diff options
Diffstat (limited to 'fs/ext4/move_extent.c')
| -rw-r--r-- | fs/ext4/move_extent.c | 1799 |
1 files changed, 456 insertions, 1343 deletions
diff --git a/fs/ext4/move_extent.c b/fs/ext4/move_extent.c index e86dddbd8296..0550fd30fd10 100644 --- a/fs/ext4/move_extent.c +++ b/fs/ext4/move_extent.c @@ -1,151 +1,31 @@ +// SPDX-License-Identifier: LGPL-2.1 /* * Copyright (c) 2008,2009 NEC Software Tohoku, Ltd. * Written by Takashi Sato <t-sato@yk.jp.nec.com> * Akira Fujita <a-fujita@rs.jp.nec.com> - * - * This program is free software; you can redistribute it and/or modify it - * under the terms of version 2.1 of the GNU Lesser General Public License - * as published by the Free Software Foundation. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. */ #include <linux/fs.h> #include <linux/quotaops.h> #include <linux/slab.h> +#include <linux/sched/mm.h> #include "ext4_jbd2.h" #include "ext4.h" #include "ext4_extents.h" -/** - * get_ext_path - Find an extent path for designated logical block number. - * - * @inode: an inode which is searched - * @lblock: logical block number to find an extent path - * @path: pointer to an extent path pointer (for output) - * - * ext4_ext_find_extent wrapper. Return 0 on success, or a negative error value - * on failure. - */ -static inline int -get_ext_path(struct inode *inode, ext4_lblk_t lblock, - struct ext4_ext_path **orig_path) -{ - int ret = 0; - struct ext4_ext_path *path; - - path = ext4_ext_find_extent(inode, lblock, *orig_path); - if (IS_ERR(path)) - ret = PTR_ERR(path); - else if (path[ext_depth(inode)].p_ext == NULL) - ret = -ENODATA; - else - *orig_path = path; - - return ret; -} - -/** - * copy_extent_status - Copy the extent's initialization status - * - * @src: an extent for getting initialize status - * @dest: an extent to be set the status - */ -static void -copy_extent_status(struct ext4_extent *src, struct ext4_extent *dest) -{ - if (ext4_ext_is_uninitialized(src)) - ext4_ext_mark_uninitialized(dest); - else - dest->ee_len = cpu_to_le16(ext4_ext_get_actual_len(dest)); -} - -/** - * mext_next_extent - Search for the next extent and set it to "extent" - * - * @inode: inode which is searched - * @path: this will obtain data for the next extent - * @extent: pointer to the next extent we have just gotten - * - * Search the next extent in the array of ext4_ext_path structure (@path) - * and set it to ext4_extent structure (@extent). In addition, the member of - * @path (->p_ext) also points the next extent. Return 0 on success, 1 if - * ext4_ext_path structure refers to the last extent, or a negative error - * value on failure. - */ -static int -mext_next_extent(struct inode *inode, struct ext4_ext_path *path, - struct ext4_extent **extent) -{ - struct ext4_extent_header *eh; - int ppos, leaf_ppos = path->p_depth; - - ppos = leaf_ppos; - if (EXT_LAST_EXTENT(path[ppos].p_hdr) > path[ppos].p_ext) { - /* leaf block */ - *extent = ++path[ppos].p_ext; - path[ppos].p_block = ext4_ext_pblock(path[ppos].p_ext); - return 0; - } - - while (--ppos >= 0) { - if (EXT_LAST_INDEX(path[ppos].p_hdr) > - path[ppos].p_idx) { - int cur_ppos = ppos; - - /* index block */ - path[ppos].p_idx++; - path[ppos].p_block = ext4_idx_pblock(path[ppos].p_idx); - if (path[ppos+1].p_bh) - brelse(path[ppos+1].p_bh); - path[ppos+1].p_bh = - sb_bread(inode->i_sb, path[ppos].p_block); - if (!path[ppos+1].p_bh) - return -EIO; - path[ppos+1].p_hdr = - ext_block_hdr(path[ppos+1].p_bh); - - /* Halfway index block */ - while (++cur_ppos < leaf_ppos) { - path[cur_ppos].p_idx = - EXT_FIRST_INDEX(path[cur_ppos].p_hdr); - path[cur_ppos].p_block = - ext4_idx_pblock(path[cur_ppos].p_idx); - if (path[cur_ppos+1].p_bh) - brelse(path[cur_ppos+1].p_bh); - path[cur_ppos+1].p_bh = sb_bread(inode->i_sb, - path[cur_ppos].p_block); - if (!path[cur_ppos+1].p_bh) - return -EIO; - path[cur_ppos+1].p_hdr = - ext_block_hdr(path[cur_ppos+1].p_bh); - } - - path[leaf_ppos].p_ext = *extent = NULL; +#include <trace/events/ext4.h> - eh = path[leaf_ppos].p_hdr; - if (le16_to_cpu(eh->eh_entries) == 0) - /* empty leaf is found */ - return -ENODATA; - - /* leaf block */ - path[leaf_ppos].p_ext = *extent = - EXT_FIRST_EXTENT(path[leaf_ppos].p_hdr); - path[leaf_ppos].p_block = - ext4_ext_pblock(path[leaf_ppos].p_ext); - return 0; - } - } - /* We found the last extent */ - return 1; -} +struct mext_data { + struct inode *orig_inode; /* Origin file inode */ + struct inode *donor_inode; /* Donor file inode */ + struct ext4_map_blocks orig_map;/* Origin file's move mapping */ + ext4_lblk_t donor_lblk; /* Start block of the donor file */ +}; /** - * ext4_double_down_write_data_sem - Acquire two inodes' write lock - * of i_data_sem + * ext4_double_down_write_data_sem() - write lock two inodes's i_data_sem + * @first: inode to be locked + * @second: inode to be locked * * Acquire write lock of i_data_sem of the two inodes */ @@ -154,11 +34,10 @@ ext4_double_down_write_data_sem(struct inode *first, struct inode *second) { if (first < second) { down_write(&EXT4_I(first)->i_data_sem); - down_write_nested(&EXT4_I(second)->i_data_sem, SINGLE_DEPTH_NESTING); + down_write_nested(&EXT4_I(second)->i_data_sem, I_DATA_SEM_OTHER); } else { down_write(&EXT4_I(second)->i_data_sem); - down_write_nested(&EXT4_I(first)->i_data_sem, SINGLE_DEPTH_NESTING); - + down_write_nested(&EXT4_I(first)->i_data_sem, I_DATA_SEM_OTHER); } } @@ -177,951 +56,444 @@ ext4_double_up_write_data_sem(struct inode *orig_inode, up_write(&EXT4_I(donor_inode)->i_data_sem); } -/** - * mext_insert_across_blocks - Insert extents across leaf block - * - * @handle: journal handle - * @orig_inode: original inode - * @o_start: first original extent to be changed - * @o_end: last original extent to be changed - * @start_ext: first new extent to be inserted - * @new_ext: middle of new extent to be inserted - * @end_ext: last new extent to be inserted - * - * Allocate a new leaf block and insert extents into it. Return 0 on success, - * or a negative error value on failure. - */ -static int -mext_insert_across_blocks(handle_t *handle, struct inode *orig_inode, - struct ext4_extent *o_start, struct ext4_extent *o_end, - struct ext4_extent *start_ext, struct ext4_extent *new_ext, - struct ext4_extent *end_ext) +/* Grab and lock folio on both @inode1 and @inode2 by inode order. */ +static int mext_folio_double_lock(struct inode *inode1, struct inode *inode2, + pgoff_t index1, pgoff_t index2, size_t len, + struct folio *folio[2]) { - struct ext4_ext_path *orig_path = NULL; - ext4_lblk_t eblock = 0; - int new_flag = 0; - int end_flag = 0; - int err = 0; - - if (start_ext->ee_len && new_ext->ee_len && end_ext->ee_len) { - if (o_start == o_end) { - - /* start_ext new_ext end_ext - * donor |---------|-----------|--------| - * orig |------------------------------| - */ - end_flag = 1; - } else { - - /* start_ext new_ext end_ext - * donor |---------|----------|---------| - * orig |---------------|--------------| - */ - o_end->ee_block = end_ext->ee_block; - o_end->ee_len = end_ext->ee_len; - ext4_ext_store_pblock(o_end, ext4_ext_pblock(end_ext)); - } + struct address_space *mapping[2]; + unsigned int flags; + fgf_t fgp_flags = FGP_WRITEBEGIN; - o_start->ee_len = start_ext->ee_len; - eblock = le32_to_cpu(start_ext->ee_block); - new_flag = 1; - - } else if (start_ext->ee_len && new_ext->ee_len && - !end_ext->ee_len && o_start == o_end) { - - /* start_ext new_ext - * donor |--------------|---------------| - * orig |------------------------------| - */ - o_start->ee_len = start_ext->ee_len; - eblock = le32_to_cpu(start_ext->ee_block); - new_flag = 1; - - } else if (!start_ext->ee_len && new_ext->ee_len && - end_ext->ee_len && o_start == o_end) { - - /* new_ext end_ext - * donor |--------------|---------------| - * orig |------------------------------| - */ - o_end->ee_block = end_ext->ee_block; - o_end->ee_len = end_ext->ee_len; - ext4_ext_store_pblock(o_end, ext4_ext_pblock(end_ext)); - - /* - * Set 0 to the extent block if new_ext was - * the first block. - */ - if (new_ext->ee_block) - eblock = le32_to_cpu(new_ext->ee_block); - - new_flag = 1; + BUG_ON(!inode1 || !inode2); + if (inode1 < inode2) { + mapping[0] = inode1->i_mapping; + mapping[1] = inode2->i_mapping; } else { - ext4_debug("ext4 move extent: Unexpected insert case\n"); - return -EIO; + swap(index1, index2); + mapping[0] = inode2->i_mapping; + mapping[1] = inode1->i_mapping; } - if (new_flag) { - err = get_ext_path(orig_inode, eblock, &orig_path); - if (err) - goto out; - - if (ext4_ext_insert_extent(handle, orig_inode, - orig_path, new_ext, 0)) - goto out; + flags = memalloc_nofs_save(); + fgp_flags |= fgf_set_order(len); + folio[0] = __filemap_get_folio(mapping[0], index1, fgp_flags, + mapping_gfp_mask(mapping[0])); + if (IS_ERR(folio[0])) { + memalloc_nofs_restore(flags); + return PTR_ERR(folio[0]); } - if (end_flag) { - err = get_ext_path(orig_inode, - le32_to_cpu(end_ext->ee_block) - 1, &orig_path); - if (err) - goto out; - - if (ext4_ext_insert_extent(handle, orig_inode, - orig_path, end_ext, 0)) - goto out; + folio[1] = __filemap_get_folio(mapping[1], index2, fgp_flags, + mapping_gfp_mask(mapping[1])); + memalloc_nofs_restore(flags); + if (IS_ERR(folio[1])) { + folio_unlock(folio[0]); + folio_put(folio[0]); + return PTR_ERR(folio[1]); } -out: - if (orig_path) { - ext4_ext_drop_refs(orig_path); - kfree(orig_path); - } - - return err; + /* + * __filemap_get_folio() may not wait on folio's writeback if + * BDI not demand that. But it is reasonable to be very conservative + * here and explicitly wait on folio's writeback + */ + folio_wait_writeback(folio[0]); + folio_wait_writeback(folio[1]); + if (inode1 > inode2) + swap(folio[0], folio[1]); + return 0; } -/** - * mext_insert_inside_block - Insert new extent to the extent block - * - * @o_start: first original extent to be moved - * @o_end: last original extent to be moved - * @start_ext: first new extent to be inserted - * @new_ext: middle of new extent to be inserted - * @end_ext: last new extent to be inserted - * @eh: extent header of target leaf block - * @range_to_move: used to decide how to insert extent - * - * Insert extents into the leaf block. The extent (@o_start) is overwritten - * by inserted extents. - */ -static void -mext_insert_inside_block(struct ext4_extent *o_start, - struct ext4_extent *o_end, - struct ext4_extent *start_ext, - struct ext4_extent *new_ext, - struct ext4_extent *end_ext, - struct ext4_extent_header *eh, - int range_to_move) +static void mext_folio_double_unlock(struct folio *folio[2]) { - int i = 0; - unsigned long len; - - /* Move the existing extents */ - if (range_to_move && o_end < EXT_LAST_EXTENT(eh)) { - len = (unsigned long)(EXT_LAST_EXTENT(eh) + 1) - - (unsigned long)(o_end + 1); - memmove(o_end + 1 + range_to_move, o_end + 1, len); - } - - /* Insert start entry */ - if (start_ext->ee_len) - o_start[i++].ee_len = start_ext->ee_len; - - /* Insert new entry */ - if (new_ext->ee_len) { - o_start[i] = *new_ext; - ext4_ext_store_pblock(&o_start[i++], ext4_ext_pblock(new_ext)); - } - - /* Insert end entry */ - if (end_ext->ee_len) - o_start[i] = *end_ext; - - /* Increment the total entries counter on the extent block */ - le16_add_cpu(&eh->eh_entries, range_to_move); + folio_unlock(folio[0]); + folio_put(folio[0]); + folio_unlock(folio[1]); + folio_put(folio[1]); } -/** - * mext_insert_extents - Insert new extent - * - * @handle: journal handle - * @orig_inode: original inode - * @orig_path: path indicates first extent to be changed - * @o_start: first original extent to be changed - * @o_end: last original extent to be changed - * @start_ext: first new extent to be inserted - * @new_ext: middle of new extent to be inserted - * @end_ext: last new extent to be inserted - * - * Call the function to insert extents. If we cannot add more extents into - * the leaf block, we call mext_insert_across_blocks() to create a - * new leaf block. Otherwise call mext_insert_inside_block(). Return 0 - * on success, or a negative error value on failure. - */ -static int -mext_insert_extents(handle_t *handle, struct inode *orig_inode, - struct ext4_ext_path *orig_path, - struct ext4_extent *o_start, - struct ext4_extent *o_end, - struct ext4_extent *start_ext, - struct ext4_extent *new_ext, - struct ext4_extent *end_ext) +/* Force folio buffers uptodate w/o dropping folio's lock */ +static int mext_folio_mkuptodate(struct folio *folio, size_t from, size_t to) { - struct ext4_extent_header *eh; - unsigned long need_slots, slots_range; - int range_to_move, depth, ret; + struct inode *inode = folio->mapping->host; + sector_t block; + struct buffer_head *bh, *head; + unsigned int blocksize, block_start, block_end; + int nr = 0; + bool partial = false; - /* - * The extents need to be inserted - * start_extent + new_extent + end_extent. - */ - need_slots = (start_ext->ee_len ? 1 : 0) + (end_ext->ee_len ? 1 : 0) + - (new_ext->ee_len ? 1 : 0); - - /* The number of slots between start and end */ - slots_range = ((unsigned long)(o_end + 1) - (unsigned long)o_start + 1) - / sizeof(struct ext4_extent); - - /* Range to move the end of extent */ - range_to_move = need_slots - slots_range; - depth = orig_path->p_depth; - orig_path += depth; - eh = orig_path->p_hdr; - - if (depth) { - /* Register to journal */ - ret = ext4_journal_get_write_access(handle, orig_path->p_bh); - if (ret) - return ret; - } + BUG_ON(!folio_test_locked(folio)); + BUG_ON(folio_test_writeback(folio)); - /* Expansion */ - if (range_to_move > 0 && - (range_to_move > le16_to_cpu(eh->eh_max) - - le16_to_cpu(eh->eh_entries))) { + if (folio_test_uptodate(folio)) + return 0; - ret = mext_insert_across_blocks(handle, orig_inode, o_start, - o_end, start_ext, new_ext, end_ext); - if (ret < 0) - return ret; - } else - mext_insert_inside_block(o_start, o_end, start_ext, new_ext, - end_ext, eh, range_to_move); + blocksize = i_blocksize(inode); + head = folio_buffers(folio); + if (!head) + head = create_empty_buffers(folio, blocksize, 0); + + block = folio_pos(folio) >> inode->i_blkbits; + block_end = 0; + bh = head; + do { + block_start = block_end; + block_end = block_start + blocksize; + if (block_end <= from || block_start >= to) { + if (!buffer_uptodate(bh)) + partial = true; + continue; + } + if (buffer_uptodate(bh)) + continue; + if (!buffer_mapped(bh)) { + int err = ext4_get_block(inode, block, bh, 0); + if (err) + return err; + if (!buffer_mapped(bh)) { + folio_zero_range(folio, block_start, blocksize); + set_buffer_uptodate(bh); + continue; + } + } + lock_buffer(bh); + if (buffer_uptodate(bh)) { + unlock_buffer(bh); + continue; + } + ext4_read_bh_nowait(bh, 0, NULL, false); + nr++; + } while (block++, (bh = bh->b_this_page) != head); - return ext4_ext_dirty(handle, orig_inode, orig_path); + /* No io required */ + if (!nr) + goto out; + + bh = head; + do { + if (bh_offset(bh) + blocksize <= from) + continue; + if (bh_offset(bh) >= to) + break; + wait_on_buffer(bh); + if (buffer_uptodate(bh)) + continue; + return -EIO; + } while ((bh = bh->b_this_page) != head); +out: + if (!partial) + folio_mark_uptodate(folio); + return 0; } -/** - * mext_leaf_block - Move one leaf extent block into the inode. - * - * @handle: journal handle - * @orig_inode: original inode - * @orig_path: path indicates first extent to be changed - * @dext: donor