1884d179dSJan Kara /* 2884d179dSJan Kara * vfsv0 quota IO operations on file 3884d179dSJan Kara */ 4884d179dSJan Kara 5884d179dSJan Kara #include <linux/errno.h> 6884d179dSJan Kara #include <linux/fs.h> 7884d179dSJan Kara #include <linux/mount.h> 8884d179dSJan Kara #include <linux/dqblk_v2.h> 9884d179dSJan Kara #include <linux/kernel.h> 10884d179dSJan Kara #include <linux/init.h> 11884d179dSJan Kara #include <linux/module.h> 12884d179dSJan Kara #include <linux/slab.h> 13884d179dSJan Kara #include <linux/quotaops.h> 14884d179dSJan Kara 15884d179dSJan Kara #include <asm/byteorder.h> 16884d179dSJan Kara 17884d179dSJan Kara #include "quota_tree.h" 18884d179dSJan Kara 19884d179dSJan Kara MODULE_AUTHOR("Jan Kara"); 20884d179dSJan Kara MODULE_DESCRIPTION("Quota trie support"); 21884d179dSJan Kara MODULE_LICENSE("GPL"); 22884d179dSJan Kara 23884d179dSJan Kara #define __QUOTA_QT_PARANOIA 24884d179dSJan Kara 25884d179dSJan Kara static int get_index(struct qtree_mem_dqinfo *info, qid_t id, int depth) 26884d179dSJan Kara { 27884d179dSJan Kara unsigned int epb = info->dqi_usable_bs >> 2; 28884d179dSJan Kara 29884d179dSJan Kara depth = info->dqi_qtree_depth - depth - 1; 30884d179dSJan Kara while (depth--) 31884d179dSJan Kara id /= epb; 32884d179dSJan Kara return id % epb; 33884d179dSJan Kara } 34884d179dSJan Kara 35884d179dSJan Kara /* Number of entries in one blocks */ 367a2435d8SJan Kara static int qtree_dqstr_in_blk(struct qtree_mem_dqinfo *info) 37884d179dSJan Kara { 38884d179dSJan Kara return (info->dqi_usable_bs - sizeof(struct qt_disk_dqdbheader)) 39884d179dSJan Kara / info->dqi_entry_size; 40884d179dSJan Kara } 41884d179dSJan Kara 42d26ac1a8SJan Kara static char *getdqbuf(size_t size) 43884d179dSJan Kara { 44d26ac1a8SJan Kara char *buf = kmalloc(size, GFP_NOFS); 45884d179dSJan Kara if (!buf) 46268157baSJan Kara printk(KERN_WARNING 47268157baSJan Kara "VFS: Not enough memory for quota buffers.\n"); 48884d179dSJan Kara return buf; 49884d179dSJan Kara } 50884d179dSJan Kara 517a2435d8SJan Kara static ssize_t read_blk(struct qtree_mem_dqinfo *info, uint blk, char *buf) 52884d179dSJan Kara { 53884d179dSJan Kara struct super_block *sb = info->dqi_sb; 54884d179dSJan Kara 55884d179dSJan Kara memset(buf, 0, info->dqi_usable_bs); 56d26ac1a8SJan Kara return sb->s_op->quota_read(sb, info->dqi_type, buf, 57884d179dSJan Kara info->dqi_usable_bs, blk << info->dqi_blocksize_bits); 58884d179dSJan Kara } 59884d179dSJan Kara 607a2435d8SJan Kara static ssize_t write_blk(struct qtree_mem_dqinfo *info, uint blk, char *buf) 61884d179dSJan Kara { 62884d179dSJan Kara struct super_block *sb = info->dqi_sb; 631907131bSJiaying Zhang ssize_t ret; 64884d179dSJan Kara 651907131bSJiaying Zhang ret = sb->s_op->quota_write(sb, info->dqi_type, buf, 66884d179dSJan Kara info->dqi_usable_bs, blk << info->dqi_blocksize_bits); 671907131bSJiaying Zhang if (ret != info->dqi_usable_bs) { 68*fb5ffb0eSJiaying Zhang quota_error(sb, "dquota write failed"); 691907131bSJiaying Zhang if (ret >= 0) 701907131bSJiaying Zhang ret = -EIO; 711907131bSJiaying Zhang } 721907131bSJiaying Zhang return ret; 73884d179dSJan Kara } 74884d179dSJan Kara 75884d179dSJan Kara /* Remove empty block from list and return it */ 76884d179dSJan Kara static int get_free_dqblk(struct qtree_mem_dqinfo *info) 77884d179dSJan Kara { 78d26ac1a8SJan Kara char *buf = getdqbuf(info->dqi_usable_bs); 79884d179dSJan Kara struct qt_disk_dqdbheader *dh = (struct qt_disk_dqdbheader *)buf; 80884d179dSJan Kara int ret, blk; 81884d179dSJan Kara 82884d179dSJan Kara if (!buf) 83884d179dSJan Kara return -ENOMEM; 84884d179dSJan Kara if (info->dqi_free_blk) { 85884d179dSJan Kara blk = info->dqi_free_blk; 86884d179dSJan Kara ret = read_blk(info, blk, buf); 87884d179dSJan