diff options
Diffstat (limited to 'kernel/fs/btrfs/send.c')
| -rw-r--r-- | kernel/fs/btrfs/send.c | 377 |
1 files changed, 320 insertions, 57 deletions
diff --git a/kernel/fs/btrfs/send.c b/kernel/fs/btrfs/send.c index a1216f9b4..63a6152be 100644 --- a/kernel/fs/btrfs/send.c +++ b/kernel/fs/btrfs/send.c @@ -243,6 +243,7 @@ struct waiting_dir_move { * after this directory is moved, we can try to rmdir the ino rmdir_ino. */ u64 rmdir_ino; + bool orphanized; }; struct orphan_dir_info { @@ -1158,6 +1159,9 @@ struct backref_ctx { /* may be truncated in case it's the last extent in a file */ u64 extent_len; + /* data offset in the file extent item */ + u64 data_offset; + /* Just to check for bugs in backref resolving */ int found_itself; }; @@ -1221,7 +1225,7 @@ static int __iterate_backrefs(u64 ino, u64 offset, u64 root, void *ctx_) if (ret < 0) return ret; - if (offset + bctx->extent_len > i_size) + if (offset + bctx->data_offset + bctx->extent_len > i_size) return 0; /* @@ -1363,6 +1367,19 @@ static int find_extent_clone(struct send_ctx *sctx, backref_ctx->cur_offset = data_offset; backref_ctx->found_itself = 0; backref_ctx->extent_len = num_bytes; + /* + * For non-compressed extents iterate_extent_inodes() gives us extent + * offsets that already take into account the data offset, but not for + * compressed extents, since the offset is logical and not relative to + * the physical extent locations. We must take this into account to + * avoid sending clone offsets that go beyond the source file's size, + * which would result in the clone ioctl failing with -EINVAL on the + * receiving end. + */ + if (compressed == BTRFS_COMPRESS_NONE) + backref_ctx->data_offset = 0; + else + backref_ctx->data_offset = btrfs_file_extent_offset(eb, fi); /* * The last extent of a file may be too large due to page alignment. @@ -1417,16 +1434,6 @@ verbose_printk(KERN_DEBUG "btrfs: find_extent_clone: data_offset=%llu, " } if (cur_clone_root) { - if (compressed != BTRFS_COMPRESS_NONE) { - /* - * Offsets given by iterate_extent_inodes() are relative - * to the start of the extent, we need to add logical - * offset from the file extent item. - * (See why at backref.c:check_extent_in_eb()) - */ - cur_clone_root->offset += btrfs_file_extent_offset(eb, - fi); - } *found = cur_clone_root; ret = 0; } else { @@ -1462,7 +1469,21 @@ static int read_symlink(struct btrfs_root *root, ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); if (ret < 0) goto out; - BUG_ON(ret); + if (ret) { + /* + * An empty symlink inode. Can happen in rare error paths when + * creating a symlink (transaction committed before the inode + * eviction handler removed the symlink inode items and a crash + * happened in between or the subvol was snapshoted in between). + * Print an informative message to dmesg/syslog so that the user + * can delete the symlink. + */ + btrfs_err(root->fs_info, + "Found empty symlink inode %llu at root %llu", + ino, root->root_key.objectid); + ret = -EIO; + goto out; + } ei = btrfs_item_ptr(path->nodes[0], path->slots[0], struct btrfs_file_extent_item); @@ -1900,8 +1921,15 @@ static int did_overwrite_ref(struct send_ctx *sctx, goto out; } - /* we know that it is or will be overwritten. check this now */ - if (ow_inode < sctx->send_progress) + /* + * We know that it is or will be overwritten. Check this now. + * The current inode being processed might have been the one that caused + * inode 'ino' to be orphanized, therefore check if ow_inode matches + * the current inode being processed. + */ + if ((ow_inode < sctx->send_progress) || + (ino != sctx->cur_ino && ow_inode == sctx->cur_ino && + gen == sctx->cur_inode_gen)) ret = 1; else ret = 0; @@ -2223,6 +2251,8 @@ static int get_cur_path(struct send_ctx *sctx, u64 ino, u64 gen, fs_path_reset(dest); while (!stop && ino != BTRFS_FIRST_FREE_OBJECTID) { + struct waiting_dir_move *wdm; + fs_path_reset(name); if (is_waiting_for_rm(sctx, ino)) { @@ -2233,7 +2263,11 @@ static int get_cur_path(struct send_ctx *sctx, u64 ino, u64 gen, break; } - if (is_waiting_for_move(sctx, ino)) { + wdm = get_waiting_dir_move(sctx, ino); + if (wdm && wdm->orphanized) { + ret = gen_unique_name(sctx, ino, gen, name); + stop = 1; + } else if (wdm) { ret = get_first_ref(sctx->parent_root, ino, &parent_inode, &parent_gen, name); } else { @@ -2323,13 +2357,23 @@ static int send_subvol_begin(struct send_ctx *sctx) } TLV_PUT_STRING(sctx, BTRFS_SEND_A_PATH, name, namelen); - TLV_PUT_UUID(sctx, BTRFS_SEND_A_UUID, - sctx->send_root->root_item.uuid); + + if (!btrfs_is_empty_uuid(sctx->send_root->root_item.received_uuid)) + TLV_PUT_UUID(sctx, BTRFS_SEND_A_UUID, + sctx->send_root->root_item.received_uuid); + else + TLV_PUT_UUID(sctx, BTRFS_SEND_A_UUID, + sctx->send_root->root_item.uuid); + TLV_PUT_U64(sctx, BTRFS_SEND_A_CTRANSID, le64_to_cpu(sctx->send_root->root_item.ctransid)); if (parent_root) { - TLV_PUT_UUID(sctx, BTRFS_SEND_A_CLONE_UUID, - sctx->parent_root->root_item.uuid); + if (!btrfs_is_empty_uuid(parent_root->root_item.received_uuid)) + TLV_PUT_UUID(sctx, BTRFS_SEND_A_CLONE_UUID, + parent_root->root_item.received_uuid); + else + TLV_PUT_UUID(sctx, BTRFS_SEND_A_CLONE_UUID, + parent_root->root_item.uuid); TLV_PUT_U64(sctx, BTRFS_SEND_A_CLONE_CTRANSID, le64_to_cpu(sctx->parent_root->root_item.ctransid)); } @@ -2530,7 +2574,7 @@ verbose_printk("btrfs: send_create_inode %llu\n", ino); } else if (S_ISSOCK(mode)) { cmd = BTRFS_SEND_C_MKSOCK; } else { - printk(KERN_WARNING "btrfs: unexpected inode type %o", + btrfs_warn(sctx->send_root->fs_info, "unexpected inode type %o", (int)(mode & S_IFMT)); ret = -ENOTSUPP; goto out; @@ -2923,7 +2967,7 @@ static int is_waiting_for_move(struct send_ctx *sctx, u64 ino) return entry != NULL; } -static int add_waiting_dir_move(struct send_ctx *sctx, u64 ino) +static int add_waiting_dir_move(struct send_ctx *sctx, u64 ino, bool orphanized) { struct rb_node **p = &sctx->waiting_dir_moves.rb_node; struct rb_node *parent = NULL; @@ -2934,6 +2978,7 @@ static int add_waiting_dir_move(struct send_ctx *sctx, u64 ino) return -ENOMEM; dm->ino = ino; dm->rmdir_ino = 0; + dm->orphanized = orphanized; while (*p) { parent = *p; @@ -3030,7 +3075,7 @@ static int add_pending_dir_move(struct send_ctx *sctx, goto out; } - ret = add_waiting_dir_move(sctx, pm->ino); + ret = add_waiting_dir_move(sctx, pm->ino, is_orphan); if (ret) goto out; @@ -3353,8 +3398,40 @@ out: return ret; } +/* + * Check if ino ino1 is an ancestor of inode ino2 in the given root. + * Return 1 if true, 0 if false and < 0 on error. + */ +static int is_ancestor(struct btrfs_root *root, + const u64 ino1, + const u64 ino1_gen, + const u64 ino2, + struct fs_path *fs_path) +{ + u64 ino = ino2; + + while (ino > BTRFS_FIRST_FREE_OBJECTID) { + int ret; + u64 parent; + u64 parent_gen; + + fs_path_reset(fs_path); + ret = get_first_ref(root, ino, &parent, &parent_gen, fs_path); + if (ret < 0) { + if (ret == -ENOENT && ino == ino2) + ret = 0; + return ret; + } + if (parent == ino1) + return parent_gen == ino1_gen ? 1 : 0; + ino = parent; + } + return 0; +} + static int wait_for_parent_move(struct send_ctx *sctx, - struct recorded_ref *parent_ref) + struct recorded_ref *parent_ref, + const bool is_orphan) { int ret = 0; u64 ino = parent_ref->dir; @@ -3374,11 +3451,24 @@ static int wait_for_parent_move(struct send_ctx *sctx, * Our current directory inode may not yet be renamed/moved because some * ancestor (immediate or not) has to be renamed/moved first. So find if * such ancestor exists and make sure our own rename/move happens after - * that ancestor is processed. + * that ancestor is processed to avoid path build infinite loops (done + * at get_cur_path()). */ while (ino > BTRFS_FIRST_FREE_OBJECTID) { if (is_waiting_for_move(sctx, ino)) { - ret = 1; + /* + * If the current inode is an ancestor of ino in the + * parent root, we need to delay the rename of the + * current inode, otherwise don't delayed the rename + * because we can end up with a circular dependency + * of renames, resulting in some directories never + * getting the respective rename operations issued in + * the send stream or getting into infinite path build + * loops. + */ + ret = is_ancestor(sctx->parent_root, + sctx->cur_ino, sctx->cur_inode_gen, + ino, path_before); break; } @@ -3420,7 +3510,7 @@ out: ino, &sctx->new_refs, &sctx->deleted_refs, - false); + is_orphan); if (!ret) ret = 1; } @@ -3589,6 +3679,17 @@ verbose_printk("btrfs: process_recorded_refs %llu\n", sctx->cur_ino); } } + if (S_ISDIR(sctx->cur_inode_mode) && sctx->parent_root && + can_rename) { + ret = wait_for_parent_move(sctx, cur, is_orphan); + if (ret < 0) + goto out; + if (ret == 1) { + can_rename = false; + *pending_move = 1; + } + } + /* * link/move the ref to the new place. If we have an orphan * inode, move it and update valid_path. If not, link or move @@ -3609,18 +3710,11 @@ verbose_printk("btrfs: process_recorded_refs %llu\n", sctx->cur_ino); * dirs, we always have one new and one deleted * ref. The deleted ref is ignored later. */ - ret = wait_for_parent_move(sctx, cur); - if (ret < 0) - goto out; - if (ret) { - *pending_move = 1; - } else { - ret = send_rename(sctx, valid_path, - cur->full_path); - if (!ret) - ret = fs_path_copy(valid_path, - cur->full_path); - } + ret = send_rename(sctx, valid_path, + cur->full_path); + if (!ret) + ret = fs_path_copy(valid_path, + cur->full_path); if (ret < 0) goto out; } else { @@ -4508,8 +4602,21 @@ verbose_printk("btrfs: send_clone offset=%llu, len=%d, clone_root=%llu, " if (ret < 0) goto out; - TLV_PUT_UUID(sctx, BTRFS_SEND_A_CLONE_UUID, - clone_root->root->root_item.uuid); + /* + * If the parent we're using has a received_uuid set then use that as + * our clone source as that is what we will look for when doing a + * receive. + * + * This covers the case that we create a snapshot off of a received + * subvolume and then use that as the parent and try to receive on a + * different host. + */ + if (!btrfs_is_empty_uuid(clone_root->root->root_item.received_uuid)) + TLV_PUT_UUID(sctx, BTRFS_SEND_A_CLONE_UUID, + clone_root->root->root_item.received_uuid); + else + TLV_PUT_UUID(sctx, BTRFS_SEND_A_CLONE_UUID, + clone_root->root->root_item.uuid); TLV_PUT_U64(sctx, BTRFS_SEND_A_CLONE_CTRANSID, le64_to_cpu(clone_root->root->root_item.ctransid)); TLV_PUT_PATH(sctx, BTRFS_SEND_A_CLONE_PATH, p); @@ -4590,6 +4697,171 @@ tlv_put_failure: return ret; } +static int send_extent_data(struct send_ctx *sctx, + const u64 offset, + const u64 len) +{ + u64 sent = 0; + + if (sctx->flags & BTRFS_SEND_FLAG_NO_FILE_DATA) + return send_update_extent(sctx, offset, len); + + while (sent < len) { + u64 size = len - sent; + int ret; + + if (size > BTRFS_SEND_READ_SIZE) + size = BTRFS_SEND_READ_SIZE; + ret = send_write(sctx, offset + sent, size); + if (ret < 0) + return ret; + if (!ret) + break; + sent += ret; + } + return 0; +} + +static int clone_range(struct send_ctx *sctx, + struct clone_root *clone_root, + const u64 disk_byte, + u64 data_offset, + u64 offset, + u64 len) +{ + struct btrfs_path *path; + struct btrfs_key key; + int ret; + + path = alloc_path_for_send(); + if (!path) + return -ENOMEM; + + /* + * We can't send a clone operation for the entire range if we find + * extent items in the respective range in the source file that + * refer to different extents or if we find holes. + * So check for that and do a mix of clone and regular write/copy + * operations if needed. + * + * Example: + * + * mkfs.btrfs -f /dev/sda + * mount /dev/sda /mnt + * xfs_io -f -c "pwrite -S 0xaa 0K 100K" /mnt/foo + * cp --reflink=always /mnt/foo /mnt/bar + * xfs_io -c "pwrite -S 0xbb 50K 50K" /mnt/foo + * btrfs subvolume snapshot -r /mnt /mnt/snap + * + * If when we send the snapshot and we are processing