linux/fs/gfs2/meta_io.h
Bob Peterson 15562c439d GFS2: Move glock superblock pointer to field gl_name
What uniquely identifies a glock in the glock hash table is not
gl_name, but gl_name and its superblock pointer. This patch makes
the gl_name field correspond to a unique glock identifier. That will
allow us to simplify hashing with a future patch, since the hash
algorithm can then take the gl_name and hash its components in one
operation.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Acked-by: Steven Whitehouse <swhiteho@redhat.com>
2015-09-03 13:33:09 -05:00

79 lines
2.5 KiB
C

/*
* Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved.
* Copyright (C) 2004-2006 Red Hat, Inc. All rights reserved.
*
* This copyrighted material is made available to anyone wishing to use,
* modify, copy, or redistribute it subject to the terms and conditions
* of the GNU General Public License version 2.
*/
#ifndef __DIO_DOT_H__
#define __DIO_DOT_H__
#include <linux/buffer_head.h>
#include <linux/string.h>
#include "incore.h"
static inline void gfs2_buffer_clear(struct buffer_head *bh)
{
memset(bh->b_data, 0, bh->b_size);
}
static inline void gfs2_buffer_clear_tail(struct buffer_head *bh, int head)
{
BUG_ON(head > bh->b_size);
memset(bh->b_data + head, 0, bh->b_size - head);
}
static inline void gfs2_buffer_copy_tail(struct buffer_head *to_bh,
int to_head,
struct buffer_head *from_bh,
int from_head)
{
BUG_ON(from_head < to_head);
memcpy(to_bh->b_data + to_head, from_bh->b_data + from_head,
from_bh->b_size - from_head);
memset(to_bh->b_data + to_bh->b_size + to_head - from_head,
0, from_head - to_head);
}
extern const struct address_space_operations gfs2_meta_aops;
extern const struct address_space_operations gfs2_rgrp_aops;
static inline struct gfs2_sbd *gfs2_mapping2sbd(struct address_space *mapping)
{
struct inode *inode = mapping->host;
if (mapping->a_ops == &gfs2_meta_aops)
return (((struct gfs2_glock *)mapping) - 1)->gl_name.ln_sbd;
else if (mapping->a_ops == &gfs2_rgrp_aops)
return container_of(mapping, struct gfs2_sbd, sd_aspace);
else
return inode->i_sb->s_fs_info;
}
extern struct buffer_head *gfs2_meta_new(struct gfs2_glock *gl, u64 blkno);
extern int gfs2_meta_read(struct gfs2_glock *gl, u64 blkno, int flags,
struct buffer_head **bhp);
extern int gfs2_meta_wait(struct gfs2_sbd *sdp, struct buffer_head *bh);
extern struct buffer_head *gfs2_getbuf(struct gfs2_glock *gl, u64 blkno,
int create);
extern void gfs2_remove_from_journal(struct buffer_head *bh,
struct gfs2_trans *tr, int meta);
extern void gfs2_meta_wipe(struct gfs2_inode *ip, u64 bstart, u32 blen);
extern int gfs2_meta_indirect_buffer(struct gfs2_inode *ip, int height, u64 num,
struct buffer_head **bhp);
static inline int gfs2_meta_inode_buffer(struct gfs2_inode *ip,
struct buffer_head **bhp)
{
return gfs2_meta_indirect_buffer(ip, 0, ip->i_no_addr, bhp);
}
struct buffer_head *gfs2_meta_ra(struct gfs2_glock *gl, u64 dblock, u32 extlen);
#define buffer_busy(bh) \
((bh)->b_state & ((1ul << BH_Dirty) | (1ul << BH_Lock) | (1ul << BH_Pinned)))
#endif /* __DIO_DOT_H__ */