xref: /linux/fs/gfs2/trans.c (revision 4e0ae876f77bc01a7e77724dea57b4b82bd53244)
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 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
11 
12 #include <linux/sched.h>
13 #include <linux/slab.h>
14 #include <linux/spinlock.h>
15 #include <linux/completion.h>
16 #include <linux/buffer_head.h>
17 #include <linux/kallsyms.h>
18 #include <linux/gfs2_ondisk.h>
19 
20 #include "gfs2.h"
21 #include "incore.h"
22 #include "glock.h"
23 #include "inode.h"
24 #include "log.h"
25 #include "lops.h"
26 #include "meta_io.h"
27 #include "trans.h"
28 #include "util.h"
29 #include "trace_gfs2.h"
30 
31 int gfs2_trans_begin(struct gfs2_sbd *sdp, unsigned int blocks,
32 		     unsigned int revokes)
33 {
34 	struct gfs2_trans *tr;
35 	int error;
36 
37 	BUG_ON(current->journal_info);
38 	BUG_ON(blocks == 0 && revokes == 0);
39 
40 	if (!test_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags))
41 		return -EROFS;
42 
43 	tr = kzalloc(sizeof(struct gfs2_trans), GFP_NOFS);
44 	if (!tr)
45 		return -ENOMEM;
46 
47 	tr->tr_ip = _RET_IP_;
48 	tr->tr_blocks = blocks;
49 	tr->tr_revokes = revokes;
50 	tr->tr_reserved = 1;
51 	set_bit(TR_ALLOCED, &tr->tr_flags);
52 	if (blocks)
53 		tr->tr_reserved += 6 + blocks;
54 	if (revokes)
55 		tr->tr_reserved += gfs2_struct2blk(sdp, revokes,
56 						   sizeof(u64));
57 	INIT_LIST_HEAD(&tr->tr_databuf);
58 	INIT_LIST_HEAD(&tr->tr_buf);
59 
60 	sb_start_intwrite(sdp->sd_vfs);
61 
62 	error = gfs2_log_reserve(sdp, tr->tr_reserved);
63 	if (error)
64 		goto fail;
65 
66 	current->journal_info = tr;
67 
68 	return 0;
69 
70 fail:
71 	sb_end_intwrite(sdp->sd_vfs);
72 	kfree(tr);
73 
74 	return error;
75 }
76 
77 static void gfs2_print_trans(struct gfs2_sbd *sdp, const struct gfs2_trans *tr)
78 {
79 	fs_warn(sdp, "Transaction created at: %pSR\n", (void *)tr->tr_ip);
80 	fs_warn(sdp, "blocks=%u revokes=%u reserved=%u touched=%u\n",
81 		tr->tr_blocks, tr->tr_revokes, tr->tr_reserved,
82 		test_bit(TR_TOUCHED, &tr->tr_flags));
83 	fs_warn(sdp, "Buf %u/%u Databuf %u/%u Revoke %u/%u\n",
84 		tr->tr_num_buf_new, tr->tr_num_buf_rm,
85 		tr->tr_num_databuf_new, tr->tr_num_databuf_rm,
86 		tr->tr_num_revoke, tr->tr_num_revoke_rm);
87 }
88 
89 void gfs2_trans_end(struct gfs2_sbd *sdp)
90 {
91 	struct gfs2_trans *tr = current->journal_info;
92 	s64 nbuf;
93 	int alloced = test_bit(TR_ALLOCED, &tr->tr_flags);
94 
95 	current->journal_info = NULL;
96 
97 	if (!test_bit(TR_TOUCHED, &tr->tr_flags)) {
98 		gfs2_log_release(sdp, tr->tr_reserved);
99 		if (alloced) {
100 			kfree(tr);
101 			sb_end_intwrite(sdp->sd_vfs);
102 		}
103 		return;
104 	}
105 
106 	nbuf = tr->tr_num_buf_new + tr->tr_num_databuf_new;
107 	nbuf -= tr->tr_num_buf_rm;
108 	nbuf -= tr->tr_num_databuf_rm;
109 
110 	if (gfs2_assert_withdraw(sdp, (nbuf <= tr->tr_blocks) &&
111 				       (tr->tr_num_revoke <= tr->tr_revokes)))
112 		gfs2_print_trans(sdp, tr);
113 
114 	gfs2_log_commit(sdp, tr);
115 	if (alloced && !test_bit(TR_ATTACHED, &tr->tr_flags))
116 		kfree(tr);
117 	up_read(&sdp->sd_log_flush_lock);
118 
119 	if (sdp->sd_vfs->s_flags & SB_SYNCHRONOUS)
120 		gfs2_log_flush(sdp, NULL, GFS2_LOG_HEAD_FLUSH_NORMAL |
121 			       GFS2_LFC_TRANS_END);
122 	if (alloced)
123 		sb_end_intwrite(sdp->sd_vfs);
124 }
125 
126 static struct gfs2_bufdata *gfs2_alloc_bufdata(struct gfs2_glock *gl,
127 					       struct buffer_head *bh)
128 {
129 	struct gfs2_bufdata *bd;
130 
131 	bd = kmem_cache_zalloc(gfs2_bufdata_cachep, GFP_NOFS | __GFP_NOFAIL);
132 	bd->bd_bh = bh;
133 	bd->bd_gl = gl;
134 	INIT_LIST_HEAD(&bd->bd_list);
135 	bh->b_private = bd;
136 	return bd;
137 }
138 
139 /**
140  * gfs2_trans_add_data - Add a databuf to the transaction.
