fs/aufs/cpup.c

   1 /*
   2  * Copyright (C) 2005-2016 Junjiro R. Okajima
   3  *
   4  * This program, aufs is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License as published by
   6  * the Free Software Foundation; either version 2 of the License, or
   7  * (at your option) any later version.
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  16  */
  17
  18 /*
  19  * copy-up functions, see wbr_policy.c for copy-down
  20  */
  21
  22 #include <linux/fs_stack.h>
  23 #include <linux/mm.h>
  24 #include <linux/task_work.h>
  25 #include "aufs.h"
  26
  27 void au_cpup_attr_flags(struct inode *dst, unsigned int iflags)
  28 {
  29         const unsigned int mask = S_DEAD | S_SWAPFILE | S_PRIVATE
  30                 | S_NOATIME | S_NOCMTIME | S_AUTOMOUNT;
  31
  32         BUILD_BUG_ON(sizeof(iflags) != sizeof(dst->i_flags));
  33
  34         dst->i_flags |= iflags & ~mask;
  35         if (au_test_fs_notime(dst->i_sb))
  36                 dst->i_flags |= S_NOATIME | S_NOCMTIME;
  37 }
  38
  39 void au_cpup_attr_timesizes(struct inode *inode)
  40 {
  41         struct inode *h_inode;
  42
  43         h_inode = au_h_iptr(inode, au_ibtop(inode));
  44         fsstack_copy_attr_times(inode, h_inode);
  45         fsstack_copy_inode_size(inode, h_inode);
  46 }
  47
  48 void au_cpup_attr_nlink(struct inode *inode, int force)
  49 {
  50         struct inode *h_inode;
  51         struct super_block *sb;
  52         aufs_bindex_t bindex, bbot;
  53
  54         sb = inode->i_sb;
  55         bindex = au_ibtop(inode);
  56         h_inode = au_h_iptr(inode, bindex);
  57         if (!force
  58             && !S_ISDIR(h_inode->i_mode)
  59             && au_opt_test(au_mntflags(sb), PLINK)
  60             && au_plink_test(inode))
  61                 return;
  62
  63         /*
  64          * 0 can happen in revalidating.
  65          * h_inode->i_mutex may not be held here, but it is harmless since once
  66          * i_nlink reaches 0, it will never become positive except O_TMPFILE
  67          * case.
  68          * todo: O_TMPFILE+linkat(AT_SYMLINK_FOLLOW) bypassing aufs may cause
  69          *       the incorrect link count.
  70          */
  71         set_nlink(inode, h_inode->i_nlink);
  72
  73         /*
  74          * fewer nlink makes find(1) noisy, but larger nlink doesn't.
  75          * it may includes whplink directory.
  76          */
  77         if (S_ISDIR(h_inode->i_mode)) {
  78                 bbot = au_ibbot(inode);
  79                 for (bindex++; bindex <= bbot; bindex++) {
  80                         h_inode = au_h_iptr(inode, bindex);
  81                         if (h_inode)
  82                                 au_add_nlink(inode, h_inode);
  83                 }
  84         }
  85 }
  86
  87 void au_cpup_attr_changeable(struct inode *inode)
  88 {
  89         struct inode *h_inode;
  90
  91         h_inode = au_h_iptr(inode, au_ibtop(inode));
  92         inode->i_mode = h_inode->i_mode;
  93         inode->i_uid = h_inode->i_uid;
  94         inode->i_gid = h_inode->i_gid;
  95         au_cpup_attr_timesizes(inode);
  96         au_cpup_attr_flags(inode, h_inode->i_flags);
  97 }
  98
  99 void au_cpup_igen(struct inode *inode, struct inode *h_inode)
 100 {
 101         struct au_iinfo *iinfo = au_ii(inode);
 102
 103         IiMustWriteLock(inode);
 104
 105         iinfo->ii_higen = h_inode->i_generation;
 106         iinfo->ii_hsb1 = h_inode->i_sb;
 107 }
 108
 109 void au_cpup_attr_all(struct inode *inode, int force)
 110 {
 111         struct inode *h_inode;
 112
 113         h_inode = au_h_iptr(inode, au_ibtop(inode));
 114         au_cpup_attr_changeable(inode);
 115         if (inode->i_nlink > 0)
 116                 au_cpup_attr_nlink(inode, force);
 117         inode->i_rdev = h_inode->i_rdev;
 118         inode->i_blkbits = h_inode->i_blkbits;
 119         au_cpup_igen(inode, h_inode);
 120 }
 121
 122 /* ---------------------------------------------------------------------- */
 123
 124 /* Note: dt_dentry and dt_h_dentry are not dget/dput-ed */
 125
 126 /* keep the timestamps of the parent dir when cpup */
 127 void au_dtime_store(struct au_dtime *dt, struct dentry *dentry,
 128                     struct path *h_path)
 129 {
 130         struct inode *h_inode;
 131
 132         dt->dt_dentry = dentry;
 133         dt->dt_h_path = *h_path;
 134         h_inode = d_inode(h_path->dentry);
 135         dt->dt_atime = h_inode->i_atime;
 136         dt->dt_mtime = h_inode->i_mtime;
 137         /* smp_mb(); */
 138 }
 139
 140 void au_dtime_revert(struct au_dtime *dt)
 141 {
 142         struct iattr attr;
 143         int err;
 144
 145         attr.ia_atime = dt->dt_atime;
 146         attr.ia_mtime = dt->dt_mtime;
 147         attr.ia_valid = ATTR_FORCE | ATTR_MTIME | ATTR_MTIME_SET
 148                 | ATTR_ATIME | ATTR_ATIME_SET;
 149
 150         /* no delegation since this is a directory */
 151         err = vfsub_notify_change(&dt->dt_h_path, &attr, /*delegated*/NULL);
 152         if (unlikely(err))
 153                 pr_warn("restoring timestamps failed(%d). ignored\n", err);
 154 }
 155
 156 /* ---------------------------------------------------------------------- */
 157
 158 /* internal use only */
 159 struct au_cpup_reg_attr {
 160         int             valid;
 161         struct kstat    st;
 162         unsigned int    iflags; /* inode->i_flags */
 163 };
 164
 165 static noinline_for_stack
 166 int cpup_iattr(struct dentry *dst, aufs_bindex_t bindex, struct dentry *h_src,
 167                struct au_cpup_reg_attr *h_src_attr)
 168 {
 169         int err, sbits, icex;
 170         unsigned int mnt_flags;
 171         unsigned char verbose;
 172         struct iattr ia;
 173         struct path h_path;
 174         struct inode *h_isrc, *h_idst;
 175         struct kstat *h_st;
 176         struct au_branch *br;
 177
 178         h_path.dentry = au_h_dptr(dst, bindex);
 179         h_idst = d_inode(h_path.dentry);
 180         br = au_sbr(dst->d_sb, bindex);
 181         h_path.mnt = au_br_mnt(br);
 182         h_isrc = d_inode(h_src);
 183         ia.ia_valid = ATTR_FORCE | ATTR_UID | ATTR_GID
 184                 | ATTR_ATIME | ATTR_MTIME
 185                 | ATTR_ATIME_SET | ATTR_MTIME_SET;
 186         if (h_src_attr && h_src_attr->valid) {
 187                 h_st = &h_src_attr->st;
 188                 ia.ia_uid = h_st->uid;
 189                 ia.ia_gid = h_st->gid;
 190                 ia.ia_atime = h_st->atime;
 191                 ia.ia_mtime = h_st->mtime;
 192                 if (h_idst->i_mode != h_st->mode
 193                     && !S_ISLNK(h_idst->i_mode)) {
 194                         ia.ia_valid |= ATTR_MODE;
 195                         ia.ia_mode = h_st->mode;
 196                 }
 197                 sbits = !!(h_st->mode & (S_ISUID | S_ISGID));
