linux: Add fsconfig

It was added on Linux 5.2 (ecdab150fddb42fe6a739335257949220033b782)
as a way to a configure filesystem creation context and trigger
actions upon it, to be used in conjunction with fsopen, fspick and
fsmount.

The fsconfig_command commands are currently only defined as an enum,
so they can't be checked on tst-mount-consts.py with current test
support.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>

NEWS

@@ -41,10 +41,10 @@ Major new features:
   have adverse impact.  It is incompatible with EDNS0 usage and DNSSEC
   validation by applications.
 
-* On Linux, the fsopen, fsmount, and move_mount functions have been added.
+* On Linux, the fsopen, fsmount, move_mount, and fsconfig functions have
-  They are part of the new Linux kernel mount APIs that allow applications
+  been added.  They are part of the new Linux kernel mount APIs that allow
-  to more flexibly configure and operate on filesystem mounts.  The new
+  applications to more flexibly configure and operate on filesystem mounts.
-  mount APIs are specifically designed to work with namespaces.
+  The new mount APIs are specifically designed to work with namespaces.
 
 * localedef now accepts locale definition files encoded in UTF-8.
   Previously, input bytes not within the ASCII range resulted in

sysdeps/unix/sysv/linux/Versions

@@ -300,6 +300,7 @@ libc {
     epoll_pwait2;
   }
   GLIBC_2.36 {
+    fsconfig;
     fsmount;
     fsopen;
     move_mount;

sysdeps/unix/sysv/linux/aarch64/libc.abilist

@@ -2616,6 +2616,7 @@ GLIBC_2.35 __memcmpeq F
 GLIBC_2.35 _dl_find_object F
 GLIBC_2.35 epoll_pwait2 F
 GLIBC_2.35 posix_spawn_file_actions_addtcsetpgrp_np F
+GLIBC_2.36 fsconfig F
 GLIBC_2.36 fsmount F
 GLIBC_2.36 fsopen F
 GLIBC_2.36 move_mount F

sysdeps/unix/sysv/linux/alpha/libc.abilist

@@ -2713,6 +2713,7 @@ GLIBC_2.35 __memcmpeq F
 GLIBC_2.35 _dl_find_object F
 GLIBC_2.35 epoll_pwait2 F
 GLIBC_2.35 posix_spawn_file_actions_addtcsetpgrp_np F
+GLIBC_2.36 fsconfig F
 GLIBC_2.36 fsmount F
 GLIBC_2.36 fsopen F
 GLIBC_2.36 move_mount F

sysdeps/unix/sysv/linux/arc/libc.abilist

@@ -2377,6 +2377,7 @@ GLIBC_2.35 __memcmpeq F
 GLIBC_2.35 _dl_find_object F
 GLIBC_2.35 epoll_pwait2 F
 GLIBC_2.35 posix_spawn_file_actions_addtcsetpgrp_np F
+GLIBC_2.36 fsconfig F
 GLIBC_2.36 fsmount F
 GLIBC_2.36 fsopen F
 GLIBC_2.36 move_mount F

sysdeps/unix/sysv/linux/arm/be/libc.abilist

@@ -496,6 +496,7 @@ GLIBC_2.35 __memcmpeq F
 GLIBC_2.35 _dl_find_object F
 GLIBC_2.35 epoll_pwait2 F
 GLIBC_2.35 posix_spawn_file_actions_addtcsetpgrp_np F
+GLIBC_2.36 fsconfig F
 GLIBC_2.36 fsmount F
 GLIBC_2.36 fsopen F
 GLIBC_2.36 move_mount F

sysdeps/unix/sysv/linux/arm/le/libc.abilist

@@ -493,6 +493,7 @@ GLIBC_2.35 __memcmpeq F
 GLIBC_2.35 _dl_find_object F
 GLIBC_2.35 epoll_pwait2 F
 GLIBC_2.35 posix_spawn_file_actions_addtcsetpgrp_np F
+GLIBC_2.36 fsconfig F
 GLIBC_2.36 fsmount F
 GLIBC_2.36 fsopen F
 GLIBC_2.36 move_mount F

sysdeps/unix/sysv/linux/csky/libc.abilist

@@ -2652,6 +2652,7 @@ GLIBC_2.35 __memcmpeq F
 GLIBC_2.35 _dl_find_object F
 GLIBC_2.35 epoll_pwait2 F
 GLIBC_2.35 posix_spawn_file_actions_addtcsetpgrp_np F
+GLIBC_2.36 fsconfig F
 GLIBC_2.36 fsmount F
 GLIBC_2.36 fsopen F
 GLIBC_2.36 move_mount F

