[Ocfs2-devel] [PATCH 27/30] ocfs2: Handle missing vectorized fileops aio_read() and aio_write()

[Mark Fasheh <mark.fasheh@oracle.com>]

On Thu, Jan 03, 2008 at 11:20:03AM -0800, Sunil Mushran wrote:
> Commit 027445c37282bc1ed26add45e573ad2d3e4860a5 in mainline vectorized
> fileops aio_read() and aio_write(). This patch allows one to build ocfs2
> with kernels having/not having this change.
> 
> Signed-off-by: Sunil Mushran <sunil.mushran@oracle.com>
> Signed-off-by: Joel Becker <joel.becker@oracle.com>
> ---
>  Config.make.in               |    1 +
>  Makefile                     |    3 +-
>  configure.in                 |    6 ++++
>  fs/ocfs2/Makefile            |    4 ++
>  fs/ocfs2/file.c              |    6 ++--
>  kapi-compat/include/aiovec.h |   68 ++++++++++++++++++++++++++++++++++++++++++
>  6 files changed, 84 insertions(+), 4 deletions(-)
>  create mode 100644 kapi-compat/include/aiovec.h
> 
> diff --git a/Config.make.in b/Config.make.in
> index 4b2d1c5..c6deb57 100644
> --- a/Config.make.in
> +++ b/Config.make.in
> @@ -72,6 +72,7 @@ NO_SHOULD_REMOVE_SUID = @NO_SHOULD_REMOVE_SUID@
>  NO_GENERIC_SEGMENT_CHECKS = @NO_GENERIC_SEGMENT_CHECKS@
>  SOP_IS_NOT_CONST = @SOP_IS_NOT_CONST@
>  IOP_IS_NOT_CONST = @IOP_IS_NOT_CONST@
> +NO_VECTORIZED_AIO = @NO_VECTORIZED_AIO@
>  
>  OCFS_DEBUG = @OCFS_DEBUG@
>  
> diff --git a/Makefile b/Makefile
> index 9427ce6..a3a0c9d 100644
> --- a/Makefile
> +++ b/Makefile
> @@ -27,7 +27,8 @@ KAPI_COMPAT_FILES = \
>  	kapi-compat/include/cap.h \
>  	kapi-compat/include/relatime.h \
>  	kapi-compat/include/should_remove_suid.h \
> -	kapi-compat/include/generic_segment_checks.h
> +	kapi-compat/include/generic_segment_checks.h \
> +	kapi-compat/include/aiovec.h
>  
>  PATCH_FILES =
>  
> diff --git a/configure.in b/configure.in
> index a6f4336..8c30910 100644
> --- a/configure.in
> +++ b/configure.in
> @@ -285,6 +285,12 @@ OCFS2_CHECK_KERNEL([i_op declared as const in struct inode in fs.h], fs.h,
>    , IOP_IS_NOT_CONST=yes, [^.*const struct inode_operations.*\*i_op;])
>  AC_SUBST(IOP_IS_NOT_CONST)
>  
> +NO_VECTORIZED_AIO=
> +OCFS2_CHECK_KERNEL([aio_read() in struct file_operations using iovec in fs.h], fs.h,
> +  , NO_VECTORIZED_AIO=yes, [ssize_t (\*aio_read) (struct kiocb \*, const struct iovec \*, unsigned long, loff_t);])
> +AC_SUBST(NO_VECTORIZED_AIO)
> +KAPI_COMPAT_HEADERS="$KAPI_COMPAT_HEADERS aiovec.h"
> +
>  # 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 a894c45..1646a9b 100644
> --- a/fs/ocfs2/Makefile
> +++ b/fs/ocfs2/Makefile
> @@ -73,6 +73,10 @@ ifdef IOP_IS_NOT_CONST
>  EXTRA_CFLAGS += -DIOP_IS_NOT_CONST
>  endif
>  
> +ifdef NO_VECTORIZED_AIO
> +CFLAGS_file.o += -DNO_VECTORIZED_AIO
> +endif
> +
>  #
>  # Since SUBDIRS means something to kbuild, define them safely.  Do not
>  # include trailing slashes.
> diff --git a/fs/ocfs2/file.c b/fs/ocfs2/file.c
> index a19322e..62040aa 100644
> --- a/fs/ocfs2/file.c
> +++ b/fs/ocfs2/file.c
> @@ -2017,7 +2017,7 @@ out:
>  	return total ? total : ret;
>  }
>  
> -static ssize_t ocfs2_file_aio_write(struct kiocb *iocb,
