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Map such a range for being used as the ctpio buffer. > > > > > > A potential user space action through sysfs unbinding or core cxl > > > modules remove will trigger sfc driver device detachment, with that case > > > not racing with this mapping as this is done during driver probe and > > > therefore protected with device lock against those user space actions. > > > > > > Signed-off-by: Alejandro Lucero > > > Reviewed-by: Dave Jiang > > > Acked-by: Edward Cree > > > --- > > > drivers/net/ethernet/sfc/efx.c | 2 ++ > > > drivers/net/ethernet/sfc/efx_cxl.c | 23 +++++++++++++++++++++++ > > > drivers/net/ethernet/sfc/efx_cxl.h | 3 +++ > > > 3 files changed, 28 insertions(+) > > > > > > diff --git a/drivers/net/ethernet/sfc/efx.c b/drivers/net/ethernet/sfc/efx.c > > > index 61cbb6cfc360..3806cd3dd7f4 100644 > > > --- a/drivers/net/ethernet/sfc/efx.c > > > +++ b/drivers/net/ethernet/sfc/efx.c > > > @@ -984,6 +984,7 @@ static void efx_pci_remove(struct pci_dev *pci_dev) > > > efx_fini_io(efx); > > > probe_data = container_of(efx, struct efx_probe_data, efx); > > > + efx_cxl_exit(probe_data); > > > pci_dbg(efx->pci_dev, "shutdown successful\n"); > > > @@ -1242,6 +1243,7 @@ static int efx_pci_probe(struct pci_dev *pci_dev, > > > return 0; > > > fail3: > > > + efx_cxl_exit(probe_data); > > > efx_fini_io(efx); > > > fail2: > > > efx_fini_struct(efx); > > > diff --git a/drivers/net/ethernet/sfc/efx_cxl.c b/drivers/net/ethernet/sfc/efx_cxl.c > > > index 18b535b3ea40..3e7c950f83e9 100644 > > > --- a/drivers/net/ethernet/sfc/efx_cxl.c > > > +++ b/drivers/net/ethernet/sfc/efx_cxl.c > > > @@ -18,6 +18,7 @@ int efx_cxl_init(struct efx_probe_data *probe_data) > > > { > > > struct efx_nic *efx = &probe_data->efx; > > > struct pci_dev *pci_dev = efx->pci_dev; > > > + struct range cxl_pio_range; > > > struct efx_cxl *cxl; > > > u16 dvsec; > > > int rc; > > > @@ -73,9 +74,31 @@ int efx_cxl_init(struct efx_probe_data *probe_data) > > > return -ENODEV; > > > } > > > + cxl->cxlmd = devm_cxl_probe_mem(&cxl->cxlds, &cxl_pio_range); > > > + if (IS_ERR(cxl->cxlmd)) { > > > + pci_err(pci_dev, "CXL accel memdev creation failed\n"); > > > + return PTR_ERR(cxl->cxlmd); > > > + } > > > + > > > + cxl->ctpio_cxl = ioremap_wc(cxl_pio_range.start, > > > + range_len(&cxl_pio_range)); > > Hi Alejandro, > > > > A small question here, > > Is it possible that the FW would commit a region bigger than the range ? > > > Hi Richard, > > > Not really. We are using the minimum size for CXL mem, 256MB, and it is not > configurable. If CXL is enabled by the sfc device firmware, this is the only > possibility. > > It could be a good sanity check though, but I prefer to keep v29 as it is > now ... Dan Williams is happy enough with it, so I expect Dave to merge it > soon ... > > > Maybe as a follow up path. > > > Thank you, > > Alejandro > > Hi Alejandro, I see, thanks for the head up . Np for me then, thanks. --Richard > > The committed CXL region length is never validated against the PIO window size. > > The legacy patch sizes wc_mem_map_size to cover the VI-strided PIO offset, but > > here we ioremap whatever the BIOS comitted and assume it's EFX_CTPIO_BUFFER_SIZE. > > > > Maybe adding > > """ > > if (range_len(&cxl_pio_range) < EFX_CTPIO_BUFFER_SIZE) > > return -EINVAL; > > """ > > Would be worthy ? > > > > Let me know what you think. > > > > Best regards, > > Richard Cheng > > > > > + if (!cxl->ctpio_cxl) { > > > + pci_err(pci_dev, "CXL ioremap region (%pra) failed\n", > > > + &cxl_pio_range); > > > + return -ENOMEM; > > > + } > > > + > > > probe_data->cxl = cxl; > > > return 0; > > > } > > > +void efx_cxl_exit(struct efx_probe_data *probe_data) > > > +{ > > > + if (!probe_data->cxl) > > > + return; > > > + > > > + iounmap(probe_data->cxl->ctpio_cxl); > > > +} > > > + > > > MODULE_IMPORT_NS("CXL"); > > > diff --git a/drivers/net/ethernet/sfc/efx_cxl.h b/drivers/net/ethernet/sfc/efx_cxl.h > > > index 04e46278464d..3e2705cb063f 100644 > > > --- a/drivers/net/ethernet/sfc/efx_cxl.h > > > +++ b/drivers/net/ethernet/sfc/efx_cxl.h > > > @@ -20,10 +20,13 @@ struct efx_probe_data; > > > struct efx_cxl { > > > struct cxl_dev_state cxlds; > > > struct cxl_memdev *cxlmd; > > > + void __iomem *ctpio_cxl; > > > }; > > > int efx_cxl_init(struct efx_probe_data *probe_data); > > > +void efx_cxl_exit(struct efx_probe_data *probe_data); > > > #else > > > static inline int efx_cxl_init(struct efx_probe_data *probe_data) { return 0; } > > > +static inline void efx_cxl_exit(struct efx_probe_data *probe_data) {} > > > #endif > > > #endif > > > -- > > > 2.34.1 > > > > > >