fs/quota/quota_v2.c

   1 /*
   2  *      vfsv0 quota IO operations on file
   3  */
   4
   5 #include <linux/errno.h>
   6 #include <linux/fs.h>
   7 #include <linux/mount.h>
   8 #include <linux/dqblk_v2.h>
   9 #include <linux/kernel.h>
  10 #include <linux/init.h>
  11 #include <linux/module.h>
  12 #include <linux/slab.h>
  13 #include <linux/quotaops.h>
  14
  15 #include <asm/byteorder.h>
  16
  17 #include "quota_tree.h"
  18 #include "quotaio_v2.h"
  19
  20 MODULE_AUTHOR("Jan Kara");
  21 MODULE_DESCRIPTION("Quota format v2 support");
  22 MODULE_LICENSE("GPL");
  23
  24 #define __QUOTA_V2_PARANOIA
  25
  26 static void v2r0_mem2diskdqb(void *dp, struct dquot *dquot);
  27 static void v2r0_disk2memdqb(struct dquot *dquot, void *dp);
  28 static int v2r0_is_id(void *dp, struct dquot *dquot);
  29 static void v2r1_mem2diskdqb(void *dp, struct dquot *dquot);
  30 static void v2r1_disk2memdqb(struct dquot *dquot, void *dp);
  31 static int v2r1_is_id(void *dp, struct dquot *dquot);
  32
  33 static struct qtree_fmt_operations v2r0_qtree_ops = {
  34         .mem2disk_dqblk = v2r0_mem2diskdqb,
  35         .disk2mem_dqblk = v2r0_disk2memdqb,
  36         .is_id = v2r0_is_id,
  37 };
  38
  39 static struct qtree_fmt_operations v2r1_qtree_ops = {
  40         .mem2disk_dqblk = v2r1_mem2diskdqb,
  41         .disk2mem_dqblk = v2r1_disk2memdqb,
  42         .is_id = v2r1_is_id,
  43 };
  44
  45 #define QUOTABLOCK_BITS 10
  46 #define QUOTABLOCK_SIZE (1 << QUOTABLOCK_BITS)
  47
  48 static inline qsize_t v2_stoqb(qsize_t space)
  49 {
  50         return (space + QUOTABLOCK_SIZE - 1) >> QUOTABLOCK_BITS;
  51 }
  52
  53 static inline qsize_t v2_qbtos(qsize_t blocks)
  54 {
  55         return blocks << QUOTABLOCK_BITS;
  56 }
  57
  58 static int v2_read_header(struct super_block *sb, int type,
  59                           struct v2_disk_dqheader *dqhead)
  60 {
  61         ssize_t size;
  62
  63         size = sb->s_op->quota_read(sb, type, (char *)dqhead,
  64                                     sizeof(struct v2_disk_dqheader), 0);
  65         if (size != sizeof(struct v2_disk_dqheader)) {
  66                 q_warn(KERN_WARNING "quota_v2: Failed header read:"
  67                        " expected=%zd got=%zd\n",
  68                         sizeof(struct v2_disk_dqheader), size);
  69                 return 0;
  70         }
  71         return 1;
  72 }
  73
  74 /* Check whether given file is really vfsv0 quotafile */
  75 static int v2_check_quota_file(struct super_block *sb, int type)
  76 {
  77         struct v2_disk_dqheader dqhead;
  78         static const uint quota_magics[] = V2_INITQMAGICS;
  79         static const uint quota_versions[] = V2_INITQVERSIONS;
  80
  81         if (!v2_read_header(sb, type, &dqhead))
  82                 return 0;
  83         if (le32_to_cpu(dqhead.dqh_magic) != quota_magics[type] ||
  84             le32_to_cpu(dqhead.dqh_version) > quota_versions[type])
  85                 return 0;
  86         return 1;
  87 }
  88
  89 /* Read information header from quota file */
  90 static int v2_read_file_info(struct super_block *sb, int type)
  91 {
  92         struct v2_disk_dqinfo dinfo;
  93         struct v2_disk_dqheader dqhead;
  94         struct mem_dqinfo *info = sb_dqinfo(sb, type);
  95         struct qtree_mem_dqinfo *qinfo;
  96         ssize_t size;
  97         unsigned int version;
  98
  99         if (!v2_read_header(sb, type, &dqhead))
 100                 return -1;