141  * @gl: The inode glock associated with the buffer
142  * @bh: The buffer to add
143  *
144  * This is used in journaled data mode.
145  * We need to journal the data block in the same way as metadata in
146  * the functions above. The difference is that here we have a tag
147  * which is two __be64's being the block number (as per meta data)
148  * and a flag which says whether the data block needs escaping or
149  * not. This means we need a new log entry for each 251 or so data
150  * blocks, which isn't an enormous overhead but twice as much as
151  * for normal metadata blocks.
152  */
153 void gfs2_trans_add_data(struct gfs2_glock *gl, struct buffer_head *bh)
154 {
155 	struct gfs2_trans *tr = current->journal_info;
156 	struct gfs2_sbd *sdp = gl->gl_name.ln_sbd;
157 	struct gfs2_bufdata *bd;
158 
159 	lock_buffer(bh);
160 	if (buffer_pinned(bh)) {
161 		set_bit(TR_TOUCHED, &tr->tr_flags);
162 		goto out;
163 	}
164 	gfs2_log_lock(sdp);
165 	bd = bh->b_private;
166 	if (bd == NULL) {
167 		gfs2_log_unlock(sdp);
168 		unlock_buffer(bh);
169 		if (bh->b_private == NULL)
170 			bd = gfs2_alloc_bufdata(gl, bh);
171 		else
172 			bd = bh->b_private;
173 		lock_buffer(bh);
174 		gfs2_log_lock(sdp);
175 	}
176 	gfs2_assert(sdp, bd->bd_gl == gl);
177 	set_bit(TR_TOUCHED, &tr->tr_flags);
178 	if (list_empty(&bd->bd_list)) {
179 		set_bit(GLF_LFLUSH, &bd->bd_gl->gl_flags);
180 		set_bit(GLF_DIRTY, &bd->bd_gl->gl_flags);
181 		gfs2_pin(sdp, bd->bd_bh);
182 		tr->tr_num_databuf_new++;
183 		list_add_tail(&bd->bd_list, &tr->tr_databuf);
184 	}
185 	gfs2_log_unlock(sdp);
186 out:
187 	unlock_buffer(bh);
188 }
189 
190 void gfs2_trans_add_meta(struct gfs2_glock *gl, struct buffer_head *bh)
191 {
192 
193 	struct gfs2_sbd *sdp = gl->gl_name.ln_sbd;
194 	struct gfs2_bufdata *bd;
195 	struct gfs2_meta_header *mh;
196 	struct gfs2_trans *tr = current->journal_info;
197 	enum gfs2_freeze_state state = atomic_read(&sdp->sd_freeze_state);
198 
199 	lock_buffer(bh);
200 	if (buffer_pinned(bh)) {
201 		set_bit(TR_TOUCHED, &tr->tr_flags);
202 		goto out;
203 	}
204 	gfs2_log_lock(sdp);
205 	bd = bh->b_private;
206 	if (bd == NULL) {
207 		gfs2_log_unlock(sdp);
208 		unlock_buffer(bh);
209 		lock_page(bh->b_page);
210 		if (bh->b_private == NULL)
211 			bd = gfs2_alloc_bufdata(gl, bh);
212 		else
213 			bd = bh->b_private;
214 		unlock_page(bh->b_page);
215 		lock_buffer(bh);
216 		gfs2_log_lock(sdp);
217 	}
218 	gfs2_assert(sdp, bd->bd_gl == gl);
219 	set_bit(TR_TOUCHED, &tr->tr_flags);
220 	if (!list_empty(&bd->bd_list))
221 		goto out_unlock;
222 	set_bit(GLF_LFLUSH, &bd->bd_gl->gl_flags);
223 	set_bit(GLF_DIRTY, &bd->bd_gl->gl_flags);
224 	mh = (struct gfs2_meta_header *)bd->bd_bh->b_data;
225 	if (unlikely(mh->mh_magic != cpu_to_be32(GFS2_MAGIC))) {
226 		fs_err(sdp, "Attempting to add uninitialised block to "
227 		       "journal (inplace block=%lld)\n",
228 		       (unsigned long long)bd->bd_bh->b_blocknr);
229 		BUG();
230 	}
231 	if (unlikely(state == SFS_FROZEN)) {
232 		fs_info(sdp, "GFS2:adding buf while frozen\n");
233 		gfs2_assert_withdraw(sdp, 0);
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_add_unrevoke(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_le_revoke, 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 			kmem_cache_free(gfs2_bufdata_cachep, bd);
269 			tr->tr_num_revoke_rm++;
270 			if (--n == 0)
271 				break;
272 		}
273 	}
274 	gfs2_log_unlock(sdp);
275 }
276 
277