pci_bus_distribute_available_resources() and
pci_bridge_distribute_available_resources() retain bridge window resources
and related data needed for distributing the available window in
independent variables for io, memory, and prefetchable memory windows. The
code is essentially the same for all of them and therefore repeated three
times with different variable names.
Refactor pci_bus_distribute_available_resources() to take an array. This
is complicated slightly by the function taking advantage of passing the
struct as value, which cannot be done for arrays in C. Therefore, copy the
data into a local array in the stack in the first loop.
Variable names are (hopefully) improved slightly as well.
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
---
drivers/pci/setup-bus.c | 162 ++++++++++++++++++----------------------
include/linux/pci.h | 3 +-
2 files changed, 74 insertions(+), 91 deletions(-)
diff --git a/drivers/pci/setup-bus.c b/drivers/pci/setup-bus.c
index 720159bca54d..3bc329b1b923 100644
--- a/drivers/pci/setup-bus.c
+++ b/drivers/pci/setup-bus.c
@@ -2059,15 +2059,16 @@ static void remove_dev_resource(struct resource *avail, struct pci_dev *dev,
avail->start = min(avail->start + tmp, avail->end + 1);
}
-static void remove_dev_resources(struct pci_dev *dev, struct resource *io,
- struct resource *mmio,
- struct resource *mmio_pref)
+static void remove_dev_resources(struct pci_dev *dev,
+ struct resource available[PCI_P2P_BRIDGE_RESOURCE_NUM])
{
+ struct resource *mmio_pref = &available[PCI_BUS_BRIDGE_PREF_MEM_WINDOW];
struct resource *res;
pci_dev_for_each_resource(dev, res) {
if (resource_type(res) == IORESOURCE_IO) {
- remove_dev_resource(io, dev, res);
+ remove_dev_resource(&available[PCI_BUS_BRIDGE_IO_WINDOW],
+ dev, res);
} else if (resource_type(res) == IORESOURCE_MEM) {
/*
@@ -2081,10 +2082,13 @@ static void remove_dev_resources(struct pci_dev *dev, struct resource *io,
*/
if ((res->flags & IORESOURCE_PREFETCH) &&
((res->flags & IORESOURCE_MEM_64) ==
- (mmio_pref->flags & IORESOURCE_MEM_64)))
- remove_dev_resource(mmio_pref, dev, res);
- else
- remove_dev_resource(mmio, dev, res);
+ (mmio_pref->flags & IORESOURCE_MEM_64))) {
+ remove_dev_resource(&available[PCI_BUS_BRIDGE_PREF_MEM_WINDOW],
+ dev, res);
+ } else {
+ remove_dev_resource(&available[PCI_BUS_BRIDGE_MEM_WINDOW],
+ dev, res);
+ }
}
}
}
@@ -2099,45 +2103,39 @@ static void remove_dev_resources(struct pci_dev *dev, struct resource *io,
* shared with the bridges.
*/
static void pci_bus_distribute_available_resources(struct pci_bus *bus,
- struct list_head *add_list,
- struct resource io,
- struct resource mmio,
- struct resource mmio_pref)
+ struct list_head *add_list,
+ struct resource available_in[PCI_P2P_BRIDGE_RESOURCE_NUM])
{
+ struct resource available[PCI_P2P_BRIDGE_RESOURCE_NUM];
unsigned int normal_bridges = 0, hotplug_bridges = 0;
- struct resource *io_res, *mmio_res, *mmio_pref_res;
struct pci_dev *dev, *bridge = bus->self;
- resource_size_t io_per_b, mmio_per_b, mmio_pref_per_b, align;
+ resource_size_t per_bridge[PCI_P2P_BRIDGE_RESOURCE_NUM];
+ resource_size_t align;
+ int i;
- io_res = &bridge->resource[PCI_BRIDGE_IO_WINDOW];
- mmio_res = &bridge->resource[PCI_BRIDGE_MEM_WINDOW];
- mmio_pref_res = &bridge->resource[PCI_BRIDGE_PREF_MEM_WINDOW];
+ for (i = 0; i < PCI_P2P_BRIDGE_RESOURCE_NUM; i++) {
+ struct resource *res = pci_bus_resource_n(bus, i);
- /*
- * The alignment of this bridge is yet to be considered, hence it must
- * be done now before extending its bridge window.
