static struct dentry *lookup_whiteout(struct dentry *dentry) { char *whname; int bindex = -1, bstart = -1, bend = -1; struct dentry *parent, *hidden_parent, *wh_dentry; whname = alloc_whname(dentry->d_name.name, dentry->d_name.len); if (IS_ERR(whname)) return (void *)whname; parent = dget_parent(dentry); unionfs_lock_dentry(parent); bstart = dbstart(parent); bend = dbend(parent); wh_dentry = ERR_PTR(-ENOENT); for (bindex = bstart; bindex <= bend; bindex++) { hidden_parent = unionfs_lower_dentry_idx(parent, bindex); if (!hidden_parent) continue; wh_dentry = lookup_one_len(whname, hidden_parent, dentry->d_name.len + UNIONFS_WHLEN); if (IS_ERR(wh_dentry)) continue; if (wh_dentry->d_inode) break; dput(wh_dentry); wh_dentry = ERR_PTR(-ENOENT); } unionfs_unlock_dentry(parent); dput(parent); kfree(whname); return wh_dentry; }
static struct dentry *lookup_whiteout(struct dentry *dentry) { char *whname; int bindex = -1, bstart = -1, bend = -1; struct dentry *parent, *hidden_parent, *wh_dentry; whname = alloc_whname(dentry->d_name.name, dentry->d_name.len); if (IS_ERR(whname)) return (void *)whname; parent = GET_PARENT(dentry); lock_dentry(parent); bstart = dbstart(parent); bend = dbend(parent); wh_dentry = ERR_PTR(-ENOENT); for (bindex = bstart; bindex <= bend; bindex++) { hidden_parent = dtohd_index(parent, bindex); if (!hidden_parent) continue; wh_dentry = LOOKUP_ONE_LEN(whname, hidden_parent, dentry->d_name.len + WHLEN); if (IS_ERR(wh_dentry)) continue; if (wh_dentry->d_inode) break; DPUT(wh_dentry); wh_dentry = ERR_PTR(-ENOENT); } unlock_dentry(parent); DPUT(parent); KFREE(whname); return wh_dentry; }
static int do_rename(struct inode *old_dir, struct dentry *old_dentry, struct inode *new_dir, struct dentry *new_dentry, int bindex, struct dentry **wh_old) { int err = 0; struct dentry *hidden_old_dentry; struct dentry *hidden_new_dentry; struct dentry *hidden_old_dir_dentry; struct dentry *hidden_new_dir_dentry; struct dentry *hidden_wh_dentry; struct dentry *hidden_wh_dir_dentry; char *wh_name = NULL; print_entry(" bindex=%d", bindex); fist_print_dentry("IN: do_rename, old_dentry", old_dentry); fist_print_dentry("IN: do_rename, new_dentry", new_dentry); fist_dprint(7, "do_rename for bindex = %d\n", bindex); hidden_new_dentry = dtohd_index(new_dentry, bindex); hidden_old_dentry = dtohd_index(old_dentry, bindex); if (!hidden_new_dentry) { hidden_new_dentry = create_parents(new_dentry->d_parent->d_inode, new_dentry, bindex); if (IS_ERR(hidden_new_dentry)) { fist_dprint(7, "error creating directory tree for rename, bindex = %d\n", bindex); err = PTR_ERR(hidden_new_dentry); goto out; } } wh_name = alloc_whname(new_dentry->d_name.name, new_dentry->d_name.len); if (IS_ERR(wh_name)) { err = PTR_ERR(wh_name); goto out; } hidden_wh_dentry = LOOKUP_ONE_LEN(wh_name, hidden_new_dentry->d_parent, new_dentry->d_name.len + WHLEN); if (IS_ERR(hidden_wh_dentry)) { err = PTR_ERR(hidden_wh_dentry); goto out; } if (hidden_wh_dentry->d_inode) { /* get rid of the whiteout that is existing */ if (hidden_new_dentry->d_inode) { printk(KERN_WARNING "Both a whiteout and a dentry exist when doing a rename!\n"); err = -EIO; DPUT(hidden_wh_dentry); goto out; } hidden_wh_dir_dentry = lock_parent(hidden_wh_dentry); if (!(err = is_robranch_super(old_dentry->d_sb, bindex))) { err = vfs_unlink(hidden_wh_dir_dentry->d_inode, hidden_wh_dentry); } DPUT(hidden_wh_dentry); unlock_dir(hidden_wh_dir_dentry); if (err) goto out; } else DPUT(hidden_wh_dentry); DGET(hidden_old_dentry); hidden_old_dir_dentry = GET_PARENT(hidden_old_dentry); hidden_new_dir_dentry = GET_PARENT(hidden_new_dentry); lock_rename(hidden_old_dir_dentry, hidden_new_dir_dentry); err = is_robranch_super(old_dentry->d_sb, bindex); if (err) goto out_unlock; /* ready to whiteout for old_dentry. caller will create the actual whiteout, and must dput(*wh_old) */ if (wh_old) { char *whname; whname = alloc_whname(old_dentry->d_name.name, old_dentry->d_name.len); err = PTR_ERR(whname); if (IS_ERR(whname)) goto out_unlock; *wh_old = LOOKUP_ONE_LEN(whname, hidden_old_dir_dentry, old_dentry->d_name.len + WHLEN); KFREE(whname); err = PTR_ERR(*wh_old); if (IS_ERR(*wh_old)) { *wh_old = NULL; goto out_unlock; } } fist_print_dentry("NEWBEF", new_dentry); fist_print_dentry("OLDBEF", old_dentry); err = vfs_rename(hidden_old_dir_dentry->d_inode, hidden_old_dentry, hidden_new_dir_dentry->d_inode, hidden_new_dentry); fist_print_dentry("NEWAFT", new_dentry); fist_print_dentry("OLDAFT", old_dentry); out_unlock: unlock_rename(hidden_old_dir_dentry, hidden_new_dir_dentry); DPUT(hidden_old_dir_dentry); DPUT(hidden_new_dir_dentry); DPUT(hidden_old_dentry); out: if (!err) { /* Fixup the newdentry. */ if (bindex < dbstart(new_dentry)) set_dbstart(new_dentry, bindex); else if (bindex > dbend(new_dentry)) set_dbend(new_dentry, bindex); } KFREE(wh_name); fist_print_dentry("OUT: do_rename, old_dentry", old_dentry); fist_print_dentry("OUT: do_rename, new_dentry", new_dentry); print_exit_status(err); return err; }
