| Message ID | 20230915183848.1018717-6-kernel@pankajraghav.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | Enable block size > page size in XFS | expand |
On Fri, Sep 15, 2023 at 08:38:30PM +0200, Pankaj Raghav wrote: > From: Luis Chamberlain <mcgrof@kernel.org> > > page cache is mapping min_folio_order aligned. Use mapping min_folio_order > to align the start_byte and end_byte in filemap_range_has_page(). What goes wrong if you don't? Seems to me like it should work. > Signed-off-by: Luis Chamberlain <mcgrof@kernel.org> > --- > mm/filemap.c | 7 +++++-- > 1 file changed, 5 insertions(+), 2 deletions(-) > > diff --git a/mm/filemap.c b/mm/filemap.c > index 2c47729dc8b0..4dee24b5b61c 100644 > --- a/mm/filemap.c > +++ b/mm/filemap.c > @@ -477,9 +477,12 @@ EXPORT_SYMBOL(filemap_flush); > bool filemap_range_has_page(struct address_space *mapping, > loff_t start_byte, loff_t end_byte) > { > + unsigned int min_order = mapping_min_folio_order(mapping); > + unsigned int nrpages = 1UL << min_order; > + pgoff_t index = round_down(start_byte >> PAGE_SHIFT, nrpages); > struct folio *folio; > - XA_STATE(xas, &mapping->i_pages, start_byte >> PAGE_SHIFT); > - pgoff_t max = end_byte >> PAGE_SHIFT; > + XA_STATE(xas, &mapping->i_pages, index); > + pgoff_t max = round_down(end_byte >> PAGE_SHIFT, nrpages); > > if (end_byte < start_byte) > return false; > -- > 2.40.1 >
On Fri, Sep 15, 2023 at 08:45:20PM +0100, Matthew Wilcox wrote: > On Fri, Sep 15, 2023 at 08:38:30PM +0200, Pankaj Raghav wrote: > > From: Luis Chamberlain <mcgrof@kernel.org> > > > > page cache is mapping min_folio_order aligned. Use mapping min_folio_order > > to align the start_byte and end_byte in filemap_range_has_page(). > > What goes wrong if you don't? Seems to me like it should work. Will drop from the series after confirming, thanks. Luis
diff --git a/mm/filemap.c b/mm/filemap.c index 2c47729dc8b0..4dee24b5b61c 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -477,9 +477,12 @@ EXPORT_SYMBOL(filemap_flush); bool filemap_range_has_page(struct address_space *mapping, loff_t start_byte, loff_t end_byte) { + unsigned int min_order = mapping_min_folio_order(mapping); + unsigned int nrpages = 1UL << min_order; + pgoff_t index = round_down(start_byte >> PAGE_SHIFT, nrpages); struct folio *folio; - XA_STATE(xas, &mapping->i_pages, start_byte >> PAGE_SHIFT); - pgoff_t max = end_byte >> PAGE_SHIFT; + XA_STATE(xas, &mapping->i_pages, index); + pgoff_t max = round_down(end_byte >> PAGE_SHIFT, nrpages); if (end_byte < start_byte) return false;