return error;
}
+ /*
+ * We do not hold the inode locked across the entire rolling transaction
+ * here. We only need to hold it for the first transaction that
+ * xfs_ifree() builds, which may mark the inode XFS_ISTALE if the
+ * underlying cluster buffer is freed. Relogging an XFS_ISTALE inode
+ * here breaks the relationship between cluster buffer invalidation and
+ * stale inode invalidation on cluster buffer item journal commit
+ * completion, and can result in leaving dirty stale inodes hanging
+ * around in memory.
+ *
+ * We have no need for serialising this inode operation against other
+ * operations - we freed the inode and hence reallocation is required
+ * and that will serialise on reallocating the space the deferops need
+ * to free. Hence we can unlock the inode on the first commit of
+ * the transaction rather than roll it right through the deferops. This
+ * avoids relogging the XFS_ISTALE inode.
+ *
+ * We check that xfs_ifree() hasn't grown an internal transaction roll
+ * by asserting that the inode is still locked when it returns.
+ */
xfs_ilock(ip, XFS_ILOCK_EXCL);
- xfs_trans_ijoin(tp, ip, 0);
+ xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
error = xfs_ifree(tp, ip);
+ ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
if (error) {
/*
* If we fail to free the inode, shut down. The cancel
xfs_force_shutdown(mp, SHUTDOWN_META_IO_ERROR);
}
xfs_trans_cancel(tp);
- xfs_iunlock(ip, XFS_ILOCK_EXCL);
return error;
}
xfs_notice(mp, "%s: xfs_trans_commit returned error %d",
__func__, error);
- xfs_iunlock(ip, XFS_ILOCK_EXCL);
return 0;
}
}
/*
- * Look up the inode number specified and mark it stale if it is found. If it is
- * dirty, return the inode so it can be attached to the cluster buffer so it can
- * be processed appropriately when the cluster free transaction completes.
+ * Look up the inode number specified and if it is not already marked XFS_ISTALE
+ * mark it stale. We should only find clean inodes in this lookup that aren't
+ * already stale.
*/
-static struct xfs_inode *
-xfs_ifree_get_one_inode(
- struct xfs_perag *pag,
+static void
+xfs_ifree_mark_inode_stale(
+ struct xfs_buf *bp,
struct xfs_inode *free_ip,
xfs_ino_t inum)
{
- struct xfs_mount *mp = pag->pag_mount;
+ struct xfs_mount *mp = bp->b_mount;
+ struct xfs_perag *pag = bp->b_pag;
+ struct xfs_inode_log_item *iip;
struct xfs_inode *ip;
retry:
ip = radix_tree_lookup(&pag->pag_ici_root, XFS_INO_TO_AGINO(mp, inum));
/* Inode not in memory, nothing to do */
- if (!ip)
- goto out_rcu_unlock;
+ if (!ip) {
+ rcu_read_unlock();
+ return;
+ }
/*
* because this is an RCU protected lookup, we could find a recently
spin_lock(&ip->i_flags_lock);
if (ip->i_ino != inum || __xfs_iflags_test(ip, XFS_ISTALE)) {
spin_unlock(&ip->i_flags_lock);
- goto out_rcu_unlock;
+ rcu_read_unlock();
+ return;
}
- spin_unlock(&ip->i_flags_lock);
/*
* Don't try to lock/unlock the current inode, but we _cannot_ skip the
*/
if (ip != free_ip) {
if (!xfs_ilock_nowait(ip, XFS_ILOCK_EXCL)) {
+ spin_unlock(&ip->i_flags_lock);
rcu_read_unlock();
delay(1);
goto retry;
}
-
- /*
- * Check the inode number again in case we're racing with
- * freeing in xfs_reclaim_inode(). See the comments in that
- * function for more information as to why the initial check is
- * not sufficient.
- */
- if (ip->i_ino != inum) {
- xfs_iunlock(ip, XFS_ILOCK_EXCL);
- goto out_rcu_unlock;
- }
}
+ ip->i_flags |= XFS_ISTALE;
+ spin_unlock(&ip->i_flags_lock);
rcu_read_unlock();
- xfs_iflock(ip);
- xfs_iflags_set(ip, XFS_ISTALE);
+ /*
+ * If we can't get the flush lock, the inode is already attached. All
+ * we needed to do here is mark the inode stale so buffer IO completion
+ * will remove it from the AIL.
+ */
+ iip = ip->i_itemp;
+ if (!xfs_iflock_nowait(ip)) {
+ ASSERT(!list_empty(&iip->ili_item.li_bio_list));
+ ASSERT(iip->ili_last_fields);
+ goto out_iunlock;
+ }
/*
- * We don't need to attach clean inodes or those only with unlogged
- * changes (which we throw away, anyway).
+ * Inodes not attached to the buffer can be released immediately.
+ * Everything else has to go through xfs_iflush_abort() on journal
+ * commit as the flock synchronises removal of the inode from the
+ * cluster buffer against inode reclaim.
