release/src-rt-6.x.4708/linux/linux-2.6.36/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                 quota_error(sb, "Failed header read: expected=%zd got=%zd",
  67                             sizeof(struct v2_disk_dqheader), size);
  68                 return 0;
  69         }
  70         return 1;
  71 }
  72
  73 /* Check whether given file is really vfsv0 quotafile */
  74 static int v2_check_quota_file(struct super_block *sb, int type)
  75 {
  76         struct v2_disk_dqheader dqhead;
  77         static const uint quota_magics[] = V2_INITQMAGICS;
  78         static const uint quota_versions[] = V2_INITQVERSIONS;
  79
  80         if (!v2_read_header(sb, type, &dqhead))
  81                 return 0;
  82         if (le32_to_cpu(dqhead.dqh_magic) != quota_magics[type] ||
  83             le32_to_cpu(dqhead.dqh_version) > quota_versions[type])
  84                 return 0;
  85         return 1;
  86 }
  87
  88 /* Read information header from quota file */
  89 static int v2_read_file_info(struct super_block *sb, int type)
  90 {
  91         struct v2_disk_dqinfo dinfo;
  92         struct v2_disk_dqheader dqhead;
  93         struct mem_dqinfo *info = sb_dqinfo(sb, type);
  94         struct qtree_mem_dqinfo *qinfo;
  95         ssize_t size;
  96         unsigned int version;
  97
  98         if (!v2_read_header(sb, type, &dqhead))
  99                 return -1;
 100         version = le32_to_cpu(dqhead.dqh_version);
 101         if ((info->dqi_fmt_id == QFMT_VFS_V0 && version != 0) ||
 102             (info->dqi_fmt_id == QFMT_VFS_V1 && version != 1))
 103                 return -1;
 104
 105         size = sb->s_op->quota_read(sb, type, (char *)&dinfo,
 106                sizeof(struct v2_disk_dqinfo), V2_DQINFOOFF);
 107         if (size != sizeof(struct v2_disk_dqinfo)) {
 108                 quota_error(sb, "Can't read info structure");
 109                 return -1;
 110         }
 111         info->dqi_priv = kmalloc(sizeof(struct qtree_mem_dqinfo), GFP_NOFS);
 112         if (!info->dqi_priv) {
 113                 printk(KERN_WARNING
 114                        "Not enough memory for quota information structure.\n");
 115                 return -1;
 116         }
 117         qinfo = info->dqi_priv;
 118         if (version == 0) {
 119                 /* limits are stored as unsigned 32-bit data */
 120                 info->dqi_maxblimit = 0xffffffff;
 121                 info->dqi_maxilimit = 0xffffffff;
 122         } else {
 123                 /* used space is stored as unsigned 64-bit value */
 124                 info->dqi_maxblimit = 0xffffffffffffffffULL;    /* 2^64-1 */
 125                 info->dqi_maxilimit = 0xffffffffffffffffULL;
 126         }
 127         info->dqi_bgrace = le32_to_cpu(dinfo.dqi_bgrace);
 128         info->dqi_igrace = le32_to_cpu(dinfo.dqi_igrace);
 129         info->dqi_flags = le32_to_cpu(dinfo.dqi_flags);
 130         qinfo->dqi_sb = sb;
 131         qinfo->dqi_type = type;
 132         qinfo->dqi_blocks = le32_to_cpu(dinfo.dqi_blocks);
 133         qinfo->dqi_free_blk = le32_to_cpu(dinfo.dqi_free_blk);
 134         qinfo->dqi_free_entry = le32_to_cpu(dinfo.dqi_free_entry);
 135         qinfo->dqi_blocksize_bits = V2_DQBLKSIZE_BITS;
 136         qinfo->dqi_usable_bs = 1 << V2_DQBLKSIZE_BITS;
 137         qinfo->dqi_qtree_depth = qtree_depth(qinfo);
 138         if (version == 0) {
 139                 qinfo->dqi_entry_size = sizeof(struct v2r0_disk_dqblk);
 140                 qinfo->dqi_ops = &v2r0_qtree_ops;
 141         } else {
 142                 qinfo->dqi_entry_size = sizeof(struct v2r1_disk_dqblk);
 143                 qinfo->dqi_ops = &v2r1_qtree_ops;
 144         }
 145         return 0;
 146 }
 147
 148 /* Write information header to quota file */
 149 static int v2_write_file_info(struct super_block *sb, int type)
 150 {
 151         struct v2_disk_dqinfo dinfo;
