fs/xfs/xfs_trans_priv.h

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Copyright (c) 2000,2002,2005 Silicon Graphics, Inc.
   4  * All Rights Reserved.
   5  */
   6 #ifndef __XFS_TRANS_PRIV_H__
   7 #define __XFS_TRANS_PRIV_H__
   8
   9 struct xlog;
  10 struct xfs_log_item;
  11 struct xfs_mount;
  12 struct xfs_trans;
  13 struct xfs_ail;
  14 struct xfs_log_vec;
  15
  16
  17 void    xfs_trans_init(struct xfs_mount *);
  18 void    xfs_trans_add_item(struct xfs_trans *, struct xfs_log_item *);
  19 void    xfs_trans_del_item(struct xfs_log_item *);
  20 void    xfs_trans_unreserve_and_mod_sb(struct xfs_trans *tp);
  21
  22 /*
  23  * AIL traversal cursor.
  24  *
  25  * Rather than using a generation number for detecting changes in the ail, use
  26  * a cursor that is protected by the ail lock. The aild cursor exists in the
  27  * struct xfs_ail, but other traversals can declare it on the stack and link it
  28  * to the ail list.
  29  *
  30  * When an object is deleted from or moved int the AIL, the cursor list is
  31  * searched to see if the object is a designated cursor item. If it is, it is
  32  * deleted from the cursor so that the next time the cursor is used traversal
  33  * will return to the start.
  34  *
  35  * This means a traversal colliding with a removal will cause a restart of the
  36  * list scan, rather than any insertion or deletion anywhere in the list. The
  37  * low bit of the item pointer is set if the cursor has been invalidated so
  38  * that we can tell the difference between invalidation and reaching the end
  39  * of the list to trigger traversal restarts.
  40  */
  41 struct xfs_ail_cursor {
  42         struct list_head        list;
  43         struct xfs_log_item     *item;
  44 };
  45
  46 /*
  47  * Private AIL structures.
  48  *
  49  * Eventually we need to drive the locking in here as well.
  50  */
  51 struct xfs_ail {
  52         struct xlog             *ail_log;
  53         struct task_struct      *ail_task;
  54         struct list_head        ail_head;
  55         struct list_head        ail_cursors;
  56         spinlock_t              ail_lock;
  57         xfs_lsn_t               ail_last_pushed_lsn;
  58         xfs_lsn_t               ail_head_lsn;
  59         int                     ail_log_flush;
  60         unsigned long           ail_opstate;
  61         struct list_head        ail_buf_list;
  62         wait_queue_head_t       ail_empty;
  63         xfs_lsn_t               ail_target;
  64 };
  65
  66 /* Push all items out of the AIL immediately. */
  67 #define XFS_AIL_OPSTATE_PUSH_ALL        0u
  68
  69 /*
  70  * From xfs_trans_ail.c
  71  */
  72 void    xfs_trans_ail_update_bulk(struct xfs_ail *ailp,
  73                                 struct xfs_ail_cursor *cur,
  74                                 struct xfs_log_item **log_items, int nr_items,
  75                                 xfs_lsn_t lsn) __releases(ailp->ail_lock);
  76 /*
  77  * Return a pointer to the first item in the AIL.  If the AIL is empty, then
  78  * return NULL.
