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1// SPDX-License-Identifier: GPL-2.02/*3 * fs/ext4/mballoc.h4 *5 * Written by: Alex Tomas <alex@clusterfs.com>6 *7 */8#ifndef _EXT4_MBALLOC_H9#define _EXT4_MBALLOC_H10 11#include <linux/time.h>12#include <linux/fs.h>13#include <linux/namei.h>14#include <linux/quotaops.h>15#include <linux/buffer_head.h>16#include <linux/module.h>17#include <linux/swap.h>18#include <linux/proc_fs.h>19#include <linux/pagemap.h>20#include <linux/seq_file.h>21#include <linux/blkdev.h>22#include <linux/mutex.h>23#include "ext4_jbd2.h"24#include "ext4.h"25 26/*27 * mb_debug() dynamic printk msgs could be used to debug mballoc code.28 */29#ifdef CONFIG_EXT4_DEBUG30#define mb_debug(sb, fmt, ...) \31 pr_debug("[%s/%d] EXT4-fs (%s): (%s, %d): %s: " fmt, \32 current->comm, task_pid_nr(current), sb->s_id, \33 __FILE__, __LINE__, __func__, ##__VA_ARGS__)34#else35#define mb_debug(sb, fmt, ...) no_printk(fmt, ##__VA_ARGS__)36#endif37 38#define EXT4_MB_HISTORY_ALLOC 1 /* allocation */39#define EXT4_MB_HISTORY_PREALLOC 2 /* preallocated blocks used */40 41/*42 * How long mballoc can look for a best extent (in found extents)43 */44#define MB_DEFAULT_MAX_TO_SCAN 20045 46/*47 * How long mballoc must look for a best extent48 */49#define MB_DEFAULT_MIN_TO_SCAN 1050 51/*52 * with 's_mb_stats' allocator will collect stats that will be53 * shown at umount. The collecting costs though!54 */55#define MB_DEFAULT_STATS 056 57/*58 * files smaller than MB_DEFAULT_STREAM_THRESHOLD are served59 * by the stream allocator, which purpose is to pack requests60 * as close each to other as possible to produce smooth I/O traffic61 * We use locality group prealloc space for stream request.62 * We can tune the same via /proc/fs/ext4/<partition>/stream_req63 */64#define MB_DEFAULT_STREAM_THRESHOLD 16 /* 64K */65 66/*67 * for which requests use 2^N search using buddies68 */69#define MB_DEFAULT_ORDER2_REQS 270 71/*72 * default group prealloc size 512 blocks73 */74#define MB_DEFAULT_GROUP_PREALLOC 51275 76/*77 * Number of groups to search linearly before performing group scanning78 * optimization.79 */80#define MB_DEFAULT_LINEAR_LIMIT 481 82/*83 * Minimum number of groups that should be present in the file system to perform84 * group scanning optimizations.85 */86#define MB_DEFAULT_LINEAR_SCAN_THRESHOLD 1687 88/*89 * The maximum order upto which CR_BEST_AVAIL_LEN can trim a particular90 * allocation request. Example, if we have an order 7 request and max trim order91 * of 3, we can trim this request upto order 4.92 */93#define MB_DEFAULT_BEST_AVAIL_TRIM_ORDER 394 95/*96 * Number of valid buddy orders97 */98#define MB_NUM_ORDERS(sb) ((sb)->s_blocksize_bits + 2)99 100struct ext4_free_data {101 /* this links the free block information from sb_info */102 struct list_head efd_list;103 104 /* this links the free block information from group_info */105 struct rb_node efd_node;106 107 /* group which free block extent belongs */108 ext4_group_t efd_group;109 110 /* free block extent */111 ext4_grpblk_t efd_start_cluster;112 ext4_grpblk_t efd_count;113 114 /* transaction which freed this extent */115 tid_t efd_tid;116};117 118struct ext4_prealloc_space {119 union {120 struct rb_node inode_node; /* for inode PA rbtree */121 struct list_head lg_list; /* for lg PAs */122 } pa_node;123 struct list_head pa_group_list;124 union {125 struct list_head pa_tmp_list;126 struct rcu_head pa_rcu;127 } u;128 spinlock_t pa_lock;129 atomic_t pa_count;130 unsigned pa_deleted;131 ext4_fsblk_t pa_pstart; /* phys. block */132 ext4_lblk_t pa_lstart; /* log. block */133 ext4_grpblk_t pa_len; /* len of preallocated chunk */134 ext4_grpblk_t pa_free; /* how many blocks are free */135 unsigned