| // SPDX-License-Identifier: GPL-2.0 |
| /* |
| * fs/ext4/extents_status.c |
| * |
| * Written by Yongqiang Yang <xiaoqiangnk@gmail.com> |
| * Modified by |
| * Allison Henderson <achender@linux.vnet.ibm.com> |
| * Hugh Dickins <hughd@google.com> |
| * Zheng Liu <wenqing.lz@taobao.com> |
| * |
| * Ext4 extents status tree core functions. |
| */ |
| #include <linux/list_sort.h> |
| #include <linux/proc_fs.h> |
| #include <linux/seq_file.h> |
| #include "ext4.h" |
| |
| #include <trace/events/ext4.h> |
| |
| /* |
| * According to previous discussion in Ext4 Developer Workshop, we |
| * will introduce a new structure called io tree to track all extent |
| * status in order to solve some problems that we have met |
| * (e.g. Reservation space warning), and provide extent-level locking. |
| * Delay extent tree is the first step to achieve this goal. It is |
| * original built by Yongqiang Yang. At that time it is called delay |
| * extent tree, whose goal is only track delayed extents in memory to |
| * simplify the implementation of fiemap and bigalloc, and introduce |
| * lseek SEEK_DATA/SEEK_HOLE support. That is why it is still called |
| * delay extent tree at the first commit. But for better understand |
| * what it does, it has been rename to extent status tree. |
| * |
| * Step1: |
| * Currently the first step has been done. All delayed extents are |
| * tracked in the tree. It maintains the delayed extent when a delayed |
| * allocation is issued, and the delayed extent is written out or |
| * invalidated. Therefore the implementation of fiemap and bigalloc |
| * are simplified, and SEEK_DATA/SEEK_HOLE are introduced. |
| * |
| * The following comment describes the implemenmtation of extent |
| * status tree and future works. |
| * |
| * Step2: |
| * In this step all extent status are tracked by extent status tree. |
| * Thus, we can first try to lookup a block mapping in this tree before |
| * finding it in extent tree. Hence, single extent cache can be removed |
| * because extent status tree can do a better job. Extents in status |
| * tree are loaded on-demand. Therefore, the extent status tree may not |
| * contain all of the extents in a file. Meanwhile we define a shrinker |
| * to reclaim memory from extent status tree because fragmented extent |
| * tree will make status tree cost too much memory. written/unwritten/- |
| * hole extents in the tree will be reclaimed by this shrinker when we |
| * are under high memory pressure. Delayed extents will not be |
| * reclimed because fiemap, bigalloc, and seek_data/hole need it. |
| */ |
| |
| /* |
| * Extent status tree implementation for ext4. |
| * |
| * |
| * ========================================================================== |
| * Extent status tree tracks all extent status. |
| * |
| * 1. Why we need to implement extent status tree? |
| * |
| * Without extent status tree, ext4 identifies a delayed extent by looking |
| * up page cache, this has several deficiencies - complicated, buggy, |
| * and inefficient code. |
| * |
| * FIEMAP, SEEK_HOLE/DATA, bigalloc, and writeout all need to know if a |
| * block or a range of blocks are belonged to a delayed extent. |
| * |
| * Let us have a look at how they do without extent status tree. |
| * -- FIEMAP |
| * FIEMAP looks up page cache to identify delayed allocations from holes. |
| * |
| * -- SEEK_HOLE/DATA |
| * SEEK_HOLE/DATA has the same problem as FIEMAP. |
| * |
| * -- bigalloc |
| * bigalloc looks up page cache to figure out if a block is |
| * already under delayed allocation or not to determine whether |
| * quota reserving is needed for the cluster. |
| * |
| * -- writeout |
| * Writeout looks up whole page cache to see if a buffer is |
| * mapped, If there are not very many delayed buffers, then it is |
| * time consuming. |
| * |
| * With extent status tree implementation, FIEMAP, SEEK_HOLE/DATA, |
| * bigalloc and writeout can figure out if a block or a range of |
| * blocks is under delayed allocation(belonged to a delayed extent) or |
| * not by searching the extent tree. |
| * |
| * |
| * ========================================================================== |
| * 2. Ext4 extent status tree impelmentation |
| * |
| * -- extent |
| * A extent is a range of blocks which are contiguous logically and |
| * physically. Unlike extent in extent tree, this extent in ext4 is |
| * a in-memory struct, there is no corresponding on-disk data. There |
| * is no limit on length of extent, so an extent can contain as many |
| * blocks as they are contiguous logically and physically. |
| * |
| * -- extent status tree |
| * Every inode has an extent status tree and all allocation blocks |
| * are added to the tree with different status. The extent in the |
| * tree are ordered by logical block no. |
| * |
| * -- operations on a extent status tree |
| * There are three important operations on a delayed extent tree: find |
| * next extent, adding a extent(a range of blocks) and removing a extent. |
| * |
| * -- race on a extent status tree |
| * Extent status tree is protected by inode->i_es_lock. |
| * |
| * -- memory consumption |
| * Fragmented extent tree will make extent status tree cost too much |
| * memory. Hence, we will reclaim written/unwritten/hole extents from |
| * the tree under a heavy memory pressure. |
| * |
| * |
| * ========================================================================== |
| * 3. Performance analysis |
| * |
| * -- overhead |
| * 1. There is a cache extent for write access, so if writes are |
| * not very random, adding space operaions are in O(1) time. |
| * |
| * -- gain |
| * 2. Code is much simpler, more readable, more maintainable and |
| * more efficient. |
| * |
| * |
| * ========================================================================== |
| * 4. TODO list |
| * |
| * -- Refactor delayed space reservation |
| * |
| * -- Extent-level locking |
| */ |
| |
| static struct kmem_cache *ext4_es_cachep; |
| static struct kmem_cache *ext4_pending_cachep; |
| |
| static int __es_insert_extent(struct inode *inode, struct extent_status *newes); |
| static int __es_remove_extent(struct inode *inode, ext4_lblk_t lblk, |
| ext4_lblk_t end, int *reserved); |
| static int es_reclaim_extents(struct ext4_inode_info *ei, int *nr_to_scan); |
| static int __es_shrink(struct ext4_sb_info *sbi, int nr_to_scan, |
| struct ext4_inode_info *locked_ei); |
| static void __revise_pending(struct inode *inode, ext4_lblk_t lblk, |
| ext4_lblk_t len); |
| |
| int __init ext4_init_es(void) |
| { |
| ext4_es_cachep = kmem_cache_create("ext4_extent_status", |
| sizeof(struct extent_status), |
| 0, (SLAB_RECLAIM_ACCOUNT), NULL); |
| if (ext4_es_cachep == NULL) |
| return -ENOMEM; |
| return 0; |
| } |
| |
| void ext4_exit_es(void) |
| { |
| kmem_cache_destroy(ext4_es_cachep); |
| } |
| |
| void ext4_es_init_tree(struct ext4_es_tree *tree) |
| { |
| tree->root = RB_ROOT; |
| tree->cache_es = NULL; |
| } |
| |
| #ifdef ES_DEBUG__ |
| static void ext4_es_print_tree(struct inode *inode) |
| { |
| struct ext4_es_tree *tree; |
| struct rb_node *node; |
| |
| printk(KERN_DEBUG "status extents for inode %lu:", inode->i_ino); |
| tree = &EXT4_I(inode)->i_es_tree; |
| node = rb_first(&tree->root); |
| while (node) { |
| struct extent_status *es; |
| es = rb_entry(node, struct extent_status, rb_node); |
| printk(KERN_DEBUG " [%u/%u) %llu %x", |
| es->es_lblk, es->es_len, |
| ext4_es_pblock(es), ext4_es_status(es)); |
| node = rb_next(node); |
| } |
| printk(KERN_DEBUG "\n"); |
| } |
| #else |
| #define ext4_es_print_tree(inode) |
| #endif |
| |
| static inline ext4_lblk_t ext4_es_end(struct extent_status *es) |
| { |
| BUG_ON(es->es_lblk + es->es_len < es->es_lblk); |
| return es->es_lblk + es->es_len - 1; |
| } |
| |
| /* |
| * search through the tree for an delayed extent with a given offset. If |
| * it can't be found, try to find next extent. |
| */ |
| static struct extent_status *__es_tree_search(struct rb_root *root, |
| ext4_lblk_t lblk) |
| { |
| struct rb_node *node = root->rb_node; |
| struct extent_status *es = NULL; |
| |
| while (node) { |
| es = rb_entry(node, struct extent_status, rb_node); |
| if (lblk < es->es_lblk) |
| node = node->rb_left; |
