[XFS] shrink mrlock_t

The writer field is not needed for non_DEBU builds so remove it. While
we're at i also clean up the interface for is locked asserts to go through
and xfs_iget.c helper with an interface like the xfs_ilock routines to
isolated the XFS codebase from mrlock internals. That way we can kill
mrlock_t entirely once rw_semaphores grow an islocked facility. Also
remove unused flags to the ilock family of functions.

SGI-PV: 976035
SGI-Modid: xfs-linux-melb:xfs-kern:30902a

Signed-off-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>

15 files changed, 154 insertions, 175 deletions

diff --git a/fs/xfs/linux-2.6/mrlock.h b/fs/xfs/linux-2.6/mrlock.h
index c110bb002665..ff6a19873e5c 100644
--- a/fs/xfs/linux-2.6/mrlock.h
+++ b/fs/xfs/linux-2.6/mrlock.h
@@ -20,29 +20,24 @@
 
 #include <linux/rwsem.h>
 
-enum { MR_NONE, MR_ACCESS, MR_UPDATE };
-
 typedef struct {
         struct rw_semaphore     mr_lock;
+#ifdef DEBUG
         int                     mr_writer;
+#endif
 } mrlock_t;
 
+#ifdef DEBUG
 #define mrinit(mrp, name)       \
         do { (mrp)->mr_writer = 0; init_rwsem(&(mrp)->mr_lock); } while (0)
+#else
+#define mrinit(mrp, name)       \
+        do { init_rwsem(&(mrp)->mr_lock); } while (0)
+#endif
+
 #define mrlock_init(mrp, t,n,s) mrinit(mrp, n)
 #define mrfree(mrp)             do { } while (0)
 
-static inline void mraccess(mrlock_t *mrp)
-{
-        down_read(&mrp->mr_lock);
-}
-
-static inline void mrupdate(mrlock_t *mrp)
-{
-        down_write(&mrp->mr_lock);
-        mrp->mr_writer = 1;
-}
-
 static inline void mraccess_nested(mrlock_t *mrp, int subclass)
 {
         down_read_nested(&mrp->mr_lock, subclass);
@@ -51,10 +46,11 @@ static inline void mraccess_nested(mrlock_t *mrp, int subclass)
 static inline void mrupdate_nested(mrlock_t *mrp, int subclass)
 {
         down_write_nested(&mrp->mr_lock, subclass);
+#ifdef DEBUG
         mrp->mr_writer = 1;
+#endif
 }
 
-
 static inline int mrtryaccess(mrlock_t *mrp)
 {
         return down_read_trylock(&mrp->mr_lock);
@@ -64,39 +60,31 @@ static inline int mrtryupdate(mrlock_t *mrp)
 {
         if (!down_write_trylock(&mrp->mr_lock))
                 return 0;
+#ifdef DEBUG
         mrp->mr_writer = 1;
+#endif
         return 1;
 }
 
-static inline void mrunlock(mrlock_t *mrp)
+static inline void mrunlock_excl(mrlock_t *mrp)
 {
-        if (mrp->mr_writer) {
-                mrp->mr_writer = 0;
-                up_write(&mrp->mr_lock);
-        } else {
-                up_read(&mrp->mr_lock);
-        }
+#ifdef DEBUG
+        mrp->mr_writer = 0;
+#endif
+        up_write(&mrp->mr_lock);
 }
 
-static inline void mrdemote(mrlock_t *mrp)
+static inline void mrunlock_shared(mrlock_t *mrp)
 {
-        mrp->mr_writer = 0;
-        downgrade_write(&mrp->mr_lock);
+        up_read(&mrp->mr_lock);
 }
 
-#ifdef DEBUG
-/*
- * Debug-only routine, without some platform-specific asm code, we can
- * now only answer requests regarding whether we hold the lock for write
- * (reader state is outside our visibility, we only track writer state).
- * Note: means !ismrlocked would give false positives, so don't do that.
- */
-static inline int ismrlocked(mrlock_t *mrp, int type)
+static inline void mrdemote(mrlock_t *mrp)
 {
-        if (mrp && type == MR_UPDATE)
-                return mrp->mr_writer;
-        return 1;
-}
+#ifdef DEBUG
+        mrp->mr_writer = 0;
 #endif
+        downgrade_write(&mrp->mr_lock);
+}
 
 #endif /* __XFS_SUPPORT_MRLOCK_H__ */
diff --git a/fs/xfs/linux-2.6/xfs_lrw.c b/fs/xfs/linux-2.6/xfs_lrw.c
index 1ebd8004469c..5e3b57516ec7 100644
--- a/fs/xfs/linux-2.6/xfs_lrw.c
+++ b/fs/xfs/linux-2.6/xfs_lrw.c
@@ -394,7 +394,7 @@ xfs_zero_last_block(
         int             error = 0;
         xfs_bmbt_irec_t imap;
 
