Branch data Line data Source code
1 : : /*
2 : : * include/linux/backing-dev.h
3 : : *
4 : : * low-level device information and state which is propagated up through
5 : : * to high-level code.
6 : : */
7 : :
8 : : #ifndef _LINUX_BACKING_DEV_H
9 : : #define _LINUX_BACKING_DEV_H
10 : :
11 : : #include <linux/percpu_counter.h>
12 : : #include <linux/log2.h>
13 : : #include <linux/flex_proportions.h>
14 : : #include <linux/kernel.h>
15 : : #include <linux/fs.h>
16 : : #include <linux/sched.h>
17 : : #include <linux/timer.h>
18 : : #include <linux/writeback.h>
19 : : #include <linux/atomic.h>
20 : : #include <linux/sysctl.h>
21 : : #include <linux/workqueue.h>
22 : :
23 : : struct page;
24 : : struct device;
25 : : struct dentry;
26 : :
27 : : /*
28 : : * Bits in backing_dev_info.state
29 : : */
30 : : enum bdi_state {
31 : : BDI_wb_alloc, /* Default embedded wb allocated */
32 : : BDI_async_congested, /* The async (write) queue is getting full */
33 : : BDI_sync_congested, /* The sync queue is getting full */
34 : : BDI_registered, /* bdi_register() was done */
35 : : BDI_writeback_running, /* Writeback is in progress */
36 : : BDI_unused, /* Available bits start here */
37 : : };
38 : :
39 : : typedef int (congested_fn)(void *, int);
40 : :
41 : : enum bdi_stat_item {
42 : : BDI_RECLAIMABLE,
43 : : BDI_WRITEBACK,
44 : : BDI_DIRTIED,
45 : : BDI_WRITTEN,
46 : : NR_BDI_STAT_ITEMS
47 : : };
48 : :
49 : : #define BDI_STAT_BATCH (8*(1+ilog2(nr_cpu_ids)))
50 : :
51 : : struct bdi_writeback {
52 : : struct backing_dev_info *bdi; /* our parent bdi */
53 : : unsigned int nr;
54 : :
55 : : unsigned long last_old_flush; /* last old data flush */
56 : :
57 : : struct delayed_work dwork; /* work item used for writeback */
58 : : struct list_head b_dirty; /* dirty inodes */
59 : : struct list_head b_io; /* parked for writeback */
60 : : struct list_head b_more_io; /* parked for more writeback */
61 : : spinlock_t list_lock; /* protects the b_* lists */
62 : : };
63 : :
64 : : struct backing_dev_info {
65 : : struct list_head bdi_list;
66 : : unsigned long ra_pages; /* max readahead in PAGE_CACHE_SIZE units */
67 : : unsigned long state; /* Always use atomic bitops on this */
68 : : unsigned int capabilities; /* Device capabilities */
69 : : congested_fn *congested_fn; /* Function pointer if device is md/dm */
70 : : void *congested_data; /* Pointer to aux data for congested func */
71 : :
72 : : char *name;
73 : :
74 : : struct percpu_counter bdi_stat[NR_BDI_STAT_ITEMS];
75 : :
76 : : unsigned long bw_time_stamp; /* last time write bw is updated */
77 : : unsigned long dirtied_stamp;
78 : : unsigned long written_stamp; /* pages written at bw_time_stamp */
79 : : unsigned long write_bandwidth; /* the estimated write bandwidth */
80 : : unsigned long avg_write_bandwidth; /* further smoothed write bw */
81 : :
82 : : /*
83 : : * The base dirty throttle rate, re-calculated on every 200ms.
84 : : * All the bdi tasks' dirty rate will be curbed under it.
85 : : * @dirty_ratelimit tracks the estimated @balanced_dirty_ratelimit
86 : : * in small steps and is much more smooth/stable than the latter.