file bar (which + * has a higher inode number than foo) we blindly send a clone operation + * for the [0, 100K[ range from foo to bar, the receiver ends up getting + * a file bar that matches the content of file foo - iow, doesn't match + * the content from bar in the original filesystem. + */ + key.objectid = clone_root->ino; + key.type = BTRFS_EXTENT_DATA_KEY; + key.offset = clone_root->offset; + ret = btrfs_search_slot(NULL, clone_root->root, &key, path, 0, 0); + if (ret < 0) + goto out; + if (ret > 0 && path->slots[0] > 0) { + btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0] - 1); + if (key.objectid == clone_root->ino && + key.type == BTRFS_EXTENT_DATA_KEY) + path->slots[0]--; + } + + while (true) { + struct extent_buffer *leaf = path->nodes[0]; + int slot = path->slots[0]; + struct btrfs_file_extent_item *ei; + u8 type; + u64 ext_len; + u64 clone_len; + + if (slot >= btrfs_header_nritems(leaf)) { + ret = btrfs_next_leaf(clone_root->root, path); + if (ret < 0) + goto out; + else if (ret > 0) + break; + continue; + } + + btrfs_item_key_to_cpu(leaf, &key, slot); + + /* + * We might have an implicit trailing hole (NO_HOLES feature + * enabled). We deal with it after leaving this loop. + */ + if (key.objectid != clone_root->ino || + key.type != BTRFS_EXTENT_DATA_KEY) + break; + + ei = btrfs_item_ptr(leaf, slot, struct btrfs_file_extent_item); + type = btrfs_file_extent_type(leaf, ei); + if (type == BTRFS_FILE_EXTENT_INLINE) { + ext_len = btrfs_file_extent_inline_len(leaf, slot, ei); + ext_len = PAGE_CACHE_ALIGN(ext_len); + } else { + ext_len = btrfs_file_extent_num_bytes(leaf, ei); + } + + if (key.offset + ext_len <= clone_root->offset) + goto next; + + if (key.offset > clone_root->offset) { + /* Implicit hole, NO_HOLES feature enabled. */ + u64 hole_len = key.offset - clone_root->offset; + + if (hole_len > len) + hole_len = len; + ret = send_extent_data(sctx, offset, hole_len); + if (ret < 0) + goto out; + + len -= hole_len; + if (len == 0) + break; + offset += hole_len; + clone_root->offset += hole_len; + data_offset += hole_len; + } + + if (key.offset >= clone_root->offset + len) + break; + + clone_len = min_t(u64, ext_len, len); + + if (btrfs_file_extent_disk_bytenr(leaf, ei) == disk_byte && + btrfs_file_extent_offset(leaf, ei) == data_offset) + ret = send_clone(sctx, offset, clone_len, clone_root); + else + ret = send_extent_data(sctx, offset, clone_len); + + if (ret < 0) + goto out; + + len -= clone_len; + if (len == 0) + break; + offset += clone_len; + clone_root->offset += clone_len; + data_offset += clone_len; +next: + path->slots[0]++; + } + + if (len > 0) + ret = send_extent_data(sctx, offset, len); + else + ret = 0; +out: + btrfs_free_path(path); + return ret; +} + static int send_write_or_clone(struct send_ctx *sctx, struct btrfs_path *path, struct btrfs_key *key, @@ -4598,9 +4870,7 @@ static int send_write_or_clone(struct send_ctx *sctx, int ret = 0; struct btrfs_file_extent_item *ei; u64 offset = key->offset; - u64 pos = 0; u64 len; - u32 l; u8 type; u64 bs = sctx->send_root->fs_info->sb->s_blocksize; @@ -4628,22 +4898,15 @@ static int send_write_or_clone(struct send_ctx *sctx, } if (clone_root && IS_ALIGNED(offset + len, bs)) { - ret = send_clone(sctx, offset, len, clone_root); - } else if (sctx->flags & BTRFS_SEND_FLAG_NO_FILE_DATA) { - ret = send_update_extent(sctx, offset, len); + u64 disk_byte; + u64 data_offset; + + disk_byte = btrfs_file_extent_disk_bytenr(path->nodes[0], ei); + data_offset = btrfs_file_extent_offset(path->nodes[0], ei); + ret = clone_range(sctx, clone_root, disk_byte, data_offset, + offset, len); } else { - while (pos < len) { - l = len - pos; - if (l > BTRFS_SEND_READ_SIZE) - l = BTRFS_SEND_READ_SIZE; - ret = send_write(sctx, pos + offset, l); - if (ret < 0) - goto out; - if (!ret) - break; - pos += ret; - } - ret = 0; + ret = send_extent_data(sctx, offset, len); } out: return ret; |