| else if (lblk > ext4_es_end(es)) |
| node = node->rb_right; |
| else |
| return es; |
| } |
| |
| if (es && lblk < es->es_lblk) |
| return es; |
| |
| if (es && lblk > ext4_es_end(es)) { |
| node = rb_next(&es->rb_node); |
| return node ? rb_entry(node, struct extent_status, rb_node) : |
| NULL; |
| } |
| |
| return NULL; |
| } |
| |
| /* |
| * ext4_es_find_extent_range - find extent with specified status within block |
| * range or next extent following block range in |
| * extents status tree |
| * |
| * @inode - file containing the range |
| * @matching_fn - pointer to function that matches extents with desired status |
| * @lblk - logical block defining start of range |
| * @end - logical block defining end of range |
| * @es - extent found, if any |
| * |
| * Find the first extent within the block range specified by @lblk and @end |
| * in the extents status tree that satisfies @matching_fn. If a match |
| * is found, it's returned in @es. If not, and a matching extent is found |
| * beyond the block range, it's returned in @es. If no match is found, an |
| * extent is returned in @es whose es_lblk, es_len, and es_pblk components |
| * are 0. |
| */ |
| static void __es_find_extent_range(struct inode *inode, |
| int (*matching_fn)(struct extent_status *es), |
| ext4_lblk_t lblk, ext4_lblk_t end, |
| struct extent_status *es) |
| { |
| struct ext4_es_tree *tree = NULL; |
| struct extent_status *es1 = NULL; |
| struct rb_node *node; |
| |
| WARN_ON(es == NULL); |
| WARN_ON(end < lblk); |
| |
| tree = &EXT4_I(inode)->i_es_tree; |
| |
| /* see if the extent has been cached */ |
| es->es_lblk = es->es_len = es->es_pblk = 0; |
| if (tree->cache_es) { |
| es1 = tree->cache_es; |
| if (in_range(lblk, es1->es_lblk, es1->es_len)) { |
| es_debug("%u cached by [%u/%u) %llu %x\n", |
| lblk, es1->es_lblk, es1->es_len, |
| ext4_es_pblock(es1), ext4_es_status(es1)); |
| goto out; |
| } |
| } |
| |
| es1 = __es_tree_search(&tree->root, lblk); |
| |
| out: |
| if (es1 && !matching_fn(es1)) { |
| while ((node = rb_next(&es1->rb_node)) != NULL) { |
| es1 = rb_entry(node, struct extent_status, rb_node); |
| if (es1->es_lblk > end) { |
| es1 = NULL; |
| break; |
| } |
| if (matching_fn(es1)) |
| break; |
| } |
| } |
| |
| if (es1 && matching_fn(es1)) { |
| tree->cache_es = es1; |
| es->es_lblk = es1->es_lblk; |
| es->es_len = es1->es_len; |
| es->es_pblk = es1->es_pblk; |
| } |
| |
| } |
| |
| /* |
| * Locking for __es_find_extent_range() for external use |
| */ |
| void ext4_es_find_extent_range(struct inode *inode, |
| int (*matching_fn)(struct extent_status *es), |
| ext4_lblk_t lblk, ext4_lblk_t end, |
| struct extent_status *es) |
| { |
| trace_ext4_es_find_extent_range_enter(inode, lblk); |
| |
| read_lock(&EXT4_I(inode)->i_es_lock); |
| __es_find_extent_range(inode, matching_fn, lblk, end, es); |
| read_unlock(&EXT4_I(inode)->i_es_lock); |
| |
| trace_ext4_es_find_extent_range_exit(inode, es); |
| } |
| |
| /* |
| * __es_scan_range - search block range for block with specified status |
| * in extents status tree |
| * |
| * @inode - file containing the range |
| * @matching_fn - pointer to function that matches extents with desired status |
| * @lblk - logical block defining start of range |
| * @end - logical block defining end of range |
| * |
| * Returns true if at least one block in the specified block range satisfies |
| * the criterion specified by @matching_fn, and false if not. If at least |
| * one extent has the specified status, then there is at least one block |
| * in the cluster with that status. Should only be called by code that has |
| * taken i_es_lock. |
| */ |
| static bool __es_scan_range(struct inode *inode, |
| int (*matching_fn)(struct extent_status *es), |
| ext4_lblk_t start, ext4_lblk_t end) |
| { |
| struct extent_status es; |
| |
| __es_find_extent_range(inode, matching_fn, start, end, &es); |
| if (es.es_len == 0) |
| return false; /* no matching extent in the tree */ |
| else if (es.es_lblk <= start && |
| start < es.es_lblk + es.es_len) |
| return true; |
| else if (start <= es.es_lblk && es.es_lblk <= end) |
| return true; |
| else |
| return false; |
| } |
| /* |
| * Locking for __es_scan_range() for external use |
| */ |
| bool ext4_es_scan_range(struct inode *inode, |
| int (*matching_fn)(struct extent_status *es), |
| ext4_lblk_t lblk, ext4_lblk_t end) |
| { |
| bool ret; |
| |
| read_lock(&EXT4_I(inode)->i_es_lock); |
| ret = __es_scan_range(inode, matching_fn, lblk, end); |
| read_unlock(&EXT4_I(inode)->i_es_lock); |
| |
| return ret; |
| } |
| |
| /* |
| * __es_scan_clu - search cluster for block with specified status in |
| * extents status tree |
| * |
| * @inode - file containing the cluster |
| * @matching_fn - pointer to function that matches extents with desired status |
| * @lblk - logical block in cluster to be searched |
| * |
| * Returns true if at least one extent in the cluster containing @lblk |
| * satisfies the criterion specified by @matching_fn, and false if not. If at |
| * least one extent has the specified status, then there is at least one block |
| * in the cluster with that status. Should only be called by code that has |
| * taken i_es_lock. |
| */ |
| static bool __es_scan_clu(struct inode *inode, |
| int (*matching_fn)(struct extent_status *es), |
| ext4_lblk_t lblk) |
| { |
| struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); |
| ext4_lblk_t lblk_start, lblk_end; |
| |
| lblk_start = EXT4_LBLK_CMASK(sbi, lblk); |
| lblk_end = lblk_start + sbi->s_cluster_ratio - 1; |
| |
| return __es_scan_range(inode, matching_fn, lblk_start, lblk_end); |
| } |
| |
| /* |
| * Locking for __es_scan_clu() for external use |
| */ |
| bool ext4_es_scan_clu(struct inode *inode, |
| int (*matching_fn)(struct extent_status *es), |
| ext4_lblk_t lblk) |
| { |
| bool ret; |
| |
| read_lock(&EXT4_I(inode)->i_es_lock); |
| ret = __es_scan_clu(inode, matching_fn, lblk); |
| read_unlock(&EXT4_I(inode)->i_es_lock); |
| |
| return ret; |
| } |
| |
| static void ext4_es_list_add(struct inode *inode) |
| { |
| struct ext4_inode_info *ei = EXT4_I(inode); |
| struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); |
| |
| if (!list_empty(&ei->i_es_list)) |
| return; |
| |
| spin_lock(&sbi->s_es_lock); |
| if (list_empty(&ei->i_es_list)) { |
| list_add_tail(&ei->i_es_list, &sbi->s_es_list); |
| sbi->s_es_nr_inode++; |
| } |
| spin_unlock(&sbi->s_es_lock); |
| } |
| |
| static void ext4_es_list_del(struct inode *inode) |
| { |
| struct ext4_inode_info *ei = EXT4_I(inode); |
| struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); |
| |
| spin_lock(&sbi->s_es_lock); |
| if (!list_empty(&ei->i_es_list)) { |
| list_del_init(&ei->i_es_list); |
| sbi->s_es_nr_inode--; |
| WARN_ON_ONCE(sbi->s_es_nr_inode < 0); |
| } |
| spin_unlock(&sbi->s_es_lock); |
| } |
| |
| static struct extent_status * |
| ext4_es_alloc_extent(struct inode *inode, ext4_lblk_t lblk, ext4_lblk_t len, |
| ext4_fsblk_t pblk) |
| { |
| struct extent_status *es; |
| es = kmem_cache_alloc(ext4_es_cachep, GFP_ATOMIC); |
| if (es == NULL) |
| return NULL; |
| es->es_lblk = lblk; |
| es->es_len = len; |
| es->es_pblk = pblk; |
| |
| /* |
| * We don't count delayed extent because we never try to reclaim them |
| */ |
| if (!ext4_es_is_delayed(es)) { |
| if (!EXT4_I(inode)->i_es_shk_nr++) |
| ext4_es_list_add(inode); |
| percpu_counter_inc(&EXT4_SB(inode->i_sb)-> |
| s_es_stats.es_stats_shk_cnt); |
| } |
| |
| EXT4_I(inode)->i_es_all_nr++; |
| percpu_counter_inc(&EXT4_SB(inode->i_sb)->s_es_stats.es_stats_all_cnt); |
| |
| return es; |
| } |
| |
| static void ext4_es_free_extent(struct inode *inode, struct extent_status *es) |
| { |
| EXT4_I(inode)->i_es_all_nr--; |
| percpu_counter_dec(&EXT4_SB(inode->i_sb)->s_es_stats.es_stats_all_cnt); |
| |
| /* Decrease the shrink counter when this es is not delayed */ |
| if (!ext4_es_is_delayed(es)) { |
| BUG_ON(EXT4_I(inode)->i_es_shk_nr == 0); |
| if (!--EXT4_I(inode)->i_es_shk_nr) |
| ext4_es_list_del(inode); |
| percpu_counter_dec(&EXT4_SB(inode->i_sb)-> |
| s_es_stats.es_stats_shk_cnt); |
| } |
| |
| kmem_cache_free(ext4_es_cachep, es); |
| } |
| |
| /* |
| * Check whether or not two extents can be merged |
| * Condition: |