> +static ssize_t __ocfs2_file_aio_write(struct kiocb *iocb,
>  				    const struct iovec *iov,
>  				    unsigned long nr_segs,
>  				    loff_t pos)
> @@ -2322,7 +2322,7 @@ bail:
>  	return ret;
>  }
>  
> -static ssize_t ocfs2_file_aio_read(struct kiocb *iocb,
> +static ssize_t __ocfs2_file_aio_read(struct kiocb *iocb,
>  				   const struct iovec *iov,
>  				   unsigned long nr_segs,
>  				   loff_t pos)
> @@ -2376,7 +2376,7 @@ static ssize_t ocfs2_file_aio_read(struct kiocb *iocb,
>  	}
>  	ocfs2_meta_unlock(inode, lock_level);
>  
> -	ret = generic_file_aio_read(iocb, iov, nr_segs, iocb->ki_pos);
> +	ret = kapi_generic_file_aio_read(iocb, iov, nr_segs, iocb->ki_pos);
>  	if (ret == -EINVAL)
>  		mlog(ML_ERROR, "generic_file_aio_read returned -EINVAL\n");
>  
> diff --git a/kapi-compat/include/aiovec.h b/kapi-compat/include/aiovec.h
> new file mode 100644
> index 0000000..e6cb3fb
> --- /dev/null
> +++ b/kapi-compat/include/aiovec.h
> @@ -0,0 +1,68 @@
> +#ifndef KAPI_AIOVEC_H
> +#define KAPI_AIOVEC_H
> +
> +#ifdef NO_VECTORIZED_AIO
> +
> +#include <linux/fs.h>
> +#include <linux/uio.h>
> +
> +static ssize_t kapi_generic_file_aio_read(struct kiocb *iocb,
> +					  const struct iovec *iov,
> +					  unsigned long nr_segs,
> +					  loff_t pos)
> +{
> +	BUG_ON(nr_segs != 1);
> +	return generic_file_aio_read(iocb, iov->iov_base, iov->iov_len, pos);
> +}
> +
> +static ssize_t __ocfs2_file_aio_read(struct kiocb *iocb,
> +				     const struct iovec *iov,
> +				     unsigned long nr_segs,
> +				     loff_t pos);
> +
> +static ssize_t ocfs2_file_aio_read(struct kiocb *iocb,
> +				   char __user *buf,
> +				   size_t buflen,
> +				   loff_t pos)
> +{
> +	struct iovec iov_local = { .iov_base = (void __user *)buf,
> +				   .iov_len  = buflen };
> +	const struct iovec *iov = &iov_local;
> +	unsigned long nr_segs = 1;
> +
> +	return __ocfs2_file_aio_read(iocb, iov, nr_segs, pos);
> +}
> +
> +static ssize_t __ocfs2_file_aio_write(struct kiocb *iocb,
> +				      const struct iovec *iov,
> +				      unsigned long nr_segs,
> +				      loff_t pos);
> +
> +static ssize_t ocfs2_file_aio_write(struct kiocb *iocb,
> +				    const char __user *buf,
> +				    size_t buflen,
> +				    loff_t pos)
> +{
> +	struct iovec iov_local = { .iov_base = (void __user *)buf,
> +				   .iov_len  = buflen };
> +	const struct iovec *iov = &iov_local;
> +	unsigned long nr_segs = 1;
> +
> +	iocb->ki_left = buflen;
> +	return __ocfs2_file_aio_write(iocb, iov, nr_segs, pos);
> +}
> +
> +#else	/* ! NO_VECTORIZED_AIO */
> +
> +#define kapi_generic_file_aio_read(a, b, c, d) \
> +			generic_file_aio_read(a, b, c, d)
> +
> +#define ocfs2_file_aio_read(a, b, c, d) \
> +			__ocfs2_file_aio_read(a, b, c, d)
> +
> +#define ocfs2_file_aio_write(a, b, c, d) \
> +			__ocfs2_file_aio_write(a, b, c, d)

ocfs2_file_aio_read and ocfs2_file_aio_write are pointed to by the
operations struct. Does this still compile and work against a 2.6.24 kernel?
	--Mark

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