[PATCH -v6 0/22] PCI: allocate pci bus num range for unassigned bridge busn + pci rescan cleanup

[PATCH -v6 0/22] PCI: allocate pci bus num range for unassigned bridge busn + pci rescan cleanup

[Yinghai Lu]

c363f32: PCI: clean up rescan_bus_bridge_resize
6aa2709: PCI: make pci_rescan_bus_bridge_resize use pci_scan_bridge instead
37cde7d: PCI: Add pci_bus_add_single_device()
2491eb4: PCI, sysfs: create rescan_bridge under /sys/.../pci/devices/... for pci bridges
2e8ccf8: PCI, sys: Use device_type and attr_groups with pci dev
523106b: PCI, pciehp: Remove not needed bus number range checking
b93a078: PCI: Double checking setting for bus register and bus struct.
d7f3672: pcmcia: remove workaround for fixing pci parent bus subordinate
7fc60fb: PCI: Seperate child bus scanning to two passes overall
c180042: PCI: kill pci_fixup_parent_subordinate_busnr()
e6832b3: PCI: Allocate bus range instead of use max blindly
f4c45ff: PCI: Strict checking of valid range for bridge
d933847: PCI: Probe safe range that we can use for unassigned bridge.
00ca3b1: PCI: Add pci_bus_extend/shrink_top()
81f70bb: PCI, parisc: Register busn_res for root buses
a1e4606: PCI, powerpc: Register busn_res for root buses
c3fbb20: PCI, sparc: Register busn_res for root buses
56f1bb0: PCI, ia64: Register busn_res for root buses
25502fb: PCI, x86: Register busn_res for root buses
311e8e2: PCI: Add busn_res tracking in core
48bf7b6: PCI: Add busn_res operation functions
1431674: PCI: Add busn_res into struct pci_bus.

Set up iobusn_resource tree, and register bus number range to it.
Later when need to find bus range, will try to allocate from the tree

Need to test on arches other than x86. esp for ia64 and powerpc that support
  more than on peer root buses.

last five patches are rescan cleanup that make use busn alloc.

could be found at:
	git://git.kernel.org/pub/scm/linux/kernel/git/yinghai/linux-yinghai.git for-pci-busn-alloc

-v2: according to Jesse, split to more small patches.
-v3: address some request from Bjorn. like make use %pR for busn_res debug print
	out, and move the comment change with code change.
-v4: fixes the problem about rescan that Bjorn found.
-v5: add /proc/iobusn that is requested by Bjorn.
     remove old workaround from pciehp.
     add rescan_bridge for pci bridge in /sys
-v6: remove global iobusn_resource, and every root bus's busn_res will be root
     of children buses' busn_res.
     pc cardbus change is tested by pcmcia maintainter.

Thanks

Yinghai

 Documentation/ABI/testing/sysfs-bus-pci |   10 +
 arch/ia64/pci/pci.c                     |    2 +
 arch/powerpc/kernel/pci-common.c        |    7 +-
 arch/sparc/kernel/pci.c                 |    1 +
 arch/x86/include/asm/topology.h         |    3 +-
 arch/x86/pci/acpi.c                     |    8 +-
 arch/x86/pci/bus_numa.c                 |    8 +-
 arch/x86/pci/common.c                   |   11 +-
 drivers/parisc/dino.c                   |    2 +
 drivers/parisc/lba_pci.c                |    3 +
 drivers/pci/bus.c                       |   40 +++
 drivers/pci/hotplug/pciehp_pci.c        |   12 +-
 drivers/pci/pci-sysfs.c                 |   59 ++++-
 drivers/pci/pci.h                       |    1 +
 drivers/pci/probe.c                     |  460 +++++++++++++++++++++++++------
 drivers/pci/remove.c                    |    1 +
 drivers/pcmcia/yenta_socket.c           |   75 -----
 include/linux/pci.h                     |    9 +
 18 files changed, 525 insertions(+), 187 deletions(-)

[PATCH 01/22] PCI: Add busn_res into struct pci_bus.

[Yinghai Lu]

will use it to have bus number resource tree.

-v2: remove iobusn_resource

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
---
 include/linux/pci.h |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)

diff --git a/include/linux/pci.h b/include/linux/pci.h
index f8caaab..94ad468 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -419,6 +419,7 @@ struct pci_bus {
 	struct list_head slots;		/* list of slots on this bus */
 	struct resource *resource[PCI_BRIDGE_RESOURCE_NUM];
 	struct list_head resources;	/* address space routed to this bus */
+	struct resource busn_res;	/* track registered bus num range */
 
 	struct pci_ops	*ops;		/* configuration access functions */
 	void		*sysdata;	/* hook for sys-specific extension */
-- 
1.7.7

[PATCH 02/22] PCI: Add busn_res operation functions

[Yinghai Lu]

will use them insert/update busn res in pci_bus

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
---
 drivers/pci/probe.c |   47 +++++++++++++++++++++++++++++++++++++++++++++++
 include/linux/pci.h |    3 +++
 2 files changed, 50 insertions(+), 0 deletions(-)

diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index a114173..480670f 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -1622,6 +1622,53 @@ err_out:
 	return NULL;
 }
 
+void pci_bus_insert_busn_res(struct pci_bus *b, int bus, int bus_max)
+{
+	struct resource *res = &b->busn_res;
+	struct resource *parent_res;
+	int ret;
+
+	res->start = bus;
+	res->end = bus_max;
+	res->flags = IORESOURCE_BUS;
+
+	/* no parent for root bus' busn_res */
+	if (!pci_is_root_bus(b)) {
+		parent_res = &b->parent->busn_res;
+
+		ret = insert_resource(parent_res, res);
+
+		dev_printk(KERN_DEBUG, &b->dev,
+			"busn_res: %pR %s inserted under %pR\n",
+			res, ret ? "can not be" : "is", parent_res);
+	} else
+		dev_printk(KERN_DEBUG, &b->dev,
+			"busn_res: %pR for root bus\n",
+			res);
+}
+
+void pci_bus_update_busn_res_end(struct pci_bus *b, int bus_max)
+{
+	struct resource *res = &b->busn_res;
+	struct resource old_res = *res;
+
+	res->end = bus_max;
+	dev_printk(KERN_DEBUG, &b->dev,
+			"busn_res: %pR end updated to %pR\n",
+			&old_res, res);
+}
+
+void pci_bus_release_busn_res(struct pci_bus *b)
+{
+	struct resource *res = &b->busn_res;
+	int ret;
+
+	ret = release_resource(res);
+	dev_printk(KERN_DEBUG, &b->dev,
+			"busn_res: %pR %s released\n",
+			res, ret ? "can not be" : "is");
+}
+
 struct pci_bus * __devinit pci_scan_root_bus(struct device *parent, int bus,
 		struct pci_ops *ops, void *sysdata, struct list_head *resources)
 {
diff --git a/include/linux/pci.h b/include/linux/pci.h
index 94ad468..3da935c 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -665,6 +665,9 @@ struct pci_bus *pci_scan_bus(int bus, struct pci_ops *ops, void *sysdata);
 struct pci_bus *pci_create_root_bus(struct device *parent, int bus,
 				    struct pci_ops *ops, void *sysdata,
 				    struct list_head *resources);
+void pci_bus_insert_busn_res(struct pci_bus *b, int bus, int busmax);
+void pci_bus_update_busn_res_end(struct pci_bus *b, int busmax);
+void pci_bus_release_busn_res(struct pci_bus *b);
 struct pci_bus * __devinit pci_scan_root_bus(struct device *parent, int bus,
 					     struct pci_ops *ops, void *sysdata,
 					     struct list_head *resources);
-- 
1.7.7

[PATCH 03/22] PCI: Add busn_res tracking in core

[Yinghai Lu]

update pci_scan_root_bus, and pci_scan_bus to insert root bus busn into
iobusn_resource tree.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
---
 drivers/pci/probe.c  |   30 ++++++++++++++++++++++++++----
 drivers/pci/remove.c |    1 +
 include/linux/pci.h  |    4 ++++
 3 files changed, 31 insertions(+), 4 deletions(-)

diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index 480670f..33cc54e 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -1669,8 +1669,9 @@ void pci_bus_release_busn_res(struct pci_bus *b)
 			res, ret ? "can not be" : "is");
 }
 
-struct pci_bus * __devinit pci_scan_root_bus(struct device *parent, int bus,
-		struct pci_ops *ops, void *sysdata, struct list_head *resources)
+struct pci_bus * __devinit pci_scan_root_bus_max(struct device *parent, int bus,
+		int bus_max, struct pci_ops *ops, void *sysdata,
+		struct list_head *resources)
 {
 	struct pci_bus *b;
 
@@ -1678,10 +1679,26 @@ struct pci_bus * __devinit pci_scan_root_bus(struct device *parent, int bus,
 	if (!b)
 		return NULL;
 
+	pci_bus_insert_busn_res(b, bus, bus_max);
 	b->subordinate = pci_scan_child_bus(b);
 	pci_bus_add_devices(b);
 	return b;
 }
+EXPORT_SYMBOL(pci_scan_root_bus_max);
+
+struct pci_bus * __devinit pci_scan_root_bus(struct device *parent, int bus,
+		struct pci_ops *ops, void *sysdata,
+		struct list_head *resources)
+{
+	struct pci_bus *b;
+
+	b = pci_scan_root_bus_max(parent, bus, 255, ops, sysdata, resources);
+
+	if (b)
+		pci_bus_update_busn_res_end(b, b->subordinate);
+
+	return b;
+}
 EXPORT_SYMBOL(pci_scan_root_bus);
 
 /* Deprecated; use pci_scan_root_bus() instead */
@@ -1694,9 +1711,11 @@ struct pci_bus * __devinit pci_scan_bus_parented(struct device *parent,
 	pci_add_resource(&resources, &ioport_resource);
 	pci_add_resource(&resources, &iomem_resource);
 	b = pci_create_root_bus(parent, bus, ops, sysdata, &resources);
-	if (b)
+	if (b) {
+		pci_bus_insert_busn_res(b, bus, 255);
 		b->subordinate = pci_scan_child_bus(b);
-	else
+		pci_bus_update_busn_res_end(b, b->subordinate);
+	} else
 		pci_free_resource_list(&resources);
 	return b;
 }
@@ -1712,7 +1731,10 @@ struct pci_bus * __devinit pci_scan_bus(int bus, struct pci_ops *ops,
 	pci_add_resource(&resources, &iomem_resource);
 	b = pci_create_root_bus(NULL, bus, ops, sysdata, &resources);
 	if (b) {
+		pci_bus_insert_busn_res(b, bus, 255);
 		b->subordinate = pci_scan_child_bus(b);
+		pci_bus_update_busn_res_end(b, b->subordinate);
+
 		pci_bus_add_devices(b);
 	} else {
 		pci_free_resource_list(&resources);
diff --git a/drivers/pci/remove.c b/drivers/pci/remove.c
index bd70f23..8056e6a 100644
--- a/drivers/pci/remove.c
+++ b/drivers/pci/remove.c
@@ -68,6 +68,7 @@ void pci_remove_bus(struct pci_bus *pci_bus)
 
 	down_write(&pci_bus_sem);
 	list_del(&pci_bus->node);
+	pci_bus_release_busn_res(pci_bus);
 	up_write(&pci_bus_sem);
 	if (!pci_bus->is_added)
 		return;
diff --git a/include/linux/pci.h b/include/linux/pci.h
index 3da935c..d5b6786 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -668,6 +668,10 @@ struct pci_bus *pci_create_root_bus(struct device *parent, int bus,
 void pci_bus_insert_busn_res(struct pci_bus *b, int bus, int busmax);
 void pci_bus_update_busn_res_end(struct pci_bus *b, int busmax);
 void pci_bus_release_busn_res(struct pci_bus *b);
+struct pci_bus * __devinit pci_scan_root_bus_max(struct device *parent, int bus,
+					     int busmax, struct pci_ops *ops,
+					     void *sysdata,
+					     struct list_head *resources);
 struct pci_bus * __devinit pci_scan_root_bus(struct device *parent, int bus,
 					     struct pci_ops *ops, void *sysdata,
 					     struct list_head *resources);
-- 
1.7.7

[PATCH 03/22] PCI: Add busn_res tracking in core

[Yinghai Lu]

update pci_scan_root_bus, and pci_scan_bus to insert root bus busn into
iobusn_resource tree.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
---
 drivers/pci/probe.c  |   30 ++++++++++++++++++++++++++----
 drivers/pci/remove.c |    1 +
 include/linux/pci.h  |    4 ++++
 3 files changed, 31 insertions(+), 4 deletions(-)

diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index 480670f..33cc54e 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -1669,8 +1669,9 @@ void pci_bus_release_busn_res(struct pci_bus *b)
 			res, ret ? "can not be" : "is");
 }
 
-struct pci_bus * __devinit pci_scan_root_bus(struct device *parent, int bus,
-		struct pci_ops *ops, void *sysdata, struct list_head *resources)
+struct pci_bus * __devinit pci_scan_root_bus_max(struct device *parent, int bus,
+		int bus_max, struct pci_ops *ops, void *sysdata,
+		struct list_head *resources)
 {
 	struct pci_bus *b;
 
@@ -1678,10 +1679,26 @@ struct pci_bus * __devinit pci_scan_root_bus(struct device *parent, int bus,
 	if (!b)
 		return NULL;
 
+	pci_bus_insert_busn_res(b, bus, bus_max);
 	b->subordinate = pci_scan_child_bus(b);
 	pci_bus_add_devices(b);
 	return b;
 }
+EXPORT_SYMBOL(pci_scan_root_bus_max);
+
+struct pci_bus * __devinit pci_scan_root_bus(struct device *parent, int bus,
+		struct pci_ops *ops, void *sysdata,
+		struct list_head *resources)
+{
+	struct pci_bus *b;
+
+	b = pci_scan_root_bus_max(parent, bus, 255, ops, sysdata, resources);
+
+	if (b)
+		pci_bus_update_busn_res_end(b, b->subordinate);
+
+	return b;
+}
 EXPORT_SYMBOL(pci_scan_root_bus);
 
