git: bd11dd6fb9a0 - stable/13 - fusefs: only test for incoherency if FN_SIZECHANGE is set

[Alan Somers]

The branch stable/13 has been updated by asomers:

URL: 
https://cgit.FreeBSD.org/src/commit/?id=bd11dd6fb9a0e4daa04f0fa66ed38d44f716e919

commit bd11dd6fb9a0e4daa04f0fa66ed38d44f716e919
Author:     Emil Tsalapatis <e...@etsalapatis.com>
AuthorDate: 2024-02-08 01:13:43 +0000
Commit:     Alan Somers <asom...@freebsd.org>
CommitDate: 2024-06-13 19:46:01 +0000

    fusefs: only test for incoherency if FN_SIZECHANGE is set
    
    FUSE emits spurious incoherency warnings in writethrough mode. The
    warnings are triggered by setattr calls generated by vnode truncation
    turning the cached va_size vattr stale, causing comparisons with the
    fresh version provided by the server to fail. Only validate the vnode's
    va_size vattr if the FN_SIZECHANGE flag is set.
    
    This is a part of the research work at RCSLab, University of Waterloo.
    
    Reviewed by:    asomers
    Pull Request:   https://github.com/freebsd/freebsd-src/pull/1110
    
    (cherry picked from commit 8758bf0aaec1d4b2ebcb429e8cabc691c2c95461)
---
 sys/fs/fuse/fuse_internal.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/sys/fs/fuse/fuse_internal.c b/sys/fs/fuse/fuse_internal.c
index c851cb2e34f4..adf84d30e801 100644
--- a/sys/fs/fuse/fuse_internal.c
+++ b/sys/fs/fuse/fuse_internal.c
@@ -270,10 +270,10 @@ fuse_internal_cache_attrs(struct vnode *vp, struct 
fuse_attr *attr,
 
        if (vnode_isreg(vp) &&
            fvdat->cached_attrs.va_size != VNOVAL &&
+           fvdat->flag & FN_SIZECHANGE &&
            attr->size != fvdat->cached_attrs.va_size)
        {
-               if ( data->cache_mode == FUSE_CACHE_WB &&
-                   fvdat->flag & FN_SIZECHANGE)
+               if (data->cache_mode == FUSE_CACHE_WB)
                {
                        const char *msg;