On Mon, Jun 19, 2006 at 07:28:33PM +0100, Al Viro wrote: > But now we have the buffer_heads on page 0 in the state inconsistent with > the reality - basically, fs/buffer.c helpers will assume that they are > _still_ in the second state (known to be in hole), while in the reality > they should be either in the first or in the third one (mapped to known > disk block or not known). > > It's not a fundamental problem; And if we'll write after that to 0th page, data with size <=page size, we can get garbage(not zeroes) on the rest of page. Definitely, after block allocation, we should touch pages from inode cache, which belongs to block except current page. >however, it does mean that using these > helpers means using library functions in situation they'd never been designed > for. IOW, you need very careful analysis of the assumptions made by > the entire bunch and, quite possibly, need versions modified for UFS. May be there is some incomprehension here, this series and all other my patches in -mm related to UFS is not introduced write support for UFS, they fixes bugs similar to which you point out in black corners of the existing implementation. Note: almost all such bugs related to touch blockdev's cache instead of inode's cache, and working with blockdev's buffer cache without take into consideration that it's also page cache). -- /Evgeniy - To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
