| Message ID | 20180620221503.25237-2-ross.zwisler@linux.intel.com |
|---|---|
| State | Superseded, archived |
| Headers | show |
| Series | ext4: fix DAX dma vs truncate/hole-punch | expand |
On Wed 20-06-18 16:15:02, Ross Zwisler wrote: > Inodes using DAX should only ever have exceptional entries in their page > caches. Make this clear by warning if the iteration in > dax_layout_busy_page() ever sees a non-exceptional entry, and by adding a > comment for the pagevec_release() call which only deals with struct page > pointers. > > Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com> > --- > fs/dax.c | 9 ++++++++- > 1 file changed, 8 insertions(+), 1 deletion(-) > > diff --git a/fs/dax.c b/fs/dax.c > index 641192808bb6..4a5e31f8a2d4 100644 > --- a/fs/dax.c > +++ b/fs/dax.c > @@ -566,7 +566,7 @@ struct page *dax_layout_busy_page(struct address_space *mapping) > if (index >= end) > break; > > - if (!radix_tree_exceptional_entry(pvec_ent)) > + if (WARN_ON_ONCE(!radix_tree_exceptional_entry(pvec_ent))) Please wrap this line. Otherwise the patch looks good. You can add: Reviewed-by: Jan Kara <jack@suse.cz> Honza
diff --git a/fs/dax.c b/fs/dax.c index 641192808bb6..4a5e31f8a2d4 100644 --- a/fs/dax.c +++ b/fs/dax.c @@ -566,7 +566,7 @@ struct page *dax_layout_busy_page(struct address_space *mapping) if (index >= end) break; - if (!radix_tree_exceptional_entry(pvec_ent)) + if (WARN_ON_ONCE(!radix_tree_exceptional_entry(pvec_ent))) continue; xa_lock_irq(&mapping->i_pages); @@ -578,6 +578,13 @@ struct page *dax_layout_busy_page(struct address_space *mapping) if (page) break; } + + /* + * We don't expect normal struct page entries to exist in our + * tree, but we keep these pagevec calls so that this code is + * consistent with the common pattern for handling pagevecs + * throughout the kernel. + */ pagevec_remove_exceptionals(&pvec); pagevec_release(&pvec); index++;
Inodes using DAX should only ever have exceptional entries in their page caches. Make this clear by warning if the iteration in dax_layout_busy_page() ever sees a non-exceptional entry, and by adding a comment for the pagevec_release() call which only deals with struct page pointers. Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com> --- fs/dax.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-)