sysdeps/unix/sysv/linux/hppa/libc.abilist

@@ -2601,6 +2601,7 @@ GLIBC_2.35 __memcmpeq F
 GLIBC_2.35 _dl_find_object F
 GLIBC_2.35 epoll_pwait2 F
 GLIBC_2.35 posix_spawn_file_actions_addtcsetpgrp_np F
+GLIBC_2.36 fsconfig F
 GLIBC_2.36 fsmount F
 GLIBC_2.36 fsopen F
 GLIBC_2.36 move_mount F

sysdeps/unix/sysv/linux/i386/libc.abilist

@@ -2785,6 +2785,7 @@ GLIBC_2.35 __memcmpeq F
 GLIBC_2.35 _dl_find_object F
 GLIBC_2.35 epoll_pwait2 F
 GLIBC_2.35 posix_spawn_file_actions_addtcsetpgrp_np F
+GLIBC_2.36 fsconfig F
 GLIBC_2.36 fsmount F
 GLIBC_2.36 fsopen F
 GLIBC_2.36 move_mount F

sysdeps/unix/sysv/linux/ia64/libc.abilist

@@ -2551,6 +2551,7 @@ GLIBC_2.35 __memcmpeq F
 GLIBC_2.35 _dl_find_object F
 GLIBC_2.35 epoll_pwait2 F
 GLIBC_2.35 posix_spawn_file_actions_addtcsetpgrp_np F
+GLIBC_2.36 fsconfig F
 GLIBC_2.36 fsmount F
 GLIBC_2.36 fsopen F
 GLIBC_2.36 move_mount F

sysdeps/unix/sysv/linux/m68k/coldfire/libc.abilist

@@ -497,6 +497,7 @@ GLIBC_2.35 __memcmpeq F
 GLIBC_2.35 _dl_find_object F
 GLIBC_2.35 epoll_pwait2 F
 GLIBC_2.35 posix_spawn_file_actions_addtcsetpgrp_np F
+GLIBC_2.36 fsconfig F
 GLIBC_2.36 fsmount F
 GLIBC_2.36 fsopen F
 GLIBC_2.36 move_mount F

sysdeps/unix/sysv/linux/m68k/m680x0/libc.abilist

@@ -2728,6 +2728,7 @@ GLIBC_2.35 __memcmpeq F
 GLIBC_2.35 _dl_find_object F
 GLIBC_2.35 epoll_pwait2 F
 GLIBC_2.35 posix_spawn_file_actions_addtcsetpgrp_np F
+GLIBC_2.36 fsconfig F
 GLIBC_2.36 fsmount F
 GLIBC_2.36 fsopen F
 GLIBC_2.36 move_mount F

sysdeps/unix/sysv/linux/microblaze/be/libc.abilist

@@ -2701,6 +2701,7 @@ GLIBC_2.35 __memcmpeq F
 GLIBC_2.35 _dl_find_object F
 GLIBC_2.35 epoll_pwait2 F
 GLIBC_2.35 posix_spawn_file_actions_addtcsetpgrp_np F
+GLIBC_2.36 fsconfig F
 GLIBC_2.36 fsmount F
 GLIBC_2.36 fsopen F
 GLIBC_2.36 move_mount F

sysdeps/unix/sysv/linux/microblaze/le/libc.abilist

@@ -2698,6 +2698,7 @@ GLIBC_2.35 __memcmpeq F
 GLIBC_2.35 _dl_find_object F
 GLIBC_2.35 epoll_pwait2 F
 GLIBC_2.35 posix_spawn_file_actions_addtcsetpgrp_np F
+GLIBC_2.36 fsconfig F
 GLIBC_2.36 fsmount F
 GLIBC_2.36 fsopen F
 GLIBC_2.36 move_mount F

sysdeps/unix/sysv/linux/mips/mips32/fpu/libc.abilist

@@ -2693,6 +2693,7 @@ GLIBC_2.35 __memcmpeq F
 GLIBC_2.35 _dl_find_object F
 GLIBC_2.35 epoll_pwait2 F
 GLIBC_2.35 posix_spawn_file_actions_addtcsetpgrp_np F
+GLIBC_2.36 fsconfig F
 GLIBC_2.36 fsmount F
 GLIBC_2.36 fsopen F
 GLIBC_2.36 move_mount F

