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
28static void gfs2_print_trans(struct gfs2_sbd *sdp, const struct gfs2_trans *tr)
29{
30 fs_warn(sdp, "Transaction created at: %pSR\n", (void *)tr->tr_ip);
31 fs_warn(sdp, "blocks=%u revokes=%u reserved=%u touched=%u\n",
32 tr->tr_blocks, tr->tr_revokes, tr->tr_reserved,
33 test_bit(TR_TOUCHED, &tr->tr_flags));
34 fs_warn(sdp, "Buf %u/%u Databuf %u/%u Revoke %u\n",
35 tr->tr_num_buf_new, tr->tr_num_buf_rm,
36 tr->tr_num_databuf_new, tr->tr_num_databuf_rm,
37 tr->tr_num_revoke);
38}
39
40int __gfs2_trans_begin(struct gfs2_trans *tr, struct gfs2_sbd *sdp,
41 unsigned int blocks, unsigned int revokes,
42 unsigned long ip)
43{
44 unsigned int extra_revokes;
45
46 if (current->journal_info) {
47 gfs2_print_trans(sdp, current->journal_info);
48 BUG();
49 }
50 BUG_ON(blocks == 0 && revokes == 0);
51
52 if (gfs2_withdrawn(sdp))
53 return -EROFS;
54
55 tr->tr_ip = ip;
56 tr->tr_blocks = blocks;
57 tr->tr_revokes = revokes;
58 tr->tr_reserved = GFS2_LOG_FLUSH_MIN_BLOCKS;
59 if (blocks) {
60 /*
61 * The reserved blocks are either used for data or metadata.
62 * We can have mixed data and metadata, each with its own log
63 * descriptor block; see calc_reserved().
64 */
65 tr->tr_reserved += blocks + 1 + DIV_ROUND_UP(blocks - 1, databuf_limit(sdp));
66 }
67 INIT_LIST_HEAD(list: &tr->tr_databuf);
68 INIT_LIST_HEAD(list: &tr->tr_buf);
69 INIT_LIST_HEAD(list: &tr->tr_list);
70 INIT_LIST_HEAD(list: &tr->tr_ail1_list);
71 INIT_LIST_HEAD(list: &tr->tr_ail2_list);
72
73 if (gfs2_assert_warn(sdp, tr->tr_reserved <= sdp->sd_jdesc->jd_blocks))
74 return -EINVAL;
75
76 sb_start_intwrite(sb: sdp->sd_vfs);
77
78 /*
79 * Try the reservations under sd_log_flush_lock to prevent log flushes
80 * from creating inconsistencies between the number of allocated and
81 * reserved revokes. If that fails, do a full-block allocation outside
82 * of the lock to avoid stalling log flushes. Then, allot the
83 * appropriate number of blocks to revokes, use as many revokes locally
84 * as needed, and "release" the surplus into the revokes pool.
85 */
86
87 down_read(sem: &sdp->sd_log_flush_lock);
88 if (unlikely(!test_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags)))
89 goto out_not_live;
90 if (gfs2_log_try_reserve(sdp, tr, extra_revokes: &extra_revokes))
91 goto reserved;
92
93 up_read(sem: &sdp->sd_log_flush_lock);
94 gfs2_log_reserve(sdp, tr, extra_revokes: &extra_revokes);
95 down_read(sem: &sdp->sd_log_flush_lock);
96 if (unlikely(!test_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags))) {
97 revokes = tr->tr_revokes + extra_revokes;
98 gfs2_log_release_revokes(sdp, revokes);
99 gfs2_log_release(sdp, blks: tr->tr_reserved);
100 goto out_not_live;
101 }
102
103reserved:
104 gfs2_log_release_revokes(sdp, revokes: extra_revokes);
105 current->journal_info = tr;
106 return 0;
107
108out_not_live:
109 up_read(sem: &sdp->sd_log_flush_lock);
110 sb_end_intwrite(sb: sdp->sd_vfs);
111 return -EROFS;
112}
113
114int gfs2_trans_begin(struct gfs2_sbd *sdp, unsigned int blocks,
115 unsigned int revokes)
116{
117 struct gfs2_trans *tr;
118 int error;
119
120 tr = kmem_cache_zalloc(gfs2_trans_cachep, GFP_NOFS);
121 if (!tr)
122 return -ENOMEM;
123 error = __gfs2_trans_begin(tr, sdp, blocks, revokes, _RET_IP_);
124 if (error)
125 kmem_cache_free(s: gfs2_trans_cachep, objp: tr);
126 return error;
127}
128
129void gfs2_trans_end(struct gfs2_sbd *sdp)
130{
131 struct gfs2_trans *tr = current->journal_info;
132 s64 nbuf;
133
134 current->journal_info = NULL;
135
