genirq: Prevent proc race against freeing of irq descriptors
[cascardo/linux.git] / kernel / irq / internals.h
1 /*
2  * IRQ subsystem internal functions and variables:
3  *
4  * Do not ever include this file from anything else than
5  * kernel/irq/. Do not even think about using any information outside
6  * of this file for your non core code.
7  */
8 #include <linux/irqdesc.h>
9 #include <linux/kernel_stat.h>
10
11 #ifdef CONFIG_SPARSE_IRQ
12 # define IRQ_BITMAP_BITS        (NR_IRQS + 8196)
13 #else
14 # define IRQ_BITMAP_BITS        NR_IRQS
15 #endif
16
17 #define istate core_internal_state__do_not_mess_with_it
18
19 extern bool noirqdebug;
20
21 /*
22  * Bits used by threaded handlers:
23  * IRQTF_RUNTHREAD - signals that the interrupt handler thread should run
24  * IRQTF_WARNED    - warning "IRQ_WAKE_THREAD w/o thread_fn" has been printed
25  * IRQTF_AFFINITY  - irq thread is requested to adjust affinity
26  * IRQTF_FORCED_THREAD  - irq action is force threaded
27  */
28 enum {
29         IRQTF_RUNTHREAD,
30         IRQTF_WARNED,
31         IRQTF_AFFINITY,
32         IRQTF_FORCED_THREAD,
33 };
34
35 /*
36  * Bit masks for desc->core_internal_state__do_not_mess_with_it
37  *
38  * IRQS_AUTODETECT              - autodetection in progress
39  * IRQS_SPURIOUS_DISABLED       - was disabled due to spurious interrupt
40  *                                detection
41  * IRQS_POLL_INPROGRESS         - polling in progress
42  * IRQS_ONESHOT                 - irq is not unmasked in primary handler
43  * IRQS_REPLAY                  - irq is replayed
44  * IRQS_WAITING                 - irq is waiting
45  * IRQS_PENDING                 - irq is pending and replayed later
46  * IRQS_SUSPENDED               - irq is suspended
47  */
48 enum {
49         IRQS_AUTODETECT         = 0x00000001,
50         IRQS_SPURIOUS_DISABLED  = 0x00000002,
51         IRQS_POLL_INPROGRESS    = 0x00000008,
52         IRQS_ONESHOT            = 0x00000020,
53         IRQS_REPLAY             = 0x00000040,
54         IRQS_WAITING            = 0x00000080,
55         IRQS_PENDING            = 0x00000200,
56         IRQS_SUSPENDED          = 0x00000800,
57 };
58
59 #include "debug.h"
60 #include "settings.h"
61
62 #define irq_data_to_desc(data)  container_of(data, struct irq_desc, irq_data)
63
64 extern int __irq_set_trigger(struct irq_desc *desc, unsigned int irq,
65                 unsigned long flags);
66 extern void __disable_irq(struct irq_desc *desc, unsigned int irq);
67 extern void __enable_irq(struct irq_desc *desc, unsigned int irq);
68
69 extern int irq_startup(struct irq_desc *desc, bool resend);
70 extern void irq_shutdown(struct irq_desc *desc);
71 extern void irq_enable(struct irq_desc *desc);
72 extern void irq_disable(struct irq_desc *desc);
73 extern void irq_percpu_enable(struct irq_desc *desc, unsigned int cpu);
74 extern void irq_percpu_disable(struct irq_desc *desc, unsigned int cpu);
75 extern void mask_irq(struct irq_desc *desc);
76 extern void unmask_irq(struct irq_desc *desc);
77 extern void unmask_threaded_irq(struct irq_desc *desc);
78
79 #ifdef CONFIG_SPARSE_IRQ
80 static inline void irq_mark_irq(unsigned int irq) { }
81 extern void irq_lock_sparse(void);
82 extern void irq_unlock_sparse(void);
83 #else
84 extern void irq_mark_irq(unsigned int irq);
85 static inline void irq_lock_sparse(void) { }
86 static inline void irq_unlock_sparse(void) { }
87 #endif
88
89 extern void init_kstat_irqs(struct irq_desc *desc, int node, int nr);
90
91 irqreturn_t handle_irq_event_percpu(struct irq_desc *desc, struct irqaction *action);
92 irqreturn_t handle_irq_event(struct irq_desc *desc);
93
94 /* Resending of interrupts :*/
95 void check_irq_resend(struct irq_desc *desc, unsigned int irq);
96 bool irq_wait_for_poll(struct irq_desc *desc);
97 void __irq_wake_thread(struct irq_desc *desc, struct irqaction *action);
98
99 #ifdef CONFIG_PROC_FS
100 extern void register_irq_proc(unsigned int irq, struct irq_desc *desc);
101 extern void unregister_irq_proc(unsigned int irq, struct irq_desc *desc);
102 extern void register_handler_proc(unsigned int irq, struct irqaction *action);
