From: Keqian Zhu <zhukeqian1@huawei.com>
To: <linux-kernel@vger.kernel.org>,
<linux-arm-kernel@lists.infradead.org>,
<iommu@lists.linux-foundation.org>, <kvm@vger.kernel.org>,
<kvmarm@lists.cs.columbia.edu>,
Alex Williamson <alex.williamson@redhat.com>,
Kirti Wankhede <kwankhede@nvidia.com>,
Cornelia Huck <cohuck@redhat.com>, Will Deacon <will@kernel.org>,
Marc Zyngier <maz@kernel.org>,
Catalin Marinas <catalin.marinas@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>,
James Morse <james.morse@arm.com>,
Robin Murphy <robin.murphy@arm.com>,
Joerg Roedel <joro@8bytes.org>,
"Daniel Lezcano" <daniel.lezcano@linaro.org>,
Thomas Gleixner <tglx@linutronix.de>,
Suzuki K Poulose <suzuki.poulose@arm.com>,
Julien Thierry <julien.thierry.kdev@gmail.com>,
Andrew Morton <akpm@linux-foundation.org>,
Alexios Zavras <alexios.zavras@intel.com>,
<wanghaibin.wang@huawei.com>, <jiangkunkun@huawei.com>
Subject: [PATCH 1/5] vfio/iommu_type1: Fixes vfio_dma_populate_bitmap to avoid dirty lose
Date: Thu, 7 Jan 2021 17:28:57 +0800 [thread overview]
Message-ID: <20210107092901.19712-2-zhukeqian1@huawei.com> (raw)
In-Reply-To: <20210107092901.19712-1-zhukeqian1@huawei.com>
Defer checking whether vfio_dma is of fully-dirty in update_user_bitmap
is easy to lose dirty log. For example, after promoting pinned_scope of
vfio_iommu, vfio_dma is not considered as fully-dirty, then we may lose
dirty log that occurs before vfio_iommu is promoted.
The key point is that pinned-dirty is not a real dirty tracking way, it
can't continuously track dirty pages, but just restrict dirty scope. It
is essentially the same as fully-dirty. Fully-dirty is of full-scope and
pinned-dirty is of pinned-scope.
So we must mark pinned-dirty or fully-dirty after we start dirty tracking
or clear dirty bitmap, to ensure that dirty log is marked right away.
Fixes: d6a4c185660c ("vfio iommu: Implementation of ioctl for dirty pages tracking")
Signed-off-by: Keqian Zhu <zhukeqian1@huawei.com>
---
drivers/vfio/vfio_iommu_type1.c | 33 ++++++++++++++++++++++-----------
1 file changed, 22 insertions(+), 11 deletions(-)
diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c
index bceda5e8baaa..b0a26e8e0adf 100644
--- a/drivers/vfio/vfio_iommu_type1.c
+++ b/drivers/vfio/vfio_iommu_type1.c
@@ -224,7 +224,7 @@ static void vfio_dma_bitmap_free(struct vfio_dma *dma)
dma->bitmap = NULL;
}
-static void vfio_dma_populate_bitmap(struct vfio_dma *dma, size_t pgsize)
+static void vfio_dma_populate_bitmap_pinned(struct vfio_dma *dma, size_t pgsize)
{
struct rb_node *p;
unsigned long pgshift = __ffs(pgsize);
@@ -236,6 +236,25 @@ static void vfio_dma_populate_bitmap(struct vfio_dma *dma, size_t pgsize)
}
}
+static void vfio_dma_populate_bitmap_full(struct vfio_dma *dma, size_t pgsize)
+{
+ unsigned long pgshift = __ffs(pgsize);
+ unsigned long nbits = dma->size >> pgshift;
+
+ bitmap_set(dma->bitmap, 0, nbits);
+}
+
+static void vfio_dma_populate_bitmap(struct vfio_iommu *iommu,
+ struct vfio_dma *dma)
+{
+ size_t pgsize = (size_t)1 << __ffs(iommu->pgsize_bitmap);
+
+ if (iommu->pinned_page_dirty_scope)
+ vfio_dma_populate_bitmap_pinned(dma, pgsize);
+ else if (dma->iommu_mapped)
+ vfio_dma_populate_bitmap_full(dma, pgsize);
+}
+
static int vfio_dma_bitmap_alloc_all(struct vfio_iommu *iommu)
{
struct rb_node *n;
@@ -257,7 +276,7 @@ static int vfio_dma_bitmap_alloc_all(struct vfio_iommu *iommu)
}
return ret;
}
- vfio_dma_populate_bitmap(dma, pgsize);
+ vfio_dma_populate_bitmap(iommu, dma);
}
return 0;
}
@@ -987,13 +1006,6 @@ static int update_user_bitmap(u64 __user *bitmap, struct vfio_iommu *iommu,
unsigned long shift = bit_offset % BITS_PER_LONG;
unsigned long leftover;
- /*
- * mark all pages dirty if any IOMMU capable device is not able
- * to report dirty pages and all pages are pinned and mapped.
