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 = (unsigned long)__builtin_return_address(0); 48 tr->tr_blocks = blocks; 49 tr->tr_revokes = revokes; 50 tr->tr_reserved = 1; 51 if (blocks) 52 tr->tr_reserved += 6 + blocks; 53 if (revokes) 54 tr->tr_reserved += gfs2_struct2blk(sdp, revokes, 55 sizeof(u64)); 56 INIT_LIST_HEAD(&tr->tr_databuf); 57 INIT_LIST_HEAD(&tr->tr_buf); 58 59 sb_start_intwrite(sdp->sd_vfs); 60 gfs2_holder_init(sdp->sd_trans_gl, LM_ST_SHARED, 0, &tr->tr_t_gh); 61 62 error = gfs2_glock_nq(&tr->tr_t_gh); 63 if (error) 64 goto fail_holder_uninit; 65 66 error = gfs2_log_reserve(sdp, tr->tr_reserved); 67 if (error) 68 goto fail_gunlock; 69 70 current->journal_info = tr; 71 72 return 0; 73 74 fail_gunlock: 75 gfs2_glock_dq(&tr->tr_t_gh); 76 77 fail_holder_uninit: 78 sb_end_intwrite(sdp->sd_vfs); 79 gfs2_holder_uninit(&tr->tr_t_gh); 80 kfree(tr); 81 82 return error; 83 } 84 85 /** 86 * gfs2_log_release - Release a given number of log blocks 87 * @sdp: The GFS2 superblock 88 * @blks: The number of blocks 89 * 90 */ 91 92 static void gfs2_log_release(struct gfs2_sbd *sdp, unsigned int blks) 93 { 94 95 atomic_add(blks, &sdp->sd_log_blks_free); 96 trace_gfs2_log_blocks(sdp, blks); 97 gfs2_assert_withdraw(sdp, atomic_read(&sdp->sd_log_blks_free) <= 98 sdp->sd_jdesc->jd_blocks); 99 up_read(&sdp->sd_log_flush_lock); 100 } 101 102 static void gfs2_print_trans(const struct gfs2_trans *tr) 103 { 104 pr_warn("Transaction created at: %pSR\n", (void *)tr->tr_ip); 105 pr_warn("blocks=%u revokes=%u reserved=%u touched=%u\n", 106 tr->tr_blocks, tr->tr_revokes, tr->tr_reserved, tr->tr_touched); 107 pr_warn("Buf %u/%u Databuf %u/%u Revoke %u/%u\n", 108 tr->tr_num_buf_new, tr->tr_num_buf_rm, 109 tr->tr_num_databuf_new, tr->tr_num_databuf_rm, 110 tr->tr_num_revoke, tr->tr_num_revoke_rm); 111 } 112 113 void gfs2_trans_end(struct gfs2_sbd *sdp) 114 { 115 struct gfs2_trans *tr = current->journal_info; 116 s64 nbuf; 117 BUG_ON(!tr); 118 current->journal_info = NULL; 119 120 if (!tr->tr_touched) { 121 gfs2_log_release(sdp, tr->tr_reserved); 122 if (tr->tr_t_gh.gh_gl) { 123 gfs2_glock_dq(&tr->tr_t_gh); 124 gfs2_holder_uninit(&tr->tr_t_gh); 125 kfree(tr); 126 } 127 sb_end_intwrite(sdp->sd_vfs); 128 return; 129 } 130 131 nbuf = tr->tr_num_buf_new + tr->tr_num_databuf_new; 132 nbuf -= tr->tr_num_buf_rm; 133 nbuf -= tr->tr_num_databuf_rm; 134 135 if (gfs2_assert_withdraw(sdp, (nbuf <= tr->tr_blocks) && 136 (tr->tr_num_revoke <= tr->tr_revokes))) 137 gfs2_print_trans(tr); 138 139 gfs2_log_commit(sdp, tr); 140 if (tr->tr_t_gh.gh_gl) { 141 gfs2_glock_dq(&tr->tr_t_gh); 142 gfs2_holder_uninit(&tr->tr_t_gh); 143 if (!tr->tr_attached) 144 kfree(tr); 145 } 146 up_read(&sdp->sd_log_flush_lock); 147 148 if (sdp->sd_vfs->s_flags & MS_SYNCHRONOUS) 149 gfs2_log_flush(sdp, NULL); 150 sb_end_intwrite(sdp->sd_vfs); 151 } 152 153 static struct gfs2_bufdata *gfs2_alloc_bufdata(struct gfs2_glock *gl, 154 struct buffer_head *bh, 155 const struct gfs2_log_operations *lops) 156 { 157 struct gfs2_bufdata *bd; 158 159 bd = kmem_cache_zalloc(gfs2_bufdata_cachep, GFP_NOFS | __GFP_NOFAIL); 160 bd->bd_bh = bh; 161 bd->bd_gl = gl; 162 bd->bd_ops = lops; 163 INIT_LIST_HEAD(&bd->bd_list); 164 bh->b_private = bd; 165 return bd; 166 } 167 168 /** 169 * gfs2_trans_add_data - Add a databuf to the transaction. 170 * @gl: The inode glock associated with the buffer 171 * @bh: The buffer to add 172 * 173 * This is used in two distinct cases: 174 * i) In ordered write mode 175 * We put the data buffer on a list so that we can ensure that its 176 * synced to disk at the right time 177 * ii) In journaled data mode 178 * We need to journal the data block in the same way as metadata in 179 * the functions above. The difference is that here we have a tag 180 * which is two __be64's being the block number (as per meta data) 181 * and a flag which says whether the data block needs escaping or 182 * not. This means we need a new log entry for each 251 or so data 183 * blocks, which isn't an enormous overhead but twice as much as 184 * for normal metadata blocks. 