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* ext4: fix up remaining files with SPDX cleanupsTheodore Ts'o2017-12-171-1/+1
| | | | | | | | | | | | | | | | | | | | A number of ext4 source files were skipped due because their copyright permission statements didn't match the expected text used by the automated conversion utilities. I've added SPDX tags for the rest. While looking at some of these files, I've noticed that we have quite a bit of variation on the licenses that were used --- in particular some of the Red Hat licenses on the jbd2 files use a GPL2+ license, and we have some files that have a LGPL-2.1 license (which was quite surprising). I've not attempted to do any license changes. Even if it is perfectly legal to relicense to GPL 2.0-only for consistency's sake, that should be done with ext4 developer community discussion. Signed-off-by: Theodore Ts'o <tytso@mit.edu>
* License cleanup: add SPDX GPL-2.0 license identifier to files with no licenseGreg Kroah-Hartman2017-11-021-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Many source files in the tree are missing licensing information, which makes it harder for compliance tools to determine the correct license. By default all files without license information are under the default license of the kernel, which is GPL version 2. Update the files which contain no license information with the 'GPL-2.0' SPDX license identifier. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. How this work was done: Patches were generated and checked against linux-4.14-rc6 for a subset of the use cases: - file had no licensing information it it. - file was a */uapi/* one with no licensing information in it, - file was a */uapi/* one with existing licensing information, Further patches will be generated in subsequent months to fix up cases where non-standard license headers were used, and references to license had to be inferred by heuristics based on keywords. The analysis to determine which SPDX License Identifier to be applied to a file was done in a spreadsheet of side by side results from of the output of two independent scanners (ScanCode & Windriver) producing SPDX tag:value files created by Philippe Ombredanne. Philippe prepared the base worksheet, and did an initial spot review of a few 1000 files. The 4.13 kernel was the starting point of the analysis with 60,537 files assessed. Kate Stewart did a file by file comparison of the scanner results in the spreadsheet to determine which SPDX license identifier(s) to be applied to the file. She confirmed any determination that was not immediately clear with lawyers working with the Linux Foundation. Criteria used to select files for SPDX license identifier tagging was: - Files considered eligible had to be source code files. - Make and config files were included as candidates if they contained >5 lines of source - File already had some variant of a license header in it (even if <5 lines). All documentation files were explicitly excluded. The following heuristics were used to determine which SPDX license identifiers to apply. - when both scanners couldn't find any license traces, file was considered to have no license information in it, and the top level COPYING file license applied. For non */uapi/* files that summary was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 11139 and resulted in the first patch in this series. If that file was a */uapi/* path one, it was "GPL-2.0 WITH Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 WITH Linux-syscall-note 930 and resulted in the second patch in this series. - if a file had some form of licensing information in it, and was one of the */uapi/* ones, it was denoted with the Linux-syscall-note if any GPL family license was found in the file or had no licensing in it (per prior point). Results summary: SPDX license identifier # files ---------------------------------------------------|------ GPL-2.0 WITH Linux-syscall-note 270 GPL-2.0+ WITH Linux-syscall-note 169 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17 LGPL-2.1+ WITH Linux-syscall-note 15 GPL-1.0+ WITH Linux-syscall-note 14 ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5 LGPL-2.0+ WITH Linux-syscall-note 4 LGPL-2.1 WITH Linux-syscall-note 3 ((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3 ((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1 and that resulted in the third patch in this series. - when the two scanners agreed on the detected license(s), that became the concluded license(s). - when there was disagreement between the two scanners (one detected a license but the other didn't, or they both detected different licenses) a manual inspection of the file occurred. - In most cases a manual inspection of the information in the file resulted in a clear resolution of the license that should apply (and which scanner probably needed to revisit its heuristics). - When it was not immediately clear, the license identifier was confirmed with lawyers working with the