  79  */
  80 static inline struct xfs_log_item *
  81 xfs_ail_min(
  82         struct xfs_ail  *ailp)
  83 {
  84         return list_first_entry_or_null(&ailp->ail_head, struct xfs_log_item,
  85                                         li_ail);
  86 }
  87
  88 static inline void
  89 xfs_trans_ail_update(
  90         struct xfs_ail          *ailp,
  91         struct xfs_log_item     *lip,
  92         xfs_lsn_t               lsn) __releases(ailp->ail_lock)
  93 {
  94         xfs_trans_ail_update_bulk(ailp, NULL, &lip, 1, lsn);
  95 }
  96
  97 void xfs_trans_ail_insert(struct xfs_ail *ailp, struct xfs_log_item *lip,
  98                 xfs_lsn_t lsn);
  99
 100 xfs_lsn_t xfs_ail_delete_one(struct xfs_ail *ailp, struct xfs_log_item *lip);
 101 void xfs_ail_update_finish(struct xfs_ail *ailp, xfs_lsn_t old_lsn)
 102                         __releases(ailp->ail_lock);
 103 void xfs_trans_ail_delete(struct xfs_log_item *lip, int shutdown_type);
 104
 105 static inline void xfs_ail_push(struct xfs_ail *ailp)
 106 {
 107         wake_up_process(ailp->ail_task);
 108 }
 109
 110 static inline void xfs_ail_push_all(struct xfs_ail *ailp)
 111 {
 112         if (!test_and_set_bit(XFS_AIL_OPSTATE_PUSH_ALL, &ailp->ail_opstate))
 113                 xfs_ail_push(ailp);
 114 }
 115
 116 static inline xfs_lsn_t xfs_ail_get_push_target(struct xfs_ail *ailp)
 117 {
 118         return READ_ONCE(ailp->ail_target);
 119 }
 120
 121 void                    xfs_ail_push_all_sync(struct xfs_ail *ailp);
 122 xfs_lsn_t               xfs_ail_min_lsn(struct xfs_ail *ailp);
 123
 124 struct xfs_log_item *   xfs_trans_ail_cursor_first(struct xfs_ail *ailp,
 125                                         struct xfs_ail_cursor *cur,
 126                                         xfs_lsn_t lsn);
 127 struct xfs_log_item *   xfs_trans_ail_cursor_last(struct xfs_ail *ailp,
 128                                         struct xfs_ail_cursor *cur,
 129                                         xfs_lsn_t lsn);
 130 struct xfs_log_item *   xfs_trans_ail_cursor_next(struct xfs_ail *ailp,
 131                                         struct xfs_ail_cursor *cur);
 132 void                    xfs_trans_ail_cursor_done(struct xfs_ail_cursor *cur);
 133
 134 void                    __xfs_ail_assign_tail_lsn(struct xfs_ail *ailp);
 135
 136 static inline void
 137 xfs_ail_assign_tail_lsn(
 138         struct xfs_ail          *ailp)
 139 {
 140
 141         spin_lock(&ailp->ail_lock);
 142         __xfs_ail_assign_tail_lsn(ailp);
 143         spin_unlock(&ailp->ail_lock);
 144 }
 145
 146 #if BITS_PER_LONG != 64
 147 static inline void
 148 xfs_trans_ail_copy_lsn(
 149         struct xfs_ail  *ailp,
 150         xfs_lsn_t       *dst,
 151         xfs_lsn_t       *src)
 152 {
 153         ASSERT(sizeof(xfs_lsn_t) == 8); /* don't lock if it shrinks */
 154         spin_lock(&ailp->ail_lock);
 155         *dst = *src;
 156         spin_unlock(&ailp->ail_lock);
 157 }
 158 #else
 159 static inline void
 160 xfs_trans_ail_copy_lsn(
 161         struct xfs_ail  *ailp,
 162         xfs_lsn_t       *dst,
 163         xfs_lsn_t       *src)
 164 {
 165         ASSERT(sizeof(xfs_lsn_t) == 8);
 166         *dst = *src;
 167 }
 168 #endif
 169
 170 static inline void
 171 xfs_clear_li_failed(
 172         struct xfs_log_item     *lip)
 173 {
 174         struct xfs_buf  *bp = lip->li_buf;
 175
 176         ASSERT(test_bit(XFS_LI_IN_AIL, &lip->li_flags));
 177         lockdep_assert_held(&lip->li_ailp->ail_lock);
 178
 179         if (test_and_clear_bit(XFS_LI_FAILED, &lip->li_flags)) {
 180                 lip->li_buf = NULL;
 181                 xfs_buf_rele(bp);
 182         }
 183 }
 184
 185 static inline void
 186 xfs_set_li_failed(
 187         struct xfs_log_item     *lip,
 188         struct xfs_buf          *bp)
 189 {
 190         lockdep_assert_held(&lip->li_ailp->ail_lock);
 191
 192         if (!test_and_set_bit(XFS_LI_FAILED, &lip->li_flags)) {
 193                 xfs_buf_hold(bp);
 194                 lip->li_buf = bp;
 195         }
 196 }
 197
 198 #endif  /* __XFS_TRANS_PRIV_H__ */