}
/*
- * Sort the log items in the transaction. Cancelled buffers need
- * to be put first so they are processed before any items that might
- * modify the buffers. If they are cancelled, then the modifications
- * don't need to be replayed.
+ * Sort the log items in the transaction.
+ *
+ * The ordering constraints are defined by the inode allocation and unlink
+ * behaviour. The rules are:
+ *
+ * 1. Every item is only logged once in a given transaction. Hence it
+ * represents the last logged state of the item. Hence ordering is
+ * dependent on the order in which operations need to be performed so
+ * required initial conditions are always met.
+ *
+ * 2. Cancelled buffers are recorded in pass 1 in a separate table and
+ * there's nothing to replay from them so we can simply cull them
+ * from the transaction. However, we can't do that until after we've
+ * replayed all the other items because they may be dependent on the
+ * cancelled buffer and replaying the cancelled buffer can remove it
+ * form the cancelled buffer table. Hence they have tobe done last.
+ *
+ * 3. Inode allocation buffers must be replayed before inode items that
+ * read the buffer and replay changes into it.
+ *
+ * 4. Inode unlink buffers must be replayed after inode items are replayed.
+ * This ensures that inodes are completely flushed to the inode buffer
+ * in a "free" state before we remove the unlinked inode list pointer.
+ *
+ * Hence the ordering needs to be inode allocation buffers first, inode items
+ * second, inode unlink buffers third and cancelled buffers last.
+ *
+ * But there's a problem with that - we can't tell an inode allocation buffer
+ * apart from a regular buffer, so we can't separate them. We can, however,
+ * tell an inode unlink buffer from the others, and so we can separate them out
+ * from all the other buffers and move them to last.
+ *
+ * Hence, 4 lists, in order from head to tail:
+ * - buffer_list for all buffers except cancelled/inode unlink buffers
+ * - item_list for all non-buffer items
+ * - inode_buffer_list for inode unlink buffers
+ * - cancel_list for the cancelled buffers
*/
STATIC int
xlog_recover_reorder_trans(
{
xlog_recover_item_t *item, *n;
LIST_HEAD(sort_list);
+ LIST_HEAD(cancel_list);
+ LIST_HEAD(buffer_list);
+ LIST_HEAD(inode_buffer_list);
+ LIST_HEAD(inode_list);
list_splice_init(&trans->r_itemq, &sort_list);
list_for_each_entry_safe(item, n, &sort_list, ri_list) {
switch (ITEM_TYPE(item)) {
case XFS_LI_BUF:
- if (!(buf_f->blf_flags & XFS_BLF_CANCEL)) {
+ if (buf_f->blf_flags & XFS_BLF_CANCEL) {
trace_xfs_log_recover_item_reorder_head(log,
trans, item, pass);
- list_move(&item->ri_list, &trans->r_itemq);
+ list_move(&item->ri_list, &cancel_list);
+ break;
+ }
+ if (buf_f->blf_flags & XFS_BLF_INODE_BUF) {
+ list_move(&item->ri_list, &inode_buffer_list);
break;
}
+ list_move_tail(&item->ri_list, &buffer_list);
+ break;
case XFS_LI_INODE:
case XFS_LI_DQUOT:
case XFS_LI_QUOTAOFF:
case XFS_LI_EFI:
trace_xfs_log_recover_item_reorder_tail(log,
trans, item, pass);
- list_move_tail(&item->ri_list, &trans->r_itemq);
+ list_move_tail(&item->ri_list, &inode_list);
break;
default:
xfs_warn(log->l_mp,
}
}
ASSERT(list_empty(&sort_list));
+ if (!list_empty(&buffer_list))
+ list_splice(&buffer_list, &trans->r_itemq);
+ if (!list_empty(&inode_list))
+ list_splice_tail(&inode_list, &trans->r_itemq);
+ if (!list_empty(&inode_buffer_list))
+ list_splice_tail(&inode_buffer_list, &trans->r_itemq);
+ if (!list_empty(&cancel_list))
+ list_splice_tail(&cancel_list, &trans->r_itemq);
return 0;
}
xfs_agino_t *buffer_nextp;
trace_xfs_log_recover_buf_inode_buf(mp->m_log, buf_f);
- bp->b_ops = &xfs_inode_buf_ops;
+
+ /*
+ * Post recovery validation only works properly on CRC enabled
+ * filesystems.
+ */
+ if (xfs_sb_version_hascrc(&mp->m_sb))
+ bp->b_ops = &xfs_inode_buf_ops;
inodes_per_buf = BBTOB(bp->b_io_length) >> mp->m_sb.sb_inodelog;
for (i = 0; i < inodes_per_buf; i++) {
buffer_nextp = (xfs_agino_t *)xfs_buf_offset(bp,
next_unlinked_offset);
*buffer_nextp = *logged_nextp;
+
+ /*
+ * If necessary, recalculate the CRC in the on-disk inode. We
+ * have to leave the inode in a consistent state for whoever
+ * reads it next....
+ */
+ xfs_dinode_calc_crc(mp, (struct xfs_dinode *)
+ xfs_buf_offset(bp, i * mp->m_sb.sb_inodesize));
+
}
return 0;
ASSERT(BBTOB(bp->b_io_length) >=
((uint)bit << XFS_BLF_SHIFT) + (nbits << XFS_BLF_SHIFT));
+ /*
+ * The dirty regions logged in the buffer, even though
+ * contiguous, may span multiple chunks. This is because the
+ * dirty region may span a physical page boundary in a buffer
+ * and hence be split into two separate vectors for writing into
+ * the log. Hence we need to trim nbits back to the length of
+ * the current region being copied out of the log.
+ */
+ if (item->ri_buf[i].i_len < (nbits << XFS_BLF_SHIFT))
+ nbits = item->ri_buf[i].i_len >> XFS_BLF_SHIFT;
+
/*
* Do a sanity check if this is a dquot buffer. Just checking
* the first dquot in the buffer should do. XXXThis is
/* Shouldn't be any more regions */
ASSERT(i == item->ri_total);
- xlog_recovery_validate_buf_type(mp, bp, buf_f);
+ /*
+ * We can only do post recovery validation on items on CRC enabled
+ * fielsystems as we need to know when the buffer was written to be able
+ * to determine if we should have replayed the item. If we replay old
+ * metadata over a newer buffer, then it will enter a temporarily
+ * inconsistent state resulting in verification failures. Hence for now
+ * just avoid the verification stage for non-crc filesystems
+ */
+ if (xfs_sb_version_hascrc(&mp->m_sb))
+ xlog_recovery_validate_buf_type(mp, bp, buf_f);
}
/*
d->dd_diskdq.d_flags = type;
d->dd_diskdq.d_id = cpu_to_be32(id);
+ if (xfs_sb_version_hascrc(&mp->m_sb)) {
+ uuid_copy(&d->dd_uuid, &mp->m_sb.sb_uuid);
+ xfs_update_cksum((char *)d, sizeof(struct xfs_dqblk),
+ XFS_DQUOT_CRC_OFF);
+ }
+
return errs;
}
}
memcpy(ddq, recddq, item->ri_buf[1].i_len);
+ if (xfs_sb_version_hascrc(&mp->m_sb)) {
+ xfs_update_cksum((char *)ddq, sizeof(struct xfs_dqblk),
+ XFS_DQUOT_CRC_OFF);
+ }
ASSERT(dq_f->qlf_size == 2);
ASSERT(bp->b_target->bt_mount == mp);
projects / firefly-linux-kernel-4.4.55.git / blobdiff