Linux Foundation. - If there was any question as to the appropriate license identifier, the file was flagged for further research and to be revisited later in time. In total, over 70 hours of logged manual review was done on the spreadsheet to determine the SPDX license identifiers to apply to the source files by Kate, Philippe, Thomas and, in some cases, confirmation by lawyers working with the Linux Foundation. Kate also obtained a third independent scan of the 4.13 code base from FOSSology, and compared selected files where the other two scanners disagreed against that SPDX file, to see if there was new insights. The Windriver scanner is based on an older version of FOSSology in part, so they are related. Thomas did random spot checks in about 500 files from the spreadsheets for the uapi headers and agreed with SPDX license identifier in the files he inspected. For the non-uapi files Thomas did random spot checks in about 15000 files. In initial set of patches against 4.14-rc6, 3 files were found to have copy/paste license identifier errors, and have been fixed to reflect the correct identifier. Additionally Philippe spent 10 hours this week doing a detailed manual inspection and review of the 12,461 patched files from the initial patch version early this week with: - a full scancode scan run, collecting the matched texts, detected license ids and scores - reviewing anything where there was a license detected (about 500+ files) to ensure that the applied SPDX license was correct - reviewing anything where there was no detection but the patch license was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied SPDX license was correct This produced a worksheet with 20 files needing minor correction. This worksheet was then exported into 3 different .csv files for the different types of files to be modified. These .csv files were then reviewed by Greg. Thomas wrote a script to parse the csv files and add the proper SPDX tag to the file, in the format that the file expected. This script was further refined by Greg based on the output to detect more types of files automatically and to distinguish between header and source .c files (which need different comment types.) Finally Greg ran the script using the .csv files to generate the patches. Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* ext4: move procfs registration code to fs/ext4/sysfs.cTheodore Ts'o2015-09-231-0/+2
| | | | | | | | | This allows us to refactor the procfs code, which saves a bit of compiled space. More importantly it isolates most of the procfs support code into a single file, so it's easier to #ifdef it out if the proc file system has been disabled. Signed-off-by: Theodore Ts'o <tytso@mit.edu>
* ext4: introduce aging to extent status treeJan Kara2014-11-251-4/+31
| | | | | | | | | | Introduce a simple aging to extent status tree. Each extent has a REFERENCED bit which gets set when the extent is used. Shrinker then skips entries with referenced bit set and clears the bit. Thus frequently used extents have higher chances of staying in memory. Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
* ext4: cleanup flag definitions for extent status treeJan Kara2014-11-251-32/+26
| | | | | | | | | | | Currently flags for extent status tree are defined twice, once shifted and once without a being shifted. Consolidate these definitions into one place and make some computations automatic to make adding flags less error prone. Compiler should be clever enough to figure out these are constants and generate the same code. Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
* ext4: move handling of list of shrinkable inodes into extent status codeJan Kara2014-11-251-2/+0
| | | | | | | | | | | | | Currently callers adding extents to extent status tree were responsible for adding the inode to the list of inodes with freeable extents. This is error prone and puts list handling in unnecessarily many places. Just add inode to the list automatically when the first non-delay extent is added to the tree and remove inode from the list when the last non-delay extent is removed. Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
* ext4: change LRU to round-robin in extent status tree shrinkerZheng Liu2014-11-251-4/+3
| | | | | | | | | | | | | | | | In this commit we discard the lru algorithm for inodes with extent status tree because it takes significant effort to maintain a lru list in extent status tree shrinker and the shrinker can take a long time to scan this lru list in order to reclaim some objects. We replace the lru ordering with a simple round-robin. After that we never need to keep a lru list. That means that the list needn't be sorted if the shrinker can not reclaim any objects in the first round. Cc: Andreas Dilger <adilger.kernel@dilger.ca> Signed-off-by: Zheng Liu <wenqing.lz@taobao.com> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
