From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754316AbZIOOLD (ORCPT ); Tue, 15 Sep 2009 10:11:03 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754197AbZIOOK6 (ORCPT ); Tue, 15 Sep 2009 10:10:58 -0400 Received: from cantor2.suse.de ([195.135.220.15]:37721 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754111AbZIOOK4 (ORCPT ); Tue, 15 Sep 2009 10:10:56 -0400 Date: Tue, 15 Sep 2009 16:10:57 +0200 From: Jan Kara To: Christoph Hellwig Cc: Jan Kara , linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org, akpm@linux-foundation.org, drepper@redhat.com, viro@zeniv.linux.org.uk, kyle@mcmartin.ca, sct@redhat.com Subject: Re: [PATCH] implement posix O_SYNC and O_DSYNC semantics Message-ID: <20090915141057.GH12169@duck.suse.cz> References: <20090914165419.GD25549@duck.suse.cz> <20090915131252.GA13754@lst.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20090915131252.GA13754@lst.de> User-Agent: Mutt/1.5.17 (2007-11-01) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue 15-09-09 15:12:52, Christoph Hellwig wrote: > While Linux provided an O_SYNC flag basically since day 1, it took until > Linux 2.4.0-test12pre2 to actually get it implemented for filesystems, > since that day we had generic_osync_around with only minor changes and the > great "For now, when the user asks for O_SYNC, we'll actually give O_DSYNC" > comment. This patch intends to actually give us real O_SYNC semantics > in addition to the O_DSYNC semantics. After Jan's O_SYNC patches which > are required before this patch it's actually surprisingly simple, we > just need to figure out when to set the datasync flag to vfs_fsync_range > and when not. > > This patch renames the existing O_SYNC flag to O_DSYNC while keeping > it's numerical value to keep binary compatibility, and adds a new real > O_SYNC flag. To guarantee backwards compatiblity it is defined as > expanding to both the O_DSYNC and the new additional binary flag > (__O_SYNC) to make sure we are backwards-compatible when compiled against > the new headers. > > This also means that all places that don't care about the differences > can just check O_DSYNC and get the right behaviour for O_SYNC, too - only > places that actuall care need to check __O_SYNC in addition. Drivers > and network filesystems have been updated in a fail safe way to always > do the full sync magic if O_DSYNC is set. The few places setting O_SYNC > for lower layers are kept that way for now to stay failsafe. > > We enforce that O_DSYNC is set when __O_SYNC is set early in the > open path to make sure we always get these sane options. > > Note that parisc really fucked up their headers as they already define > a O_DSYNC that has always been a no-op. We try to repair it by using it > for the new O_DSYNC and redefinining O_SYNC to send both the traditional > O_SYNC numerical value _and_ the O_DSYNC one. > > > Signed-off-by: Christoph Hellwig > Acked-by: Trond Myklebust The patch looks fine now. Acked-by: Jan Kara > Index: linux-2.6/arch/x86/mm/pat.c > =================================================================== > --- linux-2.6.orig/arch/x86/mm/pat.c 2009-09-15 00:46:32.911256267 -0300 > +++ linux-2.6/arch/x86/mm/pat.c 2009-09-15 09:41:27.301253948 -0300 > @@ -541,7 +541,7 @@ int phys_mem_access_prot_allowed(struct > if (!range_is_allowed(pfn, size)) > return 0; > > - if (file->f_flags & O_SYNC) { > + if (file->f_flags & O_DSYNC) { > flags = _PAGE_CACHE_UC_MINUS; > } > > Index: linux-2.6/drivers/char/mem.c > =================================================================== > --- linux-2.6.orig/drivers/char/mem.c 2009-09-15 00:46:33.096254330 -0300 > +++ linux-2.6/drivers/char/mem.c 2009-09-15 09:41:27.302253936 -0300 > @@ -44,7 +44,7 @@ static inline int uncached_access(struct > { > #if defined(CONFIG_IA64) > /* > - * On ia64, we ignore O_SYNC because we cannot tolerate memory attribute aliases. > + * On ia64, we ignore O_DSYNC because we cannot tolerate memory attribute aliases. > */ > return !(efi_mem_attributes(addr) & EFI_MEMORY_WB); > #elif defined(CONFIG_MIPS) > @@ -57,9 +57,9 @@ static inline int uncached_access(struct > #else > /* > * Accessing memory above the top the kernel knows about or through a file pointer > - * that was marked O_SYNC will be done non-cached. > + * that was marked O_DSYNC will be done non-cached. > */ > - if (file->f_flags & O_SYNC) > + if (file->f_flags & O_DSYNC) > return 1; > return addr >= __pa(high_memory); > #endif > Index: linux-2.6/drivers/staging/me4000/me4000.c > =================================================================== > --- linux-2.6.orig/drivers/staging/me4000/me4000.c 2009-09-15 00:46:33.130254399 -0300 > +++ linux-2.6/drivers/staging/me4000/me4000.c 2009-09-15 09:41:27.305253618 -0300 > @@ -1985,8 +1985,8 @@ static ssize_t me4000_ao_write_cont(stru > spin_unlock_irqrestore(&ao_context->int_lock, flags); > } > > - /* Wait until the state machine is stopped if O_SYNC is set */ > - if (filep->f_flags & O_SYNC) { > + /* Wait until the state machine is stopped if O_DSYNC is set */ > + if (filep->f_flags & O_DSYNC) { > while (inl(ao_context->status_reg) & > ME4000_AO_STATUS_BIT_FSM) { > interruptible_sleep_on_timeout(&queue, 1); > Index: linux-2.6/drivers/usb/gadget/file_storage.c > =================================================================== > --- linux-2.6.orig/drivers/usb/gadget/file_storage.c 2009-09-15 00:46:33.138253951 -0300 > +++ linux-2.6/drivers/usb/gadget/file_storage.c 2009-09-15 09:41:27.311253752 -0300 > @@ -1713,7 +1713,7 @@ static int do_write(struct fsg_dev *fsg) > } > if (fsg->cmnd[1] & 0x08) { // FUA > spin_lock(&curlun->filp->f_lock); > - curlun->filp->f_flags |= O_SYNC; > + curlun->filp->f_flags |= O_DSYNC; > spin_unlock(&curlun->filp->f_lock); > } > } > Index: linux-2.6/fs/afs/write.c > =================================================================== > --- linux-2.6.orig/fs/afs/write.c 2009-09-15 00:46:33.144254016 -0300 > +++ linux-2.6/fs/afs/write.c 2009-09-15 09:41:27.316253550 -0300 > @@ -692,8 +692,9 @@ ssize_t afs_file_write(struct kiocb *ioc > } > > /* return error values for O_SYNC and IS_SYNC() */ > - if (IS_SYNC(&vnode->vfs_inode) || iocb->ki_filp->f_flags & O_SYNC) { > - ret = afs_fsync(iocb->ki_filp, dentry, 1); > + if (IS_SYNC(&vnode->vfs_inode) || iocb->ki_filp->f_flags & O_DSYNC) { > + ret = afs_fsync(iocb->ki_filp, dentry, > + (iocb->ki_filp->f_flags & __O_SYNC) ? 