*/
- if (!ip->i_itemp || xfs_inode_clean(ip)) {
- ASSERT(ip != free_ip);
+ if (!iip || list_empty(&iip->ili_item.li_bio_list)) {
xfs_ifunlock(ip);
- xfs_iunlock(ip, XFS_ILOCK_EXCL);
- goto out_no_inode;
+ goto out_iunlock;
}
- return ip;
-out_rcu_unlock:
- rcu_read_unlock();
-out_no_inode:
- return NULL;
+ /* we have a dirty inode in memory that has not yet been flushed. */
+ spin_lock(&iip->ili_lock);
+ iip->ili_last_fields = iip->ili_fields;
+ iip->ili_fields = 0;
+ iip->ili_fsync_fields = 0;
+ spin_unlock(&iip->ili_lock);
+ ASSERT(iip->ili_last_fields);
+
+out_iunlock:
+ if (ip != free_ip)
+ xfs_iunlock(ip, XFS_ILOCK_EXCL);
}
/*
*/
STATIC int
xfs_ifree_cluster(
- xfs_inode_t *free_ip,
- xfs_trans_t *tp,
+ struct xfs_inode *free_ip,
+ struct xfs_trans *tp,
struct xfs_icluster *xic)
{
- xfs_mount_t *mp = free_ip->i_mount;
+ struct xfs_mount *mp = free_ip->i_mount;
+ struct xfs_ino_geometry *igeo = M_IGEO(mp);
+ struct xfs_buf *bp;
+ xfs_daddr_t blkno;
+ xfs_ino_t inum = xic->first_ino;
int nbufs;
int i, j;
int ioffset;
- xfs_daddr_t blkno;
- xfs_buf_t *bp;
- xfs_inode_t *ip;
- struct xfs_inode_log_item *iip;
- struct xfs_log_item *lip;
- struct xfs_perag *pag;
- struct xfs_ino_geometry *igeo = M_IGEO(mp);
- xfs_ino_t inum;
int error;
- inum = xic->first_ino;
- pag = xfs_perag_get(mp, XFS_INO_TO_AGNO(mp, inum));
nbufs = igeo->ialloc_blks / igeo->blocks_per_cluster;
for (j = 0; j < nbufs; j++, inum += igeo->inodes_per_cluster) {
bp->b_ops = &xfs_inode_buf_ops;
/*
- * Walk the inodes already attached to the buffer and mark them
- * stale. These will all have the flush locks held, so an
- * in-memory inode walk can't lock them. By marking them all
- * stale first, we will not attempt to lock them in the loop
- * below as the XFS_ISTALE flag will be set.
+ * Now we need to set all the cached clean inodes as XFS_ISTALE,
+ * too. This requires lookups, and will skip inodes that we've
+ * already marked XFS_ISTALE.
*/
- list_for_each_entry(lip, &bp->b_li_list, li_bio_list) {
- if (lip->li_type == XFS_LI_INODE) {
- iip = (struct xfs_inode_log_item *)lip;
- ASSERT(iip->ili_logged == 1);
- lip->li_cb = xfs_istale_done;
- xfs_trans_ail_copy_lsn(mp->m_ail,
- &iip->ili_flush_lsn,
- &iip->ili_item.li_lsn);
- xfs_iflags_set(iip->ili_inode, XFS_ISTALE);
- }
- }
-
-
- /*
- * For each inode in memory attempt to add it to the inode
- * buffer and set it up for being staled on buffer IO
- * completion. This is safe as we've locked out tail pushing
- * and flushing by locking the buffer.
- *
- * We have already marked every inode that was part of a
- * transaction stale above, which means there is no point in
- * even trying to lock them.
- */
- for (i = 0; i < igeo->inodes_per_cluster; i++) {
- ip = xfs_ifree_get_one_inode(pag, free_ip, inum + i);
- if (!ip)
- continue;
-
- iip = ip->i_itemp;
- iip->ili_last_fields = iip->ili_fields;
- iip->ili_fields = 0;
- iip->ili_fsync_fields = 0;
- iip->ili_logged = 1;
- xfs_trans_ail_copy_lsn(mp->m_ail, &iip->ili_flush_lsn,
- &iip->ili_item.li_lsn);
-
- xfs_buf_attach_iodone(bp, xfs_istale_done,
- &iip->ili_item);
-
- if (ip != free_ip)
- xfs_iunlock(ip, XFS_ILOCK_EXCL);
- }
+ for (i = 0; i < igeo->inodes_per_cluster; i++)
+ xfs_ifree_mark_inode_stale(bp, free_ip, inum + i);
xfs_trans_stale_inode_buf(tp, bp);
xfs_trans_binval(tp, bp);
}
-
- xfs_perag_put(pag);
return 0;
}
{
int error;
struct xfs_icluster xic = { 0 };
+ struct xfs_inode_log_item *iip = ip->i_itemp;
ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
ASSERT(VFS_I(ip)->i_nlink == 0);
ip->i_df.if_format = XFS_DINODE_FMT_EXTENTS;
/* Don't attempt to replay owner changes for a deleted inode */
- ip->i_itemp->ili_fields &= ~(XFS_ILOG_AOWNER|XFS_ILOG_DOWNER);
+ spin_lock(&iip->ili_lock);
+ iip->ili_fields &= ~(XFS_ILOG_AOWNER | XFS_ILOG_DOWNER);
+ spin_unlock(&iip->ili_lock);
/*
* Bump the generation count so no one will be confused
* know that the information those bits represent is permanently on
* disk. As long as the flush completes before the inode is logged
* again, then both ili_fields and ili_last_fields will be cleared.
