dafs: prevent corruption in large fsstate.dat files

[openafs.git] / src / viced / serialize_state.c

diff --git a/src/viced/serialize_state.c b/src/viced/serialize_state.c
index c074304..aaf4988 100644 (file)
--- a/src/viced/serialize_state.c
+++ b/src/viced/serialize_state.c
@@ -20,8 +20,7 @@
 #include <afs/stds.h>
 
 #include <afs/opr.h>
-#include <lwp.h>
-#include <lock.h>
+#include <opr/lock.h>
 #include <afs/afsint.h>
 #include <afs/rxgen_consts.h>
 #include <afs/nfs.h>
@@ -75,7 +74,7 @@ static int fs_stateSizeFile(struct fs_dump_state * state);
 static int fs_stateResizeFile(struct fs_dump_state * state, size_t min_add);
 static int fs_stateTruncateFile(struct fs_dump_state * state);
 
-static int fs_stateMapFile(struct fs_dump_state * state);
+static int fs_stateMapFile(struct fs_dump_state * state, int preserve_flag);
 static int fs_stateUnmapFile(struct fs_dump_state * state);
 
 static int fs_stateIncCursor(struct fs_dump_state * state, size_t len);
@@ -341,7 +340,7 @@ fs_stateCreateDump(struct fs_dump_state * state)
        goto done;
     }
 
-    if (fs_stateMapFile(state)) {
+    if (fs_stateMapFile(state, 0)) {
        ViceLog(0, ("fs_stateCreateDump: failed to memory map state dump file '%s'\n",
                    state->fn));
        ret = 1;
@@ -466,7 +465,7 @@ fs_stateLoadDump(struct fs_dump_state * state)
     state->file_len = status.st_size;
 
 #ifdef FS_STATE_USE_MMAP
-    if (fs_stateMapFile(state)) {
+    if (fs_stateMapFile(state, 0)) {
        ViceLog(0, ("fs_stateLoadDump: failed to memory map state dump file '%s'\n",
                    state->fn));
        ret = 1;
@@ -735,7 +734,7 @@ fs_stateResizeFile(struct fs_dump_state * state, size_t min_add)
        goto done;
     }
 
-    if (fs_stateMapFile(state)) {
+    if (fs_stateMapFile(state, 1)) {
        ViceLog(0, ("fs_stateResizeFile: remapping memory mapped file failed\n"));
        ret = 1;
        goto done;
@@ -758,7 +757,7 @@ fs_stateTruncateFile(struct fs_dump_state * state)
 }
 
 static int
-fs_stateMapFile(struct fs_dump_state * state)
+fs_stateMapFile(struct fs_dump_state * state, int preserve_flag )
 {
     int ret = 0, flags;
 
@@ -792,8 +791,16 @@ fs_stateMapFile(struct fs_dump_state * state)
 
     state->mmap.size = state->file_len;
     state->mmap.cursor = state->mmap.map;
-    state->mmap.offset = 0;
 
+    if (preserve_flag) {
+       /* don't lose track of where we are during a file resize */
+       afs_foff_t curr_offset = state->mmap.offset;
+
+       state->mmap.offset = 0;
+       fs_stateIncCursor(state, curr_offset);
+    } else {           /* reset offset */
+       state->mmap.offset = 0;
+    }
     /* for state loading, accesses will be sequential, so let's give
      * the VM subsystem a heads up */
     if (state->mode == FS_STATE_LOAD_MODE) {