 101         version = le32_to_cpu(dqhead.dqh_version);
 102         if ((info->dqi_fmt_id == QFMT_VFS_V0 && version != 0) ||
 103             (info->dqi_fmt_id == QFMT_VFS_V1 && version != 1))
 104                 return -1;
 105
 106         size = sb->s_op->quota_read(sb, type, (char *)&dinfo,
 107                sizeof(struct v2_disk_dqinfo), V2_DQINFOOFF);
 108         if (size != sizeof(struct v2_disk_dqinfo)) {
 109                 q_warn(KERN_WARNING "quota_v2: Can't read info structure on device %s.\n",
 110                         sb->s_id);
 111                 return -1;
 112         }
 113         info->dqi_priv = kmalloc(sizeof(struct qtree_mem_dqinfo), GFP_NOFS);
 114         if (!info->dqi_priv) {
 115                 printk(KERN_WARNING
 116                        "Not enough memory for quota information structure.\n");
 117                 return -1;
 118         }
 119         qinfo = info->dqi_priv;
 120         if (version == 0) {
 121                 /* limits are stored as unsigned 32-bit data */
 122                 info->dqi_maxblimit = 0xffffffff;
 123                 info->dqi_maxilimit = 0xffffffff;
 124         } else {
 125                 /* used space is stored as unsigned 64-bit value */
 126                 info->dqi_maxblimit = 0xffffffffffffffffULL;    /* 2^64-1 */
 127                 info->dqi_maxilimit = 0xffffffffffffffffULL;
 128         }
 129         info->dqi_bgrace = le32_to_cpu(dinfo.dqi_bgrace);
 130         info->dqi_igrace = le32_to_cpu(dinfo.dqi_igrace);
 131         info->dqi_flags = le32_to_cpu(dinfo.dqi_flags);
 132         qinfo->dqi_sb = sb;
 133         qinfo->dqi_type = type;
 134         qinfo->dqi_blocks = le32_to_cpu(dinfo.dqi_blocks);
 135         qinfo->dqi_free_blk = le32_to_cpu(dinfo.dqi_free_blk);
 136         qinfo->dqi_free_entry = le32_to_cpu(dinfo.dqi_free_entry);
 137         qinfo->dqi_blocksize_bits = V2_DQBLKSIZE_BITS;
 138         qinfo->dqi_usable_bs = 1 << V2_DQBLKSIZE_BITS;
 139         qinfo->dqi_qtree_depth = qtree_depth(qinfo);
 140         if (version == 0) {
 141                 qinfo->dqi_entry_size = sizeof(struct v2r0_disk_dqblk);
 142                 qinfo->dqi_ops = &v2r0_qtree_ops;
 143         } else {
 144                 qinfo->dqi_entry_size = sizeof(struct v2r1_disk_dqblk);
 145                 qinfo->dqi_ops = &v2r1_qtree_ops;
 146         }
 147         return 0;
 148 }
 149
 150 /* Write information header to quota file */
 151 static int v2_write_file_info(struct super_block *sb, int type)
 152 {
 153         struct v2_disk_dqinfo dinfo;
 154         struct mem_dqinfo *info = sb_dqinfo(sb, type);
 155         struct qtree_mem_dqinfo *qinfo = info->dqi_priv;
 156         ssize_t size;
 157
 158         spin_lock(&dq_data_lock);
 159         info->dqi_flags &= ~DQF_INFO_DIRTY;
 160         dinfo.dqi_bgrace = cpu_to_le32(info->dqi_bgrace);
 161         dinfo.dqi_igrace = cpu_to_le32(info->dqi_igrace);
 162         dinfo.dqi_flags = cpu_to_le32(info->dqi_flags & DQF_MASK);
 163         spin_unlock(&dq_data_lock);
 164         dinfo.dqi_blocks = cpu_to_le32(qinfo->dqi_blocks);
 165         dinfo.dqi_free_blk = cpu_to_le32(qinfo->dqi_free_blk);
 166         dinfo.dqi_free_entry = cpu_to_le32(qinfo->dqi_free_entry);
 167         size = sb->s_op->quota_write(sb, type, (char *)&dinfo,
 168                sizeof(struct v2_disk_dqinfo), V2_DQINFOOFF);
 169         if (size != sizeof(struct v2_disk_dqinfo)) {