- *
- * We can play with the ili_fields bits here, because the inode lock
- * must be held exclusively in order to set bits there and the flush
- * lock protects the ili_last_fields bits. Set ili_logged so the flush
- * done routine can tell whether or not to look in the AIL. Also, store
- * the current LSN of the inode so that we can tell whether the item has
- * moved in the AIL from xfs_iflush_done(). In order to read the lsn we
- * need the AIL lock, because it is a 64 bit value that cannot be read
- * atomically.
*/
error = 0;
flush_out:
+ spin_lock(&iip->ili_lock);
iip->ili_last_fields = iip->ili_fields;
iip->ili_fields = 0;
iip->ili_fsync_fields = 0;
- iip->ili_logged = 1;
-
- xfs_trans_ail_copy_lsn(mp->m_ail, &iip->ili_flush_lsn,
- &iip->ili_item.li_lsn);
+ spin_unlock(&iip->ili_lock);
/*
- * Attach the inode item callback to the buffer whether the flush
- * succeeded or not. If not, the caller will shut down and fail I/O
- * completion on the buffer to remove the inode from the AIL and release
- * the flush lock.
+ * Store the current LSN of the inode so that we can tell whether the
+ * item has moved in the AIL from xfs_iflush_done().
*/
- xfs_buf_attach_iodone(bp, xfs_iflush_done, &iip->ili_item);
+ xfs_trans_ail_copy_lsn(mp->m_ail, &iip->ili_flush_lsn,
+ &iip->ili_item.li_lsn);
/* generate the checksum. */
xfs_dinode_calc_crc(mp, dip);
-
- ASSERT(!list_empty(&bp->b_li_list));
- ASSERT(bp->b_iodone != NULL);
return error;
}
return 0;
return xfs_log_force_lsn(ip->i_mount, lsn, XFS_LOG_SYNC, NULL);
}
+
+/*
+ * Grab the exclusive iolock for a data copy from src to dest, making sure to
+ * abide vfs locking order (lowest pointer value goes first) and breaking the
+ * layout leases before proceeding. The loop is needed because we cannot call
+ * the blocking break_layout() with the iolocks held, and therefore have to
+ * back out both locks.
+ */
+static int
+xfs_iolock_two_inodes_and_break_layout(
+ struct inode *src,
+ struct inode *dest)
+{
+ int error;
+
+ if (src > dest)
+ swap(src, dest);
+
+retry:
+ /* Wait to break both inodes' layouts before we start locking. */
+ error = break_layout(src, true);
+ if (error)
+ return error;
+ if (src != dest) {
+ error = break_layout(dest, true);
+ if (error)
+ return error;
+ }
+
+ /* Lock one inode and make sure nobody got in and leased it. */
+ inode_lock(src);
+ error = break_layout(src, false);
+ if (error) {
+ inode_unlock(src);
+ if (error == -EWOULDBLOCK)
+ goto retry;
+ return error;
+ }
+
+ if (src == dest)
+ return 0;
+
+ /* Lock the other inode and make sure nobody got in and leased it. */
+ inode_lock_nested(dest, I_MUTEX_NONDIR2);
+ error = break_layout(dest, false);
+ if (error) {
+ inode_unlock(src);
+ inode_unlock(dest);
+ if (error == -EWOULDBLOCK)
+ goto retry;
+ return error;
+ }
+
+ return 0;
+}
+
+/*
+ * Lock two inodes so that userspace cannot initiate I/O via file syscalls or
+ * mmap activity.
+ */
+int
+xfs_ilock2_io_mmap(
+ struct xfs_inode *ip1,
+ struct xfs_inode *ip2)
+{
+ int ret;
+
+ ret = xfs_iolock_two_inodes_and_break_layout(VFS_I(ip1), VFS_I(ip2));
+ if (ret)
+ return ret;
+ if (ip1 == ip2)
+ xfs_ilock(ip1, XFS_MMAPLOCK_EXCL);
+ else
+ xfs_lock_two_inodes(ip1, XFS_MMAPLOCK_EXCL,
+ ip2, XFS_MMAPLOCK_EXCL);
+ return 0;
+}
+
+/* Unlock both inodes to allow IO and mmap activity. */
+void
+xfs_iunlock2_io_mmap(
+ struct xfs_inode *ip1,
+ struct xfs_inode *ip2)
+{
+ bool same_inode = (ip1 == ip2);
+
+ xfs_iunlock(ip2, XFS_MMAPLOCK_EXCL);
+ if (!same_inode)
+ xfs_iunlock(ip1, XFS_MMAPLOCK_EXCL);
+ inode_unlock(VFS_I(ip2));
+ if (!same_inode)
+ inode_unlock(VFS_I(ip1));
+}
projects / linux-2.6-microblaze.git / blobdiff