[PATCH v5 13/14] epoll: implement epoll_create2() syscall

From: Roman Penyaev
Date: Mon Jun 24 2019 - 10:42:32 EST


epoll_create2() is needed to accept EPOLL_USERPOLL flags
and size, i.e. this patch wires up polling from userspace.

Signed-off-by: Roman Penyaev <rpenyaev@xxxxxxx>
Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Cc: Al Viro <viro@xxxxxxxxxxxxxxxxxx>
Cc: Arnd Bergmann <arnd@xxxxxxxx>
Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Cc: linux-fsdevel@xxxxxxxxxxxxxxx
Cc: linux-kernel@xxxxxxxxxxxxxxx
---
arch/alpha/kernel/syscalls/syscall.tbl | 2 ++
arch/arm/tools/syscall.tbl | 1 +
arch/arm64/include/asm/unistd.h | 2 +-
arch/arm64/include/asm/unistd32.h | 2 ++
arch/ia64/kernel/syscalls/syscall.tbl | 2 ++
arch/m68k/kernel/syscalls/syscall.tbl | 2 ++
arch/microblaze/kernel/syscalls/syscall.tbl | 1 +
arch/mips/kernel/syscalls/syscall_n32.tbl | 2 ++
arch/mips/kernel/syscalls/syscall_n64.tbl | 2 ++
arch/mips/kernel/syscalls/syscall_o32.tbl | 2 ++
arch/parisc/kernel/syscalls/syscall.tbl | 2 ++
arch/powerpc/kernel/syscalls/syscall.tbl | 2 ++
arch/s390/kernel/syscalls/syscall.tbl | 2 ++
arch/sh/kernel/syscalls/syscall.tbl | 2 ++
arch/sparc/kernel/syscalls/syscall.tbl | 2 ++
arch/x86/entry/syscalls/syscall_32.tbl | 1 +
arch/x86/entry/syscalls/syscall_64.tbl | 1 +
arch/xtensa/kernel/syscalls/syscall.tbl | 1 +
fs/eventpoll.c | 5 +++++
include/linux/syscalls.h | 1 +
include/uapi/asm-generic/unistd.h | 4 +++-
kernel/sys_ni.c | 1 +
22 files changed, 40 insertions(+), 2 deletions(-)

diff --git a/arch/alpha/kernel/syscalls/syscall.tbl b/arch/alpha/kernel/syscalls/syscall.tbl
index 1db9bbcfb84e..a1d7b695063d 100644
--- a/arch/alpha/kernel/syscalls/syscall.tbl
+++ b/arch/alpha/kernel/syscalls/syscall.tbl
@@ -474,3 +474,5 @@
542 common fsmount sys_fsmount
543 common fspick sys_fspick
544 common pidfd_open sys_pidfd_open
+# 546 common clone3 sys_clone3
+547 common epoll_create2 sys_epoll_create2
diff --git a/arch/arm/tools/syscall.tbl b/arch/arm/tools/syscall.tbl
index ff45d8807cb8..1497f3c87d54 100644
--- a/arch/arm/tools/syscall.tbl
+++ b/arch/arm/tools/syscall.tbl
@@ -449,3 +449,4 @@
433 common fspick sys_fspick
434 common pidfd_open sys_pidfd_open
436 common clone3 sys_clone3
+437 common epoll_create2 sys_epoll_create2
diff --git a/arch/arm64/include/asm/unistd.h b/arch/arm64/include/asm/unistd.h
index e4e0523102e2..7fb8d77e2340 100644
--- a/arch/arm64/include/asm/unistd.h
+++ b/arch/arm64/include/asm/unistd.h
@@ -44,7 +44,7 @@
#define __ARM_NR_compat_set_tls (__ARM_NR_COMPAT_BASE + 5)
#define __ARM_NR_COMPAT_END (__ARM_NR_COMPAT_BASE + 0x800)

