[PATCH] fsync: extract internal code

Pull the guts out of do_fsync() - we can use it elsewhere.

Cc: Hugh Dickins <hugh@veritas.com>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

2 files changed, 24 insertions, 20 deletions

diff --git a/fs/buffer.c b/fs/buffer.c
index 24262ea8cc50..6d77ce9f54e5 100644
--- a/fs/buffer.c
+++ b/fs/buffer.c
@@ -327,31 +327,24 @@ int file_fsync(struct file *filp, struct dentry *dentry, int datasync)
         return ret;
 }
 
-static long do_fsync(unsigned int fd, int datasync)
+long do_fsync(struct file *file, int datasync)
 {
-        struct file * file;
-        struct address_space *mapping;
-        int ret, err;
-
-        ret = -EBADF;
-        file = fget(fd);
-        if (!file)
-                goto out;
+        int ret;
+        int err;
+        struct address_space *mapping = file->f_mapping;
 
-        ret = -EINVAL;
         if (!file->f_op || !file->f_op->fsync) {
                 /* Why?  We can still call filemap_fdatawrite */
-                goto out_putf;
+                ret = -EINVAL;
+                goto out;
         }
 
-        mapping = file->f_mapping;
-
         current->flags |= PF_SYNCWRITE;
         ret = filemap_fdatawrite(mapping);
 
         /*
-         * We need to protect against concurrent writers,
-         * which could cause livelocks in fsync_buffers_list
+         * We need to protect against concurrent writers, which could cause
+         * livelocks in fsync_buffers_list().
          */
         mutex_lock(&mapping->host->i_mutex);
         err = file->f_op->fsync(file, file->f_dentry, datasync);
@@ -362,21 +355,31 @@ static long do_fsync(unsigned int fd, int datasync)
         if (!ret)
                 ret = err;
         current->flags &= ~PF_SYNCWRITE;
-
-out_putf:
-        fput(file);
 out:
         return ret;
 }
 
+static long __do_fsync(unsigned int fd, int datasync)
+{
+        struct file *file;
+        int ret = -EBADF;
+
+        file = fget(fd);
+        if (file) {
+                ret = do_fsync(file, datasync);
+                fput(file);
+        }
+        return ret;
+}
+
 asmlinkage long sys_fsync(unsigned int fd)
 {
-        return do_fsync(fd, 0);
+        return __do_fsync(fd, 0);
 }
 
 asmlinkage long sys_fdatasync(unsigned int fd)
 {
-        return do_fsync(fd, 1);
+        return __do_fsync(fd, 1);
 }
 
 /*
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 092cfaee0cd2..215696a0f16f 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -1478,6 +1478,7 @@ extern int wait_on_page_writeback_range(struct address_space *mapping,
 extern int __filemap_fdatawrite_range(struct address_space *mapping,
                                 loff_t start, loff_t end, int sync_mode);
 
+extern long do_fsync(struct file *file, int datasync);
 extern void sync_supers(void);
 extern void sync_filesystems(int wait);
 extern void emergency_sync(void);