[PATCH v9 2/6] mm: mlock: Add new mlock system call
From: Eric B Munson <hidden>
Date: 2015-09-08 13:59:19
Also in:
linux-alpha, linux-arch, linux-arm-kernel, linux-m68k, linux-mm, linux-s390, linux-sh, linuxppc-dev, lkml, sparclinux
Subsystem:
abi/api, generic include/asm header files, memory management, memory mapping, the rest, x86 architecture (32-bit and 64-bit), x86 entry code · Maintainers:
Arnd Bergmann, Andrew Morton, Liam R. Howlett, Lorenzo Stoakes, Linus Torvalds, Thomas Gleixner, Ingo Molnar, Borislav Petkov, Dave Hansen, Andy Lutomirski
With the refactored mlock code, introduce a new system call for mlock. The new call will allow the user to specify what lock states are being added. mlock2 is trivial at the moment, but a follow on patch will add a new mlock state making it useful. Signed-off-by: Eric B Munson <redacted> Acked-by: Vlastimil Babka <redacted> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Michal Hocko <redacted> Cc: Vlastimil Babka <redacted> Cc: Heiko Carstens <redacted> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Stephen Rothwell <redacted> Cc: Guenter Roeck <linux@roeck-us.net> Cc: linux-alpha@vger.kernel.org Cc: linux-kernel@vger.kernel.org Cc: linux-arm-kernel@lists.infradead.org Cc: adi-buildroot-devel@lists.sourceforge.net Cc: linux-cris-kernel@axis.com Cc: linux-ia64@vger.kernel.org Cc: linux-m68k@lists.linux-m68k.org Cc: linux-am33-list@redhat.com Cc: linux-parisc@vger.kernel.org Cc: linuxppc-dev@lists.ozlabs.org Cc: linux-s390@vger.kernel.org Cc: linux-sh@vger.kernel.org Cc: sparclinux@vger.kernel.org Cc: linux-xtensa@linux-xtensa.org Cc: linux-api@vger.kernel.org Cc: linux-arch@vger.kernel.org Cc: linux-mm@kvack.org --- Changes from V8: * Update x86[_64] syscall numbers to follow the new userfaultfd syscalls arch/x86/entry/syscalls/syscall_32.tbl | 1 + arch/x86/entry/syscalls/syscall_64.tbl | 1 + include/linux/syscalls.h | 2 ++ include/uapi/asm-generic/unistd.h | 4 +++- kernel/sys_ni.c | 1 + mm/mlock.c | 8 ++++++++ 6 files changed, 16 insertions(+), 1 deletion(-)
diff --git a/arch/x86/entry/syscalls/syscall_32.tbl b/arch/x86/entry/syscalls/syscall_32.tbl
index 477bfa6..41e72a5 100644
--- a/arch/x86/entry/syscalls/syscall_32.tbl
+++ b/arch/x86/entry/syscalls/syscall_32.tbl@@ -381,3 +381,4 @@ 372 i386 recvmsg sys_recvmsg compat_sys_recvmsg 373 i386 shutdown sys_shutdown 374 i386 userfaultfd sys_userfaultfd +375 i386 mlock2 sys_mlock2
diff --git a/arch/x86/entry/syscalls/syscall_64.tbl b/arch/x86/entry/syscalls/syscall_64.tbl
index 81c4906..2366900 100644
--- a/arch/x86/entry/syscalls/syscall_64.tbl
+++ b/arch/x86/entry/syscalls/syscall_64.tbl@@ -330,6 +330,7 @@ 321 common bpf sys_bpf 322 64 execveat stub_execveat 323 common userfaultfd sys_userfaultfd +324 common mlock2 sys_mlock2 # # x32-specific system call numbers start at 512 to avoid cache impact
diff --git a/include/linux/syscalls.h b/include/linux/syscalls.h
index 0800131..890632c 100644
--- a/include/linux/syscalls.h
+++ b/include/linux/syscalls.h@@ -885,4 +885,6 @@ asmlinkage long sys_execveat(int dfd, const char __user *filename, const char __user *const __user *argv, const char __user *const __user *envp, int flags); +asmlinkage long sys_mlock2(unsigned long start, size_t len, int flags); + #endif
diff --git a/include/uapi/asm-generic/unistd.h b/include/uapi/asm-generic/unistd.h
index e016bd9..14a6013 100644
--- a/include/uapi/asm-generic/unistd.h
+++ b/include/uapi/asm-generic/unistd.h@@ -709,9 +709,11 @@ __SYSCALL(__NR_memfd_create, sys_memfd_create) __SYSCALL(__NR_bpf, sys_bpf) #define __NR_execveat 281 __SC_COMP(__NR_execveat, sys_execveat, compat_sys_execveat) +#define __NR_mlock2 282 +__SYSCALL(__NR_mlock2, sys_mlock2) #undef __NR_syscalls -#define __NR_syscalls 282 +#define __NR_syscalls 283 /* * All syscalls below here should go away really,
diff --git a/kernel/sys_ni.c b/kernel/sys_ni.c
index 03c3875..8de5b26 100644
--- a/kernel/sys_ni.c
+++ b/kernel/sys_ni.c@@ -194,6 +194,7 @@ cond_syscall(sys_mlock); cond_syscall(sys_munlock); cond_syscall(sys_mlockall); cond_syscall(sys_munlockall); +cond_syscall(sys_mlock2); cond_syscall(sys_mincore); cond_syscall(sys_madvise); cond_syscall(sys_mremap);
diff --git a/mm/mlock.c b/mm/mlock.c
index c32ad8f..a23a533 100644
--- a/mm/mlock.c
+++ b/mm/mlock.c@@ -644,6 +644,14 @@ SYSCALL_DEFINE2(mlock, unsigned long, start, size_t, len) return do_mlock(start, len, VM_LOCKED); } +SYSCALL_DEFINE3(mlock2, unsigned long, start, size_t, len, int, flags) +{ + if (flags) + return -EINVAL; + + return do_mlock(start, len, VM_LOCKED); +} + SYSCALL_DEFINE2(munlock, unsigned long, start, size_t, len) { int ret;
--
1.9.1