| * - logical block number is contiguous |
| * - physical block number is contiguous |
| * - status is equal |
| */ |
| static int ext4_es_can_be_merged(struct extent_status *es1, |
| struct extent_status *es2) |
| { |
| if (ext4_es_type(es1) != ext4_es_type(es2)) |
| return 0; |
| |
| if (((__u64) es1->es_len) + es2->es_len > EXT_MAX_BLOCKS) { |
| pr_warn("ES assertion failed when merging extents. " |
| "The sum of lengths of es1 (%d) and es2 (%d) " |
| "is bigger than allowed file size (%d)\n", |
| es1->es_len, es2->es_len, EXT_MAX_BLOCKS); |
| WARN_ON(1); |
| return 0; |
| } |
| |
| if (((__u64) es1->es_lblk) + es1->es_len != es2->es_lblk) |
| return 0; |
| |
| if ((ext4_es_is_written(es1) || ext4_es_is_unwritten(es1)) && |
| (ext4_es_pblock(es1) + es1->es_len == ext4_es_pblock(es2))) |
| return 1; |
| |
| if (ext4_es_is_hole(es1)) |
| return 1; |
| |
| /* we need to check delayed extent is without unwritten status */ |
| if (ext4_es_is_delayed(es1) && !ext4_es_is_unwritten(es1)) |
| return 1; |
| |
| return 0; |
| } |
| |
| static struct extent_status * |
| ext4_es_try_to_merge_left(struct inode *inode, struct extent_status *es) |
| { |
| struct ext4_es_tree *tree = &EXT4_I(inode)->i_es_tree; |
| struct extent_status *es1; |
| struct rb_node *node; |
| |
| node = rb_prev(&es->rb_node); |
| if (!node) |
| return es; |
| |
| es1 = rb_entry(node, struct extent_status, rb_node); |
| if (ext4_es_can_be_merged(es1, es)) { |
| es1->es_len += es->es_len; |
| if (ext4_es_is_referenced(es)) |
| ext4_es_set_referenced(es1); |
| rb_erase(&es->rb_node, &tree->root); |
| ext4_es_free_extent(inode, es); |
| es = es1; |
| } |
| |
| return es; |
| } |
| |
| static struct extent_status * |
| ext4_es_try_to_merge_right(struct inode *inode, struct extent_status *es) |
| { |
| struct ext4_es_tree *tree = &EXT4_I(inode)->i_es_tree; |
| struct extent_status *es1; |
| struct rb_node *node; |
| |
| node = rb_next(&es->rb_node); |
| if (!node) |
| return es; |
| |
| es1 = rb_entry(node, struct extent_status, rb_node); |
| if (ext4_es_can_be_merged(es, es1)) { |
| es->es_len += es1->es_len; |
| if (ext4_es_is_referenced(es1)) |
| ext4_es_set_referenced(es); |
| rb_erase(node, &tree->root); |
| ext4_es_free_extent(inode, es1); |
| } |
| |
| return es; |
| } |
| |
| #ifdef ES_AGGRESSIVE_TEST |
| #include "ext4_extents.h" /* Needed when ES_AGGRESSIVE_TEST is defined */ |
| |
| static void ext4_es_insert_extent_ext_check(struct inode *inode, |
| struct extent_status *es) |
| { |
| struct ext4_ext_path *path = NULL; |
| struct ext4_extent *ex; |
| ext4_lblk_t ee_block; |
| ext4_fsblk_t ee_start; |
| unsigned short ee_len; |
| int depth, ee_status, es_status; |
| |
| path = ext4_find_extent(inode, es->es_lblk, NULL, EXT4_EX_NOCACHE); |
| if (IS_ERR(path)) |
| return; |
| |
| depth = ext_depth(inode); |
| ex = path[depth].p_ext; |
| |
| if (ex) { |
| |
| ee_block = le32_to_cpu(ex->ee_block); |
| ee_start = ext4_ext_pblock(ex); |
| ee_len = ext4_ext_get_actual_len(ex); |
| |
| ee_status = ext4_ext_is_unwritten(ex) ? 1 : 0; |
| es_status = ext4_es_is_unwritten(es) ? 1 : 0; |
| |
| /* |
| * Make sure ex and es are not overlap when we try to insert |
| * a delayed/hole extent. |
| */ |
| if (!ext4_es_is_written(es) && !ext4_es_is_unwritten(es)) { |
| if (in_range(es->es_lblk, ee_block, ee_len)) { |
| pr_warn("ES insert assertion failed for " |
| "inode: %lu we can find an extent " |
| "at block [%d/%d/%llu/%c], but we " |
| "want to add a delayed/hole extent " |
| "[%d/%d/%llu/%x]\n", |
| inode->i_ino, ee_block, ee_len, |
| ee_start, ee_status ? 'u' : 'w', |
| es->es_lblk, es->es_len, |
| ext4_es_pblock(es), ext4_es_status(es)); |
| } |
| goto out; |
| } |
| |
| /* |
| * We don't check ee_block == es->es_lblk, etc. because es |
| * might be a part of whole extent, vice versa. |
| */ |
| if (es->es_lblk < ee_block || |
| ext4_es_pblock(es) != ee_start + es->es_lblk - ee_block) { |
| pr_warn("ES insert assertion failed for inode: %lu " |
| "ex_status [%d/%d/%llu/%c] != " |
| "es_status [%d/%d/%llu/%c]\n", inode->i_ino, |
| ee_block, ee_len, ee_start, |
| ee_status ? 'u' : 'w', es->es_lblk, es->es_len, |
| ext4_es_pblock(es), es_status ? 'u' : 'w'); |
| goto out; |
| } |
| |
| if (ee_status ^ es_status) { |
| pr_warn("ES insert assertion failed for inode: %lu " |
| "ex_status [%d/%d/%llu/%c] != " |
| "es_status [%d/%d/%llu/%c]\n", inode->i_ino, |
| ee_block, ee_len, ee_start, |
| ee_status ? 'u' : 'w', es->es_lblk, es->es_len, |
| ext4_es_pblock(es), es_status ? 'u' : 'w'); |
| } |
| } else { |
| /* |
| * We can't find an extent on disk. So we need to make sure |
| * that we don't want to add an written/unwritten extent. |
| */ |
| if (!ext4_es_is_delayed(es) && !ext4_es_is_hole(es)) { |
| pr_warn("ES insert assertion failed for inode: %lu " |
| "can't find an extent at block %d but we want " |
| "to add a written/unwritten extent " |
| "[%d/%d/%llu/%x]\n", inode->i_ino, |
| es->es_lblk, es->es_lblk, es->es_len, |
| ext4_es_pblock(es), ext4_es_status(es)); |
| } |
| } |
| out: |
| ext4_ext_drop_refs(path); |
| kfree(path); |
| } |
| |
| static void ext4_es_insert_extent_ind_check(struct inode *inode, |
| struct extent_status *es) |
| { |
| struct ext4_map_blocks map; |
| int retval; |
| |
| /* |
| * Here we call ext4_ind_map_blocks to lookup a block mapping because |
| * 'Indirect' structure is defined in indirect.c. So we couldn't |
| * access direct/indirect tree from outside. It is too dirty to define |
| * this function in indirect.c file. |
| */ |
| |
| map.m_lblk = es->es_lblk; |
| map.m_len = es->es_len; |
| |
| retval = ext4_ind_map_blocks(NULL, inode, &map, 0); |
| if (retval > 0) { |
| if (ext4_es_is_delayed(es) || ext4_es_is_hole(es)) { |
| /* |
| * We want to add a delayed/hole extent but this |
| * block has been allocated. |
| */ |
| pr_warn("ES insert assertion failed for inode: %lu " |
| "We can find blocks but we want to add a " |
| "delayed/hole extent [%d/%d/%llu/%x]\n", |
| inode->i_ino, es->es_lblk, es->es_len, |
| ext4_es_pblock(es), ext4_es_status(es)); |
| return; |
| } else if (ext4_es_is_written(es)) { |
| if (retval != es->es_len) { |
| pr_warn("ES insert assertion failed for " |
| "inode: %lu retval %d != es_len %d\n", |
| inode->i_ino, retval, es->es_len); |
| return; |
| } |
| if (map.m_pblk != ext4_es_pblock(es)) { |
| pr_warn("ES insert assertion failed for " |
| "inode: %lu m_pblk %llu != " |
| "es_pblk %llu\n", |
| inode->i_ino, map.m_pblk, |
| ext4_es_pblock(es)); |
| return; |
| } |
| } else { |
| /* |
| * We don't need to check unwritten extent because |
| * indirect-based file doesn't have it. |
| */ |
| BUG(); |
| } |
| } else if (retval == 0) { |
| if (ext4_es_is_written(es)) { |
| pr_warn("ES insert assertion failed for inode: %lu " |
| "We can't find the block but we want to add " |
| "a written extent [%d/%d/%llu/%x]\n", |
| inode->i_ino, es->es_lblk, es->es_len, |
| ext4_es_pblock(es), ext4_es_status(es)); |
| return; |
| } |
| } |
| } |
| |
| static inline void ext4_es_insert_extent_check(struct inode *inode, |
| struct extent_status *es) |
| { |
| /* |
| * We don't need to worry about the race condition because |
| * caller takes i_data_sem locking. |
| */ |
| BUG_ON(!rwsem_is_locked(&EXT4_I(inode)->i_data_sem)); |
| if (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)) |
| ext4_es_insert_extent_ext_check(inode, es); |
| else |
| ext4_es_insert_extent_ind_check(inode, es); |
| } |
| #else |
| static inline void ext4_es_insert_extent_check(struct inode *inode, |
| struct extent_status *es) |
| { |
| } |
| #endif |
| |
| static int __es_insert_extent(struct inode *inode, struct extent_status *newes) |
| { |
| struct ext4_es_tree *tree = &EXT4_I(inode)->i_es_tree; |
| struct rb_node **p = &tree->root.rb_node; |
| struct rb_node *parent = NULL; |
| struct extent_status *es; |
| |
| while (*p) { |
| parent = *p; |
| es = rb_entry(parent, struct extent_status, rb_node); |
| |
| if (newes->es_lblk < es->es_lblk) { |
| if (ext4_es_can_be_merged(newes, es)) { |
| /* |
| * Here we can modify es_lblk directly |
| * because it isn't overlapped. |
| */ |
| es->es_lblk = newes->es_lblk; |
| es->es_len += newes->es_len; |
| if (ext4_es_is_written(es) || |
| ext4_es_is_unwritten(es)) |