struct dentry *unionfs_lookup_backend(struct dentry *dentry, struct nameidata *nd, int lookupmode) { int err = 0; struct dentry *hidden_dentry = NULL; struct dentry *wh_hidden_dentry = NULL; struct dentry *hidden_dir_dentry = NULL; struct dentry *parent_dentry = NULL; int bindex, bstart, bend, bopaque; int dentry_count = 0; /* Number of positive dentries. */ int first_dentry_offset = -1; struct dentry *first_hidden_dentry = NULL; struct vfsmount *first_hidden_mnt = NULL; int locked_parent = 0; int locked_child = 0; int opaque; char *whname = NULL; const char *name; int namelen; /* We should already have a lock on this dentry in the case of a * partial lookup, or a revalidation. Otherwise it is returned from * new_dentry_private_data already locked. */ if (lookupmode == INTERPOSE_PARTIAL || lookupmode == INTERPOSE_REVAL || lookupmode == INTERPOSE_REVAL_NEG) verify_locked(dentry); else { BUG_ON(UNIONFS_D(dentry) != NULL); locked_child = 1; } if (lookupmode != INTERPOSE_PARTIAL) if ((err = new_dentry_private_data(dentry))) goto out; /* must initialize dentry operations */ dentry->d_op = &unionfs_dops; parent_dentry = dget_parent(dentry); /* We never partial lookup the root directory. */ if (parent_dentry != dentry) { unionfs_lock_dentry(parent_dentry); locked_parent = 1; } else { dput(parent_dentry); parent_dentry = NULL; goto out; } name = dentry->d_name.name; namelen = dentry->d_name.len; /* No dentries should get created for possible whiteout names. */ if (!is_validname(name)) { err = -EPERM; goto out_free; } /* Now start the actual lookup procedure. */ bstart = dbstart(parent_dentry); bend = dbend(parent_dentry); bopaque = dbopaque(parent_dentry); BUG_ON(bstart < 0); /* It would be ideal if we could convert partial lookups to only have * to do this work when they really need to. It could probably improve * performance quite a bit, and maybe simplify the rest of the code. */ if (lookupmode == INTERPOSE_PARTIAL) { bstart++; if ((bopaque != -1) && (bopaque < bend)) bend = bopaque; } for (bindex = bstart; bindex <= bend; bindex++) { hidden_dentry = unionfs_lower_dentry_idx(dentry, bindex); if (lookupmode == INTERPOSE_PARTIAL && hidden_dentry) continue; BUG_ON(hidden_dentry != NULL); hidden_dir_dentry = unionfs_lower_dentry_idx(parent_dentry, bindex); /* if the parent hidden dentry does not exist skip this */ if (!(hidden_dir_dentry && hidden_dir_dentry->d_inode)) continue; /* also skip it if the parent isn't a directory. */ if (!S_ISDIR(hidden_dir_dentry->d_inode->i_mode)) continue; /* Reuse the whiteout name because its value doesn't change. */ if (!whname) { whname = alloc_whname(name, namelen); if (IS_ERR(whname)) { err = PTR_ERR(whname); goto out_free; } } /* check if whiteout exists in this branch: lookup .wh.foo */ wh_hidden_dentry = lookup_one_len(whname, hidden_dir_dentry, namelen + UNIONFS_WHLEN); if (IS_ERR(wh_hidden_dentry)) { dput(first_hidden_dentry); mntput(first_hidden_mnt); err = PTR_ERR(wh_hidden_dentry); goto out_free; } if (wh_hidden_dentry->d_inode) { /* We found a whiteout so lets give up. */ if (S_ISREG(wh_hidden_dentry->d_inode->i_mode)) { set_dbend(dentry, bindex); set_dbopaque(dentry, bindex); dput(wh_hidden_dentry); break; } err = -EIO; printk(KERN_NOTICE "EIO: Invalid whiteout entry type" " %d.\n", wh_hidden_dentry->d_inode->i_mode); dput(wh_hidden_dentry); dput(first_hidden_dentry); mntput(first_hidden_mnt); goto out_free; } dput(wh_hidden_dentry); wh_hidden_dentry = NULL; /* Now do regular lookup; lookup foo */ nd->dentry = unionfs_lower_dentry_idx(dentry, bindex); /* FIXME: fix following line for mount point crossing */ nd->mnt = unionfs_lower_mnt_idx(parent_dentry, bindex); hidden_dentry = lookup_one_len_nd(name, hidden_dir_dentry, namelen, nd); if (IS_ERR(hidden_dentry)) { dput(first_hidden_dentry); mntput(first_hidden_mnt); err = PTR_ERR(hidden_dentry); goto out_free; } /* Store the first negative dentry specially, because if they * are all negative we need this for future creates. */ if (!hidden_dentry->d_inode) { if (!first_hidden_dentry && (dbstart(dentry) == -1)) { first_hidden_dentry = hidden_dentry; /* FIXME: following line needs to be changed * to allow mountpoint crossing */ first_hidden_mnt = mntget( unionfs_lower_mnt_idx(parent_dentry, bindex)); first_dentry_offset = bindex; } else dput(hidden_dentry); continue; } /* number of positive dentries */ dentry_count++; /* store underlying dentry */ if (dbstart(dentry) == -1) set_dbstart(dentry, bindex); unionfs_set_lower_dentry_idx(dentry, bindex, hidden_dentry); /* FIXME: the following line needs to get fixed to allow * mountpoint crossing */ unionfs_set_lower_mnt_idx(dentry, bindex, mntget(unionfs_lower_mnt_idx(parent_dentry, bindex))); set_dbend(dentry, bindex); /* update parent directory's atime with the bindex */ fsstack_copy_attr_atime(parent_dentry->d_inode, hidden_dir_dentry->d_inode); /* We terminate file lookups here. */ if (!S_ISDIR(hidden_dentry->d_inode->i_mode)) { if (lookupmode == INTERPOSE_PARTIAL) continue; if (dentry_count == 1) goto out_positive; /* This can only happen with mixed D-*-F-* */ BUG_ON(!S_ISDIR(unionfs_lower_dentry(dentry)->d_inode->i_mode)); continue; } opaque = is_opaque_dir(dentry, bindex); if (opaque < 0) { dput(first_hidden_dentry); mntput(first_hidden_mnt); err = opaque; goto out_free; } else if (opaque) { set_dbend(dentry, bindex); set_dbopaque(dentry, bindex); break; } } if (dentry_count) goto out_positive; else goto out_negative; out_negative: if (lookupmode == INTERPOSE_PARTIAL) goto out; /* If we've only got negative dentries, then use the leftmost one. */ if (lookupmode == INTERPOSE_REVAL) { if (dentry->d_inode) UNIONFS_I(dentry->d_inode)->stale = 1; goto out; } /* This should only happen if we found a whiteout. */ if (first_dentry_offset == -1) { nd->dentry = dentry; /* FIXME: fix following line for mount point crossing */ nd->mnt = unionfs_lower_mnt_idx(parent_dentry, bindex); first_hidden_dentry = lookup_one_len_nd(name, hidden_dir_dentry, namelen, nd); first_dentry_offset = bindex; if (IS_ERR(first_hidden_dentry)) { err = PTR_ERR(first_hidden_dentry); goto out; } /* FIXME: the following line needs to be changed to allow * mountpoint crossing */ first_hidden_mnt = mntget(unionfs_lower_mnt_idx(dentry, bindex)); } unionfs_set_lower_dentry_idx(dentry, first_dentry_offset, first_hidden_dentry); unionfs_set_lower_mnt_idx(dentry, first_dentry_offset, first_hidden_mnt); set_dbstart(dentry, first_dentry_offset); set_dbend(dentry, first_dentry_offset); if (lookupmode == INTERPOSE_REVAL_NEG) BUG_ON(dentry->d_inode != NULL); else d_add(dentry, NULL); goto out; /* This part of the code is for positive dentries. */ out_positive: BUG_ON(dentry_count <= 0); /* If we're holding onto the first negative dentry & corresponding * vfsmount - throw it out. */ dput(first_hidden_dentry); mntput(first_hidden_mnt); /* Partial lookups need to reinterpose, or throw away older negs. */ if (lookupmode == INTERPOSE_PARTIAL) { if (dentry->d_inode) { unionfs_reinterpose(dentry); goto out; } /* This somehow turned positive, so it is as if we had a * negative revalidation. */ lookupmode = INTERPOSE_REVAL_NEG; update_bstart(dentry); bstart = dbstart(dentry); bend = dbend(dentry); } err = unionfs_interpose(dentry, dentry->d_sb, lookupmode); if (err) goto out_drop; goto out; out_drop: d_drop(dentry); out_free: /* should dput all the underlying dentries on error condition */ bstart = dbstart(dentry); if (bstart >= 0) { bend = dbend(dentry); for (bindex = bstart; bindex <= bend; bindex++) { dput(unionfs_lower_dentry_idx(dentry, bindex)); mntput(unionfs_lower_mnt_idx(dentry, bindex)); } } kfree(UNIONFS_D(dentry)->lower_paths); UNIONFS_D(dentry)->lower_paths = NULL; set_dbstart(dentry, -1); set_dbend(dentry, -1); out: if (!err && UNIONFS_D(dentry)) { BUG_ON(dbend(dentry) > UNIONFS_D(dentry)->bcount); BUG_ON(dbend(dentry) > sbmax(dentry->d_sb)); BUG_ON(dbstart(dentry) < 0); } kfree(whname); if (locked_parent) unionfs_unlock_dentry(parent_dentry); dput(parent_dentry); if (locked_child) unionfs_unlock_dentry(dentry); return ERR_PTR(err); }
struct dentry *unionfs_lookup_backend(struct dentry *dentry, int lookupmode) { int err = 0; struct dentry *hidden_dentry = NULL; struct dentry *wh_hidden_dentry = NULL; struct dentry *hidden_dir_dentry = NULL; struct dentry *parent_dentry = NULL; int bindex, bstart, bend, bopaque; int dentry_count = 0; /* Number of positive dentries. */ int first_dentry_offset = -1; struct dentry *first_hidden_dentry = NULL; int locked_parent = 0; int locked_child = 0; int opaque; char *whname = NULL; const char *name; int namelen; print_entry("mode = %d", lookupmode); /* We should already have a lock on this dentry in the case of a * partial lookup, or a revalidation. Otherwise it is returned from * new_dentry_private_data already locked. */ if (lookupmode == INTERPOSE_PARTIAL || lookupmode == INTERPOSE_REVAL || lookupmode == INTERPOSE_REVAL_NEG) { verify_locked(dentry); } else { BUG_ON(dtopd_nocheck(dentry) != NULL); locked_child = 1; } if (lookupmode != INTERPOSE_PARTIAL) if ((err = new_dentry_private_data(dentry))) goto out; /* must initialize dentry operations */ dentry->d_op = &unionfs_dops; parent_dentry = GET_PARENT(dentry); /* We never partial lookup the root directory. */ if (parent_dentry != dentry) { lock_dentry(parent_dentry); locked_parent = 1; } else { DPUT(parent_dentry); parent_dentry = NULL; goto out; } fist_print_dentry("IN unionfs_lookup (parent)", parent_dentry); fist_print_dentry("IN unionfs_lookup (child)", dentry); name = dentry->d_name.name; namelen = dentry->d_name.len; /* No dentries should get created for possible whiteout names. */ if (!is_validname(name)) { err = -EPERM; goto out_free; } /* Now start the actual lookup procedure. */ bstart = dbstart(parent_dentry); bend = dbend(parent_dentry); bopaque = dbopaque(parent_dentry); BUG_ON(bstart < 0); /* It would be ideal if we could convert partial lookups to only have * to do this work when they really need to. It could probably improve * performance quite a bit, and maybe simplify the rest of the code. */ if (lookupmode == INTERPOSE_PARTIAL) { bstart++; if ((bopaque != -1) && (bopaque < bend)) bend = bopaque; } fist_dprint(8, "bstart = %d, bend = %d\n", bstart, bend); for (bindex = bstart; bindex <= bend; bindex++) { hidden_dentry = dtohd_index(dentry, bindex); if (lookupmode == INTERPOSE_PARTIAL && hidden_dentry) continue; BUG_ON(hidden_dentry != NULL); hidden_dir_dentry = dtohd_index(parent_dentry, bindex); /* if the parent hidden dentry does not exist skip this */ if (!