[PATCH part2 6/6] PCI: Claim hw/fw allocated resources in hot add path.

[Yinghai Lu <yinghai@kernel.org>]

During testing remove/rescan root bus 00, found
[  338.142574] bus: 'pci': really_probe: probing driver ata_piix with device 0000:00:01.1
[  338.146788] ata_piix 0000:00:01.1: device not available (can't reserve [io  0x01f0-0x01f7])
[  338.150565] ata_piix: probe of 0000:00:01.1 failed with error -22

because that fixed resource is not claimed from
        arch/x86/pci/i386.c::pcibios_allocate_resources()
that is init path.

Try to claim those resources, so on the remove/rescan will still use old
resources.

It is some kind honoring HW/FW setting in the registers during hot add.
esp root-bus hot add is through acpi, BIOS have chance to set some register
for us.

-v2: add rom resource claiming.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
---
 arch/x86/pci/i386.c |   28 +++++++++++++++++++++-------
 drivers/pci/bus.c   |    2 ++
 include/linux/pci.h |    1 +
 3 files changed, 24 insertions(+), 7 deletions(-)

diff --git a/arch/x86/pci/i386.c b/arch/x86/pci/i386.c
index abf2a61..3cb7d66 100644
--- a/arch/x86/pci/i386.c
+++ b/arch/x86/pci/i386.c
@@ -201,13 +201,15 @@ EXPORT_SYMBOL(pcibios_align_resource);
  *	    as well.
  */
 
-static void __init pcibios_allocate_bridge_resources(struct pci_dev *dev)
+static void pcibios_allocate_bridge_resources(struct pci_dev *dev)
 {
 	int idx;
 	struct resource *r;
 
 	for (idx = PCI_BRIDGE_RESOURCES; idx < PCI_NUM_RESOURCES; idx++) {
 		r = &dev->resource[idx];
+		if (r->parent)	/* Already allocated */
+			continue;
 		if (!r->flags)
 			continue;
 		if (!r->start || pci_claim_resource(dev, idx) < 0) {
@@ -223,7 +225,7 @@ static void __init pcibios_allocate_bridge_resources(struct pci_dev *dev)
 	}
 }
 
-static void __init pcibios_allocate_bus_resources(struct pci_bus *bus)
+static void pcibios_allocate_bus_resources(struct pci_bus *bus)
 {
 	struct pci_bus *child;
 
@@ -239,7 +241,7 @@ struct pci_check_idx_range {
 	int end;
 };
 
-static void __init pcibios_allocate_dev_resources(struct pci_dev *dev, int pass)
+static void pcibios_allocate_dev_resources(struct pci_dev *dev, int pass)
 {
 	int idx, disabled, i;
 	u16 command;
@@ -292,7 +294,7 @@ static void __init pcibios_allocate_dev_resources(struct pci_dev *dev, int pass)
 	}
 }
 
-static void __init pcibios_allocate_resources(struct pci_bus *bus, int pass)
+static void pcibios_allocate_resources(struct pci_bus *bus, int pass)
 {
 	struct pci_dev *dev;
 	struct pci_bus *child;
@@ -306,7 +308,7 @@ static void __init pcibios_allocate_resources(struct pci_bus *bus, int pass)
 	}
 }
 
-static void __init pcibios_allocate_dev_rom_resource(struct pci_dev *dev)
+static void pcibios_allocate_dev_rom_resource(struct pci_dev *dev)
 {
 	struct resource *r;
 
@@ -324,7 +326,7 @@ static void __init pcibios_allocate_dev_rom_resource(struct pci_dev *dev)
 		r->start = 0;
 	}
 }
-static void __init __pcibios_allocate_rom_resources(struct pci_bus *bus)
+static void __pcibios_allocate_rom_resources(struct pci_bus *bus)
 {
 	struct pci_dev *dev;
 	struct pci_bus *child;
@@ -337,7 +339,7 @@ static void __init __pcibios_allocate_rom_resources(struct pci_bus *bus)
 			__pcibios_allocate_rom_resources(child);
 	}
 }
-static void __init pcibios_allocate_rom_resources(struct pci_bus *bus)
+static void pcibios_allocate_rom_resources(struct pci_bus *bus)
 {
 	if (pci_probe & PCI_ASSIGN_ROMS)
 		return;
@@ -358,6 +360,18 @@ static int __init pcibios_assign_resources(void)
 	return 0;
 }
 
+void pcibios_resource_survey_bus(struct pci_bus *bus)
+{
+	dev_printk(KERN_DEBUG, &bus->dev, "Allocating resources\n");
+
+	pcibios_allocate_bus_resources(bus);
+
+	pcibios_allocate_resources(bus, 0);
+	pcibios_allocate_resources(bus, 1);
+
+	pcibios_allocate_rom_resources(bus);
+}
+
 void __init pcibios_resource_survey(void)
 {
 	struct pci_bus *bus;
diff --git a/drivers/pci/bus.c b/drivers/pci/bus.c
index 4b0970b..2882d01 100644
--- a/drivers/pci/bus.c
+++ b/drivers/pci/bus.c
@@ -154,6 +154,8 @@ pci_bus_alloc_resource(struct pci_bus *bus, struct resource *res,
 	return ret;
 }
 
+void __weak pcibios_resource_survey_bus(struct pci_bus *bus) { }
+
 /**
  * pci_bus_add_device - add a single device
  * @dev: device to add
diff --git a/include/linux/pci.h b/include/linux/pci.h
index 1b460e1..29a4704 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -676,6 +676,7 @@ extern struct list_head pci_root_buses;	/* list of all known PCI buses */
 /* Some device drivers need know if pci is initiated */
 extern int no_pci_devices(void);
 
+void pcibios_resource_survey_bus(struct pci_bus *bus);
 void pcibios_fixup_bus(struct pci_bus *);
 int __must_check pcibios_enable_device(struct pci_dev *, int mask);
 /* Architecture specific versions may override this (weak) */
-- 
1.7.7