| ext4_es_store_pblock(es, |
| newes->es_pblk); |
| es = ext4_es_try_to_merge_left(inode, es); |
| goto out; |
| } |
| p = &(*p)->rb_left; |
| } else if (newes->es_lblk > ext4_es_end(es)) { |
| if (ext4_es_can_be_merged(es, newes)) { |
| es->es_len += newes->es_len; |
| es = ext4_es_try_to_merge_right(inode, es); |
| goto out; |
| } |
| p = &(*p)->rb_right; |
| } else { |
| BUG(); |
| return -EINVAL; |
| } |
| } |
| |
| es = ext4_es_alloc_extent(inode, newes->es_lblk, newes->es_len, |
| newes->es_pblk); |
| if (!es) |
| return -ENOMEM; |
| rb_link_node(&es->rb_node, parent, p); |
| rb_insert_color(&es->rb_node, &tree->root); |
| |
| out: |
| tree->cache_es = es; |
| return 0; |
| } |
| |
| /* |
| * ext4_es_insert_extent() adds information to an inode's extent |
| * status tree. |
| * |
| * Return 0 on success, error code on failure. |
| */ |
| int ext4_es_insert_extent(struct inode *inode, ext4_lblk_t lblk, |
| ext4_lblk_t len, ext4_fsblk_t pblk, |
| unsigned int status) |
| { |
| struct extent_status newes; |
| ext4_lblk_t end = lblk + len - 1; |
| int err = 0; |
| struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); |
| |
| es_debug("add [%u/%u) %llu %x to extent status tree of inode %lu\n", |
| lblk, len, pblk, status, inode->i_ino); |
| |
| if (!len) |
| return 0; |
| |
| BUG_ON(end < lblk); |
| |
| if ((status & EXTENT_STATUS_DELAYED) && |
| (status & EXTENT_STATUS_WRITTEN)) { |
| ext4_warning(inode->i_sb, "Inserting extent [%u/%u] as " |
| " delayed and written which can potentially " |
| " cause data loss.", lblk, len); |
| WARN_ON(1); |
| } |
| |
| newes.es_lblk = lblk; |
| newes.es_len = len; |
| ext4_es_store_pblock_status(&newes, pblk, status); |
| trace_ext4_es_insert_extent(inode, &newes); |
| |
| ext4_es_insert_extent_check(inode, &newes); |
| |
| write_lock(&EXT4_I(inode)->i_es_lock); |
| err = __es_remove_extent(inode, lblk, end, NULL); |
| if (err != 0) |
| goto error; |
| retry: |
| err = __es_insert_extent(inode, &newes); |
| if (err == -ENOMEM && __es_shrink(EXT4_SB(inode->i_sb), |
| 128, EXT4_I(inode))) |
| goto retry; |
| if (err == -ENOMEM && !ext4_es_is_delayed(&newes)) |
| err = 0; |
| |
| if (sbi->s_cluster_ratio > 1 && test_opt(inode->i_sb, DELALLOC) && |
| (status & EXTENT_STATUS_WRITTEN || |
| status & EXTENT_STATUS_UNWRITTEN)) |
| __revise_pending(inode, lblk, len); |
| |
| error: |
| write_unlock(&EXT4_I(inode)->i_es_lock); |
| |
| ext4_es_print_tree(inode); |
| |
| return err; |
| } |
| |
| /* |
| * ext4_es_cache_extent() inserts information into the extent status |
| * tree if and only if there isn't information about the range in |
| * question already. |
| */ |
| void ext4_es_cache_extent(struct inode *inode, ext4_lblk_t lblk, |
| ext4_lblk_t len, ext4_fsblk_t pblk, |
| unsigned int status) |
| { |
| struct extent_status *es; |
| struct extent_status newes; |
| ext4_lblk_t end = lblk + len - 1; |
| |
| newes.es_lblk = lblk; |
| newes.es_len = len; |
| ext4_es_store_pblock_status(&newes, pblk, status); |
| trace_ext4_es_cache_extent(inode, &newes); |
| |
| if (!len) |
| return; |
| |
| BUG_ON(end < lblk); |
| |
| write_lock(&EXT4_I(inode)->i_es_lock); |
| |
| es = __es_tree_search(&EXT4_I(inode)->i_es_tree.root, lblk); |
| if (!es || es->es_lblk > end) |
| __es_insert_extent(inode, &newes); |
| write_unlock(&EXT4_I(inode)->i_es_lock); |
| } |
| |
| /* |
| * ext4_es_lookup_extent() looks up an extent in extent status tree. |
| * |
| * ext4_es_lookup_extent is called by ext4_map_blocks/ext4_da_map_blocks. |
| * |
| * Return: 1 on found, 0 on not |
| */ |
| int ext4_es_lookup_extent(struct inode *inode, ext4_lblk_t lblk, |
| ext4_lblk_t *next_lblk, |
| struct extent_status *es) |
| { |
| struct ext4_es_tree *tree; |
| struct ext4_es_stats *stats; |
| struct extent_status *es1 = NULL; |
| struct rb_node *node; |
| int found = 0; |
| |
| trace_ext4_es_lookup_extent_enter(inode, lblk); |
| es_debug("lookup extent in block %u\n", lblk); |
| |
| tree = &EXT4_I(inode)->i_es_tree; |
| read_lock(&EXT4_I(inode)->i_es_lock); |
| |
| /* find extent in cache firstly */ |
| es->es_lblk = es->es_len = es->es_pblk = 0; |
| if (tree->cache_es) { |
| es1 = tree->cache_es; |
| if (in_range(lblk, es1->es_lblk, es1->es_len)) { |
| es_debug("%u cached by [%u/%u)\n", |
| lblk, es1->es_lblk, es1->es_len); |
| found = 1; |
| goto out; |
| } |
| } |
| |
| node = tree->root.rb_node; |
| while (node) { |
| es1 = rb_entry(node, struct extent_status, rb_node); |
| if (lblk < es1->es_lblk) |
| node = node->rb_left; |
| else if (lblk > ext4_es_end(es1)) |
| node = node->rb_right; |
| else { |
| found = 1; |
| break; |
| } |
| } |
| |
| out: |
| stats = &EXT4_SB(inode->i_sb)->s_es_stats; |
| if (found) { |
| BUG_ON(!es1); |
| es->es_lblk = es1->es_lblk; |
| es->es_len = es1->es_len; |
| es->es_pblk = es1->es_pblk; |
| if (!ext4_es_is_referenced(es1)) |
| ext4_es_set_referenced(es1); |
| percpu_counter_inc(&stats->es_stats_cache_hits); |
| if (next_lblk) { |
| node = rb_next(&es1->rb_node); |
| if (node) { |
| es1 = rb_entry(node, struct extent_status, |
| rb_node); |
| *next_lblk = es1->es_lblk; |
| } else |
| *next_lblk = 0; |
| } |
| } else { |
| percpu_counter_inc(&stats->es_stats_cache_misses); |
| } |
| |
| read_unlock(&EXT4_I(inode)->i_es_lock); |
| |
| trace_ext4_es_lookup_extent_exit(inode, es, found); |
| return found; |
| } |
| |
| struct rsvd_count { |
| int ndelonly; |
| bool first_do_lblk_found; |
| ext4_lblk_t first_do_lblk; |
| ext4_lblk_t last_do_lblk; |
| struct extent_status *left_es; |
| bool partial; |
| ext4_lblk_t lclu; |
| }; |
| |
| /* |
| * init_rsvd - initialize reserved count data before removing block range |
| * in file from extent status tree |
| * |
| * @inode - file containing range |
| * @lblk - first block in range |
| * @es - pointer to first extent in range |
| * @rc - pointer to reserved count data |
| * |
| * Assumes es is not NULL |
| */ |
| static void init_rsvd(struct inode *inode, ext4_lblk_t lblk, |
| struct extent_status *es, struct rsvd_count *rc) |
| { |
| struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); |
| struct rb_node *node; |
| |
| rc->ndelonly = 0; |
| |
| /* |
| * for bigalloc, note the first delonly block in the range has not |
| * been found, record the extent containing the block to the left of |
| * the region to be removed, if any, and note that there's no partial |
| * cluster to track |
| */ |
| if (sbi->s_cluster_ratio > 1) { |
| rc->first_do_lblk_found = false; |
| if (lblk > es->es_lblk) { |
| rc->left_es = es; |
| } else { |
| node = rb_prev(&es->rb_node); |
| rc->left_es = node ? rb_entry(node, |
| struct extent_status, |
| rb_node) : NULL; |
| } |
| rc->partial = false; |
| } |
| } |
| |
| /* |
| * count_rsvd - count the clusters containing delayed and not unwritten |
| * (delonly) blocks in a range within an extent and add to |
| * the running tally in rsvd_count |
| * |
| * @inode - file containing extent |
| * @lblk - first block in range |
| * @len - length of range in blocks |
| * @es - pointer to extent containing clusters to be counted |
| * @rc - pointer to reserved count data |
| * |
| * Tracks partial clusters found at the beginning and end of extents so |
| * they aren't overcounted when they span adjacent extents |
| */ |
| static void count_rsvd(struct inode *inode, ext4_lblk_t lblk, long len, |
| struct extent_status *es, struct rsvd_count *rc) |
| { |
| struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); |
| ext4_lblk_t i, end, nclu; |
| |
| if (!ext4_es_is_delonly(es)) |
| return; |
| |
| WARN_ON(len <= 0); |
| |
| if (sbi->s_cluster_ratio == 1) { |
| rc->ndelonly += (int) len; |
| return; |
| } |
| |
| /* bigalloc */ |
| |
| i = (lblk < es->es_lblk) ? es->es_lblk : lblk; |
| end = lblk + (ext4_lblk_t) len - 1; |
| end = (end > ext4_es_end(es)) ? ext4_es_end(es) : end; |
| |
| /* record the first block of the first delonly extent seen */ |
| if (rc->first_do_lblk_found == false) { |
| rc->first_do_lblk = i; |
| rc->first_do_lblk_found = true; |
| } |
| |
| /* update the last lblk in the region seen so far */ |
| rc->last_do_lblk = end; |
| |
| /* |
| * if we're tracking a partial cluster and the current extent |
| * doesn't start with it, count it and stop tracking |