Kara if (ret < 0) 88884d179dSJan Kara goto out_buf; 89884d179dSJan Kara info->dqi_free_blk = le32_to_cpu(dh->dqdh_next_free); 90884d179dSJan Kara } 91884d179dSJan Kara else { 92884d179dSJan Kara memset(buf, 0, info->dqi_usable_bs); 93884d179dSJan Kara /* Assure block allocation... */ 94884d179dSJan Kara ret = write_blk(info, info->dqi_blocks, buf); 95884d179dSJan Kara if (ret < 0) 96884d179dSJan Kara goto out_buf; 97884d179dSJan Kara blk = info->dqi_blocks++; 98884d179dSJan Kara } 99884d179dSJan Kara mark_info_dirty(info->dqi_sb, info->dqi_type); 100884d179dSJan Kara ret = blk; 101884d179dSJan Kara out_buf: 102d26ac1a8SJan Kara kfree(buf); 103884d179dSJan Kara return ret; 104884d179dSJan Kara } 105884d179dSJan Kara 106884d179dSJan Kara /* Insert empty block to the list */ 107d26ac1a8SJan Kara static int put_free_dqblk(struct qtree_mem_dqinfo *info, char *buf, uint blk) 108884d179dSJan Kara { 109884d179dSJan Kara struct qt_disk_dqdbheader *dh = (struct qt_disk_dqdbheader *)buf; 110884d179dSJan Kara int err; 111884d179dSJan Kara 112884d179dSJan Kara dh->dqdh_next_free = cpu_to_le32(info->dqi_free_blk); 113884d179dSJan Kara dh->dqdh_prev_free = cpu_to_le32(0); 114884d179dSJan Kara dh->dqdh_entries = cpu_to_le16(0); 115884d179dSJan Kara err = write_blk(info, blk, buf); 116884d179dSJan Kara if (err < 0) 117884d179dSJan Kara return err; 118884d179dSJan Kara info->dqi_free_blk = blk; 119884d179dSJan Kara mark_info_dirty(info->dqi_sb, info->dqi_type); 120884d179dSJan Kara return 0; 121884d179dSJan Kara } 122884d179dSJan Kara 123884d179dSJan Kara /* Remove given block from the list of blocks with free entries */ 124268157baSJan Kara static int remove_free_dqentry(struct qtree_mem_dqinfo *info, char *buf, 125268157baSJan Kara uint blk) 126884d179dSJan Kara { 127d26ac1a8SJan Kara char *tmpbuf = getdqbuf(info->dqi_usable_bs); 128884d179dSJan Kara struct qt_disk_dqdbheader *dh = (struct qt_disk_dqdbheader *)buf; 129884d179dSJan Kara uint nextblk = le32_to_cpu(dh->dqdh_next_free); 130884d179dSJan Kara uint prevblk = le32_to_cpu(dh->dqdh_prev_free); 131884d179dSJan Kara int err; 132884d179dSJan Kara 133884d179dSJan Kara if (!tmpbuf) 134884d179dSJan Kara return -ENOMEM; 135884d179dSJan Kara if (nextblk) { 136884d179dSJan Kara err = read_blk(info, nextblk, tmpbuf); 137884d179dSJan Kara if (err < 0) 138884d179dSJan Kara goto out_buf; 139884d179dSJan Kara ((struct qt_disk_dqdbheader *)tmpbuf)->dqdh_prev_free = 140884d179dSJan Kara dh->dqdh_prev_free; 141884d179dSJan Kara err = write_blk(info, nextblk, tmpbuf); 142884d179dSJan Kara if (err < 0) 143884d179dSJan Kara goto out_buf; 144884d179dSJan Kara } 145884d179dSJan Kara if (prevblk) { 146884d179dSJan Kara err = read_blk(info, prevblk, tmpbuf); 147884d179dSJan Kara if (err < 0) 148884d179dSJan Kara goto out_buf; 149884d179dSJan Kara ((struct qt_disk_dqdbheader *)tmpbuf)->dqdh_next_free = 150884d179dSJan Kara dh->dqdh_next_free; 151884d179dSJan Kara err = write_blk(info, prevblk, tmpbuf); 152884d179dSJan Kara if (err < 0) 153884d179dSJan Kara goto out_buf; 154884d179dSJan Kara } else { 155884d179dSJan Kara info->dqi_free_entry = nextblk; 156884d179dSJan Kara mark_info_dirty(info->dqi_sb, info->dqi_type); 157884d179dSJan Kara } 158d26ac1a8SJan Kara kfree(tmpbuf); 159884d179dSJan Kara dh->dqdh_next_free = dh->dqdh_prev_free = cpu_to_le32(0); 160884d179dSJan Kara /* No matter whether write succeeds block is out of list */ 161884d179dSJan Kara if (write_blk(info, blk, buf) < 0) 162*fb5ffb0eSJiaying Zhang quota_error(info->dqi_sb, "Can't write block (%u) " 163*fb5ffb0eSJiaying Zhang "with free entries", blk); 164884d179dSJan Kara return 0; 165884d179dSJan Kara out_buf: 166d26ac1a8SJan Kara kfree(tmpbuf); 167884d179dSJan Kara