From 20abc64f78346ac591344133301661b77e1c8253 Mon Sep 17 00:00:00 2001 From: Konstantin Komarov Date: Wed, 13 Jul 2022 18:18:48 +0300 Subject: fs/ntfs3: Refactoring attr_punch_hole to restore after errors Added comments to code Added new function run_clone to make a copy of run Added done and undo labels for restoring after errors Signed-off-by: Konstantin Komarov --- fs/ntfs3/attrib.c | 117 ++++++++++++++++++++++++++++++++++++------------------ 1 file changed, 79 insertions(+), 38 deletions(-) (limited to 'fs/ntfs3/attrib.c') diff --git a/fs/ntfs3/attrib.c b/fs/ntfs3/attrib.c index c29b2debc909..cf3729ce771b 100644 --- a/fs/ntfs3/attrib.c +++ b/fs/ntfs3/attrib.c @@ -140,7 +140,10 @@ failed: } if (lcn != SPARSE_LCN) { - mark_as_free_ex(sbi, lcn, clen, trim); + if (sbi) { + /* mark bitmap range [lcn + clen) as free and trim clusters. */ + mark_as_free_ex(sbi, lcn, clen, trim); + } dn += clen; } @@ -2002,10 +2005,11 @@ int attr_punch_hole(struct ntfs_inode *ni, u64 vbo, u64 bytes, u32 *frame_size) struct ATTRIB *attr = NULL, *attr_b; struct ATTR_LIST_ENTRY *le, *le_b; struct mft_inode *mi, *mi_b; - CLST svcn, evcn1, vcn, len, end, alen, dealloc, next_svcn; + CLST svcn, evcn1, vcn, len, end, alen, hole, next_svcn; u64 total_size, alloc_size; u32 mask; __le16 a_flags; + struct runs_tree run2; if (!bytes) return 0; @@ -2057,6 +2061,9 @@ int attr_punch_hole(struct ntfs_inode *ni, u64 vbo, u64 bytes, u32 *frame_size) } down_write(&ni->file.run_lock); + run_init(&run2); + run_truncate(run, 0); + /* * Enumerate all attribute segments and punch hole where necessary. */ @@ -2064,7 +2071,7 @@ int attr_punch_hole(struct ntfs_inode *ni, u64 vbo, u64 bytes, u32 *frame_size) vcn = vbo >> sbi->cluster_bits; len = bytes >> sbi->cluster_bits; end = vcn + len; - dealloc = 0; + hole = 0; svcn = le64_to_cpu(attr_b->nres.svcn); evcn1 = le64_to_cpu(attr_b->nres.evcn) + 1; @@ -2076,14 +2083,14 @@ int attr_punch_hole(struct ntfs_inode *ni, u64 vbo, u64 bytes, u32 *frame_size) 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, ATTR_DATA, NULL, 0, &vcn, &mi); if (!attr) { err = -EINVAL; - goto out; + goto bad_inode; } svcn = le64_to_cpu(attr->nres.svcn); @@ -2091,69 +2098,91 @@ int attr_punch_hole(struct ntfs_inode *ni, u64 vbo, u64 bytes, u32 *frame_size) } while (svcn < end) { - CLST vcn1, zero, dealloc2; + CLST vcn1, zero, hole2 = hole; err = attr_load_runs(attr, ni, run, &svcn); if (err) - goto out; + goto done; vcn1 = max(vcn, svcn); zero = min(end, evcn1) - vcn1; - dealloc2 = dealloc; - err = run_deallocate_ex(sbi, run, vcn1, zero, &dealloc, true); + /* + * Check range [vcn1 + zero). + * Calculate how many clusters there are. + * Don't do any destructive actions. + */ + err = run_deallocate_ex(NULL, run, vcn1, zero, &hole2, false); if (err) - goto out; + goto done; - if (dealloc2 == dealloc) { - /* Looks like the required range is already sparsed. */ - } else { - if (!run_add_entry(run, vcn1, SPARSE_LCN, zero, - false)) { - err = -ENOMEM; - goto out; - } + /* Check if required range is already hole. */ + if (hole2 == hole) + goto next_attr; - err = mi_pack_runs(mi, attr, run, evcn1 - svcn); + /* Make a clone of run to undo. */ + err = run_clone(run, &run2); + if (err) + goto done; + + /* Make a hole range (sparse) [vcn1 + zero). */ + if (!run_add_entry(run, vcn1, SPARSE_LCN, zero, false)) { + err = -ENOMEM; + goto done; + } + + /* Update run in attribute segment. */ + err = mi_pack_runs(mi, attr, run, evcn1 - svcn); + if (err) + goto done; + next_svcn = le64_to_cpu(attr->nres.evcn) + 1; + if (next_svcn < evcn1) { + /* Insert new attribute segment. */ + err = ni_insert_nonresident(ni, ATTR_DATA, NULL, 0, run, + next_svcn, + evcn1 - next_svcn, a_flags, + &attr, &mi, &le); if (err) - goto out; - next_svcn = le64_to_cpu(attr->nres.evcn) + 1; - if (next_svcn < evcn1) { - err = ni_insert_nonresident(ni, ATTR_DATA, NULL, - 0, run, next_svcn, - evcn1 - next_svcn, - a_flags, &attr, &mi, - &le); - if (err) - goto out; - /* Layout of records maybe changed. */ - attr_b = NULL; - } + goto undo_punch; + + /* Layout of records maybe changed. */ + attr_b = NULL; } + + /* Real deallocate. Should not fail. */ + run_deallocate_ex(sbi, &run2, vcn1, zero, &hole, true); + +next_attr: /* Free all allocated memory. */ run_truncate(run, 0); if (evcn1 >= alen) break; + /* Get next attribute segment. */ attr = ni_enum_attr_ex(ni, attr, &le, &mi); if (!attr) { err = -EINVAL; - goto out; + goto bad_inode; } svcn = le64_to_cpu(attr->nres.svcn); evcn1 = le64_to_cpu(attr->nres.evcn) + 1; } - total_size -= (u64)dealloc << sbi->cluster_bits; +done: + if (!hole) + goto out; + if (!attr_b) { attr_b = ni_find_attr(ni, NULL, NULL, ATTR_DATA, NULL, 0, NULL, &mi_b); if (!attr_b) { err = -EINVAL; - goto out; + goto bad_inode; } } + + total_size -= (u64)hole << sbi->cluster_bits; attr_b->nres.total_size = cpu_to_le64(total_size); mi_b->dirty = true; @@ -2163,11 +2192,23 @@ int attr_punch_hole(struct ntfs_inode *ni, u64 vbo, u64 bytes, u32 *frame_size) mark_inode_dirty(&ni->vfs_inode); out: + run_close(&run2); up_write(&ni->file.run_lock); - if (err) - _ntfs_bad_inode(&ni->vfs_inode); - return err; + +bad_inode: + _ntfs_bad_inode(&ni->vfs_inode); + goto out; + +undo_punch: + /* + * Restore packed runs. + * 'mi_pack_runs' should not fail, cause we restore original. + */ + if (mi_pack_runs(mi, attr, &run2, evcn1 - svcn)) + goto bad_inode; + + goto done; } /* -- cgit v1.2.3