185 */ 186 void gfs2_trans_add_data(struct gfs2_glock *gl, struct buffer_head *bh) 187 { 188 struct gfs2_trans *tr = current->journal_info; 189 struct gfs2_sbd *sdp = gl->gl_sbd; 190 struct address_space *mapping = bh->b_page->mapping; 191 struct gfs2_inode *ip = GFS2_I(mapping->host); 192 struct gfs2_bufdata *bd; 193 194 if (!gfs2_is_jdata(ip)) { 195 gfs2_ordered_add_inode(ip); 196 return; 197 } 198 199 lock_buffer(bh); 200 gfs2_log_lock(sdp); 201 bd = bh->b_private; 202 if (bd == NULL) { 203 gfs2_log_unlock(sdp); 204 unlock_buffer(bh); 205 if (bh->b_private == NULL) 206 bd = gfs2_alloc_bufdata(gl, bh, &gfs2_databuf_lops); 207 lock_buffer(bh); 208 gfs2_log_lock(sdp); 209 } 210 gfs2_assert(sdp, bd->bd_gl == gl); 211 tr->tr_touched = 1; 212 if (list_empty(&bd->bd_list)) { 213 set_bit(GLF_LFLUSH, &bd->bd_gl->gl_flags); 214 set_bit(GLF_DIRTY, &bd->bd_gl->gl_flags); 215 gfs2_pin(sdp, bd->bd_bh); 216 tr->tr_num_databuf_new++; 217 list_add_tail(&bd->bd_list, &tr->tr_databuf); 218 } 219 gfs2_log_unlock(sdp); 220 unlock_buffer(bh); 221 } 222 223 static void meta_lo_add(struct gfs2_sbd *sdp, struct gfs2_bufdata *bd) 224 { 225 struct gfs2_meta_header *mh; 226 struct gfs2_trans *tr; 227 228 tr = current->journal_info; 229 tr->tr_touched = 1; 230 if (!list_empty(&bd->bd_list)) 231 return; 232 set_bit(GLF_LFLUSH, &bd->bd_gl->gl_flags); 233 set_bit(GLF_DIRTY, &bd->bd_gl->gl_flags); 234 mh = (struct gfs2_meta_header *)bd->bd_bh->b_data; 235 if (unlikely(mh->mh_magic != cpu_to_be32(GFS2_MAGIC))) { 236 pr_err("Attempting to add uninitialised block to journal (inplace block=%lld)\n", 237 (unsigned long long)bd->bd_bh->b_blocknr); 238 BUG(); 239 } 240 gfs2_pin(sdp, bd->bd_bh); 241 mh->__pad0 = cpu_to_be64(0); 242 mh->mh_jid = cpu_to_be32(sdp->sd_jdesc->jd_jid); 243 list_add(&bd->bd_list, &tr->tr_buf); 244 tr->tr_num_buf_new++; 245 } 246 247 void gfs2_trans_add_meta(struct gfs2_glock *gl, struct buffer_head *bh) 248 { 249 250 struct gfs2_sbd *sdp = gl->gl_sbd; 251 struct gfs2_bufdata *bd; 252 253 lock_buffer(bh); 254 gfs2_log_lock(sdp); 255 bd = bh->b_private; 256 if (bd == NULL) { 257 gfs2_log_unlock(sdp); 258 unlock_buffer(bh); 259 lock_page(bh->b_page); 260 if (bh->b_private == NULL) 261 bd = gfs2_alloc_bufdata(gl, bh, &gfs2_buf_lops); 262 unlock_page(bh->b_page); 263 lock_buffer(bh); 264 gfs2_log_lock(sdp); 265 } 266 gfs2_assert(sdp, bd->bd_gl == gl); 267 meta_lo_add(sdp, bd); 268 gfs2_log_unlock(sdp); 269 unlock_buffer(bh); 270 } 271 272 void gfs2_trans_add_revoke(struct gfs2_sbd *sdp, struct gfs2_bufdata *bd) 273 { 274 struct gfs2_trans *tr = current->journal_info; 275 276 BUG_ON(!list_empty(&bd->bd_list)); 277 gfs2_add_revoke(sdp, bd); 278 tr->tr_touched = 1; 279 tr->tr_num_revoke++; 280 } 281 282 void gfs2_trans_add_unrevoke(struct gfs2_sbd *sdp, u64 blkno, unsigned int len) 283 { 284 struct gfs2_bufdata *bd, *tmp; 285 struct gfs2_trans *tr = current->journal_info; 286 unsigned int n = len; 287 288 gfs2_log_lock(sdp); 289 list_for_each_entry_safe(bd, tmp, &sdp->sd_log_le_revoke, bd_list) { 290 if ((bd->bd_blkno >= blkno) && (bd->bd_blkno < (blkno + len))) { 291 list_del_init(&bd->bd_list); 292 gfs2_assert_withdraw(sdp, sdp->sd_log_num_revoke); 293 sdp->sd_log_num_revoke--; 294 kmem_cache_free(gfs2_bufdata_cachep, bd); 295 tr->tr_num_revoke_rm++; 296 if (--n == 0) 297 break; 298 } 299 } 300 gfs2_log_unlock(sdp); 301 } 302 303