return err; 168884d179dSJan Kara } 169884d179dSJan Kara 170884d179dSJan Kara /* Insert given block to the beginning of list with free entries */ 171268157baSJan Kara static int insert_free_dqentry(struct qtree_mem_dqinfo *info, char *buf, 172268157baSJan Kara uint blk) 173884d179dSJan Kara { 174d26ac1a8SJan Kara char *tmpbuf = getdqbuf(info->dqi_usable_bs); 175884d179dSJan Kara struct qt_disk_dqdbheader *dh = (struct qt_disk_dqdbheader *)buf; 176884d179dSJan Kara int err; 177884d179dSJan Kara 178884d179dSJan Kara if (!tmpbuf) 179884d179dSJan Kara return -ENOMEM; 180884d179dSJan Kara dh->dqdh_next_free = cpu_to_le32(info->dqi_free_entry); 181884d179dSJan Kara dh->dqdh_prev_free = cpu_to_le32(0); 182884d179dSJan Kara err = write_blk(info, blk, buf); 183884d179dSJan Kara if (err < 0) 184884d179dSJan Kara goto out_buf; 185884d179dSJan Kara if (info->dqi_free_entry) { 186884d179dSJan Kara err = read_blk(info, info->dqi_free_entry, tmpbuf); 187884d179dSJan Kara if (err < 0) 188884d179dSJan Kara goto out_buf; 189884d179dSJan Kara ((struct qt_disk_dqdbheader *)tmpbuf)->dqdh_prev_free = 190884d179dSJan Kara cpu_to_le32(blk); 191884d179dSJan Kara err = write_blk(info, info->dqi_free_entry, tmpbuf); 192884d179dSJan Kara if (err < 0) 193884d179dSJan Kara goto out_buf; 194884d179dSJan Kara } 195d26ac1a8SJan Kara kfree(tmpbuf); 196884d179dSJan Kara info->dqi_free_entry = blk; 197884d179dSJan Kara mark_info_dirty(info->dqi_sb, info->dqi_type); 198884d179dSJan Kara return 0; 199884d179dSJan Kara out_buf: 200d26ac1a8SJan Kara kfree(tmpbuf); 201884d179dSJan Kara return err; 202884d179dSJan Kara } 203884d179dSJan Kara 204884d179dSJan Kara /* Is the entry in the block free? */ 205884d179dSJan Kara int qtree_entry_unused(struct qtree_mem_dqinfo *info, char *disk) 206884d179dSJan Kara { 207884d179dSJan Kara int i; 208884d179dSJan Kara 209884d179dSJan Kara for (i = 0; i < info->dqi_entry_size; i++) 210884d179dSJan Kara if (disk[i]) 211884d179dSJan Kara return 0; 212884d179dSJan Kara return 1; 213884d179dSJan Kara } 214884d179dSJan Kara EXPORT_SYMBOL(qtree_entry_unused); 215884d179dSJan Kara 216884d179dSJan Kara /* Find space for dquot */ 217884d179dSJan Kara static uint find_free_dqentry(struct qtree_mem_dqinfo *info, 218884d179dSJan Kara struct dquot *dquot, int *err) 219884d179dSJan Kara { 220884d179dSJan Kara uint blk, i; 221884d179dSJan Kara struct qt_disk_dqdbheader *dh; 222d26ac1a8SJan Kara char *buf = getdqbuf(info->dqi_usable_bs); 223884d179dSJan Kara char *ddquot; 224884d179dSJan Kara 225884d179dSJan Kara *err = 0; 226884d179dSJan Kara if (!buf) { 227884d179dSJan Kara *err = -ENOMEM; 228884d179dSJan Kara return 0; 229884d179dSJan Kara } 230884d179dSJan Kara dh = (struct qt_disk_dqdbheader *)buf; 231884d179dSJan Kara if (info->dqi_free_entry) { 232884d179dSJan Kara blk = info->dqi_free_entry; 233884d179dSJan Kara *err = read_blk(info, blk, buf); 234884d179dSJan Kara if (*err < 0) 235884d179dSJan Kara goto out_buf; 236884d179dSJan Kara } else { 237884d179dSJan Kara blk = get_free_dqblk(info); 238884d179dSJan Kara if ((int)blk < 0) { 239884d179dSJan Kara *err = blk; 240d26ac1a8SJan Kara kfree(buf); 241884d179dSJan Kara return 0; 242884d179dSJan Kara } 243884d179dSJan Kara memset(buf, 0, info->dqi_usable_bs); 244268157baSJan Kara /* This is enough as the block is already zeroed and the entry 245268157baSJan Kara * list is empty... */ 246884d179dSJan Kara info->dqi_free_entry = blk; 247884d179dSJan Kara mark_info_dirty(dquot->dq_sb, dquot->dq_type); 248884d179dSJan Kara } 249884d179dSJan Kara /* Block will be full? */ 250884d179dSJan Kara if (le16_to_cpu(dh->dqdh_entries) + 1 >= qtree_dqstr_in_blk(info)) { 251884d179dSJan Kara *err = remove_free_dqentry(info, buf, blk); 252884d179dSJan