 152         struct mem_dqinfo *info = sb_dqinfo(sb, type);
 153         struct qtree_mem_dqinfo *qinfo = info->dqi_priv;
 154         ssize_t size;
 155
 156         spin_lock(&dq_data_lock);
 157         info->dqi_flags &= ~DQF_INFO_DIRTY;
 158         dinfo.dqi_bgrace = cpu_to_le32(info->dqi_bgrace);
 159         dinfo.dqi_igrace = cpu_to_le32(info->dqi_igrace);
 160         dinfo.dqi_flags = cpu_to_le32(info->dqi_flags & DQF_MASK);
 161         spin_unlock(&dq_data_lock);
 162         dinfo.dqi_blocks = cpu_to_le32(qinfo->dqi_blocks);
 163         dinfo.dqi_free_blk = cpu_to_le32(qinfo->dqi_free_blk);
 164         dinfo.dqi_free_entry = cpu_to_le32(qinfo->dqi_free_entry);
 165         size = sb->s_op->quota_write(sb, type, (char *)&dinfo,
 166                sizeof(struct v2_disk_dqinfo), V2_DQINFOOFF);
 167         if (size != sizeof(struct v2_disk_dqinfo)) {
 168                 quota_error(sb, "Can't write info structure");
 169                 return -1;
 170         }
 171         return 0;
 172 }
 173
 174 static void v2r0_disk2memdqb(struct dquot *dquot, void *dp)
 175 {
 176         struct v2r0_disk_dqblk *d = dp, empty;
 177         struct mem_dqblk *m = &dquot->dq_dqb;
 178
 179         m->dqb_ihardlimit = le32_to_cpu(d->dqb_ihardlimit);
 180         m->dqb_isoftlimit = le32_to_cpu(d->dqb_isoftlimit);
 181         m->dqb_curinodes = le32_to_cpu(d->dqb_curinodes);
 182         m->dqb_itime = le64_to_cpu(d->dqb_itime);
 183         m->dqb_bhardlimit = v2_qbtos(le32_to_cpu(d->dqb_bhardlimit));
 184         m->dqb_bsoftlimit = v2_qbtos(le32_to_cpu(d->dqb_bsoftlimit));
 185         m->dqb_curspace = le64_to_cpu(d->dqb_curspace);
 186         m->dqb_btime = le64_to_cpu(d->dqb_btime);
 187         /* We need to escape back all-zero structure */
 188         memset(&empty, 0, sizeof(struct v2r0_disk_dqblk));
 189         empty.dqb_itime = cpu_to_le64(1);
 190         if (!memcmp(&empty, dp, sizeof(struct v2r0_disk_dqblk)))
 191                 m->dqb_itime = 0;
 192 }
 193
 194 static void v2r0_mem2diskdqb(void *dp, struct dquot *dquot)
 195 {
 196         struct v2r0_disk_dqblk *d = dp;
 197         struct mem_dqblk *m = &dquot->dq_dqb;
 198         struct qtree_mem_dqinfo *info =
 199                         sb_dqinfo(dquot->dq_sb, dquot->dq_type)->dqi_priv;
 200
 201         d->dqb_ihardlimit = cpu_to_le32(m->dqb_ihardlimit);
 202         d->dqb_isoftlimit = cpu_to_le32(m->dqb_isoftlimit);
 203         d->dqb_curinodes = cpu_to_le32(m->dqb_curinodes);
 204         d->dqb_itime = cpu_to_le64(m->dqb_itime);
 205         d->dqb_bhardlimit = cpu_to_le32(v2_stoqb(m->dqb_bhardlimit));
 206         d->dqb_bsoftlimit = cpu_to_le32(v2_stoqb(m->dqb_bsoftlimit));
 207         d->dqb_curspace = cpu_to_le64(m->dqb_curspace);
 208         d->dqb_btime = cpu_to_le64(m->dqb_btime);
 209         d->dqb_id = cpu_to_le32(dquot->dq_id);
 210         if (qtree_entry_unused(info, dp))
 211                 d->dqb_itime = cpu_to_le64(1);
 212 }
 213
 214 static int v2r0_is_id(void *dp, struct dquot *dquot)
 215 {
 216         struct v2r0_disk_dqblk *d = dp;
 217         struct qtree_mem_dqinfo *info =
 218                         sb_dqinfo(dquot->dq_sb, dquot->dq_type)->dqi_priv;
 219
 220         if (qtree_entry_unused(info, dp))
 221                 return 0;
 222         return le32_to_cpu(d->dqb_id) == dquot->dq_id;
 223 }
 224
 225 static void v2r1_disk2memdqb(struct dquot *dquot, void *dp)
 226 {
 227         struct v2r1_disk_dqblk *d = dp, empty;
 228         struct mem_dqblk *m = &dquot->dq_dqb;
 229
 230         m->dqb_ihardlimit = le64_to_cpu(d->dqb_ihardlimit);
 231         m->dqb_isoftlimit = le64_to_cpu(d->dqb_isoftlimit);
 232         m->dqb_curinodes = le64_to_cpu(d->dqb_curinodes);
 233         m->dqb_itime = le64_to_cpu(d->dqb_itime);
 234         m->dqb_bhardlimit = v2_qbtos(le64_to_cpu(d->dqb_bhardlimit));
