On Tue, 30 Nov 2010 10:54:31 +0300 Pavel Shilovsky <[email protected]> wrote:
> On strict cache mode if we don't have Exclusive oplock we write a data to > the server through cifs_user_write. Then if we Level II oplock store it in > the cache, otherwise - invalidate inode pages affected by this writing. > > Signed-off-by: Pavel Shilovsky <[email protected]> > --- > fs/cifs/cifsfs.c | 51 ++++++++++++++++++++++++++++++++++++++++++++++----- > 1 files changed, 46 insertions(+), 5 deletions(-) > > diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c > index 370acdc..df17261 100644 > --- a/fs/cifs/cifsfs.c > +++ b/fs/cifs/cifsfs.c > @@ -611,12 +611,53 @@ static ssize_t cifs_file_aio_read(struct kiocb *iocb, > const struct iovec *iov, > static ssize_t cifs_file_aio_write(struct kiocb *iocb, const struct iovec > *iov, > unsigned long nr_segs, loff_t pos) > { > - struct inode *inode = iocb->ki_filp->f_path.dentry->d_inode; > - ssize_t written; > + struct inode *inode; > + struct cifs_sb_info *cifs_sb; > + ssize_t written = 0, retval; > + unsigned long i; > + > + inode = iocb->ki_filp->f_path.dentry->d_inode; > + > + if (CIFS_I(inode)->clientCanCacheAll) > + return generic_file_aio_write(iocb, iov, nr_segs, pos); > + > + cifs_sb = CIFS_SB(iocb->ki_filp->f_path.dentry->d_sb); > + > + if ((cifs_sb->mnt_cifs_flags & CIFS_MOUNT_STRICT_IO) == 0) { > + int rc; > + > + written = generic_file_aio_write(iocb, iov, nr_segs, pos); > + > + rc = filemap_fdatawrite(inode->i_mapping); > + if (rc) > + cFYI(1, "cifs_file_aio_write: %d rc on %p inode", > + rc, inode); > + return written; > + } > + > + /* > + * In strict cache mode we need to write the data to the server exactly > + * from the pos to pos+len-1 rather than flush all affected pages > + * because it may cause a error with mandatory locks on these pages but > + * not on the region from pos to ppos+len-1. > + */ > + > + for (i = 0; i < nr_segs; i++) { > + retval = cifs_user_write(iocb->ki_filp, iov[i].iov_base, > + iov[i].iov_len, &pos); > + if (retval < 0) { > + written = written ? written : retval; > + break; > + } > + > + written += retval; > + } > + Same problem as with the read patch. This is going to mean a bunch of small writes on the wire just because the application sent you a set of small iovecs. I think you want to batch those up into smaller set of writes. > + iocb->ki_pos = pos; > + > + if (written > 0) > + CIFS_I(inode)->invalid_mapping = true; > > - written = generic_file_aio_write(iocb, iov, nr_segs, pos); > - if (!CIFS_I(inode)->clientCanCacheAll) > - filemap_fdatawrite(inode->i_mapping); > return written; > } > -- Jeff Layton <[email protected]> -- To unsubscribe from this list: send the line "unsubscribe linux-cifs" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
