forked from Minki/linux
fa0d7e3de6
RCU free the struct inode. This will allow: - Subsequent store-free path walking patch. The inode must be consulted for permissions when walking, so an RCU inode reference is a must. - sb_inode_list_lock to be moved inside i_lock because sb list walkers who want to take i_lock no longer need to take sb_inode_list_lock to walk the list in the first place. This will simplify and optimize locking. - Could remove some nested trylock loops in dcache code - Could potentially simplify things a bit in VM land. Do not need to take the page lock to follow page->mapping. The downsides of this is the performance cost of using RCU. In a simple creat/unlink microbenchmark, performance drops by about 10% due to inability to reuse cache-hot slab objects. As iterations increase and RCU freeing starts kicking over, this increases to about 20%. In cases where inode lifetimes are longer (ie. many inodes may be allocated during the average life span of a single inode), a lot of this cache reuse is not applicable, so the regression caused by this patch is smaller. The cache-hot regression could largely be avoided by using SLAB_DESTROY_BY_RCU, however this adds some complexity to list walking and store-free path walking, so I prefer to implement this at a later date, if it is shown to be a win in real situations. I haven't found a regression in any non-micro benchmark so I doubt it will be a problem. Signed-off-by: Nick Piggin <npiggin@kernel.dk>
674 lines
18 KiB
C
674 lines
18 KiB
C
/*
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* Copyright (c) 2000-2005 Silicon Graphics, Inc.
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* All Rights Reserved.
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License as
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* published by the Free Software Foundation.
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*
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* This program is distributed in the hope that it would be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write the Free Software Foundation,
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* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
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*/
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#include "xfs.h"
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#include "xfs_fs.h"
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#include "xfs_types.h"
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#include "xfs_acl.h"
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#include "xfs_bit.h"
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#include "xfs_log.h"
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#include "xfs_inum.h"
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#include "xfs_trans.h"
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#include "xfs_sb.h"
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#include "xfs_ag.h"
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#include "xfs_mount.h"
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#include "xfs_bmap_btree.h"
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#include "xfs_alloc_btree.h"
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#include "xfs_ialloc_btree.h"
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#include "xfs_dinode.h"
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#include "xfs_inode.h"
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#include "xfs_btree.h"
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#include "xfs_ialloc.h"
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#include "xfs_quota.h"
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#include "xfs_utils.h"
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#include "xfs_trans_priv.h"
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#include "xfs_inode_item.h"
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#include "xfs_bmap.h"
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#include "xfs_btree_trace.h"
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#include "xfs_trace.h"
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/*
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* Allocate and initialise an xfs_inode.
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*/
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STATIC struct xfs_inode *
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xfs_inode_alloc(
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struct xfs_mount *mp,
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xfs_ino_t ino)
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{
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struct xfs_inode *ip;
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/*
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* if this didn't occur in transactions, we could use
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* KM_MAYFAIL and return NULL here on ENOMEM. Set the
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* code up to do this anyway.
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*/
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ip = kmem_zone_alloc(xfs_inode_zone, KM_SLEEP);
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if (!ip)
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return NULL;
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if (inode_init_always(mp->m_super, VFS_I(ip))) {
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kmem_zone_free(xfs_inode_zone, ip);
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return NULL;
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}
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ASSERT(atomic_read(&ip->i_iocount) == 0);
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ASSERT(atomic_read(&ip->i_pincount) == 0);
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ASSERT(!spin_is_locked(&ip->i_flags_lock));
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ASSERT(completion_done(&ip->i_flush));
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mrlock_init(&ip->i_iolock, MRLOCK_BARRIER, "xfsio", ip->i_ino);
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/* initialise the xfs inode */
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ip->i_ino = ino;
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ip->i_mount = mp;
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memset(&ip->i_imap, 0, sizeof(struct xfs_imap));
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ip->i_afp = NULL;
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memset(&ip->i_df, 0, sizeof(xfs_ifork_t));
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ip->i_flags = 0;
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ip->i_update_core = 0;
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ip->i_delayed_blks = 0;
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memset(&ip->i_d, 0, sizeof(xfs_icdinode_t));
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ip->i_size = 0;
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ip->i_new_size = 0;
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/* prevent anyone from using this yet */
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VFS_I(ip)->i_state = I_NEW;
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return ip;
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}
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STATIC void
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xfs_inode_free_callback(
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struct rcu_head *head)
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{
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struct inode *inode = container_of(head, struct inode, i_rcu);
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struct xfs_inode *ip = XFS_I(inode);
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INIT_LIST_HEAD(&inode->i_dentry);
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kmem_zone_free(xfs_inode_zone, ip);
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}
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void
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xfs_inode_free(
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struct xfs_inode *ip)
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{
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switch (ip->i_d.di_mode & S_IFMT) {
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case S_IFREG:
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case S_IFDIR:
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case S_IFLNK:
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xfs_idestroy_fork(ip, XFS_DATA_FORK);
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break;
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}
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if (ip->i_afp)
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xfs_idestroy_fork(ip, XFS_ATTR_FORK);
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if (ip->i_itemp) {
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/*
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* Only if we are shutting down the fs will we see an
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* inode still in the AIL. If it is there, we should remove
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* it to prevent a use-after-free from occurring.
