From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760531AbYEBJOs (ORCPT ); Fri, 2 May 2008 05:14:48 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1760699AbYEBJO1 (ORCPT ); Fri, 2 May 2008 05:14:27 -0400 Received: from web52001.mail.re2.yahoo.com ([206.190.49.248]:47473 "HELO web52001.mail.re2.yahoo.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1759724AbYEBJO0 (ORCPT ); Fri, 2 May 2008 05:14:26 -0400 DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=s1024; d=yahoo.com; h=X-YMail-OSG:Received:X-Mailer:Date:From:Subject:To:Cc:MIME-Version:Content-Type:Message-ID; b=Wx8Jz6NvONiNSW9HLMaJjrpjpoSgizYXNMD45qbUmjJmKpb347960Gwya5skKEjiX5kcfAVBlISKVAy9MwWC/nNqlgHMVYzoP66Puk5JTatlpOTZBVkySdxaZ9Wizg2LGo99EM/bdlOzerkx8Ic8H5jUoKFYFqbSEdRw/8BOmI8=; X-YMail-OSG: Tt2rpVgVM1naqPzoePiI25nRT_dfxtM5hc2gDQVvBSFTfzD_H_jQre.OfxObh9InNyF3vP2RM0BGF2e3o9xIRy7sZfr2wVfv2S78giMsZs6i_z8.ma5U8rrmkQ-- X-Mailer: YahooMailRC/975.23 YahooMailWebService/0.7.185 Date: Fri, 2 May 2008 02:14:25 -0700 (PDT) From: Matti Linnanvuori Subject: [patch] fs: remove local variable copy of f_pos to enable thread-safe updates To: viro@zeniv.linux.org.uk, linux-fsdevel@vger.kernel.org Cc: linux-kernel@vger.kernel.org MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Message-ID: <91456.70679.qm@web52001.mail.re2.yahoo.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Matti Linnanvuori Remove local variable copy of f_pos to enable thread-safe updates in implementation functions of system calls read, readv, write and writev. Signed-off-by: Matti Linnanvuori --- --- linux-next/fs/fs-read_write.c 2008-05-02 11:54:04.715996700 +0300 +++ linux-2.6/fs/fs-read_write.c 2008-05-02 11:57:17.011641000 +0300 @@ -348,16 +348,6 @@ ssize_t vfs_write(struct file *file, con EXPORT_SYMBOL(vfs_write); -static inline loff_t file_pos_read(struct file *file) -{ - return file->f_pos; -} - -static inline void file_pos_write(struct file *file, loff_t pos) -{ - file->f_pos = pos; -} - asmlinkage ssize_t sys_read(unsigned int fd, char __user * buf, size_t count) { struct file *file; @@ -366,10 +356,8 @@ asmlinkage ssize_t sys_read(unsigned int file = fget_light(fd, &fput_needed); if (file) { - loff_t pos = file_pos_read(file); trace_mark(fs_read, "fd %u count %zu", fd, count); - ret = vfs_read(file, buf, count, &pos); - file_pos_write(file, pos); + ret = vfs_read(file, buf, count, &file->f_pos); fput_light(file, fput_needed); } @@ -384,10 +372,8 @@ asmlinkage ssize_t sys_write(unsigned in file = fget_light(fd, &fput_needed); if (file) { - loff_t pos = file_pos_read(file); trace_mark(fs_write, "fd %u count %zu", fd, count); - ret = vfs_write(file, buf, count, &pos); - file_pos_write(file, pos); + ret = vfs_write(file, buf, count, &file->f_pos); fput_light(file, fput_needed); } @@ -679,10 +665,8 @@ sys_readv(unsigned long fd, const struct file = fget_light(fd, &fput_needed); if (file) { - loff_t pos = file_pos_read(file); trace_mark(fs_readv, "fd %lu vlen %lu", fd, vlen); - ret = vfs_readv(file, vec, vlen, &pos); - file_pos_write(file, pos); + ret = vfs_readv(file, vec, vlen, &file->f_pos); fput_light(file, fput_needed); } @@ -701,10 +685,8 @@ sys_writev(unsigned long fd, const struc file = fget_light(fd, &fput_needed); if (file) { - loff_t pos = file_pos_read(file); trace_mark(fs_writev, "fd %lu vlen %lu", fd, vlen); - ret = vfs_writev(file, vec, vlen, &pos); - file_pos_write(file, pos); + ret = vfs_writev(file, vec, vlen, &file->f_pos); fput_light(file, fput_needed); } ____________________________________________________________________________________ Be a better friend, newshound, and know-it-all with Yahoo! Mobile. Try it now. http://mobile.yahoo.com/;_ylt=Ahu06i62sR8HDtDypao8Wcj9tAcJ