diff options
Diffstat (limited to 'fs/ext4/mballoc.c')
| -rw-r--r-- | fs/ext4/mballoc.c | 691 |
1 files changed, 435 insertions, 256 deletions
diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c index 5b2ae37a8b80..78259bddbc4d 100644 --- a/fs/ext4/mballoc.c +++ b/fs/ext4/mballoc.c @@ -1168,10 +1168,8 @@ static int ext4_mb_init_cache(struct page *page, char *incore, gfp_t gfp) if (groups_per_page > 1) { i = sizeof(struct buffer_head *) * groups_per_page; bh = kzalloc(i, gfp); - if (bh == NULL) { - err = -ENOMEM; - goto out; - } + if (bh == NULL) + return -ENOMEM; } else bh = &bhs; @@ -1489,7 +1487,13 @@ ext4_mb_load_buddy_gfp(struct super_block *sb, ext4_group_t group, put_page(page); page = find_or_create_page(inode->i_mapping, pnum, gfp); if (page) { - BUG_ON(page->mapping != inode->i_mapping); + if (WARN_RATELIMIT(page->mapping != inode->i_mapping, + "ext4: bitmap's paging->mapping != inode->i_mapping\n")) { + /* should never happen */ + unlock_page(page); + ret = -EINVAL; + goto err; + } if (!PageUptodate(page)) { ret = ext4_mb_init_cache(page, NULL, gfp); if (ret) { @@ -1525,7 +1529,13 @@ ext4_mb_load_buddy_gfp(struct super_block *sb, ext4_group_t group, put_page(page); page = find_or_create_page(inode->i_mapping, pnum, gfp); if (page) { - BUG_ON(page->mapping != inode->i_mapping); + if (WARN_RATELIMIT(page->mapping != inode->i_mapping, + "ext4: buddy bitmap's page->mapping != inode->i_mapping\n")) { + /* should never happen */ + unlock_page(page); + ret = -EINVAL; + goto err; + } if (!PageUptodate(page)) { ret = ext4_mb_init_cache(page, e4b->bd_bitmap, gfp); @@ -1557,8 +1567,7 @@ err: put_page(page); if (e4b->bd_bitmap_page) put_page(e4b->bd_bitmap_page); - if (e4b->bd_buddy_page) - put_page(e4b->bd_buddy_page); + e4b->bd_buddy = NULL; e4b->bd_bitmap = NULL; return ret; @@ -1721,7 +1730,8 @@ static void mb_buddy_mark_free(struct ext4_buddy *e4b, int first, int last) break; order++; - if (first == last || !(buddy2 = mb_find_buddy(e4b, order, &max))) { + buddy2 = mb_find_buddy(e4b, order, &max); + if (!buddy2) { mb_clear_bits(buddy, first, last - first + 1); e4b->bd_info->bb_counters[order - 1] += last - first + 1; break; @@ -2021,8 +2031,6 @@ static void ext4_mb_check_limits(struct ext4_allocation_context *ac, struct ext4_sb_info *sbi = EXT4_SB(ac->ac_sb); struct ext4_free_extent *bex = &ac->ac_b_ex; struct ext4_free_extent *gex = &ac->ac_g_ex; - struct ext4_free_extent ex; - int max; if (ac->ac_status == AC_STATUS_FOUND) return; @@ -2041,17 +2049,8 @@ static void ext4_mb_check_limits(struct ext4_allocation_context *ac, if (bex->fe_len < gex->fe_len) return; - if ((finish_group || ac->ac_found > sbi->s_mb_min_to_scan) - && bex->fe_group == e4b->bd_group) { - /* recheck chunk's availability - we don't know - * when it was found (within this lock-unlock - * period or not) */ - max = mb_find_extent(e4b, bex->fe_start, gex->fe_len, &ex); - if (max >= gex->fe_len) { - ext4_mb_use_best_found(ac, e4b); - return; - } - } + if (finish_group) + ext4_mb_use_best_found(ac, e4b); } /* @@ -2124,7 +2123,7 @@ static void ext4_mb_measure_extent(struct ext4_allocation_context *ac, } static noinline_for_stack -int ext4_mb_try_best_found(struct ext4_allocation_context *ac, +void ext4_mb_try_best_found(struct ext4_allocation_context *ac, struct ext4_buddy *e4b) { struct ext4_free_extent ex = ac->ac_b_ex; @@ -2135,7 +2134,7 @@ int ext4_mb_try_best_found(struct ext4_allocation_context *ac, BUG_ON(ex.fe_len <= 0); err = ext4_mb_load_buddy(ac->ac_sb, group, e4b); if (err) - return err; + return; ext4_lock_group(ac->ac_sb, group); max = mb_find_extent(e4b, ex.fe_start, ex.fe_len, &ex); @@ -2147,8 +2146,6 @@ int ext4_mb_try_best_found(struct ext4_allocation_context *ac, ext4_unlock_group(ac->ac_sb, group); ext4_mb_unload_buddy(e4b); - - return 0; } static noinline_for_stack @@ -2162,7 +2159,7 @@ int ext4_mb_find_by_goal(struct ext4_allocation_context *ac, struct ext4_group_info *grp = ext4_get_group_info(ac->ac_sb, group); struct ext4_free_extent ex; - if (!(ac->ac_flags & EXT4_MB_HINT_TRY_GOAL)) + if (!