adding OPEN_TREE_NAMESPACE and fsopen/fsconfig/fsmount/fspick constants for Linux (7.0)

#5072

[ref](https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/include/uapi/linux/mount.h?h=v7.0)

Author: devnexen

libc-test/build.rs

@@ -4201,6 +4201,14 @@ fn test_linux(target: &str) {
     cfg.skip_const(move |constant| {
         let name = constant.ident();
 
+        // FIXME(linux): Requires newer kernel headers than CI has. These uapi/linux/mount.h
+        // constants (OPEN_TREE_NAMESPACE landed in v7.0, FSCONFIG_CMD_CREATE_EXCL in v6.6)
+        // aren't defined by the headers CI builds against on several targets (notably the
+        // tier2 cross sysroots), so skip on every libc until CI catches up.
+        if name == "OPEN_TREE_NAMESPACE" || name == "FSCONFIG_CMD_CREATE_EXCL" {
+            return true;
+        }
+
         // L4Re requires a min stack size of 64k; that isn't defined in uClibc, but
         // somewhere in the core libraries. uClibc wants 16k, but that's not enough.
         if l4re && name == "PTHREAD_STACK_MIN" {
@@ -4223,6 +4231,10 @@ fn test_linux(target: &str) {
                 || name.starts_with("EPOLL")
                 || name.starts_with("F_")
                 || name.starts_with("FALLOC_FL_")
+                || name.starts_with("FSCONFIG_")
+                || name.starts_with("FSMOUNT_")
+                || name.starts_with("FSOPEN_")
+                || name.starts_with("FSPICK_")
                 || name.starts_with("FUTEX2_")
                 || name.starts_with("IFLA_")
                 || name.starts_with("KEXEC_")
@@ -4564,6 +4576,7 @@ fn test_linux(target: &str) {
 
     let c_enums = [
         "can_state",
+        "fsconfig_command",
         "membarrier_cmd",
         "pid_type",
         "proc_cn_event",

libc-test/semver/linux.txt

@@ -901,6 +901,21 @@ FIONCLEX
 FIONREAD
 FLUSHO
 FOPEN_MAX
+FSCONFIG_CMD_CREATE
+FSCONFIG_CMD_CREATE_EXCL
+FSCONFIG_CMD_RECONFIGURE
+FSCONFIG_SET_BINARY
+FSCONFIG_SET_FD
+FSCONFIG_SET_FLAG
+FSCONFIG_SET_PATH
+FSCONFIG_SET_PATH_EMPTY
+FSCONFIG_SET_STRING
+FSMOUNT_CLOEXEC
+FSOPEN_CLOEXEC
+FSPICK_CLOEXEC
+FSPICK_EMPTY_PATH
+FSPICK_NO_AUTOMOUNT
+FSPICK_SYMLINK_NOFOLLOW
 FS_IOC32_GETFLAGS
 FS_IOC32_GETVERSION
 FS_IOC32_SETFLAGS
@@ -2205,6 +2220,7 @@ OFILL
 OLCUC
 OPEN_TREE_CLOEXEC
 OPEN_TREE_CLONE
+OPEN_TREE_NAMESPACE
 O_ASYNC
 O_DIRECT
 O_DSYNC
@@ -4109,6 +4125,7 @@ freeifaddrs
 freelocale
 fremovexattr
 freopen64
+fsconfig_command
 fseeko64
 fsetpos64
 fsetxattr

src/unix/linux_like/linux/mod.rs

@@ -3106,8 +3106,32 @@ pub const IN_NONBLOCK: c_int = O_NONBLOCK;
 
 // uapi/linux/mount.h
 pub const OPEN_TREE_CLONE: c_uint = 0x01;
+pub const OPEN_TREE_NAMESPACE: c_uint = 0x02;
 pub const OPEN_TREE_CLOEXEC: c_uint = O_CLOEXEC as c_uint;
 
+pub const FSOPEN_CLOEXEC: c_uint = 0x00000001;
+
+pub const FSPICK_CLOEXEC: c_uint = 0x00000001;
+pub const FSPICK_SYMLINK_NOFOLLOW: c_uint = 0x00000002;
+pub const FSPICK_NO_AUTOMOUNT: c_uint = 0x00000004;
+pub const FSPICK_EMPTY_PATH: c_uint = 0x00000008;
+
+pub const FSMOUNT_CLOEXEC: c_uint = 0x00000001;
+
+c_enum! {
+    pub enum fsconfig_command {
+        pub FSCONFIG_SET_FLAG,
+        pub FSCONFIG_SET_STRING,
+        pub FSCONFIG_SET_BINARY,
+        pub FSCONFIG_SET_PATH,
+        pub FSCONFIG_SET_PATH_EMPTY,
+        pub FSCONFIG_SET_FD,
+        pub FSCONFIG_CMD_CREATE,
+        pub FSCONFIG_CMD_RECONFIGURE,
+        pub FSCONFIG_CMD_CREATE_EXCL,
+    }
+}
+
 // uapi/linux/netfilter/nf_tables.h
 pub const NFT_TABLE_MAXNAMELEN: c_int = 256;
 pub const NFT_CHAIN_MAXNAMELEN: c_int = 256;