diff options
Diffstat (limited to 'fs/ext4/move_extent.c')
| -rw-r--r-- | fs/ext4/move_extent.c | 1011 |
1 files changed, 598 insertions, 413 deletions
diff --git a/fs/ext4/move_extent.c b/fs/ext4/move_extent.c index bbf2dd9404d..2484c7ec6a7 100644 --- a/fs/ext4/move_extent.c +++ b/fs/ext4/move_extent.c @@ -15,18 +15,38 @@ #include <linux/fs.h> #include <linux/quotaops.h> +#include <linux/slab.h> #include "ext4_jbd2.h" -#include "ext4_extents.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, EXT4_EX_NOCACHE); + if (IS_ERR(path)) + ret = PTR_ERR(path); + else if (path[ext_depth(inode)].p_ext == NULL) + ret = -ENODATA; + else + *orig_path = path; -#define get_ext_path(path, inode, block, ret) \ - do { \ - path = ext4_ext_find_extent(inode, block, path); \ - if (IS_ERR(path)) { \ - ret = PTR_ERR(path); \ - path = NULL; \ - } \ - } while (0) + return ret; +} /** * copy_extent_status - Copy the extent's initialization status @@ -37,8 +57,8 @@ static void copy_extent_status(struct ext4_extent *src, struct ext4_extent *dest) { - if (ext4_ext_is_uninitialized(src)) - ext4_ext_mark_uninitialized(dest); + if (ext4_ext_is_unwritten(src)) + ext4_ext_mark_unwritten(dest); else dest->ee_len = cpu_to_le16(ext4_ext_get_actual_len(dest)); } @@ -56,16 +76,18 @@ copy_extent_status(struct ext4_extent *src, struct ext4_extent *dest) * ext4_ext_path structure refers to the last extent, or a negative error * value on failure. */ -static int +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; } @@ -76,7 +98,7 @@ mext_next_extent(struct inode *inode, struct ext4_ext_path *path, /* index block */ path[ppos].p_idx++; - path[ppos].p_block = idx_pblock(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 = @@ -91,7 +113,7 @@ mext_next_extent(struct inode *inode, struct ext4_ext_path *path, path[cur_ppos].p_idx = EXT_FIRST_INDEX(path[cur_ppos].p_hdr); path[cur_ppos].p_block = - idx_pblock(path[cur_ppos].p_idx); + 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, @@ -102,9 +124,18 @@ mext_next_extent(struct inode *inode, struct ext4_ext_path *path, ext_block_hdr(path[cur_ppos+1].p_bh); } + path[leaf_ppos].p_ext = *extent = NULL; + + 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; } } @@ -113,89 +144,35 @@ mext_next_extent(struct inode *inode, struct ext4_ext_path *path, } /** - * mext_double_down_read - Acquire two inodes' read semaphore + * ext4_double_down_write_data_sem - Acquire two inodes' write lock + * of i_data_sem * - * @orig_inode: original inode structure - * @donor_inode: donor inode structure - * Acquire read semaphore of the two inodes (orig and donor) by i_ino order. + * Acquire write lock of i_data_sem of the two inodes */ -static void -mext_double_down_read(struct inode *orig_inode, struct inode *donor_inode) +void +ext4_double_down_write_data_sem(struct inode *first, struct inode *second) { - struct inode *first = orig_inode, *second = donor_inode; - - BUG_ON(orig_inode == NULL || donor_inode == NULL); - - /* - * Use the inode number to provide the stable locking order instead - * of its address, because the C language doesn't guarantee you can - * compare pointers that don't come from the same array. - */ - if (donor_inode->i_ino < orig_inode->i_ino) { - first = donor_inode; - second = orig_inode; - } - - down_read(&EXT4_I(first)->i_data_sem); - down_read(&EXT4_I(second)->i_data_sem); -} - -/** - * mext_double_down_write - Acquire two inodes' write semaphore - * - * @orig_inode: original inode structure - * @donor_inode: donor inode structure - * Acquire write semaphore of the two inodes (orig and donor) by i_ino order. - */ -static void -mext_double_down_write(struct inode *orig_inode, struct inode *donor_inode) -{ - struct inode *first = orig_inode, *second = donor_inode; - - BUG_ON(orig_inode == NULL || donor_inode == NULL); + if (first < second) { + down_write(&EXT4_I(first)->i_data_sem); + down_write_nested(&EXT4_I(second)->i_data_sem, SINGLE_DEPTH_NESTING); + } else { + down_write(&EXT4_I(second)->i_data_sem); + down_write_nested(&EXT4_I(first)->i_data_sem, SINGLE_DEPTH_NESTING); - /* - * Use the inode number to provide the stable locking order instead - * of its address, because the C language doesn't guarantee you can - * compare pointers that don't come from the same array. - */ - if (donor_inode->i_ino < orig_inode->i_ino) { - first = donor_inode; - second = orig_inode; } - - down_write(&EXT4_I(first)->i_data_sem); - down_write(&EXT4_I(second)->i_data_sem); -} - -/** - * mext_double_up_read - Release two inodes' read semaphore - * - * @orig_inode: original inode structure to be released its lock first - * @donor_inode: donor inode structure to be released its lock second - * Release read semaphore of two inodes (orig and donor). - */ -static void -mext_double_up_read(struct inode *orig_inode, struct inode *donor_inode) -{ - BUG_ON(orig_inode == NULL || donor_inode == NULL); - - up_read(&EXT4_I(orig_inode)->i_data_sem); - up_read(&EXT4_I(donor_inode)->i_data_sem); } /** - * mext_double_up_write - Release two inodes' write semaphore + * ext4_double_up_write_data_sem - Release two inodes' write lock of i_data_sem * * @orig_inode: original inode structure to be released its lock first * @donor_inode: donor inode structure to be released its lock second - * Release write semaphore of two inodes (orig and donor). + * Release write lock of i_data_sem of two inodes (orig and donor). */ -static void -mext_double_up_write(struct inode *orig_inode, struct inode *donor_inode) +void +ext4_double_up_write_data_sem(struct inode *orig_inode, + struct inode *donor_inode) { - BUG_ON(orig_inode == NULL || donor_inode == NULL); - up_write(&EXT4_I(orig_inode)->i_data_sem); up_write(&EXT4_I(donor_inode)->i_data_sem); } @@ -242,10 +219,11 @@ mext_insert_across_blocks(handle_t *handle, struct inode *orig_inode, */ o_end->ee_block = end_ext->ee_block; o_end->ee_len = end_ext->ee_len; - ext4_ext_store_pblock(o_end, ext_pblock(end_ext)); + ext4_ext_store_pblock(o_end, ext4_ext_pblock(end_ext)); } 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 && @@ -256,6 +234,7 @@ mext_insert_across_blocks(handle_t *handle, struct inode *orig_inode, * 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 && @@ -267,7 +246,7 @@ mext_insert_across_blocks(handle_t *handle, struct inode *orig_inode, */ o_end->ee_block = end_ext->ee_block; o_end->ee_len = end_ext->ee_len; - ext4_ext_store_pblock(o_end, ext_pblock(end_ext)); + ext4_ext_store_pblock(o_end, ext4_ext_pblock(end_ext)); /* * Set 0 to the extent block if new_ext was @@ -283,23 +262,23 @@ mext_insert_across_blocks(handle_t *handle, struct inode *orig_inode, } if (new_flag) { - get_ext_path(orig_path, orig_inode, eblock, err); - if (orig_path == NULL) + 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)) + orig_path, new_ext, 0)) goto out; } if (end_flag) { - get_ext_path(orig_path, orig_inode, - le32_to_cpu(end_ext->ee_block) - 1, err); - if (orig_path == NULL) + 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)) + orig_path, end_ext, 0)) goto out; } out: @@ -352,7 +331,7 @@ mext_insert_inside_block(struct ext4_extent *o_start, /* Insert new entry */ if (new_ext->ee_len) { o_start[i] = *new_ext; - ext4_ext_store_pblock(&o_start[i++], ext_pblock(new_ext)); + ext4_ext_store_pblock(&o_start[i++], ext4_ext_pblock(new_ext)); } /* Insert end entry */ @@ -412,6 +391,7 @@ mext_insert_extents(handle_t *handle, struct inode *orig_inode, if (depth) { /* Register to journal */ + BUFFER_TRACE(orig_path->p_bh, "get_write_access"); ret = ext4_journal_get_write_access(handle, orig_path->p_bh); if (ret) return ret; @@ -430,18 +410,7 @@ mext_insert_extents(handle_t *handle, struct inode *orig_inode, mext_insert_inside_block(o_start, o_end, start_ext, new_ext, end_ext, eh, range_to_move); - if (depth) { - ret = ext4_handle_dirty_metadata(handle, orig_inode, - orig_path->p_bh); - if (ret) - return ret; - } else { - ret = ext4_mark_inode_dirty(handle, orig_inode); - if (ret < 0) - return ret; - } - - return 0; + return ext4_ext_dirty(handle, orig_inode, orig_path); } /** @@ -469,21 +438,20 @@ mext_leaf_block(handle_t *handle, struct inode *orig_inode, 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; - ext4_fsblk_t new_phys_end; int oext_alen, new_ext_alen, end_ext_alen; int depth = ext_depth(orig_inode); 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, ext_pblock(dext)); + 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; - new_phys_end = ext_pblock(&new_ext) + new_ext_alen - 1; /* * Case: original extent is first @@ -496,6 +464,7 @@ mext_leaf_block(handle_t *handle, struct inode *orig_inode, 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; @@ -509,6 +478,7 @@ mext_leaf_block(handle_t *handle, struct inode *orig_inode, 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; } @@ -519,7 +489,15 @@ mext_leaf_block(handle_t *handle, struct inode *orig_inode, * oext |-----------| * new_ext |-------| */ - BUG_ON(le32_to_cpu(oext->ee_block) + oext_alen - 1 < new_ext_end); + 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; + } /* * Case: new_ext is smaller than original extent @@ -535,7 +513,7 @@ mext_leaf_block(handle_t *handle, struct inode *orig_inode, copy_extent_status(oext, &end_ext); end_ext_alen = ext4_ext_get_actual_len(&end_ext); ext4_ext_store_pblock(&end_ext, - (ext_pblock(o_end) + oext_alen - end_ext_alen)); + (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); @@ -543,6 +521,7 @@ mext_leaf_block(handle_t *handle, struct inode *orig_inode, ret = mext_insert_extents(handle, orig_inode, orig_path, o_start, o_end, &start_ext, &new_ext, &end_ext); +out: return ret; } @@ -553,9 +532,11 @@ mext_leaf_block(handle_t *handle, struct inode *orig_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 maximun length of extents + * @max_count: the maximum length of extents + * + * Return 0 on success, or a negative error value on failure. */ -static void +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, @@ -564,22 +545,34 @@ mext_calc_swap_extents(struct ext4_extent *tmp_dext, 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, ext_pblock(tmp_dext) + diff); - tmp_dext->ee_block = - cpu_to_le32(le32_to_cpu(tmp_dext->ee_block) + diff); - tmp_dext->ee_len = cpu_to_le16(le16_to_cpu(tmp_dext->ee_len) - diff); + 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, ext_pblock(tmp_oext) + orig_diff); + ext4_ext_store_pblock(tmp_oext, ext4_ext_pblock(tmp_oext) + orig_diff); /* Adjust extent length if donor extent is larger than orig */ if (ext4_ext_get_actual_len(tmp_dext) > @@ -591,6 +584,46 @@ mext_calc_swap_extents(struct ext4_extent *tmp_dext, copy_extent_status(&oext_old, tmp_dext); copy_extent_status(&dext_old, tmp_oext); + + 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 + * @unwritten: extents expected to be unwritten + * @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 unwritten, 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 (unwritten != ext4_ext_is_unwritten(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; } /** @@ -601,6 +634,7 @@ mext_calc_swap_extents(struct ext4_extent *tmp_dext, * @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: @@ -611,33 +645,38 @@ mext_calc_swap_extents(struct ext4_extent *tmp_dext, * 3. Change the block information of donor inode to point at the saved * original inode blocks in the dummy extents. * - * Return 0 on success, or a negative error value on failure. + * Return replaced block count. */ static int