From: Andrei Dulea via iommu <iommu@lists.linux-foundation.org>
To: Joerg Roedel <joro@8bytes.org>
Cc: iommu@lists.linux-foundation.org,
"Jan H. Schönherr" <jschoenh@amazon.de>,
"Andrei Dulea" <adulea@amazon.de>
Subject: [PATCH 3/4] iommu/amd: Introduce first_pte_l7() helper
Date: Fri, 13 Sep 2019 16:42:30 +0200 [thread overview]
Message-ID: <20190913144231.21382-4-adulea@amazon.de> (raw)
In-Reply-To: <20190913144231.21382-1-adulea@amazon.de>
Given an arbitrary pte that is part of a large mapping, this function
returns the first pte of the series (and optionally the mapped size and
number of PTEs)
It will be re-used in a subsequent patch to replace an existing L7
mapping.
Signed-off-by: Andrei Dulea <adulea@amazon.de>
---
drivers/iommu/amd_iommu.c | 40 ++++++++++++++++++++++++++++-----------
1 file changed, 29 insertions(+), 11 deletions(-)
diff --git a/drivers/iommu/amd_iommu.c b/drivers/iommu/amd_iommu.c
index c7e28a8d25d1..a227e7a9b8b7 100644
--- a/drivers/iommu/amd_iommu.c
+++ b/drivers/iommu/amd_iommu.c
@@ -501,6 +501,29 @@ static void iommu_uninit_device(struct device *dev)
*/
}
+/*
+ * Helper function to get the first pte of a large mapping
+ */
+static u64 *first_pte_l7(u64 *pte, unsigned long *page_size,
+ unsigned long *count)
+{
+ unsigned long pte_mask, pg_size, cnt;
+ u64 *fpte;
+
+ pg_size = PTE_PAGE_SIZE(*pte);
+ cnt = PAGE_SIZE_PTE_COUNT(pg_size);
+ pte_mask = ~((cnt << 3) - 1);
+ fpte = (u64 *)(((unsigned long)pte) & pte_mask);
+
+ if (page_size)
+ *page_size = pg_size;
+
+ if (count)
+ *count = cnt;
+
+ return fpte;
+}
+
/****************************************************************************
*
* Interrupt handling functions
@@ -1567,17 +1590,12 @@ static u64 *fetch_pte(struct protection_domain *domain,
*page_size = PTE_LEVEL_PAGE_SIZE(level);
}
- if (PM_PTE_LEVEL(*pte) == 0x07) {
- unsigned long pte_mask;
-
- /*
- * If we have a series of large PTEs, make
- * sure to return a pointer to the first one.
- */
- *page_size = pte_mask = PTE_PAGE_SIZE(*pte);
- pte_mask = ~((PAGE_SIZE_PTE_COUNT(pte_mask) << 3) - 1);
- pte = (u64 *)(((unsigned long)pte) & pte_mask);
- }
+ /*
+ * If we have a series of large PTEs, make
+ * sure to return a pointer to the first one.
+ */
+ if (PM_PTE_LEVEL(*pte) == PAGE_MODE_7_LEVEL)
+ pte = first_pte_l7(pte, page_size, NULL);
return pte;
}
--
2.17.1
_______________________________________________
iommu mailing list
iommu@lists.linux-foundation.org
https://lists.linuxfoundation.org/mailman/listinfo/iommu
next prev parent reply other threads:[~2019-09-13 15:11 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-09-13 14:42 [PATCH 0/4] iommu/amd: re-mapping fixes Andrei Dulea via iommu
2019-09-13 14:42 ` [PATCH 1/4] iommu/amd: Fix pages leak in free_pagetable() Andrei Dulea via iommu
2019-09-24 9:21 ` Joerg Roedel
2019-09-13 14:42 ` [PATCH 2/4] iommu/amd: Fix downgrading default page-sizes in alloc_pte() Andrei Dulea via iommu
2019-09-13 14:42 ` Andrei Dulea via iommu [this message]
2019-09-13 14:42 ` [PATCH 4/4] iommu/amd: Unmap all L7 PTEs when downgrading page-sizes Andrei Dulea via iommu
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=20190913144231.21382-4-adulea@amazon.de \
--to=iommu@lists.linux-foundation.org \
--cc=adulea@amazon.de \
--cc=joro@8bytes.org \
--cc=jschoenh@amazon.de \
/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).