 /* Deprecated; use pci_scan_root_bus() instead */
@@ -1694,9 +1711,11 @@ struct pci_bus * __devinit pci_scan_bus_parented(struct device *parent,
 	pci_add_resource(&resources, &ioport_resource);
 	pci_add_resource(&resources, &iomem_resource);
 	b = pci_create_root_bus(parent, bus, ops, sysdata, &resources);
-	if (b)
+	if (b) {
+		pci_bus_insert_busn_res(b, bus, 255);
 		b->subordinate = pci_scan_child_bus(b);
-	else
+		pci_bus_update_busn_res_end(b, b->subordinate);
+	} else
 		pci_free_resource_list(&resources);
 	return b;
 }
@@ -1712,7 +1731,10 @@ struct pci_bus * __devinit pci_scan_bus(int bus, struct pci_ops *ops,
 	pci_add_resource(&resources, &iomem_resource);
 	b = pci_create_root_bus(NULL, bus, ops, sysdata, &resources);
 	if (b) {
+		pci_bus_insert_busn_res(b, bus, 255);
 		b->subordinate = pci_scan_child_bus(b);
+		pci_bus_update_busn_res_end(b, b->subordinate);
+
 		pci_bus_add_devices(b);
 	} else {
 		pci_free_resource_list(&resources);
diff --git a/drivers/pci/remove.c b/drivers/pci/remove.c
index bd70f23..8056e6a 100644
--- a/drivers/pci/remove.c
+++ b/drivers/pci/remove.c
@@ -68,6 +68,7 @@ void pci_remove_bus(struct pci_bus *pci_bus)
 
 	down_write(&pci_bus_sem);
 	list_del(&pci_bus->node);
+	pci_bus_release_busn_res(pci_bus);
 	up_write(&pci_bus_sem);
 	if (!pci_bus->is_added)
 		return;
diff --git a/include/linux/pci.h b/include/linux/pci.h
index 3da935c..d5b6786 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -668,6 +668,10 @@ struct pci_bus *pci_create_root_bus(struct device *parent, int bus,
 void pci_bus_insert_busn_res(struct pci_bus *b, int bus, int busmax);
 void pci_bus_update_busn_res_end(struct pci_bus *b, int busmax);
 void pci_bus_release_busn_res(struct pci_bus *b);
+struct pci_bus * __devinit pci_scan_root_bus_max(struct device *parent, int bus,
+					     int busmax, struct pci_ops *ops,
+					     void *sysdata,
+					     struct list_head *resources);
 struct pci_bus * __devinit pci_scan_root_bus(struct device *parent, int bus,
 					     struct pci_ops *ops, void *sysdata,
 					     struct list_head *resources);
-- 
1.7.7

[PATCH 04/22] PCI, x86: Register busn_res for root buses

[Yinghai Lu]

update x86_pci_root_bus_resources() to get bus_max for non-acpi case.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
---
 arch/x86/include/asm/topology.h |    3 ++-
 arch/x86/pci/acpi.c             |    8 +++++---
 arch/x86/pci/bus_numa.c         |    8 +++++++-
 arch/x86/pci/common.c           |   11 +++++++----
 4 files changed, 21 insertions(+), 9 deletions(-)

diff --git a/arch/x86/include/asm/topology.h b/arch/x86/include/asm/topology.h
index b9676ae..ad4060e 100644
--- a/arch/x86/include/asm/topology.h
+++ b/arch/x86/include/asm/topology.h
@@ -172,7 +172,8 @@ static inline void arch_fix_phys_package_id(int num, u32 slot)
 }
 
 struct pci_bus;
-void x86_pci_root_bus_resources(int bus, struct list_head *resources);
+void x86_pci_root_bus_resources(int bus, int *bus_max,
+				struct list_head *resources);
 
 #ifdef CONFIG_SMP
 #define mc_capable()	((boot_cpu_data.x86_max_cores > 1) && \
diff --git a/arch/x86/pci/acpi.c b/arch/x86/pci/acpi.c
index daa4249..b25b5b1 100644
--- a/arch/x86/pci/acpi.c
+++ b/arch/x86/pci/acpi.c
@@ -348,6 +348,7 @@ struct pci_bus * __devinit pci_acpi_scan_root(struct acpi_pci_root *root)
 	struct acpi_device *device = root->device;
 	int domain = root->segment;
 	int busnum = root->secondary.start;
+	int busmax = root->secondary.end;
 	LIST_HEAD(resources);
 	struct pci_bus *bus;
 	struct pci_sysdata *sd;
@@ -410,12 +411,13 @@ struct pci_bus * __devinit pci_acpi_scan_root(struct acpi_pci_root *root)
 		 * defaults or native bridge info if we're ignoring _CRS.
 		 */
 		if (!pci_use_crs)
-			x86_pci_root_bus_resources(busnum, &resources);
+			x86_pci_root_bus_resources(busnum, &busmax, &resources);
 		bus = pci_create_root_bus(NULL, busnum, &pci_root_ops, sd,
 					  &resources);
-		if (bus)
+		if (bus) {
+			pci_bus_insert_busn_res(bus, busnum, busmax);
 			bus->subordinate = pci_scan_child_bus(bus);
-		else
+		} else
 			pci_free_resource_list(&resources);
 	}
 
diff --git a/arch/x86/pci/bus_numa.c b/arch/x86/pci/bus_numa.c
index fd3f655..5213cd8 100644
--- a/arch/x86/pci/bus_numa.c
+++ b/arch/x86/pci/bus_numa.c
@@ -7,7 +7,8 @@
 int pci_root_num;
 struct pci_root_info pci_root_info[PCI_ROOT_NR];
 
-void x86_pci_root_bus_resources(int bus, struct list_head *resources)
+void x86_pci_root_bus_resources(int bus, int *bus_max,
+				struct list_head *resources)
 {
 	int i;
 	int j;
@@ -28,6 +29,7 @@ void x86_pci_root_bus_resources(int bus, struct list_head *resources)
 	       bus);
 
 	info = &pci_root_info[i];
+	*bus_max = info->bus_max;
 	for (j = 0; j < info->res_num; j++) {
 		struct resource *res;
 		struct resource *root;
@@ -51,6 +53,10 @@ default_resources:
 	printk(KERN_DEBUG "PCI: root bus %02x: using default resources\n", bus);
 	pci_add_resource(resources, &ioport_resource);
 	pci_add_resource(resources, &iomem_resource);
+	if (!bus)
+		*bus_max = 0xff;
+	else if (!*bus_max)
+		*bus_max = bus;
 }
 
 void __devinit update_res(struct pci_root_info *info, resource_size_t start,
diff --git a/arch/x86/pci/common.c b/arch/x86/pci/common.c
index 323481e..ce0aefc 100644
--- a/arch/x86/pci/common.c
+++ b/arch/x86/pci/common.c
@@ -433,6 +433,7 @@ struct pci_bus * __devinit pcibios_scan_root(int busnum)
 	LIST_HEAD(resources);
 	struct pci_bus *bus = NULL;
 	struct pci_sysdata *sd;
+	int bus_max;
 
 	while ((bus = pci_find_next_bus(bus)) != NULL) {
 		if (bus->number == busnum) {
@@ -454,8 +455,9 @@ struct pci_bus * __devinit pcibios_scan_root(int busnum)
 	sd->node = get_mp_bus_to_node(busnum);
 
 	printk(KERN_DEBUG "PCI: Probing PCI hardware (bus %02x)\n", busnum);
-	x86_pci_root_bus_resources(busnum, &resources);
-	bus = pci_scan_root_bus(NULL, busnum, &pci_root_ops, sd, &resources);
+	x86_pci_root_bus_resources(busnum, &bus_max, &resources);
+	bus = pci_scan_root_bus_max(NULL, busnum, bus_max, &pci_root_ops, sd,
+				&resources);
 	if (!bus) {
 		pci_free_resource_list(&resources);
 		kfree(sd);
@@ -643,6 +645,7 @@ struct pci_bus * __devinit pci_scan_bus_on_node(int busno, struct pci_ops *ops,
 	LIST_HEAD(resources);
 	struct pci_bus *bus = NULL;
 	struct pci_sysdata *sd;
+	int bus_max;
 
 	/*
 	 * Allocate per-root-bus (not per bus) arch-specific data.
@@ -655,8 +658,8 @@ struct pci_bus * __devinit pci_scan_bus_on_node(int busno, struct pci_ops *ops,
 		return NULL;
 	}
 	sd->node = node;
-	x86_pci_root_bus_resources(busno, &resources);
-	bus = pci_scan_root_bus(NULL, busno, ops, sd, &resources);
+	x86_pci_root_bus_resources(busno, &bus_max, &resources);
+	bus = pci_scan_root_bus_max(NULL, busno, bus_max, ops, sd, &resources);
 	if (!bus) {
 		pci_free_resource_list(&resources);
 		kfree(sd);
-- 
1.7.7

[PATCH 04/22] PCI, x86: Register busn_res for root buses

[Yinghai Lu]

update x86_pci_root_bus_resources() to get bus_max for non-acpi case.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
---
 arch/x86/include/asm/topology.h |    3 ++-
 arch/x86/pci/acpi.c             |    8 +++++---
 arch/x86/pci/bus_numa.c         |    8 +++++++-
 arch/x86/pci/common.c           |   11 +++++++----
 4 files changed, 21 insertions(+), 9 deletions(-)

diff --git a/arch/x86/include/asm/topology.h b/arch/x86/include/asm/topology.h
index b9676ae..ad4060e 100644
--- a/arch/x86/include/asm/topology.h
+++ b/arch/x86/include/asm/topology.h
@@ -172,7 +172,8 @@ static inline void arch_fix_phys_package_id(int num, u32 slot)
 }
 
 struct pci_bus;
-void x86_pci_root_bus_resources(int bus, struct list_head *resources);
+void x86_pci_root_bus_resources(int bus, int *bus_max,
+				struct list_head *resources);
 
 #ifdef CONFIG_SMP
 #define mc_capable()	((boot_cpu_data.x86_max_cores > 1) && \
diff --git a/arch/x86/pci/acpi.c b/arch/x86/pci/acpi.c
index daa4249..b25b5b1 100644
--- a/arch/x86/pci/acpi.c
+++ b/arch/x86/pci/acpi.c
@@ -348,6 +348,7 @@ struct pci_bus * __devinit pci_acpi_scan_root(struct acpi_pci_root *root)
 	struct acpi_device *device = root->device;
 	int domain = root->segment;
 	int busnum = root->secondary.start;
+	int busmax = root->secondary.end;
 	LIST_HEAD(resources);
 	struct pci_bus *bus;
 	struct pci_sysdata *sd;
@@ -410,12 +411,13 @@ struct pci_bus * __devinit pci_acpi_scan_root(struct acpi_pci_root *root)
 		 * defaults or native bridge info if we're ignoring _CRS.
 		 */
 		if (!pci_use_crs)
-			x86_pci_root_bus_resources(busnum, &resources);
+			x86_pci_root_bus_resources(busnum, &busmax, &resources);
 		bus = pci_create_root_bus(NULL, busnum, &pci_root_ops, sd,
 					  &resources);
-		if (bus)
+		if (bus) {
+			pci_bus_insert_busn_res(bus, busnum, busmax);
 			bus->subordinate = pci_scan_child_bus(bus);
-		else
+		} else
 			pci_free_resource_list(&resources);
 	}
 
diff --git a/arch/x86/pci/bus_numa.c b/arch/x86/pci/bus_numa.c
index fd3f655..5213cd8 100644
--- a/arch/x86/pci/bus_numa.c
+++ b/arch/x86/pci/bus_numa.c
@@ -7,7 +7,8 @@
 int pci_root_num;
 struct pci_root_info pci_root_info[PCI_ROOT_NR];
 
-void x86_pci_root_bus_resources(int bus, struct list_head *resources)
+void x86_pci_root_bus_resources(int bus, int *bus_max,
+				struct list_head *resources)
 {
 	int i;
 	int j;
@@ -28,6 +29,7 @@ void x86_pci_root_bus_resources(int bus, struct list_head *resources)
 	       bus);
 
 	info = &pci_root_info[i];
+	*bus_max = info->bus_max;
 	for (j = 0; j < info->res_num; j++) {
 		struct resource *res;
 		struct resource *root;
@@ -51,6 +53,10 @@ default_resources:
 	printk(KERN_DEBUG "PCI: root bus %02x: using default resources\n", bus);
 	pci_add_resource(resources, &ioport_resource);
 	pci_add_resource(resources, &iomem_resource);
+	if (!bus)
+		*bus_max = 0xff;
+	else if (!*bus_max)
+		*bus_max = bus;
 }
 
 void __devinit update_res(struct pci_root_info *info, resource_size_t start,
diff --git a/arch/x86/pci/common.c b/arch/x86/pci/common.c
index 323481e..ce0aefc 100644
--- a/arch/x86/pci/common.c
+++ b/arch/x86/pci/common.c
@@ -433,6 +433,7 @@ struct pci_bus * __devinit pcibios_scan_root(int busnum)
 	LIST_HEAD(resources);
 	struct pci_bus *bus = NULL;
 	struct pci_sysdata *sd;
+	int bus_max;
 
 	while ((bus = pci_find_next_bus(bus)) != NULL) {
 		if (bus->number == busnum) {
@@ -454,8 +455,9 @@ struct pci_bus * __devinit pcibios_scan_root(int busnum)
 	sd->node = get_mp_bus_to_node(busnum);
 
 	printk(KERN_DEBUG "PCI: Probing PCI hardware (bus %02x)\n", busnum);
-	x86_pci_root_bus_resources(busnum, &resources);
-	bus = pci_scan_root_bus(NULL, busnum, &pci_root_ops, sd, &resources);
+	x86_pci_root_bus_resources(busnum, &bus_max, &resources);
+	bus = pci_scan_root_bus_max(NULL, busnum, bus_max, &pci_root_ops, sd,
+				&resources);
 	if (!bus) {
 		pci_free_resource_list(&resources);
 		kfree(sd);
@@ -643,6 +645,7 @@ struct pci_bus * __devinit pci_scan_bus_on_node(int busno, struct pci_ops *ops,
 	LIST_HEAD(resources);
 	struct pci_bus *bus = NULL;
 	struct pci_sysdata *sd;
+	int bus_max;
 
 	/*
 	 * Allocate per-root-bus (not per bus) arch-specific data.
@@ -655,8 +658,8 @@ struct pci_bus * __devinit pci_scan_bus_on_node(int busno, struct pci_ops *ops,
 		return NULL;
 	}
 	sd->node = node;
-	x86_pci_root_bus_resources(busno, &resources);
-	bus = pci_scan_root_bus(NULL, busno, ops, sd, &resources);
+	x86_pci_root_bus_resources(busno, &bus_max, &resources);
+	bus = pci_scan_root_bus_max(NULL, busno, bus_max, ops, sd, &resources);
 	if (!bus) {
 		pci_free_resource_list(&resources);
 		kfree(sd);
-- 
1.7.7

[PATCH 05/22] PCI, ia64: Register busn_res for root buses

[Yinghai Lu]

