lib/support/quotaio.c

   1 /** quotaio.c
   2  *
   3  * Generic IO operations on quotafiles
   4  * Jan Kara <jack@suse.cz> - sponsored by SuSE CR
   5  * Aditya Kali <adityakali@google.com> - Ported to e2fsprogs
   6  */
   7
   8 #include "config.h"
   9 #include <stdio.h>
  10 #include <errno.h>
  11 #include <string.h>
  12 #include <unistd.h>
  13 #include <stdlib.h>
  14 #include <time.h>
  15 #include <sys/types.h>
  16 #include <sys/stat.h>
  17 #include <sys/file.h>
  18 #include <assert.h>
  19
  20 #include "common.h"
  21 #include "quotaio.h"
  22
  23 static const char * const extensions[MAXQUOTAS] = {
  24         [USRQUOTA] = "user",
  25         [GRPQUOTA] = "group",
  26         [PRJQUOTA] = "project",
  27 };
  28 static const char * const basenames[] = {
  29         "",             /* undefined */
  30         "quota",        /* QFMT_VFS_OLD */
  31         "aquota",       /* QFMT_VFS_V0 */
  32         "",             /* QFMT_OCFS2 */
  33         "aquota"        /* QFMT_VFS_V1 */
  34 };
  35
  36 /* Header in all newer quotafiles */
  37 struct disk_dqheader {
  38         __le32 dqh_magic;
  39         __le32 dqh_version;
  40 } __attribute__ ((packed));
  41
  42 /**
  43  * Convert type of quota to written representation
  44  */
  45 const char *quota_type2name(enum quota_type qtype)
  46 {
  47         if (qtype >= MAXQUOTAS)
  48                 return "unknown";
  49         return extensions[qtype];
  50 }
  51
  52 ext2_ino_t quota_type2inum(enum quota_type qtype,
  53                            struct ext2_super_block *sb)
  54 {
  55         switch (qtype) {
  56         case USRQUOTA:
  57                 return EXT4_USR_QUOTA_INO;
  58         case GRPQUOTA:
  59                 return EXT4_GRP_QUOTA_INO;
  60         case PRJQUOTA:
  61                 return sb->s_prj_quota_inum;
  62         default:
  63                 return 0;
  64         }
  65         return 0;
  66 }
  67
  68 /**
  69  * Creates a quota file name for given type and format.
  70  */
  71 const char *quota_get_qf_name(enum quota_type type, int fmt, char *buf)
  72 {
  73         if (!buf)
  74                 return NULL;
  75         snprintf(buf, QUOTA_NAME_LEN, "%s.%s",
  76                  basenames[fmt], extensions[type]);
  77
  78         return buf;
  79 }
  80
  81 /*
  82  * Set grace time if needed
  83  */
  84 void update_grace_times(struct dquot *q)
  85 {
  86         time_t now;
  87
  88         time(&now);
  89         if (q->dq_dqb.dqb_bsoftlimit && toqb(q->dq_dqb.dqb_curspace) >
  90                         q->dq_dqb.dqb_bsoftlimit) {
  91                 if (!q->dq_dqb.dqb_btime)
  92                         q->dq_dqb.dqb_btime =
  93                                 now + q->dq_h->qh_info.dqi_bgrace;
  94         } else {
  95                 q->dq_dqb.dqb_btime = 0;
  96         }
  97
  98         if (q->dq_dqb.dqb_isoftlimit && q->dq_dqb.dqb_curinodes >
  99                         q->dq_dqb.dqb_isoftlimit) {
 100                 if (!q->dq_dqb.dqb_itime)
 101                                 q->dq_dqb.dqb_itime =
 102                                         now + q->dq_h->qh_info.dqi_igrace;
 103         } else {
 104                 q->dq_dqb.dqb_itime = 0;
 105         }
 106 }
 107
 108 errcode_t quota_inode_truncate(ext2_filsys fs, ext2_ino_t ino)
 109 {
 110         struct ext2_inode inode;
 111         errcode_t err;
 112         enum quota_type qtype;
 113
 114         if ((err = ext2fs_read_inode(fs, ino, &inode)))
 115                 return err;
 116