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*/
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xfs_log_item_t *lip = &ip->i_itemp->ili_item;
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struct xfs_ail *ailp = lip->li_ailp;
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ASSERT(((lip->li_flags & XFS_LI_IN_AIL) == 0) ||
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XFS_FORCED_SHUTDOWN(ip->i_mount));
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if (lip->li_flags & XFS_LI_IN_AIL) {
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spin_lock(&ailp->xa_lock);
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if (lip->li_flags & XFS_LI_IN_AIL)
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xfs_trans_ail_delete(ailp, lip);
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else
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spin_unlock(&ailp->xa_lock);
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}
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xfs_inode_item_destroy(ip);
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ip->i_itemp = NULL;
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}
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/* asserts to verify all state is correct here */
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ASSERT(atomic_read(&ip->i_iocount) == 0);
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ASSERT(atomic_read(&ip->i_pincount) == 0);
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ASSERT(!spin_is_locked(&ip->i_flags_lock));
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ASSERT(completion_done(&ip->i_flush));
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call_rcu(&ip->i_vnode.i_rcu, xfs_inode_free_callback);
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}
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/*
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* Check the validity of the inode we just found it the cache
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*/
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static int
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xfs_iget_cache_hit(
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struct xfs_perag *pag,
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struct xfs_inode *ip,
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int flags,
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int lock_flags) __releases(pag->pag_ici_lock)
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{
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struct inode *inode = VFS_I(ip);
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struct xfs_mount *mp = ip->i_mount;
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int error;
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spin_lock(&ip->i_flags_lock);
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/*
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* If we are racing with another cache hit that is currently
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* instantiating this inode or currently recycling it out of
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* reclaimabe state, wait for the initialisation to complete
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* before continuing.
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*
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* XXX(hch): eventually we should do something equivalent to
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* wait_on_inode to wait for these flags to be cleared
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* instead of polling for it.
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*/
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if (ip->i_flags & (XFS_INEW|XFS_IRECLAIM)) {
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trace_xfs_iget_skip(ip);
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XFS_STATS_INC(xs_ig_frecycle);
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error = EAGAIN;
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goto out_error;
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}
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/*
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* If lookup is racing with unlink return an error immediately.
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*/
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if (ip->i_d.di_mode == 0 && !(flags & XFS_IGET_CREATE)) {
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error = ENOENT;
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goto out_error;
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}
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/*
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* If IRECLAIMABLE is set, we've torn down the VFS inode already.
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* Need to carefully get it back into useable state.
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*/
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if (ip->i_flags & XFS_IRECLAIMABLE) {
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trace_xfs_iget_reclaim(ip);
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/*
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* We need to set XFS_IRECLAIM to prevent xfs_reclaim_inode
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* from stomping over us while we recycle the inode. We can't
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* clear the radix tree reclaimable tag yet as it requires
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* pag_ici_lock to be held exclusive.
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*/
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ip->i_flags |= XFS_IRECLAIM;
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spin_unlock(&ip->i_flags_lock);
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read_unlock(&pag->pag_ici_lock);
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error = -inode_init_always(mp->m_super, inode);
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if (error) {
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/*
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* Re-initializing the inode failed, and we are in deep
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* trouble. Try to re-add it to the reclaim list.