* ext4: track extent status tree shrinker delay staticticsZheng Liu2014-09-011-1/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This commit adds some statictics in extent status tree shrinker. The purpose to add these is that we want to collect more details when we encounter a stall caused by extent status tree shrinker. Here we count the following statictics: stats: the number of all objects on all extent status trees the number of reclaimable objects on lru list cache hits/misses the last sorted interval the number of inodes on lru list average: scan time for shrinking some objects the number of shrunk objects maximum: the inode that has max nr. of objects on lru list the maximum scan time for shrinking some objects The output looks like below: $ cat /proc/fs/ext4/sda1/es_shrinker_info stats: 28228 objects 6341 reclaimable objects 5281/631 cache hits/misses 586 ms last sorted interval 250 inodes on lru list average: 153 us scan time 128 shrunk objects maximum: 255 inode (255 objects, 198 reclaimable) 125723 us max scan time If the lru list has never been sorted, the following line will not be printed: 586ms last sorted interval If there is an empty lru list, the following lines also will not be printed: 250 inodes on lru list ... maximum: 255 inode (255 objects, 198 reclaimable) 0 us max scan time Meanwhile in this commit a new trace point is defined to print some details in __ext4_es_shrink(). Cc: Andreas Dilger <adilger.kernel@dilger.ca> Cc: Jan Kara <jack@suse.cz> Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Zheng Liu <wenqing.lz@taobao.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
* ext4: add ext4_es_store_pblock_status()Theodore Ts'o2014-02-191-0/+9
| | | | | | | | | | | | | | Avoid false positives by static code analysis tools such as sparse and coverity caused by the fact that we set the physical block, and then the status in the extent_status structure. It is also more efficient to set both of these values at once. Addresses-Coverity-Id: #989077 Addresses-Coverity-Id: #989078 Addresses-Coverity-Id: #1080722 Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> Reviewed-by: Zheng Liu <wenqing.lz@taobao.com>
* ext4: isolate ext4_extents.h fileZheng Liu2013-08-281-1/+0
| | | | | | | | | | | | | | | | | | | After applied the commit (4a092d73), we have reduced the number of source files that need to #include ext4_extents.h. But we can do better. This commit defines ext4_zeroout_es() in extents.c and move EXT_MAX_BLOCKS into ext4.h in order not to include ext4_extents.h in indirect.c and ioctl.c. Meanwhile we just need to include this file in extent_status.c when ES_AGGRESSIVE_TEST is defined. Otherwise, this commit removes a duplicated declaration in trace/events/ext4.h. After applied this patch, we just need to include ext4_extents.h file in {super,migrate,move_extents,extents}.c, and it is easy for us to define a new extent disk layout. Signed-off-by: Zheng Liu <wenqing.lz@taobao.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
* ext4: cache all of an extent tree's leaf block upon readingTheodore Ts'o2013-08-161-0/+3
| | | | | | | | | | | When we read in an extent tree leaf block from disk, arrange to have all of its entries cached. In nearly all cases the in-memory representation will be more compact than the on-disk representation in the buffer cache, and it allows us to get the information without having to traverse the extent tree for successive extents. Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> Reviewed-by: Zheng Liu <wenqing.lz@taobao.com>
* ext4: use unsigned int for es_status valuesTheodore Ts'o2013-08-161-20/+27
| | | | | | | | | | | Don't use an unsigned long long for the es_status flags; this requires that we pass 64-bit values around which is painful on 32-bit systems. Instead pass the extent status flags around using the low 4 bits of an unsigned int, and shift them into place when we are reading or writing es_pblk. Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> Reviewed-by: Zheng Liu <wenqing.lz@taobao.com>
* ext4: improve extent cache shrink mechanism to avoid to burn CPU timeZheng Liu2013-07-011-2/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Now we maintain an proper in-order LRU list in ext4 to reclaim entries from extent status tree when we are under heavy memory pressure. For keeping this order, a spin lock is used to protect this list. But this lock burns a lot of CPU time. We can use the following steps to trigger it. % cd /dev/shm % dd if=/dev/zero of=ext4-img bs=1M count=2k % mkfs.ext4 ext4-img % mount -t ext4 -o loop ext4-img /mnt % cd /mnt % for ((i=0;i<160;i++)); do truncate -s 64g $i; done % for ((i=0;i<160;i++)); do cp $i /dev/null &; done % perf record -a -g % perf report This commit tries to fix this problem. Now a new member called i_touch_when is added into ext4_inode_info to record the last access time for an inode. Meanwhile we never need to keep a proper in-order LRU list. So this can avoid to burns some CPU time. When we try to reclaim some entries from extent status tree, we use list_sort() to get a proper in-order list. Then we traverse this list to discard some entries. In ext4_sb_info, we use s_es_last_sorted to record the last time of sorting this list. When we traverse the list, we skip the inode that is newer than this time, and move this inode to the tail of LRU list. When the head of the list is newer than s_es_last_sorted, we will sort the LRU list again. In this commit, we break the loop if s_extent_cache_cnt == 0 because that means that all extents in extent status tree have been reclaimed. Meanwhile in this commit, ext4_es_{un}register_shrinker()'s prototype is changed to save a local variable in these functions. Reported-by: Dave Hansen <dave.hansen@intel.com> Signed-off-by: Zheng Liu <wenqing.lz@taobao.