Kairui Song <ryncsn@xxxxxxxxx> writes:
> From: Kairui Song <kasong@xxxxxxxxxxx>
>
> folio_file_pos and page_file_offset are for mixed usage of swap cache
> and page cache, it can't be page cache here, so introduce a new helper
> to get the swap offset in swap device directly.
>
> Need to include swapops.h in mm/swap.h to ensure swp_offset is always
> defined before use.
>
> Signed-off-by: Kairui Song <kasong@xxxxxxxxxxx>
LGTM! Thanks!
Reviewed-by: "Huang, Ying" <ying.huang@xxxxxxxxx>
> ---
> mm/page_io.c | 6 +++---
> mm/swap.h | 9 +++++++++
> 2 files changed, 12 insertions(+), 3 deletions(-)
>
> diff --git a/mm/page_io.c b/mm/page_io.c
> index 46c603dddf04..a360857cf75d 100644
> --- a/mm/page_io.c
> +++ b/mm/page_io.c
> @@ -280,7 +280,7 @@ static void sio_write_complete(struct kiocb *iocb, long ret)
> * be temporary.
> */
> pr_err_ratelimited("Write error %ld on dio swapfile (%llu)\n",
> - ret, page_file_offset(page));
> + ret, swap_dev_pos(page_swap_entry(page)));
> for (p = 0; p < sio->pages; p++) {
> page = sio->bvec[p].bv_page;
> set_page_dirty(page);
> @@ -299,7 +299,7 @@ static void swap_writepage_fs(struct folio *folio, struct writeback_control *wbc
> struct swap_iocb *sio = NULL;
> struct swap_info_struct *sis = swp_swap_info(folio->swap);
> struct file *swap_file = sis->swap_file;
> - loff_t pos = folio_file_pos(folio);
> + loff_t pos = swap_dev_pos(folio->swap);
>
> count_swpout_vm_event(folio);
> folio_start_writeback(folio);
> @@ -430,7 +430,7 @@ static void swap_read_folio_fs(struct folio *folio, struct swap_iocb **plug)
> {
> struct swap_info_struct *sis = swp_swap_info(folio->swap);
> struct swap_iocb *sio = NULL;
> - loff_t pos = folio_file_pos(folio);
> + loff_t pos = swap_dev_pos(folio->swap);
>
> if (plug)
> sio = *plug;
> diff --git a/mm/swap.h b/mm/swap.h
> index fc2f6ade7f80..82023ab93205 100644
> --- a/mm/swap.h
> +++ b/mm/swap.h
> @@ -5,6 +5,7 @@
> struct mempolicy;
>
> #ifdef CONFIG_SWAP
> +#include <linux/swapops.h> /* for swp_offset */
> #include <linux/blk_types.h> /* for bio_end_io_t */
>
> /* linux/mm/page_io.c */
> @@ -31,6 +32,14 @@ extern struct address_space *swapper_spaces[];
> (&swapper_spaces[swp_type(entry)][swp_offset(entry) \
> >> SWAP_ADDRESS_SPACE_SHIFT])
>
> +/*
> + * Return the swap device position of the swap entry.
> + */
> +static inline loff_t swap_dev_pos(swp_entry_t entry)
> +{
> + return ((loff_t)swp_offset(entry)) << PAGE_SHIFT;
> +}
> +
> void show_swap_cache_info(void);
> bool add_to_swap(struct folio *folio);
> void *get_shadow_from_swap_cache(swp_entry_t entry);