- */
- align = pci_resource_alignment(bridge, io_res);
- if (!io_res->parent && align)
- io.start = min(ALIGN(io.start, align), io.end + 1);
-
- align = pci_resource_alignment(bridge, mmio_res);
- if (!mmio_res->parent && align)
- mmio.start = min(ALIGN(mmio.start, align), mmio.end + 1);
+ available[i] = available_in[i];
- align = pci_resource_alignment(bridge, mmio_pref_res);
- if (!mmio_pref_res->parent && align)
- mmio_pref.start = min(ALIGN(mmio_pref.start, align),
- mmio_pref.end + 1);
+ /*
+ * The alignment of this bridge is yet to be considered,
+ * hence it must be done now before extending its bridge
+ * window.
+ */
+ align = pci_resource_alignment(bridge, res);
+ if (!res->parent && align)
+ available[i].start = min(ALIGN(available[i].start, align),
+ available[i].end + 1);
- /*
- * Now that we have adjusted for alignment, update the bridge window
- * resources to fill as much remaining resource space as possible.
- */
- adjust_bridge_window(bridge, io_res, add_list, resource_size(&io));
- adjust_bridge_window(bridge, mmio_res, add_list, resource_size(&mmio));
- adjust_bridge_window(bridge, mmio_pref_res, add_list,
- resource_size(&mmio_pref));
+ /*
+ * Now that we have adjusted for alignment, update the
+ * bridge window resources to fill as much remaining
+ * resource space as possible.
+ */
+ adjust_bridge_window(bridge, res, add_list,
+ resource_size(&available[i]));
+ }
/*
* Calculate how many hotplug bridges and normal bridges there
@@ -2161,7 +2159,7 @@ static void pci_bus_distribute_available_resources(struct pci_bus *bus,
*/
list_for_each_entry(dev, &bus->devices, bus_list) {
if (!dev->is_virtfn)
- remove_dev_resources(dev, &io, &mmio, &mmio_pref);
+ remove_dev_resources(dev, available);
}
/*
@@ -2173,16 +2171,9 @@ static void pci_bus_distribute_available_resources(struct pci_bus *bus,
* split between non-hotplug bridges. This is to allow possible
* hotplug bridges below them to get the extra space as well.
*/
- if (hotplug_bridges) {
- io_per_b = div64_ul(resource_size(&io), hotplug_bridges);
- mmio_per_b = div64_ul(resource_size(&mmio), hotplug_bridges);
- mmio_pref_per_b = div64_ul(resource_size(&mmio_pref),
- hotplug_bridges);
- } else {
- io_per_b = div64_ul(resource_size(&io), normal_bridges);
- mmio_per_b = div64_ul(resource_size(&mmio), normal_bridges);
- mmio_pref_per_b = div64_ul(resource_size(&mmio_pref),
- normal_bridges);
+ for (i = 0; i < PCI_P2P_BRIDGE_RESOURCE_NUM; i++) {
+ per_bridge[i] = div64_ul(resource_size(&available[i]),
+ hotplug_bridges ?: normal_bridges);
}
for_each_pci_bridge(dev, bus) {
@@ -2195,49 +2186,41 @@ static void pci_bus_distribute_available_resources(struct pci_bus *bus,
if (hotplug_bridges && !dev->is_hotplug_bridge)
continue;
- res = &dev->resource[PCI_BRIDGE_IO_WINDOW];
+ for (i = 0; i < PCI_P2P_BRIDGE_RESOURCE_NUM; i++) {
+ res = pci_bus_resource_n(bus, i);
- /*
- * Make sure the split resource space is properly aligned
- * for bridge windows (align it down to avoid going above
- * what is available).
- */
- align = pci_resource_alignment(dev, res);
- resource_set_size(&io, ALIGN_DOWN_IF_NONZERO(io_per_b, align));
-
- /*
- * The x_per_b holds the extra resource space that can be
- * added for each bridge but there is the minimal already
- * reserved as well so adjust x.start down accordingly to
- * cover the whole space.
