[PATCH v10 58/59] PCI: Don't set flags to 0 when assign resource fail

From: Yinghai Lu
Date: Wed Feb 24 2016 - 21:20:03 EST


We want to keep resource flags instead of clearing it after resource
allocation fails.

Make flags take IORESOURCE_UNSET | IORESOURCE_DISABLED instead.

Suggested-by: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>
Signed-off-by: Yinghai Lu <yinghai@xxxxxxxxxx>
---
drivers/pci/bus.c | 2 +-
drivers/pci/setup-bus.c | 45 +++++++++++++++++++++++----------------------
drivers/pci/setup-res.c | 3 ++-
3 files changed, 26 insertions(+), 24 deletions(-)

diff --git a/drivers/pci/bus.c b/drivers/pci/bus.c
index 7f7bf04..e71c60d 100644
--- a/drivers/pci/bus.c
+++ b/drivers/pci/bus.c
@@ -142,7 +142,7 @@ static int pci_bus_alloc_from_region(struct pci_bus *bus, struct resource *res,
pci_bus_for_each_resource(bus, r, i) {
resource_size_t min_used = min;

- if (!r)
+ if (!r || resource_disabled(r))
continue;

/* type_mask must match */
diff --git a/drivers/pci/setup-bus.c b/drivers/pci/setup-bus.c
index dd764c4..e1d7b79 100644
--- a/drivers/pci/setup-bus.c
+++ b/drivers/pci/setup-bus.c
@@ -264,13 +264,6 @@ static void __dev_assign_resources_prepare(struct pci_dev *dev,
pdev_assign_resources_prepare(dev, realloc_head, head);
}

-static inline void reset_resource(struct resource *res)
-{
- res->start = 0;
- res->end = 0;
- res->flags = 0;
-}
-
static void sort_resources(struct list_head *head)
{
struct pci_dev_resource *res1, *tmp_res, *res2;
@@ -337,7 +330,7 @@ static void reassign_resources_sorted(struct list_head *realloc_head,
res->start = align;
res->end = res->start + add_size - 1;
if (pci_assign_resource(add_res->dev, idx))
- reset_resource(res);
+ res->flags |= IORESOURCE_DISABLED;
} else {
/* could just assigned with alt, add difference ? */
resource_size_t size;
@@ -391,7 +384,7 @@ static void assign_requested_resources_sorted(struct list_head *head,
pci_assign_resource(dev_res->dev, idx)) {
if (fail_head)
add_to_list(fail_head, dev_res->dev, res);
- reset_resource(res);
+ res->flags |= IORESOURCE_DISABLED;
}
}
}
@@ -677,7 +670,7 @@ static void __assign_resources_alt_sorted(struct list_head *head,

if (!res_to_dev_res(local_fail_head, res))
add_to_list(local_fail_head, fail_res->dev, res);
- reset_resource(res);
+ res->flags |= IORESOURCE_UNSET | IORESOURCE_DISABLED;
}
free_list(&local_alt_fail_head);
}
@@ -843,7 +836,7 @@ static void pci_setup_bridge_io(struct pci_dev *bridge)
/* Set up the top and bottom of the PCI I/O segment for this bus. */
res = &bridge->resource[PCI_BRIDGE_RESOURCES + 0];
pcibios_resource_to_bus(bridge->bus, &region, res);
- if (res->flags & IORESOURCE_IO) {
+ if ((res->flags & IORESOURCE_IO) && !(res->flags & IORESOURCE_UNSET)) {
pci_read_config_word(bridge, PCI_IO_BASE, &l);
io_base_lo = (region.start >> 8) & io_mask;
io_limit_lo = (region.end >> 8) & io_mask;
@@ -873,7 +866,8 @@ static void pci_setup_bridge_mmio(struct pci_dev *bridge)
/* Set up the top and bottom of the PCI Memory segment for this bus. */
res = &bridge->resource[PCI_BRIDGE_RESOURCES + 1];
pcibios_resource_to_bus(bridge->bus, &region, res);
- if (res->flags & IORESOURCE_MEM) {
+ if ((res->flags & IORESOURCE_MEM) &&
+ !(res->flags & IORESOURCE_UNSET)) {
l = (region.start >> 16) & 0xfff0;
l |= region.end & 0xfff00000;
dev_info(&bridge->dev, " bridge window %pR\n", res);
@@ -898,7 +892,8 @@ static void pci_setup_bridge_mmio_pref(struct pci_dev *bridge)
bu = lu = 0;
res = &bridge->resource[PCI_BRIDGE_RESOURCES + 2];
pcibios_resource_to_bus(bridge->bus, &region, res);
- if (res->flags & IORESOURCE_PREFETCH) {
+ if ((res->flags & IORESOURCE_PREFETCH) &&
+ !(res->flags & IORESOURCE_UNSET)) {
l = (region.start >> 16) & 0xfff0;
l |= region.end & 0xfff00000;
if (res->flags & IORESOURCE_MEM_64) {
@@ -1028,6 +1023,7 @@ static void pci_bridge_check_ranges(struct pci_bus *bus)

b_res = &bridge->resource[PCI_BRIDGE_RESOURCES];
b_res[1].flags |= IORESOURCE_MEM;
+ b_res[1].flags &= ~IORESOURCE_DISABLED;

pci_read_config_word(bridge, PCI_IO_BASE, &io);
if (!io) {
@@ -1035,8 +1031,10 @@ static void pci_bridge_check_ranges(struct pci_bus *bus)
pci_read_config_word(bridge, PCI_IO_BASE, &io);
pci_write_config_word(bridge, PCI_IO_BASE, 0x0);
}
- if (io)
+ if (io) {
b_res[0].flags |= IORESOURCE_IO;
+ b_res[0].flags &= ~IORESOURCE_DISABLED;
+ }