sysdeps/unix/sysv/linux/mips/mips32/nofpu/libc.abilist

@@ -2691,6 +2691,7 @@ GLIBC_2.35 __memcmpeq F
 GLIBC_2.35 _dl_find_object F
 GLIBC_2.35 epoll_pwait2 F
 GLIBC_2.35 posix_spawn_file_actions_addtcsetpgrp_np F
+GLIBC_2.36 fsconfig F
 GLIBC_2.36 fsmount F
 GLIBC_2.36 fsopen F
 GLIBC_2.36 move_mount F

sysdeps/unix/sysv/linux/mips/mips64/n32/libc.abilist

@@ -2699,6 +2699,7 @@ GLIBC_2.35 __memcmpeq F
 GLIBC_2.35 _dl_find_object F
 GLIBC_2.35 epoll_pwait2 F
 GLIBC_2.35 posix_spawn_file_actions_addtcsetpgrp_np F
+GLIBC_2.36 fsconfig F
 GLIBC_2.36 fsmount F
 GLIBC_2.36 fsopen F
 GLIBC_2.36 move_mount F

sysdeps/unix/sysv/linux/mips/mips64/n64/libc.abilist

@@ -2602,6 +2602,7 @@ GLIBC_2.35 __memcmpeq F
 GLIBC_2.35 _dl_find_object F
 GLIBC_2.35 epoll_pwait2 F
 GLIBC_2.35 posix_spawn_file_actions_addtcsetpgrp_np F
+GLIBC_2.36 fsconfig F
 GLIBC_2.36 fsmount F
 GLIBC_2.36 fsopen F
 GLIBC_2.36 move_mount F

sysdeps/unix/sysv/linux/nios2/libc.abilist

@@ -2740,6 +2740,7 @@ GLIBC_2.35 __memcmpeq F
 GLIBC_2.35 _dl_find_object F
 GLIBC_2.35 epoll_pwait2 F
 GLIBC_2.35 posix_spawn_file_actions_addtcsetpgrp_np F
+GLIBC_2.36 fsconfig F
 GLIBC_2.36 fsmount F
 GLIBC_2.36 fsopen F
 GLIBC_2.36 move_mount F

sysdeps/unix/sysv/linux/or1k/libc.abilist

@@ -2123,6 +2123,7 @@ GLIBC_2.35 wprintf F
 GLIBC_2.35 write F
 GLIBC_2.35 writev F
 GLIBC_2.35 wscanf F
+GLIBC_2.36 fsconfig F
 GLIBC_2.36 fsmount F
 GLIBC_2.36 fsopen F
 GLIBC_2.36 move_mount F

sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/libc.abilist

@@ -2755,6 +2755,7 @@ GLIBC_2.35 __memcmpeq F
 GLIBC_2.35 _dl_find_object F
 GLIBC_2.35 epoll_pwait2 F
 GLIBC_2.35 posix_spawn_file_actions_addtcsetpgrp_np F
+GLIBC_2.36 fsconfig F
 GLIBC_2.36 fsmount F
 GLIBC_2.36 fsopen F
 GLIBC_2.36 move_mount F

sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/libc.abilist

@@ -2788,6 +2788,7 @@ GLIBC_2.35 __memcmpeq F
 GLIBC_2.35 _dl_find_object F
 GLIBC_2.35 epoll_pwait2 F
 GLIBC_2.35 posix_spawn_file_actions_addtcsetpgrp_np F
+GLIBC_2.36 fsconfig F
 GLIBC_2.36 fsmount F
 GLIBC_2.36 fsopen F
 GLIBC_2.36 move_mount F

sysdeps/unix/sysv/linux/powerpc/powerpc64/be/libc.abilist

@@ -2510,6 +2510,7 @@ GLIBC_2.35 __memcmpeq F
 GLIBC_2.35 _dl_find_object F
 GLIBC_2.35 epoll_pwait2 F
 GLIBC_2.35 posix_spawn_file_actions_addtcsetpgrp_np F
+GLIBC_2.36 fsconfig F
 GLIBC_2.36 fsmount F
 GLIBC_2.36 fsopen F
 GLIBC_2.36 move_mount F

sysdeps/unix/sysv/linux/powerpc/powerpc64/le/libc.abilist

@@ -2812,6 +2812,7 @@ GLIBC_2.35 __memcmpeq F
 GLIBC_2.35 _dl_find_object F
 GLIBC_2.35 epoll_pwait2 F
 GLIBC_2.35 posix_spawn_file_actions_addtcsetpgrp_np F
+GLIBC_2.36 fsconfig F
 GLIBC_2.36 fsmount F
 GLIBC_2.36 fsopen F
 GLIBC_2.36 move_mount F

