From: Christian Brauner <brauner@kernel.org>
To: Linus Torvalds <torvalds@linux-foundation.org>,
linux-fsdevel <linux-fsdevel@vger.kernel.org>
Cc: Christian Brauner <brauner@kernel.org>,
Mateusz Guzik <mjguzik@gmail.com>,
Al Viro <viro@zeniv.linux.org.uk>, Jan Kara <jack@suse.cz>,
Jeff Layton <jlayton@kernel.org>,
Josef Bacik <josef@toxicpanda.com>
Subject: [PATCH RFC 2/3] mnt_idmapping: add struct mnt_idmap to header
Date: Wed, 16 Apr 2025 15:17:23 +0200 [thread overview]
Message-ID: <20250416-work-mnt_idmap-s_user_ns-v1-2-273bef3a61ec@kernel.org> (raw)
In-Reply-To: <20250416-work-mnt_idmap-s_user_ns-v1-0-273bef3a61ec@kernel.org>
The next patch will inline all current helpers for that we need access
to struct mnt_idmap internals from the header. Not my favorite but
whatever.
Signed-off-by: Christian Brauner <brauner@kernel.org>
---
fs/mnt_idmapping.c | 6 ------
include/linux/mnt_idmapping.h | 7 +++++++
include/linux/uidgid.h | 23 ++++++++++++++++++++++-
include/linux/user_namespace.h | 23 +----------------------
4 files changed, 30 insertions(+), 29 deletions(-)
diff --git a/fs/mnt_idmapping.c b/fs/mnt_idmapping.c
index 8f7ae908ea16..5c7e1db8fef8 100644
--- a/fs/mnt_idmapping.c
+++ b/fs/mnt_idmapping.c
@@ -17,12 +17,6 @@
#define VFSUIDT_INIT_RAW(val) (vfsuid_t){ val }
#define VFSGIDT_INIT_RAW(val) (vfsgid_t){ val }
-struct mnt_idmap {
- struct uid_gid_map uid_map;
- struct uid_gid_map gid_map;
- refcount_t count;
-};
-
/*
* Carries the initial idmapping of 0:0:4294967295 which is an identity
* mapping. This means that {g,u}id 0 is mapped to {g,u}id 0, {g,u}id 1 is
diff --git a/include/linux/mnt_idmapping.h b/include/linux/mnt_idmapping.h
index 85553b3a7904..4410672c2828 100644
--- a/include/linux/mnt_idmapping.h
+++ b/include/linux/mnt_idmapping.h
@@ -8,6 +8,13 @@
struct mnt_idmap;
struct user_namespace;
+/* Don't touch directly! All fields private. */
+struct mnt_idmap {
+ struct uid_gid_map uid_map;
+ struct uid_gid_map gid_map;
+ refcount_t count;
+};
+
extern struct mnt_idmap nop_mnt_idmap;
extern struct mnt_idmap invalid_mnt_idmap;
extern struct user_namespace init_user_ns;
diff --git a/include/linux/uidgid.h b/include/linux/uidgid.h
index 2dc767e08f54..5696c870fd0b 100644
--- a/include/linux/uidgid.h
+++ b/include/linux/uidgid.h
@@ -17,7 +17,28 @@
struct user_namespace;
extern struct user_namespace init_user_ns;
-struct uid_gid_map;
+
+#define UID_GID_MAP_MAX_BASE_EXTENTS 5
+#define UID_GID_MAP_MAX_EXTENTS 340
+
+struct uid_gid_extent {
+ u32 first;
+ u32 lower_first;
+ u32 count;
+};
+
+struct uid_gid_map { /* 64 bytes -- 1 cache line */
+ union {
+ struct {
+ struct uid_gid_extent extent[UID_GID_MAP_MAX_BASE_EXTENTS];
+ u32 nr_extents;
+ };
+ struct {
+ struct uid_gid_extent *forward;
+ struct uid_gid_extent *reverse;