Kara if (*err < 0) { 253*fb5ffb0eSJiaying Zhang quota_error(dquot->dq_sb, "Can't remove block (%u) " 254*fb5ffb0eSJiaying Zhang "from entry free list", blk); 255884d179dSJan Kara goto out_buf; 256884d179dSJan Kara } 257884d179dSJan Kara } 258884d179dSJan Kara le16_add_cpu(&dh->dqdh_entries, 1); 259884d179dSJan Kara /* Find free structure in block */ 260268157baSJan Kara ddquot = buf + sizeof(struct qt_disk_dqdbheader); 261268157baSJan Kara for (i = 0; i < qtree_dqstr_in_blk(info); i++) { 262268157baSJan Kara if (qtree_entry_unused(info, ddquot)) 263268157baSJan Kara break; 264268157baSJan Kara ddquot += info->dqi_entry_size; 265268157baSJan Kara } 266884d179dSJan Kara #ifdef __QUOTA_QT_PARANOIA 267884d179dSJan Kara if (i == qtree_dqstr_in_blk(info)) { 268*fb5ffb0eSJiaying Zhang quota_error(dquot->dq_sb, "Data block full but it shouldn't"); 269884d179dSJan Kara *err = -EIO; 270884d179dSJan Kara goto out_buf; 271884d179dSJan Kara } 272884d179dSJan Kara #endif 273884d179dSJan Kara *err = write_blk(info, blk, buf); 274884d179dSJan Kara if (*err < 0) { 275*fb5ffb0eSJiaying Zhang quota_error(dquot->dq_sb, "Can't write quota data block %u", 276*fb5ffb0eSJiaying Zhang blk); 277884d179dSJan Kara goto out_buf; 278884d179dSJan Kara } 279884d179dSJan Kara dquot->dq_off = (blk << info->dqi_blocksize_bits) + 280884d179dSJan Kara sizeof(struct qt_disk_dqdbheader) + 281884d179dSJan Kara i * info->dqi_entry_size; 282d26ac1a8SJan Kara kfree(buf); 283884d179dSJan Kara return blk; 284884d179dSJan Kara out_buf: 285d26ac1a8SJan Kara kfree(buf); 286884d179dSJan Kara return 0; 287884d179dSJan Kara } 288884d179dSJan Kara 289884d179dSJan Kara /* Insert reference to structure into the trie */ 290884d179dSJan Kara static int do_insert_tree(struct qtree_mem_dqinfo *info, struct dquot *dquot, 291884d179dSJan Kara uint *treeblk, int depth) 292884d179dSJan Kara { 293d26ac1a8SJan Kara char *buf = getdqbuf(info->dqi_usable_bs); 294884d179dSJan Kara int ret = 0, newson = 0, newact = 0; 295884d179dSJan Kara __le32 *ref; 296884d179dSJan Kara uint newblk; 297884d179dSJan Kara 298884d179dSJan Kara if (!buf) 299884d179dSJan Kara return -ENOMEM; 300884d179dSJan Kara if (!*treeblk) { 301884d179dSJan Kara ret = get_free_dqblk(info); 302884d179dSJan Kara if (ret < 0) 303884d179dSJan Kara goto out_buf; 304884d179dSJan Kara *treeblk = ret; 305884d179dSJan Kara memset(buf, 0, info->dqi_usable_bs); 306884d179dSJan Kara newact = 1; 307884d179dSJan Kara } else { 308884d179dSJan Kara ret = read_blk(info, *treeblk, buf); 309884d179dSJan Kara if (ret < 0) { 310*fb5ffb0eSJiaying Zhang quota_error(dquot->dq_sb, "Can't read tree quota " 311*fb5ffb0eSJiaying Zhang "block %u", *treeblk); 312884d179dSJan Kara goto out_buf; 313884d179dSJan Kara } 314884d179dSJan Kara } 315884d179dSJan Kara ref = (__le32 *)buf; 316884d179dSJan Kara newblk = le32_to_cpu(ref[get_index(info, dquot->dq_id, depth)]); 317884d179dSJan Kara if (!newblk) 318884d179dSJan Kara newson = 1; 319884d179dSJan Kara if (depth == info->dqi_qtree_depth - 1) { 320884d179dSJan Kara #ifdef __QUOTA_QT_PARANOIA 321884d179dSJan Kara if (newblk) { 322*fb5ffb0eSJiaying Zhang quota_error(dquot->dq_sb, "Inserting already present " 323*fb5ffb0eSJiaying Zhang "quota entry (block %u)", 324884d179dSJan Kara le32_to_cpu(ref[get_index(info, 325884d179dSJan Kara dquot->dq_id, depth)])); 326884d179dSJan Kara ret = -EIO; 327884d179dSJan Kara goto out_buf; 328884d179dSJan Kara } 329884d179dSJan Kara #endif 330884d179dSJan Kara newblk = find_free_dqentry(info, dquot, &ret); 331884d179dSJan Kara } else { 332884d179dSJan Kara ret = do_insert_tree(info, dquot, &newblk, depth+1); 333884d179dSJan Kara } 334884d179dSJan Kara if (newson && ret >= 0) { 335884d179dSJan Kara