| */ |
| if (rc->partial && (rc->lclu != EXT4_B2C(sbi, i))) { |
| rc->ndelonly++; |
| rc->partial = false; |
| } |
| |
| /* |
| * if the first cluster doesn't start on a cluster boundary but |
| * ends on one, count it |
| */ |
| if (EXT4_LBLK_COFF(sbi, i) != 0) { |
| if (end >= EXT4_LBLK_CFILL(sbi, i)) { |
| rc->ndelonly++; |
| rc->partial = false; |
| i = EXT4_LBLK_CFILL(sbi, i) + 1; |
| } |
| } |
| |
| /* |
| * if the current cluster starts on a cluster boundary, count the |
| * number of whole delonly clusters in the extent |
| */ |
| if ((i + sbi->s_cluster_ratio - 1) <= end) { |
| nclu = (end - i + 1) >> sbi->s_cluster_bits; |
| rc->ndelonly += nclu; |
| i += nclu << sbi->s_cluster_bits; |
| } |
| |
| /* |
| * start tracking a partial cluster if there's a partial at the end |
| * of the current extent and we're not already tracking one |
| */ |
| if (!rc->partial && i <= end) { |
| rc->partial = true; |
| rc->lclu = EXT4_B2C(sbi, i); |
| } |
| } |
| |
| /* |
| * __pr_tree_search - search for a pending cluster reservation |
| * |
| * @root - root of pending reservation tree |
| * @lclu - logical cluster to search for |
| * |
| * Returns the pending reservation for the cluster identified by @lclu |
| * if found. If not, returns a reservation for the next cluster if any, |
| * and if not, returns NULL. |
| */ |
| static struct pending_reservation *__pr_tree_search(struct rb_root *root, |
| ext4_lblk_t lclu) |
| { |
| struct rb_node *node = root->rb_node; |
| struct pending_reservation *pr = NULL; |
| |
| while (node) { |
| pr = rb_entry(node, struct pending_reservation, rb_node); |
| if (lclu < pr->lclu) |
| node = node->rb_left; |
| else if (lclu > pr->lclu) |
| node = node->rb_right; |
| else |
| return pr; |
| } |
| if (pr && lclu < pr->lclu) |
| return pr; |
| if (pr && lclu > pr->lclu) { |
| node = rb_next(&pr->rb_node); |
| return node ? rb_entry(node, struct pending_reservation, |
| rb_node) : NULL; |
| } |
| return NULL; |
| } |
| |
| /* |
| * get_rsvd - calculates and returns the number of cluster reservations to be |
| * released when removing a block range from the extent status tree |
| * and releases any pending reservations within the range |
| * |
| * @inode - file containing block range |
| * @end - last block in range |
| * @right_es - pointer to extent containing next block beyond end or NULL |
| * @rc - pointer to reserved count data |
| * |
| * The number of reservations to be released is equal to the number of |
| * clusters containing delayed and not unwritten (delonly) blocks within |
| * the range, minus the number of clusters still containing delonly blocks |
| * at the ends of the range, and minus the number of pending reservations |
| * within the range. |
| */ |
| static unsigned int get_rsvd(struct inode *inode, ext4_lblk_t end, |
| struct extent_status *right_es, |
| struct rsvd_count *rc) |
| { |
| struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); |
| struct pending_reservation *pr; |
| struct ext4_pending_tree *tree = &EXT4_I(inode)->i_pending_tree; |
| struct rb_node *node; |
| ext4_lblk_t first_lclu, last_lclu; |
| bool left_delonly, right_delonly, count_pending; |
| struct extent_status *es; |
| |
| if (sbi->s_cluster_ratio > 1) { |
| /* count any remaining partial cluster */ |
| if (rc->partial) |
| rc->ndelonly++; |
| |
| if (rc->ndelonly == 0) |
| return 0; |
| |
| first_lclu = EXT4_B2C(sbi, rc->first_do_lblk); |
| last_lclu = EXT4_B2C(sbi, rc->last_do_lblk); |
| |
| /* |
| * decrease the delonly count by the number of clusters at the |
| * ends of the range that still contain delonly blocks - |
| * these clusters still need to be reserved |
| */ |
| left_delonly = right_delonly = false; |
| |
| es = rc->left_es; |
| while (es && ext4_es_end(es) >= |
| EXT4_LBLK_CMASK(sbi, rc->first_do_lblk)) { |
| if (ext4_es_is_delonly(es)) { |
| rc->ndelonly--; |
| left_delonly = true; |
| break; |
| } |
| node = rb_prev(&es->rb_node); |
| if (!node) |
| break; |
| es = rb_entry(node, struct extent_status, rb_node); |
| } |
| if (right_es && (!left_delonly || first_lclu != last_lclu)) { |
| if (end < ext4_es_end(right_es)) { |
| es = right_es; |
| } else { |
| node = rb_next(&right_es->rb_node); |
| es = node ? rb_entry(node, struct extent_status, |
| rb_node) : NULL; |
| } |
| while (es && es->es_lblk <= |
| EXT4_LBLK_CFILL(sbi, rc->last_do_lblk)) { |
| if (ext4_es_is_delonly(es)) { |
| rc->ndelonly--; |
| right_delonly = true; |
| break; |
| } |
| node = rb_next(&es->rb_node); |
| if (!node) |
| break; |
| es = rb_entry(node, struct extent_status, |
| rb_node); |
| } |
| } |
| |
| /* |
| * Determine the block range that should be searched for |
| * pending reservations, if any. Clusters on the ends of the |
| * original removed range containing delonly blocks are |
| * excluded. They've already been accounted for and it's not |
| * possible to determine if an associated pending reservation |
| * should be released with the information available in the |
| * extents status tree. |
| */ |
| if (first_lclu == last_lclu) { |
| if (left_delonly | right_delonly) |
| count_pending = false; |
| else |
| count_pending = true; |
| } else { |
| if (left_delonly) |
| first_lclu++; |
| if (right_delonly) |
| last_lclu--; |
| if (first_lclu <= last_lclu) |
| count_pending = true; |
| else |
| count_pending = false; |
| } |
| |
| /* |
| * a pending reservation found between first_lclu and last_lclu |
| * represents an allocated cluster that contained at least one |
| * delonly block, so the delonly total must be reduced by one |
| * for each pending reservation found and released |
| */ |
| if (count_pending) { |
| pr = __pr_tree_search(&tree->root, first_lclu); |
| while (pr && pr->lclu <= last_lclu) { |
| rc->ndelonly--; |
| node = rb_next(&pr->rb_node); |
| rb_erase(&pr->rb_node, &tree->root); |
| kmem_cache_free(ext4_pending_cachep, pr); |
| if (!node) |
| break; |
| pr = rb_entry(node, struct pending_reservation, |
| rb_node); |
| } |
| } |
| } |
| return rc->ndelonly; |
| } |
| |
| |
| /* |
| * __es_remove_extent - removes block range from extent status tree |
| * |
| * @inode - file containing range |
| * @lblk - first block in range |
| * @end - last block in range |
| * @reserved - number of cluster reservations released |
| * |
| * If @reserved is not NULL and delayed allocation is enabled, counts |
| * block/cluster reservations freed by removing range and if bigalloc |
| * enabled cancels pending reservations as needed. Returns 0 on success, |
| * error code on failure. |
| */ |
| static int __es_remove_extent(struct inode *inode, ext4_lblk_t lblk, |
| ext4_lblk_t end, int *reserved) |
| { |
| struct ext4_es_tree *tree = &EXT4_I(inode)->i_es_tree; |
| struct rb_node *node; |
| struct extent_status *es; |
| struct extent_status orig_es; |
| ext4_lblk_t len1, len2; |
| ext4_fsblk_t block; |
| int err; |
| bool count_reserved = true; |
| struct rsvd_count rc; |
| |
| if (reserved == NULL || !test_opt(inode->i_sb, DELALLOC)) |
| count_reserved = false; |
| retry: |
| err = 0; |
| |
| es = __es_tree_search(&tree->root, lblk); |
| if (!es) |
| goto out; |
| if (es->es_lblk > end) |
| goto out; |
| |
| /* Simply invalidate cache_es. */ |
| tree->cache_es = NULL; |
| if (count_reserved) |
| init_rsvd(inode, lblk, es, &rc); |
| |
| orig_es.es_lblk = es->es_lblk; |
| orig_es.es_len = es->es_len; |
| orig_es.es_pblk = es->es_pblk; |
| |
| len1 = lblk > es->es_lblk ? lblk - es->es_lblk : 0; |
| len2 = ext4_es_end(es) > end ? ext4_es_end(es) - end : 0; |
| if (len1 > 0) |
| es->es_len = len1; |
| if (len2 > 0) { |
| if (len1 > 0) { |
| struct extent_status newes; |
| |
| newes.es_lblk = end + 1; |
| newes.es_len = len2; |
| block = 0x7FDEADBEEFULL; |
| if (ext4_es_is_written(&orig_es) || |
| ext4_es_is_unwritten(&orig_es)) |
| block = ext4_es_pblock(&orig_es) + |
| orig_es.es_len - len2; |
| ext4_es_store_pblock_status(&newes, block, |
| ext4_es_status(&orig_es)); |
| err = __es_insert_extent(inode, &newes); |
| if (err) { |
| es->es_lblk = orig_es.es_lblk; |
| es->es_len = orig_es.es_len; |
| if ((err == -ENOMEM) && |
| __es_shrink(EXT4_SB(inode->i_sb), |
| 128, EXT4_I(inode))) |
| goto retry; |
| goto out; |
| } |
| } else { |
| es->es_lblk = end + 1; |
