PCI: Use pci_release_resource() instead of release_resource()

A few places in setup-bus.c call release_resource() directly and end up
duplicating functionality from pci_release_resource() such as parent check,
logging, and clearing the resource. Worse yet, the way the resource is
cleared is inconsistent between different sites.

Convert release_resource() calls into pci_release_resource() to remove code
duplication. This will also make the resource start, end, and flags
behavior consistent, i.e., start address is cleared, and only
IORESOURCE_UNSET is asserted for the resource.

While at it, eliminate the unnecessary initialization of idx variable in
pci_bridge_release_resources().

Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Link: https://patch.msgid.link/20250829131113.36754-9-ilpo.jarvinen@linux.intel.com

diff --git a/drivers/pci/setup-bus.c b/drivers/pci/setup-bus.c
index 6bdc1af887dad58b109a7dd2eaa9e17244419da5..b62465665abc9af6d4c2b913cd6939696415ad1c 100644 (file)
--- a/drivers/pci/setup-bus.c
+++ b/drivers/pci/setup-bus.c
@@ -473,8 +473,6 @@ static void __assign_resources_sorted(struct list_head *head,
        struct pci_dev_resource *dev_res, *tmp_res, *dev_res2;
        struct resource *res;
        struct pci_dev *dev;
-       const char *res_name;
-       int idx;
        unsigned long fail_type;
        resource_size_t add_align, align;
 
@@ -582,14 +580,7 @@ assign:
                res = dev_res->res;
                dev = dev_res->dev;
 
-               if (!res->parent)
-                       continue;
-
-               idx = pci_resource_num(dev, res);
-               res_name = pci_resource_name(dev, idx);
-               pci_dbg(dev, "%s %pR: releasing\n", res_name, res);
-
-               release_resource(res);
+               pci_release_resource(dev, pci_resource_num(dev, res));
                restore_dev_resource(dev_res);
        }
        /* Restore start/end/flags from saved list */
@@ -1732,7 +1723,7 @@ static void pci_bridge_release_resources(struct pci_bus *bus,
        struct resource *r;
        unsigned int old_flags;
        struct resource *b_res;
-       int idx = 1;
+       int idx, ret;
 
        b_res = &dev->resource[PCI_BRIDGE_RESOURCES];
 
@@ -1766,21 +1757,18 @@ static void pci_bridge_release_resources(struct pci_bus *bus,
 
        /* If there are children, release them all */
        release_child_resources(r);
-       if (!release_resource(r)) {
-               type = old_flags = r->flags & PCI_RES_TYPE_MASK;
-               pci_info(dev, "resource %d %pR released\n",
-                        PCI_BRIDGE_RESOURCES + idx, r);
-               /* Keep the old size */
-               resource_set_range(r, 0, resource_size(r));
-               r->flags = 0;
 
-               /* Avoiding touch the one without PREF */
-               if (type & IORESOURCE_PREFETCH)
-                       type = IORESOURCE_PREFETCH;
-               __pci_setup_bridge(bus, type);
-               /* For next child res under same bridge */
-               r->flags = old_flags;
-       }
+       type = old_flags = r->flags & PCI_RES_TYPE_MASK;
+       ret = pci_release_resource(dev, PCI_BRIDGE_RESOURCES + idx);
+       if (ret)
+               return;
+
+       /* Avoiding touch the one without PREF */
+       if (type & IORESOURCE_PREFETCH)
+               type = IORESOURCE_PREFETCH;
+       __pci_setup_bridge(bus, type);
+       /* For next child res under same bridge */
+       r->flags = old_flags;
 }
 
 enum release_type {
@@ -2425,7 +2413,6 @@ int pci_reassign_bridge_resources(struct pci_dev *bridge, unsigned long type)
                for (i = PCI_BRIDGE_RESOURCES; i < PCI_BRIDGE_RESOURCE_END;
                     i++) {
                        struct resource *res = &bridge->resource[i];
-                       const char *res_name = pci_resource_name(bridge, i);
 
                        if ((res->flags ^ type) & PCI_RES_TYPE_MASK)
                                continue;
@@ -2438,12 +2425,7 @@ int pci_reassign_bridge_resources(struct pci_dev *bridge, unsigned long type)
                        if (ret)
                                goto cleanup;
 
-                       pci_info(bridge, "%s %pR: releasing\n", res_name, res);
-
-                       if (res->parent)
-                               release_resource(res);
-                       res->start = 0;
-                       res->end = 0;
+                       pci_release_resource(bridge, i);
                        break;
                }
                if (i == PCI_BRIDGE_RESOURCE_END)

diff --git a/drivers/pci/setup-res.c b/drivers/pci/setup-res.c
index d2b3ed51e88048962557bc04038e8b19f40478a6..0468c058b598723b6946af4962f46dad5f9108d9 100644 (file)
--- a/drivers/pci/setup-res.c
+++ b/drivers/pci/setup-res.c
@@ -406,20 +406,25 @@ int pci_reassign_resource(struct pci_dev *dev, int resno,
        return 0;
 }
 
-void pci_release_resource(struct pci_dev *dev, int resno)
+int pci_release_resource(struct pci_dev *dev, int resno)
 {
        struct resource *res = pci_resource_n(dev, resno);
        const char *res_name = pci_resource_name(dev, resno);
+       int ret;
 
        if (!res->parent)
-               return;
+               return 0;
 
        pci_info(dev, "%s %pR: releasing\n", res_name, res);
 
-       release_resource(res);
+       ret = release_resource(res);
+       if (ret)
+               return ret;
        res->end = resource_size(res) - 1;
        res->start = 0;
        res->flags |= IORESOURCE_UNSET;
+
+       return 0;
 }
 EXPORT_SYMBOL(pci_release_resource);
 

diff --git a/include/linux/pci.h b/include/linux/pci.h
index 59876de13860dbe50ee6c207cd57e54f51a11079..275df40587672ac99dff566710d10c48ba617c79 100644 (file)
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -1417,7 +1417,7 @@ void pci_reset_secondary_bus(struct pci_dev *dev);
 void pcibios_reset_secondary_bus(struct pci_dev *dev);
 void pci_update_resource(struct pci_dev *dev, int resno);
 int __must_check pci_assign_resource(struct pci_dev *dev, int i);
-void pci_release_resource(struct pci_dev *dev, int resno);
+int pci_release_resource(struct pci_dev *dev, int resno);
 static inline int pci_rebar_bytes_to_size(u64 bytes)
 {
        bytes = roundup_pow_of_two(bytes);