linux/fs/kernfs
Al Viro c1feab95e0 add a string-to-qstr constructor
Quite a few places want to build a struct qstr by given string;
it would be convenient to have a primitive doing that, rather
than open-coding it via QSTR_INIT().

The closest approximation was in bcachefs, but that expands to
initializer list - {.len = strlen(string), .name = string}.
It would be more useful to have it as compound literal -
(struct qstr){.len = strlen(string), .name = string}.

Unlike initializer list it's a valid expression.  What's more,
it's a valid lvalue - it's an equivalent of anonymous local
variable with such initializer, so the things like
	path->dentry = d_alloc_pseudo(mnt->mnt_sb, &QSTR(name));
are valid.  It can also be used as initializer, with identical
effect -
	struct qstr x = (struct qstr){.name = s, .len = strlen(s)};
is equivalent to
	struct qstr anon_variable = {.name = s, .len = strlen(s)};
	struct qstr x = anon_variable;
	// anon_variable is never used after that point
and any even remotely sane compiler will manage to collapse that
into
	struct qstr x = {.name = s, .len = strlen(s)};

What compound literals can't be used for is initialization of
global variables, but those are covered by QSTR_INIT().

This commit lifts definition(s) of QSTR() into linux/dcache.h,
converts it to compound literal (all bcachefs users are fine
with that) and converts assorted open-coded instances to using
that.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2025-01-27 19:25:45 -05:00
..
dir.c kernfs: RCU protect kernfs_nodes and avoid kernfs_idr_lock in kernfs_find_and_get_node_by_id() 2024-01-30 15:54:25 -08:00
file.c add a string-to-qstr constructor 2025-01-27 19:25:45 -05:00
inode.c vfs-6.7.ctime 2023-10-30 09:47:13 -10:00
Kconfig
kernfs-internal.h kernfs: RCU protect kernfs_nodes and avoid kernfs_idr_lock in kernfs_find_and_get_node_by_id() 2024-01-30 15:54:25 -08:00
Makefile
mount.c kernfs: mount: Remove unnecessary ‘NULL’ values from knparent 2024-05-04 19:02:39 +02:00
symlink.c kernfs: fix all kernel-doc warnings and multiple typos 2022-11-23 19:28:26 +01:00