-#define __NR_compat_syscalls 437
+#define __NR_compat_syscalls 438
#endif

#define __ARCH_WANT_SYS_CLONE
diff --git a/arch/arm64/include/asm/unistd32.h b/arch/arm64/include/asm/unistd32.h
index 10f16b0175ca..eb467e639352 100644
--- a/arch/arm64/include/asm/unistd32.h
+++ b/arch/arm64/include/asm/unistd32.h
@@ -890,6 +890,8 @@ __SYSCALL(__NR_fspick, sys_fspick)
__SYSCALL(__NR_pidfd_open, sys_pidfd_open)
#define __NR_clone3 436
__SYSCALL(__NR_clone3, sys_clone3)
+#define __NR_epoll_create2 437
+__SYSCALL(__NR_epoll_create2, sys_epoll_create2)

/*
* Please add new compat syscalls above this comment and update
diff --git a/arch/ia64/kernel/syscalls/syscall.tbl b/arch/ia64/kernel/syscalls/syscall.tbl
index ecc44926737b..5cecff901853 100644
--- a/arch/ia64/kernel/syscalls/syscall.tbl
+++ b/arch/ia64/kernel/syscalls/syscall.tbl
@@ -355,3 +355,5 @@
432 common fsmount sys_fsmount
433 common fspick sys_fspick
434 common pidfd_open sys_pidfd_open
+# 436 common clone3 sys_clone3
+437 common epoll_create2 sys_epoll_create2
diff --git a/arch/m68k/kernel/syscalls/syscall.tbl b/arch/m68k/kernel/syscalls/syscall.tbl
index 9a3eb2558568..29d944e2e9d6 100644
--- a/arch/m68k/kernel/syscalls/syscall.tbl
+++ b/arch/m68k/kernel/syscalls/syscall.tbl
@@ -434,3 +434,5 @@
432 common fsmount sys_fsmount
433 common fspick sys_fspick
434 common pidfd_open sys_pidfd_open
+# 436 common clone3 sys_clone3
+437 common epoll_create2 sys_epoll_create2
diff --git a/arch/microblaze/kernel/syscalls/syscall.tbl b/arch/microblaze/kernel/syscalls/syscall.tbl
index 9181f181f76d..fad83841b16b 100644
--- a/arch/microblaze/kernel/syscalls/syscall.tbl
+++ b/arch/microblaze/kernel/syscalls/syscall.tbl
@@ -441,3 +441,4 @@
433 common fspick sys_fspick
434 common pidfd_open sys_pidfd_open
436 common clone3 sys_clone3
+437 common epoll_create2 sys_epoll_create2
diff --git a/arch/mips/kernel/syscalls/syscall_n32.tbl b/arch/mips/kernel/syscalls/syscall_n32.tbl
index 97035e19ad03..661d63d7ea84 100644
--- a/arch/mips/kernel/syscalls/syscall_n32.tbl
+++ b/arch/mips/kernel/syscalls/syscall_n32.tbl
@@ -373,3 +373,5 @@
432 n32 fsmount sys_fsmount
433 n32 fspick sys_fspick
434 n32 pidfd_open sys_pidfd_open
+# 436 n32 clone3 sys_clone3
+437 n32 epoll_create2 sys_epoll_create2
diff --git a/arch/mips/kernel/syscalls/syscall_n64.tbl b/arch/mips/kernel/syscalls/syscall_n64.tbl
index d7292722d3b0..4a7f270ef126 100644
--- a/arch/mips/kernel/syscalls/syscall_n64.tbl
+++ b/arch/mips/kernel/syscalls/syscall_n64.tbl
@@ -349,3 +349,5 @@
432 n64 fsmount sys_fsmount
433 n64 fspick sys_fspick
434 n64 pidfd_open sys_pidfd_open
+# 436 n64 clone3 sys_clone3
+437 n64 epoll_create2 sys_epoll_create2
diff --git a/arch/mips/kernel/syscalls/syscall_o32.tbl b/arch/mips/kernel/syscalls/syscall_o32.tbl
index dba084c92f14..db87225a9dc5 100644
--- a/arch/mips/kernel/syscalls/syscall_o32.tbl
+++ b/arch/mips/kernel/syscalls/syscall_o32.tbl
@@ -422,3 +422,5 @@
432 o32 fsmount sys_fsmount
433 o32 fspick sys_fspick
434 o32 pidfd_open sys_pidfd_open
+# 436 o32 clone3 sys_clone3
