LXR linux/fs/xfs/xfs_trans

   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
  21struct xfs_log_item;
  22struct xfs_log_item_desc;
  23struct xfs_mount;
  24struct xfs_trans;
  25struct xfs_ail;
  26struct xfs_log_vec;
  27
  28void    xfs_trans_add_item(struct xfs_trans *, struct xfs_log_item *);
  29void    xfs_trans_del_item(struct xfs_log_item *);
  30void    xfs_trans_free_items(struct xfs_trans *tp, xfs_lsn_t commit_lsn,
  31                                int flags);
  32void    xfs_trans_unreserve_and_mod_sb(struct xfs_trans *tp);
  33
  34void    xfs_trans_committed_bulk(struct xfs_ail *ailp, struct xfs_log_vec *lv,
  35                                xfs_lsn_t commit_lsn, int aborted);
  36/*
  37 * AIL traversal cursor.
  38 *
  39 * Rather than using a generation number for detecting changes in the ail, use
  40 * a cursor that is protected by the ail lock. The aild cursor exists in the
  41 * struct xfs_ail, but other traversals can declare it on the stack and link it
  42 * to the ail list.
  43 *
  44 * When an object is deleted from or moved int the AIL, the cursor list is
  45 * searched to see if the object is a designated cursor item. If it is, it is
  46 * deleted from the cursor so that the next time the cursor is used traversal
  47 * will return to the start.
  48 *
  49 * This means a traversal colliding with a removal will cause a restart of the
  50 * list scan, rather than any insertion or deletion anywhere in the list. The
  51 * low bit of the item pointer is set if the cursor has been invalidated so
  52 * that we can tell the difference between invalidation and reaching the end
  53 * of the list to trigger traversal restarts.
  54 */
  55struct xfs_ail_cursor {
  56        struct list_head        list;
  57        struct xfs_log_item     *item;
  58};
  59
  60/*
  61 * Private AIL structures.
  62 *
  63 * Eventually we need to drive the locking in here as well.
  64 */
  65struct xfs_ail {
  66        struct xfs_mount        *xa_mount;
  67        struct task_struct      *xa_task;
  68        struct list_head        xa_ail;
  69        xfs_lsn_t               xa_target;
  70        struct list_head        xa_cursors;
  71        spinlock_t              xa_lock;
  72        xfs_lsn_t               xa_last_pushed_lsn;
  73};
  74
  75/*
  76 * From xfs_trans_ail.c
  77 */
  78void    xfs_trans_ail_update_bulk(struct xfs_ail *ailp,
  79                                struct xfs_ail_cursor *cur,
  80                                struct xfs_log_item **log_items, int nr_items,
  81                                xfs_lsn_t lsn) __releases(ailp->xa_lock);
  82static inline void
  83xfs_trans_ail_update(
  84        struct xfs_ail          *ailp,
  85        struct xfs_log_item     *lip,
  86        xfs_lsn_t               lsn) __releases(ailp->xa_lock)
  87{
  88        xfs_trans_ail_update_bulk(ailp, NULL, &lip, 1, lsn);
  89}
  90
  91void    xfs_trans_ail_delete_bulk(struct xfs_ail *ailp,
  92                                struct xfs_log_item **log_items, int nr_items)
  93                                __releases(ailp->xa_lock);
  94static inline void
  95xfs_trans_ail_delete(
  96        struct xfs_ail  *ailp,
  97        xfs_log_item_t  *lip) __releases(ailp->xa_lock)
  98{
  99        xfs_trans_ail_delete_bulk(ailp, &lip, 1);
 100}
 101
 102void                    xfs_ail_push(struct xfs_ail *, xfs_lsn_t);
 103void                    xfs_ail_push_all(struct xfs_ail *);
 104xfs_lsn_t               xfs_ail_min_lsn(struct xfs_ail *ailp);
 105
 106void                    xfs_trans_unlocked_item(struct xfs_ail *,
 107                                        xfs_log_item_t *);
 108
 109struct xfs_log_item *   xfs_trans_ail_cursor_first(struct xfs_ail *ailp,
 110                                        struct xfs_ail_cursor *cur,
 111                                        xfs_lsn_t lsn);
 112struct xfs_log_item *   xfs_trans_ail_cursor_last(struct xfs_ail *ailp,
 113                                        struct xfs_ail_cursor *cur,
 114                                        xfs_lsn_t lsn);
 115struct xfs_log_item *   xfs_trans_ail_cursor_next(struct xfs_ail *ailp,
 116                                        struct xfs_ail_cursor *cur);
 117void                    xfs_trans_ail_cursor_done(struct xfs_ail *ailp,
 118                                        struct xfs_ail_cursor *cur);
 119
 120#if BITS_PER_LONG != 64
 121static inline void
 122xfs_trans_ail_copy_lsn(
 123        struct xfs_ail  *ailp,
 124        xfs_lsn_t       *dst,
 125        xfs_lsn_t       *src)
 126{
 127        ASSERT(sizeof(xfs_lsn_t) == 8); /* don't lock if it shrinks */
 128        spin_lock(&ailp->xa_lock);
 129        *dst = *src;
 130        spin_unlock(&ailp->xa_lock);
 131}
 132#else
 133static inline void
 134xfs_trans_ail_copy_lsn(
 135        struct xfs_ail  *ailp,
 136        xfs_lsn_t       *dst,
 137        xfs_lsn_t       *src)
 138{
 139        ASSERT(sizeof(xfs_lsn_t) == 8);
 140        *dst = *src;
 141}
 142#endif
 143#endif  /* __XFS_TRANS_PRIV_H__ */
 144