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
* ext4: fix fio regressionYan, Zheng2013-05-031-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We (Linux Kernel Performance project) found a regression introduced by commit: f7fec032aa ext4: track all extent status in extent status tree The commit causes about 20% performance decrease in fio random write test. Profiler shows that rb_next() uses a lot of CPU time. The call stack is: rb_next ext4_es_find_delayed_extent ext4_map_blocks _ext4_get_block ext4_get_block_write __blockdev_direct_IO ext4_direct_IO generic_file_direct_write __generic_file_aio_write ext4_file_write aio_rw_vect_retry aio_run_iocb do_io_submit sys_io_submit system_call_fastpath io_submit td_io_getevents io_u_queued_complete thread_main main __libc_start_main The cause is that ext4_es_find_delayed_extent() doesn't have an upper bound, it keeps searching until a delayed extent is found. When there are a lots of non-delayed entries in the extent state tree, ext4_es_find_delayed_extent() may uses a lot of CPU time. Reported-by: LKP project <lkp@linux.intel.com> Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com> Signed-off-by: Zheng Liu <wenqing.lz@taobao.com> Cc: "Theodore Ts'o" <tytso@mit.edu>
* ext4: update extent status tree after an extent is zeroed outZheng Liu2013-03-101-0/+3
| | | | | | | | | | | | | | | When we try to split an extent, this extent could be zeroed out and mark as initialized. But we don't know this in ext4_map_blocks because it only returns a length of allocated extent. Meanwhile we will mark this extent as uninitialized because we only check m_flags. This commit update extent status tree when we try to split an unwritten extent. We don't need to worry about the status of this extent because we always mark it as initialized. Signed-off-by: Zheng Liu <wenqing.lz@taobao.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> Cc: Dmitry Monakhov <dmonakhov@openvz.org>
* ext4: add self-testing infrastructure to do a sanity checkDmitry Monakhov2013-03-101-0/+6
| | | | | | | | | | | | | | | | | | | | | | | | This commit adds a self-testing infrastructure like extent tree does to do a sanity check for extent status tree. After status tree is as a extent cache, we'd better to make sure that it caches right result. After applied this commit, we will get a lot of messages when we run xfstests as below. ... kernel: ES len assertation failed for inode: 230 retval 1 != map->m_len 3 in ext4_map_blocks (allocation) ... kernel: ES cache assertation failed for inode: 230 es_cached ex [974/2/4781/20] != found ex [974/1/4781/1000] ... kernel: ES insert assertation failed for inode: 635 ex_status [0/45/21388/w] != es_status [44/1/21432/u] ... Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org> Signed-off-by: Zheng Liu <wenqing.lz@taobao.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
* ext4: fix extent status tree regression for file systems > 512GBTheodore Ts'o2013-02-271-8/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | This fixes a regression introduced by commit f7fec032aa782. The problem was that the extents status flags caused us to mask out block numbers smaller than 2**28 blocks. Since we didn't test with file systems smaller than 512GB, we didn't notice this during the development cycle. A typical failure looks like this: EXT4-fs error (device sdb1): htree_dirblock_to_tree:919: inode #172235804: block 152052301: comm ls: bad entry in directory: rec_len is smaller than minimal - offset=0(0), inode=0, rec_len=0, name_len=0 ... where 'debugfs -R "stat <172235804>" /dev/sdb1' reports that the inode has block number 688923213. When viewed in hex, block number 152052301 (from the syslog) is 0x910224D, while block number 688923213 is 0x2910224D. Note the missing "0x20000000" in the block number. Reported-by: Markus Trippelsdorf <markus@trippelsdorf.de> Verified-by: Markus Trippelsdorf <markus@trippelsdorf.de> Reported-by: Dave Jones <davej@redhat.com> Verified-by: Dave Jones <davej@redhat.com> Cc: Zheng Liu <gnehzuil.liu@gmail.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
