xnu-1504.15.3.tar.gz

[apple/xnu.git] / bsd / vfs / vfs_cluster.c

diff --git a/bsd/vfs/vfs_cluster.c b/bsd/vfs/vfs_cluster.c
index f1f9f649be47ba5e7b9d737fb3b4de517a7e08db..499056a3b5eb8605aa25e55289b80fee126a14fa 100644 (file)
--- a/bsd/vfs/vfs_cluster.c
+++ b/bsd/vfs/vfs_cluster.c
@@ -132,6 +132,7 @@ static lck_grp_t    *cl_mtx_grp;
 static lck_attr_t      *cl_mtx_attr;
 static lck_grp_attr_t   *cl_mtx_grp_attr;
 static lck_mtx_t       *cl_mtxp;
+static lck_mtx_t       *cl_transaction_mtxp;
 
 
 #define        IO_UNKNOWN      0
@@ -242,6 +243,11 @@ cluster_init(void) {
 
        if (cl_mtxp == NULL)
                panic("cluster_init: failed to allocate cl_mtxp");
+
+       cl_transaction_mtxp = lck_mtx_alloc_init(cl_mtx_grp, cl_mtx_attr);
+
+       if (cl_transaction_mtxp == NULL)
+               panic("cluster_init: failed to allocate cl_transaction_mtxp");
 }
 
 
@@ -510,26 +516,36 @@ cluster_iodone(buf_t bp, void *callback_arg)
        KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 20)) | DBG_FUNC_START,
                     cbp_head, bp->b_lblkno, bp->b_bcount, bp->b_flags, 0);
 
-       for (cbp = cbp_head; cbp; cbp = cbp->b_trans_next) {
-               /*
-                * all I/O requests that are part of this transaction
-                * have to complete before we can process it
-                */
-               if ( !(cbp->b_flags & B_DONE)) {
+       if (cbp_head->b_trans_next || !(cbp_head->b_flags & B_EOT)) {
+
+               lck_mtx_lock_spin(cl_transaction_mtxp);
+
+               bp->b_flags |= B_TDONE;
+               
+               for (cbp = cbp_head; cbp; cbp = cbp->b_trans_next) {
+                       /*
+                        * all I/O requests that are part of this transaction
+                        * have to complete before we can process it
+                        */
+                       if ( !(cbp->b_flags & B_TDONE)) {
 
+                               KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 20)) | DBG_FUNC_END,
+                                            cbp_head, cbp, cbp->b_bcount, cbp->b_flags, 0);
+
+                               lck_mtx_unlock(cl_transaction_mtxp);
+                               return 0;
+                       }
+                       if (cbp->b_flags & B_EOT)
+                               transaction_complete = TRUE;
+               }
+               lck_mtx_unlock(cl_transaction_mtxp);
+
+               if (transaction_complete == FALSE) {
                        KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 20)) | DBG_FUNC_END,
-                                    cbp_head, cbp, cbp->b_bcount, cbp->b_flags, 0);
+                                    cbp_head, 0, 0, 0, 0);
 
                        return 0;
                }
-               if (cbp->b_flags & B_EOT)
-                       transaction_complete = TRUE;
-       }
-       if (transaction_complete == FALSE) {
-               KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, 20)) | DBG_FUNC_END,
-                            cbp_head, 0, 0, 0, 0);
-
-               return 0;
        }
        error       = 0;
        total_size  = 0;
@@ -759,6 +775,14 @@ cluster_complete_transaction(buf_t *cbp_head, void *callback_arg, int *retval, i
                for (cbp = *cbp_head; cbp; cbp = cbp->b_trans_next)
                        buf_biowait(cbp);
        }
+       /*
+        * we've already waited on all of the I/Os in this transaction,
+        * so mark all of the buf_t's in this transaction as B_TDONE
+        * so that cluster_iodone sees the transaction as completed
+        */
+       for (cbp = *cbp_head; cbp; cbp = cbp->b_trans_next)
+               cbp->b_flags |= B_TDONE;
+
        error = cluster_iodone(*cbp_head, callback_arg);
 
        if ( !(flags & CL_ASYNC) && error && *retval == 0) {