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