 235         m->dqb_bsoftlimit = v2_qbtos(le64_to_cpu(d->dqb_bsoftlimit));
 236         m->dqb_curspace = le64_to_cpu(d->dqb_curspace);
 237         m->dqb_btime = le64_to_cpu(d->dqb_btime);
 238         /* We need to escape back all-zero structure */
 239         memset(&empty, 0, sizeof(struct v2r1_disk_dqblk));
 240         empty.dqb_itime = cpu_to_le64(1);
 241         if (!memcmp(&empty, dp, sizeof(struct v2r1_disk_dqblk)))
 242                 m->dqb_itime = 0;
 243 }
 244
 245 static void v2r1_mem2diskdqb(void *dp, struct dquot *dquot)
 246 {
 247         struct v2r1_disk_dqblk *d = dp;
 248         struct mem_dqblk *m = &dquot->dq_dqb;
 249         struct qtree_mem_dqinfo *info =
 250                         sb_dqinfo(dquot->dq_sb, dquot->dq_type)->dqi_priv;
 251
 252         d->dqb_ihardlimit = cpu_to_le64(m->dqb_ihardlimit);
 253         d->dqb_isoftlimit = cpu_to_le64(m->dqb_isoftlimit);
 254         d->dqb_curinodes = cpu_to_le64(m->dqb_curinodes);
 255         d->dqb_itime = cpu_to_le64(m->dqb_itime);
 256         d->dqb_bhardlimit = cpu_to_le64(v2_stoqb(m->dqb_bhardlimit));
 257         d->dqb_bsoftlimit = cpu_to_le64(v2_stoqb(m->dqb_bsoftlimit));
 258         d->dqb_curspace = cpu_to_le64(m->dqb_curspace);
 259         d->dqb_btime = cpu_to_le64(m->dqb_btime);
 260         d->dqb_id = cpu_to_le32(dquot->dq_id);
 261         if (qtree_entry_unused(info, dp))
 262                 d->dqb_itime = cpu_to_le64(1);
 263 }
 264
 265 static int v2r1_is_id(void *dp, struct dquot *dquot)
 266 {
 267         struct v2r1_disk_dqblk *d = dp;
 268         struct qtree_mem_dqinfo *info =
 269                         sb_dqinfo(dquot->dq_sb, dquot->dq_type)->dqi_priv;
 270
 271         if (qtree_entry_unused(info, dp))
 272                 return 0;
 273         return le32_to_cpu(d->dqb_id) == dquot->dq_id;
 274 }
 275
 276 static int v2_read_dquot(struct dquot *dquot)
 277 {
 278         return qtree_read_dquot(sb_dqinfo(dquot->dq_sb, dquot->dq_type)->dqi_priv, dquot);
 279 }
 280
 281 static int v2_write_dquot(struct dquot *dquot)
 282 {
 283         return qtree_write_dquot(sb_dqinfo(dquot->dq_sb, dquot->dq_type)->dqi_priv, dquot);
 284 }
 285
 286 static int v2_release_dquot(struct dquot *dquot)
 287 {
 288         return qtree_release_dquot(sb_dqinfo(dquot->dq_sb, dquot->dq_type)->dqi_priv, dquot);
 289 }
 290
 291 static int v2_free_file_info(struct super_block *sb, int type)
 292 {
 293         kfree(sb_dqinfo(sb, type)->dqi_priv);
 294         return 0;
 295 }
 296
 297 static const struct quota_format_ops v2_format_ops = {
 298         .check_quota_file       = v2_check_quota_file,
 299         .read_file_info         = v2_read_file_info,
 300         .write_file_info        = v2_write_file_info,
 301         .free_file_info         = v2_free_file_info,
 302         .read_dqblk             = v2_read_dquot,
 303         .commit_dqblk           = v2_write_dquot,
 304         .release_dqblk          = v2_release_dquot,
 305 };
 306
 307 static struct quota_format_type v2r0_quota_format = {
 308         .qf_fmt_id      = QFMT_VFS_V0,
 309         .qf_ops         = &v2_format_ops,
 310         .qf_owner       = THIS_MODULE
 311 };
 312
 313 static struct quota_format_type v2r1_quota_format = {
 314         .qf_fmt_id      = QFMT_VFS_V1,
 315         .qf_ops         = &v2_format_ops,
 316         .qf_owner       = THIS_MODULE
 317 };
 318
 319 static int __init init_v2_quota_format(void)
 320 {
 321         int ret;
 322
 323         ret = register_quota_format(&v2r0_quota_format);
 324         if (ret)
 325                 return ret;
 326         return register_quota_format(&v2r1_quota_format);
 327 }
 328
 329 static void __exit exit_v2_quota_format(void)
 330 {
 331         unregister_quota_format(&v2r0_quota_format);
 332         unregister_quota_format(&v2r1_quota_format);
 333 }
 334
 335 module_init(init_v2_quota_format);
 336 module_exit(exit_v2_quota_format);