0 : 1); > if (ret < 0) > result = ret; > } > Index: linux-2.6/fs/btrfs/file.c > =================================================================== > --- linux-2.6.orig/fs/btrfs/file.c 2009-09-15 00:46:33.151254279 -0300 > +++ linux-2.6/fs/btrfs/file.c 2009-09-15 09:41:27.316253550 -0300 > @@ -924,7 +924,7 @@ static ssize_t btrfs_file_write(struct f > unsigned long last_index; > int will_write; > > - will_write = ((file->f_flags & O_SYNC) || IS_SYNC(inode) || > + will_write = ((file->f_flags & O_DSYNC) || IS_SYNC(inode) || > (file->f_flags & O_DIRECT)); > > nrptrs = min((count + PAGE_CACHE_SIZE - 1) / PAGE_CACHE_SIZE, > @@ -1077,7 +1077,7 @@ out_nolock: > if (err) > num_written = err; > > - if ((file->f_flags & O_SYNC) || IS_SYNC(inode)) { > + if ((file->f_flags & O_DSYNC) || IS_SYNC(inode)) { > trans = btrfs_start_transaction(root, 1); > ret = btrfs_log_dentry_safe(trans, root, > file->f_dentry); > Index: linux-2.6/fs/cifs/dir.c > =================================================================== > --- linux-2.6.orig/fs/cifs/dir.c 2009-09-15 00:46:33.156254147 -0300 > +++ linux-2.6/fs/cifs/dir.c 2009-09-15 09:41:27.319254141 -0300 > @@ -214,7 +214,8 @@ int cifs_posix_open(char *full_path, str > posix_flags |= SMB_O_TRUNC; > if (oflags & O_APPEND) > posix_flags |= SMB_O_APPEND; > - if (oflags & O_SYNC) > + /* be safe and imply O_SYNC for O_DSYNC */ > + if (oflags & O_DSYNC) > posix_flags |= SMB_O_SYNC; > if (oflags & O_DIRECTORY) > posix_flags |= SMB_O_DIRECTORY; > Index: linux-2.6/fs/cifs/file.c > =================================================================== > --- linux-2.6.orig/fs/cifs/file.c 2009-09-15 00:46:33.162254422 -0300 > +++ linux-2.6/fs/cifs/file.c 2009-09-15 09:41:27.323254719 -0300 > @@ -96,8 +96,10 @@ static inline fmode_t cifs_posix_convert > reopening a file. They had their effect on the original open */ > if (flags & O_APPEND) > posix_flags |= (fmode_t)O_APPEND; > - if (flags & O_SYNC) > - posix_flags |= (fmode_t)O_SYNC; > + if (flags & O_DSYNC) > + posix_flags |= (fmode_t)O_DSYNC; > + if (flags & __O_SYNC) > + posix_flags |= (fmode_t)__O_SYNC; > if (flags & O_DIRECTORY) > posix_flags |= (fmode_t)O_DIRECTORY; > if (flags & O_NOFOLLOW) > Index: linux-2.6/fs/namei.c > =================================================================== > --- linux-2.6.orig/fs/namei.c 2009-09-15 00:46:33.168253161 -0300 > +++ linux-2.6/fs/namei.c 2009-09-15 09:45:26.694256679 -0300 > @@ -1678,6 +1678,15 @@ struct file *do_filp_open(int dfd, const > int will_write; > int flag = open_to_namei_flags(open_flag); > > + /* > + * O_SYNC is implemented as __O_SYNC|O_DSYNC. As many places only > + * check for O_DSYNC if the need any syncing at all we enforce it's > + * always set instead of having to deal with possibly weird behaviour > + * for malicious applications setting only __O_SYNC. > + */ > + if (open_flag & __O_SYNC) > + open_flag |= O_DSYNC; > + > if (!acc_mode) > acc_mode = MAY_OPEN | ACC_MODE(flag); > > Index: linux-2.6/fs/nfs/file.c > =================================================================== > --- linux-2.6.orig/fs/nfs/file.c 2009-09-15 00:46:33.174254134 -0300 > +++ linux-2.6/fs/nfs/file.c 2009-09-15 09:41:27.330253653 -0300 > @@ -580,7 +580,7 @@ static int nfs_need_sync_write(struct fi > { > struct nfs_open_context *ctx; > > - if (IS_SYNC(inode) || (filp->f_flags & O_SYNC)) > + if (IS_SYNC(inode) || (filp->f_flags & O_DSYNC)) > return 1; > ctx = nfs_file_open_context(filp); > if (test_bit(NFS_CONTEXT_ERROR_WRITE, &ctx->flags)) > @@ -621,7 +621,7 @@ static ssize_t nfs_file_write(struct kio > > nfs_add_stats(inode, NFSIOS_NORMALWRITTENBYTES, count); > result = generic_file_aio_write(iocb, iov, nr_segs, pos); > - /* Return error values for O_SYNC and IS_SYNC() */ > + /* Return error values for O_DSYNC and IS_SYNC() */ > if (result >= 0 && nfs_need_sync_write(iocb->ki_filp, inode)) { > int err = nfs_do_fsync(nfs_file_open_context(iocb->ki_filp), inode); > if (err < 0) > Index: linux-2.6/fs/nfs/write.c > =================================================================== > --- linux-2.6.orig/fs/nfs/write.c 2009-09-15 00:46:33.180254200 -0300 > +++ linux-2.6/fs/nfs/write.c 2009-09-15 09:41:27.332254187 -0300 > @@ -774,7 +774,7 @@ int nfs_updatepage(struct file *file, st > */ > if (nfs_write_pageuptodate(page, inode) && > inode->i_flock == NULL && > - !