diff options
Diffstat (limited to 'mm/readahead.c')
| -rw-r--r-- | mm/readahead.c | 49 |
1 files changed, 29 insertions, 20 deletions
diff --git a/mm/readahead.c b/mm/readahead.c index e151f4b13ca4..6a4e96b69702 100644 --- a/mm/readahead.c +++ b/mm/readahead.c @@ -158,20 +158,10 @@ static void read_pages(struct readahead_control *rac) if (aops->readahead) { aops->readahead(rac); - /* - * Clean up the remaining folios. The sizes in ->ra - * may be used to size the next readahead, so make sure - * they accurately reflect what happened. - */ + /* Clean up the remaining folios. */ while ((folio = readahead_folio(rac)) != NULL) { - unsigned long nr = folio_nr_pages(folio); - folio_get(folio); - rac->ra->size -= nr; - if (rac->ra->async_size >= nr) { - rac->ra->async_size -= nr; - filemap_remove_folio(folio); - } + filemap_remove_folio(folio); folio_unlock(folio); folio_put(folio); } @@ -188,6 +178,18 @@ static void read_pages(struct readahead_control *rac) BUG_ON(readahead_count(rac)); } +static struct folio *ractl_alloc_folio(struct readahead_control *ractl, + gfp_t gfp_mask, unsigned int order) +{ + struct folio *folio; + + folio = filemap_alloc_folio(gfp_mask, order); + if (folio && ractl->dropbehind) + __folio_set_dropbehind(folio); + + return folio; +} + /** * page_cache_ra_unbounded - Start unchecked readahead. * @ractl: Readahead control. @@ -265,8 +267,8 @@ void page_cache_ra_unbounded(struct readahead_control *ractl, continue; } - folio = filemap_alloc_folio(gfp_mask, - mapping_min_folio_order(mapping)); + folio = ractl_alloc_folio(ractl, gfp_mask, + mapping_min_folio_order(mapping)); if (!folio) break; @@ -436,7 +438,7 @@ static inline int ra_alloc_folio(struct readahead_control *ractl, pgoff_t index, pgoff_t mark, unsigned int order, gfp_t gfp) { int err; - struct folio *folio = filemap_alloc_folio(gfp, order); + struct folio *folio = ractl_alloc_folio(ractl, gfp, order); if (!folio) return -ENOMEM; @@ -458,7 +460,8 @@ void page_cache_ra_order(struct readahead_control *ractl, struct file_ra_state *ra, unsigned int new_order) { struct address_space *mapping = ractl->mapping; - pgoff_t index = readahead_index(ractl); + pgoff_t start = readahead_index(ractl); + pgoff_t index = start; unsigned int min_order = mapping_min_folio_order(mapping); pgoff_t limit = (i_size_read(mapping->host) - 1) >> PAGE_SHIFT; pgoff_t mark = index + ra->size - ra->async_size; @@ -516,12 +519,18 @@ void page_cache_ra_order(struct readahead_control *ractl, /* * If there were already pages in the page cache, then we may have * left some gaps. Let the regular readahead code take care of this - * situation. + * situation below. */ if (!err) return; fallback: - do_page_cache_ra(ractl, ra->size, ra->async_size); + /* + * ->readahead() may have updated readahead window size so we have to + * check there's still something to read. + */ + if (ra->size > index - start) + do_page_cache_ra(ractl, ra->size - (index - start), + ra->async_size); } static unsigned long ractl_max_pages(struct readahead_control *ractl, @@ -754,7 +763,7 @@ void readahead_expand(struct readahead_control *ractl, if (folio && !xa_is_value(folio)) return; /* Folio apparently present */ - folio = filemap_alloc_folio(gfp_mask, min_order); + folio = ractl_alloc_folio(ractl, gfp_mask, min_order); if (!folio) return; @@ -783,7 +792,7 @@ void readahead_expand(struct readahead_control *ractl, if (folio && !xa_is_value(folio)) return; /* Folio apparently present */ - folio = filemap_alloc_folio(gfp_mask, min_order); + folio = ractl_alloc_folio(ractl, gfp_mask, min_order); if (!folio) return; |