ref[get_index(info, dquot->dq_id, depth)] = 336884d179dSJan Kara cpu_to_le32(newblk); 337884d179dSJan Kara ret = write_blk(info, *treeblk, buf); 338884d179dSJan Kara } else if (newact && ret < 0) { 339884d179dSJan Kara put_free_dqblk(info, buf, *treeblk); 340884d179dSJan Kara } 341884d179dSJan Kara out_buf: 342d26ac1a8SJan Kara kfree(buf); 343884d179dSJan Kara return ret; 344884d179dSJan Kara } 345884d179dSJan Kara 346884d179dSJan Kara /* Wrapper for inserting quota structure into tree */ 347884d179dSJan Kara static inline int dq_insert_tree(struct qtree_mem_dqinfo *info, 348884d179dSJan Kara struct dquot *dquot) 349884d179dSJan Kara { 350884d179dSJan Kara int tmp = QT_TREEOFF; 351884d179dSJan Kara return do_insert_tree(info, dquot, &tmp, 0); 352884d179dSJan Kara } 353884d179dSJan Kara 354884d179dSJan Kara /* 355268157baSJan Kara * We don't have to be afraid of deadlocks as we never have quotas on quota 356268157baSJan Kara * files... 357884d179dSJan Kara */ 358884d179dSJan Kara int qtree_write_dquot(struct qtree_mem_dqinfo *info, struct dquot *dquot) 359884d179dSJan Kara { 360884d179dSJan Kara int type = dquot->dq_type; 361884d179dSJan Kara struct super_block *sb = dquot->dq_sb; 362884d179dSJan Kara ssize_t ret; 363d26ac1a8SJan Kara char *ddquot = getdqbuf(info->dqi_entry_size); 364884d179dSJan Kara 365884d179dSJan Kara if (!ddquot) 366884d179dSJan Kara return -ENOMEM; 367884d179dSJan Kara 368884d179dSJan Kara /* dq_off is guarded by dqio_mutex */ 369884d179dSJan Kara if (!dquot->dq_off) { 370884d179dSJan Kara ret = dq_insert_tree(info, dquot); 371884d179dSJan Kara if (ret < 0) { 372*fb5ffb0eSJiaying Zhang quota_error(sb, "Error %zd occurred while creating " 373*fb5ffb0eSJiaying Zhang "quota", ret); 374d26ac1a8SJan Kara kfree(ddquot); 375884d179dSJan Kara return ret; 376884d179dSJan Kara } 377884d179dSJan Kara } 378884d179dSJan Kara spin_lock(&dq_data_lock); 379884d179dSJan Kara info->dqi_ops->mem2disk_dqblk(ddquot, dquot); 380884d179dSJan Kara spin_unlock(&dq_data_lock); 381d26ac1a8SJan Kara ret = sb->s_op->quota_write(sb, type, ddquot, info->dqi_entry_size, 382d26ac1a8SJan Kara dquot->dq_off); 383884d179dSJan Kara if (ret != info->dqi_entry_size) { 384*fb5ffb0eSJiaying Zhang quota_error(sb, "dquota write failed"); 385884d179dSJan Kara if (ret >= 0) 386884d179dSJan Kara ret = -ENOSPC; 387884d179dSJan Kara } else { 388884d179dSJan Kara ret = 0; 389884d179dSJan Kara } 390dde95888SDmitry Monakhov dqstats_inc(DQST_WRITES); 391d26ac1a8SJan Kara kfree(ddquot); 392884d179dSJan Kara 393884d179dSJan Kara return ret; 394884d179dSJan Kara } 395884d179dSJan Kara EXPORT_SYMBOL(qtree_write_dquot); 396884d179dSJan Kara 397884d179dSJan Kara /* Free dquot entry in data block */ 398884d179dSJan Kara static int free_dqentry(struct qtree_mem_dqinfo *info, struct dquot *dquot, 399884d179dSJan Kara uint blk) 400884d179dSJan Kara { 401884d179dSJan Kara struct qt_disk_dqdbheader *dh; 402d26ac1a8SJan Kara char *buf = getdqbuf(info->dqi_usable_bs); 403884d179dSJan Kara int ret = 0; 404884d179dSJan Kara 405884d179dSJan Kara if (!buf) 406884d179dSJan Kara return -ENOMEM; 407884d179dSJan Kara if (dquot->dq_off >> info->dqi_blocksize_bits != blk) { 408*fb5ffb0eSJiaying Zhang quota_error(dquot->dq_sb, "Quota structure has offset to " 409*fb5ffb0eSJiaying Zhang "other block (%u) than it should (%u)", blk, 410884d179dSJan Kara (uint)(dquot->dq_off >> info->dqi_blocksize_bits)); 411884d179dSJan Kara goto out_buf; 412884d179dSJan Kara } 413884d179dSJan Kara ret = read_blk(info, blk, buf); 414884d179dSJan Kara if (ret < 0) { 415*fb5ffb0eSJiaying Zhang quota_error(dquot->dq_sb, "Can't read quota data block %u", 416*fb5ffb0eSJiaying Zhang blk); 417884d179dSJan Kara goto out_buf; 418884d179dSJan Kara } 