cvs commit: src/sys/fs/msdosfs msdosfs_fat.c msdosfs_vfsops.c

[Bruce Evans]

bde         2007-08-03 23:13:51 UTC

  FreeBSD src repository

  Modified files:
    sys/fs/msdosfs       msdosfs_fat.c msdosfs_vfsops.c 
  Log:
  Oops, fix the fix for the i/o size of the fsinfo block.  Its log
  message explained why the size is 1 sector, but the code used a
  size of 1 cluster.
  
  I/o sizes larger than necessary may cause serious coherency problems
  in the buffer cache.  Here I think there were only minor efficiency
  problems, since a too-large fsinfo buffer could only get far enough
  to overlap buffers for the same vnode (the device vnode), so mappings
  are coherent at the page level although not at the buffer level, and
  the former is probably enough due to our limited use of the fsinfo
  buffer.
  
  Approved by:    re (kensmith)
  
  Revision  Changes    Path
  1.43      +1 -1      src/sys/fs/msdosfs/msdosfs_fat.c
  1.168     +1 -1      src/sys/fs/msdosfs/msdosfs_vfsops.c