xfs: remove the unused XFS_QMOPT_DQLOCK flag

The XFS_QMOPT_DQLOCK flag introduces major complexity in the quota subsystem
but isn't actually used anywhere.  So remove it and all the hazzles it
introduces.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Felix Blyakher <felixb@sgi.com>

3 files changed, 50 insertions, 113 deletions

diff --git a/fs/xfs/quota/xfs_qm.c b/fs/xfs/quota/xfs_qm.c
index 7a2beb64314f..fd0b383d72a5 100644
--- a/fs/xfs/quota/xfs_qm.c
+++ b/fs/xfs/quota/xfs_qm.c
@@ -632,7 +632,6 @@ xfs_qm_dqattach_one(
         xfs_dqid_t      id,
         uint            type,
         uint            doalloc,
-        uint            dolock,
         xfs_dquot_t     *udqhint, /* hint */
         xfs_dquot_t     **IO_idqpp)
 {
@@ -641,16 +640,16 @@ xfs_qm_dqattach_one(
 
         ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
         error = 0;
+
         /*
          * See if we already have it in the inode itself. IO_idqpp is
          * &i_udquot or &i_gdquot. This made the code look weird, but
          * made the logic a lot simpler.
          */
-        if ((dqp = *IO_idqpp)) {
-                if (dolock)
-                        xfs_dqlock(dqp);
+        dqp = *IO_idqpp;
+        if (dqp) {
                 xfs_dqtrace_entry(dqp, "DQATTACH: found in ip");
-                goto done;
+                return 0;
         }
 
         /*
@@ -659,38 +658,38 @@ xfs_qm_dqattach_one(
          * lookup by dqid (xfs_qm_dqget) by caching a group dquot inside
          * the user dquot.
          */
-        ASSERT(!udqhint || type == XFS_DQ_GROUP || type == XFS_DQ_PROJ);
-        if (udqhint && !dolock)
+        if (udqhint) {
+                ASSERT(type == XFS_DQ_GROUP || type == XFS_DQ_PROJ);
                 xfs_dqlock(udqhint);
 
-        /*
-         * No need to take dqlock to look at the id.
-         * The ID can't change until it gets reclaimed, and it won't
-         * be reclaimed as long as we have a ref from inode and we hold
-         * the ilock.
-         */
-        if (udqhint &&
-            (dqp = udqhint->q_gdquot) &&
-            (be32_to_cpu(dqp->q_core.d_id) == id)) {
-                ASSERT(XFS_DQ_IS_LOCKED(udqhint));
-                xfs_dqlock(dqp);
-                XFS_DQHOLD(dqp);
-                ASSERT(*IO_idqpp == NULL);
-                *IO_idqpp = dqp;
-                if (!dolock) {
+                /*
+                 * No need to take dqlock to look at the id.
+                 *
+                 * The ID can't change until it gets reclaimed, and it won't
+                 * be reclaimed as long as we have a ref from inode and we
+                 * hold the ilock.
+                 */
+                dqp = udqhint->q_gdquot;
+                if (dqp && be32_to_cpu(dqp->q_core.d_id) == id) {
+                        xfs_dqlock(dqp);
+                        XFS_DQHOLD(dqp);
+                        ASSERT(*IO_idqpp == NULL);
+                        *IO_idqpp = dqp;
+
                         xfs_dqunlock(dqp);
                         xfs_dqunlock(udqhint);
+                        return 0;
                 }
-                goto done;
-        }
-        /*
-         * We can't hold a dquot lock when we call the dqget code.
-         * We'll deadlock in no time, because of (not conforming to)
-         * lock ordering - the inodelock comes before any dquot lock,
-         * and we may drop and reacquire the ilock in xfs_qm_dqget().
-         */
-        if (udqhint)
+
+                /*
+                 * We can't hold a dquot lock when we call the dqget code.
+                 * We'll deadlock in no time, because of (not conforming to)
+                 * lock ordering - the inodelock comes before any dquot lock,
+                 * and we may drop and reacquire the ilock in xfs_qm_dqget().
+                 */
                 xfs_dqunlock(udqhint);
+        }
+
         /*
          * Find the dquot from somewhere. This bumps the
          * reference count of dquot and returns it locked.
@@ -698,48 +697,19 @@ xfs_qm_dqattach_one(
          * disk and we didn't ask it to allocate;
          * ESRCH if quotas got turned off suddenly.
          */
-        if ((error = xfs_qm_dqget(ip->i_mount, ip, id, type,
-                                 doalloc|XFS_QMOPT_DOWARN, &dqp))) {
-                if (udqhint && dolock)
-                        xfs_dqlock(udqhint);
-                goto done;
-        }
+        error = xfs_qm_dqget(ip->i_mount, ip, id, type, XFS_QMOPT_DOWARN, &dqp);
+        if (error)
+                return error;
 
