Commit | Line | Data |
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8f6e39a7 MC |
1 | /* |
2 | * fs/ext4/mballoc.h | |
3 | * | |
4 | * Written by: Alex Tomas <alex@clusterfs.com> | |
5 | * | |
6 | */ | |
7 | #ifndef _EXT4_MBALLOC_H | |
8 | #define _EXT4_MBALLOC_H | |
9 | ||
10 | #include <linux/time.h> | |
11 | #include <linux/fs.h> | |
12 | #include <linux/namei.h> | |
13 | #include <linux/quotaops.h> | |
14 | #include <linux/buffer_head.h> | |
15 | #include <linux/module.h> | |
16 | #include <linux/swap.h> | |
17 | #include <linux/proc_fs.h> | |
18 | #include <linux/pagemap.h> | |
19 | #include <linux/seq_file.h> | |
8a0aba73 | 20 | #include <linux/blkdev.h> |
920313a7 | 21 | #include <linux/mutex.h> |
8f6e39a7 MC |
22 | #include "ext4_jbd2.h" |
23 | #include "ext4.h" | |
8f6e39a7 MC |
24 | |
25 | /* | |
26 | * with AGGRESSIVE_CHECK allocator runs consistency checks over | |
27 | * structures. these checks slow things down a lot | |
28 | */ | |
29 | #define AGGRESSIVE_CHECK__ | |
30 | ||
31 | /* | |
32 | * with DOUBLE_CHECK defined mballoc creates persistent in-core | |
33 | * bitmaps, maintains and uses them to check for double allocations | |
34 | */ | |
35 | #define DOUBLE_CHECK__ | |
36 | ||
37 | /* | |
38 | */ | |
6ba495e9 TT |
39 | #ifdef CONFIG_EXT4_DEBUG |
40 | extern u8 mb_enable_debug; | |
41 | ||
42 | #define mb_debug(n, fmt, a...) \ | |
43 | do { \ | |
44 | if ((n) <= mb_enable_debug) { \ | |
45 | printk(KERN_DEBUG "(%s, %d): %s: ", \ | |
46 | __FILE__, __LINE__, __func__); \ | |
47 | printk(fmt, ## a); \ | |
48 | } \ | |
49 | } while (0) | |
8f6e39a7 | 50 | #else |
6ba495e9 | 51 | #define mb_debug(n, fmt, a...) |
8f6e39a7 MC |
52 | #endif |
53 | ||
8f6e39a7 MC |
54 | #define EXT4_MB_HISTORY_ALLOC 1 /* allocation */ |
55 | #define EXT4_MB_HISTORY_PREALLOC 2 /* preallocated blocks used */ | |
8f6e39a7 MC |
56 | |
57 | /* | |
58 | * How long mballoc can look for a best extent (in found extents) | |
59 | */ | |
60 | #define MB_DEFAULT_MAX_TO_SCAN 200 | |
61 | ||
62 | /* | |
63 | * How long mballoc must look for a best extent | |
64 | */ | |
65 | #define MB_DEFAULT_MIN_TO_SCAN 10 | |
66 | ||
67 | /* | |
68 | * How many groups mballoc will scan looking for the best chunk | |
69 | */ | |
70 | #define MB_DEFAULT_MAX_GROUPS_TO_SCAN 5 | |
71 | ||
72 | /* | |
73 | * with 'ext4_mb_stats' allocator will collect stats that will be | |
74 | * shown at umount. The collecting costs though! | |
75 | */ | |
90576c0b | 76 | #define MB_DEFAULT_STATS 0 |
8f6e39a7 MC |
77 | |
78 | /* | |
79 | * files smaller than MB_DEFAULT_STREAM_THRESHOLD are served | |
80 | * by the stream allocator, which purpose is to pack requests | |
81 | * as close each to other as possible to produce smooth I/O traffic | |
82 | * We use locality group prealloc space for stream request. | |
83 | * We can tune the same via /proc/fs/ext4/<parition>/stream_req | |
84 | */ | |
85 | #define MB_DEFAULT_STREAM_THRESHOLD 16 /* 64K */ | |
86 | ||
87 | /* | |
88 | * for which requests use 2^N search using buddies | |
89 | */ | |
90 | #define MB_DEFAULT_ORDER2_REQS 2 | |
91 | ||
92 | /* | |
93 | * default group prealloc size 512 blocks | |
94 | */ | |
95 | #define MB_DEFAULT_GROUP_PREALLOC 512 | |
96 | ||
8f6e39a7 | 97 | |
c894058d | 98 | struct ext4_free_data { |
18aadd47 BJ |
99 | /* MUST be the first member */ |
100 | struct ext4_journal_cb_entry efd_jce; | |
101 | ||
102 | /* ext4_free_data private data starts from here */ | |
8f6e39a7 | 103 | |
18aadd47 BJ |
104 | /* this links the free block information from group_info */ |
105 | struct rb_node efd_node; | |
c894058d AK |
106 | |
107 | /* group which free block extent belongs */ | |
18aadd47 | 108 | ext4_group_t efd_group; |
c894058d AK |
109 | |
110 | /* free block extent */ | |
18aadd47 BJ |
111 | ext4_grpblk_t efd_start_cluster; |
112 | ext4_grpblk_t efd_count; | |
c894058d AK |
113 | |
114 | /* transaction which freed this extent */ | |
18aadd47 | 115 | tid_t efd_tid; |
8f6e39a7 MC |
116 | }; |
117 | ||
8f6e39a7 MC |
