xref: /linux/fs/gfs2/trans.c (revision fd639726bf15fca8ee1a00dce8e0096d0ad9bd18)
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(const struct gfs2_trans *tr)
78 {
79 	pr_warn("Transaction created at: %pSR\n", (void *)tr->tr_ip);
80 	pr_warn("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 	pr_warn("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 	BUG_ON(!tr);
96 	current->journal_info = NULL;
97 
98 	if (!test_bit(TR_TOUCHED, &tr->tr_flags)) {
99 		gfs2_log_release(sdp, tr->tr_reserved);
100 		if (alloced) {
101 			kfree(tr);
102 			sb_end_intwrite(sdp->sd_vfs);
103 		}
104 		return;
105 	}
106 
107 	nbuf = tr->tr_num_buf_new + tr->tr_num_databuf_new;
108 	nbuf -= tr->tr_num_buf_rm;
109 	nbuf -= tr->tr_num_databuf_rm;
110 
111 	if (gfs2_assert_withdraw(sdp, (nbuf <= tr->tr_blocks) &&
112 				       (tr->tr_num_revoke <= tr->tr_revokes)))
113 		gfs2_print_trans(tr);
114 
115 	gfs2_log_commit(sdp, tr);
116 	if (alloced && !test_bit(TR_ATTACHED, &tr->tr_flags))
117 		kfree(tr);
118 	up_read(&sdp->sd_log_flush_lock);
119 
120 	if (sdp->sd_vfs->s_flags & SB_SYNCHRONOUS)
121 		gfs2_log_flush(sdp, NULL, NORMAL_FLUSH);
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 					       const struct gfs2_log_operations *lops)
129 {
130 	struct gfs2_bufdata *bd;
131 
132 	bd = kmem_cache_zalloc(gfs2_bufdata_cachep, GFP_NOFS | __GFP_NOFAIL);
133 	bd->bd_bh = bh;
134 	bd->bd_gl = gl;
135 	bd->bd_ops = lops;
136 	INIT_LIST_HEAD(&bd->bd_list);
137 	bh->b_private = bd;
138 	return bd;
139 }
140 
141 /**
142  * gfs2_trans_add_data - Add a databuf to the transaction.
143  * @gl: The inode glock associated with the buffer
144  * @bh: The buffer to add
145  *
146  * This is used in two distinct cases:
147  * i) In ordered write mode
148  *    We put the data buffer on a list so that we can ensure that it's
149  *    synced to disk at the right time
150  * ii) In journaled data mode
151  *    We need to journal the data block in the same way as metadata in
152  *    the functions above. The difference is that here we have a tag
153  *    which is two __be64's being the block number (as per meta data)
154  *    and a flag which says whether the data block needs escaping or
155  *    not. This means we need a new log entry for each 251 or so data
156  *    blocks, which isn't an enormous overhead but twice as much as
157  *    for normal metadata blocks.
158  */
159 void gfs2_trans_add_data(struct gfs2_glock *gl, struct buffer_head *bh)
160 {
161 	struct gfs2_trans *tr = current->journal_info;
162 	struct gfs2_sbd *sdp = gl->gl_name.ln_sbd;
163 	struct address_space *mapping = bh->b_page->mapping;
164 	struct gfs2_inode *ip = GFS2_I(mapping->host);
165 	struct gfs2_bufdata *bd;
166 
167 	if (!gfs2_is_jdata(ip)) {
168 		gfs2_ordered_add_inode(ip);
169 		return;
170 	}
171 
172 	lock_buffer(bh);
173 	if (buffer_pinned(bh)) {
174 		set_bit(TR_TOUCHED, &tr->tr_flags);
175 		goto out;
176 	}
177 	gfs2_log_lock(sdp);
178 	bd = bh->b_private;
179 	if (bd == NULL) {
180 		gfs2_log_unlock(sdp);
181 		unlock_buffer(bh);
182 		if (bh->b_private == NULL)
183 			bd = gfs2_alloc_bufdata(gl, bh, &gfs2_databuf_lops);
184 		else
185 			bd = bh->b_private;
