device-dax: don't leak kernel memory to user space after unloading kmem
[linux-block.git] / fs / gfs2 / trans.c
CommitLineData
7336d0e6 1// SPDX-License-Identifier: GPL-2.0-only
b3b94faa
DT
2/*
3 * Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved.
3a8a9a10 4 * Copyright (C) 2004-2006 Red Hat, Inc. All rights reserved.
b3b94faa
DT
5 */
6
d77d1b58
JP
7#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
8
b3b94faa
DT
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>
d0dc80db 14#include <linux/kallsyms.h>
f057f6cd 15#include <linux/gfs2_ondisk.h>
b3b94faa
DT
16
17#include "gfs2.h"
5c676f6d 18#include "incore.h"
b3b94faa 19#include "glock.h"
767f433f 20#include "inode.h"
b3b94faa
DT
21#include "log.h"
22#include "lops.h"
23#include "meta_io.h"
24#include "trans.h"
5c676f6d 25#include "util.h"
5e687eac 26#include "trace_gfs2.h"
b3b94faa 27
d0dc80db
SW
28int gfs2_trans_begin(struct gfs2_sbd *sdp, unsigned int blocks,
29 unsigned int revokes)
b3b94faa
DT
30{
31 struct gfs2_trans *tr;
32 int error;
33
d0dc80db
SW
34 BUG_ON(current->journal_info);
35 BUG_ON(blocks == 0 && revokes == 0);
b3b94faa 36
a1c0643f
SW
37 if (!test_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags))
38 return -EROFS;
39
f55ab26a 40 tr = kzalloc(sizeof(struct gfs2_trans), GFP_NOFS);
b3b94faa
DT
41 if (!tr)
42 return -ENOMEM;
43
d29c0afe 44 tr->tr_ip = _RET_IP_;
b3b94faa
DT
45 tr->tr_blocks = blocks;
46 tr->tr_revokes = revokes;
47 tr->tr_reserved = 1;
9862ca05 48 set_bit(TR_ALLOCED, &tr->tr_flags);
b3b94faa 49 if (blocks)
f4154ea0 50 tr->tr_reserved += 6 + blocks;
b3b94faa 51 if (revokes)
2e9eeaa1 52 tr->tr_reserved += gfs2_struct2blk(sdp, revokes);
d69a3c65
SW
53 INIT_LIST_HEAD(&tr->tr_databuf);
54 INIT_LIST_HEAD(&tr->tr_buf);
55
39263d5e 56 sb_start_intwrite(sdp->sd_vfs);
b3b94faa 57
b3b94faa
DT
58 error = gfs2_log_reserve(sdp, tr->tr_reserved);
59 if (error)
24972557 60 goto fail;
b3b94faa 61
5c676f6d 62 current->journal_info = tr;
b3b94faa
DT
63
64 return 0;
65
24972557 66fail:
39263d5e 67 sb_end_intwrite(sdp->sd_vfs);
b3b94faa
DT
68 kfree(tr);
69
70 return error;
71}
72
e54c78a2 73static void gfs2_print_trans(struct gfs2_sbd *sdp, const struct gfs2_trans *tr)
c50b91c4 74{
e54c78a2
BP
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",
9862ca05
BP
77 tr->tr_blocks, tr->tr_revokes, tr->tr_reserved,
78 test_bit(TR_TOUCHED, &tr->tr_flags));
a31b4ec5 79 fs_warn(sdp, "Buf %u/%u Databuf %u/%u Revoke %u/%u\n",
d77d1b58
JP
80 tr->tr_num_buf_new, tr->tr_num_buf_rm,
81 tr->tr_num_databuf_new, tr->tr_num_databuf_rm,
a31b4ec5 82 tr->tr_num_revoke, tr->tr_num_revoke_rm);
c50b91c4
SW
83}
84
b3b94faa
DT
85void gfs2_trans_end(struct gfs2_sbd *sdp)