short pa_type; /* pa type. inode or group */136 union {137 rwlock_t *inode_lock; /* locks the rbtree holding this PA */138 spinlock_t *lg_lock; /* locks the lg list holding this PA */139 } pa_node_lock;140 struct inode *pa_inode; /* used to get the inode during group discard */141};142 143enum {144 MB_INODE_PA = 0,145 MB_GROUP_PA = 1146};147 148struct ext4_free_extent {149 ext4_lblk_t fe_logical;150 ext4_grpblk_t fe_start; /* In cluster units */151 ext4_group_t fe_group;152 ext4_grpblk_t fe_len; /* In cluster units */153};154 155/*156 * Locality group:157 * we try to group all related changes together158 * so that writeback can flush/allocate them together as well159 * Size of lg_prealloc_list hash is determined by MB_DEFAULT_GROUP_PREALLOC160 * (512). We store prealloc space into the hash based on the pa_free blocks161 * order value.ie, fls(pa_free)-1;162 */163#define PREALLOC_TB_SIZE 10164struct ext4_locality_group {165 /* for allocator */166 /* to serialize allocates */167 struct mutex lg_mutex;168 /* list of preallocations */169 struct list_head lg_prealloc_list[PREALLOC_TB_SIZE];170 spinlock_t lg_prealloc_lock;171};172 173struct ext4_allocation_context {174 struct inode *ac_inode;175 struct super_block *ac_sb;176 177 /* original request */178 struct ext4_free_extent ac_o_ex;179 180 /* goal request (normalized ac_o_ex) */181 struct ext4_free_extent ac_g_ex;182 183 /* the best found extent */184 struct ext4_free_extent ac_b_ex;185 186 /* copy of the best found extent taken before preallocation efforts */187 struct ext4_free_extent ac_f_ex;188 189 /*190 * goal len can change in CR_BEST_AVAIL_LEN, so save the original len.191 * This is used while adjusting the PA window and for accounting.192 */193 ext4_grpblk_t ac_orig_goal_len;194 195 __u32 ac_flags; /* allocation hints */196 __u32 ac_groups_linear_remaining;197 __u16 ac_groups_scanned;198 __u16 ac_found;199 __u16 ac_cX_found[EXT4_MB_NUM_CRS];200 __u16 ac_tail;201 __u16 ac_buddy;202 __u8 ac_status;203 __u8 ac_criteria;204 __u8 ac_2order; /* if request is to allocate 2^N blocks and205 * N > 0, the field stores N, otherwise 0 */206 __u8 ac_op; /* operation, for history only */207 struct folio *ac_bitmap_folio;208 struct folio *ac_buddy_folio;209 struct ext4_prealloc_space *ac_pa;210 struct ext4_locality_group *ac_lg;211};212 213#define AC_STATUS_CONTINUE 1214#define AC_STATUS_FOUND 2215#define AC_STATUS_BREAK 3216 217struct ext4_buddy {218 struct folio *bd_buddy_folio;219 void *bd_buddy;220 struct folio *bd_bitmap_folio;221 void *bd_bitmap;222 struct ext4_group_info *bd_info;223 struct super_block *bd_sb;224 __u16 bd_blkbits;225 ext4_group_t bd_group;226};227 228static inline ext4_fsblk_t ext4_grp_offs_to_block(struct super_block *sb,229 struct ext4_free_extent *fex)230{231 return ext4_group_first_block_no(sb, fex->fe_group) +232 (fex->fe_start << EXT4_SB(sb)->s_cluster_bits);233}234 235static inline loff_t extent_logical_end(struct ext4_sb_info *sbi,236 struct ext4_free_extent *fex)237{238 /* Use loff_t to avoid end exceeding ext4_lblk_t max. */239 return (loff_t)fex->fe_logical + EXT4_C2B(sbi, fex->fe_len);240}241 242static inline loff_t pa_logical_end(struct ext4_sb_info *sbi,243 struct ext4_prealloc_space *pa)244{245 /* Use loff_t to avoid end exceeding ext4_lblk_t max. */246 return (loff_t)pa->pa_lstart + EXT4_C2B(sbi, pa->pa_len);247}248 249typedef int (*ext4_mballoc_query_range_fn)(250 struct super_block *sb,251 ext4_group_t agno,252 ext4_grpblk_t start,253 ext4_grpblk_t len,254 void *priv);255 256int257ext4_mballoc_query_range(258 struct super_block *sb,259 ext4_group_t agno,260 ext4_grpblk_t start,261 ext4_grpblk_t end,262 ext4_mballoc_query_range_fn formatter,263 void *priv);264 265#endif266