(ac->ac_flags & (EXT4_MB_HINT_TRY_GOAL | EXT4_MB_HINT_GOAL_ONLY))) return 0; if (grp->bb_free == 0) return 0; @@ -2236,7 +2233,9 @@ void ext4_mb_simple_scan_group(struct ext4_allocation_context *ac, continue; buddy = mb_find_buddy(e4b, i, &max); - BUG_ON(buddy == NULL); + if (WARN_RATELIMIT(buddy == NULL, + "ext4: mb_simple_scan_group: mb_find_buddy failed, (%d)\n", i)) + continue; k = mb_find_next_zero_bit(buddy, max, 0); if (k >= max) { @@ -2569,14 +2568,14 @@ ext4_group_t ext4_mb_prefetch(struct super_block *sb, ext4_group_t group, void ext4_mb_prefetch_fini(struct super_block *sb, ext4_group_t group, unsigned int nr) { - while (nr-- > 0) { - struct ext4_group_desc *gdp = ext4_get_group_desc(sb, group, - NULL); - struct ext4_group_info *grp = ext4_get_group_info(sb, group); + struct ext4_group_desc *gdp; + struct ext4_group_info *grp; + while (nr-- > 0) { if (!group) group = ext4_get_groups_count(sb); group--; + gdp = ext4_get_group_desc(sb, group, NULL); grp = ext4_get_group_info(sb, group); if (EXT4_MB_GRP_NEED_INIT(grp) && @@ -3084,7 +3083,7 @@ int ext4_mb_add_groupinfo(struct super_block *sb, ext4_group_t group, if (meta_group_info == NULL) { ext4_msg(sb, KERN_ERR, "can't allocate mem " "for a buddy group"); - goto exit_meta_group_info; + return -ENOMEM; } rcu_read_lock(); rcu_dereference(sbi->s_group_info)[idx] = meta_group_info; @@ -3138,7 +3137,6 @@ exit_group_info: group_info[idx] = NULL; rcu_read_unlock(); } -exit_meta_group_info: return -ENOMEM; } /* ext4_mb_add_groupinfo */ @@ -3419,7 +3417,6 @@ int ext4_mb_init(struct super_block *sb) sbi->s_mb_stats = MB_DEFAULT_STATS; sbi->s_mb_stream_request = MB_DEFAULT_STREAM_THRESHOLD; sbi->s_mb_order2_reqs = MB_DEFAULT_ORDER2_REQS; - sbi->s_mb_max_inode_prealloc = MB_DEFAULT_MAX_INODE_PREALLOC; /* * The default group preallocation is 512, which for 4k block * sizes translates to 2 megabytes. However for bigalloc file @@ -3606,7 +3603,7 @@ static void ext4_free_data_in_buddy(struct super_block *sb, { struct ext4_buddy e4b; struct ext4_group_info *db; - int err, count = 0, count2 = 0; + int err, count = 0; mb_debug(sb, "gonna free %u blocks in group %u (0x%p):", entry->efd_count, entry->efd_group, entry); @@ -3622,7 +3619,6 @@ static void ext4_free_data_in_buddy(struct super_block *sb, db = e4b.bd_info; /* there are blocks to put in buddy to make them really free */ count += entry->efd_count; - count2++; ext4_lock_group(sb, entry->efd_group); /* Take it out of per group rb tree */ rb_erase(&entry->efd_node, &(db->bb_free_root)); @@ -3647,8 +3643,7 @@ static void ext4_free_data_in_buddy(struct super_block *sb, ext4_unlock_group(sb, entry->efd_group); ext4_mb_unload_buddy(&e4b); - mb_debug(sb, "freed %d blocks in %d structures\n", count, - count2); + mb_debug(sb, "freed %d blocks in 1 structures\n", count); } /* @@ -3757,9 +3752,7 @@ ext4_mb_mark_diskspace_used(struct ext4_allocation_context *ac, bitmap_bh = ext4_read_block_bitmap(sb, ac->ac_b_ex.fe_group); if (IS_ERR(bitmap_bh)) { - err = PTR_ERR(bitmap_bh); - bitmap_bh = NULL; - goto out_err; + return PTR_ERR(bitmap_bh); } BUFFER_TRACE(bitmap_bh, "getting write access"); @@ -3822,7 +3815,7 @@ ext4_mb_mark_diskspace_used(struct ext4_allocation_context *ac, } len = ext4_free_group_clusters(sb, gdp) - ac->ac_b_ex.fe_len; ext4_free_group_clusters_set(sb, gdp, len); - ext4_block_bitmap_csum_set(sb, ac->ac_b_ex.fe_group, gdp, bitmap_bh); + ext4_block_bitmap_csum_set(sb, gdp, bitmap_bh); ext4_group_desc_csum_set(sb, ac->ac_b_ex.fe_group, gdp); ext4_unlock_group(sb, ac->ac_b_ex.fe_group); @@ -3929,7 +3922,7 @@ void ext4_mb_mark_bb(struct super_block *sb, ext4_fsblk_t block, clen = ext4_free_group_clusters(sb, gdp) + clen_changed; ext4_free_group_clusters_set(sb, gdp, clen); - ext4_block_bitmap_csum_set(sb, group, gdp, bitmap_bh); + ext4_block_bitmap_csum_set(sb, gdp, bitmap_bh); ext4_group_desc_csum_set(sb, group, gdp); ext4_unlock_group(sb, group); @@ -3985,6 +3978,197 @@ static void ext4_mb_normalize_group_request(struct ext4_allocation_context *ac) } /* + * This