vldb_check: remove unreferenced mh entries with -fix

When running vldb_check with -fix, clear any mh extent entries which
are set but are not referenced by an address entry in the
IpMappedAddr table.  These unreferenced entries already generated a
warning.  This commit adds the feature to clear the unreferenced mh
entries using vldb_check -fix option.

Change-Id: I941d714c825d7990083ecd15fd7bd9cd3b5917b3
Reviewed-on: http://gerrit.openafs.org/7616
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Derrick Brashear <shadow@dementix.org>

diff --git a/src/vlserver/vldb_check.c b/src/vlserver/vldb_check.c
index 164010c..dc6dedf 100644 (file)
--- a/src/vlserver/vldb_check.c
+++ b/src/vlserver/vldb_check.c
@@ -79,6 +79,12 @@ afs_int32 maxentries;
 int serveraddrs[MAXSERVERID + 2];
 u_char serverxref[MAXSERVERID + 2];  /**< to resolve cross-linked mh entries */
 
+struct mhinfo {
+    afs_uint32 addr;                   /**< vldb file record */
+    char orphan[VL_MHSRV_PERBLK];      /**< unreferenced mh enties */
+} mhinfo[VL_MAX_ADDREXTBLKS];
+
+
 /*  Used to control what goes to stdout based on quiet flag */
 void
 quiet_println(const char *fmt,...) {
@@ -336,18 +342,20 @@ writeheader(struct vlheader *headerp)
 }
 
 void
-readMH(afs_int32 addr, struct extentaddr *mhblockP)
+readMH(afs_uint32 addr, int block, struct extentaddr *mhblockP)
 {
     int i, j;
     struct extentaddr *e;
 
     vldbread(addr, (char *)mhblockP, VL_ADDREXTBLK_SIZE);
 
-    mhblockP->ex_count = ntohl(mhblockP->ex_count);
-    mhblockP->ex_hdrflags = ntohl(mhblockP->ex_hdrflags);
-    for (i = 0; i < VL_MAX_ADDREXTBLKS; i++)
-       mhblockP->ex_contaddrs[i] = ntohl(mhblockP->ex_contaddrs[i]);
-
+    if (block == 0) {
+        mhblockP->ex_count = ntohl(mhblockP->ex_count);
+        mhblockP->ex_hdrflags = ntohl(mhblockP->ex_hdrflags);
+        for (i = 0; i < VL_MAX_ADDREXTBLKS; i++) {
+           mhblockP->ex_contaddrs[i] = ntohl(mhblockP->ex_contaddrs[i]);
+        }
+    }
     for (i = 1; i < VL_MHSRV_PERBLK; i++) {
        e = &(mhblockP[i]);
 
@@ -452,6 +460,33 @@ readentry(afs_int32 addr, struct nvlentry *vlentryp, afs_int32 *type)
 }
 
 void
+writeMH(afs_int32 addr, int block, struct extentaddr *mhblockP)
+{
+    int i, j;
+    struct extentaddr *e;
+
+    if (verbose) {
+       quiet_println("Writing back MH block % at addr %u\n", block,  addr);
+    }
+    if (block == 0) {
+       mhblockP->ex_count = htonl(mhblockP->ex_count);
+       mhblockP->ex_hdrflags = htonl(mhblockP->ex_hdrflags);
+       for (i = 0; i < VL_MAX_ADDREXTBLKS; i++) {
+           mhblockP->ex_contaddrs[i] = htonl(mhblockP->ex_contaddrs[i]);
+       }
+    }
+    for (i = 1; i < VL_MHSRV_PERBLK; i++) {
+       e = &(mhblockP[i]);
+       /* hostuuid was not converted */
+       e->ex_uniquifier = htonl(e->ex_uniquifier);
+       for (j = 0; j < VL_MAXIPADDRS_PERMH; j++) {
+           e->ex_addrs[j] = htonl(e->ex_addrs[j]);
+       }
+    }
+    vldbwrite(addr, (char *)mhblockP, VL_ADDREXTBLK_SIZE);
+}
+
+void
 writeentry(afs_int32 addr, struct nvlentry *vlentryp)
 {
     int i;
@@ -818,7 +853,6 @@ CheckIpAddrs(struct vlheader *header)
     int mhblocks = 0;
     afs_int32 i, j, m, rindex;
     afs_int32 mhentries, regentries;
-    afs_uint32 caddrs[VL_MAX_ADDREXTBLKS];
     char mhblock[VL_ADDREXTBLK_SIZE];
     struct extentaddr *MHblock = (struct extentaddr *)mhblock;
     struct extentaddr *e;
@@ -834,7 +868,7 @@ CheckIpAddrs(struct vlheader *header)
        /* Read the first MH block and from it, gather the
         * addresses of all the mh blocks.
         */
-       readMH(header->SIT, MHblock);
+       readMH(header->SIT, 0, MHblock);
        if (MHblock->ex_hdrflags != VLCONTBLOCK) {
           log_error
                (VLDB_CHECK_ERROR,"Multihomed Block 0: Bad entry at %u: Not a valid multihomed block\n",
@@ -842,32 +876,32 @@ CheckIpAddrs(struct vlheader *header)
        }
 
        for (i = 0; i < VL_MAX_ADDREXTBLKS; i++) {
-           caddrs[i] = MHblock->ex_contaddrs[i];
+           mhinfo[i].addr = MHblock->ex_contaddrs[i];
        }
 