- */
- io.start -= resource_size(res);
-
- res = &dev->resource[PCI_BRIDGE_MEM_WINDOW];
- align = pci_resource_alignment(dev, res);
- resource_set_size(&mmio,
- ALIGN_DOWN_IF_NONZERO(mmio_per_b,align));
- mmio.start -= resource_size(res);
+ /*
+ * Make sure the split resource space is properly
+ * aligned for bridge windows (align it down to
+ * avoid going above what is available).
+ */
+ align = pci_resource_alignment(dev, res);
+ resource_set_size(&available[i],
+ ALIGN_DOWN_IF_NONZERO(per_bridge[i],
+ align));
- res = &dev->resource[PCI_BRIDGE_PREF_MEM_WINDOW];
- align = pci_resource_alignment(dev, res);
- resource_set_size(&mmio_pref,
- ALIGN_DOWN_IF_NONZERO(mmio_pref_per_b, align));
- mmio_pref.start -= resource_size(res);
+ /*
+ * The per_bridge holds the extra resource space
+ * that can be added for each bridge but there is
+ * the minimal already reserved as well so adjust
+ * x.start down accordingly to cover the whole
+ * space.
+ */
+ available[i].start -= resource_size(res);
+ }
- pci_bus_distribute_available_resources(b, add_list, io, mmio,
- mmio_pref);
+ pci_bus_distribute_available_resources(b, add_list, available);
- io.start += io.end + 1;
- mmio.start += mmio.end + 1;
- mmio_pref.start += mmio_pref.end + 1;
+ for (i = 0; i < PCI_P2P_BRIDGE_RESOURCE_NUM; i++)
+ available[i].start += available[i].end + 1;
}
}
static void pci_bridge_distribute_available_resources(struct pci_dev *bridge,
struct list_head *add_list)
{
- struct resource available_io, available_mmio, available_mmio_pref;
+ struct resource *res, available[PCI_P2P_BRIDGE_RESOURCE_NUM];
+ unsigned int i;
if (!bridge->is_hotplug_bridge)
return;
@@ -2245,14 +2228,13 @@ static void pci_bridge_distribute_available_resources(struct pci_dev *bridge,
pci_dbg(bridge, "distributing available resources\n");
/* Take the initial extra resources from the hotplug port */
- available_io = bridge->resource[PCI_BRIDGE_IO_WINDOW];
- available_mmio = bridge->resource[PCI_BRIDGE_MEM_WINDOW];
- available_mmio_pref = bridge->resource[PCI_BRIDGE_PREF_MEM_WINDOW];
+ for (i = 0; i < PCI_P2P_BRIDGE_RESOURCE_NUM; i++) {
+ res = pci_resource_n(bridge, PCI_BRIDGE_RESOURCES + i);
+ available[i] = *res;
+ }
pci_bus_distribute_available_resources(bridge->subordinate,
- add_list, available_io,
- available_mmio,
- available_mmio_pref);
+ add_list, available);
}
static bool pci_bridge_resources_not_assigned(struct pci_dev *dev)
diff --git a/include/linux/pci.h b/include/linux/pci.h
index 275df4058767..723e9cede69d 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -119,7 +119,8 @@ enum {
#define PCI_CB_BRIDGE_MEM_1_WINDOW (PCI_BRIDGE_RESOURCES + 3)
/* Total number of bridge resources for P2P and CardBus */
-#define PCI_BRIDGE_RESOURCE_NUM 4
+#define PCI_P2P_BRIDGE_RESOURCE_NUM 3
+#define PCI_BRIDGE_RESOURCE_NUM 4
/* Resources assigned to buses behind the bridge */
PCI_BRIDGE_RESOURCES,
--
2.39.5
Hi Ilpo Järvinen,
This patch makes Thunderbolt unusable on my AMD Strix Halo platform.