extent - * @from: start offset on the target file - * - * In order to insert extents into the leaf block, we must divide the extent - * in the leaf block into three extents. The one is located to be inserted - * extents, and the others are located around it. - * - * Therefore, this function creates structures to save extents of the leaf - * block, and inserts extents by calling mext_insert_extents() with - * created extents. Return 0 on success, or a negative error value on failure. +enum mext_move_type {MEXT_SKIP_EXTENT, MEXT_MOVE_EXTENT, MEXT_COPY_DATA}; + +/* + * Start to move extent between the origin inode and the donor inode, + * hold one folio for each inode and check the candidate moving extent + * mapping status again. */ -static int -mext_leaf_block(handle_t *handle, struct inode *orig_inode, - struct ext4_ext_path *orig_path, struct ext4_extent *dext, - ext4_lblk_t *from) +static int mext_move_begin(struct mext_data *mext, struct folio *folio[2], + enum mext_move_type *move_type) { - struct ext4_extent *oext, *o_start, *o_end, *prev_ext; - struct ext4_extent new_ext, start_ext, end_ext; - ext4_lblk_t new_ext_end; - int oext_alen, new_ext_alen, end_ext_alen; - int depth = ext_depth(orig_inode); + struct inode *orig_inode = mext->orig_inode; + struct inode *donor_inode = mext->donor_inode; + unsigned int blkbits = orig_inode->i_blkbits; + struct ext4_map_blocks donor_map = {0}; + loff_t orig_pos, donor_pos; + size_t move_len; int ret; - start_ext.ee_block = end_ext.ee_block = 0; - o_start = o_end = oext = orig_path[depth].p_ext; - oext_alen = ext4_ext_get_actual_len(oext); - start_ext.ee_len = end_ext.ee_len = 0; - - new_ext.ee_block = cpu_to_le32(*from); - ext4_ext_store_pblock(&new_ext, ext4_ext_pblock(dext)); - new_ext.ee_len = dext->ee_len; - new_ext_alen = ext4_ext_get_actual_len(&new_ext); - new_ext_end = le32_to_cpu(new_ext.ee_block) + new_ext_alen - 1; - - /* - * Case: original extent is first - * oext |--------| - * new_ext |--| - * start_ext |--| - */ - if (le32_to_cpu(oext->ee_block) < le32_to_cpu(new_ext.ee_block) && - le32_to_cpu(new_ext.ee_block) < - le32_to_cpu(oext->ee_block) + oext_alen) { - start_ext.ee_len = cpu_to_le16(le32_to_cpu(new_ext.ee_block) - - le32_to_cpu(oext->ee_block)); - start_ext.ee_block = oext->ee_block; - copy_extent_status(oext, &start_ext); - } else if (oext > EXT_FIRST_EXTENT(orig_path[depth].p_hdr)) { - prev_ext = oext - 1; - /* - * We can merge new_ext into previous extent, - * if these are contiguous and same extent type. - */ - if (ext4_can_extents_be_merged(orig_inode, prev_ext, - &new_ext)) { - o_start = prev_ext; - start_ext.ee_len = cpu_to_le16( - ext4_ext_get_actual_len(prev_ext) + - new_ext_alen); - start_ext.ee_block = oext->ee_block; - copy_extent_status(prev_ext, &start_ext); - new_ext.ee_len = 0; - } - } - - /* - * Case: new_ext_end must be less than oext - * oext |-----------| - * new_ext |-------| - */ - if (le32_to_cpu(oext->ee_block) + oext_alen - 1 < new_ext_end) { - EXT4_ERROR_INODE(orig_inode, - "new_ext_end(%u) should be less than or equal to " - "oext->ee_block(%u) + oext_alen(%d) - 1", - new_ext_end, le32_to_cpu(oext->ee_block), - oext_alen); - ret = -EIO; - goto out; - } + orig_pos = ((loff_t)mext->orig_map.m_lblk) << blkbits; + donor_pos = ((loff_t)mext->donor_lblk) << blkbits; + ret = mext_folio_double_lock(orig_inode, donor_inode, + orig_pos >> PAGE_SHIFT, donor_pos >> PAGE_SHIFT, + ((size_t)mext->orig_map.m_len) << blkbits, folio); + if (ret) + return ret; /* - * Case: new_ext is smaller than original extent - * oext |---------------| - * new_ext |-----------| - * end_ext |---| + * Check the origin inode's mapping information again under the + * folio lock, as we do not hold the i_data_sem at all times, and + * it may change during the concurrent write-back operation. */ - if (le32_to_cpu(oext->ee_block) <= new_ext_end && - new_ext_end < le32_to_cpu(oext->ee_block) + oext_alen - 1) { - end_ext.ee_len = - cpu_to_le16(le32_to_cpu(oext->ee_block) + - oext_alen - 1 - new_ext_end); - copy_extent_status(oext, &end_ext); - end_ext_alen = ext4_ext_get_actual_len(&end_ext); - ext4_ext_store_pblock(&end_ext, - (ext4_ext_pblock(o_end) + oext_alen - end_ext_alen)); - end_ext.ee_block = - cpu_to_le32(le32_to_cpu(o_end->ee_block) + - oext_alen - end_ext_alen); - } + if (mext->orig_map.m_seq != READ_ONCE(EXT4_I(orig_inode)->i_es_seq)) { + ret = -ESTALE; + goto error; + } + + /* Adjust the moving length according to the length of shorter folio. */ + move_len = umin(folio_pos(folio[0]) + folio_size(folio[0]) - orig_pos, + folio_pos(folio[1]) + folio_size(folio[1]) - donor_pos); + move_len >>= blkbits; + if (move_len < mext->orig_map.m_len) + mext->orig_map.m_len = move_len; + + donor_map.m_lblk = mext->donor_lblk; + donor_map.m_len = mext->orig_map.m_len; + donor_map.m_flags = 0; + ret = ext4_map_blocks(NULL, donor_inode, &donor_map, 0); + if (ret < 0) + goto error; + + /* Adjust the moving length according to the donor mapping length. */ + mext->orig_map.m_len = donor_map.m_len; + + /* Skip moving if the donor range is a hole or a delalloc extent. */ + if (!(donor_map.m_flags & (EXT4_MAP_MAPPED | EXT4_MAP_UNWRITTEN))) + *move_type = MEXT_SKIP_EXTENT; + /* If both mapping ranges are unwritten, no need to copy data. */ + else if ((mext->orig_map.m_flags & EXT4_MAP_UNWRITTEN) && + (donor_map.m_flags & EXT4_MAP_UNWRITTEN)) + *move_type = MEXT_MOVE_EXTENT; + else + *move_type = MEXT_COPY_DATA; - ret = mext_insert_extents(handle, orig_inode, orig_path, o_start, - o_end, &start_ext, &new_ext, &end_ext); -out: + return 0; +error: + mext_folio_double_unlock(folio); return ret; } -/** - * mext_calc_swap_extents - Calculate extents for extent swapping. - * - * @tmp_dext: the extent that will belong to the original inode - * @tmp_oext: the extent that will belong to the donor inode - * @orig_off: block offset of original inode - * @donor_off: block offset of donor inode - * @max_count: the maximum length of extents - * - * Return 0 on success, or a negative error value on failure. +/* + * Re-create the new moved mapping buffers of the original inode and commit + * the entire written range. */ -static int -mext_calc_swap_extents(struct ext4_extent *tmp_dext, - struct ext4_extent *tmp_oext, - ext4_lblk_t orig_off, ext4_lblk_t donor_off, - ext4_lblk_t max_count) +static int mext_folio_mkwrite(struct inode *inode, struct folio *folio, + size_t from, size_t to) { - ext4_lblk_t diff, orig_diff; - struct ext4_extent dext_old, oext_old; - - BUG_ON(orig_off != donor_off); - - /* original and donor extents have to cover the same block offset */ - if (orig_off < le32_to_cpu(tmp_oext->ee_block) || - le32_to_cpu(tmp_oext->ee_block) + - ext4_ext_get_actual_len(tmp_oext) - 1 < orig_off) - return -ENODATA; - - if (orig_off < le32_to_cpu(tmp_dext->ee_block) || - le32_to_cpu(tmp_dext->ee_block) + - ext4_ext_get_actual_len(tmp_dext) - 1 < orig_off) - return -ENODATA; - - dext_old = *tmp_dext; - oext_old = *tmp_oext; - - /* When tmp_dext is too large, pick up the target range. */ - diff = donor_off - le32_to_cpu(tmp_dext->ee_block); - - ext4_ext_store_pblock(tmp_dext, ext4_ext_pblock(tmp_dext) + diff); - le32_add_cpu(&tmp_dext->ee_block, diff); - le16_add_cpu(&tmp_dext->ee_len, -diff); - - if (max_count < ext4_ext_get_actual_len(tmp_dext)) - tmp_dext->ee_len = cpu_to_le16(max_count); - - orig_diff = orig_off - le32_to_cpu(tmp_oext->ee_block); - ext4_ext_store_pblock(tmp_oext, ext4_ext_pblock(tmp_oext) + orig_diff); + unsigned int blocksize = i_blocksize(inode); + struct buffer_head *bh, *head; + size_t block_start, block_end; + sector_t block; + int ret; - /* Adjust extent length if donor