-        ASSERT(ismrlocked(&ip->i_lock, MR_UPDATE) != 0);
+        ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
 
         zero_offset = XFS_B_FSB_OFFSET(mp, isize);
         if (zero_offset == 0) {
@@ -425,14 +425,14 @@ xfs_zero_last_block(
          * out sync.  We need to drop the ilock while we do this so we
          * don't deadlock when the buffer cache calls back to us.
          */
-        xfs_iunlock(ip, XFS_ILOCK_EXCL| XFS_EXTSIZE_RD);
+        xfs_iunlock(ip, XFS_ILOCK_EXCL);
 
         zero_len = mp->m_sb.sb_blocksize - zero_offset;
         if (isize + zero_len > offset)
                 zero_len = offset - isize;
         error = xfs_iozero(ip, isize, zero_len);
 
-        xfs_ilock(ip, XFS_ILOCK_EXCL|XFS_EXTSIZE_RD);
+        xfs_ilock(ip, XFS_ILOCK_EXCL);
         ASSERT(error >= 0);
         return error;
 }
@@ -465,8 +465,7 @@ xfs_zero_eof(
         int             error = 0;
         xfs_bmbt_irec_t imap;
 
-        ASSERT(ismrlocked(&ip->i_lock, MR_UPDATE));
-        ASSERT(ismrlocked(&ip->i_iolock, MR_UPDATE));
+        ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL|XFS_IOLOCK_EXCL));
         ASSERT(offset > isize);
 
         /*
@@ -475,8 +474,7 @@ xfs_zero_eof(
          */
         error = xfs_zero_last_block(ip, offset, isize);
         if (error) {
-                ASSERT(ismrlocked(&ip->i_lock, MR_UPDATE));
-                ASSERT(ismrlocked(&ip->i_iolock, MR_UPDATE));
+                ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL|XFS_IOLOCK_EXCL));
                 return error;
         }
 
@@ -507,8 +505,7 @@ xfs_zero_eof(
                 error = xfs_bmapi(NULL, ip, start_zero_fsb, zero_count_fsb,
                                   0, NULL, 0, &imap, &nimaps, NULL, NULL);
                 if (error) {
-                        ASSERT(ismrlocked(&ip->i_lock, MR_UPDATE));
-                        ASSERT(ismrlocked(&ip->i_iolock, MR_UPDATE));
+                        ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL|XFS_IOLOCK_EXCL));
                         return error;
                 }
                 ASSERT(nimaps > 0);
@@ -532,7 +529,7 @@ xfs_zero_eof(
                  * Drop the inode lock while we're doing the I/O.
                  * We'll still have the iolock to protect us.
                  */
-                xfs_iunlock(ip, XFS_ILOCK_EXCL|XFS_EXTSIZE_RD);
+                xfs_iunlock(ip, XFS_ILOCK_EXCL);
 
                 zero_off = XFS_FSB_TO_B(mp, start_zero_fsb);
                 zero_len = XFS_FSB_TO_B(mp, imap.br_blockcount);
@@ -548,13 +545,13 @@ xfs_zero_eof(
                 start_zero_fsb = imap.br_startoff + imap.br_blockcount;
                 ASSERT(start_zero_fsb <= (end_zero_fsb + 1));
 
-                xfs_ilock(ip, XFS_ILOCK_EXCL|XFS_EXTSIZE_RD);
+                xfs_ilock(ip, XFS_ILOCK_EXCL);
         }
 
         return 0;
 
 out_lock:
-        xfs_ilock(ip, XFS_ILOCK_EXCL|XFS_EXTSIZE_RD);
+        xfs_ilock(ip, XFS_ILOCK_EXCL);
         ASSERT(error >= 0);
         return error;
 }
diff --git a/fs/xfs/quota/xfs_dquot.c b/fs/xfs/quota/xfs_dquot.c
index 631ebb31b295..85df3288efd5 100644
--- a/fs/xfs/quota/xfs_dquot.c
+++ b/fs/xfs/quota/xfs_dquot.c
@@ -933,7 +933,7 @@ xfs_qm_dqget(
                type == XFS_DQ_PROJ ||
                type == XFS_DQ_GROUP);
         if (ip) {
-                ASSERT(XFS_ISLOCKED_INODE_EXCL(ip));
+                ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
                 if (type == XFS_DQ_USER)
                         ASSERT(ip->i_udquot == NULL);
                 else
@@ -1088,7 +1088,7 @@ xfs_qm_dqget(
         xfs_qm_mplist_unlock(mp);
         XFS_DQ_HASH_UNLOCK(h);
  dqret:
-        ASSERT((ip == NULL) || XFS_ISLOCKED_INODE_EXCL(ip));
+        ASSERT((ip == NULL) || xfs_isilocked(ip, XFS_ILOCK_EXCL));
         xfs_dqtrace_entry(dqp, "DQGET DONE");
         *O_dqpp = dqp;
         return (0);
diff --git a/fs/xfs/quota/xfs_qm.c b/fs/xfs/quota/xfs_qm.c
index fb624a17f15b..d31cce1165c5 100644
--- a/fs/xfs/quota/xfs_qm.c
+++ b/fs/xfs/quota/xfs_qm.c
@@ -670,7 +670,7 @@ xfs_qm_dqattach_one(
         xfs_dquot_t     *dqp;
         int             error;
 
-        ASSERT(XFS_ISLOCKED_INODE_EXCL(ip));
+        ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
         error = 0;
         /*
          * See if we already have it in the inode itself. IO_idqpp is
@@ -874,7 +874,7 @@ xfs_qm_dqattach(
                 return 0;
 
