Merge tag 'for-linus-v3.9-rc1' of git://oss.sgi.com/xfs/xfs
[~shefty/rdma-dev.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         sb_start_intwrite(sdp->sd_vfs);
54         gfs2_holder_init(sdp->sd_trans_gl, LM_ST_SHARED, 0, &tr->tr_t_gh);
55
56         error = gfs2_glock_nq(&tr->tr_t_gh);
57         if (error)
58                 goto fail_holder_uninit;
59
60         error = gfs2_log_reserve(sdp, tr->tr_reserved);
61         if (error)
62                 goto fail_gunlock;
63
64         current->journal_info = tr;
65
66         return 0;
67
68 fail_gunlock:
69         gfs2_glock_dq(&tr->tr_t_gh);
70
71 fail_holder_uninit:
72         sb_end_intwrite(sdp->sd_vfs);
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 static void gfs2_print_trans(const struct gfs2_trans *tr)
97 {
98         print_symbol(KERN_WARNING "GFS2: Transaction created at: %s\n", tr->tr_ip);
99         printk(KERN_WARNING "GFS2: blocks=%u revokes=%u reserved=%u touched=%d\n",
100                tr->tr_blocks, tr->tr_revokes, tr->tr_reserved, tr->tr_touched);
101         printk(KERN_WARNING "GFS2: Buf %u/%u Databuf %u/%u Revoke %u/%u\n",
102                tr->tr_num_buf_new, tr->tr_num_buf_rm,
103                tr->tr_num_databuf_new, tr->tr_num_databuf_rm,
104                tr->tr_num_revoke, tr->tr_num_revoke_rm);
105 }
106
107 void gfs2_trans_end(struct gfs2_sbd *sdp)
108 {
109         struct gfs2_trans *tr = current->journal_info;
110         s64 nbuf;
111         BUG_ON(!tr);
112         current->journal_info = NULL;
113
114         if (!tr->tr_touched) {
115                 gfs2_log_release(sdp, tr->tr_reserved);
116                 if (tr->tr_t_gh.gh_gl) {
117                         gfs2_glock_dq(&tr->tr_t_gh);
118                         gfs2_holder_uninit(&tr->tr_t_gh);
119                         kfree(tr);
120                 }
121                 sb_end_intwrite(sdp->sd_vfs);
122                 return;
123         }
124
125         nbuf = tr->tr_num_buf_new + tr->tr_num_databuf_new;
126         nbuf -= tr->tr_num_buf_rm;
127         nbuf -= tr->tr_num_databuf_rm;
128
129         if (gfs2_assert_withdraw(sdp, (nbuf <= tr->tr_blocks) &&
130                                        (tr->tr_num_revoke <= tr->tr_revokes)))
131                 gfs2_print_trans(tr);
132
133         gfs2_log_commit(sdp, tr);
134         if (tr->tr_t_gh.gh_gl) {
135                 gfs2_glock_dq(&tr->tr_t_gh);
136                 gfs2_holder_uninit(&tr->tr_t_gh);
137                 kfree(tr);
138         }
139
140         if (sdp->sd_vfs->s_flags & MS_SYNCHRONOUS)
141                 gfs2_log_flush(sdp, NULL);
142         sb_end_intwrite(sdp->sd_vfs);
143 }
144
145 /**
146  * gfs2_trans_add_bh - Add a to-be-modified buffer to the current transaction
147  * @gl: the glock the buffer belongs to
148  * @bh: The buffer to add
149  * @meta: True in the case of adding metadata
150  *
151  */
152
153 void gfs2_trans_add_bh(struct gfs2_glock *gl, struct buffer_head *bh, int meta)
154 {
155         struct gfs2_sbd *sdp = gl->gl_sbd;
156         struct gfs2_bufdata *bd;
157
158         lock_buffer(bh);
159         gfs2_log_lock(sdp);
160         bd = bh->b_private;
161         if (bd)
162                 gfs2_assert(sdp, bd->bd_gl == gl);
163         else {
164                 gfs2_log_unlock(sdp);
165                 unlock_buffer(bh);
166                 gfs2_attach_bufdata(gl, bh, meta);
167                 bd = bh->b_private;
168                 lock_buffer(bh);
169                 gfs2_log_lock(sdp);
170         }
171         lops_add(sdp, bd);
172         gfs2_log_unlock(sdp);
173         unlock_buffer(bh);
174 }
175
176 void gfs2_trans_add_revoke(struct gfs2_sbd *sdp, struct gfs2_bufdata *bd)
177 {
178         BUG_ON(!list_empty(&bd->bd_list));
179         BUG_ON(!list_empty(&bd->bd_ail_st_list));
180         BUG_ON(!list_empty(&bd->bd_ail_gl_list));
181         lops_init_le(bd, &gfs2_revoke_lops);
182         lops_add(sdp, bd);
183 }
184
185 void gfs2_trans_add_unrevoke(struct gfs2_sbd *sdp, u64 blkno, unsigned int len)
186 {
187         struct gfs2_bufdata *bd, *tmp;
188         struct gfs2_trans *tr = current->journal_info;
189         unsigned int n = len;
190
191         gfs2_log_lock(sdp);
192         list_for_each_entry_safe(bd, tmp, &sdp->sd_log_le_revoke, bd_list) {
193                 if ((bd->bd_blkno >= blkno) && (bd->bd_blkno < (blkno + len))) {
194                         list_del_init(&bd->bd_list);
195                         gfs2_assert_withdraw(sdp, sdp->sd_log_num_revoke);
196                         sdp->sd_log_num_revoke--;
197                         kmem_cache_free(gfs2_bufdata_cachep, bd);
198                         tr->tr_num_revoke_rm++;
199                         if (--n == 0)
200                                 break;
201                 }
202         }
203         gfs2_log_unlock(sdp);
204 }
205