extent is larger than orig */ - if (ext4_ext_get_actual_len(tmp_dext) > - ext4_ext_get_actual_len(tmp_oext) - orig_diff) - tmp_dext->ee_len = cpu_to_le16(le16_to_cpu(tmp_oext->ee_len) - - orig_diff); + head = folio_buffers(folio); + if (!head) + head = create_empty_buffers(folio, blocksize, 0); - tmp_oext->ee_len = cpu_to_le16(ext4_ext_get_actual_len(tmp_dext)); + block = folio_pos(folio) >> inode->i_blkbits; + block_end = 0; + bh = head; + do { + block_start = block_end; + block_end = block_start + blocksize; + if (block_end <= from || block_start >= to) + continue; - copy_extent_status(&oext_old, tmp_dext); - copy_extent_status(&dext_old, tmp_oext); + ret = ext4_get_block(inode, block, bh, 0); + if (ret) + return ret; + } while (block++, (bh = bh->b_this_page) != head); + block_commit_write(folio, from, to); return 0; } -/** - * mext_check_coverage - Check that all extents in range has the same type - * - * @inode: inode in question - * @from: block offset of inode - * @count: block count to be checked - * @uninit: extents expected to be uninitialized - * @err: pointer to save error value - * - * Return 1 if all extents in range has expected type, and zero otherwise. - */ -static int -mext_check_coverage(struct inode *inode, ext4_lblk_t from, ext4_lblk_t count, - int uninit, int *err) -{ - struct ext4_ext_path *path = NULL; - struct ext4_extent *ext; - int ret = 0; - ext4_lblk_t last = from + count; - while (from < last) { - *err = get_ext_path(inode, from, &path); - if (*err) - goto out; - ext = path[ext_depth(inode)].p_ext; - if (uninit != ext4_ext_is_uninitialized(ext)) - goto out; - from += ext4_ext_get_actual_len(ext); - ext4_ext_drop_refs(path); - } - ret = 1; -out: - if (path) { - ext4_ext_drop_refs(path); - kfree(path); - } - return ret; -} - -/** - * mext_replace_branches - Replace original extents with new extents - * - * @handle: journal handle - * @orig_inode: original inode - * @donor_inode: donor inode - * @from: block offset of orig_inode - * @count: block count to be replaced - * @err: pointer to save return value - * - * Replace original inode extents and donor inode extents page by page. - * We implement this replacement in the following three steps: - * 1. Save the block information of original and donor inodes into - * dummy extents. - * 2. Change the block information of original inode to point at the - * donor inode blocks. - * 3. Change the block information of donor inode to point at the saved - * original inode blocks in the dummy extents. - * - * Return replaced block count. +/* + * Save the data in original inode extent blocks and replace one folio size + * aligned original inode extent with one or one partial donor inode extent, + * and then write out the saved data in new original inode blocks. Pass out + * the replaced block count through m_len. Return 0 on success, and an error + * code otherwise. */ -static int -mext_replace_branches(handle_t *handle, struct inode *orig_inode, - struct inode *donor_inode, ext4_lblk_t from, - ext4_lblk_t count, int *err) +static int mext_move_extent(struct mext_data *mext, u64 *m_len) { - struct ext4_ext_path *orig_path = NULL; - struct ext4_ext_path *donor_path = NULL; - struct ext4_extent *oext, *dext; - struct ext4_extent tmp_dext, tmp_oext; - ext4_lblk_t orig_off = from, donor_off = from; - int depth; - int replaced_count = 0; - int dext_alen; - - *err = ext4_es_remove_extent(orig_inode, from, count); - if (*err) - goto out; - - *err = ext4_es_remove_extent(donor_inode, from, count); - if (*err) - goto out; - - /* Get the original extent for the block "orig_off" */ - *err = get_ext_path(orig_inode, orig_off, &orig_path); - if (*err) - goto out; - - /* Get the donor extent for the head */ - *err = get_ext_path(donor_inode, donor_off, &donor_path); - if (*err) - goto out; - depth = ext_depth(orig_inode); - oext = orig_path[depth].p_ext; - tmp_oext = *oext; - - depth = ext_depth(donor_inode); - dext = donor_path[depth].p_ext; - if (unlikely(!dext)) - goto missing_donor_extent; - tmp_dext = *dext; - - *err = mext_calc_swap_extents(&tmp_dext, &tmp_oext, orig_off, - donor_off, count); - if (*err) + struct inode *orig_inode = mext->orig_inode; + struct inode *donor_inode = mext->donor_inode; + struct ext4_map_blocks *orig_map = &mext->orig_map; + unsigned int blkbits = orig_inode->i_blkbits; + struct folio *folio[2] = {NULL, NULL}; + loff_t from, length; + enum mext_move_type move_type = 0; + handle_t *handle; + u64 r_len = 0; + unsigned int credits; + int ret, ret2; + + *m_len = 0; + trace_ext4_move_extent_enter(orig_inode, orig_map, donor_inode, + mext->donor_lblk); + credits = ext4_chunk_trans_extent(orig_inode, 0) * 2; + handle = ext4_journal_start(orig_inode, EXT4_HT_MOVE_EXTENTS, credits); + if (IS_ERR(handle)) { + ret = PTR_ERR(handle); goto out; + } - /* Loop for the donor extents */ - while (1) { - /* The extent for donor must be found. */ - if (unlikely(!dext)) { - missing_donor_extent: - EXT4_ERROR_INODE(donor_inode, - "The extent for donor must be found"); - *err = -EIO; - goto out; - } else if (donor_off != le32_to_cpu(tmp_dext.ee_block)) { - EXT4_ERROR_INODE(donor_inode, - "Donor offset(%u) and the first block of donor " - "extent(%u) should be equal", - donor_off, - le32_to_cpu(tmp_dext.ee_block)); - *err = -EIO; - goto out; - } - - /* Set donor extent to orig extent */ - *err = mext_leaf_block(handle, orig_inode, - orig_path, &tmp_dext, &orig_off); - if (*err) - goto out; - - /* Set orig extent to donor extent */ - *err = mext_leaf_block(handle, donor_inode, - donor_path, &tmp_oext, &donor_off); - if (*err) - goto out; - - dext_alen = ext4_ext_get_actual_len(&tmp_dext); - replaced_count += dext_alen; - donor_off += dext_alen; - orig_off += dext_alen; + ret = mext_move_begin(mext, folio, &move_type); + if (ret) + goto stop_handle; - BUG_ON(replaced_count > count); - /* Already moved the expected blocks */ - if (replaced_count >= count) - break; + if (move_type == MEXT_SKIP_EXTENT) + goto unlock; - if (orig_path) - ext4_ext_drop_refs(orig_path); - *err = get_ext_path(orig_inode, orig_off, &orig_path); - if (*err) - goto out; - depth = ext_depth(orig_inode); - oext = orig_path[depth].p_ext; - tmp_oext = *oext; - - if (donor_path) - ext4_ext_drop_refs(donor_path); - *err = get_ext_path(donor_inode, donor_off, &donor_path); - if (*err) - goto out; - depth = ext_depth(donor_inode); - dext = donor_path[depth].p_ext; - tmp_dext = *dext; + /* + * Copy the data. First, read the original inode data into the page + * cache. Then, release the existing mapping relationships and swap + * the extent. Finally, re-establish the new mapping relationships + * and dirty the page cache. + */ + if (move_type == MEXT_COPY_DATA) { + from = offset_in_folio(folio[0], + ((loff_t)orig_map->m_lblk) << blkbits); + length = ((loff_t)orig_map->m_len) << blkbits; - *err = mext_calc_swap_extents(&tmp_dext, &tmp_oext, orig_off, - donor_off, count - replaced_count); - if (*err) - goto out; + ret = mext_folio_mkuptodate(folio[0], from, from + length); + if (ret) + goto unlock; } -out: - if (orig_path) { - ext4_ext_drop_refs(orig_path); - kfree(orig_path); - } - if (donor_path) { - ext4_ext_drop_refs(donor_path); - kfree(donor_path); + if (!filemap_release_folio(folio[0], 0) || + !filemap_release_folio(folio[1], 0)) { + ret = -EBUSY; + goto unlock; } - return replaced_count; -} - -/** - * mext_page_double_lock - Grab and lock pages on both @inode1 and @inode2 - * - * @inode1: the inode structure - * @inode2: the inode structure - * @index: page index - * @page: result page vector - * - * Grab two locked pages for inode's by inode order - */ -static int -mext_page_double_lock(struct inode *inode1, struct inode *inode2, - pgoff_t index, struct page *page[2]) -{ - struct address_space *mapping[2]; - unsigned fl = AOP_FLAG_NOFS; + /* Move extent */ + ext4_double_down_write_data_sem(orig_inode, donor_inode); + *m_len = ext4_swap_extents(handle, orig_inode, donor_inode, + orig_map->m_lblk, mext->donor_lblk, + orig_map->m_len, 1, &ret); + ext4_double_up_write_data_sem(orig_inode, donor_inode); - BUG_ON(!inode1 || !inode2); - if (inode1 < inode2) { - mapping[0] = inode1->i_mapping; - mapping[1] = inode2->i_mapping; - } else { - mapping[0] = inode2->i_mapping; - mapping[1] = inode1->i_mapping; - } + /* A short-length swap cannot occur after a successful swap extent. */ + if (WARN_ON_ONCE(!ret && (*m_len != orig_map->m_len))) + ret = -EIO; - page[0] = grab_cache_page_write_begin(mapping[0], index, fl); - if (!page[0]) - return -ENOMEM; + if (!