From d5fe8207d8786142061fb18c8fb671b34649f114 Mon Sep 17 00:00:00 2001 From: Philipp Stanner Date: Thu, 13 Jun 2024 13:50:15 +0200 Subject: [PATCH] PCI: Add devres helpers for iomap table MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit The pcim_iomap_devres.table administrated by pcim_iomap_table() has its entries set and unset at several places throughout devres.c using manual iterations which are effectively code duplications. Add pcim_add_mapping_to_legacy_table() and pcim_remove_mapping_from_legacy_table() helper functions and use them where possible. Link: https://lore.kernel.org/r/20240613115032.29098-3-pstanner@redhat.com Signed-off-by: Philipp Stanner Signed-off-by: Krzysztof Wilczyński Signed-off-by: Bjorn Helgaas --- drivers/pci/devres.c | 77 +++++++++++++++++++++++++++++++++----------- 1 file changed, 58 insertions(+), 19 deletions(-) diff --git a/drivers/pci/devres.c b/drivers/pci/devres.c index f13edd4a3873..845d6fab0ce7 100644 --- a/drivers/pci/devres.c +++ b/drivers/pci/devres.c @@ -297,6 +297,52 @@ void __iomem * const *pcim_iomap_table(struct pci_dev *pdev) } EXPORT_SYMBOL(pcim_iomap_table); +/* + * Fill the legacy mapping-table, so that drivers using the old API can + * still get a BAR's mapping address through pcim_iomap_table(). + */ +static int pcim_add_mapping_to_legacy_table(struct pci_dev *pdev, + void __iomem *mapping, int bar) +{ + void __iomem **legacy_iomap_table; + + if (bar >= PCI_STD_NUM_BARS) + return -EINVAL; + + legacy_iomap_table = (void __iomem **)pcim_iomap_table(pdev); + if (!legacy_iomap_table) + return -ENOMEM; + + /* The legacy mechanism doesn't allow for duplicate mappings. */ + WARN_ON(legacy_iomap_table[bar]); + + legacy_iomap_table[bar] = mapping; + + return 0; +} + +/* + * Remove a mapping. The table only contains whole-BAR mappings, so this will + * never interfere with ranged mappings. + */ +static void pcim_remove_mapping_from_legacy_table(struct pci_dev *pdev, + void __iomem *addr) +{ + int bar; + void __iomem **legacy_iomap_table; + + legacy_iomap_table = (void __iomem **)pcim_iomap_table(pdev); + if (!legacy_iomap_table) + return; + + for (bar = 0; bar < PCI_STD_NUM_BARS; bar++) { + if (legacy_iomap_table[bar] == addr) { + legacy_iomap_table[bar] = NULL; + return; + } + } +} + /** * pcim_iomap - Managed pcim_iomap() * @pdev: PCI device to iomap for @@ -308,16 +354,20 @@ EXPORT_SYMBOL(pcim_iomap_table); */ void __iomem *pcim_iomap(struct pci_dev *pdev, int bar, unsigned long maxlen) { - void __iomem **tbl; + void __iomem *mapping; - BUG_ON(bar >= PCIM_IOMAP_MAX); - - tbl = (void __iomem **)pcim_iomap_table(pdev); - if (!tbl || tbl[bar]) /* duplicate mappings not allowed */ + mapping = pci_iomap(pdev, bar, maxlen); + if (!mapping) return NULL; - tbl[bar] = pci_iomap(pdev, bar, maxlen); - return tbl[bar]; + if (pcim_add_mapping_to_legacy_table(pdev, mapping, bar) != 0) + goto err_table; + + return mapping; + +err_table: + pci_iounmap(pdev, mapping); + return NULL; } EXPORT_SYMBOL(pcim_iomap); @@ -330,20 +380,9 @@ EXPORT_SYMBOL(pcim_iomap); */ void pcim_iounmap(struct pci_dev *pdev, void __iomem *addr) { - void __iomem **tbl; - int i; - pci_iounmap(pdev, addr); - tbl = (void __iomem **)pcim_iomap_table(pdev); - BUG_ON(!tbl); - - for (i = 0; i < PCIM_IOMAP_MAX; i++) - if (tbl[i] == addr) { - tbl[i] = NULL; - return; - } - WARN_ON(1); + pcim_remove_mapping_from_legacy_table(pdev, addr); } EXPORT_SYMBOL(pcim_iounmap); -- 2.25.1