smatch reports fs/proc/proc_sysctl.c:32:18: warning: symbol 'sysctl_mount_point' was not declared. Should it be static? This variable is only used in its defining file, so it should be static. Signed-off-by: Tom Rix <trix@redhat.com> Reviewed-by: Kees Cook <keescook@chromium.org> Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
Pull sysctl updates from Luis Chamberlain: "The changes for sysctl are in line with prior efforts to stop usage of deprecated routines which incur recursion and also make it hard to remove the empty array element in each sysctl array declaration. The most difficult user to modify was parport which required a bit of re-thinking of how to declare shared sysctls there, Joel Granados has stepped up to the plate to do most of this work and eventual removal of register_sysctl_table(). That work ended up saving us about 1465 bytes according to bloat-o-meter. Since we gained a few bloat-o-meter karma points I moved two rather small sysctl arrays from kernel/sysctl.c leaving us only two more sysctl arrays to move left. Most changes have been tested on linux-next for about a month. The last straggler patches are a minor parport fix, changes to the sysctl kernel selftest so to verify correctness and prevent regressions for the future change he made to provide an alternative solution for the special sysctl mount point target which was using the now deprecated sysctl child element. This is all prep work to now finally be able to remove the empty array element in all sysctl declarations / registrations which is expected to save us a bit of bytes all over the kernel. That work will be tested early after v6.5-rc1 is out" * tag 'v6.5-rc1-sysctl-next' of git://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux: sysctl: replace child with an enumeration sysctl: Remove debugging dump_stack test_sysclt: Test for registering a mount point test_sysctl: Add an option to prevent test skip test_sysctl: Add an unregister sysctl test test_sysctl: Group node sysctl test under one func test_sysctl: Fix test metadata getters parport: plug a sysctl register leak sysctl: move security keys sysctl registration to its own file sysctl: move umh sysctl registration to its own file signal: move show_unhandled_signals sysctl to its own file sysctl: remove empty dev table sysctl: Remove register_sysctl_table sysctl: Refactor base paths registrations sysctl: stop exporting register_sysctl_table parport: Removed sysctl related defines parport: Remove register_sysctl_table from parport_default_proc_register parport: Remove register_sysctl_table from parport_device_proc_register parport: Remove register_sysctl_table from parport_proc_register parport: Move magic number "15" to a define
This is part of the effort to remove the empty element at the end of ctl_table structs. "child" was a deprecated elem in this struct and was being used to differentiate between two types of ctl_tables: "normal" and "permanently emtpy". What changed?: * Replace "child" with an enumeration that will have two values: the default (0) and the permanently empty (1). The latter is left at zero so when struct ctl_table is created with kzalloc or in a local context, it will have the zero value by default. We document the new enum with kdoc. * Remove the "empty child" check from sysctl_check_table * Remove count_subheaders function as there is no longer a need to calculate how many headers there are for every child * Remove the recursive call to unregister_sysctl_table as there is no need to traverse down the child tree any longer * Add a new SYSCTL_PERM_EMPTY_DIR binary flag * Remove the last remanence of child from partport/procfs.c Signed-off-by: Joel Granados <j.granados@samsung.com> Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
Remove unneeded dump_stack in __register_sysctl_table Signed-off-by: Joel Granados <j.granados@samsung.com> Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
Use copy_splice_read() for tty, procfs, kernfs and random files rather than going through generic_file_splice_read() as they just copy the file into the output buffer and don't splice pages. This avoids the need for them to have a ->read_folio() to satisfy filemap_splice_read(). Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> cc: Christoph Hellwig <hch@lst.de> cc: Jens Axboe <axboe@kernel.dk> cc: Al Viro <viro@zeniv.linux.org.uk> cc: John Hubbard <jhubbard@nvidia.com> cc: David Hildenbrand <david@redhat.com> cc: Matthew Wilcox <willy@infradead.org> cc: Miklos Szeredi <miklos@szeredi.hu> cc: Arnd Bergmann <arnd@arndb.de> cc: linux-block@vger.kernel.org cc: linux-fsdevel@vger.kernel.org cc: linux-mm@kvack.org Link: https://lore.kernel.org/r/20230522135018.2742245-13-dhowells@redhat.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