(hidden_dir_dentry && hidden_dir_dentry->d_inode)) continue; /* also skip it if the parent isn't a directory. */ if (!S_ISDIR(hidden_dir_dentry->d_inode->i_mode)) continue; /* Reuse the whiteout name because its value doesn't change. */ if (!whname) { whname = alloc_whname(name, namelen); if (IS_ERR(whname)) { err = PTR_ERR(whname); goto out_free; } } /* check if whiteout exists in this branch: lookup .wh.foo */ wh_hidden_dentry = LOOKUP_ONE_LEN(whname, hidden_dir_dentry, namelen + WHLEN); if (IS_ERR(wh_hidden_dentry)) { DPUT(first_hidden_dentry); err = PTR_ERR(wh_hidden_dentry); goto out_free; } if (wh_hidden_dentry->d_inode) { /* We found a whiteout so lets give up. */ fist_dprint(8, "whiteout found in %d\n", bindex); if (S_ISREG(wh_hidden_dentry->d_inode->i_mode)) { set_dbend(dentry, bindex); set_dbopaque(dentry, bindex); DPUT(wh_hidden_dentry); break; } err = -EIO; printk(KERN_NOTICE "EIO: Invalid whiteout entry type" " %d.\n", wh_hidden_dentry->d_inode->i_mode); DPUT(wh_hidden_dentry); DPUT(first_hidden_dentry); goto out_free; } DPUT(wh_hidden_dentry); wh_hidden_dentry = NULL; /* Now do regular lookup; lookup foo */ hidden_dentry = LOOKUP_ONE_LEN(name, hidden_dir_dentry, namelen); fist_print_generic_dentry("hidden result", hidden_dentry); if (IS_ERR(hidden_dentry)) { DPUT(first_hidden_dentry); err = PTR_ERR(hidden_dentry); goto out_free; } /* Store the first negative dentry specially, because if they * are all negative we need this for future creates. */ if (!hidden_dentry->d_inode) { if (!first_hidden_dentry && (dbstart(dentry) == -1)) { first_hidden_dentry = hidden_dentry; first_dentry_offset = bindex; } else { DPUT(hidden_dentry); } continue; } /* number of positive dentries */ dentry_count++; /* store underlying dentry */ if (dbstart(dentry) == -1) set_dbstart(dentry, bindex); set_dtohd_index(dentry, bindex, hidden_dentry); set_dbend(dentry, bindex); /* update parent directory's atime with the bindex */ fist_copy_attr_atime(parent_dentry->d_inode, hidden_dir_dentry->d_inode); /* We terminate file lookups here. */ if (!S_ISDIR(hidden_dentry->d_inode->i_mode)) { if (lookupmode == INTERPOSE_PARTIAL) continue; if (dentry_count == 1) goto out_positive; /* This can only happen with mixed D-*-F-* */ BUG_ON(!S_ISDIR(dtohd(dentry)->d_inode->i_mode)); continue; } opaque = is_opaque_dir(dentry, bindex); if (opaque < 0) { DPUT(first_hidden_dentry); err = opaque; goto out_free; } if (opaque) { set_dbend(dentry, bindex); set_dbopaque(dentry, bindex); break; } } if (dentry_count) goto out_positive; else goto out_negative; out_negative: if (lookupmode == INTERPOSE_PARTIAL) goto out; /* If we've only got negative dentries, then use the leftmost one. */ if (lookupmode == INTERPOSE_REVAL) { if (dentry->d_inode) { itopd(dentry->d_inode)->uii_stale = 1; } goto out; } /* This should only happen if we found a whiteout. */ if (first_dentry_offset == -1) { first_hidden_dentry = LOOKUP_ONE_LEN(name, hidden_dir_dentry, namelen); first_dentry_offset = bindex; if (IS_ERR(first_hidden_dentry)) { err = PTR_ERR(first_hidden_dentry); goto out; } } set_dtohd_index(dentry, first_dentry_offset, first_hidden_dentry); set_dbstart(dentry, first_dentry_offset); set_dbend(dentry, first_dentry_offset); if (lookupmode == INTERPOSE_REVAL_NEG) BUG_ON(dentry->d_inode != NULL); else d_add(dentry, NULL); goto out; /* This part of the code is for positive dentries. */ out_positive: BUG_ON(dentry_count <= 0); /* If we're holding onto the first negative dentry throw it out. */ DPUT(first_hidden_dentry); /* Partial lookups need to reinterpose, or throw away older negs. */ if (lookupmode == INTERPOSE_PARTIAL) { if (dentry->d_inode) { unionfs_reinterpose(dentry); goto out; } /* This somehow turned positive, so it is as if we had a * negative revalidation. */ lookupmode = INTERPOSE_REVAL_NEG; update_bstart(dentry); bstart = dbstart(dentry); bend = dbend(dentry); } err = unionfs_interpose(dentry, dentry->d_sb, lookupmode); if (err) goto out_drop; fist_checkinode(dentry->d_inode, "unionfs_lookup OUT: child"); fist_checkinode(parent_dentry->d_inode, "unionfs_lookup OUT: dir"); goto out; out_drop: d_drop(dentry); out_free: /* should dput all the underlying dentries on error condition */ bstart = dbstart(dentry); if (bstart >= 0) { bend = dbend(dentry); for (bindex = bstart; bindex <= bend; bindex++) DPUT(dtohd_index(dentry, bindex)); } KFREE(dtohd_ptr(dentry)); dtohd_ptr(dentry) = NULL; set_dbstart(dentry, -1); set_dbend(dentry, -1); out: if (!err && dtopd(dentry)) { BUG_ON(dbend(dentry) > dtopd(dentry)->udi_bcount); BUG_ON(dbend(dentry) > sbmax(dentry->d_sb)); BUG_ON(dbstart(dentry) < 0); } KFREE(whname); fist_print_dentry("OUT unionfs_lookup (parent)", parent_dentry); fist_print_dentry("OUT unionfs_lookup (child)", dentry); if (locked_parent) unlock_dentry(parent_dentry); DPUT(parent_dentry); if (locked_child) unlock_dentry(dentry); print_exit_status(err); return ERR_PTR(err); }