419884d179dSJan Kara dh = (struct qt_disk_dqdbheader *)buf; 420884d179dSJan Kara le16_add_cpu(&dh->dqdh_entries, -1); 421884d179dSJan Kara if (!le16_to_cpu(dh->dqdh_entries)) { /* Block got free? */ 422884d179dSJan Kara ret = remove_free_dqentry(info, buf, blk); 423884d179dSJan Kara if (ret >= 0) 424884d179dSJan Kara ret = put_free_dqblk(info, buf, blk); 425884d179dSJan Kara if (ret < 0) { 426*fb5ffb0eSJiaying Zhang quota_error(dquot->dq_sb, "Can't move quota data block " 427*fb5ffb0eSJiaying Zhang "(%u) to free list", blk); 428884d179dSJan Kara goto out_buf; 429884d179dSJan Kara } 430884d179dSJan Kara } else { 431884d179dSJan Kara memset(buf + 432884d179dSJan Kara (dquot->dq_off & ((1 << info->dqi_blocksize_bits) - 1)), 433884d179dSJan Kara 0, info->dqi_entry_size); 434884d179dSJan Kara if (le16_to_cpu(dh->dqdh_entries) == 435884d179dSJan Kara qtree_dqstr_in_blk(info) - 1) { 436884d179dSJan Kara /* Insert will write block itself */ 437884d179dSJan Kara ret = insert_free_dqentry(info, buf, blk); 438884d179dSJan Kara if (ret < 0) { 439*fb5ffb0eSJiaying Zhang quota_error(dquot->dq_sb, "Can't insert quota " 440*fb5ffb0eSJiaying Zhang "data block (%u) to free entry list", blk); 441884d179dSJan Kara goto out_buf; 442884d179dSJan Kara } 443884d179dSJan Kara } else { 444884d179dSJan Kara ret = write_blk(info, blk, buf); 445884d179dSJan Kara if (ret < 0) { 446*fb5ffb0eSJiaying Zhang quota_error(dquot->dq_sb, "Can't write quota " 447*fb5ffb0eSJiaying Zhang "data block %u", blk); 448884d179dSJan Kara goto out_buf; 449884d179dSJan Kara } 450884d179dSJan Kara } 451884d179dSJan Kara } 452884d179dSJan Kara dquot->dq_off = 0; /* Quota is now unattached */ 453884d179dSJan Kara out_buf: 454d26ac1a8SJan Kara kfree(buf); 455884d179dSJan Kara return ret; 456884d179dSJan Kara } 457884d179dSJan Kara 458884d179dSJan Kara /* Remove reference to dquot from tree */ 459884d179dSJan Kara static int remove_tree(struct qtree_mem_dqinfo *info, struct dquot *dquot, 460884d179dSJan Kara uint *blk, int depth) 461884d179dSJan Kara { 462d26ac1a8SJan Kara char *buf = getdqbuf(info->dqi_usable_bs); 463884d179dSJan Kara int ret = 0; 464884d179dSJan Kara uint newblk; 465884d179dSJan Kara __le32 *ref = (__le32 *)buf; 466884d179dSJan Kara 467884d179dSJan Kara if (!buf) 468884d179dSJan Kara return -ENOMEM; 469884d179dSJan Kara ret = read_blk(info, *blk, buf); 470884d179dSJan Kara if (ret < 0) { 471*fb5ffb0eSJiaying Zhang quota_error(dquot->dq_sb, "Can't read quota data " 472*fb5ffb0eSJiaying Zhang "block %u", blk); 473884d179dSJan Kara goto out_buf; 474884d179dSJan Kara } 475884d179dSJan Kara newblk = le32_to_cpu(ref[get_index(info, dquot->dq_id, depth)]); 476884d179dSJan Kara if (depth == info->dqi_qtree_depth - 1) { 477884d179dSJan Kara ret = free_dqentry(info, dquot, newblk); 478884d179dSJan Kara newblk = 0; 479884d179dSJan Kara } else { 480884d179dSJan Kara ret = remove_tree(info, dquot, &newblk, depth+1); 481884d179dSJan Kara } 482884d179dSJan Kara if (ret >= 0 && !newblk) { 483884d179dSJan Kara int i; 484884d179dSJan Kara ref[get_index(info, dquot->dq_id, depth)] = cpu_to_le32(0); 485884d179dSJan Kara /* Block got empty? */ 486d26ac1a8SJan Kara for (i = 0; i < (info->dqi_usable_bs >> 2) && !ref[i]; i++) 487d26ac1a8SJan Kara ; 488884d179dSJan Kara /* Don't put the root block into the free block list */ 489884d179dSJan Kara if (i == (info->dqi_usable_bs >> 2) 490884d179dSJan Kara && *blk != QT_TREEOFF) { 491884d179dSJan Kara put_free_dqblk(info, buf, *blk); 492884d179dSJan Kara *blk = 0; 493884d179dSJan Kara } else { 494884d179dSJan Kara ret = write_blk(info, *blk, buf); 495884d179dSJan Kara if (ret < 0) 496*fb5ffb0eSJiaying Zhang quota_error(dquot->dq_sb, "Can't write quota " 497*fb5ffb0eSJiaying