Here's the dmesg output:
[ 4.212389] ------------[ cut here ]------------
[ 4.212391] WARNING: CPU: 6 PID: 272 at drivers/pci/pci.h:471 pci_bus_distribute_available_resources+0x6ad/0x6d0
[ 4.212400] Modules linked in: raid6_pq(+) hid_generic uas usb_storage scsi_mod usbhid hid scsi_common amdgpu amdxcp drm_panel_backlight_quirks gpu_sched drm_buddy drm_ttm_helper ttm drm_exec i2c_algo_bit drm_suballoc_helper drm_display_helper cec rc_core drm_client_lib drm_kms_helper sdhci_pci sdhci_uhs2 xhci_pci sp5100_tco xhci_hcd r8169 drm nvme sdhci watchdog realtek usbcore thunderbolt cqhci atlantic nvme_core mdio_devres psmouse libphy mmc_core nvme_keyring video i2c_piix4 macsec nvme_auth serio_raw mdio_bus i2c_smbus usb_common crc16 hkdf wmi
[ 4.212443] CPU: 6 UID: 0 PID: 272 Comm: irq/33-pciehp Not tainted 6.17.0+ #1 PREEMPT(voluntary)
[ 4.212447] Hardware name: PELADN YO Series/YO1, BIOS 1.04 05/15/2025
[ 4.212449] RIP: 0010:pci_bus_distribute_available_resources+0x6ad/0x6d0
[ 4.212453] Code: ff e9 a2 48 c7 c7 b8 b7 83 a3 4c 89 4c 24 18 e8 a9 2a fb ff 4c 8b 4c 24 18 e9 ca fd ff ff 48 8b 05 60 53 47 01 e9 94 fe ff ff <0f> 0b e9 5d fe ff ff 48 8b 05 55 53 47 01 e9 81 fe ff ff e8 4b 87
[ 4.212455] RSP: 0018:ffffaffcc0d4f9a8 EFLAGS: 00010206
[ 4.212458] RAX: 00000000000000cd RBX: ffff9721a687f800 RCX: ffff9721a687c828
[ 4.212459] RDX: 0000000000000000 RSI: 00000000000000cd RDI: ffff97218bc8a3c0
[ 4.212461] RBP: ffff9721a687c828 R08: ffffaffcc0d4f9f8 R09: 0000000000000001
[ 4.212462] R10: ffff97218bc8d700 R11: 0000000000000000 R12: ffffaffcc0d4f9f8
[ 4.212462] R13: ffffaffcc0d4f9f8 R14: 0000000000000000 R15: ffff97218bc8a000
[ 4.212464] FS: 0000000000000000(0000) GS:ffff973ee1ad9000(0000) knlGS:0000000000000000
[ 4.212465] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 4.212467] CR2: 00005640b0f29360 CR3: 0000000ccb224000 CR4: 0000000000f50ef0
[ 4.212469] PKRU: 55555554
[ 4.212470] Call Trace:
[ 4.212473] <TASK>
[ 4.212478] pci_bus_distribute_available_resources+0x590/0x6d0
[ 4.212483] pci_bridge_distribute_available_resources+0x62/0xb0
[ 4.212487] pci_assign_unassigned_bridge_resources+0x65/0x1b0
[ 4.212490] pciehp_configure_device+0x92/0x160
[ 4.212495] pciehp_handle_presence_or_link_change+0x1b5/0x350
[ 4.212498] pciehp_ist+0x147/0x1c0
[ 4.212502] irq_thread_fn+0x20/0x60
[ 4.212508] irq_thread+0x1cc/0x360
[ 4.212511] ? __pfx_irq_thread_fn+0x10/0x10
[ 4.212515] ? __pfx_irq_thread_dtor+0x10/0x10
[ 4.212518] ? __pfx_irq_thread+0x10/0x10
[ 4.212521] kthread+0xf9/0x240
[ 4.212525] ? __pfx_kthread+0x10/0x10
[ 4.212528] ret_from_fork+0x195/0x1d0
[ 4.212533] ? __pfx_kthread+0x10/0x10
[ 4.212536] ret_from_fork_asm+0x1a/0x30
[ 4.212540] </TASK>
[ 4.212541] ---[ end trace 0000000000000000 ]—
Perhaps there's something you forgot to modify while copying and
pasting, as shown below:
> On 29 Aug 2025, at 21:11, Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> wrote:
>
> pci_bus_distribute_available_resources() and
> pci_bridge_distribute_available_resources() retain bridge window resources
> and related data needed for distributing the available window in
> independent variables for io, memory, and prefetchable memory windows. The
> code is essentially the same for all of them and therefore repeated three
> times with different variable names.
