kernel/fs/btrfs/compression.c, branch linux-5.1.y

btrfs: Check the compression level before getting a workspace

2019-05-31T13:43:11Z

commit 2b90883c561ddcc641741c2e4df1f702a4f2acb8 upstream. When a file's compression property is set as zlib or zstd but leave the compression mount option not be set, that means btrfs will try to compress the file with default compression level. But in btrfs_compress_pages(), it calls get_workspace() with level = 0. This will return a workspace with a wrong compression level. For zlib, the compression level in the workspace will be 0 (that means "store only"). And for zstd, the compression in the workspace will be 1, not the default level 3. How to reproduce: mkfs -t btrfs /dev/sdb mount /dev/sdb /mnt/ mkdir /mnt/zlib btrfs property set /mnt/zlib/ compression zlib dd if=/dev/zero of=/mnt/zlib/compression-friendly-file-10M bs=1M count=10 sync btrfs-debugfs -f /mnt/zlib/compression-friendly-file-10M btrfs-debugfs output: * before: ... (258 9961472): ram 524288 disk 1106247680 disk_size 524288 file: ... extents 20 disk size 10485760 logical size 10485760 ratio 1.00 * after: ... (258 10354688): ram 131072 disk 14217216 disk_size 4096 file: ... extents 80 disk size 327680 logical size 10485760 ratio 32.00 The steps for zstd are similar, but need to put a debugging message to show the level of the return workspace in zstd_get_workspace(). This commit adds a check of the compression level before getting a workspace by set_level(). CC: stable@vger.kernel.org # 5.1+ Signed-off-by: Johnny Chang Reviewed-by: David Sterba Signed-off-by: David Sterba Signed-off-by: Greg Kroah-Hartman

Merge tag 'for-5.1/block-20190302' of git://git.kernel.dk/linux-block

2019-03-08T22:12:17Z

Pull block layer updates from Jens Axboe: "Not a huge amount of changes in this round, the biggest one is that we finally have Mings multi-page bvec support merged. Apart from that, this pull request contains: - Small series that avoids quiescing the queue for sysfs changes that match what we currently have (Aleksei) - Series of bcache fixes (via Coly) - Series of lightnvm fixes (via Mathias) - NVMe pull request from Christoph. Nothing major, just SPDX/license cleanups, RR mp policy (Hannes), and little fixes (Bart, Chaitanya). - BFQ series (Paolo) - Save blk-mq cpu -> hw queue mapping, removing a pointer indirection for the fast path (Jianchao) - fops->iopoll() added for async IO polling, this is a feature that the upcoming io_uring interface will use (Christoph, me) - Partition scan loop fixes (Dongli) - mtip32xx conversion from managed resource API (Christoph) - cdrom registration race fix (Guenter) - MD pull from Song, two minor fixes. - Various documentation fixes (Marcos) - Multi-page bvec feature. This brings a lot of nice improvements with it, like more efficient splitting, larger IOs can be supported without growing the bvec table size, and so on. (Ming) - Various little fixes to core and drivers" * tag 'for-5.1/block-20190302' of git://git.kernel.dk/linux-block: (117 commits) block: fix updating bio's front segment size block: Replace function name in string with __func__ nbd: propagate genlmsg_reply return code floppy: remove set but not used variable 'q' null_blk: fix checking for REQ_FUA block: fix NULL pointer dereference in register_disk fs: fix guard_bio_eod to check for real EOD errors blk-mq: use HCTX_TYPE_DEFAULT but not 0 to index blk_mq_tag_set->map block: optimize bvec iteration in bvec_iter_advance block: introduce mp_bvec_for_each_page() for iterating over page block: optimize blk_bio_segment_split for single-page bvec block: optimize __blk_segment_map_sg() for single-page bvec block: introduce bvec_nth_page() iomap: wire up the iopoll method block: add bio_set_polled() helper block: wire up block device iopoll method fs: add an iopoll method to struct file_operations loop: set GENHD_FL_NO_PART_SCAN after blkdev_reread_part() loop: do not print warn message if partition scan is successful block: bounce: make sure that bvec table is updated ...