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: linux-ia64@vger.kernel.org
---
 arch/ia64/pci/pci.c |    2 ++
 1 files changed, 2 insertions(+), 0 deletions(-)

diff --git a/arch/ia64/pci/pci.c b/arch/ia64/pci/pci.c
index f82f5d4..936b2f1 100644
--- a/arch/ia64/pci/pci.c
+++ b/arch/ia64/pci/pci.c
@@ -331,6 +331,7 @@ pci_acpi_scan_root(struct acpi_pci_root *root)
 	struct acpi_device *device = root->device;
 	int domain = root->segment;
 	int bus = root->secondary.start;
+	int busmax = root->secondary.end;
 	struct pci_controller *controller;
 	unsigned int windows = 0;
 	struct pci_root_info info;
@@ -384,6 +385,7 @@ pci_acpi_scan_root(struct acpi_pci_root *root)
 		return NULL;
 	}
 
+	pci_bus_insert_busn_res(pbus, busnum, busmax);
 	pbus->subordinate = pci_scan_child_bus(pbus);
 	return pbus;
 
-- 
1.7.7

[PATCH 05/22] PCI, ia64: Register busn_res for root buses

[Yinghai Lu]

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: linux-ia64@vger.kernel.org
---
 arch/ia64/pci/pci.c |    2 ++
 1 files changed, 2 insertions(+), 0 deletions(-)

diff --git a/arch/ia64/pci/pci.c b/arch/ia64/pci/pci.c
index f82f5d4..936b2f1 100644
--- a/arch/ia64/pci/pci.c
+++ b/arch/ia64/pci/pci.c
@@ -331,6 +331,7 @@ pci_acpi_scan_root(struct acpi_pci_root *root)
 	struct acpi_device *device = root->device;
 	int domain = root->segment;
 	int bus = root->secondary.start;
+	int busmax = root->secondary.end;
 	struct pci_controller *controller;
 	unsigned int windows = 0;
 	struct pci_root_info info;
@@ -384,6 +385,7 @@ pci_acpi_scan_root(struct acpi_pci_root *root)
 		return NULL;
 	}
 
+	pci_bus_insert_busn_res(pbus, busnum, busmax);
 	pbus->subordinate = pci_scan_child_bus(pbus);
 	return pbus;
 
-- 
1.7.7

[PATCH 06/22] PCI, sparc: Register busn_res for root buses

[Yinghai Lu]

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: sparclinux@vger.kernel.org
---
 arch/sparc/kernel/pci.c |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)

diff --git a/arch/sparc/kernel/pci.c b/arch/sparc/kernel/pci.c
index bb8bc2e..83881df9 100644
--- a/arch/sparc/kernel/pci.c
+++ b/arch/sparc/kernel/pci.c
@@ -703,6 +703,7 @@ struct pci_bus * __devinit pci_scan_one_pbm(struct pci_pbm_info *pbm,
 	}
 	bus->secondary = pbm->pci_first_busno;
 	bus->subordinate = pbm->pci_last_busno;
+	pci_bus_insert_busn_res(bus, pbm->pci_first_busno, pbm->pci_last_busno);
 
 	pci_of_scan_bus(pbm, node, bus);
 	pci_bus_add_devices(bus);
-- 
1.7.7

[PATCH 06/22] PCI, sparc: Register busn_res for root buses

[Yinghai Lu]

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: sparclinux@vger.kernel.org
---
 arch/sparc/kernel/pci.c |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)

diff --git a/arch/sparc/kernel/pci.c b/arch/sparc/kernel/pci.c
index bb8bc2e..83881df9 100644
--- a/arch/sparc/kernel/pci.c
+++ b/arch/sparc/kernel/pci.c
@@ -703,6 +703,7 @@ struct pci_bus * __devinit pci_scan_one_pbm(struct pci_pbm_info *pbm,
 	}
 	bus->secondary = pbm->pci_first_busno;
 	bus->subordinate = pbm->pci_last_busno;
+	pci_bus_insert_busn_res(bus, pbm->pci_first_busno, pbm->pci_last_busno);
 
 	pci_of_scan_bus(pbm, node, bus);
 	pci_bus_add_devices(bus);
-- 
1.7.7

[PATCH 07/22] PCI, powerpc: Register busn_res for root buses

[Yinghai Lu]

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: linuxppc-dev@lists.ozlabs.org
---
 arch/powerpc/kernel/pci-common.c |    7 ++++++-
 1 files changed, 6 insertions(+), 1 deletions(-)

diff --git a/arch/powerpc/kernel/pci-common.c b/arch/powerpc/kernel/pci-common.c
index cce98d7..501f29b 100644
--- a/arch/powerpc/kernel/pci-common.c
+++ b/arch/powerpc/kernel/pci-common.c
@@ -1732,6 +1732,8 @@ void __devinit pcibios_scan_phb(struct pci_controller *hose)
 	bus->secondary = hose->first_busno;
 	hose->bus = bus;
 
+	pci_bus_insert_busn_res(bus, hose->first_busno, hose->last_busno);
+
 	/* Get probe mode and perform scan */
 	mode = PCI_PROBE_NORMAL;
 	if (node && ppc_md.pci_probe_mode)
@@ -1742,8 +1744,11 @@ void __devinit pcibios_scan_phb(struct pci_controller *hose)
 		of_scan_bus(node, bus);
 	}
 
-	if (mode == PCI_PROBE_NORMAL)
+	if (mode == PCI_PROBE_NORMAL) {
+		pci_bus_update_busn_res_end(bus, 255);
 		hose->last_busno = bus->subordinate = pci_scan_child_bus(bus);
+		pci_bus_update_busn_res_end(bus, bus->subordinate);
+	}
 
 	/* Platform gets a chance to do some global fixups before
 	 * we proceed to resource allocation
-- 
1.7.7

[PATCH 07/22] PCI, powerpc: Register busn_res for root buses

[Yinghai Lu]

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: linuxppc-dev@lists.ozlabs.org
---
 arch/powerpc/kernel/pci-common.c |    7 ++++++-
 1 files changed, 6 insertions(+), 1 deletions(-)

diff --git a/arch/powerpc/kernel/pci-common.c b/arch/powerpc/kernel/pci-common.c
index cce98d7..501f29b 100644
--- a/arch/powerpc/kernel/pci-common.c
+++ b/arch/powerpc/kernel/pci-common.c
@@ -1732,6 +1732,8 @@ void __devinit pcibios_scan_phb(struct pci_controller *hose)
 	bus->secondary = hose->first_busno;
 	hose->bus = bus;
 
+	pci_bus_insert_busn_res(bus, hose->first_busno, hose->last_busno);
+
 	/* Get probe mode and perform scan */
 	mode = PCI_PROBE_NORMAL;
 	if (node && ppc_md.pci_probe_mode)
@@ -1742,8 +1744,11 @@ void __devinit pcibios_scan_phb(struct pci_controller *hose)
 		of_scan_bus(node, bus);
 	}
 
-	if (mode == PCI_PROBE_NORMAL)
+	if (mode == PCI_PROBE_NORMAL) {
+		pci_bus_update_busn_res_end(bus, 255);
 		hose->last_busno = bus->subordinate = pci_scan_child_bus(bus);
+		pci_bus_update_busn_res_end(bus, bus->subordinate);
+	}
 
 	/* Platform gets a chance to do some global fixups before
 	 * we proceed to resource allocation
-- 
1.7.7

[PATCH 08/22] PCI, parisc: Register busn_res for root buses

[Yinghai Lu]

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Cc: Kyle McMartin <kyle@mcmartin.ca>
Cc: Helge Deller <deller@gmx.de>
Cc: linux-parisc@vger.kernel.org
---
 drivers/parisc/dino.c    |    2 ++
 drivers/parisc/lba_pci.c |    3 +++
 2 files changed, 5 insertions(+), 0 deletions(-)

diff --git a/drivers/parisc/dino.c b/drivers/parisc/dino.c
index 7ff10c1..3f2e203 100644
--- a/drivers/parisc/dino.c
+++ b/drivers/parisc/dino.c
@@ -1014,7 +1014,9 @@ static int __init dino_probe(struct parisc_device *dev)
 		return 0;
 	}
 
+	pci_bus_insert_busn_res(bus, dino_current_bus, 255);
 	bus->subordinate = pci_scan_child_bus(bus);
+	pci_bus_update_busn_res_end(bus, bus->subordinate);
 
 	/* This code *depends* on scanning being single threaded
 	 * if it isn't, this global bus number count will fail
diff --git a/drivers/parisc/lba_pci.c b/drivers/parisc/lba_pci.c
index d5f3d75..b58bf8b 100644
--- a/drivers/parisc/lba_pci.c
+++ b/drivers/parisc/lba_pci.c
@@ -1531,6 +1531,9 @@ lba_driver_probe(struct parisc_device *dev)
 		return 0;
 	}
 
+	pci_bus_insert_busn_res(lba_bus, lba_dev->hba.bus_num.start,
+				lba_dev->hba.bus_num.end);
+
 	lba_bus->subordinate = pci_scan_child_bus(lba_bus);
 
 	/* This is in lieu of calling pci_assign_unassigned_resources() */
-- 
1.7.7

[PATCH 08/22] PCI, parisc: Register busn_res for root buses

[Yinghai Lu]

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Cc: Kyle McMartin <kyle@mcmartin.ca>
Cc: Helge Deller <deller@gmx.de>
Cc: linux-parisc@vger.kernel.org
---
 drivers/parisc/dino.c    |    2 ++
 drivers/parisc/lba_pci.c |    3 +++
 2 files changed, 5 insertions(+), 0 deletions(-)

diff --git a/drivers/parisc/dino.c b/drivers/parisc/dino.c
index 7ff10c1..3f2e203 100644
--- a/drivers/parisc/dino.c
+++ b/drivers/parisc/dino.c
@@ -1014,7 +1014,9 @@ static int __init dino_probe(struct parisc_device *dev)
 		return 0;
 	}
 
+	pci_bus_insert_busn_res(bus, dino_current_bus, 255);
 	bus->subordinate = pci_scan_child_bus(bus);
+	pci_bus_update_busn_res_end(bus, bus->subordinate);
 
 	/* This code *depends* on scanning being single threaded
 	 * if it isn't, this global bus number count will fail
diff --git a/drivers/parisc/lba_pci.c b/drivers/parisc/lba_pci.c
index d5f3d75..b58bf8b 100644
--- a/drivers/parisc/lba_pci.c
+++ b/drivers/parisc/lba_pci.c
@@ -1531,6 +1531,9 @@ lba_driver_probe(struct parisc_device *dev)
 		return 0;
 	}
 
+	pci_bus_insert_busn_res(lba_bus, lba_dev->hba.bus_num.start,
+				lba_dev->hba.bus_num.end);
+
 	lba_bus->subordinate = pci_scan_child_bus(lba_bus);
 
 	/* This is in lieu of calling pci_assign_unassigned_resources() */
-- 
1.7.7

[PATCH 09/22] PCI: Add pci_bus_extend/shrink_top()

[Yinghai Lu]

extend or shrink bus and parent buses top (subordinate)

extended range is verified safe range, and stop at recorded parent_res.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
---
 drivers/pci/probe.c |   36 ++++++++++++++++++++++++++++++++++++
 1 files changed, 36 insertions(+), 0 deletions(-)

diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index 33cc54e..2a7047a 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -624,6 +624,42 @@ static void pci_fixup_parent_subordinate_busnr(struct pci_bus *child, int max)
 	}
 }
 
+static void __devinit pci_bus_update_top(struct pci_bus *parent,
+		 long size, struct resource *parent_res)
+{
+	struct resource *res;
+
+	if (!size)
+		return;
+
+	while (parent) {
+		res = &parent->busn_res;
+		if (res == parent_res)
+			break;
+		res->end += size;
+		parent->subordinate += size;
+		pci_write_config_byte(parent->self, PCI_SUBORDINATE_BUS,
+					 parent->subordinate);
+		dev_printk(KERN_DEBUG, &parent->dev,
+				"busn_res: %s %02lx to %pR\n",
+				(size > 0) ? "extended" : "shrunk",
+				abs(size), res);
+		parent = parent->parent;
+	}
+}
+
+static void __devinit pci_bus_extend_top(struct pci_bus *parent,
+		 long size, struct resource *parent_res)
+{
+	pci_bus_update_top(parent, size, parent_res);
+}
+
+static void __devinit pci_bus_shrink_top(struct pci_bus *parent,
+		 long size, struct resource *parent_res)
+{
+	pci_bus_update_top(parent, -size, parent_res);
+}
+
 /*
  * If it's a bridge, configure it and scan the bus behind it.
  * For CardBus bridges, we don't scan behind as the devices will
-- 
1.7.7

[PATCH 09/22] PCI: Add pci_bus_extend/shrink_top()

[Yinghai Lu]

extend or shrink bus and parent buses top (subordinate)

extended range is verified safe range, and stop at recorded parent_res.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
---
 drivers/pci/probe.c |   36 ++++++++++++++++++++++++++++++++++++
 1 files changed, 36 insertions(+), 0 deletions(-)

diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index 33cc54e..2a7047a 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -624,6 +624,42 @@ static void pci_fixup_parent_subordinate_busnr(struct pci_bus *child, int max)
 	}
 }
 
+static void __devinit pci_bus_update_top(struct pci_bus *parent,
+		 long size, struct resource *parent_res)
+{
+	struct resource *res;
+
+	if (!size)
+		return;
+
+	while (parent) {
+		res = &parent->busn_res;
+		if (res == parent_res)
+			break;
+		res->end += size;
+		parent->subordinate += size;
+		pci_write_config_byte(parent->self, PCI_SUBORDINATE_BUS,
+					 parent->subordinate);
+		dev_printk(KERN_DEBUG, &parent->dev,
+				"busn_res: %s %02lx to %pR\n",
+				(size > 0) ? "extended" : "shrunk",
+				abs(size), res);
+		parent = parent->parent;
+	}
+}
+
+static void __devinit pci_bus_extend_top(struct pci_bus *parent,
+		 long size, struct resource *parent_res)
+{
+	pci_bus_update_top(parent, size, parent_res);
+}
+
+static void __devinit pci_bus_shrink_top(struct pci_bus *parent,
+		 long size, struct resource *parent_res)
+{
+	pci_bus_update_top(parent, -size, parent_res);
+}
+
 /*
  * If it's a bridge, configure it and scan the bus behind it.
  * For CardBus bridges, we don't scan behind as the devices will
-- 
1.7.7

[PATCH 10/22] PCI: Probe safe range that we can use for unassigned bridge.

[Yinghai Lu]

Try to allocate from parent bus busn_res. if can not find any big enough, will try
to extend parent bus top. even the extending is through allocating, after allocating
will pad the range to parent buses top.

