summaryrefslogtreecommitdiffstats
path: root/drivers/iommu
diff options
context:
space:
mode:
authorAndrei Dulea <adulea@amazon.de>2019-09-13 16:42:30 +0200
committerJoerg Roedel <jroedel@suse.de>2019-09-24 11:15:46 +0200
commit7f1f1683c1e27c280556766cfd2c219957cebe4f (patch)
tree946b5da79e9b8ae988fca051d87a8cf47cf61e01 /drivers/iommu
parent6ccb72f8374e17d60b58a7bfd5570496332c54e2 (diff)
downloadtalos-op-linux-7f1f1683c1e27c280556766cfd2c219957cebe4f.tar.gz
talos-op-linux-7f1f1683c1e27c280556766cfd2c219957cebe4f.zip
iommu/amd: Introduce first_pte_l7() helper
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. Fixes: 6d568ef9a622 ("iommu/amd: Allow downgrading page-sizes in alloc_pte()") Signed-off-by: Andrei Dulea <adulea@amazon.de>
Diffstat (limited to 'drivers/iommu')
-rw-r--r--drivers/iommu/amd_iommu.c40
1 files 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;
}
OpenPOWER on IntegriCloud