diff options
Diffstat (limited to 'fs/sync.c')
| -rw-r--r-- | fs/sync.c | 48 |
1 files changed, 37 insertions, 11 deletions
diff --git a/fs/sync.c b/fs/sync.c index 2967562d416..0921d6d4b5e 100644 --- a/fs/sync.c +++ b/fs/sync.c @@ -75,14 +75,39 @@ int file_fsync(struct file *filp, struct dentry *dentry, int datasync) return ret; } -long do_fsync(struct file *file, int datasync) +/** + * vfs_fsync - perform a fsync or fdatasync on a file + * @file: file to sync + * @dentry: dentry of @file + * @data: only perform a fdatasync operation + * + * Write back data and metadata for @file to disk. If @datasync is + * set only metadata needed to access modified file data is written. + * + * In case this function is called from nfsd @file may be %NULL and + * only @dentry is set. This can only happen when the filesystem + * implements the export_operations API. + */ +int vfs_fsync(struct file *file, struct dentry *dentry, int datasync) { - int ret; - int err; - struct address_space *mapping = file->f_mapping; + const struct file_operations *fop; + struct address_space *mapping; + int err, ret; + + /* + * Get mapping and operations from the file in case we have + * as file, or get the default values for them in case we + * don't have a struct file available. Damn nfsd.. + */ + if (file) { + mapping = file->f_mapping; + fop = file->f_op; + } else { + mapping = dentry->d_inode->i_mapping; + fop = dentry->d_inode->i_fop; + } - if (!file->f_op || !file->f_op->fsync) { - /* Why? We can still call filemap_fdatawrite */ + if (!fop || !fop->fsync) { ret = -EINVAL; goto out; } @@ -94,7 +119,7 @@ long do_fsync(struct file *file, int datasync) * livelocks in fsync_buffers_list(). */ mutex_lock(&mapping->host->i_mutex); - err = file->f_op->fsync(file, file->f_path.dentry, datasync); + err = fop->fsync(file, dentry, datasync); if (!ret) ret = err; mutex_unlock(&mapping->host->i_mutex); @@ -104,15 +129,16 @@ long do_fsync(struct file *file, int datasync) out: return ret; } +EXPORT_SYMBOL(vfs_fsync); -static long __do_fsync(unsigned int fd, int datasync) +static int do_fsync(unsigned int fd, int datasync) { struct file *file; int ret = -EBADF; file = fget(fd); if (file) { - ret = do_fsync(file, datasync); + ret = vfs_fsync(file, file->f_path.dentry, datasync); fput(file); } return ret; @@ -120,12 +146,12 @@ static long __do_fsync(unsigned int fd, int datasync) 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); } /* |