When extending happens, We will record the parent_res, so could use it as stopper
for really extend/shrink top later.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
---
 drivers/pci/probe.c |  110 +++++++++++++++++++++++++++++++++++++++++++++++++++
 1 files changed, 110 insertions(+), 0 deletions(-)

diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index 2a7047a..fcd9266 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -660,6 +660,116 @@ static void __devinit pci_bus_shrink_top(struct pci_bus *parent,
 	pci_bus_update_top(parent, -size, parent_res);
 }
 
+static resource_size_t __devinit find_res_top_free_size(struct resource *res)
+{
+	resource_size_t n_size;
+	struct resource tmp_res;
+
+	/*
+	 *   find out number below res->end, that we can use at first
+	 *	res->start can not be used.
+	 */
+	n_size = resource_size(res) - 1;
+	memset(&tmp_res, 0, sizeof(struct resource));
+	while (n_size > 0) {
+		int ret;
+
+		ret = allocate_resource(res, &tmp_res, n_size,
+			res->end - n_size + 1, res->end,
+			1, NULL, NULL);
+		if (ret == 0) {
+			release_resource(&tmp_res);
+			break;
+		}
+		n_size--;
+	}
+
+	return n_size;
+}
+
+static int __devinit pci_bridge_probe_busn_res(struct pci_bus *bus,
+			 struct pci_dev *dev, struct resource *busn_res,
+			 resource_size_t needed_size, struct resource **p)
+{
+	int ret = -ENOMEM;
+	resource_size_t n_size;
+	struct pci_bus *parent;
+	struct resource *parent_res = NULL;
+	resource_size_t tmp = bus->busn_res.end + 1;
+	int free_sz = -1;
+
+again:
+	/*
+	 * find bigest range in bus->busn_res that we can use in the middle
+	 *  and we can not use bus->busn_res.start.
+	 */
+	n_size = resource_size(&bus->busn_res) - 1;
+	memset(busn_res, 0, sizeof(struct resource));
+	dev_printk(KERN_DEBUG, &dev->dev,
+			"find free busn in busn_res: %pR\n", &bus->busn_res);
+	while (n_size >= needed_size) {
+		ret = allocate_resource(&bus->busn_res, busn_res, n_size,
+				bus->busn_res.start + 1, bus->busn_res.end,
+				1, NULL, NULL);
+		if (ret == 0) {
+			/* found one, prepare to return */
+			release_resource(busn_res);
+
+			return ret;
+		}
+		n_size--;
+	}
+
+	/* try extend the top of parent bus, find free under top af first */
+	if (free_sz < 0) {
+		free_sz = find_res_top_free_size(&bus->busn_res);
+		dev_printk(KERN_DEBUG, &dev->dev,
+			"found free busn %d in busn_res: %pR top\n",
+				free_sz, &bus->busn_res);
+	}
+	n_size = free_sz;
+
+	/* can not extend cross domain boundary */
+	if ((0xff - bus->busn_res.end) < (needed_size - n_size))
+		goto reduce_needed_size;
+
+	/* find exteded range */
+	memset(busn_res, 0, sizeof(struct resource));
+	parent = bus->parent;
+	while (parent) {
+		ret = allocate_resource(&parent->busn_res, busn_res,
+			 needed_size - n_size,
+			 tmp, tmp + needed_size - n_size - 1,
+			 1, NULL, NULL);
+		if (ret == 0)
+			break;
+		parent = parent->parent;
+	}
+
+reduce_needed_size:
+	if (ret != 0) {
+		needed_size--;
+		if (!needed_size)
+			return ret;
+
+		goto again;
+	}
+
+	/* save parent_res, we need it as stopper later */
+	parent_res = busn_res->parent;
+
+	/* prepare busn_res for return */
+	release_resource(busn_res);
+	busn_res->start -= n_size;
+
+	/* extend parent bus top*/
+	pci_bus_extend_top(bus, needed_size - n_size, parent_res);
+
+	*p = parent_res;
+
+	return ret;
+}
+
 /*
  * If it's a bridge, configure it and scan the bus behind it.
  * For CardBus bridges, we don't scan behind as the devices will
-- 
1.7.7

[PATCH 10/22] PCI: Probe safe range that we can use for unassigned bridge.

[Yinghai Lu]

Try to allocate from parent bus busn_res. if can not find any big enough, will try
to extend parent bus top. even the extending is through allocating, after allocating
will pad the range to parent buses top.

When extending happens, We will record the parent_res, so could use it as stopper
for really extend/shrink top later.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
---
 drivers/pci/probe.c |  110 +++++++++++++++++++++++++++++++++++++++++++++++++++
 1 files changed, 110 insertions(+), 0 deletions(-)

diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index 2a7047a..fcd9266 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -660,6 +660,116 @@ static void __devinit pci_bus_shrink_top(struct pci_bus *parent,
 	pci_bus_update_top(parent, -size, parent_res);
 }
 
+static resource_size_t __devinit find_res_top_free_size(struct resource *res)
+{
+	resource_size_t n_size;
+	struct resource tmp_res;
+
+	/*
+	 *   find out number below res->end, that we can use at first
+	 *	res->start can not be used.
+	 */
+	n_size = resource_size(res) - 1;
+	memset(&tmp_res, 0, sizeof(struct resource));
+	while (n_size > 0) {
+		int ret;
+
+		ret = allocate_resource(res, &tmp_res, n_size,
+			res->end - n_size + 1, res->end,
+			1, NULL, NULL);
+		if (ret == 0) {
+			release_resource(&tmp_res);
+			break;
+		}
+		n_size--;
+	}
+
+	return n_size;
+}
+
+static int __devinit pci_bridge_probe_busn_res(struct pci_bus *bus,
+			 struct pci_dev *dev, struct resource *busn_res,
+			 resource_size_t needed_size, struct resource **p)
+{
+	int ret = -ENOMEM;
+	resource_size_t n_size;
+	struct pci_bus *parent;
+	struct resource *parent_res = NULL;
+	resource_size_t tmp = bus->busn_res.end + 1;
+	int free_sz = -1;
+
+again:
+	/*
+	 * find bigest range in bus->busn_res that we can use in the middle
+	 *  and we can not use bus->busn_res.start.
+	 */
+	n_size = resource_size(&bus->busn_res) - 1;
+	memset(busn_res, 0, sizeof(struct resource));
+	dev_printk(KERN_DEBUG, &dev->dev,
+			"find free busn in busn_res: %pR\n", &bus->busn_res);
+	while (n_size >= needed_size) {
+		ret = allocate_resource(&bus->busn_res, busn_res, n_size,
+				bus->busn_res.start + 1, bus->busn_res.end,
+				1, NULL, NULL);
+		if (ret == 0) {
+			/* found one, prepare to return */
+			release_resource(busn_res);
+
+			return ret;
+		}
+		n_size--;
+	}
+
+	/* try extend the top of parent bus, find free under top af first */
+	if (free_sz < 0) {
+		free_sz = find_res_top_free_size(&bus->busn_res);
+		dev_printk(KERN_DEBUG, &dev->dev,
+			"found free busn %d in busn_res: %pR top\n",
+				free_sz, &bus->busn_res);
+	}
+	n_size = free_sz;
+
+	/* can not extend cross domain boundary */
+	if ((0xff - bus->busn_res.end) < (needed_size - n_size))
+		goto reduce_needed_size;
+
+	/* find exteded range */
+	memset(busn_res, 0, sizeof(struct resource));
+	parent = bus->parent;
+	while (parent) {
+		ret = allocate_resource(&parent->busn_res, busn_res,
+			 needed_size - n_size,
+			 tmp, tmp + needed_size - n_size - 1,
+			 1, NULL, NULL);
+		if (ret == 0)
+			break;
+		parent = parent->parent;
+	}
+
+reduce_needed_size:
+	if (ret != 0) {
+		needed_size--;
+		if (!needed_size)
+			return ret;
+
+		goto again;
+	}
+
+	/* save parent_res, we need it as stopper later */
+	parent_res = busn_res->parent;
+
+	/* prepare busn_res for return */
+	release_resource(busn_res);
+	busn_res->start -= n_size;
+
+	/* extend parent bus top*/
+	pci_bus_extend_top(bus, needed_size - n_size, parent_res);
+
+	*p = parent_res;
+
+	return ret;
+}
+
 /*
  * If it's a bridge, configure it and scan the bus behind it.
  * For CardBus bridges, we don't scan behind as the devices will
-- 
1.7.7

[PATCH 11/22] PCI: Strict checking of valid range for bridge

[Yinghai Lu]

children bridges busn range should be able to be allocated from parent bus range.

to avoid overlapping between sibling bridges on same bus.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
---
 drivers/pci/probe.c |   24 ++++++++++++++++++++++++
 1 files changed, 24 insertions(+), 0 deletions(-)

diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index fcd9266..ca80141 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -770,6 +770,30 @@ reduce_needed_size:
 	return ret;
 }
 
+static int __devinit pci_bridge_check_busn_broken(struct pci_bus *bus,
+				struct pci_dev *dev,
+				int secondary, int subordinate)
+{
+	int broken = 0;
+
+	struct resource busn_res;
+	int ret;
+
+	memset(&busn_res, 0, sizeof(struct resource));
+	dev_printk(KERN_DEBUG, &dev->dev,
+		 "check if busn %02x-%02x is in busn_res: %pR\n",
+		 secondary, subordinate, &bus->busn_res);
+	ret = allocate_resource(&bus->busn_res, &busn_res,
+			 (subordinate - secondary + 1),
+			 secondary, subordinate,
+			 1, NULL, NULL);
+	if (ret)
+		broken = 1;
+	else
+		release_resource(&busn_res);
+
+	return broken;
+}
 /*
  * If it's a bridge, configure it and scan the bus behind it.
  * For CardBus bridges, we don't scan behind as the devices will
-- 
1.7.7

[PATCH 11/22] PCI: Strict checking of valid range for bridge

[Yinghai Lu]

children bridges busn range should be able to be allocated from parent bus range.

to avoid overlapping between sibling bridges on same bus.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
---
 drivers/pci/probe.c |   24 ++++++++++++++++++++++++
 1 files changed, 24 insertions(+), 0 deletions(-)

diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index fcd9266..ca80141 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -770,6 +770,30 @@ reduce_needed_size:
 	return ret;
 }
 
+static int __devinit pci_bridge_check_busn_broken(struct pci_bus *bus,
+				struct pci_dev *dev,
+				int secondary, int subordinate)
+{
+	int broken = 0;
+
+	struct resource busn_res;
+	int ret;
+
+	memset(&busn_res, 0, sizeof(struct resource));
+	dev_printk(KERN_DEBUG, &dev->dev,
+		 "check if busn %02x-%02x is in busn_res: %pR\n",
+		 secondary, subordinate, &bus->busn_res);
+	ret = allocate_resource(&bus->busn_res, &busn_res,
+			 (subordinate - secondary + 1),
+			 secondary, subordinate,
+			 1, NULL, NULL);
+	if (ret)
+		broken = 1;
+	else
+		release_resource(&busn_res);
+
+	return broken;
+}
 /*
  * If it's a bridge, configure it and scan the bus behind it.
  * For CardBus bridges, we don't scan behind as the devices will
-- 
1.7.7

[PATCH 12/22] PCI: Allocate bus range instead of use max blindly

[Yinghai Lu]

every bus have extra busn_res, and linked them toghter to iobusn_resource.

when need to find usable bus number range, try probe from iobusn_resource tree.

To avoid falling to small hole in the middle, we try from 8 spare bus.
if can not find 8 or more in the middle, will try to append 8 on top later.
then if can not append, will try to find 7 from the middle, then will try to append 7 on top.
then if can not append, will try to find 6 from the middle...

for cardbus will only find 4 spare.

if extend from top, at last will shrink back to really needed range...

-v4: fix checking with pci rescan. Found by Bjorn.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
---
 drivers/pci/probe.c |  100 ++++++++++++++++++++++++++++++---------------------
 1 files changed, 59 insertions(+), 41 deletions(-)

diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index ca80141..bff571b 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -808,10 +808,11 @@ int __devinit pci_scan_bridge(struct pci_bus *bus, struct pci_dev *dev, int max,
 {
 	struct pci_bus *child;
 	int is_cardbus = (dev->hdr_type == PCI_HEADER_TYPE_CARDBUS);
-	u32 buses, i, j = 0;
+	u32 buses;
 	u16 bctl;
 	u8 primary, secondary, subordinate;
 	int broken = 0;
+	struct resource *parent_res = NULL;
 
 	pci_read_config_dword(dev, PCI_PRIMARY_BUS, &buses);
 	primary = buses & 0xFF;
@@ -823,10 +824,16 @@ int __devinit pci_scan_bridge(struct pci_bus *bus, struct pci_dev *dev, int max,
 
 	/* Check if setup is sensible at all */
 	if (!pass &&
-	    (primary != bus->number || secondary <= bus->number)) {
-		dev_dbg(&dev->dev, "bus configuration invalid, reconfiguring\n");
+	    (primary != bus->number || secondary <= bus->number))
 		broken = 1;
-	}
+
+	/* more strict checking */
+	if (!pass && !broken && !dev->subordinate)
+		broken = pci_bridge_check_busn_broken(bus, dev,
+						   secondary, subordinate);
+
+	if (broken)
+		dev_dbg(&dev->dev, "bus configuration invalid, reconfiguring\n");
 
 	/* Disable MasterAbortMode during probing to avoid reporting
 	   of bus errors (in some architectures) */ 
@@ -859,6 +866,8 @@ int __devinit pci_scan_bridge(struct pci_bus *bus, struct pci_dev *dev, int max,
 			child->primary = primary;
 			child->subordinate = subordinate;
 			child->bridge_ctl = bctl;
+
+			pci_bus_insert_busn_res(child, secondary, subordinate);
 		}
 
 		cmax = pci_scan_child_bus(child);
@@ -871,6 +880,11 @@ int __devinit pci_scan_bridge(struct pci_bus *bus, struct pci_dev *dev, int max,
 		 * We need to assign a number to this bus which we always
 		 * do in the second pass.
 		 */
+		long shrink_size;
+		struct resource busn_res;
+		int ret = -ENOMEM;
+		int old_max = max;
+
 		if (!pass) {
 			if (pcibios_assign_all_busses() || broken)
 				/* Temporarily disable forwarding of the
@@ -887,20 +901,43 @@ int __devinit pci_scan_bridge(struct pci_bus *bus, struct pci_dev *dev, int max,
 		/* Clear errors */
 		pci_write_config_word(dev, PCI_STATUS, 0xffff);
 