         ASSERT((flags & XFS_QMOPT_ILOCKED) == 0 ||
-               XFS_ISLOCKED_INODE_EXCL(ip));
+               xfs_isilocked(ip, XFS_ILOCK_EXCL));
 
         if (! (flags & XFS_QMOPT_ILOCKED))
                 xfs_ilock(ip, XFS_ILOCK_EXCL);
@@ -888,7 +888,8 @@ xfs_qm_dqattach(
                         goto done;
                 nquotas++;
         }
-        ASSERT(XFS_ISLOCKED_INODE_EXCL(ip));
+
+        ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
         if (XFS_IS_OQUOTA_ON(mp)) {
                 error = XFS_IS_GQUOTA_ON(mp) ?
                         xfs_qm_dqattach_one(ip, ip->i_d.di_gid, XFS_DQ_GROUP,
@@ -913,7 +914,7 @@ xfs_qm_dqattach(
          * This WON'T, in general, result in a thrash.
          */
         if (nquotas == 2) {
-                ASSERT(XFS_ISLOCKED_INODE_EXCL(ip));
+                ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
                 ASSERT(ip->i_udquot);
                 ASSERT(ip->i_gdquot);
 
@@ -956,7 +957,7 @@ xfs_qm_dqattach(
 
 #ifdef QUOTADEBUG
         else
-                ASSERT(XFS_ISLOCKED_INODE_EXCL(ip));
+                ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
 #endif
         return error;
 }
@@ -1291,7 +1292,7 @@ xfs_qm_dqget_noattach(
         xfs_mount_t     *mp;
         xfs_dquot_t     *udqp, *gdqp;
 
-        ASSERT(XFS_ISLOCKED_INODE_EXCL(ip));
+        ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
         mp = ip->i_mount;
         udqp = NULL;
         gdqp = NULL;
@@ -1392,7 +1393,7 @@ xfs_qm_qino_alloc(
          * Keep an extra reference to this quota inode. This inode is
          * locked exclusively and joined to the transaction already.
          */
-        ASSERT(XFS_ISLOCKED_INODE_EXCL(*ip));
+        ASSERT(xfs_isilocked(*ip, XFS_ILOCK_EXCL));
         VN_HOLD(XFS_ITOV((*ip)));
 
         /*
@@ -2557,7 +2558,7 @@ xfs_qm_vop_chown(
         uint            bfield = XFS_IS_REALTIME_INODE(ip) ?
                                  XFS_TRANS_DQ_RTBCOUNT : XFS_TRANS_DQ_BCOUNT;
 
-        ASSERT(XFS_ISLOCKED_INODE_EXCL(ip));
+        ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
         ASSERT(XFS_IS_QUOTA_RUNNING(ip->i_mount));
 
         /* old dquot */
@@ -2601,7 +2602,7 @@ xfs_qm_vop_chown_reserve(
         uint            delblks, blkflags, prjflags = 0;
         xfs_dquot_t     *unresudq, *unresgdq, *delblksudq, *delblksgdq;
 
-        ASSERT(XFS_ISLOCKED_INODE(ip));
+        ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL|XFS_ILOCK_SHARED));
         mp = ip->i_mount;
         ASSERT(XFS_IS_QUOTA_RUNNING(mp));
 
@@ -2711,7 +2712,7 @@ xfs_qm_vop_dqattach_and_dqmod_newinode(
         if (!XFS_IS_QUOTA_ON(tp->t_mountp))
                 return;
 
-        ASSERT(XFS_ISLOCKED_INODE_EXCL(ip));
+        ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
         ASSERT(XFS_IS_QUOTA_RUNNING(tp->t_mountp));
 
         if (udqp) {
diff --git a/fs/xfs/quota/xfs_quota_priv.h b/fs/xfs/quota/xfs_quota_priv.h
index a8b85e2be9d5..5e4a40b1c565 100644
--- a/fs/xfs/quota/xfs_quota_priv.h
+++ b/fs/xfs/quota/xfs_quota_priv.h
@@ -27,11 +27,6 @@
 /* Number of dquots that fit in to a dquot block */
 #define XFS_QM_DQPERBLK(mp)     ((mp)->m_quotainfo->qi_dqperchunk)
 
-#define XFS_ISLOCKED_INODE(ip)          (ismrlocked(&(ip)->i_lock, \
-                                            MR_UPDATE | MR_ACCESS) != 0)
-#define XFS_ISLOCKED_INODE_EXCL(ip)     (ismrlocked(&(ip)->i_lock, \
-                                            MR_UPDATE) != 0)
-
 #define XFS_DQ_IS_ADDEDTO_TRX(t, d)     ((d)->q_transp == (t))
 
 #define XFS_QI_MPLRECLAIMS(mp)  ((mp)->m_quotainfo->qi_dqreclaims)
diff --git a/fs/xfs/quota/xfs_trans_dquot.c b/fs/xfs/quota/xfs_trans_dquot.c
index f441f836ca8b..99611381e740 100644
--- a/fs/xfs/quota/xfs_trans_dquot.c
+++ b/fs/xfs/quota/xfs_trans_dquot.c
@@ -834,7 +834,7 @@ xfs_trans_reserve_quota_nblks(
         ASSERT(ip->i_ino != mp->m_sb.sb_uquotino);
         ASSERT(ip->i_ino != mp->m_sb.sb_gquotino);
 