sysdeps/unix/sysv/linux/riscv/rv32/libc.abilist

@@ -2379,6 +2379,7 @@ GLIBC_2.35 __memcmpeq F
 GLIBC_2.35 _dl_find_object F
 GLIBC_2.35 epoll_pwait2 F
 GLIBC_2.35 posix_spawn_file_actions_addtcsetpgrp_np F
+GLIBC_2.36 fsconfig F
 GLIBC_2.36 fsmount F
 GLIBC_2.36 fsopen F
 GLIBC_2.36 move_mount F

sysdeps/unix/sysv/linux/riscv/rv64/libc.abilist

@@ -2579,6 +2579,7 @@ GLIBC_2.35 __memcmpeq F
 GLIBC_2.35 _dl_find_object F
 GLIBC_2.35 epoll_pwait2 F
 GLIBC_2.35 posix_spawn_file_actions_addtcsetpgrp_np F
+GLIBC_2.36 fsconfig F
 GLIBC_2.36 fsmount F
 GLIBC_2.36 fsopen F
 GLIBC_2.36 move_mount F

sysdeps/unix/sysv/linux/s390/s390-32/libc.abilist

@@ -2753,6 +2753,7 @@ GLIBC_2.35 __memcmpeq F
 GLIBC_2.35 _dl_find_object F
 GLIBC_2.35 epoll_pwait2 F
 GLIBC_2.35 posix_spawn_file_actions_addtcsetpgrp_np F
+GLIBC_2.36 fsconfig F
 GLIBC_2.36 fsmount F
 GLIBC_2.36 fsopen F
 GLIBC_2.36 move_mount F

sysdeps/unix/sysv/linux/s390/s390-64/libc.abilist

@@ -2547,6 +2547,7 @@ GLIBC_2.35 __memcmpeq F
 GLIBC_2.35 _dl_find_object F
 GLIBC_2.35 epoll_pwait2 F
 GLIBC_2.35 posix_spawn_file_actions_addtcsetpgrp_np F
+GLIBC_2.36 fsconfig F
 GLIBC_2.36 fsmount F
 GLIBC_2.36 fsopen F
 GLIBC_2.36 move_mount F

sysdeps/unix/sysv/linux/sh/be/libc.abilist

@@ -2608,6 +2608,7 @@ GLIBC_2.35 __memcmpeq F
 GLIBC_2.35 _dl_find_object F
 GLIBC_2.35 epoll_pwait2 F
 GLIBC_2.35 posix_spawn_file_actions_addtcsetpgrp_np F
+GLIBC_2.36 fsconfig F
 GLIBC_2.36 fsmount F
 GLIBC_2.36 fsopen F
 GLIBC_2.36 move_mount F

sysdeps/unix/sysv/linux/sh/le/libc.abilist

@@ -2605,6 +2605,7 @@ GLIBC_2.35 __memcmpeq F
 GLIBC_2.35 _dl_find_object F
 GLIBC_2.35 epoll_pwait2 F
 GLIBC_2.35 posix_spawn_file_actions_addtcsetpgrp_np F
+GLIBC_2.36 fsconfig F
 GLIBC_2.36 fsmount F
 GLIBC_2.36 fsopen F
 GLIBC_2.36 move_mount F

sysdeps/unix/sysv/linux/sparc/sparc32/libc.abilist

@@ -2748,6 +2748,7 @@ GLIBC_2.35 __memcmpeq F
 GLIBC_2.35 _dl_find_object F
 GLIBC_2.35 epoll_pwait2 F
 GLIBC_2.35 posix_spawn_file_actions_addtcsetpgrp_np F
+GLIBC_2.36 fsconfig F
 GLIBC_2.36 fsmount F
 GLIBC_2.36 fsopen F
 GLIBC_2.36 move_mount F

sysdeps/unix/sysv/linux/sparc/sparc64/libc.abilist

@@ -2574,6 +2574,7 @@ GLIBC_2.35 __memcmpeq F
 GLIBC_2.35 _dl_find_object F
 GLIBC_2.35 epoll_pwait2 F
 GLIBC_2.35 posix_spawn_file_actions_addtcsetpgrp_np F
+GLIBC_2.36 fsconfig F
 GLIBC_2.36 fsmount F
 GLIBC_2.36 fsopen F
 GLIBC_2.36 move_mount F

sysdeps/unix/sysv/linux/sys/mount.h

@@ -163,6 +163,27 @@ enum
 #define MOVE_MOUNT_T_EMPTY_PATH 0x00000040 /* Empty to path permitted */
 #define MOVE_MOUNT_SET_GROUP    0x00000100 /* Set sharing group instead */
 