-		/* Prevent assigning a bus number that already exists.
-		 * This can happen when a bridge is hot-plugged, so in
-		 * this case we only re-scan this bus. */
-		child = pci_find_bus(pci_domain_nr(bus), max+1);
-		if (!child) {
-			child = pci_add_new_bus(bus, dev, ++max);
-			if (!child)
-				goto out;
+		if (dev->subordinate) {
+			/* We get here only for cardbus */
+			child = dev->subordinate;
+			if  (!is_cardbus)
+				dev_warn(&dev->dev,
+				 "rescan scaned bridge as broken one again ?");
+
+			goto out;
 		}
+		/*
+		 * For CardBus bridges, we leave 4 bus numbers
+		 * as cards with a PCI-to-PCI bridge can be
+		 * inserted later.
+		 * other just allocate 8 bus to avoid we fall into
+		 *  small hole in the middle.
+		 */
+		ret = pci_bridge_probe_busn_res(bus, dev, &busn_res,
+				is_cardbus ? (CARDBUS_RESERVE_BUSNR + 1) : 8,
+				&parent_res);
+
+		if (ret != 0)
+			goto out;
+
+		child = pci_add_new_bus(bus, dev, busn_res.start);
+		if (!child)
+			goto out;
+
+		child->subordinate = busn_res.end;
+		pci_bus_insert_busn_res(child, busn_res.start, busn_res.end);
+
 		buses = (buses & 0xff000000)
 		      | ((unsigned int)(child->primary)     <<  0)
 		      | ((unsigned int)(child->secondary)   <<  8)
 		      | ((unsigned int)(child->subordinate) << 16);
 
+		max = child->subordinate;
+
 		/*
 		 * yenta.c forces a secondary latency timer of 176.
 		 * Copy that behaviour here.
@@ -931,43 +968,24 @@ int __devinit pci_scan_bridge(struct pci_bus *bus, struct pci_dev *dev, int max,
 			 * the real value of max.
 			 */
 			pci_fixup_parent_subordinate_busnr(child, max);
+
 		} else {
-			/*
-			 * For CardBus bridges, we leave 4 bus numbers
-			 * as cards with a PCI-to-PCI bridge can be
-			 * inserted later.
-			 */
-			for (i=0; i<CARDBUS_RESERVE_BUSNR; i++) {
-				struct pci_bus *parent = bus;
-				if (pci_find_bus(pci_domain_nr(bus),
-							max+i+1))
-					break;
-				while (parent->parent) {
-					if ((!pcibios_assign_all_busses()) &&
-					    (parent->subordinate > max) &&
-					    (parent->subordinate <= max+i)) {
-						j = 1;
-					}
-					parent = parent->parent;
-				}
-				if (j) {
-					/*
-					 * Often, there are two cardbus bridges
-					 * -- try to leave one valid bus number
-					 * for each one.
-					 */
-					i /= 2;
-					break;
-				}
-			}
-			max += i;
 			pci_fixup_parent_subordinate_busnr(child, max);
 		}
 		/*
 		 * Set the subordinate bus number to its real value.
 		 */
+		shrink_size = child->subordinate - max;
 		child->subordinate = max;
 		pci_write_config_byte(dev, PCI_SUBORDINATE_BUS, max);
+		pci_bus_update_busn_res_end(child, max);
+
+		/* shrink some back, if we extend top before */
+		if (!is_cardbus && (shrink_size > 0) && parent_res)
+			pci_bus_shrink_top(bus, shrink_size, parent_res);
+
+		if (old_max > max)
+			max = old_max;
 	}
 
 	sprintf(child->name,
-- 
1.7.7

[PATCH 13/22] PCI: kill pci_fixup_parent_subordinate_busnr()

[Yinghai Lu]

Now we can safely extend parent top and shrink them according iobusn_resource tree.

Don't need that any more.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
---
 drivers/pci/probe.c |   32 --------------------------------
 1 files changed, 0 insertions(+), 32 deletions(-)

diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index bff571b..1492ea2 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -608,22 +608,6 @@ struct pci_bus *__ref pci_add_new_bus(struct pci_bus *parent, struct pci_dev *de
 	return child;
 }
 
-static void pci_fixup_parent_subordinate_busnr(struct pci_bus *child, int max)
-{
-	struct pci_bus *parent = child->parent;
-
-	/* Attempts to fix that up are really dangerous unless
-	   we're going to re-assign all bus numbers. */
-	if (!pcibios_assign_all_busses())
-		return;
-
-	while (parent->parent && parent->subordinate < max) {
-		parent->subordinate = max;
-		pci_write_config_byte(parent->self, PCI_SUBORDINATE_BUS, max);
-		parent = parent->parent;
-	}
-}
-
 static void __devinit pci_bus_update_top(struct pci_bus *parent,
 		 long size, struct resource *parent_res)
 {
@@ -954,23 +938,7 @@ int __devinit pci_scan_bridge(struct pci_bus *bus, struct pci_dev *dev, int max,
 
 		if (!is_cardbus) {
 			child->bridge_ctl = bctl;
-			/*
-			 * Adjust subordinate busnr in parent buses.
-			 * We do this before scanning for children because
-			 * some devices may not be detected if the bios
-			 * was lazy.
-			 */
-			pci_fixup_parent_subordinate_busnr(child, max);
-			/* Now we can scan all subordinate buses... */
 			max = pci_scan_child_bus(child);
-			/*
-			 * now fix it up again since we have found
-			 * the real value of max.
-			 */
-			pci_fixup_parent_subordinate_busnr(child, max);
-
-		} else {
-			pci_fixup_parent_subordinate_busnr(child, max);
 		}
 		/*
 		 * Set the subordinate bus number to its real value.
-- 
1.7.7

[PATCH 13/22] PCI: kill pci_fixup_parent_subordinate_busnr()

[Yinghai Lu]

Now we can safely extend parent top and shrink them according iobusn_resource tree.

Don't need that any more.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
---
 drivers/pci/probe.c |   32 --------------------------------
 1 files changed, 0 insertions(+), 32 deletions(-)

diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index bff571b..1492ea2 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -608,22 +608,6 @@ struct pci_bus *__ref pci_add_new_bus(struct pci_bus *parent, struct pci_dev *de
 	return child;
 }
 
-static void pci_fixup_parent_subordinate_busnr(struct pci_bus *child, int max)
-{
-	struct pci_bus *parent = child->parent;
-
-	/* Attempts to fix that up are really dangerous unless
-	   we're going to re-assign all bus numbers. */
-	if (!pcibios_assign_all_busses())
-		return;
-
-	while (parent->parent && parent->subordinate < max) {
-		parent->subordinate = max;
-		pci_write_config_byte(parent->self, PCI_SUBORDINATE_BUS, max);
-		parent = parent->parent;
-	}
-}
-
 static void __devinit pci_bus_update_top(struct pci_bus *parent,
 		 long size, struct resource *parent_res)
 {
@@ -954,23 +938,7 @@ int __devinit pci_scan_bridge(struct pci_bus *bus, struct pci_dev *dev, int max,
 
 		if (!is_cardbus) {
 			child->bridge_ctl = bctl;
-			/*
-			 * Adjust subordinate busnr in parent buses.
-			 * We do this before scanning for children because
-			 * some devices may not be detected if the bios
-			 * was lazy.
-			 */
-			pci_fixup_parent_subordinate_busnr(child, max);
-			/* Now we can scan all subordinate buses... */
 			max = pci_scan_child_bus(child);
-			/*
-			 * now fix it up again since we have found
-			 * the real value of max.
-			 */
-			pci_fixup_parent_subordinate_busnr(child, max);
-
-		} else {
-			pci_fixup_parent_subordinate_busnr(child, max);
 		}
 		/*
 		 * Set the subordinate bus number to its real value.
-- 
1.7.7

[PATCH 14/22] PCI: Seperate child bus scanning to two passes overall

[Yinghai Lu]

In extreme case: Two bridges are properly setup.
       bridge A
               bridge AA
               bridge AB
       bridge B
	       bridge BA
	       bridge BB
   but AA, AB are not setup properly.
   bridge A has small range, and bridge AB could need more, when do the
       first pass0 for bridge A, it will do pass0 and pass1 for AA and AB,
	during that process, it will extend range of A for AB blindly.
	because bridge B is not registered yet.
       that could overlap range that is used by bridge B.

Right way should be:
       do pass0 for all good bridges at first.
So we could do pass0 for bridge B before pass1 for bridge AB.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
---
 drivers/pci/probe.c |   50 ++++++++++++++++++++++++++++++++++----------------
 1 files changed, 34 insertions(+), 16 deletions(-)

diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index 1492ea2..346dc22 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -778,6 +778,9 @@ static int __devinit pci_bridge_check_busn_broken(struct pci_bus *bus,
 
 	return broken;
 }
+
+static unsigned int __devinit __pci_scan_child_bus(struct pci_bus *bus,
+						 int pass);
 /*
  * If it's a bridge, configure it and scan the bus behind it.
  * For CardBus bridges, we don't scan behind as the devices will
@@ -829,11 +832,10 @@ int __devinit pci_scan_bridge(struct pci_bus *bus, struct pci_dev *dev, int max,
 	    !is_cardbus && !broken) {
 		unsigned int cmax;
 		/*
-		 * Bus already configured by firmware, process it in the first
-		 * pass and just note the configuration.
+		 * Bus already configured by firmware, still process it in two
+		 * passes in extreme case like two adjaced bridges have children
+		 * bridges that are not setup properly.
 		 */
-		if (pass)
-			goto out;
 
 		/*
 		 * If we already got to this bus through a different bridge,
@@ -854,7 +856,7 @@ int __devinit pci_scan_bridge(struct pci_bus *bus, struct pci_dev *dev, int max,
 			pci_bus_insert_busn_res(child, secondary, subordinate);
 		}
 
-		cmax = pci_scan_child_bus(child);
+		cmax = __pci_scan_child_bus(child, pass);
 		if (cmax > max)
 			max = cmax;
 		if (child->subordinate > max)
@@ -1649,12 +1651,13 @@ void pcie_bus_configure_settings(struct pci_bus *bus, u8 mpss)
 }
 EXPORT_SYMBOL_GPL(pcie_bus_configure_settings);
 
-unsigned int __devinit pci_scan_child_bus(struct pci_bus *bus)
+static unsigned int __devinit __pci_scan_child_bus(struct pci_bus *bus,
+						 int pass)
 {
-	unsigned int devfn, pass, max = bus->secondary;
+	unsigned int devfn, max = bus->secondary;
 	struct pci_dev *dev;
 
-	dev_dbg(&bus->dev, "scanning bus\n");
+	dev_dbg(&bus->dev, "scanning bus pass %d\n", pass);
 
 	/* Go find them, Rover! */
 	for (devfn = 0; devfn < 0x100; devfn += 8)
@@ -1668,18 +1671,16 @@ unsigned int __devinit pci_scan_child_bus(struct pci_bus *bus)
 	 * all PCI-to-PCI bridges on this bus.
 	 */
 	if (!bus->is_added) {
-		dev_dbg(&bus->dev, "fixups for bus\n");
+		dev_dbg(&bus->dev, "fixups for bus pass %d\n", pass);
 		pcibios_fixup_bus(bus);
 		if (pci_is_root_bus(bus))
 			bus->is_added = 1;
 	}
 
-	for (pass=0; pass < 2; pass++)
-		list_for_each_entry(dev, &bus->devices, bus_list) {
-			if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE ||
-			    dev->hdr_type == PCI_HEADER_TYPE_CARDBUS)
-				max = pci_scan_bridge(bus, dev, max, pass);
-		}
+	list_for_each_entry(dev, &bus->devices, bus_list)
+		if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE ||
+		    dev->hdr_type == PCI_HEADER_TYPE_CARDBUS)
+			max = pci_scan_bridge(bus, dev, max, pass);
 
 	/*
 	 * We've scanned the bus and so we know all about what's on
@@ -1688,7 +1689,24 @@ unsigned int __devinit pci_scan_child_bus(struct pci_bus *bus)
 	 *
 	 * Return how far we've got finding sub-buses.
 	 */
-	dev_dbg(&bus->dev, "bus scan returning with max=%02x\n", max);
+	dev_dbg(&bus->dev, "bus scan returning with max=%02x pass %d\n",
+			max, pass);
+
+	return max;
+}
+
+unsigned int __devinit pci_scan_child_bus(struct pci_bus *bus)
+{
+	int pass;
+	unsigned int max = 0, tmp;
+
+	for (pass = 0; pass < 2;  pass++) {
+		tmp = __pci_scan_child_bus(bus, pass);
+
+		if (tmp > max)
+			max = tmp;
+	}
+
 	return max;
 }
 
-- 
1.7.7

[PATCH 14/22] PCI: Seperate child bus scanning to two passes overall

[Yinghai Lu]

In extreme case: Two bridges are properly setup.
       bridge A
               bridge AA
               bridge AB
       bridge B
	       bridge BA
	       bridge BB
   but AA, AB are not setup properly.
   bridge A has small range, and bridge AB could need more, when do the
       first pass0 for bridge A, it will do pass0 and pass1 for AA and AB,
	during that process, it will extend range of A for AB blindly.
	because bridge B is not registered yet.
       that could overlap range that is used by bridge B.