-        ASSERT(XFS_ISLOCKED_INODE_EXCL(ip));
+        ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
         ASSERT(XFS_IS_QUOTA_RUNNING(ip->i_mount));
         ASSERT((flags & ~(XFS_QMOPT_FORCE_RES | XFS_QMOPT_ENOSPC)) ==
                                 XFS_TRANS_DQ_RES_RTBLKS ||
diff --git a/fs/xfs/xfs_bmap.c b/fs/xfs/xfs_bmap.c
index eb198c01c35d..53c259f5a5af 100644
--- a/fs/xfs/xfs_bmap.c
+++ b/fs/xfs/xfs_bmap.c
@@ -4074,7 +4074,6 @@ xfs_bmap_add_attrfork(
 error2:
         xfs_bmap_cancel(&flist);
 error1:
-        ASSERT(ismrlocked(&ip->i_lock,MR_UPDATE));
         xfs_iunlock(ip, XFS_ILOCK_EXCL);
 error0:
         xfs_trans_cancel(tp, XFS_TRANS_RELEASE_LOG_RES|XFS_TRANS_ABORT);
diff --git a/fs/xfs/xfs_iget.c b/fs/xfs/xfs_iget.c
index e657c5128460..b07604b94d9f 100644
--- a/fs/xfs/xfs_iget.c
+++ b/fs/xfs/xfs_iget.c
@@ -593,8 +593,9 @@ xfs_iunlock_map_shared(
  *              XFS_IOLOCK_EXCL | XFS_ILOCK_EXCL
  */
 void
-xfs_ilock(xfs_inode_t   *ip,
-          uint          lock_flags)
+xfs_ilock(
+        xfs_inode_t             *ip,
+        uint                    lock_flags)
 {
         /*
          * You can't set both SHARED and EXCL for the same lock,
@@ -607,16 +608,16 @@ xfs_ilock(xfs_inode_t	*ip,
                (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL));
         ASSERT((lock_flags & ~(XFS_LOCK_MASK | XFS_LOCK_DEP_MASK)) == 0);
 
-        if (lock_flags & XFS_IOLOCK_EXCL) {
+        if (lock_flags & XFS_IOLOCK_EXCL)
                 mrupdate_nested(&ip->i_iolock, XFS_IOLOCK_DEP(lock_flags));
-        } else if (lock_flags & XFS_IOLOCK_SHARED) {
+        else if (lock_flags & XFS_IOLOCK_SHARED)
                 mraccess_nested(&ip->i_iolock, XFS_IOLOCK_DEP(lock_flags));
-        }
-        if (lock_flags & XFS_ILOCK_EXCL) {
+
+        if (lock_flags & XFS_ILOCK_EXCL)
                 mrupdate_nested(&ip->i_lock, XFS_ILOCK_DEP(lock_flags));
-        } else if (lock_flags & XFS_ILOCK_SHARED) {
+        else if (lock_flags & XFS_ILOCK_SHARED)
                 mraccess_nested(&ip->i_lock, XFS_ILOCK_DEP(lock_flags));
-        }
+
         xfs_ilock_trace(ip, 1, lock_flags, (inst_t *)__return_address);
 }
 
@@ -631,15 +632,12 @@ xfs_ilock(xfs_inode_t	*ip,
  * 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)
+xfs_ilock_nowait(
+        xfs_inode_t             *ip,
+        uint                    lock_flags)
 {
-        int     iolocked;
-        int     ilocked;
-
         /*
          * You can't set both SHARED and EXCL for the same lock,
          * and only XFS_IOLOCK_SHARED, XFS_IOLOCK_EXCL, XFS_ILOCK_SHARED,
@@ -651,37 +649,30 @@ xfs_ilock_nowait(xfs_inode_t	*ip,
                (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL));
         ASSERT((lock_flags & ~(XFS_LOCK_MASK | XFS_LOCK_DEP_MASK)) == 0);
 
-        iolocked = 0;
         if (lock_flags & XFS_IOLOCK_EXCL) {
-                iolocked = mrtryupdate(&ip->i_iolock);
-                if (!iolocked) {
-                        return 0;
-                }
+                if (!mrtryupdate(&ip->i_iolock))
+                        goto out;
         } else if (lock_flags & XFS_IOLOCK_SHARED) {
-                iolocked = mrtryaccess(&ip->i_iolock);
-                if (!iolocked) {
-                        return 0;
-                }
+                if (!mrtryaccess(&ip->i_iolock))
+                        goto out;
         }
         if (lock_flags & XFS_ILOCK_EXCL) {
-                ilocked = mrtryupdate(&ip->i_lock);
-                if (!ilocked) {
-                        if (iolocked) {
-                                mrunlock(&ip->i_iolock);
-                        }
-                        return 0;
-                }
+                if (!mrtryupdate(&ip->i_lock))
+                        goto out_undo_iolock;
         } else if (lock_flags & XFS_ILOCK_SHARED) {
-                ilocked = mrtryaccess(&ip->i_lock);
-                if (!ilocked) {
-                        if (iolocked) {
-                                mrunlock(&ip->i_iolock);
-                        }
-                        return 0;
-                }
+                if (!mrtryaccess(&ip->i_lock))
+                        goto out_undo_iolock;
         }
         xfs_ilock_trace(ip, 2, lock_flags, (inst_t *)__return_address);
         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;
 }
 
