xref: /linux/fs/gfs2/trans.c (revision cc04a46f11ea046ed53e2c832ae29e4790f7e35f)
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 	tr->tr_alloced = 1;
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, tr->tr_touched);
82 	pr_warn("Buf %u/%u Databuf %u/%u Revoke %u/%u\n",
83 		tr->tr_num_buf_new, tr->tr_num_buf_rm,
84 		tr->tr_num_databuf_new, tr->tr_num_databuf_rm,
85 		tr->tr_num_revoke, tr->tr_num_revoke_rm);
86 }
87 
88 void gfs2_trans_end(struct gfs2_sbd *sdp)
89 {
90 	struct gfs2_trans *tr = current->journal_info;
91 	s64 nbuf;
92 	int alloced = tr->tr_alloced;
93 
94 	BUG_ON(!tr);
95 	current->journal_info = NULL;
96 
97 	if (!tr->tr_touched) {
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(tr);
113 
114 	gfs2_log_commit(sdp, tr);
115 	if (alloced && !tr->tr_attached)
116 			kfree(tr);
117 	up_read(&sdp->sd_log_flush_lock);
118 
119 	if (sdp->sd_vfs->s_flags & MS_SYNCHRONOUS)
120 		gfs2_log_flush(sdp, NULL, NORMAL_FLUSH);
121 	if (alloced)
122 		sb_end_intwrite(sdp->sd_vfs);
123 }
124 
125 static struct gfs2_bufdata *gfs2_alloc_bufdata(struct gfs2_glock *gl,
126 					       struct buffer_head *bh,
127 					       const struct gfs2_log_operations *lops)
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 	bd->bd_ops = lops;
135 	INIT_LIST_HEAD(&bd->bd_list);
136 	bh->b_private = bd;
137 	return bd;
138 }
139 
140 /**
141  * gfs2_trans_add_data - Add a databuf to the transaction.
142  * @gl: The inode glock associated with the buffer
143  * @bh: The buffer to add
144  *
145  * This is used in two distinct cases:
146  * i) In ordered write mode
147  *    We put the data buffer on a list so that we can ensure that its
148  *    synced to disk at the right time
149  * ii) In journaled data mode
150  *    We need to journal the data block in the same way as metadata in
151  *    the functions above. The difference is that here we have a tag
152  *    which is two __be64's being the block number (as per meta data)
153  *    and a flag which says whether the data block needs escaping or
154  *    not. This means we need a new log entry for each 251 or so data
155  *    blocks, which isn't an enormous overhead but twice as much as
156  *    for normal metadata blocks.
157  */
158 void gfs2_trans_add_data(struct gfs2_glock *gl, struct buffer_head *bh)
159 {
160 	struct gfs2_trans *tr = current->journal_info;
161 	struct gfs2_sbd *sdp = gl->gl_name.ln_sbd;
162 	struct address_space *mapping = bh->b_page->mapping;
163 	struct gfs2_inode *ip = GFS2_I(mapping->host);
164 	struct gfs2_bufdata *bd;
165 
166 	if (!gfs2_is_jdata(ip)) {
167 		gfs2_ordered_add_inode(ip);
168 		return;
169 	}
170 
171 	lock_buffer(bh);
172 	gfs2_log_lock(sdp);
173 	bd = bh->b_private;
174 	if (bd == NULL) {
175 		gfs2_log_unlock(sdp);
176 		unlock_buffer(bh);
177 		if (bh->b_private == NULL)
178 			bd = gfs2_alloc_bufdata(gl, bh, &gfs2_databuf_lops);
179 		lock_buffer(bh);
180 		gfs2_log_lock(sdp);
181 	}
182 	gfs2_assert(sdp, bd->bd_gl == gl);
