cvs commit: src/sys/conf NOTES files options src/sys/fs/msdosfs msdosfs_fileno.c msdosfs_vfsops.c msdosfs_vnops.c msdosfsmount.h src/sys/modules/msdosfs Makefile

[Alfred Perlstein]

What are the implications of expanding the VFS API to take 64bit
inodes?

* Tim J. Robbins <tjr at FreeBSD.org> [040703 06:22] wrote:
> tjr         2004-07-03 13:22:39 UTC
> 
>   FreeBSD src repository
> 
>   Modified files:
>     sys/conf             NOTES files options 
>     sys/fs/msdosfs       msdosfs_vfsops.c msdosfs_vnops.c 
>                          msdosfsmount.h 
>     sys/modules/msdosfs  Makefile 
>   Added files:
>     sys/fs/msdosfs       msdosfs_fileno.c 
>   Log:
>   By popular request, add a workaround that allows large (>128GB or so)
>   FAT32 filesystems to be mounted, subject to some fairly serious limitations.
>   
>   This works by extending the internal pseudo-inode-numbers generated from
>   the file's starting cluster number to 64-bits, then creating a table
>   mapping these into arbitrary 32-bit inode numbers, which can fit in
>   struct dirent's d_fileno and struct vattr's va_fileid fields. The mappings
>   do not persist across unmounts or reboots, so it's not possible to export
>   these filesystems through NFS. The mapping table may grow to be rather
>   large, and may grow large enough to exhaust kernel memory on filesystems
>   with millions of files.
>   
>   Don't enable this option unless you understand the consequences.
>   
>   Revision  Changes    Path
>   1.1241    +12 -0     src/sys/conf/NOTES
>   1.923     +1 -0      src/sys/conf/files
>   1.460     +3 -0      src/sys/conf/options
>   1.1       +163 -0    src/sys/fs/msdosfs/msdosfs_fileno.c (new)
>   1.121     +14 -0     src/sys/fs/msdosfs/msdosfs_vfsops.c
>   1.148     +33 -13    src/sys/fs/msdosfs/msdosfs_vnops.c
>   1.33      +23 -1     src/sys/fs/msdosfs/msdosfsmount.h
>   1.21      +4 -1      src/sys/modules/msdosfs/Makefile

-- 
- Alfred Perlstein
- Research Engineering Development Inc.
- email: bright at mu.org cell: 408-480-4684