kernel.git/drivers/lightnvm/pblk-write.c, branch linux-4.15.y

lightnvm: pblk: remove I/O dependency on write path

2017-10-13T14:34:57Z

pblk schedules user I/O, metadata I/O and erases on the write path in order to minimize collisions at the media level. Until now, there has been a dependency between user and metadata I/Os that could lead to a deadlock as both take the per-LUN semaphore to schedule submission. This path removes this dependency and guarantees forward progress at a per I/O granurality. Signed-off-by: Javier González Signed-off-by: Matias Bjørling Signed-off-by: Jens Axboe

lightnvm: pblk: refactor rqd alloc/free

2017-10-13T14:34:57Z

Refactor the rqd allocation and free functions so that all I/O types can use these helper functions. Signed-off-by: Javier González Signed-off-by: Matias Bjørling Signed-off-by: Jens Axboe

lightnvm: pblk: improve naming for internal req.

2017-10-13T14:34:57Z

Each request type sent to the LightNVM subsystem requires different metadata. Until now, we have tailored this metadata based on write, read and erase commands. However, pblk uses different metadata for internal writes that do not hit the write buffer. Instead of abusing the metadata for reads, create a new request type - internal write to improve code readability. In the process, create internal values for each I/O type instead of abusing the READ/WRITE macros, as suggested by Christoph. Signed-off-by: Javier González Signed-off-by: Matias Bjørling Signed-off-by: Jens Axboe

lightnvm: pblk: allocate bio size more accurately

2017-10-13T14:34:57Z

Wait until we know the exact number of ppas to be sent to the device, before allocating the bio. Signed-off-by: Javier González Signed-off-by: Matias Bjørling Signed-off-by: Jens Axboe

lightnvm: pblk: put bio on bio completion

2017-10-13T14:34:57Z

Simplify put bio by doing it on bio end_io instead of manually putting it on the completion path. Signed-off-by: Javier González Signed-off-by: Matias Bjørling Signed-off-by: Jens Axboe

lightnvm: pblk: remove checks on mempool alloc.

2017-10-13T14:34:57Z

As part of the mempool audit on pblk, remove unnecessary mempool allocation checks on mempools. Reported-by: Jens Axboe Signed-off-by: Javier González Signed-off-by: Matias Bjørling Signed-off-by: Jens Axboe

lightnvm: pblk: do not use a mempool for line bitmaps

2017-10-13T14:34:57Z

pblk holds two sector bitmaps: one to keep track of the mapped sectors while the line is active and another one to keep track of the invalid sectors. The latter is kept during the whole live of the line, until it is recycled. Since we cannot guarantee forward progress for the mempool in this case, get rid of the mempool and simply allocate memory through kmalloc. Reported-by: Jens Axboe Signed-off-by: Javier González Signed-off-by: Matias Bjørling Signed-off-by: Jens Axboe

lightnvm: pblk: simplify work_queue mempool

2017-10-13T14:34:57Z

In pblk, we have a mempool to allocate a generic structure that we pass along workqueues. This is heavily used in the GC path in order to have enough inflight reads and fully utilize the GC bandwidth. However, the current GC path copies data to the host memory and puts it back into the write buffer. This requires a vmalloc allocation for the data and a memory copy. Thus, guaranteeing the allocation by using a mempool for the structure in itself does not give us much. Until we implement support for vector copy to avoid moving data through the host, just allocate the workqueue structure using kmalloc. This allows us to have a much smaller mempool. Reported-by: Jens Axboe Signed-off-by: Javier González Signed-off-by: Matias Bjørling Signed-off-by: Jens Axboe

lightnvm: pblk: fix write I/O sync stat

2017-10-13T14:34:57Z

Fix stat counter to collect the right number of I/Os being synced on the completion path. Fixes: 0880a9aa2d91f ("lightnvm: pblk: delete redundant buffer pointer") Signed-off-by: Javier González Signed-off-by: Matias Bjørling Signed-off-by: Jens Axboe

lightnvm: pblk: free padded entries in write buffer

2017-10-13T14:34:57Z

When a REQ_FLUSH reaches pblk, the bio cannot be directly completed. Instead, data on the write buffer is flushed and the bio is completed on the completion pah. This might require some sectors to be padded in order to guarantee a successful write. This patch fixes a memory leak on the padded pages. A consequence of this bad free was that internal bios not containing data (only a flush) were not being completed. Fixes: a4bd217b4326 ("lightnvm: physical block device (pblk) target") Signed-off-by: Javier González Signed-off-by: Matias Bjørling Signed-off-by: Jens Axboe