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[[!tag open_issue_hurd]]

1. to run tmpfs as a regular user, /servers/default-pager must be executable by
    that user.  by default it seems to be set to read/write.

        $ sudo chmod ugo+x /servers/default-pager

    Then I get this error:

        tmpfs: /build/mbanck/hurd-20060825/build-tree/hurd/tmpfs/dir.c:62: diskfs_get_directs: Assertion `__builtin_offsetof (struct tmpfs_dirent, name) >= __builtin_offsetof (struct dirent, d_name)' failed.

2. i rearranged the struct tempfs_dirent in tmpfs.h to line up with the struct
    dirent.  now the assert passes at line 62 of dir.c passes.

         struct tmpfs_dirent
         {
           struct tmpfs_dirent *next;
           struct disknode *dn;
        +  char padding[3];
           uint8_t namelen;
           char name[0];
         };

    now ls works on an empty directory.
    you can touch files, and run `ls' on them.
    mkdir, rmdir works too.
    fsysopts works
    df works

3. creating a symlink fails.

    old patch to get symlinks working:

        http://www.mail-archive.com/bug-hurd@gnu.org/msg11844.html
        --- node.c.orig 2005-07-24 09:56:39.000000000 -0400
        +++ node.c      2005-07-24 09:55:46.000000000 -0400
        @@ -330,6 +330,7 @@
         create_symlink_hook (struct node *np, const char *target)
         {
           assert (np->dn->u.lnk == 0);
        +  np->dn_stat.st_size = strlen (target);
           if (np->dn_stat.st_size > 0)
             {
               const size_t size = np->dn_stat.st_size + 1;
        @@ -337,6 +338,7 @@
               if (np->dn->u.lnk == 0)
                return ENOSPC;
               memcpy (np->dn->u.lnk, target, size);
        +      np->dn->type = DT_LNK;
               adjust_used (size);
               recompute_blocks (np);
             }
        @@ -380,8 +382,6 @@
         error_t
         diskfs_truncate (struct node *np, off_t size)
         {
        -  if (np->allocsize <= size)
        -    return 0;
        
           if (np->dn->type == DT_LNK)
             {
        @@ -392,6 +392,9 @@
               return 0;
             }
        
        +  if (np->allocsize <= size)
        +    return 0;
        +
           assert (np->dn->type == DT_REG);
        
           if (default_pager == MACH_PORT_NULL)

    now symlinks work.

4. can't write data to a file


---

miscellaneous notes:

`diskfs_disk_name` could be `NULL`, but it is `"swap"`

using `default_pager_object_set_size (np->dn->u.reg.memobj, size);` to truncate and grow.

why are our blocks 512?  shouldn't it something else?  or at least settable?
or does [[libdiskfs]] demand this?

`diskfs_get_filemap_pager_struct (struct node *np)` returns null.
shouldn't it return `default_pager`?