linux-stable-rt/fs/gfs2/lops.h

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/*
* Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved.
* Copyright (C) 2004-2008 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 __LOPS_DOT_H__
#define __LOPS_DOT_H__
#include <linux/list.h>
#include "incore.h"
[GFS2] assertion failure after writing to journaled file, umount This patch passes all my nasty tests that were causing the code to fail under one circumstance or another. Here is a complete summary of all changes from today's git tree, in order of appearance: 1. There are now separate variables for metadata buffer accounting. 2. Variable sd_log_num_hdrs is no longer needed, since the header accounting is taken care of by the reserve/refund sequence. 3. Fixed a tiny grammatical problem in a comment. 4. Added a new function "calc_reserved" to calculate the reserved log space. This isn't entirely necessary, but it has two benefits: First, it simplifies the gfs2_log_refund function greatly. Second, it allows for easier debugging because I could sprinkle the code with calls to this function to make sure the accounting is proper (by adding asserts and printks) at strategic point of the code. 5. In log_pull_tail there apparently was a kludge to fix up the accounting based on a "pull" parameter. The buffer accounting is now done properly, so the kludge was removed. 6. File sync operations were making a call to gfs2_log_flush that writes another journal header. Since that header was unplanned for (reserved) by the reserve/refund sequence, the free space had to be decremented so that when log_pull_tail gets called, the free space is be adjusted properly. (Did I hear you call that a kludge? well, maybe, but a lot more justifiable than the one I removed). 7. In the gfs2_log_shutdown code, it optionally syncs the log by specifying the PULL parameter to log_write_header. I'm not sure this is necessary anymore. It just seems to me there could be cases where shutdown is called while there are outstanding log buffers. 8. In the (data)buf_lo_before_commit functions, I changed some offset values from being calculated on the fly to being constants. That simplified some code and we might as well let the compiler do the calculation once rather than redoing those cycles at run time. 9. This version has my rewritten databuf_lo_add function. This version is much more like its predecessor, buf_lo_add, which makes it easier to understand. Again, this might not be necessary, but it seems as if this one works as well as the previous one, maybe even better, so I decided to leave it in. 10. In databuf_lo_before_commit, a previous data corruption problem was caused by going off the end of the buffer. The proper solution is to have the proper limit in place, rather than stopping earlier. (Thus my previous attempt to fix it is wrong). If you don't wrap the buffer, you're stopping too early and that causes more log buffer accounting problems. 11. In lops.h there are two new (previously mentioned) constants for figuring out the data offset for the journal buffers. 12. There are also two new functions, buf_limit and databuf_limit to calculate how many entries will fit in the buffer. 13. In function gfs2_meta_wipe, it needs to distinguish between pinned metadata buffers and journaled data buffers for proper journal buffer accounting. It can't use the JDATA gfs2_inode flag because it's sometimes passed the "real" inode and sometimes the "metadata inode" and the inode flags will be random bits in a metadata gfs2_inode. It needs to base its decision on which was passed in. Signed-off-by: Bob Peterson <rpeterso@redhat.com> Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2007-06-19 03:50:20 +08:00
#define BUF_OFFSET \
((sizeof(struct gfs2_log_descriptor) + sizeof(__be64) - 1) & \
~(sizeof(__be64) - 1))
#define DATABUF_OFFSET \
((sizeof(struct gfs2_log_descriptor) + (2 * sizeof(__be64) - 1)) & \
~(2 * sizeof(__be64) - 1))
extern const struct gfs2_log_operations gfs2_glock_lops;
extern const struct gfs2_log_operations gfs2_buf_lops;
extern const struct gfs2_log_operations gfs2_revoke_lops;
extern const struct gfs2_log_operations gfs2_rg_lops;
extern const struct gfs2_log_operations gfs2_databuf_lops;
extern const struct gfs2_log_operations *gfs2_log_ops[];