 198                 au_cpup_attr_flags(h_idst, h_src_attr->iflags);
 199         } else {
 200                 ia.ia_uid = h_isrc->i_uid;
 201                 ia.ia_gid = h_isrc->i_gid;
 202                 ia.ia_atime = h_isrc->i_atime;
 203                 ia.ia_mtime = h_isrc->i_mtime;
 204                 if (h_idst->i_mode != h_isrc->i_mode
 205                     && !S_ISLNK(h_idst->i_mode)) {
 206                         ia.ia_valid |= ATTR_MODE;
 207                         ia.ia_mode = h_isrc->i_mode;
 208                 }
 209                 sbits = !!(h_isrc->i_mode & (S_ISUID | S_ISGID));
 210                 au_cpup_attr_flags(h_idst, h_isrc->i_flags);
 211         }
 212         /* no delegation since it is just created */
 213         err = vfsub_notify_change(&h_path, &ia, /*delegated*/NULL);
 214
 215         /* is this nfs only? */
 216         if (!err && sbits && au_test_nfs(h_path.dentry->d_sb)) {
 217                 ia.ia_valid = ATTR_FORCE | ATTR_MODE;
 218                 ia.ia_mode = h_isrc->i_mode;
 219                 err = vfsub_notify_change(&h_path, &ia, /*delegated*/NULL);
 220         }
 221
 222         icex = br->br_perm & AuBrAttr_ICEX;
 223         if (!err) {
 224                 mnt_flags = au_mntflags(dst->d_sb);
 225                 verbose = !!au_opt_test(mnt_flags, VERBOSE);
 226                 err = au_cpup_xattr(h_path.dentry, h_src, icex, verbose);
 227         }
 228
 229         return err;
 230 }
 231
 232 /* ---------------------------------------------------------------------- */
 233
 234 static int au_do_copy_file(struct file *dst, struct file *src, loff_t len,
 235                            char *buf, unsigned long blksize)
 236 {
 237         int err;
 238         size_t sz, rbytes, wbytes;
 239         unsigned char all_zero;
 240         char *p, *zp;
 241         struct inode *h_inode;
 242         /* reduce stack usage */
 243         struct iattr *ia;
 244
 245         zp = page_address(ZERO_PAGE(0));
 246         if (unlikely(!zp))
 247                 return -ENOMEM; /* possible? */
 248
 249         err = 0;
 250         all_zero = 0;
 251         while (len) {
 252                 AuDbg("len %lld\n", len);
 253                 sz = blksize;
 254                 if (len < blksize)
 255                         sz = len;
 256
 257                 rbytes = 0;
 258                 /* todo: signal_pending? */
 259                 while (!rbytes || err == -EAGAIN || err == -EINTR) {
 260                         rbytes = vfsub_read_k(src, buf, sz, &src->f_pos);
 261                         err = rbytes;
 262                 }
 263                 if (unlikely(err < 0))
 264                         break;
 265
 266                 all_zero = 0;
 267                 if (len >= rbytes && rbytes == blksize)
 268                         all_zero = !memcmp(buf, zp, rbytes);
 269                 if (!all_zero) {
 270                         wbytes = rbytes;
 271                         p = buf;
 272                         while (wbytes) {
 273                                 size_t b;
 274
 275                                 b = vfsub_write_k(dst, p, wbytes, &dst->f_pos);
 276                                 err = b;
 277                                 /* todo: signal_pending? */
 278                                 if (unlikely(err == -EAGAIN || err == -EINTR))
 279                                         continue;
 280                                 if (unlikely(err < 0))
 281                                         break;
 282                                 wbytes -= b;
 283                                 p += b;
 284                         }
 285                         if (unlikely(err < 0))
 286                                 break;
 287                 } else {
 288                         loff_t res;
 289
 290                         AuLabel(hole);
 291                         res = vfsub_llseek(dst, rbytes, SEEK_CUR);
 292                         err = res;
 293                         if (unlikely(res < 0))
 294                                 break;
 295                 }
 296                 len -= rbytes;
 297                 err = 0;
 298         }
 299
 300         /* the last block may be a hole */
 301         if (!err && all_zero) {
 302                 AuLabel(last hole);
 303
 304                 err = 1;
 305                 if (au_test_nfs(dst->f_path.dentry->d_sb)) {
 306                         /* nfs requires this step to make last hole */
 307                         /* is this only nfs? */
 308                         do {
 309                                 /* todo: signal_pending? */
 310                                 err = vfsub_write_k(dst, "\0", 1, &dst->f_pos);
 311                         } while (err == -EAGAIN || err == -EINTR);
 312                         if (err == 1)
 313                                 dst->f_pos--;
 314                 }
 315
 316                 if (err == 1) {
 317                         ia = (void *)buf;
 318                         ia->ia_size = dst->f_pos;
 319                         ia->ia_valid = ATTR_SIZE | ATTR_FILE;
 320                         ia->ia_file = dst;
 321                         h_inode = file_inode(dst);
 322                         inode_lock_nested(h_inode, AuLsc_I_CHILD2);
 323                         /* no delegation since it is just created */
 324                         err = vfsub_notify_change(&dst->f_path, ia,
 325                                                   /*delegated*/NULL);
 326                         inode_unlock(h_inode);
 327                 }
 328         }
 329
 330         return err;
 331 }
 332
 333 int au_copy_file(struct file *dst, struct file *src, loff_t len)
 334 {
 335         int err;
 336         unsigned long blksize;
 337         unsigned char do_kfree;
 338         char *buf;
 339
 340         err = -ENOMEM;
 341         blksize = dst->f_path.dentry->d_sb->s_blocksize;
 342         if (!blksize || PAGE_SIZE < blksize)
 343                 blksize = PAGE_SIZE;
 344         AuDbg("blksize %lu\n", blksize);
 345         do_kfree = (blksize != PAGE_SIZE && blksize >= sizeof(struct iattr *));
 346         if (do_kfree)
 347                 buf = kmalloc(blksize, GFP_NOFS);
 348         else
 349                 buf = (void *)__get_free_page(GFP_NOFS);
 350         if (unlikely(!buf))
 351                 goto out;
 352
 353         if (len > (1 << 22))
 354                 AuDbg("copying a large file %lld\n", (long long)len);
 355
 356         src->f_pos = 0;
 357         dst->f_pos = 0;
 358         err = au_do_copy_file(dst, src, len, buf, blksize);
 359         if (do_kfree)
 360                 au_delayed_kfree(buf);
 361         else
 362                 au_delayed_free_page((unsigned long)buf);
 363
 364 out:
 365         return err;
 366 }
 367
 368 /*
 369  * to support a sparse file which is opened with O_APPEND,
 370  * we need to close the file.