86{
f4154ea0 87 struct gfs2_trans *tr = current->journal_info;
c50b91c4 88 s64 nbuf;
9862ca05 89 int alloced = test_bit(TR_ALLOCED, &tr->tr_flags);
2e60d768 90
5c676f6d 91 current->journal_info = NULL;
b3b94faa 92
9862ca05 93 if (!test_bit(TR_TOUCHED, &tr->tr_flags)) {
b3b94faa 94 gfs2_log_release(sdp, tr->tr_reserved);
2e60d768 95 if (alloced) {
d8348de0 96 kfree(tr);
2e60d768
BM
97 sb_end_intwrite(sdp->sd_vfs);
98 }
b3b94faa
DT
99 return;
100 }
101
c50b91c4
SW
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)))
e54c78a2 108 gfs2_print_trans(sdp, tr);
b3b94faa
DT
109
110 gfs2_log_commit(sdp, tr);
9862ca05
BP
111 if (alloced && !test_bit(TR_ATTACHED, &tr->tr_flags))
112 kfree(tr);
16ca9412 113 up_read(&sdp->sd_log_flush_lock);
b3b94faa 114
1751e8a6 115 if (sdp->sd_vfs->s_flags & SB_SYNCHRONOUS)
805c0907
BP
116 gfs2_log_flush(sdp, NULL, GFS2_LOG_HEAD_FLUSH_NORMAL |
117 GFS2_LFC_TRANS_END);
2e60d768
BM
118 if (alloced)
119 sb_end_intwrite(sdp->sd_vfs);
b3b94faa
DT
120}
121
c76c4d96 122static struct gfs2_bufdata *gfs2_alloc_bufdata(struct gfs2_glock *gl,
cbbe76c8 123 struct buffer_head *bh)
c76c4d96
SW
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;
c76c4d96
SW
130 INIT_LIST_HEAD(&bd->bd_list);
131 bh->b_private = bd;
132 return bd;
133}
134
b3b94faa 135/**
45138990
SW
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
b3b94faa 139 *
845802b1
AG
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.
b3b94faa 148 */
45138990 149void gfs2_trans_add_data(struct gfs2_glock *gl, struct buffer_head *bh)
767f433f
SW
150{
151 struct gfs2_trans *tr = current->journal_info;
15562c43 152 struct gfs2_sbd *sdp = gl->gl_name.ln_sbd;
45138990 153 struct gfs2_bufdata *bd;
767f433f 154
96e5d1d3 155 lock_buffer(bh);
aacee720
BP
156 if (buffer_pinned(bh)) {
157 set_bit(TR_TOUCHED, &tr->tr_flags);
158 goto out;
159 }
96e5d1d3 160 gfs2_log_lock(sdp);
5c676f6d 161 bd = bh->b_private;
c76c4d96 162 if (bd == NULL) {
96e5d1d3
BM
163 gfs2_log_unlock(sdp);
164 unlock_buffer(bh);
c76c4d96 165 if (bh->b_private == NULL)
cbbe76c8 166 bd = gfs2_alloc_bufdata(gl, bh);
491e94f7
BP
167 else
168 bd = bh->b_private;
96e5d1d3
BM
169 lock_buffer(bh);
170 gfs2_log_lock(sdp);
b3b94faa 171 }
c76c4d96 172 gfs2_assert(sdp, bd->bd_gl == gl);
9862ca05 173 set_bit(TR_TOUCHED, &tr->tr_flags);
45138990
SW
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++;
d69a3c65 179 list_add_tail(&bd->bd_list, &tr->tr_databuf);
45138990 180 }
96e5d1d3 181 gfs2_log_unlock(sdp);
aacee720 182out:
96e5d1d3 183 unlock_buffer(bh);
b3b94faa
DT
184}
185
192738b7 186void gfs2_trans_add_meta(struct gfs2_glock *gl, struct buffer_head *bh)
350a9b0a 187{
192738b7
BP
188