+437 o32 epoll_create2 sys_epoll_create2
diff --git a/arch/parisc/kernel/syscalls/syscall.tbl b/arch/parisc/kernel/syscalls/syscall.tbl
index 5022b9e179c2..25374a2c4e16 100644
--- a/arch/parisc/kernel/syscalls/syscall.tbl
+++ b/arch/parisc/kernel/syscalls/syscall.tbl
@@ -431,3 +431,5 @@
432 common fsmount sys_fsmount
433 common fspick sys_fspick
434 common pidfd_open sys_pidfd_open
+# 436 common clone3 sys_clone3
+437 common epoll_create2 sys_epoll_create2
diff --git a/arch/powerpc/kernel/syscalls/syscall.tbl b/arch/powerpc/kernel/syscalls/syscall.tbl
index f2c3bda2d39f..9f48d8a737ab 100644
--- a/arch/powerpc/kernel/syscalls/syscall.tbl
+++ b/arch/powerpc/kernel/syscalls/syscall.tbl
@@ -516,3 +516,5 @@
432 common fsmount sys_fsmount
433 common fspick sys_fspick
434 common pidfd_open sys_pidfd_open
+# 436 common clone3 sys_clone3
+437 common epoll_create2 sys_epoll_create2
diff --git a/arch/s390/kernel/syscalls/syscall.tbl b/arch/s390/kernel/syscalls/syscall.tbl
index 6ebacfeaf853..0cef54850a1c 100644
--- a/arch/s390/kernel/syscalls/syscall.tbl
+++ b/arch/s390/kernel/syscalls/syscall.tbl
@@ -437,3 +437,5 @@
432 common fsmount sys_fsmount sys_fsmount
433 common fspick sys_fspick sys_fspick
434 common pidfd_open sys_pidfd_open sys_pidfd_open
+# 436 common clone3 sys_clone3 sys_clone3
+437 common epoll_create2 sys_epoll_create2 sys_epoll_create2
diff --git a/arch/sh/kernel/syscalls/syscall.tbl b/arch/sh/kernel/syscalls/syscall.tbl
index 834c9c7d79fa..42769d6ec8fe 100644
--- a/arch/sh/kernel/syscalls/syscall.tbl
+++ b/arch/sh/kernel/syscalls/syscall.tbl
@@ -437,3 +437,5 @@
432 common fsmount sys_fsmount
433 common fspick sys_fspick
434 common pidfd_open sys_pidfd_open
+# 436 common clone3 sys_clone3
+437 common epoll_create2 sys_epoll_create2
diff --git a/arch/sparc/kernel/syscalls/syscall.tbl b/arch/sparc/kernel/syscalls/syscall.tbl
index c58e71f21129..bf86fa32913d 100644
--- a/arch/sparc/kernel/syscalls/syscall.tbl
+++ b/arch/sparc/kernel/syscalls/syscall.tbl
@@ -480,3 +480,5 @@
432 common fsmount sys_fsmount
433 common fspick sys_fspick
434 common pidfd_open sys_pidfd_open
+# 436 common clone3 sys_clone3
+437 common epoll_create2 sys_epoll_create2
diff --git a/arch/x86/entry/syscalls/syscall_32.tbl b/arch/x86/entry/syscalls/syscall_32.tbl
index 6a99dbbf7e04..26d64f09b097 100644
--- a/arch/x86/entry/syscalls/syscall_32.tbl
+++ b/arch/x86/entry/syscalls/syscall_32.tbl
@@ -440,3 +440,4 @@
433 i386 fspick sys_fspick __ia32_sys_fspick
434 i386 pidfd_open sys_pidfd_open __ia32_sys_pidfd_open
436 i386 clone3 sys_clone3 __ia32_sys_clone3
+437 i386 epoll_create2 sys_epoll_create2 __ia32_sys_epoll_create2
diff --git a/arch/x86/entry/syscalls/syscall_64.tbl b/arch/x86/entry/syscalls/syscall_64.tbl
index 68227c7f71e5..4b58d8694693 100644
--- a/arch/x86/entry/syscalls/syscall_64.tbl
+++ b/arch/x86/entry/syscalls/syscall_64.tbl
@@ -357,6 +357,7 @@
433 common fspick __x64_sys_fspick
434 common pidfd_open __x64_sys_pidfd_open
436 common clone3 __x64_sys_clone3/ptregs
+437 common epoll_create2 __x64_sys_epoll_create2