186 		lock_buffer(bh);
187 		gfs2_log_lock(sdp);
188 	}
189 	gfs2_assert(sdp, bd->bd_gl == gl);
190 	set_bit(TR_TOUCHED, &tr->tr_flags);
191 	if (list_empty(&bd->bd_list)) {
192 		set_bit(GLF_LFLUSH, &bd->bd_gl->gl_flags);
193 		set_bit(GLF_DIRTY, &bd->bd_gl->gl_flags);
194 		gfs2_pin(sdp, bd->bd_bh);
195 		tr->tr_num_databuf_new++;
196 		list_add_tail(&bd->bd_list, &tr->tr_databuf);
197 	}
198 	gfs2_log_unlock(sdp);
199 out:
200 	unlock_buffer(bh);
201 }
202 
203 void gfs2_trans_add_meta(struct gfs2_glock *gl, struct buffer_head *bh)
204 {
205 
206 	struct gfs2_sbd *sdp = gl->gl_name.ln_sbd;
207 	struct gfs2_bufdata *bd;
208 	struct gfs2_meta_header *mh;
209 	struct gfs2_trans *tr = current->journal_info;
210 	enum gfs2_freeze_state state = atomic_read(&sdp->sd_freeze_state);
211 
212 	lock_buffer(bh);
213 	if (buffer_pinned(bh)) {
214 		set_bit(TR_TOUCHED, &tr->tr_flags);
215 		goto out;
216 	}
217 	gfs2_log_lock(sdp);
218 	bd = bh->b_private;
219 	if (bd == NULL) {
220 		gfs2_log_unlock(sdp);
221 		unlock_buffer(bh);
222 		lock_page(bh->b_page);
223 		if (bh->b_private == NULL)
224 			bd = gfs2_alloc_bufdata(gl, bh, &gfs2_buf_lops);
225 		else
226 			bd = bh->b_private;
227 		unlock_page(bh->b_page);
228 		lock_buffer(bh);
229 		gfs2_log_lock(sdp);
230 	}
231 	gfs2_assert(sdp, bd->bd_gl == gl);
232 	set_bit(TR_TOUCHED, &tr->tr_flags);
233 	if (!list_empty(&bd->bd_list))
234 		goto out_unlock;
235 	set_bit(GLF_LFLUSH, &bd->bd_gl->gl_flags);
236 	set_bit(GLF_DIRTY, &bd->bd_gl->gl_flags);
237 	mh = (struct gfs2_meta_header *)bd->bd_bh->b_data;
238 	if (unlikely(mh->mh_magic != cpu_to_be32(GFS2_MAGIC))) {
239 		pr_err("Attempting to add uninitialised block to journal (inplace block=%lld)\n",
240 		       (unsigned long long)bd->bd_bh->b_blocknr);
241 		BUG();
242 	}
243 	if (unlikely(state == SFS_FROZEN)) {
244 		printk(KERN_INFO "GFS2:adding buf while frozen\n");
245 		gfs2_assert_withdraw(sdp, 0);
246 	}
247 	gfs2_pin(sdp, bd->bd_bh);
248 	mh->__pad0 = cpu_to_be64(0);
249 	mh->mh_jid = cpu_to_be32(sdp->sd_jdesc->jd_jid);
250 	list_add(&bd->bd_list, &tr->tr_buf);
251 	tr->tr_num_buf_new++;
252 out_unlock:
253 	gfs2_log_unlock(sdp);
254 out:
255 	unlock_buffer(bh);
256 }
257 
258 void gfs2_trans_add_revoke(struct gfs2_sbd *sdp, struct gfs2_bufdata *bd)
259 {
260 	struct gfs2_trans *tr = current->journal_info;
261 
262 	BUG_ON(!list_empty(&bd->bd_list));
263 	gfs2_add_revoke(sdp, bd);
264 	set_bit(TR_TOUCHED, &tr->tr_flags);
265 	tr->tr_num_revoke++;
266 }
267 
268 void gfs2_trans_add_unrevoke(struct gfs2_sbd *sdp, u64 blkno, unsigned int len)
269 {
270 	struct gfs2_bufdata *bd, *tmp;
271 	struct gfs2_trans *tr = current->journal_info;
272 	unsigned int n = len;
273 
274 	gfs2_log_lock(sdp);
275 	list_for_each_entry_safe(bd, tmp, &sdp->sd_log_le_revoke, bd_list) {
276 		if ((bd->bd_blkno >= blkno) && (bd->bd_blkno < (blkno + len))) {
277 			list_del_init(&bd->bd_list);
278 			gfs2_assert_withdraw(sdp, sdp->sd_log_num_revoke);
279 			sdp->sd_log_num_revoke--;
280 			kmem_cache_free(gfs2_bufdata_cachep, bd);
281 			tr->tr_num_revoke_rm++;
282 			if (--n == 0)
283 				break;
284 		}
285 	}
286 	gfs2_log_unlock(sdp);
287 }
288 
289