 117         for (qtype = 0; qtype < MAXQUOTAS; qtype++)
 118                 if (ino == quota_type2inum(qtype, fs->super))
 119                         break;
 120
 121         if (qtype != MAXQUOTAS) {
 122                 ext2fs_set_dtime(fs, &inode);
 123                 if (!ext2fs_inode_has_valid_blocks2(fs, &inode))
 124                         return 0;
 125                 err = ext2fs_punch(fs, ino, &inode, NULL, 0, ~0ULL);
 126                 if (err)
 127                         return err;
 128                 fs->flags &= ~EXT2_FLAG_SUPER_ONLY;
 129                 memset(&inode, 0, sizeof(struct ext2_inode));
 130         } else {
 131                 inode.i_flags &= ~EXT2_IMMUTABLE_FL;
 132         }
 133         err = ext2fs_write_inode(fs, ino, &inode);
 134         return err;
 135 }
 136
 137 /* Functions to read/write quota file. */
 138 static unsigned int quota_write_nomount(struct quota_file *qf,
 139                                         ext2_loff_t offset,
 140                                         void *buf, unsigned int size)
 141 {
 142         ext2_file_t     e2_file = qf->e2_file;
 143         unsigned int    bytes_written = 0;
 144         errcode_t       err;
 145
 146         err = ext2fs_file_llseek(e2_file, offset, EXT2_SEEK_SET, NULL);
 147         if (err) {
 148                 log_err("ext2fs_file_llseek failed: %ld", err);
 149                 return 0;
 150         }
 151
 152         err = ext2fs_file_write(e2_file, buf, size, &bytes_written);
 153         if (err) {
 154                 log_err("ext2fs_file_write failed: %ld", err);
 155                 return 0;
 156         }
 157
 158         /* Correct inode.i_size is set in end_io. */
 159         return bytes_written;
 160 }
 161
 162 static unsigned int quota_read_nomount(struct quota_file *qf,
 163                                        ext2_loff_t offset,
 164                                        void *buf, unsigned int size)
 165 {
 166         ext2_file_t     e2_file = qf->e2_file;
 167         unsigned int    bytes_read = 0;
 168         errcode_t       err;
 169
 170         err = ext2fs_file_llseek(e2_file, offset, EXT2_SEEK_SET, NULL);
 171         if (err) {
 172                 log_err("ext2fs_file_llseek failed: %ld", err);
 173                 return 0;
 174         }
 175
 176         err = ext2fs_file_read(e2_file, buf, size, &bytes_read);
 177         if (err) {
 178                 log_err("ext2fs_file_read failed: %ld", err);
 179                 return 0;
 180         }
 181
 182         return bytes_read;
 183 }
 184
 185 /*
 186  * Detect quota format and initialize quota IO
 187  */
 188 errcode_t quota_file_open(quota_ctx_t qctx, struct quota_handle *h,
 189                           ext2_ino_t qf_ino, enum quota_type qtype,
 190                           int fmt, int flags)
 191 {
 192         ext2_filsys fs = qctx->fs;
 193         ext2_file_t e2_file;
 194         errcode_t err;
 195         int allocated_handle = 0;
 196
 197         if (qtype >= MAXQUOTAS)
 198                 return EINVAL;
 199
 200         if (fmt == -1)
 201                 fmt = QFMT_VFS_V1;
 202
 203         err = ext2fs_read_bitmaps(fs);
 204         if (err)
 205                 return err;
 206
 207         if (qf_ino == 0)
 208                 qf_ino = *quota_sb_inump(fs->super, qtype);
 209
 210         log_debug("Opening quota ino=%u, type=%d", qf_ino, qtype);
 211         err = ext2fs_file_open(fs, qf_ino, flags, &e2_file);
 212         if (err) {
