,
> +					offset >> PAGE_CACHE_SHIFT,
> +					endbyte >> PAGE_CACHE_SHIFT);
> +	}
> +out:
> +	return ret;
> +}

Shouldn't the function definitions be in a C file? It's pretty heavy for a
header....
	--Mark

--
Mark Fasheh
Principal Software Developer, Oracle
mark.fasheh at oracle.com