87 : : */
88 : : unsigned long dirty_ratelimit;
89 : : unsigned long balanced_dirty_ratelimit;
90 : :
91 : : struct fprop_local_percpu completions;
92 : : int dirty_exceeded;
93 : :
94 : : unsigned int min_ratio;
95 : : unsigned int max_ratio, max_prop_frac;
96 : :
97 : : struct bdi_writeback wb; /* default writeback info for this bdi */
98 : : spinlock_t wb_lock; /* protects work_list */
99 : :
100 : : struct list_head work_list;
101 : :
102 : : struct device *dev;
103 : :
104 : : struct timer_list laptop_mode_wb_timer;
105 : :
106 : : #ifdef CONFIG_DEBUG_FS
107 : : struct dentry *debug_dir;
108 : : struct dentry *debug_stats;
109 : : #endif
110 : : };
111 : :
112 : : int __must_check bdi_init(struct backing_dev_info *bdi);
113 : : void bdi_destroy(struct backing_dev_info *bdi);
114 : :
115 : : __printf(3, 4)
116 : : int bdi_register(struct backing_dev_info *bdi, struct device *parent,
117 : : const char *fmt, ...);
118 : : int bdi_register_dev(struct backing_dev_info *bdi, dev_t dev);
119 : : void bdi_unregister(struct backing_dev_info *bdi);
120 : : int __must_check bdi_setup_and_register(struct backing_dev_info *, char *, unsigned int);
121 : : void bdi_start_writeback(struct backing_dev_info *bdi, long nr_pages,
122 : : enum wb_reason reason);
123 : : void bdi_start_background_writeback(struct backing_dev_info *bdi);
124 : : void bdi_writeback_workfn(struct work_struct *work);
125 : : int bdi_has_dirty_io(struct backing_dev_info *bdi);
126 : : void bdi_wakeup_thread_delayed(struct backing_dev_info *bdi);
127 : : void bdi_lock_two(struct bdi_writeback *wb1, struct bdi_writeback *wb2);
128 : :
129 : : extern spinlock_t bdi_lock;
130 : : extern struct list_head bdi_list;
131 : :
132 : : extern struct workqueue_struct *bdi_wq;
133 : :
134 : : static inline int wb_has_dirty_io(struct bdi_writeback *wb)
135 : : {
136 [ + + ][ + + ]: 64142 : return !list_empty(&wb->b_dirty) ||
137 [ + + ][ + + ]: 7367023 : !list_empty(&wb->b_io) ||
[ + + ][ + + ]
138 : 63055 : !list_empty(&wb->b_more_io);
139 : : }
140 : :
141 : : static inline void __add_bdi_stat(struct backing_dev_info *bdi,
142 : : enum bdi_stat_item item, s64 amount)
143 : : {
144 [ - + ][ # # ]: 23912784 : __percpu_counter_add(&bdi->bdi_stat[item], amount, BDI_STAT_BATCH);
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ - + ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ - + ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ - + ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ - + ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ - + ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ - + ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ - + ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
145 : : }
146 : :
147 : : static inline void __inc_bdi_stat(struct backing_dev_info *bdi,
148 : : enum bdi_stat_item item)
149 : : {
150 : : __add_bdi_stat(bdi, item, 1);
151 : : }
152 : :
153 : : static inline void inc_bdi_stat(struct backing_dev_info *bdi,
154 : : enum bdi_stat_item item)
155 : : {
156 : : unsigned long flags;
157 : :
158 : : local_irq_save(flags);
159 : : __inc_bdi_stat(bdi, item);
160 [ # # ]: 0 : local_irq_restore(flags);
161 : : }
162 : :
163 : : static inline void __dec_bdi_stat(struct backing_dev_info *bdi,
164 : : enum bdi_stat_item item)
165 : : {
166 : : __add_bdi_stat(bdi, item, -1);
167 : : }
168 : :
169 : : static inline void dec_bdi_stat(struct backing_dev_info *bdi,
170 : : enum bdi_stat_item item)
171 : : {
172 : : unsigned long flags;
173 : :
174 : : local_irq_save(flags);
175 : : __dec_bdi_stat(bdi, item);
176 [ - + - + ]: 2223231 : local_irq_restore(flags);
177 : : }
178 : :
179 : : static inline s64 bdi_stat(struct backing_dev_info *bdi,
180 : : enum bdi_stat_item item)
181 : : {
182 : 13524 : return percpu_counter_read_positive(&bdi->bdi_stat[item]);
183 : : }
184 : :
185 : : static inline s64 __bdi_stat_sum(struct backing_dev_info *bdi,
186 : : enum bdi_stat_item item)
187 : : {
188 : 0 : return percpu_counter_sum_positive(&bdi->bdi_stat[item]);
189 : : }
190 : :
191 : : static inline s64 bdi_stat_sum(struct backing_dev_info *bdi,
192 : : enum bdi_stat_item item)
193 : : {
194 : : s64 sum;
195 : : unsigned long flags;
196 : :
197 : : local_irq_save(flags);
198 : : sum = __bdi_stat_sum(bdi, item);
199 [ # # # # : 0 : local_irq_restore(flags);
# # # # ]
200 : :
201 : : return sum;
202 : : }
203 : :
204 : : extern void bdi_writeout_inc(struct backing_dev_info *bdi);
205 : :
206 : : /*
207 : : * maximal error of a stat counter.