| es->es_len = len2; |
| if (ext4_es_is_written(es) || |
| ext4_es_is_unwritten(es)) { |
| block = orig_es.es_pblk + orig_es.es_len - len2; |
| ext4_es_store_pblock(es, block); |
| } |
| } |
| if (count_reserved) |
| count_rsvd(inode, lblk, orig_es.es_len - len1 - len2, |
| &orig_es, &rc); |
| goto out; |
| } |
| |
| if (len1 > 0) { |
| if (count_reserved) |
| count_rsvd(inode, lblk, orig_es.es_len - len1, |
| &orig_es, &rc); |
| node = rb_next(&es->rb_node); |
| if (node) |
| es = rb_entry(node, struct extent_status, rb_node); |
| else |
| es = NULL; |
| } |
| |
| while (es && ext4_es_end(es) <= end) { |
| if (count_reserved) |
| count_rsvd(inode, es->es_lblk, es->es_len, es, &rc); |
| node = rb_next(&es->rb_node); |
| rb_erase(&es->rb_node, &tree->root); |
| ext4_es_free_extent(inode, es); |
| if (!node) { |
| es = NULL; |
| break; |
| } |
| es = rb_entry(node, struct extent_status, rb_node); |
| } |
| |
| if (es && es->es_lblk < end + 1) { |
| ext4_lblk_t orig_len = es->es_len; |
| |
| len1 = ext4_es_end(es) - end; |
| if (count_reserved) |
| count_rsvd(inode, es->es_lblk, orig_len - len1, |
| es, &rc); |
| es->es_lblk = end + 1; |
| es->es_len = len1; |
| if (ext4_es_is_written(es) || ext4_es_is_unwritten(es)) { |
| block = es->es_pblk + orig_len - len1; |
| ext4_es_store_pblock(es, block); |
| } |
| } |
| |
| if (count_reserved) |
| *reserved = get_rsvd(inode, end, es, &rc); |
| out: |
| return err; |
| } |
| |
| /* |
| * ext4_es_remove_extent - removes block range from extent status tree |
| * |
| * @inode - file containing range |
| * @lblk - first block in range |
| * @len - number of blocks to remove |
| * |
| * Reduces block/cluster reservation count and for bigalloc cancels pending |
| * reservations as needed. Returns 0 on success, error code on failure. |
| */ |
| int ext4_es_remove_extent(struct inode *inode, ext4_lblk_t lblk, |
| ext4_lblk_t len) |
| { |
| ext4_lblk_t end; |
| int err = 0; |
| int reserved = 0; |
| |
| trace_ext4_es_remove_extent(inode, lblk, len); |
| es_debug("remove [%u/%u) from extent status tree of inode %lu\n", |
| lblk, len, inode->i_ino); |
| |
| if (!len) |
| return err; |
| |
| end = lblk + len - 1; |
| BUG_ON(end < lblk); |
| |
| /* |
| * ext4_clear_inode() depends on us taking i_es_lock unconditionally |
| * so that we are sure __es_shrink() is done with the inode before it |
| * is reclaimed. |
| */ |
| write_lock(&EXT4_I(inode)->i_es_lock); |
| err = __es_remove_extent(inode, lblk, end, &reserved); |
| write_unlock(&EXT4_I(inode)->i_es_lock); |
| ext4_es_print_tree(inode); |
| ext4_da_release_space(inode, reserved); |
| return err; |
| } |
| |
| static int __es_shrink(struct ext4_sb_info *sbi, int nr_to_scan, |
| struct ext4_inode_info *locked_ei) |
| { |
| struct ext4_inode_info *ei; |
| struct ext4_es_stats *es_stats; |
| ktime_t start_time; |
| u64 scan_time; |
| int nr_to_walk; |
| int nr_shrunk = 0; |
| int retried = 0, nr_skipped = 0; |
| |
| es_stats = &sbi->s_es_stats; |
| start_time = ktime_get(); |
| |
| retry: |
| spin_lock(&sbi->s_es_lock); |
| nr_to_walk = sbi->s_es_nr_inode; |
| while (nr_to_walk-- > 0) { |
| if (list_empty(&sbi->s_es_list)) { |
| spin_unlock(&sbi->s_es_lock); |
| goto out; |
| } |
| ei = list_first_entry(&sbi->s_es_list, struct ext4_inode_info, |
| i_es_list); |
| /* Move the inode to the tail */ |
| list_move_tail(&ei->i_es_list, &sbi->s_es_list); |
| |
| /* |
| * Normally we try hard to avoid shrinking precached inodes, |
| * but we will as a last resort. |
| */ |
| if (!retried && ext4_test_inode_state(&ei->vfs_inode, |
| EXT4_STATE_EXT_PRECACHED)) { |
| nr_skipped++; |
| continue; |
| } |
| |
| if (ei == locked_ei || !write_trylock(&ei->i_es_lock)) { |
| nr_skipped++; |
| continue; |
| } |
| /* |
| * Now we hold i_es_lock which protects us from inode reclaim |
| * freeing inode under us |
| */ |
| spin_unlock(&sbi->s_es_lock); |
| |
| nr_shrunk += es_reclaim_extents(ei, &nr_to_scan); |
| write_unlock(&ei->i_es_lock); |
| |
| if (nr_to_scan <= 0) |
| goto out; |
| spin_lock(&sbi->s_es_lock); |
| } |
| spin_unlock(&sbi->s_es_lock); |
| |
| /* |
| * If we skipped any inodes, and we weren't able to make any |
| * forward progress, try again to scan precached inodes. |
| */ |
| if ((nr_shrunk == 0) && nr_skipped && !retried) { |
| retried++; |
| goto retry; |
| } |
| |
| if (locked_ei && nr_shrunk == 0) |
| nr_shrunk = es_reclaim_extents(locked_ei, &nr_to_scan); |
| |
| out: |
| scan_time = ktime_to_ns(ktime_sub(ktime_get(), start_time)); |
| if (likely(es_stats->es_stats_scan_time)) |
| es_stats->es_stats_scan_time = (scan_time + |
| es_stats->es_stats_scan_time*3) / 4; |
| else |
| es_stats->es_stats_scan_time = scan_time; |
| if (scan_time > es_stats->es_stats_max_scan_time) |
| es_stats->es_stats_max_scan_time = scan_time; |
| if (likely(es_stats->es_stats_shrunk)) |
| es_stats->es_stats_shrunk = (nr_shrunk + |
| es_stats->es_stats_shrunk*3) / 4; |
| else |
| es_stats->es_stats_shrunk = nr_shrunk; |
| |
| trace_ext4_es_shrink(sbi->s_sb, nr_shrunk, scan_time, |
| nr_skipped, retried); |
| return nr_shrunk; |
| } |
| |
| static unsigned long ext4_es_count(struct shrinker *shrink, |
| struct shrink_control *sc) |
| { |
| unsigned long nr; |
| struct ext4_sb_info *sbi; |
| |
| sbi = container_of(shrink, struct ext4_sb_info, s_es_shrinker); |
| nr = percpu_counter_read_positive(&sbi->s_es_stats.es_stats_shk_cnt); |
| trace_ext4_es_shrink_count(sbi->s_sb, sc->nr_to_scan, nr); |
| return nr; |
| } |
| |
| static unsigned long ext4_es_scan(struct shrinker *shrink, |
| struct shrink_control *sc) |
| { |
| struct ext4_sb_info *sbi = container_of(shrink, |
| struct ext4_sb_info, s_es_shrinker); |
| int nr_to_scan = sc->nr_to_scan; |
| int ret, nr_shrunk; |
| |
| ret = percpu_counter_read_positive(&sbi->s_es_stats.es_stats_shk_cnt); |
| trace_ext4_es_shrink_scan_enter(sbi->s_sb, nr_to_scan, ret); |
| |
| nr_shrunk = __es_shrink(sbi, nr_to_scan, NULL); |
| |
| ret = percpu_counter_read_positive(&sbi->s_es_stats.es_stats_shk_cnt); |
| trace_ext4_es_shrink_scan_exit(sbi->s_sb, nr_shrunk, ret); |
| return nr_shrunk; |
| } |
| |
| int ext4_seq_es_shrinker_info_show(struct seq_file *seq, void *v) |
| { |
| struct ext4_sb_info *sbi = EXT4_SB((struct super_block *) seq->private); |
| struct ext4_es_stats *es_stats = &sbi->s_es_stats; |
| struct ext4_inode_info *ei, *max = NULL; |
| unsigned int inode_cnt = 0; |
| |
| if (v != SEQ_START_TOKEN) |
| return 0; |
| |
| /* here we just find an inode that has the max nr. of objects */ |
| spin_lock(&sbi->s_es_lock); |
| list_for_each_entry(ei, &sbi->s_es_list, i_es_list) { |
| inode_cnt++; |
| if (max && max->i_es_all_nr < ei->i_es_all_nr) |
| max = ei; |
| else if (!max) |
| max = ei; |
| } |
| spin_unlock(&sbi->s_es_lock); |
| |
| seq_printf(seq, "stats:\n %lld objects\n %lld reclaimable objects\n", |
| percpu_counter_sum_positive(&es_stats->es_stats_all_cnt), |
| percpu_counter_sum_positive(&es_stats->es_stats_shk_cnt)); |
| seq_printf(seq, " %lld/%lld cache hits/misses\n", |
| percpu_counter_sum_positive(&es_stats->es_stats_cache_hits), |
| percpu_counter_sum_positive(&es_stats->es_stats_cache_misses)); |
| if (inode_cnt) |
| seq_printf(seq, " %d inodes on list\n", inode_cnt); |
| |
| seq_printf(seq, "average:\n %llu us scan time\n", |
| div_u64(es_stats->es_stats_scan_time, 1000)); |
| seq_printf(seq, " %lu shrunk objects\n", es_stats->es_stats_shrunk); |
| if (inode_cnt) |
| seq_printf(seq, |
| "maximum:\n %lu inode (%u objects, %u reclaimable)\n" |
| " %llu us max scan time\n", |
| max->vfs_inode.i_ino, max->i_es_all_nr, max->i_es_shk_nr, |
| div_u64(es_stats->es_stats_max_scan_time, 1000)); |
| |
| return 0; |
| } |
| |
| int ext4_es_register_shrinker(struct ext4_sb_info *sbi) |
| { |
| int err; |
| |
| /* Make sure we have enough bits for physical block number */ |
| BUILD_BUG_ON(ES_SHIFT < 48); |
| INIT_LIST_HEAD(&sbi->s_es_list); |
| sbi->s_es_nr_inode = 0; |
| spin_lock_init(&sbi->s_es_lock); |
| sbi->s_es_stats.es_stats_shrunk = 0; |
| err = percpu_counter_init(&sbi->s_es_stats.es_stats_cache_hits, 0, |
| GFP_KERNEL); |
| if (err) |
| return err; |
| err = percpu_counter_init(&sbi->s_es_stats.es_stats_cache_misses, 0, |
| GFP_KERNEL); |
| if (err) |