 /*
@@ -697,8 +688,9 @@ xfs_ilock_nowait(xfs_inode_t	*ip,
  *
  */
 void
-xfs_iunlock(xfs_inode_t *ip,
-            uint        lock_flags)
+xfs_iunlock(
+        xfs_inode_t             *ip,
+        uint                    lock_flags)
 {
         /*
          * You can't set both SHARED and EXCL for the same lock,
@@ -713,31 +705,25 @@ xfs_iunlock(xfs_inode_t	*ip,
                         XFS_LOCK_DEP_MASK)) == 0);
         ASSERT(lock_flags != 0);
 
-        if (lock_flags & (XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL)) {
-                ASSERT(!(lock_flags & XFS_IOLOCK_SHARED) ||
-                       (ismrlocked(&ip->i_iolock, MR_ACCESS)));
-                ASSERT(!(lock_flags & XFS_IOLOCK_EXCL) ||
-                       (ismrlocked(&ip->i_iolock, MR_UPDATE)));
-                mrunlock(&ip->i_iolock);
-        }
+        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_SHARED | XFS_ILOCK_EXCL)) {
-                ASSERT(!(lock_flags & XFS_ILOCK_SHARED) ||
-                       (ismrlocked(&ip->i_lock, MR_ACCESS)));
-                ASSERT(!(lock_flags & XFS_ILOCK_EXCL) ||
-                       (ismrlocked(&ip->i_lock, MR_UPDATE)));
-                mrunlock(&ip->i_lock);
+        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.
                  */
-                if (!(lock_flags & XFS_IUNLOCK_NONOTIFY) &&
-                     ip->i_itemp != NULL) {
-                        xfs_trans_unlocked_item(ip->i_mount,
-                                                (xfs_log_item_t*)(ip->i_itemp));
-                }
+                xfs_trans_unlocked_item(ip->i_mount,
+                                        (xfs_log_item_t*)(ip->i_itemp));
         }
         xfs_ilock_trace(ip, 3, lock_flags, (inst_t *)__return_address);
 }
@@ -747,21 +733,47 @@ xfs_iunlock(xfs_inode_t	*ip,
  * if it is being demoted.
  */
 void
-xfs_ilock_demote(xfs_inode_t    *ip,
-                 uint           lock_flags)
+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) {
-                ASSERT(ismrlocked(&ip->i_lock, MR_UPDATE));
+        if (lock_flags & XFS_ILOCK_EXCL)
                 mrdemote(&ip->i_lock);
-        }
-        if (lock_flags & XFS_IOLOCK_EXCL) {
-                ASSERT(ismrlocked(&ip->i_iolock, MR_UPDATE));
+        if (lock_flags & XFS_IOLOCK_EXCL)
                 mrdemote(&ip->i_iolock);
+}
+
+#ifdef DEBUG
+/*
+ * Debug-only routine, without additional rw_semaphore APIs, we can
+ * now only answer requests regarding whether we hold the lock for write
+ * (reader state is outside our visibility, we only track writer state).
+ *
+ * Note: this means !xfs_isilocked would give false positives, so don't do that.
+ */
+int
+xfs_isilocked(
+        xfs_inode_t             *ip,
+        uint                    lock_flags)
+{
+        if ((lock_flags & (XFS_ILOCK_EXCL|XFS_ILOCK_SHARED)) ==
+                        XFS_ILOCK_EXCL) {
+                if (!ip->i_lock.mr_writer)
+                        return 0;
         }
+
+        if ((lock_flags & (XFS_IOLOCK_EXCL|XFS_IOLOCK_SHARED)) ==
+                        XFS_IOLOCK_EXCL) {
+                if (!ip->i_iolock.mr_writer)
+                        return 0;
+        }
+
+        return 1;
 }
+#endif
 
 /*
  * The following three routines simply manage the i_flock
diff --git a/fs/xfs/xfs_inode.c b/fs/xfs/xfs_inode.c
index ca12acb90394..cf0bb9c1d621 100644
--- a/fs/xfs/xfs_inode.c
+++ b/fs/xfs/xfs_inode.c
@@ -1291,7 +1291,7 @@ xfs_file_last_byte(
         xfs_fileoff_t   size_last_block;
         int             error;
 
-        ASSERT(ismrlocked(&(ip->i_iolock), MR_UPDATE | MR_ACCESS));
+        ASSERT(xfs_isilocked(ip, XFS_IOLOCK_EXCL|XFS_IOLOCK_SHARED));
 
         mp = ip->i_mount;
         /*
@@ -1402,7 +1402,7 @@ xfs_itruncate_start(
         bhv_vnode_t     *vp;
         int             error = 0;
 