 371  */
 372 static int au_cp_regular(struct au_cp_generic *cpg)
 373 {
 374         int err, i;
 375         enum { SRC, DST };
 376         struct {
 377                 aufs_bindex_t bindex;
 378                 unsigned int flags;
 379                 struct dentry *dentry;
 380                 int force_wr;
 381                 struct file *file;
 382                 void *label;
 383         } *f, file[] = {
 384                 {
 385                         .bindex = cpg->bsrc,
 386                         .flags = O_RDONLY | O_NOATIME | O_LARGEFILE,
 387                         .label = &&out
 388                 },
 389                 {
 390                         .bindex = cpg->bdst,
 391                         .flags = O_WRONLY | O_NOATIME | O_LARGEFILE,
 392                         .force_wr = !!au_ftest_cpup(cpg->flags, RWDST),
 393                         .label = &&out_src
 394                 }
 395         };
 396         struct super_block *sb;
 397         struct inode *h_src_inode;
 398         struct task_struct *tsk = current;
 399
 400         /* bsrc branch can be ro/rw. */
 401         sb = cpg->dentry->d_sb;
 402         f = file;
 403         for (i = 0; i < 2; i++, f++) {
 404                 f->dentry = au_h_dptr(cpg->dentry, f->bindex);
 405                 f->file = au_h_open(cpg->dentry, f->bindex, f->flags,
 406                                     /*file*/NULL, f->force_wr);
 407                 err = PTR_ERR(f->file);
 408                 if (IS_ERR(f->file))
 409                         goto *f->label;
 410         }
 411
 412         /* try stopping to update while we copyup */
 413         h_src_inode = d_inode(file[SRC].dentry);
 414         if (!au_test_nfs(h_src_inode->i_sb))
 415                 IMustLock(h_src_inode);
 416         err = au_copy_file(file[DST].file, file[SRC].file, cpg->len);
 417
 418         /* i wonder if we had O_NO_DELAY_FPUT flag */
 419         if (tsk->flags & PF_KTHREAD)
 420                 __fput_sync(file[DST].file);
 421         else {
 422                 WARN(1, "%pD\nPlease report this warning to aufs-users ML",
 423                      file[DST].file);
 424                 fput(file[DST].file);
 425                 /*
 426                  * too bad.
 427                  * we have to call both since we don't know which place the file
 428                  * was added to.
 429                  */
 430                 task_work_run();
 431                 flush_delayed_fput();
 432         }
 433         au_sbr_put(sb, file[DST].bindex);
 434
 435 out_src:
 436         fput(file[SRC].file);
 437         au_sbr_put(sb, file[SRC].bindex);
 438 out:
 439         return err;
 440 }
 441
 442 static int au_do_cpup_regular(struct au_cp_generic *cpg,
 443                               struct au_cpup_reg_attr *h_src_attr)
 444 {
 445         int err, rerr;
 446         loff_t l;
 447         struct path h_path;
 448         struct inode *h_src_inode, *h_dst_inode;
 449
 450         err = 0;
 451         h_src_inode = au_h_iptr(d_inode(cpg->dentry), cpg->bsrc);
 452         l = i_size_read(h_src_inode);
 453         if (cpg->len == -1 || l < cpg->len)
 454                 cpg->len = l;
 455         if (cpg->len) {
 456                 /* try stopping to update while we are referencing */
 457                 inode_lock_nested(h_src_inode, AuLsc_I_CHILD);
 458                 au_pin_hdir_unlock(cpg->pin);
 459
 460                 h_path.dentry = au_h_dptr(cpg->dentry, cpg->bsrc);
 461                 h_path.mnt = au_sbr_mnt(cpg->dentry->d_sb, cpg->bsrc);
 462                 h_src_attr->iflags = h_src_inode->i_flags;
 463                 if (!au_test_nfs(h_src_inode->i_sb))
 464                         err = vfs_getattr(&h_path, &h_src_attr->st);
 465                 else {
 466                         inode_unlock(h_src_inode);
 467                         err = vfs_getattr(&h_path, &h_src_attr->st);
 468                         inode_lock_nested(h_src_inode, AuLsc_I_CHILD);
 469                 }
 470                 if (unlikely(err)) {
 471                         inode_unlock(h_src_inode);
 472                         goto out;
 473                 }
 474                 h_src_attr->valid = 1;
 475                 if (!au_test_nfs(h_src_inode->i_sb)) {
 476                         err = au_cp_regular(cpg);
 477                         inode_unlock(h_src_inode);
 478                 } else {
 479                         inode_unlock(h_src_inode);
 480                         err = au_cp_regular(cpg);
 481                 }
 482                 rerr = au_pin_hdir_relock(cpg->pin);
 483                 if (!err && rerr)
 484                         err = rerr;
 485         }
 486         if (!err && (h_src_inode->i_state & I_LINKABLE)) {
 487                 h_path.dentry = au_h_dptr(cpg->dentry, cpg->bdst);
 488                 h_dst_inode = d_inode(h_path.dentry);
 489                 spin_lock(&h_dst_inode->i_lock);
 490                 h_dst_inode->i_state |= I_LINKABLE;
 491                 spin_unlock(&h_dst_inode->i_lock);
 492         }
 493
 494 out:
 495         return err;
 496 }
 497
 498 static int au_do_cpup_symlink(struct path *h_path, struct dentry *h_src,
 499                               struct inode *h_dir)
 500 {
 501         int err, symlen;
 502         mm_segment_t old_fs;
 503         union {
 504                 char *k;
 505                 char __user *u;
 506         } sym;
 507         struct inode *h_inode = d_inode(h_src);
 508         const struct inode_operations *h_iop = h_inode->i_op;
 509
 510         err = -ENOSYS;
 511         if (unlikely(!h_iop->readlink))
 512                 goto out;
 513
 514         err = -ENOMEM;
 515         sym.k = (void *)__get_free_page(GFP_NOFS);
 516         if (unlikely(!sym.k))
 517                 goto out;
 518
 519         /* unnecessary to support mmap_sem since symlink is not mmap-able */
 520         old_fs = get_fs();
 521         set_fs(KERNEL_DS);
 522         symlen = h_iop->readlink(h_src, sym.u, PATH_MAX);
 523         err = symlen;
 524         set_fs(old_fs);
 525
 526         if (symlen > 0) {
 527                 sym.k[symlen] = 0;
 528                 err = vfsub_symlink(h_dir, h_path, sym.k);
 529         }
 530         au_delayed_free_page((unsigned long)sym.k);
 531
 532 out:
 533         return err;
 534 }
 535
 536 /*
 537  * regardless 'acl' option, reset all ACL.