         xfs_dqtrace_entry(dqp, "DQATTACH: found by dqget");
+
         /*
          * dqget may have dropped and re-acquired the ilock, but it guarantees
          * that the dquot returned is the one that should go in the inode.
          */
         *IO_idqpp = dqp;
-        ASSERT(dqp);
-        ASSERT(XFS_DQ_IS_LOCKED(dqp));
-        if (! dolock) {
-                xfs_dqunlock(dqp);
-                goto done;
-        }
-        if (! udqhint)
-                goto done;
-
-        ASSERT(udqhint);
-        ASSERT(dolock);
-        ASSERT(XFS_DQ_IS_LOCKED(dqp));
-        if (! xfs_qm_dqlock_nowait(udqhint)) {
-                xfs_dqunlock(dqp);
-                xfs_dqlock(udqhint);
-                xfs_dqlock(dqp);
-        }
-      done:
-#ifdef QUOTADEBUG
-        if (udqhint) {
-                if (dolock)
-                        ASSERT(XFS_DQ_IS_LOCKED(udqhint));
-        }
-        if (! error) {
-                if (dolock)
-                        ASSERT(XFS_DQ_IS_LOCKED(dqp));
-        }
-#endif
-        return error;
+        xfs_dqunlock(dqp);
+        return 0;
 }
 
 
@@ -754,24 +724,15 @@ xfs_qm_dqattach_one(
 STATIC void
 xfs_qm_dqattach_grouphint(
         xfs_dquot_t     *udq,
-        xfs_dquot_t     *gdq,
-        uint            locked)
+        xfs_dquot_t     *gdq)
 {
         xfs_dquot_t     *tmp;
 
-#ifdef QUOTADEBUG
-        if (locked) {
-                ASSERT(XFS_DQ_IS_LOCKED(udq));
-                ASSERT(XFS_DQ_IS_LOCKED(gdq));
-        }
-#endif
-        if (! locked)
-                xfs_dqlock(udq);
+        xfs_dqlock(udq);
 
         if ((tmp = udq->q_gdquot)) {
                 if (tmp == gdq) {
-                        if (! locked)
-                                xfs_dqunlock(udq);
+                        xfs_dqunlock(udq);
                         return;
                 }
 
@@ -781,8 +742,6 @@ xfs_qm_dqattach_grouphint(
                  * because the freelist lock comes before dqlocks.
                  */
                 xfs_dqunlock(udq);
-                if (locked)
-                        xfs_dqunlock(gdq);
                 /*
                  * we took a hard reference once upon a time in dqget,
                  * so give it back when the udquot no longer points at it
@@ -795,9 +754,7 @@ xfs_qm_dqattach_grouphint(
 
         } else {
                 ASSERT(XFS_DQ_IS_LOCKED(udq));
-                if (! locked) {
-                        xfs_dqlock(gdq);
-                }
+                xfs_dqlock(gdq);
         }
 
         ASSERT(XFS_DQ_IS_LOCKED(udq));
@@ -810,10 +767,9 @@ xfs_qm_dqattach_grouphint(
                 XFS_DQHOLD(gdq);
                 udq->q_gdquot = gdq;
         }
-        if (! locked) {
-                xfs_dqunlock(gdq);
-                xfs_dqunlock(udq);
-        }
+
+        xfs_dqunlock(gdq);
+        xfs_dqunlock(udq);
 }
 
 
@@ -821,8 +777,6 @@ xfs_qm_dqattach_grouphint(
  * Given a locked inode, attach dquot(s) to it, taking U/G/P-QUOTAON
  * into account.
  * If XFS_QMOPT_DQALLOC, the dquot(s) will be allocated if needed.
- * If XFS_QMOPT_DQLOCK, the dquot(s) will be returned locked. This option pretty
- * much made this code a complete mess, but it has been pretty useful.
  * If XFS_QMOPT_ILOCKED, then inode sent is already locked EXCL.
  * Inode may get unlocked and relocked in here, and the caller must deal with
  * the consequences.
@@ -851,7 +805,6 @@ xfs_qm_dqattach(
         if (XFS_IS_UQUOTA_ON(mp)) {
                 error = xfs_qm_dqattach_one(ip, ip->i_d.di_uid, XFS_DQ_USER,
                                                 flags & XFS_QMOPT_DQALLOC,
-                                                flags & XFS_QMOPT_DQLOCK,
                                                 NULL, &ip->i_udquot);
                 if (error)
                         goto done;
@@ -863,11 +816,9 @@ xfs_qm_dqattach(
                 error = XFS_IS_GQUOTA_ON(mp) ?
                         xfs_qm_dqattach_one(ip, ip->i_d.di_gid, XFS_DQ_GROUP,
                                                 flags & XFS_QMOPT_DQALLOC,
-                                                flags & XFS_QMOPT_DQLOCK,
                                                 ip->i_udquot, &ip->i_gdquot) :
                         xfs_qm_dqattach_one(ip, ip->i_d.di_projid, XFS_DQ_PROJ,
                                                 flags & XFS_QMOPT_DQALLOC,
-                                                flags & XFS_QMOPT_DQLOCK,
                                                 ip->i_udquot, &ip->i_gdquot);
                 /*
                  * Don't worry about the udquot that we may have
@@ -898,22 +849,13 @@ xfs_qm_dqattach(
                 /*
                  * Attach i_gdquot to the gdquot hint inside the i_udquot.
                  */
-                xfs_qm_dqattach_grouphint(ip->i_udquot, ip->i_gdquot,
-                                         flags & XFS_QMOPT_DQLOCK);
+                xfs_qm_dqattach_grouphint(ip->i_udquot, ip->i_gdquot);
         }
 