[GFS2] assertion failure after writing to journaled file, umount This patch passes all my nasty tests that were causing the code to fail under one circumstance or another. Here is a complete summary of all changes from today's git tree, in order of appearance: 1. There are now separate variables for metadata buffer accounting. 2. Variable sd_log_num_hdrs is no longer needed, since the header accounting is taken care of by the reserve/refund sequence. 3. Fixed a tiny grammatical problem in a comment. 4. Added a new function "calc_reserved" to calculate the reserved log space. This isn't entirely necessary, but it has two benefits: First, it simplifies the gfs2_log_refund function greatly. Second, it allows for easier debugging because I could sprinkle the code with calls to this function to make sure the accounting is proper (by adding asserts and printks) at strategic point of the code. 5. In log_pull_tail there apparently was a kludge to fix up the accounting based on a "pull" parameter. The buffer accounting is now done properly, so the kludge was removed. 6. File sync operations were making a call to gfs2_log_flush that writes another journal header. Since that header was unplanned for (reserved) by the reserve/refund sequence, the free space had to be decremented so that when log_pull_tail gets called, the free space is be adjusted properly. (Did I hear you call that a kludge? well, maybe, but a lot more justifiable than the one I removed). 7. In the gfs2_log_shutdown code, it optionally syncs the log by specifying the PULL parameter to log_write_header. I'm not sure this is necessary anymore. It just seems to me there could be cases where shutdown is called while there are outstanding log buffers. 8. In the (data)buf_lo_before_commit functions, I changed some offset values from being calculated on the fly to being constants. That simplified some code and we might as well let the compiler do the calculation once rather than redoing those cycles at run time. 9. This version has my rewritten databuf_lo_add function. This version is much more like its predecessor, buf_lo_add, which makes it easier to understand. Again, this might not be necessary, but it seems as if this one works as well as the previous one, maybe even better, so I decided to leave it in. 10. In databuf_lo_before_commit, a previous data corruption problem was caused by going off the end of the buffer. The proper solution is to have the proper limit in place, rather than stopping earlier. (Thus my previous attempt to fix it is wrong). If you don't wrap the buffer, you're stopping too early and that causes more log buffer accounting problems. 11. In lops.h there are two new (previously mentioned) constants for figuring out the data offset for the journal buffers. 12. There are also two new functions, buf_limit and databuf_limit to calculate how many entries will fit in the buffer. 13. In function gfs2_meta_wipe, it needs to distinguish between pinned metadata buffers and journaled data buffers for proper journal buffer accounting. It can't use the JDATA gfs2_inode flag because it's sometimes passed the "real" inode and sometimes the "metadata inode" and the inode flags will be random bits in a metadata gfs2_inode. It needs to base its decision on which was passed in. Signed-off-by: Bob Peterson <rpeterso@redhat.com> Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2007-06-19 03:50:20 +08:00
static inline unsigned int buf_limit(struct gfs2_sbd *sdp)
{
unsigned int limit;
limit = (sdp->sd_sb.sb_bsize - BUF_OFFSET) / sizeof(__be64);
return limit;
}
static inline unsigned int databuf_limit(struct gfs2_sbd *sdp)
{
unsigned int limit;
limit = (sdp->sd_sb.sb_bsize - DATABUF_OFFSET) / (2 * sizeof(__be64));
return limit;
}
static inline void lops_init_le(struct gfs2_log_element *le,
const struct gfs2_log_operations *lops)
{
INIT_LIST_HEAD(&le->le_list);
le->le_ops = lops;
}
static inline void lops_add(struct gfs2_sbd *sdp, struct gfs2_log_element *le)
{
if (le->le_ops->lo_add)
le->le_ops->lo_add(sdp, le);
}
static inline void lops_before_commit(struct gfs2_sbd *sdp)
{
int x;
for (x = 0; gfs2_log_ops[x]; x++)
if (gfs2_log_ops[x]->lo_before_commit)
gfs2_log_ops[x]->lo_before_commit(sdp);
}
static inline void lops_after_commit(struct gfs2_sbd *sdp, struct gfs2_ail *ai)
{
int x;
for (x = 0; gfs2_log_ops[x]; x++)
if (gfs2_log_ops[x]->lo_after_commit)
gfs2_log_ops[x]->lo_after_commit(sdp, ai);
}
static inline void lops_before_scan(struct gfs2_jdesc *jd,
struct gfs2_log_header_host *head,
unsigned int pass)
{
int x;
for (x = 0; gfs2_log_ops[x]; x++)
if (gfs2_log_ops[x]->lo_before_scan)
gfs2_log_ops[x]->lo_before_scan(jd, head, pass);
}
static inline int lops_scan_elements(struct gfs2_jdesc *jd, unsigned int start,
struct gfs2_log_descriptor *ld,
__be64 *ptr,
unsigned int pass)
{
int x, error;
for (x = 0; gfs2_log_ops[x]; x++)
if (gfs2_log_ops[x]->lo_scan_elements) {
error = gfs2_log_ops[x]->lo_scan_elements(jd, start,
ld, ptr, pass);
if (error)
return error;
}
return 0;
}
static inline void lops_after_scan(struct gfs2_jdesc *jd, int error,
unsigned int pass)
{
int x;
for (x = 0; gfs2_log_ops[x]; x++)
if (gfs2_log_ops[x]->lo_before_scan)
gfs2_log_ops[x]->lo_after_scan(jd, error, pass);
}
#endif /* __LOPS_DOT_H__ */