 538  * All ACL will be copied up later from the original entry on the lower branch.
 539  */
 540 static int au_reset_acl(struct inode *h_dir, struct path *h_path, umode_t mode)
 541 {
 542         int err;
 543         struct dentry *h_dentry;
 544         struct inode *h_inode;
 545
 546         h_dentry = h_path->dentry;
 547         h_inode = d_inode(h_dentry);
 548         /* forget_all_cached_acls(h_inode)); */
 549         err = vfsub_removexattr(h_dentry, XATTR_NAME_POSIX_ACL_ACCESS);
 550         AuTraceErr(err);
 551         if (err == -EOPNOTSUPP)
 552                 err = 0;
 553         if (!err)
 554                 err = vfsub_acl_chmod(h_inode, mode);
 555
 556         AuTraceErr(err);
 557         return err;
 558 }
 559
 560 static int au_do_cpup_dir(struct au_cp_generic *cpg, struct dentry *dst_parent,
 561                           struct inode *h_dir, struct path *h_path)
 562 {
 563         int err;
 564         struct inode *dir, *inode;
 565
 566         err = vfsub_removexattr(h_path->dentry, XATTR_NAME_POSIX_ACL_DEFAULT);
 567         AuTraceErr(err);
 568         if (err == -EOPNOTSUPP)
 569                 err = 0;
 570         if (unlikely(err))
 571                 goto out;
 572
 573         /*
 574          * strange behaviour from the users view,
 575          * particularry setattr case
 576          */
 577         dir = d_inode(dst_parent);
 578         if (au_ibtop(dir) == cpg->bdst)
 579                 au_cpup_attr_nlink(dir, /*force*/1);
 580         inode = d_inode(cpg->dentry);
 581         au_cpup_attr_nlink(inode, /*force*/1);
 582
 583 out:
 584         return err;
 585 }
 586
 587 static noinline_for_stack
 588 int cpup_entry(struct au_cp_generic *cpg, struct dentry *dst_parent,
 589                struct au_cpup_reg_attr *h_src_attr)
 590 {
 591         int err;
 592         umode_t mode;
 593         unsigned int mnt_flags;
 594         unsigned char isdir, isreg, force;
 595         const unsigned char do_dt = !!au_ftest_cpup(cpg->flags, DTIME);
 596         struct au_dtime dt;
 597         struct path h_path;
 598         struct dentry *h_src, *h_dst, *h_parent;
 599         struct inode *h_inode, *h_dir;
 600         struct super_block *sb;
 601
 602         /* bsrc branch can be ro/rw. */
 603         h_src = au_h_dptr(cpg->dentry, cpg->bsrc);
 604         h_inode = d_inode(h_src);
 605         AuDebugOn(h_inode != au_h_iptr(d_inode(cpg->dentry), cpg->bsrc));
 606
 607         /* try stopping to be referenced while we are creating */
 608         h_dst = au_h_dptr(cpg->dentry, cpg->bdst);
 609         if (au_ftest_cpup(cpg->flags, RENAME))
 610                 AuDebugOn(strncmp(h_dst->d_name.name, AUFS_WH_PFX,
 611                                   AUFS_WH_PFX_LEN));
 612         h_parent = h_dst->d_parent; /* dir inode is locked */
 613         h_dir = d_inode(h_parent);
 614         IMustLock(h_dir);
 615         AuDebugOn(h_parent != h_dst->d_parent);
 616
 617         sb = cpg->dentry->d_sb;
 618         h_path.mnt = au_sbr_mnt(sb, cpg->bdst);
 619         if (do_dt) {
 620                 h_path.dentry = h_parent;
 621                 au_dtime_store(&dt, dst_parent, &h_path);
 622         }
 623         h_path.dentry = h_dst;
 624
 625         isreg = 0;
 626         isdir = 0;
 627         mode = h_inode->i_mode;
 628         switch (mode & S_IFMT) {
 629         case S_IFREG:
 630                 isreg = 1;
 631                 err = vfsub_create(h_dir, &h_path, S_IRUSR | S_IWUSR,
 632                                    /*want_excl*/true);
 633                 if (!err)
 634                         err = au_do_cpup_regular(cpg, h_src_attr);
 635                 break;
 636         case S_IFDIR:
 637                 isdir = 1;
 638                 err = vfsub_mkdir(h_dir, &h_path, mode);
 639                 if (!err)
 640                         err = au_do_cpup_dir(cpg, dst_parent, h_dir, &h_path);
 641                 break;
 642         case S_IFLNK:
 643                 err = au_do_cpup_symlink(&h_path, h_src, h_dir);
 644                 break;
 645         case S_IFCHR:
 646         case S_IFBLK:
 647                 AuDebugOn(!capable(CAP_MKNOD));
 648                 /*FALLTHROUGH*/
 649         case S_IFIFO:
 650         case S_IFSOCK:
 651                 err = vfsub_mknod(h_dir, &h_path, mode, h_inode->i_rdev);
 652                 break;
 653         default:
 654                 AuIOErr("Unknown inode type 0%o\n", mode);
 655                 err = -EIO;
 656         }
 657         if (!err)
 658                 err = au_reset_acl(h_dir, &h_path, mode);
 659
 660         mnt_flags = au_mntflags(sb);
 661         if (!au_opt_test(mnt_flags, UDBA_NONE)
 662             && !isdir
 663             && au_opt_test(mnt_flags, XINO)
 664             && (h_inode->i_nlink == 1
 665                 || (h_inode->i_state & I_LINKABLE))
 666             /* todo: unnecessary? */
 667             /* && d_inode(cpg->dentry)->i_nlink == 1 */
 668             && cpg->bdst < cpg->bsrc
 669             && !au_ftest_cpup(cpg->flags, KEEPLINO))
 670                 au_xino_write(sb, cpg->bsrc, h_inode->i_ino, /*ino*/0);
 671                 /* ignore this error */
 672
 673         if (!err) {
 674                 force = 0;
 675                 if (isreg) {
 676                         force = !!cpg->len;
 677                         if (cpg->len == -1)
 678                                 force = !!i_size_read(h_inode);
 679                 }
 680                 au_fhsm_wrote(sb, cpg->bdst, force);
 681         }
 682
 683         if (do_dt)
 684                 au_dtime_revert(&dt);
 685         return err;
 686 }
 687
 688 static int au_do_ren_after_cpup(struct au_cp_generic *cpg, struct path *h_path)
 689 {
 690         int err;
 691         struct dentry *dentry, *h_dentry, *h_parent, *parent;
 692         struct inode *h_dir;
 693         aufs_bindex_t bdst;
 694
 695         dentry = cpg->dentry;
 696         bdst = cpg->bdst;
 697         h_dentry = au_h_dptr(dentry, bdst);
 698         if (!au_ftest_cpup(cpg->flags, OVERWRITE)) {
 699                 dget(h_dentry);
 700                 au_set_h_dptr(dentry, bdst, NULL);
 701                 err = au_lkup_neg(dentry, bdst, /*wh*/0);
 702                 if (!err)
 703                         h_path->dentry = dget(au_h_dptr(dentry, bdst));
 704                 au_set_h_dptr(dentry, bdst, h_dentry);
 705         } else {
 706                 err = 0;
 707                 parent = dget_parent(dentry);
 708                 h_parent = au_h_dptr(parent, bdst);
 709                 dput(parent);
 710                 h_path->dentry = vfsub_lkup_one(&dentry->d_name, h_parent);
 711                 if (IS_ERR(h_path->dentry))
 712                         err = PTR_ERR(h_path->dentry);
 713         }
 714         if (unlikely(err))
 715                 goto out;
 716
 717         h_parent = h_dentry->d_parent; /* dir inode is locked */
 718         h_dir = d_inode(h_parent);
 719         IMustLock(h_dir);
 720         AuDbg("%pd %pd\n", h_dentry, h_path->dentry);
 721         /* no delegation since it is just created */
 722         err = vfsub_rename(h_dir, h_dentry, h_dir, h_path, /*delegated*/NULL);
 723         dput(h_path->dentry);
 724
 725 out:
 726         return err;
 727 }
 728
 729 /*
 730  * copyup the @dentry from @bsrc to @bdst.
