Merge git://git.kernel.org/pub/scm/linux/kernel/git/steve/gfs2-2.6-nmw
[pandora-kernel.git] / fs / gfs2 / trans.c
1 /*
2  * Copyright (C) Sistina Software, Inc.  1997-2003 All rights reserved.
3  * Copyright (C) 2004-2006 Red Hat, Inc.  All rights reserved.
4  *
5  * This copyrighted material is made available to anyone wishing to use,
6  * modify, copy, or redistribute it subject to the terms and conditions
7  * of the GNU General Public License version 2.
8  */
9
10 #include <linux/sched.h>
11 #include <linux/slab.h>
12 #include <linux/spinlock.h>
13 #include <linux/completion.h>
14 #include <linux/buffer_head.h>
15 #include <linux/kallsyms.h>
16 #include <linux/gfs2_ondisk.h>
17
18 #include "gfs2.h"
19 #include "incore.h"
20 #include "glock.h"
21 #include "log.h"
22 #include "lops.h"
23 #include "meta_io.h"
24 #include "trans.h"
25 #include "util.h"
26 #include "trace_gfs2.h"
27
28 int gfs2_trans_begin(struct gfs2_sbd *sdp, unsigned int blocks,
29                      unsigned int revokes)
30 {
31         struct gfs2_trans *tr;
32         int error;
33
34         BUG_ON(current->journal_info);
35         BUG_ON(blocks == 0 && revokes == 0);
36
37         if (!test_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags))
38                 return -EROFS;
39
40         tr = kzalloc(sizeof(struct gfs2_trans), GFP_NOFS);
41         if (!tr)
42                 return -ENOMEM;
43
44         tr->tr_ip = (unsigned long)__builtin_return_address(0);
45         tr->tr_blocks = blocks;
46         tr->tr_revokes = revokes;
47         tr->tr_reserved = 1;
48         if (blocks)
49                 tr->tr_reserved += 6 + blocks;
50         if (revokes)
51                 tr->tr_reserved += gfs2_struct2blk(sdp, revokes,
52                                                    sizeof(u64));
53         INIT_LIST_HEAD(&tr->tr_list_buf);
54
55         gfs2_holder_init(sdp->sd_trans_gl, LM_ST_SHARED, 0, &tr->tr_t_gh);
56
57         error = gfs2_glock_nq(&tr->tr_t_gh);
58         if (error)
59                 goto fail_holder_uninit;
60
61         error = gfs2_log_reserve(sdp, tr->tr_reserved);
62         if (error)
63                 goto fail_gunlock;
64
65         current->journal_info = tr;
66
67         return 0;
68
69 fail_gunlock:
70         gfs2_glock_dq(&tr->tr_t_gh);
71
72 fail_holder_uninit:
73         gfs2_holder_uninit(&tr->tr_t_gh);
74         kfree(tr);
75
76         return error;
77 }
78
79 /**
80  * gfs2_log_release - Release a given number of log blocks
81  * @sdp: The GFS2 superblock
82  * @blks: The number of blocks
83  *
84  */
85
86 static void gfs2_log_release(struct gfs2_sbd *sdp, unsigned int blks)
87 {
88
89         atomic_add(blks, &sdp->sd_log_blks_free);
90         trace_gfs2_log_blocks(sdp, blks);
91         gfs2_assert_withdraw(sdp, atomic_read(&sdp->sd_log_blks_free) <=
92                                   sdp->sd_jdesc->jd_blocks);
93         up_read(&sdp->sd_log_flush_lock);
94 }
95
96 void gfs2_trans_end(struct gfs2_sbd *sdp)
97 {
98         struct gfs2_trans *tr = current->journal_info;
99
100         BUG_ON(!tr);
101         current->journal_info = NULL;
102
103         if (!tr->tr_touched) {
104                 gfs2_log_release(sdp, tr->tr_reserved);
105                 if (tr->tr_t_gh.gh_gl) {