-        ASSERT(ismrlocked(&ip->i_iolock, MR_UPDATE) != 0);
+        ASSERT(xfs_isilocked(ip, XFS_IOLOCK_EXCL));
         ASSERT((new_size == 0) || (new_size <= ip->i_size));
         ASSERT((flags == XFS_ITRUNC_DEFINITE) ||
                (flags == XFS_ITRUNC_MAYBE));
@@ -1528,8 +1528,7 @@ xfs_itruncate_finish(
         xfs_bmap_free_t free_list;
         int             error;
 
-        ASSERT(ismrlocked(&ip->i_iolock, MR_UPDATE) != 0);
-        ASSERT(ismrlocked(&ip->i_lock, MR_UPDATE) != 0);
+        ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL|XFS_IOLOCK_EXCL));
         ASSERT((new_size == 0) || (new_size <= ip->i_size));
         ASSERT(*tp != NULL);
         ASSERT((*tp)->t_flags & XFS_TRANS_PERM_LOG_RES);
@@ -1780,8 +1779,7 @@ xfs_igrow_start(
         xfs_fsize_t     new_size,
         cred_t          *credp)
 {
-        ASSERT(ismrlocked(&(ip->i_lock), MR_UPDATE) != 0);
-        ASSERT(ismrlocked(&(ip->i_iolock), MR_UPDATE) != 0);
+        ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL|XFS_IOLOCK_EXCL));
         ASSERT(new_size > ip->i_size);
 
         /*
@@ -1809,8 +1807,7 @@ xfs_igrow_finish(
         xfs_fsize_t     new_size,
         int             change_flag)
 {
-        ASSERT(ismrlocked(&(ip->i_lock), MR_UPDATE) != 0);
-        ASSERT(ismrlocked(&(ip->i_iolock), MR_UPDATE) != 0);
+        ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL|XFS_IOLOCK_EXCL));
         ASSERT(ip->i_transp == tp);
         ASSERT(new_size > ip->i_size);
 
@@ -2287,7 +2284,7 @@ xfs_ifree(
         xfs_dinode_t            *dip;
         xfs_buf_t               *ibp;
 
-        ASSERT(ismrlocked(&ip->i_lock, MR_UPDATE));
+        ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
         ASSERT(ip->i_transp == tp);
         ASSERT(ip->i_d.di_nlink == 0);
         ASSERT(ip->i_d.di_nextents == 0);
@@ -2746,7 +2743,7 @@ void
 xfs_ipin(
         xfs_inode_t     *ip)
 {
-        ASSERT(ismrlocked(&ip->i_lock, MR_UPDATE));
+        ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
 
         atomic_inc(&ip->i_pincount);
 }
@@ -2779,7 +2776,7 @@ __xfs_iunpin_wait(
 {
         xfs_inode_log_item_t    *iip = ip->i_itemp;
 
-        ASSERT(ismrlocked(&ip->i_lock, MR_UPDATE | MR_ACCESS));
+        ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL|XFS_ILOCK_SHARED));
         if (atomic_read(&ip->i_pincount) == 0)
                 return;
 
@@ -2829,7 +2826,7 @@ xfs_iextents_copy(
         xfs_fsblock_t           start_block;
 
         ifp = XFS_IFORK_PTR(ip, whichfork);
-        ASSERT(ismrlocked(&ip->i_lock, MR_UPDATE|MR_ACCESS));
+        ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL|XFS_ILOCK_SHARED));
         ASSERT(ifp->if_bytes > 0);
 
         nrecs = ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t);
@@ -3132,7 +3129,7 @@ xfs_iflush(
 
         XFS_STATS_INC(xs_iflush_count);
 
-        ASSERT(ismrlocked(&ip->i_lock, MR_UPDATE|MR_ACCESS));
+        ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL|XFS_ILOCK_SHARED));
         ASSERT(issemalocked(&(ip->i_flock)));
         ASSERT(ip->i_d.di_format != XFS_DINODE_FMT_BTREE ||
                ip->i_d.di_nextents > ip->i_df.if_ext_max);
@@ -3297,7 +3294,7 @@ xfs_iflush_int(
         int                     first;
 #endif
 
-        ASSERT(ismrlocked(&ip->i_lock, MR_UPDATE|MR_ACCESS));
+        ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL|XFS_ILOCK_SHARED));
         ASSERT(issemalocked(&(ip->i_flock)));
         ASSERT(ip->i_d.di_format != XFS_DINODE_FMT_BTREE ||
                ip->i_d.di_nextents > ip->i_df.if_ext_max);
diff --git a/fs/xfs/xfs_inode.h b/fs/xfs/xfs_inode.h
index 93c37697a72c..877d71adbc1e 100644
--- a/fs/xfs/xfs_inode.h
+++ b/fs/xfs/xfs_inode.h
@@ -386,20 +386,9 @@ xfs_iflags_test_and_clear(xfs_inode_t *ip, unsigned short flags)
 #define XFS_ILOCK_EXCL          (1<<2)
 #define XFS_ILOCK_SHARED        (1<<3)
 #define XFS_IUNLOCK_NONOTIFY    (1<<4)
-/*      #define XFS_IOLOCK_NESTED       (1<<5)  */
-#define XFS_EXTENT_TOKEN_RD     (1<<6)
-#define XFS_SIZE_TOKEN_RD       (1<<7)
-#define XFS_EXTSIZE_RD          (XFS_EXTENT_TOKEN_RD|XFS_SIZE_TOKEN_RD)
-#define XFS_WILLLEND            (1<<8)  /* Always acquire tokens for lending */
-#define XFS_EXTENT_TOKEN_WR     (XFS_EXTENT_TOKEN_RD | XFS_WILLLEND)
-#define XFS_SIZE_TOKEN_WR       (XFS_SIZE_TOKEN_RD | XFS_WILLLEND)
-#define XFS_EXTSIZE_WR          (XFS_EXTSIZE_RD | XFS_WILLLEND)
-/* TODO:XFS_SIZE_TOKEN_WANT     (1<<9) */
 