 731  * the caller must set the both of lower dentries.
 732  * @len is for truncating when it is -1 copyup the entire file.
 733  * in link/rename cases, @dst_parent may be different from the real one.
 734  * basic->bsrc can be larger than basic->bdst.
 735  */
 736 static int au_cpup_single(struct au_cp_generic *cpg, struct dentry *dst_parent)
 737 {
 738         int err, rerr;
 739         aufs_bindex_t old_ibtop;
 740         unsigned char isdir, plink;
 741         struct dentry *h_src, *h_dst, *h_parent;
 742         struct inode *dst_inode, *h_dir, *inode, *delegated, *src_inode;
 743         struct super_block *sb;
 744         struct au_branch *br;
 745         /* to reuduce stack size */
 746         struct {
 747                 struct au_dtime dt;
 748                 struct path h_path;
 749                 struct au_cpup_reg_attr h_src_attr;
 750         } *a;
 751
 752         err = -ENOMEM;
 753         a = kmalloc(sizeof(*a), GFP_NOFS);
 754         if (unlikely(!a))
 755                 goto out;
 756         a->h_src_attr.valid = 0;
 757
 758         sb = cpg->dentry->d_sb;
 759         br = au_sbr(sb, cpg->bdst);
 760         a->h_path.mnt = au_br_mnt(br);
 761         h_dst = au_h_dptr(cpg->dentry, cpg->bdst);
 762         h_parent = h_dst->d_parent; /* dir inode is locked */
 763         h_dir = d_inode(h_parent);
 764         IMustLock(h_dir);
 765
 766         h_src = au_h_dptr(cpg->dentry, cpg->bsrc);
 767         inode = d_inode(cpg->dentry);
 768
 769         if (!dst_parent)
 770                 dst_parent = dget_parent(cpg->dentry);
 771         else
 772                 dget(dst_parent);
 773
 774         plink = !!au_opt_test(au_mntflags(sb), PLINK);
 775         dst_inode = au_h_iptr(inode, cpg->bdst);
 776         if (dst_inode) {
 777                 if (unlikely(!plink)) {
 778                         err = -EIO;
 779                         AuIOErr("hi%lu(i%lu) exists on b%d "
 780                                 "but plink is disabled\n",
 781                                 dst_inode->i_ino, inode->i_ino, cpg->bdst);
 782                         goto out_parent;
 783                 }
 784
 785                 if (dst_inode->i_nlink) {
 786                         const int do_dt = au_ftest_cpup(cpg->flags, DTIME);
 787
 788                         h_src = au_plink_lkup(inode, cpg->bdst);
 789                         err = PTR_ERR(h_src);
 790                         if (IS_ERR(h_src))
 791                                 goto out_parent;
 792                         if (unlikely(d_is_negative(h_src))) {
 793                                 err = -EIO;
 794                                 AuIOErr("i%lu exists on b%d "
 795                                         "but not pseudo-linked\n",
 796                                         inode->i_ino, cpg->bdst);
 797                                 dput(h_src);
 798                                 goto out_parent;
 799                         }
 800
 801                         if (do_dt) {
 802                                 a->h_path.dentry = h_parent;
 803                                 au_dtime_store(&a->dt, dst_parent, &a->h_path);
 804                         }
 805
 806                         a->h_path.dentry = h_dst;
 807                         delegated = NULL;
 808                         err = vfsub_link(h_src, h_dir, &a->h_path, &delegated);
 809                         if (!err && au_ftest_cpup(cpg->flags, RENAME))
 810                                 err = au_do_ren_after_cpup(cpg, &a->h_path);
 811                         if (do_dt)
 812                                 au_dtime_revert(&a->dt);
 813                         if (unlikely(err == -EWOULDBLOCK)) {
 814                                 pr_warn("cannot retry for NFSv4 delegation"
 815                                         " for an internal link\n");
 816                                 iput(delegated);
 817                         }
 818                         dput(h_src);
 819                         goto out_parent;
 820                 } else
 821                         /* todo: cpup_wh_file? */
 822                         /* udba work */
 823                         au_update_ibrange(inode, /*do_put_zero*/1);
 824         }
 825
 826         isdir = S_ISDIR(inode->i_mode);
 827         old_ibtop = au_ibtop(inode);
 828         err = cpup_entry(cpg, dst_parent, &a->h_src_attr);
 829         if (unlikely(err))
 830                 goto out_rev;
 831         dst_inode = d_inode(h_dst);
 832         inode_lock_nested(dst_inode, AuLsc_I_CHILD2);
 833         /* todo: necessary? */
 834         /* au_pin_hdir_unlock(cpg->pin); */
 835
 836         err = cpup_iattr(cpg->dentry, cpg->bdst, h_src, &a->h_src_attr);
 837         if (unlikely(err)) {
 838                 /* todo: necessary? */
 839                 /* au_pin_hdir_relock(cpg->pin); */ /* ignore an error */
 840                 inode_unlock(dst_inode);
 841                 goto out_rev;
 842         }
 843
 844         if (cpg->bdst < old_ibtop) {
 845                 if (S_ISREG(inode->i_mode)) {
 846                         err = au_dy_iaop(inode, cpg->bdst, dst_inode);
