[GFS2] The core of GFS2
[linux-2.6.git] / fs / gfs2 / trans.c
1 /*
2  * Copyright (C) Sistina Software, Inc.  1997-2003 All rights reserved.
3  * Copyright (C) 2004-2005 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 v.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 <asm/semaphore.h>
16
17 #include "gfs2.h"
18 #include "glock.h"
19 #include "log.h"
20 #include "lops.h"
21 #include "meta_io.h"
22 #include "trans.h"
23
24 int gfs2_trans_begin_i(struct gfs2_sbd *sdp, unsigned int blocks,
25                        unsigned int revokes, char *file, unsigned int line)
26 {
27         struct gfs2_trans *tr;
28         int error;
29
30         if (gfs2_assert_warn(sdp, !get_transaction) ||
31             gfs2_assert_warn(sdp, blocks || revokes)) {
32                 fs_warn(sdp, "(%s, %u)\n", file, line);
33                 return -EINVAL;
34         }
35
36         tr = kzalloc(sizeof(struct gfs2_trans), GFP_KERNEL);
37         if (!tr)
38                 return -ENOMEM;
39
40         tr->tr_file = file;
41         tr->tr_line = line;
42         tr->tr_blocks = blocks;
43         tr->tr_revokes = revokes;
44         tr->tr_reserved = 1;
45         if (blocks)
46                 tr->tr_reserved += 1 + blocks;
47         if (revokes)
48                 tr->tr_reserved += gfs2_struct2blk(sdp, revokes,
49                                                    sizeof(uint64_t));
50         INIT_LIST_HEAD(&tr->tr_list_buf);
51
52         error = -ENOMEM;
53         tr->tr_t_gh = gfs2_holder_get(sdp->sd_trans_gl, LM_ST_SHARED,
54                                       GL_NEVER_RECURSE, GFP_KERNEL);
55         if (!tr->tr_t_gh)
56                 goto fail;
57
58         error = gfs2_glock_nq(tr->tr_t_gh);
59         if (error)
60                 goto fail_holder_put;
61
62         if (!test_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags)) {
63                 tr->tr_t_gh->gh_flags |= GL_NOCACHE;
64                 error = -EROFS;
65                 goto fail_gunlock;
66         }
67
68         error = gfs2_log_reserve(sdp, tr->tr_reserved);
69         if (error)
70                 goto fail_gunlock;
71
72         set_transaction(tr);
73
74         return 0;
75
76  fail_gunlock:
77         gfs2_glock_dq(tr->tr_t_gh);
78
79  fail_holder_put:
80         gfs2_holder_put(tr->tr_t_gh);
81
82  fail:
83         kfree(tr);
84
85         return error;
86 }
87
88 void gfs2_trans_end(struct gfs2_sbd *sdp)
89 {
90         struct gfs2_trans *tr;
91         struct gfs2_holder *t_gh;
92
93         tr = get_transaction;
94         set_transaction(NULL);
95
96         if (gfs2_assert_warn(sdp, tr))
97                 return;
98
99         t_gh = tr->tr_t_gh;
100         tr->tr_t_gh = NULL;
101
102         if (!tr->tr_touched) {
103                 gfs2_log_release(sdp, tr->tr_reserved);
104                 kfree(tr);
105
106                 gfs2_glock_dq(t_gh);
107                 gfs2_holder_put(t_gh);
108
109                 return;
110         }
111
112         if (gfs2_assert_withdraw(sdp, tr->tr_num_buf <= tr->tr_blocks))
113                 fs_err(sdp, "tr_num_buf = %u, tr_blocks = %u "
114                        "tr_file = %s, tr_line = %u\n",
115                        tr->tr_num_buf, tr->tr_blocks,
116                        tr->tr_file, tr->tr_line);
117         if (gfs2_assert_withdraw(sdp, tr->tr_num_revoke <= tr->tr_revokes))
118                 fs_err(sdp, "tr_num_revoke = %u, tr_revokes = %u "
119                        "tr_file = %s, tr_line = %u\n",
120                        tr->tr_num_revoke, tr->tr_revokes,
121                        tr->tr_file, tr->tr_line);
122
123         gfs2_log_commit(sdp, tr);
124
125         gfs2_glock_dq(t_gh);
126         gfs2_holder_put(t_gh);
127
128         if (sdp->sd_vfs->s_flags & MS_SYNCHRONOUS)
129                 gfs2_log_flush(sdp);
130 }
131
132 void gfs2_trans_add_gl(struct gfs2_glock *gl)
133 {
134         lops_add(gl->gl_sbd, &gl->gl_le);
135 }
136
137 /**
138  * gfs2_trans_add_bh - Add a to-be-modified buffer to the current transaction
139  * @gl: the glock the buffer belongs to
140  * @bh: The buffer to add
141  *
142  */
143
144 void gfs2_trans_add_bh(struct gfs2_glock *gl, struct buffer_head *bh)
145 {
146         struct gfs2_sbd *sdp = gl->gl_sbd;
147         struct gfs2_bufdata *bd;
148
149         bd = get_v2bd(bh);
150         if (bd)
151                 gfs2_assert(sdp, bd->bd_gl == gl);
152         else {
153                 gfs2_meta_attach_bufdata(gl, bh);
154                 bd = get_v2bd(bh);
155         }
156
157         lops_add(sdp, &bd->bd_le);
158 }
159
160 void gfs2_trans_add_revoke(struct gfs2_sbd *sdp, uint64_t blkno)
161 {
162         struct gfs2_revoke *rv = kmalloc(sizeof(struct gfs2_revoke),
163                                          GFP_KERNEL | __GFP_NOFAIL);
164         lops_init_le(&rv->rv_le, &gfs2_revoke_lops);
165         rv->rv_blkno = blkno;
166         lops_add(sdp, &rv->rv_le);
167 }
168
169 void gfs2_trans_add_unrevoke(struct gfs2_sbd *sdp, uint64_t blkno)
170 {
171         struct gfs2_revoke *rv;
172         int found = 0;
173
174         gfs2_log_lock(sdp);
175
176         list_for_each_entry(rv, &sdp->sd_log_le_revoke, rv_le.le_list) {
177                 if (rv->rv_blkno == blkno) {
178                         list_del(&rv->rv_le.le_list);
179                         gfs2_assert_withdraw(sdp, sdp->sd_log_num_revoke);
180                         sdp->sd_log_num_revoke--;
181                         found = 1;
182                         break;
183                 }
184         }
185
186         gfs2_log_unlock(sdp);
187
188         if (found) {
189                 kfree(rv);
190                 get_transaction->tr_num_revoke_rm++;
191         }
192 }
193
194 void gfs2_trans_add_rg(struct gfs2_rgrpd *rgd)
195 {
196         lops_add(rgd->rd_sbd, &rgd->rd_le);
197 }
198
199 void gfs2_trans_add_databuf(struct gfs2_sbd *sdp, struct buffer_head *bh)
200 {
201         struct gfs2_databuf *db;
202
203         db = get_v2db(bh);
204         if (!db) {
205                 db = kmalloc(sizeof(struct gfs2_databuf),
206                              GFP_KERNEL | __GFP_NOFAIL);
207                 lops_init_le(&db->db_le, &gfs2_databuf_lops);
208                 get_bh(bh);
209                 db->db_bh = bh;
210                 set_v2db(bh, db);
211                 lops_add(sdp, &db->db_le);
212         }
213 }
214