lists.openwall.net   lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  linux-hardening  linux-cve-announce  PHC 
Open Source and information security mailing list archives
 
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Date:	Thu, 13 Aug 2015 15:15:23 -0400
From:	Jérôme Glisse <jglisse@...hat.com>
To:	akpm@...ux-foundation.org, <linux-kernel@...r.kernel.org>,
	linux-mm@...ck.org
Cc:	Linus Torvalds <torvalds@...ux-foundation.org>, <joro@...tes.org>,
	Mel Gorman <mgorman@...e.de>, "H. Peter Anvin" <hpa@...or.com>,
	Peter Zijlstra <peterz@...radead.org>,
	Andrea Arcangeli <aarcange@...hat.com>,
	Johannes Weiner <jweiner@...hat.com>,
	Larry Woodman <lwoodman@...hat.com>,
	Rik van Riel <riel@...hat.com>,
	Dave Airlie <airlied@...hat.com>,
	Brendan Conoboy <blc@...hat.com>,
	Joe Donohue <jdonohue@...hat.com>,
	Christophe Harle <charle@...dia.com>,
	Duncan Poole <dpoole@...dia.com>,
	Sherry Cheung <SCheung@...dia.com>,
	Subhash Gutti <sgutti@...dia.com>,
	John Hubbard <jhubbard@...dia.com>,
	Mark Hairgrove <mhairgrove@...dia.com>,
	Lucien Dunning <ldunning@...dia.com>,
	Cameron Buschardt <cabuschardt@...dia.com>,
	Arvind Gopalakrishnan <arvindg@...dia.com>,
	Haggai Eran <haggaie@...lanox.com>,
	Shachar Raindel <raindel@...lanox.com>,
	Liran Liss <liranl@...lanox.com>,
	Roland Dreier <roland@...estorage.com>,
	Ben Sander <ben.sander@....com>,
	Greg Stoner <Greg.Stoner@....com>,
	John Bridgman <John.Bridgman@....com>,
	Michael Mantor <Michael.Mantor@....com>,
	Paul Blinzer <Paul.Blinzer@....com>,
	Leonid Shamis <Leonid.Shamis@....com>,
	Laurent Morichetti <Laurent.Morichetti@....com>,
	Alexander Deucher <Alexander.Deucher@....com>,
	Jerome Glisse <jglisse@...hat.com>
Subject: [PATCH 10/15] HMM: use CPU page table during invalidation.

From: Jerome Glisse <jglisse@...hat.com>

Once we store the dma mapping inside the secondary page table we can
no longer easily find back the page backing an address. Instead use
the cpu page table which still has the proper information, except for
the invalidate_page() case which is handled by using the page passed
by the mmu_notifier layer.

Signed-off-by: Jérôme Glisse <jglisse@...hat.com>
---
 mm/hmm.c | 53 +++++++++++++++++++++++++++++++++++------------------
 1 file changed, 35 insertions(+), 18 deletions(-)

diff --git a/mm/hmm.c b/mm/hmm.c
index f0c3c81..d652233 100644
--- a/mm/hmm.c
+++ b/mm/hmm.c
@@ -47,9 +47,11 @@
 static struct mmu_notifier_ops hmm_notifier_ops;
 static void hmm_mirror_kill(struct hmm_mirror *mirror);
 static inline int hmm_mirror_update(struct hmm_mirror *mirror,
-				    struct hmm_event *event);
+				    struct hmm_event *event,
+				    struct page *page);
 static void hmm_mirror_update_pt(struct hmm_mirror *mirror,
-				 struct hmm_event *event);
+				 struct hmm_event *event,
+				 struct page *page);
 
 
 /* hmm_event - use to track information relating to an event.
@@ -223,7 +225,9 @@ again:
 	}
 }
 
-static void hmm_update(struct hmm *hmm, struct hmm_event *event)
+static void hmm_update(struct hmm *hmm,
+		       struct hmm_event *event,
+		       struct page *page)
 {
 	struct hmm_mirror *mirror;
 
@@ -236,7 +240,7 @@ static void hmm_update(struct hmm *hmm, struct hmm_event *event)
 again:
 	down_read(&hmm->rwsem);
 	hlist_for_each_entry(mirror, &hmm->mirrors, mlist)
-		if (hmm_mirror_update(mirror, event)) {
+		if (hmm_mirror_update(mirror, event, page)) {
 			mirror = hmm_mirror_ref(mirror);
 			up_read(&hmm->rwsem);
 			hmm_mirror_kill(mirror);
@@ -304,7 +308,7 @@ static void hmm_notifier_release(struct mmu_notifier *mn, struct mm_struct *mm)
 