function returns the next element to look at during inode + * PA rbtree walk. We assume that we have held the inode PA rbtree lock + * (ei->i_prealloc_lock) + * + * new_start The start of the range we want to compare + * cur_start The existing start that we are comparing against + * node The node of the rb_tree + */ +static inline struct rb_node* +ext4_mb_pa_rb_next_iter(ext4_lblk_t new_start, ext4_lblk_t cur_start, struct rb_node *node) +{ + if (new_start < cur_start) + return node->rb_left; + else + return node->rb_right; +} + +static inline void +ext4_mb_pa_assert_overlap(struct ext4_allocation_context *ac, + ext4_lblk_t start, ext4_lblk_t end) +{ + struct ext4_sb_info *sbi = EXT4_SB(ac->ac_sb); + struct ext4_inode_info *ei = EXT4_I(ac->ac_inode); + struct ext4_prealloc_space *tmp_pa; + ext4_lblk_t tmp_pa_start, tmp_pa_end; + struct rb_node *iter; + + read_lock(&ei->i_prealloc_lock); + for (iter = ei->i_prealloc_node.rb_node; iter; + iter = ext4_mb_pa_rb_next_iter(start, tmp_pa_start, iter)) { + tmp_pa = rb_entry(iter, struct ext4_prealloc_space, + pa_node.inode_node); + tmp_pa_start = tmp_pa->pa_lstart; + tmp_pa_end = tmp_pa->pa_lstart + EXT4_C2B(sbi, tmp_pa->pa_len); + + spin_lock(&tmp_pa->pa_lock); + if (tmp_pa->pa_deleted == 0) + BUG_ON(!(start >= tmp_pa_end || end <= tmp_pa_start)); + spin_unlock(&tmp_pa->pa_lock); + } + read_unlock(&ei->i_prealloc_lock); +} + +/* + * Given an allocation context "ac" and a range "start", "end", check + * and adjust boundaries if the range overlaps with any of the existing + * preallocatoins stored in the corresponding inode of the allocation context. + * + * Parameters: + * ac allocation context + * start start of the new range + * end end of the new range + */ +static inline void +ext4_mb_pa_adjust_overlap(struct ext4_allocation_context *ac, + ext4_lblk_t *start, ext4_lblk_t *end) +{ + struct ext4_inode_info *ei = EXT4_I(ac->ac_inode); + struct ext4_sb_info *sbi = EXT4_SB(ac->ac_sb); + struct ext4_prealloc_space *tmp_pa = NULL, *left_pa = NULL, *right_pa = NULL; + struct rb_node *iter; + ext4_lblk_t new_start, new_end; + ext4_lblk_t tmp_pa_start, tmp_pa_end, left_pa_end = -1, right_pa_start = -1; + + new_start = *start; + new_end = *end; + + /* + * Adjust the normalized range so that it doesn't overlap with any + * existing preallocated blocks(PAs). Make sure to hold the rbtree lock + * so it doesn't change underneath us. + */ + read_lock(&ei->i_prealloc_lock); + + /* Step 1: find any one immediate neighboring PA of the normalized range */ + for (iter = ei->i_prealloc_node.rb_node; iter; + iter = ext4_mb_pa_rb_next_iter(ac->ac_o_ex.fe_logical, + tmp_pa_start, iter)) { + tmp_pa = rb_entry(iter, struct ext4_prealloc_space, + pa_node.inode_node); + tmp_pa_start = tmp_pa->pa_lstart; + tmp_pa_end = tmp_pa->pa_lstart + EXT4_C2B(sbi, tmp_pa->pa_len); + + /* PA must not overlap original request */ + spin_lock(&tmp_pa->pa_lock); + if (tmp_pa->pa_deleted == 0) + BUG_ON(!(ac->ac_o_ex.fe_logical >= tmp_pa_end || + ac->ac_o_ex.fe_logical < tmp_pa_start)); + spin_unlock(&tmp_pa->pa_lock); + } + + /* + * Step 2: check if the found PA is left or right neighbor and + * get the other neighbor + */ + if (tmp_pa) { + if (tmp_pa->pa_lstart < ac->ac_o_ex.fe_logical) { + struct rb_node *tmp; + + left_pa = tmp_pa; + tmp = rb_next(&left_pa->pa_node.inode_node); + if (tmp) { + right_pa = rb_entry(tmp, + struct ext4_prealloc_space, + pa_node.inode_node); + } + } else { + struct rb_node *tmp; + + right_pa = tmp_pa; + tmp = rb_prev(&right_pa->pa_node.inode_node); + if (tmp) { + left_pa = rb_entry(tmp, + struct ext4_prealloc_space, + pa_node.inode_node); + } + } + } + + /* Step 3: get the non deleted neighbors */ + if (left_pa) { + for (iter = &left_pa->pa_node.inode_node;; + iter = rb_prev(iter)) { + if (!iter) { + left_pa = NULL; + break; + } + + tmp_pa = rb_entry(iter, struct ext4_prealloc_space, + pa_node.inode_node); + left_pa = tmp_pa; + spin_lock(&tmp_pa->pa_lock); + if (tmp_pa->pa_deleted == 0) { + spin_unlock(&tmp_pa->pa_lock); + break; + } + spin_unlock(&tmp_pa->pa_lock); + } + } + + if (right_pa) { + for (iter = &right_pa->pa_node.inode_node;; + iter = rb_next(iter)) { + if (!iter) { + right_pa = NULL; + break; + } + + tmp_pa = rb_entry(iter, struct ext4_prealloc_space, + pa_node.inode_node); + right_pa = tmp_pa; + spin_lock(&tmp_pa->pa_lock); + if (tmp_pa->pa_deleted == 0) { + spin_unlock(&tmp_pa->pa_lock); + break; + } + spin_unlock(&tmp_pa->pa_lock); + } + } + + if (left_pa) { + left_pa_end = + left_pa->pa_lstart + EXT4_C2B(sbi, left_pa->pa_len); + BUG_ON(left_pa_end > ac->ac_o_ex.fe_logical); + } + + if (right_pa) { + right_pa_start = right_pa->pa_lstart; + BUG_ON(right_pa_start <= ac->ac_o_ex.fe_logical); + } + + /* Step 4: trim our normalized range to not overlap with the neighbors */ + if (left_pa) { + if (left_pa_end > new_start) + new_start = left_pa_end; + } + + if (right_pa) { + if (right_pa_start < new_end) + new_end = right_pa_start; + } + read_unlock(&ei->i_prealloc_lock); + + /* XXX: extra loop to check we really don't overlap preallocations */ + ext4_mb_pa_assert_overlap(ac, new_start, new_end); + + *start = new_start; + *end = new_end; +} + +/* * Normalization means making request better in terms of * size and alignment */ @@ -3993,13 +4177,12 @@ ext4_mb_normalize_request(struct ext4_allocation_context *ac, struct ext4_allocation_request *ar) { struct ext4_sb_info *sbi = EXT4_SB(ac->ac_sb); + struct ext4_super_block *es = sbi->s_es; int bsbits, max; ext4_lblk_t end; loff_t size, start_off; loff_t orig_size __maybe_unused; ext4_lblk_t start; - struct ext4_inode_info *ei = EXT4_I(ac->ac_inode); - struct ext4_prealloc_space *pa; /* do normalize only data requests, metadata requests do not need preallocation */ @@ -4068,7 +4251,7 @@ ext4_mb_normalize_request(struct ext4_allocation_context *ac, size = 8 * 1024 * 1024; } else { start_off = (loff_t) ac->ac_o_ex.fe_logical << bsbits; - size = (loff_t) EXT4_C2B(EXT4_SB(ac->ac_sb), + size = (loff_t) EXT4_C2B(sbi, ac->ac_o_ex.fe_len) << bsbits; } size = size >> bsbits; @@ -4100,61 +4283,10 @@ ext4_mb_normalize_request(struct ext4_allocation_context *ac, end = start + size; - /* check we don't cross already preallocated blocks */ - rcu_read_lock(); - list_for_each_entry_rcu(pa, &ei->i_prealloc_list, pa_inode_list) { - ext4_lblk_t pa_end; + ext4_mb_pa_adjust_overlap(ac, &start, &end); - if (pa->pa_deleted) - continue; - spin_lock(&pa->pa_lock); - if (pa->pa_deleted) { - spin_unlock(&pa->pa_lock); - continue; - } - - pa_end = pa->pa_lstart + EXT4_C2B(EXT4_SB(ac->ac_sb), - pa->pa_len); - - /* PA must not overlap original request */ - BUG_ON(!(ac->ac_o_ex.fe_logical >= pa_end || - ac->ac_o_ex.fe_logical < pa->pa_lstart)); - - /* skip PAs this normalized request doesn't overlap with */ - if (pa->pa_lstart >= end || pa_end <= start) { - spin_unlock(&pa->pa_lock); - continue; - } - BUG_ON(pa->pa_lstart <= start && pa_end >= end); - - /* adjust start or end to be adjacent to this pa */ - if (pa_end <= ac->ac_o_ex.fe_logical) { - BUG_ON(pa_end < start); - start = pa_end; - } else if (pa->pa_lstart > ac->ac_o_ex.fe_logical) { - BUG_ON(pa->pa_lstart > end); - end = pa->pa_lstart; - } - spin_unlock(&pa->pa_lock); - } - rcu_read_unlock(); size = end - start; - /* XXX: extra loop to check we really don't overlap preallocations */ - rcu_read_lock(); - list_for_each_entry_rcu(pa, &ei->i_prealloc_list, pa_inode_list) { - ext4_lblk_t pa_end; - - spin_lock(&pa->pa_lock); - if (pa->pa_deleted == 0) { - pa_end = pa->pa_lstart + EXT4_C2B(EXT4_SB(ac->ac_sb), - pa->pa_len); - BUG_ON(!