Right way should be:
       do pass0 for all good bridges at first.
So we could do pass0 for bridge B before pass1 for bridge AB.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
---
 drivers/pci/probe.c |   50 ++++++++++++++++++++++++++++++++++----------------
 1 files changed, 34 insertions(+), 16 deletions(-)

diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index 1492ea2..346dc22 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -778,6 +778,9 @@ static int __devinit pci_bridge_check_busn_broken(struct pci_bus *bus,
 
 	return broken;
 }
+
+static unsigned int __devinit __pci_scan_child_bus(struct pci_bus *bus,
+						 int pass);
 /*
  * If it's a bridge, configure it and scan the bus behind it.
  * For CardBus bridges, we don't scan behind as the devices will
@@ -829,11 +832,10 @@ int __devinit pci_scan_bridge(struct pci_bus *bus, struct pci_dev *dev, int max,
 	    !is_cardbus && !broken) {
 		unsigned int cmax;
 		/*
-		 * Bus already configured by firmware, process it in the first
-		 * pass and just note the configuration.
+		 * Bus already configured by firmware, still process it in two
+		 * passes in extreme case like two adjaced bridges have children
+		 * bridges that are not setup properly.
 		 */
-		if (pass)
-			goto out;
 
 		/*
 		 * If we already got to this bus through a different bridge,
@@ -854,7 +856,7 @@ int __devinit pci_scan_bridge(struct pci_bus *bus, struct pci_dev *dev, int max,
 			pci_bus_insert_busn_res(child, secondary, subordinate);
 		}
 
-		cmax = pci_scan_child_bus(child);
+		cmax = __pci_scan_child_bus(child, pass);
 		if (cmax > max)
 			max = cmax;
 		if (child->subordinate > max)
@@ -1649,12 +1651,13 @@ void pcie_bus_configure_settings(struct pci_bus *bus, u8 mpss)
 }
 EXPORT_SYMBOL_GPL(pcie_bus_configure_settings);
 
-unsigned int __devinit pci_scan_child_bus(struct pci_bus *bus)
+static unsigned int __devinit __pci_scan_child_bus(struct pci_bus *bus,
+						 int pass)
 {
-	unsigned int devfn, pass, max = bus->secondary;
+	unsigned int devfn, max = bus->secondary;
 	struct pci_dev *dev;
 
-	dev_dbg(&bus->dev, "scanning bus\n");
+	dev_dbg(&bus->dev, "scanning bus pass %d\n", pass);
 
 	/* Go find them, Rover! */
 	for (devfn = 0; devfn < 0x100; devfn += 8)
@@ -1668,18 +1671,16 @@ unsigned int __devinit pci_scan_child_bus(struct pci_bus *bus)
 	 * all PCI-to-PCI bridges on this bus.
 	 */
 	if (!bus->is_added) {
-		dev_dbg(&bus->dev, "fixups for bus\n");
+		dev_dbg(&bus->dev, "fixups for bus pass %d\n", pass);
 		pcibios_fixup_bus(bus);
 		if (pci_is_root_bus(bus))
 			bus->is_added = 1;
 	}
 
-	for (pass=0; pass < 2; pass++)
-		list_for_each_entry(dev, &bus->devices, bus_list) {
-			if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE ||
-			    dev->hdr_type == PCI_HEADER_TYPE_CARDBUS)
-				max = pci_scan_bridge(bus, dev, max, pass);
-		}
+	list_for_each_entry(dev, &bus->devices, bus_list)
+		if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE ||
+		    dev->hdr_type == PCI_HEADER_TYPE_CARDBUS)
+			max = pci_scan_bridge(bus, dev, max, pass);
 
 	/*
 	 * We've scanned the bus and so we know all about what's on
@@ -1688,7 +1689,24 @@ unsigned int __devinit pci_scan_child_bus(struct pci_bus *bus)
 	 *
 	 * Return how far we've got finding sub-buses.
 	 */
-	dev_dbg(&bus->dev, "bus scan returning with max=%02x\n", max);
+	dev_dbg(&bus->dev, "bus scan returning with max=%02x pass %d\n",
+			max, pass);
+
+	return max;
+}
+
+unsigned int __devinit pci_scan_child_bus(struct pci_bus *bus)
+{
+	int pass;
+	unsigned int max = 0, tmp;
+
+	for (pass = 0; pass < 2;  pass++) {
+		tmp = __pci_scan_child_bus(bus, pass);
+
+		if (tmp > max)
+			max = tmp;
+	}
+
 	return max;
 }
 
-- 
1.7.7

[PATCH 15/22] pcmcia: remove workaround for fixing pci parent bus subordinate

[Yinghai Lu]

Now pci busn allocation code is there, and it will preallocate bus number and it
will make sure parent buses subordinate is right.

So remove workaround here.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Tested-by: Dominik Brodowski <linux@dominikbrodowski.net>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Mauro Carvalho Chehab <mchehab@redhat.com>
Cc: linux-pcmcia@lists.infradead.org
---
 drivers/pcmcia/yenta_socket.c |   75 -----------------------------------------
 1 files changed, 0 insertions(+), 75 deletions(-)

diff --git a/drivers/pcmcia/yenta_socket.c b/drivers/pcmcia/yenta_socket.c
index 849c0c1..5757cae 100644
--- a/drivers/pcmcia/yenta_socket.c
+++ b/drivers/pcmcia/yenta_socket.c
@@ -1064,79 +1064,6 @@ static void yenta_config_init(struct yenta_socket *socket)
 	config_writew(socket, CB_BRIDGE_CONTROL, bridge);
 }
 
-/**
- * yenta_fixup_parent_bridge - Fix subordinate bus# of the parent bridge
- * @cardbus_bridge: The PCI bus which the CardBus bridge bridges to
- *
- * Checks if devices on the bus which the CardBus bridge bridges to would be
- * invisible during PCI scans because of a misconfigured subordinate number
- * of the parent brige - some BIOSes seem to be too lazy to set it right.
- * Does the fixup carefully by checking how far it can go without conflicts.
- * See http://bugzilla.kernel.org/show_bug.cgi?id=2944 for more information.
- */
-static void yenta_fixup_parent_bridge(struct pci_bus *cardbus_bridge)
-{
-	struct list_head *tmp;
-	unsigned char upper_limit;
-	/*
-	 * We only check and fix the parent bridge: All systems which need
-	 * this fixup that have been reviewed are laptops and the only bridge
-	 * which needed fixing was the parent bridge of the CardBus bridge:
-	 */
-	struct pci_bus *bridge_to_fix = cardbus_bridge->parent;
-
-	/* Check bus numbers are already set up correctly: */
-	if (bridge_to_fix->subordinate >= cardbus_bridge->subordinate)
-		return; /* The subordinate number is ok, nothing to do */
-
-	if (!bridge_to_fix->parent)
-		return; /* Root bridges are ok */
-
-	/* stay within the limits of the bus range of the parent: */
-	upper_limit = bridge_to_fix->parent->subordinate;
-
-	/* check the bus ranges of all silbling bridges to prevent overlap */
-	list_for_each(tmp, &bridge_to_fix->parent->children) {
-		struct pci_bus *silbling = pci_bus_b(tmp);
-		/*
-		 * If the silbling has a higher secondary bus number
-		 * and it's secondary is equal or smaller than our
-		 * current upper limit, set the new upper limit to
-		 * the bus number below the silbling's range:
-		 */
-		if (silbling->secondary > bridge_to_fix->subordinate
-		    && silbling->secondary <= upper_limit)
-			upper_limit = silbling->secondary - 1;
-	}
-
-	/* Show that the wanted subordinate number is not possible: */
-	if (cardbus_bridge->subordinate > upper_limit)
-		dev_printk(KERN_WARNING, &cardbus_bridge->dev,
-			   "Upper limit for fixing this "
-			   "bridge's parent bridge: #%02x\n", upper_limit);
-
-	/* If we have room to increase the bridge's subordinate number, */
-	if (bridge_to_fix->subordinate < upper_limit) {
-
-		/* use the highest number of the hidden bus, within limits */
-		unsigned char subordinate_to_assign =
-			min(cardbus_bridge->subordinate, upper_limit);
-
-		dev_printk(KERN_INFO, &bridge_to_fix->dev,
-			   "Raising subordinate bus# of parent "
-			   "bus (#%02x) from #%02x to #%02x\n",
-			   bridge_to_fix->number,
-			   bridge_to_fix->subordinate, subordinate_to_assign);
-
-		/* Save the new subordinate in the bus struct of the bridge */
-		bridge_to_fix->subordinate = subordinate_to_assign;
-
-		/* and update the PCI config space with the new subordinate */
-		pci_write_config_byte(bridge_to_fix->self,
-			PCI_SUBORDINATE_BUS, bridge_to_fix->subordinate);
-	}
-}
-
 /*
  * Initialize a cardbus controller. Make sure we have a usable
  * interrupt, and that we can map the cardbus area. Fill in the
@@ -1257,8 +1184,6 @@ static int __devinit yenta_probe(struct pci_dev *dev, const struct pci_device_id
 	dev_printk(KERN_INFO, &dev->dev,
 		   "Socket status: %08x\n", cb_readl(socket, CB_SOCKET_STATE));
 
-	yenta_fixup_parent_bridge(dev->subordinate);
-
 	/* Register it with the pcmcia layer.. */
 	ret = pcmcia_register_socket(&socket->socket);
 	if (ret == 0) {
-- 
1.7.7

[PATCH 15/22] pcmcia: remove workaround for fixing pci parent bus subordinate

[Yinghai Lu]

Now pci busn allocation code is there, and it will preallocate bus number and it
will make sure parent buses subordinate is right.

So remove workaround here.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Tested-by: Dominik Brodowski <linux@dominikbrodowski.net>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Mauro Carvalho Chehab <mchehab@redhat.com>
Cc: linux-pcmcia@lists.infradead.org
---
 drivers/pcmcia/yenta_socket.c |   75 -----------------------------------------
 1 files changed, 0 insertions(+), 75 deletions(-)

diff --git a/drivers/pcmcia/yenta_socket.c b/drivers/pcmcia/yenta_socket.c
index 849c0c1..5757cae 100644
--- a/drivers/pcmcia/yenta_socket.c
+++ b/drivers/pcmcia/yenta_socket.c
@@ -1064,79 +1064,6 @@ static void yenta_config_init(struct yenta_socket *socket)
 	config_writew(socket, CB_BRIDGE_CONTROL, bridge);
 }
 
-/**
- * yenta_fixup_parent_bridge - Fix subordinate bus# of the parent bridge
- * @cardbus_bridge: The PCI bus which the CardBus bridge bridges to
- *
- * Checks if devices on the bus which the CardBus bridge bridges to would be
- * invisible during PCI scans because of a misconfigured subordinate number
- * of the parent brige - some BIOSes seem to be too lazy to set it right.
- * Does the fixup carefully by checking how far it can go without conflicts.
- * See http://bugzilla.kernel.org/show_bug.cgi?id=2944 for more information.
- */
-static void yenta_fixup_parent_bridge(struct pci_bus *cardbus_bridge)
-{
-	struct list_head *tmp;
-	unsigned char upper_limit;
-	/*
-	 * We only check and fix the parent bridge: All systems which need
-	 * this fixup that have been reviewed are laptops and the only bridge
-	 * which needed fixing was the parent bridge of the CardBus bridge:
-	 */
-	struct pci_bus *bridge_to_fix = cardbus_bridge->parent;
-
-	/* Check bus numbers are already set up correctly: */
-	if (bridge_to_fix->subordinate >= cardbus_bridge->subordinate)
-		return; /* The subordinate number is ok, nothing to do */
-
-	if (!bridge_to_fix->parent)
-		return; /* Root bridges are ok */
-
-	/* stay within the limits of the bus range of the parent: */
-	upper_limit = bridge_to_fix->parent->subordinate;
-
-	/* check the bus ranges of all silbling bridges to prevent overlap */
-	list_for_each(tmp, &bridge_to_fix->parent->children) {
-		struct pci_bus *silbling = pci_bus_b(tmp);
-		/*
-		 * If the silbling has a higher secondary bus number
-		 * and it's secondary is equal or smaller than our
-		 * current upper limit, set the new upper limit to
-		 * the bus number below the silbling's range:
-		 */
-		if (silbling->secondary > bridge_to_fix->subordinate
-		    && silbling->secondary <= upper_limit)
-			upper_limit = silbling->secondary - 1;
-	}
-
-	/* Show that the wanted subordinate number is not possible: */
-	if (cardbus_bridge->subordinate > upper_limit)
-		dev_printk(KERN_WARNING, &cardbus_bridge->dev,
-			   "Upper limit for fixing this "
-			   "bridge's parent bridge: #%02x\n", upper_limit);
-
-	/* If we have room to increase the bridge's subordinate number, */
-	if (bridge_to_fix->subordinate < upper_limit) {
-
-		/* use the highest number of the hidden bus, within limits */
-		unsigned char subordinate_to_assign =
-			min(cardbus_bridge->subordinate, upper_limit);
-
-		dev_printk(KERN_INFO, &bridge_to_fix->dev,
-			   "Raising subordinate bus# of parent "
-			   "bus (#%02x) from #%02x to #%02x\n",
-			   bridge_to_fix->number,
-			   bridge_to_fix->subordinate, subordinate_to_assign);
-
-		/* Save the new subordinate in the bus struct of the bridge */
-		bridge_to_fix->subordinate = subordinate_to_assign;
-
-		/* and update the PCI config space with the new subordinate */
-		pci_write_config_byte(bridge_to_fix->self,
-			PCI_SUBORDINATE_BUS, bridge_to_fix->subordinate);
-	}
-}
-
 /*
  * Initialize a cardbus controller. Make sure we have a usable
  * interrupt, and that we can map the cardbus area. Fill in the
@@ -1257,8 +1184,6 @@ static int __devinit yenta_probe(struct pci_dev *dev, const struct pci_device_id
 	dev_printk(KERN_INFO, &dev->dev,
 		   "Socket status: %08x\n", cb_readl(socket, CB_SOCKET_STATE));
 
-	yenta_fixup_parent_bridge(dev->subordinate);
-
 	/* Register it with the pcmcia layer.. */
 	ret = pcmcia_register_socket(&socket->socket);
 	if (ret == 0) {
-- 
1.7.7

[PATCH 16/22] PCI: Double checking setting for bus register and bus struct.

[Yinghai Lu]

User could use setpci change bridge's bus register. that could make value of register
and struct is out of sync.
User later will use rescan to see the devices is moving.

In the rescaning, we need to double check the range and remove the old struct at first.

to make thing working user may need have script to remove children devices under bridge
at first, and then use setpci update bus register and then rescan.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
---
 drivers/pci/probe.c |   40 ++++++++++++++++++++++++++++++++++++++++
 1 files changed, 40 insertions(+), 0 deletions(-)

diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index 346dc22..009946a 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -814,6 +814,46 @@ int __devinit pci_scan_bridge(struct pci_bus *bus, struct pci_dev *dev, int max,
 	    (primary != bus->number || secondary <= bus->number))
 		broken = 1;
 
+	if (!pass && dev->subordinate) {
+		child = dev->subordinate;
+		/*
+		 * User could change bus register in bridge manually with
+		 * setpci and rescan. So double check the setting, and remove
+		 * old structs.  Don't set broken yet, let following check
+		 * to see if the new setting good.
+		 */
+		if (primary != child->primary ||
+		    secondary != child->secondary ||
+		    subordinate != child->subordinate) {
+			dev_info(&dev->dev,
+				"someone changed bus register from pri:%02x, sec:%02x, sub:%02x to pri:%02x, sec:%02x, sub:%02x\n",
+				child->primary, child->secondary, child->subordinate,
+				primary, secondary, subordinate);
+			if (!list_empty(&dev->subordinate->devices)) {
+				u32 old_buses;
+
+				dev_info(&dev->dev,
+				 "but children devices are not removed manually before that.\n");
+				/*
+				 * Try best to remove left children devices
+				 * but we need to set bus register back, otherwise
+				 * We can not access children device and stop them
+				 */
+				old_buses = (buses & 0xff000000)
+				   | ((unsigned int)(child->primary)     <<  0)
+				   | ((unsigned int)(child->secondary)   <<  8)
+				   | ((unsigned int)(child->subordinate) << 16);
+				pci_write_config_dword(dev, PCI_PRIMARY_BUS,
+							 old_buses);
+				pci_remove_behind_bridge(dev);
+				pci_write_config_dword(dev, PCI_PRIMARY_BUS,
+							 buses);
+			}
+			pci_remove_bus(dev->subordinate);
+			dev->subordinate = NULL;
+		}
+	}
+
 	/* more strict checking */
 	if (!pass && !broken && !dev->subordinate)
 		broken = pci_bridge_check_busn_broken(bus, dev,
-- 
1.7.7

[PATCH 16/22] PCI: Double checking setting for bus register and bus struct.

