1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
|
/*
* Copyright (c) 2013 Jie Liu.
* 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
*/
#include "xfs.h"
#include "xfs_fs.h"
#include "xfs_shared.h"
#include "xfs_log.h"
#include "xfs_trans.h"
#include "xfs_ag.h"
#include "xfs_sb.h"
#include "xfs_mount.h"
#include "xfs_trans_space.h"
#include "xfs_bmap_btree.h"
#include "xfs_inode.h"
#include "xfs_da_btree.h"
#include "xfs_attr_leaf.h"
/*
* Calculate the maximum length in bytes that would be required for a local
* attribute value as large attributes out of line are not logged.
*/
STATIC int
xfs_log_calc_max_attrsetm_res(
struct xfs_mount *mp)
{
int size;
int nblks;
size = xfs_attr_leaf_entsize_local_max(mp->m_sb.sb_blocksize) -
MAXNAMELEN - 1;
nblks = XFS_DAENTER_SPACE_RES(mp, XFS_ATTR_FORK);
nblks += XFS_B_TO_FSB(mp, size);
nblks += XFS_NEXTENTADD_SPACE_RES(mp, size, XFS_ATTR_FORK);
return M_RES(mp)->tr_attrsetm.tr_logres +
M_RES(mp)->tr_attrsetrt.tr_logres * nblks;
}
/*
* Iterate over the log space reservation table to figure out and return
* the maximum one in terms of the pre-calculated values which were done
* at mount time.
*/
STATIC void
xfs_log_get_max_trans_res(
struct xfs_mount *mp,
struct xfs_trans_res *max_resp)
{
struct xfs_trans_res *resp;
struct xfs_trans_res *end_resp;
int log_space = 0;
int attr_space;
attr_space = xfs_log_calc_max_attrsetm_res(mp);
resp = (struct xfs_trans_res *)M_RES(mp);
end_resp = (struct xfs_trans_res *)(M_RES(mp) + 1);
for (; resp < end_resp; resp++) {
int tmp = resp->tr_logcount > 1 ?
resp->tr_logres * resp->tr_logcount :
resp->tr_logres;
if (log_space < tmp) {
log_space = tmp;
*max_resp = *resp; /* struct copy */
}
}
if (attr_space > log_space) {
*max_resp = M_RES(mp)->tr_attrsetm; /* struct copy */
max_resp->tr_logres = attr_space;
}
}
/*
* Calculate the minimum valid log size for the given superblock configuration.
* Used to calculate the minimum log size at mkfs time, and to determine if
* the log is large enough or not at mount time. Returns the minimum size in
* filesystem block size units.
*/
int
xfs_log_calc_minimum_size(
struct xfs_mount *mp)
{
struct xfs_trans_res tres = {0};
int max_logres;
int min_logblks = 0;
int lsunit = 0;
xfs_log_get_max_trans_res(mp, &tres);
max_logres = xfs_log_calc_unit_res(mp, tres.tr_logres);
if (tres.tr_logcount > 1)
max_logres *= tres.tr_logcount;
if (xfs_sb_version_haslogv2(&mp->m_sb) && mp->m_sb.sb_logsunit > 1)
lsunit = BTOBB(mp->m_sb.sb_logsunit);
/*
* Two factors should be taken into account for calculating the minimum
* log space.
* 1) The fundamental limitation is that no single transaction can be
* larger than half size of the log.
*
* From mkfs.xfs, this is considered by the XFS_MIN_LOG_FACTOR
* define, which is set to 3. That means we can definitely fit
* maximally sized 2 transactions in the log. We'll use this same
* value here.
*
* 2) If the lsunit option is specified, a transaction requires 2 LSU
* for the reservation because there are two log writes that can
* require padding - the transaction data and the commit record which
* are written separately and both can require padding to the LSU.
* Consider that we can have an active CIL reservation holding 2*LSU,
* but the CIL is not over a push threshold, in this case, if we
* don't have enough log space for at one new transaction, which
* includes another 2*LSU in the reservation, we will run into dead
* loop situation in log space grant procedure. i.e.
* xlog_grant_head_wait().
*
* Hence the log size needs to be able to contain two maximally sized
* and padded transactions, which is (2 * (2 * LSU + maxlres)).
*
* Also, the log size should be a multiple of the log stripe unit, round
* it up to lsunit boundary if lsunit is specified.
*/
if (lsunit) {
min_logblks = roundup_64(BTOBB(max_logres), lsunit) +
2 * lsunit;
} else
min_logblks = BTOBB(max_logres) + 2 * BBSIZE;
min_logblks *= XFS_MIN_LOG_FACTOR;
return XFS_BB_TO_FSB(mp, min_logblks);
}
|