mext_replace_branches(handle_t *handle, struct inode *orig_inode, struct inode *donor_inode, ext4_lblk_t from, - ext4_lblk_t count) + ext4_lblk_t count, int *err) { 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 err = 0; int depth; int replaced_count = 0; int dext_alen; - mext_double_down_write(orig_inode, donor_inode); + *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" */ - get_ext_path(orig_path, orig_inode, orig_off, err); - if (orig_path == NULL) + *err = get_ext_path(orig_inode, orig_off, &orig_path); + if (*err) goto out; /* Get the donor extent for the head */ - get_ext_path(donor_path, donor_inode, donor_off, err); - if (donor_path == NULL) + *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; @@ -645,26 +684,44 @@ mext_replace_branches(handle_t *handle, struct inode *orig_inode, depth = ext_depth(donor_inode); dext = donor_path[depth].p_ext; + if (unlikely(!dext)) + goto missing_donor_extent; tmp_dext = *dext; - mext_calc_swap_extents(&tmp_dext, &tmp_oext, orig_off, + *err = mext_calc_swap_extents(&tmp_dext, &tmp_oext, orig_off, donor_off, count); + if (*err) + goto out; /* Loop for the donor extents */ while (1) { /* The extent for donor must be found. */ - BUG_ON(!dext || donor_off != le32_to_cpu(tmp_dext.ee_block)); + 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, + *err = mext_leaf_block(handle, orig_inode, orig_path, &tmp_dext, &orig_off); - if (err < 0) + if (*err) goto out; /* Set orig extent to donor extent */ - err = mext_leaf_block(handle, donor_inode, + *err = mext_leaf_block(handle, donor_inode, donor_path, &tmp_oext, &donor_off); - if (err < 0) + if (*err) goto out; dext_alen = ext4_ext_get_actual_len(&tmp_dext); @@ -672,42 +729,33 @@ mext_replace_branches(handle_t *handle, struct inode *orig_inode, donor_off += dext_alen; orig_off += dext_alen; + BUG_ON(replaced_count > count); /* Already moved the expected blocks */ if (replaced_count >= count) break; if (orig_path) ext4_ext_drop_refs(orig_path); - get_ext_path(orig_path, orig_inode, orig_off, err); - if (orig_path == NULL) + *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; - if (le32_to_cpu(oext->ee_block) + - ext4_ext_get_actual_len(oext) <= orig_off) { - err = 0; - goto out; - } tmp_oext = *oext; if (donor_path) ext4_ext_drop_refs(donor_path); - get_ext_path(donor_path, donor_inode, - donor_off, err); - if (donor_path == NULL) + *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; - if (le32_to_cpu(dext->ee_block) + - ext4_ext_get_actual_len(dext) <= donor_off) { - err = 0; - goto out; - } tmp_dext = *dext; - mext_calc_swap_extents(&tmp_dext, &tmp_oext, orig_off, - donor_off, - count - replaced_count); + *err = mext_calc_swap_extents(&tmp_dext, &tmp_oext, orig_off, + donor_off, count - replaced_count); + if (*err) + goto out; } out: @@ -720,8 +768,123 @@ out: kfree(donor_path); } - mext_double_up_write(orig_inode, donor_inode); - return err; + 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; + + 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; + } + + page[0] = grab_cache_page_write_begin(mapping[0], index, fl); + if (!page[0]) + return -ENOMEM; + + 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; + } + /* + * 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 + */ + 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; + } + return 0; +} + +/* Force page buffers uptodate w/o dropping page's lock */ +static int +mext_page_mkuptodate(struct page *page, unsigned from, unsigned to) +{ + 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)); + + if (PageUptodate(page)) + return 0; + + blocksize = 1 << inode->i_blkbits; + if (!page_has_buffers(page)) + create_empty_buffers(page, blocksize, 0); + + 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); + set_buffer_uptodate(bh); + continue; + } + } + BUG_ON(nr >= MAX_BUF_PER_PAGE); + arr[nr++] = bh; + } + /* 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; + } + } +out: + if (!partial) + SetPageUptodate(page); + return 0; } /** @@ -732,42 +895,42 @@ out: * @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 + * @unwritten: orig extent is unwritten 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 0 - * on success, or a negative error value on failure. + * Finally, write out the saved data in new original inode blocks. Return + * replaced block count. */ static int -move_extent_par_page(struct file *o_filp, struct inode *donor_inode, +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 block_len_in_page, int unwritten, int *err) { - struct inode *orig_inode = o_filp->f_dentry->d_inode; - struct address_space *mapping = orig_inode->i_mapping; - struct buffer_head *bh; - struct page *page = NULL; - const struct address_space_operations *a_ops = mapping->a_ops; + struct inode *orig_inode = file_inode(o_filp); + struct page *pagep[2] = {NULL, NULL}; handle_t *handle; ext4_lblk_t orig_blk_offset; - long long offs = orig_page_offset << PAGE_CACHE_SHIFT; unsigned long blocksize = orig_inode->i_sb->s_blocksize; unsigned int w_flags = 0; - unsigned int tmp_data_len, data_len; - void *fsdata; - int ret, i, jblocks; + 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; /* * 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, jblocks); + handle = ext4_journal_start(orig_inode, EXT4_HT_MOVE_EXTENTS, jblocks); if (IS_ERR(handle)) { - ret = PTR_ERR(handle); - return ret; + *err = PTR_ERR(handle); + return 0; } if (segment_eq(get_fs(), KERNEL_DS)) @@ -776,117 +939,149 @@ move_extent_par_page(struct file *o_filp, struct inode *donor_inode, orig_blk_offset = orig_page_offset * blocks_per_page + data_offset_in_page; - /* - * If orig extent is uninitialized one, - * it's not necessary force the page into memory - * and then force it to be written out again. - * Just swap data blocks between orig and donor. - */ - if (uninit) { - ret = mext_replace_branches(handle, orig_inode, - donor_inode, orig_blk_offset, - block_len_in_page); - - /* Clear the inode cache not to refer to the old data */ - ext4_ext_invalidate_cache(orig_inode); - ext4_ext_invalidate_cache(donor_inode); - goto out2; - } - - offs = (long long)orig_blk_offset << orig_inode->i_blkbits; - - /* Calculate data_len */ + /* 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_len = orig_inode->i_size & (blocksize - 1); + tmp_data_size = orig_inode->i_size & (blocksize - 1); /* - * If data_len equal zero, it shows data_len is multiples of + * If data_size equal zero, it shows data_size is multiples of * blocksize. So we set appropriate value. */ - if (tmp_data_len == 0) - tmp_data_len = blocksize; + if (tmp_data_size == 0) + tmp_data_size = blocksize; - data_len = tmp_data_len + + data_size = tmp_data_size + ((block_len_in_page - 1) << orig_inode->i_blkbits); - } else { - data_len = block_len_in_page << orig_inode->i_blkbits; - } - - ret = a_ops->write_begin(o_filp, mapping, offs, data_len, w_flags, - &page, &fsdata); - if (unlikely(ret < 0)) - goto out; + } else + data_size = block_len_in_page << orig_inode->i_blkbits; - if (!PageUptodate(page)) { - mapping->a_ops->readpage(o_filp, page); - lock_page(page); - } + replaced_size = data_size; + *err = mext_page_double_lock(orig_inode, donor_inode, orig_page_offset, + pagep); + if (unlikely(*err < 0)) + goto stop_journal; /* - * try_to_release_page() doesn't call releasepage in writeback mode. - * We should care about the order of writing to the same file - * by multiple move extent processes. - * It needs to call wait_on_page_writeback() to wait for the - * writeback of the page. + * If orig extent was unwritten 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. */ - if (PageWriteback(page)) - wait_on_page_writeback(page); - - /* Release old bh and drop refs */ - try_to_release_page(page, 0); - - ret = mext_replace_branches(handle, orig_inode, donor_inode, - orig_blk_offset, block_len_in_page); - if (ret < 0) - goto out; - - /* Clear the inode cache not to refer to the old data */ - ext4_ext_invalidate_cache(orig_inode); - ext4_ext_invalidate_cache(donor_inode); - - if (!page_has_buffers(page)) - create_empty_buffers(page, 1 << orig_inode->i_blkbits, 0); - - bh = page_buffers(page); - for (i = 0; i < data_offset_in_page; i++) - bh = bh->b_this_page; - - for (i = 0; i < block_len_in_page; i++) { - ret = ext4_get_block(orig_inode, - (sector_t)(orig_blk_offset + i), bh, 0); - if (ret < 0) - goto out; - - if (bh->b_this_page != NULL) - bh = bh->b_this_page; + if (unwritten) { + 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 */ + unwritten = mext_check_coverage(orig_inode, orig_blk_offset, + block_len_in_page, 1, err); + if (*err) + goto drop_data_sem; + + unwritten &= mext_check_coverage(donor_inode, orig_blk_offset, + block_len_in_page, 1, err); + if (*err) + goto drop_data_sem; + + if (!unwritten) { + 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; } - ret = a_ops->write_end(o_filp, mapping, offs, data_len, data_len, - page, fsdata); - page = NULL; - -out: - if (unlikely(page)) { - if (PageLocked(page)) - unlock_page(page); - page_cache_release(page); + 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; } -out2: + /* 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); - - return ret < 0 ? ret : 0; + /* 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; + } + replaced_count = 0; + goto unlock_pages; } /** - * mext_check_argumants - Check whether move extent can be done + * 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 - * @moved_len: moved block length * * Check the arguments of ext4_move_extents() whether the files can be * exchanged with each other. @@ -894,17 +1089,23 @@ out2: */ static int mext_check_arguments(struct inode *orig_inode, - struct inode *donor_inode, __u64 orig_start, - __u64 donor_start, __u64 *len, __u64 moved_len) + struct inode *donor_inode, __u64 orig_start, + __u64 donor_start, __u64 *len) { - /* 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); + 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", + orig_inode->i_ino, donor_inode->i_ino); return -EINVAL; } + if (IS_IMMUTABLE(donor_inode) || IS_APPEND(donor_inode)) + return -EPERM; + /* Ext4 move extent does not support swapfile */ if (IS_SWAPFILE(orig_inode) || IS_SWAPFILE(donor_inode)) { ext4_debug("ext4 move extent: The argument files should " @@ -913,28 +1114,12 @@ mext_check_arguments(struct inode *orig_inode, return -EINVAL; } - /* Files should be in the same ext4 FS */ - 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; - } - - /* orig and donor should be different file */ - if (orig_inode->i_ino == donor_inode->i_ino) { - ext4_debug("ext4 move extent: The argument files should not " - "be same file [ino:orig %lu, donor %lu]\n", - orig_inode->i_ino, donor_inode->i_ino); - return -EINVAL; - } - /* Ext4 move extent supports only extent based file */ - if (!(EXT4_I(orig_inode)->i_flags & EXT4_EXTENTS_FL)) { + 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_I(donor_inode)->i_flags & EXT4_EXTENTS_FL)) { + } 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); return -EOPNOTSUPP; @@ -953,66 +1138,62 @@ mext_check_arguments(struct inode *orig_inode, return -EINVAL; } - if (moved_len) { - ext4_debug("ext4 move extent: moved_len should be 0 " - "[ino:orig %lu, donor %lu]\n", orig_inode->i_ino, - donor_inode->i_ino); - return -EINVAL; - } - - if ((orig_start > MAX_DEFRAG_SIZE) || - (donor_start > MAX_DEFRAG_SIZE) || - (*len > MAX_DEFRAG_SIZE) || - (orig_start + *len > MAX_DEFRAG_SIZE)) { - ext4_debug("ext4 move extent: Can't handle over [%lu] blocks " - "[ino:orig %lu, donor %lu]\n", MAX_DEFRAG_SIZE, + if ((orig_start >= EXT_MAX_BLOCKS) || + (*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); return -EINVAL; } if (orig_inode->i_size > donor_inode->i_size) { - if (orig_start >= 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 size " - "[%lld] [ino:orig %lu, donor_inode %lu]\n", - orig_start, donor_inode->i_size, + "[%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; } - if (orig_start + *len > donor_inode->i_size) { + /* 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 size [%lld]." - "So adjust length from %llu to %lld " + "be less than donor file blocks [%u]." + "So adjust length from %llu to %llu " "[ino:orig %lu, donor %lu]\n", - orig_start + *len, donor_inode->i_size, - *len, donor_inode->i_size - orig_start, + orig_start + *len, donor_blocks, + *len, donor_blocks - orig_start, orig_inode->i_ino, donor_inode->i_ino); - *len = donor_inode->i_size - orig_start; + *len = donor_blocks - orig_start; } } else { - if (orig_start >= orig_inode->i_size) { + 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 size " - "[%lld] [inode:orig %lu, donor %lu]\n", - orig_start, orig_inode->i_size, + "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_inode->i_size) { + if (orig_start + *len > orig_blocks) { ext4_debug("ext4 move extent: Adjust length " - "from %llu to %lld. Because it should be " - "less than original file size " + "from %llu to %llu. Because it should be " + "less than original file blocks " "[ino:orig %lu, donor %lu]\n", - *len, orig_inode->i_size - orig_start, + *len, orig_blocks - orig_start, orig_inode->i_ino, donor_inode->i_ino); - *len = orig_inode->i_size - orig_start; + *len = orig_blocks - orig_start; } } if (!*len) { - ext4_debug("ext4 move extent: len shoudld not be 0 " + 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; @@ -1022,54 +1203,6 @@ mext_check_arguments(struct inode *orig_inode, } /** - * mext_inode_double_lock - Lock i_mutex on both @inode1 and @inode2 - * - * @inode1: the inode structure - * @inode2: the inode structure - * - * Lock two inodes' i_mutex by i_ino order. This function is moved from - * fs/inode.c. - */ -static void -mext_inode_double_lock(struct inode *inode1, struct inode *inode2) -{ - if (inode1 == NULL || inode2 == NULL || inode1 == inode2) { - if (inode1) - mutex_lock(&inode1->i_mutex); - else if (inode2) - mutex_lock(&inode2->i_mutex); - return; - } - - if (inode1->i_ino < inode2->i_ino) { - 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); - } -} - -/** - * mext_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 - * - * This function is moved from fs/inode.c. - */ - -static void -mext_inode_double_unlock(struct inode *inode1, struct inode *inode2) -{ - if (inode1) - mutex_unlock(&inode1->i_mutex); - - if (inode2 && inode2 != inode1) - mutex_unlock(&inode2->i_mutex); -} - -/** * ext4_move_extents - Exchange the specified range of a file * * @o_filp: file structure of the original file @@ -1115,8 +1248,8 @@ ext4_move_extents(struct file *o_filp, struct file *d_filp, __u64 orig_start, __u64 donor_start, __u64 len, __u64 *moved_len) { - struct inode *orig_inode = o_filp->f_dentry->d_inode; - struct inode *donor_inode = d_filp->f_dentry->d_inode; + 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; @@ -1127,46 +1260,80 @@ ext4_move_extents(struct file *o_filp, struct file *d_filp, int blocks_per_page = PAGE_CACHE_SIZE >> orig_inode->i_blkbits; int data_offset_in_page; int block_len_in_page; - int uninit; + int unwritten; - /* protect orig and donor against a truncate */ - mext_inode_double_lock(orig_inode, donor_inode); + 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; + } - mext_double_down_read(orig_inode, donor_inode); + /* 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 */ + lock_two_nondirectories(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); + + /* 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, *moved_len); - mext_double_up_read(orig_inode, donor_inode); + donor_start, &len); if (ret) - goto out2; + 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; - get_ext_path(orig_path, orig_inode, block_start, ret); - if (orig_path == NULL) - goto out2; + ret = get_ext_path(orig_inode, block_start, &orig_path); + if (ret) + goto out; /* Get path structure to check the hole */ - get_ext_path(holecheck_path, orig_inode, block_start, ret); - if (holecheck_path == NULL) + ret = get_ext_path(orig_inode, block_start, &holecheck_path); + if (ret) goto out; depth = ext_depth(orig_inode); ext_cur = holecheck_path[depth].p_ext; - if (ext_cur == NULL) { - ret = -EINVAL; - goto out; - } /* - * Get proper extent whose ee_block is beyond block_start - * if block_start was within the hole. + * 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) { @@ -1179,8 +1346,12 @@ ext4_move_extents(struct file *o_filp, struct file *d_filp, ret = last_extent; goto out; } - } - seq_start = block_start; + 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) { @@ -1221,8 +1392,8 @@ ext4_move_extents(struct file *o_filp, struct file *d_filp, !last_extent) continue; - /* Is original extent is uninitialized */ - uninit = ext4_ext_is_uninitialized(ext_prev); + /* Is original extent is unwritten */ + unwritten = ext4_ext_is_unwritten(ext_prev); data_offset_in_page = seq_start % blocks_per_page; @@ -1246,29 +1417,39 @@ ext4_move_extents(struct file *o_filp, struct file *d_filp, seq_start = le32_to_cpu(ext_cur->ee_block); rest_blocks = seq_blocks; - /* Discard preallocations of two inodes */ - down_write(&EXT4_I(orig_inode)->i_data_sem); - ext4_discard_preallocations(orig_inode); - up_write(&EXT4_I(orig_inode)->i_data_sem); - - down_write(&EXT4_I(donor_inode)->i_data_sem); - ext4_discard_preallocations(donor_inode); - up_write(&EXT4_I(donor_inode)->i_data_sem); + /* + * 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 */ - ret = move_extent_par_page(o_filp, donor_inode, + block_len_in_page = move_extent_per_page( + o_filp, donor_inode, orig_page_offset, data_offset_in_page, - block_len_in_page, uninit); - if (ret < 0) - goto out; - orig_page_offset++; + block_len_in_page, + unwritten, &ret); + /* Count how many blocks we have exchanged */ *moved_len += block_len_in_page; - BUG_ON(*moved_len > len); + 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; + } + orig_page_offset++; data_offset_in_page = 0; rest_blocks -= block_len_in_page; if (rest_blocks > blocks_per_page) @@ -1277,20 +1458,23 @@ ext4_move_extents(struct file *o_filp, struct file *d_filp, block_len_in_page = rest_blocks; } + 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); - get_ext_path(holecheck_path, orig_inode, - seq_start, ret); - if (holecheck_path == NULL) + 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); - get_ext_path(orig_path, orig_inode, seq_start, ret); - if (orig_path == NULL) + ret = get_ext_path(orig_inode, seq_start, &orig_path); + if (ret) break; ext_cur = holecheck_path[depth].p_ext; @@ -1299,6 +1483,11 @@ ext4_move_extents(struct file *o_filp, struct file *d_filp, } 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); @@ -1307,14 +1496,10 @@ out: ext4_ext_drop_refs(holecheck_path); kfree(holecheck_path); } -out2: - mext_inode_double_unlock(orig_inode, donor_inode); - - if (ret) - return ret; - - /* All of the specified blocks must be exchanged in succeed */ - BUG_ON(*moved_len != len); + ext4_double_up_write_data_sem(orig_inode, donor_inode); + ext4_inode_resume_unlocked_dio(orig_inode); + ext4_inode_resume_unlocked_dio(donor_inode); + unlock_two_nondirectories(orig_inode, donor_inode); - return 0; + return ret; } |