208 : : */
209 : : static inline unsigned long bdi_stat_error(struct backing_dev_info *bdi)
210 : : {
211 : : #ifdef CONFIG_SMP
212 [ # # ][ # # ]: 9066 : return nr_cpu_ids * BDI_STAT_BATCH;
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ - + ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
213 : : #else
214 : : return 1;
215 : : #endif
216 : : }
217 : :
218 : : int bdi_set_min_ratio(struct backing_dev_info *bdi, unsigned int min_ratio);
219 : : int bdi_set_max_ratio(struct backing_dev_info *bdi, unsigned int max_ratio);
220 : :
221 : : /*
222 : : * Flags in backing_dev_info::capability
223 : : *
224 : : * The first three flags control whether dirty pages will contribute to the
225 : : * VM's accounting and whether writepages() should be called for dirty pages
226 : : * (something that would not, for example, be appropriate for ramfs)
227 : : *
228 : : * WARNING: these flags are closely related and should not normally be
229 : : * used separately. The BDI_CAP_NO_ACCT_AND_WRITEBACK combines these
230 : : * three flags into a single convenience macro.
231 : : *
232 : : * BDI_CAP_NO_ACCT_DIRTY: Dirty pages shouldn't contribute to accounting
233 : : * BDI_CAP_NO_WRITEBACK: Don't write pages back
234 : : * BDI_CAP_NO_ACCT_WB: Don't automatically account writeback pages
235 : : *
236 : : * These flags let !MMU mmap() govern direct device mapping vs immediate
237 : : * copying more easily for MAP_PRIVATE, especially for ROM filesystems.
238 : : *
239 : : * BDI_CAP_MAP_COPY: Copy can be mapped (MAP_PRIVATE)
240 : : * BDI_CAP_MAP_DIRECT: Can be mapped directly (MAP_SHARED)
241 : : * BDI_CAP_READ_MAP: Can be mapped for reading
242 : : * BDI_CAP_WRITE_MAP: Can be mapped for writing
243 : : * BDI_CAP_EXEC_MAP: Can be mapped for execution
244 : : *
245 : : * BDI_CAP_SWAP_BACKED: Count shmem/tmpfs objects as swap-backed.
246 : : *
247 : : * BDI_CAP_STRICTLIMIT: Keep number of dirty pages below bdi threshold.
248 : : */
249 : : #define BDI_CAP_NO_ACCT_DIRTY 0x00000001
250 : : #define BDI_CAP_NO_WRITEBACK 0x00000002
251 : : #define BDI_CAP_MAP_COPY 0x00000004
252 : : #define BDI_CAP_MAP_DIRECT 0x00000008
253 : : #define BDI_CAP_READ_MAP 0x00000010
254 : : #define BDI_CAP_WRITE_MAP 0x00000020
255 : : #define BDI_CAP_EXEC_MAP 0x00000040
256 : : #define BDI_CAP_NO_ACCT_WB 0x00000080
257 : : #define BDI_CAP_SWAP_BACKED 0x00000100
258 : : #define BDI_CAP_STABLE_WRITES 0x00000200
259 : : #define BDI_CAP_STRICTLIMIT 0x00000400
260 : :
261 : : #define BDI_CAP_VMFLAGS \
262 : : (BDI_CAP_READ_MAP | BDI_CAP_WRITE_MAP | BDI_CAP_EXEC_MAP)
263 : :
264 : : #define BDI_CAP_NO_ACCT_AND_WRITEBACK \
265 : : (BDI_CAP_NO_WRITEBACK | BDI_CAP_NO_ACCT_DIRTY | BDI_CAP_NO_ACCT_WB)
266 : :
267 : : #if defined(VM_MAYREAD) && \
268 : : (BDI_CAP_READ_MAP != VM_MAYREAD || \
269 : : BDI_CAP_WRITE_MAP != VM_MAYWRITE || \
270 : : BDI_CAP_EXEC_MAP != VM_MAYEXEC)
271 : : #error please change backing_dev_info::capabilities flags
272 : : #endif
273 : :
274 : : extern struct backing_dev_info default_backing_dev_info;
275 : : extern struct backing_dev_info noop_backing_dev_info;