[Yinghai Lu]

User could use setpci change bridge's bus register. that could make value of register
and struct is out of sync.
User later will use rescan to see the devices is moving.

In the rescaning, we need to double check the range and remove the old struct at first.

to make thing working user may need have script to remove children devices under bridge
at first, and then use setpci update bus register and then rescan.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
---
 drivers/pci/probe.c |   40 ++++++++++++++++++++++++++++++++++++++++
 1 files changed, 40 insertions(+), 0 deletions(-)

diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index 346dc22..009946a 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -814,6 +814,46 @@ int __devinit pci_scan_bridge(struct pci_bus *bus, struct pci_dev *dev, int max,
 	    (primary != bus->number || secondary <= bus->number))
 		broken = 1;
 
+	if (!pass && dev->subordinate) {
+		child = dev->subordinate;
+		/*
+		 * User could change bus register in bridge manually with
+		 * setpci and rescan. So double check the setting, and remove
+		 * old structs.  Don't set broken yet, let following check
+		 * to see if the new setting good.
+		 */
+		if (primary != child->primary ||
+		    secondary != child->secondary ||
+		    subordinate != child->subordinate) {
+			dev_info(&dev->dev,
+				"someone changed bus register from pri:%02x, sec:%02x, sub:%02x to pri:%02x, sec:%02x, sub:%02x\n",
+				child->primary, child->secondary, child->subordinate,
+				primary, secondary, subordinate);
+			if (!list_empty(&dev->subordinate->devices)) {
+				u32 old_buses;
+
+				dev_info(&dev->dev,
+				 "but children devices are not removed manually before that.\n");
+				/*
+				 * Try best to remove left children devices
+				 * but we need to set bus register back, otherwise
+				 * We can not access children device and stop them
+				 */
+				old_buses = (buses & 0xff000000)
+				   | ((unsigned int)(child->primary)     <<  0)
+				   | ((unsigned int)(child->secondary)   <<  8)
+				   | ((unsigned int)(child->subordinate) << 16);
+				pci_write_config_dword(dev, PCI_PRIMARY_BUS,
+							 old_buses);
+				pci_remove_behind_bridge(dev);
+				pci_write_config_dword(dev, PCI_PRIMARY_BUS,
+							 buses);
+			}
+			pci_remove_bus(dev->subordinate);
+			dev->subordinate = NULL;
+		}
+	}
+
 	/* more strict checking */
 	if (!pass && !broken && !dev->subordinate)
 		broken = pci_bridge_check_busn_broken(bus, dev,
-- 
1.7.7

[PATCH 17/22] PCI, pciehp: Remove not needed bus number range checking

[Yinghai Lu]

Found hotplug adding one EM with bridge fail, bios only leave one bus range
 for slot.

[ 1169.621444] pciehp: No bus number available for hot-added bridge 0000:55:00.0
[ 1169.633277] pcieport 0000:40:03.0: PCI bridge to [bus 55-55]

With busn_res tracking and allocating, we don't need that checking anymore.

Parent bridges' bus number will be extended safely.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
---
 drivers/pci/hotplug/pciehp_pci.c |   12 +-----------
 1 files changed, 1 insertions(+), 11 deletions(-)

diff --git a/drivers/pci/hotplug/pciehp_pci.c b/drivers/pci/hotplug/pciehp_pci.c
index a4031df..df1f3ed 100644
--- a/drivers/pci/hotplug/pciehp_pci.c
+++ b/drivers/pci/hotplug/pciehp_pci.c
@@ -37,18 +37,8 @@
 static int __ref pciehp_add_bridge(struct pci_dev *dev)
 {
 	struct pci_bus *parent = dev->bus;
-	int pass, busnr, start = parent->secondary;
-	int end = parent->subordinate;
+	int pass, busnr = parent->secondary;
 
-	for (busnr = start; busnr <= end; busnr++) {
-		if (!pci_find_bus(pci_domain_nr(parent), busnr))
-			break;
-	}
-	if (busnr-- > end) {
-		err("No bus number available for hot-added bridge %s\n",
-				pci_name(dev));
-		return -1;
-	}
 	for (pass = 0; pass < 2; pass++)
 		busnr = pci_scan_bridge(parent, dev, busnr, pass);
 	if (!dev->subordinate)
-- 
1.7.7

[PATCH 17/22] PCI, pciehp: Remove not needed bus number range checking

[Yinghai Lu]

Found hotplug adding one EM with bridge fail, bios only leave one bus range
 for slot.

[ 1169.621444] pciehp: No bus number available for hot-added bridge 0000:55:00.0
[ 1169.633277] pcieport 0000:40:03.0: PCI bridge to [bus 55-55]

With busn_res tracking and allocating, we don't need that checking anymore.

Parent bridges' bus number will be extended safely.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
---
 drivers/pci/hotplug/pciehp_pci.c |   12 +-----------
 1 files changed, 1 insertions(+), 11 deletions(-)

diff --git a/drivers/pci/hotplug/pciehp_pci.c b/drivers/pci/hotplug/pciehp_pci.c
index a4031df..df1f3ed 100644
--- a/drivers/pci/hotplug/pciehp_pci.c
+++ b/drivers/pci/hotplug/pciehp_pci.c
@@ -37,18 +37,8 @@
 static int __ref pciehp_add_bridge(struct pci_dev *dev)
 {
 	struct pci_bus *parent = dev->bus;
-	int pass, busnr, start = parent->secondary;
-	int end = parent->subordinate;
+	int pass, busnr = parent->secondary;
 
-	for (busnr = start; busnr <= end; busnr++) {
-		if (!pci_find_bus(pci_domain_nr(parent), busnr))
-			break;
-	}
-	if (busnr-- > end) {
-		err("No bus number available for hot-added bridge %s\n",
-				pci_name(dev));
-		return -1;
-	}
 	for (pass = 0; pass < 2; pass++)
 		busnr = pci_scan_bridge(parent, dev, busnr, pass);
 	if (!dev->subordinate)
-- 
1.7.7

[PATCH 18/22] PCI, sys: Use device_type and attr_groups with pci dev

[Yinghai Lu]

We want to create rescan in sys only for pci bridge instead of all pci dev.

We could use attribute_groups/is_visible method to do that.

Now pci dev does not use device type yet. So add pci_dev_type to take
attr_groups with it.

Add pci_dev_bridge_attrs_are_visible() to control attr_bridge_group only create
attr for bridge.

This is the framework related change, later could attr to bridge_attr_group,
to make those attr only show up on pci bridge device.

Also We could add more attr groups with is_visible to reduce messness in
	pci_create_sysfs_dev_files. ( at least for boot_vga one )

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
---
 drivers/pci/pci-sysfs.c |   30 ++++++++++++++++++++++++++++++
 drivers/pci/pci.h       |    1 +
 drivers/pci/probe.c     |    1 +
 3 files changed, 32 insertions(+), 0 deletions(-)

diff --git a/drivers/pci/pci-sysfs.c b/drivers/pci/pci-sysfs.c
index d972303..124e826 100644
--- a/drivers/pci/pci-sysfs.c
+++ b/drivers/pci/pci-sysfs.c
@@ -1335,3 +1335,33 @@ static int __init pci_sysfs_init(void)
 }
 
 late_initcall(pci_sysfs_init);
+
+static struct attribute *pci_dev_bridge_attrs[] = {
+	NULL,
+};
+
+static umode_t pci_dev_bridge_attrs_are_visible(struct kobject *kobj,
+						struct attribute *a, int n)
+{
+	struct device *dev = container_of(kobj, struct device, kobj);
+	struct pci_dev *pdev = to_pci_dev(dev);
+
+	if (!pdev->subordinate)
+		return 0;
+
+	return a->mode;
+}
+
+static struct attribute_group pci_dev_bridge_attr_group = {
+	.attrs = pci_dev_bridge_attrs,
+	.is_visible = pci_dev_bridge_attrs_are_visible,
+};
+
+static const struct attribute_group *pci_dev_attr_groups[] = {
+	&pci_dev_bridge_attr_group,
+	NULL,
+};
+
+struct device_type pci_dev_type = {
+	.groups = pci_dev_attr_groups,
+};
diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h
index f862a5a..8d17a1c 100644
--- a/drivers/pci/pci.h
+++ b/drivers/pci/pci.h
@@ -161,6 +161,7 @@ static inline int pci_no_d1d2(struct pci_dev *dev)
 }
 extern struct device_attribute pci_dev_attrs[];
 extern struct device_attribute pcibus_dev_attrs[];
+extern struct device_type pci_dev_type;
 #ifdef CONFIG_HOTPLUG
 extern struct bus_attribute pci_bus_attrs[];
 #else
diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index 009946a..b24fa1f 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -1100,6 +1100,7 @@ int pci_setup_device(struct pci_dev *dev)
 	dev->sysdata = dev->bus->sysdata;
 	dev->dev.parent = dev->bus->bridge;
 	dev->dev.bus = &pci_bus_type;
+	dev->dev.type = &pci_dev_type;
 	dev->hdr_type = hdr_type & 0x7f;
 	dev->multifunction = !!(hdr_type & 0x80);
 	dev->error_state = pci_channel_io_normal;
-- 
1.7.7

[PATCH 18/22] PCI, sys: Use device_type and attr_groups with pci dev

[Yinghai Lu]

We want to create rescan in sys only for pci bridge instead of all pci dev.

We could use attribute_groups/is_visible method to do that.

Now pci dev does not use device type yet. So add pci_dev_type to take
attr_groups with it.

Add pci_dev_bridge_attrs_are_visible() to control attr_bridge_group only create
attr for bridge.

This is the framework related change, later could attr to bridge_attr_group,
to make those attr only show up on pci bridge device.

Also We could add more attr groups with is_visible to reduce messness in
	pci_create_sysfs_dev_files. ( at least for boot_vga one )

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
---
 drivers/pci/pci-sysfs.c |   30 ++++++++++++++++++++++++++++++
 drivers/pci/pci.h       |    1 +
 drivers/pci/probe.c     |    1 +
 3 files changed, 32 insertions(+), 0 deletions(-)

diff --git a/drivers/pci/pci-sysfs.c b/drivers/pci/pci-sysfs.c
index d972303..124e826 100644
--- a/drivers/pci/pci-sysfs.c
+++ b/drivers/pci/pci-sysfs.c
@@ -1335,3 +1335,33 @@ static int __init pci_sysfs_init(void)
 }
 
 late_initcall(pci_sysfs_init);
+
+static struct attribute *pci_dev_bridge_attrs[] = {
+	NULL,
+};
+
+static umode_t pci_dev_bridge_attrs_are_visible(struct kobject *kobj,
+						struct attribute *a, int n)
+{
+	struct device *dev = container_of(kobj, struct device, kobj);
+	struct pci_dev *pdev = to_pci_dev(dev);
+
+	if (!pdev->subordinate)
+		return 0;
+
+	return a->mode;
+}
+
+static struct attribute_group pci_dev_bridge_attr_group = {
+	.attrs = pci_dev_bridge_attrs,
+	.is_visible = pci_dev_bridge_attrs_are_visible,
+};
+
+static const struct attribute_group *pci_dev_attr_groups[] = {
+	&pci_dev_bridge_attr_group,
+	NULL,
+};
+
+struct device_type pci_dev_type = {
+	.groups = pci_dev_attr_groups,
+};
diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h
index f862a5a..8d17a1c 100644
--- a/drivers/pci/pci.h
+++ b/drivers/pci/pci.h
@@ -161,6 +161,7 @@ static inline int pci_no_d1d2(struct pci_dev *dev)
 }
 extern struct device_attribute pci_dev_attrs[];
 extern struct device_attribute pcibus_dev_attrs[];
+extern struct device_type pci_dev_type;
 #ifdef CONFIG_HOTPLUG
 extern struct bus_attribute pci_bus_attrs[];
 #else
diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index 009946a..b24fa1f 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -1100,6 +1100,7 @@ int pci_setup_device(struct pci_dev *dev)
 	dev->sysdata = dev->bus->sysdata;
 	dev->dev.parent = dev->bus->bridge;
 	dev->dev.bus = &pci_bus_type;
+	dev->dev.type = &pci_dev_type;
 	dev->hdr_type = hdr_type & 0x7f;
 	dev->multifunction = !!(hdr_type & 0x80);
 	dev->error_state = pci_channel_io_normal;
-- 
1.7.7

[PATCH 19/22] PCI, sysfs: create rescan_bridge under /sys/.../pci/devices/... for pci bridges

[Yinghai Lu]

Current code will create rescan for every pci device under parent bus.
that is not right. the device is already there, there is no reason to rescan it.

We could have rescan for pci bridges. less confusing.

Need to move rescan attr to pci dev bridge attribute group.
And We should rescan bridge's secondary bus instead of primary bus.

-v3: Use device_type for pci dev.
-v4: Seperate pci device type change out
-v5: add rescan_bridge for bridge type, and still keep the old rescan.
	may remove the old rescan later.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
---
 Documentation/ABI/testing/sysfs-bus-pci |   10 ++++++++++
 drivers/pci/pci-sysfs.c                 |   24 ++++++++++++++++++++++++
 2 files changed, 34 insertions(+), 0 deletions(-)

diff --git a/Documentation/ABI/testing/sysfs-bus-pci b/Documentation/ABI/testing/sysfs-bus-pci
index 34f5110..95f0f37 100644
--- a/Documentation/ABI/testing/sysfs-bus-pci
+++ b/Documentation/ABI/testing/sysfs-bus-pci
@@ -111,6 +111,16 @@ Description:
 		from this part of the device tree.
 		Depends on CONFIG_HOTPLUG.
 