 170                 q_warn(KERN_WARNING "Can't write info structure on device %s.\n",
 171                         sb->s_id);
 172                 return -1;
 173         }
 174         return 0;
 175 }
 176
 177 static void v2r0_disk2memdqb(struct dquot *dquot, void *dp)
 178 {
 179         struct v2r0_disk_dqblk *d = dp, empty;
 180         struct mem_dqblk *m = &dquot->dq_dqb;
 181
 182         m->dqb_ihardlimit = le32_to_cpu(d->dqb_ihardlimit);
 183         m->dqb_isoftlimit = le32_to_cpu(d->dqb_isoftlimit);
 184         m->dqb_curinodes = le32_to_cpu(d->dqb_curinodes);
 185         m->dqb_itime = le64_to_cpu(d->dqb_itime);
 186         m->dqb_bhardlimit = v2_qbtos(le32_to_cpu(d->dqb_bhardlimit));
 187         m->dqb_bsoftlimit = v2_qbtos(le32_to_cpu(d->dqb_bsoftlimit));
 188         m->dqb_curspace = le64_to_cpu(d->dqb_curspace);
 189         m->dqb_btime = le64_to_cpu(d->dqb_btime);
 190         /* We need to escape back all-zero structure */
 191         memset(&empty, 0, sizeof(struct v2r0_disk_dqblk));
 192         empty.dqb_itime = cpu_to_le64(1);
 193         if (!memcmp(&empty, dp, sizeof(struct v2r0_disk_dqblk)))
 194                 m->dqb_itime = 0;
 195 }
 196
 197 static void v2r0_mem2diskdqb(void *dp, struct dquot *dquot)
 198 {
 199         struct v2r0_disk_dqblk *d = dp;
 200         struct mem_dqblk *m = &dquot->dq_dqb;
 201         struct qtree_mem_dqinfo *info =
 202                         sb_dqinfo(dquot->dq_sb, dquot->dq_type)->dqi_priv;
 203
 204         d->dqb_ihardlimit = cpu_to_le32(m->dqb_ihardlimit);
 205         d->dqb_isoftlimit = cpu_to_le32(m->dqb_isoftlimit);
 206         d->dqb_curinodes = cpu_to_le32(m->dqb_curinodes);
 207         d->dqb_itime = cpu_to_le64(m->dqb_itime);
 208         d->dqb_bhardlimit = cpu_to_le32(v2_stoqb(m->dqb_bhardlimit));
 209         d->dqb_bsoftlimit = cpu_to_le32(v2_stoqb(m->dqb_bsoftlimit));
 210         d->dqb_curspace = cpu_to_le64(m->dqb_curspace);
 211         d->dqb_btime = cpu_to_le64(m->dqb_btime);
 212         d->dqb_id = cpu_to_le32(dquot->dq_id);
 213         if (qtree_entry_unused(info, dp))
 214                 d->dqb_itime = cpu_to_le64(1);
 215 }
 216
 217 static int v2r0_is_id(void *dp, struct dquot *dquot)
 218 {
 219         struct v2r0_disk_dqblk *d = dp;
 220         struct qtree_mem_dqinfo *info =
 221                         sb_dqinfo(dquot->dq_sb, dquot->dq_type)->dqi_priv;
 222
 223         if (qtree_entry_unused(info, dp))
 224                 return 0;
 225         return le32_to_cpu(d->dqb_id) == dquot->dq_id;
 226 }
 227
 228 static void v2r1_disk2memdqb(struct dquot *dquot, void *dp)
 229 {
 230         struct v2r1_disk_dqblk *d = dp, empty;
 231         struct mem_dqblk *m = &dquot->dq_dqb;
 232
 233         m->dqb_ihardlimit = le64_to_cpu(d->dqb_ihardlimit);
 234         m->dqb_isoftlimit = le64_to_cpu(d->dqb_isoftlimit);
 235         m->dqb_curinodes = le64_to_cpu(d->dqb_curinodes);
 236         m->dqb_itime = le64_to_cpu(d->dqb_itime);
 237         m->dqb_bhardlimit = v2_qbtos(le64_to_cpu(d->dqb_bhardlimit));
 238         m->dqb_bsoftlimit = v2_qbtos(le64_to_cpu(d->dqb_bsoftlimit));
 239         m->dqb_curspace = le64_to_cpu(d->dqb_curspace);
 240         m->dqb_btime = le64_to_cpu(d->dqb_btime);
 241         /* We need to escape back all-zero structure */
 242         memset(&empty, 0, sizeof(struct v2r1_disk_dqblk));
 243         empty.dqb_itime = cpu_to_le64(1);
 244         if (!memcmp(&empty, dp, sizeof(struct v2r1_disk_dqblk)))
