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1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (C) Sistina Software, Inc.  1997-2003 All rights reserved.
4  * Copyright (C) 2004-2006 Red Hat, Inc.  All rights reserved.
5  */
6
7 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
8
9 #include <linux/sched.h>
10 #include <linux/slab.h>
11 #include <linux/spinlock.h>
12 #include <linux/completion.h>
13 #include <linux/buffer_head.h>
14 #include <linux/kallsyms.h>
15 #include <linux/gfs2_ondisk.h>
16
17 #include "gfs2.h"
18 #include "incore.h"
19 #include "glock.h"
20 #include "inode.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 = _RET_IP_;
45         tr->tr_blocks = blocks;
46         tr->tr_revokes = revokes;
47         tr->tr_reserved = 1;
48         set_bit(TR_ALLOCED, &tr->tr_flags);
49         if (blocks)
50                 tr->tr_reserved += 6 + blocks;
51         if (revokes)
52                 tr->tr_reserved += gfs2_struct2blk(sdp, revokes);
53         INIT_LIST_HEAD(&tr->tr_databuf);
54         INIT_LIST_HEAD(&tr->tr_buf);
55
56         sb_start_intwrite(sdp->sd_vfs);
57
58         error = gfs2_log_reserve(sdp, tr->tr_reserved);
59         if (error)
60                 goto fail;
61
62         current->journal_info = tr;
63
64         return 0;
65
66 fail:
67         sb_end_intwrite(sdp->sd_vfs);
68         kfree(tr);
69
70         return error;
71 }
72
73 static void gfs2_print_trans(struct gfs2_sbd *sdp, const struct gfs2_trans *tr)
74 {
75         fs_warn(sdp, "Transaction created at: %pSR\n", (void *)tr->tr_ip);
76         fs_warn(sdp, "blocks=%u revokes=%u reserved=%u touched=%u\n",
77                 tr->tr_blocks, tr->tr_revokes, tr->tr_reserved,
78                 test_bit(TR_TOUCHED, &tr->tr_flags));
79         fs_warn(sdp, "Buf %u/%u Databuf %u/%u Revoke %u/%u\n",
80                 tr->tr_num_buf_new, tr->tr_num_buf_rm,
81                 tr->tr_num_databuf_new, tr->tr_num_databuf_rm,
82                 tr->tr_num_revoke, tr->tr_num_revoke_rm);
83 }
84
85 void gfs2_trans_end(struct gfs2_sbd *sdp)
86 {
87         struct gfs2_trans *tr = current->journal_info;
88         s64 nbuf;
89         int alloced = test_bit(TR_ALLOCED, &tr->tr_flags);
90
91         current->journal_info = NULL;
92
93         if (!test_bit(TR_TOUCHED, &tr->tr_flags)) {
94                 gfs2_log_release(sdp, tr->tr_reserved);
95                 if (alloced) {
96                         kfree(tr);
97                         sb_end_intwrite(sdp->sd_vfs);
98                 }
99                 return;
100         }
101
102         nbuf = tr->tr_num_buf_new + tr->tr_num_databuf_new;
103         nbuf -= tr->tr_num_buf_rm;
104         nbuf -= tr->tr_num_databuf_rm;
105
106         if (gfs2_assert_withdraw(sdp, (nbuf <= tr->tr_blocks) &&
107                                        (tr->tr_num_revoke <= tr->tr_revokes)))
108                 gfs2_print_trans(sdp, tr);
109
110         gfs2_log_commit(sdp, tr);
111         if (alloced && !test_bit(TR_ATTACHED, &tr->tr_flags))
112                 kfree(tr);
113         up_read(&sdp->sd_log_flush_lock);
114
115         if (sdp->sd_vfs->s_flags & SB_SYNCHRONOUS)
116                 gfs2_log_flush(sdp, NULL, GFS2_LOG_HEAD_FLUSH_NORMAL |
117                                GFS2_LFC_TRANS_END);
118         if (alloced)
119                 sb_end_intwrite(sdp->sd_vfs);
120 }
121
122 static struct gfs2_bufdata *gfs2_alloc_bufdata(struct gfs2_glock *gl,
123                                                struct buffer_head *bh)
124 {
125         struct gfs2_bufdata *bd;
126
127         bd = kmem_cache_zalloc(gfs2_bufdata_cachep, GFP_NOFS | __GFP_NOFAIL);
128         bd->bd_bh = bh;
129         bd->bd_gl = gl;
130         INIT_LIST_HEAD(&bd->bd_list);
131         bh->b_private = bd;
132         return bd;
133 }
134
135 /**
136  * gfs2_trans_add_data - Add a databuf to the transaction.
137  * @gl: The inode glock associated with the buffer
138  * @bh: The buffer to add
139  *
140  * This is used in journaled data mode.
141  * We need to journal the data block in the same way as metadata in
142  * the functions above. The difference is that here we have a tag
143  * which is two __be64's being the block number (as per meta data)
144  * and a flag which says whether the data block needs escaping or
145  * not. This means we need a new log entry for each 251 or so data
146  * blocks, which isn't an enormous overhead but twice as much as
147  * for normal metadata blocks.
