From 857f11169fc8d7575b6b92e5dbb57b4c359d9dcc Mon Sep 17 00:00:00 2001 From: Mr NeilBrown Date: Wed, 18 Mar 2020 10:00:29 +1100 Subject: [PATCH] LU-13004 lnet: always put a page list into struct lnet_libmd 'struct lnet_libmd' is only created in lnet_md_build(). It can be given a list of pages or a virtual address. In the latter case, the memory will eventually be split into a list of pages. It is cleaner to split it into a list of pages early so that all lower levels only need to handle one type: a page list. Signed-off-by: Mr NeilBrown Change-Id: Iaeb4f18f7ac63986e6fed259945e8594ea1b9f25 Reviewed-on: https://review.whamcloud.com/37842 Reviewed-by: Shaun Tancheff Tested-by: jenkins Tested-by: Maloo Reviewed-by: James Simmons Reviewed-by: Oleg Drokin --- lnet/lnet/lib-md.c | 40 ++++++++++++++++++++++++++-------------- 1 file changed, 26 insertions(+), 14 deletions(-) diff --git a/lnet/lnet/lib-md.c b/lnet/lnet/lib-md.c index b46a290..8830820 100644 --- a/lnet/lnet/lib-md.c +++ b/lnet/lnet/lib-md.c @@ -191,13 +191,12 @@ lnet_md_build(struct lnet_md *umd, int unlink) struct lnet_libmd *lmd; unsigned int size; - if ((umd->options & LNET_MD_KIOV) != 0) { + if (umd->options & LNET_MD_KIOV) niov = umd->length; - size = offsetof(struct lnet_libmd, md_iov.kiov[niov]); - } else { - niov = 1; - size = offsetof(struct lnet_libmd, md_iov.iov[niov]); - } + else + niov = DIV_ROUND_UP(offset_in_page(umd->start) + umd->length, + PAGE_SIZE); + size = offsetof(struct lnet_libmd, md_iov.kiov[niov]); if (size <= LNET_SMALL_MD_SIZE) { lmd = kmem_cache_zalloc(lnet_small_mds_cachep, GFP_NOFS); @@ -218,7 +217,6 @@ lnet_md_build(struct lnet_md *umd, int unlink) lmd->md_niov = niov; INIT_LIST_HEAD(&lmd->md_list); - lmd->md_me = NULL; lmd->md_start = umd->start; lmd->md_offset = 0; @@ -231,8 +229,7 @@ lnet_md_build(struct lnet_md *umd, int unlink) lmd->md_flags = (unlink == LNET_UNLINK) ? LNET_MD_FLAG_AUTO_UNLINK : 0; lmd->md_bulk_handle = umd->bulk_handle; - if ((umd->options & LNET_MD_KIOV) != 0) { - lmd->md_niov = niov = umd->length; + if (umd->options & LNET_MD_KIOV) { memcpy(lmd->md_iov.kiov, umd->start, niov * sizeof(lmd->md_iov.kiov[0])); @@ -255,18 +252,33 @@ lnet_md_build(struct lnet_md *umd, int unlink) lnet_md_free(lmd); return ERR_PTR(-EINVAL); } - } else { /* contiguous */ - lmd->md_length = umd->length; - lmd->md_niov = niov = 1; - lmd->md_iov.iov[0].iov_base = umd->start; - lmd->md_iov.iov[0].iov_len = umd->length; + } else { /* contiguous - split into pages */ + void *pa = umd->start; + int len = umd->length; + lmd->md_length = len; + i = 0; + while (len) { + int plen; + + plen = min_t(int, len, PAGE_SIZE - offset_in_page(pa)); + + lmd->md_iov.kiov[i].bv_page = + lnet_kvaddr_to_page((unsigned long) pa); + lmd->md_iov.kiov[i].bv_offset = offset_in_page(pa); + lmd->md_iov.kiov[i].bv_len = plen; + + len -= plen; + pa += plen; + i += 1; + } if ((umd->options & LNET_MD_MAX_SIZE) && /* max size used */ (umd->max_size < 0 || umd->max_size > (int)umd->length)) { /* illegal max_size */ lnet_md_free(lmd); return ERR_PTR(-EINVAL); } + lmd->md_options |= LNET_MD_KIOV; } return lmd; -- 1.8.3.1