diff options
author | Al Viro <viro@zeniv.linux.org.uk> | 2015-01-10 17:53:21 -0500 |
---|---|---|
committer | Al Viro <viro@zeniv.linux.org.uk> | 2015-01-25 23:17:28 -0500 |
commit | 59eda0e07f43c950d31756213b607af673e551f0 (patch) | |
tree | f40f7b67133576c36a65a4cba9aca5df68d00f34 /fs/fs_pin.c | |
parent | fdab684d7202774bfd8762d4a656a553b787c8ec (diff) |
new fs_pin killing logics
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Diffstat (limited to 'fs/fs_pin.c')
-rw-r--r-- | fs/fs_pin.c | 54 |
1 files changed, 48 insertions, 6 deletions
diff --git a/fs/fs_pin.c b/fs/fs_pin.c index 50ef7d2ef03c..0c77bdc238b2 100644 --- a/fs/fs_pin.c +++ b/fs/fs_pin.c | |||
@@ -1,4 +1,5 @@ | |||
1 | #include <linux/fs.h> | 1 | #include <linux/fs.h> |
2 | #include <linux/sched.h> | ||
2 | #include <linux/slab.h> | 3 | #include <linux/slab.h> |
3 | #include <linux/fs_pin.h> | 4 | #include <linux/fs_pin.h> |
4 | #include "internal.h" | 5 | #include "internal.h" |
@@ -12,6 +13,10 @@ void pin_remove(struct fs_pin *pin) | |||
12 | hlist_del(&pin->m_list); | 13 | hlist_del(&pin->m_list); |
13 | hlist_del(&pin->s_list); | 14 | hlist_del(&pin->s_list); |
14 | spin_unlock(&pin_lock); | 15 | spin_unlock(&pin_lock); |
16 | spin_lock_irq(&pin->wait.lock); | ||
17 | pin->done = 1; | ||
18 | wake_up_locked(&pin->wait); | ||
19 | spin_unlock_irq(&pin->wait.lock); | ||
15 | } | 20 | } |
16 | 21 | ||
17 | void pin_insert_group(struct fs_pin *pin, struct vfsmount *m, struct hlist_head *p) | 22 | void pin_insert_group(struct fs_pin *pin, struct vfsmount *m, struct hlist_head *p) |
@@ -28,19 +33,58 @@ void pin_insert(struct fs_pin *pin, struct vfsmount *m) | |||
28 | pin_insert_group(pin, m, &m->mnt_sb->s_pins); | 33 | pin_insert_group(pin, m, &m->mnt_sb->s_pins); |
29 | } | 34 | } |
30 | 35 | ||
36 | void pin_kill(struct fs_pin *p) | ||
37 | { | ||
38 | wait_queue_t wait; | ||
39 | |||
40 | if (!p) { | ||
41 | rcu_read_unlock(); | ||
42 | return; | ||
43 | } | ||
44 | init_wait(&wait); | ||
45 | spin_lock_irq(&p->wait.lock); | ||
46 | if (likely(!p->done)) { | ||
47 | p->done = -1; | ||
48 | spin_unlock_irq(&p->wait.lock); | ||
49 | rcu_read_unlock(); | ||
50 | p->kill(p); | ||
51 | return; | ||
52 | } | ||
53 | if (p->done > 0) { | ||
54 | spin_unlock_irq(&p->wait.lock); | ||
55 | rcu_read_unlock(); | ||
56 | return; | ||
57 | } | ||
58 | __add_wait_queue(&p->wait, &wait); | ||
59 | while (1) { | ||
60 | set_current_state(TASK_UNINTERRUPTIBLE); | ||
61 | spin_unlock_irq(&p->wait.lock); | ||
62 | rcu_read_unlock(); | ||
63 | schedule(); | ||
64 | rcu_read_lock(); | ||
65 | if (likely(list_empty(&wait.task_list))) | ||
66 | break; | ||
67 | /* OK, we know p couldn't have been freed yet */ | ||
68 | spin_lock_irq(&p->wait.lock); | ||
69 | if (p->done > 0) { | ||
70 | spin_unlock_irq(&p->wait.lock); | ||
71 | break; | ||
72 | } | ||
73 | } | ||
74 | rcu_read_unlock(); | ||
75 | } | ||
76 | |||
31 | void mnt_pin_kill(struct mount *m) | 77 | void mnt_pin_kill(struct mount *m) |
32 | { | 78 | { |
33 | while (1) { | 79 | while (1) { |
34 | struct hlist_node *p; | 80 | struct hlist_node *p; |
35 | struct fs_pin *pin; | ||
36 | rcu_read_lock(); | 81 | rcu_read_lock(); |
37 | p = ACCESS_ONCE(m->mnt_pins.first); | 82 | p = ACCESS_ONCE(m->mnt_pins.first); |
38 | if (!p) { | 83 | if (!p) { |
39 | rcu_read_unlock(); | 84 | rcu_read_unlock(); |
40 | break; | 85 | break; |
41 | } | 86 | } |
42 | pin = hlist_entry(p, struct fs_pin, m_list); | 87 | pin_kill(hlist_entry(p, struct fs_pin, m_list)); |
43 | pin->kill(pin); | ||
44 | } | 88 | } |
45 | } | 89 | } |
46 | 90 | ||
@@ -48,14 +92,12 @@ void group_pin_kill(struct hlist_head *p) | |||
48 | { | 92 | { |
49 | while (1) { | 93 | while (1) { |
50 | struct hlist_node *q; | 94 | struct hlist_node *q; |
51 | struct fs_pin *pin; | ||
52 | rcu_read_lock(); | 95 | rcu_read_lock(); |
53 | q = ACCESS_ONCE(p->first); | 96 | q = ACCESS_ONCE(p->first); |
54 | if (!q) { | 97 | if (!q) { |
55 | rcu_read_unlock(); | 98 | rcu_read_unlock(); |
56 | break; | 99 | break; |
57 | } | 100 | } |
58 | pin = hlist_entry(q, struct fs_pin, s_list); | 101 | pin_kill(hlist_entry(q, struct fs_pin, s_list)); |
59 | pin->kill(pin); | ||
60 | } | 102 | } |
61 | } | 103 | } |