136 if (!test_bit(TR_TOUCHED, &tr->tr_flags)) {
137 gfs2_log_release_revokes(sdp, revokes: tr->tr_revokes);
138 up_read(sem: &sdp->sd_log_flush_lock);
139 gfs2_log_release(sdp, blks: tr->tr_reserved);
140 if (!test_bit(TR_ONSTACK, &tr->tr_flags))
141 gfs2_trans_free(sdp, tr);
142 sb_end_intwrite(sb: sdp->sd_vfs);
143 return;
144 }
145
146 gfs2_log_release_revokes(sdp, revokes: tr->tr_revokes - tr->tr_num_revoke);
147
148 nbuf = tr->tr_num_buf_new + tr->tr_num_databuf_new;
149 nbuf -= tr->tr_num_buf_rm;
150 nbuf -= tr->tr_num_databuf_rm;
151
152 if (gfs2_assert_withdraw(sdp, nbuf <= tr->tr_blocks) ||
153 gfs2_assert_withdraw(sdp, tr->tr_num_revoke <= tr->tr_revokes))
154 gfs2_print_trans(sdp, tr);
155
156 gfs2_log_commit(sdp, trans: tr);
157 if (!test_bit(TR_ONSTACK, &tr->tr_flags) &&
158 !test_bit(TR_ATTACHED, &tr->tr_flags))
159 gfs2_trans_free(sdp, tr);
160 up_read(sem: &sdp->sd_log_flush_lock);
161
162 if (sdp->sd_vfs->s_flags & SB_SYNCHRONOUS)
163 gfs2_log_flush(sdp, NULL, GFS2_LOG_HEAD_FLUSH_NORMAL |
164 GFS2_LFC_TRANS_END);
165 sb_end_intwrite(sb: sdp->sd_vfs);
166}
167
168static struct gfs2_bufdata *gfs2_alloc_bufdata(struct gfs2_glock *gl,
169 struct buffer_head *bh)
170{
171 struct gfs2_bufdata *bd;
172
173 bd = kmem_cache_zalloc(gfs2_bufdata_cachep, GFP_NOFS | __GFP_NOFAIL);
174 bd->bd_bh = bh;
175 bd->bd_gl = gl;
176 INIT_LIST_HEAD(list: &bd->bd_list);
177 INIT_LIST_HEAD(list: &bd->bd_ail_st_list);
178 INIT_LIST_HEAD(list: &bd->bd_ail_gl_list);
179 bh->b_private = bd;
180 return bd;
181}
182
183/**
184 * gfs2_trans_add_data - Add a databuf to the transaction.
185 * @gl: The inode glock associated with the buffer
186 * @bh: The buffer to add
187 *
188 * This is used in journaled data mode.
189 * We need to journal the data block in the same way as metadata in
190 * the functions above. The difference is that here we have a tag
191 * which is two __be64's being the block number (as per meta data)
192 * and a flag which says whether the data block needs escaping or
193 * not. This means we need a new log entry for each 251 or so data
194 * blocks, which isn't an enormous overhead but twice as much as
195 * for normal metadata blocks.
196 */
197void gfs2_trans_add_data(struct gfs2_glock *gl, struct buffer_head *bh)
198{
199 struct gfs2_trans *tr = current->journal_info;
200 struct gfs2_sbd *sdp = gl->gl_name.ln_sbd;
201 struct gfs2_bufdata *bd;
202
203 lock_buffer(bh);
204 if (buffer_pinned(bh)) {
205 set_bit(nr: TR_TOUCHED, addr: &tr->tr_flags);
206 goto out;
207 }
208 gfs2_log_lock(sdp);
209 bd = bh->b_private;
210 if (bd == NULL) {
211 gfs2_log_unlock(sdp);
212 unlock_buffer(bh);
213 if (bh->b_private == NULL)
214 bd = gfs2_alloc_bufdata(gl, bh);
215 else
216 bd = bh->b_private;
217 lock_buffer(bh);
218 gfs2_log_lock(sdp);
219 }
220 gfs2_assert(sdp, bd->bd_gl == gl);
221 set_bit(nr: TR_TOUCHED, addr: &tr->tr_flags);
222 if (list_empty(head: &bd->bd_list)) {
223 set_bit(nr: GLF_LFLUSH, addr: &bd->bd_gl->gl_flags);
224 set_bit(nr: GLF_DIRTY, addr: &bd->bd_gl->gl_flags);
225 gfs2_pin(sdp, bh: bd->bd_bh);
226 tr->tr_num_databuf_new++;
227 list_add_tail(new: &bd->bd_list, head: &tr->tr_databuf);
228 }
229 gfs2_log_unlock(sdp);
230out:
231 unlock_buffer(bh);
232}
233
234void gfs2_trans_add_databufs(struct gfs2_glock *gl, struct folio *folio,
235 size_t from, size_t len)
236{
237 struct buffer_head *head = folio_buffers(folio);
238 unsigned int bsize = head->b_size;
239 struct buffer_head *bh;
240 size_t to = from + len;
241 size_t start, end;
242
243 for (bh = head, start = 0; bh != head || !start;