>
> Refactor pci_bus_distribute_available_resources() to take an array. This
> is complicated slightly by the function taking advantage of passing the
> struct as value, which cannot be done for arrays in C. Therefore, copy the
> data into a local array in the stack in the first loop.
>
> Variable names are (hopefully) improved slightly as well.
>
> Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
> ---
> drivers/pci/setup-bus.c | 162 ++++++++++++++++++----------------------
> include/linux/pci.h | 3 +-
> 2 files changed, 74 insertions(+), 91 deletions(-)
>
> diff --git a/drivers/pci/setup-bus.c b/drivers/pci/setup-bus.c
> index 720159bca54d..3bc329b1b923 100644
> --- a/drivers/pci/setup-bus.c
> +++ b/drivers/pci/setup-bus.c
> @@ -2059,15 +2059,16 @@ static void remove_dev_resource(struct resource *avail, struct pci_dev *dev,
> avail->start = min(avail->start + tmp, avail->end + 1);
> }
>
> -static void remove_dev_resources(struct pci_dev *dev, struct resource *io,
> - struct resource *mmio,
> - struct resource *mmio_pref)
> +static void remove_dev_resources(struct pci_dev *dev,
> + struct resource available[PCI_P2P_BRIDGE_RESOURCE_NUM])
> {
> + struct resource *mmio_pref = &available[PCI_BUS_BRIDGE_PREF_MEM_WINDOW];
> struct resource *res;
>
> pci_dev_for_each_resource(dev, res) {
> if (resource_type(res) == IORESOURCE_IO) {
> - remove_dev_resource(io, dev, res);
> + remove_dev_resource(&available[PCI_BUS_BRIDGE_IO_WINDOW],
> + dev, res);
> } else if (resource_type(res) == IORESOURCE_MEM) {
>
> /*
> @@ -2081,10 +2082,13 @@ static void remove_dev_resources(struct pci_dev *dev, struct resource *io,
> */
> if ((res->flags & IORESOURCE_PREFETCH) &&
> ((res->flags & IORESOURCE_MEM_64) ==
> - (mmio_pref->flags & IORESOURCE_MEM_64)))
> - remove_dev_resource(mmio_pref, dev, res);
> - else
> - remove_dev_resource(mmio, dev, res);
> + (mmio_pref->flags & IORESOURCE_MEM_64))) {
> + remove_dev_resource(&available[PCI_BUS_BRIDGE_PREF_MEM_WINDOW],
> + dev, res);
> + } else {
> + remove_dev_resource(&available[PCI_BUS_BRIDGE_MEM_WINDOW],
> + dev, res);
> + }
> }
> }
> }
> @@ -2099,45 +2103,39 @@ static void remove_dev_resources(struct pci_dev *dev, struct resource *io,
> * shared with the bridges.
> */
> static void pci_bus_distribute_available_resources(struct pci_bus *bus,
> - struct list_head *add_list,
> - struct resource io,
> - struct resource mmio,
> - struct resource mmio_pref)
> + struct list_head *add_list,
> + struct resource available_in[PCI_P2P_BRIDGE_RESOURCE_NUM])
> {
> + struct resource available[PCI_P2P_BRIDGE_RESOURCE_NUM];
> unsigned int normal_bridges = 0, hotplug_bridges = 0;
> - struct resource *io_res, *mmio_res, *mmio_pref_res;
> struct pci_dev *dev, *bridge = bus->self;
> - resource_size_t io_per_b, mmio_per_b, mmio_pref_per_b, align;
> + resource_size_t per_bridge[PCI_P2P_BRIDGE_RESOURCE_NUM];
> + resource_size_t align;
> + int i;
>
> - io_res = &bridge->resource[PCI_BRIDGE_IO_WINDOW];
> - mmio_res = &bridge->resource[PCI_BRIDGE_MEM_WINDOW];
> - mmio_pref_res = &bridge->resource[PCI_BRIDGE_PREF_MEM_WINDOW];
> + for (i = 0; i < PCI_P2P_BRIDGE_RESOURCE_NUM; i++) {
> + struct resource *res = pci_bus_resource_n(bus, i);
Here should be: pci_resource_n(bridge, PCI_BRIDGE_RESOURCES + i);
>
> - /*
> - * The alignment of this bridge is yet to be considered, hence it must
> - * be done now before extending its bridge window.