 245                 m->dqb_itime = 0;
 246 }
 247
 248 static void v2r1_mem2diskdqb(void *dp, struct dquot *dquot)
 249 {
 250         struct v2r1_disk_dqblk *d = dp;
 251         struct mem_dqblk *m = &dquot->dq_dqb;
 252         struct qtree_mem_dqinfo *info =
 253                         sb_dqinfo(dquot->dq_sb, dquot->dq_type)->dqi_priv;
 254
 255         d->dqb_ihardlimit = cpu_to_le64(m->dqb_ihardlimit);
 256         d->dqb_isoftlimit = cpu_to_le64(m->dqb_isoftlimit);
 257         d->dqb_curinodes = cpu_to_le64(m->dqb_curinodes);
 258         d->dqb_itime = cpu_to_le64(m->dqb_itime);
 259         d->dqb_bhardlimit = cpu_to_le64(v2_stoqb(m->dqb_bhardlimit));
 260         d->dqb_bsoftlimit = cpu_to_le64(v2_stoqb(m->dqb_bsoftlimit));
 261         d->dqb_curspace = cpu_to_le64(m->dqb_curspace);
 262         d->dqb_btime = cpu_to_le64(m->dqb_btime);
 263         d->dqb_id = cpu_to_le32(dquot->dq_id);
 264         if (qtree_entry_unused(info, dp))
 265                 d->dqb_itime = cpu_to_le64(1);
 266 }
 267
 268 static int v2r1_is_id(void *dp, struct dquot *dquot)
 269 {
 270         struct v2r1_disk_dqblk *d = dp;
 271         struct qtree_mem_dqinfo *info =
 272                         sb_dqinfo(dquot->dq_sb, dquot->dq_type)->dqi_priv;
 273
 274         if (qtree_entry_unused(info, dp))
 275                 return 0;
 276         return le32_to_cpu(d->dqb_id) == dquot->dq_id;
 277 }
 278
 279 static int v2_read_dquot(struct dquot *dquot)
 280 {
 281         return qtree_read_dquot(sb_dqinfo(dquot->dq_sb, dquot->dq_type)->dqi_priv, dquot);
 282 }
 283
 284 static int v2_write_dquot(struct dquot *dquot)
 285 {
 286         return qtree_write_dquot(sb_dqinfo(dquot->dq_sb, dquot->dq_type)->dqi_priv, dquot);
 287 }
 288
 289 static int v2_release_dquot(struct dquot *dquot)
 290 {
 291         return qtree_release_dquot(sb_dqinfo(dquot->dq_sb, dquot->dq_type)->dqi_priv, dquot);
 292 }
 293
 294 static int v2_free_file_info(struct super_block *sb, int type)
 295 {
 296         kfree(sb_dqinfo(sb, type)->dqi_priv);
 297         return 0;
 298 }
 299
 300 static const struct quota_format_ops v2_format_ops = {
 301         .check_quota_file       = v2_check_quota_file,
 302         .read_file_info         = v2_read_file_info,
 303         .write_file_info        = v2_write_file_info,
 304         .free_file_info         = v2_free_file_info,
 305         .read_dqblk             = v2_read_dquot,
 306         .commit_dqblk           = v2_write_dquot,
 307         .release_dqblk          = v2_release_dquot,
 308 };
 309
 310 static struct quota_format_type v2r0_quota_format = {
 311         .qf_fmt_id      = QFMT_VFS_V0,
 312         .qf_ops         = &v2_format_ops,
 313         .qf_owner       = THIS_MODULE
 314 };
 315
 316 static struct quota_format_type v2r1_quota_format = {
 317         .qf_fmt_id      = QFMT_VFS_V1,
 318         .qf_ops         = &v2_format_ops,
 319         .qf_owner       = THIS_MODULE
 320 };
 321
 322 static int __init init_v2_quota_format(void)
 323 {
 324         int ret;
 325
 326         ret = register_quota_format(&v2r0_quota_format);
 327         if (ret)
 328                 return ret;
 329         return register_quota_format(&v2r1_quota_format);
 330 }
 331
 332 static void __exit exit_v2_quota_format(void)
 333 {
 334         unregister_quota_format(&v2r0_quota_format);
 335         unregister_quota_format(&v2r1_quota_format);
 336 }
 337
 338 module_init(init_v2_quota_format);
 339 module_exit(exit_v2_quota_format);