Zhang "tree block %u", blk); 498884d179dSJan Kara } 499884d179dSJan Kara } 500884d179dSJan Kara out_buf: 501d26ac1a8SJan Kara kfree(buf); 502884d179dSJan Kara return ret; 503884d179dSJan Kara } 504884d179dSJan Kara 505884d179dSJan Kara /* Delete dquot from tree */ 506884d179dSJan Kara int qtree_delete_dquot(struct qtree_mem_dqinfo *info, struct dquot *dquot) 507884d179dSJan Kara { 508884d179dSJan Kara uint tmp = QT_TREEOFF; 509884d179dSJan Kara 510884d179dSJan Kara if (!dquot->dq_off) /* Even not allocated? */ 511884d179dSJan Kara return 0; 512884d179dSJan Kara return remove_tree(info, dquot, &tmp, 0); 513884d179dSJan Kara } 514884d179dSJan Kara EXPORT_SYMBOL(qtree_delete_dquot); 515884d179dSJan Kara 516884d179dSJan Kara /* Find entry in block */ 517884d179dSJan Kara static loff_t find_block_dqentry(struct qtree_mem_dqinfo *info, 518884d179dSJan Kara struct dquot *dquot, uint blk) 519884d179dSJan Kara { 520d26ac1a8SJan Kara char *buf = getdqbuf(info->dqi_usable_bs); 521884d179dSJan Kara loff_t ret = 0; 522884d179dSJan Kara int i; 523884d179dSJan Kara char *ddquot; 524884d179dSJan Kara 525884d179dSJan Kara if (!buf) 526884d179dSJan Kara return -ENOMEM; 527884d179dSJan Kara ret = read_blk(info, blk, buf); 528884d179dSJan Kara if (ret < 0) { 529*fb5ffb0eSJiaying Zhang quota_error(dquot->dq_sb, "Can't read quota tree " 530*fb5ffb0eSJiaying Zhang "block %u", blk); 531884d179dSJan Kara goto out_buf; 532884d179dSJan Kara } 533268157baSJan Kara ddquot = buf + sizeof(struct qt_disk_dqdbheader); 534268157baSJan Kara for (i = 0; i < qtree_dqstr_in_blk(info); i++) { 535268157baSJan Kara if (info->dqi_ops->is_id(ddquot, dquot)) 536268157baSJan Kara break; 537268157baSJan Kara ddquot += info->dqi_entry_size; 538268157baSJan Kara } 539884d179dSJan Kara if (i == qtree_dqstr_in_blk(info)) { 540*fb5ffb0eSJiaying Zhang quota_error(dquot->dq_sb, "Quota for id %u referenced " 541*fb5ffb0eSJiaying Zhang "but not present", dquot->dq_id); 542884d179dSJan Kara ret = -EIO; 543884d179dSJan Kara goto out_buf; 544884d179dSJan Kara } else { 545884d179dSJan Kara ret = (blk << info->dqi_blocksize_bits) + sizeof(struct 546884d179dSJan Kara qt_disk_dqdbheader) + i * info->dqi_entry_size; 547884d179dSJan Kara } 548884d179dSJan Kara out_buf: 549d26ac1a8SJan Kara kfree(buf); 550884d179dSJan Kara return ret; 551884d179dSJan Kara } 552884d179dSJan Kara 553884d179dSJan Kara /* Find entry for given id in the tree */ 554884d179dSJan Kara static loff_t find_tree_dqentry(struct qtree_mem_dqinfo *info, 555884d179dSJan Kara struct dquot *dquot, uint blk, int depth) 556884d179dSJan Kara { 557d26ac1a8SJan Kara char *buf = getdqbuf(info->dqi_usable_bs); 558884d179dSJan Kara loff_t ret = 0; 559884d179dSJan Kara __le32 *ref = (__le32 *)buf; 560884d179dSJan Kara 561884d179dSJan Kara if (!buf) 562884d179dSJan Kara return -ENOMEM; 563884d179dSJan Kara ret = read_blk(info, blk, buf); 564884d179dSJan Kara if (ret < 0) { 565*fb5ffb0eSJiaying Zhang quota_error(dquot->dq_sb, "Can't read quota tree block %u", 566*fb5ffb0eSJiaying Zhang blk); 567884d179dSJan Kara goto out_buf; 568884d179dSJan Kara } 569884d179dSJan Kara ret = 0; 570884d179dSJan Kara blk = le32_to_cpu(ref[get_index(info, dquot->dq_id, depth)]); 571884d179dSJan Kara if (!blk) /* No reference? */ 572884d179dSJan Kara goto out_buf; 573884d179dSJan Kara if (depth < info->dqi_qtree_depth - 1) 574884d179dSJan Kara ret = find_tree_dqentry(info, dquot, blk, depth+1); 575884d179dSJan Kara else 576884d179dSJan Kara ret = find_block_dqentry(info, dquot, blk); 577884d179dSJan Kara out_buf: 578d26ac1a8SJan Kara kfree(buf); 579884d179dSJan Kara return ret; 580884d179dSJan Kara } 581884d179dSJan Kara 582884d179dSJan Kara /* Find entry for given id in the tree - wrapper