 847                         if (unlikely(err)) {
 848                                 /* ignore an error */
 849                                 /* au_pin_hdir_relock(cpg->pin); */
 850                                 inode_unlock(dst_inode);
 851                                 goto out_rev;
 852                         }
 853                 }
 854                 au_set_ibtop(inode, cpg->bdst);
 855         } else
 856                 au_set_ibbot(inode, cpg->bdst);
 857         au_set_h_iptr(inode, cpg->bdst, au_igrab(dst_inode),
 858                       au_hi_flags(inode, isdir));
 859
 860         /* todo: necessary? */
 861         /* err = au_pin_hdir_relock(cpg->pin); */
 862         inode_unlock(dst_inode);
 863         if (unlikely(err))
 864                 goto out_rev;
 865
 866         src_inode = d_inode(h_src);
 867         if (!isdir
 868             && (src_inode->i_nlink > 1
 869                 || src_inode->i_state & I_LINKABLE)
 870             && plink)
 871                 au_plink_append(inode, cpg->bdst, h_dst);
 872
 873         if (au_ftest_cpup(cpg->flags, RENAME)) {
 874                 a->h_path.dentry = h_dst;
 875                 err = au_do_ren_after_cpup(cpg, &a->h_path);
 876         }
 877         if (!err)
 878                 goto out_parent; /* success */
 879
 880         /* revert */
 881 out_rev:
 882         a->h_path.dentry = h_parent;
 883         au_dtime_store(&a->dt, dst_parent, &a->h_path);
 884         a->h_path.dentry = h_dst;
 885         rerr = 0;
 886         if (d_is_positive(h_dst)) {
 887                 if (!isdir) {
 888                         /* no delegation since it is just created */
 889                         rerr = vfsub_unlink(h_dir, &a->h_path,
 890                                             /*delegated*/NULL, /*force*/0);
 891                 } else
 892                         rerr = vfsub_rmdir(h_dir, &a->h_path);
 893         }
 894         au_dtime_revert(&a->dt);
 895         if (rerr) {
 896                 AuIOErr("failed removing broken entry(%d, %d)\n", err, rerr);
 897                 err = -EIO;
 898         }
 899 out_parent:
 900         dput(dst_parent);
 901         au_delayed_kfree(a);
 902 out:
 903         return err;
 904 }
 905
 906 #if 0 /* reserved */
 907 struct au_cpup_single_args {
 908         int *errp;
 909         struct au_cp_generic *cpg;
 910         struct dentry *dst_parent;
 911 };
 912
 913 static void au_call_cpup_single(void *args)
 914 {
 915         struct au_cpup_single_args *a = args;
 916
 917         au_pin_hdir_acquire_nest(a->cpg->pin);
 918         *a->errp = au_cpup_single(a->cpg, a->dst_parent);
 919         au_pin_hdir_release(a->cpg->pin);
 920 }
 921 #endif
 922
 923 /*
 924  * prevent SIGXFSZ in copy-up.
 925  * testing CAP_MKNOD is for generic fs,
 926  * but CAP_FSETID is for xfs only, currently.
 927  */
 928 static int au_cpup_sio_test(struct au_pin *pin, umode_t mode)
 929 {
 930         int do_sio;
 931         struct super_block *sb;
 932         struct inode *h_dir;
 933
 934         do_sio = 0;
 935         sb = au_pinned_parent(pin)->d_sb;
 936         if (!au_wkq_test()
 937             && (!au_sbi(sb)->si_plink_maint_pid
 938                 || au_plink_maint(sb, AuLock_NOPLM))) {
 939                 switch (mode & S_IFMT) {
 940                 case S_IFREG:
 941                         /* no condition about RLIMIT_FSIZE and the file size */
 942                         do_sio = 1;
 943                         break;
 944                 case S_IFCHR:
 945                 case S_IFBLK:
 946                         do_sio = !capable(CAP_MKNOD);
 947                         break;
 948                 }
 949                 if (!do_sio)
 950                         do_sio = ((mode & (S_ISUID | S_ISGID))
 951                                   && !capable(CAP_FSETID));
 952                 /* this workaround may be removed in the future */
 953                 if (!do_sio) {
 954                         h_dir = au_pinned_h_dir(pin);
 955                         do_sio = h_dir->i_mode & S_ISVTX;
 956                 }
 957         }
 958
 959         return do_sio;
 960 }
 961
 962 #if 0 /* reserved */
 963 int au_sio_cpup_single(struct au_cp_generic *cpg, struct dentry *dst_parent)
 964 {
 965         int err, wkq_err;
 966         struct dentry *h_dentry;
 967
 968         h_dentry = au_h_dptr(cpg->dentry, cpg->bsrc);
 969         if (!au_cpup_sio_test(pin, d_inode(h_dentry)->i_mode))
 970                 err = au_cpup_single(cpg, dst_parent);
 971         else {
 972                 struct au_cpup_single_args args = {
 973                         .errp           = &err,
 974                         .cpg            = cpg,
 975                         .dst_parent     = dst_parent
 976                 };
 977                 wkq_err = au_wkq_wait(au_call_cpup_single, &args);
 978                 if (unlikely(wkq_err))
 979                         err = wkq_err;
 980         }
 981
 982         return err;
 983 }
 984 #endif
 985
 986 /*
 987  * copyup the @dentry from the first active lower branch to @bdst,
 988  * using au_cpup_single().
