linux/fs/gfs2/meta_io.h
Bob Peterson 68942870c6 gfs2: Wipe jdata and ail1 in gfs2_journal_wipe, formerly gfs2_meta_wipe
Before this patch, when blocks were freed, it called gfs2_meta_wipe to
take the metadata out of the pending journal blocks. It did this mostly
by calling another function called gfs2_remove_from_journal. This is
shortsighted because it does not do anything with jdata blocks which
may also be in the journal.

This patch expands the function so that it wipes out jdata blocks from
the journal as well, and it wipes it from the ail1 list if it hasn't
been written back yet. Since it now processes jdata blocks as well,
the function has been renamed from gfs2_meta_wipe to gfs2_journal_wipe.

New function gfs2_ail1_wipe wants a static view of the ail list, so it
locks the sd_ail_lock when removing items. To accomplish this, function
gfs2_remove_from_journal no longer locks the sd_ail_lock, and it's now
the caller's responsibility to do so.

I was going to make sd_ail_lock locking conditional, but the practice is
generally frowned upon. For details, see: https://lwn.net/Articles/109066/

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2020-10-15 14:29:03 +02:00

79 lines
2.4 KiB
C

/* SPDX-License-Identifier: GPL-2.0-only */
/*
* Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved.
* Copyright (C) 2004-2006 Red Hat, Inc. All rights reserved.
*/
#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,
int rahead, 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);
enum {
REMOVE_JDATA = 0,
REMOVE_META = 1,
};
extern void gfs2_remove_from_journal(struct buffer_head *bh, int meta);
extern void gfs2_journal_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__ */