+/* The type of fsconfig call made.   */
+enum fsconfig_command
+{
+  FSCONFIG_SET_FLAG       = 0,    /* Set parameter, supplying no value */
+#define FSCONFIG_SET_FLAG FSCONFIG_SET_FLAG
+  FSCONFIG_SET_STRING     = 1,    /* Set parameter, supplying a string value */
+#define FSCONFIG_SET_STRING FSCONFIG_SET_STRING
+  FSCONFIG_SET_BINARY     = 2,    /* Set parameter, supplying a binary blob value */
+#define FSCONFIG_SET_BINARY FSCONFIG_SET_BINARY
+  FSCONFIG_SET_PATH       = 3,    /* Set parameter, supplying an object by path */
+#define FSCONFIG_SET_PATH FSCONFIG_SET_PATH
+  FSCONFIG_SET_PATH_EMPTY = 4,    /* Set parameter, supplying an object by (empty) path */
+#define FSCONFIG_SET_PATH_EMPTY FSCONFIG_SET_PATH_EMPTY
+  FSCONFIG_SET_FD         = 5,    /* Set parameter, supplying an object by fd */
+#define FSCONFIG_SET_FD FSCONFIG_SET_FD
+  FSCONFIG_CMD_CREATE     = 6,    /* Invoke superblock creation */
+#define FSCONFIG_CMD_CREATE FSCONFIG_CMD_CREATE
+  FSCONFIG_CMD_RECONFIGURE = 7,   /* Invoke superblock reconfiguration */
+#define FSCONFIG_CMD_RECONFIGURE FSCONFIG_CMD_RECONFIGURE
+};
+
 
 __BEGIN_DECLS
 
@@ -193,6 +214,11 @@ extern int move_mount (int __from_dfd, const char *__from_pathname,
 		       int __to_dfd, const char *__to_pathname,
 		       unsigned int flags) __THROW;
 
+/* Set parameters and trigger CMD action on the FD context.  KEY, VALUE,
+   and AUX are used depending ng of the CMD.  */
+extern int fsconfig (int __fd, unsigned int __cmd, const char *__key,
+		     const void *__value, int __aux) __THROW;
+
 __END_DECLS
 
 #endif /* _SYS_MOUNT_H */

sysdeps/unix/sysv/linux/syscalls.list

@@ -12,6 +12,7 @@ epoll_ctl	EXTRA	epoll_ctl	i:iiip	epoll_ctl
 eventfd		EXTRA	eventfd2	i:ii	eventfd
 execve		-	execve		i:spp	__execve	execve
 flock		-	flock		i:ii	__flock		flock
+fsconfig	EXTRA	fsconfig	i:iUsNi	fsconfig
 fsmount		EXTRA	fsmount		i:iUU	fsmount
 fsopen		EXTRA	fsopen		i:sU	fsopen
 get_kernel_syms	EXTRA	get_kernel_syms	i:p	__compat_get_kernel_syms	get_kernel_syms@GLIBC_2.0:GLIBC_2.23

sysdeps/unix/sysv/linux/tst-mount-consts.py

@@ -49,6 +49,8 @@ def main():
                 linux_version_glibc > linux_version_headers,
                 linux_version_headers > linux_version_glibc)
 
+    # Skip testing FS_CONFIG commands since they are only enums in the kernel
+    # header.
     status = max(
         check('FSOPEN_.*'),
         check('FSMOUNT_.*'),

sysdeps/unix/sysv/linux/x86_64/64/libc.abilist

@@ -2525,6 +2525,7 @@ GLIBC_2.35 __memcmpeq F
 GLIBC_2.35 _dl_find_object F
 GLIBC_2.35 epoll_pwait2 F
 GLIBC_2.35 posix_spawn_file_actions_addtcsetpgrp_np F
+GLIBC_2.36 fsconfig F
 GLIBC_2.36 fsmount F
 GLIBC_2.36 fsopen F
 GLIBC_2.36 move_mount F

sysdeps/unix/sysv/linux/x86_64/x32/libc.abilist

@@ -2631,6 +2631,7 @@ GLIBC_2.35 __memcmpeq F
 GLIBC_2.35 _dl_find_object F
 GLIBC_2.35 epoll_pwait2 F
 GLIBC_2.35 posix_spawn_file_actions_addtcsetpgrp_np F
+GLIBC_2.36 fsconfig F
 GLIBC_2.36 fsmount F
 GLIBC_2.36 fsopen F
 GLIBC_2.36 move_mount F