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*/
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read_lock(&pag->pag_ici_lock);
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spin_lock(&ip->i_flags_lock);
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ip->i_flags &= ~XFS_INEW;
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ip->i_flags |= XFS_IRECLAIMABLE;
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__xfs_inode_set_reclaim_tag(pag, ip);
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trace_xfs_iget_reclaim_fail(ip);
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goto out_error;
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}
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write_lock(&pag->pag_ici_lock);
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spin_lock(&ip->i_flags_lock);
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ip->i_flags &= ~(XFS_IRECLAIMABLE | XFS_IRECLAIM);
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ip->i_flags |= XFS_INEW;
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__xfs_inode_clear_reclaim_tag(mp, pag, ip);
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inode->i_state = I_NEW;
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spin_unlock(&ip->i_flags_lock);
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write_unlock(&pag->pag_ici_lock);
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} else {
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/* If the VFS inode is being torn down, pause and try again. */
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if (!igrab(inode)) {
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trace_xfs_iget_skip(ip);
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error = EAGAIN;
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goto out_error;
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}
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/* We've got a live one. */
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spin_unlock(&ip->i_flags_lock);
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read_unlock(&pag->pag_ici_lock);
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trace_xfs_iget_hit(ip);
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}
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if (lock_flags != 0)
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xfs_ilock(ip, lock_flags);
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xfs_iflags_clear(ip, XFS_ISTALE);
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XFS_STATS_INC(xs_ig_found);
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return 0;
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out_error:
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spin_unlock(&ip->i_flags_lock);
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read_unlock(&pag->pag_ici_lock);
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return error;
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}
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static int
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xfs_iget_cache_miss(
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struct xfs_mount *mp,
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struct xfs_perag *pag,
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xfs_trans_t *tp,
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xfs_ino_t ino,
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struct xfs_inode **ipp,
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int flags,
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int lock_flags)
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{
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struct xfs_inode *ip;
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int error;
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xfs_agino_t agino = XFS_INO_TO_AGINO(mp, ino);
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ip = xfs_inode_alloc(mp, ino);
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if (!ip)
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return ENOMEM;
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error = xfs_iread(mp, tp, ip, flags);
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if (error)
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goto out_destroy;
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trace_xfs_iget_miss(ip);
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if ((ip->i_d.di_mode == 0) && !(flags & XFS_IGET_CREATE)) {
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error = ENOENT;
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goto out_destroy;
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}
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/*
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* Preload the radix tree so we can insert safely under the
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* write spinlock. Note that we cannot sleep inside the preload
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* region.
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*/
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if (radix_tree_preload(GFP_KERNEL)) {
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error = EAGAIN;
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goto out_destroy;
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}
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/*
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* Because the inode hasn't been added to the radix-tree yet it can't
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* be found by another thread, so we can do the non-sleeping lock here.
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*/
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if (lock_flags) {
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if (!xfs_ilock_nowait(ip, lock_flags))
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BUG();
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}
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write_lock(&pag->pag_ici_lock);
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/* insert the new inode */
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error = radix_tree_insert(&pag->pag_ici_root, agino, ip);
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if (unlikely(error)) {
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WARN_ON(error != -EEXIST);
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XFS_STATS_INC(xs_ig_dup);
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error = EAGAIN;
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goto out_preload_end;
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}
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/* These values _must_ be set before releasing the radix tree lock! */
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ip->i_udquot = ip->i_gdquot = NULL;
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xfs_iflags_set(ip, XFS_INEW);
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write_unlock(&pag->pag_ici_lock);
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radix_tree_preload_end();
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*ipp = ip;
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return 0;
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out_preload_end:
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write_unlock(&pag->pag_ici_lock);
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radix_tree_preload_end();
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if (lock_flags)
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xfs_iunlock(ip, lock_flags);
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out_destroy:
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__destroy_inode(VFS_I(ip));
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xfs_inode_free(ip);
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return error;
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}
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/*
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* Look up an inode by number in the given file system.
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* The inode is looked up in the cache held in each AG.
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* If the inode is found in the cache, initialise the vfs inode
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* if necessary.
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*
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* If it is not in core, read it in from the file system's device,
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* add it to the cache and initialise the vfs inode.
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*
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* The inode is locked according to the value of the lock_flags parameter.
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* This flag parameter indicates how and if the inode's IO lock and inode lock
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* should be taken.
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*
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* mp -- the mount point structure for the current file system. It points
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* to the inode hash table.
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* tp -- a pointer to the current transaction if there is one. This is
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* simply passed through to the xfs_iread() call.
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* ino -- the number of the inode desired. This is the unique identifier
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* within the file system for the inode being requested.
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* lock_flags -- flags indicating how to lock the inode. See the comment
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* for xfs_ilock() for a list of valid values.