#
# x32-specific system call numbers start at 512 to avoid cache impact
diff --git a/arch/xtensa/kernel/syscalls/syscall.tbl b/arch/xtensa/kernel/syscalls/syscall.tbl
index d5a1fd2c96c7..eef4367d433e 100644
--- a/arch/xtensa/kernel/syscalls/syscall.tbl
+++ b/arch/xtensa/kernel/syscalls/syscall.tbl
@@ -406,3 +406,4 @@
433 common fspick sys_fspick
434 common pidfd_open sys_pidfd_open
436 common clone3 sys_clone3
+437 common epoll_create2 sys_epoll_create2
diff --git a/fs/eventpoll.c b/fs/eventpoll.c
index 34239564bdfb..c3379bb4209b 100644
--- a/fs/eventpoll.c
+++ b/fs/eventpoll.c
@@ -2825,6 +2825,11 @@ static int do_epoll_create(int flags, size_t size)
return error;
}

+SYSCALL_DEFINE2(epoll_create2, int, flags, size_t, size)
+{
+ return do_epoll_create(flags, size);
+}
+
SYSCALL_DEFINE1(epoll_create1, int, flags)
{
return do_epoll_create(flags, 0);
diff --git a/include/linux/syscalls.h b/include/linux/syscalls.h
index b01d54a5732e..655ac0ebfdf9 100644
--- a/include/linux/syscalls.h
+++ b/include/linux/syscalls.h
@@ -357,6 +357,7 @@ asmlinkage long sys_eventfd2(unsigned int count, int flags);

/* fs/eventpoll.c */
asmlinkage long sys_epoll_create1(int flags);
+asmlinkage long sys_epoll_create2(int flags, size_t size);
asmlinkage long sys_epoll_ctl(int epfd, int op, int fd,
struct epoll_event __user *event);
asmlinkage long sys_epoll_pwait(int epfd, struct epoll_event __user *events,
diff --git a/include/uapi/asm-generic/unistd.h b/include/uapi/asm-generic/unistd.h
index 7c7c14a2e097..59c9dea64565 100644
--- a/include/uapi/asm-generic/unistd.h
+++ b/include/uapi/asm-generic/unistd.h
@@ -848,9 +848,11 @@ __SYSCALL(__NR_fspick, sys_fspick)
__SYSCALL(__NR_pidfd_open, sys_pidfd_open)
#define __NR_clone3 436
__SYSCALL(__NR_clone3, sys_clone3)
+#define __NR_epoll_create2 437
+__SYSCALL(__NR_epoll_create2, sys_epoll_create2)

#undef __NR_syscalls
-#define __NR_syscalls 437
+#define __NR_syscalls 438

/*
* 32 bit systems traditionally used different
diff --git a/kernel/sys_ni.c b/kernel/sys_ni.c
index 34b76895b81e..090ff3aa7568 100644
--- a/kernel/sys_ni.c
+++ b/kernel/sys_ni.c
@@ -65,6 +65,7 @@ COND_SYSCALL(eventfd2);

/* fs/eventfd.c */
COND_SYSCALL(epoll_create1);
+COND_SYSCALL(epoll_create2);
COND_SYSCALL(epoll_ctl);
COND_SYSCALL(epoll_pwait);
COND_SYSCALL_COMPAT(epoll_pwait);
--
2.21.0