> - */
> - align = pci_resource_alignment(bridge, io_res);
> - if (!io_res->parent && align)
> - io.start = min(ALIGN(io.start, align), io.end + 1);
> -
> - align = pci_resource_alignment(bridge, mmio_res);
> - if (!mmio_res->parent && align)
> - mmio.start = min(ALIGN(mmio.start, align), mmio.end + 1);
> + available[i] = available_in[i];
>
> - align = pci_resource_alignment(bridge, mmio_pref_res);
> - if (!mmio_pref_res->parent && align)
> - mmio_pref.start = min(ALIGN(mmio_pref.start, align),
> - mmio_pref.end + 1);
> + /*
> + * The alignment of this bridge is yet to be considered,
> + * hence it must be done now before extending its bridge
> + * window.
> + */
> + align = pci_resource_alignment(bridge, res);
> + if (!res->parent && align)
> + available[i].start = min(ALIGN(available[i].start, align),
> + available[i].end + 1);
>
> - /*
> - * Now that we have adjusted for alignment, update the bridge window
> - * resources to fill as much remaining resource space as possible.
> - */
> - adjust_bridge_window(bridge, io_res, add_list, resource_size(&io));
> - adjust_bridge_window(bridge, mmio_res, add_list, resource_size(&mmio));
> - adjust_bridge_window(bridge, mmio_pref_res, add_list,
> - resource_size(&mmio_pref));
> + /*
> + * Now that we have adjusted for alignment, update the
> + * bridge window resources to fill as much remaining
> + * resource space as possible.
> + */
> + adjust_bridge_window(bridge, res, add_list,
> + resource_size(&available[i]));
> + }
>
> /*
> * Calculate how many hotplug bridges and normal bridges there
> @@ -2161,7 +2159,7 @@ static void pci_bus_distribute_available_resources(struct pci_bus *bus,
> */
> list_for_each_entry(dev, &bus->devices, bus_list) {
> if (!dev->is_virtfn)
> - remove_dev_resources(dev, &io, &mmio, &mmio_pref);
> + remove_dev_resources(dev, available);
> }
>
> /*
> @@ -2173,16 +2171,9 @@ static void pci_bus_distribute_available_resources(struct pci_bus *bus,
> * split between non-hotplug bridges. This is to allow possible
> * hotplug bridges below them to get the extra space as well.
> */
> - if (hotplug_bridges) {
> - io_per_b = div64_ul(resource_size(&io), hotplug_bridges);
> - mmio_per_b = div64_ul(resource_size(&mmio), hotplug_bridges);
> - mmio_pref_per_b = div64_ul(resource_size(&mmio_pref),
> - hotplug_bridges);
> - } else {
> - io_per_b = div64_ul(resource_size(&io), normal_bridges);
> - mmio_per_b = div64_ul(resource_size(&mmio), normal_bridges);
> - mmio_pref_per_b = div64_ul(resource_size(&mmio_pref),
> - normal_bridges);
> + for (i = 0; i < PCI_P2P_BRIDGE_RESOURCE_NUM; i++) {
> + per_bridge[i] = div64_ul(resource_size(&available[i]),
> + hotplug_bridges ?: normal_bridges);
> }
>
> for_each_pci_bridge(dev, bus) {
> @@ -2195,49 +2186,41 @@ static void pci_bus_distribute_available_resources(struct pci_bus *bus,
> if (hotplug_bridges && !dev->is_hotplug_bridge)
> continue;
>
> - res = &dev->resource[PCI_BRIDGE_IO_WINDOW];
> + for (i = 0; i < PCI_P2P_BRIDGE_RESOURCE_NUM; i++) {
> + res = pci_bus_resource_n(bus, i);
Same here, should be: pci_resource_n(dev, PCI_BRIDGE_RESOURCES + i);
I have written a patch to resolve these issues:
https://lore.kernel.org/lkml/tencent_8C54420E1B0FF8D804C1B4651DF970716309@qq.com/
Thanks,
Yangyu Chen
>
> - /*
> - * Make sure the split resource space is properly aligned
> - * for bridge windows (align it down to avoid going above
> - * what is available).
