[PATCH 22/28] xfs: use generic get_unaligned_beXX helpers

Christoph Hellwig
2011-07-07T11:06:46Z

[-- Attachment #1: xfs-dir2-use-generic-unaligned-byteswap-macros --]
[-- Type: text/plain, Size: 7602 bytes --]

Switch the shortform directory code over to use the generic
get_unaligned_beXX helpers instead of reinventing them. As a result
kill off xfs_arch.h and move the setting of XFS_NATIVE_HOST into
xfs_linux.h.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Alex Elder <aelder@sgi.com>

Index: xfs/fs/xfs/linux-2.6/xfs_linux.h
===================================================================
--- xfs.orig/fs/xfs/linux-2.6/xfs_linux.h 2011-06-30 20:22:44.849587371 +0200
+++ xfs/fs/xfs/linux-2.6/xfs_linux.h 2011-06-30 20:40:52.116240531 +0200
@@ -33,7 +33,6 @@
#endif

#include <xfs_types.h>
-#include <xfs_arch.h>

#include <kmem.h>
#include <mrlock.h>
@@ -88,6 +87,12 @@
#include <xfs_buf.h>
#include <xfs_message.h>

+#ifdef __BIG_ENDIAN
+#define XFS_NATIVE_HOST 1
+#else
+#undef XFS_NATIVE_HOST
+#endif
+
/*
* Feature macros (disable/enable)
*/
Index: xfs/fs/xfs/xfs_arch.h
===================================================================
--- xfs.orig/fs/xfs/xfs_arch.h 2011-06-30 20:21:42.116254819 +0200
+++ /dev/null 1970-01-01 00:00:00.000000000 +0000
@@ -1,136 +0,0 @@
-/*
- * Copyright (c) 2000-2002,2005 Silicon Graphics, Inc.
- * All Rights Reserved.
- *
- * 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.
- *
- * This program is distributed in the hope that it would 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 the Free Software Foundation,
- * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
- */
-#ifndef __XFS_ARCH_H__
-#define __XFS_ARCH_H__
-
-#ifndef XFS_BIG_INUMS
-# error XFS_BIG_INUMS must be defined true or false
-#endif
-
-#ifdef __KERNEL__
-
-#include <asm/byteorder.h>
-
-#ifdef __BIG_ENDIAN
-#define XFS_NATIVE_HOST 1
-#else
-#undef XFS_NATIVE_HOST
-#endif
-
-#else /* __KERNEL__ */
-
-#if __BYTE_ORDER == __BIG_ENDIAN
-#define XFS_NATIVE_HOST 1
-#else
-#undef XFS_NATIVE_HOST
-#endif
-
-#ifdef XFS_NATIVE_HOST
-#define cpu_to_be16(val) ((__force __be16)(__u16)(val))
-#define cpu_to_be32(val) ((__force __be32)(__u32)(val))
-#define cpu_to_be64(val) ((__force __be64)(__u64)(val))
-#define be16_to_cpu(val) ((__force __u16)(__be16)(val))
-#define be32_to_cpu(val) ((__force __u32)(__be32)(val))
-#define be64_to_cpu(val) ((__force __u64)(__be64)(val))
-#else
-#define cpu_to_be16(val) ((__force __be16)__swab16((__u16)(val)))
-#define cpu_to_be32(val) ((__force __be32)__swab32((__u32)(val)))
-#define cpu_to_be64(val) ((__force __be64)__swab64((__u64)(val)))
-#define be16_to_cpu(val) (__swab16((__force __u16)(__be16)(val)))
-#define be32_to_cpu(val) (__swab32((__force __u32)(__be32)(val)))
-#define be64_to_cpu(val) (__swab64((__force __u64)(__be64)(val)))
-#endif
-
-static inline void be16_add_cpu(__be16 *a, __s16 b)
-{
- *a = cpu_to_be16(be16_to_cpu(*a) + b);
-}
-
-static inline void be32_add_cpu(__be32 *a, __s32 b)
-{
- *a = cpu_to_be32(be32_to_cpu(*a) + b);
-}
-
-static inline void be64_add_cpu(__be64 *a, __s64 b)
-{
- *a = cpu_to_be64(be64_to_cpu(*a) + b);
-}
-
-#endif /* __KERNEL__ */
-
-/*
- * get and set integers from potentially unaligned locations
- */
-
-#define INT_GET_UNALIGNED_16_BE(pointer) \
- ((__u16)((((__u8*)(pointer))[0] << 8) | (((__u8*)(pointer))[1])))
-#define INT_SET_UNALIGNED_16_BE(pointer,value) \
- { \
- ((__u8*)(pointer))[0] = (((value) >> 8) & 0xff); \
- ((__u8*)(pointer))[1] = (((value) ) & 0xff); \
- }
-
-/*
- * In directories inode numbers are stored as unaligned arrays of unsigned
- * 8bit integers on disk.
- *
- * For v1 directories or v2 directories that contain inode numbers that
- * do not fit into 32bit the array has eight members, but the first member
- * is always zero:
- *
- * |unused|48-55|40-47|32-39|24-31|16-23| 8-15| 0- 7|
- *
- * For v2 directories that only contain entries with inode numbers that fit
- * into 32bits a four-member array is used:
- *
- * |24-31|16-23| 8-15| 0- 7|
- */
-
-#define XFS_GET_DIR_INO4(di) \
- (((__u32)(di).i[0] << 24) | ((di).i[1] << 16) | ((di).i[2] << 8) | ((di).i[3]))
-
-#define XFS_PUT_DIR_INO4(from, di) \
-do { \
- (di).i[0] = (((from) & 0xff000000ULL) >> 24); \
- (di).i[1] = (((from) & 0x00ff0000ULL) >> 16); \
- (di).i[2] = (((from) & 0x0000ff00ULL) >> 8); \
- (di).i[3] = ((from) & 0x000000ffULL); \
-} while (0)
-
-#define XFS_DI_HI(di) \
- (((__u32)(di).i[1] << 16) | ((di).i[2] << 8) | ((di).i[3]))
-#define XFS_DI_LO(di) \
- (((__u32)(di).i[4] << 24) | ((di).i[5] << 16) | ((di).i[6] << 8) | ((di).i[7]))
-
-#define XFS_GET_DIR_INO8(di) \
- (((xfs_ino_t)XFS_DI_LO(di) & 0xffffffffULL) | \
- ((xfs_ino_t)XFS_DI_HI(di) << 32))
-
-#define XFS_PUT_DIR_INO8(from, di) \
-do { \
- (di).i[0] = 0; \
- (di).i[1] = (((from) & 0x00ff000000000000ULL) >> 48); \
- (di).i[2] = (((from) & 0x0000ff0000000000ULL) >> 40); \
- (di).i[3] = (((from) & 0x000000ff00000000ULL) >> 32); \
- (di).i[4] = (((from) & 0x00000000ff000000ULL) >> 24); \
- (di).i[5] = (((from) & 0x0000000000ff0000ULL) >> 16); \
- (di).i[6] = (((from) & 0x000000000000ff00ULL) >> 8); \
- (di).i[7] = ((from) & 0x00000000000000ffULL); \
-} while (0)
-
-#endif /* __XFS_ARCH_H__ */
Index: xfs/fs/xfs/xfs_dir2_sf.c
===================================================================
--- xfs.orig/fs/xfs/xfs_dir2_sf.c 2011-06-30 20:24:26.516252776 +0200
+++ xfs/fs/xfs/xfs_dir2_sf.c 2011-06-30 20:46:45.366236141 +0200
@@ -59,11 +59,12 @@ static void xfs_dir2_sf_toino4(xfs_da_ar
static void xfs_dir2_sf_toino8(xfs_da_args_t *args);
#endif /* XFS_BIG_INUMS */