static int do_rename(struct inode *old_dir, struct dentry *old_dentry, struct inode *new_dir, struct dentry *new_dentry, int bindex, struct dentry **wh_old) { int err = 0; struct dentry *hidden_old_dentry; struct dentry *hidden_new_dentry; struct dentry *hidden_old_dir_dentry; struct dentry *hidden_new_dir_dentry; struct dentry *hidden_wh_dentry; struct dentry *hidden_wh_dir_dentry; char *wh_name = NULL; hidden_new_dentry = unionfs_lower_dentry_idx(new_dentry, bindex); hidden_old_dentry = unionfs_lower_dentry_idx(old_dentry, bindex); if (!hidden_new_dentry) { hidden_new_dentry = create_parents(new_dentry->d_parent->d_inode, new_dentry, bindex); if (IS_ERR(hidden_new_dentry)) { printk(KERN_DEBUG "error creating directory tree for" " rename, bindex = %d, err = %ld\n", bindex, PTR_ERR(hidden_new_dentry)); err = PTR_ERR(hidden_new_dentry); goto out; } } wh_name = alloc_whname(new_dentry->d_name.name, new_dentry->d_name.len); if (IS_ERR(wh_name)) { err = PTR_ERR(wh_name); goto out; } hidden_wh_dentry = lookup_one_len(wh_name, hidden_new_dentry->d_parent, new_dentry->d_name.len + UNIONFS_WHLEN); if (IS_ERR(hidden_wh_dentry)) { err = PTR_ERR(hidden_wh_dentry); goto out; } if (hidden_wh_dentry->d_inode) { /* get rid of the whiteout that is existing */ if (hidden_new_dentry->d_inode) { printk(KERN_WARNING "Both a whiteout and a dentry" " exist when doing a rename!\n"); err = -EIO; dput(hidden_wh_dentry); goto out; } hidden_wh_dir_dentry = lock_parent(hidden_wh_dentry); if (!(err = is_robranch_super(old_dentry->d_sb, bindex))) err = vfs_unlink(hidden_wh_dir_dentry->d_inode, hidden_wh_dentry); dput(hidden_wh_dentry); unlock_dir(hidden_wh_dir_dentry); if (err) goto out; } else dput(hidden_wh_dentry); dget(hidden_old_dentry); hidden_old_dir_dentry = dget_parent(hidden_old_dentry); hidden_new_dir_dentry = dget_parent(hidden_new_dentry); lock_rename(hidden_old_dir_dentry, hidden_new_dir_dentry); err = is_robranch_super(old_dentry->d_sb, bindex); if (err) goto out_unlock; /* ready to whiteout for old_dentry. caller will create the actual * whiteout, and must dput(*wh_old) */ if (wh_old) { char *whname; whname = alloc_whname(old_dentry->d_name.name, old_dentry->d_name.len); err = PTR_ERR(whname); if (IS_ERR(whname)) goto out_unlock; *wh_old = lookup_one_len(whname, hidden_old_dir_dentry, old_dentry->d_name.len + UNIONFS_WHLEN); kfree(whname); err = PTR_ERR(*wh_old); if (IS_ERR(*wh_old)) { *wh_old = NULL; goto out_unlock; } } err = vfs_rename(hidden_old_dir_dentry->d_inode, hidden_old_dentry, hidden_new_dir_dentry->d_inode, hidden_new_dentry); out_unlock: unlock_rename(hidden_old_dir_dentry, hidden_new_dir_dentry); dput(hidden_old_dir_dentry); dput(hidden_new_dir_dentry); dput(hidden_old_dentry); out: if (!err) { /* Fixup the newdentry. */ if (bindex < dbstart(new_dentry)) set_dbstart(new_dentry, bindex); else if (bindex > dbend(new_dentry)) set_dbend(new_dentry, bindex); } kfree(wh_name); return err; }
static int unionfs_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev) { int err = 0; struct dentry *hidden_dentry = NULL, *whiteout_dentry = NULL; struct dentry *hidden_parent_dentry = NULL; int bindex = 0, bstart; char *name = NULL; int whiteout_unlinked = 0; print_entry_location(); lock_dentry(dentry); fist_print_dentry("IN unionfs_mknod", dentry); bstart = dbstart(dentry); hidden_dentry = dtohd(dentry); // check if whiteout exists in this branch, i.e. lookup .wh.foo first name = alloc_whname(dentry->d_name.name, dentry->d_name.len); if (IS_ERR(name)) { err = PTR_ERR(name); goto out; } whiteout_dentry = LOOKUP_ONE_LEN(name, hidden_dentry->d_parent, dentry->d_name.len + WHLEN); if (IS_ERR(whiteout_dentry)) { err = PTR_ERR(whiteout_dentry); goto out; } if (!whiteout_dentry->d_inode) { DPUT(whiteout_dentry); whiteout_dentry = NULL; } else { /* found .wh.foo, unlink it */ hidden_parent_dentry = lock_parent(whiteout_dentry); //found a.wh.foo entry, remove it then do vfs_mkdir if (!(err = is_robranch_super(dentry->d_sb, bstart))) err = vfs_unlink(hidden_parent_dentry->d_inode, whiteout_dentry); DPUT(whiteout_dentry); unlock_dir(hidden_parent_dentry); if (err) { if (!IS_COPYUP_ERR(err)) goto out; bstart--; } else { whiteout_unlinked = 1; } } for (bindex = bstart; bindex >= 0; bindex--) { hidden_dentry = dtohd_index(dentry, bindex); if (!hidden_dentry) { hidden_dentry = create_parents(dir, dentry, bindex); if (!hidden_dentry || IS_ERR(hidden_dentry)) { fist_dprint(8, "hidden dentry NULL for bindex = %d\n", bindex); continue; } } hidden_parent_dentry = lock_parent(hidden_dentry); if (IS_ERR(hidden_parent_dentry)) { err = PTR_ERR(hidden_parent_dentry); goto out; } if (!