 		/* Make sure everything is unmapped. */
 		hmm_event_init(&event, mirror->hmm, 0, -1UL, HMM_MUNMAP);
-		hmm_mirror_update(mirror, &event);
+		hmm_mirror_update(mirror, &event, NULL);
 
 		mirror->device->ops->release(mirror);
 		hmm_mirror_unref(&mirror);
@@ -338,9 +342,10 @@ static void hmm_mmu_mprot_to_etype(struct mm_struct *mm,
 	*etype = HMM_NONE;
 }
 
-static void hmm_notifier_invalidate_range_start(struct mmu_notifier *mn,
-					struct mm_struct *mm,
-					const struct mmu_notifier_range *range)
+static void hmm_notifier_invalidate(struct mmu_notifier *mn,
+				    struct mm_struct *mm,
+				    struct page *page,
+				    const struct mmu_notifier_range *range)
 {
 	struct hmm_event event;
 	unsigned long start = range->start, end = range->end;
@@ -379,7 +384,14 @@ static void hmm_notifier_invalidate_range_start(struct mmu_notifier *mn,
 
 	hmm_event_init(&event, hmm, start, end, event.etype);
 
-	hmm_update(hmm, &event);
+	hmm_update(hmm, &event, page);
+}
+
+static void hmm_notifier_invalidate_range_start(struct mmu_notifier *mn,
+					struct mm_struct *mm,
+					const struct mmu_notifier_range *range)
+{
+	hmm_notifier_invalidate(mn, mm, NULL, range);
 }
 
 static void hmm_notifier_invalidate_page(struct mmu_notifier *mn,
@@ -393,7 +405,7 @@ static void hmm_notifier_invalidate_page(struct mmu_notifier *mn,
 	range.start = addr & PAGE_MASK;
 	range.end = range.start + PAGE_SIZE;
 	range.event = mmu_event;
-	hmm_notifier_invalidate_range_start(mn, mm, &range);
+	hmm_notifier_invalidate(mn, mm, page, &range);
 }
 
 static struct mmu_notifier_ops hmm_notifier_ops = {
@@ -545,23 +557,27 @@ void hmm_mirror_unref(struct hmm_mirror **mirror)
 EXPORT_SYMBOL(hmm_mirror_unref);
 
 static inline int hmm_mirror_update(struct hmm_mirror *mirror,
-				    struct hmm_event *event)
+				    struct hmm_event *event,
+				    struct page *page)
 {
 	struct hmm_device *device = mirror->device;
 	int ret = 0;
 
 	ret = device->ops->update(mirror, event);
-	hmm_mirror_update_pt(mirror, event);
+	hmm_mirror_update_pt(mirror, event, page);
 	return ret;
 }
 
 static void hmm_mirror_update_pt(struct hmm_mirror *mirror,
-				 struct hmm_event *event)
+				 struct hmm_event *event,
+				 struct page *page)
 {
 	unsigned long addr;
 	struct hmm_pt_iter iter;
+	struct mm_pt_iter mm_iter;
 
 	hmm_pt_iter_init(&iter, &mirror->pt);
+	mm_pt_iter_init(&mm_iter, mirror->hmm->mm);
 	for (addr = event->start; addr != event->end;) {
 		unsigned long next = event->end;
 		dma_addr_t *hmm_pte;
@@ -582,10 +598,10 @@ static void hmm_mirror_update_pt(struct hmm_mirror *mirror,
 				continue;
 			if (hmm_pte_test_and_clear_dirty(hmm_pte) &&
 			    hmm_pte_test_write(hmm_pte)) {
-				struct page *page;
-
-				page = pfn_to_page(hmm_pte_pfn(*hmm_pte));
-				set_page_dirty(page);
+				page = page ? : mm_pt_iter_page(&mm_iter, addr);
+				if (page)
+					set_page_dirty(page);
+				page = NULL;
 			}
 			*hmm_pte &= event->pte_mask;
 			if (hmm_pte_test_valid_pfn(hmm_pte))
@@ -595,6 +611,7 @@ static void hmm_mirror_update_pt(struct hmm_mirror *mirror,
 		hmm_pt_iter_directory_unlock(&iter);
 	}
 	hmm_pt_iter_fini(&iter);
+	mm_pt_iter_fini(&mm_iter);
 }
 
 static inline bool hmm_mirror_is_dead(struct hmm_mirror *mirror)
@@ -979,7 +996,7 @@ static void hmm_mirror_kill(struct hmm_mirror *mirror)
 
 		/* Make sure everything is unmapped. */
 		hmm_event_init(&event, mirror->hmm, 0, -1UL, HMM_MUNMAP);
-		hmm_mirror_update(mirror, &event);
+		hmm_mirror_update(mirror, &event, NULL);
 
 		device->ops->release(mirror);
 		hmm_mirror_unref(&mirror);
-- 
1.9.3

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Powered by blists - more mailing lists

Powered by Openwall GNU/*/Linux Powered by OpenVZ