Module Name: src Committed By: martin Date: Sat Jan 17 11:49:09 UTC 2015
Modified Files: src/sys/fs/puffs [netbsd-7]: puffs_vnops.c Log Message: Pull up following revision(s) (requested by manu in ticket #423): sys/fs/puffs/puffs_vnops.c: revision 1.199 Make sure reads on empty files reach PUFFS filesystems Sending a read through the page cache will get the operation short-circuited. This is a problem with some filesystems that expect to receive the read operation in order to update atime. We fix that by bypassing the page cache when reading a file wich a size known to be zero. To generate a diff of this commit: cvs rdiff -u -r1.182.2.11 -r1.182.2.12 src/sys/fs/puffs/puffs_vnops.c Please note that diffs are not public domain; they are subject to the copyright notices on the relevant files.
Modified files: Index: src/sys/fs/puffs/puffs_vnops.c diff -u src/sys/fs/puffs/puffs_vnops.c:1.182.2.11 src/sys/fs/puffs/puffs_vnops.c:1.182.2.12 --- src/sys/fs/puffs/puffs_vnops.c:1.182.2.11 Sun Nov 9 10:09:32 2014 +++ src/sys/fs/puffs/puffs_vnops.c Sat Jan 17 11:49:09 2015 @@ -1,4 +1,4 @@ -/* $NetBSD: puffs_vnops.c,v 1.182.2.11 2014/11/09 10:09:32 msaitoh Exp $ */ +/* $NetBSD: puffs_vnops.c,v 1.182.2.12 2015/01/17 11:49:09 martin Exp $ */ /* * Copyright (c) 2005, 2006, 2007 Antti Kantee. All Rights Reserved. @@ -30,7 +30,7 @@ */ #include <sys/cdefs.h> -__KERNEL_RCSID(0, "$NetBSD: puffs_vnops.c,v 1.182.2.11 2014/11/09 10:09:32 msaitoh Exp $"); +__KERNEL_RCSID(0, "$NetBSD: puffs_vnops.c,v 1.182.2.12 2015/01/17 11:49:09 martin Exp $"); #include <sys/param.h> #include <sys/buf.h> @@ -2279,9 +2279,17 @@ puffs_vnop_read(void *v) if (uio->uio_offset < 0) return EFBIG; + /* + * On the case of reading empty files and (vp->v_size != 0) below: + * some filesystems (hint: FUSE and distributed filesystems) still + * expect to get the READ in order to update atime. Reading through + * the case filters empty files, therefore we prefer to bypass the + * cache here. + */ if (vp->v_type == VREG && PUFFS_USE_PAGECACHE(pmp) && - !(pn->pn_stat & PNODE_RDIRECT)) { + !(pn->pn_stat & PNODE_RDIRECT) && + (vp->v_size != 0)) { const int advice = IO_ADV_DECODE(ap->a_ioflag); while (uio->uio_resid > 0) {