(file->f_flags & O_SYNC)) { > + !(file->f_flags & O_DSYNC)) { > count = max(count + offset, nfs_page_length(page)); > offset = 0; > } > Index: linux-2.6/include/asm-generic/fcntl.h > =================================================================== > --- linux-2.6.orig/include/asm-generic/fcntl.h 2009-09-15 00:46:33.211253817 -0300 > +++ linux-2.6/include/asm-generic/fcntl.h 2009-09-15 09:41:27.335253940 -0300 > @@ -3,8 +3,6 @@ > > #include > > -/* open/fcntl - O_SYNC is only implemented on blocks devices and on files > - located on an ext2 file system */ > #define O_ACCMODE 00000003 > #define O_RDONLY 00000000 > #define O_WRONLY 00000001 > @@ -27,8 +25,8 @@ > #ifndef O_NONBLOCK > #define O_NONBLOCK 00004000 > #endif > -#ifndef O_SYNC > -#define O_SYNC 00010000 > +#ifndef O_DSYNC > +#define O_DSYNC 00010000 /* used to be O_SYNC, see below */ > #endif > #ifndef FASYNC > #define FASYNC 00020000 /* fcntl, for BSD compatibility */ > @@ -51,6 +49,25 @@ > #ifndef O_CLOEXEC > #define O_CLOEXEC 02000000 /* set close_on_exec */ > #endif > + > +/* > + * Before Linux 2.6.32 only O_DSYNC semantics were implemented, but using > + * the O_SYNC flag. We continue to use the existing numerical value > + * for O_DSYNC semantics now, but using the correct symbolic name for it. > + * This new value is used to request true Posix O_SYNC semantics. It is > + * defined in this strange way to make sure applications compiled against > + * new headers get at least O_DSYNC semantics on older kernels. > + * > + * This has the nice side-effect that we can simply test for O_DSYNC > + * wherever we do not care if O_DSYNC or O_SYNC is used. > + * > + * Note: __O_SYNC must never be used directly. > + */ > +#ifndef O_SYNC > +#define __O_SYNC 04000000 > +#define O_SYNC (__O_SYNC|O_DSYNC) > +#endif > + > #ifndef O_NDELAY > #define O_NDELAY O_NONBLOCK > #endif > Index: linux-2.6/fs/ocfs2/file.c > =================================================================== > --- linux-2.6.orig/fs/ocfs2/file.c 2009-09-15 00:46:33.186253776 -0300 > +++ linux-2.6/fs/ocfs2/file.c 2009-09-15 09:41:27.338254042 -0300 > @@ -1878,7 +1878,7 @@ out_dio: > /* buffered aio wouldn't have proper lock coverage today */ > BUG_ON(ret == -EIOCBQUEUED && !(file->f_flags & O_DIRECT)); > > - if ((file->f_flags & O_SYNC && !direct_io) || IS_SYNC(inode)) { > + if ((file->f_flags & O_DSYNC && !direct_io) || IS_SYNC(inode)) { > ret = filemap_fdatawrite_range(file->f_mapping, pos, > pos + count - 1); > if (ret < 0) > Index: linux-2.6/fs/ubifs/file.c > =================================================================== > --- linux-2.6.orig/fs/ubifs/file.c 2009-09-15 00:46:33.192253912 -0300 > +++ linux-2.6/fs/ubifs/file.c 2009-09-15 09:41:27.341254213 -0300 > @@ -1403,7 +1403,7 @@ static ssize_t ubifs_aio_write(struct ki > if (ret < 0) > return ret; > > - if (ret > 0 && (IS_SYNC(inode) || iocb->ki_filp->f_flags & O_SYNC)) { > + if (ret > 0 && (IS_SYNC(inode) || iocb->ki_filp->f_flags & O_DSYNC)) { > err = ubifs_sync_wbufs_by_inode(c, inode); > if (err) > return err; > Index: linux-2.6/fs/xfs/linux-2.6/xfs_lrw.c > =================================================================== > --- linux-2.6.orig/fs/xfs/linux-2.6/xfs_lrw.c 2009-09-15 00:46:33.198253488 -0300 > +++ linux-2.6/fs/xfs/linux-2.6/xfs_lrw.c 2009-09-15 09:41:27.344254176 -0300 > @@ -811,7 +811,7 @@ write_retry: > XFS_STATS_ADD(xs_write_bytes, ret); > > /* Handle various SYNC-type writes */ > - if ((file->f_flags & O_SYNC) || IS_SYNC(inode)) { > + if ((file->f_flags & O_DSYNC) || IS_SYNC(inode)) { > int error2; > > xfs_iunlock(xip, iolock); > Index: linux-2.6/sound/core/rawmidi.c > =================================================================== > --- linux-2.6.orig/sound/core/rawmidi.c 2009-09-15 00:46:33.219253718 -0300 > +++ linux-2.6/sound/core/rawmidi.c 2009-09-15 09:41:27.347253859 -0300 > @@ -1258,7 +1258,7 @@ static ssize_t snd_rawmidi_write(struct > break; > count -= count1; > } > - if (file->f_flags & O_SYNC) { > + if (file->f_flags & O_DSYNC) { > spin_lock_irq(&runtime->lock); > while (runtime->avail != runtime->buffer_size) { > wait_queue_t wait; > Index: linux-2.6/arch/alpha/include/asm/fcntl.h > =================================================================== > --- linux-2.6.orig/arch/alpha/include/asm/fcntl.h 2009-09-15 00:46:32.945006724 -0300 > +++ linux-2.6/arch/alpha/include/asm/fcntl.h 2009-09-15 09:41:27.348253497 -0300 > @@ -1,8 +1,6 @@ > #ifndef _ALPHA_FCNTL_H > #define _ALPHA_FCNTL_H > > -/* open/fcntl - O_SYNC is only implemented on blocks devices and on files > - located on an ext2 file system */ > #define O_CREAT 01000 /* not fcntl */ > #define O_TRUNC 02000 /* not fcntl */ > #define O_EXCL 04000 /* not fcntl */ > @@ -10,13 +8,28 @@ > > #define O_NONBLOCK 00004 > #define O_APPEND 00010 > -#define O_SYNC 040000 > +#define O_DSYNC 040000 /* used to be O_SYNC, see below */ > #define O_DIRECTORY 0100000 /* must be a directory */ > #define O_NOFOLLOW 0200000 /* don't follow links */ > #define O_LARGEFILE 0400000 /* will be set by the kernel on every open */ > #define O_DIRECT 02000000 /* direct disk access - should check with OSF/1 */ > #define O_NOATIME 04000000 > #define O_CLOEXEC 010000000 /* set close_on_exec */ > +/* > + * Before Linux 2.6.32 only O_DSYNC semantics were implemented, but using > + * the O_SYNC flag. We continue to use the existing numerical value > + * for O_DSYNC semantics now, but using the correct symbolic name for it. > + * This new value is used to request true Posix O_SYNC semantics. It is > + * defined in this strange way to make sure applications compiled against > + * new headers get at least O_DSYNC semantics on older kernels. > + * > + * This has the nice side-effect that we can simply test for O_DSYNC > + * wherever we do not care if O_DSYNC or O_SYNC is used. > + * > + * Note: __O_SYNC must never be used directly. > + */ > +#define __O_SYNC 020000000 > +#define O_SYNC (__O_SYNC|O_DSYNC) > > #define F_GETLK 7 > #define F_SETLK 8 > Index: linux-2.6/arch/blackfin/include/asm/fcntl.h > =================================================================== > --- linux-2.6.orig/arch/blackfin/include/asm/fcntl.h 2009-09-15 00:46:32.978006455 -0300 > +++ linux-2.6/arch/blackfin/include/asm/fcntl.h 2009-09-15 09:41:27.351254088 -0300 > @@ -1,8 +1,6 @@ > #ifndef _BFIN_FCNTL_H > #define _BFIN_FCNTL_H > > -/* open/fcntl - O_SYNC