| goto err1; |
| sbi->s_es_stats.es_stats_scan_time = 0; |
| sbi->s_es_stats.es_stats_max_scan_time = 0; |
| err = percpu_counter_init(&sbi->s_es_stats.es_stats_all_cnt, 0, GFP_KERNEL); |
| if (err) |
| goto err2; |
| err = percpu_counter_init(&sbi->s_es_stats.es_stats_shk_cnt, 0, GFP_KERNEL); |
| if (err) |
| goto err3; |
| |
| sbi->s_es_shrinker.scan_objects = ext4_es_scan; |
| sbi->s_es_shrinker.count_objects = ext4_es_count; |
| sbi->s_es_shrinker.seeks = DEFAULT_SEEKS; |
| err = register_shrinker(&sbi->s_es_shrinker); |
| if (err) |
| goto err4; |
| |
| return 0; |
| err4: |
| percpu_counter_destroy(&sbi->s_es_stats.es_stats_shk_cnt); |
| err3: |
| percpu_counter_destroy(&sbi->s_es_stats.es_stats_all_cnt); |
| err2: |
| percpu_counter_destroy(&sbi->s_es_stats.es_stats_cache_misses); |
| err1: |
| percpu_counter_destroy(&sbi->s_es_stats.es_stats_cache_hits); |
| return err; |
| } |
| |
| void ext4_es_unregister_shrinker(struct ext4_sb_info *sbi) |
| { |
| percpu_counter_destroy(&sbi->s_es_stats.es_stats_cache_hits); |
| percpu_counter_destroy(&sbi->s_es_stats.es_stats_cache_misses); |
| percpu_counter_destroy(&sbi->s_es_stats.es_stats_all_cnt); |
| percpu_counter_destroy(&sbi->s_es_stats.es_stats_shk_cnt); |
| unregister_shrinker(&sbi->s_es_shrinker); |
| } |
| |
| /* |
| * Shrink extents in given inode from ei->i_es_shrink_lblk till end. Scan at |
| * most *nr_to_scan extents, update *nr_to_scan accordingly. |
| * |
| * Return 0 if we hit end of tree / interval, 1 if we exhausted nr_to_scan. |
| * Increment *nr_shrunk by the number of reclaimed extents. Also update |
| * ei->i_es_shrink_lblk to where we should continue scanning. |
| */ |
| static int es_do_reclaim_extents(struct ext4_inode_info *ei, ext4_lblk_t end, |
| int *nr_to_scan, int *nr_shrunk) |
| { |
| struct inode *inode = &ei->vfs_inode; |
| struct ext4_es_tree *tree = &ei->i_es_tree; |
| struct extent_status *es; |
| struct rb_node *node; |
| |
| es = __es_tree_search(&tree->root, ei->i_es_shrink_lblk); |
| if (!es) |
| goto out_wrap; |
| |
| while (*nr_to_scan > 0) { |
| if (es->es_lblk > end) { |
| ei->i_es_shrink_lblk = end + 1; |
| return 0; |
| } |
| |
| (*nr_to_scan)--; |
| node = rb_next(&es->rb_node); |
| /* |
| * We can't reclaim delayed extent from status tree because |
| * fiemap, bigallic, and seek_data/hole need to use it. |
| */ |
| if (ext4_es_is_delayed(es)) |
| goto next; |
| if (ext4_es_is_referenced(es)) { |
| ext4_es_clear_referenced(es); |
| goto next; |
| } |
| |
| rb_erase(&es->rb_node, &tree->root); |
| ext4_es_free_extent(inode, es); |
| (*nr_shrunk)++; |
| next: |
| if (!node) |
| goto out_wrap; |
| es = rb_entry(node, struct extent_status, rb_node); |
| } |
| ei->i_es_shrink_lblk = es->es_lblk; |
| return 1; |
| out_wrap: |
| ei->i_es_shrink_lblk = 0; |
| return 0; |
| } |
| |
| static int es_reclaim_extents(struct ext4_inode_info *ei, int *nr_to_scan) |
| { |
| struct inode *inode = &ei->vfs_inode; |
| int nr_shrunk = 0; |
| ext4_lblk_t start = ei->i_es_shrink_lblk; |
| static DEFINE_RATELIMIT_STATE(_rs, DEFAULT_RATELIMIT_INTERVAL, |
| DEFAULT_RATELIMIT_BURST); |
| |
| if (ei->i_es_shk_nr == 0) |
| return 0; |
| |
| if (ext4_test_inode_state(inode, EXT4_STATE_EXT_PRECACHED) && |
| __ratelimit(&_rs)) |
| ext4_warning(inode->i_sb, "forced shrink of precached extents"); |
| |
| if (!es_do_reclaim_extents(ei, EXT_MAX_BLOCKS, nr_to_scan, &nr_shrunk) && |
| start != 0) |
| es_do_reclaim_extents(ei, start - 1, nr_to_scan, &nr_shrunk); |
| |
| ei->i_es_tree.cache_es = NULL; |
| return nr_shrunk; |
| } |
| |
| /* |
| * Called to support EXT4_IOC_CLEAR_ES_CACHE. We can only remove |
| * discretionary entries from the extent status cache. (Some entries |
| * must be present for proper operations.) |
| */ |
| void ext4_clear_inode_es(struct inode *inode) |
| { |
| struct ext4_inode_info *ei = EXT4_I(inode); |
| struct extent_status *es; |
| struct ext4_es_tree *tree; |
| struct rb_node *node; |
| |
| write_lock(&ei->i_es_lock); |
| tree = &EXT4_I(inode)->i_es_tree; |
| tree->cache_es = NULL; |
| node = rb_first(&tree->root); |
| while (node) { |
| es = rb_entry(node, struct extent_status, rb_node); |
| node = rb_next(node); |
| if (!ext4_es_is_delayed(es)) { |
| rb_erase(&es->rb_node, &tree->root); |
| ext4_es_free_extent(inode, es); |
| } |
| } |
| ext4_clear_inode_state(inode, EXT4_STATE_EXT_PRECACHED); |
| write_unlock(&ei->i_es_lock); |
| } |
| |
| #ifdef ES_DEBUG__ |
| static void ext4_print_pending_tree(struct inode *inode) |
| { |
| struct ext4_pending_tree *tree; |
| struct rb_node *node; |
| struct pending_reservation *pr; |
| |
| printk(KERN_DEBUG "pending reservations for inode %lu:", inode->i_ino); |
| tree = &EXT4_I(inode)->i_pending_tree; |
| node = rb_first(&tree->root); |
| while (node) { |
| pr = rb_entry(node, struct pending_reservation, rb_node); |
| printk(KERN_DEBUG " %u", pr->lclu); |
| node = rb_next(node); |
| } |
| printk(KERN_DEBUG "\n"); |
| } |
| #else |
| #define ext4_print_pending_tree(inode) |
| #endif |
| |
| int __init ext4_init_pending(void) |
| { |
| ext4_pending_cachep = kmem_cache_create("ext4_pending_reservation", |
| sizeof(struct pending_reservation), |
| 0, (SLAB_RECLAIM_ACCOUNT), NULL); |
| if (ext4_pending_cachep == NULL) |
| return -ENOMEM; |
| return 0; |
| } |
| |
| void ext4_exit_pending(void) |
| { |
| kmem_cache_destroy(ext4_pending_cachep); |
| } |
| |
| void ext4_init_pending_tree(struct ext4_pending_tree *tree) |
| { |
| tree->root = RB_ROOT; |
| } |
| |
| /* |
| * __get_pending - retrieve a pointer to a pending reservation |
| * |
| * @inode - file containing the pending cluster reservation |
| * @lclu - logical cluster of interest |
| * |
| * Returns a pointer to a pending reservation if it's a member of |
| * the set, and NULL if not. Must be called holding i_es_lock. |
| */ |
| static struct pending_reservation *__get_pending(struct inode *inode, |
| ext4_lblk_t lclu) |
| { |
| struct ext4_pending_tree *tree; |
| struct rb_node *node; |
| struct pending_reservation *pr = NULL; |
| |
| tree = &EXT4_I(inode)->i_pending_tree; |
| node = (&tree->root)->rb_node; |
| |
| while (node) { |
| pr = rb_entry(node, struct pending_reservation, rb_node); |
| if (lclu < pr->lclu) |
| node = node->rb_left; |
| else if (lclu > pr->lclu) |
| node = node->rb_right; |
| else if (lclu == pr->lclu) |
| return pr; |
| } |
| return NULL; |
| } |
| |
| /* |
| * __insert_pending - adds a pending cluster reservation to the set of |
| * pending reservations |
| * |
| * @inode - file containing the cluster |
| * @lblk - logical block in the cluster to be added |
| * |
| * Returns 0 on successful insertion and -ENOMEM on failure. If the |
| * pending reservation is already in the set, returns successfully. |
| */ |
| static int __insert_pending(struct inode *inode, ext4_lblk_t lblk) |
| { |
| struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); |
| struct ext4_pending_tree *tree = &EXT4_I(inode)->i_pending_tree; |
| struct rb_node **p = &tree->root.rb_node; |
| struct rb_node *parent = NULL; |
| struct pending_reservation *pr; |
| ext4_lblk_t lclu; |
| int ret = 0; |
| |
| lclu = EXT4_B2C(sbi, lblk); |
| /* search to find parent for insertion */ |
| while (*p) { |
| parent = *p; |
| pr = rb_entry(parent, struct pending_reservation, rb_node); |
| |
| if (lclu < pr->lclu) { |
| p = &(*p)->rb_left; |
| } else if (lclu > pr->lclu) { |
| p = &(*p)->rb_right; |
| } else { |
| /* pending reservation already inserted */ |
| goto out; |
| } |
| } |
| |
| pr = kmem_cache_alloc(ext4_pending_cachep, GFP_ATOMIC); |
| if (pr == NULL) { |
| ret = -ENOMEM; |
| goto out; |
| } |
| pr->lclu = lclu; |
| |
| rb_link_node(&pr->rb_node, parent, p); |
| rb_insert_color(&pr->rb_node, &tree->root); |
| |
| out: |
| return ret; |
| } |
| |
| /* |
| * __remove_pending - removes a pending cluster reservation from the set |
| * of pending reservations |
| * |
| * @inode - file containing the cluster |
| * @lblk - logical block in the pending cluster reservation to be removed |
| * |
| * Returns successfully if pending reservation is not a member of the set. |
| */ |
| static void __remove_pending(struct inode *inode, ext4_lblk_t lblk) |
| { |
| struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); |