- */
- if (!iommu->pinned_page_dirty_scope && dma->iommu_mapped)
- bitmap_set(dma->bitmap, 0, nbits);
-
if (shift) {
bitmap_shift_left(dma->bitmap, dma->bitmap, shift,
nbits + shift);
@@ -1019,7 +1031,6 @@ static int vfio_iova_dirty_bitmap(u64 __user *bitmap, struct vfio_iommu *iommu,
struct vfio_dma *dma;
struct rb_node *n;
unsigned long pgshift = __ffs(iommu->pgsize_bitmap);
- size_t pgsize = (size_t)1 << pgshift;
int ret;
/*
@@ -1055,7 +1066,7 @@ static int vfio_iova_dirty_bitmap(u64 __user *bitmap, struct vfio_iommu *iommu,
* pages which are marked dirty by vfio_dma_rw()
*/
bitmap_clear(dma->bitmap, 0, dma->size >> pgshift);
- vfio_dma_populate_bitmap(dma, pgsize);
+ vfio_dma_populate_bitmap(iommu, dma);
}
return 0;
}
--
2.19.1
next prev parent reply other threads:[~2021-01-07 9:30 UTC|newest]
Thread overview: 16+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-01-07 9:28 [PATCH 0/5] vfio/iommu_type1: Some fixes about dirty tracking Keqian Zhu
2021-01-07 9:28 ` Keqian Zhu [this message]
2021-01-12 21:20 ` [PATCH 1/5] vfio/iommu_type1: Fixes vfio_dma_populate_bitmap to avoid dirty lose Alex Williamson
2021-01-13 12:35 ` Kirti Wankhede
2021-01-13 15:13 ` Alex Williamson
2021-01-14 13:05 ` Keqian Zhu
2021-01-14 17:14 ` Alex Williamson
2021-01-15 9:41 ` Keqian Zhu
2021-01-07 9:28 ` [PATCH 2/5] vfio/iommu_type1: Populate dirty bitmap for new vfio_dma Keqian Zhu
2021-01-07 9:28 ` [PATCH 3/5] vfio/iommu_type1: Populate dirty bitmap when attach group Keqian Zhu
2021-01-07 9:29 ` [PATCH 4/5] vfio/iommu_type1: Carefully use unmap_unpin_all during dirty tracking Keqian Zhu
2021-01-11 21:49 ` Alex Williamson
2021-01-12 12:04 ` Keqian Zhu
2021-01-12 19:53 ` Alex Williamson
2021-01-14 12:11 ` Keqian Zhu
2021-01-07 9:29 ` [PATCH 5/5] vfio/iommu_type1: Move sanity_check_pfn_list to unmap_unpin_all Keqian Zhu
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20210107092901.19712-2-zhukeqian1@huawei.com \
--to=zhukeqian1@huawei.com \
--cc=akpm@linux-foundation.org \
--cc=alex.williamson@redhat.com \
--cc=alexios.zavras@intel.com \
--cc=catalin.marinas@arm.com \
--cc=cohuck@redhat.com \
--cc=daniel.lezcano@linaro.org \
--cc=iommu@lists.linux-foundation.org \
--cc=james.morse@arm.com \
--cc=jiangkunkun@huawei.com \
--cc=joro@8bytes.org \
--cc=julien.thierry.kdev@gmail.com \
--cc=kvm@vger.kernel.org \
--cc=kvmarm@lists.cs.columbia.edu \
--cc=kwankhede@nvidia.com \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux-kernel@vger.kernel.org \
--cc=mark.rutland@arm.com \
--cc=maz@kernel.org \
--cc=robin.murphy@arm.com \
--cc=suzuki.poulose@arm.com \
--cc=tglx@linutronix.de \
--cc=wanghaibin.wang@huawei.com \
--cc=will@kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).