From 0e5b044cbf3a41b4efad7d9616342338f88b373d Mon Sep 17 00:00:00 2001 From: Konstantin Komarov Date: Wed, 13 Jul 2022 18:00:03 +0300 Subject: fs/ntfs3: Refactoring attr_set_size to restore after errors Added comments to code Added two undo labels for restoring after errors Signed-off-by: Konstantin Komarov --- fs/ntfs3/attrib.c | 180 ++++++++++++++++++++++++++++++++++++++---------------- 1 file changed, 126 insertions(+), 54 deletions(-) (limited to 'fs/ntfs3/attrib.c') diff --git a/fs/ntfs3/attrib.c b/fs/ntfs3/attrib.c index 5ba83eb0fc07..c29b2debc909 100644 --- a/fs/ntfs3/attrib.c +++ b/fs/ntfs3/attrib.c @@ -173,7 +173,6 @@ int attr_allocate_clusters(struct ntfs_sb_info *sbi, struct runs_tree *run, { int err; CLST flen, vcn0 = vcn, pre = pre_alloc ? *pre_alloc : 0; - struct wnd_bitmap *wnd = &sbi->used.bitmap; size_t cnt = run->count; for (;;) { @@ -196,9 +195,7 @@ int attr_allocate_clusters(struct ntfs_sb_info *sbi, struct runs_tree *run, /* Add new fragment into run storage. */ if (!run_add_entry(run, vcn, lcn, flen, opt == ALLOCATE_MFT)) { /* Undo last 'ntfs_look_for_free_space' */ - down_write_nested(&wnd->rw_lock, BITMAP_MUTEX_CLUSTERS); - wnd_set_free(wnd, lcn, flen); - up_write(&wnd->rw_lock); + mark_as_free_ex(sbi, lcn, len, false); err = -ENOMEM; goto out; } @@ -419,40 +416,44 @@ int attr_set_size(struct ntfs_inode *ni, enum ATTR_TYPE type, struct mft_inode *mi, *mi_b; CLST alen, vcn, lcn, new_alen, old_alen, svcn, evcn; CLST next_svcn, pre_alloc = -1, done = 0; - bool is_ext; + bool is_ext, is_bad = false; u32 align; struct MFT_REC *rec; again: + alen = 0; le_b = NULL; attr_b = ni_find_attr(ni, NULL, &le_b, type, name, name_len, NULL, &mi_b); if (!attr_b) { err = -ENOENT; - goto out; + goto bad_inode; } if (!attr_b->non_res) { err = attr_set_size_res(ni, attr_b, le_b, mi_b, new_size, run, &attr_b); - if (err || !attr_b->non_res) - goto out; + if (err) + return err; + + /* Return if file is still resident. */ + if (!attr_b->non_res) + goto ok1; /* Layout of records may be changed, so do a full search. */ goto again; } is_ext = is_attr_ext(attr_b); - -again_1: align = sbi->cluster_size; - if (is_ext) align <<= attr_b->nres.c_unit; old_valid = le64_to_cpu(attr_b->nres.valid_size); old_size = le64_to_cpu(attr_b->nres.data_size); old_alloc = le64_to_cpu(attr_b->nres.alloc_size); + +again_1: old_alen = old_alloc >> cluster_bits; new_alloc = (new_size + align - 1) & ~(u64)(align - 1); @@ -475,24 +476,27 @@ again_1: mi = mi_b; } else if (!le_b) { err = -EINVAL; - goto out; + goto bad_inode; } else { le = le_b; attr = ni_find_attr(ni, attr_b, &le, type, name, name_len, &vcn, &mi); if (!attr) { err = -EINVAL; - goto out; + goto bad_inode; } next_le_1: svcn = le64_to_cpu(attr->nres.svcn); evcn = le64_to_cpu(attr->nres.evcn); } - + /* + * Here we have: + * attr,mi,le - last attribute segment (containing 'vcn'). + * attr_b,mi_b,le_b - base (primary) attribute