| struct pending_reservation *pr; |
| struct ext4_pending_tree *tree; |
| |
| pr = __get_pending(inode, EXT4_B2C(sbi, lblk)); |
| if (pr != NULL) { |
| tree = &EXT4_I(inode)->i_pending_tree; |
| rb_erase(&pr->rb_node, &tree->root); |
| kmem_cache_free(ext4_pending_cachep, pr); |
| } |
| } |
| |
| /* |
| * ext4_remove_pending - removes a pending cluster reservation from the set |
| * of pending reservations |
| * |
| * @inode - file containing the cluster |
| * @lblk - logical block in the pending cluster reservation to be removed |
| * |
| * Locking for external use of __remove_pending. |
| */ |
| void ext4_remove_pending(struct inode *inode, ext4_lblk_t lblk) |
| { |
| struct ext4_inode_info *ei = EXT4_I(inode); |
| |
| write_lock(&ei->i_es_lock); |
| __remove_pending(inode, lblk); |
| write_unlock(&ei->i_es_lock); |
| } |
| |
| /* |
| * ext4_is_pending - determine whether a cluster has a pending reservation |
| * on it |
| * |
| * @inode - file containing the cluster |
| * @lblk - logical block in the cluster |
| * |
| * Returns true if there's a pending reservation for the cluster in the |
| * set of pending reservations, and false if not. |
| */ |
| bool ext4_is_pending(struct inode *inode, ext4_lblk_t lblk) |
| { |
| struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); |
| struct ext4_inode_info *ei = EXT4_I(inode); |
| bool ret; |
| |
| read_lock(&ei->i_es_lock); |
| ret = (bool)(__get_pending(inode, EXT4_B2C(sbi, lblk)) != NULL); |
| read_unlock(&ei->i_es_lock); |
| |
| return ret; |
| } |
| |
| /* |
| * ext4_es_insert_delayed_block - adds a delayed block to the extents status |
| * tree, adding a pending reservation where |
| * needed |
| * |
| * @inode - file containing the newly added block |
| * @lblk - logical block to be added |
| * @allocated - indicates whether a physical cluster has been allocated for |
| * the logical cluster that contains the block |
| * |
| * Returns 0 on success, negative error code on failure. |
| */ |
| int ext4_es_insert_delayed_block(struct inode *inode, ext4_lblk_t lblk, |
| bool allocated) |
| { |
| struct extent_status newes; |
| int err = 0; |
| |
| es_debug("add [%u/1) delayed to extent status tree of inode %lu\n", |
| lblk, inode->i_ino); |
| |
| newes.es_lblk = lblk; |
| newes.es_len = 1; |
| ext4_es_store_pblock_status(&newes, ~0, EXTENT_STATUS_DELAYED); |
| trace_ext4_es_insert_delayed_block(inode, &newes, allocated); |
| |
| ext4_es_insert_extent_check(inode, &newes); |
| |
| write_lock(&EXT4_I(inode)->i_es_lock); |
| |
| err = __es_remove_extent(inode, lblk, lblk, NULL); |
| if (err != 0) |
| goto error; |
| retry: |
| err = __es_insert_extent(inode, &newes); |
| if (err == -ENOMEM && __es_shrink(EXT4_SB(inode->i_sb), |
| 128, EXT4_I(inode))) |
| goto retry; |
| if (err != 0) |
| goto error; |
| |
| if (allocated) |
| __insert_pending(inode, lblk); |
| |
| error: |
| write_unlock(&EXT4_I(inode)->i_es_lock); |
| |
| ext4_es_print_tree(inode); |
| ext4_print_pending_tree(inode); |
| |
| return err; |
| } |
| |
| /* |
| * __es_delayed_clu - count number of clusters containing blocks that |
| * are delayed only |
| * |
| * @inode - file containing block range |
| * @start - logical block defining start of range |
| * @end - logical block defining end of range |
| * |
| * Returns the number of clusters containing only delayed (not delayed |
| * and unwritten) blocks in the range specified by @start and @end. Any |
| * cluster or part of a cluster within the range and containing a delayed |
| * and not unwritten block within the range is counted as a whole cluster. |
| */ |
| static unsigned int __es_delayed_clu(struct inode *inode, ext4_lblk_t start, |
| ext4_lblk_t end) |
| { |
| struct ext4_es_tree *tree = &EXT4_I(inode)->i_es_tree; |
| struct extent_status *es; |
| struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); |
| struct rb_node *node; |
| ext4_lblk_t first_lclu, last_lclu; |
| unsigned long long last_counted_lclu; |
| unsigned int n = 0; |
| |
| /* guaranteed to be unequal to any ext4_lblk_t value */ |
| last_counted_lclu = ~0ULL; |
| |
| es = __es_tree_search(&tree->root, start); |
| |
| while (es && (es->es_lblk <= end)) { |
| if (ext4_es_is_delonly(es)) { |
| if (es->es_lblk <= start) |
| first_lclu = EXT4_B2C(sbi, start); |
| else |
| first_lclu = EXT4_B2C(sbi, es->es_lblk); |
| |
| if (ext4_es_end(es) >= end) |
| last_lclu = EXT4_B2C(sbi, end); |
| else |
| last_lclu = EXT4_B2C(sbi, ext4_es_end(es)); |
| |
| if (first_lclu == last_counted_lclu) |
| n += last_lclu - first_lclu; |
| else |
| n += last_lclu - first_lclu + 1; |
| last_counted_lclu = last_lclu; |
| } |
| node = rb_next(&es->rb_node); |
| if (!node) |
| break; |
| es = rb_entry(node, struct extent_status, rb_node); |
| } |
| |
| return n; |
| } |
| |
| /* |
| * ext4_es_delayed_clu - count number of clusters containing blocks that |
| * are both delayed and unwritten |
| * |
| * @inode - file containing block range |
| * @lblk - logical block defining start of range |
| * @len - number of blocks in range |
| * |
| * Locking for external use of __es_delayed_clu(). |
| */ |
| unsigned int ext4_es_delayed_clu(struct inode *inode, ext4_lblk_t lblk, |
| ext4_lblk_t len) |
| { |
| struct ext4_inode_info *ei = EXT4_I(inode); |
| ext4_lblk_t end; |
| unsigned int n; |
| |
| if (len == 0) |
| return 0; |
| |
| end = lblk + len - 1; |
| WARN_ON(end < lblk); |
| |
| read_lock(&ei->i_es_lock); |
| |
| n = __es_delayed_clu(inode, lblk, end); |
| |
| read_unlock(&ei->i_es_lock); |
| |
| return n; |
| } |
| |
| /* |
| * __revise_pending - makes, cancels, or leaves unchanged pending cluster |
| * reservations for a specified block range depending |
| * upon the presence or absence of delayed blocks |
| * outside the range within clusters at the ends of the |
| * range |
| * |
| * @inode - file containing the range |
| * @lblk - logical block defining the start of range |
| * @len - length of range in blocks |
| * |
| * Used after a newly allocated extent is added to the extents status tree. |
| * Requires that the extents in the range have either written or unwritten |
| * status. Must be called while holding i_es_lock. |
| */ |
| static void __revise_pending(struct inode *inode, ext4_lblk_t lblk, |
| ext4_lblk_t len) |
| { |
| struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); |
| ext4_lblk_t end = lblk + len - 1; |
| ext4_lblk_t first, last; |
| bool f_del = false, l_del = false; |
| |
| if (len == 0) |
| return; |
| |
| /* |
| * Two cases - block range within single cluster and block range |
| * spanning two or more clusters. Note that a cluster belonging |
| * to a range starting and/or ending on a cluster boundary is treated |
| * as if it does not contain a delayed extent. The new range may |
| * have allocated space for previously delayed blocks out to the |
| * cluster boundary, requiring that any pre-existing pending |
| * reservation be canceled. Because this code only looks at blocks |
| * outside the range, it should revise pending reservations |
| * correctly even if the extent represented by the range can't be |
| * inserted in the extents status tree due to ENOSPC. |
| */ |
| |
| if (EXT4_B2C(sbi, lblk) == EXT4_B2C(sbi, end)) { |
| first = EXT4_LBLK_CMASK(sbi, lblk); |
| if (first != lblk) |
| f_del = __es_scan_range(inode, &ext4_es_is_delonly, |
| first, lblk - 1); |
| if (f_del) { |
| __insert_pending(inode, first); |
| } else { |
| last = EXT4_LBLK_CMASK(sbi, end) + |
| sbi->s_cluster_ratio - 1; |
| if (last != end) |
| l_del = __es_scan_range(inode, |
| &ext4_es_is_delonly, |
| end + 1, last); |
| if (l_del) |
| __insert_pending(inode, last); |
| else |
| __remove_pending(inode, last); |
| } |
| } else { |
| first = EXT4_LBLK_CMASK(sbi, lblk); |
| if (first != lblk) |
| f_del = __es_scan_range(inode, &ext4_es_is_delonly, |
| first, lblk - 1); |
| if (f_del) |
| __insert_pending(inode, first); |
| else |
| __remove_pending(inode, first); |
| |
| last = EXT4_LBLK_CMASK(sbi, end) + sbi->s_cluster_ratio - 1; |
| if (last != end) |
| l_del = __es_scan_range(inode, &ext4_es_is_delonly, |
| end + 1, last); |
| if (l_del) |
| __insert_pending(inode, last); |
| else |
| __remove_pending(inode, last); |
| } |
| } |