 989  */
 990 static int au_cpup_simple(struct au_cp_generic *cpg)
 991 {
 992         int err;
 993         unsigned int flags_orig;
 994         struct dentry *dentry;
 995
 996         AuDebugOn(cpg->bsrc < 0);
 997
 998         dentry = cpg->dentry;
 999         DiMustWriteLock(dentry);
1000
1001         err = au_lkup_neg(dentry, cpg->bdst, /*wh*/1);
1002         if (!err) {
1003                 flags_orig = cpg->flags;
1004                 au_fset_cpup(cpg->flags, RENAME);
1005                 err = au_cpup_single(cpg, NULL);
1006                 cpg->flags = flags_orig;
1007                 if (!err)
1008                         return 0; /* success */
1009
1010                 /* revert */
1011                 au_set_h_dptr(dentry, cpg->bdst, NULL);
1012                 au_set_dbtop(dentry, cpg->bsrc);
1013         }
1014
1015         return err;
1016 }
1017
1018 struct au_cpup_simple_args {
1019         int *errp;
1020         struct au_cp_generic *cpg;
1021 };
1022
1023 static void au_call_cpup_simple(void *args)
1024 {
1025         struct au_cpup_simple_args *a = args;
1026
1027         au_pin_hdir_acquire_nest(a->cpg->pin);
1028         *a->errp = au_cpup_simple(a->cpg);
1029         au_pin_hdir_release(a->cpg->pin);
1030 }
1031
1032 static int au_do_sio_cpup_simple(struct au_cp_generic *cpg)
1033 {
1034         int err, wkq_err;
1035         struct dentry *dentry, *parent;
1036         struct file *h_file;
1037         struct inode *h_dir;
1038
1039         dentry = cpg->dentry;
1040         h_file = NULL;
1041         if (au_ftest_cpup(cpg->flags, HOPEN)) {
1042                 AuDebugOn(cpg->bsrc < 0);
1043                 h_file = au_h_open_pre(dentry, cpg->bsrc, /*force_wr*/0);
1044                 err = PTR_ERR(h_file);
1045                 if (IS_ERR(h_file))
1046                         goto out;
1047         }
1048
1049         parent = dget_parent(dentry);
1050         h_dir = au_h_iptr(d_inode(parent), cpg->bdst);
1051         if (!au_test_h_perm_sio(h_dir, MAY_EXEC | MAY_WRITE)
1052             && !au_cpup_sio_test(cpg->pin, d_inode(dentry)->i_mode))
1053                 err = au_cpup_simple(cpg);
1054         else {
1055                 struct au_cpup_simple_args args = {
1056                         .errp           = &err,
1057                         .cpg            = cpg
1058                 };
1059                 wkq_err = au_wkq_wait(au_call_cpup_simple, &args);
1060                 if (unlikely(wkq_err))
1061                         err = wkq_err;
1062         }
1063
1064         dput(parent);
1065         if (h_file)
1066                 au_h_open_post(dentry, cpg->bsrc, h_file);
1067
1068 out:
1069         return err;
1070 }
1071
1072 int au_sio_cpup_simple(struct au_cp_generic *cpg)
1073 {
1074         aufs_bindex_t bsrc, bbot;
1075         struct dentry *dentry, *h_dentry;
1076
1077         if (cpg->bsrc < 0) {
1078                 dentry = cpg->dentry;
1079                 bbot = au_dbbot(dentry);
1080                 for (bsrc = cpg->bdst + 1; bsrc <= bbot; bsrc++) {
1081                         h_dentry = au_h_dptr(dentry, bsrc);
1082                         if (h_dentry) {
1083                                 AuDebugOn(d_is_negative(h_dentry));
1084                                 break;
1085                         }
1086                 }
1087                 AuDebugOn(bsrc > bbot);
1088                 cpg->bsrc = bsrc;
1089         }
1090         AuDebugOn(cpg->bsrc <= cpg->bdst);
1091         return au_do_sio_cpup_simple(cpg);
1092 }
1093
1094 int au_sio_cpdown_simple(struct au_cp_generic *cpg)
1095 {
1096         AuDebugOn(cpg->bdst <= cpg->bsrc);
1097         return au_do_sio_cpup_simple(cpg);
1098 }
1099
1100 /* ---------------------------------------------------------------------- */
1101
1102 /*
1103  * copyup the deleted file for writing.
1104  */
1105 static int au_do_cpup_wh(struct au_cp_generic *cpg, struct dentry *wh_dentry,
1106                          struct file *file)
1107 {
1108         int err;
1109         unsigned int flags_orig;
1110         aufs_bindex_t bsrc_orig;
1111         struct au_dinfo *dinfo;
1112         struct {
1113                 struct au_hdentry *hd;
1114                 struct dentry *h_dentry;
1115         } hdst, hsrc;
1116
1117         dinfo = au_di(cpg->dentry);
1118         AuRwMustWriteLock(&dinfo->di_rwsem);
1119
1120         bsrc_orig = cpg->bsrc;
1121         cpg->bsrc = dinfo->di_btop;
1122         hdst.hd = au_hdentry(dinfo, cpg->bdst);
1123         hdst.h_dentry = hdst.hd->hd_dentry;
1124         hdst.hd->hd_dentry = wh_dentry;
1125         dinfo->di_btop = cpg->bdst;
1126
1127         hsrc.h_dentry = NULL;
1128         if (file) {
1129                 hsrc.hd = au_hdentry(dinfo, cpg->bsrc);
1130                 hsrc.h_dentry = hsrc.hd->hd_dentry;
1131                 hsrc.hd->hd_dentry = au_hf_top(file)->f_path.dentry;
1132         }
1133         flags_orig = cpg->flags;
1134         cpg->flags = !AuCpup_DTIME;
1135         err = au_cpup_single(cpg, /*h_parent*/NULL);
1136         cpg->flags = flags_orig;
1137         if (file) {
1138                 if (!err)
1139                         err = au_reopen_nondir(file);
1140                 hsrc.hd->hd_dentry = hsrc.h_dentry;
1141         }
1142         hdst.hd->hd_dentry = hdst.h_dentry;
1143         dinfo->di_btop = cpg->bsrc;
1144         cpg->bsrc = bsrc_orig;
1145
1146         return err;
1147 }
1148
1149 static int au_cpup_wh(struct au_cp_generic *cpg, struct file *file)
1150 {
1151         int err;
1152         aufs_bindex_t bdst;
1153         struct au_dtime dt;
1154         struct dentry *dentry, *parent, *h_parent, *wh_dentry;
1155         struct au_branch *br;
1156         struct path h_path;
1157
1158         dentry = cpg->dentry;
1159         bdst = cpg->bdst;
1160         br = au_sbr(dentry->d_sb, bdst);
1161         parent = dget_parent(dentry);
1162         h_parent = au_h_dptr(parent, bdst);
1163         wh_dentry = au_whtmp_lkup(h_parent, br, &dentry->d_name);
1164         err = PTR_ERR(wh_dentry);
1165         if (IS_ERR(wh_dentry))
1166                 goto out;
1167
1168         h_path.dentry = h_parent;
1169         h_path.mnt = au_br_mnt(br);
1170         au_dtime_store(&dt, parent, &h_path);
1171         err = au_do_cpup_wh(cpg, wh_dentry, file);
1172         if (unlikely(err))
1173                 goto out_wh;
1174
1175         dget(wh_dentry);
1176         h_path.dentry = wh_dentry;
1177         if (!d_is_dir(wh_dentry)) {
1178                 /* no delegation since it is just created */
1179                 err = vfsub_unlink(d_inode(h_parent), &h_path,
1180                                    /*delegated*/NULL, /*force*/0);
1181         } else
1182                 err = vfsub_rmdir(d_inode(h_parent), &h_path);
1183         if (unlikely(err)) {
1184                 AuIOErr("failed remove copied-up tmp file %pd(%d)\n",
1185                         wh_dentry, err);
1186                 err = -EIO;
1187         }
1188         au_dtime_revert(&dt);
1189         au_set_hi_wh(d_inode(dentry), bdst, wh_dentry);
1190
1191 out_wh:
1192         dput(wh_dentry);
1193 out:
