From 5d1646d90e1f2cceb9f0828f4b28318cd0ec7744 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sat, 27 Apr 2024 12:05:51 +0200 Subject: Adding upstream version 5.10.209. Signed-off-by: Daniel Baumann --- fs/reiserfs/tail_conversion.c | 318 ++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 318 insertions(+) create mode 100644 fs/reiserfs/tail_conversion.c (limited to 'fs/reiserfs/tail_conversion.c') diff --git a/fs/reiserfs/tail_conversion.c b/fs/reiserfs/tail_conversion.c new file mode 100644 index 000000000..b0ae088df --- /dev/null +++ b/fs/reiserfs/tail_conversion.c @@ -0,0 +1,318 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright 1999 Hans Reiser, see reiserfs/README for licensing and copyright + * details + */ + +#include +#include +#include +#include "reiserfs.h" + +/* + * access to tail : when one is going to read tail it must make sure, that is + * not running. direct2indirect and indirect2direct can not run concurrently + */ + +/* + * Converts direct items to an unformatted node. Panics if file has no + * tail. -ENOSPC if no disk space for conversion + */ +/* + * path points to first direct item of the file regardless of how many of + * them are there + */ +int direct2indirect(struct reiserfs_transaction_handle *th, struct inode *inode, + struct treepath *path, struct buffer_head *unbh, + loff_t tail_offset) +{ + struct super_block *sb = inode->i_sb; + struct buffer_head *up_to_date_bh; + struct item_head *p_le_ih = tp_item_head(path); + unsigned long total_tail = 0; + + /* Key to search for the last byte of the converted item. */ + struct cpu_key end_key; + + /* + * new indirect item to be inserted or key + * of unfm pointer to be pasted + */ + struct item_head ind_ih; + int blk_size; + /* returned value for reiserfs_insert_item and clones */ + int retval; + /* Handle on an unformatted node that will be inserted in the tree. */ + unp_t unfm_ptr; + + BUG_ON(!th->t_trans_id); + + REISERFS_SB(sb)->s_direct2indirect++; + + blk_size = sb->s_blocksize; + + /* + * and key to search for append or insert pointer to the new + * unformatted node. + */ + copy_item_head(&ind_ih, p_le_ih); + set_le_ih_k_offset(&ind_ih, tail_offset); + set_le_ih_k_type(&ind_ih, TYPE_INDIRECT); + + /* Set the key to search for the place for new unfm pointer */ + make_cpu_key(&end_key, inode, tail_offset, TYPE_INDIRECT, 4); + + /* FIXME: we could avoid this */ + if (search_for_position_by_key(sb, &end_key, path) == POSITION_FOUND) { + reiserfs_error(sb, "PAP-14030", + "pasted or inserted byte exists in " + "the tree %K. Use fsck to repair.", &end_key); + pathrelse(path); + return -EIO; + } + + p_le_ih = tp_item_head(path); + + unfm_ptr = cpu_to_le32(unbh->b_blocknr); + + if (is_statdata_le_ih(p_le_ih)) { + /* Insert new indirect item. */ + set_ih_free_space(&ind_ih, 0); /* delete at nearest future */ + put_ih_item_len(&ind_ih, UNFM_P_SIZE); + PATH_LAST_POSITION(path)++; + retval = + reiserfs_insert_item(th, path, &end_key, &ind_ih, inode, + (char *)&unfm_ptr); + } else { + /* Paste into last indirect item of an object. */ + retval = reiserfs_paste_into_item(th, path, &end_key, inode, + (char *)&unfm_ptr, + UNFM_P_SIZE); + } + if (retval) { + return retval; + } + /* + * note: from here there are two keys which have matching first + * three key components. They only differ by the fourth one. + */ + + /* Set the key to search for the direct items of the file */ + make_cpu_key(&end_key, inode, max_reiserfs_offset(inode), TYPE_DIRECT, + 4); + + /* + * Move bytes from the direct items to the new unformatted node + * and delete them. + */ + while (1) { + int tail_size; + + /* + * end_key.k_offset is set so, that we will always have found + * last item of the file + */ + if (search_for_position_by_key(sb, &end_key, path) == + POSITION_FOUND) + reiserfs_panic(sb, "PAP-14050", + "direct item (%K) not found", &end_key); + p_le_ih = tp_item_head(path); + RFALSE(!is_direct_le_ih(p_le_ih), + "vs-14055: direct item expected(%K), found %h", + &end_key, p_le_ih); + tail_size = (le_ih_k_offset(p_le_ih) & (blk_size - 1)) + + ih_item_len(p_le_ih) - 1; + + /* + * we only send the unbh pointer if the buffer is not + * up to date. this avoids overwriting good data from + * writepage() with old data from the disk or buffer cache + * Special case: unbh->b_page will be NULL if we are coming + * through DIRECT_IO handler here. + */ + if (!unbh->b_page || buffer_uptodate(unbh) + || PageUptodate(unbh->b_page)) { + up_to_date_bh = NULL; + } else { + up_to_date_bh = unbh; + } + retval = reiserfs_delete_item(th, path, &end_key, inode, + up_to_date_bh); + + total_tail += retval; + + /* done: file does not have direct items anymore */ + if (tail_size == retval) + break; + + } + /* + * if we've copied bytes from disk into the page, we need to zero + * out the unused part of the block (it was not up to date before) + */ + if (up_to_date_bh) { + unsigned pgoff = + (tail_offset + total_tail - 1) & (PAGE_SIZE - 1); + char *kaddr = kmap_atomic(up_to_date_bh->b_page); + memset(kaddr + pgoff, 0, blk_size - total_tail); + kunmap_atomic(kaddr); + } + + REISERFS_I(inode)->i_first_direct_byte = U32_MAX; + + return 0; +} + +/* stolen from fs/buffer.c */ +void reiserfs_unmap_buffer(struct buffer_head *bh) +{ + lock_buffer(bh); + if (buffer_journaled(bh) || buffer_journal_dirty(bh)) { + BUG(); + } + clear_buffer_dirty(bh); + /* + * Remove the buffer from whatever list it belongs to. We are mostly + * interested in removing it from per-sb j_dirty_buffers list, to avoid + * BUG() on attempt to write not mapped buffer + */ + if ((!list_empty(&bh->b_assoc_buffers) || bh->b_private) && bh->b_page) { + struct inode *inode = bh->b_page->mapping->host; + struct reiserfs_journal *j = SB_JOURNAL(inode->i_sb); + spin_lock(&j->j_dirty_buffers_lock); + list_del_init(&bh->b_assoc_buffers); + reiserfs_free_jh(bh); + spin_unlock(&j->j_dirty_buffers_lock); + } + clear_buffer_mapped(bh); + clear_buffer_req(bh); + clear_buffer_new(bh); + bh->b_bdev = NULL; + unlock_buffer(bh); +} + +/* + * this first locks inode (neither reads nor sync are permitted), + * reads tail through page cache, insert direct item. When direct item + * inserted successfully inode is left locked. Return value is always + * what we expect from it (number of cut bytes). But when tail remains + * in the unformatted node, we set mode to SKIP_BALANCING and unlock + * inode + */ +int indirect2direct(struct reiserfs_transaction_handle *th, + struct inode *inode, struct page *page, + struct treepath *path, /* path to the indirect item. */ + const struct cpu_key *item_key, /* Key to look for + * unformatted node + * pointer to be cut. */ + loff_t n_new_file_size, /* New file size. */ + char *mode) +{ + struct super_block *sb = inode->i_sb; + struct item_head s_ih; + unsigned long block_size = sb->s_blocksize; + char *tail; + int tail_len, round_tail_len; + loff_t pos, pos1; /* position of first byte of the tail */ + struct cpu_key key; + + BUG_ON(!th->t_trans_id); + + REISERFS_SB(sb)->s_indirect2direct++; + + *mode = M_SKIP_BALANCING; + + /* store item head path points to. */ + copy_item_head(&s_ih, tp_item_head(path)); + + tail_len = (n_new_file_size & (block_size - 1)); + if (get_inode_sd_version(inode) == STAT_DATA_V2) + round_tail_len = ROUND_UP(tail_len); + else + round_tail_len = tail_len; + + pos = + le_ih_k_offset(&s_ih) - 1 + (ih_item_len(&s_ih) / UNFM_P_SIZE - + 1) * sb->s_blocksize; + pos1 = pos; + + /* + * we are protected by i_mutex. The tail can not disapper, not + * append can be done either + * we are in truncate or packing tail in file_release + */ + + tail = (char *)kmap(page); /* this can schedule */ + + if (path_changed(&s_ih, path)) { + /* re-search indirect item */ + if (search_for_position_by_key(sb, item_key, path) + == POSITION_NOT_FOUND) + reiserfs_panic(sb, "PAP-5520", + "item to be converted %K does not exist", + item_key); + copy_item_head(&s_ih, tp_item_head(path)); +#ifdef CONFIG_REISERFS_CHECK + pos = le_ih_k_offset(&s_ih) - 1 + + (ih_item_len(&s_ih) / UNFM_P_SIZE - + 1) * sb->s_blocksize; + if (pos != pos1) + reiserfs_panic(sb, "vs-5530", "tail position " + "changed while we were reading it"); +#endif + } + + /* Set direct item header to insert. */ + make_le_item_head(&s_ih, NULL, get_inode_item_key_version(inode), + pos1 + 1, TYPE_DIRECT, round_tail_len, + 0xffff /*ih_free_space */ ); + + /* + * we want a pointer to the first byte of the tail in the page. + * the page was locked and this part of the page was up to date when + * indirect2direct was called, so we know the bytes are still valid + */ + tail = tail + (pos & (PAGE_SIZE - 1)); + + PATH_LAST_POSITION(path)++; + + key = *item_key; + set_cpu_key_k_type(&key, TYPE_DIRECT); + key.key_length = 4; + /* Insert tail as new direct item in the tree */ + if (reiserfs_insert_item(th, path, &key, &s_ih, inode, + tail ? tail : NULL) < 0) { + /* + * No disk memory. So we can not convert last unformatted node + * to the direct item. In this case we used to adjust + * indirect items's ih_free_space. Now ih_free_space is not + * used, it would be ideal to write zeros to corresponding + * unformatted node. For now i_size is considered as guard for + * going out of file size + */ + kunmap(page); + return block_size - round_tail_len; + } + kunmap(page); + + /* make sure to get the i_blocks changes from reiserfs_insert_item */ + reiserfs_update_sd(th, inode); + + /* + * note: we have now the same as in above direct2indirect + * conversion: there are two keys which have matching first three + * key components. They only differ by the fourth one. + */ + + /* + * We have inserted new direct item and must remove last + * unformatted node. + */ + *mode = M_CUT; + + /* we store position of first direct item in the in-core inode */ + /* mark_file_with_tail (inode, pos1 + 1); */ + REISERFS_I(inode)->i_first_direct_byte = pos1 + 1; + + return block_size - round_tail_len; +} -- cgit v1.2.3