On Tue, 14 May 2013, Lukas Czerner wrote: > Date: Tue, 14 May 2013 18:37:14 +0200 > From: Lukas Czerner <lczerner@xxxxxxxxxx> > To: linux-mm@xxxxxxxxx > Cc: linux-kernel@xxxxxxxxxxxxxxx, linux-fsdevel@xxxxxxxxxxxxxxx, > linux-ext4@xxxxxxxxxxxxxxx, akpm@xxxxxxxxxxxxxxxxxxxx, hughd@xxxxxxxxxx, > lczerner@xxxxxxxxxx > Subject: [PATCH v4 00/20] change invalidatepage prototype to accept length Hi Ted, you've mentioned that you'll carry the changed in the ext4 tree. Are you going to take it for the next merge window ? However I still need some review on the mm part of the series, Andrew, Hugh, anyone ? Thanks! -Lukas > > Hi, > > This set of patches are aimed to allow truncate_inode_pages_range() handle > ranges which are not aligned at the end of the page. Currently it will > hit BUG_ON() when the end of the range is not aligned. Punch hole feature > however can benefit from this ability saving file systems some work not > forcing them to implement their own invalidate code to handle unaligned > ranges. > > In order for this to woke we need change ->invalidatepage() address space > operation to to accept range to invalidate by adding 'length' argument in > addition to 'offset'. This is different from my previous attempt to create > new aop ->invalidatepage_range (http://lwn.net/Articles/514828/) which I > reconsidered to be unnecessary. > > It would be for the best if this series could go through ext4 branch since > there are a lot of ext4 changes which are based on dev branch of ext4 > (git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4.git) > > For description purposes this patch set can be divided into following > groups: > > patch 0001: Change ->invalidatepage() prototype adding 'length' argument > and changing all the instances. In very simple cases file > system methods are completely adapted, otherwise only > prototype is changed and the rest will follow. This patch > also implement the 'range' invalidation in > block_invalidatepage(). > > patch 0002 - 0009: > Make the use of new 'length' argument in the file system > itself. Some file systems can take advantage of it trying > to invalidate only portion of the page if possible, some > can't, however none of the file systems currently attempt > to truncate non page aligned ranges. > > > patch 0010: Teach truncate_inode_pages_range() to handle non page aligned > ranges. > > patch 0011 - 0020: > Ext4 changes build on top of previous changes, simplifying > punch hole code. Not all changes are realated specifically > to invalidatepage() change, but all are related to the punch > hole feature. > > Even though this patch set would mainly affect functionality of the file > file systems implementing punch hole I've tested all the following file > system using xfstests without noticing any bugs related to this change. > > ext3, ext4, xfs, btrfs, gfs2 and reiserfs > > I've also tested block size < page size on ext4 with xfstests and fsx. > > > v3 -> v4: Some minor changes based on the reviews. Added two ext4 patches > as suggested by Jan Kara. > > Thanks! > -Lukas > > -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