1194         dput(parent);
1195         return err;
1196 }
1197
1198 struct au_cpup_wh_args {
1199         int *errp;
1200         struct au_cp_generic *cpg;
1201         struct file *file;
1202 };
1203
1204 static void au_call_cpup_wh(void *args)
1205 {
1206         struct au_cpup_wh_args *a = args;
1207
1208         au_pin_hdir_acquire_nest(a->cpg->pin);
1209         *a->errp = au_cpup_wh(a->cpg, a->file);
1210         au_pin_hdir_release(a->cpg->pin);
1211 }
1212
1213 int au_sio_cpup_wh(struct au_cp_generic *cpg, struct file *file)
1214 {
1215         int err, wkq_err;
1216         aufs_bindex_t bdst;
1217         struct dentry *dentry, *parent, *h_orph, *h_parent;
1218         struct inode *dir, *h_dir, *h_tmpdir;
1219         struct au_wbr *wbr;
1220         struct au_pin wh_pin, *pin_orig;
1221
1222         dentry = cpg->dentry;
1223         bdst = cpg->bdst;
1224         parent = dget_parent(dentry);
1225         dir = d_inode(parent);
1226         h_orph = NULL;
1227         h_parent = NULL;
1228         h_dir = au_igrab(au_h_iptr(dir, bdst));
1229         h_tmpdir = h_dir;
1230         pin_orig = NULL;
1231         if (!h_dir->i_nlink) {
1232                 wbr = au_sbr(dentry->d_sb, bdst)->br_wbr;
1233                 h_orph = wbr->wbr_orph;
1234
1235                 h_parent = dget(au_h_dptr(parent, bdst));
1236                 au_set_h_dptr(parent, bdst, dget(h_orph));
1237                 h_tmpdir = d_inode(h_orph);
1238                 au_set_h_iptr(dir, bdst, au_igrab(h_tmpdir), /*flags*/0);
1239
1240                 inode_lock_nested(h_tmpdir, AuLsc_I_PARENT3);
1241                 /* todo: au_h_open_pre()? */
1242
1243                 pin_orig = cpg->pin;
1244                 au_pin_init(&wh_pin, dentry, bdst, AuLsc_DI_PARENT,
1245                             AuLsc_I_PARENT3, cpg->pin->udba, AuPin_DI_LOCKED);
1246                 cpg->pin = &wh_pin;
1247         }
1248
1249         if (!au_test_h_perm_sio(h_tmpdir, MAY_EXEC | MAY_WRITE)
1250             && !au_cpup_sio_test(cpg->pin, d_inode(dentry)->i_mode))
1251                 err = au_cpup_wh(cpg, file);
1252         else {
1253                 struct au_cpup_wh_args args = {
1254                         .errp   = &err,
1255                         .cpg    = cpg,
1256                         .file   = file
1257                 };
1258                 wkq_err = au_wkq_wait(au_call_cpup_wh, &args);
1259                 if (unlikely(wkq_err))
1260                         err = wkq_err;
1261         }
1262
1263         if (h_orph) {
1264                 inode_unlock(h_tmpdir);
1265                 /* todo: au_h_open_post()? */
1266                 au_set_h_iptr(dir, bdst, au_igrab(h_dir), /*flags*/0);
1267                 au_set_h_dptr(parent, bdst, h_parent);
1268                 AuDebugOn(!pin_orig);
1269                 cpg->pin = pin_orig;
1270         }
1271         iput(h_dir);
1272         dput(parent);
1273
1274         return err;
1275 }
1276
1277 /* ---------------------------------------------------------------------- */
1278
1279 /*
1280  * generic routine for both of copy-up and copy-down.
1281  */
1282 /* cf. revalidate function in file.c */
1283 int au_cp_dirs(struct dentry *dentry, aufs_bindex_t bdst,
1284                int (*cp)(struct dentry *dentry, aufs_bindex_t bdst,
1285                          struct au_pin *pin,
1286                          struct dentry *h_parent, void *arg),
1287                void *arg)
1288 {
1289         int err;
1290         struct au_pin pin;
1291         struct dentry *d, *parent, *h_parent, *real_parent, *h_dentry;
1292
1293         err = 0;
1294         parent = dget_parent(dentry);
1295         if (IS_ROOT(parent))
1296                 goto out;
1297
1298         au_pin_init(&pin, dentry, bdst, AuLsc_DI_PARENT2, AuLsc_I_PARENT2,
1299                     au_opt_udba(dentry->d_sb), AuPin_MNT_WRITE);
1300
1301         /* do not use au_dpage */
1302         real_parent = parent;
1303         while (1) {
1304                 dput(parent);
1305                 parent = dget_parent(dentry);
1306                 h_parent = au_h_dptr(parent, bdst);
1307                 if (h_parent)
1308                         goto out; /* success */
1309
1310                 /* find top dir which is necessary to cpup */
1311                 do {
1312                         d = parent;
1313                         dput(parent);
1314                         parent = dget_parent(d);
1315                         di_read_lock_parent3(parent, !AuLock_IR);
1316                         h_parent = au_h_dptr(parent, bdst);
1317                         di_read_unlock(parent, !AuLock_IR);
1318                 } while (!h_parent);
1319
1320                 if (d != real_parent)
1321                         di_write_lock_child3(d);
1322
1323                 /* somebody else might create while we were sleeping */
1324                 h_dentry = au_h_dptr(d, bdst);
1325                 if (!h_dentry || d_is_negative(h_dentry)) {
1326                         if (h_dentry)
1327                                 au_update_dbtop(d);
1328
1329                         au_pin_set_dentry(&pin, d);
1330                         err = au_do_pin(&pin);
1331                         if (!err) {
1332                                 err = cp(d, bdst, &pin, h_parent, arg);
1333                                 au_unpin(&pin);
1334                         }
1335                 }
1336
1337                 if (d != real_parent)
1338                         di_write_unlock(d);
1339                 if (unlikely(err))
1340                         break;
1341         }
1342
1343 out:
1344         dput(parent);
1345         return err;
1346 }
1347
1348 static int au_cpup_dir(struct dentry *dentry, aufs_bindex_t bdst,
1349                        struct au_pin *pin,
1350                        struct dentry *h_parent __maybe_unused,
1351                        void *arg __maybe_unused)
1352 {
1353         struct au_cp_generic cpg = {
1354                 .dentry = dentry,
1355                 .bdst   = bdst,
1356                 .bsrc   = -1,
1357                 .len    = 0,
1358                 .pin    = pin,
1359                 .flags  = AuCpup_DTIME
1360         };
1361         return au_sio_cpup_simple(&cpg);
1362 }
1363
1364 int au_cpup_dirs(struct dentry *dentry, aufs_bindex_t bdst)
1365 {
1366         return au_cp_dirs(dentry, bdst, au_cpup_dir, NULL);
1367 }
1368
1369 int au_test_and_cpup_dirs(struct dentry *dentry, aufs_bindex_t bdst)
1370 {
1371         int err;
1372         struct dentry *parent;
1373         struct inode *dir;
1374
1375         parent = dget_parent(dentry);
1376         dir = d_inode(parent);
1377         err = 0;
1378         if (au_h_iptr(dir, bdst))
1379                 goto out;
1380
1381         di_read_unlock(parent, AuLock_IR);
1382         di_write_lock_parent(parent);
1383         /* someone else might change our inode while we were sleeping */
1384         if (!au_h_iptr(dir, bdst))
1385                 err = au_cpup_dirs(dentry, bdst);
1386         di_downgrade_lock(parent, AuLock_IR);
1387
1388 out:
1389         dput(parent);
1390         return err;
1391 }