segment. + */ next_le: rec = mi->mrec; - err = attr_load_runs(attr, ni, run, NULL); if (err) goto out; @@ -507,6 +511,13 @@ next_le: goto ok; } + /* + * Add clusters. In simple case we have to: + * - allocate space (vcn, lcn, len) + * - update packed run in 'mi' + * - update attr->nres.evcn + * - update attr_b->nres.data_size/attr_b->nres.alloc_size + */ to_allocate = new_alen - old_alen; add_alloc_in_same_attr_seg: lcn = 0; @@ -520,9 +531,11 @@ add_alloc_in_same_attr_seg: pre_alloc = 0; if (type == ATTR_DATA && !name_len && sbi->options->prealloc) { - CLST new_alen2 = bytes_to_cluster( - sbi, get_pre_allocated(new_size)); - pre_alloc = new_alen2 - new_alen; + pre_alloc = + bytes_to_cluster( + sbi, + get_pre_allocated(new_size)) - + new_alen; } /* Get the last LCN to allocate from. */ @@ -580,7 +593,7 @@ add_alloc_in_same_attr_seg: pack_runs: err = mi_pack_runs(mi, attr, run, vcn - svcn); if (err) - goto out; + goto undo_1; next_svcn = le64_to_cpu(attr->nres.evcn) + 1; new_alloc_tmp = (u64)next_svcn << cluster_bits; @@ -614,7 +627,7 @@ pack_runs: if (type == ATTR_LIST) { err = ni_expand_list(ni); if (err) - goto out; + goto undo_2; if (next_svcn < vcn) goto pack_runs; @@ -624,8 +637,9 @@ pack_runs: if (!ni->attr_list.size) { err = ni_create_attr_list(ni); + /* In case of error layout of records is not changed. */ if (err) - goto out; + goto undo_2; /* Layout of records is changed. */ } @@ -638,47 +652,56 @@ pack_runs: err = ni_insert_nonresident(ni, type, name, name_len, run, next_svcn, vcn - next_svcn, attr_b->flags, &attr, &mi, NULL); - if (err) - goto out; - - if (!is_mft) - run_truncate_head(run, evcn + 1); - svcn = le64_to_cpu(attr->nres.svcn); - evcn = le64_to_cpu(attr->nres.evcn); - - le_b = NULL; /* * Layout of records maybe changed. * Find base attribute to update. */ + le_b = NULL; attr_b = ni_find_attr(ni, NULL, &le_b, type, name, name_len, NULL, &mi_b); if (!attr_b) { - err = -ENOENT; - goto out; + err = -EINVAL; + goto bad_inode; } - attr_b->nres.alloc_size = cpu_to_le64((u64)vcn << cluster_bits); - attr_b->nres.data_size = attr_b->nres.alloc_size; - attr_b->nres.valid_size = attr_b->nres.alloc_size; + if (err) { + /* ni_insert_nonresident failed. */ + attr = NULL; + goto undo_2; + } + + if (!is_mft) + run_truncate_head(run, evcn + 1); + + svcn = le64_to_cpu(attr->nres.svcn); + evcn = le64_to_cpu(attr->nres.evcn); + + /* + * Attribute is in consistency state. + * Save this point to restore to if next steps fail. + */ + old_valid = old_size = old_alloc = (u64)vcn << cluster_bits; + attr_b->nres.valid_size = attr_b->nres.data_size = + attr_b->nres.alloc_size = cpu_to_le64(old_size); mi_b->dirty = true; goto again_1; } if (new_size != old_size || (new_alloc != old_alloc && !keep_prealloc)) { + /* + * Truncate clusters. In simple case we have to: + * - update packed run in 'mi' + * - update attr->nres.evcn + * - update attr_b->nres.data_size/attr_b->nres.alloc_size + * - mark and trim clusters as free (vcn, lcn, len) + */ + CLST dlen = 0; + vcn = max(svcn, new_alen); new_alloc_tmp = (u64)vcn << cluster_bits; - alen = 0; - err = run_deallocate_ex(sbi, run, vcn, evcn - vcn + 1, &alen, - true); - if (err) - goto out; - - run_truncate(run, vcn); - if (vcn > svcn) { err = mi_pack_runs(mi, attr, run, vcn - svcn); if (err) @@ -697,7 +720,7 @@ pack_runs: if (!al_remove_le(ni, le)) { err = -EINVAL; - goto out; + goto bad_inode; } le = (struct ATTR_LIST_ENTRY *)((u8 *)le - le_sz); @@ -723,12 +746,20 @@ pack_runs: attr_b->nres.valid_size = attr_b->nres.alloc_size; } + mi_b->dirty = true; - if (is_ext) + err = run_deallocate_ex(sbi, run, vcn, evcn - vcn + 1, &dlen, + true); + if (err) + goto out; + + if (is_ext) { + /* dlen - really deallocated clusters. */ le64_sub_cpu(&attr_b->nres.total_size, - ((u64)alen << cluster_bits)); + ((u64)dlen << cluster_bits)); + } - mi_b->dirty = true; + run_truncate(run, vcn); if (new_alloc_tmp <= new_alloc) goto ok; @@ -747,7 +778,7 @@ pack_runs: if (le->type != type || le->name_len != name_len || memcmp(le_name(le), name, name_len * sizeof(short))) { err = -EINVAL; - goto out; + goto bad_inode; } err = ni_load_mi(ni, le, &mi); @@ -757,7 +788,7 @@ pack_runs: attr = mi_find_attr(mi, NULL, type, name, name_len, &le->id); if (!attr) { err = -EINVAL; - goto out; + goto bad_inode; } goto next_le_1; } @@ -772,13 +803,13 @@ ok: } } -out: - if (!err && attr_b && ret) +ok1: + if (ret) *ret = attr_b; /* Update inode_set_bytes. */ - if (!err && ((type == ATTR_DATA && !name_len) || - (type == ATTR_ALLOC && name == I30_NAME))) { + if (((type == ATTR_DATA && !name_len) || + (type == ATTR_ALLOC && name == I30_NAME))) { bool dirty = false; if (ni->vfs_inode.i_size != new_size) { @@ -786,7 +817,7 @@ out: dirty = true; } - if (attr_b && attr_b->non_res) { + if (attr_b->non_res) { new_alloc = le64_to_cpu(attr_b->nres.alloc_size); if (inode_get_bytes(&ni->vfs_inode) != new_alloc) { inode_set_bytes(&ni->vfs_inode, new_alloc); @@ -800,6 +831,47 @@ out: } } + return 0; + +undo_2: + vcn -= alen; + attr_b->nres.data_size = cpu_to_le64(old_size); + attr_b->nres.valid_size = cpu_to_le64(old_valid); + attr_b->nres.alloc_size = cpu_to_le64(old_alloc); + + /* Restore 'attr' and 'mi'. */ + if (attr) + goto restore_run; + + if (le64_to_cpu(attr_b->nres.svcn) <= svcn && + svcn <= le64_to_cpu(attr_b->nres.evcn)) { + attr = attr_b; + le = le_b; + mi = mi_b; + } else if (!le_b) { + err = -EINVAL; + goto bad_inode; + } else { + le = le_b; + attr = ni_find_attr(ni, attr_b, &le, type, name, name_len, + &svcn, &mi); + if (!attr) + goto bad_inode; + } + +restore_run: + if (mi_pack_runs(mi, attr, run, evcn - svcn + 1)) + is_bad = true; + +undo_1: + run_deallocate_ex(sbi, run, vcn, alen, NULL, false); + + run_truncate(run, vcn); +out: + if (is_bad) { +bad_inode: + _ntfs_bad_inode(&ni->vfs_inode); + } return err; } -- cgit v1.2.3