is only implemented on blocks devices and on files > - located on an ext2 file system */ > #define O_DIRECTORY 040000 /* must be a directory */ > #define O_NOFOLLOW 0100000 /* don't follow links */ > #define O_DIRECT 0200000 /* direct disk access hint - currently ignored */ > Index: linux-2.6/arch/mips/include/asm/fcntl.h > =================================================================== > --- linux-2.6.orig/arch/mips/include/asm/fcntl.h 2009-09-15 00:46:33.002006368 -0300 > +++ linux-2.6/arch/mips/include/asm/fcntl.h 2009-09-15 09:41:27.354254050 -0300 > @@ -10,7 +10,7 @@ > > > #define O_APPEND 0x0008 > -#define O_SYNC 0x0010 > +#define O_DSYNC 0x0010 /* used to be O_SYNC, see below */ > #define O_NONBLOCK 0x0080 > #define O_CREAT 0x0100 /* not fcntl */ > #define O_TRUNC 0x0200 /* not fcntl */ > @@ -18,6 +18,21 @@ > #define O_NOCTTY 0x0800 /* not fcntl */ > #define FASYNC 0x1000 /* fcntl, for BSD compatibility */ > #define O_LARGEFILE 0x2000 /* allow large file opens */ > +/* > + * Before Linux 2.6.32 only O_DSYNC semantics were implemented, but using > + * the O_SYNC flag. We continue to use the existing numerical value > + * for O_DSYNC semantics now, but using the correct symbolic name for it. > + * This new value is used to request true Posix O_SYNC semantics. It is > + * defined in this strange way to make sure applications compiled against > + * new headers get at least O_DSYNC semantics on older kernels. > + * > + * This has the nice side-effect that we can simply test for O_DSYNC > + * wherever we do not care if O_DSYNC or O_SYNC is used. > + * > + * Note: __O_SYNC must never be used directly. > + */ > +#define __O_SYNC 0x4000 > +#define O_SYNC (__O_SYNC|O_DSYNC) > #define O_DIRECT 0x8000 /* direct disk access hint */ > > #define F_GETLK 14 > Index: linux-2.6/arch/mips/kernel/kspd.c > =================================================================== > --- linux-2.6.orig/arch/mips/kernel/kspd.c 2009-09-15 00:46:33.021004807 -0300 > +++ linux-2.6/arch/mips/kernel/kspd.c 2009-09-15 09:41:27.357254082 -0300 > @@ -82,6 +82,7 @@ static int sp_stopping = 0; > #define MTSP_O_SHLOCK 0x0010 > #define MTSP_O_EXLOCK 0x0020 > #define MTSP_O_ASYNC 0x0040 > +/* XXX: check which of these is actually O_SYNC vs O_DSYNC */ > #define MTSP_O_FSYNC O_SYNC > #define MTSP_O_NOFOLLOW 0x0100 > #define MTSP_O_SYNC 0x0080 > Index: linux-2.6/arch/mips/lemote/lm2e/mem.c > =================================================================== > --- linux-2.6.orig/arch/mips/lemote/lm2e/mem.c 2009-09-15 00:46:33.054254081 -0300 > +++ linux-2.6/arch/mips/lemote/lm2e/mem.c 2009-09-15 09:41:27.357254082 -0300 > @@ -11,7 +11,7 @@ > /* override of arch/mips/mm/cache.c: __uncached_access */ > int __uncached_access(struct file *file, unsigned long addr) > { > - if (file->f_flags & O_SYNC) > + if (file->f_flags & O_DSYNC) > return 1; > > /* > Index: linux-2.6/arch/mips/mm/cache.c > =================================================================== > --- linux-2.6.orig/arch/mips/mm/cache.c 2009-09-15 00:46:33.074254183 -0300 > +++ linux-2.6/arch/mips/mm/cache.c 2009-09-15 09:41:27.360254044 -0300 > @@ -194,7 +194,7 @@ void __devinit cpu_cache_init(void) > > int __weak __uncached_access(struct file *file, unsigned long addr) > { > - if (file->f_flags & O_SYNC) > + if (file->f_flags & O_DSYNC) > return 1; > > return addr >= __pa(high_memory); > Index: linux-2.6/arch/parisc/include/asm/fcntl.h > =================================================================== > --- linux-2.6.orig/arch/parisc/include/asm/fcntl.h 2009-09-15 00:46:33.082254364 -0300 > +++ linux-2.6/arch/parisc/include/asm/fcntl.h 2009-09-15 09:41:27.363254007 -0300 > @@ -1,14 +1,13 @@ > #ifndef _PARISC_FCNTL_H > #define _PARISC_FCNTL_H > > -/* open/fcntl - O_SYNC is only implemented on blocks devices and on files > - located on an ext2 file system */ > #define O_APPEND 000000010 > #define O_BLKSEEK 000000100 /* HPUX only */ > #define O_CREAT 000000400 /* not fcntl */ > #define O_EXCL 000002000 /* not fcntl */ > #define O_LARGEFILE 000004000 > -#define O_SYNC 000100000 > +#define __O_SYNC 000100000 > +#define O_SYNC (__O_SYNC|O_DSYNC) > #define O_NONBLOCK 000200004 /* HPUX has separate NDELAY & NONBLOCK */ > #define O_NOCTTY 000400000 /* not fcntl */ > #define O_DSYNC 001000000 /* HPUX only */ > Index: linux-2.6/arch/sparc/include/asm/fcntl.h > =================================================================== > --- linux-2.6.orig/arch/sparc/include/asm/fcntl.h 2009-09-15 00:46:33.090254335 -0300 > +++ linux-2.6/arch/sparc/include/asm/fcntl.h 2009-09-15 09:41:27.367253956 -0300 > @@ -1,14 +1,12 @@ > #ifndef _SPARC_FCNTL_H > #define _SPARC_FCNTL_H > > -/* open/fcntl - O_SYNC is only implemented on blocks devices and on files > - located on an ext2 file system */ > #define O_APPEND 0x0008 > #define FASYNC 0x0040 /* fcntl, for BSD compatibility */ > #define O_CREAT 0x0200 /* not fcntl */ > #define O_TRUNC 0x0400 /* not fcntl */ > #define O_EXCL 0x0800 /* not fcntl */ > -#define O_SYNC 0x2000 > +#define O_DSYNC 0x2000 /* used to be O_SYNC, see below */ > #define O_NONBLOCK 0x4000 > #if defined(__sparc__) && defined(__arch64__) > #define O_NDELAY 0x0004 > @@ -20,6 +18,21 @@ > #define O_DIRECT 0x100000 /* direct disk access hint */ > #define O_NOATIME 0x200000 > #define O_CLOEXEC 0x400000 > +/* > + * Before Linux 2.6.32 only O_DSYNC semantics were implemented, but using > + * the O_SYNC flag. We continue to use the existing numerical value > + * for O_DSYNC semantics now, but using the correct symbolic name for it. > + * This new value is used to request true Posix O_SYNC semantics. It is > + * defined in this strange way to make sure applications compiled against > + * new headers get at least O_DSYNC semantics on older kernels. > + * > + * This has the nice side-effect that we can simply test for O_DSYNC > + * wherever we do not care if O_DSYNC or O_SYNC is used. > + * > + * Note: __O_SYNC must never be used directly. > + */ > +#define __O_SYNC 0x800000 > +#define O_SYNC (__O_SYNC|O_DSYNC) > > #define F_GETOWN 5 /* for sockets. */ > #define F_SETOWN 6 /* for sockets. */ > Index: linux-2.6/fs/sync.c > =================================================================== > --- linux-2.6.orig/fs/sync.c 2009-09-15 00:46:33.205253612 -0300 > +++ linux-2.6/fs/sync.c 2009-09-15 09:41:27.370254058 -0300 > @@ -287,10 +287,11 @@ SYSCALL_DEFINE1(fdatasync, unsigned int, > */ > int generic_write_sync(struct file *file, loff_t pos, loff_t count) > { > - if (!(file->f_flags & O_SYNC) && !IS_SYNC(file->f_mapping->host)) > + if (!(file->f_flags & O_DSYNC) && !IS_SYNC(file->f_mapping->host)) > return 0; > return vfs_fsync_range(file, file->f_path.dentry, pos, > - pos + count - 1, 1); > + pos + count - 1, > + (file->f_flags & __O_SYNC) ? 0 : 1); > } > EXPORT_SYMBOL(generic_write_sync); > -- Jan Kara SUSE Labs, CR