 213                 log_err("ext2fs_file_open failed: %s", error_message(err));
 214                 return err;
 215         }
 216
 217         if (!h) {
 218                 if (qctx->quota_file[qtype]) {
 219                         h = qctx->quota_file[qtype];
 220                         if (((flags & EXT2_FILE_WRITE) == 0) ||
 221                             (h->qh_file_flags & EXT2_FILE_WRITE)) {
 222                                 ext2fs_file_close(e2_file);
 223                                 return 0;
 224                         }
 225                         (void) quota_file_close(qctx, h);
 226                 }
 227                 err = ext2fs_get_mem(sizeof(struct quota_handle), &h);
 228                 if (err) {
 229                         log_err("Unable to allocate quota handle");
 230                         ext2fs_file_close(e2_file);
 231                         return err;
 232                 }
 233                 allocated_handle = 1;
 234         }
 235
 236         h->qh_qf.e2_file = e2_file;
 237         h->qh_qf.fs = fs;
 238         h->qh_qf.ino = qf_ino;
 239         h->e2fs_write = quota_write_nomount;
 240         h->e2fs_read = quota_read_nomount;
 241         h->qh_file_flags = flags;
 242         h->qh_io_flags = 0;
 243         h->qh_type = qtype;
 244         h->qh_fmt = fmt;
 245         memset(&h->qh_info, 0, sizeof(h->qh_info));
 246         h->qh_ops = &quotafile_ops_2;
 247
 248         if (h->qh_ops->check_file &&
 249             (h->qh_ops->check_file(h, qtype, fmt) == 0)) {
 250                 log_err("qh_ops->check_file failed");
 251                 err = EIO;
 252                 goto errout;
 253         }
 254
 255         if (h->qh_ops->init_io && (h->qh_ops->init_io(h) < 0)) {
 256                 log_err("qh_ops->init_io failed");
 257                 err = EIO;
 258                 goto errout;
 259         }
 260         if (allocated_handle)
 261                 qctx->quota_file[qtype] = h;
 262
 263         return 0;
 264 errout:
 265         ext2fs_file_close(e2_file);
 266         if (allocated_handle)
 267                 ext2fs_free_mem(&h);
 268         return err;
 269 }
 270
 271 static errcode_t quota_inode_init_new(ext2_filsys fs, ext2_ino_t ino)
 272 {
 273         struct ext2_inode inode;
 274         errcode_t err = 0;
 275         time_t now;
 276
 277         err = ext2fs_read_inode(fs, ino, &inode);
 278         if (err) {
 279                 log_err("ex2fs_read_inode failed");
 280                 return err;
 281         }
 282
 283         if (EXT2_I_SIZE(&inode)) {
 284                 err = quota_inode_truncate(fs, ino);
 285                 if (err)
 286                         return err;
 287         }
 288
 289         memset(&inode, 0, sizeof(struct ext2_inode));
 290         ext2fs_iblk_set(fs, &inode, 0);
 291         now = fs->now ? fs->now : time(0);
 292         ext2fs_inode_xtime_set(&inode, i_atime, now);
 293         ext2fs_inode_xtime_set(&inode, i_ctime, now);
 294         ext2fs_inode_xtime_set(&inode, i_mtime, now);
 295         inode.i_links_count = 1;
 296         inode.i_mode = LINUX_S_IFREG | 0600;
 297         inode.i_flags |= EXT2_IMMUTABLE_FL;
 298         if (ext2fs_has_feature_extents(fs->super))
 299                 inode.i_flags |= EXT4_EXTENTS_FL;
 300
 301         err = ext2fs_write_new_inode(fs, ino, &inode);
 302         if (err) {
 303                 log_err("ext2fs_write_new_inode failed: %ld", err);
 304                 return err;
 305         }
 306         return err;
 307 }
 308
 309 /*