(start >= pa_end || end <= pa->pa_lstart)); - } - spin_unlock(&pa->pa_lock); - } - rcu_read_unlock(); - /* * In this function "start" and "size" are normalized for better * alignment and length such that we could preallocate more blocks. @@ -4165,7 +4297,7 @@ ext4_mb_normalize_request(struct ext4_allocation_context *ac, * provide gurantee on number of contiguous blocks allocation since that * depends upon free space left, etc). * In case of inode pa, later we use the allocated blocks - * [pa_start + fe_logical - pa_lstart, fe_len/size] from the preallocated + * [pa_pstart + fe_logical - pa_lstart, fe_len/size] from the preallocated * range of goal/best blocks [start, size] to put it at the * ac_o_ex.fe_logical extent of this inode. * (See ext4_mb_use_inode_pa() for more details) @@ -4188,18 +4320,21 @@ ext4_mb_normalize_request(struct ext4_allocation_context *ac, ac->ac_g_ex.fe_len = EXT4_NUM_B2C(sbi, size); /* define goal start in order to merge */ - if (ar->pright && (ar->lright == (start + size))) { + if (ar->pright && (ar->lright == (start + size)) && + ar->pright >= size && + ar->pright - size >= le32_to_cpu(es->s_first_data_block)) { /* merge to the right */ ext4_get_group_no_and_offset(ac->ac_sb, ar->pright - size, - &ac->ac_f_ex.fe_group, - &ac->ac_f_ex.fe_start); + &ac->ac_g_ex.fe_group, + &ac->ac_g_ex.fe_start); ac->ac_flags |= EXT4_MB_HINT_TRY_GOAL; } - if (ar->pleft && (ar->lleft + 1 == start)) { + if (ar->pleft && (ar->lleft + 1 == start) && + ar->pleft + 1 < ext4_blocks_count(es)) { /* merge to the left */ ext4_get_group_no_and_offset(ac->ac_sb, ar->pleft + 1, - &ac->ac_f_ex.fe_group, - &ac->ac_f_ex.fe_start); + &ac->ac_g_ex.fe_group, + &ac->ac_g_ex.fe_start); ac->ac_flags |= EXT4_MB_HINT_TRY_GOAL; } @@ -4247,15 +4382,14 @@ static void ext4_discard_allocated_blocks(struct ext4_allocation_context *ac) if (ac->ac_f_ex.fe_len == 0) return; err = ext4_mb_load_buddy(ac->ac_sb, ac->ac_f_ex.fe_group, &e4b); - if (err) { + if (WARN_RATELIMIT(err, + "ext4: mb_load_buddy failed (%d)", err)) /* * This should never happen since we pin the * pages in the ext4_allocation_context so * ext4_mb_load_buddy() should never fail. */ - WARN(1, "mb_load_buddy failed (%d)", err); return; - } ext4_lock_group(ac->ac_sb, ac->ac_f_ex.fe_group); mb_free_blocks(ac->ac_inode, &e4b, ac->ac_f_ex.fe_start, ac->ac_f_ex.fe_len); @@ -4263,8 +4397,11 @@ static void ext4_discard_allocated_blocks(struct ext4_allocation_context *ac) ext4_mb_unload_buddy(&e4b); return; } - if (pa->pa_type == MB_INODE_PA) + if (pa->pa_type == MB_INODE_PA) { + spin_lock(&pa->pa_lock); pa->pa_free += ac->ac_b_ex.fe_len; + spin_unlock(&pa->pa_lock); + } } /* @@ -4292,6 +4429,7 @@ static void ext4_mb_use_inode_pa(struct ext4_allocation_context *ac, BUG_ON(start < pa->pa_pstart); BUG_ON(end > pa->pa_pstart + EXT4_C2B(sbi, pa->pa_len)); BUG_ON(pa->pa_free < len); + BUG_ON(ac->ac_b_ex.fe_len <= 0); pa->pa_free -= len; mb_debug(ac->ac_sb, "use %llu/%d from inode pa %p\n", start, len, pa); @@ -4312,14 +4450,14 @@ static void ext4_mb_use_group_pa(struct ext4_allocation_context *ac, ac->ac_status = AC_STATUS_FOUND; ac->ac_pa = pa; - /* we don't correct pa_pstart or pa_plen here to avoid + /* we don't correct pa_pstart or pa_len here to avoid * possible race when the group is being loaded concurrently * instead we correct pa later, after blocks are marked * in on-disk bitmap -- see ext4_mb_release_context() * Other CPUs are prevented from allocating from this pa by lg_mutex */ mb_debug(ac->ac_sb, "use %u/%u from group pa %p\n", - pa->pa_lstart-len, len, pa); + pa->pa_lstart, len, pa); } /* @@ -4361,7 +4499,9 @@ ext4_mb_use_preallocated(struct ext4_allocation_context *ac) int order, i; struct ext4_inode_info *ei = EXT4_I(ac->ac_inode); struct ext4_locality_group *lg; - struct ext4_prealloc_space *pa, *cpa = NULL; + struct ext4_prealloc_space *tmp_pa, *cpa = NULL; + ext4_lblk_t tmp_pa_start, tmp_pa_end; + struct rb_node *iter; ext4_fsblk_t goal_block; /* only data can be preallocated */ @@ -4369,35 +4509,47 @@ ext4_mb_use_preallocated(struct ext4_allocation_context *ac) return false; /* first, try per-file preallocation */ - rcu_read_lock(); - list_for_each_entry_rcu(pa, &ei->i_prealloc_list, pa_inode_list) { + read_lock(&ei->i_prealloc_lock); + for (iter = ei->i_prealloc_node.rb_node; iter; + iter = ext4_mb_pa_rb_next_iter(ac->ac_o_ex.fe_logical, + tmp_pa_start, iter)) { + tmp_pa = rb_entry(iter, struct ext4_prealloc_space, + pa_node.inode_node); /* all fields in this condition don't change, * so we can skip locking for them */ - if (ac->ac_o_ex.fe_logical < pa->pa_lstart || - ac->ac_o_ex.fe_logical >= (pa->pa_lstart + - EXT4_C2B(sbi, pa->pa_len))) + tmp_pa_start = tmp_pa->pa_lstart; + tmp_pa_end = tmp_pa->pa_lstart + EXT4_C2B(sbi, tmp_pa->pa_len); + + /* original request start doesn't lie in this PA */ + if (ac->ac_o_ex.fe_logical < tmp_pa_start || + ac->ac_o_ex.fe_logical >= tmp_pa_end) continue; /* non-extent files can't have physical blocks past 2^32 */ if (!