LXR linux/fs/xfs/xfs

   1/*
   2 * Copyright (c) 2000-2003,2005 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_LOG_H__
  19#define __XFS_LOG_H__
  20
  21struct xfs_log_vec {
  22        struct xfs_log_vec      *lv_next;       /* next lv in build list */
  23        int                     lv_niovecs;     /* number of iovecs in lv */
  24        struct xfs_log_iovec    *lv_iovecp;     /* iovec array */
  25        struct xfs_log_item     *lv_item;       /* owner */
  26        char                    *lv_buf;        /* formatted buffer */
  27        int                     lv_bytes;       /* accounted space in buffer */
  28        int                     lv_buf_len;     /* aligned size of buffer */
  29        int                     lv_size;        /* size of allocated lv */
  30};
  31
  32#define XFS_LOG_VEC_ORDERED     (-1)
  33
  34static inline void *
  35xlog_prepare_iovec(struct xfs_log_vec *lv, struct xfs_log_iovec **vecp,
  36                uint type)
  37{
  38        struct xfs_log_iovec *vec = *vecp;
  39
  40        if (vec) {
  41                ASSERT(vec - lv->lv_iovecp < lv->lv_niovecs);
  42                vec++;
  43        } else {
  44                vec = &lv->lv_iovecp[0];
  45        }
  46
  47        vec->i_type = type;
  48        vec->i_addr = lv->lv_buf + lv->lv_buf_len;
  49
  50        ASSERT(IS_ALIGNED((unsigned long)vec->i_addr, sizeof(uint64_t)));
  51
  52        *vecp = vec;
  53        return vec->i_addr;
  54}
  55
  56/*
  57 * We need to make sure the next buffer is naturally aligned for the biggest
  58 * basic data type we put into it.  We already accounted for this padding when
  59 * sizing the buffer.
  60 *
  61 * However, this padding does not get written into the log, and hence we have to
  62 * track the space used by the log vectors separately to prevent log space hangs
  63 * due to inaccurate accounting (i.e. a leak) of the used log space through the
  64 * CIL context ticket.
  65 */
  66static inline void
  67xlog_finish_iovec(struct xfs_log_vec *lv, struct xfs_log_iovec *vec, int len)
  68{
  69        lv->lv_buf_len += round_up(len, sizeof(uint64_t));
  70        lv->lv_bytes += len;
  71        vec->i_len = len;
  72}
  73
  74static inline void *
  75xlog_copy_iovec(struct xfs_log_vec *lv, struct xfs_log_iovec **vecp,
  76                uint type, void *data, int len)
  77{
  78        void *buf;
  79
  80        buf = xlog_prepare_iovec(lv, vecp, type);
  81        memcpy(buf, data, len);
  82        xlog_finish_iovec(lv, *vecp, len);
  83        return buf;
  84}
  85
  86/*
  87 * Structure used to pass callback function and the function's argument
  88 * to the log manager.
  89 */
  90typedef struct xfs_log_callback {
  91        struct xfs_log_callback *cb_next;
  92        void                    (*cb_func)(void *, int);
  93        void                    *cb_arg;
  94} xfs_log_callback_t;
  95
  96/*
  97 * By comparing each component, we don't have to worry about extra
  98 * endian issues in treating two 32 bit numbers as one 64 bit number
  99 */
 100static inline xfs_lsn_t _lsn_cmp(xfs_lsn_t lsn1, xfs_lsn_t lsn2)
 101{
 102        if (CYCLE_LSN(lsn1) != CYCLE_LSN(lsn2))
 103                return (CYCLE_LSN(lsn1)<CYCLE_LSN(lsn2))? -999 : 999;
 104
 105        if (BLOCK_LSN(lsn1) != BLOCK_LSN(lsn2))
 106                return (BLOCK_LSN(lsn1)<BLOCK_LSN(lsn2))? -999 : 999;
 107
 108        return 0;
 109}
 110
 111#define XFS_LSN_CMP(x,y) _lsn_cmp(x,y)
 112
 113/*
 114 * Flags to xfs_log_force()
 115 *
 116 *      XFS_LOG_SYNC:   Synchronous force in-core log to disk
 117 */
 118#define XFS_LOG_SYNC            0x1
 119
 120/* Log manager interfaces */
 121struct xfs_mount;
 122struct xlog_in_core;
 123struct xlog_ticket;
 124struct xfs_log_item;
 125struct xfs_item_ops;
 126struct xfs_trans;
 127
 128xfs_lsn_t xfs_log_done(struct xfs_mount *mp,
 129                       struct xlog_ticket *ticket,
 130                       struct xlog_in_core **iclog,
 131                       bool regrant);
 132int       _xfs_log_force(struct xfs_mount *mp,
 133                         uint           flags,
 134                         int            *log_forced);
 135void      xfs_log_force(struct xfs_mount        *mp,
 136                        uint                    flags);
 137int       _xfs_log_force_lsn(struct xfs_mount *mp,
 138                             xfs_lsn_t          lsn,
 139                             uint               flags,
 140                             int                *log_forced);
 141void      xfs_log_force_lsn(struct xfs_mount    *mp,
 142                            xfs_lsn_t           lsn,
 143                            uint                flags);
 144int       xfs_log_mount(struct xfs_mount        *mp,
 145                        struct xfs_buftarg      *log_target,
 146                        xfs_daddr_t             start_block,
 147                        int                     num_bblocks);
 148int       xfs_log_mount_finish(struct xfs_mount *mp);
 149int     xfs_log_mount_cancel(struct xfs_mount *);
 150xfs_lsn_t xlog_assign_tail_lsn(struct xfs_mount *mp);
 151xfs_lsn_t xlog_assign_tail_lsn_locked(struct xfs_mount *mp);
 152void      xfs_log_space_wake(struct xfs_mount *mp);
 153int       xfs_log_notify(struct xfs_mount       *mp,
 154                         struct xlog_in_core    *iclog,
 155                         struct xfs_log_callback *callback_entry);
 156int       xfs_log_release_iclog(struct xfs_mount *mp,
 157                         struct xlog_in_core     *iclog);
 158int       xfs_log_reserve(struct xfs_mount *mp,
 159                          int              length,
 160                          int              count,
 161                          struct xlog_ticket **ticket,
 162                          uint8_t                  clientid,
 163                          bool             permanent);
 164int       xfs_log_regrant(struct xfs_mount *mp, struct xlog_ticket *tic);
 165void      xfs_log_unmount(struct xfs_mount *mp);
 166int       xfs_log_force_umount(struct xfs_mount *mp, int logerror);
 167
 168struct xlog_ticket *xfs_log_ticket_get(struct xlog_ticket *ticket);
 169void      xfs_log_ticket_put(struct xlog_ticket *ticket);
 170
 171void    xfs_log_commit_cil(struct xfs_mount *mp, struct xfs_trans *tp,
 172                                xfs_lsn_t *commit_lsn, bool regrant);
 173bool    xfs_log_item_in_current_chkpt(struct xfs_log_item *lip);
 174
 175void    xfs_log_work_queue(struct xfs_mount *mp);
 176void    xfs_log_quiesce(struct xfs_mount *mp);
 177bool    xfs_log_check_lsn(struct xfs_mount *, xfs_lsn_t);
 178
 179#endif  /* __XFS_LOG_H__ */
 180