189 struct gfs2_sbd *sdp = gl->gl_name.ln_sbd;
190 struct gfs2_bufdata *bd;
767f433f 191 struct gfs2_meta_header *mh;
aacee720 192 struct gfs2_trans *tr = current->journal_info;
2e60d768 193 enum gfs2_freeze_state state = atomic_read(&sdp->sd_freeze_state);
767f433f 194
192738b7 195 lock_buffer(bh);
aacee720
BP
196 if (buffer_pinned(bh)) {
197 set_bit(TR_TOUCHED, &tr->tr_flags);
198 goto out;
199 }
192738b7
BP
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)
cbbe76c8 207 bd = gfs2_alloc_bufdata(gl, bh);
192738b7
BP
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);
9862ca05 215 set_bit(TR_TOUCHED, &tr->tr_flags);
767f433f 216 if (!list_empty(&bd->bd_list))
192738b7 217 goto out_unlock;
767f433f
SW
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))) {
e54c78a2
BP
222 fs_err(sdp, "Attempting to add uninitialised block to "
223 "journal (inplace block=%lld)\n",
767f433f
SW
224 (unsigned long long)bd->bd_bh->b_blocknr);
225 BUG();
226 }
2e60d768 227 if (unlikely(state == SFS_FROZEN)) {
e54c78a2 228 fs_info(sdp, "GFS2:adding buf while frozen\n");
2e60d768
BM
229 gfs2_assert_withdraw(sdp, 0);
230 }
2ca0c2fb
BP
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 }
767f433f
SW
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);
d69a3c65 238 list_add(&bd->bd_list, &tr->tr_buf);
767f433f 239 tr->tr_num_buf_new++;
192738b7 240out_unlock:
767f433f 241 gfs2_log_unlock(sdp);
aacee720 242out:
767f433f 243 unlock_buffer(bh);
350a9b0a
SW
244}
245
1ad38c43 246void gfs2_trans_add_revoke(struct gfs2_sbd *sdp, struct gfs2_bufdata *bd)
b3b94faa 247{
75f2b879
SW
248 struct gfs2_trans *tr = current->journal_info;
249
c0752aa7 250 BUG_ON(!list_empty(&bd->bd_list));
5d054964 251 gfs2_add_revoke(sdp, bd);
9862ca05 252 set_bit(TR_TOUCHED, &tr->tr_flags);
75f2b879 253 tr->tr_num_revoke++;
b3b94faa
DT
254}
255
fbb27873 256void gfs2_trans_remove_revoke(struct gfs2_sbd *sdp, u64 blkno, unsigned int len)
b3b94faa 257{
5731be53
SW
258 struct gfs2_bufdata *bd, *tmp;
259 struct gfs2_trans *tr = current->journal_info;
260 unsigned int n = len;
b3b94faa
DT
261
262 gfs2_log_lock(sdp);
a5b1d3fc 263 list_for_each_entry_safe(bd, tmp, &sdp->sd_log_revokes, bd_list) {
5731be53 264 if ((bd->bd_blkno >= blkno) && (bd->bd_blkno < (blkno + len))) {
c0752aa7 265 list_del_init(&bd->bd_list);
b3b94faa
DT
266 gfs2_assert_withdraw(sdp, sdp->sd_log_num_revoke);
267 sdp->sd_log_num_revoke--;
fe5e7ba1
BP
268 if (bd->bd_gl)
269 gfs2_glock_remove_revoke(bd->bd_gl);
5731be53 270 kmem_cache_free(gfs2_bufdata_cachep, bd);
a31b4ec5 271 tr->tr_num_revoke_rm++;
5731be53
SW
272 if (--n == 0)
273 break;
b3b94faa
DT
274 }
275 }
b3b94faa 276 gfs2_log_unlock(sdp);
b3b94faa
DT
277}
278