276 : :
277 : : int writeback_in_progress(struct backing_dev_info *bdi);
278 : :
279 : : static inline int bdi_congested(struct backing_dev_info *bdi, int bdi_bits)
280 : : {
281 [ - + ][ - + ]: 133968 : if (bdi->congested_fn)
[ - + ]
282 : 0 : return bdi->congested_fn(bdi->congested_data, bdi_bits);
283 : 113987 : return (bdi->state & bdi_bits);
284 : : }
285 : :
286 : : static inline int bdi_read_congested(struct backing_dev_info *bdi)
287 : : {
288 : : return bdi_congested(bdi, 1 << BDI_sync_congested);
289 : : }
290 : :
291 : : static inline int bdi_write_congested(struct backing_dev_info *bdi)
292 : : {
293 : : return bdi_congested(bdi, 1 << BDI_async_congested);
294 : : }
295 : :
296 : : static inline int bdi_rw_congested(struct backing_dev_info *bdi)
297 : : {
298 : : return bdi_congested(bdi, (1 << BDI_sync_congested) |
299 : : (1 << BDI_async_congested));
300 : : }
301 : :
302 : : enum {
303 : : BLK_RW_ASYNC = 0,
304 : : BLK_RW_SYNC = 1,
305 : : };
306 : :
307 : : void clear_bdi_congested(struct backing_dev_info *bdi, int sync);
308 : : void set_bdi_congested(struct backing_dev_info *bdi, int sync);
309 : : long congestion_wait(int sync, long timeout);
310 : : long wait_iff_congested(struct zone *zone, int sync, long timeout);
311 : : int pdflush_proc_obsolete(struct ctl_table *table, int write,
312 : : void __user *buffer, size_t *lenp, loff_t *ppos);
313 : :
314 : : static inline bool bdi_cap_stable_pages_required(struct backing_dev_info *bdi)
315 : : {
316 : 14103373 : return bdi->capabilities & BDI_CAP_STABLE_WRITES;
317 : : }
318 : :
319 : : static inline bool bdi_cap_writeback_dirty(struct backing_dev_info *bdi)
320 : : {
321 : 201098 : return !(bdi->capabilities & BDI_CAP_NO_WRITEBACK);
322 : : }
323 : :
324 : : static inline bool bdi_cap_account_dirty(struct backing_dev_info *bdi)
325 : : {
326 : 18523772 : return !(bdi->capabilities & BDI_CAP_NO_ACCT_DIRTY);
327 : : }
328 : :
329 : : static inline bool bdi_cap_account_writeback(struct backing_dev_info *bdi)
330 : : {
331 : : /* Paranoia: BDI_CAP_NO_WRITEBACK implies BDI_CAP_NO_ACCT_WB */
332 : 1977293 : return !(bdi->capabilities & (BDI_CAP_NO_ACCT_WB |
333 : : BDI_CAP_NO_WRITEBACK));
334 : : }
335 : :
336 : : static inline bool bdi_cap_swap_backed(struct backing_dev_info *bdi)
337 : : {
338 : 1 : return bdi->capabilities & BDI_CAP_SWAP_BACKED;
339 : : }
340 : :
341 : : static inline bool mapping_cap_writeback_dirty(struct address_space *mapping)
342 : : {
343 : 81484 : return bdi_cap_writeback_dirty(mapping->backing_dev_info);
344 : : }
345 : :
346 : : static inline bool mapping_cap_account_dirty(struct address_space *mapping)
347 : : {
348 : 11336377 : return bdi_cap_account_dirty(mapping->backing_dev_info);
349 : : }
350 : :
351 : : static inline bool mapping_cap_swap_backed(struct address_space *mapping)
352 : : {
353 : 1 : return bdi_cap_swap_backed(mapping->backing_dev_info);
354 : : }
355 : :
356 : : static inline int bdi_sched_wait(void *word)
357 : : {
358 : : schedule();
359 : : return 0;
360 : : }
361 : :
362 : : #endif /* _LINUX_BACKING_DEV_H */
|
