diff options
Diffstat (limited to 'lib')
| -rw-r--r-- | lib/scatterlist.c | 32 |
1 files changed, 27 insertions, 5 deletions
diff --git a/lib/scatterlist.c b/lib/scatterlist.c index 9afc9b432083..53728d391d3a 100644 --- a/lib/scatterlist.c +++ b/lib/scatterlist.c @@ -512,7 +512,7 @@ struct scatterlist *sgl_alloc_order(unsigned long long length, if (!sgl) return NULL; - sg_init_table(sgl, nent); + sg_init_table(sgl, nalloc); sg = sgl; while (length) { elem_len = min_t(u64, length, PAGE_SIZE << order); @@ -526,7 +526,7 @@ struct scatterlist *sgl_alloc_order(unsigned long long length, length -= elem_len; sg = sg_next(sg); } - WARN_ON_ONCE(sg); + WARN_ONCE(length, "length = %lld\n", length); if (nent_p) *nent_p = nent; return sgl; @@ -549,22 +549,44 @@ struct scatterlist *sgl_alloc(unsigned long long length, gfp_t gfp, EXPORT_SYMBOL(sgl_alloc); /** - * sgl_free_order - free a scatterlist and its pages + * sgl_free_n_order - free a scatterlist and its pages * @sgl: Scatterlist with one or more elements + * @nents: Maximum number of elements to free * @order: Second argument for __free_pages() + * + * Notes: + * - If several scatterlists have been chained and each chain element is + * freed separately then it's essential to set nents correctly to avoid that a + * page would get freed twice. + * - All pages in a chained scatterlist can be freed at once by setting @nents + * to a high number. */ -void sgl_free_order(struct scatterlist *sgl, int order) +void sgl_free_n_order(struct scatterlist *sgl, int nents, int order) { struct scatterlist *sg; struct page *page; + int i; - for (sg = sgl; sg; sg = sg_next(sg)) { + for_each_sg(sgl, sg, nents, i) { + if (!sg) + break; page = sg_page(sg); if (page) __free_pages(page, order); } kfree(sgl); } +EXPORT_SYMBOL(sgl_free_n_order); + +/** + * sgl_free_order - free a scatterlist and its pages + * @sgl: Scatterlist with one or more elements + * @order: Second argument for __free_pages() + */ +void sgl_free_order(struct scatterlist *sgl, int order) +{ + sgl_free_n_order(sgl, INT_MAX, order); +} EXPORT_SYMBOL(sgl_free_order); /** |