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 #include <linux/sched.h> 11 #include <linux/slab.h> 12 #include <linux/spinlock.h> 13 #include <linux/completion.h> 14 #include <linux/buffer_head.h> 15 #include <linux/kallsyms.h> 16 #include <linux/gfs2_ondisk.h> 17 18 #include "gfs2.h" 19 #include "incore.h" 20 #include "glock.h" 21 #include "log.h" 22 #include "lops.h" 23 #include "meta_io.h" 24 #include "trans.h" 25 #include "util.h" 26 #include "trace_gfs2.h" 27 28 int gfs2_trans_begin(struct gfs2_sbd *sdp, unsigned int blocks, 29 unsigned int revokes) 30 { 31 struct gfs2_trans *tr; 32 int error; 33 34 BUG_ON(current->journal_info); 35 BUG_ON(blocks == 0 && revokes == 0); 36 37 if (!test_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags)) 38 return -EROFS; 39 40 tr = kzalloc(sizeof(struct gfs2_trans), GFP_NOFS); 41 if (!tr) 42 return -ENOMEM; 43 44 tr->tr_ip = (unsigned long)__builtin_return_address(0); 45 tr->tr_blocks = blocks; 46 tr->tr_revokes = revokes; 47 tr->tr_reserved = 1; 48 if (blocks) 49 tr->tr_reserved += 6 + blocks; 50 if (revokes) 51 tr->tr_reserved += gfs2_struct2blk(sdp, revokes, 52 sizeof(u64)); 53 sb_start_intwrite(sdp->sd_vfs); 54 gfs2_holder_init(sdp->sd_trans_gl, LM_ST_SHARED, 0, &tr->tr_t_gh); 55 56 error = gfs2_glock_nq(&tr->tr_t_gh); 57 if (error) 58 goto fail_holder_uninit; 59 60 error = gfs2_log_reserve(sdp, tr->tr_reserved); 61 if (error) 62 goto fail_gunlock; 63 64 current->journal_info = tr; 65 66 return 0; 67 68 fail_gunlock: 69 gfs2_glock_dq(&tr->tr_t_gh); 70 71 fail_holder_uninit: 72 sb_end_intwrite(sdp->sd_vfs); 73 gfs2_holder_uninit(&tr->tr_t_gh); 74 kfree(tr); 75 76 return error; 77 } 78 79 /** 80 * gfs2_log_release - Release a given number of log blocks 81 * @sdp: The GFS2 superblock 82 * @blks: The number of blocks 83 * 84 */ 85 86 static void gfs2_log_release(struct gfs2_sbd *sdp, unsigned int blks) 87 { 88 89 atomic_add(blks, &sdp->sd_log_blks_free); 90 trace_gfs2_log_blocks(sdp, blks); 91 gfs2_assert_withdraw(sdp, atomic_read(&sdp->sd_log_blks_free) <= 92 sdp->sd_jdesc->jd_blocks); 93 up_read(&sdp->sd_log_flush_lock); 94 } 95 96 static void gfs2_print_trans(const struct gfs2_trans *tr) 97 { 98 print_symbol(KERN_WARNING "GFS2: Transaction created at: %s\n", tr->tr_ip); 99 printk(KERN_WARNING "GFS2: blocks=%u revokes=%u reserved=%u touched=%d\n", 100 tr->tr_blocks, tr->tr_revokes, tr->tr_reserved, tr->tr_touched); 101 printk(KERN_WARNING "GFS2: Buf %u/%u Databuf %u/%u Revoke %u/%u\n", 102 tr->tr_num_buf_new, tr->tr_num_buf_rm, 103 tr->tr_num_databuf_new, tr->tr_num_databuf_rm, 104 tr->tr_num_revoke, tr->tr_num_revoke_rm); 105 } 106 107 void