btrfs: change set_level() to bound the level passed in

2019-02-25T13:13:32Z

Currently, the only user of set_level() is zlib which sets an internal workspace parameter. As level is now plumbed into get_workspace(), this can be handled there rather than separately. This repurposes set_level() to bound the level passed in so it can be used when setting the mounts compression level and as well as verifying the level before getting a workspace. The other benefit is this divides the meaning of compress(0) and get_workspace(0). The former means we want to use the default compression level of the compression type. The latter means we can use any workspace available. Signed-off-by: Dennis Zhou Reviewed-by: David Sterba Signed-off-by: David Sterba

btrfs: plumb level through the compression interface

2019-02-25T13:13:32Z

Zlib compression supports multiple levels, but doesn't require changing in how a workspace itself is created and managed. Zstd introduces a different memory requirement such that higher levels of compression require more memory. This requires changes in how the alloc()/get() methods work for zstd. This pach plumbs compression level through the interface as a parameter in preparation for zstd compression levels. This gives the compression types opportunity to create/manage based on the compression level. Reviewed-by: Nikolay Borisov Reviewed-by: Josef Bacik Signed-off-by: Dennis Zhou Reviewed-by: David Sterba Signed-off-by: David Sterba

btrfs: move to function pointers for get/put workspaces

2019-02-25T13:13:32Z

The previous patch added generic helpers for get_workspace() and put_workspace(). Now, we can migrate ownership of the workspace_manager to be in the compression type code as the compression code itself doesn't care beyond being able to get a workspace. The init/cleanup and get/put methods are abstracted so each compression algorithm can decide how they want to manage their workspaces. Reviewed-by: Josef Bacik Signed-off-by: Dennis Zhou Reviewed-by: David Sterba Signed-off-by: David Sterba

btrfs: add compression interface in (get/put)_workspace

2019-02-25T13:13:31Z

There are two levels of workspace management. First, alloc()/free() which are responsible for actually creating and destroy workspaces. Second, at a higher level, get()/put() which is the compression code asking for a workspace from a workspace_manager. The compression code shouldn't really care how it gets a workspace, but that it got a workspace. This adds get_workspace() and put_workspace() to be the higher level interface which is responsible for indexing into the appropriate compression type. It also introduces btrfs_put_workspace() and btrfs_get_workspace() to be the generic implementations of the higher interface. Reviewed-by: Josef Bacik Signed-off-by: Dennis Zhou Reviewed-by: David Sterba Signed-off-by: David Sterba

btrfs: add helper methods for workspace manager init and cleanup

2019-02-25T13:13:31Z

Workspace manager init and cleanup code is open coded inside a for loop over the compression types. This forces each compression type to rely on the same workspace manager implementation. This patch creates helper methods that will be the generic implementation for btrfs workspace management. Reviewed-by: Nikolay Borisov Reviewed-by: Josef Bacik Signed-off-by: Dennis Zhou Reviewed-by: David Sterba Signed-off-by: David Sterba

btrfs: unify compression ops with workspace_manager

2019-02-25T13:13:31Z

Make the workspace_manager own the interface operations rather than managing index-paired arrays for the workspace_manager and compression operations. Reviewed-by: Nikolay Borisov Reviewed-by: Josef Bacik Signed-off-by: Dennis Zhou Reviewed-by: David Sterba Signed-off-by: David Sterba

btrfs: manage heuristic workspace as index 0

2019-02-25T13:13:31Z

While the heuristic workspaces aren't really compression workspaces, they use the same interface for managing them. So rather than branching, let's just handle them once again as the index 0 compression type. Reviewed-by: Nikolay Borisov Reviewed-by: Josef Bacik Signed-off-by: Dennis Zhou Reviewed-by: David Sterba Signed-off-by: David Sterba

btrfs: rename workspaces_list to workspace_manager

2019-02-25T13:13:30Z

This is in preparation for zstd compression levels. As each level will require different size of workspace, workspaces_list is no longer a really fitting name. Reviewed-by: Nikolay Borisov Reviewed-by: Josef Bacik Signed-off-by: Dennis Zhou Reviewed-by: David Sterba Signed-off-by: David Sterba