+ };
+ };
+};
#define KUIDT_INIT(value) (kuid_t){ value }
#define KGIDT_INIT(value) (kgid_t){ value }
diff --git a/include/linux/user_namespace.h b/include/linux/user_namespace.h
index a0bb6d012137..6feae94c3661 100644
--- a/include/linux/user_namespace.h
+++ b/include/linux/user_namespace.h
@@ -12,28 +12,7 @@
#include <linux/rwsem.h>
#include <linux/sysctl.h>
#include <linux/err.h>
-
-#define UID_GID_MAP_MAX_BASE_EXTENTS 5
-#define UID_GID_MAP_MAX_EXTENTS 340
-
-struct uid_gid_extent {
- u32 first;
- u32 lower_first;
- u32 count;
-};
-
-struct uid_gid_map { /* 64 bytes -- 1 cache line */
- union {
- struct {
- struct uid_gid_extent extent[UID_GID_MAP_MAX_BASE_EXTENTS];
- u32 nr_extents;
- };
- struct {
- struct uid_gid_extent *forward;
- struct uid_gid_extent *reverse;
- };
- };
-};
+#include <linux/uidgid.h>
#define USERNS_SETGROUPS_ALLOWED 1UL
--
2.47.2
next prev parent reply other threads:[~2025-04-16 13:17 UTC|newest]
Thread overview: 42+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-10-31 4:16 generic_permission() optimization Linus Torvalds
2024-10-31 6:05 ` Al Viro
2024-10-31 6:42 ` Linus Torvalds
2024-10-31 18:14 ` Linus Torvalds
2024-10-31 22:28 ` Al Viro
2024-10-31 22:34 ` Linus Torvalds
2024-11-01 1:17 ` Linus Torvalds
2024-11-01 1:27 ` Al Viro
2024-11-01 13:15 ` Christian Brauner
2024-10-31 13:02 ` Christian Brauner
2024-10-31 19:04 ` Linus Torvalds
2024-10-31 22:02 ` Linus Torvalds
2024-10-31 22:31 ` Linus Torvalds
2024-11-07 19:54 ` Linus Torvalds
2024-11-07 22:22 ` Mateusz Guzik
2024-11-07 22:49 ` Linus Torvalds
2025-04-12 16:26 ` Mateusz Guzik
2025-04-12 20:22 ` Linus Torvalds
2025-04-14 10:21 ` Christian Brauner
2025-04-16 13:17 ` [PATCH RFC 0/3] mnt_idmapping: avoid pointer chase & inline low-level helpers Christian Brauner
2025-04-16 13:17 ` [PATCH RFC 1/3] inode: add fastpath for filesystem user namespace retrieval Christian Brauner
2025-04-16 13:49 ` Mateusz Guzik
2025-04-16 14:14 ` Christian Brauner
2025-04-22 10:37 ` Jan Kara
2025-04-22 13:33 ` Mateusz Guzik
2025-04-22 14:05 ` Christian Brauner
2025-04-16 13:17 ` Christian Brauner [this message]
2025-04-16 13:17 ` [PATCH RFC 3/3] mnt_idmapping: inline all low-level helpers Christian Brauner
2025-04-16 15:04 ` Linus Torvalds
2025-04-22 9:28 ` Christian Brauner
2025-04-12 21:52 ` generic_permission() optimization Theodore Ts'o
2025-04-12 22:36 ` Linus Torvalds
2025-04-12 23:12 ` Linus Torvalds
2025-04-12 23:55 ` Theodore Ts'o
2025-04-13 9:41 ` Mateusz Guzik
2025-04-13 12:40 ` Theodore Ts'o
2025-04-13 12:52 ` Mateusz Guzik
2025-04-13 17:29 ` Theodore Ts'o
2025-11-05 11:50 ` Mateusz Guzik
2025-11-05 11:51 ` Mateusz Guzik
2025-11-05 13:37 ` Jan Kara
2025-11-17 11:42 ` Mateusz Guzik
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