function */ 583884d179dSJan Kara static inline loff_t find_dqentry(struct qtree_mem_dqinfo *info, 584884d179dSJan Kara struct dquot *dquot) 585884d179dSJan Kara { 586884d179dSJan Kara return find_tree_dqentry(info, dquot, QT_TREEOFF, 0); 587884d179dSJan Kara } 588884d179dSJan Kara 589884d179dSJan Kara int qtree_read_dquot(struct qtree_mem_dqinfo *info, struct dquot *dquot) 590884d179dSJan Kara { 591884d179dSJan Kara int type = dquot->dq_type; 592884d179dSJan Kara struct super_block *sb = dquot->dq_sb; 593884d179dSJan Kara loff_t offset; 594d26ac1a8SJan Kara char *ddquot; 595884d179dSJan Kara int ret = 0; 596884d179dSJan Kara 597884d179dSJan Kara #ifdef __QUOTA_QT_PARANOIA 598884d179dSJan Kara /* Invalidated quota? */ 599884d179dSJan Kara if (!sb_dqopt(dquot->dq_sb)->files[type]) { 600*fb5ffb0eSJiaying Zhang quota_error(sb, "Quota invalidated while reading!"); 601884d179dSJan Kara return -EIO; 602884d179dSJan Kara } 603884d179dSJan Kara #endif 604884d179dSJan Kara /* Do we know offset of the dquot entry in the quota file? */ 605884d179dSJan Kara if (!dquot->dq_off) { 606884d179dSJan Kara offset = find_dqentry(info, dquot); 607884d179dSJan Kara if (offset <= 0) { /* Entry not present? */ 608884d179dSJan Kara if (offset < 0) 609*fb5ffb0eSJiaying Zhang quota_error(sb, "Can't read quota structure " 610*fb5ffb0eSJiaying Zhang "for id %u", dquot->dq_id); 611884d179dSJan Kara dquot->dq_off = 0; 612884d179dSJan Kara set_bit(DQ_FAKE_B, &dquot->dq_flags); 613884d179dSJan Kara memset(&dquot->dq_dqb, 0, sizeof(struct mem_dqblk)); 614884d179dSJan Kara ret = offset; 615884d179dSJan Kara goto out; 616884d179dSJan Kara } 617884d179dSJan Kara dquot->dq_off = offset; 618884d179dSJan Kara } 619884d179dSJan Kara ddquot = getdqbuf(info->dqi_entry_size); 620884d179dSJan Kara if (!ddquot) 621884d179dSJan Kara return -ENOMEM; 622d26ac1a8SJan Kara ret = sb->s_op->quota_read(sb, type, ddquot, info->dqi_entry_size, 623d26ac1a8SJan Kara dquot->dq_off); 624884d179dSJan Kara if (ret != info->dqi_entry_size) { 625884d179dSJan Kara if (ret >= 0) 626884d179dSJan Kara ret = -EIO; 627*fb5ffb0eSJiaying Zhang quota_error(sb, "Error while reading quota structure for id %u", 628*fb5ffb0eSJiaying Zhang dquot->dq_id); 629884d179dSJan Kara set_bit(DQ_FAKE_B, &dquot->dq_flags); 630884d179dSJan Kara memset(&dquot->dq_dqb, 0, sizeof(struct mem_dqblk)); 631d26ac1a8SJan Kara kfree(ddquot); 632884d179dSJan Kara goto out; 633884d179dSJan Kara } 634884d179dSJan Kara spin_lock(&dq_data_lock); 635884d179dSJan Kara info->dqi_ops->disk2mem_dqblk(dquot, ddquot); 636884d179dSJan Kara if (!dquot->dq_dqb.dqb_bhardlimit && 637884d179dSJan Kara !dquot->dq_dqb.dqb_bsoftlimit && 638884d179dSJan Kara !dquot->dq_dqb.dqb_ihardlimit && 639884d179dSJan Kara !dquot->dq_dqb.dqb_isoftlimit) 640884d179dSJan Kara set_bit(DQ_FAKE_B, &dquot->dq_flags); 641884d179dSJan Kara spin_unlock(&dq_data_lock); 642d26ac1a8SJan Kara kfree(ddquot); 643884d179dSJan Kara out: 644dde95888SDmitry Monakhov dqstats_inc(DQST_READS); 645884d179dSJan Kara return ret; 646884d179dSJan Kara } 647884d179dSJan Kara EXPORT_SYMBOL(qtree_read_dquot); 648884d179dSJan Kara 649884d179dSJan Kara /* Check whether dquot should not be deleted. We know we are 650884d179dSJan Kara * the only one operating on dquot (thanks to dq_lock) */ 651884d179dSJan Kara int qtree_release_dquot(struct qtree_mem_dqinfo *info, struct dquot *dquot) 652884d179dSJan Kara { 653268157baSJan Kara if (test_bit(DQ_FAKE_B, &dquot->dq_flags) && 654268157baSJan Kara !(dquot->dq_dqb.dqb_curinodes | dquot->dq_dqb.dqb_curspace)) 655884d179dSJan Kara return qtree_delete_dquot(info, dquot); 656884d179dSJan Kara return 0; 657884d179dSJan Kara } 658884d179dSJan Kara EXPORT_SYMBOL(qtree_release_dquot); 659