+What:		/sys/bus/pci/devices/.../rescan_bridge
+Date:		February 2012
+Contact:	Linux PCI developers <linux-pci@vger.kernel.org>
+Description:
+		Writing a non-zero value to this attribute will
+		force a rescan of the bridge and all child buses, and
+		re-discover devices removed earlier from this part of
+		the device tree.
+		Depends on CONFIG_HOTPLUG.
+
 What:		/sys/bus/pci/devices/.../reset
 Date:		July 2009
 Contact:	Michael S. Tsirkin <mst@redhat.com>
diff --git a/drivers/pci/pci-sysfs.c b/drivers/pci/pci-sysfs.c
index 124e826..68caf29 100644
--- a/drivers/pci/pci-sysfs.c
+++ b/drivers/pci/pci-sysfs.c
@@ -325,6 +325,27 @@ dev_rescan_store(struct device *dev, struct device_attribute *attr,
 	return count;
 }
 
+static ssize_t
+dev_bridge_rescan_store(struct device *dev, struct device_attribute *attr,
+		 const char *buf, size_t count)
+{
+	unsigned long val;
+	struct pci_dev *pdev = to_pci_dev(dev);
+
+	if (kstrtoul(buf, 0, &val) < 0)
+		return -EINVAL;
+
+	if (val) {
+		mutex_lock(&pci_remove_rescan_mutex);
+		pci_rescan_bus(pdev->subordinate);
+		mutex_unlock(&pci_remove_rescan_mutex);
+	}
+	return count;
+}
+
+static struct device_attribute pci_dev_bridge_rescan_attr =
+	__ATTR(rescan_bridge, (S_IWUSR|S_IWGRP), NULL, dev_bridge_rescan_store);
+
 static void remove_callback(struct device *dev)
 {
 	struct pci_dev *pdev = to_pci_dev(dev);
@@ -1337,6 +1358,9 @@ static int __init pci_sysfs_init(void)
 late_initcall(pci_sysfs_init);
 
 static struct attribute *pci_dev_bridge_attrs[] = {
+#ifdef CONFIG_HOTPLUG
+	&pci_dev_bridge_rescan_attr.attr,
+#endif
 	NULL,
 };
 
-- 
1.7.7

[PATCH 19/22] PCI, sysfs: create rescan_bridge under /sys/.../pci/devices/... for pci bridges

[Yinghai Lu]

Current code will create rescan for every pci device under parent bus.
that is not right. the device is already there, there is no reason to rescan it.

We could have rescan for pci bridges. less confusing.

Need to move rescan attr to pci dev bridge attribute group.
And We should rescan bridge's secondary bus instead of primary bus.

-v3: Use device_type for pci dev.
-v4: Seperate pci device type change out
-v5: add rescan_bridge for bridge type, and still keep the old rescan.
	may remove the old rescan later.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
---
 Documentation/ABI/testing/sysfs-bus-pci |   10 ++++++++++
 drivers/pci/pci-sysfs.c                 |   24 ++++++++++++++++++++++++
 2 files changed, 34 insertions(+), 0 deletions(-)

diff --git a/Documentation/ABI/testing/sysfs-bus-pci b/Documentation/ABI/testing/sysfs-bus-pci
index 34f5110..95f0f37 100644
--- a/Documentation/ABI/testing/sysfs-bus-pci
+++ b/Documentation/ABI/testing/sysfs-bus-pci
@@ -111,6 +111,16 @@ Description:
 		from this part of the device tree.
 		Depends on CONFIG_HOTPLUG.
 
+What:		/sys/bus/pci/devices/.../rescan_bridge
+Date:		February 2012
+Contact:	Linux PCI developers <linux-pci@vger.kernel.org>
+Description:
+		Writing a non-zero value to this attribute will
+		force a rescan of the bridge and all child buses, and
+		re-discover devices removed earlier from this part of
+		the device tree.
+		Depends on CONFIG_HOTPLUG.
+
 What:		/sys/bus/pci/devices/.../reset
 Date:		July 2009
 Contact:	Michael S. Tsirkin <mst@redhat.com>
diff --git a/drivers/pci/pci-sysfs.c b/drivers/pci/pci-sysfs.c
index 124e826..68caf29 100644
--- a/drivers/pci/pci-sysfs.c
+++ b/drivers/pci/pci-sysfs.c
@@ -325,6 +325,27 @@ dev_rescan_store(struct device *dev, struct device_attribute *attr,
 	return count;
 }
 
+static ssize_t
+dev_bridge_rescan_store(struct device *dev, struct device_attribute *attr,
+		 const char *buf, size_t count)
+{
+	unsigned long val;
+	struct pci_dev *pdev = to_pci_dev(dev);
+
+	if (kstrtoul(buf, 0, &val) < 0)
+		return -EINVAL;
+
+	if (val) {
+		mutex_lock(&pci_remove_rescan_mutex);
+		pci_rescan_bus(pdev->subordinate);
+		mutex_unlock(&pci_remove_rescan_mutex);
+	}
+	return count;
+}
+
+static struct device_attribute pci_dev_bridge_rescan_attr =
+	__ATTR(rescan_bridge, (S_IWUSR|S_IWGRP), NULL, dev_bridge_rescan_store);
+
 static void remove_callback(struct device *dev)
 {
 	struct pci_dev *pdev = to_pci_dev(dev);
@@ -1337,6 +1358,9 @@ static int __init pci_sysfs_init(void)
 late_initcall(pci_sysfs_init);
 
 static struct attribute *pci_dev_bridge_attrs[] = {
+#ifdef CONFIG_HOTPLUG
+	&pci_dev_bridge_rescan_attr.attr,
+#endif
 	NULL,
 };
 
-- 
1.7.7

[PATCH 20/22] PCI: Add pci_bus_add_single_device()

[Yinghai Lu]

will use it to pci_bus_bridge_scan_resize(0 to make bridge will
have pci_bus directory created.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
---
 drivers/pci/bus.c   |   40 ++++++++++++++++++++++++++++++++++++++++
 include/linux/pci.h |    1 +
 2 files changed, 41 insertions(+), 0 deletions(-)

diff --git a/drivers/pci/bus.c b/drivers/pci/bus.c
index 398f5d8..7b2ae85 100644
--- a/drivers/pci/bus.c
+++ b/drivers/pci/bus.c
@@ -247,6 +247,46 @@ void pci_bus_add_devices(const struct pci_bus *bus)
 	}
 }
 
+void pci_bus_add_single_device(struct pci_dev *dev)
+{
+	struct pci_bus *child;
+	int retval;
+
+	/* Skip already-added devices */
+	if (!dev->is_added) {
+		retval = pci_bus_add_device(dev);
+		if (retval)
+			dev_err(&dev->dev, "Error adding device, continuing\n");
+	}
+
+	BUG_ON(!dev->is_added);
+
+	child = dev->subordinate;
+	/*
+	 * If there is an unattached subordinate bus, attach
+	 * it and then scan for unattached PCI devices.
+	 */
+	if (child) {
+		if (list_empty(&child->node)) {
+			down_write(&pci_bus_sem);
+			list_add_tail(&child->node, &dev->bus->children);
+			up_write(&pci_bus_sem);
+		}
+		pci_bus_add_devices(child);
+
+		/*
+		 * register the bus with sysfs as the parent is now
+		 * properly registered.
+		 */
+		if (!child->is_added) {
+			retval = pci_bus_add_child(child);
+			if (retval)
+				dev_err(&dev->dev, "Error adding bus, continuing\n");
+		}
+	}
+}
+
+
 void pci_enable_bridges(struct pci_bus *bus)
 {
 	struct pci_dev *dev;
diff --git a/include/linux/pci.h b/include/linux/pci.h
index d5b6786..8061031 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -659,6 +659,7 @@ void pci_fixup_cardbus(struct pci_bus *);
 void pcibios_scan_specific_bus(int busn);
 extern struct pci_bus *pci_find_bus(int domain, int busnr);
 void pci_bus_add_devices(const struct pci_bus *bus);
+void pci_bus_add_single_device(struct pci_dev *dev);
 struct pci_bus *pci_scan_bus_parented(struct device *parent, int bus,
 				      struct pci_ops *ops, void *sysdata);
 struct pci_bus *pci_scan_bus(int bus, struct pci_ops *ops, void *sysdata);
-- 
1.7.7

[PATCH 20/22] PCI: Add pci_bus_add_single_device()

[Yinghai Lu]

will use it to pci_bus_bridge_scan_resize(0 to make bridge will
have pci_bus directory created.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
---
 drivers/pci/bus.c   |   40 ++++++++++++++++++++++++++++++++++++++++
 include/linux/pci.h |    1 +
 2 files changed, 41 insertions(+), 0 deletions(-)

diff --git a/drivers/pci/bus.c b/drivers/pci/bus.c
index 398f5d8..7b2ae85 100644
--- a/drivers/pci/bus.c
+++ b/drivers/pci/bus.c
@@ -247,6 +247,46 @@ void pci_bus_add_devices(const struct pci_bus *bus)
 	}
 }
 
+void pci_bus_add_single_device(struct pci_dev *dev)
+{
+	struct pci_bus *child;
+	int retval;
+
+	/* Skip already-added devices */
+	if (!dev->is_added) {
+		retval = pci_bus_add_device(dev);
+		if (retval)
+			dev_err(&dev->dev, "Error adding device, continuing\n");
+	}
+
+	BUG_ON(!dev->is_added);
+
+	child = dev->subordinate;
+	/*
+	 * If there is an unattached subordinate bus, attach
+	 * it and then scan for unattached PCI devices.
+	 */
+	if (child) {
+		if (list_empty(&child->node)) {
+			down_write(&pci_bus_sem);
+			list_add_tail(&child->node, &dev->bus->children);
+			up_write(&pci_bus_sem);
+		}
+		pci_bus_add_devices(child);
+
+		/*
+		 * register the bus with sysfs as the parent is now
+		 * properly registered.
+		 */
+		if (!child->is_added) {
+			retval = pci_bus_add_child(child);
+			if (retval)
+				dev_err(&dev->dev, "Error adding bus, continuing\n");
+		}
+	}
+}
+
+
 void pci_enable_bridges(struct pci_bus *bus)
 {
 	struct pci_dev *dev;
diff --git a/include/linux/pci.h b/include/linux/pci.h
index d5b6786..8061031 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -659,6 +659,7 @@ void pci_fixup_cardbus(struct pci_bus *);
 void pcibios_scan_specific_bus(int busn);
 extern struct pci_bus *pci_find_bus(int domain, int busnr);
 void pci_bus_add_devices(const struct pci_bus *bus);
+void pci_bus_add_single_device(struct pci_dev *dev);
 struct pci_bus *pci_scan_bus_parented(struct device *parent, int bus,
 				      struct pci_ops *ops, void *sysdata);
 struct pci_bus *pci_scan_bus(int bus, struct pci_ops *ops, void *sysdata);
-- 
1.7.7

[PATCH 21/22] PCI: make pci_rescan_bus_bridge_resize use pci_scan_bridge instead

[Yinghai Lu]

So after remove all children and then using setpci change bus register and rescan
bridge could use new set bus number.

Otherwise need to rescan parent bus, it would have too much overhead.

also need to use pci_bus_add_single_device to make sure new change bus have directory
 /sys/../.../pci_bus.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
---
 drivers/pci/probe.c |   10 ++++++----
 1 files changed, 6 insertions(+), 4 deletions(-)

diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index b24fa1f..54aeae0 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -1972,14 +1972,16 @@ EXPORT_SYMBOL(pci_scan_bus);
  */
 unsigned int __ref pci_rescan_bus_bridge_resize(struct pci_dev *bridge)
 {
-	unsigned int max;
-	struct pci_bus *bus = bridge->subordinate;
+	unsigned int max = 0;
+	int pass;
+	struct pci_bus *bus = bridge->bus;
 
-	max = pci_scan_child_bus(bus);
+	for (pass = 0; pass < 2; pass++)
+		max = pci_scan_bridge(bus, bridge, max, pass);
 
 	pci_assign_unassigned_bridge_resources(bridge);
 
-	pci_bus_add_devices(bus);
+	pci_bus_add_single_device(bridge);
 
 	return max;
 }
-- 
1.7.7

[PATCH 21/22] PCI: make pci_rescan_bus_bridge_resize use pci_scan_bridge instead

[Yinghai Lu]

So after remove all children and then using setpci change bus register and rescan
bridge could use new set bus number.

Otherwise need to rescan parent bus, it would have too much overhead.

also need to use pci_bus_add_single_device to make sure new change bus have directory
 /sys/../.../pci_bus.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
---
 drivers/pci/probe.c |   10 ++++++----
 1 files changed, 6 insertions(+), 4 deletions(-)

diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index b24fa1f..54aeae0 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -1972,14 +1972,16 @@ EXPORT_SYMBOL(pci_scan_bus);
  */
 unsigned int __ref pci_rescan_bus_bridge_resize(struct pci_dev *bridge)
 {
-	unsigned int max;
-	struct pci_bus *bus = bridge->subordinate;
+	unsigned int max = 0;
+	int pass;
+	struct pci_bus *bus = bridge->bus;
 
-	max = pci_scan_child_bus(bus);
+	for (pass = 0; pass < 2; pass++)
+		max = pci_scan_bridge(bus, bridge, max, pass);
 
 	pci_assign_unassigned_bridge_resources(bridge);
 
-	pci_bus_add_devices(bus);
+	pci_bus_add_single_device(bridge);
 
 	return max;
 }
-- 
1.7.7

[PATCH 22/22] PCI: clean up rescan_bus_bridge_resize

[Yinghai Lu]

Should only use it with bridge instead of bus.
it could get new subordinate. so can not use it with reguar bus.

in that case, use may need to make all children devices get removed already.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
---
 drivers/pci/pci-sysfs.c |    7 ++-----
 1 files changed, 2 insertions(+), 5 deletions(-)

diff --git a/drivers/pci/pci-sysfs.c b/drivers/pci/pci-sysfs.c
index 68caf29..a3fa64e 100644
--- a/drivers/pci/pci-sysfs.c
+++ b/drivers/pci/pci-sysfs.c
@@ -337,7 +337,7 @@ dev_bridge_rescan_store(struct device *dev, struct device_attribute *attr,
 
 	if (val) {
 		mutex_lock(&pci_remove_rescan_mutex);
-		pci_rescan_bus(pdev->subordinate);
+		pci_rescan_bus_bridge_resize(pdev);
 		mutex_unlock(&pci_remove_rescan_mutex);
 	}
 	return count;
@@ -387,10 +387,7 @@ dev_bus_rescan_store(struct device *dev, struct device_attribute *attr,
 
 	if (val) {
 		mutex_lock(&pci_remove_rescan_mutex);
-		if (!pci_is_root_bus(bus) && list_empty(&bus->devices))
-			pci_rescan_bus_bridge_resize(bus->self);
-		else
-			pci_rescan_bus(bus);
+		pci_rescan_bus(bus);
 		mutex_unlock(&pci_remove_rescan_mutex);
 	}
 	return count;
-- 
1.7.7