(*m_len) || (move_type == MEXT_MOVE_EXTENT)) + goto unlock; - page[1] = grab_cache_page_write_begin(mapping[1], index, fl); - if (!page[1]) { - unlock_page(page[0]); - page_cache_release(page[0]); - return -ENOMEM; + /* Copy data */ + length = (*m_len) << blkbits; + ret2 = mext_folio_mkwrite(orig_inode, folio[0], from, from + length); + if (ret2) { + if (!ret) + ret = ret2; + goto repair_branches; } /* - * grab_cache_page_write_begin() may not wait on page's writeback if - * BDI not demand that. But it is reasonable to be very conservative - * here and explicitly wait on page's writeback + * Even in case of data=writeback it is reasonable to pin + * inode to transaction, to prevent unexpected data loss. */ - wait_on_page_writeback(page[0]); - wait_on_page_writeback(page[1]); - if (inode1 > inode2) { - struct page *tmp; - tmp = page[0]; - page[0] = page[1]; - page[1] = tmp; + ret2 = ext4_jbd2_inode_add_write(handle, orig_inode, + ((loff_t)orig_map->m_lblk) << blkbits, length); + if (!ret) + ret = ret2; +unlock: + mext_folio_double_unlock(folio); +stop_handle: + ext4_journal_stop(handle); +out: + trace_ext4_move_extent_exit(orig_inode, orig_map->m_lblk, donor_inode, + mext->donor_lblk, orig_map->m_len, *m_len, + move_type, ret); + return ret; + +repair_branches: + ret2 = 0; + r_len = ext4_swap_extents(handle, donor_inode, orig_inode, + mext->donor_lblk, orig_map->m_lblk, + *m_len, 0, &ret2); + if (ret2 || r_len != *m_len) { + ext4_error_inode_block(orig_inode, (sector_t)(orig_map->m_lblk), + EIO, "Unable to copy data block, data will be lost!"); + ret = -EIO; } - return 0; + *m_len = 0; + goto unlock; } -/* Force page buffers uptodate w/o dropping page's lock */ -static int -mext_page_mkuptodate(struct page *page, unsigned from, unsigned to) +/* + * Check the validity of the basic filesystem environment and the + * inodes' support status. + */ +static int mext_check_validity(struct inode *orig_inode, + struct inode *donor_inode) { - struct inode *inode = page->mapping->host; - sector_t block; - struct buffer_head *bh, *head, *arr[MAX_BUF_PER_PAGE]; - unsigned int blocksize, block_start, block_end; - int i, err, nr = 0, partial = 0; - BUG_ON(!PageLocked(page)); - BUG_ON(PageWriteback(page)); + struct super_block *sb = orig_inode->i_sb; - if (PageUptodate(page)) - return 0; - - blocksize = 1 << inode->i_blkbits; - if (!page_has_buffers(page)) - create_empty_buffers(page, blocksize, 0); + /* origin and donor should be different inodes */ + if (orig_inode == donor_inode) { + ext4_debug("ext4 move extent: The argument files should not be same inode [ino:orig %lu, donor %lu]\n", + orig_inode->i_ino, donor_inode->i_ino); + return -EINVAL; + } - head = page_buffers(page); - block = (sector_t)page->index << (PAGE_CACHE_SHIFT - inode->i_blkbits); - for (bh = head, block_start = 0; bh != head || !block_start; - block++, block_start = block_end, bh = bh->b_this_page) { - block_end = block_start + blocksize; - if (block_end <= from || block_start >= to) { - if (!buffer_uptodate(bh)) - partial = 1; - continue; - } - if (buffer_uptodate(bh)) - continue; - if (!buffer_mapped(bh)) { - err = ext4_get_block(inode, block, bh, 0); - if (err) { - SetPageError(page); - return err; - } - if (!buffer_mapped(bh)) { - zero_user(page, block_start, blocksize); - if (!err) - set_buffer_uptodate(bh); - continue; - } - } - BUG_ON(nr >= MAX_BUF_PER_PAGE); - arr[nr++] = bh; + /* origin and donor should belone to the same filesystem */ + if (orig_inode->i_sb != donor_inode->i_sb) { + ext4_debug("ext4 move extent: The argument files should be in same FS [ino:orig %lu, donor %lu]\n", + orig_inode->i_ino, donor_inode->i_ino); + return -EINVAL; } - /* No io required */ - if (!nr) - goto out; - for (i = 0; i < nr; i++) { - bh = arr[i]; - if (!bh_uptodate_or_lock(bh)) { - err = bh_submit_read(bh); - if (err) - return err; - } + /* Regular file check */ + if (!S_ISREG(orig_inode->i_mode) || !S_ISREG(donor_inode->i_mode)) { + ext4_debug("ext4 move extent: The argument files should be regular file [ino:orig %lu, donor %lu]\n", + orig_inode->i_ino, donor_inode->i_ino); + return -EINVAL; } -out: - if (!partial) - SetPageUptodate(page); - return 0; -} -/** - * move_extent_per_page - Move extent data per page - * - * @o_filp: file structure of original file - * @donor_inode: donor inode - * @orig_page_offset: page index on original file - * @data_offset_in_page: block index where data swapping starts - * @block_len_in_page: the number of blocks to be swapped - * @uninit: orig extent is uninitialized or not - * @err: pointer to save return value - * - * Save the data in original inode blocks and replace original inode extents - * with donor inode extents by calling mext_replace_branches(). - * Finally, write out the saved data in new original inode blocks. Return - * replaced block count. - */ -static int -move_extent_per_page(struct file *o_filp, struct inode *donor_inode, - pgoff_t orig_page_offset, int data_offset_in_page, - int block_len_in_page, int uninit, int *err) -{ - struct inode *orig_inode = file_inode(o_filp); - struct page *pagep[2] = {NULL, NULL}; - handle_t *handle; - ext4_lblk_t orig_blk_offset; - unsigned long blocksize = orig_inode->i_sb->s_blocksize; - unsigned int w_flags = 0; - unsigned int tmp_data_size, data_size, replaced_size; - int err2, jblocks, retries = 0; - int replaced_count = 0; - int from = data_offset_in_page << orig_inode->i_blkbits; - int blocks_per_page = PAGE_CACHE_SIZE >> orig_inode->i_blkbits; + if (ext4_has_feature_bigalloc(sb)) { + ext4_msg(sb, KERN_ERR, + "Online defrag not supported with bigalloc"); + return -EOPNOTSUPP; + } - /* - * It needs twice the amount of ordinary journal buffers because - * inode and donor_inode may change each different metadata blocks. - */ -again: - *err = 0; - jblocks = ext4_writepage_trans_blocks(orig_inode) * 2; - handle = ext4_journal_start(orig_inode, EXT4_HT_MOVE_EXTENTS, jblocks); - if (IS_ERR(handle)) { - *err = PTR_ERR(handle); - return 0; + if (IS_DAX(orig_inode)) { + ext4_msg(sb, KERN_ERR, + "Online defrag not supported with DAX"); + return -EOPNOTSUPP; } - if (segment_eq(get_fs(), KERNEL_DS)) - w_flags |= AOP_FLAG_UNINTERRUPTIBLE; - - orig_blk_offset = orig_page_offset * blocks_per_page + - data_offset_in_page; - - /* Calculate data_size */ - if ((orig_blk_offset + block_len_in_page - 1) == - ((orig_inode->i_size - 1) >> orig_inode->i_blkbits)) { - /* Replace the last block */ - tmp_data_size = orig_inode->i_size & (blocksize - 1); - /* - * If data_size equal zero, it shows data_size is multiples of - * blocksize. So we set appropriate value. - */ - if (tmp_data_size == 0) - tmp_data_size = blocksize; - - data_size = tmp_data_size + - ((block_len_in_page - 1) << orig_inode->i_blkbits); - } else - data_size = block_len_in_page << orig_inode->i_blkbits; - - replaced_size = data_size; - - *err = mext_page_double_lock(orig_inode, donor_inode, orig_page_offset, - pagep); - if (unlikely(*err < 0)) - goto stop_journal; /* - * If orig extent was uninitialized it can become initialized - * at any time after i_data_sem was dropped, in order to - * serialize with delalloc we have recheck extent while we - * hold page's lock, if it is still the case data copy is not - * necessary, just swap data blocks between orig and donor. + * TODO: it's not obvious how to swap blocks for inodes with full + * journaling enabled. */ - if (uninit) { - ext4_double_down_write_data_sem(orig_inode, donor_inode); - /* If any of extents in range became initialized we have to - * fallback to data copying */ - uninit = mext_check_coverage(orig_inode, orig_blk_offset, - block_len_in_page, 1, err); - if (*err) - goto drop_data_sem; - - uninit &= mext_check_coverage(donor_inode, orig_blk_offset, - block_len_in_page, 1, err); - if (*err) - goto drop_data_sem; - - if (!uninit) { - ext4_double_up_write_data_sem(orig_inode, donor_inode); - goto data_copy; - } - if ((page_has_private(pagep[0]) && - !try_to_release_page(pagep[0], 0)) || - (page_has_private(pagep[1]) && - !try_to_release_page(pagep[1], 0))) { - *err = -EBUSY; - goto drop_data_sem; - } - replaced_count = mext_replace_branches(handle, orig_inode, - donor_inode, orig_blk_offset, - block_len_in_page, err); - drop_data_sem: - ext4_double_up_write_data_sem(orig_inode, donor_inode); - goto unlock_pages; - } -data_copy: - *err = mext_page_mkuptodate(pagep[0], from, from + replaced_size); - if (*err) - goto unlock_pages; - - /* At this point all buffers in range are uptodate, old mapping layout - * is no longer required, try to drop it now. */ - if ((page_has_private(pagep[0]) && !try_to_release_page(pagep[0], 0)) || - (page_has_private(pagep[1]) && !try_to_release_page(pagep[1], 0))) { - *err = -EBUSY; - goto unlock_pages; + if (ext4_should_journal_data(orig_inode) || + ext4_should_journal_data(donor_inode)) { + ext4_msg(sb, KERN_ERR, + "Online defrag not supported with data journaling"); + return -EOPNOTSUPP; } - replaced_count = mext_replace_branches(handle, orig_inode, donor_inode, - orig_blk_offset, - block_len_in_page, err); - if (*err) { - if (replaced_count) { - block_len_in_page = replaced_count; - replaced_size = - block_len_in_page << orig_inode->i_blkbits; - } else - goto unlock_pages; + if (IS_ENCRYPTED(orig_inode) || IS_ENCRYPTED(donor_inode)) { + ext4_msg(sb, KERN_ERR, + "Online defrag not supported for encrypted files"); + return -EOPNOTSUPP; } - /* Perform all necessary steps similar write_begin()/write_end() - * but keeping in mind that i_size will not change */ - *err = __block_write_begin(pagep[0], from, replaced_size, - ext4_get_block); - if (!*err) - *err = block_commit_write(pagep[0], from, from + replaced_size); - - if (unlikely(*err < 0)) - goto repair_branches; - /* Even in case of data=writeback it is reasonable to pin - * inode to transaction, to prevent unexpected data loss */ - *err = ext4_jbd2_file_inode(handle, orig_inode); - -unlock_pages: - unlock_page(pagep[0]); - page_cache_release(pagep[0]); - unlock_page(pagep[1]); - page_cache_release(pagep[1]); -stop_journal: - ext4_journal_stop(handle); - /* Buffer was busy because probably is pinned to journal transaction, - * force transaction commit may help to free it. */ - if (*err == -EBUSY && ext4_should_retry_alloc(orig_inode->i_sb, - &retries)) - goto again; - return replaced_count; - -repair_branches: - /* - * This should never ever happen! - * Extents are swapped already, but we are not able to copy data. - * Try to swap extents to it's original places - */ - ext4_double_down_write_data_sem(orig_inode, donor_inode); - replaced_count = mext_replace_branches(handle, donor_inode, orig_inode, - orig_blk_offset, - block_len_in_page, &err2); - ext4_double_up_write_data_sem(orig_inode, donor_inode); - if (replaced_count != block_len_in_page) { - EXT4_ERROR_INODE_BLOCK(orig_inode, (sector_t)(orig_blk_offset), - "Unable to copy data block," - " data will be lost."); - *err = -EIO; + /* Ext4 move extent supports only extent based file */ + if (!(ext4_test_inode_flag(orig_inode, EXT4_INODE_EXTENTS)) || + !(ext4_test_inode_flag(donor_inode, EXT4_INODE_EXTENTS))) { + ext4_msg(sb, KERN_ERR, + "Online defrag not supported for non-extent files"); + return -EOPNOTSUPP; } - replaced_count = 0; - goto unlock_pages; -} - -/** - * mext_check_arguments - Check whether move extent can be done - * - * @orig_inode: original inode - * @donor_inode: donor inode - * @orig_start: logical start offset in block for orig - * @donor_start: logical start offset in block for donor - * @len: the number of blocks to be moved - * - * Check the arguments of ext4_move_extents() whether the files can be - * exchanged with each other. - * Return 0 on success, or a negative error value on failure. - */ -static int -mext_check_arguments(struct inode *orig_inode, - struct inode *donor_inode, __u64 orig_start, - __u64 donor_start, __u64 *len) -{ - ext4_lblk_t orig_blocks, donor_blocks; - unsigned int blkbits = orig_inode->i_blkbits; - unsigned int blocksize = 1 << blkbits; if (donor_inode->i_mode & (S_ISUID|S_ISGID)) { - ext4_debug("ext4 move extent: suid or sgid is set" - " to donor file [ino:orig %lu, donor %lu]\n", + ext4_debug("ext4 move extent: suid or sgid is set to donor file [ino:orig %lu, donor %lu]\n", orig_inode->i_ino, donor_inode->i_ino); return -EINVAL; } - if (IS_IMMUTABLE(donor_inode) || IS_APPEND(donor_inode)) + if (IS_IMMUTABLE(donor_inode) || IS_APPEND(donor_inode)) { + ext4_debug("ext4 move extent: donor should not be immutable or append file [ino:orig %lu, donor %lu]\n", + orig_inode->i_ino, donor_inode->i_ino); return -EPERM; + } - /* Ext4 move extent does not support swapfile */ + /* Ext4 move extent does not support swap files */ if (IS_SWAPFILE(orig_inode) || IS_SWAPFILE(donor_inode)) { - ext4_debug("ext4 move extent: The argument files should " - "not be swapfile [ino:orig %lu, donor %lu]\n", - orig_inode->i_ino, donor_inode->i_ino); - return -EINVAL; + ext4_debug("ext4 move extent: The argument files should not be swap files [ino:orig %lu, donor %lu]\n", + orig_inode->i_ino, donor_inode->i_ino); + return -ETXTBSY; } - /* Ext4 move extent supports only extent based file */ - if (!(ext4_test_inode_flag(orig_inode, EXT4_INODE_EXTENTS))) { - ext4_debug("ext4 move extent: orig file is not extents " - "based file [ino:orig %lu]\n", orig_inode->i_ino); - return -EOPNOTSUPP; - } else if (!