-
/*
* Inode numbers in short-form directories can come in two versions,
* either 4 bytes or 8 bytes wide. These helpers deal with the
* two forms transparently by looking at the headers i8count field.
+ *
+ * For 64-bit inode number the most significant byte must be zero.
*/
static xfs_ino_t
xfs_dir2_sf_get_ino(
@@ -71,9 +72,9 @@ xfs_dir2_sf_get_ino(
xfs_dir2_inou_t *from)
{
if (hdr->i8count)
- return XFS_GET_DIR_INO8(from->i8);
+ return get_unaligned_be64(&from->i8.i) & 0x00ffffffffffffffULL;
else
- return XFS_GET_DIR_INO4(from->i4);
+ return get_unaligned_be32(&from->i4.i);
}

static void
@@ -82,10 +83,12 @@ xfs_dir2_sf_put_ino(
xfs_dir2_inou_t *to,
xfs_ino_t ino)
{
+ ASSERT((ino & 0xff00000000000000ULL) == 0);
+
if (hdr->i8count)
- XFS_PUT_DIR_INO8(ino, to->i8);
+ put_unaligned_be64(ino, &to->i8.i);
else
- XFS_PUT_DIR_INO4(ino, to->i4);
+ put_unaligned_be32(ino, &to->i4.i);
}

xfs_ino_t
Index: xfs/fs/xfs/xfs_dir2_sf.h
===================================================================
--- xfs.orig/fs/xfs/xfs_dir2_sf.h 2011-06-30 20:24:08.732919663 +0200
+++ xfs/fs/xfs/xfs_dir2_sf.h 2011-06-30 20:38:37.019575543 +0200
@@ -95,13 +95,13 @@ static inline int xfs_dir2_sf_hdr_size(i
static inline xfs_dir2_data_aoff_t
xfs_dir2_sf_get_offset(xfs_dir2_sf_entry_t *sfep)
{
- return INT_GET_UNALIGNED_16_BE(&(sfep)->offset.i);
+ return get_unaligned_be16(&sfep->offset.i);
}

static inline void
xfs_dir2_sf_put_offset(xfs_dir2_sf_entry_t *sfep, xfs_dir2_data_aoff_t off)
{
- INT_SET_UNALIGNED_16_BE(&(sfep)->offset.i, off);
+ put_unaligned_be16(off, &sfep->offset.i);
}

static inline int