> - */
> - align = pci_resource_alignment(dev, res);
> - resource_set_size(&io, ALIGN_DOWN_IF_NONZERO(io_per_b, align));
> -
> - /*
> - * The x_per_b holds the extra resource space that can be
> - * added for each bridge but there is the minimal already
> - * reserved as well so adjust x.start down accordingly to
> - * cover the whole space.
> - */
> - io.start -= resource_size(res);
> -
> - res = &dev->resource[PCI_BRIDGE_MEM_WINDOW];
> - align = pci_resource_alignment(dev, res);
> - resource_set_size(&mmio,
> - ALIGN_DOWN_IF_NONZERO(mmio_per_b,align));
> - mmio.start -= resource_size(res);
> + /*
> + * Make sure the split resource space is properly
> + * aligned for bridge windows (align it down to
> + * avoid going above what is available).
> + */
> + align = pci_resource_alignment(dev, res);
> + resource_set_size(&available[i],
> + ALIGN_DOWN_IF_NONZERO(per_bridge[i],
> + align));
>
> - res = &dev->resource[PCI_BRIDGE_PREF_MEM_WINDOW];
> - align = pci_resource_alignment(dev, res);
> - resource_set_size(&mmio_pref,
> - ALIGN_DOWN_IF_NONZERO(mmio_pref_per_b, align));
> - mmio_pref.start -= resource_size(res);
> + /*
> + * The per_bridge holds the extra resource space
> + * that can be added for each bridge but there is
> + * the minimal already reserved as well so adjust
> + * x.start down accordingly to cover the whole
> + * space.
> + */
> + available[i].start -= resource_size(res);
> + }
>
> - pci_bus_distribute_available_resources(b, add_list, io, mmio,
> - mmio_pref);
> + pci_bus_distribute_available_resources(b, add_list, available);
>
> - io.start += io.end + 1;
> - mmio.start += mmio.end + 1;
> - mmio_pref.start += mmio_pref.end + 1;
> + for (i = 0; i < PCI_P2P_BRIDGE_RESOURCE_NUM; i++)
> + available[i].start += available[i].end + 1;
> }
> }
>
> static void pci_bridge_distribute_available_resources(struct pci_dev *bridge,
> struct list_head *add_list)
> {
> - struct resource available_io, available_mmio, available_mmio_pref;
> + struct resource *res, available[PCI_P2P_BRIDGE_RESOURCE_NUM];
> + unsigned int i;
>
> if (!bridge->is_hotplug_bridge)
> return;
> @@ -2245,14 +2228,13 @@ static void pci_bridge_distribute_available_resources(struct pci_dev *bridge,
> pci_dbg(bridge, "distributing available resources\n");
>
> /* Take the initial extra resources from the hotplug port */
> - available_io = bridge->resource[PCI_BRIDGE_IO_WINDOW];
> - available_mmio = bridge->resource[PCI_BRIDGE_MEM_WINDOW];
> - available_mmio_pref = bridge->resource[PCI_BRIDGE_PREF_MEM_WINDOW];
> + for (i = 0; i < PCI_P2P_BRIDGE_RESOURCE_NUM; i++) {
> + res = pci_resource_n(bridge, PCI_BRIDGE_RESOURCES + i);
> + available[i] = *res;
> + }
>
> pci_bus_distribute_available_resources(bridge->subordinate,
> - add_list, available_io,
> - available_mmio,
> - available_mmio_pref);
> + add_list, available);
> }
>
> static bool pci_bridge_resources_not_assigned(struct pci_dev *dev)
> diff --git a/include/linux/pci.h b/include/linux/pci.h
> index 275df4058767..723e9cede69d 100644
> --- a/include/linux/pci.h
> +++ b/include/linux/pci.h
> @@ -119,7 +119,8 @@ enum {
> #define PCI_CB_BRIDGE_MEM_1_WINDOW (PCI_BRIDGE_RESOURCES + 3)
>
> /* Total number of bridge resources for P2P and CardBus */
> -#define PCI_BRIDGE_RESOURCE_NUM 4
> +#define PCI_P2P_BRIDGE_RESOURCE_NUM 3
> +#define PCI_BRIDGE_RESOURCE_NUM 4
>
> /* Resources assigned to buses behind the bridge */
> PCI_BRIDGE_RESOURCES,
> --
> 2.39.5
>
>
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