From bb1fabd0d94efc29f88f86fb996c40ac06db3669 Mon Sep 17 00:00:00 2001 From: Ilpo Järvinen Date: Thu, 13 Nov 2025 20:00:47 +0200 Subject: PCI: Add pci_rebar_size_supported() helper MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Many callers of pci_rebar_get_possible_sizes() are interested in finding out if a particular encoded BAR Size (PCIe r7.0, sec 7.8.6.3) is supported by the particular BAR. Add pci_rebar_size_supported() into PCI core to make it easy for the drivers to determine if the BAR size is supported or not. Use the new function in pci_resize_resource() and in pci_iov_vf_bar_set_size(). Signed-off-by: Ilpo Järvinen Signed-off-by: Bjorn Helgaas Reviewed-by: Christian König Reviewed-by: Andi Shyti Link: https://patch.msgid.link/20251113180053.27944-6-ilpo.jarvinen@linux.intel.com --- drivers/pci/rebar.c | 25 +++++++++++++++++++------ 1 file changed, 19 insertions(+), 6 deletions(-) (limited to 'drivers/pci/rebar.c') diff --git a/drivers/pci/rebar.c b/drivers/pci/rebar.c index 399660cb12fa..1c90b606b8d4 100644 --- a/drivers/pci/rebar.c +++ b/drivers/pci/rebar.c @@ -3,6 +3,7 @@ * PCI Resizable BAR Extended Capability handling. */ +#include #include #include #include @@ -124,6 +125,23 @@ u32 pci_rebar_get_possible_sizes(struct pci_dev *pdev, int bar) } EXPORT_SYMBOL(pci_rebar_get_possible_sizes); +/** + * pci_rebar_size_supported - check if size is supported for BAR + * @pdev: PCI device + * @bar: BAR to check + * @size: encoded size as defined in the PCIe spec (0=1MB, 31=128TB) + * + * Return: %true if @bar is resizable and @size is supported, otherwise + * %false. + */ +bool pci_rebar_size_supported(struct pci_dev *pdev, int bar, int size) +{ + u64 sizes = pci_rebar_get_possible_sizes(pdev, bar); + + return BIT(size) & sizes; +} +EXPORT_SYMBOL_GPL(pci_rebar_size_supported); + /** * pci_rebar_get_current_size - get the current size of a Resizable BAR * @pdev: PCI device @@ -252,7 +270,6 @@ int pci_resize_resource(struct pci_dev *dev, int resno, int size, { struct pci_host_bridge *host; int old, ret; - u32 sizes; /* Check if we must preserve the firmware's resource assignment */ host = pci_find_host_bridge(dev->bus); @@ -262,11 +279,7 @@ int pci_resize_resource(struct pci_dev *dev, int resno, int size, if (pci_resize_is_memory_decoding_enabled(dev, resno)) return -EBUSY; - sizes = pci_rebar_get_possible_sizes(dev, resno); - if (!sizes) - return -ENOTSUPP; - - if (!(sizes & BIT(size))) + if (!pci_rebar_size_supported(dev, resno, size)) return -EINVAL; old = pci_rebar_get_current_size(dev, resno); -- cgit