(err = is_robranch_super(dentry->d_sb, bindex))) { err = vfs_mknod(hidden_parent_dentry->d_inode, hidden_dentry, mode, dev); } /* XXX this could potentially return a negative hidden_dentry! */ if (err || !hidden_dentry->d_inode) { unlock_dir(hidden_parent_dentry); /* break out of for, if error was NOT -EROFS */ if (!IS_COPYUP_ERR(err)) break; } else { err = unionfs_interpose(dentry, dir->i_sb, 0); if (!err) { fist_copy_attr_timesizes(dir, hidden_parent_dentry-> d_inode); /* update number of links on parent directory */ dir->i_nlink = get_nlinks(dir); } unlock_dir(hidden_parent_dentry); break; } } out: if (!dentry->d_inode) d_drop(dentry); if (name) { KFREE(name); } fist_print_dentry("OUT unionfs_mknod :", dentry); unlock_dentry(dentry); print_exit_status(err); return err; }
static int unionfs_mkdir(struct inode *parent, struct dentry *dentry, int mode) { int err = 0; struct dentry *hidden_dentry = NULL, *whiteout_dentry = NULL; struct dentry *hidden_parent_dentry = NULL; int bindex = 0, bstart; char *name = NULL; int whiteout_unlinked = 0; uid_t saved_uid = current->fsuid; gid_t saved_gid = current->fsgid; print_entry_location(); lock_dentry(dentry); fist_print_dentry("IN unionfs_mkdir", dentry); bstart = dbstart(dentry); hidden_dentry = dtohd(dentry); // check if whiteout exists in this branch, i.e. lookup .wh.foo first name = alloc_whname(dentry->d_name.name, dentry->d_name.len); if (IS_ERR(name)) { err = PTR_ERR(name); goto out; } whiteout_dentry = LOOKUP_ONE_LEN(name, hidden_dentry->d_parent, dentry->d_name.len + WHLEN); if (IS_ERR(whiteout_dentry)) { err = PTR_ERR(whiteout_dentry); goto out; } if (!whiteout_dentry->d_inode) { DPUT(whiteout_dentry); whiteout_dentry = NULL; } else { hidden_parent_dentry = lock_parent(whiteout_dentry); /* Set the uid and gid to trick the fs into allowing us to create * the file */ current->fsuid = hidden_parent_dentry->d_inode->i_uid; current->fsgid = hidden_parent_dentry->d_inode->i_gid; //found a.wh.foo entry, remove it then do vfs_mkdir if (!(err = is_robranch_super(dentry->d_sb, bstart))) { err = vfs_unlink(hidden_parent_dentry->d_inode, whiteout_dentry); } DPUT(whiteout_dentry); current->fsuid = saved_uid; current->fsgid = saved_gid; unlock_dir(hidden_parent_dentry); if (err) { /* exit if the error returned was NOT -EROFS */ if (!IS_COPYUP_ERR(err)) goto out; bstart--; } else { whiteout_unlinked = 1; } } for (bindex = bstart; bindex >= 0; bindex--) { hidden_dentry = dtohd_index(dentry, bindex); if (!hidden_dentry) { hidden_dentry = create_parents(parent, dentry, bindex); if (!hidden_dentry || IS_ERR(hidden_dentry)) { fist_dprint(8, "hidden dentry NULL for bindex = %d\n", bindex); continue; } } hidden_parent_dentry = lock_parent(hidden_dentry); if (IS_ERR(hidden_parent_dentry)) { err = PTR_ERR(hidden_parent_dentry); goto out; } if (!(err = is_robranch_super(dentry->d_sb, bindex))) { err = vfs_mkdir(hidden_parent_dentry->d_inode, hidden_dentry, mode); } unlock_dir(hidden_parent_dentry); /* XXX this could potentially return a negative hidden_dentry! */ if (err || !hidden_dentry->d_inode) { /* break out of for loop if error returned was NOT -EROFS */ if (!IS_COPYUP_ERR(err)) break; } else { int i; int bend = dbend(dentry); for (i = bindex + 1; i < bend; i++) { if (dtohd_index(dentry, i)) { DPUT(dtohd_index(dentry, i)); set_dtohd_index(dentry, i, NULL); } } bend = bindex; set_dbend(dentry, bend); err = unionfs_interpose(dentry, parent->i_sb, 0); if (!err) { fist_copy_attr_timesizes(parent, hidden_parent_dentry-> d_inode); /* update number of links on parent directory */ parent->i_nlink = get_nlinks(parent); } whiteout_dentry = LOOKUP_ONE_LEN(UNIONFS_DIR_OPAQUE, hidden_dentry, sizeof (UNIONFS_DIR_OPAQUE) - 1); if (IS_ERR(whiteout_dentry)) { err = PTR_ERR(whiteout_dentry); goto out; } down(&hidden_dentry->d_inode->i_sem); err = vfs_create(hidden_dentry->d_inode, whiteout_dentry, 0600, NULL); up(&hidden_dentry->d_inode->i_sem); DPUT(whiteout_dentry); if (err) { fist_dprint(8, "mkdir: error creating directory override entry: %d\n", err); goto out; } break; } } out: if (!dentry->d_inode) d_drop(dentry); KFREE(name); fist_print_dentry("OUT unionfs_mkdir :", dentry); unlock_dentry(dentry); print_exit_status(err); return err; }
