kernel/fs/ext4/indirect.c, branch linux-5.1.y

ext4: cleanup bh release code in ext4_ind_remove_space()

2019-03-23T15:56:01Z

Currently, we are releasing the indirect buffer where we are done with it in ext4_ind_remove_space(), so we can see the brelse() and BUFFER_TRACE() everywhere. It seems fragile and hard to read, and we may probably forget to release the buffer some day. This patch cleans up the code by putting of the code which releases the buffers to the end of the function. Signed-off-by: zhangyi (F) Signed-off-by: Theodore Ts'o Reviewed-by: Jan Kara

ext4: brelse all indirect buffer in ext4_ind_remove_space()

2019-03-23T15:43:05Z

All indirect buffers get by ext4_find_shared() should be released no mater the branch should be freed or not. But now, we forget to release the lower depth indirect buffers when removing space from the same higher depth indirect block. It will lead to buffer leak and futher more, it may lead to quota information corruption when using old quota, consider the following case. - Create and mount an empty ext4 filesystem without extent and quota features, - quotacheck and enable the user & group quota, - Create some files and write some data to them, and then punch hole to some files of them, it may trigger the buffer leak problem mentioned above. - Disable quota and run quotacheck again, it will create two new aquota files and write the checked quota information to them, which probably may reuse the freed indirect block(the buffer and page cache was not freed) as data block. - Enable quota again, it will invoke vfs_load_quota_inode()->invalidate_bdev() to try to clean unused buffers and pagecache. Unfortunately, because of the buffer of quota data block is still referenced, quota code cannot read the up to date quota info from the device and lead to quota information corruption. This problem can be reproduced by xfstests generic/231 on ext3 file system or ext4 file system without extent and quota features. This patch fix this problem by releasing the missing indirect buffers, in ext4_ind_remove_space(). Reported-by: Hulk Robot Signed-off-by: zhangyi (F) Signed-off-by: Theodore Ts'o Reviewed-by: Jan Kara Cc: stable@kernel.org

ext4: annotate more implicit fall throughs

2019-02-21T15:51:27Z

There is a plan to build the kernel with -Wimplicit-fallthrough and these places in the code produced warnings (W=1). Fix them up. This commit remove the following warnings: fs/ext4/indirect.c:1182:6: warning: this statement may fall through [-Wimplicit-fallthrough=] fs/ext4/indirect.c:1188:6: warning: this statement may fall through [-Wimplicit-fallthrough=] fs/ext4/indirect.c:1432:6: warning: this statement may fall through [-Wimplicit-fallthrough=] fs/ext4/indirect.c:1440:6: warning: this statement may fall through [-Wimplicit-fallthrough=] Signed-off-by: Mathieu Malaterre Signed-off-by: Theodore Ts'o Reviewed-by: Andreas Dilger

ext4: fix hole length detection in ext4_ind_map_blocks()

2018-05-12T23:55:00Z

When ext4_ind_map_blocks() computes a length of a hole, it doesn't count with the fact that mapped offset may be somewhere in the middle of the completely empty subtree. In such case it will return too large length of the hole which then results in lseek(SEEK_DATA) to end up returning an incorrect offset beyond the end of the hole. Fix the problem by correctly taking offset within a subtree into account when computing a length of a hole. Fixes: facab4d9711e7aa3532cb82643803e8f1b9518e8 CC: stable@vger.kernel.org Reported-by: Jeff Mahoney Signed-off-by: Jan Kara Signed-off-by: Theodore Ts'o

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

2017-11-02T10:10:55Z

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 Reviewed-by: Philippe Ombredanne Reviewed-by: Thomas Gleixner Signed-off-by: Greg Kroah-Hartman

ext4: call journal revoke when freeing ea_inode blocks

2017-06-22T01:36:51Z

ea_inode contents are treated as metadata, that's why it is journaled during initial writes. Failing to call revoke during freeing could cause user data to be overwritten with original ea_inode contents during journal replay. Signed-off-by: Tahsin Erdogan Signed-off-by: Theodore Ts'o

ext4: refactor direct IO code

2016-05-13T04:44:16Z

Currently ext4 direct IO handling is split between ext4_ext_direct_IO() and ext4_ind_direct_IO(). However the extent based function calls into the indirect based one for some cases and for example it is not able to handle file extending. Previously it was not also properly handling retries in case of ENOSPC errors. With DAX things would get even more contrieved so just refactor the direct IO code and instead of indirect / extent split do the split to read vs writes. Signed-off-by: Jan Kara Signed-off-by: Theodore Ts'o

ext4: return hole from ext4_map_blocks()

2016-03-10T03:54:00Z

Currently, ext4_map_blocks() just returns 0 when it finds a hole and allocation is not requested. However we have all the information available to tell how large the hole actually is and there are callers of ext4_map_blocks() which would save some block-by-block hole iteration if they knew this information. So fill in struct ext4_map_blocks even for holes with the information we have. We keep returning 0 for holes to maintain backward compatibility of the function. Signed-off-by: Jan Kara Signed-off-by: Theodore Ts'o

ext4: rename and split get blocks functions

2016-03-09T04:08:10Z

Rename ext4_get_blocks_write() to ext4_get_blocks_unwritten() to better describe what it does. Also split out get blocks functions for direct IO. Later we move functionality from _ext4_get_blocks() there. There's no functional change in this patch. Signed-off-by: Jan Kara Signed-off-by: Theodore Ts'o

ext4: clean up feature test macros with predicate functions

2015-10-17T20:18:43Z

Create separate predicate functions to test/set/clear feature flags, thereby replacing the wordy old macros. Furthermore, clean out the places where we open-coded feature tests. Signed-off-by: Darrick J. Wong