7 files changed, 34 insertions, 2 deletions

diff --git a/arch/x86/ia32/ia32entry.S b/arch/x86/ia32/ia32entry.S
index 430312ba6e3f..849a9d23c71d 100644
--- a/arch/x86/ia32/ia32entry.S
+++ b/arch/x86/ia32/ia32entry.S
@@ -847,4 +847,5 @@ ia32_sys_call_table:
         .quad sys_name_to_handle_at
         .quad compat_sys_open_by_handle_at
         .quad compat_sys_clock_adjtime
+        .quad sys_syncfs
 ia32_syscall_end:
diff --git a/arch/x86/include/asm/unistd_32.h b/arch/x86/include/asm/unistd_32.h
index ffaf183c619a..a755ef5e5977 100644
--- a/arch/x86/include/asm/unistd_32.h
+++ b/arch/x86/include/asm/unistd_32.h
@@ -349,10 +349,11 @@
 #define __NR_name_to_handle_at  341
 #define __NR_open_by_handle_at  342
 #define __NR_clock_adjtime      343
+#define __NR_syncfs             344
 
 #ifdef __KERNEL__
 
-#define NR_syscalls 344
+#define NR_syscalls 345
 
 #define __ARCH_WANT_IPC_PARSE_VERSION
 #define __ARCH_WANT_OLD_READDIR
diff --git a/arch/x86/include/asm/unistd_64.h b/arch/x86/include/asm/unistd_64.h
index 5466bea670e7..160fa76bd578 100644
--- a/arch/x86/include/asm/unistd_64.h
+++ b/arch/x86/include/asm/unistd_64.h
@@ -675,6 +675,8 @@ __SYSCALL(__NR_name_to_handle_at, sys_name_to_handle_at)
 __SYSCALL(__NR_open_by_handle_at, sys_open_by_handle_at)
 #define __NR_clock_adjtime                      305
 __SYSCALL(__NR_clock_adjtime, sys_clock_adjtime)
+#define __NR_syncfs                             306
+__SYSCALL(__NR_syncfs, sys_syncfs)
 
 #ifndef __NO_STUBS
 #define __ARCH_WANT_OLD_READDIR
diff --git a/arch/x86/kernel/syscall_table_32.S b/arch/x86/kernel/syscall_table_32.S
index 5f181742e8f9..abce34d5c79d 100644
--- a/arch/x86/kernel/syscall_table_32.S
+++ b/arch/x86/kernel/syscall_table_32.S
@@ -343,3 +343,4 @@ ENTRY(sys_call_table)
         .long sys_name_to_handle_at
         .long sys_open_by_handle_at
         .long sys_clock_adjtime
+        .long sys_syncfs
diff --git a/fs/sync.c b/fs/sync.c
index ba76b9623e7e..92ca208777d5 100644
--- a/fs/sync.c
+++ b/fs/sync.c
@@ -7,6 +7,7 @@
 #include <linux/fs.h>
 #include <linux/slab.h>
 #include <linux/module.h>
+#include <linux/namei.h>
 #include <linux/sched.h>
 #include <linux/writeback.h>
 #include <linux/syscalls.h>
@@ -128,6 +129,29 @@ void emergency_sync(void)
         }
 }
 
+/*
+ * sync a single super
+ */
+SYSCALL_DEFINE1(syncfs, int, fd)
+{
+        struct file *file;
+        struct super_block *sb;
+        int ret;
+        int fput_needed;
+
+        file = fget_light(fd, &fput_needed);
+        if (!file)
+                return -EBADF;
+        sb = file->f_dentry->d_sb;
+
+        down_read(&sb->s_umount);
+        ret = sync_filesystem(sb);
+        up_read(&sb->s_umount);
+
+        fput_light(file, fput_needed);
+        return ret;
+}
+
 /**
  * vfs_fsync_range - helper to sync a range of data & metadata to disk
  * @file:               file to sync
diff --git a/include/asm-generic/unistd.h b/include/asm-generic/unistd.h
index d94f447c667a..176b825add52 100644
--- a/include/asm-generic/unistd.h
+++ b/include/asm-generic/unistd.h
@@ -652,9 +652,11 @@ __SYSCALL(__NR_name_to_handle_at, sys_name_to_handle_at)
 __SYSCALL(__NR_open_by_handle_at, sys_open_by_handle_at)
 #define __NR_clock_adjtime 266
 __SYSCALL(__NR_clock_adjtime, sys_clock_adjtime)
+#define __NR_syncfs 264
+__SYSCALL(__NR_syncfs, sys_syncfs)
 
 #undef __NR_syscalls
-#define __NR_syscalls 267
+#define __NR_syscalls 268
 
 /*
  * All syscalls below here should go away really,
diff --git a/include/linux/syscalls.h b/include/linux/syscalls.h
index 1f5c18e6f4f1..83ecc1749ef6 100644
--- a/include/linux/syscalls.h
+++ b/include/linux/syscalls.h
@@ -825,6 +825,7 @@ asmlinkage long sys_fanotify_init(unsigned int flags, unsigned int event_f_flags
 asmlinkage long sys_fanotify_mark(int fanotify_fd, unsigned int flags,
                                   u64 mask, int fd,
                                   const char  __user *pathname);
+asmlinkage long sys_syncfs(int fd);
 
 int kernel_execve(const char *filename, const char *const argv[], const char *const envp[]);