244 bh = bh->b_this_page, start = end) {
245 end = start + bsize;
246 if (end <= from)
247 continue;
248 if (start >= to)
249 break;
250 set_buffer_uptodate(bh);
251 gfs2_trans_add_data(gl, bh);
252 }
253}
254
255void gfs2_trans_add_meta(struct gfs2_glock *gl, struct buffer_head *bh)
256{
257
258 struct gfs2_sbd *sdp = gl->gl_name.ln_sbd;
259 struct super_block *sb = sdp->sd_vfs;
260 struct gfs2_bufdata *bd;
261 struct gfs2_meta_header *mh;
262 struct gfs2_trans *tr = current->journal_info;
263
264 lock_buffer(bh);
265 if (buffer_pinned(bh)) {
266 set_bit(nr: TR_TOUCHED, addr: &tr->tr_flags);
267 goto out;
268 }
269 gfs2_log_lock(sdp);
270 bd = bh->b_private;
271 if (bd == NULL) {
272 gfs2_log_unlock(sdp);
273 unlock_buffer(bh);
274 folio_lock(folio: bh->b_folio);
275 if (bh->b_private == NULL)
276 bd = gfs2_alloc_bufdata(gl, bh);
277 else
278 bd = bh->b_private;
279 folio_unlock(folio: bh->b_folio);
280 lock_buffer(bh);
281 gfs2_log_lock(sdp);
282 }
283 gfs2_assert(sdp, bd->bd_gl == gl);
284 set_bit(nr: TR_TOUCHED, addr: &tr->tr_flags);
285 if (!list_empty(head: &bd->bd_list))
286 goto out_unlock;
287 set_bit(nr: GLF_LFLUSH, addr: &bd->bd_gl->gl_flags);
288 set_bit(nr: GLF_DIRTY, addr: &bd->bd_gl->gl_flags);
289 mh = (struct gfs2_meta_header *)bd->bd_bh->b_data;
290 if (unlikely(mh->mh_magic != cpu_to_be32(GFS2_MAGIC))) {
291 fs_err(sdp, "Attempting to add uninitialised block to "
292 "journal (inplace block=%lld)\n",
293 (unsigned long long)bd->bd_bh->b_blocknr);
294 BUG();
295 }
296 if (gfs2_withdrawn(sdp)) {
297 fs_info(sdp, "GFS2:adding buf while withdrawn! 0x%llx\n",
298 (unsigned long long)bd->bd_bh->b_blocknr);
299 goto out_unlock;
300 }
301 if (unlikely(sb->s_writers.frozen == SB_FREEZE_COMPLETE)) {
302 fs_info(sdp, "GFS2:adding buf while frozen\n");
303 gfs2_withdraw(sdp);
304 goto out_unlock;
305 }
306 gfs2_pin(sdp, bh: bd->bd_bh);
307 mh->__pad0 = cpu_to_be64(0);
308 mh->mh_jid = cpu_to_be32(sdp->sd_jdesc->jd_jid);
309 list_add(new: &bd->bd_list, head: &tr->tr_buf);
310 tr->tr_num_buf_new++;
311out_unlock:
312 gfs2_log_unlock(sdp);
313out:
314 unlock_buffer(bh);
315}
316
317void gfs2_trans_add_revoke(struct gfs2_sbd *sdp, struct gfs2_bufdata *bd)
318{
319 struct gfs2_trans *tr = current->journal_info;
320
321 BUG_ON(!list_empty(&bd->bd_list));
322 gfs2_add_revoke(sdp, bd);
323 set_bit(nr: TR_TOUCHED, addr: &tr->tr_flags);
324 tr->tr_num_revoke++;
325}
326
327void gfs2_trans_remove_revoke(struct gfs2_sbd *sdp, u64 blkno, unsigned int len)
328{
329 struct gfs2_bufdata *bd, *tmp;
330 unsigned int n = len;
331
332 gfs2_log_lock(sdp);
333 list_for_each_entry_safe(bd, tmp, &sdp->sd_log_revokes, bd_list) {
334 if ((bd->bd_blkno >= blkno) && (bd->bd_blkno < (blkno + len))) {
335 list_del_init(entry: &bd->bd_list);
336 gfs2_assert_withdraw(sdp, sdp->sd_log_num_revoke);
337 sdp->sd_log_num_revoke--;
338 if (bd->bd_gl)
339 gfs2_glock_remove_revoke(gl: bd->bd_gl);
340 kmem_cache_free(s: gfs2_bufdata_cachep, objp: bd);
341 gfs2_log_release_revokes(sdp, revokes: 1);
342 if (--n == 0)
343 break;
344 }
345 }
346 gfs2_log_unlock(sdp);
347}
348
349void gfs2_trans_free(struct gfs2_sbd *sdp, struct gfs2_trans *tr)
350{
351 if (tr == NULL)
352 return;
353
354 gfs2_assert_warn(sdp, list_empty(&tr->tr_ail1_list));
355 gfs2_assert_warn(sdp, list_empty(&tr->tr_ail2_list));
356 gfs2_assert_warn(sdp, list_empty(&tr->tr_databuf));
357 gfs2_assert_warn(sdp, list_empty(&tr->tr_buf));
358 kmem_cache_free(s: gfs2_trans_cachep, objp: tr);
359}
360

source code of linux/fs/gfs2/trans.c