183 	tr->tr_touched = 1;
184 	if (list_empty(&bd->bd_list)) {
185 		set_bit(GLF_LFLUSH, &bd->bd_gl->gl_flags);
186 		set_bit(GLF_DIRTY, &bd->bd_gl->gl_flags);
187 		gfs2_pin(sdp, bd->bd_bh);
188 		tr->tr_num_databuf_new++;
189 		list_add_tail(&bd->bd_list, &tr->tr_databuf);
190 	}
191 	gfs2_log_unlock(sdp);
192 	unlock_buffer(bh);
193 }
194 
195 static void meta_lo_add(struct gfs2_sbd *sdp, struct gfs2_bufdata *bd)
196 {
197 	struct gfs2_meta_header *mh;
198 	struct gfs2_trans *tr;
199 	enum gfs2_freeze_state state = atomic_read(&sdp->sd_freeze_state);
200 
201 	tr = current->journal_info;
202 	tr->tr_touched = 1;
203 	if (!list_empty(&bd->bd_list))
204 		return;
205 	set_bit(GLF_LFLUSH, &bd->bd_gl->gl_flags);
206 	set_bit(GLF_DIRTY, &bd->bd_gl->gl_flags);
207 	mh = (struct gfs2_meta_header *)bd->bd_bh->b_data;
208 	if (unlikely(mh->mh_magic != cpu_to_be32(GFS2_MAGIC))) {
209 		pr_err("Attempting to add uninitialised block to journal (inplace block=%lld)\n",
210 		       (unsigned long long)bd->bd_bh->b_blocknr);
211 		BUG();
212 	}
213 	if (unlikely(state == SFS_FROZEN)) {
214 		printk(KERN_INFO "GFS2:adding buf while frozen\n");
215 		gfs2_assert_withdraw(sdp, 0);
216 	}
217 	gfs2_pin(sdp, bd->bd_bh);
218 	mh->__pad0 = cpu_to_be64(0);
219 	mh->mh_jid = cpu_to_be32(sdp->sd_jdesc->jd_jid);
220 	list_add(&bd->bd_list, &tr->tr_buf);
221 	tr->tr_num_buf_new++;
222 }
223 
224 void gfs2_trans_add_meta(struct gfs2_glock *gl, struct buffer_head *bh)
225 {
226 
227 	struct gfs2_sbd *sdp = gl->gl_name.ln_sbd;
228 	struct gfs2_bufdata *bd;
229 
230 	lock_buffer(bh);
231 	gfs2_log_lock(sdp);
232 	bd = bh->b_private;
233 	if (bd == NULL) {
234 		gfs2_log_unlock(sdp);
235 		unlock_buffer(bh);
236 		lock_page(bh->b_page);
237 		if (bh->b_private == NULL)
238 			bd = gfs2_alloc_bufdata(gl, bh, &gfs2_buf_lops);
239 		unlock_page(bh->b_page);
240 		lock_buffer(bh);
241 		gfs2_log_lock(sdp);
242 	}
243 	gfs2_assert(sdp, bd->bd_gl == gl);
244 	meta_lo_add(sdp, bd);
245 	gfs2_log_unlock(sdp);
246 	unlock_buffer(bh);
247 }
248 
249 void gfs2_trans_add_revoke(struct gfs2_sbd *sdp, struct gfs2_bufdata *bd)
250 {
251 	struct gfs2_trans *tr = current->journal_info;
252 
253 	BUG_ON(!list_empty(&bd->bd_list));
254 	gfs2_add_revoke(sdp, bd);
255 	tr->tr_touched = 1;
256 	tr->tr_num_revoke++;
257 }
258 
259 void gfs2_trans_add_unrevoke(struct gfs2_sbd *sdp, u64 blkno, unsigned int len)
260 {
261 	struct gfs2_bufdata *bd, *tmp;
262 	struct gfs2_trans *tr = current->journal_info;
263 	unsigned int n = len;
264 
265 	gfs2_log_lock(sdp);
266 	list_for_each_entry_safe(bd, tmp, &sdp->sd_log_le_revoke, bd_list) {
267 		if ((bd->bd_blkno >= blkno) && (bd->bd_blkno < (blkno + len))) {
268 			list_del_init(&bd->bd_list);
269 			gfs2_assert_withdraw(sdp, sdp->sd_log_num_revoke);
270 			sdp->sd_log_num_revoke--;
271 			kmem_cache_free(gfs2_bufdata_cachep, bd);
272 			tr->tr_num_revoke_rm++;
273 			if (--n == 0)
274 				break;
275 		}
276 	}
277 	gfs2_log_unlock(sdp);
278 }
279 
280