148  */
149 void gfs2_trans_add_data(struct gfs2_glock *gl, struct buffer_head *bh)
150 {
151         struct gfs2_trans *tr = current->journal_info;
152         struct gfs2_sbd *sdp = gl->gl_name.ln_sbd;
153         struct gfs2_bufdata *bd;
154
155         lock_buffer(bh);
156         if (buffer_pinned(bh)) {
157                 set_bit(TR_TOUCHED, &tr->tr_flags);
158                 goto out;
159         }
160         gfs2_log_lock(sdp);
161         bd = bh->b_private;
162         if (bd == NULL) {
163                 gfs2_log_unlock(sdp);
164                 unlock_buffer(bh);
165                 if (bh->b_private == NULL)
166                         bd = gfs2_alloc_bufdata(gl, bh);
167                 else
168                         bd = bh->b_private;
169                 lock_buffer(bh);
170                 gfs2_log_lock(sdp);
171         }
172         gfs2_assert(sdp, bd->bd_gl == gl);
173         set_bit(TR_TOUCHED, &tr->tr_flags);
174         if (list_empty(&bd->bd_list)) {
175                 set_bit(GLF_LFLUSH, &bd->bd_gl->gl_flags);
176                 set_bit(GLF_DIRTY, &bd->bd_gl->gl_flags);
177                 gfs2_pin(sdp, bd->bd_bh);
178                 tr->tr_num_databuf_new++;
179                 list_add_tail(&bd->bd_list, &tr->tr_databuf);
180         }
181         gfs2_log_unlock(sdp);
182 out:
183         unlock_buffer(bh);
184 }
185
186 void gfs2_trans_add_meta(struct gfs2_glock *gl, struct buffer_head *bh)
187 {
188
189         struct gfs2_sbd *sdp = gl->gl_name.ln_sbd;
190         struct gfs2_bufdata *bd;
191         struct gfs2_meta_header *mh;
192         struct gfs2_trans *tr = current->journal_info;
193         enum gfs2_freeze_state state = atomic_read(&sdp->sd_freeze_state);
194
195         lock_buffer(bh);
196         if (buffer_pinned(bh)) {
197                 set_bit(TR_TOUCHED, &tr->tr_flags);
198                 goto out;
199         }
200         gfs2_log_lock(sdp);
201         bd = bh->b_private;
202         if (bd == NULL) {
203                 gfs2_log_unlock(sdp);
204                 unlock_buffer(bh);
205                 lock_page(bh->b_page);
206                 if (bh->b_private == NULL)
207                         bd = gfs2_alloc_bufdata(gl, bh);
208                 else
209                         bd = bh->b_private;
210                 unlock_page(bh->b_page);
211                 lock_buffer(bh);
212                 gfs2_log_lock(sdp);
213         }
214         gfs2_assert(sdp, bd->bd_gl == gl);
215         set_bit(TR_TOUCHED, &tr->tr_flags);
216         if (!list_empty(&bd->bd_list))
217                 goto out_unlock;
218         set_bit(GLF_LFLUSH, &bd->bd_gl->gl_flags);
219         set_bit(GLF_DIRTY, &bd->bd_gl->gl_flags);
220         mh = (struct gfs2_meta_header *)bd->bd_bh->b_data;
221         if (unlikely(mh->mh_magic != cpu_to_be32(GFS2_MAGIC))) {
222                 fs_err(sdp, "Attempting to add uninitialised block to "
223                        "journal (inplace block=%lld)\n",
224                        (unsigned long long)bd->bd_bh->b_blocknr);
225                 BUG();
226         }
227         if (unlikely(state == SFS_FROZEN)) {
228                 fs_info(sdp, "GFS2:adding buf while frozen\n");
229                 gfs2_assert_withdraw(sdp, 0);
230         }
231         if (unlikely(gfs2_withdrawn(sdp))) {
232                 fs_info(sdp, "GFS2:adding buf while withdrawn! 0x%llx\n",
233                         (unsigned long long)bd->bd_bh->b_blocknr);
234         }
235         gfs2_pin(sdp, bd->bd_bh);
236         mh->__pad0 = cpu_to_be64(0);
237         mh->mh_jid = cpu_to_be32(sdp->sd_jdesc->jd_jid);
238         list_add(&bd->bd_list, &tr->tr_buf);
239         tr->tr_num_buf_new++;
240 out_unlock:
241         gfs2_log_unlock(sdp);
242 out:
243         unlock_buffer(bh);
244 }
245
246 void gfs2_trans_add_revoke(struct gfs2_sbd *sdp, struct gfs2_bufdata *bd)
247 {
248         struct gfs2_trans *tr = current->journal_info;
249
250         BUG_ON(!list_empty(&bd->bd_list));
251         gfs2_add_revoke(sdp, bd);
252         set_bit(TR_TOUCHED, &tr->tr_flags);
253         tr->tr_num_revoke++;
254 }
255
256 void gfs2_trans_remove_revoke(struct gfs2_sbd *sdp, u64 blkno, unsigned int len)
257 {
258         struct gfs2_bufdata *bd, *tmp;
259         struct gfs2_trans *tr = current->journal_info;
260         unsigned int n = len;
261
262         gfs2_log_lock(sdp);
263         list_for_each_entry_safe(bd, tmp, &sdp->sd_log_revokes, bd_list) {
264                 if ((bd->bd_blkno >= blkno) && (bd->bd_blkno < (blkno + len))) {
265                         list_del_init(&bd->bd_list);
266                         gfs2_assert_withdraw(sdp, sdp->sd_log_num_revoke);
267                         sdp->sd_log_num_revoke--;
268                         if (bd->bd_gl)
269                                 gfs2_glock_remove_revoke(bd->bd_gl);
270                         kmem_cache_free(gfs2_bufdata_cachep, bd);
271                         tr->tr_num_revoke_rm++;
272                         if (--n == 0)
273                                 break;
274                 }
275         }
276         gfs2_log_unlock(sdp);
277 }
278
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