 310  * Create new quotafile of specified format on given filesystem
 311  */
 312 errcode_t quota_file_create(struct quota_handle *h, ext2_filsys fs,
 313                             enum quota_type qtype, int fmt)
 314 {
 315         ext2_file_t e2_file;
 316         errcode_t err;
 317         ext2_ino_t qf_inum = 0;
 318
 319         if (fmt == -1)
 320                 fmt = QFMT_VFS_V1;
 321
 322         h->qh_qf.fs = fs;
 323         qf_inum = quota_type2inum(qtype, fs->super);
 324         if (qf_inum == 0 && qtype == PRJQUOTA) {
 325                 err = ext2fs_new_inode(fs, EXT2_ROOT_INO, LINUX_S_IFREG | 0600,
 326                                        0, &qf_inum);
 327                 if (err)
 328                         return err;
 329                 ext2fs_inode_alloc_stats2(fs, qf_inum, +1, 0);
 330                 ext2fs_mark_ib_dirty(fs);
 331         } else if (qf_inum == 0) {
 332                 return EXT2_ET_BAD_INODE_NUM;
 333         }
 334
 335         err = ext2fs_read_bitmaps(fs);
 336         if (err)
 337                 goto out_err;
 338
 339         err = quota_inode_init_new(fs, qf_inum);
 340         if (err) {
 341                 log_err("init_new_quota_inode failed");
 342                 goto out_err;
 343         }
 344         h->qh_qf.ino = qf_inum;
 345         h->qh_file_flags = EXT2_FILE_WRITE | EXT2_FILE_CREATE;
 346         h->e2fs_write = quota_write_nomount;
 347         h->e2fs_read = quota_read_nomount;
 348
 349         log_debug("Creating quota ino=%u, type=%d", qf_inum, qtype);
 350         err = ext2fs_file_open(fs, qf_inum, h->qh_file_flags, &e2_file);
 351         if (err) {
 352                 log_err("ext2fs_file_open failed: %ld", err);
 353                 goto out_err;
 354         }
 355         h->qh_qf.e2_file = e2_file;
 356
 357         h->qh_io_flags = 0;
 358         h->qh_type = qtype;
 359         h->qh_fmt = fmt;
 360         memset(&h->qh_info, 0, sizeof(h->qh_info));
 361         h->qh_ops = &quotafile_ops_2;
 362
 363         if (h->qh_ops->new_io && (h->qh_ops->new_io(h) < 0)) {
 364                 log_err("qh_ops->new_io failed");
 365                 err = EIO;
 366                 goto out_err1;
 367         }
 368
 369         return 0;
 370
 371 out_err1:
 372         ext2fs_file_close(e2_file);
 373 out_err:
 374
 375         if (qf_inum)
 376                 quota_inode_truncate(fs, qf_inum);
 377
 378         return err;
 379 }
 380
 381 /*
 382  * Close quotafile and release handle
 383  */
 384 errcode_t quota_file_close(quota_ctx_t qctx, struct quota_handle *h)
 385 {
 386         if (h->qh_io_flags & IOFL_INFODIRTY) {
 387                 if (h->qh_ops->write_info && h->qh_ops->write_info(h) < 0)
 388                         return EIO;
 389                 h->qh_io_flags &= ~IOFL_INFODIRTY;
 390         }
 391
 392         if (h->qh_ops->end_io && h->qh_ops->end_io(h) < 0)
 393                 return EIO;
 394         if (h->qh_qf.e2_file)
 395                 ext2fs_file_close(h->qh_qf.e2_file);
 396         if (qctx->quota_file[h->qh_type] == h)
 397                 ext2fs_free_mem(&qctx->quota_file[h->qh_type]);
 398         return 0;
 399 }
 400
 401 /*
 402  * Create empty quota structure
 403  */
 404 struct dquot *get_empty_dquot(void)
 405 {
 406         struct dquot *dquot;
 407
 408         if (ext2fs_get_memzero(sizeof(struct dquot), &dquot)) {
 409                 log_err("Failed to allocate dquot");
 410                 return NULL;
 411         }
 412
 413         dquot->dq_id = -1;
 414         return dquot;
 415 }