user/sven/linux.git/drivers/md/linear.c, branch v4.1.22

md: rename ->stop to ->free

2015-02-03T21:35:52Z

Now that the ->stop function only frees the private data, rename is accordingly. Also pass in the private pointer as an arg rather than using mddev->private. This flexibility will be useful in level_store(). Finally, don't clear ->private. It doesn't make sense to clear it seeing that isn't what we free, and it is no longer necessary to clear ->private (it was some time ago before ->to_remove was introduced). Setting ->to_remove in ->free() is a bit of a wart, but not a big problem at the moment. Signed-off-by: NeilBrown

md: split detach operation out from ->stop.

2015-02-03T21:35:52Z

Each md personality has a 'stop' operation which does two things: 1/ it finalizes some aspects of the array to ensure nothing is accessing the ->private data 2/ it frees the ->private data. All the steps in '1' can apply to all arrays and so can be performed in common code. This is useful as in the case where we change the personality which manages an array (in level_store()), it would be helpful to do step 1 early, and step 2 later. So split the 'step 1' functionality out into a new mddev_detach(). Signed-off-by: NeilBrown

md/linear: remove rcu protections in favour of suspend/resume

2015-02-03T21:35:52Z

The use of 'rcu' to protect accesses to ->private_data so that the ->private_data could be updated predates the introduction of mddev_suspend/mddev_resume. These are a cleaner mechanism for providing stability while swapping in a new ->private data - it is used by level_store() to support changing of raid levels. So get rid of the RCU stuff and just use mddev_suspend, mddev_resume. As these function call ->quiesce(), we add an empty function for linear just like for raid0. Signed-off-by: NeilBrown

md: make merge_bvec_fn more robust in face of personality changes.

2015-02-03T21:35:52Z

There is no locking around calls to merge_bvec_fn(), so it is possible that calls which coincide with a level (or personality) change could go wrong. So create a central dispatch point for these functions and use rcu_read_lock(). If the array is suspended, reject any merge that can be rejected. If not, we know it is safe to call the function. Signed-off-by: NeilBrown

md: make ->congested robust against personality changes.

2015-02-03T21:35:52Z

There is currently no locking around calls to the 'congested' bdi function. If called at an awkward time while an array is being converted from one level (or personality) to another, there is a tiny chance of running code in an unreferenced module etc. So add a 'congested' function to the md_personality operations structure, and call it with appropriate locking from a central 'mddev_congested'. When the array personality is changing the array will be 'suspended' so no IO is processed. If mddev_congested detects this, it simply reports that the array is congested, which is a safe guess. As mddev_suspend calls synchronize_rcu(), mddev_congested can avoid races by included the whole call inside an rcu_read_lock() region. This require that the congested functions for all subordinate devices can be run under rcu_lock. Fortunately this is the case. Signed-off-by: NeilBrown

md: remove unwanted white space from md.c

2014-10-14T02:08:29Z

My editor shows much of this is RED. Signed-off-by: NeilBrown

block: Introduce new bio_split()

2013-11-24T06:33:57Z

The new bio_split() can split arbitrary bios - it's not restricted to single page bios, like the old bio_split() (previously renamed to bio_pair_split()). It also has different semantics - it doesn't allocate a struct bio_pair, leaving it up to the caller to handle completions. Then convert the existing bio_pair_split() users to the new bio_split() - and also nvme, which was open coding bio splitting. (We have to take that BUG_ON() out of bio_integrity_trim() because this bio_split() needs to use it, and there's no reason it has to be used on bios marked as cloned; BIO_CLONED doesn't seem to have clearly documented semantics anyways.) Signed-off-by: Kent Overstreet Cc: Jens Axboe Cc: Martin K. Petersen Cc: Matthew Wilcox Cc: Keith Busch Cc: Vishal Verma Cc: Jiri Kosina Cc: Neil Brown

block: Rename bio_split() -> bio_pair_split()

