Re: Getting FS access events

[H. Peter Anvin]

"Albert D. Cahalan" wrote:
> 
> H. Peter Anvin writes:
> 
> > This would leave no way (without introducing new interfaces) to write,
> > for example, the boot block on an ext2 filesystem.  Note that the
> > bootblock (defined as the first 1024 bytes) is not actually used by
> > the filesystem, although depending on the block size it may share a
> > block with the superblock (if blocksize > 1024).
> 
> The lack of coherency would screw this up anyway, doesn't it?
> You have a block device, soon to be in the page cache, and
> a superblock, also soon to be in the page cache. LILO writes to
> the block device, while the ext2 driver updates the superblock.
> Whatever gets written out last wins, and the other is lost.
> 

Albert, I *did* say "this better work or we have a problem."

	-hpa

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