git.sesse.net Git - bcachefs-tools-debian/blob - libbcachefs/sb-members.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 #ifndef _BCACHEFS_SB_MEMBERS_H
   3 #define _BCACHEFS_SB_MEMBERS_H
   4
   5 int bch2_members_v2_init(struct bch_fs *c);
   6 int bch_members_cpy_v2_v1(struct bch_sb_handle *disk_sb);
   7 struct bch_member *bch2_members_v2_get_mut(struct bch_sb *sb, int i);
   8 struct bch_member bch2_sb_member_get(struct bch_sb *sb, int i);
   9
  10 static inline bool bch2_dev_is_online(struct bch_dev *ca)
  11 {
  12         return !percpu_ref_is_zero(&ca->io_ref);
  13 }
  14
  15 static inline bool bch2_dev_is_readable(struct bch_dev *ca)
  16 {
  17         return bch2_dev_is_online(ca) &&
  18                 ca->mi.state != BCH_MEMBER_STATE_failed;
  19 }
  20
  21 static inline bool bch2_dev_get_ioref(struct bch_dev *ca, int rw)
  22 {
  23         if (!percpu_ref_tryget(&ca->io_ref))
  24                 return false;
  25
  26         if (ca->mi.state == BCH_MEMBER_STATE_rw ||
  27             (ca->mi.state == BCH_MEMBER_STATE_ro && rw == READ))
  28                 return true;
  29
  30         percpu_ref_put(&ca->io_ref);
  31         return false;
  32 }
  33
  34 static inline unsigned dev_mask_nr(const struct bch_devs_mask *devs)
  35 {
  36         return bitmap_weight(devs->d, BCH_SB_MEMBERS_MAX);
  37 }
  38
  39 static inline bool bch2_dev_list_has_dev(struct bch_devs_list devs,
  40                                          unsigned dev)
  41 {
  42         unsigned i;
  43
  44         for (i = 0; i < devs.nr; i++)
  45                 if (devs.devs[i] == dev)
  46                         return true;
  47
  48         return false;
  49 }
  50
  51 static inline void bch2_dev_list_drop_dev(struct bch_devs_list *devs,
  52                                           unsigned dev)
  53 {
  54         unsigned i;
  55
  56         for (i = 0; i < devs->nr; i++)
  57                 if (devs->devs[i] == dev) {
  58                         array_remove_item(devs->devs, devs->nr, i);
  59                         return;
  60                 }
  61 }
  62
  63 static inline void bch2_dev_list_add_dev(struct bch_devs_list *devs,
  64                                          unsigned dev)
  65 {
  66         if (!bch2_dev_list_has_dev(*devs, dev)) {
  67                 BUG_ON(devs->nr >= ARRAY_SIZE(devs->devs));
  68                 devs->devs[devs->nr++] = dev;
  69         }
  70 }
  71
  72 static inline struct bch_devs_list bch2_dev_list_single(unsigned dev)
  73 {
  74         return (struct bch_devs_list) { .nr = 1, .devs[0] = dev };
  75 }
  76
  77 static inline struct bch_dev *__bch2_next_dev(struct bch_fs *c, unsigned *iter,
  78                                               const struct bch_devs_mask *mask)
  79 {
  80         struct bch_dev *ca = NULL;
  81
  82         while ((*iter = mask
  83                 ? find_next_bit(mask->d, c->sb.nr_devices, *iter)
  84                 : *iter) < c->sb.nr_devices &&
  85                !(ca = rcu_dereference_check(c->devs[*iter],
  86                                             lockdep_is_held(&c->state_lock))))
  87                 (*iter)++;
  88
  89         return ca;
  90 }
  91
  92 #define for_each_member_device_rcu(ca, c, iter, mask)                   \
  93         for ((iter) = 0; ((ca) = __bch2_next_dev((c), &(iter), mask)); (iter)++)
  94
  95 static inline struct bch_dev *bch2_get_next_dev(struct bch_fs *c, unsigned *iter)
  96 {
  97         struct bch_dev *ca;
  98
  99         rcu_read_lock();
 100         if ((ca = __bch2_next_dev(c, iter, NULL)))
 101                 percpu_ref_get(&ca->ref);
 102         rcu_read_unlock();
 103
 104         return ca;
 105 }
 106
 107 /*
 108  * If you break early, you must drop your ref on the current device
 109  */
 110 #define for_each_member_device(ca, c, iter)                             \
 111         for ((iter) = 0;                                                \
 112              (ca = bch2_get_next_dev(c, &(iter)));                      \
 113              percpu_ref_put(&ca->ref), (iter)++)
 114
 115 static inline struct bch_dev *bch2_get_next_online_dev(struct bch_fs *c,
 116                                                       unsigned *iter,
 117                                                       int state_mask)
 118 {
 119         struct bch_dev *ca;
 120
 121         rcu_read_lock();
 122         while ((ca = __bch2_next_dev(c, iter, NULL)) &&
 123                (!((1 << ca->mi.state) & state_mask) ||
 124                 !percpu_ref_tryget(&ca->io_ref)))
 125                 (*iter)++;
 126         rcu_read_unlock();
 127
 128         return ca;
 129 }
 130
 131 #define __for_each_online_member(ca, c, iter, state_mask)               \
 132         for ((iter) = 0;                                                \
 133              (ca = bch2_get_next_online_dev(c, &(iter), state_mask));   \
 134              percpu_ref_put(&ca->io_ref), (iter)++)
 135
 136 #define for_each_online_member(ca, c, iter)                             \
 137         __for_each_online_member(ca, c, iter, ~0)
 138
 139 #define for_each_rw_member(ca, c, iter)                                 \
 140         __for_each_online_member(ca, c, iter, 1 << BCH_MEMBER_STATE_rw)
 141
 142 #define for_each_readable_member(ca, c, iter)                           \
 143         __for_each_online_member(ca, c, iter,                           \
 144                 (1 << BCH_MEMBER_STATE_rw)|(1 << BCH_MEMBER_STATE_ro))
 145
 146 /*
 147  * If a key exists that references a device, the device won't be going away and
 148  * we can omit rcu_read_lock():
 149  */
 150 static inline struct bch_dev *bch_dev_bkey_exists(const struct bch_fs *c, unsigned idx)
 151 {
 152         EBUG_ON(idx >= c->sb.nr_devices || !c->devs[idx]);
 153
 154         return rcu_dereference_check(c->devs[idx], 1);
 155 }
 156
 157 static inline struct bch_dev *bch_dev_locked(struct bch_fs *c, unsigned idx)
 158 {
 159         EBUG_ON(idx >= c->sb.nr_devices || !c->devs[idx]);
 160
 161         return rcu_dereference_protected(c->devs[idx],
 162                                          lockdep_is_held(&c->sb_lock) ||
 163                                          lockdep_is_held(&c->state_lock));
 164 }
 165
 166 /* XXX kill, move to struct bch_fs */
 167 static inline struct bch_devs_mask bch2_online_devs(struct bch_fs *c)
 168 {
 169         struct bch_devs_mask devs;
 170         struct bch_dev *ca;
 171         unsigned i;
 172
 173         memset(&devs, 0, sizeof(devs));
 174         for_each_online_member(ca, c, i)
 175                 __set_bit(ca->dev_idx, devs.d);
 176         return devs;
 177 }
 178
 179 extern const struct bch_sb_field_ops bch_sb_field_ops_members_v1;
 180 extern const struct bch_sb_field_ops bch_sb_field_ops_members_v2;
 181
 182 #endif /* _BCACHEFS_SB_MEMBERS_H */