/* DECchip 21050 pass 2 errata: the bridge may miss an address
disconnect boundary by one PCI data phase.
@@ -1053,6 +1051,7 @@ static void pci_bridge_check_ranges(struct pci_bus *bus)
}
if (pmem) {
b_res[2].flags |= IORESOURCE_MEM | IORESOURCE_PREFETCH;
+ b_res[2].flags &= ~IORESOURCE_DISABLED;
if ((pmem & PCI_PREF_RANGE_TYPE_MASK) ==
PCI_PREF_RANGE_TYPE_64) {
b_res[2].flags |= IORESOURCE_MEM_64;
@@ -1198,8 +1197,10 @@ static void pbus_size_io(struct pci_bus *bus, resource_size_t min_size,
struct resource *r = &dev->resource[i];
unsigned long r_size, r_add_size;

- if (r->parent || !(r->flags & IORESOURCE_IO))
+ if (r->parent || !(r->flags & IORESOURCE_IO) ||
+ resource_disabled(r))
continue;
+
r_size = resource_size(r);

if (r_size < 0x400)
@@ -1240,7 +1241,7 @@ static void pbus_size_io(struct pci_bus *bus, resource_size_t min_size,
if (b_res->start || b_res->end)
dev_info(&bus->self->dev, "disabling bridge window %pR to %pR (unused)\n",
b_res, &bus->busn_res);
- b_res->flags = 0;
+ b_res->flags |= IORESOURCE_UNSET | IORESOURCE_DISABLED;
return;
}

@@ -1533,7 +1534,8 @@ static int pbus_size_mem(struct pci_bus *bus, unsigned long mask,
if (r->parent || (flags & IORESOURCE_PCI_FIXED) ||
((flags & mask) != type &&
(flags & mask) != type2 &&
- (flags & mask) != type3))
+ (flags & mask) != type3) ||
+ resource_disabled(r))
continue;

r_size = resource_size(r);
@@ -1554,7 +1556,8 @@ static int pbus_size_mem(struct pci_bus *bus, unsigned long mask,
if (align > (1ULL<<37)) { /*128 Gb*/
dev_warn(&dev->dev, "disabling BAR %d: %pR (bad alignment %#llx)\n",
i, r, (unsigned long long) align);
- r->flags = 0;
+ r->flags |= IORESOURCE_UNSET |
+ IORESOURCE_DISABLED;
continue;
}

@@ -1651,7 +1654,7 @@ static int pbus_size_mem(struct pci_bus *bus, unsigned long mask,
if (b_res->start || b_res->end)
dev_info(&bus->self->dev, "disabling bridge window %pR to %pR (unused)\n",
b_res, &bus->busn_res);
- b_res->flags = 0;
+ b_res->flags |= IORESOURCE_UNSET | IORESOURCE_DISABLED;
return 0;
}

@@ -2111,7 +2114,7 @@ static void pci_bridge_release_resources(struct pci_bus *bus,
/* keep the old size */
r->end = resource_size(r) - 1;
r->start = 0;
- r->flags = 0;
+ r->flags |= IORESOURCE_UNSET | IORESOURCE_DISABLED;

/* avoiding touch the one without PREF */
if (type & IORESOURCE_PREFETCH)
@@ -2380,7 +2383,6 @@ again:

restore_resource(fail_res, res);
if (fail_res->dev->subordinate) {
- res->flags = 0;
/* last or third times and later */
if (tried_times + 1 == pci_try_num ||
tried_times + 1 > 2)
@@ -2464,7 +2466,6 @@ again:

restore_resource(fail_res, res);
if (fail_res->dev->subordinate) {
- res->flags = 0;
/* last time */
reset_bridge_resource_size(fail_res->dev, res);
}
diff --git a/drivers/pci/setup-res.c b/drivers/pci/setup-res.c
index b196fcd..2a07e39 100644
--- a/drivers/pci/setup-res.c
+++ b/drivers/pci/setup-res.c
@@ -371,7 +371,8 @@ int pci_enable_resources(struct pci_dev *dev, int mask)

r = &dev->resource[i];

- if (!(r->flags & (IORESOURCE_IO | IORESOURCE_MEM)))
+ if (!(r->flags & (IORESOURCE_IO | IORESOURCE_MEM)) ||
+ resource_disabled(r))
continue;
if ((i == PCI_ROM_RESOURCE) &&
(!(r->flags & IORESOURCE_ROM_ENABLE)))
--
1.8.4.5