2013-11-24T06:33:56Z

This is prep work for introducing a more general bio_split(). Signed-off-by: Kent Overstreet Cc: Jens Axboe Cc: NeilBrown Cc: Alasdair Kergon Cc: Lars Ellenberg Cc: Peter Osterlund Cc: Sage Weil

block: Abstract out bvec iterator

2013-11-24T06:33:47Z

Immutable biovecs are going to require an explicit iterator. To implement immutable bvecs, a later patch is going to add a bi_bvec_done member to this struct; for now, this patch effectively just renames things. Signed-off-by: Kent Overstreet Cc: Jens Axboe Cc: Geert Uytterhoeven Cc: Benjamin Herrenschmidt Cc: Paul Mackerras Cc: "Ed L. Cashin" Cc: Nick Piggin Cc: Lars Ellenberg Cc: Jiri Kosina Cc: Matthew Wilcox Cc: Geoff Levand Cc: Yehuda Sadeh Cc: Sage Weil Cc: Alex Elder Cc: ceph-devel@vger.kernel.org Cc: Joshua Morris Cc: Philip Kelleher Cc: Rusty Russell Cc: "Michael S. Tsirkin" Cc: Konrad Rzeszutek Wilk Cc: Jeremy Fitzhardinge Cc: Neil Brown Cc: Alasdair Kergon Cc: Mike Snitzer Cc: dm-devel@redhat.com Cc: Martin Schwidefsky Cc: Heiko Carstens Cc: linux390@de.ibm.com Cc: Boaz Harrosh Cc: Benny Halevy Cc: "James E.J. Bottomley" Cc: Greg Kroah-Hartman Cc: "Nicholas A. Bellinger" Cc: Alexander Viro Cc: Chris Mason Cc: "Theodore Ts'o" Cc: Andreas Dilger Cc: Jaegeuk Kim Cc: Steven Whitehouse Cc: Dave Kleikamp Cc: Joern Engel Cc: Prasad Joshi Cc: Trond Myklebust Cc: KONISHI Ryusuke Cc: Mark Fasheh Cc: Joel Becker Cc: Ben Myers Cc: xfs@oss.sgi.com Cc: Steven Rostedt Cc: Frederic Weisbecker Cc: Ingo Molnar Cc: Len Brown Cc: Pavel Machek Cc: "Rafael J. Wysocki" Cc: Herton Ronaldo Krzesinski Cc: Ben Hutchings Cc: Andrew Morton Cc: Guo Chao Cc: Tejun Heo Cc: Asai Thambi S P Cc: Selvan Mani Cc: Sam Bradshaw Cc: Wei Yongjun Cc: "Roger Pau Monné" Cc: Jan Beulich Cc: Stefano Stabellini Cc: Ian Campbell Cc: Sebastian Ott Cc: Christian Borntraeger Cc: Minchan Kim Cc: Jiang Liu Cc: Nitin Gupta Cc: Jerome Marchand Cc: Joe Perches Cc: Peng Tao Cc: Andy Adamson Cc: fanchaoting Cc: Jie Liu Cc: Sunil Mushran Cc: "Martin K. Petersen" Cc: Namjae Jeon Cc: Pankaj Kumar Cc: Dan Magenheimer Cc: Mel Gorman 6

block: Add bio_end_sector()

2013-03-23T21:15:29Z

Just a little convenience macro - main reason to add it now is preparing for immutable bio vecs, it'll reduce the size of the patch that puts bi_sector/bi_size/bi_idx into a struct bvec_iter. Signed-off-by: Kent Overstreet CC: Jens Axboe CC: Lars Ellenberg CC: Jiri Kosina CC: Alasdair Kergon CC: dm-devel@redhat.com CC: Neil Brown CC: Martin Schwidefsky CC: Heiko Carstens CC: linux-s390@vger.kernel.org CC: Chris Mason CC: Steven Whitehouse Acked-by: Steven Whitehouse