static int unionfs_create(struct inode *parent, struct dentry *dentry, int mode, struct nameidata *nd) { int err = 0; struct dentry *hidden_dentry = NULL; struct dentry *whiteout_dentry = NULL; struct dentry *new_hidden_dentry; struct dentry *hidden_parent_dentry = NULL; int bindex = 0, bstart; char *name = NULL; print_entry_location(); lock_dentry(dentry); fist_print_dentry("IN unionfs_create", dentry); /* We start out in the leftmost branch. */ bstart = dbstart(dentry); hidden_dentry = dtohd(dentry); /* check if whiteout exists in this branch, i.e. lookup .wh.foo first */ name = alloc_whname(dentry->d_name.name, dentry->d_name.len); if (IS_ERR(name)) { err = PTR_ERR(name); goto out; } whiteout_dentry = LOOKUP_ONE_LEN(name, hidden_dentry->d_parent, dentry->d_name.len + WHLEN); if (IS_ERR(whiteout_dentry)) { err = PTR_ERR(whiteout_dentry); whiteout_dentry = NULL; goto out; } if (whiteout_dentry->d_inode) { /* .wh.foo has been found. */ /* First truncate it and then rename it to foo (hence having * the same overall effect as a normal create. * * XXX: This is not strictly correct. If we have unlinked the * file and it still has a reference count, then we should * actually unlink the whiteout so that user's data isn't * hosed over. */ struct dentry *hidden_dir_dentry; struct iattr newattrs; down(&whiteout_dentry->d_inode->i_sem); newattrs.ia_valid = ATTR_CTIME | ATTR_MODE | ATTR_ATIME | ATTR_MTIME | ATTR_UID | ATTR_GID | ATTR_FORCE | ATTR_KILL_SUID | ATTR_KILL_SGID; newattrs.ia_mode = mode & ~current->fs->umask; newattrs.ia_uid = current->fsuid; newattrs.ia_gid = current->fsgid; if (whiteout_dentry->d_inode->i_size != 0) { newattrs.ia_valid |= ATTR_SIZE; newattrs.ia_size = 0; } err = notify_change(whiteout_dentry, &newattrs); up(&whiteout_dentry->d_inode->i_sem); if (err) printk(KERN_WARNING "unionfs: %s:%d: notify_change failed: %d, ignoring..\n", __FILE__, __LINE__, err); new_hidden_dentry = dtohd(dentry); DGET(new_hidden_dentry); hidden_dir_dentry = GET_PARENT(whiteout_dentry); lock_rename(hidden_dir_dentry, hidden_dir_dentry); if (!(err = is_robranch_super(dentry->d_sb, bstart))) { err = vfs_rename(hidden_dir_dentry->d_inode, whiteout_dentry, hidden_dir_dentry->d_inode, new_hidden_dentry); } if (!err) { fist_copy_attr_timesizes(parent, new_hidden_dentry->d_parent-> d_inode); parent->i_nlink = get_nlinks(parent); } unlock_rename(hidden_dir_dentry, hidden_dir_dentry); DPUT(hidden_dir_dentry); DPUT(new_hidden_dentry); if (err) { /* exit if the error returned was NOT -EROFS */ if (!IS_COPYUP_ERR(err)) goto out; /* We were not able to create the file in this branch, * so, we try to create it in one branch to left */ bstart--; } else { /* reset the unionfs dentry to point to the .wh.foo entry. */ /* Discard any old reference. */ DPUT(dtohd(dentry)); /* Trade one reference to another. */ set_dtohd_index(dentry, bstart, whiteout_dentry); whiteout_dentry = NULL; err = unionfs_interpose(dentry, parent->i_sb, 0); goto out; } } for (bindex = bstart; bindex >= 0; bindex--) { hidden_dentry = dtohd_index(dentry, bindex); if (!hidden_dentry) { /* if hidden_dentry is NULL, create the entire * dentry directory structure in branch 'bindex'. * hidden_dentry will NOT be null when bindex == bstart * because lookup passed as a negative unionfs dentry * pointing to a lone negative underlying dentry */ hidden_dentry = create_parents(parent, dentry, bindex); if (!hidden_dentry || IS_ERR(hidden_dentry)) { if (IS_ERR(hidden_dentry)) err = PTR_ERR(hidden_dentry); continue; } } fist_checkinode(parent, "unionfs_create"); hidden_parent_dentry = lock_parent(hidden_dentry); if (IS_ERR(hidden_parent_dentry)) { err = PTR_ERR(hidden_parent_dentry); goto out; } /* We shouldn't create things in a read-only branch. */ if (!(err = is_robranch_super(dentry->d_sb, bindex))) { //DQ: vfs_create has a different prototype in 2.6 err = vfs_create(hidden_parent_dentry->d_inode, hidden_dentry, mode, nd); } if (err || !hidden_dentry->d_inode) { unlock_dir(hidden_parent_dentry); /* break out of for loop if the error wasn't -EROFS */ if (!IS_COPYUP_ERR(err)) break; } else { err = unionfs_interpose(dentry, parent->i_sb, 0); if (!err) { fist_copy_attr_timesizes(parent, hidden_parent_dentry-> d_inode); /* update number of links on parent directory */ parent->i_nlink = get_nlinks(parent); } unlock_dir(hidden_parent_dentry); break; } } out: DPUT(whiteout_dentry); KFREE(name); fist_print_dentry("OUT unionfs_create :", dentry); unlock_dentry(dentry); print_exit_status(err); return err; }
static int unionfs_symlink(struct inode *dir, struct dentry *dentry, const char *symname) { int err = 0; struct dentry *hidden_dentry = NULL; struct dentry *whiteout_dentry = NULL; struct dentry *hidden_dir_dentry = NULL; umode_t mode; int bindex = 0, bstart; char *name = NULL; print_entry_location(); lock_dentry(dentry); fist_print_dentry("IN unionfs_symlink", dentry); /* We start out in the leftmost branch. */ bstart = dbstart(dentry); hidden_dentry = dtohd(dentry); /* check if whiteout exists in this branch, i.e. lookup .wh.foo first. If present, delete it */ name = alloc_whname(dentry->d_name.name, dentry->d_name.len); if (IS_ERR(name)) { err = PTR_ERR(name); goto out; } whiteout_dentry = LOOKUP_ONE_LEN(name, hidden_dentry->d_parent, dentry->d_name.len + WHLEN); if (IS_ERR(whiteout_dentry)) { err = PTR_ERR(whiteout_dentry); goto out; } if (!whiteout_dentry->d_inode) { DPUT(whiteout_dentry); whiteout_dentry = NULL; } else { /* found a .wh.foo entry, unlink it and then call vfs_symlink() */ hidden_dir_dentry = lock_parent(whiteout_dentry); fist_print_generic_dentry("HDD", hidden_dir_dentry); fist_print_generic_dentry("WD", whiteout_dentry); if (!