(ext4_test_inode_flag(ac->ac_inode, EXT4_INODE_EXTENTS)) && - (pa->pa_pstart + EXT4_C2B(sbi, pa->pa_len) > - EXT4_MAX_BLOCK_FILE_PHYS)) - continue; + (tmp_pa->pa_pstart + EXT4_C2B(sbi, tmp_pa->pa_len) > + EXT4_MAX_BLOCK_FILE_PHYS)) { + /* + * Since PAs don't overlap, we won't find any + * other PA to satisfy this. + */ + break; + } /* found preallocated blocks, use them */ - spin_lock(&pa->pa_lock); - if (pa->pa_deleted == 0 && pa->pa_free) { - atomic_inc(&pa->pa_count); - ext4_mb_use_inode_pa(ac, pa); - spin_unlock(&pa->pa_lock); + spin_lock(&tmp_pa->pa_lock); + if (tmp_pa->pa_deleted == 0 && tmp_pa->pa_free) { + atomic_inc(&tmp_pa->pa_count); + ext4_mb_use_inode_pa(ac, tmp_pa); + spin_unlock(&tmp_pa->pa_lock); ac->ac_criteria = 10; - rcu_read_unlock(); + read_unlock(&ei->i_prealloc_lock); return true; } - spin_unlock(&pa->pa_lock); + spin_unlock(&tmp_pa->pa_lock); } - rcu_read_unlock(); + read_unlock(&ei->i_prealloc_lock); /* can we use group allocation? */ if (!(ac->ac_flags & EXT4_MB_HINT_GROUP_ALLOC)) @@ -4419,16 +4571,16 @@ ext4_mb_use_preallocated(struct ext4_allocation_context *ac) */ for (i = order; i < PREALLOC_TB_SIZE; i++) { rcu_read_lock(); - list_for_each_entry_rcu(pa, &lg->lg_prealloc_list[i], - pa_inode_list) { - spin_lock(&pa->pa_lock); - if (pa->pa_deleted == 0 && - pa->pa_free >= ac->ac_o_ex.fe_len) { + list_for_each_entry_rcu(tmp_pa, &lg->lg_prealloc_list[i], + pa_node.lg_list) { + spin_lock(&tmp_pa->pa_lock); + if (tmp_pa->pa_deleted == 0 && + tmp_pa->pa_free >= ac->ac_o_ex.fe_len) { cpa = ext4_mb_check_group_pa(goal_block, - pa, cpa); + tmp_pa, cpa); } - spin_unlock(&pa->pa_lock); + spin_unlock(&tmp_pa->pa_lock); } rcu_read_unlock(); } @@ -4525,16 +4677,22 @@ static void ext4_mb_mark_pa_deleted(struct super_block *sb, } } -static void ext4_mb_pa_callback(struct rcu_head *head) +static inline void ext4_mb_pa_free(struct ext4_prealloc_space *pa) { - struct ext4_prealloc_space *pa; - pa = container_of(head, struct ext4_prealloc_space, u.pa_rcu); - + BUG_ON(!pa); BUG_ON(atomic_read(&pa->pa_count)); BUG_ON(pa->pa_deleted == 0); kmem_cache_free(ext4_pspace_cachep, pa); } +static void ext4_mb_pa_callback(struct rcu_head *head) +{ + struct ext4_prealloc_space *pa; + + pa = container_of(head, struct ext4_prealloc_space, u.pa_rcu); + ext4_mb_pa_free(pa); +} + /* * drops a reference to preallocated space descriptor * if this was the last reference and the space is consumed @@ -4544,6 +4702,7 @@ static void ext4_mb_put_pa(struct ext4_allocation_context *ac, { ext4_group_t grp; ext4_fsblk_t grp_blk; + struct ext4_inode_info *ei = EXT4_I(ac->ac_inode); /* in this short window concurrent discard can set pa_deleted */ spin_lock(&pa->pa_lock); @@ -4588,11 +4747,42 @@ static void ext4_mb_put_pa(struct ext4_allocation_context *ac, list_del(&pa->pa_group_list); ext4_unlock_group(sb, grp); - spin_lock(pa->pa_obj_lock); - list_del_rcu(&pa->pa_inode_list); - spin_unlock(pa->pa_obj_lock); + if (pa->pa_type == MB_INODE_PA) { + write_lock(pa->pa_node_lock.inode_lock); + rb_erase(&pa->pa_node.inode_node, &ei->i_prealloc_node); + write_unlock(pa->pa_node_lock.inode_lock); + ext4_mb_pa_free(pa); + } else { + spin_lock(pa->pa_node_lock.lg_lock); + list_del_rcu(&pa->pa_node.lg_list); + spin_unlock(pa->pa_node_lock.lg_lock); + call_rcu(&(pa)->u.pa_rcu, ext4_mb_pa_callback); + } +} + +static void ext4_mb_pa_rb_insert(struct rb_root *root, struct rb_node *new) +{ + struct rb_node **iter = &root->rb_node, *parent = NULL; + struct ext4_prealloc_space *iter_pa, *new_pa; + ext4_lblk_t iter_start, new_start; + + while (*iter) { + iter_pa = rb_entry(*iter, struct ext4_prealloc_space, + pa_node.inode_node); + new_pa = rb_entry(new, struct ext4_prealloc_space, + pa_node.inode_node); + iter_start = iter_pa->pa_lstart; + new_start = new_pa->pa_lstart; + + parent = *iter; + if (new_start < iter_start) + iter = &((*iter)->rb_left); + else + iter = &((*iter)->rb_right); + } - call_rcu(&(pa)->u.pa_rcu, ext4_mb_pa_callback); + rb_link_node(new, parent, iter); + rb_insert_color(new, root); } /* @@ -4616,10 +4806,8 @@ ext4_mb_new_inode_pa(struct ext4_allocation_context *ac) pa = ac->ac_pa; if (ac->ac_b_ex.fe_len < ac->ac_g_ex.fe_len) { - int winl; - int wins; - int win; - int offs; + int new_bex_start; + int new_bex_end; /* we can't allocate as much as normalizer wants. * so, found space must get proper lstart @@ -4627,38 +4815,47 @@ ext4_mb_new_inode_pa(struct ext4_allocation_context *ac) BUG_ON(ac->ac_g_ex.fe_logical > ac->ac_o_ex.fe_logical); BUG_ON(ac->ac_g_ex.fe_len < ac->ac_o_ex.fe_len); - /* we're limited by original request in that - * logical block must be covered any way - * winl is window we can move our chunk within */ - winl = ac->ac_o_ex.fe_logical - ac->ac_g_ex.fe_logical; + /* + * Use the below logic for adjusting best extent as it keeps + * fragmentation in check while ensuring logical range of best + * extent doesn't overflow out of goal extent: + * + * 1. Check if best ex can be kept at end of goal and still + * cover original start + * 2. Else, check if best ex can be kept at start of goal and + * still cover original start + * 3. Else, keep the best ex at start of original request. + */ + new_bex_end = ac->ac_g_ex.fe_logical + + EXT4_C2B(sbi, ac->ac_g_ex.fe_len); + new_bex_start = new_bex_end - EXT4_C2B(sbi, ac->ac_b_ex.fe_len); + if (ac->ac_o_ex.fe_logical >= new_bex_start) + goto adjust_bex; - /* also, we should cover whole original request */ - wins = EXT4_C2B(sbi, ac->ac_b_ex.fe_len - ac->ac_o_ex.fe_len); + new_bex_start = ac->ac_g_ex.fe_logical; + new_bex_end = + new_bex_start + EXT4_C2B(sbi, ac->ac_b_ex.fe_len); + if (ac->ac_o_ex.fe_logical < new_bex_end) + goto adjust_bex; - /* the smallest one defines real window */ - win = min(winl, wins); + new_bex_start = ac->ac_o_ex.fe_logical; + new_bex_end = + new_bex_start + EXT4_C2B(sbi, ac->ac_b_ex.fe_len); - offs = ac->ac_o_ex.fe_logical % - EXT4_C2B(sbi, ac->ac_b_ex.fe_len); - if (offs && offs < win) - win = offs; +adjust_bex: + ac->ac_b_ex.fe_logical = new_bex_start; - ac->ac_b_ex.fe_logical = ac->ac_o_ex.fe_logical - - EXT4_NUM_B2C(sbi, win); BUG_ON(ac->ac_o_ex.fe_logical < ac->ac_b_ex.fe_logical); BUG_ON(ac->ac_o_ex.fe_len > ac->ac_b_ex.fe_len); + BUG_ON(new_bex_end > (ac->ac_g_ex.fe_logical + + EXT4_C2B(sbi, ac->ac_g_ex.fe_len))); } - /* preallocation can change ac_b_ex, thus we store actually - * allocated blocks for history */ - ac->ac_f_ex = ac->ac_b_ex; - pa->pa_lstart = ac->ac_b_ex.fe_logical; pa->pa_pstart = ext4_grp_offs_to_block(sb, &ac->ac_b_ex); pa->pa_len = ac->ac_b_ex.fe_len; pa->pa_free = pa->pa_len; spin_lock_init(&pa->pa_lock); - INIT_LIST_HEAD(&pa->pa_inode_list); INIT_LIST_HEAD(&pa->pa_group_list); pa->pa_deleted = 0; pa->pa_type = MB_INODE_PA; @@ -4667,20 +4864,20 @@ ext4_mb_new_inode_pa(struct ext4_allocation_context *ac) pa->pa_len, pa->pa_lstart); trace_ext4_mb_new_inode_pa(ac, pa); - ext4_mb_use_inode_pa(ac, pa); atomic_add(pa->pa_free, &sbi->s_mb_preallocated); + ext4_mb_use_inode_pa(ac, pa); ei = EXT4_I(ac->ac_inode); grp = ext4_get_group_info(sb, ac->ac_b_ex.fe_group); - pa->pa_obj_lock = &ei->i_prealloc_lock; + pa->pa_node_lock.inode_lock = &ei->i_prealloc_lock; pa->pa_inode = ac->ac_inode; list_add(&pa->pa_group_list, &grp->bb_prealloc_list); - spin_lock(pa->pa_obj_lock); - list_add_rcu(&pa->pa_inode_list, &ei->i_prealloc_list); - spin_unlock(pa->pa_obj_lock); + write_lock(pa->pa_node_lock.inode_lock); + ext4_mb_pa_rb_insert(&ei->i_prealloc_node, &pa->pa_node.inode_node); + write_unlock(pa->pa_node_lock.inode_lock); atomic_inc(&ei->i_prealloc_active); } @@ -4703,16 +4900,12 @@ ext4_mb_new_group_pa(struct ext4_allocation_context *ac) pa = ac->ac_pa; - /* preallocation can change ac_b_ex, thus we store actually - * allocated blocks for history */ - ac->ac_f_ex = ac->ac_b_ex; - pa->pa_pstart = ext4_grp_offs_to_block(sb, &ac->ac_b_ex); pa->pa_lstart = pa->pa_pstart; pa->pa_len = ac->ac_b_ex.fe_len; pa->pa_free = pa->pa_len; spin_lock_init(&pa->pa_lock); - INIT_LIST_HEAD(&pa->pa_inode_list); + INIT_LIST_HEAD(&pa->pa_node.lg_list); INIT_LIST_HEAD(&pa->pa_group_list); pa->pa_deleted = 0; pa->pa_type = MB_GROUP_PA; @@ -4728,7 +4921,7 @@ ext4_mb_new_group_pa(struct ext4_allocation_context *ac) lg = ac->ac_lg; BUG_ON(lg == NULL); - pa->pa_obj_lock = &lg->lg_prealloc_lock; + pa->pa_node_lock.lg_lock = &lg->lg_prealloc_lock; pa->pa_inode = NULL; list_add(&pa->pa_group_list, &grp->bb_prealloc_list); @@ -4846,6 +5039,7 @@ ext4_mb_discard_group_preallocations(struct super_block *sb, struct ext4_prealloc_space *pa, *tmp; struct list_head list; struct ext4_buddy e4b; + struct ext4_inode_info *ei; int err; int free = 0; @@ -4904,17 +5098,26 @@ ext4_mb_discard_group_preallocations(struct super_block *sb, list_for_each_entry_safe(pa, tmp, &list, u.pa_tmp_list) { /* remove from object (inode or locality group) */ - spin_lock(pa->pa_obj_lock); - list_del_rcu(&pa->pa_inode_list); - spin_unlock(pa->pa_obj_lock); + if (pa->pa_type == MB_GROUP_PA) { + spin_lock(pa->pa_node_lock.lg_lock); + list_del_rcu(&pa->pa_node.lg_list); + spin_unlock(pa->pa_node_lock.lg_lock); + } else { + write_lock(pa->pa_node_lock.inode_lock); + ei = EXT4_I(pa->pa_inode); + rb_erase(&pa->pa_node.inode_node, &ei->i_prealloc_node); + write_unlock(pa->pa_node_lock.inode_lock); + } - if (pa->pa_type == MB_GROUP_PA) + list_del(&pa->u.pa_tmp_list); + + if (pa->pa_type == MB_GROUP_PA) { ext4_mb_release_group_pa(&e4b, pa); - else + call_rcu(&(pa)->u.pa_rcu, ext4_mb_pa_callback); + } else { ext4_mb_release_inode_pa(&e4b, bitmap_bh, pa); - - list_del(&pa->u.pa_tmp_list); - call_rcu(&(pa)->u.pa_rcu, ext4_mb_pa_callback); + ext4_mb_pa_free(pa); + } } ext4_unlock_group(sb, group); @@ -4944,10 +5147,10 @@ void ext4_discard_preallocations(struct inode *inode, unsigned int needed) ext4_group_t group = 0; struct list_head list; struct ext4_buddy e4b; + struct rb_node *iter; int err; if (!S_ISREG(inode->i_mode)) { - /*BUG_ON(!list_empty(&ei->i_prealloc_list));*/ return; } @@ -4966,17 +5169,19 @@ void ext4_discard_preallocations(struct inode *inode, unsigned int needed) repeat: /* first, collect all pa's in the inode */ - spin_lock(&ei->i_prealloc_lock); - while (!list_empty(&ei->i_prealloc_list) && needed) { - pa = list_entry(ei->i_prealloc_list.prev, - struct ext4_prealloc_space, pa_inode_list); - BUG_ON(pa->pa_obj_lock != &ei->i_prealloc_lock); + write_lock(&ei->i_prealloc_lock); + for (iter = rb_first(&ei->i_prealloc_node); iter && needed; + iter = rb_next(iter)) { + pa = rb_entry(iter, struct ext4_prealloc_space, + pa_node.inode_node); + BUG_ON(pa->pa_node_lock.inode_lock != &ei->i_prealloc_lock); + spin_lock(&pa->pa_lock); if (atomic_read(&pa->pa_count)) { /* this shouldn't happen often - nobody should * use preallocation while we're discarding it */ spin_unlock(&pa->pa_lock); - spin_unlock(&ei->i_prealloc_lock); + write_unlock(&ei->i_prealloc_lock); ext4_msg(sb, KERN_ERR, "uh-oh! used pa while discarding"); WARN_ON(1); @@ -4987,7 +5192,7 @@ repeat: if (pa->pa_deleted == 0) { ext4_mb_mark_pa_deleted(sb, pa); spin_unlock(&pa->pa_lock); - list_del_rcu(&pa->pa_inode_list); + rb_erase(&pa->pa_node.inode_node, &ei->i_prealloc_node); list_add(&pa->u.pa_tmp_list, &list); needed--; continue; @@ -4995,7 +5200,7 @@ repeat: /* someone is deleting pa right now */ spin_unlock(&pa->pa_lock); - spin_unlock(&ei->i_prealloc_lock); + write_unlock(&ei->i_prealloc_lock); /* we have to wait here because pa_deleted * doesn't mean pa is already unlinked from @@ -5012,7 +5217,7 @@ repeat: schedule_timeout_uninterruptible(HZ); goto repeat; } - spin_unlock(&ei->i_prealloc_lock); + write_unlock(&ei->i_prealloc_lock); list_for_each_entry_safe(pa, tmp, &list, u.pa_tmp_list) { |