106                         gfs2_glock_dq(&tr->tr_t_gh);
107                         gfs2_holder_uninit(&tr->tr_t_gh);
108                         kfree(tr);
109                 }
110                 return;
111         }
112
113         if (gfs2_assert_withdraw(sdp, tr->tr_num_buf <= tr->tr_blocks)) {
114                 fs_err(sdp, "tr_num_buf = %u, tr_blocks = %u ",
115                        tr->tr_num_buf, tr->tr_blocks);
116                 print_symbol(KERN_WARNING "GFS2: Transaction created at: %s\n", tr->tr_ip);
117         }
118         if (gfs2_assert_withdraw(sdp, tr->tr_num_revoke <= tr->tr_revokes)) {
119                 fs_err(sdp, "tr_num_revoke = %u, tr_revokes = %u ",
120                        tr->tr_num_revoke, tr->tr_revokes);
121                 print_symbol(KERN_WARNING "GFS2: Transaction created at: %s\n", tr->tr_ip);
122         }
123
124         gfs2_log_commit(sdp, tr);
125         if (tr->tr_t_gh.gh_gl) {
126                 gfs2_glock_dq(&tr->tr_t_gh);
127                 gfs2_holder_uninit(&tr->tr_t_gh);
128                 kfree(tr);
129         }
130
131         if (sdp->sd_vfs->s_flags & MS_SYNCHRONOUS)
132                 gfs2_log_flush(sdp, NULL);
133 }
134
135 /**
136  * gfs2_trans_add_bh - Add a to-be-modified buffer to the current transaction
137  * @gl: the glock the buffer belongs to
138  * @bh: The buffer to add
139  * @meta: True in the case of adding metadata
140  *
141  */
142
143 void gfs2_trans_add_bh(struct gfs2_glock *gl, struct buffer_head *bh, int meta)
144 {
145         struct gfs2_sbd *sdp = gl->gl_sbd;
146         struct gfs2_bufdata *bd;
147
148         bd = bh->b_private;
149         if (bd)
150                 gfs2_assert(sdp, bd->bd_gl == gl);
151         else {
152                 gfs2_attach_bufdata(gl, bh, meta);
153                 bd = bh->b_private;
154         }
155         lops_add(sdp, &bd->bd_le);
156 }
157
158 void gfs2_trans_add_revoke(struct gfs2_sbd *sdp, struct gfs2_bufdata *bd)
159 {
160         BUG_ON(!list_empty(&bd->bd_le.le_list));
161         BUG_ON(!list_empty(&bd->bd_ail_st_list));
162         BUG_ON(!list_empty(&bd->bd_ail_gl_list));
163         lops_init_le(&bd->bd_le, &gfs2_revoke_lops);
164         lops_add(sdp, &bd->bd_le);
165 }
166
167 void gfs2_trans_add_unrevoke(struct gfs2_sbd *sdp, u64 blkno, unsigned int len)
168 {
169         struct gfs2_bufdata *bd, *tmp;
170         struct gfs2_trans *tr = current->journal_info;
171         unsigned int n = len;
172
173         gfs2_log_lock(sdp);
174         list_for_each_entry_safe(bd, tmp, &sdp->sd_log_le_revoke, bd_le.le_list) {
175                 if ((bd->bd_blkno >= blkno) && (bd->bd_blkno < (blkno + len))) {
176                         list_del_init(&bd->bd_le.le_list);
177                         gfs2_assert_withdraw(sdp, sdp->sd_log_num_revoke);
178                         sdp->sd_log_num_revoke--;
179                         kmem_cache_free(gfs2_bufdata_cachep, bd);
180                         tr->tr_num_revoke_rm++;
181                         if (--n == 0)
182                                 break;
183                 }
184         }
185         gfs2_log_unlock(sdp);
186 }
187
188 void gfs2_trans_add_rg(struct gfs2_rgrpd *rgd)
189 {
190         lops_add(rgd->rd_sbd, &rgd->rd_le);
191 }
192