(ext4_test_inode_flag(donor_inode, EXT4_INODE_EXTENTS))) { - ext4_debug("ext4 move extent: donor file is not extents " - "based file [ino:donor %lu]\n", donor_inode->i_ino); + if (ext4_is_quota_file(orig_inode) || ext4_is_quota_file(donor_inode)) { + ext4_debug("ext4 move extent: The argument files should not be quota files [ino:orig %lu, donor %lu]\n", + orig_inode->i_ino, donor_inode->i_ino); return -EOPNOTSUPP; } @@ -1130,72 +502,52 @@ mext_check_arguments(struct inode *orig_inode, return -EINVAL; } + return 0; +} + +/* + * Check the moving range of ext4_move_extents() whether the files can be + * exchanged with each other, and adjust the length to fit within the file + * size. Return 0 on success, or a negative error value on failure. + */ +static int mext_check_adjust_range(struct inode *orig_inode, + struct inode *donor_inode, __u64 orig_start, + __u64 donor_start, __u64 *len) +{ + __u64 orig_eof, donor_eof; + /* Start offset should be same */ - if (orig_start != donor_start) { - ext4_debug("ext4 move extent: orig and donor's start " - "offset are not same [ino:orig %lu, donor %lu]\n", - orig_inode->i_ino, donor_inode->i_ino); + if ((orig_start & ~(PAGE_MASK >> orig_inode->i_blkbits)) != + (donor_start & ~(PAGE_MASK >> orig_inode->i_blkbits))) { + ext4_debug("ext4 move extent: orig and donor's start offsets are not aligned [ino:orig %lu, donor %lu]\n", + orig_inode->i_ino, donor_inode->i_ino); return -EINVAL; } if ((orig_start >= EXT_MAX_BLOCKS) || + (donor_start >= EXT_MAX_BLOCKS) || (*len > EXT_MAX_BLOCKS) || + (donor_start + *len >= EXT_MAX_BLOCKS) || (orig_start + *len >= EXT_MAX_BLOCKS)) { - ext4_debug("ext4 move extent: Can't handle over [%u] blocks " - "[ino:orig %lu, donor %lu]\n", EXT_MAX_BLOCKS, - orig_inode->i_ino, donor_inode->i_ino); + ext4_debug("ext4 move extent: Can't handle over [%u] blocks [ino:orig %lu, donor %lu]\n", + EXT_MAX_BLOCKS, + orig_inode->i_ino, donor_inode->i_ino); return -EINVAL; } - if (orig_inode->i_size > donor_inode->i_size) { - donor_blocks = (donor_inode->i_size + blocksize - 1) >> blkbits; - /* TODO: eliminate this artificial restriction */ - if (orig_start >= donor_blocks) { - ext4_debug("ext4 move extent: orig start offset " - "[%llu] should be less than donor file blocks " - "[%u] [ino:orig %lu, donor %lu]\n", - orig_start, donor_blocks, - orig_inode->i_ino, donor_inode->i_ino); - return -EINVAL; - } - - /* TODO: eliminate this artificial restriction */ - if (orig_start + *len > donor_blocks) { - ext4_debug("ext4 move extent: End offset [%llu] should " - "be less than donor file blocks [%u]." - "So adjust length from %llu to %llu " - "[ino:orig %lu, donor %lu]\n", - orig_start + *len, donor_blocks, - *len, donor_blocks - orig_start, - orig_inode->i_ino, donor_inode->i_ino); - *len = donor_blocks - orig_start; - } - } else { - orig_blocks = (orig_inode->i_size + blocksize - 1) >> blkbits; - if (orig_start >= orig_blocks) { - ext4_debug("ext4 move extent: start offset [%llu] " - "should be less than original file blocks " - "[%u] [ino:orig %lu, donor %lu]\n", - orig_start, orig_blocks, - orig_inode->i_ino, donor_inode->i_ino); - return -EINVAL; - } - - if (orig_start + *len > orig_blocks) { - ext4_debug("ext4 move extent: Adjust length " - "from %llu to %llu. Because it should be " - "less than original file blocks " - "[ino:orig %lu, donor %lu]\n", - *len, orig_blocks - orig_start, - orig_inode->i_ino, donor_inode->i_ino); - *len = orig_blocks - orig_start; - } - } - + orig_eof = EXT4_B_TO_LBLK(orig_inode, i_size_read(orig_inode)); + donor_eof = EXT4_B_TO_LBLK(donor_inode, i_size_read(donor_inode)); + if (orig_eof <= orig_start) + *len = 0; + else if (orig_eof < orig_start + *len - 1) + *len = orig_eof - orig_start; + if (donor_eof <= donor_start) + *len = 0; + else if (donor_eof < donor_start + *len - 1) + *len = donor_eof - donor_start; if (!*len) { - ext4_debug("ext4 move extent: len should not be 0 " - "[ino:orig %lu, donor %lu]\n", orig_inode->i_ino, - donor_inode->i_ino); + ext4_debug("ext4 move extent: len should not be 0 [ino:orig %lu, donor %lu]\n", + orig_inode->i_ino, donor_inode->i_ino); return -EINVAL; } @@ -1203,339 +555,100 @@ mext_check_arguments(struct inode *orig_inode, } /** - * ext4_inode_double_lock - Lock i_mutex on both @inode1 and @inode2 - * - * @inode1: the inode structure - * @inode2: the inode structure - * - * Lock two inodes' i_mutex - */ -void -ext4_inode_double_lock(struct inode *inode1, struct inode *inode2) -{ - BUG_ON(inode1 == inode2); - if (inode1 < inode2) { - mutex_lock_nested(&inode1->i_mutex, I_MUTEX_PARENT); - mutex_lock_nested(&inode2->i_mutex, I_MUTEX_CHILD); - } else { - mutex_lock_nested(&inode2->i_mutex, I_MUTEX_PARENT); - mutex_lock_nested(&inode1->i_mutex, I_MUTEX_CHILD); - } -} - -/** - * ext4_inode_double_unlock - Release i_mutex on both @inode1 and @inode2 - * - * @inode1: the inode that is released first - * @inode2: the inode that is released second - * - */ - -void -ext4_inode_double_unlock(struct inode *inode1, struct inode *inode2) -{ - mutex_unlock(&inode1->i_mutex); - mutex_unlock(&inode2->i_mutex); -} - -/** * ext4_move_extents - Exchange the specified range of a file * * @o_filp: file structure of the original file * @d_filp: file structure of the donor file - * @orig_start: start offset in block for orig - * @donor_start: start offset in block for donor + * @orig_blk: start offset in block for orig + * @donor_blk: start offset in block for donor * @len: the number of blocks to be moved * @moved_len: moved block length * * This function returns 0 and moved block length is set in moved_len * if succeed, otherwise returns error value. - * - * Note: ext4_move_extents() proceeds the following order. - * 1:ext4_move_extents() calculates the last block number of moving extent - * function by the start block number (orig_start) and the number of blocks - * to be moved (len) specified as arguments. - * If the {orig, donor}_start points a hole, the extent's start offset - * pointed by ext_cur (current extent), holecheck_path, orig_path are set - * after hole behind. - * 2:Continue step 3 to step 5, until the holecheck_path points to last_extent - * or the ext_cur exceeds the block_end which is last logical block number. - * 3:To get the length of continues area, call mext_next_extent() - * specified with the ext_cur (initial value is holecheck_path) re-cursive, - * until find un-continuous extent, the start logical block number exceeds - * the block_end or the extent points to the last extent. - * 4:Exchange the original inode data with donor inode data - * from orig_page_offset to seq_end_page. - * The start indexes of data are specified as arguments. - * That of the original inode is orig_page_offset, - * and the donor inode is also orig_page_offset - * (To easily handle blocksize != pagesize case, the offset for the - * donor inode is block unit). - * 5:Update holecheck_path and orig_path to points a next proceeding extent, - * then returns to step 2. - * 6:Release holecheck_path, orig_path and set the len to moved_len - * which shows the number of moved blocks. - * The moved_len is useful for the command to calculate the file offset - * for starting next move extent ioctl. - * 7:Return 0 on success, or a negative error value on failure. */ -int -ext4_move_extents(struct file *o_filp, struct file *d_filp, - __u64 orig_start, __u64 donor_start, __u64 len, - __u64 *moved_len) +int ext4_move_extents(struct file *o_filp, struct file *d_filp, __u64 orig_blk, + __u64 donor_blk, __u64 len, __u64 *moved_len) { struct inode *orig_inode = file_inode(o_filp); struct inode *donor_inode = file_inode(d_filp); - struct ext4_ext_path *orig_path = NULL, *holecheck_path = NULL; - struct ext4_extent *ext_prev, *ext_cur, *ext_dummy; - ext4_lblk_t block_start = orig_start; - ext4_lblk_t block_end, seq_start, add_blocks, file_end, seq_blocks = 0; - ext4_lblk_t rest_blocks; - pgoff_t orig_page_offset = 0, seq_end_page; - int ret, depth, last_extent = 0; - int blocks_per_page = PAGE_CACHE_SIZE >> orig_inode->i_blkbits; - int data_offset_in_page; - int block_len_in_page; - int uninit; + struct mext_data mext; + struct super_block *sb = orig_inode->i_sb; + struct ext4_sb_info *sbi = EXT4_SB(sb); + int retries = 0; + u64 m_len; + int ret; - if (orig_inode->i_sb != donor_inode->i_sb) { - ext4_debug("ext4 move extent: The argument files " - "should be in same FS [ino:orig %lu, donor %lu]\n", - orig_inode->i_ino, donor_inode->i_ino); - return -EINVAL; - } + *moved_len = 0; - /* orig and donor should be different inodes */ - if (orig_inode == donor_inode) { - ext4_debug("ext4 move extent: The argument files should not " - "be same inode [ino:orig %lu, donor %lu]\n", - orig_inode->i_ino, donor_inode->i_ino); - return -EINVAL; - } - - /* Regular