| Message ID | 1384327335-18812-1-git-send-email-liwang@ubuntukylin.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Wed, Nov 13, 2013 at 3:22 PM, Li Wang <liwang@ubuntukylin.com> wrote: > If the length of data to be read in readpage() is exactly > PAGE_CACHE_SIZE, the original code does not flush d-cache > for data consistency after finishing reading. This patches fixes > this. > > Signed-off-by: Li Wang <liwang@ubuntukylin.com> > --- > fs/ceph/addr.c | 8 ++++++-- > 1 file changed, 6 insertions(+), 2 deletions(-) > > diff --git a/fs/ceph/addr.c b/fs/ceph/addr.c > index 6df8bd4..7b0000a 100644 > --- a/fs/ceph/addr.c > +++ b/fs/ceph/addr.c > @@ -210,9 +210,13 @@ static int readpage_nounlock(struct file *filp, struct page *page) > if (err < 0) { > SetPageError(page); > goto out; > - } else if (err < PAGE_CACHE_SIZE) { > + } else { > + if (err < PAGE_CACHE_SIZE) { > /* zero fill remainder of page */ > - zero_user_segment(page, err, PAGE_CACHE_SIZE); > + zero_user_segment(page, err, PAGE_CACHE_SIZE); > + } else { > + flush_dcache_page(page); > + } this doesn't make sense for me. why not call flush_dcache_page unconditionally? Regards Yan, Zheng > } > SetPageUptodate(page); > > -- > 1.7.9.5 > > -- > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > Please read the FAQ at http://www.tux.org/lkml/ -- To unsubscribe from this list: send the line "unsubscribe ceph-devel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Hi Yan, zero_user_segment() has invoked flush_dcache_page() for us, we donnot wanna flush d-cache twice. Cheers, Li Wang On 11/13/2013 09:19 PM, Yan, Zheng wrote: > On Wed, Nov 13, 2013 at 3:22 PM, Li Wang <liwang@ubuntukylin.com> wrote: >> If the length of data to be read in readpage() is exactly >> PAGE_CACHE_SIZE, the original code does not flush d-cache >> for data consistency after finishing reading. This patches fixes >> this. >> >> Signed-off-by: Li Wang <liwang@ubuntukylin.com> >> --- >> fs/ceph/addr.c | 8 ++++++-- >> 1 file changed, 6 insertions(+), 2 deletions(-) >> >> diff --git a/fs/ceph/addr.c b/fs/ceph/addr.c >> index 6df8bd4..7b0000a 100644 >> --- a/fs/ceph/addr.c >> +++ b/fs/ceph/addr.c >> @@ -210,9 +210,13 @@ static int readpage_nounlock(struct file *filp, struct page *page) >> if (err < 0) { >> SetPageError(page); >> goto out; >> - } else if (err < PAGE_CACHE_SIZE) { >> + } else { >> + if (err < PAGE_CACHE_SIZE) { >> /* zero fill remainder of page */ >> - zero_user_segment(page, err, PAGE_CACHE_SIZE); >> + zero_user_segment(page, err, PAGE_CACHE_SIZE); >> + } else { >> + flush_dcache_page(page); >> + } > > this doesn't make sense for me. why not call flush_dcache_page unconditionally? > > Regards > Yan, Zheng >> } >> SetPageUptodate(page); >> >> -- >> 1.7.9.5 >> >> -- >> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in >> the body of a message to majordomo@vger.kernel.org >> More majordomo info at http://vger.kernel.org/majordomo-info.html >> Please read the FAQ at http://www.tux.org/lkml/ > -- To unsubscribe from this list: send the line "unsubscribe ceph-devel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/fs/ceph/addr.c b/fs/ceph/addr.c index 6df8bd4..7b0000a 100644 --- a/fs/ceph/addr.c +++ b/fs/ceph/addr.c @@ -210,9 +210,13 @@ static int readpage_nounlock(struct file *filp, struct page *page) if (err < 0) { SetPageError(page); goto out; - } else if (err < PAGE_CACHE_SIZE) { + } else { + if (err < PAGE_CACHE_SIZE) { /* zero fill remainder of page */ - zero_user_segment(page, err, PAGE_CACHE_SIZE); + zero_user_segment(page, err, PAGE_CACHE_SIZE); + } else { + flush_dcache_page(page); + } } SetPageUptodate(page);
If the length of data to be read in readpage() is exactly PAGE_CACHE_SIZE, the original code does not flush d-cache for data consistency after finishing reading. This patches fixes this. Signed-off-by: Li Wang <liwang@ubuntukylin.com> --- fs/ceph/addr.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-)