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*/
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int
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xfs_iget(
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xfs_mount_t *mp,
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xfs_trans_t *tp,
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xfs_ino_t ino,
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uint flags,
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uint lock_flags,
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xfs_inode_t **ipp)
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{
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xfs_inode_t *ip;
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int error;
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xfs_perag_t *pag;
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xfs_agino_t agino;
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/* reject inode numbers outside existing AGs */
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if (XFS_INO_TO_AGNO(mp, ino) >= mp->m_sb.sb_agcount)
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return EINVAL;
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/* get the perag structure and ensure that it's inode capable */
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pag = xfs_perag_get(mp, XFS_INO_TO_AGNO(mp, ino));
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agino = XFS_INO_TO_AGINO(mp, ino);
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again:
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error = 0;
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read_lock(&pag->pag_ici_lock);
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ip = radix_tree_lookup(&pag->pag_ici_root, agino);
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if (ip) {
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error = xfs_iget_cache_hit(pag, ip, flags, lock_flags);
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if (error)
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goto out_error_or_again;
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} else {
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read_unlock(&pag->pag_ici_lock);
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XFS_STATS_INC(xs_ig_missed);
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error = xfs_iget_cache_miss(mp, pag, tp, ino, &ip,
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flags, lock_flags);
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if (error)
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goto out_error_or_again;
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}
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xfs_perag_put(pag);
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*ipp = ip;
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ASSERT(ip->i_df.if_ext_max ==
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XFS_IFORK_DSIZE(ip) / sizeof(xfs_bmbt_rec_t));
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/*
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* If we have a real type for an on-disk inode, we can set ops(&unlock)
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* now. If it's a new inode being created, xfs_ialloc will handle it.
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*/
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if (xfs_iflags_test(ip, XFS_INEW) && ip->i_d.di_mode != 0)
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xfs_setup_inode(ip);
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return 0;
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out_error_or_again:
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if (error == EAGAIN) {
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delay(1);
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goto again;
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}
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xfs_perag_put(pag);
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return error;
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}
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/*
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* This is a wrapper routine around the xfs_ilock() routine
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* used to centralize some grungy code. It is used in places
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* that wish to lock the inode solely for reading the extents.
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* The reason these places can't just call xfs_ilock(SHARED)
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* is that the inode lock also guards to bringing in of the
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* extents from disk for a file in b-tree format. If the inode
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* is in b-tree format, then we need to lock the inode exclusively
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* until the extents are read in. Locking it exclusively all
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* the time would limit our parallelism unnecessarily, though.
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* What we do instead is check to see if the extents have been
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* read in yet, and only lock the inode exclusively if they
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* have not.
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*
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* The function returns a value which should be given to the
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* corresponding xfs_iunlock_map_shared(). This value is
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* the mode in which the lock was actually taken.
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*/
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uint
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xfs_ilock_map_shared(
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xfs_inode_t *ip)
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{
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uint lock_mode;
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if ((ip->i_d.di_format == XFS_DINODE_FMT_BTREE) &&
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((ip->i_df.if_flags & XFS_IFEXTENTS) == 0)) {
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lock_mode = XFS_ILOCK_EXCL;
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} else {
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lock_mode = XFS_ILOCK_SHARED;
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}
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xfs_ilock(ip, lock_mode);
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return lock_mode;
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}
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/*
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* This is simply the unlock routine to go with xfs_ilock_map_shared().
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* All it does is call xfs_iunlock() with the given lock_mode.
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*/
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void
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xfs_iunlock_map_shared(
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xfs_inode_t *ip,
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unsigned int lock_mode)
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{
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xfs_iunlock(ip, lock_mode);
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}
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/*
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* The xfs inode contains 2 locks: a multi-reader lock called the
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* i_iolock and a multi-reader lock called the i_lock. This routine
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* allows either or both of the locks to be obtained.
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*
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* The 2 locks should always be ordered so that the IO lock is
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* obtained first in order to prevent deadlock.
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|
*
|
|
* ip -- the inode being locked
|
|
* lock_flags -- this parameter indicates the inode's locks
|
|
* to be locked. It can be:
|
|
* XFS_IOLOCK_SHARED,
|
|
* XFS_IOLOCK_EXCL,
|
|
* XFS_ILOCK_SHARED,
|
|
* XFS_ILOCK_EXCL,
|
|
* XFS_IOLOCK_SHARED | XFS_ILOCK_SHARED,
|
|
* XFS_IOLOCK_SHARED | XFS_ILOCK_EXCL,
|
|
* XFS_IOLOCK_EXCL | XFS_ILOCK_SHARED,
|
|
* XFS_IOLOCK_EXCL | XFS_ILOCK_EXCL
|
|
*/
|
|
void
|
|
xfs_ilock(
|
|
xfs_inode_t *ip,
|
|
uint lock_flags)
|
|
{
|
|
/*
|
|
* You can't set both SHARED and EXCL for the same lock,
|
|
* and only XFS_IOLOCK_SHARED, XFS_IOLOCK_EXCL, XFS_ILOCK_SHARED,
|
|
* and XFS_ILOCK_EXCL are valid values to set in lock_flags.
