libext2fs: precompute FS UUID checksum seed

[tools/e2fsprogs.git] / lib / ext2fs / icount.c

diff --git a/lib/ext2fs/icount.c b/lib/ext2fs/icount.c
index 5203930..84b74a9 100644 (file)
--- a/lib/ext2fs/icount.c
+++ b/lib/ext2fs/icount.c
@@ -4,11 +4,12 @@
  * Copyright (C) 1997 Theodore Ts'o.
  *
  * %Begin-Header%
- * This file may be redistributed under the terms of the GNU Public
- * License.
+ * This file may be redistributed under the terms of the GNU Library
+ * General Public License, version 2.
  * %End-Header%
  */
 
+#include "config.h"
 #if HAVE_UNISTD_H
 #include <unistd.h>
 #endif
@@ -103,12 +104,12 @@ static errcode_t alloc_icount(ext2_filsys fs, int flags, ext2_icount_t *ret)
                return retval;
        memset(icount, 0, sizeof(struct ext2_icount));
 
-       retval = ext2fs_allocate_inode_bitmap(fs, 0, &icount->single);
+       retval = ext2fs_allocate_inode_bitmap(fs, "icount", &icount->single);
        if (retval)
                goto errout;
 
        if (flags & EXT2_ICOUNT_OPT_INCREMENT) {
-               retval = ext2fs_allocate_inode_bitmap(fs, 0,
+               retval = ext2fs_allocate_inode_bitmap(fs, "icount_inc",
                                                      &icount->multiple);
                if (retval)
                        goto errout;
@@ -179,6 +180,7 @@ errcode_t ext2fs_create_icount_tdb(ext2_filsys fs, char *tdb_dir,
        ext2_icount_t   icount;
        errcode_t       retval;
        char            *fn, uuid[40];
+       ext2_ino_t      num_inodes;
        int             fd;
 
        retval = alloc_icount(fs, flags,  &icount);
@@ -192,8 +194,18 @@ errcode_t ext2fs_create_icount_tdb(ext2_filsys fs, char *tdb_dir,
        sprintf(fn, "%s/%s-icount-XXXXXX", tdb_dir, uuid);
        fd = mkstemp(fn);
 
+       /*
+        * This is an overestimate of the size that we will need; the
+        * ideal value is the number of used inodes with a count
+        * greater than 1.  OTOH the times when we really need this is
+        * with the backup programs that use lots of hard links, in
+        * which case the number of inodes in use approaches the ideal
+        * value.
+        */
+       num_inodes = fs->super->s_inodes_count - fs->super->s_free_inodes_count;
+
        icount->tdb_fn = fn;
-       icount->tdb = tdb_open(fn, 0, TDB_CLEAR_IF_FIRST,
+       icount->tdb = tdb_open(fn, num_inodes, TDB_NOLOCK | TDB_NOSYNC,
                               O_RDWR | O_CREAT | O_TRUNC, 0600);
        if (icount->tdb) {
                close(fd);
@@ -339,9 +351,7 @@ static struct ext2_icount_el *insert_icount_el(ext2_icount_t icount,
 static struct ext2_icount_el *get_icount_el(ext2_icount_t icount,
                                            ext2_ino_t ino, int create)
 {
-       float   range;
        int     low, high, mid;
-       ext2_ino_t      lowval, highval;
 
        if (!icount || !icount->list)
                return 0;
@@ -363,31 +373,7 @@ static struct ext2_icount_el *get_icount_el(ext2_icount_t icount,
        low = 0;
        high = (int) icount->count-1;
        while (low <= high) {
-#if 0
-               mid = (low+high)/2;
-#else
-               if (low == high)
-                       mid = low;
-               else {
-                       /* Interpolate for efficiency */
-                       lowval = icount->list[low].ino;
-                       highval = icount->list[high].ino;
-
-                       if (ino < lowval)
-                               range = 0;
-                       else if (ino > highval)
-                               range = 1;
-                       else {
-                               range = ((float) (ino - lowval)) /
-                                       (highval - lowval);
-                               if (range > 0.9)
-                                       range = 0.9;
-                               if (range < 0.1)
-                                       range = 0.1;
-                       }
-                       mid = low + ((int) (range * (high-low)));
-               }
-#endif
+               mid = ((unsigned)low + (unsigned)high) >> 1;
                if (ino == icount->list[mid].ino) {
                        icount->cursor = mid+1;
                        return &icount->list[mid];
@@ -744,7 +730,7 @@ static void setup(void)
        initialize_ext2_error_table();
 
        memset(&param, 0, sizeof(param));
-       param.s_blocks_count = 12000;
+       ext2fs_blocks_count_set(&param, 12000);
 
        retval = ext2fs_initialize("test fs", EXT2_FLAG_64BITS, &param,
                                   test_io_manager, &test_fs);