gfs2_trans_end(struct gfs2_sbd *sdp) 108 { 109 struct gfs2_trans *tr = current->journal_info; 110 s64 nbuf; 111 BUG_ON(!tr); 112 current->journal_info = NULL; 113 114 if (!tr->tr_touched) { 115 gfs2_log_release(sdp, tr->tr_reserved); 116 if (tr->tr_t_gh.gh_gl) { 117 gfs2_glock_dq(&tr->tr_t_gh); 118 gfs2_holder_uninit(&tr->tr_t_gh); 119 kfree(tr); 120 } 121 sb_end_intwrite(sdp->sd_vfs); 122 return; 123 } 124 125 nbuf = tr->tr_num_buf_new + tr->tr_num_databuf_new; 126 nbuf -= tr->tr_num_buf_rm; 127 nbuf -= tr->tr_num_databuf_rm; 128 129 if (gfs2_assert_withdraw(sdp, (nbuf <= tr->tr_blocks) && 130 (tr->tr_num_revoke <= tr->tr_revokes))) 131 gfs2_print_trans(tr); 132 133 gfs2_log_commit(sdp, tr); 134 if (tr->tr_t_gh.gh_gl) { 135 gfs2_glock_dq(&tr->tr_t_gh); 136 gfs2_holder_uninit(&tr->tr_t_gh); 137 kfree(tr); 138 } 139 140 if (sdp->sd_vfs->s_flags & MS_SYNCHRONOUS) 141 gfs2_log_flush(sdp, NULL); 142 sb_end_intwrite(sdp->sd_vfs); 143 } 144 145 /** 146 * gfs2_trans_add_bh - Add a to-be-modified buffer to the current transaction 147 * @gl: the glock the buffer belongs to 148 * @bh: The buffer to add 149 * @meta: True in the case of adding metadata 150 * 151 */ 152 153 void gfs2_trans_add_bh(struct gfs2_glock *gl, struct buffer_head *bh, int meta) 154 { 155 struct gfs2_sbd *sdp = gl->gl_sbd; 156 struct gfs2_bufdata *bd; 157 158 lock_buffer(bh); 159 gfs2_log_lock(sdp); 160 bd = bh->b_private; 161 if (bd) 162 gfs2_assert(sdp, bd->bd_gl == gl); 163 else { 164 gfs2_log_unlock(sdp); 165 unlock_buffer(bh); 166 gfs2_attach_bufdata(gl, bh, meta); 167 bd = bh->b_private; 168 lock_buffer(bh); 169 gfs2_log_lock(sdp); 170 } 171 lops_add(sdp, bd); 172 gfs2_log_unlock(sdp); 173 unlock_buffer(bh); 174 } 175 176 void gfs2_trans_add_revoke(struct gfs2_sbd *sdp, struct gfs2_bufdata *bd) 177 { 178 BUG_ON(!list_empty(&bd->bd_list)); 179 BUG_ON(!list_empty(&bd->bd_ail_st_list)); 180 BUG_ON(!list_empty(&bd->bd_ail_gl_list)); 181 lops_init_le(bd, &gfs2_revoke_lops); 182 lops_add(sdp, bd); 183 } 184 185 void gfs2_trans_add_unrevoke(struct gfs2_sbd *sdp, u64 blkno, unsigned int len) 186 { 187 struct gfs2_bufdata *bd, *tmp; 188 struct gfs2_trans *tr = current->journal_info; 189 unsigned int n = len; 190 191 gfs2_log_lock(sdp); 192 list_for_each_entry_safe(bd, tmp, &sdp->sd_log_le_revoke, bd_list) { 193 if ((bd->bd_blkno >= blkno) && (bd->bd_blkno < (blkno + len))) { 194 list_del_init(&bd->bd_list); 195 gfs2_assert_withdraw(sdp, sdp->sd_log_num_revoke); 196 sdp->sd_log_num_revoke--; 197 kmem_cache_free(gfs2_bufdata_cachep, bd); 198 tr->tr_num_revoke_rm++; 199 if (--n == 0) 200 break; 201 } 202 } 203 gfs2_log_unlock(sdp); 204 } 205 206