118 | struct ext4_prealloc_space { |
119 | struct list_head pa_inode_list; | |
120 | struct list_head pa_group_list; | |
121 | union { | |
122 | struct list_head pa_tmp_list; | |
123 | struct rcu_head pa_rcu; | |
124 | } u; | |
125 | spinlock_t pa_lock; | |
126 | atomic_t pa_count; | |
127 | unsigned pa_deleted; | |
128 | ext4_fsblk_t pa_pstart; /* phys. block */ | |
129 | ext4_lblk_t pa_lstart; /* log. block */ | |
a36b4498 ES |
130 | ext4_grpblk_t pa_len; /* len of preallocated chunk */ |
131 | ext4_grpblk_t pa_free; /* how many blocks are free */ | |
cc0fb9ad | 132 | unsigned short pa_type; /* pa type. inode or group */ |
8f6e39a7 MC |
133 | spinlock_t *pa_obj_lock; |
134 | struct inode *pa_inode; /* hack, for history only */ | |
135 | }; | |
136 | ||
cc0fb9ad AK |
137 | enum { |
138 | MB_INODE_PA = 0, | |
139 | MB_GROUP_PA = 1 | |
140 | }; | |
8f6e39a7 MC |
141 | |
142 | struct ext4_free_extent { | |
143 | ext4_lblk_t fe_logical; | |
53accfa9 | 144 | ext4_grpblk_t fe_start; /* In cluster units */ |
8f6e39a7 | 145 | ext4_group_t fe_group; |
53accfa9 | 146 | ext4_grpblk_t fe_len; /* In cluster units */ |
8f6e39a7 MC |
147 | }; |
148 | ||
149 | /* | |
150 | * Locality group: | |
151 | * we try to group all related changes together | |
152 | * so that writeback can flush/allocate them together as well | |
6be2ded1 AK |
153 | * Size of lg_prealloc_list hash is determined by MB_DEFAULT_GROUP_PREALLOC |
154 | * (512). We store prealloc space into the hash based on the pa_free blocks | |
155 | * order value.ie, fls(pa_free)-1; | |
8f6e39a7 | 156 | */ |
6be2ded1 | 157 | #define PREALLOC_TB_SIZE 10 |
8f6e39a7 MC |
158 | struct ext4_locality_group { |
159 | /* for allocator */ | |
6be2ded1 AK |
160 | /* to serialize allocates */ |
161 | struct mutex lg_mutex; | |
162 | /* list of preallocations */ | |
163 | struct list_head lg_prealloc_list[PREALLOC_TB_SIZE]; | |
8f6e39a7 MC |
164 | spinlock_t lg_prealloc_lock; |
165 | }; | |
166 | ||
167 | struct ext4_allocation_context { | |
168 | struct inode *ac_inode; | |
169 | struct super_block *ac_sb; | |
170 | ||
171 | /* original request */ | |
172 | struct ext4_free_extent ac_o_ex; | |
173 | ||
58696f3a | 174 | /* goal request (normalized ac_o_ex) */ |
8f6e39a7 MC |
175 | struct ext4_free_extent ac_g_ex; |
176 | ||
177 | /* the best found extent */ | |
178 | struct ext4_free_extent ac_b_ex; | |
179 | ||
ff3fc173 | 180 | /* copy of the best found extent taken before preallocation efforts */ |
8f6e39a7 MC |
181 | struct ext4_free_extent ac_f_ex; |
182 | ||
183 | /* number of iterations done. we have to track to limit searching */ | |
184 | unsigned long ac_ex_scanned; | |
185 | __u16 ac_groups_scanned; | |
186 | __u16 ac_found; | |
187 | __u16 ac_tail; | |
188 | __u16 ac_buddy; | |
189 | __u16 ac_flags; /* allocation hints */ | |
190 | __u8 ac_status; | |
191 | __u8 ac_criteria; | |
8f6e39a7 MC |
192 | __u8 ac_2order; /* if request is to allocate 2^N blocks and |
193 | * N > 0, the field stores N, otherwise 0 */ | |
194 | __u8 ac_op; /* operation, for history only */ | |
195 | struct page *ac_bitmap_page; | |
196 | struct page *ac_buddy_page; | |
197 | struct ext4_prealloc_space *ac_pa; | |
198 | struct ext4_locality_group *ac_lg; | |
199 | }; | |
200 | ||
201 | #define AC_STATUS_CONTINUE 1 | |
202 | #define AC_STATUS_FOUND 2 | |
203 | #define AC_STATUS_BREAK 3 | |
204 | ||
8f6e39a7 MC |
205 | struct ext4_buddy { |
206 | struct page *bd_buddy_page; | |
207 | void *bd_buddy; | |
208 | struct page *bd_bitmap_page; | |
209 | void *bd_bitmap; | |
210 | struct ext4_group_info *bd_info; | |
211 | struct super_block *bd_sb; | |
212 | __u16 bd_blkbits; | |
213 | ext4_group_t bd_group; | |
214 | }; | |
8f6e39a7 | 215 | |
c3a326a6 | 216 | static inline ext4_fsblk_t ext4_grp_offs_to_block(struct super_block *sb, |
8f6e39a7 MC |
217 | struct ext4_free_extent *fex) |
218 | { | |
3212a80a TT |
219 | return ext4_group_first_block_no(sb, fex->fe_group) + |
220 | (fex->fe_start << EXT4_SB(sb)->s_cluster_bits); | |
8f6e39a7 MC |
221 | } |
222 | #endif |