fs/xfs/xfs_trans_priv.h

   1 /*
   2  * Copyright (c) 2000,2002,2005 Silicon Graphics, Inc.
   3  * All Rights Reserved.
   4  *
   5  * This program is free software; you can redistribute it and/or
   6  * modify it under the terms of the GNU General Public License as
   7  * published by the Free Software Foundation.
   8  *
   9  * This program is distributed in the hope that it would be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program; if not, write the Free Software Foundation,
  16  * Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  17  */
  18 #ifndef __XFS_TRANS_PRIV_H__
  19 #define __XFS_TRANS_PRIV_H__
  20
  21 struct xfs_log_item;
  22 struct xfs_log_item_desc;
  23 struct xfs_mount;
  24 struct xfs_trans;
  25
  26 /*
  27  * From xfs_trans_item.c
  28  */
  29 struct xfs_log_item_desc        *xfs_trans_add_item(struct xfs_trans *,
  30                                             struct xfs_log_item *);
  31 void                            xfs_trans_free_item(struct xfs_trans *,
  32                                             struct xfs_log_item_desc *);
  33 struct xfs_log_item_desc        *xfs_trans_find_item(struct xfs_trans *,
  34                                              struct xfs_log_item *);
  35 struct xfs_log_item_desc        *xfs_trans_first_item(struct xfs_trans *);
  36 struct xfs_log_item_desc        *xfs_trans_next_item(struct xfs_trans *,
  37                                              struct xfs_log_item_desc *);
  38
  39 void    xfs_trans_unlock_items(struct xfs_trans *tp, xfs_lsn_t commit_lsn);
  40 void    xfs_trans_free_items(struct xfs_trans *tp, xfs_lsn_t commit_lsn,
  41                                 int flags);
  42
  43 void    xfs_trans_item_committed(struct xfs_log_item *lip,
  44                                 xfs_lsn_t commit_lsn, int aborted);
  45 void    xfs_trans_unreserve_and_mod_sb(struct xfs_trans *tp);
  46
  47 /*
  48  * AIL traversal cursor.
  49  *
  50  * Rather than using a generation number for detecting changes in the ail, use
  51  * a cursor that is protected by the ail lock. The aild cursor exists in the
  52  * struct xfs_ail, but other traversals can declare it on the stack and link it
  53  * to the ail list.
  54  *
  55  * When an object is deleted from or moved int the AIL, the cursor list is
  56  * searched to see if the object is a designated cursor item. If it is, it is
  57  * deleted from the cursor so that the next time the cursor is used traversal
  58  * will return to the start.
  59  *
  60  * This means a traversal colliding with a removal will cause a restart of the
  61  * list scan, rather than any insertion or deletion anywhere in the list. The
  62  * low bit of the item pointer is set if the cursor has been invalidated so
  63  * that we can tell the difference between invalidation and reaching the end
  64  * of the list to trigger traversal restarts.
  65  */
  66 struct xfs_ail_cursor {
  67         struct xfs_ail_cursor   *next;
  68         struct xfs_log_item     *item;
  69 };
  70
  71 /*
  72  * Private AIL structures.
  73  *
  74  * Eventually we need to drive the locking in here as well.
  75  */
  76 struct xfs_ail {
  77         struct xfs_mount        *xa_mount;
  78         struct list_head        xa_ail;
  79         uint                    xa_gen;
  80         struct task_struct      *xa_task;
  81         xfs_lsn_t               xa_target;
  82         struct xfs_ail_cursor   xa_cursors;
  83         spinlock_t              xa_lock;
  84 };
  85
  86 /*
  87  * From xfs_trans_ail.c
  88  */
  89 void                    xfs_trans_ail_update(struct xfs_ail *ailp,
  90                                         struct xfs_log_item *lip, xfs_lsn_t lsn)
  91                                         __releases(ailp->xa_lock);
  92 void                    xfs_trans_ail_delete(struct xfs_ail *ailp,
  93                                         struct xfs_log_item *lip)
  94                                         __releases(ailp->xa_lock);
  95 void                    xfs_trans_ail_push(struct xfs_ail *, xfs_lsn_t);
  96 void                    xfs_trans_unlocked_item(struct xfs_ail *,
  97                                         xfs_log_item_t *);
  98
  99 xfs_lsn_t               xfs_trans_ail_tail(struct xfs_ail *ailp);
 100
 101 struct xfs_log_item     *xfs_trans_ail_cursor_first(struct xfs_ail *ailp,
 102                                         struct xfs_ail_cursor *cur,
 103                                         xfs_lsn_t lsn);
 104 struct xfs_log_item     *xfs_trans_ail_cursor_next(struct xfs_ail *ailp,
 105                                         struct xfs_ail_cursor *cur);
 106 void                    xfs_trans_ail_cursor_done(struct xfs_ail *ailp,
 107                                         struct xfs_ail_cursor *cur);
 108
 109 long    xfsaild_push(struct xfs_ail *, xfs_lsn_t *);
 110 void    xfsaild_wakeup(struct xfs_ail *, xfs_lsn_t);
 111 int     xfsaild_start(struct xfs_ail *);
 112 void    xfsaild_stop(struct xfs_ail *);
 113
 114 #if BITS_PER_LONG != 64
 115 static inline void
 116 xfs_trans_ail_copy_lsn(
 117         struct xfs_ail  *ailp,
 118         xfs_lsn_t       *dst,
 119         xfs_lsn_t       *src)
 120 {
 121         ASSERT(sizeof(xfs_lsn_t) == 8); /* don't lock if it shrinks */
 122         spin_lock(&ailp->xa_lock);
 123         *dst = *src;
 124         spin_unlock(&ailp->xa_lock);
 125 }
 126 #else
 127 static inline void
 128 xfs_trans_ail_copy_lsn(
 129         struct xfs_ail  *ailp,
 130         xfs_lsn_t       *dst,
 131         xfs_lsn_t       *src)
 132 {
 133         ASSERT(sizeof(xfs_lsn_t) == 8);
 134         *dst = *src;
 135 }
 136 #endif
 137 #endif  /* __XFS_TRANS_PRIV_H__ */