[PATCH 2/2] PCI: endpoint: pci-epf-vntb: simplify ctrl/spad space allocation

From: Jerome Brunet
Date: Fri Mar 28 2025 - 10:54:27 EST


When allocating the shared ctrl/spad space, epf_ntb_config_spad_bar_alloc()
should not try to handle the size quirks for the underlying BAR, whether it
is fixed size or alignment. This is already handled by
pci_epf_alloc_space().

Also, when handling the alignment, this allocate more space than necessary.
For example, with a spad size of 1024B and a ctrl size of 308B, the space
necessary is 1332B. If the alignment is 1MB,
epf_ntb_config_spad_bar_alloc() tries to allocate 2MB where 1MB would have
been more than enough.

Just drop all the handling of the BAR size quirks and let
pci_epf_alloc_space() handle that.

Signed-off-by: Jerome Brunet <jbrunet@xxxxxxxxxxxx>
---
drivers/pci/endpoint/functions/pci-epf-vntb.c | 24 ++----------------------
1 file changed, 2 insertions(+), 22 deletions(-)

diff --git a/drivers/pci/endpoint/functions/pci-epf-vntb.c b/drivers/pci/endpoint/functions/pci-epf-vntb.c
index 874cb097b093ae645bbc4bf3c9d28ca812d7689d..c20a60fcb99e6e16716dd78ab59ebf7cf074b2a6 100644
--- a/drivers/pci/endpoint/functions/pci-epf-vntb.c
+++ b/drivers/pci/endpoint/functions/pci-epf-vntb.c
@@ -408,11 +408,9 @@ static void epf_ntb_config_spad_bar_free(struct epf_ntb *ntb)
*/
static int epf_ntb_config_spad_bar_alloc(struct epf_ntb *ntb)
{
- size_t align;
enum pci_barno barno;
struct epf_ntb_ctrl *ctrl;
u32 spad_size, ctrl_size;
- u64 size;
struct pci_epf *epf = ntb->epf;
struct device *dev = &epf->dev;
u32 spad_count;
@@ -422,31 +420,13 @@ static int epf_ntb_config_spad_bar_alloc(struct epf_ntb *ntb)
epf->func_no,
epf->vfunc_no);
barno = ntb->epf_ntb_bar[BAR_CONFIG];
- size = epc_features->bar[barno].fixed_size;
- align = epc_features->align;
-
- if ((!IS_ALIGNED(size, align)))
- return -EINVAL;
-
spad_count = ntb->spad_count;

ctrl_size = sizeof(struct epf_ntb_ctrl);
spad_size = 2 * spad_count * sizeof(u32);

- if (!align) {
- ctrl_size = roundup_pow_of_two(ctrl_size);
- spad_size = roundup_pow_of_two(spad_size);
- } else {
- ctrl_size = ALIGN(ctrl_size, align);
- spad_size = ALIGN(spad_size, align);
- }
-
- if (!size)
- size = ctrl_size + spad_size;
- else if (size < ctrl_size + spad_size)
- return -EINVAL;
-
- base = pci_epf_alloc_space(epf, size, barno, epc_features, 0);
+ base = pci_epf_alloc_space(epf, ctrl_size + spad_size,
+ barno, epc_features, 0);
if (!base) {
dev_err(dev, "Config/Status/SPAD alloc region fail\n");
return -ENOMEM;

--
2.47.2