|
|
*/
|
|
ASSERT((lock_flags & (XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL)) !=
|
|
(XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL));
|
|
ASSERT((lock_flags & (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL)) !=
|
|
(XFS_ILOCK_SHARED | XFS_ILOCK_EXCL));
|
|
ASSERT((lock_flags & ~(XFS_LOCK_MASK | XFS_LOCK_DEP_MASK)) == 0);
|
|
|
|
if (lock_flags & XFS_IOLOCK_EXCL)
|
|
mrupdate_nested(&ip->i_iolock, XFS_IOLOCK_DEP(lock_flags));
|
|
else if (lock_flags & XFS_IOLOCK_SHARED)
|
|
mraccess_nested(&ip->i_iolock, XFS_IOLOCK_DEP(lock_flags));
|
|
|
|
if (lock_flags & XFS_ILOCK_EXCL)
|
|
mrupdate_nested(&ip->i_lock, XFS_ILOCK_DEP(lock_flags));
|
|
else if (lock_flags & XFS_ILOCK_SHARED)
|
|
mraccess_nested(&ip->i_lock, XFS_ILOCK_DEP(lock_flags));
|
|
|
|
trace_xfs_ilock(ip, lock_flags, _RET_IP_);
|
|
}
|
|
|
|
/*
|
|
* This is just like xfs_ilock(), except that the caller
|
|
* is guaranteed not to sleep. It returns 1 if it gets
|
|
* the requested locks and 0 otherwise. If the IO lock is
|
|
* obtained but the inode lock cannot be, then the IO lock
|
|
* is dropped before returning.
|
|
*
|
|
* ip -- the inode being locked
|
|
* lock_flags -- this parameter indicates the inode's locks to be
|
|
* to be locked. See the comment for xfs_ilock() for a list
|
|
* of valid values.
|
|
*/
|
|
int
|
|
xfs_ilock_nowait(
|
|
xfs_inode_t *ip,
|
|
uint lock_flags)
|
|
{
|
|
/*
|
|
* You can't set both SHARED and EXCL for the same lock,
|
|
* and only XFS_IOLOCK_SHARED, XFS_IOLOCK_EXCL, XFS_ILOCK_SHARED,
|
|
* and XFS_ILOCK_EXCL are valid values to set in lock_flags.
|
|
*/
|
|
ASSERT((lock_flags & (XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL)) !=
|
|
(XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL));
|
|
ASSERT((lock_flags & (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL)) !=
|
|
(XFS_ILOCK_SHARED | XFS_ILOCK_EXCL));
|
|
ASSERT((lock_flags & ~(XFS_LOCK_MASK | XFS_LOCK_DEP_MASK)) == 0);
|
|
|
|
if (lock_flags & XFS_IOLOCK_EXCL) {
|
|
if (!mrtryupdate(&ip->i_iolock))
|
|
goto out;
|
|
} else if (lock_flags & XFS_IOLOCK_SHARED) {
|
|
if (!mrtryaccess(&ip->i_iolock))
|
|
goto out;
|
|
}
|
|
if (lock_flags & XFS_ILOCK_EXCL) {
|
|
if (!mrtryupdate(&ip->i_lock))
|
|
goto out_undo_iolock;
|
|
} else if (lock_flags & XFS_ILOCK_SHARED) {
|
|
if (!mrtryaccess(&ip->i_lock))
|
|
goto out_undo_iolock;
|
|
}
|
|
trace_xfs_ilock_nowait(ip, lock_flags, _RET_IP_);
|
|
return 1;
|
|
|
|
out_undo_iolock:
|
|
if (lock_flags & XFS_IOLOCK_EXCL)
|
|
mrunlock_excl(&ip->i_iolock);
|
|
else if (lock_flags & XFS_IOLOCK_SHARED)
|
|
mrunlock_shared(&ip->i_iolock);
|
|
out:
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* xfs_iunlock() is used to drop the inode locks acquired with
|
|
* xfs_ilock() and xfs_ilock_nowait(). The caller must pass
|
|
* in the flags given to xfs_ilock() or xfs_ilock_nowait() so
|
|
* that we know which locks to drop.