(err = is_robranch_super(dentry->d_sb, bstart))) { err = vfs_unlink(hidden_dir_dentry->d_inode, whiteout_dentry); } DPUT(whiteout_dentry); fist_copy_attr_times(dir, hidden_dir_dentry->d_inode); /* propagate number of hard-links */ dir->i_nlink = get_nlinks(dir); unlock_dir(hidden_dir_dentry); if (err) { /* exit if the error returned was NOT -EROFS */ if (!IS_COPYUP_ERR(err)) goto out; /* should now try to create symlink in the another branch */ bstart--; } } /* deleted whiteout if it was present, now do a normal vfs_symlink() with possible recursive directory creation */ for (bindex = bstart; bindex >= 0; bindex--) { hidden_dentry = dtohd_index(dentry, bindex); if (!hidden_dentry) { /* if hidden_dentry is NULL, create the entire * dentry directory structure in branch 'bindex'. hidden_dentry will NOT be null when * bindex == bstart because lookup passed as a negative unionfs dentry pointing to a * lone negative underlying dentry */ hidden_dentry = create_parents(dir, dentry, bindex); if (!hidden_dentry || IS_ERR(hidden_dentry)) { if (IS_ERR(hidden_dentry)) { err = PTR_ERR(hidden_dentry); } fist_dprint(8, "hidden dentry NULL (or error) for bindex = %d\n", bindex); continue; } } hidden_dir_dentry = lock_parent(hidden_dentry); if (!(err = is_robranch_super(dentry->d_sb, bindex))) { mode = S_IALLUGO; err = vfs_symlink(hidden_dir_dentry->d_inode, hidden_dentry, symname, mode); } unlock_dir(hidden_dir_dentry); if (err || !hidden_dentry->d_inode) { /* break out of for loop if error returned was NOT -EROFS */ if (!IS_COPYUP_ERR(err)) break; } else { err = unionfs_interpose(dentry, dir->i_sb, 0); if (!err) { fist_copy_attr_timesizes(dir, hidden_dir_dentry-> d_inode); /* update number of links on parent directory */ dir->i_nlink = get_nlinks(dir); } break; } } out: if (!dentry->d_inode) d_drop(dentry); KFREE(name); fist_print_dentry("OUT unionfs_symlink :", dentry); unlock_dentry(dentry); print_exit_status(err); return err; }
static int unionfs_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry) { int err = 0; struct dentry *hidden_old_dentry = NULL; struct dentry *hidden_new_dentry = NULL; struct dentry *hidden_dir_dentry = NULL; struct dentry *whiteout_dentry; char *name = NULL; print_entry_location(); double_lock_dentry(new_dentry, old_dentry); hidden_new_dentry = dtohd(new_dentry); /* check if whiteout exists in the branch of new dentry, i.e. lookup * .wh.foo first. If present, delete it */ name = alloc_whname(new_dentry->d_name.name, new_dentry->d_name.len); if (IS_ERR(name)) { err = PTR_ERR(name); goto out; } whiteout_dentry = LOOKUP_ONE_LEN(name, hidden_new_dentry->d_parent, new_dentry->d_name.len + WHLEN); if (IS_ERR(whiteout_dentry)) { err = PTR_ERR(whiteout_dentry); goto out; } if (!whiteout_dentry->d_inode) { DPUT(whiteout_dentry); whiteout_dentry = NULL; } else { /* found a .wh.foo entry, unlink it and then call vfs_link() */ hidden_dir_dentry = lock_parent(whiteout_dentry); if (! (err = is_robranch_super(new_dentry->d_sb, dbstart(new_dentry)))) { err = vfs_unlink(hidden_dir_dentry->d_inode, whiteout_dentry); } fist_copy_attr_times(dir, hidden_dir_dentry->d_inode); dir->i_nlink = get_nlinks(dir); unlock_dir(hidden_dir_dentry); hidden_dir_dentry = NULL; DPUT(whiteout_dentry); if (err) goto out; } if (dbstart(old_dentry) != dbstart(new_dentry)) { hidden_new_dentry = create_parents(dir, new_dentry, dbstart(old_dentry)); err = PTR_ERR(hidden_new_dentry); if (IS_COPYUP_ERR(err)) goto docopyup; if (!hidden_new_dentry || IS_ERR(hidden_new_dentry)) goto out; } hidden_new_dentry = dtohd(new_dentry); hidden_old_dentry = dtohd(old_dentry); BUG_ON(dbstart(old_dentry) != dbstart(new_dentry)); hidden_dir_dentry = lock_parent(hidden_new_dentry); if (!(err = is_robranch(old_dentry))) err = vfs_link(hidden_old_dentry, hidden_dir_dentry->d_inode, hidden_new_dentry); unlock_dir(hidden_dir_dentry); docopyup: if (IS_COPYUP_ERR(err)) { int old_bstart = dbstart(old_dentry); int bindex; for (bindex = old_bstart - 1; bindex >= 0; bindex--) { err = copyup_dentry(old_dentry->d_parent-> d_inode, old_dentry, old_bstart, bindex, NULL, old_dentry->d_inode->i_size); if (!err) { hidden_new_dentry = create_parents(dir, new_dentry, bindex); hidden_old_dentry = dtohd(old_dentry); hidden_dir_dentry = lock_parent(hidden_new_dentry); /* do vfs_link */ err = vfs_link(hidden_old_dentry, hidden_dir_dentry->d_inode, hidden_new_dentry); unlock_dir(hidden_dir_dentry); goto check_link; } } goto out; } check_link: if (err || !hidden_new_dentry->d_inode) goto out; /* Its a hard link, so use the same inode */ new_dentry->d_inode = IGRAB(old_dentry->d_inode); d_instantiate(new_dentry, new_dentry->d_inode); fist_copy_attr_all(dir, hidden_new_dentry->d_parent->d_inode); /* propagate number of hard-links */ old_dentry->d_inode->i_nlink = get_nlinks(old_dentry->d_inode); out: if (!new_dentry->d_inode) d_drop(new_dentry); KFREE(name); unlock_dentry(new_dentry); unlock_dentry(old_dentry); print_exit_status(err); return err; }