afs: WriteThroughDSlots: Avoid write error panic

[openafs.git] / src / afs / afs_dcache.c

diff --git a/src/afs/afs_dcache.c b/src/afs/afs_dcache.c
index 6ca9c1f..f71f459 100644 (file)
--- a/src/afs/afs_dcache.c
+++ b/src/afs/afs_dcache.c
@@ -2663,11 +2663,12 @@ afs_GetDCache(struct vcache *avc, afs_size_t abyte,
  * Environment:
  *     The afs_xdcache is write-locked through this whole affair.
  */
-void
+int
 afs_WriteThroughDSlots(void)
 {
     struct dcache *tdc;
     afs_int32 i, touchedit = 0;
+    int code = 0;
 
     struct afs_q DirtyQ, *tq;
 
@@ -2703,7 +2704,7 @@ afs_WriteThroughDSlots(void)
 
 #define DQTODC(q)      ((struct dcache *)(((char *) (q)) - sizeof(struct afs_q)))
 
-    for (tq = DirtyQ.prev; tq != &DirtyQ; tq = QPrev(tq)) {
+    for (tq = DirtyQ.prev; tq != &DirtyQ && code == 0; tq = QPrev(tq)) {
        tdc = DQTODC(tq);
        if (tdc->dflags & DFEntryMod) {
            int wrLock;
@@ -2714,9 +2715,15 @@ afs_WriteThroughDSlots(void)
            if (wrLock && (tdc->dflags & DFEntryMod)) {
                tdc->dflags &= ~DFEntryMod;
                ObtainWriteLock(&afs_xdcache, 620);
-               osi_Assert(afs_WriteDCache(tdc, 1) == 0);
+               code = afs_WriteDCache(tdc, 1);
                ReleaseWriteLock(&afs_xdcache);
-               touchedit = 1;
+                if (code) {
+                    /* We didn't successfully write out the dslot; make sure we
+                     * try again later */
+                    tdc->dflags |= DFEntryMod;
+                } else {
+                    touchedit = 1;
+                }
            }
            if (wrLock)
                ReleaseWriteLock(&tdc->lock);
@@ -2725,6 +2732,10 @@ afs_WriteThroughDSlots(void)
        afs_PutDCache(tdc);
     }
 
+    if (code) {
+        return code;
+    }
+
     ObtainWriteLock(&afs_xdcache, 617);
     if (!touchedit && (cacheDiskType != AFS_FCACHE_TYPE_MEM)) {
        /* Touch the file to make sure that the mtime on the file is kept
@@ -2737,6 +2748,7 @@ afs_WriteThroughDSlots(void)
        afs_osi_Write(afs_cacheInodep, 0, &theader, sizeof(theader));
     }
     ReleaseWriteLock(&afs_xdcache);
+    return 0;
 }
 
 /*