* ext4: reclaim extents from extent status treeZheng Liu2013-02-181-0/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | Although extent status is loaded on-demand, we also need to reclaim extent from the tree when we are under a heavy memory pressure because in some cases fragmented extent tree causes status tree costs too much memory. Here we maintain a lru list in super_block. When the extent status of an inode is accessed and changed, this inode will be move to the tail of the list. The inode will be dropped from this list when it is cleared. In the inode, a counter is added to count the number of cached objects in extent status tree. Here only written/unwritten/hole extent is counted because delayed extent doesn't be reclaimed due to fiemap, bigalloc and seek_data/hole need it. The counter will be increased as a new extent is allocated, and it will be decreased as a extent is freed. In this commit we use normal shrinker framework to reclaim memory from the status tree. ext4_es_reclaim_extents_count() traverses the lru list to count the number of reclaimable extents. ext4_es_shrink() tries to reclaim written/unwritten/hole extents from extent status tree. The inode that has been shrunk is moved to the tail of lru list. Signed-off-by: Zheng Liu <wenqing.lz@taobao.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> Cc: Jan kara <jack@suse.cz>
* ext4: lookup block mapping in extent status treeZheng Liu2013-02-181-0/+2
| | | | | | | | | | | | | | | | | | | After tracking all extent status, we already have a extent cache in memory. Every time we want to lookup a block mapping, we can first try to lookup it in extent status tree to avoid a potential disk I/O. A new function called ext4_es_lookup_extent is defined to finish this work. When we try to lookup a block mapping, we always call ext4_map_blocks and/or ext4_da_map_blocks. So in these functions we first try to lookup a block mapping in extent status tree. A new flag EXT4_GET_BLOCKS_NO_PUT_HOLE is used in ext4_da_map_blocks in order not to put a hole into extent status tree because this hole will be converted to delayed extent in the tree immediately. Signed-off-by: Zheng Liu <wenqing.lz@taobao.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> Cc: Jan kara <jack@suse.cz>
* ext4: rename and improbe ext4_es_find_extent()Zheng Liu2013-02-181-2/+2
| | | | | | | | | | | This commit renames ext4_es_find_extent with ext4_es_find_delayed_extent and improve this function. First, we split input and output parameter. Second, this function never return the first block of the next delayed extent after 'es'. Signed-off-by: Zheng Liu <wenqing.lz@taobao.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> Cc: Jan kara <jack@suse.cz>
* ext4: add physical block and status member into extent status treeZheng Liu2013-02-181-1/+63
| | | | | | | | | | | | | | | This commit adds two members in extent_status structure to let it record physical block and extent status. Here es_pblk is used to record both of them because physical block only has 48 bits. So extent status could be stashed into it so that we can save some memory. Now written, unwritten, delayed and hole are defined as status. Due to new member is added into extent status tree, all interfaces need to be adjusted. Signed-off-by: Zheng Liu <wenqing.lz@taobao.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> Reviewed-by: Jan Kara <jack@suse.cz>
* ext4: refine extent status treeZheng Liu2013-02-181-4/+4
| | | | | | | | | | | | | | | | | | | | | | This commit refines the extent status tree code. 1) A prefix 'es_' is added to to the extent status tree structure members. 2) Refactored es_remove_extent() so that __es_remove_extent() can be used by es_insert_extent() to remove the old extent entry(-ies) before inserting a new one. 3) Rename extent_status_end() to ext4_es_end() 4) ext4_es_can_be_merged() is define to check whether two extents can be merged or not. 5) Update and clarified comments. Signed-off-by: Zheng Liu <wenqing.lz@taobao.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> Reviewed-by: Jan Kara <jack@suse.cz>
* ext4: add operations on extent status treeZheng Liu2012-11-081-0/+20
| | | | | | | | | | | This patch adds operations on a extent status tree. CC: Lukas Czerner <lczerner@redhat.com> Signed-off-by: Yongqiang Yang <xiaoqiangnk@gmail.com> Signed-off-by: Allison Henderson <achender@linux.vnet.ibm.com> Signed-off-by: Hugh Dickins <hughd@google.com> Signed-off-by: Zheng Liu <wenqing.lz@taobao.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
* ext4: add data structures for the extent status treeZheng Liu2012-11-081-0/+25
This patch adds two structures that supports extent status tree, extent_status and ext4_es_tree. Currently extent_status is used to track a delay extent for an inode, which record the start block and the length of the delay extent. ext4_es_tree is used to store all extent_status for an inode in memory. Signed-off-by: Yongqiang Yang <xiaoqiangnk@gmail.com> Signed-off-by: Allison Henderson <achender@linux.vnet.ibm.com> Signed-off-by: Zheng Liu <wenqing.lz@taobao.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>