This is part of the general push to deprecate register_sysctl_paths and register_sysctl_table. After removing all the calling functions, we remove both the register_sysctl_table function and the documentation check that appeared in check-sysctl-docs awk script. We save 595 bytes with this change: ./scripts/bloat-o-meter vmlinux.1.refactor-base-paths vmlinux.2.remove-sysctl-table add/remove: 2/8 grow/shrink: 1/0 up/down: 1154/-1749 (-595) Function old new delta count_subheaders - 983 +983 unregister_sysctl_table 29 184 +155 __pfx_count_subheaders - 16 +16 __pfx_unregister_sysctl_table.part 16 - -16 __pfx_register_leaf_sysctl_tables.constprop 16 - -16 __pfx_count_subheaders.part 16 - -16 __pfx___register_sysctl_base 16 - -16 unregister_sysctl_table.part 136 - -136 __register_sysctl_base 478 - -478 register_leaf_sysctl_tables.constprop 524 - -524 count_subheaders.part 547 - -547 Total: Before=21257652, After=21257057, chg -0.00% [mcgrof: remove register_leaf_sysctl_tables and append_path too and add bloat-o-meter stats] Signed-off-by: Joel Granados <j.granados@samsung.com> Signed-off-by: Luis Chamberlain <mcgrof@kernel.org> Acked-by: Christian Brauner <brauner@kernel.org>
We make register_sysctl_table static because the only function calling it is in fs/proc/proc_sysctl.c (__register_sysctl_base). We remove it from the sysctl.h header and modify the documentation in both the header and proc_sysctl.c files to mention "register_sysctl" instead of "register_sysctl_table". This plus the commits that remove register_sysctl_table from parport save 217 bytes: ./scripts/bloat-o-meter .bsysctl/vmlinux.old .bsysctl/vmlinux.new add/remove: 0/1 grow/shrink: 5/1 up/down: 458/-675 (-217) Function old new delta __register_sysctl_base 8 286 +278 parport_proc_register 268 379 +111 parport_device_proc_register 195 247 +52 kzalloc.constprop 598 608 +10 parport_default_proc_register 62 69 +7 register_sysctl_table 291 - -291 parport_sysctl_template 1288 904 -384 Total: Before=8603076, After=8602859, chg -0.00% Signed-off-by: Joel Granados <j.granados@samsung.com> Reviewed-by: Luis Chamberlain <mcgrof@kernel.org> Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
The deprecation for register_sysctl_paths() is over. We can rejoice as
we nuke register_sysctl_paths(). The routine register_sysctl_table()
was the only user left of register_sysctl_paths(), so we can now just
open code and move the implementation over to what used to be
to __register_sysctl_paths().
The old dynamic struct ctl_table_set *set is now the point to
sysctl_table_root.default_set.
The old dynamic const struct ctl_path *path was being used in the
routine register_sysctl_paths() with a static:
static const struct ctl_path null_path[] = { {} };
Since this is a null path we can now just simplfy the old routine
and remove its use as its always empty.
This saves us a total of 230 bytes.
$ ./scripts/bloat-o-meter vmlinux.old vmlinux
add/remove: 2/7 grow/shrink: 1/1 up/down: 1015/-1245 (-230)
Function old new delta
register_leaf_sysctl_tables.constprop - 524 +524
register_sysctl_table 22 497 +475
__pfx_register_leaf_sysctl_tables.constprop - 16 +16
null_path 8 - -8
__pfx_register_sysctl_paths 16 - -16
__pfx_register_leaf_sysctl_tables 16 - -16
__pfx___register_sysctl_paths 16 - -16
__register_sysctl_base 29 12 -17
register_sysctl_paths 18 - -18
register_leaf_sysctl_tables 534 - -534
__register_sysctl_paths 620 - -620
Total: Before=21259666, After=21259436, chg -0.00%
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
Pull non-MM updates from Andrew Morton: "Mainly singleton patches all over the place. Series of note are: - updates to scripts/gdb from Glenn Washburn - kexec cleanups from Bjorn Helgaas" * tag 'mm-nonmm-stable-2023-04-27-16-01' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (50 commits) mailmap: add entries for Paul Mackerras libgcc: add forward declarations for generic library routines mailmap: add entry for Oleksandr ocfs2: reduce ioctl stack usage fs/proc: add Kthread flag to /proc/$pid/status ia64: fix an addr to taddr in huge_pte_offset() checkpatch: introduce proper bindings license check epoll: rename global epmutex scripts/gdb: add GDB convenience functions $lx_dentry_name() and $lx_i_dentry() scripts/gdb: create linux/vfs.py for VFS related GDB helpers uapi/linux/const.h: prefer ISO-friendly __typeof__ delayacct: track delays from IRQ/SOFTIRQ scripts/gdb: timerlist: convert int chunks to str scripts/gdb: print interrupts scripts/gdb: raise error with reduced debugging information scripts/gdb: add a Radix Tree Parser lib/rbtree: use '+' instead of '|' for setting color. proc/stat: remove arch_idle_time() checkpatch: check for misuse of the link tags checkpatch: allow Closes tags with links ...
Expand documentation to clarify:
o that paths don't need to exist for the new API callers
o clarify that we *require* callers to keep the memory of
the table around during the lifetime of the sysctls
o annotate routines we are trying to deprecate and later remove
Cc: stable@vger.kernel.org # v5.17
Cc: Christian Brauner <brauner@kernel.org>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>