       done:
 
 #ifdef QUOTADEBUG
         if (! error) {
-                if (ip->i_udquot) {
-                        if (flags & XFS_QMOPT_DQLOCK)
-                                ASSERT(XFS_DQ_IS_LOCKED(ip->i_udquot));
-                }
-                if (ip->i_gdquot) {
-                        if (flags & XFS_QMOPT_DQLOCK)
-                                ASSERT(XFS_DQ_IS_LOCKED(ip->i_gdquot));
-                }
                 if (XFS_IS_UQUOTA_ON(mp))
                         ASSERT(ip->i_udquot);
                 if (XFS_IS_OQUOTA_ON(mp))
diff --git a/fs/xfs/quota/xfs_trans_dquot.c b/fs/xfs/quota/xfs_trans_dquot.c
index 99611381e740..447173bcf96d 100644
--- a/fs/xfs/quota/xfs_trans_dquot.c
+++ b/fs/xfs/quota/xfs_trans_dquot.c
@@ -624,10 +624,9 @@ xfs_trans_dqresv(
         xfs_qcnt_t      *resbcountp;
         xfs_quotainfo_t *q = mp->m_quotainfo;
 
-        if (! (flags & XFS_QMOPT_DQLOCK)) {
-                xfs_dqlock(dqp);
-        }
-        ASSERT(XFS_DQ_IS_LOCKED(dqp));
+
+        xfs_dqlock(dqp);
+
         if (flags & XFS_TRANS_DQ_RES_BLKS) {
                 hardlimit = be64_to_cpu(dqp->q_core.d_blk_hardlimit);
                 if (!hardlimit)
@@ -740,10 +739,8 @@ xfs_trans_dqresv(
         ASSERT(dqp->q_res_icount >= be64_to_cpu(dqp->q_core.d_icount));
 
 error_return:
-        if (! (flags & XFS_QMOPT_DQLOCK)) {
-                xfs_dqunlock(dqp);
-        }
-        return (error);
+        xfs_dqunlock(dqp);
+        return error;
 }
 
 
@@ -753,8 +750,7 @@ error_return:
  * grp/prj quotas is important, because this follows a both-or-nothing
  * approach.
  *
- * flags = XFS_QMOPT_DQLOCK indicate if dquot(s) need to be locked.
- *         XFS_QMOPT_FORCE_RES evades limit enforcement. Used by chown.
+ * flags = XFS_QMOPT_FORCE_RES evades limit enforcement. Used by chown.
  *         XFS_QMOPT_ENOSPC returns ENOSPC not EDQUOT.  Used by pquota.
  *         XFS_TRANS_DQ_RES_BLKS reserves regular disk blocks
  *         XFS_TRANS_DQ_RES_RTBLKS reserves realtime disk blocks
diff --git a/fs/xfs/xfs_quota.h b/fs/xfs/xfs_quota.h
index 48965ecaa155..63d41acf4533 100644
--- a/fs/xfs/xfs_quota.h
+++ b/fs/xfs/xfs_quota.h
@@ -185,7 +185,6 @@ typedef struct xfs_qoff_logformat {
  * to a single function. None of these XFS_QMOPT_* flags are meant to have
  * persistent values (ie. their values can and will change between versions)
  */
-#define XFS_QMOPT_DQLOCK        0x0000001 /* dqlock */
 #define XFS_QMOPT_DQALLOC       0x0000002 /* alloc dquot ondisk if needed */
 #define XFS_QMOPT_UQUOTA        0x0000004 /* user dquot requested */
 #define XFS_QMOPT_PQUOTA        0x0000008 /* project dquot requested */