file check */ - if (!S_ISREG(orig_inode->i_mode) || !S_ISREG(donor_inode->i_mode)) { - ext4_debug("ext4 move extent: The argument files should be " - "regular file [ino:orig %lu, donor %lu]\n", - orig_inode->i_ino, donor_inode->i_ino); - return -EINVAL; - } - /* TODO: This is non obvious task to swap blocks for inodes with full - jornaling enabled */ - if (ext4_should_journal_data(orig_inode) || - ext4_should_journal_data(donor_inode)) { - return -EINVAL; - } /* Protect orig and donor inodes against a truncate */ - ext4_inode_double_lock(orig_inode, donor_inode); - - /* Wait for all existing dio workers */ - ext4_inode_block_unlocked_dio(orig_inode); - ext4_inode_block_unlocked_dio(donor_inode); - inode_dio_wait(orig_inode); - inode_dio_wait(donor_inode); + lock_two_nondirectories(orig_inode, donor_inode); - /* Protect extent tree against block allocations via delalloc */ - ext4_double_down_write_data_sem(orig_inode, donor_inode); - /* Check the filesystem environment whether move_extent can be done */ - ret = mext_check_arguments(orig_inode, donor_inode, orig_start, - donor_start, &len); + ret = mext_check_validity(orig_inode, donor_inode); if (ret) goto out; - file_end = (i_size_read(orig_inode) - 1) >> orig_inode->i_blkbits; - block_end = block_start + len - 1; - if (file_end < block_end) - len -= block_end - file_end; - - ret = get_ext_path(orig_inode, block_start, &orig_path); - if (ret) - goto out; + /* Wait for all existing dio workers */ + inode_dio_wait(orig_inode); + inode_dio_wait(donor_inode); - /* Get path structure to check the hole */ - ret = get_ext_path(orig_inode, block_start, &holecheck_path); + /* Check and adjust the specified move_extent range. */ + ret = mext_check_adjust_range(orig_inode, donor_inode, orig_blk, + donor_blk, &len); if (ret) goto out; - depth = ext_depth(orig_inode); - ext_cur = holecheck_path[depth].p_ext; + mext.orig_inode = orig_inode; + mext.donor_inode = donor_inode; + while (len) { + mext.orig_map.m_lblk = orig_blk; + mext.orig_map.m_len = len; + mext.orig_map.m_flags = 0; + mext.donor_lblk = donor_blk; - /* - * Get proper starting location of block replacement if block_start was - * within the hole. - */ - if (le32_to_cpu(ext_cur->ee_block) + - ext4_ext_get_actual_len(ext_cur) - 1 < block_start) { - /* - * The hole exists between extents or the tail of - * original file. - */ - last_extent = mext_next_extent(orig_inode, - holecheck_path, &ext_cur); - if (last_extent < 0) { - ret = last_extent; - goto out; - } - last_extent = mext_next_extent(orig_inode, orig_path, - &ext_dummy); - if (last_extent < 0) { - ret = last_extent; + ret = ext4_map_blocks(NULL, orig_inode, &mext.orig_map, 0); + if (ret < 0) goto out; - } - seq_start = le32_to_cpu(ext_cur->ee_block); - } else if (le32_to_cpu(ext_cur->ee_block) > block_start) - /* The hole exists at the beginning of original file. */ - seq_start = le32_to_cpu(ext_cur->ee_block); - else - seq_start = block_start; - - /* No blocks within the specified range. */ - if (le32_to_cpu(ext_cur->ee_block) > block_end) { - ext4_debug("ext4 move extent: The specified range of file " - "may be the hole\n"); - ret = -EINVAL; - goto out; - } - - /* Adjust start blocks */ - add_blocks = min(le32_to_cpu(ext_cur->ee_block) + - ext4_ext_get_actual_len(ext_cur), block_end + 1) - - max(le32_to_cpu(ext_cur->ee_block), block_start); - - while (!last_extent && le32_to_cpu(ext_cur->ee_block) <= block_end) { - seq_blocks += add_blocks; - - /* Adjust tail blocks */ - if (seq_start + seq_blocks - 1 > block_end) - seq_blocks = block_end - seq_start + 1; - ext_prev = ext_cur; - last_extent = mext_next_extent(orig_inode, holecheck_path, - &ext_cur); - if (last_extent < 0) { - ret = last_extent; - break; - } - add_blocks = ext4_ext_get_actual_len(ext_cur); - - /* - * Extend the length of contiguous block (seq_blocks) - * if extents are contiguous. - */ - if (ext4_can_extents_be_merged(orig_inode, - ext_prev, ext_cur) && - block_end >= le32_to_cpu(ext_cur->ee_block) && - !last_extent) - continue; - - /* Is original extent is uninitialized */ - uninit = ext4_ext_is_uninitialized(ext_prev); - - data_offset_in_page = seq_start % blocks_per_page; - - /* - * Calculate data blocks count that should be swapped - * at the first page. - */ - if (data_offset_in_page + seq_blocks > blocks_per_page) { - /* Swapped blocks are across pages */ - block_len_in_page = - blocks_per_page - data_offset_in_page; - } else { - /* Swapped blocks are in a page */ - block_len_in_page = seq_blocks; - } - - orig_page_offset = seq_start >> - (PAGE_CACHE_SHIFT - orig_inode->i_blkbits); - seq_end_page = (seq_start + seq_blocks - 1) >> - (PAGE_CACHE_SHIFT - orig_inode->i_blkbits); - seq_start = le32_to_cpu(ext_cur->ee_block); - rest_blocks = seq_blocks; - - /* - * Up semaphore to avoid following problems: - * a. transaction deadlock among ext4_journal_start, - * ->write_begin via pagefault, and jbd2_journal_commit - * b. racing with ->readpage, ->write_begin, and ext4_get_block - * in move_extent_per_page - */ - ext4_double_up_write_data_sem(orig_inode, donor_inode); - - while (orig_page_offset <= seq_end_page) { - - /* Swap original branches with new branches */ - block_len_in_page = move_extent_per_page( - o_filp, donor_inode, - orig_page_offset, - data_offset_in_page, - block_len_in_page, uninit, - &ret); - - /* Count how many blocks we have exchanged */ - *moved_len += block_len_in_page; - if (ret < 0) - break; - if (*moved_len > len) { - EXT4_ERROR_INODE(orig_inode, - "We replaced blocks too much! " - "sum of replaced: %llu requested: %llu", - *moved_len, len); - ret = -EIO; - break; + /* Skip moving if it is a hole or a delalloc extent. */ + if (mext.orig_map.m_flags & + (EXT4_MAP_MAPPED | EXT4_MAP_UNWRITTEN)) { + ret = mext_move_extent(&mext, &m_len); + *moved_len += m_len; + if (!ret) + goto next; + + /* Move failed or partially failed. */ + if (m_len) { + orig_blk += m_len; + donor_blk += m_len; + len -= m_len; } + if (ret == -ESTALE) + continue; + if (ret == -ENOSPC && + ext4_should_retry_alloc(sb, &retries)) + continue; + if (ret == -EBUSY && + sbi->s_journal && retries++ < 4 && + jbd2_journal_force_commit_nested(sbi->s_journal)) + continue; - orig_page_offset++; - data_offset_in_page = 0; - rest_blocks -= block_len_in_page; - if (rest_blocks > blocks_per_page) - block_len_in_page = blocks_per_page; - else - block_len_in_page = rest_blocks; + goto out; } - - ext4_double_down_write_data_sem(orig_inode, donor_inode); - if (ret < 0) - break; - - /* Decrease buffer counter */ - if (holecheck_path) - ext4_ext_drop_refs(holecheck_path); - ret = get_ext_path(orig_inode, seq_start, &holecheck_path); - if (ret) - break; - depth = holecheck_path->p_depth; - - /* Decrease buffer counter */ - if (orig_path) - ext4_ext_drop_refs(orig_path); - ret = get_ext_path(orig_inode, seq_start, &orig_path); - if (ret) - break; - - ext_cur = holecheck_path[depth].p_ext; - add_blocks = ext4_ext_get_actual_len(ext_cur); - seq_blocks = 0; - +next: + orig_blk += mext.orig_map.m_len; + donor_blk += mext.orig_map.m_len; + len -= mext.orig_map.m_len; + retries = 0; } + out: if (*moved_len) { ext4_discard_preallocations(orig_inode); ext4_discard_preallocations(donor_inode); } - if (orig_path) { - ext4_ext_drop_refs(orig_path); - kfree(orig_path); - } - if (holecheck_path) { - ext4_ext_drop_refs(holecheck_path); - kfree(holecheck_path); - } - ext4_double_up_write_data_sem(orig_inode, donor_inode); - ext4_inode_resume_unlocked_dio(orig_inode); - ext4_inode_resume_unlocked_dio(donor_inode); - ext4_inode_double_unlock(orig_inode, donor_inode); - + unlock_two_nondirectories(orig_inode, donor_inode); return ret; } |