diff mbox series

[v4] pci_vfio: Support 64KB kernel page_size with vfio-pci driver

Message ID 1544613959-14349-1-git-send-email-tone.zhang@arm.com (mailing list archive)
State Accepted, archived
Delegated to: Thomas Monjalon
Headers
Series [v4] pci_vfio: Support 64KB kernel page_size with vfio-pci driver |

Checks

Context Check Description
ci/checkpatch success coding style OK
ci/Intel-compilation success Compilation OK
ci/mellanox-Performance-Testing success Performance Testing PASS
ci/intel-Performance-Testing success Performance Testing PASS

Commit Message

tone.zhang Dec. 12, 2018, 11:25 a.m. UTC 
  With a larger PAGE_SIZE it is possible for the MSI table to very
close to the end of the BAR s.t. when we align the start and end
of the MSI table to the PAGE_SIZE, the end offset of the MSI
table is out of the PCI BAR boundary.

This patch addresses the issue by comparing both the start and the
end offset of the MSI table with the BAR size, and skip the mapping
if it is out of Bar scope.

The patch fixes the debug log as below:
EAL: Skipping BAR0

Signed-off-by: tone.zhang <tone.zhang@arm.com>
Reviewed-by: Gavin Hu <Gavin.Hu@arm.com>
Reviewed-by: Honnappa Nagarahalli <honnappa.nagarahalli@arm.com>
Reviewed-by: Steve Capper <Steve.Capper@arm.com>
Reviewed-by: Anatoly Burakov <anatoly.burakov@intel.com>
---
 drivers/bus/pci/linux/pci_vfio.c | 29 +++++++++++++++++++++++------
 1 file changed, 23 insertions(+), 6 deletions(-)

Comments

Burakov, Anatoly Dec. 12, 2018, 11:27 a.m. UTC | #1 
On 12-Dec-18 11:25 AM, tone.zhang wrote:
> With a larger PAGE_SIZE it is possible for the MSI table to very
> close to the end of the BAR s.t. when we align the start and end
> of the MSI table to the PAGE_SIZE, the end offset of the MSI
> table is out of the PCI BAR boundary.
> 
> This patch addresses the issue by comparing both the start and the
> end offset of the MSI table with the BAR size, and skip the mapping
> if it is out of Bar scope.
> 
> The patch fixes the debug log as below:
> EAL: Skipping BAR0
> 
> Signed-off-by: tone.zhang <tone.zhang@arm.com>
> Reviewed-by: Gavin Hu <Gavin.Hu@arm.com>
> Reviewed-by: Honnappa Nagarahalli <honnappa.nagarahalli@arm.com>
> Reviewed-by: Steve Capper <Steve.Capper@arm.com>
> Reviewed-by: Anatoly Burakov <anatoly.burakov@intel.com>
> ---

Acked-by: Anatoly Burakov <anatoly.burakov@intel.com>
Thomas Monjalon Dec. 19, 2018, 11:05 p.m. UTC | #2 
12/12/2018 12:27, Burakov, Anatoly:
> On 12-Dec-18 11:25 AM, tone.zhang wrote:
> > With a larger PAGE_SIZE it is possible for the MSI table to very
> > close to the end of the BAR s.t. when we align the start and end
> > of the MSI table to the PAGE_SIZE, the end offset of the MSI
> > table is out of the PCI BAR boundary.
> > 
> > This patch addresses the issue by comparing both the start and the
> > end offset of the MSI table with the BAR size, and skip the mapping
> > if it is out of Bar scope.
> > 
> > The patch fixes the debug log as below:
> > EAL: Skipping BAR0
> > 
> > Signed-off-by: tone.zhang <tone.zhang@arm.com>
> > Reviewed-by: Gavin Hu <Gavin.Hu@arm.com>
> > Reviewed-by: Honnappa Nagarahalli <honnappa.nagarahalli@arm.com>
> > Reviewed-by: Steve Capper <Steve.Capper@arm.com>
> > Reviewed-by: Anatoly Burakov <anatoly.burakov@intel.com>
> > ---
> 
> Acked-by: Anatoly Burakov <anatoly.burakov@intel.com>

Applied, thanks
diff mbox series

Patch

diff --git a/drivers/bus/pci/linux/pci_vfio.c b/drivers/bus/pci/linux/pci_vfio.c
index ffd26f1..22e9de0 100644
--- a/drivers/bus/pci/linux/pci_vfio.c
+++ b/drivers/bus/pci/linux/pci_vfio.c
@@ -457,9 +457,10 @@  pci_vfio_mmap_bar(int vfio_dev_fd, struct mapped_pci_resource *vfio_res,
 	struct pci_msix_table *msix_table = &vfio_res->msix_table;
 	struct pci_map *bar = &vfio_res->maps[bar_index];
 
-	if (bar->size == 0)
-		/* Skip this BAR */
+	if (bar->size == 0) {
+		RTE_LOG(DEBUG, EAL, "Bar size is 0, skip BAR%d\n", bar_index);
 		return 0;
+	}
 
 	if (msix_table->bar_index == bar_index) {
 		/*
@@ -468,8 +469,15 @@  pci_vfio_mmap_bar(int vfio_dev_fd, struct mapped_pci_resource *vfio_res,
 		 */
 		uint32_t table_start = msix_table->offset;
 		uint32_t table_end = table_start + msix_table->size;
-		table_end = (table_end + ~PAGE_MASK) & PAGE_MASK;
-		table_start &= PAGE_MASK;
+		table_end = RTE_ALIGN(table_end, PAGE_SIZE);
+		table_start = RTE_ALIGN_FLOOR(table_start, PAGE_SIZE);
+
+		/* If page-aligned start of MSI-X table is less than the
+		 * actual MSI-X table start address, reassign to the actual
+		 * start address.
+		 */
+		if (table_start < msix_table->offset)
+			table_start = msix_table->offset;
 
 		if (table_start == 0 && table_end >= bar->size) {
 			/* Cannot map this BAR */
@@ -481,8 +489,17 @@  pci_vfio_mmap_bar(int vfio_dev_fd, struct mapped_pci_resource *vfio_res,
 
 		memreg[0].offset = bar->offset;
 		memreg[0].size = table_start;
-		memreg[1].offset = bar->offset + table_end;
-		memreg[1].size = bar->size - table_end;
+		if (bar->size < table_end) {
+			/*
+			 * If MSI-X table end is beyond BAR end, don't attempt
+			 * to perform second mapping.
+			 */
+			memreg[1].offset = 0;
+			memreg[1].size = 0;
+		} else {
+			memreg[1].offset = bar->offset + table_end;
+			memreg[1].size = bar->size - table_end;
+		}
 
 		RTE_LOG(DEBUG, EAL,
 			"Trying to map BAR%d that contains the MSI-X "