|
|
*
|
|
* ip -- the inode being unlocked
|
|
* lock_flags -- this parameter indicates the inode's locks to be
|
|
* to be unlocked. See the comment for xfs_ilock() for a list
|
|
* of valid values for this parameter.
|
|
*
|
|
*/
|
|
void
|
|
xfs_iunlock(
|
|
xfs_inode_t *ip,
|
|
uint lock_flags)
|
|
{
|
|
/*
|
|
* You can't set both SHARED and EXCL for the same lock,
|
|
* and only XFS_IOLOCK_SHARED, XFS_IOLOCK_EXCL, XFS_ILOCK_SHARED,
|
|
* and XFS_ILOCK_EXCL are valid values to set in lock_flags.
|
|
*/
|
|
ASSERT((lock_flags & (XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL)) !=
|
|
(XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL));
|
|
ASSERT((lock_flags & (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL)) !=
|
|
(XFS_ILOCK_SHARED | XFS_ILOCK_EXCL));
|
|
ASSERT((lock_flags & ~(XFS_LOCK_MASK | XFS_IUNLOCK_NONOTIFY |
|
|
XFS_LOCK_DEP_MASK)) == 0);
|
|
ASSERT(lock_flags != 0);
|
|
|
|
if (lock_flags & XFS_IOLOCK_EXCL)
|
|
mrunlock_excl(&ip->i_iolock);
|
|
else if (lock_flags & XFS_IOLOCK_SHARED)
|
|
mrunlock_shared(&ip->i_iolock);
|
|
|
|
if (lock_flags & XFS_ILOCK_EXCL)
|
|
mrunlock_excl(&ip->i_lock);
|
|
else if (lock_flags & XFS_ILOCK_SHARED)
|
|
mrunlock_shared(&ip->i_lock);
|
|
|
|
if ((lock_flags & (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL)) &&
|
|
!(lock_flags & XFS_IUNLOCK_NONOTIFY) && ip->i_itemp) {
|
|
/*
|
|
* Let the AIL know that this item has been unlocked in case
|
|
* it is in the AIL and anyone is waiting on it. Don't do
|
|
* this if the caller has asked us not to.
|
|
*/
|
|
xfs_trans_unlocked_item(ip->i_itemp->ili_item.li_ailp,
|
|
(xfs_log_item_t*)(ip->i_itemp));
|
|
}
|
|
trace_xfs_iunlock(ip, lock_flags, _RET_IP_);
|
|
}
|
|
|
|
/*
|
|
* give up write locks. the i/o lock cannot be held nested
|
|
* if it is being demoted.
|
|
*/
|
|
void
|
|
xfs_ilock_demote(
|
|
xfs_inode_t *ip,
|
|
uint lock_flags)
|
|
{
|
|
ASSERT(lock_flags & (XFS_IOLOCK_EXCL|XFS_ILOCK_EXCL));
|
|
ASSERT((lock_flags & ~(XFS_IOLOCK_EXCL|XFS_ILOCK_EXCL)) == 0);
|
|
|
|
if (lock_flags & XFS_ILOCK_EXCL)
|
|
mrdemote(&ip->i_lock);
|
|
if (lock_flags & XFS_IOLOCK_EXCL)
|
|
mrdemote(&ip->i_iolock);
|
|
|
|
trace_xfs_ilock_demote(ip, lock_flags, _RET_IP_);
|
|
}
|
|
|
|
#ifdef DEBUG
|
|
int
|
|
xfs_isilocked(
|
|
xfs_inode_t *ip,
|
|
uint lock_flags)
|
|
{
|
|
if (lock_flags & (XFS_ILOCK_EXCL|XFS_ILOCK_SHARED)) {
|
|
if (!(lock_flags & XFS_ILOCK_SHARED))
|
|
return !!ip->i_lock.mr_writer;
|
|
return rwsem_is_locked(&ip->i_lock.mr_lock);
|
|
}
|
|
|
|
if (lock_flags & (XFS_IOLOCK_EXCL|XFS_IOLOCK_SHARED)) {
|
|
if (!(lock_flags & XFS_IOLOCK_SHARED))
|
|
return !!ip->i_iolock.mr_writer;
|
|
return rwsem_is_locked(&ip->i_iolock.mr_lock);
|
|
}
|
|
|
|
ASSERT(0);
|
|
return 0;
|
|
}
|
|
#endif
|