user/sven/linux.git/fs/ramfs, branch v4.4.166

mm, fs: obey gfp_mapping for add_to_page_cache()

2015-10-16T18:42:28Z

Commit 6afdb859b710 ("mm: do not ignore mapping_gfp_mask in page cache allocation paths") has caught some users of hardcoded GFP_KERNEL used in the page cache allocation paths. This, however, wasn't complete and there were others which went unnoticed. Dave Chinner has reported the following deadlock for xfs on loop device: : With the recent merge of the loop device changes, I'm now seeing : XFS deadlock on my single CPU, 1GB RAM VM running xfs/073. : : The deadlocked is as follows: : : kloopd1: loop_queue_read_work : xfs_file_iter_read : lock XFS inode XFS_IOLOCK_SHARED (on image file) : page cache read (GFP_KERNEL) : radix tree alloc : memory reclaim : reclaim XFS inodes : log force to unpin inodes : : : xfs-cil/loop1: : xlog_cil_push : xlog_write : : xlog_state_get_iclog_space() : : : : kloopd1: loop_queue_write_work : xfs_file_write_iter : lock XFS inode XFS_IOLOCK_EXCL (on image file) : : : i.e. the kloopd, with it's split read and write work queues, has : introduced a dependency through memory reclaim. i.e. that writes : need to be able to progress for reads make progress. : : The problem, fundamentally, is that mpage_readpages() does a : GFP_KERNEL allocation, rather than paying attention to the inode's : mapping gfp mask, which is set to GFP_NOFS. : : The didn't used to happen, because the loop device used to issue : reads through the splice path and that does: : : error = add_to_page_cache_lru(page, mapping, index, : GFP_KERNEL & mapping_gfp_mask(mapping)); This has changed by commit aa4d86163e4 ("block: loop: switch to VFS ITER_BVEC"). This patch changes mpage_readpage{s} to follow gfp mask set for the mapping. There are, however, other places which are doing basically the same. lustre:ll_dir_filler is doing GFP_KERNEL from the function which apparently uses GFP_NOFS for other allocations so let's make this consistent. cifs:readpages_get_pages is called from cifs_readpages and __cifs_readpages_from_fscache called from the same path obeys mapping gfp. ramfs_nommu_expand_for_mapping is hardcoding GFP_KERNEL as well regardless it uses mapping_gfp_mask for the page allocation. ext4_mpage_readpages is the called from the page cache allocation path same as read_pages and read_cache_pages As I've noticed in my previous post I cannot say I would be happy about sprinkling mapping_gfp_mask all over the place and it sounds like we should drop gfp_mask argument altogether and use it internally in __add_to_page_cache_locked that would require all the filesystems to use mapping gfp consistently which I am not sure is the case here. From a quick glance it seems that some file system use it all the time while others are selective. Signed-off-by: Michal Hocko Reported-by: Dave Chinner Cc: "Theodore Ts'o" Cc: Ming Lei Cc: Andreas Dilger Cc: Oleg Drokin Cc: Al Viro Cc: Christoph Hellwig Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

VFS: normal filesystems (and lustre): d_inode() annotations

2015-04-15T19:06:57Z

that's the bulk of filesystem drivers dealing with inodes of their own Signed-off-by: David Howells Signed-off-by: Al Viro

make new_sync_{read,write}() static

2015-04-12T02:29:40Z

All places outside of core VFS that checked ->read and ->write for being NULL or called the methods directly are gone now, so NULL {read,write} with non-NULL {read,write}_iter will do the right thing in all cases. Signed-off-by: Al Viro

fs: remove mapping->backing_dev_info

2015-01-20T21:03:05Z

Now that we never use the backing_dev_info pointer in struct address_space we can simply remove it and save 4 to 8 bytes in every inode. Signed-off-by: Christoph Hellwig Acked-by: Ryusuke Konishi Reviewed-by: Tejun Heo Reviewed-by: Jan Kara Signed-off-by: Jens Axboe

fs: introduce f_op->mmap_capabilities for nommu mmap support

2015-01-20T21:02:58Z

Since "BDI: Provide backing device capability information [try #3]" the backing_dev_info structure also provides flags for the kind of mmap operation available in a nommu environment, which is entirely unrelated to it's original purpose. Introduce a new nommu-only file operation to provide this information to the nommu mmap code instead. Splitting this from the backing_dev_info structure allows to remove lots of backing_dev_info instance that aren't otherwise needed, and entirely gets rid of the concept of providing a backing_dev_info for a character device. It also removes the need for the mtd_inodefs filesystem. Signed-off-by: Christoph Hellwig Reviewed-by: Tejun Heo Acked-by: Brian Norris Signed-off-by: Jens Axboe

fs/ramfs/file-nommu.c: replace count*size kzalloc by kcalloc

2014-08-08T22:57:18Z

Signed-off-by: Fabian Frederick Cc: Axel Lin Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

->splice_write() via ->write_iter()

2014-06-12T04:18:51Z

iter_file_splice_write() - a ->splice_write() instance that gathers the pipe buffers, builds a bio_vec-based iov_iter covering those and feeds it to ->write_iter(). A bunch of simple cases coverted to that... [AV: fixed the braino spotted by Cyrill] Signed-off-by: Al Viro

write_iter variants of {__,}generic_file_aio_write()

2014-05-06T21:38:00Z

Signed-off-by: Al Viro

switch simple generic_file_aio_read() users to ->read_iter()

2014-05-06T21:37:55Z

Signed-off-by: Al Viro

fs/ramfs: move ramfs_aops to inode.c

2014-01-24T00:36:58Z

ramfs_aops is identical in file-mmu.c and file-nommu.c. Thus move it to fs/ramfs/inode.c and make it static. Signed-off-by: Axel Lin Cc: Al Viro Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds