[PATCH] m_growlock should be a mutex

[Christoph Hellwig <hch@xxxxxx>]

m_growlock only needs plain binary mutex semantics, so use a struct
mutex instead of a semaphore for it.


Signed-off-by: Christoph Hellwig <hch@xxxxxx>

Index: linux-2.6-xfs/fs/xfs/xfs_fsops.c
===================================================================
--- linux-2.6-xfs.orig/fs/xfs/xfs_fsops.c       2007-08-13 18:04:18.000000000 
+0200
+++ linux-2.6-xfs/fs/xfs/xfs_fsops.c    2007-08-13 18:04:26.000000000 +0200
@@ -433,10 +433,10 @@ xfs_growfs_data(
        xfs_growfs_data_t       *in)
 {
        int error;
-       if (!cpsema(&mp->m_growlock))
+       if (!mutex_trylock(&mp->m_growlock))
                return XFS_ERROR(EWOULDBLOCK);
        error = xfs_growfs_data_private(mp, in);
-       vsema(&mp->m_growlock);
+       mutex_unlock(&mp->m_growlock);
        return error;
 }
 
@@ -446,10 +446,10 @@ xfs_growfs_log(
        xfs_growfs_log_t        *in)
 {
        int error;
-       if (!cpsema(&mp->m_growlock))
+       if (!mutex_trylock(&mp->m_growlock))
                return XFS_ERROR(EWOULDBLOCK);
        error = xfs_growfs_log_private(mp, in);
-       vsema(&mp->m_growlock);
+       mutex_unlock(&mp->m_growlock);
        return error;
 }
 
Index: linux-2.6-xfs/fs/xfs/xfs_mount.c
===================================================================
--- linux-2.6-xfs.orig/fs/xfs/xfs_mount.c       2007-08-13 18:04:18.000000000 
+0200
+++ linux-2.6-xfs/fs/xfs/xfs_mount.c    2007-08-13 18:04:26.000000000 +0200
@@ -139,7 +139,7 @@ xfs_mount_init(void)
        AIL_LOCKINIT(&mp->m_ail_lock, "xfs_ail");
        spinlock_init(&mp->m_sb_lock, "xfs_sb");
        mutex_init(&mp->m_ilock);
-       initnsema(&mp->m_growlock, 1, "xfs_grow");
+       mutex_init(&mp->m_growlock);
        /*
         * Initialize the AIL.
         */
@@ -180,7 +180,7 @@ xfs_mount_free(
        AIL_LOCK_DESTROY(&mp->m_ail_lock);
        spinlock_destroy(&mp->m_sb_lock);
        mutex_destroy(&mp->m_ilock);
-       freesema(&mp->m_growlock);
+       mutex_destroy(&mp->m_growlock);
        if (mp->m_quotainfo)
                XFS_QM_DONE(mp);
 
Index: linux-2.6-xfs/fs/xfs/xfs_mount.h
===================================================================
--- linux-2.6-xfs.orig/fs/xfs/xfs_mount.h       2007-08-13 18:04:18.000000000 
+0200
+++ linux-2.6-xfs/fs/xfs/xfs_mount.h    2007-08-13 18:04:26.000000000 +0200
@@ -377,7 +377,7 @@ typedef struct xfs_mount {
        uint                    m_in_maxlevels; /* XFS_IN_MAXLEVELS */
        struct xfs_perag        *m_perag;       /* per-ag accounting info */
        struct rw_semaphore     m_peraglock;    /* lock for m_perag (pointer) */
-       sema_t                  m_growlock;     /* growfs mutex */
+       struct mutex            m_growlock;     /* growfs mutex */
        int                     m_fixedfsid[2]; /* unchanged for life of FS */
        uint                    m_dmevmask;     /* DMI events for this FS */
        __uint64_t              m_flags;        /* global mount flags */