kernel/fs/proc/inode.c, branch linux-4.16.y

proc: spread likely/unlikely a bit

2018-02-07T02:32:43Z

use_pde() is used at every open/read/write/... of every random /proc file. Negative refcount happens only if PDE is being deleted by module (read: never). So it gets "likely". unuse_pde() gets "unlikely" for the same reason. close_pdeo() gets unlikely as the completion is filled only if there is a race between PDE removal and close() (read: never ever). It even saves code on x86_64 defconfig: add/remove: 0/0 grow/shrink: 1/2 up/down: 2/-20 (-18) Function old new delta close_pdeo 183 185 +2 proc_reg_get_unmapped_area 119 111 -8 proc_reg_poll 85 73 -12 Link: http://lkml.kernel.org/r/20180104175657.GA5204@avx2 Signed-off-by: Alexey Dobriyan Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

fs/proc: use __ro_after_init

2018-02-07T02:32:43Z

/proc/self inode numbers, value of proc_inode_cache and st_nlink of /proc/$TGID are fixed constants. Link: http://lkml.kernel.org/r/20180103184707.GA31849@avx2 Signed-off-by: Alexey Dobriyan Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

Merge branch 'misc.poll' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

2018-01-31T01:58:07Z

Pull poll annotations from Al Viro: "This introduces a __bitwise type for POLL### bitmap, and propagates the annotations through the tree. Most of that stuff is as simple as 'make ->poll() instances return __poll_t and do the same to local variables used to hold the future return value'. Some of the obvious brainos found in process are fixed (e.g. POLLIN misspelled as POLL_IN). At that point the amount of sparse warnings is low and most of them are for genuine bugs - e.g. ->poll() instance deciding to return -EINVAL instead of a bitmap. I hadn't touched those in this series - it's large enough as it is. Another problem it has caught was eventpoll() ABI mess; select.c and eventpoll.c assumed that corresponding POLL### and EPOLL### were equal. That's true for some, but not all of them - EPOLL### are arch-independent, but POLL### are not. The last commit in this series separates userland POLL### values from the (now arch-independent) kernel-side ones, converting between them in the few places where they are copied to/from userland. AFAICS, this is the least disruptive fix preserving poll(2) ABI and making epoll() work on all architectures. As it is, it's simply broken on sparc - try to give it EPOLLWRNORM and it will trigger only on what would've triggered EPOLLWRBAND on other architectures. EPOLLWRBAND and EPOLLRDHUP, OTOH, are never triggered at all on sparc. With this patch they should work consistently on all architectures" * 'misc.poll' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (37 commits) make kernel-side POLL... arch-independent eventpoll: no need to mask the result of epi_item_poll() again eventpoll: constify struct epoll_event pointers debugging printk in sg_poll() uses %x to print POLL... bitmap annotate poll(2) guts 9p: untangle ->poll() mess ->si_band gets POLL... bitmap stored into a user-visible long field ring_buffer_poll_wait() return value used as return value of ->poll() the rest of drivers/*: annotate ->poll() instances media: annotate ->poll() instances fs: annotate ->poll() instances ipc, kernel, mm: annotate ->poll() instances net: annotate ->poll() instances apparmor: annotate ->poll() instances tomoyo: annotate ->poll() instances sound: annotate ->poll() instances acpi: annotate ->poll() instances crypto: annotate ->poll() instances block: annotate ->poll() instances x86: annotate ->poll() instances ...

fs: annotate ->poll() instances

2017-11-27T21:20:05Z

Signed-off-by: Al Viro

anntotate the places where ->poll() return values go

2017-11-27T21:19:53Z

Signed-off-by: Al Viro

->poll() methods should return __poll_t

2017-11-27T21:19:52Z

The most common place to find POLL... bitmaps: return values of ->poll() and its subsystem counterparts. Signed-off-by: Al Viro

Rename superblock flags (MS_xyz -> SB_xyz)

2017-11-27T21:05:09Z

This is a pure automated search-and-replace of the internal kernel superblock flags. The s_flags are now called SB_*, with the names and the values for the moment mirroring the MS_* flags that they're equivalent to. Note how the MS_xyz flags are the ones passed to the mount system call, while the SB_xyz flags are what we then use in sb->s_flags. The script to do this was: # places to look in; re security/*: it generally should *not* be # touched (that stuff parses mount(2) arguments directly), but # there are two places where we really deal with superblock flags. FILES="drivers/mtd drivers/staging/lustre fs ipc mm \ include/linux/fs.h include/uapi/linux/bfs_fs.h \ security/apparmor/apparmorfs.c security/apparmor/include/lib.h" # the list of MS_... constants SYMS="RDONLY NOSUID NODEV NOEXEC SYNCHRONOUS REMOUNT MANDLOCK \ DIRSYNC NOATIME NODIRATIME BIND MOVE REC VERBOSE SILENT \ POSIXACL UNBINDABLE PRIVATE SLAVE SHARED RELATIME KERNMOUNT \ I_VERSION STRICTATIME LAZYTIME SUBMOUNT NOREMOTELOCK NOSEC BORN \ ACTIVE NOUSER" SED_PROG= for i in $SYMS; do SED_PROG="$SED_PROG -e s/MS_$i/SB_$i/g"; done # we want files that contain at least one of MS_..., # with fs/namespace.c and fs/pnode.c excluded. L=$(for i in $SYMS; do git grep -w -l MS_$i $FILES; done| sort|uniq|grep -v '^fs/namespace.c'|grep -v '^fs/pnode.c') for f in $L; do sed -i $f $SED_PROG; done Requested-by: Al Viro Signed-off-by: Linus Torvalds

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

fs/proc/inode.c: remove cast from memory allocation

2017-05-09T00:15:10Z

Coccinelle emits this warning: WARNING: casting value returned by memory allocation function to (struct proc_inode *) is useless. Remove unnecessary cast. Link: http://lkml.kernel.org/r/1487745720-16967-1-git-send-email-me@tobin.cc Signed-off-by: Tobin C. Harding Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

procfs: use an enum for possible hidepid values

2017-02-25T01:46:56Z

Previously, the hidepid parameter was checked by comparing literal integers 0, 1, 2. Let's add a proper enum for this, to make the checking more expressive: 0 → HIDEPID_OFF 1 → HIDEPID_NO_ACCESS 2 → HIDEPID_INVISIBLE This changes the internal labelling only, the userspace-facing interface remains unmodified, and still works with literal integers 0, 1, 2. No functional changes. Link: http://lkml.kernel.org/r/1484572984-13388-2-git-send-email-djalal@gmail.com Signed-off-by: Lafcadio Wluiki Signed-off-by: Djalal Harouni Acked-by: Kees Cook Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds