[dpdk-dev] [PATCH v3] pci_vfio: Support 64KB kernel page_size with vfio-pci driver
Burakov, Anatoly
anatoly.burakov at intel.com
Mon Dec 10 12:45:37 CET 2018
On 19-Nov-18 2:37 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 at arm.com>
> Reviewed-by: Gavin Hu <Gavin.Hu at arm.com>
> Reviewed-by: Honnappa Nagarahalli <honnappa.nagarahalli at arm.com>
> Reviewed-by: Steve Capper <Steve.Capper at arm.com>
> Reviewed-by: Anatoly Burakov <anatoly.burakov at intel.com>
> ---
> drivers/bus/pci/linux/pci_vfio.c | 27 ++++++++++++++++++++++-----
> 1 file changed, 22 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/bus/pci/linux/pci_vfio.c b/drivers/bus/pci/linux/pci_vfio.c
> index ffd26f1..0e7bfd7 100644
> --- a/drivers/bus/pci/linux/pci_vfio.c
> +++ b/drivers/bus/pci/linux/pci_vfio.c
> @@ -457,9 +457,11 @@ 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)
> + if (bar->size == 0) {
> /* Skip this BAR */
> + RTE_LOG(INFO, EAL, "Skipping BAR%d\n", bar_index);
> return 0;
I would perhaps make it a DEBUG rather than INFO.
> + }
>
> if (msix_table->bar_index == bar_index) {
> /*
> @@ -468,8 +470,14 @@ 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(table_start, PAGE_SIZE);
I believe table_start &= PAGE_MASK is equivalent to table_start =
RTE_ALIGN_FLOOR(), not RTE_ALIGN() (which is an alias for RTE_ALIGN_CEIL()).
> +
> + /* If page-aligned start of MSI-X table is beyond BAR size,
> + * shrink the mapping size to MSI-X table start address.
> + */
> + if (table_start >= bar->size)
> + 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 "
>
--
Thanks,
Anatoly
More information about the dev
mailing list