103 extern void unregister_handler_proc(unsigned int irq, struct irqaction *action);
104 #else
105 static inline void register_irq_proc(unsigned int irq, struct irq_desc *desc) { }
106 static inline void unregister_irq_proc(unsigned int irq, struct irq_desc *desc) { }
107 static inline void register_handler_proc(unsigned int irq,
108                                          struct irqaction *action) { }
109 static inline void unregister_handler_proc(unsigned int irq,
110                                            struct irqaction *action) { }
111 #endif
112
113 extern int irq_select_affinity_usr(unsigned int irq, struct cpumask *mask);
114
115 extern void irq_set_thread_affinity(struct irq_desc *desc);
116
117 extern int irq_do_set_affinity(struct irq_data *data,
118                                const struct cpumask *dest, bool force);
119
120 /* Inline functions for support of irq chips on slow busses */
121 static inline void chip_bus_lock(struct irq_desc *desc)
122 {
123         if (unlikely(desc->irq_data.chip->irq_bus_lock))
124                 desc->irq_data.chip->irq_bus_lock(&desc->irq_data);
125 }
126
127 static inline void chip_bus_sync_unlock(struct irq_desc *desc)
128 {
129         if (unlikely(desc->irq_data.chip->irq_bus_sync_unlock))
130                 desc->irq_data.chip->irq_bus_sync_unlock(&desc->irq_data);
131 }
132
133 #define _IRQ_DESC_CHECK         (1 << 0)
134 #define _IRQ_DESC_PERCPU        (1 << 1)
135
136 #define IRQ_GET_DESC_CHECK_GLOBAL       (_IRQ_DESC_CHECK)
137 #define IRQ_GET_DESC_CHECK_PERCPU       (_IRQ_DESC_CHECK | _IRQ_DESC_PERCPU)
138
139 struct irq_desc *
140 __irq_get_desc_lock(unsigned int irq, unsigned long *flags, bool bus,
141                     unsigned int check);
142 void __irq_put_desc_unlock(struct irq_desc *desc, unsigned long flags, bool bus);
143
144 static inline struct irq_desc *
145 irq_get_desc_buslock(unsigned int irq, unsigned long *flags, unsigned int check)
146 {
147         return __irq_get_desc_lock(irq, flags, true, check);
148 }
149
150 static inline void
151 irq_put_desc_busunlock(struct irq_desc *desc, unsigned long flags)
152 {
153         __irq_put_desc_unlock(desc, flags, true);
154 }
155
156 static inline struct irq_desc *
157 irq_get_desc_lock(unsigned int irq, unsigned long *flags, unsigned int check)
158 {
159         return __irq_get_desc_lock(irq, flags, false, check);
160 }
161
162 static inline void
163 irq_put_desc_unlock(struct irq_desc *desc, unsigned long flags)
164 {
165         __irq_put_desc_unlock(desc, flags, false);
166 }
167
168 /*
169  * Manipulation functions for irq_data.state
170  */
171 static inline void irqd_set_move_pending(struct irq_data *d)
172 {
173         d->state_use_accessors |= IRQD_SETAFFINITY_PENDING;
174 }
175
176 static inline void irqd_clr_move_pending(struct irq_data *d)
177 {
178         d->state_use_accessors &= ~IRQD_SETAFFINITY_PENDING;
179 }
180
181 static inline void irqd_clear(struct irq_data *d, unsigned int mask)
182 {
183         d->state_use_accessors &= ~mask;
184 }
185
186 static inline void irqd_set(struct irq_data *d, unsigned int mask)
187 {
188         d->state_use_accessors |= mask;
189 }
190
191 static inline bool irqd_has_set(struct irq_data *d, unsigned int mask)
192 {
193         return d->state_use_accessors & mask;
194 }
195
196 static inline void kstat_incr_irqs_this_cpu(unsigned int irq, struct irq_desc *desc)
197 {
198         __this_cpu_inc(*desc->kstat_irqs);
199         __this_cpu_inc(kstat.irqs_sum);
200 }
201
202 #ifdef CONFIG_PM_SLEEP
203 bool irq_pm_check_wakeup(struct irq_desc *desc);
204 void irq_pm_install_action(struct irq_desc *desc, struct irqaction *action);
205 void irq_pm_remove_action(struct irq_desc *desc, struct irqaction *action);
206 #else
207 static inline bool irq_pm_check_wakeup(struct irq_desc *desc) { return false; }
208 static inline void
209 irq_pm_install_action(struct irq_desc *desc, struct irqaction *action) { }
210 static inline void
211 irq_pm_remove_action(struct irq_desc *desc, struct irqaction *action) { }
212 #endif