-       if (header->SIT != caddrs[0]) {
+       if (header->SIT != mhinfo[0].addr) {
           log_error
                (VLDB_CHECK_ERROR,"MH block does not point to self %u in header, %u in block\n",
-                header->SIT, caddrs[0]);
+                header->SIT, mhinfo[0].addr);
        }
 
        /* Now read each MH block and record it in the record array */
        for (i = 0; i < VL_MAX_ADDREXTBLKS; i++) {
-           if (!caddrs[i])
+           if (!mhinfo[i].addr)
                continue;
 
-           readMH(caddrs[i], MHblock);
+           readMH(mhinfo[i].addr, i, MHblock);
            if (MHblock->ex_hdrflags != VLCONTBLOCK) {
                log_error
                    (VLDB_CHECK_ERROR,"Multihomed Block 0: Bad entry at %u: Not a valid multihomed block\n",
                     header->SIT);
            }
 
-           rindex = caddrs[i] / sizeof(vlentry);
-           if (record[rindex].addr != caddrs[i] && record[rindex].addr) {
+           rindex = mhinfo[i].addr / sizeof(vlentry);
+           if (record[rindex].addr != mhinfo[i].addr && record[rindex].addr) {
                log_error
                    (VLDB_CHECK_ERROR,"INTERNAL VLDB_CHECK_ERROR: addresses %u and %u use same record slot %d\n",
-                    record[rindex].addr, caddrs[i], rindex);
+                    record[rindex].addr, mhinfo[i].addr, rindex);
            }
            if (record[rindex].type & FRC) {
                log_error
@@ -926,6 +960,7 @@ CheckIpAddrs(struct vlheader *header)
                if (ipaddrs) {
                    mhentries++;
                    if (ipindex == -1) {
+                       mhinfo[i].orphan[j] = 1;
                        log_error
                            (VLDB_CHECK_ERROR,"MH block %d, index %d: Not referenced by server addrs\n",
                             i, j);
@@ -972,7 +1007,7 @@ CheckIpAddrs(struct vlheader *header)
                   log_error
                        (VLDB_CHECK_ERROR,"IP Addr for entry %d: Multihome block is bad (%d)\n",
                         i, ((header->IpMappedAddr[i] & 0x00ff0000) >> 16));
-               if (caddrs[(header->IpMappedAddr[i] & 0x00ff0000) >> 16] == 0)
+               if (mhinfo[(header->IpMappedAddr[i] & 0x00ff0000) >> 16].addr == 0)
                    log_error(VLDB_CHECK_ERROR,"IP Addr for entry %d: No such multihome block (%d)\n",
                         i, ((header->IpMappedAddr[i] & 0x00ff0000) >> 16));
                if (((header->IpMappedAddr[i] & 0x0000ffff) > VL_MHSRV_PERBLK)
@@ -1137,6 +1172,7 @@ WorkerBee(struct cmd_syndesc *as, void *arock)
     maxentries = (header.vital_header.eofPtr / sizeof(vlentry)) + 1;
     record = calloc(maxentries, sizeof(struct er));
     memset(serveraddrs, 0, sizeof(serveraddrs));
+    memset(mhinfo, 0, sizeof(mhinfo));
     for (i = 0; i <= MAXSERVERID; i++) {
        serverxref[i] = BADSERVERID;
     }
@@ -1413,6 +1449,30 @@ WorkerBee(struct cmd_syndesc *as, void *arock)
                writeentry(record[i].addr, &vlentry);
            }
        }
+       else if (record[i].type & MH) {
+           int block, index;
+           char mhblock[VL_ADDREXTBLK_SIZE];
+           struct extentaddr *MHblock = (struct extentaddr *)mhblock;
+
+           if (fix) {
+               for (block = 0; block < VL_MAX_ADDREXTBLKS; block++) {
+                   if (mhinfo[block].addr == record[i].addr)
+                       break;
+               }
+               if (block == VL_MAX_ADDREXTBLKS) {
+                   continue;  /* skip orphaned extent block */
+               }
+               readMH(record[i].addr, block, MHblock);
+               for (index = 0; index < VL_MHSRV_PERBLK; index++) {
+                   if (mhinfo[block].orphan[index]) {
+                       quiet_println("FIX: Removing unreferenced mh entry; block %d, index %d\n",
+                               block, index);
+                       memset(&(MHblock[index]), 0, sizeof(struct extentaddr));
+                   }
+               }
+               writeMH(record[i].addr, block, MHblock);
+           }
+       }
     }
     if (fix) {
        reportHashChanges(&header, oldnamehash, oldidhash);