 #define XFS_LOCK_MASK           (XFS_IOLOCK_EXCL | XFS_IOLOCK_SHARED \
-                                | XFS_ILOCK_EXCL | XFS_ILOCK_SHARED \
-                                | XFS_EXTENT_TOKEN_RD | XFS_SIZE_TOKEN_RD \
-                                | XFS_WILLLEND)
+                                | XFS_ILOCK_EXCL | XFS_ILOCK_SHARED)
 
 /*
  * Flags for lockdep annotations.
@@ -483,6 +472,7 @@ void		xfs_ilock(xfs_inode_t *, uint);
 int             xfs_ilock_nowait(xfs_inode_t *, uint);
 void            xfs_iunlock(xfs_inode_t *, uint);
 void            xfs_ilock_demote(xfs_inode_t *, uint);
+int             xfs_isilocked(xfs_inode_t *, uint);
 void            xfs_iflock(xfs_inode_t *);
 int             xfs_iflock_nowait(xfs_inode_t *);
 uint            xfs_ilock_map_shared(xfs_inode_t *);
diff --git a/fs/xfs/xfs_inode_item.c b/fs/xfs/xfs_inode_item.c
index 93b5db453ea2..167b33f15772 100644
--- a/fs/xfs/xfs_inode_item.c
+++ b/fs/xfs/xfs_inode_item.c
@@ -547,7 +547,7 @@ STATIC void
 xfs_inode_item_pin(
         xfs_inode_log_item_t    *iip)
 {
-        ASSERT(ismrlocked(&(iip->ili_inode->i_lock), MR_UPDATE));
+        ASSERT(xfs_isilocked(iip->ili_inode, XFS_ILOCK_EXCL));
         xfs_ipin(iip->ili_inode);
 }
 
@@ -664,13 +664,13 @@ xfs_inode_item_unlock(
 
         ASSERT(iip != NULL);
         ASSERT(iip->ili_inode->i_itemp != NULL);
-        ASSERT(ismrlocked(&(iip->ili_inode->i_lock), MR_UPDATE));
+        ASSERT(xfs_isilocked(iip->ili_inode, XFS_ILOCK_EXCL));
         ASSERT((!(iip->ili_inode->i_itemp->ili_flags &
                   XFS_ILI_IOLOCKED_EXCL)) ||
-               ismrlocked(&(iip->ili_inode->i_iolock), MR_UPDATE));
+               xfs_isilocked(iip->ili_inode, XFS_IOLOCK_EXCL));
         ASSERT((!(iip->ili_inode->i_itemp->ili_flags &
                   XFS_ILI_IOLOCKED_SHARED)) ||
-               ismrlocked(&(iip->ili_inode->i_iolock), MR_ACCESS));
+               xfs_isilocked(iip->ili_inode, XFS_IOLOCK_SHARED));
         /*
          * Clear the transaction pointer in the inode.
          */
@@ -769,7 +769,7 @@ xfs_inode_item_pushbuf(
 
         ip = iip->ili_inode;
 
-        ASSERT(ismrlocked(&(ip->i_lock), MR_ACCESS));
+        ASSERT(xfs_isilocked(ip, XFS_ILOCK_SHARED));
 
         /*
          * The ili_pushbuf_flag keeps others from
@@ -857,7 +857,7 @@ xfs_inode_item_push(
 
         ip = iip->ili_inode;
 
-        ASSERT(ismrlocked(&(ip->i_lock), MR_ACCESS));
+        ASSERT(xfs_isilocked(ip, XFS_ILOCK_SHARED));
         ASSERT(issemalocked(&(ip->i_flock)));
         /*
          * Since we were able to lock the inode's flush lock and
diff --git a/fs/xfs/xfs_iomap.c b/fs/xfs/xfs_iomap.c
index fb3cf1191419..a2c3200a099f 100644
--- a/fs/xfs/xfs_iomap.c
+++ b/fs/xfs/xfs_iomap.c
@@ -196,14 +196,14 @@ xfs_iomap(
                 break;
         case BMAPI_WRITE:
                 xfs_iomap_enter_trace(XFS_IOMAP_WRITE_ENTER, ip, offset, count);
-                lockmode = XFS_ILOCK_EXCL|XFS_EXTSIZE_WR;
+                lockmode = XFS_ILOCK_EXCL;
                 if (flags & BMAPI_IGNSTATE)
                         bmapi_flags |= XFS_BMAPI_IGSTATE|XFS_BMAPI_ENTIRE;
                 xfs_ilock(ip, lockmode);
                 break;
         case BMAPI_ALLOCATE:
                 xfs_iomap_enter_trace(XFS_IOMAP_ALLOC_ENTER, ip, offset, count);
-                lockmode = XFS_ILOCK_SHARED|XFS_EXTSIZE_RD;
+                lockmode = XFS_ILOCK_SHARED;
                 bmapi_flags = XFS_BMAPI_ENTIRE;
 
                 /* Attempt non-blocking lock */
@@ -624,7 +624,7 @@ xfs_iomap_write_delay(
         int             prealloc, fsynced = 0;
         int             error;
 
-        ASSERT(ismrlocked(&ip->i_lock, MR_UPDATE) != 0);
+        ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
 
         /*
          * Make sure that the dquots are there. This doesn't hold
diff --git a/fs/xfs/xfs_trans_inode.c b/fs/xfs/xfs_trans_inode.c
index b8db1d5cde5a..4c70bf5e9985 100644
--- a/fs/xfs/xfs_trans_inode.c
+++ b/fs/xfs/xfs_trans_inode.c
@@ -111,13 +111,13 @@ xfs_trans_iget(
                  */
                 ASSERT(ip->i_itemp != NULL);
                 ASSERT(lock_flags & XFS_ILOCK_EXCL);
-                ASSERT(ismrlocked(&ip->i_lock, MR_UPDATE));
+                ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
                 ASSERT((!(lock_flags & XFS_IOLOCK_EXCL)) ||
-                       ismrlocked(&ip->i_iolock, MR_UPDATE));
+                       xfs_isilocked(ip, XFS_IOLOCK_EXCL));
                 ASSERT((!(lock_flags & XFS_IOLOCK_EXCL)) ||
                        (ip->i_itemp->ili_flags & XFS_ILI_IOLOCKED_EXCL));
                 ASSERT((!(lock_flags & XFS_IOLOCK_SHARED)) ||
-                       ismrlocked(&ip->i_iolock, (MR_UPDATE | MR_ACCESS)));
+                       xfs_isilocked(ip, XFS_IOLOCK_EXCL|XFS_IOLOCK_SHARED));
                 ASSERT((!(lock_flags & XFS_IOLOCK_SHARED)) ||
                        (ip->i_itemp->ili_flags & XFS_ILI_IOLOCKED_ANY));
 
@@ -185,7 +185,7 @@ xfs_trans_ijoin(
         xfs_inode_log_item_t    *iip;
 
         ASSERT(ip->i_transp == NULL);
-        ASSERT(ismrlocked(&ip->i_lock, MR_UPDATE));
+        ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
         ASSERT(lock_flags & XFS_ILOCK_EXCL);
         if (ip->i_itemp == NULL)
                 xfs_inode_item_init(ip, ip->i_mount);
@@ -232,7 +232,7 @@ xfs_trans_ihold(
 {
         ASSERT(ip->i_transp == tp);
         ASSERT(ip->i_itemp != NULL);
-        ASSERT(ismrlocked(&ip->i_lock, MR_UPDATE));
+        ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
 
         ip->i_itemp->ili_flags |= XFS_ILI_HOLD;
 }
@@ -257,7 +257,7 @@ xfs_trans_log_inode(
 
         ASSERT(ip->i_transp == tp);
         ASSERT(ip->i_itemp != NULL);
-        ASSERT(ismrlocked(&ip->i_lock, MR_UPDATE));
+        ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
 
         lidp = xfs_trans_find_item(tp, (xfs_log_item_t*)(ip->i_itemp));
         ASSERT(lidp != NULL);
diff --git a/fs/xfs/xfs_utils.c b/fs/xfs/xfs_utils.c
index 2b8dc7e40772..27075c9060ef 100644
--- a/fs/xfs/xfs_utils.c
+++ b/fs/xfs/xfs_utils.c
@@ -310,7 +310,7 @@ xfs_bump_ino_vers2(
 {
         xfs_mount_t     *mp;
 
-        ASSERT(ismrlocked (&ip->i_lock, MR_UPDATE));
+        ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
         ASSERT(ip->i_d.di_version == XFS_DINODE_VERSION_1);
 
         ip->i_d.di_version = XFS_DINODE_VERSION_2;
diff --git a/fs/xfs/xfs_vnodeops.c b/fs/xfs/xfs_vnodeops.c
index 637fc1a2bb44..322ba094dcc8 100644
--- a/fs/xfs/xfs_vnodeops.c
+++ b/fs/xfs/xfs_vnodeops.c
@@ -1305,7 +1305,7 @@ xfs_inactive_attrs(
         int             error;
         xfs_mount_t     *mp;
 
-        ASSERT(ismrlocked(&ip->i_iolock, MR_UPDATE));
+        ASSERT(xfs_isilocked(ip, XFS_IOLOCK_EXCL));
         tp = *tpp;
         mp = ip->i_mount;
         ASSERT(ip->i_d.di_forkoff != 0);
@@ -1776,7 +1776,7 @@ xfs_create(
          * It is locked (and joined to the transaction).
          */
 
-        ASSERT(ismrlocked (&ip->i_lock, MR_UPDATE));
+        ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
 
         /*
          * Now we join the directory inode to the transaction.  We do not do it